National Library of Energy BETA

Sample records for naturally occurring isotopes

  1. Naturally occurring radionuclides in agricultural products: An overview

    SciTech Connect (OSTI)

    Hanlon, E.A.

    1994-07-01

    Low levels of naturally occurring radionuclides exist in phosphatic clays, a by-product of phosphatic mining and beneficiation processes. Concerns about these radionuclides entering the human food chain were an immediate research priority before the phosphate clays could be reclaimed for intensive agricultural purposes. Efforts included the assembly of a large body of data from both sons and plants, part of which were produced by the Polk County (Florida) Mined Lands Agricultural Research/Demonstration Project MLAR/DP. Additional detailed studies involving dairy and beef cattle (Bos taurus) were conducted by researchers working with the MLAR/DP. A national symposium was conducted in which data concerning the MLAR/DP work and other research projects also dealing with naturally occurring radionuclides in agriculture could be discussed. The symposium included invited review papers dealing with the identification of radionuclide geological origins, the geochemistry and movement of radionuclides within the environment, mechanisms of plant uptake, entry points into the food chain, and evaluation of dose and risk assessment to the consumer of low levels of radionuclides. The risk to human health of an individual obtaining 0.1 of his or her dietary intake from crops produced on phosphatic clays increased by 1 in 5 x 10{sup 6}/yr above a control individual consuming no food grown on phosphatic clays. Leaf tissues were found to be generally higher than fruit, grain, or root tissues. The natural range in radionuclide content among various food types was greater than the difference in radionuclides content between the same food produced on phosphatic clays vs. natural soils. 19 refs.

  2. Manufactured Home Testing in Simulated and Naturally Occurring High Winds

    SciTech Connect (OSTI)

    W. D. Richins; T. K. Larson

    2006-08-01

    A typical double-wide manufactured home was tested in simulated and naturally occurring high winds to understand structural behavior and improve performance during severe windstorms. Seven (7) lateral load tests were conducted on a double-wide manufactured home at a remote field test site in Wyoming. An extensive instrumentation package monitored the overall behavior of the home and collected data vital to validating computational software for the manufactured housing industry. The tests were designed to approach the design load of the home without causing structural damage, thus allowing the behavior of the home to be accessed when the home was later exposed to high winds (to 80-mph). The data generally show near-linear initial system response with significant non-linear behavior as the applied loads increase. Load transfer across the marriage line is primarily compression. Racking, while present, is very small. Interface slip and shear displacement along the marriage line are nearly insignificant. Horizontal global displacements reached 0.6 inch. These tests were designed primarily to collect data necessary to calibrate a desktop analysis and design software tool, MHTool, under development at the Idaho National Laboratory specifically for manufactured housing. Currently available analysis tools are, for the most part, based on methods developed for “stick built” structures and are inappropriate for manufactured homes. The special materials utilized in manufactured homes, such as rigid adhesives used in the connection of the sheathing materials to the studs, significantly alter the behavior of manufactured homes under lateral loads. Previous full scale tests of laterally loaded manufactured homes confirm the contention that conventional analysis methods are not applicable. System behavior dominates the structural action of manufactured homes and its prediction requires a three dimensional analysis of the complete unit, including tiedowns. This project was sponsored by the US Department of Energy, US Department of Housing and Urban Development, and the Manufactured Housing Institute. The results of this research can lead to savings in annual losses of life and property by providing validated information to enable the advancement of code requirements and by developing engineering software that can predict and optimize wind resistance.

  3. A century of oil and gas exploration in Albania: assessment of Naturally Occurring Radioactive Materials (NORMs)

    E-Print Network [OSTI]

    Xhixha, Gerti; Callegari, Ivan; Colonna, Tommaso; Hasani, Fadil; Mantovani, Fabio; Shala, Ferat; Strati, Virginia; Kaçeli, Merita Xhixha

    2015-01-01

    Because potential Naturally Occurring Radioactive Materials (NORMs) generated from oil and gas extractions in Albania have been disposed without regulatory criteria in many decades, an extensive survey in one of the most productive regions (Vlora-Elbasan) has been performed. Among 52 gamma-ray spectrometry measurements of soil, oil-sand, sludge, produced water and crude oil samples, we discover that relatively low activity concentrations of 226Ra, 228Ra, 228Th and 40K, which are 23 +/- 2 Bq/kg, 23 +/- 2 Bq/kg, 24 +/- 3 Bq/kg and 549 +/- 12 Bq/kg, respectively, come from oil-sand produced by hydrocarbon extraction from molasses formations. The mineralogical characterization together with the 228Ra/40K and 226Ra/40K ratios of these Neogene deposits confirm the geological and geodynamic model that predicts a dismantling of Mesozoic source rocks. The average activity concentrations (+/- standard deviations) of the radium isotopes (226Ra, 228Ra) and of the 228Th and 40K radionuclides in soil samples are determined...

  4. USE OF NATURALLY-OCCURRING TRACERS TO MONITOR TWO-PHASE CONDITIONS...

    Open Energy Info (EERE)

    USE OF NATURALLY-OCCURRING TRACERS TO MONITOR TWO-PHASE CONDITIONS IN THE COSO EGS PROJECT Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  5. Chapter 5. Conclusion Uranium, a naturally occurring element, contributes to low levels of natural background radiation in the

    E-Print Network [OSTI]

    5-1 Chapter 5. Conclusion Uranium, a naturally occurring element, contributes to low levels into uranium oxide or other chemical forms usable in industry. Uranium undergoes radioactive decay into a long are extracted from the earth. Protore is mined uranium ore that is not rich enough to meet the market demand

  6. Isotopes

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

    Nuclear Physics Isotopes Isotopes Isotopes produced at Los Alamos National Laboratory are saving lives, advancing cutting-edge research and keeping the U.S. safe. Get Expertise...

  7. Systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies

    DOE Patents [OSTI]

    Fliermans; , Carl B. (Augusta, GA)

    2012-08-07

    Some or all of the needs above can be addressed by embodiments of the invention. According to embodiments of the invention, systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies can be implemented. In one embodiment, a method for storing hydrogen can be provided. The method can include providing diatoms comprising diatomaceous earth or diatoms from a predefined culture. In addition, the method can include heating the diatoms in a sealed environment in the presence of at least one of titanium, a transition metal, or a noble metal to provide a porous hydrogen storage medium. Furthermore, the method can include exposing the porous hydrogen storage medium to hydrogen. In addition, the method can include storing at least a portion of the hydrogen in the porous hydrogen storage medium.

  8. Lead isotopes in sediments of the Loire River (France): natural versus anthropogenic origin

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Lead isotopes in sediments of the Loire River (France): natural versus anthropogenic origin France) were investigated by means of lead isotopes determined on the labile sediment fraction, or acid-extractable matter (AEM). The combination of trace elements and lead isotopes allows deciphering the origin

  9. An overview of naturally occurring radioactive materials (NORM) in the petroleum industry

    SciTech Connect (OSTI)

    Smith, K.P.

    1992-12-01

    Oil and gas extraction and processing operations sometimes accumulate naturally occurring radioactive materials (NORM) at concentrations above normal in by-product waste streams. Results from NORM surveys indicate that radionuclide concentrations can be quite variable, ranging from undetectable to extremely high levels. To date, efforts to characterize the geographic distribution of NORM have been limited by poor statistical representation. In addition, the fate of NORM in the environment has not been fully defined, and few human health risk assessment have been conducted. Both the petroleum industry and regulators are becoming increasingly concerned about the presence of NORM. At present, most existing federal environmental regulations do not address oil and gas NORM, and only a few states have developed regulatory programs. Available data suggest that the occurrence of NORM (and associated health risks) is significant enough to warrant increased regulatory control. However, before these regulations can be developed, additional research is needed to (1) better characterize the occurrence and distribution of NORM throughout the industry, (2) quantify hazards posed by NORM to industry workers and the general public, and (3) develop effective waste treatment and minimization technologies that will lower the risk associated with NORM and reduce disposal costs.

  10. Manufactured Home Testing in Simulated and Naturally Occurring High Winds for WCTE Conference

    SciTech Connect (OSTI)

    William D. Richins; Thomas K. Larson; Jeffrey M. Lacy; Ryan G. Kobbe

    2006-08-01

    A typical double-wide manufactured home was tested in simulated and naturally occurring high winds to understand structural behavior and improve performance during severe windstorms. Seven (7) lateral load tests were conducted on a double-wide manufactured home at a remote field test site in Wyoming. An extensive instrumentation package monitored the overall behavior of the home and collected data vital to validating computational software for the manufactured housing industry. The tests were designed to approach the design load of the home without causing structural damage, thus allowing the behavior of the home to be accessed when the home was later exposed to high winds (to 80-mph). The data generally show near-linear initial system response with significant non-linear behavior as the applied loads increase. Load transfer across the marriage line is primarily compression. Racking, while present, is very small. Interface slip and shear displacement along the marriage line are nearly insignificant. Horizontal global displacements reached 0.6 inch. These tests were designed primarily to collect data necessary to calibrate a desktop analysis and design software tool, MHTool, under development at the Idaho National Laboratory specifically for manufactured housing. Currently available analysis tools are, for the most part, based on methods developed for "stick built" structures and are inappropriate for manufactured homes. The special materials utilized in manufactured homes, such as rigid adhesives used in the connection of the sheathing materials to the studs, significantly alter the behavior of manufactured homes under lateral loads. Previous full scale tests of laterally loaded manufactured homes confirm the contention that conventional analysis methods are not applicable. System behavior dominates the structural action of manufactured homes and its prediction requires a three dimensional analysis of the complete unit, including tie-downs. This project was sponsored by the US Department of Energy, US Department of Housing and Urban Development, and the Manufactured Housing Institute. The results of this research can lead to savings in annual losses of life and property by providing validated information to enable the advancement of code requirements and by developing engineering software that can predict and optimize wind resistance.

  11. Investigation of Naturally Occurring Radio Nuclides in Shir-kuh Granites

    SciTech Connect (OSTI)

    Mazarei, Mohammad Mehdi; Zarei, Mojtaba

    2011-12-26

    One of the principle natural radiation resources is Granite which can be dangerous for human because of its radiations. Based on this fact, in this research we attempt to specify the activity amount of these natural radio nuclides, existing in Shir-kuh Granite of Yazd state. To specify the activity amount of this natural radio nuclides, it has been applied the measurement method of Gamma spectroscopy using high purity Germanium (HPGe) detector.

  12. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo

    E-Print Network [OSTI]

    Roma "La Sapienza", Università di

    Available online 16 September 2014 Keywords: Lignite Coal fired power plant Fly ash Bottom ash Naturally depends primarily on lignite-fired power plants. During coal com- bustion, huge amounts of fly ash exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated

  13. Lab 2: Mineral Lab notes. Minerals are inorganic, solid, naturally occurring substances that have a characteristic chemical compositions,

    E-Print Network [OSTI]

    Li, X. Rong

    Lab 2: Mineral Lab notes. Minerals are inorganic, solid, naturally occurring substances that have composition is the chemical elements that make up any given mineral. For instance, the mineral quartz is silicon dioxide SiO2; the mineral galena is an ore of lead, and its chemical formula is PbS, a lead

  14. Naturally occurring, optically driven, cellular rotor J. A. Dharmadhikari, S. Roy, A. K. Dharmadhikari, S. Sharma, and D. Mathura)

    E-Print Network [OSTI]

    Sharma, Shobhona

    005, India (Received 10 June 2004; accepted 20 October 2004) We report the conversion of optical energy into mechanical energy by naturally occurring red blood cells (RBCs) placed in an optical trap material, biconcave disk-shaped red blood cells (RBCs), which convert optical energy into mechanical energy

  15. Sulphoraphane, a naturally occurring isothiocyanate induces apoptosis in breast cancer cells by targeting heat shock proteins

    SciTech Connect (OSTI)

    Sarkar, Ruma; Mukherjee, Sutapa [Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India)] [Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India); Biswas, Jaydip [Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India)] [Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India); Roy, Madhumita, E-mail: mitacnci@yahoo.co.in [Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India)] [Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37, SP Mukherjee Road, Kolkata 700 026 (India)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer HSPs (27, 70 and 90) and HSF1 are overexpressed in MCF-7 and MDA-MB-231 cells. Black-Right-Pointing-Pointer Sulphoraphane, a natural isothiocyanate inhibited HSPs and HSF1 expressions. Black-Right-Pointing-Pointer Inhibition of HSPs and HSF1 lead to regulation of apoptotic proteins. Black-Right-Pointing-Pointer Alteration of apoptotic proteins activate of caspases particularly caspase 3 and 9 leading to induction of apoptosis. Black-Right-Pointing-Pointer Alteration of apoptotic proteins induce caspases leading to induction of apoptosis. -- Abstract: Heat shock proteins (HSPs) are involved in protein folding, aggregation, transport and/or stabilization by acting as a molecular chaperone, leading to inhibition of apoptosis by both caspase dependent and/or independent pathways. HSPs are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation, differentiation, invasion and metastasis. HSPs particularly 27, 70, 90 and the transcription factor heat shock factor1 (HSF1) play key roles in the etiology of breast cancer and can be considered as potential therapeutic target. The present study was designed to investigate the role of sulphoraphane, a natural isothiocyanate on HSPs (27, 70, 90) and HSF1 in two different breast cancer cell lines MCF-7 and MDA-MB-231 cells expressing wild type and mutated p53 respectively, vis-a-vis in normal breast epithelial cell line MCF-12F. It was furthermore investigated whether modulation of HSPs and HSF1 could induce apoptosis in these cells by altering the expressions of p53, p21 and some apoptotic proteins like Bcl-2, Bax, Bid, Bad, Apaf-1 and AIF. Sulphoraphane was found to down-regulate the expressions of HSP70, 90 and HSF1, though the effect on HSP27 was not pronounced. Consequences of HSP inhibition was upregulation of p21 irrespective of p53 status. Bax, Bad, Apaf-1, AIF were upregulated followed by down-regulation of Bcl-2 and this effect was prominent in MCF-7 than in MDA-MB-231. However, very little change in the expression of Bid was observed. Alteration in Bcl-2 Bax ratio resulted in the release of cytochrome c from mitochondria and activation of caspases 3 and 9 which are in agreement with apoptotic index values. Sulphoraphane therefore can be regarded as a potent inducer of apoptosis due to HSP modulation in breast cancer cells.

  16. Using naturally occurring radionuclides to determine drinking water age in a community water system

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

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (?est: ± 3.8 h, P 2 = 0.998, n =more »11) and 25 days old (?est: ± 13.3 h, P 2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

  17. Prediction of rodent carcinogenic potential of naturally occurring chemicals in the human diet using high-throughput QSAR predictive modeling

    SciTech Connect (OSTI)

    Valerio, Luis G. . E-mail: luis.valerio@FDA.HHS.gov; Arvidson, Kirk B.; Chanderbhan, Ronald F.; Contrera, Joseph F.

    2007-07-01

    Consistent with the U.S. Food and Drug Administration (FDA) Critical Path Initiative, predictive toxicology software programs employing quantitative structure-activity relationship (QSAR) models are currently under evaluation for regulatory risk assessment and scientific decision support for highly sensitive endpoints such as carcinogenicity, mutagenicity and reproductive toxicity. At the FDA's Center for Food Safety and Applied Nutrition's Office of Food Additive Safety and the Center for Drug Evaluation and Research's Informatics and Computational Safety Analysis Staff (ICSAS), the use of computational SAR tools for both qualitative and quantitative risk assessment applications are being developed and evaluated. One tool of current interest is MDL-QSAR predictive discriminant analysis modeling of rodent carcinogenicity, which has been previously evaluated for pharmaceutical applications by the FDA ICSAS. The study described in this paper aims to evaluate the utility of this software to estimate the carcinogenic potential of small, organic, naturally occurring chemicals found in the human diet. In addition, a group of 19 known synthetic dietary constituents that were positive in rodent carcinogenicity studies served as a control group. In the test group of naturally occurring chemicals, 101 were found to be suitable for predictive modeling using this software's discriminant analysis modeling approach. Predictions performed on these compounds were compared to published experimental evidence of each compound's carcinogenic potential. Experimental evidence included relevant toxicological studies such as rodent cancer bioassays, rodent anti-carcinogenicity studies, genotoxic studies, and the presence of chemical structural alerts. Statistical indices of predictive performance were calculated to assess the utility of the predictive modeling method. Results revealed good predictive performance using this software's rodent carcinogenicity module of over 1200 chemicals, comprised primarily of pharmaceutical, industrial and some natural products developed under an FDA-MDL cooperative research and development agreement (CRADA). The predictive performance for this group of dietary natural products and the control group was 97% sensitivity and 80% concordance. Specificity was marginal at 53%. This study finds that the in silico QSAR analysis employing this software's rodent carcinogenicity database is capable of identifying the rodent carcinogenic potential of naturally occurring organic molecules found in the human diet with a high degree of sensitivity. It is the first study to demonstrate successful QSAR predictive modeling of naturally occurring carcinogens found in the human diet using an external validation test. Further test validation of this software and expansion of the training data set for dietary chemicals will help to support the future use of such QSAR methods for screening and prioritizing the risk of dietary chemicals when actual animal data are inadequate, equivocal, or absent.

  18. Geochemical and Strontium Isotope Characterization of Produced Waters from Marcellus Shale Natural Gas Extraction

    SciTech Connect (OSTI)

    Elizabeth C. Chapman,† Rosemary C. Capo,† Brian W. Stewart,*,† Carl S. Kirby,‡ Richard W. Hammack,§

    2012-02-24

    Extraction of natural gas by hydraulic fracturing of the Middle Devonian Marcellus Shale, a major gas-bearing unit in the Appalachian Basin, results in significant quantities of produced water containing high total dissolved solids (TDS). We carried out a strontium (Sr) isotope investigation to determine the utility of Sr isotopes in identifying and quantifying the interaction of Marcellus Formation produced waters with other waters in the Appalachian Basin in the event of an accidental release, and to provide information about the source of the dissolved solids. Strontium isotopic ratios of Marcellus produced waters collected over a geographic range of ?375 km from southwestern to northeastern Pennsylvania define a relatively narrow set of values (?Sr SW = +13.8 to +41.6, where ?Sr SW is the deviation of the 87Sr/86Sr ratio from that of seawater in parts per 104); this isotopic range falls above that of Middle Devonian seawater, and is distinct from most western Pennsylvania acid mine drainage and Upper Devonian Venango Group oil and gas brines. The uniformity of the isotope ratios suggests a basin-wide source of dissolved solids with a component that is more radiogenic than seawater. Mixing models indicate that Sr isotope ratios can be used to sensitively differentiate between Marcellus Formation produced water and other potential sources of TDS into ground or surface waters.

  19. Radiological Impact Associated to Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) from Coal-Fired Power Plants Emissions - 13436

    SciTech Connect (OSTI)

    Dinis, Maria de Lurdes; Fiuza, Antonio; Soeiro de Carvalho, Jose; Gois, Joaquim [Geo-Environment and Resources Research Centre (CIGAR), Porto University, Faculty of Engineering - FEUP, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal)] [Geo-Environment and Resources Research Centre (CIGAR), Porto University, Faculty of Engineering - FEUP, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Meira Castro, Ana Cristina [School of Engineering Polytechnic of Porto - ISEP, Rua Dr. Antonio Bernardino de Almeida, 431, 4200-072, Porto (Portugal)] [School of Engineering Polytechnic of Porto - ISEP, Rua Dr. Antonio Bernardino de Almeida, 431, 4200-072, Porto (Portugal)

    2013-07-01

    Certain materials used and produced in a wide range of non-nuclear industries contain enhanced activity concentrations of natural radionuclides. In particular, electricity production from coal is one of the major sources of increased human exposure to naturally occurring radioactive materials. A methodology was developed to assess the radiological impact due to natural radiation background. The developed research was applied to a specific case study, the Sines coal-fired power plant, located in the southwest coastline of Portugal. Gamma radiation measurements were carried out with two different instruments: a sodium iodide scintillation detector counter (SPP2 NF, Saphymo) and a gamma ray spectrometer with energy discrimination (Falcon 5000, Canberra). Two circular survey areas were defined within 20 km of the power plant. Forty relevant measurements points were established within the sampling area: 15 urban and 25 suburban locations. Additionally, ten more measurements points were defined, mostly at the 20-km area. The registered gamma radiation varies from 20 to 98.33 counts per seconds (c.p.s.) corresponding to an external gamma exposure rate variable between 87.70 and 431.19 nGy/h. The highest values were measured at locations near the power plant and those located in an area within the 6 and 20 km from the stacks. In situ gamma radiation measurements with energy discrimination identified natural emitting nuclides as well as their decay products (Pb-212, Pb-2142, Ra-226, Th-232, Ac-228, Th-234, Pa-234, U- 235, etc.). According to the results, an influence from the stacks emissions has been identified both qualitatively and quantitatively. The developed methodology accomplished the lack of data in what concerns to radiation rate in the vicinity of Sines coal-fired power plant and consequently the resulting exposure to the nearby population. (authors)

  20. Thermoluminescence (TL) Analysis and Fading Studies of Naturally Occurring Salt Irradiated by 500 mGy Gamma Rays

    SciTech Connect (OSTI)

    Tiwari, Ramesh Chandra; Pau, Kham Suan [Department of Physics, Mizoram University: Tanhril Campus, Aizawl-796004, Mizoram (India)

    2011-10-20

    The aim of the present study was to investigate the potential of the naturally occurring salt for the dosimetry purposes, using TL. The fine powder samples (20 mg) were irradiated by {gamma}- rays from 500 mGy to 2500 mGy by using Theratron-780C Cobalt-60 source, however, this paper discusses about 500 mGy only. The TL glow curve peak parameters were studied by using Chen's peak shape equation. TL glow curves were compared with fitted curves using glow curve deconvolution (GCD) method by using Kitis expression. The kinetic parameter values (E, b and s) so calculated, are in good agreement with those available in literature. The calculated energy values were also verified by using various heating rate (VHR) method. {chi}{sup 2} test and figure of merit (FOM) calculation was done to accept the goodness of fit between the curves. Fading studies of the sample showed a good fitting between the curves. The analysis suggests that natural salt should be considered for dosimetry purposes.

  1. Electron spin coherence of shallow donors in natural and isotopically enriched germanium

    E-Print Network [OSTI]

    A. J. Sigillito; R. M. Jock; A. M. Tyryshkin; J. W. Beeman; E. E. Haller; K. M. Itoh; S. A. Lyon

    2015-11-07

    Germanium is a widely used material for electronic and optoelectronic devices and recently it has become an important material for spintronics and quantum computing applications. Donor spins in silicon have been shown to support very long coherence times ($T_{2}$) when the host material is isotopically enriched to remove any magnetic nuclei. Germanium also has non-magnetic isotopes so it is expected to support long $T_{2}$s while offering some new properties. Compared to Si, Ge has a strong spin-orbit coupling, large electron wavefunction, high mobility, and highly anisotropic conduction band valleys which will all give rise to new physics. In this Letter, the first pulsed electron spin resonance (ESR) measurements of $T_{2}$ and the spin-lattice relaxation ($T_1$) times for $^{75}$As and $^{31}$P donors in natural and isotopically enriched germanium are presented. We compare samples with various levels of isotopic enrichment and find that spectral diffusion due to $^{73}$Ge nuclear spins limits the coherence in samples with significant amounts of $^{73}$Ge. For the most highly enriched samples, we find that $T_1$ limits $T_2$ to $T_2 = 2T_1$. We report an anisotropy in $T_1$ and the ensemble linewidths for magnetic fields oriented along different crystal axes but do not resolve any angular dependence to the spectral-diffusion-limited $T_2$ in samples with $^{73}$Ge.

  2. Electron spin coherence of shallow donors in natural and isotopically enriched germanium

    E-Print Network [OSTI]

    A. J. Sigillito; R. M. Jock; A. M. Tyryshkin; J. W. Beeman; E. E. Haller; K. M. Itoh; S. A. Lyon

    2015-09-16

    Germanium is a widely used material for electronic and optoelectronic devices and recently it has become an important material for spintronics and quantum computing applications. Donor spins in silicon have been shown to support very long coherence times ($T_{2}$) when the host material is isotopically enriched to remove any magnetic nuclei. Germanium also has non-magnetic isotopes so it is expected to support long $T_{2}$s while offering some new properties. Compared to Si, Ge has a strong spin-orbit coupling, large electron wavefunction, high mobility, and highly anisotropic conduction band valleys which will all give rise to new physics. In this Letter, the first pulsed electron spin resonance (ESR) measurements of $T_{2}$ and the spin-lattice relaxation ($T_1$) times for $^{75}$As and $^{31}$P donors in natural and isotopically enriched germanium are presented. We compare samples with various levels of isotopic enrichment and find that spectral diffusion due to $^{73}$Ge nuclear spins limits the coherence in samples with significant amounts of $^{73}$Ge. For the most highly enriched samples, we find that $T_1$ limits $T_2$ to $T_2 = 2T_1$. We report an anisotropy in $T_1$ and the ensemble linewidths for magnetic fields oriented along different crystal axes but do not resolve any angular dependence to the spectral-diffusion-limited $T_2$ in samples with $^{73}$Ge.

  3. Integrated Approach to Use Natural Chemical and Isotopic Tracers to Estimate Fracture Spacing and Surface Area in EGS Systems

    Broader source: Energy.gov [DOE]

    DOE Geothermal Peer Review 2010 - Presentation. This objective of this project is to develop an innovative approach to estimate fracture surface area and spacing through interpretation of signals of natural chemical and isotopic tracers.

  4. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Frank R. Rack

    2006-09-20

    Cooperative Agreement DE-FC26-01NT41329 between Joint Oceanographic Institutions and DOE-NETL was divided into two phases based on successive proposals and negotiated statements of work pertaining to activities to sample and characterize methane hydrates on ODP Leg 204 (Phase 1) and on IODP Expedition 311 (Phase 2). The Phase 1 Final Report was submitted to DOE-NETL in April 2004. This report is the Phase 2 Final Report to DOE-NETL. The primary objectives of Phase 2 were to sample and characterize methane hydrates using the systems and capabilities of the D/V JOIDES Resolution during IODP Expedition 311, to enable scientists the opportunity to establish the mass and distribution of naturally occurring gas and gas hydrate at all relevant spatial and temporal scales, and to contribute to the DOE methane hydrate research and development effort. The goal of the work was to provide expanded measurement capabilities on the JOIDES Resolution for a dedicated hydrate cruise to the Cascadia continental margin off Vancouver Island, British Columbia, Canada (IODP Expedition 311) so that hydrate deposits in this region would be well characterized and technology development continued for hydrate research. IODP Expedition 311 shipboard activities on the JOIDES Resolution began on August 28 and were concluded on October 28, 2005. The statement of work for this project included three primary tasks: (1) research management oversight, provided by JOI; (2) mobilization, deployment and demobilization of pressure coring and core logging systems, through a subcontract with Geotek Ltd.; and, (3) mobilization, deployment and demobilization of a refrigerated container van that will be used for degassing of the Pressure Core Sampler and density logging of these pressure cores, through a subcontract with the Texas A&M Research Foundation (TAMRF). Additional small tasks that arose during the course of the research were included under these three primary tasks in consultation with the DOE-NETL Program Manager. All tasks outlined in the original statement of work were accomplished except for the deployment and use of the X-ray CT system under Subtask 2-2. This reduction in scope provided resources that were applied to other activities to support the overall project. Post-expedition analysis of results and report writing will continue beyond this reporting period, however, all field deployments associated with this project have been successfully concluded as of this writing.

  5. IN-SITU SAMPLING AND CHARACTERIZATION OF NATURALLY OCCURRING MARINE METHANE HYDRATE USING THE D/V JOIDES RESOLUTION

    SciTech Connect (OSTI)

    Rack, Frank R.; Dickens, Gerald; Ford, Kathryn; Schroeder, Derryl; Storms, Michael

    2002-08-01

    The primary accomplishment of the JOI Cooperative Agreement with DOE/NETL in this quarter was the preparation of tools and measurement systems for deployment, testing and use on ODP Leg 204, which will study hydrate deposits on Hydrate Ridge, offshore Oregon. Additional accomplishments were related to the postcruise evaluation of tools and measurements systems used on ODP Leg 201 along the Peru margin from January through March, 2002. The operational results from the use of the Pressure Core Sampler (PCS) tool and the PCS Gas Manifold on ODP Leg 201 are evaluated in this progress report in order to prepare for the upcoming deployments on ODP Leg 204 in July, 2002. The PCS was deployed 17 times during ODP Leg 201 and successfully retrieved cores from a broad range of lithologies and sediment depths along the Peru margin. Eleven deployments were entirely successful, collecting between 0.5 and 1.0 meters of sediment at greater than 75% of hydrostatic pressure. The PCS gas manifold was used in conjunction with the Pressure Core Sampler (PCS) throughout ODP Leg 201 to measure the total volume and composition of gases recovered in sediment cores associated with methane gas hydrates. The FUGRO Pressure Corer (FPC), one of the HYACE/HYACINTH pressure coring tools, was also deployed on the D/V JOIDES Resolution during ODP Legs 201 to field-test this coring system at three shallow-water sites located offshore Peru. The field-testing of these tools provides a corollary benefit to DOE/NETL at no cost to this project. The testing of these tools on the D/V JOIDES Resolution was negotiated as part of a cooperative agreement between JOI/ODP and the HYACINTH partners. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were used extensively during ODP Leg 201. The data obtained from the successful deployments of these tools is still being evaluated by the scientists and engineers involved in this testing; however, preliminary results are presented in this report. An infrared-thermal imaging system (IR-TIS) was deployed for the first time on ODP Leg 201. This system was used to identify methane hydrate intervals in the recovered cores. Initial discussions of these experiments are provided in this report. This report is an overview of the field measurements made on recovered sediment cores and the downhole measurements made during ODP Leg 201. These results are currently being used to incorporate the ''lessons learned'' from these deployments to prepare for a dedicated ODP leg to study the characteristics of naturally-occurring hydrates in the subsurface environment of Hydrate Ridge, offshore Oregon during ODP Leg 204, which will take place from July through September, 2002.

  6. Blimp-1{delta}exon7: A naturally occurring Blimp-1 deletion mutant with auto-regulatory potential

    SciTech Connect (OSTI)

    Schmidt, Doris; Nayak, Arnab; Schumann, Julia E.; Schimpl, Anneliese; Berberich, Ingolf Berberich-Siebelt, Friederike

    2008-12-10

    Blimp-1 is a master regulator of terminal B cell differentiation and plays a pivotal role in various developmental processes. In addition to full length Blimp-1, a Blimp-1 mRNA lacking exon 7 (Blimp-1{delta}7) has been described to occur in murine B cells. The activity and function of the mutant mRNA-encoded protein (Blimp-1{delta}7), lacking three crucial zinc fingers necessary for DNA interaction, is completely unknown. Since isoforms of other prdm family proteins affect each other's functions, we wondered whether Blimp-1{delta}7 still plays a role in B cells, independent of direct DNA binding. In this study, we found that Blimp-1{delta}7 is preferentially expressed in naive CD19{sup +} B cells. A fraction of Blimp-1{delta}7 migrates to the nucleus, colocalizes with HDAC2 and is found at sites of repressed chromatin, although it does not bind to the Blimp-1 DNA consensus site. Unexpectedly, Blimp-1 and Blimp-1{delta}7 homodimerize as well as heterodimerize with each other. Ectopic expression of Blimp-1{delta}7 in WEHI 231 cells, a Blimp-1-negative murine lymphoma line, leads to cessation of proliferation and enhancement of apoptosis. Importantly, LPS-induced differentiation is suppressed in the presence of Blimp-1{delta}7. This is in agreement with our finding that Blimp-1{delta}7 interferes with endogenous Blimp-1 expression. Thus, our data suggest an auto-regulatory mechanism of Blimp-1 activation.

  7. No-go Theorem for One-way Quantum Computing on Naturally Occurring Two-level Systems

    E-Print Network [OSTI]

    Jianxin Chen; Xie Chen; Runyao Duan; Zhengfeng Ji; Bei Zeng

    2010-04-21

    One-way quantum computing achieves the full power of quantum computation by performing single particle measurements on some many-body entangled state, known as the resource state. As single particle measurements are relatively easy to implement, the preparation of the resource state becomes a crucial task. An appealing approach is simply to cool a strongly correlated quantum many-body system to its ground state. In addition to requiring the ground state of the system to be universal for one-way quantum computing, we also want the Hamiltonian to have non-degenerate ground state protected by a fixed energy gap, to involve only two-body interactions, and to be frustration-free so that measurements in the course of the computation leave the remaining particles in the ground space. Recently, significant efforts have been made to the search of resource states that appear naturally as ground states in spin lattice systems. The approach is proved to be successful in spin-5/2 and spin-3/2 systems. Yet, it remains an open question whether there could be such a natural resource state in a spin-1/2, i.e., qubit system. Here, we give a negative answer to this question by proving that it is impossible for a genuinely entangled qubit states to be a non-degenerate ground state of any two-body frustration-free Hamiltonian. What is more, we prove that every spin-1/2 frustration-free Hamiltonian with two-body interaction always has a ground state that is a product of single- or two-qubit states, a stronger result that is interesting independent of the context of one-way quantum computing.

  8. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank; Bohrmann, Gerhard; Trehu, Anne; Storms, Michael; Schroeder, Derryl

    2002-09-30

    The primary accomplishment of the JOI Cooperative Agreement with DOE/NETL in this quarter was the deployment of tools and measurement systems on ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September, 2002. During Leg 204, we cored and logged 9 sites on the Oregon continental margin to determine the distribution and concentration of gas hydrates in an accretionary ridge and adjacent slope basin, investigate the mechanisms that transport methane and other gases into the gas hydrate stability zone (GHSZ), and obtain constraints on physical properties of hydrates in situ. A 3D seismic survey conducted in 2000 provided images of potential subsurface fluid conduits and indicated the position of the GHSZ throughout the survey region. After coring the first site, we acquired Logging-While-Drilling (LWD) data at all but one site to provide an overview of downhole physical properties. The LWD data confirmed the general position of key seismic stratigraphic horizons and yielded an initial estimate of hydrate concentration through the proxy of in situ electrical resistivity. These records proved to be of great value in planning subsequent coring. The second new hydrate proxy to be tested was infrared thermal imaging of cores on the catwalk as rapidly as possible after retrieval. The thermal images were used to identify hydrate samples and to map estimate the distribution and texture of hydrate within the cores. Geochemical analyses of interstitial waters and of headspace and void gases provide additional information on the distribution and concentration of hydrate within the stability zone, the origin and pathway of fluids into and through the GHSZ, and the rates at which the process of gas hydrate formation is occurring. Bio- and lithostratigraphic description of cores, measurement of physical properties, and in situ pressure core sampling and thermal measurements complement the data set, providing ground-truth tests of inferred physical and sedimentological properties. Among the most interesting preliminary results are: (1) the discovery that gas hydrates are distributed through a broad depth range within the GHSZ and that different physical and chemical proxies for hydrate distribution and concentration give generally consistent results; (2) evidence for the importance of sediment properties for controlling the migration of fluids in the accretionary complex; (3) geochemical indications that the gas hydrate system at Hydrate Ridge contains significant concentrations of higher order hydrocarbons and that fractionation and mixing signals will provide important constraints on gas hydrate dynamics; and (4) the discovery of very high chlorinity values that extend for at least 10 mbsf near the summit, indicating that hydrate formation here must be very rapid.

  9. Isotopic studies of rare gases in terrestrial samples and natural nucleosynthesis

    SciTech Connect (OSTI)

    Not Available

    1990-07-01

    This project is concerned with research in rare gas mass spectrometry. We read the natural record that isotopes of the rare gases provide. We study fluids using a system (RARGA) that is sometimes deployed in the field. In 1990 there was a strong effort to reduce the backlog of RARGA samples on hand, so that it was a year of intensive data gathering. Samples from five different areas in the western United States and samples from Guatemala and Australia were analyzed. In a collaborative study we also began analyzing noble gases from rocks associated with the fluids. An important objective, continuing in 1991, is to understand better the reasons for somewhat elevated {sup 3}He/{sup 4}He ratios in regions where there is no contemporary volcanism which could produce the effect by addition of mantle helium. Our helium data have given us and our collaborators some insights, which are to be followed up, into gold mineralization in geothermal regions. Our DOE work in calibrating a sensitive laser microprobe mass spectrometer for noble gases in fluid inclusions continues. Having completed a series of papers on noble gases in diamonds, we next will attempt to make precise isotopic measurements on xenon from mantle sources, in search of evidence for terrestrially elusive {sup 244}Pu decay.

  10. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank

    2003-06-30

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Frank Rack, Anne Trehu, and Tim Collett presented preliminary results and operational outcomes of ODP Leg 204 at the American Association of Petroleum Geologists annual meeting in Salt Lake City, UT; (2) several Leg 204 scientists participated in special hydrate sessions at the international EGS/AGU/EUG meeting in Nice, France and presented initial science results from the cruise, which included outcomes arising from this cooperative agreement; and, (3) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. At the EGS/EUG/AGU meeting in Nice, France in April, Leg 204 Co-chiefs Anne Trehu and Gerhard Bohrmann, as well as ODP scientists Charlie Paull, Erwin Suess, and Jim Kennett, participated in a press conference on hydrates. The well-attended press conference entitled ''Gas Hydrates: Free methane found and controversy over the 'hydrate gun''' led to stories in Nature on-line and BBC radio, among others. There were six (6) oral and fifteen (15) poster presentations on ODP Leg 204 hydrate science at the EGS/AGU/EUG Meeting in Nice, France on April 6-11, 2003. This was a very strong showing at a meeting just over six month following the completion of the drilling cruise and highlighted many of the results of the leg, including the results obtained with instruments and equipment funded under this cooperative agreement. At the AAPG annual meeting in Salt Lake City, UT on May 11-14, 2003, Anne Trehu gave an oral presentation about the scientific results of Leg 204, and Frank Rack presented a poster outlining the operational and technical accomplishments. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

  11. Investigation into the semimagic nature of the tin isotopes through electromagnetic moments

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

    Allmond, J. M.; Stuchbery, A. E.; Galindo-Uribarri, A.; Padilla-Rodal, E.; Radford, D. C.; Batchelder, J. C.; Bingham, C. R.; Howard, M. E.; Liang, J. F.; Manning, B.; et al

    2015-10-19

    A complete set of electromagnetic moments, B(E2;0+1 2+1), Q(2+1), and g(2+1), have been measured from Coulomb excitation of semi-magic 112,114,116,118,120,122,124Sn (Z = 50) on natural carbon and titanium targets. The magnitude of the B(E2) values, measured to a precision of ~4%, disagree with a recent lifetime study [Phys. Lett. B 695, 110 (2011)] that employed the Doppler- shift attenuation method. The B(E2) values show an overall enhancement compared with recent theoretical calculations and a clear asymmetry about midshell, contrary to naive expectations. A new static electric quadrupole moment, Q(2+1), has been measured for 114Sn. The static quadrupole moments are generallymore »consistent with zero but reveal an enhancement near midshell; this had not been previously observed. The magnetic dipole moments are consistent with previous measurements and show a near monotonic decrease in value with neutron number. The current theory calculations fail to reproduce the electromagnetic moments of the tin isotopes. The role of 2p-2h and 4p-4h intruders, which are lowest in energy at mid shell and outside of current model spaces, needs to be investigated in the future.« less

  12. Tracing coalbed natural gas-coproduced water using stable isotopes of carbon

    SciTech Connect (OSTI)

    Sharma, S.; Frost, C.D. [University of Wyoming, Laramie, WY (United States). Dept. for Renewable Resources

    2008-03-15

    Recovery of hydrocarbons commonly is associated with coproduction of water. This water may be put to beneficial use or may be reinjected into subsurface aquifers. In either case, it would be helpful to establish a fingerprint for that coproduced water so that it may be tracked following discharge on the surface or reintroduction to geologic reservoirs. This study explores the potential of using {delta}{sup 13}C of dissolved inorganic carbon (DIC) of coalbed natural gas (CBNG) - coproduced water as a fingerprint of its origin and to trace its fate once it is disposed on the surface. Our initial results for water samples coproduced with CBNG from the Powder River Basin show that this water has strongly positive {delta}{sup 13}C(DIC) (12 parts per thousand to 22 parts per thousand) that is readily distinguished from the negative {delta}{sup 13}C of most surface and ground water (-8 parts per thousand to -11 parts per thousand). Furthermore, the DIC concentrations in coproduced water samples are also high (more than 100 mg C/L) compared to the 20 to 50 mg C/L in ambient surface and ground water of the region. The distinctively high {delta}{sup 13}C and DIC concentrations allow us to identify surface and ground water that have incorporated CBNG-coproduced water. Accordingly, we suggest that the {delta}{sup 13}C(DIC) and DIC concentrations of water can be used for long-term monitoring of infiltration of CBNG-coproduced water into ground water and streams. Our results also show that the {delta} {sup 13}C (DIC) of CBNG-coproduced water from two different coal zones are distinct leading to the possibility of using {delta}{sup 13}C(DIC) to distinguish water produced from different coal zones.

  13. Cumulative fission yields of short-lived isotopes under natural-abundance-boron-carbide-moderated neutron spectrum

    SciTech Connect (OSTI)

    Finn, Erin C.; Metz, Lori A.; Greenwood, Lawrence R.; Pierson, Bruce; Wittman, Richard S.; Friese, Judah I.; Kephart, Rosara F.

    2015-04-09

    The availability of gamma spectroscopy data on samples containing mixed fission products at short times after irradiation is limited. Due to this limitation, data interpretation methods for gamma spectra of mixed fission product samples, where the individual fission products have not been chemically isolated from interferences, are not well-developed. The limitation is particularly pronounced for fast pooled neutron spectra because of the lack of available fast reactors in the United States. Samples containing the actinide isotopes 233, 235, 238U, 237Np, and 239Pu individually were subjected to a 2$ pulse in the Washington State University 1 MW TRIGA reactor. To achieve a fission-energy neutron spectrum, the spectrum was tailored using a natural abundance boron carbide capsule to absorb neutrons in the thermal and epithermal region of the spectrum. Our tailored neutron spectrum is unique to the WSU reactor facility, consisting of a soft fission spectrum that contains some measurable flux in the resonance region. This results in a neutron spectrum at greater than 0.1 keV with an average energy of 70 keV, similar to fast reactor spectra and approaching that of 235U fission. Unique fission product gamma spectra were collected from 4 minutes to 1 week after fission using single-crystal high purity germanium detectors. Cumulative fission product yields measured in the current work generally agree with published fast pooled fission product yield values from ENDF/B-VII, though a bias was noted for 239Pu. The present work contributes to the compilation of energy-resolved fission product yield nuclear data for nuclear forensic purposes.

  14. Photochemical isotope separation

    DOE Patents [OSTI]

    Robinson, C.P.; Jensen, R.J.; Cotter, T.P.; Greiner, N.R.; Boyer, K.

    1987-04-28

    A process is described for separating isotopes by selective excitation of isotopic species of a volatile compound by tuned laser light. A highly cooled gas of the volatile compound is produced in which the isotopic shift is sharpened and defined. Before substantial condensation occurs, the cooled gas is irradiated with laser light precisely tuned to a desired wavelength to selectively excite a particular isotopic species in the cooled gas. The laser light may impart sufficient energy to the excited species to cause it to undergo photochemical reaction or even to photoionize. Alternatively, a two-photon irradiation may be applied to the cooled gas to induce photochemical reaction or photoionization. The process is particularly applicable to the separation of isotopes of uranium and plutonium. 8 figs.

