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Sample records for beryllium 8 reactions

  1. Nitrogen reactivity toward beryllium: surface reactions.

    Science.gov (United States)

    Allouche, A

    2013-06-01

    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

  2. Technique of beryllium determination using an (α,n) reaction

    International Nuclear Information System (INIS)

    The possibility of detecting small amounts of 9Be using the (α, n) reaction has been investigated. It is shown that at a 210Po α-particle source intensity of 3x108 s-1 for limit of the detectable amount of beryllium is equal to 0.1 μg in the case of recording neutron-gamma (>= 3.6 MeV) coincidences. Other light elements (B, F, Al, Mg, Si etc.) do not produce a noticeable background under such conditions

  3. Proceedings of the 8th specialist meeting on recycling of irradiated Beryllium

    International Nuclear Information System (INIS)

    This report summarizes the documents presented in the 8th Specialist Meeting on Recycling of Irradiated Beryllium, which was held on October 28, 2013, in Bariloche, Río Negro, Argentina, hosted by INVAP and CNEA (Comision Nacional de Energia Atomica). The objective of the meeting is to exchange the information of current status and future plan for beryllium study in the Research/Testing reactors, and to make a discussion of “How to cooperate”. There were 20 participants from USA, Japan, Korea, Austria and Argentina. In this meeting, information exchange of current status and future plan for beryllium study was carried out for the Research/Testing reactor fields, and evaluation results of beryllium materials were discussed based on new irradiated beryllium data such as swelling, deformation, gas release and so on. The subject of the used beryllium recycling was also discussed for the enforcement of demonstration recycling tests. (author)

  4. Thermochemical study of gaseous oxy salts. Communication 8. Beryllium molybdate and tungstates

    International Nuclear Information System (INIS)

    Gaseous phase reactions involving beryllium molybdate and tungstates were studied by the method of high-temperature mass-spectroscopy. Standard formation enthalpies of BeMoO3, BeWO3, BeWO4 and Be2WO4 were determined, being equal to -432.4 ± 3.1, -424.1 ± 3.7, -794.9 ± 5.2, -973.4 ± 6.7 kJ/mol respectively. Atomization enthalpy of the salts at 298 K amounts to 2162 ± 5, 2347 ± 5, 2967 ± 7, 3470 ± 8 kJ/mol

  5. Beryllium allergy

    International Nuclear Information System (INIS)

    Beryllium is not only a high potent allergen, but also a fotoallergen and can provoke contact allergic reactions, fotoallergic reactions, granulomatous skin reactions, pulmonary granulomatous diseases and sometimes even systemic diseases. The authors present 9 own cases of a patch test positive beryllium allergy, 7 patients with relevant allergy and 5 patients with an allergic contact stomatitis. (author)

  6. Beryllium-steam interaction experiments and self-sustained reaction studies (integral validation testing)

    International Nuclear Information System (INIS)

    In accordance with the Task Agreement G 81 TT 02 FR, Be-steam interaction experiments were performed in order to obtain experimental data for validation of calculation codes analyzing accident situation involving water coolant ingress into the vacuum chamber of International Thermonuclear Experimental Reactor (ITER). The report describes the experimental facility, specimens used for oxidized beryllium emissivity factor determination and the ITER first wall mock-up used in the experiments on its interaction with steam. Experimental results on Be-emissivity factor after beryllium oxidation versus temperature are given. Four experimental runs of the ITER first wall mock-up interaction with steam were carried out for initial conditions when internal (beryllium) mock-up layer was heated to temperatures of 680, 880 and 1273 K and steam temperature was of 413-423 K. The plots of temperature evolution for beryllium, bronze and stainless steel layers versus time were obtained. Temperature records with 5 s interval are presented. Hydrogen gain in these four experimental runs was measured. The data may be used for computer code validation. No self-sustained Be-steam chemical reaction at temperatures used in the experiments was observed

  7. Density functional study of optical properties of beryllium chalcogenides compounds in nickel arsenide B8 structure

    International Nuclear Information System (INIS)

    The structural, electronic and optical properties of beryllium chalcogenides BeS, BeSe and BeTe using the full-potential linear augmented plane wave (FP-LAPW) method are investigated. The exchange-correlation energy within the local density approximation (LDA) and the generalized gradient approximation (GGA) are described. The Engel-Vosko (EVGGA) formalism is applied for electronic and optical properties. The structural parameters of our model and the transition pressure from zinc-blende (B3) to the NiAs (B8) phase are confirmed. It is found that these compounds have indirect band gaps except for BeTe in NiAs (B8) phase. The results of reflectivity, refractive index and optical dielectric functions of Be compounds are investigated. An agreement is found between our results and those of other theoretical calculations and the experimental data.

  8. Spectrophotometric determination of beryllium in air by a sensitised chrome azurol S reaction

    International Nuclear Information System (INIS)

    Although many spectrophotometric reagents for beryllium are known, their sensitivities do not approach that provided by the fluorimetric method using morin. A spectrophotometric method of comparable sensitivity is reported wherein addition of cetylpyridinium bromide considerably enhances the colour intensity of the beryllium - Chrome Azurol S complex. EDTA serves as a suitable masking agent for eliminating interferences from commonly associated ions. The results obtained are compared with those obtained with the morin method. Similar sensitisation of the beryllium - Chrome Azurol S system by polyoxyethylene dodecylamine and poly(vinyl alcohol) has been reported. (author)

  9. Halo effective field theory constrains the solar Beryllium-7 + proton -> Boron-8 + photon rate

    CERN Document Server

    Zhang, Xilin; Phillips, D R

    2015-01-01

    We report an improved low-energy extrapolation of the cross section for the process Beryllium-7+proton -> Boron-8+photon, which determines the Boron-8 neutrino flux from the Sun. Our extrapolant is derived from Halo Effective Field Theory (EFT) at next-to-leading order. We apply Bayesian methods to determine the EFT parameters and the low-energy S-factor, using measured cross sections and scattering lengths as inputs. Asymptotic normalization coefficients of Boron-8 are tightly constrained by existing radiative capture data, and contributions to the cross section beyond external direct capture are detected in the data at E < 0.5 MeV. Most importantly, the S-factor at zero energy is constrained to be S(0)= 21.3 + - 0.7 eV b, which is an uncertainty smaller by a factor of two than previously recommended. That recommendation was based on the full range for S(0) obtained among a discrete set of models judged to be reasonable. In contrast, Halo EFT subsumes all models into a controlled low-energy approximant, w...

  10. Beryllium nitride thin film grown by reactive laser ablation

    OpenAIRE

    G. Soto; Diaz, J.A.; Machorro, R.; Reyes-Serrato, A.; de la Cruz, W.

    2001-01-01

    Beryllium nitride thin films were grown on silicon substrates by laser ablating a beryllium foil in molecular nitrogen ambient. The composition and chemical state were determined with Auger (AES), X-Ray photoelectron (XPS) and energy loss (EELS) spectroscopies. A low absorption coefficient in the visible region, and an optical bandgap of 3.8 eV, determined by reflectance ellipsometry, were obtained for films grown at nitrogen pressures higher than 25 mTorr. The results show that the reaction ...

  11. An investigation of nuclear reactions useful for the detection of beryllium

    International Nuclear Information System (INIS)

    Nuclear techniques for the detection of trace element quantities of 9Be in environmental and biological samples have been investigated. A literature search has been made for suitable nuclear reactions using p, d, α, n and photons as incoming particles. The reactions 9Be(p,αγ)6Li, 9Be(d,nγ)10Be, 9Be(α,nγ)12C and 9Be(γ,n)8Be seems to be usable for 9Be concentrations in the order of ppm. Experimentally, the possibility 9Be(p,αγ)6Li has been tested at the resonance which occurs for Esub(p) = 2.567 MeV with a width of 39 keV and a cross-section of 110 mb. A Ge(Li) detector was used to detect the gamma-ray of energy 2.561 MeV for 6Li. Although the detection limit does not seem to be below 1 ppm for this reaction, it might be useful to establish an upper limit for the 9Be concentration in the range 1-20 ppm during conventional PIXE analyses just be monitoring the 3561 MeV gamma-ray in a suitable detector. (M.L.)

  12. How well do we understand Beryllium-7 + proton -> Boron-8 + photon? An Effective Field Theory perspective

    CERN Document Server

    Zhang, Xilin; Phillips, D R

    2015-01-01

    We have studied the 7Be(p,photon)8B reaction in the Halo effective field theory (EFT) framework. The leading order (LO) results were published in Phys.Rev.C89,051602(2014) after the isospin mirror process, 7Li(n,photon)8Li, was addressed in Phys.Rev.C89,024613(2014). In both calculations, one key step was using the final shallow bound state asymptotic normalization coefficients (ANCs) computed by ab initio methods to fix the EFT couplings. Recently we have developed the next-to-LO (NLO) formalism (to appear soon), which could reproduce other model results by no worse than 1% when the 7Be-p energy was between 0 and 0.5 MeV. In our recent report (arXiv:1507.07239), a different approach from that in Phys.Rev.C89,051602(2014) was used. We applied Bayesian analysis to constrain all the NLO-EFT parameters based on measured S-factors, and found tight constraints on the S-factor at solar energies. Our S(E=0 MeV)= 21.3 + - 0.7 eV b. The uncertainty is half of that previously recommended. In this proceeding, we provide...

  13. On the possibility of photometric determination of beryllium in the presence of aluminium by chromazurol S in aqua-organic media

    International Nuclear Information System (INIS)

    The possibility is shown to improve the selectivity of photometric determination of beryllium in the presence of aluminium using the reaction with Chromazurol S (CAS) in organo-aqueous solution and 8-hydroxyquinoline as masking agent. A mixture, containing propanol, 2-3 vol.% H2O and 1-2 vol.% acetic acid, is an optimal medium for the reaction betWeen beryllium and CAS. Determination of 0.45 μg of beryllium in the presence of 2000-fold amounts of aluminiUm is possible. Some other elements (mass excess is bracketed): nickel (7800) indium (2500), zink (700) do not hinder the reaction between beryllium and CAS

  14. Reactivity test between beryllium and copper

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, H. [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan); Kato, M. [NGK Insulators, Ltd., Aichi-ken (Japan)

    1995-09-01

    Beryllium has been expected for using as plasma facing material on ITER. And, copper alloy has been proposed as heat sink material behind plasma facing components. Therefore, both materials must be joined. However, the elementary process of reaction between beryllium and copper alloy does not clear in detail. For example, other authors reported that beryllium reacted with copper at high temperature, but it was not obvious about the generation of reaction products and increasing of the reaction layer. In the present work, from this point, for clarifying the elementary process of reaction between beryllium and copper, the out-of-pile compatibility tests were conducted with diffusion couples of beryllium and copper which were inserted in the capsule filled with high purity helium gas (6N). Annealing temperatures were 300, 400, 500, 600 and 700{degrees}C, and annealing periods were 100, 300 and 1000h. Beryllium specimens were hot pressed beryllium, and copper specimens were OFC (Oxygen Free Copper).

  15. HEINBE; the calculation program for helium production in beryllium under neutron irradiation

    International Nuclear Information System (INIS)

    HEINBE is a program on personal computer for calculating helium production in beryllium under neutron irradiation. The program can also calculate the tritium production in beryllium. Considering many nuclear reactions and their multi-step reactions, helium and tritium productions in beryllium materials irradiated at fusion reactor or fission reactor may be calculated with high accuracy. The calculation method, user's manual, calculated examples and comparison with experimental data were described. This report also describes a neutronics simulation method to generate additional data on swelling of beryllium, 3,000-15,000 appm helium range, for end-of-life of the proposed design for fusion blanket of the ITER. The calculation results indicate that helium production for beryllium sample doped lithium by 50 days irradiation in the fission reactor, such as the JMTR, could be achieved to 2,000-8,000 appm. (author)

  16. Beryllium Toxicity

    Science.gov (United States)

    ... Favorites Del.icio.us Digg Facebook Google Bookmarks Yahoo MyWeb Beryllium Toxicity Patient Education Care Instruction Sheet ... Favorites Del.icio.us Digg Facebook Google Bookmarks Yahoo MyWeb Page last reviewed: May 23, 2008 Page ...

  17. Defense programs beryllium good practice guide

    International Nuclear Information System (INIS)

    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 ampersand 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

  18. Compatibility test between beryllium and ferritic stainless steel(F82H)

    International Nuclear Information System (INIS)

    In a fusion blanket, beryllium has been identified for use as neutron multiplier, where it will be in contact with the structural material. Austenitic stainless steel, 316SS has been considered as the structural material. However, from some studies, it is reported that beryllium reacts with 316SS above 600 C. In our investigations, we found that the reaction product between beryllium and nickel, BeNi was formed on 316SS side at 600 C. Therefore, the compatibility between beryllium and ferritic stainless steel without nickel, F82H(Fe - 8%Cr - 2%W - 0.2%V) as the new structural material in JAERI was investigated to determine if it was more compatible with beryllium. In this study, for clarifying the chemical interaction between beryllium and F82H, the out-of-pile compatibility test has been carried out with diffusion couples of beryllium and F82H which were inserted in the capsule filled with high purity helium gas. Annealing temperatures was 400, 600 and 800 C, and annealing periods was 100, 300 and 1000 h, respectively. From the results of this test, it is obvious that the thickness of reaction layer in F82H is 2/3 of that in 316SS in the case of annealing at 800 C for 1000 h. (orig.)

  19. Method for welding beryllium

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

    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. Beryllium parts made using this method can be used as structural components in aircraft, satellites and space applications.

  20. Beryllium usage in fusion blankets and beryllium data needs

    International Nuclear Information System (INIS)

    Increasing numbers of designers are choosing beryllium for fusion reactor blankets because it, among all nonfissile materials, produces the highest number (2.5 neutron in an infinite media) of neutrons per 14-MeV incident neutron. In amounts of about 20 cm of equivalent solid density, it can be used to produce fissile material, to breed all the tritium consumed in ITER from outboard blankets only, and in designs to produce Co-60. The problem is that predictions of neutron multiplication in beryllium are off by some 10 to 20% and appear to be on the high side, which means that better multiplication measurements and numerical methods are needed. The n,2n reactions result in two helium atoms, which cause radiation damage in the form of hardening at low temperatures (300/degree/C). The usual way beryllium parts are made is by hot pressing the powder. A lower cost method is to cold press and then sinter. There is no radiation damage data on this form of beryllium. The issues of corrosion, safety relative to the release of the tritium built-up inside beryllium, and recycle of used beryllium are also discussed. 10 figs

  1. Method for welding beryllium

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-04-01

    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.

  2. Measurement of the neutron spectrum from the reaction of 30-MeV deuterons on a thick beryllium target

    International Nuclear Information System (INIS)

    Measurements were made of the neutron spectrum produced by bombarding a thick beryllium target with 30-MeV deuterons at the University of California, Davis cyclotron. This spectrum is of interest in studying the effect of neutrons on materials to be used in future fusion reactors. The spectrum was inferred from the activation of two sets of detector foils placed at 00 to the deuteron beam, one immediately behind the beryllium target block, and one 40 mm to the rear. A least-squares program was used to analyze the foil activation data to obtain the fluence in each of seven energy groups. The neutron spectrum (fluence/MeV) close to the target decreases continuously with energy in the range 5-32 MeV, while the spectrum 40 mm back has a peak at about 13 MeV. The contribution from neutrons of energies less than 10 MeV is much greater than that found in previous spectral measurements made at large distances from the target. This difference is attributed to the neutrons which are emitted at large angles from the deuteron beam. These observations show the importance of evaluating the neutron spectrum near the target if samples of materials are to be irradiated in this location

  3. Defense programs beryllium good practice guide

    Energy Technology Data Exchange (ETDEWEB)

    Herr, M.

    1997-07-01

    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

  4. Chronic Beryllium Disease

    Science.gov (United States)

    ... an immune response or “allergy” to beryllium metal, ceramic or alloy, termed beryllium sensitization (BeS). Beryllium sensitization occurs after ... Mroz MM, Newman LS. Beryllium disease screening in ceramics industry: Blood test ... at a metal, alloy and oxide production plant. Occup Environ Med 1997; ...

  5. Measurement of the production cross-section of positive pions in the collision of 8.9 GeV/c protons on beryllium

    CERN Document Server

    Catanesi, M G; Apollonio, M; Arce, P; Artamonov, A; Bagulya, A; Barr, G; Blondel, A; Bobisut, F; Bogomilov, M; Bonesini, M; Booth, C; Borghi, S; Bunyatov, S; Burguet-Castell, J; Buttar, C; Campanelli, M; Cervera-Villanueva, A; Chelkov, G A; Chernyaev, E; Chimenti, P; Chizhov, M; Coney, L; De Min, A; De Santo, A; Dedovitch, D; Di Capua, E; Dore, U; Dumarchez, J; Edgecock, R; Ellis, M; Engel, R; Ferri, F; Gastaldi, Ugo; Giani, S; Giannini, G; Gibin, D; Gilardoni, S; Gome-Cadenas, J J; Gorbunov, P; Gostkin, M I; Grant, A; Graulich, J S; Grichine, V; Grossheim, A; Gruber, P; Grégoire, G; Guglielmi, A M; Guskov, A; Gössling, C; Hodgson, P; Howlett, L; Ivanchenko, V; Kato, I; Kayis-Topaksu, A; Khartchenko, D; Kirsanov, M; Kolev, D; Koreshev, V; Krasnoperov, A V; Krumshtein, Z; Martín-Albo, J; Meurer, C; Mezzetto, M; Mills, G B; Morone, M C; Nefedov, Y; Novella, P; Orestano, D; Paganoni, M; Paleari, F; Palladino, V; Panman, J; Papadopoulos, I; Pasternak, J; Pastore, F; Pattison, C; Piperov, S; Polukhina, N; Popov, B; Prior, G; Radicioni, E; Robbins, S; Santin, G; Schmitz, D; Schroeter, R; Semak, A; Serdiouk, V; Soler, F J P; Sorel, M; Temnikov, P; Tereshchenko, V V; Tonazzo, A; Tornero, A; Tortora, L; Tsenov, R; Tsukerman, I; Vannucci, F; Veenhof, R; Vidal-Sitjes, G; Wiebusch, C; Zaets, V; Zhemchugov, A; Zuber, K; Zucchelli, P

    2007-01-01

    The double-differential production cross-section of positive pions, $d^2\\sigma^{\\pi^{+}}/dpd\\Omega$, measured in the HARP experiment is presented. The incident particles are 8.9 \\GeVc protons directed onto a beryllium target with a nominal thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96,000 reconstructable secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75~${GeV}/c$ $\\leq p_{\\pi} \\leq$ 6.5 ${GeV}/c$ and 30 mrad $\\leq \\theta_{\\pi} \\leq$ 210 mrad in the laboratory frame.

  6. Measurement of the production cross-section of positive pions in the collision of 8.9 GeV/c protons on beryllium

    Science.gov (United States)

    Catanesi, M. G.; HARP Collaboration; Radicioni, E.; Edgecock, R.; Ellis, M.; Robbins, S.; Soler, F. J. P.; Gößling, C.; Bunyatov, S.; Chelkov, G.; Dedovitch, D.; Gostkin, M.; Guskov, A.; Khartchenko, D.; Krasnoperov, A.; Kroumchtein, Z.; Nefedov, Y.; Popov, B.; Serdiouk, V.; Tereshchenko, V.; Zhemchugov, A.; di Capua, E.; Vidal-Sitjes, G.; Artamonov, A.; Arce, P.; Giani, S.; Gilardoni, S.; Gorbunov, P.; Grant, A.; Grossheim, A.; Gruber, P.; Ivanchenko, V.; Kayis-Topaksu, A.; Panman, J.; Papadopoulos, I.; Pasternak, J.; Tcherniaev, E.; Tsukerman, I.; Veenhof, R.; Wiebusch, C.; Zucchelli, P.; Blondel, A.; Borghi, S.; Campanelli, M.; Morone, M. C.; Prior, G.; Schroeter, R.; Engel, R.; Meurer, C.; Kato, I.; Gastaldi, U.; Mills, G. B.; Graulich, J. S.; Grégoire, G.; Bonesini, M.; de Min, A.; Ferri, F.; Paganoni, M.; Paleari, F.; Kirsanov, M.; Bagulya, A.; Grichine, V.; Polukhina, N.; Palladino, V.; Coney, L.; Schmitz, D.; Barr, G.; de Santo, A.; Pattison, C.; Zuber, K.; Bobisut, F.; Gibin, D.; Guglielmi, A.; Mezzetto, M.; Dumarchez, J.; Vannucci, F.; Ammosov, V.; Koreshev, V.; Semak, A.; Zaets, V.; Dore, U.; Orestano, D.; Pastore, F.; Tonazzo, A.; Tortora, L.; Booth, C.; Buttar, C.; Hodgson, P.; Howlett, L.; Bogomilov, M.; Chizhov, M.; Kolev, D.; Tsenov, R.; Piperov, S.; Temnikov, P.; Apollonio, M.; Chimenti, P.; Giannini, G.; Santin, G.; Burguet-Castell, J.; Cervera-Villanueva, A.; Gómez-Cadenas, J. J.; Martín-Albo, J.; Novella, P.; Sorel, M.; Tornero, A.

    2007-09-01

    The double-differential production cross-section of positive pions, d^2σ^{π+}/d pdΩ, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c≤pπ≤ 6.5 GeV/c and 30 mrad≤θπ≤ 210 mrad in the laboratory frame.

  7. Beryllium facilities in India

    International Nuclear Information System (INIS)

    Due to its unique combination of physical, mechanical, thermal and nuclear properties, beryllium is indispensable for many applications in the fields of nuclear and space sciences. Beryllia and copper beryllium alloys have also found extensive applications in the electrical and electronic industries. Beryllium facilities at Bhabha Atomic Research Centre (BARC) have been set up to meet indigenous requirements for these materials. Besides developing beryllium technology, the project team has also designed and developed a number of special purpose equipment. (Author)

  8. Neutron irradiation of beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Gelles, D.S.; Ermi, R.M. [Pacific Northwest National Lab., Richland, WA (United States); Tsai, H. [Argonne National Lab., IL (United States)

    1998-03-01

    Seven subcapsules from the FFTF/MOTA 2B irradiation experiment containing 97 or 100% dense sintered beryllium cylindrical specimens in depleted lithium have been opened and the specimens retrieved for postirradiation examination. Irradiation conditions included 370 C to 1.6 {times} 10{sup 22} n/cm{sup 2}, 425 C to 4.8 {times} 10{sup 22} n/cm{sup 2}, and 550 C to 5.0 {times} 10{sup 22} n/cm{sup 2}. TEM specimens contained in these capsules were also retrieved, but many were broken. Density measurements of the cylindrical specimens showed as much as 1.59% swelling following irradiation at 500 C in 100% dense beryllium. Beryllium at 97% density generally gave slightly lower swelling values.

  9. 2H induced reactions on 8Li and primordial nucleosynthesis

    International Nuclear Information System (INIS)

    Cross sections for the 8Li(d,n)9Be (ground state) and 8Li(d,t)7Li reactions, both important to primordial nucleosynthesis in the inhomogeneous models, have been measured using a radioactive beam technique. The cross section for the former reaction is found to be small, so it is important only for synthesis of 9Be. The cross section for the latter reaction, however, is found to be large enough to destroy significant quantities of 8Li, and thus could affect predictions of primordial nucleosynthesis yields

  10. Cryogenic Properties of Aluminum Beryllium and Beryllium Materials

    Science.gov (United States)

    Gamwell, Wayne R.; McGill, Preston B.

    2003-01-01

    Ultimate tensile strength, yield strength, and elongation were obtained for the aluminum-beryllium alloy, AlBeMetl62 (38%Al-62%Be), at cryogenic (-195.5 C (-320 F) and (-252.8 C) (-423 F)) temperatures, and for an optical grade beryllium, O-30H (99%Be), at -252.8 C. AlBeMetl62 material was purchased to the requirements of SAE-AMS7912, "Aluminum-Beryllium Alloy, Extrusions." O-30H material was purchased to the requirements of Brush Wellman Inc. specification O-30H Optical Grade Beryllium. The ultimate tensile and yield strengths for extruded AlBeMetl62 material increased with decreasing temperature, and the percent elongation decreased with decreasing temperature. Design properties for the ultimate tensile strength, yield strength, and percent elongation for extruded AlBeMetl62 were generated. It was not possible to distinguish a difference in the room and cryogenic ultimate strength for the hot isostatically pressed (HIP'ed) O-30H material. The O30H elongation decreased with decreasing temperature.

  11. Cryogenic Properties of Aluminum-Beryllium and Beryllium Materials

    Science.gov (United States)

    Gamwell, Wayne R.; McGill, Preston B.

    2003-01-01

    Ultimate tensile strength, yield strength, and elongation were obtained for the aluminum- beryllium alloy, AlBeMetl62 (38%Al-62%Be), at cryogenic (-195.5 C (-32O F) and (- 252.8 C) (-423 F)) temperatures, and for an optical grade beryllium, O-30H (99%Be), at -252.8 C. AlBeMet162 material was purchased to the requirements of SAE- AMs7912, "Aluminum-Beryllium Alloy, Extrusions". O-30H material was purchased to the requirements of Brush Wellman Inc. specification O-30H Optical Grade Beryllium. The ultimate tensile and yield strengths for extruded AlBeMet162 material increased with decreasing temperature, and the percent elongation decreased with decreasing temperature. Design properties for the ultimate tensile strength, yield strength, and percent elongation for extruded AlBeMetl62 were generated. It was not possible to distinguish a difference in the room and cryogenic ultimate strength for the hot isostatically pressed (HIP'ed) O-30H material. The O-30H elongation decreased with decreasing temperature.

  12. Beryllium chemistry and processing

    CERN Document Server

    Walsh, Kenneth A

    2009-01-01

    This book introduces beryllium; its history, its chemical, mechanical, and physical properties including nuclear properties. The 29 chapters include the mineralogy of beryllium and the preferred global sources of ore bodies. The identification and specifics of the industrial metallurgical processes used to form oxide from the ore and then metal from the oxide are thoroughly described. The special features of beryllium chemistry are introduced, including analytical chemical practices. Beryllium compounds of industrial interest are identified and discussed. Alloying, casting, powder processing, forming, metal removal, joining and other manufacturing processes are covered. The effect of composition and process on the mechanical and physical properties of beryllium alloys assists the reader in material selection. The physical metallurgy chapter brings conformity between chemical and physical metallurgical processing of beryllium, metal, alloys, and compounds. The environmental degradation of beryllium and its all...

  13. Cross sections and reaction rates of d+8Li reactions involved in Big Bang nucleosynthesis

    International Nuclear Information System (INIS)

    We have measured angular distributions of the 2H(8Li, 7Li)3H and 2H(8Li, 9Be)n reactions at Ec.m.=1.5 to 2.8 MeV using an 8Li-radioactive-beam technique. Astrophysical S-factors and reaction rates were calculated from the measured cross sections. Although the 2H(8Li, 9Be)n cross section is small, it can contribute to 9Be synthesis. The 2H(8Li, 7Li)3H reaction has a sufficiently large cross section to destroy 8Li, which may decrease the synthesis of heavier elements. No products from the 2H(8Li, 9Li)p reaction were detected. We also present the results of calculations using the inhomogeneous model of primordial nucleosynthesis in several regions of parameter space. ((orig.))

  14. [Reaction of 1,8-naphthyridine azides with ethyl acrylate].

    Science.gov (United States)

    Livi, O; Ferrarini, P L; Bertini, D; Tonetti, I

    1975-12-01

    The reaction of 1,8-naphthyridine azides with ethyl acrylate leads to the formation of 2-pyrazolines instead of 1,2,3-triazolines. Some of the compounds obtained have undergone pharmacological and microbiological (antibacterial) testing. PMID:1204828

  15. Beryllium. Evaluation of beryllium hydroxide industrial processes. Pt. 3

    International Nuclear Information System (INIS)

    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 Beryllium Co., Beryllium Corp., Murex Ltd., SAPPI) were selected as representative samples of diverse commercial processes in different countries. (Author)

  16. Thermal fatigue of beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Deksnis, E.; Ciric, D.; Falter, H. [JET Joint undertaking, Abingdon (United Kingdom)] [and others

    1995-09-01

    Thermal fatigue life of S65c beryllium castellated to a geometry 6 x 6 x (8-10)mm deep has been tested for steady heat fluxes of 3 MW/m{sup 2} to 5 MW/m{sup 2} and under pulsed heat fluxes (10-20 MW/m{sup 2}) for which the time averaged heat flux is 5 MW/m{sup 2}. These tests were carried out in the JET neutral beam test facility A test sequence with peak surface temperatures {le} 600{degrees}C produced no visible fatigue cracks. In the second series of tests, with T{sub max} {le} 750{degrees}C evidence for fatigue appeared after a minimum of 1350 stress cycles. These fatigue data are discussed in view of the observed lack of thermal fatigue in JET plasma operations with beryllium PFC. JET experience with S65b and S65c is reviewed; recent operations with {Phi} = 25 MW/m{sup 2} and sustained melting/resolidification are also presented. The need for a failure criterion for finite element analyses of Be PFC lifetimes is discussed.

  17. Reactions with the double-Borromean nucleus 8He

    International Nuclear Information System (INIS)

    Differential cross sections for elastic-scattering and neutron-transfer reactions along with cross sections for fusion in the 8He+65Cu system are reported at energies above the Coulomb barrier (Elab= 19.9 and 30.6 MeV). The present work demonstrates the feasibility of using inclusive measurements of characteristic in-beam γ rays with low-intensity (∼105 pps) radioactive ion beams to obtain the residue cross sections for fusion and neutron transfer. Exclusive measurements of γ rays in coincidence with light charged particles have been used to further characterize the direct reactions induced by this double-Borromean nucleus. Coupled reaction channels calculations are used to illustrate the important role played by the transfer channels and to help in understanding the influence of the structure of 8He on the reaction mechanism.

  18. Beryllium: genotoxicity and carcinogenicity

    International Nuclear Information System (INIS)

    Beryllium (Be) has physical-chemical properties, including low density and high tensile strength, which make it useful in the manufacture of products ranging from space shuttles to golf clubs. Despite its utility, a number of standard setting agencies have determined that beryllium is a carcinogen. Only a limited number of studies, however, have addressed the underlying mechanisms of the carcinogenicity and mutagenicity of beryllium. Importantly, mutation and chromosomal aberration assays have yielded somewhat contradictory results for beryllium compounds and whereas bacterial tests were largely negative, mammalian test systems showed evidence of beryllium-induced mutations, chromosomal aberrations, and cell transformation. Although inter-laboratory differences may play a role in the variability observed in genotoxicity assays, it is more likely that the different chemical forms of beryllium have a significant effect on mutagenicity and carcinogenicity. Because workers are predominantly exposed to airborne particles which are generated during the machining of beryllium metal, ceramics, or alloys, testing of the mechanisms of the mutagenic and carcinogenic activity of beryllium should be performed with relevant chemical forms of beryllium

  19. Theoretical Model Calculation for d + 8Li Reaction

    Institute of Scientific and Technical Information of China (English)

    HAN Yin-Lu; GUO Hai-Rui; ZHANG Yue; ZHANG Jing-Shang

    2008-01-01

    Based on the theoretical models for light nuclei, the calculations of reaction cross sections and the angular distributions for d+8Li reaction are performed. Since all of the particle emissions are from the compound nucleus to the discrete levels, the angular momentum coupling effect in pre-equilibrium mechanism is taken into account. The three-body break-up process and the recoil effect are involved. The theoretical calculated results are compared to existing experimental data.

  20. Spectrophotometric determination of beryllium with sulfochlorophenol S in organo-aqueous acetic-acid media

    International Nuclear Information System (INIS)

    The possibility has been shown of photometric determination of beryllium with sulphochlorophenol S using an acetic acid-propanol mixture (1:1), containing 0.5-1.5 vol% of water, as the reaction medium. Under such conditions, the reaction between beryllium and sulphochlorophenol S is sensitive and selective with respect to some easily hydrolized elements (Sn, Bi, Sb, Hg) as well as to Ga, In, Tl, Zn in the presence of HCl. The following excess amounts do not interfere with the determination of 0.45 μg Be: Hg-1.2x104, Sb-6.2x103, In-2.5x103, Tl-2.0x103, Zn-1.4x103, Ga-1.2x103. The reaction between beryllium and sulphochlorophenol S is selective with respect to a number of complexing agents. Beryllium can be determined in the presence of 150000-200000 times its weight amounts of tartaric, citric and boric acids, 5000-sulphosalycilic acid, 6000-oxalic acid, 6000-dimethyl glyoxime, 150-8-hydroxyquinoline

  1. Severe allergic hair dye reactions in 8 children

    DEFF Research Database (Denmark)

    Sosted, Heidi; Johansen, Jeanne Duus; Andersen, Klaus Ejner;

    2006-01-01

    Serious adverse skin reactions to permanent hair dyes and temporary black tattoos have been reported. As temporary tattoos have become fashionable among adolescents, the risk profile for p-phenylenediamine (PPD) sensitization of the population has changed simultaneously with an increasing use of...... hair dyes in this age group. This investigation reports PPD sensitization in children with regard to cause of sensitization, clinical presentation and consequences. Clinical history and patch test results for consecutive children below 16 years of age with suspected hair dye allergic reactions and...... positive patch tests to PPD were collected over 2 years in 2 Danish dermatology clinics. 8 children aged 12-15 years were collected, and they all reacted to several hair dye ingredients. 5 of the patients were hospitalized, 1 in the intensive care unit. 6 of the patients gave a history of prior reaction to...

  2. Beryllium Manufacturing Processes

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, A

    2006-06-30

    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

  3. Cluster reaction of [Ag8]-/[Cu8]- with chlorine: Evidence for the harpoon mechanism?

    Science.gov (United States)

    Luo, Zhixun; Berkdemir, Cüneyt; Smith, Jordan C.; Castleman, A. W.

    2013-09-01

    To examine the question whether the harpoon mechanism can account for the reactive behavior of microscopic charged systems, we have investigated the reactivity of coinage metal clusters in gas phase. Our studies reveal that the reactivity between [Cu8]-/[Ag8]- and chlorine gas is consistent with the harpoon mechanism. An increased reactive cross section is noted through our theoretical estimation based on two methods, ascribed to a long-range transfer of valence electrons from the [Cu8]-/[Ag8]- cluster to chlorine. Insights into this reactivity will be of interest to other researchers working on obtaining a better understanding of the reaction mechanisms of such superatomic species.

