National Library of Energy BETA

Sample records for oxygen species ros

  1. Controllable generation of reactive oxygen species by femtosecond-laser irradiation

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    Yan, Wei; He, Hao Wang, Yintao; Wang, Yisen; Hu, Minglie; Wang, Chingyue

    2014-02-24

    Femtosecond lasers have been advancing Biophotonics research in the past two decades with multiphoton microscopy, microsurgery, and photodynamic therapy. Nevertheless, laser irradiation is identified to bring photodamage to cells via reactive oxygen species (ROS) generation with unclear mechanism. Meanwhile, currently in biological researches, there is no effective method to provide controllable ROS production precisely, which originally is leaked from mitochondria during respiration and plays a key role in a lot of important cellular processes and cellular signaling pathways. In this study, we show the process of how the tightly focused femtosecond-laser induces ROS generation solely in mitochondria at the very beginning and then release to cytosol if the stimulus is intense enough. At certain weak power levels, the laser pulses induce merely moderate Ca{sup 2+} release but this is necessary for the laser to generate ROS in mitochondria. Cellular original ROS are also involved with a small contribution. When the power is above a threshold, ROS are then released to cytosol, indicating photodamage overwhelming cellular repair ability. The mechanisms in those two cases are quite different. Those results clarify parts of the mechanism in laser-induced ROS generation. Hence, it is possible to further this optical scheme to provide controllable ROS generation for ROS-related biological researches including mitochondrial diseases and aging.

  2. Role of reactive oxygen species in arsenic-induced transformation of human lung bronchial epithelial (BEAS-2B) cells

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    Zhang, Zhuo; Pratheeshkumar, Poyil; Budhraja, Amit; Son, Young-Ok; Kim, Donghern; Shi, Xianglin

    2015-01-09

    Highlights: • Short term exposure of cells to arsenic causes ROS generation. • Chronical exposure of cells to arsenic causes malignant cell transformation. • Inhibition of ROS generation reduces cell transformation by arsenic. • Arsenic-transformed cells exhibit reduced capacity of generating ROS. • Arsenic-transformed cells exhibit increased levels of antioxidants. - Abstract: Arsenic is an environmental carcinogen, its mechanisms of carcinogenesis remain to be investigated. Reactive oxygen species (ROS) are considered to be important. A previous study (Carpenter et al., 2011) has measured ROS level in human lung bronchial epithelial (BEAS-2B) cells and arsenic-transformed BEAS-2B cells and found that ROS levels were higher in transformed cells than that in parent normal cells. Based on these observations, the authors concluded that cell transformation induced by arsenic is mediated by increased cellular levels of ROS. This conclusion is problematic because this study only measured the basal ROS levels in transformed and parent cells and did not investigate the role of ROS in the process of arsenic-induced cell transformation. The levels of ROS in arsenic-transformed cells represent the result and not the cause of cell transformation. Thus question concerning whether ROS are important in arsenic-induced cell transformation remains to be answered. In the present study, we used expressions of catalase (antioxidant against H{sub 2}O{sub 2}) and superoxide dismutase 2 (SOD2, antioxidant against O{sub 2}{sup ·−}) to decrease ROS level and investigated their role in the process of arsenic-induced cell transformation. Our results show that inhibition of ROS by antioxidant enzymes decreased arsenic-induced cell transformation, demonstrating that ROS are important in this process. We have also shown that in arsenic-transformed cells, ROS generation was lower and levels of antioxidants are higher than those in parent cells, in a disagreement with the previous

  3. Arsenite induces cell transformation by reactive oxygen species, AKT, ERK1/2, and p70S6K1

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    Carpenter, Richard L.; Jiang, Yue; Jing, Yi; He, Jun; Rojanasakul, Yon; Liu, Ling-Zhi; Jiang, Bing-Hua

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer Chronic exposure to arsenite induces cell proliferation and transformation. Black-Right-Pointing-Pointer Arsenite-induced transformation increases ROS production and downstream signalings. Black-Right-Pointing-Pointer Inhibition of ROS levels via catalase reduces arsenite-induced cell transformation. Black-Right-Pointing-Pointer Interruption of AKT, ERK, or p70S6K1 inhibits arsenite-induced cell transformation. -- Abstract: Arsenic is naturally occurring element that exists in both organic and inorganic formulations. The inorganic form arsenite has a positive association with development of multiple cancer types. There are significant populations throughout the world with high exposure to arsenite via drinking water. Thus, human exposure to arsenic has become a significant public health problem. Recent evidence suggests that reactive oxygen species (ROS) mediate multiple changes to cell behavior after acute arsenic exposure, including activation of proliferative signaling and angiogenesis. However, the role of ROS in mediating cell transformation by chronic arsenic exposure is unknown. We found that cells chronically exposed to sodium arsenite increased proliferation and gained anchorage-independent growth. This cell transformation phenotype required constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. We also observed these cells constitutively produce ROS, which was required for the constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. Suppression of ROS levels by forced expression of catalase also reduced cell proliferation and anchorage-independent growth. These results indicate cell transformation induced by chronic arsenic exposure is mediated by increased cellular levels of ROS, which mediates activation of AKT, ERK1/2, and p70S6K1.

  4. IGF-I enhances cellular senescence via the reactive oxygen species-p53 pathway

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    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro; Takahashi, Yutaka

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Cellular senescence plays an important role in tumorigenesis and aging process. Black-Right-Pointing-Pointer We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. Black-Right-Pointing-Pointer IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. Black-Right-Pointing-Pointer These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated {beta}-galactosidase (SA-{beta}-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, {gamma}H2AX, the increased levels of p53 and p21 proteins, and activated SA-{beta}-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-{beta}-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  5. Direct Observation of the Oxygenated Species during Oxygen Reduction on a

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    Platinum Fuel Cell Cathode | Stanford Synchrotron Radiation Lightsource Direct Observation of the Oxygenated Species during Oxygen Reduction on a Platinum Fuel Cell Cathode Friday, December 20, 2013 Fuel Cell Figure 1 Figure 1. In situ x-ray spectroscopy identification and DFT simulations of oxygenated intermediates on a platinum fuel-cell cathode. The study shows that two types of hydroxyl intermediates (non-hydrated OH and hydrated OH) with distinct activities coexist on a fuel-cell

  6. Properties of reactive oxygen species by quantum Monte Carlo

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    Zen, Andrea; Trout, Bernhardt L.; Guidoni, Leonardo

    2014-07-07

    The electronic properties of the oxygen molecule, in its singlet and triplet states, and of many small oxygen-containing radicals and anions have important roles in different fields of chemistry, biology, and atmospheric science. Nevertheless, the electronic structure of such species is a challenge for ab initio computational approaches because of the difficulties to correctly describe the statical and dynamical correlation effects in presence of one or more unpaired electrons. Only the highest-level quantum chemical approaches can yield reliable characterizations of their molecular properties, such as binding energies, equilibrium structures, molecular vibrations, charge distribution, and polarizabilities. In this work we use the variational Monte Carlo (VMC) and the lattice regularized Monte Carlo (LRDMC) methods to investigate the equilibrium geometries and molecular properties of oxygen and oxygen reactive species. Quantum Monte Carlo methods are used in combination with the Jastrow Antisymmetrized Geminal Power (JAGP) wave function ansatz, which has been recently shown to effectively describe the statical and dynamical correlation of different molecular systems. In particular, we have studied the oxygen molecule, the superoxide anion, the nitric oxide radical and anion, the hydroxyl and hydroperoxyl radicals and their corresponding anions, and the hydrotrioxyl radical. Overall, the methodology was able to correctly describe the geometrical and electronic properties of these systems, through compact but fully-optimised basis sets and with a computational cost which scales as N{sup 3} ? N{sup 4}, where N is the number of electrons. This work is therefore opening the way to the accurate study of the energetics and of the reactivity of large and complex oxygen species by first principles.

  7. Study of the photochemically generated of oxygen species by fullerene photosensitized CoS{sub 2} nanocompounds

    SciTech Connect (OSTI)

    Meng, Ze-Da; Zhu, Lei; Ullah, Kefayat; Ye, Shu; Sun, Qian; Jang, Won Kweon; Oh, Won-Chun

    2014-01-01

    Graphical abstract: - Highlights: Reactive oxygen species was detected through oxidation reaction from DPCI to DPCO. Generated reactive oxygen species and hydroxyl radicals can be analysis by DPCI degradation. C{sub 60} has good effect during the photo-degradation processes. Photocatalytic activity attributed to photo-absorption effect by C{sub 60} and cooperative effect of CoS{sub 2}. - Abstract: Reactive oxygen species (ROS) can be produced by interactions between sunlight and light-absorbing substance in natural water environment and can completely destroy various organic pollutants in wastewaters. In this study, CoS{sub 2} and CoS{sub 2}fullerene were irradiated by visible light respectively. The generation of reactive oxygen species were detected through the oxidation reaction from 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). In comparison with the separate effects of CoS{sub 2} and fullerene nanoparticles, the photochemically effect of the fullerene photosensitized CoS{sub 2} composites is increased significantly due to the synergetic effect between the fullerene and the CoS{sub 2} nanoparticles.

  8. In utero and in vitro effects of benzene and its metabolites on erythroid differentiation and the role of reactive oxygen species

    SciTech Connect (OSTI)

    Badham, Helen J.; Winn, Louise M.

    2010-05-01

    Benzene is a ubiquitous occupational and environmental toxicant. Exposures to benzene both prenatally and during adulthood are associated with the development of disorders such as aplastic anemia and leukemia. Mechanisms of benzene toxicity are unknown; however, generation of reactive oxygen species (ROS) by benzene metabolites may play a role. Little is known regarding the effects of benzene metabolites on erythropoiesis. Therefore, to determine the effects of in utero exposure to benzene on the growth and differentiation of fetal erythroid progenitor cells (CFU-E), pregnant CD-1 mice were exposed to benzene and CFU-E numbers were assessed in fetal liver (hematopoietic) tissue. In addition, to determine the effect of benzene metabolite-induced ROS generation on erythropoiesis, HD3 chicken erythroblast cells were exposed to benzene, phenol, or hydroquinone followed by stimulation of erythrocyte differentiation. Our results show that in utero exposure to benzene caused significant alterations in female offspring CFU-E numbers. In addition, exposure to hydroquinone, but not benzene or phenol, significantly reduced the percentage of differentiated HD3 cells, which was associated with an increase in ROS. Pretreatment of HD3 cells with polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) prevented hydroquinone-induced inhibition of erythropoiesis, supporting the hypothesis that ROS generation is involved in the development of benzene erythrotoxicity. In conclusion, this study provided evidence that ROS generated as a result of benzene metabolism may significantly alter erythroid differentiation, potentially leading to the development of Blood Disorders.

  9. Involvement of reactive oxygen species in brominated diphenyl ether-47-induced inflammatory cytokine release from human extravillous trophoblasts in vitro

    SciTech Connect (OSTI)

    Park, Hae-Ryung Kamau, Patricia W.; Loch-Caruso, Rita

    2014-01-15

    Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant compounds. Brominated diphenyl ether (BDE)-47 is one of the most prevalent PBDE congeners found in human breast milk, serum and placenta. Despite the presence of PBDEs in human placenta, effects of PBDEs on placental cell function are poorly understood. The present study investigated BDE-47-induced reactive oxygen species (ROS) formation and its role in BDE-47-stimulated proinflammatory cytokine release in a first trimester human extravillous trophoblast cell line, HTR-8/SVneo. Exposure of HTR-8/SVneo cells for 4 h to 20 ?M BDE-47 increased ROS generation 1.7 fold as measured by the dichlorofluorescein (DCF) assay. Likewise, superoxide anion production increased approximately 5 fold at 10 and 15 ?M and 9 fold at 20 ?M BDE-47 with a 1-h exposure, as measured by cytochrome c reduction. BDE-47 (10, 15 and 20 ?M) decreased the mitochondrial membrane potential by 4764.5% at 4, 8 and 24 h as assessed with the fluorescent probe Rh123. Treatment with 15 and 20 ?M BDE-47 stimulated cellular release and mRNA expression of IL-6 and IL-8 after 12 and 24-h exposures: the greatest increases were a 35-fold increased mRNA expression at 12 h and a 12-fold increased protein concentration at 24 h for IL-6. Antioxidant treatments (deferoxamine mesylate, ()?-tocopherol, or tempol) suppressed BDE-47-stimulated IL-6 release by 54.1%, 56.3% and 37.7%, respectively, implicating a role for ROS in the regulation of inflammatory pathways in HTR-8/SVneo cells. Solvent (DMSO) controls exhibited statistically significantly decreased responses compared with non-treated controls for IL-6 release and IL-8 mRNA expression, but these responses were not consistent across experiments and times. Nonetheless, it is possible that DMSO (used to dissolve BDE-47) may have attenuated the stimulatory actions of BDE-47 on cytokine responses. Because abnormal activation of proinflammatory responses can disrupt trophoblast functions

  10. The induction of reactive oxygen species and loss of mitochondrial Omi/HtrA2 is associated with S-nitrosoglutathione-induced apoptosis in human endothelial cells

    SciTech Connect (OSTI)

    Liu Qibing; Liu Lulu; Lu Yingmei; Tao Rongrong; Huang Jiyun; Shioda, Norifumi; Moriguchi, Shigeki; Fukunaga, Kohji; Han Feng; Lou Yijia

    2010-05-01

    The pathophysiological relevance of S-nitrosoglutathione (GSNO)-induced endothelial cell injury remains unclear. The main objective of this study was to elucidate the molecular mechanisms of GSNO-induced oxidative stress in endothelial cells. Morphological evaluation through DAPI staining and propidium iodide (PI) flow cytometry was used to detect apoptosis. In cultured EA.hy926 endothelial cells, exposure to GSNO led to a time- and dose-dependent apoptotic cascade. When intracellular reactive oxygen species (ROS) production was measured in GSNO-treated cells with the fluorescent probes 5-(and-6)-carboxy-2',7'-dichlorofluorescein diacetate, we observed elevated ROS levels and a concomitant loss in mitochondrial membrane potential, indicating that GSNO-induced death signaling is mediated through a ROS-mitochondrial pathway. Importantly, we found that peroxynitrite formation and Omi/HtrA2 release from mitochondria were involved in this phenomenon, whereas changes of death-receptor dependent signaling were not detected in the same context. The inhibition of NADPH oxidase activation and Omi/HtrA2 by a pharmacological approach provided significant protection against caspase-3 activation and GSNO-induced cell death, confirming that GSNO triggers the death cascade in endothelial cells in a mitochondria-dependent manner. Taken together, our results indicate that ROS overproduction and loss of mitochondrial Omi/HtrA2 play a pivotal role in reactive nitrogen species-induced cell death, and the modulation of these pathways can be of significant therapeutic benefit.

  11. Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

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    Smietana, Michael J.; Arruda, Ellen M.; Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109; Program in Macromolecular Science and Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 ; Faulkner, John A.; Brooks, Susan V.; Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 ; Larkin, Lisa M.

    2010-12-03

    Research highlights: {yields} Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. {yields} Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. {yields} Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1{sup -/-} mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1{sup -/-} mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm{sup 2}) and strength (MPa) is diminished in Sod1{sup -/-} compared to WT mice. Femurs were obtained from male and female WT and Sod1{sup -/-} mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1{sup -/-} mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1{sup -/-} mice compared to WT as well as between genders. These

  12. CR108, a novel vitamin K3 derivative induces apoptosis and breast tumor inhibition by reactive oxygen species and mitochondrial dysfunction

    SciTech Connect (OSTI)

    Yang, Chun-Ru; Liao, Wei-Siang; Wu, Ya-Hui; Murugan, Kaliyappan; Chen, Chinpiao; Chao, Jui-I

    2013-12-15

    Vitamin K3 derivatives have been shown to exert anticancer activities. Here we show a novel vitamin K3 derivative (S)-2-(2-hydroxy-3-methylbutylthio)naphthalene-1,4-dione, which is named as CR108 that induces apoptosis and tumor inhibition through reactive oxygen species (ROS) and mitochondrial dysfunction in human breast cancer. CR108 is more effective on the breast cancer cell death than other vitamin K3 derivatives. Moreover, CR108 induced apoptosis in both the non-HER-2-overexpressed MCF-7 and HER-2-overexpressed BT-474 breast cancer cells. CR108 caused the loss of mitochondrial membrane potential, cytochrome c released from mitochondria to cytosol, and cleaved PARP proteins for apoptosis induction. CR108 markedly increased ROS levels in breast cancer cells. N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the CR108-induced ROS levels, mitochondrial dysfunction and apoptosis. Interestingly, CR108 increased the phosphorylation of p38 MAP kinase but conversely inhibited the survivin protein expression. NAC treatment prevented the activation of p38 MAP kinase and rescued the survivin protein levels. SB202190, a specific p38 MAP kinase inhibitor, recovered the survivin protein levels and attenuated the cytotoxicity of CR108-treated cells. Furthermore, CR108 inhibited the xenografted human breast tumor growth in nude mice. Together, we demonstrate that CR108 is a novel vitamin K3 derivative that induces apoptosis and tumor inhibition by ROS production and mitochondrial dysfunction and associates with the phosphorylation of p38 MAP kinase and the inhibition of survivin in the human breast cancer. - Highlights: CR108 is more effective on the cell death than other vitamin K3 derivatives. CR108 induces apoptosis and tumor inhibition by ROS and mitochondrial dysfunction. CR108 induces apoptosis by p38 kinase activation and survivin inhibition. CR108 is a potent vitamin K3 analog that can develop for breast cancer therapy.

  13. Effects of UVA irradiation, aryl azides, and reactive oxygen species on the orthogonal inactivation of the human immunodeficiency virus (HIV-1)

    SciTech Connect (OSTI)

    Belanger, Julie M.; Raviv, Yossef; Viard, Mathias; Cruz, M. Jason de la; Nagashima, Kunio; Blumenthal, Robert

    2011-08-15

    Previously we reported that hydrophobic aryl azides partition into hydrophobic regions of the viral membrane of enveloped viruses and inactivate the virus upon UVA irradiation for 2 min. Prolonged irradiation (15 min) resulted in viral protein aggregation as visualized via Western blot analysis, due to reactive oxygen species (ROS) formation, with preservation of the surface antigenic epitopes. Herein, we demonstrate that these aggregates show detergent resistance and that this property may be useful towards the creation of a novel orthogonal virus inactivation strategy for use in preparing experimental vaccines. When ROS-modified HIV virus preparations were treated with 1% Triton X-100, there was an increase in the percent of viral proteins (gp41, p24) in the viral pellet after ultracentrifugation through sucrose. Transmission electron microscopy (TEM) of these detergent-resistant pellets shows some recognizable virus fragments, and immunoprecipitation studies of the gp41 aggregates suggest the aggregation is covalent in nature, involving short-range interactions.

  14. Hydroxylated polychlorinated biphenyls increase reactive oxygen species formation and induce cell death in cultured cerebellar granule cells

    SciTech Connect (OSTI)

    Dreiem, Anne Rykken, Sidsel; Lehmler, Hans-Joachim; Robertson, Larry W.; Fonnum, Frode

    2009-10-15

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants that bioaccumulate in the body, however, they can be metabolized to more water-soluble products. Although they are more readily excreted than the parent compounds, some of the metabolites are still hydrophobic and may be more available to target tissues, such as the brain. They can also cross the placenta and reach a developing foetus. Much less is known about the toxicity of PCB metabolites than about the parent compounds. In the present study, we have investigated the effects of eight hydroxylated (OH) PCB congeners (2'-OH PCB 3, 4-OH PCB 14, 4-OH PCB 34, 4'-OH PCB 35, 4-OH PCB 36, 4'-OH PCB 36, 4-OH PCB 39, and 4'-OH PCB 68) on reactive oxygen species (ROS) formation and cell viability in rat cerebellar granule cells. We found that, similar to their parent compounds, OH-PCBs are potent ROS inducers with potency 4-OH PCB 14 < 4-OH PCB 36 < 4-OH PCB 34 < 4'-OH PCB 36 < 4'-OH PCB 68 < 4-OH PCB 39 < 4'-OH PCB 35. 4-OH PCB 36 was the most potent cell death inducer, and caused apoptotic or necrotic morphology depending on concentration. Inhibition of ERK1/2 kinase with U0126 reduced both cell death and ROS formation, suggesting that ERK1/2 activation is involved in OH-PCB toxicity. The results indicate that the hydroxylation of PCBs may not constitute a detoxification reaction. Since OH-PCBs like their parent compounds are retained in the body and may be more widely distributed to sensitive tissues, it is important that not only the levels of the parent compounds but also the levels of their metabolites are taken into account during risk assessment of PCBs and related compounds.

  15. Phototoxicity of nano titanium dioxides in HaCaT keratinocytesGeneration of reactive oxygen species and cell damage

    SciTech Connect (OSTI)

    Yin, Jun-Jie; Liu, Jun; Ehrenshaft, Marilyn; Roberts, Joan E.; Fu, Peter P.; Mason, Ronald P.; Zhao, Baozhong

    2012-08-15

    Nano-sized titanium dioxide (TiO{sub 2}) is among the top five widely used nanomaterials for various applications. In this study, we determine the phototoxicity of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) with different molecular sizes and crystal forms (anatase and rutile) in human skin keratinocytes under UVA irradiation. Our results show that all nano-TiO{sub 2} particles caused phototoxicity, as determined by the MTS assay and by cell membrane damage measured by the lactate dehydrogenase (LDH) assay, both of which were UVA dose- and nano-TiO{sub 2} dose-dependent. The smaller the particle size of the nano-TiO{sub 2} the higher the cell damage. The rutile form of nano-TiO{sub 2} showed less phototoxicity than anatase nano-TiO{sub 2}. The level of photocytotoxicity and cell membrane damage is mainly dependent on the level of reactive oxygen species (ROS) production. Using polyunsaturated lipids in plasma membranes and human serum albumin as model targets, and employing electron spin resonance (ESR) oximetry and immuno-spin trapping as unique probing methods, we demonstrated that UVA irradiation of nano-TiO{sub 2} can induce significant cell damage, mediated by lipid and protein peroxidation. These overall results suggest that nano-TiO{sub 2} is phototoxic to human skin keratinocytes, and that this phototoxicity is mediated by ROS generated during UVA irradiation. Highlights: ? We evaluate the phototoxicity of nano-TiO{sub 2} with different sizes and crystal forms. ? The smaller the particle size of the nano-TiO{sub 2} the higher the cell damage. ? The rutile form of nano-TiO{sub 2} showed less phototoxicity than anatase nano-TiO{sub 2}. ? ESR oximetry and immuno-spin trapping techniques confirm UVA-induced cell damage. ? Phototoxicity is mediated by ROS generated during UVA irradiation of nano-TiO{sub 2}.

  16. A mutation in the mitochondrial protein UQCRB promotes angiogenesis through the generation of mitochondrial reactive oxygen species

    SciTech Connect (OSTI)

    Chang, Junghwa; Jung, Hye Jin; Jeong, Seung Hun; Kim, Hyoung Kyu; Han, Jin; Kwon, Ho Jeong

    2014-12-12

    Highlights: • We constructed mitochondrial protein UQCRB mutant stable cell lines on the basis of a human case report. • These mutant cell lines exhibit pro-angiogenic activity with enhanced VEGF expression. • Proliferation of mutant cell lines was regulated by UQCRB inhibitors. • UQCRB may have a functional role in angiogenesis. - Abstract: Ubiquinol-cytochrome c reductase binding protein (UQCRB) is one of the subunits of mitochondrial complex III and is a target protein of the natural anti-angiogenic small molecule terpestacin. Previously, the biological role of UQCRB was thought to be limited to the maintenance of complex III. However, the identification and validation of UQCRB as a target protein of terpestacin enabled the role of UQCRB in oxygen sensing and angiogenesis to be elucidated. To explore the biological role of this protein further, UQCRB mutant stable cell lines were generated on the basis of a human case report. We demonstrated that these cell lines exhibited glycolytic and pro-angiogenic activities via mitochondrial reactive oxygen species (mROS)-mediated HIF1 signal transduction. Furthermore, a morphological abnormality in mitochondria was detected in UQCRB mutant stable cell lines. In addition, the proliferative effect of the UQCRB mutants was significantly regulated by the UQCRB inhibitors terpestacin and A1938. Collectively, these results provide a molecular basis for UQCRB-related biological processes and reveal potential key roles of UQCRB in angiogenesis and mitochondria-mediated metabolic disorders.

  17. SNP in TXNRD2 Associated With Radiation-Induced Fibrosis: A Study of Genetic Variation in Reactive Oxygen Species Metabolism and Signaling

    SciTech Connect (OSTI)

    Edvardsen, Hege; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Landmark-Hyvik, Hege; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Reinertsen, Kristin V.; Zhao, Xi; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Grenaker-Alns, Grethe Irene; Nebdal, Daniel; Syvnen, Ann-Christine; Rdningen, Olaug; Alsner, Jan; Overgaard, Jens; Borresen-Dale, Anne-Lise; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Foss, Sophie D.; National Resource Centre for Late Effects after Cancer Treatment, OUS Radiumhospitalet, Oslo ; Kristensen, Vessela N.; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo; Department of Clinical Molecular Biology , Division of Medicine, Ahus University Hospital

    2013-07-15

    Purpose: The aim of the study was to identify noninvasive markers of treatment-induced side effects. Reactive oxygen species (ROS) are generated after irradiation, and genetic variation in genes related to ROS metabolism might influence the level of radiation-induced adverse effects (AEs). Methods and Materials: 92 breast cancer (BC) survivors previously treated with hypofractionated radiation therapy were assessed for the AEs subcutaneous atrophy and fibrosis, costal fractures, lung fibrosis, pleural thickening, and telangiectasias (median follow-up time 17.1 years). Single-nucleotide polymorphisms (SNPs) in 203 genes were analyzed for association to AE grade. SNPs associated with subcutaneous fibrosis were validated in an independent BC survivor material (n=283). The influence of the studied genetic variation on messenger ribonucleic acid (mRNA) expression level of 18 genes previously associated with fibrosis was assessed in fibroblast cell lines from BC patients. Results: Subcutaneous fibrosis and atrophy had the highest correlation (r=0.76) of all assessed AEs. The nonsynonymous SNP rs1139793 in TXNRD2 was associated with grade of subcutaneous fibrosis, the reference T-allele being more prevalent in the group experiencing severe levels of fibrosis. This was confirmed in another sample cohort of 283 BC survivors, and rs1139793 was found significantly associated with mRNA expression level of TXNRD2 in blood. Genetic variation in 24 ROS-related genes, including EGFR, CENPE, APEX1, and GSTP1, was associated with mRNA expression of 14 genes previously linked to fibrosis (P?.005). Conclusion: Development of subcutaneous fibrosis can be associated with genetic variation in the mitochondrial enzyme TXNRD2, critically involved in removal of ROS, and maintenance of the intracellular redox balance.

  18. Reactive oxygen species mediate Cr(VI)-induced carcinogenesis through PI3K/AKT-dependent activation of GSK-3β/β-catenin signaling

    SciTech Connect (OSTI)

    Son, Young-Ok; Pratheeshkumar, Poyil; Wang, Lei; Wang, Xin; Fan, Jia; Kim, Dong-Hern; Lee, Ju-Yeon; Zhang, Zhuo; Lee, Jeong-Chae; Shi, Xianglin

    2013-09-01

    Cr(VI) compounds are known human carcinogens that primarily target the lungs. Cr(VI) produces reactive oxygen species (ROS), but the exact effects of ROS on the signaling molecules involved in Cr(VI)-induced carcinogenesis have not been extensively studied. Chronic exposure of human bronchial epithelial cells to Cr(VI) at nanomolar concentrations (10–100 nM) for 3 months not only induced cell transformation, but also increased the potential of these cells to invade and migrate. Injection of Cr(VI)-stimulated cells into nude mice resulted in the formation of tumors. Chronic exposure to Cr(VI) increased levels of intracellular ROS and antiapoptotic proteins. Transfection with catalase or superoxide dismutase (SOD) prevented Cr(VI)-mediated increases in colony formation, cell invasion, migration, and xenograft tumors. While chronic Cr(VI) exposure led to activation of signaling cascades involving PI3K/AKT/GSK-3β/β-catenin and PI3K/AKT/mTOR, transfection with catalase or SOD markedly inhibited Cr(VI)-mediated activation of these signaling proteins. Inhibitors specific for AKT or β-catenin almost completely suppressed the Cr(VI)-mediated increase in total and active β-catenin proteins and colony formation. In particular, Cr(VI) suppressed autophagy of epithelial cells under nutrition deprivation. Furthermore, there was a marked induction of AKT, GSK-3β, β-catenin, mTOR, and carcinogenic markers in tumor tissues formed in mice after injection with Cr(VI)-stimulated cells. Collectively, our findings suggest that ROS is a key mediator of Cr(VI)-induced carcinogenesis through the activation of PI3K/AKT-dependent GSK-3β/β-catenin signaling and the promotion of cell survival mechanisms via the inhibition of apoptosis and autophagy. - Highlights: • Chronic exposure to Cr(VI) induces carcinogenic properties in BEAS-2B cells. • ROS play an important role in Cr(VI)-induced tumorigenicity of BEAS-2B cells. • PI3K/AKT/GSK-3β/β-catenin signaling involved in Cr

  19. Mechanical and photo-fragmentation processes for nanonization of melanin to improve its efficacy in protecting cells from reactive oxygen species stress

    SciTech Connect (OSTI)

    Liu, Yi-Cheng; Chen, Sih-Min; Liu, Jhong-Han; Hsu, Hsiang-Wei; Lin, Hoang-Yan; Chen, Szu-yuan

    2015-02-14

    It has been well established ex vivo that melanin has the ability of scavenging free radicals and reactive oxygen species (ROS), besides other functions. Therefore, we propose to utilize nanonized melanin as medication against acute oxidative stress. For this purpose, we developed and characterized two techniques based on mechanical stir and photo-fragmentation using femtosecond laser pulses, respectively, for disintegration of suspended melanin powder to produce nanometer-sized and water-dispersible melanin. This resolves a major obstacle in the medical and industrial applications of melanin. The viabilities of cultured retinal pigment epithelium (RPE) cells exposed to exogenous H{sub 2}O{sub 2} stress and treated with various conditions of melanin and irradiation were compared. It was found that melanin could be nanonized very effectively with the techniques, and nanonized melanin exhibited a much stronger effect than unprocessed melanin on raising the viability of cultured RPE cells under acute ROS stress. The effect was even more prominent without simultaneous light irradiation, promising for effective in vivo application to the whole body.

  20. Hydroxychavicol, a betel leaf component, inhibits prostate cancer through ROS-driven DNA damage and apoptosis

    SciTech Connect (OSTI)

    Gundala, Sushma Reddy; Yang, Chunhua; Mukkavilli, Rao; Paranjpe, Rutugandha; Brahmbhatt, Meera; Pannu, Vaishali; Cheng, Alice; Reid, Michelle D.; Aneja, Ritu

    2014-10-01

    Dietary phytochemicals are excellent ROS-modulating agents and have been shown to effectively enhance ROS levels beyond toxic threshold in cancer cells to ensure their selective killing while leaving normal cells unscathed. Here we demonstrate that hydroxychavicol (HC), extracted and purified from Piper betel leaves, significantly inhibits growth and proliferation via ROS generation in human prostate cancer, PC-3 cells. HC perturbed cell-cycle kinetics and progression, reduced clonogenicity and mediated cytotoxicity by ROS-induced DNA damage leading to activation of several pro-apoptotic molecules. In addition, HC treatment elicited a novel autophagic response as evidenced by the appearance of acidic vesicular organelles and increased expression of autophagic markers, LC3-IIb and beclin-1. Interestingly, quenching of ROS with tiron, an antioxidant, offered significant protection against HC-induced inhibition of cell growth and down regulation of caspase-3, suggesting the crucial role of ROS in mediating cell death. The collapse of mitochondrial transmembrane potential by HC further revealed the link between ROS generation and induction of caspase-mediated apoptosis in PC-3 cells. Our data showed remarkable inhibition of prostate tumor xenografts by ∼ 72% upon daily oral administration of 150 mg/kg bw HC by quantitative tumor volume measurements and non-invasive real-time bioluminescent imaging. HC was well-tolerated at this dosing level without any observable toxicity. This is the first report to demonstrate the anti-prostate cancer efficacy of HC in vitro and in vivo, which is perhaps attributable to its selective prooxidant activity to eliminate cancer cells thus providing compelling grounds for future preclinical studies to validate its potential usefulness for prostate cancer management. - Highlights: • HC perturbs cell-cycle progression by induction of reactive oxygen species (ROS). • HC mediated cytotoxicity by ROS-induced DNA damage leading to

  1. Cytotoxicity of InP/ZnS quantum dots related to reactive oxygen species generation.

    SciTech Connect (OSTI)

    Chibli, H.; Carlini, L.; Park, S.; Dimitrijevic, N. M.; Nadeau, J. L.

    2011-01-01

    Indium phosphide (InP) quantum dots (QDs) have emerged as a presumably less hazardous alternative to cadmium-based particles, but their cytotoxicity has not been well examined. Although their constituent elements are of very low toxicity to cells in culture, they nonetheless exhibit phototoxicity related to generation of reactive oxygen species by excited electrons and/or holes interacting with water and molecular oxygen. Using spin-trap electron paramagnetic resonance (EPR) spectroscopy and reporter assays, we find a considerable amount of superoxide and a small amount of hydroxyl radical formed under visible illumination of biocompatible InP QDs with a single ZnS shell, comparable to what is seen with CdTe. A double thickness shell reduces the reactive oxygen species concentration approximately two-fold. Survival assays in five cell lines correspondingly indicate a distinct reduction in toxicity with the double-shell InP QDs. Toxicity varies significantly across cell lines according to the efficiency of uptake, being overall significantly less than what is seen with CdTe or CdSe/ZnS. This indicates that InP QDs are a useful alternative to cadmium-containing QDs, while remaining capable of electron-transfer processes that may be undesirable or which may be exploited for photosensitization applications.

  2. Determination of reactive oxygen species from ZnO micro-nano structures with shape-dependent photocatalytic activity

    SciTech Connect (OSTI)

    He, Weiwei; Zhao, Hongxiao; Jia, Huimin; Yin, Jun-Jie; Zheng, Zhi

    2014-05-01

    Graphical abstract: ZnO micro/nano structures with shape dependent photocatalytic activity were prepared by hydrothermal reaction. The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were identified precisely by electron spin resonance spectroscopy. The type of reactive oxygen species was determined by band gap structure of ZnO. - Highlights: ZnO micro/nano structures with different morphologies were prepared by solvothermal reaction. Multi-pod like ZnO structures exhibited superior photocatalytic activity. The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were characterized precisely by electron spin resonance spectroscopy. The type of reactive oxygen species was determined by band gap structure of ZnO. - Abstract: ZnO micro/nano structures with different morphologies have been prepared by the changing solvents used during their synthesis by solvothermal reaction. Three typical shapes of ZnO structures including hexagonal, bell bottom like and multi-pod formed and were characterized by scanning electron microscopy and X-ray diffraction. Multi pod like ZnO structures exhibited the highest photocatalytic activity toward degradation of methyl orange. Using electron spin resonance spectroscopy coupled with spin trapping techniques, we demonstrate an effective way to identify precisely the generation of hydroxyl radicals, superoxide and singlet oxygen from the irradiated ZnO multi pod structures. The type of reactive oxygen species formed was predictable from the band gap structure of ZnO. These results indicate that the shape of micro-nano structures significantly affects the photocatalytic activity of ZnO, and demonstrate the value of electron spin resonance spectroscopy for characterizing the type of reactive oxygen species formed during photoexcitation of semiconductors.

  3. Cadmium-induced glutathionylation of actin occurs through a ROS-independent mechanism: Implications for cytoskeletal integrity

    SciTech Connect (OSTI)

    Choong, Grace; Liu, Ying; Xiao, Weiqun; Templeton, Douglas M.

    2013-10-15

    Cadmium disrupts the actin cytoskeleton in rat mesangial cells, and we have previously shown that this involves a complex interplay involving activation of kinase signaling, protein translocation, and disruption of focal adhesions. Here we investigate the role that glutathionylation of actin plays in Cd{sup 2+}-associated cytoskeletal reorganization. Low concentrations of Cd{sup 2+} (0.52 ?M) caused an increase in actin glutathionylation by 6 h, whereas at higher concentrations glutathionylation remained at basal levels. Although oxidation with diamide increased glutathionylation, reactive oxygen species (ROS) were not involved in the Cd{sup 2+}-dependent effect, as only Cd{sup 2+} concentrations above 2 ?M were sufficient to increase ROS. However, low [Cd{sup 2+}] increased total glutathione levels without affecting the ratio of reduced/oxidized glutathione, and inhibition of glutathione synthesis suppressed actin glutathionylation. Cadmium increased the activity of the enzyme glutaredoxin, which influences the equilibrium between glutathionylated and deglutathionylated proteins and thus may influence levels of glutathionylated actin. Together these observations show that cadmium-dependent effects on actin glutathionylation are affected by glutathione metabolism and not by direct effects of ROS on thiol chemistry. In vitro polymerization assays with glutathionylated actin show a decreased rate of polymerization. In contrast, immunofluorescence of cytoskeletal structure in intact cells suggests that increases in actin glutathionylation accompanying increased glutathione levels occurring under low Cd{sup 2+} exposure are protective in vivo, with cytoskeletal disruption ensuing only when higher Cd{sup 2+} concentrations increase ROS levels and prevent an increase in actinglutathione conjugates. - Highlights: Cadmium disrupts the actin cytoskeleton in mesangial cells. Cadmium induces glutathionylation of actin at low concentrations. Glutathionylation requires

  4. Impact of plasma jet vacuum ultraviolet radiation on reactive oxygen species generation in bio-relevant liquids

    SciTech Connect (OSTI)

    Jablonowski, H.; Hammer, M. U.; Reuter, S.; Bussiahn, R.; Weltmann, K.-D.; Woedtke, Th. von

    2015-12-15

    Plasma medicine utilizes the combined interaction of plasma produced reactive components. These are reactive atoms, molecules, ions, metastable species, and radiation. Here, ultraviolet (UV, 100–400 nm) and, in particular, vacuum ultraviolet (VUV, 10–200 nm) radiation generated by an atmospheric pressure argon plasma jet were investigated regarding plasma emission, absorption in a humidified atmosphere and in solutions relevant for plasma medicine. The energy absorption was obtained for simple solutions like distilled water (dH{sub 2}O) or ultrapure water and sodium chloride (NaCl) solution as well as for more complex ones, for example, Rosewell Park Memorial Institute (RPMI 1640) cell culture media. As moderate stable reactive oxygen species, hydrogen peroxide (H{sub 2}O{sub 2}) was studied. Highly reactive oxygen radicals, namely, superoxide anion (O{sub 2}{sup •−}) and hydroxyl radicals ({sup •}OH), were investigated by the use of electron paramagnetic resonance spectroscopy. All species amounts were detected for three different treatment cases: Plasma jet generated VUV and UV radiation, plasma jet generated UV radiation without VUV part, and complete plasma jet including all reactive components additionally to VUV and UV radiation. It was found that a considerable amount of radicals are generated by the plasma generated photoemission. From the experiments, estimation on the low hazard potential of plasma generated VUV radiation is discussed.

  5. Constitutive NF-?B activation and tumor-growth promotion by Romo1-mediated reactive oxygen species production

    SciTech Connect (OSTI)

    Chung, Jin Sil; Lee, Sora; Yoo, Young Do

    2014-08-08

    Highlights: Romo1 expression is required for constitutive nuclear DNA-binding activity of NF-?B. Romo1 depletion suppresses tumor growth in vivo. Romo1 presents a potential therapeutic target for diseases. - Abstract: Deregulation of nuclear factor-?B (NF-?B) and related pathways contribute to tumor cell proliferation and invasion. Mechanisms for constitutive NF-?B activation are not fully explained; however, the underlying defects appear to generate and maintain pro-oxidative conditions. In hepatocellular carcinoma (HCC) tissues, up-regulation of reactive oxygen species modulator 1 (Romo1) correlates positively with tumor size. In the present study, we showed that Romo1 expression is required to maintain constitutive nuclear DNA-binding activity of NF-?B and transcriptional activity through constitutive I?B? phosphorylation. Overexpression of Romo1 promoted p65 nuclear translocation and DNA-binding activity. We also show that Romo1 depletion suppressed anchorage-independent colony formation by HCC cells and suppressed tumor growth in vivo. Based on these findings, Romo1 may be a principal regulatory factor in the maintenance of constitutive NF-?B activation in tumor cells. In the interest of anti-proliferative treatments for cancer, Romo1 may also present a productive target for drug development.

  6. Knockdown of hepatoma-derived growth factor-related protein-3 induces apoptosis of H1299 cells via ROS-dependent and p53-independent NF-κB activation

    SciTech Connect (OSTI)

    Yun, Hong Shik; Baek, Jeong-Hwa; Yim, Ji-Hye; Lee, Su-Jae; Lee, Chang-Woo; Song, Jie-Young; Um, Hong-Duck; Park, Jong Kuk; Park, In-Chul; Hwang, Sang-Gu

    2014-07-11

    Highlights: • HRP-3 is a radiation- and anticancer drug-responsive protein in H1299 cells. • Depletion of HRP-3 induces apoptosis of radio- and chemoresistant H1299 cells. • Depletion of HRP-3 promotes ROS generation via inhibition of the Nrf2/HO-1 pathway. • ROS generation enhances NF-κB activity, which acts as an upstream signal in the c-Myc/Noxa apoptotic pathway. - Abstract: We previously identified hepatoma-derived growth factor-related protein-3 (HRP-3) as a radioresistant biomarker in p53 wild-type A549 cells and found that p53-dependent induction of the PUMA pathway was a critical event in regulating the radioresistant phenotype. Here, we found that HRP-3 knockdown regulates the radioresistance of p53-null H1299 cells through a distinctly different molecular mechanism. HRP-3 depletion was sufficient to cause apoptosis of H1299 cells by generating substantial levels of reactive oxygen species (ROS) through inhibition of the Nrf2/HO-1 antioxidant pathway. Subsequent, ROS-dependent and p53-independent NF-κB activation stimulated expression of c-Myc and Noxa proteins, thereby inducing the apoptotic machinery. Our results thus extend the range of targets for the development of new drugs to treat both p53 wild-type or p53-null radioresistant lung cancer cells.

  7. Moderate extracellular acidification inhibits capsaicin-induced cell death through regulating calcium mobilization, NF-{kappa}B translocation and ROS production in synoviocytes

    SciTech Connect (OSTI)

    Hu, Fen; Yang, Shuang; Zhao, Dan; Zhu, Shuyan; Wang, Yuxiang; Li, Junying

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer Moderate extracellular acidification regulates intracellular Ca{sup 2+} mobilization. Black-Right-Pointing-Pointer Moderate acidification activates NF-{kappa}B nuclear translocation in synoviocytes. Black-Right-Pointing-Pointer Moderate acidification depresses the ROS production induced by capsaicin. Black-Right-Pointing-Pointer Moderate acidification inhibits capsaicin-caused synoviocyte death. -- Abstract: We previously show the expression of transient receptor potential vanilloid 1 (TRPV1) in primary synoviocytes from collagen-induced arthritis (CIA) rats. Capsaicin and lowered extracellular pH from 7.4 to 5.5 induce cell death through TRPV1-mediated Ca{sup 2+} entry and reactive oxygen species (ROS) production. However, under the pathological condition in rheumatoid arthritis, the synovial fluid is acidified to a moderate level (about pH 6.8). In the present study, we examined the effects of pH 6.8 on the TRPV1-mediated cell death. Our finding is different or even opposite from what was observed at pH 5.5. We found that the moderate extracellular acidification (from pH 7.4 to 6.8) inhibited the capsaicin-induced Ca{sup 2+} entry through attenuating the activity of TRPV1. In the mean time, it triggered a phospholipse C (PLC)-related Ca{sup 2+} release from intracellular stores. The nuclear translocation of NF-{kappa}B was found at pH 6.8, and this also depends on PLC activation. Moreover, the capsaicin-evoked massive ROS production and cell death were depressed at pH 6.8, both of which are dependent on the activation of PLC and NF-{kappa}B. Taken together, these results suggested that the moderate extracellular acidification inhibited the capsaicin-induced synoviocyte death through regulating Ca{sup 2+} mobilization, activating NF-{kappa}B nuclear translocation and depressing ROS production.

  8. Cadmium induces carcinogenesis in BEAS-2B cells through ROS-dependent activation of PI3K/AKT/GSK-3β/β-catenin signaling

    SciTech Connect (OSTI)

    Son, Young-Ok; Wang, Lei; Poyil, Pratheeshkumar; Budhraja, Amit; Hitron, J. Andrew; Zhang, Zhuo; Lee, Jeong-Chae; School of Dentistry and Institute of Oral Biosciences , Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 ; Shi, Xianglin

    2012-10-15

    Cadmium has been widely used in industry and is known to be carcinogenic to humans. Although it is widely accepted that chronic exposure to cadmium increases the incidence of cancer, the mechanisms underlying cadmium-induced carcinogenesis are unclear. The main aim of this study was to investigate the role of reactive oxygen species (ROS) in cadmium-induced carcinogenesis and the signal transduction pathways involved. Chronic exposure of human bronchial epithelial BEAS-2B cells to cadmium induced cell transformation, as evidenced by anchorage-independent growth in soft agar and clonogenic assays. Chronic cadmium treatment also increased the potential of these cells to invade and migrate. Injection of cadmium-stimulated cells into nude mice resulted in the formation of tumors. In contrast, the cadmium-mediated increases in colony formation, cell invasion and migration were prevented by transfection with catalase, superoxide dismutase-1 (SOD1), or SOD2. In particular, chronic cadmium exposure led to activation of signaling cascades involving PI3K, AKT, GSK-3β, and β-catenin and transfection with each of the above antioxidant enzymes markedly inhibited cadmium-mediated activation of these signaling proteins. Inhibitors specific for AKT or β-catenin almost completely suppressed the cadmium-mediated increase in total and active β-catenin proteins and colony formation. Moreover, there was a marked induction of AKT, GSK-3β, β-catenin, and carcinogenic markers in tumor tissues formed in mice after injection with cadmium-stimulated cells. Collectively, our findings suggest a direct involvement of ROS in cadmium-induced carcinogenesis and implicate a role of AKT/GSK-3β/β-catenin signaling in this process. -- Highlights: ► Chronic exposure to cadmium induces carcinogenic properties in BEAS-2B cells. ► ROS involved in cadmium-induced tumorigenicity of BEAS-2B cells. ► Cadmium activates ROS-dependent AKT/GSK-3β/β-catenin-mediated signaling. ► ROS

  9. ROS and NF-{kappa}B are involved in upregulation of IL-8 in A549 cells exposed to multi-walled carbon nanotubes

    SciTech Connect (OSTI)

    Ye Shefang Wu Yihui; Hou Zhenqing; Zhang Qiqing

    2009-02-06

    Carbon nanotubes (CNTs) have potential applications in biosensors, tissue engineering, and biomedical devices because of their unique physico-chemical, electronic and mechanical properties. However, there is limited literature data available concerning the biological properties and toxicity of CNTs. This study aimed to assess the toxicity exhibited by multi-walled CNTs (MWCNTs) and to elucidate possible molecular mechanisms underlying the biological effects of MWCNTs in A549 cells. Exposing A549 cells to MWCNTs led to cell death, changes in cell size and complexity, reactive oxygen species (ROS) production, interleukin-8 (IL-8) gene expression and nuclear factor (NF)-{kappa}B activation. Treatment of A549 cells with antioxidants prior to adding MWCNTs decreased ROS production and abrogated expression of IL-8 mRNA. Pretreatment of A549 cells with NF-{kappa}B inhibitors suppressed MWCNTs-induced IL-8 mRNA expression. These results indicate that MWCNTs are able to induce expression of IL-8 in A549 cells, at least in part, mediated by oxidative stress and NF-{kappa}B activation.

  10. TGF-{beta}1 increases invasiveness of SW1990 cells through Rac1/ROS/NF-{kappa}B/IL-6/MMP-2

    SciTech Connect (OSTI)

    Binker, Marcelo G.; CBRHC Research Center, Buenos Aires ; Binker-Cosen, Andres A.; Gaisano, Herbert Y.; Cosen, Rodica H. de; Cosen-Binker, Laura I.

    2011-02-04

    Research highlights: {yields} Rac1 mediates TGF-{beta}1-induced SW1990 invasion through MMP-2 secretion and activation. {yields} NADPH-generated ROS act downstream of Rac1 in TGF-{beta}1-challenged SW1990 cells. {yields} TGF-{beta}1-stimulated ROS activate NF-{kappa}B in SW1990 cells. {yields} NF{kappa}B-induced IL-6 release is required for secretion and activation of MMP-2 in SW1990 cells. -- Abstract: Human pancreatic cancer invasion and metastasis have been found to correlate with increased levels of active matrix metalloproteinase 2 (MMP-2). The multifunctional cytokine transforming growth factor beta 1 (TGF-{beta}1) has been shown to increase both secretion of MMP-2 and invasion by several pancreatic cancer cell types. In the present study, we investigated the signaling pathway involved in TGF-{beta}1-promoted MMP-2 secretion and invasion by human pancreatic cancer cells SW1990. Using specific inhibitors, we found that stimulation of these tumor cells with TGF-{beta}1 induced secretion and activation of the collagenase MMP-2, which was required for TGF-{beta}1-stimulated invasion. Our results also indicate that signaling events involved in TGF-{beta}1-enhanced SW1990 invasiveness comprehend activation of Rac1 followed by generation of reactive oxygen species through nicotinamide adenine dinucleotide phosphate-oxidase, activation of nuclear factor-kappa beta, release of interleukin-6, and secretion and activation of MMP-2.

  11. Subneurotoxic copper(II)-induced NF-κB-dependent microglial activation is associated with mitochondrial ROS

    SciTech Connect (OSTI)

    Hu, Zhuqin; Yu, Fengxiang; Gong, Ping; Qiu, Yu; Zhou, Wei; Cui, Yongyao; Li, Juan Chen, Hongzhuan

    2014-04-15

    Microglia-mediated neuroinflammation and the associated neuronal damage play critical roles in the pathogenesis of neurodegenerative disorders. Evidence shows an elevated concentration of extracellular copper(II) in the brains of these disorders, which may contribute to neuronal death through direct neurotoxicity. Here we explored whether extracellular copper(II) triggers microglial activation. Primary rat microglia and murine microglial cell line BV-2 cells were cultured and treated with copper(II). The content of tumor necrosis factor-α (TNF-α) and nitric oxide in the medium was determined. Extracellular hydrogen peroxide was quantified by a fluorometric assay with Amplex Red. Mitochondrial superoxide was measured by MitoSOX oxidation. At subneurotoxic concentrations, copper(II) treatment induced a dose- and time-dependent release of TNF-α and nitric oxide from microglial cells, and caused an indirect, microglia-mediated neurotoxicity that was blocked by inhibition of TNF-α and nitric oxide production. Copper(II)-initiated microglial activation was accompanied with reduced IkB-α expression as well as phosphorylation and translocation of nuclear factor-κB (NF-κB) p65 and was blocked by NF-κB inhibitors (BAY11-7082 and SC-514). Moreover, copper(II) treatment evoked a rapid release of hydrogen peroxide from microglial cells, an effect that was not affected by NADPH oxidase inhibitors. N-acetyl-cysteine, a scavenger of reactive oxygen species (ROS), abrogated copper(II)-elicited microglial release of TNF-α and nitric oxide and subsequent neurotoxicity. Importantly, mitochondrial production of superoxide, paralleled to extracellular release of hydrogen peroxide, was induced after copper(II) stimulation. Our findings suggest that extracellular copper(II) at subneurotoxic concentrations could trigger NF-κB-dependent microglial activation and subsequent neurotoxicity. NADPH oxidase-independent, mitochondria-derived ROS may be involved in this activation

  12. Arsenic and chromium in drinking water promote tumorigenesis in a mouse colitis-associated colorectal cancer model and the potential mechanism is ROS-mediated Wnt/β-catenin signaling pathway

    SciTech Connect (OSTI)

    Wang, Xin; Mandal, Ardhendu K.; Saito, Hiroshi; Pulliam, Joseph F.; Lee, Eun Y.; Ke, Zun-Ji; Lu, Jian; Ding, Songze; Li, Li; Shelton, Brent J.; Tucker, Thomas; Evers, B. Mark; Zhang, Zhuo; Shi, Xianglin

    2012-07-01

    Exposure to carcinogenic metals, such as trivalent arsenic [As(III)] and hexavalent chromium [Cr(VI)], through drinking water is a major global public health problem and is associated with various cancers. However, the mechanism of their carcinogenicity remains unclear. In this study, we used azoxymethane/dextran sodium sulfate (AOM/DSS)-induced mouse colitis-associated colorectal cancer model to investigate their tumorigenesis. Our results demonstrate that exposure to As(III) or Cr(VI), alone or in combination, together with AOM/DSS pretreatment has a promotion effect, increasing the colorectal tumor incidence, multiplicity, size, and grade, as well as cell inflammatory response. Two-dimensional differential gel electrophoresis coupled with mass spectrometry revealed that As(III) or Cr(VI) treatment alone significantly changed the density of proteins. The expression of β-catenin and phospho-GSK was increased by treatment of carcinogenic metals alone. Concomitantly, the expression of NADPH oxidase1 (NOX1) and the level of 8-OHdG were also increased by treatment of carcinogenic metals alone. Antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, were decreased. Similarly, in an in vitro system, exposure of CRL-1807 to carcinogenic metals increased reactive oxygen species (ROS) generation, the expression of β-catenin, phospho-GSK, and NOX1. Inhibition of ROS generation by addition of SOD or catalase inhibited β-catenin expression and activity. Our study provides a new animal model to study the carcinogenicity of As(III) and Cr(VI) and suggests that As(III) and Cr(VI) promote colorectal cancer tumorigenesis, at least partly, through ROS-mediated Wnt/β-catenin signaling pathway. -- Highlights: ► Carcinogenic metals in drinking water promote colorectal tumor formation in vivo. ► Carcinogenic metals induce β-catenin activation in vivo and in vitro. ► ROS generation induced by carcinogenic metals mediated β-catenin activation.