  15. Laser isotope separation

    DOE Patents [OSTI]

    Robinson, C. Paul (Los Alamos, NM); Jensen, Reed J. (Los Alamos, NM); Cotter, Theodore P. (Munich, DE); Boyer, Keith (Los Alamos, NM); Greiner, Norman R. (Los Alamos, NM)

    1988-01-01

    A process and apparatus for separating isotopes by selective excitation of isotopic species of a volatile compound by tuned laser light. A highly cooled gas of the volatile compound is produced in which the isotopic shift is sharpened and defined. Before substantial condensation occurs, the cooled gas is irradiated with laser light precisely tuned to a desired wavelength to selectively excite a particular isotopic species in the cooled gas. The laser light may impart sufficient energy to the excited species to cause it to undergo photolysis, photochemical reaction or even to photoionize. Alternatively, a two-photon irradiation may be applied to the cooled gas to induce photolysis, photochemical reaction or photoionization. The process is particularly applicable to the separation of isotopes of uranium.

  16. Molecular and isotopic partitioning of low-molecular-weight hydrocarbons during migration and gas hydrate precipitation in deposits of a high-flux seepage site

    E-Print Network [OSTI]

    2010-01-01

    and stable isotope compositions of natural gas hydrates: acarbon isotopic composition of methane from natural gases of

  17. Perchlorate Isotope Forensics

    SciTech Connect (OSTI)

    Bohlke, J. K. [U.S. Geological Survey, Reston, VA; Sturchio, N. C. [University of Illinois, Chicago; Gu, Baohua [ORNL; Horita, Juske [ORNL; Brown, Gilbert M [ORNL; Jackson, W. Andrew [Tennessee Technological University; Batista, Jacimaria [University of Nevada, Las Vegas

    2006-01-01

    Perchlorate has been detected recently in a variety of soils, waters, plants, and food products at levels that may be detrimental to human health. These discoveries have generated considerable interest in perchlorate source identification. In this study, comprehensive stable isotope analyses ({sup 37}Cl/{sup 35}Cl and {sup 18}O/{sup 17}O/{sup 16}O) of perchlorate from known synthetic and natural sources reveal systematic differences in isotopic characteristics that are related to the formation mechanisms. In addition, isotopic analyses of perchlorate extracted from groundwater and surface water demonstrate the feasibility of identifying perchlorate sources in contaminated environments on the basis of this technique. Both natural and synthetic sources of perchlorate have been identified in water samples from some perchlorate occurrences in the United States by the isotopic method.

  18. Measurement of the cross sections for the production of the isotopes {sup 74}As, {sup 68}Ge, {sup 65}Zn, and {sup 60}Co from natural and enriched germanium irradiated with 100-MeV protons

    SciTech Connect (OSTI)

    Barabanov, I. R.; Bezrukov, L. B.; Gurentsov, V. I.; Zhuykov, B. L.; Kianovsky, S. V.; Kornoukhov, V. N.; Kohanuk, V. M.; Yanovich, E. A. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2010-07-15

    The cross sections for the production of the radioactive isotopes {sup 74}As, {sup 68}Ge, {sup 65}Zn, and {sup 60}Co in metallic germanium irradiated with 100-MeV protons were measured, the experiments being performed both with germanium of natural isotopic composition and germanium enriched in the isotope {sup 76}Ge. The targets were irradiated with a proton beam at the facility for the production of radionuclides at the accelerator of the Institute for Nuclear Research (INR, Moscow). The data obtained will further be used to calculate the background of radioactive isotopes formed by nuclear cascades of cosmic-ray muons in new-generation experiments devoted to searches for the neutrinoless double-beta decay of {sup 76}Ge at underground laboratories.

  19. Positive and inverse isotope effect on superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-04

    This article improves the BCS theory to include the inverse isotope effect on superconductivity. An affective model can be deduced from the model including electron-phonon interactions, and the phonon-induced attraction is simply and clearly explained on the electron Green function. The focus of this work is on how the positive or inverse isotope effect occurs in superconductors.

  20. Search for long-lived isomeric states in neutron-deficient thorium isotopes

    E-Print Network [OSTI]

    J. Lachner; I. Dillmann; T. Faestermann; G. Korschinek; M. Poutivtsev; G. Rugel

    2009-07-01

    The discovery of naturally occurring long-lived isomeric states (t_1/2 > 10^8 yr) in the neutron-deficient isotopes 211,213,217,218Th [A. Marinov et al., Phys. Rev. C 76, 021303(R) (2007)] was reexamined using accelerator mass spectrometry (AMS). Because AMS does not suffer from molecular isobaric background in the detection system, it is an extremely sensitive technique. Despite our up to two orders of magnitude higher sensitivity we cannot confirm the discoveries of neutron-deficient thorium isotopes and provide upper limits for their abundances.

  1. A Case where a Paradox Like Braess's Occurs in the Nash Equilibrium but Does Not Occur in the Wardrop Equilibrium

    E-Print Network [OSTI]

    A Case where a Paradox Like Braess's Occurs in the Nash Equilibrium but Does Not Occur of the other individuals. Another framework in which such a paradox may occur is that of the Nash equilibrium­ negligible eoeect on the other players. It is natural to expect the same type of paradox in the Nash equilib

  2. Stable Isotope Enrichment Capabilities at ORNL

    SciTech Connect (OSTI)

    Egle, Brian; Aaron, W Scott; Hart, Kevin J

    2013-01-01

    The Oak Ridge National Laboratory (ORNL) and the US Department of Energy Nuclear Physics Program have built a high-resolution Electromagnetic Isotope Separator (EMIS) as a prototype for reestablishing a US based enrichment capability for stable isotopes. ORNL has over 60 years of experience providing enriched stable isotopes and related technical services to the international accelerator target community, as well as medical, research, industrial, national security, and other communities. ORNL is investigating the combined use of electromagnetic and gas centrifuge isotope separation technologies to provide research quantities (milligram to several kilograms) of enriched stable isotopes. In preparation for implementing a larger scale production facility, a 10 mA high-resolution EMIS prototype has been built and tested. Initial testing of the device has simultaneously collected greater than 98% enriched samples of all the molybdenum isotopes from natural abundance feedstock.

  3. Isotopes Products

    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 likeUniverseIMPACT EVALUATIONIntroducing theActivation byIs a SmallIsotope

  4. The plasma centrifuge: A compact, low cost, stable isotope separator. Phase 2 final technical report, September 15, 1991--September 14, 1995

    SciTech Connect (OSTI)

    Guss, W.

    1996-09-05

    Enriched stable isotopes are required for production of radionuclides as well as for research and diagnostic uses. Science Research Laboratory (SRL) has developed a plasma centrifuge for moderate throughput of enriched stable isotopes, such as {sup 13}C, {sup 17}O, {sup 18}O, and {sup 203}Tl, for medical as well as other applications. Dwindling isotope stocks have restricted the use of enriched isotopes and their associated labeled organic molecules in medical imaging to very few research facilities because of high costs of isotope separation. With the introduction of the plasma centrifuge separator, the cost per separated gram of even rarely occurring isotopes ({le} 1% natural abundance) is potentially many times lower than with other separation technologies (cryogenic distillation and calutrons). The centrifuge is a simple, robust, pulsed electrical discharge device that has successfully demonstrated isotope separation of small (mg) quantities of {sup 26}Mg. Based on the results of the Phase 2 program, modest enhancements to the power supplies and cooling systems, a centrifuge separator will have high repetition rate (60 pps) and high duty cycle (60%) to produce in one month kilogram quantities of highly enriched stable isotopes. The centrifuge may be used in stand-alone operation or could be used as a high-throughput pre-separation stage with calutrons providing the final separation.

  5. Synthetic and Biosynthetic Studies of Natural Products

    E-Print Network [OSTI]

    Ve?liz Chanis, Eduardo Alberto

    1992-05-01

    of 4-Demethoxy -A-Homodaunorubicin Analogs Part II. Biosynthesis of Coloradocin. Origin of the Carbons Part III. Total Synthesis of the Naturally Occurring Prenylated Bibenzyl Amorfrutin A Eduardo Alberto Veliz Chanis B.S., University of Panama... to the intractable behavior of some of the intermediates. Part II describes the elucidation of the biosynthesis of coloradocin by the use of stable isotopes. The major carbon chain is polyketide and derived from acetate-propionate and methionine as shown...

  6. Isotope specific arbitrary material sorter

    DOE Patents [OSTI]

    Barty, Christopher P.J.

    2015-12-08

    A laser-based mono-energetic gamma-ray source is used to provide a rapid and unique, isotope specific method for sorting materials. The objects to be sorted are passed on a conveyor in front of a MEGa-ray beam which has been tuned to the nuclear resonance fluorescence transition of the desired material. As the material containing the desired isotope traverses the beam, a reduction in the transmitted MEGa-ray beam occurs. Alternately, the laser-based mono-energetic gamma-ray source is used to provide non-destructive and non-intrusive, quantitative determination of the absolute amount of a specific isotope contained within pipe as part of a moving fluid or quasi-fluid material stream.

  7. Naturally Occurring Melanin Synthesis Regulators and Their Modes of Action

    E-Print Network [OSTI]

    Satooka, Hiroki

    2011-01-01

    vivo hepatotoxicity caused by green tea phenolic acids andvivo hepatotoxicity caused by green tea phenolic acids andvivo hepatotoxicity caused by green tea phenolic acids and

  8. Naturally Occurring Melanin Synthesis Regulators and Their Modes of Action

    E-Print Network [OSTI]

    Satooka, Hiroki

    2011-01-01

    activity and mechanism of resveratrol- oriented analogues:trans- stilbene derivatives: resveratrol, pinosylvin and 4-Multiple molecular targets of resveratrol: Anti-carcinogenic

  9. Nonequilibrium clumped isotope signals in microbial methane

    E-Print Network [OSTI]

    Wang, David T.

    Methane is a key component in the global carbon cycle with a wide range of anthropogenic and natural sources. Although isotopic compositions of methane have traditionally aided source identification, the abundance of its ...

  10. AVLIS enrichment of medical isotopes

    SciTech Connect (OSTI)

    Haynam, C.A.; Scheibner, K.F.; Stern, R.C.; Worden, E.F.

    1996-12-31

    Under the Sponsorship of the United states Enrichment Corporation (USEC), we are currently investigating the large scale separation of several isotopes of medical interest using atomic vapor isotope separation (AVLIS). This work includes analysis and experiments in the enrichment of thallium 203 as a precursor to the production of thallium 201 used in cardiac imaging following heart attacks, on the stripping of strontium 84 from natural strontium as precursor to the production of strontium 89, and on the stripping of lead 210 from lead used in integrated circuits to reduce the number of alpha particle induced logic errors.

  11. 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.

  12. Isotopic Survey of Lake Davis and the Local Groundwater

    SciTech Connect (OSTI)

    Ridley, M N; Moran, J E; Singleton, M J

    2007-08-21

    In September 2007, California Fish and Game (CAFG) plans to eradicate the northern pike from Lake Davis. As a result of the eradication treatment, local residents have concerns that the treatment might impact the local groundwater quality. To address the concerns of the residents, Lawrence Livermore National Laboratory (LLNL) recommended measuring the naturally occurring stable oxygen isotopes in local groundwater wells, Lake Davis, and the Lake Davis tributaries. The purpose of these measurements is to determine if the source of the local groundwater is either rain/snowmelt, Lake Davis/Big Grizzly Creek water or a mixture of Lake Davis/Big Grizzly Creek and rain/snowmelt. As a result of natural evaporation, Lake Davis and the water flowing into Big Grizzly Creek are naturally enriched in {sup 18}oxygen ({sup 18}O), and if a source of a well's water is Lake Davis or Big Grizzly Creek, the well water will contain a much higher concentration of {sup 18}O. This survey will allow for the identification of groundwater wells whose water source is Lake Davis or Big Grizzly Creek. The results of this survey will be useful in the development of a water-quality monitoring program for the upcoming Lake Davis treatment. LLNL analyzed 167 groundwater wells (Table 1), 12 monthly samples from Lake Davis (Table 2), 3 samples from Lake Davis tributaries (Table 2), and 8 Big Grizzly Creek samples (Table 2). Of the 167 groundwater wells sampled and analyzed, only 2 wells contained a significant component of evaporated water, with an isotope composition similar to Lake Davis water. The other 163 groundwater wells have isotope compositions which indicate that their water source is rain/snowmelt.

  13. Nitrogen isotope dynamics of the Cariaco Basin, Venezuela Robert C. Thunell,1

    E-Print Network [OSTI]

    Sigman, Daniel M.

    Nitrogen isotope dynamics of the Cariaco Basin, Venezuela Robert C. Thunell,1 Daniel M. Sigman,2 of Venezuela. Water column denitrification occurring in the basin has only a very small isotopic imprint-Karger, Y. Astor, and R. Varela (2004), Nitrogen isotope dynamics of the Cariaco Basin, Venezuela, Global

  14. I ISOTOPES

    Office of Legacy Management (LM)

    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 NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and700, 1.Reports1E~ S·D3GraniteS T A TI*,Hov 2*

  15. Thermal neutron capture cross sections of tellurium isotopes

    SciTech Connect (OSTI)

    Tomandl, I.; Honzatko, J.; von Egidy, T.; Wirth, H.-F.; Belgya, T.; Lakatos, M.; Szentmiklosi, L.; Revay, Zs.; Molnar, G.L.; Firestone, R.B.; Bondarenko, V.

    2004-03-01

    New values for thermal neutron capture cross sections of the tellurium isotopes 122Te, 124Te, 125Te, 126Te, 128Te, and 130Te are reported. These values are based on a combination of newly determined partial g-ray cross sections obtained from experiments on targets contained natural Te and gamma intensities per capture of individual Te isotopes. Isomeric ratios for the thermal neutron capture on the even tellurium isotopes are also given.

  16. Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence

    SciTech Connect (OSTI)

    Berhanu, Tesfaye A.; Erbland, Joseph; Savarino, Joël [Laboratoire de Glaciologie et Géophysique de l’Environnement, CNRS, F-38041 Grenoble (France); Univ. Grenoble Alpes, LGGE, F-38041 Grenoble (France); Meusinger, Carl; Johnson, Matthew S. [Copenhagen Center for Atmospheric Research (CCAR), Department of Chemistry, University of Copenhagen, Copenhagen (Denmark); Jost, Rémy [Laboratoire de Interdisciplinaire de Physique (LIPHY) Univ. de Grenoble, Grenoble (France); Bhattacharya, S. K. [Research Center for Environmental Changes, Academia Sinica, Nangang, Taipei 115, Taiwan (China)

    2014-06-28

    Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. [“Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry,” J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate ({sup 15}N, {sup 17}O, and {sup 18}O) provide additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (?{sup 15}N, ?{sup 18}O, and ?{sup 17}O). From these measurements an average photolytic isotopic fractionation of {sup 15}? = (?15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wavelengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of {sup 15}? = (?47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from ?40 to ?74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of {sup 14}NO{sub 3}{sup ?} and {sup 15}NO{sub 3}{sup ?} in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying this model under the experimental temperature as well as considering the shift in width and center well reproduced the values obtained in the laboratory study. These cross sections can be used in isotopic models to reproduce the stable isotopic composition of nitrate found in Antarctic snow profiles.

  17. Elemental and isotopic analysis of inorganic salts by laser desorption ionization mass spectrometry

    SciTech Connect (OSTI)

    Jayasekharan, T.; Sahoo, N. K.

    2013-02-05

    Laser desorption ionization mass spectrometry is applied for the analysis of elements as well as their isotopic composition in different inorganic salts. At very low laser energies the inorganic ions are desorbed and ionized from the thin layer of the sample surface. The naturally occurring isotopes of alkali and silver ions are resolved using time of flight mass spectrometer. Further increase in laser energy shows the appearance of Al, Cr, and Fe ions in the mass spectra. This indicates the penetration laser beam beyond the sample surface leading to the ablation of sample target at higher energies. The simultaneous appearance of atomic ions from the sample target at relatively higher laser energies hampers the unambiguous identification of amino acid residues from the biomolecular ions in MALDI-MS.

  18. Environmental assessment: special isotope separation process selection

    SciTech Connect (OSTI)

    Not Available

    1986-04-01

    This Environmental Assessment (EA) evaluates the differences in potential environmental impacts between two plutonium Special Isotope Separation (SIS) technologies: Atomic Vapor Laser Isotope Separation (AVLIS) and Molecular Laser Isotope Separation (MLIS). Both SIS technologies use PuO/sub 2/ as feed; AVLIS converts feed to plutonium metal and MLIS converts feed to PuF/sub 6/. The AVLIS process uses laser energy to selectively photoionize and electrostatically separate plutonium isotopes from an atomic vapor stream. The MLIS process uses laser energy to selectively disassociate specific isotopes of plutonium in the form of PuF/sub 6/ molecules to create PuF/sub 5/ for collection and further processing. Both processes produce plutonium metal as their product. An evaluation of differences in potential environmental impacts attributed to the construction of an SIS facility, based on either technology, included a comparison of construction materials, land areas required, and the size of the design and construction workforce. The differences in potential environmental impacts from operating an SIS facility were also compared. No large differences in potential environmental impacts would be expected from the use of process chemicals. An AVLIS or an MLIS facility would produce operating effluents that would meet all applicable radiation, chemical, and hazardous waste standards and would be constructed to protect workers, the public and the environment. This EA has not revealed any significant differences in the potential environmental impacts that could occur as a result of deploying either the AVLIS or the MLIS Special Isotope Separation technology.

  19. Hybrid isotope separation scheme

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18

    A method is described for yielding selectively a desired enrichment in a specific isotope including the steps of inputting into a spinning chamber a gas from which a scavenger, radiating the gas with a wave length or frequency characteristic of the absorption of a particular isotope of the atomic or molecular gas, thereby inducing a photochemical reaction between the scavenger, and collecting the specific isotope-containing chemical by using a recombination surface or by a scooping apparatus. 2 figures.

  20. Stable isotope enrichment

    ScienceCinema (OSTI)

    Egle, Brian

    2014-07-15

    Brian Egle is working to increase the nation's capacity to produce stable isotopes for use including medicine, industry and national security.

  1. Stable isotope enrichment

    SciTech Connect (OSTI)

    Egle, Brian

    2014-07-14

    Brian Egle is working to increase the nation's capacity to produce stable isotopes for use including medicine, industry and national security.

  2. Price Quotes and Isotope Ordering

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

    Ordering Price Quotes and Isotope Ordering Isotopes produced at Los Alamos National Laboratory are saving lives, advancing cutting-edge research and keeping the U.S. safe. Isotope...

  3. Discovery of the Indium Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2010-09-08

    Thirty-eight indium isotopes (A = 98-135) have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  4. Discovery of the Titanium Isotopes

    E-Print Network [OSTI]

    D. Meierfrankenfeld; M. Thoennessen

    2010-09-08

    Twentyfive titanium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  5. Discovery of the Mercury Isotopes

    E-Print Network [OSTI]

    D. Meierfrankenfeld; M. Thoennessen

    2010-09-08

    Forty mercury isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  6. Discovery of the Cobalt Isotopes

    E-Print Network [OSTI]

    T. Szymanski; M. Thoennessen

    2009-09-04

    Twenty-six cobalt isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  7. Discovery of the Tin Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2010-09-08

    Thirty-eight tin isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  8. Discovery of the Cadmium Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2009-10-22

    Thirty-seven cadmium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  9. (Carbon isotope fractionation inplants)

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1990-01-01

    The objectives of this research are: To develop a theoretical and experimental framework for understanding isotope fractionations in plants; and to develop methods for using this isotope fractionation for understanding the dynamics of CO{sub 2} fixation in plants. Progress is described.

  10. Carbon isotope ratios of organic compound fractions in oceanic suspended particles

    E-Print Network [OSTI]

    Hwang, Jeomshik; Druffel, Ellen R. M

    2006-01-01

    Radiocarbon evidence of fossil-carbon cycling in sediments1968), Metabolic fractionation of carbon isotopes in marineof particulate organic carbon using bomb 14 C, Nature,

  11. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1986-08-15

    The atomic vapor laser isotope separation (AVLIS) process for the enrichment of uranium is evaluated. (AIP)

  12. Isotopic and geochemical tracers for U(VI) reduction and U mobility at an in situ recovery U mine

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

    Basu, Anirban; Brown, Shaun T.; Christensen, John N.; DePaolo, Donald J.; Reimus, Paul W.; Heikoop, Jeffrey M.; Woldegabriel, Giday; Simmons, Ardyth M.; House, Brian M.; Hartmann, Matt; et al

    2015-05-19

    In situ recovery (ISR) uranium (U) mining mobilizes U in its oxidized hexavalent form (U(VI)) by oxidative dissolution of U from the roll-front U deposits. Post-mining natural attenuation of residual U(VI) at ISR mines is a potential remediation strategy. Detection and monitoring of naturally occurring reducing subsurface environments are important for successful implementation of this remediation scheme. We used the isotopic tracers ²³?U/²³?U (?²³?U), ²³?U/²³?U activity ratio, and ³?S/³²S (?³?S), and geochemical measurements of U ore and groundwater collected from 32 wells located within, upgradient, and downgradient of a roll-front U deposit to detect U(VI) reduction and U mobility atmore »an ISR mining site at Rosita, TX, USA. The ?²³?U in Rosita groundwater varies from 0.61‰ to -2.49‰, with a trend toward lower ?²³?U in downgradient wells. The concurrent decrease in U(VI) concentration and ?²³?U with an ? of 0.48‰ ± 0.08‰ is indicative of naturally occurring reducing environments conducive to U(VI) reduction. Additionally, characteristic ²³?U/²³?U activity ratio and ?³?S values may also be used to trace the mobility of the ore zone groundwater after mining has ended. These results support the use of U isotope-based detection of natural attenuation of U(VI) at Rosita and other similar ISR mining sites.« less

  13. Coal fly ash interaction with environmental fluids: Geochemical and strontium isotope results from combined column and batch leaching experiments

    SciTech Connect (OSTI)

    Brubaker, Tonya M.; Stewart, Brian W.; Capo, Rosemary C.; Schroeder, Karl T.; Chapman, Elizabeth C.; Spivak-Birndorf, Lev J.; Vesper, Dorothy J.; Cardone, Carol R.; Rohar, Paul C.

    2013-05-01

    The major element and Sr isotope systematics and geochemistry of coal fly ash and its interactions with environmental waters were investigated using laboratory flow-through column leaching experiments (sodium carbonate, acetic acid, nitric acid) and sequential batch leaching experiments (water, acetic acid, hydrochloric acid). Column leaching of Class F fly ash samples shows rapid release of most major elements early in the leaching procedure, suggesting an association of these elements with soluble and surface bound phases. Delayed release of certain elements (e.g., Al, Fe, Si) signals gradual dissolution of more resistant silicate or glass phases as leaching continues. Strontium isotope results from both column and batch leaching experiments show a marked increase in {sup 87}Sr/{sup 86}Sr ratio with continued leaching, yielding a total range of values from 0.7107 to 0.7138. For comparison, the isotopic composition of fluid output from a fly ash impoundment in West Virginia falls in a narrow range around 0.7124. The experimental data suggest the presence of a more resistant, highly radiogenic silicate phase that survives the combustion process and is leached after the more soluble minerals are removed. Strontium isotopic homogenization of minerals in coal does not always occur during the combustion process, despite the high temperatures encountered in the boiler. Early-released Sr tends to be isotopically uniform; thus the Sr isotopic composition of fly ash could be distinguishable from other sources and is a useful tool for quantifying the possible contribution of fly ash leaching to the total dissolved load in natural surface and ground waters.

  14. Plasma isotope separation methods

    SciTech Connect (OSTI)

    Grossman, M.W. ); Shepp, T.A. )

    1991-12-01

    Isotope separation has many important industrial, medical, and research applications. Large-scale processes have typically utilized complex cascade systems; for example, the gas centrifuge. Alternatively, high single-stage enrichment processes (as in the case of the calutron) are very energy intensive. Plasma-based methods being developed for the past 15 to 20 years have attempted to overcome these two drawbacks. In this review, six major types of isotope separation methods which involve plasma phenomena are discussed. These methods are: plasma centrifuge, AVLIS (atomic vapor laser isotope separation), ion wave, ICR (ion-cyclotron resonance), calutron, and gas discharge. The emphasis of this paper is to describe the plasma phenomena in these major categories. An attempt was made to include enough references so that more detailed study or evaluation of a particular method could readily be pursued. A brief discussion of isotope separation using mass balance concepts is also carried out.

  15. How low-energy fusion can occur

    E-Print Network [OSTI]

    B. Ivlev

    2012-12-04

    Fusion of two deuterons of room temperature energy is discussed. The nuclei are in vacuum with no connection to any external source (electric or magnetic field, illumination, surrounding matter, traps, etc.) which may accelerate them. The energy of two nuclei is conserved and remains small during the motion through the Coulomb barrier. The penetration through this barrier, which is the main obstacle for low-energy fusion, strongly depends on a form of the incident flux on the Coulomb center at large distances from it. In contrast to the usual scattering, the incident wave is not a single plane wave but the certain superposition of plane waves of the same energy and various directions, for example, a convergent conical wave. The wave function close to the Coulomb center is determined by a cusp caustic which is probed by de Broglie waves. The particle flux gets away from the cusp and moves to the Coulomb center providing a not small probability of fusion (cusp driven tunneling). Getting away from a caustic cusp also occurs in optics and acoustics.

  16. Heavy-atom isotope effects on the acid-catalyzed hydrolysis of methyl benzoate

    SciTech Connect (OSTI)

    Marlier, J.F.; O'Leary, M.H.

    1981-05-08

    Results of the use of a previously reported technique of four-heavy atom isotope effects for study of the acid-catalyzed hydrolysis of methyl benzoate are reported. Ether oxygen and methyl carbon isotope effects on the reaction were measured by the usual natural-abundance isotope-ratio technique. The carbonyl oxygen isotope effect was measured by the pseudo-natural-abundance double-label method as was the carbonyl carbon isotope effect. The results led to the assumption that the hydrolysis of methyl benzoate proceeds by way of a tetrahedral intermediate. The small amount of oxygen exchange with the solvent that accompanies the hydrolysis indicated that it is intermediate formation rather than decomposition that is rate determining. The small magnitude of the observed carbon isotope effect on the acid-catalyzed hydrolysis of methyl benzoate compared to carbon isotope effects on other reactions of this compound indicate that the transition state is relatively reactant-like. (BLM)

  17. Apparatus for storing hydrogen isotopes

    DOE Patents [OSTI]

    McMullen, John W. (Los Alamos, NM); Wheeler, Michael G. (Los Alamos, NM); Cullingford, Hatice S. (Houston, TX); Sherman, Robert H. (Los Alamos, NM)

    1985-01-01

    An improved method and apparatus for storing isotopes of hydrogen (especially tritium) are provided. The hydrogen gas(es) is (are) stored as hydrides of material (for example uranium) within boreholes in a block of copper. The mass of the block is critically important to the operation, as is the selection of copper, because no cooling pipes are used. Because no cooling pipes are used, there can be no failure due to cooling pipes. And because copper is used instead of stainless steel, a significantly higher temperature can be reached before the eutectic formation of uranium with copper occurs, (the eutectic of uranium with the iron in stainless steel forming at a significantly lower temperature).

  18. Transportation of medical isotopes

    SciTech Connect (OSTI)

    Nielsen, D.L.

    1997-11-19

    A Draft Technical Information Document (HNF-1855) is being prepared to evaluate proposed interim tritium and medical isotope production at the Fast Flux Test Facility (FFTF). This assessment examines the potential health and safety impacts of transportation operations associated with the production of medical isotopes. Incident-free and accidental impacts are assessed using bounding source terms for the shipment of nonradiological target materials to the Hanford Site, the shipment of irradiated targets from the FFTF to the 325 Building, and the shipment of medical isotope products from the 325 Building to medical distributors. The health and safety consequences to workers and the public from the incident-free transportation of targets and isotope products would be within acceptable levels. For transportation accidents, risks to works and the public also would be within acceptable levels. This assessment is based on best information available at this time. As the medical isotope program matures, this analysis will be revised, if necessary, to support development of a final revision to the Technical Information Document.

  19. Atomic vapor laser isotope separation of lead-210 isotope

    DOE Patents [OSTI]

    Scheibner, Karl F. (Tracy, CA); Haynam, Christopher A. (Pleasanton, CA); Johnson, Michael A. (Pleasanton, CA); Worden, Earl F. (Diablo, CA)

    1999-01-01

    An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207.

  20. Atomic vapor laser isotope separation of lead-210 isotope

    DOE Patents [OSTI]

    Scheibner, K.F.; Haynam, C.A.; Johnson, M.A.; Worden, E.F.

    1999-08-31

    An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207. 5 figs.

  1. Method for separating boron isotopes

    DOE Patents [OSTI]

    Rockwood, Stephen D. (Los Alamos, NM)

    1978-01-01

    A method of separating boron isotopes .sup.10 B and .sup.11 B by laser-induced selective excitation and photodissociation of BCl.sub.3 molecules containing a particular boron isotope. The photodissociation products react with an appropriate chemical scavenger and the reaction products may readily be separated from undissociated BCl.sub.3, thus effecting the desired separation of the boron isotopes.

  2. Evaluating patterns of fog water deposition and isotopic composition on the California Channel Islands

    E-Print Network [OSTI]

    Fischer, Douglas T; Still, Christopher J.

    2007-01-01

    relative proportions of fog and rain water when they occurIsotopic composition of fog and rain water at Site 7. “Fog”are a mixture of fog and rain water. Dry season fog water is

  3. Isotop kl. B Supportlab.

    E-Print Network [OSTI]

    Isotop kl. B lab. Nærlager Supportlab. Supportlab. Supportlab. Lab. GMO1/BSL2 Supportlab. Supportlab. Supportlab. Supportlab. Lab. GMO1/BSL2 Vareindlevering post/frost Kontor Sofastue / Thekøkken. GMO1/BSL2 Supportlab. �velseslab, eksist. �velseslab, eksist. Forberedelseslab. Rum, køl/ centrifuge

  4. Studies of isotopic exchange between gaseous hydrogen and palladium hydride powder

    SciTech Connect (OSTI)

    Foltz, G.W.; Melius, C.F.

    1987-12-01

    A gas flow apparatus has been constructed and used to study the isotopic exchange reaction occurring between the solid and gas phases in hydrogen (deuterium) gas flows directed through packed-powder beds of ..beta..-phase palladium deuteride (hydride). Spontaneous Raman light scattering is employed to obtain a real-time analysis of the isotopic composition of the gas (H/sub 2/, D/sub 2/, HD) exiting from the bed. A parametric rate-equation model is described which depicts the time-dependent behavior of the isotopic exchange process. The exchange mechanism is assumed to be rate-limited by processes occurring on the surface of the powder. The fundamental kinetic parameter of the model is the isotopic exchange probability, p, which is the probability that an isotopic exchange event occurs during a collision of a gas-phase atom with the surface. Isotope effects between the gas and solid phases are explicitly included in terms of the isotope separation factor, ..cap alpha... Results of the model are compared with the experimental measurements and, using a literature value of ..cap alpha.. = 2.4, good agreement is obtained for p approx. = 10/sup -7/. In view of the importance of the isotope effects in the hydrogen/palladium system and the range of a values reported for the ..beta..-phase in the literature, the sensitivity of the model results to a variation in the value of ..cap alpha.. is examined.

  5. Identification of the source of methane at a hazardous waste treatment facility using isotopic analysis

    SciTech Connect (OSTI)

    Hackley, K.C.; Liu, C.L. (Illinois State Geological Survey, Peabody, IL (United States)); Trainor, D.P. (Dames and Moore, Madison, WI (United States))

    1992-01-01

    Isotopic analyses have been used to determine the source of methane in subsurface sediments at a hazardous waste treatment facility in the Lake Calumet area of Chicago, Illinois. The study area is surrounded by landfills and other waste management operations and has a long history of waste disposal. The facility property consists of land constructed of approximately 15 feet of fill placed over lake sediments. The fill is underlain by successively older lacustrine and glacial till deposits to a maximum depth of approximately 80 feet. During a subsurface investigation of the site performed for a RCRA Facility Investigation of former solid waste management units (SWMUs) in the fill, significant quantities of methane were encountered in the natural deposits. Gas samples were collected from the headspace of 11 piezometers screened at depths of approximately 30, 40, and 50 feet beneath the surface. Methane concentrations up to 75% by volume were observed in some of the piezometers. Stable isotope analyses were completed on methane and associated CO[sub 2] separated from the gas samples. Radiocarbon (C-14) analyses were also completed on several of the samples. The delta C-13 results for the intermediate and deep zones are indicative of methane produced by microbial reduction of CO[sub 2]. The methane occurring in the shallow zone appears to be a mixture of methane from the intermediate zone and methane produced by microbial fermentation of naturally (nonanthropogenic) buried organic matter within the shallow lacustrine sediments. According to the isotopic and chemical results, the methane does not appear to be related to gas generation from nearby landfills or from organic wastes previously placed in the former facility SWMUs.

  6. METALLICITY-DEPENDENT GALACTIC ISOTOPIC DECOMPOSITION FOR NUCLEOSYNTHESIS

    SciTech Connect (OSTI)

    West, Christopher; Heger, Alexander, E-mail: west0482@umn.edu, E-mail: alexander.heger@monash.edu [Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

    2013-09-01

    All stellar evolution models for nucleosynthesis require an initial isotopic abundance set to use as a starting point. Generally, our knowledge of isotopic abundances of stars is fairly incomplete except for the Sun. We present a first model for a complete average isotopic decomposition as a function of metallicity. Our model is based on the underlying nuclear astrophysics processes, and is fitted to observational data, rather than traditional forward galactic chemical evolution modeling which integrates stellar yields beginning from big bang nucleosynthesis. We first decompose the isotopic solar abundance pattern into contributions from astrophysical sources. Each contribution is then assumed to scale as a function of metallicity. The resulting total isotopic abundances are summed into elemental abundances and fitted to available halo and disk stellar data to constrain the model's free parameter values. This procedure allows us to use available elemental observational data to reconstruct and constrain both the much needed complete isotopic evolution that is not accessible to current observations, and the underlying astrophysical processes. As an example, our model finds a best fit for Type Ia contributing {approx_equal} 0.7 to the solar Fe abundance, and Type Ia onset occurring at [Fe/H] {approx_equal} -1.1, in agreement with typical values.

  7. Laser isotope separation of erbium and other isotopes

    DOE Patents [OSTI]

    Haynam, C.A.; Worden, E.F.

    1995-08-22

    Laser isotope separation is accomplished using at least two photoionization pathways of an isotope simultaneously, where each pathway comprises two or more transition steps. This separation method has been applied to the selective photoionization of erbium isotopes, particularly for the enrichment of {sup 167}Er. The hyperfine structure of {sup 167}Er was used to find two three-step photoionization pathways having a common upper energy level. 3 figs.

  8. Laser isotope separation of erbium and other isotopes

    DOE Patents [OSTI]

    Haynam, Christopher A. (3035 Ferdale Ct., Pleasanton, CA 94566); Worden, Earl F. (117 Vereda del Ciervo, Diablo, CA 94528)

    1995-01-01

    Laser isotope separation is accomplished using at least two photoionization pathways of an isotope simultaneously, where each pathway comprises two or more transition steps. This separation method has been applied to the selective photoionization of erbium isotopes, particularly for the enrichment of .sup.167 Er. The hyperfine structure of .sup.167 Er was used to find two three-step photoionization pathways having a common upper energy level.

  9. Isotopic composition of passively collected nitrogen dioxide emissions: Vehicle, soil and livestock source signatures

    E-Print Network [OSTI]

    Elliott, Emily M.

    and d18 O values of natural and anthropogenic NOx emission sources. We report the first d15 N and d18 and vehicle emissions. We provide evidence for passive sampler use to collect NOx for isotope analysis. a r Accepted 7 April 2014 Available online 8 April 2014 Keywords: Nitrogen dioxide NOx Isotope Emission a b

  10. Isotopically labeled compositions and method

    DOE Patents [OSTI]

    Schmidt, Jurgen G. (Los Alamos, NM); Kimball, David B. (Los Alamos, NM); Alvarez, Marc A. (Santa Fe, NM); Williams, Robert F. (Los Alamos, NM); Martinez, Rudolfo A. (Santa Fe, NM)

    2011-07-12

    Compounds having stable isotopes .sup.13C and/or .sup.2H were synthesized from precursor compositions having solid phase supports or affinity tags.

  11. Descriptions of selected accidents that have occurred at nuclear reactor facilities

    SciTech Connect (OSTI)

    Bertini, H.W.

    1980-04-01

    This report was prepared at the request of the President's Commission on the Accident at Three Mile Island to provide the members of the Commission with some insight into the nature and significance of accidents that have occurred at nuclear reactor facilities in the past. Toward that end, this report presents a brief description of 44 accidents which have occurred throughout the world and which meet at least one of the severity criteria that were established.

  12. Rare Isotopes in Cosmic Explosions and Accelerators on Earth

    ScienceCinema (OSTI)

    Schatz, Hendrick [Michigan State University, East Lansing, Michigan, United States

    2010-01-08

    Rare isotopes are nature?s stepping stones to produce the heavy elements, and they are produced in large quantities in stellar explosions. Despite their fleeting existence, they shape the composition of the universe and the observable features of stellar explosions. The challenge for nuclear science is to produce and study the very same rare isotopes so as to understand the origin of the elements and a range of astronomical observations. I will review the progress that has been made to date in astronomy and nuclear physics, and the prospects of finally addressing many of the outstanding issues with the future Facility for Rare Isotope Beams (FRIB), which DOE will build at Michigan State University.

  13. RADIOCHEMICAL STUDIES OF NEUTRON DEFICIENT ACTINIDE ISOTOPES

    E-Print Network [OSTI]

    Williams, Kimberly Eve

    2011-01-01

    Isotope Targets and Foils, AERE-R 5097, Paper 10 (1965). V.Isotope Targets and Foils, AERE-R 5097 Paper 12 (1965). K.M.Isotope Targets and Foils, AERE-R-5097 Paper 11 (1965). M.

  14. Advanced isotope separation

    SciTech Connect (OSTI)

    Not Available

    1982-05-04

    The Study Group briefly reviewed the technical status of the three Advanced Isotope Separation (AIS) processes. It also reviewed the evaluation work that has been carried out by DOE's Process Evaluation Board (PEB) and the Union Carbide Corporation-Nuclear Division (UCCND). The Study Group briefly reviewed a recent draft assessment made for DOE staff of the nonproliferation implications of the AIS technologies. The staff also very briefly summarized the status of GCEP and Advanced Centrifuge development. The Study Group concluded that: (1) there has not been sufficient progress to provide a firm scientific, technical or economic basis on which to select one of the three competing AIS processes for full-scale engineering development at this time; and (2) however, should budgetary restraints or other factors force such a selection, we believe that the evaluation process that is being carried out by the PEB provides the best basis available for making a decision. The Study Group recommended that: (1) any decisions on AIS processes should include a comparison with gas centrifuge processes, and should not be made independently from the plutonium isotope program; (2) in evaluating the various enrichment processes, all applicable costs (including R and D and sales overhead) and an appropriate discounting approach should be included in order to make comparisons on a private industry basis; (3) if the three AIS programs continue with limited resources, the work should be reoriented to focus only on the most pressing technical problems; and (4) if a decision is made to develop the Atomic Vapor Laser Isotope Separation process, the solid collector option should be pursued in parallel to alleviate the potential program impact of liquid collector thermal control problems.

  15. Isotope effect studies of the pyridoxal 5'-phosphate dependent histidine decarboxylase from Morganella morganii

    SciTech Connect (OSTI)

    Abell, L.M.; O'Leary, M.H.

    1988-08-09

    The pyridoxal 5'-phosphate dependent histidine decarboxylase from Morganella morganii shows a nitrogen isotope effect k/sup 14//k/sup 15/ = 0.9770 +/- 0.0021, a carbon isotope effect k/sup 12//k/sup 13/ = 1.0308 +/- 0.0006, and a carbon isotope effect for L-(..cap alpha..-/sup 2/H)histidine of 1.0333 +/- 0.0001 at pH 6.3, 37/sup 0/C. These results indicate that the overall decarboxylation rate is limited jointly by the rate of Schiff base interchange and by the rate of decarboxylation. Although the observed isotope effects are quite different from those for the analogous glutamate decarboxylase from Escherichia coli, the intrinsic isotope effects for the two enzymes are essentially the same. The difference in observed isotope effects occurs because of a roughly twofold difference in the partitioning of the pyridoxal 5'-phosphate-substrate Schiff base between decarboxylation and Schiff base interchange. The observed nitrogen isotope effect requires that the imine nitrogen in this Schiff base is protonated. Comparison of carbon isotope effects for deuteriated and undeuteriated substrates reveals that the deuterium isotope effect on the decarboxylation step is about 1.20; thus, in the transition state for the decarboxylation step, the carbon-carbon bond is about two-thirds broken.

  16. The marine biogeochemistry of zinc isotopes

    E-Print Network [OSTI]

    John, Seth G

    2007-01-01

    Zinc (Zn) stable isotopes can record information about important oceanographic processes. This thesis presents data on Zn isotopes in anthropogenic materials, hydrothermal fluids and minerals, cultured marine phytoplankton, ...

  17. Isotope Research 229 Th production

    E-Print Network [OSTI]

    Isotope Research ­ 229 Th production We recently completed an ARRA-funded project of this type on 229 Th production reactions [Str11]. This long-lived isotope is important as a precursor to 225 Ac of accelerator production of 229 Th via the 230 Th(p,2n)229 Pa reaction. The 229 Pa decays primarily by electron

  18. A Comparison of Shell Model Results for Some properties of the Even-Even Ge Isotopes

    E-Print Network [OSTI]

    S. J. Q. Robinson; L. Zamick; Y. Y. Sharon

    2010-07-13

    In this work we examine two recent effective shell model interactions, JUN45 and JJ4B, that have been proposed for use in the $f_{5/2},p_{3/2}, p_{1/2}, g_{9/2}$ model space for both protons and neutrons. We calculate a number of quantities that did not enter into the fits undertaken to fix the parameters of both interactions. In particular we consider static quadrupole moments (Q's) of excited states of the even-even $^{70-76}$Ge isotopes, as well as the B(E2) values in these nuclei. (We have previously studied $^{70}$Zn isotopes using JJ4B.) Some striking disagreements between the JUN45 prediction and the experimental results had already been noted for the quadrupole moments of the $2_1^+$ states of these nuclei. We investigate whether these discrepancies also occur for the JJ4B interaction. Subsequently, we also apply both interactions to calculate the Q's of some more highly excited states and compare the two sets of predictions regarding the nature of the nuclear states under consideration. In order to gain insight into these more complex large-scale shell-model calculations, we examine the corresponding and much simpler single-j shell model calculations in the $g_{9/2}$ neutron shell.

  19. Unusual Intramolecular Kinetic Isotope Effects: Selectivity beyond Transition State Theory’s Jurisdiction 

    E-Print Network [OSTI]

    Andujar-De Sanctis, Ivonne

    2014-10-16

    The nature of non-statistical dynamic Kinetic Isotope Effects for a series of ordinary organic reactions is studied throughout this dissertation. A combination of experimental intramolecular KIEs using NMR methodology with ...

  20. Determining Planes Along Which Earthquakes Occur- Method of Applicatio...

    Open Energy Info (EERE)

    of earthquake locations is often so smeared that the underlying fault or joint structures along which the earthquakes occur cannot be inferred from visual inspection of...

