National Library of Energy BETA

Sample records for oxygen species ros

  1. Mitochondrial reactive oxygen species and cancer

    E-Print Network [OSTI]

    Chandel, Navdeep S

    Mitochondria produce reactive oxygen species (mROS) as a natural by-product of electron transport chain activity. While initial studies focused on the damaging effects of reactive oxygen species, a recent paradigm shift ...

  2. Inhibition of Pyruvate Kinase M2 by Reactive Oxygen Species Contributes to Cellular Antioxidant Responses

    E-Print Network [OSTI]

    Vander Heiden, Matthew G.

    Control of intracellular reactive oxygen species (ROS) concentrations is critical for cancer cell survival. We show that, in human lung cancer cells, acute increases in intracellular concentrations of ROS caused inhibition ...

  3. Alkbh8 Regulates Selenocysteine-Protein Expression to Protect against Reactive Oxygen Species Damage

    E-Print Network [OSTI]

    Endres, Lauren

    Environmental and metabolic sources of reactive oxygen species (ROS) can damage DNA, proteins and lipids to promote disease. Regulation of gene expression can prevent this damage and can include increased transcription, ...

  4. Generation of Reactive Oxygen Species Mediated by 1Hydroxyphenazine, a Virulence Factor of Pseudomonas aeruginosa

    E-Print Network [OSTI]

    Gates, Kent. S.

    Generation of Reactive Oxygen Species Mediated by 1Hydroxyphenazine, a Virulence Factor tool for the detection of ROS generation mediated by 1-HP. These assays provided evidence that 1-HP evidence that 1-HP mediates the generation of intracellular oxidants. Generation of reactive oxygen species

  5. Effects of ethanol and reactive species on Hepatitis C virus

    E-Print Network [OSTI]

    Seronello, Scott E.

    2010-01-01

    polymerase chain reaction; RNS, reactive nitrogen species;oxygen/nitrogen species (ROS/RNS) and decreased antioxidantincrease the levels of ROS/RNS, oxidized thioredoxin, lipid

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

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

    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...

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

    SciTech Connect (OSTI)

    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.

  8. Generation of highly reactive oxygen species by co-adsorption of oxygen and water on metal-supported MgO(100) thinfilms

    E-Print Network [OSTI]

    Song, Zhenjun

    2015-01-01

    The formation of highly reactive oxygen species (ROS) on metal oxide surfaces have attracted considerable interest due to their diverse applications. In this work, we have performed densi-ty-functional theory calculations to investigate the co-adsorption of oxygen and water on ul-trathin MgO(100) films deposited on Mo(100) substrate. We reveal that the molecular oxygen can be stepwise decomposed completely with the assistance of water. Consequently, a series of highly ROS including superoxide, hydroperoxide, hydroxyl and single oxygen adatom are formed on Mo(100) supported MgO(100) thinfilms. The reaction barriers accompanied by the generation of ROS are reported, and the influence of the thickness of MgO(100) films is also discussed. The most promising routes to produce these fascinating species provide valuable information to understand the importance of synergistic effect, namely the substrate, the co-adorbed species, and the film thickness, in multiphase catalyst design.

  9. Lysophosphatidic acid induces reactive oxygen species generation by activating protein kinase C in PC-3 human prostate cancer cells

    SciTech Connect (OSTI)

    Lin, Chu-Cheng; Lin, Chuan-En; Lin, Yueh-Chien [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China)] [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Ju, Tsai-Kai [Instrumentation Center, National Taiwan University, Taipei, Taiwan, ROC (China) [Instrumentation Center, National Taiwan University, Taipei, Taiwan, ROC (China); Technology Commons, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Huang, Yuan-Li [Department of Biotechnology, Asia University, Taichung, Taiwan, ROC (China)] [Department of Biotechnology, Asia University, Taichung, Taiwan, ROC (China); Lee, Ming-Shyue [Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC (China)] [Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC (China); Chen, Jiun-Hong [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China) [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Department of Life Science, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Lee, Hsinyu, E-mail: hsinyu@ntu.edu.tw [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China) [Institute of Zoology, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Department of Life Science, College of Life Science, National Taiwan University, Taipei, Taiwan, ROC (China); Center for Biotechnology, National Taiwan University, Taipei, Taiwan, ROC (China); Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan, ROC (China)

    2013-11-01

    Highlights: •LPA induces ROS generation through LPA{sub 1} and LPA{sub 3}. •LPA induces ROS generation by activating PLC. •PKC? mediates LPA-induced ROS generation. -- Abstract: Prostate cancer is one of the most frequently diagnosed cancers in males, and PC-3 is a cell model popularly used for investigating the behavior of late stage prostate cancer. Lysophosphatidic acid (LPA) is a lysophospholipid that mediates multiple behaviors in cancer cells, such as proliferation, migration and adhesion. We have previously demonstrated that LPA enhances vascular endothelial growth factor (VEGF)-C expression in PC-3 cells by activating the generation of reactive oxygen species (ROS), which is known to be an important mediator in cancer progression. Using flow cytometry, we showed that LPA triggers ROS generation within 10 min and that the generated ROS can be suppressed by pretreatment with the NADPH oxidase (Nox) inhibitor diphenylene iodonium. In addition, transfection with LPA{sub 1} and LPA{sub 3} siRNA efficiently blocked LPA-induced ROS production, suggesting that both receptors are involved in this pathway. Using specific inhibitors and siRNA, phospholipase C (PLC) and protein kinase C (PKC) were also suggested to participate in LPA-induced ROS generation. Overall, we demonstrated that LPA induces ROS generation in PC-3 prostate cancer cells and this is mediated through the PLC/PKC/Nox pathway.

  10. Inhibition of ERK Oscillations by Ionizing Radiation and Reactive Oxygen Species

    SciTech Connect (OSTI)

    Shankaran, Harish; Chrisler, William B.; Sontag, Ryan L.; Weber, Thomas J.

    2010-12-28

    The shuttling of activated protein kinases between the cytoplasm and nucleus is an essential feature of normal growth factor signaling cascades. Here we demonstrate that transforming growth factor alpha (TGF?) induces oscillations in extracellular signal regulated kinase (ERK) cytoplasmic-nuclear translocations in human keratinocytes. TGF?-dependent ERK oscillations mediated through the epidermal growth factor receptor (EGFR) are inhibited by low dose X-irradiation (10?cGy) and low concentrations of hydrogen peroxide (0.32–3.26?µM H2O2) used as a model reactive oxygen species (ROS). A fluorescent indicator dye (H2-DCFDA) was used to measure cellular ROS levels following X-irradiation, 12-O-tetradecanoyl phorbol-13-acetate (TPA) and H2O2. X-irradiation did not generate significant ROS production while 0.32?µM H2O2 and TPA induced significant increases in ROS levels with H2O2? >?TPA. TPA alone induced transactivation of the EGFR but did not induce ERK oscillations. TPA as a cotreatment did not inhibit TGF?-stimulated ERK oscillations but qualitatively altered TGF?-dependent ERK oscillation characteristics (amplitude, time-period). Collectively, these observations demonstrate that TGF?-induced ERK oscillations are inhibited by ionizing radiation/ROS and perturbed by epigenetic carcinogen in human keratinocytes. © 2010 Wiley-Liss, Inc.

  11. Impact of UV light on the plant cell wall, methane emissions and ROS production 

    E-Print Network [OSTI]

    Messenger, David James

    2009-01-01

    This study presents the first attempt to combine the fields of ultraviolet (UV) photobiology, plant cell wall biochemistry, aerobic methane production and reactive oxygen species (ROS) mechanisms to investigate the effect ...

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

    SciTech Connect (OSTI)

    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.

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

    SciTech Connect (OSTI)

    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.

  14. Reactive Oxygen Species Driven Angiogenesis by Inorganic Nanorods

    E-Print Network [OSTI]

    Patra, Chitta Ranjan

    The exact mechanism of angiogenesis by europium hydroxide nanorods was unclear. In this study we have showed that formation of reactive oxygen species (H2O2 and O2·?) is involved in redox signaling pathways during angiogenesis, ...

  15. Superparamagnetic iron oxide nanoparticles as radiosensitizer via enhanced reactive oxygen species formation

    SciTech Connect (OSTI)

    Klein, Stefanie; Sommer, Anja [Department of Chemistry and Pharmacy, Physical Chemistry I and ICMM, Friedrich-Alexander University of Erlangen-Nuremberg, Egerlandstr. 3, D-91058 Erlangen (Germany)] [Department of Chemistry and Pharmacy, Physical Chemistry I and ICMM, Friedrich-Alexander University of Erlangen-Nuremberg, Egerlandstr. 3, D-91058 Erlangen (Germany); Distel, Luitpold V.R. [Department of Radiation Oncology, Friedrich Alexander University Erlangen-Nuremberg, Universitaetsstrasse 27, D-91054 Erlangen (Germany)] [Department of Radiation Oncology, Friedrich Alexander University Erlangen-Nuremberg, Universitaetsstrasse 27, D-91054 Erlangen (Germany); Neuhuber, Winfried [Department of Anatomy, Chair of Anatomy I, Friedrich Alexander University Erlangen-Nuremberg, Krankenhausstr. 9, D-91054 Erlangen (Germany)] [Department of Anatomy, Chair of Anatomy I, Friedrich Alexander University Erlangen-Nuremberg, Krankenhausstr. 9, D-91054 Erlangen (Germany); Kryschi, Carola, E-mail: kryschi@chemie.uni-erlangen.de [Department of Chemistry and Pharmacy, Physical Chemistry I and ICMM, Friedrich-Alexander University of Erlangen-Nuremberg, Egerlandstr. 3, D-91058 Erlangen (Germany)] [Department of Chemistry and Pharmacy, Physical Chemistry I and ICMM, Friedrich-Alexander University of Erlangen-Nuremberg, Egerlandstr. 3, D-91058 Erlangen (Germany)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Ultrasmall citrate-coated SPIONs with {gamma}Fe{sub 2}O{sub 3} and Fe{sub 3}O{sub 4} structure were prepared. Black-Right-Pointing-Pointer SPIONs uptaken by MCF-7 cells increase the ROS production for about 240%. Black-Right-Pointing-Pointer The SPION induced ROS production is due to released iron ions and catalytically active surfaces. Black-Right-Pointing-Pointer Released iron ions and SPION surfaces initiate the Fenton and Haber-Weiss reaction. Black-Right-Pointing-Pointer X-ray irradiation of internalized SPIONs leads to an increase of catalytically active surfaces. -- Abstract: Internalization of citrate-coated and uncoated superparamagnetic iron oxide nanoparticles by human breast cancer (MCF-7) cells was verified by transmission electron microscopy imaging. Cytotoxicity studies employing metabolic and trypan blue assays manifested their excellent biocompatibility. The production of reactive oxygen species in iron oxide nanoparticle loaded MCF-7 cells was explained to originate from both, the release of iron ions and their catalytically active surfaces. Both initiate the Fenton and Haber-Weiss reaction. Additional oxidative stress caused by X-ray irradiation of MCF-7 cells was attributed to the increase of catalytically active iron oxide nanoparticle surfaces.

  16. 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.

  17. 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.

  18. Properties of reactive oxygen species by quantum Monte Carlo

    SciTech Connect (OSTI)

    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.

  19. 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, E-mail: heaven@umich.edu; 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 47–64.5% 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 necessary for placental development and successful pregnancy, further investigation is warranted of the impact of ROS and BDE-47 on trophoblast cytokine responses. - Highlights: • BDE-47 induced ROS overproduction and mitochondrial dysfunction. • BDE-47 stimulated production of proinflammatory cytokines. • Antioxidant treatment reduced BDE-47-stimulated ROS generation and cytokine release.

  20. Role of nitric oxide in neurodegeneration and vulnerability of neuronal cells to nitric oxide metabolites and reactive oxygen species

    E-Print Network [OSTI]

    Bondy, SC; Lahiri, DK; Ghosh, C; Rogers, JT; Greig, NH

    2010-01-01

    hormone · Reactive nitrogen species · RNS · Tissue culture 1reactive nitrogen species (RNS), such as NO, suggest that inDisorders NO and other ROS and RNS exert important roles in

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

    SciTech Connect (OSTI)

    Smietana, Michael J. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States)] [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Arruda, Ellen M. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States) [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 (United States); Program in Macromolecular Science and Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 (United States); Faulkner, John A.; Brooks, Susan V. [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States) [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Larkin, Lisa M., E-mail: llarkin@umich.edu [Biomedical Engineering, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States); Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 (United States)

    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 data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1{sup -/-} mice may represent an appropriate model for studying disease processes in aging bone.

  2. 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.

  3. Comparison of on-line and off-line methods to quantify reactive oxygen species (ROS) in atmospheric aerosols

    E-Print Network [OSTI]

    Fuller, S. J.; Wragg, F. P. H.; Nutter, J.; Kalberer, M.

    2014-04-08

      a   wide   range   of   inorganic   and   organic  72   compounds   such   as   transition  metals,   hydrogen  peroxide   (H2O2),   radicals   (e.g.,  73   OH??,  O2???),  and  organic  (hydro...   H2O2  were  used  to  optimize  operation  conditions  of  the  on-­?line  instrument  and  276   to   compare   the   performance   of   on-­?line   and   off-­?line   quantification   methods.  277...

  4. 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-Hřyvik, 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-Alnćs, Grethe Irene; Nebdal, Daniel; Syvänen, Ann-Christine; Rřdningen, Olaug; Alsner, Jan; Overgaard, Jens; Borresen-Dale, Anne-Lise; K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo ; Fossĺ, 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.

  5. Reactive oxygen species mediate Cr(VI)-induced carcinogenesis through PI3K/AKT-dependent activation of GSK-3?/?-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-3?/?-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 ?-catenin almost completely suppressed the Cr(VI)-mediated increase in total and active ?-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-3?, ?-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-3?/?-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-3?/?-catenin signaling involved in Cr(VI) carcinogenesis. • The inhibition of apoptosis and autophagy contributes to Cr(VI) carcinogenesis.

  6. Nicotine stimulates urokinase-type plasminogen activator receptor expression and cell invasiveness through mitogen-activated protein kinase and reactive oxygen species signaling in ECV304 endothelial cells

    SciTech Connect (OSTI)

    Khoi, Pham Ngoc; Park, Jung Sun; Kim, Nam Ho; Jung, Young Do, E-mail: ydjung@chonnam.ac.kr

    2012-03-01

    Urokinase-type plasminogen activator receptor (uPAR) expression is elevated during inflammation, tissue remodeling and in many human cancers. This study investigated the effect of nicotine, a major alkaloid in tobacco, on uPAR expression and cell invasiveness in ECV304 endothelial cells. Nicotine stimulated uPAR expression in a dose-dependent manner and activated extracellular signal-regulated kinases-1/2 (Erk-1/2), c-Jun amino-terminal kinase (JNK) and p38 mitogen activated protein kinase (MAPK). Specific inhibitors of MEK-1 (PD98059) and JNK (SP600125) inhibited the nicotine-induced uPAR expression, while the p38 MAPK inhibitor SB203580 did not. Expression vectors encoding dominant negative MEK-1 (pMCL-K97M) and JNK (TAM67) also prevented nicotine-induced uPAR promoter activity. The intracellular hydrogen peroxide (H{sub 2}O{sub 2}) content was increased by nicotine treatment. The antioxidant N-acetylcysteine prevented nicotine-activated production of reactive oxygen species (ROS) and uPAR expression. Furthermore, exogenous H{sub 2}O{sub 2} increased uPAR mRNA expression. Deleted and site-directed mutagenesis demonstrated the involvement of the binding sites of transcription factor nuclear factor-kappaB (NF-?B) and activator protein (AP)-1 in the nicotine-induced uPAR expression. Studies with expression vectors encoding mutated NF-?B signaling molecules and AP-1 decoy confirmed that NF-?B and AP-1 were essential for the nicotine-stimulated uPAR expression. MAPK (Erk-1/2 and JNK) and ROS functioned as upstream signaling molecules in the activation of AP-1 and NF-?B, respectively. In addition, ECV304 endothelial cells treated with nicotine displayed markedly enhanced invasiveness, which was partially abrogated by uPAR neutralizing antibodies. The data indicate that nicotine induces uPAR expression via the MAPK/AP-1 and ROS/NF-?B signaling pathways and, in turn, stimulates invasiveness in human ECV304 endothelial cells. -- Highlights: ? Endothelial cells treated with nicotine displayed enhanced invasiveness. ? Nicotine induces uPAR expression and, in turn, stimulates invasiveness. ? MAPK/AP-1 and ROS/NF-?B signals are involved in nicotine-induced uPAR.

  7. Rat colonic reactive oxygen species production and DNA damage are mediated by diet and age 

    E-Print Network [OSTI]

    Henderson, Cara Aletha Everett

    2001-01-01

    increase with age, and it is possible that ROS and/or DNA damage accumulate in aged animals and lead to carcinogenic mutations. Dietary factors, particularly fat and fiber, are important risk modifiers of colon cancer. Differences in the production of ROS...

  8. Detection of reactive oxygen species by flow cytometry after spinal cord injury

    E-Print Network [OSTI]

    Shi, Riyi

    introduced a fixation step (with formaldehyde) between the dye loading and dissociation. As a result; Lipid peroxidation; Spinal cord injury; Formaldehyde 1. Introduction Increasing evidence suggests level of ROS or causing ROS production. The purpose of this study is to introduce a new procedure

  9. 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.

  10. On-Line Measurement of Particle-Bound Reactive Oxygen Species (ROS) Francis P. H. Wragg, Stephen J. Fuller, Markus Kalberer

    E-Print Network [OSTI]

    Jackson, Sophie

    equiv. per m3 air 1. Particle collector: Converts aerosol sample from gas phase to liquid phase 2, P. K., Sun, L., Chalupa, D. C. & Ut

  11. 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.

  12. Generation of DNA-Damaging Reactive Oxygen Species via the Autoxidation of Hydrogen Sulfide under Physiologically Relevant

    E-Print Network [OSTI]

    Gates, Kent. S.

    Generation of DNA-Damaging Reactive Oxygen Species via the Autoxidation of Hydrogen Sulfide under found that micromolar concentrations of H2S generated single-strand DNA cleavage. Mechanistic studies indicate that this process involved autoxidation of H2S to generate superoxide, hydrogen peroxide, and

  13. Effects of oxygenate concentration on species mole fractions in premixed n-heptane flames

    E-Print Network [OSTI]

    Senkan, Selim M.

    -heptane/oxygenate mixtures were 2.7 and 3.4. Three different fuel oxygenates (i.e. MTBE, methanol, and ethanol) were tested in these emissions is the improvement in motor vehicle fuel properties. Fuel oxygenates were first used as an octane.e. oxygenates) such as alcohols (e.g. methanol, ethanol, and tertiary butyl alcohol) and ethers (e.g. methyl

  14. Increased reactive oxygen species production during reductive stress: The roles of mitochondrial glutathione and thioredoxin reductases

    E-Print Network [OSTI]

    Korge, P; Calmettes, G; Weiss, JN

    2015-01-01

    hydrogen peroxide production as determined by the pyridinereactive oxygen production, J. Biol. Chem. 280 (2005) 25305–NADPH fuels superoxide production in the failing heart, J.

  15. An Inherited Heteroplasmic Mutation in Mitochondrial Gene COI in a Patient with Prostate Cancer Alters Reactive Oxygen, Reactive Nitrogen and Proliferation

    E-Print Network [OSTI]

    2013-01-01

    reactive nitrogen species (RNS). 2. Materials and MethodsAssay for ROS and RNS. Peroxides Assay: Lymphoblasts werebelow (“Cybrid ROS and RNS”). 3.4. Cybrid Generation. In

  16. Origin of oxygen species in Titan's atmosphere S. M. Horst,1

    E-Print Network [OSTI]

    Yelle, Roger V.

    that the main nitrogen- and carbon- bearing species in the solar nebula were either N2 and CO or NH3 and CH4- rated into Titan as it accreted [Owen, 1982]. This hypothesis also implies that CO was the main carbon-bearing

  17. Evidence of the production of hot hydrogen atoms in RF plasmas by catalytic reactions between hydrogen and oxygen species

    E-Print Network [OSTI]

    Jonathan Phillips; Chun Ku Chen; Randell Mills

    2005-08-31

    Selective H-atom line broadening was found to be present throughout the volume (13.5 cm ID x 38 cm length) of RF generated H2O plasmas in a GEC cell. Notably, at low pressures (ca. hydrogen was 'hot' with energies greater than 40 eV with a pressure dependence, but only a weak power dependence. The degree of broadening was virtually independent of the position studied within the GEC cell, similar to the recent finding for He/H2 and Ar/H2 plasmas in the same GEC cell. In contrast to the atomic hydrogen lines, no broadening was observed in oxygen species lines at low pressures. Also, in control Xe/H2 plasmas run in the same cell at similar pressures and adsorbed power, no significant broadening of atomic hydrogen, Xe, or any other lines was observed. Stark broadening or acceleration of charged species due to high electric fields can not explain the results since (i) the electron density was insufficient by orders of magnitude, (ii) the RF field was essentially confined to the cathode fall region in contrast to the broadening that was independent of position, and (iii) only the atomic hydrogen lines were broadened. Rather, all of the data is consistent with a model that claims specific, predicted, species can act catalytically through a resonant energy transfer mechanism to create hot hydrogen atoms in plasmas.

  18. 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.

  19. 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.

  20. 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.

  1. Antiplatelet effect of phloroglucinol is related to inhibition of cyclooxygenase, reactive oxygen species, ERK/p38 signaling and thromboxane A{sub 2} production

    SciTech Connect (OSTI)

    Chang, Mei-Chi [Biomedical Science Team, Chang Gung University of Science and Technology, Taoyuan, Taiwan (China)] [Biomedical Science Team, Chang Gung University of Science and Technology, Taoyuan, Taiwan (China); Chang, Hsiao-Hua [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China)] [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China); Chan, Chiu-Po [Department of Dentistry, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan (China)] [Department of Dentistry, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan (China); Chou, Han-Yi; Chang, Bei-En [Graduate Institute of Oral Biology, National Taiwan University Medical College, Taipei, Taiwan (China)] [Graduate Institute of Oral Biology, National Taiwan University Medical College, Taipei, Taiwan (China); Yeung, Sin-Yuet [Department of Dentistry, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan (China)] [Department of Dentistry, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan (China); Wang, Tong-Mei [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China)] [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China); Jeng, Jiiang-Huei, E-mail: jhjeng@ntu.edu.tw [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China)] [Laboratory of Pharmacology and Toxicology, School of Dentistry and Department of Dentistry, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan (China)

    2012-09-15

    Platelet dysfunction is a major risk factor of cardiovascular diseases such as atherosclerosis, stroke and myocardial infarction. Many antiplatelet agents are used for prevention and treatment of these diseases. In this study, phloroglucinol (2.5–25 ?M) suppressed AA-induced platelet aggregation and thromboxane B{sub 2} (TXB{sub 2}) production, but not U46619-induced platelet aggregation. Phloroglucinol (100–250 ?M) showed little cytotoxicity to platelets. Phloroglucinol inhibited the COX-1 and COX-2 activities by 45–74% and 49–72% respectively at concentrations of 10–50 ?M. At concentrations of 1 and 5 ?M, phloroglucinol attenuated the AA-induced ROS production in platelets by 30% and 53%, with an IC{sub 50} of 13.8 ?M. Phloroglucinol also inhibited the PMA-stimulated ROS production in PMN. Preincubation of platelets by phloroglucinol (10–25 ?M) markedly attenuated the AA-induced ERK and p38 phosphorylation. Intravenous administration of phloroglucinol (2.5 and 5 ?mol/mouse) suppressed the ex vivo AA-induced platelet aggregation by 57–71%. Phloroglucinol administration also elevated the mice tail bleeding time. Moreover, phloroglucinol inhibited the IL-1?-induced PGE{sub 2} production in pulp fibroblasts. These results indicate that antiplatelet and anti-inflammatory effects of phloroglucinol are related to inhibition of COX, ROS and TXA2 production as well as ERK/p38 phosphorylation in platelets. Phloroglucinol further suppress PMA-induced ROS production in PMN. The antiplatelet effect of phloroglucinol was confirmed by ex vivo study. Clinically, the consumption of phloroglucinol-containing food/natural products as nutritional supplement may be helpful to cardiovascular health. Phloroglucinol has potential pharmacological use. -- Highlights: ? Phloroglucinol suppressed AA-induced platelet aggregation and thromboxane production. ? Phloroglucinol inhibited COX activity and IL-1b-induced PGE2 production in fibroblast. ? Phloroglucinol declined platelet and PMN ROS production and ERK/p38 phosphorylation. ? Phloroglucinol suppressed ex vivo AA-induced platelet aggregation. ? Phloroglucinol may prevent and for treatment of atherosclerosis/ vascular diseases.

  2. CO Desorption from Oxygen Species on Carbonaceous Surface: 1. Effects of the Local Structure of the Active Site and the Surface Coverage

    E-Print Network [OSTI]

    Truong, Thanh N.