  13. Cells with dysfunctional telomeres are susceptible to reactive oxygen species hydrogen peroxide via generation of multichromosomal fusions and chromosomal fragments bearing telomeres

    SciTech Connect (OSTI)

    Woo, Seon Rang; Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705 ; Park, Jeong-Eun; Juhn, Kyoung-Mi; Ju, Yeun-Jin; Jeong, Jaemin; Kang, Chang-Mo; Yun, Hyun Jin; Yun, Mi Yong; Shin, Hyun-Jin; Joo, Hyun-Yoo; Park, Eun-Ran; Park, In-Chul; Hong, Sung Hee; Hwang, Sang-Gu; Kim, Haekwon; Cho, Myung-Haing; Kim, Sang Hoon; Park, Gil Hong; Lee, Kee-Ho

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Under conditions of telomere erosion, cells become extremely sensitive to H{sub 2}O{sub 2}. Black-Right-Pointing-Pointer Chromosomal regions adjacent to telomeres are cleaved by H{sub 2}O{sub 2} under such conditions. Black-Right-Pointing-Pointer H{sub 2}O{sub 2} thus causes multichromosomal fusions and generation of small chromosomal fragments. Black-Right-Pointing-Pointer N-acetylcysteine prevents H{sub 2}O{sub 2}-induced chromosomal aberrations. -- Abstract: During genotoxic stress, reactive oxygen species hydrogen peroxide (H{sub 2}O{sub 2}) is a prime mediator of the DNA damage response. Telomeres function both to assist in DNA damage repair and to inhibit chromosomal end-to-end fusion. Here, we show that telomere dysfunction renders cells susceptible to H{sub 2}O{sub 2}, via generation of multichromosomal fusion and chromosomal fragments. H{sub 2}O{sub 2} caused formation of multichromosomal end-to-end fusions involving more than three chromosomes, preferentially when telomeres were erosive. Interestingly, extensive chromosomal fragmentation (yielding small-sized fragments) occurred only in cells exhibiting such multichromosomal fusions. Telomeres were absent from fusion points, being rather present in the small fragments, indicating that H{sub 2}O{sub 2} cleaves chromosomal regions adjacent to telomeres. Restoration of telomere function or addition of the antioxidant N-acetylcysteine prevented development of chromosomal aberrations and rescued the observed hypersensitivity to H{sub 2}O{sub 2}. Thus, chromosomal regions adjacent to telomeres become sensitive to reactive oxygen species hydrogen peroxide when telomeres are dysfunctional, and are cleaved to produce multichromosomal fusions and small chromosomal fragments bearing the telomeres.

  14. Changing national policy priorities and the ROS

    SciTech Connect (OSTI)

    Daschle, T.

    1994-12-31

    This paper discusses the effects of changing national policy priorities regarding the use of reformulated fuels and oxygenated fuels. The importance of the use of oxygenated fuels in reducing carbon monoxide pollution of the atmosphere and ways for people to work together to achieve this goal are discussed. MTBE and ETBE are important additives in the fuels industry and the economic outlook affecting their usage is briefly described.

  15. Perlick: ENERGY STAR Referral (HP48RO-S)

    Broader source: Energy.gov [DOE]

    DOE referred Perlick refrigerator HP48RO-S to EPA, brand manager of the ENERGY STAR program, for appropriate action after DOE testing revealed that the model does not meet ENERGY STAR requirements.

  16. Epithelialmesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanism in lung epithelial cells

    SciTech Connect (OSTI)

    Ding, Song-Ze; Yang, Yu-Xiu; Li, Xiu-Ling; Michelli-Rivera, Audrey; Han, Shuang-Yin; Wang, Lei; Pratheeshkumar, Poyil; Wang, Xin; Lu, Jian; Yin, Yuan-Qin; Budhraja, Amit; Hitron, Andrew J.

    2013-05-15

    Hexavalent chromium [Cr(VI)] is an important human carcinogen associated with pulmonary diseases and lung cancer. Exposure to Cr(VI) induces DNA damage, cell morphological change and malignant transformation in human lung epithelial cells. Despite extensive studies, the molecular mechanisms remain elusive, it is also not known if Cr(VI)-induced transformation might accompany with invasive properties to facilitate metastasis. We aimed to study Cr(VI)-induced epithelialmesenchymal transition (EMT) and invasion during oncogenic transformation in lung epithelial cells. The results showed that Cr(VI) at low doses represses E-cadherin mRNA and protein expression, enhances mesenchymal marker vimentin expression and transforms the epithelial cell into fibroblastoid morphology. Cr(VI) also increases cell invasion and promotes colony formation. Further studies indicated that Cr(VI) uses multiple mechanisms to repress E-cadherin expression, including activation of E-cadherin repressors such as Slug, ZEB1, KLF8 and enhancement the binding of HDAC1 in E-cadherin gene promoter, but DNA methylation is not responsible for the loss of E-cadherin. Catalase reduces Cr(VI)-induced E-cadherin and vimentin protein expression, attenuates cell invasion in matrigel and colony formation on soft agar. These results demonstrate that exposure to a common human carcinogen, Cr(VI), induces EMT and invasion during oncogenic transformation in lung epithelial cells and implicate in cancer metastasis and prevention. - Graphical abstract: Epithelialmesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanisms in lung epithelial cells. - Highlights: We study if Cr(VI) might induce EMT and invasion in epithelial cells. Cr(VI) induces EMT by altering E-cadherin and vimentin expression. It also increases cell invasion and promotes oncogenic transformation. Catalase reduces Cr(VI)-induced EMT, invasion and

  17. Oxygen analyzer

    DOE Patents [OSTI]

    Benner, William H.

    1986-01-01

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N.sub.2), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable oxygen obtained by decomposing the sample at 1135.degree. C., or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135.degree. C. as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N.sub.2, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  18. Oxygen analyzer

    DOE Patents [OSTI]

    Benner, W.H.

    1984-05-08

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N/sub 2/), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable obtained by decomposing the sample at 1135/sup 0/C, or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135/sup 0/C as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N/sub 2/, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  19. Reactive oxygen species produced by NADPH oxidase and mitochondrial dysfunction in lung after an acute exposure to Residual Oil Fly Ashes

    SciTech Connect (OSTI)

    Magnani, Natalia D.; Marchini, Timoteo; Vanasco, Virginia; Tasat, Deborah R.; Alvarez, Silvia; Evelson, Pablo

    2013-07-01

    Reactive O{sub 2} species production triggered by particulate matter (PM) exposure is able to initiate oxidative damage mechanisms, which are postulated as responsible for increased morbidity along with the aggravation of respiratory diseases. The aim of this work was to quantitatively analyse the major sources of reactive O{sub 2} species involved in lung O{sub 2} metabolism after an acute exposure to Residual Oil Fly Ashes (ROFAs). Mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight), and lung samples were analysed 1 h after instillation. Tissue O{sub 2} consumption and NADPH oxidase (Nox) activity were evaluated in tissue homogenates. Mitochondrial respiration, respiratory chain complexes activity, H{sub 2}O{sub 2} and ATP production rates, mitochondrial membrane potential and oxidative damage markers were assessed in isolated mitochondria. ROFA exposure was found to be associated with 61% increased tissue O{sub 2} consumption, a 30% increase in Nox activity, a 33% increased state 3 mitochondrial O{sub 2} consumption and a mitochondrial complex II activity increased by 25%. During mitochondrial active respiration, mitochondrial depolarization and a 53% decreased ATP production rate were observed. Neither changes in H{sub 2}O{sub 2} production rate, nor oxidative damage in isolated mitochondria were observed after the instillation. After an acute ROFA exposure, increased tissue O{sub 2} consumption may account for an augmented Nox activity, causing an increased O{sub 2}{sup ?} production. The mitochondrial function modifications found may prevent oxidative damage within the organelle. These findings provide new insights to the understanding of the mechanisms involving reactive O{sub 2} species production in the lung triggered by ROFA exposure. - Highlights: Exposure to ROFA alters the oxidative metabolism in mice lung. The augmented Nox activity contributes to the high tissue O{sub 2} consumption. Exposure to ROFA produces

  20. Direct Observation of the Oxygenated Species during Oxygen Reduction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The performance of polymer-electrolyte-membrane (PEM) fuel cells is limited by the ... The electrochemical cell has a polymer membrane, which serves as an electrolyte, coated on ...

  1. Inhibition of SH2-domain-containing inositol 5-phosphatase (SHIP2) ameliorates palmitate induced-apoptosis through regulating Akt/FOXO1 pathway and ROS production in HepG2 cells

    SciTech Connect (OSTI)

    Gorgani-Firuzjaee, Sattar; Adeli, Khosrow; Meshkani, Reza

    2015-08-21

    The serine–threonine kinase Akt regulates proliferation and survival by phosphorylating a network of protein substrates; however, the role of a negative regulator of the Akt pathway, the SH2-domain-containing inositol 5-phosphatase (SHIP2) in apoptosis of the hepatocytes, remains unknown. In the present study, we studied the molecular mechanisms linking SHIP2 expression to apoptosis using overexpression or suppression of SHIP2 gene in HepG2 cells exposed to palmitate (0.5 mM). Overexpression of the dominant negative mutant SHIP2 (SHIP2-DN) significantly reduced palmitate-induced apoptosis in HepG2 cells, as these cells had increased cell viability, decreased apoptotic cell death and reduced the activity of caspase-3, cytochrome c and poly (ADP-ribose) polymerase. Overexpression of the wild-type SHIP2 gene led to a massive apoptosis in HepG2 cells. The protection from palmitate-induced apoptosis by SHIP2 inhibition was accompanied by a decrease in the generation of reactive oxygen species (ROS). In addition, SHIP2 inhibition was accompanied by an increased Akt and FOXO-1 phosphorylation, whereas overexpression of the wild-type SHIP2 gene had the opposite effects. Taken together, these findings suggest that SHIP2 expression level is an important determinant of hepatic lipoapotosis and its inhibition can potentially be a target in treatment of hepatic lipoapoptosis in diabetic patients. - Highlights: • Lipoapoptosis is the major contributor to the development of NAFLD. • The PI3-K/Akt pathway regulates apoptosis in different cells. • The role of negative regulator of this pathway, SHIP2 in lipoapoptosis is unknown. • SHIP2 inhibition significantly reduces palmitate-induced apoptosis in HepG2 cells. • SHIP2 inhibition prevents palmitate induced-apoptosis by regulating Akt/FOXO1 pathway.

  2. Oxygen-producing inert anodes for SOM process

    DOE Patents [OSTI]

    Pal, Uday B

    2014-02-25

    An electrolysis system for generating a metal and molecular oxygen includes a container for receiving a metal oxide containing a metallic species to be extracted, a cathode positioned to contact a metal oxide housed within the container; an oxygen-ion-conducting membrane positioned to contact a metal oxide housed within the container; an anode in contact with the oxygen-ion-conducting membrane and spaced apart from a metal oxide housed within the container, said anode selected from the group consisting of liquid metal silver, oxygen stable electronic oxides, oxygen stable crucible cermets, and stabilized zirconia composites with oxygen stable electronic oxides.

  3. Artificial oxygen transport protein

    DOE Patents [OSTI]

    Dutton, P. Leslie

    2014-09-30

    This invention provides heme-containing peptides capable of binding molecular oxygen at room temperature. These compounds may be useful in the absorption of molecular oxygen from molecular oxygen-containing atmospheres. Also included in the invention are methods for treating an oxygen transport deficiency in a mammal.

  4. Sensitive Species

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sensitive Species Sensitive Species By avoiding or minimizing the impact of Laboratory activities on sensitive species, LANL can potentially reduce the possibility of these species being upgraded to federal protection. February 2, 2015 sensitive species The bald eagle is one of our sensitive species. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email Sensitive species are plants and animals that are protected at the state

  5. Identification of an Archean marine oxygen oasis

    SciTech Connect (OSTI)

    Riding, Dr Robert E; Fralick, Dr Philip; Liang, Liyuan

    2014-01-01

    The early Earth was essentially anoxic. A number of indicators suggest the presence of oxygenic photosynthesis 2700 3000 million years (Ma) ago, but direct evidence for molecular oxygen (O2) in seawater has remained elusive. Here we report rare earth element (REE) analyses of 2800 million year old shallowmarine limestones and deep-water iron-rich sediments at Steep Rock Lake, Canada. These show that the seawater from which extensive shallow-water limestones precipitated was oxygenated, whereas the adjacent deeper waters where iron-rich sediments formed were not. We propose that oxygen promoted limestone precipitation by oxidative removal of dissolved ferrous iron species, Fe(II), to insoluble Fe(III) oxyhydroxide, and estimate that at least 10.25 M oxygen concentration in seawater was required to accomplish this at Steep Rock. This agrees with the hypothesis that an ample supply of dissolved Fe(II) in Archean oceans would have hindered limestone formation. There is no direct evidence for the oxygen source at Steep Rock, but organic carbon isotope values and diverse stromatolites in the limestones suggest the presence of cyanobacteria. Our findings support the view that during the Archean significant oxygen levels first developed in protected nutrient-rich shallow marine habitats. They indicate that these environments were spatially restricted, transient, and promoted limestone precipitation. If Archean marine limestones in general reflect localized oxygenic removal of dissolved iron at the margins of otherwise anoxic iron-rich seas, then early oxygen oases are less elusive than has been assumed.

  6. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, F.H.; Chung, B.W.; Raistrick, I.D.; Brosha, E.L.

    1996-08-06

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer. 4 figs.

  7. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, Fernando H.; Chung, Brandon W.; Raistrick, Ian D.; Brosha, Eric L.

    1996-01-01

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer.

  8. Endangered Species

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Endangered Species Protecting our Endangered Species The Endangered Species Act requires that endangered species be protected at the individual level. February 2, 2015 Adult Mexican Spotted Owl Adult Mexican Spotted Owl recorded in 2010. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email The Habitat Management Plan details how threatened and endangered species and their habitats are managed at LANL. Endangered species on

  9. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, Fernando H.; Brosha, Eric L.

    1997-01-01

    A potentiometric oxygen sensor is formed having a logarithmic response to a differential oxygen concentration while operating as a Nernstian-type sensor. Very thin films of mixed conducting oxide materials form electrode services while permitting diffusional oxygen access to the interface between the zirconia electrolyte and the electrode. Diffusion of oxygen through the mixed oxide is not rate-limiting. Metal electrodes are not used so that morphological changes in the electrode structure do not occur during extended operation at elevated temperatures.

  10. Magnetic interaction in oxygenated alpha Fe-phthalocyanines

    SciTech Connect (OSTI)

    Kuzmann, Ern?, E-mail: kuzmann@caesar.elte.hu; Homonnay, Zoltn; Horvth, Attila [Institute of Chemistry, Etvs Lornd University, P.O. Box 32, 1512 Budapest (Hungary); Pechousek, Jiri; Cuda, Jan; Machala, Libor; Zoppellaro, Giorgio; Zboril, Radek [Regional Centre of Advanced Technologies and Materials, Departments of Experimental Physics and Physical Chemistry, Faculty of Science Palacky University, 17. Listopadu 1192/12, 771 46 Olomouc (Czech Republic); Yin, Houping; Wei, Yen [Department of Chemistry, Drexel University, Philadelphia, PA 19104 (United States); Klencsr, Zoltn [Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, 1117 (Hungary); Kubuki, Shiro [Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachi-Oji, Tokyo 192-0397 (Japan); Nath, Amar [Department of Chemistry, University of North Carolina, Asheville, NC 28804 (United States)

    2014-10-27

    Alpha iron phthalocyanines (?-FePc) oxygenated at low temperatures were investigated with the help of {sup 57}Fe Mssbauer spectroscopy, magnetization measurements (SQUID) and X-ray diffractometry (XRD). Mssbauer spectroscopy revealed that upon oxygenation of ?-FePc, new species were formed which could be associated with Fe{sup III}Pc oxygen adducts. Unexpectedly, magnetically split spectrum of oxygenated ?-FePc was observed below 20 K. In-field Mssbauer spectra in a 5 T external magnetic field at 5K and magnetization measurements indicate antiferromagnetic coupling in oxygenated ?-FePc.

  11. Oxygen partial pressure sensor

    DOE Patents [OSTI]

    Dees, D.W.

    1994-09-06

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured. 1 fig.

  12. Oxygen partial pressure sensor

    DOE Patents [OSTI]

    Dees, Dennis W.

    1994-01-01

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured.

  13. Eicosapentaenoic acid (EPA) induced apoptosis in HepG2 cells through ROSCa{sup 2+}JNK mitochondrial pathways

    SciTech Connect (OSTI)

    Zhang, Yuanyuan; Han, Lirong; Qi, Wentao; Cheng, Dai; Ma, Xiaolei; Hou, Lihua; Cao, Xiaohong; Wang, Chunling

    2015-01-24

    Highlights: EPA evoked ROS formation, [Ca{sup 2+}]{sub c} accumulation, the opening of MPTP and the phosphorylation of JNK. EPA-induced [Ca{sup 2+}]{sub c} elevation was depended on production of ROS. EPA-induced ROS generation, [Ca{sup 2+}]{sub c} increase, and JNK activated caused MPTP opening. The apoptosis induced by EPA was related to release of cytochrome C through the MPTP. EPA induced HepG2 cells apoptosis through ROSCa{sup 2+}JNK mitochondrial pathways. - Abstract: Eicosapentaenoic acid (EPA), a well-known dietary n?3 PUFAS, has been considered to inhibit proliferation of tumor cells. However, the molecular mechanism related to EPA-induced liver cancer cells apoptosis has not been reported. In this study, we investigated the effect of EPA on HepG2 cells proliferation and apoptosis mechanism through mitochondrial pathways. EPA inhibited proliferation of HepG2 cells in a dose-dependent manner and had no significant effect on the cell viability of humor normal liver L-02 cells. It was found that EPA initially evoked ROS formation, leading to [Ca{sup 2+}]{sub c} accumulation and the mitochondrial permeability transition pore (MPTP) opening; EPA-induced HepG2 cells apoptosis was inhibited by N-acetylcysteine (NAC, an inhibitor of ROS), 1,2-bis (2-aminophenoxy) ethane-N,N,N?,N?-tetraacetic acid (BAPTA-AM, a chelator of calcium) and CsA (inhibitor of MPTP). The relationship between ROS production, the increase of cytoplasmic Ca and MPTP opening was detected. It seems that ROS may act as an upstream regulator of EPA-induced [Ca{sup 2+}]{sub c} generation, moreover, generation of ROS, overload of mitochondrial [Ca{sup 2+}]{sub c}, and JNK activated cause the opening of MPTP. Western blotting results showed that EPA elevated the phosphorylation status of JNK, processes associated with the ROS generation. Simultaneously, the apoptosis induced by EPA was related to release of cytochrome C from mitochondria to cytoplasm through the MPTP and activation of

  14. Integrated turbomachine oxygen plant

    SciTech Connect (OSTI)

    Anand, Ashok Kumar; DePuy, Richard Anthony; Muthaiah, Veerappan

    2014-06-17

    An integrated turbomachine oxygen plant includes a turbomachine and an air separation unit. One or more compressor pathways flow compressed air from a compressor through one or more of a combustor and a turbine expander to cool the combustor and/or the turbine expander. An air separation unit is operably connected to the one or more compressor pathways and is configured to separate the compressed air into oxygen and oxygen-depleted air. A method of air separation in an integrated turbomachine oxygen plant includes compressing a flow of air in a compressor of a turbomachine. The compressed flow of air is flowed through one or more of a combustor and a turbine expander of the turbomachine to cool the combustor and/or the turbine expander. The compressed flow of air is directed to an air separation unit and is separated into oxygen and oxygen-depleted air.

  15. Oxygen ion conducting materials

    DOE Patents [OSTI]

    Carter, J. David; Wang, Xiaoping; Vaughey, John; Krumpelt, Michael

    2004-11-23

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  16. Oxygen ion conducting materials

    DOE Patents [OSTI]

    Vaughey, John; Krumpelt, Michael; Wang, Xiaoping; Carter, J. David

    2005-07-12

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  17. Oxygen ion conducting materials

    DOE Patents [OSTI]

    Vaughey, John; Krumpelt, Michael; Wang, Xiaoping; Carter, J. David

    2003-01-01

    An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

  18. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, F.H.; Brosha, E.L.

    1997-12-09

    A potentiometric oxygen sensor is formed having a logarithmic response to a differential oxygen concentration while operating as a Nernstian-type sensor. Very thin films of mixed conducting oxide materials form electrode services while permitting diffusional oxygen access to the interface between the zirconia electrolyte and the electrode. Diffusion of oxygen through the mixed oxide is not rate-limiting. Metal electrodes are not used so that morphological changes in the electrode structure do not occur during extended operation at elevated temperatures. 6 figs.

  19. Ethanol increases matrix metalloproteinase-12 expression via NADPH oxidase-dependent ROS production in macrophages

    SciTech Connect (OSTI)

    Kim, Mi Jin; Nepal, Saroj; Lee, Eung-Seok; Jeong, Tae Cheon; Kim, Sang-Hyun; Park, Pil-Hoon

    2013-11-15

    Matrix metalloproteinase-12 (MMP-12), an enzyme responsible for degradation of extracellular matrix, plays an important role in the progression of various diseases, including inflammation and fibrosis. Although most of those are pathogenic conditions induced by ethanol ingestion, the effect of ethanol on MMP-12 has not been explored. In the present study, we investigated the effect of ethanol on MMP-12 expression and its potential mechanisms in macrophages. Here, we demonstrated that ethanol treatment increased MMP-12 expression in primary murine peritoneal macrophages and RAW 264.7 macrophages at both mRNA and protein levels. Ethanol treatment also significantly increased the activity of nicotinamide adenine dinucleotide (NADPH) oxidase and the expression of NADPH oxidase-2 (Nox2). Pretreatment with an anti-oxidant (N-acetyl cysteine) or a selective inhibitor of NADPH oxidase (diphenyleneiodonium chloride (DPI)) prevented ethanol-induced MMP-12 expression. Furthermore, knockdown of Nox2 by small interfering RNA (siRNA) prevented ethanol-induced ROS production and MMP-12 expression in RAW 264.7 macrophages, indicating a critical role for Nox2 in ethanol-induced intracellular ROS production and MMP-12 expression in macrophages. We also showed that ethanol-induced Nox2 expression was suppressed by transient transfection with dominant negative IκB-α plasmid or pretreatment with Bay 11-7082, a selective inhibitor of NF-κB, in RAW 264.7 macrophages. In addition, ethanol-induced Nox2 expression was also attenuated by treatment with a selective inhibitor of p38 MAPK, suggesting involvement of p38 MAPK/NF-κB pathway in ethanol-induced Nox2 expression. Taken together, these results demonstrate that ethanol treatment elicited increase in MMP-12 expression via increase in ROS production derived from Nox2 in macrophages. - Highlights: • Ethanol increases ROS production through up-regulation of Nox2 in macrophages. • Enhanced oxidative stress contributes to ethanol

  20. High Selectivity Oxygen Delignification

    SciTech Connect (OSTI)

    Lucian A. Lucia

    2005-11-15

    Project Objective: The objectives of this project are as follows: (1) Examine the physical and chemical characteristics of a partner mill pre- and post-oxygen delignified pulp and compare them to lab generated oxygen delignified pulps; (2) Apply the chemical selectivity enhancement system to the partner pre-oxygen delignified pulps under mill conditions (with and without any predetermined amounts of carryover) to determine how efficiently viscosity is preserved, how well selectivity is enhanced, if strength is improved, measure any yield differences and/or bleachability differences; and (3) Initiate a mill scale oxygen delignification run using the selectivity enhancement agent, collect the mill data, analyze it, and propose any future plans for implementation.

  1. Optical oxygen concentration monitor

    DOE Patents [OSTI]

    Kebabian, P.

    1997-07-22

    A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest. 4 figs.

  2. Monolithic solid electrolyte oxygen pump

    DOE Patents [OSTI]

    Fee, Darrell C.; Poeppel, Roger B.; Easler, Timothy E.; Dees, Dennis W.

    1989-01-01

    A multi-layer oxygen pump having a one-piece, monolithic ceramic structure affords high oxygen production per unit weight and volume and is thus particularly adapted for use as a portable oxygen supply. The oxygen pump is comprised of a large number of small cells on the order of 1-2 millimeters in diameter which form the walls of the pump and which are comprised of thin, i.e., 25-50 micrometers, ceramic layers of cell components. The cell components include an air electrode, an oxygen electrode, an electrolyte and interconnection materials. The cell walls form the passages for input air and for exhausting the oxygen which is transferred from a relatively dilute gaseous mixture to a higher concentration by applying a DC voltage across the electrodes so as to ionize the oxygen at the air electrode, whereupon the ionized oxygen travels through the electrolyte and is converted to oxygen gas at the oxygen electrode.

  3. Optical oxygen concentration monitor

    DOE Patents [OSTI]

    Kebabian, Paul

    1997-01-01

    A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen's A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest.

  4. High pressure oxygen furnace

    DOE Patents [OSTI]

    Morris, D.E.

    1992-07-14

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized, the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 5 figs.

  5. High pressure oxygen furnace

    DOE Patents [OSTI]

    Morris, Donald E.

    1992-01-01

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  6. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-08-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the previous research, the reference point of oxygen occupancy was determined and verified. In the current research, the oxygen occupancy was investigated at 1200 C as a function of oxygen activity and compared with that at 1000 C. The cause of bumps at about 200 C was also investigated by using different heating and cooling rates during TGA. The fracture toughness of LSFT and dual phase membranes at room temperature is an important mechanical property. Vicker's indentation method was used to evaluate this toughness. Through this technique, a K{sub Ic} (Mode-I Fracture Toughness) value is attained by means of semi-empirical correlations between the indentation load and the length of the cracks emanating from the corresponding Vickers indentation impression. In the present investigation, crack propagation behavior was extensively analyzed in order to understand the strengthening mechanisms involved in the non-transforming La based ceramic composites. Cracks were generated using Vicker's indenter and used to identify and evaluate the toughening mechanisms involved. Preliminary results of an electron microscopy study of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Modeling of the isotopic transients on operating membranes (LSCrF-2828 at 900 C) and a ''frozen'' isotope profile have been analyzed in conjunction with a 1-D model to reveal the gradient in oxygen diffusivity through the membrane under conditions of high chemical gradients.

  7. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-02-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. The in situ electrical conductivity and Seebeck coefficient measurements were made on LSFT at 1000 and 1200 C over the oxygen activity range from air to 10{sup -15} atm. The electrical conductivity measurements exhibited a p to n type transition at an oxygen activity of 1 x 10{sup -10} at 1000 C and 1 x 10{sup -6} at 1200 C. Thermogravimetric studies were also carried out over the same oxygen activities and temperatures. Based on the results of these measurements, the chemical and mechanical stability range of LSFT were determined and defect structure was established. The studies on the fracture toughness of the LSFT and dual phase membranes exposed to air and N{sub 2} at 1000 C was done and the XRD and SEM analysis of the specimens were carried out to understand the structural and microstructural changes. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affect the mechanical properties. A complete transformation of fracture behavior was observed in the N{sub 2} treated LSFT samples. Further results to investigate the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Recent results on transient kinetic data are presented. The 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model is used to study ''frozen'' profiles in patterned or composite membranes.

  8. Fuel cell oxygen electrode

    DOE Patents [OSTI]

    Shanks, H.R.; Bevolo, A.J.; Danielson, G.C.; Weber, M.F.

    An oxygen electrode for a fuel cell utilizing an acid electrolyte has a substrate of an alkali metal tungsten bronze of the formula: A/sub x/WO/sub 3/ where A is an alkali metal and x is at least 0.2, which is covered with a thin layer of platinum tungsten bronze of the formula: Pt/sub y/WO/sub 3/ where y is at least 0.8.

  9. Fuel cell oxygen electrode

    DOE Patents [OSTI]

    Shanks, Howard R.; Bevolo, Albert J.; Danielson, Gordon C.; Weber, Michael F.

    1980-11-04

    An oxygen electrode for a fuel cell utilizing an acid electrolyte has a substrate of an alkali metal tungsten bronze of the formula: A.sub.x WO.sub.3 where A is an alkali metal and x is at least 0.2, which is covered with a thin layer of platinum tungsten bronze of the formula: Pt.sub.y WO.sub.3 where y is at least 0.8.

  10. Oxygen Transport Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay

    2008-08-30

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the

  11. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-02-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. Thermogravimetric analysis (TGA) was carried out on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} to investigate oxygen deficiency ({delta}) of the sample. The TGA was performed in a controlled atmosphere using oxygen, argon, carbon monoxide and carbon dioxide with adjustable gas flow rates. In this experiment, the weight loss and gain of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} was directly measured by TGA. The weight change of the sample was evaluated at between 600 and 1250 C in air or 1000 C as a function of oxygen partial pressure. The oxygen deficiencies calculated from TGA data as a function of oxygen activity and temperature will be estimated and compared with that from neutron diffraction measurement in air. The LSFT and LSFT/CGO membranes were fabricated from the powder obtained from Praxair Specialty Ceramics. The sintered membranes were subjected to microstructure analysis and hardness analysis. The LSFT membrane is composed of fine grains with two kinds of grain morphology. The grain size distribution was characterized using image analysis. In LSFT/CGO membrane a lot of grain pullout was observed from the less dense, porous phase. The hardness of the LSFT and dual phase membranes were studied at various loads. The hardness values obtained from the cross section of the membranes were also compared to that of the values obtained from the surface. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. Measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} as a function of temperature an oxygen partial pressure are reported. Further analysis of the dilatometry data obtained previously is presented. A series of isotope transients

  12. OXYGEN TRANSPORT CERAMIC MEMBRANES

    SciTech Connect (OSTI)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  13. Composite oxygen transport membrane

    DOE Patents [OSTI]

    Christie, Gervase Maxwell; Lane, Jonathan A.

    2014-08-05

    A method of producing a composite oxygen ion membrane and a composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1-xA.sub.x).sub.wCr.sub.1-yB.sub.yO.sub.3-.delta. and a doped zirconia. In the porous fuel oxidation layer and the optional porous surface exchange layer, A is Calcium and in the dense separation layer A is not Calcium and, preferably is Strontium. Preferred materials are (La.sub.0.8Ca.sub.0.2).sub.0.95Cr.sub.0.5Mn.sub.0.5O.sub.3-.delta. for the porous fuel oxidation and optional porous surface exchange layers and (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.5Fe.sub.0.5O.sub.3-.delta. for the dense separation layer. The use of such materials allows the membrane to sintered in air and without the use of pore formers to reduce membrane manufacturing costs. The use of materials, as described herein, for forming the porous layers have application for forming any type of porous structure, such as a catalyst support.

  14. High Selectivity Oxygen Delignification

    SciTech Connect (OSTI)

    Arthur J. Ragauskas Lucian A. Lucia Hasan Jameel

    2005-09-30

    The overall objective of this program was to develop improved extended oxygen delignification (EOD) technologies for current U.S. pulp mill operations. This was accomplished by: (1) Identifying pulping conditions that optimize O and OO performance; (2) Identifying structural features of lignin that enhance reactivity towards EOD of high kappa pulps; (3) Identifying factors minimizing carbohydrate degradation and improve pulp strength of EOD high kappa pulps; (4) Developing a simple, reproducible method of quantifying yield gains from EOD; and (5) Developing process conditions that significantly reduce the capital requirements of EOD while optimizing the yield benefits. Key research outcomes included, demonstrating the use of a mini-O sequence such as (E+O)Dkf:0.05(E+O) or Dkf:0.05(E+O)(E+O) without interstage washing could capture approximately 60% of the delignification efficiency of a conventional O-stage without the major capital requirements associated with an O-stage for conventional SW kraft pulps. The rate of formation and loss of fiber charge during an O-stage stage can be employed to maximize net fiber charge. Optimal fiber charge development and delignification are two independent parameters and do not parallel each other. It is possible to utilize an O-stage to enhance overall cellulosic fiber charge of low and high kappa SW kraft pulps which is beneficial for physical strength properties. The application of NIR and multi-variant analysis was developed into a rapid and simple method of determining the yield of pulp from an oxygen delignification stage that has real-world mill applications. A focus point of this program was the demonstration that Kraft pulping conditions and oxygen delignification of high and low-kappa SW and HW pulps are intimately related. Improved physical pulp properties and yield can be delivered by controlling the H-factor and active alkali charge. Low AA softwood kraft pulp with a kappa number 30 has an average improvement of 2% in

  15. Laser spectroscopy and dynamics of transient species

    SciTech Connect (OSTI)

    Clouthier, D.J.

    1993-12-01

    The goal of this program is to study the vibrational and electronic spectra and excited state dynamics of a number of transient sulfur and oxygen species. A variety of supersonic jet techniques, as well as high resolution FT-IR and intracavity dye laser spectroscopy, have been applied to these studies.

  16. Atomic oxygen patterning from a biomedical needle-plasma source

    SciTech Connect (OSTI)

    Kelly, Sen; Turner, Miles M.

    2013-09-28

    A plasma needle is a cold plasma source operating at atmospheric pressure. Such sources interact strongly with living cells, but experimental studies on bacterial samples show that this interaction has a surprising pattern resulting in circular or annular killing structures. This paper presents numerical simulations showing that this pattern occurs because biologically active reactive oxygen and nitrogen species are produced dominantly where effluent from the plasma needle interacts with ambient air. A novel solution strategy is utilised coupling plasma produced neutral (uncharged) reactive species to the gas dynamics solving for steady state profiles at the treated biological surface. Numerical results are compared with experimental reports corroborating evidence for atomic oxygen as a key bactericidal species. Surface losses are considered for interaction of plasma produced reactants with reactive solid and liquid interfaces. Atomic oxygen surface reactions on a reactive solid surface with adsorption probabilities above 0.1 are shown to be limited by the flux of atomic oxygen from the plasma. Interaction of the source with an aqueous surface showed hydrogen peroxide as the dominant species at this interface.

  17. Researchers Directly Observe Oxygen Signature in the Oxygen-evolving

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Complex of Photosynthesis Researchers Directly Observe Oxygen Signature in the Oxygen-evolving Complex of Photosynthesis Arguably the most important chemical reaction on earth is the photosynthetic splitting of water to molecular oxygen by the Mn-containing oxygen-evolving complex (Mn-OEC) in the protein known as photosystem II (PSII). It is this reaction which has, over the course of some 3.8 billion years, gradually filled our atmosphere with O2 and consequently enabled and sustained the

  18. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-05-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, in situ neutron diffraction was used to characterize the chemical and structural properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} (here after as L2SF55T) specimen, which was subject to measurements of neutron diffraction from room temperature to 900 C. It was found that space group of R3c yielded a better refinement than a cubic structure of Pm3m. Oxygen occupancy was nearly 3 in the region from room temperature to 700 C, above which the occupancy decreased due to oxygen loss. Dense OTM bars provided by Praxair were loaded to fracture at varying stress rates. Studies were done at room temperature in air and at 1000 C in a specified environment to evaluate slow crack growth behavior. The X-Ray data and fracture mechanisms points to non-equilibrium decomposition of the LSFCO OTM membrane. The non-equilibrium conditions could probably be due to the nature of the applied stress field (stressing rates) and leads to transition in crystal structures and increased kinetics of decomposition. The formations of a Brownmillerite or Sr2Fe2O5 type structures, which are orthorhombic are attributed to the ordering of oxygen vacancies. The cubic to orthorhombic transitions leads to 2.6% increase in strains and thus residual stresses generated could influence the fracture behavior of the OTM membrane. Continued investigations on the thermodynamic properties (stability and phase-separation behavior) and total conductivity of prototype membrane materials were carried out. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previously characterization, stoichiometry and conductivity measurements for samples of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} were reported. In this report

  19. Oxygenates from synthesis gas

    SciTech Connect (OSTI)

    Falter, W.; Keim, W.

    1994-12-31

    The direct synthesis of oxygenates starting from synthesis gas is feasible by homogeneous and heterogeneous catalysis. Homogeneous Rh and Ru based catalysts yielding methyl formate and alcohols will be presented. Interestingly, modified heterogeneous catalysts based on {open_quotes}Isobutyl Oel{close_quotes} catalysis, practized in Germany (BRD) up to 1952 and in the former DDR until recently, yield isobutanol in addition to methanol. These {open_quotes}Isobutyl Oel{close_quotes} catalysts are obtained by adding a base such as Li < Na < K < Cs to a Zn-Cr{sub 2}O{sub 3} methanol catalyst. Isobutanol is obtained in up to 15% yield. Our best catalyst a Zr-Zn-Mn-Li-Pd catalyst produced isobotanol up to 60% at a rate of 740g isobutanol per liter catalyst and hour.

  20. Oxygen-reducing catalyst layer

    DOE Patents [OSTI]

    O'Brien, Dennis P.; Schmoeckel, Alison K.; Vernstrom, George D.; Atanasoski, Radoslav; Wood, Thomas E.; Yang, Ruizhi; Easton, E. Bradley; Dahn, Jeffrey R.; O'Neill, David G.

    2011-03-22

    An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  1. MTBE, Oxygenates, and Motor Gasoline

    Gasoline and Diesel Fuel Update (EIA)

    MTBE, Oxygenates, and Motor Gasoline Contents * Introduction * Federal gasoline product quality regulations * What are oxygenates? * Who gets gasoline with oxygenates? * Which areas get MTBE? * How much has been invested in MTBE production capacity? * What does new Ethanol capacity cost? * What would an MTBE ban cost? * On-line information resources * Endnotes * Summary of revisions to this analysis Introduction The blending of methyl tertiary butyl ether (MTBE) into motor gasoline has increased

  2. EIA-819, Monthly Oxygenate Report ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (EIA) Form EIA-819, "Monthly Biofuel and Oxygenate Report," is used to collect data on ethanol production capacity, as well as stocks, receipts, inputs, production, and blending of...

  3. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-10-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, Moessbauer spectroscopy was used to study the local environmentals of LSFT with various level of oxygen deficiency. Ionic valence state, magnetic interaction and influence of Ti on superexchange are discussed Stable crack growth studies on Dense OTM bars provided by Praxair were done at elevated temperature, pressure and elevated conditions. Post-fracture X-ray data of the OTM fractured at 1000 C in environment were refined by FullProf code and results indicate a distortion of the parent cubic perovskite to orthorhombic structure with reduced symmetry. TGA-DTA studies on the post-fracture samples also indicated residual effect arising from the thermal and stress history of the samples. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. The initial measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} are reported. Neutron diffraction measurements of the same composition are in agreement with both the stoichiometry and the kinetic behavior observed in coulometric titration measurements. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The COCO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

  4. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    SciTech Connect (OSTI)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  5. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; W.B. Yelon; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-02-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and initial studies on newer composition of Ti doped LSF. Dense OTM bars provided by Praxair were loaded to fracture at varying stress rates. Studies were done at room temperature in air and at 1000 C in a specified environment to evaluate slow crack growth behavior. In addition, studies were also begun to obtain reliable estimates of fracture toughness and stable crack growth in specific environments. Newer composition of Ti doped LSF membranes were characterized by neutron diffraction analysis. Quench studies indicated an apparent correlation between the unit cell volume and oxygen occupancy. The studies however, indicated an anomaly of increasing Fe/Ti ratio with change in heat treatment. Ti doped LSF was also characterized for stoichiometry as a function of temp and pO{sub 2}. The non stoichiometry parameter {delta} was observed to increase almost linearly on lowering pO{sub 2} until a ideal stoichiometric composition of {delta} = 0.175 was approached.

  6. Oxygen detection using evanescent fields

    DOE Patents [OSTI]

    Duan, Yixiang; Cao, Weenqing

    2007-08-28

    An apparatus and method for the detection of oxygen using optical fiber based evanescent light absorption. Methylene blue was immobilized using a sol-gel process on a portion of the exterior surface of an optical fiber for which the cladding has been removed, thereby forming an optical oxygen sensor. When light is directed through the optical fiber, transmitted light intensity varies as a result of changes in the absorption of evanescent light by the methylene blue in response to the oxygen concentration to which the sensor is exposed. The sensor was found to have a linear response to oxygen concentration on a semi-logarithmic scale within the oxygen concentration range between 0.6% and 20.9%, a response time and a recovery time of about 3 s, ant to exhibit good reversibility and repeatability. An increase in temperature from 21.degree. C. to 35.degree. C. does not affect the net absorption of the sensor.

  7. Mixed oxygen ion/electron-conducting ceramics for oxygen separation

    SciTech Connect (OSTI)

    Stevenson, J.W.; Armstrong, B.L.; Armstrong, T.R.; Bates, J.L.; Pederson, L.R.; Weber, W.J.

    1995-05-01

    Solid mixed-conducting electrolytes in the series La{sub l-x}A{sub x}Co{sub l-y}Fe{sub y}O{sub 3-{delta}} (A = Sr,Ca,Ba) are potentially useful as passive membranes to separate high purity oxygen from air and as cathodes in fuel cells. All of the compositions studied exhibited very high electrical conductivities. At lower temperatures, conductivities increased with increasing temperature, characterized by activation energies of 0.05 to 0.16 eV that are consistent with a small polaron (localized electronic carrier) conduction mechanism. At higher temperatures, electronic conductivities tended to decrease with increasing temperature, which is attributed to decreased electronic carrier populations associated with lattice oxygen loss. Oxygen ion conductivities were higher than that of yttria stabilized zirconia and increased with the cobalt content and also increased with the extent of divalent A-site substitution. Thermogravimetric studies were conducted to establish the extent of oxygen vacancy formation as a function of temperature, oxygen partial pressure, and composition. These vacancy populations strongly depend on the extent of A-site substitution. Passive oxygen permeation rates were established for each of the compositions as a function of temperature and oxygen partial pressure gradient. For 2.5 mm thick membranes in an oxygen vs nitrogen partial pressure gradient, oxygen fluxes at 900 C ranged from approximately 0.3 sccm/cm{sup 2} for compositions high in iron and with low amounts of strontium A-site substitution to approximately 0.8 sccm/cm{sup 2} for compositions high in cobalt and strontium. A-site substitution with calcium instead of strontium resulted in substantially lower fluxes.

  8. A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines

    SciTech Connect (OSTI)

    Westbrook, C K; Pitz, W J; Curran, H J

    2005-11-14

    A detailed chemical kinetic modeling approach is used to examine the phenomenon of suppression of sooting in diesel engines by addition of oxygenated hydrocarbon species to the fuel. This suppression, which has been observed experimentally for a few years, is explained kinetically as a reduction in concentrations of soot precursors present in the hot products of a fuel-rich diesel ignition zone when oxygenates are included. Oxygenates decrease the overall equivalence ratio of the igniting mixture, producing higher ignition temperatures and more radical species to consume more soot precursor species, leading to lower soot production. The kinetic model is also used to show how different oxygenates, ester structures in particular, can have different soot-suppression efficiencies due to differences in molecular structure of the oxygenated species.

  9. Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them

    DOE Patents [OSTI]

    Schwartz, Michael; White, James H.; Sammells, Anthony F.

    2005-09-27

    This invention relates to gas-impermeable, solid state materials fabricated into membranes for use in catalytic membrane reactors. This invention particularly relates to solid state oxygen anion- and electron-mediating membranes for use in catalytic membrane reactors for promoting partial or full oxidation of different chemical species, for decomposition of oxygen-containing species, and for separation of oxygen from other gases. Solid state materials for use in the membranes of this invention include mixed metal oxide compounds having the brownmillerite crystal structure.

  10. Solid state oxygen anion and electron mediating membrane and catalytic membrane reactors containing them

    DOE Patents [OSTI]

    Schwartz, Michael; White, James H.; Sammels, Anthony F.

    2000-01-01

    This invention relates to gas-impermeable, solid state materials fabricated into membranes for use in catalytic membrane reactors. This invention particularly relates to solid state oxygen anion- and electron-mediating membranes for use in catalytic membrane reactors for promoting partial or full oxidation of different chemical species, for decomposition of oxygen-containing species, and for separation of oxygen from other gases. Solid state materials for use in the membranes of this invention include mixed metal oxide compounds having the brownmillerite crystal structure.

  11. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-11-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the current research, the electrical conductivity and Seebeck coefficient were measured as a function of temperature in air. Based on these measurements, the charge carrier concentration, net acceptor dopant concentration, activation energy of conduction and mobility were estimated. The studies on the fracture toughness of the LSFT and dual phase membranes at room temperature have been completed and reported previously. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affects the mechanical properties. To study the effect of temperature on the membranes when exposed to an inert environment, the membranes (LAFT and Dual phase) were heat treated at 1000 C in air and N{sub 2} atmosphere and hardness and fracture toughness of the membranes were studied after the treatment. The indentation method was used to find the fracture toughness and the effect of the heat treatment on the mechanical properties of the membranes. Further results on the investigation of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appears to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model will serve to study ''frozen'' profiles in patterned or composite membranes.

  12. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana

    2003-08-07

    In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/ Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Existing facilities were modified for evaluation of environmental assisted slow crack growth and creep in flexural mode. Processing of perovskites of LSC, LSF and LSCF composition were continued for evaluation of mechanical properties as a function of environment. These studies in parallel to those on the LSFCO composition is expect to yield important information on questions such as the role of cation segregation and the stability of the perovskite structure on crack initiation vs. crack growth. Studies have been continued on the La{sub 1-x}Sr{sub x}FeO{sub 3-d} composition using neutron diffraction and TGA studies. A transition from p-type to n-type of conductor was observed at relative low pO{sub 2}, at which the majority carriers changed from the holes to electrons because of the valence state decreases in Fe due to the further loss of oxygen. Investigation on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane transport. Data obtained at 850 C show that the stoichiometry in La{sub 0.2}Sr{sub 0.8}Fe{sub 0.8}Cr{sub 0.2}O{sub 3-x} vary from {approx}2.85 to 2.6 over the pressure range studied. From the stoichiometry a lower limit of 2.6 corresponding to the reduction of all Fe{sup 4+} to Fe{sup 3+} and no reduction of Cr{sup 3+} is expected.

  13. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; Thomas W. Eagar; Harold R. Larson; Raymundo Arroyave; X.-D Zhou; Y.-W. Shin; H.U. Anderson; Nigel Browning; Alan Jacobson; C.A. Mims

    2003-11-01

    The present quarterly report describes some of the initial studies on newer compositions and also includes newer approaches to address various materials issues such as in metal-ceramic sealing. The current quarter's research has also focused on developing a comprehensive reliability model for predicting the structural behavior of the membranes in realistic conditions. In parallel to industry provided compositions, models membranes have been evaluated in varying environment. Of importance is the behavior of flaws and generation of new flaws aiding in fracture. Fracture mechanics parameters such as crack tip stresses are generated to characterize the influence of environment. Room temperature slow crack growth studies have also been initiated in industry provided compositions. The electrical conductivity and defect chemistry of an A site deficient compound (La{sub 0.55}Sr{sub 0.35}FeO{sub 3}) was studied. A higher conductivity was observed for La{sub 0.55}Sr{sub 0.35}FeO{sub 3} than that of La{sub 0.60}Sr{sub 0.40}FeO{sub 3} and La{sub 0.80}Sr{sub 0.20}FeO{sub 3}. Defect chemistry analysis showed that it was primarily contributed by a higher carrier concentration in La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. Moreover, the ability for oxygen vacancy generation is much higher in La{sub 0.55}Sr{sub 0.35}FeO{sub 3} as well, which indicates a lower bonding strength between Fe-O and a possible higher catalytic activity for La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. The program continued to investigate the thermodynamic properties (stability and phase separation behavior) and total conductivity of prototype membrane materials. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previous report listed initial measurements on a sample of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-x} prepared in-house by Praxair. Subsequently, a second sample of powder from a larger batch of sample were characterized and compared with

  14. A lithium oxygen secondary battery

    SciTech Connect (OSTI)

    Semkow, K.W.; Sammells, A.F.

    1987-08-01

    In principle the lithium-oxygen couple should provide one of the highest energy densities yet investigated for advanced battery systems. The problem to this time has been one of identifying strategies for achieving high electrochemical reversibilities at each electrode under conditions where one might anticipate to also achieve long materials lifetimes. This has been addressed in recent work by us via the application of stabilized zirconia oxygen vacancy conducting solid electrolytes, for the effective separation of respective half-cell reactions.

  15. Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction Download presentation slides from the June 19, ...

  16. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-05-01

    the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The CO-CO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

  17. Instabilities in a capacitively coupled oxygen plasma

    SciTech Connect (OSTI)

    Küllig, C. Wegner, Th. Meichsner, J.

    2015-04-15

    Periodic fluctuations in the frequency range from 0.3 to 3 kHz were experimentally investigated in capacitively coupled radio frequency (13.56 MHz) oxygen plasma. The Gaussian beam microwave interferometry directly provides the line integrated electron density fluctuations. A system of two Langmuir probes measured the floating potential spatially (axial, radial) and temporally resolved. Hence, the floating potential fluctuation development is mapped within the discharge volume and provides a kind of discharge breathing and no wave propagation. Finally, it was measured the optical emission pattern of atomic oxygen during the fluctuation as well as the RF phase resolved optical emission intensity at selected phase position of the fluctuation by an intensified charge-coupled device camera. The deduced excitation rate pattern reveals the RF sheath dynamics and electron heating mechanisms, which is changing between low and high electronegativity during a fluctuation cycle. A perturbation calculation was taken into account using a global model with 15 elementary collision processes in the balance equations for the charged plasma species (O{sub 2}{sup +}, e, O{sup −}, O{sub 2}{sup −}) and a harmonic perturbation. The calculated frequencies agree with the experimentally observed frequencies. Whereby, the electron attachment/detachment processes are important for the generation of this instability.

  18. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-05-01

    been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The CO-CO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

  19. EVALUATING AN INNOVATIVE OXYGEN SENSOR FOR REMOTE SUBSURFACE OXYGEN MEASUREMENTS

    SciTech Connect (OSTI)

    Millings, M; Brian Riha, B; Warren Hyde, W; Karen Vangelas, K; Brian02 Looney, B

    2006-10-12

    Oxygen is a primary indicator of whether anaerobic reductive dechlorination and similar redox based processes contribute to natural attenuation remedies at chlorinated solvent contaminated sites. Thus, oxygen is a viable indicator parameter for documenting that a system is being sustained in an anaerobic condition. A team of researchers investigated the adaptation of an optical sensor that was developed for oceanographic applications. The optical sensor, because of its design and operating principle, has potential for extended deployment and sensitivity at the low oxygen levels relevant to natural attenuation. The results of the research indicate this tool will be useful for in situ long-term monitoring applications, but that the traditional characterization tools continue to be appropriate for characterization activities.

  20. Dilute Oxygen Combustion Phase I Final Report

    SciTech Connect (OSTI)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    1997-10-31

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions

  1. Dilute Oxygen Combustion Phase 2 Final Report

    SciTech Connect (OSTI)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    2005-09-30

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions

  2. Methods for separating oxygen from oxygen-containing gases

    DOE Patents [OSTI]

    Mackay, Richard; Schwartz, Michael; Sammells, Anthony F.

    2000-01-01

    This invention provides mixed conducting metal oxides particularly useful for the manufacture of catalytic membranes for gas-phase oxygen separation processes. The materials of this invention have the general formula: A.sub.x A'.sub.x A".sub.2-(x+x') B.sub.y B'.sub.y B".sub.2-(y+y') O.sub.5+z ; where x and x' are greater than 0; y and y' are greater than 0; x+x' is less than or equal to 2; y+y' is less than or equal to 2; z is a number that makes the metal oxide charge neutral; A is an element selected from the f block lanthanide elements; A' is an element selected from Be, Mg, Ca, Sr, Ba and Ra; A" is an element selected from the f block lanthanides or Be, Mg, Ca, Sr, Ba and Ra; B is an element selected from the group consisting of Al, Ga, In or mixtures thereof; and B' and B" are different elements and are independently selected from the group of elements Mg or the d-block transition elements. The invention also provides methods for oxygen separation and oxygen enrichment of oxygen deficient gases which employ mixed conducting metal oxides of the above formula. Examples of the materials used for the preparation of the membrane include A.sub.x Sr.sub.x' B.sub.y Fe.sub.y' Co.sub.2-(y+y') O.sub.5+z, where x is about 0.3 to about 0.5, x' is about 1.5 to about 1.7, y is 0.6, y' is between about 1.0 and 1.4 and B is Ga or Al.