  1. Jet-like circulations occur in the `simple' geometries of gas planets and Earth's

    E-Print Network [OSTI]

    #12;Jet-like circulations occur in the `simple' geometries of gas planets and Earth's liquid to barotropize jets => life cycles of BC instability. large-scale PV gradients act as source of eddy entrophy The Jet Stream Conundrum Baldwin, Rhines, Huang & McIntyre, Nature 2007 #12;For Earth's oceans, density

  2. Laser separation of medical isotopes

    SciTech Connect (OSTI)

    Eerkens, J.W.; Puglishi, D.A.; Miller, W.H.

    1996-12-31

    There is an increasing demand for different separated isotopes as feed material for reactor and cyclotron-produced radioisotopes used by a fast-growing radiopharmaceutical industry. One new technology that may meet future demands for medical isotopes is molecular laser isotope separation (MLIS). This method was investigated for the enrichment of uranium in the 1970`s and 1980s by Los Alamos National Laboratory, Isotope Technologies, and others around the world. While South Africa and Japan have continued the development of MLIS for uranium and are testing pilot units, around 1985 the United States dropped the LANL MLIS program in favor of AVLIS (atomic vapor LIS), which uses electron-beam-heated uranium metal vapor. AVLIS appears difficult and expensive to apply to most isotopes of medical interest, however, whereas MLIS technology, which is based on cooled hexafluorides or other gaseous molecules, can be adapted more readily. The attraction of MLIS for radiopharmaceutical firms is that it allows them to operate their own dedicated separators for small-quantity productions of critical medical isotopes, rather than having to depend on large enrichment complexes run by governments, which are only optimal for large-quantity productions. At the University of Missouri, the authors are investigating LIS of molybdenum isotopes using MoF{sub 6}, which behaves in a way similar to UF{sub 6}, studied in the past.

  3. Apparatus and process for separating hydrogen isotopes

    DOE Patents [OSTI]

    Heung, Leung K; Sessions, Henry T; Xiao, Xin

    2013-06-25

    The apparatus and process for separating hydrogen isotopes is provided using dual columns, each column having an opposite hydrogen isotopic effect such that when a hydrogen isotope mixture feedstock is cycled between the two respective columns, two different hydrogen isotopes are separated from the feedstock.

  4. Compelling Research Opportunities using Isotopes

    SciTech Connect (OSTI)

    2009-04-23

    Isotopes are vital to the science and technology base of the US economy. Isotopes, both stable and radioactive, are essential tools in the growing science, technology, engineering, and health enterprises of the 21st century. The scientific discoveries and associated advances made as a result of the availability of isotopes today span widely from medicine to biology, physics, chemistry, and a broad range of applications in environmental and material sciences. Isotope issues have become crucial aspects of homeland security. Isotopes are utilized in new resource development, in energy from bio-fuels, petrochemical and nuclear fuels, in drug discovery, health care therapies and diagnostics, in nutrition, in agriculture, and in many other areas. The development and production of isotope products unavailable or difficult to get commercially have been most recently the responsibility of the Department of Energy's Nuclear Energy program. The President's FY09 Budget request proposed the transfer of the Isotope Production program to the Department of Energy's Office of Science in Nuclear Physics and to rename it the National Isotope Production and Application program (NIPA). The transfer has now taken place with the signing of the 2009 appropriations bill. In preparation for this, the Nuclear Science Advisory Committee (NSAC) was requested to establish a standing subcommittee, the NSAC Isotope Subcommittee (NSACI), to advise the DOE Office of Nuclear Physics. The request came in the form of two charges: one, on setting research priorities in the short term for the most compelling opportunities from the vast array of disciplines that develop and use isotopes and two, on making a long term strategic plan for the NIPA program. This is the final report to address charge 1. NSACI membership is comprised of experts from the diverse research communities, industry, production, and homeland security. NSACI discussed research opportunities divided into three areas: (1) medicine, pharmaceuticals, and biology, (2) physical sciences and engineering, and (3) national security and other applications. In each area, compelling research opportunities were considered and the subcommittee as a whole determined the final priorities for research opportunities as the foundations for the recommendations. While it was challenging to prioritize across disciplines, our order of recommendations reflect the compelling research prioritization along with consideration of time urgency for action as well as various geopolitical market issues. Common observations to all areas of research include the needs for domestic availability of crucial stable and radioactive isotopes and the education of the skilled workforce that will develop new advances using isotopes in the future. The six recommendations of NSACI reflect these concerns and the compelling research opportunities for potential new discoveries. The science case for each of the recommendations is elaborated in the respective chapters.

  5. Raman scattering method and apparatus for measuring isotope ratios and isotopic abundances

    DOE Patents [OSTI]

    Harney, Robert C. (5665 Charlotte Way, No. 80, Livermore, CA 94550); Bloom, Stewart D. (141 Via Serena, Alamo, CA 94507)

    1978-01-01

    Raman scattering is used to measure isotope ratios and/or isotopic abundances. A beam of quasi-monochromatic photons is directed onto the sample to be analyzed, and the resulting Raman-scattered photons are detected and counted for each isotopic species of interest. These photon counts are treated mathematically to yield the desired isotope ratios or isotopic abundances.

  6. Modeling of temporal behavior of isotopic exchange between gaseous hydrogen and palladium hydride power

    SciTech Connect (OSTI)

    Melius, C F; Foltz, G W

    1987-01-01

    A parametric rate-equation model is described which depicts the time dependent behavior of the isotopic exchange process occurring between the solid and gas phases in gaseous hydrogen (deuterium) flows through packed-powder palladium deuteride (hydride) beds. The exchange mechanism is assumed to be rate-limited by processes taking place on the surface of the powder. The fundamental kinetic parameter of the model is the isotopic exchange probability, p, which is the probability that an isotopic exchange event occurs during a collision of a gas phase atom with the surface. Isotope effects between the gas and solid phases are explicitly included in terms of the isotope separation factor, ..cap alpha... Results of the model are compared with recent experimental measurements of isotope exchange in the ..beta..-phase hydrogen/palladium system and, using a literature value of ..cap alpha.. = 2.4, a good description of the experimental data is obtained for p approx. 10/sup -7/. In view of the importance of the isotope effects in the hydrogen/palladium system and the range of ..cap alpha.. values reported for the ..beta..-phase in the literature, the sensitivity of the model results to a variation in the value of ..cap alpha.. is examined.

  7. In-situ remediation of naturally occurring radioactive materials with high-permeability hydraulic fracturing 

    E-Print Network [OSTI]

    Demarchos, Andronikos Stavros

    1998-01-01

    in the petroleum industry, is the recommended technique. NORM are found throughout subterranean formations. Whenever fluids from petroleum or water reservoirs are produced NORM are present in varying quantities. NORM can only be sensed with radiation detectors...

  8. Roles of Naturally Occurring Bacteria in Controlling Iodine-129 Mobility in Subsurface Soils 

    E-Print Network [OSTI]

    Li, Hsiu-Ping

    2012-10-19

    (IO3-) and is the predominant species in the terrestrial environment due to prevailing pH and Eh conditions. In order to transform I- to less mobile organo-iodine (OI), strong oxidants are necessary to activate the first electron transfer step from I...

  9. The role of naturally occurring waterholes in determining the distribution of Florida Key Deer 

    E-Print Network [OSTI]

    Kim, Ji Yeon

    2009-05-15

    (Big Pine Key Inn Station, 1953) Data on Big Pine Key and the Volume of Daily Fresh Water Shortage on Big Pine Key (From the Result of 1-Year Base Line Simulation)................................................................................ 26...). I used two precipitation data sets to parameterize dv1, one consisting of daily precipitation (inches) from January 1 to December 31, 1953 from the Big Pine Key Inn weather station and one from January 1 to December 31, 2001 from the Key West...

  10. USE OF NATURALLY-OCCURRING TRACERS TO MONITOR TWO-PHASE CONDITIONS IN THE

    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:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin Film SolarTown(LECBP)BioGen LLC JumpForestryForm12 JumpCOSO EGS

  11. IUPAC Periodic Table of Isotopes for the Educational Community

    SciTech Connect (OSTI)

    Holden N. E.; Holden,N.E.; Coplen,T.B.

    2012-07-15

    John Dalton first proposed the concept of atomic weights of the elements in the first decade of the nineteenth century. These atomic weights of the chemical elements were thought of as constants of nature, similar to the speed of light. Dmitri Mendeleev arranged the atomic weights of the elements in ascending order of value and used the systematic variation of their chemical properties to produce his Periodic Table of the Elements in 1869. Measurement of atomic weight values became an important chemical activity for a century and a half. Theodore Richards received a Noble Prize for his work in this area. In 1913, Fredrick Soddy found a species of radium, which had an atomic weight value of 228, compared to the familiar radium gas value of 226. Soddy coined the term 'isotope' (Greek for 'in the same place') to account for this second atomic weight value in the radium position of the Periodic Table. Both of these isotopes of radium are radioactive. Radioactive isotopes are energetically unstable and will decay (disintegrate) over time. The time it takes for one half of a sample of a given radioactive isotope to decay is the half-life of that isotope. In addition to having different atomic weight values, radium-226 and radium-228 also have different half-life values. Around the same time as Soddy's work, J.J. Thomson (discoverer of the electron) identified two stable (non-radioactive) isotopes of the same element, neon. Over the next 40 years, the majority of the known chemical elements were found to have two or more stable (or long-lived radioactive isotopes that contribute significantly to the determination of the atomic weights of the elements).

  12. Novel hybrid isotope separation scheme and apparatus

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18

    A method is described for yielding selectively a desired enrichment in a specific isotope including the steps of inputting into a spinning chamber a gas from which the specific isotope is to be isolated, radiating the gas with frequencies characteristic of the absorption of a particular isotope of the atomic or molecular gas, thereby inducing a photoionization reaction of the desired isotope, and collecting the specific isotope ion by suitable ion collection means. 3 figures.

  13. Physics with isotopically controlled semiconductors

    SciTech Connect (OSTI)

    Haller, E. E., E-mail: eehaller@lbl.gov [University of California at Berkeley, Department of Materials Science and Engineering (United States)

    2010-07-15

    This paper is based on a tutorial presentation at the International Conference on Defects in Semiconductors (ICDS-25) held in Saint Petersburg, Russia in July 2009. The tutorial focused on a review of recent research involving isotopically controlled semiconductors. Studies with isotopically enriched semiconductor structures experienced a dramatic expansion at the end of the Cold War when significant quantities of enriched isotopes of elements forming semiconductors became available for worldwide collaborations. Isotopes of an element differ in nuclear mass, may have different nuclear spins and undergo different nuclear reactions. Among the latter, the capture of thermal neutrons which can lead to neutron transmutation doping, is the most prominent effect for semiconductors. Experimental and theoretical research exploiting the differences in all the properties has been conducted and will be illustrated with selected examples.

  14. Thermal Neutron Capture Cross Sections of the Palladium Isotopes

    E-Print Network [OSTI]

    2006-01-01

    CROSS SECTIONS OF THE PALLADIUM ISOTOPES R.B. Firestone ? ,? ? for all stable Palladium isotopes with the guidedscheme is complete. The Palladium isotope decay schemes are

  15. Isotope production facility produces cancer-fighting actinium

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

    Cancer therapy gets a boost from new isotope Isotope production facility produces cancer-fighting actinium A new medical isotope project shows promise for rapidly producing major...

  16. Significance of Isotopically Labile Organic Hydrogen in Thermal Maturation of Organic Matter

    SciTech Connect (OSTI)

    Arndt Schimmelmann; Maria Mastalerz

    2010-03-30

    Isotopically labile organic hydrogen in fossil fuels occupies chemical positions that participate in isotopic exchange and in chemical reactions during thermal maturation from kerogen to bitumen, oil and gas. Carbon-bound organic hydrogen is isotopically far less exchangeable than hydrogen bound to nitrogen, oxygen, or sulfur. We explore why organic hydrogen isotope ratios express a relationship with organic nitrogen isotope ratios in kerogen at low to moderate maturity. We develop and apply new techniques to utilize organic D/H ratios in organic matter fractions and on a molecular level as tools for exploration for fossil fuels and for paleoenvironmental research. The scope of our samples includes naturally and artificially matured substrates, such as coal, shale, oil and gas.

  17. FISH AND SHRIMP MIGRATIONS IN THE NORTHERN GULF OF MEXICO ANALYZED USING STABLE C,N, ANDS ISOTOPE RATIOS1

    E-Print Network [OSTI]

    FISH AND SHRIMP MIGRATIONS IN THE NORTHERN GULF OF MEXICO ANALYZED USING STABLE C,N, ANDS ISOTOPE RATIOS1 BRIAN FRY' ABSTRACT Natural stable isotope tags were used in the northern GulfofMexico to interpret migrations offive commer- cial fish and shrimp species: Leiostomus xanthurus, Micropogonias undu

  18. Diffusion in silicon isotope heterostructures

    SciTech Connect (OSTI)

    Silvestri, Hughes Howland

    2004-05-14

    The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the dopant diffusion mechanisms, the native defect charge states, and the self- and dopant diffusion coefficients can be determined. This information is necessary to enhance the physical modeling of dopant diffusion in Si. It is of particular interest to the modeling of future electronic Si devices, where the nanometer-scale features have created the need for precise physical models of atomic diffusion in Si. The modeling of the experimental profiles of simultaneous diffusion of B and Si under p-type extrinsic conditions revealed that both species are mediated by neutral and singly, positively charged Si self-interstitials. The diffusion of As and Si under extrinsic n-type conditions yielded a model consisting of the interstitialcy and vacancy mechanisms of diffusion via singly negatively charged self-interstitials and neutral vacancies. The simultaneous diffusion of P and Si has been modeled on the basis of neutral and singly negatively charged self-interstitials and neutral and singly positively charged P species. Additionally, the temperature dependence of the diffusion coefficient of Si in Ge was measured over the temperature range of 550 C to 900 C using a buried Si layer in an epitaxially grown Ge layer.

  19. Isotopic Evolution of Saline Lakes in the Low-Latitude and Polar Regions

    SciTech Connect (OSTI)

    Horita, Juske [ORNL

    2009-01-01

    Isotopic fractionations associated with two primary processes (evaporation and freezing of water) are discussed, which are responsible for the formation and evolution of saline lakes in deserts from both low-latitude and the Polar regions. In an evaporative system, atmospheric parameters (humidity and isotopic composition of water vapor) have strong influence on the isotopic behavior of saline lakes, and in a freezing system, salinity build-up largely controls the extent of freezing and associated isotope fractionation. In both systems, salinity has a direct impact on the isotopic evolution of saline lakes. It is proposed that a steady-state 'terminal lake' model with short-term hydrologic and environmental perturbations can serve as a useful framework for investigating both evaporative and freezing processes of perennial saline lakes. Through re-assessment of own work and literature data for saline lakes, it was demonstrated that effective uses of the isotope activity compositions of brines and salinity-chemistry data could reveal dynamic changes and evolution in the isotopic compositions of saline lakes in response to hydrologic and environmental changes. The residence time of isotopic water molecules in lakes determines the nature of responses in the isotopic compositions following perturbations in the water and isotope balances (e.g., dilution by inflow, water deficit by increased evaporation, and/or reduction in inflow). The isotopic profiles of some saline lakes from the Polar regions show that they switched the two contrasting modes of operation between evaporative and freezing systems, in response to climate and hydrological changes in the past.

  20. Stable isotope and groundwater flow dynamics of agricultural irrigation recharge into groundwater resources of the Central Valley, California

    SciTech Connect (OSTI)

    Davisson, M.L.; Criss, R.E.

    1995-01-01

    Intensive agricultural irrigation and overdraft of groundwater in the Central Valley of California profoundly affect the regional quality and availability of shallow groundwater resources. In the natural state, the {delta}{sup 18}O values of groundwater were relatively homogeneous (mostly -7.0 {+-} 0.5{per_thousand}), reflecting local meteoric recharge that slowly (1-3m/yr) flowed toward the valley axis. Today, on the west side of the valley, the isotope distribution is dominated by high {sup 18}O enclosures formed by recharge of evaporated irrigation waters, while the east side has bands of low {sup 18}O groundwater indicating induced recharge from rivers draining the Sierra Nevada mountains. Changes in {delta}{sup 18}O values caused by the agricultural recharge strongly correlate with elevated nitrate concentrations (5 to >100 mg/L) that form pervasive, non-point source pollutants. Small, west-side cities dependent solely on groundwater resources have experienced increases of >1.0 mg/L per year of nitrate for 10-30 years. The resultant high nitrates threaten the economical use of the groundwater for domestic purposes, and have forced some well shut-downs. Furthermore, since >80% of modern recharge is now derived from agricultural irrigation, and because modern recharge rates are {approximately}10 times those of the natural state, agricultural land retirement by urbanization will severely curtail the current safe-yields and promote overdraft pumping. Such overdrafting has occurred in the Sacramento metropolitan area for {approximately}40 years, creating cones of depression {approximately}25m deep. Today, groundwater withdrawal in Sacramento is approximately matched by infiltration of low {sup 18}O water (-11.0{per_thousand}) away from the Sacramento and American Rivers, which is estimated to occur at 100-300m/year from the sharp {sup 18}O gradients in our groundwater isotope map.

  1. If a fire should occur... CLOSE the doors to

    E-Print Network [OSTI]

    Al Faruque, Mohammad Abdullah

    If a fire should occur... · CLOSE the doors to stop the spread of the fire · SOUND the alarm, alert others to the danger · GET OUT of the building · NOTIFY the fire department DO NOT go back into the building or try to save your stuff. Clothes, books and papers can be replaced- YOU CAN'T! Living With Fire

  2. Improving Home Automation by Discovering Regularly Occurring Device Usage Patterns

    E-Print Network [OSTI]

    Holder, Lawrence B.

    Improving Home Automation by Discovering Regularly Occurring Device Usage Patterns Edwin O in an environment can be mined to discover significant patterns, which an intelligent agent could use to automate of two prediction algorithms, thus demonstrating multiple uses for a home automation system. Finally, we

  3. Quantum fluctuations and isotope effects in ab initio descriptions of water

    SciTech Connect (OSTI)

    Wang, Lu; Markland, Thomas E.; Ceriotti, Michele

    2014-09-14

    Isotope substitution is extensively used to investigate the microscopic behavior of hydrogen bonded systems such as liquid water. The changes in structure and stability of these systems upon isotope substitution arise entirely from the quantum mechanical nature of the nuclei. Here, we provide a fully ab initio determination of the isotope exchange free energy and fractionation ratio of hydrogen and deuterium in water treating exactly nuclear quantum effects and explicitly modeling the quantum nature of the electrons. This allows us to assess how quantum effects in water manifest as isotope effects, and unravel how the interplay between electronic exchange and correlation and nuclear quantum fluctuations determine the structure of the hydrogen bond in water.

  4. Isotope Specific Remediation Media and Systems - 13614

    SciTech Connect (OSTI)

    Denton, Mark S.; Mertz, Joshua L. [Kurion, Inc. Oak Ridge, Tennessee 37831 (United States)] [Kurion, Inc. Oak Ridge, Tennessee 37831 (United States); Morita, Keisuke [Japan Atomic Energy Agency, Tokai Research and Development Center, Fukushima Project Team, Tokai-mura, Ibaraki-ken, 319-1195 (Japan)] [Japan Atomic Energy Agency, Tokai Research and Development Center, Fukushima Project Team, Tokai-mura, Ibaraki-ken, 319-1195 (Japan)

    2013-07-01

    On March 11, 2011, now two years ago, the magnitude 9.0 Great East Japan earthquake, Tohoku, hit off the Fukushima coast of Japan. While, of course, most of the outcome of this unprecedented natural and manmade disaster was a negative, both in Japan and worldwide, there have been some extremely invaluable lessons learned and new emergency recovery technologies and systems developed. As always, the mother of invention is necessity. Among these developments has been the development and full-scale implementation of proven isotope specific media (ISMs) with the intent of surgically removing specific hazardous isotopes for the purpose of minimizing dose to workers and the environment. The first such ISMs to be deployed at the Fukushima site were those removing cesium (Cs-137) and iodine (I-129). Since deployment on June 17, 2011, along with treated cooling water recycle, some 70% of the curies in the building liquid wastes have been removed by the Kurion system alone. The current levels of cesium are now only 2% of the original levels. Such an unprecedented, 'external cooling system' not only allowed the eventual cold shut down of the reactors in mid-December, 2011, but has allowed workers to concentrate on the cleanup of other areas of the site. Water treatment will continue for quite some time due to continued leakage into the buildings and the eventual goal of cleaning up the reactors and fuel pools themselves. With the cesium removal now in routine operation, other isotopes of concern are likely to become priorities. One such isotope is that of strontium, and yttrium (Sr-90 and Y-90), which is still at original levels causing further dose issues as well as impediments to discharge of the treated waste waters. For over a year now, a new synthetic strontium specific media has been under development and testing both in our licensed facility in Oak Ridge, Tennessee, but also in confirmatory tests by the Japan Atomic Energy Agency (JAEA) in Japan for Tokyo Electric Power Company (TEPCO). The tests have proven quite successful, even in high salt conditions, and, with loading and dose calculations being completed, will be proposed to add to the existing cesium system. There is no doubt, as high gamma isotopes are removed, other recalcitrant isotopes such as this will require innovative removal media, systems and techniques. Also coming out of this international effort are other ISM media and systems that can be applied more broadly to both Commercial Nuclear Power Plants (NPPs) as well as in Department of Energy (DOE) applications. This cesium and strontium specific media has further been successfully tested in 2012 at a Magnox station in the UK. The resulting proposed mitigation systems for pond and vault cleanup look quite promising. An extremely unusual ISM for carbon 14 (C-14), nickel (Ni-63) and cesium (Cs-137) has been developed for Diablo Canyon NPP for dose reduction testing in their fuel pool. These media will be deployed in Submersible Media Filter (SMF) and Submersible Columns (SC) systems adapted to standard Tri-Nuclear{sup R} housings common in the U.S. and UK. External Vessel Systems (mini-Fukushima) have also been developed as a second mitigation system for D and D and outages. Finally, technetium (Tc- 99) specific media developed for the Waste Treatment Plant (WTP) recycle or condensate (secondary) waste streams (WM 2011) are being further perfected and tested for At-Tank Tc-99 removal, as well as At Tank Cs media. In addition to the on-going media development, systems for deploying such media have developed over the last year and are in laboratory- and full-scale testing. These systems include the fore mentioned Submersible Media Filters (SMF), Submersible Columns (SC) and external pilot- and full-scale, lead-lag, canister systems. This paper will include the media development and testing, as well as that of the deployment systems themselves. (authors)

  5. Chromium Isotope Fractionation During Reduction of Cr(VI) Under Saturated Flow Conditions

    SciTech Connect (OSTI)

    Jamieson-Hanes, Julia H.; Gibson, Blair D.; Lindsay, Matthew B.J.; Kim, Yeongkyoo; Ptacek, Carol J.; Blowes, David W.

    2012-10-25

    Chromium isotopes are potentially useful indicators of Cr(VI) reduction reactions in groundwater flow systems; however, the influence of transport on Cr isotope fractionation has not been fully examined. Laboratory batch and column experiments were conducted to evaluate isotopic fractionation of Cr during Cr(VI) reduction under both static and controlled flow conditions. Organic carbon was used to reduce Cr(VI) in simulated groundwater containing 20 mg L{sup -1} Cr(VI) in both batch and column experiments. Isotope measurements were performed on dissolved Cr on samples from the batch experiments, and on effluent and profile samples from the column experiment. Analysis of the residual solid-phase materials by scanning electron microscopy (SEM) and by X-ray absorption near edge structure (XANES) spectroscopy confirmed association of Cr(III) with organic carbon in the column solids. Decreases in dissolved Cr(VI) concentrations were coupled with increases in {delta}{sup 53}Cr, indicating that Cr isotope enrichment occurred during reduction of Cr(VI). The {delta}{sup 53}Cr data from the column experiment was fit by linear regression yielding a fractionation factor ({alpha}) of 0.9979, whereas the batch experiments exhibited Rayleigh-type isotope fractionation ({alpha} = 0.9965). The linear characteristic of the column {delta}{sup 53}Cr data may reflect the contribution of transport on Cr isotope fractionation.

  6. Isotope Tracer Studies of Diffusion in Sillicates and of Geological Transport Processes Using Actinide Elements

    SciTech Connect (OSTI)

    Wasserburg, Gerald J

    2008-07-31

    The objectives were directed toward understanding the transport of chemical species in nature, with particular emphasis on aqueous transport in solution, in colloids, and on particles. Major improvements in measuring ultra-low concentrations of rare elements were achieved. We focused on two areas of studies: (1) Field, laboratory, and theoretical studies of the transport and deposition of U, Th isotopes and their daughter products in natural systems; and (2) Study of calcium isotope fractionation effects in marine carbonates and in carbonates precipitated in the laboratory, under controlled temperature, pH, and rates of precipitation. A major study of isotopic fractionation of Ca during calcite growth from solution has been completed and published. It was found that the isotopic shifts widely reported in the literature and attributed to biological processes are in fact due to a small equilibrium fractionation factor that is suppressed by supersaturation of the solution. These effects were demonstrated in the laboratory and with consideration of the solution conditions in natural systems, where [Ca{sup 2+}] >> [CO{sub 3}{sup 2-}] + [HCO{sub 3}{sup -}]. The controlling rate is not the diffusion of Ca, as was earlier proposed, but rather the rate of supply of [CO{sub 3}{sup 2-}] ions to the interface. This now opens the issues of isotopic fractionation of many elements to a more physical-chemical approach. The isotopic composition of Ca {Delta}({sup 44}Ca/{sup 40}Ca) in calcite crystals has been determined relative to that in the parent solutions by TIMS using a double spike. Solutions were exposed to an atmosphere of NH{sub 3} and CO{sub 2}, provided by the decomposition of (NH4)2CO3. Alkalinity, pH, and concentrations of CO{sub 3}{sup 2-}, HCO{sub 3}{sup -}, and CO{sub 2} in solution were determined. The procedures permitted us to determine {Delta}({sup 44}Ca/{sup 40}Ca) over a range of pH conditions, with the associated ranges of alkalinity. Two solutions with greatly different Ca concentrations were used, but, in all cases, the condition [Ca] >> [CO{sub 3}{sup 2-}] was met. A wide range in {Delta}({sup 44}Ca/{sup 40}Ca) was found for the calcite crystals, extending from 0.04 {+-} 0.13 to -1.34 {+-} 0.15 {per_thousand}, generally anticorrelating with the amount of Ca removed from the solution. The results show that {Delta}({sup 44}Ca/{sup 40}Ca) is a linear function of the saturation state of the solution with respect to calcite ({Omega}). The two parameters are very well correlated over a wide range in {Omega} for each solution with a given [Ca]. Solutions, which were vigorously stirred, showed a much smaller range in {Delta}({sup 44}Ca/{sup 40}Ca) and gave values of -0.42 {+-} 0.14 {per_thousand}, with the largest effect at low {Omega}. It is concluded that the diffusive flow of CO{sub 3}{sup 2-} into the immediate neighborhood of the crystal-solution interface is the rate-controlling mechanism and that diffusive transport of Ca{sup 2+} is not a significant factor. The data are simply explained by the assumptions that: (a) the immediate interface of the crystal and the solution is at equilibrium with {Delta}({sup 44}Ca/{sup 40}Ca) {approx} -1.5 {+-} 0.25 {per_thousand}, and (b) diffusive inflow of CO{sub 3}{sup 2-} causes supersaturation, thus precipitating Ca from the regions, exterior to the narrow zone of equilibrium. We consider this model to be a plausible explanation of the available data reported in the literature. The well-resolved but small and regular isotope fractionation shifts in Ca are thus not related to the diffusion of very large hydrated Ca complexes, but rather due to the ready availability of Ca in the general neighborhood of the crystal solution interface. The largest isotopic shift which occurs is a small equilibrium effect which is then subdued by supersaturation precipitation for solutions where [Ca{sup 2+}] >> [CO{sub 3}{sup 2-}] + [HCO{sub 3}{sup -}]. It is shown that there is a clear temperature dependence of the net isotopic shifts, which is simply due to changes in {Omega}

  7. Online Catalog of Isotope Products from DOE's National Isotope Development Center

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The National Isotope Development Center (NIDC) interfaces with the User Community and manages the coordination of isotope production across the facilities and business operations involved in the production, sale, and distribution of isotopes. A virtual center, the NIDC is funded by the Isotope Development and Production for Research and Applications (IDPRA) subprogram of the Office of Nuclear Physics in the U.S. Department of Energy Office of Science. The Isotope subprogram supports the production, and the development of production techniques of radioactive and stable isotopes that are in short supply for research and applications. Isotopes are high-priority commodities of strategic importance for the Nation and are essential for energy, medical, and national security applications and for basic research; a goal of the program is to make critical isotopes more readily available to meet domestic U.S. needs. This subprogram is steward of the Isotope Production Facility (IPF) at Los Alamos National Laboratory (LANL), the Brookhaven Linear Isotope Producer (BLIP) facility at BNL, and hot cell facilities for processing isotopes at ORNL, BNL and LANL. The subprogram also coordinates and supports isotope production at a suite of university, national laboratory, and commercial accelerator and reactor facilities throughout the Nation to promote a reliable supply of domestic isotopes. The National Isotope Development Center (NIDC) at ORNL coordinates isotope production across the many facilities and manages the business operations of the sale and distribution of isotopes.

  8. Literature survey of isotopic abundance data for 1987-1989

    SciTech Connect (OSTI)

    Holden, N.E. (Brookhaven National Lab., Upton, NY (USA))

    1989-08-09

    I have compiled all of the data on isotopic abundance measurements and their variation in nature for the time period since the last General Assembly. Most of the data deals with the variations in the abundances as given by per mil deviations from some standard. As such, they are not of major interest to the Atomic Weights Commission. However, there were some measurements which are of general interest in this list.

  9. Isotope Development & Production | Nuclear Science | ORNL

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

    Separation & Processing Strategic Isotope Production Super Heavy Element Discovery Nuclear Security Science & Technology Nuclear Systems Modeling, Simulation & Validation...

  10. Radioactive Mineral Occurences in Nevada | 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 onRAPID/Geothermal/Exploration/Colorado <RAPID/Geothermal/Water Use/NevadaaToolsRadioactive Mineral Occurences in

  11. Isotope Cancer Treatment Research at LANL

    ScienceCinema (OSTI)

    Weidner, John; Nortier, Meiring

    2014-06-02

    Los Alamos National Laboratory has produced medical isotopes for diagnostic and imaging purposes for more than 30 years. Now LANL researchers have branched out into isotope cancer treatment studies. New results show that an accelerator-based approach can produce clinical trial quantities of actinium-225, an isotope that has promise as a way to kill tumors without damaging surrounding healthy cells.

  12. Advancement of isotope separation for the production of reference standards

    SciTech Connect (OSTI)

    Jared Horkley; Christopher McGrath; Andrew Edwards; Gaven Knighton; Kevin Carney; Jacob Davies; James Sommers; Jeffrey Giglio

    2012-03-01

    Idaho National Laboratory (INL) operates a mass separator that is currently producing high purity isotopes for use as internal standards for high precision isotope dilution mass spectrometry (IDMS). In 2008, INL began the revival of the vintage 1970’s era instrument. Advancements thus far include the successful upgrading and development of system components such as the vacuum system, power supplies, ion-producing components, and beam detection equipment. Progress has been made in the separation and collection of isotopic species including those of Ar, Kr, Xe, Sr, and Ba. Particular focuses on ion source improvements and developments have proven successful with demonstrated output beam currents of over 10 micro-amps 138Ba and 350nA 134Ba from a natural abundance source charge (approximately 2.4 percent 134Ba). In order to increase production and collection of relatively high quantities (mg levels) of pure isotopes, several advancements have been made in ion source designs, source material introduction, and beam detection and collection. These advancements and future developments will be presented.

  13. Do naked singularities generically occur in generalized theories of gravity?

    E-Print Network [OSTI]

    Kengo Maeda; Takashi Torii; Makoto Narita

    1998-10-27

    A new mechanism for causing naked singularities is found in an effective superstring theory. We investigate the gravitational collapse in a spherically symmetric Einstein-Maxwell-dilaton system in the presence of a pure cosmological constant "potential", where the system has no static black hole solution. We show that once gravitational collapse occurs in the system, naked singularities necessarily appear in the sense that the field equations break down in the domain of outer communications. This suggests that in generalized theories of gravity, the non-minimally coupled fields generically cause naked singularities in the process of gravitational collapse if the system has no static or stationary black hole solution.

  14. Evolution of the Namaqua-Natal Belt, southern Africa A geochronological and isotope geochemical review

    E-Print Network [OSTI]

    Patterson, William P.

    Evolution of the Namaqua-Natal Belt, southern Africa ­ A geochronological and isotope geochemical Available online 10 July 2006 Abstract Juvenile crust formation within the Namaqua-Natal Belt occurred of the Mesoproterozoic evolution of the Namaqua-Natal Belt. Graben formation with associated extrusion of lavas

  15. Isotopic Analysis of Uranium in NIST SRM Glass by Femtosecond Laser Ablation

    SciTech Connect (OSTI)

    Duffin, Andrew M.; Hart, Garret L.; Hanlen, Richard C.; Eiden, Gregory C.

    2013-05-19

    We employed femtosecond Laser Ablation Multicollector Inductively Coupled Mass Spectrometry for the 11 determination of uranium isotope ratios in a series of standard reference material glasses (NIST 610, 612, 614, and 12 616). This uranium concentration in this series of SRM glasses is a combination of isotopically natural uranium in 13 the materials used to make the glass matrix and isotopically depleted uranium added to increase the uranium 14 elemental concentration across the series. Results for NIST 610 are in excellent agreement with literature values. 15 However, other than atom percent 235U, little information is available for the remaining glasses. We present atom 16 percent and isotope ratios for 234U, 235U, 236U, and 238U for all four glasses. Our results show deviations from the 17 certificate values for the atom percent 235U, indicating the need for further examination of the uranium isotopes in 18 NIST 610-616. Our results are fully consistent with a two isotopic component mixing between the depleted 19 uranium spike and natural uranium in the bulk glass.

  16. Appraisal of transport and deformation in shale reservoirs using natural noble gas tracers

    SciTech Connect (OSTI)

    Heath, Jason E.; Kuhlman, Kristopher L.; Robinson, David G.; Bauer, Stephen J.; Gardner, William Payton

    2015-09-01

    This report presents efforts to develop the use of in situ naturally-occurring noble gas tracers to evaluate transport mechanisms and deformation in shale hydrocarbon reservoirs. Noble gases are promising as shale reservoir diagnostic tools due to their sensitivity of transport to: shale pore structure; phase partitioning between groundwater, liquid, and gaseous hydrocarbons; and deformation from hydraulic fracturing. Approximately 1.5-year time-series of wellhead fluid samples were collected from two hydraulically-fractured wells. The noble gas compositions and isotopes suggest a strong signature of atmospheric contribution to the noble gases that mix with deep, old reservoir fluids. Complex mixing and transport of fracturing fluid and reservoir fluids occurs during production. Real-time laboratory measurements were performed on triaxially-deforming shale samples to link deformation behavior, transport, and gas tracer signatures. Finally, we present improved methods for production forecasts that borrow statistical strength from production data of nearby wells to reduce uncertainty in the forecasts.

  17. Analysis of hydrogen isotope mixtures

    DOE Patents [OSTI]

    Villa-Aleman, Eliel (Aiken, SC)

    1994-01-01

    An apparatus and method for determining the concentrations of hydrogen isotopes in a sample. Hydrogen in the sample is separated from other elements using a filter selectively permeable to hydrogen. Then the hydrogen is condensed onto a cold finger or cryopump. The cold finger is rotated as pulsed laser energy vaporizes a portion of the condensed hydrogen, forming a packet of molecular hydrogen. The desorbed hydrogen is ionized and admitted into a mass spectrometer for analysis.

  18. Computer Study of Isotope Production in High Power Accelerators

    E-Print Network [OSTI]

    K. A. Van Riper; S. G. Mashnik; W. B. Wilson

    1999-01-25

    Methods for radionuclide production calculation in a high power proton accelerator have been developed and applied to study production of 22 isotopes by high-energy protons and neutrons. These methods are readily applicable to accelerator, and reactor, environments other than the particular model we considered and to the production of other radioactive and stable isotopes. We have also developed methods for evaluating cross sections from a wide variety of sources into a single cross section set and have produced an evaluated library covering about a third of all natural elements. These methods also are applicable to an expanded set of reactions. A 684 page detailed report on this study, with 37 tables and 264 color figures is available on the Web at http://t2.lanl.gov/publications/publications.html, or, if not accessible, in hard copy from the authors.

  19. Development of Halide and Oxy-Halides for Isotopic Separations

    SciTech Connect (OSTI)

    Leigh R. Martin; Aaron T. Johnson; Jana Pfeiffer; Martha R. Finck

    2014-10-01

    The goal of this project was to synthesize a volatile form of Np for introduction into mass spectrometers at INL. Volatile solids of the 5f elements are typically those of the halides (e.g. UF6), however fluorine is highly corrosive to the sensitive internal components of the mass separator, and the other volatile halides exist as several different stable isotopes in nature. However, iodide is both mono-isotopic and volatile, and as such presents an avenue for creation of a form of Np suitable for introduction into the mass separator. To accomplish this goal, the technical work in the project sought to establish a novel synthetic route for the conversion NpO2+ (dissolved in nitric acid) to NpI3 and NpI4.

  20. EIS-0249: Medical Isotopes Production Project

    Broader source: Energy.gov [DOE]

    This EIS evaluates the potential environmental impacts of a proposal to establish a production capability for molybdenum-99 (Mo-99) and related medical isotopes.

  1. Strategic Isotope Production | ornl.gov

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

    Testing facility (IMET) are routinely used in the production, purification, packaging, and shipping of a number of isotopes of national importance, including: 75Se, 63Ni,...

  2. Stable Isotope Protocols: Sampling and Sample Processing

    E-Print Network [OSTI]

    Levin, Lisa A; Currin, Carolyn

    2012-01-01

    plants, benthic microalgae [BMI], benthic macroalgae) andin a dessicator, prior to analysis. A.2 Benthic microalgaeBenthic microalgae (BMI) can be collected for isotope

  3. Integration of Nontraditional Isotopic Systems Into Reaction...

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

    Nontraditional Isotopic Systems Into Reaction-Transport Models of EGS For Exploration, Evaluation of Water-Rock Interaction, and Impacts of Water Chemistry on Reservoir...

  4. Application of the Isotope Ratio Method to a Boiling Water Reactor

    SciTech Connect (OSTI)

    Frank, Douglas P.; Gerlach, David C.; Gesh, Christopher J.; Hurley, David E.; Meriwether, George H.; Mitchell, Mark R.; Reid, Bruce D.

    2010-08-11

    The isotope ratio method is a technique for estimating the energy or plutonium production in a fission reactor by measuring isotope ratios in non-fuel reactor components. The isotope ratios in these components can then be directly related to the cumulative energy production with standard reactor modeling methods. All reactor materials contain trace elemental impurities at parts per million levels, and the isotopes of these elements are transmuted by neutron irradiation in a predictable manner. While measuring the change in a particular isotope’s concentration is possible, it is difficult to correlate to energy production because the initial concentration of that element may not be accurately known. However, if the ratio of two isotopes of the same element can be measured, the energy production can then be determined without knowing the absolute concentration of that impurity since the initial natural ratio is known. This is the fundamental principle underlying the isotope ratio method. Extremely sensitive mass-spectrometric methods are currently available that allow accurate measurements of the impurity isotope ratios in samples. Additionally, “indicator” elements with stable activation products have been identified so that their post-irradiation isotope ratios remain constant. This method has been successfully demonstrated on graphite-moderated reactors. Graphite reactors are particularly well-suited to such analyses since the graphite moderator is resident in the fueled region of the core for the entire period of operation. Applying this method to other reactor types is more difficult since the resident portions of the reactor available for sampling are either outside the fueled region of the core or structural components of individual fuel assemblies. The goal of this research is to show that the isotope ratio method can produce meaningful results for light water-moderated power reactors. In this work, we use the isotope ratio method to estimate the energy production in a boiling water reactor fuel bundle based on measurements taken from the corresponding fuel assembly channel. Our preliminary results are in good agreement with the actual operating history of the reactor during the cycle that the fuel bundle was resident in the core.

  5. A simplified method for obtaining high-purity perchlorate from groundwater for isotope analyses.

    SciTech Connect (OSTI)

    vonKiparski, G; Hillegonds, D

    2011-04-04

    Investigations into the occurrence and origin of perchlorate (ClO{sub 4}{sup -}) found in groundwater from across North America have been sparse until recent years, and there is mounting evidence that natural formation mechanisms are important. New opportunities for identifying groundwater perchlorate and its origin have arisen with the utilization of improved detection methods and sampling techniques. Additionally, application of the forensic potential of isotopic measurements has begun to elucidate sources, potential formation mechanisms and natural attenuation processes. Procedures developed appear to be amenable to enable high precision stable isotopic analyses, as well as lower precision AMS analyses of {sup 36}Cl. Immediate work is in analyzing perchlorate isotope standards and developing full analytical accuracy and uncertainty expectations. Field samples have also been collected, and will be analyzed when final qa/qc samples are deemed acceptable.

  6. Discovery of Isotopes of Elements with Z $\\ge$ 100

    E-Print Network [OSTI]

    M. Thoennessen

    2012-03-09

    Currently, 163 isotopes of elements with Z $\\ge$ 100 have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  7. Uranium isotopes fingerprint biotic reduction

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

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-04-20

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U),more »i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. In addition, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.« less

  8. Spatial periphery of lithium isotopes

    SciTech Connect (OSTI)

    Galanina, L. I., E-mail: galan_lidiya@mail.ru; Zelenskaja, N. S. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

    2013-12-15

    The spatial structure of lithium isotopes is studied with the aid of the charge-exchange and (t, p) reactions on lithium nuclei. It is shown that an excited isobaric-analog state of {sup 6}Li (0{sup +}, 3.56MeV) has a halo structure formed by a proton and a neutron, that, in the {sup 9}Li nucleus, there is virtually no neutron halo, and that {sup 11}Li is a Borromean nucleus formed by a {sup 9}Li core and a two-neutron halo manifesting itself in cigar-like and dineutron configurations.

  9. Uranium molecular laser isotope separation

    SciTech Connect (OSTI)

    Jensen, R.J.; Sullivan, A.

    1982-01-01

    The Molecular Laser Isotope Separation program is moving into the engineering phase, and it is possible to determine in some detail the plant cost terms involved in the process economics. A brief description of the MLIS process physics is given as a motivation to the engineering and economics discussion. Much of the plant cost arises from lasers and the overall optical system. In the paper, the authors discuss lasers as operating units and systems, along with temporal multiplexing and Raman shifting. Estimates of plant laser costs are given.

  10. Solvent dependence of the carbon kinetic isotope effect on the decarboxylation of 4-pyridylacetic acid. A model for enzymatic decarboxylations

    SciTech Connect (OSTI)

    Marlier, J.F.; O'Leary, M.H.

    1986-08-06

    Carbon kinetic isotope effects have been measured for the decarboxylation of 4-pyridylacetic acid in pure water and in water-dioxane mixtures at 25/sup 0/C. The isotope effects are k/sup 12//k/sup 13/ = 1.064 in 75% dioxane, 1.060 in 50% dioxane, 1.056 in 25% dioxane, and 1.057 in pure water. The decrease in kinetic isotope effect parallels a more dramatic 4000-fold decrease in the observed first-order rate constant on going from 75% dioxane to pure water. No solvent isotope effect is observed in 50% water/dioxane, and as expected, the carbon isotope effect is the same in 50% D/sub 2/O/dioxane as in 50% H/sub 2/O/dioxane. The reaction appears to occur in a single step, without appreciable proton movement. The variation in rate is attributed to variations in the degree of transition-state solvation with only very small changes in ground-state effects and in the degree of carbon-carbon bond breaking in the transition state. These results indicate that the magnitudes of isotope effects observed in model reactions in H/sub 2/O are an appropriate model for magnitudes of isotope effects in enzymatic decarboxylations.

