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1

Production of Lithium, Beryllium, and Boron by Hypernovae and the Possible Hypernova-Gamma-Ray Burst Connection  

Microsoft Academic Search

We investigate a possible nucleosynthetic signature of highly energetic explosions of C-O cores (``hypernovae'' [HNe]) that might be associated with gamma-ray bursts (GRBs). We note that the direct impact of C- and O-enriched hypernova ejecta on the ambient hydrogen and helium leads to spallation reactions that can produce large amounts of the light nuclides lithium, beryllium, and boron (LiBeB). Using

Brian D. Fields; Frdric Daigne; Michel Cass; Elisabeth Vangioni-Flam

2002-01-01

2

Production of Lithium, Beryllium and Boron and Analysis of Nuclear Gamma-Ray Line Emission in Active Star Forming Regions  

NASA Astrophysics Data System (ADS)

A model for the formation of the elements Lithium, Beryllium and Boron is presented. The main formation mechanism for these elements has been known to be a process called nuclear spallation. Spallation between protons or alpha particles and the Carbon, Nitrogen and Oxygen nuclei result in the production of the isotopes of Li, Be and B. The originally proposed site for spallation, well-mixed interstellar medium, was found to be inconsistent with the recent observations of linearly varying abundances of Be and B with respect to the metallicity in metal-poor stars. We propose a model for spallation occuring in the unmixed ejecta of supernova as the primary mode of production of the isotopes of Li, Be and B. This scenario was simulated by writing a Monte-Carlo code. The results in terms of the energy required for spallation are feasible compared to the total energy released in a supernova explosion. The calculated isotopic ratios produced were found to generally agree with the observed values. Recent observations of Orion region showing excess flux in 3-7 MeV range, identified as Carbon and Oxygen nuclear deexcitation lines, were followed by models proposing spallation in the vicinity of supernova by collision between energetic C), O nuclei and protons or alpha particles in the surrounding ambient medium. We searched for similar emission from other nearby OB associations, the Cygnus region. Cygnus region contains several large OB associations, including Wolf-Rayet stars, and has a total wind power almost 100 times larger than that in the Orion complex. We present the results from our study of the gamma-ray emission in the 0.75-30 MeV range from the Cygnus region using data from the COMPTEL instrument onboard the Compton Gamma-Ray Observatory (CGRO). In the 3-7 MeV band, where Orion emission is most prominent, we do not find significant emission. We do find significant emission at 1.8 MeV, resulting from the radioactive decay of 26Al. This flux is consistent with the amount predicted from known sources of 26Al in this region.

Majmudar, Deepa Paresh

3

Beryllium and boron in metal-poor stars  

Microsoft Academic Search

Knowledge of lithium, beryllium, and boron abundances in stars of the Galactic halo and disk plays a major role in our understanding of Big Bang nucleosynthesis, cosmic-ray physics, and stellar interiors. 9Be and 10B are believed to originate entirely from spallation reactions in the interstellar medium (ISM) between alpha-particles and protons and heavy nuclei like carbon, nitrogen, and oxygen (CNO),

Francesca Primas

2010-01-01

4

Beryllium and boron in metal-poor stars  

NASA Astrophysics Data System (ADS)

Knowledge of lithium, beryllium, and boron abundances in stars of the Galactic halo and disk plays a major role in our understanding of Big Bang nucleosynthesis, cosmic-ray physics, and stellar interiors. 9Be and 10B are believed to originate entirely from spallation reactions in the interstellar medium (ISM) between ?-particles and protons and heavy nuclei like carbon, nitrogen, and oxygen (CNO), whereas 11B may have an extra production channel via neutrino-spallation. Beryllium and boron are both observationally challenging, with their main resonant doublets falling respectively at 313 nm and at 250 nm. The advent of 8-10m class telescopes equipped with highly sensitive (in the near-UV/blue) spectrographs has opened up a new era of Be abundance studies. Here, I will review and discuss the most interesting results of recent observational campaigns in terms of formation and evolution of these two light elements.

Primas, Francesca

2010-04-01

5

Double photoionization of excited lithium and beryllium  

NASA Astrophysics Data System (ADS)

We present total, energy-sharing, and triple differential cross sections for one-photon, double ionization of lithium and beryllium starting from aligned, excited P states. We employ a recently developed hybrid atomic orbital with numerical grid method based on the finite-element discrete-variable representation and exterior complex scaling. Comparisons with calculated results for the ground-state atoms, as well as analogous results for ground-state and excited helium, serve to highlight important selection rules and show some interesting effects that relate to differences between inter- and intrashell electron correlation.

Yip, F. L.; McCurdy, C. W.; Rescigno, T. N.

2010-06-01

6

Measurement of the Isotopic Composition of Cosmic-Ray Helium, Lithium, Beryllium, and Boron up to 1700 MEV per Atomic Mass Unit  

NASA Astrophysics Data System (ADS)

We present data from the second flight of the superconducting magnet instrument for light isotopes (SMILI), which took place on 1991 July 24. This instrument was optimized to determine the isotopic composition of He, Li, Be, and B in the Galactic cosmic rays, up to an energy of 2 GeV amu-1. The abundances of He, Li, and B are found to be consistent with standard models of cosmic-ray propagation. Our measurement of the abundances of the beryllium isotopes suggests an enhancement of the fraction of the isotope 10Be over that found at low energy. Of 26 beryllium events, nine are found to be 10Be. Monte Carlo calculations based on this observation imply the mean lifetime of cosmic rays to be less than 6 Myr at the 97.5% confidence level.

Ahlen, S. P.; Greene, N. R.; Loomba, D.; Mitchell, J. W.; Bower, C. R.; Heinz, R. M.; Mufson, S. L.; Musser, J.; Pitts, J. J.; Spiczak, G. M.; Clem, J.; Guzik, T. G.; Lijowski, M.; Wefel, J. P.; McKee, S.; Nutter, S.; Tomasch, A.; Beatty, J. J.; Ficenec, D. J.; Tobias, S.

2000-05-01

7

Beryllium and Boron abundances in population II stars  

NASA Astrophysics Data System (ADS)

The scientific focus of this program was to undertake UV spectroscopic abundance analyses of extremely metal poor stars with attention to determining abundances of light elements such as beryllium and boron. The abundances are likely to reflect primordial abundances within the early galaxy and help to constrain models for early galactic nucleosynthesis. The general metal abundances of these stars are also important for understanding stellar evolution.

1995-03-01

8

On temperature bifurcation of beryllium and lithium plasma facing components  

SciTech Connect

The mechanism of temperature bifurcation of plasma contacting surfaces due to recycling of the ionized surface material vapor is considered. It is shown that this mechanism can lead to overheating of beryllium and lithium plasma facing components (in particular, in fusion devices) prior to the thermionic electron emission mechanism. The surface temperatures and the plasma parameters, at which the considered mechanism triggers the local overheating of beryllium and lithium components, are evaluated. The increase in the surface heat load due to secondary electron emission is also considered. It is shown that the combined effects of energy and impact angle distributions of the plasma electrons can increase the averaged secondary electron emission yield to values higher than unity and can lower the average electron energy, at which such yields are achieved.

Smirnov, R. D.; Krasheninnikov, S. I.; Pigarov, A. Yu. [University of California San Diego, La Jolla, California 92093 (United States)

2009-12-15

9

Late main-sequence evolution of lithium and beryllium  

NASA Astrophysics Data System (ADS)

We examine the effects of the tachocline diffusion process on the surface abundances of light elements in solar-like stars (M*=0.96-1.04 Msun). Acting during main sequence evolution, the tachocline diffusion can account for the gradual decrease in lithium surface abundance while preserving beryllium, in agreement with the most recent observational data for open cluster stars older than the Hyades ( ~ 600 Myr). We show that helioseismology and observations of surface rotation demand a nearly solid-body rotation of solar analogs after ~1 Gyr. By then, these stars have become slow rotators and lost most of their initial angular momentum. We argue that mixing due to angular momentum loss does not appear to be a viable mechanism to account for the observed abundances. Using the results of helioseismology and of the observations of solar lithium abundance, we calibrate the two parameters of the tachocline mixing, the Brunt-Visl frequency and the tachocline thickness. We then evolve stellar models starting at the Hyades age and compare the results of 7Li and 9Be abundances to the observations of M 67 ( ~ 4.5 Gyr). Finally, we investigate the effects of slight differences in specific metal abundance ratios on the tachocline diffusion. Because of opacity effects, we find differences in the amount of lithium depletion of ~ 0.5 dex for solar effective temperature and iron abundance at the age of M 67 that can partly explain the observed lithium spread in this cluster.

Piau, L.; Randich, S.; Palla, F.

2003-09-01

10

Comparison of beryllium oxide and pyrolytic graphite crucibles for boron doped silicon epitaxy  

SciTech Connect

This article reports on the comparison of beryllium oxide and pyrolytic graphite as crucible liners in a high-temperature effusion cell used for boron doping in silicon grown by molecular beam epitaxy. Secondary ion mass spectroscopy analysis indicates decomposition of the beryllium oxide liner, leading to significant incorporation of beryllium and oxygen in the grown films. The resulting films are of poor crystal quality with rough surfaces and broad x-ray diffraction peaks. Alternatively, the use of pyrolytic graphite crucible liners results in higher quality films.

Ali, Dyan; Richardson, Christopher J. K. [Laboratory for Physical Sciences, University of Maryland, College Park, Maryland 20740 (United States)

2012-11-15

11

Preparation and physical characteristics of a lithium-beryllium-substituted fluorapatite  

SciTech Connect

A lithium-beryllium-substituted fluorapatite, Li{sub 0.50}Be{sub 0.25}Ca{sub 4.50}(PO{sub 4}){sub 3}F, has been prepared by means of a high-temperature reaction between lithium beryllium fluoride, Li{sub 2}BeF{sub 4}, and tricalcium phosphate, Ca{sub 3}(PO{sub 4}){sub 2}. This material has potential application as a waste form for radioactive and toxic fluoride salts. Monitoring of the reaction progress by differential scanning calorimetry indicated that the reaction was initiated by melting of the fluoride salt and that it was fast and complete. While reactive sintering of lithium beryllium fluoride with tricalcium phosphate led to a rather porous product, melting of the reactants with subsequent solidification readily produced a substituted fluorapatite with a near-theoretical bulk density.

Lexa, D. [Argonne National Lab., IL (United States). Chemical Technology Div.

1999-01-01

12

Measurement of the melting point temperature of several lithium-sodium-beryllium fluoride salt (FLINABE) mixtures  

Microsoft Academic Search

The molten salt Flibe, a combination of lithium and beryllium flourides, was studied for molten salt fission reactors and has been proposed as a breeder and coolant for the fusion applications. 2LiF-BeF melts at 460 C. LiF-BeF melts at a lower temperature, 363 C, but is rather viscous and has less lithium breeder. In the Advanced Power Extraction (APEX) Program,

Timothy J. Boyle; Kenneth P. Troncosa; Richard Einar Nygren; Thomas Joseph Lutz; Jimmie M. McDonald; Tina Joan Tanaka; Michael Andrew Ulrickson

2004-01-01

13

Magnetization of beryllium oxide in the presence of nonmagnetic impurities: Boron, carbon, and nitrogen  

NASA Astrophysics Data System (ADS)

The electronic and magnetic states of a nonmagnetic insulator, namely, beryllium oxide, doped with nonmagnetic 2 p elements (boron, carbon, and nitrogen) are studied using the density functional theory. The spin polarization of the 2 p impurity states, as well as the transition of the doped BeO:(B,C,N) systems to the states of semiconducting or half-metallic magnets, is observed. The prospects for creating new magnetic materials by doping nonmagnetic insulators with nonmagnetic p impurities are discussed.

Shein, I. R.; Ryzhkov, M. V.; Gorbunova, M. A.; Makurin, Yu. N.; Ivanovski?, A. L.

2007-05-01

14

Stark shifting of analogous spectral lines along isoelectronic sequences of beryllium and boron  

NASA Astrophysics Data System (ADS)

We report the comparison of experimental and theoretical (semiclassical and semiempirical) Stark shifts of plasma broadened lines belonging to 3s-3p transitions along beryllium and 3s-3p and 3p-3d transitions along boron isoelectronic sequence. The light source was a low pressure pulsed arc. The plasma electron densities were determined from the width of the Hell P? line while the electron temperatures were measured from the relative intensities of spectral lines. .

Blagojevi?, Branimir; Popovi?, Milan V.; Konjevi?, Nikola

2001-04-01

15

Use of a chelate complex with boron as a lithium salt for lithium battery electrolytes  

Microsoft Academic Search

A chelate complex with boron, lithium bis[2,3-naphthalenediolato(2-)-O,O]borate was used in lithium battery electrolytes for Li\\/VO prototype cells. This lithium salt remains a safe and thermally stable compound up to 320 C without melting. A high specific conductivity (4.63 mS\\/cm) is exhibited in spite of its high viscosity (1.732 cP) in a 0.5 mol\\/dm³ electrolyte\\/ethylene carbonate-1,2-dimethoxyethane (mol ratio 2:3) binary solvent

M. Handa; S. Fukuda; Y. Sasaki; K. Usami

1997-01-01

16

Surface tension of molten mixtures of fluorides of lithium, beryllium, and thorium  

SciTech Connect

Melts of mixtures of fluorides of lithium, beryllium, thorium and uranium satisfy most completely the many requirements imposed on fuel composites and breeder-zone materials in a liquid-salt nuclear reactor, and therefore there is a need for information on the physicochemical properties of such melts. This paper reports on a study in which the surface tension of three-component melts containing fluorides of thorium, beryllium and lithium were measured by the maximum-pressure method in a gas bubble. The salts investigated were placed in glass carbon crucibles. The material used for the capillaries was nickel, which is resistant to the action of fluoride melts. As the working gas, the authors used argon from which the traces of moisture and oxygen had been removed. The surface tension was calculated by the Cantor-Schrodinger method and in the investigations close attention was paid to the preparation of the appropriate anhydrous salts.

Klimenkov, A.A.; Chevinskii, Y.F.; Kurbatov, N.N.; Raspopin, S.P.

1984-12-01

17

Production of Lithium, Beryllium and Boron in Supernova Ejecta  

Microsoft Academic Search

We model the nucleosynthesis of light elements (Li,Be,B) by spallation of C,N,O targets by accelerated H,He in expanding supernova ejecta. Recent observations of metal-poor halo dwarfs indicate that these light element abundance increases linearly with metalicity, i.e. the ratio of these elements to iron is constant. The model of formation of these elements in interstellar medium where spallation takes place

Deepa Majmudar

1995-01-01

18

Production of Lithium, Beryllium and Boron in Supernova Ejecta  

NASA Astrophysics Data System (ADS)

We model the nucleosynthesis of light elements (Li,Be,B) by spallation of C,N,O targets by accelerated H,He in expanding supernova ejecta. Recent observations of metal-poor halo dwarfs indicate that these light element abundance increases linearly with metalicity, i.e. the ratio of these elements to iron is constant. The model of formation of these elements in interstellar medium where spallation takes place by galactic cosmic rays colliding with interstellar matter would not give a linear dependence of spallation products with iron abundance. We investigate the scenario of formation of these elements in expanding supernova where spallation would take place in an unmixed medium of supernova ejecta, which would give the observed linear dependence. Calculations will be presented on energetics of this scenario and abundances and ratios of the isotopes of Li,Be,B.

Majmudar, Deepa

1995-12-01

19

Lithium, beryllium, and boron in cosmology and cosmic rays.  

NASA Astrophysics Data System (ADS)

Observations of metal-deficient halo stars indicate the presence of 6Li, Be, and B in the early Galaxy. It is shown that there is neither convincing observational evidence nor theoretical motivation that these elements are primordial. Evidence is presented which suggests that they were produced by cosmic ray interactions in the early interstellar medium. If the 6Li, Be and B are indeed of cosmic ray origin, then the same cosmic ray interactions also produce 7Li. One can deduce this (small) cosmic ray component to Li subtract this from the observed abundance to obtain the true, primordial Li abundance.

Fields, B. D.

20

Thermodynamic Functions of Some Gaseous Diatomic Halides of Aluminum, Boron, and Lithium  

Microsoft Academic Search

A literature survey was made to locate spectroscopic data on the gaseous halides of aluminum, boron, and lithium. The thermodynamic functions were computed and a tabulation of the heat capacity, enthalpy, and entropy of the gaseous diatomic bromides, chlorides, and fluorides of aluminum, boron, and lithium has been made from zero to 6000K in order that this useful thermodynamic information

Robert L. Altman

1959-01-01

21

Possible sources of the Population I lithium abundance and light-element evolution  

Microsoft Academic Search

One-zone numerical models of Galactic chemical evolution of the light elements (lithium, beryllium, boron, and deuterium) with a broad sample of possible stellar lithium production sites and star formation histories, including the multiple merger model of Mathews and Schramm (1992), are examined. Models with high primordial lithium are constrained by observations of lithium and potassium in the interstellar medium of

Lawrence E. Brown

1992-01-01

22

Graphitized boron-doped carbon foams: Performance as anodes in lithium-ion batteries  

Microsoft Academic Search

The electrochemical performance as potential anodes in lithium-ion batteries of several boron-doped and non-doped graphitic foams with different degree of structural order was investigated by galvanostatic cycling. The boron-doped foams were prepared by the co-pyrolysis of a coal and two boron sources (boron oxide and a boranepyridine complex), followed by heat treatment in the 24002800C temperature interval. The extent of

Elena Rodrguez; Ignacio Camen; Roberto Garca; Ana B. Garca

2011-01-01

23

Early-life exposure to lithium and boron from drinking water.  

PubMed

The transfer of lithium and boron from exposed mothers to fetuses and breast-fed infants was investigated in areas in northern Argentina and Chile with up to 700 ?g lithium/L and 5-10 mg boron/L in drinking water. Maternal and cord blood concentrations were strongly correlated and similar in size for both lithium (47 and 70 ?g/L, respectively) and boron (220 and 145 ?g/L, respectively). The first infant urine produced after birth contained the highest concentrations (up to 1700 ?g lithium/L and 14,000 ?g boron/L). Breast-milk contained 40 and 60% of maternal blood concentrations of lithium and boron, respectively (i.e. about 30 and 250 ?g/L, respectively, in high exposure areas), and infant urine concentrations decreased immediately after birth (120 ?g lithium/L and 920 ?g boron/L). We conclude that lithium and boron easily passed the placenta to the fetus, and that exclusively breast-fed infants seemed to have lower exposure than formula-fed infants. PMID:23017911

Harari, Florencia; Ronco, Ana Mara; Concha, Gabriela; Llanos, Miguel; Grandr, Margaretha; Castro, Francisca; Palm, Brita; Nermell, Barbro; Vahter, Marie

2012-09-07

24

The Evolution of Galactic Beryllium and Boron Traced by Magnesium and Calcium  

NASA Astrophysics Data System (ADS)

Beryllium and boron abundances are consistently derived on the parameter scale of two recent uniform stellar Mg and Ca abundance studies, one utilizing non-LTE parameters and abundances, the other assuming LTE. The results are used to explore the BeB-Mg and BeB-Ca relations at low metallicity as urged by B. D. Fields and coworkers. The slopes of all logarithmic BeB-MgCa relations, regardless of light element (Be or B), metallicity tracer (Mg or Ca), or parameter scale (non-LTE or LTE), are found to lie in the range 1.1-1.3. These results using the ?-elements Mg and Ca confirm the need for a metal-poor ``primary'' BeB production mechanism (perhaps in addition to standard Galactic cosmic rays) previously inferred from BeB-Fe and questioned BeB-O relations.

King, Jeremy R.

2002-01-01

25

On the stability of boron nitride with lithium alloy electrodes in molten salt cells  

NASA Astrophysics Data System (ADS)

Experiments were carried out to determine the stability of boron nitride separator material in molten salt cells using lithium chloride-potassium chloride (LiCl-KCl) eutectic electrolyte and two stainless steel screen electrodes. The potentials of these electrodes were set by two separate electrical circuits and a lithium-silicon (Li-Si) reservoir electrode. The boron nitride separator was found stable at potentials above -136 mV with respect to a lithium-aluminum reference electrode at 700 K. The separator reacted with lithium and became conductive at potentials more reducing than about -200 mV. Formation of a boride and Li3N led to the conductivity.

Sharma, R. A.; Bradley, T. G.

1981-09-01

26

On the stability of boron nitride with lithium alloy electrodes in molten salt cells  

Microsoft Academic Search

Experiments were carried out to determine the stability of boron nitride separator material in molten salt cells using lithium chloride-potassium chloride (LiCl-KCl) eutectic electrolyte and two stainless steel screen electrodes. The potentials of these electrodes were set by two separate electrical circuits and a lithium-silicon (Li-Si) reservoir electrode. The boron nitride separator was found stable at potentials above -136 mV

R. A. Sharma; T. G. Bradley

1981-01-01

27

Formation of cBN nanoparticles by helium, lithium and boron ion implantation  

Microsoft Academic Search

Ion induced phase transformation from the soft graphitic hexagonal boron nitride (h-BN) to ultrahard cubic boron nitride (c-BN) nanoparticles is presented in the work herein. Ion implantation was used as a technique to introduce boron lithium and helium ions, at the energy of 150keV and fluences ranging from 11014 to 11016ions\\/cm2, into hot pressed, polycrystalline h-BN. Analyses using Raman Spectroscopy

Emily Aradi; Rudolph M. Erasmus; Trevor E. Derry

28

Method for hot pressing beryllium oxide articles  

DOEpatents

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide - lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Ballard, A.H.; Godfrey, T.G. Jr.; Mowery, E.H.

1986-10-10

29

Measurement of the Melting Point Temperature of Several Lithium-Sodium-Beryllium Fluoride Salt (Flinabe) Mixtures  

SciTech Connect

The molten salt Flibe, a combination of lithium and beryllium fluorides studied for molten salt fission reactors, has been proposed as a breeder and coolant for fusion applications. The melting points of 2LiF-BeF{sub 2} and LiF-BeF{sub 2} are 460 deg. C and 363 deg. C, but LiF-BeF{sub 2} is rather viscous and has less lithium for breeding. In the Advanced Power Extraction (APEX) Program, concepts with a free flowing liquid for the first wall and blanket were investigated. Flinabe (a mixture of LiF, BeF{sub 2} and NaF) was selected for a molten salt design because a melting temperature below 350 deg. C appeared possible and this provided an attractive operating temperature window for a reactor. To confirm that a ternary salt with a low melting temperature existed, several combinations of the fluoride salts, LiF, NaF and BeF{sub 2}, were melted in a stainless steel crucible under vacuum. One had an apparent melting temperature of 305 deg. C. The test system, preparation of the mixtures, melting procedures and temperature curves for the melting and cooling are presented along with the apparent melting points. Thermal modeling of the salt pool and crucible is reported in an accompanying paper.

McDonald, J.M; Nygren, R.E.; Lutz, T.J.; Tanaka, T.J; Ulrickson, M.A.; Boyle, T.J.; Troncosa, K.P. [Sandia National Laboratories (United States)

2005-04-15

30

Endogenous lithium and boron red cell-plasma ratios  

Microsoft Academic Search

This study was undertaken to compare endogenous lithium concentrations in human blood and its components from normal donors\\u000a versus bipolar patients. The patients were not on lithium therapy at the time that the blood samples were donated and had\\u000a not received any lithium therapy for at least 2 yr. Blood components were separated by centrifugation. The analytical method\\u000a for lithium

W. Brian Clarke; Richard Guscott; R. Gregory Downing; Richard M. Lindstrom

2004-01-01

31

11B NMR of boron-doped graphite as the negative electrode of a lithium secondary battery  

Microsoft Academic Search

Boron-doped graphite used as a negative electrode for a lithium rechargeable battery is known to have higher discharge capacity than undoped graphite. Herein, the graphites were mixed with 1, 2.5, 5, and 7 wt.% of boron carbide during the graphitizing process. The structural states of boron in those boron-doped graphites were successfully identified by solid-state 11B NMR spectroscopy. For 1

Youngil Lee; Duk-Young Han; Donghoon Lee; Ae Ja Woo; Sam Hyeon Lee; Daeho Lee; Young Kyu Kim

2002-01-01

32

Large scale boron carbon nitride nanosheets with enhanced lithium storage capabilities.  

PubMed

Few-layered boron carbon nitride nanosheets are synthesized by a simple and environmentally friendly process. The BCN nanosheets have 2-6 atomic layers with high surface area and show enhanced storage performance in lithium batteries, as well as a stable capacity of ~100 mA h g(-1) at 2 A g(-1) for 5000 cycles. PMID:23108161

Lei, Weiwei; Qin, Si; Liu, Dan; Portehault, David; Liu, Zongwen; Chen, Ying

2012-10-29

33

Measurement of the melting point temperature of several lithium-sodium-beryllium fluoride salt (FLINABE) mixtures.  

SciTech Connect

The molten salt Flibe, a combination of lithium and beryllium flourides, was studied for molten salt fission reactors and has been proposed as a breeder and coolant for the fusion applications. 2LiF-BeF{sub 2} melts at 460 C. LiF-BeF{sub 2} melts at a lower temperature, 363 C, but is rather viscous and has less lithium breeder. In the Advanced Power Extraction (APEX) Program, concepts with a free flowing ternary molten salt for the first wall surface and blanket were investigated. The molten salt (FLiNaBe, a ternary mixture of LiF, BeF2 and NaF) salt was selected because a melting temperature below 350 C that would provide an attractive operating temperature window for a reactor application appeared possible. This information came from a Russian binary phase diagram and a US ternary phase diagram in the 1960's that were not wholly consistent. To confirm that a ternary salt with a low melting temperature existed, several combinations of the fluoride salts, LiF, NaF and, BeF{sub 2}, were melted in a small stainless steel crucible under vacuum. The proportions of the three salts were selected to yield conglomerate salts with as low a melting temperature as possible. The temperature of the salts and the crucible were recorded during the melting and subsequent re-solidification using a thermocouple directly in the salt pool and two thermocouples embedded in the crucible. One mixture had an apparent melting temperature of 305 C. Particular attention was paid to the cooling curve of the salt temperature to observe evidence of any mixed intermediate phases between the fully liquid and fully solid states. The clarity, texture, and thickness were observed and noted as well. The test system, preparation of the mixtures, and the melting procedure are described. The temperature curves for the melting and cooling of each of the mixtures are presented along with the apparent melting points. Thermal modeling of the salt pool and crucible was also done and is reported in a separate paper.

Boyle, Timothy J.; Troncosa, Kenneth P.; Nygren, Richard Einar; Lutz, Thomas Joseph; McDonald, Jimmie M.; Tanaka, Tina Joan; Ulrickson, Michael Andrew

2004-09-01

34

METHOD OF BRAZING BERYLLIUM  

DOEpatents

A process is described for brazing beryllium metal parts by coating the beryllium with silver (65- 75 wt%)-aluminum alloy using a lithium fluoride (50 wt%)-lithium chloride flux, and heating the coated joint to a temperature of about 700 un. Concent 85% C for about 10 minutes. (AEC)

Hanks, G.S.; Keil, R.W.

1963-05-21

35

Formation of c-BN nanoparticles by helium, lithium and boron ion implantation  

NASA Astrophysics Data System (ADS)

Ion induced phase transformation from the soft graphitic hexagonal boron nitride (h-BN) to ultrahard cubic boron nitride (c-BN) nanoparticles is presented in the work herein. Ion implantation was used as a technique to introduce boron lithium and helium ions, at the energy of 150 keV and fluences ranging from 1 1014 to 1 1016 ions/cm2, into hot pressed, polycrystalline h-BN. Analyses using Raman Spectroscopy showed that He+, Li + and B+ led to a h-BN to c-BN phase transition, evident from the longitudinal optical (LO) Raman phonon features occurring in the implanted samples' spectra. The nature of these phonon peaks and their downshifting is explained using the spatial phonon correlation model.

Aradi, Emily; Erasmus, Rudolph M.; Derry, Trevor E.

2012-02-01

36

Electrochemical behaviour of SnO 2 doped with boron and indium in anodes for lithium secondary batteries  

Microsoft Academic Search

Nanoparticles of SnO2 were doped with boron and indium for use as active anode materials in non-aqueous lithium batteries. The cells thus obtained were found to exhibit between 1.0 and 0.0 V their best cycling properties. Undoped SnO2 and particularly low boron-doped samples exhibited the best electrochemical characteristics, as reflected in an increased specific capacity and in improved cycling properties.

Julin Morales; Luis Snchez

1999-01-01

37

Boron, Samarium, Gadolinium, Lithium and Hydrogen Abundances in Antarctic Meteorites  

NASA Astrophysics Data System (ADS)

The boron concentrations in 13 Antarctic meteorite specimens were published in 1988 (1). Here we report B, Sm, Gd, and some H abundances in 27 additional chondrites and 14 achondrites, all measured by prompt gamma neutron activation analysis: some Li analyses were also made, using AAS. The accuracy and precision of analysis are particularly important for B, Sm, and Gd, whose abundance levels in meteorites can be 1 ppm or less, so multiple analyses of Reference Materials DTS-1, PCC-1, BHVO-1, and JG-1 were made for controls. The results showed good agreement with recommended values for B and H (expressed as H2O); the results were good also for Sm and Gd but at concentrations 10x meteorites. Precision was adequate, averaging 10 to 15% (1 s.d.) of amount present. Stringent precautions against contamination were maintained during handling and analysis. Natural mobilisation of B in the Antarctic weathering environment is however known to take place (1). The summarised results are as follows: B Sm Gd H2O Li ppm ppm ppm % ppm Mean of 6 analyses of 3 C.C. 0.93 0.36 0.39 0.94 4.3 Mean of 42 analyses of 37 CH 0.78 0.35 0.30 0.97 5.8 Mean of 7 eucrites, howardites 2.7 1.1 1.9 0.75 - The principal observations are that (a) B and Li abundances in CH and C.C. resemble earlier estimates, (b) Sm and Gd in CH and C.C. are markedly higher than expected, (c) B, Sm, and Gd are significantly higher in eucrites and howardites than in other meteorites (including aubrites, diogenites, and ureilites) and (d) estimates of H2O on individual meteorites agree quite well with published results by conventional methods. These observations form the basis for further interpretations. (1) D. M. Shaw, M. D. Higgins, R. W. Hinton, M. G. Truscott, and T. A. Middleton (1988) Boron in chondritic meteorites. Geochimica et Cosmochimica Acta 52, 2311-2319.

Shaw, D. M.; Smith, P. L. C.; Zhai, M.

1992-07-01

38

Method for hot pressing beryllium oxide articles  

DOEpatents

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Ballard, Ambrose H. (Oak Ridge, TN); Godfrey, Jr., Thomas G. (Oak Ridge, TN); Mowery, Erb H. (Clinton, TN)

1988-01-01

39

The lithium-boron alloy anode in molten nitrate electrolytes  

SciTech Connect

Potentiostatic studies of Li(B) anodes in molten LiNO/sub 3/ at 300/sup 0/C indicate that at 80% peak open-circuit voltage, a broad flat discharge at 780 mA cm/sup -2/ is obtained. Galvanostatic discharge studies show stable anode potentials more negative than -3V (vs. Ag/sup +//Ag) in LiNO/sub 3/ at 300 mA cm/sup -2/ over a temperature range of 270/sup 0/-350/sup 0/C. At temperatures above 350/sup 0/C, deflagrations of the anode were often observed, particularly after deep discharge. Electrolyte composition is a key factor in determining the current density-potential and potential-temperature characteristics of the Li(B) anode in molten nitrates. Experiments in equimolar LiNO/sub 3/-KNO/sub 3/ exhibit open-circuit anode potentials up to 0.2V less electronegative to that seen in equimolar LiNO/sub 3/-NaNO/sub 3/ electrolyte. In a like fashion at 300 mA cm/sup -2/ and 300/sup 0/C, the use of LiNO/sub 3/-KNO/sub 3/ equimolar electrolyte results in Li(B) anode potentials up to 0.45V more positive than those seen in LiNO/sub 3/-NaNO/sub 3/ equilmolar electrolyte and up to 0.85V more positive than that seen in LiNO/sub 3/ electrolyte. Single cell tests integrating the Li(B) anode with existing silver ion cathode technology exhibit stable cell potentials in excess of 3V at 300 mA cm/sup -2/ at 300/sup 0/C. The two phase composition of the Li(B) alloy allows for exceptional anode stability at the high anode potential of elemental lithium.

McManis, G.E.; Fletcher, A.N.; Miles, M.H.

1984-02-01

40

Heats of formation of beryllium, boron, aluminum, and silicon re-examined by means of W4 theory.  

PubMed

Benchmark total atomization energies (TAE0 values) were obtained, by means of our recent W4 theory [Karton, A.; Rabinowitz, E.; Martin, J. M. L.; Ruscic, B. J. Chem. Phys. 2006, 125, 144108], for the molecules Be2, BeF2, BeCl2, BH, BF, BH3, BHF2, B2H6, BF3, AlF, AlF3, AlCl3, SiH4, Si2H6, and SiF4. We were then able to deduce "semi-experimental" heats of formation for the elements beryllium, boron, aluminum, and silicon by combining the calculated TAE0 values with experimental heats of formation obtained from reactions that do not involve the species Be(g), B(g), Al(g), and Si(g). The elemental heats of formation are fundamental thermochemical quantities that are required whenever a molecular heat of formation has to be derived from a calculated binding energy. Our recommended DeltaH degrees f,0 [A(g)] values are Be 76.4+/-0.6 kcal/mol, B 135.1+/-0.2 kcal/mol, Al 80.2+/-0.4 kcal/mol, and Si 107.2+/-0.2 kcal/mol. (The corresponding values at 298.15 K are 77.4, 136.3, 80.8, and 108.2 kcal/mol, respectively.) The Be value is identical to the CODATA recommendation (but with half of the uncertainty), while the B, Al, and Si values represent substantial revisions from established earlier reference data. The revised B and Si values are in agreement with earlier semi-ab initio derivations but carry much smaller uncertainties. PMID:17567115

Karton, Amir; Martin, Jan M L

2007-06-14

41

Structure of Lithium-Boron Alloys and Their Performance as Potential Anodes for High Power Molten Salt Batteries.  

National Technical Information Service (NTIS)

Anodic discharge curves in the LiCl-KCl eutectic melt have been obtained for two lithium-boron alloys (70 and 80 weight % Li) between 673 and 873K (400 and 600 C) and from 2-8 A/sq cm. The behavior of Li contained in wicks of porous Ni was also studied fo...

L. E. DeVries S. D. James

1976-01-01

42

Inhomogeneous big bang nucleosynthesis: Upper limit on ?b and production of lithium, beryllium, and boron  

NASA Astrophysics Data System (ADS)

We examine the big bang nucleosynthesis (BBN) process in the presence of small-scale baryon inhomogeneities. Primordial abundance yields for D, 4He, 6Li, 7Li, 9Be, and 11B are computed for wide ranges of parameters characterizing the inhomogeneities taking account of all relevant diffusive and hydrodynamic processes. These calculations may be of interest due to (a) recent observations of the anisotropies in the cosmic microwave background radiation favoring slightly larger baryonic contribution to the critical density, ?b, than allowed by a standard BBN scenario and (b) new observational determinations of 6Li and 9Be in metal-poor halo stars. We find considerable parameter space in which production of D and 4He is in agreement with observational constraints even for ?bh2 a factor 2 or 3 larger than the ?b inferred from standard BBN. Nevertheless, in this parameter space synthesis of 7Li in excess of the inferred 7Li abundance on the Spite plateau results. Production of 6Li, 9Be, and 11B in inhomogeneous BBN scenarios is still typically well below the abundance of these isotopes observed in the most metal-poor stars to date thus neither confirming nor rejecting inhomogeneous BBN. In an Appendix we summarize results of a reevaluation of baryon diffusion constants entering inhomogeneous BBN calculations.

Jedamzik, Karsten; Rehm, Jan B.

2001-07-01

43

Lithium Adsorption on Hexagonal Boron Nitride Nanosheet Using Dispersion-Corrected Density Functional Theory Calculations  

NASA Astrophysics Data System (ADS)

Single lithium (Li) atom adsorption behavior on hexagonal boron nitride (h-BN) nanosheet was investigated using the first-principles density functional theory (DFT) with the semi-empirical Grimme DFT-D2 approach, which allows a description of London dispersive interaction. The single Li atom was found to be strongly physisorbed on the h-BN nanosheet with dispersion-corrected DFT calculation, while a very weak bonding, close to non-bonding, between the adsorbed Li and h-BN was calculated with conventional DFT calculation. Through analyzing the charge density and the electron density of states of the Li/h-BN system, our calculations demonstrate that the dispersion-corrected DFT calculations give more reasonable predictions for a weakly-bonded adsorption system than conventional DFT calculations, which are unable to precisely describe the system due to absence of a dispersive interaction description.

Hwang, Yubin; Chung, Yong-Chae

2013-06-01

44

Structure of lithium-boron alloys and their performance as potential anodes for high power molten salt batteries  

Microsoft Academic Search

Anodic discharge curves in the LiCl-KCl eutectic melt have been obtained for two lithium-boron alloys (70 and 80 weight % Li) between 673 and 873 K (400 and 600 C) and from 2-8 A\\/sq cm. The behavior of Li contained in wicks of porous Ni was also studied for comparison. Calculated Li contents for Li-B alloy anodes, at the main

S. D. James; L. E. Devries

1976-01-01

45

Synthesis of long chain alkyl glyceryl ethers from triglycerides using boron trifluoride etherate and lithium aluminum hydride  

Microsoft Academic Search

A procedure for direct conversion of long chain triglycerides to their corresponding ether derivatives has been accomplished\\u000a using a combination of lithium aluminum hydride and boron trifluoride etherate. Reaction products obtained from reduction\\u000a of tristearin or trimyristin were isolated by thin layer and column chromatography and identified using infrared spectroscopy.\\u000a Glyceryl triethers, glyceryl monoethers, and aliphatic alcohols were the major

H. C. Go; A. L. Branen

1975-01-01

46

SYNTHESIS OF A NEW FAMILY OF FLUORINATED BORONATE COMPOUNDS AS ANION RECEPTORS AND STUDIES OF THEIR USE AS ADDITIVES IN LITHIUM BATTERY ELECTROLYTES.  

SciTech Connect

Numerous studies have been done on developing new electrolytes for lithium batteries with high ionic conductivity, and good chemical and electrochemical stability. In addition to the research on new salts and solvents, the use of cation receptors to reduce ion pairing in non-aqueous electrolytes has been considered as an approach to improve the properties of electrolytes. Although both cation and anion receptors enhance the dissociation of ion pairs and increase the conductivity of electrolytes, the use of anion receptors is more attractive for a lithium battery electrolyte because anion receptors increase the lithium transference number in the electrolyte. However, most available neutral anion receptors complex with anions through hydrogen binding and cannot be used in lithium batteries. Recently, we have reported on synthesis of a series of new neutral boron compounds as anion receptors based on the idea that electron-deficient boron would complex the anion of the ion pair. The anion complexation effect of these boron compounds was further enhanced by attaching electron-withdrawing groups. Here we report synthesis of another new family of boronate compounds. The effect of these new compounds on conductivity of lithium salts in non-aqueous solution was studied. The molecular weights of these new boronate compounds are lower than our previously reported boron compounds. Therefore, their effects on conductivity enhancement are superior. They also display high electrochemical stability up to 5 V.

MCBREEN,J.; LEE,H.S.; YANG,X.Q.

2001-06-08

47

Synthesis and studies of boron based anion receptors and their use in non-aqueous electrolytes for lithium batteries  

SciTech Connect

A new family of anion receptors based on boron compounds has been synthesized. These compounds can be used as anion receptors in lithium battery electrolytes and can greatly increase solubility and ionic conductivities of various lithium salts, such as LiF, LiCl, CF{sub 3}COOLi and C{sub 2}F{sub 5}COOLi, in DME solutions. Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy studies show that Cl{sup {minus}} anions of LiCl are complexed with these compounds in DME solutions. The electrochemical stability of lithium salts and one of the boron compounds in deferent solvents was studied. For the first time, LiF has been successfully used as conducting salt in a novel electrolyte with this boron compound as an additive in DME. A rechargeable Li/LiMn{sub 2}O{sub 4} cell using this electrolyte was successfully cycled 51 times. However, the capacity fades with cycling due to decomposition of the solvent. The cycling performance of the battery was greatly improved by replacing DME with PC-EC-DMC as the solvent.

Sun, X.; Yang, X.Q.; Lee, H.S.; McBreen, J. [Brookhaven National Lab., Upton, NY (United States); Choi, L.S. [Naval Research Lab., Washington, DC (United States)

1998-12-31

48

B - Be (Boron - Beryllium)  

NASA Astrophysics Data System (ADS)

This document is part of Volume 12 Phase Equilibria, Crystallographic and Thermodynamic Data of Binary Alloys', Subvolume B 'B - Ba Cu - Zr, Supplement to Subvolumes IV/5B, IV/5C and IV/5D', of Landolt-Brnstein - Group IV 'Physical Chemistry'.

Predel, B.

49

Enthalpies of Mixing in Liquid Beryllium Fluoride-Alkali Fluoride Mixtures.  

National Technical Information Service (NTIS)

The integral enthalpies of mixing of the liquid mixtures of beryllium fluoride with lithium fluoride, potassium fluoride, and rubidium fluoride have been determined calorimetrically at 862C. The beryllium fluoride-lithium fluoride system has an S-shaped e...

J. L. Holm O. J. Kleppa

1968-01-01

50

Boron  

MedlinePLUS

... who do not get much magnesium in their diet. Among younger women, the effect appears to be greater in women ... mg of boron per 2000 kcal per day. Diets considered to be low in boron provide ... pregnant or breast-feeding women over 19 years of age. For adolescents 14 ...

51

Observing Boron in Metal-Poor Stars  

NASA Astrophysics Data System (ADS)

By combining information on the abundances of the light elements, lithium, beryllium, and boron, in the same stars, a more consistent picture of their production, evolution, and depletion can be achieved. The analysis of the boron spectral region (2500 AA) in a new sample of stars, for which Li and Be abundances had already been measured, is presented. Special attention is devoted to discuss the associated uncertainties and to estimate the accuracy achievable when measuring boron. These new 6 data points enlarge by almost 50% our previous B sample (cf Duncan et al. 1997), and give us the opportunity to draw firmer conclusions as far as production mechanisms and evolutionary history are concerned. Our simultaneous knowledge of LiBeB for all the targets is a powerful diagnostic for testing depletion and internal mixing predicted by different stellar structure models.

Primas, F.

52

Boron and lithium isotopic composition in chondrules from the mokoia meteorite  

Microsoft Academic Search

Introduction: Large Boron isotopic variations have been reported in individual chondrules from several meteorites [1, 2]. These variations were interpreted as resulting from the incomplete mixing of two isotopically distinct sources of Boron. Spallation is the only known nucleosynthetic process that can yield Boron in substantial amounts at the scale of the Universe. Therefore it has been proposed that the

F. Robert; M. Chaussidon

2003-01-01

53

Beryllium Toxicity  

MedlinePLUS

... icio.us Digg Facebook Google Bookmarks Yahoo MyWeb Beryllium Toxicity Patient Education Care Instruction Sheet Course : WB ... Patient Education Sheet [PDF - 48 KB] What Is Beryllium? Beryllium is a mineral found in nature. It ...

54

Comparative studies of the electrochemical and thermal stability of two types of composite lithium battery electrolytes using boron-based anion receptors  

Microsoft Academic Search

Comparative studies were done on two new types of boron based anion receptors, tris(pentafluorophenyl) borane (TFPB) and tris(pentafluorophenyl) borate (TFPBO), regarding conductivity enhancement, and electrochemical and thermal stability when used as additives in composite electrolytes for lithium batteries. Both additives enhance the ionic conductivity of electrolytes of simple lithium salts, LiF, CFCOLi, and CFCOLi in several organic solvents\\/ The electrochemical

X. Sun; H. S. Lee; X. Q. Yang; J. McBreen

1999-01-01

55

Comparative Studies of the Electrochemical and Thermal Stability of Composite Electrolytes for Lithium Battery Using Two Types of Boron-Based Anion Receptors  

Microsoft Academic Search

Comparative studies were done on two new types of boron based anion receptors, tris(pentafluorophenyl) borane (TFPB) and tris(pentafluorophenyl) borate (TFPBO), regarding conductivity enhancement electrochemical and thermal stability when used as additives in composite electrolytes for lithium batteries. Both additives enhance the ionic conductivity of electrolytes of simple lithium salts, LiF, CFCOLi and CFCOLi in several organic solvents. The electrochemical windows

X. Q. Yang; H. S. Lee; X. Sun; J. McBreen

1999-01-01

56

A new set of HST boron observations. I. Testing light elements stellar depletion  

Microsoft Academic Search

A sample of 7 new stars ranging in metallicity from [Fe\\/H]=-2.0 to [Fe\\/H]=-0.75 has been analyzed in the boron spectral region. The spectra were observed with the Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST). The targets were selected on the basis of their lithium and beryllium abundances in order to investigate in a more complete way

F. Primas; D. K. Duncan; R. C. Peterson; J. A. Thorburn

1999-01-01

57

Boron in Very Metal-Poor Stars: Production of Light Elements in the Early Galaxy  

Microsoft Academic Search

We propose to derive the boron abundances in two very metal- deficient stars (-2.4>=[Fe\\/H]>=-2.9) by observing the B I 2496.7 A line with the G270M\\/SSA configuration. The abundances will be computed under NLTE conditions. Both stars have also accurate determinations of lithium (including 6Li for one of them), beryllium and oxygen abundances, which will allow us to compute and interpret

Ramon Lopez

1995-01-01

58

Boron in chondritic meteorites  

Microsoft Academic Search

Alpha-track images (ATI), prepared by etching neutron-irradiated cellulose nitrate films attached to polished thin sections of meteorites, provide useful qualitative maps of boron and lithium distribution. However, extreme care must be taken to avoid contamination during preparation, particularly by boron in diamond polishing paste. Boron and lithium are virtually absent from chondrules, metal and sulfide grains in carbonaceous and ordinary

D. M. Shaw; M. D. Higgins; R. W. Hinton; M. G. Truscott; T. A. Middleton

1988-01-01

59

Boron-substituted manganese spinel oxide cathode for lithium ion battery  

Microsoft Academic Search

An attempt has been made to synthesize boron-substituted cubic spinel through solid state (SS) and solution route (SR) techniques. The synthesized spinels have been examined for their physical and electrochemical characteristics through ex situ-X-ray diffractometry (XRD) and SEM, as well as by chargedischarge cycling and diffusion coefficient measurements. X-ray diffraction reveals boron elimination from boron-substituted spinel (SR-B spinel) resulting in

A Veluchamy; H Ikuta; M Wakihara

2001-01-01

60

Lithium and boron isotopes in illite-smectite: The importance of crystal size  

NASA Astrophysics Data System (ADS)

Clay minerals record chemical data about the past, acting like natural computer memory chips. To retrieve the data we must understand how they are stored. To achieve this we have examined the isotopic information revealed by two trace elements, lithium and boron, that are incorporated into the common clay minerals illite-smectite (I-S) during diagenesis. We used hydrothermal experiments at 300C, 100 MPa, to speed up the reaction of smectite to illite that normally occurs during slow (10-100 Ma) sediment burial. During illitization, Li substitutes into the octahedral sites and B enters the tetrahedral sites of the silicate framework. Both Li and B are also adsorbed in the interlayer of smectite, but Li is preferred over B in the exchange sites. To determine the equilibrium isotope fractionation of the two trace elements it is important to remove these adsorbed interlayer species. By measuring the isotopic composition of Li and B in the silicate framework during reaction, we can address the relative timing of element exchange in the different crystallographic sites. Furthermore, because illitization of smectite is a crystal growth process (not an isomorphous replacement) we have examined the effect of crystal size on the isotope fractionation. The results show that Li and B approach an isotopic steady state when R1 ordering occurs, long before oxygen isotopes equilibrate with the fluid. The isotopic fractionation (? mineral-water) for Li (0.989) is similar to that for B (0.984) at 300C. However, when separated into <0.2, 0.2-2.0, and >2.0 ?m fractions, there are significant differences in measured isotope ratios by as much as 9. Crystal growth mechanisms and surface energy effects of nanoscale crystals may explain the observed isotopic differences. The fact that different crystals equilibrate at different rates (based on size) may be applied to natural samples to reveal the changing paleofluid history, provided we understand the conditions of equilibrium. This has very important implications for the interpretation of diagenetic environments, fluid flow, and surficial geochemical cycling.