    -level understanding on the desorption of carbon monoxide from surface oxygen complexes that are formed of chars and carbons in reactions with oxygenated agents in the combustion and gasification processes has in the gasification and combustion of coal. Particularly, a CO molecule release from carbonyl oxygen complexes

  3. Nox1 and Nox4 enzymes are persistently elevated in human hepatocytes producing infectious hepatitis C virus

    E-Print Network [OSTI]

    Reyes de Mochel, Nabora Soledad

    2009-01-01

    reactive nitrogen species (RNS), superoxide dismutase (SOD),oxygen/nitrogen species (ROS/RNS) has been observed alongan increased generation of ROS/RNS during HCV infection. DNA

  4. Redox regulation of hepatitis C in nonalcoholic and alcoholic liver

    E-Print Network [OSTI]

    Seronello, Scott; Sheikh, Muhammad Y.; Choi, Jinah

    2007-01-01

    ?B, nuclear factor kappa B; RNS, reactive nitrogen species;oxygen/nitrogen species (ROS/RNS) and decreased antioxidantincrease the levels of ROS/RNS, oxidized thioredoxin, lipid

  5. Epithelial–mesenchymal 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 epithelial–mesenchymal 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: Epithelial–mesenchymal 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 transformation.

  6. 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.

  7. Impact of the renewable oxygenate standard for reformulated gasoline on ethanol demand, energy use, and greenhouse gas emissions

    SciTech Connect (OSTI)

    Stork, K.C.; Singh, M.K.

    1995-04-01

    To assure a place for renewable oxygenates in the national reformulated gasoline (RFG) program, the US Environmental Protection Agency has promulgated the renewable oxygenate standard (ROS) for RFG. It is assumed that ethanol derived from corn will be the only broadly available renewable oxygenate during Phase I of the RFG program. This report analyzes the impact that the ROS could have on the supply of ethanol, its transported volume, and its displacement from existing markets. It also considers the energy and crude oil consumption and greenhouse gas (GHG) emissions that could result from the production and use of various RFGs that could meet the ROS requirements. The report concludes that on the basis of current and projected near-term ethanol capacity, if ethanol is the only available renewable oxygenate used to meet the requirements of the ROS, diversion of ethanol from existing use as a fuel is likely to be necessary. Year-round use of ethanol and ETBE would eliminate the need for diversion by reducing winter demand for ethanol. On an RFG-program-wide basis, using ethanol and ETBE to satisfy the ROS can be expected to slightly reduce fossil energy use, increase crude oil use, and have essentially no effect on GHG emissions or total energy use relative to using RFG oxygenated only with MTBE.

  8. Mitochondrial DNA Variants Mediate Energy Production and Expression Levels for CFH, C3 and EFEMP1 Genes: Implications for Age-Related Macular Degeneration

    E-Print Network [OSTI]

    2013-01-01

    Oxygen/Nitrogen Species (ROS/RNS) Assay The H haplogroup andexposed to the reagent and ROS/RNS production measured withfunction (production of ROS/RNS, ATP, and lactate) were

  9. 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 alterations in mitochondrial function. • ??{sub m} decrease in state 3 may be responsible for the decreased ATP production. • Mild uncoupling prevents mitochondrial oxidative damage.

  10. Humic acid in drinking well water induces inflammation through reactive oxygen species generation and activation of nuclear factor-?B/activator protein-1 signaling pathways: A possible role in atherosclerosis

    SciTech Connect (OSTI)

    Hseu, You-Cheng [Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan (China); Department of Molecular and Cellular Oncology, University of Texas, MD Anderson Cancer Center, TX 77030 (United States); Senthil Kumar, K.J. [Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan (China); Chen, Chih-Sheng; Cho, Hsin-Ju; Lin, Shu-Wei; Shen, Pei-Chun [Institute of Nutrition, China Medical University, Taichung 40402, Taiwan (China); Lin, Cheng-Wen [Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 40402, Taiwan (China); Lu, Fung-Jou [Institute of Medicine, Chun Shan Medical University, Taichung 40201, Taiwan (China); Yang, Hsin-Ling, E-mail: hlyang@mail.cmu.edu.tw [Institute of Nutrition, China Medical University, Taichung 40402, Taiwan (China); Department of Molecular and Cellular Oncology, University of Texas, MD Anderson Cancer Center, TX 77030 (United States)

    2014-01-15

    Humic acid (HA) has been implicated as one of the etiological factors in the peripheral vasculopathy of blackfoot disease (BFD) in Taiwan. However, the underlying pathophysiological mechanisms of BFD are not well defined. In this study, we used an in vitro and in vivo model, in which HA (25–200 ?g/mL) activated macrophages to produce pro-inflammatory molecules by activating their transcriptional factors. HA exposure induced NO and PGE{sub 2} production followed by induction of iNOS and COX-2 through NF-?B/AP-1 transactivation in macrophages. In addition, the production of TNF-? and IL-1? was significantly increased by HA. Moreover, HA-induced iNOS and COX-2 expression were down-regulated by the NF-?B and AP-1 inhibitors pyrrolidine dithiocarbamate (PDTC) and Tanshinone, respectively. Furthermore, generations of ROS and nitrotyrosine, as well as activation of the AKT and MAPKs signaling cascades were observed after HA exposure. Specifically, HA-induced NF-?B activation was mediated by ROS and AKT, and that HA-induced AP-1 activation was mediated by JNK and ERK. Notably, HA-mediated AKT, JNK, and ERK activation was ROS-independent. The inflammatory potential of HA was correlated with increased expression of HO-1 and Nrf2. Furthermore, an in vivo study confirms that mice exposed to HA, the serum levels of TNF-? and IL-1? was significantly increased in a dose-dependent manner. This report marks the first confirmation that environmental exposure of HA induces inflammation in macrophages, which may be one of the main causes of early atherogenesis in blackfoot disease. - Highlights: • Humic acid (HA) induce pro-inflammatory cytokines and mediators in macrophages. • HA-induced inflammation is mediated by ROS and NF-?B/AP-1 signaling pathways. • The inflammatory potential of HA correlated with activation of Nrf2/HO-1 genes. • HA exposure to mice increased pro-inflammatory cytokines production in vivo. • HA may be one of the main causes of early atherogenesis in blackfoot disease.

  11. EFFICIENT OXYGEN SEPARATION MEMBRANE

    E-Print Network [OSTI]

    Mucina, Ladislav

    EFFICIENT OXYGEN SEPARATION MEMBRANE Summary of technology Oxygen can be separated from air using a uniquely structured ceramic ion transport membrane for oxygen separation thatshowsremarkablyhighflux © Curtin University 2013 Gas diffusion in conventional membrane Gas diffusion in new membrane New membrane

  12. Oxygen-producing inert anodes for SOM process

    SciTech Connect (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.

  13. 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.

  14. 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.

  15. 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.

  16. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, Fernando H. (Sante Fe, NM); Chung, Brandon W. (Los Alamos, NM); Raistrick, Ian D. (Los Alamos, NM); Brosha, Eric L. (Los Alamos, NM)

    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.

  17. The Oncogenic Lung Cancer Fusion Kinase CD74-ROS Activates a Novel Invasiveness Pathway through E-Syt1 Phosphorylation

    E-Print Network [OSTI]

    Johnson, Hannah

    Patients with lung cancer often present with metastatic disease and therefore have a very poor prognosis. The recent discovery of several novel ROS receptor tyrosine kinase molecular alterations in non–small cell lung ...

  18. Evaluating Impact in the ROS Ecosystem William Curran1, Thomas Thornton2, Benjamin Arvey1, and William D. Smart1

    E-Print Network [OSTI]

    Smart, William

    Evaluating Impact in the ROS Ecosystem William Curran1, Thomas Thornton2, Benjamin Arvey1William Curran, Benjamin Arvey and William D. Smart are with the Robotics Program in the School

  19. Magnetic interaction in oxygenated alpha Fe-phthalocyanines

    SciTech Connect (OSTI)

    Kuzmann, Ern?, E-mail: kuzmann@caesar.elte.hu; Homonnay, Zoltán; Horváth, Attila [Institute of Chemistry, Eötvös Loránd 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); Klencsár, Zoltán [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 Mössbauer spectroscopy, magnetization measurements (SQUID) and X-ray diffractometry (XRD). Mössbauer 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 Mössbauer spectra in a 5 T external magnetic field at 5K and magnetization measurements indicate antiferromagnetic coupling in oxygenated ?-FePc.

  20. Transport and metabolism of symplastic and apoplastic ascorbate during oxidative stress 

    E-Print Network [OSTI]

    Parsons, Harriet T

    2009-01-01

    Reactive oxygen species (ROS) are produced continuously in plants and act as important signalling molecules in many cellular processes including stress and defence responses. ROS can arise from external sources as well ...

  1. Protective effects of lipoic acid on chrysene-induced toxicity on M?ller cells in vitro

    E-Print Network [OSTI]

    Mansoor, Saffar; Gupta, Navin; Luczy-Bachman, Georgia; Limb, G. Astrid; Kuppermann, Baruch D.; Kenney, M. Cristina

    2013-01-01

    oxygen/nitrogen species (ROS/RNS) was measured with a 2’,7’-concentration, elevated ROS/RNS levels, decreased ??m value,75.7%, pRNS levels (80.02%, p<0.001),

  2. Cell death: protein misfolding and neurodegenerative diseases

    E-Print Network [OSTI]

    Nakamura, Tomohiro; Lipton, Stuart A.

    2009-01-01

    of reactive nitrogen species (RNS) and reactive oxygen21 in?ux and generation of RNS/ROS It is well known that theconnec- tion between ROS/RNS and mitochondrial dysfunction

  3. Redox signaling via the molecular chaperone BiP protects cells against endoplasmic reticulum-derived oxidative stress

    E-Print Network [OSTI]

    Wang, Jie

    Oxidative protein folding in the endoplasmic reticulum (ER) has emerged as a potentially significant source of cellular reactive oxygen species (ROS). Recent studies suggest that levels of ROS generated as a byproduct of ...

  4. Solid state oxygen sensor

    DOE Patents [OSTI]

    Garzon, Fernando H. (Santa Fe, NM); Brosha, Eric L. (Los Alamos, NM)

    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.

  5. A N-acetyl cysteine ruthenium tricarbonyl conjugate enables simultaneous release of CO and ablation of ROS species

    E-Print Network [OSTI]

    Seixas, Joăo D.; Chaves-Ferreira, Miguel; Montes-Grajales, Diana; Gonçalves, Ana M.; Marques, Ana R.; Saraiva, Lígia M.; Olivero-Verbel, Jesus; Romăo, Carlos C.; Bernardes, Gonçalo J. L.

    2015-08-03

    ] The off-white powder isolated analyses correctly for the stoichiometry of the [a] Dr. J. D. Seixas, Dr. M. Chaves-Ferreira These authors contributed equally to this work. [b] Dr J. D. Seixas, Dr. M. Chaves-Ferreira, Dr. G. J. L. Bernardes Instituto de... organometallic probe that turns fluorescence on upon a selective reaction with CO through a palladium-mediated carbonylation reaction.[31] Importantly, they also showed that the fluorescence of COP-1 in buffer is turned on either by CO gas or by CORM-3. Again...

  6. 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 I?B-? plasmid or pretreatment with Bay 11-7082, a selective inhibitor of NF-?B, 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-?B 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-induced MMP-12 expression. • p38 MAPK/NF-?B signaling pathway modulates ethanol-induced Nox2 expression.

  7. 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.

  8. Oxygen partial pressure sensor

    DOE Patents [OSTI]

    Dees, Dennis W. (Downers Grove, IL)

    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.

  9. Effects of ethanol and reactive species on Hepatitis C virus

    E-Print Network [OSTI]

    Seronello, Scott E.

    2010-01-01

    the mutation rate of hepatitis C virus RNA. Manuscript inreactive oxygen species during hepatitis C virus infection.2010) Ethanol enhances hepatitis C virus replication through

  10. Single-walled carbon nanotubes as near infrared fluorescent sensors : characterization, biological and analytical applications

    E-Print Network [OSTI]

    Jin, Hong, Ph. D. Massachusetts Institute of Technology

    2010-01-01

    Reactive oxygen species (ROS) have emerged as biological signaling molecules, participating in newly discovered cascades that govern cell proliferation, migration, and pathogenesis. A major challenge in understanding these ...

  11. 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.

  12. 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.

  13. Oxygen ion conducting materials

    DOE Patents [OSTI]

    Vaughey, John (Elmhurst, IL); Krumpelt, Michael (Naperville, IL); Wang, Xiaoping (Downers Grove, IL); Carter, J. David (Bolingbrook, IL)

    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.

  14. 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.

  15. 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.

  16. Atomic Oxygen in the Comae of Comets

    E-Print Network [OSTI]

    Anita L. Cochran

    2008-07-03

    We report on the detection of atomic oxygen lines in the spectra of 8 comets. These forbidden lines are a result of the photodissociation of the parent oxygen-bearing species directly into an excited state. We used high resolution spectra obtained at the McDonald Observatory 2.7m telescope to resolve the cometary oxygen lines from the telluric oxygen lines and from other cometary emissions. We find that the relative intensities of the two red lines (6300.304 and 6363.776A) are consistent with theory. The green line (5577.339A) has an intensity which is about 10% of the sum of the intensities of the two red lines. We show that collisional quenching may be important in the inner coma. If we assume the relative excitation rates of potential parents which have appeared in the literature, then H2O would be the parent of the cometary green oxygen line. However, those rates have been questioned. We measured the width of the three oxygen lines and find that the green line is wider than either of the two red lines. The finding of a wider line could imply a different parent for the green and red lines. However, the constancy of the green to red line flux ratio suggests the parent is the same for these lines but that the exciting photons have different energies.

  17. Randomized Robot Navigation Algorithms Piotr Berman \\Lambda Avrim Blum y Amos Fiat z Howard Karloff x Adi Ros'en --

    E-Print Network [OSTI]

    Fiat, Amos

    Chapter 1 Randomized Robot Navigation Algorithms Piotr Berman \\Lambda Avrim Blum y Amos Fiat z Howard Karloff x Adi Ros'en -- Michael Saks k Abstract We consider the problem faced by a mobile robot rectangular obstacles. We assume the robot has no prior knowledge about the positions or sizes

  18. The novel BH-3 mimetic apogossypolone induces Beclin-1- and ROS-mediated autophagy in human hepatocellular carcinoma cells

    E-Print Network [OSTI]

    Cheng, P.; Ni, Zhenhong; Dai, Xufang; Wang, Bin; Ding, W.; Smith, A Rae; Xu, Liang; Wu, D.; He, Fengtian; Lian, Jiqin

    2013-02-07

    , Pervaiz S. Simultaneous induction of non-canonical autophagy and apoptosis in cancer cells by ROS-dependent ERK and JNK activation. PLoS One 2010; 5: e9996. 34. Yuan Y, Xue X, Guo R-B, Sun X-L, Hu G. Resveratrol enhances the antitumor effects...

  19. 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.

  20. A calcium oxygen secondary battery

    SciTech Connect (OSTI)

    Pujare, N.U.; Semkow, K.W.; Sammells, A.F.

    1988-01-01

    The authors report preliminary work performed in their laboratory on a high-temperature electrochemically reversible calcium-oxygen cell. Following an analogous strategy to that recently discussed for the lithium-oxygen secondary system, this calcium-oxygen cell utilizes stabilized zirconia oxygen vacancy conducting solid electrolytes to achieve effective separation between half-cell reactions.

  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. Optical oxygen concentration monitor

    DOE Patents [OSTI]

    Kebabian, Paul (Acton, MA)

    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.

  3. High pressure oxygen furnace

    DOE Patents [OSTI]

    Morris, Donald E. (Kensington, CA)

    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.

  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. Sensitive Species

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation ofAlbuquerque|Sensitive Species Sensitive Species By avoiding or minimizing the

  6. Focal Fish Species Focal Fish Species Characterization

    E-Print Network [OSTI]

    Focal Fish Species Focal Fish Species Characterization APPENDIX I This chapter describes the fish selected the focal species based on their significance and ability to characterize the health

  7. Retinal Pigment Epithelial (RPE) Verification of melanin function as a light activated ROS scavenger

    E-Print Network [OSTI]

    role in protecting our skin from the damaging effects of UV radiation and in preventing skin cancer officinalis, a species of cuttlefish, were added to cultured human retinal pigment epithelial (RPE) cells only native melanin. These experiments conclusively demonstrate that melanin serves as a light

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

    SciTech Connect (OSTI)

    Kelly, Seán; 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.

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeetingDifferencesPlatinum Fuel Cell Cathode | Stanford

  10. Oxygen Reduction Reaction on Dispersed and Core-Shell Metal Alloy Catalysts: Density Functional Theory Studies 

    E-Print Network [OSTI]

    Hirunsit, Pussana

    2011-10-21

    stability against dissolution, surface Pourbaix diagrams, and reaction mechanisms provide useful predictions on catalyst durability, onset potential for water oxidation, surface atomic distribution, coverage of oxygenated species, and activity. The roles...

  11. Protection by Isoprene against Singlet Oxygen in Leaves Hagit P. Affek and Dan Yakir*

    E-Print Network [OSTI]

    -methyl-1,3-butadiene) protection against effects of singlet oxygen was investigated in Myrtus communis conditions. Isoprene (2-methyl-1,3-butadiene) is emitted by a variety of plant species (Harley et al., 1999

  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

    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 yield and 4 cP in viscosity in comparison to high AA pulp for the oxygen delignification. This difference is also seen for high-kappa SW kraft pulps with an average improvement of {approx}3% in yield and 3 cP in viscosity for low AA high kappa number 50 pulp. Low AA hardwood kappa number 20 pulp had an average improvement of {approx}4% in yield and 6-12 cP in viscosity as compared to high AA pulp. Lower kraft cooking temperature (160 vs. 170 C) in combination with the medium AA provides a practical approach for integrating high kappa pulping of hardwoods (i.e., low rejects) with an advanced extended oxygen delignification stage. ECF pulp bleaching of low and high kappa kraft SW and HW pulps exhibit comparable optical and physical strength properties when bleached D(EPO)D.

  15. Oxygen-reducing catalyst layer

    DOE Patents [OSTI]

    O'Brien, Dennis P. (Maplewood, MN); Schmoeckel, Alison K. (Stillwater, MN); Vernstrom, George D. (Cottage Grove, MN); Atanasoski, Radoslav (Edina, MN); Wood, Thomas E. (Stillwater, MN); Yang, Ruizhi (Halifax, CA); Easton, E. Bradley (Halifax, CA); Dahn, Jeffrey R. (Hubley, CA); O'Neill, David G. (Lake Elmo, MN)

    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.

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. 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.

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

    DOE Patents [OSTI]

    Schwartz, Michael (Boulder, CO); White, James H. (Boulder, CO); Sammels, Anthony F. (Boulder, CO)

    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.

  2. Endangered Species

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES ScienceInformation CompanyEmployeeJonHereEndangered Species

  3. Oxygen detection using evanescent fields

    DOE Patents [OSTI]

    Duan, Yixiang (Los Alamos, NM); Cao, Weenqing (Los Alamos, NM)

    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.

  4. 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.

  5. Polycyclic Aromatic Triptycenes: Oxygen Substitution Cyclization Strategies

    E-Print Network [OSTI]

    VanVeller, Brett

    The cyclization and planarization of polycyclic aromatic hydrocarbons with concomitant oxygen substitution was achieved through acid catalyzed transetherification and oxygen-radical reactions. The triptycene scaffold ...

  6. Engineering MulticomponentNanocatalystsfor Oxygen Reduction ...

    Office of Scientific and Technical Information (OSTI)

    Engineering MulticomponentNanocatalystsfor Oxygen Reduction Citation Details In-Document Search Title: Engineering MulticomponentNanocatalystsfor Oxygen Reduction Authors: Guo,...

  7. 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.

  8. Atmospheric Pressure Humid Argon DBD Plasma for the Application of Sterilization -Measurement and Simulation of Hydrogen, Oxygen, and Hydrogen

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and Simulation of Hydrogen, Oxygen, and Hydrogen Peroxide Formation M.J. Kirkpatrick, B. Dodet, E. Odic Département Energie - Supélec, F-91192 Gif-sur-Yvette cedex, France AbstractHydrogen, oxygen, and hydrogen. The yield of the three species was studied as a function of the discharge power and gas flow rate. Hydrogen

  9. 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.

  10. 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 increased with increasing furnace nitrogen content and furnace temperature, but remained relatively insensitive to variations in fuel injection velocity and firing rate. NOx emissions below 5-10-3 g/MJ (10 ppm-air equivalent at 3% O2 dry) were obtained for furnace temperatures below 1533 K (2300°F) and furnace nitrogen levels between 1 and 40%. CO emissions were typically low (<35 ppm). Detailed in-furnace species measurements revealed the importance of the interior furnace circulation patterns, as influenced by fuel and oxidant injection schemes, on pollutant emissions. The combustion stability traits of several DOC burner arrangements were ascertained through furnace pressure measurements, wit6h increased stability occurring as furnace temperature increased and as the separation distance between fuel and oxidant inputs decreased. Based on current market conditions, oxy-fuel conversion of batch steel reheat furnaces with a DOC burner is justified on the basis of lower utility costs alone. However, conversion of continuous steel reheat furnaces, which are responsible for most steel production, required additional economic incentives, such as further fuel savings, increased furnace productivity, or emission credits.

  11. Dilute oxygen combustion. Phase I report

    SciTech Connect (OSTI)

    NONE

    1997-10-01

    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) (NO{sub x}) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NO{sub x} through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NO{sub x} 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 ({approximately}1366 K) oxidant (7-27% O{sub 2} 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{sup +} 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{sup +} scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW ({approximately}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. NO{sub x} emissions increased with increasing furnace nitrogen content and furnace temperature, but remained relatively insensitive to variations in fuel injection velocity and firing rate. NO{sub x} emissions below 5{times}10{sup -3} g/MJ (10 ppm-air equivalent at 3% O{sub 2} dry) were obtained for furnace temperatures below 1533 K (2300{degree}F) and furnace nitrogen levels between 1 and 40%. CO emissions were typically low (<35 ppm). Detailed in- furnace species measurements revealed the importance of the interior furnace circulation patterns, as influenced by fuel and oxidant injection schemes, on pollutant emissions. The combustion stability traits of several DOC burner arrangements were ascertained through furnace pressure measurements, with increased stability occurring as furnace temperature increased and as the separation distance between fuel and oxidant inputs decreased. Based on current market conditions, oxy-fuel conversion of batch steel reheat furnaces with a DOC burner is justified on the basis of utility costs alone. However, conversion of continuous steel reheat furnaces, which are responsible for most steel production, requires additional economic incentives, such as further fuel savings, increased furnace productivity, or emission credits.

  12. Oxygen uptake of benthic systems 

    E-Print Network [OSTI]

    Priebe, William Franklin

    1972-01-01

    mg/hr/sq m between standard and maximum mixing. Hanes and Irvine (23) made a determination of the effects of temperature on quiescent oxygen uptake rates by covering sludge with aerated water and allowing the supernatant to be totally de- pleted.... ECTROLTSIS STSTDI FOA MEMURIRC BOO. FIGURE 2. SWITCH ELECTROQE IN CONTACT WITH ELECTROIYTE. OXYGEN GENERATOR OFF. FIGURE 3. SWIICH ELECI'RODE NOT IN CONTACT' WITH -' ECTROLYTE. 0 0 0 a 0 0 0 ~ O0 0 o 0 0 o o 0 0 0 0 PIERRE A. HIGH SPEED NIXINC...

  13. TARGET SPECIES Table 1. Terrestrial target species.

    E-Print Network [OSTI]

    that have only one or a very few number of key ecological functions. Functional specialist species could = Critical functional link species, species that are the only ones that perform a specific ecological Merganser Boreal Toad Wolverine FS Horned Grebe Long-toed Salamander CFLS BIRDS House Finch CFLS Northern

  14. Targeting a custom-engineered flavonoid to the mitochondria protects against acute oxidative stress 

    E-Print Network [OSTI]

    Drummond, Nicola Jane

    2015-06-29

    Oxidative stress is caused when there are more reactive oxygen species (ROS), than antioxidants to scavenge them, resulting in damage to cellular components. It has been implicated as a major player at multiple points ...

  15. Neurotoxic mechanisms of methylmercury: cellular and behavior changes 

    E-Print Network [OSTI]

    Bellum, Sairam

    2007-04-25

    episodes was cerebellar ataxia. Recent in vitro studies using cultured granule cells showed that MeHg alters intracellular calcium ion ([Ca2+]i) homeostasis, potentiates reactive oxygen species (ROS) generation and loss of mitochondrial membrane potential...

  16. Comparative Neurotoxicity of Methylmercury and Mercuric Chloride In Vivo and In Vitro 

    E-Print Network [OSTI]

    Thuett, Kerry A.

    2010-10-12

    studies, and Trypan blue exclusion, lactate dehydrogenase activity, and cytotoxicity assays for in vitro studies. Mitochondrial membrane potential (MMP), intracellular calcium ion concentration ([Ca2+]i), and production of reactive oxygen species (ROS...

  17. Methods for separating oxygen from oxygen-containing gases

    DOE Patents [OSTI]

    Mackay, Richard (Lafayette, CO); Schwartz, Michael (Boulder, CO); Sammells, Anthony F. (Boulder, CO)

    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.

