National Library of Energy BETA

Sample records for isotope geothermometry isotopic

  1. 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...

  2. Isotope Geothermometry | Open Energy Information

    Open Energy Info (EERE)

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  3. Category:Isotope Geothermometry | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank,CammackFLIR Jump to: navigation,Ground Gravity Survey JumpInjectivity

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. (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.

  16. 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.

  17. 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.

  18. 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)

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  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. Isotope Geothermometry At Lightning Dock Geothermal Area (Witcher, 2006) |

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy ResourcesOrder at 8, 13RenewableIrem GeothermalIslip Terrace,Open Energy

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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, ...

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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,...

  9. 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

  10. 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...

  11. 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.

  12. 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 Earths 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),morei.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 Earths 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

  13. 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.

  14. 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.

  15. 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...

  16. 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...

  17. 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

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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.

  6. [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.

  7. 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.

  8. 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.

  9. 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 -

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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).

  17. 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

  18. 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.

  19. Improved Geothermometry Through Multivariate Reaction Path Modeling...

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

    Improved Geothermometry Through Multivariate Reaction Path Modeling and Evaluation of Geomicrobiological Influences on Geochemical Temperature Indicators Improved Geothermometry...

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

    E-Print Network [OSTI]

    Meyers, Stephen R.

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

  1. 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

  2. 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.

  3. 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 ...

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. Bulk chemical and Hf??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 HfW isotopic consequences of incompletestyle affects the bulk chemical and isotopic outcomes ofto investigate the bulk chemical and isotopic consequences

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

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

    E-Print Network [OSTI]

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

  4. 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.

  5. 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...

  6. 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...

  7. 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 ...

  8. 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

  9. 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.

  10. 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.

  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. 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".

  9. Radioactive isotopes in Danish drinking water

    E-Print Network [OSTI]

    Radioactive isotopes in Danish drinking water Sven P. Nielsen Ris 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

  10. 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

  11. INTRODUCTION The oxygen isotopic compositions of minerals

    E-Print Network [OSTI]

    Gonzlez, 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

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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 testedmoreare 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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 ???Fr with reference to Fr 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.

  6. 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 ???Fr with reference to Fr 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.

  7. 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).

  8. 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.

  9. 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...

  10. 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:...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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,...

  2. 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:...

  3. 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...

  4. 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;...

  5. 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...

  6. 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

  7. 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...

  8. 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...

  9. 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...

  10. 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:...

  11. 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,...

  12. 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)

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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).

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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 Arar Mexico Isotopes of noble gases, CO2, H2O and Sr were measured in 10 geothermal wells and 8 hot springs, fumaroles and mud

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Mineral Selection for Multicomponent Equilibrium Geothermometry

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

    Plamer, C. D.; Ohly, S. R.; Smith, R. W.; Neupane, G.; McLing, T.; Mattson, E.

    2015-04-01

    Muliticomponent geothermometry requires knowledge of the mineral phases in the reservoir with which the geothermal fluids may be equilibrated.

  3. 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 ...

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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...

  9. 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 ...

  10. 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

  11. 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...

  12. 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 ...

  13. 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. ...

  14. 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.

  15. 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 etal. (2006) studied15:13011346 Kendall C, Elliott EM, Wankel SD (2007) Tracingmapping. Springer, Berlin Wankel SD, Kendall C, Francis CA,

  16. 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...

  17. 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 ...

  18. 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.

  19. 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.

  20. 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...

  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. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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)

  11. 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)

  12. 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).

  13. 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...

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Geothermometry At Nevada Test And Training Range Area (Sabin...

    Open Energy Info (EERE)

    Geothermometry At Nevada Test And Training Range Area (Sabin, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At...

  20. Geothermometry At Nw Basin & Range Region (Shevenell & De Rocher...

    Open Energy Info (EERE)

    Geothermometry At Nw Basin & Range Region (Shevenell & De Rocher, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At Nw...

  1. Geothermometry At Central Nevada Seismic Zone Region (Shevenell...

    Open Energy Info (EERE)

    Geothermometry At Central Nevada Seismic Zone Region (Shevenell & De Rocher, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry...

  2. 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.

  3. 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.

  4. 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.

  5. 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)

  6. 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

  7. 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 $\

  8. 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

  9. 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...

  10. 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...

  11. 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

  12. 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...

  13. 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...

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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, Universit de Lige, Alle du 6Aot B18, 4000 Lige Lead isotopic the effectiveness of using lead isotopic analysis in provenance studies, along with other analytical techniques

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

    E-Print Network [OSTI]

    Paris-Sud XI, Universit 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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).

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. (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

  10. 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.

  11. 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

  12. 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

  13. 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 1970s 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.

  14. 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

  15. 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 J 0 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

  16. 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

  17. 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.

  18. 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).

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  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. 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)

  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. 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.

  8. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Arruda, Lusa; Borges, Joo; Carmo, Fernando; Gonalves, Patrcia; Pereira, Rui; Pimenta, Mrio

    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.

  9. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Lusa Arruda; Fernando Baro; Joo Borges; Fernando Carmo; Patrcia Gonalves; Rui Pereira; Mrio 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.

  10. 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)

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. An overview of copper-laser development for isotope separation

    SciTech Connect (OSTI)

    Warner, B.E.

    1987-03-13

    We have developed a copper-laser pumped dye-laser system that addresses all of the requirements for atomic vapor laser isotope separation. The requirement for high average power for the laser system has led to the development of copper-laser chains with injection-locked oscillators and multihundred-watt amplifiers. By continuously operating the Laser Demonstration Facility, we gain valuable data for further upgrade and optimization.

  1. Upgrading scientific capabilities at the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    West, C.D.; Farrar, M.B.

    1997-07-14

    Following termination of the Advanced Neutron Source (ANS) Project, a program of upgrades to the Department of Energy`s High Flux Isotope Reactor (HFIR) was devised by a team of researchers and reactor operators and has been proposed to the department. HFIR is a multipurpose research reactor, commissioned in 1965, with missions in four nationally important areas: isotope production, especially transuranic isotopes; neutron scattering; neutron activation analysis; and irradiation testing of materials. For neutron scattering, there are two major enhancements and several smaller ones. The first is the installation of a small, hydrogen cold neutron source in one of the four existing beam tubes: because of the high reactor power, and the use of new design concepts developed for ANS, the cold source will be as bright as, or brighter than, the Institute Laue Langevin liquid deuterium vertical cold source, although space limitations mean that there will be far fewer cold beams and instruments at HFIR. This project is underway, and the cold source is expected to come on line following an extended shutdown in 1999 to replace the reactor`s beryllium reflector. The second major change proposed would put five thermal neutron guides at an existing beam port and construct a new guide hall to accommodate instruments on these very intense beams.

  2. Experimental Validation of the Multi-Isotope Process Monitor Concept

    SciTech Connect (OSTI)

    Orton, Christopher R.; Schwantes, Jon M.; Fraga, Carlos G.; Douglas, Matthew; Christensen, Richard

    2010-05-13

    Researchers from Pacific Northwest National Laboratory, in conjunction with personnel from The Ohio State University, are working to develop a system for monitoring spent nuclear fuel reprocessing facilities on-line, non-destructively, and in near-real-time. This method, known as the Multi-Isotope Process (MIP) Monitor, is based upon the measurement of distribution patterns of a suite of indicator (radioactive) isotopes present within particular process streams. Distribution patterns, monitored on-line by gamma spectrometry, are then compared in near-real-time to patterns representing "normal" process conditions using multivariate pattern recognition software. By targeting gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, high-resolution gamma detectors that may be easily deployed throughout the facility. In addition, utilization of a suite of radio-elements, including ones with multiple oxidation states, increases the likelihood that attempts to divert material via process manipulation would be detected. Proof-of-principle modeling exercises simulating changes in acid strength have been completed and the results are promising. Laboratory validation is currently under way and significant results are available. The latest experimental results, along with an overview of the method will be presented.

  3. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    SciTech Connect (OSTI)

    NONE

    1995-10-01

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department`s mission as stated in that document. ``The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.``

  4. Development of the laser isotope separation method (AVLIS) for obtaining weight amounts of highly enriched {sup 150}Nd isotope

    SciTech Connect (OSTI)

    Babichev, A P; Grigoriev, Igor' S; Grigoriev, A I; Dorovskii, A P; D'yachkov, Aleksei B; Kovalevich, S K; Kochetov, V A; Kuznetsov, V A; Labozin, Valerii P; Matrakhov, A V; Mironov, Sergei M; Nikulin, Sergei A; Pesnya, A V; Timofeev, N I; Firsov, Valerii A; Tsvetkov, G O; Shatalova, G G

    2005-10-31

    Results obtained at the first stage of development of the experimental technique for obtaining weight amounts of the highly enriched {sup 150}Nd isotope by laser photoionisation are presented. The vaporiser and the laser are designed, and various methods of irradiation of neodymium vapour and extraction of photoions are tested. The product yield {approx}40 mg h{sup -1} for the {approx}60% enrichment and 25 mg h{sup -1} for the {approx}65% enrichment is achieved for a vaporiser of length 27 cm. The cost of constructing the facility for preparing 50 kg of the {sup 150}Nd isotope, intended for determining the neutrino mass, is estimated. This estimate shows that the cost of production can be lowered by a factor of 5-7 compared to the electromagnetic method. (invited paper)

  5. Chemical, multi-isotopic (Li-B-Sr-U-H-O) and thermal characterization of Triassic formation waters from the Paris Basin

    E-Print Network [OSTI]

    Boyer, Edmond

    Chemical, multi-isotopic (Li-B-Sr-U-H-O) and thermal characterization of Triassic formation waters Torche fields in the centre of the Basin. The multi- isotope characterization of Triassic formation to characterize sandstone formation waters. Keywords: lithium isotopes, boron isotopes, strontium isotopes

  6. A ROBUST ABSOLUTE DETECTION EFFICIENCY CALIBRATION METHOD UTILIZING BETA/GAMMA COINCIDENCE SIGNATURES AND ISOTOPICALLY PURIFIED NEUTRON ACTIVATED RADIOXENON ISOTOPES

    SciTech Connect (OSTI)

    McIntyre, Justin I.; Cooper, Matthew W.; Ely, James H.; Haas, Derek A.; Schrom, Brian T.

    2012-09-21

    Efforts to calibrate the absolute efficiency of gas cell radiations detectors have utilized a number of methodologies which allow adequate calibration but are time consuming and prone to a host of difficult-to-determine uncertainties. A method that extrapolates the total source strength from the measured beta and gamma gated beta coincidence signal was developed in the 1960s and 1970s. It has become clear that it is possible to achieve more consistent results across a range of isotopes and a range of activities using this method. Even more compelling is the ease with which this process can be used on routine samples to determine the total activity present in the detector. Additionally, recent advances in the generation of isotopically pure radioxenon samples of Xe-131m, Xe-133, and Xe-135 have allowed these measurement techniques to achieve much better results than would have been possible before when using mixed isotopic radioxenon source. This paper will discuss the beta/gamma absolute detection efficiency technique that utilizes several of the beta-gamma decay signatures to more precisely determine the beta and gamma efficiencies. It will than compare these results with other methods using pure sources of Xe-133, Xe-131m, and Xe-135 and a Xe-133/Xe-133m mix.

  7. Yucca Mountain Area Saturated Zone Dissolved Organic Carbon Isotopic Data

    SciTech Connect (OSTI)

    Thomas, James; Decker, David; Patterson, Gary; Peterman, Zell; Mihevc, Todd; Larsen, Jessica; Hershey, Ronald

    2007-06-25

    Groundwater samples in the Yucca Mountain area were collected for chemical and isotopic analyses and measurements of water temperature, pH, specific conductivity, and alkalinity were obtained at the well or spring at the time of sampling. For this project, groundwater samples were analyzed for major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC). The U.S. Geological Survey (USGS) performed all the fieldwork on this project including measurement of water chemistry field parameters and sample collection. The major ions dissolved in the groundwater, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC) were analyzed by the USGS. All preparation and processing of samples for DOC carbon isotopic analyses and geochemical modeling were performed by the Desert Research Institute (DRI). Analysis of the DOC carbon dioxide gas produced at DRI to obtain carbon-13 and carbon-14 values was conducted at the University of Arizona Accelerator Facility (a NSHE Yucca Mountain project QA qualified contract facility). The major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of DIC were used in geochemical modeling (NETPATH) to determine groundwater sources, flow paths, mixing, and ages. The carbon isotopes of DOC were used to calculate groundwater ages that are independent of DIC model corrected carbon-14 ages. The DIC model corrected carbon-14 calculated ages were used to evaluate groundwater travel times for mixtures of water including water beneath Yucca Mountain. When possible, groundwater travel times were calculated for groundwater flow from beneath Yucca Mountain to down gradient sample sites. DOC carbon-14 groundwater ages were also calculated for groundwaters in the Yucca Mountain area. When possible, groundwater travel times were estimated for groundwater flow from beneath Yucca Mountain to down gradient groundwater sample sites using the DOC calculated groundwater ages. The DIC calculated groundwater ages were compared with DOC calculated groundwater ages and both of these ages were compared to travel times developed in ground-water flow and transport models. If nuclear waste is stored in Yucca Mountain, the saturated zone is the final barrier against the release of radionuclides to the environment. The most recent rendition of the TSPA takes little credit for the presence of the saturated zone and is a testament to the inadequate understanding of this important barrier. If radionuclides reach the saturated zone beneath Yucca Mountain, then there is a travel time before they would leave the Yucca Mountain area and flow down gradient to the Amargosa Valley area. Knowing how long it takes groundwater in the saturated zone to flow from beneath Yucca Mountain to down gradient areas is critical information for potential radionuclide transport. Radionuclide transport in groundwater may be the quickest pathway for radionuclides in the proposed Yucca Mountain repository to reach land surface by way of groundwater pumped in Amargosa Valley. An alternative approach to ground-water flow and transport models to determine the travel time of radionuclides from beneath Yucca Mountain to down gradient areas in the saturated zone is by carbon-14 dating of both inorganic and organic carbon dissolved in the groundwater. A standard method of determining ground-water ages is to measure the carbon-13 and carbon-14 of DIC in the groundwater and then correct the measured carbon-14 along a flow path for geochemical reactions that involve carbon containing phases. These geochemical reactions are constrained by carbon-13 and isotopic fractionations. Without correcting for geochemical reactions, the ground-water ages calculated from only the differences in carbon-14 measured along a flow path (assuming the decrease in carbon-14 is due strictly to radioactive decay) could be tens of thousands of years too old. The computer program NETPATH, developed by the USGS, is the best geochemical program for correcting carbon-14 activities for geochemical r

  8. Resonance ionization laser ion sources for on-line isotope separators...

    Office of Scientific and Technical Information (OSTI)

    Resonance ionization laser ion sources for on-line isotope separators (invited) Citation Details In-Document Search Title: Resonance ionization laser ion sources for on-line...

  9. A Sr-Isotopic Comparison Between Thermal Waters, Rocks, And Hydrotherm...

    Open Energy Info (EERE)

    Caldera, California Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Sr-Isotopic Comparison Between Thermal Waters, Rocks, And Hydrothermal...