Williams, Lynda B.; Hervig, Richard L.

2005-12-01

61

Analysis of ultratrace lithium and boron by neutron activation and mass-spectrometric measurement of 3He and 4He.  

PubMed

A new technique for analysis of lithium and boron at ultratrace concentrations (less than 10(-8)g g-1) is described. The method consists of mass-spectrometric assay of 3He from decay of tritium produced by thermal-neutron reaction on 6Li, and 4He produced by thermal-neutron reaction on 10B. Two neutron-irradiation facilities were used: the McMaster reactor, which is 235U-enriched and light-water moderated; and a graphite-moderated thermal column attached to the 235U-enriched, heavy-water-moderated core at the National Bureau of Standards (NBS) reactor. In the McMaster irradiations, fast neutrons (greater than 0.2 MeV) induce the reactions 14N(n, 3H)12C, 12C(n, alpha)9Be, 16O(n, alpha)13C, and 14N(n, alpha)11B. These reactions become serious sources of error in samples such as human blood which have very low concentrations of lithium and boron, and high concentrations of nitrogen, carbon and oxygen. In the NBS thermal column, fast-neutron reactions are virtually absent, and only corrections for thermal-neutron capture by deuterium, and thermal-neutron (n, alpha) reactions on oxygen, sulfur, chlorine, potassium, and calcium need to be taken into account. Results are presented for various actual samples including human blood and its components, and some standard biological reference materials, to provide a realistic base for other workers to judge the reliability of the method. PMID:2822629

Clarke, W B; Koekebakker, M; Barr, R D; Downing, R G; Fleming, R F

1987-01-01

62

Implications of the serpentine phase transition on the behaviour of beryllium and lithiumboron of subducted ultramafic rocks  

Microsoft Academic Search

The TotalpPlattaMalenco ophiolites in the Eastern Central Alps offer a unique opportunity to study the behaviour of Li, Be and B in ultramafic rocks in response to serpentinization and to progressive Alpine metamorphism. These units represent the remnants of a former ocean-continent transition that was intensely serpentinized during exposure on the Jurassic seafloor of the Ligurian Tethys. From north to

Flurin Vils; Othmar Mntener; Angelika Kalt; Thomas Ludwig

2011-01-01

63

Behaviour of boron, beryllium, and lithium during melting and crystallization: constraints from mineral-melt partitioning experiments  

Microsoft Academic Search

In order to provide a more substantial foundation for interpreting the behaviour of B, Be, and Li during the production and early crystallization of primitive igneous rocks, we have measured olivine-, clinopyroxene-, orthopyroxene-, and amphibole-melt partition coefficients for these elements involving broadly basaltic-andesitic melt compositions. Experiments were conducted at both one atmosphere and 1.01.5 GPa and employed a time-temperature history

J. M. Brenan; E. Neroda; C. C. Lundstrom; H. F. Shaw; F. J. Ryerson; D. L. Phinney

1998-01-01

64

Structure of lithium--boron alloys and their performance as potential anodes for high power molten salt batteries. Progress report, 1 Aug 1974--30 Jun 1975  

Microsoft Academic Search

Anodic discharge curves in the LiCl--KCl eutectic melt have been obtained for two lithium--boron alloys (70 and 80 wt % Li) between 673 and 873 K (400 and 600 C) and from 2 to 8 A\\/sq cm. The behavior of Li contained in wicks of porous Ni was also studied for comparison. Calculated Li contents for Li--B alloy anodes, at

S. D. James; L. E. DeVries

1976-01-01

65

Lithium-doped (4,4) Boron nitride nanotube: Density functional theory study of N and B nuclear magnetic shielding and electric field gradient tensors  

Microsoft Academic Search

First principle values of nuclear magnetic shieldings and nuclear quadrupole coupling constants of B and N nuclei via density functional theory (DFT) were calculated for a hydrogen-capped (4,4) single-walled boron nitride nanotube (BNNT) (raw model) and a lithium-doped derivative of it (Li-doped model). The models were first fully relaxed and then the CQ and nuclear magnetic shielding tensor calculations were

Ahmad Seif; Asadollah Boshra; Majid Seif

2009-01-01

66

Depth distribution of boron determined by slow neutron induced lithium ion emission  

Microsoft Academic Search

Neutron Depth Profiling (NDP) has been established as a non-destructive technique to determine the near surface distribution of light elements, particularly boron. By analyzing the residual energy spectrum of the emitted particles of known initial energy as a result of nuclear capture within the target material, information about the site and amount of the reactions can be deduced. In the

Huaiyu H. Chen-Mayer; George P Lamaze

1998-01-01

67

Geothermal constraints on enrichment of boron and lithium in salt lakes: An example from a river-salt lake system on the northern slope of the eastern Kunlun Mountains, China  

NASA Astrophysics Data System (ADS)

Some rivers on the northern slope of the eastern Kunlun Mountains in the Qaidam Basin, China, show very high concentrations of boron and lithium. Correspondingly, the salt lakes fed by these rivers show an unusual enrichment of boron and lithium, and become an important economic resource. The origin of boron and lithium has long been debated. The aim of this study is to analyze the water chemistry and hydrogen and oxygen isotopic composition of river water to understand the unusual enrichment of boron and lithium in the salt lakes of the Qaidam Basin. Oxygen and hydrogen isotope data show that the source of river water in the winter and summer originates from the Kunlun Mountain ice and snow melt water, respectively. The water chemistry shows that boron and lithium contents are high but little variable with seasons in the Nalenggele River and Wutumeiren River waters. By contrast, other rivers have much lower lithium and boron contents. Moreover, the contents of B3+ and Li+ in the river loads or bed sands show little difference amongst the rivers. This indicates that removal by adsorption or input by surface rock weathering is not the main controlling factor of the B3+ and Li+ variation in the rivers. Rivers with high B3+ and Li+ content are chemically similar to geothermal waters in the Tibetan Plateau. In addition, the source area of the Nalenggele River is located in a collision zone of the Kunlun Mountains and Altun Mountains. Large and deep faults can serve as conduits for geothermal fluids. Thus, deep geothermal waters in the source area can easily migrate to the surface and discharge as springs feeding the rivers. They are an important source of B3+ and Li+ to the rivers. The abnormally high contents of B3+ and Li+ in the Nalenggele and Wutumeiren Rivers also suggest that the geothermal source area may be a future target for boron and lithium resources.

Tan, Hongbing; Chen, Jun; Rao, Wenbo; Zhang, Wenjie; Zhou, Huifang

2012-06-01

68

High power accelerator-based boron neutron capture with a liquid lithium target and new applications to treatment of infectious diseases.  

PubMed

A new conceptual design for an accelerator-based boron neutron capture therapy (ABNCT) facility based on the high-current low-energy proton beam driven by the linear accelerator at SARAF (Soreq Applied Research Accelerator Facility) incident on a windowless forced-flow liquid-lithium target, is described. The liquid-lithium target, currently in construction at Soreq NRC, will produce a neutron field suitable for the BNCT treatment of deep-seated tumor tissues, through the reaction (7)Li(p,n)(7)Be. The liquid-lithium target is designed to overcome the major problem of solid lithium targets, namely to sustain and dissipate the power deposited by the high-intensity proton beam. Together with diseases conventionally targeted by BNCT, we propose to study the application of our setup to a novel approach in treatment of diseases associated with bacterial infections and biofilms, e.g. inflammations on implants and prosthetic devices, cystic fibrosis, infectious kidney stones. Feasibility experiments evaluating the boron neutron capture effectiveness on bacteria annihilation are taking place at the Soreq nuclear reactor. PMID:19406650

Halfon, S; Paul, M; Steinberg, D; Nagler, A; Arenshtam, A; Kijel, D; Polacheck, I; Srebnik, M

2009-03-27

69

Beryllium Technology Research in the United States  

SciTech Connect

While most active research involving beryllium in the United States remains tied strongly to biological effects, there are several areas of technology development in the last two years that should be mentioned. (1) Beryllium disposed of in soil vaults at the Idaho National Laboratory (INL) Radioactive Waste Management Complex (RWMC) has been encapsulated in-situ by high-temperature and pressure injection of a proprietary wax based material to inhibit corrosion. (2) A research program to develop a process for removing heavy metals and cobalt from irradiated beryllium using solvent extraction techniques has been initiated to remove components that prevent the beryllium from being disposed of as ordinary radioactive waste. (3) The JUPITER-II program at the INL Safety and Tritium Applied Research (STAR) facility has addressed the REDOX reaction of beryllium in molten Flibe (a mixture of LiF and BeF2) to control tritium, particularly in the form of HF, bred in the Flibe by reactions involving both beryllium and lithium. (4) Work has been performed at Los Alamos National Laboratory to produce beryllium high heat flux components by plasma spray deposition on macro-roughened substrates. Finally, (5) corrosion studies on buried beryllium samples at the RWMC have shown that the physical form of some of the corroded beryllium is very filamentary and asbestos-like. This form of beryllium may exacerbate the contraction of chronic beryllium disease.

Glen R. Longhurst; Robert A. Anderl; M. Kay Adleer-Flitton; Gretchen E. Matthern; Troy J. Tranter; Kendall J. Hollis

2005-02-01

70

Boron and lithium isotopic composition in chondrules from the mokoia meteorite  

NASA Astrophysics Data System (ADS)

Introduction: Large Boron isotopic variations have been reported in individual chondrules from several meteorites [1, 2]. These variations were interpreted as resulting from the incomplete mixing of two isotopically distinct sources of Boron. Spallation is the only known nucleosynthetic process that can yield Boron in substantial amounts at the scale of the Universe. Therefore it has been proposed that the two sources observed in chondrules correspond to two different types of spallation reactions, namely at high and low energies. Indeed, in the case of Boron, the 11B/10B ratio is sensitive to the energy at which the spallation reaction takes place. Since this report of large B isotopic variations in chondrules, two observations have allowed to identify the natural conditions under which at least one of such spallation reactions may have taken place in the early solar system. First, X-ray observations of T-Tauri stars have revealed daily outbursts which mimic the present day solar activity during the emission of flares [3]. Second, the decay product (i.e. 10B) of the short lived radio-isotope 10Be was discovered in Calcium-Aluminum-rich inclusions (CAIs) [4]. This is an indication that spallation did occurr in the solar system, shortly (i.e. less than a few million years) before the formation of the CAIs. In addition the possible occurrence of 7Be in CAIs suggests that this duration can be as short as a few months [5]. Sampling and Results: In the 8 chondrules from Mokoia, the ?11B values range between -396.8 ppm and -0.67.8 ppm (2 sigma). In one Boron depleted area of one chondrule, the ?11B value was found to be as low as -68.5 ppm and -61.5 ppm (29; 2 sigma). In one chondrule from Mokoia the ?11B values range between -33.75.4 ppm and -3.85.4 ppm. These data confirm with a resolution of ? 6 ppm the presence of a significant Boron isotopic heterogeneity,.The ?^7Li were also measured along with the ^delta11B. They range from -53.72.4 and -0.151.6 ppm (2 sigma) in the 8 chondrules of the Mokoia meteorite. Therefore the heterogeneity in B has its counterpart for Li. Interpretation: A two end member mixing model members can be proposed : ?11B ?0 ppm and ?11B<= -70 ppm. The value of 0 ppm is still significantly different from the matrix value reported by [6] (+19.2 ppm) and thus the possible contamination of the chondrule by their surrounding matrix is highly unlikely. The second end member should have ?11B and ?^7Li values le-70 ppm and le-50 ppm, respectively, resulting from Li and B produced at high energy by spallation reactions (E >= 100 MeV/nucleon, ?11B =-375 ?^7Li = -830 ppm). References: [1] Chaussidon M., Robert F. (1995) Nature 374, 337-339. [2] Chaussidon M. and Robert F. (1998) Earth Planet Sci. Lett. 164, 577-589. [3] Montmerle T. (1999) MPE Report : Astronomy with Radioactivities, 225-236. [4] McKeegan K., Chaussidon M., Robert F. (2000) Science 289, 1334-1337. [5] Chaussidon M., Robert F. McKeegan K. (2002) Abst. 33th LPSC #1563 [6] Hoppe et al., (2001) MAPS, 36, 1331-1343. [7] Zhai M et al., (1996) Geochim. Cosmochim. Acta 60, 4877-4881.

Robert, F.; Chaussidon, M.

2003-04-01

71

Boron in G64-12: Higher Big Bang Lithium or Signature of the Nu-Process?  

NASA Astrophysics Data System (ADS)

The extremely metal-poor { Fe/H -3.3 } star G64-12 shows a remarkable lithium {Li} abundance that is about 2 times larger than those seen in other warm metal-poor stars, from which the Big Bang Li abundance is inferred. This star's enhanced Li has resulted from either 1. Galactic Li enrichment from a lower Big Bang value, or 2. stellar depletion from a higher Big Bang value, with significant cosmological implications. We argue against two of the three prominent mechanisms of Galactic Li enrichment, leaving the theoretical Nu-process in Type II supernovae as the sole viable mechanism. This mechanism's crisp signature is the concomitant production of copious amounts of boron {B}; if the Nu-process enriched the material out which G64-12 formed with the extra Li observed today, then this star should also exhibit a large detectable B overabundance. B in G64-12 can only be observed from space, using HST/STIS. If this star's STIS-based B abundance lies above the established B-Fe trend, this would be the first observational evidence for the Nu-process. But if its B abundance lies near the B-Fe trend, this would provide direct evidence that G64-12 is an elusive fossil of a Big Bang Li abundance about 0.3 dex above currently favored values, providing consistency in standard Big Bang Nucleosynthesis between Li and D {but not 4He}. EITHER RESULT would be of fundamental importance to Astronomy.

Deliyannis, Constantine

2001-07-01

72

Development of beryllium mirror turning technology  

NASA Astrophysics Data System (ADS)

Because of the unique properties of beryllium (Be) and the advantages of single point turning, a development program has been instituted to single point turn beryllium as a means to produce optics. Initial effort to diamond turn beryllium resulted in less than desirable results and development efforts were directed at finding a more suitable tool material. Both single and polycrystalline tool materials were evaluated and cubic boron nitride (CBN) was found to produce the better results. Tool wear has been the primary limitation in precision machining beryllium and advances have allowed a two order-of-magnitude reduction in this problem. After considerable efforts, results with CBN appear to be approaching a limit, and diamond, as tool material, was re-evaluated with promising results. A development program is now under way to determine if diamond may be used to machine larger and more complex beryllium parts.

Arnold, J. B.

1991-04-01

73

Development of beryllium mirror turning technology  

NASA Astrophysics Data System (ADS)

Because of the unique properties of beryllium (Be) and the advantages of single point turning, a development program has been instituted to single point turn beryllium as a means to produce optics. Initial effort to diamond turn beryllium resulted in less than desirable results and development efforts were directed at finding a more suitable tool material. Both single and polycrystalline tool materials were evaluated and cubic boron nitride (CBN) was found to produce the better results. Tool wear has been the primary limitation in precision machining beryllium and advances have allowed a two order-of-magnitude reduction in this problem. After considerable efforts, results with CBN appear to be approaching a limit, and diamond, as tool material, was re-evaluated with promising results. A development program is now under way to determine if diamond may be used to machine larger and more complex beryllium parts.

Arnold, Jones B.

1991-09-01

74

Method for welding beryllium  

DOEpatents

A method is provided for joining beryllium pieces which comprises: depositing aluminum alloy on at least one beryllium surface; contacting that beryllium surface with at least one other beryllium surface; and welding the aluminum alloy coated beryllium surfaces together. The aluminum alloy may be deposited on the beryllium using gas metal arc welding. The aluminum alloy coated beryllium surfaces may be subjected to elevated temperatures and pressures to reduce porosity before welding the pieces together. The aluminum alloy coated beryllium surfaces may be machined into a desired welding joint configuration before welding. The beryllium may be an alloy of beryllium or a beryllium compound. The aluminum alloy may comprise aluminum and silicon.

Dixon, Raymond D. (Los Alamos, NM); Smith, Frank M. (Espanola, NM); O' Leary, Richard F. (Los Alamos, NM)

1997-01-01

75

Beryllium disease  

SciTech Connect

After two workers at the nuclear weapons plant at Oak Ridge National Laboratory in Tennessee were diagnosed earlier this year with chronic beryllium disease (CBD), a rare and sometimes fatal scarring of the lungs, the Department of Energy ordered up a 4-year probe. Now, part of that probe has begun - tests conducted by the Oak Ridge Associated Universities' Center for Epidemiological Research measuring beryllium sensitivity in 3,000 people who've been exposed to the metal's dust since Manhattan Project managers opened the Y-12 plant at Oak Ridge in 1943. Currently, 119 Y-12 employees process beryllium, which has a number of industrial uses, including rocket heat shields and nuclear weapon and electrical components. The disease often takes 20 to 25 years to develop, and the stricken employees haven't worked with beryllium for years. There is no cure for CBD, estimated to strike 2% of people exposed to the metal. Anti-inflammatory steroids alleviate such symptoms as a dry cough, weight loss, and fatigue. Like other lung-fibrosis diseases that are linked to lung cancer, some people suspect CBD might cause some lung cancer. While difficult to diagnose, about 900 cases of CBD have been reported since a Beryllium Case Registry was established in 1952. The Department of Energy (DOE) estimates that about 10,000 DOE employees and 800,000 people in private industry have worked with beryllium.

Not Available

1991-12-20

76

Theoretical study of beryllium structures analogous to crown ethers  

Microsoft Academic Search

In this paper we present the electronic and structural study of beryllium molecules analogous to crown ethers, where the CH2 groups have been exchanged for beryllium atoms. The resulting structures are completely planar, unlike crown ethers, that the latter are bi-dimensional and flexible. In addition, the coordination of lithium atoms (as Li+), which are arranged directionally to each oxygen atom,

Maria Esther Sanchez-Castro; Mario Sanchez-Vazquez

2011-01-01

77

Boron in Very Metal-Poor Stars: Production of Light Elements in the Early Galaxy  

NASA Astrophysics Data System (ADS)

We propose to derive the boron abundances in two very metal- deficient stars (-2.4>=[Fe/H]>=-2.9) by observing the B I 2496.7 A line with the G270M/SSA configuration. The abundances will be computed under NLTE conditions. Both stars have also accurate determinations of lithium (including 6Li for one of them), beryllium and oxygen abundances, which will allow us to compute and interpret the abundance ratios between these elements. The available data for the star HD140283 ([Fe/H]=-2.7), for which an accurate NLTE boron abundance has been derived, seem to favour the hypothesis that boron and beryllium in Population II stars were produced by cosmic ray induced spallation reactions and not by inhomogeneous big bang nucleosynthesis. These new observations, which include what is probably the most metal-poor unevolved star known for which boron can be measured with HST, together with the results obtained for HD140283, will be the most useful diagnostic used up to now to precisely constrain the different mechanisms proposed as responsible for the light element production in the early Galaxy.

Lopez, Ramon

1995-07-01

78

Beryllium weldability  

SciTech Connect

Welding processes and metallurgical considerations for beryllium welding are discussed in this review. The primary difficulties of welding beryllium are hot cracking, cracking at defects, and ductility limitation or thermally induced cracking. Solutions to these welding problems include control of the Fe/Al ratio in the base metal to reduce hot cracking, minimization of the BeO content and starting grain size to limit cracking at defects and ductility limitation cracking, and optimization of the welding process and process variables. 25 refs., 9 figs., 2 tabs.

Hill, M.A.; Damkroger, B.K.; Dixon, R.D. (Los Alamos National Lab., NM (USA)); Robertson, E. (Air Force Office of Scientific Research, Washington, DC (USA))

1990-01-01

79

The Toxicology of Beryllium.  

National Technical Information Service (NTIS)

Review of the physiology, toxicology, pathology, analytical determination, and experimental testing of beryllium and beryllium compounds. Tabulated data are given for the effect, body distribution, excretion and blood levels of various beryllium compounds...

I. R. Tabershaw

1972-01-01

80

Method for welding beryllium  

DOEpatents

A method is provided for joining beryllium pieces which comprises: depositing aluminum alloy on at least one beryllium surface; contacting that beryllium surface with at least one other beryllium surface; and welding the aluminum alloy coated beryllium surfaces together. The aluminum alloy may be deposited on the beryllium using gas metal arc welding. The aluminum alloy coated beryllium surfaces may be subjected to elevated temperatures and pressures to reduce porosity before welding the pieces together. The aluminum alloy coated beryllium surfaces may be machined into a desired welding joint configuration before welding. The beryllium may be an alloy of beryllium or a beryllium compound. The aluminum alloy may comprise aluminum and silicon. 9 figs.

Dixon, R.D.; Smith, F.M.; O`Leary, R.F.

1997-04-01

81

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50

I. Weinberg; H. W. Brandhorst Jr.

1986-01-01

82

Lithium counterdoped silicon solar cell  

Microsoft Academic Search

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50

I. Weinberg; Brandhorst H. W. Jr

1984-01-01

83

Lithium Counterdoped Silicon Solar Cell.  

National Technical Information Service (NTIS)

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. T...

I. Weinberg H. W. Brandhorst

1984-01-01

84

The effect of boron-doped on capacity of carbon cathode of rechargeable lithium-ion batteries  

Microsoft Academic Search

Purpose To focus on the development of negative materials with a large Li ion capacity. Design\\/methodology\\/approach All calculations were performed using the Own N-layered Integrated molecular Orbital and molecular Mechanics method with Becke 3-parameter, Lee, Yang, Parr for high-level treatment and with the universal force field for low-level treatment. Findings It was found that boron substitution created

S. R. Ma; Z. H. Huang; C. B. Li; G. X. Yang; C. Wang

2007-01-01

85

Comparative studies of the electrochemical and thermal stability of two types of composite lithium battery electrolytes using boron-based anion receptors  

SciTech Connect

Comparative studies were done on two new types of boron based anion receptors, tris(pentafluorophenyl) borane (TFPB) and tris(pentafluorophenyl) borate (TFPBO), regarding conductivity enhancement, and electrochemical and thermal stability when used as additives in composite electrolytes for lithium batteries. Both additives enhance the ionic conductivity of electrolytes of simple lithium salts, LiF, CF{sub 3}CO{sub 2}Li, and C{sub 2}F{sub 5}CO{sub 2}Li in several organic solvents/ The electrochemical windows of TPFB based electrolytes in ethylene carbonate-propylene carbonate-dimethyl carbonate (1:1:3, v/v) are up to 5, 4.76 V for LiF, CF{sub 3}CO{sub 2}Li, and C{sub 2}F{sub 5}CO{sub 2}Li, respectively, TPFBO has lower electrochemical stability compared to TPFB. The thermal stability of pure TFPB is better than TFPBO. Complexation with the salt improves the thermal stability of these additives. TPFB based electrolytes showed high cycling efficiencies and cycleability when they were tested in Li/LiMn{sub 2}O{sub 4} cells. TFPBO based electrolytes showed high cycling efficiencies and good cycleability when they were tested in Li/LiMn{sub 2}O{sub 4} cells. TFPBO based electrolytes were tested in Li/LiNiO{sub 2} cells; the cells delivered high discharge capacity and good cycling efficiencies. The capacity retention of the cells using TFPB based electrolytes during multiple cycling is better than those using TFPBO based electrolytes.

Sun, X.; Lee, H.S.; Yang, X.Q.; McBreen, J.

1999-10-01

86

Improved synthesis of a highly fluorinated boronic ester as dual functional additive for lithium-ion batteries.  

SciTech Connect

The electrolyte additive 2-(pentafluorophenyl)-tetrafluoro-1,3,2-benzodioxaborole (PFPTFBB, 1) was found to have a reversible redox potential at 4.43 V vs. Li{sup +}/Li. This compound can function as an overcharge protection additive as well as anion receptor for lithium-ion batteries. It has drawn a great deal of interest from industry, but its use in relatively large quantities is limited by the production challenges of tetrafluorocatechol (TFC, 3), which is the key starting chemical for the synthesis of PFPTFBB. As part of a continuous effort in our research toward improving the safety of lithium-ion batteries, we have performed the synthesis of TFC and optimized its synthesis process. The X-ray single-crystal structures of TFC and the intermediate product 5,6,7,8-tetrafluoro-1,4-benzodioxane (4) during the process of PFPTFBB synthesis are reported for the first time. Also presented is the lithium ion cell performance of PFPTFBB as redox shuttle in various electrolyte systems.

Weng, W.; Zhang, Z.; Schlueter, J. A.; Redfern, P. C.; Curtiss, L. A.; Amine, K. (Center for Nanoscale Materials); ( CSE); ( MSD)

2011-02-01

87

The role of aqueous fluids in the slab-to-mantle transfer of boron, beryllium, and lithium during subduction: experiments and models  

Microsoft Academic Search

The low atomic mass elements B, Be, and Li are viewed as sensitive tracers of the involvement of subducted materials in the genesis of island arc magmas. In order to better assess the role of dense aqueous fluids in the slab-to-mantle transfer of these elements during subduction, measurements have been made of partition coefficients for B, Be, and Li between

James M. Brenan; Frederick J. Ryerson; Henry F. Shaw

1998-01-01

88

The role of aqueous fluids in the slab-to-mantle transfer of boron, beryllium, and lithium during subduction: Experiments and models  

SciTech Connect

The low atomic mass elements B, Be, and Li are viewed as sensitive tracers of the involvement of subducted materials in the genesis of island arc magmas. In order to better assess the role of dense aqueous fluids in the slab-to-mantle transfer of these elements during subduction, measurements have been made of partition coefficients for B, Be, and Li between aqueous fluid and minerals likely to be present in the basaltic portion of the downgoing slab, namely clinopyroxene and garnet. Experiments at 900 C and 2.0 GPa reveal that the average clinopyroxene-fluid partition coefficient for Be ({approximately}2) exceeds that for either Li ({approximately}0.2) or B ({approximately}0.02) and values are 100{times} (B,Li) to 1,000{times} (Be) larger than partition coefficients for garnet. Clinopyroxene-fluid partition coefficients were found to vary with the alumina content of run-product clinopyroxenes, but this variation is interpreted to reflect the specific exchange reaction that governs the incorporation of these elements into the pyroxene structure, and not mineral-fluid disequilibrium. Calculations indicate that by the time the slab reaches a depth of 200 km, B/Be and B/Nb in the dehydration residue has been reduced to {approximately}5--12% of initial values. Thus, the preferential loss of B during dehydration is viewed as a viable mechanism to prevent the excess B acquired during near-surface alteration of oceanic crust from being cycled into the mantle, thereby maintaining the distinction in B/Be and B/Nb for mantle and crustal reservoirs.

Brenan, J.M. [Univ. of Toronto, Ontario (Canada). Dept. of Geology; Ryerson, F.J.; Shaw, H.F. [Lawrence Livermore National Lab., CA (United States)

1998-10-01

89

Extractive Metallurgy of Beryllium  

Microsoft Academic Search

A comprehensive review of the extractive metallurgy of beryllium is presented. Due to the strategic importance and element of secrecy surrounding the metal, any open literature on beryllium is rather limited. However, this review has been made to cover all important aspects of beryllium extraction technology namely, resources of the metal; processing of ores; reduction of fluoride and oxide to

C. K. GUPTA; S. SAHA

2002-01-01

90

Extractive Metallurgy of Beryllium  

Microsoft Academic Search

A comprehensive review of the extractive metallurgy of beryllium is presented. Due to the strategic importance and element of secrecy surrounding the metal, any open literature on beryllium is rather limited. However, this review has been made to cover all important aspects of beryllium extraction technology namely, resources of the metal; processing of ores; reduction of fluoride and oxide to

C. K. GUPTA; S. SAHA

2001-01-01

91

Lithium counterdoped silicon solar cell  

SciTech Connect

The resistance to radiation damage of an n(+)p boron doped silicon solar cell is improved by lithium counterdoping. Even though lithium is an n-dopant in silicon, the lithium is introduced in small enough quantities so that the cell base remains p-type. The lithium is introduced into the solar cell wafer by implantation of lithium ions whose energy is about 50 keV. After this lithium implantation, the wafer is annealed in a nitrogen atmosphere at 375 C for two hours. NASA

Weinberg, I.; Brandhorst, H.W., Jr.

1984-11-01

92

Boron and Lithium isotopic signatures in rivers as proxies of silicate weathering regimes : the example of the Mackenzie river system, Canada (Invited)  

NASA Astrophysics Data System (ADS)

Large river systems integrate the diversity of weathering and transport conditions as well as the bedrock composition. They provide a unique opportunity to unravel the parameters operating within the critical zone of the Earth globally. Here, we present B and Li isotopes data measured in both the complementary soluble and suspended phases in the Mackenzie river (Northeastern Canada), one of the world largest river the Mackenzie river basin. An interesting parallel can be made between these two isotopic systems: - Both elements are predominantly derived from the weathering of silicate minerals and are thus relatively less affected by lithology. - Both elements are considerably fractionated during water/rock interactions during which they partition between the solid and liquid phases. Their respective geochemical signature is then strongly dependent upon geomorphic features of the Basin (mountains, plains, shield area). - Both isotopic systems are greatly fractionated by a preferential release in solution of the heavy isotope, which considerably help investigating the nature and magnitude of the weathering and transport processes in action. - And finally, strong evidences indicate that local groundwaters may control their transfer through the basin and imprint their isotopic signature as well. Because, boron and lithium have very different chemical behaviors, in particular distinct surface properties, their respective isotopes behave distinctly under same reactive transport conditions. This feature results in the absence of correlation between this two isotopic systems despite their apparent similarities. Then the coupled investigation of the Li and B isotopes during chemical weathering adds strong constraints on the weathering regimes operating at large scale and clearly encourages the multi-isotopic tracing of the critical zone processes.

Gaillardet, J.; Millot, R.; Lemarchand, D.; Vigier, N.

2009-12-01

93

Boron-lithium relationships in rhyolites and associated thermal waters of young silicic calderas, with comments on incompatible element behavior  

SciTech Connect

This study had three goals: (1) to study B distribution in a rhyolitic volcanic sequence already extensively investigated for other elements; (2) to interpret the joint behavior of B and Li during the interaction of such rocks with subsurface waters; and (3) to assess the manner in which water affects the behavior of incompatible elements such as B and Gd. New B, Gd, and Sm analyses have been made on a suite of Yellowstone rhyolites, including fresh and partially devitrified glassy obsidian from surface exposures of several flows, a drill-core of increasing degrees of alteration in the Biscuit Basin Flow, and two drill-cores from other flows. Within the Biscuit Basin Flow, the Sm and Gd concentrations remain rather constant and behave conservatively, independent of alteration. Boron decreases from about 10 to 3 ppm with progressive alteration, and Li increases from about 40 ppm by a factor of 2-3 in the most altered rocks. Obsidians from the Valles and Long Valley calderas show greater Li loss during alteration. All the rhyolitic rocks lose B during aqueous alteration; the waters acquire both B and Li, but proportionately much more B. Natural waters of all kinds, including those from the three calderas, show six orders of magnitude range in aqueous B and Li, with a high degree of linear correlation and an average ratio B/Li essentially constant at 4.0. The linearity mainly expresses processes of dilution and concentration: reactions specific to B or Li engender waters with deviating B/Li.

Shaw, D.M. (McMaster Univ., Hamilton, Ontario (Canada)); Sturchio, N.C. (Argonne National Lab., IL (United States))

1992-10-01

94

Parabolic lithium refractive optics for x rays  

Microsoft Academic Search

Excellent x-ray optics for photons at around 10 keV can be expected with lithium metal. One of the best compound refractive lens designs [Lengeler &etal;, J. Appl. Phys. 84, 5855 (1998)] is now produced routinely in aluminum, and more recently has been demonstrated using beryllium [M. Kuhlmann &etal; (unpublished)]. Here, we report a similar refractive lens made from lithium. At

N. R. Pereira; E. M. Dufresne; R. Clarke; D. A. Arms

2004-01-01

95

The Evolution of Beryllium and Boron  

NASA Astrophysics Data System (ADS)

The observations of Be and B in extreme metal-poor Population II stars show that these elements have a Galactic (rather than cosmological) nucleosynthesis source. In particular, Be and B are probably made in one or more kinds of spallation processes, due to cosmic-ray interactions with the interstellar medium and neutrino interactions in supernovae. Consequently, the galactic chemical evolution of Be and B provides unique information about the origin and history of cosmic rays. However, the current data are equivocal about the nature of Be and B origin, as encoded in the primary or secondary (linear or quadratic) scaling with metallicity. The results a careful analysis of the trends among Be, B, Fe, and O are presented, with an emphasis on the importance of the halo star O/Fe relation for interpreting the Be-Fe and B-Fe trends. If O/Fe is constant, then an unconventional cosmic ray origin or component is needed in the early Galaxy. On the other hand, if O/Fe is not constant, as recent data suggest, then the data could indicate a standard cosmic ray origin, wherein the abundances of cosmic rays scale with those of the interstellar medium. Future observational tests are suggested which can distinguish several proposed scenarios of Li, Be, B, and cosmic ray origin.

Fields, B.

1999-05-01

96

Minerals Yearbook, 1988. Beryllium  

SciTech Connect

Domestic production and consumption of beryllium ore decreased in 1988, but beryllium alloys garnered new applications in automotive electronics and increased their usage in computer systems. Following the significant increase in exports of beryllium in 1987, exports in 1988 returned to normal levels. Beryl ore imports declined significantly and reflected a decrease in apparent consumption. Contents include: Domestic data coverage; legislation and government programs; domestic production; consumption and uses; prices and specifications; foreign trade; world capacity; world review; and technology.

Kramer, D.A.

1988-01-01

97

Observing Boron in Metal-Poor Stars  

NASA Astrophysics Data System (ADS)

A new sample of 7 stars ranging in metallicity from [Fe/H] = -2.0 to [Fe/H] = -0.75 has been analyzed in the boron spectral region. The targets were selected according to the availability (in the literature) of their lithium and beryllium abundances, because the simultaneous knowledge of LiBeB in the same targets is a powerful diagnostic for testing depletion and internal mixing predicted by different stellar structure models. Two stars (HD 94028 and HD 194598), characterized by similar Li contents, are found to have also similar B abundances, despite a 0.3 dex difference in their Be abundances claimed by Thorburn and Hobbs (1996). Four stars out of 7 are characterized by strongly depleted Li and Be abundances: 2 of them (HD 2665 and HD 3795) are also significantly B-depleted, while two others (HD 106516 and HD 221377) have near normal B abundances despite being depleted by a factor ? 10 in both Li and Be abundances. These stars place strong constraints on the nature and depth of the mixing processes responsible for their light element abundances. The 7th star (HD 160617) shows the remarkable aspect of deficient B, probably deficient Be, and completely normal Li. No stellar destruction mechanism can explain this. Rather, chemical inhomogeneities in the halo could be the cause.

Primas, F.

1999-07-01

98

ZONE PURIFICATION OF BERYLLIUM  

Microsoft Academic Search

Preliminary experimental evidence is presented to show that the metallic ; impurities aluminum, iron, silicon, and beryllium oxide, as found in commercially ; pure hotpressed beryllium pewder, can be reduced to lower concentrations by zone-; purification techniques. The reduction in the concentration of aluminum to ; extremely low levels (10 ppm) is noteworthy, since earlier work demonstrated that ; aluminum

W. R. Mitchell; J. A. Mullendore; R. S. Maloof

1961-01-01

99

Beryllium Manufacturing Processes.  

National Technical Information Service (NTIS)

This report is one of a number of reports that will be combined into a handbook on beryllium. Each report covers a specific topic. To-date, the following reports have been published: (1) Consolidation and Grades of Beryllium; (2) Mechanical Properties of ...

A. Goldberg

2006-01-01

100

METHOD OF WORKING BERYLLIUM  

DOEpatents

>A process is presented for fabricating beryllium metal. The billet cf beryllium metal is sheathed with a jacket of either copper or stainless steel. It may then be worked by drawing or the like at a tcmperature of 300 to 400 C.

Macherey, R.E.

1959-02-01

101

Beryllium Sensitization Progresses to Chronic Beryllium Disease A Longitudinal Study of Disease Risk  

Microsoft Academic Search

The blood beryllium lymphocyte proliferation test is used in medical surveillance to identify both beryllium sensitization and chronic beryllium disease. Approximately 50% of individuals with beryllium sensitization have chronic beryllium disease at the time of their initial clinical evaluation; however, the rate of progression from beryllium sensitization to chronic beryllium disease is unknown. We monitored a cohort of beryllium-sensitized patients

Lee S. Newman; Margaret M. Mroz; Ronald Balkissoon; Lisa A. Maier

2004-01-01

102

Beryllium copper alloy (2%) causes chronic beryllium disease.  

PubMed

We describe two newly confirmed cases of chronic beryllium disease who presented to our clinic from a facility that only used 2% beryllium copper alloy. These cases illustrate that the 2% beryllium copper alloy continues to cause chronic beryllium disease and that appropriate preventive measures must be taken to control exposures and educate industries and their workers about the hazards of beryllium alloys. PMID:10224597

Balkissoon, R C; Newman, L S

1999-04-01

103

Experience on using titanium as a structural material for a solar neutrino lithium detector  

NASA Astrophysics Data System (ADS)

Data obtained by the radiotracer method on a specially designed test bench show that a lithium oxide film serves as a trap for beryllium extracted from lithium. No tangible chemisorption of beryllium on the titanium surface is observed. These finding are used to design and fabricate a lithium detector for solar neutrinos. They will also find application in designing power nuclear facilities with liquid-metal heat carriers.

Kopylov, A. V.; Orekhov, I. V.; Petukhov, V. V.

2012-04-01

104

Beryllium disease: a clinical perspective  

SciTech Connect

A relatively new occupational disease, beryllium poisoning, is discussed. The history of this respiratory disease among workers after beryllium exposure from extraction and alloy manufacturing is not well documented in the US Attempts by industry to delay investigations into beryllium toxicity are described. The specific incidents occurring at a fluorescent lamp manufacturing plant in Salem, Massachusetts are presented. Clinical observations of chronic beryllium disease are discussed. Symptoms are described. The current status of diagnosis and treatment of beryllium poisoning is presented.

Hardy, H.L.

1980-02-01

105

Comparative Studies of the Electrochemical and Thermal Stability of Composite Electrolytes for Lithium Battery Using Two Types of Boron-based Anion Receptors.  

National Technical Information Service (NTIS)

Comparative studies were done on two new types of boron based anion receptors, tris(pentafluorophenyl) borane (TFPB) and tris(pentafluorophenyl) borate (TFPBO), regarding conductivity enhancement electrochemical and thermal stability when used as additive...

X. Q. Yang H. S. Lee X. Sun J. McBreen

1999-01-01

106

Beryllium Manufacturing Processes  

SciTech Connect

This report is one of a number of reports that will be combined into a handbook on beryllium. Each report covers a specific topic. To-date, the following reports have been published: (1) Consolidation and Grades of Beryllium; (2) Mechanical Properties of Beryllium and the Factors Affecting these Properties; (3) Corrosion and Corrosion Protection of Beryllium; (4) Joining of Beryllium; (5) Atomic, Crystal, Elastic, Thermal, Nuclear, and other Properties of Beryllium; and (6) Beryllium Coating (Deposition) Processes and the Influence of Processing Parameters on Properties and Microstructure. The conventional method of using ingot-cast material is unsuitable for manufacturing a beryllium product. Beryllium is a highly reactive metal with a high melting point, making it susceptible to react with mold-wall materials forming beryllium compounds (BeO, etc.) that become entrapped in the solidified metal. In addition, the grain size is excessively large, being 50 to 100 {micro}m in diameter, while grain sizes of 15 {micro}m or less are required to meet acceptable strength and ductility requirements. Attempts at refining the as-cast-grain size have been unsuccessful. Because of the large grain size and limited slip systems, the casting will invariably crack during a hot-working step, which is an important step in the microstructural-refining process. The high reactivity of beryllium together with its high viscosity (even with substantial superheat) also makes it an unsuitable candidate for precision casting. In order to overcome these problems, alternative methods have been developed for the manufacturing of beryllium. The vast majority of these methods involve the use of beryllium powders. The powders are consolidated under pressure in vacuum at an elevated temperature to produce vacuum hot-pressed (VHP) blocks and vacuum hot-isostatic-pressed (HIP) forms and billets. The blocks (typically cylindrical), which are produced over a wide range of sizes (up to 183 cm dia. by 61 cm high), may be cut or machined into parts or be thermomechanically processed to develop the desired microstructure, properties, and shapes. Vacuum hot-isostatic pressing and cold-isostatic pressing (CIP) followed by sintering and possibly by a final HIP'ing (CIP/Sinter/HIP) are important in their use for the production of near net-shaped parts. For the same starting powder, a HIP'ed product will have less anisotropy than that obtained for a VHP'ed product. A schematic presentation illustrating the difference between VHP'ing and HIP'ing is shown in Figure I-1. The types of powders and the various beryllium grades produced from the consolidated powders and their ambient-temperature mechanical properties were presented in the consolidation report referred to above. Elevated-temperature properties and the effect of processing variables on mechanical properties are described in the mechanical properties report. Beryllium can also be deposited as coatings as well as freestanding forms. The microstructure, properties, and various methods used that are related to the deposition of beryllium are discussed in the report on beryllium coatings.

Goldberg, A

2006-06-30

107

Lithium alloy anode for thermal cells  

SciTech Connect

This patent describes as an article of manufacture, an anode wafer for a thermal cell, the anode wafer comprising particles of a lithium anode alloy bonded with particles of a metal binder, the lithium anode alloy being of the class consisting of lithium-aluminum alloys; lithium-silicon alloys; and lithium-boron alloys, the metal binder being of the class consisting of unalloyed iron, copper, nickel, manganese; and mixtures thereof, and wherein substantially all the metal binder in the wafer remains present as a discrete phase, unalloyed with the lithium alloy.

Cupp, E.B.; Cottingham, D.R.

1986-12-02

108

Control Techniques for Beryllium Air Pollutants.  

National Technical Information Service (NTIS)

Beryllium in almost all forms is known to have adverse effects upon human health. Approximately 300 domestic facilities either extract beryllium or manufacture beryllium-containing products. Beryllium extraction processes generate atmospheric emissions th...

1973-01-01

109

Investigation of Beryllium with Added Dispersoids.  

National Technical Information Service (NTIS)

The research described was undertaken to determine the effect of various nonmetallic and metallic dispersions on the mechanical behavior of beryllium-base composites. The composite systems chosen for study were: beryllium-beryllium oxide, beryllium-beryll...

J. C. Shyne J. W. Moberly O. D. Sherby

1969-01-01

110

Nontraditional Machining of Beryllium.  

National Technical Information Service (NTIS)

The report deals with electrichemical machining (ECM), chemical milling, and electric-discharge machining (EDM). The general characteristics of these processes and their applications to the processing of beryllium parts are presented and covered in detail...

J. A. Gurklis

1972-01-01

111

Bonding in Beryllium Clusters  

NASA Astrophysics Data System (ADS)

Beryllium clusters provide an ideal series for exploring the evolution from discrete molecules to the metallic state. The beryllium dimer has a formal bond order of zero, but the molecule is weakly bound. In contrast, bulk-phase beryllium is a hard metal with a high melting point. Theoretical calculations indicate that the bond energies increase dramatically for Ben clusters in the range n=2-6. A triplet ground state is found for n=6, indicating an early emergence of metallic properties. There is an extensive body of theoretical work on smaller Ben clusters, in part because this light element can be treated using high-level methods. However, the apparent simplicity of beryllium is deceptive, and the calculations have proved to be challenging owing to strong electron correlation and configuration interaction effects. Consequently, these clusters have become benchmark systems for the evaluation of a wide spectrum of quantum chemistry methods.

Heaven, Michael C.; Merritt, Jeremy M.; Bondybey, Vladimir E.

2011-05-01

112

The carcinogenicity of beryllium.  

PubMed Central

Beryllium, some of its alloys, and a variety of its compounds have induced malignant tumors of the lung and osteogenic sarcoma in experimental animals. Three animal species, monkeys, rabbits, and rats, have been shown to be susceptible. Beryllium induces morphological transformation in mammalian cells and enhances viral transformation of mammalian cells. It has been shown to decrease fidelity of DNA synthesis. It has been recognized that exposure to compounds of this metal will, in some individuals, result in a chronic granulomatous disease of the lung. A series of overlapping recent human epidemiological studies have been suggestive of an increase in the incidence of lung cancer in populations occupationally exposed to beryllium. Such studies, together with animal and in vitro studies, argue for the strong presumption of a carcinogenic hazard to man in occupational beryllium exposures.