  3. Electrochemical oxygen reduction catalysed by Ni3(hexaiminotriphenylene)2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Miner, Elise M.; Fukushima, Tomohiro; Sheberla, Dennis; Sun, Lei; Surendranath, Yogesh; Dinca, Mircea

    2016-03-08

    Control over the architectural and electronic properties of heterogeneous catalysts poses a major obstacle in the targeted design of active and stable non-platinum group metal electrocatalysts for the oxygen reduction reaction. Here we introduce Ni3(HITP)2 (HITP=2, 3, 6, 7, 10, 11-hexaiminotriphenylene) as an intrinsically conductive metal-organic framework which functions as a well-defined, tunable oxygen reduction electrocatalyst in alkaline solution. Ni3(HITP)2 exhibits oxygen reduction activity competitive with the most active non-platinum group metal electrocatalysts and stability during extended polarization. The square planar Ni-N4 sites are structurally reminiscent of the highly active and widely studied non-platinum group metal electrocatalysts containing M-N4 units.more » Ni3(HITP)2 and analogues thereof combine the high crystallinity of metal-organic frameworks, the physical durability and electrical conductivity of graphitic materials, and the diverse yet well-controlled synthetic accessibility of molecular species. As a result, such properties may enable the targeted synthesis and systematic optimization of oxygen reduction electrocatalysts as components of fuel cells and electrolysers for renewable energy applications.« less

  4. Catalyst containing oxygen transport membrane

    DOE Patents [OSTI]

    Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

    2012-12-04

    A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

  5. Composite oxygen ion transport element

    DOE Patents [OSTI]

    Chen, Jack C.; Besecker, Charles J.; Chen, Hancun; Robinson, Earil T.

    2007-06-12

    A composite oxygen ion transport element that has a layered structure formed by a dense layer to transport oxygen ions and electrons and a porous support layer to provide mechanical support. The dense layer can be formed of a mixture of a mixed conductor, an ionic conductor, and a metal. The porous support layer can be fabricated from an oxide dispersion strengthened metal, a metal-reinforced intermetallic alloy, a boron-doped Mo.sub.5Si.sub.3-based intermetallic alloy or combinations thereof. The support layer can be provided with a network of non-interconnected pores and each of said pores communicates between opposite surfaces of said support layer. Such a support layer can be advantageously employed to reduce diffusion resistance in any type of element, including those using a different material makeup than that outlined above.

  6. Oxygen-Enriched Combustion | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Oxygen-Enriched Combustion Oxygen-Enriched Combustion This tip sheet discusses how an increase in oxygen in combustion air can reduce the energy loss in the exhaust gases and increase process heating system efficiency. PROCESS HEATING TIP SHEET #3 Oxygen-Enriched Combustion (September 2005) (249.42 KB) More Documents & Publications Save Energy Now in Your Process Heating Systems Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A

  7. Oxygen transport in the internal xenon plasma of a dispenser hollow cathode

    SciTech Connect (OSTI)

    Capece, Angela M. Shepherd, Joseph E.; Polk, James E.; Mikellides, Ioannis G.

    2014-04-21

    Reactive gases such as oxygen and water vapor modify the surface morphology of BaO dispenser cathodes and degrade the electron emission properties. For vacuum cathodes operating at fixed temperature, the emission current drops rapidly when oxygen adsorbs on top of the low work function surface. Previous experiments have shown that plasma cathodes are more resistant to oxygen poisoning and can operate with O{sub 2} partial pressures one to two orders of magnitude higher than vacuum cathodes before the onset of poisoning occurs. Plasma cathodes used for electric thrusters are typically operated with xenon; however, gas phase barium, oxygen, and tungsten species may be found in small concentrations. The densities of these minor species are small compared with the plasma density, and thus, their presence in the discharge does not significantly alter the xenon plasma parameters. It is important, however, to consider the transport of these minor species as they may deposit on the emitter surface and affect the electron emission properties. In this work, we present the results of a material transport model used to predict oxygen fluxes to the cathode surface by solving the species conservation equations in a cathode with a 2.25?mm diameter orifice operated at a discharge current of 15?A, a Xe flow rate of 3.7 sccm, and 100?ppm of O{sub 2}. The dominant ionization process for O{sub 2} is resonant charge exchange with xenon ions. Ba is effectively recycled in the plasma; however, BaO and O{sub 2} are not. The model shows that the oxygen flux to the surface is not diffusion-limited; therefore, the high resistance to oxygen poisoning observed in plasma cathodes likely results from surface processes not considered here.

  8. California Endangered Species Act Species List | Open Energy...

    Open Energy Info (EERE)

    California Endangered Species Act Species List Jump to: navigation, search OpenEI Reference LibraryAdd to library Legal Document- OtherOther: California Endangered Species Act...

  9. Oxygen permeation and coal-gas-assisted hydrogen production using...

    Office of Scientific and Technical Information (OSTI)

    Oxygen permeation and coal-gas-assisted hydrogen production using oxygen transport membranes Citation Details In-Document Search Title: Oxygen permeation and coal-gas-assisted ...

  10. The mechanisms of oxygen reduction and evolution reactions in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and evolution reactions in nonaqueous lithium-oxygen batteries A mechanistic understanding of the oxygen reductionevolution reaction in non-aqueous lithium-oxygen batteries. ...

  11. Device and method for separating oxygen isotopes

    DOE Patents [OSTI]

    Rockwood, Stephen D.; Sander, Robert K.

    1984-01-01

    A device and method for separating oxygen isotopes with an ArF laser which produces coherent radiation at approximately 193 nm. The output of the ArF laser is filtered in natural air and applied to an irradiation cell where it preferentially photodissociates molecules of oxygen gas containing .sup.17 O or .sup.18 O oxygen nuclides. A scavenger such as O.sub.2, CO or ethylene is used to collect the preferentially dissociated oxygen atoms and recycled to produce isotopically enriched molecular oxygen gas. Other embodiments utilize an ArF laser which is narrowly tuned with a prism or diffraction grating to preferentially photodissociate desired isotopes. Similarly, desired mixtures of isotopic gas can be used as a filter to photodissociate enriched preselected isotopes of oxygen.

  12. Oxygen ion-beam microlithography

    DOE Patents [OSTI]

    Tsuo, Y. Simon

    1991-01-01

    A method of providing and developing a resist on a substrate for constructing integrated circuit (IC) chips includes the following steps: of depositing a thin film of amorphous silicon or hydrogenated amorphous silicon on the substrate and exposing portions of the amorphous silicon to low-energy oxygen ion beams to oxidize the amorphous silicon at those selected portions. The nonoxidized portions are then removed by etching with RF-excited hydrogen plasma. Components of the IC chip can then be constructed through the removed portions of the resist. The entire process can be performed in an in-line vacuum production system having several vacuum chambers. Nitrogen or carbon ion beams can also be used.

  13. Oxygen ion-beam microlithography

    DOE Patents [OSTI]

    Tsuo, Y.S.

    1991-08-20

    A method of providing and developing a resist on a substrate for constructing integrated circuit (IC) chips includes the following steps: of depositing a thin film of amorphous silicon or hydrogenated amorphous silicon on the substrate and exposing portions of the amorphous silicon to low-energy oxygen ion beams to oxidize the amorphous silicon at those selected portions. The nonoxidized portions are then removed by etching with RF-excited hydrogen plasma. Components of the IC chip can then be constructed through the removed portions of the resist. The entire process can be performed in an in-line vacuum production system having several vacuum chambers. Nitrogen or carbon ion beams can also be used. 5 figures.

  14. Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts on

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Stability-Low-Cost Supports | Department of Energy Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts on High-Stability-Low-Cost Supports Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts on High-Stability-Low-Cost Supports Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009 adzic_bnl_kickoff.pdf (4.62 MB) More Documents & Publications Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction

  15. Oxygen electrocatalysis on (001)-oriented manganese perovskite...

    Office of Scientific and Technical Information (OSTI)

    the nanoscale Citation Details In-Document Search Title: Oxygen electrocatalysis on (001)-oriented manganese perovskite films: Mn valency and charge transfer at the nanoscale ...

  16. DEVICE FOR CONTROL OF OXYGEN PARTIAL PRESSURE

    DOE Patents [OSTI]

    Bradner, H.; Gordon, H.S.

    1957-12-24

    A device is described that can sense changes in oxygen partial pressure and cause a corresponding mechanical displacement sufficient to actuate meters, valves and similar devices. A piston and cylinder arrangement contains a charge of crystalline metal chelate pellets which have the peculiar property of responding to variations in the oxygen content of the ambient atmosphere by undergoing a change in dimension. A lever system amplifies the relative displacement of the piston in the cylinder, and actuates the controlled valving device. This partial pressure oxygen sensing device is useful in controlled chemical reactions or in respiratory devices such as the oxygen demand meters for high altitude aircraft.

  17. Contiguous Platinum Monolayer Oxygen Reduction Electrocatalysts...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction Advanced Materials and Concepts for Portable Power Fuel Cells Catalysis Working ...

  18. Jupiter Oxygen Corporation | Open Energy Information

    Open Energy Info (EERE)

    Place: Schiller Park, Illinois Zip: 60176 Product: Illinois-based oxy-fuel combustion company involved in the capture of CO2. References: Jupiter Oxygen Corporation1...

  19. Homogeneously dispersed, multimetal oxygen-evolving catalysts...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Homogeneously dispersed, multimetal oxygen-evolving catalysts Citation ... Publication Date: 2016-03-24 OSTI Identifier: 1245398 Report ...

  20. New Oxygen-Production Technology Proving Successful

    Broader source: Energy.gov [DOE]

    The Office of Fossil Energy's National Energy Technology Laboratory has partnered with Air Products and Chemicals Inc. of Allentown, Penn. to develop the Ion Transport Membrane (ITM) Oxygen, a revolutionary new oxygen-production technology that requires less energy and offers lower capital costs than conventional technologies.

  1. Modelling Hydrogen Reduction and Hydrodeoxygenation of Oxygenates

    SciTech Connect (OSTI)

    Zhao, Y.; Xu, Q.; Cheah, S.

    2013-01-01

    Based on Density Functional Theory (DFT) simulations, we have studied the reduction of nickel oxide and biomass derived oxygenates (catechol, guaiacol, etc.) in hydrogen. Both the kinetic barrier and thermodynamic favorability are calculated with respect to the modeled reaction pathways. In early-stage reduction of the NiO(100) surface by hydrogen, the pull-off of the surface oxygen atom and simultaneous activation of the nearby Ni atoms coordinately dissociate the hydrogen molecules so that a water molecule can be formed, leaving an oxygen vacancy on the surface. In hydrogen reaction with oxygenates catalyzed by transition metals, hydrogenation of the aromatic carbon ring normally dominates. However, selective deoxygenation is of particular interest for practical application such as biofuel conversion. Our modeling shows that doping of the transition metal catalysts can change the orientation of oxygenates adsorbed on metal surfaces. The correlation between the selectivity of reaction and the orientation of adsorption are discussed.

  2. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2001-04-01

    This quarterly technical progress report will summarize work accomplished for the Program through the fourth quarter January-March 2001 in the following task areas: Task 1 - Oxygen Enhanced Combustion, Task 2 - Oxygen Transport Membranes and Task 4 - Program Management. This report will also recap the results of the past year. The program is proceeding in accordance with the objectives for the first year. OTM material characterization was completed. 100% of commercial target flux was demonstrated with OTM disks. The design and assembly of Praxair's single tube high-pressure test facility was completed. The production of oxygen with a purity of better than 99.5% was demonstrated. Coal combustion testing was conducted at the University of Arizona. Modest oxygen enhancement resulted in NOx emissions reduction. The injector for oxygen enhanced coal based reburning was conducted at Praxair. Combustion modeling with Keystone boiler was completed. Pilot-scale combustion test furnace simulations continued this quarter.

  3. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1996-01-01

    Preparation, structure, and properties of mixed metal oxide compositions containing at least strontium, cobalt, iron and oxygen are described. The crystalline mixed metal oxide compositions of this invention have, for example, structure represented by Sr.sub..alpha. (Fe.sub.1-x Co.sub.x).sub..alpha.+.beta. O.sub..delta. where x is a number in a range from 0.01 to about 1, .alpha. is a number in a range from about 1 to about 4, .beta. is a number in a range upward from 0 to about 20, and .delta. is a number which renders the compound charge neutral, and wherein the composition has a non-perovskite structure. Use of the mixed metal oxides in dense ceramic membranes which exhibit oxygen ionic conductivity and selective oxygen separation, are described as well as their use in separation of oxygen from an oxygen-containing gaseous mixture.

  4. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1997-01-01

    Preparation, structure, and properties of mixed metal oxide compositions containing at least strontium, cobalt, iron and oxygen are described. The crystalline mixed metal oxide compositions of this invention have, for example, structure represented by Sr.sub..alpha. (Fe.sub.1-x Co.sub.x).sub..alpha.+.beta. O.sub..delta. where x is a number in a range from 0.01 to about 1, .alpha. is a number in a range from about 1 to about 4, .beta. is a number in a range upward from 0 to about 20, and .delta. is a number which renders the compound charge neutral, and wherein the composition has a non-perovskite structure. Use of the mixed metal oxides in dense ceramic membranes which exhibit oxygen ionic conductivity and selective oxygen separation, are described as well as their use in separation of oxygen from an oxygen-containing gaseous mixture.

  5. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2004-04-01

    Conventional wisdom says adding oxygen to a combustion system enhances product throughput, system efficiency, and, unless special care is taken, increases NOx emissions. This increase in NOx emissions is typically due to elevated flame temperatures associated with oxygen use leading to added thermal NOx formation. Innovative low flame temperature oxy-fuel burner designs have been developed and commercialized to minimize both thermal and fuel NOx formation for gas and oil fired industrial furnaces. To be effective these systems require close to 100% oxy-fuel combustion and the cost of oxygen is paid for by fuel savings and other benefits. For applications to coal-fired utility boilers at the current cost of oxygen, however, it is not economically feasible to use 100% oxygen for NOx control. In spite of this conventional wisdom, Praxair and its team members, in partnership with the US Department of Energy National Energy Technology Laboratory, have developed a novel way to use oxygen to reduce NOx emissions without resorting to complete oxy-fuel conversion. In this concept oxygen is added to the combustion process to enhance operation of a low NOx combustion system. Only a small fraction of combustion air is replaced with oxygen in the process. By selectively adding oxygen to a low NOx combustion system it is possible to reduce NOx emissions from nitrogen-containing fuels, including pulverized coal, while improving combustion characteristics such as unburned carbon. A combination of experimental work and modeling was used to define how well oxygen enhanced combustion could reduce NOx emissions. The results of this work suggest that small amounts of oxygen replacement can reduce the NOx emissions as compared to the air-alone system. NOx emissions significantly below 0.15 lbs/MMBtu were measured. Oxygen addition was also shown to reduce carbon in ash. Comparison of the costs of using oxygen for NOx control against competing technologies, such as SCR, show that this

  6. Genomic definition of species

    SciTech Connect (OSTI)

    Crkvenjakov, R.; Drmanac, R.

    1991-07-01

    The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.

  7. Selective photooxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, Heinz; Blatter, Fritz; Sun, Hai

    1998-01-01

    A selective photooxidation process for the conversion of hydrocarbon molecules to partially oxygenated derivatives, which comprises the steps of adsorbing a hydrocarbon and oxygen onto a dehydrated zeolite support matrix to form a hydrocarbon-oxygen contact pair, and subsequently exposing the hydrocarbon-oxygen contact pair to visible light, thereby forming a partially oxygenated derivative.

  8. Petrochemical feedstock from basic oxygen steel furnace

    SciTech Connect (OSTI)

    Greenwood, C.W.; Hardwick, W.E.

    1983-10-01

    Iron bath gasification in which coal, lime, steam and oxygen are injected into a bath of molten iron for the production of a medium-Btu gas is described. The process has its origin in basic oxygen steelmaking. It operates at high temperatures and is thus not restrictive on the type of coal used. The ash is retained in the slag. The process is also very efficient. The authors suggest that in the present economic climate in the iron and steel industry, such a plant could be sited where existing coal-handling, oxygen and steelmaking equipment are available.

  9. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2003-08-01

    This quarterly technical progress report will summarize work accomplished for the Program through the thirteenth quarter, April-June 2003, in the following task areas: Task 1--Oxygen Enhanced Combustion, Task 3--Economic Evaluation and Task 4--Program Management. The program is proceeding in accordance with project objectives. REI's model was modified to evaluate mixing issues in the upper furnace of a staged unit. Analysis of the results, and their potential application to this unit is ongoing. Economic evaluation continues to confirm the advantage of oxygen-enhanced combustion. A contract for a commercial demonstration has been signed with the Northeast Generation Services Company to supply oxygen and license the oxygen enhanced low NOx combustor technology for use at the 147-megawatt coal fired Mt. Tom Station in Holyoke, MA. Commercial proposals have been submitted. Economic analysis of a beta site test performance was conducted.

  10. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam; Kleefisch, Mark S.; Kobylinski, Thaddeus P.; Morissette, Sherry L.; Pei, Shiyou

    1998-01-01

    Preparation, structure, and properties of mixed metal oxide compositions and their uses are described. Mixed metal oxide compositions of the invention have stratified crystalline structure identifiable by means of powder X-ray diffraction patterns. In the form of dense ceramic membranes, the present compositions demonstrate an ability to separate oxygen selectively from a gaseous mixture containing oxygen and one or more other volatile components by means of ionic conductivities.

  11. Luteolin inhibits Cr(VI)-induced malignant cell transformation of human lung epithelial cells by targeting ROS mediated multiple cell signaling pathways

    SciTech Connect (OSTI)

    Pratheeshkumar, Poyil; Son, Young-Ok; Divya, Sasidharan Padmaja; Roy, Ram Vinod; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Dai, Jin; Asha, Padmaja; Zhang, Zhuo; Wang, Yitao; Shi, Xianglin

    2014-12-01

    Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with the incidence of lung cancer. Inhibition of metal induced carcinogenesis by a dietary antioxidant is a novel approach. Luteolin, a natural dietary flavonoid found in fruits and vegetables, possesses potent antioxidant and anti-inflammatory activity. We found that short term exposure of human bronchial epithelial cells (BEAS-2B) to Cr(VI) (5 μM) showed a drastic increase in ROS generation, NADPH oxidase (NOX) activation, lipid peroxidation, and glutathione depletion, which were significantly inhibited by the treatment with luteolin in a dose dependent manner. Treatment with luteolin decreased AP-1, HIF-1α, COX-2, and iNOS promoter activity induced by Cr(VI) in BEAS-2B cells. In addition, luteolin protected BEAS-2B cells from malignant transformation induced by chronic Cr(VI) exposure. Moreover, luteolin also inhibited the production of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α) and VEGF in chronic Cr(VI) exposed BEAS-2B cells. Western blot analysis showed that luteolin inhibited multiple gene products linked to survival (Akt, Fak, Bcl-2, Bcl-xL), inflammation (MAPK, NF-κB, COX-2, STAT-3, iNOS, TNF-α) and angiogenesis (HIF-1α, VEGF, MMP-9) in chronic Cr(VI) exposed BEAS-2B cells. Nude mice injected with BEAS-2B cells chronically exposed to Cr(VI) in the presence of luteolin showed reduced tumor incidence compared to Cr(VI) alone treated group. Overexpression of catalase (CAT) or SOD2, eliminated Cr(VI)-induced malignant transformation. Overall, our results indicate that luteolin protects BEAS-2B cells from Cr(VI)-induced carcinogenesis by scavenging ROS and modulating multiple cell signaling mechanisms that are linked to ROS. Luteolin, therefore, serves as a potential chemopreventive agent against Cr(VI)-induced carcinogenesis. - Highlights: • Luteolin inhibited Cr(VI)-induced oxidative stress. • Luteolin inhibited chronic Cr(VI)-induced malignant transformation.

  12. Sodium orthovanadate associated with pharmacological doses of ascorbate causes an increased generation of ROS in tumor cells that inhibits proliferation and triggers apoptosis

    SciTech Connect (OSTI)

    Gnther, T-hat nia Mara Fischer; Kviecinski, Maicon Roberto; Baron, Carla Cristine; Felipe, Karina Bettega; Farias, Mirelle Sifroni; Ourique da Silva, Fabiana; Bcker, Ndia Cristina Falco; Pich, Claus Trger; Ferreira, Eduardo Antonio; Filho, Danilo Wilhelm; Verrax, Julien; Calderon, Pedro Buc; Pedrosa, Rozangela Curi

    2013-01-18

    Graphical abstract: -- Abstract: Pharmacological doses of ascorbate were evaluated for its ability to potentiate the toxicity of sodium orthovanadate (Na{sub 3}VO{sub 4}) in tumor cells. Cytotoxicity, inhibition of cell proliferation, generation of ROS and DNA fragmentation were assessed in T24 cells. Na{sub 3}VO{sub 4} was cytotoxic against T24 cells (EC{sub 50} = 5.8 ?M at 24 h), but in the presence of ascorbate (100 ?M) the EC{sub 50} fell to 3.3 ?M. Na{sub 3}VO{sub 4} plus ascorbate caused a strong inhibition of cell proliferation (up to 20%) and increased the generation of ROS (4-fold). Na{sub 3}VO{sub 4} did not directly cleave plasmid DNA, at this aspect no synergism was found occurring between Na{sub 3}VO{sub 4} and ascorbate once the resulting action of the combination was no greater than that of both substances administered separately. Cells from Ehrlich ascites carcinoma-bearing mice were used to determine the activity of antioxidant enzymes, the extent of the oxidative damage and the type of cell death. Na{sub 3}VO{sub 4} alone, or combined with ascorbate, increased catalase activity, but only Na{sub 3}VO{sub 4} plus ascorbate increased superoxide dismutase activity (up to 4-fold). Oxidative damage on proteins and lipids was higher due to the treatment done with Na{sub 3}VO{sub 4} plus ascorbate (23-fold). Ascorbate potentiated apoptosis in tumor cells from mice treated with Na{sub 3}VO{sub 4}. The results indicate that pharmacological doses of ascorbate enhance the generation of ROS induced by Na{sub 3}VO{sub 4} in tumor cells causing inhibition of proliferation and apoptosis. Apoptosis induced by orthovanadate and ascorbate is closer related to inhibition on Bcl-xL and activation of Bax. Our data apparently rule out a mechanism of cell demise p53-dependent or related to Cdk2 impairment.

  13. Magnetism in LithiumOxygen Discharge Product

    SciTech Connect (OSTI)

    Lu, Jun; Jung, Hun-Ji; Lau, Kah Chun; Zhang, Zhengcheng; Schlueter, John A.; Du, Peng; Assary, Rajeev S.; Greeley, Jeffrey P.; Ferguson, Glen A.; Wang, Hsien-Hau; Hassoun, Jusef; Iddir, Hakim; Zhou, Jigang; Zuin, Lucia; Hu, Yongfeng; Sun, Yang-Kook; Scrosati, Bruno; Curtiss, Larry A.; Amine, Khalil

    2013-05-13

    Nonaqueous lithiumoxygen batteries have a much superior theoretical gravimetric energy density compared to conventional lithium-ion batteries, and thus could render long-range electric vehicles a reality. A molecular-level understanding of the reversible formation of lithium peroxide in these batteries, the properties of major/minor discharge products, and the stability of the nonaqueous electrolytes is required to achieve successful lithiumoxygen batteries. We demonstrate that the major discharge product formed in the lithiumoxygen cell, lithium peroxide, exhibits a magnetic moment. These results are based on dc-magnetization measurements and a lithium oxygen cell containing an ether-based electrolyte. The results are unexpected because bulk lithium peroxide has a significant band gap. Density functional calculations predict that superoxide- type surface oxygen groups with unpaired electrons exist on stoichiometric lithium peroxide crystalline surfaces and on nanoparticle surfaces; these computational results are consistent with the magnetic measurement of the discharged lithium peroxide product as well as EPR measurements on commercial lithium peroxide. The presence of superoxide-type surface oxygen groups with spin can play a role in the reversible formation and decomposition of lithium peroxide as well as the reversible formation and decomposition of electrolyte molecules.

  14. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2002-01-01

    This quarterly technical progress report will summarize work accomplished for the Program in the seventh quarter October-December 2001 in the following task areas: Task 1 - Oxygen Enhanced Combustion, Task 2 - Oxygen Transport Membranes, Task 3 - Economic Evaluation and Task 4 - Program Management. Computational fluid dynamic (CFD) modeling of oxygen injection strategies was performed during the quarter resulting in data that suggest the oxygen injection reduces NOx emissions while reducing LOI. Pilot-scale testing activities concluded at the University of Utah this quarter. Testing demonstrated that some experimental conditions can lead to NOx emissions well below the 0.15 lb/MMBtu limit. Evaluation of alternative OTM materials with improved mechanical properties continued this quarter. Powder procedure optimization continued and sintering trial began on an element with a new design. Several OTM elements were tested in Praxair's single tube high-pressure test facility under various conditions. A modified PSO1d element demonstrated stable oxygen product purity of >98% and oxygen flux of 68% of target. Updated test results and projected economic performance have been reviewed with the Utility Industrial Advisors. The economic comparison remains very favorable for O{sub 2} enhanced combustion. Discussions regarding possible Beta sites have been held with three other utilities in addition to the industrial advisors. Proposals will be prepared after the completion of full scale burner testing. Beta test cost estimating work has been initiated.

  15. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2002-04-01

    This quarterly technical progress report will summarize work accomplished for the Program through the fourth quarter January-March 2002 in the following task areas: Task 1--Oxygen Enhanced Combustion, Task 2--Oxygen Transport Membranes, Task 3--Economic Evaluation and Task 4--Program Management. This report will also recap the results of the past year. The program is proceeding in accordance with the objectives for the second year. The first round of pilot scale testing with 3 bituminous coals was completed at the University of Utah. Full-scale testing equipment is in place and experiments are underway. Coal combustion lab-scale testing was completed at the University of Arizona. Modest oxygen enhancement resulted in NOx emissions reduction. Combustion modeling activities continued with pilot-scale combustion test furnace simulations. 75% of target oxygen flux was demonstrated with small PSO1 tube in Praxair's single tube high-pressure test facility. The production of oxygen with a purity of better than 99.999% was demonstrated. Economic evaluation has confirmed the advantage of oxygen-enhanced combustion. Two potential host sites have been identified.

  16. Direct determination of PB in gasoline emulsions using Ar and Ar-oxygen ICPs

    SciTech Connect (OSTI)

    Brenner, I.B.; Zander, A.; Shkolnik, J.; Kim, S.

    1995-12-31

    Lead in gasoline emulsions was determined by argon and argon-oxygen ICP-AES. Intensity variations of inorganic and organic lead species in aqueous solution and in gasoline and decalin emulsions were studied. In an aqueous solution Pb II intensities were higher than those observed in gasoline and decalin emulsions and were higher in the argon ICP than in an argon-oxygen plasma. Pb intensities were influenced by aerosol flow rate, oxygen doping and emulsion composition, which were all compensated by Y II the internal standard. Pb LODs in the emulsions were not significantly degraded relative to an aqueous solution, and were adequate for the direct determination of lead in gasoline at the mg/kg concentration. The accuracy of Pb determination in spiked gasoline emulsions and in NIST reference fuels was satisfactory. Mg II/Mg I ratios indicate that emulsion plasmas are similar to ICPs containing water only.

  17. Strain Control of Oxygen Vacancies in Epitaxial Strontium Cobaltite...

    Office of Scientific and Technical Information (OSTI)

    Strain Control of Oxygen Vacancies in Epitaxial Strontium Cobaltite Films Citation Details In-Document Search Title: Strain Control of Oxygen Vacancies in Epitaxial Strontium ...

  18. Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From...

    Open Energy Info (EERE)

    Oxygen And Carbon Isotope Ratios Of Hydrothermal Minerals From Yellowstone Drill Cores Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Oxygen...

  19. Virtual Oxygen Sensor for Innovative NOx and PM Emission Control...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Virtual Oxygen Sensor for Innovative NOx and PM Emission Control Technologies Virtual Oxygen Sensor for Innovative NOx and PM Emission Control Technologies A virtual O2 sensor for ...

  20. Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium 2007 Diesel Engine-Efficiency & ...

  1. Artificial oxygen transport protein (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Patent: Artificial oxygen transport protein Citation Details In-Document Search Title: Artificial oxygen transport protein This invention provides heme-containing peptides capable...

  2. Pt3Re alloy nanoparticles as electrocatalysts for the oxygen...

    Office of Scientific and Technical Information (OSTI)

    Pt3Re alloy nanoparticles as electrocatalysts for the oxygen reduction reaction Citation ... on March 24, 2018 Title: Pt3Re alloy nanoparticles as electrocatalysts for the oxygen ...

  3. Webinar: Testing Oxygen Reduction Reaction Activity with the...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Webinar: Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique Above is the video recording for the webinar, "Testing Oxygen Reduction Reaction ...

  4. Facile oxygen intercalation between full layer graphene and Ru...

    Office of Scientific and Technical Information (OSTI)

    Facile oxygen intercalation between full layer graphene and Ru(0001) under ambient ... Title: Facile oxygen intercalation between full layer graphene and Ru(0001) under ambient ...

  5. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    Lawrence E. Bool; Jack C. Chen; David R. Thompson

    2000-07-01

    Increased environmental regulations will require utility boilers to reduce NO{sub x} emissions to less than 0.15lb/MMBtu in the near term. Conventional technologies such as Selective Catalytic Reduction (SCR) and Selective Non-Catalytic Reduction (SNCR) are unable to achieve these lowered emission levels without substantially higher costs and major operating problems. Oxygen enhanced combustion is a novel technology that allows utilities to meet the NO{sub x} emission requirements without the operational problems that occur with SCR and SNCR. Furthermore, oxygen enhanced combustion can achieve these NO{sub x} limits at costs lower than conventional technologies. The objective of this program is to demonstrate the use of oxygen enhanced combustion as a technical and economical method of meeting the EPA State Implementation Plan for NO{sub x} reduction to less than 0.15lb/MMBtu for a wide range of boilers and coal. The oxygen enhanced coal combustion program (Task 1) focused this quarter on the specific objective of exploration of the impact of oxygen enrichment on NO{sub x} formation utilizing small-scale combustors for parametric testing. Research efforts toward understanding any limitations to the applicability of the technology to different burners and fuels such as different types of coal are underway. The objective of the oxygen transport membrane (OTM) materials development program (Task 2.1) is to ascertain a suitable material composition that can be fabricated into dense tubes capable of producing the target oxygen flux under the operating conditions. This requires that the material have sufficient oxygen permeation resulting from high oxygen ion conductivity, high electronic conductivity and high oxygen surface exchange rate. The OTM element development program (Task 2.2) objective is to develop, fabricate and characterize OTM elements for laboratory and pilot reactors utilizing quality control parameters to ensure reproducibility and superior performance

  6. Gene expression responses of HeLa cells to chemical species generated by an atmospheric plasma flow

    SciTech Connect (OSTI)

    Yokoyama, Mayo; Johkura, Kohei; Sato, Takehiko

    2014-08-08

    Highlights: • Response of HeLa cells to a plasma-irradiated medium was revealed by DNA microarray. • Gene expression pattern was basically different from that in a H{sub 2}O{sub 2}-added medium. • Prominently up-/down-regulated genes were partly shared by the two media. • Gene ontology analysis showed both similar and different responses in the two media. • Candidate genes involved in response to ROS were detected in each medium. - Abstract: Plasma irradiation generates many factors able to affect the cellular condition, and this feature has been studied for its application in the field of medicine. We previously reported that hydrogen peroxide (H{sub 2}O{sub 2}) was the major cause of HeLa cell death among the chemical species generated by high level irradiation of a culture medium by atmospheric plasma. To assess the effect of plasma-induced factors on the response of live cells, HeLa cells were exposed to a medium irradiated by a non-lethal plasma flow level, and their gene expression was broadly analyzed by DNA microarray in comparison with that in a corresponding concentration of 51 μM H{sub 2}O{sub 2}. As a result, though the cell viability was sufficiently maintained at more than 90% in both cases, the plasma-medium had a greater impact on it than the H{sub 2}O{sub 2}-medium. Hierarchical clustering analysis revealed fundamentally different cellular responses between these two media. A larger population of genes was upregulated in the plasma-medium, whereas genes were downregulated in the H{sub 2}O{sub 2}-medium. However, a part of the genes that showed prominent differential expression was shared by them, including an immediate early gene ID2. In gene ontology analysis of upregulated genes, the plasma-medium showed more diverse ontologies than the H{sub 2}O{sub 2}-medium, whereas ontologies such as “response to stimulus” were common, and several genes corresponded to “response to reactive oxygen species.” Genes of AP-1 proteins, e.g., JUN

  7. Oxygen generator for medical applications (USIC)

    SciTech Connect (OSTI)

    Staiger, C. L.

    2012-03-01

    The overall Project objective is to develop a portable, non-cryogenic oxygen generator capable of supplying medical grade oxygen at sufficient flow rates to allow the field application of the Topical Hyperbaric Oxygen Therapy (THOT{reg_sign}) developed by Numotech, Inc. This project was sponsored by the U.S. Department of Energy Global Initiatives for Proliferation Prevention (GIPP) and is managed by collaboration between Sandia National Laboratories (SNL), Numotech, Inc, and LLC SPE 'Spektr-Conversion.' The project had two phases, with the objective of Phase I being to develop, build and test a laboratory prototype of the membrane-pressure swing adsorber (PSA) system producing at 15 L/min of oxygen with a minimum of 98% oxygen purity. Phase II objectives were to further refine and identify the pre-requisites needed for a commercial product and to determine the feasibility of producing 15 L/min of oxygen with a minimum oxygen purity of 99%. In Phase I, Spektr built up the necessary infrastructure to perform experimental work and proceeded to build and demonstrate a membrane-PSA laboratory prototype capable of producing 98% purity oxygen at a flow rate of 5 L/min. Spektr offered a plausible path to scale up the process for 15 L/min. Based on the success and experimental results obtained in Phase I, Spektr performed work in three areas for Phase II: construction of a 15 L/min PSA; investigation of compressor requirements for the front end of the membrane/PSA system; and performing modeling and simulation of assess the feasibility of producing oxygen with a purity greater than 99%. Spektr successfully completed all of the tasks under Phase II. A prototype 15 L/min PSA was constructed and operated. Spektr determined that no 'off the shelf' air compressors met all of the specifications required for the membrane-PSA, so a custom compressor will likely need to be built. Modeling and simulation concluded that production of oxygen with purities greater than 99% was possible

  8. A dominant role of oxygen additive on cold atmospheric-pressure He + O{sub 2} plasmas

    SciTech Connect (OSTI)

    Yang, Aijun; Liu, Dingxin E-mail: xhw@mail.xjtu.edu.cn; Rong, Mingzhe; Wang, Xiaohua E-mail: xhw@mail.xjtu.edu.cn; Kong, Michael G.

    2014-08-15

    We present in this paper how oxygen additive impacts on the cold atmospheric-pressure helium plasmas by means of a one-dimensional fluid model. For the oxygen concentration [O{sub 2}]?>??0.1%, the influence of oxygen on the electron characteristics and the power dissipation becomes important, e.g., the electron density, the electron temperature in sheath, the electron-coupling power, and the sheath width decreasing by 1.6 to 16 folds with a two-log increase in [O{sub 2}] from 0.1% to 10%. Also the discharge mode evolves from the ? mode to the ? mode. The reactive oxygen species are found to peak in the narrow range of [O{sub 2}]?=?0.4%0.9% in the plasmas, similar to their power-coupling values. This applies to their wall fluxes except for those of O* and O{sub 2}{sup ?}. These two species have very short lifetimes, thus only when generated in boundary layers within several micrometers next to the electrode can contribute to the fluxes. The dominant reactive oxygen species and the corresponding main reactions are schematically presented, and their relations are quantified for selected applications.

  9. EO 13112: Invasive Species | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EO 13112: Invasive Species EO 13112: Invasive Species Establishment of the Invasive Species Council PDF icon EO 13112: Invasive Species More Documents & Publications EO 13089 -- ...

  10. Taurine protects HK-2 cells from oxidized LDL-induced cytotoxicity via the ROS-mediated mitochondrial and p53-related apoptotic pathways

    SciTech Connect (OSTI)

    Chang, Chun-Yu; Shen, Chao-Yu; Kang, Chao-Kai; Sher, Yuh-Pyng; Sheu, Wayne H.-H.; Chang, Chia-Che; Lee, Tsung-Han

    2014-09-15

    Oxidized LDL (oxLDL) induces a pro-oxidative environment and promotes apoptosis, causing the progression of renal diseases in humans. Taurine is a semi-essential amino acid in mammals and has been shown to be a potent endogenous antioxidant. The kidney plays a pivotal role in maintaining the balance of taurine. However, the mechanisms underlying the protective effects of taurine against oxLDL-induced injury in renal epithelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effects of taurine on human proximal tubular epithelial (HK-2) cells exposed to oxLDL and explored the related mechanisms. We observed that oxLDL increased the contents of ROS and of malondialdehyde (MDA), which is a lipid peroxidation by-product that acts as an indicator of the cellular oxidation status. In addition, oxLDL induced cell death and apoptosis in HK-2 cells. Pretreatment with taurine at 100 μM significantly attenuated the oxLDL-induced cytotoxicity. We determined that oxLDL triggered the phosphorylation of ERK and, in turn, the activation of p53 and other apoptosis-related events, including calcium accumulation, destabilization of the mitochondrial permeability and disruption of the balance between pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins. The malfunctions induced by oxLDL were effectively blocked by taurine. Thus, our results suggested that taurine exhibits potential therapeutic activity by preventing oxLDL-induced nephrotoxicity. The inhibition of oxLDL-induced epithelial apoptosis by taurine was at least partially due to its anti-oxidant activity and its ability to modulate the ERK and p53 apoptotic pathways. - Highlights: • Oxidized LDL induced cytotoxicity and apoptosis in HK-2 cells. • Pretreatment with taurine attenuated oxLDL-induced nephrotoxicity. • Taurine protected against renal damages through inhibition of ROS generation. • Taurine prevented apoptosis through modulation of the p53 phosphorylation.

  11. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Florida)

    SciTech Connect (OSTI)

    Zale, A.V.; Merrifield, S.G. )

    1989-07-01

    Species profiles are literature summaries of the taxonomy, morphology, distribution, life history, habitats, and environmental requirements of coastal species of fishes and aquatic invertebrates. They are designed to assist in environmental impact assessment. The tarpon and ladyfish are popular gamefishes. Adults spawn offshore. Larval and juvenile stages inhabit coastal marshes and mangroves. Both species are thermophilic (preferring warm water), euryhaline (tolerant of a wide range of salinity), and are capable of surviving at low oxygen concentrations. Wetlands destruction and degradation negatively affect these species by reducing nursery areas. 3 figs.

  12. Dynamic ESR study of oxygen chemisorption on TiO[sub 2]-based catalysts

    SciTech Connect (OSTI)

    Qin, D.; Chang, W.; Chen, Y.; Zhou, J.; Chen, Y.; Gong, M. )

    1993-08-01

    The process of methane oxidative coupling (MOC) is promising for the development of methane-based industries. Many papers exist on the preparation of catalysts and the mechanism of the reaction. In the MOC reaction, methane is supposed to be activated through abstraction of an H atom from CH[sub 4] by an active oxygen species. Lunsford and his co-workers detected (Li[sup +]O[sup [minus

  13. FWS - Candidate Species List under the Endangered Species Act...

    Open Energy Info (EERE)

    what a candidate species is under Section 4 of the Endangered Species Act. Author U.S. Fish and Wildlife Service Published U.S. Fish and Wildlife Service, 2011 DOI Not Provided...

  14. EO 13112: Invasive Species

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Presidential Documents 6183 Federal Register / Vol. 64, No. 25 / Monday, February 8, 1999 / Presidential Documents Executive Order 13112 of February 3, 1999 Invasive Species By the authority vested in me as President by the Constitution and the laws of the United States of America, including the National Environmental Policy Act of 1969, as amended (42 U.S.C. 4321 et seq.), Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990, as amended (16 U.S.C. 4701 et seq.), Lacey Act, as

  15. Singlet-Oxygen Generation From Individual Semiconducting and Metallic Nanostructures During Near-Infrared Laser Trapping

    SciTech Connect (OSTI)

    Smith, Bennett E.; Roder, Paden B.; Hanson, Jennifer L.; Manandhar, Sandeep; Devaraj, Arun; Perea, Daniel E.; Kim, Woo-Joong; Kilcoyne, Arthur L.; Pauzauskie, Peter J.

    2015-03-13

    Photodynamic therapy has been used for several decades in the treatment of solid tumors through the generation of reactive singlet-oxygen species (1O2). Recently, nanoscale metallic and semiconducting materials have been reported to act as photosensitizing agents with additional diagnostic and therapeutic functionality. To date there have been no reports of observing the generation of singlet-oxygen at the level of single nanostructures, particularly at near infrared (NIR) wavelengths. Here we demonstrate that NIR laser-tweezers can be used to observe the formation of singlet-oxygen produced from individual silicon and gold nanowires via use of a commercially available reporting dye. The laser trap also induces 2-photon photoexcitation of the dye following a chemical reaction with singlet oxygen. Corresponding 2-photon emission spectra confirms the generation of singlet oxygen from individual silicon nanowires at room temperature (30°C), suggesting a range of applications in understanding the impact of 1O2 on individual cancer cells.

  16. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2003-02-01

    This quarterly technical progress report will summarize work accomplished for the Program through the eleventh quarter, October-December 2002, in the following task areas: Task 1 - Oxygen Enhanced Combustion, Task 2 - Oxygen Transport Membranes, Task 3 - Economic Evaluation and Task 4 - Program Management. The program is proceeding in accordance with the objectives for the third year. Pilot scale experiments conducted at the University of Utah were aimed at confirming the importance of oxygen injection strategy for different types of burners. CFD modeling at REI was used to better understand the potential for increased corrosion under oxygen enhanced combustion conditions. Data from a full-scale demonstration test in Springfield, MO were analyzed. OTM element development continued with preliminary investigation of an alternative method of fabrication of PSO1d elements. OTM process development continued with long-term testing of a PSO1d element. Economic evaluation has confirmed the advantage of oxygen-enhanced combustion. Proposals have been submitted for two additional beta test sites. A first commercial proposal has been submitted. Economic analysis of a beta site test performance was conducted.

  17. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2003-04-01

    This quarterly technical progress report will summarize work accomplished for the Program through the twelfth quarter, January-March 2003, in the following task areas: Task 1--Oxygen Enhanced Combustion, Task 2--Oxygen Transport Membranes, Task 3--Economic Evaluation and Task 4--Program Management. The program is proceeding in accordance with the objectives for the third year. Pilot scale experiments conducted at the University of Utah explored both the effectiveness of oxygen addition and the best way to add oxygen with a scaled version of Riley Power's newest low NOx burner design. CFD modeling was done to compare the REI's modeling results for James River Unit 3 with the NOx and LOI results obtained during the demonstration program at that facility. Investigation of an alternative method of fabrication of PSO1d elements was conducted. OTM process development work has concluded with the completion of a long-term test of a PSO1d element Economic evaluation has confirmed the advantage of oxygen-enhanced combustion. Proposals have been submitted for two additional beta test sites. Commercial proposals have been submitted. Economic analysis of a beta site test performance was conducted.

  18. Oxygenates du`jour...MTBE? Ethanol? ETBE?

    SciTech Connect (OSTI)

    Wolfe, R.

    1995-12-31

    There are many different liquids that contain oxygen which could be blended into gasoline. The ones that have been tried and make the most sense are in the alcohol (R-OH) and ether (R-O-R) chemical family. The alcohols considered are: methanol (MeOH), ethanol (EtOH), tertiary butyl alcohol (TBA). The ethers are: methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), tertiary amyl ethyl ether (TAEE), di-isopropyl ether (DIPE). Of the eight oxygenates listed above, the author describes the five that are still waiting for widespread marketing acceptance (methanol, TBA, TAME, TAEE, and DIPE). He then discusses the two most widely used oxygenates in the US, MTBE and ethanol, along with the up-and-coming ethanol ether, ETBE. Selected physical properties for all of these oxygenates can be found in Table 2 at the end of this paper. A figure shows a simplified alcohol/ether production flow chart for the oxygenates listed above and how they are interrelated.

  19. Absorption process for producing oxygen and nitrogen and solution therefor

    DOE Patents [OSTI]

    Roman, I.C.; Baker, R.W.

    1990-09-25

    Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible. 1 figure

  20. Absorption process for producing oxygen and nitrogen and solution therefor

    DOE Patents [OSTI]

    Roman, Ian C. [Wilmington, DE; Baker, Richard W. [Palo Alto, CA

    1990-09-25

    Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible.

  1. Absorption process for producing oxygen and nitrogen and solution therefor

    DOE Patents [OSTI]

    Roman, Ian C.

    1984-01-01

    Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible.

  2. Oxygen reduction reaction: A framework for success

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Allendorf, Mark D.

    2016-05-06

    Oxygen reduction at the cathode of fuel cells typically requires a platinum-based material to catalyse the reaction, but lower-cost, more stable catalysts are sought. Here, an intrinsically conductive metal–organic framework based on cheaper elements is shown to be a durable, structurally well-defined catalyst for this reaction.

  3. Ammonia producing engine utilizing oxygen separation

    DOE Patents [OSTI]

    Easley, Jr., William Lanier; Coleman, Gerald Nelson; Robel, Wade James

    2008-12-16

    A power system is provided having a power source, a first power source section with a first intake passage and a first exhaust passage, a second power source section with a second intake passage and a second exhaust passage, and an oxygen separator. The second intake passage may be fluidly isolated from the first intake passage.

  4. Novel Membranes and Processes for Oxygen Enrichment

    SciTech Connect (OSTI)

    Lin, Haiqing

    2011-11-15

    The overall goal of this project is to develop a membrane process that produces air containing 25-35% oxygen, at a cost of $25-40/ton of equivalent pure oxygen (EPO2). Oxygen-enriched air at such a low cost will allow existing air-fueled furnaces to be converted economically to oxygen-enriched furnaces, which in turn will improve the economic and energy efficiency of combustion processes significantly, and reduce the cost of CO{sub 2} capture and sequestration from flue gases throughout the U.S. manufacturing industries. During the 12-month Concept Definition project: We identified a series of perfluoropolymers (PFPs) with promising oxygen/nitrogen separation properties, which were successfully made into thin film composite membranes. The membranes showed oxygen permeance as high as 1,200 gpu and oxygen/nitrogen selectivity of 3.0, and the permeance and selectivity were stable over the time period tested (60 days). We successfully scaled up the production of high-flux PFP-based membranes, using MTR's commercial coaters. Two bench-scale spiral-wound modules with countercurrent designs were made and parametric tests were performed to understand the effect of feed flow rate and pressure, permeate pressure and sweep flow rate on the membrane module separation properties. At various operating conditions that modeled potential industrial operating conditions, the module separation properties were similar to the pure-gas separation properties in the membrane stamps. We also identified and synthesized new polymers [including polymers of intrinsic microporosity (PIMs) and polyimides] with higher oxygen/nitrogen selectivity (3.5-5.0) than the PFPs, and made these polymers into thin film composite membranes. However, these membranes were susceptible to severe aging; pure-gas permeance decreased nearly six-fold within two weeks, making them impractical for industrial applications of oxygen enrichment. We tested the effect of oxygen-enriched air on NO{sub x} emissions using a

  5. Analysis of Oxygenated Compounds in Hydrotreated Biomass Fast Pyrolysis Oil Distillate Fractions

    SciTech Connect (OSTI)

    Christensen, Earl D.; Chupka, Gina; Luecke, Jon; Smurthwaite, Tricia D.; Alleman, Teresa L.; Iisa, Kristiina; Franz, James A.; Elliott, Douglas C.; McCormick, Robert L.

    2011-10-06

    Three hydrotreated bio-oils with different oxygen contents (8.2, 4.9, and 0.4 w/w) were distilled to produce Light, Naphtha, Jet, Diesel, and Gasoil boiling range fractions that were characterized for oxygen containing species by a variety of analytical methods. The bio-oils were originally generated from lignocellulosic biomass in an entrained-flow fast pyrolysis reactor. Analyses included elemental composition, carbon type distribution by {sup 13}C NMR, acid number, GC-MS, volatile organic acids by LC, and carbonyl compounds by DNPH derivatization and LC. Acid number titrations employed an improved titrant-electrode combination with faster response that allowed detection of multiple endpoints in many samples and for acid values attributable to carboxylic acids and to phenols to be distinguished. Results of these analyses showed that the highest oxygen content bio-oil fractions contained oxygen as carboxylic acids, carbonyls, aryl ethers, phenols, and alcohols. Carboxylic acids and carbonyl compounds detected in this sample were concentrated in the Light, Naphtha, and Jet fractions (<260 C boiling point). Carboxylic acid content of all of the high oxygen content fractions was likely too high for these materials to be considered as fuel blendstocks although potential for blending with crude oil or refinery intermediate streams may exist for the Diesel and Gasoil fractions. The 4.9 % oxygen sample contained almost exclusively phenolic compounds found to be present throughout the boiling range of this sample, but imparting measurable acidity primarily in the Light, Naphtha and Jet fractions. Additional study is required to understand what levels of the weakly acidic phenols could be tolerated in a refinery feedstock. The Diesel and Gasoil fractions from this upgraded oil had low acidity but still contained 3 to 4 wt% oxygen present as phenols that could not be specifically identified. These materials appear to have excellent potential as refinery feedstocks and some

  6. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates New Species of Cyanobacteria Forms Intracellular Carbonates Print Wednesday, 30 January 2013 00:00 A new species of ...

  7. Excess Oxygen Defects in Layered Cuprates

    DOE R&D Accomplishments [OSTI]

    Lightfoot, P.; Pei, S. Y.; Jorgensen, J. D.; Manthiram, A.; Tang, X. X.; Goodenough, J. B.

    1990-09-01

    Neutron powder diffraction has been used to study the oxygen defect chemistry of two non-superconducting layered cuprates, La{sub 1. 25}Dy{sub 0.75}Cu{sub 3.75}F{sub 0.5}, having a T{sup {asterisk}}- related structure, and La{sub 1.85}Sr{sub 1.15}Cu{sub 2}O{sub 6.25}, having a structure related to that of the newly discovered double-layer superconductor La{sub 2-x}Sr{sub x}CaCu{sub 2}O{sub 6}. The role played by oxygen defects in determining the superconducting properties of layered cuprates is discussed.

  8. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    Lawrence E. Bool; Jack C. Chen; David R. Thompson

    2000-10-01

    This quarterly technical progress report will summarize work accomplished for the Program through the second quarter July--September 2000 in the following task areas: Task 1-Oxygen Enhanced Combustion, Task 2-Oxygen Transport Membranes and Task 4-Program Management. The program is proceeding in accordance with the objectives for the first year. OTM tube characterization is well underway, the design and assembly of the high pressure permeation test facility is complete and the facility will be in full operation during the next quarter. Combustion testing has been initiated at both the University of Arizona and Praxair. Testing at the University of Arizona has experienced some delays; steps have been take to get the test work back on schedule. Completion of the first phase of the testing is expected in next quarter. Combustion modeling has been started at both REI and Praxair, preliminary results are expected in the next quarter.

  9. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, R.R.; Bond, J.A.

    1994-03-29

    A high-voltage electrical insulator for electrically insulating a thermoelectric module in a spacecraft from a niobium-1% zirconium alloy wall of a heat exchanger filled with liquid lithium while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator has a single crystal alumina layer (SxAl[sub 2]O[sub 3], sapphire) with a niobium foil layer bonded thereto on the surface of the alumina crystal facing the heat exchanger wall, and a molybdenum layer bonded to the niobium layer to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface. 3 figures.

  10. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, Roland R.; Bond, James A.

    1994-01-01

    A high-voltage electrical insulator (21) for electrically insulating a thermoelectric module (17) in a spacecraft from a niobium-1% zirconium alloy wall (11) of a heat exchanger (13) filled with liquid lithium (16) while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator (21) has a single crystal alumina layer (SxAl.sub.2 O.sub.3, sapphire) with a niobium foil layer (32) bonded thereto on the surface of the alumina crystal (26) facing the heat exchanger wall (11), and a molybdenum layer (31) bonded to the niobium layer (32) to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface.

  11. A miniature inexpensive, oxygen sensing element

    SciTech Connect (OSTI)

    Arenz, R.W.

    1991-10-07

    An exhaustive study was conducted to determine the feasibility of Nernst-type oxygen sensors based on ceramics containing Bi{sub 2}O{sub 3}. The basic sensor design consisted of a ceramic sensing module sealed into a metal tube. The module accommodated an internal heater and thermocouple. Thermal-expansion-matched metals, adhesives, and seals were researched and developed, consistent with sequential firings during sensor assembly. Significant effort was devoted to heater design/testing and to materials' compatibility with Pt electrodes. A systematic approach was taken to develop all sensor components which led to several design modifications. Prototype sensors were constructed and exhaustively tested. It is concluded that development of Nerst-type oxygen sensors based on Bi{sub 2}O{sub 3} will require much further effort and application of specialized technologies. However, during the course of this 3-year program much progress was reported in the literature on amperometric-type oxygen sensors, and a minor effort was devoted here to this type of sensor based on Bi{sub 2}O{sub 3}. These studies were made on Bi{sub 2}O{sub 3}-based ceramic samples in a multilayer-capacitor-type geometry and amperometric-type oxygen sensing was demonstrated at very low temperatures ({approximately} 160{degree}C). A central advantage here is that these types of sensors can be mass-produced very inexpensively ({approximately} 20--50 cents per unit). Research is needed, however, to develop an optimum diffusion-limiting barrier coating. In summary, the original goals of this program were not achieved due to unforeseen problems with Bi{sub 2}O{sub 3}-based Nernst sensors. However, a miniature amperometric sensor base on Bi{sub 2}O{sub 3} was demonstrated in this program, and it is now seen that this latter sensor is far superior to the originally proposed Nernst sensor. 6 refs., 24 figs.

  12. Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Platinum Monolayer Electrocatalysts for Oxygen Reduction Reaction Radoslav Adzic Co-workers: Jia Wang, Miomir Vukmirovic, Kotaro Sasaki, Stoyan Bliznakov, Yun Cai, Yu Zhang, Kurian Kuttiyiel, Kuanping Gong, YongMan Choi, Ping Liu, Hideo Naohara 1 Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973 1 Toyota Motor Corporation, Susono, Japan Webinar June 19, 2012 Outline - Introduction on fuel cells, electrocatalysis, existing developments and remaining obstacles to

  13. Oxygen stabilized zirconium vanadium intermetallic compound

    DOE Patents [OSTI]

    Mendelsohn, Marshall H.; Gruen, Dieter M.