  4. Beryllium development programme in India

    International Nuclear Information System (INIS)

    India has fairly large deposits of beryl. The requirement of beryllium and copper-beryllium alloys in space and electronic industries has provided the incentive for the setting up of an indigenous base for the development of beryllium process metallurgy. The paper presents the developmental work carried out, in the Metallurgy Division of the Bhabha Atomic Research Centre, on the preparation of beryllium metal and its alloys starting from Indian beryl. A laboratory facility incorporating essential precautionary measures has been set up for the safe handling of beryllium and its compounds. Based on the laboratory investigations a flow-sheet suitable to Indian conditions has been developed. The flow-sheet involves preparation of anhydrous beryllium fluoride from beryl through the silico-fluoride route, magnesiothermic reduction of beryllium fluoride for the production of beryllium metal or its master alloy with copper or aluminium, and fabrication of beryllium metal. (author)

  5. Estimation of the tritium production and inventory in beryllium

    International Nuclear Information System (INIS)

    Beryllium has been proposed as a candidate material for the neutron multiplier in fusion blanket designs. Tritium will be produced and will accumulate in beryllium under neutron irradiation. The tritium production and inventories under 1.5 and 3.0GW fusion power operation were calculated for a layered pebble bed blanket with lithium oxide (Li2O) breeder and beryllium (Be) multiplier. Neutronics calculations were carried out using the one-dimensional transport code ANISN, and the tritium production due to direct reaction of 9Be(n,T)7Li and the two-step reactions 9Be(n,α)6Li(n,α)Twas taken into account. The tritium production due to the two-step reaction was calculated to be 50% of the total tritium production after 1 year full power operation (FPY). The tritium inventory was estimated by considering three kinetic parameters, the permeability from the breeder region, diffusivity in a beryllium matrix, and solubility. Tritium permeation from the breeder region to the beryllium region through a 316SS wall was as much as 3gh-1, which is 30% of the tritium production (9.6gh-1) in the breeder region. Using the diffusion coefficient of beryllium with no oxide layer on its surface, the total tritium inventory was calculated to be 7gFPY-1, mainly owing to solubility. The content of beryllium oxide significantly affects the effective diffusion coefficient. Using a diffusion coefficient for beryllium with beryllium oxide layer on its surface, the tritium inventory was found to be equal to the amount produced. (orig.)

  6. Detection of beryllium treatment of natural sapphires by NRA

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, P.C., E-mail: carolina.gutierrez@uam.e [Centro de Micro-Analisis de Materiales (CMAM), Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Ynsa, M.-D.; Climent-Font, A. [Centro de Micro-Analisis de Materiales (CMAM), Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Dpto. Fisica Aplicada C-12, Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Calligaro, T. [Centre de Recherche et de Restauration des musees de France C2RMF, CNRS-UMR171, 14 quai Francois Mitterrand, 75001 Paris (France)

    2010-06-15

    Since the 1990's, artificial treatment of natural sapphires (Al{sub 2}O{sub 3} crystals coloured by impurities) by diffusion of beryllium at high temperature has become a growing practice. This process permits to enhance the colour of these gemstones, and thus to increase their value. Detection of such a treatment - diffusion of tens of {mu}g/g of beryllium in Al{sub 2}O{sub 3} crystals - is usually achieved using high sensitivity techniques like laser-ablation inductively coupled plasma mass spectrometry (LA-ICP/MS) or laser-induced breakdown spectrometry (LIBS) which are unfortunately micro-destructive (leaving 50-100-{mu}m diameter craters on the gems). The simple and non-destructive alternative method proposed in this work is based on the nuclear reaction {sup 9}Be({alpha}, n{gamma}){sup 12}C with an external helium ion beam impinging on the gem directly placed in air. The 4439 keV prompt {gamma}-ray tagging Be atoms are detected with a high efficiency bismuth germanate scintillator. Beam dose is monitored using the 2235 keV prompt {gamma}-ray produced during irradiation by the aluminium of the sapphire matrix through the {sup 27}Al({alpha}, p{gamma}){sup 30}Si nuclear reaction. The method is tested on a series of Be-treated sapphires previously analyzed by LA-ICP/MS to determine the optimal conditions to obtain a peak to background appropriate to reach the required {mu}g/g sensitivity. Using a 2.8-MeV external He beam and a beam dose of 200 {mu}C, beryllium concentrations from 5 to 16 {mu}g/g have been measured in the samples, with a detection limit of 1 {mu}g/g.

  7. Detection of beryllium treatment of natural sapphires by NRA

    Science.gov (United States)

    Gutiérrez, P. C.; Ynsa, M.-D.; Climent-Font, A.; Calligaro, T.

    2010-06-01

    Since the 1990's, artificial treatment of natural sapphires (Al 2O 3 crystals coloured by impurities) by diffusion of beryllium at high temperature has become a growing practice. This process permits to enhance the colour of these gemstones, and thus to increase their value. Detection of such a treatment - diffusion of tens of μg/g of beryllium in Al 2O 3 crystals - is usually achieved using high sensitivity techniques like laser-ablation inductively coupled plasma mass spectrometry (LA-ICP/MS) or laser-induced breakdown spectrometry (LIBS) which are unfortunately micro-destructive (leaving 50-100-μm diameter craters on the gems). The simple and non-destructive alternative method proposed in this work is based on the nuclear reaction 9Be(α, nγ) 12C with an external helium ion beam impinging on the gem directly placed in air. The 4439 keV prompt γ-ray tagging Be atoms are detected with a high efficiency bismuth germanate scintillator. Beam dose is monitored using the 2235 keV prompt γ-ray produced during irradiation by the aluminium of the sapphire matrix through the 27Al(α, pγ) 30Si nuclear reaction. The method is tested on a series of Be-treated sapphires previously analyzed by LA-ICP/MS to determine the optimal conditions to obtain a peak to background appropriate to reach the required μg/g sensitivity. Using a 2.8-MeV external He beam and a beam dose of 200 μC, beryllium concentrations from 5 to 16 μg/g have been measured in the samples, with a detection limit of 1 μg/g.

  8. Status of beryllium study for fusion in RF

    International Nuclear Information System (INIS)

    The main directions of research activities in the field of beryllium application science and technology carried out in Russia during 2001-2003 have been reviewed. The main results of these investigations have been highlighted. First wall and port-limier. The investigation on the actively cooled components with beryllium cladding is under progress objecting on the clarification of their ultimate thermo cycling capabilities. The study of behavior of bulk beryllium and the boundary region of the contact with the cooling structure under the intensive thermo cycling loading and neutron irradiation have been the object of consideration in particular. The works on the optimization and modification of industrial fabrication processes for commercial scaled production of beryllium tile were also under way. The influence of neutron irradiation. The new experimental data on the nuclear properties of several Russian beryllium grades has been obtained. The samples have been subjected to the high neutron dozes. The influence of low temperature (70-200degree C) neutron irradiation on the thermal conductivity has been examined in particular. The interrelations of the helium inventory and temperature of neutron irradiation with tritium release out of irradiated beryllium samples have been analyzed. The beryllium associated safety questions. The experiments on the modeling of normal working conditions and conditions imitating the plasma disruption events in ITER performance scenario have been continued. The new experimental information on the coefficient of pulverization of beryllium and the accumulation of deuterium in beryllium under the action of proton beam has been collected. The dependence of the reaction rate constant for the beryllium oxidation by the water vapor for different conditions has been analyzed. The compact, porous and powder beryllium samples have been tested at the wide range of temperature, pressure and duration of reaction with water vapor. The calculating

  9. Gas retention in irradiated beryllium

    International Nuclear Information System (INIS)

    Helium (an inert gas) with low solubility in beryllium is trapped in irradiated beryllium at low temperatures (22 n/cm2 (E > 1 MeV). In these samples the calculated helium generated was ∼ 14,000 appm. They are described in terms of swelling, annealing, microstructure, and helium bubble behavior (size, density and mobility). A second sample was irradiated to ∼5 x 1022 n/cm2 (E > 1 MeV). In that one the calculated helium and tritium generated were ∼24,000 appm He and ∼3720 appm, and tritium content was examined in a dissolution experiment. Most of the tritium was released as gas to the glovebox indicating the generated tritium was retained in the helium bubbles. In a third set of experiments a specimen was examined by annealing at a succession of temperatures to more than 600 degree C for tritium release. In the temperature range of 300--500 degree C little release (0.01--0.4%) occurred, but there was a massive release at just over 600 degree C. Theories of swelling appear to adequately describe bubble behavior with breakaway release occurring at high helium contents and at large bubble diameters. 8 refs., 6 figs

  10. Beryllium Health and Safety Committee Data Reporting Task Force

    Energy Technology Data Exchange (ETDEWEB)

    MacQueen, D H

    2007-02-21

    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.

  11. The natural history of beryllium sensitization and chronic beryllium disease.

    OpenAIRE

    Newman, L. S.; Lloyd, J.; Daniloff, E.

    1996-01-01

    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 progressi...

  12. Reprocessing technology development for irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, H.; Sakamoto, N. [Oarai Research Establishment, Ibaraki-ken (Japan); Tatenuma, K. [KAKEN Co., Ibaraki-ken (Japan)] [and others

    1995-09-01

    At present, beryllium is under consideration as a main candidate material for neutron multiplier and plasma facing material in a fusion reactor. Therefore, it is necessary to develop the beryllium reprocessing technology for effective resource use. And, we have proposed reprocessing technology development on irradiated beryllium used in a fusion reactor. The preliminary reprocessing tests were performed using un-irradiated and irradiated beryllium. At first, we performed beryllium separation tests using un-irradiated beryllium specimens. Un-irradiated beryllium with beryllium oxide which is a main impurity and some other impurities were heat-treated under chlorine gas flow diluted with Ar gas. As the results high purity beryllium chloride was obtained in high yield. And it appeared that beryllium oxide and some other impurities were removed as the unreactive matter, and the other chloride impurities were separated by the difference of sublimation temperature on beryllium chloride. Next, we performed some kinds of beryllium purification tests from beryllium chloride. And, metallic beryllium could be recovered from beryllium chloride by the reduction with dry process. In addition, as the results of separation and purification tests using irradiated beryllium specimens, it appeared that separation efficiency of Co-60 from beryllium was above 96%. It is considered that about 4% Co-60 was carried from irradiated beryllium specimen in the form of cobalt chloride. And removal efficiency of tritium from irradiated beryllium was above 95%.

  13. Beryllium. Its minerals. Pt. 1

    International Nuclear Information System (INIS)

    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. Some of the most important beryllium ores, the Argentine emplacement of their deposits and world occurrence are described. Argentine and world production, resources and reserves are indicated here as well. (Author)

  14. Synthesis of Novel 5-(-Substituted-Anilino)-8-Hydroxyquinolines via Hartwig-Buchwald Amination Reaction

    Indian Academy of Sciences (India)

    Walaa A E Omar; Osmo E O Hormi

    2015-11-01

    Three novel 5-(-substituted-anilino)-8-benzyloxyquinoline derivatives were efficiently synthesized via Hartwig–Buchwald amination reaction. The new 5-(-substituted-anilino)-8-benzyloxyquinolines were reduced for 1–3 h to give the corresponding 5-(-substituted-anilino)-8-hydroxyquinolines. Extending the reduction reaction time to 7 h afforded the corresponding 1,2,3,4-tetrahydro-8-hydroxyquinoline derivatives.

  15. Joining of Beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, A

    2006-02-01

    A handbook dealing with the many aspects of beryllium that would be important for the users of this metal is currently being prepared. With an introduction on the applications, advantages and limitations in the use of this metal the following topics will be discussed in this handbook: physical, thermal, and nuclear properties; extraction from the ores; purification and casting of ingots; production and types of beryllium powders; consolidation methods, grades, and properties; mechanical properties with emphasis on the various factors affecting these properties; forming and mechanical working; welding, brazing, bonding, and fastening; machining; powder deposition; corrosion; health aspects; and examples of production of components. This report consists of ''Section X--Joining'' from the handbook. The prefix X is maintained here for the figures, tables and references. In this section the different methods used for joining beryllium and the advantages, disadvantages and limitations of each are presented. The methods discussed are fusion welding, brazing, solid state bonding (diffusion bonding and deformation bonding), soldering, and mechanical fastening. Since beryllium has a high affinity for oxygen and nitrogen with the formation of oxides and nitrides, considerable care must be taken on heating the metal, to protect it from the ambient atmosphere. In addition, mating surfaces must be cleaned and joints must be designed to minimize residual stresses as well as locations for stress concentration (notch effects). In joining any two metals the danger exists of having galvanic corrosion if the part is subjected to moisture or to any type of corroding environment. This becomes a problem if the less noble (anodic) metal has a significantly smaller area than the more noble (cathodic) metal since the ions (positive charges) from the anodic (corroding) metal must correspond to the number of electrons (negative charges) involved at the cathode. Beryllium

  16. Beryllium. Beryllium oxide, obtention and properties. Pt.4

    International Nuclear Information System (INIS)

    As a continuation of the 'Beryllium' series this work reviews several methods of high purity beryllia production. Diverse methods of obtention and purification from different beryllium compounds are described. Some chemical, mechanical and electrical properties related with beryllia obtention methods are summarized. (Author)

  17. Plasma spraying of beryllium and beryllium-aluminum-silver alloys

    International Nuclear Information System (INIS)

    A preliminary investigation on plasma-spraying of beryllium and a beryllium-aluminum 4% silver alloy was done at the Los Alamos National Laboratory's Beryllium Atomization and Thermal Spray Facility (BATSF). Spherical Be and Be-Al-4%Ag powders, which were produced by centrifugal atomization, were used as feedstock material for plasma-spraying. The spherical morphology of the powders allowed for better feeding of fine (<38 μm) powders into the plasma-spray torch. The difference in the as-deposited densities and deposit efficiencies of the two plasma-sprayed powders will be discussed along with the effect of processing parameters on the as-deposited microstructure of the Be-Al-4%Ag. This investigation represents ongoing research to develop and characterize plasma-spraying of beryllium and beryllium-aluminum alloys for magnetic fusion and aerospace applications

  18. SU-E-T-602: Beryllium Seeds Implant for Photo-Neutron Yield Using External Beam Therapy

    International Nuclear Information System (INIS)

    Purpose: To evaluate the Neutron yield obtained during prostate external beam irradiation. Methods: Neutrons, that are commonly a radiation safety concern for photon beams with energy above 10 MV, are induced inside a PTV from Beryllium implemented seeds. A high megavoltage photon beam delivered to a prostate will yield neutrons via the reaction Be-9(γ,n)2?. Beryllium was chosen for its low gamma,n reaction cross-section threshold (1.67 MeV) to be combined with a high feasible 25 MV photon beam. This beam spectra has a most probable photon energy of 2.5 to 3.0 MeV and an average photon energy of about 5.8 MeV. For this feasibility study we simulated a Beryllium-made common seed dimension (0.1 cm diameter and 0.5 cm height) without taking into account encapsulation. We created a 0.5 cm grid loading pattern excluding the Urethra, using Variseed (Varian inc.) A total of 156 seeds were exported to a 4cm diameter prostate sphere, created in Fluka, a particle transport Monte Carlo Code. Two opposed 25 MV beams were simulated. The evaluation of the neutron dose was done by adjusting the simulated photon dose to a common prostate delivery (e.g. 7560 cGy in 42 fractions) and finding the corresponding neutron dose yield from the simulation. A variance reduction technique was conducted for the neutrons yield and transported. Results: An effective dose of 3.65 cGy due to neutrons was found in the prostate volume. The dose to central areas of the prostate was found to be about 10 cGy. Conclusion: The neutron dose yielded does not justify a clinical implant of Beryllium seeds. Nevertheless, one should investigate the Neutron dose obtained when a larger Beryllium loading is combined with commercially available 40 MeV Linacs

  19. Technical Basis for PNNL Beryllium Inventory

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Michelle Lynn

    2014-07-09

    The Department of Energy (DOE) issued Title 10 of the Code of Federal Regulations Part 850, “Chronic Beryllium Disease Prevention Program” (the Beryllium Rule) in 1999 and required full compliance by no later than January 7, 2002. The Beryllium Rule requires the development of a baseline beryllium inventory of the locations of beryllium operations and other locations of potential beryllium contamination at DOE facilities. The baseline beryllium inventory is also required to identify workers exposed or potentially exposed to beryllium at those locations. Prior to DOE issuing 10 CFR 850, Pacific Northwest Nuclear Laboratory (PNNL) had documented the beryllium characterization and worker exposure potential for multiple facilities in compliance with DOE’s 1997 Notice 440.1, “Interim Chronic Beryllium Disease.” After DOE’s issuance of 10 CFR 850, PNNL developed an implementation plan to be compliant by 2002. In 2014, an internal self-assessment (ITS #E-00748) of PNNL’s Chronic Beryllium Disease Prevention Program (CBDPP) identified several deficiencies. One deficiency is that the technical basis for establishing the baseline beryllium inventory when the Beryllium Rule was implemented was either not documented or not retrievable. In addition, the beryllium inventory itself had not been adequately documented and maintained since PNNL established its own CBDPP, separate from Hanford Site’s program. This document reconstructs PNNL’s baseline beryllium inventory as it would have existed when it achieved compliance with the Beryllium Rule in 2001 and provides the technical basis for the baseline beryllium inventory.

  20. Beryllium coprecipitation with iron hydroxide

    International Nuclear Information System (INIS)

    Coprecipitation and sorption are studied of beryllium with hydroxide of Fe(3) in solutions of NH4NO3, KNO3, NH4HCO3, and H2O2 over a wide range of pH of the medium. The conditions are found for concentrating and separating beryllium from the carrier within definite ranges of pH of the medium

  1. Recoiled Proton Tagged Knockout Reaction for 8He

    Institute of Scientific and Technical Information of China (English)

    曹中鑫; 叶沿林; 江栋兴; 郑涛; 李智焕; 华辉; 葛榆成; 李湘庆; 楼建玲; 肖军; 李奇特; 吕林辉; 李阔昂; 王赫; 乔锐; 游海波; 陈瑞九

    2012-01-01

    An experiment for knockout reaction induced by SHe beam at 82.5 MeV/nucleon on CH2 and C targets was carried out. The 6He and 4He core fragments at forward angles and the recoiled protons at large angles were detected coincidently. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism are separated, which can be applied to the exclusive spectroscopic study on the structure of exotic nuclei.

  2. Temperaturabhängigkeit der Beryllium-Selbstdiffusion und des freien Volumens im metallischen Massivglas Zr46,8Ti8,2Cu7,5Ni10Be27,5

    OpenAIRE

    Rehmet, Achim

    2001-01-01

    Seit der Entwicklung von massiven metallischen Gläsern wie z.B. der hier untersuchten Legierung Zr46,8Ti8,2Cu7,5Ni10Be27,5 (V4) ist es möglich, an metallischen Systemen nicht nur den Glaszustand, sondern auch den unterkühlt-flüssigen Zustand zu untersuchen. Im ersten Teil dieser Arbeit wurde mit Hilfe der Radiotracer-Methode und unter Verwendung des Isotops 7Be die Temperaturabhängigkeit der Beryllium-Selbstdiffusion in der stark unterkühlten Zr46,8Ti8,2Cu7,5Ni10Be27,5-Schmelze bestimmt. Die ...

  3. Estimation on tritium production and inventory in beryllium

    International Nuclear Information System (INIS)

    Beryllium has been proposed as a candidate material for neutron multiplier on fusion blanket design, tritium will be produced and accumulated in beryllium during neutron irradiation. It is very important to estimate the tritium inventory on blanket design. Tritium production and inventory under 3.0 GW fusion power were calculated for the layered pebble bed blanket, with Li2O breeder and beryllium multiplier. Neutronics calculations were carried out by one-dimensional transport code, ANISN and tritium production was calculated by direct reaction of 9Be(n,T)7Li and two-step reactions of 9Be(n,α)6Li(n,α)T. At the position near first wall, the direct reaction occupied the majority of tritium production. However, at the position of the mid-depth, contribution of the two-step reaction was included the production from neutron slow down by beryllium itself. The ratio accounting for 50% of total tritium production of two-step reaction production over whole blanket for one year full power operation (FPY) was resulted

  4. Contribution to the study of the evolution of radiation induced He in Be O; Etudes sur l'evolution de l'helium produit par reactions nucleaires dans l'oxyde de beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Bareau, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-11-15

    The purpose of this work in-pile investigation of He formed by (n, 2n) and (n, {alpha}) nuclear reactions, released from irradiated BeO, in the temperature range 1000 - 1350 deg. C. The experimental results show that, for an instantaneous neutron fast flux of 10{sup 13} n cm{sup -2} sec{sup -1}, an equilibrium is attempted, after several days, for a part lower than 20 per cent of the quantity of He formed, theoretically calculated from the neutron cross sections of nuclear reactions, and from the analytical form of the neutron fast flux, releases from the solid. The validity of the values of calculated helium and the gas chromatographic analytical method are also verified by dissolution of the BeO pellets in cryolite. A new fast neutron flux measuring method may be so defined. The discussion of the experimental results enables to establish that the processus of He release is characterized by two phenomena: the first one which controls the release of He atoms out of the solid and the second which reveals a capture processus, connected to the irradiation and probably due to the vacancies induced in the lattice. (author) [French] On etudie en pile le degagement de l'helium forme par reactions nucleaires (n, 2 n) et (n, {alpha}) dans l'oxyde de beryllium irradie entre 1000 et 1350 deg. C. Les resultats experimentaux montrant que, pour un flux rapide instantane de 10{sup 13} n{sub r} cm{sup -2} s{sup -1}, on aboutit, au bout de quelques jours, a un etat d'equilibre pour lequel une partie, inferieure a 20 pour cent de la quantite d'helium forme, calculee theoriquement a partir des sections efficaces des reactions nucleaires et de la forme analytique du flux rapide, s'echappe du solide. On verifie egalement par dissolution des echantillons de BeO dans la cryolithe la validite du calcul de l'helium et de la methode de dosage par chromatographie en phase gazeuse. On peut ainsi definir une methode nouvelle de mesure des flux rapides. La

  5. Characterization of shocked beryllium

    International Nuclear Information System (INIS)

    Explosively driven arrested beryllium experiments were performed with post mortem characterization to evaluate the failure behaviors. The test samples were encapsulated in an aluminum assembly that was large relative to the sample, and the assembly features both axial and radial momentum traps. The sample carrier was inserted from the explosively-loaded end and has features to lock the carrier to the surrounding cylinder using the induced plastic flow. Calculations with Lagrangian codes showed that the tensile stresses experienced by the Be sample were below the spall stress. Metallographic characterization of the arrested Be showed radial cracks present in the samples may have been caused by bending moments. Fractography showed the fractures propagated from the side of the sample closest to the explosives, the side with the highest tensile stress. There was evidence that the fractures may have propagated from the circumferential crack outward and downward radially.

  6. Multiplex polymerase chain reaction (PCR) on a SU-8 chip

    DEFF Research Database (Denmark)

    Christensen, Troels Balmer; Bang, Dang Duong; Wolff, Anders

    2008-01-01

    We present the detection of Campylobacter at species level using multiplex PCR in a micro fabricated PCR chip. The chip is based on the polymer SU-8 that allows integration with different microfluidic components, e.g., sample pre-treatment before PCR, and DNA detection simultaneously with or after...... the PCR. The chip performs very well with respect to heating and cooling rates with values up to around 40 °C/s and 20 °C/s, respectively, and has low power consumption (0.5–2.5 W depending on temperature). Multiplex DNA amplification by PCR for the detection of Campylobacter at species level...... was performed successfully on the chip with results comparable to conventional PCR methods. Microsystems often show serious PCR inhibition due to a high surface to volume ratio which causes an increased proclivity of the PCR mix ingredients to stick to the surfaces. To avoid this, a simple method of dynamic...

  7. Investigation of activation behind a beryllium slab under irradiation with 14 MeV neutrons

    International Nuclear Information System (INIS)

    Some concepts of a thermonuclear blanket include a neutron multiplier whose purpose is to breed tritium. The best neutron-multiplier is beryllium because the cross section (550 mb) of the (n,2n) reaction is large and the threshold energy (2.7 MeV) is low. The accuracy of the prediction of the tritium ratio depends strongly on the uncertainty of its (n,2n) reaction cross section. It is thus extremely important to check the consistency of the estimated data for beryllium, which are employed in theoretical investigations. The experimental results for beryllium assemblies disagree with the computational data. This makes it necessary to perform new experiments

  8. Experimental study to explore the 8Be-induced nuclear reaction via the Trojan horse method

    Science.gov (United States)

    Wen, Qun-Gang; Li, Cheng-Bo; Zhou, Shu-Hua; Irgaziev, Bakhadir; Fu, Yuan-Yong; Spitaleri, Claudio; La Cognata, Marco; Zhou, Jing; Meng, Qiu-Ying; Lamia, Livio; Lattuada, Marcello

    2016-03-01

    To explore a possible indirect method for 8Be induced astrophysical reactions, the 8Be=(8Be+n ) cluster structure has been studied via the Trojan horse method. For the first time a 8Be nucleus having an ultrashort lifetime is studied by the Trojan horse method and a 9Be nucleus in the ground state is used for this purpose. The 9Be nucleus is assumed to have a (8Be+n ) cluster structure and used as a Trojan horse nucleus. The 8Be nucleus acts as a participant, while the neutron is a spectator to the virtual 8Be+d →α +6Li reaction via the 3-body reaction 8Be+d →α +6Li+n . The experimental neutron momentum distribution inside 9Be has been reconstructed. The agreement between the experimental momentum distribution and the theoretical one indicates that a (8Be+n ) cluster structure inside 9Be is very likely. Therefore, the experimental study of 8Be induced reactions, for example, the measurement of the 8Be+α →12C reaction proceeding through the Hoyle state, is possible.

  9. Charge exchange cross sections for the reaction Xe+8 + Xe+8 → Xe+9 + Xe+7

    International Nuclear Information System (INIS)

    The charge changing cross sections for self collisions of Xe+8 ions with 0 to 150 keV relative translational kinetic energy are estimated on the basis of the Fano-Lichten electron promotion model. It is concluded that for Xe+8 + Xe+8, charge changing collisions occur only infrequently compared to excitation and with cross sections much smaller than 10-18 cm2

  10. Preparation of copper-beryllium alloys from Indian beryl

    International Nuclear Information System (INIS)

    The report presents the results of laboratory scale investigations on the preparation of copper-beryllium and aluminium-beryllium master alloys starting from Indian beryl and adopting the fluoride process. The flow-sheet involves : (1) conversion of the Be-values in beryl into water soluble sodium beryllium fluoride (2) preparation of beryllium hydroxide by alkali treatment of aqueous Na2BeF4 (3) conversion of Be(OH)2 to (NH4)2BeF4 by treatment with NH4HF2 (4) thermal decomposition of (NH4)2BeF4 to BeF2 and (5) magnesium reduction of BeF2 (with the addition of copper/aluminium) to obtain beryllium alloys. The method has been successfully employed for the preparation of Cu-Be master alloys containing about 8% Be and free of Mg on a 200 gm scale. An overall Be-recovery of about 80% has been achieved. Al-8% Be master alloys have also been prepared by this method. Toxicity and health hazards associated with Be are discussed and the steps taken to ensure safe handling of Be are described. (author)

  11. Indirect measurements of the solar-neutrino production reaction 7Be(p,γ)8B

    International Nuclear Information System (INIS)

    Low-energy cross sections of the 7Be(p,γ)8B reaction is of crucial importance, because they determine the high-energy solar neutrino flux. Coulomb dissociation with intermediate-energy 8B beams and low-energy proton-transfer reactions with 7Be beams have been investigated to determine indirectly the astrophysical S17 factors of the 7Be(p,γ)8B reaction. The results of these studies are generally in good agreement with the ones obtained by direct capture measurements using intense proton beams and radioactive 7Be targets

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

    International Nuclear Information System (INIS)

    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 sprayed beryllium; beryllium research at the INEL; Japanese beryllium research activities for in-pile mockup tests on ITER; a study of beryllium bonding of copper alloy; new production technologies; thermophysical properties of a new ingot metallurgy beryllium product line; implications of beryllium:steam interactions in fusion reactors; and a test program for irradiation embrittlement of beryllium at JET

  13. Reactions during the processing of U3O8-Al cermet fuels

    International Nuclear Information System (INIS)

    The cermet fuel (U3O8 dispersed in Al) being considered thermodynamically unstable because of the potential for an exothermic metallothermic reduction reaction. This paper describes work performed to qualify the extent of reaction during powder metallurgy (P/M) processing of the U3O8-Al cermet fuel, and to determine the effect of partial reduction to U4O9 on the metallothermic reduction reaction. During the fabrication of the U3O8-Al cermet fuel by the P/M technique, a significant portion of the U3O8 is reduced to U4O9. The reaction between U4O9 and Al is also exothermic; however the maximum heat released by the reaction is substantially less than that released for the U3O8-Al reaction, approximately 335 J (80 cal) per gram of oxide reacted compared to 940 J (225 cal). Metallothermic reduction reactions for U3O8/U4O9/Al mixtures do not occur at the normal reactor operating temperature, ∼ 370 K (∼ 100 degrees C) or at temperatures below the melting point of aluminum, 930 K (660 degrees C)

  14. Analysis of the KANT experiment on beryllium using TRIPOLI-4 Monte Carlo code

    International Nuclear Information System (INIS)

    Beryllium is an important material in fusion technology for multiplying neutrons in blankets. However, beryllium nuclear data are differently presented in modern nuclear data evaluations. Recent investigations with the TRIPOLI-4 Monte Carlo simulation of the tritium breeding ratio (TBR) demonstrated that beryllium reaction data are the main source of the calculation uncertainties between ENDF/B-VII.0 and JEFF-3.1. To clarify the calculation uncertainties from data libraries on beryllium, in this study TRIPOLI-4 calculations of the Karlsruhe Neutron Transmission (KANT) experiment have been performed by using ENDF/B-VII.0 and new JEFF-3.1.1 data libraries. The KANT Experiment on beryllium has been used to validate neutron transport codes and nuclear data libraries. An elaborated KANT experiment benchmark has been compiled and published in the NEA/SINBAD database and it has been used as reference in the present work. The neutron multiplication in bulk beryllium assemblies was considered with a central D-T neutron source. Neutron leakage spectra through the 5, 10, and 17 cm thick spherical beryllium shells were calculated and five-group partial leakage multiplications were reported and discussed. In general, improved C/E ratios on neutron leakage multiplications have been obtained. Both ENDF/B-VII.0 and JEFF-3.1.1 beryllium data libraries of TRIPOLI-4 are acceptable now for fusion neutronics calculations.

  15. Quantitative differential thermal analysis study of the U3O8-Al thermite reaction

    International Nuclear Information System (INIS)

    Concerns about proliferation resistance of nuclear fuel cycles and fuels have prompted a reinvestigation of U3O8-Al cermet fuels currently being used in research and test reactors. In particular, higher loadings of U3O8 are being considered. These new fuel compositions are in the region of maximum possible thermal energy release from the high-temperature thermite reaction between the U3O8 and aluminum components. This study was initiated to quantitatively measure the amount of reaction heat evolved. A differential thermal analysis system was calibrated with materials of known heat of reaction. Subsequently, specimens of high-uranium-loaded U3O8-Al powder mixtures were analyzed. Thermite reaction heat measured for these specimens was much lower than expected. Specimens of simulated fuel plates showed similar low results. Possible reasons for this behavior are discussed

  16. Quantitative differential thermal analysis study of the U3O8-Al thermite reaction

    International Nuclear Information System (INIS)

    Concerns about proliferation resistance of nuclear fuel cycles and fuels have prompted a reinvestigation of U3O8-Al cermet fuels currently being used in research and test reactors. In particular, higher loadings of U3O8 are being considered. These new fuel compositions are in the region of maximum possible thermal energy release from the high-temperature thermite reaction between the U3O8 and aluminum components. This study was initiated to quantitatively measure the amount of reaction heat evolved. A differential thermal analysis system was calibrated with materials of known heat of reaction. Subsequently, specimens of high-uranium-loaded U3O8-Al powder mixtures were analyzed. Thermite reaction heat measured for these specimens was much lower than expected. Possible reason(s) for this behavior are discussed in the report

  17. Investigation of the $^{8}$Li($^{2}$H,p)$^{9}$Li Reaction at REX-ISOLDE

    CERN Multimedia

    2002-01-01

    We propose to investigate the $^{8}$Li($^{2}$H,p )$^{9}$Li reaction at REX-ISOLDE. The main aim is to test a recently found discrepancy in extracted spectroscopic factors for this reaction. As a byproduct we will obtain improved data relevant for predictions of the $^{8}$Li(n,$\\gamma$)$^{9}$Li rate in inhomogeneous nucleosynthesis. For the full experiment including beam tuning and background measurements we ask for 13 shifts.

  18. Angular distribution for 7Be(d,n)8B reaction at Ec.m. = 8.3 MeV and the astrophysical S17(0) factor for 7Be(p, γ)8B reaction

    International Nuclear Information System (INIS)

    The differential cross section for 7Be(d, n)8B reaction at Ec.m. 8.3 MeV has been measured by using a 7Be radioactive beam. The reaction cross section was determined to be 28 +- 3 mb. The astrophysical S17(0) factor for the 7Be(p, γ)8B reaction was derived to be 24 +- 5 eVb through the asymptotic normalization constant of 8B extracted from the experimental data. This results is found to be consistent with a previous value obtained from the same reaction at Ec.m. = 5.8 MeV, implying the energy independence of this indirect method within the uncertainty

  19. Processing Irradiated Beryllium For Disposal

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-11-01

    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.

  20. Isotopic Transmutations in Irradiated Beryllium and Their Implications on MARIA Reactor Operation

    International Nuclear Information System (INIS)

    Beryllium irradiated by neutrons with energies above 0.7 MeV undergoes (n,α) and (n,2n) reactions. The Be(n,α) reaction results in subsequent buildup of 6Li and 3He isotopes with large thermal neutron absorption cross sections causing poisoning of irradiated beryllium. The amount of the poison isotopes depends on the neutron flux level and spectrum. The high-flux MARIA reactor operated in Poland since 1975 consists of a beryllium matrix with fuel channels in cutouts of beryllium blocks. As the experimental determination of 6Li, 3H, and 3He content in the operational reactor is impossible, a systematic computational study of the effect of 3He and 6Li presence in beryllium blocks on MARIA reactor reactivity and power density distribution has been undertaken. The analysis of equations governing the transmutation has been done for neutron flux parameters typical for MARIA beryllium blocks. Study of the mutual influence of reactor operational parameters and the buildup of 6Li, 3H, and 3He in beryllium blocks has shown the necessity of a detailed spatial solution of transmutation equations in the reactor, taking into account the whole history of its operation. Therefore, fuel management calculations using the REBUS code with included chains for Be(n,α)-initiated reactions have been done for the whole reactor lifetime. The calculated poisoning of beryllium blocks has been verified against the critical experiment of 1993. Finally, the current 6Li, 3H, and 3He contents, averaged for each beryllium block, have been calculated. The reactivity drop caused by this poisoning is ∼7%

  1. Study of the nuclear reaction relevant to primordial nucleosynthesis: 8Li (α,n)11B

    International Nuclear Information System (INIS)

    A critical reaction in predicting abundances of 11B and heavier nuclides in the inhomogeneous models (IMs) is 8Li(α,n)11B, as 11B is the nuclide through which most heavier nuclides must pass, and that reaction apparently regulates the dominant pathway by which 11B is made in the IMs. The obvious complication in observing this reaction is the 840.3 ms half life of 8Li. A recent measurement of the inverse reaction 11B(n,α)8Li gives the ground state-ground state cross section for 8Li(α,n)11B. However, several 11B excited to be populated in 8Li(α,n)11B, so inference of the cross section of interest from measurement of the inverse reaction may underestimate the actual value by a large factor. Thus we have measured the cross section for 8Li(α,n)11B directly, using an 8Li radioactive beam and a novel detection technique. The results of that experiment are reported here. 23 refs., 4 figs

  2. Status of beryllium materials for fusion application

    International Nuclear Information System (INIS)

    The possible use of beryllium as a material for fusion reactors is discussed. Based on the results of recent Russian elaborations, which were not covered previously in the scientific literature, an attempt of complex analysis of the techniques of using beryllium is made. The specific requirements on beryllium as a protective material for first wall and divertor are considered. Also the possibility of creating a fusion grade of beryllium is discussed and an optimum strategy is suggested. (orig.)