  18. 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.

  19. Microchemical systems for singlet oxygen generation

    E-Print Network [OSTI]

    Hill, Tyrone F. (Tyrone Frank), 1980-

    2008-01-01

    Chemical Oxygen-Iodine Lasers (COIL) are a technology of interest for industrial and military audiences. COILs are flowing gas lasers where the gain medium of iodine atoms is collisionally pumped by singlet delta oxygen ...

  20. The Role of Oxygen in Coal Gasification 

    E-Print Network [OSTI]

    Klosek, J.; Smith, A. R.; Solomon, J.

    1986-01-01

    of capital and energy. This paper examines the major factors in oxygen purity selection for typical coal gasifiers. Examples demonstrating the effect of oxygen purity on several processes are presented: production of synthetic natural gas (SNG), integrated...

  1. Microbial oceanography of anoxic oxygen minimum zones

    E-Print Network [OSTI]

    Ulloa, Osvaldo

    Vast expanses of oxygen-deficient and nitrite-rich water define the major oxygen minimum zones (OMZs) of the global ocean. They support diverse microbial communities that influence the nitrogen economy of the oceans, ...

  2. Oxygen addition to sulfur of metal thiolates 

    E-Print Network [OSTI]

    Soma, Takako

    1996-01-01

    chemistry. The oxidation reactions of metal thiolates by hydrogen peroxide, molecular oxygen, dioxiranes, and peracids have been reviewed. The compounds resulting from oxidation and oxygenation of nickel thiolate complexes have been isolated, separated...

  3. 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.

  4. RESEARCH ARTICLE Cichlid species diversity in naturally and anthropogenically turbid

    E-Print Network [OSTI]

    to Nile perch introduction, and decreases in water transparency and dissolved oxygen concentrations due-collapse period, spawning occurred year-round in shallow areas with hard substrates and relatively clear water differentiation in feeding techniques as well as year-round spawning, and both may facilitate species coexistence

  5. FORMATION OF HYDROGEN, OXYGEN, AND HYDROGEN PEROXIDE IN ELECTRON-IRRADIATED CRYSTALLINE WATER ICE

    E-Print Network [OSTI]

    Kaiser, Ralf I.

    also present evidence on the involvement of hydroxyl radicals and possibly oxygen atoms as building the major constituent on the surfaces of small solar system objects such as Kuiper Belt objects (de Bergh to irradiation by energetic species from the solar wind (keV particles), the Galactic cosmic radiation field (ke

  6. Oxygenate Supply/Demand Balances

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry NaturalPrices1Markets16 (next20, 20082008707Oxygenate

  7. Developments in ITM oxygen technology for IGCC

    SciTech Connect (OSTI)

    Stein, V.E.E.; Richards, R.E.

    1999-07-01

    In partnership with the U.S. Department of Energy (DOE), an Air Products-led team (with Ceramatec, Eltron Research, McDermott Technology, NREC, Texaco, the Pennsylvania State University, and the University of Pennsylvania) is developing a new technology for air separation - Ion Transport Membrane Oxygen - based on the use of mixed-conducting ceramic membranes that have both electronic and oxygen ionic conductivity when operated at high temperature, typically 800 to 900 C. Under the influence of an oxygen partial-pressure driving force, the ITM Oxygen process achieves a high-purity, high-flux separation of oxygen from a compressed-air stream. By integrating the energy-rich, oxygen-depleted, non-permeate stream with a gas turbine system, the ITM Oxygen process becomes a co-producer of high-purity oxygen, power, and steam. Under a recent CRADA entitled ``Ion Transport Membranes (ITM) for Oxygen-Blown IGCC Systems and Indirect Coal Liquefaction,'' Air Products and DOE completed an initial quantification of the benefits of an ITM Oxygen-integrated IGCC facility. Compared to the cryogenic oxygen base case, the ITM Oxygen technology can potentially: reduce total installed costs by 7%; improve thermal efficiency for the integrated IGCC system by about 3%, leading to further decreases in carbon dioxide and sulfur emissions; and reduce the cost of generated electric power by more than 6%. The ITM Oxygen development project will proceed in three phases. Phase 1, which commenced under a DOE Cooperative Agreement in October 1998, is a 3-year effort focusing on construction of a technology development unit (TDU) for process concept validation tests at a capacity of 0.1 ton-per-day (TPD) oxygen. To accomplish this objective, the Air Products team will address relevant technical challenges in ITM Oxygen materials, engineering, membrane module development, and performance testing. During Phase 1 the team will also verify the economic prospects for integrating ITM Oxygen technology with IGCC and other advanced power generation systems. After at least one intermediate scaleup, Phase 2 and 3 activities will culminate with scaleup to a 25- to 50-TPD pre-commercial demonstration unit, fully integrated with a gas turbine. Meeting these challenges of developing cost-effective fabrication techniques for ITM Oxygen devices, and successfully integrating them with commercially available gas turbine engines, is key to bringing ITM Oxygen technology to the marketplace.

  8. Device and method for separating oxygen isotopes

    DOE Patents [OSTI]

    Rockwood, Stephen D. (Los Alamos, NM); Sander, Robert K. (Los Alamos, NM)

    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.

  9. book review: Species distribution models for species distribution modellers

    E-Print Network [OSTI]

    Dormann, Carsten F

    2012-01-01

    Mapping  species  distributions:  spa? tial inference and news and update  book review  Species distribution models for species distribution modellers  Ecological niches and 

  10. Sputtering of Oxygen Ice by Low Energy Ions

    E-Print Network [OSTI]

    Muntean, E A; Field, T A; Fitzsimmons, A; Hunniford, C A; McCullough, R W

    2015-01-01

    Naturally occurring ices lie on both interstellar dust grains and on celestial objects, such as those in the outer solar system. These ices are continu- ously subjected to irradiation by ions from the solar wind and/or cosmic rays, which modify their surfaces. As a result, new molecular species may form which can be sputtered off into space or planetary atmospheres. We determined the experimental values of sputtering yields for irradiation of oxygen ice at 10 K by singly (He+, C+, N+, O+ and Ar+) and doubly (C2+, N2+ and O2+) charged ions with 4 keV kinetic energy. In these laboratory experiments, oxygen ice was deposited and irradiated by ions in an ultra high vacuum chamber at low temperature to simulate the environment of space. The number of molecules removed by sputtering was observed by measurement of the ice thickness using laser interferometry. Preliminary mass spectra were taken of sputtered species and of molecules formed in the ice by temperature programmed desorption (TPD). We find that the experi...

  11. 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.

  12. Transient oxygen consumption rate measurements with the BDT?M? oxygen biosensor system

    E-Print Network [OSTI]

    Low, Clarke Alan

    2008-01-01

    Oxygen consumption rate (OCR) is a reliable indicator of tissue health. Recently, the OCR of isolated human islets has been shown to predict transplant outcome in diabetic mice. The Oxygen Biosensor System (OBS) is a ...

  13. Oxygen-Reducing Biocathodes Operating with Passive Oxygen Transfer in Microbial Fuel Cells

    E-Print Network [OSTI]

    Oxygen-Reducing Biocathodes Operating with Passive Oxygen Transfer in Microbial Fuel Cells Xue Xia.R. China Department of Civil and Environmental Engineering, Penn State University, 231Q Sackett Building of the catholyte. To avoid the need for aeration, the ability of biocathodes to function with passive oxygen

  14. 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)

    Günther, T-hat nia Mara Fischer; Kviecinski, Maicon Roberto; Baron, Carla Cristine; Felipe, Karina Bettega; Farias, Mirelle Sifroni; Ourique da Silva, Fabiana; Bücker, Nádia Cristina Falcăo; Pich, Claus Tröger; 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 (2–3-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.

  15. 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.

  16. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL); Kleefisch, Mark S. (Naperville, IL); Kobylinski, Thaddeus P. (Lisle, IL); Morissette, Sherry L. (Las Cruces, NM); Pei, Shiyou (Naperville, IL)

    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.

  17. Oxygen ion-conducting dense ceramic

    DOE Patents [OSTI]

    Balachandran, Uthamalingam (Hinsdale, IL); Kleefisch, Mark S. (Naperville, IL); Kobylinski, Thaddeus P. (Lisle, IL); Morissette, Sherry L. (Las Cruces, NM); Pei, Shiyou (Naperville, IL)

    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.

  18. 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.

  19. 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 concept offers substantial savings over SCR and is an economically attractive alternative to purchasing NOx credits or installing other conventional technologies. In conjunction with the development of oxygen based low NOx technology, Praxair also worked on developing the economically enhancing oxygen transport membrane (OTM) technology which is ideally suited for integration with combustion systems to achieve further significant cost reductions and efficiency improvements. This OTM oxygen production technology is based on ceramic mixed conductor membranes that operate at high temperatures and can be operated in a pressure driven mode to separate oxygen with infinite selectivity and high flux. An OTM material was selected and characterized. OTM elements were successfully fabricated. A single tube OTM reactor was designed and assembled. Testing of dense OTM elements was conducted with promising oxygen flux results of 100% of target flux. However, based on current natural gas prices and stand-alone air separation processes, ceramic membranes do not offer an economic advantage for this application. Under a different DOE-NETL Cooperative Agreement, Praxair is continuing to develop oxygen transport membranes for the Advanced Boiler where the economics appear more attractive.

  20. On the oxygen abundance in our Galaxy

    E-Print Network [OSTI]

    L. S. Pilyugin; F. Ferrini; R. V. Shkvarun

    2003-02-03

    The compilation of published spectra of Galactic HII regions with available diagnostic [OIII]4363 line has been carried out. Our list contains 71 individual measurements of 13 HII regions in the range of galactocentric distances from 6.6 to 14.8 kpc. The oxygen abundances in all the HII regions were recomputed in the same way, using the classic Te - method. The oxygen abundance at the solar galactocentric distance traced by those HII regions is in agreement with the oxygen abundance in the interstellar medium in the solar vicinity derived with high precision from the interstellar absorption lines towards stars. The derived radial oxygen abundance distribution was compared with that for HII regions from the Shaver et al. (1983) sample which is the basis of many models for the chemical evolution of our Galaxy. It was found that the original Shaver et al.'s oxygen abundances are overestimated by 0.2-0.3 dex. Oxygen abundances in HII regions from the Shaver et al. sample have been redetermined with the recently suggested P - method. The radial distribution of oxygen abundances from the Shaver et al. sample redetermined with the P - method is in agreement with our radial distribution of (O/H)_Te abundances.

  1. Modulating tissue mechanics to increase oxygen delivery to tumors

    E-Print Network [OSTI]

    Martin, John Daniel, Ph. D. Massachusetts Institute of Technology

    2015-01-01

    Solid tumors have low oxygen tension - hypoxia - that fuels disease progression and treatment resistance. Thus, strategies for alleviating hypoxia are needed. Two factors affect tissue oxygen levels: oxygen supply via blood ...

  2. Characterization of an oxygen suspension used for intravenous infusion

    E-Print Network [OSTI]

    Peńa, Kristen Helen

    2012-01-01

    Oxygenated fluid mixture can be used to treat critically ill patients suffering from asphyxia, lung injury, and cardiac arrest. This oxygenated fluid delivered intravenously re-oxygenates the bloodstream, allowing for more ...

  3. 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.

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

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

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

  5. 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...

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

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

    Oxygen-Enriched Combustion for Military Diesel Engine Generators Oxygen-Enriched Combustion for Military Diesel Engine Generators Substantial increases in brake power and...

  7. 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 Advantages of Oxygenates Fuels over Gasoline in Direct Injection Spark Ignition Engines...

  8. Preservation of a species

    E-Print Network [OSTI]

    Witt, Sarah (Sarah Elizabeth)

    2011-01-01

    To put it simply, humans are going extinct. I identify the source of the problem as an imperceptible societal trend to eliminate the experience that authenticates us as a living species: failure. We've unanimously designated ...

  9. Design optimization of oxygenated fluid pump

    E-Print Network [OSTI]

    Piazzarolo, Bruno Aiala

    2012-01-01

    In medical emergencies, an oxygen-starved brain quickly suffers irreparable damage. In many cases, patients who stop breathing can be resuscitated but suffer from brain damage. Dr. John Kheir from Boston Children's Hospital ...

  10. Dynamic Nuclear Polarization of Oxygen-17

    E-Print Network [OSTI]

    Michaelis, Vladimir K.

    Oxygen-17-detected DNP NMR of a water/glycerol glass enabled an 80-fold enhancement of signal intensity at 82 K, using the biradical TOTAPOL. The >6000-fold savings in acquisition time enable [superscript 17]O–[superscript ...

  11. OXYGEN DIFFUSION IN HYPOSTOICHIOMETRIC URANIUM DIOXIDE

    E-Print Network [OSTI]

    Kim, Kee Chul

    2010-01-01

    IN HYPOSTOICHIOMETRIC URANIUM DIOXIDE Kee Chul Kim Ph.D.727-366; Figure 1. Oxygen-uranium phase-equilibrium _ystem [18]. uranium dioxide powders and 18 0 enriched carbon

  12. Oxygen Enriched Combustion System Performance Study 

    E-Print Network [OSTI]

    Chen, S. L.; Kwan, Y.; Abele, A. R.; Silver, L. S.; Kobayashi, H.

    1987-01-01

    i ndustri al furnaces, such as gl ass melting furnaces, appear to be the most promising appli cations for oxygen enriched combustion. In these applications, the principal energy savings results from minimizing the fuel energy required to heat... with non-water cooled refractory burner til es. The Oxytherm Burner was developed jointly by Maxon and Corning Glass for application of oxygen/fuel combustion in glass furnaces. This burner is also a non-water cooled refractory design with a specially...

  13. Underground coal gasification using oxygen and steam

    SciTech Connect (OSTI)

    Yang, L.H.; Zhang, X.; Liu, S. [China University of Mining & Technology, Xuzhou (China)

    2009-07-01

    In this paper, through model experiment of the underground coal gasification, the effects of pure oxygen gasification, oxygen-steam gasification, and moving-point gasification methods on the underground gasification process and gas quality were studied. Experiments showed that H{sub 2} and CO volume fraction in product gas during the pure oxygen gasification was 23.63-30.24% and 35.22-46.32%, respectively, with the gas heating value exceeding 11.00 MJ/m{sup 3}; under the oxygen-steam gasification, when the steam/oxygen ratio stood at 2: 1, gas compositions remained virtually stable and CO + H{sub 2} was basically between 61.66 and 71.29%. Moving-point gasification could effectively improve the changes in the cavity in the coal seams or the effects of roof inbreak on gas quality; the ratio of gas flowing quantity to oxygen supplying quantity was between 3.1:1 and 3.5:1 and took on the linear changes; on the basis of the test data, the reasons for gas quality changes under different gasification conditions were analyzed.

  14. Magnetism in Lithium–Oxygen 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 lithium–oxygen 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 lithium–oxygen batteries. We demonstrate that the major discharge product formed in the lithium–oxygen 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.

  15. Oxygen Chemistry in the Circumstellar Envelope of the Carbon-Rich Star IRC+10216

    E-Print Network [OSTI]

    Marcelino Agundez; Jose Cernicharo

    2006-05-25

    In this paper we study the oxygen chemistry in the C-rich circumstellar shells of IRC+10216. The recent discoveries of oxygen bearing species (water, hydroxyl radical and formaldehyde) toward this source challenge our current understanding of the chemistry in C-rich circumstellar envelopes. The presence of icy comets surrounding the star or catalysis on iron grain surfaces have been invoked to explain the presence of such unexpected species. This detailed study aims at evaluating the chances of producing O-bearing species in the C-rich circumstellar envelope only by gas phase chemical reactions. For the inner hot envelope, it is shown that although most of the oxygen is locked in CO near the photosphere (as expected for a C/O ratio greater than 1), some stellar radii far away species such as H2O and CO2 have large abundances under the assumption of thermochemical equilibrium. It is also shown how non-LTE chemistry makes very difficult the CO-->H2O,CO2 transformation predicted in LTE. Concerning the chemistry in the outer and colder envelope, we show that formaldehyde can be formed through gas phase reactions. However, in order to form water vapor it is necessary to include a radiative association between atomic oxygen and molecular hydrogen with a quite high rate constant. The chemical models explain the presence of HCO+ and predict the existence of SO and H2CS (which has been detected in a 3 mm line survey to be published). We have modeled the line profiles of H2CO, H2O, HCO+, SO and H2CS using a non-local radiative transfer model and the abundance profiles predicted by our chemical model. The results have been compared to the observations and discussed.

  16. 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 using a Membrane-PSA system.

  17. High energy density lithium-oxygen secondary battery

    SciTech Connect (OSTI)

    Sammells, A.F.

    1989-02-07

    A high energy density lithium-oxygen secondary cell is described comprising a lithium-containing negative electrode; a lithium ion conducting molten salt electrolyte contacting the negative electrode; an oxygen ion conducting solid electrolyte contacting and containing the molten salt electrolyte; and an oxygen redox positive electrode contacting the oxygen ion conducting solid electrolyte.

  18. 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.

  19. Oxygen abundance of open cluster dwarfs

    E-Print Network [OSTI]

    Z. -X. Shen; X. -W. Liu; H. -W. Zhang; B. Jones; D. N. C. Lin

    2007-03-30

    We present oxygen abundances of dwarfs in the young open cluster IC 4665 deduced from the OI $\\lambda$7774 triplet lines and of dwarfs in the open cluster Pleiades derived from the [OI] $\\lambda$6300 forbidden line. Stellar parameters and oxygen abundances were derived using the spectroscopic synthesis tool SME (Spectroscopy Made Easy). We find a dramatic increase in the upper boundary of the OI triplet abundances with decreasing temperature in the dwarfs of IC 4665, consistent with the trend found by Schuler et al. in the open clusters Pleiades and M 34, and to a less extent in the cool dwarfs of Hyades (Schuler et al. 2006a) and UMa (King & Schuler 2005). By contrast, oxygen abundances derived from the [OI] $\\lambda$6300 forbidden line for stars in Pleiades and Hyades (Schuler et al. 2006b) are constant within the errors. Possible mechanisms that may lead a varying oxygen triplet line abundance are examined, including systematic errors in the stellar parameter determinations, the NLTE effects, surface activities and granulation. The age-related effects stellar surface activities (especially the chromospheric activities) are suggested by our analysis to blame for the large spreads of oxygen triplet line abundances.

  20. Oxygen isotopes in crystalline silicates of comet Wild 2: A comparison of oxygen isotope systematics between Wild 2 particles

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Oxygen isotopes in crystalline silicates of comet Wild 2: A comparison of oxygen isotope 2012 Keywords: oxygen isotope ratios crystalline silicate comet 81P/Wild 2 solar system formation Stardust Abstract: Oxygen three-isotope ratios of nine crystalline silicate particles from comet Wild 2

  1. Endangered Species Consultation Handbook

    E-Print Network [OSTI]

    Endangered Species Consultation Handbook Procedures for Conducting" " Consz~ltationand Conference Service March 1998 Final #12;FOREWORD It gives us great pleasure to introduce the final Section 7 Handbook Service employees. The Handbook provides internal guidance and establishes national policy for conducting

  2. Heterozygous Mutation of Opa1 in Drosophila Shortens Lifespan Mediated through Increased Reactive Oxygen Species Production

    E-Print Network [OSTI]

    Tang, Sha; Le, Phung Khanh; Tse, Stephanie; Wallace, Douglas C.; Huang, Taosheng

    2009-01-01

    and mitochondrial bioenergetics during aging in Drosophila.mitochondrial bioenergetics. (A) dOpa1 +/2 Drosophila

  3. Generation of reactive oxygen species by a persulfide (BnSSH) Tonika Chatterji,

    E-Print Network [OSTI]

    Gates, Kent. S.

    , prepared from thioacetic anhydride and sulfu- ryl chloride, was reacted with benzyl mercaptan to af- ford acetyl benzyl disulfide (1, Scheme 1).10 Treatment of this compound with 6 N HCl results in removal-strand breaks (Fig. 1). In contrast, benzyl mercaptan (BnSH) induces little or no strand cleavage under

  4. Photochemical Transformation of Carboxylated Multiwalled Carbon Nanotubes: Role of Reactive Oxygen Species

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    to a semiconductor photo- catalyst under UV light, generating electron-hole pairs which leads to graphene oxide lead to changes in their physicochemical properties that govern their mobility and toxicity. Several.3,4 The degradation was attributed to the high oxidative potential of peroxidases and their byproducts

  5. Association of Reactive Oxygen Species Levels and Radioresistance in Cancer Stem Cells

    E-Print Network [OSTI]

    Quake, Stephen R.

    Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA 2.L., T.K., M.J.D., A.K., D.Q., J.S.L., L.A., and M.W. performed the experiments. B.J., M.J.K, I.W., F.W., G.S., C.G., B.P., J.S., and S.K.L. aided in human tumor tissue acquisition. G.S. designed a pre

  6. Direct and indirect photoreactions of chromophoric dissolved organic matter : roles of reactive oxygen species and iron

    E-Print Network [OSTI]

    Goldstone, Jared Verrill, 1971-

    2002-01-01

    Photochemical transformations of chromophoric dissolved organic matter (CDOM) are one of the principal processes controlling its fate in coastal waters. The photochemical decomposition of CDOM leads to the formation of a ...

  7. Green fluorescent protein based indicators of dynamic redox changes and reactive oxygen species

    E-Print Network [OSTI]

    Dooley, Colette

    2006-01-01

    CA), The codon sequence VGB was used to in the forward andnucleotide codon sequence (VGB which encodes for G,C,A at147 was varied by using VGB codon sequence. Proline at

  8. Green fluorescent protein based indicators of dynamic redox changes and reactive oxygen species

    E-Print Network [OSTI]

    Dooley, Colette

    2006-01-01

    tetrachlorodibenzo-p-dioxin or indolo(3,2-b)carbazole isTetrachlorodibenzo-p-dioxin induced cytochrome P450s alterTetrachlorodibenzo-p-dioxin (TCDD, 4 and 100 nM), for 24

  9. Reactive oxygen species play a causal role in multiple forms of insulin resistance

    E-Print Network [OSTI]

    Houstis, Nicholas E

    2007-01-01

    Insulin resistance is a cardinal feature of type 2 diabetes and is characteristic of a wide range of other clinical and experimental settings. Little is known about why insulin resistance occurs in so many contexts. Do the ...

  10. 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 potential for blending into finished fuels. Fractions from the lowest oxygen content oil exhibited some phenolic acidity, but generally contained very low levels of oxygen functional groups. These materials would likely be suitable as refinery feedstocks and potentially as fuel blend components. PIONA analysis of the Light and Naphtha fractions shows benzene content of 0.5 and 0.4 vol%, and predicted (RON + MON)/2 of 63 and 70, respectively.

  11. 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}?) + O{sub 3}(?) ? 2O{sub 2} + O on the removal rate of O{sub 2}(a {sup 1}?) 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}?) 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}?) in the discharge region of the generator. (lasers)

  12. An Advanced Oxygen Trim Control System 

    E-Print Network [OSTI]

    Miller, J. G.

    1985-01-01

    problems that can cause errors. First, the output of the cell is determined by the Nernst equation (B). (B) E RT 4r logn Pl P2 where E e.m.f. (potential) R Gas Co nstant T Absolute Temperature F Faraday Constant P2 Oxygen Partial Pressure...

  13. 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 Bloom baffle burner at GTI. The results are positive and confirm that oxygen-enriched combustion can be carried out without producing higher levels of NOx than normal air firing, if lancing of combustion air is used and the excess air levels are controlled. A simple economic study shows that the membrane processes can produce O{sub 2} at less than $40/ton EPO{sub 2} and an energy cost of 1.1-1.5 MMBtu/ton EPO{sub 2}, which are very favorable compared with conventional technologies such as cryogenics and vacuum pressure swing adsorption processes. The benefits of integrated membrane processes/combustion process trains have been evaluated, and show good savings in process costs and energy consumption, as well as reduced CO{sub 2} emissions. For example, if air containing 30% oxygen is used in natural gas furnaces, the net natural gas savings are an estimated 18% at a burner temperature of 2,500 F, and 32% at a burner temperature of 3,000 F. With a 20% market penetration of membrane-based oxygen-enriched combustion in all combustion processes by 2020, the energy savings would be 414-736 TBtu/y in the U.S. The comparable net cost savings are estimated at $1.2-2.1 billion per year by 2020, calculated as the value of fuel savings subtracted from the cost of oxygen production. The fuel savings of 18%-32% by the membrane/oxygen-enriched combustion corresponds to an 18%-32% reduction in CO{sub 2} emissions, or 23-40 MM ton/y less CO{sub 2} from natural gas-fired furnaces by 2020. In summary, results from this project (Concept Definition phase) are highly promising and clearly demonstrate that membrane processes can produce oxygen-enriched air in a low cost manner that will lower operating costs and energy consumption in industrial combustion processes. Future work will focus on proof-of-concept bench-scale demonstration in the laboratory.