Kuschner, M

1981-01-01

113

Lattice dynamics of beryllium  

Microsoft Academic Search

Phonon frequencies in beryllium along the principal symmetry directions have been determined by means of the slow neutron\\u000a inelastic scattering technique. The data are analysed in terms of a six-neighbour force constant model and the force constants\\u000a are evaluated. It is concluded that strong tensor forces are present in beryllium and the importance of this finding to basic\\u000a theories of

B A Dasannacharya; P K Iyengar; R V Nandedkar; K R Rao; A P Roy; C L Thaper

1974-01-01

114

Dose of Beryllium Causing Beryllium Sensitization and Disease.  

National Technical Information Service (NTIS)

Chronic beryllium disease (CBD) and beryllum sensitization (BeS) continue to occur in the modem beryllum industry, despite efforts to reduce exposure. This disease is the consequence of a cell-mediated hypersensitivity immune response to beryllium, and ma...

L. S. Newman

2005-01-01

115

Hubble Space Telescope Beryllium Abundances in the alpha Centauri System  

NASA Astrophysics Data System (ADS)

High signal-to-noise ratio Hubble Space Telescope Goddard High-Resolution Spectrograph spectra of alpha Centauri A (spectral type G2 V) and alpha Centauri B (spectral type K1 V) have been analyzed in the Be II lambda 3130 spectral region. Both stars offer an excellent opportunity for testing predictions of 9Be destruction since they are nearby, have a well-determined orbit and parallax, and thus have very well known physical parameters. A detailed spectrum synthesis has been made using a line list that has been carefully tested by comparison with the Sun and with metal-poor stars of different temperature and metallicity. Our analysis gives [Be/H] = +0.06 +/- 0.09 dex for alpha Cen A and -0.54 +/- 0.28 dex for alpha Cen B, using a model atmosphere with a metallicity [M/H] = +0.10. The implications of the new beryllium abundances and the previous lithium studies for models of stellar light-element depletion are then studied. Both the Sun and alpha Cen A are more highly depleted in lithium than younger stars; this is not consistent with standard stellar models. The Sun, alpha Cen A, and alpha Cen B have photospheric 9Be abundances lower than the current accepted solar meteoritic value. Because the initial 9Be abundance for the alpha Cen system is not known, and the depletion is much smaller than that for lithium, it is difficult to determine precise beryllium depletion factors for this system. However, because neither star is expected to deplete beryllium in standard models, the lower relative abundance of alpha Cen B might be evidence for main-sequence beryllium depletion. The theoretical implications of beryllium depletion are briefly discussed.

Primas, F.; Duncan, D. K.; Pinsonneault, M. H.; Deliyannis, Constantine P.; Thorburn, J. A.

1997-05-01

116

Physics and chemistry of beryllium  

Microsoft Academic Search

The combination of properties of beryllium which results in this very low Z element being a candidate for use in fusion reactors is reviewed. The occurrence, availability, and processing of beryllium from both bertrandite (domestic) and beryl (imported) ores are described. The available beryllium grades are characterized. The purity level of these grades, which are all unalloyed in the usual

A. James Stonehouse

1986-01-01

117

High-capacity electrode material BC3 for lithium batteries proposed by ab initio simulations  

NASA Astrophysics Data System (ADS)

The absorption energy and diffusion rates of lithium atoms inside graphitelike boron carbide (BC3) crystal are investigated by the ab initio pseudopotential density-functional method using generalized gradient approximation. It is shown that lithium may effectively intercalate this structure with the maximum lithium concentration corresponding to Li2BC3 stoichiometry, which is threefold in comparison to lithium in graphite. The potential barrier values for lithium diffusion both at low and maximum concentration are about 0.19 eV, so lithium atoms inside the BC3 structure can move easily. These findings suggest that boron carbide looks like a good candidate as an anode material in lithium ion batteries.

Kuzubov, Alexander A.; Fedorov, Aleksandr S.; Eliseeva, Natalya S.; Tomilin, Felix N.; Avramov, Pavel V.; Fedorov, Dmitri G.

2012-05-01

118

Beryllium Uptake by the Common Guppy using Radioisotope 7Be. II. Beryllium Concentration in Fish.  

National Technical Information Service (NTIS)

Two bioassays were conducted in which radioactive beryllium, Be-7, was added as a tracer to beryllium sulfate solutions in order to obtain some insight into beryllium toxicity in fish. Tracer mechanics and procedures for measuring beryllium uptake in gupp...

A. R. Slonim F. C. Dann

1972-01-01

119

Generation of a boron ion beam in a modified ion source for semiconductor applications  

SciTech Connect

Presented here are results of experimental studies on the production of intense beams of boron ions using a modified Bernas-Calutron ion source. Instead of using the conventional boron-trifluoride gas, a solid lithium-boron-tetrafluoride compound was heated to release boron-trifluoride. For optimum ion source parameters the measured 25-41 mA of total ion beam current was composed of 70% singly charged and about 1% doubly charged boron ions.

Gushenets, V.I.; Bugaev, A.S.; Oks, E.M.; Yushkov, G.Yu.; Hershcovitch, Ady; Johnson, B.M.; Kulevoy, T.V.; Poole, H.J.; Swarovsky, A.Ya. [High Current Electronics Institute, Russian Academy of Sciences, Tomsk (Russian Federation); Brookhaven National Laboratory, Upton, New York (United States); Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); PVI, Oxnard, California (United States); A.A. Bochvara Scientific Research Institute for Inorganic Materials, Siberian Branch (Russian Federation)

2006-03-15

120

Parabolic lithium refractive optics for x rays  

Microsoft Academic Search

Excellent x-ray optics for photons at around 10 keV can be expected with lithium metal. One of the best compound refractive lens designs [Lengeler et al., J. Appl. Phys. 84, 5855 (1998)] is now produced routinely in aluminum, and more recently has been demonstrated using beryllium [M. Kuhlmann et al. (unpublished)]. Here, we report a similar refractive lens made from

N. R. Pereira; E. M. Dufresne; R. Clarke; D. A. Arms

2004-01-01

121

EVALUATION OF THE POTENTIAL CARCINOGENICITY OF BERYLLIUM, BERYLLIUM CHLORIDE, BERYLLIUM FLUORIDE, AND BERYLLIUM NITRATE  

EPA Science Inventory

Beryllium is a probable human carcinogen, classified as weight-of-evidence Group B2 under the EPA Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986a). vidence on potential arcinogenicity from animal studies is "Sufficient," and the evidence from human studies is "Inadequa...

122

FORGING BERYLLIUM POWDER  

Microsoft Academic Search

The developments and results obtained in press forging beryllium powder ; are described. The forging method consists of using pressures in the range of ; 20,000 to 100,000 psi, sintering times from l sec to l min, and two temperature ; ranges of l600 and 1900 deg F. The description of a nonberyllium (stainless ; steel) can fabricated for holding

Cieslicki

1962-01-01

123

New electrolytes using Li 2O or Li 2O 2 oxides and tris(pentafluorophenyl) borane as boron based anion receptor for lithium batteries  

Microsoft Academic Search

A new system of electrolytes has been developed and studied for lithium-ion batteries. This new system is based on the interactions between Li2O or Li2O2 and tris(pentafluorophenyl) borane (TPFPB) in carbonate based organic solvents. This opens up a completely new approach in developing non-aqueous electrolytes. In general, the solubility of Li2O or Li2O2 is very low in organic solvents and

B. Xie; H. S. Lee; H. Li; X. Q. Yang; J. McBreen; L. Q. Chen

2008-01-01

124

10 CFR 850.33 - Beryllium emergencies.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Beryllium emergencies. 850.33 Section... DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Specific...Program Requirements § 850.33 Beryllium emergencies. (a) The...

2013-01-01

125

Absorption and diffusion of beryllium in graphite, beryllium carbide formation investigated by density functional theory  

NASA Astrophysics Data System (ADS)

The formation of beryllium carbide from beryllium and graphite is here investigated. Using simple models and density functional theory calculations, a mechanism leading to beryllium carbide is proposed; it would be (i) first diffusion of beryllium in graphite, (ii) formation of a metastable beryllium-intercalated graphitic compound, and (iii) phase transition to beryllium carbide. The growth of beryllium carbide is further controlled by defects' formations and diffusion of beryllium through beryllium carbide. Rate limiting steps are the formation of defects in beryllium carbide, with estimated activation energies close to 2 eV.

Ferro, Yves; Allouche, Alain; Linsmeier, Christian

2013-06-01

126

Cell and defect behavior in lithium-counterdoped solar cells  

SciTech Connect

Some n(+)/p cells in which lithium is introduced as a counterdopant, by ion-implantation, into the cell's boron-doped p-region were studied. To determine if the cells radiation resistance could be significantly improved by lithium counterdoping. Defect behavior was related to cell performance using deep level transient spectroscopy. Results indicate a significantly increased radiation resistance for the lithium counterdoped cells when compared to the boron doped 1 ohm-cm control cell. The increased radiation resistance of the lithium counterdoped cells is due to the complexing of lithium with divacancies and boron. It is speculated that complexing with oxygen and single vacancies also contributes to the increased radiation resistance. Counterdoping silicon with lithium results in a different set of defects.

Weinberg, I.; Mehta, S.

1984-01-01

127

Neutron damage in beryllium  

NASA Astrophysics Data System (ADS)

The effects of neutron irradiation on the mechanical properties and helium retention of beryllium are being studied using postirradiation tensile testing, fractography, and microstructural examinations on arc cast beryllium that was irradiated in the FFTF/MOTA to support the International Thermonuclear Experimental Reactor (ITER) design effort. Miniature sheet tensile specimens were embrittled by irradiation at 400C to 8 displacements per atom (dpa). Failure with zero ductility occurs with both transgranular brittle cleavage and grain boundary embrittlement. Based on microstructural examination, embrittlement is ascribed both to helium bubble formation at grain boundaries and to c-type loop formation. Loop formation of this type has rarely been reported in the literature. Companion microstructural examination specimens of identical material were irradiated at 500C to 1 dpa. The major effect of irradiation at 500C is the development of helium bubbles on matrix and grain boundary dislocations, but evidence of the onset of void swelling was also found.

Gelles, D. S.; Heinisch, H. L.

1992-09-01

128

Liquid lithium self-cooled breeding blanket design for ITER  

Microsoft Academic Search

To meet the technical objectives of the ITER extended performance phase (EPP) an advanced tritium breeding lithium\\/vanadium (Li\\/V) blanket was developed by two home teams (US and RF). The design is based on the use of liquid Li as coolant and breeder and vanadium alloy (V-Cr-Ti) as structural material. The first wall is coated with a beryllium protection layer. Beryllium

I. R Kirillov; I. V Danilov; S. I Sidorenkov; Yu. S Strebkov; R. F Mattas; Y Gohar; T. Q Hua; D. L Smith

1998-01-01

129

Characterization of shocked beryllium  

NASA Astrophysics Data System (ADS)

While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. In the current work, high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. Two constitutive strength (plasticity) models, the Preston-Tonks-Wallace (PTW) and Mechanical Threshold Stress (MTS) models, were calibrated using common quasi-static and Hopkinson bar data. However, simulations with the two models give noticeably different results when compared with the measured experimental wave profiles. The experimental results indicate that, even if fractured by the initial shock loading, the Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading. Additional "arrested" drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

Cady, C. M.; Adams, C. D.; Hull, L. M.; Gray, G. T.; Prime, M. B.; Addessio, F. L.; Wynn, T. A.; Papin, P. A.; Brown, E. N.

2012-08-01

130

Machining of beryllium with the LLNL Precision Engineering Research Lathe  

SciTech Connect

In August 1984, six flat samples of beryllium, which were prepared by Brush-Wellmen Corp. using various pressing and sintering processes, were machined at LLNL on the recently completed Precision Engineering Research Lathe (PERL). The purpose of this study, which was conducted in cooperation with the Hughes Aircraft Corporation and partially funded by that organization, was to determine the optical properties of machined beryllium surfaces when prepared under highly controlled conditions using high quality machine tools and CBN (cubic boron nitrite) cutting tools. This report will summarize the materials properties, the machining conditions used on the PERL and a comparison of the completed samples using optical measuring techniques and scanning electron microscopy (SEM). The mirror surface reflecting measurements in the IR region are to be made by the group at Hughes Aircraft and will be exchanged with LLNL as a part of this joint technical effort. 3 refs., 14 figs.

Foley, R.J.

1985-04-01

131

5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING BEGAN IN SIDE A OF THE BUILDING IN 1962. (11/5/73) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

132

Characterization of Shocked Beryllium  

SciTech Connect

Beryllium metal has many excellent structural properties in addition to its unique radiation characteristics, including: high elastic modulus, low Poisson's ratio, low density, and high melting point. However, it suffers from several major mechanical drawbacks: 1) high anisotropy - due to its hexagonal lattice structure and its susceptibility to crystallographic texturing; 2) susceptibility to impurity-induced fracture - due to grain boundary segregation; and 3) low intrinsic ductility at ambient temperatures thereby limiting fabricability. While large ductility results from deformation under the conditions of compression, the material can exhibit a brittle behavior under tension. Furthermore, there is a brittle to ductile transition at approximately 200 C under tensile conditions. While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. The beryllium used in this study was Grade S200-F (Brush Wellman, Inc., Elmore, OH) material. The work focused on high strain rate deformation and examine the validity of constitutive models in deformation rate regimes, including shock, the experiments were modeled using a Lagrangian hydrocode. Two constitutive strength (plasticity) models, the Preston-Tonks-Wallace (PTW) and Mechanical Threshold Stress (MTS) models, were calibrated using the same set of quasi-static and Hopkinson bar data taken at temperatures from 77K to 873K and strain rates from 0.001/sec to 4300/sec. In spite of being calibrated on the same data, the two models give noticeably different results when compared with the measured wave profiles. These high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Preliminary analysis of the results appears to indicate that, if fractured by the initial shock loading, the S200F Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading of the material. Additional 'arrested' drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

Cady, Carl M [Los Alamos National Laboratory; Adams, Chris D [Los Alamos National Laboratory; Hull, Lawrence M [Los Alamos National Laboratory; Gray III, George T [Los Alamos National Laboratory; Prime, Michael B [Los Alamos National Laboratory; Addessio, Francis L [Los Alamos National Laboratory; Wynn, Thomas A [Los Alamos National Laboratory; Brown, Eric N [Los Alamos National Laboratory

2012-08-24

133

Beryllium Copper in Instrument Design  

Microsoft Academic Search

The physical characteristics of beryllium copper are described with particular reference to elastic properties. The usefulness of this alloy for instrument springs and similar parts is shown to be in its combination of high elastic limit with relatively low elastic modulus. The bearing of these and of other properties of beryllium copper upon the problems of arriving at appropriate deflexions

L B Hunt

1944-01-01

134

Sintered beryllium-base compositions  

Microsoft Academic Search

1.The low corrosion resistance of beryllium in humid gaseous atmospheres is mainly due to hydrogen absorption. The harmful influence of hydrogen on the protective properties of oxide films may be significantly reduced by employing measures for removing hydrogen from materials or by initially establishing an impervious oxide film on the surface.2.Sintered beryllium prepared from preoxidized powders exhibits high corrosion resistance

V. E. Ivanov; V. F. Zelenskii; V. K. Khorenko; B. V. Matvienko; L. A. Kornienko

1968-01-01

135

Method for fabricating beryllium structures  

DOEpatents

Thin-walled beryllium structures are prepared by plasma spraying a mixture of beryllium powder and about 2500 to 4000 ppm silicon powder onto a suitable substrate, removing the plasma-sprayed body from the substrate and placing it in a sizing die having a coefficient of thermal expansion similar to that of the beryllium, exposing the plasma-sprayed body to a moist atmosphere, outgassing the plasma-sprayed body, and then sintering the plasma-sprayed body in an inert atmosphere to form a dense, low-porosity beryllium structure of the desired thin-wall configuration. The addition of the silicon and the exposure of the plasma-sprayed body to the moist atmosphere greatly facilitate the preparation of the beryllium structure while minimizing the heretofore deleterious problems due to grain growth and grain orientation.

Hovis, Jr., Victor M. (Kingston, TN); Northcutt, Jr., Walter G. (Oak Ridge, TN)

1977-01-01

136

[Immunotoxicity of beryllium].  

PubMed

The lymphocyte transformation test and the macrophage migration inhibition test are quantitative methods invaluable for examination of beryllium (hereafter referred to as Be) effects on cell-mediated immunity. We recognized that the Be sensitizing ability was related to active as well as passive cell-mediated immunity in mice subcutaneously injected with Be once a week over a 6-week period. Be also affects B cells, and it increases the amount of immunoglobulins in sera. In the study of immunological health surveys of Be workers in a copper-beryllium casting factory, the serum complement titer tended to be lower in Be workers than in the controls. In mice, injected with Be once a week over a 12-week period, serum complement titers decreased. Correlation coefficients of the experimental parameters showed a significant negative correlation between the complement titers and the prothrombin time or the coagulation time for factor VII, using mice injected with 5 micrograms of Be. It was suggested that increases in the complement titers after Be administration may be induced by temporarily-activated plasma serin protease, which is a component of blood coagulation factor VII. The delta-aminolevulinic acid dehydratase and porphobilinogen deaminase activities were significantly elevated in the pregnant untreated group, compared with the nonpregnant mice (the control group). However, it was noted that these values in the pregnant mice injected with 50 micrograms of Be were almost the same as the values of the controls. It suggests that Be suppressed the expected pregnancy-induced increase in hematopoietic function. There are at least two risk factors induced in the effects of beryllium on organisms-exposure to the metal and inheritance of the genetic marker. It is necessary to reduce exposure, to give preventive education and to carry out periodic health examinations for the prevention of disease induced by Be. PMID:9528258

Sakaguchi, T; Sakaguchi, S; Kudo, Y

1998-01-01

137

The INEL beryllium multiplication experiment  

SciTech Connect

The experiment to measure the multiplication of 14-MeV neutrons in bulk beryllium has been completed. The experiment consists of determining the ratio of {sup 56}Mn activities induced in a large manganese bath by a central 14-MeV neutron source, with and without a beryllium sample surrounding the source. In the manganese bath method a neutron source is placed at the center of a totally-absorbing aqueous solution of MnSo{sub 4}. The capture of neutrons by Mn produces a {sup 56}Mn activity proportional to the emission rate of the source. As applied to the measurement of the multiplication of 14- MeV neutrons in bulk beryllium, the neutron source is a tritium target placed at the end of the drift tube of a small deuteron accelerator. Surrounding the source is a sample chamber. When the sample chamber is empty, the neutrons go directly to the surrounding MnSO{sub 4} solution, and produce a {sup 56}Mn activity proportional to the neutron emission rate. When the chamber contains a beryllium sample, the neutrons first enter the beryllium and multiply through the (n,2n) process. Neutrons escaping from the beryllium enter the bath and produce a {sup 56}Mn activity proportional to the neutron emission rate multiplied by the effective value of the multiplication in bulk beryllium. The ratio of the activities with and without the sample present is proportional to the multiplication value. Detailed calculations of the multiplication and all the systematic effects were made with the Monte Carlo program MCNP, utilizing both the Young and Stewart and the ENDF/B-VI evaluations for beryllium. Both data sets produce multiplication values that are in excellent agreement with the measurements for both raw and corrected values of the multiplication. We conclude that there is not real discrepancy between experimental and calculated values for the multiplication of neutrons in bulk beryllium. 12 figs., 11 tabs., 18 refs.

Smith, J.R.; King, J.J.

1991-03-01

138

The natural history of beryllium sensitization and chronic beryllium disease  

SciTech Connect

With the advent of in vitro immunologic testing, we can now detect exposed individuals who are sensitized to beryllium and those who have chronic beryllium disease (CBD) with lung pathology and impairment. Earlier detection and more accurate diagnostic tools raise new questions about the natural history of sensitization and granulomatous disease. Preliminary data suggest that early detection identifies people who are sensitized to beryllium and that these individuals are at risk for progressing into clinical disease. This article discusses the historical, recent, and ongoing studies germane to our understanding of CBD natural history, including the immunologic and inflammatory basis of the disease, the environmental and host risk factors for disease progression, biological markers of disease severity and activity that may help predict outcome, and the implications for broad-based workplace screening to identify patients at the earliest stages of beryllium sensitization and disease. 29 refs., 2 figs.

Newman, L.S. [National Jewish Center for Immunology and Respiratory Medicine, Denver, CO (United States)]|[Univ. of Colorado, Denver, CO (United States); Lloyd, J.; Daniloff, E. [National Jewish Center for Immunology and Respiratory Medicine, Denver, CO (United States)

1996-10-01

139

Beryllium 10\\/beryllium 7 as a tracer of stratospheric transport  

Microsoft Academic Search

We use the ratio between cosmogenic radionuclides beryllium 10 (t1\\/2=1.5106 years) and beryllium 7 (t1\\/2=53 days) to study stratospheric transport, particularly the exchange between the tropics and the high latitudes and as an indicator of stratosphere-troposphere exchange. Both tracers are generated steadily, with maximum production occurring at midlatitudes of the stratosphere. During transport away from their source the ratio 10Be\\/7Be

Dorothy Koch; David Rind

1998-01-01

140

Beryllium technology workshop, Clearwater Beach, Florida, November 20, 1991.  

National Technical Information Service (NTIS)

This report discusses the following topics: beryllium in the ITER blanket; mechanical testing of irradiated beryllium; tritium release measurements on irradiated beryllium; beryllium needs for plasma-facing components; thermal conductivity of plasma spray...

G. R. Longhurst

1991-01-01

141

Beryllium Interactions in Molten Salts  

SciTech Connect

Molten flibe (2LiFBeF2) is a candidate as a cooling and tritium breeding media for future fusion power plants. Neutron interactions with the salt will produce tritium and release excess free fluorine ions. Beryllium metal has been demonstrated as an effective redox control agent to prevent free fluorine, or HF species, from reacting with structural metal components. The extent and rate of beryllium solubility in a pot design experiments to suppress continuously supplied hydrogen fluoride gas has been measured and modeled[ ]. This paper presents evidence of beryllium loss from specimens, a dependence of the loss upon bi-metal coupling, i.e., galvanic effect, and the partitioning of the beryllium to the salt and container materials. Various posttest investigative methods, viz., scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) were used to explore this behavior.

G. S. Smolik; M. F. Simpson; P. J. Pinhero; M. Hara; Y. Hatano; R. A. Anderl; J. P. Sharpe; T. Terai; S. Tanaka; D. A. Petti; D.-K. Sze

2006-01-01

142

The Challenge of Beryllium Observations  

NASA Astrophysics Data System (ADS)

Stars of a wide range of metallicity have been observed and analyzed in the spectral region of the Be II resonant doublet (~3130A), from the most metal-poor ones, which give us information on the primary mechanism(s) of Be production during the early phases of galactic evolution, to solar-type stars, which become fundamental tools to investigate the structure of the outermost layers of their atmospheres and to constrain which mixing and depletion mechanisms are more effective. We tested the different theoretical scenarios proposed so far to explain the formation of beryllium, namely if the classical cosmic-ray theory of spallation of interstellar CNO atoms by colliding protons and alpha-particles, proposed 25 years ago by Reeves et al. (1970, Nature, 226, 727), remains a valid explanation, or if the most recent suggestions of a reversed mechanism, involving spallation between H and He interstellar atoms hit by accelerated CNO nuclei in the vicinity of supernovae (Duncan et al. 1992, ApJ, 401, 584; Casse et al. 1995, Nature, 373, 318), may better account for what we observe today. A reduced chi^2 analysis has shown a correlation of [Be/H] with [Fe/H] characterized by a slope of 0.82, that suggests a behaviour more akin to that of a primary element rather than a secondary one. This strongly favors the most recent view of creation of Be (and B) through spallation by CNO nuclei accelerated during a supernova explosion which gives the best reproduction of our set of abundances, although it needs to be tested with larger samples of data for both beryllium and boron abudances. Our findings of a linear trend between [Be/H] and [Fe/H], of slope 0.82 +/- 0.24 (1-sigma), and of a real dispersion among different objects at almost the same metallicity can be considered the most important result of this analysis. The observed scatter might suggest the onset of some different mechanism involved in the galactic production of beryllium, additional destruction mechanisms, or, in the most recent scenario of Be formation, it might also reflect the presence of inhomogeneities in the interstellar medium surrounding active star forming regions. There is no suggestion of a break at the metallicity of [M/H]= -1.00 that usually marks the transition between halo and disk stars, although a larger homogeneous sample of observations could test this better. No other change of slope seems necessary to fit satisfactorily our observed trend in the logarithmic plane [Be/H] vs. [Fe/H], as previously suggested by other investigations. There is no plateau at the lowest metallicities which might indicate a primordial contribution to Be production. Two of the most metal-poor stars we analyzed are subgiants, with effective temperatures Three stars have no detectable Be absorption, which seems to indicate that their Be content has been depleted, thus becoming useful data points in testing predictions of depth of mixing in stellar structure models. They increase the small number of objects already found with strong Be depletion, and along with the few halo stars which are Li-poor, suggest that their anomalies should be further tested by analysing their B abundances. Analysis of HST (Hubble Space Telescope) spectra of both components A and B of the Alpha Centauri system yields a solar Be abundance in alfa Cen A and [Be/H]= -0.50 dex in alfa Cen B. The lack of Be destruction in component A and moderate destruction in B has allowed a rather accurate determination of the depth of mixing, to a temperature intermediate between 2.5 and 3.5 X 10^6 K in the case of alfa Cen A, and to very close to 3 X 10^6 K in the case of alfa Cen B (Primas et al. 1996, in preparation). (SECTION: Dissertation Summaries)

Primas, Francesca

1996-08-01

143

Saturation with beryllium by diffusion  

Microsoft Academic Search

1.We proposed a method of diffusional saturation with powders, using metallic magnesium to create an oxidation-free atmosphere in the furnace and to activate the surface of the metal and the powder saturated with beryllium. Metallic magnesium can be used for diffusional saturation with other elements.2.Beryllium saturated layers have a high hardness.3.Diffusional layers on technical iron, the ZhS6-K alloy, and molybdenum

G. V. Zemskov; P. I. Mel'nik

1966-01-01

144

Lithium counterdoped silicon solar cell  

SciTech Connect

A radiation damage resistant solar cell is described comprising a wafer of p-type boron doped silicon having lithium ions implanted therein in small enough quantities such that the wafer remains p-type after lithium addition. The wafer has an n/sup +/ region formed by phosphorus ions implanted therein adjacent to a surface of the wafer, a first electrical contact on the surface adjacent to the n/sup +/ region, and a second electrical contact on an opposite surface of the wafer.

Weinberg, I.; Brandhorst, H.W. Jr.

1986-08-26

145

Neutron multiplication in beryllium  

SciTech Connect

Integral neutron multiplication experiments have been performed using spherical shells of beryllium metal of 4.6-, 6.99-, 7.87-, 9.38-, 13.8-, and 19.9-cm thickness. Neutron leakage, from {sup 252}Cf and a DT neutron source normalized with an associated particle detector, were measured with a Bonner sphere spectrometer system. The neutron fluence was obtained by processing the room-returned and air-scattered corrected count-rate data with a Bonner sphere spectrum unfolding routine and a weighted Bonner sphere technique. The neutron multiplication was obtained directly by comparing the normalized neutron leakage fluence with and without beryllium present. The neutron leakage spectra were calculated for each shell using the discrete ordinates codes ANISN and ONEDANT with ENDF/B-IV and ENDF/B-V respectively. The cross sections from ENDF/B-V included the most current cross section revisions from the Los Alamos National Laboratory. A comparison of the leakage multiplication, calculated using the two versions of evaluated nuclear data, indicate that corrections have been made to the energy-angle distribution of the secondary neutrons in ENDF/B-V resulting in a lower neutron leakage multiplication for shells greater than 9.38-cm thickness. The measured {sup 252}Cf neutron leakage multiplication is 22% higher than the ANISN-ENDF/B-IV calculated leakage multiplication for the 4.6-cm shell thickness, within 4% for the 6.99-cm thickness, and at least 29% lower than the calculated leakage multiplication for the 19.9-cm shell thickness.

Hartley, R.S.

1987-01-01

146

Boron alloy  

SciTech Connect

This paper describes a ferro-boron alloy produced in situ in a basic oxygen furnace, an induction furnace, or an electric furnace, or in combination with a mixing vessel. It comprises: 1.4% to 15% by weight boron; less than 0.002% by weight nitrogen; less than about 0.2% by weight carbon; less than about 0.01% by weight aluminum; and the balance iron with minute amounts of residuals.

Sussman, R.C.; Evans, L.G.

1990-06-26

147

Extraction of Beryllium from Refractory Beryllium Oxide with Dilute Ammonium Bifluoride and Determination by Fluorescence: A Multiparameter Performance Evaluation  

Microsoft Academic Search

Beryllium exposure can cause a number of deleterious health effects, including beryllium sensitization and the potentially fatal chronic beryllium disease. Efficient methods for monitoring beryllium contamination in workplaces are valuable to help prevent dangerous exposures to this element. In this work, performance data on the extraction of beryllium from various size fractions of high-fired beryllium oxide (BeO) particles (from <

Michael J. Goldcamp; Diane M. Goldcamp; Kevin Ashley; Joseph E. Fernback; Anoop Agrawal; Mark Millson; David Marlow; Kenneth Harrison

2009-01-01

148

Characterization of physicochemical properties of beryllium aerosols associated with prevalence of chronic beryllium disease  

Microsoft Academic Search

Little is known about the physicochemical properties of beryllium aerosols associated with increased risk of beryllium sensitization and chronic beryllium disease (CBD). Such information is needed to evaluate whether airborne mass of beryllium is the appropriate metric of exposure or alternatively to provide a scientific basis for using information on particle size, surface area, and chemistry to support an improved

Aleksandr B. Stefaniak; Mark D. Hoover; Gregory A. Day; Robert M. Dickerson; Eric J. Peterson; Michael S. Kent; Christine R. Schuler; Patrick N. Breysseb; Ronald C. Scripsick

2004-01-01

149

Layered carbon lattices and their influence on the nature of lithium bonding in lithium intercalated carbon anodes.  

SciTech Connect

Ab initio molecular orbital calculations have been used to investigate the nature of lithium bonding in stage 1 lithium intercalated carbon anodes. This has been approximated by using layered carbon lattices such as coronene, (C{sub 24}H{sub 12}),anthracene, and anthracene substituted with boron. With two coronene carbon lattices forming a sandwich structure and intercalated with either 2, 3, 4 or 6 six lithiums, it has been found that the predominant mode of bonding for the lithium is at the carbon edge sites as opposed to bonding at interior carbon hexagon sites. Formation of all structures is thermodynamically allowed except for the two lithium case in which there is repulsion between the lattices. The optimized structure with six lithiums gives a reasonable approximation for the stage 1 lithium intercalated carbon anode. In this case the lithium to carbon ratio is 1:8 versus 1:6 occurring in the stage 1 graphite. The coronene lattices are eclipsed with a separation of 4.03 {angstrom}. However, there is a slight ruffling of the lattice. Separation between adjacent lithiums is either 3.32 {angstrom} or 2.98 {angstrom}. Even though the separation between lithiums is very small, composition of the molecular orbitals suggests that there is no lithium cluster formation. The highest occupied molecular orbitals are composed of a combination of lithium and carbon orbitals. In contrast, in the C{sub 60} fullerene lattice with three and five lithiums intercalated, there are molecular orbitals composed only of lithiums, indicative of cluster formation. For anthracene and boron substituted anthracene, lithium bonding takes place within the carbon hexagon sites. The separation between lithiums in a sandwich type structure with two anthracenes in the eclipsed conformation is 5.36 {angstrom}. The effect of boron in a carbon lattice has been evaluated by comparing the difference in behavior of a single anthracene lattice reacting with a dilithium cluster as compared to a 1, 4, 5, 8-tetraboroanthracene lattice. The effect of boron substitution is to increases lattice flexibility by allowing the lattice to twist and lithium to bond at adjacent hexagon sites. The thermodynamic feasibility of the reaction between the dilithium cluster and the boron substituted anthracene lattice is enhanced.

Scanlon, L.G.

1998-05-27

150

NIFTI and DISCOS: New concepts for a compact accelerator neutron source for boron neutron capture therapy applications  

SciTech Connect

Two new concepts, NIFTI and DISCOS, are described. These concepts enable the efficient production of epithermal neutrons for BNCT (Boron Neutron Capture Therapy) medical treatment, utilizing a low current, low energy proton beam impacting on a lithium target. The NIFTI concept uses fluoride compounds, such as lead or beryllium fluoride, to efficiently degrade high energy neutrons from the lithium target to the lower energies required for BNCT. The fluoride compounds are in turn encased in an iron layer that strongly impedes the transmission of neutrons with energies above 24 KeV. Lower energy neutrons readily pass through this iron filter, which has a deep window in its scattering cross section at 24 KeV. The DISCOS concept uses a rapidly rotating, high g disc to create a series of thin ({approximately} 1 micron thickness) liquid lithium targets in the form of continuous films or sheets of discrete droplets--through which the proton beam passes. The average energy lost by a proton as it passes through a single target is small, approximately 10 KeV. Between the targets, the proton beam is re-accelerated by an applied DC electric field. The DISCOS approach enables the accelerator--target facility to operate with a beam energy only slightly above the threshold value for neutron production--resulting in an output beam of low-energy epithermal neutrons--while achieving a high yield of neutrons per milliamp of proton beam current. Parametric trade studies of the NIFTI and DISCOS concepts are described. These include analyses of a broad range of NIFTI designs using the Monte carlo MCNP neutronics code, as well as mechanical and thermal-hydraulic analyses of various DISCOS designs.

Powell, J.; Ludewig, H.; Todosow, M.; Reich, M. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology

1995-06-01

151

Defense programs beryllium good practice guide.  

National Technical Information Service (NTIS)

Within the DOE, it has recently become apparent that some contractor employees who have worked (or are currently working) with and around beryllium have developed chronic beryllium disease (CBD), an occupational granulomatous lung disorder. Respiratory ex...

M. Herr

1997-01-01

152

Minerals yearbook, 1990: Beryllium. Annual report  

Microsoft Academic Search

The United States is the only market economy country with an integrated beryllium industry. Bertrandite, mined and processed in Utah, is the primary mineral source for the end products--beryllium metal, beryllium alloys, and beryllium oxide--that are produced in Ohio and Pennsylvania. Imported beryl, mainly from Brazil, supplements domestic mineral supply. In 1990, U.S. mine production declined slightly, continuing a 3-year

1990-01-01

153

Process-related risk of beryllium sensitization and disease in a copper-beryllium alloy facility  

Microsoft Academic Search

Background Chronic beryllium disease (CBD), which primarily affects the lungs, occurs in sensitized beryllium-exposed individuals. At a copper-beryllium alloy strip and wire finishing facility we performed a cross-sectional survey to examine prevalences of beryllium sensitization and CBD, and relationships between sensitization and CBD and work areas\\/processes. Methods Current employees (185) were offered beryllium lymphocyte proliferation testing (BeLPT) for sensitization, clinical

Christine R. Schuler; Michael S. Kent; David C. Deubner; Michael T. Berakis; Michael McCawley; Paul K. Henneberger; Milton D. Rossman; Kathleen Kreiss

2005-01-01

154

METHOD FOR PREPARATION OF SINTERABLE BERYLLIUM OXIDE  

DOEpatents

High-purity beryllium oxide for nuclear reactor applications can be prepared by precipitation of beryllium oxalate monohydrate from aqueous solution at a temperature above 50 deg C and subsequent calcination of the precipitate. Improved purification with respect to metallic impurities is obtained, and the product beryllium oxide sinters reproducibly to a high density. (AEC)

Sturm, B.J.

1963-08-13

155

Beryllium in the Environment: A Review  

Microsoft Academic Search

Beryllium is an important industrial metal because of its unusual material properties: it is lighter than aluminum and six times stronger than steel. Often alloyed with other metals such as copper, beryllium is a key component of materials used in the aerospace and electronics industries. Beryllium has a small neutron cross-section, which makes it useful in the production of nuclear

Tammy P. Taylor; Mei Ding; Deborah S. Ehler; Trudi M. Foreman; John P. Kaszuba; Nancy N. Sauer

2003-01-01

156

Beryllium--important for national defense  

USGS Publications Warehouse

Beryllium is one of the lightest and stiffest metals, but there was little industrial demand for it until the 1930s and 1940s when the aerospace, defense, and nuclear sectors began using beryllium and its compounds. Beryllium is now classified by the U.S. Department of Defense as a strategic and critical material because it is used in products that are vital to national security. The oxide form of beryllium was identified in 1797, and scientists first isolated metallic beryllium in 1828. The United States is the world's leading source of beryllium. A single mine at Spor Mountain, Utah, produced more than 85 percent of the beryllium mined worldwide in 2010. China produced most of the remainder, and less than 2 percent came from Mozambique and other countries. National stockpiles also provide significant amounts of beryllium for processing. To help predict where future beryllium supplies might be located, U.S.Geological Survey (USGS) scientists study how and where beryllium resources are concentrated in Earth's crust and use that knowledge to assess the likelihood that undiscovered beryllium resources may exist. Techniques to assess mineral resources have been developed by the USGS to support the stewardship of Federal lands and to better evaluate mineral resource availability in a global context. The USGS also compiles statistics and information on the worldwide supply of, demand for, and flow of beryllium. These data are used to inform U.S. national policymaking.

Boland, M. A.

2012-01-01

157

Processing Irradiated Beryllium For Disposal  

SciTech Connect

The purpose of this research was to develop a process for decontaminating irradiated beryllium that will allow it to be disposed of through normal radwaste channels. Thus, the primary objectives of this ongoing study are to remove the transuranic (TRU) isotopes to less than 100 nCi/g and remove {sup 60}Co, and {sup 137}Cs, to levels that will allow the beryllium to be contact handled. One possible approach that appears to have the most promise is aqueous dissolution and separation of the isotopes by selected solvent extraction followed by precipitation, resulting in a granular form for the beryllium that may be fixed to prevent it from becoming respirable and therefore hazardous. Beryllium metal was dissolved in nitric and fluorboric acids. Isotopes of {sup 241}Am, {sup 239}Pu, {sup 85}Sr, and {sup 137}Cs were then added to make a surrogate beryllium waste solution. A series of batch contacts was performed with the spiked simulant using chlorinated cobalt dicarbollide (CCD) and polyethylene glycol diluted with sulfone to extract the isotopes of Cs and Sr. Another series of batch contacts was performed using a combination of octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in tributyl phosphate (TBP) diluted with dodecane for extracting the isotopes of Pu and Am. The results indicate that greater than 99.9% removal can be achieved for each isotope with only three contact stages.

T. J. Tranter; R. D. Tillotson; N. R. Mann; G. R. Longhurst

2005-11-01

158

Beryllium Related Matter  

SciTech Connect

In recent months, LLNL has identified, commenced, and implemented a series of interim controls, compensatory measures, and initiatives to ensure worker safety, and improve safety processes with regards to potential worker exposure to beryllium. Many of these actions have been undertaken in response to the NNSA Independent Review (COR-TS-5/15/2008-8550) received by LLNL in November of 2008. Others are the result of recent discoveries, events or incidents, and lessons learned, or were scheduled corrective actions from earlier commitments. Many of these actions are very recent in nature, or are still in progress, and vary in the formality of implementation. Actions are being reviewed for effectiveness as they progress. The documentation of implementation, and review of effectiveness, when appropriate, of these actions will be addressed as part of the formal Corrective Action Plan addressing the Independent Review. The mitigating actions taken fall into the following categories: (1) Responses to specific events/concerns; (2) Development of interim controls; (3) Review of ongoing activities; and (4) Performance improvement measures.

Gaylord, R F

2008-12-23

159

Beryllium Abundances in Solar Mass Stars  

NASA Astrophysics Data System (ADS)

Light element abundance analysis allows for a deeper understanding of the chemical composition of a star beneath its surface. Beryllium provides a probe down to 3.5106 K, where it fuses with protons. In this study, Be abundances were determined for 52 F and G dwarfs selected from a sample of local thin disc stars. These stars were selected by mass to range from 0.9 to 1.1 M?. They have effective temperatures from 5600 to 6400 K, and their metallicities [Fe/H]=-0.65 to +0.11. The data were taken with the Keck HIRES instrument and the Gecko spectrograph on the Canada France Hawaii Telescope. The abundances were calculated via spectral synthesis and were analyzed to investigate the Be abundance as a function of age, temperature, metallicity, and its relation to the lithium abundance for this narrow mass range. Be is found to decrease linearly with metallicity down to [Fe/H]-4.0 with slope 0.86 0.02. The relation of the Be abundance to effective temperature is dependent upon metallicity, but when metallicity effects are taken into account, there is a spread 1.2 dex. We find a 1.5 dex spread in A(Be) when plotted against age, with the largest spread occurring from 6-8 Gyr. The relation with Li is found to be linear with slope 0.36 0.06 for the temperature regime of 5900-6300 K.

Krugler, J. A.; Boesgaard, A. M.

2008-08-01

160

Minerals yearbook, 1990: Beryllium. Annual report  

SciTech Connect

The United States is the only market economy country with an integrated beryllium industry. Bertrandite, mined and processed in Utah, is the primary mineral source for the end products--beryllium metal, beryllium alloys, and beryllium oxide--that are produced in Ohio and Pennsylvania. Imported beryl, mainly from Brazil, supplements domestic mineral supply. In 1990, U.S. mine production declined slightly, continuing a 3-year trend. Persistent weak demand in the automotive, defense, and telecommunications markets led to a decline in usage of beryllium metal, alloys, and oxide. But the U.S. mine production supplied a greater percentage of the domestic demand, while beryl imports continued to decrease.

Kramer, D.A.

1990-01-01

161

Cause of pitting in beryllium  

SciTech Connect

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of the pattern is attributed to these voids and etching out of fines and associated impurities. Hot isostatic pressing with a subsequent heat treatment close residual porosity and dispersed impurities enough to correct the problem.

Kershaw, R.P.

1982-04-16

162

Amorphous boron gasket in diamond anvil cell research  

Microsoft Academic Search

Recent advances in high-pressure diamond anvil cell experiments include high-energy synchrotron x-ray techniques as well as new cell designs and gasketing procedures. The success of high-pressure experiments usually depends on a well-prepared sample, in which the gasket plays an important role. Various gasket materials such as diamond, beryllium, rhenium, and stainless steel have been used. Here we introduce amorphous boron

Jung-Fu Lin; Jinfu Shu; Ho-Kwang Mao; Russell J. Hemley; Guoyin Shen

2003-01-01

163

A Critical Assessment of Boron Neutron Capture Therapy: An Overview  

Microsoft Academic Search

Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when boron-10 is irradiated with neutrons of the appropriate energy to produce high-energy alpha particles and recoiling lithium-7 nuclei. BNCT has been used clinically to treat patients with high-grade gliomas, and a much smaller number with primary and metastatic melanoma. The purpose of this special issue of

Rolf F. Barth

2003-01-01

164

A critical assessment of boron neutron capture therapy: an overview  

Microsoft Academic Search

SummaryBoron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when boron-10 is irradiated with neutrons\\u000a of the appropriate energy to produce high-energy alpha particles and recoiling lithium-7 nuclei. BNCT has been used clinically\\u000a to treat patients with high-grade gliomas, and a much smaller number with primary and metastatic melanoma. The purpose of\\u000a this special issue of

Rolf F. Barth

2003-01-01

165

Development of Beryllium Alloys for High Strength Beryllium Wires.  

National Technical Information Service (NTIS)

Results of a program designed to produce 5 mil dia. beryllium wire of strength near 300,000 psi are described. It consisted of drawing wire from two starting materials, powder of a thermally reduced origin and powder of an electrorefined origin. Various h...

J. N. Hurd R. G. O'Rourke R. J. Lohrer

1970-01-01

166

Effects of lithium counterdoping on radiation damage and annealing in N + P silicon solar cells  

SciTech Connect

Boron doped silicon solar cells were counterdoped with lithium by ion implantation and the resultant cells irradiated by one million electronvolt electrons. The lithium counterdoped cells exhibited increased radiation resistance when compared to boron doped control cells. Significant annealing occurred at 100/sup 0/C. It was speculated that the increased radiation resistance of the counterdoped cells is due to the interaction of lithium with oxygen, single and double vacancies, and that the lithium-oxygen interaction is the major contributor to the increased radiation resistance.

Brandhorst, H.W. Jr.; Mehta, S.; Swartz, C.K.

1984-09-01

167

Boron Neutron Capture Therapy (BNCT) Dose Calculation using Geometrical Factors Spherical Interface for Glioblastoma Multiforme  

SciTech Connect

Boron Neutron Capture Therapy (BNCT) is a cancer therapy by utilizing thermal neutron to produce alpha particles and lithium nuclei. The superiority of BNCT is that the radiation effects could be limited only for the tumor cells. BNCT radiation dose depends on the distribution of boron in the tumor. Absorbed dose to the cells from the reaction 10B (n, {alpha}) 7Li was calculated near interface medium containing boron and boron-free region. The method considers the contribution of the alpha particle and recoiled lithium particle to the absorbed dose and the variation of Linear Energy Transfer (LET) charged particles energy. Geometrical factor data of boron distribution for the spherical surface is used to calculate the energy absorbed in the tumor cells, brain and scalp for case Glioblastoma Multiforme. The result shows that the optimal dose in tumor is obtained for boron concentrations of 22.1 mg {sup 10}B/g blood.

Zasneda, Sabriani; Widita, Rena [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10 Bandung, 40132 (Indonesia)

2010-06-22

168

Why boron?  

Microsoft Academic Search

It is now more than 80years since boron was convincingly demonstrated to be essential for normal growth of higher plants. However, its biochemical role is not well understood at the moment. Several recent reviews propose that B is implicated in three main processes: keeping cell wall structure, maintaining membrane function, and supporting metabolic activities. However, in the absence of conclusive

Luis Bolaos; Krystyna Lukaszewski; Ildefonso Bonilla; Dale Blevins

2004-01-01

169

Lithium Ion Aqueous Cells.  

National Technical Information Service (NTIS)

Lithium ion aqueous cells were investigated using lithium intercalating compounds as anodes and cathodes. The aqueous electrolyte consisted of 4 to 5 molar solutions of either lithium perchlorate or lithium nitrate which contained lithium hydroxide in mil...

