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1

Mass-Independent Isotope Effects  

Science Journals Connector (OSTI)

Scientific interests: ESR and NMR spectroscopies, molecular magnets, mechanisms of chemical and biochemical reactions, spin physics and chemistry, isotopes and isotope effects in chemistry and biochemistry. ... Another mass-independent isotope effect was detected in 1983 as a deviation of isotopic distribution in reaction products from that which would be expected from the mass-dependent isotope effect. ... Later, Nomura et al.(92) have found isotopic 233U anomaly in the U4+–U6+ exchange reaction; they noted that the isotope effect was correlated with isotope shifts in the atomic spectra of uranium isotopes. ...

Anatoly L. Buchachenko

2013-01-09T23:59:59.000Z

2

Advanced Mass Spectrometers for Hydrogen Isotope Analyses  

SciTech Connect (OSTI)

This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.

Chastagner, P.

2001-08-01T23:59:59.000Z

3

Stable Isotope, Site-Specific Mass Tagging For Protein Identification  

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

Stable Isotope, Site-Specific Mass Tagging For Protein Identification Stable Isotope, Site-Specific Mass Tagging For Protein Identification Proteolytic peptide mass mapping as...

4

On neutron numbers and atomic masses  

Science Journals Connector (OSTI)

On neutron numbers and atomic masses ... Assigning neutron numbers, correct neutron numbers, and atomic masses and nucleon numbers. ...

R. Heyrovská

1992-01-01T23:59:59.000Z

5

Particle Number & Particulate Mass Emissions Measurements on...  

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

Number & Particulate Mass Emissions Measurements on a 'Euro VI' Heavy-duty Engine using the PMP Methodologies Particle Number & Particulate Mass Emissions Measurements on a 'Euro...

6

Penning trap mass measurements on nobelium isotopes  

SciTech Connect (OSTI)

The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt allows accurate mass measurements of radionuclides, produced in fusion-evaporation reactions and separated by the velocity filter SHIP from the primary beam. Recently, the masses of the three nobelium isotopes {sup 252-254}No were determined. These are the first direct mass measurements of transuranium elements, which provide new anchor points in this region. The heavy nuclides were produced in cold-fusion reactions by irradiating a PbS target with a {sup 48}Ca beam, resulting in production rates of the nuclei of interest of about one atom per second. In combination with data from decay spectroscopy our results are used to perform a new atomic-mass evaluation in this region.

Dworschak, M.; Block, M.; Ackermann, D.; Herfurth, F.; Hessberger, F. P.; Hofmann, S.; Vorobyev, G. K. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Audi, G. [CSNSM-IN2P3-CNRS, F-91405 Orsay-Campus (France); Blaum, K. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Ruprecht-Karls-Universitaet, D-69120 Heidelberg (Germany); Droese, C.; Marx, G.; Schweikhard, L. [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, D-17487 Greifswald (Germany); Eliseev, S.; Ketter, J. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Fleckenstein, T. [Justus-Liebig-Universitaet Giessen, D-35390 Giessen (Germany); Haettner, E.; Plass, W. R.; Scheidenberger, C. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Justus-Liebig-Universitaet Giessen, D-35390 Giessen (Germany); Ketelaer, J. [Johannes Gutenberg-Universitaet, Institut fuer Physik, D-55099 Mainz (Germany); Kluge, H.-J. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Ruprecht-Karls-Universitaet, D-69120 Heidelberg (Germany)

2010-06-15T23:59:59.000Z

7

Stable Isotope, Site-Specific Mass Tagging For Protein Identification  

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

Stable Isotope, Site-Specific Mass Tagging For Protein Stable Isotope, Site-Specific Mass Tagging For Protein Identification Stable Isotope, Site-Specific Mass Tagging For Protein Identification Proteolytic peptide mass mapping as measured by mass spectrometry provides an important method for the identification of proteins, which are usually identified by matching the measured and calculated m/z values of the proteolytic peptides. Available for thumbnail of Feynman Center (505) 665-9090 Email Stable Isotope, Site-Specific Mass Tagging For Protein Identification Proteolytic peptide mass mapping as measured by mass spectrometry provides an important method for the identification of proteins, which are usually identified by matching the measured and calculated m/z values of the proteolytic peptides. A unique identification is, however, heavily

8

ISOTOPE FRACTIONATION Isotopes are atoms whose nuclei contain the same number of protons but a different number of neutrons. The  

E-Print Network [OSTI]

the most abundant isotope appears in the denominator: b R = b E / a E (stable boron isotopes = , [ ] [ ] [ ] [ ]OOCOOC2 OOCOOC2 O 16181616 16181818 CO 18 2 + + = . The isotopic composition, , of a sample, determined____________________________ ISOTOPE FRACTIONATION ____________________________ Isotopes are atoms

Zeebe, Richard E.

9

Determination of boron isotope ratios in geological materials by inductively coupled plasma mass spectrometry  

Science Journals Connector (OSTI)

Determination of boron isotope ratios in geological materials by inductively coupled plasma mass spectrometry ... Isotope dilution analysis using flow injection inductively coupled plasma mass spectrometry was applied to determine low boron contents in iron and steel samples. ...

D. Conrad Gregoire

1987-10-01T23:59:59.000Z

10

PYRO: New capability for isotopic mass tracking in pyroprocess simulation  

SciTech Connect (OSTI)

A new computational code package called PYRO has been developed to support the IFR fuel recycle demonstration project in the HFEF/S facility at ANL-W. The basic pyrochemical code PYRO1-1 models the atomic mass flows and phase compositions of 48 essential chemical elements involved in the pyroprocess. It has been extended to PYRO1-2 by linking with the ORIGEN code to track more than 1000 isotopic species, their radioactive decays, and related phenomena. This paper first describes the pyroprocess to be modeled and the pyrochemical capability that has been implemented in PYRO1-1, and then gives a full account on the algorithm of extending it to PYRO1-2 for isotopic mass tracking. Results from several scoping and simulation runs will be discussed to illustrate the significance of modeling in-process radioactive decays. 16 refs., 8 figs., 2 tabs.

Liaw, J.R.; Ackerman, J.P.

1990-01-01T23:59:59.000Z

11

Raman spectroscopic and mass spectrometric investigations of the hydrogen isotopes and isotopically labelled methane  

SciTech Connect (OSTI)

Suitable analytical methods must be tested and developed for monitoring the individual process steps within the fuel cycle of a fusion reactor and for tritium accountability. The utility of laser-Raman spectroscopy accompanied by mass spectrometry with an Omegatron was investigated using the analysis of all hydrogen isotopes and isotopically labeled methanes as an example. The Omegatron is useful for analyzing all hydrogen isotopes mixed with the stable helium isotopes. The application of this mass spectrometer were demonstrated by analyzing mixtures of deuterated methanes. In addition, it was employed to study the radiochemical Witzbach exchange reaction between tritium and methanes. A laser-Raman spectrometer was designed for analysis of tritium-containing gases and was built from individual components. A tritium-compatible, metal-sealed Raman cuvette having windows with good optical properties and additional means for measuring the stray light was first used successfully in this work. The Raman spectra of the hydrogen isotopes were acquired in the pure rotation mode and in the rotation-vibration mode and were used for on. The deuterated methanes were measured by Raman spectroscopy, the wavenumbers determined were assigned to the corresponding vibrations, and the wavenumbers for the rotational fine-structure were summarized in tables. The fundamental Vibrations of the deuterated methanes produced Witzbach reactions were detected and assigned. The fundamental vibrations of the molecules were obtained with Raman spectroscopy for the first time in this work. The @-Raman spectrometer assembled is well suited for the analysis of tritium- containing gases and is practical in combination with mass spectrometry using an Omegatron, for studying gases used in fusion.

Jewett, J.R., Fluor Daniel Hanford

1997-02-24T23:59:59.000Z

12

Determination of boron traces in rye grass BCR 281 by isotope dilution mass spectrometry  

Science Journals Connector (OSTI)

A method for the isotope dilution mass spectrometric (IDMS) determination of boron in rye grass at the 5 ?g...?1 level has been developed. The mass spectrometric measurements are performed using negative thermal ...

A. Lamberty; V. Holland; A. Verbruggen…

1988-01-01T23:59:59.000Z

13

High-accuracy mass measurements of neutron-rich Kr isotopes  

Science Journals Connector (OSTI)

The atomic masses of the neutron-rich krypton isotopes Kr84,86-95 have been determined with the tandem Penning trap mass spectrometer ISOLTRAP with uncertainties ranging from 20 to 220 ppb. The masses of the short-lived isotopes Kr94 and Kr95 were measured for the first time. The masses of the radioactive nuclides Kr89 and Kr91 disagree by 4 and 6 standard deviations, respectively, from the present Atomic-Mass Evaluation database. The resulting modification of the mass surface with respect to the two-neutron separation energies as well as implications for mass models and stellar nucleosynthesis are discussed.

P. Delahaye; G. Audi; K. Blaum; F. Carrel; S. George; F. Herfurth; A. Herlert; A. Kellerbauer; H.-J. Kluge; D. Lunney; L. Schweikhard; C. Yazidjian

2006-09-28T23:59:59.000Z

14

Direct mass measurements of neutron-rich zirconium isotopes up to Zr104  

Science Journals Connector (OSTI)

Atomic masses of radioactive zirconium isotopes from Zr96 to Zr104 have been measured with a relative accuracy of ?5×10?7 using a Penning trap coupled to the ion guide isotope separator on-line system. The obtained two-neutron separation energies show strong local correlation in relation to the shape change and shape coexistence between N=58 and 60.

S. Rinta-Antila; S. Kopecky; V. S. Kolhinen; J. Hakala; J. Huikari; A. Jokinen; A. Nieminen; J. Äystö; J. Szerypo

2004-07-14T23:59:59.000Z

15

Maximum stellar mass versus cluster membership number revisited  

E-Print Network [OSTI]

We have made a new compilation of observations of maximum stellar mass versus cluster membership number from the literature, which we analyse for consistency with the predictions of a simple random drawing hypothesis for stellar mass selection in clusters. Previously, Weidner and Kroupa have suggested that the maximum stellar mass is lower, in low mass clusters, than would be expected on the basis of random drawing, and have pointed out that this could have important implications for steepening the integrated initial mass function of the Galaxy (the IGIMF) at high masses. Our compilation demonstrates how the observed distribution in the plane of maximum stellar mass versus membership number is affected by the method of target selection; in particular, rather low n clusters with large maximum stellar masses are abundant in observational datasets that specifically seek clusters in the environs of high mass stars. Although we do not consider our compilation to be either complete or unbiased, we discuss the method by which such data should be statistically analysed. Our very provisional conclusion is that the data is not indicating any striking deviation from the expectations of random drawing.

Th. Maschberger; C. J. Clarke

2008-08-29T23:59:59.000Z

16

Occupation number-based energy functional for nuclear masses  

E-Print Network [OSTI]

We develop an energy functional with shell-model occupations as the relevant degrees of freedom and compute nuclear masses across the nuclear chart. The functional is based on Hohenberg-Kohn theory with phenomenologically motivated terms. A global fit of the 17-parameter functional to nuclear masses yields a root-mean-square deviation of \\chi = 1.31 MeV. Nuclear radii are computed within a model that employs the resulting occupation numbers.

M. Bertolli; T. Papenbrock; S. Wild

2011-10-19T23:59:59.000Z

17

Number-conserving approach to the pairing problem: Application to Kr and Sn isotopic chains  

Science Journals Connector (OSTI)

The recently proposed symmetry-conserving energy density functional approach [G. Hupin, D. Lacroix, and M. Bender, Phys. Rev. C 84, 014309 (2011)] is applied to perform variation after projection onto the good particle number using the Skyrme interaction, including density-dependent terms. We propose a simplification to reduce the numerical effort to perform the variation. We present a systematic study of the Kr and Sn isotopic chains. This approach leads to nonzero pairing in magic nuclei and a global enhancement of the pairing gap compared to the original theory, which breaks particle number symmetry.

Guillaume Hupin and Denis Lacroix

2012-08-17T23:59:59.000Z

18

The mid-Cretaceous water bearer: isotope mass balance quantication of the Albian hydrologic cycle  

E-Print Network [OSTI]

. Witzke a;b;c a Department of Geoscience, University of Iowa, Iowa City, IA 52242-1379, USA b Center of the equable `greenhouse' Albian Stage in the KWIB. The mass balance model tracks the evolving isotopic conditions. Ã? 2002 Elsevier Science B.V. All rights reserved. Keywords: sphaerosiderites; Cretaceous; oxygen

González, Luis A.

19

Improving boron isotope ratio measurement precision with quadrupole inductively coupled plasma-mass spectrometry  

Science Journals Connector (OSTI)

A method was developed to improve the precision of inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) for the determination of boron isotope ratios (11B/10B) in various environmental materials including seawater. This approach is based on the common analyte internal standardization (CAIS) chemometric algorithm. The sample solution obtained after digestion is spiked with lithium, and both 7Li/6Li and 11B/10B values are measured using long-counting periods (20 min). The CAIS algorithm corrects the measured 11B/10B values for (a) statistical fluctuations resulting from short-term noise; (b) drift in 11B-to-10B ratio as a result of long-term deviation in instrumental parameters likely to occur during long counting times; (c) change in 11B-to-10B ratio caused by variation in matrix elements concentrations; and (d) drift in mass bias correction factor. Comparing boron isotopic ratios in seawater measured by conventional and the new isotope ratio methods validates the procedure. A synthetic isotopic mixture of boron SRM 951 and enriched 10B SRM 952 also was examined. The CAIS method provided a measured boron isotopic ratio precision of 0.05% R.S.D. while eliminating 5.1% matrix concentration error and 0.25% instrumental drift error.

Assad Al-Ammar; Eva Reitznerová; Ramon M. Barnes

2000-01-01T23:59:59.000Z

20

SIMULTANEOUS CONSTRAINTS ON THE NUMBER AND MASS OF RELATIVISTIC SPECIES  

SciTech Connect (OSTI)

Recent indications from both particle physics and cosmology suggest the possible existence of more than three neutrino species. In cosmological analyses the effects of neutrino mass and number of species can in principle be disentangled for fixed cosmological parameters. However, since we do not have perfect measurements of the standard {Lambda} cold dark matter model parameters, some correlation remains between the neutrino mass and number of species, and both parameters should be included in the analysis. Combining the newest observations of several cosmological probes (cosmic microwave background, large-scale structure, expansion rate), we obtain N {sub eff} = 3.58{sup +0.15} {sub -0.16}(68% CL){sup +0.55} {sub -0.53}(95% CL) and {Sigma}m {sub {nu}} < 0.60 eV(95% CL), which are currently the strongest constraints on N {sub eff} and {Sigma}m {sub {nu}} from an analysis including both parameters. The preference for N {sub eff} >3 is at the 2{sigma} level.

Riemer-Sorensen, Signe; Parkinson, David; Davis, Tamara M. [School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072 (Australia)] [School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072 (Australia); Blake, Chris, E-mail: signe@physics.uq.edu.au [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, VIC 3122 (Australia)] [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, VIC 3122 (Australia)

2013-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

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

SciTech Connect (OSTI)

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

Jayasekharan, T.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2013-02-05T23:59:59.000Z

22

Separation Of Uranium And Plutonium Isotopes For Measurement By Multi Collector Inductively Coupled Plasma Mass Spectroscopy  

SciTech Connect (OSTI)

Uranium (U) and plutonium (Pu) isotopes in coral soils, contaminated by nuclear weapons testing in the northern Marshall Islands, were isolated by ion-exchange chromatography and analyzed by mass spectrometry. The soil samples were spiked with {sup 233}U and {sup 242}Pu tracers, dissolved in minerals acids, and U and Pu isotopes isolated and purified on commercially available ion-exchange columns. The ion-exchange technique employed a TEVA{reg_sign} column coupled to a UTEVA{reg_sign} column. U and Pu isotope fractions were then further isolated using separate elution schemes, and the purified fractions containing U and Pu isotopes analyzed sequentially using multi-collector inductively coupled plasma mass spectrometer (MCICP-MS). High precision measurements of {sup 234}U/{sup 235}U, {sup 238}U/{sup 235}U, {sup 236}U/{sup 235}U, and {sup 240}Pu/{sup 239}Pu in soil samples were attained using the described methodology and instrumentation, and provide a basis for conducting more detailed assessments of the behavior and transfer of uranium and plutonium in the environment.

Martinelli, R E; Hamilton, T F; Williams, R W; Kehl, S R

2009-03-29T23:59:59.000Z

23

Isotope correlations for determining the isotopic composition of plutonium produced in research and power reactors using the experimental data obtained by alpha and mass spectrometry  

Science Journals Connector (OSTI)

Correlations have been developed for obtaining the isotopic composition of Pu produced in Indian research (CIRUS, DHRUVA) and power (PHWR) reactors. The experimental data obtained on 238Pu/(239Pu + 240Pu) alpha activity ratio using alpha spectrometry and on 240Pu/239Pu, 241Pu/239Pu, 242Pu/239Pu atom ratios by thermal ionisation mass spectrometry were used for developing isotope correlations.

S.K. Aggarwal; D. Alamelu

2005-01-01T23:59:59.000Z

24

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions  

Science Journals Connector (OSTI)

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions ... (1) A relatively large mass difference (10%) between the two isotopes and high volatility results in significant boron isotopic variation from ?70‰(2) to +75‰(3) in natural materials; thus, boron isotopes have numerous applications in geochemistry, isotope hydrology, oceanography, environmental sciences, cosmology, and nuclear technology. ... (2) Our method provided better long-term stability of NIST 951 standard compared to “Zoom Quad” mode when more than two isotopes were determined in addition to boron isotope. ...

Mao-yong He; Ying-kai Xiao; Zhang-dong Jin; Yun-qi Ma; Jun Xiao; Yan-ling Zhang; Chong-guang Luo; Fei Zhang

2013-05-29T23:59:59.000Z

25

Isotopic mass-dependence of metal cation diffusion coefficients in liquid water  

SciTech Connect (OSTI)

Isotope distributions in natural systems can be highly sensitive to the mass (m) dependence of solute diffusion coefficients (D) in liquid water. Isotope geochemistry studies routinely have assumed that this mass dependence either is negligible (as predicted by hydrodynamic theories) or follows a kinetic-theory-like inverse square root relationship (D {proportional_to} m{sup -0.5}). However, our recent experimental results and molecular dynamics (MD) simulations showed that the mass dependence of D is intermediate between hydrodynamic and kinetic theory predictions (D {proportional_to} m{sup -{beta}} with 0 {<=} {beta} < 0.2 for Li{sup +}, Cl{sup -}, Mg{sup 2+}, and the noble gases). In this paper, we present new MD simulations and experimental results for Na{sup +}, K{sup +}, Cs{sup +}, and Ca{sup 2+} that confirm the generality of the inverse power-law relation D {proportional_to} m{sup -{beta}}. Our new findings allow us to develop a general description of the influence of solute valence and radius on the mass dependence of D for monatomic solutes in liquid water. This mass dependence decreases with solute radius and with the magnitude of solute valence. Molecular-scale analysis of our MD simulation results reveals that these trends derive from the exponent {beta} being smallest for those solutes whose motions are most strongly coupled to solvent hydrodynamic modes.

Bourg, I.C.; Richter, F.M.; Christensen, J.N.; Sposito, G.

2009-01-11T23:59:59.000Z

26

Isotope pattern deconvolution for peptide mass spectrometry by non-negative least squares/least absolute deviation template matching  

Science Journals Connector (OSTI)

Identification of overlapping isotope patterns in mass spectrometric data is achieved using non-negative least squares/non-negative least absolute deviation regression, and is able to disentangle complicated overlaps of patterns.

Martin Slawski; Rene Hussong; Andreas Tholey; Thomas Jakoby; Barbara Gregorius; Andreas Hildebrandt; Matthias Hein

2012-11-08T23:59:59.000Z

27

Anomalous pairing vibration in neutron-rich Sn isotopes beyond the N=82 magic number  

E-Print Network [OSTI]

Two-neutron transfer associated with the pair correlation in superfluid neutron-rich nuclei is studied with focus on low-lying $0^+$ states in Sn isotopes beyond the N=82 magic number. We describe microscopically the two-neutron addition and removal transitions by means of the Skyrme-Hartree-Fock-Bogoliubov mean-field model and the continuum quasiparticle random phase approximation formulated in the coordinate space representation. It is found that the pair transfer strength for the transitions between the ground states becomes significantly large for the isotopes with $A \\ge 140$, reflecting very small neutron separation energy and long tails of the weakly bound $3p$ orbits. In $^{132-140}$Sn, a peculiar feature of the pair transfer is seen in transitions to low-lying excited $0^+$ states. They can be regarded as a novel kind of pair vibrational mode which is characterized by an anomalously long tail of the transition density extending to far outside of the nuclear surface, and a large strength comparable to that of the ground-state transitions. The presence of the weakly bound neutron orbits plays a central role for these anomalous behaviors.

Hirotaka Shimoyama; Masayuki Matsuo

2011-06-09T23:59:59.000Z

28

THE GENESIS SOLAR WIND CONCENTRATOR TARGET: MASS FRACTIONATION CHARACTERISED BY NE ISOTOPES  

SciTech Connect (OSTI)

The concentrator on Genesis provides samples of increased fluences of solar wind ions for precise determination of the oxygen isotopic composition of the solar wind. The concentration process caused mass fractionation as function of the radial target position. They measured the fractionation using Ne released by UV laser ablation along two arms of the gold cross from the concentrator target to compare measured Ne with modeled Ne. The latter is based on simulations using actual conditions of the solar wind during Genesis operation. Measured Ne abundances and isotopic composition of both arms agree within uncertainties indicating a radial symmetric concentration process. Ne data reveal a maximum concentration factor of {approx} 30% at the target center and a target-wide fractionation of Ne isotopes of 3.8%/amu with monotonously decreasing {sup 20}Ne/{sup 22}Ne ratios towards the center. The experimentally determined data, in particular the isotopic fractionation, differ from the modeled data. They discuss potential reasons and propose future attempts to overcome these disagreements.

WIENS, ROGER C. [Los Alamos National Laboratory; OLINGER, C. [Los Alamos National Laboratory; HEBER, V.S. [Los Alamos National Laboratory; REISENFELD, D.B. [Los Alamos National Laboratory; BURNETT, D.S. [Los Alamos National Laboratory; ALLTON, J.H. [Los Alamos National Laboratory; BAUR, H. [Los Alamos National Laboratory; WIECHERT, U. [Los Alamos National Laboratory; WIELER, R. [Los Alamos National Laboratory

2007-01-02T23:59:59.000Z

29

Definition: Isotopic Analysis | Open Energy Information  

Open Energy Info (EERE)

Analysis Analysis Jump to: navigation, search Dictionary.png Isotopic Analysis Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.[1] View on Wikipedia Wikipedia Definition Isotope analysis is the identification of isotopic signature, the distribution of certain stable isotopes and chemical elements within chemical compounds. This can be applied to a food web to make it possible to draw direct inferences regarding diet, trophic level, and subsistence. Isotope ratios are measured using mass spectrometry, which separates the different isotopes of an element on the basis of their mass-to-charge

30

Altered solar wind -magnetosphere interaction at low Mach numbers: coronal mass ejections  

E-Print Network [OSTI]

1 Altered solar wind - magnetosphere interaction at low Mach numbers: coronal mass ejections Benoit fundamental alterations of the solar wind ­ magnetosphere interaction that occur during low Mach number solar wind. We first show that low Mach number solar wind conditions are often characteristic of coronal mass

Boyer, Edmond

31

Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry  

E-Print Network [OSTI]

Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry

American Society for Testing and Materials. Philadelphia

2008-01-01T23:59:59.000Z

32

Electrochemical Isotope Effect and Lithium Isotope Separation  

Science Journals Connector (OSTI)

In a series of papers Kavner et al. (2005, 2008)(2, 3) derive an equation predicting isotopic fractionation due to an electrochemical isotope effect (?EIE), defined by the ratio of electron transfer rates (k?/k) for isotopically substituted species (prime for heavy isotopologues): where v, ?G, kB, T, m, ?eq, QP/QR, z, e, and ? denote collision frequency, activation free energy, Boltzmann’s constant, temperature, mass in motion, equilibrium fractionation factor, partition function ratio of abundant isotopologues of product (P) and reactant (R), number of electrons, charge of electron, and Marcus reorganization energy, respectively. ... fractional isotope evolution of Zn isotopes during an electroplating process which stepwise removes most of the Zn from the aq. ...

Jay R. Black; Grant Umeda; Bruce Dunn; William F. McDonough; Abby Kavner

2009-07-06T23:59:59.000Z

33

Assessment of Non-traditional Isotopic Ratios by Mass Spectrometry for Analysis of Nuclear Activities: Annual Report Year 2  

SciTech Connect (OSTI)

The objective of this work is to identify isotopic ratios suitable for analysis via mass spectrometry that distinguish between commercial nuclear reactor fuel cycles, fuel cycles for weapons grade plutonium, and products from nuclear weapons explosions. Methods will also be determined to distinguish the above from medical and industrial radionuclide sources. Mass spectrometry systems will be identified that are suitable for field measurement of such isotopes in an expedient manner. Significant progress has been made with this project within the past year: (1) Isotope production from commercial nuclear fuel cycles and nuclear weapons fuel cycles have been modeled with the ORIGEN and MCNPX codes. (2) MCNPX has been utilized to calculate isotopic inventories produced in a short burst fast bare sphere reactor (to approximate the signature of a nuclear weapon). (3) Isotopic ratios have been identified that are good for distinguishing between commercial and military fuel cycles as well as between nuclear weapons and commercial nuclear fuel cycles. (4) Mass spectrometry systems have been assessed for analysis of the fission products of interest. (5) A short-list of forensic ratios have been identified that are well suited for use in portable mass spectrometry systems.

Biegalski, S; Buchholz, B

2009-08-26T23:59:59.000Z

34

Isotope mass shift for two-electron atoms Petersburg Nuclear Physics Institute, Gatchina, 188300, Russia  

E-Print Network [OSTI]

, 188300, Russia (Dated: 29 April 2004) Accurate calculations of the isotope shift for atomic transitions

Kozlov, Mikhail G

35

Isotope mass shift for two-electron atoms II Petersburg Nuclear Physics Institute, Gatchina, 188300, Russia  

E-Print Network [OSTI]

, Gatchina, 188300, Russia (Dated: 31 October 2006) Accurate calculations of the isotope shift for atomic

Kozlov, Mikhail G

36

Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability  

SciTech Connect (OSTI)

Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure relative uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process to provide a distinction between uranium atoms and potential isobars without the aid of chemical purification and separation. We explore the laser parameters critical to the ionization process and their effects on the measured isotope ratio. Specifically, the use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of {sup 235}U/{sup 238}U ratios to decrease laser-induced isotopic fractionation. By broadening the bandwidth of the first laser in a 3-color, 3-photon ionization process from a bandwidth of 1.8 GHz to about 10 GHz, the variation in sequential relative isotope abundance measurements decreased from >10% to less than 0.5%. This procedure was demonstrated for the direct interrogation of uranium oxide targets with essentially no sample preparation. A rate equation model for predicting the relative ionization probability has been developed to study the effect of variation in laser parameters on the measured isotope ratio. This work demonstrates that RIMS can be used for the robust measurement of uranium isotope ratios.

Isselhardt, B H

2011-09-06T23:59:59.000Z

37

Analyzing Nuclear Fuel Cycles from Isotopic Ratios of Waste Products Applicable to Measurement by Accelerator Mass Spectrometry  

SciTech Connect (OSTI)

An extensive study was conducted to determine isotopic ratios of nuclides in spent fuel that may be utilized to reveal historical characteristics of a nuclear reactor cycle. This forensic information is important to determine the origin of unknown nuclear waste. The distribution of isotopes in waste products provides information about a nuclear fuel cycle, even when the isotopes of uranium and plutonium are removed through chemical processing. Several different reactor cycles of the PWR, BWR, CANDU, and LMFBR were simulated for this work with the ORIGEN-ARP and ORIGEN 2.2 codes. The spent fuel nuclide concentrations of these reactors were analyzed to find the most informative isotopic ratios indicative of irradiation cycle length and reactor design. Special focus was given to long-lived and stable fission products that would be present many years after their creation. For such nuclides, mass spectrometry analysis methods often have better detection limits than classic gamma-ray spectroscopy. The isotopic ratios {sup 151}Sm/{sup 146}Sm, {sup 149}Sm/{sup 146}Sm, and {sup 244}Cm/{sup 246}Cm were found to be good indicators of fuel cycle length and are well suited for analysis by accelerator mass spectroscopy.

Biegalski, S R; Whitney, S M; Buchholz, B

2005-08-24T23:59:59.000Z

38

Wave?number solution for a string with distributed mass properties  

Science Journals Connector (OSTI)

A structure with spatially variable properties when excited at a single frequency will excite many wave numbers. In this paper the vibration of a string with a mass distribution m(x) given by a Fourier series expansion is analyzed. The equation governing the wave?number solution w(k) for the string displacement is obtained via Fourier transform. The final result is a finite?difference equation. The finite?difference equation relates all of the displacement wave numbers to each other. The solution to this equation is obtained by rewriting it as a system of simultaneous equations that are then solved by standard linear algebra techniques. Wave?number spectral solutions are obtained for different mass distribution. In one case the mass distribution is assumed to vary in a discontinuous manner between adjacent bays in another case the mass is assumed to vary in a ‘‘triangular’’ manner. The wave?number solutions are presented in 3?D graphs so that the magnitude of the displacement can be seen as a function of the wave number and either the magnitude of the additional mass the area over which the mass is distributed or the length of the bay. In the limiting case as the mass distribution becomes very concentrated the classical pass/stop band familiar with periodic structures is recovered. ?

Mauro Pierucci

1999-01-01T23:59:59.000Z

39

Precise ruthenium fission product isotopic analysis using dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS)  

SciTech Connect (OSTI)

99Tc is a subsurface contaminant of interest at numerous federal, industrial, and international facilities. However, as a mono-isotopic fission product, 99Tc lacks the ability to be used as a signature to differentiate between the different waste disposal pathways that could have contributed to subsurface contamination at these facilities. Ruthenium fission-product isotopes are attractive analogues for the characterization of 99Tc sources because of their direct similarity to technetium with regard to subsurface mobility, and their large fission yields and low natural background concentrations. We developed an inductively coupled plasma mass spectrometry (ICP-MS) method capable of measuring ruthenium isotopes in groundwater samples and extracts of vadose zone sediments. Samples were analyzed directly on a Perkin Elmer ELAN DRC II ICP-MS after a single pass through a 1-ml bed volume of Dowex AG 50W-X8 100-200 mesh cation exchange resin. Precise ruthenium isotopic ratio measurements were achieved using a low-flow Meinhard-type nebulizer and long sample acquisition times (150,000 ms). Relative standard deviations of triplicate replicates were maintained at less than 0.5% when the total ruthenium solution concentration was 0.1 ng/ml or higher. Further work was performed to minimize the impact caused by mass interferences using the dynamic reaction cell (DRC) with O2 as the reaction gas. The aqueous concentrations of 96Mo and 96Zr were reduced by more than 99.7% in the reaction cell prior to injection of the sample into the mass analyzer quadrupole. The DRC was used in combination with stable-mass correction to quantitatively analyze samples containing up to 2-orders of magnitude more zirconium and molybdenum than ruthenium. The analytical approach documented herein provides an efficient and cost-effective way to precisely measure ruthenium isotopes and quantitate total ruthenium (natural vs. fission-product) in aqueous matrixes.

Brown, Christopher F.; Dresel, P. Evan; Geiszler, Keith N.; Farmer, Orville T.

2006-05-09T23:59:59.000Z

40

Standard test method for isotopic analysis of uranium hexafluoride by double standard single-collector gas mass spectrometer method  

E-Print Network [OSTI]

1.1 This is a quantitative test method applicable to determining the mass percent of uranium isotopes in uranium hexafluoride (UF6) samples with 235U concentrations between 0.1 and 5.0 mass %. 1.2 This test method may be applicable for the entire range of 235U concentrations for which adequate standards are available. 1.3 This test method is for analysis by a gas magnetic sector mass spectrometer with a single collector using interpolation to determine the isotopic concentration of an unknown sample between two characterized UF6 standards. 1.4 This test method is to replace the existing test method currently published in Test Methods C761 and is used in the nuclear fuel cycle for UF6 isotopic analyses. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 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 appro...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Standard test method for isotopic analysis of hydrolyzed uranium hexafluoride and uranyl nitrate solutions by thermal ionization mass spectrometry  

E-Print Network [OSTI]

1.1 This method applies to the determination of isotopic composition in hydrolyzed nuclear grade uranium hexafluoride. It covers isotopic abundance of 235U between 0.1 and 5.0 % mass fraction, abundance of 234U between 0.0055 and 0.05 % mass fraction, and abundance of 236U between 0.0003 and 0.5 % mass fraction. This test method may be applicable to other isotopic abundance providing that corresponding standards are available. 1.2 This test method can apply to uranyl nitrate solutions. This can be achieved either by transforming the uranyl nitrate solution to a uranyl fluoride solution prior to the deposition on the filaments or directly by depositing the uranyl nitrate solution on the filaments. In the latter case, a calibration with uranyl nitrate standards must be performed. 1.3 This test method can also apply to other nuclear grade matrices (for example, uranium oxides) by providing a chemical transformation to uranyl fluoride or uranyl nitrate solution. 1.4 This standard does not purport to address al...

American Society for Testing and Materials. Philadelphia

2005-01-01T23:59:59.000Z

42

Determination of ultratrace boron concentrations in uranium oxide by isotope dilution-thermal ionization mass spectrometry using a simplified separation procedure  

Science Journals Connector (OSTI)

Exhaustive reviews on analytical methodologies and mass spectrometric instrumentation for the determination of boron in different matrices such as biological tissues,...1, 4, 5]. It is an established fact that Isotope

Radhika M. Rao; Ankush R. Parab; K. Sasi Bhushan; Suresh K. Aggarwal

2010-06-01T23:59:59.000Z

43

Theoretical study of odd-mass Fr isotopes using the collective clusterization approach of the dynamical cluster-decay model  

Science Journals Connector (OSTI)

The reaction dynamics of various odd-mass Fr isotopes is studied over a wide range of incident energies, spread across the Coulomb barrier. The specific reactions analyzed are 18O+197Au and 19F+192,194,196,198,200Pt, forming odd-mass 211?219Fr* compound systems where some data are available for three of these isotopes: 213,215,217Fr*. Based on the dynamical cluster-decay model (DCM), we have extended our calculations of the evaporation residue (ER) cross sections to the mainly fissioning 215Fr*, using the systematics of 213,217Fr* isotopes where the available ER cross sections (as well as fusion-fission cross sections) were studied earlier within the DCM. In order to obtain a clear picture of the dynamics involved, including entrance channel effects, the variations of fragmentation potential, preformation factor, and decay barrier height are analyzed. The relevance of barrier modification effects is also explored in the decay of 213,215,217Fr* nuclei. In addition, fusion-fission (ff) cross sections are extended to 213,217Fr* systems where some more data has recently become available. Also, the fission fragment anisotropies (so far measured and studied for 215Fr* alone) are estimated for 213,217Fr* using DCM for the use of nonsticking moment of inertia, and relevant comparison with the sticking moment-of-inertia approach is analyzed. Furthermore, the shell closure effects of the decay fragments are investigated for odd-mass 211?219Fr* isotopes.

Gudveen Sawhney; Gurvinder Kaur; Manoj K. Sharma; Raj K. Gupta

2013-09-09T23:59:59.000Z

44

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

45

DETERMINATION OF 237NP AND PU ISOTOPES IN LARGE SOIL SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY  

SciTech Connect (OSTI)

A new method for the determination of {sup 237}Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of {sup 237}Np and Pu isotopes by ICP-MS. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via {sup 238}U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1 x 10{sup 6}. Alpha spectrometry can also be applied so that the shorter-lived {sup 238}Pu isotope can be measured successfully. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu and {sup 238}Pu were measured by alpha spectrometry.

Maxwell, S.

2010-07-26T23:59:59.000Z

46

unstable isotope  

Science Journals Connector (OSTI)

unstable isotope, radioisotope ? unstabiles Isotop n, nichtstabiles Isotop, radioaktives Isotop, Radioisotop

2014-08-01T23:59:59.000Z

47

Global energy gradients and size in colonial organisms: Worker mass and worker number  

E-Print Network [OSTI]

Global energy gradients and size in colonial organisms: Worker mass and worker number in ant size varies globally is a key challenge to ecology. Solar energy may shape gradients of body size by its effects on local temperature and net primary productivity (16­20). Rising global temperatures (21

Kaspari, Mike

48

Expressions for the number of J=0 pairs in even-even Ti isotopes  

E-Print Network [OSTI]

We count the number of pairs in the single j-shell model of {44}Ti for various interactions. For a state of total angular momentum I, the wave function can be written in terms of the probability amplitude D(Jp Jn) that the protons couple to Jp and the neutrons to Jn. For I=0 there are three states with (I=0,T=0) and one with (I=0,T=2). The latter is the double analog of {44}Ca. In that case (T=2), the magnitude of D(JJ) is the same as that of a corresponding two-particle fractional parentage coefficient. In counting the number of pairs with an even angular momentum J, we find a new relationship obtained by diagonalizing a unitary nine-j symbol. We are also able to get results for the `no-interaction' case for T=0 states, for which it is found, e.g., that there are less (J=1,T=0) pairs than on the average. Relative to this `no-interaction case', we find for the most realistic interaction used that there is an enhancement of pairs with angular momentum J=0,2,1 and 7, and a depletion for the others. Also considered are interactions in which only the (J=0,T=1) pair state is at lower energy, only the (J=1,T=0) pair state is lowered and where both are equally lowered, as well as the QQ interaction. We are also able to obtain simplified formulae for the number of J=0 pairs for the I=0 states in {46}Ti and {48}Ti by noting that the unique state with isospin |Tz|+2 is orthogonal to all the states with isospin |Tz|.

L. Zamick; A. Escuderos; S. J. Lee; A. Z. Mekjian; E. Moya de Guerra; A. A. Raduta; P. Sarriguren

2005-01-26T23:59:59.000Z

49

Intramolecular Isotope Effects for the Study of Reactions with MassTransfer Limitations  

E-Print Network [OSTI]

Page Figure 1 The origin of the kinetic isotope effect.............................................. 15 Figure 2 The solvent cage complexes of substrate and radical in intermolecular case............................................................................... 16 Figure 3 The solvent cage complex of substrate and radical in the intramolecular case ............................................................................ 17 Figure 4 Hydrogens to be used to calculate intermolecular KIE...

Wagner, Joshua G.

2010-01-16T23:59:59.000Z

50

Isotopic ratios and effective power determined by gamma-ray spectroscopy vs mass spectroscopy for molten salt extraction residues  

SciTech Connect (OSTI)

Impure plutonium metal is routinely processed by molten salt extraction (MSE) to reduce the amount of americium in the metal product. Throughput at various facilities where similar processes are performed has made it essential to evaluate uncertainties and possible discrepancies in the analyses of these difficult MSE materials. In an effort to evaluate the plutonium isotopic ratios and americium concentrations obtained from gamma-ray spectral data analyzed by the computer code GRPAUT, measurements were made on ten MSE salts as received and after pulverization and blending. These results were then compared to the specific powers obtained from isotopic ratios determined by mass spectrometry on these same ten samples. Americium values ranged from a few thousand parts-per-million of total plutonium to greater than 50,000 ppM. Our results indicate a small discrepancy between specific powers as determined by GRPAUT on as received'' vs pulverized and blended MSE salts. The specific powers obtained via GRPAUT on the pulverized salts agree somewhat better with specific powers obtained from the mass spectroscopy data. This work may indicate that a small discrepancy exists in the specific powers by using GRPAUT on heterogeneous, high americium samples. 5 refs., 6 tabs.

Longmire, V.L.; Cremers, T.L.; Sedlacek, W.A.; Long, S.M.; Scarborough, A.M.; Hurd, J.R.

1990-01-01T23:59:59.000Z

51

RAPID DETERMINATION OF 237 NP AND PU ISOTOPES IN WATER BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY  

SciTech Connect (OSTI)

A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes can be measured successfully. The method allows for simultaneous extraction of 20 samples (including QC samples) in 4 to 6 hours, and can also be used for emergency response. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu, {sup 238}Pu, and {sup 239}Pu were measured by alpha spectrometry.

Maxwell, S.; Jones, V.; Culligan, B.; Nichols, S.; Noyes, G.

2010-06-23T23:59:59.000Z

52

Constraints on the dark matter particle mass from the number of Milky Way satellites  

SciTech Connect (OSTI)

We have conducted N-body simulations of the growth of Milky Way-sized halos in cold and warm dark matter cosmologies. The number of dark matter satellites in our simulated Milky Ways decreases with decreasing mass of the dark matter particle. Assuming that the number of dark matter satellites exceeds or equals the number of observed satellites of the Milky Way, we derive lower limits on the dark matter particle mass. We find with 95% confidence m{sub s}>13.3 keV for a sterile neutrino produced by the Dodelson and Widrow mechanism, m{sub s}>8.9 keV for the Shi and Fuller mechanism, m{sub s}>3.0 keV for the Higgs decay mechanism, and m{sub WDM}>2.3 keV for a thermal dark matter particle. The recent discovery of many new dark matter dominated satellites of the Milky Way in the Sloan Digital Sky Survey allows us to set lower limits comparable to constraints from the complementary methods of Lyman-{alpha} forest modeling and x-ray observations of the unresolved cosmic x-ray background and of dark matter halos from dwarf galaxy to cluster scales. Future surveys like LSST, DES, PanSTARRS, and SkyMapper have the potential to discover many more satellites and further improve constraints on the dark matter particle mass.

Polisensky, Emil [Naval Research Laboratory, Washington, D.C. 20375 (United States); Department of Astronomy, University of Maryland, College Park, Maryland 20745 (United States); Ricotti, Massimo [Department of Astronomy, University of Maryland, College Park, Maryland 20745 (United States)

2011-02-15T23:59:59.000Z

53

Isotope Effect of Mercury Diffusion in Air  

Science Journals Connector (OSTI)

Isotope fractionation describes the separation of a reservoir with one isotope composition into “fractions” with different isotope compositions due to small isotopic differences in equilibrium partitioning, rates of mass transfer, or rates of transformation. ... (29) ?202Hg is the value most frequently used to examine mass dependent fractionation of mercury isotopes as 202Hg is the heaviest mercury isotope without significant isobaric interferences. ...