  14. The structure of formate species on Pd(111) calculated by density functional theory and determined using

    E-Print Network [OSTI]

    Saldin, Dilano

    spectroscopy (RAIRS). The oxygen atoms of the formate species were found to be adsorbed over surface palladium 2004 Elsevier B.V. All rights reserved. Keywords: Palladium; Formic acid; Infrared spectroscopy; Low and hydrogen invokes the formation of a stable carboxylate that hydroge- nates to yield alcohols over supported

  15. Part 2. Species Selection Adaptability of Some Eucalyptus Species

    E-Print Network [OSTI]

    Part 2. Species Selection Adaptability of Some Eucalyptus Species in Southwest Oregon1 Lee O. Hunt2-industrial forest 1 Presented at the Workshop on Eucalyptus in California, June 14-16, 1983, Sacramento of harvesting in their life- times. The screening of trials of Eucalyptus species were a part of a personal

  16. Design, measurement, and analysis of oxygenated fluid pump system

    E-Print Network [OSTI]

    Mason, Alexander M., IV (Alexander Martin)

    2012-01-01

    The author sought out the opportunity to design and implement a system for pumping oxygenated fluid and mixing it with saline, for the purpose of providing sufficient levels of oxygen for patients undergoing forms of ...

  17. Oxygen levels in thermoplastic microfluidic devices during cell culture

    E-Print Network [OSTI]

    Ochs, Christopher J.

    We developed a computational model to predict oxygen levels in microfluidic plastic devices during cell culture. This model is based on experimental evaluation of oxygen levels. Conditions are determined that provide ...

  18. On the reduction of oxygen from dispersed media

    E-Print Network [OSTI]

    Roushdy, Omar H., 1977-

    2007-01-01

    The reduction of oxygen from an organic phase dispersed in a concentrated electrolyte is investigated. Dispersed organic phases are used to enhance oxygen transport in fermenters and artificial blood substitutes. This work ...

  19. Phase-based regional oxygen metabolism (PROM) using MRI

    E-Print Network [OSTI]

    Fan, Audrey Peiwen

    Venous oxygen saturation (Yv) in cerebral veins and the cerebral metabolic rate of oxygen (CMRO2) are important indicators for brain function and disease. Although MRI has been used for global measurements of these parameters, ...

  20. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, Roland R. (Lansdale, PA); Bond, James A. (Exton, PA)

    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.

  1. 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.

  2. Which oxygenates is right for you?

    SciTech Connect (OSTI)

    Chang, E.J. [SRI International, Menlo Park, CA (United States)

    1994-12-31

    Recent announcements of additional sources of oxygenates have generated considerable interest. Increasing demand for methyl tert-butyl ether (MTBE) worldwide, especially in the United States for oxygenated fuel and reformulated gasoline (RFG), provides the primary incentive for technologies that produce additional raw material (namely isobutene) and/or alternative oxygenate compounds. Normal butene isomerization and diisopropyl ether (DIPE) are two new processes introduced in 1992 to meet the oxygenate demand. The U.S. Clean Air Act Amendments of 1990 (CAAA) have created a huge demand for capital. Between 1991 and 2000, the U.S. refining industry will need to make capital expenditures of about $37 billion (1990 dollars) to meet refinery regulatory requirements, and to manufacture reformulated gasoline and ultra-low sulfur diesel fuel. To obtain financing, whether internally or from external sources, projects must provide sound economics and pose minimal technological risks. These concerns have prevented several large MTBE projects, involving both established and new technologies, from going forward. The introduction of normal butene isomerization and DIPE processes has generated a great deal of enthusiasm, but neither process had been licensed by the third quarter of 1993. Technology risk is a major barrier to obtaining financing inasmuch as lenders arc unlikely to finance the first commercial application of any technology. Currently, Texas Olefins/Phillips Petroleum and Lyondell have demonstrated normal butene isomerization on a commercial scale in their plants. However, Mobil has not demonstrated the DIPE process beyond the pilot plant stage. In this paper, we assess the technological aspects of normal butene isomerization and DIPE processes, and compare their economics with existing etherification processes.

  3. VARIATIONS IN THE DISSOLVED OXYGEN CONTENT OF INTRAGRAVEL WATER IN

    E-Print Network [OSTI]

    ^402: VARIATIONS IN THE DISSOLVED OXYGEN CONTENT OF INTRAGRAVEL WATER IN FOUR SPAWNING STREAMS IN THE DISSOLVED OXYGEN CONTENT OF INTRAGRAVEL WATER IN FOUR SPAWNING STREAMS OF SOUTHEASTERN ALASKA by William J Introduction 1 Sampling intragravel water for dissolved oxygen content 2 Obtaining water samples from

  4. The oxygen abundance distribution in M101

    E-Print Network [OSTI]

    L. S. Pilyugin

    2001-05-07

    The well-observed spiral galaxy M101 was considered. The radial distributions of oxygen abundances determined in three different ways (with the classic Te - method, with the R23 - method, and with the P -- method) were compared. It was found that the parameters (the central oxygen abundance and the gradient) of the radial O/H(P) abundance distribution are close to those of the O/H(Te) abundance distribution. The parameters of the O/H(R23) abundance distribution differ significantly from those of the O/H(Te) abundance distribution: the central O/H(R23) oxygen abundance is higher by around 0.4dex and the gradient is steeper by a factor of around 1.5 as compared to those values in the O/H(Te) abundance distribution. The dispersion in O/H(P) abundance at fixed radius is rather small, around 0.08 dex, and is equal to that in O/H(Te) abundance. The dispersion in O/H(R23) abundance at fixed radius is appreciably larger, around 0.16 dex, compared to that in O/H(Te) abundance. It has been shown that the extra dispersion in O/H(R23) abundances is an artifact and reflects scatter in excitation parameter P at fixed radius.

  5. 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.

  6. Are hybrid species more fit than ancestral parent species in the current hybrid species habitats?

    E-Print Network [OSTI]

    Rieseberg, Loren

    Are hybrid species more fit than ancestral parent species in the current hybrid species habitats? L Columbia, Vancouver, BC, Canada Introduction Hybridization is receiving renewed attention as an important). For homoploid hybridization in plants, where chromosome number remains the same, models and empirical evi- dence

  7. Thermodynamic stability of oxygen point defects in cubic Zirconia

    E-Print Network [OSTI]

    Samanta, Amit; Li, Ju

    2010-01-01

    Zirconia (ZrO2) is an important material with technological applications which are affected by point defect physics. Ab-initio calculations are performed to understand the structural and electronic properties of oxygen vacancies and interstitials in different charge states in cubic zirconia. We find oxygen interstitials in cubic ZrO2 can have five different configurations - dumbbell, dumbbell, crowd-ion, octahedral, and distorted dumbbell. For a neutral and singly charged oxygen interstitial, the lowest energy configuration is the dumbbell, while for a doubly charged oxygen interstitial the octahedral site is energetically the most favorable. Both the oxygen interstitial and the oxygen vacancy are negative-U, so that the singly charged defects are unstable at any Fermi level. The thermodynamic stability of these defects are studied in terms of Fermi level, oxygen partial pressure and temperature. A method to determine the chemical potential of the system as a function of temperature and pressure is propo...

  8. 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

  9. 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 [Univ. of Wisconsin, Milwaukee, WI (United States). Collece of Engineering and Applied Science; Zhang, Xuran [Wuhan Univ. of Technology, Wuhan (China). School of Science; Qu, Deyu [Wuhan Univ. of Technology, Wuhan (China). School of Science; Yang, Xiao-Qing [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.; Lee, Hung-Sui [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.; Qu, Deyang [Univ. of Wisconsin, Milwaukee, WI (United States). Collece of Engineering and Applied Science

    2015-08-01

    Oxygen reduction and oxygen evolution reactions were studied 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.

  10. Pd-Mediated Activation of Molecular Oxygen in a Nonpolar Jason M. Keith, Robert J. Nielsen, Jonas Oxgaard, and William A. Goddard III*

    E-Print Network [OSTI]

    Goddard III, William A.

    in a toluene-solvated palladium-hydride bond (avoiding palladium zero) has been elucidated using quantum of the hydrogen atom by triplet oxygen, (2) the formation of a stable L2XPdI OOH triplet species, (3) a spin-withdrawing ligands that can stabilize PdI , the reaction will not proceed via the palladium hydride insertion

  11. 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.

  12. Oxygen stabilized zirconium-vanadium-iron alloy

    DOE Patents [OSTI]

    Mendelsohn, Marshall H. (Woodridge, IL); Gruen, Dieter M. (Downers Grove, IL)

    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.

  13. Jupiter Oxygen Corporation | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy ResourcesOrder atHills,New York: EnergyUnlimitedEnergyJuniata,JupiterOxygen

  14. 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 oxygen standards and practices for minimum safety requirements. A summary of operational hazards, along with oxygen safety and emergency procedures, are provided.

  15. 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.

  16. Analytical and characterization studies of organic and inorganic species in brown coal

    SciTech Connect (OSTI)

    G. Domazetis; M. Raoarun; B.D. James; J. Liesegang; P.; J. Pigram; N. Brack [La Trobe University, Vic. (Australia). Department of Chemistry

    2006-08-15

    Detailed studies have been carried out on the distribution of organic functional groups and inorganic species in as-received (ar) and acid-washed (aw) brown coals using elemental analysis, energy dispersive X-ray analysis (SEM-EDX), X-ray photoelectron spectroscopy (XPS), and Time-of-flight-secondary ion mass spectrometry (TOF-SIMS). Surface concentrations of the various carbon groups, organic oxygen, and inorganic hydroxide were obtained using XPS, but oxygen from clay and quartz, if present, interfered with organic oxygen determinations for the coals. A comparison of ar and aw coals using XPS and SEM-EDX is provided in terms of inorganic and organic sulfur groups. Chloride in these coals is present mainly as acid extractable forms, but small amounts of chloride in the organic matrix were indicated by the elemental analysis of ultra low-ash coals. TOF-SIMS fragments from brown coals were indicative of polymers consisting mainly of single aromatic groups linked by hydrocarbons with carboxyl and phenol functional groups. Sulfur fragments were from inorganic sulfur, thiols, organo-sulfates, and S-N-organic species. Numerous fragments containing organically bound chloride were observed. Fragments of the inorganic species Na, Mg, Al, Si, K, Ca, Ti, Cr, Fe, Mn, Ni, Cu, and Ga were also observed. Environmentally undesirable species, particularly from organo-sulfur and organo-chloride groups in brown coal, are likely to emerge from processes that heat coal-water mixture. 54 refs., 3 figs., 10 tabs.

  17. Trait variation within a species determines warming responses at different scales

    SciTech Connect (OSTI)

    Karve, Abhijit A [ORNL; Weston, David [ORNL; Souza, Lara [University of Tennessee, Knoxville (UTK); Classen, Aimee T [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Plant species, and the traits associated with them, can help buffer ecosystems to environmental perturbations. Few studies have examined whether within species variation, both among and within populations, can similarly buffer ecosystems to environmental perturbations, such as climatic warming, across levels of organization. Using a dominant plant species in the eastern US, Solidago altissima, we examined whether genotypes of the same species from both southern and northern latitude populations exhibited differential short-term responses to temperature at the cell, leaf, and plant level. At the cell level we quantified the production of reactive oxygen species (by-product of temperature stress) and total oxygen radical antioxidant capacity (which ameliorates temperature stress by-products). At the leaf and plant levels, we measured CO2 assimilation. Increasing temperatures had strong negative impacts on plant-level carbon gain, but weak impacts on cell-level antioxidant capacity. Southern latitude genotypes had greater total antioxidant capacity, but lower leaf-level carbon gain, than did northern genotypes under elevated temperature. At the plant level, northern and southern genotypes exhibited similar declines in carbon gain under elevated temperature, likely because total plant leaf area was higher for southern genotypes than northern genotypes, which compensated for their lower per unit area leaf-level carbon gain. Overall, short-term temperature-induced declines in carbon gain at the plant level may scale to reduce within species variation, both across and within populations, potentially altering ecosystem carbon cycling.

  18. 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 Lepalovsky; and Translator Vladimir Litvinov. During this trip project participants were to discuss with the project Technical Monitor J.D. Carter and representative of Praxair Inc. J. Chen the results of project activities (prospects of transition metal-doped material application in oxygen pumps), as well as the prospects of cooperation with Praxair at the meeting with the company management in the following fields: (1) Deposition of thin films of oxide materials of complex composition on support by magnetron and ion sputtering, research of coatings properties; (2) Development of block-type structure technology (made of porous and dense ceramics) for oxygen pump. The block-type structure is promising because when the size of electrolyte block is 2 x 2 inches and assembly height is 10 inches (5 blocks connected together) the area of active surface is ca. 290 square inches (in case of 8 slots), that roughly corresponds to one tube with diameter 1 inch and height 100 inches. So performance of the system made of such blocks may be by a factor of two or three higher than that of tube-based system. However one month before the visit, J. Chen notified us of internal changes at Praxair and the cancellation of the visit to Tonawanda, NY. During consultations with the project Technical Monitor J.D. Carter and Senior Project Manager A. Taylor a decision was made to extend the project term by 2 quarters to prepare proposals for follow-on activities during this extension (development of block-type structures made of dense and porous oxide ceramics for electrochemical oxygen pumps) using the funds that were not used for the trip to the US.

  19. Formation of Hydrogen, Oxygen, and Hydrogen Peroxide in Electron Irradiated Crystalline Water Ice

    E-Print Network [OSTI]

    Weijun Zheng; David Jewitt; Ralf I. Kaiser

    2005-11-18

    Water ice is abundant both astrophysically, for example in molecular clouds, and in planetary systems. The Kuiper belt objects, many satellites of the outer solar system, the nuclei of comets and some planetary rings are all known to be water-rich. Processing of water ice by energetic particles and ultraviolet photons plays an important role in astrochemistry. To explore the detailed nature of this processing, we have conducted a systematic laboratory study of the irradiation of crystalline water ice in an ultrahigh vacuum setup by energetic electrons holding a linear energy transfer of 4.3 +/- 0.1 keV mm-1. The irradiated samples were monitored during the experiment both on line and in situ via mass spectrometry (gas phase) and Fourier transform infrared spectroscopy (solid state). We observed the production of hydrogen and oxygen, both molecular and atomic, and of hydrogen peroxide. The likely reaction mechanisms responsible for these species are discussed. Additional formation routes were derived from the sublimation profiles of molecular hydrogen (90-140 K), molecular oxygen (147 -151 K) and hydrogen peroxide (170 K). We also present evidence on the involvement of hydroxyl radicals and possibly oxygen atoms as building blocks to yield hydrogen peroxide at low temperatures (12 K) and via a diffusion-controlled mechanism in the warming up phase of the irradiated sample.

  20. 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.

  1. Heat release analysis of oxygen-enriched diesel combustion

    SciTech Connect (OSTI)

    Assanis, D.; Karvounis, E. (Univ. of Illinois, Urbana, IL (United States)); Sekar, R.; Marr, W. (Argonne National Lab., IL (United States))

    1993-10-01

    A heat release correlation for oxygen-enriched diesel combustion is being developed through heat release analysis of cylinder pressure data from a single-cylinder diesel engine operating under various levels of oxygen enrichment. Results show that standard combustion correlations available in the literature do not accurately describe oxygen-enriched diesel combustion. A novel functional form is therefore proposed, which is shown to reproduce measured heat release profiles closely, under different operating conditions and levels of oxygen enrichment. The mathematical complexity of the associated curve-fitting problem is maintained at the same level of difficulty as for standard correlations. When the novel correlation is incorporated into a computer simulation of diesel engine operation with oxygen enrichment, the latter predicts pressure traces in excellent agreement with measured pressure data. This demonstrates the potential of the proposed combustion simulation to guide the application of oxygen-enriched technology successfully to a variety of multicylinder diesel systems.

  2. 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.

  3. Electrochemical natural gas conversion to more valuable species

    SciTech Connect (OSTI)

    Kuchynka, D.J.; Cook, R.L.; Fammells, A.F. (Eltron Research, Inc., Aurora, IL (US))

    1991-05-01

    This paper reports on the electrochemical oxidative dimerization of methane to give C{sub 2} hydrocarbon species investigated in solid oxide fuel cells possessing the general configuration: CH{sub 4}, anode electrocatalyst/ZrO{sub 2}(8 m/o Y{sub 2}O{sub 3})/La{sub 0.9}Sr{sub 0.1}MnO{sub 3}O{sub 2}(air). Perovskite anode electrocatalysts shown to possess activity toward promoting the subject reaction include Sm{sub 0.5}Ce{sub 0.5}CuO{sub 3}, Tb{sub 0.8}Sm{sub 0.2}CuO{sub 3}, Gd{sub 0.9}Th{sub 0.1}CuO{sub 3}, Gd{sub 0.9}Na{sub 0.1}MnO{sub 3}, and Th{sub 0.8}Yb{sub 0.2}NiO{sub 3}. Maximum partial faradaic current densities at active perovskite anode electrocatalysts for promoting the subject reaction were found to be directly correlatable to their calculated oxygen binding energies on the perovskite surface, where increasing binding energies were found to favor higher rates for electrochemical partial methane oxidation. Increasing surface oxygen binding energies at perovskite anode electrocatalysts were found to correlate with increasing perovskite lattice-free volumes with electrochemical measurements, supporting increasing surface oxygen binding energies and perovskite lattice-free volumes as leading to enhanced rates for the subject reaction. As a consequence, synergism was found between experimentally determined perovskite anode electrocatalyst activities, their calculated surface oxygen binding energies, and lattice ionic-free volumes.

  4. A fiber optic probe for oxygen partial pressure sensing 

    E-Print Network [OSTI]

    Schlain, Leslie Ariel

    1986-01-01

    of the electronic circuitry, and Steve Spar for software development. TABLE OF CONTENTS INTRODUCTION Purpose Current Status of Conventional Oxygen Sensors Optical Sensors Technical Obj ect ives 1 5 10 MATERIAL AND METHODS 14 Transducer Design... the partial pressure of oxygen (p02) in solutions. The research effort was specifically aimed at the development of an oxygen sensor suitable for physiological applications. The sensor described in this thesis is an application of a generic fiber optic...

  5. Strongly enhanced oxygen ion transport through samarium-doped...

    Office of Scientific and Technical Information (OSTI)

    Strongly enhanced oxygen ion transport through samarium-doped CeO2 nanopillars in nanocomposite films Citation Details In-Document Search This content will become publicly...

  6. 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...

  7. 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...

  8. Geothermal Reservoir Temperatures Estimated from the Oxygen Isotope...

    Open Energy Info (EERE)

    Geothermal Reservoir Temperatures Estimated from the Oxygen Isotope Compositions of Dissolved Sulfate and Water from Hot Springs and Shallow Drillholes Jump to: navigation, search...

  9. Geothermal reservoir temperatures estimated from the oxygen isotope...

    Open Energy Info (EERE)

    Geothermal reservoir temperatures estimated from the oxygen isotope compositions of dissolved sulfate and water from hot springs and shallow drillholes Jump to: navigation, search...

  10. 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.

  11. 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 Citation Details In-Document Search Title: Ultrafast kinetics subsequent to...

  12. Hydroxyl Radical is the Active Species in Photochemical DNA Strand Scission by Bis(peroxo)vanadium(V) Phenanthroline

    E-Print Network [OSTI]

    Chanfreau, Guillaume

    Hydroxyl Radical is the Active Species in Photochemical DNA Strand Scission by Bis-N-oxide (DMPO) as spin-traps for singlet oxygen and hydroxyl radical, respectively, implicated hydroxyl radical reactions were run on the same lane. These findings identify hydroxyl radical produced from

  13. 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 dispersant, plasticizer and binder provided superior cracking resistance compared to simple water, alcohol, or polyethylene glycol (PEG) based formulations. With a formulation employing castor oil as dispersant, isopropyl alcohol/mineral spirits as solvent, polyvinyl butyral as binder, and dibutyl phthalate/PEG as plasticizer, sintered SCFO membrane layers approximately 5 {micro}m thick with no apparent cracks were prepared using spin coating with several coats and sintering cycles. A similar but more viscous formulation applied by doctor blade gave a {approx} 10 {micro}m thick membrane layer in one coat, but with some apparent cracking. We demonstrated that the membrane layer could be densified while retaining porosity in the chemically identical support. This was accomplished by pre-sintering the support in air (1050 C), which coarsened the grain size and provided a relatively stable plate-shaped granular microstructure, followed by membrane layer fabrication with the highly-sinterable aerosol powder. Final densification was conducted by sintering in nitrogen ({approx}1100 C), which provided accelerated sintering rates and led to the desired layered perovskite phase content. In spite of these successes, low-temperature pressure-driven permeation testing with N2 showed that even the best membranes were not sufficiently defect free for high-temperature oxygen permeation testing. The source of these defects were not readily apparent from scanning electron microscopy, though incomplete or nonuniform membrane layer coverage from edge to edge of the support was probably one important factor.

  14. In vivo effect of inosine, pyruvate, and phosphate on the oxygen hemoglobin equilibrium curve and tissue oxygenation 

    E-Print Network [OSTI]

    Ross, Joe Nevill

    1974-01-01

    and Mixed Venous Blood Samples 2, 3-Diphosphoglycerate Determination M asurement of Mean Capillary Oxygen Tersion ( P-0 ) c 2 Measurement of P O Results 10 13 13 16 Discussion 25 Conclusion References Appendix I . Appendix II Appendix III... equilibrium curve pkI The r, egative log o. the hydrogen ion concentratior PO PCO P 02 a 2 P-0 a v 2 Partial pressure oi' oxygen Partial pressure of carbon dioxide Partial pressure of oxygen ir' arteria. l blood The oxygen partial pressure...

  15. On the oxygen abundance determination in HII regions: the problem of the line intensities -- oxygen abundance calibration

    E-Print Network [OSTI]

    L. S. Pilyugin

    2000-04-04

    The problem of the line intensities -- oxygen abundance calibration has been considered. We confirm the idea of McGaugh (1991) that the strong oxygen lines ([OII] 3727, 3729 and [OIII] 4959, 5007) contain the necessary information for determination of accurate abundances in low-metallicity (and may be also in high-metallicity) HII regions. It has been found that the excitation parameters p3 or p2 (which are defined here as contributions of the radiation in [OIII] 4959, 5007 lines and in [OII] 3727, 3729 lines to the "total" oxygen radiation respectively) allow to take into account the variations in R23 values among HII regions with a given oxygen abundance. Based on this fact a new way of the oxygen abundance determination in HII regions has been constructed and corresponding relations between line intensities and the oxygen abundance have been derived empirically using the available oxygen abundances determined via measurement of temperature-sensitive line ratios. In parallel a new R23 calibration has been derived on the base of recent data and compared to previous calibrations. For oxygen-rich HII regions the present R23 calibration is close to that of Edmunds and Pagel (1984): their calibration has the same slope but is shifted towards higher oxygen abundances by around 0.07 dex as compared to the present calibration.

  16. 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.

  17. Species Doubling and Chiral Lagrangians

    E-Print Network [OSTI]

    Michael Creutz; Michel Tytgat

    1996-05-15

    Coupling gauge fields to the chiral currents from an effective Lagrangian for pseudoscalar mesons naturally gives rise to a species doubling phenomenon similar to that seen with fermionic fields in lattice gauge theory.

  18. 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.

  19. Singlet oxygen luminescence detection with a fibre-coupled superconducting

    E-Print Network [OSTI]

    Greenaway, Alan

    Singlet oxygen luminescence detection with a fibre-coupled superconducting nanowire single luminescence detection Fibre-based singlet oxygen luminescence detection References Superconducting Detector, is an intermediate in many biological processes. We employ a superconducting nanowire single-photon detector (SNSPD

  20. Modeling In situ sediment oxygen demand in the Arroyo Colorado 

    E-Print Network [OSTI]

    Kasprzak, Kevin Ray

    2001-01-01

    and are targeted for rehabilitation under the Total Maximum Daily Load (TMDL) program. In some rivers, sediment oxygen demand (SOD) accounts for as much as 50% of the total oxygen depletion, making SOD a critical element in water quality modeling studies. SOD...

  1. 14. CARBON AND OXYGEN ISOTOPE ANALYSIS OF LAKE SEDIMENT CELLULOSE

    E-Print Network [OSTI]

    Edwards, Thomas W.D.

    14. CARBON AND OXYGEN ISOTOPE ANALYSIS OF LAKE SEDIMENT CELLULOSE: METHODS AND APPLICATIONS BRENT B and Environmental Sciences Wesleyan University, Middletown, CT USA 06459 Keywords: cellulose, lake sediment, oxygen of lake sediment cellulose is a recently developed paleolimnological approach that is gaining increasing

  2. Palladium-cobalt particles as oxygen-reduction electrocatalysts

    DOE Patents [OSTI]

    Adzic, Radoslav (East Setauket, NY); Huang, Tao (Manorville, NY)

    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.

  3. Breath is a mixture of nitrogen, oxygen, carbon dioxide, water

    E-Print Network [OSTI]

    12 SCIENCE Breath is a mixture of nitrogen, oxygen, carbon dioxide, water vapour, inert gases. On the basis of proton affinity, the major constituents of air and breath (nitrogen, oxygen, carbon dioxide, as the products of normal metabolism and those that have altered owing to disease, and are transported via

  4. E.L. Grossman Chapter 10 Oxygen Isotope Stratigraphy

    E-Print Network [OSTI]

    Grossman, Ethan L.