E. J. Plichta W. K. Behl

1995-01-01

170

BRAZING BERYLLIUM FOR AEROSPACE APPLICATIONS  

Microsoft Academic Search

The results are summarized of several research programs directed toward ; producing beryllium brazements for service temperatures above 1000 deg F. Several ; silver base alloys and brazing processes were investigated to determine the ; effects of: (a) brazing temperature, (b) time above the Ag-Be eutectic ; temperature, (c) heating and cooling rates, (d) braze atmosphere and (e) the ;

C. L. Cline; R. A. ONeill

1962-01-01

171

Notes on UHV beryllium windows  

SciTech Connect

Techniques are described for making large ultrahigh vacuum beryllium windows for use in synchrotron radiation installations. Procedures are given for affecting both hard brazed seals and demountable seals involving either lead or copper gaskets. Brazed seals can be made to either stainless steel or copper. Possible alternative methods are suggested.

Hartman, P.L.

1986-10-01

172

Beryllium Interactions in Molten Salts.  

National Technical Information Service (NTIS)

Molten flibe (2LiFDTBeF2) is a candidate as a cooling and tritium breeding media for future fusion power plants. Neutron interactions with the salt will produce tritium and release excess free fluorine ions. Beryllium metal has been demonstrated as an eff...

D. A. Petti G. S. Smolik M. F. Simpson P. J. Pinhero S. Tanaka

2006-01-01

173

Worker Environment Beryllium Characterization Study  

SciTech Connect

This report summarizes the conclusion of regular monitoring of occupied buildings at the Nevada Test Site and North Las Vegas facility to determine the extent of beryllium (Be) contamination in accordance with Judgment of Needs 6 of the August 14, 2003, Minnema Report.

NSTec Environment, Safety, Health & Quality

2009-12-28

174

Galvanic corrosion of beryllium welds  

SciTech Connect

Beryllium is difficult to weld because it is highly susceptible to cracking. The most commonly used filler metal in beryllium welds is Al-12 wt.% Si. Beryllium has been successfully welded using Al-Si filler metal with more than 30 wt.% Al. This filler creates an aluminum-rich fusion zone with a low melting point that tends to backfill cracks. Drawbacks to adding a filler metal include a reduction in service temperature, a lowering of the tensile strength of the weld, and the possibility for galvanic corrosion to occur at the weld. To evaluate the degree of interaction between Be and Al-Si in an actual weld, sections from a mock beryllium weldment were exposed to 0.1 M Cl{sup {minus}} solution. Results indicate that the galvanic couple between Be and the Al-Si weld material results in the cathodic protection of the weld and of the anodic dissolution of the bulk Be material. While the cathodic protection of Al is generally inefficient, the high anodic dissolution rate of the bulk Be during pitting corrosion combined with the insulating properties of the Be oxide afford some protection of the Al-Si weld material. Although dissolution of the Be precipitate in the weld material does occur, no corrosion of the Al-Si matrix was observed.

Hill, M.A.; Butt, D.P.; Lillard, R.S. [Los Alamos National Lab., NM (United States). Materials Corrosion and Environmental Effects Lab.

1997-12-01

175

Investigation of the boron-oxygen network in borate glasses by infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Lithium borate glasses are fast ionic conductors in which the lithium ions conductivity is all the more important as the content in lithium oxide and in lithium salt is higher. In the perspective of their use as electrolytes in solid state micro-batteries, we have studied the conformation of the boron-oxygen network of lithium halides "doped" glasses by MIR spectroscopy. The modifying properties of the lithium oxide on the binary system B2O3-Li2O are investigated by the same technique and the results are used to understand the modifications of the boron-oxygen network induced by the "doping salt". The observed results depend on the type of salt anions: fluoride anions participate directly to the O/B network while chloride and bromide anions are in interstitial position in the glass matrix.

Massot, M.; Julien, C.; Balkanski, M.

1989-05-01

176

Boron neutron capture therapy for malignant gliomas.  

PubMed

Boron neutron capture therapy (BNCT) represents a promising modality for a relatively selective radiation dose delivery to the tumour tissue. Boron-10 nuclei capture slow 'thermal' neutrons preferentially and, upon capture, promptly undergo 10B(n,alpha)7Li reaction. The ionization tracks of energetic and heavy lithium and helium ions resulting from this reaction are only about one cell diameter in length (approximately 14 microm). Because of their high linear energy transfer (LET) these ions have a high relative biological effectiveness (RBE) for controlling tumour growth. The key to effective BNCT of tumours, such as glioblastoma multiforme (GBM), is the preferential accumulation of boron-10 in the tumour, including the infiltrating GBM cells, as compared with that in the vital structures of the normal brain. Provided that a sufficiently high tumour boron-10 concentration (approximately 10(9) boron-10 atoms/cell) and an adequate thermal neutron fluence (approximately 10(12) neutrons/cm2) are achieved, it is the ratio of the boron-10 concentration in tumour cells to that in the normal brain cells that will largely determine the therapeutic gain of BNCT. PMID:10711581

Diaz, A Z; Coderre, J A; Chanana, A D; Ma, R

2000-02-01

177

Beryllium in the environment: a review.  

PubMed

Beryllium is an important industrial metal because of its unusual material properties: it is lighter than aluminum and six times stronger than steel. Often alloyed with other metals such as copper, beryllium is a key component of materials used in the aerospace and electronics industries. Beryllium has a small neutron cross-section, which makes it useful in the production of nuclear weapons and in sealed neutron sources. Unfortunately, beryllium is one of the most toxic elements in the periodic table. It is responsible for the often-fatal lung disease, Chronic Beryllium Disease (CBD) or berylliosis, and is listed as a Class A EPA carcinogen. Coal-fired power plants, industrial manufacturing and nuclear weapons production and disposal operations have released beryllium to the environment. This contamination has the potential to expose workers and the public to beryllium. Despite the increasing use of beryllium in industry, there is surprisingly little published information about beryllium fate and transport in the environment. This information is crucial for the development of strategies that limit worker and public exposure. This review summarizes the current understanding of beryllium health hazards, current regulatory mandates, environmental chemistry, geochemistry and environmental contamination. PMID:12638707

Taylor, Tammy P; Ding, Mei; Ehler, Deborah S; Foreman, Trudi M; Kaszuba, John P; Sauer, Nancy N

2003-02-01

178

Beryllium - A Unique Material in Nuclear Applications  

SciTech Connect

Beryllium, due to its unique combination of structural, chemical, atomic number, and neutron absorption cross section characteristics, has been used successfully as a neutron reflector for three generations of nuclear test reactors at the Idaho National Engineering and Environmental Laboratory (INEEL). The Advanced Test Reactor (ATR), the largest test reactor in the world, has utilized five successive beryllium neutron reflectors and is scheduled for continued operation with a sixth beryllium reflector. A high radiation environment in a test reactor produces radiation damage and other changes in beryllium. These changes necessitate safety analysis of the beryllium, methods to predict performance, and appropriate surveillances. Other nuclear applications also utilize beryllium. Beryllium, given its unique atomic, physical, and chemical characteristics, is widely used as a window for x-rays and gamma rays. Beryllium, intimately mixed with high-energy alpha radiation emitters has been successfully used to produce neutron sources. This paper addresses operational experience and methodologies associated with the use of beryllium in nuclear test reactors and in windows for x-rays and gamma rays. Other nuclear applications utilizing beryllium are also discussed.

T., A. Tomberlin

2004-11-01

179

OVERVIEW OF BERYLLIUM SAMPLING AND ANALYSIS  

SciTech Connect

Because of its unique properties as a lightweight metal with high tensile strength, beryllium is widely used in applications including cell phones, golf clubs, aerospace, and nuclear weapons. Beryllium is also encountered in industries such as aluminium manufacturing, and in environmental remediation projects. Workplace exposure to beryllium particulates is a growing concern, as exposure to minute quantities of anthropogenic forms of beryllium may lead to sensitization and to chronic beryllium disease, which can be fatal and for which no cure is currently known. Furthermore, there is no known exposure-response relationship with which to establish a 'safe' maximum level of beryllium exposure. As a result, the current trend is toward ever lower occupational exposure limits, which in turn make exposure assessment, both in terms of sampling and analysis, more challenging. The problems are exacerbated by difficulties in sample preparation for refractory forms of beryllium, such as beryllium oxide, and by indications that some beryllium forms may be more toxic than others. This chapter provides an overview of sources and uses of beryllium, health risks, and occupational exposure limits. It also provides a general overview of sampling, analysis, and data evaluation issues that will be explored in greater depth in the remaining chapters. The goal of this book is to provide a comprehensive resource to aid personnel in a wide variety of disciplines in selecting sampling and analysis methods that will facilitate informed decision-making in workplace and environmental settings.

Brisson, M

2009-04-01

180

Radiation damage and defect behavior in ion-implanted, lithium counterdoped silicon solar cells  

Microsoft Academic Search

Boron doped silicon n+p solar cells were counterdoped with lithium by ion implantation and the resuitant n+p cells irradiated by 1 MeV electrons. The function of fluence and a Deep Level Transient Spectroscopy (DLTS) was studied to correlate defect behavior with cell performance. It was found that the lithium counterdoped cells exhibited significantly increased radiation resistance when compared to boron

I. Weinberg; S. Mehta; C. K. Swartz

1984-01-01

181

Beryllium Disease Natural History and Exposure-Response.  

National Technical Information Service (NTIS)

This is the first natural history study to determine the progression from beryllium sensitization to disease, as well as the progression from sub clinical beryllium disease. In understanding how beryllium sensitization and disease progresses we will be be...

L. S. Newman

2002-01-01

182

10 CFR 850.20 - Baseline beryllium inventory.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Baseline beryllium inventory. 850.20 Section 850...Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Specific Program Requirements § 850.20 Baseline beryllium inventory. (a) The...

2013-01-01

183

20 CFR 30.508 - What is beryllium sensitivity monitoring?  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2012-04-01 true What is beryllium sensitivity monitoring? 30.508 Section...for Certain Payments § 30.508 What is beryllium sensitivity monitoring? Beryllium sensitivity monitoring shall consist of...

2013-04-01

184

Defense programs beryllium good practice guide  

SciTech Connect

Within the DOE, it has recently become apparent that some contractor employees who have worked (or are currently working) with and around beryllium have developed chronic beryllium disease (CBD), an occupational granulomatous lung disorder. Respiratory exposure to aerosolized beryllium, in susceptible individuals, causes an immunological reaction that can result in granulomatous scarring of the lung parenchyma, shortness of breath, cough, fatigue, weight loss, and, ultimately, respiratory failure. Beryllium disease was originally identified in the 1940s, largely in the fluorescent light industry. In 1950, the Atomic Energy Commission (AEC) introduced strict exposure standards that generally curtailed both the acute and chronic forms of the disease. Beginning in 1984, with the identification of a CBD case in a DOE contractor worker, there was increased scrutiny of both industrial hygiene practices and individuals in this workforce. To date, over 100 additional cases of beryllium-specific sensitization and/or CBD have been identified. Thus, a disease previously thought to be largely eliminated by the adoption of permissible exposure standards 45 years ago is still a health risk in certain workforces. This good practice guide forms the basis of an acceptable program for controlling workplace exposure to beryllium. It provides (1) Guidance for minimizing worker exposure to beryllium in Defense Programs facilities during all phases of beryllium-related work, including the decontamination and decommissioning (D&D) of facilities. (2) Recommended controls to be applied to the handling of metallic beryllium and beryllium alloys, beryllium oxide, and other beryllium compounds. (3) Recommendations for medical monitoring and surveillance of workers exposed (or potentially exposed) to beryllium, based on the best current understanding of beryllium disease and medical diagnostic tests available. (4) Site-specific safety procedures for all processes of beryllium that is likely to generate dusts, mists, fumes, or small particulates. A beryllium exposure control program should minimize airborne concentrations, the potential for and spread of contamination, the number of times individuals are exposed to beryllium, and the number of employees who may be potentially exposed.

Herr, M.

1997-07-01

185

Characterization of physicochemical properties of beryllium aerosols associated with prevalence of chronic beryllium disease.  

PubMed

Little is known about the physicochemical properties of beryllium aerosols associated with increased risk of beryllium sensitization and chronic beryllium disease (CBD). Such information is needed to evaluate whether airborne mass of beryllium is the appropriate metric of exposure or alternatively to provide a scientific basis for using information on particle size, surface area, and chemistry to support an improved exposure limit based on bioavailability through the inhalation and dermal routes of exposure. Thus, we used a suite of analytical techniques to characterize aerodynamically size-fractionated beryllium particles and powders that have been associated in epidemiological studies with higher prevalence of CBD. Aerosol particles were sampled from the ventilation systems of production lines for powders of beryllium metal and beryllium oxide and for ingots of copper-beryllium alloy. End product powders from the metal and oxide production lines were also collected. Particles released during production of beryllium metal were found to be complex, having heterogeneous composition, including reactive species such as fluorine. Powders from beryllium metal production were of high purity with only a minor component of beryllium oxide. Both particles and powders from oxide production were high-purity oxide. Particles released during production of copper-beryllium alloy were heterogeneous, being predominantly copper oxides. Thus, all particles and powders contain at least some beryllium in the form of beryllium oxide. These data justify efforts to thoroughly characterize beryllium aerosol properties when performing exposure assessments. The data also suggest that differences in particle chemical composition, size, number, and surface area may influence bioavailability of beryllium and contribute to risk of CBD. However, a scientific basis does not yet exist to replace mass as the current metric of exposure. PMID:15173904

Stefaniak, Aleksandr B; Hoover, Mark D; Day, Gregory A; Dickerson, Robert M; Peterson, Eric J; Kent, Michael S; Schuler, Christine R; Breysse, Patrick N; Scripsick, Ronald C

2004-03-22

186

Beryllium Lymphocyte Proliferation Test Surveillance Identifies Clinically Significant Beryllium Disease  

PubMed Central

Background Workplace surveillance identifies chronic beryllium disease (CBD) but it remains unknown over what time frame mild CBD will progress to a more severe form. Methods We examined physiology and treatment in 229 beryllium sensitization (BeS) and 171 CBD surveillance-identified cases diagnosed from 1982 to 2002. Never smoking CBD cases (81) were compared to never smoking BeS patients (83) to assess disease progression. We compared CBD machinists to non-machinists to examine effects of exposure. Results At baseline, CBD and BeS cases did not differ significantly in exposure time or physiology. CBD patients were more likely to have machined beryllium. Of CBD cases, 19.3% went on to require oral immunosuppressive therapy. At 30 years from first exposure, measures of gas exchange were significantly worse and total lung capacity was lower for CBD subjects. Machinists had faster disease progression as measured by pulmonary function testing and gas exchange. Conclusions Medical surveillance for CBD identifies individuals at significant risk of disease progression and impairment with sufficient time since first exposure.

Mroz, Margaret M.; Maier, Lisa A.; Strand, Matthew; Silviera, Lori; Newman, Lee S.

2011-01-01

187

The effect of thermal treatment on the metallographic structure of beryllium and dilute beryllium alloys  

Microsoft Academic Search

Electron microscopy and electron-probe microanalysis techniques were ; used to study the microstructure of beryllium and some dilute beryllium alloys. ; The effect of tuermal treatment on the dissemination of impurities and alloying ; elements was investigated with particular reference to the mechanical properties ; of the metal at 600 deg C. In beryllium-iron alloys annealed to improve high-; temperature

G. V. T. Ranzetta; V. D. Scott

1963-01-01

188

Properties of high-strength beryllium wire  

Microsoft Academic Search

1.The ultimate strength of beryllium wire with a purity of 99.9699.99% is lower than that of wire from commercial beryllium; it increases from 54 to 90 kgf\\/mm2 as the diameter of the wire is reduced from 1.3 to 0.19 mm. The strength of annealed wire is independent of the diameter. The ductility is high for wire of high purity beryllium.2.Mechanical

G. S. Koshkarev; G. E. Pletenetskii; A. I. Pikalov; G. F. Tikhinskii

1980-01-01

189

Beryllium Use in the Advanced Test Reactor  

SciTech Connect

The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) began operation in 1967. It makes use of a unique serpentine fuel core design and a beryllium reflector. Reactor control is achieved with rotating beryllium cylinders to which have been fastened plates of hafnium. Over time, the beryllium develops rather high helium content because of nuclear transmutations and begins to swell. The beryllium must be replaced at nominally 10-year intervals. Determination of when the replacement is made is by visual observation using a periscope to examine the beryllium surface for cracking and swelling. Disposition of the irradiated beryllium was once accomplished in the INLs Radioactive Waste Management Complex, but that is no longer possible. Among contributing reasons are high levels of specific radioactive contaminants including transuranics. The INL is presently considering disposition pathways for this irradiated beryllium, but presently is storing it in the canal adjacent to the reactor. Numerous issues are associated with this situation including (1) Is there a need for ultra-low uranium material? (2) Is there a need to recover tritium from irradiated beryllium either because this is a strategic material resource or in preparation for disposal? (3) Is there a need to remove activation and fission products from irradiated beryllium? (4) Will there be enough material available to meet requirements for research reactors (fission and fusion)? In this paper will be discussed the present status of considerations on these issues.

Glen R. Longhurst

2007-12-01

190

MANAGING BERYLLIUM IN NUCLEAR FACILITY APPLICATIONS  

SciTech Connect

Beryllium plays important roles in nuclear facilities. Its neutron multiplication capability and low atomic weight make it very useful as a reflector in fission reactors. Its low atomic number and high chemical affinity for oxygen have led to its consideration as a plasma-facing material in fusion reactors. In both applications, the beryllium and the impurities in it become activated by neutrons, transmuting them to radionuclides, some of which are long-lived and difficult to dispose of. Also, gas production, notably helium and tritium, results in swelling, embrittlement, and cracking, which means that the beryllium must be replaced periodically, especially in fission reactors where dimensional tolerances must be maintained. It has long been known that neutron activation of inherent iron and cobalt in the beryllium results in significant {sup 60}Co activity. In 2001, it was discovered that activation of naturally occurring contaminants in the beryllium creates sufficient {sup 14}C and {sup 94}Nb to render the irradiated beryllium 'Greater-Than-Class-C' for disposal in U.S. radioactive waste facilities. It was further found that there was sufficient uranium impurity in beryllium that had been used in fission reactors up to that time that the irradiated beryllium had become transuranic in character, making it even more difficult to dispose of. In this paper we review the extent of the disposal issue, processes that have been investigated or considered for improving the disposability of irradiated beryllium, and approaches for recycling.

R. Rohe; T. N. Tranter

2011-12-01

191

Beryllium and lithium x-ray lenses at the APS  

Microsoft Academic Search

Compound refractive lenses (CRLs) are arrays of concave lenslets used to focus X-rays. For a given incident X-ray beam energy, the focal length of a CRL depends on the material and shape of the individual lenslets, and in particular is inversely related to the number of lenslets in the array. The throughput of a lens array is heavily affected by

Ali Khounsary; Eric M. Dufresne; Kristina Young; Cameron M. Kewish; Andrew N. Jansen

2006-01-01

192

Viscosity of molten lithium, thorium and beryllium fluorides mixtures  

NASA Astrophysics Data System (ADS)

Considering development of Molten Salt Fast Reactor (MSFR) concept, following Molten Salt fluorides mixtures have been chosen as an object for viscosity studies in this work (in mol%): 78LiF-22ThF4; 71LiF-27ThF4-2BeF2 and 75LiF-20ThF4-5BeF2. Additionally, the effect of the 3 mol% CeF3 additives on viscosity of the molten 75LiF-20ThF4-5BeF2 (mol%) salt mixture has been investigated experimentally. The method of torsional oscillations of cylindrical crucible filled by molten fluorides mixture has been chosen for kinematic viscosity measurement at temperatures up to 800-850 C. In temperature ranges, where melts behave as normal liquids, dependences on viscosity vs. temperature are received: ? = exp [B/T(K)], where ? - kinematic viscosity, m2/s; T - temperature, K. The kinematic viscosity Rout mean squares (RMS) estimated in the assumption about dispersion homoscedasticity is (0.04-0.12) 10-6 (m2/s). Discrepancies left in the data of viscosity for molten mixtures of LiF, BeF2 and ThF4 received by different researchers need further investigations in this area to be continued.

Merzlyakov, Alexander V.; Ignatiev, Victor V.; Abalin, Sergei S.

2011-12-01

193

Viscosity of molten lithium, thorium and beryllium fluorides mixtures  

Microsoft Academic Search

Considering development of Molten Salt Fast Reactor (MSFR) concept, following Molten Salt fluorides mixtures have been chosen as an object for viscosity studies in this work (in mol%): 78LiF22ThF4; 71LiF27ThF42BeF2 and 75LiF20ThF45BeF2. Additionally, the effect of the 3mol% CeF3 additives on viscosity of the molten 75LiF20ThF45BeF2 (mol%) salt mixture has been investigated experimentally. The method of torsional oscillations of cylindrical

Alexander V. Merzlyakov; Victor V. Ignatiev; Sergei S. Abalin

194

Beryllium Abundances in Solar Mass Stars  

NASA Astrophysics Data System (ADS)

Light element abundance analysis allows for a deeper understanding of the chemical composition of a star beneath its surface. Beryllium provides a probe down to 3.5x106 K, where it fuses with protons. In this study, Be abundances were determined for 52 F and G dwarfs selected from a sample of local thin disc stars. These stars were selected by their mass to be in a mass range of 0.9 to 1.1 solar masses as determined by Lambert & Reddy (2004). They have effective temperatures from 5600 to 6400 K, and their metallicities [Fe/H] -0.65 to +0.11. The data were taken over several nights, with forty-six spectra taken with the Keck HIRES instrument and six spectra on the Canada France Hawaii Telescope (CFHT) using the Gecko spectrograph. The abundances were calculated via spectral synthesis, fitting a 4 region around the resonance lines of Be II. The data were then analyzed to investigate the Be abundance as a function of age, temperature, and metallicity and its relation to the lithium abundance for this narrow mass range. Be is found to increase with metallicity and the linear relationship evident when extended to metallicities down to -4.0 dex with slope 0.86 0.02. The relation of the Be abundance to effective temperature is dependent upon metallicity, but when metallicity effects are taken into account, there is a spread 1.2 dex. We find a 1.5 dex spread in A(Be) when plotted against age, with the largest spread occurring from 6-8 Gyr. The relation with Li is found to be linear with slope 0.36 0.06 for the temperature regime of 5900-6300 K. This research was conducted through the Research Experiences for Undergraduate (REU) program at the University of Hawaii's Institute for Astronomy and was funded by the NSF.

Krugler, Julie A.; Boesgaard, A. M.

2007-12-01

195

The beryllium "double standard" standard.  

PubMed

Brush Wellman, the world's leading producer and supplier of beryllium products, has systematically hidden cases of beryllium disease that occurred below the threshold limit value (TLV) and lied about the efficacy of the TLV in published papers, lectures, reports to government agencies, and instructional materials prepared for customers and workers. Hypocritically, Brush Wellman instituted a zero exposure standard for corporate executives while workers and customers were told the 2 microgram standard was "safe." Brush intentionally used its workers as "canaries for the plant," and referred to them as such. Internal documents and corporate depositions indicate that these actions were intentional and that the motive was money. Despite knowledge of the inadequacy of the TLV, Brush has successfully used it as a defense against lawsuits brought by injured workers and as a sales device to provide reassurance to customers. Brush's policy has reaped an untold number of victims and resulted in mass distribution of beryllium in consumer products. Such corporate malfeasance is perpetuated by the current market system, which is controlled by an organized oligopoly that creates an incentive for the neglect of worker health and safety in favor of externalizing costs to victimized workers, their families, and society at large. PMID:14758859

Egilman, David S; Bagley, Sarah; Biklen, Molly; Golub, Alison Stern; Bohme, Susanna Rankin

2003-01-01

196

Defect-induced Symmetry Distortions in Doped Cubic Boron Nitride  

NASA Astrophysics Data System (ADS)

We have studied the substitution of silicon and beryllium for boron in cubic boron nitride with several first-principles methods. The Be and Si defects are proto-typical p- and n-type dopants respectively.(O. Mishima, S. Yamoka, and O. Fukunaga, Science 238), 181 (1987). The substitutionals have orbitally degenerate ground states leading to symmetry-lowering distortions of the Td point-group symmetry about the boron sites. Calculated IR absorption modes associated with the defects are compared with recent experimental determination of bulk modes.(M. I. Eremets, M. Gauthier, A. Polian, J. C. Chervin, J. M. Besson, G. A. Dubitskii, and Y. Y. Semenova, Phys. Rev. B 52), 8854 (1995). Changes in Fermi contact interaction terms as an effect of the distortions are discussed as a possible way of characterizing the distortions experimentally.

Patton, David C.; Harrison, Joseph G.

1996-03-01

197

Dose point kernel for boron-11 decay and the cellular S values in boron neutron capture therapy.  

PubMed

The study of the radiobiology of boron neutron capture therapy is based on the cellular level dosimetry of boron-10's thermal neutron capture reaction 10B(n,alpha)7Li, in which one 1.47 MeV helium-4 ion and one 0.84 MeV lithium-7 ion are spawned. Because of the chemical preference of boron-10 carrier molecules, the dose is heterogeneously distributed in cells. In the present work, the (scaled) dose point kernel of boron-11 decay, called 11B-DPK, was calculated by GEANT4 Monte Carlo simulation code. The DPK curve drops suddenly at the radius of 4.26 microm, the continuous slowing down approximation (CSDA) range of a lithium-7 ion. Then, after a slight ascending, the curve decreases to near zero when the radius goes beyond 8.20 microm, which is the CSDA range of a 1.47 MeV helium-4 ion. With the DPK data, S values for nuclei and cells with the boron-10 on the cell surface are calculated for different combinations of cell and nucleus sizes. The S value for a cell radius of 10 microm and a nucleus radius of 5 microm is slightly larger than the value published by Tung et al. [Appl. Radiat. Isot. 61, 739-743 (2004)]. This result is potentially more accurate than the published value since it includes the contribution of a lithium-7 ion as well as the alpha particle. PMID:17278826

Ma, Yunzhi; Geng, JinPeng; Gao, Song; Bao, Shanglian

2006-12-01

198

Lithium neurotoxicity.  

PubMed

Inspite of the advent of newer antimanic drugs, lithium carbonate remains widely used in the treatment and prevention of manic-depressive illness. However care has to be exercised due to its low therapeutic index. The central nervous system and renal system are predominantly affected in acute lithium intoxication and is potentially lethal. The more common side effect involves the central nervous system. It occurs early and is preventable. We describe three cases of lithium toxicity admitted to Johor Bahru Hospital, with emphasis on its neurological preponderance. PMID:11732087

Suraya, Y; Yoong, K Y

2001-09-01

199

Lithium battery  

SciTech Connect

In a lithium battery having a negative electrode formed with lithium as active material and the positive electrode formed with manganese dioxide, carbon fluoride or the like as the active material, the discharge capacity of the negative electrode is made smaller than the discharge capacity of the positive electrode, whereby a drop in the battery voltage during the final discharge stage is steepened, and prevents a device using such a lithium battery as a power supply from operating in an unstable manner, thereby improving the reliability of such device.

Ikeda, H.; Nakaido, S.; Narukara, S.

1983-08-16

200

Tritium migration in the materials proposed for fusion reactors: Li2TiO3 and beryllium  

NASA Astrophysics Data System (ADS)

The results of tritium and helium gas release from lithium ceramics samples Li2TiO3 irradiated at the WWR-K reactor (Almaty, Kazakhstan) and from beryllium samples irradiated at the BN-350 reactor (Aktau, Kazakhstan) and the IVG.1M reactor (Kurchatov, Kazakhstan) are presented. Experimentally obtained thermal desorption (TDS) spectra have shown that the dependence of tritium release from lithium ceramics has a complicated behavior and to a large extent depends on lithium ceramics type. Nevertheless, it was found that the total amount of tritium released from all types of lithium ceramics has the same order of magnitude, equal to about 1011 Bq/kg. It was found that in the temperature range from 523 K to 1373 K the process of tritium release from lithium ceramics involves volume diffusion and thermoactivated tritium release from the accumulation centers generated under irradiation. TDS of beryllium samples enables us to obtain characteristics of tritium and helium release during linear heating, to determine integrated quantities of generated helium and tritium, and to determine parameters of release processes.

Kulsartov, T. V.; Gordienko, Yu. N.; Tazhibayeva, I. L.; Kenzhin, E. A.; Barsukov, N. I.; Sadvakasova, A. O.; Kulsartova, A. V.; Zaurbekova, Zh. A.

2013-11-01

201

Laser welding beryllium in a deuterium atmosphere  

Microsoft Academic Search

Methods for laser welding beryllium in high pressure deuterium atmospheres were investigated. The methods included direct fusion welds, braze welds and fusion welds in aluminum coatings on beryllium. Bead-on-plate laser welds were made in deuterium, argon and helium atmospheres. Severe porosity was observed in welds made in deuterium atmospheres. Weld cracking was observed in welds made in inert gas atmospheres.

G. E. Faulkner; T. J. Ramos; J. R. Murchie

1982-01-01

202

JOWOG 22B beryllium meeting presentations.  

National Technical Information Service (NTIS)

A broad range of topics were discussed at the JOWOG meeting held May 1993 at the Rocky Flats Plant. Attendees came from US DOE laboratories and from the United Kingdom. Presented topics include: the status of commercial beryllium, beryllium technology in ...

J. Hanafee

1993-01-01

203

Beryllium isotope geochemistry in tropical river basins  

Microsoft Academic Search

The distributions of beryllium-9 and beryllium-10 in rivers within the Orinoco and Amazon basins have been examined to extend the understanding of their geochemical cycles and to develop their use both in geochronometry, and in studying erosional processes. Analyses of ⁹Be in dissolved and suspended material from rivers with a wide range of chemical compositions indicate that its geochemistry is

E. T. Brown; J. M. Edmond; G. M. Raisbeck; D. L. Bourles; F. Yiou; C. I. Measures

1992-01-01

204

Process for synthesis of beryllium chloride dietherate  

DOEpatents

A low temperature method of producing beryllium chloride dietherate through the addition of hydrogen chloride gas to a mixture of beryllium metal in ether in a reaction vessel is described. A reflux condenser provides an exit for hydrogen produced form the reaction. A distillation condenser later replaces the reflux condenser for purifying the resultant product.

Bergeron, Charles (Baton Rouge, LA); Bullard, John E. (Kendall Park, NJ); Morgan, Evan (Lynchburg, VA)

1991-01-01

205

Inhibited Solid Propellant Composition Containing Beryllium Hydride.  

National Technical Information Service (NTIS)

An object of this invention is to provide a composition of beryllium hydride and carboxy-terminated polybutadiene which is stable. Another object of this invention is to provide a method for inhibiting the reactivity of beryllium hydride toward carboxy-te...

W. W. Thompson

1978-01-01

206

Some characteristics of fine beryllium particle combustion  

NASA Astrophysics Data System (ADS)

Beryllium dust will be produced under plasma interaction with beryllium armor of the first wall in ITER. Exothermal reaction of this dust with water steam or air, which can leak into the reactor vacuum chamber in some accidents, gives concern in respect to reactor safety. Results of studies devoted to combustion of fine beryllium particles are reviewed in the paper. A chemically active medium and elevated temperature are prerequisite to the combustion of beryllium particles. Their ignition is hampered by oxide films, which form a diffusion barrier on the particle surface as a result of pre-flame oxidation. The temperature to initiate combustion of particles depends on flame temperature, particle size, composition of combustible mixture, heating rate and other factors. In mixtures enriched with combustible, the flame temperature necessary to ignite individual particles approaches the beryllium boiling temperature.

Davydov, D. A.; Kholopova, O. V.; Kolbasov, B. N.

2007-08-01

207

Assessment of LANL beryllium waste management documentation  

SciTech Connect

The objective of this report is to determine present status of the preparation and implementation of the various high priority documents required to properly manage the beryllium waste generated at the Laboratory. The documents being assessed are: Waste Acceptance Criteria, Waste Characterization Plan, Waste Certification Plan, Waste Acceptance Procedures, Waste Characterization Procedures, Waste Certification Procedures, Waste Training Procedures and Waste Recordkeeping Procedures. Beryllium is regulated (as a dust) under 40 CFR 261.33 as ``Discarded commercial chemical products, off specification species, container residues and spill residues thereof.`` Beryllium is also identified in the 3rd thirds ruling of June 1, 1990 as being restricted from land disposal (as a dust). The beryllium waste generated at the Laboratory is handled separately because beryllium has been identified as a highly toxic carcinogenic material.

Danna, J.G.; Jennrich, E.A.; Lund, D.M. [Rogers and Associates Engineering Corp., Salt Lake City, UT (United States); Davis, K.D.; Hoevemeyer, S.S. [Wastren, Inc., Idaho Falls, ID (United States)

1991-04-01

208

Assessment of LANL beryllium waste management documentation  

SciTech Connect

The objective of this report is to determine present status of the preparation and implementation of the various high priority documents required to properly manage the beryllium waste generated at the Laboratory. The documents being assessed are: Waste Acceptance Criteria, Waste Characterization Plan, Waste Certification Plan, Waste Acceptance Procedures, Waste Characterization Procedures, Waste Certification Procedures, Waste Training Procedures and Waste Recordkeeping Procedures. Beryllium is regulated (as a dust) under 40 CFR 261.33 as Discarded commercial chemical products, off specification species, container residues and spill residues thereof.'' Beryllium is also identified in the 3rd thirds ruling of June 1, 1990 as being restricted from land disposal (as a dust). The beryllium waste generated at the Laboratory is handled separately because beryllium has been identified as a highly toxic carcinogenic material.

Danna, J.G.; Jennrich, E.A.; Lund, D.M. (Rogers and Associates Engineering Corp., Salt Lake City, UT (United States)); Davis, K.D.; Hoevemeyer, S.S. (Wastren, Inc., Idaho Falls, ID (United States))

1991-04-01

209

BERYLLIUM MEASUREMENT IN COMMERCIALLY AVAILABLE WET WIPES  

SciTech Connect

Analysis for beryllium by fluorescence is now an established method which is used in many government-run laboratories and commercial facilities. This study investigates the use of this technique using commercially available wet wipes. The fluorescence method is widely documented and has been approved as a standard test method by ASTM International and the National Institute for Occupational Safety and Health (NIOSH). The procedure involves dissolution of samples in aqueous ammonium bifluoride solution and then adding a small aliquot to a basic hydroxybenzoquinoline sulfonate fluorescent dye (Berylliant{trademark} Inc. Detection Solution Part No. CH-2) , and measuring the fluorescence. This method is specific to beryllium. This work explores the use of three different commercial wipes spiked with beryllium, as beryllium acetate or as beryllium oxide and subsequent analysis by optical fluorescence. The effect of possible interfering metals such as Fe, Ti and Pu in the wipe medium is also examined.

Youmans-Mcdonald, L.

2011-02-18

210

Lithium battery  

Microsoft Academic Search

The invention features the use of additives such as 2-methylfuran or related cyclic or acyclic organic compounds in non-aqueous electrolyte-containing secondary lithium cells for improving the cycle life of such cells.

K. M. Abraham; B. Brummer; J. S. Foos

1984-01-01

211

Production of CuBe Master from Beryllium Oxide  

Microsoft Academic Search

This paper reviews the process for the commercial production of beryllium-copper master alloy. Emphasis is placed on basics of carbothermic reduction of beryllium oxide in the presence of copper. The product is typically a 4% beryllium copper master alloy which is the feedstock for high performance beryllium copper alloys.

W. RAYMOND CRIBB; SABIT ALI

1994-01-01

212

Technical issues for beryllium use in fusion blanket applications  

SciTech Connect

Beryllium is an excellent non-fissioning neutron multiplier for fusion breeder and fusion electric blanket applications. This report is a compilation of information related to the use of beryllium with primary emphasis on the fusion breeder application. Beryllium resources, production, fabrication, properties, radiation damage and activation are discussed. A new theoretical model for beryllium swelling is presented.

McCarville, T.J.; Berwald, D.H.; Wolfer, W.; Fulton, F.J.; Lee, J.D.; Maninger, R.C.; Moir, R.W.; Beeston, J.M.; Miller, L.G.

1985-01-01

213

Lung cancer case-control study of beryllium workers  

Microsoft Academic Search

Background Cohort mortality studies have found elevated lung cancer mortality among beryllium-exposed workers, but none evaluated the association between beryllium exposure level and lung cancer risk. A nested case-control study of lung cancer within a beryllium processing plant was conducted to investigate the relationship between level of beryllium exposure and lung cancer. Methods Lung cancer cases were identified by mortality

Wayne T. Sanderson; Elizabeth M. Ward; Kyle Steenland; Martin R. Petersen

2001-01-01

214

BERYLLIUM CONTROL PROGRAM IN THE N-REACTOR FUELS OPERATION  

Microsoft Academic Search

The controls necessary to protect personnel from beryllium in the ; preparation of NPR fuel elements of uranium metal clad with Zircaloy and an alloy ; of Zircaloy and beryllium are described. All equipment where airborne beryllium ; might be generated is connected to the beryllium exhaust system, which consists ; of a primary fllter at each of the stations

1963-01-01

215

Patch testing with beryllium alloy samples in guinea pigs.  

PubMed

An experimental study was conducted in guinea pigs for the predictive assessment of the beryllium alloy hazard in occupational exposure of the skin to beryllium compounds. Guinea pigs were sensitized to beryllium sulfate according to the maximized Magnusson and Kligman test, and challenged with beryllium alloys and metallic copper, beryllium and aluminum samples. Results showed a delayed skin hypersensitivity reaction in 30 to 60% of pre-sensitized guinea pigs challenged with copper-beryllium alloys and aluminum-beryllium alloy. An inflammatory follicular reaction was induced by copper in both controls and pre-sensitized guinea pigs. PMID:8833464

Zissu, D; Binet, S; Cavelier, C

1996-03-01

216

Beryllium recycling in the United States in 2000  

USGS Publications Warehouse

This report describes the flow of beryllium in the United States in 2000 with emphasis on the extent to which beryllium was either recycled or reused. Beryllium was recycled mostly from new scrap that was generated during the manufacture of beryllium-related components. In 2000, about 35 metric tons of beryllium was either recycled or reused, about 14 percent of which was derived from old scrap. The beryllium recycling rate was calculated to be about 10 percent, and beryllium scrap recycling efficiency, about 7 percent.

Cunningham, Larry D.

2004-01-01

217

Beryllium Recycling in the United States in 2000  

USGS Publications Warehouse

This report describes the flow of beryllium in the United States in 2000 with emphasis on the extent to which beryllium was either recycled or reused. Beryllium was recycled mostly from new scrap that was generated during the manufacture of beryllium-related components. In 2000, about 35 metric tons of beryllium was either recycled or reused, about 14 percent of which was derived from old scrap. The beryllium recycling rate was calculated to be about 10 percent, and beryllium scrap recycling efficiency, about 7 percent.

Cunningham, Larry D.

2003-01-01

218

40 CFR 468.20 - Applicability; description of the beryllium copper forming subcategory.  

Code of Federal Regulations, 2010 CFR

...Applicability; description of the beryllium copper forming subcategory. 468...FORMING POINT SOURCE CATEGORY Beryllium Copper Forming Subcategory § 468...Applicability; description of the beryllium copper forming subcategory....

2010-07-01

219

40 CFR 468.20 - Applicability; description of the beryllium copper forming subcategory.  

Code of Federal Regulations, 2010 CFR

...Applicability; description of the beryllium copper forming subcategory. 468...FORMING POINT SOURCE CATEGORY Beryllium Copper Forming Subcategory § 468...Applicability; description of the beryllium copper forming subcategory....

2009-01-01

220

40 CFR 468.20 - Applicability; description of the beryllium copper forming subcategory.  

Code of Federal Regulations, 2013 CFR

...Applicability; description of the beryllium copper forming subcategory. 468...FORMING POINT SOURCE CATEGORY Beryllium Copper Forming Subcategory § 468...Applicability; description of the beryllium copper forming subcategory....

2013-07-01

221

40 CFR 468.20 - Applicability; description of the beryllium copper forming subcategory.  

Code of Federal Regulations, 2011 CFR

...Applicability; description of the beryllium copper forming subcategory. ...FORMING POINT SOURCE CATEGORY Beryllium Copper Forming Subcategory ...Applicability; description of the beryllium copper forming...

2011-07-01

222

The effects of lithium counterdoping on radiation damage and annealing in n(+)p silicon solar cells  

Microsoft Academic Search

Boron-doped silicon n(+)p solar cells were counterdoped with lithium by ion implantation and the resultant n(+)p cells irradiated by 1 MeV electrons. Performance parameters were determined as a function of fluence and a deep level transient spectroscopy (DLTS) study was conducted. The lithium counterdoped cells exhibited significantly increased radiation resistance when compared to boron doped control cells. Isochronal annealing studies

I. Weinberg; H. W. Brandhorst Jr.; S. Mehta; C. K. Swartz

1984-01-01

223

Beryllium health effects in the era of the beryllium lymphocyte proliferation test.  

PubMed

The beryllium lymphocyte proliferation test (BeLPT) has revolutionized our approach to the diagnosis, screening, and surveillance of beryllium health effects. Based on the development of a beryllium-specific cell-mediated immune response, the BeLPT has allowed us to define early health effects of beryllium, including beryllium sensitization (BeS), and chronic beryllium disease (CBD) at a subclinical stage. The use of this test as a screening tool has improved our understanding of these health effects. From a number of studies it is apparent that BeS precedes CBD and develops after as little as 9 weeks of beryllium exposure. CBD occurs within 3 months and up to 30 years after initial beryllium exposure. Exposure-response variables have been associated with BeS/CBD, including work as a machinist, chemical or metallurgical operator, laboratory technician, work in ceramics or beryllium metal production, and years of beryllium exposure. Recent studies have found BeS and CBD in workplaces in which the majority of exposures were below the 2 microg/m3 OSHA time-weighted average (TWA). Ideally, the BeLPT would be used in surveillance aimed at defining other risk-related processes, determining exposure variables which predict BeS and CBD, and defining the exposure level below which beryllium health effects do not occur. Unfortunately, the BeLPT can result in false negative tests and still requires an invasive procedure, a bronchoscopy, for the definitive diagnosis of CBD. Thus, research is needed to establish new tests to be used alone or in conjunction with the BeLPT to improve our ability to detect early beryllium health effects. PMID:11370931

Maier, L A

2001-05-01

224

THE IDAHO NATIONAL LABORATORY BERYLLIUM TECHNOLOGY UPDATE  

SciTech Connect

A Beryllium Technology Update meeting was held at the Idaho National Laboratory on July 18, 2007. Participants came from the U.S., Japan, and Russia. There were two main objectives of this meeting. One was a discussion of current technologies for beryllium in fission reactors, particularly the Advanced Test Reactor and the Japan Materials Test Reactor, and prospects for material availability in the coming years. The second objective of the meeting was a discussion of a project of the International Science and Technology Center regarding treatment of irradiated beryllium for disposal. This paper highlights discussions held during that meeting and major conclusions reached

Glen R. Longhurst

2007-12-01

225

A study on the beryllium lymphocyte transformation test and the beryllium levels in working environment.  

PubMed

The relationship between airborne concentration of beryllium in the working environment and workers' beryllium lymphocyte transformation test (Be-LTT) values was examined based on data obtained from a four-year survey (1992-1995) conducted at beryllium-copper alloy manufacturing factories. This study showed that the T cells of workers continuously exposed to beryllium of more than 0.01 microgram/m3 could be activated and that the cell-mediated immune response of workers could be promoted. On the other hand, the Be-LTT of workers exposed to beryllium levels of less than 0.01 microgram/m3 was shown to be unaffected by beryllium. These findings suggest that beryllium sensitization is not manifested when level of beryllium in working environment are less than 0.01 microgram/m3. Therefore, in such cases workers do not develop Chronic beryllium disease (CBD). We concluded that the Be-LTT can be applied as a medical indicator to detect the development of CBD. PMID:9248221

Yoshida, T; Shima, S; Nagaoka, K; Taniwaki, H; Wada, A; Kurita, H; Morita, K

1997-07-01

226

The Evaluation of Lithium Hydride for Use in a Space Nuclear Reactor Shield, Including a Historical Perspective  

Microsoft Academic Search

LiH was one of the five primary shield materials the NRPCT intended to develop (along with beryllium, boron carbide, tungsten, and water) for potential Prometheus application. It was also anticipated that B metal would be investigated for feasibility at a low level of effort. LiH historically has been selected as a low mass, neutron absorption material for space shields (Systems

D. Poeth

2005-01-01

227

40 CFR 63.11166 - What General Provisions apply to primary beryllium production facilities?  

Code of Federal Regulations, 2010 CFR

...General Provisions apply to primary beryllium production facilities? 63.11166...Cadmium, and Beryllium Primary Beryllium Production Facilities § 63.11166...General Provisions apply to primary beryllium production facilities?...

2009-07-01

228

40 CFR 63.11166 - What General Provisions apply to primary beryllium production facilities?  

Code of Federal Regulations, 2010 CFR

...General Provisions apply to primary beryllium production facilities? 63.11166...Cadmium, and Beryllium Primary Beryllium Production Facilities § 63.11166...General Provisions apply to primary beryllium production facilities?...

2010-07-01

229

Liposomal boron delivery for neutron capture therapy.  

PubMed

Tumor cell destruction in boron neutron capture therapy (BNCT) is due to the nuclear reaction between (10)B and thermal neutrons. The thermal neutrons have an energy of 0.025 eV, clearly below the threshold energy required to ionize tissue components. However, neutron capture by (10)B produces lithium ion and helium (alpha-particles), which are high linear energy transfer (LET) particles, and dissipate their kinetic energy before traveling one cell diameter (5-9 microm) in biological tissues, ensuring their potential for precise cell killing. BNCT has been applied clinically for the treatment of malignant brain tumors, malignant melanoma, head and neck cancer, and hepatoma using two boron compounds: sodium borocaptate (Na(2)(10)B(12)H(11)SH; Na(2)(10)BSH) and l-p-boronophenylalanine (l-(10)BPA). These low molecular weight compounds are cleared easily from the cancer cells and blood. Therefore, high accumulation and selective delivery of boron compounds into tumor tissues are most important to achieve effective BNCT and to avoid damage of adjacent healthy cells. Much attention has been focused on the liposomal drug delivery system (DDS) as an attractive, intelligent technology of targeting and controlled release of (10)B compounds. Two approaches have been investigated for incorporation of (10)B into liposomes: (1) encapsulation of (10)B compounds into liposomes and (2) incorporation of (10)B-conjugated lipids into the liposomal bilayer. Our laboratory has developed boron ion cluster lipids for application of the latter approach. In this chapter, our boron lipid liposome approaches as well as recent developments of the liposomal boron delivery system are summarized. PMID:19913168

Nakamura, Hiroyuki

2009-01-01

230

Radiation damage and defect behavior in ion-implanted, lithium counterdoped silicon solar cells  

SciTech Connect

Boron doped silicon n+p solar cells were counterdoped with lithium by ion implanation and the resultant n+p cells irradiated by 1 MeV electrons. The function of fluence and a Deep Level Transient Spectroscopy (DLTS) was studied to correlate defect behavior with cell performance. It was found that the lithium counterdoped cells exhibited significantly increased radiation resistance when compared to boron doped control cells. It is concluded that the annealing behavior is controlled by dissociation and recombination of defects. The DLTS studies show that counterdoping with lithium eliminates at least three deep level defects and results in three new defects. It is speculated that the increased radiation resistance of the counterdoped cells is due primarily to the interaction of lithium with oxygen, single vacancies and divacancies and that the lithium-oxygen interaction is the most effective in contributing to the increased radiation resistance.