  11. Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Farrar, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  12. Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Welhan, Et Al., 1988) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  13. BETA DECAY MEASUREMENTS OF NEUTRON DEFICIENT CESIUM ISOTOPES

    E-Print Network [OSTI]

    Parry, R.F.

    2010-01-01

    OF NEUTRON DEFICIENT CESIUM ISOTOPES by Roger Franklin Parryof Neutron Deficient Cesium Isotopes Table of ContentsReferences Wapstra xenon and cesium mass excess values 108

  14. Strontium Isotopes Test Long-Term Zonal Isolation of Injected...

    Office of Scientific and Technical Information (OSTI)

    Strontium Isotopes Test Long-Term Zonal Isolation of Injected and Marcellus Formation Water after Hydraulic Fracturing Citation Details In-Document Search Title: Strontium Isotopes...

  15. Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes...

    Office of Environmental Management (EM)

    Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Presentation from the 34th Tritium Focus Group...

  16. Advances in Hydrogen Isotope Separation Using Thermal Cycling...

    Office of Environmental Management (EM)

    Hydrogen Isotope Separation Using Thermal Cycling Absorption Process (TCAP) Advances in Hydrogen Isotope Separation Using Thermal Cycling Absorption Process (TCAP) Presentation...

  17. Hydrogen Isotope Research Center (HRC), University of Toyama...

    Office of Environmental Management (EM)

    Hydrogen Isotope Research Center (HRC), University of Toyama Hydrogen Isotope Research Center (HRC), University of Toyama Presentation from the 34th Tritium Focus Group Meeting...

  18. 2008 Workshop on The Nation's Needs for Isotopes: Present and...

    Office of Science (SC) Website

    and radioactive isotope products that are used worldwide. Hundreds of applications in medicine, industry, national security and research depend on isotopes as vital components. The...

  19. Permeation of Multiple Isotopes in the Transition Between Surface...

    Office of Environmental Management (EM)

    Permeation of Multiple Isotopes in the Transition Between Surface- and Diffusion-Limited Regimes Permeation of Multiple Isotopes in the Transition Between Surface- and...

  20. Isotopic Analysis At Central Nevada Seismic Zone Region (Kennedy...

    Open Energy Info (EERE)

    Isotopic Analysis At Central Nevada Seismic Zone Region (Kennedy & Van Soest, 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  1. [Carbon isotope fractionation inplants]. Final report

    SciTech Connect (OSTI)

    O`Leary, M.H.

    1990-12-31

    The objectives of this research are: To develop a theoretical and experimental framework for understanding isotope fractionations in plants; and to develop methods for using this isotope fractionation for understanding the dynamics of CO{sub 2} fixation in plants. Progress is described.

  2. The Quest for the Heaviest Uranium Isotope

    E-Print Network [OSTI]

    S. Schramm; D. Gridnev; D. V. Tarasov; V. N. Tarasov; W. Greiner

    2012-01-17

    We study Uranium isotopes and surrounding elements at very large neutron number excess. Relativistic mean field and Skyrme-type approaches with different parametrizations are used in the study. Most models show clear indications for isotopes that are stable with respect to neutron emission far beyond N=184 up to the range of around N=258.

  3. Efficient palladium isotope chromatograph for hydrogen (EPIC)

    SciTech Connect (OSTI)

    Embury, M.C.; Ellefson, R.E.; Melke, H.B. )

    1992-03-01

    The Efficient Palladium Isotope Chromatograph (EPIC) is a rapid cycling, computer-operated displacement chromatograph for the separation of hydrogen isotopes. EPIC incorporates several features that optimize product throughput and purity. This paper describes this palladium displacement chromatograph, the operations with protium and deuterium, and the design modifications for operation with tritium.

  4. Summer fire impacts and isotopic assessment of vegetation dynamics in Texas coastal Quercus virginiana communities 

    E-Print Network [OSTI]

    Hays, Kelley Ann

    1999-01-01

    and altered fire frequencies [] 200 years ago. The purpose of this study was to: (1) reconstruct plant community history in coastal Q. virginiana plant communities based on the natural abundance of isotopes in plants and soils, and (2) evaluate the potential...

  5. Experimental investigation of rates and mechanisms of isotope exchange (O, H) between volcanic ash and

    E-Print Network [OSTI]

    Bindeman, Ilya N.

    Experimental investigation of rates and mechanisms of isotope exchange (O, H) between volcanic ash-term exposure experi- ments of distal 7700 BP Mt. Mazama ash (À149& d2 H, +7& d18 O, 3.8 wt.% H2O and d2 H in native and reacted ash that can be used in defining the protocols for natural sample

  6. Applications of Sr Isotopes in Archaeology N.M. Slovak and A. Paytan

    E-Print Network [OSTI]

    Paytan, Adina

    an introduction to the fundamental principles, approaches, applications, and future directions of radiogenic stron of 86 Sr/88 Sr in natural N.M. Slovak (*) Department of Behavioral Sciences, Santa Rosa Junior College Sr/86 Sr signatures. M. Baskaran (ed.), Handbook of Environmental Isotope Geochemistry, Advances

  7. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01

    constructed to enrich liquid UF6 slightly as feed for thej) b. Optimum a. s: .X. UF6 feed, (kg per year) XBL 7912 -

  8. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01

    scale use of gas centrifuges for uranium is imminent, andUranium Enrichment (1978). United States Gas Centrifuge

  9. Isotopes

    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 CurrentHenryInhibitingInteractivePGAS andUniversityCancer therapy gets

  10. Isotope Geochemistry of Calcite Coatings and the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    B.D. Marshall; J.F. Whelan

    2000-07-27

    Calcite and opal coatings found on fracture footwalls and lithophysal cavity bottoms in the volcanic section at Yucca Mountain (exposed in a tunnel) contain a record of gradual chemical and isotopic changes that have occurred in the unsaturated zone. The thin (less than 6 cm) coatings are composed primarily of calcite, opal, chalcedony, and quartz. Fluid inclusions in calcite that homogenize at greater than ambient temperatures provide impetus for geochronologic studies in order to determine the thermal history. In the welded Topopah Spring Tuff (12.7 Ma), U-Pb ages of opal and chalcedony layers provide evidence of a long history of deposition throughout the past 10 m.y. However, these ages can constrain the ages of associated calcite layers only in samples with an easily interpretable microstratigraphy. Strontium isotope ratios in calcite increase with microstratigraphic position from the base up to the outermost surface of the coatings. The strontium incorporated in these coatings records the systematic change in pore-water isotopic composition due to water-rock interaction primarily in the overlying nonwelded tuffs. A one-dimensional advection-reaction model simulates strontium isotope ratios measured in pore water extracted from core in three vertical boreholes adjacent to the tunnel. By calculating the strontium isotope compositions of the rocks at various past times, the model predicts a history of the strontium isotope ratios in the water that matches the record in the calcite and therefore provides approximate ages. Oxygen isotope ratios measured in calcite gradually increase with decreasing model strontium age. Assuming that the oxygen isotope ratio of the percolating water was relatively constant, this trend indicates a gradual cooling of the rocks over millions of years, in agreement with thermal modeling of magma beneath the 12-Ma Timber Mountain caldera just north of Yucca Mountain. This model predicts that temperatures significantly exceeding current geotherm values occurred prior to 6 Ma. We find no evidence for Quaternary or recent thermal perturbations to the cooling rocks.

  11. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1985-11-08

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

  12. Impact of methane seeps on the local carbon-isotope record: a case study from a Late Jurassic hemipelagic section

    E-Print Network [OSTI]

    Gilli, Adrian

    Impact of methane seeps on the local carbon-isotope record: a case study from a Late Jurassic dis- sociation of methane hydrates, used to explain e.g. the Paleocene-Eocene Thermal Maximum (PETM excursions also occur in modern methane-bearing sedimentary succes- sions. These are caused when anae- robic

  13. Isotopic Studies of Contaminant Transport at the Hanford Site, WA

    E-Print Network [OSTI]

    Christensen, J.N.; Conrad, M.E.; DePaolo, D.J.; Dresel, P.E.

    2008-01-01

    1977. Subcommission on geochronology: Convention on the useby W. Sharp, Berkeley Geochronology Center). Isotopic

  14. Short course on St-02 applications of isotope dilutions and isotopic measurements

    SciTech Connect (OSTI)

    Miller, P.

    1998-01-05

    This short course includes information on these topics and subtopics: (I) Nuclear Properties: (A) Historic roots; (B) Nomenclature; (C) Nuclear Stability and abundance; (D) Uses of isotopic techniques; (II) Instrumentation: (A) Sources; (B) Mass resolving elements; (C) Detectors; (III) Making Isotopic Measurements by ICP-MS: (A) Deadtime Correction; (B) Mass Discrimination; (C) Signal /Noise considerations; (IV) Applications and examples: (A) Isotope dilution; (B) Double Spike; (C) Biological Application; (D) Environmental Application; (E) Geological.

  15. COMMENTS ON ANOMALOUS EFFECTS IN CHARGING OF PD POWDERS WITH HIGH DENSITY HYDROGEN ISOTOPES

    SciTech Connect (OSTI)

    Shanahan, K.

    2009-10-01

    In Kitamura, et al, Pd-containing materials are exposed to isotopes of hydrogen and anomalous results obtained. These are claimed to be a replication of another experiment conducted by Arata and Zhang. Erroneous basic assumptions are pointed out herein that alter the derived conclusions significantly. The final conclusion is that the reported results are likely normal chemistry combined with noise. Thus the claim to have proven that cold fusion is occurring in these systems is both premature and unlikely.

  16. Atomic-scale characterization of germanium isotopic multilayers by atom probe tomography

    SciTech Connect (OSTI)

    Shimizu, Y.; Takamizawa, H.; Toyama, T.; Inoue, K.; Nagai, Y. [Oarai Center, Institute for Materials Research, Tohoku University, 2145-2 Narita, Oarai, Ibaraki 311-1313 (Japan); Kawamura, Y.; Uematsu, M.; Itoh, K. M. [School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Haller, E. E. [University of California at Berkeley and Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2013-01-14

    We report comparison of the interfacial sharpness characterization of germanium (Ge) isotopic multilayers between laser-assisted atom probe tomography (APT) and secondary ion mass spectrometry (SIMS). An alternating stack of 8-nm-thick naturally available Ge layers and 8-nm-thick isotopically enriched {sup 70}Ge layers was prepared on a Ge(100) substrate by molecular beam epitaxy. The APT mass spectra consist of clearly resolved peaks of five stable Ge isotopes ({sup 70}Ge, {sup 72}Ge, {sup 73}Ge, {sup 74}Ge, and {sup 76}Ge). The degree of intermixing at the interfaces between adjacent layers was determined by APT to be around 0.8 {+-} 0.1 nm which was much sharper than that obtained by SIMS.

  17. 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

  18. Neutron Deficient Isotopes of Rhodium and Palladium

    E-Print Network [OSTI]

    Perlman, I.

    2010-01-01

    S OF RHODI U! \\~ AFD PALLADIUM by Manfred Lindner and I.Isotopes of B." odinm. and Palladium Hanfred Lindner and 1.i.a ABSTRACT A palladium activit;)r assigned to mass

  19. Atomic vapor laser isotope separation process

    DOE Patents [OSTI]

    Wyeth, R.W.; Paisner, J.A.; Story, T.

    1990-08-21

    A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

  20. A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER

    E-Print Network [OSTI]

    O'Donnell, Tom

    A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER FOR PRODUCTION OF NEUTRON-RICH NUCLEI ( 136 Xe Superconducting Cyclotron Laboratory's weekly \\Green Sheet," 30 July 1999 #12; c Thomas W. O'Donnell 2000 All

  1. Photodisintegration of the isotope {sup 116}Cd

    SciTech Connect (OSTI)

    Belyshev, S. S.; Ishkhanov, B. S. [Moscow State University (Russian Federation)] [Moscow State University (Russian Federation); Orlin, V. N.; Stopani, K. A.; Khankin, V. V.; Shvedunov, N. V., E-mail: gg.swedn@gmail.com [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

    2013-08-15

    The results obtained by measuring the yields of photodisintegration of the isotope {sup 116}Cd irradiated with bremsstrahlung photons whose spectrum had an endpoint energy of 55 MeV are presented and compared with the results of theoretical calculations.

  2. The Isotopic Abundances of Magnesium in Stars

    E-Print Network [OSTI]

    Pamela Gay; David L. Lambert

    1999-11-11

    Isotopic abundance ratios 24^Mg:25^Mg:26^Mg are derived for 20 stars from high- resolution spectra of the MgH A-X 0-0 band at 5140AA. With the exception of the weak g-band giant HR 1299, the stars are dwarfs that sample the metallicity range -1.8 < [Fe/H] <0.0. The abundance of 25^Mg amd 26^Mg relative to the dominant isotope 24^Mg decreases with decreasing [Fe/H] in fair accord with predictions from a recent model of galactic chemical evolution in which the Mg isotopes are synthesised by massive stars. Several stars appear especially enriched in the heavier Mg isotopes suggesting contamination by material from the envelopes of intermediate-mass AGB stars.

  3. GEOL 715: STABLE ISOTOPE GEOCHEMISTRY (Spring, 2015)

    E-Print Network [OSTI]

    , nomenclature, standards -kinetic and equilibrium fractionation processes -mass and isotope budgets -Rayleigh in terrestrial plants and plankton -applications: carbon budgets, tracking anthropogenic CO2, carbon export rates sources, trophic levels, terrestrial vs marine sources 3. Recent advances: -mass independent fractionation

  4. Utilization of Kinetic Isotope Effects for the Concentration of Tritium

    SciTech Connect (OSTI)

    Brown, Gilbert M.; Meyer, Thomas J.; Moyer, Bruce A.

    2000-06-01

    Work is in progress to develop methods for concentrating tritium in water based on large primary isotope effects in catalytic redox processes. Basic research is being conducted to develop the chemistry of a complete cyclic process. The process will remove tritium from H2O by concentrating it with respect to protio-water. This research involves developing chemical cycles that produce high concentration factors for HTO based on the discrimination of CH and C-T bonds in oxidation reactions. Several steps are required in a cyclic process for the concentration of tritium in water. In the first step, the tritium is incorporated in an organic compound. H-T discrimination occurs as the tritium containing compound is oxidized in a step involving a Ru(IV) oxo complex. Strong primary kinetic isotope effects lead to the oxidation of C-H bonds in preference to C-T bonds, and this reaction leads to concentration of tritium in the organic compound. The reduced form of the ruthenium compound can be reoxidized so that the oxidation step can be made catalytic.

  5. Immunology of naturally transmissible tumours

    E-Print Network [OSTI]

    Siddle, Hannah V.; Kaufman, Jim

    2014-09-04

    understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, Canine Transmissible Venereal Tumour (CTVT) that spreads among dogs and Devil Facial Tumour Disease (DFTD) among...

  6. The Giant Monopole Resonance in Pb isotopes

    E-Print Network [OSTI]

    Elias Khan

    2009-07-20

    The extraction of the nuclear incompressibility from the isoscalar giant monopole resonance (GMR) measurements is analysed. Both pairing and mutually enhanced magicity (MEM) effects play a role in the shift of the GMR energy between the doubly closed shell $^{208}$Pb nucleus and other Pb isotopes. Pairing effects are microscopically predicted whereas the MEM effect is phenomenologically evaluated. Accurate measurements of the GMR in open-shell Pb isotopes are called for.

  7. Water Research 37 (2003) 10151022 Heterogeneity of natural organic matter from the Chena River,

    E-Print Network [OSTI]

    Guo, Laodong

    2003-01-01

    continuous flow isotope ratio mass spectrometry and pyrolysis-gas chromatography/mass spectrometry (Py rights reserved. Keywords: Natural organic matter; Colloid; Stable isotope; Size fractionation; Pyrolysis that northern ecosystems have accumulated 25­33% of the world's soil carbon [8]. Carbon currently sequestered

  8. Intruder states in odd-mass Ag isotopes

    SciTech Connect (OSTI)

    Rogowski, J.; Alstad, J.; Brant, S.; Daniels, W.R.; De Frenne, D.; Heyde, K.; Jacobs, E.; Kaffrell, N.; Paar, V.; Skarnemark, G.; Trautmann, N. (Institut fuer Kernchemie, Universitaet Mainz, D-6500 Mainz (Federal Republic of Germany) Department of Chemistry, University of Oslo, N-0315 Oslo (Norway) Prirodoslovno-matematicki fakultet, University of Zagreb, 41000 Zagreb (Yugoslavia) Los Alamos National Laboratory, Los Alamos, NM (USA) Laboratorium voor Kernfysica, Proeftuinstraat 86, B-9000 Gent (Belgium) Department of Nuclear Chemistry, Chalmers University of Technology, S-41296 Goeteborg (Sweden))

    1990-12-01

    The information on the coexistence of deformed intruder states and normal spherical hole-core coupled states in odd-mass Ag nuclei has been extended to the neutron-rich isotopes {sup 113}Ag{sub 66} and {sup 115}Ag{sub 68}. Data have been obtained from an investigation of the {gamma} rays following the {beta}{sup {minus}} decay of the {sup 113,115}Pd precursors. A minimum for the excitation energy of the intruder states occurs in {sup 113}Ag{sub 66}, exactly at neutron midshell. The properties of the intruder states in {sup 109,111,113,115}Ag are discussed and a description in the framework of the interacting-boson-fermion model is presented.

  9. In-Situ Sampling and Characterization of Naturally Occuring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank; Guerin, Gilles; Goldberg, David

    2003-12-31

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Leg 204 scientific party members presented preliminary results and operational outcomes of ODP Leg 204 at the American Geophysical Union Fall meeting, which was held in San Francisco, CA; and, (2) a report was prepared by Dr. Gilles Guerin and David Goldberg from Lamont-Doherty Earth Observatory of Columbia University on their postcruise evaluation of the data, tools and measurement systems that were used for vertical seismic profiling (VSP) experiments during ODP Leg 204. The VSP report is provided herein. Intermediate in scale and resolution between the borehole data and the 3-D seismic surveys, the Vertical Seismic Profiles (VSP) carried during Leg 204 were aimed at defining the gas hydrate distribution on hydrate ridge, and refining the signature of gas hydrate in the seismic data. VSP surveys were attempted at five sites, following completion of the conventional logging operations. Bad hole conditions and operational difficulties did not allow to record any data in hole 1245E, but vertical and constant offset VSP were successful in holes 1244E, 1247B and 1250F, and walk-away VSP were successfully completed in holes 1244E, 1250F and 1251H. Three different tools were used for these surveys. The vertical VSP provided the opportunity to calculate interval velocity that could be compared and validated with the sonic logs in the same wells. The interval velocity profiles in Holes 1244E and 1247B are in very good agreement with the sonic logs. Information about the Leg 204 presentations at the AGU meeting are included in a separate Topical Report, which has been provided to DOE/NETL in addition to this Quarterly Report. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

  10. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Frank Rack

    2001-12-31

    The primary accomplishments during the first quarter were to mobilize materials and supplies to meet the deployment schedule for equipment and activities, as proposed under the DOE/NETL cooperative agreement with JOI, with initial testing and use of specialized tools and equipment on Ocean Drilling Program (ODP) Leg 201. As a requirement of the award, two copies of a technical feasibility report entitled ''Preliminary Evaluation of Existing Pressure/Temperature Coring Systems'' were delivered to DOE/NETL on October 22, 2001. The report was written to provide a discussion of the availability and compatibility of the four existing pressure coring devices in existence. Most of these systems are available for use by JOI/ODP aboard the D/V JOIDES Resolution, via purchase, lease, modification, etc. and the proposed capabilities to upgrade existing devices or systems for use on other platforms. In addition, the report provided a discussion of the compatibility of each existing coring device in conjunction with the use of the other coring devices, such as the advanced piston coring (APC) system used by ODP. Based on an evaluation of the JOI report, the DOE/NETL Program Manager William Gwilliam provided a ''Go'' decision to JOI for the further development of the ODP Pressure Coring System (PCS) and PCS Gas Manifold. During the reporting period negotiations were conducted with various potential subcontractors and vendors to establish the specific cost-sharing arrangements and work breakdown necessary to definitize the terms of the DOE/NETL cooperative agreement with JOI. The discussions were communicated with the DOE/NETL Program Manager, William Gwilliam, to keep NETL closely informed about events as this project evolved. A series of meetings were also held with ODP engineers, technical staff, and to plan for the implementation of the various tasks outlined in the JOI proposal to DOE for deployment during ODP Legs 201 and 204. These meetings helped to answer numerous unresolved questions and establish a firm timetable of remaining activities that needed to be accomplished by January 28, 2002, when ODP Leg 201 will begin.

  11. IN-SITU SAMPLING AND CHARACTERIZATION OF NATURALLY OCCURRING MARINE METHANE HYDRATE USING THE D/V JOIDES RESOLUTION

    SciTech Connect (OSTI)

    Frank R. Rack; Tim Francis; Peter Schultheiss; Philip E. Long; Barry M. Freifeld

    2005-04-01

    The primary activities accomplished during this quarter were continued efforts to develop plans for Phase 2 of this cooperative agreement based on the evolving operational planning for IODP Expedition 311, which will use the JOIDES Resolution to study marine methane hydrates along the Cascadia margin, offshore Vancouver Island. IODP Expedition 311 has been designed to further constrain the models for the formation of marine gas hydrate in subduction zone accretionary prisms. The objectives include characterizing the deep origin of the methane, its upward transport, its incorporation in gas hydrate, and its subsequent loss to the seafloor. The main attention of this expedition is on the widespread seafloor-parallel layer of dispersed gas hydrate located just above the base of the predicted stability field. In a gas hydrate formation model, methane is carried upward through regional sediment or small-scale fracture permeability, driven by the tectonic consolidation of the accretionary prism. The upward moving methane is incorporated into the gas hydrate clathrate as it enters the methane hydrate stability zone. Also important is the focusing of a portion of the upward methane flux into localized plumes or channels to form concentrations of near-seafloor gas hydrate. The amount of gas hydrate in local concentrations near the seafloor is especially important for understanding the response of marine gas hydrate to climate change. The expedition includes coring and downhole measurements at five sites across the Northern Cascadia accretionary prism. The sites will track the history of methane in an accretionary prism from (1) its production by mainly microbiological processes over a thick sediment vertical extent, (2) its upward transport through regional or locally focused fluid flow, (3) its incorporation in the regional hydrate layer above the BSR or in local concentrations at or near the seafloor, (4) methane loss from the hydrate by upward diffusion, and (5) methane oxidation and incorporation in seafloor carbonate, or expulsion to the ocean. This expedition builds on the previous Cascadia gas hydrate drilling of ODP Leg 146 and on more recent ODP Leg 204 off Oregon. Important experiments being considered for DOE/NETL funding as part of the JOI cooperative agreement include, (1) Logging-While-Drilling/Measurements-While-Drilling (LWD/MWD), (2) Pressure Core Sampling (PCS/HYACINTH) of gas hydrate, and fluid recovery under in situ conditions, (3) X-ray CT logging of whole cores under in situ conditions, and (4) Infrared thermal imaging of whole round cores to map temperature variations resulting from the presence of hydrate. Preliminary budget estimates have been made for each of these tasks and discussions are ongoing with DOE/NETL program managers to develop a final plan that can be implemented within the constraints of the available funding and logistical considerations.

  12. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank; Storms, Michael; Schroeder, Derryl; Dugan, Brandon; Schultheiss, Peter

    2002-12-31

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were (1) the preliminary postcruise evaluation of the tools and measurement systems that were used during ODP Leg 204 to study hydrate deposits on Hydrate Ridge, offshore Oregon from July through September 2002; and (2) the preliminary study of the hydrate-bearing core samples preserved in pressure vessels and in liquid nitrogen cryofreezers, which are now stored at the ODP Gulf Coast Repository in College Station, TX. During ODP Leg 204, several newly modified downhole tools were deployed to better characterize the subsurface lithologies and environments hosting microbial populations and gas hydrates. A preliminary review of the use of these tools is provided herein. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were used extensively and successfully during ODP Leg 204 aboard the D/V JOIDES Resolution. These systems provided a strong operational capability for characterizing the in situ properties of methane hydrates in subsurface environments on Hydrate Ridge during ODP Leg 204. Pressure was also measured during a trial run of the Fugro piezoprobe, which operates on similar principles as the DVTP-P. The final report describing the deployments of the Fugro Piezoprobe is provided in Appendix A of this report. A preliminary analysis and comparison between the piezoprobe and DVTP-P tools is provided in Appendix B of this report. Finally, a series of additional holes were cored at the crest of Hydrate Ridge (Site 1249) specifically geared toward the rapid recovery and preservation of hydrate samples as part of a hydrate geriatric study partially funded by the Department of Energy (DOE). In addition, the preliminary results from gamma density non-invasive imaging of the cores preserved in pressure vessels are provided in Appendix C of this report. An initial visual inspection of the samples stored in liquid nitrogen is provided in Appendix D of this report.

  13. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank; Schroeder, Derryl; Storms, Michael

    2001-03-31

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were the deployment of tools and measurement systems for testing on ODP Leg 201, which is intended to study hydrate deposits on the Peru margin as part of other scientific investigations. Additional accomplishments were related to the continuing evolution of tools and measurements systems in preparation for deployment on ODP Leg 204, Hydrate Ridge, offshore Oregon in July 2002. The design for PCS Gas Manifold was finalized and parts were procured to assemble the gas manifold and deploy this system with the Pressure Core Sampler (PCS) tool on ODP Leg 201. The PCS was deployed 17 times during ODP Leg 201 and successfully retrieved cores from a broad range of lithologies and sediment depths along the Peru margin. Eleven deployments were entirely successful, collecting between 0.5 and 1.0 meters of sediment at greater than 75% of hydrostatic pressure. The PCS gas manifold was used in conjunction with the Pressure Core Sampler (PCS) throughout ODP Leg 201 to measure the total volume and composition of gases recovered in sediment cores associated with methane hydrates. The results of these deployments will be the subject of a future progress report. The FUGRO Pressure Corer (FPC), one of the HYACE/HYACINTH pressure coring tools, and two FUGRO engineers were deployed on the D/V JOIDES Resolution during ODP Legs 201 to field-test this coring system at sites located offshore Peru. The HYACINTH project is a European Union (EU) funded effort to develop tools to characterize methane hydrate and measure physical properties under in-situ conditions. The field-testing of these tools provides a corollary benefit to DOE/NETL at no cost to this project. The opportunity to test these tools on the D/V JOIDES Resolution was negotiated as part of a cooperative agreement between JOI/ODP and the HYACINTH partners. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were deployed onboard the R/V JOIDES Resolution and used extensively during ODP Leg 201. Preliminary results indicate successful deployments of these tools. An infrared-thermal imaging system (IR-TIS) was delivered to JOI/ODP for testing and use on ODP Leg 201 to identify methane hydrate intervals in the recovered cores. The results of these experiments will be the subject of a future progress report. This report presents an overview of the primary methods used for deploying the ODP memory tools and PCS on ODP Leg 201 and the preliminary operational results of this leg. Discussions regarding the laboratory analysis of the recovered cores and downhole measurements made during these deployments will be covered in a future progress report.

  14. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank; Schultheiss, Peter

    2005-12-31

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were the implementation of a scientific ocean drilling expedition to study marine methane hydrates along the Cascadia margin, in the NE Pacific as part of Integrated Ocean Drilling Program (IODP) Expedition 311 using the R/V JOIDES Resolution and the deployment of all required equipment and personnel to provide the required services during this expedition. IODP Expedition 311 shipboard activities on the JOIDES Resolution began on August 28 and were concluded on October 28, 2005. New ODP Pressure Coring System (PCS) aluminum autoclave chambers were fabricated prior to the expedition. During the expedition, 16 PCS autoclaves containing pressure cores were X-rayed before and after depressurization using a modified Geotek MSCL-P (multi-sensor core logger-pressure) system. These PCS cores were density scanned using the MSCL-V (multi-sensor core logger-vertical) during depressurization to monitor gas evolution. The MSCL-V was set up in a 20-foot-long refrigerated container provided by Texas A&M University through the JOI contract with TAMRF. IODP Expedition 311 was the first time that PCS cores were examined before (using X-ray), during (using MSCL-V gamma density) and after (using X-ray) degassing to determine the actual volume and distribution of sediment and gas hydrate in the pressurized core, which will be important for more accurate determination of mass balances between sediment, gas, gas hydrate, and fluids in the samples collected. Geotek, Ltd was awarded a contract by JOI to provide equipment and personnel to perform pressure coring and related work on IODP Expedition 311 (Cascadia Margin Gas Hydrates). Geotek, Ltd. provided an automated track for use with JOI's infrared camera systems. Four auxiliary monitors showed infrared core images in real time to aid hydrate identification and sampling. Images were collected from 185 cores during the expedition and processed to provide continuous core temperature data. The HYACINTH pressure coring tools, subsystems, and core logging systems were mobilized to Astoria, Oregon. Both HYACINTH pressure coring tools, the HRC (HYACE Rotary Corer) and the FPC (Fugro Pressure Corer) were mobilized and used during the expedition. Two HYACINTH engineers supervised the use of the tools and five good pressure cores were obtained. Velocity, density and X-ray linear scanning data were collected from these cores at near in situ pressure using the MSCL-P system. Dr. Barry Freifeld from Lawrence Berkeley National Laboratory provided an X-ray source and detector for X-ray imaging of pressure cores and helped Geotek with the design and mobilization of the MSCL-P system. Pressure core handling, transfer, and logging was performed in a refrigerated 20-foot container supplied by Geotek, Ltd. After scanning, the pressure cores were stored for on-shore analysis in aluminum barrels. Additional studies were conducted at the Pacific Geoscience Center (PGC), where a shore based laboratory was established after Expedition 311.

  15. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Frank Rack

    2005-06-30

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were to refine budgets and operational plans for Phase 2 of this cooperative agreement based on the scheduling of a scientific ocean drilling expedition to study marine methane hydrates along the Cascadia margin, in the NE Pacific as part of the Integrated Ocean Drilling Program (IODP) using the R/V JOIDES Resolution. The proposed statement of work for Phase 2 will include three primary tasks: (1) research management oversight, provided by JOI; (2) mobilization, deployment and demobilization of pressure coring and core logging systems, through a subcontract with Geotek Ltd., who will work with Fugro and Lawrence Berkeley National Laboratory to accomplish some of the subtasks; and, (3) mobilization, deployment and demobilization of a refrigerated container van that will be used for degassing of the Pressure Core Sampler and density logging of these pressure cores, through a subcontract with the Texas A&M Research Foundation (TAMRF). More details about these tasks are provided in the following sections of this report. The appendices to this report contain a copy of the scientific prospectus for the upcoming IODP Expedition 311 (Cascadia Margin Hydrates), which provides details of operational and scientific planning for this expedition.

  16. IN-SITU SAMPLING AND CHARACTERIZATION OF NATURALLY OCCURRING MARINE METHANE HYDRATE USING THE D/V JOIDES RESOLUTION

    SciTech Connect (OSTI)

    Frank R. Rack; Peter Schultheiss; Melanie Holland

    2005-01-01

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) follow-up logging of pressure cores containing hydrate-bearing sediment; and (2) opening of some of these cores to establish ground-truth understanding. The follow-up measurements made on pressure cores in storage are part of a hydrate geriatric study related to ODP Leg 204. These activities are described in detail in Appendices A and B of this report. Work also continued on developing plans for Phase 2 of this cooperative agreement based on evolving plans to schedule a scientific ocean drilling expedition to study marine methane hydrates along the Cascadia margin, in the NE Pacific as part of the Integrated Ocean Drilling Program (IODP) using the R/V JOIDES Resolution.

  17. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank R

    2004-09-30

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

  18. IN-SITU SAMPLING AND CHARACTERIZATION OF NATURALLY OCCURRING MARINE METHANE HYDRATE USING THE D/V JOIDES RESOLUTION

    SciTech Connect (OSTI)

    Frank R. Rack

    2004-05-01

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Frank Rack presented preliminary results and operational outcomes of ODP Leg 204 at the DOE/NETL project review and two made two presentations at the ChevronTexaco Gulf of Mexico Hydrate JIP meeting, which were both held in Westminster, CO; and, (2) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

  19. In-Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D/V JOIDES Resolution

    SciTech Connect (OSTI)

    Rack, Frank

    2004-06-30

    The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) post-cruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.

  20. responses to environmental changes that are significantly more abrupt than those that would occur in nature. A

    E-Print Network [OSTI]

    Kaspari, Mike

    to a different growth chamber after every five weeks, and the appropriate [CO2] was re-set. Plants were watered weeks. At harvest, soil was collected using a 10-cm diameter corer. This soil core was then used to trap colonization26 . The total length of fungal hyphae was determined after extraction from a subsample of soil

  1. Structure and mechanical properties of naturally occurring lightweight foam-filled cylinder The peacock's tail coverts shaft and its

    E-Print Network [OSTI]

    Meyers, Marc A.

    ­ The peacock's tail coverts shaft and its components Z.Q. Liu a, , D. Jiao a , M.A. Meyers b , Z.F. Zhang a Available online 4 February 2015 Keywords: Biological materials Feather shaft Hierarchical structure Buckling Mechanical properties a b s t r a c t Feather shaft, which is primarily featured by a cylinder

  2. Simple Quantitative PCR Approach to Reveal Naturally Occurring and Mutation-Induced Repetitive Sequence Variation on the Drosophila Y Chromosome 

    E-Print Network [OSTI]

    Aldrich, John C.; Maggert, Keith A.

    2014-10-06

    pair product of qPCR. The absence of unique primer binding sites in blocks of short (e.g., pentameric or heptameric) satellites makes avoidance of primer-primer annealing the chief difficulty. An assay that circumvented this problem and allowed... to quantify their relative copy number. The reaction used primers with designed self-incompat- ibilities to disfavor primer-dimer formation and instead heavily- favor template-dependent and product-dependent priming. The products of template...

  3. Received 20 Feb 2014 | Accepted 27 May 2014 | Published 24 Jun 2014 Naturally occurring tumours in the basal

    E-Print Network [OSTI]

    cesta 54, HR-10000 Zagreb, Croatia. 3 Catholic University of Croatia, Ilica 242, HR-10000 Zagreb, Croatia. 4 Zoological Institute of Russian Academy of Sciences, Universitetskaya emb. 1, 199034 St

  4. Bulk chemical and Hfâ??W isotopic consequences of incomplete accretion during planet formation

    E-Print Network [OSTI]

    Dwyer, Christina A; Nimmo, Francis; Chambers, John E

    2015-01-01

    Bulk chemical and Hf–W isotopic consequences of incompletestyle affects the bulk chemical and isotopic outcomes ofto investigate the bulk chemical and isotopic consequences

  5. COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE

    E-Print Network [OSTI]

    Claeys, Philippe

    COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE of petrography and lead isotopes within pottery provenance study. KEYWORDS: LEAD ISOTOPES, THIN SECTION, SHERD

  6. TRIFID (TRansuranic Isotopic Fraction Interrogation Device): A second generation plutonium isotopic analysis system

    SciTech Connect (OSTI)

    Fleissner, J G; Coressel, T W; Freier, D A; Macklin, L L

    1989-01-01

    The TRIFID (Transuranic Isotopic Fraction Interrogation Device) system is a second generation plutonium isotopic analysis system which incorporates many new and unique features in the area of isotopic data acquisition and isotopic analysis instrument consisting of a Canberra Series 95-MCA interfaced to a Compaq 386 computer. The entire TRIFID software package, including MCA communications and isotopic analysis routines, was developed using the C programming language. Extensive use has been made of user friendly screens and menus for ease of operation and training and to facilitate use by technical level operators. Automated TRIFID features provide for MCA/ADC setup and acquisition, spectral storage, isotopic analysis, and report generation. One unique feature of the TRIFID system design allows it to be pre-programed for an entire day's counting. The isotopic analysis module (EPICS) contains an expert system formalism which is used to detect and assay for spectral interferences, and to automatically adjust peak fitting constraints based on spectral intensity variations. A TRIFID system has been in operation in a production laboratory at the Rocky Flats Plant since September 1988. Marked decreases in training and hands-on operation time have been achieved in comparison to the older, preceding isotopic systems. 2 refs., 3 figs.

  7. Resolving the stellar sources of isotopically rare presolar silicate grains through Mg and Fe isotopic analyses

    SciTech Connect (OSTI)

    Nguyen, Ann N.; Messenger, Scott, E-mail: lan-anh.n.nguyen@nasa.gov [Robert M. Walker Laboratory for Space Science, Astromaterials Research and Exploration Science Directorate, NASA Johnson Space Center, Houston, TX 77058 (United States)

    2014-04-01

    We conducted multi-element isotopic analyses of 11 presolar silicate grains from the Acfer 094 meteorite having unusual O isotopic compositions. Eight grains are {sup 18}O-rich, one is {sup 16}O-rich, and two are extremely {sup 17}O-rich. We constrained the grains' stellar sources by measuring their Si and Mg isotopic ratios, and also the {sup 54}Fe/{sup 56}Fe and {sup 57}Fe/{sup 56}Fe ratios for five grains. The Mg and Fe isotopic measurements were conducted after surrounding matrix grains were removed for more accurate ratios. Most of the {sup 18}O-rich silicates had anomalous Mg isotopic ratios, and their combined isotopic constraints are consistent with origins in low-mass Type II supernovae (SNe II) rather than high-metallicity stars. The isotopic ratios of the {sup 16}O-rich silicate are also consistent with an SN origin. Mixing small amounts of interior stellar material with the stellar envelope replicated all measured isotopic ratios except for {sup 29}Si/{sup 28}Si and {sup 54}Fe/{sup 56}Fe in some grains. The {sup 29}Si/{sup 28}Si ratios of all SN-derived grains are matched by doubling the {sup 29}Si yield in the Ne- and Si-burning zones. The {sup 54}Fe/{sup 56}Fe ratios of the grains imply elemental fractionation in the Si/S zone, or introduction of isotopically solar Fe by secondary processing. The two highly {sup 17}O-rich silicates exhibited significant {sup 25}Mg and/or {sup 26}Mg enrichments and their isotopic ratios are best explained by strong dilution of 1.15 M {sub ?} CO nova matter. We estimate that ?12% and 1% of presolar silicates have SN and nova origins, respectively, similar to presolar SiC and oxides. This implies that asymptotic giant branch stars are the dominant dust producers in the galaxy.

  8. Laboratory and numerical investigation of transport processes occurring above and within a saltwater wedge

    E-Print Network [OSTI]

    Clement, Prabhakar

    Laboratory and numerical investigation of transport processes occurring above and within knowledge, so far no one has completed laboratory experiments to study contaminant transport processes occurring within a saltwater wedge. In this study, we completed laboratory experiments to understand

  9. Laser Isotope Separation Employing Condensation Repression

    SciTech Connect (OSTI)

    Eerkens, Jeff W.; Miller, William H.

    2004-09-15

    Molecular laser isotope separation (MLIS) techniques using condensation repression (CR) harvesting are reviewed and compared with atomic vapor laser isotope separation (AVLIS), gaseous diffusion (DIF), ultracentrifuges (UCF), and electromagnetic separations (EMS). Two different CR-MLIS or CRISLA (Condensation Repression Isotope Separation by Laser Activation) approaches have been under investigation at the University of Missouri (MU), one involving supersonic super-cooled free jets and dimer formation, and the other subsonic cold-wall condensation. Both employ mixtures of an isotopomer (e.g. {sup i}QF{sub 6}) and a carrier gas, operated at low temperatures and pressures. Present theories of VT relaxation, dimerization, and condensation are found to be unsatisfactory to explain/predict experimental CRISLA results. They were replaced by fundamentally new models that allow ab-initio calculation of isotope enrichments and predictions of condensation parameters for laser-excited and non-excited vapors which are in good agreement with experiment. Because of supersonic speeds, throughputs for free-jet CRISLA are a thousand times higher than cold-wall CRISLA schemes, and thus preferred for large-quantity Uranium enrichments. For small-quantity separations of (radioactive) medical isotopes, the simpler coldwall CRISLA method may be adequate.

  10. Overview of the U.S. Department of Energy's Isotope Programs

    SciTech Connect (OSTI)

    Carty, J.

    2004-10-05

    This presentation provides an overview of the U.S. Department of Energy's Isotopes Program. The charter of the Isotope Programs covers the production and sale of radioactive and stable isotopes, associated byproducts, surplus materials, and related isotope services.

  11. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    M. Lozada-Hidalgo; S. Hu; O. Marshall; A. Mishchenko; A. N. Grigorenko; R. A. W. Dryfe; B. Radha; I. V. Grigorieva; A. K. Geim

    2015-11-20

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  12. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1993-01-01

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  13. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  14. Apparatus for separating and recovering hydrogen isotopes

    DOE Patents [OSTI]

    Heung, Leung K. (Aiken, SC)

    1994-01-01

    An apparatus for recovering hydrogen and separating its isotopes. The apparatus includes a housing bearing at least a fluid inlet and a fluid outlet. A baffle is disposed within the housing, attached thereto by a bracket. A hollow conduit is coiled about the baffle, in spaced relation to the baffle and the housing. The coiled conduit is at least partially filled with a hydride. The hydride can be heated to a high temperature and cooled to a low temperature quickly by circulating a heat transfer fluid in the housing. The spacing between the baffle and the housing maximizes the heat exchange rate between the fluid in the housing and the hydride in the conduit. The apparatus can be used to recover hydrogen isotopes (protium, deuterium and tritium) from gaseous mixtures, or to separate hydrogen isotopes from each other.

  15. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    Lozada-Hidalgo, M; Marshall, O; Mishchenko, A; Grigorenko, A N; Dryfe, R A W; Radha, B; Grigorieva, I V; Geim, A K

    2015-01-01

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  16. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

  17. PHYSICAL, MAGNETIC, SEDIMENTOLOGICAL, GEOCHEMICAL, ISOTOPIC AND MICROPALEONTOLOGICAL FEATURES OF RAPIDLY DEPOSITED

    E-Print Network [OSTI]

    PHYSICAL, MAGNETIC, SEDIMENTOLOGICAL, GEOCHEMICAL, ISOTOPIC AND MICROPALEONTOLOGICAL FEATURES Sediments, Québec City. Symposium preceedings: 103-108. ABSTRACT: Sedimentological, geochemical, isotopic

  18. Method for production of an isotopically enriched compound

    DOE Patents [OSTI]

    Watrous, Matthew G.

    2012-12-11

    A method is presented for producing and isolating an isotopically enriched compound of a desired isotope from a parent radionuclide. The method includes forming, or placing, a precipitate containing a parent radionuclide of the desired daughter isotope in a first reaction zone and allowing sufficient time for the parent to decay into the desired gaseous daughter radioisotope. The method further contemplates collecting the desired daughter isotope as a solid in a second reaction zone through the application of temperatures below the freezing point of the desired isotope to a second reaction zone that is connected to the first reaction zone. Specifically, a method is presented for producing isotopically enriched compounds of xenon, including the radioactive isotope Xe-131m and the stable isotope Xe-131.

  19. Isotope and Temperature Effects in Liquid Water Probed by Soft...

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

    Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Print Wednesday, 24 September 2008 00:00...

  20. Oxygen isotope records of carboniferous seasonality on the Russian platform 

    E-Print Network [OSTI]

    Wang, Huayu

    1998-01-01

    Seven isotopic and eight trace element (TE) profiles across shell growth lines are presented, based on over 1000 stable isotope and electron microprobe analyses on six brachiopod shells (Gigantoproductus), to quantify seasonal temperature change...