    E.L. Grossman Chapter 10 Oxygen Isotope Stratigraphy Abstract:Variations in the 18 O/16 O ratios isotope stratigraphy, however, is hampered by the lack of unaltered authigenic marine sediments. Chapter.6. Oxygen Isotope Stratigraphy 188 10.6.1. Cenozoic 188 10.6.2. Mesozoic 191 10.6.3. Paleozoic 193

  5. Alien Species and Evolution: The Evolutionary Ecology of Exotic Plants, Animals, Microbes and Interacting Native Species

    E-Print Network [OSTI]

    Nehrbass, Nana

    2005-01-01

    Review: Alien Species and Evolution: The EvolutionaryGermany George W. Cox. Alien Species and Evolution: TheRecycled, acid-free paper. Alien Species and Evolution leads

  6. Oxygen and organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen minimum zone (7001100 m)

    E-Print Network [OSTI]

    Levin, Lisa

    Oxygen and organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen) on the bathyal Pakistan margin, where sediments grade from fully laminated sediment at 700 m (0.12 mL LŔ1 O2 [5 m matter to generate abrupt faunal transitions on the Pakistan margin. & 2008 Elsevier Ltd. All rights

  7. Nanoparticulate-catalyzed oxygen transfer processes

    DOE Patents [OSTI]

    Hunt, Andrew T. (Atlanta, GA); Breitkopf, Richard C. (Dunwoody, GA)

    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.

  8. Activation of ROS/NF-{kappa}B and Ca{sup 2+}/CaM kinase II are necessary for VCAM-1 induction in IL-1{beta}-treated human tracheal smooth muscle cells

    SciTech Connect (OSTI)

    Luo, S.-F. [Department of Internal Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Chang, C.-C.; Lee, I-T. [Department of Physiology and Pharmacology, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Lee, C.-W. [Department of Nursing, Division of Basic Medical Sciences, Chang Gung Institute of Technology, Chia-Yi, Taiwan (China); Lin, W.-N. [Department of Physiology and Pharmacology, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Lin, C.-C. [Department of Anesthetics, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Yang, C.-M. [Department of Physiology and Pharmacology, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China)], E-mail: chuenmao@mail.cgu.edu.tw

    2009-05-15

    Histone acetylation regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) plays a critical role in the expression of inflammatory genes, such as vascular cell adhesion molecule-1 (VCAM-1). Oxidative processes have been shown to induce VCAM-1 expression. Here, we investigated the mechanisms underlying IL-1{beta}-induced VCAM-1 expression in human tracheal smooth muscle cells (HTSMCs). Our results showed that IL-1{beta} enhanced HTSMCs-monocyte adhesion through up-regulation of VCAM-1, which was inhibited by pretreatment with selective inhibitors of PKC{alpha} (Goe6976), c-Src (PP1), NADPH oxidase [diphenylene iodonium (DPI) and apocynin (APO)], intracellular calcium chelator (BAPTA/AM), PI-PLC (U73122), CaM (calmidazolium chloride), CaM kinase II (KN62), p300 (garcinol), NF-{kappa}B (Bay11-7082), HDAC (trichostatin A), and ROS scavenger [N-acetyl-L-cysteine (NAC)] or transfection with siRNAs of MyD88, PKC{alpha}, Src, p47{sup phox}, p300, and HDAC4. Moreover, IL-1{beta} stimulated NF-{kappa}B and CaMKII phosphorylation through MyD88-dependent PI-PLC/PKC{alpha}/c-Src/ROS and PI-PLC/Ca{sup 2+}/CaM pathways, respectively. Activation of NF-{kappa}B and CaMKII may eventually lead to the acetylation of histone residues and phosphorylation of histone deacetylases. These findings suggested that IL-1{beta} induced VCAM-1 expression via these multiple signaling pathways in HTSMCs. Blockade of these pathways may reduce monocyte adhesion via VCAM-1 suppression and attenuation of the inflammatory responses in airway diseases.

  9. A Selective, Cell-Permeable Optical Probe for Hydrogen Peroxide in Living Michelle C. Y. Chang, Arnd Pralle, Ehud Y. Isacoff, and Christopher J. Chang*,

    E-Print Network [OSTI]

    Pralle, Arnd

    A Selective, Cell-Permeable Optical Probe for Hydrogen Peroxide in Living Cells Michelle C. Y-mail: chrischang@berkeley.edu Hydrogen peroxide is a major reactive oxygen species (ROS) in living organisms-catalyzed condensation of 3-iodophenol and phthalic anhydride affords 3,6-diiodofluoran 1 in 25% yield.21 Palladium

  10. Massachusetts Endangered Species Act Regulations (Massachusetts)

    Broader source: Energy.gov [DOE]

    The regulations that accompany the Massachusetts Endangered Species Act list three categories of animals and plants in need of protection: endangered, threatened, and species of special concern....

  11. Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons in the ambient air of two

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons in the ambient air of two aromatic hydrocarbons, 17 nitrated PAHs (NPAHs) and 8 oxygenated PAHs (OPAHs) were carried out during hydrocarbons; Nitrated polycyclic aromatic hydrocarbons; Oxygenated polycyclic aromatic hydrocarbons

  12. 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.

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

    SciTech Connect (OSTI)

    Kojda, Danny [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin (Germany) [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin (Germany); Freie Universität Berlin, 14195 Berlin (Germany); Wallacher, Dirk; Hofmann, Tommy, E-mail: tommy.hofmann@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin (Germany)] [Helmholtz-Zentrum Berlin für 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 Universität Hamburg-Harburg, 21073 Hamburg (Germany)] [Technische Universität 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.

  14. Oxygen Enrichment in the Process and Chemical Industries 

    E-Print Network [OSTI]

    Milne, R. T.

    1984-01-01

    the efficiency of combustion processes. In a conventional ai r-fuel flame, combustion results from the collision of oxygen molecules wi th those 0f the fuel. The use 0f oxygen enrichment to increase the oxygen concentration in the fuel-air mixture... (Figure 3), which leads to improved heat transfer in the combustion zone. This results in a number of potential advantages: i. Fuel Savings At constant output the fuel firing rate may be reduced to compensate for the improved heat utilization...

  15. 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.

  16. 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.

  17. 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.

  18. Production of Ultra-Cold-Neutrons in Solid ?-Oxygen

    E-Print Network [OSTI]

    E. Gutsmiedl; A. Frei; F. Boehle; A. Maier; S. Paul; H. Schober; A. Orecchini

    2010-07-30

    Our recent neutron scattering measurements of phonons and magnons in solid \\alpha-oxygen have led us to a new understanding of the production mechanismen of ultra-cold-neutrons (UCN) in this super-thermal converter. The UCN production in solid \\alpha-oxygen is dominated by the excitation of phonons. The contribution of magnons to UCN production becomes only slightly important above E >10 meV and at E >4 meV. Solid \\alpha-oxygen is in comparison to solid deuterium less effcient in the down-scattering of thermal or cold neutrons into the UCN energy regime.

  19. A Kinetic Monte Carlo model for material aging: Simulations of second phase formation at Au/Bi{sub 2}Te{sub 3} junction in oxygen environments

    SciTech Connect (OSTI)

    Zhou, X. W., E-mail: xzhou@sandia.gov [Mechanics of Materials Department, Sandia National Laboratories, Livermore, California 94550 (United States); Yang, N. Y. C. [Energy Nanomaterials Department, Sandia National Laboratories, Livermore, California 94550 (United States)

    2014-03-14

    Electronic properties of semiconductor devices are sensitive to defects such as second phase precipitates, grain sizes, and voids. These defects can evolve over time especially under oxidation environments and it is therefore important to understand the resulting aging behavior in order for the reliable applications of devices. In this paper, we propose a kinetic Monte Carlo framework capable of simultaneous simulation of the evolution of second phases, precipitates, grain sizes, and voids in complicated systems involving many species including oxygen. This kinetic Monte Carlo model calculates the energy barriers of various events based directly on the experimental data. As a first step of our model implementation, we incorporate the second phase formation module in the parallel kinetic Monte Carlo codes SPPARKS. Selected aging simulations are performed to examine the formation of second phase precipitates at the eletroplated Au/Bi{sub 2}Te{sub 3} interface under oxygen and oxygen-free environments, and the results are compared with the corresponding experiments.

  20. Influence of oxygen pressure and aging on LaAlO{sub 3} films grown by pulsed laser deposition on SrTiO{sub 3} substrates

    SciTech Connect (OSTI)

    Park, Jihwey; Aeppli, Gabriel [London Centre for Nanotechnology, University College London, London WC1H 0AH (United Kingdom); Soh, Yeong-Ah, E-mail: yeongahsoh@gmail.com [London Centre for Nanotechnology, University College London, London WC1H 0AH (United Kingdom); Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom); David, Adrian; Lin, Weinan [Division of Physics and Applied Physics, Nanyang Technological University, Singapore 637371 (Singapore); Wu, Tom [Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia)

    2014-02-24

    The crystal structures of LaAlO{sub 3} films grown by pulsed laser deposition on SrTiO{sub 3} substrates at oxygen pressure of 10{sup ?3} millibars or 10{sup ?5} millibars, where kinetics of ablated species hardly depend on oxygen background pressure, are compared. Our results show that the interface between LaAlO{sub 3} and SrTiO{sub 3} is sharper when the oxygen pressure is lower. Over time, the formation of various crystalline phases is observed while the crystalline thickness of the LaAlO{sub 3} layer remains unchanged. X-ray scattering as well as atomic force microscopy measurements indicate three-dimensional growth of such phases, which appear to be fed from an amorphous capping layer present in as-grown samples.

  1. Seasonal and interannual oxygen variability on the Washington and Oregon continental shelves

    E-Print Network [OSTI]

    2015-01-01

    oxygen variability on the Washington and Oregon continentalin Juan de Fuca Canyon, Washington, Geophys. Res. Lett. ,oxygen ?uxes on the Washington shelf and slope: A comparison

  2. Microfluidic advantage : novel techniques for protein folding and oxygen control in cell cultures

    E-Print Network [OSTI]

    Polinkovsky, Mark E.; Polinkovsky, Mark E.

    2012-01-01

    Novel Techniques for Protein Folding and Oxygen Control inTemperature Jump System to Study Fast Protein FoldingNovel Techniques for Protein Folding and Oxygen Control in

  3. High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal...

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

    High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference...

  4. 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...

  5. Holocene hydrologic balance of tropical South America from oxygen isotopes of lake sediment opal, Venezuelan Andes

    E-Print Network [OSTI]

    Wolfe, Alexander P.

    Holocene hydrologic balance of tropical South America from oxygen isotopes of lake sediment opal.V. All rights reserved. Keywords: oxygen isotopes; biogenic opal; hydrologic balance; Holocene; Venezuela

  6. Laser spectroscopy and dynamics of transient species. Final progress report, June 1, 1986--May 31, 1996

    SciTech Connect (OSTI)

    Clouthier, D.J.

    1996-05-01

    This project involved the study of the spectroscopy and excited state dynamics of transient molecules, particularly sulfur- and/or oxygen-containing species. The identification and study of sulfur species is important in understanding their role in combustion processes, as sulfur compounds are often present in fuels. The oxygen-containing species chosen for study were new systems whose spectroscopy was only poorly documented. The major experimental techniques employed in this work were pyrolysis jet spectroscopy, intracavity dye laser spectroscopy and high-resolution Fourier transform infrared spectroscopy. Since many of the species had not been previously studied by laser techniques, much effort was devoted to determining methods for producing, identifying and studying them. We have been very successful in a number of cases and have developed some new experimental techniques. Lists of publications resulting from the work and graduate and postdoctoral students supported during this project are included at the end of this report. Summaries of the results of some specific aspects of the project are given below.

  7. Phosphorescent semiconductor nanocrystals and proteins for biological oxygen sensing

    E-Print Network [OSTI]

    McLaurin, Emily J. (Emily Jane)

    2011-01-01

    Oxygen is required for cellular respiration by all complex life making it a key metabolic profiling factor in biological systems. Tumors are defined by hypoxia (low pO2), which has been shown to influence response to ...

  8. Deciphering brain oxygenation and its change with age using phosphorescence

    E-Print Network [OSTI]

    Meunier, Michel

    for energy metabolism in every cell in the body. · The functioning of the brain is critically dependent #12;Oxygenation biomarkers · Average tissue pO2 · Spatial heterogeneity in tissue pO2 · pO2 gradient

  9. 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.

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

    DOE Patents [OSTI]

    Looney, Brian B. (Aiken, SC); Denham, Miles E. (Aiken, SC)

    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.

  11. 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.

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

    Broader source: Energy.gov [DOE]

    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.

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

    DOE Patents [OSTI]

    Staiger, Chad L. (Albuquerque, NM); Vaughn, Mark R. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM); Cornelius, Christopher J. (Blackburg, VA)

    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.

  14. 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...

  15. Titania may produce abiotic oxygen atmospheres on habitable exoplanets

    E-Print Network [OSTI]

    Narita, Norio; Masaoka, Shigeyuki; Kusakabe, Nobuhiko

    2015-01-01

    The search for habitable exoplanets in the Universe is actively ongoing in the field of astronomy. The biggest future milestone is to determine whether life exists on such habitable exoplanets. In that context, oxygen in the atmosphere has been considered strong evidence for the presence of photosynthetic organisms. In this paper, we show that a previously unconsidered photochemical mechanism by titanium(IV) oxide (titania) can produce abiotic oxygen from liquid water under near ultraviolet (NUV) lights on the surface of exoplanets. Titania works as a photocatalyst to dissociate liquid water in this process. This mechanism offers a different source of a possibility of abiotic oxygen in atmospheres of exoplanets from previously considered photodissociation of water vapor in upper atmospheres by extreme ultraviolet (XUV) light. Our order-of-magnitude estimation shows that possible amounts of oxygen produced by this abiotic mechanism can be comparable with or even more than that in the atmosphere of the current ...

  16. 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...

  17. Polycyclic Aromatic Hydrocarbons Orbiting HD 233517, an Evolved Oxygen-Rich Red Giant

    E-Print Network [OSTI]

    M. Jura; J. Bohac; B. Sargent; W. J. Forrest; J. Green; D. M. Watson; G. C. Sloan; F. Markwick-Kemper; C. H. Chen; J. Najita

    2005-12-14

    We report spectra obtained with the Spitzer Space Telescope in the 5 to 35 micron range of HD 233517, an evolved K2 III giant with circumstellar dust. At wavelengths longer than 13 microns, the flux is a smooth continuum that varies approximately as frequency to the -5/3 power. For wavelengths shorter than 13 microns, although the star is oxygen-rich, PAH features produced by carbon-rich species at 6.3 microns, 8.2 microns, 11.3 microns and 12.7 microns are detected along with likely broad silicate emission near 20 microns. These results can be explained if there is a passive, flared disk orbiting HD 233517. Our data support the hypothesis that organic molecules in orbiting disks may be synthesized in situ as well as being incorporated from the interstellar medium.

  18. 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.

  19. 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.

  20. Determination of carbon, nitrogen, and oxygen in high purity magnesium 

    E-Print Network [OSTI]

    Roche, Neil Gerard

    1981-01-01

    DETERMINATION OF CARBON, NITROGEN, AND OXYGEN IN HIGH PURITY MAGNESIUM A Thesis by NEIL GERARD ROCHE Submitted to the Graduate College of Texas A8cM University in partial i'ulfillment of the requirement for the degree of MASTER OF SCIENCE... December 1981 Major Subject: Chemistry DETERMINATION OF CARBON, NITROGEN, AND OXYGEN IN HIGH PURITY MAGNESIUM A Thesis by NEIL GERARD ROCHE Approved as to style and content by: E. A. Schweikert (Chairman of Committee) G. J. Bastiaans (Member) L...

  1. 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).

  2. 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.

  3. 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.

  4. Strain effects on oxygen transport in tetragonal zirconium dioxide

    SciTech Connect (OSTI)

    Xian-Ming Bai; Yongfeng Zhang; Michael R. Tonks

    2013-11-01

    Temperature accelerated dynamics and molecular dynamics simulations are used to investigate the strain effects on oxygen interstitial and vacancy migration in tetragonal zirconium dioxide. At zero external strain, the anisotropic migration mechanisms of oxygen defects are characterized. At non-zero strains, both the crystal structure and defect migration barriers are modified by strain. Under compressive strains, the defect migration barrier increases with the increasing strain for both interstitials and vacancies. The crystal structure transforms from a tetragonal to a nearly cubic fluorite structure. Accordingly, the defect migration becomes nearly isotropic. Under dilative strains, the migration barrier first decreases then increases with increasing strain for both types of defects. The tetragonal phase transforms to a lower symmetry structure that is close to the orthorhombic phase. In turn, the defect migration becomes highly anisotropic. Under both compressive and dilative strains, interstitials respond to strain more strongly than vacancies. At small dilative strains, an oxygen interstitial has comparable diffusivity to a vacancy, suggesting that both types of defects can contribute to oxygen transport, if they are present. Although currently no previous result is available to validate oxygen interstitial diffusion behavior, the trend of strain effects on oxygen vacancy diffusion is in good agreement with available experimental and theoretical studies in the literature.

  5. 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.

  6. 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 completes the vacancy to become a full ZnO molecule vacancy, which does not produce deep levels. Our results explain why ZnO finds use as an electrical detector for oxygen and for carbon containing gas molecules. They may also shed new light on photocatalytic uses of ZnO. It is suggested that similar surface phenomena may affect other semiconducting oxides.

  7. Direct Spectroscopic Observation of Fe(III)-Phenolate Complex Formed From the Reaction of Benzene With Peroxide Species on Fe/ZSM-5 At Room Temperature

    E-Print Network [OSTI]

    Li, Weixue

    Direct Spectroscopic Observation of Fe(III)-Phenolate Complex Formed From the Reaction of BenzeneVed: March 20, 2008 The reaction of benzene with the active oxygen species was studied by UV-visible diffuse as a precursor for phenol resins, fibers, dyestuffs, and medicine. The direct oxidation of benzene to phenol

  8. Production of Reactive Oxygen Species by Multipotent Stromal Cells/Mesenchymal Stem Cells Upon Exposure to Fas Ligand

    E-Print Network [OSTI]

    Rodrigues, Melanie

    Multipotent stromal cells (MSCs) can be differentiated into osteoblasts and chondrocytes, making these cells candidates to regenerate cranio-facial injuries and lesions in long bones. A major problem with cell replacement ...

  9. The role of reactive oxygen species and calcium in the interferon regulatory factor 3 mediated toll like receptor 4 signaling

    E-Print Network [OSTI]

    Jiang, Zhiyuan

    2007-01-01

    invading microorganisms by recognizing pathogen associatedpathogen associated molecular patterns (PAMPs), which are essential for the survival of the microorganism andpathogen associated molecular patterns (PAMPs), that are essential for the survival of the microorganism and

  10. Serotonin 5-HT2B Receptor Blockade Prevents Reactive Oxygen SpeciesInduced Cardiac Hypertrophy in Mice

    E-Print Network [OSTI]

    Boyer, Edmond

    hypertrophy, ie, angiotensin II and isoproterenol infusions in mice. Angiotensin II infusion for 14 days215505) prevented the increase in cardiac superoxide generation and hypertrophy. Similarly, infusion

  11. Comparison of species-specific oxygen isotope paleotemperature equations: Sensitivity analysis using planktonic foraminifera from the Cariaco Basin, Venezuela

    E-Print Network [OSTI]

    Meyers, Steven D.

    using planktonic foraminifera from the Cariaco Basin, Venezuela Katherine E. Wejnert a, , Robert C, Venezuela a b s t r a c ta r t i c l e i n f o Article history: Received 6 December 2011 Received in revised biweekly sediment trap samples collected in Cariaco Basin, Venezuela between 2003 and 2008. Sixteen

  12. The JET Hydrogen-Oxygen Recombination Sensor – A Safety Device for Hydrogen Isotope Processing Systems

    E-Print Network [OSTI]

    The JET Hydrogen-Oxygen Recombination Sensor – A Safety Device for Hydrogen Isotope Processing Systems

  13. 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.

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

    DOE Patents [OSTI]

    Schlichting, Mark R. (Chesterton, IN)

    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.

  15. Method and apparatus for producing oxygenates from hydrocarbons

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

    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.

  16. Photodissociation Dynamics of Halogen Oxide Species 

    E-Print Network [OSTI]

    Dooley, Kristin S.

    2010-07-14

    The focus of this dissertation is the study of the photodissociation dynamics of halogen oxide species (XO, X = Cl, Br, I). These radical species are known to be important in stratospheric and tropospheric ozone depletion ...

  17. Optimization of Oxygen Purity for Coal Conversion Energy Reduction 

    E-Print Network [OSTI]

    Baker, C. R.; Pike, R. A.

    1982-01-01

    or liquefaction. Gasification of coal is a partial oxidation process in which steam and oxygen are reacted with coal to produce a mixture of hydrogen and carbon monoxide plus a number of other components. This mixture has a heating value of about 300 Btu..., or hydrocarbon liquids. The synthesis gas mixture can also be converted by means of the water gas shift reaction to produce hydrogen Which, in turn, can be reacted with coal to form hydrocarbon liquids by direct liquefaction techniques. Oxygen is required...

  18. Species discrimination from a hyperspectral perspective

    E-Print Network [OSTI]

    Species discrimination from a hyperspectral perspective Md. Istiak Sobhan #12;Promoters: Prof. Dr University, the Netherlands #12;Species discrimination from a hyperspectral perspective Md. Istiak Sobhan in the auditorium of ITC, Enschede #12;Species discrimination from hyperspectral perspective © 2007 Md. Istiak

  19. eschweizerbartxxx Interactions between alien species and restoration

    E-Print Network [OSTI]

    Pace, Michael L.

    eschweizerbartxxx Interactions between alien species and restoration of large-river ecosystems-river ecosystems that are the subject of restoration efforts also typically are heavily invaded by alien species interactions that link alien species and river restoration. Most obviously, restoration may be aimed

  20. 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.

  1. cDNA microarray-based studies of thermal stress-induced bleaching in the Caribbean corals Montastraea faveolata and Acropora palmata

    E-Print Network [OSTI]

    DeSalvo, Michael Kenneth

    2010-01-01

    of ROS, reactive nitrogen species (RNS) can be formed (e.g.The collected detriments of ROS, RNS, and NO must invariablyto the action of ROS, RNS, and NO, we cannot downplay the

  2. Fiber-optic oxygen sensor using molybdenum chloride cluster luminescence

    E-Print Network [OSTI]

    Ghosh, Ruby N.

    been obtained, a range suitable for biological and automotive applications. The luminescence signal. S0003-6951 99 01445-X The quantitative detection of oxygen is important for industrial, automotive constant of 10 4 cm2 /s or a diffusion time of 1 s. PTMSP's mechanical properties, environmental stability

  3. 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.

  4. Methane Activation with Rhenium Catalysts. 1. Bidentate Oxygenated Ligands

    E-Print Network [OSTI]

    Goddard III, William A.

    Methane Activation with Rhenium Catalysts. 1. Bidentate Oxygenated Ligands Jason M. Gonzales, Jonas, California 90089 ReceiVed July 31, 2006 Trends in methane activation have been explored for rhenium complexes proceeds with methane activation through a barrier of less than 35 kcal mol-1 . Study

  5. 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.

  6. Characteristics of Knock in Hydrogen-Oxygen-Argon SI Engine

    SciTech Connect (OSTI)

    Killingsworth, N; Rapp, V; Flowers, D; Aceves, S; Chen, J; Dibble, R

    2010-02-23

    A promising approach for improving the efficiency of internal combustion engines is to employ a working fluid with a high specific heat ratio such as the noble gas argon. Moreover, all harmful emissions are eliminated when the intake charge is composed of oxygen, nonreactive argon, and hydrogen fuel. Previous research demonstrated indicated thermal efficiencies greater than 45% at 5.5 compression ratio in engines operating with hydrogen, oxygen, and argon. However, knock limits spark advance and increasing the efficiency further. Conditions under which knock occurs in such engines differs from typical gasoline fueled engines. In-cylinder temperatures using hydrogen-oxygen-argon are higher due to the high specific heat ratio and pressures are lower because of the low compression ratio. Better understanding of knock under these conditions can lead to operating strategies that inhibit knock and allow operation closer to the knock limit. In this work we compare knock with a hydrogen, oxygen, and argon mixture to that of air-gasoline mixtures in a variable compression ratio cooperative fuels research (CFR) engine. The focus is on stability of knocking phenomena, as well as, amplitude and frequency of the resulting pressure waves.

  7. 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.