Weinberg, I.; Mehta, S.; Swartz, C.K.

1984-01-01

231

Cylinder Confined Ion Beam Beryllium Sputtering.  

National Technical Information Service (NTIS)

Cylinder sputtering of beryllium films on laser targets at deposition rates of 12 micrometers per hour has been achieved. The sputtering technique incorporates two symmetrically opposed guns and thus provides a more uniform deposition than a single gun co...

D. J. Sharp

1985-01-01

232

Chronic Beryllium Disease Prevention Program Report  

SciTech Connect

This document describes how Lawrence Livermore National Laboratory (LLNL) meets the requirements and management practices of federal regulation 10 CFR 850, 'Chronic Beryllium Disease Prevention Program (CBDPP).' This revision of the LLNL CBDPP incorporates clarification and editorial changes based on lessons learned from employee discussions, observations and reviews of Department of Energy (DOE) Complex and commercial industry beryllium (Be) safety programs. The information is used to strengthen beryllium safety practices at LLNL, particularly in the areas of: (1) Management of small parts and components; and (2) Communication of program status to employees. Future changes to LLNL beryllium activities and on-going operating experience will be incorporated into the program as described in Section S, 'Performance Feedback.'

Lee, S

2012-03-29

233

BERYLLIUM DIFFUSION OF RUBY AND SAPPHIRE  

Microsoft Academic Search

Over the past two years, the heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800C has become a major issue in the gem trade. Although initially only orange to orangy pink (\\

John L. Emmett; Kenneth Scarratt; Shane F. McClure; Thomas Moses; Troy R. Douthit; Richard Hughes; Steven Novak; James E. Shigley; Wuyi Wang; Owen Bordelon; Robert E. Kane

234

Nitrogen reactivity toward beryllium: surface reactions  

NASA Astrophysics Data System (ADS)

Recent experiments with nitrogen as a seeding gas in fusion plasma devices together with the option of using beryllium as an armor material in the future ITER tokamak (International Thermonuclear Experimental Reactor) have raised new interest in the interactions of beryllium surfaces with nitrogen (atomic or molecular). The strong reactivity of nitrogen implies the formation of beryllium nitrite and, in conjunction with oxygen and other possible impurities, experimentalists have to consider the probability of generating various complex moieties such as imine, amine or oxyamine, and amide radicals. This chemistry would obviously dramatically perturb the plasma, and quantum investigations can be of great predictive help. Nitrogen adsorption on beryllium basal surfaces is investigated through quantum density functional theory. Different situations are examined: molecular or atomic nitrogen reactions; nitride radical adsorption or formation on surfaces; hydrogen retention on surfaces; combined nitrogen/oxygen reactivity and hydrogen retention. A tentative comparison with experiment is also proposed.

Allouche, A.

2013-06-01

235

Nitrogen reactivity toward beryllium: surface reactions.  

PubMed

Recent experiments with nitrogen as a seeding gas in fusion plasma devices together with the option of using beryllium as an armor material in the future ITER tokamak (International Thermonuclear Experimental Reactor) have raised new interest in the interactions of beryllium surfaces with nitrogen (atomic or molecular). The strong reactivity of nitrogen implies the formation of beryllium nitrite and, in conjunction with oxygen and other possible impurities, experimentalists have to consider the probability of generating various complex moieties such as imine, amine or oxyamine, and amide radicals. This chemistry would obviously dramatically perturb the plasma, and quantum investigations can be of great predictive help. Nitrogen adsorption on beryllium basal surfaces is investigated through quantum density functional theory. Different situations are examined: molecular or atomic nitrogen reactions; nitride radical adsorption or formation on surfaces; hydrogen retention on surfaces; combined nitrogen/oxygen reactivity and hydrogen retention. A tentative comparison with experiment is also proposed. PMID:23594802

Allouche, A

2013-04-18

236

Beryllium-aluminum alloys for investment castings  

SciTech Connect

Beryllium-aluminum alloys containing greater than 60 wt % beryllium are very favorable materials for applications requiring light weight and high stiffness. However, when produced by traditional powder metallurgical methods, these alloys are expensive and have limited applications. To reduce the cost of making beryllium-aluminum components, Nuclear Metals Inc. (NMI) and Lockheed Martin Electronics and Missiles have recently developed a family of patented beryllium-aluminum alloys that can be investment cast. Designated Beralcast, the alloys can achieve substantial weight savings because of their high specific strength and stiffness. In some cases, weight has been reduced by up to 50% over aluminum investment casting. Beralcast is now being used to make thin wall precision investment castings for several advanced aerospace applications, such as the RAH-66 Comanche helicopter and F-22 jet fighter. This article discusses alloy compositions, properties, casting method, and the effects of cobalt additions on strength.

Nachtrab, W.T.; Levoy, N. [Nuclear Metals Inc., Concord, MA (United States)

1997-05-01

237

Study of Lithium on Molybdenum substrates in IIAX (Ion surface Inter Action Surface eXperiment)  

NASA Astrophysics Data System (ADS)

Plasma Facing Component(PFC) materials are critical to fusion reactor development. There is no one material that functions as an ideal PFC material. Coatings are applied to control the interaction between plasmas and the surrounding material. Boronization and lithiation are the most common methods of wall conditioning techniques that are currently used in tokamaks. In this work, we investigate lithium on molybdenum substrates for its wetting properties and erosion behavior. To understand the effect of boronization on wetting properties of lithium, a set of experiments have been conducted in the newly built facility, where liquid lithium is dropped on to a heated molybdenum substrate and the contact angle of lithium on substrate is measured. It is found that lithium wets both the molybdenum and the boronized molybdenum substrates. When lithium is sputtered, it has been observed that 55-65% of the sputtered particles are ions [1] and the sheath returns them to the wall. Li on top of other layers may act differently. To examine this phenomenon and assess erosion measurements of lithium on mixed materials (Li/Mo, Li/B/Mo),a methodology to measure ionization fraction of the sputtered lithium in the IIAX facility is also presented. Work supported by DOE/ALPS contract: DEFG02- 99ER54515.[4pt] [1] J.P.Allain and D.N.Ruzic,Nucl.Fusion 42 (2002), pp. 202--210.

Raman, Priya; Groll, Andrew; Andruczyk, Daniel; Surla, Vijay; Ruzic, David

2011-11-01

238

Gravimetric determination of beryllium with cupferron  

Microsoft Academic Search

Beryllium has been determined with cupferron by precipitating the metal at pH 5.8. The complex can be weighed directly as Be (C6H5O2N2)2 containing 3.18% of the metal after drying at 110C. The metal has also been separated with cupferron masking iron (III), aluminium, cerium, thorium, copper, nickel, cobalt, zinc and cadmium with EDTA The beryllium content of beryl has been

Jyotirmoy Das; Siddheswar Baneerjee

1962-01-01

239

Beryllium R&D for fusion applications  

Microsoft Academic Search

Beryllium is one of the primary candidates as both plasma-facing material (PFM) and neutron multiplier in the next-step fusion reactors. Both sintered-product blocks and pebbles are considered in fusion reactor designs. Beryllium evaporated on carbon tiles has also been used in Joint European Torus (JET) and may be considered for other designs. Future efforts are directed toward the pebble form

F. Scaffidi-Argentina; G. R. Longhurst; V. Shestakov; H. Kawamura

2000-01-01

240

Carcinogenicity of beryllium: reivew of the literature  

SciTech Connect

The carcinogenicity of beryllium (Be) is reviewed. At least 17 different senior authors have published 27 different scientific articles which demonstrate the carcinogenicity of 13 different beryllium compounds. Osteogenic sarcomas can be induced in rabbits by the intravenous injection or by the inhalation of Be compounds. Lung cancer can be induced in rats and monkeys by intratracheal injections and inhalation exposures. The first published report on the carcinogenicity of Be was in 1946.

Groth, D.H.

1980-02-01

241

Containerless processing of beryllium. Final report  

Microsoft Academic Search

Melting and solidification of a beryllium alloy containing 1.5% BeO by weight in the weightless environment of space has produced cast beryllium with a relatively uniform dispersion of BeO throughout. Examination of the cast material shows that it is coarse grained, although the BeO is not heavily agglomerated in the flight specimen. Ground-based comparison experiments show extreme agglomeration and segregation

G. Wouch; G. H. Keith; R. T. Frost; N. P. Pinto

1977-01-01

242

Helium-cooled, flibe breeder, beryllium multiplier blanket  

SciTech Connect

The concept described for the blanket surrounding a fusion reaction chamber is based on the use of molten fluoride salts to convert fusion energy into electricity and to breed the tritium fuel for the fusion power plant. Helium cools the first-wall and the blanket internals, which consist of a bed of beryllium balls in which neutrons are multiplied. The neutrons are used to breed tritium and also to release extra energy in exothermic nuclear reactions. Tritium is bred in the molten Flibe salt (LiF + BeF/sub 2/) that flows slowly (about 0.1 m/s) in steel tubes and is removed from the salt and the helium by processing both streams. Because the solubility of tritium in Flibe salt is so low, there is a strong driving force for tritium permeation. A 10-..mu..mthick tungsten permeation barrier, deposited by chemical vapor deposition on the salt-carrying tubes, is proposed for preventing excessive tritium permeation into the helium stream. A 1-mm-thick aluminum jacket on the steel steam generator tubes is proposed to prevent excessive tritium permeation into the steam system. Flibe salt has safety advantages with respect to large accidents in that it will not react with air or water, in contrast to liquid lithium. For the first time, a method is proposed for recycling solid material in fusion blankets. To accomplish this, beryllium pebbles were chosen because the pebbles can be loaded into the blanket after manufacturing and, to accommodate radiation-induced swelling, can be moved periodically by flowing. Once the balls have reached their radiation damage lifetime, they can be removed from the blanket for refabrication and recycle.

Moir, R.W.; Berwald, D.H.; De Van, J.H.; Jung, J.; Lee, J.D.; Muninger, R.C.; Neef, W.S.; Sherwood, A.E.

1985-07-01

243

Characteristics of beryllium bonds; a QTAIM study.  

PubMed

The nature of beryllium bonds formed between BeX2 (X is H, F and Cl) and some Lewis bases have been investigated. The distribution of the Laplacian of electron density shows that there is a region of charge depletion around the Be atom, which, according to Laplacian complementary principal, can interact with a region of charge concentration of an atom in the base and form a beryllium bond. The molecular graphs of the investigated complexes indicate that beryllium in BeH2 and BeF2 can form beryllium bonds with O, N and P atoms but not with halogens. In addition, eight criteria based on QTAIM properties, including the values of electron density and its Laplacian at the BCP, penetration of beryllium and acceptor atom, charge, energy, volume and first atomic moment of beryllium atom, have been considered and compared with the corresponding ones in conventional hydrogen bonds. These bonds share many common features with very strong hydrogen bonds, however,some differences have also been observed. PMID:22286132

Eskandari, K

2012-08-01

244

Synthesis of lithium nitride for neutron production target of BNCT by in situ lithium deposition and ion implantation  

NASA Astrophysics Data System (ADS)

To achieve high performance of BNCT (Boron Neutron Capture Therapy) device, Li3N/Li/Pd/Cu four layered Li target was designed and the structures of the synthesized four layered target were characterized by X-ray photoelectron spectroscopy. For the purpose of avoiding the radiation blistering and lithium evaporation, in situ vacuum deposition and nitridation techniques were established for in situ production and repairing maintenance of the lithium target.Following conclusions were derived:Uniform lithium layer of a few hundreds nanometer was formed on Pd/Cu multilayer surface by in situ vacuum deposition technique using metallic lithium as a source material.Lithium nitrides were formed by in situ nitridation reaction by the implantation of low-energy nitrogen ions on the deposited lithium layer surface. The chemical states of the nitridated zone were close to the stoichiometric lithium nitride, Li3N.This nitridated zone formed on surface of four layered lithium target is stable for a long time in air condition. The in situ nitridation is effective to protect lithium target from degradation by unfavorable reactions.

Ishiyama, S.; Baba, Y.; Fujii, R.; Nakamura, M.; Imahori, Y.

2012-12-01

245

High-temperature cubic boron nitride p-n junction diode made at high pressure  

Microsoft Academic Search

A p-n junction diode of cubic boron nitride was made by growing an n-type crystal epitaxially on a p-type seed crystal at a pressure of 55 kilobars and a temperature of about 1700 C. A temperature-difference solvent method was used for the crystal growth, and beryllium and silicon were doped as acceptors and donors, respectively. Formation of the p-n junction

Osamu Mishima; Junzo Tanaka; Shinobu Yamaoka; Osamu Fukunaga

1987-01-01

246

Toxicological Studies on Beryllium and Oxides and Beryllium-Containing Exhaust Products.  

National Technical Information Service (NTIS)

Results of long-term studies on rats and rabbits, injected intratracheally with well-characterized key samples of beryllium oxide prepared by calcining beryllium hydroxide for 10 hours at 500, 1100 and 1600 C, respectively, show clearly that there is a de...

H. C. Spencer J. A. Blumenshine R. H. Hook S. B. McCollister S. E. Sadek

1968-01-01

247

Characterization of electrodeposited elemental boron  

Microsoft Academic Search

Elemental boron was produced through electrowinning from potassium fluoroborate dissolved in a mixture of molten potassium fluoride and potassium chloride. The characteristics of the electrodeposited boron (raw boron) as well as the water and acid-leached product (processed boron) were studied. The chemical purity, specific surface area, size distribution of particles and X-ray crystallite size of the boron powders were investigated.

Ashish Jain; S. Anthonysamy; K. Ananthasivan; R. Ranganathan; Vinit Mittal; S. V. Narasimhan; P. R. Vasudeva Rao

2008-01-01

248

Beryllium colorimetric detection for high speed monitoring of laboratory environments.  

PubMed

The health consequences of beryllium (Be2+) exposure can be severe. Beryllium is responsible for a debilitating and potentially fatal lung disease, chronic beryllium disease (CBD) resulting from inhalation of beryllium particles. The US Code of Federal Register (CFR), 10 CFR 850, has established a limit of 0.2 microg beryllium/100 cm(2) as the maximum amount of beryllium allowable on surfaces to be released from beryllium work areas in Department of Energy (DOE) facilities. The analytical technique described herein reduces the time and cost of detecting beryllium on laboratory working surfaces substantially. The technique provides a positive colorimetric response to the presence of beryllium on a 30.5 cm x 30.5 cm (1 ft(2)) surface at a minimum detection of 0.2 microg/100 cm(2). The method has been validated to provide positive results for beryllium in the presence of excess iron, calcium, magnesium, copper, nickel, chromium and lead at concentrations 100 times that of beryllium and aluminum and uranium (UO2(2+)) at lesser concentrations. The colorimetric detection technique has also been validated to effectively detect solid forms of beryllium including Be(OH)2, BeCl2, BeSO4, beryllium metal and BeO. PMID:12137989

Taylor, Tammy P; Sauer, Nancy N

2002-08-01

249

Introduction to Lithium Batteries.  

National Technical Information Service (NTIS)

Lithium batteries are being introduced into all three services in the Australian Defence Force. However, general information concerning lithium batteries is not available in a condensed form. This review examines various aspects of lithium batteries, incl...

W. N. Garrard

1988-01-01

250

Lithium-6: evolution from Big Bang to present  

NASA Astrophysics Data System (ADS)

The primordial abundances of deuterium, 4He, and 7Li are crucial to the determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). 6Li is only produced in tiny quantities and it is generally not considered to be a cosmological probe. However, recent major observational advances have produced an estimate of the 6Li/ 7Li ratio in a few very old stars in the galactic halo which impacts the question whether or not the lithium isotopes are depleted in the outer layers of halo stars, through proton induced reactions at the base of (or below) the convective zone. Here, we use (i) an empirical relation, independent of any evolutionary model, to set an upper limit on the 6Li rise compatible with the very existence of the Spite's plateau (i.e. the flat lithium abundance measured in very old stars of the halo of our Galaxy of different iron content) and (ii) a well founded evolutionary model of light elements based on spallation production ( Vangioni-Flam et al., 1997; Vangioni-Flam et al., 1998). Indeed, 6Li is a pure product of spallation through the major production reactions, fast oxygen and alphas interacting on interstellar H, He (especially in the early Galaxy). The rapid nuclei are both synthesized and accelerated by SN II. In this context, the 6Li evolution should go in step with that of beryllium and boron, recently observed by the Keck and HST telescopes. 6Li adds a new constraint on the early spallation in the Galaxy. In particular, if confirmed, the 6Li/ 9Be ratio observed in two halo stars (HD 84937, BD +263578 = HD 338529) gives strong boundary conditions on the composition and the spectrum of the rapid particles involved. Both methods converge to show that 6Li is essentially intact in halo stars, and a fortiori 7Li, which is more tightly bound. Moreover, extrapolating empirical and theoretical evolutionary curves to the very low metallicities, we can define a range of the 6Li abundance in the very early Galaxy consistent with Big Bang nucleosynthesis (5.610 -14 to 310 -13). Following the evolution at increasing metallicity, we explain the abundance in the solar system within a factor of about 2. The whole evolution from Big Bang to present is reasonably reproduced, which demonstrates the general consistency of the present analysis of 6Li. The baryonic density derived from both lithium isotopes is between 1.5 to 3.5% of the critical one, in good agreement with the determination based on independent analyses. Consequently, thanks to these new data and theoretical developments, we show that 6Li can be used to establish stellar 7Li abundances as a valid tracer due to the fact that it allows to reinforce the Spite's plateau as a primordial test of BBN; on the other hand, its early evolution can be used to corroborate the calculated BBN abundances. In the framework of this work, a pregalactic ?+ ? process producing 6Li is not necessary. Finally, thanks to 6Li, the physics of spallative production of light elements should be more easily mastered when more data will become available.

Vangioni-Flam, Elisabeth; Cass, Michel; Cayrel, Roger; Audouze, Jean; Spite, Monique; Spite, Franois

1999-07-01

251

Properties of boron/boron-nitride multilayers  

SciTech Connect

Boron-Nitride films are of interest for their high hardness and wear resistance. Large intrinsic stresses and poor adhesion which often accompany high hardness materials can be moderated through the use of a layered structure. Alternate layers of boron (B) and boron-nitride (BN) are formed by modulating the composition of the sputter gas during deposition from a pure B target. The thin films are characterized with TEM to evaluate the microstructure and with nanoindentation to determine hardness. Layer pair spacing and continuity effects on hardness are evaluated for the B/BN films.

Jankowski, A.F.; Wall, M.A.; Hayes, J.P. [Lawrence Livermore National Lab., CA (United States); Alexander, K.B. [Oak Ridge National Lab., TN (United States)

1996-06-01

252

Mirror matter can alleviate the cosmological lithium problem  

NASA Astrophysics Data System (ADS)

The abundance of lithium-7 confronts cosmology with a long lasting problem between the predictions of standard big bang nucleosynthesis and the baryonic density determined from the cosmic microwave background observations. This article investigates the influence of the existence of a mirror world, focusing on models in which neutrons can oscillate into mirror neutrons. Such a mechanism allows for an effective late time neutron injection, which induces an increase of the destruction of beryllium-7, due to an increase of the neutron capture, and then a decrease of the final lithium-7 abundance. Big bang nucleosynthesis sets constraints on the oscillation time between the two types of neutrons and the possibility for such a mechanism to solve, or alleviate, the lithium problem is emphasized.

Coc, Alain; Uzan, Jean-Philippe; Vangioni, Elisabeth

2013-06-01

253

Lithium literature review: lithium's properties and interactions  

SciTech Connect

The lithium literature has been reviewed to provide a better understanding of the effects of lithium spills that might occur in magnetic fusion energy (MFE) facilities. Lithium may be used as a breeding blanket and reactor coolant in these facilities. Physical and chemical properties of lithium as well as the chemical interactions of lithium with various gases, metals and non-metals have been identified. A preliminary assessment of lithium-concrete reactions has been completed using differential thermal analysis. Suggestions are given for future studies in areas where literature is lacking or limited.

Jeppson, D.W.; Ballif, J.L.; Yuan, W.W.; Chou, B.E.

1978-04-01

254

A new class of electrochemically and thermally stable lithium salts for lithium battery electrolytes. 1: Synthesis and properties of lithium bis[1,2-benzenediolato(2-)-O,O]borate  

Microsoft Academic Search

Disclosed is a new class of nontoxic thermally, chemically, and electrochemically stable, inexpensive lithium salts based on a chelate complex anion of boron with aromatic or aliphatic diols or carboxylic acids. The synthesis, purification and analysis of the first member of this class, lithium bis[1,2-benzenediolato(2-)-O,O]borate (Li[B(CHO)]) is described and some results are given from electrochemical experiments of its solution in

J. Barthel; M. Wuehr; R. Buestrich; H. J. Gores

1995-01-01

255

Berilio. Sus minerales. Pte. 1. (Beryllium. Its minerals. Pt. 1).  

National Technical Information Service (NTIS)

With this work a series of reports begins, under the generic name 'Beryllium', related to several aspects of beryllium technology. The target is to update, with critical sense, current bibliographic material in order to be used in further applications. So...

O. A. Lires C. A. Delfino J. Botbol

1990-01-01

256

Design and producibility of precision beryllium structures for spacecraft applications  

NASA Astrophysics Data System (ADS)

Basic design guidelines for beryllium precision structures are discussed and a thorough presentation is given on the design evolution of the RGA integrating structure for ESA's XMM Mission. Beryllium producibility issues, manufacturing flowcharts and flight heritage data is reviewed.

Hardesty, Robert E.; Decker, Todd A.

1995-10-01

257

Demonstration of the Presence of Beryllium in Pulmonary Granulomas.  

National Technical Information Service (NTIS)

Chronic beryllium disease was induced experimentally in dogs, and the presence of beryllium was demonstrated in specific histologic structures (pulmonary granulomas) by means of a laser microprobe and emission spectroscopy. The ability to detect minute am...

J. R. Prine S. F. Brokeshoulder D. E. McVean F. R. Robinson

1965-01-01

258

Boron-Doped Nanocrystalline Diamond.  

National Technical Information Service (NTIS)

A conductive boron doped nanocrystalline diamond is described. The boron doped diamond has a conductivity which uses the boron in the crystals as a charge carrier. The diamond is particularly useful for electrochemical electrodes in oxidation-reduction re...

G. M. Swain M. Witek P. Sonthalia Y. Show

2004-01-01

259

Berylliumcopper reactivity in an ITER joining environment  

Microsoft Academic Search

Berylliumcopper reactivity was studied using test parameters being considered for use in the ITER reactor. In this application, berylliumcopper tiles are produced using a low-temperature coppercopper diffusion bonding technique. Beryllium is joined to copper by first plating the beryllium with copper followed by diffusion bonding the electrodeposited (ED) copper to a wrought copper alloy (CuNiBe) at 450C, 13 h using

B. C. Odegard; C. H. Cadden; N. Y. C. Yang

1998-01-01

260

Major histocompatibility locus genetic markers of beryllium sensitization and disease  

Microsoft Academic Search

Major histocompatibility locus genetic markers of beryllium sensitization and disease. C. Saltini, L. Richeldi, M. Losi, M. Amicosante, C. Voorter, E. van den Berg-Loonen, R.A. Dweik, H.P. Wiedemann, D.C. Deubner, C. Tinelli. #ERS Journals Ltd 2001. ABSTRACT: Hypersensitivity to beryllium (Be) is found in 1-16% of exposed workers undergoing immunological screening for beryllium disease using the beryllium lym- phocyte proliferation

C. Saltini; L. Richeldi; M. Losi; M. Amicosante; C. Voorter; E. Van Den Berg-Loonen; R. A. Dweik; H. P. Wiedemann; D. C. Deubner; C. Tinelli

2001-01-01

261

Thermal Conductivity of Composites of Beryllia and Lithium Titanate  

NASA Astrophysics Data System (ADS)

The International Thermonuclear Experimental Reactor (ITER) is designed to demonstrate the scientific and technological feasibility of fusion power for energy purposes. Wide varieties of solid breeders and multiplier materials have been proposed for fusion blankets. Beryllium and lithium titanate (Li2TiO3) have been accepted as neutron multiplier and breeder materials, respectively. However, swelling of beryllium due to helium and tritium permeation through metallic beryllium and low thermal conductivity of lithium titanate have caused serious limitations when ITER is in the demo version. It has been well established that BeO due its highest thermal conductivity among the known ceramics, low neutron absorption cross section, and high neutron reflection cross section is a good neutron multiplier. In the present investigation, a novel ceramic single compound of BeO-Li2TiO3 was synthesized, keeping the BeO content to Li2TiO3 in the volume ratio of 80:20, 75:25, 65:35, and 55:45 with the aim of maintaining the tritium breeding ratio as more than one, and characterized for phases present by x-ray diffraction and scanning electron microscopy.

Rath, B. N.; Ghanwat, S. J.; Kaity, Santu; Danani, Chandan; Kulkarni, R. V.; Alur, V. D.; Sathiyamoorthy, D.; Anantharaman, S.

2013-05-01

262

Results from the CDX-U Lithium Wall and NSTX Lithium Pallet Injection and Evaporation Experiments  

SciTech Connect

CDX-U has been operated with the vacuum vessel wall and limiter surfaces nearly completely coated with lithium, producing dramatic improvements to plasma performance. Discharges achieved global energy confinement times up to 6 ms, exceeding previous CDX-U results by a factor of 5, and ITER98P(y,1) scaling by 2-3. Lithium wall coatings up to 1000 {angstrom} thick were applied between discharges by electron-beam-induced evaporation of a lithium-filled limiter and vapor deposition from a resistively heated oven. The e-beam power was modest (1.6 kW) but it produced up to 60 MW/m2 power density in a 0.3 cm{sup 2} spot; the duration was up to 300 s. Convective transport of heat away from the beam spot was so effective that the entire lithium inventory (140 g) was heated to evaporation (400-500 C) and there was no observable hot spot on the lithium surface within the beam footprint. These results are promising for use of lithium plasma-facing components in reactor scale devices. Lithium coating has also been applied to NSTX carbon plasma-facing surfaces, to control the density rise during long-duration H-modes for non-inductive current sustainment. First, lithium pellets were injected into sequences of Ohmically heated helium plasmas in both center stack limiter (CSL) and lower single-null divertor (LSND) configurations to deposit a total of 25-30 mg of lithium on the respective plasma contact areas. In both cases, the first subsequent L mode, deuterium discharge with NBI showed a reduction in the volume-average density by a factor {approx}3 compared to similar discharges before the lithium coating. Recently, a lithium evaporator was installed aimed toward the graphite tiles of the lower center stack and divertor. Twelve depositions, ranging from about 10 mg to 5 g of lithium, were performed. The effects on LSND L-mode, double-null divertor (DND) H-mode, and DND reversed-shear plasmas were variable but, immediately after coating, there were decreases in the density and significant increases in electron and ion temperature, neutron rate, confinement time, and edge flow velocity, and reductions in H-mode ELM frequency. For several days of operation after lithium coating, the ratio of oxygen to carbon emission was lower than with boronization.

Majeski, R; Kugel, H; Bell, M; Bell, R; Beiersdorfer, P; Bush, C; Doerner, R; Gates, D; Gray, T; Kaita, R; LeBlanc, B; Maingi, R; Mansfield, D; Menard, J; Mueller, D; Paul, S; Raman, R; Roquemore, A; Skinner, C; Sabbagh, S; Souskhanovskii, V; Spaleta, J; Stevenson, T; Timberlake, J; Zakharov, L

2006-10-05

263

Simulating the FTICR-MS signal of a decaying beryllium-7 ion plasma in a two-dimensional electrostatic PIC code  

Microsoft Academic Search

Beryllium-7 (Be-7) only decays by electron capture into lithium-7 (Li-7) with a half life of 53 days. We study the effect of ionization on this decay rate. We do so by trapping a Be-7 ion plasma in a cylindrical Malmberg-Penning trap and measuring Be-7 and Li-7 concentrations as functions of time by using Fourier transform ion cyclotron resonance mass spectrometry

Michael Takeshi Nakata

2010-01-01

264

BERYLLIUM COMPOSITE STRUCTURES. VOLUME II. MATERIALS AND PROCESSES  

Microsoft Academic Search

Methods developed for the fabrication of beryllium sheet composite ; structures are given. Descriptions and performance evaluation are included for a ; variety of beryllium load bearing panels and porous ceramic heat shields ; developed to withstand temperatures in excess of 3000 deg F. Concepts are ; outiined defining application of berylliumceramic composites to aerospace vehicle ; structures. Beryllium sheet

J. N. Krusos; A. S. Kjelby; J. Borosic; T. J. Byrne

1962-01-01

265

REVIEWS OF THE ENVIRONMENTAL EFFECTS OF POLLUTANTS: VI. BERYLLIUM  

EPA Science Inventory

The report is a review of the scientific literature on the biological and environmental effects of beryllium. Included in the review are a general summary and a comprehensive discussion of the following topics as related to beryllium and specific beryllium compounds: physical and...

266

Introduction to Beryllium: Uses, Regulatory History, and Disease  

Microsoft Academic Search

Beryllium is an ubiquitous element in the environment, and it has many commercial applications. Because of its strength, electrical and thermal conductivity, corrosion resistance, and nuclear properties, beryllium products are used in the aerospace, automotive, energy, medical, and electronics industries. What eventually came to be known as chronic beryllium disease (CBD) was first identified in the 1940s, when a cluster

Marc E. Kolanz

2001-01-01

267

Direct Drive Beryllium Ablator Capsules for the Omega Laser  

Microsoft Academic Search

We are designing direct drive beryllium ablator capsules for the Omega laser as part of our effort to develop beryllium ablator ignition capsules for the National Ignition Facility (NIF). The main goals for this experimental campaign is to develop the fabrication expertise for roughly NIF size capsules and obtain experimental data on how the copper- brazed joint between the beryllium

P. A. Bradley; D. C. Wilson; J. A. Cobble; T. J. Murphy; J. C. Cooley; M. A. Salazar; G. Rivera Nobile Jr.

2001-01-01

268

Mechanisms controlling graphite furnace atomization and stabilization of beryllium  

Microsoft Academic Search

The real-time mass spectra of gas-phase species, produced in a graphite furnace containing beryllium analyte and a magnesium modifier, are obtained and used to elucidate mechanisms that control vaporization, atomization and stabilization. It is determined that free beryllium is produced from the thermal decomposition of adsorbed monomeric oxide. Beryllium is lost as polymeric oxides, carbides, cyanide, and cyanamide during the

D. L. Styris; D. A. Redfield

1987-01-01

269

Chronic beryllium disease: Diagnosis and management  

SciTech Connect

Chronic beryllium disease is predominantly a pulmonary granulomatosis that was originally described in 1946. Symptoms usually include dyspnea and cough. Fever, anorexia, and weight loss are common. Skin lesions are the most common extrathoracic manifestation. Granulomatous hepatitis, hypercalcemia, and kidney stones can also occur. Radiographic and physiologic abnormalities are similar to those in sarcoidosis. While traditionally the pathologic changes included granulomas and cellular interstitial changes, the hallmark of the disease today is the well-formed granuloma. Immunologic studies have demonstrated a cell-mediated response to beryllium that is due to an accumulation of CD4{sup +} T cells at the site of disease activity. Diagnosis depends on the demonstration of pathologic changes (i.e., granuloma) and evidence that the granuloma was caused by a hypersensitivity to beryllium (i.e., positive lung proliferative response to beryllium). Using these criteria, the diagnosis of chronic beryllium disease can now be made before the onset of clinical symptoms. Whether, with early diagnosis, the natural course of this condition will be the same as when it was traditionally diagnosed is not known. Currently, corticosteroids are used to treat patients with significant symptoms or evidence of progressive disease. 21 refs.

Rossman, M.D. [Hospital of the Univ. of Pennsylvania, Philadelphia, PA (United States)

1996-10-01

270

Lithium Ion Conductivity in Lithium Nitride.  

National Technical Information Service (NTIS)

The ionic conductivity of polycrystalline lithium nitride has been determined using ac techniques and complex plane analysis. The ionic conductivity is quite high, so that this material may be an interesting lithium-conducting solid electrolyte. (Author)

B. A. Boukamp R. A. Huggins

1976-01-01

271

[Chronic Beryllium disease after exposure to low-beryllium-content copper].  

PubMed

A 24-year-old man was admitted to our hospital because of exertional dyspnea and abnormal shadows on chest X-ray film. He worked in a factory, where he was exposed to 1.8% beryllium-copper alloys. His job was to draw out heated beryllium-copper wire to make it more fine. Chest X-ray film and chest CT scan showed left-sided pneumothorax, diffuse fine reticulonodular shadows, and several cysts. Pulmonary-function tests showed a restrictive disorder and a low diffusing capacity. A specimen obtained by open-lung biopsy showed epithelioid cell granuloma and alveolitis, which were compatible with chronic beryllium disease. The beryllium content of the lung tissue was 0.045 microgram/gram. Beryllium lymphocyte transformation tests on blood and on bronchoalveolar lavage fluid were positive. Based on these findings, chronic beryllium disease was diagnosed. After treatment with 1 mg/kg of prednisolone daily, dyspnea disappeared. Then the dose was tapered slowly. In Japan, chronic beryllium disease is extremely rare, and to our knowledge only 22 other cases have been reported. PMID:8544383

Hasejima, N; Kobayashi, H; Takezawa, S; Yamato, K; Kadoyama, C; Kawano, Y

1995-10-01

272

Fabrication of boron articles  

DOEpatents

This invention is directed to the fabrication of boron articles by a powder metallurgical method wherein the articles are of a density close to the theoretical density of boron and are essentially crackfree. The method comprises the steps of admixing 1 to 10 weight percent carbon powder with amorphous boron powder, cold pressing the mixture and then hot pressing the cold pressed compact into the desired article. The addition of the carbon to the mixture provides a pressing aid for inhibiting the cracking of the hot pressed article and is of a concentration less than that which would cause the articles to possess significant concentrations of boron carbide.

Benton, Samuel T. (Knoxville, TN)

1976-01-01

273

Berilio. Evaluacion de procesos industriales para la produccion del hidroxido. Pte. 3. (Beryllium. Evaluation of beryllium hydroxide industrial processes. Pt. 3).  

National Technical Information Service (NTIS)

This work continues the 'Beryllium' series. It is a historical review of different industrial processes of beryllium hydroxide obtention from beryllium ores. Flowsheats and operative parameters of five plants are provided. These plants (Degussa, Brush Ber...

O. A. Lires C. A. Delfino J. Botbol

1991-01-01

274

The Search for Rydberg Matter: Beryllium  

SciTech Connect

Results are presented from theoretical investigations of condensed excited states of beryllium by the Hartree-Fock method with allowance for the width of the atomic levels. It is shown that, during the excitation of a beryllium atom in the X-ray energy range, the 2p states split, the one-electron energy levels are shifted by unequal amounts, the 2s and 2p states mix at excitation energies of 10 and 14 Ry, and the atom is stabilized at energies higher than 6.7 Ry. In the optical range of excitation energies, a condensed excited state of beryllium with a lifetime on the order of 0.1 fs is reveale000.

Popov, A.V. [Altai State University, ul. Dimitrova 66, Barnaul, 656099 (Russian Federation)

2005-03-15

275

Lithium plasma-facing components in CDX-U  

NASA Astrophysics Data System (ADS)

Investigations into the use of liquid lithium as a plasma facing component have begun in the CDX-U spherical tokamak at the Princeton Plasma Physics Laboratory. The first experiments employed a lithium-coated rail limiter geometry, in a system designed and built by the PISCES group at UCSD. Little difference was seen in tokamak discharges with the lithium rail limiter, versus operation with a more conventional boron carbide limiter. Recently a large area (2,000 cm^2) toroidal tray limiter has been commissioned, and initial results of plasma operations with the tray system will be presented. Upgrades to diagnostic, fueling, ohmic, plasma startup, and auxiliary heating systems designed to support the lithium program will also be described.

Majeski, R.; Kaita, R.; Boaz, M.; Efthimion, P.; Hoffman, D.; Jones, B.; Kugel, H.; Munsat, T.; Post-Zwicker, A.; Raftopoulos, S.; Schmidt, G. L.; Soukhanovskii, V.; Spaleta, J.; Taylor, G.; Timberlake, J.; Finkenthal, M.; Stutman, D.; Antar, G.; Doerner, R.; Luckhardt, S.; Seraydarian, R. P.; Conn, R. W.; Maingi, R.; Causey, R.; Buchenauer, D.; Ulrickson, M.; Maiorano, M.; Smith, S.; Miller, B.

2001-10-01

276

Alloying of aluminum-beryllium alloys  

NASA Astrophysics Data System (ADS)

The existing phase diagrams of Al-Be- X alloys, where X is an alloying element, are analyzed. Element X is noted to poorly dissolve in both aluminum and beryllium. It is shown that the absence of intermetallic compounds in the Al-Be system affects the phase equilibria in an Al-Be- X system. Possible phase equilibria involving phases based on aluminum, beryllium, and intermetallic compounds are proposed, and the types of strengthening of Al-Be alloys by an addition of a third element are classified.

Molchanova, L. V.; Ilyushin, V. N.

2013-01-01

277

Beryllium window for synchrotron light sources  

SciTech Connect

As part of an on-going upgrade program at the National Synchrotron Light Source, a parametric study of rectangular flat and curved beryllium windows of varying thickness and heights and under varying thermal loading was undertaken. The study consisted of a series of 2D and 3D thermal stress finite element analyses to determine the relative benefit of various combinations of parameters with respect to the windows` ability to withstand thermal loads. This study includes evaluation of fixed versus flexible mounting of flat and curved beryllium windows. Buckling analyses for both types of mountings are also included.

Lynch, D.R.; Berman, L.; Montanez, P.; Pjerov, S.; Stefan, P.; Woodle, M.

1996-10-01

278

Magnetron sputter deposition of boron and boron carbide  

Microsoft Academic Search

The fabrication of x-ray optical coatings with greater reflectivity required the development of sputter deposition processes for boron and boron carbide. The use of high density boron and boron carbide and a vacuum brazed target design was required to achieve the required sputter process stability and resistance to the thermal stress created by high rate sputtering. The results include a

M. A. McKernan; D. Makowiecki; P. Ramsey; A. Jankowski

1991-01-01

279

High-temperature properties of lithium tetraborate Li2B4O7  

NASA Astrophysics Data System (ADS)

High-temperature coherent neutron powder diffraction experiments were carried out on Li2B4O7 with boron isotope ratio 11B?:?10B as high as 99.6?:?0.4%. Neither traces of phase transformations nor discontinuous changes of physical properties were observed. Anomalies in the thermal expansion of lithium tetraborate were considered in terms of first-order Grneisen approximation. Extended bond length analysis revealed significant modifications of the boron-oxygen framework which is supplemented by dynamic lithium disorder. Impedance spectroscopy studies revealed a complicated conduction mechanism in single crystalline lithium tetraborate. The lithium diffusion pathway for bulk conductivity along the polar axis was established using both maximum entropy and anharmonic refinement techniques.

Senyshyn, A.; Boysen, H.; Niewa, R.; Banys, J.; Kinka, M.; Burak, Ya; Adamiv, V.; Izumi, F.; Chumak, I.; Fuess, H.

2012-05-01

280

Minerals Yearbook 1989: Lithium  

SciTech Connect

The United States led the world in lithium mineral and compound production and consumption. Estimated consumption increased slightly, and world production also grew. Sales increased for domestic producers, who announced price increases for the third consecutive year. Because lithium is electrochemically reactive and has other unique properties, there are many commercial lithium products. Producers sold lithium as mineral concentrate, brine, compound, or metal, depending upon the end use. Most lithium compounds were consumed in the production of ceramics, glass, and primary aluminum.

Ober, J.A.

1989-01-01

281

Minerals Yearbook 1989: Boron  

Microsoft Academic Search

U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California was the only domestic source of boron minerals. The United States continued to provide essentially all of its own supply while maintaining a strong position

Lyday

1990-01-01

282

Boron doped graphene nanoribbons  

Microsoft Academic Search

We will present a detailed study of the electronic, magnetic and transport properties of boron doped graphene nanoribbons, for various widths. The electronic structures and the equilibrium geometries were obtained through ab initio total energy DFT calculations. The transport properties were investigated using nonequilibrium Green's functions. Our results reveal that the substitutional boron atoms occupy the edge sites of nanoribbons,

Thiago Martins; Hiroki Miwa; Antonio J. R. da Silva; A. Fazzio

2007-01-01

283

ELECTROLYTIC PRODUCTION OF BORON  

Microsoft Academic Search

Elemental boron was produced by the fused salt electrolysis of potassium ; fluoborate. A study was made of anode and cathode materials of construction, ; particularly the effect of various grades of graphite as anode material. The ; effect of additives to the electrolyte (including potassium, aluminum, calcium, ; vanadium, nickel, Inconel, water, and sulfate ion) on boron yield and

George T. Miller

1959-01-01

284

Boron in the Environment  

Microsoft Academic Search

Boron has recently come to the attention of the U.S. Environmental Protection Agency as a possible contaminant worthy of regulation, but questions must still be addressed before a regulatory determination can take place. This article reviews current knowledge about boron as it pertains to water treatment and the environment so that informed decisions can be made regarding regulations and direction

JEFFREY L. PARKS; MARC EDWARDS

2005-01-01

285

Magnetron sputtered boron films  

DOEpatents

A method is described for the production of thin boron and titanium/boron films by magnetron sputter deposition. The amorphous boron films contain no morphological growth features, unlike those found when thin films are prepared by various physical vapor deposition processes. Magnetron sputter deposition method requires the use of a high density crystalline boron sputter target which is prepared by hot isostatic pressing. Thin boron films prepared by this method are useful for producing hardened surfaces, surfacing machine tools, etc. and for ultra-thin band pass filters as well as the low Z element in low Z/high Z optical components, such as mirrors which enhance reflectivity from grazing to normal incidence. 8 figs.

Makowiecki, D.M.; Jankowski, A.F.

1998-06-16

286

Magnetron sputtered boron films  

DOEpatents

A method is described for the production of thin boron and titanium/boron films by magnetron sputter deposition. The amorphous boron films contain no morphological growth features, unlike those found when thin films are prepared by various physical vapor deposition processes. Magnetron sputter deposition method requires the use of a high density crystalline boron sputter target which is prepared by hot isostatic pressing. Thin boron films prepared by this method are useful for producing hardened surfaces, surfacing machine tools, etc. and for ultra-thin band pass filters as well as the low Z element in low Z/high Z optical components, such as mirrors which enhance reflectivity from grazing to normal incidence.

Makowiecki, Daniel M. (Livermore, CA); Jankowski, Alan F. (Livermore, CA)

1998-01-01

287

Microwave sintering of boron carbide  

DOEpatents

A method for forming boron carbide into a particular shape and densifying the green boron carbide shape. Boron carbide in powder form is pressed into a green shape and then sintered, using a microwave oven, to obtain a dense boron carbide body. Densities of greater than 95% of theoretical density have been obtained. 1 tab.

Blake, R.D.; Katz, J.D.; Petrovic, J.J.; Sheinberg, H.

1988-06-10

288

Solvent removal of beryllium from surfaces of equipment made of beryllium copper.  

PubMed

Exposure to beryllium compounds, both by inhalation and skin contact, may result in immune sensitization and chronic beryllium disease. The objective of the present research work was to study the feasibility of removing beryllium compounds from the surfaces of devices made of Be-Cu alloy and to estimate the frequency at which the surfaces had to be rubbed in order to evaluate the likelihood that beryllium can be removed from the surfaces by serial wipe sampling at concentrations exceeding the US Department of Energy (DOE) standard limit of 0.2 microg per 100 cm2. The standard limit was exceeded after successive cleanings of moulds and plates made of Be-Cu alloy with solvents such Citranox, an acidic solvent, Alconox, Z-99 and Fantastik, basic solvents, or more neutral solvents such as Luminox and water. Citranox was the best solvent for extracting beryllium from the tested surfaces, while Alconox seemed to be the second best one. In general, warm water, Luminox and Z-99 seemed to be less efficient for extracting Be from all equipment. The results of the present study suggest that Ghost Wipes, when passed across a surface under the firm pressure of an individual's hand, can be used to detect beryllium contamination. However, they seem to show low reliability for quantification. From a safety standpoint in occupational settings, workers should be offered skin protection and respiratory protection if they have to handle devices made of Be-Cu alloy. PMID:19254960

Dufresne, A; Turcotte, V; Golshahi, H; Viau, S; Perrault, G; Dion, C

2009-03-02

289

Risks of beryllium disease related to work processes at a metal, alloy, and oxide production plant  

Microsoft Academic Search

OBJECTIVES: To describe relative hazards in sectors of the beryllium industry, risk factors of beryllium disease and sensitisation related to work process were sought in a beryllium manufacturing plant producing pure metal, oxide, alloys, and ceramics. METHODS: All 646 active employees were interviewed; beryllium sensitisation was ascertained with the beryllium lymphocyte proliferation blood test on 627 employees; clinical evaluation and

K Kreiss; M M Mroz; B Zhen; H Wiedemann; B Barna

1997-01-01

290

Beryllium Materials for National Ignition Facility Targets LDRD Final Report  

SciTech Connect

The National Ignition Facility (NIF) will require spherical ignition capsules approximately 2 mm in diameter with a 120- to 150-pm-thick ablator. Beryllium-based alloys are promising candidates for an ablator material due to their combination of low opacity and relatively high density (compared to polymer coatings). For optimum performance, the Be-coated capsules require a smooth surface finish, uniform thickness, microscopic homogeneity, and preferably high strength. The coatings must contain on the order of 1 at.% of a high-Z dopant (such as Cu) and permit the capsule to be filled with fuel, which will be a mixture of hydrogen isotopes. These demanding requirements can be met through a synthesis method with a focus on the control of microstructure. In our experiments, the sputter deposition process has been manipulated so as to decrease the grain size, thereby reducing roughness and improving homogeneity. The material properties of sputter-deposited coatings are sensitive to their microstructure and growth morphology. To meet the requirements for Be coated capsules, the goal of this project was to optimize the microstructure and growth morphology through the control of deposition process parameters. Prior experimental studies of evaporation and sputter deposition revealed that the grain size of 99.8 at.% pure Be can be reduced by adding insoluble metal impurities such as Fe or Ti. These higher atomic weight elements can replace the requirement of adding 1 at.% Cu to the Be. Grain size can also be reduced by using additives that are metallic-glass formers, such as boron. Finally, the microstructure can be modified by changing the energy or angular distribution of the depositing flux. Our initial experiments focused on the development of Be-B-X alloys, where X is Fe and/or Cu. This work was successful in reducing the grain size of coatings deposited on planar substrates from microns to at least nanometers. TEM cross sections of these films showed no discernible grain structure, so for the purposes of this project the material was a glass. Deposition of a few pm of this alloy onto stationary capsules produced extremely smooth films: rms roughnesses of about 1 nm were observed using atomic force microscopy. As the coating thickness was increased, however, intrinsic stress in the film became a serious problem. Buckling and delamination were the typical symptoms of this phenomenon. Although there are techniques for mitigating stress build-up in deposited films, we concluded it would pose a formidable problem for the very thick coatings required for NIF capsules. For this reason, we shifted our efforts away from glassy alloys and concentrated on modifying the energy and angular distribution of the depositing Cu-doped beryllium flux.