Paul G. Koster van Groos; Bradley K. Esser; Ross W. Williams; James R. Hunt

2013-12-23T23:59:59.000Z

54

Measurement of positional isotope exchange rates in enzyme catalyzed reactions by fast atom bombardment mass spectrometry  

E-Print Network [OSTI]

OF FIGURES Page Figure 1. Fast atom bombardment mass spectra of ANP from acetyl CoA synthetase PIX reactions 25 Figure 2. Fast atom bombardment mass spectra of ATP rath 18 various amounts of 0 Figure 3. Fast atom bombardment mass spectra of ANP from... of this phosphate was the result of P-y bridge to 0-non- bridge PK within the labelled ATP molecule. Through reaction rath diazcmcthane the inorganic phosphate was converted to methyl phosphate. Finally this volatile derivative was analyzed mth gas...

Hilscher, Larry Wayne

2012-06-07T23:59:59.000Z

55

Laser Ablation Inductively Coupled Plasma Mass Spectrometry Measurement of Isotope Ratios in Depleted Uranium Contaminated Soils  

Science Journals Connector (OSTI)

Laser ablation of pressed soil pellets was examined as a means of direct sample introduction to enable inductively coupled plasma mass spectrometry (ICP-MS) screening of soils for...

Seltzer, Michael D

2003-01-01T23:59:59.000Z

56

It's Elemental - Isotopes of the Element Magnesium  

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

Sodium Sodium Previous Element (Sodium) The Periodic Table of Elements Next Element (Aluminum) Aluminum Isotopes of the Element Magnesium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 24 78.99% STABLE 25 10.00% STABLE 26 11.01% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 19 4.0 picoseconds Double Proton Emission 100.00% 20 90.8 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission ~ 27.00% 21 122 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 32.60% Electron Capture with delayed Alpha Decay < 0.50%

57

It's Elemental - Isotopes of the Element Chlorine  

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

Sulfur Sulfur Previous Element (Sulfur) The Periodic Table of Elements Next Element (Argon) Argon Isotopes of the Element Chlorine [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 35 75.76% STABLE 37 24.24% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 28 No Data Available Proton Emission (suspected) No Data Available 29 < 20 nanoseconds Proton Emission No Data Available 30 < 30 nanoseconds Proton Emission No Data Available 31 150 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 0.70% 32 298 milliseconds Electron Capture 100.00%

58

It's Elemental - Isotopes of the Element Potassium  

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

Argon Argon Previous Element (Argon) The Periodic Table of Elements Next Element (Calcium) Calcium Isotopes of the Element Potassium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 39 93.2581% STABLE 40 0.0117% 1.248×10+9 years 41 6.7302% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 32 No Data Available Proton Emission (suspected) No Data Available 33 < 25 nanoseconds Proton Emission No Data Available 34 < 25 nanoseconds Proton Emission No Data Available 35 178 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 0.37% 36 342 milliseconds Electron Capture 100.00%

59

It's Elemental - Isotopes of the Element Phosphorus  

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

Silicon Silicon Previous Element (Silicon) The Periodic Table of Elements Next Element (Sulfur) Sulfur Isotopes of the Element Phosphorus [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 31 100% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 24 No Data Available Electron Capture (suspected) No Data Available Proton Emission (suspected) No Data Available 25 < 30 nanoseconds Proton Emission 100.00% 26 43.7 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission No Data Available 27 260 milliseconds Electron Capture 100.00% Electron Capture with

60

It's Elemental - Isotopes of the Element Oxygen  

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

Nitrogen Nitrogen Previous Element (Nitrogen) The Periodic Table of Elements Next Element (Fluorine) Fluorine Isotopes of the Element Oxygen [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 16 99.757% STABLE 17 0.038% STABLE 18 0.205% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 12 1.139×10-21 seconds Proton Emission No Data Available 13 8.58 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 100.00% 14 70.620 seconds Electron Capture 100.00% 15 122.24 seconds Electron Capture 100.00% 16 STABLE - - 17 STABLE - - 18 STABLE - - 19 26.88 seconds Beta-minus Decay 100.00%

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

It's Elemental - Isotopes of the Element Gallium  

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

Zinc Zinc Previous Element (Zinc) The Periodic Table of Elements Next Element (Germanium) Germanium Isotopes of the Element Gallium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 69 60.108% STABLE 71 39.892% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 56 No Data Available Proton Emission (suspected) No Data Available 57 No Data Available Proton Emission (suspected) No Data Available 58 No Data Available Proton Emission (suspected) No Data Available 59 No Data Available Proton Emission (suspected) No Data Available 60 70 milliseconds Electron Capture 98.40%

62

It's Elemental - Isotopes of the Element Sodium  

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

Neon Neon Previous Element (Neon) The Periodic Table of Elements Next Element (Magnesium) Magnesium Isotopes of the Element Sodium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 23 100% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 18 1.3×10-21 seconds Proton Emission 100.00% 19 < 40 nanoseconds Proton Emission No Data Available 20 447.9 milliseconds Electron Capture with delayed Alpha Decay 20.05% Electron Capture 100.00% 21 22.49 seconds Electron Capture 100.00% 22 2.6027 years Electron Capture 100.00% 23 STABLE - - 24 14.997 hours Beta-minus Decay 100.00%

63

It's Elemental - Isotopes of the Element Neon  

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

Fluorine Fluorine Previous Element (Fluorine) The Periodic Table of Elements Next Element (Sodium) Sodium Isotopes of the Element Neon [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 20 90.48% STABLE 21 0.27% STABLE 22 9.25% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 16 9×10-21 seconds Double Proton Emission 100.00% 17 109.2 milliseconds Electron Capture with delayed Alpha Decay No Data Available Electron Capture 100.00% Electron Capture with delayed Proton Emission 100.00% 18 1.6670 seconds Electron Capture 100.00% 19 17.22 seconds Electron Capture 100.00% 20 STABLE - -

64

It's Elemental - Isotopes of the Element Copper  

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

Nickel Nickel Previous Element (Nickel) The Periodic Table of Elements Next Element (Zinc) Zinc Isotopes of the Element Copper [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 63 69.15% STABLE 65 30.85% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 52 No Data Available Proton Emission No Data Available 53 < 300 nanoseconds Electron Capture No Data Available Proton Emission No Data Available 54 < 75 nanoseconds Proton Emission No Data Available 55 27 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 15.0% 56 93 milliseconds Electron Capture 100.00%

65

It's Elemental - Isotopes of the Element Boron  

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

Beryllium Beryllium Previous Element (Beryllium) The Periodic Table of Elements Next Element (Carbon) Carbon Isotopes of the Element Boron [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 10 19.9% STABLE 11 80.1% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 6 No Data Available Double Proton Emission (suspected) No Data Available 7 3.255×10-22 seconds Proton Emission No Data Available Alpha Decay No Data Available 8 770 milliseconds Electron Capture 100.00% Electron Capture with delayed Alpha Decay 100.00% 9 8.439×10-19 seconds Proton Emission 100.00% Double Alpha Decay 100.00%

66

It's Elemental - Isotopes of the Element Tungsten  

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

Tantalum Tantalum Previous Element (Tantalum) The Periodic Table of Elements Next Element (Rhenium) Rhenium Isotopes of the Element Tungsten [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 180 0.12% >= 6.6×10+17 years 182 26.50% STABLE 183 14.31% > 1.3×10+19 years 184 30.64% STABLE 186 28.43% > 2.3×10+19 years Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 157 275 milliseconds Electron Capture No Data Available 158 1.25 milliseconds Alpha Decay 100.00% 158m 0.143 milliseconds Isomeric Transition No Data Available Alpha Decay No Data Available 159 7.3 milliseconds Alpha Decay ~ 99.90%

67

It's Elemental - Isotopes of the Element Carbon  

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

Boron Boron Previous Element (Boron) The Periodic Table of Elements Next Element (Nitrogen) Nitrogen Isotopes of the Element Carbon [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 12 98.93% STABLE 13 1.07% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 8 1.981×10-21 seconds Proton Emission 100.00% Alpha Decay No Data Available 9 126.5 milliseconds Electron Capture 100.00% Electron Capture with delayed Proton Emission 61.60% Electron Capture with delayed Alpha Decay 38.40% 10 19.308 seconds Electron Capture 100.00% 11 20.334 minutes Electron Capture 100.00% 12 STABLE - -

68

It's Elemental - Isotopes of the Element Rhenium  

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

Tungsten Tungsten Previous Element (Tungsten) The Periodic Table of Elements Next Element (Osmium) Osmium Isotopes of the Element Rhenium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 185 37.40% STABLE 187 62.60% 4.33×10+10 years Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 159 No Data Available No Data Available No Data Available 160 0.82 milliseconds Proton Emission 91.00% Alpha Decay 9.00% 161 0.44 milliseconds Proton Emission 100.00% Alpha Decay <= 1.40% 161m 14.7 milliseconds Alpha Decay 93.00% Proton Emission 7.00% 162 107 milliseconds Alpha Decay 94.00% Electron Capture 6.00%

69

It's Elemental - Isotopes of the Element Francium  

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

Radon Radon Previous Element (Radon) The Periodic Table of Elements Next Element (Radium) Radium Isotopes of the Element Francium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Francium has no naturally occurring isotopes. Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 199 12 milliseconds Alpha Decay > 0.00% Electron Capture No Data Available 200 49 milliseconds Alpha Decay 100.00% 201 62 milliseconds Alpha Decay 100.00% 201m 19 milliseconds Alpha Decay 100.00% 202 0.30 seconds Alpha Decay 100.00% 202m 0.29 seconds Alpha Decay 100.00% 203 0.55 seconds Alpha Decay <= 100.00% 204 1.8 seconds Alpha Decay 92.00%

70

It's Elemental - Isotopes of the Element Radon  

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

Astatine Astatine Previous Element (Astatine) The Periodic Table of Elements Next Element (Francium) Francium Isotopes of the Element Radon [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Radon has no naturally occurring isotopes. Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 193 1.15 milliseconds Alpha Decay 100.00% 194 0.78 milliseconds Alpha Decay 100.00% 195 6 milliseconds Alpha Decay 100.00% 195m 5 milliseconds Alpha Decay 100.00% 196 4.4 milliseconds Alpha Decay 99.90% Electron Capture ~ 0.10% 197 53 milliseconds Alpha Decay 100.00% 197m 25 milliseconds Alpha Decay 100.00% 198 65 milliseconds Alpha Decay No Data Available

71

Perchlorate Isotope Forensics  

Science Journals Connector (OSTI)

In this study, comprehensive stable isotope analyses (37Cl/35Cl and 18O/17O/16O) of perchlorate from known synthetic and natural sources reveal systematic differences in isotopic characteristics that are related to the formation mechanisms. ... ?37Cl and ?18O are measures of mass-dependent fractionation of Cl and O isotopes by normal physical, chemical, or biological processes. ...

John Karl Böhlke; Neil C. Sturchio; Baohua Gu; Juske Horita; Gilbert M. Brown; W. Andrew Jackson; Jacimaria Batista; Paul B. Hatzinger

2005-11-04T23:59:59.000Z

72

Number  

Office of Legacy Management (LM)

' ' , /v-i 2 -i 3 -A, This dow'at consists ~f--~-_,_~~~p.~,::, Number -------of.-&--copies, 1 Series.,-a-,-. ! 1 THE UNIVERSITY OF ROCHESTER 1; r-.' L INTRAMURALCORRESPONDENCE i"ks' 3 2.. September 25, 1947 Memo.tor Dr. A. H, Dovdy . From: Dr. H. E, Stokinger Be: Trip Report - Mayvood Chemical Works A trip vas made Nednesday, August 24th vith Messrs. Robert W ilson and George Sprague to the Mayvood Chemical F!orks, Mayvood, New Jersey one of 2 plants in the U.S.A. engaged in the production of thorium compounds. The purpose of the trip vas to: l 1. Learn the type of chemical processes employed in the thorium industry (thorium nitrate). 2. Survey conditions of eeosure of personnel associated vith these chemical processes. 3. Obtain samples of atmospheric contaminants in the plant, as

73

Mass-Spectrometric Measurement of Lithium, Beryllium, and Boron Isotopes Produced in O16 by High-Energy Protons, and Some Astrophysical Implications  

Science Journals Connector (OSTI)

A special mass-spectrometric method has been developed to determine the isotopic ratios and isotopic absolute cross sections of Li, Be, and B, formed by spallation of oxygen irradiated by protons of energy 135, 550, and 19 GeV. A brief description is given of the ion source of the mass spectrometer—of an ion sputtering type—which permits a very efficient ionization of beryllium and boron. The performances are given; they allow the analysis of 10-12 to 10-13 g of these elements. The oxygen target is made of very high purity water, and special handling techniques have been worked out to reduce contamination to an acceptable level. The determination of each of the isotopic ratios Li7/Li6, Be9/Be7, Be10/Be9, and B11/B10 requires a specific method, which is described. Isotope dilution techniques are used to obtain the absolute cross sections; values in millibarns for 135-MeV protons are as follows: Li6:10±2, Li7:8.0±2.5, Be9:1.7±0.5, Be10:0.35±0.20, B10:11±3, and B11:25±8. There are no significant changes at the higher energies. The above cross sections give support to conclusions based previously on calculated values concerning the spallation origin of Li, Be, and B in the solar system, in stars, and in the cosmic radiation.

F. Yiou; M. Baril; J. Dufaure de Citres; P. Fontes; E. Gradsztajn; R. Bernas

1968-02-20T23:59:59.000Z

74

Determination of boron isotopic variations in aquatic systems with negative thermal ionization mass spectrometry as a tracer for anthropogenic influences  

Science Journals Connector (OSTI)

A technique for precise boron isotope ratio measurements with a high detection power ... –0.3% have been obtained for the determination of the 11B/10B isotope ratio using nanogram amounts of boron. Ba(OH)2 has be...

S. Eisenhut; K. G. Heumann; A. Vengosh

1996-03-01T23:59:59.000Z

75

Development of an on-line isotope dilution laser ablation inductively coupled plasma mass spectrometry (LA–ICP-MS) method for determination of boron in silicon wafers  

Science Journals Connector (OSTI)

A method has been developed based on an on-line isotope dilution technique couple with laser ablation/inductively coupled plasma mass spectrometry (LA–ICP-MS), for the determination of boron in p-type silicon wafers. The laser-ablated sample aerosol was mixed on-line with an enriched boron aerosol supplied continuously using a conventional nebulization system. Upon mixing the two aerosol streams, the isotope ratio of boron changed rapidly and was then recorded by the ICP-MS system for subsequent quantification based on the isotope dilution principle. As an on-line solid analysis method, this system accurately quantifies boron concentrations in silicon wafers without the need for an internal or external solid reference standard material. Using this on-line isotope dilution technique, the limit of detection for boron in silicon wafers is 2.8 × 1015 atoms cm?3. The analytical results obtained using this on-line methodology agree well with those obtained using wet chemical digestion methods for the analysis of p-type silicon wafers containing boron concentrations ranging from 1.0 × 1016 to 9.6 × 1018 atoms cm?3.

Chao-Kai Yang; Po-Hsiang Chi; Yong-Chine Lin; Yuh-Chang Sun; Mo-Hsiung Yang

2010-01-01T23:59:59.000Z

76

Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies  

SciTech Connect (OSTI)

The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.; Tian, G.; Rao, L.; Lukens, W.

2011-02-01T23:59:59.000Z

77

A World without Sample Preparation: Developing Rapid Uranium Isotope Measurement Capabilities by Resonance Ionization Mass Spectrometry (RIMS)  

SciTech Connect (OSTI)

We are developing highly sensitive, highly discriminating laser-based techniques for rapid determination of isotopic compositions. Rapid command of such information is critical to assessment of the origin and history of nuclear materials, particularly in post-detonation scenarios.

Knight, K B; Hutcheon, I D; Isselhardt, B H; Savina, M R; Prussin, S G

2009-06-08T23:59:59.000Z

78

The effect of particle resuspension during walking activity to PM10 mass and number concentrations in an indoor microenvironment  

Science Journals Connector (OSTI)

Abstract Mass and number concentration of particulate matter (PM10) was measured during walking experiments inside a laboratory. In total 20 walking experiments were conducted in a period of 3 months. Particle number concentration was measured in the size range of 0.02–1 ?m, while, mass concentration was measured in the range 0.1–10 ?m. The PM10 mass increased during the activity, by average 84%, whereas, the walking activity had no impact on particle number concentration. Human induced resuspension rates were examined under different dust loadings. The different dust loadings used (25, 15, 5, 1 g/m2) in order to evaluate the impact of surface loading on the indoor PM10 mass concentration and on the resuspension rate. Walking style was the same in all experiments. Moreover, the experiments involved two different walking patterns inside the laboratory (rectangular and line). The impact of different speed was also examined. The average resuspension rate was calculated to be equal to 10?2–10?3 hr?1. No impact on resuspension rate was observed for different walking patterns or walking speed. On the other hand, the measured mass concentration inside the room was increased when using higher dust loading on the floor, although the estimated resuspension rate found independent on the initially deposited surface dust loading.

Norbert Serfozo; Sofia Eirini Chatoutsidou; Mihalis Lazaridis

2014-01-01T23:59:59.000Z

79

Measurements of the mass and isotopic yields of the {sup 233}U(n{sub th},f) reaction at the Lohengrin spectrometer  

SciTech Connect (OSTI)

Over the last 10 years, a vast campaign of measurements has been initiated to improve the precision of neutron data for the involved key nuclei ({sup 232}Th, {sup 233}Pa and {sup 233}U) of the innovative Th -{sup 233}U cycle. This latter might indeed provide cleaner nuclear energy than the present U-Pu one. New measurements of charge and mass distributions of the fission products have been achieved at the Lohengrin spectrometer of the Inst. Laue-Langevin (ILL) during fall 2010 to complete the experimental data of {sup 233}U(n,f) that exist mainly for light fission fragments. That is why we performed measurements of mass and isotopic yields with a special focus on the heavy fission fragment part. Mass yields were measured by ion counting with an ionization chamber after separation by the Lohengrin spectrometer. Isotopic yields were derived from gamma spectrometry of mass-separated beams using HPGe clover detectors. This paper will present the results of these fission yield measurements along with details on the experimental set-up and the chosen analysis method. (authors)

Martin, F.; Sage, C.; Kessedjian, G. [LPSC, UJF Grenoble 1, CNRS/IN2P3, Grenoble (France); Bacri, C. O. [IPN, CNRS/IN2P3, Univ. Paris-Sud (France); Bidaud, A.; Billebaud, A.; Capellan, N.; Chabod, S. [LPSC, UJF Grenoble 1, CNRS/IN2P3, Grenoble (France); Cywinski, R. [Dept. Chemical and Biological Sciences, Univ. Ruddersfield (United Kingdom); Doligez, X. [IPN, CNRS/IN2P3, Univ. Paris-Sud (France); Faust, H.; Koester, U. [Institut Laue-Langevin, Grenoble (France); Letourneau, A.; Materna, T. [DSM/IRFU/SPhN, CEA Saclay (France); Mathieu, L. [CENBG, Universite de Bordeaux 1 (France); Meplan, O. [LPSC, UJF Grenoble 1, CNRS/IN2P3, Grenoble (France); Panebianco, S. [DSM/IRFU/SPhN, CEA Saclay (France); Serot, O. [DEN/DER/SPRC/LEPh, CEA Cadarache (France)

2011-07-01T23:59:59.000Z

80

The Number of Information Bits Related to the Minimum Quantum and Gravitational Masses in a Vacuum Dominated Universe  

E-Print Network [OSTI]

Wesson obtained a limit on quantum and gravitational mass in the universe by combining the cosmological constant Lambda, Planck constant, the speed of light c, and also the gravitational constant G. The corresponding masses are 2.0x10E-62 kg and 2.3E+54 kg respectively, and in general can be obtained with the help of a generic dimensional analysis, or from an analysis where the cosmological constant appears in a four dimensional space-time and as a result of a higher dimensional reduction. In this paper our goal is to establish a relation for both quantum and gravitational mass as function of the information number bit N. For this reason, we first derive an expression for the cosmological constant as a function of information bit, since both masses depend on it, and then various resulting relations are explored, in relation to information number of bits N. Fractional information bits imply no information extraction is possible. We see, that the order of magnitude of the various parameters as well as their ratios involve the large number 10E+122, that is produced naturally from the fundamental parameters of modern cosmology. Finally, we propose that in a complete quantum gravity theory the idea of information the might have to be included, with the quantum bits of information (q-bits) as one of its fundamental parameters, resulting thus to a more complete understanding of the universe, its laws, and its evolution.

Ioannis Haranas; Ioannis Gkigkitzis

2014-06-09T23:59:59.000Z

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81

Mass number dependence of the Skyrme-force-induced nuclear symmetry energy  

E-Print Network [OSTI]

The global mass dependence of the nuclear symmetry energy and its two basic ingredients due to the mean-level spacing and effective strength of the isovector mean-potential is studied within the Skyrme-Hartree-Fock model. In particular, our study determines the ratio of the surface-to-volume contributions to the nuclear symmetry energy to be ~1.6 and reveals that contributions due to mean-level spacing and effective strength of the isovector mean-potential are almost equal after removing momentum-dependent effects by rescaling them with isoscalar and isovector effective masses, respectively.

M. Rafalski; W. Satula; R. Wyss

2005-11-04T23:59:59.000Z

82

Dipole strength distributions in the stable Ba isotopes {sup 134-138}Ba: A study in the mass region of a nuclear shape transition  

SciTech Connect (OSTI)

The low-lying dipole strength distributions in the odd-mass isotopes {sup 135,137}Ba were studied in nuclear resonance fluorescence experiments (NRF) performed at the Stuttgart Dynamitron facility using bremsstrahlung beams with end point energies of 4.1, 3.1, and 2.5 MeV. Numerous excited states, most of them unknown so far, were observed in the excitation energy range up to 4 MeV. Detailed spectroscopic information has been obtained on excitation energies, decay widths, decay branching ratios, and transition probabilities. The results for {sup 137}Ba are compared with calculations in the framework of the Quasiparticle-Phonon Model. The new data for {sup 135,137}Ba complete the systematics of low-lying dipole excitations as observed for the even Ba isotopes {sup 134,136,138}Ba in previous NRF experiments in Stuttgart. The complete systematics within the Ba isotopic chain, exhibiting a nuclear shape transition, is discussed with respect to E1 two-phonon excitations, M1 scissors mode excitations, and in regard to the new critical point symmetries.

Scheck, M.; Garrel, H. von; Belic, D.; Kneissl, U.; Kohstall, C.; Nord, A.; Pitz, H.H.; Stedile, F. [Institut fuer Strahlenphysik, Universitaet Stuttgart, D-70569 Stuttgart (Germany); Tsoneva, N. [Institut fuer Theor. Physik, Universitaet Giessen, D-35392 Giessen (Germany); Brentano, P. von; Fransen, C.; Gade, A.; Jolie, J.; Linnemann, A.; Pietralla, N.; Werner, V. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Cologne (Germany); Stoyanov, C. [Institute for Nuclear Research and Nuclear Energy, 1784 Sofia (Bulgaria)

2004-10-01T23:59:59.000Z

83

The Planck Length Scale and Einstein Mass-Energy Obtained from the Sciama-Mach Large Number Relationship  

E-Print Network [OSTI]

If a physical significance should be attributed to the cosmological large number relationship obtained from Sciama's formulation of Mach's Principle, then a number of interesting physical conclusions may be drawn. The Planck length is naturally obtained as the amplitude of waves in a medium whose properties are implied by the relationship. The relativistic internal energy associated with a rest mass is explicitly related to the gravitational potential energy of the Universe, and consistency with the Einstein photon energy is demonstrated. Broader cosmological consequences of this formulation are addressed.

Scott Funkhouser

2003-09-25T23:59:59.000Z

84

Measurement of number, mass and size distribution of particles in the atmosphere  

Science Journals Connector (OSTI)

...size-fractionated manner using cascade impactors, which depend...mean free path of the gas molecules o er a signi...5, tra c-related gases, particle number and...and contracts with the Natural Environment Research Council...this period, exhaust gas emissions will be rich...

2000-01-01T23:59:59.000Z

85

Solid-state Marx based two-switch voltage modulator for the On-Line Isotope Mass Separator accelerator at the European Organization for Nuclear Research  

SciTech Connect (OSTI)

A new circuit topology is proposed to replace the actual pulse transformer and thyratron based resonant modulator that supplies the 60 kV target potential for the ion acceleration of the On-Line Isotope Mass Separator accelerator, the stability of which is critical for the mass resolution downstream separator, at the European Organization for Nuclear Research. The improved modulator uses two solid-state switches working together, each one based on the Marx generator concept, operating as series and parallel switches, reducing the stress on the series stacked semiconductors, and also as auxiliary pulse generator in order to fulfill the target requirements. Preliminary results of a 10 kV prototype, using 1200 V insulated gate bipolar transistors and capacitors in the solid-state Marx circuits, ten stages each, with an electrical equivalent circuit of the target, are presented, demonstrating both the improved voltage stability and pulse flexibility potential wanted for this new modulator.

Redondo, L. M.; Canacsinh, H.; Ferrao, N.; Mendes, C. [Instituto Superior de Engenharia de Lisboa (ISEL), R. Conselheiro Emidio Navarro 1, Lisbon 1959-007 (Portugal); Nuclear Physics Center-Lisbon University (CFNUL), Av. Prof. Gama Pinto 2, Lisbon 1649-003 (Portugal); Silva, J. Fernando [Instituto Superior Tecnico (IST), Universidade Tecnica de Lisboa, Av. Rovisco Pais 1, Lisbon 1049-001 (Portugal); Center for Innovation in Electrical and Energy Engineering-TU Lisbon, Av. Rovisco Pais 1, Lisbon 1049-001 (Portugal); Soares, R. [Nuclear Physics Center--Lisbon University (CFNUL), Av. Prof. Gama Pinto 2, Lisbon 1649-003 (Portugal); ABT Group, TE Department, Site de Prevessin, FR-01631 CERN (Switzerland); Schipper, J.; Fowler, A. [ABT Group, TE Department, Site de Prevessin, FR-01631 CERN (Switzerland)

2010-07-15T23:59:59.000Z

86

Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry  

E-Print Network [OSTI]

1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

American Society for Testing and Materials. Philadelphia

2000-01-01T23:59:59.000Z

87

Standard Test Method for Isotopic Analysis of Uranium Hexafluoride by Single-Standard Gas Source Multiple Collector Mass Spectrometer Method  

E-Print Network [OSTI]

1.1 This test method is applicable to the isotopic analysis of uranium hexafluoride (UF6) with 235U concentrations less than or equal to 5 % and 234U, 236U concentrations of 0.0002 to 0.1 %. 1.2 This test method may be applicable to the analysis of the entire range of 235U isotopic compositions providing that adequate Certified Reference Materials (CRMs or traceable standards) are available. 1.3 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 appropriate safety health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

88

Magnetic Isotope Effect in the Photolysis of Organotin Compounds  

Science Journals Connector (OSTI)

Fractionation of isotopes in chemical and biochemical reactions is induced by two isotope effects; their origin and physical nature are shown in Figure 1. ... The classical isotope effect (CIE) sorts isotopic nuclei on their masses; the magnetic isotope effect (MIE) demonstrates nuclear spin selectivity of reactions and separates isotopic nuclei according to their magnetic moments.1 ...

Anatoly L. Buchachenko; Vladimir L. Ivanov; Vitaly A. Roznyatovsky; Yuri A. Ustynyuk

2006-03-02T23:59:59.000Z

89

Deformation effects and neutrinoless positron ?? decay of Ru96, Pd102, Cd106, Xe124, Ba130, and Dy156 isotopes within a mechanism involving Majorana neutrino mass  

Science Journals Connector (OSTI)

The (?+?+)0? and (??+)0? modes of Ru96, Pd102, Cd106, Xe124, Ba130, and Dy156 isotopes are studied in the projected Hartree-Fock-Bogoliubov framework for the 0+?0+ transition. The reliability of the intrinsic wave functions required to study these decay modes has been established in our earlier works by obtaining an overall agreement between the theoretically calculated spectroscopic properties, namely yrast spectra, reduced B(E2:0+?2+) transition probabilities, quadrupole moments Q(2+) and gyromagnetic factors g(2+), and the available experimental data in the parent and daughter even-even nuclei. In the present work, the required nuclear transition matrix elements are calculated in the Majorana neutrino mass mechanism using the same set of intrinsic wave functions as used to study the two neutrino positron double-? decay modes. Limits on effective light neutrino mass ?m?? and effective heavy neutrino mass ?MN? are extracted from the observed limits on half-lives T1/20?(0+?0+) of (?+?+)0? and (??+)0? modes. We also investigate the effect of quadrupolar correlations vis-a-vis deformation on nuclear transition matrix elements (NTMEs) required to study the (?+?+)0? and (??+)0? modes.

P. K. Rath, R. Chandra, K. Chaturvedi, P. K. Raina, and J. G. Hirsch

2009-10-06T23:59:59.000Z

90

E-Print Network 3.0 - abundance isotopic Sample Search Results  

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

Search Sample search results for: abundance isotopic Page: << < 1 2 3 4 5 > >> 1 ISOTOPE FRACTIONATION Isotopes are atoms whose nuclei contain the same number of protons but...

91

It's Elemental - Isotopes of the Element Nitrogen  

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

Carbon Carbon Previous Element (Carbon) The Periodic Table of Elements Next Element (Oxygen) Oxygen Isotopes of the Element Nitrogen [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 14 99.636% STABLE 15 0.364% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 10 No Data Available Proton Emission 100.00% 11 5.49×10-22 seconds Proton Emission 100.00% 12 11.000 milliseconds Electron Capture 100.00% 13 9.965 minutes Electron Capture 100.00% 14 STABLE - - 15 STABLE - - 16 7.13 seconds Beta-minus Decay 100.00% Beta-minus Decay with delayed Alpha Decay 1.2×10-3 % 17 4.173 seconds Beta-minus Decay 100.00%

92

Isotope hydrology of catchment basins: lithogenic and cosmogenic isotopic systems  

SciTech Connect (OSTI)

A variety of physical processes affect solute concentrations within catchment waters. The isotopic compositions of the solutes can indicate which processes have determined the observed concentrations. These processes together constitute the physical history of the water. Many solutes in natural waters are derived from the interaction between the water and the rock and/or soil within the system - these are termed `lithogenic` solutes. The isotopic compositions of these solutes provide information regarding rock-water interactions. Many other solutes have their isotopic compositions determined both within and outside of the catchment - i.e., in addition to being derived from catchment rock and soil, they are solutes that are also transported into the catchment. Important members of this group include solutes that have isotopic compositions produced by atomic particle interactions with other nuclides. The source of the atomic particles can be cosmic radiation (producing `cosmogenic` nuclides in the atmosphere and land surface), anthropogenic nuclear reactions (producing `thermonuclear` nuclides), or radioactive and fission decay of naturally-occurring elements, principally {sup 238}U (producing `in-situ` lithogenic nuclides in the deep subsurface). Current language usage often combines all of the atomic particle-produced nuclides under the heading `cosmogenic nuclides`, and for simplicity we will often follow that usage here, although always indicating which variety is being discussed. This paper addresses the processes that affect the lithogenic and cosmogenic solute concentrations in catchment waters, and how the isotopic compositions of the solutes can be used in integrative ways to identify these processes, thereby revealing the physical history of the water within a catchment system. The concept of a `system` is important in catchment hydrology. A catchment is the smallest landscape unit that can both participate in all of the aspects of the hydrologic cycle and also be treated as a mostly closed system for mass balance considerations. It is the near closure of the system that permits well- constrained chemical mass balance calculations to be made. These calculations generally focus of lithogenic solutes, and therefore in our discussions of lithogenic nuclides in the paper, the concept of chemical mass balance in a nearly dosed system will play an important role. Examination of the isotopic compositions of solutes provides a better understanding of the variety of processes controlling mass balance. It is with this approach that we examined the variety of processes occurring within the catchment system, such as weathering and soil production, generation of stormflow and streamflow (hydrograph separation), movement of soil pore water, groundwater flow, and the overall processes involved with basinal water balance. In this paper, the term `nuclide` will be used when referring to a nuclear species that contains a particular number of protons and neutrons. The term is not specific to any element. The term `isotope` will be used to distinguish nuclear species of a given element (atoms with the same number of protons). That is to say, there are many nuclides in nature - for example, {sup 36}Cl, {sup 87}Sr, {sup 238}U; the element has four naturally-occurring isotopes - {sup 87}Sr, and {sup 88}Sr. This paper will first discuss the general principles that underlie the study of lithogenic and cosmogenic nuclides in hydrology, and provide references to some of the more important studies applying these principles and nuclides. We then turn in the second section to a discussion of their specific applications in catchment- scale systems. The final section of this paper discusses new directions in the application of lithogenic and cosmogenic nuclides to catchment hydrology, with some thoughts concerning possible applications that still remain unexplored.

Nimz, G. J., LLNL

1998-06-01T23:59:59.000Z

93

The global geochemical cycles of iron and calcium: using novel isotope systems to understand weathering, global mass budgets, natural reaction rates, and paleoclimate  

E-Print Network [OSTI]

. Traditional geochemical proxies utilize variations in the oxygen, carbon, and boron isotopic compositionThe global geochemical cycles of iron and calcium: using novel isotope systems to understand of California, Berkeley Spring 2005 #12;The global geochemical cycles of iron and calcium: using novel isotope

Fantle, Matthew

94

Production and Decay Properties of Protactinium Isotopes of Mass 222 to 225 Formed in Heavy-Ion Reactions  

Science Journals Connector (OSTI)

Four ?-decay chains initiated by Pa225, Pa224, Pa223, and Pa222 were produced by the bombardment of thallium, lead, and bismuth targets with beams of Ne22, Ne20, F19, O18, O16, N15, and N14 at the Berkeley heavy-ion linear accelerator. The reaction products were transported from the reaction cell by the helium-jet technique and their decay was measured with a semiconductor detector. Energy values, excitation functions, half-lives, and genetic relationships of individual peaks were determined. Two new techniques based on the use of a time-to-amplitude converter were developed for the measurement of ?sec half-lives of daughter products, and five half-lives in the ?sec range were measured.These new ? data help to determine the trends in ?-decay energies for isotopes of odd-Z elements, particularly in the poorly defined region just above the 126-neutron shell. This allows more accurate predictions of ?-decay properties of many unknown nuclei. Some anomalous behavior of the apparent ?-decay energies for nuclei with 133 and 135 neutrons is pointed out.

Jørn Borggreen; Kalevi Valli; Earl K. Hyde

1970-11-01T23:59:59.000Z

95

Isotopic Analysis- Fluid | Open Energy Information  

Open Energy Info (EERE)

Isotopic Analysis- Fluid Isotopic Analysis- Fluid Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Isotopic Analysis- Fluid Details Activities (61) Areas (32) Regions (6) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Fluid Lab Analysis Parent Exploration Technique: Fluid Lab Analysis Information Provided by Technique Lithology: Water rock interaction Stratigraphic/Structural: Hydrological: Origin of hydrothermal fluids; Mixing of hydrothermal fluids Thermal: Isotopic ratios can be used to characterize and locate subsurface thermal anomalies. Dictionary.png Isotopic Analysis- Fluid: Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in

96

Isotopic Analysis- Rock | Open Energy Information  

Open Energy Info (EERE)

Isotopic Analysis- Rock Isotopic Analysis- Rock Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Isotopic Analysis- Rock Details Activities (13) Areas (11) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Water rock interaction Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Isotopic Analysis- Rock: Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.

97

Isotopic tracer studies of oxygen transport through SiO2 films at 1000?°C using secondary ion mass spectrometry  

Science Journals Connector (OSTI)

Dry oxides (?8 ppm H2O) grown on Si(100) at 1000?°C at 1 atm using purified 1 6O2 and purified 1 8O2 were analyzed using secondary ion mass spectrometry.1 8O is observed at the interface in the bulk of the 1 6O oxide and at the surface in agreement with other recent reports. Our results show little lattice diffusion in agreement with Mikkelsen’s work [Appl. Phys. Lett. 4 5 1187 (1984)]. A previous report [J. Electrochem. Soc. 1 3 1 1944 (1984)] of appreciable lattice diffusion is due to higher water content.

C. J. Han; C. R. Helms

1986-01-01T23:59:59.000Z

98

paper-number : V11D-2318 abstract-number : 949668 Mass-conservative numerical scheme of bubble growth in incompressible viscous magmas  

E-Print Network [OSTI]

Pa(0) C : water concentration : surface tension i : Pa(0) M GT M : water molar mass G : gas constant scale decompression time scale = 2 RiPa(0) : dimensionless surface tension : porosity R S r P C(t,r) m is refined at the bubble boundary Scheme stability Constraint on the time step by physical considera- tion

d'Orléans, Université

99

Isotope Analysis  

Science Journals Connector (OSTI)

Naturally occurring oxygen includes three stable isotopes,16O,17O, and18O, with the relative abundances of 99.763%, 0.0375%, and 0.1995%, respectively. Isotopic analysis does not consider the absolute abundances ...

Tandong Yao; Wusheng Yu; Huabiao Zhao…

2014-08-01T23:59:59.000Z

100

Photo-oxidation of Water by Molecular Oxygen: Isotope Exchange and Isotope Effects  

Science Journals Connector (OSTI)

In order to detect the reaction, we used water highly enriched with isotopes 17O and 18O, controlling the isotope composition of molecular oxygen before and after reaction. ... stability of heavy-isotope clumps'; slower kinetics of reactions requiring the breakage of bonds between heavy isotopes; the mass dependence of diffusive and thermo-gravitational fractionations; mixing between components that differ from one another in bulk isotopic compn.; biochem. ... Study of oxygen three-isotope behavior during thermal decompn. of naturally occurring carbonates of calcium and magnesium in vacuo revealed that, surprisingly, anomalous isotopic compns. ...

Anatoly L. Buchachenko; Elena O. Dubinina

2011-03-30T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Definition: Isotopic Analysis- Fluid | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Isotopic Analysis- Fluid Jump to: navigation, search Dictionary.png Isotopic Analysis- Fluid Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable. Fluid isotopes are used to characterize a fluids origin, age, and/or interaction with rocks or other fluids based on unique isotopic ratios or concentrations.[1] View on Wikipedia Wikipedia Definition Isotope geochemistry is an aspect of geology based upon study of the relative and absolute concentrations of the elements and their isotopes in

102

A Gas Chromatography-Isotope Dilution High-Resolution Mass Spectrometry Method for Quantification of Isomeric Benzo[a]pyrene Diol Epoxide Hemoglobin Adducts in Humans  

Science Journals Connector (OSTI)

......Smoking blood We developed a gas chromatographyisotope...materials, industrial production of petroleum products...persist and accumulate A Gas ChromatographyIsotope...rate, accessible, and cost-effective foundation...have developed the first gas chromatographyisotope......

Angela D. Ragin; Kenroy E. Crawford; Alisha A. Etheredge; James Grainger; Donald G. Patterson; Jr.

2008-01-01T23:59:59.000Z

103

Carbon Isotopes  

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

Atmospheric Trace Gases » Carbon Isotopes Atmospheric Trace Gases » Carbon Isotopes Carbon Isotopes Gateway Pages to Isotopes Data Modern Records of Carbon and Oxygen Isotopes in Atmospheric Carbon Dioxide and Carbon-13 in Methane 800,000 Deuterium Record and Shorter Records of Various Isotopic Species from Ice Cores Carbon-13 13C in CO Measurements from Niwot Ridge, Colorado and Montana de Oro, California (Tyler) 13C in CO2 NOAA/CMDL Flask Network (White and Vaughn) CSIRO GASLAB Flask Network (Allison, Francey, and Krummel) CSIRO in situ measurements at Cape Grim, Tasmania (Francey and Allison) Scripps Institution of Oceanography (Keeling et al.) 13C in CH4 NOAA/CMDL Flask Network (Miller and White) Northern & Southern Hemisphere Sites (Quay and Stutsman) Northern & Southern Hemisphere Sites (Stevens)

104

Existence of long-lived isomeric states in naturally-occurring neutron-deficient Th isotopes  

SciTech Connect (OSTI)

Four long-lived neutron-deficient Th isotopes with atomic mass numbers 211 to 218 and abundances of (1-10)x10{sup -11} relative to {sup 232}Th have been found in a study of naturally-occurring Th using inductively coupled plasma-sector field mass spectrometry. It is deduced that long-lived isomeric states exist in these isotopes. The hypothesis that they might belong to a new class of long-lived high spin super- and hyperdeformed isomeric states is discussed.

Marinov, A.; Kashiv, Y. [Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Rodushkin, I. [Analytica AB, Aurorum 10, S-977 75 Luleaa (Sweden); Halicz, L.; Segal, I. [Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem 95501 (Israel); Pape, A. [IPHC-UMR7178, IN2P3-CNRS/ULP, BP 28, F-67037 Strasbourg cedex 2 (France); Gentry, R. V. [Earth Science Associates, P.O. Box 12067, Knoxville, Tennessee 37912-0067 (United States); Miller, H. W. [P. O. Box 1092, Boulder, Colorado 80306-1092 (United States); Kolb, D. [Department of Physics, University GH Kassel, D-34109 Kassel (Germany); Brandt, R. [Kernchemie, Philipps University, D-35041 Marburg (Germany)

2007-08-15T23:59:59.000Z

105

Final Report "Structure of Rare Isotopes"  

SciTech Connect (OSTI)

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.

Papenbrock, Thomas

2012-05-09T23:59:59.000Z

106

E-Print Network 3.0 - argon isotopes Sample Search Results  

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

one of the earliest isotope... this is not always the case--see later). The naturally occurring isotopes of argon are measured by mass spectrometry... isotopes but also small...

107

E-Print Network 3.0 - argon isotopic chains Sample Search Results  

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

one of the earliest isotope... this is not always the case--see later). The naturally occurring isotopes of argon are measured by mass spectrometry... isotopes but also small...

108

Magnesium-Isotope Fractionation During Plant Growth  

Science Journals Connector (OSTI)

With three stable isotopes naturally abundant (24Mg, 78.992%; 25Mg, 10.003%; 26Mg, 11.005%), magnesium stable isotope fractionation may provide insights into these cycles. ... Measurements of the magnesium isotopic composition of chlorophylls, seeds, shoots, roots, leaves, exudates, and the limiting nutrient solution over time show that the plant appears to establish an isotopic equilibrium with the nutrient available to it and that the plant (in particular, the seeds and exudates) becomes enriched in the heavy isotopes of magnesium in a mass-dependent relationship as the plant reaches maturity. ...