  8. Fault Tolerant Oxygen Control of a Diesel Engine Air System

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fault Tolerant Oxygen Control of a Diesel Engine Air System Rainer Nitsche Matthias Bitzer control problem of a Diesel engine air system having a jammed Exhaust Gas Recirculation (EGR) valve of the air system. Keywords: Fault tolerant control, Diesel engine, Air system, Model-based trajectory

  9. Characterizing the Oxygen Isotopic Composition of Phosphate Sources

    E-Print Network [OSTI]

    Paytan, Adina

    phosphorite ore, particulate aerosols, detergents, leachates of vegetation, soil, animal feces, and wastewater treatment plant effluent. We found a considerable range of 18 Op values (from +8.4 to +24.9) for the various to the phosphorus (P) in phosphate (PO4) (4-7). The primary goal of this study is to characterize the oxygen

  10. An oxygen reduction electrocatalyst based on carbon nanotubegraphene complexes

    E-Print Network [OSTI]

    Pennycook, Steve

    such as platinum or its alloys are routinely used in fuel cells because of their high activity. Carbon alloys) for the oxygen reduction reaction (ORR) in acidic media for proton-exchange membrane fuel cells1, and designing catalysts with both optimal activity and stability for ORR in acidic solutions all remain

  11. Reaction Pathways for Oxygen Evolution Promoted by Cobalt Giuseppe Mattioli,*,

    E-Print Network [OSTI]

    Guidoni, Leonardo

    by such natural processes, the goal of artificial photosynthesis is to develop simplified but still efficient models in explicit water solution, we provide insight into the pathways for oxygen evolution of a cobalt routes to generate chemical fuels (e.g., H2) directly from sunlight by means of "artificial leafs",3,4 i

  12. High-temperature potentiometric oxygen sensor with internal reference

    DOE Patents [OSTI]

    Routbort, Jules L. (Hinsdale, IL); Singh, Dileep (Naperville, IL); Dutta, Prabir K. (Worthington, OH); Ramasamy, Ramamoorthy (North Royalton, OH); Spirig, John V. (Columbus, OH); Akbar, Sheikh (Hilliard, OH)

    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.

  13. OXYGEN BLOCK IN THE MAIN -STEM WILLAMETTE RIVER

    E-Print Network [OSTI]

    ^hly publicized run of spring-chinook salmon. Pollution of the Willamette River is a problem that has receivedOXYGEN BLOCK IN THE MAIN -STEM WILLAMETTE RIVER i.iiit' I'.iological Labordtory B R A tl Y OCT 9-STEM WILIA^TETTE RIVER By Frederic F. Fish In Charge, Western Fish-Cultural Investigations and Richard A

  14. IMPROVEMENTS IN MODELLING DISSOLVED OXYGEN IN ACTIVATED SLUDGE SYSTEMS

    E-Print Network [OSTI]

    Wells, Scott A.

    . Wells** *Technical University of Gdansk, Department of Environmental Engineering, ul. Narutowicza 11 the impact of reactor hydraulics and variable oxygen mass transfer on a predicted DO profile along the longitudinal axis of the activated sludge reactor. Many important parameters are influenced by the hydraulic

  15. INVESTIGATION OF OXYGEN REDUCTION MECHANISMS USING CATHODE MICROELECTRODES, PART II

    E-Print Network [OSTI]

    Yildiz, Bilge

    and alternatives are proposed for further investigation. INTRODUCTION The power of a solid oxide fuel cell (SOFC. Although oxygen re- duction at SOFC cathodes has been studied in the literature, a comprehensive and clear resistances and capacitances in the SOFC behavior. All implications presented in Refs. 2-7 have been based

  16. Oxygen adsorption on graphite and nanotubes P. Giannozzi,a)

    E-Print Network [OSTI]

    Giannozzi, Paolo

    Oxygen adsorption on graphite and nanotubes P. Giannozzi,a) R. Car, and G. Scoles Chemistry Department and Princeton Materials Institute, Princeton University, Princeton, New Jersey 08544 Received 29 in molecular form,6 with an estimated binding energy E 0.19 eV. This would be consistent with the well

  17. 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.

  18. 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.

  19. 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

  20. Oxygen: From Environment to Genes. The periodic occurrence of oxygen minima can powerfully influence organisms living in near

    E-Print Network [OSTI]

    ­ Humans and Hypoxia in the Ocean, spread and recovery of dead zones. 20. Martini Arostegui - Oxygen terrestrial use flows into nearshore ocean waters. These high-nutrient inputs fuel phytoplankton blooms increasingly anoxic, zones are not directly human-induced, but occur with variations in the winds that drive

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

    E-Print Network [OSTI]

    Shalish, Ilan

    , which energy position coincides with the position of the so called "green luminescence" in Zn on the energy required for decomposition and for the observed emission of lattice oxygen in the form of CO2 of the energy bands. Using surface photovoltage spectroscopy in ultra high vacuum, we monitored changes

  2. Summary -Procedure For Shutting Off The Oxygen Zone Valve 1. Implement RACE Call the Emergency Operator at 4-2012.

    E-Print Network [OSTI]

    Acton, Scott

    Summary - Procedure For Shutting Off The Oxygen Zone Valve 1. Implement RACE ­ Call the Emergency-cylinders for low oxygen needs and bag ventilated patients using E-cylinders. 4. Identify oxygen zone valve for the affected rooms/areas. 5. Turn off the flow of oxygen at the zone valve if the oxygen cannot be turned off

  3. Carolyn Penstein Ros Language Technologies Institute

    E-Print Network [OSTI]

    Murphy, Robert F.

    process does the steam undergo in the Turbines ? Student: condensation System: Steam undergoes Isentropic Expansion in a turbines that converts the heat energy of the steam into work by rotating the blades. What for use? Student: wtf!!! System: We should NOT use low quality steam in turbines as it condenses

  4. 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.

  5. Development, testing, and application of quantitative oxygenation imaging from magnetic susceptibility by MRI

    E-Print Network [OSTI]

    Fan, Audrey Peiwen

    2014-01-01

    The healthy brain consumes 20% of total oxygen used by the body under normal conditions. Continuous oxygen delivery to neural tissue is needed to maintain normal brain function and viability. Reliable measurements of brain ...

  6. In Situ Ambient Pressure X-ray Photoelectron Spectroscopy Studies of Lithium-Oxygen Redox Reactions

    E-Print Network [OSTI]

    Lu, Yi-chun

    The lack of fundamental understanding of the oxygen reduction and oxygen evolution in nonaqueous electrolytes significantly hinders the development of rechargeable lithium-air batteries. Here we employ a solid-state ...

  7. Electronic structure of perovskite oxide surfaces at elevated temperatures and its correlation with oxygen reduction reactivity

    E-Print Network [OSTI]

    Chen, Yan, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    The objective is to understand the origin of the local oxygen reduction reaction (ORR) activity on the basis of the local electronic structure at the surface of transition metal oxides at elevated temperatures and in oxygen ...

  8. Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons in the ambient air of two

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons in the ambient air of two;2 Abstract The size distribution of polycyclic aromatic hydrocarbons (PAHs) and PAH derivatives of compounds. Keywords: Polycyclic aromatic hydrocarbons; Nitrated polycyclic aromatic hydrocarbons; Oxygenated

  9. Direct Electrolysis of Molten Lunar Regolith for the Production of Oxygen and Metals on the Moon

    E-Print Network [OSTI]

    Sirk, Aislinn H.

    The feasibility of producing oxygen by direct electrolysis of the molten lunar regolith at 1600 C was investigated and the generation of usable oxygen gas at the anode and concomitant production of iron and silicon at the ...

  10. A finite difference model for predicting sediment oxygen demand in streams 

    E-Print Network [OSTI]

    Charbonnet, Danielle Andrea

    2003-01-01

    Sediment oxygen demand (SOD) is a significant part of the dissolved oxygen budget in waterways, comprising up to 50% in some systems. It, therefore, has the potential of having a significant impact on the environment. ...

  11. Phase-based regional oxygen metabolism in magnetic resonance imaging at high field

    E-Print Network [OSTI]

    Fan, Audrey Peiwen

    2010-01-01

    Venous oxygen saturation (Yv) in cerebral veins and the cerebral metabolic rate of oxygen (CMRO?) are important indicators for brain function and disease. Phase-susceptibility measurements in magnetic resonance imaging ...

  12. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    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...

  13. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    designing remediation strategies for such pollutants. Phylogenetic analyses place this new species within the deeply divergent order Gleobacterales, a branch that diverged...

  14. 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.

  15. 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.

  16. Simultaneous analysis of oxygenated and nitrated polycylic aromatic hydrocarbons on standard reference material 1649a (urban dust) and

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Simultaneous analysis of oxygenated and nitrated polycylic aromatic hydrocarbons on standard nitrated polycylic aromatic hydrocarbons (NPAHs) and 9 oxygenated polycylic aromatic hydrocarbons (OPAHs aromatic hydrocarbons; Nitrated polycyclic aromatic hydrocarbons; Oxygenated polycyclic aromatic

  17. Beryllium, Lithium and Oxygen Abundances in F-type Stars

    E-Print Network [OSTI]

    R. J. Garcia Lopez; M. C. Dominguez Herrera; M. R. Perez de Taoro; C. Casares; J. L. Rasilla; R. Rebolo; C. Allende Prieto

    1997-10-07

    Beryllium and oxygen abundances have been derived in a sample of F-type field stars for which lithium abundances had been measured previously, with the aim of obtaining observational constraints to discriminate between the different mixing mechanisms proposed. Mixing associated with the transport of angular momentum in the stellar interior and internal gravity waves within the framework of rotating evolutionary models, appear to be promising ways to explain the observations.

  18. Diurnal patterns of denitrification, oxygen consumption and nitrous oxide production in rivers measured

    E-Print Network [OSTI]

    Seitzinger, Sybil

    Diurnal patterns of denitrification, oxygen consumption and nitrous oxide production in rivers Dame, Notre Dame, IN, U.S.A. SUMMARY 1. Denitrification, net oxygen consumption and net nitrous oxide. Denitrification, oxygen consumption and N2O flux were measured based on net changes in dissolved gas

  19. 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.

  20. Explosion Hazard from a Propellant-Tank Breach in Liquid Hydrogen-Oxygen Rockets

    E-Print Network [OSTI]

    Muratov, Cyrill

    Explosion Hazard from a Propellant-Tank Breach in Liquid Hydrogen-Oxygen Rockets Viatcheslav Osipov liquid hydrogen-oxygen rockets during launch accidents is presented.The assessmentis based on the analysis of the data of purposefulrupture experiments with liquid oxygen and hydrogen tanks

  1. Faunal responses to oxygen gradients on the Pakistan margin: A comparison of foraminiferans, macrofauna and megafauna

    E-Print Network [OSTI]

    Levin, Lisa

    Faunal responses to oxygen gradients on the Pakistan margin: A comparison of foraminiferans Oxygen minimum zone Benthos Arabian Sea Biodiversity Deep sea a b s t r a c t The Pakistan Margin where oxygen levels were lowest. The rarity of larger animals between 300 and 700 m on the Pakistan

  2. The Role of Silicon Interstitials in the Formation of Boron-Oxygen Defects in Crystalline Silicon

    E-Print Network [OSTI]

    The Role of Silicon Interstitials in the Formation of Boron-Oxygen Defects in Crystalline Silicon@ise.fhg.de Keywords: crystalline silicon, Czochralski, boron-oxygen defect, silicon interstitial Abstract. Oxygen-rich crystalline silicon materials doped with boron are plagued by the presence of a well-known carrier

  3. Supplemental Oxygen and Mountaineer Death Rates on Everest and K2

    E-Print Network [OSTI]

    Huey, Raymond B.

    Supplemental Oxygen and Mountaineer Death Rates on Everest and K2 To the Editor: The use of supplemental oxygen by Hima- layan mountaineers has been debated for more than 8 de- cades.1 Although sometimes- veal an impact of supplemental oxygen on survival because de- scending mountaineers are often near

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

    DOE Patents [OSTI]

    Cassano, Anthony A. (Allentown, PA)

    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.

  5. Wireless Harsh-Environment Oxygen Sensors D.W. Greve,1,2

    E-Print Network [OSTI]

    Greve, David.W.

    pollution. In oxy-fuel combustion of coal, separated oxygen is used so that the exhaust is nearly pure. INTRODUCTION Oxygen sensors are used in many combustion processes is order to improve efficiency and reduce the development of wireless oxygen sensors suitable for placement in the harsh environment of the combustion

  6. Kinetic fractionation of carbon and oxygen isotopes during hydration of carbon dioxide

    E-Print Network [OSTI]

    Zeebe, Richard E.

    Kinetic fractionation of carbon and oxygen isotopes during hydration of carbon dioxide Richard E the inorganic hydration of carbon dioxide (CO2) in aqueous solution cause reduced stable carbon and oxygen of the carbon and oxygen kinetic isotope fractionation (KIF) during hydration of CO2. Here I use transition

  7. Oxygen production and carbon sequestration in an upwelling coastal Burke Hales,1

    E-Print Network [OSTI]

    Oxygen production and carbon sequestration in an upwelling coastal margin Burke Hales,1 Lee Karp), Oxygen production and carbon sequestration in an upwelling coastal margin, Global Biogeochem. Cycles, 20 of particulate organic carbon (POC) and dissolved O2 during the upwelling season off the Oregon coast. Oxygen

  8. Doped Graphene as a Material for Oxygen Reduction Reaction in Hydrogen Fuel Cells: A Computational Study

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Doped Graphene as a Material for Oxygen Reduction Reaction in Hydrogen Fuel Cells: A Computational fuel cells for oxygen reduction at the cathode. In an attempt to find a cheap yet efficient catalyst in graphene are promising candidates for the use in fuel cell cathodes for oxygen reduction reaction (ORR). We

  9. Degradation of Staphylococcus aureus bacteria by neutral oxygen atoms

    SciTech Connect (OSTI)

    Cvelbar, U.; Mozetic, M. [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Hauptman, N.; Klanjsek-Gunde, M. [National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia)

    2009-11-15

    The degradation of Staphylococcus aureus bacteria during treatment with neutral oxygen atoms was monitored by scanning electron microscopy. Experiments were performed in an afterglow chamber made from borosilicate glass. The source of oxygen atoms was remote inductively coupled radiofrequency oxygen plasma. The density of atoms at the samples was 8x10{sup 20} m{sup -3}. The treatment was performed at room temperature. The first effect was the removal of dried capsule. Capsule on exposed parts of bacteria was removed after receiving the dose of 6x10{sup 23} at./m{sup 2}, while the parts of capsule filling the gaps between bacteria were removed after receiving the dose of 2.4x10{sup 24} m{sup -2}. After removing the capsule, degradation continued as etching of bacterial cell wall. The etching was rather nonuniform as holes with diameter of several 10 nm were observed. The cell wall was removed after receiving the dose of about 7x10{sup 24} m{sup -2}. The etching probabilities were about 2x10{sup -5} for the capsule and 2x10{sup -6} for the cell wall. The results were explained by different compositions of capsule and the cell wall.

  10. The solar oxygen crisis: Probably not the last word

    E-Print Network [OSTI]

    H. Socas-Navarro A. A. Norton

    2007-03-26

    In this work we present support for recent claims that advocate a downward revision of the solar oxygen abundance. Our analysis employs spatially-resolved spectro-polarimetric observations including the \\FeI lines at 6302 \\AA and the \\OI infrared triplet around 7774 \\AA in the quiet Sun. We used the \\FeI lines to reconstruct the three-dimensional thermal and magnetic structure of the atmosphere. The simultaneous \\OI observations were then employed to determine the abundance of oxygen at each pixel, using both LTE and non-LTE (NLTE) approaches to the radiative transfer. In this manner, we obtain values of \\lgEO=8.63 (NLTE) and 8.93 (LTE) dex. We find an unsettling fluctuation of the oxygen abundance over the field of view. This is likely an artifact indicating that, even with this relatively refined strategy, important physical ingredients are still missing in the picture. By examining the spatial distribution of the abundance, we estimate realistic confidence limits of approximately 0.1 dex.

  11. 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.

  12. SPECIES COMPOSITION OF INDUSTRIAL TRAWL LANDINGS

    E-Print Network [OSTI]

    SPECIES COMPOSITION OF INDUSTRIAL TRAWL LANDINGS IN NEW ENGLAND, 1957 Marine Biological Laboratory;#12;ABSTRACT This report presents data on the species composition of the industrial trawl fish catch landed OF TABLES Page Table 1. 1957 landings and number of trips of industrial trawl fish vessels at Pt. Judith

  13. 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.

  14. 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.

  15. Eukaryotic microbes, species recognition and the geographic limits of species: examples

    E-Print Network [OSTI]

    Eukaryotic microbes, species recognition and the geographic limits of species: examples from of eukaryotic microbes, the Fungi. We show that inferred geographic range of a fungal species depends upon structure (Finlay & Fenchel 2004). Finlay & Fenchel's claim of global ranges for eukaryotic microbes echoes

  16. 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.

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

    SciTech Connect (OSTI)

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

    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.

  18. 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.

  19. Effect of surface strain on oxygen adsorption on Zr (0001) surface

    SciTech Connect (OSTI)

    Wang, Xing [Univ. of Wisconsin-Madison, Madison, WI (United States). Dept. of Engineering Physics; Khafizov, Marat [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Szlufarska, Izabela [Univ. of Wisconsin-Madison, Madison, WI (United States). Dept. of Engineering Physics; Univ. of Wisconsin-Madison, Madison, WI (United States). Dept. of Materials Science and Engineering

    2014-02-01

    The effect of surface strain on oxygen adsorption on Zr (0 0 0 1) surface is investigated by density functional theory (DFT) calculations. It is demonstrated that both surface strain and interactions between oxygen adsorbates influence the adsorption process. Oxygen binding to zirconium becomes stronger as the strain changes from compressive to tensile. When oxygen coverage is low and the oxygen interactions are negligible, surface face-centered cubic sites are the most stable for O binding. At high coverage and under compression, octahedral sites between second and third Zr layers become most favorable because the interactions between adsorbates are weakened by positive charge screening. Calculations with both single-layer adsorption model and multiple-layer adsorption model demonstrate that compressive strain at the Zr/oxide interface will provide a thermodynamic driving force for oxygen to incorporate from the surface into the bulk of Zr, while binding oxygen to the Zr surface will be easier when tensile strain is applied.

  20. 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).

  1. Method for providing oxygen ion vacancies in lanthanide oxides

    DOE Patents [OSTI]

    Kay, D. Alan R. (4305 Lakeshore Rd., Burlington, CA); Wilson, William G. (820 Harden Dr., Pittsburgh, PA 15229)

    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.

  2. 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.

  3. 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.

  4. 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)

  5. Defining viral species: making taxonomy useful

    E-Print Network [OSTI]

    Peterson, A. Townsend

    2014-07-23

    Virus taxonomy at present is best characterized as a categorization of convenience, without a firm basis in the principles of evolutionary biology. Specifically, virus species definitions appear to depend more on tradition and popular opinion among...

  6. Effect of Variable Surrounding on Species Creation

    E-Print Network [OSTI]

    Aleksandra Nowicka; Artur Duda; Miroslaw R. Dudek

    2002-07-08

    We construct a model of speciation from evolution in an ecosystem consisting of a limited amount of energy recources. The species posses genetic information, which is inherited according to the rules of the Penna model of genetic evolution. The increase in number of the individuals of each species depends on the quality of their genotypes and the available energy resources. The decrease in number of the individuals results from the genetic death or reaching the maximum age by the individual. The amount of energy resources is represented by a solution of the differential logistic equation, where the growth rate of the amount of the energy resources has been modified to include the number of individuals from all species in the ecosystem under consideration. We observe that small evolutionary changes of the inherited genetic information lead to spontaneous bursts of the evolutionary activity when many new species may appear in a short period.

  7. Irreversibility and uncertainty in species valuation

    E-Print Network [OSTI]

    Brooks, Eileen L.

    1994-01-01

    This paper incorporates an option value into deforestation policy analysis. Similar to an option value in finance, the option value here reflects the advantage to delaying irreversible species extinction until more information ...

  8. 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.

  9. COMPUTATIONAL RESOURCES FOR BIOFUEL FEEDSTOCK SPECIES

    SciTech Connect (OSTI)

    Buell, Carol Robin [Michigan State University; Childs, Kevin L [Michigan State University

    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/).

  10. OXYGEN ISOTOPE MEASUREMENTS OF A RARE MURCHISON TYPE A CAI AND ITS RIM. J. E. P. , J. I. Simon2

    E-Print Network [OSTI]

    to oxygen isotope zoning profiles measured from CAIs in other chondrites. MUM-1 Petrography: The petrography

  11. Type Ia supernovae from exploding oxygen-neon white dwarfs

    E-Print Network [OSTI]

    Marquardt, Kai S; Ruiter, Ashley J; Seitenzahl, Ivo R; Ohlmann, Sebastian T; Kromer, Markus; Pakmor, Ruediger; Roepke, Friedrich K

    2015-01-01

    The progenitor problem of Type Ia supernovae (SNe Ia) is still unsolved. Most of these events are thought to be explosions of carbon-oxygen (CO) white dwarfs (WDs), but for many of the explosion scenarios, particularly those involving the externally triggered detonation of a sub-Chandrasekhar mass WD (sub-M Ch WD), there is also a possibility of having an oxygen-neon (ONe) WD as progenitor. We simulate detonations of ONe WDs and calculate synthetic observables from these models. The results are compared with detonations in CO WDs of similar mass and observational data of SNe Ia. We perform hydrodynamic explosion simulations of detonations in initially hydrostatic ONe WDs for a range of masses below the Chandrasekhar mass (M Ch), followed by detailed nucleosynthetic postprocessing with a 384-isotope nuclear reaction network. The results are used to calculate synthetic spectra and light curves, which are then compared with observations of SNe Ia. We also perform binary evolution calculations to determine the nu...

  12. 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 advancements offer significant reductions in power requirements, which would improve plant efficiency and economics for the oxygen-fired technology. The second phase consisted of pilot-scale testing followed by a refined performance and economic evaluation of the O{sub 2} fired CFB concept. As a part of this workscope, ALSTOM modified its 3 MW{sub th} (9.9 MMBtu/hr) Multiuse Test Facility (MTF) pilot plant to operate with O{sub 2}/CO{sub 2} mixtures of up to 70 percent O{sub 2} by volume. Tests were conducted with coal and petroleum coke. The test objectives were to determine the impacts of oxygen firing on heat transfer, bed dynamics, potential agglomeration, and gaseous and particulate emissions. The test data results were used to refine the design, performance, costs, and economic models developed in Phase-I for the O{sub 2}-fired CFB with CO{sub 2} capture. Nsakala, Liljedahl, and Turek reported results from this study in 2004. ALSTOM identified several items needing further investigation in preparation for large scale demonstration of the oxygen-fired CFB concept, namely: (1) Operation and performance of the moving bed heat exchanger (MBHE) to avoid recarbonation and also for cost savings compared to the standard bubbling fluid bed heat exchanger (FBHE); (2) Performance of the back-end flash dryer absorber (FDA) for sulfur capture under high CO{sub 2}/high moisture flue gas environment using calcined limestone in the fly ash and using fresh commercial lime directly in the FDA; (3) Determination of the effect of recarbonation on fouling in the convective pass; (4) Assessment of the impact of oxygen firing on the mercury, other trace elements, and volatile organic compound (VOC) emissions; and (5) Develop a proposal-level oxygen-fired retrofit design for a relatively small existing CFB steam power plant in preparation for a large-scale demonstration of the O{sub 2} fired CFB concept. Hence, ALSTOM responded to a DOE Solicitation to address all these issues with further O{sub 2} fired MTF pilot testing and a subsequent retrofit design study of oxygen firing and CO{s

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

    DOE Patents [OSTI]

    Sindorf, John F. (Pewaukee, WI)

    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.

  14. Charge-state and element-resolved ion energies in the cathodic arc plasma from composite AlCr cathodes in argon, nitrogen and oxygen atmospheres

    E-Print Network [OSTI]

    Franz, Robert; Anders, André

    2014-01-01

    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 Cr$^{2+}$ ions were dominating in Ar and N$_2$ and Cr$^{+}$ in O$_2$ 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 mainly thermalised. In addition to the positively charged metal and gas ions, negatively charged oxygen an...

  15. 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.

  16. 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.

  17. 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.

  18. 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. (Center de Recherches Metallurgiques, Liege (Belgium))

    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.

  19. 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.

  20. Table 10. U.S. Refiner Oxygenated Motor Gasoline Prices by...

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

    AdministrationPetroleum Marketing Annual 1999 Table 10. U.S. Refiner Oxygenated Motor Gasoline Prices by Grade and Sales Type (Cents per Gallon Excluding Taxes) Year Month...

  1. 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.

  2. Modeling and Control of High-Velocity Oxygen-Fuel (HVOF) Thermal Spray: A Tutorial Review

    E-Print Network [OSTI]

    Li, Mingheng; Christofides, Panagiotis D.

    2009-01-01

    Fluid Dynamics Analysis of a Wire- Feed, High-Velocity Oxygen Fuel (Fluid Dynamic Modeling of Gas Flow Charac- teristics in a High-Velocity Oxy-Fuel

  3. Oxygen-resistant hydrogenases and methods for designing and making same

    DOE Patents [OSTI]

    King, Paul (Golden, CO); Ghirardi, Maria L (Lakewood, CO); Seibert, Michael (Lakewood, CO)

    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.

  4. Anomalous expansion of the copper-apical-oxygen distance in supercondu...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Anomalous expansion of the copper-apical-oxygen distance in superconducting cuprate bilayers Citation Details In-Document Search Title: Anomalous expansion of the...

  5. 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.

  6. 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.