    1982-01-01

    An oxygen stabilized intermetallic compound having the formula Zr.sub.x OV.sub.y where x=0.7 to 2.0 and y=0.18 to 0.33. The compound is capable of reversibly sorbing hydrogen at temperatures from -196.degree. C. to 450.degree. C. at pressures down to 10.sup.-6 Torr. The compound is also capable of selectively sorbing hydrogen from gaseous mixtures in the presence of CO and CO.sub.2.

  14. Hydrogen (H2) Production by Oxygenic Phototrophs

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Production by Oxygenic Phototrophs Eric L. Hegg Michigan State University Great Lakes Bioenergy Research Center Bioresour. Technol. 2011, 102, 8589-8604 Major Challenges to H 2 Photoproduction Biological Challenges * Poor efficiency of H 2 production * Poor heterologous expression of H 2 -forming enzymes * Low quantum yields * Competition for reducing equivalents; poor electron coupling * Sensitivity of H 2 -forming enzymes to O 2 M. Ghirardi, Abstract #1751, Honolulu PRiME 2012 Technical

  15. Oxygen Catalysis: The Other Half of the Equation

    SciTech Connect (OSTI)

    Turner, J.

    2008-10-01

    Artificial photosynthesis--splitting water with light--is an attractive way to make hydrogen, but what happens to the oxygen? A catalyst that aids in the efficient production of gaseous oxygen improves the viability of this approach.

  16. Impact of interstitial oxygen on the electronic and magnetic...

    Office of Scientific and Technical Information (OSTI)

    interstitial oxygen on the electronic and magnetic structure in superconducting Fe 1 + y Te O x thin films Citation Details In-Document Search Title: Impact of interstitial oxygen...

  17. DME-to-oxygenates process studies

    SciTech Connect (OSTI)

    Tartamella, T.L.; Sardesai, A.; Lee, S.; Kulik, C.J.

    1994-12-31

    The feasibility of the production of hydrocarbons from dimethyl ether (DNM) has been illustrated in a fixed bed micro-reactor as well as a bench scale fluidized bed reactor by the University of Akron/EPRI DME-to-Hydrocarbon (DTG) Process. The DTG process has distinct advantages over its methanol based counterpart. Specifically, the DTG process excels in the area of higher productivity, higher per-pass conversion, and lower heat duties than the MTG process. Also of special importance is the production of oxygenates -- including MTBE, ETBE, and TAME. DME may be reacted with isobutylene to produce a mixture of MTBE and ETBE. The properties of ETBE excel over MTBE in the areas of lower RVP and higher RON. According to industrial reports, MTBE is the fastest growing chemical (1992 US capacity 135,350 BPD, with expected growth of 34%/year to 1997). Also, recent renewed interest as an octane-enhancer and as a source of oxygen has spurred a growing interest in nonrefinery synthesis routes to ETBE. TAME, with its lower RVP and higher RON has proven useful as a gasoline blending agent and octane enhancer and may also be produced directly from DME. DME, therefore, serves as a valuable feedstock in the conversion of may oxygenates with wide-scale industrial importance. It should be also noted that the interest in the utilization of DME as process feedstock is based on the favorable process economics of EPRI/UA`s liquid phase DME process.

  18. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    SciTech Connect (OSTI)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2002-08-01

    This quarterly technical progress report will summarize work accomplished for the Program through the ninth quarter April-June 2002 in the following task areas: Task 1--Oxygen Enhanced Combustion, Task 2--Oxygen Transport Membranes, Task 3--Economic Evaluation and Task 4--Program Management. The program is proceeding in accordance with the objectives for the third year. Full-scale testing using the Industrial Boiler Simulation Facility (ISBF) at Alstom Power was completed. The pilot scale experiments to evaluate the effect of air preheat and transport air stoichiometric ratio (SR) on NOx emissions were conducted at the University of Utah. Combustion modeling activities continued with full-scale combustion test furnace simulations. An OTM element was tested in Praxair's single tube high-pressure test facility and two thermal cycles were completed. PSO1d elements of new dimension were tested resulting in a lower flux than previous PSO1d elements of different dimensions, however, no element deformation was observed. Economic evaluation has confirmed the advantage of oxygen-enhanced combustion. Two potential host beta sites have been identified and proposals submitted.

  19. Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process Regenerable Mixed Copper-Iron-Inert Support Oxygen Carriers National Energy Technology Laboratory Contact NETL About This Technology Publications: PDF Document Publication 13159553.pdf (405 KB) Technology Marketing Summary This patent-pending technology, "Regenerable Mixed Copper-Iron-Inert Support Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process," provides a metal-oxide oxygen

  20. Oxygen-Enriched Combustion for Military Diesel Engine Generators |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Oxygen-Enriched Combustion for Military Diesel Engine Generators Oxygen-Enriched Combustion for Military Diesel Engine Generators Substantial increases in brake power and considerably lower peak pressure can result from oxygen-enriched diesel combustion deer09_yelvington.pdf (196.85 KB) More Documents & Publications Development Methodology for Power-Dense Military Diesel Engine Oxygen-Enriched Combustion Emission Control Strategy for Downsized Light-Duty Diese

  1. Dilute Oxygen Combustion Phase IV Final Report

    SciTech Connect (OSTI)

    Riley, M.F.

    2003-04-30

    Novel furnace designs based on Dilute Oxygen Combustion (DOC) technology were developed under subcontract by Techint Technologies, Coraopolis, PA, to fully exploit the energy and environmental capabilities of DOC technology and to provide a competitive offering for new furnace construction opportunities. Capital cost, fuel, oxygen and utility costs, NOx emissions, oxide scaling performance, and maintenance requirements were compared for five DOC-based designs and three conventional air5-fired designs using a 10-year net present value calculation. A furnace direct completely with DOC burners offers low capital cost, low fuel rate, and minimal NOx emissions. However, these benefits do not offset the cost of oxygen and a full DOC-fired furnace is projected to cost $1.30 per ton more to operate than a conventional air-fired furnace. The incremental cost of the improved NOx performance is roughly $6/lb NOx, compared with an estimated $3/lb. NOx for equ8pping a conventional furnace with selective catalytic reduction (SCCR) technology. A furnace fired with DOC burners in the heating zone and ambient temperature (cold) air-fired burners in the soak zone offers low capital cost with less oxygen consumption. However, the improvement in fuel rate is not as great as the full DOC-fired design, and the DOC-cold soak design is also projected to cost $1.30 per ton more to operate than a conventional air-fired furnace. The NOx improvement with the DOC-cold soak design is also not as great as the full DOC fired design, and the incremental cost of the improved NOx performance is nearly $9/lb NOx. These results indicate that a DOC-based furnace design will not be generally competitive with conventional technology for new furnace construction under current market conditions. Fuel prices of $7/MMBtu or oxygen prices of $23/ton are needed to make the DOC furnace economics favorable. Niche applications may exist, particularly where access to capital is limited or floor space limitations

  2. BLM Sensitive Species | Open Energy Information

    Open Energy Info (EERE)

    BLM Sensitive Species Jump to: navigation, search Retrieved from "http:en.openei.orgwindex.php?titleBLMSensitiveSpecies&oldid612378...

  3. Chemical diffusion of oxygen in tin dioxide: Effects of dopants and oxygen partial pressure

    SciTech Connect (OSTI)

    Kamp, B.; Merkle, R. . E-mail: s.weiglein@fkf.mpg.de; Lauck, R.; Maier, J.

    2005-10-15

    Tin dioxide SnO{sub 2-{delta}} is a pronounced n-type electron conductor due to its oxygen deficiency. This study investigates the rate of chemical diffusion of oxygen in SnO{sub 2-{delta}} single crystals, which is a crucial step in the overall stoichiometry change of the material. The chemical diffusion coefficient D{sup {delta}} was determined from conductivity- and EPR-relaxation methods. The temperature dependence was found to be D{sup {delta}}=exp(-4+/-2)cm{sup 2}s{sup -1}exp(-(1.1+/-0.3)eV/kT). The dependence on crystal orientation, dopant content and oxygen partial pressure was below experimental error. The latter observation leads to the conclusion that the chemical diffusion coefficient is close to the diffusion coefficient of oxygen vacancies. Along with the relaxation process resulting from the chemical diffusion of oxygen, additional processes were observed. One of these was attributed to complications in the defect chemistry of the material. The relevance of the results for the kinetics of drift processes of Taguchi sensors is discussed.

  4. Mechanism of singlet oxygen deactivation in an electric discharge oxygen – iodine laser

    SciTech Connect (OSTI)

    Azyazov, V N; Mikheyev, P A; Torbin, A P; Pershin, A A; Heaven, M C

    2014-12-31

    We have determined the influence of the reaction of molecular singlet oxygen with a vibrationally excited ozone molecule O{sub 2}(a {sup 1}Δ) + O{sub 3}(ν) → 2O{sub 2} + O on the removal rate of O{sub 2}(a {sup 1}Δ) in an electric-discharge-driven oxygen – iodine laser. This reaction has been shown to be a major channel of O{sub 2}(a {sup 1}Δ) loss at the output of an electric-discharge singlet oxygen generator. In addition, it can also contribute significantly to the loss of O{sub 2}(a {sup 1}Δ) in the discharge region of the generator. (lasers)

  5. Investigation of the electrocatalytic oxygen reduction and evolution reactions in lithium–oxygen batteries

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zheng, Dong; Zhang, Xuran; Qu, Deyu; Yang, Xiao -Qing; Lee, Hung -Sui; Qu, Deyang

    2015-04-21

    Oxygen reduction and oxygen evolution reactions were examined on graphite electrodes with different crystal orientations. The kinetics for the redox couple O2/O2•- are very fast, therefore no catalyst seems necessary to assist the charge transfer process. Apparently, the main source of the overpotential for the O2 reduction reaction is from mass diffusion. Li2O2 becomes soluble in non-aqueous electrolytes in the presence of the tetraethylammonium tetrafluoroborate additive. The soluble B-O22- ions can be oxidized electro-catalytically. The edge orientation of graphite demonstrates superior catalytic activity for the oxidation over basal orientation. The findings reveal an opportunity for recharging Li-air batteries efficiently andmore » a new strategy of developing the catalyst for oxygen evolution reaction.« less

  6. Investigation of the electrocatalytic oxygen reduction and evolution reactions in lithiumoxygen batteries

    SciTech Connect (OSTI)

    Zheng, Dong; Zhang, Xuran; Qu, Deyu; Yang, Xiao -Qing; Lee, Hung -Sui; Qu, Deyang

    2015-04-21

    Oxygen reduction and oxygen evolution reactions were examined on graphite electrodes with different crystal orientations. The kinetics for the redox couple O2/O2- are very fast, therefore no catalyst seems necessary to assist the charge transfer process. Apparently, the main source of the overpotential for the O2 reduction reaction is from mass diffusion. Li2O2 becomes soluble in non-aqueous electrolytes in the presence of the tetraethylammonium tetrafluoroborate additive. The soluble B-O22- ions can be oxidized electro-catalytically. The edge orientation of graphite demonstrates superior catalytic activity for the oxidation over basal orientation. The findings reveal an opportunity for recharging Li-air batteries efficiently and a new strategy of developing the catalyst for oxygen evolution reaction.

  7. The Mechanisms of Oxygen Reduction and Evolution Reactions in Nonaqueous Lithium-Oxygen Batteries

    SciTech Connect (OSTI)

    Cao, Ruiguo; Walter, Eric D.; Xu, Wu; Nasybulin, Eduard N.; Bhattacharya, Priyanka; Bowden, Mark E.; Engelhard, Mark H.; Zhang, Jiguang

    2014-09-01

    The oxygen reduction/evolution reaction (ORR/OER) mechanisms in nonaqueous Li-O2 batteries have been investigated by using electron paramagnetic resonance spectroscopy in this work. We identified the superoxide radical anion (O2•-) as an intermediate in the ORR process using 5,5-dimethyl-pyrroline N-oxide as a spin trap, while no O2•- in OER was detected during the charge process. These findings provide insightful understanding on the fundamental oxygen reaction mechanisms in rechargeable nonaqueous Li-O2 batteries.

  8. Cathode architectures for alkali metal / oxygen batteries

    SciTech Connect (OSTI)

    Visco, Steven J; Nimon, Vitaliy; De Jonghe, Lutgard C; Volfkovich, Yury; Bograchev, Daniil

    2015-01-13

    Electrochemical energy storage devices, such as alkali metal-oxygen battery cells (e.g., non-aqueous lithium-air cells), have a cathode architecture with a porous structure and pore composition that is tailored to improve cell performance, especially as it pertains to one or more of the discharge/charge rate, cycle life, and delivered ampere-hour capacity. A porous cathode architecture having a pore volume that is derived from pores of varying radii wherein the pore size distribution is tailored as a function of the architecture thickness is one way to achieve one or more of the aforementioned cell performance improvements.

  9. Oxygen stabilized zirconium-vanadium-iron alloy

    DOE Patents [OSTI]

    Mendelsohn, Marshall H.; Gruen, Dieter M.

    1982-01-01

    An oxygen stabilized intermetallic compound having the formula (Zr.sub.1-x Ti.sub.x).sub.2-u (V.sub.1-y Fe.sub.y)O.sub.z where x=0.0 to 0.9, y=0.01 to 0.9, z=0.25 to 0.5 and u=0 to 1. The compound is capable of reversibly sorbing hydrogen at temperatures from -196.degree. C. to 200.degree. C. at pressures down to 10.sup.-6 torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices.

  10. Comparison of killing of gram-negative and gram-positive bacteria by pure singlet oxygen. [Salmonella typhimurium; Escherichia coli; Sarcina lutea; Staphylococcus aureus; Streptococcus lactis; Streptococcus faecalis

    SciTech Connect (OSTI)

    Dahl, T.A.; Midden, W.R. ); Hartman, P.E. )

    1989-04-01

    Gram-negative and gram-positive bacteria were found to display different sensitivities to pure singlet oxygen generated outside of cells. Killing curves for Salmonella typhimurium and Escherichia coli strains were indicative of multihit killing, whereas curves for Sarcina lutea, Staphylococcus aureus, Streptococcus lactis, and Streptococcus faecalis exhibited single-hit kinetics. The S. typhimurium deep rough strain TA1975, which lacks nearly all of the cell wall lipopolysaccharide coat and manifests concomitant enhancement of penetration by some exogenous substances, responded to singlet oxygen with initially faster inactivation than did the S. typhimurium wild-type strain, although the maximum rates of killing appeared to be quite similar. The structure of the cell wall thus plays an important role in susceptibility to singlet oxygen. The outer membrane-lipopolysaccharide portion of the gram-negative cell wall initially protects the bacteria from extracellular singlet oxygen, although it may also serve as a source for secondary reaction products which accentuate the rates of cell killing. S. typhimurium and E. coli strains lacking the cellular antioxidant, glutathione, showed no difference from strains containing glutathione in response to the toxic effects of singlet oxygen. Strains of Sarcina lutea and Staphylococcus aureus that contained carotenoids, however, were far more resistant to singlet oxygen lethality than were both carotenoidless mutants of the same species and other gram-positive species lacking high levels of protective carotenoids.

  11. Electrochemical oxygen pumps. Final CRADA report.

    SciTech Connect (OSTI)

    Carter, J. D. Noble, J.

    2009-10-01

    All tasks of the Work Plan of ISTC Project 2277p have been completed, thus: (1) techniques of chemical synthesis were developed for more than ten recipes of electrolyte based on cerium oxide doped with 20 mole% of gadolinium (CeGd)O{sub 2}, doped by more than 10 oxide systems including 6 recipes in addition to the Work Plan; (2) electric conductivity and mechanical strength of CeGd specimens with additions of oxide systems were performed, two candidate materials for the electrolyte of electrochemical oxygen pump (pure CeGd and CeGd doped by 0.2 wt% of a transition metal) were chosen; (3) extended studies of mechanical strength of candidate material specimens were performed at room temperature and at 400, 600, 800 C; (4) fixtures for determination of mechanical strength of tubes by external pressure above 40 atmospheres at temperature up to 700 C were developed and fabricated; and (5) technology of slip casting of tubes from pure (Ce,Gd)O{sub 2} and of (Ce,Gd)O{sub 2} doped by 0.2 wt% of a transition metal, withstanding external pressure of minimum 40 atmospheres at temperature up to 700 C was developed, a batch of tubes was sent for testing to Argonne National Laboratory; (6) technology of making nanopowder from pure (Ce,Gd)O{sub 2} was developed based on chemical synthesis and laser ablation techniques, a batch of nanopowder with the weight 1 kg was sent for testing to Argonne National Laboratory; (7) a business plan for establishing a company for making powders of materials for electrochemical oxygen pump was developed; and (8) major results obtained within the Project were reported at international conferences and published in the Russian journal Electrochemistry. In accordance with the Work Plan a business trip of the following project participants was scheduled for April 22-29, 2006, to Tonawanda, NY, USA: Manager Victor Borisov; Leader of technology development Gennady Studenikin; Leader of business planning Elena Zadorozhnaya; Leader of production Vasily

  12. Oxygen Handling and Cooling Options in High Temperature Electrolysis Plants

    SciTech Connect (OSTI)

    Manohar S. Sohal; J. Stephen Herring

    2008-07-01

    Idaho National Laboratory is working on a project to generate hydrogen by high temperature electrolysis (HTE). In such an HTE system, safety precautions need to be taken to handle high temperature oxygen at ~830°C. This report is aimed at addressing oxygen handling in a HTE plant.. Though oxygen itself is not flammable, most engineering material, including many gases and liquids, will burn in the presence of oxygen under some favorable physicochemical conditions. At present, an absolute set of rules does not exist that can cover all aspects of oxygen system design, material selection, and operating practices to avoid subtle hazards related to oxygen. Because most materials, including metals, will burn in an oxygen-enriched environment, hazards are always present when using oxygen. Most materials will ignite in an oxygen-enriched environment at a temperature lower than that in air, and once ignited, combustion rates are greater in the oxygen-enriched environment. Even many metals, if ignited, burn violently in an oxygen-enriched environment. However, these hazards do not preclude the operations and systems involving oxygen. Oxygen can be safely handled and used if all the materials in a system are not flammable in the end-use environment or if ignition sources are identified and controlled. In fact, the incidence of oxygen system fires is reported to be low with a probability of about one in a million. This report is a practical guideline and tutorial for the safe operation and handling of gaseous oxygen in high temperature electrolysis system. The intent is to provide safe, practical guidance that permits the accomplishment of experimental operations at INL, while being restrictive enough to prevent personnel endangerment and to provide reasonable facility protection. Adequate guidelines are provided to govern various aspects of oxygen handling associated with high temperature electrolysis system to generate hydrogen. The intent here is to present acceptable

  13. Nitrogen-doped carbon-supported cobalt-iron oxygen reduction catalyst

    DOE Patents [OSTI]

    Zelenay, Piotr; Wu, Gang

    2014-04-29

    A Fe--Co hybrid catalyst for oxygen reaction reduction was prepared by a two part process. The first part involves reacting an ethyleneamine with a cobalt-containing precursor to form a cobalt-containing complex, combining the cobalt-containing complex with an electroconductive carbon supporting material, heating the cobalt-containing complex and carbon supporting material under conditions suitable to convert the cobalt-containing complex and carbon supporting material into a cobalt-containing catalyst support. The second part of the process involves polymerizing an aniline in the presence of said cobalt-containing catalyst support and an iron-containing compound under conditions suitable to form a supported, cobalt-containing, iron-bound polyaniline species, and subjecting said supported, cobalt-containing, iron bound polyaniline species to conditions suitable for producing a Fe--Co hybrid catalyst.

  14. Preliminary Study of Oxygen-Enhanced Longitudinal Relaxation in MRI: A Potential Novel Biomarker of Oxygenation Changes in Solid Tumors

    SciTech Connect (OSTI)

    O'Connor, James P.B.; Naish, Josephine H.; Parker, Geoff J.M.; Waterton, John C.; Watson, Yvonne; Jayson, Gordon C.; Buonaccorsi, Giovanni A.; Cheung, Sue; Buckley, David L.; McGrath, Deirdre M.; West, Catharine M.L.; Davidson, Susan E.; Roberts, Caleb; Mills, Samantha J.; Mitchell, Claire L.; Hope, Lynn; Ton, N. Chan; Jackson, Alan

    2009-11-15

    Purpose: There is considerable interest in developing non-invasive methods of mapping tumor hypoxia. Changes in tissue oxygen concentration produce proportional changes in the magnetic resonance imaging (MRI) longitudinal relaxation rate (R{sub 1}). This technique has been used previously to evaluate oxygen delivery to healthy tissues and is distinct from blood oxygenation level-dependent (BOLD) imaging. Here we report application of this method to detect alteration in tumor oxygenation status. Methods and materials: Ten patients with advanced cancer of the abdomen and pelvis underwent serial measurement of tumor R{sub 1} while breathing medical air (21% oxygen) followed by 100% oxygen (oxygen-enhanced MRI). Gadolinium-based dynamic contrast-enhanced MRI was then performed to compare the spatial distribution of perfusion with that of oxygen-induced DELTAR{sub 1}. Results: DELTAR{sub 1} showed significant increases of 0.021 to 0.058 s{sup -1} in eight patients with either locally recurrent tumor from cervical and hepatocellular carcinomas or metastases from ovarian and colorectal carcinomas. In general, there was congruency between perfusion and oxygen concentration. However, regional mismatch was observed in some tumor cores. Here, moderate gadolinium uptake (consistent with moderate perfusion) was associated with low area under the DELTAR{sub 1} curve (consistent with minimal increase in oxygen concentration). Conclusions: These results provide evidence that oxygen-enhanced longitudinal relaxation can monitor changes in tumor oxygen concentration. The technique shows promise in identifying hypoxic regions within tumors and may enable spatial mapping of change in tumor oxygen concentration.

  15. METHOD OF COMBINING HYDROGEN AND OXYGEN

    DOE Patents [OSTI]

    McBride, J.P.

    1962-02-27

    A method is given for the catalytic recombination of radiolytic hydrogen and/or deulerium and oxygen resulting from the subjection or an aqueous thorium oxide or thorium oxide-uranium oxide slurry to ionizing radiation. An improved catalyst is prepared by providing paliadium nitrate in an aqueous thorium oxide sol at a concentration of at least 0.05 grams per gram of thorium oxide and contacting the sol with gaseous hydrogen to form flocculated solids. The solids are then recovered and added to the slurry to provide a palladium concentration of 100 to 1000 parts per million. Recombination is effected by the calalyst at a rate sufficient to support high nuclear reactor power densities. (AEC)

  16. SUPPORTED DENSE CERAMIC MEMBRANES FOR OXYGEN SEPARATION

    SciTech Connect (OSTI)

    Timothy L. Ward

    2002-07-01

    Mixed-conducting ceramics have the ability to conduct oxygen with perfect selectivity at elevated temperatures, making them extremely attractive as membrane materials for oxygen separation and membrane reactor applications. While the conductivity of these materials can be quite high at elevated temperatures (typically 800-1000 C), much higher oxygen fluxes, or, alternatively, equivalent fluxes at lower temperatures, could be provided by supported thin or thick film membrane layers. Based on that motivation, the objective of this project was to explore the use of ultrafine aerosol-derived powder of a mixed-conducting ceramic material for fabrication of supported thick-film dense membranes. The project focused on the mixed-conducting ceramic composition SrCo{sub 0.5}FeO{sub x} (SCFO) because of the desirable permeability and stability of that material, as reported in the literature. Appropriate conditions to produce the submicron SrCo{sub 0.5}FeO{sub x} powder using aerosol pyrolysis were determined. Porous supports of the same composition were produced by partial sintering of a commercially obtained powder that possessed significantly larger particle size than the aerosol-derived powder. The effects of sintering conditions (temperature, atmosphere) on the porosity and microstructure of the porous discs were studied, and a standard support fabrication procedure was adopted. Subsequently, a variety of paste and slurry formulations were explored utilizing the aerosol-derived SCFO powder. These formulations were applied to the porous SCFO support by a doctor blade or spin coating procedure. Sintering of the supported membrane layer was then conducted, and additional layers were deposited and sintered in some cases. The primary characterization methods were X-ray diffraction and scanning electron microscopy, and room-temperature nitrogen permeation was used to assess defect status of the membranes.We found that non-aqueous paste/slurry formulations incorporating

  17. Dilute Oxygen Combustion - Phase 3 Report

    SciTech Connect (OSTI)

    Riley, Michael F.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good, and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel's standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion on furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  18. Dilute Oxygen Combustion Phase 3 Final Report

    SciTech Connect (OSTI)

    Riley, M.F.; Ryan, H.M.

    2000-05-31

    Dilute Oxygen Combustion (DOC) burners have been successfully installed and operated in the reheat furnace at Auburn Steel Co., Inc., Auburn, NY, under Phase 3 of the Dilute Oxygen Combustion project. Two new preheat zones were created employing a total of eight 6.5 MMBtu/hr capacity burners. The preheat zones provide a 30 percent increase in maximum furnace production rate, from 75 tph to 100 tph. The fuel rate is essentially unchanged, with the fuel savings expected from oxy-fuel combustion being offset by higher flue gas temperatures. When allowance is made for the high nitrogen level and high gas phase temperature in the furnace, measured NOx emissions are in line with laboratory data on DOC burners developed in Phase 1 of the project. Burner performance has been good and there have been no operating or maintenance problems. The DOC system continues to be used as part of Auburn Steel?s standard reheat furnace practice. High gas phase temperature is a result of the high firing density needed to achieve high production rates, and little opportunity exists for improvement in that area. However, fuel and NOx performance can be improved by further conversion of furnace zones to DOC burners, which will lower furnace nitrogen levels. Major obstacles are cost and concern about increased formation of oxide scale on the steel. Oxide scale formation may be enhanced by exposure of the steel to higher concentrations of oxidizing gas components (primarily products of combustion) in the higher temperature zones of the furnace. Phase 4 of the DOC project will examine the rate of oxide scale formation in these higher temperature zones and develop countermeasures that will allow DOC burners to be used successfully in these furnace zones.

  19. Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technique | Department of Energy Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique Presentation slides from the Fuel Cell Technologies Office webinar, "Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique," held March 12, 2013. Presenters were Shyam S. Kocha, National Renewable Energy Laboratory; Yannick Garsany, Naval Research

  20. Oxygen detected in atmosphere of Saturn's moon Dione

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Oxygen detected in atmosphere of Saturn's moon Dione Oxygen detected in atmosphere of Saturn's moon Dione Scientists and an international research team have announced discovery of molecular oxygen ions in the upper-most atmosphere of Dione. March 3, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics

  1. Direct Observation of Localized Radial Oxygen Migration in Functioning

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tantalum Oxide Memristors Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors Print Monday, 11 April 2016 14:29 As information bits of 0s and 1s are stored in crosspoint tantalum oxide memristors, or resistive random access memory (RRAM) cells, nanoscale-resolution in operando x-ray transmission spectromicroscopy is used to directly observe oxygen

  2. Elusive Oxygen Isotope Captured with Groundbreaking Sensitivity | The Ames

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory Elusive Oxygen Isotope Captured with Groundbreaking Sensitivity Oxygen is one of the most ubiquitous elements in chemistry and materials science, yet one of the most elusive elements for spectroscopic investigation by solid-state Nuclear Magnetic Resonance (SSNMR). Used to determine the structure of materials and chemicals on the atomic scale, SSNMR requires nuclei that have magnetic moments. Yet, less than four of every 10,000 oxygen nuclei are 17O, the only NMR-active isotope of

  3. Hybrid System for Separating Oxygen from Air - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogen and Fuel Cell Hydrogen and Fuel Cell Energy Storage Energy Storage Find More Like This Return to Search Hybrid System for Separating Oxygen from Air Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (765 KB) Technology Marketing Summary Sandia has developed a portable, oxygen generation system capable of delivering oxygen gas at purities greater than 98 percent and flow rates significantly greater than commercially

  4. Sensor Rapidly Measures the Concentration of Oxygen in Fluids - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Vehicles and Fuels Vehicles and Fuels Find More Like This Return to Search Sensor Rapidly Measures the Concentration of Oxygen in Fluids Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryTo provide rapid measurement of oxygen concentrations in fluids, ORNL researchers developed a sensor that measures oxygen in temperatures from 0 degrees Celsius up to the 200 degrees Celsius commonly found in intake manifolds. The sensor can be

  5. Advantages of Oxygenates Fuels over Gasoline in Direct Injection...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Advantages of Oxygenates Fuels over Gasoline in Direct Injection Spark Ignition Engines Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) ...

  6. Probing oxygen vacancy concentration and homogeneity in solid...

    Office of Scientific and Technical Information (OSTI)

    Here, we develop an approach for direct mapping of oxygen vacancy concentrations based on local lattice parameter measurements by scanning transmission electron microscopy. The ...

  7. Strain control of oxygen vacancies in epitaxial strontium cobaltite...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Strain control of oxygen vacancies in epitaxial strontium cobaltite films ... This content will become publicly available on January 25, 2017 Title: Strain control of ...

  8. Oxygen detected in atmosphere of Saturn's moon Dione

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is the possibility that on a moon with subsurface water, such as Jupiter's moon Europa, molecular oxygen could combine with carbon in subsurface lakes to form the building...

  9. Selective reduction of NOx in oxygen rich environments with plasma...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    environments with plasma-assisted catalysis: Catalyst development and mechanistic studies Selective reduction of NOx in oxygen rich environments with plasma-assisted catalysis: ...

  10. Catalytic reduction system for oxygen-rich exhaust

    DOE Patents [OSTI]

    Vogtlin, George E.; Merritt, Bernard T.; Hsiao, Mark C.; Wallman, P. Henrik; Penetrante, Bernardino M.

    1999-01-01

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.

  11. Vehicle Technologies Office Merit Review 2014: Intake Air Oxygen...

    Energy Savers [EERE]

    Review 2015: Intake Air Oxygen Sensor Vehicle Technologies Office Merit Review 2014: Advanced Combustion Concepts - Enabling Systems and Solutions (ACCESS) for High Efficiency...

  12. Vehicle Technologies Office Merit Review 2015: Intake Air Oxygen...

    Energy Savers [EERE]

    Office Merit Review 2014: Intake Air Oxygen Sensor Bosch Powertrain Technologies Advanced Combustion Concepts - Enabling Systems and Solutions (ACCESS) for High Efficiency...

  13. Ultrafast kinetics subsequent to shock compression in an oxygen...

    Office of Scientific and Technical Information (OSTI)

    to shock compression in an oxygen-balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock ...

  14. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an ...

  15. Catalytic reduction system for oxygen-rich exhaust

    DOE Patents [OSTI]

    Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

    1999-04-13

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

  16. Electrocatalyst for Oxygen Reduction with Reduced Platinum Oxidation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates The invention relates to platinum-metal oxide composite particles and their use as...

  17. Strain control of oxygen vacancies in epitaxial strontium cobaltite films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jeen, Hyoung Jeen; Choi, Woo Seok; Reboredo, Fernando A.; Freeland, John W.; Eres, Gyula; Lee, Ho Nyung; Petrie, Jonathan R.; Mitra, Chandrima; Meyer, Tricia L.

    2016-01-25

    In this study, the ability to manipulate oxygen anion defects rather than metal cations in complex oxides can facilitate creating new functionalities critical for emerging energy and device technologies. However, the difficulty in activating oxygen at reduced temperatures hinders the deliberate control of important defects, oxygen vacancies. Here, strontium cobaltite (SrCoOx) is used to demonstrate that epitaxial strain is a powerful tool for manipulating the oxygen vacancy concentration even under highly oxidizing environments and at annealing temperatures as low as 300 °C. By applying a small biaxial tensile strain (2%), the oxygen activation energy barrier decreases by ≈30%, resulting inmore » a tunable oxygen deficient steady-state under conditions that would normally fully oxidize unstrained cobaltite. These strain-induced changes in oxygen stoichiometry drive the cobaltite from a ferromagnetic metal towards an antiferromagnetic insulator. The ability to decouple the oxygen vacancy concentration from its typical dependence on the operational environment is useful for effectively designing oxides materials with a specific oxygen stoichiometry.« less

  18. Oxidation State and Interfacial Effects on Oxygen Vacancies in...

    Office of Scientific and Technical Information (OSTI)

    Oxygen Vacancies in Tantalum Pentoxide. Abstract not provided. Authors: Bondi, Robert James ; Marinella, Matthew Publication Date: 2014-10-01 OSTI Identifier: 1184499 Report...

  19. Role of strain and conductivity in oxygen electrocatalysis on...

    Office of Scientific and Technical Information (OSTI)

    The slow kinetics of the oxygen reduction and evolution reactions (ORR, OER) hinder energy conversion and storage in alkaline fuel cells and electrolyzers employing abundant ...

  20. The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl...

    Office of Scientific and Technical Information (OSTI)

    Title: The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl Impurity Defects on Titanium Dioxide (110) Surface Introducing a charge into a solid such as a metal oxide ...

  1. Oxygen-Enriched Combustion for Military Diesel Engine Generators...

    Broader source: Energy.gov (indexed) [DOE]

    (196.85 KB) More Documents & Publications Development Methodology for Power-Dense Military Diesel Engine Oxygen-Enriched Combustion Emission Control Strategy for Downsized ...

  2. Table 33. Oxygenated Motor Gasoline Prices by Grade, Sales Type...

    U.S. Energy Information Administration (EIA) Indexed Site

    - - - - - - - - - - - - See footnotes at end of table. 33. Oxygenated Motor Gasoline Prices by Grade, Sales Type, PAD District, and State 116 Energy Information...

  3. Table 33. Oxygenated Motor Gasoline Prices by Grade, Sales Type...

    U.S. Energy Information Administration (EIA) Indexed Site

    Information Administration Petroleum Marketing Annual 1995 Table 33. Oxygenated Motor Gasoline Prices by Grade, Sales Type, PAD District, and State (Cents per Gallon...

  4. Tritons and tritides as the solute and diffusing species in ceramic tritium breeders

    SciTech Connect (OSTI)

    Fischer, A.K.; Johnson, C.E.

    1987-01-01

    Intragranular diffusion of tritium is an inherent participant in the process of releasing tritium from lithium-containing ceramics that are used to breed tritium in a fusion reactor. The nature of this transport is reviewed in terms of the understanding established for the mechanism of hydrogen migration in other oxides, namely, that the diffusing species is the proton and that it moves from oxide ion to oxide ion, thereby giving rise to apparent hydroxide migration. Analogously, the triton, transiently bonded to successive oxides and forming successive tritoxides, is taken to be the dominant migrating species in ceramic breeders. In addition, tritide becomes a significant participant at low oxygen activity. The relationship of tritons and tritides as the migrating species to the observed release of both reduced and oxidized forms can be understood in terms of the thermodynamic conditions that prevail. Mechanisms exist that can be proposed to rationalize the participation of these species.

  5. Oxygen diffusion of anodic surface oxide film on titanium studied by Auger electron spectroscopy. [Oxygen diffusivity

    SciTech Connect (OSTI)

    Wang, P.S.; Wittberg, T.N.; Keil, R.G.

    1982-01-01

    TiO/sub 2/ films of about 1000 A were grown onto titanium foils anodically under galvanostatic conditions at 20 mA/cm/sup 2/ in saturated aqueous solutions of ammonium tetraborate. The samples were then aged at 450, 500, and 550/sup 0/C, and oxygen diffusion was observed by Auger electron spectroscopy (AES) profilings. The oxygen diffusivities were calculated by Fick's Second Law, using the Boltzmann-Matano solution, to be 9.4 x 10/sup -17/, 2.6 x 10/sup -16/, and 1.2 x 10/sup -15/ cm/sup 2//sec at 450, 500, and 550/sup 0/C, respectively. The diffusivities obtained by this method were also compared with those obtained using an exact solution to Fick's Second Law. The activation energy was calculated to be 30 kcal/mole.

  6. Invasive, Nonnative Species | Open Energy Information

    Open Energy Info (EERE)

    Species Jump to: navigation, search Retrieved from "http:en.openei.orgwindex.php?titleInvasive,NonnativeSpecies&oldid647789" Feedback Contact needs updating...

  7. Special Status Species | Open Energy Information

    Open Energy Info (EERE)

    Status Species Jump to: navigation, search Retrieved from "http:en.openei.orgwindex.php?titleSpecialStatusSpecies&oldid647804" Feedback Contact needs updating Image...

  8. Threatened and Endangered Species | Open Energy Information

    Open Energy Info (EERE)

    Threatened and Endangered Species Jump to: navigation, search Retrieved from "http:en.openei.orgwindex.php?titleThreatenedandEndangeredSpecies&oldid612178...

  9. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the...

  10. Endangered Species Act and Section 7 Regulations

    Broader source: Energy.gov [DOE]

    The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend.

  11. Effects of oxygen and catalyst on tetraphenylborate decomposition rate

    SciTech Connect (OSTI)

    Walker, D.D.

    1999-12-15

    Previous studies indicate that palladium catalyzes rapid decomposition of alkaline tetraphenylborate slurries. Oxygen inhibits the reaction at low temperature (25 C), presumably by preventing activation of the catalyst. The present study investigated oxygen's inhibiting effectiveness at higher temperature (45 C) and catalyst concentrations.

  12. Palladium-cobalt particles as oxygen-reduction electrocatalysts

    DOE Patents [OSTI]

    Adzic, Radoslav; Huang, Tao

    2009-12-15

    The present invention relates to palladium-cobalt particles useful as oxygen-reducing electrocatalysts. The invention also relates to oxygen-reducing cathodes and fuel cells containing these palladium-cobalt particles. The invention additionally relates to methods for the production of electrical energy by using the palladium-cobalt particles of the invention.

  13. Low NOx combustion using cogenerated oxygen and nitrogen streams

    DOE Patents [OSTI]

    Kobayashi, Hisashi; Bool, Lawrence E.; Snyder, William J.

    2009-02-03

    Combustion of hydrocarbon fuel is achieved with less formation of NOx by feeding the fuel into a slightly oxygen-enriched atmosphere, and separating air into oxygen-rich and nitrogen-rich streams which are fed separately into the combustion device.

  14. Device for measuring the total concentration of oxygen in gases

    DOE Patents [OSTI]

    Isaacs, Hugh S.; Romano, Anthony J.

    1977-01-01

    This invention provides a CO equilibrium in a device for measuring the total concentration of oxygen impurities in a fluid stream. To this end, the CO equilibrium is produced in an electrochemical measuring cell by the interaction of a carbon element in the cell with the chemically combined and uncombined oxygen in the fluid stream at an elevated temperature.

  15. Homogeneously dispersed, multimetal oxygen-evolving catalysts

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Bo; Zheng, Xueli; Voznyy, Oleksandr; Comin, Riccardo; Bajdich, Michal; Garcia-Melchor, Max; Han, Lili; Xu, Jixian; Liu, Min; Zheng, Lirong; et al

    2016-03-24

    Earth-abundant first-row (3d) transition-metal-based catalysts have been developed for the oxygen-evolution reaction (OER); however, they operate at overpotentials significantly above thermodynamic requirements. Density functional theory suggested that non-3d high-valency metals such as tungsten can modulate 3d metal oxides, providing near-optimal adsorption energies for OER intermediates. We developed a room-temperature synthesis to produce gelled oxy-hydroxide materials with an atomically homogeneous metal distribution. These gelled FeCoW oxy-hydroxide exhibits the lowest overpotential (191 mV) reported at 10 mA per square centimeter in alkaline electrolyte. Here, the catalyst shows no evidence of degradation following more than 500 hours of operation. X-ray absorption and computationalmore » studies reveal a synergistic interplay between W, Fe and Co in producing a favorable local coordination environment and electronic structure that enhance the energetics for OER.« less

  16. Nanoparticulate-catalyzed oxygen transfer processes

    DOE Patents [OSTI]

    Hunt, Andrew T.; Breitkopf, Richard C.

    2009-12-01

    Nanoparticulates of oxygen transfer materials that are oxides of rare earth metals, combinations of rare earth metals, and combinations of transition metals and rare earth metals are used as catalysts in a variety of processes. Unexpectedly large thermal efficiencies are achieved relative to micron sized particulates. Processes that use these catalysts are exemplified in a multistage reactor. The exemplified reactor cracks C6 to C20 hydrocarbons, desulfurizes the hydrocarbon stream and reforms the hydrocarbons in the stream to produce hydrogen. In a first reactor stage the steam and hydrocarbon are passed through particulate mixed rare earth metal oxide to crack larger hydrocarbon molecules. In a second stage, the steam and hydrocarbon are passed through particulate material that desulfurizes the hydrocarbon. In a third stage, the hydrocarbon and steam are passed through a heated, mixed transition metal/rare earth metal oxide to reform the lower hydrocarbons and thereby produce hydrogen. Stages can be alone or combined. Parallel reactors can provide continuous reactant flow. Each of the processes can be carried out individually.

  17. Willamette Oxygen Supplementation Studies : Annual Report 1994.

    SciTech Connect (OSTI)

    Ewing, R.D.; Ewing, S.K.; Sheahan, J.E.

    1994-09-01

    Hydropower development and operations in the Columbia River basin have caused the loss of 5 million to 11 million salmonids. An interim goal of the Northwest Power Planning Council is to reestablish these historical numbers by doubling the present runs from 2.5 million adult fish to 5.0 million adult fish. This increase in production will be accomplished through comprehensive management of both wild and hatchery fish, but artificial propagation will play a major role in the augmentation process. The current husbandry techniques in existing hatcheries require improvements that may include changes in rearing densities, addition of oxygen, removal of excess nitrogen, and improvement in raceway design. Emphasis will be placed on the ability to increase the number of fish released from hatcheries that survive to return as adults. Rearing density is one of the most important elements in fish culture. Fish culturists have attempted to rear fish in hatchery ponds at densities that most efficiently use the rearing space available. Such efficiency studies require a knowledge of cost of rearing and the return of adults to the fisheries and to the hatchery.

  18. Direct tuyere injection of oxygen for enhanced coal combustion

    SciTech Connect (OSTI)

    Riley, M.F.

    1996-12-31

    Injecting oxygen directly into the tuyere blowpipe can enhance the ignition and combustion of injected pulverized coal, allowing the efficient use of higher coal rates at high furnace production levels. The effects of direct oxygen injection have been estimated from an analysis of the factors controlling the dispersion, heating, ignition, and combustion of injected coal. Injecting ambient temperature oxygen offers mechanical improvements in the dispersion of coal but provides little thermochemical benefit over increased blast enrichment. Injecting hot oxygen through a novel, patented thermal nozzle lance offers both mechanical and thermochemical benefits over increased enrichment or ambient oxygen injection. Plans for pilot-scale and commercial-scale testing of this new lance are described.

  19. Effects of electromagnetic field stimulation on cellular signal transduction mechanisms: Analyses of the effects of low frequency electromagnetic fields on calcium spiking in ROS 17/2.8 cells. Final report

    SciTech Connect (OSTI)

    Sisken, B.F.; Sisken, J.E.

    1997-12-01

    The general goals of this work were to determine whether resting levels of cellular second messengers, especially calcium, are affected by low-level electromagnetic fields and the mechanisms that could lead to such changes. The work performed was directed at (1) verifying the report of McLeod et al (1990) that low frequency sinusoidal EMF can alter basal calcium fluctuations in cultured ROS 17/2.8 osteoblast-like cells and (2) reproducing the findings of Luben et al (1982) that pulsed electromagnetic fields can affect PTH-stimulated adenylate cyclase activity in osteoblasts. Initially a system was constructed so that cells could be exposed to sinusoidal electric fields using platinum electrodes. In this system, the electrodes were separated from the cells and culture medium by agar barriers. A series of experiments indicated that this system was subject to a significant, though little-known artifact in which a not well understood interaction between the electrodes and sodium ions in the medium or in plain salt solutions led to frequency and amplitude dependent emission of photons that are recorded by the detection system. They therefore designed and constructed an air gap reactor system that utilizes a ferromagnetic core to direct the magnetic flux generated by a sinusoidal coil. Studies on the effects of a 15 Hz pulsed electromagnetic field (PEMF) on cyclic AMP metabolism were performed on ROS 17/2.8 and MC3T3 cells.

  20. Effect of Oxygen Defects on the Catalytic Performance of VOx/CeO2 Catalysts for Oxidative Dehydrogenation of Methanol

    SciTech Connect (OSTI)

    Li, Yan; Wei, Zhehao; Gao, Feng; Kovarik, Libor; Baylon, Rebecca A.; Peden, Charles HF; Wang, Yong

    2015-05-01

    In this work, CeO2 nanocubes with controlled particle size and dominating (100) facets are synthesized as supports for VOx catalysts. Combined TEM, SEM, XRD, and Raman study reveals that the oxygen vacancy density of CeO2 supports can be tuned by tailoring the particle sizes without altering the dominating facets, where smaller particle sizes result in larger oxygen vacancy densities. At the same vanadium coverage, the VOx catalysts supported on small-sized CeO2 supports with higher oxygen defect densities exhibit promoted redox property and lower activation energy for methoxyl group decomposition, as evidenced by H2-TPR and methanol TPD study. These results further confirm that the presence of oxygen vacancies plays an important role in promoting the activity of VOx species in methanol oxidation. We gratefully acknowledge financial support from the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences. Part of this work was conducted in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is a multiprogram national laboratory operated for the DOE by Battelle.

  1. Oxygen vacancy migration in disordered Gd{sub 2}(Zr{sub x}Ti{sub 1{minus}x}){sub 2}O{sub 7}

    SciTech Connect (OSTI)

    Williford, R.E.; Weber, W.J.; Devanathan, R.; Gale, J.D.

    1999-07-01

    Oxygen vacancy formation and migration energies in the pyrochlores Gd{sub 2}(Zr{sub x}Ti{sub 1{minus}x}){sub 2}O{sub 7} were computed using atomistic energy minimization methods, with particular attention to the role of cation antisite disorder. The interatomic potentials recognize oxygens in distinct crystallographic sites (polarizations) as distinct species, and permit assessment of the directional anisotropy in vacancy migration energies. Oxygen vacancy migration is determined by O{sub 48f} {minus} O{sub 48f} transitions along the shortest edges of the TiO{sub 6} octahedra, in agreement with previous results. Oxygen vacancies migrate towards disorder to reduce local stresses. In contrast to previous work, the V{sub 08a} and V{sub O8a} + I{sub O8b} Frenkel defects are favored over the V{sub O48f} and V{sub O48f} + I{sub O8b} Frenkel. The transition V{sub O8a}{minus}> V{sub O48f} is energetically favored for the ordered structure, and activates the three dimensional O{sub 48f} {minus} O{sub 48f} vacancy migration network by filling empty 9a sites with 48f oxygens. Local regions of order and moderate disorder must both be present for optimum oxygen conductivity. High disorder retards vacancy migration.

  2. Enhancing perovskite electrocatalysis through strain tuning of oxygen deficiency

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Barron, Sara C.; Lee, Ho Nyung; Petrie, Jonathan R.; Jeen, Hyoungjeen; Meyer, Tricia L.

    2016-05-27

    Oxygen vacancies in transition-metal oxides facilitate catalysis critical for energy storage and generation. However, promoting vacancies at the lower temperatures required for operation in devices such as metal–air batteries and portable fuel cells has proven elusive. Here we used thin films of perovskite-based strontium cobaltite (SrCoOx) to show that epitaxial strain is a powerful tool for manipulating the oxygen content under conditions consistent with the oxygen evolution reaction, yielding increasingly oxygen-deficient states in an environment where the cobaltite would normally be fully oxidized. The additional oxygen vacancies created through tensile strain enhance the cobaltite’s catalytic activity toward this important reactionmore » by over an order of magnitude, equaling that of precious-metal catalysts, including IrO2. Lastly, our findings demonstrate that strain in these oxides can dictate the oxygen stoichiometry independent of ambient conditions, allowing unprecedented control over oxygen vacancies essential in catalysis near room temperature.« less

  3. Flammability of selected heat resistant alloys in oxygen gas mixtures

    SciTech Connect (OSTI)

    Zawierucha, R.; McIlroy, K.; Million, J.F.

    1995-12-31

    Within recent years, the use of oxygen has increased in applications where elevated temperatures and corrosion may be significant factors. In such situations, traditional alloys used in oxygen systems will not be adequate. Where alternative alloys must be utilized, based upon environmental requirements, it is essential that they may be characterized with respect to their ignition and combustion resistance in oxygen. Promoted ignition and promoted ignition-combustion are terms which have been used to describe a situation where a substance with low oxygen supports the combustion of a compatibility ignites and more ignition resistant material. In this paper, data will be presented on the promoted ignition-combustion behavior of selected heat resistant engineering alloys that may be considered for gaseous oxygen applications in severe environments. In this investigation, alloys have been evaluated via both flowing and static (fixed volume) approaches using a rod configuration. Oxygen-nitrogen gas mixtures with compositions ranging from approximately 40 to 99.7% oxygen at pressures of 3.55 to 34.6 MPa were used in the comparative studies.

  4. THERMOCHEMICAL CONVERSION OF FERMENTATION-DERIVED OXYGENATES TO FUELS

    SciTech Connect (OSTI)

    Ramasamy, Karthikeyan K.; Wang, Yong

    2013-06-01

    At present ethanol generated from renewable resources through fermentation process is the dominant biofuel. But ethanol suffers from undesirable fuel properties such as low energy density and high water solubility. The production capacity of fermentation derived oxygenates are projected to rise in near future beyond the current needs. The conversion of oxygenates to hydrocarbon compounds that are similar to gasoline, diesel and jet fuel is considered as one of the viable option. In this chapter the thermo catalytic conversion of oxygenates generated through fermentation to fuel range hydrocarbons will be discussed.

  5. Hydrogen Production Using Hydrogenase-Containing Oxygenic Photosynthetic Organisms

    DOE Patents [OSTI]

    Melis, A.; Zhang, L.; Benemann, J. R.; Forestier, M.; Ghirardi, M.; Seibert, M.

    2006-01-24

    A reversible physiological process provides for the temporal separation of oxygen evolution and hydrogen production in a microorganism, which includes the steps of growing a culture of the microorganism in medium under illuminated conditions to accumulate an endogenous substrate, depleting from the medium a nutrient selected from the group consisting of sulfur, iron, and/or manganese, sealing the culture from atmospheric oxygen, incubating the culture in light whereby a rate of light-induced oxygen production is equal to or less than a rate of respiration, and collecting an evolved gas. The process is particularly useful to accomplish a sustained photobiological hydrogen gas production in cultures of microorganisms, such as Chlamydomonas reinhardtii.

  6. Modelling oxygen self-diffusion in UO2 under pressure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cooper, Michael William D.; Grimes, R. W.; Fitzpatrick, M. E.; Chroneos, A.

    2015-10-22

    Access to values for oxygen self-diffusion over a range of temperatures and pressures in UO2 is important to nuclear fuel applications. Here, elastic and expansivity data are used in the framework of a thermodynamic model, the cBΩ model, to derive the oxygen self-diffusion coefficient in UO2 over a range of pressures (0–10 GPa) and temperatures (300–1900 K). Furthermore, the significant reduction in oxygen self-diffusion as a function of increasing hydrostatic pressure, and the associated increase in activation energy, is identified.

  7. Solid phases of spatially nanoconfined oxygen: A neutron scattering study

    SciTech Connect (OSTI)

    Kojda, Danny [Helmholtz-Zentrum Berlin fr Materialien und Energie GmbH, 14109 Berlin (Germany) [Helmholtz-Zentrum Berlin fr Materialien und Energie GmbH, 14109 Berlin (Germany); Freie Universitt Berlin, 14195 Berlin (Germany); Wallacher, Dirk; Hofmann, Tommy, E-mail: tommy.hofmann@helmholtz-berlin.de [Helmholtz-Zentrum Berlin fr Materialien und Energie GmbH, 14109 Berlin (Germany)] [Helmholtz-Zentrum Berlin fr Materialien und Energie GmbH, 14109 Berlin (Germany); Baudoin, Simon; Hansen, Thomas [Institut Laue-Langevin, BP 156, 38042 Grenoble Cedex 9 (France)] [Institut Laue-Langevin, BP 156, 38042 Grenoble Cedex 9 (France); Huber, Patrick [Technische Universitt Hamburg-Harburg, 21073 Hamburg (Germany)] [Technische Universitt Hamburg-Harburg, 21073 Hamburg (Germany)

    2014-01-14

    We present a comprehensive neutron scattering study on solid oxygen spatially confined in 12 nm wide alumina nanochannels. Elastic scattering experiments reveal a structural phase sequence known from bulk oxygen. With decreasing temperature cubic ?-, orthorhombic ?- and monoclinic ?-phases are unambiguously identified in confinement. Weak antiferromagnetic ordering is observed in the confined monoclinic ?-phase. Rocking scans reveal that oxygen nanocrystals inside the tubular channels do not form an isotropic powder. Rather, they exhibit preferred orientations depending on thermal history and the very mechanisms, which guide the structural transitions.

  8. Hydrogen production using hydrogenase-containing oxygenic photosynthetic organisms

    DOE Patents [OSTI]

    Melis, Anastasios; Zhang, Liping; Benemann, John R.; Forestier, Marc; Ghirardi, Maria; Seibert, Michael

    2006-01-24

    A reversible physiological process provides for the temporal separation of oxygen evolution and hydrogen production in a microorganism, which includes the steps of growing a culture of the microorganism in medium under illuminated conditions to accumulate an endogenous substrate, depleting from the medium a nutrient selected from the group consisting of sulfur, iron, and/or manganese, sealing the culture from atmospheric oxygen, incubating the culture in light whereby a rate of light-induced oxygen production is equal to or less than a rate of respiration, and collecting an evolved gas. The process is particularly useful to accomplish a sustained photobiological hydrogen gas production in cultures of microorganisms, such as Chlamydomonas reinhardtii.