  3. Spectrographic measurement of beryllium in the atmosphere

    International Nuclear Information System (INIS)

    We describe here a method for the spectrographic determination of beryllium on filters which is valid for amounts varying between 0,01 and 30 μg of beryllium and which is independent of the nature of the beryllium compound involved. This is a flux method (graphite-lithium carbonate mixture), the excitation being by a direct current arc. (author)

  4. Modes of Occurrence and Geological Origin of Beryllium in Coals from the Pu'an Coalfield, Guizhou, Southwest China

    Institute of Scientific and Technical Information of China (English)

    YANG Jianye

    2007-01-01

    The concentration, modes of occurrence and geological origin of beryllium in five workable coal beds from the Pu'an Coalfield of Guizbou were studied using the inductively coupled-plasma mass spectrometry (ICP-MS), floating and sinking experiments (FSE) and sequential chemical extraction procedures (SCEP). The results show that the average concentration of beryllium in coals from the Pu'an Coalfield is 1.54 μg/g, much lower than that in most Chinese and worldwide coals.Beryllium in the Pu'an coals was not significantly enriched. However, it should be noted that the No. 8 coal bed from the study area has a high concentration of beryllium, 6.89 μg/g, three times higher than the background value of beryllium in coal. Beryllium in coal mainly occurs as organic association and has predominantly originated from coal-forming plants when its concentration is relatively low. The concentration of beryllium occurring as organic association is close to that distributed in inorganic matter when beryllium concentration of coal is similar to its background value, and in addition to coal-forming plants, beryllium is mainly derived from detrital materials of terrigenous origin. When beryllium is anomalously enriched in coal, it mainly occurs as organic association and is derived from volcanic tonsteins leached for a long geological time and then adsorbed by organic matter in peat mire.

  5. Neutron irradiation behavior of ITER candidate beryllium grades

    Energy Technology Data Exchange (ETDEWEB)

    Kupriyanov, I.B.; Gorokhov, V.A.; Nikolaev, G.N. [A.A.Bochvar All-Russia Scientific Research Inst. of Inorganic Materials (VNIINM), Moscow (Russian Federation); Melder, R.R.; Ostrovsky, Z.E.

    1998-01-01

    Beryllium is one of the main candidate materials both for the neutron multiplier in a solid breeding blanket and for the plasma facing components. That is why its behaviour under the typical for fusion reactor loading, in particular, under the neutron irradiation is of a great importance. This paper presents mechanical properties, swelling and microstructure of six beryllium grades (DshG-200, TR-30, TshG-56, TRR, TE-30, TIP-30) fabricated by VNIINM, Russia and also one - (S-65) fabricated by Brush Wellman, USA. The average grain size of the beryllium grades varied from 8 to 25 {mu}m, beryllium oxide content was 0.8-3.2 wt. %, initial tensile strength was 250-680 MPa. All the samples were irradiated in active zone of SM-3 reactor up to the fast neutron fluence (5.5-6.2) {center_dot} 10{sup 21} cm{sup -2} (2.7-3.0 dpa, helium content up to 1150 appm), E > 0.1 MeV at two temperature ranges: T{sub 1} = 130-180degC and T{sub 2} = 650-700degC. After irradiation at 130-180degC no changes in samples dimensions were revealed. After irradiation at 650-700degC swelling of the materials was found to be in the range 0.1-2.1 %. Beryllium grades TR-30 and TRR, having the smallest grain size and highest beryllium oxide content, demonstrated minimal swelling, which was no more than 0.1 % at 650-700degC and fluence 5.5 {center_dot} 10{sup 21} cm{sup -2}. Tensile and compression test results and microstructure parameters measured before and after irradiation are also presented. (author)

  6. Experimental study to explore the $\\rm ^8Be$ induced nuclear reaction via the Trojan Horse Method

    CERN Document Server

    Qun-Gang, Wen; Shu-Hua, Zhou; Irgaziev, Bakhadir; Yuan-Yong, Fu; Spitaleri, Claudio; La Cognata, Marco; Jing, Zhou; Qiu-Ying, Meng; Lamia, Livio; Lattuada, Marcello

    2014-01-01

    To explore a possible indirect method for $\\rm ^8Be$ induced astrophysical reactions, the $\\rm ^9Be=({}^8Be+\\it n)$ cluster structure was studied via the Trojan Horse Method. It is the first time to study a super short life nucleus $\\rm ^8Be$ via the Trojan Horse Method, and it is the first time to make a valid test for $l=1$ Trojan-horse nucleus. The $\\rm ^9Be$ nucleus is assumed to have a ($\\rm {}^8Be+\\it n$) cluster structure and used as the Trojan-horse nucleus. The $\\rm ^8Be$ nucleus acts as a participant, while the neutron is a spectator to the virtual $\\rm ^8Be +{\\it d}\\rightarrow \\alpha + {}^6Li$ reaction via a suitable 3-body reaction $\\rm ^9Be +{\\it d}\\rightarrow \\alpha + {}^6Li +\\it n$. The experimental neutron momentum distribution inside $\\rm ^9Be$ was reconstructed. The agreement between experimental and theoretical momentum distribution indicates that there should be a ($\\rm {}^8Be+\\it n$) cluster structure inside $\\rm ^9Be$. Therefor the experimental study of $\\rm ^8Be$ induced reactions, for ...

  7. Cross section systematics of (d,p) reactions at 8.5 MeV

    International Nuclear Information System (INIS)

    Highlights: • We develop the empirical and semi-empirical formulae for (d,p) nuclear reaction cross sections. • We calculate the (d,p) nuclear reaction cross sections at 8.5 MeV projectile energy. • We researched of the pairing effects for the cross sections of the (d,p) nuclear reactions. • The obtained results have been compared with other cross section values. - Abstract: The empirical and semi-empirical systematics of the (d,p) nuclear reaction cross sections were obtained at the incident deuteron energies of 8.5 MeV. The experimental values for (d,p) reaction cross sections were collected from the literature and analyzed for the some target nuclei 27 < A < 121. The obtained cross section formulas by fitting two parameters for the (d,p) nuclear reactions were given. The obtained cross section results by using the systematics for (d,p) nuclear reactions have been discussed and compared with the ALICE–ASH code calculations and the available experimental data. Finally, the semi-empirical cross section formula gives a good fit with the experimental values for the (d,p) nuclear reaction

  8. Tritium release of Li4SiO4, Li2O and beryllium and chemical compatibility of beryllium with Li4SiO4, Li2O and steel (SIBELIUS irradiation)

    International Nuclear Information System (INIS)

    The objective of the SIBELIUS irradiation, a joint EC-US project performed at CEN Grenoble, was to investigate the oxidation kinetics of beryllium in contact with ceramic and the nature and extent of beryllium in contact with ceramic and the nature and extent of beryllium interaction with (316 L and 1.4914) steel in a neutron environment. In this work post irradiation examinations of SIBELIUS specimens performed at KfK are described. Tritium release of Li4SiO4, Li2O and beryllium was studied by out-of-pile annealing and chemical compatibility of beryllium with Li4SiO4, Li2O and steel by microscopic examinations. Tritium release of the ceramics was found to be consistent with SIBELIUS inpile observations and previous tests. Release of tritium generated in beryllium was found to be very slow, in accordance with previous work. For beryllium which was in contact with ceramic during irradiation, a second type of tritium, caused by injection of 2.7 MeV tritons generated in the ceramic, is observed. Release of injected tritium is faster than that of generated. Evidence for injected tritium in beryllium was also found in the microscopic studies. The observed minor chemical reactions of beryllium with steel and probably also those with breeder materials under neutron irradiation are consistent with the results of laboratory annealing tests. (orig.)

  9. Device for continuous control of beryllium content in atmosphere and on surfaces

    International Nuclear Information System (INIS)

    As known, beryllium and its compounds are characterized by high toxicity, therefore it is necessary to control constantly the content of beryllium and its compounds in the air and also on the surfaces of production areas and equipment to provide safety. The device for a quick measuring of beryllium content in the air, surface deposits and precipitations is described in the report. The mode of functioning of the device is based on nuclear reaction 9Be(αnγ)12C with the use of alpha-source based on plutonium-238, i.e. beryllium can be in any chemical state - metal, oxide, salt, etc. Gamma-quantums with energies 7,65 MeV (10%) and 4,43 MeV (90%), typical for beryllium, are generated as a result of interaction between alpha-particles and beryllium nuclei. The mentioned reaction with beryllium gives maximum release if comparing with another nuclides and along with high energy of gamma-quantums provides maximum sensibility of analysis without any disturbance from another elements. The number of generated gamma-quantums is in proportion to beryllium content in a probe. The device consists of the probe-preparation unit, control unit and two-way communication line. The unit of probe extraction can be placed in different points of an area, at a large distance - up to 30 meters. This device is compact and easy to transport by one person. The device control can be realized by operator via the remote control unit or automatically by the given program. The time of the probe data processing is 10-15 min. The use of the device allows to carry out beryllium content measuring in the mode of current time. (author)

  10. Experimental study to explore the $\\rm ^8Be$ induced nuclear reaction via the Trojan Horse Method

    OpenAIRE

    Qun-Gang, Wen; Cheng-Bo, Li; Shu-Hua, Zhou; Irgaziev, Bakhadir; Yuan-Yong, Fu; Spitaleri, Claudio; La Cognata, Marco; Jing, Zhou; Qiu-Ying, Meng; Lamia, Livio; Lattuada, Marcello

    2014-01-01

    To explore a possible indirect method for $\\rm ^8Be$ induced astrophysical reactions, the $\\rm ^9Be=({}^8Be+\\it n)$ cluster structure was studied via the Trojan Horse Method. It is the first time to study a super short life nucleus $\\rm ^8Be$ via the Trojan Horse Method, and it is the first time to make a valid test for $l=1$ Trojan-horse nucleus. The $\\rm ^9Be$ nucleus is assumed to have a ($\\rm {}^8Be+\\it n$) cluster structure and used as the Trojan-horse nucleus. The $\\rm ^8Be$ nucleus act...

  11. Total reaction cross sections for 8Li + 90Zr at near-barrier energies

    International Nuclear Information System (INIS)

    Total reaction cross sections for the radioactive nucleus 8Li on 90Zr are reported at the near-barrier energies of 18.5 and 21.5MeV, derived from quasi-elastic scattering measurements. An analysis of the quasi-elastic scattering results is performed within an optical model framework using the BDM3Y1 interaction and total reaction cross sections are deduced. These quantities, appropriately reduced, are compared with previous data obtained in elastic scattering measurements with well and weakly bound projectiles on various targets and a formula for predicting total reaction cross sections with an uncertainty of ∝ 20 % is obtained. Further on, the ratios of direct to total reaction cross sections are estimated for 6,8Li on various targets and are compared with CDCC or CRC calculations. The energy dependence of the optical potential is also discussed. (orig.)

  12. Elastic scattering and total reaction cross sections for 8Li+12C

    International Nuclear Information System (INIS)

    Full text: The elastic scattering angular distribution for 8Li on 12C has been measured at ELAB= 23.9 MeV with 8Li radioactive nuclear beam produced by the Radioactive Ion Beams in Brazil facility (RIBRAS). This angular distribution was analysed in terms of optical model with Woods-Saxon and double-folding Sao Paulo potentials. The roles of the breakup and inelastic channels were also investigated with cluster folding and deformed potentials, respectively, through coupled channels calculations. The angular distributions for the proton-transfer 12C(8Li,9Be)11B reaction was also measured at the same energy, simultaneously with the elastic scattering. The spectroscopic factor for the 9Be I 8Li+p> bound system was obtained through DWBA (Distorted-Wave Born Approximation) calculations with the code Fresco, and compared with shell model calculations and other experimental values. The spectroscopic factor obtained was used for normalization of the capture reaction cross section 8Li(p, gamma)9Begs. The depth of the scattered potential obtained was 40,1 +- 1,6 MeV. The astrophysical S-factor curves and the reaction rate for the capture reaction 8Li(p,gamma)9Begs were calculated. Total reaction cross sections for the present system were also extracted from the elastic scattering analysis. A systematic of the reduced reaction cross section obtained from the present and published data on 6;7;8Li isotopes on 12C was performed as a function of energy. (author)

  13. An efficient synthesis of 8-substituted Odoratine derivatives by the Suzuki coupling reaction

    Indian Academy of Sciences (India)

    Ravi Kumar P; Balakrishna C; Murali B; Ramakrishna Gudipati; Prasanta K Hota; Avinash B Chaudhary; Jaya Shree A; Satyanarayana Yennam; Manoranjan Behera

    2016-03-01

    An efficient method for the preparation of 8-substituted odoratine [(3-(3', 4' -methylenedioxyphenyl)-5,6,7-trimethoxyisoflavone] derivatives, structurally similar to glaziovianin A, a known cytotoxic substance, has been described. The key steps in the synthesis are site selective bromination reaction followed by Suzuki coupling reaction in very good yield. The structural assignment of the bromo derivative was determined utilizing 2D-HMBC and NOEs NMR techniques.

  14. Worker Environment Beryllium Characterization Study

    International Nuclear Information System (INIS)

    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.'

  15. Worker Environment Beryllium Characterization Study

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environment, Safety, Health & Quality

    2009-12-28

    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.”

  16. The kinetics and mechanism of the reaction of uranium(VI) with 8-quinolinol and 8-hydroxy-5-quinolinesulfonic acid

    International Nuclear Information System (INIS)

    The kinetics of the reaction of uranium(VI) with 8-quinolinol and 8-hydroxy-5-quinolinesulfonate under the conditions of 1:1 chelate formation in the pH range 3.6-4.6 at different temperatures (20-30degC) and ionic strength I = 0.1 moldm-3 (KNO3) have been studied. A dual path mechanism involving both UO2(aq)2+ and UO2(OH)(aq)+ and the partially deprotonated ligand (LH, LH-) is consistent under the experimental conditions. The different rate constants under the condition of equilibrium have been determined. The results conform to kobs/B = k1[H+] + k2Kh; where B = (1/Q) + Ka(1)TU / ([H+] + Ka(1)) (Kh + [H+]); Kh = hydrolysis constant of UO2(aq)2+; Ka(1) = first deprotonation constant of the ligand, LH2 (charges are omitted); k1 and k2 are the second order forward rate constants of UO2(aq)2+ and UO2(OH)(aq)+ respectively and Q is the equilibrium constant of the reaction, UO22+ + LH ↔ UO2L+ + H+, where LH represents the partially deprotonated form of the ligand, 8-quinolinol and a similar reaction occurs for deprotonated 8-hydroxy-5-quinolinesulfonate (LH-). Thermodynamic parameters for each of the steps have been determined. The results have been compared with those of recent findings in the interaction of cerium(VI) and iron(III) with these ligands. UO2(aq)2+ has been argued to react through a dissociative interchange (Id) mechanism and its characteristic water exchange rate has been found as a rough estimate. Similarly for UO2(OH)(aq)+, a dissociative mechanism has been speculated. (author)

  17. 7Be- and 8B-reaction dynamics at Coulomb barrier energies

    Science.gov (United States)

    Mazzocco, M.; Boiano, A.; Boiano, C.; La Commara, M.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Signorini, C.; Strano, E.; Torresi, D.; Yamaguchi, H.; Kahl, D.; Acosta, L.; Di Meo, P.; Fernandez-Garcia, J. P.; Glodariu, T.; Grebosz, J.; Guglielmetti, A.; Imai, N.; Hirayama, Y.; Ishiyama, H.; Iwasa, N.; Jeong, S. C.; Jia, H. M.; Keeley, N.; Kim, Y. H.; Kimura, S.; Kubono, S.; Lay, J. A.; Lin, C. J.; Marquinez-Duran, G.; Martel, I.; Miyatake, H.; Mukai, M.; Nakao, T.; Nicoletto, M.; Pakou, A.; Rusek, K.; Sakaguchi, Y.; Sánchez-Benítez, A. M.; Sava, T.; Sgouros, O.; Stefanini, C.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Stroe, L.; Teranishi, T.; Toniolo, N.; Wakabayashi, Y.; Watanabe, Y. X.; Yang, L.; Yang, Y. Y.

    2016-05-01

    We investigated the reaction dynamics induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at energies around the Coulomb barrier. The two measurements are strongly interconnected, being 7Be (Sα = 1.586 MeV) the loosely bound core of the even more exotic 8B (Sp = 0.1375 MeV) nucleus. Here we summarize the present status of the data analysis for the measurement of the elastic scattering process for both reactions and the preliminary results for the optical model analysis of the collected data.

  18. 7Be- and 8B-reaction dynamics at Coulomb barrier energies

    Directory of Open Access Journals (Sweden)

    Mazzocco M.

    2016-01-01

    Full Text Available We investigated the reaction dynamics induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at energies around the Coulomb barrier. The two measurements are strongly interconnected, being 7Be (Sα = 1.586 MeV the loosely bound core of the even more exotic 8B (Sp = 0.1375 MeV nucleus. Here we summarize the present status of the data analysis for the measurement of the elastic scattering process for both reactions and the preliminary results for the optical model analysis of the collected data.

  19. Fusion and direct reactions around the Coulomb barrier with the neutron-rich 8He

    International Nuclear Information System (INIS)

    Radioactive ion beams like 8He, open new possibilities to investigate the influence of new and exotic structures on reaction mechanisms. This thesis presents the first investigations of reactions of the weakly bound, Borromean nucleus, 8He, at energies around the Coulomb barrier. The low intensity of radioactive ion beams (∼ 105 pps) necessitated the development of a new sensitive and selective technique for the precise and accurate measurement of fusion cross sections. In the 8He+197Au system, excitation functions for fusion and neutron(s) transfer were measured. In the 8He+65Cu system, differential and integral cross sections for various processes like elastic scattering, neutron transfer and fusion were measured using both, inclusive and exclusive measurements of characteristic γ-rays, charged particles and neutrons. These experimental results combined with coupled reaction channels calculations demonstrated the inter-connectivity among the various reaction processes. The internal structure of 8He influenced the tunneling process and neutron(s) transfer and interestingly, revealed an unexpected behavior within the Helium isotopic chain. Further, a systematic analysis of the known fusion excitation functions showed that the increase in sub-barrier fusion cross sections associated with the internal structure of nuclei, is in fact much larger for 'normal' nuclei than for light, weakly-bound 'exotic' nuclei. (author)

  20. Reactions of the OOH radical with guanine: Mechanisms of formation of 8-oxoguanine and other products

    Science.gov (United States)

    Kumar, Nagendra; Shukla, P. K.; Mishra, P. C.

    2010-09-01

    The mutagenic product 8-oxoguanine (8-oxoGua) is formed due to intermediacy of peroxyl (OOR) radicals in lipid peroxidation and protein oxidation-induced DNA damage. The mechanisms of these reactions are not yet understood properly. Therefore, in the present study, the mechanisms of formation of 8-oxoGua and other related products due to the reaction of the guanine base of DNA with the hydroperoxyl radical (OOH) were investigated theoretically employing the B3LYP and BHandHLYP hybrid functionals of density functional theory and the polarizable continuum model for solvation. It is found that the reaction of the OOH radical with guanine can occur following seven different mechanisms leading to the formation of various products including 8-oxoGua, its radicals, 5-hydroxy-8-oxoguanine and CO 2. The mechanism that yields 8-oxoGua as an intermediate and 5-hydroxy-8-oxoGua as the final product was found to be energetically most favorable.

  1. Development of radiation resistant grades of beryllium for nuclear and fusion facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kupriyanov, I.B.; Gorokhov, V.A.; Nikolaev, G.N. [Russia Research Institute of Inorganic Materials, Moscow (Russian Federation)

    1995-09-01

    R&D results on beryllium with high radiation resistance obtained recently are described in this report. The data are presented on nine different grades of isotropic beryllium manufactured by VNIINM and distinguished by both initial powder characteristics and properties of billets, made of these powders. The average grain size of the investigated beryllium grades varied from 8 to 26 {mu}m, the content of beryllium oxide was 0.9 - 3.9 wt.%, the dispersity of beryllium oxide - 0.04 - 0.5 {mu}m, tensile strength -- 250 - 650 MPa. All materials were irradiated in SM - 2 reactor over the temperature range 550 - 780{degrees}C. The results of the investigation showed, that HIP beryllium grades are less susceptible to swelling at higher temperatures in comparison with hot pressed and extruded grades. Beryllium samples, having the smallest grain size, demonstrated minimal swelling, which was less than 0.8 % at 750{degrees}C and Fs = 3.7 {center_dot}10{sup 21} cm{sup -2} (E>0.1 MeV). The mechanical properties, creep and microstructure parameters, measured before and after irradiation, are presented.

  2. Investigation of 7Li(n, γ)8Li reaction by law energy

    International Nuclear Information System (INIS)

    The wave functions and main spectroscopic characteristics of the 8Li nucleus as well as the interaction potential in the 7Li+n channel are calculated within the frames of the three-body αtn-potential cluster model. The complete cross sections and reaction velocities of the 7Li(n, γ)8Li are determined along with the above values in the area of the energy up to 1 MeV

  3. OVERVIEW OF BERYLLIUM SAMPLING AND ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Brisson, M

    2009-04-01

    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.

  4. Beryllium - A Unique Material in Nuclear Applications

    International Nuclear Information System (INIS)

    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

  5. Analysis of impurities in beryllium, affecting evaluation of the tritium breeding ratio

    International Nuclear Information System (INIS)

    In most conceptual fusion power reactor designs, it is proposed to use beryllium as a neutron multiplier in the blanket. Detailed chemical composition of beryllium is necessary for evaluation of the tritium breeding ratio, and estimating the activation and transmutation of beryllium in the fusion reactor. In the present report, special attention was paid to a detailed analysis of impurities in beryllium, relevant to the tritium breeding ratio evaluation. Two different methods were used for the study of impurities: an analysis of the local sample by the ICP-MS method, and an integral analysis of the beryllium assembly, using the pulsed neutron method. The latter method was proposed as the most effective way of analyzing the integral effect to impurities in beryllium on production of the tritium on the lithium-6. The evaluation of the integral effect was based on time behaviour observations of the thermal neutron flux, following the injection of a burst of D-T neutrons into the beryllium assembly. Structural beryllium grade (S-200-F, Brush Wellman Inc.) was used in the study. The influence of the impurities has resulted in a smaller experimental reaction rate for production of the tritium on lithium-6, due to an increase in the parasitic neutron absorption. Experimental data was compared with the reference data and the MCNP Monte Carlo calculations using the JENDL-3.2 data set. Results indicate, that the measured absorption cross section of thermal neutrons in beryllium blocks is approximately 30% larger than the calculated value, based on the data, specified by the manufacturing company. ICP-MS analysis indicated that the impurities include elements such as Li, B, Cd and others. These elements affect the absorption cross section even if the content of impurities is less than 10 ppm. (author)

  6. Study of the reaction pp → pp π+ π- at 8 GeV/c

    International Nuclear Information System (INIS)

    We present here a study of the reaction pp → pp π+ π- from an experience performed into the CERN 2 m HBC with an incident proton beam of 8 GeV/c. We describe the most remarkable features of this reaction and give an analysis of its global mechanism. Moreover, we estimate the cross sections of the various produced resonances. We compare our experimental data to the Deck and Berger models in which we introduce some improvements. Furthermore, we study the reaction pp → Δ++Δ0 in terms of peripheral models, with or without absorption and also with the exchange of a Regge trajectory. The comparison of theoretical and experimental results is satisfactory and allows to understand the mechanism of the whole reaction. (author)

  7. Investigation of the mechanism of interaction of Lithium 6 ions on Beryllium 9

    International Nuclear Information System (INIS)

    The objective of this research on the interaction of Lithium 6 and Beryllium 9 ions is to obtain new indications on the mode of interaction of these heavy ions, and on the configuration of target nuclei and projectile nuclei. In a first part, the author presents and describes the experimental conditions which comprise a Van de Graaff accelerator, a source, a stripper, and a target. He reports the study of α particles emitted by the reaction between the Lithium and Beryllium ions: description of the experimental installation (irradiation chamber and method), presentation and interpretation of experimental results. In the next part, he reports the study of Lithium 7 and Beryllium 10 nuclides emitted by disintegration of Beryllium 11: description of experimental conditions, variations of cross sections, variation of the cross section rate, and interpretation. The author then addresses the study of the intervention of the mode of interaction by 15N compound nucleus in the reactions between lithium and beryllium ions: study of intensities of the different spectrum lines, measurement of the Doppler effect produced of the 479 keV line, interpretation of results. In conclusion, the author analyses the mechanism of interaction between lithium and beryllium ions, and discusses different theories: the Newns and Glendenning theories, and the Leigh theory

  8. Study of the U3O8-Al thermite reaction and strength of reactor fuel tubes

    International Nuclear Information System (INIS)

    Heating tests using 53 wt % U3O8-Al pellets show that an exothermic reaction occurs between 875 and 10000C and takes 10 to 20 seconds to reach maximum temperature. The maximum temperature is a function of particle size of the U3O8 with large particles exhibiting lower peak temperatures. The calculated energy release was 123 cal/g of U3O8-aluminum fuel. Tests using aluminum clad outer fuel tube sections gave lower peak temperatures than for pellets. No violent reactions occurred. The results are reasonably consistent with recent reported data indicating that the exothermic U3O8-Al reaction is not an important energy source. The compressive and tensile strengths of U3O8 tubes above 6600C are low. In compression, sections with 2 psi average axial stress failed at 9170C, while sections with 7 psi failed at 6690C. Tubes with U-Al alloy cores failed at about 6700C with no applied load. The stresses in fuel tubes during a reactor transient may range up to several hundred psi and are less than 7 psi only in the upper part of the fuel tube

  9. Reaction mechanisms in collisions induced by 8B beam close to the barrier

    CERN Multimedia

    The aim of the proposed experiment is to investigate on the reaction dynamics of proton-halo induced collisions at energies around the Coulomb barrier where coupling to continuum effects are expected to be important. We propose to measure $^{8}$B+$^{64}$Zn elastic scattering angular distribution together with the measurement, for the first time, of p-$^{7}$Be coincidences coming from transfer and/or break-up of $^{8}$B. The latter will allow a better understanding of the relative contribution of elastic $\\textit{vs}$ non-elastic break-up in reactions induced by extremely weakly-bound nuclei. We believe that with the availability of the post accelerated $^{8}$B beam at REX-ISOLDE we will be able to collect for the first time high quality data for the study of such an important topic.

  10. Compatibility problems with beryllium in ceramic blankets

    International Nuclear Information System (INIS)

    Compatibility of beryllium with structural materials (316L austenitic steel and 1.4914 martensitic steel) and with tritium breeding ceramics (lithium aluminate or silicate) has been studied in contact tests between 550 C and 700 C and for durations reaching 3000 hours. Beryllium-ceramic interaction is negligeable in all the temperature range with aluminate and up to 600 C with silicates. On the other hand, noticeable interaction is observed between beryllium and 316L steel at 580 C and above. Beryllium interaction with 1.4914 steel is visible only at 650 C and above and its amplitude is lower than 316L steel one. In these two cases, the superficial layer is brittle, and adherent to the steel. Comparison between beryllium - 0.4 wt% calcium alloy and beryllium at 700 C shows that interaction with steels or ceramics is qualitatively the same but slightly weaker. (author). 6 refs.; 6 figs.; 3 tabs

  11. Belgian research on fusion beryllium waste

    International Nuclear Information System (INIS)

    Future fusion power plants will generate important quantities of neutron irradiated beryllium. Although recycling is the preferred management option for this waste, this may not be technically feasible for all of the beryllium, because of its radiological characteristics. Therefore, at SCK·CEN, we initiated a research programme aimed at studying aspects of the disposal of fusion beryllium, including waste characterisation, waste acceptance criteria, conditioning methods, and performance assessment. One of the main issues to be resolved is the development of fusion-specific waste acceptance criteria for surface or deep geological disposal, in particular with regard to the tritium content. In case disposal is the only solution, critical nuclides can be immobilised by conditioning the waste. As a first approach to immobilising beryllium waste, we investigated the vitrification of beryllium. Corrosion tests were performed on both metallic and vitrified beryllium to provide source data for performance assessment. Finally, a first step in performance assessment was undertaken. (author)

  12. Advances in Identifying Beryllium Sensitization and Disease

    Directory of Open Access Journals (Sweden)

    Peter Kowalski

    2010-01-01

    Full Text Available Beryllium is a lightweight metal with unique qualities related to stiffness, corrosion resistance, and conductivity. While there are many useful applications, researchers in the 1930s and l940s linked beryllium exposure to a progressive occupational lung disease. Acute beryllium disease is a pulmonary irritant response to high exposure levels, whereas chronic beryllium disease (CBD typically results from a hypersensitivity response to lower exposure levels. A blood test, the beryllium lymphocyte proliferation test (BeLPT, was an important advance in identifying individuals who are sensitized to beryllium (BeS and thus at risk for developing CBD. While there is no true "gold standard" for BeS, basic epidemiologic concepts have been used to advance our understanding of the different screening algorithms.

  13. Thermodynamic properties of beryllium hydroxide

    International Nuclear Information System (INIS)

    The study of the hydro-thermal decomposition of beryllium hydroxide has made it possible to determine the free energy of formation and the entropy. The results obtained are in good agreement with the theoretical values calculated from the solubility product of this substance. They give furthermore the possibility of acquiring a better understanding of the BeO-H2O-Be (OH)2 system between 20 and 1500 C. (authors)

  14. Current Treatment of Chronic Beryllium Disease

    OpenAIRE

    Sood, Akshay

    2009-01-01

    The current mainstay of management of chronic beryllium disease involves cessation of beryllium exposure and use of systemic corticosteroids. However, there are no randomized controlled trials to assess the effect of these interventions on the natural history of this disease. Despite this limitation, it is prudent to remove patients with chronic beryllium disease from further exposure and consider treating progressive disease early with long-term corticosteroids. The effect of treatment shoul...

  15. MEASUREMENTS OF THE PROPERTIES OF BERYLLIUM FOIL

    International Nuclear Information System (INIS)

    The electrical conductivity of beryllium at radio frequency (800 MHz) and liquid nitrogen temperature were investigated and measured. This summary addresses a collection of beryllium properties in the literature, an analysis of the anomalous skin effect, the test model, the experimental setup and improvements, MAFIA simulations, the measurement results and data analyses. The final results show that the conductivity of beryllium is not as good as indicated by the handbook, yet very close to copper at liquid nitrogen temperature

  16. New audio applications of beryllium metal

    International Nuclear Information System (INIS)

    The major applications of beryllium metal in the field of audio appliances are for the vibrating cones for the two types of speakers 'TWITTER' for high range sound and 'SQUAWKER' for mid range sound, and also for beryllium cantilever tube assembled in stereo cartridge. These new applications are based on the characteristic property of beryllium having high ratio of modulus of elasticity to specific gravity. The production of these audio parts is described, and the audio response is shown. (author)

  17. Thermally-induced expansion in the 8 GeV/c $\\pi^{-} + ^{197}Au$ reaction

    CERN Document Server

    Lefort, T; Botvina, A S; Durand, D; Kwiatkowski, K K; Hsi, W C; Pienkowski, L; Back, B B; Breuer, H; Gushue, S; Korteling, R G; Martin, R L E; Ramakrishnan, E; Remsberg, L P; Rowland, D; Ruangma, A; Viola, V E; Winchester, E M; Yennello, S J

    2000-01-01

    Fragment kinetic energy spectra for reactions induced by 8.0 GeV/c order to deduce the possible existence and influence of thermal expansion. The average fragment kinetic energies are observed to increase systematically with fragment charge and to be nearly independent of excitation energy. Comparison of the data with statistical multifragmentation models indicates the onset of extra collective thermal expansion near an excitation energy of E*/A expansion observed in heavy-ion-induced reactions, consistent with the interpretation that the latter expansion may be driven primarily by dynamical effects such as compression/decompression.