  10. Stable-Isotope Studies Of Rocks And Secondary Minerals In A Vapor...

    Open Energy Info (EERE)

    & Epstein, 1992) Isotopic Analysis At Geysers Area (Lambert & Epstein, 1992) Petrography Analysis At Geysers Area (Lambert & Epstein, 1992) Areas (1) Geysers Area Regions...

  11. 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.

  12. Neutron rich Carbon and Oxygen isotopes with an odd number of neutrons

    E-Print Network [OSTI]

    Benoit Laurent; Nicole Vinh Mau

    2013-04-02

    We describe odd isotopes as formed of a core plus one neutron. We have calculated the modification of single neutron energies brought by couplings of the neutron with collective $2^+$ phonons in the cores. The results reproduce very well the inversion of $2s$ and $1d_{5/2}$ shells in carbon isotopes up to $^{19}$C while in oxygen isotopes the correction is also large but do not show any inversion in agreement with experiments. The calculated energies are close to the experimental ones in both series of isotopes except in $^{21}$C for the $2s$ state for which our coupling is too weak.

  13. A Mass Spectrometry Study of Isotope Separation in the Laser Plume

    E-Print Network [OSTI]

    Suen, Timothy Wu

    2012-01-01

    code for determining plutonium isotopic abundances. volumefor the Characterization of Plutonium and Highly EnrichedKoch, Origin determination of plutonium material in nuclear

  14. Isotope fractionation in surface ionization ion source of alkaline-earth iodides

    SciTech Connect (OSTI)

    Suzuki, T.; Kanzaki, C.; Nomura, M.; Fujii, Y.

    2012-02-15

    The relationship between the isotope fractionation of alkaline-earth elements in the surface ionization ion source and the evaporation filament current, i.e., filament temperature, was studied. It was confirmed that the isotope fractionation depends on the evaporation filament temperature; the isotope fractionation in the case of higher temperature of filament becomes larger. The ionization and evaporation process in the surface ionization ion source was discussed, and it was concluded that the isotope fractionation is suppressed by setting at the lower temperature of evaporation filament because the dissociations are inhibited on the evaporation filament.

  15. Stable isotopes of authigenic minerals in variably-saturated fractured tuff

    SciTech Connect (OSTI)

    Weber, D.S.; Evans, D.D.

    1988-11-01

    Identifying stable isotope variation and mineralogical changes in fractured rock may help establish the history of climatic and geomorphological processes that might affect the isolation properties of a waste repository site. This study examines the use of the stable isotope ratios of oxygen ({sup 18}O/{sup 16}O) and carbon ({sup 13}C/{sup 12}C) in authigenic minerals as hydrogeochemical tools tracing low-temperature rock-water interaction in variably-saturated fractured stuff. Isotopic compositions of fracture-filling and rock matrix minerals in the Apache Leap tuff, near Superior, Arizona were concordant with geothermal temperatures and in equilibrium with water isotopically similar to present-day meteoric water and groundwater. Oxygen and carbon isotope ratios of fracture-filling, in unsaturated fractured tuff, displayed an isotopic gradient believed to result from near-surface isotopic enrichment due to evaporation rather than the effects of rock-water interaction. Oxygen isotope ratios of rock matrix opal samples exhibited an isotopic gradient believed to result from, leaching and reprecipitation of silica at depth. Methods and results can be used to further define primary flowpaths and the movement of water in variably-saturated fractured rock. 71 refs., 23 figs., 3 tabs.

  16. 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,

  17. 2013 Workshop on Isotope Federal Supply and Demand | U.S. DOE...

    Office of Science (SC) Website

    of isotopes from a Federal perspective, in various areas including homeland defense, medicine, agriculture, and basic and applied research. Participants will engage in discussions...

  18. 2014 Workshop on Isotope Federal Supply and Demand | U.S. DOE...

    Office of Science (SC) Website

    of isotopes from a Federal perspective, in various areas including homeland defense, medicine, agriculture, and basic and applied research. Participants will engage in discussions...

  19. 2015 Workshop on Isotope Federal Supply and Demand | U.S. DOE...

    Office of Science (SC) Website

    of isotopes from a Federal perspective, in various areas including homeland defense, medicine, agriculture, and basic and applied research. Participants will engage in discussions...

  20. 2012 Workshop on Isotope Federal Supply and Demand | U.S. DOE...

    Office of Science (SC) Website

    of isotopes from a Federal perspective, in various areas including homeland defense, medicine, agriculture, and basic and applied research. Participants will engage in discussions...

  1. CARBON ISOTOPE AND ISOTOPOMER FRACTIONATION IN COLD DENSE CLOUD CORES

    SciTech Connect (OSTI)

    Furuya, Kenji; Aikawa, Yuri [Department of Earth and Planetary Sciences, Kobe University, Kobe 657-8501 (Japan); Sakai, Nami; Yamamoto, Satoshi, E-mail: furuya@stu.kobe-u.ac.jp [Department of Physics and Research Center for the Early Universe, University of Tokyo, Bunkyo-ku, Tokyo 113-003 (Japan)

    2011-04-10

    We construct a gas-grain chemical network model which includes carbon isotopes ({sup 12}C and {sup 13}C) with an emphasis on isotopomer-exchange reactions. Temporal variations of molecular abundances, the carbon isotope ratios ({sup 12}CX/{sup 13}CX), and the isotopomer ratios ({sup 12}C{sup 13}CX/{sup 13}C{sup 12}CX) of CCH and CCS in cold dense cloud cores are investigated by numerical calculations. We confirm that the isotope ratios of molecules, both in the gas phase and grain surfaces, are significantly different depending on whether the molecule is formed from the carbon atom (ion) or the CO molecule. Molecules formed from carbon atoms have CX/{sup 13}CX ratios greater than the elemental abundance ratio of [{sup 12}C/{sup 13}C]. On the other hand, molecules formed from CO molecules have CX/{sup 13}CX ratios smaller than the [{sup 12}C/{sup 13}C] ratio. We reproduce the observed C{sup 13}CH/{sup 13}CCH ratio in TMC-1, if the isotopomer-exchange reaction, {sup 13}CCH + H {r_reversible} C{sup 13}CH + H + 8.1 K, proceeds with the forward rate coefficient k{sub f} > 10{sup -11} cm{sup 3} s{sup -1}. However, the C{sup 13}CS/{sup 13}CCS ratio is lower than that observed in TMC-1. We then assume the isotopomer-exchange reaction catalyzed by the H atom, {sup 13}CCS + H {r_reversible} C{sup 13}CS + H + 17.4 K. In the model with this reaction, we reproduce the observed C{sup 13}CS/{sup 13}CCS, CCS/C{sup 13}CS, and CCS/{sup 13}CCS ratios simultaneously.

  2. Thermal Neutron Capture Cross Sections of the PalladiumIsotopes

    SciTech Connect (OSTI)

    Firestone, R.B.; Krticka, M.; McNabb, D.P.; Sleaford, B.; Agvaanluvsan, U.; Belgya, T.; Revay, Zs.

    2006-07-17

    Precise gamma-ray thermal neutron capture cross sectionshave been measured at the Budapest Reactor for all elements withZ=1-83,92 except for He and Pm. These measurements and additional datafrom the literature been compiled to generate the Evaluated Gamma-rayActivation File (EGAF), which is disseminated by LBNL and the IAEA. Thesedata are nearly complete for most isotopes with Z<20 so the totalradiative thermal neutron capture cross sections can be determineddirectly from the decay scheme. For light isotopes agreement with therecommended values is generally satisfactory although large discrepanciesexist for 11B, 12,13C, 15N, 28,30Si, 34S, 37Cl, and 40,41K. Neutroncapture decay data for heavier isotopes are typically incomplete due tothe contribution of unresolved continuum transitions so only partialradiative thermal neutron capture cross sections can be determined. Thecontribution of the continuum to theneutron capture decay scheme arisesfrom a large number of unresolved levels and transitions and can becalculated by assuming that the fluctuations in level densities andtransition probabilities are statistical. We have calculated thecontinuum contribution to neutron capture decay for the palladiumisotopes with the Monte Carlo code DICEBOX. These calculations werenormalized to the experimental cross sections deexciting low excitationlevels to determine the total radiative thermal neutron capture crosssection. The resulting palladium cross sections values were determinedwith a precision comparable to the recommended values even when only onegamma-ray cross section was measured. The calculated and experimentallevel feedings could also be compared to determine spin and parityassignments for low-lying levels.

  3. 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.

  4. Stable water isotope simulation by current land-surface schemes:Results of IPILPS phase 1

    SciTech Connect (OSTI)

    Henderson-Sellers, A.; Fischer, M.; Aleinov, I.; McGuffie, K.; Riley, W.J.; Schmidt, G.A.; Sturm, K.; Yoshimura, K.; Irannejad, P.

    2005-10-31

    Phase 1 of isotopes in the Project for Intercomparison of Land-surface Parameterization Schemes (iPILPS) compares the simulation of two stable water isotopologues ({sup 1}H{sub 2} {sup 18}O and {sup 1}H{sup 2}H{sup 16}O) at the land-atmosphere interface. The simulations are off-line, with forcing from an isotopically enabled regional model for three locations selected to offer contrasting climates and ecotypes: an evergreen tropical forest, a sclerophyll eucalypt forest and a mixed deciduous wood. Here we report on the experimental framework, the quality control undertaken on the simulation results and the method of intercomparisons employed. The small number of available isotopically-enabled land-surface schemes (ILSSs) limits the drawing of strong conclusions but, despite this, there is shown to be benefit in undertaking this type of isotopic intercomparison. Although validation of isotopic simulations at the land surface must await more, and much more complete, observational campaigns, we find that the empirically-based Craig-Gordon parameterization (of isotopic fractionation during evaporation) gives adequately realistic isotopic simulations when incorporated in a wide range of land-surface codes. By introducing two new tools for understanding isotopic variability from the land surface, the Isotope Transfer Function and the iPILPS plot, we show that different hydrological parameterizations cause very different isotopic responses. We show that ILSS-simulated isotopic equilibrium is independent of the total water and energy budget (with respect to both equilibration time and state), but interestingly the partitioning of available energy and water is a function of the models' complexity.

  5. 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.

  6. New experimental limits on the alpha decays of lead isotopes

    E-Print Network [OSTI]

    J. W. Beeman; F. Bellini; L. Cardani; N. Casali; S. Di Domizio; E. Fiorini; L. Gironi; S. S. Nagorny; S. Nisi; F. Orio; L. Pattavina; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; C. Tomei; M. Vignati

    2012-12-12

    For the first time a PbWO4 crystal was grown using ancient Roman lead and it was run as a cryogenic detector. Thanks to the simultaneous and independent read-out of heat and scintillation light, the detector was able to discriminate beta/gamma interactions with respect to alpha particles down to low energies. New more stringent limits on the alpha decays of the lead isotopes are presented. In particular a limit of T_{1/2} > 1.4*10^20 y at a 90% C.L. was evaluated for the alpha decay of 204Pb to 200Hg.

  7. Estimation of neutron-induced spallation yields of krypton isotopes

    SciTech Connect (OSTI)

    Karol, P.J.; Tobin, M.J.; Shibata, S.

    1983-10-01

    A procedure is outlined for estimating cross sections for neutron-induced spallation products relative to those for proton-induced reactions. When combined with known proton spallation systematics, it is demonstrated that cumulative yields for cosmogenically-important stable /sup 84/Kr and /sup 86/Kr isotopes are approx.1.4 and approx.2.8 times greater, respectively, for incident neutrons compared to protons at 0.2< or =E< or =3.0 GeV for nearby medium mass targets. Yields for lighter kryptons are relatively insensitive to the identity of the incident nucleon.

  8. Thermal Neutron Capture Cross Sections Of The Palladium Isotopes

    SciTech Connect (OSTI)

    Firestone, R. B. [Lawrence Berkeley National Laboratory Berkeley CA 94720 (United States); Krtiaka, M. [Faculty of Mathematics and Physics, Charles University V Holesovickach 2, CZ-180 00 Prague 8 (Czech Republic); McNabb, D. P.; Sleaford, B.; Agvaanluvsan, U. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Belgya, T.; Revay, Zs. [Institute of Isotope and Surface Chemistry H-1525, Budapest (Hungary)

    2006-03-13

    We have measured precise thermal neutron capture {gamma}-ray cross sections cry for all stable Palladium isotopes with the guided thermal neutron beam from the Budapest Reactor. The data were compared with other data from the literature and have been evaluated into the Evaluated Gamma-ray Activation File (EGAF). Total radiative neutron capture cross-sections {sigma}{gamma} can be deduced from the sum of transition cross sections feeding the ground state of each isotope if the decay scheme is complete. The Palladium isotope decay schemes are incomplete, although transitions deexciting low-lying levels are known for each isotope. We have performed Monte Carlo simulations of the Palladium thermal neutron capture deexcitation schemes using the computer code DICEBOX. This program generates level schemes where levels below a critical energy Ecrit are taken from experiment, and those above Ecrit are calculated by a random discretization of an a priori known level density formula {rho}(E,J{pi}). Level de-excitation branching intensities are taken from experiment for levels below Ecrit the capture state, or calculated for levels above Ecrit assuming an a priori photon strength function and applying allowed selection rules and a Porter-Thomas distribution of widths. The advantage of this method is that calculational uncertainties can be investigated systematically. Calculated feeding to levels below Ecrit can be normalized to the measured cross section deexciting those levels to determine the total radiative neutron cross-section {sigma}{gamma}. In this paper we report the cross section measurements {sigma}{gamma}[102Pd(n,{gamma})]=0.9{+-}0.3 b, {sigma}{gamma}[104Pd(n,{gamma})=0.61{+-}0.11 b, {sigma}{gamma}[105Pd(n,{gamma})]=2.1.1{+-}1.5 b, {sigma}{gamma}[106Pd(n,{gamma})]=0.36{+-}0.05 b, {sigma}{gamma}[108Pd(n,{gamma})(0)]=7.6{+-}0.6 b, {sigma}{gamma}[108Pd(n,{gamma})(189)]=0.185{+-}0.011 b, and {sigma}{gamma}[110Pd(n,{gamma})]=0.10{+-}0.03 b. We have also determined from our statistical calculations that the neutron capture states in 107Pd are best described as 2+[59(4)%]+3+[41(4)%]. Agreement with literature values was excellent in most cases. We found significant discrepancies between our results for 102Pd and 110Pd and earlier values that could be resolved by re-evaluation of the earlier results.

  9. Oxygen and hydrogen isotopes in thermal waters at Zunil, Guatemala

    SciTech Connect (OSTI)

    Fournier, R.O.; Hanshaw, B.B.; Urrutia Sole, J.F.

    1982-10-01

    Enthalpy-chloride relations suggest that a deep reservoir exists at Zunil with a temperature near 300/sup 0/C. Water from that reservoir moves to shallower and cooler local reservoirs, where it mixes with diluted water and then attains a new water-rock chemical equilibrium. This mixed water, in turn, generally is further diluted before being discharged from thermal springs. The stable-isotopic composition of the thermal water indicates that recharge for the deep water at Zunil comes mainly from local sources. The presence of measurable tritium, which suggests that the deep water has been underground about 20 to 30 years, also indicates a local source for the recharge.