  9. Boron nitride nanosheets as oxygen-atom corrosion protective coatings

    SciTech Connect (OSTI)

    Yi, Min; Shen, Zhigang; Zhao, Xiaohu; Liang, Shuaishuai; Liu, Lei

    2014-04-07

    The research of two-dimensional nanomaterials for anticorrosion applications is just recently burgeoning. Herein, we demonstrate the boron nitride nanosheets (BNNSs) coatings for protecting polymer from oxygen-atom corrosion. High-quality BNNSs, which are produced by an effective fluid dynamics method with multiple exfoliation mechanisms, can be assembled into coatings with controlled thickness by vacuum filtration. After exposed in atom oxygen, the naked polymer is severely corroded with remarkable mass loss, while the BNNSs-coated polymer remains intact. Barrier and bonding effects of the BNNSs are responsible for the coating's protective performance. These preliminary yet reproducible results pave a way for resisting oxygen-atom corrosion.

  10. Tritons and tritides as the solute and diffusing species in ceramic tritium breeders

    SciTech Connect (OSTI)

    Fischer, A.K.; Johnson, C.E.

    1988-06-01

    Intragranular diffusion of tritium is one component of the overall process for tritium release from lithium-containing ceramics that may be used to breed tritium in a fusion reactor. The nature of this transport is reviewed in terms of the understanding established for the mechanism of hydrogen migration in other oxides. In this mechanism, the diffusing species is the proton, which moves from oxide ion to oxide ion, thereby giving rise to apparent hydroxide migration. Analogously, at high oxygen activity, the tritio, transiently bonded to successive oxides and forming successive tritoxides, is taken to be the dominant migrating species in ceramic breeders. In addition, tritide is a significant participant in tritium release at low oxygen activity. The relationship of tritons and tritides as the migration species to the observed release of both reduced and oxidized forms of tritium can be understood in terms of the thermodynamic conditions that prevail. Mechanisms are proposed to rationalize the participation of these species. 29 refs., 3 figs.

  11. Oxygen enriched combustion system performance study. Phase 2: 100 percent oxygen enriched combustion in regenerative glass melters, Final report

    SciTech Connect (OSTI)

    Tuson, G.B.; Kobayashi, H.; Campbell, M.J.

    1994-08-01

    The field test project described in this report was conducted to evaluate the energy and environmental performance of 100% oxygen enriched combustion (100% OEC) in regenerative glass melters. Additional objectives were to determine other impacts of 100% OEC on melter operation and glass quality, and to verify on a commercial scale that an on-site Pressure Swing Adsorption oxygen plant can reliably supply oxygen for glass melting with low electrical power consumption. The tests constituted Phase 2 of a cooperative project between the United States Department of Energy, and Praxair, Inc. Phase 1 of the project involved market and technical feasibility assessments of oxygen enriched combustion for a range of high temperature industrial heating applications. An assessment of oxygen supply options for these applications was also performed during Phase 1, which included performance evaluation of a pilot scale 1 ton per day PSA oxygen plant. Two regenerative container glass melters were converted to 100% OEC operation and served as host sites for Phase 2. A 75 ton per day end-fired melter at Carr-Lowrey Glass Company in Baltimore, Maryland, was temporarily converted to 100% OEC in mid- 1990. A 350 tpd cross-fired melter at Gallo Glass Company in Modesto, California was rebuilt for permanent commercial operation with 100% OEC in mid-1991. Initially, both of these melters were supplied with oxygen from liquid storage. Subsequently, in late 1992, a Pressure Swing Adsorption oxygen plant was installed at Gallo to supply oxygen for 100% OEC glass melting. The particular PSA plant design used at Gallo achieves maximum efficiency by cycling the adsorbent beds between pressurized and evacuated states, and is therefore referred to as a Vacuum/Pressure Swing Adsorption (VPSA) plant.

  12. Role of an Oxygen Vacancy Nanostructure on the Switchable Photovoltaic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Role of an Oxygen Vacancy Nanostructure on the Switchable Photovoltaic Effect in BiFeO3 ... Moreover, a switchable photovoltaic effect and its diode effect have been demonstrated.2 ...

  13. STUDY OF USING OXYGEN-ENRICHED COMBUSTION AIR FOR LOCOMOTIVE...

    Office of Scientific and Technical Information (OSTI)

    ... Evaluation o f Polymeric Membranes for Oxygen-Enrichment of Air, DOEAD- 127 10- 1, U S . ... fLom Gas Turbine Engines, Atmospheric Pollution by Aircraft Engines, AGARD CP-125, Paper ...

  14. An Oxygen Isotope Study Of Silicates In The Larderello Geothermal...

    Open Energy Info (EERE)

    Silicates In The Larderello Geothermal Field, Italy Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: An Oxygen Isotope Study Of Silicates In The...

  15. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Armstrong, M R; Zaug, J M; Grant, C D; Crowhurst, J C; Bastea, S 75...

  16. In-situ generation of oxygen-releasing metal peroxides

    DOE Patents [OSTI]

    Looney, Brian B.; Denham, Miles E.

    2007-01-09

    A method for remediation of contaminants in soil and groundwater is disclosed. The method generates oxygen releasing solids in groundwater or soil by injecting an aqueous energetic oxidant solution containing free radicals, oxidative conditions can be created within or ahead of a contaminant plume. Some contaminants may be remediated directly by reaction with the free radicals. Additionally and more importantly, the free radicals create an oxidative condition whereby native or injected materials, especially metals, are converted to peroxides. These peroxides provide a long-term oxygen reservoir, releasing oxygen relatively slowly over time. The oxygen can enhance microbial metabolism to remediate contaminants, can react with contaminant metals either to form immobile precipitants or to mobilize other metals to permit remediation through leaching techniques. Various injection strategies for injecting the energetic oxidant solution are also disclosed.

  17. Oxygen Control of Atomic Structure and Physical Properties of...

    Office of Scientific and Technical Information (OSTI)

    Properties of SrRuO3 Surfaces Citation Details In-Document Search Title: Oxygen Control of Atomic Structure and Physical Properties of SrRuO3 Surfaces Authors: Tselev, ...

  18. Enhancing SNCR-aided combustion with oxygen addition

    DOE Patents [OSTI]

    Kobayashi, Hisashi; Wu, Kuang Tsai; Bool, III, Lawrence E.

    2004-03-09

    NOx emissions from combustion are reduced, NOx reduction efficiency by SNCR is improved, and other efficiencies are realized, by injecting oxygen into a fuel-rich combustion zone under controlled conditions.

  19. Hybrid membrane--PSA system for separating oxygen from air

    DOE Patents [OSTI]

    Staiger, Chad L.; Vaughn, Mark R.; Miller, A. Keith; Cornelius, Christopher J.

    2011-01-25

    A portable, non-cryogenic, oxygen generation system capable of delivering oxygen gas at purities greater than 98% and flow rates of 15 L/min or more is described. The system consists of two major components. The first component is a high efficiency membrane capable of separating argon and a portion of the nitrogen content from air, yielding an oxygen-enriched permeate flow. This is then fed to the second component, a pressure swing adsorption (PSA) unit utilizing a commercially available, but specifically formulated zeolite compound to remove the remainder of the nitrogen from the flow. The system is a unique gas separation system that can operate at ambient temperatures, for producing high purity oxygen for various applications (medical, refining, chemical production, enhanced combustion, fuel cells, etc . . . ) and represents a significant advance compared to current technologies.

  20. COLLATERAL EFFECTS ON SOLAR NEBULA OXYGEN ISOTOPES DUE TO INJECTION...

    Office of Scientific and Technical Information (OSTI)

    COLLATERAL EFFECTS ON SOLAR NEBULA OXYGEN ISOTOPES DUE TO INJECTION OF sup 26Al BY A NEARBY SUPERNOVA Citation Details In-Document Search Title: COLLATERAL EFFECTS ON SOLAR ...

  1. Vehicle Technologies Office Merit Review 2015: Intake Air Oxygen Sensor

    Office of Energy Efficiency and Renewable Energy (EERE)

    Presentation given by Robert Bosch at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about intake air oxygen sensor.

  2. Vehicle Technologies Office Merit Review 2014: Intake Air Oxygen Sensor

    Broader source: Energy.gov [DOE]

    Presentation given by Robert Bosch at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about intake air oxygen sensors.

  3. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Insights into Oxygen's Role in Lithium Battery Capacity Print Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain oxygen's role in Li-ion charge capacity. Lithium: The Star of Battery Chemistry The

  4. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Insights into Oxygen's Role in Lithium Battery Capacity New Insights into Oxygen's Role in Lithium Battery Capacity Print Monday, 11 July 2016 00:00 Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain

  5. Distributed Reforming of Renewable Liquids via Water Splitting using Oxygen

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Transport Membrane (OTM) (Presentation) | Department of Energy Renewable Liquids via Water Splitting using Oxygen Transport Membrane (OTM) (Presentation) Distributed Reforming of Renewable Liquids via Water Splitting using Oxygen Transport Membrane (OTM) (Presentation) Presented at the 2007 Bio-Derived Liquids to Hydrogen Distributed Reforming Working Group held November 6, 2007 in Laurel, Maryland. 11_anl_distributed_reforming_using_otm.pdf (809.59 KB) More Documents & Publications Cost

  6. Oxygen enhanced switching to combustion of lower rank fuels

    DOE Patents [OSTI]

    Kobayashi, Hisashi; Bool, III, Lawrence E.; Wu, Kuang Tsai

    2004-03-02

    A furnace that combusts fuel, such as coal, of a given minimum energy content to obtain a stated minimum amount of energy per unit of time is enabled to combust fuel having a lower energy content, while still obtaining at least the stated minimum energy generation rate, by replacing a small amount of the combustion air fed to the furnace by oxygen. The replacement of oxygen for combustion air also provides reduction in the generation of NOx.

  7. Hydrogen (H2) Production by Oxygenic Phototrophs | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Oxygenic Phototrophs Hydrogen (H2) Production by Oxygenic Phototrophs Presentation by Eric Hegg, Michigan State University, at the Biological Hydrogen Production Workshop held September 24-25, 2013, at the National Renewable Energy Laboratory in Golden, Colorado. bio_h2_workshop_hegg.pdf (1.07 MB) More Documents & Publications Renewable Hydrogen Production from Biological Systems Autofermentative Biological Hydrogen Production by Cyanobacteria 2013 Biological Hydrogen Production Workshop

  8. Method for making oxygen-reducing catalyst layers

    DOE Patents [OSTI]

    O'Brien, Dennis P.; Schmoeckel, Alison K.; Vernstrom, George D.; Atanasoski, Radoslav; Wood, Thomas E.; O'Neill, David G.

    2010-06-22

    Methods are provided for making oxygen-reducing catalyst layers, which include simultaneous or sequential stops of physical vapor depositing an oxygen-reducing catalytic material onto a substrate, the catalytic material comprising a transition metal that is substantially free of platinum; and thermally treating the catalytic material. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  9. Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium Oxygen Diffusion (OD) Dramatically Improves Wear-Resistance of Titanium 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007, Detroit, Michigan. Sponsored by the U.S. Department of Energy's (DOE) Office of FreedomCAR and Vehicle Technologies (OFCVT). deer07_qu.pdf (724.19 KB) More Documents & Publications Ionic Liquids as Multifunctional Ashless

  10. Oxygen-permeable ceramic membranes for gas separation

    SciTech Connect (OSTI)

    Balachandran, U.; Ma, B.; Maiya, P.S.; Dusek, J.T.; Mieville, R.L.; Picciolo, J.J.

    1998-02-01

    Mixed-conducting oxides have a wide range of applications, including fuel cells, gas separation systems, sensors, and electrocatalytic equipment. Dense ceramic membranes made of mixed-conducting oxides are particularly attractive for gas separation and methane conversion processes. Membranes made of Sr-Fe-Co oxide, which exhibits high combined electronic and oxygen ionic conductivities, can be used to selectively transport oxygen during the partial oxidation of methane to synthesis gas (syngas, i.e., CO + H{sub 2}). The authors have fabricated tubular Sr{sub 2}Fe{sub 2}CoO{sub 6+{delta}} membranes and tested them (some for more than 1,000 h) in a methane conversion reactor that was operating at 850--950 C. An oxygen permeation flux of {approx} 10 scc/cm{sup 2} {center_dot} min was obtained at 900 C in a tubular membrane with a wall thickness of 0.75 mm. Using a gas-tight electrochemical cell, the authors have also measured the steady-state oxygen permeability of flat Sr{sub 2}Fe{sub 2}CoO{sub 6+{delta}} membranes as a function of temperature and oxygen partial pressure(pO{sub 2}). Steady-state oxygen permeability increases with increasing temperature and with the difference in pO{sub 2} on the two sides of the membrane. At 900 C, an oxygen permeability of {approx} 2.5 scc/cm{sup 2} {center_dot} min was obtained in a 2.9-mm-thick membrane. This value agrees with that obtained in methane conversion reactor experiments. Current-voltage (I-V) characteristics determined in the gas-tight cell indicate that bulk effect, rather than surface exchange effect, is the main limiting factor for oxygen permeation of {approx} 1-mm-thick Sr{sub 2}Fe{sub 2}CoO{sub 6+{delta}} membranes at elevated temperatures (> 650 C).

  11. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Insights into Oxygen's Role in Lithium Battery Capacity Print Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain oxygen's role in Li-ion charge capacity. Lithium: The Star of Battery Chemistry The

  12. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Insights into Oxygen's Role in Lithium Battery Capacity Print Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain oxygen's role in Li-ion charge capacity. Lithium: The Star of Battery Chemistry The

  13. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Insights into Oxygen's Role in Lithium Battery Capacity Print Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain oxygen's role in Li-ion charge capacity. Lithium: The Star of Battery Chemistry The

  14. New Insights into Oxygen's Role in Lithium Battery Capacity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Insights into Oxygen's Role in Lithium Battery Capacity Print Researchers working at the ALS have recently made new discoveries in understanding the nature of charge storage in lithium-ion (Li-ion) batteries, opening up possibilities for new battery designs with significantly improved capacity. Looking at a popular Li-rich cathode material, the researchers used soft x-ray techniques to quantifiably explain oxygen's role in Li-ion charge capacity. Lithium: The Star of Battery Chemistry The

  15. Missing Oxygen Atoms Are Key to Robust Spintronic Material

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Missing Oxygen Atoms Are Key to Robust Spintronic Material Missing Oxygen Atoms Are Key to Robust Spintronic Material Print Friday, 01 April 2016 11:44 The endless pursuit of faster, more energy-efficient computers has led to the emergence of the field of spintronics, where the manipulation and detection of electron spins are utilized in electronic circuits. A particular class of materials called dilute magnetic oxides are promising candidates for spintronics applications because they exhibit

  16. Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced

    Office of Scientific and Technical Information (OSTI)

    mixture of nitromethane and hydrogen peroxide (Conference) | SciTech Connect kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Authors: Armstrong, M R ; Zaug, J M ; Grant, C D ; Crowhurst, J C ; Bastea, S Publication Date: 2014-06-24 OSTI Identifier: 1149544 Report Number(s):

  17. Electrochemical transfer of oxygen during direct current arc welding

    SciTech Connect (OSTI)

    Kim, J.H.; Frost, R.H.; Olson, D.L.

    1994-12-31

    Weld metal oxygen content is important for control of weld metal microstructure and notch toughness. Low oxygen contents promote low toughness bainitic structures. Moderate oxygen levels favor a tough acicular ferrite structure, and high oxygen levels promote lower toughness grain boundary and Widmanstaetten side plate structures. The objective of this research was to examine electrochemical oxygen transfer as a function of welding process variables, polarity, and the relative importance of conduction across plasma-metal and slag-metal interfaces for: submerged arc welding (SAW), shielded metal arc welding (SMAW), and gas tungsten arc welding (GTAW) processes. SAW and SMAW were made in DCEN and DCEP polarities on structural steel and copper substrates. GTAW were made on steel substrates in DCEN polarity. The experimental results show that both thermochemical and electrochemical reactions are important for oxygen transfer, and that there are differences in the electrochemical reactions at slag-metal and plasma-metal interfaces. Both electrochemical and thermochemical reactions are significant for direct current arc welding processes. The arc plasma acts as an electrolyte for arc welding processes and electrochemical reactions occur at the plasma-metal interface have chemical effects opposite to those at the slag metal interface. This is caused by the fact that only positive ions exist in the arc plasma in large concentrations.

  18. Influence of Oxygen and pH on the Selective Oxidation of Ethanol on Pd Catalysts

    SciTech Connect (OSTI)

    Hibbitts, David D.; Neurock, Matthew

    2013-03-01

    The selective oxidation of ethanol on supported Pd is catalytically promoted by the presence of hydroxide species on the Pd surface as well as in solution. These hydroxide intermediates act as Brønsted bases which readily abstract protons from the hydroxyl groups of adsorbed or solution-phase alcohols. The C1AH bond of the resulting alkoxide is subsequently activated on the metal surface via hydride elimination to form acetaldehyde. Surface and solution-phase hydroxide intermediates can also readily react with the acetaldehyde via nucleophilic addition to form a germinal diol intermediate, which subsequently undergoes a second C1AH bond activation on Pd to form acetic acid. The role of O2 is to remove the electrons produced in the oxidation reaction via the oxygen reduction reaction over Pd. The reduction reaction also regenerates the hydroxide intermediates and removes adsorbed hydrogen that is produced during the oxidation.

  19. The production of carbon nanofibers and thin films on palladium catalysts from ethylene oxygen mixtures

    SciTech Connect (OSTI)

    Phillips, Jonathan; Doorn, Stephen; Atwater, Mark; Leseman, Zayd; Luhrs, Claudia C; Diez, Yolanda F; Diaz, Angel M

    2009-01-01

    The characteristics of carbonaceous materials deposited in fuel rich ethylene-oxygen mixtures on three types of palladium: foil, sputtered film, and nanopowder, are reported. It was found that the form of palladium has a dramatic influence on the morphology of the deposited carbon. In particular, on sputtered film and powder, tight 'weaves' of sub-micron filaments formed quickly. In contrast, on foils under identical conditions, the dominant morphology is carbon thin films with basal planes oriented parallel to the substrate surface. Temperature, gas flow rate, reactant flow ratio (C2H4:02), and residence time (position) were found to influence both growth rate and type for all three forms of Pd. X-ray diffraction, high-resolution transmission electron microscopy, temperature-programmed oxidation, and Raman spectroscopy were used to assess the crystallinity of the as-deposited carbon, and it was determined that transmission electron microscopy and x-ray diffraction were the most reliable methods for determining crystallinity. The dependence of growth on reactor position, and the fact that no growth was observed in the absence of oxygen support the postulate that the carbon deposition proceeds by combustion generated radical species.

  20. Ozone-forming potential of a series of oxygenated organic compounds

    SciTech Connect (OSTI)

    Japar, S.M.; Wallington, T.J.; Rudy, S.J.; Chang, Tai Y. )

    1991-03-01

    An incremental reactivity approach has been used to assess the relative ozone-forming potentials of various important oxygenated fuels/fuel additives, i.e., tert-butyl alcohol (TBA), dimethyl ether (DME), diethyl ether (DEE), methyl tert-butyl ether (MTBE), and ethyl tert-butyl ether (ETBE), in a variety of environments. Calculations were performed using a single-cell trajectory model, combined with the Lurmann-Carter-Coyner chemical mechanism, with (NMOC)/(NO{sub x}) ratios ranging from 4 to 20. This work provides the first quantitative assessment of the air quality impact of release of these important oxygenated compounds. ETBE and DEE are the two most reactive compounds on a per carbon equivalent basis, while TBA is the least reactive species. At a (NMOC)/(NO{sub x}) ratio of 8, which is generally typical of polluted urban areas in the United States, TBA, DME, MTBE, and ETBE all have incremental reactivities less than or equal to that of the urban NMHC mix. Thus, use of these additives in fuels may have a beneficial impact on urban ozone levels.

  1. Interaction of light with the ZnO surface: Photon induced oxygen breathing, oxygen vacancies, persistent photoconductivity, and persistent photovoltage

    SciTech Connect (OSTI)

    Gurwitz, Ron; Cohen, Rotem; Shalish, Ilan

    2014-01-21

    ZnO surfaces adsorb oxygen in the dark and emit CO{sub 2} when exposed to white light, reminiscent of the lungs of living creatures. We find that this exchange of oxygen with the ambient affects the integrity of the ZnO surface. Thus, it forms a basis for several interesting surface phenomena in ZnO, such as photoconductivity, photovoltage, and gas sensing, and has a role in ZnO electrical conduction. Using x-ray photoelectron spectroscopy on ZnO nanowires, we observed a decomposition of ZnO under white light and formation of oxygen-depleted surface, which explains photoconductivity by the electron donation of oxygen vacancies. Our findings suggest that the observed decomposition of the ZnO lattice may only take place due to photon-induced reduction of ZnO by carbon containing molecules (or carbo-photonic reduction), possibly from the ambient gas, accounting in a consistent way for both the reduced demands on the energy required for decomposition and for the observed emission of lattice oxygen in the form of CO{sub 2}. The formation of oxygen-vacancy rich surface is suggested to induce surface delta doping, causing accumulation of electrons at the surface, which accounts for both the increase in conductivity and the flattening of the energy bands. Using surface photovoltage spectroscopy in ultra high vacuum, we monitored changes in the deep level spectrum. We observe a wide optical transition from a deep acceptor to the conduction band, which energy position coincides with the position of the so called green luminescence in ZnO. This green transition disappears with the formation of surface oxygen vacancies. Since the oxygen vacancies are donors, while the green transition involves surface acceptors, the results suggest that the initial emission of oxygen originates at the defect sites of the latter, thereby eliminating each other. This suggests that the green transition originates at surface Zn vacancy acceptors. Removing an oxygen atom from a Zn vacancy

  2. Genomic definition of species. Revision 1

    SciTech Connect (OSTI)

    Crkvenjakov, R.; Dramanac, R.

    1992-06-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called (species) genome. The definition of species based on chromosomes, genes, or genome common to its member organisms has been implied or mentioned in passing numerous times. Some population biologists think that members of species have similar ``homeostatic genotypes,`` which are to a degree resistant to mutation or environmental change in the production of a basic phenotype.

  3. Genomic definition of species. Revision 2

    SciTech Connect (OSTI)

    Crkvenjakov, R.; Drmanac, R.

    1993-03-01

    A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.

  4. Reactions of platinum in oxygen- and hydrogen-treated Pt/. gamma. -Al/sub 2/O/sub 3/ catalysts. II. Ultraviolet-visible studies, sintering of platinum, and soluble platinum

    SciTech Connect (OSTI)

    Lietz, G.; Lieske, H.; Spindler, H.; Hanke, W.; Voelter, J.

    1983-05-01

    Alumina-supported platinum (Pt/..gamma..-Al/sub 2/O/sub 3/) catalysts treated in oxygen between 100 and 600/sup 0/C and in hydrogen at 500/sup 0/C were studied by uv-vis reflectance spectroscopy. The formation of different oxidized Pt surface species previously indicated by temperature programmed reduction (TPR) studies (H. Lieske, G. Lietz, H. Spindler, and J. Voelter, J. Catal. 81, 8(1983)) was confirmed by characteristic uv-vis spectra. The results are used as the basis for a model describing the types of surface reactions and details of the platinum surface species formed in oxygen and in hydrogen, and for a model of the sintering in oxygen. The amount of soluble platinum was found to correspond with the amount of highly dispersed platinum. Hence, only surface platinum atoms are soluble. 16 figures.

  5. High fidelity modeling of thermal relaxation and dissociation of oxygen

    SciTech Connect (OSTI)

    Andrienko, Daniil A. Boyd, Iain D.

    2015-11-15

    A master equation study of vibrational relaxation and dissociation of oxygen is conducted using state-specific O{sub 2}–O transition rates, generated by extensive trajectory simulations. Both O{sub 2}–O and O{sub 2}–O{sub 2} collisions are concurrently simulated in the evolving nonequilibrium gas system under constant heat bath conditions. The forced harmonic oscillator model is incorporated to simulate the state-to-state relaxation of oxygen in O{sub 2}–O{sub 2} collisions. The system of master equations is solved to simulate heating and cooling flows. The present study demonstrates the importance of atom-diatom collisions due to the extremely efficient energy randomization in the intermediate O{sub 3} complex. It is shown that the presence of atomic oxygen has a significant impact on vibrational relaxation time at temperatures observed in hypersonic flow. The population of highly-excited O{sub 2} vibrational states is affected by the amount of atomic oxygen when modeling the relaxation under constant heat bath conditions. A model of coupled state-to-state vibrational relaxation and dissociation of oxygen is also discussed.

  6. Surface control of epitaxial manganite films via oxygen pressure

    SciTech Connect (OSTI)

    Tselev, Alexander; Vasudevan, Rama K.; Gianfrancesco, Anthony G.; Qiao, Liang; Ganesh, Panchapakesan; Meyer, Tricia L.; Lee, Ho Nyung; Biegalski, Michael D.; Baddorf, Arthur P.; Kalinin, Sergei

    2015-03-11

    The trend to reduce device dimensions demands increasing attention to atomic-scale details of structure of thin films as well as to pathways to control it. We found that this is of special importance in the systems with multiple competing interactions. We have used in situ scanning tunneling microscopy to image surfaces of La5/8Ca3/8MnO3 films grown by pulsed laser deposition. The atomically resolved imaging was combined with in situ angle-resolved X-ray photoelectron spectroscopy. We find a strong effect of the background oxygen pressure during deposition on structural and chemical features of the film surface. Deposition at 50 mTorr of O2 leads to mixed-terminated film surfaces, with B-site (MnO2) termination being structurally imperfect at the atomic scale. Moreover, a relatively small reduction of the oxygen pressure to 20 mTorr results in a dramatic change of the surface structure leading to a nearly perfectly ordered B-site terminated surface with only a small fraction of A-site (La,Ca)O termination. This is accompanied, however, by surface roughening at a mesoscopic length scale. The results suggest that oxygen has a strong link to the adatom mobility during growth. The effect of the oxygen pressure on dopant surface segregation is also pronounced: Ca surface segregation is decreased with oxygen pressure reduction.

  7. Surface control of epitaxial manganite films via oxygen pressure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tselev, Alexander; Vasudevan, Rama K.; Gianfrancesco, Anthony G.; Qiao, Liang; Ganesh, Panchapakesan; Meyer, Tricia L.; Lee, Ho Nyung; Biegalski, Michael D.; Baddorf, Arthur P.; Kalinin, Sergei

    2015-03-11

    The trend to reduce device dimensions demands increasing attention to atomic-scale details of structure of thin films as well as to pathways to control it. We found that this is of special importance in the systems with multiple competing interactions. We have used in situ scanning tunneling microscopy to image surfaces of La5/8Ca3/8MnO3 films grown by pulsed laser deposition. The atomically resolved imaging was combined with in situ angle-resolved X-ray photoelectron spectroscopy. We find a strong effect of the background oxygen pressure during deposition on structural and chemical features of the film surface. Deposition at 50 mTorr of O2 leadsmore » to mixed-terminated film surfaces, with B-site (MnO2) termination being structurally imperfect at the atomic scale. Moreover, a relatively small reduction of the oxygen pressure to 20 mTorr results in a dramatic change of the surface structure leading to a nearly perfectly ordered B-site terminated surface with only a small fraction of A-site (La,Ca)O termination. This is accompanied, however, by surface roughening at a mesoscopic length scale. The results suggest that oxygen has a strong link to the adatom mobility during growth. The effect of the oxygen pressure on dopant surface segregation is also pronounced: Ca surface segregation is decreased with oxygen pressure reduction.« less

  8. Real-time optical diagnostics for the basic oxygen steelmaking process

    SciTech Connect (OSTI)

    Ottesen, D.K.; Hurt, R.H.; Hardesty, D.R.

    1993-02-01

    This article deals with the development of real-time optical diagnostic techniques for process control in basic oxygen steelmaking. Results are presented of pilot-scale feasibility experiments conducted in the two-ton basic oxygen furnace (BOF) at Bethlehem Steel Corporation`s Homer Research Laboratories. Two line-of-sight optical techniques are being evaluated for determining the concentration and temperature of infrared-active gases in the BOF off-gas. The primary objective is to relate the concentration of these gas-phase species to the carbon content of the molten metal, and thereby provide a real-time indication of the process endpoint. Three cw lasers were used to measure the extent of beam attenuation at three different wavelengths in the particle-laden off-gas. The primary attenuation mechanism appears to be scattering by a dense, sub-micron diameter FeO fume. Initial infrared emission experiments with a Fourier transform infrared spectrometer at 1-cm{sup {minus}1} spectral resolution show partially resolved lines in the P-branch of the fundamental CO ground state and first hot-band transitions; CO{sub 2} bandheads are also clearly observed at 2384 and 2397 cm{sup {minus}1}. A second set of experiments was conducted to test the feasibility of oxygen-lance based fiber-optic imaging/pyrometric sensors for measurements of melt temperature and reaction zone properties. During bottom injection of nitrogen, clearly defined images of the melt/slag surface were obtained using both visible and near-infrared video systems. During oxygen blowing, optical emission from the hot spot was observed to fluctuate widely, with characteristic frequencies in the range of 3--10 Hz. Near the end of the process, the emission is characterized by periodic intensity bursts, interpreted as individual ignition events of duration 10--50 msec. Hot spot temperatures were calculated from the emission at 800 and 950 nm wavelengths using a grey-body assumption.

  9. Diffusion and Adsorption of Uranyl Carbonate Species in Nanosized Mineral Fractures

    SciTech Connect (OSTI)

    Kerisit, Sebastien N.; Liu, Chongxuan

    2012-02-07

    Atomistic simulations were performed to study the diffusion and adsorption of Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3} and of some of its constituent species, i.e., UO{sub 2}{sup 2+}, CO{sub 3}{sup 2-}, and UO{sub 2}CO{sub 3}, in feldspar nano-sized fractures. Feldspar is important to uranium remediation efforts at the U.S. Department of Energy Hanford site as it has been found in recent studies to host contaminants within its intragrain fractures. In addition, uranyl carbonate species are known to dominate U(VI) speciation in conditions relevant to the Hanford site. Molecular dynamics (MD) simulations showed that the presence of the feldspar surface diminishes the diffusion coefficients of all the species considered in this work and that the diffusion coefficients do not reach their bulk aqueous solution values in the center of a 2.5 nm fracture. Moreover, the MD simulations showed that the rate of decrease in the diffusion coefficients with decreasing distance from the surface is greater for larger adsorbing species. Free energy profiles of the same species adsorbing on the feldspar surface revealed a large exothermic free energy of adsorption for UO{sub 2}{sup 2+} and UO{sub 2}CO{sub 3}, which are able to adsorb to the surface with their uranium atom directly bonded to a surface hydroxyl oxygen, whereas adsorption of CO{sub 3}{sup 2-} and Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3}, which attach to the surface via hydrogen bonding from a surface hydroxyl group to a carbonate oxygen, was calculated to be either only slightly exothermic or endothermic.

  10. Method and apparatus for producing oxygenates from hydrocarbons

    DOE Patents [OSTI]

    Kong, Peter C.; Lessing, Paul A.

    1995-01-01

    A chemical reactor for oxygenating hydrocarbons includes: a) a dielectric barrier discharge plasma cell, the plasma cell comprising a pair of electrodes having a dielectric material and void therebetween, the plasma cell comprising a hydrocarbon gas inlet feeding to the void; b) a solid oxide electrochemical cell, the electrochemical cell comprising a solid oxide electrolyte positioned between a porous cathode and a porous anode, an oxygen containing gas inlet stream feeding to the porous cathode side of the electrochemical cell; c) a first gas passageway feeding from the void to the anode side of the electrochemical cell; and d) a gas outlet feeding from the anode side of the electrochemical cell to expel reaction products from the chemical reactor. A method of oxygenating hydrocarbons is also disclosed.

  11. Method and apparatus for producing oxygenates from hydrocarbons

    DOE Patents [OSTI]

    Kong, P.C.; Lessing, P.A.

    1995-06-27

    A chemical reactor for oxygenating hydrocarbons includes: (a) a dielectric barrier discharge plasma cell, the plasma cell comprising a pair of electrodes having a dielectric material and void therebetween, the plasma cell comprising a hydrocarbon gas inlet feeding to the void; (b) a solid oxide electrochemical cell, the electrochemical cell comprising a solid oxide electrolyte positioned between a porous cathode and a porous anode, an oxygen containing gas inlet stream feeding to the porous cathode side of the electrochemical cell; (c) a first gas passageway feeding from the void to the anode side of the electrochemical cell; and (d) a gas outlet feeding from the anode side of the electrochemical cell to expel reaction products from the chemical reactor. A method of oxygenating hydrocarbons is also disclosed. 4 figs.

  12. CRADA Final Report: Ionically Conductive Membranes Oxygen Separation

    SciTech Connect (OSTI)

    Visco, Steven J.

    2001-10-29

    Scientists at the Lawrence Berkeley National Laboratory (LBNL) in a collaborative effort with Praxair Corporation developed a bench-top oxygen separation unit capable of producing ultra-high purity oxygen from air. The device is based on thin-film electrolyte technology developed at LBNL as part of a solid oxide fuel cell program. The two teams first demonstrated the concept using planar ceramic disks followed by the development of tubular ceramic structures for the bench-top unit. The highly successful CRADA met all technical milestones on time and on budget. Due to the success of this program the industrial partner and the team at LBNL submitted a grant proposal for further development of the unit to the Advanced Technology Program administered by the National Institute of Standar~s. This proposal was selected for funding, and now the two teams are developing a precommercial oxygen separation unit under a 3-year, $6 million dollar program.

  13. Fuel and oxygen addition for metal smelting or refining process

    DOE Patents [OSTI]

    Schlichting, Mark R.

    1994-01-01

    A furnace 10 for smelting iron ore and/or refining molten iron 20 is equipped with an overhead pneumatic lance 40, through which a center stream of particulate coal 53 is ejected at high velocity into a slag layer 30. An annular stream of nitrogen or argon 51 enshrouds the coal stream. Oxygen 52 is simultaneously ejected in an annular stream encircling the inert gas stream 51. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus 84 to react with carbon monoxide gas rising from slag layer 30, thereby adding still more heat to the furnace.

  14. Fuel and oxygen addition for metal smelting or refining process

    DOE Patents [OSTI]

    Schlichting, M.R.

    1994-11-22

    A furnace for smelting iron ore and/or refining molten iron is equipped with an overhead pneumatic lance, through which a center stream of particulate coal is ejected at high velocity into a slag layer. An annular stream of nitrogen or argon enshrouds the coal stream. Oxygen is simultaneously ejected in an annular stream encircling the inert gas stream. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus to react with carbon monoxide gas rising from slag layer, thereby adding still more heat to the furnace. 7 figs.

  15. Impact of oxygenates on petroleum refining, review and forecast

    SciTech Connect (OSTI)

    Unzelman, G.H.

    1995-09-01

    During the coming decade, oxygenates will continue to impact light oil processing and will steadily change the composition of the US gasoline pool. There are several major driving forces that will sustain the gradual influx of oxygen to US gasoline toward the regulatory limits: (1) the positive environmental characteristics of oxygenated compounds, (2) the high-octane quality of ethers that promote elimination of less desirable hydrocarbons and (3) the competitive need for ultra-clean gasoline to compete with alternatives. From 1995 forward, conventional gasoline will gradually shift to RFG (reformulated gasoline) containing a minimum of 2 wt% oxygen and less aromatics. As a result some processing changes, already in motion in the refining industry, will continue. For example, less severe naphtha reforming and cracking innovations to yield more feed for etherification and alkylation. While alternative fuel and vehicle technology will continue to develop, oxygenates in US gasoline will contribute the major alternative dimension to transportation fuel in the foreseeable future. With RFG, internal-combustion engine emissions will be progressively less toxic and lower in photochemical reactivity. The oxygenate mix will favor methyl ethers in spite of the recent methanol price spike. Ethyl ethers will be used on a more limited basis for specific situations where lower volatility and feedstock economics are an advantage. Downstream blending of ethanol will supplement ethers blended at the refinery in situations where economics are more favorable than refinery ethers. Long-range survival of ethanol, as a direct blending agent or feedstock for refinery ethers, depends on one or more of several factors: future crude oil costs, longevity of subsidies and/or mandates, and new production technology based on cellulose yielding ethanol economically competitive with hydrocarbons.

  16. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates New Species of Cyanobacteria Forms Intracellular Carbonates Print Wednesday, 30 January 2013 00:00 A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the Mexican Lake of Alchichica where massive carbonate rocks form. Cyanobacteria have been impacting the global carbon cycle of the Earth for more than 2.3 billion years by assimilating CO2 into organic compounds and triggering

  17. Endangered Species Act | Open Energy Information

    Open Energy Info (EERE)

    species and the ecosystems upon which they depend. It is administered by the U.S. Fish and Wildlife Service and the Commerce Department's National Marine Fisheries Service...

  18. Blood storage device and method for oxygen removal

    DOE Patents [OSTI]

    Bitensky, Mark W.; Yoshida, Tatsuro

    2000-01-01

    The present invention relates to a storage device and method for the long-term storage of blood and, more particularly, to a blood storage device and method capable of removing oxygen from the stored blood and thereby prolonging the storage life of the deoxygenated blood.

  19. Process for conversion of lignin to reformulated, partially oxygenated gasoline

    DOE Patents [OSTI]

    Shabtai, Joseph S. (Salt Lake City, UT); Zmierczak, Wlodzimierz W. (Salt Lake City, UT); Chornet, Esteban (Golden, CO)

    2001-01-09

    A high-yield process for converting lignin into reformulated, partially oxygenated gasoline compositions of high quality is provided. The process is a two-stage catalytic reaction process that produces a reformulated, partially oxygenated gasoline product with a controlled amount of aromatics. In the first stage of the process, a lignin feed material is subjected to a base-catalyzed depolymerization reaction, followed by a selective hydrocracking reaction which utilizes a superacid catalyst to produce a high oxygen-content depolymerized lignin product mainly composed of alkylated phenols, alkylated alkoxyphenols, and alkylbenzenes. In the second stage of the process, the depolymerized lignin product is subjected to an exhaustive etherification reaction, optionally followed by a partial ring hydrogenation reaction, to produce a reformulated, partially oxygenated/etherified gasoline product, which includes a mixture of substituted phenyl/methyl ethers, cycloalkyl methyl ethers, C.sub.7 -C.sub.10 alkylbenzenes, C.sub.6 -C.sub.10 branched and multibranched paraffins, and alkylated and polyalkylated cycloalkanes.

  20. Utilization of Renewable Oxygenates as Gasoline Blending Components

    SciTech Connect (OSTI)

    Yanowitz, J.; Christensen, E.; McCormick, R. L.

    2011-08-01

    This report reviews the use of higher alcohols and several cellulose-derived oxygenates as blend components in gasoline. Material compatibility issues are expected to be less severe for neat higher alcohols than for fuel-grade ethanol. Very little data exist on how blending higher alcohols or other oxygenates with gasoline affects ASTM Standard D4814 properties. Under the Clean Air Act, fuels used in the United States must be 'substantially similar' to fuels used in certification of cars for emission compliance. Waivers for the addition of higher alcohols at concentrations up to 3.7 wt% oxygen have been granted. Limited emission testing on pre-Tier 1 vehicles and research engines suggests that higher alcohols will reduce emissions of CO and organics, while NOx emissions will stay the same or increase. Most oxygenates can be used as octane improvers for standard gasoline stocks. The properties of 2-methyltetrahydrofuran, dimethylfuran, 2-methylfuran, methyl pentanoate and ethyl pentanoate suggest that they may function well as low-concentration blends with gasoline in standard vehicles and in higher concentrations in flex fuel vehicles.

  1. Materials and methods for the separation of oxygen from air

    DOE Patents [OSTI]

    MacKay, Richard; Schwartz, Michael; Sammells, Anthony F.

    2003-07-15

    Metal oxides particularly useful for the manufacture of catalytic membranes for gas-phase oxygen separation processes having the formula: O.sub.5+z where: x and x' are greater than 0; y and y' are greater than 0; x+x' is equal to 2; y+y' is less than or equal to 2; z is a number that makes the metal oxide charge neutral; A is an element selected from the lanthanide elements; A' is an element selected from Be, Mg, Ca, Sr, Ba and Ra; A" is an element selected from the f block lanthanides, Be, Mg, Ca, Sr, Ba and Ra; B is an element selected from the group consisting of Al, Ga, In or mixtures thereof and B" is Co or Mg, with the exception that when B" is Mg, A' and A" are not Mg. The metal oxides are useful for preparation of dense membranes which may be formed from dense thin films of the mixed metal oxide on a porous metal oxide element. The invention also provides methods and catalytic reactors for oxygen separation and oxygen enrichment of oxygen deficient gases which employ mixed conducting metal oxides of the above formula.

  2. High-temperature potentiometric oxygen sensor with internal reference

    DOE Patents [OSTI]

    Routbort, Jules L.; Singh, Dileep; Dutta, Prabir K.; Ramasamy, Ramamoorthy; Spirig, John V.; Akbar, Sheikh

    2011-11-15

    A compact oxygen sensor is provided, comprising a mixture of metal and metal oxide an enclosure containing said mixture, said enclosure capable of isolating said mixture from an environment external of said enclosure, and a first wire having a first end residing within the enclosure and having a second end exposed to the environment. Also provided is a method for the fabrication of an oxygen sensor, the method comprising confining a metal-metal oxide solid mixture to a container which consists of a single material permeable to oxygen ions, supplying an electrical conductor having a first end and a second end, whereby the first end resides inside the container as a reference (PO.sub.2).sup.ref, and the second end resides outside the container in the atmosphere where oxygen partial pressure (PO.sub.2).sup.ext is to be measured, and sealing the container with additional single material such that grain boundary sliding occurs between grains of the single material and grains of the additional single material.

  3. Chemistry - Oxygen Vacancies and Catalysis on Ceria Surfaces

    SciTech Connect (OSTI)

    Campbell, Charles T.; Peden, Charles HF.

    2005-07-29

    Chemistry occurring at the surface of metal oxides is critical in a variety of industrial applications including catalysis and photocatalysis, optical display technology, solar energy devices and corrosion prevention. Defects have long been recognized to be the most reactive sites on the surfaces of many oxide materials. The most common types of defects present on the surfaces of metal oxides are oxygen vacancies and step edges. The nature of surface oxygen vacancies, and their number, distribution and diffusion across the surface of oxides, are thus issues of major scientific importance. One of the most interesting oxides in this respect is CeO2, since oxygen vacancies play the key role in giving this material it's industrially important ''oxygen-storage capacity''. This capacity makes modern automotive exhaust treatment catalysts containing CeO2 much more effective than their predecessors without CeO2. Ceria is also well known as a support which enhances the performance of transition metal catalysts, relative to other oxide supports, in a variety of other reactions including water-gas shift, steam reforming of oxygenates and PROX 1-7, all of which hold promise for enabling a hydrogen economy 1. Related to ceria's facile redox capacity (ability to rapidly form and eliminate oxygen vacancy defects) is the poorly understood observation that some less reducible oxides, such as zirconia (ZrO2), are used as additives that actually enhance this ''oxygen storage'' property of CeO2. In this issue, Esch and coworkers in Trieste, Italy report an exciting study that for the first time clearly elucidates the structure, distribution and formation of oxygen vacancies on a cerium oxide surface 8. They have elegantly combined beautiful, atomic-resolution imaging using scanning-tunneling microscopy (STM) on a ceria surface with state-of-the-art quantum mechanical calculations using Density Functional Theory (DFT) to raise our understanding of CeO2 surfaces to a much higher level

  4. Subtask 3.12 - Oxygen-Fired CFBC

    SciTech Connect (OSTI)

    Douglas Hajicek; Mark Musich; Ann Henderson

    2007-02-28

    Traditionally, air is used as the source of oxygen for firing a combustion system. A fully oxygen-fired circulating fluidized-bed combustion (CFBC) system would result in the production of a flue gas stream consisting of mostly carbon dioxide and water. The concentrated carbon dioxide stream would be available for sequestering or other purposes. Temperatures in an oxygen-blown CFBC system would be controlled by a combination of flue gas recycle, solids recirculation, and by appropriately sizing and locating the amount of heat-transfer surface required. Flue gas recycle provides the additional gas required for adequate fluidization and circulation of solids replacing the nitrogen that would be present in an air-blown system. The amount of flue gas recycle will determine how much of the remaining heat from the coal combustion will have to be removed. If the amount of flue gas recycle required by increasing solids recirculation and oxygen staging is limited, introducing the pure oxygen at multiple locations in the combustor to result in a more even temperature profile should result in a more compact system, thus reducing initial capital costs for construction. The overall efficiency of the process should be greater than that of an air-blown system since less fuel is required for the creation of the same amount of energy. The Energy & Environmental Research Center (EERC) is in a unique position to advance this technology. It has a world-class CFBC pilot plant, has experience with firing a wide range of fuels in our air-fired CFBC pilot plant, has prior experience with oxygen-firing a slagging furnace system in a pulverized coal-fired mode with a bituminous coal, and has all of the components required for oxygen-firing right next to the CFBC pilot plant already in place. An engineering study was performed to identify methods, an overall appropriate configuration, and an operating strategy for a fully oxygen-fired CFBC pilot plant by: (1) developing a plan to optimize

  5. SERI Aquatic Species Program: 1983 Annual Report

    SciTech Connect (OSTI)

    Not Available

    1984-03-01

    During 1983 research was carried out under three tasks: biological, engineering, and analysis. Biological research was aimed at screening for promising species of microalgae, macroalgae, and emergent plants that could be cultivated for energy products. Promising species were studied further to improve yields.

  6. Advanced engine management of individual cylinders for control of exhaust species

    DOE Patents [OSTI]

    Graves, Ronald L [Knoxville, TN; West, Brian H [Knoxville, TN; Huff, Shean P [Knoxville, TN; Parks, II, James E

    2008-12-30

    A method and system controls engine-out exhaust species of a combustion engine having a plurality of cylinders. The method typically includes various combinations of steps such as controlling combustion parameters in individual cylinders, grouping the individual cylinders into a lean set and a rich set of one or more cylinders, combusting the lean set in a lean combustion parameter condition having a lean air:fuel equivalence ratio, combusting the rich set in a rich combustion parameter condition having a rich air:fuel equivalence ratio, and adjusting the lean set and the rich set of one or more cylinders to generate net-lean combustion. The exhaust species may have elevated concentrations of hydrogen and oxygen.

  7. Controlled temperature expansion in oxygen production by molten alkali metal salts

    DOE Patents [OSTI]

    Erickson, Donald C.

    1985-06-04

    A continuous process is set forth for the production of oxygen from an oxygen containing gas stream, such as air, by contacting a feed gas stream with a molten solution of an oxygen acceptor to oxidize the acceptor and cyclically regenerating the oxidized acceptor by releasing oxygen from the acceptor wherein the oxygen-depleted gas stream from the contact zone is treated sequentially to temperature reduction by heat exchange against the feed stream so as to condense out entrained oxygen acceptor for recycle to the process, combustion of the gas stream with fuel to elevate its temperature and expansion of the combusted high temperature gas stream in a turbine to recover power.

  8. In Situ Bioreduction of Uranium (VI) to Submicromolar Levels and Reoxidation by Dissolved Oxygen

    SciTech Connect (OSTI)

    Wu, Weimin; Carley, Jack M; Luo, Jian; Ginder-Vogel, Matthew A.; Cardenas, Erick; Leigh, Mary Beth; Hwang, Chaichi; Kelly, Shelly D; Ruan, Chuanmin; Wu, Liyou; Van Nostrand, Joy; Gentry, Terry J; Lowe, Kenneth Alan; Mehlhorn, Tonia L; Carroll, Sue L; Luo, Wensui; Fields, Matthew Wayne; Gu, Baohua; Watson, David B; Kemner, Kenneth M; Marsh, Terence; Tiedje, James; Zhou, Jizhong; Fendorf, Scott; Kitanidis, Peter K.; Jardine, Philip M; Criddle, Craig

    2007-01-01

    Groundwater within Area 3 of the U.S. Department of Energy (DOE) Environmental Remediation Sciences Program (ERSP) Field Research Center at Oak Ridge, TN (ORFRC) contains up to 135 {micro}M uranium as U(VI). Through a series of experiments at a pilot scale test facility, we explored the lower limits of groundwater U(VI) that can be achieved by in-situ biostimulation and the effects of dissolved oxygen on immobilized uranium. Weekly 2 day additions of ethanol over a 2-year period stimulated growth of denitrifying, Fe(III)-reducing, and sulfate-reducing bacteria, and immobilization of uranium as U(IV), with dissolved uranium concentrations decreasing to low levels. Following sulfite addition to remove dissolved oxygen, aqueous U(VI) concentrations fell below the U.S. Environmental Protection Agency maximum contaminant limit (MCL) for drinking water (<30 {micro}g L{sup -1} or 0.126 {micro}M). Under anaerobic conditions, these low concentrations were stable, even in the absence of added ethanol. However, when sulfite additions stopped, and dissolved oxygen (4.0-5.5 mg L{sup -1}) entered the injection well, spatially variable changes in aqueous U(VI) occurred over a 60 day period, with concentrations increasing rapidly from <0.13 to 2.0 {micro}M at a multilevel sampling (MLS) well located close to the injection well, but changing little at an MLS well located further away. Resumption of ethanol addition restored reduction of Fe(III), sulfate, and U(VI) within 36 h. After 2 years of ethanol addition, X-ray absorption near-edge structure spectroscopy (XANES) analyses indicated that U(IV) comprised 60-80% of the total uranium in sediment samples. At the completion of the project (day 1260), U concentrations in MLS wells were less than 0.1 {micro}M. The microbial community at MLS wells with low U(VI) contained bacteria that are known to reduce uranium, including Desulfovibrio spp. and Geobacter spp., in both sediment and groundwater. The dominant Fe(III)-reducing species

  9. Formation of collisional sheath in electronegative plasma with two species of positive ions

    SciTech Connect (OSTI)

    Moulick, R. Goswami, K. S.

    2015-03-15

    Sheath formation is investigated for electronegative plasma in presence of two species of positive ions in collisional environment. The gas under consideration is a mixture of oxygen and argon. Argon is the considered as having fixed volume and impact of collision is studied with increasing pressure of oxygen. Fluid equations are solved for three species namely, the two positive ions and a negative ion. Electrons are considered to follow Boltzmann distribution. Collision is modeled by constant mean free path model and has been used as a parameter. It has been found that collision enhances the sheath formation. The negative ion core is nearly unaffected by the presence of collision and is governed by the electric potential. The negative flux field is, however, affected by the presence of collision and shows a steady behavior in front of the wall. The two positive ions are heavily affected by the presence of collision and the modeling is such that their equilibrium densities can be estimated by solving simultaneous cubic equations.

  10. Element- and charge-state-resolved ion energies in the cathodic arc plasma from composite AlCr cathodes in argon, nitrogen and oxygen atmospheres

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Franz, Robert; Polcik, Peter; Anders, André

    2015-06-01

    The energy distribution functions of ions in the cathodic arc plasma using composite AlCr cathodes were measured as a function of the background gas pressure in the range 0.5 to 3.5 Pa for different cathode compositions and gas atmospheres. The most abundant aluminium ions were Al+ regardless of the background gas species, whereas Cr2+ ions were dominating in Ar and N2 and Cr+ in O2 atmospheres. The energy distributions of the aluminium and chromium ions typically consisted of a high-energy fraction due to acceleration in the expanding plasma plume from the cathode spot and thermalised ions that were subjected tomore » collisions in the plasma cloud. The fraction of the latter increased with increasing background gas pressure. Atomic nitrogen and oxygen ions showed similar energy distributions as the aluminium and chromium ions, whereas the argon and molecular nitrogen and oxygen ions were formed at greater distance from the cathode spot and thus less subject to accelerating gradients. In addition to the positively charged metal and gas ions, negatively charged oxygen and oxygen-containing ions were observed in O2 atmosphere. The obtained results are intended to provide a comprehensive overview of the ion energies and charge states in the arc plasma of AlCr composite cathodes in different gas atmospheres as such plasmas are frequently used to deposit thin films and coatings.« less

  11. Element- and charge-state-resolved ion energies in the cathodic arc plasma from composite AlCr cathodes in argon, nitrogen and oxygen atmospheres

    SciTech Connect (OSTI)

    Franz, Robert; Polcik, Peter; Anders, Andr

    2015-06-01

    The energy distribution functions of ions in the cathodic arc plasma using composite AlCr cathodes were measured as a function of the background gas pressure in the range 0.5 to 3.5 Pa for different cathode compositions and gas atmospheres. The most abundant aluminium ions were Al+ regardless of the background gas species, whereas Cr2+ ions were dominating in Ar and N2 and Cr+ in O2 atmospheres. The energy distributions of the aluminium and chromium ions typically consisted of a high-energy fraction due to acceleration in the expanding plasma plume from the cathode spot and thermalised ions that were subjected to collisions in the plasma cloud. The fraction of the latter increased with increasing background gas pressure. Atomic nitrogen and oxygen ions showed similar energy distributions as the aluminium and chromium ions, whereas the argon and molecular nitrogen and oxygen ions were formed at greater distance from the cathode spot and thus less subject to accelerating gradients. In addition to the positively charged metal and gas ions, negatively charged oxygen and oxygen-containing ions were observed in O2 atmosphere. The obtained results are intended to provide a comprehensive overview of the ion energies and charge states in the arc plasma of AlCr composite cathodes in different gas atmospheres as such plasmas are frequently used to deposit thin films and coatings.