  1. Physiology of multiple sulfur isotope fractionation during microbial sulfate reduction

    E-Print Network [OSTI]

    Sim, Min Sub

    2012-01-01

    Microbial sulfate reduction (MSR) utilizes sulfate as an electron acceptor and produces sulfide that is depleted in heavy isotopes of sulfur relative to starting sulfate. The fractionation of S-isotopes is commonly used ...

  2. Hydrogen isotope fractionation during lipid biosynthesis by Haloarcula marismortui

    E-Print Network [OSTI]

    Hydrogen isotope fractionation during lipid biosynthesis by Haloarcula marismortui Sitindra S studied the controls on the fractionation of hydrogen isotopes during lipid biosynthesis by Haloarcula marismortui, a halophilic archaea, in pure culture experiments by varying organic substrate, the hydrogen

  3. Isotopic abundance in atom trap trace analysis

    DOE Patents [OSTI]

    Lu, Zheng-Tian; Hu, Shiu-Ming; Jiang, Wei; Mueller, Peter

    2014-03-18

    A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

  4. Coherent photonuclear reactions for isotope transmutation

    E-Print Network [OSTI]

    H. Ejiri; S. Date

    2011-02-22

    Coherent photonuclear isotope transmutation (CPIT) produces exclusively radioactive isotopes (RIs) by coherent photonuclear reactions via E1 giant resonances. Photons to be used are medium energy photons produced by laser photons backscattered off GeV electrons. The cross sections are as large as 0.2 - 0.6 b, being independent of individual nuclides. A large fraction of photons is effectively used for the photonuclear reactions, while the scattered GeV electrons remain in the storage ring to be re-used. CPIT with medium energy photons provides specific/desired RIs with the high rate and the high density for nuclear science, molecular biology and for nuclear medicines.

  5. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    Natural convection can provide adequate heat distribution in many situtations that arise in buildings. This is appropriate, for example, in passive solar buildings where some rooms tend to be more strongly solar heated than others or to reduce the number of heating units required in a building. Natural airflow and heat transport through doorways and other internal building apertures is predictable and can be accounted for in the design. The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Natural convective loops that can occur in buildings are described and a few design guidelines are presented.

  6. Geochemical and isotopic variations in shallow groundwater in areas of the Fayetteville Shale development, north-central Arkansas q

    E-Print Network [OSTI]

    Jackson, Robert B.

    Geochemical and isotopic variations in shallow groundwater in areas of the Fayetteville Shale of unconventional natural gas reservoirs such as impermeable shale basins through the use of horizontal drilling effects; the possible degradation of water quality in shallow aquifers over- lying producing shale

  7. Quantification and isotopic analysis of nitrogen in rocks at the ppm level using sealed tube combustion technique: A prelude to

    E-Print Network [OSTI]

    Cartigny, Pierre

    composition of natural samples is only modified after mixing and/or fractionation related to physico technique used for the determination of N isotopic composition in various rocks characterized by low N vacuum. The nitrogen gas purified using Cu, CuO and CaO, is quantified as dinitrogen N2 by capacitance

  8. Primitive off-rift basalts from Iceland and Jan Mayen: Os-isotopic evidence for a mantle source containing

    E-Print Network [OSTI]

    Lee, Cin-Ty Aeolus

    Primitive off-rift basalts from Iceland and Jan Mayen: Os-isotopic evidence for a mantle source Volcanological Center, Institute of Earth Sciences, University of Iceland, Reykjavik, Iceland d Natural History elements, are presented for basalts from the three volcanic flank zones in Iceland and from Jan Mayen

  9. Alkyl group substitution by oxime-bound palladium(II) (the Shaw reaction): Alkly group selectivity and deuterium isotope effects

    SciTech Connect (OSTI)

    Wells, A.P.; Kitching, W.

    1992-08-01

    This report provides information regarding the selectivity of alkyl groups and the nature of the transition state for C-H palladation by oxime-bound palladium(II) (the Shaw reaction). The kinetic deuterium isotope effects are also presented. 21 refs.

  10. Isotopic generator for bismuth-212 and lead-212 from radium

    DOE Patents [OSTI]

    Atcher, Robert W. (Kensington, MD); Friedman, Arnold M. (Park Forest, IL); Hines, John (Glen Ellyn, IL)

    1987-01-01

    A method and apparatus for providing radionuclides of bismuth-212 and lead-212. Thorium-228 and carrier solution starting material is input to a radiologically contained portion of an isotopic generator system, and radium-224 is separated from thorium-228 which is retained by a strongly basic anion exchange column. The separated radium-224 is transferred to an accessible, strongly acidic cationic exchange column. The cationic column retains the radium-224, and natural radioactive decay generates bismuth-212 and lead-212. The cationic exchange column can also be separated from the contained portion of the system and utilized without the extraordinary safety measures necessary in the contained portion. Furthermore, the cationic exchange column provides over a relatively long time period the short lived lead-212 and bismuth-212 radionuclides which are useful for a variety of medical therapies.

  11. Stable carbon and nitrogen isotope enrichment in primate tissues

    E-Print Network [OSTI]

    Crowley, Brooke E.; Carter, Melinda L.; Karpanty, Sarah M.; Zihlman, Adrienne L.; Koch, Paul L.; Dominy, Nathaniel J.

    2010-01-01

    of sample treatment and diagenesis on the isotopic integrityHare PE (1986) Effects of diagenesis on strontium, carbon,

  12. Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

    E-Print Network [OSTI]

    J. Kathawa; C. Fry; M. Thoennessen

    2012-01-20

    Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  13. Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

    SciTech Connect (OSTI)

    Kathawa, J.; Fry, C.; Thoennessen, M., E-mail: thoennessen@nscl.msu.edu

    2013-01-15

    Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  14. Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes

    E-Print Network [OSTI]

    E. May; M. Thoennessen

    2011-09-08

    Currently, forty-one cesium, thirty-five lanthanum, thirty-two praseodymium, and thirty-one promethium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  15. Hydrogen isotope fractionation during lipid biosynthesis by Tetrahymena thermophila

    E-Print Network [OSTI]

    Hydrogen isotope fractionation during lipid biosynthesis by Tetrahymena thermophila Sitindra S Accepted 7 September 2013 Available online 16 September 2013 a b s t r a c t Hydrogen isotope ratio values from recording the hydrogen isotope composition of ambient water, dD values of lipids also depend

  16. Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes

    E-Print Network [OSTI]

    Gross, J L

    2011-01-01

    Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  17. Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes

    E-Print Network [OSTI]

    J. L. Gross; M. Thoennessen

    2011-09-28

    Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  18. Discovery of the actinium, thorium, protactinium, and uranium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-03-06

    Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  19. Evidence of magnetic isotope effects during thermochemical sulfate reduction

    E-Print Network [OSTI]

    Kaufman, Alan Jay

    such as adsorption of S-bearing com- pounds on surfaces of solids (13). Magnetic isotope effects are expressedEvidence of magnetic isotope effects during thermochemical sulfate reduction Harry Oduroa,b,1 S are attributed to a magnetic isotope effect (MIE) associated with the formation of thiol-disulfide, ion

  20. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-Print Network [OSTI]

    A. Nystrom; M. Thoennessen

    2011-02-11

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  1. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-Print Network [OSTI]

    Nystrom, A

    2011-01-01

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  2. 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

  3. Discovery of Samarium, Europium, Gadolinium, and Terbium Isotopes

    E-Print Network [OSTI]

    E. May; M. Thoennessen

    2012-01-19

    Currently, thirty-four samarium, thirty-four europium, thirty-one gadolinium, and thirty-one terbium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  4. Discovery of the astatine, radon, francium, and radium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-05-26

    Currently, thirty-nine astatine, thirty-nine radon, thirty-five francium, and thirty-four radium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  5. Discovery of the thallium, lead, bismuth, and polonium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-01-21

    Currently, forty-two thallium, forty-two lead, forty-one bismuth, and forty-two polonium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  6. Discovery of dysprosium, holmium, erbium, thulium and ytterbium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-05-26

    Currently, 31 dysprosium, 32 holmium, 32 erbium, 33 thulium and 31 ytterbium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  7. Discovery of Tantalum, Rhenium, Osmium, and Iridium Isotopes

    E-Print Network [OSTI]

    R. Robinson; M. Thoennessen

    2011-09-02

    Currently, thirty-eight tantalum, thirty-eight rhenium, thirty-nine osmium, and thirty-eight iridium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  8. Isotopic Tracking of Hanford 300 Area Derived Uranium in the Columbia River

    SciTech Connect (OSTI)

    Christensen, John N.; Dresel, P. Evan; Conrad, Mark E.; Patton, Gregory W.; DePaolo, Donald J.

    2010-10-31

    Our objectives in this study are to quantify the discharge rate of uranium (U) to the Columbia River from the Hanford Site's 300 Area, and to follow that U down river to constrain its fate. Uranium from the Hanford Site has variable isotopic composition due to nuclear industrial processes carried out at the site. This characteristic makes it possible to use high-precision isotopic measurements of U in environmental samples to identify even trace levels of contaminant U, determine its sources, and estimate discharge rates. Our data on river water samples indicate that as much as 3.2 kg/day can enter the Columbia River from the 300 Area, which is only a small fraction of the total load of dissolved natural background U carried by the Columbia River. This very low-level of Hanford derived U can be discerned, despite dilution to < 1 percent of natural background U, 350 km downstream from the Hanford Site. These results indicate that isotopic methods can allow the amounts of U from the 300 Area of the Hanford Site entering the Columbia River to be measured accurately to ascertain whether they are an environmental concern, or are insignificant relative to natural uranium background in the Columbia River.

  9. Isotope effect evidence for the zinc hydroxide mechanism of carbonic anhydrase catalyst

    SciTech Connect (OSTI)

    Paneth, P.; O'Leary, M.H.

    1987-03-24

    The carbon kinetic isotope effect on the enzymatic dehydration of HCO/sub 3//sup -/ ion is k/sup 12//k/sup 13/ = 1.011 and is independent, within experimental error, of the addition of sucrose, substitution of D/sub 2/O for H/sub 2/O, and substitution of enzyme-bound Zn/sup 2 +/ by Co/sup 2 +/. These results are consistent with a ping-pong mechanism in which proton transfer between enzyme and solvent is separated from HCO/sub 3//sup -/ dehydration. For the dehydration half-reaction, diffusional processes are severalfold faster than dehydration, and the rate-determining step is the dehydration itself. The intrinsic isotope effect is approximately 1.011, indicating that hydration of CO/sub 2/ occurs by reaction of zinc-bound OH/sup -/, rather than zinc-bound H/sub 2/O.

  10. Isotope effect evidence for the zinc hydroxide mechanism of carbonic anhydrase catalysis

    SciTech Connect (OSTI)

    Paneth, P.; O'Leary, M.H.

    1987-03-24

    The carbon kinetic isotope effect on the enzymatic dehydration of HCO/sub 3/- ion is k12/k13 = 1.011 and is independent, within experimental error, of the addition of sucrose, substitution of D/sub 2/O for H/sub 2/O, and substitution of enzyme-bound Zn/sup 2 +/ by Co/sup 2 +/. These results are consistent with a ping-pong mechanism in which proton transfer between enzyme and solvent is separated from HCO/sub 3/- dehydration. For the dehydration half-reaction, diffusional processes are severalfold faster than dehydration, and the rate-determining step is the dehydration itself. The intrinsic isotope effect is approximately 1.011, indicating that hydration of CO/sub 2/ occurs by reaction of zinc-bound OH-, rather than zinc-bound H/sub 2/O.

  11. Laser Isotope Enrichment for Medical and Industrial Applications

    SciTech Connect (OSTI)

    Leonard Bond

    2006-07-01

    Laser Isotope Enrichment for Medical and Industrial Applications by Jeff Eerkens (University of Missouri), Jay Kunze (Idaho State University), and Leonard Bond (Idaho National Laboratory) The principal isotope enrichment business in the world is the enrichment of uranium for commercial power reactor fuels. However, there are a number of other needs for separated isotopes. Some examples are: 1) Pure isotopic targets for irradiation to produce medical radioisotopes. 2) Pure isotopes for semiconductors. 3) Low neutron capture isotopes for various uses in nuclear reactors. 4) Isotopes for industrial tracer/identification applications. Examples of interest to medicine are targets to produce radio-isotopes such as S-33, Mo-98, Mo-100, W-186, Sn-112; while for MRI diagnostics, the non-radioactive Xe-129 isotope is wanted. For super-semiconductor applications some desired industrial isotopes are Si-28, Ga-69, Ge-74, Se-80, Te-128, etc. An example of a low cross section isotope for use in reactors is Zn-68 as a corrosion inhibitor material in nuclear reactor primary systems. Neutron activation of Ar isotopes is of interest in industrial tracer and diagnostic applications (e.g. oil-logging). . In the past few years there has been a sufficient supply of isotopes in common demand, because of huge Russian stockpiles produced with old electromagnetic and centrifuge separators previously used for uranium enrichment. Production of specialized isotopes in the USA has been largely accomplished using old ”calutrons” (electromagnetic separators) at Oak Ridge National Laboratory. These methods of separating isotopes are rather energy inefficient. Use of lasers for isotope separation has been considered for many decades. None of the proposed methods have attained sufficient proof of principal status to be economically attractive to pursue commercially. Some of the authors have succeeded in separating sulfur isotopes using a rather new and different method, known as condensation repression. In this scheme a gas, of the selected isotopes for enrichment, is irradiated with a laser at a particular wavelength that would excite only one of the isotopes. The entire gas is subject to low temperatures sufficient to cause condensation on a cold surface. Those molecules in the gas that the laser excited are not as likely to condense as are the unexcited molecules. Hence the gas drawn out of the system will be enriched in the isotope that was excited by the laser. We have evaluated the relative energy required in this process if applied on a commercial scale. We estimate the energy required for laser isotope enrichment is about 20% of that required in centrifuge separations, and 2% of that required by use of "calutrons".

  12. Chemical and isotopic kinetics of sulfate reduction by organic matter under hydrothermal conditions

    SciTech Connect (OSTI)

    Kaiser, C.J.

    1988-01-01

    This study investigated the feasibility of nonbacterial sulfate reduction by organic matter in geologic environments. Sulfate is reduced by dextrose under acidic conditions at temperatures of 230-270 C. Reaction products include sulfide and organic-sulfur compounds; sulfite, thiosulfate and elemental sulfur were not detected. The rate law for the initial one- or two-electron reduction of sulfate at 250C is first-order in bisulfate and about one-half-order in initial dextrose concentration, and shows a very strong dependence on pH. The kinetics of sulfate reduction by fructose at 250C are virtually the same. The lack of sulfate reduction by formaldehyde, methanol, ethanol and acetic acid at 250 C indicates that the reducing power of dextrose and fructose cannot be attributed to carbonyl, carboxyl or hydroxyl functional groups. The form of the rate law for sulfate reduction by dextrose and the presence of an induction period rather suggest that the initial reduction of sulfate occurs with free radicals derived from the thermal decomposition of the hexoses or their alteration products. The inferred sulfate-reduction reaction mechanism suggest that aqueous sulfate may be reduced to sulfide in geologic environments such as deep sedimentary basins. The observed acid-catalysis of the reaction in the laboratory may be supplanted by clay-mineral catalysis in geologic environments. Sulfur isotopes are fractionated during the reduction of sulfate by dextrose under hydrothermal conditions. Computer simulations of the isotopic evolution of the experiments suggest that sulfate-sulfide isotopic exchange largely controls the isotopic composition of sulfate and sulfide. The extent of isotopic fractionation due solely to sulfate reduction thus cannot be determined from the experiments

  13. Radioactive isotopes in Danish drinking water

    E-Print Network [OSTI]

    Radioactive isotopes in Danish drinking water Sven P. Nielsen Risø National Laboratory Working OF INVESTIGATION 11 3 DESCRIPTION OF INVESTIGATION 12 4 RADIOACTIVITY IN DRINKING WATER 13 5 SAMPLING 15 6 27 #12;4 #12;5 Preface This project for investigation of radioactivity in drinking water shall

  14. Water isotopes and the general circulation

    E-Print Network [OSTI]

    Noone, David

    quantities are equator to pole temperature gradient, and the vertical thermal stratification #12;Isotopic" is the fractionation factor is a function of temperature F depends on large scale circulation and thermal state Both, temperature gradient/condensation) 2. Entrainment of non-depleted water (humidity, stratification/sheer) #12

  15. INTRODUCTION The oxygen isotopic compositions of minerals

    E-Print Network [OSTI]

    González, Luis A.

    .5 ka) and the associated migration of prairie into and out of the area (the prairie period; Dorale et of the Gulf of Mexico, Pacific, andArctic air masses (Bryson, 1966; Fig. 1). Gulf of Mexico air sup- plies of Mexico air masses and its precipitation is isotopically more negative than gulf moisture (e.g., typically

  16. Utilization of Kinetic Isotope Effects for the Concentration of Tritium

    SciTech Connect (OSTI)

    Brown, Gilbert M.; Meyer, Thomas j.; Moyer, Bruce A.

    1999-06-01

    The objective of this research program is to develop methods for concentrating tritium in water based on large primary isotope effects in catalytic redox processes. Basic research is being conducted to develop the chemistry of a complete cyclic process. Because tritium (generally present as HTO) is in a rapidly established equilibrium with protio-water, it moves with groundwater and separation from water cannot be achieved by the usual pump-and-treat methods using sorbants. The general methodology developed in this work will be applicable to a number of DOE waste streams, and as a consequence of the process tritium will be incorporated into an organic compound that will not readily exchange the tritium with groundwater. The process to be developed will remove tritium from H2O by concentrating it with respect to protio-water. This research involves developing chemical cycles that produce high concentration factors for HTO and T2O based on the discrimination of C-H and C-T bonds in oxidation reactions. Several steps are required in a cyclic process for the concentration of tritium in water. In the first step the tritium is incorporated in an organic compound. H-T discrimination occurs as the tritium containing compound is oxidized in a step involving a Ru(IV) oxo complex. Strong primary kinetic isotope effects lead to the oxidation of C-H bonds in preference to C-T bonds, and this reaction leads to concentration of tritium in the organic compound. The reduced form of the ruthenium compound can be reoxidized so that the oxidation step can be made catalytic.

  17. Non-canonical mass laws in equilibrium isotopic fractionations: Evidence from the vapor pressure isotope effect of SF6

    E-Print Network [OSTI]

    Cartigny, Pierre

    Non-canonical mass laws in equilibrium isotopic fractionations: Evidence from the vapor pressure report experimental observations of the vapor pressure isotope effect, including 33 S/32 S and 34 S/32. That equilibrium involves a reversed vapor pressure isotope effect; i.e., vapor is between 2& and 3& higher in 34 S

  18. Strontium-isotope stratigraphy of Enewetak Atoll

    SciTech Connect (OSTI)

    Ludwig, K.R.; Halley, R.B.; Simmons, K.R.; Peterman, Z.E.

    1988-02-01

    /sup 87/Sr//sup 86/Sr ratios determined for samples from a 350 m core of Neogene lagoonal, shallow-water limestones from Enewetak Atoll display a remarkably informative trend. Like the recently published data for Deep Sea Drilling Project (DSDP) carbonates, /sup 87/Sr//sup 86/Sr at Enewetak increases monotonically but not smoothly from the early Miocene to the Pleistocene. The data show intervals of little or no change in /sup 87/Sr//sup 86/Sr, punctuated by sharp transitions to lower values toward greater core depths. The sharp transitions correlate with observed solution disconformities caused by periods of subaerial erosion, whereas the intervals of little or no change in /sup 87/Sr//sup 86/Sr correspond to intervals of rapid accumulation of shallow-water carbonate sediments. When converted to numerical ages using the published DSDP 590B trend, the best-resolved time breaks are at 282 m (12.3 to 18.2 Ma missing) and 121.6 m (3.0 to 5.3 Ma missing) below the lagoon floor. At Enewetak, Sr isotopes offer a stratigraphic resolution for these shallow-marine Neogene carbonates comparable to that of nannofossil zonation in deep-sea carbonates (0.3-3 m.y.). In addition, the correlation of times of Sr-isotope breaks at Enewetak with times of rapid Sr-isotope change in the DSDP 590B samples confirms the importance of sea-level changes in the evolution of global-marine Sr isotopes and shows that the Sr-isotope response to sea-level falls is rapid.

  19. Enriching stable isotopes: Alternative use for Urenco technology

    SciTech Connect (OSTI)

    Rakhorst, H.; de Jong, P.G.T.; Dawson, P.D.

    1996-12-31

    The International Urenco Group utilizes a technologically advanced centrifuge process to enrich uranium in the fissionable isotope {sup 235}U. The group operates plants in the United Kingdom, the Netherlands, and Germany and currently holds a 10% share of the multibillion dollar world enrichment market. In the early 1990s, Urenco embarked on a strategy of building on the company`s uniquely advanced centrifuge process and laser isotope separation (LIS) experience to enrich nonradioactive isotopes colloquially known as stable isotopes. This paper summarizes the present status of Urenco`s stable isotopes business.

  20. Method of preparing mercury with an arbitrary isotopic distribution

    DOE Patents [OSTI]

    Grossman, M.W.; George, W.A.

    1986-12-16

    This invention provides for a process for preparing mercury with a predetermined, arbitrary, isotopic distribution. In one embodiment, different isotopic types of Hg[sub 2]Cl[sub 2], corresponding to the predetermined isotopic distribution of Hg desired, are placed in an electrolyte solution of HCl and H[sub 2]O. The resulting mercurous ions are then electrolytically plated onto a cathode wire producing mercury containing the predetermined isotopic distribution. In a similar fashion, Hg with a predetermined isotopic distribution is obtained from different isotopic types of HgO. In this embodiment, the HgO is dissolved in an electrolytic solution of glacial acetic acid and H[sub 2]O. The isotopic specific Hg is then electrolytically plated onto a cathode and then recovered. 1 fig.

  1. ISOTOPIC RATIOS IN TITAN's METHANE: MEASUREMENTS AND MODELING

    SciTech Connect (OSTI)

    Nixon, C. A.; Achterberg, R. K.; Temelso, B.; Vinatier, S.; Bezard, B.; Coustenis, A.; Teanby, N. A.; Mandt, K. E.; Sherrill, C. D.; Irwin, P. G. J.; Jennings, D. E.; Romani, P. N.; Flasar, F. M.

    2012-04-20

    The existence of methane in Titan's atmosphere ({approx}6% level at the surface) presents a unique enigma, as photochemical models predict that the current inventory will be entirely depleted by photochemistry in a timescale of {approx}20 Myr. In this paper, we examine the clues available from isotopic ratios ({sup 12}C/{sup 13}C and D/H) in Titan's methane as to the past atmosphere history of this species. We first analyze recent infrared spectra of CH{sub 4} collected by the Cassini Composite Infrared Spectrometer, measuring simultaneously for the first time the abundances of all three detected minor isotopologues: {sup 13}CH{sub 4}, {sup 12}CH{sub 3}D, and {sup 13}CH{sub 3}D. From these we compute estimates of {sup 12}C/{sup 13}C = 86.5 {+-} 8.2 and D/H = (1.59 {+-} 0.33) Multiplication-Sign 10{sup -4}, in agreement with recent results from the Huygens GCMS and Cassini INMS instruments. We also use the transition state theory to estimate the fractionation that occurs in carbon and hydrogen during a critical reaction that plays a key role in the chemical depletion of Titan's methane: CH{sub 4} + C{sub 2}H {yields} CH{sub 3} + C{sub 2}H{sub 2}. Using these new measurements and predictions we proceed to model the time evolution of {sup 12}C/{sup 13}C and D/H in Titan's methane under several prototypical replenishment scenarios. In our Model 1 (no resupply of CH{sub 4}), we find that the present-day {sup 12}C/{sup 13}C implies that the CH{sub 4} entered the atmosphere 60-1600 Myr ago if methane is depleted by chemistry and photolysis alone, but much more recently-most likely less than 10 Myr ago-if hydrodynamic escape is also occurring. On the other hand, if methane has been continuously supplied at the replenishment rate then the isotopic ratios provide no constraints, and likewise for the case where atmospheric methane is increasing. We conclude by discussing how these findings may be combined with other evidence to constrain the overall history of the atmospheric methane.

  2. Natural air motion in passive buildings

    SciTech Connect (OSTI)

    Balcomb, J.D.; Jones, G.F.

    1985-01-01

    The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Natural convective loops that can occur in buildings are described and a few experimental results are presented. Observations of stratification are discussed, similitude experiments are described, and the beginnings of a complete-system mathematical model are presented.

  3. Method and apparatus for storing hydrogen isotopes. [stored as uranium hydride in a block of copper

    DOE Patents [OSTI]

    McMullen, J.W.; Wheeler, M.G.; Cullingford, H.S.; Sherman, R.H.

    1982-08-10

    An improved method and apparatus for storing isotopes of hydrogen (especially tritium) are provided. The hydrogen gas is stored as hydrides of material (for example uranium) within boreholes in a block of copper. The mass of the block is critically important to the operation, as is the selection of copper, because no cooling pipes are used. Because no cooling pipes are used, there can be no failure due to cooling pipes. And because copper is used instead of stainless steel, a significantly higher temperature can be reached before the eutectic formation of uranium with copper occurs, (the eutectic of uranium with the iron in stainless steel forms at a significantly lower temperature).

  4. Effect of sulfur isotopic composition of zinc and lead sulfides on the E. M. F. of electrochemical cells

    SciTech Connect (OSTI)

    Lusk, J.; Krouse, H.R.; Batts, B.D.

    1988-03-01

    A new effect is reported in which unexpectedly large voltages are produced by electrochemical cells containing sulfides at natural isotopic abundance levels. Room temperature experiments were undertaken to determine whether electrochemical cells employing silver bromide and silver beta alumina as solid electrolytes would be sufficiently sensitive to detect small variations in sulfur isotopic composition for zinc and lead sulfides. Voltages obtained for silver bromide cells tended to increase progressively over at least 20 days, and increased in a regular fashion with increasing differences in isotopic composition between charges. Voltages exceeding 150 mV were obtained for /sup delta/S/sup 3,4/ differences up to 85 per mil for zinc sulfide, but reached only about 20 mV for lead sulfide. Silver beta alumina cells with opposing zinc and lead sulfide charges yielded larger voltages and E.M.F. minimum corresponding to a +8(/plus minus/2) per mil difference. This value shows reasonable agreement with interpolated 20/degrees/C equilibrium values of between +7.5 to +9.8 obtained from the literature. Matured silver bromide cells with opposed zinc and lead sulfide charges behaved similarly but yielded lower voltages. Silver concentration cells of the opposed type are thus able to detect isotopic equilibrium and this will permit calibration of sulfur isotope thermometers down to unexpectedly low temperatures.

  5. Undesirable options - The U. S. isotope crisis

    SciTech Connect (OSTI)

    Not Available

    1993-04-01

    When a Canadian reactor failed in late 1990, it shut off a principle supply of iridium-192, an isotope critical to gamma radiography. Following the failure of the Canadian reactor, iridium sources inside the US were largely undependable in terms of both cost and schedule. The scheduling problems are outlined in the following testimony; prices increased 35% on one occasion, and then saw another increase of 60%. On August 3, 1992 Congressman Mike Synar requested that ASNT member Donny Dicharry present testimony on behalf of ASNT, the Nondestructive Testing Management Association (NDTMA), and Source Production and Equipment Co., Inc. (SPEC) concerning the Department of Energy's isotope program and the iridium-192 shortage. Excerpts from the testimony are given.

  6. Regioselective synthesis using the deuterium isotope effect

    SciTech Connect (OSTI)

    Miyano, M.

    1981-04-24

    Dehydration of 1a by various procedures invariably produced more exo olefin 2a than endo olefin 3a. This could be reversed by introduction of deuterium in the Me-21 group of the starting material. Thus, dehydration of 1b could afford more endo olefin 3b than exo olefin 2b due to the deuterium isotope effect. A regioselective synthesis of 18-oxoprogesterone (15a) from 3..beta..-hydroxypregn-5-en-20-one (5a) was carried out taking advantage of the deuterium isotope effect as depicted in Scheme I. The key steps were dehydration of 7b to predominantly endo olefin 9b and removal of the deuteriums from 18-oxoprogesterone-17..cap alpha..,21,21,21-d/sub 4/ (15b) to give 15a.

  7. Hydrogen isotopic exchange over palladium metal

    SciTech Connect (OSTI)

    Carstens, D.H.W.; Encinias, P.D.

    1990-01-01

    We have recently developed the laser-Raman technique as a means of unambiguously measuring the partial pressures of all possible hydrogen isotopes in the gas phase. Using this technique we have investigated the hydrogen-deuterium exchange in a number of metals. This report presents detailed data for isotopic exchange in the palladium hydride system over the temperature range 26{degree}C to -100{degree}C at a pressure of 7 atm. First order kinetic rate constants and activation energies are summarized for the forward (hydride to deuteride) and reverse (deuteride to hydride) exchange processes. In addition, we have found that small amounts (100 ppm) of impurities in the exchange gases considerably slow the exchange kinetics with the effect increasing down the series CH{sub 4}, CO{sub 2}, H{sub 2}O, and CO. 9 refs., 4 figs., 1 tab.

  8. Diffusional exchange of isotopes in a metal hydride sphere.

    SciTech Connect (OSTI)

    Wolfer, Wilhelm G.; Hamilton, John C.; James, Scott Carlton

    2011-04-01

    This report describes the Spherical Particle Exchange Model (SPEM), which simulates exchange of one hydrogen isotope by another hydrogen isotope in a spherical metal hydride particle. This is one of the fundamental physical processes during isotope exchange in a bed of spherical metal particles and is thus one of the key components in any comprehensive physics-based model of exchange. There are two important physical processes in the model. One is the entropy of mixing between the two isotopes; the entropy of mixing is increased by having both isotopes randomly placed at interstitial sites on the lattice and thus impedes the exchange process. The other physical process is the elastic interaction between isotope atoms on the lattice. The elastic interaction is the cause for {beta}-phase formation and is independent of the isotope species. In this report the coupled diffusion equations for two isotopes in the {beta}-phase hydride are solved. A key concept is that the diffusion of one isotope depends not only on its concentration gradient, but also on the concentration gradient of the other isotope. Diffusion rate constants and the chemical potentials for deuterium and hydrogen in the {beta}-phase hydride are reviewed because these quantities are essential for an accurate model of the diffusion process. Finally, a summary of some of the predictions from the SPEM model are provided.

  9. Quantifying uncertainty in stable isotope mixing models

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

    Davis, Paul; Syme, James; Heikoop, Jeffrey; Fessenden-Rahn, Julianna; Perkins, George; Newman, Brent; Chrystal, Abbey E.; Hagerty, Shannon B.

    2015-05-19

    Mixing models are powerful tools for identifying biogeochemical sources and determining mixing fractions in a sample. However, identification of actual source contributors is often not simple, and source compositions typically vary or even overlap, significantly increasing model uncertainty in calculated mixing fractions. This study compares three probabilistic methods, SIAR [Parnell et al., 2010] a pure Monte Carlo technique (PMC), and Stable Isotope Reference Source (SIRS) mixing model, a new technique that estimates mixing in systems with more than three sources and/or uncertain source compositions. In this paper, we use nitrate stable isotope examples (?15N and ?18O) but all methods testedmore »are applicable to other tracers. In Phase I of a three-phase blind test, we compared methods for a set of six-source nitrate problems. PMC was unable to find solutions for two of the target water samples. The Bayesian method, SIAR, experienced anchoring problems, and SIRS calculated mixing fractions that most closely approximated the known mixing fractions. For that reason, SIRS was the only approach used in the next phase of testing. In Phase II, the problem was broadened where any subset of the six sources could be a possible solution to the mixing problem. Results showed a high rate of Type I errors where solutions included sources that were not contributing to the sample. In Phase III some sources were eliminated based on assumed site knowledge and assumed nitrate concentrations, substantially reduced mixing fraction uncertainties and lowered the Type I error rate. These results demonstrate that valuable insights into stable isotope mixing problems result from probabilistic mixing model approaches like SIRS. The results also emphasize the importance of identifying a minimal set of potential sources and quantifying uncertainties in source isotopic composition as well as demonstrating the value of additional information in reducing the uncertainty in calculated mixing fractions.« less

  10. First AID (Atom counting for Isotopic Determination).

    SciTech Connect (OSTI)

    Roach, J. L. (Jeffrey L.); Israel, K. M. (Kimberly M.); Steiner, R. E. (Robert E.); Duffy, C. J. (Clarence J.); Roench, F. R. (Fred R.)

    2002-01-01

    Los Alamos National Laboratory (LANL) has established an in vitro bioassay monitoring program in compliance with the requirements in the Code of Federal Regulations, 10 CFR 835, Occupational Radiation Protection. One aspect of this program involves monitoring plutonium levels in at-risk workers. High-risk workers are monitored using the ultra-sensitive Therrnal Ionization Mass Spectrometry (TIMS) technique to ensure compliance with DOE standards. TIMS is used to measure atom ratios of 239Pua nd 240Puw ith respect to a tracer isotope ('Pu). These ratios are then used to calculate the amount of 239Pu and 240Pup resent. This low-level atom counting technique allows the calculation of the concentration levels of 239Pu and 240Pu in urine for at risk workers. From these concentration levels, dose assessments can be made and worker exposure levels can be monitored. Detection limits for TIMS analysis are on the order of millions of atoms, which translates to activity levels of 150 aCi 239Pua nd 500 aCi for 240Pu. pCi for Our poster presentation will discuss the ultra-sensitive, low-level analytical technique used to measure plutonium isotopes and the data verification methods used for validating isotopic measurements.

  11. Hydrogen isotope separation utilizing bulk getters

    DOE Patents [OSTI]

    Knize, Randall J. (Los Angeles, CA); Cecchi, Joseph L. (Lawrenceville, NJ)

    1991-01-01

    Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen.

  12. Hydrogen isotope separation utilizing bulk getters

    DOE Patents [OSTI]

    Knize, R.J.; Cecchi, J.L.

    1991-08-20

    Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen. 4 figures.

  13. Hydrogen isotope separation utilizing bulk getters

    DOE Patents [OSTI]

    Knize, Randall J. (Los Angeles, CA); Cecchi, Joseph L. (Lawrenceville, NJ)

    1990-01-01

    Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen.

  14. FIRE /SMOKE The most effective method of fighting fires is to prevent them from occurring. All

    E-Print Network [OSTI]

    Jia, Songtao

    FIRE /SMOKE The most effective method of fighting fires is to prevent them from occurring. All-305-7979 (CUMC) after evacuating. Procedures for UNCONTROLLABLE FIRES DO NOT stay to fight a large or rapidly

  15. Microbial Biogeochemistry Chemical reactions occurring in the environment mediated by microbial communities

    E-Print Network [OSTI]

    Vallino, Joseph J.

    Microbial Biogeochemistry Chemical reactions occurring in the environment mediated by microbial communities Outline · Metabolic Classifications. · Winogradsky columns, Microenvironments. · Redox Reactions Chemical (Chemotrophs) Inorganic (Chemolithotrophs) Aerobic (majority) Anaerobic (few) Organic

  16. Importance of the Equlibrium Node in Preventing the Voltage Collapse Occurs in the Wind Power System

    E-Print Network [OSTI]

    Lavaei, Javad

    or insufficient reactive power supplies may also contribute to voltage collapse and blackouts. In recent years, the voltage collapse or blackouts have occurred worldwide, such as the blackout in France at 1978 and blackout

  17. Isotope shifts in francium isotopes Fr 206 - 213 and Fr 221

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

    Collister, R.; Gwinner, G.; Tandecki, M.; Behr, J. A.; Pearson, M. R.; Zhang, J.; Orozco, L. A.; Aubin, S.; Gomez, E.; FrPNC Collaboration

    2014-11-07

    We present the isotope shifts of the 7s1/2 to 7p1/2 transition for francium isotopes ²???²¹³Fr with reference to ²²¹Fr collected from two experimental periods. The shifts are measured on a sample of atoms prepared within a magneto-optical trap by a fast sweep of radio-frequency sidebands applied to a carrier laser. King plot analysis, which includes literature values for 7s1/2 to 7p3/2 isotope shifts, provides a field shift constant ratio of 1.0520(10) and a difference between the specific mass shift constants of 170(100) GHz amu between the D? and D? transitions, of sufficient precision to differentiate between ab initio calculations.

  18. Isotope shifts in francium isotopes Fr 206 - 213 and Fr 221

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

    Collister, R.; Gwinner, G.; Tandecki, M.; Behr, J. A.; Pearson, M. R.; Zhang, J.; Orozco, L. A.; Aubin, S.; Gomez, E.; FrPNC Collaboration

    2014-11-01

    We present the isotope shifts of the 7s1/2 to 7p1/2 transition for francium isotopes ²???²¹³Fr with reference to ²²¹Fr collected from two experimental periods. The shifts are measured on a sample of atoms prepared within a magneto-optical trap by a fast sweep of radio-frequency sidebands applied to a carrier laser. King plot analysis, which includes literature values for 7s1/2 to 7p3/2 isotope shifts, provides a field shift constant ratio of 1.0520(10) and a difference between the specific mass shift constants of 170(100) GHz amu between the D? and D? transitions, of sufficient precision to differentiate between ab initio calculations.

  19. System and method for high precision isotope ratio destructive analysis

    SciTech Connect (OSTI)

    Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

    2013-07-02

    A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

  20. Coupled variations in helium isotopes and fluid chemistry: Shoshone Geyser Basin, Yellowstone National Park

    SciTech Connect (OSTI)

    Hearn, E.H.; Kennedy, B.M. (Univ. of California, Berkeley (USA)); Truesdell, A.H. (Geological Survey, Menlo Park, CA (USA))

    1990-11-01

    Early studies of {sup 3}He/{sup 4}He variations in geothermal systems have generally attributed these fluctuations to either differences in the source of the magmatic {sup 3}He-rich helium or to local differences in the deep flux of magmatic {sup 3}He-rich helium. Kennedy et al, however, show that near-surface processes such as boiling and dilution may also drastically affect {sup 3}He/{sup 4}He ratios of geothermal vapors. Helium isotope ratios were determined for several hot springs at Shoshone Geyser Basin of Yellowstone National Park for this study, along with other noble gas data. Stable isotope data and water and gas chemistry data for each spring were also compiled. The water chemistry indicates that there is one deep, hot thermal water in the area which is mixing with dilute meteoric water that has entered the system at depth. Spring HCO{sub 3}{sup {minus}} concentrations correlate with {sup 3}He/{sup 4}He values, as in nearby Lower Geyser Basin. This correlation is attributed to variable amounts of deep dilution of thermal waters with a relatively cool water that inhibits boiling at depth, thus preventing the loss of CO{sub 2} and magmatic He in the most diluted samples. Oxygen and hydrogen isotope data also support a boiling and dilution model, but to produce the observed fractionations, the boiling event would have to be extensive, with steam loss at the surface, whereas the boiling that affected the helium isotope ratios was probably a small scale event with steam loss at depth. It is possible that deep boiling occurred in the basin and that small amounts of steam escaped along fractures at about 500 m below the surface while all subsequently produced steam was lost near or at the surface.

  1. Isotopic identification of soil and permafrost nitrate sources in an Arctic tundra ecosystem

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

    Heikoop, Jeffrey M.; Throckmorton, Heather M.; Newman, Brent D.; Perkins, George B.; Iversen, Colleen M.; Chowdhury, Taniya Roy; Romanovsky, Vladimir E.; Graham, David E.; Norby, Richard J.; Wilson, Cathy J.; et al

    2015-06-08

    The nitrate (NO??) dual isotope approach was applied to snowmelt, tundra active layer pore waters, and underlying permafrost in Barrow, Alaska, USA, to distinguish between NO?? derived from at NO?? signal with ?¹?N averaging –4.8 ± 1.0‰ (standard error of the mean) and ?¹?O averaging 70.2 ±1.7‰. In active layer pore waters, NO?? primarily occurred at concentrations suitable for isotopic analysis in the relatively dry and oxic centers of high-centered polygons. The average ?¹?N and ?¹?O of NO?? from high-centered polygons were 0.5 ± 1.1‰ and –4.1 ± 0.6‰, respectively. When compared to the ?¹?N of reduced nitrogen (N) sources,more »and the ?¹?O of soil pore waters, it was evident that NO?? in high-centered polygons was primarily from microbial nitrification. Permafrost NO?? had ?¹?N ranging from approximately –6‰ to 10‰, similar to atmospheric and microbial NO??, and highly variable ?¹?O ranging from approximately –2‰ to 38‰. Permafrost ice wedges contained a significant atmospheric component of NO??, while permafrost textural ice contained a greater proportion of microbially derived NO??. Large-scale permafrost thaw in this environment would release NO?? with a ?¹?O signature intermediate to that of atmospheric and microbial NO?. Consequently, while atmospheric and microbial sources can be readily distinguished by the NO?? dual isotope technique in tundra environments, attribution of NO?? from thawing permafrost will not be straightforward. The NO?? isotopic signature, however, appears useful in identifying NO?? sources in extant permafrost ice.« less

  2. Isotopic Analysis- Fluid At Dixie Valley Geothermal Area (Kennedy...

    Open Energy Info (EERE)

    this study was to investigate the relationship between known geothermal resources with deep, fault hosted permeable fluid flow pathways and the helium Isotopic composition of the...

  3. Hydrogeological And Isotopic Survey Of Geothermal Fields In The...

    Open Energy Info (EERE)

    Hydrogeological And Isotopic Survey Of Geothermal Fields In The Buyuk Menderes Graben, Turkey Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  4. Isotopic Analysis At Valles Caldera - Redondo Geothermal Area...

    Open Energy Info (EERE)

    Isotopic Analysis- Rock Activity Date - 2004 Usefulness useful regional reconnaissance DOE-funding Unknown Exploration Basis The study was undertaken to refine understanding of...

  5. Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area...

    Open Energy Info (EERE)

    Area Exploration Technique Isotopic Analysis- Rock Activity Date Usefulness not indicated DOE-funding Unknown References Hisatoshi Ito, Kazuhiro Tanaka (1995) Insights On The...

  6. Isotopic Analysis- Rock At Kilauea East Rift Geothermal Area...

    Open Energy Info (EERE)

    Technique Isotopic Analysis- Rock Activity Date 1989 - 2000 Usefulness not indicated DOE-funding Unknown Exploration Basis The purpose of this study was to analyze deep core...

  7. Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Geothermal...

    Open Energy Info (EERE)

    Isotopic Analysis- Rock Activity Date - 2004 Usefulness useful regional reconnaissance DOE-funding Unknown Exploration Basis The study was undertaken to refine understanding of...

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

    Open Energy Info (EERE)

    Stable-isotope analyses were carried out on hydrothermal minerals sampled from the deep metamorphic units at Larderello, Italy. The D18O values obtained for the most...

  11. Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (Rao...

    Open Energy Info (EERE)

    Fluid At Valles Caldera - Redondo Area (Rao, Et Al., 1996) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Valles...

  12. Isotopic Analysis- Fluid At Fenton Hill HDR Geothermal Area ...

    Open Energy Info (EERE)

    Geothermal Area (Rao, Et Al., 1996) Exploration Activity Details Location Fenton Hill HDR Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1996 - 1996...

  13. Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs...

    Open Energy Info (EERE)

    Et Al., 1996) Exploration Activity Details Location Valles Caldera - Sulphur Springs Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1996 - 1996...

  14. Isotope Geochemistry of Thermal and Nonthermal Waters in the...

    Open Energy Info (EERE)

    Canyon. Isotopic evidence shows that these springs consist of three components: (1) deep geothermal fluid, (2) surficial andor near-surface groundwater, and (3) relatively old,...