  18. The beryllium "double standard" standard.

    Science.gov (United States)

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

    2003-01-01

    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

  19. Recommended design correlations for S-65 beryllium

    International Nuclear Information System (INIS)

    The properties of tritium and helium behavior in irradiated beryllium are reviewed, along with the thermal-mechanical properties needed for ITER design analysis. Correlations are developed to describe the performance of beryllium in a fusion reactor environment. While this paper focuses on the use of beryllium as a plasma-facing component (PFC) material, the correlations presented here can also be used to describe the performance of beryllium as a neutron multiplier for a tritium breeding blanket. The performance properties for beryllium are subdivided into two categories: properties which do not change with irradiation damage to the bulk of the material; and properties which are degraded by neutron irradiation. The approach taken in developing properties correlations is to describe the behavior of dense, pressed S-65 beryllium as a function of temperature. As there are essentially no data on the performance of porous and/or irradiated S-65 beryllium, the degradation of properties with as-fabricated porosity and irradiation are determined form the broad data base on S-200F, as well as other types and grades, and applied to S-65 beryllium by scaling factors. The resulting correlations can be used for Be produced by vacuum hot pressing (VHP) and cold-pressing (CP)/sintering(S)/hot-isostatic-pressing(HIP). The performance of plasma-sprayed beryllium is discussed but not quantified

  20. (Beryllium). Internal Report No. 137, Jan. 15, 1958

    International Nuclear Information System (INIS)

    After a brief summary of the physical and chemical properties of beryllium, the various chemical treatments which can be applied to beryllium minerals either directly or after a physical enrichment are discussed. These various treatments give either the hydroxide or beryllium salts, from which either beryllium oxide or metallic beryllium can easily be obtained. The purification, analysis and uses of beryllium are also briefly discussed. (author)

  1. Study of the U3O8-Al thermite reaction and strength of reactor fuel tubes

    International Nuclear Information System (INIS)

    Research and test reactors are presently operated with aluminum-clad fuel elements containing highly enriched uranium-aluminum alloy cores. To lower the enrichment and still maintain reactivity, the uranium content of the fuel element will need to be higher than currently achievable with alloy fuels. This will necessitate conversion to other forms such as U3O8-aluminum cermets. Above the aluminum melting point, U3O8 and aluminum undergo an exothermic thermite reaction and cermet fuel cores tend to keep their original shape. Both factors could affect the course and consequences of a reactor accident, and prompted an investigation of the behavior of cermet fuels at elevated temperatures. Tests were carried out using pellets and extruded tube-sections with 53 wt % U3O8 in aluminum. This content corresponds to a theoretical uranium density of 1.9 g/cc. Results indicate that the thermite reaction occurs at about 9000C in air without a violent effect. The heat of reaction was approximately 123 cal/g of U3O8-aluminum fuel. Tensile and compressive strength of the fuel tube section is low above 6600C. In tension, sections failed at about the aluminum melting point. In compression with 2-psi average axial stress, failure occurred at 9170C, while 7 psi average axial stress produced failure at 6690C

  2. Electron microscope study of irradiated beryllium oxide

    International Nuclear Information System (INIS)

    The beryllium oxide is studied first by fractography, before and after irradiation, using sintered samples. The fractures are examined under different aspects. The higher density sintered samples, with transgranular fractures are the most interesting for a microscopic study. It is possible to mark the difference between the 'pores' left by the sintering process and the 'bubbles' of gases that can be produced by former thermal treatments. After irradiation, the grain boundaries are very much weakened. By annealing, it is possible to observe the evolution of the gases produced by the reaction (n, 2n) and (n. α) and gathered on the grain boundaries. The irradiated beryllium oxide is afterwards studied by transmission. For that, a simple method has been used: little chips of the crushed material are examined. Clusters of point defects produced by neutrons are thus detected in crystals irradiated at the three following doses: 6 x 1019, 9 x 1019 and 2 x 1020 nf cm-2 at a temperature below 100 deg. C. For the irradiation at 6 x 1019 nf cm-2, the defects are merely visible, but at 2 x l020 nf cm-2 the crystals an crowded with clusters and the Kikuchi lines have disappeared from the micro-diffraction diagrams. The evolution of the clusters into dislocation loops is studied by a series of annealings. The activation energy (0,37 eV) calculated from the annealing curves suggests that it must be interstitials that condense into dislocation loops. Samples irradiated at high temperatures (650, 900 and 1100 deg. C) are also studied. In those specimens the size of the loops is not the same as the equilibrium size obtained after out of pile annealing at the same temperature. Those former loops are more specifically studied and their Burgers vector is determined by micro-diffraction. (author)

  3. Geochemistry of beryllium in Bulgarian coals

    Energy Technology Data Exchange (ETDEWEB)

    Eskenazy, Greta M. [Geology Department, University of Sofia ' St. Kl. Ohridski' , Tzar Osvoboditel 15, Sofia 1504 (Bulgaria)

    2006-04-03

    The beryllium content of about 3000 samples (coal, coaly shales, partings, coal lithotypes, and isolated coalified woods) from 16 Bulgarian coal deposits was determined by atomic emission spectrography. Mean Be concentrations in coal show great variability: from 0.9 to 35 ppm for the deposits studied. There was no clear-cut relationship between Be content and rank. The following mean and confidence interval Be values were measured: lignites, 2.6+/-0.8 ppm; sub-bituminous coals, 8.2+/-3.3 ppm; bituminous coals, 3.0+/-1.2 ppm; and anthracites, 19+/-9.0 ppm. The Be contents in coal and coaly shales for all deposits correlated positively suggesting a common source of the element. Many samples of the coal lithotypes vitrain and xylain proved to be richer in Be than the hosting whole coal samples as compared on ash basis. Up to tenfold increase in Be levels was routinely recorded in fusain. The ash of all isolated coalified woods was found to contain 1.1 to 50 times higher Be content relative to its global median value for coal inclusions. Indirect evidence shows that Be occurs in both organic and inorganic forms. Beryllium is predominantly organically bound in deposits with enhanced Be content, whereas the inorganic form prevails in deposits whose Be concentration approximates Clarke values. The enrichment in Be exceeding the coal Clarke value 2.4 to 14.5 times in some of the Bulgarian deposits is attributed to subsynchronous at the time of coal deposition hydrothermal and volcanic activity. (author)

  4. Betti reaction enables efficient synthesis of 8-hydroxyquinoline inhibitors of 2-oxoglutarate oxygenases.

    Science.gov (United States)

    Thinnes, C C; Tumber, A; Yapp, C; Scozzafava, G; Yeh, T; Chan, M C; Tran, T A; Hsu, K; Tarhonskaya, H; Walport, L J; Wilkins, S E; Martinez, E D; Müller, S; Pugh, C W; Ratcliffe, P J; Brennan, P E; Kawamura, A; Schofield, C J

    2015-10-28

    There is interest in developing potent, selective, and cell-permeable inhibitors of human ferrous iron and 2-oxoglutarate (2OG) oxygenases for use in functional and target validation studies. The 3-component Betti reaction enables efficient one-step C-7 functionalisation of modified 8-hydroxyquinolines (8HQs) to produce cell-active inhibitors of KDM4 histone demethylases and other 2OG oxygenases; the work exemplifies how a template-based metallo-enzyme inhibitor approach can be used to give biologically active compounds. PMID:26345662

  5. Methods for the mitigation of the chemical reactivity of beryllium in steam

    International Nuclear Information System (INIS)

    In the safety assessment of future fusion reactors, the reaction of beryllium with steam remains one of the main concerns. In this case of a loss of coolant accident (LOCA), the use of beryllium in combination with pressurized water as coolant can lead to excessive hydrogen production due to the reaction Be + H2O = BeO +H2 +heat. Because of the explosion hazard associated with this phenomenon, the hydrogen generation rate during a LOCA should be reduced as much as possible. Therefore, we started an R and D programme aimed at investigating mitigation methods for the beryllium/steam reaction. Beryllium samples were implanted in a 210 kV ion implanter at ITN (Institute Technologico e Nuclear) Lisbon, with calcium and aluminum ions respectively in a 210 kV ion implanter at ITN Lisbon. The average implantation depth was estimated at 100 nm for both elements. The chemical activity of these samples in steam was then measured at SCK-CEN (The Belgian Nuclear Research Center) in a dedicated experimental facility providing coupled thermogravimetry/mass spectrometry. The observed oxidation kinetics was parabolic. In comparison to reference un-doped material, the reactivity of doped beryllium after 30 minutes of exposure decreased with a factor 2 to 4. The mitigating effect was higher for calcium-doped than for aluminum-doped samples. As a second approach, beryllium pebbles were pre-oxidized in dry air at 400 degree C during ten hours. This did not result in an appreciable decrease in chemical activity. The results indicate that doping may be a viable means of mitigating the chemical activity of beryllium in steam. (author)

  6. Production of a covalent flavin linkage in lipoamide dehydrogenase. Reaction with 8-Cl-FAD.

    Science.gov (United States)

    Moore, E G; Cardemil, E; Massey, V

    1978-09-25

    A method is described for preparation of apolipoamide dehydrogenase which gives quantitative removal of FAD. Active holoenzyme can be reconstituted by incubation with FAD. Reconstitution of apoenzyme with 8-Cl-FAD results in the fixation of most of the flavin to the protein in a covalently bound form. The portion noncovalently bound was shown to be unmodified 8-Cl-FAD. The covalently bound flavin has an absorption spectrum quite different from that of 8-Cl-FAD. It has a single band in the visible with a maximum at 459 nm (extinction coefficient of 22 mM-1 cm-1) and a shoulder at 480 nm. Model reactions between 8-Cl-Flavin (riboflavin or FAD) and organic thiols (thiophenol, beta-mercaptoethanol, or N-acetylcysteine) give products with spectra which are similar to that of FAD covalently bound to lipoamide dehydrogenase. The products of the model reactions have a single visible band with a maximum at 480 nm (extinction coefficient of 23.6 mM-1 cm-1 to 28.4 mM-1 cm-1) and a shoulder at 460 nm. The products of the model reaction and the covalently bound FAD of lipoamide dehydrogenase appear to be the result of a nucleophilic attack on the carbon at position 8 of the flavin ring by a thiolate anion, displacing the chloride. Thus, the product of the model reaction is 8-(RS)-flavin, and the product of the reaction between 8-Cl-FAD and protein probably has a cysteinyl residue covalently attacked at position 8 of FAD. Reconstitution of apoliopoamide dehydrogenase with 8-Cl-FAD gives two enzyme products which are fractionated by ammonium sulfate. Enzyme fractionating between 20% and 45% ammonium sulfate is monomeric and contains covanently bound FAD. Enzyme fractionating between 55% and 75% ammonium sulfate is dimeric and contains both covalently bound FAD and noncovalently bound 8-Cl-FAD. Both protein fractions contain one FAD per protein subunit and both are active with physiological substrates with Km values for NAD and dihydrolipoamide similar to those of native lipoamide

  7. ICT diagnostic method of beryllium welding quality

    International Nuclear Information System (INIS)

    To avoid the interference of high density material for the quality assay of beryllium welding line, a slice by slice scanning method was proposed based upon the research results of the Industrial Computerized Tomography (ICT) diagnostics for weld penetration, weld width, off-centered deviation and weld defects of beryllium-ring welding seam with high density material inside

  8. Some aspects of beryllium disposal in Kazakhstan

    International Nuclear Information System (INIS)

    Historically in Kazakhstan all disposals of used beryllium and beryllium wasted materials were stored and recycled at JSC ''Ulba Metallurgical Plant''. Since Ulba Metallurgical Plant (beside beryllium and tantalum production) is one of the world largest complex producers of fuel for nuclear power plants as well it has possibilities, technologies and experience in processing toxic and radioactive wastes related with those productions. At present time only one operating Kazakhstan research reactors (EWG1M in Kurchatov) contains beryllium made core. The results of current examination of that core allow using it without replacement long time yet (at least for next five-ten years). Nevertheless the problem how to utilize such irradiated beryllium becomes actual issue for Kazakhstan even today. Since Kazakhstan is the member of ITER/DEMO Reactors Projects and is permanently considered as possible provider of huge amount of beryllium for those reactors so that is the reason for starting studies of possibilities of large scale processing/recycling of such disposed irradiated beryllium. It is clear that the Ulba Metallurgical Plant is considered as the best site for it in Kazakhstan. The draft plan how to organize experimental studies of irradiated beryllium disposals in Kazakhstan involving National Nuclear Center, National University (Almaty), JSC ''Ulba Metallurgical Plant'' (Ust-Kamenogorsk) would be presented in this paper as well as proposals to arrange international collaboration in that field through ISTC (International Science Technology Center, Moscow). (author)

  9. Metastable defects in beryllium oxide crystals

    International Nuclear Information System (INIS)

    The metastable luminescence centers of regular lattice are investigated in binary beryllium oxide crystals. Beryllium oxide hexagonal crystals are the simplest among low-symmetry oxide scintillators and serve as a model system. The anisotropy of energy transformation and transfer is analyzed

  10. Investigation of beryllium/steam interaction

    Energy Technology Data Exchange (ETDEWEB)

    Chekhonadskikh, A.M.; Vurim, A.D.; Vasilyev, Yu.S.; Pivovarov, O.S. [Inst. of Atomic Energy National Nuclear Center of the Republic of Kazakstan Semipalatinsk (Kazakhstan); Shestakov, V.P.; Tazhibayeva, I.L.

    1998-01-01

    In this report program on investigations of beryllium emissivity and transient processes on overheated beryllium surface attacked by water steam to be carried out in IAE NNC RK within Task S81 TT 2096-07-16 FR. The experimental facility design is elaborated in this Report. (author)

  11. Modeling of hydrogen interactions with beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Longhurst, G.R. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States)

    1998-01-01

    In this paper, improved mathematical models are developed for hydrogen interactions with beryllium. This includes the saturation effect observed for high-flux implantation of ions from plasmas and retention of tritium produced from neutronic transmutations in beryllium. Use of the models developed is justified by showing how they can replicated experimental data using the TMAP4 tritium transport code. (author)

  12. Investigations of the ternary system beryllium-carbon-tungsten and analyses of beryllium on carbon surfaces; Untersuchung des ternaeren Systems Beryllium-Kohlenstoff-Wolfram und Betrachtungen von Beryllium auf Kohlenstoffoberflaechen

    Energy Technology Data Exchange (ETDEWEB)

    Kost, Florian

    2009-05-25

    . Depending on the layer sequence, carbide formation is complete in the temperature range between 570 and 770 K. Be{sub 2}W alloy formation only takes place if further metallic beryllium is available after carbide formation. Be{sub 2}C and Be{sub 2}W dissociate at temperatures T>1170 K. Based on RBS analysis of C/Be/W systems of several 100 nm thickness, the concentration dependent diffusion coefficient for Be in W was determined. Only Be{sub 12}W formation was observed due to the large beryllium reservoir. Carbide formation (Be{sub 2}C) is not observed until the alloy formation is completed. Furthermore, the first successful depth-resolved XPS measurements were performed on ternary layer systems using synchrotron radiation. The reactions in the ternary system are restricted to compounds that are already known from binary system investigations. No further Be, C, W-containing species are detected. Beryllium carbide is dominant in the system as long as it does not dissociate. (orig.)

  13. Assessment of LANL beryllium waste management documentation

    International Nuclear Information System (INIS)

    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

  14. Beryllium for fusion application - recent results

    Science.gov (United States)

    Khomutov, A.; Barabash, V.; Chakin, V.; Chernov, V.; Davydov, D.; Gorokhov, V.; Kawamura, H.; Kolbasov, B.; Kupriyanov, I.; Longhurst, G.; Scaffidi-Argentina, F.; Shestakov, V.

    2002-12-01

    The main issues for the application of beryllium in fusion reactors are analyzed taking into account the latest results since the ICFRM-9 (Colorado, USA, October 1999) and presented at 5th IEA Be Workshop (10-12 October 2001, Moscow Russia). Considerable progress has been made recently in understanding the problems connected with the selection of the beryllium grades for different applications, characterization of the beryllium at relevant operational conditions (irradiation effects, thermal fatigue, etc.), and development of required manufacturing technologies. The key remaining problems related to the application of beryllium as an armour in near-term fusion reactors (e.g. ITER) are discussed. The features of the application of beryllium and beryllides as a neutron multiplier in the breeder blanket for power reactors (e.g. DEMO) in pebble-bed form are described.

  15. BERYLLIUM MEASUREMENT IN COMMERCIALLY AVAILABLE WET WIPES

    Energy Technology Data Exchange (ETDEWEB)

    Youmans-Mcdonald, L.

    2011-02-18

    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.

  16. Postirradiation examination of beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Gelles, D.S. [Pacific Northwest National Lab., Richland, WA (United States)

    1998-03-01

    Postirradiation examinations of COBRA-1A beryllium pebbles irradiated in the EBR-II fast reactor at neutron fluences which generated 2700--3700 appm helium have been performed. Measurements included density change, optical microscopy, scanning electron microscopy, and transmission electron microscopy. The major change in microstructure is development of unusually shaped helium bubbles forming as highly non-equiaxed thin platelet-like cavities on the basal plane. Measurement of the swelling due to cavity formation was in good agreement with density change measurements.

  17. On the discontinuous precipitation reaction and solute redistribution in a Cu-15%Ni-8%Sn alloy

    International Nuclear Information System (INIS)

    Optical and transmission electron microscopy studies have been undertaken in order to clarify some morphological aspects of the discontinuous precipitation (DP) reaction in a Cu-15Ni-8Sn (wt.%) alloy in the temperature range 800-950 K. The DP reaction proceeds in the ternary Cu-Ni-Sn system relatively fast (in binary Cu-Ni alloy is not present) with typical morphological features like change of growth direction, appearance and disappearance of solute-rich γ lamellae. A fine continuous precipitation of single Ni and Sn-rich phase was also evidenced within the solute-depleted α lamellae. An energy-dispersive X-ray analysis showed the level of partitioning of the alloying elements. Most of the Ni and Sn is located in the γ lamellae. However, the formula of the γ lamellae is still close to (Cu3Sn), which indicates that some Cu atoms are replaced by Ni

  18. A Theoretical Investigation on the Reaction Mechanism of the C8H+·10 Side-Chain Decomposition Processes

    Institute of Scientific and Technical Information of China (English)

    CHENG Xue-Li; ZHAO Yan-Yun; LI Feng

    2008-01-01

    The dissociation of ethylbenzene cation C8H+·10 served as a prototype to investigate the decompasition mechanisms of alkylbenzene cations.The reactions of C8H+·10 decomposition reaction system have been studied extensively at the B3L YP/6-311++G** level with Gaussion 98 package.The chain reaction of C8H+·10 dissociation is initiated by C-H bond rupture.All reaction channels were fully investigated with the vibrational mode analysis to confirm the transition states and reveal the reaction mechanism.The energetically most favorable pathway is C8H+·10→TS4→·P2+H· and the channel ieading to C8H+·10 and C2H4 is also competitive.

  19. Technical issues for beryllium use in fusion blanket applications

    International Nuclear Information System (INIS)

    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

  20. 8He cluster structure studied by recoil proton tagged knockout reaction

    Science.gov (United States)

    Ye, Y.; Cao, Z.; Xiao, J.; Jiang, D.; Zheng, T.; Hua, H.; Ge, Y.; Li, X.; Lou, J.; Li, Q.; Lv, L.; Qiao, R.; You, H.; Chen, R.; Sakurai, H.; Otsu, H.; Li, Z.; Nishimura, M.; Sakaguchi, S.; Baba, H.; Togano, Y.; Yoneda, K.; Li, C.; Wang, S.; Wang, H.; Li, K.; Nakayama, Y.; Kondo, Y.; Deguchi, S.; Sato, Y.; Tshoo, K.

    2013-04-01

    Knockout reaction experiment for 8He at 82.3 MeV/u on Hydrogen target was carried out at the RIPS beam line in RIKEN. Recoil protons were detected in coincidence with the forward moving core fragments and neutrons. The quasi-free knockout mechanism is identified through the polar angle correlation and checked by various kinematics conditions. The absolute differential cross sections for 6He core cluster are obtained and compared with the simple Glauber model calculations. The extracted spectroscopic factor is close to unity and a shrinking of the cluster size is evidenced.

  1. 8He cluster structure studied by recoil proton tagged knockout reaction

    International Nuclear Information System (INIS)

    Knockout reaction experiment for 8He at 82.3 MeV/u on Hydrogen target was carried out at the RIPS beam line in RIKEN. Recoil protons were detected in coincidence with the forward moving core fragments and neutrons. The quasi-free knockout mechanism is identified through the polar angle correlation and checked by various kinematics conditions. The absolute differential cross sections for 6He core cluster are obtained and compared with the simple Glauber model calculations. The extracted spectroscopic factor is close to unity and a shrinking of the cluster size is evidenced.

  2. Study of the 7Be(p,γ)8B and 7Li(n,γ)8Li capture reactions using the shell model embedded in the continuum

    International Nuclear Information System (INIS)

    The realistic shell model which includes the coupling between many-particle (quasi-)bound states and the continuum of one-particle scattering states is applied to the spectroscopy of mirror nuclei: 8B and 8Li, as well as to the description of low energy cross sections (the astrophysical S factors) in the capture reactions: 7Be(p,γ)8B and 7Li(n,γ)8Li. (author)

  3. Steam chemical reactivity of plasma-sprayed beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, R.A.; Pawelko, R.J.; Smolik, G.R. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.; Castro, R.G. [Los Alamos National Lab., NM (United States)

    1998-07-01

    Plasma-spraying with the potential for in-situ repair makes beryllium a primary candidate for plasma facing and structural components in experimental magnetic fusion machines. Deposits with good thermal conductivity and resistance to thermal cycling have been produced with low pressure plasma-spraying (LPPS). A concern during a potential accident with steam ingress is the amount of hydrogen produced by the reactions of steam with hot components. In this study the authors measure the reaction rates of various deposits produced by LPPS with steam from 350 C to above 1,000 C. They correlate these reaction rates with measurements of density, open porosity and BET surface areas. They find the reactivity to be largely dependent upon effective surface area. Promising results were obtained below 600 C from a 94% theoretical dense (TD) deposit with a BET specific surface area of 0.085 m{sup 2}/g. Although reaction rates were higher than those for dense consolidated beryllium they were substantially lower, i.e., about two orders of magnitude, than those obtained from previously tested lower density plasma-sprayed deposits.

  4. Fluorimetric method for determination of Beryllium

    International Nuclear Information System (INIS)

    The old fluorimetric method for the determination of Beryllium, based essentially on the fluorescence of the Beryllium-Morine complex in a strongly alkaline solution, is still competitive and stands the comparison with more modern methods or at least three reasons: in the presence of solid or gaseous samples (powders), the times necessary to finalize an analytic determination are comparable since the stage of the process which lasts the longest is the mineralization of the solid particles containing Beryllium, the cost of a good fluorimeter is by far Inferior to the cost, e. g., of an Emission Spectrophotometer provided with ICP torch and magnets for exploiting the Zeeman effect and of an Atomic absorption Spectrophotometer provided with Graphite furnace; it is possible to determine, fluorimetrically, rather small Beryllium levels (about 30 ng of Beryllium/sample), this potentiality is more than sufficient to guarantee the respect of all the work safety and hygiene rules now in force. The study which is the subject of this publication is designed to the analysis procedure which allows one to reach good results in the determination of Beryllium, chiefly through the control and measurement of the interference effect due to the presence of some metals which might accompany the environmental samples of workshops and laboratories where Beryllium is handled, either at the pure state or in its alloys. The results obtained satisfactorily point out the merits and limits of this analytic procedure

  5. Recommended design correlations for S-65 beryllium

    International Nuclear Information System (INIS)

    The properties of tritium and helium behavior in irradiated beryllium are reviewed, along with the thermal-mechanical properties needed for ITER design analysis. Correlations are developed to describe the performance of beryllium in a fusion reactor environment. While this paper focuses on the use of beryllium as a plasma-facing component (PFC) material, the correlations presented here can also be used to describe the performance of beryllium as a neutron multiplier for a tritium breeding blanket. The performance properties for beryllium are subdivided into two categories: properties which do not change with irradiation damage to the bulk of the material; and properties which are degraded by neutron irradiation. The irradiation-independent properties described within are: thermal conductivity, specific heat capacity, thermal expansion, and elastic constants. Irradiation-dependent properties include: yield strength, ultimate tensile strength, plastic tangent modulus, uniform and total tensile elongation, thermal and irradiation-induced creep strength, He-induced swelling and tritium retention/release. The approach taken in developing properties correlations is to describe the behavior of dense, pressed S-65 beryllium -- the material chosen for ITER PFC application -- as a function of temperature. As there are essentially no data on the performance of porous and/or irradiated S-65 beryllium, the degradation of properties with as-fabricated porosity and irradiation are determined from the broad data base on S-200F, as well as other types and grades, and applied to S-65 beryllium by scaling factors. The resulting correlations can be used for Be produced by vacuum hot pressing (VHP) and cold-pressing (CP)/sintering(S)/hot-isostatic-pressing (HIP). The performance of plasma-sprayed beryllium is discussed but not quantified

  6. Recommended design correlations for S-65 beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Billone, M.C. [Argonne National Lab., IL (United States)

    1995-09-01

    The properties of tritium and helium behavior in irradiated beryllium are reviewed, along with the thermal-mechanical properties needed for ITER design analysis. Correlations are developed to describe the performance of beryllium in a fusion reactor environment. While this paper focuses on the use of beryllium as a plasma-facing component (PFC) material, the correlations presented here can also be used to describe the performance of beryllium as a neutron multiplier for a tritium breeding blanket. The performance properties for beryllium are subdivided into two categories: properties which do not change with irradiation damage to the bulk of the material; and properties which are degraded by neutron irradiation. The irradiation-independent properties described within are: thermal conductivity, specific heat capacity, thermal expansion, and elastic constants. Irradiation-dependent properties include: yield strength, ultimate tensile strength, plastic tangent modulus, uniform and total tensile elongation, thermal and irradiation-induced creep strength, He-induced swelling and tritium retention/release. The approach taken in developing properties correlations is to describe the behavior of dense, pressed S-65 beryllium -- the material chosen for ITER PFC application -- as a function of temperature. As there are essentially no data on the performance of porous and/or irradiated S-65 beryllium, the degradation of properties with as-fabricated porosity and irradiation are determined from the broad data base on S-200F, as well as other types and grades, and applied to S-65 beryllium by scaling factors. The resulting correlations can be used for Be produced by vacuum hot pressing (VHP) and cold-pressing (CP)/sintering(S)/hot-isostatic-pressing (HIP). The performance of plasma-sprayed beryllium is discussed but not quantified.

  7. Research of flaw assessment methods for beryllium reflector elements

    International Nuclear Information System (INIS)

    Reflector elements made from metal beryllium is widely used as neutron reflectors to increase neutron flux in test reactors. When beryllium reflector elements are irradiated by neutron, bending of reflector elements caused by swelling occurs, and beryllium reflector elements must be replaced in several years. In this report, literature search and investigation for non-destructive inspection of Beryllium and experiments for Preliminary inspection to establish post irradiation examination method for research of characteristics of metal beryllium under neutron irradiation were reported. (author)

  8. Preliminary proposal for a beryllium technology program for fusion applications

    International Nuclear Information System (INIS)

    The program was designed to provide the answers to the critical issues of beryllium technology needed in fusion blanket designs. The four tasks are as follows: (1) Beryllium property measurements needed for fusion data base. (2) Beryllium stress relaxation and creep measurements for lifetime modelling calculations. (3) Simplified recycle technique development for irradiated beryllium. (4) Beryllium neutron multiplier measurements using manganese bath absolute calibration techniques

  9. On the discontinuous dissolution reaction in a Mg-8 wt.% Al alloy

    Energy Technology Data Exchange (ETDEWEB)

    Bradai, D.; Kadi-Hanifi, M. [Universite des Sciences et de la Technologie Houari-Boumediene, Alger (Algeria); Zieba, P. [Polish Academy of Sciences, Cracow (Poland); Gust, W. [Stuttgart Univ. (Germany)

    1998-12-01

    The present studies of a Mg-8 wt.% Al alloy have shown that the discontinuous precipitation reaction is occurring during ageing at 500 K. A subsequent dissolution heat treatment at 625 K revealed that the dissolution process occurs in the discontinuous mode by receding of the former reaction front of the discontinuous precipitation towards the position of the original grain boundary. The solid solution resulting from the discontinuous dissolution process is very inhomogeneous. As the theoretical calculations proved the differences in the Al content can be as large as 15 wt.%. (orig.) [Deutsch] Die durchgefuehrten Untersuchungen zeigen, dass in der Legierung Mg-8 Gew.-% Al bei einer Temperatur von 500 K die diskontinuierliche Ausscheidung sehr ausgepraegt auftritt. Bei einer anschliessenden Auslagerung bei 625 K tritt die diskontinuierliche Aufloesung in Erscheinung. Dabei wandert die Reaktionsfront der diskontinuierlichen Ausscheidung rueckwaerts in Richtung auf die urspruengliche Korngrenze zu, an der sie gestartet ist. Der dabei gebildete Mischkristall ist sehr inhomogen. Wie theoretische Berechnungen zeigen, ist der Al-Gehalt an den ehemaligen Stellen der Al{sub 12}M{sub 17}-Lamellen bis zu 15 Gew.-% hoeher als an den Stellen dazwischen. (orig.)

  10. Iron-containing phases in commercial beryllium

    International Nuclear Information System (INIS)

    The effect of hot and cold rolling with subsequent heat treatment on the interrelation of iron-containing phases and texture in commercial beryllium is considered. Using the Moessbauer microscopy it has been established that iron impurities are present both in solid solution and in the composition of intermetallide AlFeBe4 the texture for iron solid solution in beryllium is determined. Beryllium quenching results in nearly complete disappearance of intermetallic phase and iron transfers into substitutional solid solution. Further cold rolling does not result in any phase transformation

  11. Development of Interatomic Potentials for Beryllium

    International Nuclear Information System (INIS)

    Full text of publication follows: To be able to benefit from fusion as a clean and safe power source, we need a comprehensive understanding of the dynamic region of a fusion reactor. Knowing the interplay between the fuel plasma and the reactor components, such as the first wall and the divertor, one can minimize the resulting degradation. The atom-level mechanisms behind the reactions, (e.g. erosion and redeposition) are, however, not accessible to experiments. Hence, computational methods, including molecular dynamics (MD) simulations, are needed. The interactions in a system of particles are within MD described by an interatomic potential. The study of reactor processes requires models for the mixed interaction between the first wall and divertor materials beryllium, carbon and tungsten, as well as for the interaction of these with hydrogen. The absence of proper models for the Be system motivated us to develop potentials for pure Be, Be-C, Be-W and Be-H. We present a Tersoff-like bond order potential for pure Be and the same formalism applied to Be-C and Be-H. The performance of the potentials is discussed and an outlook for the remaining potential is also given. (authors)

  12. On solid-phase interaction of beryllium oxide with mullite

    International Nuclear Information System (INIS)

    The interaction of beryllium oxide with mullite has been analyzed thermodynamically. It is shown that the reaction between the above substances must proceed with separation of chrysoberyl but without yielding phenacite, which is inconsistent with some data published. It has been found experimentally that the interaction of pure BeO and mullite is described by equation 3Al2Ox2SiO2+3BeO→3BeAl2O4+2SiO2

  13. Dissolution of FB-Line Residues Containing Beryllium Metal

    International Nuclear Information System (INIS)

    Scrap materials containing plutonium (Pu) metal are currently being transferred from the FB Line vault to HB Line for dissolution and subsequent disposition through the H-Canyon facility. Some of the items scheduled for dissolution contain both Pu and beryllium (Be) metal as a composite material. The Pu and Be metals were physically separated to minimize the amount of Be associated with the Pu; however, the dissolution flowsheet was required to dissolve small amounts of Be combined with the Pu metal using a dissolving solution containing nitric acid (HNO3) and potassium fluoride (KF). Since the dissolution of Pu metal in HNO3/fluoride (F-) solutions is well understood, the primary focus of the experimental program was the dissolution of Be metal. Initially, small-scale experiments were used to measure the dissolution rate of Be metal foils using conditions effective for the dissolution of Pu metal. The experiments demonstrated that the dissolution rate was nearly independent of the HNO3 concentration over the limited range of investigation and only a moderate to weak function of the F- concentration. The effect of temperature was more pronounced, significantly increasing the dissolution rate between 40 and 105 degrees C. The offgas from three Be metal foil dissolutions was collected and characterized. The production of hydrogen (H2) was found to be sensitive to the HNO3 concentration, decreasing by a factor of approximately two when the HNO3 was increased from 4 to 8 M. This result is consistent with the dissolution mechanism shifting away from a typical metal/acid reaction toward increased production of nitrogen oxides by nitrate (NO3-) oxidation

  14. Palladium-catalysed reactions of 8-hydroxy- and 8-benzyloxy-5,7-diiodoquinoline under aminocarbonylation conditions

    OpenAIRE

    Takács, Attila; Szilágyi, Antal; Ács, Péter; Márk, László; Peixoto, Andreia F.; Mariette M. Pereira; Kollár, László

    2011-01-01

    Various 5-carboxamido-7-iodo-8-benzyloxyquinolines were synthesised via selective aminocarbonylation of 5,7-diiodo-8-benzyloxyquinoline in the presence of ‘in situ’ generated palladium(0) catalysts. Under similar conditions (50 °C, 80 bar CO), 5,7-bis(N-tert-butyl-glyoxylamido)-8-hydroxyquinoline was obtained using tert-butylamine as N-nucleophile. The unprotected 5,7-diiodo-8-hydroxyquinoline underwent dehydroiodination resulting in 8-hydroxyquinoline as the major product.

  15. Chronic Beryllium Disease Prevention Program Report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S

    2012-03-29

    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.'

  16. Structural Basis of Chronic Beryllium Disease: Linking Allergic Hypersensitivity and Autoimmunity

    OpenAIRE

    Clayton, Gina M.; Wang, Yang; Crawford, Frances; Novikov, Andrey; Wimberly, Brian T.; Kieft, Jeffrey S.; Falta, Michael T.; Bowerman, Natalie A.; Marrack, Philippa; Fontenot, Andrew P.; Dai, Shaodong; John W Kappler

    2014-01-01

    T cell-mediated hypersensitivity to metal cations is common in humans. How the T cell antigen receptor (TCR) recognizes these cations bound to a major histocompatibility complex (MHC) protein and self-peptide is unknown. Individuals carrying the MHCII allele, HLA-DP2, are at risk for chronic beryllium disease (CBD), a debilitating inflammatory lung condition caused by the reaction of CD4 T cells to inhaled beryllium. We show here that the T cell ligand is created when a Be2+ cation becomes bu...

  17. Phase equilibria, compatibility studies and thermal properties of beryllium systems

    International Nuclear Information System (INIS)

    The quality control of commercial beryllium, the examinations of the phase equilibria in beryllium systems as well as the broad field of incompatibility and the reaction kinetics of beryllium with other materials necessitate a sophisticated method for the analysis of this element in micrometer areas. A powerful tool is the wavelength dispersive X-ray microanalyser. Therefore, a commercial synthetic Mo-B4C multilayer X-ray diffracting device with 2 d = 22.2 nm periodicity was used to extend X-ray microanalysis to the ultra-light elements Be and B in an existing instrument. The spectrometer covers a wavelength range between 5.2 and 13 nm. The wavelength of the Be Kα emission line from elemental Be is λ = 11.35 nm and the full width at half maximum is ΔE = 7.2 eV. The optimum working voltage Uo is 10 kV for moderate X-ray mass absorption of the targets. The determination of Be in oxides is less favourable owing to the high mass absorption. Uo has to be reduced to 5 kV. The chemical shift of the Be Kα line in BeO is Δλ = + 0.3 nm relative to pure Be. Beryllium pebbles are foreseen as neutron multipliers in future fusion reactor blanket concepts. Industrial intermediate Be products which had been produced by a modified Kroll process and subsequent reduction of BeF2 using Mg were investigated by X-ray microanalysis. The following precipitates in the Be matrix of 2 mm pebbles partially annealed up to 790 C could be detected: (Mg, Zr, U) Be13, MgBe13, Mg2Si, Al2Mg3 and (Fe, Cr) alloys. The maximum solubility of selected metallic impurities in beryllium annealed at 800 C is: 0.06 mass % Fe, 0.03 mass % Al, 0.02 mass % Si, 5Fe2, Be2C and Cr-Fe-Si were observed in specimens annealed between 870 and 690 C. It is interesting that Al5Fe2 precipitates were observed; however, the phase AlFeBe4 that would have been expected according to the phase diagram of the ternary Al-Be-Fe system was not found. Probably the Fe/Al ratio is too low for AlFeBe4 formation. The high annealing

  18. Lithium-Beryllium-Boron : Origin and Evolution

    OpenAIRE

    Vangioni-Flam, Elisabeth; Casse, Michel; Audouze, Jean

    1999-01-01

    The origin and evolution of Lithium-Beryllium-Boron is a crossing point between different astrophysical fields : optical and gamma spectroscopy, non thermal nucleosynthesis, Big Bang and stellar nucleosynthesis and finally galactic evolution. We describe the production and the evolution of Lithium-Beryllium-Boron from Big Bang up to now through the interaction of the Standard Galactic Cosmic Rays with the interstellar medium, supernova neutrino spallation and a low energy component related to...

  19. Beryllium concentration in pharyngeal tonsils in children

    Directory of Open Access Journals (Sweden)

    Ewa Nogaj

    2014-06-01

    Full Text Available Power plant dust is believed to be the main source of the increased presence of the element beryllium in the environment which has been detected in the atmospheric air, surface waters, groundwater, soil, food, and cigarette smoke. In humans, beryllium absorption occurs mainly via the respiratory system. The pharyngeal tonsils are located on the roof of the nasopharynx and are in direct contact with dust particles in inhaled air. As a result, the concentration levels of beryllium in the pharyngeal tonsils are likely to be a good indicator of concentration levels in the air. The presented study had two primary aims: to investigate the beryllium concentration in pharyngeal tonsils in children living in southern Poland, and the appropriate reference range for this element in children’s pharyngeal tonsils. Pharyngeal tonsils were extracted from a total of 379 children (age 2–17 years, mean 6.2 ± 2.7 years living in southern Poland. Tonsil samples were mineralized in a closed cycle in a pressure mineralizer PDS 6, using 65% spectrally pure nitric acid. Beryllium concentration was determined using the ICP-AES method with a Perkin Elmer Optima 5300DVTM. The software Statistica v. 9 was used for the statistical analysis. It was found that girls had a significantly greater beryllium concentration in their pharyngeal tonsils than boys. Beryllium concentration varies greatly, mostly according to the place of residence. Based on the study results, the reference value for beryllium in pharyngeal tonsils of children is recommended to be determined at 0.02–0.04 µg/g.