Jay R. Black; Emanuel Epstein; William D. Rains; Qing-zhu Yin; William H. Casey

2008-10-01T23:59:59.000Z

109

Slow Neutron Scattering by the Titanium Isotopes  

Science Journals Connector (OSTI)

Neutron diffraction studies are reported on isotopically enriched samples of TiO2 from which are evaluated the coherent scattering amplitudes of the titanium isotopes. Scattering amplitudes of +0.48, +0.33, -0.58, +0.08, and +0.55×10-12 cm were established for the titanium isotopes of mass 46, 47, 48, 49, and 50, respectively. The major isotope Ti48 is thus responsible for the anomalous scattering amplitude, -0.34×10-12 cm, characteristic of the normal element. Pronounced nuclear scattering resonance effects on the observed neutron scattering are suggested to occur for most of the isotopes.

C. G. Shull; M. K. Wilkinson; M. H. Mueller

1960-05-01T23:59:59.000Z

110

The New Element Californium (Atomic Number 98)  

DOE R&D Accomplishments [OSTI]

Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with about 35-Mev helium ions in the Berkeley Crocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and is thought to have the mass number 244. The observed mode of decay of 98{sup 244} is through the emission of alpha-particles, with energy of about 7.1 Mev, which agrees with predictions. Other considerations involving the systematics of radioactivity in this region indicate that it should also be unstable toward decay by electron capture. The chemical separation and identification of the new element was accomplished through the use of ion exchange adsorption methods employing the resin Dowex-50. The element 98 isotope appears in the eka-dysprosium position on elution curves containing berkelium and curium as reference points--that is, it precedes berkelium and curium off the column in like manner that dysprosium precedes terbium and gadolinium. The experiments so far have revealed only the tripositive oxidation state of eka-dysprosium character and suggest either that higher oxidation states are not stable in aqueous solutions or that the rates of oxidation are slow. The successful identification of so small an amount of an isotope of element 98 was possible only through having made accurate predictions of the chemical and radioactive properties.

Seaborg, G. T.; Thompson, S. G.; Street, K. Jr.; Ghiroso, A.

1950-06-19T23:59:59.000Z

111

Ultra-low Q values for neutrino mass measurements  

SciTech Connect (OSTI)

We investigate weak nuclear decays with extremely small kinetic energy release (Q value) and thus extremely good sensitivity to the absolute neutrino mass scale. In particular, we consider decays into excited daughter states, and we show that partial ionization of the parent atom can help to tune Q values to << 1 keV. We discuss several candidate isotopes undergoing {beta}{sup {+-}}, bound state {beta}, or electron capture decay, and come to the conclusion that a neutrino mass measurement using low-Q decays might only be feasible if no ionization is required, and if future improvements in isotope production technology, nuclear mass spectroscopy, and atomic structure calculations are possible. Experiments using ions, however, are extremely challenging due to the large number of ions that must be stored. New precision data on nuclear excitation levels could help to identify further isotopes with low-Q decay modes and possibly less challenging requirements.

Kopp, Joachim; /Heidelberg, Max Planck Inst. /Fermilab; Merle, Alexander; /Heidelberg, Max Planck Inst.

2009-11-01T23:59:59.000Z

112

Definition: Isotopic Analysis- Rock | Open Energy Information  

Open Energy Info (EERE)

Isotopic Analysis- Rock Isotopic Analysis- Rock Jump to: navigation, search Dictionary.png Isotopic Analysis- Rock Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.[1] View on Wikipedia Wikipedia Definition References ↑ http://wwwrcamnl.wr.usgs.gov/isoig/isopubs/itchch2.html Ret LikeLike UnlikeLike You like this.Sign Up to see what your friends like. rieved from "http://en.openei.org/w/index.php?title=Definition:Isotopic_Analysis-_Rock&oldid=687702" Category: Definitions What links here Related changes Special pages Printable version Permanent link Browse properties

113

from Isotope Production Facility  

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

Cancer-fighting treatment gets boost from Isotope Production Facility April 13, 2012 Isotope Production Facility produces cancer-fighting actinium 2:32 Isotope cancer treatment...

114

Isotope studies in photosynthesis  

Science Journals Connector (OSTI)

Isotope studies in photosynthesis ... Examines the use of isotopic oxygen, hydrogen, carbon, and phosphorus in the study of photosynthesis. ...

J. A. Bassham; A. A. Benson; Melvin Calvin

1953-01-01T23:59:59.000Z

115

Determination of Depleted Uranium in Urine via Isotope Ratio Measurements Using Large-Bore Direct Injection High Efficiency Nebulizer–Inductively Coupled Plasma Mass Spectrometry  

Science Journals Connector (OSTI)

Inductively coupled plasma mass spectrometry (ICP-MS), coupled with a large-bore direct injection high efficiency nebulizer (LB-DIHEN), was utilized to determine the concentration and...

Westphal, Craig S; McLean, John A; Hakspiel, Shelly J; Jackson, William E; McClain, David E; Montaser, Akbar

2004-01-01T23:59:59.000Z

116

Isotope Effects on the Enzymatic and Nonenzymatic Reactions of Chorismate  

Science Journals Connector (OSTI)

The isotopic composition of the latter was determined by isotope ratio mass spectrometry, enabling determination of isotope effects at the mechanistically interesting key positions O7, C1, and C9. ... Heavy atom isotope effects on the nonenzymatic Claisen rearrangement to give prephenate, 18k1 and 13k1, were determined at 60 °C as described for the enzymatic reactions and calculated from the following relationship: where xk1 is the apparent isotope effect, expressed as a ratio of the rate constants for the light and heavy (x) isotopes. ...

S. Kirk Wright; Michael S. DeClue; Ajay Mandal; Lac Lee; Olaf Wiest; W. Wallace Cleland; Donald Hilvert

2005-08-27T23:59:59.000Z

117

Manifestation and Origin of the Isotope Effect  

E-Print Network [OSTI]

This article reviews from one point of view the current status of the manifestations of isotope effect in a nuclear, atomic and molecular as well as solid state physics. Although these manifestations vary, they have one common feature - they all depend on mass. At present time the Standard Model can't explain the origin of the mass of elementary particles and their hierarchy. The last one don't permit to find the origin of the isotope effect.

V. G. Plekhanov

2009-07-12T23:59:59.000Z

118

Masses of Kr-77 and Kr-75  

E-Print Network [OSTI]

PHYSICAL REVIEW C VOLUME 35, NUMBER 4 Masses of Kr and Kr APRIL 1987 D. M. Moltz Nuclear Science Division, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 A. C. Betker, J. P. Sullivan, R. H. Burch, C. A... determinations of neutron deficient nu- clei between the 1f7/2 and lg9/2 shells are hampered by low production cross sections and complex decay schemes. The direct mass measurements' of the rubidium isotopes have provided a substantial base for other...

Moltz, D. M.; Betker, A. C.; Sullivan, J. P.; Burch, R. H.; Gagliardi, Carl A.; Tribble, Robert E.; Toth, K. S.; Avignone, F. T.

1987-01-01T23:59:59.000Z

119

Neutrinoless double beta decay and neutrino masses  

Science Journals Connector (OSTI)

Neutrinoless double beta decay (0???) is a promising test for lepton number violating physics beyond the standard model (SM) of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular we will discuss the relation between 0??? and Majorana neutrino masses provided by the so-called Schechter-Valle theorem in a quantitative way. Furthermore we will present an experimental cross check to discriminate 0??? from unknown nuclear background using only one isotope i.e. within one experiment.

Michael Duerr

2012-01-01T23:59:59.000Z

120

Kinetics of the Reaction of the Heaviest Hydrogen Atom with H2, the 4He? + H2 -> 4He?? + H Reaction: Experiments, Accurate Quantal Calculations, and Variational Transition State Theory, including Kinetic Isotope Effects for a Factor of 36.1 in Isotopic Mass  

SciTech Connect (OSTI)

The neutral muonic helium atom {sup 4}He{mu}, in which one of the electrons of He is replaced by a negative muon, may be effectively regarded as the heaviest isotope of the hydrogen atom, with a mass of 4.115 amu. We report details of the first muon spin rotation ({mu}SR) measurements of the chemical reaction rate constant of {sup 4}He{mu} with molecular hydrogen, {sup 4}He{mu} + H{sub 2} {yields} {sup 4}He{mu}H + H, at temperatures of 295.5, 405, and 500 K, as well as a {mu}SR measurement of the hyperfine coupling constant of muonic He at high pressures. The experimental rate constants, k{sub He{mu}}, are compared with the predictions of accurate quantum mechanical (QM) dynamics calculations carried out on a well converged Born-Huang (BH) potential energy surface, based on complete configuration interaction calculations and including a Born-Oppenheimer diagonal correction. At the two highest measured temperatures the agreement between the quantum theory and experiment is good to excellent, well within experimental uncertainties that include an estimate of possible systematic error, but at 295.5 K the quantum calculations for k{sub He{mu}} are below the experimental value by 2.1 times the experimental uncertainty estimates. Possible reasons for this discrepancy are discussed. Variational transition state theory calculations with multidimensional tunneling have also been carried out for k{sub He{mu}} on the BH surface, and they agree with the accurate QM rate constants to within 30% over a wider temperature range of 200-1000 K. Comparisons between theory and experiment are also presented for the rate constants for both the D + H{sub 2} and Mu + H{sub 2} reactions in a novel study of kinetic isotope effects for the H + H{sub 2} reactions over a factor of 36.1 in isotopic mass of the atomic reactant.

Fleming, Donald G.; Arseneau, Donald J.; Sukhorukov, Oleksandr; Brewer, Jess H.; Mielke, Steven L.; Truhlar, Donald G.; Schatz, George C.; Garrett, Bruce C.; Peterson, Kirk A.

2011-11-14T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

The Quest for the Heaviest Uranium Isotope  

E-Print Network [OSTI]

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.

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

2011-07-06T23:59:59.000Z

122

Galactic Chemical Evolution Redux: Atomic Numbers 6 < Z < 15  

E-Print Network [OSTI]

Motivated by the inability of Galactic chemical evolution models to reproduce some of the observed solar neighbourhood distribution of elements (and isotopes) with atomic numbers 6 < Z < 15, we have revisited the relevant stellar and Galactic models as part of an ambitious new program aimed at resolving these long-standing discrepancies. Avoiding the use of (traditional) parametric models for low- and intermediate-mass stellar evolution, we have generated a new, physically self-consistent, suite of stellar models and integrated the nucleosynthetic outputs into GEtool, our semi-analytical galactic chemical evolution software package. The predicted temporal evolution of several light- and intermediate-mass elements (and their isotopes) in the solar neighbourhood - from carbon to phosphorus - demonstrate the efficacy of the new yields in reconciling theory and observation.

B. K. Gibson; Y. Fenner; A. Kiessling

2005-02-15T23:59:59.000Z

123

Strategic Isotope Production | ornl.gov  

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

Strategic Isotope Strategic Isotope Production SHARE Strategic Isotope Production Typical capsules used in the transport of 252Cf source material inside heavily shielded shipping casks. ORNL's unique facilities at the High Flux Isotope Reactor (HFIR), Radiochemical Engineering Development Center (REDC), Irradiated Fuels Examination Laboratory (IFEL), and Irradiated Materials Examination Testing facility (IMET) are routinely used in the production, purification, packaging, and shipping of a number of isotopes of national importance, including: 75Se, 63Ni, 238Pu, 252Cf, and others. The intense neutron flux of the HFIR (2.0 x 1015 neutrons/cm²·s) permits the rapid formation of such isotopes. These highly irradiated materials are then processed and packaged for shipping using the facilities at the REDC, IFEL, and IMET.

124

Final Report, NEAC Subcommittee for Isotope Research & Production Planning  

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

Final Report, NEAC Subcommittee for Isotope Research & Production Final Report, NEAC Subcommittee for Isotope Research & Production Planning Final Report, NEAC Subcommittee for Isotope Research & Production Planning Isotopes, including both radioactive and stable isotopes, make important contributions to research, medicine, and industry in the United States and throughout the world. For nearly fifty years, the Department of Energy (DOE) has actively promoted the use of isotopes by funding (a) production of isotopes at a number of national laboratories with unique nuclear reactors or particle accelerators, (b) nuclear medicine research at the laboratories and in academia, (c) research into industrial applications of isotopes, and (d) research into isotope production and processing methods. The radio- pharmaceutical and radiopharmacy industries have their origin in

125

NACRE II: an update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number $A < 16$  

E-Print Network [OSTI]

An update of the NACRE compilation [Angulo et al., Nucl. Phys. A 656 (1999) 3] is presented. This new compilation, referred to as NACRE II, reports thermonuclear reaction rates for 34 charged-particle induced, two-body exoergic reactions on nuclides with mass number $A<16$, of which fifteen are particle-transfer reactions and the rest radiative capture reactions. When compared with NACRE, NACRE II features in particular (1) the addition to the experimental data collected in NACRE of those reported later, preferentially in the major journals of the field by early 2013, and (2) the adoption of potential models as the primary tool for extrapolation to very low energies of astrophysical $S$-factors, with a systematic evaluation of uncertainties. As in NACRE, the rates are presented in tabular form for temperatures in the $10^{6}$ $\\simeq\\leq$ T $\\leq$ $10^{10}$ K range. Along with the 'adopted' rates, their low and high limits are provided. The new rates are available in electronic form as part of the Brussels Library (BRUSLIB) of nuclear data. The NACRE II rates also supersede the previous NACRE rates in the Nuclear Network Generator (NETGEN) for astrophysics. [http://www.astro.ulb.ac.be/databases.html.

Yi Xu; Kohji Takahashi; Stephane Goriely; Marcel Arnould; Masahisa Ohta; Hiroaki Utsunomiya

2013-10-26T23:59:59.000Z

126

lead-isotope dating  

Science Journals Connector (OSTI)

lead-isotope dating, lead-lead dating, lead-isotope age measurement, lead-lead age measurement ? Blei-Isotopen(-Alters)bestimmung, f, Blei-Isotopen-Datierung

2014-08-01T23:59:59.000Z

127

isotopic ratio | EMSL  

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

isotopic ratio isotopic ratio Leads No leads are available at this time. Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. Abstract: As a candidate...

128

UV-frequency metrology on CO (a{sup 3}{Pi}): Isotope effects and sensitivity to a variation of the proton-to-electron mass ratio  

SciTech Connect (OSTI)

UV-frequency metrology has been performed on the a{sup 3}{Pi} - X{sup 1}{Sigma}{sup +} (0,0) band of various isotopologues of CO using a frequency-quadrupled injection-seeded narrow-band pulsed titanium:sapphire laser referenced to a frequency comb laser. The band origin is determined with an accuracy of 5 MHz ({delta}{nu}/{nu}=3x10{sup -9}), while the energy differences between rotational levels in the a{sup 3}{Pi} state are determined with an accuracy of 500 kHz. From these measurements, in combination with previously published radio-frequency and microwave data, a set of molecular constants is obtained that describes the level structure of the a{sup 3}{Pi} state of {sup 12}C{sup 16}O and {sup 13}C{sup 16}O with improved accuracy. Transitions in the different isotopologues are well reproduced by scaling the molecular constants of {sup 12}C{sup 16}O via the common mass-scaling rules. Only the value of the band origin could not be scaled, indicative of a breakdown of the Born-Oppenheimer approximation. Our analysis confirms the extreme sensitivity of two-photon microwave transitions between nearly degenerate rotational levels of different {Omega} manifolds for probing a possible variation of the proton-to-electron mass ratio, {mu}=m{sub p}/m{sub e}, on a laboratory time scale.

Nijs, Adrian J. de; Salumbides, Edcel J.; Eikema, Kjeld S. E.; Ubachs, Wim; Bethlem, Hendrick L. [Institute for Lasers, Life and Biophotonics Amsterdam, VU University, De Boelelaan 1081, NL-1081 HV Amsterdam (Netherlands)

2011-11-15T23:59:59.000Z

129

Standard test method for analysis of urine for uranium-235 and uranium-238 isotopes by inductively coupled plasma-mass spectrometry  

E-Print Network [OSTI]

1.1 This test method covers the determination of the concentration of uranium-235 and uranium-238 in urine using Inductively Coupled Plasma-Mass Spectrometry. This test method can be used to support uranium facility bioassay programs. 1.2 This method detection limits for 235U and 238U are 6 ng/L. To meet the requirements of ANSI N13.30, the minimum detectable activity (MDA) of each radionuclide measured must be at least 0.1 pCi/L (0.0037 Bq/L). The MDA translates to 47 ng/L for 235U and 300 ng/L for 238U. Uranium– 234 cannot be determined at the MDA with this test method because of its low mass concentration level equivalent to 0.1 pCi/L. 1.3 The digestion and anion separation of urine may not be necessary when uranium concentrations of more than 100 ng/L are present. 1.4 Units—The values stated in picoCurie per liter units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1....

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

130

Proton elastic scattering from tin isotopes at 295 MeV and systematic change of neutron density distributions  

E-Print Network [OSTI]

Cross sections and analyzing powers for proton elastic scattering from $^{116,118,120,122,124}$Sn at 295 MeV have been measured for a momentum transfer of up to about 3.5 fm$^{-1}$ to deduce systematic changes of the neutron density distribution. We tuned the relativistic Love-Franey interaction to explain the proton elastic scattering of a nucleus whose density distribution is well known. Then, we applied this interaction to deduce the neutron density distributions of tin isotopes. The result of our analysis shows the clear systematic behavior of a gradual increase in the neutron skin thickness of tin isotopes with mass number.

S. Terashima; H. Sakaguchi; H. Takeda; T. Ishikawa; M. Itoh; T. Kawabata; T. Murakami; M. Uchida; Y. Yasuda; M. Yosoi; J. Zenihiro; H. P. Yoshida; T. Noro; T. Ishida; S. Asaji; T. Yonemura

2008-01-20T23:59:59.000Z

131

Early Days of Accelerator Mass Spectrometry  

DOE R&D Accomplishments [OSTI]

Alvarez reviews his role in the development of the tandem Van de Graaff accelerator and the technique of accelerator mass spectrometry as a technique for isotope dating. (GHT)

Alvarez, L. W.

1981-05-00T23:59:59.000Z

132

INTRODUCTION The oxygen isotopic compositions of minerals  

E-Print Network [OSTI]

- perature and aridity is not so well understood. Because the middle Holocene was a period of elevated solar 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

González, Luis A.

133

AVLIS enrichment of medical isotopes  

SciTech Connect (OSTI)

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.

Haynam, C.A.; Scheibner, K.F.; Stern, R.C.; Worden, E.F. [Lawrence Livermore National Laboratory, CA (United States)

1996-12-31T23:59:59.000Z

134

Triple Oxygen Isotope Measurement of Nitrate to Analyze Impact of Aircraft Emissions  

E-Print Network [OSTI]

P. ; Craig, H. Atmospheric oxygen: isotopic composition andM.H. 1986. A non-mass-dependent oxygen isotope effect in theof ozone from molecular oxygen: the role of symmetry in

Chan, Sharleen

135

Isotope Science and Production  

E-Print Network [OSTI]

of Energy National Isotope Program http://www.nuclear.energy.gov/isotopes/nelsotopes2a.html Isotopes for Environmental Science Isotopes produced at Los Alamos National Laboratory are used as environmental tracers change and its effects. Los Alamos National Laboratory can produce Si-32 needed for oceanographic tracing

136

Stable isotope studies  

SciTech Connect (OSTI)

The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs.

Ishida, T.

1992-01-01T23:59:59.000Z

137

Method for enriching a middle isotope using vibration-vibration pumping  

DOE Patents [OSTI]

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.

Rich, Joseph W. (East Aurora, NY); Homicz, Gregory F. (Getzville, NY); Bergman, Richard C. (Corfu, NY)

1989-01-01T23:59:59.000Z

138

Magnesium Isotopes in Halo Stars  

E-Print Network [OSTI]

We have determined Mg isotope ratios in halo field dwarfs and giants in the globular cluster M71 based on high S/N high spectral resolution (R = 10$^5$) Keck HIRES spectra. Unlike previous claims of an important contribution from intermediate-mass AGB stars to the Galactic halo, we find that our $^{26}$Mg/$^{24}$Mg ratios can be explained by massive stars.

Jorge Melendez; Judith G. Cohen

2007-08-29T23:59:59.000Z

139

Isotopically pumped isotopic CF4 laser  

Science Journals Connector (OSTI)

Single-mode optical pumping of CF4 to generate 16-µm frequencies has been extended to include the isotopic species 12CF4,...

Eckhardt, Roger; Telle, John; Haynes, Larry

1982-01-01T23:59:59.000Z

140

Isotope Geothermometry | Open Energy Information  

Open Energy Info (EERE)

Isotope Geothermometry Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Isotope Geothermometry Details Activities (0) Areas (0) Regions (0)...

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

THE ISOTOPES OF AMERICIUM  

E-Print Network [OSTI]

spectrographic analysis of the americium samples. It is a48 J'---_I" THE ISOTOPES OF AMERICIUM K. Street, Jr. , A.Elements THE ISOTOPES OF AMERICIUM K. Street, Jr. , A.

Street, K.; Ghiroso, A.; Seaborg, G.T.

2008-01-01T23:59:59.000Z

142

Stable Isotope Tracers in the Life Sciences and Medicine  

Science Journals Connector (OSTI)

...the result of cumulative isotope effects...reduced carbon + oils HCO3z solid carbonates...medicine. As production of stable isotopes...Meyerson and E. K. Fields, Science 166...H. Kollman, Production of Algae Containing...et al., Mass Production of Chlorella...Chicago, Chicago, Illinois. The present...

N. A. Matwiyoff; D. G. Ott

1973-09-21T23:59:59.000Z

143

Measuring the Isotopic Composition of Solar Wind Noble Gases  

E-Print Network [OSTI]

noble gases. #12;Exploring the Solar Wind94 Light solar wind noble gases were directly measured by mass of the light gases are known to vary with energy, so none of these provided solar isotopic and elemental5 Measuring the Isotopic Composition of Solar Wind Noble Gases Alex Meshik, Charles Hohenberg, Olga

144

Isotope Effect in Adhesion  

Science Journals Connector (OSTI)

Isotope Effect in Adhesion ... We report the first observation of an isotope effect in adhesion. ... The results are presented in Figure 3. Clearly, the isotope effect is very significant, substantiating the proposed H-bonding interactions between the PDMS and Si?OH(D) surfaces. ...

Gun Young Choi; Abraham Ulman; Yitzhak Shnidman; Walter Zurawsky; Cathy Fleischer

2000-05-25T23:59:59.000Z

145

Using phylogenetic probes for quantification of stable isotope labeling and microbial community analysis  

DOE Patents [OSTI]

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).

Brodie, Eoin L; DeSantis, Todd Z; Karaoz, Ulas; Andersen, Gary L

2014-12-09T23:59:59.000Z

146

Osmium isotope systematics in Witwatersrand and Bushveld ore deposits  

Science Journals Connector (OSTI)

...isotopes Klipfontein Concentrator laurite Loraine Mine mass spectra Merensky Reef metal...mineral concentrateswere obtainedfrom the Loraine,PresidentBrand,andPresidentSteyn goldmines...outsidethe generalpopulation(1.371, Loraine; 0.996, PresidentBrand);18 additionalgrainsfrom...

S. R. Hart; E. D. Kinloch

147

Evidence of magnetic isotope effects during thermochemical sulfate reduction  

E-Print Network [OSTI]

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 ...

Oduro, Harry D.

148

A biomarker based on the stable isotopes of nickel  

Science Journals Connector (OSTI)

...archaeon that grows in atmospheric air . Archaea 1 : 113...inductively coupled plasma mass spectrometry...isotopic compositions by plasma-source mass spectrometry...multiple-collector plasma source mass spectrometry...analysis of Fe by thermal ionization...Research Support, Non-U.S. Gov't...

Vyllinniskii Cameron; Derek Vance; Corey Archer; Christopher H. House

2009-01-01T23:59:59.000Z

149

ARM - Measurement - Isotope ratio  

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

govMeasurementsIsotope ratio govMeasurementsIsotope ratio ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Isotope ratio Ratio of stable isotope concentrations. Categories Atmospheric Carbon, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments FLASK : Flask Samplers for Carbon Cycle Gases and Isotopes Field Campaign Instruments FLASK : Flask Samplers for Carbon Cycle Gases and Isotopes Datastreams FLASK : Flask Samplers for Carbon Cycle Gases and Isotopes

150

Laser Isotope Enrichment for Medical and Industrial Applications  

SciTech Connect (OSTI)

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".

Leonard Bond

2006-07-01T23:59:59.000Z

151

Isotope Program Transportation | Department of Energy  

Office of Environmental Management (EM)

Isotope Program Transportation Isotope Program Transportation Isotope Program Transportation More Documents & Publications Nuclear Fuel Storage and Transportation Planning Project...

152

Magnetic moments of long isotopic chains  

E-Print Network [OSTI]

Dipole magnetic moments of several long isotopic chains are analyzed within the self-consistent Finite Fermi System theory based on the Generalized Energy Density Functional method with exact account for the pairing and quasi-particle continuum. New data for nuclei far from the beta-stability valley are included in the analysis. For a number of semi-magic isotopes of the tin and lead chains a good description of the data is obtained, with accuracy of 0.1 - 0.2 mu_N. A chain of non-magic isotopes of copper is also analyzed in detail. It is found that the systematic analysis of magnetic moments of this long chain yields rich information on the evolution of the nuclear structure of the Cu isotopes. In particular, it may give a signal of deformation for the ground state of some nuclei in the chain.

I. N. Borzov; E. E. Saperstein; S. V. Tolokonnikov; G. Neyens; N. Severijns

2008-04-28T23:59:59.000Z

153

Hybrid isotope separation scheme  

DOE Patents [OSTI]

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.

Maya, J.

1991-06-18T23:59:59.000Z

154

Hybrid isotope separation scheme  

DOE Patents [OSTI]

A method of 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.

Maya, Jakob (Brookline, MA)

1991-01-01T23:59:59.000Z

155

Description of the even samarium isotopes in the collective pair approximation  

Science Journals Connector (OSTI)

A microscopic multi-j shell calculation is performed to describe the structure of the ground states of the even Sm isotopes within the pairing plus quadrupole model and in the collective pair approximation. Agreement with the experimental data is found for both quadrupole deformation ? and for the diffusivity of the Fermi surface. The variation with the mass number of the structure of the proton and neutron collective pairs is discussed in connection with the increased role of the quadrupole-quadrupole interaction and of the Pauli principle.

F. Catara; A. Insolia; E. Maglione; A. Vitturi

1984-05-01T23:59:59.000Z

156

Stable isotope enrichment  

SciTech Connect (OSTI)

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

Egle, Brian

2014-07-14T23:59:59.000Z

157

EMSL - isotopic ratio  

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

isotopic-ratio en Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. http:www.emsl.pnl.govemslwebpublicationsmagnesium-behavior-and-structural-def...

158

Mass, quark-number, and sqrt sNN dependence of the second andfourth flow harmonics in ultra-relativistic nucleus-nucleuscollisions  

SciTech Connect (OSTI)

We present STAR measurements of the azimuthal anisotropyparameter v_2 for pions, kaons, protons, Lambda, bar Lambda, Xi+bar Xi,and \\Omega + bar Omega, along with v_4 for pions, kaons, protons, andLambda + bar Lambda at mid-rapidity for Au+Au collisions at sqrt sNN=62.4and 200 GeV. The v_2(p_T) values for all hadron species at 62.4 GeV aresimilar to those observed in 130 and 200 GeV collisions. For observedkinematic ranges, v_2 values at 62.4, 130, and 200 GeV are as little as10 percent-15 percent larger than those in Pb+Pb collisions at sqrt s NN=17.3 GeV. At intermediate transverse momentum (p_T from 1.5-5 GeV/c),the 62.4 GeV v_2(p_T) and v_4(p_T) values are consistent with thequark-number scaling first observed at 200 GeV. A four-particle cumulantanalysis is used to assess the non-flow contributions to pions andprotons and some indications are found for a smaller non-flowcontribution to protons than pions. Baryon v_2 is larger than anti-baryonv_2 at 62.4 and 200 GeV perhaps indicating either that the initialspatial net-baryon distribution is anisotropic, that the mechanismleading to transport of baryon number from beam- to mid-rapidity enhancesv_2, or that anti-baryon and baryon annihilation is larger in thein-plane direction.

Abelev, B.I.; Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett,J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Bai,Y.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellingeri-Laurikainen, A.; Bellwied, R.; Benedosso, F.; Bhardwaj, S.; Bhasin, A.; Bhati, A.K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L.C.; Blyth, S.-L.; Bonner, B.E.; Botje, M.; Bouchet, J.; Brandin, A.V.; Bravar, A.; Bystersky, M.; Cadman, R.V.; Cai,X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Castillo, J.; Catu,O.; Cebra, D.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen,H.F.; Chen, J.H.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cosentino, M.R.; Cramer, J.G.; Crawford,H.J.; Das, D.; Das, S.; Daugherity, M.; de Moura, M.M.; Dedovich, T.G.; DePhillips, M.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Djawotho,P.; Dogra, S.M.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dunin, V.B.; Dunlop, J.C.; Dutta Mazumdar, M.R.; Eckardt, V.; Edwards, W.R.; Efimov,L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch,E.; Fine, V.; Fisyak, Y.; Fu, J.; Gagliardi, C.A.; Gaillard, L.; Ganti,M.S.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.S.; Gorbunov, Y.G.; Gos,H.; Grebenyuk, O.; Grosnick, D.; Guertin, S.M.; Guimaraes, K.S.F.F.; Guo,Y.; Gupta, N.; Gutierrez, T.D.; Haag, B.; Hallman, T.J.; Hamed, A.; Harris, J.W.; He, W.; Heinz, M.; Henry, T.W.; Hepplemann, S.; Hippolyte,B.; Hirsch, A.; Hjort, E.; Hoffman, A.M.; Hoffmann, G.W.; Horner, M.J.; Huang, H.Z.; Huang, S.L.; Hughes, E.W.; Humanic, T.J.; Igo, G.; Jacobs,P.; Jacobs, W.W.; Jakl, P.; Jia, F.; Jiang, H.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Khodyrev, V.Yu.; Kim, B.C.; Kiryluk, J.; Kisiel, A.; Kislov, E.M.; Klein,S.R.; Kocoloski, A.; Koetke, D.D.; et al.

2007-01-06T23:59:59.000Z

159

Isotopic Resonance Hypothesis: Experimental Verification by Escherichia coli Growth Measurements  

E-Print Network [OSTI]

Isotopic composition of reactants affects the rates of chemical and biochemical reactions. As a rule, enrichment of heavy stable isotopes leads to slower reactions. But the recent isotopic resonance hypothesis suggests that the dependence of the reaction rate upon the enrichment degree is not monotonous; instead, at some resonance isotopic compositions, the kinetics increases, while at off resonance compositions the same reactions progress slower. To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error plus or minus 0.05%) experiment to measure the bacterial growth parameters in minimal media with varying isotopic compositions. A number of predicted resonance conditions were tested, which kinetic enhancements as strong as plus 3% discovered at these conditions. The combined evidence extremely strongly supports the existence of isotopic resonances. This phenomenon has numerous implications for the origin of life and astrobiology, and possible application...

Xie, Xueshu

2014-01-01T23:59:59.000Z

160

Anomalous isotopic composition of cosmic rays  

SciTech Connect (OSTI)

Recent measurements of nonsolar isotopic patterns for the elements neon and (perhaps) magnesium in cosmic rays are interpreted within current models of stellar nucleosynthesis. One possible explanation is that the stars currently responsible for cosmic-ray synthesis in the Galaxy are typically super-metal-rich by a factor of two to three. Other possibilities include the selective acceleration of certain zones or masses of supernovas or the enhancement of /sup 22/Ne in the interstellar medium by mass loss from red giant stars and planetary nebulas. Measurements of critical isotopic ratios are suggested to aid in distinguishing among the various possibilities. Some of these explanations place significant constraints on the fraction of cosmic ray nuclei that must be fresh supernova debris and the masses of the supernovas involved. 1 figure, 3 tables.

Woosley, S.E.; Weaver, T.A.

1980-06-20T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Celebrating The Isotope  

Science Journals Connector (OSTI)

Celebrating The Isotope ... The notion of isotopes and the rest of Soddy’s lifetime body of work on radioactivity, the group displacement laws, the social responsibility of scientists, and the environment have had a profound effect on science and society. ...

GEORGE B. KAUFFMAN

2013-12-02T23:59:59.000Z

162

Isotope - based Quantum Information  

E-Print Network [OSTI]

This paper is brief review of three aspects of the isotope - based quantum information: computation, teleportation and cryptography. Our results demonstrate not only that entanglement exists in elementary excitation of isotope - mixed solids but also it can be used for quantum information processing.

Vladimir G. Plekhanov

2009-09-04T23:59:59.000Z

163

Isotopic Analysis- Fluid At Lightning Dock Geothermal Area (Witcher...  

Open Energy Info (EERE)

Number DE-FC07-00AL66977 Notes This project deepened a well and took 4 samples from wells around the Lightning Docks KGRA and performed extensive chamical and isotope analysis...

164

Isotope Geothermometry At Lightning Dock Geothermal Area (Witcher...  

Open Energy Info (EERE)

Number DE-FC07-00AL66977 Notes This project deepened a well and took 4 samples from wells around the Lightning Docks KGRA and performed extensive chamical and isotope analysis...

165

Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Area (White,  

Open Energy Info (EERE)

Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Area (White, Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Area (White, Et Al., 1992) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Area (White, Et Al., 1992) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Isotopic Analysis- Fluid Activity Date Usefulness not indicated DOE-funding Unknown Notes Used various geochemical techniques to obtain data from which information regarding mass transfer rates. This then led to conclucions of the history/evolution of the geothermal system. Unclear whether useful for exploration purposes. References Art F. White, Nancy J. Chuma, Fraser Goff (1992) Mass Transfer Constraints On The Chemical Evolution Of An Active Hydrothermal System,

166

Uncertainty analysis of densities and isotopics: Handling correlations  

SciTech Connect (OSTI)

This paper discusses two cases of correlated parameters in uncertainty analyses: (1) the case of measured mass, density, and volume or spatial dimension correlations; and (2) the case of measured material isotopics, where increasing one atom fraction must cause the others to decrease. In the first case, an equation is derived that has a term due to uncertain density, a term due to uncertain dimensions, and a term due to the correlation between density and dimensions. In a numerical test problem, this equation gives the same result as the standard equation that treats mass and dimensions independently. In the case of isotopics, an equation is derived relating the uncertainty due to uncertain isotopic fractions to the sensitivities to isotopic densities, which are easier to calculate. The equation is verified in a test problem. (authors)

Favorite, J. A.; Armstrong, J. C. [X-Computational Physics Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Burr, T. [Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

2013-07-01T23:59:59.000Z

167

Isotopic Composition of Solar Wind Calcium: First in Situ Measurement by CELIAS/MTOF on Board SOHO  

E-Print Network [OSTI]

We present first results on the Ca isotopic abundances derived from the high resolution Mass Time-of-Flight (MTOF) spectrometer of the charge, element, and isotope analysis system (CELIAS) experiment on board the Solar and Heliospheric Observatory (SOHO). We obtain isotopic ratios 40Ca/42Ca = (128+-47) and 40Ca/44Ca = (50+-8), consistent with terrestrial values. This is the first in situ determination of the solar wind calcium isotopic composition and is important for studies of stellar modeling and solar system formation since the present-day solar Ca isotopic abundances are unchanged from their original isotopic composition in the solar nebula.

R. Kallenbach; F. M. Ipavich; P. Bochsler; S. Hefti; P. Wurz; M. R. Aellig; A. B. Galvin; J. Geiss; F. Gliem; G. Gloeckler; H. Grunwaldt; M. Hilchenbach; D. Hovestadt; B. Klecker

1998-02-07T23:59:59.000Z

168

Correction of accurate mass measurement for target compound verification by quadrupole time-of-flight mass spectrometry  

Science Journals Connector (OSTI)

The aim of this work is to evaluate quadrupole/time-of-flight (QTOF) mass spectrometry for simultaneous measurement of accurate mass and quantification of a target by using a stable isotopically labeled intern...

Harald C. Köfeler…

2005-03-01T23:59:59.000Z

169

Stable Carbon Isotope Ratios of Phenolic Compounds in Secondary Particulate Organic Matter Formed by Photooxidation of Toluene  

E-Print Network [OSTI]

Compound-specific stable carbon isotope ratios for phenolic compounds in secondary particulate organic matter (POM) formed by photooxidation of toluene were studied. Secondary POM generated by photooxidation of toluene using a continuous-flow reactor and an 8 cubic meter indoor smog chamber was collected, and then extracted with acetonitrile. Eight phenolic compounds were identified in the extracts by a gas chromatograph coupled with a mass spectrometer, and their compound-specific stable carbon isotope ratios were determined by a gas chromatograph coupled with a combustion furnace followed by an isotope ratio mass spectrometer. The majority of the products, including methylnitrophenols and methylnitrocatechols, were isotopically depleted by 5 to 6 permil compared to the initial isotope ratio for toluene, whereas the isotope ratio for 4_nitrophenol remained the same as the initial isotope ratio for toluene. Based on the reaction mechanisms postulated in literature, stable carbon isotope ratios of these produc...

Irei, Satoshi; Huang, Lin; Auld, Janeen; Collin, Fabrice; Hastie, Donald

2014-01-01T23:59:59.000Z

170

lead-isotope age  

Science Journals Connector (OSTI)

lead-isotope age, lead-lead age [An age in years calculated from the ratio of lead-207 to lead-206, a by-product of the uranium-thorium-lead age method] ? Blei-Isotopen-Alter n

2014-08-01T23:59:59.000Z

171

ISOTOPES IN WATER  

Science Journals Connector (OSTI)

The study of isotopic prosies ha two different though related basic aims: an understanding of the way in which the water cycle in linked to alterations in climate, and how the carbon cycle has responded to the...

W. GEORGE DARLING; ADRIAN H. BATH…

2006-01-01T23:59:59.000Z

172

Nuclear isotope thermometry  

Science Journals Connector (OSTI)

We discuss different aspects which might influence temperatures deduced from experimental isotopic yields in the multifragmentation process. It is shown that fluctuations due to the finite size of the system and distortions due to the decay of hot primary fragments conspire to blur the temperature determination in multifragmentation reactions. These facts suggest that caloric curves obtained through isotope thermometers, which were taken as evidence for a first-order phase transition in nuclear matter, should be investigated very carefully.

S. R. Souza, W. P. Tan, R. Donangelo, C. K. Gelbke, W. G. Lynch, and M. B. Tsang

2000-11-10T23:59:59.000Z

173

Trace, isotopic analysis of micron-sized grains -- Mo, Zr analysis of stardust (SiC and graphite grains).  

SciTech Connect (OSTI)

Secondary Neutral Mass Spectrometry using resonant laser ionization can provide for both high useful yields and high discrimination while maintaining high lateral and depth resolutions. An example of the power of the method is measurement of the isotopic composition of Mo and Zr in 1-5 {micro}m presolar SiC and graphite grains isolated from the Murchison CM2 meteorite for the first time. These grains have survived the formation of the Solar System and isotopic analysis reveals a record of the stellar nucleosynthesis present during their formation. Mo and Zr, though present at less than 10 ppm in some grains, are particularly useful in that among their isotopes are members that can only be formed by distinct nucleosynthetic processes known as s-, p-, and r-process. Successful isotopic analysis of these elements requires both high selectivity (since these are trace elements) and high efficiency (since the total number of atoms available are limited). Resonant Ionization Spectroscopy is particularly useful and flexible in this application. While the sensitivity of this t.edmique has often been reported in the past, we focus hereon the very low noise properties of the technique. We further demonstrate the efficacy of noise removal by two complimentary methods. First we use the resonant nature of the signal to subtract background signal. Second we demonstrate that by choosing the appropriate resonance scheme background can often be dramatically reduced.

Pellin, M. J.; Nicolussi, G. K.

1998-02-19T23:59:59.000Z

174

Measurements of ISGMR in Sn, Cd and Pb isotopes and the asymmetry of nuclear matter incompressibility  

SciTech Connect (OSTI)

The compression-mode isoscalar giant monopole resonance (ISGMR) has been studied in the Sn, Cd and Pb isotopes using inelastic scattering of 400 MeV {alpha}-particles at extreme forward angles, including 0 deg. We have obtained completely 'background-free' inelastic-scattering spectra for the Sn, Cd, and Pb isotopes for a wide angular and excitation-energy range. The various giant resonances excited with different transferred angular momenta were extracted by a multipole-decomposition analysis (MDA). It was found that the centroid energies of the ISGMR in Sn isotopes are significantly lower than the theoretical predictions. The K{sub {tau}} in the empirical expression for the nuclear incompressibility has been determined to be K{sub {tau}} = -550{+-}100 MeV for the Sn isotopes. The extracted value for the Cd isotopes is K{sub {tau}} = -480{+-}100 MeV. These numbers are consistent with values of K{sub {tau}} = -370{+-}120 MeV obtained from an analysis of the isotopic transport ratios in medium-energy heavy-ion reactions, K{sub {tau}} -500{sub -100}{sup +120} MeV obtained from constraints placed by neutron-skin data from anti-protonic atoms across the mass table, and K{sub {tau}} = -500{+-}50 MeV obtained from theoretical calculations using different Skyrme interactions and relativistic mean field (RMF) Lagrangians. Stringent constraints on interactions employed in nuclear structure calculations are obtained on the basis of the experimentally determined values for K{sub {infinity}} and K{sub {tau}}. These parameters constrain as well the equation of state (EOS) of nuclear matter. However, a significant discrepancy still remains. The ISGMR positions in Sn and Cd isotopes are systematically lower than the predictions obtained on basis of determined from the ISGMR in {sup 208}Pb. This raises the question ''Why are Sn and Cd nuclei so soft?''. For a clue to solve the problem, we discuss the preliminary results on the exact positions of the ISGMR in {sup 204,206,208}Pb.