McEachern, R L

2001-02-27

291

Beryllium derivatives of a phenyl-substituted ?-diketiminate: a well-defined ring opening reaction of tetrahydrofuran.  

PubMed

The phenyl-substituted ?-diketiminate ligand precursor (Ph)LH, [(Dipp)NC(Ph)CHC(Ph)NH(Dipp)] (Dipp = 2,6-di-isopropylphenyl) and its lithium and beryllium halide derivatives [(Ph)LLi(OEt2)], [(Ph)LBeCl] and [(Ph)LBeI] have been synthesised and characterised by NMR and X-ray structural analysis. The iodoberyllium complex [(Ph)LBeI] reacts with THF in a well-defined ring-opening insertion reaction to form the 4-iodo-n-butoxide complex [(Ph)LBeO(CH2)4I]. PMID:23685744

Arrowsmith, Merle; Crimmin, Mark R; Hill, Michael S; Kociok-Khn, Gabriele

2013-05-17

292

Energy levels for Be-7 (Beryllium-7)  

NASA Astrophysics Data System (ADS)

This document is part of Subvolume C `Tables of Excitations of Proton- and Neutron-rich Unstable Nuclei' of Volume 19 `Nuclear States from Charged Particle Reactions' of Landolt-Brnstein - Group I `Elementary Particles, Nuclei and Atoms'. It provides energy levels for atomic nuclei of the isotope Be-7 (beryllium, atomic number Z = 4, mass number A = 7).

Sukhoruchkin, S. I.; Soroko, Z. N.

293

Neutron Resonance Parameters for Be-7 (Beryllium)  

NASA Astrophysics Data System (ADS)

This document is part of the Supplement containing the complete sets of data of Volume 24 `Neutron Resonance Parameters' of Landolt-Brnstein - Group I `Elementary Particles, Nuclei and Atoms'. It provides the neutron resonance parameters for the isotope Be-7 (Beryllium).

Sukhoruchkin, S. I.; Soroko, Z. N.

294

THE BERYLLIUM CONTENT OF SOME METEORITES  

Microsoft Academic Search

The beryllium concentration of 17 meteorites was determined with ; excellent precision by a fluorometric procedure using morin as reagent. The ; average concentration found for 13 chondrites and 1 achondrite was 0.038 ppm or ; 0.64 atom per 10⁶ atoms of silicon. Two other achondrites were excluded ; from the average because of their large deviations from the mean.

C. W. Sill; C. P. Willis

1962-01-01

295

Genetic/Exposure Interaction in Beryllium Disease.  

National Technical Information Service (NTIS)

CBD is a hypersensitivity granulomatous disease affecting the lungs of people exposed to the metal Beryllium (Be2+). Objective: To study the polymorphisms of the HLA class II molecules that influence whether an individual will develop CBD and/or BeS in a ...

C. Rice D. Monos K. D. Rosenman M. Rossman V. S. Hertzberg

2008-01-01

296

Summary of beryllium specifications, current and historical  

SciTech Connect

This report summarizes beryllium properties included in producer, Department of Energy, and government specifications. The specifications are divided into two major categories: current and historical. Within each category the data are arranged primarily according to increasing purity and secondarily by increasing tensile properties. Qualitative comments on formability and weldability are included. Also, short summaries of powder production and consolidation techniques are provided.

Abeln, S.P.; Kyed, P.

1990-12-28

297

Chronic beryllium disease: Diagnosis and management  

Microsoft Academic Search

Chronic beryllium disease is predominantly a pulmonary granulomatosis that was originally described in 1946. Symptoms usually include dyspnea and cough. Fever, anorexia, and weight loss are common. Skin lesions are the most common extrathoracic manifestation. Granulomatous hepatitis, hypercalcemia, and kidney stones can also occur. Radiographic and physiologic abnormalities are similar to those in sarcoidosis. While traditionally the pathologic changes included

Rossman

1996-01-01

298

Lithium Ion Conductive Electrolyte Composition.  

National Technical Information Service (NTIS)

A solid electrolyte for the lithium family of batteries is proposed which has a high lithium ion conductivity. It comprises a solid solution of lithium sulfate and lithium hydroxide. 3 figures. (ERA citation 02:048856)

H. Ikeda S. Narukawa

1977-01-01

299

Historical analysis of airborne beryllium concentrations at a copper beryllium machining facility (1964-2000).  

PubMed

Copper beryllium alloys are the most commonly used form of beryllium; however, there have been few studies assessing occupational exposure in facilities that worked exclusively with this alloy versus those where pure metal or beryllium oxide may also have been present. In this paper, we evaluated the airborne beryllium concentrations at a machining plant using historical industrial hygiene samples collected between 1964 and 2000. With the exception of a few projects conducted in the 1960s, it is believed that >95% of the operations used copper beryllium alloy exclusively. Long-term (>120 min) and short-term (<120 min) personal and area samples were collected during a variety of activities including machining of copper beryllium-containing parts, as well as finishing operations (e.g., deburring and polishing) and decontamination of machinery. A total of 580 beryllium air samples were analyzed (311 personal and 269 area samples). The average concentration based on area samples (1964-2000) was 0.021 microg m(-3) (SD 0.17 microg m(-3); range 0.00012-2.5 microg m(-3)); 68.8% were below the analytical limit of detection (LOD). The average airborne beryllium concentration, based on all personal samples available from 1964 through the end of 2000 (n = 311), was 0.026 microg m(-3) (SD 0.059 microg m(-3); range 0.019-0.8 microg m(-3)); 97.4% were below the LOD. Personal samples collected from machinists (n = 78) had an average airborne concentration of 0.021 microg m(-3) (SD 0.014 microg m(-3); range 0.019-0.14 microg m(-3)); 97.4% were below the LOD. Airborne concentrations were consistently below the Occupational Safety and Health Administration permissible exposure limit for beryllium (2 microg m(-3)). Overall, the data indicate that for machining operations involving copper beryllium, the airborne concentrations for >95% of the samples were below the contemporaneous occupational exposure limits or the 1999 Department of Energy action level of 0.2 microg m(-3) and, in most cases, were below the LOD. PMID:19383942

McAtee, B L; Donovan, E P; Gaffney, S H; Frede, W; Knutsen, J S; Paustenbach, D J

2009-04-21

300

Control of beryllium powder at a DOE facility  

SciTech Connect

Beryllium is contained in a number of domestic and national defense items. Although many items might contain beryllium in some manner, few people need worry about the adverse effects caused by exposure to beryllium because it is the inhalable form of beryllium that is most toxic. Chronic beryllium disease (CBD), a granulomas and fibrotic lung disease with long latency, can be developed after inhalation exposures to beryllium. It is a progressive, debilitating lung disease. Its occurrence in those exposed to beryllium has been difficult to predict because some people seem to react to low concentration exposures whereas others do not react to high concentration exposures. Onset of the disease frequently occurs between 15 to 20 years after exposure begins. Some people develop the disease after many years of low concentration exposures but others do not develop CBD even though beryllium is shown to be present in lungs and urine. Conclusions based on these experiences are that their is some immunological dependence of developing CBD in about 3--4% of the exposed population, but the exact mechanism involved has not yet been identified. Acute beryllium disease can occur after a single exposure to a concentration of greater than 0.100 mg/m3 (inhalation exposure); it is characterized by the development of chemical pneumoconiosis, a respiratory disease. The acute effect of skin contact is a dermatitis characterized by itching and reddened, elevated, or fluid-accumulated lesions which appear particularly on the exposed surfaces of the body, especially the face, neck, arms, and hands. Small particles of beryllium that enter breaks in the skin can lead to the development of granulomas and/or open sores that do not heal until the beryllium has been removed. Our interest is only airborne beryllium, which is found in areas that machine or produce beryllium.

Langner, G.C.; Creek, K.L.; Castro, R.G.

1997-12-31

301

Beryllium contamination inside vehicles of machine shop workers  

SciTech Connect

Inhalation of beryllium particles causes a chronic, debilitating lung disease--chronic beryllium disease (CBD)--in immunologically sensitized workers. Evidence that very low concentrations of beryllium may initiate this chronic disease is provided by incidences of the illness in family members exposed to beryllium dust from workers` clothes and residents in neighborhoods surrounding beryllium refineries. This article describes the results of a cross-sectional survey to evaluate potential take-home beryllium exposures by measuring surface concentrations on the hands and in vehicles of workers at a precision machine shop where cases of CBD had recently been diagnosed. Many workers did not change out of their work clothes and shoes at the end of their shift, increasing the risk of taking beryllium home to their families. Wipe samples collected from workers` hands and vehicle surfaces were analyzed for beryllium content by inductively coupled argon plasma-atomic emission spectroscopy (ICP-AES). The results ranged widely, from nondetectable to 40 {micro}g/ft{sup 2} on workers` hands and up to 714 {micro}g/fg{sup 2} inside their vehicles, demonstrating that many workers carried residual beryllium on their hands and contaminated the inside of their vehicles when leaving work. The highest beryllium concentrations inside the workers` vehicles were found on the drivers` floor (GM = 19 {micro}g/ft{sup 2}, GSD = 4.9), indicating that workers were carrying beryllium on their shoes into their vehicles. A safe level of beryllium contamination on surfaces is not known, but it is prudent to reduce the potential for workers to carry beryllium away from the work site.

Sanderson, W.T. [National Inst. for Occupational Safety and Health, Cincinnati, OH (United States). Div. of Surveillance, Hazard Evaluations, and Field Studies; Henneberger, P.K. [National Inst. for Occupational Safety and Health, Morgantown, WV (United States). Div. of Respiratory Disease Studies; Martyny, J. [Tri-County Health Dept., Commerce, CO (United States); Ellis, K. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Environmental Health; Mroz, M.M. [National Jewish Medical and Research Center, Denver, CO (United States); Newman, L.S. [National jewish Medical and Research Center, Denver, CO (United States)]|[Univ. of Colorado School of Medicine, Denver, CO (United States)

1999-04-01

302

Molten salt lithium cells  

DOEpatents

Lithium-based cells are promising for applications such as electric vehicles and load-leveling for power plants since lithium is very electropositive and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and is operated in the temperature range of about 400.degree.-500.degree. C. Such high temperature operation accelerates corrosion problems and a substantial amount of energy is lost through heat transfer. The present invention provides an electrochemical cell (10) which may be operated at temperatures between about 100.degree.-170.degree. C. Cell (10) comprises an electrolyte (16), which preferably includes lithium nitrate, and a lithium or lithium alloy electrode (12).

Raistrick, Ian D. (Menlo Park, CA); Poris, Jaime (Portola Valley, CA); Huggins, Robert A. (Stanford, CA)

1983-01-01

303

Molten salt lithium cells  

DOEpatents

Lithium-based cells are promising for applications such as electric vehicles and load-leveling for power plants since lithium is very electropositive and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and is operated in the temperature range of about 400.degree.-500.degree. C. Such high temperature operation accelerates corrosion problems and a substantial amount of energy is lost through heat transfer. The present invention provides an electrochemical cell (10) which may be operated at temperatures between about 100.degree.-170.degree. C. Cell (10) comprises an electrolyte (16), which preferably includes lithium nitrate, and a lithium or lithium alloy electrode (12).

Raistrick, Ian D. (Menlo Park, CA); Poris, Jaime (Portola Valley, CA); Huggins, Robert A. (Stanford, CA)

1982-02-09

304

Lithium power sources  

NASA Astrophysics Data System (ADS)

The theoretical and applied aspects of the development of lithium power sources are examined. The characteristics of lithium power sources with liquid and solid cathode materials are analyzed, and their performance is evaluated as a function of the discharge regime and temperature. The discussion also covers the electrochemical kinetics of the lithium electrode, inorganic and organic electrolytes, primary and secondary lithium power sources, and medium-temperature storage batteries of the system lithium/iron sulfides. Particular attention is given to the existing and prospective applications of lithium power sources of various kinds.

Kedrinskii, Il'ia A.; Dmitrenko, Vasilii E.; Grudianov, Igor'i.

305

40 CFR 421.150 - Applicability: Description of the primary beryllium subcategory.  

Code of Federal Regulations, 2012 CFR

...Applicability: Description of the primary beryllium subcategory. 421.150 Section...MANUFACTURING POINT SOURCE CATEGORY Primary Beryllium Subcategory § 421.150 Applicability: Description of the primary beryllium subcategory. The...

2012-07-01

306

40 CFR 63.11166 - What General Provisions apply to primary beryllium production facilities?  

Code of Federal Regulations, 2012 CFR

...false What General Provisions apply to primary beryllium production facilities? 63.11166 Section...Nonferrous Metals Area Sources-Zinc, Cadmium, and Beryllium Primary Beryllium Production Facilities § 63.11166 What...

2012-07-01

307

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2013 CFR

...false General license: Plutonium-beryllium special form material. 71.23 Section...23 General license: Plutonium-beryllium special form material. (a) A...fissile material in the form of plutonium-beryllium (Pu-Be) special form...

2013-01-01

308

Direct current sputtering of boron from boron/coron mixtures  

DOEpatents

A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached; and, coating the substrate material with boron by sputtering from the boron-containing rod.

Timberlake, John R. (Allentown, NJ); Manos, Dennis (Williamsburg, VA); Nartowitz, Ed (Edison, NJ)

1994-01-01

309

Direct current sputtering of boron from boron/carbon mixtures  

DOEpatents

A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached and coating the substrate material with boron by sputtering from the boron-containing rod.

Timberlake, J.R.; Manos, D.; Nartowitz, E.

1993-12-31

310

Lithium Resources for the 21st Century  

NASA Astrophysics Data System (ADS)

Lithium is an important industrial compound and the principal component of high energy-density batteries. Because it is the lightest solid element, these batteries are widely used in consumer electronics and are expected to be the basis for battery electric vehicles (BEVs), hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) for the 21st century. In view of the large incremental demand for lithium that will result from expanded use of various types of EVs, long-term estimates of lithium demand and supply are advisable. For GDP growth rates of 2 to 3% and battery recycling rates of 90 to 100%, total demand for lithium for all markets is expected to be a maximum of 19.6 million tonnes through 2100. This includes 3.2 million tonnes for industrial compounds, 3.6 million tonnes for consumer electronics, and 12.8 million tonnes for EVs. Lithium-bearing mineral deposits that might supply this demand contain an estimated resource of approximately 39 million tonnes, although many of these deposits have not been adequately evaluated. These lithium-bearing mineral deposits are of two main types, non-marine playa-brine deposits and igneous deposits. Playa-brine deposits have the greatest immediate resource potential (estimated at 66% of global resources) and include the Salar de Atacama (Chile), the source of almost half of current world lithium production, as well as Zabuye (China/Tibet) and Hombre Muerto (Argentina). Additional important playa-brine lithium resources include Rincon (Argentina), Qaidam (China), Silver Peak (USA) and Uyuni (Bolivia), which together account for about 35% of the estimated global lithium resource. Information on the size and continuity of brine-bearing aquifers in many of these deposits is limited, and differences in chemical composition of brines from deposit to deposit require different extraction processes and yield different product mixes of lithium, boron, potassium and other elements. Numerous other brines in playas (Great Salt Lake, Searles Lake), geothermal systems (Salton Sea) and oil fields contain lithium, but in low concentrations that add relatively little to estimated global resources. Igneous deposits, which constitute 26% of estimated global resources, consist largely of pegmatites, including past and present producers at Kings Mountain-Bessemer City (USA), Greenbushes (Australia) and Bikita (Zimbabwe), as well as numerous active prospects, especially in Canada and China. Amenability of these deposits to economic extraction is controlled by mineralogy and zoning of lithium, which vary considerably from deposit to deposit. An additional 8% of global lithium resources is estimated to be present in unusual deposits including largely hectorite clays in volcaniclastic rocks at Kings Valley (USA) and jadarite in lacustrine evaporite deposits (Serbia), which present new challenges to both mining and processing. If this highly varied population of deposits can be converted to reserves, lithium supplies for the 21st century EV market are relatively secure.

Kesler, S.; Gruber, P.; Medina, P.; Keolian, G.; Everson, M. P.; Wallington, T.

2011-12-01

311

Minerals Yearbook 1989: Boron.  

National Technical Information Service (NTIS)

U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California ...

P. A. Lyday

1990-01-01

312

Minerals Yearbook 1990: Boron.  

National Technical Information Service (NTIS)

U.S. production and sales of boron minerals and chemicals increased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California ...

P. A. Lyday

1991-01-01

313

Minerals Yearbook, 1993: Boron.  

National Technical Information Service (NTIS)

U.S. production and sales of boron minerals and chemicals increased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to borosilicate glass, textile-grade glass fibers, and agriculture. California was...

P. A. Lyday

1994-01-01

314

Characterization of Plasma Sprayed Beryllium ITER First Wall Mockups  

SciTech Connect

ITER first wall beryllium mockups, which were fabricated by vacuum plasma spraying the beryllium armor, have survived 3000 thermal fatigue cycles at 1 MW/sq m without damage during high heat flux testing at the Plasma Materials Test Facility at Sandia National Laboratory in New Mexico. The thermal and mechanical properties of the plasma sprayed beryllium armor have been characterized. Results are reported on the chemical composition of the beryllium armor in the as-deposited condition, the through thickness and normal to the through thickness thermal conductivity and thermal expansion, the four-point bend flexure strength and edge-notch fracture toughness of the beryllium armor, the bond strength between the beryllium armor and the underlying heat sink material, and ultrasonic C-scans of the Be/heat sink interface.

Castro, Richard G.; Vaidya, Rajendra U.; Hollis, Kendall J.

1997-12-31

315

Quantitative method of determining beryllium or a compound thereof in a sample  

SciTech Connect

A method of determining beryllium or a beryllium compound thereof in a sample, includes providing a sample suspected of comprising beryllium or a compound thereof, extracting beryllium or a compound thereof from the sample by dissolving in a solution, adding a fluorescent indicator to the solution to thereby bind any beryllium or a compound thereof to the fluorescent indicator, and determining the presence or amount of any beryllium or a compound thereof in the sample by measuring fluorescence.

McCleskey, T. Mark (Los Alamos, NM); Ehler, Deborah S. (Los Alamos, NM); John, Kevin D. (Santa Fe, NM); Burrell, Anthony K. (Los Alamos, NM); Collis, Gavin E. (Los Alamos, NM); Minogue, Edel M. (Los Alamos, NM); Warner, Benjamin P. (Los Alamos, NM)

2010-08-24

316

Physicochemical Characteristics of Aerosol Particles Generated During the Milling of Beryllium Silicate Ores: Implications for Risk Assessment  

Microsoft Academic Search

Inhalation of beryllium dusts generated during milling of ores and cutting of beryl-containing gemstones is associated with development of beryllium sensitization and low prevalence of chronic beryllium disease (CBD). Inhalation of beryllium aerosols generated during primary beryllium production and machining of the metal, alloys, and ceramics are associated with sensitization and high rates of CBD, despite similar airborne beryllium mass

Aleksandr B. Stefaniak; Steve J. Chipera; Gregory A. Day; Phil Sabey; Robert M. Dickerson; Deborah C. Sbarra; Mathew G. Duling; Robert B. Lawrence; Marcia L. Stanton; Ronald C. Scripsick

2008-01-01

317

Characterization Lithium Mineralized Pegmatite.  

National Technical Information Service (NTIS)

Lithium economic importance has increased in the last years. In Brazil its reserves, generally pegmatites bodies, are found in Itinga-Aracuai-MG. This study of characterization belongs to a global plan of lithium mineralized bodies research of 'Arqueana d...

E. F. S. Pereira O. Luz Ferreira R. Z. L. Cancado J. Mauricio Neto

1986-01-01

318

Molecular Structure of boron  

NSDL National Science Digital Library

Boron was founded in 1808 by Sir Humphry Davy and Gay-Lussac and Thenard. It occurs as orthoboric acid in volcanic spring waters and as borates in Boron and colematic. Some sources can also be found in the Mohave Desert. It is used when making glass to keep the glass from breaking under temperature stress. Also if combined with sodium hydroxide and hydrogen peroxide it makes bleach.

2002-08-26

319

Boron and Plants  

Microsoft Academic Search

\\u000a Boron is found naturally in the earths crust in the oxidized form as borax and colemanite, particularly in the oceans, sedimentary\\u000a rocks, coal, shale, and some soils. It is never found in the elemental form in nature possessing a complex chemistry similar\\u000a to that of silicon, with properties switching between metals and non-metals. Boron has become an important and strategic

Munir Ozturk; Serdal Sakcali; Salih Gucel; Huseyin Tombuloglu

320

Minerals Yearbook, 1988. Boron  

SciTech Connect

U.S. production and sales of boron minerals and chemicals decreased during the year. Glass-fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California was the only domestic source of boron minerals. The report discusses the following: domestic data coverage; legislation and government programs; domestic production; comsumption and uses; prices; foreign trade; world capacity; world review--Argentina, Chile, France, Italy, Turkey, United Kingdom; Technology.

Lyday, P.A.

1988-01-01

321

Dynamic Behavior of Beryllium as a Function of Texture  

SciTech Connect

The high-strain-rate stress-strain responses of commercial hot-pressed beryllium and rolled-sheet beryllium were studied as a function of orientation in compression and room temperature. Hot-pressed beryllium exhibits isotropic mechanical properties; whereas 16:1 rolled sheet was highly anisotropic. Rolled sheet displayed a factor of two difference in strength between the thickness and in-plane (lowest) directions. Twinning is a key deformation mechanism at high rates.

Blumenthal, W.R.; Abeln, S.P.; Mataya, M.C.; Gray, G.T. III; Cannon, D.D.

1999-01-05

322

IN VITRO STUDIES OF GRANULOMATOUS HYPERSENSITIVITY TO BERYLLIUM  

Microsoft Academic Search

Lymphocytes were obtained from normal subjects and subjects with granulomatous hypersensitivity to beryllium. Lymphocytes from sensitive persons underwent typical blastogenic transformation when exposed to BeO or BeSO4in vitro. Transformation was maximal between the fifth and sixth days of exposure and was dependent upon the concentration of beryllium.Monocytes from beryllium sensitive subjects matured into macrophages in vitro more rapidly than cells

Jon M. Hanifin; William L. Epstein; Martin J. Cline

1970-01-01

323

Density functional study of hydrogen adsorption on beryllium (0001)  

SciTech Connect

Beryllium, tungsten, and carbon are planned as wall materials for the future international tokamak. Although beryllium is not situated in a region submitted to the most dramatic plasma-wall interaction, its reactivity toward hydrogen atom impinging is of fundamental importance. This paper is devoted to theoretical study of hydrogen adsorption on the beryllium (0001) surface based on the first-principles discrete Fourier transform method. Comparison is proposed to former theoretical works and to thermal-desorption spectroscopy.

Allouche, A. [Physique des Interactions Ioniques et Moleculaires, CNRS and Universite de Provence, Campus Scientifique de Saint Jerome, service 242, 13397 Marseille Cedex 20 (France)

2008-08-15

324

Prevalence of beryllium sensitization among aluminium smelter workers  

PubMed Central

Background Beryllium exposure occurs in aluminium smelters from natural contamination of bauxite, the principal source of aluminium. Aims To characterize beryllium exposure in aluminium smelters and determine the prevalence rate of beryllium sensitization (BeS) among aluminium smelter workers. Methods A population of 3185 workers from nine aluminium smelters owned by four different aluminium-producing companies were determined to have significant beryllium exposure. Of these, 1932 workers participated in medical surveillance programmes that included the serum beryllium lymphocyte proliferation test (BeLPT), confirmation of sensitization by at least two abnormal BeLPT test results and further evaluation for chronic beryllium disease in workers with BeS. Results Personal beryllium samples obtained from the nine aluminium smelters showed a range of <0.0113.00 ?g/m3 time-weighted average with an arithmetic mean of 0.25 ?g/m3 and geometric mean of 0.06 ?g/m3. Nine workers were diagnosed with BeS (prevalence rate of 0.47%, 95% confidence interval = 0.210.88%). Conclusions BeS can occur in aluminium smelter workers through natural beryllium contamination of the bauxite and further concentration during the refining and smelting processes. Exposure levels to beryllium observed in aluminium smelters are similar to those seen in other industries that utilize beryllium. However, compared with beryllium-exposed workers in other industries, the rate of BeS among aluminium smelter workers appears lower. This lower observed rate may be related to a more soluble form of beryllium found in the aluminium smelting work environment as well as the consistent use of respiratory protection.

Slade, M. D.; Cantley, L. F.; Kirsche, S. R.; Wesdock, J. C.; Cullen, M. R.

2010-01-01

325

Beryllium pressure vessels for creep tests in magnetic fusion energy  

Microsoft Academic Search

Beryllium has interesting applications in magnetic fusion experimental machines and future power-producing fusion reactors. Chief among the properties of beryllium that make these applications possible is its ability to act as a neutron multiplier, thereby increasing the tritium breeding ability of energy conversion blankets. Another property, the behavior of beryllium in a 14-MeV neutron environment, has not been fully investigated,

Neef

1990-01-01

326

Two and Three Neutron Halos in Helium and Lithium Isotopes  

NASA Astrophysics Data System (ADS)

The far reaching shape of the matter distributions (halo) of exotic nuclei with high isospin components is calculated in the Dynamic-Correlation Model (DCM) which is based on the interaction of valence- and core-particles. In this model, one, two, or more valence particles and intrinsic vacuum-clusters (collective-excitations of reference vacuum) are treated within the same formalism. Matter and charge distributions of lithium and beryllium isotopes are strongly modulated by the coupling of the valence particles with the core, and the matter radii extracted from the theoretical distributions are in good agreement with experimental results. Within the model the core-protons are contributing de facto to the halo formation. The effect of the core excitation mechanism on the calculated cross sections for proton scattering on helium and lithium isotopes is analyzed. For the charge radii new experiments based on the determination of the volume-shift are discussed.

Tomaselli, M.; Khl, T.; Egelhof, P.; Nrtershuser, W.; Dax, A.; Wang, H.; Marx, D.; Neumaier, S. R.; Kluge, H.-J.; Tanihata, I.; Fritzsche, S.; Mutterer, M.

2002-12-01

327

Boron as an Alternate Engine Fuel  

Microsoft Academic Search

Boron fuel is made up of the element boron. Boron as a chemical fuel will be a promising engine fuel in the future. Cars in which boron fuel simply burns will be true zero emission vehicles. Total world production of boron minerals was approximately 4,270,000 tons in 2000. Turkey has the largest boron sources in the world. It is estimated

M. Balat

2007-01-01

328

Testing of Liquid Lithium Limiters in CDX-U  

SciTech Connect

Part of the development of liquid metals as a first wall or divertor for reactor applications must involve the investigation of plasma-liquid metal interactions in a functioning tokamak. Most of the interest in liquid-metal walls has focused on lithium. Experiments with lithium limiters have now been conducted in the Current Drive Experiment-Upgrade (CDX-U) device at the Princeton Plasma Physics Laboratory. Initial experiments used a liquid-lithium rail limiter (L3) built by the University of California at San Diego. Spectroscopic measurements showed some reduction of impurities in CDX-U plasmas with the L3, compared to discharges with a boron carbide limiter. While no reduction in recycling was observed with the L3, which had a plasma-wet area of approximately 40 cm2, subsequent experiments with a larger area fully toroidal lithium limiter demonstrated significant reductions in both recycling and in impurity levels. Two series of experiments with the toroidal limiter have now be en performed. In each series, the area of exposed, clean lithium was increased, until in the latest experiments the liquid-lithium plasma-facing area was increased to 2000 cm2. Under these conditions, the reduction in recycling required a factor of eight increase in gas fueling in order to maintain the plasma density. The loop voltage required to sustain the plasma current was reduced from 2 V to 0.5 V. This paper summarizes the technical preparations for lithium experiments and the conditioning required to prepare the lithium surface for plasma operations. The mechanical response of the liquid metal to induced currents, especially through contact with the plasma, is discussed. The effect of the lithium-filled toroidal limiter on plasma performance is also briefly described.

R. Majeski; R. Kaita; M. Boaz; P. Efthimion; T. Gray; B. Jones; D. Hoffman; H. Kugel; J. Menard; T. Munsat; A. Post-Zwicker; V. Soukhanovskii; J. Spaleta; G. Taylor; J. Timberlake; R. Woolley; L. Zakharov; M. Finkenthal; D. Stutman; G. Antar; R. Doerner; S. Luckhardt; R. Seraydarian; R. Maingi; M. Maiorano; S. Smith; D. Rodgers

2004-07-30

329

Epidemiology of beryllium sensitization and disease in nuclear workers  

SciTech Connect

We examined the epidemiology of chronic beryllium disease among a stratified, random sample (n = 895) of nuclear weapons workers using the blood beryllium lymphocyte transformation (BeLT) test and chest radiograph for case identification. Of 18 new cases of beryllium sensitization, 12 had beryllium disease, and three more developed pulmonary granulomas on lung biopsy over the succeeding 2 yr. Beryllium-sensitized cases did not differ from noncases in age, gender, race, ethnicity, smoking, most respiratory symptoms, spirometric or radiographic abnormalities, or job tenure. The six sensitized cases without initial disease differed from beryllium disease cases in having greater pack-years of smoking. Sensitization occurred among workers with inadvertent or bystander exposure, such as a secretary and security guard. However, beryllium sensitization risk was higher for machinists (4.7%) and for persons reporting measured overexposure (7.4%, odds ratio 5.1); exposure beginning before 1970 (3.6%, odds ratio 2.7); consistent beryllium exposure (3.4%); and sawing (4.7%) or band sawing (6.0%) of beryllium metal. We conclude that both individual susceptibility to sensitization and exposure circumstances are important in developing disease.

Kreiss, K.; Mroz, M.M.; Zhen, B.; Martyny, J.W.; Newman, L.S. (National Jewish Center for Immunology and Respiratory Medicine, Denver, CO (United States))

1993-10-01

330

Lithium batteries: Future batteries  

Microsoft Academic Search

The main characteristics and applications of lithium batteries are reviewed. Miniature batteries for quartz crystal watches have been developed and fabricated in Switzerland since 1970. High technology systems like lithium batteries are largely used for their low auto-discharge during storage and for their high energy density. Two kinds of lithium batteries can be distinguished concerning their place in the watch:

Harald Reiche

1991-01-01

331

Lithium nephrotoxicity revisited  

Microsoft Academic Search

Lithium is widely used to treat bipolar disorder. Nephrogenic diabetes insipidus (NDI) is the most common adverse effect of lithium and occurs in up to 40% of patients. Renal lithium toxicity is characterized by increased water and sodium diuresis, which can result in mild dehydration, hyperchloremic metabolic acidosis and renal tubular acidosis. The concentrating defect and natriuretic effect develop within

Bernard C. Rossier; Jean-Pierre Grnfeld

2009-01-01

332

Organometallic for Lithium Intercalation.  

National Technical Information Service (NTIS)

The goal of the Phase I program was to determine whether pairs of electrodes containing tetraazaannulenes (TAAs) can be used as the anode and cathode in a lithium metal-free lithium secondary cell. The extent of chemical and electrochemical lithium interc...

S. S. Yuan F. Walsh

1984-01-01

333

Lithium Polymer Electrolytes  

Microsoft Academic Search

The present development trend in lithium ion batteries is focused on the replacement of the common liquid electrolyte with a lithium ion conducting polymer electrolyte membrane to finally achieve the fabrication of batteries having a full plastic structure. Such plastic lithium ion batteries are expected to be less expensive and more easily scaled up than their liquid counterparts. In addition,

Bruno Scrosati

334

Lithium fuel cells  

Microsoft Academic Search

The main goal of our research project is to design safe, high energy and power density lithium\\/water systems. We explored the feasibility of substituting the natural bilayer (formed on the lithium surface when lithium is in contact with water), for a thin polymeric film. By substituting the natural bilayer film we hope to reduce the parasitic reactions occurring at the

Mirna Urquidi-Macdonald; Homero Castaneda; Angela M. Cannon

2002-01-01

335

An embedded atom method potential of beryllium  

NASA Astrophysics Data System (ADS)

We present an embedded atom method (EAM) potential for hexagonal beryllium, with a pair function in the form of a Morse potential and a Johnson embedding function with exponential electron density. The cohesive energy, elastic constants, lattice parameters and relaxed vacancy formation energy were used to fit the potential. The fitted-potential was validated by a comparison to first-principles and, wherever available, experimental results for the lattice energies of various crystal structures: vacancy cluster, interstitial formation and surface. Using a large cutoff distance of 5 , which includes interactions to approximately the eighth neighbor shell of beryllium, allows our potential to reproduce these quantities considerably better than previous EAM potentials. The accuracy obtained by our potential is similar to or in some cases even better than available modified EAM potentials, while being computationally less intensive.

Agrawal, Anupriya; Mishra, Rohan; Ward, Logan; Flores, Katharine M.; Windl, Wolfgang

2013-12-01

336

Aging beryllium bronze in pulsed magnetic fields  

NASA Astrophysics Data System (ADS)

Methods of microhardness and X-ray diffraction were used to study the kinetics of changes in the microstructure of the beryllium bronze alloy BrB-2 in the process of decomposition of the supersaturated solid solution in a pulsed magnetic field with a frequency from 0 to 7 Hz at an amplitude of the pulse of 318.4 kA/m, a dc component of the magnetic field equal to 238.8 kA/m, at a temperature of 350C and annealing duration of 1 h. Frequency dependences of the microhardness, lattice parameter, concentration of beryllium in the residual matrix, size of coherent domains, dislocation density, and relative microdeformations of mosaic blocks in the matrix have been measured upon aging with and without pulse magnetic field. The results of experiments show that the pulse magnetic field substantially affects the parameters of the fine structure and physicomechanical properties of the bronze.

Osinskaya, Yu. V.; Pokoev, A. V.

2008-04-01

337

Molybdenum-ruthenium/beryllium multilayer coatings  

SciTech Connect

A newly developed beryllium-based multilayer system consisting of polycrystalline Be and amorphous MoRu layers is presented. The multilayer exhibits many remarkable properties: reflectivity as high as 69.3% at a wavelength of 11.4 nm (achieved with 50 bilayers giving a bandwidth of 0.35 nm), near-zero intrinsic stress, and excellent smoothing properties. As compared with Mo/Si multilayers at 13.4 nm, the shorter wavelength of 11.4 nm is better matched to the spectral output of gas-jet laser produced plasma sources, allowing a much higher optical throughput of the extreme ultraviolet lithography (EUVL) tool. The properties of MoRu/Be are compared to other beryllium-based multilayers, which have been considered for reflective coatings for EUVL optics. (c) 2000 American Vacuum Society.

Bajt, Sasa [Information Science and Technology Program, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2000-03-01

338

Electronic bistability in linear beryllium chains.  

PubMed

A theoretical investigation on the mixed-valence behavior (bistability) of a series of cationic linear chains composed of beryllium atoms, Be(N)(+) (with N = 6,..., 12), is presented. The calculations were performed at CAS-SCF and MR-CI levels by using an ANO basis set containing 6s4p3d2f orbitals for each atom. Our results show a consistent gradual shift between different classes of mixed-valence compounds as the number of beryllium atoms increases, from class III strong coupling toward class II valence trapped. Indeed, in the largest cases (N > 10), the cationic chains were found to be closer to class I, where the coupling vanishes. The intramolecular electron transfer parameters V(ab), E(a), and E(opt) were calculated for each atomic chain. It is shown that the decrease of V(ab) with increasing N follows an exponential pattern. PMID:19334736

Helal, Wissam; Monari, Antonio; Evangelisti, Stefano; Leininger, Thierry

2009-04-30

339

Boron-Based Layered Structures for Energy Storage  

SciTech Connect

Based on Density Functional Theory simulations, we have studied the boron-based graphite-like materials, i.e., LiBC and MgB2 for energy storage. First, when half of the Li-ions in the LiBC are removed, the BC layered structure is still preserved. The Li intercalation potential (equilibrium lithium-insertion voltage of 2.3-2.4 V relative to lithium metal) is significantly higher than that in graphite, allowing Li0.5BC to function as a cathode material. The reversible electrochemical reaction, LiBC = Li0.5BC + 0.5Li, enables a specific energy density of 1088 Wh/kg and a volumetric energy density of 2463 Wh/L. Second, 75% of the Mg ions in MgB2 can be removed and reversibly inserted with the layered boron structures being preserved through an in-plane topological transformation between the hexagonal lattice domains and triangular domains. The mechanism of such a charge-driven transformation originates from the versatile valence state of boron in its planar form.

Zhao, Y.; Wei, S. H.

2012-01-01

340

Diffusion bonding of beryllium-copper alloys  

Microsoft Academic Search

A process has been developed for diffusion-bonding identical beryllium-copper alloy, 1.8 to 2.0 wt% Be, which has produced bond strengths comparable to that of the bulk. Bonding resulted from self-diffusion between two Be-Cu samples, brought into intimate contact and heated in a high vacuum. Metallurgical analyses of the diffusion bonds revealed the bond interface to be a continuous high-angle planar

D. C. Eckman; B. Z. Rosenblum; C. Q. Bowles

1992-01-01

341

Analysis of surface contaminants on beryllium windows  

SciTech Connect

It is known that various crystalline and liquid compounds form on the downstream surfaces of beryllium windows exposed to air. It is also known that the integrity of such windows may be compromised resulting in leaks through the window. The purpose of this report is to document the occurrences described as they pertain to the NSLS and to analyze, where possible, the various substances formed.

Gmur, N.F.

1986-12-01

342

Infrared spectra of organic beryllium complexes  

Microsoft Academic Search

1.The same bands are always observed in the 7001300 cm' region of the infrared spectra of coordination compounds with the same ligand but different metals, since the bands come from ligand vibrations.2.A wide and intense band at 830 cm-1 is observed in the infrared spectra of all the beryllium coordination compounds studied. This band is absent from the spectra of

V. V. Korshak; L. I. Komarova; T. A. Sidorov

1962-01-01

343

Beryllium and titanium cost-adjustment report  

Microsoft Academic Search

This report summarizes cost adjustment factors for beryllium (Be, S200) and titanium (Ti, 6Al-4V) that were derived relative to aluminum (Al, 7075-T6). Aluminum is traditionally the material upon which many of the Cost Analysis Office, Missile Division cost estimating relationships (CERs) are based. The adjustment factors address both research and development and production (Q > 100) quantities. In addition, the

John Owen; Eric Ulph

1991-01-01

344

Galactic Evolution of Beryllium and Oxygen  

Microsoft Academic Search

We discuss the early evolution of beryllium and oxygen in our Galaxy by comparing abundances of these elements for halo and disk metal-poor stars. Both, O and Be rise as we go progressively to more metal-rich stars, showing a slope 0.41 +-0.09 ([Be\\/O] vs [Fe\\/H]) for stars with [Fe\\/H] < -1. This relationship provides an observational constraint to the actually

Garik Israelian; R. J. G. Lpez; Rafael Rebolo

2000-01-01

345

Molybdenum-ruthenium\\/beryllium multilayer coatings  

Microsoft Academic Search

A newly developed beryllium-based multilayer system consisting of polycrystalline Be and amorphous MoRu layers is presented. The multilayer exhibits many remarkable properties: reflectivity as high as 69.3% at a wavelength of 11.4 nm (achieved with 50 bilayers giving a bandwidth of 0.35 nm), near-zero intrinsic stress, and excellent smoothing properties. As compared with Mo\\/Si multilayers at 13.4 nm, the shorter

Sasa. Bajt; Sasa

2000-01-01

346

Beryllium window for an APS diagnostics beamline  

SciTech Connect

A beryllium (Be) window for an Advanced Photon Source (APS) diagnostics beamline has been designed and built. The window, which has a double concave axisymmetrical profile with a thickness of 0.5 mm at the center, receives 160 W/mm{sup 2} (7 GeV/100 mA stored beam) from an undulator beam. The window design as well as thermal and thermomechanical analyses, including thermal buckling of the Be window, are presented.

Sheng, I.C.; Yang, B.X.; Sharma, Y.S.

1997-09-01

347

Electrochemical performance of low temperature fluorinated graphites used as cathode in primary lithium batteries  

Microsoft Academic Search

The present study highlights the electrochemical performance of two series of fluorinated graphites used as the cathode in primary lithium batteries. These compounds were prepared under fluorine gas at room temperature using a catalytic atmosphere made of boron or chlorine fluoride, and then thermally treated between 100 and 600C. The electrochemical properties are correlated to a complete physico-chemical characterization, already

C. Delabarre; M. Dubois; J. Giraudet; K. Gurin; A. Hamwi

2006-01-01

348

Radiation Damage and Defect Behavior in Ion-Implanted, Lithium Counterdoped Silicon Solar Cells.  

National Technical Information Service (NTIS)

Boron doped silicon n+p solar cells were counterdoped with lithium by ion implanation and the resultant n+p cells irradiated by 1 MeV electrons. The function of fluence and a Deep Level Transient Spectroscopy (DLTS) was studied to correlate defect behavio...

I. Weinberg S. Mehta C. K. Swartz

1984-01-01

349

Marked tachypnea in siblings with chronic beryllium disease due to copper-beryllium alloy.  

PubMed

Two biological sisters working at the same factory for > 9 years developed chronic beryllium disease (CBD) from a copper-beryllium alloy. Both had marked tachypnea (36 breaths/min and 45 breaths/min at rest, respectively), persisting over 8 years. Ventilation during exercise (assessed in one sibling) was grossly excessive (57 L/min, expected 23 L/min) with a respiratory rate of 64 breaths/min even with normal baseline routine pulmonary function tests. Blood beryllium lymphocyte transformation test and lung biopsies confirmed the diagnosis. No other cases of CBD have been reported from this plant among about 120 workers. These cases support the genetic basis for berylliosis and illustrate the marked tachypnea that may accompany this disease. PMID:11171753

Tarlo, S M; Rhee, K; Powell, E; Amer, E; Newman, L; Liss, G; Jones, N

2001-02-01

350

Lithium Metal Oxide Electrodes for Lithium Batteries.  

National Technical Information Service (NTIS)

An uncycled preconditioned electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula Li(sub (2+2x)/(2+x))M'(sub 2x/(2+x))M(sub (2-2x)/(2+x))O(sub 2-delta), in which 0 < or = x < 1 and delta is less than 0....

C. S. Johnson K. Amine M. M. Thackeray S. H. Kang

2006-01-01

351

Simulating the FTICR-MS signal of a decaying beryllium-7 ion plasma in a two-dimensional electrostatic PIC code  

NASA Astrophysics Data System (ADS)

Beryllium-7 (Be-7) only decays by electron capture into lithium-7 (Li-7) with a half life of 53 days. We study the effect of ionization on this decay rate. We do so by trapping a Be-7 ion plasma in a cylindrical Malmberg-Penning trap and measuring Be-7 and Li-7 concentrations as functions of time by using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). We have simulated these signals in a 2-dimensional electrostatic particle-in-cell (PIC) code. The two spectrum peaks merge at high ion densities whereas at low ion densities they can be resolved. The merged peak shifts linearly according to the relative abundances of these species. We have also simulated singly-ionized beryllium-7 hydride (BeH+) and Li-7 ion plasmas at high densities. These two separate peaks shift according to their relative abundances. We describe an analytical model that explains how these peaks shift. Keywords: beryllium-7, electron capture, lithium-7, ion plasma, Fourier transform ion cyclotron mass spectrometry, FTICR-MS, FTMS, 2D electrostatic particle-in-cell, PIC, simulation

Nakata, Michael Takeshi

352

Determination of Natural Beryllium (Be) in Soil and Swipe Samples Utilizing Yttrium/Beryllium Ratio  

SciTech Connect

1. Objective: A method to determine whether beryllium (Be) components in surface swipe samples are from a natural source is needed. 2. Methods: Soil samples and surface swipes from area facilities were analyzed for marker elements to identify source pathways for beryllium (Be). To be useful, the natural marker element must be present at reasonably consistent levels across the site, must correlate with the Be concentration, and not have the potential to be present from non-natural sources. 3. Results: The research on marker elements used to identify source pathways for beryllium (Be) concentrations demonstrates a clear correlation between Be and yttrium (Y) in natural soils on the Nevada National Security Site. The Y/Be ratio is proposed as a method to characterize the source of Be in soil and surface swipe samples and to aid in recommendations for follow up actions. Swipe samples are analyzed using an ICP/MS method and compared with results from soil samples. Natural soil constituent levels and the Y/Be Ratio range is determined for the occupied and historical facilities and surrounding areas. Y/Be ratios within the statistical range established indicate the Be is from a natural source. Y/Be ratios lower than this range indicate the presence of another Be source, and may then be correlated to alloy, ceramic, or other operational sources by the ratios of copper, nickel, cobalt, uranium, and/or niobium. Example case studies of evaluations of buildings with historical operational beryllium usage, current ongoing technical processes, and heavy equipment used in large building demolitions are included demonstrating the value of the ratio approach. 4. Conclusions: This differentiation is valuable as there is no known correlation between natural beryllium in soil and beryllium disease.