  12. Bimetallic Fe-Ni Oxygen Carriers for Chemical Looping Combustion

    SciTech Connect (OSTI)

    Bhavsar, Saurabh; Veser, Goetz

    2013-11-06

    The relative abundance, low cost, and low toxicity of iron make Fe-based oxygen carriers of great interest for chemical looping combustion (CLC), an emerging technology for clean and efficient combustion of fossil and renewable fuels. However, Fe also shows much lower reactivity than other metals (such as Ni and Cu). Here, we demonstrate strong improvement of Fe-based carriers by alloying the metal phase with Ni. Through a combination of carrier synthesis and characterization with thermogravimetric and fixed-bed reactor studies, we demonstrate that the addition of Ni results in a significant enhancement in activity as well as an increase in selectivity for total oxidation. Furthermore, comparing alumina and ceria as support materials highlights the fact that reducible supports can result in a strong increase in oxygen carrier utilization.

  13. Observing Oxygen Atoms Move during Information Storage in Tantalum Oxide

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Memristors | Stanford Synchrotron Radiation Lightsource Observing Oxygen Atoms Move during Information Storage in Tantalum Oxide Memristors Saturday, April 30, 2016 Memristor technology, or resistive random access memory (RRAM), is a frontrunner for next generation computer memory, owing to the promise of long endurance, low power, nanoscale device size and fast operation.1 Memristor devices are typically made of a transition metal oxide sandwiched between two metallic electrodes, and

  14. Excited states in the active media of oxygen - iodine lasers

    SciTech Connect (OSTI)

    Azyazov, V N

    2009-11-30

    A review of investigations of kinetic processes in active media oxygen - iodine lasers (OILs) performed in the last decade is presented. The mechanisms of pumping and quenching of electronically and vibrationally excited O{sub 2} and I{sub 2} molecules are considered, and dissociation mechanisms of I{sub 2} in the active medium of the OIL are analysed. The values of kinetic constants of processes proceeding in the active media of OILs are recommended. (review)

  15. Electrocatalyst for Oxygen Reduction with Reduced Platinum Oxidation and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dissolution Rates - Energy Innovation Portal Oxygen Reduction with Reduced Platinum Oxidation and Dissolution Rates Brookhaven National Laboratory Contact BNL About This Technology Publications: PDF Document Publication Electrodeposition of Pt onto RuO2 (110) Single-Crystal Surface (437 KB) <p> Results of a density functional theory calculation of atomic positions of platinum on an oxide surface, showing good agreement with experimental results.</p> Results of a density

  16. Ceramic Membranes for Hydrogen/Oxygen Production - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vehicles and Fuels Vehicles and Fuels Startup America Startup America Industrial Technologies Industrial Technologies Hydrogen and Fuel Cell Hydrogen and Fuel Cell Find More Like This Return to Search Ceramic Membranes for Hydrogen/Oxygen Production Ceramic Membranes Developed at Argonne May Bring Fuel-Cell Cars Closer to Reality Argonne National Laboratory Contact ANL About This Technology Technology Marketing Summary In the long term, hydrogen is expected to be the fuel of choice for both the

  17. Atomically Precise Electrocatalyst for Oxygen Evolution Reaction | Stanford

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Synchrotron Radiation Lightsource Atomically Precise Electrocatalyst for Oxygen Evolution Reaction Thursday, March 31, 2016 Traditional heterogeneous catalysts contain a range of particles sizes, crystallographic faces, and surface structures. This heterogeneity makes catalysts design a challenge because the active sites responsible for catalytic activity are simply not known. An emerging class of "atomically-precise" nanocatalysts can help alleviate this problem because they form

  18. Residual Oxygen on Nb Heated to 500 C

    SciTech Connect (OSTI)

    Kirby, R.; King, F.K.; Padamsee, H.; /Cornell U., LEPP

    2005-06-10

    The superconducting accelerating cavities for the International Linear Collider will be constructed of high-residual resistivity ratio (RRR) niobium sheet. Excessive oxygen within the skin depth (several microns) will reduce the RRR and increase resistive losses. We measure the thickness of this oxide layer, following bakeout simulation, to be about 0.5 nm thick. The results suggest that this layer will very slowly disappear from the top five nm at 500 C.

  19. Real Space Mapping of Oxygen Vacancy Diffusion and Electrochemical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transformations by Hysteretic Current Reversal Curve Measurements - Energy Innovation Portal Hydrogen and Fuel Cell Hydrogen and Fuel Cell Energy Storage Energy Storage Find More Like This Return to Search Real Space Mapping of Oxygen Vacancy Diffusion and Electrochemical Transformations by Hysteretic Current Reversal Curve Measurements Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryElectrochemical energy storage and conversion systems based on

  20. endangered species | OpenEI Community

    Open Energy Info (EERE)

    Contributor 4 September, 2012 - 21:36 Idaho Meeting 2 endangered species Fauna Fish and Wildlife Flora FWS Section 12 Section 7 The second Idaho GRR meeting was held today...

  1. OpenEI Community - endangered species

    Open Energy Info (EERE)

    http:en.openei.orgcommunityblogidaho-meeting-2comments endangered species Fauna Fish and Wildlife Flora FWS Section 12 Section 7 Wed, 05 Sep 2012 04:36:43 +0000 Kyoung 488...

  2. Aquatic Species Program (ASP): Lessons Learned

    SciTech Connect (OSTI)

    Jarvis, E. E.

    2008-02-01

    Presentation on lessons learned from the U.S. Department of Energy?s Aquatic Species Program 1978-1996 microalgae R&D activities, presented at the 2008 AFOSR Workshop in Washington, D.C.

  3. Growth control of oxygen stoichiometry in homoepitaxial SrTiO3...

    Office of Scientific and Technical Information (OSTI)

    Growth control of oxygen stoichiometry in homoepitaxial SrTiO3 films by pulsed laser epitaxy in high vacuum Prev Next Title: Growth control of oxygen stoichiometry in ...

  4. Selectivity of Chemisorbed Oxygen in C-H Bond Activation and...

    Office of Scientific and Technical Information (OSTI)

    Selectivity of Chemisorbed Oxygen in C-H Bond Activation and CO Oxidation and Kinetic ... Title: Selectivity of Chemisorbed Oxygen in C-H Bond Activation and CO Oxidation and ...

  5. SYSTEM DESIGN AND ANALYSIS FOR CONCEPTUAL DESIGN OF OXYGEN-BASED...

    Office of Scientific and Technical Information (OSTI)

    DESIGN OF OXYGEN-BASED PC BOILER Citation Details In-Document Search Title: SYSTEM DESIGN AND ANALYSIS FOR CONCEPTUAL DESIGN OF OXYGEN-BASED PC BOILER The objective of the system ...

  6. Impact of ethanol and butanol as oxygenates on SIDI engine efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ethanol and butanol as oxygenates on SIDI engine efficiency and emissions using steady-state and transient test procedures Impact of ethanol and butanol as oxygenates on SIDI engine ...

  7. Taguchi methods applied to oxygen-enriched diesel engine experiments

    SciTech Connect (OSTI)

    Marr, W.W.; Sekar, R.R.; Cole, R.L.; Marciniak, T.J.; Longman, D.E.

    1992-12-01

    This paper describes a test series conducted on a six-cylinder diesel engine to study the impacts of controlled factors (i.e., oxygen content of the combustion air, water content of the fuel, fuel rate, and fuel-injection timing) on engine emissions using Taguchi methods. Three levels of each factor were used in the tests. Only the main effects of the factors were examined; no attempt was made to analyze the interactions among the factors. It was found that, as in the case of the single-cylinder engine tests, oxygen in the combustion air was very effective in reducing particulate and smoke emissions. Increases in NO{sub x} due to the oxygen enrichment observed in the single-cylinder tests also occurred in the present six-cylinder tests. Water in the emulsified fuel was found to be much less effective in decreasing NO{sub x} emissions for the six-cylinder engine than it was for the single-cylinder engine.

  8. Taguchi methods applied to oxygen-enriched diesel engine experiments

    SciTech Connect (OSTI)

    Marr, W.W.; Sekar, R.R.; Cole, R.L.; Marciniak, T.J. ); Longman, D.E. )

    1992-01-01

    This paper describes a test series conducted on a six-cylinder diesel engine to study the impacts of controlled factors (i.e., oxygen content of the combustion air, water content of the fuel, fuel rate, and fuel-injection timing) on engine emissions using Taguchi methods. Three levels of each factor were used in the tests. Only the main effects of the factors were examined; no attempt was made to analyze the interactions among the factors. It was found that, as in the case of the single-cylinder engine tests, oxygen in the combustion air was very effective in reducing particulate and smoke emissions. Increases in NO[sub x] due to the oxygen enrichment observed in the single-cylinder tests also occurred in the present six-cylinder tests. Water in the emulsified fuel was found to be much less effective in decreasing NO[sub x] emissions for the six-cylinder engine than it was for the single-cylinder engine.

  9. Controllable positive exchange bias via redox-driven oxygen migration

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gilbert, Dustin A.; Olamit, Justin; Dumas, Randy K.; Kirby, B. J.; Grutter, Alexander J.; Maranville, Brian B.; Arenholz, Elke; Borchers, Julie A.; Liu, Kai

    2016-03-21

    We report that ionic transport in metal/oxide heterostructures offers a highly effective means to tailor material properties via modification of the interfacial characteristics. However, direct observation of ionic motion under buried interfaces and demonstration of its correlation with physical properties has been challenging. Using the strong oxygen affinity of gadolinium, we design a model system of GdxFe1-x/NiCoO bilayer films, where the oxygen migration is observed and manifested in a controlled positive exchange bias over a relatively small cooling field range. The exchange bias characteristics are shown to be the result of an interfacial layer of elemental nickel and cobalt, amore » few nanometres in thickness, whose moments are larger than expected from uncompensated NiCoO moments. This interface layer is attributed to a redox-driven oxygen migration from NiCoO to the gadolinium, during growth or soon after. Ultimately, these results demonstrate an effective path to tailoring the interfacial characteristics and interlayer exchange coupling in metal/oxide heterostructures.« less

  10. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Solicitations There is no open solicitation at this time. You can look for other federal assistance grants by visiting www.grants.gov off site link

    New Solicitations National Laser Users' Facility Grant Program New Solicitations There is no open solicitation at this time. You can look for other federal assistance grants by visiting www.grants.gov

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a

  11. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the Mexican Lake of Alchichica where massive carbonate rocks form. Cyanobacteria have been impacting the global carbon cycle of the Earth for more than 2.3 billion years by assimilating CO2 into organic compounds and triggering calcium carbonate (CaCO3) precipitation. Despite the importance of this cyanobacteria-mediated

  12. COMPUTATIONAL RESOURCES FOR BIOFUEL FEEDSTOCK SPECIES

    SciTech Connect (OSTI)

    Buell, Carol Robin; Childs, Kevin L

    2013-05-07

    While current production of ethanol as a biofuel relies on starch and sugar inputs, it is anticipated that sustainable production of ethanol for biofuel use will utilize lignocellulosic feedstocks. Candidate plant species to be used for lignocellulosic ethanol production include a large number of species within the Grass, Pine and Birch plant families. For these biofuel feedstock species, there are variable amounts of genome sequence resources available, ranging from complete genome sequences (e.g. sorghum, poplar) to transcriptome data sets (e.g. switchgrass, pine). These data sets are not only dispersed in location but also disparate in content. It will be essential to leverage and improve these genomic data sets for the improvement of biofuel feedstock production. The objectives of this project were to provide computational tools and resources for data-mining genome sequence/annotation and large-scale functional genomic datasets available for biofuel feedstock species. We have created a Bioenergy Feedstock Genomics Resource that provides a web-based portal or “clearing house” for genomic data for plant species relevant to biofuel feedstock production. Sequence data from a total of 54 plant species are included in the Bioenergy Feedstock Genomics Resource including model plant species that permit leveraging of knowledge across taxa to biofuel feedstock species.We have generated additional computational analyses of these data, including uniform annotation, to facilitate genomic approaches to improved biofuel feedstock production. These data have been centralized in the publicly available Bioenergy Feedstock Genomics Resource (http://bfgr.plantbiology.msu.edu/).

  13. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the Mexican Lake of Alchichica where massive carbonate rocks form. Cyanobacteria have been impacting the global carbon cycle of the Earth for more than 2.3 billion years by assimilating CO2 into organic compounds and triggering calcium carbonate (CaCO3) precipitation. Despite the importance of this cyanobacteria-mediated

  14. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the Mexican Lake of Alchichica where massive carbonate rocks form. Cyanobacteria have been impacting the global carbon cycle of the Earth for more than 2.3 billion years by assimilating CO2 into organic compounds and triggering calcium carbonate (CaCO3) precipitation. Despite the importance of this cyanobacteria-mediated

  15. New Species of Cyanobacteria Forms Intracellular Carbonates

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    New Species of Cyanobacteria Forms Intracellular Carbonates Print A new species of cyanobacteria-photosynthetic bacteria that occupy a wide array of habitats-was discovered in the Mexican Lake of Alchichica where massive carbonate rocks form. Cyanobacteria have been impacting the global carbon cycle of the Earth for more than 2.3 billion years by assimilating CO2 into organic compounds and triggering calcium carbonate (CaCO3) precipitation. Despite the importance of this cyanobacteria-mediated

  16. Solid Oxide Fuel Cell Cathodes. Unraveling the Relationship Between Structure, Surface Chemistry and Oxygen Reduction

    SciTech Connect (OSTI)

    Gopalan, Srikanth

    2013-03-31

    In this work we have considered oxygen reduction reaction on LSM and LSCF cathode materials. In particular we have used various spectroscopic techniques to explore the surface composition, transition metal oxidation state, and the bonding environment of oxygen to understand the changes that occur to the surface during the oxygen reduction process. In a parallel study we have employed patterned cathodes of both LSM and LSCF cathodes to extract transport and kinetic parameters associated with the oxygen reduction process.

  17. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOE Patents [OSTI]

    Cassano, Anthony A.

    1985-01-01

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs.

  18. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOE Patents [OSTI]

    Cassano, A.A.

    1985-07-02

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs. 3 figs.

  19. Method and apparatus for producing oxygen and nitrogen and membrane therefor

    DOE Patents [OSTI]

    Roman, Ian C.; Baker, Richard W.

    1985-01-01

    Process and apparatus for the separation and purification of oxygen and nitrogen as well as a novel membrane useful therein are disclosed. The process utilizes novel facilitated transport membranes to selectively transport oxygen from one gaseous stream to another, leaving nitrogen as a byproduct. In the method, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a polar organic membrane which separates a gaseous feed stream such as atmospheric air and a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. In an alternate mode of operation, the feed stream is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane and the product stream is maintained at a sufficiently high temperature to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. Under such conditions, the carrier acts as a shuttle, picking up oxygen at the feed side of the membrane, diffusing across the membrane as the oxygenated complex, releasing oxygen to the product stream, and then diffusing back to the feed side to repeat the process. Exceptionally and unexpectedly high O.sub.2 /N.sub.2 selectivity, on the order of 10 to 30, is obtained, as well as exceptionally high oxygen permeability, on the order of 6 to 15.times.10.sup.-8 cm.sup.3 -cm/cm.sup.2 -sec-cmHg, as well as a long membrane life of in excess of 3 months, making the process commercially feasible.

  20. Method and apparatus for producing oxygen and nitrogen and membrane therefor

    DOE Patents [OSTI]

    Roman, I.C.; Baker, R.W.

    1985-09-17

    Process and apparatus for the separation and purification of oxygen and nitrogen as well as a novel membrane useful therein are disclosed. The process utilizes novel facilitated transport membranes to selectively transport oxygen from one gaseous stream to another, leaving nitrogen as a byproduct. In the method, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a polar organic membrane which separates a gaseous feed stream such as atmospheric air and a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. In an alternate mode of operation, the feed stream is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane and the product stream is maintained at a sufficiently high temperature to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. Under such conditions, the carrier acts as a shuttle, picking up oxygen at the feed side of the membrane, diffusing across the membrane as the oxygenated complex, releasing oxygen to the product stream, and then diffusing back to the feed side to repeat the process. Exceptionally and unexpectedly high O[sub 2]/N[sub 2] selectivity, on the order of 10 to 30, is obtained, as well as exceptionally high oxygen permeability, on the order of 6 to 15 [times] 10[sup [minus]8] cm[sup 3]-cm/cm[sup 2]-sec-cmHg, as well as a long membrane life of in excess of 3 months, making the process commercially feasible. 2 figs.

  1. Disappearance of oxygen in concrete under irradiation: The role of peroxides in radiolysis

    SciTech Connect (OSTI)

    Bouniol, P.; Aspart, A.

    1998-11-01

    Under irradiation, the interstitial liquid in concretes is affected by radiolysis. Normally produced with H{sub 2} in alkaline medium, O{sub 2} is not observed. It is shown that the disappearance of O{sub 2} results not only from the fast reaction with the e{sub aq}{sup {minus}} radical, which causes a negative redox potential, but also from peroxide trapping in CaO{sub 2}{center_dot}8H{sub 2}O, a highly insoluble phase whose solubility product is estimated at 2.8 {times} 10{sup {minus}11}. The disequilibrium that occurs in the redox sequence dioxygen (0) {leftrightarrow} superoxide ({minus}{1/2}) {leftrightarrow} peroxide ({minus}1) is responsible for depleting most of the oxygenated species in the solution. CaO{sub 2}{center_dot}8H{sub 2}O is formed at the expense of calcium in solution, of portlandite, and of ettringite, but, being unstable, it disappears in the cement paste when H{sub 2}OI{sub 2} is no longer present in the medium. Consideration of the reaction between Ca(OH){sub 2} and H{sub 2}O{sub 2} in the CHEMSIMUL kinetic code, which also highlights O{sub 2} consumption, seems to describe the long-term radiolysis of concrete accurately.

  2. Species interactions differ in their genetic robustness

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chubiz, Lon M.; Granger, Brian R.; Segre, Daniel; Harcombe, William R.

    2015-04-14

    Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species' interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S.more » enterica. The type of interaction between species was set by modulating the initial metabolites present in the environment. We found that the community was most robust to genetic perturbations when the organisms were cooperating. Species ratios were more stable in the cooperative community, and community biomass had equal variance in the two contexts. Additionally, the number of mutations that have a substantial effect is lower when the species cooperate than when they are competing. In contrast, when mutations were added to the S. enterica network the system was more robust when the bacteria were competing. These results highlight the utility of connecting metabolic mechanisms and studies of ecological stability. Cooperation and conflict alter the connection between genetic changes and properties that emerge at higher levels of biological organization.« less

  3. Lattice Distortions and Oxygen Vacancies Produced in Au+-Irradiated Nanocrystalline Cubic Zirconia

    SciTech Connect (OSTI)

    Edmondson, P. D.; Weber, William J.; Namavar, Fereydoon; Zhang, Yanwen

    2011-07-13

    The oxygen ion conductivity, attributed to an oxygen vacancy mechanism, of yttria-stabilized zirconia membranes used in solid oxide fuel cells is restricted due to trapping limitations. In this work, a high concentration of oxygen vacancies has been deliberately introduced into nanocrystalline stabilizer-free zirconia through ion-irradiation. Oxygen vacancies with different charge states can be produced by varying irradiation temperatures. Due to the reduced trapping sites and high oxygen vacancy concentration, this work suggests that the efficiency of solid oxide fuel cells can be improved.

  4. Oxygen transport in off-stoichiometric uranium dioxide mediated by defect clustering dynamics

    SciTech Connect (OSTI)

    Yu, Jianguo Bai, Xian-Ming; El-Azab, Anter; Allen, Todd R.

    2015-03-07

    Oxygen transport is central to many properties of oxides such as stoichiometric changes, phase transformation, and ionic conductivity. In this paper, we report a mechanism for oxygen transport in uranium dioxide (UO{sub 2}) in which the kinetics is mediated by defect clustering dynamics. In particular, the kinetic Monte Carlo method has been used to investigate the kinetics of oxygen transport in UO{sub 2} under the condition of creation and annihilation of oxygen vacancies and interstitials as well as oxygen interstitial clustering, with variable off-stoichiometry and temperature conditions. It is found that in hypo-stoichiometric UO{sub 2?x}, oxygen transport is well described by the vacancy diffusion mechanism while in hyper-stoichiometric UO{sub 2+x}, oxygen interstitial cluster diffusion contributes significantly to oxygen transport kinetics, particularly at high temperatures and high off-stoichiometry levels. It is also found that di-interstitial clusters and single interstitials play dominant roles in oxygen diffusion while other larger clusters have negligible contributions. However, the formation, coalescence, and dissociation of these larger clusters indirectly affects the overall oxygen diffusion due to their interactions with mono and di-interstitials, thus providing an explanation of the experimental observation of saturation or even drop of oxygen diffusivity at high off-stoichiometry.

  5. Oxygen transport in off-stoichiometric uranium dioxide mediated by defect clustering dynamics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, Jianguo; Bai, Xian -Ming; El-Azab, Anter; Allen, Todd R.

    2015-03-05

    In this study, oxygen transport is central to many properties of oxides such as stoichiometric changes, phase transformation and ionic conductivity. In this paper, we report a mechanism for oxygen transport in uranium dioxide (UO2) in which the kinetics is mediated by defect clustering dynamics. In particular, the kinetic Monte Carlo (KMC) method has been used to investigate the kinetics of oxygen transport in UO2 under the condition of creation and annihilation of oxygen vacancies and interstitials as well as oxygen interstitial clustering, with variable offstoichiometry and temperature conditions. It is found that in hypo-stoichiometric UO2-x, oxygen transport is wellmore » described by the vacancy diffusion mechanism while in hyper-stoichiometric UO2+x, oxygen interstitial cluster diffusion contributes significantly to oxygen transport kinetics, particularly at high temperatures and high off-stoichiometry levels. It is also found that diinterstitial clusters and single interstitials play dominant roles in oxygen diffusion while other larger clusters have negligible contributions. However, the formation, coalescence and dissociation of these larger clusters indirectly affects the overall oxygen diffusion due to their interactions with mono and di-interstitials, thus providing a explanation of the experimental observation of saturation or even drop of oxygen diffusivity at high off-stoichiometry.« less

  6. Oxygen transport in off-stoichiometric uranium dioxide mediated by defect clustering dynamics

    SciTech Connect (OSTI)

    Yu, Jianguo; Bai, Xian -Ming; El-Azab, Anter; Allen, Todd R.

    2015-03-05

    In this study, oxygen transport is central to many properties of oxides such as stoichiometric changes, phase transformation and ionic conductivity. In this paper, we report a mechanism for oxygen transport in uranium dioxide (UO2) in which the kinetics is mediated by defect clustering dynamics. In particular, the kinetic Monte Carlo (KMC) method has been used to investigate the kinetics of oxygen transport in UO2 under the condition of creation and annihilation of oxygen vacancies and interstitials as well as oxygen interstitial clustering, with variable offstoichiometry and temperature conditions. It is found that in hypo-stoichiometric UO2-x, oxygen transport is well described by the vacancy diffusion mechanism while in hyper-stoichiometric UO2+x, oxygen interstitial cluster diffusion contributes significantly to oxygen transport kinetics, particularly at high temperatures and high off-stoichiometry levels. It is also found that diinterstitial clusters and single interstitials play dominant roles in oxygen diffusion while other larger clusters have negligible contributions. However, the formation, coalescence and dissociation of these larger clusters indirectly affects the overall oxygen diffusion due to their interactions with mono and di-interstitials, thus providing a explanation of the experimental observation of saturation or even drop of oxygen diffusivity at high off-stoichiometry.

  7. Oxygen vacancy ordering within anion-deficient Ceria

    SciTech Connect (OSTI)

    Hull, S.; Norberg, S.T.; Ahmed, I.; Eriksson, S.G.; Marrocchelli, D.; Madden, P.A.

    2009-10-15

    The structural properties of anion deficient ceria, CeO{sub 2-{delta}}, have been studied as a function of oxygen partial pressure, p(O{sub 2}), over the range 0>=log{sub 10p}(O{sub 2})>=-18.9 at 1273(2) K using the neutron powder diffraction technique. Rietveld refinement of the diffraction data collected on decreasing p(O{sub 2}) showed increases in the cubic lattice parameter, a, the oxygen nonstoichiometry, delta, and the isotropic thermal vibration parameters, u{sub Ce} and u{sub O}, starting at log{sub 10p}(O{sub 2}){approx}-11. The increases are continuous, but show a distinct kink at log{sub 10p}(O{sub 2}){approx}-14.5. Analysis of the total scattering (Bragg plus diffuse components) using reverse Monte Carlo (RMC) modelling indicates that the O{sup 2-} vacancies preferentially align as pairs in the <111> cubic directions as the degree of nonstoichiometry increases. This behaviour is discussed with reference to the chemical crystallography of the CeO{sub 2}-Ce{sub 2}O{sub 3} system at ambient temperature and, in particular, to the nature of the long-range ordering of O{sup 2-} vacancies within the crystal structure of Ce{sub 7}O{sub 12}. - Graphical abstract: Partial radial distribution function for oxygen vacancies within CeO{sub 1.710} at 1273 K (solid line) showing the increased tendency for local ordering in <111> directions compared to a random distribution (dashed line).

  8. Oxygen transport membrane system and method for transferring heat to catalytic/process reactors

    DOE Patents [OSTI]

    Kelly, Sean M; Kromer, Brian R; Litwin, Michael M; Rosen, Lee J; Christie, Gervase Maxwell; Wilson, Jamie R; Kosowski, Lawrence W; Robinson, Charles

    2014-01-07

    A method and apparatus for producing heat used in a synthesis gas production is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the stream reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

  9. Oxygen transport membrane system and method for transferring heat to catalytic/process reactors

    DOE Patents [OSTI]

    Kelly, Sean M.; Kromer, Brian R.; Litwin, Michael M.; Rosen, Lee J.; Christie, Gervase Maxwell; Wilson, Jamie R.; Kosowski, Lawrence W.; Robinson, Charles

    2016-01-19

    A method and apparatus for producing heat used in a synthesis gas production process is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the steam reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5

  10. In-Cylinder Reaction Chemistry and Kinetics During Negative Valve Overlap Fuel Injection Under Low-Oxygen Conditions

    SciTech Connect (OSTI)

    Kalaskar, Vickey B; Szybist, James P; Splitter, Derek A; Pihl, Josh A; Gao, Zhiming; Daw, C Stuart

    2013-01-01

    Fuel injection into the negative valve overlap (NVO) period is a common method for controlling combustion phasing in homogeneous charge compression ignition (HCCI) as well as other forms of advanced combustion. During this event, at least a portion of the fuel hydrocarbons can be converted to products containing significant levels of H2 and CO, as well as other short chain hydrocarbons by means of thermal cracking, water-gas shift, and partial oxidation reactions, depending on the availability of oxygen and the time-temperature-pressure history. The resulting products alter the autoignition properties of the combined fuel mixture for HCCI. Fuel-rich chemistry in a partial oxidation environment is also relevant to other high efficiency engine concepts (e.g., the dedicated EGR (D-EGR) concept from SWRI). In this study, we used a unique 6-stroke engine cycle to experimentally investigate the chemistry of a range of fuels injected during NVO under low oxygen conditions. Fuels investigated included iso-octane, iso-butanol, ethanol, and methanol. Products from NVO chemistry were highly dependent on fuel type and injection timing, with iso-octane producing less than 1.5% hydrogen and methanol producing more than 8%. We compare the experimental trends with CHEMKIN (single zone, 0-D model) predictions using multiple kinetic mechanisms available in the current literature. Our primary conclusion is that the kinetic mechanisms investigated are unable to accurately predict the magnitude and trends of major species we observed.

  11. Computational fluid dynamics analysis of a wire-feed, high-velocity oxygen-fuel (HVOF) thermal spray torch

    SciTech Connect (OSTI)

    Lopez, A.R.; Hassan, B.; Oberkampf, W.L.; Neiser, R.A.; Roemer, T.J.

    1996-09-01

    The fluid and particle dynamics of a High-Velocity Oxygen-Fuel Thermal Spray torch are analyzed using computational and experimental techniques. Three-dimensional Computational Fluid Dynamics (CFD) results are presented for a curved aircap used for coating interior surfaces such as engine cylinder bores. The device analyzed is similar to the Metco Diamond Jet Rotating Wire (DJRW) torch. The feed gases are injected through an axisymmetric nozzle into the curved aircap. Premixed propylene and oxygen are introduced from an annulus in the nozzle, while cooling air is injected between the nozzle and the interior wall of the aircap. The combustion process is modeled using a single-step finite-rate chemistry model with a total of 9 gas species which includes dissociation of combustion products. A continually-fed steel wire passes through the center of the nozzle and melting occurs at a conical tip near the exit of the aircap. Wire melting is simulated computationally by injecting liquid steel particles into the flow field near the tip of the wire. Experimental particle velocity measurements during wire feed were also taken using a Laser Two-Focus (L2F) velocimeter system. Flow fields inside and outside the aircap are presented and particle velocity predictions are compared with experimental measurements outside of the aircap.

  12. Method for providing oxygen ion vacancies in lanthanide oxides

    DOE Patents [OSTI]

    Kay, D. Alan R.; Wilson, William G.

    1989-12-05

    A method for desulfurization of fuel gases resulting from the incomplete combustion of sulfur containing hydrocarbons whereby the gases are treated with lanthanide oxides containing large numbers of oxygen-ion vacancies providing ionic porosity which enhances the ability of the lanthanide oxides to react more rapidly and completely with the sulfur in the fuel gases whereby the sulfur in such gases is reduced to low levels suitable for fuels for firing into boilers of power plants generating electricity with steam turbine driven generators, gas turbines, fuel cells and precursors for liquid fuels such as methanol and the like.

  13. Oxygen-stabilized zirconium-vanadium intermetallic compound

    DOE Patents [OSTI]

    Mendelsohn, M.H.; Gruen, D.M.

    1981-10-06

    An oxygen stabilized intermetallic compound having the formula Zr/sub x/OV/sub y/ where x = 0.7 to 2.0 and y = 0.18 to 0.33 is described. The compound is capable of reversibly sorbing hydrogen at temperatures from - 196/sup 0/C to 450/sup 0/C at pressures down to 10/sup -6/ Torr. The compound is also capable of selectively sorbing hydrogen from gaseous mixtures in the presence of CO and CO/sub 2/.

  14. Thermochemical generation of hydrogen and oxygen from water

    DOE Patents [OSTI]

    Robinson, Paul R.; Bamberger, Carlos E.

    1982-01-01

    A thermochemical cyclic process for the production of hydrogen exploits the reaction between sodium manganate (NaMnO.sub.2) and titanium dioxide (TiO.sub.2) to form sodium titanate (Na.sub.2 TiO.sub.3), manganese (II) titanate (MnTiO.sub.3) and oxygen. The titanate mixture is treated with sodium hydroxide, in the presence of steam, to form sodium titanate, sodium manganate (III), water and hydrogen. The sodium titanate-manganate (III) mixture is treated with water to form sodium manganate (III), titanium dioxide and sodium hydroxide. Sodium manganate (III) and titanium dioxide are recycled following dissolution of sodium hydroxide in water.

  15. Thermochemical generation of hydrogen and oxygen from water

    DOE Patents [OSTI]

    Robinson, Paul R.; Bamberger, Carlos E.

    1981-01-01

    A thermochemical cyclic process for the production of hydrogen exploits the reaction between sodium manganate (NaMnO.sub.2) and titanium dioxide (TiO.sub.2) to form sodium titanate (Na.sub.2 TiO.sub.3), manganese (II) titanate (MnTiO.sub.3) and oxygen. The titanate mixture is treated with sodium hydroxide, in the presence of steam, to form sodium titanate, sodium manganate (III), water and hydrogen. The sodium titanate-manganate (III) mixture is treated with water to form sodium manganate (III), titanium dioxide and sodium hydroxide. Sodium manganate (III) and titanium dioxide are recycled following dissolution of sodium hydroxide in water.

  16. Recent advances in the kinetics of oxygen reduction

    SciTech Connect (OSTI)

    Adzic, R.

    1996-07-01

    Oxygen reduction is considered an important electrocatalytic reaction; the most notable need remains improvement of the catalytic activity of existing metal electrocatalysts and development of new ones. A review is given of new advances in the understanding of reaction kinetics and improvements of the electrocatalytic properties of some surfaces, with focus on recent studies of relationship of the surface properties to its activity and reaction kinetics. The urgent need is to improve catalytic activity of Pt and synthesize new, possibly non- noble metal catalysts. New experimental techniques for obtaining new level of information include various {ital in situ} spectroscopies and scanning probes, some involving synchrotron radiation. 138 refs, 18 figs, 2 tabs.

  17. Hydrogen and oxygen concentrations in IXCs: A compilation

    SciTech Connect (OSTI)

    Liljegren, L.M.; Terrones, G.T.; Melethil, P.K.

    1996-06-01

    This paper contains four reports and two internal letters that address the estimation of hydrogen and oxygen concentrations in ion exchange columns that treat the water of the K-East and K-West Basins at Hanford. The concern is the flammability of this mixture of gases and planning for safe transport during decommissioning. A transient will occur when the hydrogen filter is temporarily blocked by a sandbag. Analyses are provided for steady-state, transients, and for both wet and dry resins.

  18. Electrode Interface Dictates Oxygen Evolution from Lithium Peroxide in

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Li-O2 Batteries - Joint Center for Energy Storage Research December 16, 2014, Research Highlights Electrode Interface Dictates Oxygen Evolution from Lithium Peroxide in Li-O2 Batteries Isolation of the charge reaction from the discharge in Li-O2 cells by utilizing electrodes prefilled with commercial lithium peroxide provides a unique method to understand interfacial properties. OER is very facile on TiC, which lacks a significant oxide film and occurs at a much lower overpotential relative

  19. Device for measuring oxygen activity in liquid sodium

    DOE Patents [OSTI]

    Roy, P.; Young, R.S.

    1973-12-01

    A composite ceramic electrolyte in a configuration (such as a closed end tube or a plate) suitable to separate liquid sodium from a reference electrode with a high impedance voltmeter connected to measure EMF between the sodium and the reference electrode as a measure of oxygen activity in the sodium is described. The composite electrolyte consists of zirconiacalcia with a bonded layer of thoria-yttria. The device is used with a gaseous reference electrode on the zirconia-calcia side and liquid sodium on the thoria-yttria side of the electrolyte. (Official Gazette)

  20. Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control

    SciTech Connect (OSTI)

    Nsakala ya Nsakala; Gregory N. Liljedahl; David G. Turek

    2007-03-31

    Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic (i.e., man-made) CO{sub 2} emissions. In 2001, ALSTOM Power Inc. (ALSTOM) began a two-phase program to investigate the feasibility of various carbon capture technologies. This program was sponsored under a Cooperative Agreement from the US Department of Energy's National Energy Technology Laboratory (DOE). The first phase entailed a comprehensive study evaluating the technical feasibility and economics of alternate CO{sub 2} capture technologies applied to Greenfield US coal-fired electric generation power plants. Thirteen cases, representing various levels of technology development, were evaluated. Seven cases represented coal combustion in CFB type equipment. Four cases represented Integrated Gasification Combined Cycle (IGCC) systems. Two cases represented advanced Chemical Looping Combined Cycle systems. Marion, et al. reported the details of this work in 2003. One of the thirteen cases studied utilized an oxygen-fired circulating fluidized bed (CFB) boiler. In this concept, the fuel is fired with a mixture of oxygen and recirculated flue gas (mainly CO{sub 2}). This combustion process yields a flue gas containing over 80 percent (by volume) CO{sub 2}. This flue gas can be processed relatively easily to enrich the CO{sub 2} content to over 96 percent for use in enhanced oil or gas recovery (EOR or EGR) or simply dried for sequestration. The Phase I study identified the O{sub 2}-fired CFB as having a near term development potential, because it uses conventional commercial CFB technology and commercially available CO{sub 2} capture enabling technologies such as cryogenic air separation and simple rectification or distillation gas processing systems. In the long term, air separation technology

  1. Candidate and Special Status Species | Open Energy Information

    Open Energy Info (EERE)

    Status Species Jump to: navigation, search Retrieved from "http:en.openei.orgwindex.php?titleCandidateandSpecialStatusSpecies&oldid612384" Feedback Contact needs...

  2. USFWS Endangered Species Act and Section 7 Regulations and Resources

    Office of Energy Efficiency and Renewable Energy (EERE)

    The purpose of the Endangered Species Act (ESA) is to protect and recover imperiled species and the ecosystems upon which they depend.

  3. Fluorophore-based sensor for oxygen radicals in processing plasmas

    SciTech Connect (OSTI)

    Choudhury, Faraz A.; Shohet, J. Leon; Sabat, Grzegorz; Sussman, Michael R.; Nishi, Yoshio

    2015-11-15

    A high concentration of radicals is present in many processing plasmas, which affects the processing conditions and the properties of materials exposed to the plasma. Determining the types and concentrations of free radicals present in the plasma is critical in order to determine their effects on the materials being processed. Current methods for detecting free radicals in a plasma require multiple expensive and bulky instruments, complex setups, and often, modifications to the plasma reactor. This work presents a simple technique that detects reactive-oxygen radicals incident on a surface from a plasma. The measurements are made using a fluorophore dye that is commonly used in biological and cellular systems for assay labeling in liquids. Using fluorometric analysis, it was found that the fluorophore reacts with oxygen radicals incident from the plasma, which is indicated by degradation of its fluorescence. As plasma power was increased, the quenching of the fluorescence significantly increased. Both immobilized and nonimmobilized fluorophore dyes were used and the results indicate that both states function effectively under vacuum conditions. The reaction mechanism is very similar to that of the liquid dye.

  4. Nickel-hydrogen battery with oxygen and electrolyte management features

    DOE Patents [OSTI]

    Sindorf, John F.

    1991-10-22

    A nickel-hydrogen battery or cell having one or more pressure vessels containing hydrogen gas and a plurality of cell-modules therein. Each cell-module includes a configuration of cooperatively associated oxygen and electrolyte mangement and component alignment features. A cell-module having electrolyte includes a negative electrode, a positive electrode adapted to facilitate oxygen diffusion, a separator disposed between the positive and negative electrodes for separating them and holding electrolyte for ionic conductivity, an absorber engaging the surface of the positive electrode facing away from the separator for providing electrolyte to the positive electrode, and a pair of surface-channeled diffusion screens for enclosing the positive and negative electrodes, absorber, and separator and for maintaining proper alignment of these components. The screens, formed in the shape of a pocket by intermittently sealing the edges together along as many as three sides, permit hydrogen gas to diffuse therethrough to the negative electrodes, and prevent the edges of the separator from swelling. Electrolyte is contained in the cell-module, absorbhed by the electrodes, the separator and the absorber.

  5. Oxygen transport properties estimation by DSMC-CT simulations

    SciTech Connect (OSTI)

    Bruno, Domenico; Frezzotti, Aldo; Ghiroldi, Gian Pietro

    2014-12-09

    Coupling DSMC simulations with classical trajectories calculations is emerging as a powerful tool to improve predictive capabilities of computational rarefied gas dynamics. The considerable increase of computational effort outlined in the early application of the method (Koura,1997) can be compensated by running simulations on massively parallel computers. In particular, GPU acceleration has been found quite effective in reducing computing time (Ferrigni,2012; Norman et al.,2013) of DSMC-CT simulations. The aim of the present work is to study rarefied Oxygen flows by modeling binary collisions through an accurate potential energy surface, obtained by molecular beams scattering (Aquilanti, et al.,1999). The accuracy of the method is assessed by calculating molecular Oxygen shear viscosity and heat conductivity following three different DSMC-CT simulation methods. In the first one, transport properties are obtained from DSMC-CT simulations of spontaneous fluctuation of an equilibrium state (Bruno et al, Phys. Fluids, 23, 093104, 2011). In the second method, the collision trajectory calculation is incorporated in a Monte Carlo integration procedure to evaluate the Taxman’s expressions for the transport properties of polyatomic gases (Taxman,1959). In the third, non-equilibrium zero and one-dimensional rarefied gas dynamic simulations are adopted and the transport properties are computed from the non-equilibrium fluxes of momentum and energy. The three methods provide close values of the transport properties, their estimated statistical error not exceeding 3%. The experimental values are slightly underestimated, the percentage deviation being, again, few percent.

  6. Radiation chemistry of alternative fuel oxygenates -- Substituted ethers

    SciTech Connect (OSTI)

    Mezyk, S. P.; Cooper, W. J.; Bartels, D. M.; Tobien, T.; O'Shea, K. E.

    1999-11-15

    The electron beam process, an advanced oxidation and reduction technology, is based in the field of radiation chemistry. Fundamental to the development of treatment processes is an understanding of the underlying chemistry. The authors have previously evaluated the bimolecular rate constants for the reactions of methyl tert-butyl ether (MTBE) and with this study have extended their studies to include ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE) and tert-amyl methyl ether (TAME) with the hydroxyl radical, hydrogen atom and solvated electron using pulse radiolysis. For all of the oxygenates the reaction with the hydroxyl radical appears to be of primary interest in the destruction of the compounds in water. The rates with the solvated electron are limiting values as the rates appear to be relatively low. The hydrogen atom rate constants are relatively low, coupled with the low yield in radiolysis, they concluded that these are of little significance in the destruction of the alternative fuel oxygenates (and MTBE).

  7. Imaging Hindered Rotations of Alkoxy Species on TiO2(110)

    SciTech Connect (OSTI)

    Zhang, Zhenrong; Rousseau, Roger J.; Gong, Jinlong; Kay, Bruce D.; Dohnalek, Zdenek

    2009-12-16

    We present the first study of the rotational dynamics of organic species on any oxide surface. Specifically, variable-temperature scanning tunneling microscopy (STM) and dispersion-corrected density functional theory are used to study the alkyl chain conformational disorder and dynamics of 1-, 2-, 3- and 4-octoxy on rutile TiO2(110). Initially, the geminate pairs of the octoxy and bridging hydroxyl species are created via octanol dissociation on bridging-oxygen (Ob) vacancy defects. The STM images provide time averaged snapshots of octoxy species rotating among multiple energetically nearly-degenerate configurations accessible at a given temperature. In the calculations we find that the underlying corrugated potential energy surface is a result of the interplay between attractive Van der Waals dispersion forces leading to weak attractive C...Ti and repulsive C...Ob interactions which lead to large barriers of 50-70kJmol-1 for the rotation of the octoxy alkyl chains across the Ob rows. In the presence of the germinal hydroxyl groups we find that the relative populations of the various conformations as well as the rotational barriers are perturbed by the presence of geminate hydroxyl due to additional C...hydroxyl repulsions.

  8. Mechanisms of pyrite oxidation to non-slagging species. Quarterly report, October 1--December 31, 1996

    SciTech Connect (OSTI)

    Akan-Etuk, A.E.J.; Mitchell, R.E.

    1997-12-31

    This document is the tenth quarterly status report on a project that is concerned with enhancing the transformation of iron pyrite to non-slagging species during staged, low-NO{sub x} pulverized coal (P.C.) combustion. The research project is intended to advance PETC`s efforts to improve the technical understanding of the high-temperature chemical and physical processes involved in the utilization of coal. The work focuses on the mechanistic description and rate quantification of the effects of fuel properties and combustion environment on the oxidation of iron pyrite to form the non-slagging species magnetite. During this report period numerical encoding of a pyrite combustion model was embarked upon. The effort was intended to lead to predictive capabilities with respect to pyrite composition during pulverized coal firing. Many subroutines were written of a FORTRAN computer program to track the fate of a pyrite particle by integrating time-dependent differential equations for species, momentum, and energy conservation. Inputs to the program include fuel-related properties such as particle size and composition, as well as properties of the reactor environment such as oxygen level, temperature, gas velocity, and a set of initial and final positions.

  9. Species interactions differ in their genetic robustness

    SciTech Connect (OSTI)

    Chubiz, Lon M.; Granger, Brian R.; Segre, Daniel; Harcombe, William R.

    2015-04-14

    Conflict and cooperation between bacterial species drive the composition and function of microbial communities. Stability of these emergent properties will be influenced by the degree to which species' interactions are robust to genetic perturbations. We use genome-scale metabolic modeling to computationally analyze the impact of genetic changes when Escherichia coli and Salmonella enterica compete, or cooperate. We systematically knocked out in silico each reaction in the metabolic network of E. coli to construct all 2583 mutant stoichiometric models. Then, using a recently developed multi-scale computational framework, we simulated the growth of each mutant E. coli in the presence of S. enterica. The type of interaction between species was set by modulating the initial metabolites present in the environment. We found that the community was most robust to genetic perturbations when the organisms were cooperating. Species ratios were more stable in the cooperative community, and community biomass had equal variance in the two contexts. Additionally, the number of mutations that have a substantial effect is lower when the species cooperate than when they are competing. In contrast, when mutations were added to the S. enterica network the system was more robust when the bacteria were competing. These results highlight the utility of connecting metabolic mechanisms and studies of ecological stability. Cooperation and conflict alter the connection between genetic changes and properties that emerge at higher levels of biological organization.

  10. Identification of combustion intermediates in a low-pressure premixed laminar 2,5-dimethylfuran/oxygen/argon flame with tunable synchrotron photoionization

    SciTech Connect (OSTI)

    Wu, Xuesong; Huang, Zuohua; Wei, Lixia [State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049 (China); Yuan, Tao; Zhang, Kuiwen [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

    2009-07-15

    Low-pressure (4.0 kPa) premixed laminar 2,5-dimethylfuran (DMF)/oxygen/argon flame with an equivalence ratio of 2.0 was studied with tunable vacuum ultraviolet (VUV) synchrotron radiation photoionization and molecular-beam mass spectrometry. Photoionization mass spectra of DMF/O{sub 2}/Ar flame were recorded and the photoionization efficiency curves of the combustion intermediates were measured. Flame species, including isomeric intermediates, are identified by comparing the measured ionization energies with those reported in literatures or those calculated with Gaussian-3 procedure. More than 70 species have been detected, including furan and its derivatives, aromatics, and free radicals. Possible reaction pathways of DMF, 2-methylfuran, and furan are proposed based on the intermediates identified. DMF can be consumed by H-abstraction and pyrolysis reactions. 2-Methylfuran and furan can be consumed by H-abstraction, H-addition and pyrolysis reactions. (author)

  11. Conceptual Design of Oxygen-Based PC Boiler

    SciTech Connect (OSTI)

    Andrew Seltzer; Zhen Fan

    2005-09-01

    Coal is presently the world's primary fuel for generating electrical power and, being more abundant and less expensive than oil or natural gas, is expected to continue its dominance into the future. Coal, however, is more carbon intensive than natural gas and oil and consequently coal-fired power plants are large point source emitters of carbon dioxide (CO{sub 2}). Since CO{sub 2} is a greenhouse gas, which may have an adverse impact on the world's climate/weather patterns, studies have been conducted to determine the feasibility and economic impact of capturing power plant CO{sub 2} emissions for pipeline transport to a sequestration/storage site. The stack gas that exhausts from a modern coal-fired power plant typically contains about 15% CO{sub 2} on a dry volume basis. Although there are numerous processes available for removing CO{sub 2} from gas streams, gas scrubbing with amine solvent is best suited for this application because of the large gas volumes and low CO{sub 2} concentrations involved. Unfortunately the energy required to regenerate the solvent for continued use as a capturing agent is large and imposes a severe energy penalty on the plant. In addition this ''back end'' or post combustion cleanup requires the addition of large vessels, which, in retrofit applications, are difficult to accommodate. As an alternative to post combustion scrubbing, Foster Wheeler (FW) has proposed that the combustion process be accomplished with oxygen rather than air. With all air nitrogen eliminated, a CO{sub 2}-water vapor rich flue gas will be generated. After condensation of the water vapor, a portion of the flue gas will be recirculated back to the boiler to control the combustion temperature and the balance of the CO{sub 2} will be processed for pipeline transport. This proposed oxygen-carbon dioxide (O{sub 2}/CO{sub 2}) combustion process eliminates the need for CO{sub 2} removal/separation and reduces the cost of supplying a CO{sub 2} rich stream for

  12. Controlled temperature expansion in oxygen production by molten alkali metal salts

    DOE Patents [OSTI]

    Erickson, D.C.

    1985-06-04

    A continuous process is set forth for the production of oxygen from an oxygen containing gas stream, such as air, by contacting a feed gas stream with a molten solution of an oxygen acceptor to oxidize the acceptor and cyclically regenerating the oxidized acceptor by releasing oxygen from the acceptor wherein the oxygen-depleted gas stream from the contact zone is treated sequentially to temperature reduction by heat exchange against the feed stream so as to condense out entrained oxygen acceptor for recycle to the process, combustion of the gas stream with fuel to elevate its temperature and expansion of the combusted high temperature gas stream in a turbine to recover power. 1 fig.

  13. Origin of deep subgap states in amorphous indium gallium zinc oxide: Chemically disordered coordination of oxygen

    SciTech Connect (OSTI)

    Sallis, S.; Williams, D. S.; Butler, K. T.; Walsh, A.; Quackenbush, N. F.; Junda, M.; Podraza, N. J.; Fischer, D. A.; Woicik, J. C.; White, B. E.; Piper, L. F. J.

    2014-06-09

    The origin of the deep subgap states in amorphous indium gallium zinc oxide (a-IGZO), whether intrinsic to the amorphous structure or not, has serious implications for the development of p-type transparent amorphous oxide semiconductors. We report that the deep subgap feature in a-IGZO originates from local variations in the oxygen coordination and not from oxygen vacancies. This is shown by the positive correlation between oxygen composition and subgap intensity as observed with X-ray photoelectron spectroscopy. We also demonstrate that the subgap feature is not intrinsic to the amorphous phase because the deep subgap feature can be removed by low-temperature annealing in a reducing environment. Atomistic calculations of a-IGZO reveal that the subgap state originates from certain oxygen environments associated with the disorder. Specifically, the subgap states originate from oxygen environments with a lower coordination number and/or a larger metal-oxygen separation.

  14. Development of a Supersonic Atomic Oxygen Nozzle Beam Source for Crossed Beam Scattering Experiments

    DOE R&D Accomplishments [OSTI]

    Sibener, S. J.; Buss, R. J.; Lee, Y. T.

    1978-05-01

    A high pressure, supersonic, radio frequency discharge nozzle beam source was developed for the production of intense beams of ground state oxygen atoms. An efficient impedance matching scheme was devised for coupling the radio frequency power to the plasma as a function of both gas pressure and composition. Techniques for localizing the discharge directly behind the orifice of a water-cooled quartz nozzle were also developed. The above combine to yield an atomic oxygen beam source which produces high molecular dissociation in oxygen seeded rare gas mixtures at total pressures up to 200 torr: 80 to 90% dissociation for oxygen/argon mixtures and 60 to 70% for oxygen/helium mixtures. Atomic oxygen intensities are found to be greater than 10{sup 17} atom sr{sup -1} sec{sup -1}. A brief discussion of the reaction dynamics of 0 + IC1 ..-->.. I0 + C1 is also presented.

  15. Measurement of the soot concentration and soot particle sizes in propane oxygen flames

    SciTech Connect (OSTI)

    Bockhorn, H.; Fetting, F.; Meyer, U.; Reck, R.; Wannemacher, G.

    1981-01-01

    Soot concentrations and particle sizes were measured by light scattering and probe measurements in the burnt gas region of atmospheric pressure propane-oxygen flames and propane-oxygen flames to which hydrogen or ammonia were added. The results show that the soot concentrations in propane-oxygen flames, to which hydrogen is added are lower compared to propane-oxygen flames. The decrease of soot concentration is much stronger when ammonia is added. Associated with the reduction of soot concentration is a reduction of mean particle size of the soot particles and a lower breadth of the particle size distributions. Electron micrographs of soot particles from the probe measurements showed that soot particles from flames with high soot concentrations (propane oxygen flames) are aggregates with chain or cluster structure while the structure of the particles from flames with lower soot concentration (propane oxygen flames with hydrogen or ammonia added) is more compact. 24 refs.

  16. Oxygen-stabilized zirconium-vanadium-iron alloy

    DOE Patents [OSTI]

    Mendelsohn, M.H.; Gruen, D.M.

    1981-06-16

    An oxygen stabilized intermetallic compound is described which has the formula (Zr/sub 1-x/Ti/sub x/)/sub 2-u/(V/sub 1-y/Fe/sub y/)O/sub z/ where x = 0.0 to 0.9, y = 0.01 to 0.9, z = 0.25 to 0.5 and u = 0 to 1. The compound is capable of reversibly sorbing hydrogen at temperatures from -196/sup 0/C to 200/sup 0/C at pressures down to 10/sup -6/ torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices.

  17. Effects of Ionomer Morphology on Oxygen Reduction on Pt

    SciTech Connect (OSTI)

    Chlistunoff, Jerzy; Pivovar, Bryan

    2015-05-21

    In this paper, the oxygen reduction reaction (ORR) at the interface between platinum and Nafion 1100 equivalent weight was studied as a function of temperature (20–80 °C), humidity (10–100%), scan rate, the manner in which Nafion film was deposited, and the state of the Pt surface using ultramicroelectrodes employing cyclic voltammetry and chronoamperometry. ORR on smooth electrodes was strongly inhibited under specific conditions dependent on temperature, humidity, and scan rate. From the data presented, we postulate that dynamic changes in the molecular structure of the ionomer at the platinum interface result in differences in ORR voltammetry for films prepared and equilibrated under different conditions. The lack of similar changes for rough, platinized electrodes has been attributed to differences in initial ionomer structure and a higher energy barrier for ionomer restructuring. Finally, these model system studies yield insight into the ionomer-catalyst interface of particular interest for polymer electrolyte fuel cells.