Fujiwara, M.; Hashimoto, H.; Nakanishi, K.; Okumura, S.; Yosoi, M. [Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047 (Japan); Li, T.; Patel, D.; Garg, U.; Berg, G. P. A.; Liu, Y.; Marks, R.; Matta, J.; Nayak, B. K.; Madhusudhana-Rao, P. V.; Long, A.; Sault, K.; Talwar, R. [JINA and Physics Department, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Ichikawa, M.; Itoh, M.; Matsuo, R. [Cyclotron and Radioisotope Center, Tohoku University, Sendai 980-8578 (Japan)

2011-10-28T23:59:59.000Z

175

Method for detecting and correcting for isotope burn-in during long-term neutron dosimetry exposure  

DOE Patents [OSTI]

A method is described for detecting and correcting for isotope burn-in during-long term neutron dosimetry exposure. In one embodiment, duplicate pairs of solid state track recorder fissionable deposits are used, including a first, fissionable deposit of lower mass to quantify the number of fissions occuring during the exposure, and a second deposit of higher mass to quantify the number of atoms of for instance .sup.239 Pu by alpha counting. In a second embodiment, only one solid state track recorder fissionable deposit is used and the resulting higher track densities are counted with a scanning electron microscope. This method is also applicable to other burn-in interferences, e.g., .sup.233 U in .sup.232 Th or .sup.238 Pu in .sup.237 Np.

Ruddy, Francis H. (Monroeville, PA)

1988-01-01T23:59:59.000Z

176

Atomic Spectroscopy and Separated Isotopes  

Science Journals Connector (OSTI)

The advantages in the use of separated isotopes in atomic spectroscopy for the determination of nuclear momentsI ? Q and for studies of the isotope-shift phenomena are discussed. Illustrations of spectra are given for mercury uranium and samarium. In addition a summary is given of twenty-two so-called problem nuclei i.e. those naturally occurring isotopes for which the nuclear moments are completely uncertain. Concluding remarks are made on such problems as the evaluation of the absolute magnitude of isotope shifts the role of “forbidden transitions” in isotope spectra and the potential future value of spectro-isotopic assay techniques.

J. R. McNally Jr.

1952-01-01T23:59:59.000Z

177

Radioactive Kr Isotopes  

Science Journals Connector (OSTI)

A radioactive isotope of 1.1-hour half-life has been produced in krypton by alpha-particle bombardment of Se74, enriched electromagnetically from 0.9 percent to 14.1 percent. Assignment of the isotope is made to Kr77. Aluminum absorption measurements indicate a positron end point of 1.7 Mev. In addition to annihilation radiation, gamma-rays and K-capture have been observed. The ratio of K-capture to positron emission from the Se74(?,n) reaction is computed as 2.6. The krypton 1.42-day isotope has been produced by an ?,n reaction on electromagnetically enriched Se76. The isotope is located as Kr79 and its half-life confirmed. A positron end point of 1.0 Mev is determined by aluminum absorption measurements. In addition to annihilation radiation, gamma-rays and K-capture have been observed. The ratio of K-capture to positron emission from the Se76(?,n) reaction is computed to be 50. The cross-section ratio for formation of Kr77 compared to Kr79 by alpha-particle bombardment of selenium is computed as 1.4. The 4.6-hour Kr85 isotope has been produced by a Se(?,n) reaction.

L. L. Woodward; D. A. Mccown; M. L. Pool

1948-10-01T23:59:59.000Z

178

Isotope separation apparatus  

DOE Patents [OSTI]

Isotope separation apparatus consisting of a plurality of cells disposed adjacent to each other in an evacuated container. A common magnetic field is established extending through all of the cells. A source of energetic electrons at one end of the container generates electrons which pass through the cells along the magnetic field lines. Each cell includes an array of collector plates arranged in parallel or in tandem within a common magnetic field. Sets of collector plates are disposed adjacent to each other in each cell. Means are provided for differentially energizing ions of a desired isotope by applying energy at the cyclotron resonant frequency of the desired isotope. As a result, the energized desired ions are preferentially collected by the collector plates.

Arnush, Donald (Rancho Palos Verdes, CA); MacKenzie, Kenneth R. (Pacific Palisades, CA); Wuerker, Ralph F. (Palos Verdes Estates, CA)

1980-01-01T23:59:59.000Z

179

GENERATION OF RADIOXENON ISOTOPES  

SciTech Connect (OSTI)

With the continued population of the International Monitoring System (IMS) network and the certification of radioxenon laboratory systems it has become necessary to calibrate and test these systems using as many of the radioxenon isotopes as possible. Several very promising techniques have been explored recently that allow for convenient production of Xe-133, Xe-131m, the short-lived isotope Xe-135, and even the difficult to obtain Xe-133m. IMS national and international laboratories have traditionally obtained Xe-133 from medical isotope suppliers. The activity of these medical dose samples is extremely high (~ 740 MBq) and requires very careful fume hood work to dilute down to appropriate levels (~ 10 Bq). By waiting for 10 or more half-lives it is possible to reduce the handling regimen considerably, while also obtaining a strong Xe-131m signature due to its longer half-life (11.9 days). The short-lived isotope Xe-135 (9.14 hrs) and the longer lived parent nuclide Xe-133m (2.2 day half-life) are never present in these samples. To obtain these isotopes another source or technique is required. This paper will discuss the two techniques developed and implemented at Pacific Northwest National Lab (PNNL) and show the results obtained from each technique. The first is an in-house method that allows for on demand production of two of these isotopes, Xe-133 and Xe-135, using HEU and a modest flux neutron source. The second method uses a research reactor at the Pullman campus of Washington State University to produce Xe-133, Xe-133m and Xe-135.

McIntyre, Justin I.; Pratt, Sharon L.; Bowyer, Ted W.; Cooper, Matthew W.; Hayes, James C.; Heimbigner, Tom R.; Hubbard, Charles W.; Miley, Harry S.; Ripplinger, Mike D.

2008-09-23T23:59:59.000Z

180

Analysis of a Uranium Solution for Evaluating the Total Number of Fissions in the JCO Criticality Accident in Tokai-mura  

Science Journals Connector (OSTI)

......LMRI, France). Determination of the concentration...spectrometer) for isotope ratio measurements...obtain an accurate isotope ratio without any fractionation...calibrating the mass bias. Determination of boron and metal impurities......

Gunzo Uchiyama; Kazuo Watanabe; Masakatsu Miyauchi; Yoshihiro Togashi; Yoshinori Nakahara; Hiroyuki Fukaya; Jun Inagawa; Daiske Suzuki; Takashi Sonoda; Nobuaki Kohno; Katsubumi Gunji; Mitsuo Ito; Takeshi Sato

2001-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

UNIT NUMBER:  

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

193 UNIT NUMBER: 197 UNIT NAME: CONCRETE RUBBLE PILE (30) REGULATORY STATUS: AOC LOCATION: Outside plant security fence, north of the plant on Big Bayou Creek on private property....

182

UNIT NUMBER  

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

7 UNIT NUMBER UNIT NAME Rubble oile 41 REGULATORY STATUS: AOC LOCATION: Butler Lake Dam, West end of Butler Lake top 20 ft wide, 10 ft APPROXIMATE DIMENSIONS: 200 ft long, base 30...

183

Selection of Isotopes and Elements for Fuel Cycle Analysis  

SciTech Connect (OSTI)

Fuel cycle system analysis simulations examine how the selection among fuel cycle options for reactors, fuel, separation, and waste management impact uranium ore utilization, waste masses and volumes, radiotoxicity, heat to geologic repositories, isotope-dependent proliferation resistance measures, and so forth. Previously, such simulations have tended to track only a few actinide and fission product isotopes, those that have been identified as important to a few criteria from the standpoint of recycled material or waste, taken as a whole. After accounting for such isotopes, the residual mass is often characterized as “fission product other” or “actinide other”. However, detailed assessment of separation and waste management options now require identification of key isotopes and residual mass for Group 1A/2A elements (Rb, Cs, Sr, Ba), inert gases (Kr, Xe), halogens (Br, I), lanthanides, transition metals, transuranic (TRU), uranium, actinide decay products. The paper explains the rationale for a list of 81 isotopes and chemical elements to better support separation and waste management assessment in dynamic system analysis models such as Verifiable Fuel Cycle Simulation (VISION)

Steven J. Piet

2009-04-01T23:59:59.000Z

184

LITERATURE SURVEY ON ISOTOPIC ABUNDANCE RATIO MEASUREMENTS - 2001-2005  

SciTech Connect (OSTI)

Along with my usual weekly review of the published literature for new nuclear data, I also search for new candidates for best measurements of isotopic abundances from a single source. Most of the published articles, that I previously had found in the Research Library at the Brookhaven Lab, have already been sent to the members of the Atomic Weights Commission, by either Michael Berglund or Thomas Walczyk. In the last few days, I checked the published literature for any other articles in the areas of natural variations in isotopic abundance ratios, measurements of isotopic abundance ratios on samples of extra-terrestrial material and isotopic abundance ratio measurements performed using ICPMS instruments. Hopefully this information will be of interest to members of the Commission, the sub-committee on isotopic abundance measurements (SIAM), members of the former sub-committee on natural isotopic fractionation (SNIF), the sub-committee on extra-terrestrial isotope ratios (SETIR), the RTCE Task Group and the Guidelines Task Group, who are dealing with ICPMS and TIMS comparisons. In the following report, I categorize the publications in one of four areas. Measurements performed using either positive or negative ions with Thermal Ionization Mass Spectrometer, TIMS, instruments; measurements performed on Inductively Coupled Plasma Mass Spectrometer, ICPMS, instruments; measurements of natural variations of the isotopic abundance ratios; and finally measurements on extra-terrestrial samples with instrumentation of either type. There is overlap in these areas. I selected out variations and ET results first and then categorized the rest of the papers by TIMS and ICPMS.

HOLDEN, N.E.

2005-08-13T23:59:59.000Z

185

Isotopic noble gas signatures released from medical isotope production facilities - Simulations and measurements  

SciTech Connect (OSTI)

Journal article on the role that radioxenon isotopes play in confirming whether or not an underground explosion was nuclear in nature. Radioxenon isotopes play a major role in confirming whether or not an underground explosion was nuclear in nature. It is then of key importance to understand the sources of environmental radioxenon to be able to distinguish civil sources from those of a nuclear explosion. Based on several years of measurements, combined with advanced atmospheric transport model results, it was recently shown that the main source of radioxenon observations are strong and regular batch releases from a very limited number of medical isotope production facilities. This paper reviews production processes in different medical isotope facilities during which radioxenon is produced. Radioxenon activity concentrations and isotopic compositions are calculated for six large facilities. The results are compared with calculated signals from nuclear explosions. Further, the outcome is compared and found to be consistent with radioxenon measurements recently performed in and around three of these facilities. Some anomalies in measurements in which {sup 131m}Xe was detected were found and a possible explanation is proposed. It was also calculated that the dose rate of the releases is well below regulatory values. Based on these results, it should be possible to better understand, interpret and verify signals measured in the noble gas measurement systems in the International Monitoring of the Comprehensive Nuclear-Test-Ban Treaty.

Saey, Paul R.; Bowyer, Ted W.; Ringbom, Anders

2010-09-09T23:59:59.000Z

186

Isotope shift in the sulfur electron affinity: Observation and theory  

SciTech Connect (OSTI)

The sulfur electron affinities {sup e}A(S) are measured by photodetachment microscopy for the two isotopes {sup 32}S and {sup 34}S (16 752.975 3(41) and 16 752.977 6(85) cm{sup -1}, respectively). The isotope shift in the electron affinity is found to be more probably positive, {sup e}A({sup 34}S)- {sup e}A({sup 32}S) =+0.0023(70) cm{sup -1}, but the uncertainty allows for the possibility that it may be either ''normal''[{sup e}A({sup 34}S) > {sup e}A({sup 32}S)] or ''anomalous''[{sup e}A({sup 34}S) < {sup e}A({sup 32}S)]. The isotope shift is estimated theoretically using elaborate correlation models, monitoring the electron affinity and the mass polarization term expectation value. The theoretical analysis predicts a very large specific mass shift (SMS) that counterbalances the normal mass shift (NMS) and produces an anomalous isotope shift {sup e}A({sup 34}S)- {sup e}A({sup 32}S) =-0.0053(24) cm{sup -1}, field shift corrections included. The total isotope shift can always be written as the sum of the NMS (here +0.0169 cm{sup -1}) and a residual isotope shift (RIS). Since the NMS has nearly no uncertainty, the comparison between experimental and theoretical RIS is more fair. With respective values of -0.0146(70) cm{sup -1} and -0.0222(24) cm{sup -1}, these residual isotope shifts are found to agree within the estimated uncertainties.

Carette, Thomas; Scharf, Oliver; Godefroid, Michel [Chimie Quantique et Photophysique, Universite Libre de Bruxelles - CP160/09, B-1050 Brussels (Belgium); Drag, Cyril; Blondel, Christophe; Delsart, Christian [Laboratoire Aime-Cotton, CNRS, Universite Paris-sud, F-91405 Orsay cedex (France); Froese Fischer, Charlotte [National Institute of Standards and Technology Gaithersburg, Maryland 20899-8420 (United States)

2010-04-15T23:59:59.000Z

187

Determination of boron in nuclear materials by isotope dilution technique. Part I  

Science Journals Connector (OSTI)

The application of the mass-spectrometric stable-isotope dilution technique for the determination of microgram and submicrogram quantities of boron in nuclear materials is described. An adequate...10B) is added t...

J. Marsel; D. Milivojevi?

1971-01-01T23:59:59.000Z

188

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

E-Print Network [OSTI]

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 ...

McLean, Noah Morgan

189

Size-specific opal-bound nitrogen isotope measurements in North Pacific sediments  

E-Print Network [OSTI]

sonication, and these samples also showed a d15 Ndb decrease with increasing size. Simple isotope mass-balance calculations of Holocene Ber- ing Sea sediments indicate that most of the d15 Ndb variations among the larger

Gilli, Adrian

190

A direct and rapid leaf water extraction method for isotopic analysis  

E-Print Network [OSTI]

balance calculation to account for the isotopic dilution from the addition of O present in the added CO2 under strictly controlled conditions to conserve accuracy. These methods require a subsequent mass

Yakir, Dan

191

Kinetics of Precursor Labeling in Stable Isotope Labeling in Cell Cultures (SILAC) Experiments  

Science Journals Connector (OSTI)

Recent advances in mass spectrometry have enabled proteome-wide analyses of cellular protein turnover. These studies have been greatly propelled by the development of stable isotope labeling in cell cultures (SILAC), a set of standardized protocols, ...

Tian Zhang; John C. Price; Eslam Nouri-Nigjeh; Jun Li; Marc K. Hellerstein; Jun Qu; Sina Ghaemmaghami

2014-10-09T23:59:59.000Z

192

Isotope effect on the superfluid density in conventional and high-temperature superconductors  

E-Print Network [OSTI]

We investigate the isotope effect on the London penetration depth of a superconductor which measures nS/m* [n subscript s / m superscript asterisk], the ratio of superfluid density to effective mass. We use a simplified ...

Serbyn, Maksym

193

Characterization of uranium isotopic abundances in depleted uranium metal assay standard 115  

Science Journals Connector (OSTI)

Certified reference material (CRM) 115, Uranium (Depleted) Metal (Uranium Assay Standard), was analyzed using a ... TRITON Thermal Ionization Mass Spectrometer to characterize the uranium isotope-amount ratios. T...

K. J. Mathew; G. L. Singleton; R. M. Essex…

2013-04-01T23:59:59.000Z

194

Molecular isotopic effects on coupled electronic and nuclear fluxes  

SciTech Connect (OSTI)

A full quantum treatment shows that coupled electronic and nuclear fluxes exhibit a strong sensitivity to a small mass change in a vibrating molecule. This has been exemplified with the existing isotopes of H{sub 2}{sup +} as well as few fictitious ones. We find that the fluxes undergo a significant change as one goes from one isotope of reduced mass {mu} to another. Other well-defined observables are likewise affected. It turns out that as a general rule, the heavier the isotope, the larger the flux, the smaller the dispersion, and the longer the revival period. While we were able to confirm analytically that the time at the first turning point scales as {radical}({mu}) and that the revival period changes linearly with {mu}, the mechanism of other observables remains subtle as the result of quantum interference highlighted by the pronounced difference observed on the dispersion pattern.

Kenfack, A.; Paulus, B. [Physikalische und Theoretische Chemie, Institut fuer Chemie und Biochemie, Freie Universitaet Berlin, D-14195 Berlin (Germany); Barth, I. [Physikalische und Theoretische Chemie, Institut fuer Chemie und Biochemie, Freie Universitaet Berlin, D-14195 Berlin (Germany); Max-Born-Institut, Max-Born-Strasse 2A, D-12489 Berlin (Germany); Marquardt, F. [Visualisierung und Datenanalyse, Zuse Institut Berlin, D-14195 Berlin (Germany); Fachbereich Mathematik, Freie Universitaet Berlin, D-14195 Berlin (Germany)

2010-12-15T23:59:59.000Z

195

High-Precision Measurements of [superscript 33]S and [superscript 34]S Fractionation during SO[subscript 2] Oxidation Reveal Causes of Seasonality in SO[subscript 2] and Sulfate Isotopic Composition  

E-Print Network [OSTI]

This study presents high-precision isotope ratio-mass spectrometric measurements of isotopic fractionation during oxidation of SO[subscript 2] by OH radicals in the gas phase and H[subscript 2]O[subscript 2] and transition ...

Harris, Eliza

196

Isotopic Abundance of Carbon in Primary Cosmic Rays  

Science Journals Connector (OSTI)

......the usual technique for mass determination is not applicable. But the difference...in which incident 12C turns into boron isotopes and that cross section a-C3C...in which a carbon nucleus or a boron nucleus emerges respectively......

Hiroichi Hasegawa; Kensai Ito

1961-09-01T23:59:59.000Z

197

The New Element Curium (Atomic Number 96)  

DOE R&D Accomplishments [OSTI]

Two isotopes of the element with atomic number 96 have been produced by the helium-ion bombardment of plutonium. The name curium, symbol Cm, is proposed for element 96. The chemical experiments indicate that the most stable oxidation state of curium is the III state.

Seaborg, G. T.; James, R. A.; Ghiorso, A.

1948-00-00T23:59:59.000Z

198

Oak Ridge Isotope Products and Services - Current and Expected Supply and Demand  

SciTech Connect (OSTI)

Oak Ridge National Laboratory (ORNL) has been a major center of isotope production research, development, and distribution for over 50 years. Currently, the major isotope production activities include (1) the production of transuranium element radioisotopes, including 252 Cf; (2) the production of medical and industrial radioisotopes; (3) maintenance and expansion of the capabilities for production of enriched stable isotopes; and, (4) preparation of a wide range of custom-order chemical and physical forms of isotope products, particularly in accelerator physics research. The recent supply of and demand for isotope products and services in these areas, research and development (R&D), and the capabilities for future supply are described in more detail below. The keys to continuing the supply of these important products and services are the maintenance, improvement, and potential expansion of specialized facilities, including (1) the High Flux Isotope Reactor (HFIR), (2) the Radiochemical Engineering Development Center (REDC) and Radiochemical Development Laboratory (RDL) hot cell facilities, (3) the electromagnetic calutron mass separators and the plasma separation process equipment for isotope enrichment, and (4) the Isotope Research Materials Laboratory (IRML) equipment for preparation of specialized chemical and physical forms of isotope products. The status and plans for these ORNL isotope production facilities are also described below.

Aaron, W.S.; Alexander, C.W.; Cline, R.L.; Collins, E.D.; Klein, J.A.; Knauer, J.B., Jr.; Mirzadeh, S.

1999-08-29T23:59:59.000Z

199

Neutron halos in the Na isotopes  

Science Journals Connector (OSTI)

The neutron and proton density distributions of the Na isotopes out to the proton and neutron drip lines are calculated in the spherical Hartree-Fock model with a wide variety of density-dependent Skyrme interactions. The results are compared to recent experimental data for the interaction cross sections and for the rms radii. We discuss the role of the deformed intruder states and the problems associated with predicting the location of the neutron drip line for this mass region. © 1996 The American Physical Society.

B. A. Brown and W. A. Richter

1996-08-01T23:59:59.000Z

200

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

E-Print Network [OSTI]

have come to the forefront as a possible storage medium for hydrogen for fuel-cell de- vices. A number of isotopically substituted hydrogen molecules adsorbed into single-walled car- bon nanotubes are calculated usingContribution of restricted rotors to quantum sieving of hydrogen isotopes B. C. Hathorn,1 B. G

Hathorn, Bryan C.

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Microscopic description of fission in Uranium isotopes with the Gogny energy density functional  

E-Print Network [OSTI]

The most recent parametrizations D1S, D1N and D1M of the Gogny energy density functional are used to describe fission in the isotopes $^{232-280}$ U. Fission paths, collective masses and zero point quantum corrections, obtained within the constrained Hartree-Fock-Bogoliubov approximation, are used to compute the systematics of the spontaneous fission half-lives $t_\\mathrm{SF}$, the masses and charges of the fission fragments as well as their intrinsic shapes. The Gogny-D1M parametrization has been benchmarked against available experimental data on inner and second barrier heights, excitation energies of the fission isomers and half-lives in a selected set of Pu, Cm, Cf, Fm, No, Rf, Sg, Hs and Fl nuclei. It is concluded that D1M represents a reasonable starting point to describe fission in heavy and superheavy nuclei. Special attention is also paid to understand the uncertainties in the predicted $t_\\mathrm{SF}$ values arising from the different building blocks entering the standard semi-classical Wentzel-Kramers-Brillouin formula. Although the uncertainties are large, the trend with mass or neutron numbers are well reproduced and therefore the theory still has predictive power. In this respect, it is also shown that modifications of a few per cent in the pairing strength can have a significant impact on the collective masses leading to uncertainties in the $t_\\mathrm{SF}$ values of several orders of magnitude.

R. Rodriguez-Guzman; L. M. Robledo

2014-05-25T23:59:59.000Z

202

The New Element Berkelium (Atomic Number 97)  

DOE R&D Accomplishments [OSTI]

An isotope of the element with atomic number 97 has been discovered as a product of the helium-ion bombardment of americium. The name berkelium, symbol Bk, is proposed for element 97. The chemical separation of element 97 from the target material and other reaction products was made by combinations of precipitation and ion exchange adsorption methods making use of its anticipated (III) and (IV) oxidation states and its position as a member of the actinide transition series. The distinctive chemical properties made use of in its separation and the equally distinctive decay properties of the particular isotope constitute the principal evidence for the new element.

Seaborg, G. T.; Thompson, S. G.; Ghiorso, A.

1950-04-26T23:59:59.000Z

203

Comparisons between stable isotope tr  

Science Journals Connector (OSTI)

Nitrogen spiraling in streams: Comparisons between stable isotope tracer and nutrient addition experiments. Abstract—A common method to quantify stream.

2007-05-31T23:59:59.000Z

204

Case Number:  

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

Name of Petitioner: Name of Petitioner: Date of Filing: Case Number: Department of Energy Washington, DC 20585 JUL 2 2 2009 DEPARTMENT OF ENERGY OFFICE OF HEARINGS AND APPEALS Appeal Dean P. Dennis March 2, 2009 TBA-0072 Dean D. Dennis filed a complaint of retaliation under the Department of Energy (DOE) Contractor Employee Protection Program, 10 C.F.R. Part 708. Mr. Dennis alleged that he engaged in protected activity and that his employer, National Security Technologies, LLC (NSTec ), subsequently terminated him. An Office of Hearings and Appeals (OHA) Hearing Officer denied relief in Dean P. Dennis, Case No. TBH-0072, 1 and Mr. Dennis filed the instant appeal. As discussed below, the appeal is denied. I. Background The DOE established its Contractor Employee Protection Program to "safeguard public

205

JOB NUMBER  

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

. . . . . . . . . .: LEAVE BLANK (NARA use only) JOB NUMBER N/-&*W- 9d - 3 DATE RECEIVED " -1s - 9 J - NOTIFICATION TOAGENCY , In accordance with the provisions of 44 U.S.C. 3303a the disposition request. including amendments, is ap roved except , . l for items that may be marke,, ,"dis osition not approved" or "withdrawn in c o i m n 10. 4. NAME OF PERSON WITH WHOM TO CONFER 5 TELEPHONE Jannie Kindred (202) 5&-333 5 - 2 -96 6 AGENCYCERTIFICATION -. ~ - I hereby certify that I am authorized to act for this agency in matters pertaining to the disposition of its records and that the records roposed for disposal are not now needed for the business of this agency or wiRnot be needed after t G t r & s s d ; and that written concurrence from

206

KPA Number  

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

Supports CMM-SW Level 3 Supports CMM-SW Level 3 Mapping of the DOE Information Systems Engineering Methodology to the Software Engineering Institute (SEI) Software Capability Maturity Model (CMM-SW) level 3. Date: September 2002 Page 1 KPA Number KPA Activity SEM Section SEM Work Product SQSE Web site http://cio.doe.gov/sqse ORGANIZATION PROCESS FOCUS OPF-1 The software process is assessed periodically, and action plans are developed to address the assessment findings. Chapter 1 * Organizational Process Management * Process Improvement Action Plan * Methodologies ! DOE Methodologies ! SEM OPF-2 The organization develops and maintains a plan for its software process development and improvement activities. Chapter 1 * Organizational Process Management * Process Improvement

207

Parity violating radiative emission of neutrino pair in heavy alkaline earth atoms of even isotopes  

E-Print Network [OSTI]

Metastable excited states ${}^3P_2, {}^3P_0$ of heavy alkaline earth atoms of even isotopes are studied for parity violating (PV) effects in radiative emission of neutrino pair (RENP). PV terms arise from interference between two diagrams containing neutrino pair emission of valence spin current and nuclear electroweak charge density proportional to the number of neutrons in nucleus. This mechanism gives large PV effects, since it does not suffer from the suppression of 1/(electron mass) usually present for non-relativistic atomic electrons. A controllable magnetic field is crucial to identify RENP process by measuring PV observables. Results of PV asymmetries under the magnetic field reversal and the photon circular polarization reversal are presented for an example of Yb atom.

M. Yoshimura; N. Sasao; S. Uetake

2014-03-26T23:59:59.000Z

208

RADIOCHEMICAL STUDIES OF NEUTRON DEFICIENT ACTINIDE ISOTOPES  

E-Print Network [OSTI]

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.

Williams, Kimberly Eve

2011-01-01T23:59:59.000Z

209

Millennial-scale isotope records from a wide-ranging predator show evidence of recent human impact to oceanic food webs  

Science Journals Connector (OSTI)

...Point. Stable Isotope and Accelerator Mass Spectrometry Radiocarbon...and dried at 25 °C in a vacuum oven. Stable isotope data were...CO 2 , and graphitized for Accelerator Mass Spectrometry (AMS) dating...before the age of atmospheric nuclear bomb testing. All radiocarbon...

Anne E. Wiley; Peggy H. Ostrom; Andreanna J. Welch; Robert C. Fleischer; Hasand Gandhi; John R. Southon; Thomas W. Stafford; Jr.; Jay F. Penniman; Darcy Hu; Fern P. Duvall; Helen F. James

2013-01-01T23:59:59.000Z

210

Advanced isotope separation  

SciTech Connect (OSTI)

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.

Not Available

1982-05-04T23:59:59.000Z

211

Isotope Development & Production | Nuclear Science | ORNL  

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

of the "Calutrons" (electromagnetic enrichment devices) were converted by ORNL to the separation and enrichment of stable isotopes and some actinide isotopes. Until 1998 when...

212

Nuclear Masses in Astrophysics  

E-Print Network [OSTI]

Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of N and Z and the data obtained apply to a variety of physics topics. One of the most crucial questions to be addressed in mass spectrometry of unstable radionuclides is the one of understanding the processes of element formation in the Universe. To this end, accurate atomic mass values of a large number of exotic nuclei participating in nucleosynthesis are among the key input data in large-scale reaction network calculations. In this paper, a review on the latest achievements in mass spectrometry for nuclear astrophysics is given.

Christine Weber; Klaus Blaum; Hendrik Schatz

2008-12-09T23:59:59.000Z

213

Synthesis of a new element with atomic number Z=117  

SciTech Connect (OSTI)

The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes 293117 and 294117 were produced in fusion reactions between 48Ca and 249Bk. Decay chains involving eleven new nuclei were identified by means of the Dubna Gas Filled Recoil Separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z111, validating the concept of the long sought island of enhanced stability for super-heavy nuclei.

Oganessian, Yuri Ts. [FLNR-JINR, Russia; Abdullin, F. Sh. [Joint Institute for Nuclear Research, Dubna, Russia; Bailey, P. D. [Oak Ridge National Laboratory (ORNL); Benker, D. E. [Oak Ridge National Laboratory (ORNL); Bennett, M. E. [University of Nevada, Las Vegas; Dmitriev, S. [FLNR-JINR, Russia; Ezold, Julie G. [Oak Ridge National Laboratory (ORNL); Hamilton, J. H. [Vanderbilt University; Henderson, R. [Lawrence Livermore National Laboratory (LLNL); Itkis, M. G. [FLNR-JINR, Russia; Lobanov, Yu. V. [Joint Institute for Nuclear Research, Dubna, Russia; Mezentsev, A. N. [Joint Institute for Nuclear Research, Dubna, Russia; Moody, K. [Lawrence Livermore National Laboratory (LLNL); Nelson, S. L. [Lawrence Livermore National Laboratory (LLNL); Polyakov, A. N. [Joint Institute for Nuclear Research, Dubna, Russia; Porter, C. E. [Oak Ridge National Laboratory (ORNL); Ramayya, A. V. [Vanderbilt University; Riley, F. D. [Oak Ridge National Laboratory (ORNL); Roberto, James B [ORNL; Ryabinin, M. A. [Research Institute of Atomic Reactors, Dimitrovgrad, Russia; Rykaczewski, Krzysztof Piotr [ORNL; Sagaidak, R. N. [Joint Institute for Nuclear Research, Dubna, Russia; Shaughnessy, D. [Lawrence Livermore National Laboratory (LLNL); Shirokovsky, I. V. [Joint Institute for Nuclear Research, Dubna, Russia; Stoyer, M. [Lawrence Livermore National Laboratory (LLNL); Subbotin, V. G. [Joint Institute for Nuclear Research, Dubna, Russia; Sudowe, R. [University of Nevada, Las Vegas; Sukhov, A. M. [Joint Institute for Nuclear Research, Dubna, Russia; Tsyganov, Yu. S. [Joint Institute for Nuclear Research, Dubna, Russia; Utyonkov, V. [FLNR-JINR, Russia; Voinov, A. A. [Joint Institute for Nuclear Research, Dubna, Russia; Vostokin, G. K. [Joint Institute for Nuclear Research, Dubna, Russia; Wilk, P. A. [Lawrence Livermore National Laboratory (LLNL)

2010-01-01T23:59:59.000Z

214

On the Origin of the Lightest Molybdenum Isotopes  

SciTech Connect (OSTI)

We discuss implications of recent precision measurements for the {sup 93}Rh 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 {sup 92}Mo and {sup 94}Mo is set by a competition governed by the proton separation energy of {sup 93}Rh. 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 {sup 92}Mo to {sup 94}Mo 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.

Fisker, J L; Hoffman, R D; Pruet, J

2007-10-24T23:59:59.000Z

215

Advancement of isotope separation for the production of reference standards  

SciTech Connect (OSTI)

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

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

2012-03-01T23:59:59.000Z

216

Ab Initio Nuclear Structure and Reaction Calculations for Rare Isotopes  

SciTech Connect (OSTI)

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).

Draayer, Jerry P [Louisiana State University

2014-09-28T23:59:59.000Z

217

Development of high through-put Sr isotope analysis for monitoring reservoir integrity for CO{sub 2} storage.  

SciTech Connect (OSTI)

Recent innovations in multi-collector ICP-mass spectrometry (MC-ICP-MS) have allowed for rapid and precise measurements of isotope ratios in geological samples. Naturally occurring Sr isotopes has the potential for use in Monitoring, Verification, and Accounting (MVA) associated with geologic CO2 storage. Sr isotopes can be useful for: Sensitive tracking of brine migration; Determining seal rock leakage; Studying fluid/rock reactions. We have optimized separation chemistry procedures that will allow operators to prepare samples for Sr isotope analysis off site using rapid, low cost methods.

Wall, Andy; Jain, Jinesh; Stewart, Brian; Capo, Rosemary; Hakala, Alexandra J.; Hammack, Richard; Guthrie, George

2012-01-01T23:59:59.000Z

218

Apparatus and process for separating hydrogen isotopes  

DOE Patents [OSTI]

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.

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

2013-06-25T23:59:59.000Z

219

Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (White, Et Al.,  

Open Energy Info (EERE)

Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (White, Et Al., Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (White, Et Al., 1992) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Valles Caldera - Redondo Area (White, Et Al., 1992) Exploration Activity Details Location Valles Caldera - Redondo Area Exploration Technique Isotopic Analysis- Fluid Activity Date Usefulness not indicated DOE-funding Unknown Notes Used various geochemical techniques to obtain data from which information regarding mass transfer rates. This then led to conclucions of the history/evolution of the geothermal system. Unclear whether useful for exploration purposes. References Art F. White, Nancy J. Chuma, Fraser Goff (1992) Mass Transfer Constraints On The Chemical Evolution Of An Active Hydrothermal System,

220

Determination of boron isotope ratios by Zeeman effect background correction-graphite furnace atomic absorption spectrometry  

Science Journals Connector (OSTI)

A new method for the determination of isotopic ratio of boron using Zeeman effect background correction-graphite furnace atomic absorption spectrometry with conventional atomizer and natural-boron hollow cathode source is described. The isotope-shift Zeeman effect at 208.9 nm is utilized for isotopic ratio determination. At a given concentration of total boron, the net absorbance decreases linearly with increasing 10B/11B ratio. The absorbances are recorded at the field strength of 1.0 T. The isotope ratios measured by the proposed method were in good agreement with the results obtained by inductively coupled plasma-quadruple mass spectrometry or thermal ionization mass spectrometry. The present method is fairly fast and less expensive compared to the above techniques and is quite suitable for plant environments.

S. Thangavel; S.V. Rao; K. Dash; J. Arunachalam

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

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

E-Print Network [OSTI]

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.

V. Somà; A. Cipollone; C. Barbieri; P. Navrátil; T. Duguet

2013-12-07T23:59:59.000Z

222

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

E-Print Network [OSTI]

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.

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

2010-12-22T23:59:59.000Z

223

Vibrational Dynamics of Isotopically Dilute Nitrogen to 104 GPa  

Science Journals Connector (OSTI)

Raman studies to 104 GPa of a 14N2 host with dilute 15N2 and 14N15N isotopic species indicate an increase in vibrational coupling with pressure. The lowest frequency branch of the isotopic species 15N2 reaches a plateau around 100 GPa suggesting the onset of bond weakening for molecules located on particular sites. An unusual intensity increase is observed for the isotopic ?1 guest modes. The phase transitions above 20 GPa appear to involve an increase in the number of inequivalent sites, with possibly subtle changes in the orientational behavior of particular molecules in the pressure range 25 to 50 GPa not readily revealed in recent x-ray diffraction studies.

H. Olijnyk and A. P. Jephcoat

1999-07-12T23:59:59.000Z

224

METHOD TO TEST ISOTOPIC SEPARATION EFFICIENCY OF PALLADIUM PACKED COLUMNS  

SciTech Connect (OSTI)

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.

Heung, L; Gregory Staack, G; James Klein, J; William Jacobs, W

2007-06-27T23:59:59.000Z

225

First decay study of the very neutron-rich isotope 93Br  

Science Journals Connector (OSTI)

The decay of the mass-separated, very neutron-rich isotope 93Br has been studied by ? spectroscopy. A level scheme of its daughter 93Kr has been constructed. Level energies, ?-ray branching ratios, and multipolarities suggest spins and parities which are in accord with a smooth systematics of the N=57 isotones for Z<~40, suggesting the N=56 subshell closure still to be effective in Kr isotopes. So far, there is no indication of a progressive onset of deformation in neutron-rich Kr isotopes.

G. Lhersonneau; A. Wöhr; B. Pfeiffer; K.-L. Kratz; the ISOLDE Collaboration

2001-02-20T23:59:59.000Z

226

Novel hybrid isotope separation scheme and apparatus  

DOE Patents [OSTI]

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.

Maya, J.

1991-06-18T23:59:59.000Z

227

Novel hybrid isotope separation scheme and apparatus  

DOE Patents [OSTI]

A method of 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.

Maya, Jakob (Brookline, MA)

1991-01-01T23:59:59.000Z

228

Nuclear Charge Radii of Neutron-Deficient Lead Isotopes Beyond N=104 Midshell Investigated by In-Source Laser Spectroscopy  

Science Journals Connector (OSTI)

The shape of exotic even-mass Pb182–190 isotopes was probed by measurement of optical isotope shifts providing mean square charge radii (??r2?). The experiment was carried out at the isolde (cern) on-line mass separator, using in-source laser spectroscopy. Small deviations from the spherical droplet model are observed, but when compared to model calculations, those are explained by high sensitivity of ??r2? to beyond mean-field correlations and small admixtures of intruder configurations in the ground state. The data support the predominantly spherical shape of the ground state of the proton-magic Z=82 lead isotopes near neutron midshell (N=104).

H. De Witte et al.

2007-03-16T23:59:59.000Z

229

Collective potential energy surfaces of light mass Kr isotopes  

Science Journals Connector (OSTI)

Collective potential energy surface calculations have been performed for Kr74-80 nuclei in the framework of the Gneuss and Greiner model. The collective Hamiltonian is diagonalized in the basis of the five-dimensional quadrupole oscillator. Our calculations suggest that the Kr78,80 nuclei are ? unstable with a triaxial minimum at ??40°. The Kr74,76 nuclei have two axially symmetric minima with the 01+ ground state being located mainly in the deformed minimum, whereas the first excited 02+ state is located in the spherical minimum. The calculations also indicate that the ground state wave function for Kr74 is spread over both the minima.[NUCLEAR STRUCTURE Kr74,76,78,80: Calculated potential energy surfaces; compared with experimental energy levels and B(E2) values.

M. Seiwert; A. V. Ramayya; J. Maruhn

1984-01-01T23:59:59.000Z

230

W Transverse Mass  

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

Some Data Analysis Some Data Analysis The Tevatron produces millions of collisions each second in CDF and DZero. The detectors have hardware triggers to decide if a collision is "interesting," that is it contains a candidate event for any one of a number studies. Our dataset contains 48,844 candidate events for a W mass study. There are other datasets to study Z mass, top and b quarks, QCD, etc. Why don't all the W decays give exactly the same mass? Are all these candidates really Ws? What if we chose only some of these data. How would our choice effect the value of the transverse mass? Work with your classmates. Test the data to see what you can learn. Help with data analysis. Record the best estimate of the W transverse mass from your data analysis. Explain which data you used and why. Check with your classmates and explain any differences between your estimate and theirs.

231

ZIRCONIUM—HAFNIUM ISOTOPE EVIDENCE FROM METEORITES FOR THE DECOUPLED SYNTHESIS OF LIGHT AND HEAVY NEUTRON-RICH NUCLEI  

SciTech Connect (OSTI)

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.

Akram, W.; Schönbächler, M. [School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Sprung, P. [Institut für Planetologie, Universität Münster, Wilhelm-Klemm-Strasse 10, D-48149 Münster (Germany); Vogel, N. [Institute for Geochemistry and Petrology, ETH, Clausiusstrasse 25, 8092 Zürich (Switzerland)

2013-11-10T23:59:59.000Z

232

Automated data extraction from in situ protein stable isotope...  

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

data extraction from in situ protein stable isotope probing studies. Automated data extraction from in situ protein stable isotope probing studies. Abstract: Protein stable isotope...

233

Copper isotope fractionation in acid mine drainage. | EMSL  

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

Copper isotope fractionation in acid mine drainage. Copper isotope fractionation in acid mine drainage. Abstract: We surveyed the Cu isotopic composition of primary minerals and...

234

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...

235

Evolution of isotopic composition of reprocessed uranium during the multiple recycling in light water reactors with natural uranium feed  

SciTech Connect (OSTI)

A complex approach based on the consistent modeling of neutron-physics processes and processes of cascade separation of isotopes is applied for analyzing physical problems of the multiple usage of reprocessed uranium in the fuel cycle of light water reactors. A number of scenarios of multiple recycling of reprocessed uranium in light water reactors are considered. In the process, an excess absorption of neutrons by the {sup 236}U isotope is compensated by re-enrichment in the {sup 235}U isotope. Specific consumptions of natural uranium for re-enrichment of the reprocessed uranium depending on the content of the {sup 232}U isotope are obtained.

Smirnov, A. Yu., E-mail: a.y.smirnoff@rambler.ru; Sulaberidze, G. A. [National Research Nuclear University MEPhI (Russian Federation); Alekseev, P. N.; Dudnikov, A. A.; Nevinitsa, V. A., E-mail: neva@dhtp.kiae.ru; Proselkov, V. N.; Chibinyaev, A. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

2012-12-15T23:59:59.000Z

236

Toward laser ablation Accelerator Mass Spectrometry of actinides  

SciTech Connect (OSTI)

A project to measure neutron capture cross sections of a number of actinides in a reactor environment by Accelerator Mass Spectrometry (AMS) at the ATLAS facility of Argonne National Laboratory is underway. This project will require the precise and accurate measurement of produced actinide isotopes in many (>30) samples irradiated in the Advanced Test Reactor at Idaho National Laboratory with neutron fluxes having different energy distributions. The AMS technique at ATLAS is based on production of highlycharged positive ions in an electron cyclotron resonance (ECR) ion source followed by acceleration in the ATLAS linac and mass-to-charge (m/q) measurement at the focus of the Fragment Mass Analyzer. Laser ablation was selected as the method of feeding the actinide material into the ion source because we expect it will have higher efficiency and lower chamber contamination than either the oven or sputtering techniques, because of a much narrower angular distribution of emitted material. In addition, a new multi-sample holder/changer to allow quick change between samples and a computer-controlled routine allowing fast tuning of the accelerator for different beams, are being developed. An initial test run studying backgrounds, detector response, and accelerator scaling repeatability was conducted in December 2010. The project design, schedule, and results of the initial test run to study backgrounds are discussed.

R. C. Pardo; F. G. Kondev; S. Kondrashev; C. Nair; T. Palchan; R. Scott; D. Seweryniak; R. Vondrasek; M. Paul; P. Collon; C. Deibel; M. Salvatores; G. Palmiotti; J. Berg; J. Fonnesbeck; G. Imel

2013-01-01T23:59:59.000Z

237

Hexadecapole shape change in ytterbium isotopes  

Science Journals Connector (OSTI)

In Hartree-Fock calcualtions using nonrelativistic and relativistic models we see a change in sign from positive to negative of the hexadecapole moment with mass number around A=170. Analysis of Hartree-Fock orbitals shows that a group of neutron orbits with large negative hexadecapole moments occur together at the Fermi surface near N=100 and are responsible for the shape change.