  20. Beryllium Project: developing in CDTN of uranium dioxide fuel pellets with addition of beryllium oxide to increase the thermal conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ricardo Alberto Neto; Camarano, Denise das Merces; Miranda, Odair; Grossi, Pablo Andrade; Andrade, Antonio Santos; Queiroz, Carolinne Mol; Gonzaga, Mariana de Carvalho Leal, E-mail: ranf@cdtn.br, E-mail: dmc@cdtn.br, E-mail: odairm@cdtn.br, E-mail: pabloag@cdtn.br, E-mail: antdrade@gmail.com, E-mail: carolmol@gmail.com, E-mail: mari_clgonzaga@hotmail.com [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Pampulha, MG (Brazil)

    2013-07-01

    Although the nuclear fuel currently based on pellets of uranium dioxide be very safe and stable, the biggest problem is that this material is not a good conductor of heat. This results in an elevated temperature gradient between the center and its lateral surface, which leads to a premature degradation of the fuel, which restricts the performance of the reactor, being necessary to change the fuel before its full utilization. An increase of only 5 to 10 percent in its thermal conductivity, would be a significant increase. An increase of 50 percent would be a great improvement. A project entitled 'Beryllium Project' was developed in CDTN - Centro de Desenvolvimento da Tecnologia Nuclear, which aimed to develop fuel pellets made from a mixture of uranium dioxide microspheres and beryllium oxide powder to obtain a better heat conductor phase, filling the voids between the microspheres to increase the thermal conductivity of the pellet. Increases in the thermal conductivity in the range of 8.6% to 125%, depending on the level of addition employed in the range of 1% to 14% by weight of beryllium oxide, were obtained. This type of fuel promises to be safer than current fuels, improving the performance of the reactor, in addition to last longer, resulting in great savings. (author)

  1. Quantitative differential thermal analysis study of the U/sub 3/O/sub 8/-Al thermite reaction

    Energy Technology Data Exchange (ETDEWEB)

    Pasto, A.E.; Copeland, G.L.; Martin, M.M.

    1980-06-01

    Concerns about proliferation resistance of nuclear fuel cycles and fuels have prompted a reinvestigation of U/sub 3/O/sub 8/-Al cermet fuels currently being used in research and test reactors. In particular, higher loadings of U/sub 3/O/sub 8/ are being considered. These new fuel compositions are in the region of maximum possible thermal energy release from the high-temperature thermite reaction between the U/sub 3/O/sub 8/ and aluminum components. This study was initiated to quantitatively measure the amount of reaction heat evolved. A differential thermal analysis system was calibrated with materials of known heat of reaction. Subsequently, specimens of high-uranium-loaded U/sub 3/O/sub 8/-Al powder mixtures were analyzed. Thermite reaction heat measured for these specimens was much lower than expected. Possible reason(s) for this behavior are discussed in the report.

  2. Tritium release from neutron irradiated beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reactortechnik

    1998-01-01

    One of the most important open issues related to beryllium for fusion applications refers to the kinetics of the tritium release as a function of neutron fluence and temperature. The EXOTIC-7 as well as the `Beryllium` experiments carried out in the HFR reactor in Petten are considered as the most detailed and significant tests for investigating the beryllium response under neutron irradiation. This paper reviews the present status of beryllium post-irradiation examinations performed at the Forschungszentrum Karlsruhe with samples from the above mentioned irradiation experiments, trying to elucidate the tritium release controlling processes. In agreement with previous studies it has been found that release starts at about 500-550degC and achieves a maximum at about 700-750degC. The observed release at about 500-550degC is probably due to tritium escaping from chemical traps, while the maximum release at about 700-750degC is due to tritium escaping from physical traps. The consequences of a direct contact between beryllium and ceramics during irradiation, causing tritium implanting in a surface layer of beryllium up to a depth of about 40 mm and leading to an additional inventory which is usually several times larger than the neutron-produced one, are also presented and the effects on the tritium release are discussed. (author)

  3. Solid state bonding of beryllium-copper for an ITER first wall application

    International Nuclear Information System (INIS)

    Several different joint assemblies were evaluated in support of a manufacturing technology for diffusion bonding a beryllium armor tile to a copper alloy heat sink for fusion reactor applications. Because beryllium reacts with all but a few elements to form intermetallic compounds, this study considered several different surface treatments as a means of both inhibiting these reactions and promoting a good diffusion bond between the two substrates. All diffusion bonded assemblies used aluminum or an aluminum-beryllium composite (AlBeMet-150) as the interfacial material in contact with beryllium. In most cases, explosive bonding was utilized as a technique for joining the copper alloy heat sink to an aluminum or AlBeMet-150 substrate, which was subsequently diffusion bonded to an aluminum coated beryllium tile. In this approach, a 250 μm thick titanium foil was used as a diffusion barrier between the copper and aluminum to prevent the formation of Cu-Al intermetallic phases. In all cases, a hot isostatic pressing (HIP) furnace was used in conjunction with canned assemblies in order to minimize oxidation and apply sufficient pressure on the assembly for excellent metal-to-metal contact and subsequent bonding. Several different processing schedules were evaluated during the course of this study; bonded assemblies were produced that failed outside the bond area indicating a 100% joint efficiency. (author)

  4. Solid state bonding of beryllium-copper for an ITER first wall application

    International Nuclear Information System (INIS)

    Several different joint assemblies were evaluated in support of a manufacturing technology for diffusion bonding a beryllium armor tile to a copper alloy heat sink for fusion reactor applications. Because beryllium reacts with all but a few elements to form intermetallic compounds, this study considered several different surface treatments as a means of both inhibiting these reactions and promoting a good diffusion bond between the two substrates. A diffusion bonded assemblies used aluminum or an aluminum-beryllium composite (AlBeMet-150) as the interfacial material in contact with beryllium. In most cases, explosive bonding was utilized as a technique for joining the copper alloy heat sink to an aluminum or AlBeMet-150 substrate, which was subsequently diffusion bonded to an aluminum coated beryllium tile. In this approach, a 250 microm thick titanium foil was used as a diffusion barrier between the copper and aluminum to prevent the formation of Cu-Al intermetallic phases. In all cases, a hot isostatic pressing (HIP) furnace was used in conjunction with canned assemblies in order to minimize oxidation and apply sufficient pressure on the assembly for excellent metal-to-metal contact and subsequent bonding. Several different processing schedules were evaluated during the course of this study; bonded assemblies were produced that failed outside the bond area indicating a 100% joint efficiency

  5. Removal of Beryllium Material during Decommissioning of a Slowpoke Reactor, Toronto, Canada

    International Nuclear Information System (INIS)

    The Slowpoke (acronym for Safe LOW-POwer Kritical Experiment) is a low energy, tank-in-pool type nuclear research reactor designed by the Atomic Energy of Canada Limited in the late 1960s. The fuel cage is surrounded by a beryllium assembly at the bottom of a water pool about 6 m deep. The beryllium reflects neutrons back into the core. Basically, the reactor is a subcritical mass of fuel, which the surrounding beryllium makes critical. The rate of reaction is controlled by inserting a neutron absorbing cadmium rod. Slowpokes have a maximum power of 100 kW and normally operate at about 20 kW. The University of Toronto SLOWPOKE-2 Reactor research services ended in December 1998, and the reactor was finally defuelled in June 2000. On 10 November 2000, the Canadian Nuclear Safety Commission (CNSC) issued the decommissioning licence to the University of Toronto for its SLOWPOKE-2 Nuclear Reactor Facility. The reactor decommissioning was completed in January 2001. The beryllium material was to have been shipped under the operating licence, but actually it was shipped under the decommissioning licence. The CNSC revoked the decommissioning licence for the University of Toronto SLOWPOKE-2 Reactor Facility on 24 February 2012, and the site was returned to the university for unrestricted site use. The following is a description of the incident involving the beryllium material management

  6. Solid state bonding of beryllium-copper for an ITER first wall application

    Energy Technology Data Exchange (ETDEWEB)

    Odegard, B.C. Jr.; Cadden, C.H. [Sandia National Labs., Livermore, CA (United States)

    1998-01-01

    Several different joint assemblies were evaluated in support of a manufacturing technology for diffusion bonding a beryllium armor tile to a copper alloy heat sink for fusion reactor applications. Because beryllium reacts with all but a few elements to form intermetallic compounds, this study considered several different surface treatments as a means of both inhibiting these reactions and promoting a good diffusion bond between the two substrates. All diffusion bonded assemblies used aluminum or an aluminum-beryllium composite (AlBeMet-150) as the interfacial material in contact with beryllium. In most cases, explosive bonding was utilized as a technique for joining the copper alloy heat sink to an aluminum or AlBeMet-150 substrate, which was subsequently diffusion bonded to an aluminum coated beryllium tile. In this approach, a 250 {mu}m thick titanium foil was used as a diffusion barrier between the copper and aluminum to prevent the formation of Cu-Al intermetallic phases. In all cases, a hot isostatic pressing (HIP) furnace was used in conjunction with canned assemblies in order to minimize oxidation and apply sufficient pressure on the assembly for excellent metal-to-metal contact and subsequent bonding. Several different processing schedules were evaluated during the course of this study; bonded assemblies were produced that failed outside the bond area indicating a 100% joint efficiency. (author)

  7. H-3 and Li-6 poisoning of the Maria reactor beryllium matrix

    International Nuclear Information System (INIS)

    This report discusses methods used to evaluate Li-6 and He-3 poison concentrations, initiated by Be-9(n, α) reaction in the beryllium blocks of the Maria reactor. The results based on ENDF/B-VI neutron cross sections, 3D diffusion neutron fluxes, and solutions to the differential equations which describe the time-dependent poison concentrations as function of reactor operation and shutdown periods. MCNP Monte Carlo calculations were used to verify calculated poison levels for observed critical configurations. Previous evaluations used somewhat less refined methods based on asymptotic solutions for the poison concentrations. It was found that Li-6 and He-3 in the beryllium blocks limit the available excess reactivities and alter flux and power distributions. Based on analyses of critical cores, it was determined that poison concentrations need be evaluated for an in-core region and for an excore region and not for each beryllium block. (author)

  8. X-ray drive of beryllium capsule implosions at the National Ignition Facility

    Science.gov (United States)

    Wilson, D. C.; Yi, S. A.; Simakov, A. N.; Kline, J. L.; Kyrala, G. A.; Dewald, E. L.; Tommasini, R.; Ralph, J. E.; Olson, R. E.; Strozzi, D. J.; Celliers, P. M.; Schneider, M. B.; MacPhee, A. G.; Zylstra, A. B.; Callahan, D. A.; Hurricane, O. A.; Milovich, J. L.; Hinkel, D. E.; Rygg, J. R.; Rinderknecht, H. G.; Sio, H.; Perry, T. S.; Batha, S.

    2016-05-01

    National Ignition Facility experiments with beryllium capsules have followed a path begun with “high-foot” plastic capsule implosions. Three shock timing keyhole targets, one symmetry capsule, a streaked backlit capsule, and a 2D backlit capsule were fielded before the DT layered shot. After backscatter subtraction, laser drive degradation is needed to match observed X-ray drives. VISAR measurements determined drive degradation for the picket, trough, and second pulse. Time dependence of the total Dante flux reflects degradation of the of the third laser pulse. The same drive degradation that matches Dante data for three beryllium shots matches Dante and bangtimes for plastic shots N130501 and N130812. In the picket of both Be and CH hohlraums, calculations over-estimate the x-ray flux > 1.8 keV by ∼100X, while calculating the total flux correctly. In beryllium calculations these X-rays cause an early expansion of the beryllium/fuel interface at ∼3 km/s. VISAR measurements gave only ∼0.3 km/s. The X-ray drive on the Be DT capsule was further degraded by an unplanned decrease of 9% in the total picket flux. This small change caused the fuel adiabat to rise from 1.8 to 2.3. The first NIF beryllium DT implosion achieved 29% of calculated yield, compared to CH capsules with 68% and 21%.

  9. Sanitary-hygienic and ecological aspects of beryllium production

    Energy Technology Data Exchange (ETDEWEB)

    Dvinskykh, E.M.; Savchuk, V.V.; Sidorov, V.L.; Slobodin, D.B.; Tuzov, Y.V. [Ulba Metallurgical Plant, Ust-Kamenogorsk (Kazakhstan)

    1998-01-01

    The Report describes An organization of sanitary-hygienic and ecological control of beryllium production at Ulba metallurgical plant. It involves: (1) the consideration of main methods for protection of beryllium production personnel from unhealthy effect of beryllium, (2) main kinds of filters, used in gas purification systems at different process areas, (3) data on beryllium monitoring in water, soil, on equipment. This Report also outlines problems connected with designing devices for a rapid analysis of beryllium in air as well as problems of beryllium production on ecological situation in the town. (author)

  10. In-pile thermocycling testing and post-test analysis of beryllium divertor mockups

    Energy Technology Data Exchange (ETDEWEB)

    Giniatulin, R.; Mazul, I. [Efremov Inst., St. Petersburg (Russian Federation); Melder, R.; Pokrovsky, A.; Sandakov, V.; Shiuchkin, A.

    1998-01-01

    The main damaging factors which impact the ITER divertor components are neutron irradiation, cyclic surface heat loads and hydrogen environment. One of the important questions in divertor mockups development is the reliability of beryllium/copper joints and the beryllium resistance under neutron irradiation and thermal cycling. This work presents the experiment, where neutron irradiation and thermocyclic heat loads were applied simultaneously for two beryllium/copper divertor mockups in a nuclear reactor channel to simulate divertor operational conditions. Two mockups with different beryllium grades were mounted facing each other with the tantalum heater placed between them. This device was installed in the active zone of the nuclear reactor SM-2 (Dimitrovgrad, Russia) and the tantalum block was heated by neutron irradiation up to a high temperature. The main part of the heat flux from the tantalum surface was transported to the beryllium surface through hydrogen, as a result the heat flux loaded two mockups simultaneously. The mockups were cooled by reactor water. The device was lowered to the active zone so as to obtain the heating regime and to provide cooling lifted. This experiment was performed under the following conditions: tantalum heater temperature - 1950degC; hydrogen environment -1000 Pa; surface heat flux density -3.2 MW/m{sup 2}; number of thermal cycles (lowering and lifting) -101; load time in each cycle - 200-5000 s; dwell time (no heat flux, no neutrons) - 300-2000 s; cooling water parameters: v - 1 m/s, Tin - 50degC, Pin - 5 MPa; neutron fluence -2.5 x 10{sup 20} cm{sup -2} ({approx}8 years of ITER divertor operation from the start up). The metallographic analysis was performed after experiment to investigate the beryllium and beryllium/copper joint structures, the results are presented in the paper. (author)

  11. Electronic band structure of beryllium oxide

    CERN Document Server

    Sashin, V A; Kheifets, A S; Ford, M J

    2003-01-01

    The energy-momentum resolved valence band structure of beryllium oxide has been measured by electron momentum spectroscopy (EMS). Band dispersions, bandwidths and intervalence bandgap, electron momentum density (EMD) and density of occupied states have been extracted from the EMS data. The experimental results are compared with band structure calculations performed within the full potential linear muffin-tin orbital approximation. Our experimental bandwidths of 2.1 +- 0.2 and 4.8 +- 0.3 eV for the oxygen s and p bands, respectively, are in accord with theoretical predictions, as is the s-band EMD after background subtraction. Contrary to the calculations, however, the measured p-band EMD shows large intensity at the GAMMA point. The measured full valence bandwidth of 19.4 +- 0.3 eV is at least 1.4 eV larger than the theory. The experiment also finds a significantly higher value for the p-to-s-band EMD ratio in a broad momentum range compared to the theory.

  12. Lightweight beryllium wins wings as real heavyweight

    International Nuclear Information System (INIS)

    Development of Be materials with improved strength and ductility levels is possible by exploitation of new consolidation techniques, such as cold and hot isostatic pressing and plasma spraying followed by sintering. Working the vacuum hot pressed billet by cross-rolling or extruding and by forging improves the mechanical properties. The valuable contributions of Be in aerospace and nuclear applications are considered. SNAP-8 and SNAP-10A applications, replacement of an Al alloy on the Minuteman spacer ring by Be, aircraft (flight testing of F-4 Phantom with a Be rudder and actual structural application of Be wrought mill product in F-14 Tomcat) and communication satellite (despin platforms, spinning arms, russ structures) applications are discussed together with instrument applications (guidance systems for Saturn V, Minuteman and the Boeing 747, proportional counters for space-oriented x-ray experiments), Be applications in lunar explorations, expanding use of Be in space applications as a mirror blank material and Be disks for the brakes of giant aircraft. Beryllium has the highest specific heat of all structural metals and it shows chemical inertness to many of the common ocket propellants and their combustion products. Its handicaps are high cost and poor impact behavior. (U.S.)

  13. Beryllium colorimetric detection for high speed monitoring of laboratory environments.

    Science.gov (United States)

    Taylor, Tammy P; Sauer, Nancy N

    2002-08-01

    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

  14. {sup 3}He induced reactions on {sup nat}Ag and {sup 197}Au at 1.8, 3.6 and 4.8 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Brzychczyk, J. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee]|[Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Pollacco, E.C.; Volant, C.; Legrain, R. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Kwiatkowski, K.; Morley, K.B.; Renshaw-Foxford, E.; Bracken, D.S.; Viola, V.E.; Yoder, N.R. [Indiana Univ., Bloomington, IN (United States). Dept. of Chemistry] [and others

    1995-03-01

    The {sup 3}He induced reactions on Ag and Au are studied using a large solid angle and low energy threshold detector array. The data show consistency with intranuclear cascade and expanding emitting source description. Charge moment analysis is presented. (author). 18 refs., 8 figs.

  15. 3He induced reactions on natAg and 197Au at 1.8, 3.6 and 4.8 GeV

    International Nuclear Information System (INIS)

    The 3He induced reactions on Ag and Au are studied using a large solid angle and low energy threshold detector array. The data show consistency with intranuclear cascade and expanding emitting source description. Charge moment analysis is presented. (author). 18 refs., 8 figs

  16. Study on the 8He ground state via 8He(p, d)7He and 8He(p, t)6He reaction at 82.3 MeV/nucleon

    International Nuclear Information System (INIS)

    The differential cross sections for reactions 8He(p, d)7Heg.s and 8He(p, t)6He2+ were measured by the coincidence of d + 6 He and t + 4He in a wide angular range from 15 to 130 degree in the center-of-mass system. The cross sections of the 8He(p, t)6Heg.s reaction were extremely lower than that of 8He(p, t)6He2+ reaction, and was not obtained from the present data. The experimental results were compared to the preliminary theoretical calculations in the frame of adiabatic distorted-wave approximation with the code Fresco. The results show that the configuration of (1p3/2)2(1p1/2)2 may have some probability in the ground state wave function of 8He. The cluster structure of 8He = 5H + 3H could not be neglected.

  17. The formation and decay of superheavy nuclei produced in sup 4 sup 8 Ca-induced reactions

    CERN Document Server

    Kumar, S; Gupta, R K; Münzenberg, G; Scheid, W

    2003-01-01

    The formation of superheavy nuclei in sup 4 sup 8 Ca+ sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 8 U, sup 2 sup 4 sup 2 sup , sup 2 sup 4 sup 4 Pu and sup 2 sup 4 sup 8 Cm reactions and their subsequent decay are studied within the quantum mechanical fragmentation theory (QMFT) and the QMFT-based preformed cluster decay model (PCM) of Gupta and collaborators. According to QMFT, all these sup 4 sup 8 Ca-induced reactions are cold fusion reactions with relative excitation energies larger than those for the Pb-induced cold fusion reactions and smaller than those for the lighter beam, i.e. Mg, Si or S-induced hot fusion reactions. The same reactions were first suggested by Gupta et al in 1977 on the basis of QMFT, and this study re-establishes the same result. In fact, for such heavy isotopes of Z = 110 to 116, sup 5 sup 0 Ca is shown to be a better beam for cold fusion, but sup 5 sup 0 Ca is a radioactive nucleus. The alpha-decay half-lives of these nuclei after 3n and/or 4n evaporations, i.e. of the evaporation resi...

  18. Long-term follow-up of beryllium sensitized workers from a single employer

    Directory of Open Access Journals (Sweden)

    Curtis Anne M

    2010-01-01

    Full Text Available Abstract Background Up to 12% of beryllium-exposed American workers would test positive on beryllium lymphocyte proliferation test (BeLPT screening, but the implications of sensitization remain uncertain. Methods Seventy two current and former employees of a beryllium manufacturer, including 22 with pathologic changes of chronic beryllium disease (CBD, and 50 without, with a confirmed positive test were followed-up for 7.4 +/-3.1 years. Results Beyond predicted effects of aging, flow rates and lung volumes changed little from baseline, while DLCO dropped 17.4% of predicted on average. Despite this group decline, only 8 subjects (11.1% demonstrated physiologic or radiologic abnormalities typical of CBD. Other than baseline status, no clinical or laboratory feature distinguished those who clinically manifested CBD at follow-up from those who did not. Conclusions The clinical outlook remains favorable for beryllium-sensitized individuals over the first 5-12 years. However, declines in DLCO may presage further and more serious clinical manifestations in the future. These conclusions are tempered by the possibility of selection bias and other study limitations.

  19. Parametric studies of carbon erosion mitigation dynamics in beryllium seeded deuterium plasmas

    International Nuclear Information System (INIS)

    The characteristic time of protective beryllium layer formation on a graphite target, τBe/C, has been investigated as a function of surface temperature, Ts, ion energy, Ei, ion flux, Γi, and beryllium ion concentration, cBe, in beryllium seeded deuterium plasma. τBe/C is found to be strongly decreased with increasing Ts in the range of 550-970K. This is thought to be associated with the more efficient formation of beryllium carbide (Be2C). By scanning the parameters, a scaling expression for τBe/C has been derived as τBe/C[s]=1.0x10-7cBe-1.9+/-0.1Ei0.9+/-0.3Γi-0.6+/-0.3exp ((4.8+/-0.5)x103/Ts) where cBe is dimensionless, Ei in eV, Γi in 1022m-2s-1 and Ts in K. Should this scaling extend to an ITER scenario, carbon erosion of the divertor strike point region may be reduced with characteristic time of ∼6ms. This is much shorter than the time between predicted ITER type I ELMs (∼1s), and suggests that protective beryllium layers can be formed in between ELMs, and mitigate carbon erosion.

  20. Summary of Surface Swipe Sampling for Beryllium on Lead Bricks and Shielding

    International Nuclear Information System (INIS)

    Approximately 25,000 lbs of lead bricks at Site 300 were assessed by the Site 300 Industrial Hygienis tand Health Physicist for potential contamination of beryllium and radiation for reuse. These lead bricks and shielding had been used as shielding material during explosives tests that included beryllium and depleted uranium. Based on surface swipe sampling that was performed between July 26 and October 11, 2010, specifically for beryllium, the use of a spray encapsulant was found to be an effective means to limit removable surface contamination to levels below the DOE release limit for beryllium, which is 0.2 mcg/100 cm2. All the surface swipe sampling data for beryllium and a timeline of when the samples were collected (and a brief description) are presented in this report. On December 15, 2010, the lead bricks and shielding were surveyed with an ion chamber and indicated dose rates less than 0.05 mrem per hour on contact. This represents a dose rate consistent with natural background. An additional suevey was performed on February 8, 2011, using a GM survey instrument to estimate total activity on the lead bricks and shielding, confirming safe levels of radioactivity. The vendor is licensed to possess and work with radioactive material.

  1. Beryllium. Health hazards and their control. Pt. 2

    International Nuclear Information System (INIS)

    In this work (continuation of 'Beryllium' series) health hazards, toxic effects, limits of permissible atmospheric contamination and safe exposure to beryllium are described. Guidelines to the design, control operations and hygienic precautions of the working facilities are given. (Author)

  2. Mechanical performance of irradiated beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Dalle-Donne, M.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reaktortechnik

    1998-01-01

    For the Helium Cooled Pebble Bed (HCPB) Blanket, which is one of the two reference concepts studied within the European Fusion Technology Programme, the neutron multiplier consists of a mixed bed of about 2 and 0.1-0.2 mm diameter beryllium pebbles. Beryllium has no structural function in the blanket, however microstructural and mechanical properties are important, as they might influence the material behavior under neutron irradiation. The EXOTIC-7 as well as the `Beryllium` experiments carried out in the HFR reactor in Petten are considered as the most detailed and significant tests for investigating it. This paper reviews the present status of beryllium post-irradiation examinations performed at the Forschungszentrum Karlsruhe with samples from these irradiation experiments, emphasizing the effects of irradiation of essential material properties and trying to elucidate the processes controlling the property changes. The microstructure, the porosity distribution, the impurity content, the behavior under compression loads and the compatibility of the beryllium pebbles with lithium orthosilicate (Li{sub 4}SiO{sub 4}) during the in-pile irradiation are presented and critically discussed. Qualitative information on ductility and creep obtained by hardness-type measurements are also supplied. (author)

  3. The isolation of beryllium and mercury from lithium chloride solution by means of gas extraction

    International Nuclear Information System (INIS)

    The possibility and optimal conditions of beryllium and mercury extraction using acetylacetone (HAA) from lithium chloride solution by argon blowing through the solution are determined. Dependences of extraction degrees and distribution coefficients on different parameters of liquid phase: initial pH value, lithium chloride concentration and initial content of HAA, are presented. The degree of beryllium extraction reaches the maximum at liquid phase pH of 4.4-5.25 and concentration of lithium chloride of 8.5 mol/l. Distribution coefficient changes in inverse proportion to the extraction degree

  4. Micromechanical properties of beryllium and other instrument materials, end-of-year-report

    International Nuclear Information System (INIS)

    The objective of the program is to evaluate and understand the micromechanical properties of beryllium and other instrument materials for use in gyroscopes, so that dimensional instability can be improved. Improved dimensional stability is expected to lessen the need to periodically align gyroscopes in service. Drift in alignment has been attributed in part to mass shifts of 0.000001 inches in critical components of gyroscopes. This report consists of two major parts. Part A - Micromechanical properties of instrument grade beryllium. (description of the materials problem, instrumentation to make strain measurements in the range of 10 to the -7 power, and initial results.) Part B - 10 to the -8 power creep measurement system

  5. Isothermal compression and phase transition in beryllium to 28.3 GPa

    International Nuclear Information System (INIS)

    In situ high-pressure x-ray diffraction data for polycrystalline beryllium to 28.3 GPa at ambient temperature show that beryllium is transformed from the HCP phase (I) into a slightly distorted HCP phase (II) at pressures between 8.6 and 14.5 GPa. The volume change for the transition is extremely small (approx. 0.4%); the effect of pressure on the c/a ratio for both the Be(I) and Be(II) phases is also very small. (author)

  6. Leachability characteristics of beryllium in redmud waste and its stabilization in cement

    International Nuclear Information System (INIS)

    More than 70% of the beryl ore processed by the Beryllium Metal Plant at the BARC Vashi Complex ends up as redmud waste. The presence of significant quantities (0.4 to 0.8%) of beryllium in the redmud qualifies it as hazardous requiring safe handling, storage and disposal. The waste also contains 0.09% of water soluble fluoride. The various standard protocol of procedures were employed to estimate the leachability of beryllium from redmud for both short term and long term periods. Nearly 50% of beryllium present in redmud is leachable in water. We have tried the stabilization of redmud using portland cement. The proportion of redmud to cement was in the ratio of 1:1, 1:2 and 1:4. The blocks were cast, cured and used in the leachability experiments using standard protocols as above. The results of the TCLP test gave the levels of beryllium well below the standard limits in the TCLP extract of cement stabilized waste indicating the suitability of stabilization of redmud with cement whereas that of raw waste (redmud) are much higher than the prescribed limits. The total leach percent of beryllium in 1:2 block is 0.05% over period of 164 days whereas 1:1 and 1:4 gave a leach percent of 0.26 and 0.15% respectively. The DLT results indicate, diffusion controlled release of beryllium from the cement stabilized redmud blocks. The effective diffusion coefficient of beryllium obtained from the modelling study is 10 orders of magnitude less than the molecular diffusion coefficient of beryllium indicating the effectiveness of cement stabilization. From the detailed experiments performed, it is felt that 1:2 proportion of redmud and cement will be the best suited option for stabilization of redmud waste. The 1:1 proportion of redmud to cement mixture which could not be cast into compact cement blocks also exhibited very low leachability characteristics similar to 1:2 and 1:4 and can be be favourably considered for stabilization in case of space constraints at storage sites. The

  7. Neutron emission from the strongly damped reaction 165Ho + 56Fe at 8.5 MeV

    International Nuclear Information System (INIS)

    Neutron and α-particle emission from the 165Ho + 56Fe reaction at 8.5 MeV/A has been studied for damped and fusion-fission events. It is shown, that the measured multiplicities, energy spectra and angular distributions of neutrons are consistent with a full equilibration of the excitation energy and the N/Z degree of freedom during the reaction time. (orig.)

  8. 75 FR 80734 - Chronic Beryllium Disease Prevention Program

    Science.gov (United States)

    2010-12-23

    ... Beryllium Disease Prevention Program (CBDPP) (63 FR 66940). After considering the comments received, DOE... CFR Part 850 RIN 1992-AA39 Chronic Beryllium Disease Prevention Program AGENCY: Office of Health... beryllium disease prevention program. The Department solicits comment and information on the...

  9. Spectrographic determination of impurities in beryllium oxide

    International Nuclear Information System (INIS)

    A method for the spectrographic determination of Al, B, Cd, Co, Cu, Cr, Fe, Mg, NaNi, Si and Zn in nuclear grade beryllium oxide has been developed. The determination of Co, Al, Na and Zn is besed upon a carrier distillation technique. Better results were obtained with 2% Ga2O3 as carrier in beryllium oxide. For the elements B, Cd, Cu, Fe, Cr, Mg, Ni and Si the sample is loaded in a Scribner-Mullin shallow cup electrode, covered with graphite powder and excited in DC arc. The relative standard deviation values for different elements are in the range of 10 to 20%. The method fulfills requirements of precision and sensitivity for specification analysis of nuclear grade beryllium oxide.(Author)

  10. Remarkable Hydrogen Storage on Beryllium Oxide Clusters: First Principles Calculations

    CERN Document Server

    Shinde, Ravindra

    2016-01-01

    Since the current transportation sector is the largest consumer of oil, and subsequently responsible for major air pollutants, it is inevitable to use alternative renewable sources of energies for vehicular applications. The hydrogen energy seems to be a promising candidate. To explore the possibility of achieving a solid-state high-capacity storage of hydrogen for onboard applications, we have performed first principles density functional theoretical calculations of hydrogen storage properties of beryllium oxide clusters (BeO)$_{n}$ (n=2 -- 8). We observed that polar BeO bond is responsible for H$_{2}$ adsorption. The problem of cohesion of beryllium atoms does not arise, as they are an integral part of BeO clusters. The (BeO)$_{n}$ (n=2 -- 8) adsorbs 8--12 H$_{2}$ molecules with an adsorption energy in the desirable range of reversible hydrogen storage. The gravimetric density of H$_{2}$ adsorbed on BeO clusters meets the ultimate 7.5 wt% limit, recommended for onboard practical applications. In conclusion,...

  11. 2013 INORGANIC REACTION MECHANISMS GORDON RESEARCH CONFERENCE (MARCH 3-8, 2013 - HOTEL GALVEZ, GALVESTON TX)

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Omar, Mahdi M.

    2012-12-08

    The 2013 Gordon Conference on Inorganic Reaction Mechanisms will present cutting-edge research on the molecular aspects of inorganic reactions involving elements from throughout the periodic table and state-of-the art techniques that are used in the elucidation of reaction mechanisms. The Conference will feature a wide range of topics, such as homogeneous and heterogeneous catalysis, metallobiochemistry, electron-transfer in energy reactions, polymerization, nitrogen fixation, green chemistry, oxidation, solar conversion, alkane functionalization, organotransition metal chemistry, and computational chemistry. The talks will cover themes of current interest including energy, materials, and bioinorganic chemistry. Sections cover: Electron-Transfer in Energy Reactions; Catalytic Polymerization and Oxidation Chemistry; Kinetics and Spectroscopy of Heterogeneous Catalysts; Metal-Organic Chemistry and its Application in Synthesis; Green Energy Conversion;Organometallic Chemistry and Activation of Small Molecules; Advances in Kinetics Modeling and Green Chemistry; Metals in Biology and Disease; Frontiers in Catalytic Bond Activation and Cleavage.

  12. Low-temperature solubility of copper in beryllium, in beryllium--aluminum, and in beryllium--silicon using ion beam

    International Nuclear Information System (INIS)

    Ion implantation and ion backscattering analysis have been used to measure the solubility of copper in beryllium over the temperature range 593 to 1023 K, and to determine the effect on the copper solubility of aluminum and silicon impurities. The binary data extend 280 K lower in temperature than previous results, while the ternary measurements are unique. The information is pertinent to the use of copper for solution strengthening of beryllium. Diffusion couples were formed by ion implantation of copper into single-crystal beryllium at room temperature, followed where appropriate by implantation of aluminum or silicon. The samples were then annealed isothermally, and the time-evolution of the composition-vs-depth profile, determined by ion backscattering analysis, yielded the solubility of copper. Measurements at exceptionally low temperatures were facilitated by the short diffusion distances, approximately equal to 0.1 mu m, and the use of neon irradiation to accelerate diffusion. The resulting binary data for the solubility C0 of copper in beryllium merge smoothly into previous results at higher temperatures. The combined data, covering the temperature range 593 to 1373 K, are well described by C0 = (12.6 at. pct) . exp (-842 K/T). In the ternary regime, the effects of aluminum and silicon on the solubility of copper were found to be small

  13. Preliminary results for explosion bonding of beryllium to copper

    Energy Technology Data Exchange (ETDEWEB)

    Butler, D.J. [Northwest Technical Industries, Inc., Sequim, WA (United States); Dombrowski, D.E. [Brush Wellman, Inc., Cleveland, OH (United States)

    1995-09-01

    This program was undertaken to determine if explosive bonding is a viable technique for joining beryllium to copper substrates. The effort was a cursory attempt at trying to solve some of the problems associated with explosive bonding beryllium and should not be considered a comprehensive research effort. There are two issues that this program addressed. Can beryllium be explosive bonded to copper substrates and can the bonding take place without shattering the beryllium? Thirteen different explosive bonding iterations were completed using various thicknesses of beryllium that were manufactured with three different techniques.

  14. Beryllium Abundances in Solar Mass Stars

    Science.gov (United States)

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

    2008-08-01

    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 3.5×106 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.