  10. Consistency test of neutrinoless double beta decay with one isotope

    E-Print Network [OSTI]

    Michael Duerr; Manfred Lindner; Kai Zuber

    2011-11-17

    We discuss a consistency test which makes it possible to discriminate unknown nuclear background lines from neutrinoless double beta decay with only one isotope. By considering both the transition to the ground state and to the first excited $0^+$ state, a sufficiently large detector can reveal if neutrinoless double beta decay or some other nuclear physics process is at work. Such a detector could therefore simultaneously provide a consistency test for a certain range of Majorana masses and be sensitive to lower values of the effective Majorana mass.

  11. Consistency test of neutrinoless double beta decay with one isotope

    SciTech Connect (OSTI)

    Duerr, Michael; Lindner, Manfred [Max-Planck-Institut fuer Kernphysik, Postfach 10 39 80, 69029 Heidelberg (Germany); Zuber, Kai [Technical University Dresden, Institut fuer Kern- und Teilchenphysik, 01069 Dresden (Germany)

    2011-11-01

    We discuss a consistency test which makes it possible to discriminate unknown nuclear background lines from neutrinoless double beta decay with only one isotope. By considering both the transition to the ground state and to the first excited 0{sup +} state, a sufficiently large detector can reveal if neutrinoless double beta decay or some other nuclear physics process is at work. Such a detector could therefore simultaneously provide a consistency test for a certain range of Majorana masses and be sensitive to lower values of the effective Majorana mass .

  12. Tunable dye laser amplifier chain for laser isotope separation

    SciTech Connect (OSTI)

    Grigoriev, Igor' S; D'yachkov, Aleksei B; Labozin, Valerii P; Mironov, Sergei M; Nikulin, Sergei A; Firsov, Valerii A

    2004-05-31

    A tunable dye laser amplifier chain developed for experiments on atomic vapour laser isotope separation (AVLIS) is described. The system, pumped by copper vapour lasers, consists of a master oscillator and an amplifier stage including a preamplifier and three main amplifiers working in the saturation mode. The master oscillator of the stage is a dye laser with a grazing incidence diffraction grating. Longitudinal pumping of the amplifiers is used. The efficiency of the main amplifiers is 50 % - 55 %. The average power of laser radiation at the output of the last amplifier is 100 W. (lasers. amplifiers)

  13. Categorical Exclusion 4577: Lithium Isotope Separation & Enrichment Technologies

    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 OutreachProductswsicloudwsiclouddenDVA N C E D B LReportsDeterminatIonFornl Project Title: SortLithium Isotope

  14. Category:Isotopic Analysis- Rock | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmentalBowerbank,CammackFLIR Jump to: navigation,Ground Gravity SurveyIsotopic Analysis-

  15. Isotope production agreement benefits medical patients | National Nuclear

    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 andSecurity

  16. Effect of 13C isotope doping on the optical phonon modes in graphene: Localization and Raman spectroscopy

    E-Print Network [OSTI]

    Rodriguez-Nieva, J. F.

    The effect of [superscript 13]C isotope impurities on the phonon properties of graphene is discussed theoretically. We calculated the values of the phonon lifetimes due to isotope impurity scattering for all values of ...

  17. Evolution of Anthropogenic Pb and Pb isotopes in the deep North Atlantic Ocean and the Indian Ocean

    E-Print Network [OSTI]

    Lee, Jong-Mi, Ph. D. Massachusetts Institute of Technology

    2013-01-01

    Pb and Pb isotopes in the ocean have varied on decadal to centennial time scales due to anthropogenic Pb inputs. Thus, tracing the temporal variation of Pb and Pb isotopes in the ocean provides information on the major ...

  18. Lithium isotopes in global mid-ocean ridge basalts Paul B. Tomascak a,*, Charles H. Langmuir b

    E-Print Network [OSTI]

    Langmuir, Charles H.

    Lithium isotopes in global mid-ocean ridge basalts Paul B. Tomascak a,*, Charles H. Langmuir b January 2008 Abstract The lithium isotope compositions of 30 well-characterized samples of glassy lavas

  19. Deglacial Neodymium Isotopic Ratios in the Florida Straits and the Response of Intermediate Waters to Reduced Meridional Overturning Circulation

    E-Print Network [OSTI]

    Franklin, Alyssa L.

    2010-07-14

    studied using conventional paleo-circulation tracers. In this study we measure Nd isotopes in sediments of the Florida Straits to investigate this discrepancy. Nd isotope ratios in the authigenic component of marine sediments are thought to be a reliable...

  20. Identification of sources of lead exposure in French children by lead isotope analysis: a cross-

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Identification of sources of lead exposure in French children by lead isotope analysis: a cross://www.ehjournal.net/content/10/1/75 (28 August 2011) #12;RESEARCH Open Access Identification of sources of lead exposure in French children by lead isotope analysis: a cross- sectional study Youssef Oulhote1,2,3* , Barbara Le Bot

  1. "Stable Water Isotope Intercomparison Group" Summary Report from the 1st

    E-Print Network [OSTI]

    Noone, David

    of a consortium of international well-known scientists with expertise on both stable water isotope modelling the linkage between the stable water isotope modelling community and the International Atomic Energy Agency quantity within a closed "model world" where all other relevant climate parameters are known, too

  2. Major Evolutionary Trends in Hydrogen Isotope Fractionation of Vascular Plant Leaf Waxes

    E-Print Network [OSTI]

    Edwards, Erika J.

    Major Evolutionary Trends in Hydrogen Isotope Fractionation of Vascular Plant Leaf Waxes Li Gao1 States of America Abstract Hydrogen isotopic ratios of terrestrial plant leaf waxes (dD) have been widely in leaf wax dD values in different terrestrial vascular plants are still poorly understood, hampering

  3. EIS-0136: Special Isotope Separation Project Idaho National Engineering Laboratory, Idaho Falls, Idaho

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this EIS to provide environmental input to the decision to construct the Special Isotope Separation Project, which would allow for the processing of existing fuel-grade plutonium into weapons-grade plutonium using the Atomic Laser Isotope Separation process.

  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. Late Quaternary variability of sedimentary nitrogen isotopes in the eastern South Pacific Ocean

    E-Print Network [OSTI]

    Demouchy, Sylvie

    Late Quaternary variability of sedimentary nitrogen isotopes in the eastern South Pacific Ocean), Late Quaternary variability of sedimentary nitrogen isotopes in the eastern South Pacific Ocean) in the water columns of the Arabian Sea (AS) and the eastern North and South Pacific oceans (ENP; ESP) holds

  6. From the subtropics to the central equatorial Pacific Ocean: Neodymium isotopic composition and rare earth element

    E-Print Network [OSTI]

    Boyer, Edmond

    From the subtropics to the central equatorial Pacific Ocean: Neodymium isotopic composition, and S. Cravatte (2013), From the subtropics to the central equatorial Pacific Ocean: Neodymium isotopic waters (112 samples) in the Southern Tropical Pacific. The relatively detailed picture of these tracer

  7. Thorium isotopes in the western Mediterranean Sea: an insight into the marine particle dynamics

    E-Print Network [OSTI]

    Coppola, Laurent

    Thorium isotopes in the western Mediterranean Sea: an insight into the marine particle dynamics M rights reserved. Keywords: thorium; isotopes; sea water; particles; sedimentation; Mediterranean Sea 1 physical, chemical and biological processes and sometimes non-steady-state condi- tions [1^4]. Thorium

  8. Chemical and isotopic analysis of hydrocarbon gas at trace levels Methodology and results

    E-Print Network [OSTI]

    Chappellaz, Jrme

    -C-IRMS) permits measurement of relative proportions of gaseous hydrocarbon (CH4 to C4H10) and CO2 of hydrocarbons (from 1 ppm to 1000 ppm), accurate measurement of isotope ratios is often impossible dueChemical and isotopic analysis of hydrocarbon gas at trace levels Methodology and results Yvon

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

    E-Print Network [OSTI]

    Evans, Michael N.

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

  10. Constraints on origin and evolution of Red Sea brines from helium and argon isotopes

    E-Print Network [OSTI]

    Aeschbach-Hertig, Werner

    mantle production ratio. In the Kebrit Deep, located in the northern Red Sea, we found a helium excessConstraints on origin and evolution of Red Sea brines from helium and argon isotopes Gisela, the Discovery and the Kebrit Deep, were sampled and analyzed for helium and argon isotopes. We identified two

  11. Isotopes in Environmental and Health Studies Vol. 45, No. 3, September 2009, 220230

    E-Print Network [OSTI]

    in terrestrial ecosystems to elucidate information on various spatial and temporal scales. While most isotopic of ecosystem development processes and provide the basis for further isotopic studies at a site or within studies target individual ecosystem components or processes, research has shown that ecosystem

  12. Variations in the diet of introduced Norway rats (Rattus norvegicus) inferred using stable isotope analysis

    E-Print Network [OSTI]

    Variations in the diet of introduced Norway rats (Rattus norvegicus) inferred using stable isotope predators; island ecosystem conservation; stable isotope analysis; Norway rats; diet. Correspondence Heather of introduced Norway rats Rattus norvegicus has raised concerns for the fate of the large least auklet Aethia

  13. Hydrogen isotope fractionation in freshwater and marine algae: II. Temperature and nitrogen limited growth rate effects

    E-Print Network [OSTI]

    Sachs, Julian P.

    Hydrogen isotope fractionation in freshwater and marine algae: II. Temperature and nitrogen limited Accepted 7 November 2008 Available online 17 November 2008 a b s t r a c t Zhang and Sachs [Hydrogen. Introduction Hydrogen isotope ratios in plant and algal lipids from sediments are increasingly used

  14. Carbon kinetic isotope effects on the hydration of carbon dioxide and the dehydration of bicarbonate ion

    SciTech Connect (OSTI)

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

    1984-09-05

    /sup 13/C kinetic isotope effects on the hydration of CO/sub 2/ and the dehydration of HCO/sub 3//sup -/ in aqueous solution have been measured by rapid removal of the product and conversion to an isotopically stable form, followed by isotope-ratio analysis. The isotope effect on hydration is k/sup 12//k/sup 13/ = 1.0069 +/- 0.0003 at 24/sup 0/C. The isotope effect on dehydration is 1.0147 +/- 0.0007. The ratio of these two values gives an equilibrium isotope effect of K/sup 12//K/sup 13/ = 1.0077, in good agreement with previously measured values. The small magnitudes of the kinetic isotope effects indicate that the transition state for conversion of HCO/sub 3//sup -/ to CO/sub 2/ is very similar to that of HCO/sub 3//sup -/. This information together with previously measured solvent isotope effects indicates that the mechanism of HCO/sub 3//sup -/ dehydration probably involves general-acid-catalyzed donation of a proton from H/sub 3/O/sup +/ to the departing oxygen, rather than unimolecular decomposition of the zwitterion H/sub 2/O/sup +/-CO/sub 2//sup -/ in the rate-determining step. 21 references, 2 figures.

  15. Mantle source provinces beneath the Northwestern USA delimited by helium isotopes in young basalts

    E-Print Network [OSTI]

    Graham, David W.

    phenocrysts in basalts from the eastern Snake River Plain (SRP), the Owyhee Plateau (OP) and the Oregon High: Received 17 April 2008 Accepted 11 December 2008 Available online 31 December 2008 Keywords: Snake River Plain High Lava Plains Yellowstone helium isotopes mantle plume We report new He, Nd and Sr isotope

  16. 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

  17. Consequences of a Rapid Cellulose Extraction Technique for Oxygen Isotope and Radiocarbon

    E-Print Network [OSTI]

    Schrag, Daniel

    Consequences of a Rapid Cellulose Extraction Technique for Oxygen Isotope and Radiocarbon Analyses isotope analyses to investigate the purity of cellulose extracted from wood using a rapid processing and plant physiological processes has typically focused on the R-cellulose component of wood, necessitating

  18. High-precision optical measurements of 13 isotope ratios in organic compounds at

    E-Print Network [OSTI]

    Zare, Richard N.

    range with an average precision of 0.95 and 0.67 for ethane and propane, respec- tively. The calibrated accuracy for methane, ethane, and propane is within 3 of the values determined using isotope ratio mass-down spectroscopy combustion isotopic ratio It is often taught in beginning chemistry classes that the atoms

  19. Formation of ozone: Metastable states and anomalous isotope effect Dmitri Babikov,a)

    E-Print Network [OSTI]

    Reid, Scott A.

    Formation of ozone: Metastable states and anomalous isotope effect Dmitri Babikov,a) Brian K for an anomalous isotope effect in ozone formation is given in terms of the energy transfer mechanism, where the metastable states of ozone are formed first, and then stabilized by collisions with other atoms. Unusual

  20. Carbon dioxide-water oxygen isotope fractionation factor using chlorine trifluoride and guanidine hydrochloride techniques

    SciTech Connect (OSTI)

    Dugan, J.P. Jr.; Borthwick, J.

    1986-12-01

    A new value for the CO/sub 2/-H/sub 2/O oxygen isotope fractionation factor of 1.04145 +/- 0.000 15 (2sigma) has been determined. The data have been normalized to the V-SMOW/V-SLAP scale and were obtained by measuring isotopic compositions with the guanidine hydrochloride and chlorine trifluoride techniques.

  1. Alpha-emitting isotopes and chromium in a coastal California aquifer Jill N. Densmore a,

    E-Print Network [OSTI]

    .epa.gov/drink/contaminants/#List, accessed December 3, 2013). Understanding the chemistry and distribution of isotopes within the uranium) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium

  2. Liquid-phase thermal diffusion isotope separation apparatus and method having tapered column

    DOE Patents [OSTI]

    Rutherford, W.M.

    1985-12-04

    A thermal diffusion counterflow method and apparatus for separating isotopes in solution in which the solution is confined in a long, narrow, vertical slit which tapers from bottom to top. The variation in the width of the slit permits maintenance of a stable concentration distribution with relatively long columns, thus permitting isotopic separation superior to that obtained in the prior art.

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

    E-Print Network [OSTI]

    Wu, Zhigang

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

  4. Lithium isotopic composition and concentration of the deep continental crust Fang-Zhen Teng a,

    E-Print Network [OSTI]

    Mcdonough, William F.

    Lithium isotopic composition and concentration of the deep continental crust Fang-Zhen Teng a April 2008 Accepted 5 June 2008 Editor: B. Bourdon Keywords: Lithium Isotope fractionation Deep. Lithium concentrations of granulite xenoliths also vary widely (0.5 to 21 ppm) and are, on average, lower

  5. Limited lithium isotopic fractionation during progressive metamorphic dehydration in metapelites: A case study

    E-Print Network [OSTI]

    Mcdonough, William F.

    Limited lithium isotopic fractionation during progressive metamorphic dehydration in metapelites-zone metamorphism far removed from the pluton to partially melted rocks adjacent to the pluton. Lithium on the aureole scale. Published by Elsevier B.V. Keywords: Lithium; Isotope fractionation; Metamorphic

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

    E-Print Network [OSTI]

    Zeebe, Richard E.