S. K. Patra, S. Yoshida, N. Takigawa, C. R. Praharaj, and A. K. Rath

1995-04-01T23:59:59.000Z

238

Special Application Thermoelectric Micro Isotope Power Sources  

SciTech Connect (OSTI)

Promising design concepts for milliwatt (mW) size micro isotope power sources (MIPS) are being sought for use in various space and terrestrial applications, including a multitude of future NASA scientific missions and a range of military applications. To date, the radioisotope power sources (RPS) used on various space and terrestrial programs have provided power levels ranging from one-half to several hundred watts. In recent years, the increased use of smaller spacecraft and planned new scientific space missions by NASA, special terrestrial and military applications suggest the need for lower power, including mW level, radioisotope power sources. These power sources have the potential to enable such applications as long-lived meteorological or seismological stations distributed across planetary surfaces, surface probes, deep space micro-spacecraft and sub-satellites, terrestrial sensors, transmitters, and micro-electromechanical systems. The power requirements are in the range of 1 mW to several hundred mW. The primary technical requirements for space applications are long life, high reliability, high specific power, and high power density, and those for some special military uses are very high power density, specific power, reliability, low radiological induced degradation, and very low radiation leakage. Thermoelectric conversion is of particular interest because of its technological maturity and proven reliability. This paper summarizes the thermoelectric, thermal, and radioisotope heat source designs and presents the corresponding performance for a number of mW size thermoelectric micro isotope power sources.

Heshmatpour, Ben; Lieberman, Al; Khayat, Mo; Leanna, Andrew; Dobry, Ted [Teledyne Energy Systems, Incorporated, 10707 Gilroy Road, Hunt Valley, MD 21031 (United States)

2008-01-21T23:59:59.000Z

239

99.996 %{sup 12}C films isotopically enriched and deposited in situ  

SciTech Connect (OSTI)

Ionizing natural abundance carbon dioxide gas, we extract and mass select the ions, depositing thin films isotopically enriched to 99.9961(4) %{sup 12}C as measured by secondary ion mass spectrometry (SIMS). In solid state quantum information, coherence times of nitrogen-vacancy (NV) centers in {sup 12}C enriched diamond exceeding milliseconds demonstrate the viability of NV centers as qubits, motivating improved isotopic enrichment. NV centers in diamond are particularly attractive qubit candidates due to the optical accessibility of the spin states. We present SIMS analysis and cross-sectional scanning electron microscopy of {sup 12}C enriched thin film samples grown with this method.

Dwyer, K. J. [Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20740 (United States) [Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20740 (United States); National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8423 (United States); Pomeroy, J. M.; Simons, D. S. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8423 (United States)] [National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8423 (United States)

2013-06-24T23:59:59.000Z

240

Isotope shift and hyperfine structure studies of the krypton ion and the thallium atom  

E-Print Network [OSTI]

isotopes of Kr II. TABLE I. Compilation of the Natural Abundances and the Masses of the Krypton Isotopes A N 78 42 80 44 82 46 83 47 84 48 86 50 Abundance(%) 0. 35 2. 25 11. 6 11. 5 57. 0 17, 3 Mass(amu) 77. 920397 79. 916375 81. 913483... does not need to be considered in the error analysis since it leads only to a broadening but not to s. shift of the measured signals. The voltage uncer- tainties are limited by the voltage divider. For 6V/V=10, 6(AV)/ZV=IO 6mr ? 6rns=10 amu and p=0...

Li, Yingfeng

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Heat and Mass Transfer Wrme-und Stoffbertragung  

E-Print Network [OSTI]

1 23 Heat and Mass Transfer Wärme- und Stoffübertragung ISSN 0947-7411 Volume 49 Number 3 Heat Mass

Guo, Zhixiong "James"

242

PLANETARY-SCALE STRONTIUM ISOTOPIC HETEROGENEITY AND THE AGE OF VOLATILE DEPLETION OF EARLY SOLAR SYSTEM MATERIALS  

SciTech Connect (OSTI)

Isotopic anomalies in planetary materials reflect both early solar nebular heterogeneity inherited from presolar stellar sources and processes that generated non-mass-dependent isotopic fractionations. The characterization of isotopic variations in heavy elements among early solar system materials yields important insight into the stellar environment and formation of the solar system, and about initial isotopic ratios relevant to long-term chronological applications. One such heavy element, strontium, is a central element in the geosciences due to wide application of the long-lived {sup 87}Rb-{sup 87}Sr radioactive as a chronometer. We show that the stable isotopes of Sr were heterogeneously distributed at both the mineral scale and the planetary scale in the early solar system, and also that the Sr isotopic heterogeneities correlate with mass-independent oxygen isotope variations, with only CI chondrites plotting outside of this correlation. The correlation implies that most solar system material formed by mixing of at least two isotopically distinct components: a CV-chondrite-like component and an O-chondrite-like component, and possibly a distinct CI-chondrite-like component. The heterogeneous distribution of Sr isotopes may indicate that variations in initial {sup 87}Sr/{sup 86}Sr of early solar system materials reflect isotopic heterogeneity instead of having chronological significance, as interpreted previously. For example, given the differences in {sup 84}Sr/{sup 86}Sr between calcium aluminum inclusions and eucrites ({epsilon}{sup 84}Sr > 2), the difference in age between these materials would be {approx}6 Ma shorter than previously interpreted, placing the Sr chronology in agreement with other long- and short-lived isotope systems, such as U-Pb and Mn-Cr.

Moynier, Frederic; Podosek, Frank A. [Department of Earth and Planetary Science and McDonnell Center for Space Sciences, Washington University, St. Louis, MO 63130 (United States); Day, James M. D. [Geosciences Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093-0244 (United States); Okui, Wataru; Yokoyama, Tetsuya [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Tokyo 152-8551 (Japan); Bouvier, Audrey [Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455-0231 (United States); Walker, Richard J., E-mail: moynier@levee.wustl.edu, E-mail: fap@levee.wustl.edu, E-mail: jmdday@ucsd.edu, E-mail: rjwalker@umd.edu, E-mail: okui.w.aa@m.titech.ac.jp, E-mail: tetsuya.yoko@geo.titech.ac.jp, E-mail: abouvier@umn.edu [Department of Geology, University of Maryland, College Park, MD 20742 (United States)

2012-10-10T23:59:59.000Z

243

Biogeochemical cycling in an organic-rich coastal marine basin. 8. A sulfur isotopic budget balanced by differential diffusion across the sediment-water interface  

SciTech Connect (OSTI)

The sulfur isotopic composition of the sulfur fluxes occurring in the anoxic marine sediments of Cape Lookout Bight, N.C., U.S.A., was determined, and the result of isotopic mass balance was obtained via the differential diffusion model. Seasonal pore water sulfate delta/sup 34/S measurements yielded a calculated sulfate input of 0.6 per thousand. Sulfate transported into the sediments via diffusion appeared to be enriched in the lighter isotope because its concentration gradient was steeper, due to the increase in the measured isotopic composition of sulfate with depth. Similarly, the back diffusion of dissolved sulfide towards the sediment-water interface appeared enriched in the heavier isotope. The isotopic composition of this flux was calculated from measurements of the delta/sup 34/S of dissolved sulfide and was determined to be 15.9 per thousand. The isotopic composition of buried sulfide was determined to be -5.2 per thousand and the detrital sulfur input was estimated to be -6.2 per thousand. An isotope mass balance equation based upon the fluxes at the sediment-water interface successfully predicted the isotopic composition of the buried sulfur flux within 0.5 per thousand, thus confirming that isotopes diffuse in response to their individual concentration gradients.

Chanton, J.P.; Martens, C.S.

1987-05-01T23:59:59.000Z

244

Identification of isotopically primitive interplanetary dust particles: A NanoSIMS isotopic imaging study  

E-Print Network [OSTI]

Identification of isotopically primitive interplanetary dust particles: A NanoSIMS isotopic imaging contain larger regions with more modest enrichments in 15 N, leading to average bulk N isotopic of those IDPs that have anomalous bulk N isotopic compositions. These particles typically also contain

245

Spinelolivine magnesium isotope thermometry in the mantle and implications for the Mg isotopic composition of Earth  

E-Print Network [OSTI]

Spinel­olivine magnesium isotope thermometry in the mantle and implications for the Mg isotopic: magnesium isotopes mantle geochemistry meteorites MC-ICPMS The magnesium isotopic composition of Earth., 2004; Poitrasson et al., 2005; Georg et al., 2007; Poitrasson, 2007; Weyer et al., 2007). Magnesium

Manning, Craig

246

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.

247

Respiration, photosynthesis, and oxygen isotope fractionation in ...  

Science Journals Connector (OSTI)

Jan 25, 1971 ... Respiration, photosynthesis, and oxygen isotope fractionation in oceanic surface water1. Peter M. Kroopnick. Department of Oceanography,.

2000-01-04T23:59:59.000Z

248

Magnesium Isotope Effects in Enzymatic Phosphorylation  

Science Journals Connector (OSTI)

So far as magnesium isotope effect in phosphorylation is an unexpected and unusual phenomenon, it is worthy to shortly describe materials and technologies used in isotopic biochemical experiments. ... Isotope-containing MgCl2 samples were obtained using treatment of magnesium oxides 24MgO, 25MgO, 26MgO, and *MgO with analytically pure HCl (*Mg means magnesium with natural abundance of the three isotopes; see Table 1). ...

Anatoly L. Buchachenko; Dmitry A. Kouznetsov; Natalia N. Breslavskaya; Marina A. Orlova

2008-02-05T23:59:59.000Z

249

Isotope and Ion Selectivity in Reverse Osmosis Desalination: Geochemical Tracers for Man-made Freshwater  

Science Journals Connector (OSTI)

A systematic measurement of ions and 2H/1H, 7Li/6Li, 11B/10B, 18O/16O, and 87Sr/86Sr isotopes in feed-waters, permeates, and brines from commercial reverse osmosis (RO) desalination plants in Israel (Ashkelon, Eilat, and Nitzana) and Cyprus (Larnaca) reveals distinctive geochemical and isotopic fingerprints of fresh water generated from desalination of seawater (SWRO) and brackish water (BWRO). ... The specific geochemical and isotopic fingerprints of SWRO provide a unique tool for tracing “man-made” fresh water as an emerging recharge component of natural water resources. ... O and H isotopes were determined by dual inlet and continuous flow mass spectrometry following gas–water equilibration (analytical uncertainties ±0.8‰ for ?2H and ±0.1‰ for ?18O). ...

Wolfram Kloppmann; Avner Vengosh; Catherine Guerrot; Romain Millot; Irena Pankratov

2008-05-21T23:59:59.000Z

250

Pair-truncated shell-model analysis of nuclei around mass 130  

SciTech Connect (OSTI)

Low-lying states for even-even, odd-mass, and doubly odd nuclei in the mass A{approx}130 region are systematically investigated using a pair-truncated shell model. In this model the collective nucleon pairs with angular momenta zero and two are the basic ingredients for even-even nuclei. Additional unpaired nucleons are added to the even-even core for a description of odd-mass and doubly odd nuclei. The effective interactions consist of single-particle energies and monopole and quadrupole pairing plus quadrupole-quadrupole interactions, whose strengths are assumed to be linearly changed as functions of the number of nucleons so as to describe the level schemes of the even-even and odd-mass nuclei. Energy levels of the low-lying collective states for even-even Xe, Ba, Ce, and Nd isotopes are reproduced very well along with intraband and interband B(E2) values, which simulate the typical features of the O(6) limit of the interacting boson model. For odd-mass and doubly odd nuclei, complicated level schemes and electromagnetic moments are in excellent agreement with the experimental data.

Higashiyama, Koji [Department of Physics, Chiba Institute of Technology, Narashino, Chiba 275-0023 (Japan); Yoshinaga, Naotaka [Department of Physics, Saitama University, Saitama City 338-8570 (Japan)

2011-03-15T23:59:59.000Z

251

Isotope separation with the RICH detector of the AMS Experiment  

E-Print Network [OSTI]

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.

Luísa Arruda; Fernando Barão; João Borges; Fernando Carmo; Patrícia Gonçalves; Rui Pereira; Mário Pimenta

2007-10-03T23:59:59.000Z

252

Proton Radioactivity Measurements at HRIBF: Ho, Lu, and Tm Isotopes  

SciTech Connect (OSTI)

Two new isotopes, {sup 145}Tm and {sup 140}Ho and three isomers in previously known isotopes, {sup 141m}Ho, {sup 150m}Lu and {sup 151m}Lu have been discovered and studied via their decay by proton emission. These proton emitters were produced at the Holifield Radioactive Ion Beam Facility (HRIBF) by heavy-ion fusion-evaporation reactions, separated in A/Q with a recoil mass spectrometer (RMS), and detected in a double-sided silicon strip detector (DSSD). The decay energy and half-life was measured for each new emitter. An analysis in terms of a spherical shell model is applied to the Tm and Lu nuclei, but Ho is considerably deformed and requires a collective model interpretation.

Akovali, Y.; Batchelder, J.C.; Bingham, C.R.; Davinson, T.; Ginter, T.N.; Gross, C.J.; Grzywacz, R.; Hamilton, J.H.; Janas, Z.; Karny, M.; Kim, S.H.; MacDonald, B.D.; Mas, J.F.; McConnell, J.W.; Piechaczek, A.; Ressler, J.J.; Rykaczewski, K.; Slinger, R.C.; Szerypo, J.; Toth, K.S.; Weintraub, W.; Woods, P.J.; Yu, C.-H.; Zganjar, E.F.

1998-11-13T23:59:59.000Z

253

Evolution of Shell Structure in Neutron-Rich Calcium Isotopes  

SciTech Connect (OSTI)

We employ interactions from chiral effective field theory and compute the binding energies and low-lying excitations of calcium isotopes with the coupled-cluster method. Effects of three-nucleon forces are included phenomenologically as in-medium two-nucleon interactions, and the coupling to the particle continuum is taken into account using a Berggren basis. The computed ground-state energies and the low-lying J =2+ states for the isotopes 42,48,50,52Ca are in good agreement with data, and we predict the excitation energy of the first J =2+ state in 54Ca at 1.9 MeV, displaying only a weak subshell closure. In the odd-mass nuclei 53,55,61Ca we find that the positive parity states deviate strongly from the naive shell model.

Hagen, G. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Hjorth-Jensen, M. [NSCL, Michigan State University/ Univ. Oslo, Norway; Jansen, G R [University of Oslo, Norway; Machleidt, R [University of Idaho; Papenbrock, T. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)

2012-01-01T23:59:59.000Z

254

The mass  

Science Journals Connector (OSTI)

The mass of the charged Higgs boson at the 1-loop level is investigated, assuming the CP symmetry to be violated explicitly in the Higgs sector of the minimal supersymmetric standard model (MSSM). It is found that there is a parameter region of the MSSM where the presence of explicit CP violation in the Higgs sector yields negative radiative corrections to the charged Higgs boson mass. Thus, the charged Higgs boson in the MSSM may have as low a mass as 60 GeV at the 1-loop level, if the CP symmetry is violated. This lower bound may be improved by the Higgs search at LEP2, which imposes experimental constraints on the charged Higgs mass, as well as on the masses of the neutral Higgs bosons. Hence, LEP2 can constrain experimentally the charged Higgs mass to be not smaller than 109 GeV under our assumption. In addition, it sets 75 GeV as the lower bound on the mass of the lightest neutral Higgs boson, and 84 GeV for that of the next-to-lightest neutral Higgs boson.

Seung Woo Ham; Sun Kun Oh; Eun Jong Yoo; Hyun Kyu Lee

2001-01-01T23:59:59.000Z

255

Testing atomic mass models with radioactive beams  

SciTech Connect (OSTI)

Significantly increased yields of new or poorly characterized exotic isotopes that lie far from beta-decay stability can be expected when radioactive beams are used to produce these nuclides. Measurements of the masses of these new species are very important. Such measurements are motivated by the general tendency of mass models to diverge from one another upon excursions from the line of beta-stability. Therefore in these regions (where atomic mass data are presently nonexistent or sparse) the models can be tested rigorously to highlight the features that affect the quality of their short-range and long-range extrapolation properties. Selection of systems to study can be guided, in part, by a desire to probe those mass regions where distinctions among mass models are most apparent and where yields of exotic isotopes, produced via radioactive beams, can be optimized. Identification of models in such regions that have good predictive properties will aid materially in guiding the selection of additional experiments which ultimately will provide expansion of the atomic mass database for further refinement of the mass models. 6 refs., 5 figs.

Haustein, P.E.

1989-01-01T23:59:59.000Z

256

Isotope Evidence for Ozone Formation on Surfaces  

Science Journals Connector (OSTI)

Remarkably, the gas-phase recombination or association reaction of ozone has an unusually large (?10%) isotope effect and shows almost equal enrichments of the ozone molecules containing two different oxygen isotopes. ... For a better understanding of the pressure and temperature dependence of ozone isotopic composition in oxygen discharges, we developed a relatively simple isotope kinetic model that accounts for the processes of (i) heterogeneous ozone formation at the reactor walls, (ii) isotope exchange of oxygen atoms with O2 molecules, and (iii) ozone formation in the gas phase. ...

Christof Janssen; Béla Tuzson

2010-05-06T23:59:59.000Z

257

Isotope Effects in Isotope-Exchange Reactions:? Evidence for a Large 12C/13C Kinetic Isotope Effect in the Gas Phase  

Science Journals Connector (OSTI)

Isotope effects are key to understanding reaction mechanisms because isotopic substitution affects reaction rates and equilibrium constants. ... These values are considered in relation to the vapor pressures of isotopic compds., the geologic abundance of C and O isotopes, the relative abundance of O isotopes in air and H2O, and variations in the at. ...

Giulia de Petris; Anna Troiani

2008-03-05T23:59:59.000Z

258

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

SciTech Connect (OSTI)

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

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

2013-01-14T23:59:59.000Z

259

Feasibility study of plutonium isotopic analysis of resin beads by nondestructive gamma-ray spectroscopy  

SciTech Connect (OSTI)

We have initiated a feasibility study on the use of nondestructive low-energy gamma-ray spectroscopy for plutonium isotopic analysis on resin beads. Seven resin bead samples were measured, with each sample containing an average of 9 ..mu..g of plutonium; the isotopic compositions of the samples varied over a wide range. The gamma-ray spectroscopy results, obtained from 4-h counting-time measurements, were compared with mass spectrometry results. The average ratios of gamma-ray spectroscopy to mass spectrometry were 1.014 +- 0.025 for /sup 238/Pu//sup 239/Pu, 0.996 +- 0.018 for /sup 240/Pu//sup 239/Pu, and 0.980 +- 0.038 for /sup 241/Pu//sup 239/Pu. The rapid, automated, and accurate nondestructive isotopic analysis of resin beads may be very useful to process technicians and International Atomic Energy Agency inspectors. 3 refs., 1 fig., 3 tabs.

Li, T.K.

1985-01-01T23:59:59.000Z

260

Application of ion-exchange to mass spectrometric determination of boron in mineral waters  

Science Journals Connector (OSTI)

The mass spectrometric stable isotope dilution technique has been applied to the determination of boron in mineral waters. Highly enriched10B in the form of H3BO3...was added to the mineral water sample as a spik...

B. Gorenc; J. Marsel; G. Tramšek

1970-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Multidetector calibration for mass spectrometers  

SciTech Connect (OSTI)

The International Atomic Energy Agency`s Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (1) peak-shift experiments and (2) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements were made by shifting the isotopes to various Faraday detectors. Two different peak-shifting schemes were used to measure plutonium (UK Pu5/92138) samples. For peak-jump experiments, ion intensities were measured in a reference Faraday detector for a single isotope and compared with those measured in the other Faraday detectors. Repeated measurements were made by switching back-and-forth between the reference Faraday detector and a selected Faraday detector. This switching procedure is repeated for all Faraday detectors. Peak-jump experiments were performed with replicate measurements of {sup 239}Pu, {sup 187}Re, and {sup 238}U. Detector efficiency factors were estimated for both peak-jump and peak-shift experiments using a flexible calibration model to statistically analyze both types of multidetector calibration experiments. Calculated detector efficiency factors were shown to depend on both the material analyzed and the experimental conditions. A single detector efficiency factor is not recommended for each detector that would be used to correct routine sample analyses. An alternative three-run peak-shift sample analysis should be considered. A statistical analysis of the data from this peak-shift experiment can adjust the isotopic ratio estimates for detector differences due to each sample analysis.

Bayne, C.K. [Oak Ridge National Lab., TN (United States); Donohue, D.L.; Fiedler, R. [IAEA, Seibersdorf (Austria). Safeguards Analytical Lab.

1994-06-01T23:59:59.000Z

262

Xlink-Identifier: An Automated Data Analysis Platform for Confident Identifications of Chemically Cross-linked Peptides using Tandem Mass Spectrometry  

SciTech Connect (OSTI)

Chemical cross-linking combined with mass spectrometry provides a powerful method for identifying protein-protein interactions and probing the structure of protein complexes. Cross-linking is the process of covalently joining two proteins using cross-linking reagents. After proteolytic cleavage, the cross-linked peptides can be identified using tandem mass spectrometry. A number of strategies have been reported that take advantage of the high sensitivity and high resolution of modern mass spectrometers. Approaches typically include synthesis of novel cross-linking compounds and/or isotopic labelling of the cross-linkering reagent and/or protein to aid both identification and quantitation. However, these approaches have various limitations. These limitations can be overcome with a label-free approach and application of associated data analysis algorithms described in this work.

Du, Xiuxia; Chowdhury, Saiful M.; Manes, Nathan P.; Wu, Si; Mayer, M. Uljana; Adkins, Joshua N.; Anderson, Gordon A.; Smith, Richard D.

2011-03-04T23:59:59.000Z

263

W Transverse Mass  

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

Transverse Mass Histogram Transverse Mass Histogram Data for 49,844 candidate W events are in an Excel spreadsheet with the following data as shown in the table below: A B C D 1 Run No Event No W TMass GeV/c2 Bins 2 55237 19588 68.71732 3 55237 30799 72.19464 Get the data. Sort the data by ascending mass. Be sure to sort all the data in the first three columns! Make a histogram of the data. Rather than graphing the data as individual points, physicists group the data by mass. They consider the full range of the data and divide it into "bins" of equal range size. A histogram is a graph of the number of events in each bin vs. the bin range. They are looking for a peak in the data where most of the masses fall. This will be the value of the mass as detemined by that dataset, and the width of the distribution is a reflection of the errors in the measurements.

264

Kinetic Isotope Effects in Cycloreversion of Rhenium (V) Diolates  

Science Journals Connector (OSTI)

The isotope effects were all calculated from these ratios according to the equation25 (F = extent of reaction; R = isotopic ratio vs reference at extent of reaction F; R0 = initial isotopic ratio vs reference). ... The magnitudes of small kinetic isotope effects (KIEs) are amplified in the isotopic compn. of starting materials recovered from reactions taken to high conversions. ... The magnitudes of small kinetic isotope effects (KIEs) are amplified in the isotopic compn. of starting materials recovered from reactions taken to high conversions. ...

Kevin P. Gable; Fedor A. Zhuravlev

2002-03-21T23:59:59.000Z

265

Carbon isotope separation by absorptive distillation. [Data between 77. 4 and 114. 3 K; Henry's law behavior  

SciTech Connect (OSTI)

The feasibility of separating carbon isotopes by absorptive distillation has been studied for CO absorption by cryogenic solvents. Phase equilibrium, isotopic separation, and mass transfer data were taken between 77.4 and 114.3 K for the following solvents: propane, propylene, 1:1 propane-propylene, 1-butene, isobutane and nitrogen. Carbon monoxide solubility followed Henry's Law, with a maximum experimental solubility of 6.5 mole per cent. Isotopic separation between CO in the gas and liquid phases using hydrocarbon solvents was several times that for pure CO vapor-liquid equilibrium. The maximum observed isotopic separation factor was 1.029 at 77.4 K with the propane-propylene solvent mixture. Mass transfer measurements yielded calculated HTU's of 2 to 5 cm for a possible separation system. An attempt has been made to correlate isotopic separation data using Hildebrand's theory of solutions. The differential absorption of isotopic CO species is expressed as a difference in solubility of the isotopic CO molecules. Data for propane, propylene, and 1-butene show approximately the same behavior at varying temperatures.

Mills, T.R.

1980-04-01T23:59:59.000Z

266

California GAMA Special Study: An isotopic and dissolved gas investigation of nitrate source and transport to a public supply well in California's Central Valley  

SciTech Connect (OSTI)

This study investigates nitrate contamination of a deep municipal drinking water production well in Ripon, CA to demonstrate the utility of natural groundwater tracers in constraining the sources and transport of nitrate to deep aquifers in the Central Valley. The goal of the study was to investigate the origin (source) of elevated nitrate and the potential for the deep aquifer to attenuate anthropogenic nitrate. The site is ideal for such an investigation. The production well is screened from 165-325 feet below ground surface and a number of nearby shallow and deep monitoring wells were available for sampling. Furthermore, potential sources of nitrate contamination to the well had been identified, including a fertilizer supply plant located approximately 1000 feet to the east and local almond groves. A variety of natural isotopic and dissolved gas tracers including {sup 3}H-{sup 3}He groundwater age and the isotopic composition of nitrate are applied to identify nitrate sources and to characterize nitrate transport. An advanced method for sampling production wells is employed to help identify contaminant contributions from specific screen intervals. Nitrate transport: Groundwater nitrate at this field site is not being actively denitrified. Groundwater parameters indicate oxic conditions, the dissolved gas data shows no evidence for excess nitrogen as the result of denitrification, and nitrate-N and -O isotope compositions do not display patterns typical of denitrification. Contaminant nitrate source: The ambient nitrate concentration in shallow groundwater at the Ripon site ({approx}12 mg/L as nitrate) is typical of shallow groundwaters affected by recharge from agricultural and urban areas. Nitrate concentrations in Ripon City Well 12 (50-58 mg/L as nitrate) are significantly higher than these ambient concentrations, indicating an additional source of anthropogenic nitrate is affecting groundwater in the capture zone of this municipal drinking water well. This study provides two new pieces of evidence that the Ripon Farm Services Plant is the source of elevated nitrate in Ripon City Well 12. (1) Chemical mass balance calculations using nitrate concentration, nitrate isotopic composition, and initial tritium activity all indicate that that the source water for elevated nitrate to Ripon City Well 12 is a very small component of the water produced by City Well 12 and thus must have extremely high nitrate concentration. The high source water nitrate concentration ({approx}1500 mg/L as nitrate) required by these mass balance calculations precludes common sources of nitrate such as irrigated agriculture, dairy wastewater, and septic discharge. Shallow groundwater under the Ripon Farm Services RFS plant does contain extremely high concentrations of nitrate (>1700 mg/L as nitrate). (2) Nitrogen and oxygen isotope compositions of nitrate indicate that the additional anthropogenic nitrate source to Ripon City Well 12 is significantly enriched in {delta}{sup 18}O-NO{sub 3}, an isotopic signature consistent with synthetic nitrate fertilizer, and not with human or animal wastewater discharge (i.e. dairy operations, septic system discharge, or municipal wastewater discharge), or with organic fertilizer. Monitoring wells on and near the RFS plant also have high {delta}{sup 18}O-NO{sub 3}, and the plant has handled and stored synthetic nitrate fertilizer that will have this isotopic signature. The results described here highlight the complexity of attributing nitrate found in long screened, high capacity wells to specific sources. In this case, the presence of a very high concentration source near the well site combined with sampling using multiple isotopic tracer techniques and specialized depth-specific techniques allowed fingerprinting of the source in the mixed-age samples drawn from the production well.

Singleton, M J; Moran, J E; Esser, B K; Roberts, S K; Hillegonds, D J

2010-04-14T23:59:59.000Z

267

Beta-delayed proton emission in neutron-deficient lanthanide isotopes  

SciTech Connect (OSTI)

Forty-two ..beta..-delayed proton precursors with 56less than or equal toZless than or equal to71 and 63less than or equal toNless than or equal to83 were produced in heavy-ion reactions at the Lawrence Berkeley Laboratory SuperHILAC and their radioactive decay properties studied at the on-line mass separation facility OASIS. Twenty-five isotopes and eight delayed proton branches were identified for the first time. Delayed proton energy spectra and proton coincident ..gamma..-ray and x-ray spectra were measured for all precursors. In a few cases, proton branching ratios were also determined. The precursor mass numbers were determined by the separator, while the proton coincident x-ray energies provided unambiguous Z identifications. The proton coincident ..gamma..-ray intensities were used to extract final state branching ratios. Proton emission from ground and isomeric states was observed in many cases. The majority of the delayed proton spectra exhibited the smooth bell-shaped distribution expected for heavy mass precursors. The experimental results were compared to statistical model calculations using standard parameter sets. Calculations using Nilsson model/RPA ..beta..-strength functions were found to reproduce the spectral shapes and branching ratios better than calculations using either constant or gross theory ..beta..-strength functions. Precursor half-life predictions from the Nilsson model/RPA ..beta..-strength functions were also in better agreement with the measured half-lives than were gross theory predictions. The ratios of positron coincident proton intensities to total proton intensities were used to determine Q/sub EC/-B/sub p/ values for several precursors near N=82. The statistical model calculations were not able to reproduce the experimental results for N=81 precursors. 154 refs., 82 figs., 19 tabs.

Wilmarth, P.A.

1988-09-30T23:59:59.000Z

268

Current Direct Neutrino Mass Experiments  

E-Print Network [OSTI]

In this contribution we review the status and perspectives of direct neutrino mass experiments. These experiments investigate the kinematics of $\\beta$-decays of specific isotopes ($^3$H, $^{187}$Re, $^{163}$Ho) to derive model-independent information on the averaged electron (anti-) neutrino mass, which is formed by the incoherent sum of the neutrino mass eigenstates contributing to the electron neutrino. We first review the kinematics of $\\beta$-decay and the determination of the neutrino mass, before giving a brief overview of past neutrino mass measurements (SN1987a-ToF studies, Mainz and Troitsk experiments for $^3$H, cryo-bolometers for $^{187}$Re). We then describe the Karlsruhe Tritium Neutrino (KATRIN) experiment which is currently under construction at Karlsruhe Institute of Technology. The large-scale setup will use the MAC-E-Filter principle pioneered earlier to push the sensitivity down to a value of 200 meV(90% C.L.). KATRIN faces many technological challenges that have to be resolved with regar...

Drexlin, G; Mertens, S; Weinheimer, C

2013-01-01T23:59:59.000Z

269

Fusion reactions with germanium isotopes  

Science Journals Connector (OSTI)

Measurements of the fusion of 16O and 27Al with a series of germanium isotopes are analyzed within a coupled-channels approach. It is found that couplings based interactions that are linear in the deformation amplitudes are insufficient in reproducing the data. In order to obtain reasonable fits, it is necessary also to include couplings based on quadratic interactions. The analysis suggests that the nuclear radius of 72Ge is significantly smaller than predicted from a smooth interpolation between other germanium isotopes. The large prolate deformation of 74Ge, which has been proposed as the preferred solution to measurements of the quadrupole moment of the 2+ state, is not supported by the analysis; the near spherical solution is more likely.

H. Esbensen

2003-09-04T23:59:59.000Z

270

?-decay properties of the new neutron deficient isotope 212Pa  

Science Journals Connector (OSTI)

The new neutron deficient isotope 212Pa has been produced in the 182W(35Cl,5n) reaction at a beam energy of 182.5 MeV. Evaporation residues have been separated with the JAERI recoil mass separator and identified on the basis of time- and position-correlated ?-decay chains. The ? decay from the ground state of 212Pa has been observed with an ?-particle energy of 8.270(30) MeV and a half-life of 5.1-1.9+6.1 ms.

S. Mitsuoka; H. Ikezoe; T. Ikuta; Y. Nagame; K. Tsukada; I. Nishinaka; Y. Oura; Y. L. Zhao

1997-03-01T23:59:59.000Z

271

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

SciTech Connect (OSTI)

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.

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

2013-05-19T23:59:59.000Z

272

Nuclear Energy Protocol for Research Isotopes Owen Lowe  

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

Protocol for Protocol for Research Isotopes Owen Lowe Office of Isotopes for Medicine and Science Office of Nuclear Energy, Science and Technology April 16, 2002 Isotopes for Life Isotopes for Life Isotopes for Life Office of Nuclear Energy, Science and Technology Lowe/April16_02 NEPRI to NERAC.ppt (2) Nuclear Energy Protocol For Research Isotopes Nuclear Energy Protocol For Research Isotopes Why NEPRI? 6 NEPRI implements DOE funding priorities for fiscal year 2003 6 NEPRI will * Bring order to DOE's responses to requests for research isotopes * Introduce a high-quality peer review to the selection of research isotopes * Enable DOE to concentrate on operating its unique isotope production facilities Isotopes for Life Isotopes for Life Isotopes for Life Office of Nuclear Energy, Science and Technology

273

Electromagnetic Isotope Separation Lab (EMIS) | ORNL  

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

Electromagnetic Isotope Separation Lab Electromagnetic Isotope Separation Lab May 30, 2013 ORNL established the Stable Isotope Enrichment Laboratory (SIEL) as part of a project funded by the DOE Office of Science, Nuclear Physics Program to develop a modernized electromagnetic isotope separator (EMIS), optimized for separation of a wide range of stable isotopes. The SIEL is located in the Building 6010 Shield Test Station, space formerly allocated to the Oak Ridge Electron Linear Accelerator, on the main campus of ORNL. ORNL staff have designed and built a nominal 10 mA ion current EMIS (sum of all isotopes at the collector) in the SIEL. This EMIS is currently being tested to determine basic performance metrics such as throughput and enrichment factor per pass. This EMIS unit and space will be used to

274

Rapid scanning mass spectrometer  

SciTech Connect (OSTI)

Mass spectrometers and residual gas analyzers (RGA) are used in a variety of applications for analysis of volatile and semi-volatile materials. Analysis is performed by detecting fragments of gas molecules, based on their mass to charge ratio, which are generated in the mass spectrometer. When used as a detector for a gas chromatograph, they function as a means to quantitatively identify isolated volatile species which have been separated from other species via the gas chromatograph. Vacuum Technology, Inc., (VTI) produces a magnetic sector mass spectrometer/RGA which is used in many industrial and laboratory environments. In order to increase the utility of this instrument, it is desirable to increase the mass scanning speed, thereby increasing the number of applications for which it is suited. This project performed the following three upgrades on the computer interface. (1) A new electrometer was designed and built to process the signal from the detector. This new electrometer is more sensitive, over 10 times faster, and over 100 times more stable than the electrometer it will replace. (2) The controller EPROM was reprogrammed with new firmware. This firmware acts as an operating system for the interface and is used to shuttle communications between the PC and the AEROVAC mass spectrometer. (3) The voltage regulator which causes the ion selector voltage to ramp to allow ions of selected mass to be sequentially detected was redesigned and prototyped. The redesigned voltage regulator can be ramped up or down more than 100 times faster than the existing regulator. These changes were incorporated into a prototype unit and preliminary performance testing conducted. Results indicated that scanning speed was significantly increased over the unmodified version.

Leckey, J.H. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Boeckmann, M.D. [Vacuum Technology, Inc., Oak Ridge, TN (United States)

1996-11-25T23:59:59.000Z

275

Enforcement Letter, International Isotopes Idaho Inc - August...  

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

Isotopes Idaho, Inc. related to the Relocation of an Irradiated Pellet at the Test Reactor Area Hot Cell Facility at the Idaho National Engineering and Environmental...

276

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.

277

Category:Isotope Geothermometry | Open Energy Information  

Open Energy Info (EERE)

Login | Sign Up Search Category Edit History Facebook icon Twitter icon Category:Isotope Geothermometry Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home...

278

Integration of Nontraditional Isotopic Systems Into Reaction...  

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

minerals in geothermal systems (feldspars, epidote, and calcite) often control fracture permeability changes. Measurements of Ca and Sr isotopic fractionation at high...

279

Science with Beams of Radioactive Isotopes  

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

2015 The International Chemical Congress of Pacific Basin Societies Science with Beams of Radioactive Isotopes ( 340) Honolulu, Hawaii, USA December 15-20, 2015 Science...

280

Integration of Nontraditional Isotopic Systems Into Reaction...  

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

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

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

18O-Labeled Proteome Reference as Global Internal Standards for Targeted Quantification by Selected Reaction Monitoring-Mass Spectrometry  

SciTech Connect (OSTI)

Selected reaction monitoring-mass spectrometry (SRM-MS) is an emerging technology for high throughput targeted protein quantification and verification in biological and biomarker discovery studies; however, the cost associated with the use of stable isotope labeled synthetic peptides as internal standards is prohibitive for quantitatively screening large numbers of candidate proteins as often required in the pre-verification phase of biomarker discovery. Herein we present the proof-of-concept experiments of using an 18O-labeled 'universal' reference as comprehensive internal standards for quantitative SRM-MS analysis. With an 18O-labeled whole proteome sample as reference, every peptide of interest will have its own corresponding heavy isotope labeled internal standard, thus providing an ideal approach for quantitative screening of a large number of candidates using SRM-MS. Our results showed that the 18O incorporation efficiency using a recently improved protocol was >99.5% for most peptides investigated, a level comparable to 13C/15N labeled synthetic peptides in terms of heavy isotope incorporation. The accuracy, reproducibility, and linear dynamic range of quantification were further assessed based on known ratios of standard proteins spiked into mouse plasma with an 18O-labeled mouse plasma reference. A dynamic range of four orders of magnitude in relative concentration was obtained with high reproducibility (i.e., coefficient of variance <10%) based on the 16O/18O peak area ratios. Absolute and relative quantification of C-reactive protein and prostate-specific antigen were demonstrated by coupling an 18O-labeled reference with standard additions of protein standards. Collectively, our results demonstrated that the use of 18O-labeled reference provides a convenient and effective strategy for quantitative SRM screening of large number of candidate proteins.

Kim, Jong Seo; Fillmore, Thomas L.; Liu, Tao; Robinson, Errol W.; Hossain, Mahmud; Champion, Boyd L.; Moore, Ronald J.; Camp, David G.; Smith, Richard D.; Qian, Weijun

2011-10-11T23:59:59.000Z

282

Relativistic calculations of the isotope shifts in highly charged Li-like ions  

E-Print Network [OSTI]

Relativistic calculations of the isotope shifts of energy levels in highly charged Li-like ions are performed. The nuclear recoil (mass shift) contributions are calculated by merging the perturbative and large-scale configuration-interaction Dirac-Fock-Sturm (CI-DFS) methods. The nuclear size (field shift) contributions are evaluated by the CI-DFS method including the electron-correlation, Breit, and QED corrections. The nuclear deformation and nuclear polarization corrections to the isotope shifts in Li-like neodymium, thorium, and uranium are also considered. The results of the calculations are compared with the theoretical values obtained with other methods.

Zubova, N A; Shabaev, V M; Tupitsyn, I I; Volotka, A V; Plunien, G; Brandau, C; Stöhlker, Th

2014-01-01T23:59:59.000Z

283

Neutrino mass, lepton number, and the origin of matter  

E-Print Network [OSTI]

antiparticles? And many other things% Do neutrinos violate CP? #12;Neutrinoless Double Beta Decay W. Rodejohann? #12;Neutrinoless Double Beta Decay 1 sigma W. Rodejohann, 1206.2560 #12;14 F. Iachello #12;15 Regions

284

Reexamination of nuclear quadrupole moments in 39?41K isotopes  

Science Journals Connector (OSTI)

Nuclear quadrupole moments (Q's) in three isotopes of the potassium atom (K) with mass numbers 39, 40, and 41 are evaluated more precisely in this work. The Q value of 39K is determined to be 0.0614(6) b by combining the available experimental result of the electric quadrupole hyperfine structure constant (B) with our calculated B/Q result of its 4P3/2 state. Furthermore, combining this Q value with the measured ratios Q(40K)/Q(39K) and Q(41K)/Q(39K), we obtain Q(40K)=?0.0764(8)b and Q(41K)=0.0747(7)b, respectively. These results disagree with the sub-1% accuracy standard values recently quoted by Pyykkö [Mol. Phys. 106, 1965 (2008)]. The calculations were carried out by employing the relativistic coupled-cluster theory at the single, double, and involving important valence triple approximation. The accuracies of the calculated B/Q results can be viewed on the basis of comparison between our calculated magnetic dipole hyperfine structure constants (A's) with their corresponding measurements for many low-lying states. Both A and B results in a few more excited states are presented. Also, we find that the latest reported experimental hyperfine structure constant results for the 4P states in 39K are inconsistent with our calculations.

Yashpal Singh; D. K. Nandy; B. K. Sahoo

2012-09-24T23:59:59.000Z

285

The Mg isotope composition of presolar silicate grains from red giant stars  

Science Journals Connector (OSTI)

Abstract We report O and Mg isotope compositions of presolar silicate grains which likely formed around asymptotic giant branch stars. Our grains represent the most abundant Mg-rich presolar grain group and their Mg isotope composition provides thus far missing information about the contribution of isotopically anomalous presolar dust to the Mg isotope inventory of the early Solar System. Presolar silicate grains were identified in situ, using the NanoSIMS, in the matrix of the ungrouped carbonaceous chondrite Acfer 094. O isotope compositions suggest that the presolar grains of the present study formed in the stellar winds of low mass (M ? ?2.2 × Msolar) red giant or asymptotic giant branch stars of close-to-solar metallicity and thus belong to the most abundant presolar silicate grain group. In order to minimise matrix contributions during spatially poorly resolved Mg isotope analyses (spatial resolution comparable to average grain size), meteorite matrix in the presolar grains’ vicinity was removed using a focussed Ga ion beam. To monitor accuracy, we prepared and analysed O-isotopically regular (Solar System) matrix grains the same way as the presolar grains. The 25Mg/24Mg ratios of all seven successfully analysed presolar silicate grains are identical to that of the Solar System at the precision of our measurements. The 26Mg/24Mg ratios of five grains are also solar but two grains have significant positive anomalies in 26Mg/24Mg. On average, however, 25Mg/24Mg and 26Mg/24Mg ratios are higher than solar by a few %. All grain compositions are consistent with Galactic chemical evolution and, possibly, isotope fractionation caused by interstellar or Solar System processing (sputtering and/or recondensation). The grain with the strongest enrichment in 26Mg relative to 25Mg (?25Mg = 34 ± 25‰, ?26Mg = 127 ± 25‰; where ?xMg = 1000 × [(xMg/24Mg)grain/(xMg/24Mg)meteorite matrix) ? 1] with x = 25 or 26; the reported uncertainty corresponds to 1 ?), probably incorporated 26Al during grain condensation. Our and previously reported Mg isotope data on presolar oxide and silicate grains indicate that the isotopically anomalous O-rich dust component of the Solar System’s parent molecular cloud was heterogeneous with respect to Mg isotope compositions and probably had a higher 26Mg/24Mg ratio on average than that of the present-day Solar System.