  7. Processing Argo OXYGEN data at the DAC level Version 1.3

    E-Print Network [OSTI]

    Lherminier, Pascale

    that all countries deploying floats equipped with oxygen sensors document the data and metadata related............................................................................... 4 3.2 "SENSOR" metadata............................................................................. 14 4.2 "SENSOR" metadata

  8. 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.

  9. Constraining bubble dynamics and mixing with dissolved gases: Implications for productivity measurements by oxygen mass balance

    E-Print Network [OSTI]

    Hamme, Roberta C

    2006-01-01

    Implications for productivity measurements by oxygen masszone. Because the productivity measurement in the mixedproductivity estimates from continuous O 2 /Ar ratio measurements

  10. 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.

  11. Oxygen-Dependent Morphogenesis of Modern Clumped Photosynthetic Mats and Implications for the Archean Stromatolite Record

    E-Print Network [OSTI]

    Sim, Min Sub

    Some modern filamentous oxygenic photosynthetic bacteria (cyanobacteria) form macroscopic tufts, laminated cones and ridges that are very similar to some Archean and Proterozoic stromatolites. However, it remains unclear ...

  12. The effect of an evaporation suppressant upon the liquid film oxygen transfer coefficient 

    E-Print Network [OSTI]

    Amad, Mohamad Towfic

    1967-01-01

    by organisms in a lake and the quantity of oxygen diffusion through the air-water interface were determined and the results were verified by field measurements. It was shown that the oxygen uptake rate of organisms in a body of water can be measured... diffusion. 3. To derive an expression to predict the minimum dissolved oxygen concentration during the critical night period for a lake o" pond treated with "Aquasave". The ~sco e of this research has been to determine the oxygen transfer coefficient...

  13. 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

  14. Species interactions differ in their genetic robustness

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

    Chubiz, Lon M. [Univ. of Missouri - St. Louis, St. Louis, MO (United States); Granger, Brian R. [Boston Univ., MA (United States); Segre, Daniel [Boston Univ., MA (United States); Harcombe, William R. [Univ. of Minnesota, St. Paul, MN (United States)

    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.

  15. 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 180–240 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.

  16. 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 BiFeO?, 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 Ca˛? for Bił? cation. We found that by increasing the substitution, the in-plane orbital bands of Feł? 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 BiFeO? system.« less

  17. 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.

  18. Lithium-Beryllium-Boron and Oxygen in the early Galaxy

    E-Print Network [OSTI]

    Elisabeth Vangioni-Flam; Michel Casse

    2000-11-24

    Oxygen is a much better evolutionary index than iron to follow the history of Lithium-Beryllium-Boron (LiBeB) since it is the main producer of these light elements at least in the early Galaxy. The O-Fe relation is crucial to the determination of the exact physical process responsible for the LiBeB production. Calculated nucleosynthetic yields of massive stars, estimates of the energy cost of Be production, and above all recent observations reported in this meeting seem to favor a mechanism in which fast nuclei enriched into He, C and O arising from supernovae are accelerated in superbubbles and fragment on H and He in the interstellar medium.

  19. Metallicity of the intergalactic medium using pixel statistics: IV. Oxygen

    E-Print Network [OSTI]

    Anthony Aguirre; Corey Dow-Hygelund; Joop Schaye; Tom Theuns

    2008-07-21

    We have studied the abundance of oxygen in the IGM by analyzing OVI, CIV, SiIV, and HI pixel optical depths derived from a set of high-quality VLT and Keck spectra of 17 QSOs at 2.1 ~ 0.2. Consistent results are obtained by similarly comparing OVI to HI or OVI to SiIV optical depth ratios to simulation values, and also by directly ionization-correcting OVI optical depths as function of HI optical depths into [O/H] as a function of density. Subdividing the sample reveals no evidence for evolution, but low- and high-density samples are inconsistent, suggesting either density-dependence of [O/C] or -- more likely -- prevalence of collisionally-ionized gas at high density.

  20. Detailed Characterization of Lubricant-Derived Ash-Related Species...

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

    Characterization of Lubricant-Derived Ash-Related Species in Diesel Exhaust and Aftertreatment Systems Detailed Characterization of Lubricant-Derived Ash-Related Species in Diesel...

  1. Roles of plasma-generated vacuum-ultraviolet photons and oxygen radicals in damaging nanoporous low-k films

    SciTech Connect (OSTI)

    Lee, Joe; Graves, David B. [Department of Chemical Engineering, University of California, Berkeley, California 94720 (United States)

    2013-07-15

    One important class of low-k materials used as interconnect dielectrics employs methyl groups added to nanoporous SiO{sub 2} matrices. These carbon-doped oxide materials are known to be susceptible to damage from plasma species during various stages of plasma processing. Two key active species generated in O{sub 2} plasma are oxygen (O) radicals and vacuum-ultraviolet (VUV) photons. These species are known to cause carbon loss, resulting in damaging increases in dielectric constant throughout the film. However, the mechanisms through which this damage is incurred are poorly understood. By capping the substrate in different ways during plasma exposure, it is possible to expose films to either photons alone or O atoms alone. The authors report measurements of damage induced by VUV photons only, O radicals only, and the combination of O radicals and photons. Through HF stripping, they note that carbon extraction from photons and from radicals yields different outcomes; the profile of carbon concentration within the modified region is different for each case. Damage from photons alone can be modeled and model predictions are in good agreement with measurements. Damage from O atoms alone can only be modeled if it is assumed that the near-surface region has a significantly reduced diffusivity compared to the bulk of the film. Experiment and model agree that both photons alone and O radicals alone damage the material by removing carbon. When radicals and photons are present simultaneously during plasma exposure, however, more C removal appears to be occurring in the model than experimentally observed. Remarkably, if only radicals are exposed to the film after short (10-30 s) plasma exposures, very little additional damage is incurred during this radical-only exposure. The most straightforward interpretation of these results appears to be that photons combine synergistically with radicals in the pores to narrow the pores, thereby reducing film diffusivity in the C-poor, plasma-damaged regions.

  2. Modification of Gold Catalysis withModification of Gold Catalysis with Aluminum Phosphate for OxygenAluminum Phosphate for Oxygen--Reduction ReactionReduction Reaction

    E-Print Network [OSTI]

    Park, Byungwoo

    (PEMFC + DMFC) General MotorsPanasonic Power Source * PEMFC: proton exchange membrane fuel cell DMFC) H+ Oxygen or Air Ecat Hydrogen (PEMFC) (DMFC) Carbon Dioxide Water CatalystsCatalysts Membrane

  3. 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.

  4. Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

    SciTech Connect (OSTI)

    Morrin, Shane, E-mail: shane.morrin@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Lettieri, Paola, E-mail: p.lettieri@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Chapman, Chris, E-mail: chris.chapman@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Taylor, Richard, E-mail: richard.taylor@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom)

    2014-01-15

    Highlights: • We investigate gaseous sulphur species whilst gasifying sulphur-enriched wood pellets. • Experiments performed using a two stage fluid bed gasifier – plasma converter process. • Notable SO{sub 2} and relatively low COS levels were identified. • Oxygen-rich regions of the bed are believed to facilitate SO{sub 2}, with a delayed release. • Gas phase reducing regions above the bed would facilitate more prompt COS generation. - Abstract: Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO{sub 2} and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO{sub 2}’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO{sub 2} was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO{sub 2} generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.

  5. Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production

    DOE Patents [OSTI]

    Jujasz, Albert J. (North Olmsted, OH); Burkhart, James A. (Olmsted Falls, OH); Greenberg, Ralph (New York, NY)

    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.

  6. Ascorbate dynamics and oxygen consumption during arousal from hibernation in Arctic ground squirrels

    E-Print Network [OSTI]

    Drew, Kelly L.

    at the time of peak O2 consumption and peak plasma urate production. The ascor- bate decrease didAscorbate dynamics and oxygen consumption during arousal from hibernation in Arctic ground and oxygen consumption during arousal from hibernation in Arctic ground squirrels. Am J Physiol Regulatory

  7. Proceedings of IEEE Sensors 2003 Fiber Optic Oxygen Sensor for Power Plant Applications

    E-Print Network [OSTI]

    Ghosh, Ruby N.

    807 Proceedings of IEEE Sensors 2003 Paper 22-2 Fiber Optic Oxygen Sensor for Power Plant for power plant applications. The sensor utilizes quenching of the bright red fluorescence from inorganic. Motivation Combustion processes in power plants require the correct mix of fuel and oxygen to maximize

  8. Boundaries of the Peruvian Oxygen Minimum Zone shaped by coherent mesoscale dynamics

    E-Print Network [OSTI]

    Bettencourt, Joăo H; García, Emilio Hernández; Montes, Ivonne; Sudre, Joël; Dewitte, Boris; Paulmier, Aurélien; Garçon, Véronique

    2015-01-01

    Dissolved oxygen in sea water is a major factor affecting marine habitats and biogeochemical cycles. Oceanic zones with oxygen deficits represent significant portions of the area and volume of the oceans and are thought to be expanding. The Peruvian oxygen minimum zone is one of the most pronounced and lies in a region of strong mesoscale activity in the form of vortices and frontal regions, whose effect in the dynamics of the oxygen minimum zone is largely unknown. Here, we study this issue from a modeling approach and a Lagrangian point of view, using a coupled physical-biogeochemical simulation of the Peruvian oxygen minimum zone and finite-size Lyapunov exponent fields to understand the link between mesoscale dynamics and oxygen variations. Our results show that, at depths between 380 and 600 meters, mesoscale structures have a relevant dual role. First, their mean positions and paths delimit and maintain the oxygen minimum zone boundaries. Second, their high frequency fluctuations entrain oxygen across t...

  9. The obligation to surface periodically and replenish oxygen stores limits the underwater foraging capacity of marine

    E-Print Network [OSTI]

    Burns, Jennifer M.

    , but also aids in conserving water and energy during terrestrial fasts (Ortiz et al., 1978; Costa and Ortiz with animal size and age. In adults, total body oxygen stores are proportional to body mass (Mb; Kooyman, 1989 animals have higher mass-specific metabolic rates and lower mass-specific total body oxygen stores

  10. Carbon dioxide and oxygen fluxes in the Southern Ocean: Mechanisms of interannual variability

    E-Print Network [OSTI]

    Follows, Mick

    Carbon dioxide and oxygen fluxes in the Southern Ocean: Mechanisms of interannual variability A) to highlight the importance of convective mixing in inducing anomalous air-sea fluxes of carbon dioxide (2007), Carbon dioxide and oxygen fluxes in the Southern Ocean: Mechanisms of interannual variability

  11. The performance of PEM fuel cells fed with oxygen through the free-convection mode

    E-Print Network [OSTI]

    The performance of PEM fuel cells fed with oxygen through the free-convection mode Pei-Wen Li; accepted 27 September 2002 Abstract The feasibility and restrictions of feeding oxygen to a PEM fuel cell at the cathode surface, which can be viewed in terms of the relationship of the fuel cell current density

  12. A reactor for high-temperature pyrolysis and oxygen isotopic analysis of cellulose via induction heating

    E-Print Network [OSTI]

    Evans, Michael N.

    A reactor for high-temperature pyrolysis and oxygen isotopic analysis of cellulose via induction and theory to recommend pyrolysis at temperatures above 14508C to minimize memory and fractionation effects of producing pyrolysis conditions for the analysis of oxygen and deuterium isotopic compositions of organic

  13. Hydrogen passivation and activation of oxygen complexes in silicon S. N. Rashkeev,a)

    E-Print Network [OSTI]

    Pantelides, Sokrates T.

    Hydrogen passivation and activation of oxygen complexes in silicon S. N. Rashkeev,a) M. Di Ventra-principles calculations in terms of which we describe the role of hydrogen in passivating or activating oxygen complexes activity of the cluster. Furthermore, the addition of a hydrogen atom in the core structure of thermal

  14. Oxygen isotope records of goethite from ferricrete deposits indicate regionally varying Holocene climate change in

    E-Print Network [OSTI]

    Hren, Michael

    Oxygen isotope records of goethite from ferricrete deposits indicate regionally varying Holocene isotopes of goethite from ferricrete deposits were measured from both northern and southern Rocky Mountain in oxygen isotope values of 14 C-dated goethites in the northern Rocky Mountains suggests a regional

  15. Hydrogen absorption characteristics of oxygen-stabilized rare-earth iron intermetallic compounds

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hydrogen absorption characteristics of oxygen-stabilized rare-earth iron intermetallic compounds M Abstract. -- The thermal behavior of oxygen-stabilized RjFegO^-hydrogen (R = Y, Dy, Ho) systems was studied decade to the study of the hydrogenation characte- ristics of a variety of intermetallic compounds, our

  16. Polycyclic Aromatic Hydrocarbons (PAHs), nitrated PAHs and oxygenated PAHs in ambient air of the

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Polycyclic Aromatic Hydrocarbons (PAHs), nitrated PAHs and oxygenated PAHs in ambient air + particle phases) of 16 polycyclic aromatic hydrocarbons (PAHs), 17 nitrated PAHs (NPAHs) and 9 oxygenated when (before or during the sampling) the OPAHs are formed. Keywords: Polycyclic aromatic hydrocarbons

  17. Production of Organic Oxygenates in the Partial Oxidation of Methane in a Silent Electric Discharge Reactor

    E-Print Network [OSTI]

    Mallinson, Richard

    Production of Organic Oxygenates in the Partial Oxidation of Methane in a Silent Electric Discharge to convert methane into useful products such as higher hydrocarbons, synthesis gas, and organic oxygenate is important for a process to have commercial potential. Thus, this study examines the effect methane

  18. 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.

  19. A climatology-based quality control procedure for profiling float oxygen data

    E-Print Network [OSTI]

    Riser, Stephen C.

    A climatology-based quality control procedure for profiling float oxygen data Yuichiro Takeshita,1 to a climatology derived from ship-based bottle and CTD data [Wong et al., 2003; Bohme and Send, 2005; Owens for profiling float oxygen data based on comparing float data to a monthly climatology and therefore driving

  20. Uranium in iron formations and the rise of atmospheric oxygen C.A. Partin a,

    E-Print Network [OSTI]

    Konhauser, Kurt

    Uranium in iron formations and the rise of atmospheric oxygen C.A. Partin a, , S.V. Lalonde b , N Paleoproterozoic Geochemical uranium cycle The concept of the Great Oxidation Event (GOE), during which atmospheric oxygenation through the record of uranium (U) concentrations in iron formations (IF). Just as IF are important

  1. Lung deflation and oxygen pulse in COPD: Results from the NETT randomized trial*

    E-Print Network [OSTI]

    Lung deflation and oxygen pulse in COPD: Results from the NETT randomized trial* Carolyn E. Come a July 2011 Available online 16 August 2011 KEYWORDS Cardiac function; Hyperinflation; Lung volume function. We examined whether lung deflation improves oxygen pulse, a surrogate marker of stroke volume

  2. Unified picture of the oxygen isotope effect in cuprate superconductors Ho-kwang Mao

    E-Print Network [OSTI]

    Wu, Zhigang

    Unified picture of the oxygen isotope effect in cuprate superconductors Ho-kwang Mao Xiao-Jia Chen, see: Reprints www.pnas.org/misc/reprints.shtml To order reprints, see: Notes: #12;Unified picture present a unified picture of the oxygen isotope effect in cuprate superconductors based on a phonon

  3. SHORT COMMUNICATION Metabolic oxygen consumption measurement with a single-cell

    E-Print Network [OSTI]

    Brenner, David Jonathan

    SHORT COMMUNICATION Metabolic oxygen consumption measurement with a single-cell biosensor after Ó Springer-Verlag Berlin Heidelberg 2014 Abstract A noninvasive, self-referencing biosensor Microbeam II end station. A single-cell oxygen consumption measurement has been conducted with this type

  4. Alkaline Microfluidic Hydrogen-Oxygen Fuel Cell as a Cathode Characterization Platform

    E-Print Network [OSTI]

    Kenis, Paul J. A.

    Alkaline Microfluidic Hydrogen-Oxygen Fuel Cell as a Cathode Characterization Platform Fikile R on an alkaline microfluidic fuel cell for catalyst and electrode characterization. Its constantly refreshing investigated and the dual effects of enhanced oxygen reduction reaction activity and improved ionic

  5. 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.

  6. Stress-Induced Nitrogen and Oxygen Segregation and Complexing Investigated by High Resolution Synchrotron FTIR

    E-Print Network [OSTI]

    . Ciszek4 1 . Dept. of Materials Science & Eng., North Carolina State University, NC 2 . Dept. of Materials, CA 4 : National Renewable Energy Laboratory, CO Abstract: Nitrogen doped Czochralski (N-CZ) and Float variations and the defect distributions revealed by an Oxygen Precipitate Profiler (OPP), and oxygen

  7. Triple oxygen isotope variations in sedimentary rocks Naomi E. Levin a,

    E-Print Network [OSTI]

    . However, recent oxygen isotope measurements of terrestrial rocks, minerals and waters also reveal common for various equilibrium and kinetic mechanisms. Here we pres- ent triple oxygen isotope data on sedimentary; Pack and Herwartz, 2014), but they are gener- ally overlooked in analysis of terrestrial rocks

  8. Holocene precipitation seasonality captured by a dual hydrogen and oxygen isotope approach at Steel Lake, Minnesota

    E-Print Network [OSTI]

    Hu, Feng Sheng

    Holocene precipitation seasonality captured by a dual hydrogen and oxygen isotope approach at SteelMenocal Keywords: seasonal precipitation middle Holocene oxygen isotopes hydrogen isotopes forest­prairie boundary midcontinental North America. However, neither the climatic driver nor the seasonal character of precipitation

  9. Predicting species invasions using ecological niche modeling

    E-Print Network [OSTI]

    Peterson, A. Townsend; Vieglais, David A.

    2001-05-01

    ) and commission (including niche space not ,lctually occupied by the 'pecies). Each algorithm for modeling specIes' ecological niches involves a specific com binatiol1 of errors of omission ,md commission. A rel.ltively new approach, called the (;enetic...

  10. Explaining species distribution patterns through hierarchical modeling

    E-Print Network [OSTI]

    Gelfand, Alan E.; Silander, John A., Jr.; Wu, Shanshan; Latimer, Andrew; Lewis, Paul O.; Rebelo, Anthony G.; Holder, Mark T.

    2006-01-01

    ; 000 cells total for the region). We report on results for 40 species of a owering plant family Proteaceae (of about 330 in the CFR) for a de ned subregion. Using a Bayesian framework, we develop a two stage, spatially explicit, hierar- chical logistic...

  11. Attenuation of wall disturbances in an electron cyclotron resonance oxygen–argon 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.

  12. 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.

  13. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOE Patents [OSTI]

    Bitensky, Mark W. (Boston, MA); Yoshida, Tatsuro (Newton, MA)

    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.

  14. On the relationship between auroral and nebular oxygen line intensities in spectra of HII regions

    E-Print Network [OSTI]

    L. S. Pilyugin

    2005-04-18

    We investigate relationships between observed auroral and nebular oxygen line fluxes in spectra of HII regions. We find a relation that is metallicity-dependent at low metallicities, but becomes independent of metallicity (within the uncertainties of the available data) above 12+logO/H ~ 8.25, i.e. there is one-to-one correspondance (the ff - relation) between auroral and nebular oxygen line fluxes in spectra of high-metallicity HII regions. The ff - relation allows one to estimate the flux in the auroral line from strong oxygen line measurements. This solves the problem of the electron temperature (and, consequently, abundance) determination in high-metallicity HII regions. The ff - relation confirms the basic idea of the empirical method, proposed by Pagel et al. (1979) a qurter of a century ago, that the oxygen abundance in HII region can be estimated from the strong oxygen lines measurements only.

  15. Oxygen abundances in dwarf irregular galaxies and the metallicity - luminosity relationship

    E-Print Network [OSTI]

    L. S. Pilyugin

    2001-05-21

    The low-luminosity dwarf irregular galaxies are considered. The oxygen abundances in HII regions of dwarf irregular galaxies were recalculated from published spectra through the recently suggested P - method. It has been found that the metallicity of low-luminosity dwarf irregular galaxies, with a few exceptions, correlates well with galaxy luminosity. The dispersion of oxygen abundances around the metallicity - luminosity relationship increases with decreasing of galaxy luminosity, as was found by Richer and McCall (1995). No relationship between the oxygen abundance and the absolute magnitude in the blue band for irregular galaxies obtained by Hidalgo-Gamez and Olofsson (1998) can be explained by the large uncertainties in the oxygen abundances derived through the Te - method, that in turn can be explained by the large uncertainties in the measurements of the strengths of the weak oxygen line [OIII]4363 used in the Te - method.

  16. Accounting for species taxonomy improves distribution models Aidin Niamir a

    E-Print Network [OSTI]

    models, multispecies models, species distribution models Abstract: The use of species atlas data of species distribution models. Using atlas data, two taxonomically enhanced datasets were created for 356. Enhancement of atlas data by excluding irrelevant absences based on species taxonomy significantly improved

  17. 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); Gérard, J.-C.; Hubert, B. [Laboratory for Planetary and Atmospheric Physics (LPAP), University of Ličge, Ličge (Belgium); Jehin, E.; Decock, A. [Origines Cosmologiques et Astrophysiques (ORCA), University of Ličge (Belgium); Hutsemékers, D. [Extragalactic Astrophysics and Space Observations (EASO), University of Ličge (Belgium); Manfroid, J., E-mail: B.Hubert@ulg.ac.be [High Energy Astrophysics Group (GAPHE), University of Ličge (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 (630 nm) and green (557.7 nm) 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.

  18. Standard Test Method for Determination of Uranium, Oxygen to Uranium (O/U), and Oxygen to Metal (O/M) in Sintered Uranium Dioxide and Gadolinia-Uranium Dioxide Pellets by Atmospheric Equilibration

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    Standard Test Method for Determination of Uranium, Oxygen to Uranium (O/U), and Oxygen to Metal (O/M) in Sintered Uranium Dioxide and Gadolinia-Uranium Dioxide Pellets by Atmospheric Equilibration

  19. 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.

  20. Oxygen enrichment in carbon-rich planetary nebulae

    E-Print Network [OSTI]

    Delgado-Inglada, Gloria; Peimbert, Manuel; Stasi?ska, Gra?yna; Morisset, Christophe

    2015-01-01

    We study the relation between the chemical composition and the type of dust present in a group of 20 Galactic planetary nebulae (PNe) that have high quality optical and infrared spectra. The optical spectra are used, together with the best available ionization correction factors, to calculate the abundances of Ar, C, Cl, He, N, Ne, and O relative to H. The infrared spectra are used to classify the PNe in two groups depending on whether the observed dust features are representative of oxygen-rich or carbon-rich environments. The sample contains one object from the halo, eight from the bulge, and eleven from the local disc. We compare their chemical abundances with nucleosynthesis model predictions and with the ones obtained in seven Galactic H II regions of the solar neighbourhood. We find evidence of O enrichment (by $\\sim$ 0.3 dex) in all but one of the PNe with carbon-rich dust (CRD). Our analysis shows that Ar, and especially Cl, are the best metallicity indicators of the progenitors of PNe. There is a tig...

  1. 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.

  2. 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.

  3. Oxygen sensor for monitoring gas mixtures containing hydrocarbons

    DOE Patents [OSTI]

    Ruka, Roswell J. (Pittsburgh, PA); Basel, Richard A. (Pittsburgh, PA)

    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.

  4. Thickness Dependence of Oxygen Reduction Reaction Kinetics on Strontium-Substituted Lanthanum Manganese Perovskite Thin-Film Microelectrodes

    E-Print Network [OSTI]

    la O’, G. J.

    Oxygen reduction reaction (ORR) kinetics was investigated on dense La?.?Sr?.?MnO? microelectrodes as a function of temperature and microelectrode thickness using electrochemical impedance spectroscopy. The surface oxygen ...

  5. PHYSICAL REVIEW B 84, 245206 (2011) First-principles study of band gap engineering via oxygen vacancy doping

    E-Print Network [OSTI]

    Rappe, Andrew M.

    2011-01-01

    vacancies can play a beneficial role. For example, in solid oxide fuel cells, oxygen vacancies enable for photovoltaic applications.6­8 Despite the technological relevance of oxygen vacancies in ferroelectric solutions are fundamentally interesting and technologically important. However, experimental

  6. 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.

  7. On the oxygen abundance determination in HII regions: High - metallicity regions

    E-Print Network [OSTI]

    L. S. Pilyugin

    2001-01-25

    This is our second paper devoted to the problem of line intensity - oxygen abundance calibration starting from the idea of McGaugh (1991) that the strong oxygen lines contain the necessary information to determine accurate abundances in HII regions. The high-metallicity HII regions are considered. A relation of the type O/H=f(P,R23) between oxygen abundance and the value of abundance index R23 introduced by Pagel et al. (1979) and the excitation parameter P (which is defined here as the contribution of the radiation in [OIII]4959,5007 lines to the "total" oxygen radiation) has been derived empirically using the available oxygen abundances determined via measurement of a temperature-sensitive line ratio [OIII]4959,5007/[OIII]4363 (Te - method). By comparing oxygen abundances derived with the Te - method and those derived with the suggested relations (P - method), it was found that the precision of oxygen abundance determination with the P - method is around 0.1 dex and is comparable to that of the Te - method. A relation of the type Te=f(P,R23) between electron temperature and the values of abundance index R23 and the excitation parameter P was derived empirically using the available electron temperatures determined via measurement of temperature-sensitive line ratios. The mean difference between electron temperatures derived through the Te=f(P,23 relation and determined via measurement of the temperature-sensitive line ratio is around 500K.