  15. Chemical and isotopic characteristics of the coso east flank...

    Open Energy Info (EERE)

    Christenson, B. W.; Kennedy, B. M.; Adams, M. C.; Bjornstad, S. C.; Buck, C. . 182007. Chemical and isotopic characteristics of the coso east flank hydrothermal fluids:...

  16. Isotopic Composition of Carbon in Fluids from the Long Valley...

    Open Energy Info (EERE)

    Isotopic Composition of Carbon in Fluids from the Long Valley Geothermal System, California, In- Proceedings of the Second Workshop on Hydrologic and Geochemical Monitoring in the...

  17. Temperature effects on the behavior of liquid hydrogen isotopes...

    Office of Scientific and Technical Information (OSTI)

    liquid hydrogen isotopes inside a spherical-shell directly driven inertial confinement fusion target Kim, K.; Mok, L.S. 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; LASER TARGETS;...

  18. A Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal...

    Open Energy Info (EERE)

    System. Geothermics. () . Related Geothermal Exploration Activities Activities (4) Direct-Current Resistivity Survey At Dixie Valley Geothermal Area (Laney, 2005) Isotopic...

  19. Hydrochemical and isotopic effects associated with petroleum fuel biodegradation pathways

    E-Print Network [OSTI]

    Sheffield, University of

    Hydrochemical and isotopic effects associated with petroleum fuel biodegradation pathways attenuation capacity in this dual- porosity aquifer. D 2005 Published by Elsevier B.V. Keywords: MTBE; BTEX

  20. Chemical and Isotopic Prediction of Aquifer Temperatures in the...

    Open Energy Info (EERE)

    Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Chemical and Isotopic Prediction of Aquifer Temperatures in the Geothermal System at Long...

  1. Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs...

    Open Energy Info (EERE)

    Fluid Activity Date - 1982 Usefulness useful DOE-funding Unknown Notes Field, chemical, and isotopic data for 95 thermal and nonthermal waters in and around the Valles...

  2. Isotopic Analysis At Valles Caldera - Redondo Geothermal Area...

    Open Energy Info (EERE)

    Fluid Activity Date - 1982 Usefulness useful DOE-funding Unknown Notes Field, chemical, and isotopic data for 95 thermal and nonthermal waters in and around the Valles...

  3. Chemical And Isotopic Investigation Of Warm Springs Associated...

    Open Energy Info (EERE)

    Chemical And Isotopic Investigation Of Warm Springs Associated With Normal Faults In Utah Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  4. Chemical and light-stable isotope characteristics of waters from...

    Open Energy Info (EERE)

    Chemical and light-stable isotope characteristics of waters from the raft river geothermal area and environs, Cassia County, Idaho, Box Elder county, Utah Jump to: navigation,...

  5. Secretary Moniz on Natural Gas and Renewables | Department of...

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

    Secretary Moniz on Natural Gas and Renewables Secretary Moniz on Natural Gas and Renewables Addthis An error occurred. Try watching this video on www.youtube.com, or enable...

  6. Nuclear Proliferation Using Laser Isotope Separation -- Verification Options

    SciTech Connect (OSTI)

    Erickson, S A

    2001-10-15

    Two levels of nonproliferation verification exist. Signatories of the basic agreements under the Nuclear Non-proliferation Treaty (NPT) agree to open their nuclear sites to inspection by the IAEA. A more detailed and intrusive level was developed following the determination that Iraq had begun a nuclear weapons development program that was not detected by the original level of verification methods. This level, referred to as 93+2 and detailed in model protocol INFCIRC/540, allows the IAEA to do environmental monitoring of non-declared facilities that are suspected of containing proliferation activity, and possibly further inspections, as well as allowing more detailed inspections of declared sites. 56 countries have signed a Strengthened Safeguards Systems Additional Protocol as of 16 July 2001. These additional inspections can be done on the instigation of the IAEA itself, or after requests by other parties to the NPT, based on information that they have collected. Since information able to cause suspicion of proliferation could arrive at any country, it is important that countries have procedures in place that will assist them in making decisions related to these inspections. Furthermore, IAEA inspection resources are limited, and therefore care needs to be taken to make best use of these resources. Most of the nonproliferation verification inspections may be concentrated on establishing that diversion of nuclear materials is not occurring, but some fraction will be related to determining if undeclared sites have nuclear materials production taking place within them. Of these, most suspicions will likely be related to the major existing technologies for uranium enrichment and reprocessing for plutonium extraction, as it would seem most likely that nations attempting proliferation would use tested means of producing nuclear materials. However, as technology continues to advance and new methods of enrichment and reprocessing are developed, inspection-related procedures will need to be adapted to keep up with them. In order to make 93+2 inspections more useful, a systematic way of finding clues to nuclear proliferation would be useful. Also, to cope with the possible use of newer technology for proliferation, the list of clues might need to be expanded. This paper discusses the development and recognition of such clues. It concentrates on laser isotope separation (LIS) as a new proliferation technology, and uses Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) as an example of LIS that is well known.

  7. Nature's software

    E-Print Network [OSTI]

    Daniel Canarutto

    2014-04-20

    I bring forward some arguments to support the thesis that nature is fundamentally discrete, and present my own thoughts about the direction in which one could look for a possible, consistent "theory of everything" describing gravitation and quantum particles.

  8. Apparatus for isotopic alteration of mercury vapor

    DOE Patents [OSTI]

    Grossman, Mark W. (Belmont, MA); George, William A. (Gloucester, MA); Marcucci, Rudolph V. (Danvers, MA)

    1988-01-01

    An apparatus for enriching the isotopic Hg content of mercury is provided. The apparatus includes a reactor, a low pressure electric discharge lamp containing a fill including mercury and an inert gas. A filter is arranged concentrically around the lamp. In a preferred embodiment, constant mercury pressure is maintained in the filter by means of a water-cooled tube that depends from it, the tube having a drop of mercury disposed in it. The reactor is arranged around the filter, whereby radiation from said lamp passes through the filter and into said reactor. The lamp, the filter and the reactor are formed of a material which is transparent to ultraviolet light.

  9. Final Report "Structure of Rare Isotopes"

    SciTech Connect (OSTI)

    Papenbrock, Thomas

    2012-05-09

    The Junior Investigator grant 'Structure of Rare Isotopes' (DE-FG02-07ER41529) supported research in low-energy nuclear theory from September 1, 2007 to August 31, 2010. It was the main goal of the proposed research to develop and optimize an occupation-number-based energy functional for the computation of nuclear masses, and this aim has been reached. Furthermore, progress was made in linking two and three-body forces from low-momentum interactions to pairing properties in nuclear density functionals, and in the description of deformed nuclei within an effective theory.

  10. Production of radioactive isotopes through cosmic muon spallation in KamLAND

    SciTech Connect (OSTI)

    Abe, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Kibe, Y.; Kishimoto, Y.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.

    2010-02-15

    Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in nu detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillators, and for checking estimates from current simulations based upon MUSIC, FLUKA, and GEANT4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be Y{sub n}=(2.8+-0.3)x10{sup -4} mu{sup -1} g{sup -1} cm{sup 2}. For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  11. Study of the Production of Radioactive Isotopes through Cosmic Muon Spallation in KamLAND

    SciTech Connect (OSTI)

    KamLAND Collaboration; Abe, S.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.; Yonezawa, E.; Yoshida, S.; Kozlov, A.; Murayama, H.; Busenitz, J.; Classen, T.; Grant, C.; Keefer, G.; Leonard, D. S.; McKee, D.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Gray, F.; Guardincerri, E.; Hsu, L.; Ichimura, K.; Kadel, R.; Lendvai, C.; Luk, K.-B.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D. A.; Jillings, C.; Mauger, C.; McKeown, R. D.; Vogel, P.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Piquemal, F.; Ricol, J.-S.; Decowski, M. P.

    2009-06-30

    Radioactive isotopes produced through cosmic muon spallation are a background for rare event detection in {nu} detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillator, and for checking estimates from current simulations based upon MUSIC, FLUKA, and Geant4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be (2.8 {+-} 0.3) x 10{sup -4} n/({mu} {center_dot} (g/cm{sup 2})). For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  12. 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

  13. Molecular modeling of slip supposed to occur in the shock initiation of crystalline PETN

    SciTech Connect (OSTI)

    Ritchie, J.P.

    1992-12-01

    Some molecular modeling of slip using both rigid and flexible molecules of PETN in perfect, but finite, lattices has been performed. Results show that it is likely that molecular deformations occur and have an important effect in determining the shear strength.

  14. The blue shark (Prionace glauca) is an oceanic species that occurs in tem-

    E-Print Network [OSTI]

    720 The blue shark (Prionace glauca) is an oceanic species that occurs in tem- perate and tropical); numerically, the blue shark is the top nontarget species captured by the U.S. longline pelagic Atlantic fleet) on the catch rate of several target and bycatch species, including the blue shark. However, they did

  15. Mdm10 is an ancient eukaryotic porin co-occurring with the ERMES complex

    E-Print Network [OSTI]

    Just, Armin

    Mdm10 is an ancient eukaryotic porin co-occurring with the ERMES complex Nadine Flinner a , Lars -barrel protein Multiple sequence alignment Homology modeling Phylogenetic analysis ERMES SAM mitochondria encounter structure (ERMES), which tethers the ER to mitochondria and associates with the SAM

  16. Planetary and Space Science 56 (2008) 17781784 Predictions and observations of events and configurations occurring

    E-Print Network [OSTI]

    Sicardy, Bruno

    2008-01-01

    and configurations occurring during the Uranian equinox Jean-Eudes ArlotÃ, Bruno Sicardy Paris Observatory of difficulties due to the faintness of the Uranian satellites and this proximity to the planet. 2. The equinox, 1990; Arlot, 2002; Arlot et al., 2006a, b). The equinox on Jupiter takes place every 6 years allowing

  17. Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species

    E-Print Network [OSTI]

    Jackson, Robert B.

    Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species induced by drought but in many cases, not by freezing. Rarely have vulnerability to drought and freezing and distribution of plants in many regions of the world. We studied vulnerability to drought- and freezing- induced

  18. New species of Mycosphaerella occurring on Eucalyptus leaves in Indonesia and Africa

    E-Print Network [OSTI]

    781 New species of Mycosphaerella occurring on Eucalyptus leaves in Indonesia and Africa P.W. Crous and M.J. Wingfield Ahstract:Although Africa and Indonesia have not been particularly well surveyed Eucalyptus leaves from Indonesia. The former species is of particular interest, because its anamorph

  19. Enhanced Longevity by Ibuprofen, Conserved in Multiple Species, Occurs in Yeast through Inhibition of Tryptophan Import 

    E-Print Network [OSTI]

    He, Chong; Tsuchiyama, Scott K.; Nguyen, Quynh T.; Plyusnina, Ekaterina N.; Terrill, Samuel R.; Sahibzada, Sarah; Patel, Bhumil; Faulkner, Alena R.; Shaposhnikov, Mikhail V.; Tian, Ruilin; Tsuchiya, Mitsuhiro; Kaeberlein, Matt; Moskalev, Alexey A.; Kennedy, Brian K.; Polymenis, Michael

    2014-12-18

    by Ibuprofen, Conserved in Multiple Species, Occurs in Yeast through Inhibition of Tryptophan Import Chong He1, Scott K. Tsuchiyama1, Quynh T. Nguyen2, Ekaterina N. Plyusnina3,4, Samuel R. Terrill2, Sarah Sahibzada2, Bhumil Patel1, Alena R. Faulkner1, Mikhail V...

  20. Endophytic and canker-associated Botryosphaeriaceae occurring on non-native Eucalyptus and native Myrtaceae

    E-Print Network [OSTI]

    Endophytic and canker-associated Botryosphaeriaceae occurring on non-native Eucalyptus and native associated with stem cankers on plantation-grown Eucalyptus globulus. Howev- er, very little is known their relationship is to those species infecting Eucalyptus in plantations. The objectives of this study were

  1. A multi-gene phylogeny for species of Mycosphaerella occurring on Eucalyptus leaves

    E-Print Network [OSTI]

    147 A multi-gene phylogeny for species of Mycosphaerella occurring on Eucalyptus leaves Gavin C Eucalyptus spp. where they cause leaf diseases collectively known as Mycosphaerella Leaf Disease (MLD Eucalyptus. A further aim was to study the anamorph concepts and resolve the deeper nodes of Mycosphaerella

  2. "Climate change is sure to occur in some form." The study of climate impacts notes

    E-Print Network [OSTI]

    "Climate change is sure to occur in some form." 1 #12;The study of climate impacts notes how scientists generally agree that humans are changing the climate, and that if we continue pumping carbon we learn from past climate variations? How can we best adapt to climate change? This report attempts

  3. Introduction Neutral grasslands occur throughout the UK on soils where the pH is within

    E-Print Network [OSTI]

    Introduction Neutral grasslands occur throughout the UK on soils where the pH is within the range 5 by grasses and herbs (Figure 1). The term `neutral', although indicative of soil pH, is more correctly descriptive of the species assemblage being neither markedly `calcifuge' (thriving in acid soils) nor

  4. EMERGENCY PROCEDURES Many types of emergencies can occur on campus; instructions for specific emergencies such as

    E-Print Network [OSTI]

    Capogna, Luca

    EMERGENCY PROCEDURES Many types of emergencies can occur on campus; instructions for specific emergencies such as severe weather, active shooter, or fire can be found at emergency.uark.edu. Severe Weather (Tornado Warning): · Follow the directions of the instructor or emergency personnel · Seek shelter

  5. between the nucleus and cytoplasm occurs through large macromolecular structures, the nuclear pores. Quantitative

    E-Print Network [OSTI]

    Forbes, Douglass

    363 between the nucleus and cytoplasm occurs through large macromolecular structures, the nuclear pores. Quantitative scanning transmission electron microscopy has estimated the mass of a nuclear pore noteworthy in that they saw: 1) the purification of both the yeast and vertebrate nuclear pores, 2

  6. LETTERS TO THE EDITOR RE: ``HOW MANY FOODBORNE OUTBREAKS OF SALMONELLA INFECTION OCCURRED IN

    E-Print Network [OSTI]

    Boehning, Dankmar

    LETTERS TO THE EDITOR RE: ``HOW MANY FOODBORNE OUTBREAKS OF SALMONELLA INFECTION OCCURRED IN FRANCE outbreaks of Salmonella infection that had oc- curred in France during the year 1995. The data provided), the Ministry of Agriculture (MA), and the National Salmonella and Shigella Reference Center (NRC). A complete

  7. Neutron Stimulated Emission Computed Tomography of Stable Isotopes

    E-Print Network [OSTI]

    on the development of a new molecular imaging technique using inelastic scattering of fast neutrons. Earlier studies characteristic gamma photons through inelastic scattering of an external neutron beam. These stable isotopes canNeutron Stimulated Emission Computed Tomography of Stable Isotopes Carey E. Floyd Jr.*ab , Calvin

  8. Use of Stable Isotopes in Forensic Analysis of Microorganisms

    SciTech Connect (OSTI)

    Kreuzer-Martin, Helen W.; Hegg, Eric L.

    2012-01-18

    The use of isotopic signatures for forensic analysis of biological materials is well-established, and the same general principles that apply to interpretation of stable isotope content of C, N, O, and H apply to the analysis of microorganisms. Heterotrophic microorganisms derive their isotopic content from their growth substrates, which are largely plant and animal products, and the water in their culture medium. Thus the isotope signatures of microbes are tied to their growth environment. The C, N, O, and H isotope ratios of spores have been demonstrated to constitute highly discriminating signatures for sample matching. They can rule out specific samples of media and/or water as possible production media, and can predict isotope ratio ranges of the culture media and water used to produce a given sample. These applications have been developed and tested through analyses of approximately 250 samples of Bacillus subtilis spores and over 500 samples of culture media, providing a strong statistical basis for data interpretation. A Bayesian statistical framework for integrating stable isotope data with other types of signatures derived from microorganisms has been able to characterize the culture medium used to produce spores of various Bacillus species, leveraging isotopic differences in different medium types and demonstrating the power of data integration for forensic investigations.

  9. Packed bed reactor for photochemical sup 196 Hg isotope separation

    SciTech Connect (OSTI)

    Grossman, M.W.; Speer, R.

    1992-03-03

    This patent describes a photochemical reactor useful for the isotopic enrichment of a predetermined isotope of mercury comprising a reactor cell and a monoisotopic light source It comprises: a plurality of transparent, straight reactor cell tubes disposed axially within the internal volume of the reactor cell to increase the surface area thereof for production deposition.

  10. Nitrogen isotope effects on glutamate decarboxylase from Escherichia coli

    SciTech Connect (OSTI)

    Abell, L.M.; O'Leary, M.H.

    1988-05-03

    The nitrogen isotope effect on the decarboxylation of glutamic acid by glutamate decarboxylase from Escherichia coli has been measured by comparison of the isotopic composition of the amino nitrogen of the product ..gamma..-aminobutyric acid isolated after 10-20% reaction with that of the starting glutamic acid. At pH 4.7, 37 /sup 0/C, the isotope effect is k/sup 14//k/sup 15/ = 0.9855 +/- 0.0006 when compared to unprotonated glutamic acid. Interpretation of this result requires knowledge of the equilibrium nitrogen isotope effect for Schiff base formation. This equilibrium isotope effect is K/sup 14//K/sup 15/ - 0.9824 for the formation of the unprotonated Schiff base between unprotonated valine and salicylaldehyde. Analysis of the nitrogen isotope effect on decarboxylation of glutamic acid and of the previously measured carbon isotope effect on this same reaction shows that decarboxylation and Schiff base formation are jointly rate limiting. The enzyme-bound Schiff base between glutamate and pyridoxal 5'-phosphate partitions approximately 2:1 between decarboxylation and return to the starting state. The nitrogen isotope effect also reveals that the Schiff base nitrogen is protonated in this intermediate.

  11. Lithium Isotope History of Cenozoic Seawater: Changes in Silicate Weathering

    E-Print Network [OSTI]

    Paytan, Adina

    Lithium Isotope History of Cenozoic Seawater: Changes in Silicate Weathering and Reverse Weathering 70 Ma · Overview of the Marine Lithium Cycle · Analytical Challenges · 68 Million Year Seawater Lithium Isotope Record (Forams) · Interpretation Standard: NIST L-SVEC Li (SRM 8545) #12;100 Ma Climate

  12. Tracking the lithium isotopic evolution of the mantle using carbonatites

    E-Print Network [OSTI]

    Mcdonough, William F.

    Tracking the lithium isotopic evolution of the mantle using carbonatites Ralf Halama a,, William F. © 2007 Elsevier B.V. All rights reserved. Keywords: lithium isotopes; carbonatites; mantle geochemistry 1. Introduction Lithium (Li) is an incompatible element that is typi- cally enriched 10 to 50-fold in crustal

  13. Sandia National Laboratories Medical Isotope Reactor concept.

    SciTech Connect (OSTI)

    Coats, Richard Lee; Dahl, James J.; Parma, Edward J., Jr.

    2010-04-01

    This report describes the Sandia National Laboratories Medical Isotope Reactor and hot cell facility concepts. The reactor proposed is designed to be capable of producing 100% of the U.S. demand for the medical isotope {sup 99}Mo. The concept is novel in that the fuel for the reactor and the targets for the {sup 99}Mo production are the same. There is no driver core required. The fuel pins that are in the reactor core are processed on a 7 to 21 day irradiation cycle. The fuel is low enriched uranium oxide enriched to less than 20% {sup 235}U. The fuel pins are approximately 1 cm in diameter and 30 to 40 cm in height, clad with Zircaloy (zirconium alloy). Approximately 90 to 150 fuel pins are arranged in the core in a water pool {approx}30 ft deep. The reactor power level is 1 to 2 MW. The reactor concept is a simple design that is passively safe and maintains negative reactivity coefficients. The total radionuclide inventory in the reactor core is minimized since the fuel/target pins are removed and processed after 7 to 21 days. The fuel fabrication, reactor design and operation, and {sup 99}Mo production processing use well-developed technologies that minimize the technological and licensing risks. There are no impediments that prevent this type of reactor, along with its collocated hot cell facility, from being designed, fabricated, and licensed today.

  14. Supported palladium materials for isotope separation

    SciTech Connect (OSTI)

    Rutherford, W.M.; Ellis, R.E.; Abell, G.C.

    1988-01-21

    Several palladium packing materials were investigated for their suitability for use in the separation of hydrogen isotopes by displacement chromatography. The materials included palladium on Chromosorb and several formulations of palladium on commercially available alpha-alumina-based catalyst supports. All materials showed some degradation upon being subjected to repeated hydriding-dehydriding cycles; however, the degradation did not lead to unacceptably low permeability to gas flow. Dynamic performance of the packings was evaluated by displacement of deuterium with protium at several temperatures and flow rates. Isotopic exchange was generally rapid. However, high surface area packings (greater than 4 m/sup 2//g) yielded transition zones that were initially sharp, but had long ''tails'' at deuterium concentrations below 5%. Best results were obtained with a packing containing 48.2% palladium on Norton catalyst support No. SA5*21 (surface area = 0.33 m/sup 2//g). Improved performance was observed as the displacement temperature was increased to 80/sup 0/C from 22/sup 0/C. The slight decrease in equilibrium separation was more than offset by improved kinetics at the higher temperature. 19 figs., 6 tabs.

  15. Preliminary Notice of Violation, MAC Isotopes, LLC - EA- 1998-05 |

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

    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 GasAdjustmentsShirleyEnergyTher i nAandSummary AreasDepartment of Energy 8 Issued to MAC Isotopes, LLC,

  16. High Flux Isotope Reactor system RELAP5 input model

    SciTech Connect (OSTI)

    Morris, D.G.; Wendel, M.W.

    1993-01-01

    A thermal-hydraulic computational model of the High Flux Isotope Reactor (HFIR) has been developed using the RELAP5 program. The purpose of the model is to provide a state-of-the art thermal-hydraulic simulation tool for analyzing selected hypothetical accident scenarios for a revised HFIR Safety Analysis Report (SAR). The model includes (1) a detailed representation of the reactor core and other vessel components, (2) three heat exchanger/pump cells, (3) pressurizing pumps and letdown valves, and (4) secondary coolant system (with less detail than the primary system). Data from HFIR operation, component tests, tests in facility mockups and the HFIR, HFIR specific experiments, and other pertinent experiments performed independent of HFIR were used to construct the model and validate it to the extent permitted by the data. The detailed version of the model has been used to simulate loss-of-coolant accidents (LOCAs), while the abbreviated version has been developed for the operational transients that allow use of a less detailed nodalization. Analysis of station blackout with core long-term decay heat removal via natural convection has been performed using the core and vessel portions of the detailed model.

  17. Process for recovery of daughter isotopes from a source material

    DOE Patents [OSTI]

    Tranter, Troy J.; Todd, Terry A.; Lewis, Leroy C.; Henscheid, Joseph P.

    2005-10-04

    The invention includes a method of separating isotopes from a mixture containing at least two isotopes in a solution. A first isotope is precipitated and is collected from the solution. A daughter isotope is generated and collected from the first isotope. The invention includes a method of producing an actinium-225/bismuth-213 product from a material containing thorium-229 and thorium-232. A solution is formed containing nitric acid and the material and iodate is added to form a thorium iodate precipitate. A supernatant is separated from the thorium iodate precipitate and a second volume of nitric acid is added to the precipitate. The precipitate is stored and a decay product comprising actinium-225 and bismuth-213 is generated in the second volume of nitric acid which is then separated from the thorium iodate precipitate, filtered, and treated using at least one chromatographic procedure. The invention also includes a system for producing an actinium-225/bismuth-213 product.

  18. Special isotope separation at the Idaho National Engineering Laboratory

    SciTech Connect (OSTI)

    Hendrickson, P.D.

    1989-02-03

    The SIS facilities will include a Plutonium Processing Facility (PPF), a Laser Support Facility (LSF), and all associated equipment required for isotope separation. The SIS Plant will process fuel-grade plutonium into weapons-grade plutonium using Atomic Vapor Laser Isotope Separation (AVLIS) and supporting chemical processes. The AVLIS process uses precisely tuned visible laser light to selectively ionize or excite specific plutonium isotopes in a vapor stream. The ionized plutonium isotopes (Pu 240, Pu 238 and Pu 241) are then separated from the plutonium isotope of interest (Pu 239). Chemical processes are required to (1) prepare the AVLIS plutonium feed for processing, remove americium-241, and cast plutonium metal into forms that meet AVLIS processing requirements; (2) recover and, if required, purify the AVLIS plutonium product; and (3) recover and process the AVLIS separated by-products. This presentation describes the production facility and some of the plutonium processes.

  19. Proton magnetic resonance studies of the chemical shifts occurring in propionic acid-dioxane solutions 

    E-Print Network [OSTI]

    Oldham, William J. Bryan

    1958-01-01

    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 0 ~ ~ ~ 35 LIET OF TABES TAEIR6 l, Chemical shiftsoccurring in aqueous solutions of propionic PAGE ac id ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 21 2, Chemical shifts occurring in propionic ac1d-dioxane solut1ons 22 3. C... is added. , the dimers break up to form monomers. There i, s formed alternately a hydrogen bond between the monomer ac1d and the water, forming a complex. If the correlation times of the diner state aud oomplex water state ere sufficiently smallv...

  20. Shell model description of Ge isotopes

    E-Print Network [OSTI]

    J. G. Hirsch; P. C. Srivastava

    2012-04-12

    A shell model study of the low energy region of the spectra in Ge isotopes for $38\\leq N\\leq 50$ is presented, analyzing the excitation energies, quadrupole moments, $B(E2)$ values and occupation numbers. The theoretical results have been compared with the available experimental data. The shell model calculations have been performed employing three different effective interactions and valence spaces.We have used two effective shell model interactions, JUN45 and jj44b, for the valence space $f_{5/2} \\, p \\,g_{9/2}$ without truncation. To include the proton subshell $f_{7/2}$ in valence space we have employed the $fpg$ effective interaction due to Sorlin {\\it et al.}, with $^{48}$Ca as a core and a truncation in the number of excited particles.

  1. Compact hydrogen/helium isotope mass spectrometer

    DOE Patents [OSTI]

    Funsten, Herbert O. (Los Alamos, NM); McComas, David J. (Los Alamos, NM); Scime, Earl E. (Morgantown, WV)

    1996-01-01

    The compact hydrogen and helium isotope mass spectrometer of the present invention combines low mass-resolution ion mass spectrometry and beam-foil interaction technology to unambiguously detect and quantify deuterium (D), tritium (T), hydrogen molecule (H.sub.2, HD, D.sub.2, HT, DT, and T.sub.2), .sup.3 He, and .sup.4 He concentrations and concentration variations. The spectrometer provides real-time, high sensitivity, and high accuracy measurements. Currently, no fieldable D or molecular speciation detectors exist. Furthermore, the present spectrometer has a significant advantage over traditional T detectors: no confusion of the measurements by other beta-emitters, and complete separation of atomic and molecular species of equivalent atomic mass (e.g., HD and .sup.3 He).

  2. Giant Quadrupole-Resonance in Ni Isotopes 

    E-Print Network [OSTI]

    Youngblood, David H.; Lui, YW; Garg, U.; Peterson, R. J.

    1992-01-01

    VOLUME 45, NUMBER 5 MAY 1992 Giant quadrupole resonance in Ni isotopes D. H. Youngblood and Y.-%. Lui Texas A&M UniUersity, College Station, Texas 77843 U. Garg University of Notre Dame, South Bend, Indiana 46556 R. J. Peterson University... (%) 58+12 76+14 78+14 90+16 Cp 0.80+0.04 0.84+0.04 0.82+0. 12 1.05+0. 10 2174 YOUNGBLOOD, LUI, GARG, AND PETERSON 45 1000 100 60Ni(n, n') E = 129 MeV 1 000 100 58Ni(n, n') 10 10 100 z' 1000 64Ni(n, n') 1OO~y 64 Ni 100 10 I s & & I...

  3. Chemical and isotopic determination from complex spectra

    SciTech Connect (OSTI)

    Zardecki, A.; Strittmatter, R.B.

    1995-07-01

    Challenges for proliferation detection include remote, high- sensitivity detection of chemical effluents from suspect facilities and enhanced detection sensitivity for nuclear material. Both the identification of chemical effluents with lidar and enhanced nuclear material detection from radiation sensors involve determining constituents from complex spectra. In this paper, we extend techniques used to analyze time series to the analysis of spectral data. Pattern identification methods are applied to spectral data for domains where standard matrix inversion may not be suitable because of detection statistics. We use a feed-forward, back-propagation neural network in which the nodes of the input layer are fed with the observed spectral data. The nodes of the output layer contain the identification and concentration of the isotope or chemical effluent the sensor is to identify. We will discuss the neural network architecture, together with preliminary results obtained from the training process.

  4. Laser-isotope-separation technology. [Review; economics

    SciTech Connect (OSTI)

    Jensen, R.J.; Blair, L.S.

    1981-01-01

    The Molecular Laser Isotope Separation (MLIS) process currently under development is discussed as an operative example of the use of lasers for material processing. The MLIS process, which uses infrared and ultraviolet lasers to process uranium hexafluoride (UF/sub 6/) resulting in enriched uranium fuel to be used in electrical-power-producing nuclear reactor, is reviewed. The economics of the MLIS enrichment process is compared with conventional enrichment technique, and the projected availability of MLIS enrichment capability is related to estimated demands for U.S. enrichment service. The lasers required in the Los Alamos MLIS program are discussed in detail, and their performance and operational characteristics are summarized. Finally, the timely development of low-cost, highly efficient ultraviolet and infrared lasers is shownd to be the critical element controlling the ultimate deployment of MLIS uranium enrichment. 8 figures, 7 tables.

  5. Temperature dependence of carbon isotope fractionation in CAM plants

    SciTech Connect (OSTI)

    Deleens, E.; Treichel, I.; O'Leary, M.H.

    1985-09-01

    The carbon isotope fractionation associated with nocturnal malic acid synthesis in Kalanchoe daigremontiana and Bryophyllum tubiflorum was calculated from the isotopic composition of carbon-4 of malic acid, after appropriate corrections. In the lowest temperature treatment (17/sup 0/C nights, 23/sup 0/C days), the isotope fractionation for both plants is -4% per thousand (that is, malate is enriched in /sup 13/C relative to the atmosphere). For K. daigremontiana, the isotope fractionation decreases with increasing temperature, becoming approximately 0% per thousand at 27/sup 0/C/33/sup 0/C. Detailed analysis of temperature effects on the isotope fractionation indicates that stomatal aperture decreases with increasing temperature and carboxylation capacity increases. For B. tubiflorum, the temperature dependence of the isotope fractionation is smaller and is principally attributed to the normal temperature dependences of the rates of diffusion and carboxylation steps. The small change in the isotopic composition of remaining malic acid in both species which is observed during deacidification indicates that malate release, rather than decarboxylation, is rate limiting in the deacidification process. 28 references, 1 figure, 4 tables.

  6. Hydrogen Isotope Exchange Properties of Porous Solids Containing Hydrogen

    SciTech Connect (OSTI)

    HEUNG, LEUNGK.

    2004-08-18

    Porous solids such as activated alumina, silica and molecular sieves generally contain significant amounts of hydrogen atoms in the form of H2O or OH even at high temperature and low humidity environment. A significant amount of this hydrogen is available for reversible isotopic exchange. This exchange reaction is slow under normal conditions and does not render itself to practical applications. But if the exchange kinetics is improved this reaction has the potential to be used for tritium removal from gas streams or for hydrogen isotopic separation.The use of catalysts to improve the exchange kinetics between hydrogen isotope in the gas phase and that in the solid phase was investigated. Granules of alumina, silica and molecular sieve were coated with platinum or palladium as the catalyst. The granules were packed in a 2-cm diameter column for isotope exchange tests. Gas streams containing different concentrations of deuterium in nitrogen or argon were fed through the protium saturated column. Isotope concentration in column effluent was monitored to generate isotope break-through curves. The curves were analyzed to produce information on the kinetics and capacity of the material. The results showed that all materials tested provided some extent of isotope exchange but some were superior both in kinetics and capacity. This paper will present the test results.

  7. Paleo-channel deposition of natural uranium at a US Air Force landfill

    SciTech Connect (OSTI)

    Young, Carl; Weismann, Joseph; Caputo, Daniel [Cabrera Services, Inc., East Hartford, Connecticut (United States)

    2007-07-01

    Available in abstract form only. Full text of publication follows: The US Air Force sought to identify the source of radionuclides that were detected in groundwater surrounding a closed solid waste landfill at the former Lowry Air Force Base in Denver, Colorado, USA. Gross alpha, gross beta, and uranium levels in groundwater were thought to exceed US drinking water standards and down-gradient concentrations exceeded up-gradient concentrations. Our study has concluded that the elevated radionuclide concentrations are due to naturally-occurring uranium in the regional watershed and that the uranium is being released from paleo-channel sediments beneath the site. Groundwater samples were collected from monitor wells, surface water and sediments over four consecutive quarters. A list of 23 radionuclides was developed for analysis based on historical landfill records. Concentrations of major ions and metals and standard geochemical parameters were analyzed. The only radionuclide found to be above regulatory standards was uranium. A search of regional records shows that uranium is abundant in the upstream drainage basin. Analysis of uranium isotopic ratios shows that the uranium has not been processed for enrichment nor is it depleted uranium. There is however slight enrichment in the U-234:U- 238 activity ratio, which is consistent with uranium that has undergone aqueous transport. Comparison of up-gradient versus down-gradient uranium concentrations in groundwater confirms that higher uranium concentrations are found in the down-gradient wells. The US drinking water standard of 30 {mu}g/L for uranium was exceeded in some of the up-gradient wells and in most of the down-gradient wells. Several lines of evidence indicate that natural uranium occurring in streams has been preferentially deposited in paleo-channel sediments beneath the site, and that the paleo-channel deposits are causing the increased uranium concentrations in down-gradient groundwater compared to up-gradient groundwater. (authors)

  8. A. Paytan and E.T. Gray Chapter 9 Sulfur Isotope Stratigraphy

    E-Print Network [OSTI]

    Paytan, Adina

    A. Paytan and E.T. Gray Chapter 9 Sulfur Isotope Stratigraphy Abstract: The sulfur isotopic.4. Measurement and Materials for Sulfur Isotope Stratigraphy 171 9.4.1. Isotope Analyses 171 9.4.2. Materials. The features in the record can also be used to correlate between stratigraphic sections and sequences

  9. Evolution of the geothermal fluids at Los Azufres, Mexico, as traced by noble gas isotopes, 18

    E-Print Network [OSTI]

    Evolution of the geothermal fluids at Los Azufres, Mexico, as traced by noble gas isotopes, 18 O, D: Noble gases Strontium isotopes Helium isotopes Geothermal energy Los Azufres Araró Mexico Isotopes of noble gases, CO2, H2O and Sr were measured in 10 geothermal wells and 8 hot springs, fumaroles and mud

  10. 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

  11. Coupled molybdenum, iron and uranium stable isotopes as oceanic paleoredox proxies during the Paleoproterozoic Shunga Event

    E-Print Network [OSTI]

    Coupled molybdenum, iron and uranium stable isotopes as oceanic paleoredox proxies during isotopes Uranium isotopes Iron isotopes Paleoproterozoic Euxinic The Paleoproterozoic Era was a time that the studied section was deposited under dominantly euxinic conditions (anoxic and sulfidic) and that the lower

  12. Standard practice for the ion exchange separation of uranium and plutonium prior to isotopic analysis

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    Standard practice for the ion exchange separation of uranium and plutonium prior to isotopic analysis

  13. Direct analysis of air filter samples for alpha emitting isotopes

    SciTech Connect (OSTI)

    Mohagheghi, A.H.; Ghanbari, F.; Ebara, S.B.; Enghauser, M.E. [Sandia National Labs., Albuquerque, NM (United States); Bakhtiar, S.N. [Westinghouse WIPP, Carlsbad, NM (United States)

    1997-04-01

    The traditional method for determination of alpha emitting isotopes on air filters has been to process the samples by radiochemical methods. However, this method is too slow for cases of incidents involving radioactive materials where the determination of personnel received dose is urgent. A method is developed to directly analyze the air filters taken from personal and area air monitors. The site knowledge is used in combination with alpha spectral information to identify isotopes. A mathematical function is developed to estimate the activity for each isotope. The strengths and weaknesses of the method are discussed.

  14. Method for isotopic analysis of chlorinated organic compounds

    DOE Patents [OSTI]

    Holt, B.D.; Sturchio, N.C.

    1999-08-24

    The present invention provides a method for preparing a VOC sample for carbon and chlorine isotope ratio analysis by mass spectrometer. A VOC sample is placed in a combustion tube and reacted with CuO to form CO{sub 2} and CuCl. The CO{sub 2} is then extracted and analyzed for the carbon isotope ratio. The CuCl is separated from the excess CuO and reacted with CH{sub 3}I to form CH{sub 3}Cl, extracted and analyzed for chlorine isotope ratio. 9 figs.

  15. Isotope and Nuclear Chemistry Division annual report, FY 1983

    SciTech Connect (OSTI)

    Heiken, J.H.; Lindberg, H.A. (eds.)

    1984-05-01

    This report describes progress in the major research and development programs carried out in FY 1983 by the Isotope and Nuclear Chemistry Division. It covers radiochemical diagnostics of weapons tests; weapons radiochemical diagnostics research and development; other unclassified weapons research; stable and radioactive isotope production, separation, and applications (including biomedical applications); element and isotope transport and fixation; actinide and transition metal chemistry; structural chemistry, spectroscopy, and applications; nuclear structure and reactions; irradiation facilities; advanced analytical techniques; development and applications; atmospheric chemistry and transport; and earth and planetary processes.

  16. Cost Estimate for Laser Isotope Separation for RIA

    SciTech Connect (OSTI)

    Scheibner, K

    2004-11-01

    Isotope enrichment of some elements is required in support of the Rare Isotope Accelerator (RIA) in order to obtain the beam intensities, source efficiencies and/or source lifetime required by RIA. The economics of using Atomic Vapor Laser Isotope Separation (AVLIS) technology as well as ElectroMagnetic (EM) separation technology has been evaluated. It is concluded that such an AVLIS would be about 10 times less expensive than a facility based on electromagnetic separation - $17 M versus $170 M. In addition, the AVLIS facility footprint would be about 10 times smaller, and operations would require about 4 years (including 2 years of startup) versus about 11 years for an EM facility.

  17. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO sub 2 catalysts

    SciTech Connect (OSTI)

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  18. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO{sub 2} catalysts

    SciTech Connect (OSTI)

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  19. The CNO Isotopes: Deep Circulation in Red Giants and First and Second Dredge-up

    E-Print Network [OSTI]

    Arnold I. Boothroyd; I. -Juliana Sackmann

    1998-06-16

    It is demonstrated that deep circulation mixing below the base of the standard convective envelope, and the consequent "cool bottom processing" (CBP) of the CNO isotopes, can reproduce the trend with stellar mass of the C-12/C-13 observations in low mass red giants. (This trend is opposite to what is expected from standard first dredge-up.) Our models assume that extra mixing always reaches to the same distance in temperature from the H-burning shell, and that CBP begins when the H-burning shell erases the molecular weight discontinuity ("mu-barrier") established by first dredge-up. For Pop I stars, none of the other CNO isotopes except N-15 are expected to be altered by CBP. (If O-18 depletion occurs on the AGB, as some observations suggest, it would require that extra mixing reach closer to the H-burning shell on the AGB than on the RGB --- and should also result in a much lower C-12/C-13 ratio than is observed.) CBP increases as one reduces the stellar mass or metallicity --- roughly as 1/M^2 on the RGB, due to the longer RGB of low mass stars, and as 1/Z, due to higher H-shell burning temperatures at low metallicity. In low mass Pop II stars, all the CNO isotopes are expected to be altered by CBP. Field Pop II stars exhibit RGB abundances consistent with the predictions of our CBP models that have been normalized to reproduce the Pop I RGB abundances, but globular cluster stars are observed to encounter much more extensive processing; also, CBP is observed to start near the base of the globular cluster RGB (overcoming any "mu-barrier"). Standard first and second dredge-up are also presented, and enrichment of the interstellar medium, relative to SN. For light elements, see astro-ph/9512122.

  20. Natural Gas

    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) Wyoming963Residential2, 2014ProvedYear Jan Feb MarNGPL Production,Energy Office

  1. Multiple-sulfur isotope effects during photolysis of carbonyl sulfide

    E-Print Network [OSTI]

    Lin, Ying

    Laboratory experiments were carried out to determine sulfur isotope effects during ultraviolet photolysis of carbonyl sulfide (OCS) to carbon monoxide (CO) and elemental sulfur (S[superscript 0]). The OCS gas at 3.7 to 501 ...

  2. The HIgh Flux Isotope Reactor: Past, Present, and Future

    SciTech Connect (OSTI)

    Beierschmitt, Kelly J [ORNL; Farrar, Mike B [ORNL

    2009-01-01

    HFIR construction began in 1965 and completed in 1966. During the first 15 years of operation, the heavy actinide isotope production mission was dominant. HFIR is now positioned as one of the most versataile research reactors in the world.

  3. Process for exchanging hydrogen isotopes between gaseous hydrogen and water

    DOE Patents [OSTI]

    Hindin, Saul G. (Mendham, NJ); Roberts, George W. (Westfield, NJ)

    1980-08-12

    A process for exchanging isotopes of hydrogen, particularly tritium, between gaseous hydrogen and water is provided whereby gaseous hydrogen depeleted in tritium and liquid or gaseous water containing tritium are reacted in the presence of a metallic catalyst.

  4. AN ISOTOPE HYDROLOGY STUDY OF THE KILAUEA VOLCANO AREA, HAWAII

    E-Print Network [OSTI]

    AN ISOTOPE HYDROLOGY STUDY OF THE KILAUEA VOLCANO AREA, HAWAII STUDY OF THE KILAUEA VOLCANO AREA, HAWAII M.A. Scholl, S.E. Ingebritsen, C.J. Janik, and J.P. Kauahikaua

  5. Carbon stable isotopes suggest that hippopotamus-vectored nutrients subsidize

    E-Print Network [OSTI]

    Lewison, Rebecca

    Carbon stable isotopes suggest that hippopotamus-vectored nutrients subsidize aquatic consumers that hippopotamus-vectored nutrients subsidize aquatic consumers in an East African river. Ecosphere 6(4):52. http

  6. A Strontium Isotopic Study Of Newberry Volcano, Central Oregon...

    Open Energy Info (EERE)

    content with 87Sr86Sr suggests that some isotopic ratios reflect shallow crustal contamination, but the data also suggest that two mantle sources, a prominent one at 0.7036 and...

  7. The marine geochemistry of iron and iron isotopes

    E-Print Network [OSTI]

    Bergquist, Bridget A., 1973-

    2004-01-01

    This thesis addressed questions about the Fe cycle by measuring detailed profiles and transects of Fe species in the ocean and also by exploring the use of a new tracer of Fe, Fe isotopic fractionation. In the subtropical ...

  8. Extraction of -cellulose from mummified wood for stable isotopic analysis

    E-Print Network [OSTI]

    Gedalof, Ze'ev

    Extraction of -cellulose from mummified wood for stable isotopic analysis Benjamin A. Hook a cellulose can provide valuable paleocli- matic information at annual and subannual resolution, from time the trees grew. In the mummified wood, polysaccharides (hemicellulose, -cellulose) are frequently

  9. 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...

  10. Global isotopic signatures of oceanic island basalts / by

    E-Print Network [OSTI]

    Oschmann, Lynn A

    1991-01-01

    Sr, Nd and Pb isotopic analyses of 477 samples representing 30 islands or island groups, 3 seamounts or seamount chains, 2 oceanic ridges and 1 oceanic plateau [for a total of 36 geographic features] are compiled to form ...