  18. Orbital reconstruction in a self-assembled oxygen vacancy nanostructure

    SciTech Connect (OSTI)

    Jang, H.; Kerr, G.; Lim, J. S.; Yang, C. -H.; Kao, C. -C.; Lee, J. -S.

    2015-07-27

    We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1nm) in BiFeO₃, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca²⁺ for Bi³⁺ cation. We found that by increasing the substitution, the in-plane orbital bands of Fe³⁺ cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of the doped BiFeO₃ system.

  19. Willamette Hatchery Oxygen Supplementation Studies : Annual Report 1993.

    SciTech Connect (OSTI)

    Ewing, R.D.; Ewing, S.K.; Sheahan, J.E.

    1993-11-01

    Hydropower development and operations in the Columbia River basin have caused the loss of 5 million to 11 million salmonids. An interim goal of the Northwest Power Planning Council is to reestablish these historical numbers by doubling the present adult runs from 2.5 million to 5.0 million fish. This increase in production will be accomplished through comprehensive management of both wild and hatchery fish, but artificial propagation will play a major role in the augmentation process. The current husbandry techniques in existing hatcheries require improvements that may include changes in rearing densities, addition of oxygen, removal of excess nitrogen, and improvement in raceway design. Emphasis will be placed on the ability to increase the number of fish released from hatcheries that survive to return as adults.

  20. Orbital reconstruction in a self-assembled oxygen vacancy nanostructure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jang, H.; Kerr, G.; Lim, J. S.; Yang, C. -H.; Kao, C. -C.; Lee, J. -S.

    2015-07-27

    We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1nm) in BiFeO₃, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca²⁺ for Bi³⁺ cation. We found that by increasing the substitution, the in-plane orbital bands of Fe³⁺ cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of themore » doped BiFeO₃ system.« less

  1. Complexes of self-interstitials with oxygen atoms in Ge

    SciTech Connect (OSTI)

    Khirunenko, L. I.; Pomozov, Yu. V.; Sosnin, M. G.; Abrosimov, N. V.; Riemann, H.

    2014-02-21

    Interactions of germanium self-interstitials with interstitial oxygen atoms in Ge subjected to irradiation at ?80 K and subsequently to annealing have been studied. To distinguish the processes involving vacancies and self-interstitials the doping with tin was used. It was shown that absorption lines with maximum at 602, 674, 713 and 803 cm{sup ?1} are self-interstitials-related. Two lines at 602 and 674, which develop upon annealing in the temperature range 180240 K, belong to IO complexes, while the bands at 713 and 803 cm{sup ?1}, which emerge after annealing at T>220 K, are associated with I{sub 2}O. It is argued that the annealing of IO occurs by two mechanisms: by dissociation and by diffusion.

  2. Lattice distortions and oxygen vacancies produced in Au+ irradiated nano-crystalline cubic zirconia

    SciTech Connect (OSTI)

    Edmondson, Philip D; Weber, William J; Namavar, Fereydoon; Zhang, Yanwen

    2011-01-01

    The structural impact of oxygen vacancies in nanocrystalline cubic zirconia is investigated. A non-equilibrium number of oxygen vacancies in introduced to the lattice by ion irradiation. The lattice is observed to be initially compressed, undergoes a relaxation at 0.7 displacements per atom (dpa), and experiences a contraction before reaching a temperature dependent steady state value at above 7 dpa. The level of lattice distortion is related to the charge state of the accumulating oxygen vacancies.

  3. Blast furnace injection of massive quantities of coal with enriched air or pure oxygen

    SciTech Connect (OSTI)

    Ponghis, N.; Dufresne, P.; Vidal, R.; Poos, A. )

    1993-01-01

    An extensive study of the phenomena associated with the blast furnace injection of massive quantities of coal is described. Trials with conventional lances or oxy-coal injectors and hot blast at different oxygen contents - up to 40% - or with cold pure oxygen were realized at coal to oxygen ratios corresponding to a range of 150 to 440 kg. Pilot scale rigs, empty or filled with coke, as well as industrial blast furnaces were utilized.

  4. Microsoft Word - sensitive-species-table.docx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1. Sensitive Species Occurring or Potentially Occurring at LANL Scientific Name Common Name Protected Status 1 Potential to Occur 2 Gila pandora Rio Grande Chub NMS Moderate Falco peregrinus anatum American Peregrine Falcon NMT, FSOC High Falco peregrinus tundrius Arctic Peregrine Falcon NMT, FSOC Moderate Haliaeetus leucocephalus Bald Eagle NMT, S1 High Cynanthus latirostris magicus Broad-billed Hummingbird NMT Low Accipiter gentilis Northern Goshawk NMS, FSOC High Lanius ludovicianus

  5. Current generation by minority species heating

    SciTech Connect (OSTI)

    Fisch, N.J.

    1980-07-01

    It is proposed that electric currents be generated from the preferential heating of ions traveling in one direction but with no net momentum injected into the system. This can be accomplished with, for example, traveling waves in a two-ion-species plasma. The current can be generated efficiently enough for the scheme to be of interest in maintaining steady-state toroidal currents in a reactor.

  6. Computer Simulation of Defects and Oxygen Transport in Yttria-Stabilized Zirconia

    SciTech Connect (OSTI)

    Devanathan, Ram; Weber, William J.; Singhal, Subhash C.; Gale, Julian D.

    2006-06-15

    We have used molecular dynamics simulations and energy minimization calculations to examine defect energetics and oxygen diffusion in yttria-stabilized zirconia (YSZ). Oxygen vacancies prefer to be second nearest neighbors to yttrium dopants. The oxygen diffusion coefficient shows a peak at 8 mole % yttria consistent with experimental findings. The activation energy for oxygen diffusion varies from 0.6 to 1.0 eV depending on the yttria content. The Y-Vo-Y complex with a binding energy of -0.85 eV may play an important role in any conductivity degradation of YSZ.

  7. Growth control of oxygen stoichiometry in homoepitaxial SrTiO3...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Growth control of oxygen ... Type: Accepted Manuscript Journal Name: Scientific Reports Additional Journal Information: ...

  8. Surface oxygen micropatterns on glow discharge polymer targets by photo irradiation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Reynolds, Hannah; Baxamusa, Salmaan; Haan, Steven W.; Fitzsimmons, Paul; Carlson, Lane; Farrell, Mike; Nikroo, Abbas; Watson, Brian J.

    2016-02-24

    Recent simulations predict surface oxygen may be a significant source of disruptive perturbations in the implosion process of glow-discharge polymers (GDP) ablators at the National Ignition Facility. GDP material held in ambient atmospheric conditions showed an increase in mass when stored in light transparent containers, which suggests that photo exposure is a driving force for oxygen absorption. To investigate if surface oxygen is a contributing factor of disruptive perturbations during implosion, we developed a method to imprint a periodic micropattern of oxygen on the surface of GDP and used it to fabricate a flat sample for empirical testing.

  9. Low oxygen biomass-derived pyrolysis oils and methods for producing the same

    DOE Patents [OSTI]

    Marinangeli, Richard; Brandvold, Timothy A; Kocal, Joseph A

    2013-08-27

    Low oxygen biomass-derived pyrolysis oils and methods for producing them from carbonaceous biomass feedstock are provided. The carbonaceous biomass feedstock is pyrolyzed in the presence of a catalyst comprising base metal-based catalysts, noble metal-based catalysts, treated zeolitic catalysts, or combinations thereof to produce pyrolysis gases. During pyrolysis, the catalyst catalyzes a deoxygenation reaction whereby at least a portion of the oxygenated hydrocarbons in the pyrolysis gases are converted into hydrocarbons. The oxygen is removed as carbon oxides and water. A condensable portion (the vapors) of the pyrolysis gases is condensed to low oxygen biomass-derived pyrolysis oil.

  10. Cold-Start and Warm-Up Driveability Performance of Hybrid Electric Vehicles Using Oxygenated Fuels

    SciTech Connect (OSTI)

    Thornton, M.; Jorgensen, S.; Evans, B.; Wright, K.

    2003-11-01

    Provides analysis and results of the driveability performance testing from four hybrid electric vehicles--Honda Civic, Toyota Prius, and two Honda Insights--that used oxygenated fuels.

  11. Oxygen-resistant hydrogenases and methods for designing and making same

    DOE Patents [OSTI]

    King, Paul; Ghirardi, Maria L; Seibert, Michael

    2009-03-10

    The invention provides oxygen- resistant iron-hydrogenases ([Fe]-hydrogenases) for use in the production of H2. Methods used in the design and engineering of the oxygen-resistant [Fe]-hydrogenases are disclosed, as are the methods of transforming and culturing appropriate host cells with the oxygen-resistant [Fe]-hydrogenases. Finally, the invention provides methods for utilizing the transformed, oxygen insensitive, host cells in the bulk production of H.sub.2 in a light catalyzed reaction having water as the reactant.

  12. Oxygen-resistant hydrogenases and methods for designing and making same

    DOE Patents [OSTI]

    King, Paul; Ghirardi, Maria Lucia; Seibert, Michael

    2014-03-04

    The invention provides oxygen-resistant iron-hydrogenases ([Fe]-hydrogenases) for use in the production of H.sub.2. Methods used in the design and engineering of the oxygen-resistant [Fe]-hydrogenases are disclosed, as are the methods of transforming and culturing appropriate host cells with the oxygen-resistant [Fe]-hydrogenases. Finally, the invention provides methods for utilizing the transformed, oxygen insensitive, host cells in the bulk production of H.sub.2 in a light catalyzed reaction having water as the reactant.

  13. Resistance-Based Ceramic Ho123 Ionic Conductor for Oxygen Gas...

    Office of Scientific and Technical Information (OSTI)

    The rod showed stable sensing characteristics with good electrical stability and reproducibility with higher sensitivity at low oxygen partial pressure. The sensing property is ...

  14. Nitrogen Oxides as a Chemistry Trap in Detonating Oxygen-Rich...

    Office of Scientific and Technical Information (OSTI)

    Conference: Nitrogen Oxides as a Chemistry Trap in Detonating Oxygen-Rich Materials Citation Details In-Document Search Title: Nitrogen Oxides as a Chemistry Trap in Detonating ...

  15. Enhanced Bifunctional Oxygen Catalysis in Strained LaNiO3 Perovskites...

    Office of Scientific and Technical Information (OSTI)

    low temperature oxygen electro catalysis on noble metal films, leading to significant enhancements in bifunctional activity essential for fuel cells and Metal-air batteries. ...

  16. Task Technical Plan for Studies of Oxygen Consumption in the Catalyzed Hydrolysis of Tetraphenylborate Ion

    SciTech Connect (OSTI)

    Fink, S.D.

    1996-12-20

    This document presents the plan for studies of how dissolved oxygen affects the catalytic decomposition of the tetraphenylborate ion in alkaline aqueous solution.

  17. Anomalous expansion of the copper-apical-oxygen distance in supercondu...

    Office of Scientific and Technical Information (OSTI)

    Anomalous expansion of the copper-apical-oxygen distance in superconducting cuprate bilayers Citation Details In-Document Search Title: Anomalous expansion of the copper-apical-oxy...

  18. Bringing Order to Defects - Making Way for Oxygen to Move | U...

    Office of Science (SC) Website

    Biological and Environmental Research U.S. Department of Energy SC-23Germantown Building ... metal oxide crystal made of strontium (green), chromium (blue), oxygen (red) atoms; the ...

  19. Webinar: Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique

    Broader source: Energy.gov [DOE]

    Video recording of the Fuel Cell Technologies Office webinar, Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique, originally presented on March 12, 2013.

  20. Covalency in Metal-Oxygen Multiple Bonds Evaluated Using Oxygen K-edge Spectroscopy and Electronic Structure Theory

    SciTech Connect (OSTI)

    Minasian, Stefan G.; Keith, Jason M.; Batista, Enrique R.; Boland, Kevin S.; Bradley, Joseph A.; Daly, Scott R.; Kozimor, Stosh A.; Lukens, Wayne W.; Martin, Richard L.; Nordlund, Dennis; Seidler, Gerald T.; Shuh, David K.; Sokaras, Dimosthenis; Tyliszczak, Tolek; Wagner, Gregory L.; Weng, Tsu-Chein; Yang, Ping

    2014-01-01

    Advancing theories of how metal oxygen bonding influences metal oxo properties can expose new avenues for innovation in materials science, catalysis, and biochemistry. Historically, spectroscopic analyses of the transition metal peroxyanions, MO4x-, have formed the basis for new M O bonding theories. Herein, relative changes in M O orbital mixing in MO42- (M = Cr, Mo, W) and MO41- (M = Mn, Tc, Re) are evaluated for the first time by non-resonant inelastic X-ray scattering, X-ray absorption spectroscopy using fluorescence and transmission (via a scanning transmission X-ray microscope), and linear-response density functional theory. The results suggest that moving from Group 6 to Group 7 or down the triads increases M O e () mixing. Meanwhile, t2 mixing ( + ) remains relatively constant within the same Group. These unexpected changes in frontier orbital energy and composition are evaluated in terms of periodic trends in d orbital energy and radial extension.

  1. The combustion kinetics of coal chars in oxygen-enriched environments.

    SciTech Connect (OSTI)

    Shaddix, Christopher R.; Murphy, Jeffrey J.

    2004-09-01

    Oxygen-enhanced and oxygen-fired pulverized coal combustion is actively being investigated to achieve emission reductions and reductions in flue gas cleanup costs, as well as for coal-bed methane and enhanced oil recovery applications. To fully understand the results of pilot scale tests and to accurately predict scale-up performance through CFD modeling, accurate rate expressions are needed to describe coal char combustion under these unconventional combustion conditions. In the work reported here, the combustion rates of two pulverized coal chars have been measured in both conventional and oxygen-enriched atmospheres. A combustion-driven entrained flow reactor equipped with an optical particle-sizing pyrometry diagnostic and a rapid-quench sampling probe has been used for this investigation. Highvale subbituminous coal and a high-volatile eastern United States bituminous coal have been investigated, over oxygen concentrations ranging from 6 to 36 mol% and gas temperatures of 1320-1800 K. The results from these experiments demonstrate that pulverized coal char particles burn under increasing kinetic control in elevated oxygen environments, despite their higher burning rates in these environments. Empirical fits to the data have been successfully performed over the entire range of oxygen concentrations using a single-film oxidation model. Both a simple nth-order Arrhenius expression and an nth-order Langmuir-Hinshelwood kinetic equation provide good fits to the data. Local fits of the nth-order Arrhenius expression to the oxygen-enriched and oxygen-depleted data produce lower residuals in comparison to fits of the entire dataset. These fits demonstrate that the apparent reaction order varies from 0.1 under near-diffusion-limit oxygen-depleted conditions to 0.5 under oxygen-enriched conditions. Burnout predictions show good agreement with measurements. Predicted char particle temperatures tend to be low for combustion in oxygen-depleted environments.

  2. Comparative developmental toxicity of environmentally relevant oxygenated PAHs

    SciTech Connect (OSTI)

    Knecht, Andrea L.; Goodale, Britton C.; Truong, Lisa; Simonich, Michael T.; Swanson, Annika J.; Matzke, Melissa M.; Anderson, Kim A.; Waters, Katrina M.; Tanguay, Robert L.

    2013-09-01

    Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are byproducts of combustion and photo-oxidation of parent PAHs. OPAHs are widely present in the environment and pose an unknown hazard to human health. The developing zebrafish was used to evaluate a structurally diverse set of 38 OPAHs for malformation induction, gene expression changes and mitochondrial function. Zebrafish embryos were exposed from 6 to 120 h post fertilization (hpf) to a dilution series of 38 different OPAHs and evaluated for 22 developmental endpoints. AHR activation was determined via CYP1A immunohistochemistry. Phenanthrenequinone (9,10-PHEQ), 1,9-benz-10-anthrone (BEZO), xanthone (XAN), benz(a)anthracene-7,12-dione (7,12-B[a]AQ), and 9,10-anthraquinone (9,10-ANTQ) were evaluated for transcriptional responses at 48 hpf, prior to the onset of malformations. qRT-PCR was conducted for a number of oxidative stress genes, including the glutathione transferase(gst), glutathione peroxidase(gpx), and superoxide dismutase(sod) families. Bioenergetics was assayed to measure in vivo oxidative stress and mitochondrial function in 26 hpf embryos exposed to OPAHs. Hierarchical clustering of the structure-activity outcomes indicated that the most toxic of the OPAHs contained adjacent diones on 6-carbon moieties or terminal, para-diones on multi-ring structures. 5-carbon moieties with adjacent diones were among the least toxic OPAHs while the toxicity of multi-ring structures with more centralized para-diones varied considerably. 9,10-PHEQ, BEZO, 7,12-B[a]AQ, and XAN exposures increased expression of several oxidative stress related genes and decreased oxygen consumption rate (OCR), a measurement of mitochondrial respiration. Comprehensive in vivo characterization of 38 structurally diverse OPAHs indicated differential AHR dependency and a prominent role for oxidative stress in the toxicity mechanisms. - Highlights: OPAHs are byproducts of combustion present in the environment. OPAHs pose a largely

  3. Oxygen isotope variability within Nautilus shell growth bands

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Linzmeier, Benjamin J.; Kozdon, Reinhard; Peters, Shanan E.; Valley, John W.

    2016-04-21

    Nautilus is often used as an analogue for the ecology and behavior of extinct externally shelled cephalopods. Nautilus shell grows quickly, has internal growth banding, and is widely believed to precipitate aragonite in oxygen isotope equilibrium with seawater. Pieces of shell from a wild-caught Nautilus macromphalus from New Caledonia and from a Nautilus belauensis reared in an aquarium were cast in epoxy, polished, and then imaged. Growth bands were visible in the outer prismatic layer of both shells. The thicknesses of the bands are consistent with previously reported daily growth rates measured in aquarium reared individuals. In situ analysis ofmore » oxygen isotope ratios using secondary ion mass spectrometry (SIMS) with 10 μm beam-spot size reveals inter- and intra-band δ18O variation. In the wild-caught sample, a traverse crosscutting 45 growth bands yielded δ18O values ranging 2.5‰, from +0.9 to -1.6 ‰ (VPDB), a range that is larger than that observed in many serial sampling of entire shells by conventional methods. The maximum range within a single band (~32 μm) was 1.5‰, and 27 out of 41 bands had a range larger than instrumental precision (±2 SD = 0.6‰). The results from the wild individual suggest depth migration is recorded by the shell, but are not consistent with a simple sinusoidal, diurnal depth change pattern. In addition, to create the observed range of δ18O, however, this Nautilus must have traversed a temperature gradient of at least ~12°C, corresponding to approximately 400 m depth change. Isotopic variation was also measured in the aquarium-reared sample, but the pattern within and between bands likely reflects evaporative enrichment arising from a weekly cycle of refill and replacement of the aquarium water. Overall, this work suggests that depth migration behavior in ancient nektonic mollusks could be elucidated by SIMS analysis across individual growth bands.« less

  4. Aquatic species project report: FY 1991

    SciTech Connect (OSTI)

    Brown, L.M. ); Sprague, S. )

    1992-04-01

    This report summarizes the progress and research accomplishments of the Aquatic Species Project, which is managed by the National Renewable Energy Laboratory for the US Department of Energy. The project is focused on applying genetic engineering techniques to enhance the lipid, or oil, production of microalgae. Those lipids can be extracted and processed into high-energy liquid fuels such as diesel. Because microalgae require carbon dioxide, a major greenhouse'' gas, as a nutrient, project researchers also study the role that microalgae could play in a possible global climate change mitigation strategy.

  5. Indirect Gas Species Monitoring Using Tunable Diode Lasers

    DOE Patents [OSTI]

    Von Drasek, William A.; Saucedo, Victor M.

    2005-02-22

    A method for indirect gas species monitoring based on measurements of selected gas species is disclosed. In situ absorption measurements of combustion species are used for process control and optimization. The gas species accessible by near or mid-IR techniques are limited to species that absorb in this spectral region. The absorption strength is selected to be strong enough for the required sensitivity and is selected to be isolated from neighboring absorption transitions. By coupling the gas measurement with a software sensor gas, species not accessible from the near or mid-IR absorption measurement can be predicted.

  6. MONTE CARLO SIMULATION OF METASTABLE OXYGEN PHOTOCHEMISTRY IN COMETARY ATMOSPHERES

    SciTech Connect (OSTI)

    Bisikalo, D. V.; Shematovich, V. I. [Institute of Astronomy of the Russian Academy of Sciences, Moscow (Russian Federation); Grard, J.-C.; Hubert, B. [Laboratory for Planetary and Atmospheric Physics (LPAP), University of Lige, Lige (Belgium); Jehin, E.; Decock, A. [Origines Cosmologiques et Astrophysiques (ORCA), University of Lige (Belgium); Hutsemkers, D. [Extragalactic Astrophysics and Space Observations (EASO), University of Lige (Belgium); Manfroid, J., E-mail: B.Hubert@ulg.ac.be [High Energy Astrophysics Group (GAPHE), University of Lige (Belgium)

    2015-01-01

    Cometary atmospheres are produced by the outgassing of material, mainly H{sub 2}O, CO, and CO{sub 2} from the nucleus of the comet under the energy input from the Sun. Subsequent photochemical processes lead to the production of other species generally absent from the nucleus, such as OH. Although all comets are different, they all have a highly rarefied atmosphere, which is an ideal environment for nonthermal photochemical processes to take place and influence the detailed state of the atmosphere. We develop a Monte Carlo model of the coma photochemistry. We compute the energy distribution functions (EDF) of the metastable O({sup 1}D) and O({sup 1}S) species and obtain the red (630nm) and green (557.7nm) spectral line shapes of the full coma, consistent with the computed EDFs and the expansion velocity. We show that both species have a severely non-Maxwellian EDF, that results in broad spectral lines and the suprathermal broadening dominates due to the expansion motion. We apply our model to the atmosphere of comet C/1996 B2 (Hyakutake) and 103P/Hartley 2. The computed width of the green line, expressed in terms of speed, is lower than that of the red line. This result is comparable to previous theoretical analyses, but in disagreement with observations. We explain that the spectral line shape does not only depend on the exothermicity of the photochemical production mechanisms, but also on thermalization, due to elastic collisions, reducing the width of the emission line coming from the O({sup 1}D) level, which has a longer lifetime.

  7. Study of using oxygen-enriched combustion air for locomotive diesel engines

    SciTech Connect (OSTI)

    Poola, R.B.; Sekar, R.; Assanis, D.N.; Cataldi, G.R.

    1996-12-31

    A thermodynamic simulation is used to study the effects of oxygen-enriched intake air on the performance and nitrogen oxide (NO) emissions of a locomotive diesel engine. The parasitic power of the air separation membrane required to supply the oxygen-enriched air is also estimated. For a given constraint on peak cylinder pressure, the gross and net power output of an engine operating under different levels of oxygen enrichment are compared with those obtained when a high-boost turbocharged engine is used. A 4% increase in peak cylinder pressure can result in an increase in net engine power of approximately 13% when intake air with an oxygen content of 28% by volume is used and fuel injection timing is retarded by 4 degrees. When the engine is turbocharged to a higher inlet boost, the same increase in peak cylinder pressure can improve power by only 4%. If part of the significantly higher exhaust enthalpies available as a result of oxygen enrichment are recovered, the power requirements of the air separator membrane can be met, resulting in substantial net power improvements. Oxygen enrichment with its attendant higher combustion temperatures, reduces emissions of particulates and visible smoke but increases NO emissions (by up to three times at 26% oxygen content). Therefore, exhaust gas after-treatment and heat recovery would be required if the full potential of oxygen enrichment for improving the performance of locomotive diesel engines is to be realized.

  8. Metallic filament formation by aligned oxygen vacancies in ZnO-based resistive switches

    SciTech Connect (OSTI)

    Gu, Tingkun

    2014-05-28

    The electronic structure of ZnO with defects of oxygen vacancies were investigated by using first-principles methods. Some structure models were constructed in order to investigate the effects of the distribution of oxygen vacancies on the electronic properties of ZnO. By analyzing the calculated results, we found that only the aligned oxygen vacancies can form the conducting channel in ZnO, and the transformation of the oxygen vacancy from charged state to neutral state is consistent with the energetics rule of the forming aligned oxygen vacancies. As for the heterojunction of Pt/ZnO/Pt, the oxygen vacancies near the interface of Pt/ZnO depress the local Schottky barrier effectively, and the aligned oxygen vacancies in ZnO form a conducting filament connecting two Pt electrodes. The metallic filament formation in Pt/ZnO/Pt resistive switching cells should be closely related to the carrier injection from Pt electrode into ZnO and the arrangement of oxygen vacancies in ZnO slab.

  9. The effect of plutonium dioxide water surface coverage on the generation of hydrogen and oxygen

    SciTech Connect (OSTI)

    Veirs, Douglas K.; Berg, John M.; Crowder, Mark L.

    2012-06-20

    The conditions for the production of oxygen during radiolysis of water adsorbed onto plutonium dioxide powder are discussed. Studies in the literature investigating the radiolysis of water show that both oxygen and hydrogen can be generated from water adsorbed on high-purity plutonium dioxide powder. These studies indicate that there is a threshold in the amount of water below which oxygen is not generated. The threshold is associated with the number of monolayers of adsorbed water and is shown to occur at approximately two monolayers of molecularly adsorbed water. Material in equilibrium with 50% relative humidity (RH) will be at the threshold for oxygen generation. Using two monolayers of molecularly adsorbed water as the threshold for oxygen production, the total pressure under various conditions is calculated assuming stoichiometric production of hydrogen and oxygen. The specific surface area of the oxide has a strong effect on the final partial pressure. The specific surface areas resulting in the highest pressures within a 3013 container are evaluated. The potential for oxygen generation is mitigated by reduced relative humidity, and hence moisture adsorption, at the oxide surface which occurs if the oxide is warmer than the ambient air. The potential for oxygen generation approaches zero as the temperature difference between the ambient air and the material approaches 6 C.

  10. Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production

    DOE Patents [OSTI]

    Jujasz, Albert J.; Burkhart, James A.; Greenberg, Ralph

    1988-01-01

    A method for the separation of gaseous mixtures such as air and for producing medium purity oxygen, comprising compressing the gaseous mixture in a first compressor to about 3.9-4.1 atmospheres pressure, passing said compressed gaseous mixture in heat exchange relationship with sub-ambient temperature gaseous nitrogen, dividing the cooled, pressurized gaseous mixture into first and second streams, introducing the first stream into the high pressure chamber of a double rectification column, separating the gaseous mixture in the rectification column into a liquid oxygen-enriched stream and a gaseous nitrogen stream and supplying the gaseous nitrogen stream for cooling the compressed gaseous mixture, removing the liquid oxygen-enriched stream from the low pressure chamber of the rectification column and pumping the liquid, oxygen-enriched steam to a predetermined pressure, cooling the second stream, condensing the cooled second stream and evaporating the oxygen-enriched stream in an evaporator-condenser, delivering the condensed second stream to the high pressure chamber of the rectification column, and heating the oxygen-enriched stream and blending the oxygen-enriched stream with a compressed blend-air stream to the desired oxygen concentration.

  11. Impact of oxygenates on petroleum refining part 2: Future outlook

    SciTech Connect (OSTI)

    Unzelman, G.H.

    1995-07-01

    With the move to a more conservative political outlook in the U.S. in 1995, some have voiced the opinion there may be resistance to the Clean Air Act and specifically to reformulated gasoline (RFG). There has been some evidence that substantiates early resistance to RFG, brought about by price hikes as high as 10 cents/gal at the pump. Pennsylvania, Maine, New York and Wisconsin have elected to {open_quotes}opt out{close_quotes} about 200,000 b/d of RFG. Certainly a move of this nature may slow the {open_quotes}opt in{close_quotes} movement in other areas of the U.S. On the other hand, the basic RFG program for nine critical areas in the U.S. will remain in place, and as air-quality limits are exceeded in other regions, they will be forced into the program. The movement toward cleaner air is worldwide, and the U.S. has been a leader in fuel reformulation for the past 25 years. While the movement may falter for various reasons, and fine tuning of regulations is inevitable, the ultimate result will be a U.S. gasoline pool that is largely reformulated - and the presence of oxygenates is fundamental to reformulation.

  12. Effects of Oxygen-Containing Functional Groups on Supercapacitor Performance

    SciTech Connect (OSTI)

    Kerisit, Sebastien N.; Schwenzer, Birgit; Vijayakumar, M.

    2014-07-03

    Molecular dynamics (MD) simulations of the interface between graphene and the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate (BMIM OTf) were carried out to gain molecular-level insights into the performance of graphene-based supercapacitors and, in particular, determine the effects of the presence of oxygen-containing defects at the graphene surface on their integral capacitance. The MD simulations predict that increasing the surface coverage of hydroxyl groups negatively affects the integral capacitance, whereas the effect of the presence of epoxy groups is much less significant. The calculated variations in capacitance are found to be directly correlated to the interfacial structure. Indeed, hydrogen bonding between hydroxyl groups and SO3 anion moieties prevents BMIM+ and OTf- molecules from interacting favorably in the dense interfacial layer and restrains the orientation and mobility of OTf- ions, thereby reducing the permittivity of the ionic liquid at the interface. The results of the molecular simulations can facilitate the rational design of electrode materials for supercapacitors.

  13. Effects of ionomer morphology on oxygen reduction on Pt

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chlistunoff, Jerzy; Pivovar, Bryan

    2015-05-21

    In this paper, the oxygen reduction reaction (ORR) at the interface between platinum and Nafion 1100 equivalent weight was studied as a function of temperature (20–80 °C), humidity (10–100%), scan rate, the manner in which Nafion film was deposited, and the state of the Pt surface using ultramicroelectrodes employing cyclic voltammetry and chronoamperometry. ORR on smooth electrodes was strongly inhibited under specific conditions dependent on temperature, humidity, and scan rate. From the data presented, we postulate that dynamic changes in the molecular structure of the ionomer at the platinum interface result in differences in ORR voltammetry for films prepared andmore » equilibrated under different conditions. The lack of similar changes for rough, platinized electrodes has been attributed to differences in initial ionomer structure and a higher energy barrier for ionomer restructuring. Finally, these model system studies yield insight into the ionomer-catalyst interface of particular interest for polymer electrolyte fuel cells.« less

  14. Electron mobility enhancement in (100) oxygen-inserted silicon channel

    SciTech Connect (OSTI)

    Xu, Nuo; King Liu, Tsu-Jae; Takeuchi, Hideki; Hytha, Marek; Cody, Nyles W.; Stephenson, Robert J.; Mears, Robert J.; Kwak, Byungil; Cha, Seon Yong

    2015-09-21

    High performance improvement (+88% in peak G{sub m} and >30% in linear and saturation region drain currents) was observed for N-MOSFETs with Oxygen-Inserted (OI) Si channel. From TCAD analysis of the C-V measurement data, the improvement was confirmed to be due to electron mobility enhancement of the OI Si channel (+75% at N{sub inv} = 4.0 × 10{sup 12} cm{sup −2} and +25% at N{sub inv} = 8.0 × 10{sup 12} cm{sup −2}). Raman and high-resolution Rutherford backscattering measurements confirmed that negligible strain is induced in the OI Si layer, and hence, it cannot be used to explain the origin of mobility improvement. Poisson-Schrödinger based quantum mechanical simulation was performed, taking into account phonon, surface roughness and Coulomb scatterings. The OI layer was modeled as a “quasi barrier” region with reference to the Si conduction band edge to confine inversion electrons. Simulation explains the measured electron mobility enhancement as the confinement effect of inversion electrons while the formation of an super-steep retrograde well doping profile in the channel (as a result of dopant diffusion blocking effect accompanied by introduction of the OI layer) also contributes 50%–60% of the mobility improvement.

  15. Platinum-Coated Nickel Nanowires as Oxygen-Reducing Electrocatalysts

    SciTech Connect (OSTI)

    Alia, Shaun M; Larsen, Brian A; Pylypenko, Svitlana; Cullen, David A; Diercks, David R; Neyerlin, Kenneth C; Kocha, Shyam S; Pivovar, Bryan

    2014-01-01

    Platinum (Pt)-coated nickel (Ni) nanowires (PtNiNWs) are synthesized by the partial spontaneous galvanic displacement of NiNWs, with a diameter of 150 250 nm and a length of 100 200 m. PtNiNWs are electrochemically characterized for oxygen reduction (ORR) in rotating disk electrode half-cells with an acidic electrolyte and compared to carbon-supported Pt (Pt/HSC) and a polycrystalline Pt electrode. Like other extended surface catalysts, the nanowire morphology yields significant gains in ORR specific activity compared to Pt/HSC. Unlike other extended surface approaches, the resultant materials have yielded exceptionally high surface areas, greater than 90 m2 gPt 1. These studies have found that reducing the level of Pt displacement increases Pt surface area and ORR mass activity. PtNiNWs produce a peak mass activity of 917 mA mgPt 1, 3.0 times greater than Pt/HSC and 2.1 times greater than the U.S. Department of Energy target for proton-exchange membrane fuel cell activity.

  16. Oxygen sensor for monitoring gas mixtures containing hydrocarbons

    DOE Patents [OSTI]

    Ruka, Roswell J.; Basel, Richard A.

    1996-01-01

    A gas sensor measures O.sub.2 content of a reformable monitored gas containing hydrocarbons H.sub.2 O and/or CO.sub.2, preferably in association with an electrochemical power generation system. The gas sensor has a housing communicating with the monitored gas environment and carries the monitored gas through an integral catalytic hydrocarbon reforming chamber containing a reforming catalyst, and over a solid electrolyte electrochemical cell used for sensing purposes. The electrochemical cell includes a solid electrolyte between a sensor electrode that is exposed to the monitored gas, and a reference electrode that is isolated in the housing from the monitored gas and is exposed to a reference gas environment. A heating element is also provided in heat transfer communication with the gas sensor. A circuit that can include controls operable to adjust operations via valves or the like is connected between the sensor electrode and the reference electrode to process the electrical signal developed by the electrochemical cell. The electrical signal varies as a measure of the equilibrium oxygen partial pressure of the monitored gas. Signal noise is effectively reduced by maintaining a constant temperature in the area of the electrochemical cell and providing a monitored gas at chemical equilibria when contacting the electrochemical cell. The output gas from the electrochemical cell of the sensor is fed back into the conduits of the power generating system.

  17. Oxygen sensor for monitoring gas mixtures containing hydrocarbons

    DOE Patents [OSTI]

    Ruka, R.J.; Basel, R.A.

    1996-03-12

    A gas sensor measures O{sub 2} content of a reformable monitored gas containing hydrocarbons, H{sub 2}O and/or CO{sub 2}, preferably in association with an electrochemical power generation system. The gas sensor has a housing communicating with the monitored gas environment and carries the monitored gas through an integral catalytic hydrocarbon reforming chamber containing a reforming catalyst, and over a solid electrolyte electrochemical cell used for sensing purposes. The electrochemical cell includes a solid electrolyte between a sensor electrode that is exposed to the monitored gas, and a reference electrode that is isolated in the housing from the monitored gas and is exposed to a reference gas environment. A heating element is also provided in heat transfer communication with the gas sensor. A circuit that can include controls operable to adjust operations via valves or the like is connected between the sensor electrode and the reference electrode to process the electrical signal developed by the electrochemical cell. The electrical signal varies as a measure of the equilibrium oxygen partial pressure of the monitored gas. Signal noise is effectively reduced by maintaining a constant temperature in the area of the electrochemical cell and providing a monitored gas at chemical equilibria when contacting the electrochemical cell. The output gas from the electrochemical cell of the sensor is fed back into the conduits of the power generating system. 4 figs.

  18. The reaction of hydroperoxy-propyl radicals with molecular oxygen

    SciTech Connect (OSTI)

    Bozzelli, J.W.; Pitz, W.J.

    1993-12-03

    Addition of hydroperoxy-alkyl radicals to molecular oxygen leads to chain branching in autoignition and engine knock, and in low temperature oxidation of paraffins. Rate constants and product channels for reaction of hydroperoxy-propyl radicals with O{sub 2} are estimated using thermodynamic properties, bimolecular quantum Kassel analysis and transition state theory. Thermochemistry of relevant molecules and radicals is estimated using group additivity and bond dissociation groups for radicals. Results show that rates of the hydroperoxy-propyl radical addition to O{sub 2} are near their high pressure limits at {ge} 1 atm. Main products at 1--15 atm are stabilization, reverse reaction to hydroperoxy-propyl + O{sub 2} and alkyl carbonyl + OH. Reactions of the stabilized adducts, dissociation rates and product channels are estimated using unimolecular quantum Kassel analysis, because stabilization is the most important hydroperoxy-propyl radical + O{sub 2} product channel. Below 700 K, the stabilized peroxy adducts react primarily to hydroperoxy-carbonyl + OH, products which lead to chain branching. Above 700K, the stabilized peroxy adducts react primarily to hydroperoxy-propyl radical + O{sub 2}, initial reactants, which inhibits the overall oxidation. This switchover in channels correlates well observed negative temperature coefficient behavior for propane oxidation. Rate expressions for reaction of each of the three hydroperoxy-alkyl isomers with O{sub 2} and for dissociation of the associated stabilized adducts are calculated for a series of pressures at 300--2100K.

  19. Porous platinum-based catalysts for oxygen reduction

    DOE Patents [OSTI]

    Erlebacher, Jonah D; Snyder, Joshua D

    2014-11-25

    A porous metal that comprises platinum and has a specific surface area that is greater than 5 m.sup.2/g and less than 75 m.sup.2/g. A fuel cell includes a first electrode, a second electrode spaced apart from the first electrode, and an electrolyte arranged between the first and the second electrodes. At least one of the first and second electrodes is coated with a porous metal catalyst for oxygen reduction, and the porous metal catalyst comprises platinum and has a specific surface area that is greater than 5 m.sup.2/g and less than 75 m.sup.2/g. A method of producing a porous metal according to an embodiment of the current invention includes producing an alloy consisting essentially of platinum and nickel according to the formula Pt.sub.xNi.sub.1-x, where x is at least 0.01 and less than 0.3; and dealloying the alloy in a substantially pH neutral solution to reduce an amount of nickel in the alloy to produce the porous metal.

  20. Chemical expansion affected oxygen vacancy stability in different oxide structures from first principles calculations

    SciTech Connect (OSTI)

    Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2015-03-01

    We study the chemical expansion for neutral and charged oxygen vacancies in fluorite, rocksalt, perovskite and pyrochlores materials using first principles calculations. We show that the neutral oxygen vacancy leads to lattice expansion whereas the charged vacancy leads to lattice contraction. In addition, we show that there is a window of strain within which an oxygen vacancy is stable; beyond that range, the vacancy can become unstable. Using CeO2|ZrO2 interface structure as an example, we show that the concentration of oxygen vacancies can be manipulated via strain, and the vacancies can be preferentially stabilized. These results could serve as guiding principles in predicting oxygen vacancy stability in strained systems and in the design of vacancy stabilized materials.

  1. THE OXYGEN PERMEATION PROPERTIES OF NANO CRYSTALLINE CEO2 THIN FILMS

    SciTech Connect (OSTI)

    Brinkman, K.

    2010-09-27

    The measurement of oxygen flux across nanocrystalline CeO{sub 2} cerium oxide thin films at intermediate temperature (650 to 800 C) is presented. Porous ceria support substrates were fabricated by sintering with carbon additions. The final dense film was deposited from an optimized sol-gel solution resulting in a mean grain size of 50 nm which displayed oxygen flux values of up to 0.014 {micro}mol/cm{sup 2}s over the oxygen partial pressure range from air to helium gas used in the measurement at 800 C. The oxygen flux characteristics confirm mixed ionic and electronic conductivity in nanocrystalline ceria films and demonstrate the role of size dependent materials properties as a design parameter in functional membranes for oxygen separation.

  2. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOE Patents [OSTI]

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials. 8 figs.

  3. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOE Patents [OSTI]

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials.

  4. EPA`s proposed renewable oxygenate requirement (ROR): Pros and cons

    SciTech Connect (OSTI)

    Czeskleba, H.M.

    1995-12-31

    In December 1993, the US Environmental Protection Agency (EPA) released its final rule that sets for the details for requirements to sell reformulated gasoline (RFG) in certain ozone non-attainment areas. At the same time, EPA also issued a proposed rule to require that 30% of the oxygen required in RFG be based on a renewable oxygenate. Renewables include ethanol and its ether derivatives such as ethyl tertiary butyl ether (ETBE). The RFG rule is a final rule, while the Renewable Oxygenate Requirement (ROR) rule is a proposed rule yet to be finalized and subject to revision. Included in this paper are brief reviews of Ashland petroleum Company`s ethanol usage, oxygenated fuel and reformulated gasoline blending economics, and some comments on the EPA proposed renewable oxygenate requirement.

  5. Chemical expansion affected oxygen vacancy stability in different oxide structures from first principles calculations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2015-01-21

    We study the chemical expansion for neutral and charged oxygen vacancies in fluorite, rocksalt, perovskite and pyrochlores materials using first principles calculations. We show that the neutral oxygen vacancy leads to lattice expansion whereas the charged vacancy leads to lattice contraction. In addition, we show that there is a window of strain within which an oxygen vacancy is stable; beyond that range, the vacancy can become unstable. Using CeO2|ZrO2 interface structure as an example, we show that the concentration of oxygen vacancies can be manipulated via strain, and the vacancies can be preferentially stabilized. Furthermore, these results could serve asmore » guiding principles in predicting oxygen vacancy stability in strained systems and in the design of vacancy stabilized materials.« less

  6. Attenuation of wall disturbances in an electron cyclotron resonance oxygenargon plasma using real time control

    SciTech Connect (OSTI)

    Keville, Bernard, E-mail: bernard.keville@dcu.ie; Gaman, Cezar; Turner, Miles M. [National Centre for Plasma Science and Technology (NCPST), Research and Engineering Building, Dublin City University, Glasnevin, Dublin 9, Ireland and School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9 (Ireland); Zhang, Yang; Daniels, Stephen [National Centre for Plasma Science and Technology (NCPST), Research and Engineering Building, Dublin City University, Glasnevin, Dublin 9, Ireland and School of Electronic Engineering, Dublin City University, Glasnevin, Dublin 9 (Ireland); Holohan, Anthony M. [School of Electronic Engineering, Dublin City University, Glasnevin, Dublin 9 (Ireland)

    2014-07-01

    Present practice in plasma-assisted semiconductor manufacturing specifies recipes in terms of inputs such as gas flow rates, power and pressure. However, ostensibly identical chambers running identical recipes may produce very different results. Extensive chamber matching, i.e., initial iterative, empirical tuning of the process recipe, which entails time-consuming, ex situ statistical analysis of process metrics such as etch depth, uniformity, anisotropy and selectivity, is required to ensure acceptable results. Once matched, chambers are run open loop and are thus sensitive to disturbances such as actuator drift, wall seasoning and substrate loading, which may impact negatively on process reproducibility. An alternative approach, which may obviate the need for chamber matching and reduce the sensitivity of process metrics to exogenous disturbances, would be to specify a recipe in terms of quantities such as active species densities, and to regulate these in real time by adjusting the inputs with a suitable control algorithm. In this work, real time control of an electron cyclotron resonance O{sub 2}/Ar plasma used for photoresist ashing has been implemented. The design of elementary, model-based algorithms for the control of the argon 750 and oxygen 844 line intensities measured by optical emission spectroscopy is described. Fluorination of the chamber walls by means of an SF{sub 6} plasma prior to ashing inhibits wall recombination of oxygen radicals resulting in an approximately 20% increase in ash rate in the open loop case. However, closed loop control almost completely attenuates the effect of fluorination, thus demonstrating the efficacy of the control algorithms in ensuring a reproducible ash rate in the face of a wall disturbance.

  7. Development of ITM oxygen technology for integration in IGCC and other advanced power generation

    SciTech Connect (OSTI)

    Armstrong, Phillip A.

    2015-03-31

    Ion Transport Membrane (ITM) technology is based on the oxygen-ion-conducting properties of certain mixed-metal oxide ceramic materials that can separate oxygen from an oxygen-containing gas, such as air, under a suitable driving force. The “ITM Oxygen” air separation system that results from the use of such ceramic membranes produces a hot, pure oxygen stream and a hot, pressurized, oxygen-depleted stream from which significant amounts of energy can be extracted. Accordingly, the technology integrates well with other high-temperature processes, including power generation. Air Products and Chemicals, Inc., the Recipient, in conjunction with a dozen subcontractors, developed ITM Oxygen technology under this five-phase Cooperative Agreement from the laboratory bench scale to implementation in a pilot plant capable of producing power and 100 tons per day (TPD) of purified oxygen. A commercial-scale membrane module manufacturing facility (the “CerFab”), sized to support a conceptual 2000 TPD ITM Oxygen Development Facility (ODF), was also established and operated under this Agreement. In the course of this work, the team developed prototype ceramic production processes and a robust planar ceramic membrane architecture based on a novel ceramic compound capable of high oxygen fluxes. The concept and feasibility of the technology was thoroughly established through laboratory pilot-scale operations testing commercial-scale membrane modules run under industrial operating conditions with compelling lifetime and reliability performance that supported further scale-up. Auxiliary systems, including contaminant mitigation, process controls, heat exchange, turbo-machinery, combustion, and membrane pressure vessels were extensively investigated and developed. The Recipient and subcontractors developed efficient process cycles that co-produce oxygen and power based on compact, low-cost ITMs. Process economics assessments show significant benefits relative to state

  8. NMS 17-2-41 Endangered Species | Open Energy Information

    Open Energy Info (EERE)

    NMS 17-2-41 Endangered Species Jump to: navigation, search OpenEI Reference LibraryAdd to library Legal Document- StatuteStatute: NMS 17-2-41 Endangered SpeciesLegal Abstract This...

  9. Utah Sensitive Species List Webpage | Open Energy Information

    Open Energy Info (EERE)

    Species List Webpage Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Utah Sensitive Species List Webpage Abstract Provides access to Utah Sensitive...

  10. Oxygen distribution in tumors: A qualitative analysis and modeling study providing a novel Monte Carlo approach

    SciTech Connect (OSTI)

    Lagerlöf, Jakob H.; Kindblom, Jon; Bernhardt, Peter

    2014-09-15

    Purpose: To construct a Monte Carlo (MC)-based simulation model for analyzing the dependence of tumor oxygen distribution on different variables related to tumor vasculature [blood velocity, vessel-to-vessel proximity (vessel proximity), and inflowing oxygen partial pressure (pO{sub 2})]. Methods: A voxel-based tissue model containing parallel capillaries with square cross-sections (sides of 10 μm) was constructed. Green's function was used for diffusion calculations and Michaelis-Menten's kinetics to manage oxygen consumption. The model was tuned to approximately reproduce the oxygenational status of a renal carcinoma; the depth oxygenation curves (DOC) were fitted with an analytical expression to facilitate rapid MC simulations of tumor oxygen distribution. DOCs were simulated with three variables at three settings each (blood velocity, vessel proximity, and inflowing pO{sub 2}), which resulted in 27 combinations of conditions. To create a model that simulated variable oxygen distributions, the oxygen tension at a specific point was randomly sampled with trilinear interpolation in the dataset from the first simulation. Six correlations between blood velocity, vessel proximity, and inflowing pO{sub 2} were hypothesized. Variable models with correlated parameters were compared to each other and to a nonvariable, DOC-based model to evaluate the differences in simulated oxygen distributions and tumor radiosensitivities for different tumor sizes. Results: For tumors with radii ranging from 5 to 30 mm, the nonvariable DOC model tended to generate normal or log-normal oxygen distributions, with a cut-off at zero. The pO{sub 2} distributions simulated with the six-variable DOC models were quite different from the distributions generated with the nonvariable DOC model; in the former case the variable models simulated oxygen distributions that were more similar to in vivo results found in the literature. For larger tumors, the oxygen distributions became truncated in the

  11. Recovery Act: Novel Oxygen Carriers for Coal-fueled Chemical Looping

    SciTech Connect (OSTI)

    Pan, Wei-Ping; Cao, Yan

    2012-11-30

    Chemical Looping Combustion (CLC) could totally negate the necessity of pure oxygen by using oxygen carriers for purification of CO{sub 2} stream during combustion. It splits the single fuel combustion reaction into two linked reactions using oxygen carriers. The two linked reactions are the oxidation of oxygen carriers in the air reactor using air, and the reduction of oxygen carriers in the fuel reactor using fuels (i.e. coal). Generally metal/metal oxides are used as oxygen carriers and operated in a cyclic mode. Chemical looping combustion significantly improves the energy conversion efficiency, in terms of the electricity generation, because it improves the reversibility of the fuel combustion process through two linked parallel processes, compared to the conventional combustion process, which is operated far away from its thermo-equilibrium. Under the current carbon-constraint environment, it has been a promising carbon capture technology in terms of fuel combustion for power generation. Its disadvantage is that it is less mature in terms of technological commercialization. In this DOE-funded project, accomplishment is made by developing a series of advanced copper-based oxygen carriers, with properties of the higher oxygen-transfer capability, a favorable thermodynamics to generate high purity of CO{sub 2}, the higher reactivity, the attrition-resistance, the thermal stability in red-ox cycles and the achievement of the auto-thermal heat balance. This will be achieved into three phases in three consecutive years. The selected oxygen carriers with final-determined formula were tested in a scaled-up 10kW coal-fueled chemical looping combustion facility. This scaled-up evaluation tests (2-day, 8-hour per day) indicated that, there was no tendency of agglomeration of copper-based oxygen carriers. Only trace-amount of coke or carbon deposits on the copper-based oxygen carriers in the fuel reactor. There was also no evidence to show the sulphidization of oxygen

  12. EO 13112: Invasive Species (1999) | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EO 13112: Invasive Species (1999) EO 13112: Invasive Species (1999) EO 13112: Invasive Species (51.32 KB) More Documents & Publications EO 13089 -- Coral Reef Protection EA-2006: Draft Environmental Assessment Memorandum of Understanding, Responsibilities of Federal Agencies to Protect Migratory Birds

  13. Extension of the JCZ product species database

    SciTech Connect (OSTI)

    Hobbs, M.L.; Baer, M.R.; McGee, B.C.

    1998-09-01

    A database has been created for use with the Jacobs-Cowperthwaite-Zwisler-3 equation-of-state (JCZ3-EOS) to determine thermochemical equilibrium states for energetic materials. The JCZ3-EOS uses the exponential 6 intermolecular potential function to describe interactions between molecules. Product species are characterized by r{sup *}, the radius of the minimum pair potential energy, and {var_epsilon}/{kappa}, the well depth energy normalized by Boltzmann`s constant. These parameters constitute the JCZS (S for Sandia) database describing 750 gases listed in the JANNAF tables and were obtained by using literature values of the Lennard-Jones potential, a corresponding states theory, pure liquid shock Hugoniot data, and fit values to an empirical EOS. Detonation velocities predicted with the JCZS database for a wide variety of explosives are in good agreement with data. Improved predictions of low density explosives is attributed to a better description of molecular interactions at intermediate pressures.

  14. Volatile Species Retention During Metallic Fuel Casting

    SciTech Connect (OSTI)

    Randall S. Fielding; Douglas L. Proter

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, although the loss values varied from the model results the same trend was seen. Bases on these results it is very probably that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  15. Catalytic Synthesis of Oxygenates: Mechanisms, Catalysts and Controlling Characteristics

    SciTech Connect (OSTI)

    Klier, Kamil; Herman, Richard G

    2005-11-30

    This research focused on catalytic synthesis of unsymmetrical ethers as a part of a larger program involving oxygenated products in general, including alcohols, ethers, esters, carboxylic acids and their derivatives that link together environmentally compliant fuels, monomers, and high-value chemicals. The catalysts studied here were solid acids possessing strong Brnsted acid functionalities. The design of these catalysts involved anchoring the acid groups onto inorganic oxides, e.g. surface-grafted acid groups on zirconia, and a new class of mesoporous solid acids, i.e. propylsulfonic acid-derivatized SBA-15. The former catalysts consisted of a high surface concentration of sulfate groups on stable zirconia catalysts. The latter catalyst consists of high surface area, large pore propylsulfonic acid-derivatized silicas, specifically SBA-15. In both cases, the catalyst design and synthesis yielded high concentrations of acid sites in close proximity to one another. These materials have been well-characterization in terms of physical and chemical properties, as well as in regard to surface and bulk characteristics. Both types of catalysts were shown to exhibit high catalytic performance with respect to both activity and selectivity for the bifunctional coupling of alcohols to form ethers, which proceeds via an efficient SN2 reaction mechanism on the proximal acid sites. This commonality of the dual-site SN2 reaction mechanism over acid catalysts provides for maximum reaction rates and control of selectivity by reaction conditions, i.e. pressure, temperature, and reactant concentrations. This research provides the scientific groundwork for synthesis of ethers for energy applications. The synthesized environmentally acceptable ethers, in part derived from natural gas via alcohol intermediates, exhibit high cetane properties, e.g. methylisobutylether with cetane No. of 53 and dimethylether with cetane No. of 55-60, or high octane properties, e.g. diisopropylether with

  16. Regulatory approaches for addressing dissolved oxygen concerns at hydropower facilities

    SciTech Connect (OSTI)

    Peterson, Mark J.; Cada, Glenn F.; Sale, Michael J.; Eddlemon, Gerald K.