None

2010-09-30

353

Lithium use in batteries  

USGS Publications Warehouse

Lithium has a number of uses but one of the most valuable is as a component of high energy-density rechargeable lithium-ion batteries. Because of concerns over carbon dioxide footprint and increasing hydrocarbon fuel cost (reduced supply), lithium may become even more important in large batteries for powering all-electric and hybrid vehicles. It would take 1.4 to 3.0 kilograms of lithium equivalent (7.5 to 16.0 kilograms of lithium carbonate) to support a 40-mile trip in an electric vehicle before requiring recharge. This could create a large demand for lithium. Estimates of future lithium demand vary, based on numerous variables. Some of those variables include the potential for recycling, widespread public acceptance of electric vehicles, or the possibility of incentives for converting to lithium-ion-powered engines. Increased electric usage could cause electricity prices to increase. Because of reduced demand, hydrocarbon fuel prices would likely decrease, making hydrocarbon fuel more desirable. In 2009, 13 percent of worldwide lithium reserves, expressed in terms of contained lithium, were reported to be within hard rock mineral deposits, and 87 percent, within brine deposits. Most of the lithium recovered from brine came from Chile, with smaller amounts from China, Argentina, and the United States. Chile also has lithium mineral reserves, as does Australia. Another source of lithium is from recycled batteries. When lithium-ion batteries begin to power vehicles, it is expected that battery recycling rates will increase because vehicle battery recycling systems can be used to produce new lithium-ion batteries.

Goonan, Thomas G.

2012-01-01

354

Process for making boron nitride using sodium cyanide and boron  

DOEpatents

This a very simple process for making boron nitride by mixing sodium cyanide and boron phosphate and heating the mixture in an inert atmosphere until a reaction takes place. The product is a white powder of boron nitride that can be used in applications that require compounds that are stable at high temperatures and that exhibit high electrical resistance.

Bamberger, Carlos E. (Oak Ridge, TN)

1990-01-01

355

Method for separating boron isotopes  

DOEpatents

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

Rockwood, Stephen D. (Los Alamos, NM)

1978-01-01

356

Boron Hydride Polymer Coated Substrates.  

National Technical Information Service (NTIS)

A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced i...

R. K. Pearson R. I. Bystroff D. E. Miller

1986-01-01

357

A Pentafluorophenylboron Oxalate Additive in Non-aqueous Electrolytes 3 for Lithium Batteries  

SciTech Connect

A novel compound named pentafluorophenylboron oxalate (PFPBO) has been synthesized. PFPBO has a unique molecular structure containing a boron atom center with electron deficiency and an oxalate group. It is found that when PFPBO is used as additive, the solubility of lithium fluoride (LiF) or lithium oxide (Li{sub 2}O, Li{sub 2}O{sub 2}) in propylene carbonate (PC) and dimethyl carbonate (DMC) solvents can be increased dramatically. The new electrolytes show high ionic conductivity, high lithium ion transference number and good compatibility with LiMn{sub 2}O{sub 4} cathode and MCMB anode. PFPBO was synthesized with the designed structure to act as a bi-functional additive: boron-based anion receptor (BBAR) additive and stable solid electrolyte interphase (SEI) formation additive in PC-based electrolytes. The results show it does possess these two desired functionalities.

Yang, X.Q.; Li, L.F.; Lee, H.S.; Li, H.; Huang, X.J.

2009-12-01

358

Dissolution of beryllium in artificial lung alveolar macrophage phagolysosomal fluid.  

PubMed

Dissolution of a lung burden of poorly soluble beryllium particles is hypothesized to be necessary for development of chronic beryllium lung disease (CBD) in humans. As such, particle dissolution rate must be sufficient to activate the lung immune response and dissolution lifetime sufficient to maintain chronic inflammation for months to years to support development of disease. The purpose of this research was to investigate the hypothesis that poorly soluble beryllium compounds release ions via dissolution in lung fluid. Dissolution kinetics of 17 poorly soluble particulate beryllium materials that span extraction through ceramics machining (ores, hydroxide, metal, copper-beryllium [CuBe] fume, oxides) and three CuBe alloy reference materials (chips, solid block) were measured over 31 d using artificial lung alveolar macrophage phagolysosomal fluid (pH 4.5). Differences in beryllium-containing particle physicochemical properties translated into differences in dissolution rates and lifetimes in artificial phagolysosomal fluid. Among all materials, dissolution rate constant values ranged from 10(-5) to 10(-10)gcm(-2)d(-1) and half-times ranged from tens to thousands of days. The presence of magnesium trisilicate in some beryllium oxide materials may have slowed dissolution rates. Materials associated with elevated prevalence of CBD had faster beryllium dissolution rates [10(-7)-10(-8)gcm(-2)d(-1)] than materials not associated with elevated prevalence (p<0.05). PMID:21251696

Stefaniak, Aleksandr B; Virji, M Abbas; Day, Gregory A

2011-01-19

359

Performance of a beryllium copper nonmagnetic drill collar alloy  

Microsoft Academic Search

Laboratory characterization and field testing show the advantages of beryllium copper Alloy 25 for use in non-magnetic drill collars, stabilizers, and subs. Beryllium copper is resistant to stress corrosion cracking failures at elevated temperature and pressure in the presence of hydrogen sulfide and dissolved chloride solutions. The alloy is more resistant than stainless steel to galling failure in threaded joints.

Dunlevey

1984-01-01

360

Friction behaviour evaluation in berylliumcopper threaded connections  

Microsoft Academic Search

Berylliumcopper alloys present a combination of high tensile and compressive strength, high hardness, good thermal conductivity and high resistance to seizing and galling (conditions where metals begin to cold weld or bond under the joint influence of compressive stress and relative motion at temperatures far below the melting temperature). These properties make berylliumcopper an excellent choice for bearing and bushing

S. Baragetti; A. Terranova; M. Vimercati

2009-01-01

361

Design Alternatives for Cryogenic Beryllium Windows in an ICF Cryostat.  

National Technical Information Service (NTIS)

We propose three backup design options for the cryogenic beryllium windows in a cryostat. The first, a beryllium flange option, reduces peak tensile stresses to 1/3 of that in the original design. The second, a fiberglass flange option, reduces peak tensi...

J. H. Pitts P. R. Landon M. A. Gerhard

1984-01-01

362

Design alternatives for cryogenic beryllium windows in an ICF cryostat  

Microsoft Academic Search

We propose three backup design options for the cryogenic beryllium windows in a cryostat. The first, a beryllium flange option, reduces peak tensile stresses to 1\\/3 of that in the original design. The second, a fiberglass flange option, reduces peak tensile stresses to 1\\/2 of that in the original design and is also low cost. A third option, replacing the

J. H. Pitts; P. R. Landon; M. A. Gerhard

1984-01-01

363

Simulating beryllium electrorefining with AspenPlus{copyright}  

SciTech Connect

Beryllium is a lightweight, high strength metal with excellent thermal properties. It is a high cost material that has applications in electronics, the space program, and the defense industry. Beryllium is irreplaceable in several defense applications and therefore the US government maintains a reserve supply of several grades of the metal. However, the current defense industry (the largest metallic beryllium user) use has dwindled to the point that the only metallic beryllium producer in the US, Brush Wellman Inc., continually evaluates the profitability of continued production. The production dilemma has been compounded by health concerns associated with the generation of beryllium fines during production. An electrorefining method, previously developed, shows promise for recycling low purity beryllium scraps and produces a high grade material. Recycling and purification can reduce costs and waste disposal problems and increase the beryllium reserves in the event that Brush Wellman discontinues production. In this paper, the authors demonstrate how to use a commercially available process simulator for improving a process to electrorefine both scrap and low purity beryllium into a high purity product.

Polston, C.E.; Parkinson, W.J.; Abeln, S.P.; Wantuck, P.J.; Corle, R.R.

1998-12-01

364

HEALTH ASSESSMENT DOCUMENT FOR BERYLLIUM (1998 FINAL REPORT)  

EPA Science Inventory

EPA is announcing the release of the final report, Toxicological Review of Beryllium and Compounds: in support of the Integrated Risk Information System (IRIS) . The updated Summary for Beryllium and Compounds and accompanying Quickview have also been added to the IRIS Data...

365

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR BERYLLIUM AND COMPOUNDS  

EPA Science Inventory

EPA's assessment of the noncancer health effects and carcinogenic potential of Beryllium was added to the IRIS database in 1998. The IRIS program is updating the IRIS assessment for Beryllium. This update will incorporate health effects information published since the last assess...

366

Beryllium sensitivity is linked to HLA-DP genotype  

Microsoft Academic Search

Chronic beryllium disease (CBD) appears to arise from a combination of both exposure and genetic risk factors. A distinguishing feature of CBD is beryllium hypersensitivity, which can be measured in vitro by a lymphocyte proliferation test. The objective of this study was to determine whether certain allelic variations of the HLA-DPB1 gene, which had been observed previously in CBD, could

Zaolin Wang; Georgia M Farris; Lee S Newman; Yulin Shou; Lisa A Maier; Hugh N Smith; Babetta L Marrone

2001-01-01

367

A mortality study of workers at seven beryllium processing plants  

Microsoft Academic Search

The International Agency for Research on Cancer (IARC) has found that the evidence for the carcinogenicity of beryllium is sufficient based on animal data but limited based on human data. This analysis reports on a retrospective cohort mortality study among 9,225 male workers employed at seven beryllium processing facilities for at least 2 days between January 1, 1940, and December

Elizabeth Ward; Andrea Okun; Avima Ruder; Marilyn Fingerhut; Kyle Steenland

1992-01-01

368

X-ray focusing with compound lenses made from beryllium  

Microsoft Academic Search

We have measured the intensity profile and transmission of x rays focused by a series of biconcave spherical unit lenses fabricated from beryllium. The use of beryllium extends the range of operation of compound refractive lenses, improving transmission, aperture size, and gain. The compound refractive lens was composed of 160 biconcave unit lenses, each with a radius of curvature of

H. R. Beguiristain; J. T. Cremer; M. A. Piestrup; C. K. Gary; R. H. Pantell

2002-01-01

369

Trace-elements systematics of beryllium in terrestrial materials  

Microsoft Academic Search

Although often studied as key constituent in minerals, the low mass element (Z = 4; M = 9.0012182 amu) beryllium is most commonly encountered as a very low abundance trace metal in rocks and fluids. In terms of atomic structure and valence state, Be is affiliated with alkaline earth elements; but geologically and chemically beryllium shows greater affinities to the

Jeffrey G Ryan

2002-01-01

370

BERYLLIUM AS A MODERATOR AND REFLECTOR FOR NUCLEAR REACTORS  

Microsoft Academic Search

Beryllium is considered to be basically an excellent material for ; moderators and reflectors in nuclear reactors, because of its nuclear properties ; and many of its other physical and mechanical properties. Although known for a ; long time, beryllium has been developed into an engineering material only during ; the last few years. This review covers the latest international

Hausner

1963-01-01

371

In Vivo Boron Uptake Determination for Boron Neutron Capture Synovectomy  

SciTech Connect

Boron neutron capture synovectomy (BNCS) has been proposed as a new application of the boron neutron capture reaction for the treatment of rheumatoid arthritis. In BNCS, a boron compound is injected into the joint space, where it is taken up by the synovium. The joint is then irradiated with neutrons of a desired energy range, inducing the boron neutron capture reaction in boron-loaded cells. Boron uptake by the synovium is an important parameter in the assessment of the potential of BNCS and in the determination of whether to proceed to animal irradiations for the testing of therapeutic efficacy. We present results from an investigation of boron uptake in vivo by the synovium.

Binello, Emanuela; Shortkroff, Sonya; Yanch, Jacquelyn C.

1999-06-06

372

Boron Addition to Model Austenitic Steels and void Nucleation  

SciTech Connect

Fe-15Cr-16Ni, -0.25Ti, -500appmB, and -0.25Ti-500appmB have been irradiated in FFTF/MOTA over a wide range of dose rate which covers more than two orders difference in magnitude, within the very limited temperature range of 387-444 C. The effects of dose rate and boron addition on swelling are examined. Lower dose rates increase the swelling by shortening the incubation dose for swelling. Addition of boron does not significantly change the swelling nor the dose rate dependence of swelling for both the ternary and Ti-modified alloy. The helium pressure of cavities is found to be much smaller than the surface tension at every irradiation condition including the lowest dose and dose rate, helium generated by boron transmutant does not play any role in cavity formation in this experiment. Cavities form without helium. The difference in cavity morphology by boron addition is most likely caused by formation of borides and by lithium.

Okita, T; Wolfer, W G; Garner, F A; Sekimura, N

2003-10-30

373

Method for fabricating beryllium-based multilayer structures  

DOEpatents

Beryllium-based multilayer structures and a process for fabricating beryllium-based multilayer mirrors, useful in the wavelength region greater than the beryllium K-edge (111 .ANG. or 11.1 nm). The process includes alternating sputter deposition of beryllium and a metal, typically from the fifth row of the periodic table, such as niobium (Nb), molybdenum (Mo), ruthenium (Ru), and rhodium (Rh). The process includes not only the method of sputtering the materials, but the industrial hygiene controls for safe handling of beryllium. The mirrors made in accordance with the process may be utilized in soft x-ray and extreme-ultraviolet projection lithography, which requires mirrors of high reflectivity (>60%) for x-rays in the range of 60-140 .ANG. (60-14.0 nm).

Skulina, Kenneth M. (Livermore, CA); Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Alford, Craig S. (Tracy, CA)

2003-02-18

374

Release of beryllium into artificial airway epithelial lining fluid.  

PubMed

Inhaled beryllium particles that deposit in the lung airway lining fluid may dissolve and interact with immune-competent cells resulting in sensitization. As such, solubilization of 17 beryllium-containing materials (ore, hydroxide, metal, oxide, alloys, and process intermediates) was investigated using artificial human airway epithelial lining fluid. The maximum beryllium release in 7 days was 11.78% (from a beryl ore melter dust), although release from most materials was < 1%. Calculated dissolution half-times ranged from 30 days (reduction furnace material) to 74,000 days (hydroxide). Despite rapid mechanical clearance, billions of beryllium ions may be released in the respiratory tract via dissolution in airway lining fluid. Beryllium-containing particles that deposit in the respiratory tract dissolve in artificial lung epithelial lining fluid, thereby providing ions for absorption in the lung and interaction with immune-competent cells in the respiratory tract. PMID:23074979

Stefaniak, Aleksandr B; Virji, M Abbas; Day, Gregory A

2012-01-01

375

Method of recycling lithium borate to lithium borohydride through diborane  

DOEpatents

This invention provides a method for the recycling of lithium borate to lithium borohydride which can be reacted with water to generate hydrogen for utilization as a fuel. The lithium borate by-product of the hydrogen generation reaction is reacted with hydrogen chloride and water to produce boric acid and lithium chloride. The boric acid and lithium chloride are converted to lithium borohydride through a diborane intermediate to complete the recycle scheme.

Filby, Evan E. (Rigby, ID)

1976-01-01

376

Minerals Yearbook 1989: Boron  

SciTech Connect

U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to distributors, textile-grade glass fibers, and borosilicate glasses. California was the only domestic source of boron minerals. The United States continued to provide essentially all of its own supply while maintaining a strong position as a source of sodium borate products and boric acid exported to foreign markets. Supplementary U.S. imports of Turkish calcium borate and calcium-sodium borate ores, borax, and boric acid, primarily for various glass uses, continued.

Lyday, P.A.

1990-08-01

377

Boron Requirement in Cyanobacteria 1  

PubMed Central

The effect of boron on heterocystous and nonheterocystous dinitrogen fixing Cyanobacteria was examined. The absence of boron in culture media inhibited growth and nitrogenase activity in Nodularia sp., Chlorogloeopsis sp., and Nostoc sp. cultures. Examinations of boron-deficient cultures showed changes in heterocyst morphology. However, cultures of nonheterocystous Cyanobacteria, Gloeothece sp. and Plectonema sp., grown in the absence of boron did not show any alteration in growth or nitrogenase activity. These results suggest a requirement of boron only by heterocystous Cyanobacteria. A possible role for this element in the early evolution of photosynthetic organisms is proposed. Images Figure 4 Figure 5 Figure 6

Bonilla, Ildefonso; Garcia-Gonzalez, Mercedes; Mateo, Pilar

1990-01-01

378

Boron hydride polymer coated substrates  

DOEpatents

A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced into the chamber simultaneously with the generation of a plasma discharge within the chamber. A boron hydride plasma of ions, electrons and free radicals which is generated by the plasma discharge interacts to form a uniformly smooth boron hydride polymer which is deposited on the substrate.

Pearson, Richard K. (Pleasanton, CA); Bystroff, Roman I. (Livermore, CA); Miller, Dale E. (Livermore, CA)

1987-01-01

379

Boron hydride polymer coated substrates  

DOEpatents

A method is disclosed for coating a substrate with a uniformly smooth layer of a boron hydride polymer. The method comprises providing a reaction chamber which contains the substrate and the boron hydride plasma. A boron hydride feed stock is introduced into the chamber simultaneously with the generation of a plasma discharge within the chamber. A boron hydride plasma of ions, electrons and free radicals which is generated by the plasma discharge interacts to form a uniformly smooth boron hydride polymer which is deposited on the substrate.

Pearson, R.K.; Bystroff, R.I.; Miller, D.E.

1986-08-27

380

High-temperature cubic boron nitride p-N junction diode made at high pressure.  

PubMed

A p-n junction diode of cubic boron nitride was made by growing an n-type crystal epitaxially on a p-type seed crystal at a pressure of 55 kilobars and a temperature of about 1700 degrees C. A temperature-difference solvent method was used for the crystal growth, and beryllium and silicon were doped as acceptors and donors, respectively. Formation of the p-n junction was clearly confirmed at 1 bar by rectification characteristics and by existence of a space charge layer of the junction as observed by electron beam induced current measurement. This diode operated at 530 degrees C. PMID:17800457

Mishima, O; Tanaka, J; Yamaoka, S; Fukunaga, O

1987-10-01

381

Tadiran High Energy Lithium Batteries.  

National Technical Information Service (NTIS)

The electrical and environmental performance of a primary lithium inorganic battery is described as well as its reliability and safety features. The cell consists of a lithium anode, a carbon cathode, and a solution of lithium aluminum chloride in thionyl...

1977-01-01

382

Fabrication of boron sputter targets  

DOEpatents

A process for fabricating high density boron sputtering targets with sufficient mechanical strength to function reliably at typical magnetron sputtering power densities and at normal process parameters. The process involves the fabrication of a high density boron monolithe by hot isostatically compacting high purity (99.9%) boron powder, machining the boron monolithe into the final dimensions, and brazing the finished boron piece to a matching boron carbide (B.sub.4 C) piece, by placing aluminum foil there between and applying pressure and heat in a vacuum. An alternative is the application of aluminum metallization to the back of the boron monolithe by vacuum deposition. Also, a titanium based vacuum braze alloy can be used in place of the aluminum foil.

Makowiecki, Daniel M. (Livermore, CA); McKernan, Mark A. (Livermore, CA)

1995-01-01

383

Characterization of an ion trap to be used to determine the decay rate of ionized beryllium-7  

NASA Astrophysics Data System (ADS)

Beryllium-7 is an isotope with a 53-day half-life that decays exclusively by electron capture. The decay rate can be modified by changing the electron configuration, and the availability of electrons for capture. All previous measurements of the half-life were made with the Be-7 atoms embedded in a matrix of some kind that resulted in significant and not well characterized modifications to the electron configuration. We are building an ion trap to study the rate of decay of singly-ionized Be-7 to determine the rate when the electron configuration is well known. We are using a boron carbide plasma to characterize the behavior of the trap. The presence of boron-10, boron-11, and carbon-12 will also allow us to determine the resolution and sensitivity of the Fourier Transform Ion Cyclotron Resonance Mass Spectrometry technique that will be used to monitor the conversion of the Be-7 to Li-7 and to determine the half-life. The results of this characterization will be presented.

Peterson, Bryan G.; Erickson, Daniel; Hart, Grant W.

2009-11-01

384

Diffusion bonding of beryllium-copper alloys  

Microsoft Academic Search

A process has been developed for diffusion-bonding identical beryllium-copper alloy, 1.8 to 2.0 wt% Be, which has produced\\u000a bond strengths comparable to that of the bulk. Bonding resulted from self-diffusion between two Be-Cu samples, brought into\\u000a intimate contact and heated in a high vacuum. Metallurgical analyses of the diffusion bonds revealed the bond interface to\\u000a be a continuous high-angle planar

D. C. Eckman; B. Z. Rosenblum; C. Q. Bowles

1992-01-01

385

P-type doping of beryllium chalcogenides  

Microsoft Academic Search

In this contribution, we present first results on the p-type doping of beryllium-containing IIVI compounds such as BeTe, (BeMg)Te, (BeZn)Se and (BeMgZn)Se grown by molecular beam epitaxy (MBE) using a nitrogen plasma source. These materials are a very promising alternative to ZnSSe and MgZnSSe ternaries and quaternaries, respectively. The p-type dopability of (BeMg)Te:N as determined by means of van-der-Pauw measurements

H.-J. Lugauer; F. Fischer; T. Litz; A. Waag; U. Zehnder; W. Ossau; T. Gerhard; G. Landwehr; C. Becker; R. Kruse; J. Geurts

1997-01-01

386

ZIRCONIUM-TITANIUM-BERYLLIUM BRAZING ALLOY  

DOEpatents

A new and improved ternary alloy is described which is of particular utility in braze-bonding parts made of a refractory metal selected from Group IV, V, and VI of the periodic table and alloys containing said metal as a predominating alloying ingredient. The brazing alloy contains, by weight, 40 to 50 per cent zirconium, 40 to 50 per cent titanium, and the balance beryllium in amounts ranging from 1 to 20 per cent, said alloy having a melting point in the range 950 to 1400 deg C. (AEC)

Gilliland, R.G.; Patriarca, P.; Slaughter, G.M.; Williams, L.C.

1962-06-12

387

Lithium manganese oxides for rechargeable lithium batteries  

Microsoft Academic Search

Lithium manganese spinel compounds HT-LiMn2O4 (HT means high temperature) synthesized at > 700 C have high capacity in the 4 V range (LixMn2O4, x ? 1), However, lithium manganese oxides LT-LiMn2O4 (LT means low temperature) synthesized at temperatures lower than 400 C, resemble to the spinel structure and tend to have a reduced capacity in the 4 V range. We

Yoshiaki Nitta; Kazuhiro Okamura; Masatoshi Nagayama; Akira Ohta

1997-01-01

388

Exposure pathway assessment at a copper-beryllium alloy facility.  

PubMed

Controlling beryllium inhalation exposures to comply with regulatory levels (2 micro g m(-3) of air) does not appear to prevent beryllium sensitization and chronic beryllium disease (CBD). Additionally, it has proven difficult to establish a clear inhalation exposure-response relationship for beryllium sensitization and CBD. Thus, skin may be an important route of exposure that leads to beryllium sensitization. A 2000 survey had identified prevalence of sensitization (7%) and CBD (4%) in a beryllium alloy facility. An improved particulate migration control program, including dermal protection in production areas, was completed in 2002 at the facility. The purpose of this study was to evaluate levels of beryllium in workplace air, on work surfaces, on cotton gloves worn by employees over nitrile gloves, and on necks and faces of employees subsequent to implementation of the program. Over a 6 day period, we collected general area air samples (n = 10), wipes from routinely handled work surfaces (n = 252), thin cotton glove samples (n = 113) worn by employees, and neck wipes (n = 109) and face wipes (n = 109) from the same employees. In production, production support and office areas geometric mean (GM) levels of beryllium were 0.95, 0.59 and 0.05 micro g per 100 cm(2) on work surfaces; 42.8, 73.8 and 0.07 micro g per sample on cotton gloves; 0.07, 0.09 and 0.003 micro g on necks; and 0.07, 0.12 and 0.003 micro g on faces, respectively. Correlations were strong between beryllium in air and on work surfaces (r = 0.79), and between beryllium on cotton gloves and on work surfaces (0.86), necks (0.87) and faces (0.86). This study demonstrates that, even with the implementation of control measures to reduce skin contact with beryllium as part of a comprehensive workplace protection program, measurable levels of beryllium continue to reach the skin of workers in production and production support areas. Based on our current understanding of the multiple exposure pathways that may lead to sensitization, we support prudent control practices such as use of protective gloves to minimize skin exposure to beryllium salts and fine particles. PMID:16844720

Day, Gregory A; Dufresne, Andr; Stefaniak, Aleksandr B; Schuler, Christine R; Stanton, Marcia L; Miller, William E; Kent, Michael S; Deubner, David C; Kreiss, Kathleen; Hoover, Mark D

2006-07-14

389

Plasma boron and the effects of boron supplementation in males.  

PubMed Central

Recently, a proliferation of athletic supplements has been marketed touting boron as an ergogenic aid capable of increasing testosterone. The effect of boron supplementation was investigated in male bodybuilders. Ten male bodybuilders (aged 20 to 26) were given a 2.5-mg boron supplement, while nine male bodybuilders (aged 21 to 27) were given a placebo for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on day 1 and day 49 of the study. A microwave digestion procedure followed by inductively coupled argon plasma spectroscopy was used for boron determination. Twelve subjects had boron values at or above the detection limit with median value of 25 ng/ml (16 ng/ml lower quartile and 33 ng/ml upper quartile). Of the ten subjects receiving boron supplements, six had an increase in their plasma boron. Analysis of variance indicated no significant effect of boron supplementation on any of the other dependent variables. Both groups demonstrated significant increases in total testosterone (p < 0.01), lean body mass (p < 0.01), and one repetition maximum (RM) squat (p < 0.001) and one RM bench press (p < 0.01). The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser-trained bodybuilders, but boron supplementation affects these variables not at all.

Green, N R; Ferrando, A A

1994-01-01

390

Lithium ion cell safety  

Microsoft Academic Search

The safety characteristics of recent commercial lithium ion cells are examined in relation to their use for cellular phones. These are prismatic cells with an aluminum cell housing (can) and a 500600 mA h capacity. They have one of two types of 4-V class cathodes, lithium cobalt oxide (LiCoO2) or lithium manganese oxide (LiMn2O4). This report provides results of the

Shin-ichi Tobishima; Koji Takei; Yoji Sakurai; Jun-ichi Yamaki

2000-01-01

391

Lithium purification technique  

DOEpatents

A method for purifying liquid lithium to remove unwanted quantities of nitrogen or aluminum. The method involves precipitation of aluminum nitride by adding a reagent to the liquid lithium. The reagent will be either nitrogen or aluminum in a quantity adequate to react with the unwanted quantity of the impurity to form insoluble aluminum nitride. The aluminum nitride can be mechanically separated from the molten liquid lithium.

Keough, Robert F. (Richland, WA); Meadows, George E. (Richland, WA)

1985-01-01

392

Lithium purification technique  

DOEpatents

A method for purifying liquid lithium to remove unwanted quantities of nitrogen or aluminum. The method involves precipitation of aluminum nitride by adding a reagent to the liquid lithium. The reagent will be either nitrogen or aluminum in a quantity adequate to react with the unwanted quantity of the impurity to form insoluble aluminum nitride. The aluminum nitride can be mechanically separated from the molten liquid lithium.

Keough, R.F.; Meadows, G.E.

1984-01-10

393

Daily Boron Intake from the American Diet  

Microsoft Academic Search

Interest in boron as a naturally occurring trace element nutrient from the food supply is increasing. Mounting evidence suggests that boron is essential to human beings. This study explores the major food and beverage contributors of boron and estimates of daily boron intake from the American diet. Previous estimates in the literature of dietary boron consumption are based on limited

CHARLENE J RAINEY; LESLIE A NYQUIST; ROBERT E CHRISTENSEN; PHILIP L STRONG; B DWIGHT CULVER; JAMES R COUGHLIN

1999-01-01

394

Minerals Yearbook, 1992: Boron.  

National Technical Information Service (NTIS)

U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed be sales to textile-grade glass fibers, and soaps and detergents. California was the only d...

P. A. Lyday

1993-01-01

395

Minerals Yearbook, 1991: Boron.  

National Technical Information Service (NTIS)

U.S. production and sales of boron minerals and chemicals decreased during the year. Domestically, glass fiber insulation was the largest use for borates, followed by sales to textile-grade glass fibers, sales to distributors, and borosilicate glasses. Ca...

P. A. Lyday

1992-01-01

396

Wettability of Boron Carbide.  

National Technical Information Service (NTIS)

The work was presented at the conference, Advanced Joining Technologies from New Materials II, which was held in Cocoa Beach, USA, 2-4th of March. The conference proceedings will be published in 1994. The wettability of boron carbide has been examined by ...

T. Torvund O. M. Akselsen O. Grong J. H. Ulvensoen

1994-01-01

397

Sublimation of Boron.  

National Technical Information Service (NTIS)

Torsion-effusion and mass spectrometric techniques were used to study the vaporization of beta -rhombohedral boron over the temperature range 1823 to 2253 exp 0 K. The pressure-temperature data were fitted by the equation ln P(Pa) = -(66.8 +- 1.4) 10 exp ...

R. W. Mar R. G. Bedford

1976-01-01

398

Lithium batteries: Future batteries  

NASA Astrophysics Data System (ADS)

The main characteristics and applications of lithium batteries are reviewed. Miniature batteries for quartz crystal watches have been developed and fabricated in Switzerland since 1970. High technology systems like lithium batteries are largely used for their low auto-discharge during storage and for their high energy density. Two kinds of lithium batteries can be distinguished concerning their place in the watch: integrated batteries; and batteries placed between motion parts and the bottom of the watchcase. Lithium batteries are also used in pocket calculators, electronic modules for integrated circuits, telephone, control systems, electronic games, bank cards, and heart stimulators.

Reiche, Harald

399

The lithium-boron alloy anode in molten nitrate electrolytes  

Microsoft Academic Search

Potentiostatic studies of Li(B) anodes in molten LiNO at 300°C indicate that at 80% peak open-circuit voltage, a broad flat discharge at 780 mA cm⁻² is obtained. Galvanostatic discharge studies show stable anode potentials more negative than -3V (vs. Ag\\/sup +\\/\\/Ag) in LiNO at 300 mA cm⁻² over a temperature range of 270°⁻³⁵°sup 0\\/C. At temperatures above 350°C, deflagrations of

G. E. McManis; A. N. Fletcher; M. H. Miles

1984-01-01

400

Diamond ultraviolet photovoltaic cell obtained by lithium and boron doping  

SciTech Connect

Polycrystalline high quality freestanding 300-{mu}m-thick diamond films were doped by diffusion of B and Li under electric bias in order to fabricate vertical p-n junctions. Circular contacts were obtained by high dose ion implantation of B and Li. The I{endash}V characteristics were rectifying. When illuminated by deuterium lamp, an open circuit voltage was 2.6 eV. The shape of the I{endash}V characteristic under illumination points to the existence of shunt and series resistances. The obtained structure is most probably a p-n junction with bad contacts. {copyright} {ital 1997 American Institute of Physics.}

Popovici, G. [Nuclear Engineering Department, University of Missouri-Columbia, Columbia, Missouri 65211 (United States); Melnikov, A.; Varichenko, V.V. [Physics Department, Minsk State University, Minsk (Belarus); Sung, T.; Prelas, M.A. [Nuclear Engineering Department, University of Missouri-Columbia, Columbia, Missouri 65211 (United States); Wilson, R.G. [Hughes Research Laboratories, Malibu, California 90265 (United States); Loyalka, S.K. [Particulate Systems Research Center, University of Missouri-Columbia, Columbia, Missouri 65211 (United States)

1997-03-01

401

Thick beryllium coatings by magnetron sputtering  

SciTech Connect

Thick (>150 {micro}m) beryllium coatings are studied as an ablator material of interest for fusion fuel capsules for the National Ignition Facility (NIF). As an added complication, the coatings are deposited on mm-scale spherical substrates, as opposed to flats. DC magnetron sputtering is used because of the relative controllability of the processing temperature and energy of the deposits. We used ultra small angle x-ray spectroscopy (USAXS) to characterize the void fraction and distribution along the spherical surface. We investigated the void structure using a combination focused ion beam (FIB) and scanning electron microscope (SEM), along with transmission electron microscopy (TEM). Our results show a few volume percent of voids and a typical void diameter of less than two hundred nanometers. Understanding how the stresses in the deposited material develop with thickness is important so that we can minimize film cracking and delamination. To that end, an in-situ multiple optical beam stress sensor (MOSS) was used to measure the stress behavior of thick Beryllium coatings on flat substrates as the material was being deposited. We will show how the film stress saturates with thickness and changes with pressure.

Wu, H; Nikroo, A; Youngblood, K; Moreno, K; Wu, D; Fuller, T; Alford, C; Hayes, J; Detor, A; Wong, M; Hamza, A; van Buuren, T; Chason, E

2011-04-14

402

Spall fracture of beryllium under shockwave loading  

NASA Astrophysics Data System (ADS)

We present investigations of beryllium spall fracture with samples of dimensions 657 mm, which were made via vacuum hot pressing. Samples were loaded at normal incidence by a detonation wave of the explosive charge of TG 5/5 composition, 7, 14 and 30 mm in thickness, which gave shockwave stresses of 21-25 GPa within the sample. Spall fractures formed as the sample unloading at an air gap. A velocity profile was measured at the free boundary using VISAR laser interferometer, a spall layer thickness was measured with two-frame impulse X-ray radiography, and the shockwave profile was measured via a manganin-based gauge in a fluoroplastic base in the course of deceleration of a spall layer and of a basic part of beryllium. Hugoniot dynamic yield strength (YHE) and spall strength (?P) were measure as 0.69-0.73 GPa and 0.85+/-0.03 GPa, respectively, at a strain rate of ? ~104 s-1 in the unloading part of the incident pulse. A weak dependence between the spall layer thickness and HE layer thickness was recorded in tests. The weak dependence is not described through existing damage models and points to the need to develop more sophisticated models.

Skokov, Viktor; Arinin, Vladimir; Kryuchkov, Dmitry; Ogorodnikov, Vladimir; Raevsky, Viktor; Panov, Konstantin; Peshkov, Viktor; Tyupanova, Olga

2012-03-01

403

Identification of electron and hole traps in lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) crystals: Oxygen vacancies and lithium vacancies  

SciTech Connect

Electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) are used to identify and characterize electrons trapped by oxygen vacancies and holes trapped by lithium vacancies in lithium tetraborate (Li{sub 2}B{sub 4}O{sub 7}) crystals. Our study includes a crystal with the natural abundances of {sup 10}B and {sup 11}B and a crystal highly enriched with {sup 10}B. The as-grown crystals contain isolated oxygen vacancies, lithium vacancies, and copper impurities, all in nonparamagnetic charge states. During an irradiation at 77 K with 60 kV x-rays, doubly ionized oxygen vacancies trap electrons while singly ionized lithium vacancies and monovalent copper impurities trap holes. The vacancies return to their preirradiation charge states when the temperature of the sample is increased to approximately 90 K. Hyperfine interactions with {sup 10}B and {sup 11}B nuclei, observed between 13 and 40 K in the radiation-induced EPR and ENDOR spectra, provide models for the two vacancy-related defects. The electron trapped by an oxygen vacancy is localized primarily on only one of the two neighboring boron ions while the hole stabilized by a lithium vacancy is localized on a neighboring oxygen ion with nearly equal interactions with the two boron ions adjacent to the oxygen ion.

Swinney, M. W.; McClory, J. W.; Petrosky, J. C. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Yang Shan; Brant, A. T.; Halliburton, L. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Adamiv, V. T.; Burak, Ya. V. [Institute of Physical Optics, Dragomanov 23, L'viv 79005 (Ukraine); Dowben, P. A. [Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588 (United States)

2010-06-15

404

Health Consultation: Exposure Investigation Report. Beryllium Sensitivity Testing, Former American Beryllium Site, Tallevast, Manatee County, Florida. EPA Facility ID: FLD004100731, December 5, 2005.  

National Technical Information Service (NTIS)

This exposure investigation report summarizes blood collection procedures and beryllium sensitivity test results for 359 former American Beryllium workers, household members, and residents who live or previously lived in the nearby Tallevast community in ...

2005-01-01

405

Analysis of surface contaminants on beryllium and aluminum windows  

SciTech Connect

An effort has been made to document the types of contamination which form on beryllium window surfaces due to interaction with a synchrotron radiation beam. Beryllium windows contaminated in a variety of ways (exposure to water and air) exhibited surface powders, gels, crystals and liquid droplets. These contaminants were analyzed by electron diffraction, electron energy loss spectroscopy, energy dispersive x-ray spectroscopy and wet chemical methods. Materials found on window surfaces include beryllium oxide, amorphous carbon, cuprous oxide, metallic copper and nitric acid. Aluminum window surface contaminants were also examined.

Gmur, N.F.

1987-06-01

406

A Novel Biomarker for Beryllium Sensitization in Humans - Final Report  

SciTech Connect

This research project will determine the T-cell receptor (TCR) gene usages of beryllium reactive T-lymphocytes isolated directly from the peripheral blood of individuals exposed at a U.S. Department of Energy site. The objective is to develop a sensitive and novel biomarker for identifying early human sensitization to environmental beryllium. This is a collaborative project involving the Genetics Laboratory of the University of Vermont and both the Center for Epidemiological Research and the scientific staff of the Cytogenetics Program at the Oak Ridge Institute for Science and Education (ORISE). The > 2000 beryllium exposed workers who have been contacted for participation in the ORISE study ''Follow-up of Beryllium Workers at the Y-12 Plant/Efficacy of the Peripheral Blood Lymphocyte Proliferation (LPT) and other Non-Invasive Procedures for Diagnosis of Chronic Beryllium Disease'' will provide the pool of potential participants for the proposed study. Beryllium reactive T-lymphocytes will be directly isolated from peripheral blood using a novel antigen-independent method of surrogate selection for in vivo arising hprt mutants as representatives of clones that are undergoing chronic proliferation. The T-cells undergoing chronic proliferation in beryllium sensitized individuals will be enriched for beryllium reactive cells. The TCR gene usage of these T-cell isolates will be determined and their junctional (CDR3) regions sequenced. Beryllium reactive T-cell clones will also be recovered following in vitro beryllium stimulation of peripheral blood lymphocytes from these same individuals and the TCR gene CDR3 region sequences similarly determined. The TCR genes used by the beryllium reactive isolates and their CRD3 region sequences will be compared within (in vivo vs. in vitro derived) and among individuals with attention to kinds and durations of beryllium exposure and HPA DPB Glu 69 status. A method for quantitating total body loads of these antigen reactive T-cells in individuals will be developed using quantitative polymerase chain reaction (Q-PCR) amplification of specific TCR gene sequences. Successful achievement of this overall objective will permit future studies aimed at the elucidation of the immunological mechanisms underlying sensitization, the comparison of cells involved in pulmonary and systemic sensitization and the definition of potential targets for immunotherapy.

Albertini, R. J.

2001-04-16

407

Beryllium Health and Safety Committee Data Reporting Task Force  

SciTech Connect

On December 8, 1999, the Department of Energy (DOE) published Title 10 CFR 850 (hereafter referred to as the Rule) to establish a chronic beryllium disease prevention program (CBDPP) to: {sm_bullet} reduce the number of workers currently exposed to beryllium in the course of their work at DOE facilities managed by DOE or its contractors, {sm_bullet} minimize the levels of, and potential for, expos exposure to beryllium, and {sm_bullet} establish medical surveillance requirements to ensure early detection of the disease.

MacQueen, D H

2007-02-21

408

Introduction to the conference on beryllium-related diseases  

SciTech Connect

This issue of Environmental Health Perspectives Supplements includes papers presented at the Conference on Beryllium-related Diseases held November 8-10, 1994, at the National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina. Beryllium is the lightest of all solid and chemically stable substances and is used in some form in the aerospace, nuclear, telecommunications, and computer industries, as well as in ceramics, dental alloys, scientific equipment, automotive parts, and tool and die making. In the United States, it is estimated that there are approximately 8000 plants with 30,000 workers who may be potentially exposed to beryllium. 8 refs.

Jameson, C.W. [National Institute of Environmental Health Sciences, Research Triangle Park, NC (United States)

1996-10-01

409

Fuel-Rich Solid Propellant Boron Combustion.  

National Technical Information Service (NTIS)

Single particle boron ignition and combustion models developed in earlier phases of this program have been utilized and extended to treatment of boron cloud ignition, oxidizer depletion effects on cloud combustion time, laminar flame speeds in boron dust ...

J. Komar M. K. King R. S. Fry

1984-01-01

410

Boronated carbohydrate derivatives as potential boron neutron capture therapy reagents.  

PubMed

The treatment of cancer remains one of the most challenging problems for humanity. Boron neutron capture therapy is a binary approach for cancer treatment that is particularly attractive in treating high-grade gliomas and metastatic brain tumors. Among the types of boron-containing molecules used as boron neutron capture therapy agents, boronated carbohydrate derivatives have received significant attention because of their preferential uptake by growing tumor cells. This review provides a summary of the recent developments in the chemistry of carborane-containing carbohydrates. PMID:23617431

Marepally, Srinivasa R; Yao, Min-Liang; Kabalka, George W

2013-04-01

411

Using lithium safely.  

PubMed

Lithium is a difficult drug to use. Although it is effective in the management of mania, manic-depressive illness and recurrent depression, its unwanted effects are troublesome and the dose needs to be titrated against measurements of blood levels. With care, however, the risks can be minimized. Here we discuss lithium and approaches to optimize its use. PMID:10563060

1999-03-01

412

Lithium battery thermal models  

Microsoft Academic Search

Thermal characteristics and thermal behavior of lithium batteries are important both for the batteries meeting operating life requirements and for safety considerations. Sandia National Laboratories has a broad-based program that includes analysis, engineering and model development. We have determined thermal properties of lithium batteries using a variety of calorimetric methods for many years. We developed the capability to model temperature

Daniel H Doughty; Paul C Butler; Rudolph G Jungst; E. Peter Roth

2002-01-01

413

LITHIUM AND RENAL FUNCTIONS  

PubMed Central

SUMMARY Thirty patients of affective disorder who were on lithium for a year and thirty patients on antidepressant were studied in detail for renal functions. Our observation is that lithium therapy does not lead to any deterioration in kidney functions. The results are discussed.

Sethi, N.; Trivedi, J.K.; Sethi, B.B.

1987-01-01

414

Laminar Multicell Lithium Batteries  

SciTech Connect

Laminar batteries of series connected cells comprising lithium anodes and an electrolyte containing a passivating solvent reactive with lithium in which the cells are electrically connected in series by intercell barriers comprising outer layers of electrochemically inert electronically conducting material in contact with the electrochemically active anode and cathode of adjacent cells and a layer of metal foil between the electrochemically inert layers.

Bruder, A. H.

1984-01-31

415

Lithium Polymer Battery.  

National Technical Information Service (NTIS)

This report focuses on the development of a lithium-ion conducting channel as a solid-state electrolyte for rechargeable lithium batteries. Dilithium phthalocyanine (Li2Pc) has been used in this development since it can undergo molecular self-assembly to ...

L. G. Scanlon

2003-01-01

416

Mania pre-lithium.  

PubMed

The changes that lithium brought are most fully understood when we grasp the difficulties for management that acute mania presented. Restraint in canvas camisoles, padded cells, paraldehyde, water-baths and salts-Epsom, not Lithium-met mania in echos of Bedlam still heard in the early 1950s. It is a part of psychiatric history important to remember. PMID:10622174

Cawte, J

1999-12-01

417

High heat flux tests on beryllium and beryllium-copper joints  

Microsoft Academic Search

A large test program has been set up to evaluate the performance of beryllium as a plasma facing material for the divertor in thermonuclear fusion devices. Simulation of steady state heat loads of 5 MW m?2 and above on actively cooled divertor modules, and off-normal plasma conditions with energy densities in the range 17 MJ m?2, have been investigated. Thermal

M. Rdig; R. Duwe; J. Linke; A. Schuster

1997-01-01

418

Ion conductive characteristics of boron stabilized carbanion derived from organoboron ?-conjugated systems  

Microsoft Academic Search

Summary\\u000a Ion conductive properties of boron stabilized carbanions (BSC) have been studied as a model of ?-conjugated ion conductive\\u000a polymer in which counter anion of lithium ion is delocalized in ?-conjugated system. After treatment of the BSC precursor\\u000a (trimesitylborane or dimesityl-9-anthrylborane) with an organolithium reagent, the color of the reaction mixture dramatically\\u000a turned to dark red or purple. Interestingly, BSC

Noriyoshi Matsumi; Masahiro Nakashiba; Hiroyuki Ohno

2003-01-01

419

An improved neutron collimator for brain tumor irradiations in clinical boron neutron capture therapy  

Microsoft Academic Search

To improve beam penetration into a head allowing the treatment of deeper seated tumors, two neutron collimators were built sequentially and tested for use in the clinical boron neutron capture therapy (BNCT) program at the epithermal neutron irradiation facility of the Brookhaven Medical Research Reactor. The collimators were constructed from lithium-impregnated polyethylene, which comprises LiCO powder (93% enriched isotopic ⁶Li)

Hungyuan B. Liu; D. D. Greenberg; J. Capala; F. J. Wheeler

1996-01-01

420

Study about lithium battery's characteristics  

Microsoft Academic Search

To make certain the lithium battery's terminal limited discharge voltage and internal resistance in different load, four 3.2 V\\/60Ah lithium batteries are put in series to form battery pack in tests. The lithium battery pack terminal voltage, current and overall internal resistance were recorded with the discharge time. By analyze datas from the tests with MATLAB, the lithium battery pack

Ding Zuowu; Wang Shulin; Zhao Weijun; Qu Min

2010-01-01

421

Atmospheric corrosion of lithium electrodes  

Microsoft Academic Search

Atmospheric corrosion of lithium during lithium-cell assembly and the dry storage of cells prior to electrolyte fill has been found to initiate lithium corrosion pits and to form corrosion products. Scanning Electron Microscopy (SEM) was used to investigate lithium pitting and the white floccullent corrosion products. Electron Spectroscopy for Chemical Analysis (ESCA) and Auger spectroscopy in combination with X-ray diffraction

Johnson

1981-01-01

422

Cathode material for lithium batteries  

DOEpatents

A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

Park, Sang-Ho; Amine, Khalil

2013-07-23

423

Removing tritium and other impurities during industrial recycling of beryllium from a fusion reactor  

SciTech Connect

Recycling beryllium used in a fusion reactor might be a good way to overcome problems related to the disposal of neutron irradiated beryllium. The critical issues for the recycling of used first wall beryllium are the presence of tritium and (transuranic) impurities. High temperature annealing seems to be the most promising technique for detritiation. Purification of the de-tritiated beryllium can be achieved by chlorination of the irradiated beryllium and the subsequent reduction of beryllium chloride to highly pure metallic beryllium. After that, the beryllium can be re-fabricated into first wall tiles via powder metallurgy which is already a mature industrial practice. This paper outlines the path to define the experimental needs for beryllium recycling and tackles problems related to the detritiation and the purification via the chlorine route. (authors)

Dylst, K.; Seghers, J.; Druyts, F.; Braet, J. [SCK-CEN, Boeretang 200, 2400 Mol (Belgium)

2008-07-15

424

Hydrogen release from mixtures of lithium borohydride and lithium amide: a phase diagram study.  