  15. An angular momentum selection rule and the 9Be(π+,p)8Be reaction at 50 MeV

    International Nuclear Information System (INIS)

    Angular distributions have been measured at 50 MeV for the 9Be(π+,p)8Be reaction leading to the 0+, 2+ and 4+ states of 8Be. An angular momentum selection rule is considered in order to account for the preferential excitation of high spin states. Two-step processes in the framework of the DWBA and momentum sharing in the two-nucleon model are also discussed

  16. Fragment charge and energy distributions in the 1.8-4.8 GeV {sup 3}He + {sup nat}Ag, {sup 197}Au reactions

    Energy Technology Data Exchange (ETDEWEB)

    Bracken, D.S.; Foxford, E.R.; Kwiatkowski, K. [and others

    1995-10-01

    Moving source fits have been performed for IMFs as a function of observables related to collision violence in the 1.8-4.8 GeV {sup 3}He +{sup nat}Ag, {sup l97}Au reactions. The systematic behavior of the source properties and fragment charge distributions will be reviewed. The evolution of the spectral Coulomb parameters provides evidence for nuclear expansion prior to multifragmentation, suggesting a breakup density of p/p{sub o} {approximately} 1/3. The charge distributions will be examined in terms of power-law fits and moment analyses.

  17. Fragment charge and energy distributions in the 1.8-4.8 GeV 3He + natAg, 197Au reactions

    International Nuclear Information System (INIS)

    Moving source fits have been performed for IMFs as a function of observables related to collision violence in the 1.8-4.8 GeV 3He +natAg, l97Au reactions. The systematic behavior of the source properties and fragment charge distributions will be reviewed. The evolution of the spectral Coulomb parameters provides evidence for nuclear expansion prior to multifragmentation, suggesting a breakup density of p/po ∼ 1/3. The charge distributions will be examined in terms of power-law fits and moment analyses

  18. Experimental Cross Sections for Reactions of Heavy Ions and sup 2 sup 0 sup 8 Pb, sup 2 sup 0 sup 9 Bi, sup 2 sup 3 sup 8 U, and sup 2 sup 4 sup 8 Cm Targets

    CERN Document Server

    Patin, J B

    2002-01-01

    The study of the reactions between heavy ions and sup 2 sup 0 sup 8 Pb, sup 2 sup 0 sup 9 Bi, sup 2 sup 3 sup 8 U, and sup 2 sup 4 sup 8 Cm targets was performed to look at the differences between the cross sections of hot and cold fusion reactions. Experimental cross sections were compared with predictions from statistical computer codes to evaluate the effectiveness of the computer code in predicting production cross sections. Hot fusion reactions were studied with the MG system, catcher foil techniques and the Berkeley Gas-filled Separator (BGS). 3n- and 4n-exit channel production cross sections were obtained for the sup 2 sup 3 sup 8 U( sup 1 sup 8 O,xn) sup 2 sup 5 sup 6 sup - sup x Fm, sup 2 sup 3 sup 8 U( sup 2 sup 2 Ne,xn) sup 2 sup 6 sup 0 sup - sup x No, and sup 2 sup 4 sup 8 Cm( sup 1 sup 5 N,xn) sup 2 sup 6 sup 3 sup - sup x Lr reactions and are similar to previous experimental results. The experimental cross sections were accurately modeled by the predictions of the HIVAP code using the Reisdorf ...

  19. Quantitative differential thermal analysis study of the U/sub 3/O/sub 8/-Al thermite reaction

    International Nuclear Information System (INIS)

    Concerns about proliferation resistance of nuclear fuels and fuel cycles have prompted a reinvestigation of U/sub 3/O/sub 8/-Al cermet fuels currently being used in research and test reactors. In particular, higher loadings of U/sub 3/O/sub 8/ are being considered. These new fuel compositions are in the region of maximum possible thermal energy release from the high temperature thermite reaction between the U/sub 3/O/sub 8/ and aluminum components. The present study was initiated to measure the amount of reaction heat evolved quantitatively. A differential thermal analysis system was calibrated with materials of known heats of reaction. Subsequently, specimens of high uranium-load U/sub 3/O/sub 8/-Al powder mixtures were analyzed. Preliminary results showed that the thermite reaction heat evolved from these specimens was much lower than expected. Specimens of simulated fuel plates showed similar low results. Possible reasons for this behavior are discussed. 18 refs

  20. Radiative capture reaction {sup 7}Be(p,{gamma}){sup 8}B in the continuum shell model

    Energy Technology Data Exchange (ETDEWEB)

    Bennaceur, K.; Ploszajczak, M. [Grand Accelerateur National d`Ions Lourds (GANIL), Caen (France); Nowacki, F. [Grand Accelerateur National d`Ions Lourds (GANIL), Caen (France)]|[Lab. de Physique Theorique Strasbourg, Strasbourg (France); Okolowicz, J. [Grand Accelerateur National d`Ions Lourds (GANIL), Caen (France)]|[Inst. of Nuclear Physics, Krakow (Poland)

    1998-06-01

    We present here the first application of realistic shell model (SM) including coupling between many-particle (quasi-)bound states and the continuum of one-particle scattering states to the calculation of the total capture cross section and the astrophysical factor in the reaction {sup 7}Be(p,{gamma}){sup 8}B. (orig.)

  1. Nuclear reactions and electromagnetic dissociation of 8Li, 9Li, 11Li at 100 MeV/n

    International Nuclear Information System (INIS)

    Measurements of nuclear reaction and electromagnetic dissociation cross-sections have been performed at SATURNE with secondary beams of 8Li, 9Li, 11Li interacting with C, Al, Cu, Sn, Pb targets at energies around 100 MeV/n. The detection method relies on beta-decay characteristics, energy-loss, total energy and range measurements

  2. Trace determination of sulfur and beryllium by activation in an oxygen-18 ion beam

    International Nuclear Information System (INIS)

    A novel method for determining traces of sulfur and beryllium is described. The reaction 32S(18O,t)47V is selective if using a 39 MeV 18O6+ beam. The detection limit is 3 ppm in an iron matrix and a precision of +-15% has been achieved for samples with 15 to 20 ppm sulfur. In the case of beryllium determination, two reactions were studied, namely 9Be(18O,2α)19O and 9Be(18O,d)25Na. At 25 MeV 18O5+, the first reaction is completely selective and yields a 5 ng detection limit for a 5 minutes irradiation. Boron is a nuclear interference when using the second reaction which yields a 110 ng detection limit in the same conditions. An irradiation chamber has been constructed that allows to decrease these limits. The technique was tested by analyzing two standard materials (NBS-SRM 394 and IRSID 508-1) whose sulfur content is certified. The results obtained by analyzing a biological sample (NBS-SRM 1571) for sulfur and a metallic sample Cu-Be for beryllium, are discussed

  3. Potential exposures and risks from beryllium-containing products.

    Science.gov (United States)

    Willis, Henry H; Florig, H Keith

    2002-10-01

    Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern. PMID:12442995

  4. Magnesium Cermets and Magnesium-Beryllium Alloys

    International Nuclear Information System (INIS)

    The paper describes some results of work on the development of magnesium-magnesium oxide cermets and of super heat-resistant magnesiumberyllium alloys produced by powder metallurgical methods. The introduction of even a minute quantity of finely dispersed magnesium oxide into magnesium results in a strengthening of the material, the degree of which increases with increased magnesium oxide concentration, although variation of this concentration within the limits of 0.3 to 5 wt.% has a comparatively slight effect on the corresponding variation in the short-term strength over the whole range of temperatures investigated. At 20oC, in the case of the cermets, σβ = 28 to 31 kg/mm2 and δ = 3 .5 to 4.5%; at 500oC σβ = 2.6 to 3.2 kg/mm2 and δ =30 to 40%. The positive effect of the finely dispersed oxide phase is particularly evident in protracted tests. For magnesium cermets, σ (300)/100 = 2.2 kg/mm2. Characteristic of the mixtures is the high thermal stability of the strength properties, linked chiefly with the thermodynamic stability of the strength-giving oxide phase in the metal matrix. The use of powder metallurgical methods has yielded super heat-resistant magnesium-beryllium alloys containing heightened concentrations of beryllium (PMB alloys). In their strength characteristics PMB alloys are close to Mg-MgO cermets, but the magnesium-beryllium alloys have a degree and duration of resistance to high temperature oxidation which exceeds the corresponding qualities of the magnesium alloys at present known. Thus, in air of 580oC, PMB alloys with 2 to 5% beryllium maintain a high resistance to oxidation for a period of over 12000 to 14000 h. This long-term heat resistance is chiefly a result of the amount of beryllium in the alloy, and increases with increasing beryllium content. PMB alloys are also marked by high resistance to short bursts of overheating. Magnesium cermets and magnesium-beryllium alloys, with their enhanced high-temperature stability, are capable

  5. Portable Beryllium Prospecting Instrument With Large Sensitive Area

    International Nuclear Information System (INIS)

    The instrument described was designed on the basis of the photoneutron method of determining beryllium in rock surfaces and developed with a view to prospecting beryllium minerals in the Ilímaussaq intrusion, south Greenland. These minerals occur,mainly in hydrothermal veins which are from 1 mm to about 2 m wide. Of the ten beryllium minerals found until now, chkalovite (12% BeO) is the most common. The distinctive feature of the prospecting instrument is a comparatively large effective measuring area (∼500 cm2). Since the instrument is intended for use in a difficult terrain without roads, it has been necessary to limit its weight and size as much as possible. The instrument consists of a detector unit and a control unit. The detector unit has the dimensions 46 x 21 x 10 cm, weighs 20 kg, and contains a 30 cm long gamma-activation device, a biological radiation shield, and two 30-cm long 3He-filled neutron proportional detectors embedded in paraffin wax. The gamma- activation device consists of 31 identical 12Sb-sources placed in a steel tube with spacings decreasing towards the ends of the tube and with a total activity of 20 mCi. During transport of the instrument the gamma-activation device is placed at the centre of the radiation shield, when the maximum dose-rate on the surface of the detector unit is 200 mR/h. When the instrument is in use, the activation device is turned to a position just above the bottom of the detector unit. The sensitivity per cm2 of the bottom surface to a 5-cm thick layer of beryllium is 20% of its value at the centre of the bottom surface along a curve which is roughly an ellipse with axes 34 and 18 cm The total sensitivity of the instrument is about 35 counts/min per % BeO per mCi 124Sb, and the background count-rate is 12-20 counts/mm. The corresponding theoretical detection limit for a single measurement of 8-min duration is 35-50 ppm BeO. (author)

  6. Status of beryllium development for fusion applications

    International Nuclear Information System (INIS)

    Beryllium is a leading candidate material for the neutron multiplier of tritium breeding blankets and the plasma-facing component of first-wall and divertor systems. Depending on the application, the fabrication methods proposed include hot-pressing, hot-isostatic-pressing, cold-isostatic-pressing/sintering, rotary electrode processing and plasma spraying. Product forms include blocks, tubes, pebbles, tiles and coatings. While, in general, beryllium is not a leading structural material candidate, its mechanical performance, as well as its performance with regard to sputtering, heat transport, tritium retention/release, helium-induced swelling and chemical compatibility, is an important consideration in first-wall/blanket design. Differential expansion within the beryllium causes internal stresses which may result in cracking, thereby affecting the heat transport and barrier performance of the material. Overall deformation can result in loading of neighboring structural material. Thus, in assessing the performance of beryllium for fusion applications, it is important to have a good database in all of these performance areas, as well as a set of properties correlations and models for the purpose of interpolation/extrapolation.In this current work, the range of anticipated fusion operating conditions is reviewed. The thermal, mechanical, chemical compatibility, tritium retention/release, and helium retention/swelling databases are then reviewed for fabrication methods and fusion operating conditions of interest. Properties correlations and uncertainty ranges are also discussed. In the case of the more complex phenomena of tritium retention/release and helium-induced swelling, fundamental mechanisms and models are reviewed in more detail. Areas in which additional data are needed are highlighted, along with some trends which suggest ways of optimizing the performance of beryllium for fusion applications. (orig.)

  7. Study of the U/sub 3/O/sub 8/-Al thermite reaction and strength of reactor fuel tubes

    Energy Technology Data Exchange (ETDEWEB)

    Peacock, H.B.

    1983-08-01

    Heating tests using 53 wt % U/sub 3/O/sub 8/-Al pellets show that an exothermic reaction occurs between 875 and 1000/sup 0/C and takes 10 to 20 seconds to reach maximum temperature. The maximum temperature is a function of particle size of the U/sub 3/O/sub 8/ with large particles exhibiting lower peak temperatures. The calculated energy release was 123 cal/g of U/sub 3/O/sub 8/-aluminum fuel. Tests using aluminum clad outer fuel tube sections gave lower peak temperatures than for pellets. No violent reactions occurred. The results are reasonably consistent with recent reported data indicating that the exothermic U/sub 3/O/sub 8/-Al reaction is not an important energy source. The compressive and tensile strengths of U/sub 3/O/sub 8/ tubes above 660/sup 0/C are low. In compression, sections with 2 psi average axial stress failed at 917/sup 0/C, while sections with 7 psi failed at 669/sup 0/C. Tubes with U-Al alloy cores failed at about 670/sup 0/C with no applied load. The stresses in fuel tubes during a reactor transient may range up to several hundred psi and are less than 7 psi only in the upper part of the fuel tube.

  8. Metallic beryllium-7 target of small diameter

    CERN Document Server

    Zyuzin, A Yu; Vincent, J S; Buckley, K R; Bateman, N P; Snover, K A; Csandjan, J M; Steiger, T D; Adelberger, E G; Swanson, H E

    1999-01-01

    The stellar sup 7 Be(p, gamma) sup 8 B reaction rate has the largest uncertainty among all nuclear reaction rates in the standard solar model. However, the solar neutrino flux predicted for the majority of proposed and existing solar neutrino detectors is directly dependent on the rate of sup 7 Be(p, gamma) sup 8 B reaction. The existing solar neutrino detectors measure rate of sup 8 B decay neutrinos that is too low. This constitutes largely the solar neutrino problem. Existing measurements of the sup 7 Be(p, gamma) sup 8 B reaction rate disagree with one another, indicating the need for more precise experiments. To provide the required targets a new procedure for sup 7 Be production, separation and target manufacturing has been developed. First, a lithium target has been designed for sup 7 Be production at TRIUMF's 13 MeV cyclotron. The lithium target has been extensively tested at 50 mu A proton beam current yielding 8.1 MBq/mu A h of sup 7 Be. An adsorption filtration technique has been developed for sup ...

  9. 4π studies of the 1.8-4.8 GeV 3He+natAg, 197Au reactions. I. Energy deposition

    International Nuclear Information System (INIS)

    The 4π detector ISiS has been used to measure light-charged particles and intermediate-mass-fragments emitted in the 1.8-4.8 GeV 3He+natAg, 197Au reactions. Ejectile multiplicity and total event kinetic energy distribution scale systematically with projectile energy and target mass, except for the natAg target at 3.6 and 4.8 GeV. For this system, a saturation in deposition energy is indicated by the data, suggesting the upper projectile energy for stopping has been reached. Maximum deposition energies of ∼950 MeV for the natAg target and ∼1600 MeV for the 197Au target are inferred from the data. Comparison of the experimental distributions with intranuclear cascade predictions shows qualitative agreement. (author)

  10. 4{pi} studies of the 1.8-4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. I. Energy deposition

    Energy Technology Data Exchange (ETDEWEB)

    Morley, K.B.; Kwiatkowski, K.; Bracken, D.S.; Renshaw Foxford, E. [Indiana Univ., Bloomington, IN (United States). Dept. of Chemistry; Legrain, R.; Pollacco, E.C.; Volant, C. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Korteling, R.G. [Simon Fraser Univ., Burnaby, BC (Canada). Dept. of Chemistry; Breuer, H. [Maryland Univ., College Park, MD (United States). Dept. of Physics; Brzychczyk, J. [Jagellonian Univ., Krakow (Poland). Inst. of Physics

    1996-01-01

    The 4{pi} detector ISiS has been used to measure light-charged particles and intermediate-mass-fragments emitted in the 1.8-4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. Ejectile multiplicity and total event kinetic energy distribution scale systematically with projectile energy and target mass, except for the {sup nat}Ag target at 3.6 and 4.8 GeV. For this system, a saturation in deposition energy is indicated by the data, suggesting the upper projectile energy for stopping has been reached. Maximum deposition energies of {approx}950 MeV for the {sup nat}Ag target and {approx}1600 MeV for the {sup 197}Au target are inferred from the data. Comparison of the experimental distributions with intranuclear cascade predictions shows qualitative agreement. (author). Submitted to Physical Review, C (US); 46 refs.

  11. Development of beryllium bonds for plasma-facing components

    International Nuclear Information System (INIS)

    This study concerns the techniques of bonding beryllium to both structural material (AISI 316 SS) and heat sink material (copper and DS-copper) plates, and the characterization of the bonding material obtained. Conventional bonding techniques for joining Be to SS and copper using brazing alloys were first investigated. The best result was obtained using a silver-copper eutetic alloy as a brazing alloy. However, the high-temperature capability of the materials prepared by this method is limited by the performance of brazing alloys at the operating temperature. To avoid this problem, we are developing a joining process known as solid-state reaction bonding that improves the capability at the operating temperature. (orig.)

  12. Electron microscope observation of single - crystalline beryllium thin foils

    International Nuclear Information System (INIS)

    Thin foils prepared from single crystalline beryllium simples deformed at room temperature, have been observed by transmission electron microscopy. The various deformation modes have been investigated separately, from their early stages and their characteristic dislocation configurations have been observed. Basal slip is characterized at is outset by the presence of numerous dipoles and elongated prismatic loops. More pronounced cold work leads to the formation of dislocation tangles and bundles which eventually give a cellular structure. Prismatic slip begins by the cross-slip of dislocations from the basal plane into the prismatic plane. A cellular structure is equally observed in heavily deformed samples. Sessile dislocations have been observed in twin boundaries; they are produced by reactions between slip dislocations and twin dislocations. Finally, the study of samples quenched from 1100 deg. C and annealed at 200 deg. C has shown that the observed loops lie in prismatic planes and have a Burgers vector b 1/3. (authors)

  13. A non-chemical spectroscopic determination of atmospheric beryllium

    International Nuclear Information System (INIS)

    Beryllium in the atmosphere is determined by emission spectroscopy using a non-chemical method of analysis. Long term effects of beryllium poisoning result in respiratory and skin disease, and this is partly reflected by the low threshold limits (0.002 mg/m3). In comparison the threshhold values for lead and cadmium are 0.2 and 0.16 mg/m3 respectively. Air samples are collected at 2 litres/ minute using cellulose filters, and sampling time is dependent on the individual process being monitored, but can be as short as five minutes, eg. dental laboratories. The filters are initially divided in two parts, and one portion is carefully pelletised using a steel press. The pellet is placed in an electrode cup and 'wetted' using isopropanol and ethylene glycol. Wetting is necessary because the pellets tended to explode out of the arcing zone. Calibration graphs were produced using an internal cobalt standard, and the 234.8 nm, 313.0 nm emission lines were used. No spectral and inter-element effects were observed, and the minimum detection limit was one nanogram. Under normal working conditions a 25% precision was obtained. (author)

  14. Safety handling of beryllium for fusion technology R and D

    International Nuclear Information System (INIS)

    Feasibility of beryllium use as a blanket neutron multiplier, first wall and plasma facing material has been studied for the D-T burning experiment reactors such as ITER. Various experimental work of beryllium and its compounds will be performed under the conditions of high temperature and high energy particle exposure simulating fusion reactor conditions. Beryllium is known as a hazardous substance and its handling has been carefully controlled by various health and safe guidances and/or regulations in many countries. Japanese regulations for hazardous substance provide various guidelines on beryllium for the protection of industrial workers and environment. This report was prepared for the safe handling of beryllium in a laboratory scale experiments for fusion technology R and D such as blanket development. Major items in this report are; (1) Brief review of guidances and regulations in USA, UK and Japan. (2) Safe handling and administration manuals at beryllium facilities in INEL, LANL and JET. (3) Conceptual design study of beryllium handling facility for small to mid-scale blanket R and D. (4) Data on beryllium toxicity, example of clinical diagnosis of beryllium disease, and environmental occurence of beryllium. (5) Personnel protection tools of Japanese Industrial Standard for hazardous substance. (author) 61 refs

  15. Control of beryllium powder at a DOE facility

    International Nuclear Information System (INIS)

    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

  16. Study of the U/sub 3/O/sub 8/-Al thermite reaction and strength of reactor fuel tubes

    Energy Technology Data Exchange (ETDEWEB)

    Peacock, H B

    1983-01-01

    Research and test reactors are presently operated with aluminum-clad fuel elements containing highly enriched uranium-aluminum alloy cores. To lower the enrichment and still maintain reactivity, the uranium content of the fuel element will need to be higher than currently achievable with alloy fuels. This will necessitate conversion to other forms such as U/sub 3/O/sub 8/-aluminum cermets. Above the aluminum melting point, U/sub 3/O/sub 8/ and aluminum undergo an exothermic thermite reaction and cermet fuel cores tend to keep their original shape. Both factors could affect the course and consequences of a reactor accident, and prompted an investigation of the behavior of cermet fuels at elevated temperatures. Tests were carried out using pellets and extruded tube-sections with 53 wt % U/sub 3/O/sub 8/ in aluminum. This content corresponds to a theoretical uranium density of 1.9 g/cc. Results indicate that the thermite reaction occurs at about 900/sup 0/C in air without a violent effect. The heat of reaction was approximately 123 cal/g of U/sub 3/O/sub 8/-aluminum fuel. Tensile and compressive strength of the fuel tube section is low above 660/sup 0/C. In tension, sections failed at about the aluminum melting point. In compression with 2-psi average axial stress, failure occurred at 917/sup 0/C, while 7 psi average axial stress produced failure at 669/sup 0/C.

  17. Electrochemical properties of submicron-sized LiV3O8 synthesized by a low-temperature reaction route

    International Nuclear Information System (INIS)

    Submicron-sized LiV3O8 cathode materials were synthesized using a low-temperature reaction route with the help of grinding and the following calcination. A mixture of Li(ac).2H2O(ac = acetate), NH4VO3 and excess H2C2O4.2H2O was used as starting material without any solvent. Characterization results of X-ray diffraction (XRD), scanning electron microscopy (SEM), charge-discharge test, and cyclic voltammogram (CV) indicated that the sample heat-treated at 350 deg. C shows the best electrochemical performance. This low-temperature reaction route is a simple but efficient synthesis route for preparing high-performance LiV3O8 cathode material

  18. The credit analysis of recycling beryllium and uranium in BeO-UO2 nuclear fuel

    International Nuclear Information System (INIS)

    This study quantifies the credits of beryllium and uranium which are used as the raw materials for BeO-UO2 nuclear fuel by analyzing the influence of their credits on the nuclear fuel cycle cost was analyzed, where the credit was defined as the value of raw materials recovered from spent fuel and the raw materials that were re-cycled. The credits of beryllium and uranium at 60 MWD/kg burn-up were -0.22 Mills/kWh and -0.14 Mills/kWh, respectively. These findings were based on the assumption that the optimal mixing proportion of beryllium in the BeO-UO2 nuclear fuel is 4.8 wt%. In sum, the present study verified that the credits of beryllium and uranium in relation to BeO-UO2 nuclear fuel are significant cost drivers in the cost of the nuclear fuel cycle and in estimating the nuclear fuel cycle of the reprocessing option for spent nuclear fuels. (author)

  19. 8+, 10+ and 9- states excited by the reactions (p, t) and (p, p') on even-even tin isotopes

    International Nuclear Information System (INIS)

    In order to find the 8+, 10+ (h sub(11/2))2 9- (h sub(11/2), g sub(7/2)) states the reactions (p, t) and (p, p') on even tin isotopes at a bombarding energy of 54.9 MeV have been investigated with RCNP isochronous cyclotron and a high-resolution magnetic spectrograph ''RAIDEN''. The experimental angular distributions were analyzed by DWBA calculations, and the lowest 6+, 8+, 10+ and 9- states in sup(114 -- 124)Sn were established. (author)

  20. Inherent Stereospecificity in the Reaction of Aflatoxin B1 8,9-Epoxide with Deoxyguanosine and Efficiency of DNA Catalysis

    OpenAIRE

    Brown, Kyle L.; Bren, Urban; Stone, Michael P.; Guengerich, F. Peter

    2009-01-01

    Kinetic analysis of guanine alkylation by aflatoxin B1 exo-8,9-epoxide, the reactive form of the hepatocarcinogen aflatoxin B1, reveals the reaction to be > 2000-times more efficient in DNA than in aqueous solution, i.e. with free 2’-deoxyguanosine. Thermodynamic analysis reveals AFB1 exo-8,9-epoxide intercalation as the predominant source of the observed DNA catalytic effect. However, the known exo > endo epoxide stereospecificity of the DNA alkylation is observed even with free deoxyguanosi...

  1. Study on neutron irradiation behavior of beryllium as neutron multiplier

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1998-03-01

    More than 300 tons beryllium is expected to be used as a neutron multiplier in ITER, and study on the neutron irradiation behavior of beryllium as the neutron multiplier with Japan Materials Testing Reactor (JMTR) were performed to get the engineering data for fusion blanket design. This study started as the study on the tritium behavior in beryllium neutron reflector in order to make clear the generation mechanism on tritium of JMTR primary coolant since 1985. These experiences were handed over to beryllium studies for fusion study, and overall studies such as production technology of beryllium pebbles, irradiation behavior evaluation and reprocessing technology have been started since 1990. In this presentation, study on the neutron irradiation behavior of beryllium as the neutron multiplier with JMTR was reviewed from the point of tritium release, thermal properties, mechanical properties and reprocessing technology. (author)

  2. Status of material development for lifetime expansion of beryllium reflector

    International Nuclear Information System (INIS)

    Beryllium has been used as the reflector element material in the reactor, specifically S-200F structural grade beryllium manufactured by Materion Brush Beryllium and Composites (former, Brush Wellman Inc.). As a part of the reactor upgrade, the Japan Atomic Energy Agency (JAEA) also has carried out the cooperation experiments to extend the operating lifetime of the beryllium reflector elements. It will first be necessary to determine which of the material's physical, mechanical and chemical properties will be the most influential on that choice. The irradiation testing plans to evaluate the various beryllium grades are also briefly considered and prepared. In this paper, material selection, irradiation test plan and PEI development for lifetime expansion of beryllium are described for material testing reactors. (author)

  3. Characterization of plasma sprayed beryllium ITER first wall mockups

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R.G.; Vaidya, R.U.; Hollis, K.J. [Los Alamos National Lab., NM (United States). Material Science and Technology Div.

    1998-01-01

    ITER first wall beryllium mockups, which were fabricated by vacuum plasma spraying the beryllium armor, have survived 3000 thermal fatigue cycles at 1 MW/m{sup 2} 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. (author)

  4. Mechanisms of hydrogen retention in metallic beryllium and beryllium oxide and properties of ion-induced beryllium nitride; Rueckhaltemechanismen fuer Wasserstoff in metallischem Beryllium und Berylliumoxid sowie Eigenschaften von ioneninduziertem Berylliumnitrid

    Energy Technology Data Exchange (ETDEWEB)

    Oberkofler, Martin

    2011-09-22

    In the framework of this thesis laboratory experiments on atomically clean beryllium surfaces were performed. They aim at a basic understanding of the mechanisms occurring upon interaction of a fusion plasma with a beryllium first wall. The retention and the temperature dependent release of implanted deuterium ions are investigated. An atomistic description is developed through simulations and through the comparison with calculations based on density functional theory. The results of these investigations are compared to the behaviour of hydrogen upon implantation into thermally grown beryllium oxide layers. Furthermore, beryllium nitride is produced by implantation of nitrogen into metallic beryllium and its properties are investigated. The results are interpreted with regard to the use of beryllium in a fusion reactor. (orig.)

  5. Plasma cleaning of beryllium coated mirrors

    Science.gov (United States)

    Moser, L.; Marot, L.; Steiner, R.; Newman, M.; Widdowson, A.; Ivanova, D.; Likonen, J.; Petersson, P.; Pintsuk, G.; Rubel, M.; Meyer, E.; Contributors, JET

    2016-02-01

    Cleaning systems of metallic first mirrors are needed in more than 20 optical diagnostic systems from ITER to avoid reflectivity losses. Currently, plasma sputtering is considered as one of the most promising techniques to remove deposits coming from the main wall (mainly beryllium and tungsten). This work presents the results of plasma cleaning of rhodium and molybdenum mirrors exposed in JET-ILW and contaminated with typical tokamak elements (including beryllium and tungsten). Using radio frequency (13.56 MHz) argon or helium plasma, the removal of mixed layers was demonstrated and mirror reflectivity improved towards initial values. The cleaning was evaluated by performing reflectivity measurements, scanning electron microscopy, x-ray photoelectron spectroscopy and ion beam analysis.

  6. Computer simulation of electronic excitations in beryllium

    CERN Document Server

    Popov, A V

    2016-01-01

    An effective method for the quantitative description of the electronic excited states of polyatomic systems is developed by using computer technology. The proposed method allows calculating various properties of matter at the atomic level within the uniform scheme. A special attention is paid to the description of beryllium atoms interactions with the external fields, comparable by power to the fields in atoms, molecules and clusters.

  7. Low cycle thermal fatigue testing of beryllium

    International Nuclear Information System (INIS)

    A novel technique has been used to test the relative low cycle thermal fatigue resistance of different grades of US and Russian beryllium, which is proposed as plasma facing armor for fusion reactor first wall, limiter and divertor components. The 30 kW electron beam test system at Sandia National Laboratories was used to sweep the beam spot along one direction at 1 Hz. This produces a localized temperature ''spike'' of 750 C for each pass of the beam. Large thermal stresses in excess of the yield strength are generated, due to very high spot heat flux, 25 MWm-2. Cyclic plastic strains on the order of 0.6% produced visible cracking on the heated surface in less than 3000 cycles. An in-vacuo fiber optic borescope was used to visually inspect the beryllium surfaces for crack initiation. Grades of US beryllium tested included: S-65C, S-65H, S-200F, S200F-H, SR-200, I-400, extruded high purity, HIP'd spherical powder, porous beryllium (94 and 98% dense), Be/30%, BeO, Be/60% BeO, and TiBe12. Russian grades included: TPG-56, TShGT, DShG-200, and TSHG-56. Both thenumber of cycles tocrack initiation and the depth of crack propagation, were measured. The most fatigue resistant grades were S-65C, DShG-200, TShGT and TShG-56. Rolled sheet Be (SR-200) showed excellent crack propagation resistance in the plane of rolling, despite early formation of delamination cracks. Only one sample showed no evidence of surface melting, Extruded (T). Metallographic and chemical analyses are provided. Good agreement was found between the measured depth of cracks and a 2-D elastic-plastic finite element stress analysis. (orig.)

  8. Dynamic behaviour of S200F beryllium

    International Nuclear Information System (INIS)

    Compression tests have been made on a large scale of strain, strain rate (up to 2000 s-1) and temperature (between 20 C and 300 C). From these experiences, we have calculated a constitutive model for beryllium S200F, which can be used by computer codes. Its formulation is not far from Steinberg, Cochran and Guinan's. But in our case, the influences of temperature and strain rate appear clearly within the expression. To validate our equation, we have used it in a computer code. Its extrapolation for higher strain rates is in good agreement with experiments such as Taylor impact tests or plate impact tests (strain rates greater than 104 s-1). With micrography, we could settle a link between the main strain mode within the material, and the variation of one parameter of the model. Beside the constitutive model, we have shown that shock loaded beryllium behaves in two different ways. If the strain rate is lower than 5.106 s-1, then it is proportional to the squared shock pressure. Beyond, it is a linear function of shock pressure to the power of four. By a spall study on beryllium, we have confirmed that it is excessively fragile. Its fracture is sudden, at a strength near 1 GPa. (author)

  9. Permeation behavior of deuterium implanted into beryllium

    International Nuclear Information System (INIS)

    Study on Implantation Driven Permeation (IDP) behavior of deuterium through pure beryllium was investigated as a part of the research to predict the tritium permeation through the first wall components ITER (International Thermonuclear Experimental Reactor). The permeation experiments were carried out with two beryllium specimens, one was an unannealed specimen and the other was that annealed at 1173 K. The permeation flux was measured as a function of specimen temperature and incident ion flux. Surface analysis of specimen was also carried out after the permeation experiment. Permeation was observed only with the annealed specimen and no significant permeation was observed with unannealed specimen under the present experimental condition (maximum temperature: 685 K, detection limit: 1x1013 D atoms/m2s). It could be attributed that the intrinsic lattice defects, which act as diffusion preventing site, decreased with the specimen annealing. Based on the result of steady and transient permeation behavior and surface analysis, it was estimated that the deuterium permeation implanted into annealed beryllium was controlled by surface recombination due to the oxide layer on the surface of the permeated side. (author)

  10. Interaction of nitrogen ions with beryllium surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Dobes, Katharina [Institute of Applied Physics, TU Wien, Association EURATOM ÖAW, Vienna (Austria); Köppen, Martin [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Oberkofler, Martin [Max-Planck-Institut für Plasmaphysik, Boltzmannstraße 2, D-85748 Garching (Germany); Lungu, Cristian P.; Porosnicu, Corneliu [National Institute for Laser, Plasma, and Radiation Physics, Bucharest (Romania); Höschen, Till; Meisl, Gerd [Max-Planck-Institut für Plasmaphysik, Boltzmannstraße 2, D-85748 Garching (Germany); Linsmeier, Christian [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Aumayr, Friedrich, E-mail: aumayr@iap.tuwien.ac.at [Institute of Applied Physics, TU Wien, Association EURATOM ÖAW, Vienna (Austria)

    2014-12-01

    The interaction of energetic nitrogen projectiles with a beryllium surface is studied using a highly sensitive quartz crystal microbalance technique. The overall mass change rate of the beryllium sample under N{sub 2}{sup +} ion impact at an ion energy of 5000 eV (i.e. 2500 eV per N) is investigated in situ and in real-time. A strong dependency of the observed mass change rate on the nitrogen fluence (at constant flux) is found and can be attributed to the formation of a nitrogen-containing mixed material layer within the ion penetration depth. The presented data elucidate the dynamics of the interaction process and the surface saturation with increasing nitrogen fluence in a unique way. Basically, distinct interaction regimes can be discriminated, which can be linked to the evolution of the surface composition upon nitrogen impact. Steady state surface conditions are obtained at a total cumulative nitrogen fluence of ∼80 × 10{sup 16} N atoms per cm{sup 2}. In dynamic equilibrium, the interaction is marked by continuous surface erosion. In this case, the observed total sputtering yield becomes independent from the applied nitrogen fluence and is of the order of 0.4 beryllium atoms per impinging nitrogen atom.

  11. Behavior of beryllium pebbles under irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dalle-Donne, M.; Scaffidi-Argentina, F. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reactortechnik; Baldwin, D.L.; Gelles, D.S.; Greenwood, L.R.; Kawamura, H.; Oliver, B.M.