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

  7. Nucleosynthetic osmium isotope anomalies in acid leachates of the Murchison meteorite

    E-Print Network [OSTI]

    Nucleosynthetic osmium isotope anomalies in acid leachates of the Murchison meteorite L. Reisberg a of the total leachable osmium (weighted average of the leachates) is close to that of bulk chondrites in meteorites in sufficient quantities to influence the Os isotopic compositions of the leachates. Nevertheless

  8. Preservation and detection of microstructural and taxonomic correlations in the carbon isotopic compositions

    E-Print Network [OSTI]

    Meyers, Stephen R.

    published carbonate carbon isotope data can be used to estimate the d13 C of the original dissolvedPreservation and detection of microstructural and taxonomic correlations in the carbon isotopic of Earth and Space Sciences, Center for the Study of Evolution and the Origin of Life, and Molecular

  9. c0011 Carbon Isotope Stratigraphy M.R. Saltzman and E. Thomas

    E-Print Network [OSTI]

    Chapter 11 c0011 Carbon Isotope Stratigraphy M.R. Saltzman and E. Thomas Chapter Outline 11.1. Principles of Carbon Isotope Stratigraphy 221 11.2. Spatial Heterogeneity of d13C of Dissolved Inorganic STRATIGRAPHY p0015 The potential of marine carbonate d13 C values to date and correlate rocks relies

  10. Constraint of the CO2 rise by new atmospheric carbon isotopic measurements during the last deglaciation

    E-Print Network [OSTI]

    Chappellaz, Jrme

    Click Here for Full Article Constraint of the CO2 rise by new atmospheric carbon isotopic increase of atmospheric carbon dioxide (CO2) during the last glacialinterglacial climatic transition remain debated. We analyzed the parallel evolution of CO2 and its stable carbon isotopic ratio (d13 CO2

  11. Vegetation succession and carbon sequestration in a coastal wetland in northwest Florida: Evidence from carbon isotopes

    E-Print Network [OSTI]

    Vegetation succession and carbon sequestration in a coastal wetland in northwest Florida: Evidence from carbon isotopes Yonghoon Choi and Yang Wang Department of Geological Sciences, Florida State. Measurements of stable carbon isotopic ratios as well as carbon (C), nitrogen (N), and phosphorus (P) contents

  12. Examining the transport of ammonia emissions across landscapes using nitrogen isotope ratios

    E-Print Network [OSTI]

    Elliott, Emily M.

    fertilizer application, during periods of low or no fertilization, vehicle NH3 emissions can be a substantialExamining the transport of ammonia emissions across landscapes using nitrogen isotope ratios J 2014 Keywords: Ammonia Emissions Isotope Nitrogen Ammonium a b s t r a c t The proportion of reactive

  13. Contribution of restricted rotors to quantum sieving of hydrogen isotopes B. C. Hathorn,1

    E-Print Network [OSTI]

    Hathorn, Bryan C.

    , energy intensive, and expensive, and new methods of efficient isotope separation, which are cheap of isotopically substituted hydrogen molecules adsorbed into single-walled car- bon nanotubes are calculated using that the introduction of quantum zero-point energy in the translational coordinates of molecules enclosed in carbon

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

    E-Print Network [OSTI]

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

  15. Heavy metals and lead isotopes in sdB stars

    E-Print Network [OSTI]

    S. O'Toole; U. Heber

    2006-12-19

    We present a detailed abundance analysis of high-resolution ultraviolet echelle spectra of five subdwarf B stars obtained with HST-STIS The goal of our observations was to test the hypothesis that pulsations in sdBs are correlated to the surface abundances of iron-group elements. We study two pulsators and three non-pulsators and determined abundances for 25 elements including the iron group and even heavier elements such as tin and lead using LTE spectrum synthesis techniques. We find strong enrichments of heavy elements up to 2.9dex with respect to solar which are probably caused by atomic diffusion processes. No clear-cut correlation between pulsations and metal abundances becomes apparent. Abundances for lead isotopes are derived from very high resolution spectra using an UV line of triply ionised lead. As Pb terminates the s-process sequence Pb isotopic abundance ratios yield important constraints. It is very difficult to measure them in hot stars. For the first time we were able to measure them in two subluminous B stars and conclude that the 207Pb/208Pb is solar.

  16. Nucleosynthesis in Massive Stars - Including All Stable Isotopes

    E-Print Network [OSTI]

    A. Heger; R. D. Hoffman; T. Rauscher; S. E. Woosley

    2000-06-25

    We present the first calculations to follow the evolution of all stable isotopes (and their abundant radioactive progenitors) in a finely zoned stellar model computed from the onset of central hydrogen burning through explosion as a Type II supernova. The calculations were performed for a 15 solar mass Pop I star using the most recently available set of experimental and theoretical nuclear data, revised opacity tables, and taking into account mass loss due to stellar winds. We find the approximately solar production of proton-rich isotopes above a mass number of A=120 due to the gamma-process. We also find a weak s-process, which along with the gamma-process and explosive helium and carbon burning, produces nearly solar abundances of almost all nuclei from A=60 to 85. A few modifications of the abundances of heavy nuclei above mass 90 by the s-process are also noted and discussed. New weak rates lead to significant alteration of the properties of the presupernova core.

  17. 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.

  18. An efficient palladium isotope chromatograph (EPIC) for hydrogen

    SciTech Connect (OSTI)

    Rutherford, W.M.

    1989-06-20

    The efficient palladium isotope chromatography (EPIC) system is based on a palladium displacement chromatograph developed and tested for the preparative scale separation of the isotopes of hydrogen. Rapid cycling and high efficiency are obtained by use of high-performance packing operating at an elevated temperature (80/degree/C) and elevated pressure (1.5 atm). The process, which was tested with a 50/50 mixture of hydrogen and deuterium, depends on the exploitation of thermally driven pressure differences to recover and recycle the mixed transition zone between the bands of the pure components and also to recover and recycle the hydrogen gas used as the displacing agent. The purity of the product is significantly enhanced by partially backfilling the column with pure deuterium at the beginning of each displacement cycle. The computer-controlled system operates continuously, and it is capable of separating 2.2 std L/hr of feed at product assays of 99.86 at. % hydrogen and 99.992 at. % deuterium. 11 refs., 5 figs., 1 tab.

  19. Distribution of Hydrogen Isotopes, Carbon and Beryllium on In-Vessel Surfaces in the Various JET Divertors

    E-Print Network [OSTI]

    Distribution of Hydrogen Isotopes, Carbon and Beryllium on In-Vessel Surfaces in the Various JET Divertors

  20. Production of isotopes in 1.A GeV $^{208}Pb$ on proton reactions relevant for accelerator-driven systems

    E-Print Network [OSTI]

    Wlazlo, W; Armbruster, P; Benlliure, J; Bernas, M; Boudard, A; Czajkowski, S; Farget, F; Legrain, R; Leray, S; Mustapha, B; Pravikoff, M S; Schmidt, K H; Stphan, C; Taieb, J; Tassan-Got, L; Volant, C

    1999-01-01

    Production of isotopes in 1.A GeV $^{208}Pb$ on proton reactions relevant for accelerator-driven systems

  1. Forensic Applications of Light-Element Stable Isotope Ratios of Ricinus communis Seeds and Ricin Preparations

    SciTech Connect (OSTI)

    Kreuzer, Helen W.; West, Jason B.; Ehleringer, James

    2013-01-01

    Seeds of the castor plant Ricinus communis, also known as castor beans, are of forensic interest because they are the source of the poison ricin. We have tested whether stable isotope ratios of castor seeds and ricin prepared by various methods can be used as a forensic signature. We collected over 300 castor seed samples from locations around the world and measured the C, N, O, and H stable isotope ratios of the whole seeds, oil, and three types of ricin preparations. Our results demonstrate that N isotope ratios can be used to correlate ricin prepared by any of these methods to source seeds. Further, stable isotope ratios distinguished >99% of crude and purified ricin protein samples in pair-wise comparison tests. Stable isotope ratios therefore constitute a valuable forensic signature for ricin preparations.

  2. Collectivity evolution in the neutron-rich Pd isotopes towards the N=82 shell closure

    E-Print Network [OSTI]

    Wang, H; Takeuchi, S; Matsushita, M; Doornenbal, P; Motobayashi, T; Steppenbeck, D; Yoneda, K; Baba, H; Caceres, L; Dombradi, Zs; Kobayashi, K; Kondo, Y; Lee, J; Li, K; Liu, H; Minakata, R; Nishimura, D; Otsu, H; Sakaguchi, S; Sakurai, H; Scheit, H; Sohler, D; Sun, Y; Tian, Z; Tanaka, R; Togano, Y; Vajta, Zs; Yang, Z; Yamamoto, T; Ye, Y; Yokoyama, R

    2013-01-01

    The neutron-rich, even-even 122,124,126Pd isotopes has been studied via in-beam gamma-ray spectroscopy at the RIKEN Radioactive Isotope Beam Factory. Excited states at 499(9), 590(11), and 686(17) keV were found in the three isotopes, which we assign to the respective 2+ -> 0+ decays. In addition, a candidate for the 4+ state at 1164(20) keV was observed in 122Pd. The resulting Ex(2+) systematics are essentially similar to those of the Xe (Z=54) isotopic chain and theoretical prediction by IBM-2, suggesting no serious shell quenching in the Pd isotopes in the vicinity of N=82.

  3. 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.

  4. Isotope effect in tunnelling ionization of neutral hydrogen molecules

    E-Print Network [OSTI]

    Wang, X; Atia-Tul-Noor, A; Hu, B T; Kielpinski, D; Sang, R T; Litvinyuk, I V

    2015-01-01

    It has been recently predicted theoretically that due to nuclear motion light and heavy hydrogen molecules exposed to strong electric field should exhibit substantially different tunneling ionization rates (O.I. Tolstikhin, H.J. Worner and T. Morishita, Phys. Rev. A 87, 041401(R) (2013) [1]). We studied that isotope effect experimentally by measuring relative ionization yields for each species in a mixed H2/D2 gas jet interacting with intense femtosecond laser pulses. In a reaction microscope apparatus we detected ionic fragments from all contributing channels (single ionization, dissociation, and sequential double ionization) and determined the ratio of total single ionization yields for H2 and D2. The measured ratio agrees quantitatively with the prediction of the generalized weak-field asymptotic theory in an apparent failure of the frozen-nuclei approximation.

  5. 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.

  6. An EBIS system for rare isotope science project in Korea

    SciTech Connect (OSTI)

    Kim, Jongwon E-mail: jehan@ibs.re.kr E-mail: khyi@ibs.re.kr; Han, Jae-Eun E-mail: jehan@ibs.re.kr E-mail: khyi@ibs.re.kr; Son, Hyock-Jun E-mail: jehan@ibs.re.kr E-mail: khyi@ibs.re.kr; Yi, Kun-Hui E-mail: jehan@ibs.re.kr E-mail: khyi@ibs.re.kr; Zhao, Liangji E-mail: kim@far-tech.com; Kim, Jin-Soo E-mail: kim@far-tech.com

    2015-01-09

    An EBIS system has been designed to be used as a charge breeder for the post accelerator of an ISOL system. An electron gun, which is designed to produce a maximum current of 3 A at the beam energy of 20 kV, will be acquired from the Budker Institute, Novosibirsk. Electron beam optics calculations of the EBIS system as well as of the gun assembly have been performed using PBGUNS and TRAK. A superconducting solenoid with a maximum field of 6 T is to be used to compress the electron beam. A test stand, which includes the gun assembly and a high-power electron beam collector, is being designed and will be ready for the gun test in the end of this year. Charge breeding simulation using EBIS0D and CBSIM has been performed for a few key isotopes.

  7. Gamma Spectrum from Neutron Capture on Tungsten Isotopes

    SciTech Connect (OSTI)

    Hurst, Aaron; Summers, Neil; Sleaford, Brad; Firestone, Richard B; Belgya, T.; Revay, Z.S.

    2010-04-29

    An evaluation of thermal neutron capture on the stable tungsten isotopes is presented, with preliminary results for the compound systems 183;184;185;187W. The evaluation procedure compares the g-ray cross-section data collected at the Budapest reactor, with Monte Carlo simulations of g-ray emission following the thermal neutron-capture process. The statistical-decay code DICEBOX was used for the Monte Carlo simulations. The evaluation yields new gamma rays in 185W and the confirmation of spins in 187W, raising the number of levels below which the level schemes are considered complete, thus increasing the number of levels that can be used in neutron data libraries.

  8. Level densities and thermodynamical properties of Pt and Au isotopes

    E-Print Network [OSTI]

    F. Giacoppo; F. L. Bello Garrote; L. A. Bernstein; D. L. Bleuel; T. K. Eriksen; R. B. Firestone; A. Grgen; M. Guttormsen; T. W. Hagen; B. V. Kheswa; M. Klintefjord; P. E. Koehler; A. C. Larsen; H. T. Nyhus; T. Renstrm; E. Sahin; S. Siem; T. Tornyi

    2014-11-28

    The nuclear level densities of $^{194-196}$Pt and $^{197,198}$Au below the neutron separation energy have been measured using transfer and scattering reactions. All the level density distributions follow the constant-temperature description. Each group of isotopes is characterized by the same temperature above the energy threshold corresponding to the breaking of the first Cooper pair. A constant entropy excess $\\Delta S=1.9$ and $1.1$ $k_B$ is observed in $^{195}$Pt and $^{198}$Au with respect to $^{196}$Pt and $^{197}$Au, respectively, giving information on the available single-particle level space for the last unpaired valence neutron. The breaking of nucleon Cooper pairs is revealed by sequential peaks in the microcanonical caloric curve.

  9. 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.

  10. Performance and safety parameters for the high flux isotope reactor

    SciTech Connect (OSTI)

    Ilas, G. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States); Primm III, T. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States); Primm Consulting, LLC, 945 Laurel Hill Road, Knoxville, TN 37923 (United States)

    2012-07-01

    A Monte Carlo depletion model for the High Flux Isotope Reactor (HFIR) Cycle 400 and its use in calculating parameters of relevance to the reactor performance and safety during the reactor cycle are presented in this paper. This depletion model was developed to serve as a reference for the design of a low-enriched uranium (LEU) fuel for an ongoing study to convert HFIR from high-enriched uranium (HEU) to LEU fuel; both HEU and LEU depletion models use the same methodology and ENDF/B-VII nuclear data as discussed in this paper. The calculated HFIR Cycle 400 parameters, which are compared with measurement data from critical experiments performed at HFIR, data included in the HFIR Safety Analysis Report (SAR), or data reported by previous calculations, provide a basis for verification or updating of the corresponding SAR data. (authors)

  11. Performance and Safety Parameters for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Ilas, Germina [ORNL; Primm, Trent [Primm Consulting, LLC

    2012-01-01

    A Monte Carlo depletion model for the High Flux Isotope Reactor (HFIR) Cycle 400 and its use in calculating parameters of relevance to the reactor performance and safety during the reactor cycle are presented in this paper. This depletion model was developed to serve as a reference for the design of a low-enriched uranium (LEU) fuel for an ongoing study to convert HFIR from high-enriched uranium (HEU) to LEU fuel; both HEU and LEU depletion models use the same methodology and ENDV/B-VII nuclear data as discussed in this paper. The calculated HFIR Cycle 400 parameters, which are compared when available with measurement data from critical experiments performed at HFIR, data included in the HFIR Safety Analysis Report (SAR), or data reported by previous calculations, provide a basis for verification or updating of the corresponding SAR data.