János Kodolányi; Peter Hoppe; Elmar Gröner; Christoph Pauly; Frank Mücklich

2014-01-01T23:59:59.000Z

286

Research with fast radioactive isotope beams at RIKEN  

Science Journals Connector (OSTI)

......moments of neutron-rich boron isotopes were measured by the...many neutron-rich isotopes. To exploit fully the...most straightforward determination of the charge distribution...called KISS (KEK isotope separation system......

Tohru Motobayashi; Hiroyoshi Sakurai

2012-01-01T23:59:59.000Z

287

Isotope-Selective Detection and Imaging of Organic Nanolayers  

Science Journals Connector (OSTI)

Isotope-Selective Detection and Imaging of Organic Nanolayers ... We show isotopic selectivity of MRFM for three nuclei, 1H, 31P, and 13C, in organic materials. ... data to further distinguish and characterize the 2 isotopes. ...

H. J. Mamin; T. H. Oosterkamp; M. Poggio; C. L. Degen; C. T. Rettner; D. Rugar

2009-07-09T23:59:59.000Z

288

Isotopes Tell Origin and Operation of the Sun  

E-Print Network [OSTI]

The Iron Sun formed on the collapsed core of a supernova and now acts as a magnetic plasma diffuser, as did the precursor star, separating ions by mass. This process covers the solar surface with lightweight elements and with lighter isotopes of each element. Running difference images expose rigid, iron-rich structures below the fluid photosphere made of lightweight elements. The energy source for the Sun and ordinary stars seems to be neutron-emission and neutron-decay, with partial fusion of the decay product, rather than simple fusion of hydrogen into helium or heavier elements. Neutron-emission from the solar core and neutron-decay generate about sixty five percent of solar luminosity and H-fusion generates about thirty-five percent. The upward flow of H ions maintains mass-separation in the Sun. Only about one percent of this neutron decay product survives its upward journey to depart as solar-wind hydrogen.

O. Manuel; Sumeet A. Kamat; Michael Mozina

2005-09-28T23:59:59.000Z

289

Solvent Isotope-Induced Equilibrium Perturbation for Isocitrate Lyase  

Science Journals Connector (OSTI)

Solvent Isotope-Induced Equilibrium Perturbation for Isocitrate Lyase ... Solvent isotopic composition can influence both the rates of enzyme-catalyzed reactions (solvent kinetic isotope effects) and, in the case of solvent-derived deuterium incorporation into nonexchangeable C–H bonds in products, solvent equilibrium isotope effects. ... In this study, we report the solvent isotope-induced transient change in the concentration and isotopic composition of the reactants. ...

Christine E. Quartararo; Timin Hadi; Sean M. Cahill; John S. Blanchard

2013-11-21T23:59:59.000Z

290

F Band in Isotopically Enriched LiF  

Science Journals Connector (OSTI)

The effect of isotopic composition on the optical obsorption spectrum of the F center in LiF has been investigated. The results of measurements on single crystals of x-ray irradiated Li6F (almost 96% lithium-6) and Li7F (almost 100% lithium-7) indicate that the average F-band width at half-maximum in the former is larger by about 3% at liquid-helium temperature, and by about 1% at room temperature. Theory shows that the half-widths in the two isotopic forms vary inversely as the fourth root of the mass of the alkali ions at low temperature, and as the temperature is increased the predicted half-width difference monotonically decreases to zero. The predicted half-width difference at low temperatures is about 4%, and at room temperature about 1%, both in reasonable agreement with experiment. At both room and liquid-helium temperatures the position of the F-band maximum in Li7F is slightly displaced to higher energy than in Li6F. The peak-position shift is in approximate agreement with the contributions arising from the difference in alkali mass and lattice constant of the two crystals as estimated at low temperature.

Herbert Rabin and Michael Reich

1964-07-06T23:59:59.000Z

291

Electroplating method for producing ultralow-mass fissionable deposits  

DOE Patents [OSTI]

A method for producing ultralow-mass fissionable deposits for nuclear reactor dosimetry is described, including the steps of holding a radioactive parent until the radioactive parent reaches secular equilibrium with a daughter isotope, chemically separating the daughter from the parent, electroplating the daughter on a suitable substrate, and holding the electroplated daughter until the daughter decays to the fissionable deposit.

Ruddy, Francis H. (Monroeville, PA)

1989-01-01T23:59:59.000Z

292

Introduction The Sun is a mass of incandescent gas  

E-Print Network [OSTI]

Chapter 1 Introduction The Sun is a mass of incandescent gas A gigantic nuclear furnace Building that our bodies contain atoms that, like most elements and their isotopes in the Solar System, were part of the molecular cloud from which the Solar System condensed, and were trapped in primitive

Nittler, Larry R.

293

Elements of number theory  

E-Print Network [OSTI]

The dissertation argues for the necessity of a morphosemantic theory of number, that is, a theory of number serviceable both to semantics and morphology. The basis for this position, and the empirical core of the dissertation, ...

Harbour, Daniel, 1975-

2003-01-01T23:59:59.000Z

294

CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...  

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

Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of Appendix C to DOE G...

295

CRAD, Maintenance - Oak Ridge National Laboratory High Flux Isotope...  

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

Maintenance - Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Maintenance - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of...

296

CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...  

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

Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR...

297

CRAD, Maintenance - Oak Ridge National Laboratory High Flux Isotope...  

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

Maintenance - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR CRAD, Maintenance - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR...

298

CRAD, Management- Oak Ridge National Laboratory High Flux Isotope...  

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

Management- Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Management- Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of Appendix C...

299

Enriched Stable Isotope Materials and Chemistry | ornl.gov  

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

Enriched Stable Isotope Materials and Chemistry SHARE Enriched Stable Isotope Materials and Chemistry Reductiondistillation of calcium-48 metal valued at over 900,000. An...

300

Isotopic Analysis- Gas At Chena Geothermal Area (Kolker, Et Al...  

Open Energy Info (EERE)

Laboratory sampling and analysis of He isotopes from Chena Hot Springs. Notes Helium isotope measurements indicate there is no magmatic or mantle input at the Chena Geothermal...

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Development of a Micropyrolyzer for Enhanced Isotope Ratio Measurement...  

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

Micropyrolyzer for Enhanced Isotope Ratio Measurement. Development of a Micropyrolyzer for Enhanced Isotope Ratio Measurement. Abstract: This paper presents design, fabrication and...

302

Standards for publication of isotope ratio and chemical data in Chemical Geology  

E-Print Network [OSTI]

Editorial Standards for publication of isotope ratio and chemical data in Chemical Geology Abstract reporting data for internation- al standards that were analyzed in the same laboratory, using the same and trace elements, there are a large number of reasonably well-characterized whole rock standards from

Rudnick, Roberta L.

303

Laser trapping of short-lived radioactive isotopes  

Science Journals Connector (OSTI)

We describe an experiment which demonstrates the feasibility of trapping significant quantities of short-lived radioactive atoms with laser light. A thermal beam of 22.5 sec half-life Na21 atoms was produced on-line at the LBL 88’’ Cyclotron. After decelerating the beam using a Zeeman-tuned slowing technique we stored about 4×103 Na21 atoms in a magneto-optical trap. The number of trapped atoms is large enough to be used in experimental studies of the beta decay of Na21. The basic method can be adapted for other rare isotopes.

Z-T. Lu; C. Bowers; S. J. Freedman; B. K. Fujikawa; J. L. Mortara; S-Q. Shang; K. P. Coulter; L. Young

1994-06-13T23:59:59.000Z

304

Isotopes  

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

are saving lives, advancing cutting-edge research and keeping the U.S. safe. Strontium-82 produced at Los Alamos is used in hospitals nation- and world-wide for critical...

305

ISOTOPES  

E-Print Network [OSTI]

Research, Division of Nuclear Sciences of the Basic Energy Sciences ProgramResearch, Division of Nuclear Sciences of the Basic Energy Sciences Program

Lederer, C. Michael

2013-01-01T23:59:59.000Z

306

ISOTOPES  

E-Print Network [OSTI]

5-7. 1975, British Nuclear Engineering Society (1975). 87.London, March British Nuclear Engineering Society (1975).T.H. Pigford, Nuclear Chemical Engineering (1St edition),

Lederer, C. Michael

2013-01-01T23:59:59.000Z

307

ISOTOPES  

E-Print Network [OSTI]

uranium, heavy-water-moderated CANDU reactor, as contrastedis important, and in the CANDU power reactor, which uses

Lederer, C. Michael

2013-01-01T23:59:59.000Z

308

Isotopic Analysis At Geysers Area (Lambert & Epstein, 1992) | Open Energy  

Open Energy Info (EERE)

Isotopic Analysis- Rock At Geysers Area (Lambert & Isotopic Analysis- Rock At Geysers Area (Lambert & Epstein, 1992) Exploration Activity Details Location Geysers Area Exploration Technique Isotopic Analysis- Rock Activity Date Usefulness useful DOE-funding Unknown Notes Measurements of 180/160, 13C/12C and D/H ratio variations were made by the usual methods (McCrea, 1950; Taylor and Epstein, 1962; Epstein and Taylor, 1970) using mass spectrometers of the type described by Nier (1947) with modifications by McKinney et al. (1950). Results are reported in 8-notation with respect to the SMOW (Craig, 1961 ) and PDB (Urey et al., 1951 ) standards. Analytical precisions for multiple analyses of any single sample were _+ 0.2%0 for oxygen and carbon and _ 1%o for hydrogen. Inhomogeneities of cuttings fractions gave rise to variations within single cuttings

309

Seasonal variations in the stable carbon isotopic signature of biogenic methane in a coastal sediment  

SciTech Connect (OSTI)

Systematic seasonal variations in the stable carbon isotopic signature of methane gas occur in the anoxic sediments of Cape Lookout Bight, a lagoonal basin on North Carolina's Outer Banks. Values for the carbon isotope ratio (delta /sup 13/C) of methane range from -57.3 per mil during summer to -68.5 per mil during winter in gas bubbles with an average methane content of 95%. The variations are hypothesized to result from changes in the pathways of microbial methane production and cycling of key substrates including acetate and hydrogen. The use of stable isotopic signatures to investigate the global methane cycle through mass balance calculations, involving various sediment and soil biogenic sources, appears to require seasonally averaged data from individual sites. 17 references, 2 figures, 2 tables.

Martens, C.S.; Blair, N.E.; Green, C.D.; Des Marais, D.J.

1986-09-19T23:59:59.000Z

310

Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope  

Open Energy Info (EERE)

Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Flow Of Mantle Fluids Through The Ductile Lower Crust- Helium Isotope Trends Details Activities (5) Areas (5) Regions (0) Abstract: Heat and mass are injected into the shallow crust when mantle fluids are able to flow through the ductile lower crust. Minimum He-3/He-4 ratios in surface fluids from the northern Basin and Range Province, western North America, increase systematically from low crustal values in the east to high mantle values in the west, a regional trend that correlates with the rates of active crustal deformation. The highest ratios occur where the extension and shear strain rates are greatest. The

311

Device and method for separating oxygen isotopes  

DOE Patents [OSTI]

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.

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

1984-01-01T23:59:59.000Z

312

Selected Isotopes for Optimized Fuel Assembly Tags  

SciTech Connect (OSTI)

In support of our ongoing signatures project we present information on 3 isotopes selected for possible application in optimized tags that could be applied to fuel assemblies to provide an objective measure of burnup. 1. Important factors for an optimized tag are compatibility with the reactor environment (corrosion resistance), low radioactive activation, at least 2 stable isotopes, moderate neutron absorption cross-section, which gives significant changes in isotope ratios over typical fuel assembly irradiation levels, and ease of measurement in the SIMS machine 2. From the candidate isotopes presented in the 3rd FY 08 Quarterly Report, the most promising appear to be Titanium, Hafnium, and Platinum. The other candidate isotopes (Iron, Tungsten, exhibited inadequate corrosion resistance and/or had neutron capture cross-sections either too high or too low for the burnup range of interest.

Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J.; Hurley, David E.

2008-10-01T23:59:59.000Z

313

Atomic vapor laser isotope separation of lead-210 isotope  

DOE Patents [OSTI]

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.

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

1999-01-01T23:59:59.000Z

314

Atomic vapor laser isotope separation of lead-210 isotope  

DOE Patents [OSTI]

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.

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

1999-08-31T23:59:59.000Z

315

Mass of Si-24  

E-Print Network [OSTI]

PHYSICAL REVIEW C VOLUME 22, NUMBER 1 JULY 1980 Mass of Si R. E. Tribble, D. M. Tanner, and A. F. Zeller* Cyclotron Institute and Physics Department, Texas A&M University, College Station, Texas 77843 (Received 11 January 1980) The Si( He, 'He... quintet. The theoretical predictions are from Ref. 14. Nuclides +Si- 4AI Al Mg +Mg 24Na +Na- 4Ne Experimental 4&, 5661(24) 5179(9) 4735(2) 42840. 0) Predicted &&, 5646 5184 4722 4260 15 -5 12 24 +37 +12 -12 -37 ay g@eXQ ~~ thearC C...

Tribble, Robert E.; Tanner, D. M.; Zeller, A. F.

1980-01-01T23:59:59.000Z

316

RAPID FUSION METHOD FOR DETERMINATION OF PLUTONIUM ISOTOPES IN LARGE RICE SAMPLES  

SciTech Connect (OSTI)

A new rapid fusion method for the determination of plutonium in large rice samples has been developed at the Savannah River National Laboratory (Aiken, SC, USA) that can be used to determine very low levels of plutonium isotopes in rice. The recent accident at Fukushima Nuclear Power Plant in March, 2011 reinforces the need to have rapid, reliable radiochemical analyses for radionuclides in environmental and food samples. Public concern regarding foods, particularly foods such as rice in Japan, highlights the need for analytical techniques that will allow very large sample aliquots of rice to be used for analysis so that very low levels of plutonium isotopes may be detected. The new method to determine plutonium isotopes in large rice samples utilizes a furnace ashing step, a rapid sodium hydroxide fusion method, a lanthanum fluoride matrix removal step, and a column separation process with TEVA Resin? cartridges. The method can be applied to rice sample aliquots as large as 5 kg. Plutonium isotopes can be determined using alpha spectrometry or inductively-coupled plasma mass spectrometry (ICP-MS). The method showed high chemical recoveries and effective removal of interferences. The rapid fusion technique is a rugged sample digestion method that ensures that any refractory plutonium particles are effectively digested. The MDA for a 5 kg rice sample using alpha spectrometry is 7E-5 mBq g{sup -1}. The method can easily be adapted for use by ICP-MS to allow detection of plutonium isotopic ratios.

Maxwell, S.

2013-03-01T23:59:59.000Z

317

Prediction of equilibrium Li isotope fractionation between minerals and aqueous solutions at high P and T: an efficient ab initio approach  

E-Print Network [OSTI]

The mass-dependent equilibrium stable isotope fractionation between different materials is an important geochemical process. Here we present an efficient method to compute the isotope fractionation between complex minerals and fluids at high pressure, P, and temperature, T, representative for the Earth's crust and mantle. The method is tested by computation of the equilibrium fractionation of lithium isotopes between aqueous fluids and various Li bearing minerals such as staurolite, spodumene and mica. We are able to correctly predict the direction of the isotope fractionation as observed in the experiments. On the quantitative level the computed fractionation factors agree within 1.0 permil with the experimental values indicating predictive power of ab initio methods. We show that with ab initio methods we are able to investigate the underlying mechanisms driving the equilibrium isotope fractionation process, such as coordination of the fractionating elements, their bond strengths to the neighboring atoms, c...

Kowalski, Piotr M

2011-01-01T23:59:59.000Z

318

Stable isotope patterns found in early Eocene equid tooth rows of North America: Implications for reproductive behavior and paleoclimate  

Science Journals Connector (OSTI)

Abstract Reproductive behaviors of early Eocene equids were likely different from their modern-day counterparts as a result of their small body size and warmer global temperatures. To better understand the paleoenvironment and ecology of these early horses, teeth of Protorohippus montanum jaws from a single stratigraphic locality in early Eocene sedimentary deposits of Wyoming were sampled for oxygen and carbon isotope analysis. These enamel data along with an inferred body mass of ~ 7.5 kg suggests that adult teeth formed over a matter of months, with the final tooth erupting at ~ 1.3 years of age. Thus, average isotopic values from each tooth likely represent environmental conditions from a single season. Results indicate two isotopic patterns. In the case of isotopic “pattern A,” the second forming molars (m/2s) have significantly lower isotopic ratios compared to other teeth within the jaw. This suggests the first forming molars (m/1s) formed during a cooling fall season, followed by formation of the m/2s during the cooler winter. In the case of isotopic “pattern B,” results suggest that m/1s formed during a warming spring season, while the m/2s formed during the following warmer summer season. Isotopic ratios of m/1s may represent an individual's birth season (or in utero season, depending on timing of initial formation), implying that early equids experienced at least two birth seasons per year. These results suggest that temperatures and reduced seasonality of the early Eocene played a strong role in early equid birth cycles. Lastly, the mean and variance in carbon and oxygen isotope ratios was not significantly different across tooth positions of all jaws when all individuals were grouped together, regardless of their pattern assignment. Such results indicate that isotopic data from fourth premolars, first molars, second molars, and third molars can be combined for purposes of temporal reconstructions of paleoclimate, thus increasing the potential sample sizes for these types of studies.

Abigail R. D’Ambrosia; William C. Clyde; Henry C. Fricke; Amy E. Chew

2014-01-01T23:59:59.000Z

319

Isotopic composition of Silurian seawater  

SciTech Connect (OSTI)

Direct isotopic analyses of 21 samples of the Silurian hydrosphere preserved as fluid inclusions in Silurian halite deposits in the Michigan Basin Salina Group yield delta/sup 18/O, deltaD ranging from 0.2 to +5.9 and -26 to -73, respectively. delta/sup 18/O has the same range as observed for modern halite facies evaporite waters and is a few per thousand higher than 100 analyses of fluid inclusions in Permian halite. deltaD is about 20 to 30 per thousand lower than modern and Permian examples. The trajectory of evaporating seawater on a deltaD-delta/sup 18/O diagram initially has a positive slope of 3-6, but hooks strongly downward to negative values, the shape of the hook depending upon humidity. Halite begins to precipitate at delta values similar to those observed for the most /sup 18/O rich fluid inclusions. Subsequent evaporation yields progressively more negative delta values as observed for the fluid inclusions. The fluid inclusion data can be readily explained in terms of evaporating seawater and are consistent with the degree of evaporation deduced from measured bromide profiles. These data are strongly inconsistent with arguments that Silurian seawater was 5.5 per thousand depleted in /sup 18/O. delta/sup 18/O for evaporite waters is systematically related to that of seawater, and does not show a -5.5 per thousand shift in the Silurian, even allowing for variables which affect the isotope evaporation trajectory. The lower deltaD may indicate a component of gypsum dehydration waters or may suggest a D-depleted Silurian hydrosphere.

Knauth, L.P.; Kealy, S.; Larimer, S.

1985-01-01T23:59:59.000Z

320

High-Performance Mass Spectrometry Facility  

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

HPMSF Overview HPMSF Overview Section 2-4-1 High-Performance Mass Spectrometry Facility The High-Performance Mass Spectrometry Facility (HPMSF) provides state-of-the-art mass spectrometry (MS) and separations instrumentation that has been refined for leading-edge analysis of biological problems with a primary emphasis on proteomics. Challenging research in proteomics, cell signaling, cellular molecular machines, and high-molecular weight systems receive the highest priority for access to the facility. Current research activities in the HPMSF include proteomic analyses of whole cell lysates, analyses of organic macro-molecules and protein complexes, quantification using isotopically labeled growth media, targeted proteomics analyses of subcellular fractions, and nucleic acid analysis of

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

THE MASS DISTRIBUTION OF SUBGIANT PLANET HOSTS  

SciTech Connect (OSTI)

High mass stars are hostile to Doppler measurements due to rotation and activity on the main-sequence, so RV searches for planets around massive stars have relied on evolved stars. A large number of planets have been found around evolved stars with M > 1.5 M{sub Sun }. To test the robustness of mass determinations, Lloyd compared mass distributions of planet hosting subgiants with distributions from integrating isochrones and concluded that it is unlikely the subgiant planet hosts are this massive, but rather that the mass inferences are systematically in error. The conclusions of Lloyd have been called in to question by Johnson et al., who show TRILEGAL-based mass distributions that disagree with the mass distributions in Lloyd, which they attribute to Malmquist bias. Johnson et al. argue that the very small spectroscopic observational uncertainties favor high masses, and there are a large number of high mass sub giants in RV surveys. However, in this Letter, it is shown that Malmquist bias does not impact the mass distributions, but the mass distribution is sensitive to Galaxy model. The relationship needed to reconcile the subgiant planet host masses with any model of the Galactic stellar population is implausible, and the conclusion of Lloyd that spectroscopic mass determinations of subgiants are likely to have been overestimated is robust.

Lloyd, James P. [Department of Astronomy, Cornell University, Ithaca, NY (United States)

2013-09-01T23:59:59.000Z

322

Transition of Iodine Analysis to Accelerator Mass Spectrometry  

SciTech Connect (OSTI)

This NA 22 funded research project investigated the transition of iodine isotopic analyses from thermal ionization mass spectrometry (TIMS) to an accelerator mass spectrometry (AMS) system. Previous work (Fiscal Year 2010) had demonstrated comparable data from TIMS and AMS. With AMS providing comparable data with improved background levels and vastly superior sample throughput, improvement in the sample extraction from environmental sample matrices was needed to bring sample preparation throughput closer to the operation level of the instrument. Previous research used an extraction chemistry that was not optimized for yield or refined for reduced labor to prove the principle. This research was done to find an extraction with better yield using less labor per sample to produce a sample ready for the AMS instrument. An extraction method using tetramethyl ammonium hydroxide (TMAH) was developed for removal of iodine species from high volume air filters. The TMAH with gentle heating was superior to the following three extraction methods: ammonium hydroxide aided by sonication, acidic and basic extraction aided by microwave, and ethanol mixed with sodium hydroxide. Taking the iodine from the extraction solvent to being ready for AMS analysis was accomplished by a direct precipitation, as well as, using silver wool to harvest the iodine from the TMAH. Portions of the same filters processed in FY 2010 were processed again with the improved extraction scheme followed by successful analysis by AMS at the Swiss Federal Institute of Technology. The data favorably matched the data obtained in 2010. The time required for analysis has been reduced over the aqueous extraction/AMS approach developed in FY 2010. For a hypothetical batch of 30 samples, the AMS methodology is about 10 times faster than the traditional gas phase chemistry and TIMS analysis. As an additional benefit, background levels for the AMS method are about 1000 times lower than TIMS. This results from the fundamental mechanisms of ionization in the AMS system and which produces a beneficial cleanup of molecular interferences. Continued clean operation of the extraction process was demonstrated through blank analysis included with all sample sets analyzed. INL work showed improvement on the first year’s demonstration of AMS vs. TIMS. An improved extraction of high volume air filters followed by isotopic analysis by AMS, can be used successfully to make iodine measurements with results comparable to those obtained by filter combustion and TIMS analysis. More progress on the conversion from an extract solution to an AMS sample ready for analysis is still needed. Although the preparation scheme through AMS is already at a higher performing thoughput than TIMS, the chemical preparation cannot match the instrument capability for number of samples per day without further development.

M. L. Adamic; J. E. Olson; D. D. Jenson; J. G. Eisenmenger; M. G. Watrous

2012-09-01T23:59:59.000Z

323

Boron isotopes in tourmaline as a tracer of metasomatic processes in the Bamble sector of Southern Norway  

Science Journals Connector (OSTI)

For the B isotope determinations in tourmaline by secondary ion mass spectrometry...2009a) was used. The O? primary ion beam was accelerated to 14.5 keV at a beam current of 1 nA. The diameter of the spot used fo...

R. Bast; E. E. Scherer; K. Mezger…

2014-10-01T23:59:59.000Z

324

Influence of longitudinal isotope substitution on the thermal conductivity of carbon nanotubes: Results of nonequilibrium molecular dynamics and local density functional calculations  

SciTech Connect (OSTI)

We report reverse nonequilibrium molecular dynamics calculations of the thermal conductivity of isotope substituted (10,10) carbon nanotubes (CNTs) at 300 K. {sup 12}C and {sup 14}C isotopes both at 50% content were arranged either randomly, in bands running parallel to the main axis of the CNTs or in bands perpendicular to this axis. It is found that the systems with randomly distributed isotopes yield significantly reduced thermal conductivity. In contrast, the systems where the isotopes are organized in patterns parallel to the CNTs axis feature no reduction in thermal conductivity when compared with the pure {sup 14}C system. Moreover, a reduction of approximately 30% is observed in the system with the bands of isotopes running perpendicular to the CNT axis. The computation of phonon dispersion curves in the local density approximation and classical densities of vibrational states reveal that the phonon structure of carbon nanotubes is conserved in the isotope substituted systems with the ordered patterns, yielding high thermal conductivities in spite of the mass heterogeneity. In order to complement our conclusions on the {sup 12}C-{sup 14}C mixtures, we computed the thermal conductivity of systems where the {sup 14}C isotope was turned into pseudo-atoms of 20 and 40 atomic mass units.

Leroy, Frédéric, E-mail: f.leroy@theo.chemie.tu-darmstadt.de; Böhm, Michael C., E-mail: boehm@theo.chemie.tu-darmstadt.de [Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, D-64287 Darmstadt (Germany); Schulte, Joachim [Bruker Biospin GmbH, Silberstreifen, D-76287 Rheinstetten (Germany)] [Bruker Biospin GmbH, Silberstreifen, D-76287 Rheinstetten (Germany); Balasubramanian, Ganesh [Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States)] [Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States)

2014-04-14T23:59:59.000Z

325

Measurement of the (3s3p){sup 1}P-(3s3d){sup 1}D isotope shift in Mg i  

SciTech Connect (OSTI)

We present measurements of the isotope shift for the (3s3p){sup 1}P-(3s3d){sup 1}D transitions at 881 nm in Mg i. The three stable magnesium isotopes yielded a shift {sup 24}Mg-{sup 25}Mg of (1342{+-}20) MHz and {sup 25}Mg-{sup 26}Mg of (1175{+-}23) MHz. Measured shifts are consistent with recent relativistic many-body calculations of the mass effect.

Steenstrup, M. P.; Brusch, A.; Jensen, B. B.; Thomsen, J. W. [Niels Bohr Institute, Universitetsparken 5, DK-2100 Copenhagen (Denmark); Hald, J. [Danish Fundamental Metrology, Matematiktorvet 307, DK-2008 Kgs. Lyngby (Denmark)

2010-11-15T23:59:59.000Z

326

Extraction and Determination of Boron Isotopic Composition in Tourmalines  

Science Journals Connector (OSTI)

Tourmaline is an abundant boron-rich alumosilicate mineral with complex chemistry and rich in Fe, Mg, Al, Si elements. In this study, tourmaline samples were decomposed by alkali fusion method, and then the boron was separated and purified using three different procedures. It was found that both Fe3+ and Al3+ ions, rich in tourmaline samples seriously, which affected the accurate determination of boron concentration by Azomethine-H spectrophotometric method and also caused a loss of boron by specific adsorption when large amount of amorphous hydroxide precipitate formed in ion-exchange columns. The addition of small amount of EDTA can eliminate the influence, but brings serious isobaric interference on boron isotopic analysis by TIMS. Finally, a three-column ion-exchange procedure was established including the first mixed resin column, the peristaltic pump coupled boron specific resin column, and the second mixed resin column, which ensures the full recovery of boron (> 99%) from tourmaline samples with complex matrices. The PTIMS-Cs2BO2+-static double-collection method was established by selecting H3-H4 Faraday cups and optimizing parameters in Zoom Optics (Focus Quad: 15; Dispersion Quad: ?85) in a Triton TI mass spectrometer. The determined average 11B/10B value of NIST SRM 951 standard boron solution was 4.05044±0.00012 (2?, n = 8, 1 ?g B), which was superior to the dynamic collection method in internal/external precision. A ?11B value of ?0.3% for NIST SRM 951 through the same pretreatment procedure was obtained, indicating that there was no isotopic fractionation occurred during the extraction procedure. The comparison of boron isotopic compositions in natural samples by TIMS and MC-ICP-MS after the chemistry procedure indicated that ?11B values determined by the static PTIMS-Cs2BO2+ method were in good agreement with that by MC-ICP-MS.

Xiong YAN; Shao-Yong JIANG; Hai-Zhen WEI; Yan YAN; He-Pin WU; Wei PU

2012-01-01T23:59:59.000Z

327

Laser Ablation Molecular Isotopic Spectrometry: Parameter influence on boron isotope measurements  

Science Journals Connector (OSTI)

Laser Ablation Molecular Isotopic Spectrometry (LAMIS) was recently reported for optical isotopic analysis of condensed samples in ambient air and at ambient pressure. LAMIS utilizes molecular emissions which exhibit larger isotopic spectral shits than in atomic transitions. For boron monoxide 10BO and 11BO, the isotopic shifts extend from 114 cm?1 (0.74 nm) to 145–238 cm?1 (5–8 nm) at the B 2?+ (v = 0) ? X 2?+ (v = 2) and A 2?i (v = 0) ? X 2?+ (v = 3) transitions, respectively. These molecular isotopic shifts are over two orders of magnitude larger than the maximum isotopic shift of approximately 0.6 cm?1 in atomic boron. This paper describes how boron isotope abundance can be quantitatively determined using LAMIS and how atomic, ionic, and molecular optical emission develops in a plasma emanating from laser ablation of solid samples with various boron isotopic composition. We demonstrate that requirements for spectral resolution of the measurement system can be significantly relaxed when the isotopic abundance ratio is determined using chemometric analysis of spectra. Sensitivity can be improved by using a second slightly delayed laser pulse arriving into an expanding plume created by the first ablation pulse.

Xianglei Mao; Alexander A. Bol'shakov; Dale L. Perry; Osman Sorkhabi; Richard E. Russo

2011-01-01T23:59:59.000Z

328

Mass-spectrometric determination of americium and curium in spent nuclear fuel  

SciTech Connect (OSTI)

It was shown that it is possible to carry out isotopic analysis of americium and curium isolated in one fraction from a sample of nuclear fuel without chemical separation of the elements. This became possible as a result of the use in the mass-spectrometric measurements of a highly efficient ion source with surface ionization in a partially closed cavity. With this ion source, the content of americium and curium in nuclear fuel was determined by isotope dilution.

Kalygin, V.V.; Gabeskiriya, V.Ya.

1987-01-01T23:59:59.000Z

329

Number Counts and Dynamical Vacuum Cosmologies  

E-Print Network [OSTI]

We study non-linear structure formation in an interacting model of the dark sector of the Universe in which the dark energy density decays linearly with the Hubble parameter, $\\rho_{\\Lambda} \\propto H$, leading to a constant-rate creation of cold dark matter. We derive all relevant expressions to calculate the mass function and the cluster number density using the Sheth-Torman formalism and show that the effect of the interaction process is to increase the number of bound structures of large masses ($M \\gtrsim 10^{14} M_{\\odot}h^{-1}$) when compared to the standard $\\Lambda$CDM model. Since these models are not reducible to each other, this number counts signature can in principle be tested in future surveys.

N. Chandrachani Devi; H. A. Borges; S. Carneiro; J. S. Alcaniz

2014-07-07T23:59:59.000Z

330

Number Counts and Dynamical Vacuum Cosmologies  

E-Print Network [OSTI]

We study non-linear structure formation in an interacting model of the dark sector of the Universe in which the dark energy density decays linearly with the Hubble parameter, $\\rho_{\\Lambda} \\propto H$, leading to a constant-rate creation of cold dark matter. We derive all relevant expressions to calculate the mass function and the cluster number density using the Sheth-Torman formalism and show that the effect of the interaction process is to increase the number of bound structures of large masses ($M \\gtrsim 10^{14} M_{\\odot}h^{-1}$) when compared to the standard $\\Lambda$CDM model. Since these models are not reducible to each other, this number counts signature can in principle be tested in future surveys.

Devi, N Chandrachani; Carneiro, S; Alcaniz, J S

2014-01-01T23:59:59.000Z

331

Isotope ratio determination in boron analysis  

Science Journals Connector (OSTI)

Traditionally, boron (B) isotope ratios have been determined using thermal ionization...+, Cs+, or O-...for analyte ionization. TIMS can be used in negative or positive ion modes with high sensitivity and precisi...

Ram N. Sah; Patrick H. Brown

1998-12-01T23:59:59.000Z

332

ICE CORE RECORDS | Greenland Stable Isotopes  

Science Journals Connector (OSTI)

Abstract Greenland ice cores contain a wealth of information on past climatic conditions throughout the Northern Hemisphere. A historical perspective on the climatic interpretation of stable isotopes in water and ice is presented in the introduction, while the remainder of the article is devoted to the current interpretation of stable isotope data from Greenland ice cores. The progress in our understanding of stable isotope signals, on timescales from seasons to glacial cycles, is discussed and evaluated through numerous examples from Greenland ice cores. Stable isotope profiles from the Camp Century, Dye-3, GISP2, GRIP, NGRIP, and Renland deep ice cores are emphasized, as they all provide climatic information dating back into the Eemian period.

B.M. Vinther; S.J. Johnsen

2013-01-01T23:59:59.000Z

333

Nuclear Astrophysics in Rare Isotope Facilities  

E-Print Network [OSTI]

Nuclear reactions in stars are difficult to measure directly in the laboratory at the small astrophysical energies. In recent years indirect methods with rare isotopes have been developed and applied to extract low-energy astrophysical cross sections.

C. A. Bertulani

2009-11-02T23:59:59.000Z

334

Gaseous isotope separation using solar wind phenomena  

Science Journals Connector (OSTI)

...isotope separation using solar wind phenomena Chia-Gee...essentially the same as that of the solar wind propagation, in which...the author was measuring solar wind parameters under Dr. H. S. Bridge at Massachusetts Institute of Technology in...

Chia-Gee Wang

1980-01-01T23:59:59.000Z

335

NONRADIOGENIC ISOTOPES IN GEOLOGY: A REVIEW  

Science Journals Connector (OSTI)

...has revised Brown's figures. Seaborg and Pearlman (1948) and more recently...51, p. 263-300. and Jenks, Glenn (1944) Isotopic composition of...Science,vol. 79, p. 565. Seaborg, Glenn T., and Pearlman, I. (1948...

336

Storage of Hydrogen Isotopes in Uranium Alloys  

Science Journals Connector (OSTI)

Tritium Properties and Interactions with Material / Proceedings of the Third Topical Meeting on Tritium Technology in Fission, Fusion and Isotopic Applications (Toronto, Ontario, Canada, May 1-6, 1988)

T. Yamamoto; Supardjo; T. Terai; F. Ono; S. Tanaka; M. Yamawaki

337

Mechanistic studies using kinetic isotope effects  

E-Print Network [OSTI]

MECHANISTIC STUDIES USING KINETIC ISOTOPE EFFECTS A Thesis by BRIAN E. SCHULMFIER Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requtrements for the degree of MASTER OF SCIENCE December... 1999 Major Subject: Chemistry MECHANISTIC STUDIES USING KINETIC ISOTOPE EFFECTS A Thesis by BRIAN E. SCHULMEIER Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved...

Schulmeier, Brian E.

2012-06-07T23:59:59.000Z

338

Isotope/element fractionation during surface adsorption  

Science Journals Connector (OSTI)

The adsorption of ions onto mineral surfaces accompanies isotope/element fractionation in planets and asteroids. A model based on simple classical physics is presented to predict these fractionations. The agreement between the experimentally observed isotope/element ratios and their predicted values is found to be excellent. This fractionation can be demonstrated experimentally in advanced physics laboratories using macroscopic particles. The success of the model shows students that even a very complex naturally occurring process can be explained quantitatively with simple physics.

Gamini Seneviratne; Asiri Nanayakkara

2004-01-01T23:59:59.000Z

339

The Oxygen core inside the Magnesium isotopes  

E-Print Network [OSTI]

We have studied the ground state bulk properties of magnesium isotopes using axially symmetric relativistic mean field formalism. The BCS pairing approach is employed to take care of the pairing correlation for the open shell nuclei. The contour plot of the nucleons distribution are analyzed at various parts of the nucleus, where clusters are located. The presence of an $^{16}$O core along bubble like $\\alpha$-particle(s) and few {\\it nucleons} are found in the Mg isotopes.

Bhuyan, M

2013-01-01T23:59:59.000Z

340

Laser Spectroscopy of Short Lived Rare Earth Isotopes  

Science Journals Connector (OSTI)

The ISAC facility at TRIUMF is able to produce intense beams of mass?separated radioactive isotopes of the alkali and the rare earth elements with unprecedented intensities. This will allow our laser spectroscopy collaboration to extend the studies of exotic nuclei for these elements further away from the valley of stability into regions so far inaccessible at other facilities thus allowing a more stringent test of the descriptive and predictive power of global nuclear models. Our effort which involves groups and researchers from the U.S. (TAMU) Japan (JAERI) and Canada (TRIUMF McGill and Calgary Universities) is based on collinear laser spectroscopy in a fast beam. In this method atoms or ions are excited by laser light in collinear geometry. In this way measurements of the optical isotope shift yield the nuclear charge radii and measurements of the hyperfine structure the nuclear moments. The excitation can be done by cw?lasers or alternatively by pulsed lasers without a loss in sensitivity if bunched radioactive ion beams are available. In its basic version the resonances of the spectral lines are observed optically at right angles. However the sensitivity will be increased through modifications using particle or nuclear radiation detection. The progress and the plans of our collaboration will be described.

H. A. Schuessler; F. Buchinger; H. Iimura

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

E-Print Network 3.0 - alpha-deuterium isotope effects Sample...  

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

deuterium isotope effects Search Powered by Explorit Topic List Advanced Search Sample search results for: alpha-deuterium isotope effects Page: << < 1 2 3 4 5 > >> 1 ISOTOPE...

342

Strontium and carbon isotope stratigraphy of the Llandovery (Early Silurian): Implications for tectonics and weathering  

E-Print Network [OSTI]

Strontium and carbon isotope stratigraphy of the Llandovery (Early Silurian): Implications online 2 June 2010 Keywords: Silurian Strontium isotopes Carbon isotopes Weathering K-bentonites A high

Saltzman, Matthew R.

343

Isotope Program Facilities | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

include the High Flux Isotope Reactor at Oak Ridge National Laboratory and the Advanced Test Reactor at Idaho National Laboratory. The DOE Isotope Program also supports isotope...

344

Oxygen isotope fractionation in the vacuum ultraviolet photodissociation of carbon monoxide: Wavelength, pressure and temperature dependency.  

E-Print Network [OSTI]

Oxygen isotope fractionation in the vacuum ultravioletmeasurement of the associated oxygen isotopic composition ofwavelength dependency of the oxygen isotopic composition in

Chakraborty, Subrata

2013-01-01T23:59:59.000Z

345

E-Print Network 3.0 - applied isotope techniques Sample Search...  

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

Sciences and Ecology ; Biology and Medicine 100 Electrochemical Isotope Effect and Lithium Isotope Separation Jay R. Black, Summary: that the magnitude of isotopic...

346

Coronal structure of low-mass stars  

Science Journals Connector (OSTI)

......structure of low-mass stars Pauline Lang...loss in the stellar wind and X-ray emission...use reconstructed maps of the radial magnetic...strong as the stellar mass decreases, while...magnitude of the open (wind-bearing) magnetic...either rotational velocity or Rossby number......

Pauline Lang; Moira Jardine; Jean-François Donati; Julien Morin; Aline Vidotto

2012-08-01T23:59:59.000Z

347

UW Cosmogenic Isotopes Al-Be 1 EXTRACTION OF Al & Be FROM QUARTZ FOR ISOTOPIC ANALYSIS  

E-Print Network [OSTI]

UW Cosmogenic Isotopes Al-Be 1 EXTRACTION OF Al & Be FROM QUARTZ FOR ISOTOPIC ANALYSIS Summary This method is used to separate Al and Be for AMS analysis from pure quartz samples. After adding Be carrier, quartz is dissolved in HF. The solution is sub-sampled for determination of total Al content, then dried

Stone, John

348

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

SciTech Connect (OSTI)

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.

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

1989-01-01T23:59:59.000Z

349

Influence of liquid structure on diffusive isotope separation in molten silicates and aqueous solutions  

SciTech Connect (OSTI)

Molecular diffusion in natural volcanic liquids discriminates between isotopes of major ions (e.g., Fe, Mg, Ca, and Li). Although isotope separation by diffusion is expected on theoretical grounds, the dependence on mass is highly variable for different elements and in different media. Silicate liquid diffusion experiments using simple liquid compositions were carried out to further probe the compositional dependence of diffusive isotopic discrimination and its relationship to liquid structure. Two diffusion couples consisting of the mineral constituents anorthite (CaAl{sub 2}Si{sub 2}O{sub 8}; denoted AN), albite (NaAlSi{sub 3}O{sub 8}; denoted AB), and diopside (CaMgSi{sub 2}O{sub 6}; denoted DI) were held at 1450°C for 2 h and then quenched to ambient pressure and temperature. Major-element as well as Ca and Mg isotope profiles were measured on the recovered quenched glasses. In both experiments, Ca diffuses rapidly with respect to Si. In the AB–AN experiment, D{sub Ca}/D{sub Si} ~ 20 and the efficiency of isotope separation for Ca is much greater than in natural liquid experiments where D{sub Ca}/D{sub Si} ~ 1. In the AB–DI experiment, D{sub Ca}/D{sub Si} ~ 6 and the efficiency of isotope separation is between that of the natural liquid experiments and the AB–AN experiment. In the AB–DI experiment, D{sub Mg}/D{sub Si} ~ 1 and the efficiency of isotope separation for Mg is smaller than it is for Ca yet similar to that observed for Mg in natural liquids. The results from the experiments reported here, in combination with results from natural volcanic liquids, show clearly that the efficiency of diffusive separation of Ca isotopes is systematically related to the solvent-normalized diffusivity—the ratio of the diffusivity of the cation (D{sub Ca}) to the diffusivity of silicon (D{sub Si}). The results on Ca isotopes are consistent with available data on Fe, Li, and Mg isotopes in silicate liquids, when considered in terms of the parameter D{sub cation}/D{sub Si}. Cations diffusing in aqueous solutions display a similar relationship between isotopic separation efficiency and D{sub cation} =D{sub H 2 O} , although the efficiencies are smaller than in silicate liquids. Our empirical relationship provides a tool for predicting the magnitude of diffusive isotopic effects in many geologic environments and a basis for a more comprehensive theory of isotope separation in liquid solutions. We present a conceptual model for the relationship between diffusivity and liquid structure that is consistent with available data.