  11. Surface-cycling of rhenium and its isotopes

    E-Print Network [OSTI]

    Miller, Christian Alexander

    2009-01-01

    The application of elemental and isotopic metal palaeoredox tracers to the geologic past rests on an understanding of modern metal cycles. This study reevaluates the surface-cycling of Mo and Re in near-surface reservoirs. ...

  12. RESOLUTION OF URANIUM ISOTOPES WITH KINETIC PHOSPHORESCENCE ANALYSIS

    SciTech Connect (OSTI)

    Miley, Sarah M.; Hylden, Anne T.; Friese, Judah I.

    2013-04-01

    This study was conducted to test the ability of the Chemchek™ Kinetic Phosphorescence Analyzer Model KPA-11 with an auto-sampler to resolve the difference in phosphorescent decay rates of several different uranium isotopes, and therefore identify the uranium isotope ratios present in a sample. Kinetic phosphorescence analysis (KPA) is a technique that provides rapid, accurate, and precise determination of uranium concentration in aqueous solutions. Utilizing a pulsed-laser source to excite an aqueous solution of uranium, this technique measures the phosphorescent emission intensity over time to determine the phosphorescence decay profile. The phosphorescence intensity at the onset of decay is proportional to the uranium concentration in the sample. Calibration with uranium standards results in the accurate determination of actual concentration of the sample. Different isotopes of uranium, however, have unique properties which should result in different phosphorescence decay rates seen via KPA. Results show that a KPA is capable of resolving uranium isotopes.

  13. The isotopic composition of plant and soil biomarkers of pollution

    E-Print Network [OSTI]

    Randerson, JT; Pataki, DE; Wang, W; Herzenach, M; Grulke, NE

    2010-01-01

    these isotopes are “decoupled”. Wankel et al. (2006) studied15:1301–1346 Kendall C, Elliott EM, Wankel SD (2007) Tracingmapping. Springer, Berlin Wankel SD, Kendall C, Francis CA,

  14. Delayed neutron energy spectrum measurements of actinide waste isotopes 

    E-Print Network [OSTI]

    Comfort, Christopher M.

    1998-01-01

    was irradiated using the Texas A&M Nuclear Science Center Reactor (NSCR). Three proton recoil detectors, operating individually, in conjunction with MCNP calculated response functions, were used to measure the delayed neutron energy spectra of each isotope...

  15. Evidence of magnetic isotope effects during thermochemical sulfate reduction

    E-Print Network [OSTI]

    Oduro, Harry D.

    Thermochemical sulfate reduction experiments with simple amino acid and dilute concentrations of sulfate reveal significant degrees of mass-independent sulfur isotope fractionation. Enrichments of up to 13‰ for [superscript ...

  16. Uranium accountancy in Atomic Vapor Laser Isotope Separation

    SciTech Connect (OSTI)

    Carver, R.D.

    1986-01-01

    The AVLIS program pioneers the large scale industrial application of lasers to produce low cost enriched uranium fuel for light water reactors. In the process developed at Lawrence Livermore National Laboratory, normal uranium is vaporized by an electron beam, and a precisely tuned laser beam selectively photo-ionizes the uranium-235 isotopes. These ions are moved in an electromagnetic field to be condensed on the product collector. All other uranium isotopes remain uncharged and pass through the collector section to condense as tails. Tracking the three types of uranium through the process presents special problems in accountancy. After demonstration runs, the uranium on the collector was analyzed for isotopic content by Battelle Pacific Northwest Laboratory. Their results were checked at LLNL by analysis of parallel samples. The differences in isotopic composition as reported by the two laboratories were not significant.

  17. FY09 PROGRESS: MULTI-ISOTOPE PROCESS (MIP) MONITOR

    SciTech Connect (OSTI)

    Schwantes, Jon M.; Orton, Christopher R.; Fraga, Carlos G.; Christensen, Richard; Laspe, Amy R.; Ward, Rebecca M.

    2009-10-18

    Model and experimental estimates of the Multi-Isotope Process Monitor performance for determining burnup after dissolution and acid concentration during solvent extraction steps during reprocessing of spent nuclear fuel are presented.

  18. Chemical and Isotopic Composition of Casa Diablo Hot Spring:...

    Open Energy Info (EERE)

    Chemical and Isotopic Composition of Casa Diablo Hot Spring: Magmatic CO2 near Mammoth Lakes, CA Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  19. Strontium isotope quantification of siderite, brine and acid mine drainage contributions to abandoned gas well discharges in the Appalachian Plateau

    SciTech Connect (OSTI)

    Chapman, Elizabeth C.; Capo, Rosemary C.; Stewart, Brian W.; Hedin, Robert S.; Weaver, Theodore J.; Edenborn, Harry M.

    2013-04-01

    Unplugged abandoned oil and gas wells in the Appalachian region can serve as conduits for the movement of waters impacted by fossil fuel extraction. Strontium isotope and geochemical analysis indicate that artesian discharges of water with high total dissolved solids (TDS) from a series of gas wells in western Pennsylvania result from the infiltration of acidic, low Fe (Fe < 10 mg/L) coal mine drainage (AMD) into shallow, siderite (iron carbonate)-cemented sandstone aquifers. The acidity from the AMD promotes dissolution of the carbonate, and metal- and sulfate-contaminated waters rise to the surface through compromised abandoned gas well casings. Strontium isotope mixing models suggest that neither upward migration of oil and gas brines from Devonian reservoirs associated with the wells nor dissolution of abundant nodular siderite present in the mine spoil through which recharge water percolates contribute significantly to the artesian gas well discharges. Natural Sr isotope composition can be a sensitive tool in the characterization of complex groundwater interactions and can be used to distinguish between inputs from deep and shallow contamination sources, as well as between groundwater and mineralogically similar but stratigraphically distinct rock units. This is of particular relevance to regions such as the Appalachian Basin, where a legacy of coal, oil and gas exploration is coupled with ongoing and future natural gas drilling into deep reservoirs.

  20. Low-temperature chemistry between water and hydroxyl radicals: H/D isotopic effects

    E-Print Network [OSTI]

    Lamberts, T; Puletti, F; Ioppolo, S; Cuppen, H M; Linnartz, H

    2015-01-01

    Sets of systematic laboratory experiments are presented -- combining Ultra High Vacuum cryogenic and plasma-line deposition techniques -- that allow us to compare H/D isotopic effects in the reaction of H2O (D2O) ice with the hydroxyl radical OD (OH). The latter is known to play a key role as intermediate species in the solid-state formation of water on icy grains in space. The main finding of our work is that the reaction H2O + OD --> OH + HDO occurs and that this may affect the HDO/H2O abundances in space. The opposite reaction D2O + OH --> OD + HDO is much less effective, and also given the lower D2O abundances in space not expected to be of astronomical relevance. The experimental results are extended to the other four possible reactions between hydroxyl and water isotopes and are subsequently used as input for Kinetic Monte Carlo simulations. This way we interpret our findings in an astronomical context, qualitatively testing the influence of the reaction rates.

  1. Isotopic Anomalies in CP Stars: Helium, Mercury, Platinum, and Calcium

    E-Print Network [OSTI]

    C. R. Cowley; S. Hubrig; F. Castelli

    2007-11-15

    We review the classical observational results for isotopic abundance variations for several elements in CP stars. We concentrate on the "newest" anomaly, in calcium. The cosmically very rare isotope, Ca-48 can rival and even dominate the more common, alpha nuclide, Ca-40. Relevant examples are found in the hot, non-magnetic HgMn stars, and the field horizontal-branch star, Feige 86. The calcium anomaly is also present in cool, magnetic stars, including the notorious HD 101065, Przybylski's star.

  2. Separation of the isotopes of boron by chemical exchange reactions

    DOE Patents [OSTI]

    McCandless, Frank P. (Bozeman, MT); Herbst, Ronald S. (Idaho Falls, ID)

    1995-01-01

    The isotopes of boron, .sup.10 B and .sup.11 B, are separated by means of a gas-liquid chemical exchange reaction involving the isotopic equilibrium between gaseous BF.sub.3 and a liquid BF.sub.3 . donor molecular addition complex formed between BF.sub.3 gas and a donor chosen from the group consisting of: nitromethane, acetone, methyl isobutyl ketone, or diisobutyl ketone.

  3. Configuration mixing effects in neutron-rich carbon isotopes

    E-Print Network [OSTI]

    C. X. Yuan; F. R. Xu; C. Qi

    2015-07-24

    Shell model calculations are done to study the structure of neutron-rich carbon isotopes. For both even-A and odd-A neutron-rich carbon isotopes, the energy levels are strongly affected by the configuration mixing of valence neutrons. The calculated energy levels in the nucleus $^{17}$C are significantly improved compared with experimental values when the model space of the three valence neutrons is enlarged from pure $\

  4. Configuration mixing effects in neutron-rich carbon isotopes

    E-Print Network [OSTI]

    Yuan, C X; Qi, C

    2015-01-01

    Shell model calculations are done to study the structure of neutron-rich carbon isotopes. For both even-A and odd-A neutron-rich carbon isotopes, the energy levels are strongly affected by the configuration mixing of valence neutrons. The calculated energy levels in the nucleus $^{17}$C are significantly improved compared with experimental values when the model space of the three valence neutrons is enlarged from pure $\

  5. Measurement of zinc stable isotope ratios in biogeochemical matrices by double-spike MC-ICPMS and determination of the isotope ratio pool available for plants from soil

    E-Print Network [OSTI]

    2010-01-01

    of the isotope ratio pool available for plants from soil Timto characterize the Zn isotope pool available to plants in athe composition of the Zn pool available to the plants [21,

  6. Determination of the origin of elevated uranium at a Former Air Force Landfill using non-parametric statistics analysis and uranium isotope ratio analysis

    SciTech Connect (OSTI)

    Weismann, J.; Young, C.; Masciulli, S.; Caputo, D.

    2007-07-01

    Lowry Air Force Base (Lowry) was closed in September 1994 as part of the Base Realignment and Closure (BRAC) program and the base was transferred to the Lowry Redevelopment Authority in 1995. As part of the due diligence activities conducted by the Air Force, a series of remedial investigations were conducted across the base. A closed waste landfill, designated Operable Unit 2 (OU 2), was initially assessed in a 1990 Remedial Investigation (RI; [1]). A Supplemental Remedial Investigation was conducted in 1995 [2] and additional studies were conducted in a 1998 Focused Feasibility Study. [3] The three studies indicated that gross alpha, gross beta, and uranium concentrations were consistently above regulatory standards and that there were detections of low concentrations other radionuclides. Results from previous investigations at OU 2 have shown elevated gross alpha, gross beta, and uranium concentrations in groundwater, surface water, and sediments. The US Air Force has sought to understand the provenance of these radionuclides in order to determine if they could be due to leachates from buried radioactive materials within the landfill or whether they are naturally-occurring. The Air Force and regulators agreed to use a one-year monitoring and sampling program to seek to explain the origins of the radionuclides. Over the course of the one-year program, dissolved uranium levels greater than the 30 {mu}g/L Maximum Contaminant Level (MCL) were consistently found in both up-gradient and down-gradient wells at OU 2. Elevated Gross Alpha and Gross Beta measurements that were observed during prior investigations and confirmed during the LTM were found to correlate with high dissolved uranium content in groundwater. If Gross Alpha values are corrected to exclude uranium and radon contributions in accordance with US EPA guidance, then the 15 pCi/L gross alpha level is not exceeded. The large dataset also allowed development of gross alpha to total uranium correlation factors so that gross alpha action levels can be applied to future long-term landfill monitoring to track radiological conditions at lower cost. Ratios of isotopic uranium results were calculated to test whether the elevated uranium displayed signatures indicative of military use. Results of all ratio testing strongly supports the conclusion that the uranium found in groundwater, surface water, and sediment at OU 2 is naturally-occurring and has not undergone anthropogenic enrichment or processing. U-234:U-238 ratios also show that a disequilibrium state, i.e., ratio greater than 1, exists throughout OU 2 which is indicative of long-term aqueous transport in aged aquifers. These results all support the conclusion that the elevated uranium observed at OU 2 is due to the high concentrations in the regional watershed. Based on the results of this monitoring program, we concluded that the elevated uranium concentrations measured in OU 2 groundwater, surface water, and sediment are due to the naturally-occurring uranium content of the regional watershed and are not the result of waste burials in the former landfill. Several lines of evidence indicate that natural uranium has been naturally concentrated beneath OU 2 in the geologic past and the higher of uranium concentrations in down-gradient wells is the result of geochemical processes and not the result of a uranium ore disposal. These results therefore provide the data necessary to support radiological closure of OU 2. (authors)

  7. Thermoacoustic natural gas liquefier

    SciTech Connect (OSTI)

    Swift, G.W.

    1997-05-01

    Cryenco and Los Alamos are collaborating to develop a natural-gas-powered natural-gas liquefier that will have no moving parts and require no electrical power. It will have useful efficiency, remarkable reliability, and low cost. The liquefaction of natural gas, which occurs at only 115 Kelvin at atmospheric pressure, has previously required rather sophisticated refrigeration machinery. The 1990 invention of the thermoacoustically driven orifice pulse-tube refrigerator (TA-DOPTR) provides cryogenic refrigeration with no moving parts for the first time. In short, this invention uses acoustic phenomena to produce refrigeration from heat. The required apparatus consists of nothing more than helium-filled heat exchangers and pipes, made of common materials, without exacting tolerances. In the Cryenco-Los Alamos collaboration, the authors are developing a version of this invention suitable for use in the natural-gas industry. The project is known as acoustic liquefier for short. The present program plans call for a two-phase development. Phase 1, with capacity of 500 gallon per day (i.e., approximately 40,000 scfd, requiring a refrigeration power of about 7 kW), is large enough to illuminate all the issues of large-scale acoustic liquefaction without undue cost, and to demonstrate the liquefaction of 60--70% of input gas, while burning 30--40%. Phase 2 will target versions of approximately 10{sup 6} scfd = 10,000 gallon per day capacity. In parallel with both, they continue fundamental research on the technology, directed toward increased efficiency, to build scientific foundations and a patent portfolio for future acoustic liquefiers.

  8. Proton radii of Be, B, and C isotopes

    E-Print Network [OSTI]

    Yoshiko Kanada-En'yo

    2014-11-04

    We investigate the neutron number $(N)$ dependence of root mean square radii of point proton distribution (proton radii) of Be, B, and C isotopes with the theoretical method of variation after spin-parity projection in the framework of antisymmetrized molecular dynamics (AMD). The proton radii in Be and B isotopes changes rapidly as $N$ increases, reflecting the cluster structure change along the isotope chains, whereas, those in C isotopes show a weak $N$ dependence because of the stable proton structure in nuclei with $Z=6$. In neutron-rich Be and B isotopes, the proton radii are remarkably increased by the enhancement of the two-center cluster structure in the prolately deformed neutron structure. We compare the $N$ dependence of the calculated proton radii with the experimental ones reduced from the charge radii determined by isotope shift and those deduced from the charge changing interaction cross section. It is found that the $N$ dependence of proton radii can be a probe to clarify enhancement and weakening of cluster structures.

  9. NEWS & VIEWS nature physics | VOL 2 | JULY 2006 | www.nature.com/naturephysics 445

    E-Print Network [OSTI]

    Loss, Daniel

    . In tokamak-based fusion plasmas, reconnection occurs as a result of plasma instabilities and hampers magnetic confinement. It influences the dayside dynamics of the Earth's magnetosphere and the magnetic substormsNEWS & VIEWS nature physics | VOL 2 | JULY 2006 | www.nature.com/naturephysics 445 MAGNETIC

  10. Natural gas monthly, February 1998

    SciTech Connect (OSTI)

    NONE

    1998-02-01

    This issue of the Natural Gas Monthly (NGM) presents the most recent estimates of natural gas data from the Energy Information Administration. Estimates extend through February 1998 for many data series, and through November 1997 for most natural gas prices. Highlights of the natural gas data contained in this issue are: Preliminary estimates for January and February 1998 show that dry natural gas production, net imports, and consumption are all within 1 percent of their levels in 1997. Warmer-than-normal weather in recent months has resulted in lower consumption of natural gas by the residential sector and lower net withdrawals of gas from under round storage facilities compared with a year ago. This has resulted in an estimate of the amount of working gas in storage at the end of February 1998 that is 18 percent higher than in February 1997. The national average natural gas wellhead price is estimated to be $3.05 per thousand cubic feet in November 1997, 7 percent higher than in October. The cumulative average wellhead price for January through November 1997 is estimated to be $2.42 per thousand cubic feet, 17 percent above that of the same period in 1996. This price increase is far less than 36-percent rise that occurred between 1995 and 1996. 6 figs., 26 tabs.

  11. Lithium isotopic systematics of A-type granites and their mafic enclaves: Further constraints on the Li isotopic composition of the continental crust

    E-Print Network [OSTI]

    Mcdonough, William F.

    Lithium isotopic systematics of A-type granites and their mafic enclaves: Further constraints form 6 February 2009 Accepted 15 February 2009 Editor: D.B. Dingwell Keywords: Lithium isotopes A-type granite Mafic enclave Continental crust Lithium concentrations and isotopic compositions of 39 A

  12. The Atomic Vapor Laser Isotope Separation Program

    SciTech Connect (OSTI)

    Not Available

    1992-11-09

    This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management`s position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted.

  13. Laser separation of uranium chosen for scaleup. [Atomic vapor laser isotope separation, molecular laser isotope separation, and plasma separation process

    SciTech Connect (OSTI)

    Rawls, R.L.

    1982-05-17

    Atomic vapor laser isotope separation (AVLIS) has been selected by the Department of Energy to go into large-scale engineering development and demonstration over two other advanced technologies, molecular laser isotope separation and plasma separation. DOE will continue to support development of another uranium enrichment technology, gas centrifugation. By or around 1990, the most promising gas centrifuge technique will be compared to the further developed AVLIS process, and a selection will be made between the two to replace the current technology, gaseous diffusion. The AVLIS process, plasma separation, and molecular laser isotope separation use the elective absorption of radiation of a particular energy level by the /sup 235/U isotope. The plasma separation process selectively energizes /sup 235/U by ion cyclotron resonance. The AVLIS and molecular laser isotope separation processes both use a carefully tuned laser to excite /sup 235/U isotope selectively. In the AVLIS process, uranium metal feed material is melted and vaporized to form an atomic uranium vapor stream. When this vapor stream passes through the beam of copper vapor lasers, the /sup 235/U atoms absorb the light and become ionized. These ionized atoms are collected by electromagnetic fields while the neutral /sup 238/U atoms pass through the magnetic field and are collected as tailings. The AVLIS process has the potential for significantly reducing the cost of enriching uranium. The status of dvelopment, cost, advantages and drawbacks of the five processes, (gaseous diffusion, gas centrifugation, AVLIS, molecular laser separation, plasma separation) are discussed. (ATT)

  14. Laser separation of uranium chosen for scaleup. [Atomic vapor laser isotope separation, molecular laser isotope separation plasma separation process

    SciTech Connect (OSTI)

    Rawls, R.L.

    1982-05-17

    Atomic vapor laser isotope separation (AVLIS) has been selected by the Department of Energy to go into large-scale engineering development and demonstration over two other advanced technologies, molecular laser isotope separation and plasma separation. DOE will continue to support development of another uranium enrichment technology, gas centrifugation. By or around 1990, the most promising gas centrifuge technique will be compared to the further developed AVLIS process, and a selection will be made between the two to replace the current technology, gaseous diffusion. The AVLIS process, plasma separation, and molecular laser isotope separation use the selective absorption of radiation of a particular energy level by the /sup 235/U isotope. The plasma separation process selectively energizes /sup 235/U by ion cyclotron resonance. The AVLIS and molecular laser isotope separation processes both use a carefully tuned laser to excite /sup 235/U isotope selectively. In the AVLIS process, uranium metal feed material is melted and vaporized to from an atomic uranium vapor stream. When this vapor stream passes through the beam of copper vapor lasers, the /sup 235/U atoms absorb the light and become ionized. These ionized atoms are collected by electromagnetic fields while the neutral /sup 238/U atoms pass through the magnetic field and are collected as tailings. The AVLIS process has the potential for significantly reducing the cost of enriching uranium. The status of development, cost, advantages and drawbacks of the five processes (gaseous diffusion, gas centrifugation, AVLIS, molecular laser separation, plasma separation) are discussed. (ATT)

  15. Elucidation of the Local and Long-Range Structural Changes that Occur in

    Office of Scientific and Technical Information (OSTI)

    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 NaturalDukeWakefieldSulfate Reducing(Journal Article) | SciTech(Journal Article)at theReport) |in QCD: Thethe Utilization

  16. NUCLEOSYNTHETIC TUNGSTEN ISOTOPE ANOMALIES IN ACID LEACHATES OF THE MURCHISON CHONDRITE: IMPLICATIONS FOR HAFNIUM-TUNGSTEN CHRONOMETRY

    SciTech Connect (OSTI)

    Burkhardt, Christoph; Wieler, Rainer; Kleine, Thorsten; Dauphas, Nicolas

    2012-07-01

    Progressive dissolution of the Murchison carbonaceous chondrite with acids of increasing strengths reveals large internal W isotope variations that reflect a heterogeneous distribution of s- and r-process W isotopes among the components of primitive chondrites. At least two distinct carriers of nucleosynthetic W isotope anomalies must be present, which were produced in different nucleosynthetic environments. The co-variation of {sup 182}W/{sup 184}W and {sup 183}W/{sup 184}W in the leachates follows a linear trend that is consistent with a mixing line between terrestrial W and a presumed s-process-enriched component. The composition of the s-enriched component agrees reasonably well with that predicted by the stellar model of s-process nucleosynthesis. The co-variation of {sup 182}W/{sup 184}W and {sup 183}W/{sup 184}W in the leachates provides a means for correcting the measured {sup 182}W/{sup 184}W and {sup 182}W/{sup 183}W of Ca-Al-rich inclusions (CAI) for nucleosynthetic anomalies using the isotopic variations in {sup 183}W/{sup 184}W. This new correction procedure is different from that used previously, and results in a downward shift of the initial {epsilon}{sup 182}W of CAI to -3.51 {+-} 0.10 (where {epsilon}{sup 182}W is the variation in 0.01% of the {sup 182}W/{sup 183}W ratio relative to Earth's mantle). This revision leads to Hf-W model ages of core formation in iron meteorite parent bodies that are {approx}2 Myr younger than previously calculated. The revised Hf-W model ages are consistent with CAI being the oldest solids formed in the solar system, and indicate that core formation in some planetesimals occurred within {approx}2 Myr of the beginning of the solar system.

  17. Natural Dynamics for Combinatorial Optimization

    E-Print Network [OSTI]

    Ovchinnikov, Igor V

    2015-01-01

    Stochastic and or natural dynamical systems (DSs) are dominated by sudden nonlinear processes such as neuroavalanches, gamma-ray bursts, solar flares, earthquakes etc. that exhibit scale-free statistics. These behaviors also occur in many nanosystems. On phase diagrams, these DSs belong to a finite-width phase that separates the phases of thermodynamic equilibrium and ordinary chaotic dynamics, and that is known under such names as intermittency, noise-induced chaos, and self-organized criticality. Within the recently formulated approximation-free cohomological theory of stochastic differential equations, the noise-induced chaos can be roughly interpreted as a noise-induced overlap between regular (integrable) and chaotic (non-integrable) deterministic dynamics so that DSs in this phase inherit the properties of the both. Here, we analyze this unique set of properties and conclude that such DSs must be the most efficient natural optimizers. Based on this understanding, we propose the method of the natural dyn...

  18. Isotope Ratio Triangulation: A Method for Determining Uranium Isotope Ratios and Application to the Search for Uranium Isotope Anomalies in the Mineral Titanite 

    E-Print Network [OSTI]

    Hill, Joseph Roger

    2014-11-10

    The U-Pb dating methods used in many geochronology laboratories take advantage of a mixed 235U-233U spike for precise uranium isotopic measurements and current data reduction algorithms assume a uniform 238U/235U value of 137.88. Recent re...

  19. ,"Natural Gas Consumption",,,"Natural Gas Expenditures"

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

    Census Division, 1999" ,"Natural Gas Consumption",,,"Natural Gas Expenditures" ,"per Building (thousand cubic feet)","per Square Foot (cubic feet)","per Worker (thousand cubic...

  20. A Naturally Occurring Mutation in ropB Suppresses SpeB Expression and Reduces M1T1 Group A Streptococcal

    E-Print Network [OSTI]

    Nizet, Victor

    University, Cairo, Egypt, 3 The VA Hospital, Memphis, Tennessee, United States of America, 4 The Department Epidemiological studies of group A streptococcus (GAS) have noted an inverse relationship between SpeB expression show that an intact RopB and efficient SpeB production are necessary for systemic infection with GAS

  1. A selective survey to determine the frequency of naturally occurring Hepatozoon canis infections in the Coastal Bend area of South Texas 

    E-Print Network [OSTI]

    Espitia, Noberto Francisco

    1985-01-01

    data applicable to the determination of prevalence rates of the disease and to construct patient profiles of the affected population. The investigation centered on the results of blood sample evaluations of seventy-five dogs collected among five... veterinary clinics during a sixty day period. Only client-owned animals visiting one of the five veterinary clinics on a scheduled working day were sampled. Clinical evaluations of blood samples included complete blood counts, differential white cell...

  2. Examining the stability of thermally fissile Th and U isotopes

    E-Print Network [OSTI]

    Bharat Kumar; S. K. Biswal; S. K. Singh; S. K. Patra

    2015-08-03

    The properties of recently predicted thermally fissile Th and U isotopes are studied within the framework of relativistic mean field (RMF) approach using axially deformed basis. We calculated the ground, first intrinsic excited state and matter density for highly neutron-rich thorium and uranium isotopes. The possible modes of decay like $\\alpha$-decay and $\\beta$-decay are analyzed. We found that the neutron-rich isotopes are stable against $\\alpha$-decay, however they are very much unstable against $\\beta$-decay. The life time of these nuclei predicted to be tens of second against $\\beta$-decay. If these nuclei utilize before their decay time, a lots of energy can be produced within the help of multi-fragmentation fission. Also, these nuclei have a great implication in astrophysical point of view. The total nucleonic densities distribution are calculated, from which the clusters inside the parent nuclei are determined. %Most of the thorium isotopes are $\\alpha$ emitters, where as some %of them have short half-lives. In some cases, we found the isomeric states with energy range from 2 to 3 MeV and three minima in the potential energy surface of $^{228-230}$Th and $^{228-234}$U isotopes.

  3. System for recovery of daughter isotopes from a source material

    DOE Patents [OSTI]

    Tranter, Troy J. (Idaho Falls, ID) [Idaho Falls, ID; Todd, Terry A. (Aberdeen, ID) [Aberdeen, ID; Lewis, Leroy C. (Idaho Falls, ID) [Idaho Falls, ID; Henscheid, Joseph P. (Idaho Falls, ID) [Idaho Falls, ID

    2009-08-04

    A method of separating isotopes from a mixture containing at least two isotopes in a solution is disclosed. A first isotope is precipitated and is collected from the solution. A daughter isotope is generated and collected from the first isotope. The invention includes a method of producing an actinium-225/bismuth-213 product from a material containing thorium-229 and thorium-232. A solution is formed containing nitric acid and the material containing thorium-229 and thorium-232, and iodate is added to form a thorium iodate precipitate. A supernatant is separated from the thorium iodate precipitate and a second volume of nitric acid is added to the thorium iodate precipitate. The thorium iodate precipitate is stored and a decay product comprising actinium-225 and bismuth-213 is generated in the second volume of nitric acid, which is then separated from the thorium iodate precipitate, filtered, and treated using at least one chromatographic procedure. A system for producing an actinium-225/bismuth-213 product is also disclosed.

  4. The use of carbon stable isotope ratios in drugs characterization

    SciTech Connect (OSTI)

    Magdas, D. A., E-mail: gabriela.cristea@itim-cj.ro; Cristea, G., E-mail: gabriela.cristea@itim-cj.ro; Bot, A., E-mail: gabriela.cristea@itim-cj.ro; Mirel, V., E-mail: gabriela.cristea@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Str., 400293 Cluj-Napoca (Romania)

    2013-11-13

    Isotopic Ratio Mass Spectrometry (IRMS) is an effective toll to be used for drug product authentication. The isotopic composition could be used to assist in the differentiation between batches of drugs and assist in the identification of counterfeit materials on the market. Only two factors affect the isotopic ratios in pharmaceutical components: the isotopic composition of the raw materials and the synthetic processes performed upon them. Counterfeiting of pharmaceutical drugs threatens consumer confidence in drug products companies' economical well-being. In this preliminary study, the analyzed samples consist in two types of commercially available analgesics, which were purchases from Romanian pharmacies. Differences in ?{sup 13}C between batches from ?29.7 to ?31.6% were observed, demonstrating that this method can be used to differentiate among individual drug batches and subsequently identify counterfeits on the market. On the other hand, carbon isotopic ratios differences among producers were recorded, the variations being between ?31.3 to ?34.9% for the same type of analgesic, but from different manufactures.

  5. On the origin of the lightest Molybdenum isotopes

    E-Print Network [OSTI]

    Jacob Lund Fisker; Robert D. Hoffman; Jason Pruet

    2009-01-15

    We discuss implications of recent precision measurements for the Rh93 proton separation energy for the production of the lightest molybdenum isotopes in proton-rich type II supernova ejecta. It has recently been shown that a novel neutrino-induced process makes these ejecta a promising site for the production of the light molybdenum isotopes and other "p-nuclei" with atomic mass near 100. The origin of these isotopes has long been uncertain. A distinguishing feature of nucleosynthesis in neutrino-irradiated outflows is that the relative production of Mo92 and Mo94 is set by a competition governed by the proton separation energy of Rh93. We use detailed nuclear network calculations and the recent experimental results for this proton separation energy to place constraints on the outflow characteristics that produce the lightest molybdenum isotopes in their solar proportions. It is found that for the conditions calculated in recent two-dimensional supernova simulations, and also for a large range of outflow characteristics around these conditions, the solar ratio of Mo92 to Mo94 cannot be achieved. This suggests that either proton-rich winds from type II supernova do not exclusively produce both isotopes, or that these winds are qualitatively different than calculated in today's supernova models.

  6. Isotopically Enriched Films and Nanostructures by Ultrafast Pulsed Laser Deposition

    SciTech Connect (OSTI)

    Peter Pronko

    2004-12-13

    This project involved a systematic study to apply newly discovered isotopic enrichment effects in laser ablation plumes to the fabrication of isotopically engineered thin films, superlattices, and nanostructures. The approach to this program involved using ultrafast lasers as a method for generating ablated plasmas that have preferentially structured isotopic content in the body of the ablation plasma plumes. In examining these results we have attempted to interpret the observations in terms of a plasma centrifuge process that is driven by the internal electro-magnetic fields of the plasma itself. The research plan involved studying the following phenomena in regard to the ablation plume and the isotopic mass distribution within it: (1) Test basic equations of steady state centrifugal motion in the ablation plasma. (2) Investigate angular distribution of ions in the ablation plasmas. (3) Examine interactions of plasma ions with self-generated magnetic fields. (3) Investigate ion to neutral ratios in the ablation plasmas. (5) Test concepts of plasma pumping. (6) Fabricate isotopically enriched nanostructures.

  7. Possible differences in biological availability of isotopes of plutonium: Report of a workshop

    SciTech Connect (OSTI)

    Kercher, J.R.; Gallegos, G.M.

    1993-09-01

    This paper presents the results of a workshop conducted on the apparent different bioavailability of isotopes {sup 238}Pu and {sup 239}Pu. There is a substantial body of evidence that {sup 238}Pu as commonly found in the environment is more biologically available than {sup 239}Pu. Studies of the Trinity Site, Nevada Test Site from nonnuclear and nuclear events, Rocky Flats, Enewetak and Bikini, and the arctic tundra support this conclusion and indicate that the bioavailability of {sup 238}Pu is more than an order of magnitude greater than that of {sup 239}Pu. Plant and soil studies from controlled environments and from Savannah River indicate no isotopic difference in availability of Pu to plants; whereas studies at the Trinity Site do suggest a difference. While it is possible that these observations can be explained by problems in the experimental procedure and analytical techniques, this possibility is remote given the ubiquitous nature of the observations. Studies of solubility of Pu in the stomach contents of cattle grazing at the Nevada Test Site and from fish from Bikini Atoll both found that {sup 238}Pu was more soluble than {sup 239}Pu. Studies of the Los Alamos effluent stream indicate that as particle size decreases, the content of {sup 238}Pu relative to {sup 239}Pu increases.

  8. NATURAL GAS MARKET ASSESSMENT

    E-Print Network [OSTI]

    CALIFORNIA ENERGY COMMISSION NATURAL GAS MARKET ASSESSMENT PRELIMINARY RESULTS In Support.................................................................................... 6 Chapter 2: Natural Gas Demand.................................................................................................. 10 Chapter 3: Natural Gas Supply

  9. Worldwide, accelerating glacier loss provides independent and startling evidence that global warming is occurring1 It is now clear that the Earth is warming rapidly due to man-made emissions of carbon dioxide and other heat-trap-

    E-Print Network [OSTI]

    Combes, Stacey A.

    such as coal, oil and natural gas are burned for trans- portation, heating, or the production of electricity! Climate Change And Global Glacier Decline Global Warming is melting glaciers in every region of the world that global warming is occurring1 . It is now clear that the Earth is warming rapidly due to man

  10. Kidney cancer is one of the most common cancers occurring in 1-2% of individuals in their

    E-Print Network [OSTI]

    O'Hern, Corey S.

    Kidney cancer is one of the most common cancers occurring in 1-2% of individuals in their lifetime. The current incidence in the United States is approximately 60,000-cases/ year. While many cancers were believed to occur sporadically, it's now understood approximately 5-8% of kidney cancers have a genetic

  11. It has been demonstrated that pictures whose names occur more frequently (e.g., dog) are named faster than

    E-Print Network [OSTI]

    Caramazza, Alfonso

    It has been demonstrated that pictures whose names occur more frequently (e.g., dog) are named faster than pictures whose names occur less frequently (e.g., deer; Oldfield & Wingfield, 1965 with variables like structural similarity in picture naming experiments (Humphreys, Riddoch, & Quinlan, 1988

  12. 2006 Nature Publishing Group Arctic hydrology during global warming at the

    E-Print Network [OSTI]

    © 2006 Nature Publishing Group Arctic hydrology during global warming at the Palaeocene The Palaeocene/Eocene thermal maximum represents a period of rapid, extreme global warming ,55 million years ago global warming6 . The terrestrial-plant carbon isotope excursion (about 24.5 to 26 per mil

  13. Solubility trapping in formation water as dominant CO2 sink in natural gas fields

    E-Print Network [OSTI]

    Haszeldine, Stuart

    LETTERS Solubility trapping in formation water as dominant CO2 sink in natural gas fields Stuart M, dissolu- tion in formation water at a pH of 5­5.8 is the sole major sink for CO2. In two fields dissolved in water. Noble gas and CO2 carbon isotopes are powerful tracers of crustal fluid processes

  14. Simple, rapid method for the preparation of isotopically labeled formaldehyde

    DOE Patents [OSTI]

    Hooker, Jacob Matthew (Port Jefferson, NY); Schonberger, Matthias (Mains, DE); Schieferstein, Hanno (Aabergen, DE); Fowler, Joanna S. (Bellport, NY)

    2011-10-04

    Isotopically labeled formaldehyde (*C.sup..sctn.H.sub.2O) is prepared from labeled methyl iodide (*C.sup..sctn.H.sub.3I) by reaction with an oxygen nucleophile having a pendant leaving group. The mild and efficient reaction conditions result in good yields of *C.sup..sctn.H.sub.2O with little or no *C isotopic dilution. The simple, efficient production of .sup.11CH.sub.2O is described. The use of the .sup.11CH.sub.2O for the formation of positron emission tomography tracer compounds is described. The reaction can be incorporated into automated equipment available to radiochemistry laboratories. The isotopically labeled formaldehyde can be used in a variety of reactions to provide radiotracer compounds for imaging studies as well as for scintillation counting and autoradiography.

  15. METHOD TO TEST ISOTOPIC SEPARATION EFFICIENCY OF PALLADIUM PACKED COLUMNS

    SciTech Connect (OSTI)

    Heung, L; Gregory Staack, G; James Klein, J; William Jacobs, W

    2007-06-27

    The isotopic effect of palladium has been applied in different ways to separate hydrogen isotopes for many years. At Savannah River Site palladium deposited on kieselguhr (Pd/k) is used in a thermal cycling absorption process (TCAP) to purify tritium for over ten years. The need to design columns for different throughputs and the desire to advance the performance of TCAP created the need to evaluate different column designs and packing materials for their separation efficiency. In this work, columns with variations in length, diameter and metal foam use, were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages using the test results. The effects of column diameter, metal foam and gas flow rate were identified.

  16. Tests of isotopic separation efficiency of palladium packed columns

    SciTech Connect (OSTI)

    Heung, L. K.; Staack, G. C.; Klein, J. E.; Jacobs, W. D.

    2008-07-15

    The isotopic effect of palladium has been applied in different ways to separate hydrogen isotopes for many years. At Savannah River Site palladium deposited on kieselguhr (Pd/k) is used in a thermal cycling absorption process (TCAP) to purify tritium for over ten years. The need to design columns for different throughputs and the desire to advance the performance of TCAP created the need to evaluate different column designs and packing materials for their separation efficiency. In this work, columns with variations in length, diameter and metal foam presence were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages based on the test results. The effects of column diameter, metal foam presence and gas flow rate were identified. (authors)

  17. Natural Abundance Carbon Isotope Composition of Isoprene Reflects Incomplete Coupling between Isoprene

    E-Print Network [OSTI]

    discrimination step was the deoxyxylulose-5-phosphate synthase reaction. 2-Methyl-1,3-butadiene (isoprene

  18. Shell structure of potassium isotopes deduced from their magnetic moments

    E-Print Network [OSTI]

    J. Papuga; M. L. Bissell; K. Kreim; C. Barbieri; K. Blaum; M. De Rydt; T. Duguet; R. F. Garcia Ruiz; H. Heylen; M. Kowalska; R. Neugart; G. Neyens; W. Nortershauser; M. M. Rajabali; R. Sanchez; N. Smirnova; V. Soma; D. T. Yordanov

    2014-10-03

    \\item[Background] Ground-state spins and magnetic moments are sensitive to the nuclear wave function, thus they are powerful probes to study the nuclear structure of isotopes far from stability. \\item[Purpose] Extend our knowledge about the evolution of the $1/2^+$ and $3/2^+$ states for K isotopes beyond the $N = 28$ shell gap. \\item[Method] High-resolution collinear laser spectroscopy on bunched atomic beams. \\item[Results] From measured hyperfine structure spectra of K isotopes, nuclear spins and magnetic moments of the ground states were obtained for isotopes from $N = 19$ up to $N = 32$. In order to draw conclusions about the composition of the wave functions and the occupation of the levels, the experimental data were compared to shell-model calculations using SDPF-NR and SDPF-U effective interactions. In addition, a detailed discussion about the evolution of the gap between proton $1d_{3/2}$ and $2s_{1/2}$ in the shell model and {\\it{ab initio}} framework is also presented. \\item[Conclusions] The dominant component of the wave function for the odd-$A$ isotopes up to $^{45}$K is a $\\pi 1d_{3/2}^{-1}$ hole. For $^{47,49}$K, the main component originates from a $\\pi 2s_{1/2}^{-1}$ hole configuration and it inverts back to the $\\pi 1d_{3/2}^{-1}$ in $^{51}$K. For all even-$A$ isotopes, the dominant configuration arises from a $\\pi 1d_{3/2}^{-1}$ hole coupled to a neutron in the $\

  19. Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability

    E-Print Network [OSTI]

    Isselhardt, Brett Hallen

    2011-01-01

    4.5 Uranium Isotope Ratio Measurements . . . . . .4.32 Uranium sputtered from three U-rich materials of varying uranium isotopic

  20. DESIGN OF A SUBCRITICAL AQUEOUS TARGET SYSTEM FOR MEDICAL ISOTOPE PRODUCTION 

    E-Print Network [OSTI]

    Vega, Richard Manuel

    2013-12-10

    The United States consumes almost half of all medical isotopes produced worldwide, and relies on foreign sources for nearly its entire supply. These isotopes are produced in nuclear reactors which are very costly to construct. A domestic supply may...

  1. Lead Isotopic Variations of the Pacific and Implications for Paleogene Water Mass Composition 

    E-Print Network [OSTI]

    Subt, Cristina

    2013-11-13

    meridional temperature gradients. Nd isotopes indicate high-latitude convection in the Pacific Ocean during this interval, with deep waters mixing in the tropical Pacific. Here we investigate the evolution of the Pb isotopic composition of water masses...

  2. Uranium-series isotope and thermal constraints on the rate and depth of silicic magma genesis

    E-Print Network [OSTI]

    Sandiford, Mike

    Uranium-series isotope and thermal constraints on the rate and depth of silicic magma genesis A Sciences, University of Durham, South Road, Durham DH1 3LE, UK Abstract: Uranium-series isotopes provide

  3. Intramolecular Isotope Effects for the Study of Reactions with MassTransfer Limitations 

    E-Print Network [OSTI]

    Wagner, Joshua G.

    2010-01-16

    The research presented provides a method to use the comparison of intermolecular isotope effects vs. the intramolecular isotope effects for the study of reactions in which study of the rate limiting step is ambiguous due to interfering mass transfer...

  4. CARBON ISOTOPE STRATIGRAPHY AND DIAGENESIS OF PENNSYLVANIAN (DESMOINESIAN-MISSOURIAN) CARBONATES IN EAST-CENTRAL IDAHO 

    E-Print Network [OSTI]

    Wood, Stephanie

    2011-05-10

    Carbon isotope stratigraphy of carbonate sediments is instrumental in examining major perturbations in the global carbon cycle and in correlating strata. However, the primary isotopic signal recorded in these sediments can vary with depositional...

  5. Tuesday, March 24, 2009 POSTER SESSION I: EARLY NEBULAR PROCESSES: MODELS AND ISOTOPES

    E-Print Network [OSTI]

    Rathbun, Julie A.

    to H2O in adsorption/desorption kinetics. Nielsen S. G. Prytulak J. Halliday A. N. Vanadium Isotope presents the first method that produces high precision vanadium isotope data for terrestrial rocks

  6. Fragment Isotope Distributions and the Isospin Dependent Equation of State

    E-Print Network [OSTI]

    W. P. Tan; B-A. Li; R. Donangelo; C. K. Gelbke; M-J. van Goetherm; X. D. Liu; W. G. Lynch; S. Souza; M. B. Tsang; G. Verde; A. Wagner; N. S. Xu

    2001-04-21

    Calculations predict a connection between the isotopic composition of particles emitted during an energetic nucleus-nucleus collision and the density dependence of the asymmetry term of the nuclear equation of state (EOS). This connection is investigated for central 112Sn+112Sn and 124Sn+124Sn collisions at E/A=50 MeV in the limit of an equilibrated freezeout condition. Comparisons between measured isotopic yields ratios and theoretical predictions in the equilibrium limit are used to assess the sensitivity to the density dependence of the asymmetry term of the EOS. This analysis suggests that such comparisons may provide an opportunity to constrain the asymmetry term of the EOS.

  7. Equations of state and phase diagrams of hydrogen isotopes

    SciTech Connect (OSTI)

    Urlin, V. D.