    1998-01-01

    Beryllium pebbles are being considered in fusion reactor blanket designs as neutron multiplier. An example is the European `Helium Cooled Pebble Bed Blanket.` Several forms of beryllium pebbles are commercially available but little is known about these forms in response to fast neutron irradiation. Commercially available beryllium pebbles have been irradiated to approximately 1.3 x 10{sup 22} n/cm{sup 2} (E>1 MeV) at 390degC. Pebbles 1-mm in diameter manufactured by Brush Wellman, USA and by Nippon Gaishi Company, Japan, and 3-mm pebbles manufactured by Brush Wellman were included. All were irradiated in the below-core area of the Experimental Breeder Reactor-II in Idaho Falls, USA, in molybdenum alloy capsules containing helium. Post-irradiation results are presented on density change measurements, tritium release by assay, stepped-temperature anneal, and thermal ramp desorption tests, and helium release by assay and stepped-temperature anneal measurements, for Be pebbles from two manufacturing methods, and with two specimen diameters. The experimental results on density change and tritium and helium release are compared with the predictions of the code ANFIBE. (author)

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

    Science.gov (United States)

    McCleskey, T. Mark; Ehler, Deborah S.; John, Kevin D.; Burrell, Anthony K.; Collis, Gavin E.; Minogue, Edel M.; Warner, Benjamin P.

    2010-08-24

    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.

  13. Tritium release from neutron irradiated beryllium: Kinetics, long-time annealing and effect or crack formation

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe, (Germany)

    1995-09-01

    Since beryllium is considered as one of the best neutron multiplier materials in the blanket of the next generation fusion reactors, several studies have been started to evaluate its behaviour under irradiation during both operating and accidental conditions. Based on safety considerations, tritium produced in beryllium during neutron irradiation represents one important issue, therefore it is necessary to investigate tritium transport processes by using a comprehensive mathematical model and comparing its predictions with well characterized experimental tests. Because of the difficulties in extrapolating the short-time tritium release tests to a longer time scale, also long-time annealing experiments with beryllium samples from the SIBELIUS irradiation. have been carried out at the Forschungszentrum Karlsruhe. Samples were annealed up to 12 months at temperatures up to 650{degrees}C. The inventory after annealing was determined by heating the samples up to 1050{degrees}C with a He+0.1 vo1% H{sub 2} purge gas. Furthermore, in order to investigate the likely effects of cracks formation eventually causing a faster tritium release from beryllium, the behaviour of samples irradiated at low temperature (40-50{degrees}C) but up to very high fast neutron fluences (0.8-3.9{center_dot}10{sup 22} cm{sup -2}, E{sub n}{ge}1 MeV) in the BR2 reactor has been investigated. Tritium was released by heating the beryllium samples up to 1050{degrees}C and purging them with He+0.1 vo1% H{sub 2}. Tritium release from high-irradiated beryllium samples showed a much faster kinetics than from the low-irradiated ones, probably because of crack formation caused by thermal stresses in the brittle material and/or by helium bubbles migration. The obtained experimental data have been compared with predictions of the code ANFIBE with the goal to better understand the physical mechanisms governing tritium behaviour in beryllium and to assess the prediction capabilities of the code.

  14. Thermal desorption analysis of beryllium tile pieces from JET

    International Nuclear Information System (INIS)

    Pieces of beryllium tile exposed to a D-D plasma in JET have been studied by thermal desorption spectroscopy. These tiles have a thick layer of redeposited Be-C-O with considerable hydrogen and deuterium present. The samples were heated at a constant rate of 2 C/min. from 100 C to 900 C. Desorption peaks occurred in the range of 140-480 C. There was no significant desorption at temperatures above 600 C. The amount of deuterium detected varied from a low of 8 x 1021/m2 to a high of 2.1 x 1023/m2. In one case, the amount of deuterium in a tile piece was seven times greater than the amount in a neighboring tile piece. Some of the tile pieces in the plasma-exposed region showed surface melting. Despite this, the deuterium yield from one of these pices is >1023/m2. (orig.)

  15. High sensitivity boron quantification in bulk silicon using the 11B(p,α0)8Be nuclear reaction

    International Nuclear Information System (INIS)

    There is a great need to quantify sub-ppm levels of boron in bulk silicon. There are several methods to analyze B in Si: Nuclear Reaction Analysis using the 11B(p,α0)8Be reaction exhibits a quantification limit of some hundreds ppm of B in Si. Heavy Ion Elastic Recoil Detection Analysis offers a detection limit of 5 to 10 at. ppm. Secondary Ion Mass Spectrometry is the method of choice of the semiconductor industry for the analysis of B in Si. This work verifies the use of NRA to quantify B in Si, and the corresponding detection limits. Proton beam with 1.6 up to 2.6 MeV was used to obtain the cross-section of the 11B(p,α0)8Be nuclear reaction at 170° scattering angle. The results show good agreementwith literature indicating that the quantification of boron in silicon can be achieved at 100 ppm level (high sensitivity) at LAMFI-IFUSP with about 16% uncertainty. Increasing the detection solid angle and the collected beam charge, can reduce the detection limit to less than 100 ppm meeting present technological needs.

  16. Thermal fatigue testing of a diffusion-bonded beryllium divertor mock-up under ITER relevant conditions

    International Nuclear Information System (INIS)

    Thermal response and thermal fatigue tests of four 5 mm thick beryllium tiles on a Russian divertor mock-up were completed on the Electron Beam Test System at Sandia National Laboratories. The beryllium tiles were diffusion bonded onto an OFHC copper saddleblock and a DSCu (MAGT) tube containing a porous coating. Thermal response tests were performed on the tiles to an absorbed heat flux of 5 MW/m2 and surface temperatures near 300 degrees C using 1.4 MPa water at 5.0 m/s flow velocity and an inlet temperature of 8-15 degrees C. One tile was exposed to incrementally increasing heat fluxes up to 9.5 MW/m2 and surface temperatures up to 690 degrees C before debonding at 10 MW/m2. A third tile debonded after 9200 thermal fatigue cycles at 5 MW/m2, while another debonded after 6800 cycles. In all cases, fatigue failure occurred in the intermetallic layers between the beryllium and copper. No fatigue cracking of the bulk beryllium was observed. During thermal cycling, a gradual loss of porous coating produced increasing sample temperatures. These experiments indicate that diffusion-bonded beryllium tiles can survive several thousand thermal cycles under ITER relevant conditions without failure. However, the reliability of the diffusion bonded Joint remains a serious issue

  17. Highly-focused boron implantation in diamond and imaging using the nuclear reaction 11B(p, α)8Be

    Science.gov (United States)

    Ynsa, M. D.; Ramos, M. A.; Skukan, N.; Torres-Costa, V.; Jakšić, M.

    2015-04-01

    Diamond is an especially attractive material because of its gemological value as well as its unique mechanical, chemical and physical properties. One of these properties is that boron-doped diamond is an electrically p-type semiconducting material at practically any boron concentration. This property makes it possible to use diamonds for multiple industrial and technological applications. Boron can be incorporated into pure diamond by different techniques including ion implantation. Although typical energies used to dope diamond by ion implantation are about 100 keV, implantations have also been performed with energies above MeV. In this work CMAM microbeam setup has been used to demonstrate capability to implant boron with high energies. An 8 MeV boron beam with a size of about 5 × 3 μm2 and a beam current higher than 500 pA has been employed while controlling the beam position and fluence at all irradiated areas. The subsequent mapping of the implanted boron in diamond has been obtained using the strong and broad nuclear reaction 11B(p, α)8Be at Ep = 660 keV. This reaction has a high Q-value (8.59 MeV for α0 and 5.68 MeV for α1) and thus is almost interference-free. The sensitivity of the technique is studied in this work.

  18. Luminescent reaction of lanthanum with 8-hydroxyquinoline-5-sulphonic acid and cetyltrimethyl ammonium

    International Nuclear Information System (INIS)

    The effect of surfactants on the fluorescence of REE complexes - with 8-hydroxyquinoline-5-sulphonic acid (quinozole) is investigated. The intensity of La-quinozole complex fluorescence increases by a factor of 20 in presence of cetyltrimethylammonium bromide. A complex with a ratio of La: quinozol: CTA = 1:1:1 is formed. The fluorescence intensity decreases significantly in presence of 10-fold excess of elements-quenchers (Pr, Nd). The fluorescence intensity-lanthanum concentration graph is linear over a range of 1-20 μg La. The method was used for determining lanthanum in its salts with a limit of detection 0.01 μg/ml

  19. Experiments on studying beryllium - steam interaction, determination of oxidated beryllium emissivity factor

    International Nuclear Information System (INIS)

    The report presents results of beryllium emissivity factor measurements within 700-1300 K temperature range. The tests were conducted at Institute of Atomic Energy of the National Nuclear Center of the Republic of Kazakhstan to receive experimental data for verification of calculation programs describing an accident involving water coolant discharge into ITER reactor vacuum cavity. (author)

  20. R-matrix Analysis for the 8Be System and Features in the p+7Li Reaction Over Resonance Region

    Directory of Open Access Journals (Sweden)

    Kunieda Satoshi

    2016-01-01

    Full Text Available A comprehensive R-matrix analysis is currently underway for the 8Be compound system toward a consistent evaluation of the p+7Li reaction cross-sections over the resonance energy region. In this analysis, the energy eigenvalues are fixed to the level energies given in ENSDF, and we searched for values of the boundary condition parameters as well as the reduced-width amplitudes. It is found that some additional levels are necessary to fit the resonant shape of experimental cross-sections. Besides, the channel radii obtained may be consistent with well-known physical pictures of the atomic nucleus.

  1. R-matrix Analysis for the 8Be System and Features in the p+7Li Reaction Over Resonance Region

    Science.gov (United States)

    Kunieda, Satoshi

    2016-06-01

    A comprehensive R-matrix analysis is currently underway for the 8Be compound system toward a consistent evaluation of the p+7Li reaction cross-sections over the resonance energy region. In this analysis, the energy eigenvalues are fixed to the level energies given in ENSDF, and we searched for values of the boundary condition parameters as well as the reduced-width amplitudes. It is found that some additional levels are necessary to fit the resonant shape of experimental cross-sections. Besides, the channel radii obtained may be consistent with well-known physical pictures of the atomic nucleus.

  2. Ionization energies of beryllium in strong magnetic fields

    Institute of Scientific and Technical Information of China (English)

    GUANXiao-xu; ZHANGYue-xia

    2004-01-01

    We have develop an effective frozen core approximation to calculate energy levels and ionization enegies of the beryllium atom in magnetic field strengths up to 2.35 × 105T. Systematic improvement over the Hartree-Fock results for the beryllium low-lying states has been accomplished.

  3. 10 CFR 850.20 - Baseline beryllium inventory.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Baseline beryllium inventory. 850.20 Section 850.20 Energy... Baseline beryllium inventory. (a) The responsible employer must develop a baseline inventory of the... inventory, the responsible employer must: (1) Review current and historical records; (2) Interview...

  4. Joining of beryllium by braze welding technique: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Banaim, P.; Abramov, E. [Ben-Gurion Univ. of the Negev, Beersheba (Israel); Zalkind, S.; Eden, S.

    1998-01-01

    Within the framework of some applications, there is a need to join beryllium parts to each other. Gas Tungsten Arc Braze Welds were made in beryllium using 0.3 mm commercially Aluminum (1100) shim preplaced at the joint. The welds exhibited a tendency to form microcracks in the Fusion Zone and Heat Affected Zone. All the microcracks were backfilled with Aluminum. (author)

  5. Exfoliated Pd/HNb3O8 nanosheet as highly efficient bifunctional catalyst for one-pot cascade reaction

    Science.gov (United States)

    Lee, Nahaeng; Chung, Young-Min

    2016-05-01

    Ultrathin two-dimensional metal oxide nanosheets have drawn attention as potential solid acid catalysts owing to their strong acidity, attributed to the bridged OH groups formed on the nanosheets. In this study, a new class of bifunctional acid-metal catalyst was realized by the deposition of Pd on layered niobium oxide (KNb3O8 and HNb3O8) or its exfoliated nanosheet (Pd/HNb3O8-NS) and applied to one-pot cascade deacetalization and hydrogenation. It was found that the acid strength of the support exerted a large influence not only on the promotion of the first deacetalization step, but also on the acceleration of the subsequent hydrogenation step. Comparative experiments using a series of Pd/HZSM-5 catalysts with different acidities reconfirmed the crucial role of acid strength on hydrogenation. However, the superior catalytic activity of Pd/HNb3O8-NS for hydrogenation compared to that of Pd/HZSM-5 of similar acidity suggests a more efficient ensemble effect of the strong acid sites with the nearby metal sites on the nanosheet surface. Among the catalysts used, Pd/HNb3O8-NS showed the best catalytic performance for one-pot cascade reaction affording the desired product (benzyl alcohol) in approximately 92% yield, which was 7.1 and 1.2 times higher than that of layered Pd/KNb3O8 or Pd/HNb3O8, respectively. The excellent catalytic performance of Pd/HNb3O8-NS may result from the characteristic features of nanosheets: (i) the synergistic cooperation between the bifunctional active sites and (ii) the two-dimensional open surface offering easier access of the reactants to the active sites. Although the use of NaBH4 as hydrogen source was effective in improving the initial reaction performance, the basic nature of NaBH4 adversely resulted in weakening the acid strength of the catalyst, and consequently led to a reduction in catalytic activity.

  6. Failure analysis of beryllium tile assembles following high heat flux testing for the ITER program

    International Nuclear Information System (INIS)

    The following document describes the processing, testing and post-test analysis of two Be-Cu assemblies that have successfully met the heat load requirements for the first wall and dome sections for the ITER (International Thermonuclear Experimental Reactor) fusion reactor. Several different joint assemblies were evaluated in support of a manufacturing technology investigation aimed at diffusion bonding or brazing a beryllium armor tile to a copper alloy heat sink for fusion reactor applications. Judicious selection of materials and coatings for these assemblies was essential to eliminate or minimize interactions with the highly reactive beryllium armor material. A thin titanium layer was used as a diffusion barrier to isolate the copper heat sink from the beryllium armor. To reduce residual stresses produced by differences in the expansion coefficients between the beryllium and copper, a compliant layer of aluminum or aluminum-beryllium (AlBeMet-150) was used. Aluminum was chosen because it does not chemically react with, and exhibits limited volubility in, beryllium. Two bonding processes were used to produce the assemblies. The primary process was a diffusion bonding technique. In this case, undesirable metallurgical reactions were minimized by keeping the materials in a solid state throughout the fabrication cycle. The other process employed an aluminum-silicon layer as a brazing filler material. In both cases, a hot isostatic press (HIP) furnace was used in conjunction with vacuum-canned assemblies in order to minimize oxidation and provide sufficient pressure on the assemblies for full metal-to-metal contact and subsequent bonding. The two final assemblies were subjected to a suite of tests including: tensile tests and electron and optical metallography. Finally, high heat flux testing was conducted at the electron beam testing system (EBTS) at Sandia National Laboratories, New Mexico. Here, test mockups were fabricated and subjected to normal heat loads to

  7. Preparation and characterization of beryllium doped organic plasma polymer coatings

    International Nuclear Information System (INIS)

    We report the formation of beryllium doped plasma polymerized coatings derived from a helical resonator deposition apparatus, using diethylberyllium as the organometaric source. These coatings had an appearance not unlike plain plasma polymer and were relatively stable to ambient exposure. The coatings were characterized by Inductively Coupled Plasma Mass Spectrometry and X-Ray Photoelectron Spectroscopy. Coating rates approaching 0.7 μm hr-1 were obtained with a beryllium-to-carbon ratio of 1:1.3. There is also a significant oxygen presence in the coating as well which is attributed to oxidation upon exposure of the coating to air. The XPS data show only one peak for beryllium with the preponderance of the XPS data suggesting that the beryllium exists as BeO. Diethylberyllium was found to be inadequate as a source for beryllium doped plasma polymer, due to thermal decomposition and low vapor recovery rates

  8. Protection of air in premises and environment against beryllium aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Bitkolov, N.Z.; Vishnevsky, E.P.; Krupkin, A.V. [Research Inst. of Industrial and Marine Medicine, St. Petersburg (Russian Federation)

    1998-01-01

    First and foremost, the danger of beryllium aerosols concerns a possibility of their inhalation. The situation is aggravated with high biological activity of the beryllium in a human lung. The small allowable beryllium aerosols` concentration in air poses a rather complex and expensive problem of the pollution prevention and clearing up of air. The delivery and transportation of beryllium aerosols from sites of their formation are defined by the circuit of ventilation, that forms aerodynamics of air flows in premises, and aerodynamic links between premises. The causes of aerosols release in air of premises from hoods, isolated and hermetically sealed vessels can be vibrations, as well as pulses of temperature and pressure. Furthermore, it is possible the redispersion of aerosols from dirty surfaces. The effective protection of air against beryllium aerosols at industrial plants is provided by a complex of hygienic measures: from individual means of breath protection up to collective means of the prevention of air pollution. (J.P.N.)

  9. Uncertainties and biases arising from methods approximations: the calculation of reaction rates in the PCA 8/7 configuration

    International Nuclear Information System (INIS)

    In the determination of the energy spectrum of the neutron fluxes at the surveillance and 1/4 T positions of LWRs by analyzing measured reaction rates, a calculation of these fluxes is both useful and informative in guiding the unfolding, regardless of the particular unfolding procedure used. It should thus be an important part of any unfolding procedure to be able to calculate not only the fluxes but also to estimate both the corrections to this calculation arising from various methods approximations and the uncertainties in these corrections. In at least one unfolding procedure, that utilizing a generalized least squares technique, knowledge of all uncertainties including those arising from calculational methods approximations is an essential part of the input. The particular problem addressed in this paper is the estimation of some correction factors (i.e., biases or bias factors) and their uncertainties arising from various approximations used in calculating the fluxes and reaction rates in the Pool Critical Assembly (PCA) at Oak Ridge for the 8/7 configuration. In addition, the uncertainties in the calculated fluxes and reaction rates arising as the result of uncertainties in the non-nuclear data input was investigated

  10. Polarizabilities of the beryllium clock transition

    International Nuclear Information System (INIS)

    The polarizabilities of the three lowest states of the beryllium atom are determined from a large basis configuration interaction calculation. The polarizabilities of the 2s21Se ground state (37.73a03) and the 2s2p 3P0o metastable state (39.04a03) 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 2s21Se-2s2p 3P0o clock transition. Magic wavelengths for simultaneous trapping of the ground and metastable states are also computed.

  11. Synthesis and Optical Characterization of Mixed Ligands Beryllium Complexes for Display Device Applications

    OpenAIRE

    Vandna Nishal; Devender Singh; Raman Kumar Saini; Vijeta Tanwar; Shri Bhagwan; Sonika Kadyan; Ishwar Singh; Pratap Singh Kadyan

    2015-01-01

    Synthesis and photoluminescent behaviour of mixed ligand based beryllium complexes with 2-(2-hydroxyphenyl)benzoxazole (HPB) and 5-chloro-8-hydroxyquinoline (Clq) or 5,7-dichloro-8-hydroxyquinoline (Cl2q) or 2-methyl-8-hydroxyquinoline (Meq) or 8-hydroxyquinoline (q) are reported in this work. These complexes, that is, [BeHPB(Clq)], [BeHPB(Cl2q)], [BeHPB(Meq)], and [BeHPB(q)], were prepared and their structures were confirmed by elemental analysis, Fourier transform infrared spectroscopy, nuc...

  12. Study of 12Be using the 11Be(9Be,8Be) transfer reaction at TRIUMF ISAC-II

    Science.gov (United States)

    Braid, Ryan; Sarazin, Fred; TIGRESS Collaboration; (PCB)2 Collaboration

    2015-10-01

    Recent results at TRIUMF and NSCL have called into question the structure of 12Be, therefore another look at this nucleus is desirable. The structure is important information for theoretical models, since it constrains the mechanism that produces parity inversion in 11Be. The 12Be structure was probed in July 2014 using the (PCB)2 array (Printed Circuit Board Based Charged Particle) inside TIGRESS (TRIUMF - ISAC Gamma Ray Escape Suppressed Spectrometer) at TRIUMF using the 11Be(9Be,8Be)12Be reaction at 55 MeV in inverse kinematics. A second set of data at 30 MeV was collected. This reaction has numerous advantages over the traditional (d,p) method, foremost of which is the 8Be --> 2 α breakup since it allows for very clean identification and tagging. Additionally, TIGRESS will allow precise γ-tagging for the excited states. The initial data and analysis will be presented in this talk. This work is partially supported by the US Department of Energy through Grant/Contract No. DE-FG03-93ER40789 (Colorado School of Mines).

  13. Electronic structure of beryllium fluoride

    International Nuclear Information System (INIS)

    Vacuum-ultraviolet reflectance, absorptance, and photoelectron spectroscopy of vitreous and crystalline BeF2 are reported. The data are interpreted with reference to self-consistent unrestricted Hartree-Fock cluster calculations also presented in this paper. The first allowed exciton reflectance peak in crystalline BeF2 is at 12.9 eV, similar to the 12.8-eV peak found in the glass. Optical transmission of bulk samples extends at least to 9.5 eV, and can be assumed to be impurity limited in available material. Calculations of several defect and impurity levels are presented. Since the calculations presented here indicate that BeF2 should have an optically forbidden band edge similar to that in SiO2, the ultimate transparency range of purified BeF2 will depend on the forbidden exciton absorption, not yet observable above the impurity background. Grazing-incidence reflectance spectra near the Be2+ K edge are interpreted in terms of a core exciton state lying at or slightly below the conduction-band minimum as determined from x-ray photoelectron data and the optical band gap

  14. Thermokinetics on the reaction of formation of Dy[(C5H8NS2)3(C12H8N2)

    Institute of Scientific and Technical Information of China (English)

    GAO Shengli; CHEN Sanping; JIAO Baojuan; SHUAI Qi; SHI Qizhen

    2005-01-01

    The enthalpy change of formation of the reaction of hydrous dysprosium chloride meter. Thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy), rate constant and kinetics parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of the reaction have also been calculated. The enthalpy change of the solid-phase reaction at 298.15 K has been obtained as (53.59 ± 0.29)liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction.

  15. Conceptual design of the beryllium rotating target for the ESS-Bilbao facility

    Energy Technology Data Exchange (ETDEWEB)

    Terrón, S., E-mail: santiago.terron@essbilbao.org [ESS-Bilbao, Parque Tecnológico Bizkaia, Laida Bidea, Edificio 207 B Planta Baja. 48160 Derio (Spain); Instituto de Fusión Nuclear - UPM, ETS Ingenieros Industriales, C José Gutiérrez Abascal, 2, 28006 Madrid (Spain); Sordo, F.; Magán, M.; Ghiglino, A.; Martínez, F.; Vicente, P.J. de; Vivanco, R. [ESS-Bilbao, Parque Tecnológico Bizkaia, Laida Bidea, Edificio 207 B Planta Baja. 48160 Derio (Spain); Instituto de Fusión Nuclear - UPM, ETS Ingenieros Industriales, C José Gutiérrez Abascal, 2, 28006 Madrid (Spain); Thomsen, K. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Perlado, J.M. [Instituto de Fusión Nuclear - UPM, ETS Ingenieros Industriales, C José Gutiérrez Abascal, 2, 28006 Madrid (Spain); Bermejo, F.J. [Instituto de Estructura de la Materia, IEM-CSIC, Consejo Superior de Investigaciones Científicas, Serrano 123, 28006 Madrid (Spain); ESS-Bilbao, Parque Tecnológico Bizkaia, Laida Bidea, Edificio 207 B Planta Baja. 48160 Derio (Spain); Abánades, A. [Instituto de Fusión Nuclear - UPM, ETS Ingenieros Industriales, C José Gutiérrez Abascal, 2, 28006 Madrid (Spain)

    2013-10-01

    The ESS-Bilbao facility, hosted by the University of the Basque Country (UPV/EHU), envisages the operation of a high-current proton accelerator delivering beams with energies up to 50 MeV. The time-averaged proton current will be 2.25 mA, delivered by 1.5 ms proton pulses with a repetition rate of 20 Hz. This beam will feed a neutron source based upon the Be (p,n) reaction, which will enable the provision of relevant neutron experimentation capabilities. The neutron source baseline concept consists in a rotating beryllium target cooled by water. The target structure will comprise a rotatable disk made of 6061-T6 aluminium alloy holding 20 beryllium plates. Heat dissipation from the target relies upon a distribution of coolant-flow channels. The practical implementation of such a concept is here described with emphasis put on the beryllium plates thermo-mechanical optimization, the chosen coolant distribution system as well as the mechanical behavior of the assembly. -- Highlights: • The conceptual design of ESS-Bilbao neutron production target has been carried out. • This device is a rotating disk holding Be elements cooled by water. • Thermo-mechanical and lifespan behavior of the Be elements have been analyzed. • Disk structure ensures coolability and a proper mechanical behavior of the assembly.

  16. Assessment of the feasibility and advantages of beryllium recycling

    International Nuclear Information System (INIS)

    This paper proposes a generic route for the recycling of beryllium from fusion reactors, based on critical issues associated with beryllium pebbles after their service life in the HCPB breeding blanket. These critical issues are the high tritium inventory, the presence of long-lived radionuclides (among which transuranics due to traces of uranium in the base metal), and the chemical toxicity of beryllium. On the basis of the chemical and radiochemical characteristics of the neutron irradiated beryllium pebbles, we describe a possible recycling route. The first step is the detritiation of the material. This can be achieved by heating the pebbles to 800 oC under an argon flow. The argon gas avoids oxidation of the beryllium, and at the proposed temperature the tritium inventory is readily released from the pebbles. In a second step, the released tritium can be oxidised on a copper oxide bed to produce tritiated water, which is consistent with the current international strategy to convert all kinds of tritiated waste into tritiated water, which can subsequently be treated in a water detritiation plant. Removal of radionuclides from the beryllium pebbles may be achieved by several types of chloride processes. The first step is to pass chlorine gas (in an argon flow) over the pebbles, thus yielding volatile BeCl2. This beryllium chloride can then be purified by fractional distillation. As a small fraction of the beryllium chloride contains the long-lived 10Be isotope, 10BeCl2 has to be separated from 9BeCl2, which could be achieved by centrifugal techniques. The product can then be reduced to obtain high-purity metallic beryllium. Two candidate reduction methods were identified: fused salt electrolysis and thermal decomposition. Both these methods require laboratory parametric studies to maximise the yield and achieve a high purity metal, before either process can be upgraded to a larger scale. The eventual product of the chloride reduction process must be a high purity

  17. Physical properties of beryllium oxide - Irradiation effects

    International Nuclear Information System (INIS)

    This work has been carried out in view of determining several physical properties of hot-pressed beryllium oxide under various conditions and the change of these properties after irradiation. Special attention has been paid on to the measurement of the thermal conductivity coefficient and thermal diffusivity coefficient. Several designs for the measurement of the thermal conductivity coefficient have been achieved. They permit its determination between 50 and 300 deg. C, between 400 and 800 deg. C. Some measurements have been made above 1000 deg. C. In order to measure the thermal diffusivity coefficient, we heat a perfectly flat surface of a sample in such a way that the heat flux is modulated (amplitude and frequency being adjustable). The thermal diffusivity coefficient is deduced from the variations of temperature observed on several spots. Tensile strength; compressive strength; expansion coefficient; sound velocity and crystal parameters have been also measured. Some of the measurements have been carried out after neutron irradiation. Some data have been obtained on the change of the properties of beryllium oxide depending on the integrated neutron flux. (author)

  18. Beryllium containing plasma interactions with ITER materials

    International Nuclear Information System (INIS)

    A beryllium-seeded deuterium plasma is used in PISCES-B to investigate mixed-material erosion and redeposition properties of ITER relevant divertor materials. The beryllium containing plasma simulates the erosion of first wall material into the ITER sol plasma and its subsequent flow toward the carbon divertor plates. The experiments are designed to quantify the behavior of plasma created mixed Be/C and Be/W surfaces. Developing an understanding of the mixed material surface behavior is crucial to accurately predicting the tritium accumulation rate within the ITER vacuum vessel. The temporal evolution of the plasma interactions with the various mixed surfaces are examined to better understand the fundamental mechanisms in play at the surface and to allow scaling of these results to the conditions expected in the ITER divertor. A new periodic heat pulse deposition system is also installed on PISCES-B to simulate the transient temperature excursions of surfaces expected to occur in the ITER divertor during ELMs and other off-normal events. These periodically applied heat pulses allow us to study the effects of transient power loading on the formation, stability and tritium content of mixed-material surfaces that are created during the experiments. (author)

  19. Breakup branches of Borromean beryllium-9

    International Nuclear Information System (INIS)

    The breakup reaction 9Be(4He, 3α)n was measured using an array of four double-sided silicon strip detectors at beam energies of 22 and 26 MeV. Excited states in 9Be up to 12 MeV were populated and reconstructed through the measurement of the charged reaction products. It is proposed that limits on the spins and parities of the states can be derived from the way that they decay. Various breakup paths for excited states in 9Be have been explored including the 8Beg.s. + n, 8Be2+ + n and 5Heg.s. + 4He channels. By imposing the condition that the breakup proceeded via the 8Be ground state, clean excitation spectra for 9Be were reconstructed. The remaining two breakup channels were found to possess strongly-overlapping kinematic signatures and more sophisticated methods (referenced) are required to completely disentangle these other possibilities. Emphasis is placed on the development of the experimental analysis and the usefulness of Monte-Carlo simulations for this purpose

  20. Breakup branches of Borromean beryllium-9

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R., E-mail: r.smith.3@pgr.bham.ac.uk; Freer, M.; Wheldon, C.; Curtis, N.; Ashwood, N. I.; Barr, M.; Kokalova, Tz.; Malcolm, J. D.; Ziman, V. A. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Almaraz-Calderon, S.; Aprahamian, A.; Bucher, B.; Couder, M.; Fang, X.; Jung, F.; Lu, W.; Roberts, A.; Tan, W. P. [Institute for Structure and Nuclear Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Copp, P.; Lesher, S. R. [Department of Physics, University of Wisconsin - La Crosse, La Crosse, WI 54601 (United States); and others

    2015-10-15

    The breakup reaction {sup 9}Be({sup 4}He, 3α)n was measured using an array of four double-sided silicon strip detectors at beam energies of 22 and 26 MeV. Excited states in {sup 9}Be up to 12 MeV were populated and reconstructed through the measurement of the charged reaction products. It is proposed that limits on the spins and parities of the states can be derived from the way that they decay. Various breakup paths for excited states in {sup 9}Be have been explored including the {sup 8}Be{sub g.s.} + n, {sup 8}Be{sub 2{sup +}} + n and {sup 5}He{sub g.s.} + {sup 4}He channels. By imposing the condition that the breakup proceeded via the {sup 8}Be ground state, clean excitation spectra for {sup 9}Be were reconstructed. The remaining two breakup channels were found to possess strongly-overlapping kinematic signatures and more sophisticated methods (referenced) are required to completely disentangle these other possibilities. Emphasis is placed on the development of the experimental analysis and the usefulness of Monte-Carlo simulations for this purpose.

  1. Breakup branches of Borromean beryllium-9

    Science.gov (United States)

    Smith, R.; Freer, M.; Wheldon, C.; Curtis, N.; Almaraz-Calderon, S.; Aprahamian, A.; Ashwood, N. I.; Barr, M.; Bucher, B.; Copp, P.; Couder, M.; Fang, X.; Goldring, G.; Jung, F.; Kokalova, Tz.; Lesher, S. R.; Lu, W.; Malcolm, J. D.; Roberts, A.; Tan, W. P.; Ziman, V. A.

    2015-10-01

    The breakup reaction 9Be(4He, 3α)n was measured using an array of four double-sided silicon strip detectors at beam energies of 22 and 26 MeV. Excited states in 9Be up to 12 MeV were populated and reconstructed through the measurement of the charged reaction products. It is proposed that limits on the spins and parities of the states can be derived from the way that they decay. Various breakup paths for excited states in 9Be have been explored including the 8Beg.s. + n, 8Be2+ + n and 5Heg.s. + 4He channels. By imposing the condition that the breakup proceeded via the 8Be ground state, clean excitation spectra for 9Be were reconstructed. The remaining two breakup channels were found to possess strongly-overlapping kinematic signatures and more sophisticated methods (referenced) are required to completely disentangle these other possibilities. Emphasis is placed on the development of the experimental analysis and the usefulness of Monte-Carlo simulations for this purpose.

  2. Condensation reaction of 3-[(8Z)-8-pentadecenyl]phenol and 3-[(8Z,11Z)-8,11,14-pentadecatrienyl]phenol with several indoles and their application to whitening effects utility; 3-[(8Z)-8-pentadecenyl] phenol oyobi 3-[(8Z,11Z)-8,11,14-pentadecatrienyl] phenol to sushu no indole kagobutsu tono shukugo hanno narabini bihaku koka

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, M.; Sakakiyama, T.; Fujihara, Y. [Kinki University, Osaka (Japan). Faculty of Engineering; Tada, T.; Shimomura, K.; Iida, K.; Yamabe, Y. [Mikimoto Pharmaceutical and Co. Ltd., Mie (Japan)

    1997-08-20

    This paper reports on compounds and their whitening effects as derived from condensation reactions between two kinds of cardanols separated from oil in cashew nut shells made in Indonesia (1): 3-[(8 Z)-8- pentadecenyl] phenol and (2): 3-[(8 Z, 11Z)-8, 11, 14-pentadecatrienyl] phenol and seven kinds of indole compounds. Tyrosinase activity inhibition test, activated oxygen suppression effect test and hyaluronidase activity inhibition test were performed to discuss the effectiveness of these 14 kinds of cardanol derivatives as whitening pharmaceuticals. High hyaluronidase activity inhibition and good tyrosinase activity inhibition were recognized on three kinds of compounds synthesized from the (1) and 5-methoxyindole-2-carbonic acid, 5-hydroxyindole-3-acietic acid and 5-methoxy-2-methyl-3-indole acetic acid. 13 refs., 1 fig., 2 tabs.