    2003-03-01

    Low dissolved oxygen (DO) concentrations are a common water quality problem downstream of hydropower facilities. At some facilities, structural improvements (e.g. installation of weir dams or aerating turbines) or operational changes (e.g., spilling water over the dam) can be made to improve DO levels. In other cases, structural and operational approaches are too costly for the project to implement or are likely to be of limited effectiveness. Despite improvements in overall water quality below dams in recent years, many hydropower projects are unable to meet state water quality standards for DO. Regulatory agencies in the U.S. are considering or implementing dramatic changes in their approach to protecting the quality of the Nations waters. New policies and initiatives have emphasized flexibility, increased collaboration and shared responsibility among all parties, and market-based, economic incentives. The use of new regulatory approaches may now be a viable option for addressing the DO problem at some hydropower facilities. This report summarizes some of the regulatory-related options available to hydropower projects, including negotiation of site-specific water quality criteria, use of biological monitoring, watershed-based strategies for the management of water quality, and watershed-based trading. Key decision points center on the health of the local biological communities and whether there are contributing impacts (i.e., other sources of low DO effluents) in the watershed. If the biological communities downstream of the hydropower project are healthy, negotiation for site-specific water quality standards or biocriteria (discharge performance criteria based on characteristics of the aquatic biota) might be pursued. If there are other effluent dischargers in the watershed that contribute to low DO problems, watershed-scale strategies and effluent trading may be effective. This report examines the value of regulatory approaches by reviewing their use in other

  17. Abiotic ozone and oxygen in atmospheres similar to prebiotic Earth

    SciTech Connect (OSTI)

    Domagal-Goldman, Shawn D.; Segura, Antígona; Claire, Mark W.; Robinson, Tyler D.; Meadows, Victoria S.

    2014-09-10

    The search for life on planets outside our solar system will use spectroscopic identification of atmospheric biosignatures. The most robust remotely detectable potential biosignature is considered to be the detection of oxygen (O{sub 2}) or ozone (O{sub 3}) simultaneous to methane (CH{sub 4}) at levels indicating fluxes from the planetary surface in excess of those that could be produced abiotically. Here we use an altitude-dependent photochemical model with the enhanced lower boundary conditions necessary to carefully explore abiotic O{sub 2} and O{sub 3} production on lifeless planets with a wide variety of volcanic gas fluxes and stellar energy distributions. On some of these worlds, we predict limited O{sub 2} and O{sub 3} buildup, caused by fast chemical production of these gases. This results in detectable abiotic O{sub 3} and CH{sub 4} features in the UV-visible, but no detectable abiotic O{sub 2} features. Thus, simultaneous detection of O{sub 3} and CH{sub 4} by a UV-visible mission is not a strong biosignature without proper contextual information. Discrimination between biological and abiotic sources of O{sub 2} and O{sub 3} is possible through analysis of the stellar and atmospheric context—particularly redox state and O atom inventory—of the planet in question. Specifically, understanding the spectral characteristics of the star and obtaining a broad wavelength range for planetary spectra should allow more robust identification of false positives for life. This highlights the importance of wide spectral coverage for future exoplanet characterization missions. Specifically, discrimination between true and false positives may require spectral observations that extend into infrared wavelengths and provide contextual information on the planet's atmospheric chemistry.

  18. Negative Valve Overlap Reforming Chemistry in Low-Oxygen Environments

    SciTech Connect (OSTI)

    Szybist, James P; Steeper, Richard R.; Splitter, Derek A; Kalaskar, Vickey B; Pihl, Josh A; Daw, C Stuart

    2014-01-01

    Fuel injection into the negative valve overlap (NVO) period is a common method for controlling combustion phasing in homogeneous charge compression ignition (HCCI) and other forms of advanced combustion. When fuel is injected into O2-deficient NVO conditions, a portion of the fuel can be converted to products containing significant levels of H2 and CO. Additionally, other short chain hydrocarbons are produced by means of thermal cracking, water-gas shift, and partial oxidation reactions. The present study experimentally investigates the fuel reforming chemistry that occurs during NVO. To this end, two very different experimental facilities are utilized and their results are compared. One facility is located at Oak Ridge National Laboratory, which uses a custom research engine cycle developed to isolate the NVO event from main combustion, allowing a steady stream of NVO reformate to be exhausted from the engine and chemically analyzed. The other experimental facility, located at Sandia National Laboratories, uses a dump valve to capture the exhaust from a single NVO event for analysis. Results from the two experiments are in excellent trend-wise agreement and indicate that the reforming process under low-O2 conditions produces substantial concentrations of H2, CO, methane, and other short-chain hydrocarbon species. The concentration of these species is found to be strongly dependent on fuel injection timing and injected fuel type, with weaker dependencies on NVO duration and initial temperature, indicating that NVO reforming is kinetically slow. Further, NVO reforming does not require a large energy input from the engine, meaning that it is not thermodynamically expensive. The implications of these results on HCCI and other forms of combustion are discussed in detail.

  19. Simulation studies of diesel engine performance with oxygen enriched air and water emulsified fuels

    SciTech Connect (OSTI)

    Assanis, D.N.; Baker, D. ); Sekar, R.R.; Siambekos, C.T.; Cole, R.L.; Marciniak, T.J. )

    1990-01-01

    A computer simulation code of a turbocharged, turbocompound diesel engine was modified to study the effects of using oxygen-enriched combustion air and water-emulsified diesel fuels. Oxygen levels of 21 percent to 40 percent by volume in the combustion air were studied. Water content in the fuel was varied from 0 percent to 50 percent mass. Simulation studies and a review and analysis of previous work in this area led to the following conclusions about expected engine performance and emissions: the power density of the engine is significantly increased by oxygen enrichment. Ignition delay and particulate emissions are reduced. Combustion temperatures and No{sub x} emissions are increased with oxygen enrichment but could be brought back to the base levels by introducing water in the fuel. The peak cylinder pressure which increases with the power output level might result in mechanical problems with engine components. Oxygen enrichment also provides an opportunity to use cheaper fuel such as No. 6 diesel fuel. Overall, the adverse effects of oxygen enrichment could be countered by the addition of water and it appears that an optimum combination of water content, oxygen level, and base diesel fuel quality may exist. This could yield improved performance and emissions characteristics compared to a state-of-the-art diesel engine. 9 refs., 8 figs.

  20. Segregation and Migration of the Oxygen Vacancies in the 3 (111) Tilt Grain Boundaries of Ceria

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yuan, Fenglin; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2016-03-01

    In nanocrystalline materials, defect-grain boundary (GB) interaction plays a key role in determining the structure stability, as well as size-dependent ionic, electronic, magnetic and chemical properties. In this study, we systematically investigated using density functional theory segregation and migration of oxygen vacancies at the Σ3 [110] / (111) grain boundary of ceria. Three oxygen layers near the GB are predicted to be segregation sites for oxygen vacancies. Moreover, the presence of oxygen vacancies stabilizes this tilt GB at a low Fermi level and/or oxygen poor conditions. An atomic strain model was proposed to rationalize layer dependency of the relaxation energymore » for +2 charged oxygen vacancy. The structural origin of large relaxation energies at layers 1 and 2 was determined to be free-volume space that induces ion relaxation towards the GB. Our results not only pave the way for improving the oxygen transport near GBs of ceria, but also provide important insights into engineering the GB structure for better ionic, magnetic and chemical properties of nanocrystalline ceria.« less

  1. Oxygen Electroreduction on Nanoscale Pt/[TaOPO4/VC] and Pt/[Ta2O5...

    Office of Scientific and Technical Information (OSTI)

    Oxygen Electroreduction on Nanoscale PtTaOPO4VC and PtTa2O5VC in Alkaline Electrolyte Citation Details In-Document Search Title: Oxygen Electroreduction on Nanoscale Pt...

  2. Resonant elastic soft x-ray scattering in oxygen-ordered YBa2Cu3O6...

    Office of Scientific and Technical Information (OSTI)

    Resonant elastic soft x-ray scattering in oxygen-ordered YBa2Cu3O6+ Citation Details In-Document Search Title: Resonant elastic soft x-ray scattering in oxygen-ordered...

  3. Method for oxygen reduction in a uranium-recovery process. [US DOE patent application

    DOE Patents [OSTI]

    Hurst, F.J.; Brown, G.M.; Posey, F.A.

    1981-11-04

    An improvement in effecting uranium recovery from phosphoric acid solutions is provided by sparging dissolved oxygen contained in solutions and solvents used in a reductive stripping stage with an effective volume of a nonoxidizing gas before the introduction of the solutions and solvents into the stage. Effective volumes of nonoxidizing gases, selected from the group consisting of argon, carbon dioxide, carbon monoxide, helium, hydrogen, nitrogen, sulfur dioxide, and mixtures thereof, displace oxygen from the solutions and solvents thereby reduce deleterious effects of oxygen such as excessive consumption of elemental or ferrous iron and accumulation of complex iron phosphates or cruds.

  4. How a weird Mars rock may be solid proof of an ancient oxygen atmosphere

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Weird Mars rock may be solid proof of ancient oxygen atmosphere How a weird Mars rock may be solid proof of an ancient oxygen atmosphere When researchers found a compound that shouldn't have been there, it revealed a missing piece of Mars' history. August 1, 2016 How a weird Mars rock may be solid proof of an ancient oxygen atmosphere The Gale Crater captured by the Thermal Emission Imaging System (THEMIS) on NASA's Mars Odyssey orbiter. CREDIT: NASA/JPL-Caltech/Arizona State University How a

  5. Preparation of low oxygen-to-metal mixed oxide fuels for the advanced fast reactor

    SciTech Connect (OSTI)

    Kato, Masato; Nakamichi, Shinya; Takano, Tatsuo

    2007-07-01

    The preparation process for homogeneous mixed oxide pellets with a precise O/M ratio was established. The process was used to prepare pellets for heat treatments in two stages which consisted of the sintering process at high oxygen potential and the annealing process done in the atmosphere of controlled oxygen partial pressure. In the annealing process, it was found that abnormal growth of pores and occurrence of cracks were caused inside the pellet, and it was necessary for prevention of the microstructure change to control the oxygen potential of the atmosphere. Mixed oxide pellets with minor actinides were fabricated by the process and were provided to irradiation tests. (authors)

  6. Design of generic coal conversion facilities: Production of oxygenates from synthesis gas---A technology review

    SciTech Connect (OSTI)

    Not Available

    1991-10-01

    This report concentrates on the production of oxygenates from coal via gasification and indirect liquefaction. At the present the majority of oxygenate synthesis programs are at laboratory scale. Exceptions include commercial and demonstration scale plants for methanol and higher alcohols production, and ethers such as MTBE. Research and development work has concentrated on elucidating the fundamental transport and kinetic limitations governing various reactor configurations. But of equal or greater importance has been investigations into the optimal catalyst composition and process conditions for the production of various oxygenates.

  7. Removing oxygen from a solvent extractant in an uranium recovery process

    DOE Patents [OSTI]

    Hurst, Fred J.; Brown, Gilbert M.; Posey, Franz A.

    1984-01-01

    An improvement in effecting uranium recovery from phosphoric acid solutions is provided by sparging dissolved oxygen contained in solutions and solvents used in a reductive stripping stage with an effective volume of a nonoxidizing gas before the introduction of the solutions and solvents into the stage. Effective volumes of nonoxidizing gases, selected from the group consisting of argon, carbon dioxide, carbon monoxide, helium, hydrogen, nitrogen, sulfur dioxide, and mixtures thereof, displace oxygen from the solutions and solvents thereby reduce deleterious effects of oxygen such as excessive consumption of elemental or ferrous and accumulation of complex iron phosphates or cruds.

  8. Landscape corridors can increase invasion by an exotic species and reduce diversity of native species.

    SciTech Connect (OSTI)

    Resasco, Julian; et al,

    2014-04-01

    Abstract. Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta, and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors than in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species traits when assessing corridor utility.

  9. Thermoelectric misfit-layered cobalt oxides with interlayers of hydroxide and peroxide species

    SciTech Connect (OSTI)

    Chou, Ta-Lei; Lybeck, Jenni; Chan, Ting-Shan; Hsu, Ying-Ya; Tewari, Girish C.; Rautama, Eeva-Leena; Yamauchi, Hisao; Karppinen, Maarit

    2013-12-15

    Among the thermoelectric misfit-layered cobalt oxides, [M{sub m}A{sub 2}O{sub m+2}]{sub q}CoO{sub 2}, the parent m=0 phases exhibit divergent chemical features but are less understood than the more common m>0 members of the series. Here we synthesize Sr-for-Ca substituted [(Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2}]{sub q}CoO{sub 2} zero phases up to x=0.2 through low-temperature hydrothermal conversion of precursor powders of the m=1 misfit system, [Co(Ca{sub 1?x}Sr{sub x}){sub 2}O{sub 3}]{sub q}CoO{sub 2}. In the zero-phase [(Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2}]{sub q}CoO{sub 2} system, as the Sr content x increases the lattice expands anisotropically along the c axis such that the ab-plane dimension and the misfit parameter q remain essentially constant. X-ray absorption spectroscopy data suggest the presence of peroxide-type oxygen species in the (Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2} rock-salt block and together with infrared spectroscopy, thermogravimetric and low-temperature resistivity and thermopower measurements evidence that the isovalent Sr-for-Ca substitution controls the balance between the peroxide and hydroxide species in the (Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2} block but leaves the valence of Co essentially intact in the CoO{sub 2} block. The higher electrical conductivity of the Sr-substituted phases is explained as a consequence of increased carrier mobility. - Graphical abstract: Among the thermoelectric misfit-layered cobalt oxides, [M{sub m}A{sub 2}O{sub m+2}]{sub q}CoO{sub 2}, the parent zero (m=0) phases exhibit divergent chemical features. For [(Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2}]{sub q}CoO{sub 2}, X-ray absorption spectroscopy data suggest the presence of peroxide-type oxygen species in the (Ca{sub 1?x}Sr{sub x}){sub z}(O,OH){sub 2} rock-salt block and together with thermogravimetric and low-temperature transport-property measurements evidence that the isovalent Sr-for-Ca substitution controls the balance between the

  10. Oxygen-induced Y surface segregation in a CuPdY ternary alloy

    SciTech Connect (OSTI)

    Tafen, D. N.; Miller, J. B.; Dogan, O. N.; Baltrus, J. P.; Kondratyuk, P.

    2013-01-01

    We present a comprehensive theoretical and experimental study of the segregation behavior of the ternary alloy CuPdY in vacuum (i.e., the clean surface) and in the presence of oxygen. Theoretical prediction shows that for clean surface, yttrium will substitute first for Cu and then for Pd at the subsurface lattice site before segregating to the surface where it substitutes for Cu. XRD characterization of the surface of CuPdY indicates the presence of two major phases, B2 CuPd and Pd{sub 3}Y. In the presence of adsorbed oxygen, theory predicts that Y preferentially occupies surface sites due to its stronger oxygen affinity compared to Cu and Pd. XPS experiments confirm the computational results in the adsorbed oxygen case, showing that surface segregation of yttrium is induced by the formation of Y-oxides at the top-surface of the alloy.

  11. Method of controlled reduction of nitroaromatics by enzymatic reaction with oxygen sensitive nitroreductase enzymes

    DOE Patents [OSTI]

    Shah, Manish M.; Campbell, James A.

    1998-01-01

    A method for the controlled reduction of nitroaromatic compounds such as nitrobenzene and 2,4,6-trinitrotoluene by enzymatic reaction with oxygen sensitive nitroreductase enzymes, such as ferredoxin NADP oxidoreductase.

  12. Ion implantation method for preparing polymers having oxygen erosion resistant surfaces

    DOE Patents [OSTI]

    Lee, E.H.; Mansur, L.K.; Heatherly, L. Jr.

    1995-04-18

    Hard surfaced polymers and the method for making them are generally described. Polymers are subjected to simultaneous multiple ion beam bombardment, that results in a hardening of the surface, improved wear resistance, and improved oxygen erosion resistance. 8 figs.

  13. Ion implantation method for preparing polymers having oxygen erosion resistant surfaces

    DOE Patents [OSTI]

    Lee, Eal H.; Mansur, Louis K.; Heatherly, Jr., Lee

    1995-01-01

    Hard surfaced polymers and the method for making them are generally described. Polymers are subjected to simultaneous multiple ion beam bombardment, that results in a hardening of the surface, improved wear resistance, and improved oxygen erosion resistance.

  14. Improving the System Life of Basic Oxygen and Electric Arc Furnace Hoods, Roofs, and Side Vents

    Broader source: Energy.gov [DOE]

    This factsheet describes the benefits of a high-performance aluminum bronze alloy to basic oxygen furnace and electric arc furnace components such as hoods, roofs, and side vents.

  15. Quantitative analysis of oxygen content in copper oxide films using ultra microbalance

    SciTech Connect (OSTI)

    Shu, Yonghua; Wang, Lianhong; Liu, Chong; Fan, Jing

    2014-12-09

    Copper oxide films were prepared on quartz substrates through electron beam physical vapor deposition in a vacuum chamber, and the films were observed using X-ray diffraction (XRD) and scanning electron microscope (SEM). The oxygen content of the films were analyzed using an ultra microbalance. Results indicated that when the substrate was heated to 600°C and the oxygen flow rate was 5 sccm, the film was composed of 47% Cu and 53% Cu2O (mass percent), and the oxidation ratio of copper was 25%. After the deposition process at the same condition, i.e. the substrate at temperature of 600°C and blowed by oxygen flowrate of 5 sccm, then in-stu annealed at 600°C in low oxygen pressure of 10 Pa for 30 minutes, the film composition became 22% Cu2O and 78% CuO (mass percent), and the oxidation ratio of copper greatly increased to about 88%.

  16. Melting in the Iron-Oxygen-Silicon System up to 85 GPa. (Journal...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Melting in the Iron-Oxygen-Silicon System up to 85 GPa. Citation Details ... Country of Publication: United States Language: English Word Cloud More Like This Full ...

  17. Melting in the Iron-Oxygen-Silicon System up to 85 GPa. (Journal...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Melting in the Iron-Oxygen-Silicon System ... Country of Publication: United States Language: English Word Cloud More Like This Full ...

  18. A study on a voloxidizer with an oxygen concentration controller for a scale-up DESIGN

    SciTech Connect (OSTI)

    Kim, Young-Hwan; Yoon, Ji-Sup; Park, Byung-Suk; Jung, Jae-Hoo

    2007-07-01

    For a oxidation of UO{sub 2} pellets of tens/kg in a vol-oxidizer, the existing devices take a long time, also, for their scale-up to an engineering scale, we need the optimum oxygen concentration with an maximum oxidation efficiency. In this study, we attained the optimum oxygen concentration to shorten the oxidation time of a simulation fuel using a vol-oxidizer with an oxygen concentration controller and sensor. We compared the characteristics of a galvanic sensor with a zirconium oxide (ZrO{sub 2}) one. The simulation fuel was manufactured with 14 metallic oxides, and used at a mass of 500 g HM/batch. At 500 deg. C, the galvanic and zirconium oxide sensors measured the oxidation time for the simulation fuel. Also, the oxidation time of the simulation fuel was measured according to a change of the oxygen concentration with the selected sensor, and the sample was analyzed. (authors)

  19. Direct method gas-phase oxygen abundances of four Lyman break analogs

    SciTech Connect (OSTI)

    Brown, Jonathan S.; Croxall, Kevin V.; Pogge, Richard W.

    2014-09-10

    We measure the gas-phase oxygen abundances in four Lyman break analogs using auroral emission lines to derive direct abundances. The direct method oxygen abundances of these objects are generally consistent with the empirically derived strong-line method values, confirming that these objects are low oxygen abundance outliers from the mass-metallicity (MZ) relation defined by star forming Sloan Digital Sky Survey galaxies. We find slightly anomalous excitation conditions (Wolf-Rayet features) that could potentially bias the empirical estimates toward high values if caution is not exercised in the selection of the strong-line calibration. The high rate of star formation and low oxygen abundance of these objects is consistent with the predictions of the fundamental metallicity relation, in which the infall of relatively unenriched gas simultaneously triggers an episode of star formation and dilutes the interstellar medium of the host galaxy.

  20. Method of controlled reduction of nitroaromatics by enzymatic reaction with oxygen sensitive nitroreductase enzymes

    DOE Patents [OSTI]

    Shah, M.M.; Campbell, J.A.

    1998-07-07

    A method is described for the controlled reduction of nitroaromatic compounds such as nitrobenzene and 2,4,6-trinitrotoluene by enzymatic reaction with oxygen sensitive nitroreductase enzymes, such as ferredoxin NADP oxidoreductase. 6 figs.

  1. Potential hydrogen and oxygen partial pressures in legacy plutonium oxide packages at Oak Ridge

    SciTech Connect (OSTI)

    Veirs, Douglas K.

    2014-07-07

    An approach to estimate the maximum hydrogen and oxygen partial pressures within sealed containers is described and applied to a set of packages containing high-purity plutonium dioxide. The approach uses experimentally determined maximum hydrogen and oxygen partial pressures and scales the experimentally determined pressures to the relevant packaged material properties. The important material properties are the specific wattage and specific surface area (SSA). Important results from the experimental determination of maximum partial pressures are (1) the ratio of hydrogen to oxygen is stoichiometric, and (2) the maximum pressures increase with increasing initial rates of production. The material properties that influence the rates are the material specific wattage and the SSA. The unusual properties of these materials, high specific wattage and high SSA, result in higher predicted maximum pressures than typical plutonium dioxide in storage. The pressures are well within the deflagration range for mixtures of hydrogen and oxygen.

  2. From Fjords to Open Seas: Ecological Genomics of Expanding Oxygen Minimum Zones (2010 JGI User Meeting)

    ScienceCinema (OSTI)

    Hallam, Steven

    2011-04-26

    Steven Hallam of the University of British Columbia talks "From Fjords to Open Seas: Ecological Genomics of Expanding Oxygen Minimum Zones" on March 24, 2010 at the 5th Annual DOE JGI User Meeting

  3. Table 10. U.S. Refiner Oxygenated Motor Gasoline Prices by...

    U.S. Energy Information Administration (EIA) Indexed Site

    98.0 98.0 86.6 75.0 - 80.1 See footnotes at end of table. 10. U.S. Refiner Oxygenated Motor Gasoline Prices by Grade and Sales Type 20 Energy Information Administration ...

  4. Table 10. U.S. Refiner Oxygenated Motor Gasoline Prices by...

    U.S. Energy Information Administration (EIA) Indexed Site

    94.0 93.9 83.2 73.8 - 79.3 See footnotes at end of table. 10. U.S. Refiner Oxygenated Motor Gasoline Prices by Grade and Sales Type 20 Energy Information Administration ...

  5. Application of oxygen-enriched combustion for locomotive diesel engines. Phase 1

    SciTech Connect (OSTI)

    Poola, R.B.; Sekar, R.R.; Assanis, D.N.

    1996-09-01

    A thermodynamic simulation is used to study the effects of oxygen-enriched intake air on the performance and nitrogen oxide (NO) emissions of a locomotive diesel engine. The parasitic power of the air separation membrane required to supply the oxygen-enriched air is also estimated. For a given constraint on peak cylinder pressure, the gross and net power outputs of an engine operating under different levels of oxygen enrichment are compared with those obtained when a high-boost turbocharged engine is used. A 4% increase in peak cylinder pressure can result in an increase in net engine power of approximately 13% when intake air with an oxygen content of 28% by volume is used and fuel injection timing is retarded by 4 degrees. When the engine is turbocharged to a higher inlet boost, the same increase in peak cylinder pressure improves power by only 4%. If part of the significantly higher exhaust enthalpies available as a result of oxygen enrichment are recovered, the power requirements of the air separator membrane can be met, resulting in substantial net power improvements. Oxygen enrichment reduces particulate and visible smoke emissions but increases NO emissions. However, a combination of retarded fuel injection timing and post-treatment of exhaust gases may be adequate to meet the locomotive diesel engine NO{sub x} standards. Exhaust gas after-treatment and heat recovery would be required to realize the full potential of oxygen enrichment. Economic analysis shows that oxygen-enrichment technology is economically feasible and provides high returns on investment. The study also indicates the strong influence of membrane parasitic requirements and exhaust energy recovery on economic benefits. To obtain an economic advantage while using a membrane with higher parasitic power requirements, it is necessary to recover a part of the exhaust energy.

  6. Mass-selected Nanoparticles of PtxY as Model Catalysts for Oxygen

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electroreduction | Stanford Synchrotron Radiation Lightsource Mass-selected Nanoparticles of PtxY as Model Catalysts for Oxygen Electroreduction Thursday, July 31, 2014 A team of researchers from the Technical University of Denmark and the SUNCAT Institute at the SLAC National Accelerator Laboratory and Stanford University has demonstrated the superior performance of nanoparticles of platinum-yttrium (PtxY) as catalysts for oxygen electroreduction. Polymer electrolyte membrane fuel cells

  7. Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates

    DOE Patents [OSTI]

    Adzic, Radoslav; Zhang, Junliang; Vukmirovic, Miomir

    2011-11-22

    The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

  8. Selective reduction of NOx in oxygen rich environments with plasma-assisted

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    catalysis: Catalyst development and mechanistic studies | Department of Energy reduction of NOx in oxygen rich environments with plasma-assisted catalysis: Catalyst development and mechanistic studies Selective reduction of NOx in oxygen rich environments with plasma-assisted catalysis: Catalyst development and mechanistic studies 2003 DEER Conference Presentation: Pacific Northwest National Laboratory 2003_deer_peden.pdf (867.07 KB) More Documents & Publications Plasma-Activated Lean

  9. Discovery of oxygen in atmosphere could mean life for Saturn's moon Dione

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Discovery of oxygen in atmosphere could mean life for Saturn's moon Dione Discovery of oxygen in atmosphere could mean life for Saturn's moon Dione Discovery could mean ingredients for life are abundant on icy space bodies. March 5, 2012 Curiosity rover bears three LANL technologies Inside Titan: This artist's concept shows a possible scenario for the internal structure of Titan, as suggested by data from NASA's Cassini spacecraft. Scientists have been trying to determine what is under Titan's

  10. Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates

    DOE Patents [OSTI]

    Adzic, Radoslav; Zhang, Junliang; Vukmirovic, Miomir

    2012-11-13

    The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

  11. Device and method for determining oxygen concentration and pressure in gases

    DOE Patents [OSTI]

    Ayers, Michael R. (El Cerrito, CA); Hunt, Arlon J. (Kensington, CA)

    1999-01-01

    Disclosed are oxygen concentration and/or pressure sensing devices and methods which incorporate photoluminescent silica aerogels. Disclosed sensors include a light proof housing for holding the photoluminescent aerogel, a source of excitation radiation (e.g., a UV source), a detector for detecting radiation emitted by the aerogel, a system for delivering a sample gas to the aerogel, and a thermocouple. Also disclosed are water resistant oxygen sensors having a photoluminescent aerogel coated with a hydrophobic material.

  12. Device and method for determining oxygen concentration and pressure in gases

    DOE Patents [OSTI]

    Ayers, M.R.; Hunt, A.J.

    1999-03-23

    Disclosed are oxygen concentration and/or pressure sensing devices and methods which incorporate photoluminescent silica aerogels. Disclosed sensors include a light proof housing for holding the photoluminescent aerogel, a source of excitation radiation (e.g., a UV source), a detector for detecting radiation emitted by the aerogel, a system for delivering a sample gas to the aerogel, and a thermocouple. Also disclosed are water resistant oxygen sensors having a photoluminescent aerogel coated with a hydrophobic material. 6 figs.

  13. Oxygen Transport Kinetics in Infiltrated SOFCs Cathode by Electrical Conductivity Relaxation Technique

    SciTech Connect (OSTI)

    Li, Yihong; Gerdes, Kirk; Liu, Xingbo

    2013-07-01

    Infiltration has attracted increasing attention as an effective technique to modify SOFC cathodes to improve cell electrochemical performance while maintaining material compatibility and long-term stability. However, the infiltrated material's effect on oxygen transport is still not clear and detailed knowledge of the oxygen reduction reaction in infiltrated cathodes is lacking. In this work, the technique of electrical conductivity relaxation (ECR) is used to evaluate oxygen exchange in two common infiltrated materials, Ce{sub 0.8}Sm{sub 0.2}O{sub 1.9} and La{sub 0.6}Sr{sub 0.4}CoO{sub 3-?}. The ECR technique is also used to examine the transport processes in a composite material formed with a backbone of La{sub 0.6}Sr{sub 0.4}Co{sub 0.2}Fe{sub 0.8}O{sub 3-?} and possessing a thin, dense surface layer composed of the representative infiltrate material. Both the surface oxygen exchange process and the oxygen exchange coefficient at infiltrate/LSCF interface are reported. ECR testing results indicate that the application of infiltrate under certain oxygen partial pressure conditions produces a measureable increase in the fitted oxygen exchange parameter. It is presently only possible to generate hypotheses to explain the observation. However the correlation between improved electrochemical performance and increased oxygen transport measured by ECR is reliably demonstrated. The simple and inexpensive ECR technique is utilized as a direct method to optimize the selection of specific infiltrate/backbone material systems for superior performance.

  14. Process for the conversion of alcohols and oxygenates to hydrocarbons in a turbulent fluid bed reactor

    SciTech Connect (OSTI)

    Avidan, A. A.; Kam, A. Y.

    1985-04-23

    Improvements in converting C/sub 1/-C/sub 3/ monohydric alcohols, particularly methanol, related oxygenates of said alcohols and/or oxygenates produced by Fischer-Tropsch synthesis to light olefins, gasoline boiling range hydrocarbons and/or distillate boiling range hydrocarbons are obtained in a fluidized bed of ZSM-5 type zeolite catalyst operating under conditions effective to provide fluidization in the turbulent regime.

  15. Mobilization of Metals from Eau Claire Siltstone and the Impact of Oxygen under Geological Carbon Dioxide Sequestration Conditions

    SciTech Connect (OSTI)

    Shao, Hongbo; Kukkadapu, Ravi K.; Krogstad, Eirik J.; Newburn, Matthew K.; Cantrell, Kirk J.

    2014-09-01

    , the mobilization of Pb, Cd, and Cu was significantly enhanced, whereas As concentrations decreased, compared with the reaction system without oxygen. The presence of oxygen resulted in the formation of secondary Fe-oxides which appear to be Fe(II)-substituted P-containing ferrihydrite. Although the rock contained only 1.04 wt% total Fe, oxidative dissolution of pyrite, leaching and oxidation of structural Fe(II) in fluorapatite, and precipitation of Fe-oxides significantly decreased the pH in brine with oxygen(pH 3.3-3.7), compared with the reaction system without oxygen (pH 4.2-4.4). In the CO2-rock-brine system without O2, the majority of As remained in the rock, with about 1.1% of the total As being released from intrinsic Fe-oxides to the aqueous phase. The release behavior of As to solution was consistent with competitive adsorption between phosphate/fluoride and As on Fe-oxide surfaces. In the presence of O2 the mobility of As was reduced due to enhanced adsorption onto both intrinsic and secondary Fe-oxide surfaces.When O2 was present, the dominant species in solution was the less toxic As(V). This work will advance our understanding of the geochemical reaction mechanisms that occur under GCS conditions and help to evaluate the risks associated with geological CO2 sequestration.

  16. Effect of cation ordering on oxygen vacancy diffusion pathways in double perovskites

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Uberuaga, Blas Pedro; Pilania, Ghanshyam

    2015-07-08

    Perovskite structured oxides (ABO3) are attractive for a number of technological applications, including as superionics because of the high oxygen conductivities they exhibit. Double perovskites (AA’BB’O6) provide even more flexibility for tailoring properties. Using accelerated molecular dynamics, we examine the role of cation ordering on oxygen vacancy mobility in one model double perovskite SrLaTiAlO6. We find that the mobility of the vacancy is very sensitive to the cation ordering, with a migration energy that varies from 0.6 to 2.7 eV. In the extreme cases, the mobility is both higher and lower than either of the two end member single perovskites.more » Further, the nature of oxygen vacancy diffusion, whether one-dimensional, two-dimensional, or three-dimensional, also varies with cation ordering. We correlate the dependence of oxygen mobility on cation structure to the distribution of Ti4+ cations, which provide unfavorable environments for the positively charged oxygen vacancy. The results demonstrate the potential of using tailored double perovskite structures to precisely control the behavior of oxygen vacancies in these materials.« less

  17. Oxygen Atom Adsorption on and Diffusion into Nb(110) and Nb(100) from First Principles

    SciTech Connect (OSTI)

    Tafen, De Nyago; Gao, Michael C.

    2013-11-01

    In order to understand the dynamics of oxidation of Nb, we examine the adsorption, absorption, and diffusion of an oxygen atom on, in, and into Nb(110) and Nb(100) surfaces, respectively, using density functional theory. Our calculations predict that the oxygen atom adsorbs on the threefold site on Nb(110) and the fourfold hollow site on Nb(100), and the adsorption energy is -5.08 and -5.18 eV respectively. We find the long and short bridge sites to be transition states for O diffusion on Nb(110), while the on top site is a rank-2 saddle point. In the subsurface region, the oxygen atom prefers the octahedral site, as in bulk niobium. Our results also show that the O atom is more stable on Nb(110) subsurface than on Nb(100) subsurface. The diffusion of oxygen atoms into niobium surfaces passes through transition states where the oxygen atom is coordinated to four niobium atoms. The diffusion barriers of the oxygen atom into Nb(110) and Nb(100) are 1.81 and 2.05 eV, respectively. Analysis of the electronic density of states reveals the emergence of well localized electronic states below the lowest states of clean Nb surfaces due to d-p orbital hybridization.

  18. Absolute atomic oxygen and nitrogen densities in radio-frequency driven atmospheric pressure cold plasmas: Synchrotron vacuum ultra-violet high-resolution Fourier-transform absorption measurements

    SciTech Connect (OSTI)

    Niemi, K.; O'Connell, D.; Gans, T.; Oliveira, N. de; Joyeux, D.; Nahon, L.; Booth, J. P.

    2013-07-15

    Reactive atomic species play a key role in emerging cold atmospheric pressure plasma applications, in particular, in plasma medicine. Absolute densities of atomic oxygen and atomic nitrogen were measured in a radio-frequency driven non-equilibrium plasma operated at atmospheric pressure using vacuum ultra-violet (VUV) absorption spectroscopy. The experiment was conducted on the DESIRS synchrotron beamline using a unique VUV Fourier-transform spectrometer. Measurements were carried out in plasmas operated in helium with air-like N{sub 2}/O{sub 2} (4:1) admixtures. A maximum in the O-atom concentration of (9.1 {+-} 0.7) Multiplication-Sign 10{sup 20} m{sup -3} was found at admixtures of 0.35 vol. %, while the N-atom concentration exhibits a maximum of (5.7 {+-} 0.4) Multiplication-Sign 10{sup 19} m{sup -3} at 0.1 vol. %.

  19. Differentiating the role of lithium and oxygen in retaining deuterium on lithiated graphite plasma-facing components

    SciTech Connect (OSTI)

    C.N. Taylor; J. P. Allain; P. S. Krstic; J. Dadras; C. H. Skinner; K. E. Luitjohan

    2013-11-01

    Laboratory experiments have been used to investigate the fundamental interactions responsible for deuterium retention in lithiated graphite. Oxygen was found to be present and play a key role in experiments that simulated NSTX lithium conditioning, where the atomic surface concentration can increase to >40% when deuterium retention chemistry is observed. Quantum-classical molecular dynamic simulations elucidated this oxygen-deuterium effect and showed that oxygen retains significantly more deuterium than lithium in a simulated matrix with 20% lithium, 20% oxygen, and 60% carbon. Simulations further show that deuterium retention is even higher when lithium is removed from the matrix. Experiments artificially increased the oxygen content in graphite to approximately 16% and then bombarded with deuterium. XPS showed depletion of the oxygen and no enhanced deuterium retention, thus demonstrating that lithium is essential in retaining the oxygen that thereby retains deuterium.

  20. Differentiating the role of lithium and oxygen in retaining deuterium on lithiated graphite plasma-facing components

    SciTech Connect (OSTI)

    Taylor, C. N. [Fusion Safety Program, Idaho National Laboratory, P.O. Box 1625-7113, Idaho Falls, Idaho 83415 (United States) [Fusion Safety Program, Idaho National Laboratory, P.O. Box 1625-7113, Idaho Falls, Idaho 83415 (United States); School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Allain, J. P. [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States) [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, Illinois 61801 (United States); Luitjohan, K. E. [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States)] [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Krstic, P. S. [Institute for Advanced Computational Science, Stony Brook University, New York 11794 (United States) [Institute for Advanced Computational Science, Stony Brook University, New York 11794 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); TheoretiK, Knoxville, Tennessee 379XX (United States); Dadras, J. [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States) [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095 (United States); Skinner, C. H. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-05-15

    Laboratory experiments have been used to investigate the fundamental interactions responsible for deuterium retention in lithiated graphite. Oxygen was found to be present and play a key role in experiments that simulated NSTX lithium conditioning, where the atomic surface concentration can increase to >40% when deuterium retention chemistry is observed. Quantum-classical molecular dynamic simulations elucidated this oxygen-deuterium effect and showed that oxygen retains significantly more deuterium than lithium in a simulated matrix with 20% lithium, 20% oxygen, and 60% carbon. Simulations further show that deuterium retention is even higher when lithium is removed from the matrix. Experiments artificially increased the oxygen content in graphite to ?16% and then bombarded with deuterium. X-ray photoelectron spectroscopy showed depletion of the oxygen and no enhanced deuterium retention, thus demonstrating that lithium is essential in retaining the oxygen that thereby retains deuterium.

  1. Oregon State Endangered Species List | Open Energy Information

    Open Energy Info (EERE)

    to library Web Site: Oregon State Endangered Species List Author Oregon Department of Fish and Wildlife Published State of Oregon, Date Not Provided DOI Not Provided Check for...

  2. Washington State Species of Concern Lists | Open Energy Information

    Open Energy Info (EERE)

    Web Site: Washington State Species of Concern Lists Author Washington Department of Fish & Wildlife Published State of Washington, Date Not Provided DOI Not Provided Check for...

  3. BLM - Western BLM Bird Species of Conservation Concern List ...

    Open Energy Info (EERE)

    BLM - Western BLM Bird Species of Conservation Concern List Jump to: navigation, search OpenEI Reference LibraryAdd to library PermittingRegulatory Guidance - Checklist: BLM -...

  4. Mixed species radioiodine air sampling readout and dose assessment system

    DOE Patents [OSTI]

    Distenfeld, Carl H.; Klemish, Jr., Joseph R.

    1978-01-01

    This invention provides a simple, reliable, inexpensive and portable means and method for determining the thyroid dose rate of mixed airborne species of solid and gaseous radioiodine without requiring highly skilled personnel, such as health physicists or electronics technicians. To this end, this invention provides a means and method for sampling a gas from a source of a mixed species of solid and gaseous radioiodine for collection of the mixed species and readout and assessment of the emissions therefrom by cylindrically, concentrically and annularly molding the respective species around a cylindrical passage for receiving a conventional probe-type Geiger-Mueller radiation detector.

  5. FERC Hydropower Licensing and Endangered Species - A Guide for...

    Open Energy Info (EERE)

    FERC Hydropower Licensing and Endangered Species - A Guide for Applicants, Contractors, and Staff Jump to: navigation, search OpenEI Reference LibraryAdd to library Permitting...

  6. Hydropower Licensing and Endangered Species A Guide for Applicants...

    Open Energy Info (EERE)

    Hydropower Licensing and Endangered Species A Guide for Applicants, Contractors, and Staff Jump to: navigation, search OpenEI Reference LibraryAdd to library General: Hydropower...

  7. An Investigation of the Ionic Conductivity and Species Crossover...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the active species across the membrane. (c ) The performance of Li-N117 ... Scientific Achievement Solvent volume fraction within the membrane has the greatest effect ...

  8. Washington Priority Habitats and Species on the Web | Open Energy...

    Open Energy Info (EERE)

    Habitats and Species (PHS) in Washington State. PHS is a source of best available science that can inform local planning activities, development projects, conservation...

  9. Comparing Patterns of Natural Selection across Species Using...

    Office of Scientific and Technical Information (OSTI)

    background rates for 744 core protein families in 30 c-proteobacterial species. ... For example,glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina ...

  10. AISI/DOE Technology Roadmap Program Hot Oxygen Injection Into The Blast Furnace

    SciTech Connect (OSTI)

    Michael F. Riley

    2002-10-21

    Increased levels of blast furnace coal injection are needed to further lower coke requirements and provide more flexibility in furnace productivity. The direct injection of high temperature oxygen with coal in the blast furnace blowpipe and tuyere offers better coal dispersion at high local oxygen concentrations, optimizing the use of oxygen in the blast furnace. Based on pilot scale tests, coal injection can be increased by 75 pounds per ton of hot metal (lb/thm), yielding net savings of $0.84/tm. Potential productivity increases of 15 percent would yield another $1.95/thm. In this project, commercial-scale hot oxygen injection from a ''thermal nozzle'' system, patented by Praxair, Inc., has been developed, integrated into, and demonstrated on two tuyeres of the U.S. Steel Gary Works no. 6 blast furnace. The goals were to evaluate heat load on furnace components from hot oxygen injection, demonstrate a safe and reliable lance and flow control design, and qualitatively observe hot oxygen-coal interaction. All three goals have been successfully met. Heat load on the blowpipe is essentially unchanged with hot oxygen. Total heat load on the tuyere increases about 10% and heat load on the tuyere tip increases about 50%. Bosh temperatures remained within the usual operating range. Performance in all these areas is acceptable. Lance performance was improved during testing by changes to lance materials and operating practices. The lance fuel tip was changed from copper to a nickel alloy to eliminate oxidation problems that severely limited tip life. Ignition flow rates and oxygen-fuel ratios were changed to counter the effects of blowpipe pressure fluctuations caused by natural resonance and by coal/coke combustion in the tuyere and raceway. Lances can now be reliably ignited using the hot blast as the ignition source. Blowpipe pressures were analyzed to evaluate ht oxygen-coal interactions. The data suggest that hot oxygen increases coal combustion in the blow pipe and

  11. Effects of Headspace and Oxygen Level on Off-gas Emissions from Wood Pellets in Storage

    SciTech Connect (OSTI)

    Sokhansanj, Shahabaddine; Kuang, Xingya; Shankar, T.S.; Lim, C. Jim; Bi, X.T.; Melin, Staffan

    2009-10-01

    Few papers have been published in the open literature on the emissions from biomass fuels, including wood pellets, during the storage and transportation and their potential health impacts. The purpose of this study is to provide data on the concentrations, emission factors, and emission rate factors of CO2, CO, and CH4 from wood pellets stored with different headspace to container volume ratios with different initial oxygen levels, in order to develop methods to reduce the toxic off-gas emissions and accumulation in storage spaces. Metal containers (45 l, 305 mm diameter by 610 mm long) were used to study the effect of headspace and oxygen levels on the off-gas emissions from wood pellets. Concentrations of CO2, CO, and CH4 in the headspace were measured using a gas chromatograph as a function of storage time. The results showed that the ratio of the headspace ratios and initial oxygen levels in the storage space significantly affected the off-gas emissions from wood pellets stored in a sealed container. Higher peak emission factors and higher emission rates are associated with higher headspace ratios. Lower emissions of CO2 and CO were generated at room temperature under lower oxygen levels, whereas CH4 emission is insensitive to the oxygen level. Replacing oxygen with inert gases in the storage space is thus a potentially effective method to reduce the biomass degradation and toxic off-gas emissions. The proper ventilation of the storage space can also be used to maintain a high oxygen level and low concentrations of toxic off-gassing compounds in the storage space, which is especially useful during the loading and unloading operations to control the hazards associated with the storage and transportation of wood pellets.

  12. Conversion of Mixed Oxygenates Generated from Synthesis Gas to Fuel Range Hydrocarbon

    SciTech Connect (OSTI)

    Ramasamy, Karthikeyan K.; Gerber, Mark A.; Lilga, Michael A.; Flake, Matthew D.

    2012-08-19

    The growing dependence in the U.S. on foreign crude oil supplies and increased concerns regarding greenhouse gas emission has generated considerable interest in research to develop renewable and environmentally friendly liquid hydrocarbon transportation fuels. One of the strategies for achieving this is to produce intermediate compounds such as alcohols and other simple oxygenates from biomass generated synthesis gas (mixture of carbon monoxide and hydrogen) and further convert them into liquid hydrocarbons. The focus of this research is to investigate the effects of mixed oxygenates intermediate product compositions on the conversion step to produce hydrocarbon liquids. A typical mixed oxygenate stream is expected to contain water (around 50%), alcohols, such as methanol and ethanol (around 35%), and smaller quantities of oxygenates such as acetaldehyde, acetic acid and ethyl acetate. However the ratio and the composition of the mixed oxygenate stream generated from synthesis gas vary significantly depending on the catalyst used and the process conditions. Zeolite catalyzed deoxygenation of methanol accompanied by chain growth is well understood under Methanol-to-Gasoline (MTG) like reaction conditions using an H-ZSM-5 zeolite as the catalyst6-8. Research has also been conducted to a limited extent in the past with higher alcohols, but not with other oxygenates present9-11. Also there has been little experimental investigation into mixtures containing substantial amounts of water. The latter is of particular interest because water separation from the hydrocarbon product would be less energy intensive than first removing it from the oxygenate intermediate stream prior to hydrocarbon synthesis, potentially reducing overall processing costs.

  13. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest): Coho salmon. [Oncorhynchus kisutch

    SciTech Connect (OSTI)

    Hassler, T.J.

    1987-08-01

    This species profile summarizes taxonomy, morphology, distribution, abundance, life history, and environmental requirements of coho salmon in the Pacific Southwest (California). Coho salmon are anadromous and enter freshwater in fall to spawn, after liver in the ocean for two growing seasons. Spawning peaks in November to January. The fry hatch in spring and migrate to the ocean in about a year. Juvenile coho require a mixture of pools and riffles, abundant instream and bank cover, water temperatures of 10 to 15/sup 0/C in summer, dissolved oxygen near saturation, and riffles with relatively little sediment and with abundant aquatic and terrestrial insects for food. Coho salmon support an extensive commercial and sport fishery. Habitats that support coho salmon are continually being destroyed or degraded; state, federal, and private agencies are working to restore and enhance these habitats.

  14. Proceedings of the Subcontractors' Review Meeting: Aquatic Species Program

    SciTech Connect (OSTI)

    Not Available

    1981-07-01

    The Aquatic Species Program (ASP) addresses the utilization of plant biomass that naturally occurs in wetland or submerged areas. Processes are being developed through this program to make use of such aquatic species, capitalizing on their inherent capacity for rapid growth as well as their extraordinary chemical compositions.

  15. Preservation of high glycolytic phenotype by establishing new acute lymphoblastic leukemia cell lines at physiologic oxygen concentration

    SciTech Connect (OSTI)

    Sheard, Michael A.; Ghent, Matthew V.; Cabral, Daniel J.; Lee, Joanne C.; Khankaldyyan, Vazgen; Ji, Lingyun; Wu, Samuel Q.; Kang, Min H.; and others

    2015-05-15

    Cancer cells typically exhibit increased glycolysis and decreased mitochondrial oxidative phosphorylation, and they continue to exhibit some elevation in glycolysis even under aerobic conditions. However, it is unclear whether cancer cell lines employ a high level of glycolysis comparable to that of the original cancers from which they were derived, even if their culture conditions are changed to physiologically relevant oxygen concentrations. From three childhood acute lymphoblastic leukemia (ALL) patients we established three new pairs of cell lines in both atmospheric (20%) and physiologic (bone marrow level, 5%) oxygen concentrations. Cell lines established in 20% oxygen exhibited lower proliferation, survival, expression of glycolysis genes, glucose consumption, and lactate production. Interestingly, the effects of oxygen concentration used during cell line initiation were only partially reversible when established cell cultures were switched from one oxygen concentration to another for eight weeks. These observations indicate that ALL cell lines established at atmospheric oxygen concentration can exhibit relatively low levels of glycolysis and these levels are semi-permanent, suggesting that physiologic oxygen concentrations may be needed from the time of cell line initiation to preserve the high level of glycolysis commonly exhibited by leukemias in vivo. - Highlights: • Establishing new ALL cell lines in 5% oxygen resulted in higher glycolytic expression and function. • Establishing new ALL cell lines in 5% oxygen resulted in higher proliferation and lower cell death. • The divergent metabolic phenotypes selected in 5% and 20% oxygen are semi-permanent.

  16. Thomson scattering diagnostic for the measurement of ion species fraction

    SciTech Connect (OSTI)

    Ross, J S; Park, H S; Amendt, A; Divol, L; Kugland, N L; Rozmus, W; Glenzer, S H

    2012-05-01

    Simultaneous Thomson scattering measurements of collective electron-plasma and ion-acoustic fluctuations have been utilized to determine ion species fraction from laser produced CH plasmas. The CH{sub 2} foil is heated with 10 laser beams, 500 J per beam, at the Omega Laser facility. Thomson scattering measurements are made 4 mm from the foil surface using a 30 J 2{omega} probe laser with a 1 ns pulse length. Using a series of target shots the plasma evolution is measured from 2.5 ns to 9 ns after the rise of the heater beams. Measuring the electron density and temperature from the electron-plasma fluctuations constrains the fit of the two-ion species theoretical form factor for the ion feature such that the ion temperature, plasma flow velocity and ion species fraction are determined. The ion species fraction is determined to an accuracy of {+-}0.06 in species fraction.

  17. Measurement of Species Distributions in Operating Fuel Cells

    SciTech Connect (OSTI)

    Partridge Jr, William P; Toops, Todd J; Parks, II, James E; Armstrong, Timothy R.

    2004-10-01

    Measurement and understanding of transient species distributions across and within fuel cells is a critical need for advancing fuel cell technology. The Spatially Resolved Capillary Inlet Mass Spectrometer (SpaciMS) instrument has been applied for in-situ measurement of transient species distributions within operating reactors; including diesel catalyst, air-exhaust mixing systems, and non-thermal plasma reactors. The work described here demonstrates the applicability of this tool to proton exchange membrane (PEM) and solid oxide fuel cells (SOFC) research. Specifically, we have demonstrated SpaciMS measurements of (1) transient species dynamics across a PEM fuel cell (FC) associated with load switching, (2) intra-PEM species distributions, and transient species dynamics at SOFC temperatures associated with FC load switching.

  18. Method and device for identifying different species of honeybees

    DOE Patents [OSTI]

    Kerr, Howard T.; Buchanan, Michael E.; Valentine, Kenneth H.

    1989-01-01

    A method and device have been provided for distinguishing Africanized honeybees from European honeybees. The method is based on the discovery of a distinct difference in the acoustical signatures of these two species of honeybees in flight. The European honeybee signature has a fundamental power peak in the 210 to 240 Hz range while the Africanized honeybee signature has a fundamental power peak in the 260 to 290 Hz range. The acoustic signal produced by honeybees is analyzed by means of a detecting device to quickly determine the honeybee species through the detection of the presence of frequencies in one of these distinct ranges. The device includes a microphone for acoustical signal detection which feeds the detected signal into a frequency analyzer which is designed to detect the presence of either of the known fundamental wingbeat frequencies unique to the acoustical signatures of these species as an indication of the identity of the species and indicate the species identity on a readout device.

  19. ORIGINS OF NON-MASS-DEPENDENT FRACTIONATION OF EXTRA-TERRESTRIAL OXYGEN

    SciTech Connect (OSTI)

    Barcena, Homar; Connolly, Harold C.

    2012-08-01

    The distribution of oxygen isotopes in meteorites and within the earliest solids that formed in the solar system hints that the precursors of these materials must have undergone a mass-independent process. The mass-independent process is specifically one that fractionates {sup 16}O from {sup 17}O and {sup 18}O. This chemical signature is indicative of non-equilibrium processing, which bear resemblance to some unusual terrestrial phenomenon such as fractionation of ozone in the upper Earth atmosphere. That the mass-independent fractionation of oxygen isotopes is preserved within petrological records presents planetary scientists interesting clues to the events that may have occurred during the formation of the solar system. Currently, there are several hypotheses on the origins of the oxygen isotope distribution within primitive planetary materials, which include both thermal and photochemical models. We present a new model based on a physico-chemical hypothesis for the origin of non-mass-dependent O-isotope distribution in oxygen-bearing extra-terrestrial materials, which originated from the disproportionation of CO in dark molecular clouds to create CO{sub 2} reservoirs. The disproportionation created a reservoir of heavy oxygen isotopes and could have occurred throughout the evolution of the disk. The CO{sub 2} was a carrier of the isotope anomaly in the solar nebula and we propose that non-steady-state mixing of these reservoirs with the early rock-forming materials during their formation corresponds with the birth and evolution of the solar system.

  20. Experiments on oxygen desorption from surface warm seawater under open-cycle ocean thermal energy conversion

    SciTech Connect (OSTI)

    Pesaran, A.A. )

    1992-11-01

    This paper presents the results of scoping deaeration experiments conducted with warm surface seawater under open-cycle ocean thermal energy conversion (OC-OTEC) conditions. Concentrations of dissolved oxygen in seawater at three locations (in the supply water, water leaving the predeaerator, and discharge water from an evaporator) were measured and used to estimate oxygen desorption levels. The results suggest that 7 percent to 60 percent of the dissolved oxygen in the supply water was desorbed from seawater in the predeaerator for pressures ranging from 35 to 9 kPa. Bubble injection in the upcomer increased the oxygen desorption rate by 20 percent to 60 percent. The data also indicated that at typical OC-OTEC evaporator pressures, when flash evaporation in the evaporator occurred, 75 percent to 95 percent of the dissolved oxygen was desorbed overall from the warm seawater. The results were used to find the impact of a single-stage predeaeration scheme on the power to remove noncondensable gases in an OC-OTEC plant.