  12. Methods for separating medical isotopes using ionic liquids

    DOE Patents [OSTI]

    Luo, Huimin; Boll, Rose Ann; Bell, Jason Richard; Dai, Sheng

    2014-10-21

    A method for extracting a radioisotope from an aqueous solution, the method comprising: a) intimately mixing a non-chelating ionic liquid with the aqueous solution to transfer at least a portion of said radioisotope to said non-chelating ionic liquid; and b) separating the non-chelating ionic liquid from the aqueous solution. In preferred embodiments, the method achieves an extraction efficiency of at least 80%, or a separation factor of at least 1.times.10.sup.4 when more than one radioisotope is included in the aqueous solution. In particular embodiments, the method is applied to the separation of medical isotopes pairs, such as Th from Ac (Th-229/Ac-225, Ac-227/Th-227), or Ra from Ac (Ac-225 and Ra-225, Ac-227 and Ra-223), or Ra from Th (Th-227 and Ra-223, Th-229 and Ra-225).

  13. Exotic fission properties of highly neutron-rich Uranium isotopes

    E-Print Network [OSTI]

    L. Satpathy; S. K. Patra; R. K. Choudhury

    2007-03-05

    The series of Uranium isotopes with $N=154 \\sim 172$ around the magic number N=162/164 are identified to be thermally fissile. The thermal neutron fission of a typical representative $^{249}$U of this region amenable to synthesis in the radioactive ion beam facilities is considered here. Semiempirical study of fission barrier height and width shows this nucleus to be infinitely stable against spontaneous fission due to increase in barrier width arising out of excess neutrons. Calculation of probability of fragment mass yields and microscopic study in relativistic mean field theory, show this nucleus to undergo a new mode of thermal fission decay termed {\\it multifragmentation fission} where a number of prompt scission neutrons are simultaneously released along with the two heavy fission fragments.

  14. Particle-particle random phase approximation applied to Beryllium isotopes

    E-Print Network [OSTI]

    Guillaume Blanchon; Nicole Vinh Mau; Angela Bonaccorso; Marc Dupuis; Nathalie Pillet

    2010-07-16

    This work is dedicated to the study of even-even 8-14 Be isotopes using the particle-particle Random Phase Approximation that accounts for two-body correlations in the core nucleus. A better description of energies and two-particle amplitudes is obtained in comparison with models assuming a neutron closed-shell (or subshell) core. A Wood-Saxon potential corrected by a phenomenological particle-vibration coupling term has been used for the neutron-core interaction and the D1S Gogny force for the neutron-neutron interaction. Calculated ground state properties as well as excited state ones are discussed and compared to experimental data. In particular, results suggest the same 2s_1/2-1p_1/2 shell inversion in 13Be as in 11Be.

  15. Ion extraction and charge exchange in laser isotope separation

    SciTech Connect (OSTI)

    Hostein, D.; Doneddu, F.

    1996-02-01

    In the atomic vapor laser isotope separation (AVLIS) process, a vapor is ionized by pulsed laser beams, and the ions are extracted by negatively biased collectors. The authors compute the unsteady dynamics of the photoplasma using a two-dimensional (2-D) particle-in-cell (PIC) code. Collisions between ions and neutral species are simulated by a Monte Carlo technique. The plasma dynamics is visualized by snapshots of particle positions showing the directions of their velocities. The three kinds of particles (electrons, photo-ions, and ions created by charge exchange) are marked by different colors. The graphic outputs illustrate the motion of the electrons toward the anodes, the vertical drift of the plasma, its erosion by the transient ion sheath, and nonselective ionization by charge exchange.

  16. CRYOGENIC ADSORPTION OF HYDROGEN ISOTOPES OVER NANO-STRUCTURED MATERIALS

    SciTech Connect (OSTI)

    Xiao, S.; Heung, L.

    2010-10-07

    Porous materials such as zeolites, activated carbon, silica gels, alumina and a number of industrial catalysts are compared and ranked for hydrogen and deuterium adsorption at liquid nitrogen temperature. All samples show higher D{sub 2} adsorption than that of H{sub 2}, in which a HY sample has the greatest isotopic effect while 13X has the highest hydrogen uptake capacity. Material's moisture content has significant impact to its hydrogen uptake. A material without adequate drying could result in complete loss of its adsorption capacity. Even though some materials present higher H{sub 2} adsorption capacity at full pressure, their adsorption at low vapor pressure may not be as good as others. Adsorption capacity in a dynamic system is much less than in a static system. A sharp desorption is also expected in case of temperature upset.

  17. NEST-GENERATION TCAP HYDROGEN ISOTOPE SEPARATION PROCESS

    SciTech Connect (OSTI)

    Heung, L; Henry Sessions, H; Anita Poore, A; William Jacobs, W; Christopher Williams, C

    2007-08-07

    A thermal cycling absorption process (TCAP) for hydrogen isotope separation has been in operation at Savannah River Site since 1994. The process uses a hot/cold nitrogen system to cycle the temperature of the separation column. The hot/cold nitrogen system requires the use of large compressors, heat exchanges, valves and piping that is bulky and maintenance intensive. A new compact thermal cycling (CTC) design has recently been developed. This new design uses liquid nitrogen tubes and electric heaters to heat and cool the column directly so that the bulky hot/cold nitrogen system can be eliminated. This CTC design is simple and is easy to implement, and will be the next generation TCAP system at SRS. A twelve-meter column has been fabricated and installed in the laboratory to demonstrate its performance. The design of the system and its test results to date is discussed.

  18. 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.

  19. 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.

  20. Beta-decay measurements of neutron-deficient cesium isotopes

    SciTech Connect (OSTI)

    Parry, R.F.

    1983-03-01

    Beta decay endpoint energy measurements of the neutron deficient cesium isotopes were done using an energy spectrum shape fitting technique. This was a departure from the typical method of endpoint energy analysis, the Fermi-Kurie plot. A discussion of the shape fitting procedure and its improved features are discussed. These beta endpoint measurements have led to total decay energies (Q/sub EC/) of the neutron deficient /sup 119/ /sup 123/Cs isotopes. The total decay energies of /sup 122m/Cs (Q/sub EC/ = 6.95 +- 0.25 MeV) and /sup 119/Cs (Q/sub EC/ = 6.26 +- 0.29 MeV) were new measurements. The total decay energies of /sup 123/Cs (Q/sub EC/ = 4.05 +- 0.18 MeV), /sup 122g/Cs (Q/sub EC/ = 7.05 +- 0.18 MeV), /sup 121/Cs (Q/sub EC/ = 5.21 +- 0.22 MeV), and /sup 120/Cs (Q/sub EC/ = 7.38 +- 0.23 MeV) were measurements with significantly improved uncertainties as compared to the literature. Further, a combination of the energy levels derived from previous literature gamma-gamma coincident measurements and the experimental beta-coincident gamma decay energies has supported an improved level scheme for /sup 121/Xe and the proposal of three new energy levels in /sup 119/Xe. Comparison of the experimental cesium mass excesses (determined with our Q/sub EC/ values and known xenon mass excesses) with both the literature and theoretical predicted values showed general agreement except for /sup 120/Cs. Possible explanations for this deviation are discussed.

  1. Consistent Data Assimilation of Isotopes: 242Pu and 105Pd

    SciTech Connect (OSTI)

    G. Palmiotti; H. Hiruta; M. Salvatores

    2012-09-01

    In this annual report we illustrate the methodology of the consistent data assimilation that allows to use the information coming from integral experiments for improving the basic nuclear parameters used in cross section evaluation. A series of integral experiments are analyzed using the EMPIRE evaluated files for 242Pu and 105Pd. In particular irradiation experiments (PROFIL-1 and -2, TRAPU-1, -2 and -3) provide information about capture cross sections, and a critical configuration, COSMO, where fission spectral indexes were measured, provides information about fission cross section. The observed discrepancies between calculated and experimental results are used in conjunction with the computed sensitivity coefficients and covariance matrix for nuclear parameters in a consistent data assimilation. The results obtained by the consistent data assimilation indicate that not so large modifications on some key identified nuclear parameters allow to obtain reasonable C/E. However, for some parameters such variations are outside the range of 1 s of their initial standard deviation. This can indicate a possible conflict between differential measurements (used to calculate the initial standard deviations) and the integral measurements used in the statistical data adjustment. Moreover, an inconsistency between the C/E of two sets of irradiation experiments (PROFIL and TRAPU) is observed for 242Pu. This is the end of this project funded by the Nuclear Physics Program of the DOE Office of Science. We can indicate that a proof of principle has been demonstrated for a few isotopes for this innovative methodology. However, we are still far from having explored all the possibilities and made this methodology to be considered proved and robust. In particular many issues are worth further investigation: Non-linear effects Flexibility of nuclear parameters in describing cross sections Multi-isotope consistent assimilation Consistency between differential and integral experiments

  2. 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.

  3. Low-energy electric dipole response of Sn isotopes

    E-Print Network [OSTI]

    P. Papakonstantinou; H. Hergert; V. Yu. Ponomarev; R. Roth

    2014-03-10

    We study the low-energy dipole (LED) strength distribution along the Sn isotopic chain in both the isoscalar (IS) and the isovector (IV, or E1) electric channels, to provide testable predictions and guidance for new experiments with stable targets and radioactive beams. We use the self-consistent Quasi-particle Random-Phase Approximation (QRPA) with finite-range interactions and mainly the Gogny D1S force. We analyze also the performance of a realistic two-body interaction supplemented by a phenomenological three-body contact term. We find that from N=50 and up to the N=82 shell closure (132Sn) the lowest-energy part of the IS-LED spectrum is dominated by a collective transition whose properties vary smoothly with neutron number and which cannot be interpreted as a neutron-skin oscillation. For the neutron-rich species this state contributes to the E1 strength below particle threshold, but much more E1 strength is carried by other, weak but numerous transitions around or above threshold. We find that strong structural changes in the spectrum take effect beyond N=82, namely increased LED strength and lower excitation energies. Our results with the Gogny interaction are compatible with existing data. On this basis we predict that a) the summed IS strength below particle threshold shall be of the same order of magnitude for N=50-82, b) the summed E1 strength up to approximately 12 MeV shall be similar for N=50-82 MeV, while c) the summed E1 strength below threshold shall be of the same order of magnitude for N ~ 64 - 82 and much weaker for the lighter, more-symmetric isotopes. We point out a general agreement of our results with other non-relativistic studies, the absence of a collective IS mode in some of those studies, and a possibly radical disagreement with relativistic models.

  4. Innovative lasers for uranium isotope separation. [Progress report

    SciTech Connect (OSTI)

    Brake, M.L.; Gilgenbach, R.M.

    1991-06-01

    Copper vapor lasers have important applications to uranium atomic vapor laser isotope separation (AVLIS). The authors have spent the first two years of their project investigating two innovative methods of exciting/pumping copper vapor lasers which have the potential to improve the efficiency and scaling of large laser systems used in uranium isotope separation. Experimental research has focused on the laser discharge kinetics of (1) microwave, and (2) electron beam excitation/pumping of large-volume copper vapor lasers. During the first year, the experiments have been designed and constructed and initial data has been taken. During the second year these experiments have been diagnosed. Highlights of some of the second year results as well as plans for the future include the following: Microwave resonant cavity produced copper vapor plasmas at 2.45 GHz, have been investigated. A CW (0--500 W) signal heats and vaporizes the copper chloride to provide the atomic copper vapor. A pulsed (5 kW, 0.5--5kHz) signal is added to the incoming CW signal via a hybrid mixer to excite the copper states to the laser levels. An enhancement of the visible radiation has been observed during the pulsed pardon of the signal. Electrical probe measurements have been implemented on the system to verify the results of the electromagnetic model formulated last year. Laser gain measurements have been initiated with the use of a commercial copper vapor laser. Measurements of the spatial profile of the emission are also currently being made. The authors plan to increase the amount of pulsed microwave power to the system by implementing a high power magnetron. A laser cavity will be designed and added to this system.

  5. Big Bang Nucleosynthesis and the Helium Isotope Ratio

    E-Print Network [OSTI]

    Ryan Cooke

    2015-10-09

    The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of this quantity tentatively support new physics beyond the standard model but, historically, this method has suffered from hidden systematic uncertainties. In this letter, I show that a combined measurement of the primordial deuterium abundance and the primordial helium isotope ratio has the potential to provide a complementary and reliable probe of new physics beyond the standard model. Using the recent determination of the primordial deuterium abundance and assuming that the measured pre-solar 3He/4He meteoritic abundance reflects the primordial value, a bound can be placed on the effective number of neutrino species, Neff(BBN) = 3.01 (+0.95 -0.76, with 95 per cent confidence). Although this value of Neff supports the standard model, it is presently unclear if the pre-solar 3He/4He ratio reflects the primordial value. New astrophysical measurements of the helium isotope ratio in near-pristine environments, together with updated calculations and experimental values of several important nuclear reactions (some of which are already being attempted), will lead to much improved limits on possible departures from the standard model. To this end, I describe an analysis strategy to measure the 3He I flux emitted from nearby low metallicity H II regions. The proposed technique can be attempted with the next generation of large telescopes, and will be easier to realize in metal-poor H II regions with quiescent kinematics.

  6. Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring

    SciTech Connect (OSTI)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia) [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Korsch, Michael [CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia)] [CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Winchester, Wayne; Devenish, Matthew; Hobbs, Thad [Esperance Cleanup and Recovery Project, Western Australia (WA) Department of Transport, Esperance 6450 (Australia)] [Esperance Cleanup and Recovery Project, Western Australia (WA) Department of Transport, Esperance 6450 (Australia); Main, Cleve; Smith, Gerard [Animal Health Laboratory, Department of Agriculture and Food, Perth 6151, WA (Australia)] [Animal Health Laboratory, Department of Agriculture and Food, Perth 6151, WA (Australia); Rosman, Kevin; Howearth, Lynette; Burn-Nunes, Laurie [Curtin University, Department of Imaging and Applied Physics, Bentley 6102, WA (Australia)] [Curtin University, Department of Imaging and Applied Physics, Bentley 6102, WA (Australia); Seow, Jimmy; Oxford, Cameron [Department of Environment and Conservation, Booragoon 6154, WA (Australia)] [Department of Environment and Conservation, Booragoon 6154, WA (Australia); Yun, Gracie; Gillam, Lindsay [Department of Health, East Perth 6004, WA (Australia)] [Department of Health, East Perth 6004, WA (Australia); Crisp, Michelle [LED (Locals for Esperance Development), Esperance 6450, WA (Australia)] [LED (Locals for Esperance Development), Esperance 6450, WA (Australia)

    2012-01-15

    In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. - Highlights: Black-Right-Pointing-Triangle Lead carbonate concentrate. Black-Right-Pointing-Triangle Successful use of Pb isotopes in identifying sources of Pb arising from transport and shipping. Black-Right-Pointing-Triangle Use of Pb isotopes in legal proceedings and their use in cleanup of residences. Black-Right-Pointing-Triangle Use of Pb isotopes in cleanup of a residual 9000 tonnes of Pb carbonate and in ongoing monitoring.

  7. Literature review of United States utilities computer codes for calculating actinide isotope content in irradiated fuel

    SciTech Connect (OSTI)

    Horak, W.C.; Lu, Ming-Shih.

    1991-12-01

    This paper reviews the accuracy and precision of methods used by United States electric utilities to determine the actinide isotopic and element content of irradiated fuel. After an extensive literature search, three key code suites were selected for review. Two suites of computer codes, CASMO and ARMP, are used for reactor physics calculations; the ORIGEN code is used for spent fuel calculations. They are also the most widely used codes in the nuclear industry throughout the world. Although none of these codes calculate actinide isotopics as their primary variables intended for safeguards applications, accurate calculation of actinide isotopic content is necessary to fulfill their function.