Watkins, J.M.; DePaolo, D.J.; Ryerson, F.J.; Peterson, B.

2011-03-01T23:59:59.000Z

350

Energy or Mass and Interaction  

E-Print Network [OSTI]

A review. Problems: 1-Many empirical parameters and large dimension number; 2-Gravitation and Electrodynamics are challenged by dark matter and energy. Energy and nonlinear electrodynamics are fundamental in a unified nonlinear interaction. Nuclear energy appears as nonlinear SU(2) magnetic energy. Gravitation and electromagnetism are unified giving Einstein's equation and a geometric energy momentum tensor. A solution energy in the newtonian limit gives the gravitational constant G. Outside of this limit G is variable. May be interpreted as dark matter or energy. In vacuum, known gravitational solutions are obtained. Electromagnetism is an SU(2) subgroup. A U(1) limit gives Maxwell's equations. Geometric fields determine a generalized Dirac equation and are the germ of quantum physics. Planck's h and of Einstein's c are given by the potential and the metric. Excitations have quanta of charge, flux and spin determining the FQHE. There are only three stable 1/2 spin fermions. Mass is a form of energy. The rest energies of the fermions give the proton/electron mass ratio. Potential excitations have energies equal to the weak boson masses allowing a geometric interpretation of Weinberg's angle. SU(2) gives the anomalous magnetic moments of proton, electron, neutron and generates nuclear range attractive potentials strong enough to produce the binding energies of the deuteron and other nuclides. Lepton and meson masses are due to topological excitations. The geometric mass spectrum is satisfactory. The proton has a triple structure. The alpha constant is a geometric number.

Gustavo R Gonzalez-Martin

2010-07-19T23:59:59.000Z

351

Improving aerosol distributions below clouds by assimilating satellite-retrieved cloud droplet number  

Science Journals Connector (OSTI)

...remainder of the map to the...distributions for mass, number, composition...such as vertical velocity and aerosol composition...updated aerosol mass for each compound...aerosols in trade wind cumulus observed by...spectrum of updraft velocities and the internally...Starting from aerosol mass (M) and number...

Pablo E. Saide; Gregory R. Carmichael; Scott N. Spak; Patrick Minnis; J. Kirk Ayers

2012-01-01T23:59:59.000Z

352

Number | Open Energy Information  

Open Energy Info (EERE)

Number Number Jump to: navigation, search Properties of type "Number" Showing 200 properties using this type. (previous 200) (next 200) A Property:AvgAnnlGrossOpCpcty Property:AvgTempGeoFluidIntoPlant Property:AvgWellDepth B Property:Building/FloorAreaChurchesChapels Property:Building/FloorAreaGroceryShops Property:Building/FloorAreaHealthServices24hr Property:Building/FloorAreaHealthServicesDaytime Property:Building/FloorAreaHeatedGarages Property:Building/FloorAreaHotels Property:Building/FloorAreaMiscellaneous Property:Building/FloorAreaOffices Property:Building/FloorAreaOtherRetail Property:Building/FloorAreaResidential Property:Building/FloorAreaRestaurants Property:Building/FloorAreaSchoolsChildDayCare Property:Building/FloorAreaShops Property:Building/FloorAreaSportCenters

353

Sensitivity of the Simulated Distributions of Water Masses, CFCs, and Bomb 14C to Parameterizations of Mesoscale Tracer Transports in a Model of the North Pacific  

Science Journals Connector (OSTI)

A basinwide ocean general circulation model of the North Pacific Ocean is used to study the sensitivity of the simulated distributions of water masses, chlorofluorocarbons (CFCs), and bomb carbon-14 isotope (14C) to parameterizations of mesoscale ...

Yongfu Xu; Shigeaki Aoki; Koh Harada

2006-03-01T23:59:59.000Z

354

Laser postionization secondary neutral mass spectrometry in tissue: a powerful tool for elemental and molecular imaging in the development of targeted drugs  

Science Journals Connector (OSTI)

...32 Chandra S, Lorey DRI, Smith DR. Quantitative subcellular secondary ion mass spectrometry (SIMS) imaging of boron-10 and boron-11 isotopes in the same cell delivered by two combined BNCT drugs: in vitro studies on human glioblastoma...

Andrea Wittig; Heinrich F. Arlinghaus; Christian Kriegeskotte; Raymond L. Moss; Klaas Appelman; Kurt W. Schmid; Wolfgang A.G. Sauerwein

2008-07-01T23:59:59.000Z

355

Ground-state properties of neutron-rich Mg isotopes  

E-Print Network [OSTI]

We analyze recently-measured total reaction cross sections for 24-38Mg isotopes incident on 12C targets at 240 MeV/nucleon by using the folding model and antisymmetrized molecular dynamics(AMD). The folding model well reproduces the measured reaction cross sections, when the projectile densities are evaluated by the deformed Woods-Saxon (def-WS) model with AMD deformation. Matter radii of 24-38Mg are then deduced from the measured reaction cross sections by ?ne-tuning the parameters of the def-WS model. The deduced matter radii are largely enhanced by nuclear deformation. Fully-microscopic AMD calculations with no free parameter well reproduce the deduced matter radii for 24-36Mg, but still considerably underestimate them for 37,38Mg. The large matter radii suggest that 37,38Mg are candidates for deformed halo nucleus. AMD also reproduces other existing measured ground-state properties (spin-parity, total binding energy, and one-neutron separation energy) of Mg isotopes. Neutron-number (N) dependence of deformation parameter is predicted by AMD. Large deformation is seen from 31Mg with N = 19 to a drip-line nucleus 40Mg with N = 28, indicating that both the N = 20 and 28 magicities disappear. N dependence of neutron skin thickness is also predicted by AMD.

Shin Watanabe; Kosho Minomo; Mitsuhiro Shimada; Shingo Tagami; Masaaki Kimura; Maya Takechi; Mitsunori Fukuda; Daiki Nishimura; Takeshi Suzuki; Takuma Matsumoto; Yoshifumi R. Shimizu; Masanobu Yahiro

2014-04-09T23:59:59.000Z

356

ALARA notes, Number 8  

SciTech Connect (OSTI)

This document contains information dealing with the lessons learned from the experience of nuclear plants. In this issue the authors tried to avoid the `tyranny` of numbers and concentrated on the main lessons learned. Topics include: filtration devices for air pollution abatement, crack repair and inspection, and remote handling equipment.

Khan, T.A.; Baum, J.W.; Beckman, M.C. [eds.] [eds.

1993-10-01T23:59:59.000Z

357

CHROMOSOME NUMBERS IN MAMMALS  

Science Journals Connector (OSTI)

...variables for which the double inte-gral does not exist: R. L. JEFFERY. On the number of elements in a group which have a power in...society will meet at Columbia University, MA ay 2, 1925. W. BENJAMIN FITE Acting Secretary 424 SCIENCE

Theophilus S. Painter

1925-04-17T23:59:59.000Z

358

Baryon Number Violation  

E-Print Network [OSTI]

This report, prepared for the Community Planning Study - Snowmass 2013 - summarizes the theoretical motivations and the experimental efforts to search for baryon number violation, focussing on nucleon decay and neutron-antineutron oscillations. Present and future nucleon decay search experiments using large underground detectors, as well as planned neutron-antineutron oscillation search experiments with free neutron beams are highlighted.

K. S. Babu; E. Kearns; U. Al-Binni; S. Banerjee; D. V. Baxter; Z. Berezhiani; M. Bergevin; S. Bhattacharya; S. Brice; R. Brock; T. W. Burgess; L. Castellanos; S. Chattopadhyay; M-C. Chen; E. Church; C. E. Coppola; D. F. Cowen; R. Cowsik; J. A. Crabtree; H. Davoudiasl; R. Dermisek; A. Dolgov; B. Dutta; G. Dvali; P. Ferguson; P. Fileviez Perez; T. Gabriel; A. Gal; F. Gallmeier; K. S. Ganezer; I. Gogoladze; E. S. Golubeva; V. B. Graves; G. Greene; T. Handler; B. Hartfiel; A. Hawari; L. Heilbronn; J. Hill; D. Jaffe; C. Johnson; C. K. Jung; Y. Kamyshkov; B. Kerbikov; B. Z. Kopeliovich; V. B. Kopeliovich; W. Korsch; T. Lachenmaier; P. Langacker; C-Y. Liu; W. J. Marciano; M. Mocko; R. N. Mohapatra; N. Mokhov; G. Muhrer; P. Mumm; P. Nath; Y. Obayashi; L. Okun; J. C. Pati; R. W. Pattie Jr.; D. G. Phillips II; C. Quigg; J. L. Raaf; S. Raby; E. Ramberg; A. Ray; A. Roy; A. Ruggles; U. Sarkar; A. Saunders; A. Serebrov; Q. Shafi; H. Shimizu; M. Shiozawa; R. Shrock; A. K. Sikdar; W. M. Snow; A. Soha; S. Spanier; G. C. Stavenga; S. Striganov; R. Svoboda; Z. Tang; Z. Tavartkiladze; L. Townsend; S. Tulin; A. Vainshtein; R. Van Kooten; C. E. M. Wagner; Z. Wang; B. Wehring; R. J. Wilson; M. Wise; M. Yokoyama; A. R. Young

2013-11-21T23:59:59.000Z

359

CHEMICAL SAFETY Emergency Numbers  

E-Print Network [OSTI]

- 1 - CHEMICAL SAFETY MANUAL 2010 #12;- 2 - Emergency Numbers UNBC Prince George Campus Security Prince George Campus Chemstores 6472 Chemical Safety 6472 Radiation Safety 5530 Biological Safety 5530 Risk and Safety Manager 5535 Security 7058 #12;- 3 - FOREWORD This reference manual outlines the safe

Bolch, Tobias

360

Searching for isovector signatures in the neutron-rich oxygen and calcium isotopes  

E-Print Network [OSTI]

We search for potential isovector signatures in the neutron-rich oxygen and calcium isotopes within the framework of a relativistic mean-field theory with an exact treatment of pairing correlations. To probe the isovector sector we calibrate a few relativistic density functionals using the same isoscalar constraints but with one differing isovector assumption. It is found that under certain conditions, the isotopic chain in oxygen can be made to terminate at the experimentally observed ${}^{24}$O isotope. In the case of the calcium isotopes, the drip line is predicted to be reached beyond ${}^{60}$Ca. To produce such behavior, the resulting symmetry energy must be soft, with predicted values for the symmetry energy and its slope at saturation density being $J\\!=\\!(30.92\\pm0.47)$ MeV and $L\\!=\\!(51.0\\pm1.5)$ MeV, respectively. As a consequence, the neutron-skin thickness of ${}^{208}$Pb is rather small: $R_{\\rm skin}^{208}\\!=\\!(0.161\\pm0.011)$ fm. This same model - labelled "FSUGarnet" - predicts $R_{1.4}\\!=\\!(13.1\\pm0.1)$ km for the radius of a "canonical" 1.4$M_{\\odot}$ neutron star, yet is also able to support a two-solar-mass neutron star.

Wei-Chia Chen; J. Piekarewicz

2014-12-25T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Isotope Shift Measurements of Stable and Short-Lived Lithium Isotopes for Nuclear Charge Radii Determination  

E-Print Network [OSTI]

Changes in the mean-square nuclear charge radii along the lithium isotopic chain were determined using a combination of precise isotope shift measurements and theoretical atomic structure calculations. Nuclear charge radii of light elements are of high interest due to the appearance of the nuclear halo phenomenon in this region of the nuclear chart. During the past years we have developed a new laser spectroscopic approach to determine the charge radii of lithium isotopes which combines high sensitivity, speed, and accuracy to measure the extremely small field shift of an 8 ms lifetime isotope with production rates on the order of only 10,000 atoms/s. The method was applied to all bound isotopes of lithium including the two-neutron halo isotope Li-11 at the on-line isotope separators at GSI, Darmstadt, Germany and at TRIUMF, Vancouver, Canada. We describe the laser spectroscopic method in detail, present updated and improved values from theory and experiment, and discuss the results.

W. Nörtershäuser; R. Sánchez; G. Ewald; A. Dax; J. Behr; P. Bricault; B. A. Bushaw; J. Dilling; M. Dombsky; G. W. F. Drake; S. Götte; H. -J. Kluge; Th. Kühl; J. Lassen; C. D. P. Levy; K. Pachucki; M. Pearson; M. Puchalski; A. Wojtaszek; Z. -C. Yan; C. Zimmermann

2010-09-02T23:59:59.000Z

362

REPORT OF SURVEY OF OAK RIDGE ISOTOPE  

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

OAK RIDGE ISOTOPE OAK RIDGE ISOTOPE ENRICHMENT (CALUTRON) FACILITY BUILDING 9204-3 U.S. Department of Energy Office of Environmental Management & Office of Nuclear Energy Report of Survey of Oak Ridge Isotope Enrichment (Calutron) Facility Building 9204-3 FINAL May 8, 2000 Contents 1. Introduction 1.1 Purpose 1.2 Facility Description 1.3 Organization Representatives 1.4 Survey Participants 2. Summary, Conclusions & Recommendations 2.1 Transfer Considerations 2.2 Post-Transfer EM Path Forward & Management Risk 3. Survey Results 4. Stabilization and Other Actions Required for Transfer 5. Surveillance & Maintenance After Transfer 6. Other Transfer Details 7. Attachments and References Appendix A - Detailed Survey Notes

363

Isotopic substitution in a model polaronic system  

Science Journals Connector (OSTI)

The effect of isotopic substitution in the excitation spectrum of a model polaronic system is presented. To study this effect we use a three-site many-body Hamiltonian, with two phonon modes, which includes electronic correlations and electron-phonon interactions. Under isotopic substitution, the shift of the lowest excitation energy changes sign for intermediate electron-phonon coupling, coinciding with the onset of polaronic behavior. This manifests as a strong change of the dynamics of polaron tunneling, a behavior opposite to that found in purely phonon excitations. Additionally, a small change in the static polaronic distortion appears under isotopic substitution. This change in the local structure has opposite signs for low and intermediate electron-phonon coupling compared to that found in the strong-coupling limit.

J. Mustre de Leon; R. de Coss; A. R. Bishop; S. A. Trugman

1999-04-01T23:59:59.000Z

364

Apparatus for separating and recovering hydrogen isotopes  

DOE Patents [OSTI]

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.

Heung, Leung K. (Aiken, SC)

1994-01-01T23:59:59.000Z

365

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents [OSTI]

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.

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

1993-01-01T23:59:59.000Z

366

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents [OSTI]

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.

Kronberg, J.W.

1991-05-08T23:59:59.000Z

367

Atomic line emission analyzer for hydrogen isotopes  

DOE Patents [OSTI]

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.

Kronberg, J.W.

1993-03-30T23:59:59.000Z

368

Opportunistic Mass Measurements at the Holifield Radioactive Ion Beam Facility  

SciTech Connect (OSTI)

A technique for measuring mass differences has been developed at the Holifield Radioactive Ion Beam Facility (HRIBF) that requires no specialized equipment. Mass differences are measured as position differences between known and unknown-mass isobars, dispersed at the image of the energy-analyzing magnet following the 25MV tandem post-accelerator, and identified by an energy-loss measurement. The technique has been demonstrated on neutron-rich 77 79Cu and 83 86Ge isotopes produced using the isotope separator online (ISOL) method with the 238U(p,fission) reaction, where a mass accuracy of 500 keV was achieved. These nuclides are well suited to the measurement technique, as they readily migrate out of the production target and to the ion source and comprise the most neutron-rich elements of the isobarically mixed beam. Because modest precision mass values can be obtained with only a few tens of counts of the nuclide of interest among orders of magnitude more of the isobaric neighbors closer to stability, the sensitivity of this technique makes it appropriate for initial mass measurements far from stability.

Hausladen, Paul [ORNL; Beene, James R [ORNL; Galindo-Uribarri, Alfredo {nmn} [ORNL; Larochelle, Y [University of Tennessee, Knoxville (UTK); Liang, J Felix [ORNL; Mueller, Paul Edward [ORNL; Shapira, Dan [ORNL; Stracener, Daniel W [ORNL; Thomas, J. S. [Rutgers University; Varner Jr, Robert L [ORNL; Wollnik, Hermann [ORNL

2006-01-01T23:59:59.000Z

369

Metrics For Comparing Plasma Mass Filters  

SciTech Connect (OSTI)

High-throughput mass separation of nuclear waste may be useful for optimal storage, disposal, or environmental remediation. The most dangerous part of nuclear waste is the fission product, which produces most of the heat and medium-term radiation. Plasmas are well-suited to separating nuclear waste because they can separate many different species in a single step. A number of plasma devices have been designed for such mass separation, but there has been no standardized comparison between these devices. We define a standard metric, the separative power per unit volume, and derive it for three different plasma mass filters: the plasma centrifuge, Ohkawa filter, and the magnetic centrifugal mass filter. __________________________________________________

Abraham J. Fetterman and Nathaniel J. Fisch

2012-08-15T23:59:59.000Z

370

Report of Survey of Oak Ridge Isotope Enrichment (Calutron) Facility...  

Office of Environmental Management (EM)

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

371

Isotope effects in methanol synthesis and the reactivity of copper...  

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

Isotope effects in methanol synthesis and the reactivity of copper formates on a CuSiO2 catalyst. Isotope effects in methanol synthesis and the reactivity of copper formates on a...

372

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

Open Energy Info (EERE)

gas abundances and isotopic compositions. The helium isotopic compositions of fluids produced from the Dixie Valley geothermal field range from 0.70 to 0.76 Ra, are among the...

373

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

374

ELECTRICAL DISTRICT NUMBER EIGHT  

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

ELECTRICAL DISTRICT NUMBER EIGHT ELECTRICAL DISTRICT NUMBER EIGHT Board of Directors Reply to: Ronald Rayner C. W. Adams James D. Downing, P.E. Chairman Billy Hickman 66768 Hwy 60 Brian Turner Marvin John P.O. Box 99 Vice-Chairman Jason Pierce Salome, AZ 85348 Denton Ross Jerry Rovey Secretary James N. Warkomski ED8@HARCUVARCO.COM John Utz Gary Wood PHONE:(928) 859-3647 Treasurer FAX: (928) 859-3145 Sent via e-mail Mr. Darrick Moe, Regional Manager Western Area Power Administration Desert Southwest Region P. O. Box 6457 Phoenix, AZ 85005-6457 moe@wapa.gov; dswpwrmrk@wapa.gov Re: ED5-Palo Verde Hub Project Dear Mr. Moe, In response to the request for comments issued at the October 6 Parker-Davis Project customer th meeting, and in conjunction with comments previously submitted by the Southwest Public Power

375

Preventive Action Number:  

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

8 Preventive Action Report Planning Worksheet 11_0414 1 of 3 8 Preventive Action Report Planning Worksheet 11_0414 1 of 3 EOTA - Business Form Document Title: Preventive Action Report Planning Worksheet Document Number: F-018 Rev 11_0414 Document Owner: Elizabeth Sousa Backup Owner: Melissa Otero Approver(s): Melissa Otero Parent Document: P-008, Corrective/Preventive Action Notify of Changes: EOTA Employees Referenced Document(s): N/A F-018 Preventive Action Report Planning Worksheet 11_0414 2 of 3 Revision History: Rev. Description of Change 08_0613 Initial Release 09_0924 Worksheet modified to reflect External Audit recommendation for identification of "Cause for Potential Nonconformance". Minor editing changes. 11_0414 Added Preventive Action Number block to match Q-Pulse

376

Preventive Action Number:  

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

7 Corrective Action Report Planning Worksheet 11_0414 1 of 3 7 Corrective Action Report Planning Worksheet 11_0414 1 of 3 EOTA - Business Form Document Title: Corrective Action Report Planning Worksheet Document Number: F-017 Rev 11_0414 Document Owner: Elizabeth Sousa Backup Owner: Melissa Otero Approver(s): Melissa Otero Parent Document: P-008, Corrective/Preventive Action Notify of Changes: EOTA Employees Referenced Document(s): N/A F-017 Corrective Action Report Planning Worksheet 11_0414 2 of 3 Revision History: Rev. Description of Change 08_0613 Initial Release 11_0414 Added problem statement to first block. F-017 Corrective Action Report Planning Worksheet 11_0414 3 of 3 Corrective Action Report Planning Worksheet Corrective Action Number: Source: Details/Problem Statement: Raised By: Raised Date: Target Date:

377

Mass Spectrometer: Orbitrap | EMSL  

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

Software (ISIS): A Machine Learning Approach to Tandem Mass Spectral Identification of Lipids. Liquid chromatography-mass spectrometry-based metabolomics has gained importance...

378

Mass Spectrometry | EMSL  

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

and Microfabrication Mass Spectrometry Microscopy Molecular Science Computing NMR and EPR Spectroscopy and Diffraction Subsurface Flow and Transport Mass Spectrometry Systems...

379

CARBONATE STABLE ISOTOPES | Terrestrial Teeth and Bones  

Science Journals Connector (OSTI)

Teeth and bones of fossil vertebrates can preserve a record of Quaternary terrestrial environments in the form of isotopic compositions of carbon (13C/12C), nitrogen (15N/14N), and oxygen (18O/16O). These isotopic signatures in teeth and bones have yielded valuable information on the extent of savanna environments under tropical climates, on the ancient levels of aridity, on the spread of dense forests at the beginning of the Holocene, and on the paleodiet of hominids and their associated fauna.

H. Bocherens; D.G. Drucker

2007-01-01T23:59:59.000Z

380

CARBONATE STABLE ISOTOPES | Terrestrial Teeth and Bones  

Science Journals Connector (OSTI)

Abstract Teeth and bones of fossil vertebrates can preserve a record of Quaternary terrestrial environments in the form of the isotopic compositions of carbon (13C/12C), nitrogen (15N/14N), and oxygen (18O/16O). These isotopic signatures in teeth and bones have yielded valuable information on the extent of savanna environments under tropical climates, on the ancient levels of aridity, on the spread of dense forests at the beginning of the Holocene, and on the paleodiet of Hominids and their associated fauna.

H. Bocherens; D.G. Drucker

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Isotopic abundance in atom trap trace analysis  

DOE Patents [OSTI]

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.

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

2014-03-18T23:59:59.000Z

382

Novel Gas Isotope Interpretation Tools to Optimize Gas Shale  

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

Final Report to Final Report to Report Number 08122.15.Final Novel Gas Isotope Interpretation Tools to Optimize Gas Shale Production Contract: 08122-15 Principal Investigator: William A. Goddard, III Title: Director, Materials and Process Simulation Center California Institute of Technology Wag@wag.caltech.edu Co-PIs: Yongchun Tang, Ph.D. Title: Director, Power Environmental Energy Research Institute Other Author(s) Sheng Wu, Ph.D Andrew Deev, Ph.D Qisheng Ma, Ph.D Gao Li, Ph.D. June 5, 2013 2 LEGAL NOTICE This report was prepared by California Institute of Technology as an account of work sponsored by the Research Partnership to Secure Energy for America, RPSEA. Neither RPSEA members of RPSEA, the National Energy Technology Laboratory, the U.S. Department of Energy, nor any person acting on behalf of

383

Boson effective charges for light Se, Kr, and Sr isotopes  

Science Journals Connector (OSTI)

A consistent analysis of E2 transition probabilities for nine neutron-deficient even-even Se, Kr, and Sr isotopes has been performed, based on previous parametrizations for these nuclei within the proton-neutron interacting-boson model, from which boson effective charges e? and e? are deduced. Two sets of effective charges are obtained, one set having e??e? for most of the nuclei studied, and the other set having e? substantially larger than e? for most of the nuclei. For both sets, e? tends to decrease with increasing neutron number, while e? is roughly constant. More information on mixed-symmetry states is needed to determine which set is valid.

A. F. Barfield and K. P. Lieb

1990-04-01T23:59:59.000Z

384

Equilibrium Isotope Effect for Hydrogen Absorption in Palladium  

Science Journals Connector (OSTI)

The method using addition of isotopes to the system in sequence to investigate isotope exchange effects has not been previously reported. ... (1) A simple model was proposed(1) that described the dependence of the desorption plateau pressure on a linear combination of the isotopic fractions in the solid and the plateau pressures of the single-isotope?Pd systems; that is, H?Pd and D?Pd. ...

Weifang Luo; Donald F. Cowgill; Rion A. Causey

2009-10-21T23:59:59.000Z

385

Isotopic Enrichment of Tritiated Water by a Bipolar Electrolysis Process  

Science Journals Connector (OSTI)

Isotope Separation / Proceedings of the Sixth International Conference on Tritium Science and Technology Tsukuba, Japan November 12-16, 2001

S. Heinze; D. Ducret; J.-P. Verdin; T. Pelletier

386

Isotopic Analysis- Gas At Dixie Valley Geothermal Area (Kennedy...  

Open Energy Info (EERE)

search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Gas At Dixie Valley Geothermal Area (Kennedy & Soest, 2006) Exploration Activity Details...

387

Final Report on Isotope Ratio Techniques for Light Water Reactors  

SciTech Connect (OSTI)

The Isotope Ratio Method (IRM) 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.

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

2009-07-01T23:59:59.000Z

388

Isotope Fractionation of Water during Evaporation without Condensation  

Science Journals Connector (OSTI)

Specifially, isotope fractionation factors associated with free evaporation (?evap) have been measured as a function of the isotopic composition and temperature of the liquid. ... Liquid-vapor fractionation of oxygen and hydrogen isotopes of water from the freezing to the critical temperature ...

Christopher D. Cappa; Walter S. Drisdell; Jared D. Smith; Richard J. Saykally; Ronald C. Cohen

2005-12-03T23:59:59.000Z

389

Discovery of Rubidium, Strontium, Molybdenum, and Rhodium Isotopes  

E-Print Network [OSTI]

Currently, thirty-one rubidium, thirty-five strontium, thirty-five molybdenum and thirty-eight rhodium 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.

Parker, A M

2011-01-01T23:59:59.000Z

390

Discovery of rubidium, strontium, molybdenum, and rhodium isotopes  

SciTech Connect (OSTI)

Currently, 31 rubidium, 35 strontium, 35 molybdenum, and 38 rhodium 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.

Parker, A.M.; Thoennessen, M., E-mail: thoennessen@nscl.msu.edu

2012-07-15T23:59:59.000Z

391

Discovery of Rubidium, Strontium, Molybdenum, and Rhodium Isotopes  

E-Print Network [OSTI]

Currently, thirty-one rubidium, thirty-five strontium, thirty-five molybdenum and thirty-eight rhodium 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.

A. M. Parker; M. Thoennessen

2011-02-11T23:59:59.000Z

392

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

393

Isotope Explorer Users Manual S.Y.F. Chu*  

E-Print Network [OSTI]

Transfer B. Data from Local Disk or the Table of Isotopes CD-ROM C. Isotope Explorer as Helper Application disk (e.g. from the Table of Isotopes CD-ROM). The ENSDF database on the 1999 update CD-ROM

394

Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes  

E-Print Network [OSTI]

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.

May, E

2011-01-01T23:59:59.000Z

395

Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes  

E-Print Network [OSTI]

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.

E. May; M. Thoennessen

2011-09-08T23:59:59.000Z

396

Colorado Natural Gas Number of Residential Consumers (Number...  

Gasoline and Diesel Fuel Update (EIA)

Residential Consumers (Number of Elements) Colorado Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

397

Colorado Natural Gas Number of Industrial Consumers (Number of...  

Gasoline and Diesel Fuel Update (EIA)

Industrial Consumers (Number of Elements) Colorado Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

398

Colorado Natural Gas Number of Commercial Consumers (Number of...  

Gasoline and Diesel Fuel Update (EIA)

Commercial Consumers (Number of Elements) Colorado Natural Gas Number of Commercial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

399

NAME: STUDENT NUMBER (PID): CITY, STATE ZIP: DAYTIME PHONE NUMBER  

E-Print Network [OSTI]

NAME: STUDENT NUMBER (PID): ADDRESS: CITY, STATE ZIP: DAYTIME PHONE NUMBER: CELL PHONE NUMBER of financial institution. 14 Cell Phone Expenses 15 Other ordinary and necessary living expenses. 16 TOTAL (add

400

Connecticut Natural Gas Number of Residential Consumers (Number...  

Gasoline and Diesel Fuel Update (EIA)

Residential Consumers (Number of Elements) Connecticut Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6...

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Connecticut Natural Gas Number of Commercial Consumers (Number...  

Gasoline and Diesel Fuel Update (EIA)

Commercial Consumers (Number of Elements) Connecticut Natural Gas Number of Commercial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

402

Connecticut Natural Gas Number of Industrial Consumers (Number...  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Industrial Consumers (Number of Elements) Connecticut Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

403

Concentrations and activity ratios of uranium isotopes in groundwater from Donana National Park, South of Spain  

SciTech Connect (OSTI)

The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Donana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and {sup 210}Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that {sup 234}U/{sup 238}U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer.

Bolivar, J. P.; Olias, M.; Gonzalez-Garcia, F. [Department of Applied Physics, University of Huelva, Campus de El Carmen, 21071-Huelva (Spain); Garcia-Tenorio, R. [Department of Applied Physics II, University of Sevilla, ETSA Arquitectura, 41012-Sevilla (Spain)

2008-08-07T23:59:59.000Z

404

The graphene phonon dispersion with C{sup 12} and C{sup 13} isotopes  

SciTech Connect (OSTI)

Using very uniform large scale chemical vapor deposition grown graphene transferred onto silicon, we were able to identify 15 distinct Raman lines associated with graphene monolayers. This was possible thanks to a combination of different carbon isotopes and different Raman laser energies and extensive averaging without increasing the laser power. This allowed us to obtain a detailed experimental phonon dispersion relation for many points in the Brillouin zone. We further identified a D+D' peak corresponding to a double phonon process involving both an inter- and intra-valley phonon. In order to both eliminate substrate effects and to probe large areas, we undertook to study Raman scattering for large scale chemical vapor deposition (CVD) grown graphene using two different isotopes (C12 and C13) so that we can effectively exclude and subtract the substrate contributions, since a heavier mass downshifts only the vibrational properties, while keeping all other properties the same.

Whiteway, Eric; Bernard, Simon; Yu, Victor; Hilke, Michael [Department of Physics, McGill University, Montréal H3A 2T8 (Canada); Austing, D. Guy [National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada)

2013-12-04T23:59:59.000Z

405

Mass spectrometric immunoassay  

DOE Patents [OSTI]

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Nelson, Randall W; Williams, Peter; Krone, Jennifer Reeve

2013-07-16T23:59:59.000Z

406

Mass spectrometric immunoassay  

DOE Patents [OSTI]

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Nelson, Randall W (Phoenix, AZ); Williams, Peter (Phoenix, AZ); Krone, Jennifer Reeve (Granbury, TX)

2007-12-04T23:59:59.000Z

407

Radioactive isotopes in Danish drinking water  

E-Print Network [OSTI]

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

408

Review of hydrogen isotope permeability through materials  

SciTech Connect (OSTI)

This report is the first part of a comprehensive summary of the literature on hydrogen isotope permeability through materials that do not readily form hydrides. While we mainly focus on pure metals with low permeabilities because of their importance to tritium containment, we also give data on higher-permeability materials such as iron, nickel, steels, and glasses.

Steward, S.A.

1983-08-15T23:59:59.000Z

409

Mikhail Avilov Facility for Rare Isotope Beams  

E-Print Network [OSTI]

Challenges Chemical Challenges Radiation Challenges Summary #12; World-leading heavy ion accelerator facility for rare isotope science · Nuclear Structure · Nuclear Astrophysics · Fundamental Interactions Target vacuum vessel M. Avilov, May 2014 5th HP Targetry Workshop, FNAL, Slide 4 Target Beam dump Beam

McDonald, Kirk

410

Gauge Fields, Sources, and Electromagnetic Masses  

Science Journals Connector (OSTI)

The hypothesis of strong-interaction gauge fields, with non-Abelian gauge invariance broken only by the 1- particle mass terms, gives a natural source theory setting for the introduction of electromagnetic effects. The electromagnetic potential vector appears as a compensating field in the mass terms of the neutral 1- particles. The resulting electromagnetic self-action is used to discuss mass displacements. The pion electro-magnetic mass is computed in a number of ways—by direct calculation of various processes and by chiral methods, in two variants. The relationship of these approaches is established. A phenomenological modification of the chiral evaluation gives perfect agreement with the observed value. It is found, however, that the (m?m?)2 terms, which are neglected in this method, are not very small. Baryon electromagnetic mass splittings are described by a simple adaptation of gross mass-spectrum empirics. Agreement with the data is excellent.

Julian Schwinger

1968-01-25T23:59:59.000Z

411

Carbon IsotopesCarbon Isotopes A Short Course VU March, 2009  

E-Print Network [OSTI]

. Historical CO2 record from the Vostok ice core. In Trends: A Compendium of Data on Global Change. Carbon · Bitumen · Coal Range of Carbon Isotopes PDB Hoefs 1982 #12;2/25/2009 3 Range of Carbon Isotopes PDB Hoefs 1982 12CO2 Photosynthesis 12CO2 Respiration 13CO2 CO2+ RUBP = PGA (=27) RUBISCO #12;2/25/2009 4

Miami, University of

412

Validation of Electrochemically Modulated Separations Performed On-Line with MC-ICP-MS for Uranium and Plutonium Isotopic Analyses  

SciTech Connect (OSTI)

The most time consuming process in uranium or plutonium isotopic analyses is performing the requisite chromatographic separation of the actinides. Filament preparation for thermal ionization (TIMS) adds further delays, but is generally accepted due to the unmatched performance in trace isotopic analyses. Advances in Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS) are beginning to rival the performance of TIMS. Methods, such as Electrochemically Modulated Separations (EMS) can efficiently pre-concentrate U or Pu quite selectively from small solution volumes in a matrix of 0.5 M nitric acid. When performed in-line with ICP-MS, the rapid analyte release from the electrode is fast, and large transient analyte signal enhancements of >100 fold can be achieved as compared to more conventional continuous nebulization of the original starting solution. This makes the approach ideal for very low level isotope ratio measurements. In this paper, some aspects of EMS performance are described. These include low level Pu isotope ratio behavior versus concentration by MC-ICP-MS and uranium rejection characteristics that are also important for reliable low level Pu isotope ratio determinations.

Liezers, Martin; Olsen, Khris B.; Mitroshkov, Alexandre V.; Duckworth, Douglas C.

2010-08-11T23:59:59.000Z

413

Configuration splitting of the Gamow-Teller resonance in antimony isotopes: Is this a real or a virtual effect?  

SciTech Connect (OSTI)

The Gamow-Teller strength functions for a number of antimony isotopes were calculated within a semimicroscopic approach based on the continuum version of the charge-exchange quasiparticle random-phase approximation and on phenomenologically taking into account the fragmentation effect. The structural effect of splitting of the main maximum of the Gamow-Teller resonance in these isotopes was confirmed. Experimental data on the excitation of this resonance in a direct and a resonance reaction for the {sup 118}Sn parent nucleus were analyzed with allowance for this effect.

Igashov, S. Yu., E-mail: igashov@theor.mephi.ru [All-Russia Research Institute of Automatics (Russian Federation); Rodin, V. A. [Institut fuer theoretische Physik der Universitaet Tuebingen (Germany)] [Institut fuer theoretische Physik der Universitaet Tuebingen (Germany); Urin, M. H. [National Research Nuclear University MEPhI (Russian Federation)] [National Research Nuclear University MEPhI (Russian Federation)

2013-04-15T23:59:59.000Z

414

MAGNESIUM ISOTOPE EVIDENCE FOR SINGLE STAGE FORMATION OF CB CHONDRULES BY COLLIDING PLANETESIMALS  

SciTech Connect (OSTI)

Chondrules are igneous spherical objects preserved in chondritic meteorites and believed to have formed during transient heating events in the solar protoplanetary disk. Chondrules present in the metal-rich CB chondrites show unusual chemical and petrologic features not observed in other chondrite groups, implying a markedly distinct formation mechanism. Here, we report high-precision Mg-isotope data for 10 skeletal olivine chondrules from the Hammadah al Hamra 237 (HH237) chondrite to probe the formation history of CB chondrules. The {sup 27}Al/{sup 24}Mg ratios of individual chondrules are positively correlated to their stable Mg-isotope composition (?{sup 25}Mg), indicating that the correlated variability was imparted by a volatility-controlled process (evaporation/condensation). The mass-independent {sup 26}Mg composition (?{sup 26}Mg*) of chondrules is consistent with single stage formation from an initially homogeneous magnesium reservoir if the observed ?{sup 25}Mg variability was generated by non-ideal Rayleigh-type evaporative fractionation characterized by a ? value of 0.5142, in agreement with experimental work. The magnitude of the mass-dependent fractionation (?300 ppm) is significantly lower than that suggested by the increase in {sup 27}Al/{sup 24}Mg values, indicating substantial suppression of isotopic fractionation during evaporative loss of Mg, possibly due to evaporation at high Mg partial pressure. Thus, the Mg-isotope data of skeletal chondrules from HH237 are consistent with their origin as melts produced in the impact-generated plume of colliding planetesimals. The inferred ?{sup 26}Mg* value of –3.87 ± 0.93 ppm for the CB parent body is significantly lower than the bulk solar system value of 4.5 ± 1.1 ppm inferred from CI chondrites, suggesting that CB chondrites accreted material comprising an early formed {sup 26}Al-free component.

Olsen, Mia B.; Schiller, Martin; Krot, Alexander N.; Bizzarro, Martin [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Copenhagen DK-1350 (Denmark)] [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Copenhagen DK-1350 (Denmark)

2013-10-10T23:59:59.000Z

415

Method of enhancing selective isotope desorption from metals  

DOE Patents [OSTI]

A method of enhancing the thermal desorption of a first isotope of a diatomic gas from a metal comprises the steps of (a) establishing a partial pressure of a second isotope of the diatomic gas in vicinity of the metal; heating the metal to a temperature such that the first isotope is desorbed from the metal; and reducing the partial pressure of the desorbed first isotope while maintaining the partial pressure of the second isotope substantially constant. The method is especially useful for enhancing the desorption of tritium from the Zr-Al getter in a plasma confinement device.

Knize, Randall J. (Plainsboro, NJ); Cecchi, Joseph L. (Lawrenceville, NJ)

1984-01-01T23:59:59.000Z

416

Construction Project Number  

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

North Execution - (2009 - 2011) North Execution - (2009 - 2011) Construction Project Number 2009 2010 2011 Project Description ANMLPL 0001C 76,675.32 - - Animas-Laplata circuit breaker and power rights CRGRFL 0001C - - 7,177.09 Craig Rifle Bay and transfer bay upgrade to 2000 amps; / Convert CRG RFL to 345 kV out of Bears Ear Sub FGE 0019C - - 39,207.86 Replace 69/25kV transformer KX2A at Flaming Gorge FGE 0020C - - 52,097.12 Flaming Gorge: Replace failed KW2A transformer HDN 0069C 16,638.52 208,893.46 3,704,578.33 Replace failed transformer with KZ1A 250 MVA 230/138kv

417

KPA Activity Number  

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

supports CMM-SW Level 2 supports CMM-SW Level 2 Mapping of the DOE Systems Engineering Methodology to the Software Engineering Institute (SEI) Software Capability Maturity Model (CMM- SW) level 2. Date: September 2002 Page 1 KPA Activity Number KPA Activity SEM Section SME Work Product SQSE Web Site http://cio.doe.gov/sqse REQUIREMENTS MANAGEMENT RM-1 The software engineering group reviews the allocated requirements before they are incorporated in the software project. Chapter 3.0 * Develop High-Level Project Requirements Chapter 4.0 * Establish Functional Baseline * Project Plan * Requirements Specification Document * Requirements Management awareness * Defining Project Requirements RM-2 The software engineering group uses the allocated requirements as the basis for

418

Physics with Rare Isotope Beams  

SciTech Connect (OSTI)

Using stable and radioactive beams provided by ATLAS nuclear reactions of special interest in astrophysics have been studied with emphasis on breakout from the hot CNO cycle to the rp-process. The masses of nuclear fragments provided by a strong fission source have been measured in order to help trace the path of the r process. 8Li ions produced by the d(7Li,8Li)n reaction have been trapped and the electrons and alphas emitted in the ensuing beta-decay measured. The neutrino directions were therefore determined, which leads to a measurement of the electron-neutrino correlation. The energies and kinematics are such that a sensitive search for any tensor admixture could be performed and an upper limit of 0.6% was placed on any such admixture. Earlier work on the electromagnetic form factors of the proton was extended. Graduate students were active participants in all of these eperiments, which formed the basis for six PhD theses.

Segel, Ralph E. [Northwestern University] [Northwestern University

2013-11-08T23:59:59.000Z

419

Isotopic Analysis At Dixie Valley Geothermal Field Area (Laney, 2005) |  

Open Energy Info (EERE)

Isotopic Analysis At Dixie Valley Geothermal Field Area (Laney, 2005) Isotopic Analysis At Dixie Valley Geothermal Field Area (Laney, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Dixie Valley Geothermal Field Area (Laney, 2005) Exploration Activity Details Location Dixie Valley Geothermal Field Area Exploration Technique Isotopic Analysis- Fluid Activity Date Usefulness not indicated DOE-funding Unknown Notes Gas and Isotopes Geochemistry, Kennedy, van Soest and Shevenell. During FY04, we concentrated on two primary projects. The first was a detailed study of helium isotope systematics throughout Dixie Valley and the inter-relationship between the Dixie Valley geothermal reservoir and local hydrology. The second is the construction of a helium isotope "map" of the

420

Method of preparing mercury with an arbitrary isotopic distribution  

DOE Patents [OSTI]

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.

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

1986-12-16T23:59:59.000Z

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Method of preparing mercury with an arbitrary isotopic distribution  

DOE Patents [OSTI]

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.