PubMed

We recently reported the synthesis of a new quaternary hydride in the lithium-boron-nitrogen-hydrogen quaternary phase diagram with the approximate composition LiB0.33N0.67H2.67 having a theoretical hydrogen content of 11.9 wt %. This new compound forms by the reaction of appropriate amounts of lithium amide (LiNH2) and lithium borohydride (LiBH4) and releases greater than 10 wt % hydrogen when heated. A small amount of ammonia, 2-3 mol % of the generated gas, is also released. We now report a study of hydrogen and ammonia release from the series of reactant mixtures (LiNH2)x(LiBH4)1-x, where x=0.667 corresponds to the composition LiB0.33N0.67H2.67. We measured hydrogen and ammonia release amounts as a function of composition and found that maximum hydrogen and minimum ammonia release do occur for x=0.667. We also present evidence for an additional new quaternary phase and for two possibly metastable phases in this system. PMID:16509713

Meisner, Gregory P; Scullin, Matthew L; Balogh, Michael P; Pinkerton, Frederick E; Meyer, Martin S

2006-03-01

425

Lithium metal oxide electrodes for lithium batteries  

DOEpatents

An uncycled electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula Li.sub.(2+2x)/(2+x)M'.sub.2x/(2+x)M.sub.(2-2x)/(2+x)O.sub.2-.delta., in which 0.ltoreq.x<1 and .delta. is less than 0.2, and in which M is a non-lithium metal ion with an average trivalent oxidation state selected from two or more of the first row transition metals or lighter metal elements in the periodic table, and M' is one or more ions with an average tetravalent oxidation state selected from the first and second row transition metal elements and Sn. Methods of preconditioning the electrodes are disclosed as are electrochemical cells and batteries containing the electrodes.

Thackeray, Michael M. (Naperville, IL); Kim, Jeom-Soo (Naperville, IL); Johnson, Christopher S. (Naperville, IL)

2008-01-01

426

Boron nitride nanotubes  

Microsoft Academic Search

The successful synthesis of pure boron nitride (BN) nanotubes is reported here. Multi-walled tubes with inner diameters on the order of 1 to 3 nanometers and with lengths up to 200 nanometers were produced in a carbon-free plasma discharge between a BN-packed tungsten rod and a cooled copper electrode. Electron energy-loss spectroscopy on individual tubes yielded B:N ratios of approximately

N. G. Chopra; R. J. Luyken; K. Cherrey; V. H. Crespi; M. L. Cohen; S. G. Louie; A. Zettl

1995-01-01

427

Boron deficiency in maize  

Microsoft Academic Search

Boron (B) deficiency depresses wheat, barley and triticale yield through male sterility. On the basis of field responses to\\u000a B fertilization, maize (Zea mays L.) is affected by B deficiency in five continents. In a series of sand culture trials with maize subject to B0 (nil added\\u000a B) and B20 (20?M added B) treatments, we described how B deficiency depressed

Sittichai Lordkaew; Bernard Dell; Sansanee Jamjod; Benjavan Rerkasem

2011-01-01

428

Use of inductively coupled plasma-mass spectrometry in boron-10 stable isotope experiments with plants, rats, and humans.  

PubMed Central

The commercial availability of inductively coupled plasma-mass spectrometry technology (ICP-MS) has presented the opportunity to measure the boron concentrations and isotope ratios in a large number of samples with minimal sample preparation. A typical analytical sequence for fecal samples consists of 25 acid blanks, 1 digestion blank, 5 calibration solutions, 4 standard reference material solutions, 10 samples, and 4 natural abundance bias standards. Boron detection limits (3 x 1 sigma) for acid blanks are 0.11 ppb for 10B, and 0.40 ppb for 11B. Isotope ratios were measured in fecal samples with 20 to 50 ppb boron with < 2% relative standard deviation. Rapid washout and minimal memory effects were observed for a 50 ppb beryllium internal standard, but a 200 ppb boron biological sample had a 1.0 ppb boron memory after a 6-min washout. Boron isotope ratios in geological materials are highly variable; apparently this variability is reflected in plants of a fixed natural abundance value for boron requires that a natural abundance ratio be determined for each sample or related data set. The natural abundance variability also prevents quantitation and calculation of isotope dilution by instrument-supplied software. To measure boron transport in animal systems, 20 micrograms of 10B were fed to a fasted rat. During the 3 days after a 10B oral dose, 95% of the 10B was recovered from the urine and 4% from the feces. Urinary isotope ratios, 11B/10B, changed from a natural abundance of 4.1140 to an enriched value of 0.95077, a 77% change.(ABSTRACT TRUNCATED AT 250 WORDS)

Vanderpool, R A; Hoff, D; Johnson, P E

1994-01-01

429

Use of inductively coupled plasma-mass spectrometry in boron-10 stable isotope experiments with plants, rats, and humans.  

PubMed

The commercial availability of inductively coupled plasma-mass spectrometry technology (ICP-MS) has presented the opportunity to measure the boron concentrations and isotope ratios in a large number of samples with minimal sample preparation. A typical analytical sequence for fecal samples consists of 25 acid blanks, 1 digestion blank, 5 calibration solutions, 4 standard reference material solutions, 10 samples, and 4 natural abundance bias standards. Boron detection limits (3 x 1 sigma) for acid blanks are 0.11 ppb for 10B, and 0.40 ppb for 11B. Isotope ratios were measured in fecal samples with 20 to 50 ppb boron with < 2% relative standard deviation. Rapid washout and minimal memory effects were observed for a 50 ppb beryllium internal standard, but a 200 ppb boron biological sample had a 1.0 ppb boron memory after a 6-min washout. Boron isotope ratios in geological materials are highly variable; apparently this variability is reflected in plants of a fixed natural abundance value for boron requires that a natural abundance ratio be determined for each sample or related data set. The natural abundance variability also prevents quantitation and calculation of isotope dilution by instrument-supplied software. To measure boron transport in animal systems, 20 micrograms of 10B were fed to a fasted rat. During the 3 days after a 10B oral dose, 95% of the 10B was recovered from the urine and 4% from the feces. Urinary isotope ratios, 11B/10B, changed from a natural abundance of 4.1140 to an enriched value of 0.95077, a 77% change.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7889873

Vanderpool, R A; Hoff, D; Johnson, P E

1994-11-01

430

Design alternatives for cryogenic beryllium windows in an ICF cryostat  

SciTech Connect

We propose three backup design options for the cryogenic beryllium windows in a cryostat. The first, a beryllium flange option, reduces peak tensile stresses to 1/3 of that in the original design. The second, a fiberglass flange option, reduces peak tensile stresses to 1/2 of that in the original design and is also low cost. A third option, replacing the beryllium windows with spherical Mylar caps, would require a development program. Even though Mylar has been used previously at cryogenic temperature, this option is still considered unreliable. The near-zero ductility of beryllium at cryogenic temperature makes the reduction of peak tensile stresses particularly desirable. The orginal window design did function satisfactorily and the backup options were not needed. However, these options remain open for possible incorporation in future cryostat designs.

Pitts, J.H.; Landon, P.R.; Gerhard, M.A.

1984-11-01

431

High temperature chemical compatibility of beryllium for fusion reactor material.  

National Technical Information Service (NTIS)

International Thermonuclear Experimental Reactor (ITER) project plans to utilize beryllium as a plasma facing material, because of its prominent advantages such as low Z, substantial oxygen gettering effect and low tritium trapping in the process of redep...

H. Yoshida M. Okamoto O. Odawara T. Terai

1993-01-01

432

On chemical bonding and helium distribution in hcp beryllium  

NASA Astrophysics Data System (ADS)

The electron densities of states and spatial distribution of electron density in the system hcp beryllium-helium were investigated by means of ab-initio methods of simulation. It was found that contrary to predictions of the ``jelly'' model, the energetically more favorable configuration is that where a helium atom is located at the most restricted position, on a triangular face of two adjacent tetrahedrons, and where the charge density of electrons is maximal. It is established that this occurs due to hybridization of electron states of helium and nearest beryllium atom. The helium binding energy is about 5.6 eV. The spatial distribution of the charge density is investigated in details. Calculation of solution energy of helium in hcp beryllium was performed. The helium location at lattice sites in different interstitial positions and in divacancy complexes were considered. It is found that helium implemented into hcp beryllium favors formation of divacancies.

Bakai, A. S.; Timoshevskii, A. N.; Yanchitsky, B. Z.

2011-10-01

433

Determination of Total Beryllium in Soils by Atomic Absorption Spectrophotometry.  

National Technical Information Service (NTIS)

Methods of determining the total beryllium content in soil using atomic absorption spectrophotometry were considered, and a rather satisfactory method was adopted. This method was applied to 14 unpolluted soil samples. The results are outlined below: (1) ...

A. Teruo

1975-01-01

434

Effect of Inclusions on the Mechanical Behavior of Beryllium.  

National Technical Information Service (NTIS)

Samples of hot pressed and hot isostatically pressed S-65 beryllium were prepared from billets salted with iron base and graphite particles. Quasistatic tension, biaxial disc, and interally pressurized ring tests were performed to evaluate the effects of ...

D. B. King S. H. Gelles T. Nicholas

1976-01-01

435

Acute Toxicity of Beryllium Sulfate to Salamander Larvae ('Ambystoma spp').  

National Technical Information Service (NTIS)

The acute toxicity of beryllium sulfate to another class of organisms, the amphibians, was investigated using the same bioassay technique as reported previously with the guppies. The larvae of two species of salamanders (Ambystoma), which are usually larg...

A. R. Slonim E. E. Ray

1975-01-01

436

Status of knowledge about beryllium swelling by neutron irradiation.  

National Technical Information Service (NTIS)

The phenomenological aspects of swelling of beryllium subjected to neutronic irradiation and the relevant theoretical models are discussed. A comparison among the different proposed correlation and the available experimental data is made. The best fit is ...

C. Nardi

1991-01-01

437

Determination of Plutonium-Beryllium Source Strength by Manganese Activation.  

National Technical Information Service (NTIS)

In this study the manganese-sulfate-bath technique was used to determine the total neutron output of a Plutonium-Beryllium neutron source. Activation trials were conducted using 4 different concentrations of manganese sulfate and 3 different size containe...

P. F. Whitworth

1988-01-01

438

Determination of mu-amounts of beryllium in urine.  

PubMed

Methylene Blue and tannin are used to collect beryllium from urine by co-precipitation. After ignition the beryllium is brought into solution and determined fluorimetrically with Morin. When the amount of beryllium is less than 0.1 microg, measurements are carried out at low temperature to prevent fading of the fluorescence. In this method beryllium is collected and separated in a single step and no prior treatment of the urine sample is required either to destroy the organic matter or to remove the inorganic constituents present in it. The relative standard deviations for the determination of 0.1 and 0.02 microg of Be/100 ml of urine sample were 9 and 19% respectively. PMID:18960236

Desai, S R; Sudhalatha, K K

1967-11-01

439

Study of Complex Formation and Precipitation Conditions of Beryllium Hydroxide.  

National Technical Information Service (NTIS)

The percentage of beryllium present under the form of different complex ions is established. Three analytical concentrations taken with pH are observed. Data study results of equilibrium conditions of the different ions in solution are presented. (Atomind...

J. F. Oliveira M. M. A. El-Naggar

1984-01-01

440

Report of a technical evaluation panel on the use of beryllium for ITER plasma facing material and blanket breeder material.  

National Technical Information Service (NTIS)

Beryllium because of its low atomic number and high thermal conductivity, is a candidate for both ITER first wall and divertor surfaces. This study addresses the following: why beryllium; design requirements for the ITER divertor; beryllium supply and uni...

M. A. Ulrickson W. D. Manly D. E. Dombrowski

1995-01-01

441

20 CFR 30.206 - How does a claimant prove that the employee was a covered beryllium employee exposed to...  

Code of Federal Regulations, 2010 CFR

...claimant prove that the employee was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance...Eligibility Criteria for Claims Relating to Covered Beryllium Illness Under Part B of Eeoicpa §...

2009-04-01

442

20 CFR 30.206 - How does a claimant prove that the employee was a covered beryllium employee exposed to...  

Code of Federal Regulations, 2010 CFR

...claimant prove that the employee was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance...Eligibility Criteria for Claims Relating to Covered Beryllium Illness Under Part B of Eeoicpa §...

2010-04-01

443

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...  

Code of Federal Regulations, 2010 CFR

...What type of tort suits filed against beryllium vendors or atomic weapons employers...Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers...What type of tort suits filed against beryllium vendors or atomic weapons...

2010-04-01

444

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...  

Code of Federal Regulations, 2010 CFR

...What type of tort suits filed against beryllium vendors or atomic weapons employers...Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers...What type of tort suits filed against beryllium vendors or atomic weapons...

2009-04-01

445

20 CFR 30.206 - How does a claimant prove that the employee was a covered beryllium employee exposed to...  

Code of Federal Regulations, 2013 CFR

...claimant prove that the employee was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance...Eligibility Criteria for Claims Relating to Covered Beryllium Illness Under Part B of Eeoicpa §...

2013-04-01

446

20 CFR 30.507 - What compensation will be provided to covered Part B employees who only establish beryllium...  

Code of Federal Regulations, 2013 CFR

...Part B employees who only establish beryllium sensitivity under Part B of EEOICPA...Part B employees who only establish beryllium sensitivity under Part B of EEOICPA? The establishment of beryllium sensitivity does not entitle...

2013-04-01

447

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...  

Code of Federal Regulations, 2013 CFR

...What type of tort suits filed against beryllium vendors or atomic weapons employers...Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers...What type of tort suits filed against beryllium vendors or atomic weapons...

2013-04-01

448

Polarizabilities of the beryllium clock transition  

SciTech Connect

The polarizabilities of the three lowest states of the beryllium atom are determined from a large basis configuration interaction calculation. The polarizabilities of the 2s{sup 2} {sup 1}S{sup e} ground state (37.73a{sub 0}{sup 3}) and the 2s2p {sup 3}P{sub 0}{sup o} metastable state (39.04a{sub 0}{sup 3}) are found to be very similar in size and magnitude. This leads to an anomalously small blackbody radiation shift at 300 K of -0.018(4) Hz for the 2s{sup 2} {sup 1}S{sup e}-2s2p {sup 3}P{sub 0}{sup o} clock transition. Magic wavelengths for simultaneous trapping of the ground and metastable states are also computed.

Mitroy, J. [School of Engineering, Charles Darwin University, Darwin NT 0909 (Australia)

2010-11-15

449

Primordial Beryllium as a Big Bang Calorimeter  

SciTech Connect

Many models of new physics including variants of supersymmetry predict metastable long-lived particles that can decay during or after primordial nucleosynthesis, releasing significant amounts of nonthermal energy. The hadronic energy injection in these decays leads to the formation of {sup 9}Be via the chain of nonequilibrium transformations: Energy{sub h}{yields}T, {sup 3}He{yields}{sup 6}He, {sup 6}Li{yields}{sup 9}Be. We calculate the efficiency of this transformation and show that if the injection happens at cosmic times of a few hours the release of O(10 MeV) per baryon can be sufficient for obtaining a sizable {sup 9}Be abundance. The absence of a plateau structure in the {sup 9}Be/H abundance down to a O(10{sup -14}) level allows one to use beryllium as a robust constraint on new physics models with decaying or annihilating particles.

Pospelov, Maxim [Perimeter Institute for Theoretical Physics, Waterloo, Ontario, N2L 2Y5 (Canada)] [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, V8P 1A1 (Canada); Pradler, Josef [Perimeter Institute for Theoretical Physics, Waterloo, Ontario, N2L 2Y5 (Canada)

2011-03-25

450

First-Principles Thermoelasticity of Beryllium  

NASA Astrophysics Data System (ADS)

The temperature dependence ? of the shear modulus in beryllium is calculated using two different methods within the framework of Density Functional Theory. In Density Function Perturbation Theory, the usual technique to determine the values of elastic constants at T = 0 K is to access the temperature-dependence of the elastic constants through phonon calculations. The elastic constants are then combined to give the Voigt-Reuss-Hill shear modulus for each phase (hcp and bcc). In Quantum Molecular Dynamics, through a certainly crude assumption, we connect the ratio of mean square displacements at around melting temperature to the temperature-dependence of the shear modulus. With both techniques, we obtain ? = 0.24+/-0.14, in good agreement with the model of D. L. Preston and D. C. Wallace [Solid State Comm; 81 277 (1992)].

Legrand, Ph.; Robert, G.

2009-12-01

451

Primordial beryllium as a big bang calorimeter.  

PubMed

Many models of new physics including variants of supersymmetry predict metastable long-lived particles that can decay during or after primordial nucleosynthesis, releasing significant amounts of nonthermal energy. The hadronic energy injection in these decays leads to the formation of ?Be via the chain of nonequilibrium transformations: Energy(h)?T, He??He, ?Li??Be. We calculate the efficiency of this transformation and show that if the injection happens at cosmic times of a few hours the release of O(10 MeV) per baryon can be sufficient for obtaining a sizable ?Be abundance. The absence of a plateau structure in the ?Be/H abundance down to a O(10??) level allows one to use beryllium as a robust constraint on new physics models with decaying or annihilating particles. PMID:21517297

Pospelov, Maxim; Pradler, Josef

2011-03-23

452

Beryllium contamination and exposure monitoring in an inhalation laboratory setting.  

PubMed

Beryllium (Be) is used in several forms: pure metal, beryllium oxide, and as an alloy with copper, aluminum, or nickel. Beryllium oxide, beryllium metal, and beryllium alloys are the main forms present in the workplace, with inhalation being the primary route of exposure. Cases of workers with sensitization or chronic beryllium disease challenge the scientific community for a better understanding of Be toxicity. Therefore, a toxicological inhalation study using a murine model was performed in our laboratory in order to identify the toxic effects related to different particle sizes and chemical forms of Be. This article attempts to provide information regarding the relative effectiveness of the environmental monitoring and exposure protection program that was enacted to protect staff (students and researchers) in this controlled animal beryllium inhalation exposure experiment. This includes specific attention to particle migration control through intensive housekeeping and systematic airborne and surface monitoring. Results show that the protective measures applied during this research have been effective. The highest airborne Be concentration in the laboratory was less than one-tenth of the Quebec OEL (occupational exposure limit) of 0.15 microg/m(3). Considering the protection factor of 10(3) of the powered air-purifying respirator used in this research, the average exposure level would be 0.03 x 10(- 4) microg/m(3), which is extremely low. Moreover, with the exception of one value, all average Be concentrations on surfaces were below the Quebec Standard guideline level of 3 microg/100 cm(2) for Be contamination. Finally, all beryllium lymphocyte proliferation tests for the staff were not higher than controls. PMID:20056744

Muller, Caroline; Audusseau, Sverine; Salehi, Fariba; Truchon, Ginette; Chevalier, Gaston; Mazer, Bruce; Kennedy, Greg; Zayed, Joseph

2010-01-07

453

Performance of a Beryllium Copper Nonmagnetic Drill Collar Alloy  

Microsoft Academic Search

Laboratory characterization and extensive field service show the advantages of beryllium copper Brush Alloy 25 for use in nonmagnetic drill collars (NMDC)'s, stabilizers, and subs. Beryllium copper is resistant to stress-corrosion-cracking (SCC) failures at elevated temperatures and pressures in the presence of HS and dissolved chloride solutions. The alloy is more resistant than stainless steel to galling failure in threaded

F. Dunlevey

1986-01-01

454

Effect of electroslag remelting on the properties of beryllium bronze  

Microsoft Academic Search

1.The use of ESR for beryllium bronze eliminates resegregation, reduces the oxygen content, refines inclusions, and improves the ductility. This makes it possible to increase the annual output and to use greater reductions (~90%).2.After quenching and aging or MTT of beryllium bronze BNT1.9Mg melted by ESR the bronze has a higher elastic limit and relaxation resistance under conditions of cyclic

Zh. P. Pastukhova; A. G. Rakhshtadt; Yu. I. Zarembo; V. N. Kravchenko; V. P. Masyukov; L. I. Kachur

1979-01-01

455

Beryllium chalcogenides for ZnSe-based light emitting devices  

Microsoft Academic Search

Beryllium-containing ZnSe-based compound semiconductors introduce substantial additional degrees of freedom for the design of wide gap IIVI heterostructures. An overview of the advantages of beryllium chalcogenides is given here. A variety of BeTe-ZnSe and BeMgZnSe-ZnSe structures has been fabricated by molecular beam epitaxy, and their structural, optical and electrical properties have been investigated. The main aspects are the lattice matching

A. Waag; F. Fischer; H.-J. Lugauer; Th. Litz; T. Gerhard; J. Nrnberger; U. Lunz; U. Zehnder; W. Ossau; G. Landwehr; B. Roos; H. Richter

1997-01-01

456

Beryllium-containing materials for II-VI laser diodes  

Microsoft Academic Search

Beryllium containing ZnSe-based compound semiconductors introduce substantial additional degrees of freedom for the design of wide gap II-VI heterostructures. Interesting aspects are the lattice matching of BeTe with its high lying valence band and high p-type dopability for the growth of graded gap contacts capable of carrying high current densities, as well as the expected strengthening of quaternary beryllium compounds

Andreas Waag; Th. Litz; F. Fischer; H.-. Lugauer; Robert L. Gunshor; Gottfried Landwehr

1997-01-01

457

METHOD OF ALLOYING REACTIVE METALS WITH ALUMINUM OR BERYLLIUM  

DOEpatents

A halide of one or more of the reactive metals, neptunium, cerium and americium, is mixed with aluminum or beryllium. The mass is heated at 700 to 1200 deg C, while maintaining a substantial vacuum of above 10/sup -3/ mm of mercury or better, until the halide of the reactive metal is reduced and the metal itself alloys with the reducing metal. The reaction proceeds efficiently due to the volatilization of the halides of the reducing metal, aluminum or beryllium.

Runnalls, O.J.C.

1957-10-15

458

Structure and properties of beryllium bronze microalloyed with magnesium  

Microsoft Academic Search

1.The addition of a surface-active element (magnesium) increases the dispersity and uniformity of the structure, reducing the average grain size of the a-solid solution and the inclusions of excess plases in quenched beryllium bronzes.2.Microalloying of beryllium bronzes B2 and BNT1.9 with magnesium substantially improves their strength characteristics (elastic limit, relaxation resistance, cyclic strength) as the result of suppression of the

Kh. G. Tkhagapsoev; A. G. Rakhshtadt; Zh. P. Pastukhova; A. G. Karpov

1970-01-01

459

Helium and tritium retention and migration in beryllium  

Microsoft Academic Search

Efficiency of the application of beryllium for making such elements of ITER as neutron multiplicator, first wall coating and divertor plates depends on the helium and tritium mobility in this metal. Release parameters of helium and tritium from two grades of isotropic beryllium have been investigated after neutron irradiation at 550, 620, 780C with fluence of 2.61021 cm-2 3.5-1021 cm-2

I. B. Kuprianov; V. A. Gorokhov; V. V. Vlasov

1995-01-01

460

Helium-cooled, flibe breeder, beryllium multiplier blanket for MINIMARS  

Microsoft Academic Search

The helium-cooled, Flibe breeder blanket formed the basis for the Princeton Reference Design-the first, large, multidisciplinary fusion reactor design study. With this design, tritium breeding is submarginal, but adding beryllium corrects this problem. A large amount of beryllium in a zone of pebbles 0.5 m thick results in such a good breeder that the idea has formed the basis for

R. W. Moir; J. D. Lee

1986-01-01

461

Beryllium isotope geochemistry in tropical river basins  

SciTech Connect

The distributions of beryllium-9 and beryllium-10 in rivers within the Orinoco and Amazon basins have been examined to extend the understanding of their geochemical cycles and to develop their use both in geochronometry, and in studying erosional processes. Analyses of {sup 9}Be in dissolved and suspended material from rivers with a wide range of chemical compositions indicate that its geochemistry is primarily controlled by two major factors: (1) its abundance in the rocks of the watershed and (2) the extent of its adsorption onto particle surfaces. The relative importance of these parameters in individual rivers is determined by the extent of interaction with flood-plain sediments and the riverine pH. This understanding of {sup 9}Be geochemistry forms a basis for examination of the geochemical cycling of {sup 10}Be. In rivers which are dominated by interaction with sediments, the riverine concentration of dissolved {sup 10}Be is far lower than that in the incoming rainwater, indicating that a substantial proportion of it is retained within the soils of the basin or is adsorbed onto riverine particles. However, in acidic rivers in which the stable dissolved Be concentration is determined by the Be level in the rocks of the drainage basin, dissolved {sup 10}Be has essentially the same concentration as in precipitation. These observations imply that the soil column in such regions must be saturated with respect to {sup 10}Be, and that the ratio of the inventory to the flux does not represent an age, as may be the case in temperate latitudes, but rather a residence time.

Brown, E.T.; Edmond, J.M. (Massachusetts Inst. of Tech., Cambridge (United States)); Raisbeck, G.M.; Bourles, D.L.; Yiou, F. (Centre National de la Recherche Scientifique, Orsay (France)); Measures, C.I. (Univ. of Hawaii, Honolulu (United States))

1992-04-01

462

Method of fabricating boron containing coatings  

DOEpatents

Hard coatings are fabricated from boron nitride, cubic boron nitride, and multilayer boron/cubic boron nitride, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron is formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/cubic boron nitride, is produced by depositing alternate layers of boron and cubic boron nitride, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be discrete or of a blended or graded composition.

Makowiecki, Daniel M. (Livermore, CA); Jankowski, Alan F. (Livermore, CA)

1999-01-01

463

Determination of beryllium by using X-ray fluorescence spectrometry.  

PubMed

X-ray fluorescence spectrometry method is subject to certain difficulties and inconveniences for the elements having the atomic number 9 or less. These difficulties become progressively more severe as the atomic number decreases, and are quite serious for beryllium, which is practically indeterminable directly by XRF. Therefore, an indirect determination of beryllium that is based on the evaluation of cobalt in the precipitate is taken into consideration. In the thesis below, there is a description of a new, simple, and precise method by selective precipitation using hexamminecobalt(III) chloride and ammonium carbonate-EDTA solution as a complexing agent for the determining of a trace amount of beryllium using X-ray fluorescence spectrometry. The optimum conditions for [Co(NH(3))(6)][Be(2)(OH)(3)(CO(3))(2)(H(2)O)(2)].(3)H(2)O complex formation were studied. The complex was collected on the membrane filter, and the Co Kalpha line was measured by XRF. The method presents the advantages of the sample preparation and the elimination of the matrix effects due to the thin film obtained. The detection limit of the proposed method is 0.2 mg of beryllium. The method was successfully applied to beryllium determination in copper/ beryllium/cobalt alloys. PMID:18247483

Zawisza, Beata

2008-02-02

464

Beryllium pressure vessels for creep tests in magnetic fusion energy  

SciTech Connect

Beryllium has interesting applications in magnetic fusion experimental machines and future power-producing fusion reactors. Chief among the properties of beryllium that make these applications possible is its ability to act as a neutron multiplier, thereby increasing the tritium breeding ability of energy conversion blankets. Another property, the behavior of beryllium in a 14-MeV neutron environment, has not been fully investigated, nor has the creep behavior of beryllium been studied in an energetic neutron flux at thermodynamically interesting temperatures. This small beryllium pressure vessel could be charged with gas to test pressures around 3, 000 psi to produce stress in the metal of 15,000 to 20,000 psi. Such stress levels are typical of those that might be reached in fusion blanket applications of beryllium. After contacting R. Powell at HEDL about including some of the pressure vessels in future test programs, we sent one sample pressure vessel with a pressurizing tube attached (Fig. 1) for burst tests so the quality of the diffusion bond joints could be evaluated. The gas used was helium. Unfortunately, budget restrictions did not permit us to proceed in the creep test program. The purpose of this engineering note is to document the lessons learned to date, including photographs of the test pressure vessel that show the tooling necessary to satisfactorily produce the diffusion bonds. This document can serve as a starting point for those engineers who resume this task when funds become available.

Neef, W.S.

1990-07-20

465

METHOD OF MAKING ALLOYS OF BERYLLIUM WITH PLUTONIUM AND THE LIKE  

DOEpatents

The production of alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium are described. A halide salt of the metal to be alloyed with the beryllium is heated at 1300 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.

Runnals, O.J.C.

1959-02-24

466

METHOD OF MAKING ALLOYS OF BERYLLIUM WITH PLUTONIUM AND THE LIKE  

DOEpatents

The production or alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium is described. A halide salt or the metal to be alloyed with the beryllium is heated at l3O0 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.

Runnals, O.J.C.

1959-02-24

467

Binary compounds of boron and beryllium: a rich structural arena with space for predictions.  

PubMed

We explore ground-state structures and stoichiometries of the Be-B system in the static limit, with Be atom concentrations of 20?% or greater, and from P = 1?atm up to 320?GPa. At P = 1?atm, predictions are offered for several known compounds, the structures of which have not yet been determined experimentally. Specifically, at 1?atm, we predict a structure of R3m symmetry for the compound Be2B3, seen experimentally at high temperatures, which contains interesting BeBBBBe rods; and for the compound BeB4 we calculate metastability with respect to the elements with a structure similar to MgB4, which is quickly replaced as the pressure is elevated by a Cmcm structure that features 6- and 4-membered rings in B cages, with Be interstitials. For another high-temperature compound, Be2B, we confirm the CaF2 structure, but find a competitive and actually slightly more stable ground-state structure of C2/m symmetry that features B2 pairs. In the case of BeB2, a material for which the stoichiometry has been the subject of debate, we have a clear prediction of a stable F43m structure at P=1?atm. It has a diamondoid structure that is based on cubic (lower P) or hexagonal (higher P) diamond networks of B, but with Be in the interstices. This Zintl structure is a semiconductor at low and intermediate pressures. At higher pressures, BeB2 dominates the phase diagram. In general, the Zintl-Klemm concept of effective electron transfer from the more electropositive ion and bond formation among the resulting anions has proven useful in analyzing the structural preferences of many compositions in the Be-B system at P=1?atm and at elevated pressures. An unusual feature of this binary system is that the 1:1 BeB stoichiometry never appears to reach stability in the static limit, although it comes close, as does Be17B12. Also stable at high pressures are stoichiometries BeB3, BeB4, and Be5B2. PMID:23401125

Hermann, Andreas; Ashcroft, N W; Hoffmann, Roald

2013-02-11

468

Nuclear Magnetic Resonance Study of Uranium BERYLLIUM(13 - Boron(x)  

NASA Astrophysics Data System (ADS)

Nuclear magnetic resonance (NMR) measurements in the heavy fermion compound UBe_{13 -x}{B}_{x} for x = 0.030 and 0.067 in the temperature (T) range from 0.096 to 300 K are reported. Within a given sample we are able to detect resonances from three nuclei: ^9Be, ^{11}B, and ^{10}B. Analysis of the NMR spectra of these three nuclei show an exclusive substitution site for the B dopant into the m3 or cubic site of the UBe_{13} lattice. The nominal values of the B concentrations and a single phase sample composition is confirmed using NMR by a measurement of the relative number of ^{11}B to ^9Be nuclei in each sample. Normal state ^{11 }B magnetic shift (K_{m }) measurements exhibit the same T dependence as the static magnetic susceptibility(X_ {m}). From the slope of the linear plot of K_{m} verses X _{m}, the ^{11 }B hyperfine field (H_{hf }) is determined to be -361.1 Oe/mu_{B}. The magnetic shift is independent of B concentration. Normal state spin-lattice relaxation rate (1/T_1) measurements of ^{11} B as a function of T reveal two energy scales in the magnetic response of these materials. The T dependence of the normal state electronic fluctuation rate ( Gamma) of the U^{3+ } moments is calculated using the results of 1/T_1, X_{m}, and H_{hf} measurements. At T<2{K}, Gamma~1 meV for x = 0.030, which is in agreement with the width of the narrow feature in the density of states at the Fermi energy needed to give the large values of the low temperature electronic specific heat coefficient and magnetic susceptibility. At higher temperatures Gamma~sqrt{T} which is characteristic of isolated local moments. For T>60 K the occurrence of crystal field splittings introduce a second energy scale that destroys the sqrt{T} behavior. The results of Gamma for x = 0.030 are in quantitative agreement with quasi-elastic and inelastic neutron scattering measurements in UBe_{13}. We observe no evidence for antiferromagnetic spin correlations down to 2 K. The x = 0.067 sample shows a similar magnitude and T dependence of Gamma for T>10 K, but as Tto T_{c } Gamma(x = 0.030)/Gamma(0.067)~2. Below T_{c}~0.9 K the T dependence of 1/T_1 shows a strong B concentration dependence, especially at low temperatures. We interpret this behavior as consistent with gapless superconductivity induced by resonant scattering off the B impurities. The ratio of the ^9 Be to ^{11}B 1/{it T}_1 increases with decreasing temperature below T_{c} indicating additional contributions to the ^9Be relaxation rate, possibly from nuclear spin diffusion to normal-state vortex cores or paramagnetic impurities. The ^{11}B Knight shifts (K_{s}) for both sample concentrations are T independent below T_{c} with K_ {s} = -0.08+/-0.01%..

Ahrens, Eric Thomas

469

Beryllium and Boron Abundances of Metal-deficient Halo Stars and Accretion of Interstellar Matter  

Microsoft Academic Search

We discuss the correlation of light-element abundances with metallicity for metal-deficient dwarfs in the Galactic halo. We show that such stars can experience some metal enrichment after their formation because of accreting interstellar material during repeated encounters with molecular clouds in the Galactic plane. If light-element abundances are produced by the secondary spallation of preexisting heavy elements by cosmic rays,

Y. Yoshii; G. J. Mathews; T. Kajino

1995-01-01

470

Beryllium and Boron Abundances of Metal-deficient Halo Stars and Accretion of Interstellar Matter  

NASA Astrophysics Data System (ADS)

We discuss the correlation of light-element abundances with metallicity for metal-deficient dwarfs in the Galactic halo. We show that such stars can experience some metal enrichment after their formation because of accreting interstellar material during repeated encounters with molecular clouds in the Galactic plane. If light-element abundances are produced by the secondary spallation of preexisting heavy elements by cosmic rays, then this accretion affects the light-element abundances and metal abundances differently. We construct an analytic chemical evolution model for the halo and disk which reproduces the observed abundance correlations and the halo metallicity distribution. We show that the introduction of interstellar accretion leads to a low metallicity plateau in the correlation of light elements with metallicity which would mimic the formation of such elements in the big bang. We suggest here that the observation of a constant light-element abundance at low metallicity may not be a signature of primordial origin but rather a measure of the average accretion rate from metal-enriched gas in the Galactic plane.

Yoshii, Y.; Mathews, G. J.; Kajino, T.

1995-07-01

471

The Halo Nuclei BERYLLIUM-11 and BORON-8 Studied by Fragmentation Reactions.  

NASA Astrophysics Data System (ADS)

The discovery of anomalously large matter radii in some weakly bound nuclei on the neutron dripline has led to measurements of breakup fragment momentum distributions aimed at obtaining a qualitative understanding of these nuclei. The valence nucleons in halo nuclei penetrate the low barrier of the core potential, and form a diffuse layer around a normal sized core. Momentum distributions of core fragments following a direct breakup are related to the spatial distribution of the halo nucleon, via Fourier Transform, and offer a straightforward method to study halo nuclei. The momentum distribution in the direction parallel with the beam direction (p_{ |}) is less affected by reaction mechanism effects than the distribution perpendicular to the beam direction (p_{bot}), and is expected to most accurately reflect the halo neutron momentum wavefunction. The nucleus, ^{11}Be, has a one-neutron halo and core fragment momentum distributions should permit a simple determination of halo characteristics. We measured the p_{|} distribution of ^{10}Be core fragments in Be, Nb, Ta and U targets and found that the p_{|} distributions on all targets are in excellent agreement with a projection (onto the p| axis) of the momentum wavefunction of a 2s_{1/2} neutron bound by 500 keV in a Woods-Saxon potential. This is taken to indicate that reaction mechanism effects do not significantly influence the ^{10 }Be core fragment p_{| } distributions. The corresponding root-mean -square radius of the halo neutron is 6.5 fm. Finally, there is a controversy concerning the existence of a proton halo in ^8B. We approached the issue assuming that the p_ {|} distributions of ^7Be breakup fragments would reflect the spatial distribution of the valence proton, as we had shown for ^{11}Be. Both p _{|} and p_ {bot} were measured. The p _{|} distributions are narrow, but are only about half of the width of a prediction for a proton bound by 140 keV in a Woods-Saxon potential with a rms radius of 4.24 fm. In this case, it appears that for the smaller halo of the p-orbital proton the breakup momenta are influenced by both the nuclear and Coulomb reaction mechanism effects. When these effects are included, the predictions agree with the data.

Kelley, John Henry

472

The Halo Nuclei BERYLLIUM11 and BORON8 Studied by Fragmentation Reactions  

Microsoft Academic Search

The discovery of anomalously large matter radii in some weakly bound nuclei on the neutron dripline has led to measurements of breakup fragment momentum distributions aimed at obtaining a qualitative understanding of these nuclei. The valence nucleons in halo nuclei penetrate the low barrier of the core potential, and form a diffuse layer around a normal sized core. Momentum distributions

John Henry Kelley

1995-01-01

473

Occurrence model for volcanogenic beryllium deposits: Chapter F in Mineral deposit models for resource assessment  

USGS Publications Warehouse

Current global and domestic mineral resources of beryllium (Be) for industrial uses are dominated by ores produced from deposits of the volcanogenic Be type. Beryllium deposits of this type can form where hydrothermal fluids interact with fluorine and lithophile-element (uranium, thorium, rubidium, lithium, beryllium, cesium, tantalum, rare earth elements, and tin) enriched volcanic rocks that contain a highly reactive lithic component, such as carbonate clasts. Volcanic and hypabyssal high-silica biotite-bearing topaz rhyolite constitutes the most well-recognized igneous suite associated with such Be deposits. The exemplar setting is an extensional tectonic environment, such as that characterized by the Basin and Range Province, where younger topaz-bearing igneous rock sequences overlie older dolomite, quartzite, shale, and limestone sequences. Mined deposits and related mineralized rocks at Spor Mountain, Utah, make up a unique economic deposit of volcanogenic Be having extensive production and proven and probable reserves. Proven reserves in Utah, as reported by the U.S. Geological Survey National Mineral Information Center, total about 15,900 tons of Be that are present in the mineral bertrandite (Be4Si2O7(OH)2). At the type locality for volcanogenic Be, Spor Mountain, the tuffaceous breccias and stratified tuffs that host the Be ore formed as a result of explosive volcanism that brought carbonate and other lithic fragments to the surface through vent structures that cut the underlying dolomitic Paleozoic sedimentary rock sequences. The tuffaceous sediments and lithic clasts are thought to make up phreatomagmatic base surge deposits. Hydrothermal fluids leached Be from volcanic glass in the tuff and redeposited the Be as bertrandite upon reaction of the hydrothermal fluid with carbonate clasts in lithic-rich sections of tuff. The localization of the deposits in tuff above fluorite-mineralized faults in carbonate rocks, together with isotopic evidence for the involvement of magmatic water in an otherwise meteoric water-dominated hydrothermal system, indicate that magmatic volatiles contributed to mineralization. At the type locality, hydrothermal alteration of dolomite clasts formed layered nodules of calcite, opal, fluorite, and bertrandite, the latter occurring finely intergrown with fluorite. Alteration assemblages and elemental enrichments in the tuff and surrounding volcanic rocks include regional diagenetic clays and potassium feldspar and distinctive hydrothermal halos of anomalous fluorine, lithium, molybdenum, niobium, tin, and tantalum, and intense potassium feldspathization with sericite and lithium-smectite in the immediate vicinity of Be ore. Formation of volcanogenic Be deposits is due to the coincidence of multiple factors that include an appropriate Be-bearing source rock, a subjacent pluton that supplied volatiles and heat to drive convection of meteoric groundwater, a depositional site characterized by the intersection of normal faults with permeable tuff below a less permeable cap rock, a fluorine-rich ore fluid that facilitated Be transport (for example, BeF42- complex), and the existence of a chemical trap that caused fluorite and bertrandite to precipitate at the former site of carbonate lithic clasts in the tuff.

Foley, Nora K.; Hofstra, Albert H.; Lindsey, David A.; Seal, Robert R., II; Jaskula, Brian; Piatak, Nadine M.

2012-01-01

474

Effects of lithium counterdoping on radiation damage and annealing in n(+)p silicon solar cells  

SciTech Connect

Boron-doped silicon n(+)p solar cells were counterdoped with lithium by ion implantation and the resultant n(+)p cells irradiated by 1 MeV electrons. Performance parameters were determined as a function of fluence and a deep level transient spectroscopy (DLTS) study was conducted. The lithium counterdoped cells exhibited significantly increased radiation resistance when compared to boron doped control cells. Isochronal annealing studies of cell performance indicate that significant annealing occurs at 100 C. Isochronal annealing of the deep level defects showed a correlation between a single defect at E sub v + 0.43 eV and the annealing behavior of short circuit current in the counterdoped cells. The annealing behavior was controlled by dissociation and recombination of this defect. The DLTS studies showed that counterdoping with lithium eliminated three deep level defects and resulted in three new defects. The increased radiation resistance of the counterdoped cells is due to the interaction of lithium with oxygen, single vacancies and divacancies. The lithium-oxygen interaction is the most effective in contributing to the increased radiation resistance.

Weinberg, I.; Brandhorst, H.W. Jr.

1984-01-01

475

Radiation damage and defect behavior in ion-implanted, lithium counterdoped silicon solar cells  

SciTech Connect

Boron-doped silicon n/sup +/p solar cells were counterdoped with lithium by ion implantation and the resultant n/sup +/p cells irradiated by 1 MeV electrons. Performance parameters were determined as a function of fluence and a Deep Level Transient Spectroscopy (DLTS) study was conducted in order to correlate defect behavior with cell performance. It was found that the lithium counterdoped cells exhibited significantly increased radiation resistance when compared to boron doped control cells. Isochronal annealing studies of cell performance indicate that significant annealing occurs at 100/sup 0/C. Isochronal annealing of the deep level defects showed a correlation between a single defect at E /sub v+/ .43 eV and the annealing behavior of short circuit current in the counterdoped cells. It was concluded that the annealing behavior was controlled by dissociation and recombination of this defect. The DLTS studies also showed that counterdoping with lithium eliminated at least three deep level defects and resulted in three new defects. It was speculated that the increased radiation resistance of the counterdoped cells is due primarily to the interaction of lithium with oxygen, single vacancies and divacancies and that the lithium-oxygen interaction is the most effective in contributing to the increased radiation resistance.

Weinberg, I.; Mehta, S.; Swartz, C.K.

1984-05-01

476

Beryllium sensitization and disease among long-term and short-term workers in a beryllium ceramics plant  

Microsoft Academic Search

Objective: Workers at a beryllium ceramics plant were tested for beryllium sensitization and disease in 1998 to determine whether the\\u000a plant-wide prevalence of sensitization and disease had declined since the last screening in 1992; an elevated prevalence was\\u000a associated with specific processes or with high exposures; exposure-response relationships differed for long-term workers\\u000a hired before the last plant-wide screening and short-term

Paul K. Henneberger; Debra Cumro; David D. Deubner; Michael S. Kent; Michael McCawley; Kathleen Kreiss

2001-01-01

477

Beryllium-stimulated Release of Tumor Necrosis Factor a , Interleukin6, and Their Soluble Receptors in Chronic Beryllium Disease  

Microsoft Academic Search

Chronic beryllium disease (CBD) provides a model system in which to evaluate the antigen-stimu- lated, cell-mediated, immune response that leads to granulomatous lung disease. We hypothesized that beryllium salts would stimulate bronchoalveolar lavage (BAL) cell release of tumor necrosis fac- tor- a (TNF- a ) and interleukin-6 (IL-6), and their soluble receptors, soluble TNF receptor I (sTNF RI), sTNF RII,

SALLY S. TINKLE; LEE S. NEWMAN

478

Boron containing multilayer coatings and method of fabrication  

DOEpatents

Hard coatings are fabricated from multilayer boron/boron carbide, boron carbide/cubic boron nitride, and boron/boron nitride/boron carbide, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron and boron carbide used in forming the multilayers are formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/boron carbide, and boron carbide/cubic boron nitride is produced by depositing alternate layers of boron, cubic boron nitride or boron carbide, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be of a discrete or a blended or graded composition.

Makowiecki, Daniel M. (Livermore, CA); Jankowski, Alan F. (Livermore, CA)

1997-01-01

479

Combustion characteristics of boron nanoparticles  

Microsoft Academic Search

An experimental investigation of the combustion characteristics of boron nanoparticles in the post flame region of a flat flame burner has been conducted. Boron is attractive as a fuel or a fuel supplement in propellants and explosives due to its high heats of combustion on both a gravimetric and volumetric basis. A relatively large database exists for combustion characteristics of

Gregory Young; Kyle Sullivan; Michael R. Zachariah; Kenneth Yu

2009-01-01

480

Boron Clusters Come of Age  

ERIC Educational Resources Information Center

|Boron is the only element other than carbon that can build molecules of unlimited size by covalently boding to itself, a property known as catenation. In contrast to the chains and rings favored by carbon, boron arguably adopts a cluster motif that is reflected in the various forms of the pure element and in the huge area of polyhedral borane

Grimes, Russell N.

2004-01-01