    2013-11-15

    A new form of the semiempirical equation of state proposed for the liquid phase of hydrogen isotopes is based on the assumption that its structure is formed by cells some of which contain hydrogen molecules and others contain hydrogen atoms. The values of parameters in the equations of state of the solid (molecular and atomic) phases as well as of the liquid phase of hydrogen isotopes (protium and deuterium) are determined. Phase diagrams, shock adiabats, isentropes, isotherms, and the electrical conductivity of compressed hydrogen are calculated. Comparison of the results of calculations with available experimental data in a wide pressure range demonstrates satisfactory coincidence.

  8. Shape transition in the even-even Cerium isotopes

    E-Print Network [OSTI]

    B. Mohammed-Azizi; A. Helmaoui; D. E. Medjadi

    2015-04-29

    The deformation energy of the even-even nuclei of the Cerium isotopic chain is investigated by means of the Macroscopic-Microscopic method with a semi-classical shell correction. We consider axially symmetric shapes. Binding energy and two neutron separation energy are also evaluated. For the sake of clarity several important details of the calculations are also given. It turns out that all these nuclei have prolate equilibrium shape. The regions of maximum deformation are obtained around N=64 and N=102. There is no critical-point of quantum phase transition in this isotopic chain.

  9. Atomic vapor laser isotope separation using resonance ionization

    SciTech Connect (OSTI)

    Comaskey, B.; Crane, J.; Erbert, G.; Haynam, C.; Johnson, M.; Morris, J.; Paisner, J.; Solarz, R.; Worden, E.

    1986-09-01

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power-reactor fuel has been under development for over 10 years. In June 1985, the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for enriched uranium. Resonance photoionization is the heart of the AVLIS process. We discuss those fundamental atomic parameters that are necessary for describing isotope-selective resonant multistep photoionization along with the measurement techniques that we use. We illustrate the methodology adopted with examples of other elements that are under study in our program.

  10. Natural Gas Basics

    SciTech Connect (OSTI)

    NREL Clean Cities

    2010-04-01

    Fact sheet answers questions about natural gas production and use in transportation. Natural gas vehicles are also described.

  11. Tunneling effects in the kinetics of helium and hydrogen isotopes desorption from single-walled carbon nanotube bundles

    SciTech Connect (OSTI)

    Danilchenko, B. A. Yaskovets, I. I.; Uvarova, I. Y.; Dolbin, A. V.; Esel'son, V. B.; Basnukaeva, R. M.; Vinnikov, N. A.

    2014-04-28

    The kinetics of desorption both helium isotopes and molecules of hydrogen and deuterium from open-ended or ?-irradiated single-walled carbon nanotube bundles was investigated in temperature range of 10–300?K. The gases desorption rates obey the Arrhenius law at high temperatures, deviate from it with temperature reduction and become constant at low temperatures. These results indicate the quantum nature of gas outflow from carbon nanotube bundles. We had deduced the crossover temperature below which the quantum corrections to the effective activation energy of desorption become significant. This temperature follows linear dependence against the inverse mass of gas molecule and is consistent with theoretical prediction.

  12. Isotopic generator for bismuth-212 and lead-212 based on radium

    DOE Patents [OSTI]

    Hines, J.J.; Atcher, R.W.; Friedman, A.M.

    1985-01-30

    Disclosed are method and apparatus for providing radionuclides of bismuth-212 and lead-212. Thorium-228 and carrier solution starting material is input to a radiologically contained portion of an isotopic generator system, and radium-224 is separated from thorium-228 which is retained by a strongly basic anion exchange column. The separated radium-224 is transferred to an accessible, strongly acidic cationic exchange column. The cationic column retains the radium-224, and natural radioactive decay generates bismuth-212 and lead-212. The cationic exchange column can also be separated from the contained portion of the system and utilized without the extraordinary safety measures necessary in the contained portion. Furthermore, the cationic exchange column provides over a relatively long time period the short lived lead-212 and bismuth-212 radionuclides which are useful for a variety of medical therapies.

  13. Separation and concentration of hydrogen isotopes by a palladium alloy membrane

    SciTech Connect (OSTI)

    Suzuki, Yasuo ); Kimura, Shoji )

    1993-07-01

    A continuous membrane column process that uses a palladium alloy membrane for the separation of hydrogen isotopes is studied. Hydrogen, deuterium, and tritium permeation rates obtained in previous studies are used in numerical calculations in which the nature of the membrane column is investigated through variations in the operation variables, such as the pressures and their ratio, the reflux ratio, and the stripping column velocity. Finally, a cascade design in which membrane columns are used as unit cells is developed, following a design study of a nuclear fusion reactor fuel cycle system, and the concentrations and flow rates are calculated. The results show that hydrogen, deuterium, and tritium can be separated and concentrated as well by this method as by the liquid hydrogen distillation process. The inventory of the membrane column process is also calculated, and it is [approximately]2.3 times the fuel processed in a day.

  14. Method for enriching a middle isotope using vibration-vibration pumping

    DOE Patents [OSTI]

    Rich, Joseph W. (East Aurora, NY); Homicz, Gregory F. (Getzville, NY); Bergman, Richard C. (Corfu, NY)

    1989-01-01

    Method for producing isotopically enriched material by vibration-vibration excitation of gaseous molecules wherein a middle mass isotope of an isotopic mixture including lighter and heavier mass isotopes preferentially populates a higher vibrational mode and chemically reacts to provide a product in which it is enriched. The method can be used for vibration-vibration enrichment of .sup.17 O in a CO reactant mixture.

  15. Viscosities of natural gases at high pressures and high temperatures 

    E-Print Network [OSTI]

    Viswanathan, Anup

    2007-09-17

    Estimation of viscosities of naturally occurring petroleum gases provides the information needed to accurately work out reservoir-engineering problems. Existing models for viscosity prediction are limited by data, especially at high pressures...

  16. Natural ventilation possibilities for buildings in the United States

    E-Print Network [OSTI]

    Dean, Brian N. (Brian Nathan), 1974-

    2001-01-01

    In the United States, many of the commercial buildings built in the last few decades are completely mechanically air conditioned, without the capability to use natural ventilation. This habit has occurred in building designs ...

  17. Dual isotope notch observer for isotope identification, assay and imaging with mono-energetic gamma-ray sources

    DOE Patents [OSTI]

    Barty, Christopher P.J.

    2013-02-05

    A dual isotope notch observer for isotope identification, assay and imaging with mono-energetic gamma-ray sources includes a detector arrangement consists of three detectors downstream from the object under observation. The latter detector, which operates as a beam monitor, is an integrating detector that monitors the total beam power arriving at its surface. The first detector and the middle detector each include an integrating detector surrounding a foil. The foils of these two detectors are made of the same atomic material, but each foil is a different isotope, e.g., the first foil may comprise U235 and second foil may comprise U238. The integrating detectors surrounding these pieces of foil measure the total power scattered from the foil and can be similar in composition to the final beam monitor. Non-resonant photons will, after calibration, scatter equally from both foils.

  18. Challenges in Determining the Isotopic Mixture for the Fukushima Daiichi Nuclear Power Plant

    SciTech Connect (OSTI)

    Shanks, Arthur [Sandia National Laboratories; Fournier, Sean [Sandia National Laboratories; Shanks, Sonoya [Sandia National Laboratories

    2012-05-01

    As part of the United States response to the Fukushima Daiichi Nuclear Power Plant emergency, the National Nuclear Security Administration (NNSA) Consequence Management (CM) Teams were activated with elements deploying to Japan. The NNSA CM teams faced the urgent need for information regarding the potential radiological doses that citizens of might experience. This paper discusses the challenges and lessons learned associated with the analysis of field collected samples and gamma spectra in an attempt to determine the isotopic mixture present on the ground around the Plant. There were several interesting and surprising lessons to be learned from the sample analysis portion of the response. The paper discusses several elements of the response that were unique to the event occurring in Japan, as well as several elements that would have occurred in a U.S. nuclear reactor event. Sections of this paper address details of the specific analytical challenges faced during the efforts to analyze samples and try to understand the overall release source term.

  19. LEAD ISOTOPIC ANALYSIS FOR THE IDENTIFICATION OF LATE BRONZE AGE POTTERY FROM HALA SULTAN

    E-Print Network [OSTI]

    Claeys, Philippe

    LEAD ISOTOPIC ANALYSIS FOR THE IDENTIFICATION OF LATE BRONZE AGE POTTERY FROM HALA SULTAN TEKKE, 9000 Ghent 5 Department of Geology, Université de Liège, Allée du 6­Août B18, 4000 Liège Lead isotopic the effectiveness of using lead isotopic analysis in provenance studies, along with other analytical techniques

  20. COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE

    E-Print Network [OSTI]

    Claeys, Philippe

    COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE Brussels, Belgium 6 Director of research at Hala Sultan Tekke, Area 8, Cyprus Lead isotopes, thin sections and com- pared to lead isotope results on the same samples. This study shows that a specific

  1. Dynamic isotope effect on the product energy partitioning in CH2OH ~CHO H2

    E-Print Network [OSTI]

    Kim, Myung Soo

    Dynamic isotope effect on the product energy partitioning in CH2OH ~CHO H2 Young Min Rheea March 1998; accepted 1 July 1998 The deuterium isotope effect on the product energy partitioning. Close inspection of the potential energy surface revealed that the isotope effect on KER and the product

  2. Hydrogen isotopic variability in leaf waxes among terrestrial and aquatic plants around Blood Pond, Massachusetts (USA)

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Hydrogen isotopic variability in leaf waxes among terrestrial and aquatic plants around Blood Pond interpretation of the hydrogen isotope ratios of plant leaf waxes extracted from sediments requires a thor- ough at a single site to determine how leaf wax hydro- gen isotope (D/H) ratios differ in different plant types

  3. Hydrogen isotope fractionation in freshwater algae: I. Variations among lipids and species

    E-Print Network [OSTI]

    Sachs, Julian P.

    Hydrogen isotope fractionation in freshwater algae: I. Variations among lipids and species Zhaohui in media containing different concentrations of deuterium. The hydrogen isotopic ratios of lipids that lipid dD values can be used to determine water dD values, hydrogen isotope fractionation was found

  4. 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

  5. Using phylogenetic probes for quantification of stable isotope labeling and microbial community analysis

    DOE Patents [OSTI]

    Brodie, Eoin L; DeSantis, Todd Z; Karaoz, Ulas; Andersen, Gary L

    2014-12-09

    Herein is described methods for a high-sensitivity means to measure the incorporation of stable isotope labeled substrates into RNA following stable isotope probing experiments (SIP). RNA is hybridized to a set of probes such as phylogenetic microarrays and isotope incorporation is quantified such as by secondary ion mass spectrometer imaging (NanoSIMS).

  6. Nitrogen concentration and isotope dataset for environmental samples from 2012 and 2013, Barrow, Alaska

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jeff Heikoop; Heather Throckmorton

    2015-05-15

    Dataset includes nitrate concentrations for polygonal active layer samples, snowmelt; ammonium concentrations for active layer samples; nitrate isotopes for active layer samples, snowmelt, permafrost; ammonium isotopes for active layer samples; and nitrogen isotopes for soils and dissolved organic nitrogen extracted from soil pore waters.

  7. Nitrogen concentration and isotope dataset for environmental samples from 2012 and 2013, Barrow, Alaska

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jeff Heikoop; Heather Throckmorton

    Dataset includes nitrate concentrations for polygonal active layer samples, snowmelt; ammonium concentrations for active layer samples; nitrate isotopes for active layer samples, snowmelt, permafrost; ammonium isotopes for active layer samples; and nitrogen isotopes for soils and dissolved organic nitrogen extracted from soil pore waters.

  8. An intramolecular theory of the mass-independent isotope effect for ozone. I.

    E-Print Network [OSTI]

    Hathorn, Bryan C.

    An intramolecular theory of the mass-independent isotope effect for ozone. I. B. C. Hathorn and R-independent isotope effect for ozone formation and dissociation is described. The experiments include the enrichment and asymmetric ozone isotopomers, the enrichment of ozone formed from heavily enriched oxygen isotopes

  9. Carbon Isotope Constraints on the Deglacial CO2 Rise from Ice Cores

    E-Print Network [OSTI]

    Stocker, Thomas

    controls the isotopic fractionation during air/sea gas exchange. The continuous rain of isotopically light carbon storage, which result in a net change in the carbon isotopic composition of the ocean--EPICA (Europe- an Project for Ice Coring in Antarctica) Dome C and Talos Dome--performed with three independent

  10. Lithium isotopic systematics of granites and pegmatites from the Black Hills, South Dakota

    E-Print Network [OSTI]

    Rudnick, Roberta L.

    Lithium isotopic systematics of granites and pegmatites from the Black Hills, South Dakota Fang compositions may reflect Li isotopic fractionation resulting from extensive crystal-melt fractionation. Lithium fractionation in the near­surface environment of > 60 (Tomascak, 2004). Lithium isotopic fractionation has been

  11. Extreme lithium isotopic fractionation during continental weathering revealed in saprolites from South Carolina

    E-Print Network [OSTI]

    Rudnick, Roberta L.

    Extreme lithium isotopic fractionation during continental weathering revealed in saprolites from in revised form 6 July 2004 Abstract The lithium concentration and isotopic composition of two saprolites the behavior of lithium isotopes during continental weathering. Both saprolites show a general trend

  12. Stable-carbon isotope composition of Poaceae pollen: an assessment for

    E-Print Network [OSTI]

    Hu, Feng Sheng

    2006 Abstract: Plants using the C3 and C4 photosynthetic pathways differ in carbon-isotope composition-isotope compositions primarily because they use different enzymes for initial carbon fixation: ribulose-1Stable-carbon isotope composition of Poaceae pollen: an assessment for reconstructing C3 and C4

  13. Physical controls on the isotopic composition of soil-respired CO2

    E-Print Network [OSTI]

    Physical controls on the isotopic composition of soil-respired CO2 Nick Nickerson1 and Dave Risk1] Measurement of the isotopic composition of soil and soil-respired CO2 (d13 CO2) has become an invaluable tool in understanding the effects of diffusive transport on soil CO2 isotopic composition, it is crucial

  14. Discovery of Isotopes of the Transuranium Elements with 93 <= Z <= 98

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-04-26

    One hundred and five isotopes of the transuranium elements neptunium, plutonium, americium, curium, berkelium and californium have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  15. 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

  16. The Valles natural analogue project

    SciTech Connect (OSTI)

    Stockman, H.; Krumhansl, J.; Ho, C. [Sandia National Labs., Albuquerque, NM (United States); McConnell, V. [Alaska Univ., Fairbanks, AK (United States). Geophysical Inst.

    1994-12-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a highlevel waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, X-ray diffraction; and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and {sup 39}Ar/{sup 4O} isotopic composition. Overall,the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 meters of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks.

  17. Science with Beams of Radioactive Isotopes

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopment Top LDRDUniversitySchedulesScienceProjectionsScience

  18. Isotopic evidence for Mesoarchaean anoxia and changing atmospheric sulphur chemistry

    E-Print Network [OSTI]

    Kaufman, Alan Jay

    LETTERS Isotopic evidence for Mesoarchaean anoxia and changing atmospheric sulphur chemistry James changes in pre-2.45-Gyr-ago atmospheric pathways for non-mass-dependent chemistry and in the ultraviolet J. Kaufman1 The evolution of the Earth's atmosphere is marked by a transition from an early

  19. Carbon and Hydrogen Isotopic Effects in Microbial Methane

    E-Print Network [OSTI]

    Saleska, Scott

    6 Carbon and Hydrogen Isotopic Effects in Microbial Methane from Terrestrial Environments Jeffrey Chanton, Lia Chaser, Paul Glasser,Don Siegel Methane is the ultimate end-product of anaerobic respiration. Methane production via CO2 reduction does not consume CO2. Also, acetate can be written as 2CH20, so Eq. 6

  20. CRAD, Management- Oak Ridge National Laboratory High Flux Isotope Reactor

    Broader source: Energy.gov [DOE]

    A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2007 assessment of the Management in preparation for restart of the Oak Ridge National Laboratory High Flux Isotope Reactor.

  1. Apparatus and method for monitoring of gas having stable isotopes

    DOE Patents [OSTI]

    Clegg, Samuel M; Fessenden-Rahn, Julianna E

    2013-03-05

    Gas having stable isotopes is monitored continuously by using a system that sends a modulated laser beam to the gas and collects and transmits the light not absorbed by the gas to a detector. Gas from geological storage, or from the atmosphere can be monitored continuously without collecting samples and transporting them to a lab.

  2. Use of Strontium Isotopes to Identify Buried Water Main Leakage

    E-Print Network [OSTI]

    Jiao, Jiu Jimmy

    Use of Strontium Isotopes to Identify Buried Water Main Leakage Into Groundwater in a Highly water mains. The identification of leakage locations was done by conventional water quality parameters to identify leakage locations especially where the leakage is from drinking water mains because the chemical

  3. Examining the stability of thermally fissile Th and U isotopes

    E-Print Network [OSTI]

    Kumar, Bharat; Singh, S K; Patra, S K

    2015-01-01

    The properties of recently predicted thermally fissile Th and U isotopes are studied within the framework of relativistic mean field (RMF) approach using axially deformed basis. We calculated the ground, first intrinsic excited state and matter density for highly neutron-rich thorium and uranium isotopes. The possible modes of decay like $\\alpha$-decay and $\\beta$-decay are analyzed. We found that the neutron-rich isotopes are stable against $\\alpha$-decay, however they are very much unstable against $\\beta$-decay. The life time of these nuclei predicted to be tens of second against $\\beta$-decay. If these nuclei utilize before their decay time, a lots of energy can be produced within the help of multi-fragmentation fission. Also, these nuclei have a great implication in astrophysical point of view. The total nucleonic densities distribution are calculated, from which the clusters inside the parent nuclei are determined. %Most of the thorium isotopes are $\\alpha$ emitters, where as some %of them have short ha...

  4. Rare Isotope Beams for the 21st Century

    ScienceCinema (OSTI)

    James Symons

    2010-01-08

    In a scientific keynote address on Friday, June 12 at Michigan State University (MSU) in East Lansing, James Symons, Director of Berkeley Labs Nuclear Science Division (NSD), discussed the exciting research prospects of the new Facility for Rare Isotope Beams (FRIB) to be built at MSUs National Superconducting Cyclotron Laboratory.

  5. CRAD, Engineering- Oak Ridge National Laboratory High Flux Isotope Reactor

    Broader source: Energy.gov [DOE]

    A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2007 assessment of the Engineering Program in preparation for restart of the Oak Ridge National Laboratory High Flux Isotope Reactor.

  6. CRAD, Training- Oak Ridge National Laboratory High Flux Isotope Reactor

    Broader source: Energy.gov [DOE]

    A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2007 assessment of the Training Program in preparation for restart of the Oak Ridge National Laboratory High Flux Isotope Reactor.

  7. (Carbon isotope fractionation in plants): Annual technical progress report

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1988-01-01

    Plants fractionate carbon isotopes during photosynthesis in ways which reflect photosynthetic pathway and environment. The fractionation is product of contributions from diffusion, carboxylation and other factors which can be understood using models which have been developed in our work. The object of our work is to use this fractionation to learn about the factors which control the efficiency of photosynthesis. Unlike previous studies, we do not rely principally on combustion methods, but instead develop more specific methods with substantially higher resolving power. We have recently developed a new short-term method for studying carbon isotope fractionation which promises to provide a level of detail about temperature, species, and light intensity effects on photosynthesis which has not been available until now. We are studying the isotopic compositions of metabolites (particularly aspartic acid) in C/sub 3/ plants in order to determine the role of phosphoenolpyruvate carboxylase in C/sub 3/ photosynthesis. We are studying the relative roles of diffusion and carboxylation in nocturnal CO/sub 2/ fixation in CAM plants. We are studying the use of isotopic content as an index of water-use efficiency in C/sub 3/ plants. We are developing new methods for studying carbon metabolism in plants. 3 refs

  8. Method of enhancing selective isotope desorption from metals

    DOE Patents [OSTI]

    Knize, R.J.; Cecchi, J.L.

    1983-07-26

    This invention relates generally to the field of gas desorption from metals; and, more particularly, to a method of enhancing the selective desorption of a particular isotope of a gas from metals. Enhanced selective desorption is especially useful in the operation of fusion devices.

  9. 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

  10. Hydrogen Isotopic (D/H) Composition of Organic Matter

    E-Print Network [OSTI]

    Sessions, Alex L.

    Hydrogen Isotopic (D/H) Composition of Organic Matter During Diagenesis and Thermal Maturation difficult to interpret because the effects of hydrogen exchange and kinetic fractionations are confounded- crease in the D/H ratio of most organic hydrogen at the bulk and molecular levels, and suggest

  11. PLUTONIUM ISOTOPES I N THE NORTH ATLANTIC KEN 0. BUESSELER

    E-Print Network [OSTI]

    Buesseler, Ken

    PLUTONIUM ISOTOPES I N THE NORTH ATLANTIC by KEN 0. BUESSELER B.A., University of California The a r t i f i c i a l radionuclide Plutonium (Pu) has been introduced i n t o the environment p r i m

  12. Quantum origin of an anomalous isotope effect in ozone formation

    E-Print Network [OSTI]

    Reid, Scott A.

    Quantum origin of an anomalous isotope effect in ozone formation D. Babikov *, B.K. Kendrick, R mechanical calculations of the ðJ ¼ 0Þ energies and lifetimes of the metastable states of ozone on a new effect in the reaction that forms ozone because of their role in the energy transfer mechanism, in which

  13. Constraining magnesium cycling in marine sediments using magnesium isotopes

    E-Print Network [OSTI]

    Paytan, Adina

    . Extensive sampling of sedimentary pore-fluids by the Deep Sea Drilling Project (DSDP) and Ocean Drilling Abstract Magnesium concentrations in deep-sea sediment pore-fluids typically decrease down core due to net and differentiate these processes, we have measured magnesium isotopes in pore-fluids and sediment samples from

  14. CRAD, Maintenance- Oak Ridge National Laboratory High Flux Isotope Reactor

    Broader source: Energy.gov [DOE]

    A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2007 assessment of the Maintenance Program in preparation for restart of the Oak Ridge National Laboratory High Flux Isotope Reactor.

  15. Ab Initio Nuclear Structure and Reaction Calculations for Rare Isotopes

    SciTech Connect (OSTI)

    Draayer, Jerry P.

    2014-09-28

    We have developed a novel ab initio symmetry-adapted no-core shell model (SA-NCSM), which has opened the intermediate-mass region for ab initio investigations, thereby providing an opportunity for first-principle symmetry-guided applications to nuclear structure and reactions for nuclear isotopes from the lightest p-shell systems to intermediate-mass nuclei. This includes short-lived proton-rich nuclei on the path of X-ray burst nucleosynthesis and rare neutron-rich isotopes to be produced by the Facility for Rare Isotope Beams (FRIB). We have provided ab initio descriptions of high accuracy for low-lying (including collectivity-driven) states of isotopes of Li, He, Be, C, O, Ne, Mg, Al, and Si, and studied related strong- and weak-interaction driven reactions that are important, in astrophysics, for further understanding stellar evolution, X-ray bursts and triggering of s, p, and rp processes, and in applied physics, for electron and neutrino-nucleus scattering experiments as well as for fusion ignition at the National Ignition Facility (NIF).

  16. Comparative genomics in acid mine drainage biofilm communities reveals metabolic and structural differentiation of co-occurring archaea

    E-Print Network [OSTI]

    2013-01-01

    co-occurring archaea. BMC Genomics 2013 14:485. Submit yourgenomes. Yelton et al. BMC Genomics 2013, 14:485 http://work was supported by DOE Genomics: GTL project Grant No.

  17. Health Hazard Chart The following is a target organ categorization of effects that may occur, including examples of signs and

    E-Print Network [OSTI]

    Slatton, Clint

    Health Hazard Chart The following is a target organ categorization of effects that may occur which affect the eye or visual capacity Conjunctivitis, corneal damage Organic solvents, acids #12;

  18. Alternative applications of atomic vapor laser isotope separation technology

    SciTech Connect (OSTI)

    Not Available

    1991-01-01

    This report was commissioned by the Secretary of Energy. It summarizes the main features of atomic vapor laser isotope separation (AVLIS) technology and subsystems; evaluates applications, beyond those of uranium enrichment, suggested by Lawrence Livermore National Laboratory (LLNL) and a wide range of US industries and individuals; recommends further work on several applications; recommends the provision of facilities for evaluating potential new applications; and recommends the full involvement of end users from the very beginning in the development of any application. Specifically excluded from this report is an evaluation of the main AVLIS missions, uranium enrichment and purification of plutonium for weapons. In evaluating many of the alternative applications, it became clear that industry should play a greater and earlier role in the definition and development of technologies with the Department of Energy (DOE) if the nation is to derive significant commercial benefit. Applications of AVLIS to the separation of alternate (nonuranium) isotopes were considered. The use of {sup 157}Gd as burnable poison in the nuclear fuel cycle, the use {sup 12}C for isotopically pure diamond, and the use of plutonium isotopes for several nonweapons applications are examples of commercially useful products that might be produced at a cost less than the product value. Separations of other isotopes such as the elemental constituents of semiconductors were suggested; it is recommended that proposed applications be tested by using existing supplies to establish their value before more efficient enrichment processes are developed. Some applications are clear, but their production costs are too high, the window of opportunity in the market has passed, or societal constraints (e.g., on reprocessing of reactor fuel) discourage implementation.

  19. Laser-induced separation of hydrogen isotopes in the liquid phase

    DOE Patents [OSTI]

    Freund, Samuel M. (Los Alamos, NM); Maier, II, William B. (Los Alamos, NM); Beattie, Willard H. (Los Alamos, NM); Holland, Redus F. (Los Alamos, NM)

    1980-01-01

    Hydrogen isotope separation is achieved by either (a) dissolving a hydrogen-bearing feedstock compound in a liquid solvent, or (b) liquefying a hydrogen-bearing feedstock compound, the liquid phase thus resulting being kept at a temperature at which spectral features of the feedstock relating to a particular hydrogen isotope are resolved, i.e., a clear-cut isotope shift is delineated, irradiating the liquid phase with monochromatic radiation of a wavelength which at least preferentially excites those molecules of the feedstock containing a first hydrogen isotope, inducing photochemical reaction in the excited molecules, and separating the reaction product containing the first isotope from the liquid phase.

  20. Transient competitive complexation in biological kinetic isotope fractionation explains non-steady isotopic effects: Theory and application to denitrification in soils

    SciTech Connect (OSTI)

    Maggi, F.M.; Riley, W.J.

    2009-06-01

    The theoretical formulation of biological kinetic reactions in isotopic applications often assume first-order or Michaelis-Menten-Monod kinetics under the quasi-steady-state assumption to simplify the system kinetics. However, isotopic e ects have the same order of magnitude as the potential error introduced by these simpli cations. Both formulations lead to a constant fractionation factor which may yield incorrect estimations of the isotopic effect and a misleading interpretation of the isotopic signature of a reaction. We have analyzed the isotopic signature of denitri cation in biogeochemical soil systems by Menyailo and Hungate [2006], where high {sup 15}N{sub 2}O enrichment during N{sub 2}O production and inverse isotope fractionation during N{sub 2}O consumption could not be explained with first-order kinetics and the Rayleigh equation, or with the quasi-steady-state Michaelis-Menten-Monod kinetics. When the quasi-steady-state assumption was relaxed, transient Michaelis-Menten-Monod kinetics accurately reproduced the observations and aided in interpretation of experimental isotopic signatures. These results may imply a substantial revision in using the Rayleigh equation for interpretation of isotopic signatures and in modeling biological kinetic isotope fractionation with first-order kinetics or quasi-steady-state Michaelis-Menten-Monod kinetics.

  1. The production of ultra-high purity single isotopes or tailored isotope mixtures by ICP-MS

    SciTech Connect (OSTI)

    Liezers, Martin; Farmer, Orville T.; Dion, Michael P.; Thomas, Linda MP; Eiden, Gregory C.

    2015-01-01

    We report the development and testing of a simple collector arrangement for a commercial quadrupole ICP-MS that for the first time has been used to produce small quantities of highly enriched (>99.99%) single isotopes, with deposition rates >10 ng/hour. The collector assembly replaces the standard instrument detector allowing for implantation with simultaneous monitoring of the incident ion current. Even under zero bias implant conditions, low energy (<10 eV), ion collection efficiency was observed to be very high ~99%. 151Eu ion currents of 0.1-0.5 nA were collected on a simple, planar foil without resorting to any type of cup configuration. Recovery of the enriched isotope from such foils is much simpler than from a more complex cup configuration. High rejection of adjacent mass isotopes was demonstrated by selectively implanting 167Er without any discernible co-implantation of 166Er and 168Er. The important analytical possibilities of the new approach to isotope ratio measurement, tracer purification and radiation measurements are discussed.

  2. NATURE PUBLISHING GROUP SITE LICENSES

    E-Print Network [OSTI]

    Cai, Long

    Biotechnology Nature Cell Biology Nature Chemical Biology Nature Chemistry Nature Climate Change Nature of Information Technology Journal of Information Technology Teaching Cases Journal of International Business

  3. The Atomic Vapor Laser Isotope Separation Program. [Atomic Vapor Laser Isotope Separation (AVLIS) Program

    SciTech Connect (OSTI)

    Not Available

    1992-11-09

    This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management's position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted.

  4. Carbonyl sulfide hydrolysis in natural gas

    SciTech Connect (OSTI)

    Russo, F.; Caribotti, P.; Garofalo, N.

    1988-01-01

    Carbonyl sulfide may naturally occur in high H/sub 2/S - CO/sub 2/ content sour natural gases. Furthermore part of the H/sub 2/S present in natural gases may be converted into COS if molecular sieves are used as H/sub 2/S removal substances in natural gas desulphurization plants. Carbonyl sulfide might then hydrolize to H/sub 2/S in the gas storage fields and transmission lines. This paper illustrates experimental data relevant to the kinetics and thermodynamics of the reaction between carbonyl sulfide and water both at gas and gas/liquid phases. Results may suggest whether carbonyl sulfide should be included in natural gas quality specifications.

  5. 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

  6. Trace element abundances and Sr-Nd-Pb isotopic constraints on the petrogenesis of Juan Fernandez lavas

    E-Print Network [OSTI]

    Truong, Thi Bich

    2015-01-01

    isotope disequilibrium and geochronology of glassy submarineGeochemistry and geochronology of the Society Islands: New

  7. Natural Gas Applications

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Gas Applications. If you need assistance viewing this page, please call (202) 586-8800. Energy Information Administration Home Page Home > Natural Gas > Natural Gas Applications...

  8. Global Natural Gas Market Trends, 2. edition

    SciTech Connect (OSTI)

    2007-07-15

    The report provides an overview of major trends occurring in the natural gas industry and includes a concise look at the drivers behind recent rapid growth in gas usage and the challenges faced in meeting that growth. Topics covered include: an overview of Natural Gas including its history, the current market environment, and its future market potential; an analysis of the overarching trends that are driving a need for change in the Natural Gas industry; a description of new technologies being developed to increase production of Natural Gas; an evaluation of the potential of unconventional Natural Gas sources to supply the market; a review of new transportation methods to get Natural Gas from producing to consuming countries; a description of new storage technologies to support the increasing demand for peak gas; an analysis of the coming changes in global Natural Gas flows; an evaluation of new applications for Natural Gas and their impact on market sectors; and, an overview of Natural Gas trading concepts and recent changes in financial markets.

  9. ANALYSIS OF RICIN TOXIN PREPARATIONS FOR CARBOHYDRATE AND FATTY ACID ABUNDANCE AND ISOTOPE RATIO INFORMATION

    SciTech Connect (OSTI)

    Wunschel, David S.; Kreuzer-Martin, Helen W.; Antolick, Kathryn C.; Colburn, Heather A.; Moran, James J.; Melville, Angela M.

    2009-12-01

    This report describes method development and preliminary evaluation for analyzing castor samples for signatures of purifying ricin. Ricin purification from the source castor seeds is essentially a problem of protein purification using common biochemical methods. Indications of protein purification will likely manifest themselves as removal of the non-protein fractions of the seed. Two major, non-protein, types of biochemical constituents in the seed are the castor oil and various carbohydrates. The oil comprises roughly half the seed weight while the carbohydrate component comprises roughly half of the remaining “mash” left after oil and hull removal. Different castor oil and carbohydrate components can serve as indicators of specific toxin processing steps. Ricinoleic acid is a relatively unique fatty acid in nature and is the most abundant component of castor oil. The loss of ricinoleic acid indicates a step to remove oil from the seeds. The relative amounts of carbohydrates and carbohydrate-like compounds, including arabinose, xylose, myo-inositol fucose, rhamnose, glucosamine and mannose detected in the sample can also indicate specific processing steps. For instance, the differential loss of arabinose relative to mannose and N-acetyl glucosamine indicates enrichment for the protein fraction of the seed using protein precipitation. The methods developed in this project center on fatty acid and carbohydrate extraction from castor samples followed by derivatization to permit analysis by gas chromatography-mass spectrometry (GC-MS). Method descriptions herein include: the source and preparation of castor materials used for method evaluation, the equipment and description of procedure required for chemical derivatization, and the instrument parameters used in the analysis. Two types of derivatization methods describe analysis of carbohydrates and one procedure for analysis of fatty acids. Two types of GC-MS analysis is included in the method development, one employing a quadrupole MS system for compound identification and an isotope ratio MS for measuring the stable isotope ratios of deuterium and hydrogen (D/H) in fatty acids. Finally, the method for analyzing the compound abundance data is included. This study indicates that removal of ricinoleic acid is a conserved consequence of each processing step we tested. Furthermore, the stable isotope D/H ratio of ricinoleic acid distinguished between two of the three castor seed sources. Concentrations of arabinose, xylose, mannose, glucosamine and myo-inositol differentiated between crude or acetone extracted samples and samples produced by protein precipitation. Taken together these data illustrate the ability to distinguish between processes used to purify a ricin sample as well as potentially the source seeds.

  10. Stable Isotope Characterization of TICs/TIMs: Analytical Progress Report

    SciTech Connect (OSTI)

    Volpe, A M; Singleton, M J

    2009-06-05

    We measured twelve alkali cyanide samples that were also sent to ORNL and PNNL collaborators. While results indicate distinct {delta}{sup 13}C and {delta}{sup 15}N values that would be useful to signature studies, the alkali cyanides, especially NaCN, show chemical breakdown during storage that will influence forensic analysis. Carbon and nitrogen stable isotopic compositions of raw materials used to synthesis TETS were measured. Results indicate wide ranges in {delta}{sup 13}C and {delta}{sup 15}N values. Using these raw materials, LLNL scientists synthesized three batches of TETS following published procedures. Stable isotopic measurements of TETS synthesis products indicates nitrogen ({var_epsilon} {sup 15}N = -1.7 to -0.8) and carbon ({var_epsilon} {sup 13}C = -1.0 to -0.1) fractionation during production.

  11. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Arruda, Luísa; Borges, João; Carmo, Fernando; Gonçalves, Patrícia; Pereira, Rui; Pimenta, Mário

    2007-01-01

    The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station (ISS) in 2008, is a cosmic ray detector with several subsystems, one of which is a proximity focusing Ring Imaging Cherenkov (RICH) detector. This detector will be equipped with a dual radiator (aerogel+NaF), a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides, enabling precise measurements of particle electric charge and velocity. Combining velocity measurements with data on particle rigidity from the AMS Tracker it is possible to obtain a measurement for particle mass, allowing the separation of isotopes. A Monte Carlo simulation of the RICH detector, based on realistic properties measured at ion beam tests, was performed to evaluate isotope separation capabilities. Results for three elements -- H (Z=1), He (Z=2) and Be (Z=4) -- are presented.

  12. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Luísa Arruda; Fernando Barão; João Borges; Fernando Carmo; Patrícia Gonçalves; Rui Pereira; Mário Pimenta

    2007-10-03

    The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station (ISS) in 2008, is a cosmic ray detector with several subsystems, one of which is a proximity focusing Ring Imaging Cherenkov (RICH) detector. This detector will be equipped with a dual radiator (aerogel+NaF), a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides, enabling precise measurements of particle electric charge and velocity. Combining velocity measurements with data on particle rigidity from the AMS Tracker it is possible to obtain a measurement for particle mass, allowing the separation of isotopes. A Monte Carlo simulation of the RICH detector, based on realistic properties measured at ion beam tests, was performed to evaluate isotope separation capabilities. Results for three elements -- H (Z=1), He (Z=2) and Be (Z=4) -- are presented.

  13. Neutrino scattering off the stable even-even Mo isotopes

    SciTech Connect (OSTI)

    Balasi, K. G.; Kosmas, T. S.; Divari, P. C. [Theoretical Physics Section, University of Ioannina, GR 45110 Ioannina (Greece)

    2009-11-09

    Inelastic neutrino-nucleus reaction cross sections are studied focusing on the neutral current processes. Particularly, we investigate the angular and initial neutrino-energy dependence of the differential and integrated cross sections for low and intermediate energies of the incoming neutrino. The nuclear wave functions for the initial and final nuclear states are constructed in the context of the quasi-particle random phase approximation (QRPA) tested on the reproducibility of the low-lying energy spectrum. The results presented here refer to the isotopes Mo{sup 92}, Mo{sup 94}, Mo{sup 96}, Mo{sup 98} and Mo{sup 100}. These isotopes could play a significant role in supernova neutrino detection in addition to their use in double-beta and neutrinoless double-beta decay experiments (e.g. MOON, NEMO III)

  14. Pulsed CO laser for isotope separation of uranium

    SciTech Connect (OSTI)

    Baranov, Igor Y.; Koptev, Andrey V. [Rocket-Space Technics Department, Baltic State Technical University, 1, 1st Krasnoarmeyskaya st.,St. Petersburg, 190005 (Russian Federation)

    2012-07-30

    This article proposes a technical solution for using a CO laser facility for the industrial separation of uranium used in the production of fuel for nuclear power plants, employing a method of laser isotope separation of uranium with condensation repression in a free jet. The laser operation with nanosecond pulse irradiation can provide an acceptable efficiency in the separating unit and a high efficiency of the laser with the wavelength of 5.3 {mu}m. In the present work we also introduce a calculation model and define the parameters of a mode-locked CO laser with a RF discharge in the supersonic stream. The average pulsed CO laser power of 3 kW is sufficient for efficient industrial isotope separation of uranium in one stage.

  15. Elastic scattering of Beryllium isotopes near the Coulomb barrier

    SciTech Connect (OSTI)

    Di Pietro, A.; Figuera, P. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Amorini, F.; Fisichella, M.; Lattuada, M.; Musumarra, A.; Pellegriti, M. G.; Randisi, G.; Rizzo, F.; Santonocito, D.; Scalia, G.; Scuderi, V.; Strano, E.; Torresi, D. [Dipartimento di Fisica ed Astronomia Universita di Catania, Catania (Italy); INFN-Laboratori Nazionali del Sud, Catania (Italy); Papa, M. [INFN-Sezione di Catania, Catania (Italy); Acosta, L.; Martel, I.; Perez-Bernal, F. [Departamento de Fisica Aplicada Universidad de Huelva, Huelva (Spain); Borge, M. J. G.; Tengblad, O. [Instituto de Estructura de la Materia CSIC, Madrid (Spain)

    2011-10-28

    In this contribution, results of experiments performed with the three Beryllium isotopes {sup 9,10,11}Be on a medium mass {sup 64}Zn target, at a center of mass energy of {approx_equal}1.4 the Coulomb barrier, will be discussed. Elastic scattering angular distributions have been measured for the {sup 9,10}Be reactions. In the {sup 11}Be case the quasielastic scattering angular distribution was obtained. In the halo nucleus case, the angular distribution exhibit a non-Fresnel-type pattern with a strong damping of the Coulomb-nuclear interference peak. Moreover, it is found that the total reaction cross-section for the halo nucleus induced collision is more than double the ones extracted in the collisions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the {sup 11}Be case could be attributed to transfer and/or break-up events.

  16. Stable isotopes are a powerful way to describe and quantify trophic relationships in aquatic systems. Evaluating the ratios of carbon and nitrogen isotopes of consumers

    E-Print Network [OSTI]

    Lawrence, Deborah

    production in the Virginia Coast Reserve. #12;iii Results indicate that hydrogen isotope ratios can improve is not yet predictable. The application of hydrogen isotopes to marine food web studies warrants further and higher trophic levels. However, this method is only feasible when sources have distinct combinations

  17. FE ISOTOPE NUCLEOSYNTHESIS: CONSTRAINTS FROM FE ISOTOPIC ANALYSES OF PRESOLAR SILICATE GRAINS FROM ACFER 094. W. J. Ong and C. Floss. Laboratory for Space Sciences

    E-Print Network [OSTI]

    Floss, Christine

    FE ISOTOPE NUCLEOSYNTHESIS: CONSTRAINTS FROM FE ISOTOPIC ANALYSES OF PRESOLAR SILICATE GRAINS FROM information about fundamental astrophysical processes, such as stellar nucleosynthesis and galactic chemical evolution. Iron is of particular interest because of its importance in s-process nucleosynthesis. However

  18. 2008NaturePublishingGrouphttp://www.nature.com/naturechemicalbiology Quantitative exploration of the catalytic landscape

    E-Print Network [OSTI]

    Zhang, Jianzhi

    and Hyoscyamus muticus, we created a library of all possible residue combinations (29 ¼ 512) in the N. tabacum) a simplified set of naturally occurring mutations that interconvert a defined catalytic property for measur- ing the catalytic properties (recording the chemical readout) of the enzyme library. Therefore

  19. NOVEL CONCEPTS FOR ISOTOPIC SEPARATION OF 3HE/4HE

    SciTech Connect (OSTI)

    Roy, L.; Nigg, H.; Watson, H.

    2012-09-04

    The research outlined below established theoretical proof-of-concept using ab initio calculations that {sup 3}He can be separated from {sup 4}He by taking advantage of weak van der Waals interactions with other higher molecular weight rare gases such as xenon. To the best of our knowledge, this is the only suggested method that exploits the physical differences of the isotopes using a chemical interaction.

  20. FUEL CYCLE ISOTOPE EVOLUTION BY TRANSMUTATION DYNAMICS OVER MULTIPLE RECYCLES

    SciTech Connect (OSTI)

    Samuel Bays; Steven Piet; Amaury Dumontier

    2010-06-01

    Because all actinides have the ability to fission appreciably in a fast neutron spectrum, these types of reactor systems are usually not associated with the buildup of higher mass actinides: curium, berkelium and californium. These higher actinides have high specific decay heat power, gamma and neutron source strengths, and are usually considered as a complication to the fuel manufacturing and transportation of fresh recycled transuranic fuel. This buildup issue has been studied widely for thermal reactor fuels. However, recent studies have shown that the transmutation physics associated with "gateway isotopes" dictates Cm-Bk-Cf buildup, even in fast burner reactors. Assuming a symbiotic fuel relationship with light water reactors (LWR), Pu-242 and Am-243 are formed in the LWRs and then are externally fed to the fast reactor as part of its overall transuranic fuel supply. These isotopes are created much more readily in a thermal than in fast spectrum systems due to the differences in the fast fission (i.e., above the fission threshold for non-fissile actinides) contribution. In a strictly breeding fast reactor this dependency on LWR transuranics would not exist, and thus avoids the introduction of LWR derived gateway isotopes into the fast reactor system. However in a transuranic burning fast reactor, the external supply of these gateway isotopes behaves as an external driving force towards the creation and build-up of Cm-Bk-Cf in the fuel cycle. It was found that though the Cm-Bk-Cf concentration in the equilibrium fuel cycle is dictated by the fast neutron spectrum, the time required to reach that equilibrium concentration is dictated by recycle, transmutation and decay storage dynamics.