  8. 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-Chien; Yang, Ping

    2013-01-28

    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 MO4x- anions 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 MO4- (M = Mn, Tc, Re) are evaluated for the first time by nonresonant inelastic X-ray scattering, X-ray absorption spectroscopy using fluorescence and transmission (via a scanning transmission X-ray microscope), and time-dependent density functional theory. The results suggest that moving from Group 6 to Group 7 or down the triads increases M-O e* (pi*) mixing; for example, it more than doubles in ReO4- relative to CrO42-. Mixing in the t(2)* orbitals (sigma* + pi*) remains relatively constant within the same Group, but increases on moving from Group 6 to Group 7. These unexpected changes in orbital energy and composition for formally isoelectronic tetraoxometalates are evaluated in terms of periodic trends in d orbital energy and radial extension.

  9. Intragrain oxygen isotope zoning in titanite by SIMS: Cooling rates and fluid infiltration along the Carthage-Colton Mylonite

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Intragrain oxygen isotope zoning in titanite by SIMS: Cooling rates and fluid infiltration along studies because of the ubiquity of oxygen- bearing minerals and the dependence of mineral 18 O/16 O ratios on temperature and fluid composi- tion. In this study, subtle intragrain oxygen isotope zoning in titanite

  10. PII S0016-7037(98)00212-9 Measurement of oxygen fugacities under reducing conditions: Non-Nernstian behavior of

    E-Print Network [OSTI]

    -Nernstian behavior of Y2O3-doped zirconia oxygen sensors R. A. MENDYBAEV,1 J. R. BECKETT,2, * E. STOLPER,2 and L procedure is presented for the use of a Y2O3-stabilized zirconia (YSZ) oxygen sensor in 1 atm gas involved are adequately char- acterized. Yttrium oxide- (YSZ) and calcium oxide-doped (CSZ) zirconia oxygen

  11. The principal function of the cardiopulmonary system is the matching of oxygen and carbon dioxide transport to the

    E-Print Network [OSTI]

    Bennett, Albert F.

    The principal function of the cardiopulmonary system is the matching of oxygen and carbon dioxide (fH), systemic blood flow (Q . sys), rate of oxygen consumption (V . O) and rate of carbon dioxide transport to the metabolic requirements of different tissues. Increased oxygen demands (V . O), for example

  12. Removing oxygen from a solvent extractant in an uranium recovery process

    DOE Patents [OSTI]

    Hurst, Fred J. (Oak Ridge, TN); Brown, Gilbert M. (Knoxville, TN); Posey, Franz A. (Concord, TN)

    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.

  13. 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.

  14. Roles of Oxygen and Water Vapor in the Oxidation of Halogen Terminated Ge(111) Surfaces

    SciTech Connect (OSTI)

    Sun, Shiyu; /Stanford U., Phys. Dept.; Sun, Yun; Liu, Zhi; Lee, Dong-Ick; Pianette, Piero; /SLAC, SSRL

    2006-12-18

    The initial stage of the oxidation of Cl and Br terminated Ge(111) surfaces is studied using photoelectron spectroscopy. The authors perform controlled experiments to differentiate the effects of different factors in oxidation, and find that water vapor and oxygen play different roles. Water vapor effectively replaces the halogen termination layers with the hydroxyl group, but does not oxidize the surfaces further. In contrast, little oxidation is observed for Cl and Br terminated surfaces with dry oxygen alone. However, with the help of water vapor, oxygen oxidizes the surface by breaking the Ge-Ge back bonds instead of changing the termination layer.

  15. 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.

  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 Nation’s 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. Catalytic Synthesis of Oxygenates: Mechanisms, Catalysts and Controlling Characteristics

    SciTech Connect (OSTI)

    Kamil Klier; Richard G. Herman

    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 Br�������¸nsted 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 blending octane No. of 105, and can replace aromatics in liquid fuels.

  18. Interdependence of tetrapyrrole metabolism, the generation of oxidative stress and the mitigative oxidative stress response

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

    Busch, Andrea W.U.; Montgomery, Beronda L.

    2015-04-01

    Tetrapyrroles are involved in light harvesting and light perception, electron-transfer reactions, and as co-factors for key enzymes and sensory proteins. Under conditions in which cells exhibit stress-induced imbalances of photosynthetic reactions, or light absorption exceeds the ability of the cell to use photoexcitation energy in synthesis reactions, redox imbalance can occur in photosynthetic cells. Such conditions can lead to the generation of reactive oxygen species (ROS) associated with alterations in tetrapyrrole homeostasis. ROS accumulation can result in cellular damage and detrimental effects on organismal fitness, or ROS molecules can serve as signals to induce a protective or damage-mitigating oxidative stressmore »signaling response in cells. Induced oxidative stress responses include tetrapyrrole-dependent and -independent mechanisms for mitigating ROS generation and/or accumulation. Thus, tetrapyrroles can be contributors to oxidative stress, but are also essential in the oxidative stress response to protect cells by contributing to detoxification of ROS. In this review, we highlight the interconnection and interdependence of tetrapyrrole metabolism with the occurrence of oxidative stress and protective oxidative stress signaling responses in photosynthetic organisms.« less

  19. Indirect Gas Species Monitoring Using Tunable Diode Lasers

    DOE Patents [OSTI]

    Von Drasek, William A. (Oak Forest, IL); Saucedo, Victor M. (Willowbrook, IL)

    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.

  20. Negative Valve Overlap Reforming Chemistry in Low-Oxygen Environments

    SciTech Connect (OSTI)

    Szybist, James P [ORNL] [ORNL; Steeper, Richard R. [Sandia National Laboratories (SNL)] [Sandia National Laboratories (SNL); Splitter, Derek A [ORNL] [ORNL; Kalaskar, Vickey B [ORNL] [ORNL; Pihl, Josh A [ORNL] [ORNL; Daw, C Stuart [ORNL] [ORNL

    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.

  1. Development and Testing of a Portable Multi-Channel Depth-Resolved Near Infrared Spectroscopy System for Lower Leg Tissue Oxygenation Monitoring

    E-Print Network [OSTI]

    Kostic, Marko N.

    2013-01-01

    The level of oxygen saturation in the reservoir should bereservoir for porcine or bovine blood storage, ex vivo porcine tissue sample, oxygen saturation

  2. SYSTEMATICS The Field Cricket Gryllus assimilis and Two New Sister Species

    E-Print Network [OSTI]

    Gray, David A.

    for species with supposed transcontinental distributions must be resolved. One such species, Gryllus assimilis

  3. Dynamic Monte Carlo Simulations of the Oxygen Electroreduction Reaction on a Bimetallic Surface 

    E-Print Network [OSTI]

    Wood, Adam; Balbuena, Perla

    2006-07-11

    Platinum and platinum alloy surfaces are used as catalysts to promote the reduction of oxygen, one of the reactions used to generate electrical energy in low temperature fuel cells, which are sought as promissory clean power sources...

  4. Defect analysis and excitons diffusion in undoped homoepitaxial diamond films after polishing and oxygen

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and oxygen plasma etching Pierre-Nicolas Volpe*1 , Pierre Muret1 , Franck Omnes1 , Jocelyn Achard2 , François) growth sectors. Meanwhile, it * Corresponding author; e-mail: pierre

  5. Theoretical studies of transition metal surfaces as electrocatalysts for oxygen electroreduction 

    E-Print Network [OSTI]

    Lamas, Eduardo J.

    2007-09-17

    In the last few years the quest towards a hydrogen based economy has intensified interest for effective and less expensive catalysts for fuel cell applications. Due to its slow kinetics, alternative catalysts for the oxygen ...

  6. Biologically enhanced cathode design for improved capacity and cycle life for lithium-oxygen batteries

    E-Print Network [OSTI]

    Oh, Dahyun

    Lithium-oxygen batteries have a great potential to enhance the gravimetric energy density of fully packaged batteries by two to three times that of lithium ion cells. Recent studies have focused on finding stable electrolytes ...

  7. Control of Fuel Cell Breathing: Initial Results on the Oxygen Starvation Problem

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Hydrogen Water Gas Difusion Layers Flow Fields & Current Collectors H2 Proton Electron Water Oxygen from wind, water, and sun, or reformed hydrocarbon fuel will help reduce our dependency on fossil fuels

  8. Effects of low oxygen culture on pluripotent stem cell differentiation and teratoma formation

    E-Print Network [OSTI]

    Millman, Jeffrey Robert

    2011-01-01

    Pluripotent stem cells (PSC) hold promise for the study of embryonic development and the treatment of many diseases. Most pluripotent cell research is performed in incubators with a gas-phase oxygen partial pressure (p02) ...

  9. 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.

  10. Microprocessor Based Combustion Monitoring and Control Systems Utilizing in Situ Opacity, Oxygen and CO Measurement 

    E-Print Network [OSTI]

    Molloy, R. C.

    1981-01-01

    , self-diagnostics, field programmable memory, and improved operator interface. By measuring the products of combustion utilizing the latest In Situ Opacity, Oxygen, and CO Monitoring technology, the fuel air mixture ratio of industrial fuel burning...

  11. Oxygen and Opacity Stack Emission Monitoring Systems To Optimize Combustion Efficiency and Meet EPA Requirements 

    E-Print Network [OSTI]

    Molloy, R. C.

    1980-01-01

    The combustion efficiency of industrial fuel burning equipment can be optimized through the use of oxygen and opacity stack emission monitoring systems. By providing the operator with the means to obtain accurate, continuous, dynamic feedback...

  12. Comparison between different oxygen adsorption mechanisms for the catalytic oxidation of CO on a surface

    E-Print Network [OSTI]

    Ojeda, C

    2011-01-01

    We study by kinetic Monte Carlo simulations the dynamic behavior of a Ziff-Gulari-Barshad (ZGB) model for the catalytic oxidation of CO on a surface. It is well known that the ZGB model presents a continuous transition between an oxygen poisoned state and a reactive state that it is not observed in nature. Based on some experimental results that indicate that the oxygen atoms move away from each other upon dissociation at the surface, we modify the standard ZGB model by changing the entrance mechanism of the oxygen molecule. We study three different ways in which the oxygen atoms can be adsorbed at the surface such that the nonphysical continuous phase transition disappears. We calculate the phase diagram for the three cases and study the effects of including a CO desorption mechanism.

  13. 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.

  14. Computational mass transfer moduling of flow through a photocatalytic oxygen generator

    E-Print Network [OSTI]

    Köksal, Erin (Erin Sevim)

    2008-01-01

    A self-contained, portable oxygen generator would be extraordinarily useful across a broad spectrum of industries. Both safety and energy-efficiency could be enhanced tremendously in fields such as coal mining, commercial ...

  15. Seasonal and interannual oxygen variability on the Washington and Oregon continental shelves

    E-Print Network [OSTI]

    2014-01-01

    nutrient-rich, low-oxygen offshore water is upwelled ontothe majority of the offshore casts were taken during theon the Washington coast, offshore of Grays Harbor (46 N–47

  16. Seasonal and interannual oxygen variability on the Washington and Oregon continental shelves

    E-Print Network [OSTI]

    2015-01-01

    nutrient-rich, low-oxygen offshore water is upwelled ontothe majority of the offshore casts were taken during theon the Washington coast, offshore of Grays Harbor (46 N–47

  17. Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina

    E-Print Network [OSTI]

    French, Katherine L. (Katherine Louise)

    2015-01-01

    Tracing the evolution of Earth's redox history is one of the great challenges of geobiology and geochemistry. The accumulation of photosynthetically derived oxygen transformed the redox state of Earth's surface environments, ...

  18. MECHANISM OF OXYGEN ACTIVATION AND HYDROXYLATION BY THE AROMATIC AMINO ACID HYDROXYLASES 

    E-Print Network [OSTI]

    Pavon, Jorge A.

    2010-07-14

    The aromatic amino acid hydroxylases phenylalanine hydroxylase (PheH), tyrosine hydroxylase (TyrH) and tryptophan hydroxylase (TrpH) utilize tetrahydropterin and molecular oxygen to catalyze aromatic hydroxylation. All three enzymes have similar...

  19. Turbulent Oxygen Flames in Type Ia Supernovae A. J. Aspden1

    E-Print Network [OSTI]

    Bell, John B.

    distance behind the carbon flame. However, for Da16 > 1, turbulence enhances heat transfer and drives layer, which we shall refer to as an oxygen "flame", is broadened and islands of nearly isothermal

  20. Sulfur and Oxygen Isotope Analysis of Sulfate at Micromole Levels Using a Pyrolysis Technique in a

    E-Print Network [OSTI]

    Alexander, Becky

    Sulfur and Oxygen Isotope Analysis of Sulfate at Micromole Levels Using a Pyrolysis Technique sample. The technique takes advantage of the easy pyrolysis of Ag2SO4 to SO2, O2, and Ag metal

  1. CROSSED BEAM REACTIVE SCATTERING OF OXYGEN ATOMS AND SURFACE SCATTERING STUDIES OF GASEOUS CONDENSATION

    E-Print Network [OSTI]

    Sibener, S.J.

    2010-01-01

    F. 0( D,) Production When dilute oxygen-helium gas mixturesoxygen-helium mixture for maximizing Of D ) production. D Ihelium mixtures (12S torr total pressure, 145 watts I The genera­ and have observed atomic hydrogen production.

  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. Oceanic nutrient and oxygen transports and bounds on export production during the World Ocean Circulation Experiment

    E-Print Network [OSTI]

    Wunsch, Carl

    Oceanic nutrient and oxygen transports and bounds on export production during the World Ocean about 100 m). Because of correlations between errors, the export production becomes significant when cycling; 4863 Oceanography: Biological and Chemical: Sedimentation; KEYWORDS: export production, nutrient

  4. 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.

  5. In Situ CO, Oxygen, and Opacity Measurement for Optimizing Combustion Control System Performance 

    E-Print Network [OSTI]

    Molloy, R. C.

    1982-01-01

    detailed review of the latest state-of-the-art In Situ measurement techniques is provided, including: gas filter correlation spectroscopy (CO), zirconium oxide fuel cell (oxygen), and glass fiber optics based transmissometers (opacity). Recent...

  6. 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.

  7. Effect of oxygen potential on high temperature crack growth in alloy 617

    E-Print Network [OSTI]

    Benz, Julian K

    2009-01-01

    The effect of oxygen partial pressure on crack growth rates in Alloy 617 has been studied using both static and fatigue loading at 650°C. Tests were conducted at a constant stress intensity factor, K, for static loading ...

  8. Structural design of a lunar lander spacecraft for the Texas space grant regolith oxygen production experiment 

    E-Print Network [OSTI]

    Baccus, Ronald Kregg

    1996-01-01

    The focus of this research is the determination of a structural design for the lunar lander spacecraft currently being developed by the Texas Space Grant Consortium to transport a regolith oxygen production experiment to the surface of the moon...

  9. Size Influence on the Oxygen Reduction Reaction Activity and Instability of Supported Pt Nanoparticles

    E-Print Network [OSTI]

    Sheng, Wenchao

    Size-dependent oxygen reduction reaction activity (ORR) and instability of Pt nanoparticles is of great importance in proton exchange membrane fuel cell applications. In this study, the size-dependence of ORR activity on ...

  10. RESPIRATION RATES AND LOW-OXYGEN TOLERANCE LIMITS IN SKIPJACK TUNA, KATSUWONUS PELAMIS

    E-Print Network [OSTI]

    RESPIRATION RATES AND LOW-OXYGEN TOLERANCE LIMITS IN SKIPJACK TUNA, KATSUWONUS PELAMIS REGINALD M of voluntarily active skipjack tuna, Katsuwonus pelamis, at 23°_24° C were measured in the laboratory from

  11. Fundamental understanding and materials design approaches for lithium-oxygen electrochemical energy storage

    E-Print Network [OSTI]

    Gallant, Betar M. (Betar Maurkah)

    2013-01-01

    New strategies and materials are needed to increase the energy and power capabilities of lithium storage devices for electric vehicle and grid-scale applications. Systems based on oxygen electrochemistry are promising due ...

  12. The influence of organic carbon on oxygen dynamics and bacterial sulfate reduction in inland shrimp ponds 

    E-Print Network [OSTI]

    Suplee, Michael Wayne

    1995-01-01

    Experiments conducted in saline aquaculture ponds demonstrated that organic matter was the primary factor influencing sediment sulfate reduction rates. Changes in sediment oxygen demand (SOD), sulfate reduction rates, and ...

  13. Behavior of alloy 617 at 650°C in low oxygen pressure environments

    E-Print Network [OSTI]

    Mas, Fanny (Fanny P.)

    2010-01-01

    The behavior of alloy 617 at 650°C in low oxygen partial pressure environments has been studied under static loading. Of particular interest was the crack growth rate in these conditions. For that, tests were conducted at ...

  14. New cofacial binuclear complexes for the oxygen reduction reaction and selective anion binding 

    E-Print Network [OSTI]

    Devoille, Aline M. J.

    2011-11-23

    This thesis describes the design, synthesis and reactivity of bimetallic complexes of doubly-pillared Schiff-base calixpyrrole ligands. Chapter One introduces the oxygen reduction reaction in light of the global ...

  15. Negative pressure effects in high-pressure oxygen-intercalated C{sub 60}

    SciTech Connect (OSTI)

    Schirber, J.E.; Assink, R.A.; Samara, G.A.; Morosin, B.; Loy, D. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    1995-06-01

    We have observed unexpected and as yet unexplained negative pressure effects in high-oxygen-pressure-treated C{sub 60} in which the orientational ordering temperature is greatly depressed. Such effects are not observed in identical studies with nitrogen.

  16. 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.

  17. Maintaining Low Oxygen (O2) in Coal Fueled Utility Boilers Using CO Instrumentation 

    E-Print Network [OSTI]

    Hopkins, D.; Downing, T.

    1986-01-01

    Following evaluation of various CO monitors and close attention to the boiler operating conditions, Southwestern Public Service Company has been successful in reducing the operating level of oxygen in Unit #1 at Tolk ...

  18. Physical properties and band structure of reactive molecular beam epitaxy grown oxygen engineered HfO{sub 2{+-}x}

    SciTech Connect (OSTI)

    Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany)

    2012-12-01

    We have conducted a detailed thin film growth structure of oxygen engineered monoclinic HfO{sub 2{+-}x} grown by reactive molecular beam epitaxy. The oxidation conditions induce a switching between (111) and (002) texture of hafnium oxide. The band gap of oxygen deficient hafnia decreases with increasing amount of oxygen vacancies by more than 1 eV. For high oxygen vacancy concentrations, defect bands form inside the band gap that induce optical transitions and p-type conductivity. The resistivity changes by several orders of magnitude as a function of oxidation conditions. Oxygen vacancies do not give rise to ferromagnetic behavior.

  19. 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

    Geologic CO2 sequestration (GCS) has been proposed as a viable strategy to reduce anthropogenic CO2 emission; however, the increased cost that will be incurred by fossil energy production facilities is a deterrent to implementation of this technology. Allowing impurities in the effluent CO2 stream could result in significant financial and energy savings for CO2 capture and separation. However, impurities such as O2 have the potential to influence the redox state and alter the geochemical interactions that occur within GCS reservoirs, which increases the concern for CO2 and brine leakage from the storage reservoir as well as the overlying groundwater contamination. In this work, to investigate the impact of O2 co-injected with CO2 on the geochemical interactions, especially the trace metal mobilization from a GCS reservoir rock, batch studies were conducted with Eau Claire siltstone collected from CO2 sequestration sites. The rock was reacted with synthetic brines in contact with either 100% CO2 or a mixture of 95 mole% CO2-5 mole% O2 at 10.1 MPa and 75 °C. Both microscopic and spectroscopic measurements, including 57Fe-Mössbauer spectroscopy, Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry, powder X-ray diffraction, scanning electron microscopy-energy dispersive x-ray spectroscopy, and chemical extraction were combined in this study to investigate reaction mechanisms. The Eau Claire siltstone contains quartz (52 wt%), fluorapatite (40%), and aluminosilicate (5%) as major components, and dolomite (2%), pyrite (1%), and small-particle-/poorly-crystalline Fe-oxides as minor components. With the introduction of CO2 into the reaction vessel containing rock and brine, the leaching of small amounts of fluorapatite, aluminosilicate, and dolomite occurred. Trace metals of environmental concern, including Pb, As, Cd, and Cu were detected in the leachate with concentrations up to 400 ppb in the CO2-brine-rock reaction system within 30 days. In the presence of O2, 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.

  20. 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.

  1. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shinesSolarNew scholarship supports returningNew MexicoReactors |NewNew Species of

  2. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shinesSolarNew scholarship supports returningNew MexicoReactors |NewNew Species

  3. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shinesSolarNew scholarship supports returningNew MexicoReactors |NewNew SpeciesNew

  4. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shinesSolarNew scholarship supports returningNew MexicoReactors |NewNewNew Species

  5. New Species of Cyanobacteria Forms Intracellular Carbonates

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework usesofPublications64 2.251 2.211New Species of Cyanobacteria Forms

  6. 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. %.

  7. Mass spectral characterization of oxygen-containing aromatics with methanol chemical ionization

    SciTech Connect (OSTI)

    Buchanan, M.V.

    1984-03-01

    Chemical ionization mass spectrometry with methanol and deuterated methanol as ionization reagents is used to differentiate oxygen-containing aromatics, including phenols, aromatic ethers, and aromatic substituted alcohols, as well as compounds containing more than one oxygen atom. The analogous sulfur-containing aromatics may be similarly differentiated. Methanol chemical ionization is used to characterize a neutral aromatic polar subfraction of a coal-derived liquid by combined gas chromatography/mass spectrometry. 16 references, 2 tables, 1 figure.

  8. An investigation of the relationship between blood flow and maximal oxygen intake 

    E-Print Network [OSTI]

    Riggs, Charles Elmer

    1973-01-01

    AN INVESTIGATION OF THE RELATIONSHIP BETWEEN BLOOD FLOW AND MAXIMAL OXYGEN INTAKE A Thesis by CHARLES ELMER RIGGS, JR. Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE May 1973 Major Subject: Health and Physical Education AN INVESTIGATION OF THE RELATIONSHIP BETWEEN BLOOD FLOW AND MAXIMAL OXYGEN INTAKE A Thesis by CHARLES ELMER RIGGS, JR. Approved as to style and content by: Chairman...

  9. Effect of bacterium Oceanospirillum on the corrosion potential and oxygen reduction of AISI 4340 steel 

    E-Print Network [OSTI]

    Popova, Snezana N.

    1992-01-01

    EFFECT OF BACTERIUM OCEANOSPIRILLUM ON THE CORROSION POTENTIAL AND OXYGEN REDUCI1ON OF AISI 4340 STEEL A Thesis by SNEZANA N. POPOVA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Chemical Engineering EFFECT OF BACTERIUM OCEANOSPIRILLUM ON THE CORROSION POTENTIAL AND OXYGEN REDUCTION OF AISI 4340 STEEL A Thesis by SNEZANA N. POPOVA Appmved as to style...

  10. 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.

  11. 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.

  12. 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.

  13. Electrocatalyst for oxygen reduction with reduced platinum oxidation and dissolution rates

    DOE Patents [OSTI]

    Adzic, Radoslav (East Setauket, NY); Zhang, Junliang (Stony Brook, NY); Vukmirovic, Miomir (Port Jefferson Station, NY)

    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.

  14. 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.

  15. 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.

  16. 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.

  17. Assessment Of Potential Indicator Species For Monitoring Environmental Contamination

    E-Print Network [OSTI]

    #12;Assessment Of Potential Indicator Species For Monitoring Environmental Contamination contamination in the aquatic component of the Fraser River Basin, British Columbia. A list of criterion were species for laboratory study; and 5) knowledge availability pertaining to contaminant research

  18. DESIGNATION OF FOCAL VERTEBRATE SPECIES FOR THE LAKE TAHOE BASIN

    E-Print Network [OSTI]

    extirpated species were candidates for focal species status: Mountain sheep, heather vole, canyon mouse, white-tailed hare, wolverine, Sierra Nevada red fox, and grizzly bear. Amphibians and Reptiles We

  19. PRIMARY RESEARCH PAPER A novel, combined approach to assessing species

    E-Print Network [OSTI]

    Morphological species of freshwater microalgae often have broad geographic distribution. However, traditional distribu- tional stability among microalgal species groups such as the desmids. Keywords Microalgae microalgae have recently been undergoing major conceptual changes in the light of increasing evidence

  20. Mycosphaerella species causing leaf disease in South African Eucalyptus plantations

    E-Print Network [OSTI]

    Mycosphaerella species causing leaf disease in South African Eucalyptus plantations Gavin C. HUNTER Eucalyptus plantations provide an important source of hardwood for forestry industries, worldwide. Several species of Mycosphaerella are associated with a destructive Eucalyptus leaf disease known