  8. Isotope and Nuclear Chemistry Division annual report FY 1986, October 1985-September 1986

    SciTech Connect (OSTI)

    Heiken, J.H. (ed.)

    1987-06-01

    This report describes progress in the major research and development programs carried out in FY 1986 by the Isotope and Nuclear Chemistry Division. The report includes articles on radiochemical diagnostics and weapons tests; weapons radiochemical diagnostics research and development; other unclassified weapons research; stable and radioactive isotope production and separation; chemical biology and nuclear medicine; element and isotope transport and fixation; actinide and transition metal chemistry; structural chemistry, spectroscopy, and applications; nuclear structure and reactions; irradiation facilities; advanced concepts and technology; and atmospheric chemistry.

  9. 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 isotopes 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.

  10. Stable isotope variations in Late Pennsylvanian brachiopods from cyclic sedimentary deposits: paleoenvironmental and diagenetic implications

    E-Print Network [OSTI]

    Adlis, David Scott

    1986-01-01

    of carbon and oxygen were determined on well preserved shells of the brachiopod r ri h ' I n nv from the Necessity and Colony Creek Shales on the Eastern Shelf of the Midland Basin in order to relate isotopic shifts to transgression and regression... of ~lggg~nv x 42 Colony Creek Brad section scatter plot of carbon vs. oxygen isotope values of the prismatic and fibrous shell layers of ~lgn~gy0tta 43 10 Colony Creek North section scatter plot of carbon vs. oxygen isotope values of the prismatic...

  11. Full $fp$-shell study of even-even $^{48-56}$Ti isotopes

    E-Print Network [OSTI]

    F. A. Majeed; A. A. Auda

    2006-02-02

    The level schemes and transition rates {\\em B}({\\em E}2;$\\uparrow$) of eve-even $^{48-56}$Ti isotopes were studied by performing large-scale shell model calculations with FPD6 and GXPF1 effective interactions. Excellent agreement were obtained by comparing the first 2$^{+}$ level for all isotopes with the recently available experimental data, but studying the transition strengths {\\em B}({\\em E}2; 0$^+_{g.s.} \\to2^+_1$) for all Ti isotopes using constant proton-neutron effective charges prove the limitations of the present large-scale calculations to reproduce the experiment in detail.

  12. Standard test method for uranium and plutonium concentrations and isotopic abundances by thermal ionization mass spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the determination of the concentration and isotopic composition of uranium and plutonium in solutions. The purified uranium or plutonium from samples ranging from nuclear materials to environmental or bioassay matrices is loaded onto a mass spectrometric filament. The isotopic ratio is determined by thermal ionization mass spectrometry, the concentration is determined by isotope dilution. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish safety and health practices and determine the applicability of regulatory limitations prior to use.

  13. Integrated safeguards and security for the INEL Special Isotope Separation Plant

    SciTech Connect (OSTI)

    Warner, G.F.; Zack, N.R.

    1990-06-12

    This paper describes the approach that was taken in developing safeguards and security design criteria to be used for the Special Isotope Separation (SIS) Production Plant. The US Department of Energy has postponed the construction of the SIS Production Plant that was to be built at the Idaho National Engineering Laboratory (INEL) site located near Idaho Falls, Idaho. The SIS Plant planned to isotopically enrich plutonium utilizing the Atomic Vapor Laser Isotope Separation (AVLIS) process developed at the Lawrence Livermore National Laboratory. Westinghouse Idaho Nuclear Co., Inc. as a prime contractor to the DOE Idaho Operations Office, was to operate the Plant.

  14. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis

    SciTech Connect (OSTI)

    Lugmair, G.W. ); Galer, S.J.G. Max-Planck-Inst. fuer Chemie, Mainz )

    1992-04-01

    Results of a wide-ranging isotopic investigation of the unique Antarctican angrite LEW-86010 (LEW) are presented, together with a reassessment of the type angrite Angra dos Reis (ADOR). The principal objectives of this study are to obtain precise radiometric ages, initial Sr isotopic compositions, and to search for the erstwhile presence of the short-lived nuclei {sup 146}Sm and {sup 26}Al via their daughter products. The isotopic compositions of Sm, U, Ca, and Ti were also measured. This allows a detailed appraisal to be made of the relations between, and the genealogy of, these two angrites.

  15. Using bioenergetics and stable isotopes to assess the trophic role of rusty crayfish

    E-Print Network [OSTI]

    Vander Zanden, Jake

    Using bioenergetics and stable isotopes to assess the trophic role of rusty crayfish (Orconectes and implications of their foraging behavior on littoral ecosystems. We created a bioenergetics model for rusty

  16. Quantifying Peptides in Isotopically Labeled Protease Digests by Ion Mobility/Time-of-Flight

    E-Print Network [OSTI]

    Clemmer, David E.

    Quantifying Peptides in Isotopically Labeled Protease Digests by Ion Mobility/Time-of-Flight Mass-terminus can be accomplished by digesting proteins in 18O-labeled water,11-20 resulting in incorpora- tion

  17. Comprehensive analysis of metabolic pathways through the combined use of multiple isotopic tracers

    E-Print Network [OSTI]

    Antoniewicz, Maciek Robert

    2006-01-01

    Metabolic Flux Analysis (MFA) has emerged as a tool of great significance for metabolic engineering and the analysis of human metabolic diseases. An important limitation of MFA, as carried out via stable isotope labeling ...

  18. 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.

  19. Isotopic and microbial indicators of sewage pollution from Stone Town, Zanzibar, Tanzania

    E-Print Network [OSTI]

    Harvell, Catherine Drew

    Isotopic and microbial indicators of sewage pollution from Stone Town, Zanzibar, Tanzania Molly A, Washington, DC, USA c Institute of Marine Sciences, University of Dar es Salaam, Zanzibar, Tanzania a r t i c

  20. Fe isotope and trace element geochemistry of the Neoproterozoic syn-glacial Rapitan iron formation

    E-Print Network [OSTI]

    Long, Bernard

    pattern likely records a steep isotopic gradient across the iron chemocline in Rapitan seawater. 2011 metabolism, and function as a micronu- trient (Anbar, 2004; Beard et al., 2003a; Johnson et al., 2008a). Iron

  1. Characterization of marine exopolymeric substance (EPS) responsible for binding of thorium (IV) isotopes

    E-Print Network [OSTI]

    Alvarado Quiroz, Nicolas Gabriel

    2005-08-29

    The functional group composition of acid polysaccharides was determined after isolation using cross-flow ultrafiltration, radiolabeling with 234Th(IV) and other isotopes, and separation using isoelectric focusing (IEF) and ...

  2. A Hydrogen Isotope of Mass 2 Before the publication of this definitive paper on the

    E-Print Network [OSTI]

    . They probably estimated the chemical differences among isotopes to be small, perhaps too small to be measured, spectrographic evidence for the lines of 2 H obtained from samples of commercial tank hydro- gen. These lines

  3. An algorithm for U-Pb isotope dilution data reduction and uncertainty propagation

    E-Print Network [OSTI]

    McLean, Noah M.; Bowring, J.F.; Bowring, S.A.

    2011-06-01

    High-precision U-Pb geochronology by isotope dilution-thermal ionization mass spectrometry is integral to a variety of Earth science disciplines, but its ultimate resolving power is quantified by the uncertainties of calculated U-Pb dates...

  4. Holocene Paleohydrology and Paleoclimate at Treeline, North-Central Russia, Inferred from Oxygen Isotope

    E-Print Network [OSTI]

    Edwards, Thomas W.D.

    18 O from secondary evap- orative isotopic enrichment is aided by knowledge of the distribu- tion by glacial sea-level drawdown may have suppressed maritime climatic influence in what are now coastal areas

  5. Understanding denitrification with stable isotope measurements of N2: proof of concept study

    E-Print Network [OSTI]

    Downer, Roswell Curtis

    2004-01-01

    The biologically mediated removal of nitrogen from estuarine and shallow coastal waters was investigated using a new method for the determination of N? isotope ratios. This method employs the use of a chromatographic separation technique to purify...

  6. Application of kinetic isotope effects and theoretical calculations to interesting reaction mechanisms

    E-Print Network [OSTI]

    Hirschi, Jennifer Sue

    2009-05-15

    A variety of biological and organic reaction mechanisms are studied using powerful tools from experimental and theoretical chemistry. These tools include the precise measurement of kinetic isotope effects (KIEs) and the ...

  7. Clumped Isotope Thermometry in Deeply Buried Sedimentary Carbonates: The Effects of Bond Reordering Kinetics and Recrystallization

    E-Print Network [OSTI]

    Shenton, Brock Jay

    2014-08-06

    I utilize clumped isotope thermometry to explore the diagenetic and thermal histories of exhumed brachiopods, crinoids, cements, and host rock in the Palmarito Formation, Venezuela and the Bird Spring Formation, Nevada, USA. Carbonate components...

  8. 30TH INTERNATIONAL COSMIC RAY CONFERENCE Isotopic composition of cosmic-ray sources

    E-Print Network [OSTI]

    Moskalenko, Igor V.

    solar composition. Introduction CR source abundances are normally derived using the leaky Autnoma de Mxico, Mexico City, Mexico, 2008 Vol. 2 (OG part 1), pages 129132 ID 738 129 #12;ISOTOPIC

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

    E-Print Network [OSTI]

    Alexander, Becky

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

  10. ISOTOPIC COMPOSITION OF LIGHT NUCLEI IN COSMIC RAYS: RESULTS FROM AMS-01

    E-Print Network [OSTI]

    Becker, R.

    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper, we ...

  11. Towards an understanding of the carbon isotopic changes across the Toarcian oceanic anoxic event

    E-Print Network [OSTI]

    Cohen, Alison Margaret

    2005-01-01

    A combination of bulk carbon, biomarker and compound specific isotopic analyses were used in order to investigate the changes which accompanied the deposition of black shales during the upper tenuicostatum and lower ...

  12. Constraining diamond metasomatic growth using C-and N-stable isotopes: examples from Namibia

    E-Print Network [OSTI]

    Cartigny, Pierre

    Abstract The present paper provides C- and N-stable isotope characteristics, N-contents and N-aggregation; Metasomatism 1. Introduction Increasing evidence suggests that some eclogite nodules are recycled oceanic crust

  13. Leading chiral three-nucleon forces along isotope chains in the calcium region

    E-Print Network [OSTI]

    V. Som; A. Cipollone; C. Barbieri; P. Navrtil; T. Duguet

    2013-12-07

    Three-nucleon forces (3NFs), and in particular terms of the Fujita-Miyazawa type, strongly influence the structure of neutron-rich exotic isotopes. Ab-initio calculations have shown that chiral two- and three-nucleon interactions correctly reproduce binding energy systematics and neutron driplines of oxygen and nearby isotopes. Exploiting the novel self-consistent Gorkov-Green's function approach, we present the first investigation of Ar, K, Ca, Sc and Ti isotopic chains. Leading chiral 3N interactions are mandatory to reproduce the trend of binding energies throughout these chains and to obtain a good description of two-neutron separation energies. At the same time, nuclei in this mass region are systematically overbound by about 40 MeV and the $N=20$ magic gap is significantly overestimated. We conclude that ab-initio many-body calculations of mid-mass isotopic chains challenge modern theories of elementary nuclear interactions.

  14. Isoscalar and neutron modes in the E 1 spectra of Ni isotopes...

    Office of Scientific and Technical Information (OSTI)

    Isoscalar and neutron modes in the E 1 spectra of Ni isotopes and the relevance of shell effects and the continuum Citation Details In-Document Search This content will become...

  15. Variable carbon isotope fractionation expressed by aerobic CH4-oxidizing bacteria

    E-Print Network [OSTI]

    Chu, Kung-Hui "Bella"

    in biomass carbon isotopes is primarily due to differences in the fraction- ation effect at the formaldehyde in the production and consumption of CH4 oc- cur (e.g., Bergamaschi, 1997; Conrad et al., 1999; Avery and Martens

  16. U235: A Gamma Ray Analysis Code for Uranium Isotopic Determination

    Office of Scientific and Technical Information (OSTI)

    5727 U235: A Gamma Ray Analysis Code for Uranium Isotopic Determination DeLynn Clark December 1996 may not be those of the Laboratory. Work performed under the auspices of the U S...

  17. Lithium-Beryllium-Boron Isotopic Compositions in Meteoritic Hibonite: Implications for Origin of 10

    E-Print Network [OSTI]

    Nittler, Larry R.

    Lithium-Beryllium-Boron Isotopic Compositions in Meteoritic Hibonite: Implications for Origin of 10. 2003; Marhas & Goswami 2003). Beryllium-10 and 7 Be are primarily produced through the same

  18. Unusual Intramolecular Kinetic Isotope Effects: Selectivity beyond Transition State Theorys 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 ...

  19. Tracing Paleoclimate over the Past 25,000 Years Using Evidence from Radiogenic Isotopes

    E-Print Network [OSTI]

    Xie, Ruifang

    2013-04-30

    investigated the dynamics of the Intertropical Convergence Zone (ITCZ) over the past 25 kyr in the eastern equatorial Pacific by fingerprinting dust provenance using radiogenic isotopes (Nd, Sr, Pb) and trace elements (Fe, Si, Ba) in the detrital fraction...

  20. Facility for Rare Isotope Beams: The Journey Has Begun on DOE...

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

    Instead, they're created in extreme conditions such as the centers of exploding supernovae. These isotopes decay into the elements that we're more familiar with and by...

  1. Understanding H isotope adsorption and absorption of Al-alloys using modeling and experiments (LDRD: #165724)

    SciTech Connect (OSTI)

    Ward, Donald K.; Zhou, Xiaowang; Karnesky, Richard A.; Kolasinski, Robert; Foster, Michael E.; Thurmer, Konrad; Chao, Paul; Epperly, Ethan Nicholas; Zimmerman, Jonathan A.; Wong, Bryan M.; Sills, Ryan B.

    2015-09-01

    Current austenitic stainless steel storage reservoirs for hydrogen isotopes (e.g. deuterium and tritium) have performance and operational life-limiting interactions (e.g. embrittlement) with H-isotopes. Aluminum alloys (e.g.AA2219), alternatively, have very low H-isotope solubilities, suggesting high resistance towards aging vulnerabilities. This report summarizes the work performed during the life of the Lab Directed Research and Development in the Nuclear Weapons investment area (165724), and provides invaluable modeling and experimental insights into the interactions of H isotopes with surfaces and bulk AlCu-alloys. The modeling work establishes and builds a multi-scale framework which includes: a density functional theory informed bond-order potential for classical molecular dynamics (MD), and subsequent use of MD simulations to inform defect level dislocation dynamics models. Furthermore, low energy ion scattering and thermal desorption spectroscopy experiments are performed to validate these models and add greater physical understanding to them.

  2. Isotopic mass-dependence of noble gas diffusion coefficients in water

    E-Print Network [OSTI]

    Bourg, I.C.; Sposito, G.

    2008-01-01

    of nonpolar solutes in water: Computer simulations using theof ionic species in liquid water. Geochim. Cosmochim. Acta,noble gas isotope data. Water Resour. Res. 34, 2467-2483.