Grossman, Mark W. (Belmont, MA); George, William A. (Rockport, MA)

1986-01-01T23:59:59.000Z

422

Comment on 'Existence of long-lived isomeric states in naturally-occurring neutron-deficient Th isotopes'  

SciTech Connect (OSTI)

In their article ''Existence of Long-Lived Isomeric States in Naturally-Occuring Neutron-Deficient Th Isotopes''[Phys. Rev. C 76, 021303 (2007)], Marinov et al. fail to demonstrate that basic mass spectrometric protocols, such as abundance sensitivity, linearity, and freedom from possible interferences, have been met. In particular, the claim that four isomeric states of Th have been discovered, using an inductively coupled plasma-sector field mass spectrometer (ICP-SFMS), with abundances from (1-10)x10{sup -11} relative to {sup 232}Th, cannot be accepted, given the known abundance sensitivities of other sector field mass spectrometers. Accelerator mass spectrometry is the only mass spectrometric methodology capable of measuring relative abundances of the magnitude claimed by Marinov et al.

Barber, R. C.; De Laeter, J. R. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Department of Applied Physics, Curtin University, Perth, Western Australia (Australia)

2009-04-15T23:59:59.000Z

423

Composition of nanoparticles in optical fibers by Secondary Ion Mass Spectrometry  

E-Print Network [OSTI]

encapsulate LI to produce « engineered » spectroscopic properties. To determine the composition of DNP-SIMS investigation of boron distribution in steels," Surf. Interface Anal. 43, 573-575 (2011). 12. C. Lechene, F imaging of mammalian and bacterial cells using stable isotope mass spectrometry," Journal of Biology 5, 20

Boyer, Edmond

424

Fission product studies in the symmetric mass region  

SciTech Connect (OSTI)

Fission yields can be determined by radiochemical or mass spectrometric techniques. Mass spectrometry can provide more accurate data, particularly in the symmetric mass region where the probability of fission is low and uncertainties in isometric ratios occur. Fine structure in the mass distribution can usually only be determined by mass spectrometry. Many of the elements in the valley of symmetry have high ionization potentials and are therefore difficult to measure by solid source mass spectrometry. Analytical techniques have been developed to provide the sensitivity required to measure the small sample sizes available in fission product studies. Cumulative fission yields for ruthenium, palladium, cadmium, tin, and tellurium have been measured by mass spectrometry for the thermal and epicadmium fission of {sup 233}U and for thermal and epicadmium fission of {sup 239}Pu. These fission yields, which span the mass range 101 {le} A {le} 130, can be combined to give a mass yield curve for {sup 235}U in the valley region, which is symmetrical about A = 116.8 and exhibits fine structure in the mass 113 to 114 region. Fine structure in {sup 233}U is also present at mass 111. Mass spectrometric determinations of the fission yields of uranium ore at the Oklo mine site in Gabon enable the nuclear parameters of this natural reactor to be evaluated. This in turn enables the amounts of fission products produced in the reactor zone and the surrounding rocks enables an assessment to be made of the efficiency of this geological repository for containing radioactive waste. The elemental abundances can be determined by isotope dilution mass spectrometry. Unfortunately, the paucity of good fission yield data available for {sup 238}U by fast neutrons is a severe constraint in this evaluation.

De Laeter, J.R.; Rosman, K.J.R.; Loss, R.D. [Curtin Univ. of Technology, Perth (AU)

1993-05-01T23:59:59.000Z

425

Isotope selective near-resonant two-photon ionization of 41Ca isotope via the 4s11s 1S0 intermediate state  

Science Journals Connector (OSTI)

Isotope selective excitation of a 41Ca isotope using a near-resonant two-photon ionization scheme 4s2 1S0-->422.7924...

Sankari, M

2008-01-01T23:59:59.000Z

426

Diffusion of Kr Isotopes in Solid Ar  

Science Journals Connector (OSTI)

The diffusion coefficient D=D0e-Q0RT and isotope effect for Kr78 and Kr86 in solid Ar have been measured using a tracer technique. The activation energy QKr0 depends on the interchange parameter w, but is estimated to lie in the range 3500-3900 cal mole-1, with the most reliable w giving the lower value. Thus, the two calculated QKr0 (3853 and 4050 cal mole-1) for the vacancy mechanism using a two-body (12, 6) potential appear somewhat high, but in reasonable agreement with experiment. The isotope effect gives f?K?(D78D86-1)[(8678)12-1]=0.48±0.25 which, since QKr0?QAr0, suggests that ?K?0.6 for a single-vacancy mechanism. {Here f is the correlation factor and ?K?(?278?286-1)[(8678)12-1], where ?2 is the tracer jump rate.}

E. H. C. PARKER; B. L. SMITH; H. R. GLYDE

1969-12-15T23:59:59.000Z

427

Nuclear sizes and the isotope shift  

Science Journals Connector (OSTI)

Darwin-Foldy nuclear-size corrections in electronic atoms and nuclear radii are discussed from the nuclear-physics perspective. The interpretation of precise isotope-shift measurements is formalism dependent, and care must be exercised in interpreting these results and those obtained from relativistic electron scattering from nuclei. We strongly advocate that the entire nuclear-charge operator be used in calculating nuclear-size corrections in atoms rather than relegating portions of it to the nonradiative recoil corrections. A preliminary examination of the intrinsic deuteron radius obtained from isotope-shift measurements suggests the presence of small meson-exchange currents (exotic binding contributions of relativistic order) in the nuclear charge operator, which contribute approximately 12%.

J. L. Friar; J. Martorell; D. W. L. Sprung

1997-12-01T23:59:59.000Z

428

High-purity, isotopically enriched bulk silicon  

SciTech Connect (OSTI)

The synthesis and characterization of dislocation-free, undoped, single crystals of Si enriched in all 3 stable isotopes is reported: {sup 28}Si (99.92%), {sup 29}Si (91.37%), and {sup 30}Si (89.8%). A silane-based process compatible with the relatively small amounts of isotopically enriched precursors that are practically available was used. The silane is decomposed to silicon on a graphite starter rod heated to 700-750 C in a recirculating flow reactor. A typical run produces 35 gm of polycrystalline Si at a growth rates of 5 {micro}m/min and conversion efficiency >95%. Single crystals are grown by the floating zone method and characterized by electrical and optical measurements. Concentrations of shallow dopants (P and B) are as low as mid-10{sup 13} cm{sup -3}. Concentrations of C and O lie below 10{sup 16} and 10{sup 15} cm{sup -3}, respectively.

Ager III, J.W.; Beeman, J.W.; Hansen, W.L.; Haller, E.E.; Sharp, I.D.; Liao, C.; Yang, A.; Thewalt, M.L.W.; Riemann, H.

2004-11-17T23:59:59.000Z

429

EMSL - Mass Spectrometry  

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

mass-spectrometry Proteomics Capabilities High resolution and mass accuracy Fourier-transform ion cyclotron resonance (FT-ICR) spectrometers, from 6 Tesla (T) to 15T and 21T in...

430

mass communication advertising &  

E-Print Network [OSTI]

mass communication advertising & public relations introduction. Graduate programs in the Department of Mass Communication, Advertising, and Public Relations provide an entry to a wide spectrum of careers the opportunity to create content, campaigns, strategy, and research in public relations, advertising

Finzi, Adrien

431

Diffusional exchange of isotopes in a metal hydride sphere.  

SciTech Connect (OSTI)

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.

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

2011-04-01T23:59:59.000Z

432

In situ LA–MC–ICP–MS boron isotope and zircon U–Pb age determinations of Paleoproterozoic borate deposits in Liaoning Province, northeastern China  

Science Journals Connector (OSTI)

Abstract A large number of Paleoproterozoic borate deposits are hosted by the lower units of a volcanic-sedimentary sequence in Liaoning Province, northeastern China, and are a major source of boron in China. The ore-bearing wall rocks in the deposits are serpentinized ultrabasic rocks and carbonates, with layered leptynites, leptites, amphibolites, and migmatites adjacent to the ore. Both the borate ores and country rocks contain tourmaline, although the country rocks have much lower abundances of the mineral. Based on in situ boron isotope measurements using laser ablation–multi-collector–inductively coupled plasma–mass spectrometry (LA–MC–ICP–MS), boron isotope data show that: (1) ?11B values of borate ores range from + 6.8‰ to + 13.9‰ (mean + 10.8‰); (2) tourmalines from the borate ores have ?11B values from + 9.5‰ to + 12.7‰; and (3) the wall rocks within the borate ores yield slightly lower ?11B values ranging from + 5.7‰ to + 7.6‰, and those outside the deposits from ? 9.9‰ to ? 5.9‰. Positive ?11B values in borates as well as in tourmalines inside the mining area indicate that boron in these Paleoproterozoic borate deposits was derived from marine evaporites. ?34SV-CDT (where V-CDT is Vienna Canyon Diablo Troilite) values of borate ores, serpentinized marbles, and anhydrites range from + 16.1‰ to + 24.7‰, whereas ?13CV-PDB (where V-PDB is Vienna Pee Dee Belemnite) values of marbles range from + 3.2‰ to + 5.9‰. These isotopic characteristics are interpreted to reflect formation in a marine evaporative environment. LA–MC–ICP–MS zircon weighted207Pb/206Pb ages of leptite and serpentinized olivine basalt from the hanging wall of the borate deposits are 2139 ± 13 Ma and 2130 ± 19 Ma, respectively. Therefore, the (~ 2.2 Ga) borate deposits may have originated from marine evaporative boron-bearing sediments, which were interbedded within bimodal volcanic rocks during the early stages of development of the Liaoji rift.

Guyue Hu; Yanhe Li; Changfu Fan; Kejun Hou; Yue Zhao; Lingsen Zeng

2014-01-01T23:59:59.000Z

433

High Flux Isotope Reactor power upgrade status  

SciTech Connect (OSTI)

A return to 100-MW operation is being planned for the High Flux Isotope Reactor (HFIR). Recent improvements in fuel element manufacturing procedures and inspection equipment will be exploited to reduce hot spot and hot streak factors sufficiently to permit the power upgrade without an increase in primary coolant pressure. Fresh fuel elements already fabricated for future use are being evaluated individually for power upgrade potential based on their measured coolant channel dimensions.

Rothrock, R.B.; Hale, R.E. [Oak Ridge National Lab., TN (United States); Cheverton, R.D. [Delta-21 Resources Inc., Oak Ridge, TN (United States)

1997-03-01T23:59:59.000Z

434

Sulfur-isotope separation by distillation  

SciTech Connect (OSTI)

Sulfur-isotope separation by low-temperature distillation of hydrogen sulfide was studied in an 8-m, 25-mm diameter distillation column. Column temperature was controlled by a propane-propylene heat pipe. Column packing HETP was measured using nitric oxide in the column. The column was operated at pressures from 45 to 125 kPa. The relative volatility of S-32 vs. S-34 varied from 1.0008 to 1.0014.

Mills, T.R.

1982-01-01T23:59:59.000Z

435

Concerning the Facility for Rare Isotope Beams  

ScienceCinema (OSTI)

James Symons, Nuclear Science Division Director at Lawrence Berkeley Lab, and Daniela Leitner, head of operations at Berkeley Lab's 88-Inch Cyclotron, discuss major contributions to the new Facility for Rare Isotope Beams (FRIB) at Michigan State University, including ion source, which will based on the VENUS source built for the 88-Inch Cyclotron, and the GRETA gamma-ray detector now under construction there.

Symons, James

2013-05-29T23:59:59.000Z

436

Augmenting real data with synthetic data: an application in assessing radio-isotope identification algorithms  

SciTech Connect (OSTI)

The performance of Radio-Isotope Identification (RIID) algorithms using gamma spectroscopy is increasingly important. For example, sensors at locations that screen for illicit nuclear material rely on isotope identification to resolve innocent nuisance alarms arising from naturally occurring radioactive material. Recent data collections for RIID testing consist of repeat measurements for each of several scenarios to test RIID algorithms. Efficient allocation of measurement resources requires an appropriate number of repeats for each scenario. To help allocate measurement resources in such data collections for RIID algorithm testing, we consider using only a few real repeats per scenario. In order to reduce uncertainty in the estimated RIID algorithm performance for each scenario, the potential merit of augmenting these real repeats with realistic synthetic repeats is also considered. Our results suggest that for the scenarios and algorithms considered, approximately 10 real repeats augmented with simulated repeats will result in an estimate having comparable uncertainty to the estimate based on using 60 real repeats.

Burr, Tom L [Los Alamos National Laboratory; Hamada, Michael [Los Alamos National Laboratory; Graves, Todd [Los Alamos National Laboratory; Myers, Steve [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

437

Elbow mass flow meter  

DOE Patents [OSTI]

Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

1994-01-01T23:59:59.000Z

438

Beta-decay properties of Zr and Mo neutron-rich isotopes  

E-Print Network [OSTI]

Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the description of beta-decay properties in this mass region.

P. Sarriguren; J. Pereira

2010-06-08T23:59:59.000Z

439

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

DOE Patents [OSTI]

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

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

1982-08-10T23:59:59.000Z

440

Magnesium isotopic systematics of chondrules and CAIs from Allende, Murchison, Murray and Bjurbole. F.-, M. Wadhwa1,  

E-Print Network [OSTI]

Magnesium isotopic systematics of chondrules and CAIs from Allende, Murchison, Murray and Bjurbole: Magnesium isotopic analyses were performed at the Isotope Geochemistry Labora- tory of the Field Museum

Grossman, Lawrence

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Low-energy Coulomb excitation of neutron-rich zinc isotopes  

SciTech Connect (OSTI)

At the radioactive ion beam facility REX-ISOLDE, neutron-rich zinc isotopes were investigated using low-energy Coulomb excitation. These experiments have resulted in B(E2,2{sub 1}{sup +}{yields}0{sub 1}{sup +}) values in {sup 74-80}Zn, B(E2,4{sub 1}{sup +}{yields}2{sub 1}{sup +}) values in {sup 74,76}Zn and the determination of the energy of the first excited 2{sub 1}{sup +} states in {sup 78,80}Zn. The zinc isotopes were produced by high-energy proton- (A=74,76,80) and neutron- (A=78) induced fission of {sup 238}U, combined with selective laser ionization and mass separation. The isobaric beam was postaccelerated by the REX linear accelerator and Coulomb excitation was induced on a thin secondary target, which was surrounded by the MINIBALL germanium detector array. In this work, it is shown how the selective laser ionization can be used to deal with the considerable isobaric beam contamination and how a reliable normalization of the experiment can be achieved. The results for zinc isotopes and the N=50 isotones are compared to collective model predictions and state-of-the-art large-scale shell-model calculations, including a recent empirical residual interaction constructed to describe the present experimental data up to 2004 in this region of the nuclear chart.

Walle, J. van de [Instituut voor Kern-en Stralingsfysica, K. U. Leuven, Leuven (Belgium); ISOLDE, CERN, Geneva (Switzerland); Aksouh, F. [Instituut voor Kern-en Stralingsfysica, K. U. Leuven, Leuven (Belgium); CEA Saclay, DAPNIA/SPhN, Gif-sur-Yvette (France); Behrens, T.; Gernhauser, R.; Kroell, T.; Kruecken, R. [Physik Department E12, Technische Universitaet Muenchen, Garching (Germany); Bildstein, V. [Physik Department E12, Technische Universitaet Muenchen, Garching (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Blazhev, A.; Eberth, J.; Jolie, J.; Reiter, P.; Warr, N.; Weisshaar, D. [Institut fuer Kernphysik, Universitaet Koeln, Koeln (Germany); Cederkaell, J.; Delahaye, P.; Fedosseev, V. N.; Franchoo, S.; Marsh, B. A.; Sieber, T.; Voulot, D. [ISOLDE, CERN, Geneva (Switzerland)] (and others)

2009-01-15T23:59:59.000Z

442

RFNC-VNIIEF Capabilities to Production High Pure Isotopes for Scientific and Medical Applications  

SciTech Connect (OSTI)

In the technical paper there is presented the information on the basic equipment and more than thirty-year experience of RFNC-VNIIEF activities in the sphere of producing highly enriched isotopes of actinide elements--thorium, uranium, neptunium, plutonium, americium and curium--for scientific researches and practical applications. Electromagnetic separator and radiochemical methods provide obtaining of superpure isotope samples for nuclear-physical radiometric and mass-spectrometric equipment, and also as tracers when analyzing environmental contamination. There are presented the structure of the laboratory occupied with these isotopes electromagnetic separation as well as the nomenclature and characteristics of the specimens supplied. There are stated science and engineering elaborations of technologies aimed at producing alpha-ray radiating radionuclides--thorium-229, thorium-228, actinium-225, radium-224--for the purpose of anti-cancer therapy using bismuth-212 and bismuth-213 produced by the specially developed generators. There are presented the basic directions of cooperation with other Russian Institutes in developing this promising line of conversion.

Vesnovskii, S. P.

2002-02-26T23:59:59.000Z

443

Isotopic Analysis- Fluid At Sierra Valley Geothermal Area (1990) | Open  

Open Energy Info (EERE)

Isotopic Analysis- Fluid At Sierra Valley Geothermal Area (1990) Isotopic Analysis- Fluid At Sierra Valley Geothermal Area (1990) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Sierra Valley Geothermal Area (1990) Exploration Activity Details Location Sierra Valley Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1990 Usefulness not indicated DOE-funding Unknown Exploration Basis Determine the recharge of the area Notes Hydrogen and oxygen isotope data on waters of Coso thermal and nonthermal waters were studied. Hydrogen and oxygen isotopes do not uniquely define the recharge area for the Coso geothermal system but strongly suggest Sierran recharge with perhaps some local recharge. References Whelan, J. A. (1 September 1990) Water geochemistry study of

444

Isotopic Analysis- Fluid At Indian Valley Hot Springs Geothermal Area  

Open Energy Info (EERE)

Isotopic Analysis- Fluid At Indian Valley Hot Springs Geothermal Area Isotopic Analysis- Fluid At Indian Valley Hot Springs Geothermal Area (1990) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Indian Valley Hot Springs Geothermal Area (1990) Exploration Activity Details Location Indian Valley Hot Springs Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1990 Usefulness not indicated DOE-funding Unknown Exploration Basis Determine the recharge of the area Notes Hydrogen and oxygen isotope data on waters of Coso thermal and nonthermal waters were studied. Hydrogen and oxygen isotopes do not uniquely define the recharge area for the Coso geothermal system but strongly suggest Sierran recharge with perhaps some local recharge. References

445

CRAD, Management- Oak Ridge National Laboratory High Flux Isotope Reactor |  

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

Management- Oak Ridge National Laboratory High Flux Isotope Management- Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Management- Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 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. CRADs provide a recommended approach and the types of information to gather to assess elements of a DOE contractor's programs. CRAD, Management- Oak Ridge National Laboratory High Flux Isotope Reactor More Documents & Publications CRAD, Nuclear Safety - Oak Ridge National Laboratory High Flux Isotope

446

CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor  

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

Engineering - Oak Ridge National Laboratory High Flux Isotope Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 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. CRADs provide a recommended approach and the types of information to gather to assess elements of a DOE contractor's programs. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor More Documents & Publications CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor

447

Isotope Development & Production for Research and Applications (IDPRA) |  

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

Research » Isotope Research » Isotope Development & Production for Research and Applications (IDPRA) Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Research Isotope Development & Production for Research and Applications (IDPRA) Print Text Size: A A A RSS Feeds FeedbackShare Page 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

448

Isotope Geochemistry Of Minerals And Fluids From Newberry Volcano, Oregon |  

Open Energy Info (EERE)

Isotope Geochemistry Of Minerals And Fluids From Newberry Volcano, Oregon Isotope Geochemistry Of Minerals And Fluids From Newberry Volcano, Oregon Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Isotope Geochemistry Of Minerals And Fluids From Newberry Volcano, Oregon Details Activities (2) Areas (1) Regions (0) Abstract: Isotopic compositions were determined for hydrothermal quartz, calcite, and siderite from core samples of the Newberry 2 drill hole, Oregon. The Δ15O values for these minerals decrease with increasing temperatures. The values indicate that these hydrothermal minerals precipitated in isotopic equilibrium with water currently present in the reservoirs. The Δ18O values of quartz and calcite from the andesite and basalt flows (700-932 m) have isotopic values which require that the equilibrated water Δ18O values increase slightly (- 11.3 to -9.2‰) with

449

Isotopic Analysis- Fluid At Rose Valley Geothermal Area (1990) | Open  

Open Energy Info (EERE)

Isotopic Analysis- Fluid At Rose Valley Geothermal Area (1990) Isotopic Analysis- Fluid At Rose Valley Geothermal Area (1990) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Rose Valley Geothermal Area (1990) Exploration Activity Details Location Rose Valley Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1990 Usefulness not indicated DOE-funding Unknown Exploration Basis Determine the recharge of the area Notes Hydrogen and oxygen isotope data on waters of Coso thermal and nonthermal waters were studied. Hydrogen and oxygen isotopes do not uniquely define the recharge area for the Coso geothermal system but strongly suggest Sierran recharge with perhaps some local recharge. References Whelan, J. A. (1 September 1990) Water geochemistry study of

450

Observations of nitrogen isotope fractionation in deeply embedded protostars  

E-Print Network [OSTI]

(Abridged) The terrestrial planets, comets, and meteorites are significantly enriched in 15N compared to the Sun and Jupiter. While the solar and jovian nitrogen isotope ratio is believed to represent the composition of the protosolar nebula, a still unidentified process has caused 15N-enrichment in the solids. Several mechanisms have been proposed to explain the variations, including chemical fractionation. However, observational results that constrain the fractionation models are scarce. While there is evidence of 15N-enrichment in prestellar cores, it is unclear how the signature evolves into the protostellar phases. Our aim is to measure the 14N/15N ratio around three nearby, embedded low-to-intermediate-mass protostars. Isotopologues of HCN and HNC were used to probe the 14N/15N ratio. A selection of H13CN, HC15N, HN13C, and H15NC transitions was observed with the APEX telescope. The 14N/15N ratios were derived from the integrated intensities assuming a standard 12C/13C ratio. The assumption of optically...

Wampfler, S F; Bizzarro, M; Bisschop, S E

2014-01-01T23:59:59.000Z

451

Vibrational dynamics in isotopically substituted vitreous GeO2  

Science Journals Connector (OSTI)

We report the polarized Raman spectra of vitreous Ge O216, Ge O218, Ge70O2, and Ge74O2. This yields the O16?O18 and Ge70?Ge74 isotopic shifts for nearly all vibrational modes of the pure glassy material. The shifts of the broad high-frequency (infrared-active) modes are as predicted by a nearest-neighbor central-force ideal continuous—random-network model. The shift of the broad dominant Raman line indicates a small but significant dependence on the Ge mass, and this suggests an effect of disorder not included in the central-force theory. The narrow "defect" line at 530 cm-1 appears to be all oxygen motion, and is tentatively identified with a regular ring of bonds. The narrow line at 345 cm-1 is unique in that it exhibits very little oxygen shift; it seems to consist largely of Ge motion, for which we have no firm explanation.

F. L. Galeener; A. E. Geissberger; G. W. Ogar; Jr.; R. E. Loehman

1983-10-15T23:59:59.000Z

452

Neutron scattering length of lithium and boron and their isotopes  

Science Journals Connector (OSTI)

Coherent neutron scattering lengths and free cross sections were measured in order to determine the spin dependent scattering lengths of the isotopes of Li and B.

L. Koester; K. Knopf; W. Waschkowski

1983-01-01T23:59:59.000Z

453

Neutron capture cross sections for neutron-rich isotopes  

Science Journals Connector (OSTI)

Average continuum (Hauser-Feshbach) and resonance (Breit-Wigner) neutron capture rates for neutron-rich isotopes, determined on the basis of...

B. Leist; W. Ziegert; M. Wiescher…

1985-01-01T23:59:59.000Z

454

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

Open Energy Info (EERE)

samples analyzed during this investigation were analyzed for their hydrogen and oxygen isotope contents as a part of previous studies (Goff & Grigsby, 1982; Vuataz & Goff, 1986)....

455

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

Open Energy Info (EERE)

samples analyzed during this investigation were analyzed for their hydrogen and oxygen isotope contents as a part of previous studies (Goff & Grigsby, 1982; Vuataz & Goff, 1986)....

456

Isotopic Analysis At Northern Basin & Range Region (Kennedy ...  

Open Energy Info (EERE)

useful regional reconnaissance DOE-funding Unknown Notes The correspondence of helium isotope ratios and active transtensional deformation indicates a deformation-enhanced...

457

Geothermal reservoir temperatures estimated from the oxygen isotope...  

Open Energy Info (EERE)

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

458

Isotopic Analysis At Nw Basin & Range Region (Kennedy & Van Soest...  

Open Energy Info (EERE)

useful regional reconnaissance DOE-funding Unknown Notes The correspondence of helium isotope ratios and active transtensional deformation indicates a deformation-enhanced...

459

Peel, Kate, Dominik Weiss, and Laura Sigg. Zinc isotope ...  

Science Journals Connector (OSTI)

Zinc isotope composition of settling particles as a proxy for biogeochemical processes in lakes: Insights from the eutrophic Lake Greifen, Switzerland. Kate Peel ...

2009-07-03T23:59:59.000Z

460

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

Open Energy Info (EERE)

samples analyzed during this investigation were analyzed for their hydrogen and oxygen isotope contents as a part of previous studies (Goff & Grigsby, 1982; Vuataz & Goff, 1986)....

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Isotopic Analysis At Walker-Lane Transitional Zone Region (Kennedy...  

Open Energy Info (EERE)

useful regional reconnaissance DOE-funding Unknown Notes The correspondence of helium isotope ratios and active transtensional deformation indicates a deformation-enhanced...

462

Isotopic Analysis- Fluid At Roosevelt Hot Springs Geothermal...  

Open Energy Info (EERE)

and literature review of the Roosevelt Hot Springs Geothermal Area. Notes Stable isotope analysis of thermal fluids determined meteoric origin primarily from the Mineral...

463

Lead and strontium isotopic evidence for crustal interaction...  

Open Energy Info (EERE)

strontium isotopic evidence for crustal interaction and compositional zonation in the source regions of Pleistocene basaltic and rhyolitic magmas of the Coso volcanic field,...

464

Isotopic Analysis At Jemez Springs Area (Goff, Et Al., 1981)...  

Open Energy Info (EERE)

Goff, Et Al., 1981) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis At Jemez Springs Area (Goff, Et Al., 1981) Exploration...

465

Isotopic Analysis At Jemez Springs Area (Rao, Et Al., 1996) ...  

Open Energy Info (EERE)

Rao, Et Al., 1996) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis At Jemez Springs Area (Rao, Et Al., 1996) Exploration...

466

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

Open Energy Info (EERE)

White, Et Al., 1992) Exploration Activity Details Location Valles Caldera - Redondo Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date - 1992 Usefulness...

467

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

Open Energy Info (EERE)

Activity: Isotopic Analysis- Fluid At Valles Caldera - Sulphur Springs Geothermal Area (White, Et Al., 1992) Exploration Activity Details Location Valles Caldera - Sulphur Springs...

468

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

Open Energy Info (EERE)

White, 1986) Exploration Activity Details Location Valles Caldera - Redondo Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date - 1986 Usefulness not...

469

Integrated Approach to Use Natural Chemical and Isotopic Tracers...  

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

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

470

Integrated Approach to Use Natural Chemical and Isotopic Tracers...  

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

Approach to Use Natural Chemical and Isotopic Tracers to Estimate Fracture Spacing and Surface Area in EGS Systems B. Mack Kennedy (Presenter) and H. H. Liu Lawrence Berkeley...

471

Hydrogen Isotope Separation From Noble Gasses in Plasma Exhausts...  

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

Hydrogen Isotope Separation From Noble Gasses in Plasma Exhausts and Other Gas Streams --- Inventors Thomas A. Kozub, William R. Blanchard and Charles A. Gentile The objective of...

472

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

Open Energy Info (EERE)

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

473

Isotopic Analysis At Mt St Helens Area (Shevenell & Goff, 1995...  

Open Energy Info (EERE)

Fraser Goff (1995) Evolution Of Hydrothermal Waters At Mount St Helens, Washington, Usa Additional References Retrieved from "http:en.openei.orgwindex.php?titleIsotopicA...

474

Transcendental L2 -Betti numbers  

E-Print Network [OSTI]

Transcendental L2 -Betti numbers Atiyah's question Thomas Schick G¨ottingen OA Chennai 2010 Thomas Schick (G¨ottingen) Transcendental L2 -Betti numbers Atiyah's question OA Chennai 2010 1 / 24 #12 = ~M/) with fundamental domain F. L2-Betti numbers:= normalized dimension( space of L2-harmonic forms

Sunder, V S

475

Data Compression with Prime Numbers  

E-Print Network [OSTI]

A compression algorithm is presented that uses the set of prime numbers. Sequences of numbers are correlated with the prime numbers, and labeled with the integers. The algorithm can be iterated on data sets, generating factors of doubles on the compression.

Gordon Chalmers

2005-11-16T23:59:59.000Z

476

USING CUMULATIVE NUMBER DENSITIES TO COMPARE GALAXIES ACROSS COSMIC TIME  

SciTech Connect (OSTI)

Comparing galaxies across redshifts at fixed cumulative number density is a popular way to estimate the evolution of specific galaxy populations. This method ignores scatter in mass accretion histories and galaxy-galaxy mergers, which can lead to errors when comparing galaxies over large redshift ranges (?z > 1). We use abundance matching in the ?CDM paradigm to estimate the median change in cumulative number density with redshift and provide a simple fit (+0.16 dex per unit ?z) for progenitors of z = 0 galaxies. We find that galaxy descendants do not evolve in the same way as galaxy progenitors, largely due to scatter in mass accretion histories. We also provide estimates for the 1? range of cumulative number densities corresponding to galaxy progenitors and descendants. Finally, we discuss some limits on cumulative number density comparisons, which arise due to difficulties measuring physical quantities (e.g., stellar mass) consistently across redshifts. A public tool to calculate cumulative number density evolution for galaxies, as well as approximate halo masses, is available online.

Behroozi, Peter S.; Wechsler, Risa H. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford, CA 94305 (United States)] [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford, CA 94305 (United States); Marchesini, Danilo [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States)] [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Muzzin, Adam [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)] [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Papovich, Casey [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States)] [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Stefanon, Mauro [Physics and Astronomy Department, University of Missouri, Columbia, MO 65211 (United States)] [Physics and Astronomy Department, University of Missouri, Columbia, MO 65211 (United States)

2013-11-01T23:59:59.000Z

477

Validation of a Monte Carlo based depletion methodology via High Flux Isotope Reactor HEU post-irradiation examination measurements  

SciTech Connect (OSTI)

The purpose of this study is to validate a Monte Carlo based depletion methodology by comparing calculated post-irradiation uranium isotopic compositions in the fuel elements of the High Flux Isotope Reactor (HFIR) core to values measured using uranium mass-spectrographic analysis. Three fuel plates were analyzed: two from the outer fuel element (OFE) and one from the inner fuel element (IFE). Fuel plates O-111-8, O-350-1, and I-417-24 from outer fuel elements 5-O and 21-O and inner fuel element 49-I, respectively, were selected for examination. Fuel elements 5-O, 21-O, and 49-1 were loaded into HFIR during cycles 4, 16, and 35, respectively (mid to late 1960s). Approximately one year after each of these elements were irradiated, they were transferred to the High Radiation Level Examination Laboratory (HRLEL) where samples from these fuel plates were sectioned and examined via uranium mass-spectrographic analysis. The isotopic composition of each of the samples was used to determine the atomic percent of the uranium isotopes. A Monte Carlo based depletion computer program, ALEPH, which couples the MCNP and ORIGEN codes, was utilized to calculate the nuclide inventory at the end-of-cycle (EOC). A current ALEPH/MCNP input for HFIR fuel cycle 400 was modified to replicate cycles 4, 16, and 35. The control element withdrawal curves and flux trap loadings were revised, as well as the radial zone boundaries and nuclide concentrations in the MCNP model. The calculated EOC uranium isotopic compositions for the analyzed plates were found to be in good agreement with measurements, which reveals that ALEPH/MCNP can accurately calculate burn-up dependent uranium isotopic concentrations for the HFIR core. The spatial power distribution in HFIR changes significantly as irradiation time increases due to control element movement. Accurate calculation of the end-of-life uranium isotopic inventory is a good indicator that the power distribution variation as a function of space and time is accurately calculated, i.e. an integral check. Hence, the time dependent heat generation source terms needed for reactor core thermal hydraulic analysis, if derived from this methodology, have been shown to be accurate for highly enriched uranium (HEU) fuel.

Chandler, David [ORNL; Maldonado, G Ivan [ORNL; Primm, Trent [ORNL

2010-01-01T23:59:59.000Z

478

E-Print Network 3.0 - arc magmatism isotopic Sample Search Results  

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

& Nakamura (1993) Nature 370 e.g. Izu arc: Ishikawa & Nakamura (1993) Nature 370 Boron isotopes help... --Th isotopes in arc magmasTh isotopes in arc magmas For equilibrium:...

479

Mobility determination of lead isotopes in glass for retrospective radon measurements  

Science Journals Connector (OSTI)

......al. Retention of Pb isotopes in glass surfaces for...Vierinen K. The ion guide isotope separator online...Whitlow H. J. Boron diffusion in bulk cobalt...srim.org . Mobility determination of lead isotopes in glass for retrospective......

Mikko Laitinen; Iiro Riihimäki; Jörgen Ekman; A. R. Ananda Sagari; Lennart B. Karlsson; Somjai Sangyuenyongpipat; Sergey Gorelick; Heikki Kettunen; Heikki Penttilä; Ragnar Hellborg; Timo Sajavaara; Johan Helgesson; Harry J. Whitlow

2008-08-01T23:59:59.000Z

480

E-Print Network 3.0 - atomic lines isotope Sample Search Results  

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

lines isotope Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic lines isotope Page: << < 1 2 3 4 5 > >> 1 Isotope selectivity in laser cooling...

Note: This page contains sample records for the topic "isotopes mass number" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

The effect of a micro bubble dispersed gas phase on hydrogen isotope transport in liquid metals under nuclear irradiation  

E-Print Network [OSTI]

The present work intend to be a first step towards the understanding and quantification of the hydrogen isotope complex phenomena in liquid metals for nuclear technology. Liquid metals under nuclear irradiation in,e.g., breeding blankets of a nuclear fusion reactor would generate tritium which is to be extracted and recirculated as fuel. At the same time that tritium is bred, helium is also generated and may precipitate in the form of nano bubbles. Other liquid metal systems of a nuclear reactor involve hydrogen isotope absorption processes, e.g., tritium extraction system. Hence, hydrogen isotope absorption into gas bubbles modelling and control may have a capital importance regarding design, operation and safety. Here general models for hydrogen isotopes transport in liquid metal and absorption into gas phase, that do not depend on the mass transfer limiting regime, are exposed and implemented in OpenFOAMR CFD tool for 0D to 3D simulations. Results for a 0D case show the impact of a He dispersed phase of na...

Fradera, Jorge

2013-01-01T23:59:59.000Z

482

Apparatus for isotopic alteration of mercury vapor  

DOE Patents [OSTI]

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.

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

1988-01-01T23:59:59.000Z

483

Comparison of isotopic transmutation modelling codes  

E-Print Network [OSTI]

. STAMATELATOS, "Fission Product Data for Thermal Reactors Part 2: Users Manual for EPRI-CINDER Code and Data, " LA-6746-MS, Los Alamos National Laboratory (Dec. 1976). 5. H. BATEMAN, ~RGE~di gH gf ~t gym~id 6. M. J. BEIL, "ORIGEN ? The ORNL Isotope... Generation and Depletion Code, " ORNL-4628, Oak Ridge National Laboratory (May, 1973). 7. O. W. HERMANN and R. M. WESTFALL, "ORIGEN-S Scale System Module to Calculate Fuel Depletion, Actinide Transmutation, Fission Product. Buildup and Decay...

Beard, Carl Allen

1990-01-01T23:59:59.000Z

484

Nuclear Data Evaluations for Americium Isotopes  

SciTech Connect (OSTI)

Recent upgrades of 241Am, 242mAm, and 240Am nuclear data in the keV - 30-MeV range are described. The new evaluation takes advantage of recent measurements and advances in calculational modeling methods. The model calculations are especially important for the nuclear data of americium isotopes, because few measurements are available. The nuclear-model code GNASH is extensively used for our evaluations. The new evaluations are given for total, fission, capture (n, 2n), and (n, 3n) reaction cross sections, and vp for 241Am and 242mAm. A new evaluation for 240Am is also given by expanding our modeling feasibility.

Kawano, T.; Talou, P.; Chadwick, M.B.; MacFarlane, R.E.; Young, P.G. [T-16 Nuclear Physics, Los Alamos National Laboratory (United States)

2005-05-24T23:59:59.000Z

485

EMSL - Mass Spectrometer  

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

mass-spectrometer en Physical Properties of Ambient and Laboratory-Generated Secondary Organic Aerosol. http:www.emsl.pnl.govemslwebpublicationsphysical-properties-ambient-and...

486

A nuclear physics program at the Rare Isotope Beams Accelerator Facility in Korea  

SciTech Connect (OSTI)

This paper outlines the new physics possibilities that fall within the field of nuclear structure and astrophysics based on experiments with radioactive ion beams at the future Rare Isotope Beams Accelerator facility in Korea. This ambitious multi-beam facility has both an Isotope Separation On Line (ISOL) and fragmentation capability to produce rare isotopes beams (RIBs) and will be capable of producing and accelerating beams of wide range mass of nuclides with energies of a few to hundreds MeV per nucleon. The large dynamic range of reaccelerated RIBs will allow the optimization in each nuclear reaction case with respect to cross section and channel opening. The low energy RIBs around Coulomb barrier offer nuclear reactions such as elastic resonance scatterings, one or two particle transfers, Coulomb multiple-excitations, fusion-evaporations, and direct capture reactions for the study of the very neutron-rich and proton-rich nuclides. In contrast, the high energy RIBs produced by in-flight fragmentation with reaccelerated ions from the ISOL enable to explore the study of neutron drip lines in intermediate mass regions. The proposed studies aim at investigating the exotic nuclei near and beyond the nucleon drip lines, and to explore how nuclear many-body systems change in such extreme regions by addressing the following topics: the evolution of shell structure in areas of extreme proton to neutron imbalance; the study of the weak interaction in exotic decay schemes such as beta-delayed two-neutron or two-proton emission; the change of isospin symmetry in isobaric mirror nuclei at the drip lines; two protons or two neutrons radioactivity beyond the drip lines; the role of the continuum states including resonant states above the particle-decay threshold in exotic nuclei; and the effects of nuclear reaction rates triggered by the unbound proton-rich nuclei on nuclear astrophysical processes.

Moon, Chang-Bum, E-mail: cbmoon@hoseo.edu [Hoseo University, Asan, Chung-Nam 336-795 (Korea, Republic of)] [Hoseo University, Asan, Chung-Nam 336-795 (Korea, Republic of)

2014-04-15T23:59:59.000Z

487

Stable isotope geochemistry of coal bed and shale gas and related production waters: A review  

Science Journals Connector (OSTI)

Abstract Coal bed and shale gas can be of thermogenic, microbial or of mixed origin with the distinction made primarily on the basis of the molecular and stable isotope compositions of the gases and production waters. Methane, ethane, carbon dioxide and nitrogen are the main constituents of coal bed and shale gases, with a general lack of C2+ hydrocarbon species in gases produced from shallow levels and more mature coals and shales. Evidence for the presence of microbial gas include ?13C–CH4 values less than ? 50‰, covariation of the isotope compositions of gases and production water, carbon and hydrogen isotope fractionations consistent with microbial processes, and positive ?13C values of dissolved inorganic carbon in production waters. The CO2-reduction pathway is distinguished from acetate/methyl-type fermentation by somewhat lower ?13C–CH4 and higher ?D–CH4, but can also have overlapping values depending on the openness of the microbial system and the extent of substrate depletion. Crossplots of ?13C–CH4 versus ?13C–CO2 and ?D–CH4 versus ?13C–H2O may provide a better indication of the origin of the gases and the dominant metabolic pathway than the absolute carbon and hydrogen isotope compositions of methane. In the majority of cases, microbial coal bed and shale gases have carbon and hydrogen isotope fractionations close to those expected for CO2 reduction. Primary thermogenic gases have ?13C–CH4 values greater than ? 50‰, and ?13C values that systematically increase from C1 to C4 and define a relatively straight line when plotted against reciprocal carbon number. Although coals and disseminated organic matter in shales represent a continuum as hydrocarbon source rocks, current data suggest a divergence between these two rock types at the high maturity end. In deep basin shale gas, reversals or rollovers in molecular and isotopic compositions are increasingly reported in what is effectively a closed shale system as opposed to the relative openness in coal measure environments. Detailed geochemical studies of coal bed and shale gas and related production waters are essential to determine not only gas origins but also the dominant methanogenic pathway in the case of microbial gases.

Suzanne D. Golding; Chris J. Boreham; Joan S. Esterle

2013-01-01T23:59:59.000Z

488

Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays  

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 Print Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Print The geometric structure of liquid water has been investigated in detail by many techniques, but many details are still under debate, such as the actual number of hydrogen bonds (at a given time) between the various water molecules. Even less is known about the electronic structure. Since it is the intermittent bonding between water molecules that gives liquid water its peculiar characteristics, the electronic structure plays a crucial role in understanding the properties of the liquid state. Consequently, information essential for insight into chemical and biological processes in aqueous environments is lacking. To address this need, researchers from Germany and the U.S. have used soft x-ray spectroscopy at the ALS to gain detailed insight into the electronic structure of liquid water. Their spectra show a strong isotope and a weak temperature effect, and, for the first time, a splitting of the primary emission line in x-ray emission spectra. By making use of the internal "femtosecond clock" of the core-hole lifetime, a detailed picture of the electronic structure can be painted that involves fast dissociation processes of the probed water molecules.

489

Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays  

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 Print Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Print The geometric structure of liquid water has been investigated in detail by many techniques, but many details are still under debate, such as the actual number of hydrogen bonds (at a given time) between the various water molecules. Even less is known about the electronic structure. Since it is the intermittent bonding between water molecules that gives liquid water its peculiar characteristics, the electronic structure plays a crucial role in understanding the properties of the liquid state. Consequently, information essential for insight into chemical and biological processes in aqueous environments is lacking. To address this need, researchers from Germany and the U.S. have used soft x-ray spectroscopy at the ALS to gain detailed insight into the electronic structure of liquid water. Their spectra show a strong isotope and a weak temperature effect, and, for the first time, a splitting of the primary emission line in x-ray emission spectra. By making use of the internal "femtosecond clock" of the core-hole lifetime, a detailed picture of the electronic structure can be painted that involves fast dissociation processes of the probed water molecules.