  3. 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. Fogare a mixture of fog and rain water. Dry season fog water is

  4. A stable isotope stratigraphy for the Axel Heiberg Fossil Forest and its application to Eocene climate

    E-Print Network [OSTI]

    Byrne, Monica C. (Monica Catherine)

    2005-01-01

    The Eocene era was a warm, climatically dynamic transitional period between the Paleocene greenhouse world and the Oligocene icehouse world. This study details carbon and hydrogen isotopic and biomarker analyses of samples ...

  5. Principal physical problems in laser separation of weighable amounts of a rare ytterbium isotope

    SciTech Connect (OSTI)

    Yakovlenko, Sergei I

    1998-11-30

    A review is provided of the work on laser separation of Yb isotopes, carried out at the Institute of General Physics of the Russian Academy of Sciences and at the 'Lad' Scientific - Production Enterprise during the last 4 - 5 years. The processes of Yb isotope separation by the AVLIS (atomic vapour laser isotope separation) method were investigated both theoretically (by computer simulation) and experimentally. The main topics considered in the review are the ionisation selectivity, the formation of laser beams and of vapour flow in the cavity, and the extraction of ions from a plasma. A facility for producing highly enriched {sup 168}Yb on an industrial scale is described. The rate of production of the enriched ytterbium is now 5 - 10 mg h{sup -1} (over 1 g per month). Commercially viable production of the enriched {sup 168}Yb isotope by the AVLIS method was achieved for the first time anywhere in the world. (review)

  6. Mass-independent sulfur isotope fractionation during photochemistry of sulfur dioxide

    E-Print Network [OSTI]

    Whitehill, Andrew (Andrew Richard)

    2015-01-01

    Mass-independent sulfur isotope signatures are observed in Archean and early Paleoproterozoic sedimentary sulfate and sulfide minerals, and provide the most robust constraints on early atmospheric oxygen levels. Smaller ...

  7. Report of Survey of Oak Ridge Isotope Enrichment (Calutron) Facility Building 9204-3

    Broader source: Energy.gov [DOE]

    The purpose of this document is to report the results of a survey conducted at the Isotope Enrichment Facility (IEF, Calutron, Building 9204-3) on the Y-12 Plant property at the Oak Ridge Site. The...

  8. Accepted Manuscript Title: Elemental and isotopic characterization of cane and beet

    E-Print Network [OSTI]

    Ehleringer, Jim

    , G. van der Peijl, S. Berends-Montero, J. Ehleringer, V. Zdanowicz PII: S0889-1575(10)00225-5 DOI., Berends- Montero, S., Ehleringer, J., & Zdanowicz, V., Elemental and isotopic characterization of cane

  9. Nuclear Science and Physics Data from the Isotopes Project, Lawrence Berkeley National Laboratory (LBNL)

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

    The Isotopes Project pages at Lawrence Berkeley National Laboratory have been a source of nuclear data and reference information since the mid-nineties. Almost all of the data, the results of analyses, the specialized charts and interfaces, and the extensive bibiographic references are fed to the National Nuclear Data Center (NNDC) at Brookhaven National Laboratory and maintained there. The Isotope Project pages at LBNL provide a glimpse of early versions for many of the nuclear data resources.

  10. Laser isotope separation: Uranium. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect (OSTI)

    1995-12-01

    The bibliography contains citations concerning the technology and assessment of laser separation of uranium isotopes, compounds, oxides, and alloys. Topics include uranium enrichment plants, isotope enriched materials, gaseous diffusion, centrifuge enrichment, reliability and safety, and atomic vapor separation. Citations also discuss commercial enrichment, market trends, licensing, international competition, and waste management. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  11. 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.

  12. Sustainability of gamma-ray isotopics evaluation codes

    SciTech Connect (OSTI)

    Vo, Duc [Los Alamos National Laboratory; Koskelo, Markku [AQUILA TECHNOLOGIES; Mcginnis, Brent [ORNL; Wang, Tzu - Feng [LLNL; Peerani, Paolo [IPSC, ISPRA, ITALY; Renha, Geraldo [ABACC, BRAZIL; Dias, Fabio C [NECB, BRAZIL

    2010-01-01

    In November 2005, the international workshop 'Gamma Evaluation Codes for Plutonium and Uranium Isotope Abundance Measurements by High-Resolution Gamma Spectrometry: Current Status and Future Challenges' was held in Karlsruhe, Germany. Some of the main issues discussed during the November 2005 meeting were related to concerns voiced by international inspectorate authorities such as the International Atomic Energy Agency (IAEA), the European Atomic Energy Community (EURATOM), and the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) about the standardization and sustainability of gamma-ray isotopic analysis codes that are commonly used during safeguards inspections. A follow-up international workshop was conducted in Oak Ridge, TN in 2008. This workshop was in response to needs expressed by the international safeguards community during the Karlsruhe meeting and recommendations made under Action Sheet 14; a cooperative effort between the U. S. Department of Energy and ABACC. The purpose of the Oak Ridge workshop was to bring code developers and end users together to better understand the capabilities and limitations of the codes; to discuss mechanisms to ensure these codes are sustained and quality tested; and to ensure updates or revisions are performed in a controlled manner. During an Action Sheet 14 meeting held in Rio de Janeiro, Brazil in which the IAEA and EURATOM participated as observers, and in subsequent meetings of the European Safeguards Research and Development Association (ESARDA), all parties agreed that the regional working group initially established under the DOE/ABACC cooperation should be expanded to an international working group. The purpose of the international working group is to provide a forum to exchange information, discuss technical developments, and validate and test the various codes. However, progress to formally establish the working has been slowed by a lack of dedicated funding and competing priorities within the various international organizations. Recently, the ESARDA Nondestructive Assay Working Group established a dedicated website for the International Working Group on Gamma Spectrometry Techniques (1 WG-GST). In this paper, we will explore specific steps that should be taken to strengthen this working group's ability to affect development of a common testing platform and address concerns regarding applicability, sustainability and version control for these important codes.

  13. 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.

  14. Measurement of the isotope fractionation associated with diffusion of carbon dioxide in aqueous solution

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1984-01-01

    An isotope ratio method has been developed which permits measurement of the isotope fractionation associated with diffusion of solutes in solution. Diffusion is conducted in a diaphragm cell of the type usually used for tracer diffusion measurements. The difference in isotopic composition of the solute before and after the diffusion process is measured by means of an isotope ratio mass spectrometer. This difference is then used to calculate the ratio of diffusion coefficients for the two isotopic species. By this method the isotope fractionation associated with diffusion of CO/sub 2/ dissolved in water has been found to be D(/sup 12/CO/sub 2/)/D(/sup 13/CO/sub 2/) = 1.0007 +/- 0.0002 at 25/sup 0/C. The same series of experiments also produced a value of 1.0011 for the ratio of solubilities of /sup 12/CO/sub 2/ and /sup 13/CO/sub 2/ in water at 30/sup 0/C, in excellent agreement with the published value. 23 references, 1 table.

  15. Carbon isotope fractionation in plants. Final technical report, June 1, 1983-May 31, 1986

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1986-09-01

    Plants fractionate carbon isotopes during photosynthesis in ways which reflect photosynthetic pathway and environment. The object of our work is to develop methods for using this isotope fractionation to give information about how the components of the carbon fixation process (diffusion, carboxylation, etc.) vary with species, environment, and other variables. These studies provide important information regarding environmental control of the efficiency of photosynthesis as well as information regarding changes in photosynthesis which can be expected in coming years as atmospheric carbon dioxide levels increase. To this end, we have developed quantitative models for carbon isotope fractionation which describe this process in terms of rates of diffusion, carboxylation, and other steps. We have developed experimental approaches which focus on the initial events in carbon dioxide fixation and enable us to determine the relative rates of the various individual processes involved. Our approaches are unique in that they provide a view of the carbon isotope fractionation process over a period of a few hours, whereas combustion methods used by previous investigators provide only a long-term view of the carbon isotope fractionation process. We have also developed other methods using stable isotopes which rely on NMR and mass spectral measurements to study plant metabolism. 61 refs., 5 figs., 4 tabs.

  16. 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.

  17. 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.

  18. Development of NDA instruments for the Los Alamos SIS (Special Isotope Separation) Facility

    SciTech Connect (OSTI)

    Li, T.K.; Rinard, P.M.; Schneider, C.M.; Atencio, J.D.; Hyman, D.H.; Kroncke, K.E.; Painter, J.; Siebelist, R.; Holbrooks, O.; Halbig, J.K.

    1989-01-01

    The Los Alamos Special Isotope Separation Facility produces special plutonium isotopes and converts plutonium scrap by using the molecular laser isotope separation (MLIS) process in a gaseous plutonium hexafluoride (PuF/sub 6/) phase. To provide important process-development and accountability information, we have developed and installed four nondestructive assay (NDA) instruments for that facility. These instruments are (1) an in-line plutonium isotopic analysis system to measure plutonium isotopes in gaseous, solid, and liquid phases, (2) an in-line sodium iodide (NaI) monitoring system consisting of six 2-in. by 2-in., two 2-in. by 24-in., and one 2-in. by 22-in. NaI detectors at specified components (a feed bottle, a feed-transfer cold trap, a compressor, a heat exchanger, a collector, a nozzle prefilter, and a tails cold trap) in the flow loop, (3) a portable high-resolution germanium gamma-ray system for plutonium isotopic analysis, and (4) a portable NaI gamma-ray holdup monitor. This paper discusses the measurement principles, hardware and software designs, and performance associated with these NDA instruments. 2 refs, 11 figs., 2 tabs.

  19. Geothermometry At Walker-Lane Transitional Zone Region (Shevenell...

    Open Energy Info (EERE)

    De Rocher, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At Walker-Lane Transitional Zone Region (Shevenell & De Rocher,...

  20. Geothermometry At Mt Princeton Hot Springs Geothermal Area (Pearl...

    Open Energy Info (EERE)

    Et Al., 1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At Mt Princeton Hot Springs Geothermal Area (Pearl, Et Al., 1976)...

  1. Geothermometry At Long Valley Caldera Geothermal Area (Mariner...

    Open Energy Info (EERE)

    Mariner & Willey, 1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermometry At Long Valley Caldera Geothermal Area (Mariner & Willey,...

  2. Fabrication of control rods for the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Sease, J.D.

    1998-03-01

    The High Flux Isotope Reactor (HFIR) is a research-type nuclear reactor that was designed and built in the early 1960s and has been in continuous operation since its initial criticality in 1965. Under current plans, the HFIR is expected to continue in operation until 2035. This report updates ORNL/TM-9365, Fabrication Procedure for HFIR Control Plates, which was mainly prepared in the early 1970's but was not issued until 1984, and reflects process changes, lessons learned in the latest control rod fabrication campaign, and suggested process improvements to be considered in future campaigns. Most of the personnel involved with the initial development of the processes and in part campaigns have retired or will retire soon. Because their unlikely availability in future campaigns, emphasis has been placed on providing some explanation of why the processes were selected and some discussions about the importance of controlling critical process parameters. Contained in this report is a description of the function of control rods in the reactor, the brief history of the development of control rod fabrication processes, and a description of procedures used in the fabrication of control rods. A listing of the controlled documents and procedures used in the last fabrication campaigns is referenced in Appendix A.

  3. Atomic parity nonconservation and neutron radii in cesium isotopes

    E-Print Network [OSTI]

    B. Q. Chen; P. Vogel

    1993-03-05

    The interpretation of future precise experiments on atomic parity violation in terms of parameters of the Standard Model could be hampered by uncertainties in the atomic and nuclear structure. While the former can be overcome by measurement in a series of isotopes, the nuclear structure requires knowledge of the neutron density. We use the nuclear Hartree-Fock method, which includes deformation effects, to calculate the proton and neutron densities in {125}Cs-{139}Cs. We argue that the good agreement with the experimental charge radii, binding energies, and ground state spins signifies that the phenomenological nuclear force and the method of calculation that we use is adequate. Based on this agreement, and on calculations involving different effective interactions, we estimate the uncertainties in the differences of the neutron radii delta_{N,N'} and conclude that they cause uncertainties in the ratio of weak charges, the quantities determined in the atomic parity nonconservation experiments, of less than 10^{-3}. Such an uncertainty is smaller than the anticipated experimental error.

  4. Design of the beryllium window for Brookhaven Linac Isotope Producer

    SciTech Connect (OSTI)

    Nayak, S.; Mapes, M.; Raparia, D.

    2015-11-01

    In the Brookhaven Linac Isotope Producer (BLIP) beam line, there were two Beryllium (Be) windows with an air gap to separate the high vacuum upstream side from low vacuum downstream side. There had been frequent window failures in the past which affected the machine productivity and increased the radiation dose received by worker due to unplanned maintenance. To improve the window life, design of Be window is reexamined. Detailed structural and thermal simulations are carried out on Be window for different design parameters and loading conditions to come up with better design to improve the window life. The new design removed the air gap and connect the both beam lines with a Be window in-between. The new design has multiple advantages such as 1) reduces the beam energy loss (because of one window with no air gap), 2) reduces air activation due to nuclear radiation and 3) increased the machine reliability as there is no direct pressure load during operation. For quick replacement of this window, an aluminum bellow coupled with load binder was designed. There hasnt been a single window failure since the new design was implemented in 2012.

  5. 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.

  6. Big Bang Nucleosynthesis and the Helium Isotope Ratio

    E-Print Network [OSTI]

    Cooke, Ryan

    2015-01-01

    The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of this quantity tentatively support new physics beyond the standard model but, historically, this method has suffered from hidden systematic uncertainties. In this letter, I show that a combined measurement of the primordial deuterium abundance and the primordial helium isotope ratio has the potential to provide a complementary and reliable probe of new physics beyond the standard model. Using the recent determination of the primordial deuterium abundance and assuming that the measured pre-solar 3He/4He meteoritic abundance reflects the primordial value, a bound can be placed on the effective number of neutrino species, Neff(BBN) = 3.01 (+0.95 -0.76, with 95 per cent confidence). Although this value of Neff supports the standard model, it is presently unclear if the pre-solar 3...

  7. Positive correlation between Li and Mg isotope ratios in the river waters of the Mackenzie Basin challenges the interpretation of apparent isotopic

    E-Print Network [OSTI]

    Paytan, Adina

    Positive correlation between Li and Mg isotope ratios in the river waters of the Mackenzie Basin a Institut de Physique du Globe de Paris, Sorbonne Paris Cite, Univ Paris Diderot, UMR 7154 CNRS, F-75005 Paris, France b Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB23EQ

  8. On the usage of electron beam as a tool to produce radioactive isotopes in photo-nuclear reactions

    E-Print Network [OSTI]

    G. G. Bunatian; V. G. Nikolenko; A. B. Popov

    2010-12-22

    We treat the bremsstrahlung induced by initial electron beam in converter, and the production of a desirable radio-isotope due to the photo-nuclear reaction caused by this bremsstrahlung. By way of illustration, the yield of a number of some, the most in practice applicable, radio-isotopes is evaluated. The acquired findings persuade us that usage of modern electron accelerators offers a practicable way to produce the radio-isotopes needful nowadays for various valuable applications in the nuclear medicine.

  9. ZIRCONIUMHAFNIUM ISOTOPE EVIDENCE FROM METEORITES FOR THE DECOUPLED SYNTHESIS OF LIGHT AND HEAVY NEUTRON-RICH NUCLEI

    SciTech Connect (OSTI)

    Akram, W.; Schnbchler, M.; Sprung, P.; Vogel, N.

    2013-11-10

    Recent work based on analyses of meteorite and terrestrial whole-rock samples showed that the r- and s- process isotopes of Hf were homogeneously distributed throughout the inner solar system. We report new Hf isotope data for Calcium-Aluminum-rich inclusions (CAIs) of the CV3 carbonaceous chondrite Allende, and novel high-precision Zr isotope data for these CAIs and three carbonaceous chondrites (CM, CO, CK). Our Zr data reveal enrichments in the neutron-rich isotope {sup 96}Zr (?1? in {sup 96}Zr/{sup 90}Zr) for bulk chondrites and CAIs (?2?). Potential isotope effects due to incomplete sample dissolution, galactic and cosmic ray spallation, and the nuclear field shift are assessed and excluded, leading to the conclusion that the {sup 96}Zr isotope variations are of nucleosynthetic origin. The {sup 96}Zr enrichments are coupled with {sup 50}Ti excesses suggesting that both nuclides were produced in the same astrophysical environment. The same CAIs also exhibit deficits in r-process Hf isotopes, which provides strong evidence for a decoupling between the nucleosynthetic processes that produce the light (A ? 130) and heavy (A > 130) neutron-rich isotopes. We propose that the light neutron-capture isotopes largely formed in Type II supernovae (SNeII) with higher mass progenitors than the supernovae that produced the heavy r-process isotopes. In the context of our model, the light isotopes (e.g. {sup 96}Zr) are predominantly synthesized via charged-particle reactions in a high entropy wind environment, in which Hf isotopes are not produced. Collectively, our data indicates that CAIs sampled an excess of materials produced in a normal mass (12-25 M{sub ?}) SNII.

  10. Where does streamwater come from in low-relief forested watersheds? A dual-isotope approach

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

    Klaus, J.; McDonnell, J. J.; Jackson, C. R.; Du, E.; Griffiths, N. A.

    2015-01-08

    The time and geographic sources of streamwater in low-relief watersheds are poorly understood. This is partly due to the difficult combination of low runoff coefficients and often damped streamwater isotopic signals precluding traditional hydrograph separation and convolution integral approaches. Here we present a dual-isotope approach involving 18O and 2H of water in a low-angle forested watershed to determine streamwater source components and then build a conceptual model of streamflow generation. We focus on three headwater lowland sub-catchments draining the Savannah River Site in South Carolina, USA. Our results for a 3-year sampling period show that the slopes of the meteoricmorewater lines/evaporation water lines (MWLs/EWLs) of the catchment water sources can be used to extract information on runoff sources in ways not considered before. Our dual-isotope approach was able to identify unique hillslope, riparian and deep groundwater, and streamflow compositions. Thus, the streams showed strong evaporative enrichment compared to the local meteoric water line (?2H = 7.15 ?18O +9.28) with slopes of 2.52, 2.84, and 2.86. Based on the unique and unambiguous slopes of the EWLs of the different water cycle components and the isotopic time series of the individual components, we were able to show how the riparian zone controls baseflow in this system and how the riparian zone "resets" the stable isotope composition of the observed streams in our low-angle, forested watersheds. Although this approach is limited in terms of quantifying mixing percentages between different end-members, our dual-isotope approach enabled the extraction of hydrologically useful information in a region with little change in individual isotope time series.less

  11. Strontium Isotope Study of Coal Untilization By-products Interacting with Environmental Waters

    SciTech Connect (OSTI)

    Spivak-Birndorf, Lev J; Stewart, Brian W; Capo, Rosemary C; Chapman, Elizabeth C; Schroeder, Karl T; Brubaker, Tonya M

    2011-09-01

    Sequential leaching experiments on coal utilization by-products (CUB) were coupled with chemical and strontium (Sr) isotopic analyses to better understand the influence of coal type and combustion processes on CUB properties and the release of elements during interaction with environmental waters during disposal. Class C fly ash tended to release the highest quantity of minor and trace elementsincluding alkaline earth elements, sodium, chromium, copper, manganese, lead, titanium, and zincduring sequential extraction, with bottom ash yielding the lowest. Strontium isotope ratios ({sup 87}Sr/{sup 86}Sr) in bulk-CUB samples (total dissolution of CUB) are generally higher in class F ash than in class C ash. Bulk-CUB ratios appear to be controlled by the geologic source of the mineral matter in the feed coal, and by Sr added during desulfurization treatments. Leachates of the CUB generally have Sr isotope ratios that are different than the bulk value, demonstrating that Sr was not isotopically homogenized during combustion. Variations in the Sr isotopic composition of CUB leachates were correlated with mobility of several major and trace elements; the data suggest that arsenic and lead are held in phases that contain the more radiogenic (high-{sup 87}Sr/{sup 86}Sr) component. A changing Sr isotope ratio of CUB-interacting waters in a disposal environment could forecast the release of certain strongly bound elements of environmental concern. This study lays the groundwork for the application of Sr isotopes as an environmental tracer for CUBwater interaction.

  12. Isotope Enrichment Detection by Laser Ablation - Dual Tunable Diode Laser Absorption Spectrometry

    SciTech Connect (OSTI)

    Anheier, Norman C.; Bushaw, Bruce A.

    2009-07-01

    The rapid global expansion of nuclear energy is motivating the expedited development of new safeguards technology to mitigate potential proliferation threats arising from monitoring gaps within the uranium enrichment process. Current onsite enrichment level monitoring methods are limited by poor sensitivity and accuracy performance. Offsite analysis has better performance, but this approach requires onsite hand sampling followed by time-consuming and costly post analysis. These limitations make it extremely difficult to implement comprehensive safeguards accounting measures that can effectively counter enrichment facility misuse. In addition, uranium enrichment by modern centrifugation leads to a significant proliferation threat, since the centrifuge cascades can quickly produce a significant quantity of highly enriched uranium (HEU). The Pacific Northwest National Laboratory is developing an engineered safeguards approach having continuous aerosol particulate collection and uranium isotope analysis to provide timely detection of HEU production in a low enriched uranium facility. This approach is based on laser vaporization of aerosol particulate samples, followed by wavelength tuned laser diode spectroscopy, to characterize the 235U/238U isotopic ratio by subtle differences in atomic absorption wavelengths arising from differences in each isotopes nuclear mass, volume, and spin (hyperfine structure for 235U). Environmental sampling media is introduced into a small, reduced pressure chamber, where a focused pulsed laser vaporizes a 10 to 20-m sample diameter. The ejected plasma forms a plume of atomic vapor. A plume for a sample containing uranium has atoms of the 235U and 238U isotopes present. Tunable diode lasers are directed through the plume to selectively excite each isotope and their presence is detected by monitoring absorbance signals on a shot-to-shot basis. Single-shot detection sensitivity approaching the femtogram range and abundance uncertainty less than 10% have been demonstrated with measurements on surrogate materials. In this paper we present measurement results on samples containing background materials (e.g., dust, minerals, soils) laced with micron-sized target particles having isotopic ratios ranging from 1 to 50%.

  13. Using Stable Isotopes of Nitrogen and Oxygen as Environmental Indicators of Nitrogen Deposition in the Sonoran Desert

    E-Print Network [OSTI]

    Bell, Michael David

    2012-01-01

    the Denitrifier Method. Analytical Chemistry 74:4905-4912.Isotopic Analyses. Analytical Chemistry 83:1850-1856.the Denitrifier Method. Analytical Chemistry 74:4905-4912.

  14. Chemical and isotopic properties and origin of coarse airborne particles collected by passive samplers in industrial, urban, and rural environments

    E-Print Network [OSTI]

    Short, Daniel

    Chemical and isotopic properties and origin of coarse airborne particles collected by passive vehicle and industrial emissions, coal combustion (e.g. cooking, heating, power plants) represents

  15. Effects of volcanism, crustal thickness, and large-scale faulting on the He isotope signatures of geothermal systems in Chile

    E-Print Network [OSTI]

    Morata, Dobson, P.F., B.M. Kennedy, M. Reich, P. Sanchez, and D.

    2014-01-01

    of the Cordon Caulle geothermal system, southern Chile,?volcanic centers and geothermal systems in the CVZ wereHelium isotopes in geothermal systems: Iceland, The Geysers,

  16. Extraction of short-lived zirconium and hafnium isotopes using crown ethers: A model system for the study of rutherfordium

    E-Print Network [OSTI]

    2005-01-01

    Extraction of short-lived zirconium and hafnium isotopesReceived: ; Accepted: Zirconium / Hafnium / Crown ether /The extraction of zirconium and hafnium from hydrochloric

  17. Isotope exchange kinetics in metal hydrides I : TPLUG model.

    SciTech Connect (OSTI)

    Larson, Rich; James, Scott Carlton; Nilson, Robert H.

    2011-05-01

    A one-dimensional isobaric reactor model is used to simulate hydrogen isotope exchange processes taking place during flow through a powdered palladium bed. This simple model is designed to serve primarily as a platform for the initial development of detailed chemical mechanisms that can then be refined with the aid of more complex reactor descriptions. The one-dimensional model is based on the Sandia in-house code TPLUG, which solves a transient set of governing equations including an overall mass balance for the gas phase, material balances for all of the gas-phase and surface species, and an ideal gas equation of state. An energy equation can also be solved if thermodynamic properties for all of the species involved are known. The code is coupled with the Chemkin package to facilitate the incorporation of arbitrary multistep reaction mechanisms into the simulations. This capability is used here to test and optimize a basic mechanism describing the surface chemistry at or near the interface between the gas phase and a palladium particle. The mechanism includes reversible dissociative adsorptions of the three gas-phase species on the particle surface as well as atomic migrations between the surface and the bulk. The migration steps are more general than those used previously in that they do not require simultaneous movement of two atoms in opposite directions; this makes possible the creation and destruction of bulk vacancies and thus allows the model to account for variations in the bulk stoichiometry with isotopic composition. The optimization code APPSPACK is used to adjust the mass-action rate constants so as to achieve the best possible fit to a given set of experimental data, subject to a set of rigorous thermodynamic constraints. When data for nearly isothermal and isobaric deuterium-to-hydrogen (D {yields} H) and hydrogen-to-deuterium (H {yields} D) exchanges are fitted simultaneously, results for the former are excellent, while those for the latter show pronounced deviations at long times. These discrepancies can be overcome by postulating the presence of a surface poison such as carbon monoxide, but this explanation is highly speculative. When the method is applied to D {yields} H exchanges intentionally poisoned by known amounts of CO, the fitting results are noticeably degraded from those for the nominally CO-free system but are still tolerable. When TPLUG is used to simulate a blowdown-type experiment, which is characterized by large and rapid changes in both pressure and temperature, discrepancies are even more apparent. Thus, it can be concluded that the best use of TPLUG is not in simulating realistic exchange scenarios, but in extracting preliminary estimates for the kinetic parameters from experiments in which variations in temperature and pressure are intentionally minimized.

  18. Isotope separation by selective charge conversion and field deflection

    DOE Patents [OSTI]

    Hickman, Robert G. (Livermore, CA)

    1978-01-01

    A deuterium-tritium separation system wherein a source beam comprised of positively ionized deuterium (D.sup.+) and tritium (T.sup.+) is converted at different charge-exchange cell sections of the system to negatively ionized deuterium (D.sup.-) and tritium (T.sup.-). First, energy is added to the beam to accelerate the D.sup.+ ions to the velocity that is optimum for conversion of the D.sup.+ ions to D.sup.- ions in a charge-exchange cell. The T.sup.+ ions are accelerated at the same time, but not to the optimum velocity since they are heavier than the D.sup.+ ions. The T.sup.+ ions are, therefore, not converted to T.sup.- ions when the D.sup.+ ions are converted to D.sup.- ions. This enables effective separation of the beam by deflection of the isotopes with an electrostatic field, the D.sup.- ions being deflected in one direction and the T.sup.+ ions being deflected in the opposite direction. Next, more energy is added to the deflected beam of T.sup.+ ions to bring the T.sup.+ ions to the optimum velocity for their conversion to T.sup.- ions. In a particular use of the invention, the beams of D.sup.- and T.sup.- ions are separately further accelerated and then converted to energetic neutral particles for injection as fuel into a thermonuclear reactor. The reactor exhaust of D.sup.+ and T.sup.+ and the D.sup.+ and T.sup.+ that was not converted in the respective sections is combined with the source beam and recycled through the system to increase the efficiency of the system.

  19. High Flux Isotope Reactor cold neutron source reference design concept

    SciTech Connect (OSTI)

    Selby, D.L.; Lucas, A.T.; Hyman, C.R.

    1998-05-01

    In February 1995, Oak Ridge National Laboratory`s (ORNL`s) deputy director formed a group to examine the need for upgrades to the High Flux Isotope Reactor (HFIR) system in light of the cancellation of the Advanced neutron Source Project. One of the major findings of this study was that there was an immediate need for the installation of a cold neutron source facility in the HFIR complex. In May 1995, a team was formed to examine the feasibility of retrofitting a liquid hydrogen (LH{sub 2}) cold source facility into an existing HFIR beam tube. The results of this feasibility study indicated that the most practical location for such a cold source was the HB-4 beam tube. This location provides a potential flux environment higher than the Institut Laue-Langevin (ILL) vertical cold source and maximizes the space available for a future cold neutron guide hall expansion. It was determined that this cold neutron beam would be comparable, in cold neutron brightness, to the best facilities in the world, and a decision was made to complete a preconceptual design study with the intention of proceeding with an activity to install a working LH{sub 2} cold source in the HFIR HB-4 beam tube. During the development of the reference design the liquid hydrogen concept was changed to a supercritical hydrogen system for a number of reasons. This report documents the reference supercritical hydrogen design and its performance. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and testing, (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the conceptual design phase and establishes the baseline reference concept.

  20. Uranium isotopes in ground water as a prospecting technique

    SciTech Connect (OSTI)

    Cowart, J.B.; Osmond, J.K.

    1980-02-01

    The isotopic concentrations of dissolved uranium were determined for 300 ground water samples near eight known uranium accumulations to see if new approaches to prospecting could be developed. It is concluded that a plot of /sup 234/U//sup 238/U activity ratio (A.R.) versus uranium concentration (C) can be used to identify redox fronts, to locate uranium accumulations, and to determine whether such accumulations are being augmented or depleted by contemporary aquifer/ground water conditions. In aquifers exhibiting flow-through hydrologic systems, up-dip ground water samples are characterized by high uranium concentration values (> 1 to 4 ppB) and down-dip samples by low uranium concentration values (less than 1 ppB). The boundary between these two regimes can usually be identified as a redox front on the basis of regional water chemistry and known uranium accumulations. Close proximity to uranium accumulations is usually indicated either by very high uranium concentrations in the ground water or by a combination of high concentration and high activity ratio values. Ground waters down-dip from such accumulations often exhibit low uranium concentration values but retain their high A.R. values. This serves as a regional indicator of possible uranium accumulations where conditions favor the continued augmentation of the deposit by precipitation from ground water. Where the accumulation is being dispersed and depleted by the ground water system, low A.R. values are observed. Results from the Gulf Coast District of Texas and the Wyoming districts are presented.