  3. Reaction kinetics aspect of U3O8 kernel with gas H2 on the characteristics of activation energy, reaction rate constant and O/U ratio of UO2 kernel

    International Nuclear Information System (INIS)

    The reaction kinetics aspect of U3O8 kernel with gas H2 on the characteristics of activation energy, reaction rate constant and O/U ratio of UO2 kernel had been studied. U3O8 kernel was reacted with gas H2 in a reduction furnace at varied reaction time and temperature. The reaction temperature was varied at 600, 700, 750 and 850 °C with a pressure of 50 mmHg for 3 hours in gas N2 atmosphere. The reation time was varied at 1, 2, 3 and 4 hours at a temperature of 750 °C using similar conditions. The reaction product was UO2 kernel. The reaction kinetic aspect between U3O8 and gas H2 comprised the minimum activation energy (ΔE), the reaction rate constant and the O/U ratio of UO2 kernel. The minimum activation energy was determined from a straight line slope of equation ln [{Db. Ro{(1 - (1 - Xb)⅓} / (b.t.Cg)] = -3.9406 x 103 / T + 4.044. By multiplying with the straight line slope -3.9406 x 103, the ideal gas constant (R) 1.985 cal/mol and the molarity difference of reaction coefficient 2, a minimum activation energy of 15.644 kcal/mol was obtained. The reaction rate constant was determined from first-order chemical reaction control and Arrhenius equation. The O/U ratio of UO2 kernel was obtained using gravimetric method. The analysis result of reaction rate constant with chemical reaction control equation yielded reaction rate constants of 0.745 - 1.671 s-1 and the Arrhenius equation at temperatures of 650 - 850 °C yielded reaction rate constants of 0.637 - 2.914 s-1. The O/U ratios of UO2 kernel at the respective reaction rate constants were 2.013 - 2.014 and the O/U ratios at reaction time 1 - 4 hours were 2.04 - 2.011. The experiment results indicated that the minimum activation energy influenced the rate constant of first-order reaction and the O/U ratio of UO2 kernel. The optimum condition was obtained at reaction rate constant of 1.43 s-1, O/U ratio of UO2 kernel of 2.01 at temperature of 750 °C and reaction time of 3 hours. The UO2 kernel produced was

  4. A New Target Design with a Beryllium Multiplier for a Lead Slowing Down Time Spectrometer (LSDTS) System

    International Nuclear Information System (INIS)

    In order to quantify fissile isotopes in the spent nuclear fuel or the recycled nuclear material, a lead slowing down time spectrometer (LSDTS) system has been investigated and developed. Among several components of LSDTS, a highly intense neutron should be produced in the system to overcome the background neutrons from spontaneous fission in the curium isotopes. Thus a thin and plate target is designed using tantalum based on the successive reactions such as a bremmstrahlung conversion (e,g) and a photoneutron production (g,n). The beam energy of incident electrons is as high as 35 MeV in LSDTS system, which will decrease in the lead medium after interaction with target. It is known that the higher energy than 5 MeV is enough to produce neutrons for light elements such as beryllium and deuterium Beryllium is widely used as a reflector due to its good characteristics of neutron scattering. Above all, a neutron multiplier is a good choice for beryllium especially in a fusion facility based on the following chain reaction, Be-9 + n (>2MeV) -> 2 He-4 + 2n -1.666 MeV and the cross section is as high as about 580 mb. Using the above application, a beryllium plate is installed on back side of tantalum target in order to multiply neutrons emitting from the target. Furthermore, some sensitivity tests are carried out by changing the thickness of beryllium plate. As a computing tool, MCNPX-2.5 code, a popular Monte Carlo three dimensional code, is taken into consideration

  5. Reactions of vitamin E and its model compound 2,2,5,7,8-pentamethylchroman-6-ol with ozone

    Energy Technology Data Exchange (ETDEWEB)

    Liebler, D.C. [Univ. of Arizona, Tucson (United States); Matsumoto, Shigenobu; Matsuo, Mitsuyoshi [Tokyo Metropolitan Institute of Gerontology, Tokyo (Japan); Iitaka, Yoichi [Nishi Tokyo Univ., Yamanashi (Japan)

    1993-01-01

    Reaction of vitamin E [(R,R,R,)-{alpha}-tocopherol] with ozone in acetonitrile yielded {alpha}-tocopheryl quinone and its precursor 8{alpha}-hydroxytocopherone, which accounted for approximately 30% of the products at <50% {alpha}-tocopherol oxidation. In addition, two novel products were identified as epimers of 10-acetyl-7-(4{prime},8{prime},12{prime}-trimethyl tridecyl)-3,4,7-trimethyl-2-oxo - 1,6-dioxaspiro[4.5]-deca-3,9-diene. These spiro products were formed in equal amounts in a combined yield of approximately 33% after complete {alpha}-tocpherol oxidation. Ozonation of the vitamin E model compound 2,2,5,7,8-pentamethylchroman-6-ol yielded an analogous spiro product, 10-acetyl-3,4,7,7-tetramethyl-2-oxo-1,6-dioxaspiro[4.5]deca-3,9-diene, whose structure was confirmed by X-ray crystallography. The spiro products may be formed by ozone addition to the chroman ring and subsequent rearrangement to ring-opened hydroxyacid products, which yield spiro products by ring closure due to dehydration. Novel spiro products formed by ozonation of vitamin E may be unique markers of ozone interaction with lipid structures that contain vitamin E. 39 refs., 3 figs., 1 tab.

  6. Fluorimetric method for determination of Beryllium; Determinazione fluorimetrica del berillio

    Energy Technology Data Exchange (ETDEWEB)

    Sparacino, N.; Sabbioneda, S. [ENEA, Centro Ricerche Saluggia, Vercelli (Italy). Dip. Energia

    1996-10-01

    The old fluorimetric method for the determination of Beryllium, based essentially on the fluorescence of the Beryllium-Morine complex in a strongly alkaline solution, is still competitive and stands the comparison with more modern methods or at least three reasons: in the presence of solid or gaseous samples (powders), the times necessary to finalize an analytic determination are comparable since the stage of the process which lasts the longest is the mineralization of the solid particles containing Beryllium, the cost of a good fluorimeter is by far Inferior to the cost, e. g., of an Emission Spectrophotometer provided with ICP torch and magnets for exploiting the Zeeman effect and of an Atomic absorption Spectrophotometer provided with Graphite furnace; it is possible to determine, fluorimetrically, rather small Beryllium levels (about 30 ng of Beryllium/sample), this potentiality is more than sufficient to guarantee the respect of all the work safety and hygiene rules now in force. The study which is the subject of this publication is designed to the analysis procedure which allows one to reach good results in the determination of Beryllium, chiefly through the control and measurement of the interference effect due to the presence of some metals which might accompany the environmental samples of workshops and laboratories where Beryllium is handled, either at the pure state or in its alloys. The results obtained satisfactorily point out the merits and limits of this analytic procedure.

  7. High-Pressure/High-Temperature Studies of the Low-Z materials - Beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Evans, W J; Cynn, H

    2006-03-02

    The high-pressure/temperature phase diagrams of materials are largely unexplored. Combined laser heating/x-ray diffraction capabilities applied to diamond anvil cell experiment provide unique opportunities to study materials over a broad range of temperature (several 1000 K's) and pressure (several 100 GPa's). Of particular interest are high temperature phase transitions including solid-solid and melting transitions in geophysically and technologically important systems. Data derived from these experiments serve to extend our scientific understanding of materials and evaluate theoretical predictions. Using the laser heating (LH) and angle dispersive x-ray diffraction (ADXD) capabilities at BL10XU at SPring-8, we have studied several materials at high-pressure/temperature. This report will summarize results of our studies of solid-solid and melting transitions of beryllium at high pressures and high temperatures. The phase diagram of beryllium is largely unexplored, and the limited data that is available relies on indirect means to establish phase lines and phase transitions (see figure 1)[1]. At ambient pressure an hcp-bcc phase transition has been observed at 1523 K with a subsequent melt transition at 1551 K. Using electrical conductivity, Francois and Contre[2] inferred that the hcp-bcc phase line had a negative slope with pressure. It should be noted that this was established using indirect evidence, and the bcc phase was not definitively identified using, for example, x-ray diffraction. Many subsequent studies have searched for the extension of this phase line, but have failed to find the hcp-bcc transition at room temperature up to pressures approaching 200 GPa[1]. The goal of our studies at BL10XU/SPring-8 was to identify stronger evidence for this hcp-bcc phase line, extend the pressure range and measure the lattice parameters at high pressure. Laser-heated angle-dispersive x-ray diffraction studies of beryllium at high pressures are challenging

  8. Quantitative differential thermal analysis study of the U3O8-Al thermite reaction

    Energy Technology Data Exchange (ETDEWEB)

    Pasto, A. E.; Copeland, G. L.; Martin, M. M.

    1980-01-01

    Concerns about proliferation resistance of nuclear fuel cycles and fuels have prompted a reinvestigation of U/sub 3/O/sub 8/-Al cermet fuels currently being used in research and test reactors. In particular, higher loadings of U/sub 3/O/sub 8/ are being considered. These new fuel compositions are in the region of maximum possible thermal energy release from the high-temperature thermite reaction between the U/sub 3/O/sub 8/ and aluminum components. This study was initiated to quantitatively measure the amount of reaction heat evolved. A differential thermal analysis system was calibrated with materials of known heat of reaction. Subsequently, specimens of high-uranium-loaded U/sub 3/O/sub 8/-Al powder mixtures were analyzed. Thermite reaction heat measured for these specimens was much lower than expected. Specimens of simulated fuel plates showed similar low results. Possible reasons for this behavior are discussed.

  9. Observation of a chemically labile, noncovalent enzyme intermediate in the reaction of metal-dependent Aquifex pyrophilus KDO8PS by time-resolved mass spectrometry

    OpenAIRE

    Roberts, Anne; Furdui, Cristina; Anderson, Karen S.

    2010-01-01

    The direct detection of intermediates in enzymatic reactions can yield important mechanistic insights but may be difficult due to short intermediate lifetimes and chemical instability. Using a rapid-mixing device coupled with electrospray ionization time-of-flight mass spectrometry, the noncova-lent hemiketal intermediate in the reaction of metal-dependent 3-deoxy-D-manno-octulosonate-8-phosphate (KDO8P) synthase from Aquifex pyrophilus was observed in the millisecond time range. Using single...

  10. Development of Beryllium Vacuum Chamber Technology for the LHC

    CERN Document Server

    Veness, R; Dorn, C

    2011-01-01

    Beryllium is the material of choice for the beam vacuum chambers around collision points in particle colliders due to a combination of transparency to particles, high specific stiffness and compatibility with ultra-high vacuum. New requirements for these chambers in the LHC experiments have driven the development of new methods for the manufacture of beryllium chambers. This paper reviews the requirements for experimental vacuum chambers. It describes the new beryllium technology adopted for the LHC and experience gained in the manufacture and installation.

  11. Analysis of surface contaminants on beryllium and aluminum windows

    International Nuclear Information System (INIS)

    An effort has been made to document the types of contamination which form on beryllium windows 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. (orig.)

  12. Cosmis Lithium-Beryllium-Boron Story

    Science.gov (United States)

    Vangioni-Flam, E.; Cassé, M.

    Light element nucleosynthesis is an important chapter of nuclear astrophysics. Specifically, the rare and fragile light nuclei Lithium, Beryllium and Boron (LiBeB) are not generated in the normal course of stellar nucleosynthesis (except Lithium-7) and are, in fact, destroyed in stellar interiors. This characteristic is reflected in the low abundance of these simple species. Up to recently, the most plausible interpretation was that galactic cosmic rays (GCR) interact with interstellar CNO to form LiBeB. Other origins have been also identified, primordial and stellar (Lithium-7) and supernova neutrino spallation (Lithium-7 and Boron-11). In contrast, Beryllium-9, Boron-10 and Lithium-6 are pure spallative products. This last isotope presents a special interest since the Lithium-7/Lithium-6 ratio has been measured in a few halo stars offering a new constraint on the early galactic evolution. However, in the nineties, new observations prompted astrophysicists to reassess the question. Optical measurements of the beryllium and boron abundances in halo stars have been achieved by the 10 meters KECK telescope and the Hubble Space Telescope. These observations indicate a quasi linear correlation between Be and B vs Fe, at least at low metallicity, unexpected on the basis of GCR scenario, predicting a quadratic relationship. As a consequence, the origin and the evolution of the LiBeB nuclei has been revisited. This linearity implies the acceleration of C and O nuclei freshly synthesized and their fragmentation on the the interstellar Hydrogen and Helium. Wolf-Rayet stars and supernovae via the shock waves induced, are the best candidates to the acceleration of their own material enriched into C and O; so LiBeB is produced independently of the Interstellar Medium chemical composition. Moreover, neutrinos emitted by the newly born neutron stars interacting with the C layer of the supernova could produce specifically Lithium-7 and Boron-11. This process is supported by the

  13. Compatibility of refractory metals and beryllium with molten Pb-17Li

    International Nuclear Information System (INIS)

    The compatibility of V, Nb, Ta, Mo, W and Re with static eutectic mixture Pb-17Li was investigated experimentally. All these metals are very stable in the eutectic up to 600 C. Dissolution rates as well as solubilities are low. Below 600 C, a chemical reaction zone caused by initiation of an intergranular corrosion was observed. There was a strong isothermal mass transfer to the crucible wall. Diffusion coefficients for vanadium were calculated. They are in the expected range. The behaviour of beryllium is included in this paper for comparison. Diffusion coefficients were determined. In spite of low dissolution rates a strong intergranular corrosion causes destruction of this metal. (orig.)

  14. Spectrum of neutrons emitted from a thick beryllium target bombarded with 7 MeV deuterons

    International Nuclear Information System (INIS)

    The spectrum of neutrons emitted from a thick beryllium target bombarded with 7 MeV deuterons is measured at 25 reaction angles distributed between 00 and 1580, and over the neutron energy range ≅11.0 MeV. The spectrum is determined relative to the standard 252Cf prompt-fission-neutron-spectrum using fast time-of-flight techniques. The results are presented as angle-energy differential distributions and as relative numerical group cross sections suitable for establishing a reference field for applied studies. 24 refs., 4 figs

  15. Synthesis of 3,4-dihydro-1,8-naphthyridin-2(1H-ones via microwave-activated inverse electron-demand Diels–Alder reactions

    Directory of Open Access Journals (Sweden)

    Salah Fadel

    2014-01-01

    Full Text Available Substituted 3,4-dihydro-1,8-naphthyridin-2(1H-ones have been synthesized with the inverse electron-demand Diels–Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels–Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H-ones by an efficient synthetic route.

  16. Stellar abundances of beryllium and CUBES

    CERN Document Server

    Smiljanic, R

    2014-01-01

    Stellar abundances of beryllium are useful in different areas of astrophysics, including studies of the Galactic chemical evolution, of stellar evolution, and of the formation of globular clusters. Determining Be abundances in stars is, however, a challenging endeavor. The two Be II resonance lines useful for abundance analyses are in the near UV, a region strongly affected by atmospheric extinction. CUBES is a new spectrograph planned for the VLT that will be more sensitive than current instruments in the near UV spectral region. It will allow the observation of fainter stars, expanding the number of targets where Be abundances can be determined. Here, a brief review of stellar abundances of Be is presented together with a discussion of science cases for CUBES. In particular, preliminary simulations of CUBES spectra are presented, highlighting its possible impact in investigations of Be abundances of extremely metal-poor stars and of stars in globular clusters.

  17. Beryllium reflector elements for PARR-1

    International Nuclear Information System (INIS)

    The LEU fuel of PARR-1 was designed for a discharge burnup of 35% of initial /sup 235/U loading. Recently some of the fuel elements have been discharged from the PARR-1 core after attaining the burnup closed to the design value. These fuel elements were discharged due to diminished excess reactivity although they were physically intact. After satisfactory performance of these fuel elements there has been a desire to explore the possibility of enhancing the discharge burnup by boosting up the core reactivity. Use of better reflector elements is one of the methods to obtain this goal. In this report properties of various reflector elements have been compared and it is found that use of Beryllium metal reflector elements may be a promising choice for this purpose. (author)

  18. Investigation of the ion beryllium surface interaction

    Energy Technology Data Exchange (ETDEWEB)

    Guseva, M.I.; Birukov, A.Yu.; Gureev, V.M. [RRC Kurchatov Institute, Moscow (Russian Federation)] [and others

    1995-09-01

    The self -sputtering yield of the Be was measured. The energy dependence of the Be self-sputtering yield agrees well with that calculated by W. Eckstein et. al. Below 770 K the self-sputtering yield is temperature independent; at T{sub irr}.> 870 K it increases sharply. Hot-pressed samples at 370 K were implanted with monoenergetic 5 keV hydrogen ions and with a stationary plasma (flux power {approximately} 5 MW/m{sup 2}). The investigation of hydrogen behavior in beryllium shows that at low doses hydrogen is solved, but at doses {ge} 5x10{sup 22} m{sup -2} the bubbles and channels are formed. It results in hydrogen profile shift to the surface and decrease of its concentration. The sputtering results in further concentration decrease at doses > 10{sup 25}m{sup -2}.

  19. Advances in beryllium powder consolidation simulations

    International Nuclear Information System (INIS)

    A fuzzy logic based multiobjective genetic algorithm (GA) is introduced and the algorithm is used to optimize micromechanical densification modeling parameters for warm isopressed beryllium powder, HIPed copper powder and CIPed/sintered and HIPed tantalum powder. In addition to optimizing the main model parameters using the experimental data points as objective functions, the GA provides a quantitative measure of the sensitivity of the model to each parameter, estimates the mean particle size of the powder, and determines the smoothing factors for the transition between stage 1 and stage 2 densification. While the GA does not provide a sensitivity analysis in the strictest sense, and is highly stochastic in nature, this method is reliable and reproducible in optimizing parameters given any size data set and determining the impact on the model of slight variations in each parameter

  20. Neutron and gamma emission in the fusion reaction 86Kr + 76Ge at 3,8 MeV/u

    International Nuclear Information System (INIS)

    In the present thesis the neutron and gamma emission of Compound nuclei with high excitation energy and large maximal angular momenta was studied, which are formed in fusion reactions with heavy ions. Thereby the system 86Kr + 76Ge was studied at a beam energy of 3.8 MeV/u, because here intermediate mass product nuclei arise for which the neutron emission is the dominant particle channel. For the neutron detection a detector arrangement was developed, which consistent of several NE213 liquid scintillators constructed in the Institute for Nuclear Physics. A separation of neutrons and gamma quanta is possible by pulse shape discrimination. For the determination of energy and angular distribution of the emitted neutrons 8 of these detectors were put under angles from 00 to 1050 in distances between 30 and 50 cm from the target. A further NE 213 detector of larger volume was put at -900 in 6 cm distance from the target and applied for the detection of neutrons and gamma quanta in coincidence. By this preferently events with high neutron respectively gamma multiplicity corresponding to low and high angular momentum ranges of the compound nucleus can be filtered out. For monitoring purposes the energy spectrum of the gamma quanta was registrated by a Ge(Li) detector under 1350. Additionally by three Ge(Li) detectors at 00, 900, and 1350 the angular distribution of discrete gamma lines was registrated. Here also the additional NE213 detector at -900 served as multiplicity filter. (orig.)

  1. Dosimetry of High-Energy Protons by Measurement of Beryllium-7 Formed in the Tissues

    International Nuclear Information System (INIS)

    In the course of biological experiments at the CERN cyclotron at Geneva (using 600 MeV protons) and the Saturne synchrotron at the Saclay Nuclear Studies Centre, the radioactivity induced in living beings was investigated by gamma-spectrography. Whereas most of the induced radioisotopes (gamma emitters) are short-lived, the beryllium-7 produced by spallation reactions on, in particular, oxygen, carbon and nitrogen atoms, has an activity peak which stands out abruptly from the spectrum as a whole at the 479-keV level. As its half-life is 54. 5 d, it can be recorded for a sufficiently long time. An experiment carried out with Whitsar rats given whole-body exposures of between 400 and 800 rad with 600-MeV protons and of 200 to 1000 rad with 3-GeV protons, disclosed a linear response of the Be7 activity in relation to the dose absorbed per gram of tissue. The authors compare their experimental results with the activities calculated in terms of energy on the basis of published cross-sections. The accidental exposure of human beings to proton beams can only be local. Exposure of the heads of Fauve de Bourgogne rabbits weighing approximately 2 kg show that the activity measured on the head, in relation to the rest of the body, is of the order of 1.8 ± 5. Be7 can be detected during the first days in spite of some diffusion. Relative dosimetry, indicating the scale of the accidental exposure received, is therefore possible. (author)

  2. Age hardening in beryllium-aluminum-silver alloys

    International Nuclear Information System (INIS)

    Three different alloys of beryllium-aluminum-silver were processed to powder by centrifugal atomization in a helium atmosphere. Alloy compositions were, by weight percent, Be-47.5Al-2.5Ag, Be-47Al-3Ag, and Be-46Al-4Ag. Due to the low solubility of both aluminum and silver in beryllium, the silver was concentrated in the aluminum phase, which separates from the beryllium in the liquid phase. A fine, continuous composite beryllium-aluminum microstructure was formed, which did not significantly change after hot isostatic pressing. Samples of hot isostatically pressed material were solution treated at 550 C for 1 h, followed by a water quench. Aging temperatures were 150, 175, 200, and 225 C for times ranging from half an hour to 65 h. Results indicate that peak hardness was reached in 36--40 h at 175 C and 12--16 h at 200 C aging temperature, relatively independent of alloy composition

  3. Design alternatives for cryogenic beryllium windows in an ICF cryostat

    International Nuclear Information System (INIS)

    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

  4. New facility for post irradiation examination of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, Etsuo; Kawamura, Hiroshi [Oarai Research Establishment, Ibaraki-Ken (Japan)

    1995-09-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800{degrees}C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and {sup 60}Co;7.4 MBq/day.

  5. Development of Biomarkers for Chronic Beryllium Disease in Mice

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Terry

    2013-01-25

    Beryllium is a strategic metal, indispensable for national defense programs in aerospace, telecommunications, electronics, and weaponry. Exposure to beryllium is an extensively documented occupational hazard that causes irreversible, debilitating granulomatous lung disease in as much as 3 - 5% of exposed workers. Mechanistic research on beryllium exposure-disease relationships has been severely limited by a general lack of a sufficient CBD animal model. We have now developed and tested an animal model which can be used for dissecting dose-response relationships and pathogenic mechanisms and for testing new diagnostic and treatment paradigms. We have created 3 strains of transgenic mice in which the human antigen-presenting moiety, HLA-DP, was inserted into the mouse genome. Each mouse strain contains HLA-DPB1 alleles that confer different magnitude of risk for chronic beryllium disease (CBD): HLA-DPB1*0401 (odds ratio = 0.2), HLA-DPB1*0201 (odds ratio = 15), HLA-DPB1*1701 (odds ratio = 240). Our preliminary work has demonstrated that the *1701 allele, as predicted by human studies, results in the greatest degree of sensitization in a mouse ear swelling test. We have also completed dose-response experiments examining beryllium-induced lung granulomas and identified susceptible and resistant inbred strains of mice (without the human transgenes) as well as quantitative trait loci that may contain gene(s) that modify the immune response to beryllium. In this grant application, we propose to use the transgenic and normal inbred strains of mice to identify biomarkers for the progression of beryllium sensitization and CBD. To achieve this goal, we propose to compare the sensitivity and accuracy of the lymphocyte proliferation test (blood and bronchoalveolar lavage fluid) with the ELISPOT test in the three HLA-DP transgenic mice strains throughout a 6 month treatment with beryllium particles. Because of the availability of high-throughput proteomics, we will also identify

  6. Beryllium foils for windows in counter of nuclear radiation

    International Nuclear Information System (INIS)

    Based on the optimization of the main structural characteristics (grain structure, texture, dislocation substructure) are defined modes of deformation and heat treatment of beryllium foils (purity > 99.95%), providing their excellent mechanical properties and optimized modes of deformation and heat treatment. Analyzed various technological methods rolling foils to their rational use for the practical implementation of the results of the study. It is shown that the strength and plastic properties of the foils beryllium higher than that of similar foils foreign manufacture

  7. The beryllium production at Ulba metallurgical plant (Ust-Kamenogrsk, Kazakhstan)

    Energy Technology Data Exchange (ETDEWEB)

    Dvinskykh, E.M.; Savchuk, V.V.; Tuzov, Y.V. [Ulba Metallurgical Plant (Zavod), Ust-Kamenogorsk, Abay prospect 102 (Kazakhstan)

    1998-01-01

    The Report includes data on beryllium production of Ulba metallurgical plant, located in Ust-Kamenogorsk (Kazakhstan). Beryllium production is showed to have extended technological opportunities in manufacturing semi-products (beryllium ingots, master alloys, metallic beryllium powders, beryllium oxide) and in production of structural beryllium and its parts. Ulba metallurgical plant owns a unique technology of beryllium vacuum distillation, which allows to produce reactor grades of beryllium with a low content of metallic impurities. At present Ulba plant does not depend on raw materials suppliers. The quantity of stored raw materials and semi-products will allow to provide a 25-years work of beryllium production at a full capacity. The plant has a satisfactory experience in solving ecological problems, which could be useful in ITER program. (author)

  8. Beryllium pressure vessels for creep tests in magnetic fusion energy

    International Nuclear Information System (INIS)

    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

  9. Impurities effect on the swelling of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Donne, M.D.; Scaffidi-Argentina, F. [Institut fuer Neutronenphysik und Reaktortechnik, Karlsruhe (Germany)

    1995-09-01

    An important factor controlling the swelling behaviour of fast neutron irradiated beryllium is the impurity content which can strongly affect both the surface tension and the creep strength of this material. Being the volume swelling of the old beryllium (early sixties) systematically higher than that of the more modem one (end of the seventies), a sensitivity analysis with the aid of the computer code ANFIBE (ANalysis of Fusion Irradiated BEryllium) to investigate the effect of these material properties on the swelling behaviour of neutron irradiated beryllium has been performed. Two sets of experimental data have been selected: the first one named Western refers to quite recently produced Western beryllium, whilst the second one, named Russian refers to relatively old (early sixties) Russian beryllium containing a higher impurity rate than the Western one. The results obtained with the ANFIBE Code were assessed by comparison with experimental data and the used material properties were compared with the data available in the literature. Good agreement between calculated and measured values has been found.

  10. Behaviour of Molten Beryllium with ITER Reference CFC NB31 (SNECMA) Under Moisture

    International Nuclear Information System (INIS)

    A dramatic exothermic reaction with aluminium, a carbide forming metal, has been observed in Tore Supra. A small rod of 30 mm3, acting as a temperature proof, was enclosed in a blind hole of a thermally loaded low density PAN fiber CFC 1001Z block (SGL), which reached a temperature of about 1300 oC during plasma operation. The molten aluminium had penetrated the carbon matrix through to the block's front surface. After component removal and roughly 2 months of exposure to air in the laboratory, the CFC in front of the blind hole was found to have been locally destroyed over a crater-shaped structure of 2 cm diameter. This was due to an enhanced decomposition of aluminium carbide to aluminium hydroxide. Beryllium (Be), also a carbide forming metal, is used on the ITER first wall. Carbon reinforced carbon (CFC) of type NB31 (Snecma) covers the vertical divertor targets. It is expected that beryllium material will be transported during normal and/or off normal plasma operation to the carbon based divertor targets to form beryllium carbide. During air venting or a supposed accidental in-vessel water leak event, it will react exothermically under moisture to beryllium oxide. In order to investigate to which extent the CFC structure could be modified or eventually destroyed, this reaction process has been simulated with a CFC block NB31 of size 16 x 32 x 20 mm3, where about 40 mm3 of Be S65 C (Brush Wellmann) has been placed in a previously drilled blind hole of 4 mm diameter oriented parallel to the high conductivity pitch fibers. When melted, by heating the CFC block, the Be penetrated in the carbon matrix through to the block's front surface. The front surface of the CFC was then exposed to humidity (tap water) for about 2 weeks and then stored for a further 2 months in a closed vinyl bag under atmospheric pressure after which the sample was analysed. After the exposure of the CFC to humidity, reaction products have been detected at the surface of the carbon fibre

  11. Investigation on the pulmonary effects of intermetallic beryllium compounds. Final report, January 1, 1976-December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Stemmer, K. L.

    1978-12-01

    The pulmonary response to the exposure to tantalum and niobium beryllide, and a copper beryllium alloy was investigated. The findings were compared to beryllium metal as positive control. 2.5 or 0.5 mg as beryllium were given to rats by intratracheal intubation. At 30, 60, and 90 days after exposure the response was similar with each material. There was inflammatory infiltrate by lymphocytes, macrophage accumulation, and beginning fibrosis of the terminal bronchioles. Epithelial hyperplasia occurred at, or after, 90 days. Niobium beryllide had a unique granulomatous lesion which was similar to human berylliosis. After 15 months, 8 squamous cell carcinomas and 1 adenocarcinoma were found in rats exposed to beryllium metal. No neoplasms were seen with the other materials. Solubility studies in saline and serum were conducted with the same materials. Niobium beryllide had a significantly lower solubility, namely, 0.04 in saline and 0.06 micrograms per milliliter in serum. The copper alloy was even lower at 0.02 in saline and 0.01 micrograms per milliliter in serum.

  12. Cosmogenic beryllium cycling in a natural forest setting

    Science.gov (United States)

    Conyers, Grace

    10Bemet, or cosmogenic beryllium, has a long half-life of 1.4 million years and quick adsorption on soil particles, which may make it ideal for dating soil erosion in historical context. However, there are questions on about the fundamental assumptions of the retentivity of 10Bemet. This manuscript explores these assumptions and the context of nutrient cycling in a natural forest setting. To see if 10Bemet was being cycled through the trees, and at what rate, we looked at the[10Bemet ] in the soil, 4 species of trees, and their leaves. The isotopic ratio 10Be/9Be in all four tree species was comparable to the soil on which they grow, ranging from 6-8 x 10 -9. However, there was one exception with hickory (Carya spp.) which strongly bioaccumulate beryllium with an average of 0.38 ppm dry weight in the wood. Abscised hickory leaves have a higher [Be] of 2.0 ppm, over 10 times higher than in the soil. Using standard allometric equations relating tree biomass to trunk diameter, and assuming that belowground biomass has the same [Be] as aboveground, we calculate that hickory trees at our site contain approximately 1% of the total 10Bemet under their canopy and that ~10% of this Be is cycled annually by leaf abscission. It is not clear at this point what fraction of litterfall Be is recycled into the plant, returned to the soil, or carried to groundwater as organic chelates. Hickory trees occupy an average of ~10% of the oak-hickory forest area. Assuming that trees are randomly distributed, that litterfall Be is returned to the soil, and maintaining a constant 10Bemet budget over time for simplicity, then more than half of all 10Be met in the forest soil will have passed through a hickory tree over the past 10 ky. Fully 90% of all 10Bemet will pass through a hickory tree over a period of ~25 ky. It is clear that hickory trees can transport a sizable fraction of the total 10Bemet in their nutrient cycle, and that they may be responsible for landscape-scale Be mobility.

  13. Beryllium data base for in-pile mockup test on blanket of fusion reactor, (1)

    International Nuclear Information System (INIS)

    Beryllium has been used in the fusion blanket designs with ceramic breeder as a neutron multiplier to increase the net tritium breeding ratio (TBR). The properties of beryllium, that is physical properties, chemical properties, thermal properties, mechanical properties, nuclear properties, radiation effects, etc. are necessary for the fusion blanket design. However, the properties of beryllium have not been arranged for the fusion blanket design. Therefore, it is indispensable to check and examine the material data of beryllium reported previously. This paper is the first one of the series of papers on beryllium data base, which summarizes the reported material data of beryllium. (author)

  14. Calculations of Maxwellian-averaged Cross Sections and Astrophysical Reaction Rates Using the ENDF/B-VII.0, JEFF-3.1, JENDL-3.3 and ENDF/B-VI.8 Evaluated Nuclear Reaction Data Libraries

    OpenAIRE

    Pritychenko, B.; Mughaghab, S. F.; Sonzogni, A. A.

    2009-01-01

    We calculated the Maxwellian-averaged cross sections (MACS) and astrophysical reaction rates of the stellar nucleosynthesis reactions (n,$\\gamma$), (n,fission), (n,p), (n,$\\alpha$) and (n,2n) using the ENDF/B-VII.0-, JEFF-3.1-, JENDL-3.3-, and ENDF/B-VI.8-evaluated nuclear-data libraries. Four major nuclear reaction libraries were processed under the same conditions for Maxwellian temperatures ({\\it kT}) ranging from 1 keV to 1 MeV. We compare our current calculations of the {\\it s}-process n...

  15. Synthesis and Optical Characterization of Mixed Ligands Beryllium Complexes for Display Device Applications

    Directory of Open Access Journals (Sweden)

    Vandna Nishal

    2015-01-01

    Full Text Available Synthesis and photoluminescent behaviour of mixed ligand based beryllium complexes with 2-(2-hydroxyphenylbenzoxazole (HPB and 5-chloro-8-hydroxyquinoline (Clq or 5,7-dichloro-8-hydroxyquinoline (Cl2q or 2-methyl-8-hydroxyquinoline (Meq or 8-hydroxyquinoline (q are reported in this work. These complexes, that is, [BeHPB(Clq], [BeHPB(Cl2q], [BeHPB(Meq], and [BeHPB(q], were prepared and their structures were confirmed by elemental analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and thermal analysis. The beryllium complexes exhibited good thermal stability up to ~300°C temperature. The photophysical properties of beryllium complexes were studied using ultraviolet-visible absorption and photoluminescence emission spectroscopy. The complexes showed absorption peaks due to π-π∗ and n-π∗ electronic transitions. The complexes emitted greenish blue light with peak wavelength at 496 nm, 510 nm, 490 nm, and 505 nm, respectively, consisting of high intensity. Color tuning was observed with changing the substituents in quinoline ring ligand in metal complexes. The emitted light had Commission Internationale d’Eclairage color coordinates values at x=0.15 and y=0.43 for [BeHPB(Clq], x=0.21 and y=0.56 for [BeHPB(Cl2q], x=0.14 and y=0.38 for [BeHPB(Meq], x=0.17 and y=0.41 for [BeHPB(q]. Theoretical calculations using DFT/B3LYP/6-31G(d,p method were performed to reveal the three-dimensional geometries and the frontier molecular orbital energy levels of these synthesized metal complexes.

  16. Indirect study of {sup 11}B(p,alpha{sub 0}){sup 8}Be and {sup 10}B(p,alpha){sup 7}Be reactions at astrophysical energies by means of the Trojan Horse Method: recent results

    Energy Technology Data Exchange (ETDEWEB)

    Lamia, L.; Puglia, S.M.R.; Spitaleri, C.; Romano, S. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Del Santo, M. Gimenez; Carlin, N.; Munhoz, M. Gameiro [Departamento de Fisica Nuclear, Universitade de Sao Paulo, Sao Paulo (Brazil); Cherubini, S. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Kiss, G.G. [Laboratori Nazionali del Sud, Catania (Italy); Atomki, Debrecen (Hungary); Kroha, V. [Institute for Nuclear Physics, Prague (Czech Republic); Kubono, S. [CNS, University of Tokyo, Tokyo (Japan); La Cognata, M. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Li Chengbo [China Institute of Atomic Energy, Department of Physics, Beijing (China); Pizzone, R.G. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Wen Qungang [China Institute of Atomic Energy, Department of Physics, Beijing (China); Sergi, M.L. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Szanto de Toledo, A. [Departamento de Fisica Nuclear, Universitade de Sao Paulo, Sao Paulo (Brazil); Wakabayashi, Y. [CNS, University of Tokyo, Tokyo (Japan); Advanced Science Research Center - JAEA - Ibaraki (Japan); Yamaguchi, H. [CNS, University of Tokyo, Tokyo (Japan); Zhou Shuhua [China Institute of Atomic Energy, Department of Physics, Beijing (China)

    2010-03-01

    Nuclear (p,alpha) reactions destroying the so-called 'light-elements' lithium, beryllium and boron have been largely studied in the past mainly because their role in understanding some astrophysical phenomena, i.e. mixing-phenomena occurring in young F-G stars [A.M. Boesgaard et al., Astr. Phys. J, 991, 2005, 621]. Such mechanisms transport the surface material down to the region close to the nuclear destruction zone, where typical temperatures of the order of approx10{sup 6} K are reached. The corresponding Gamow energy E{sub 0}=1.22(Z{sub x}{sup 2}Z{sub X}{sup 2}T{sub 6}{sup 2}){sup 1/3} keV [C. Rolfs and W. Rodney, 'Cauldrons in the Cosmos', The Univ. of Chicago press, 1988] is about approx10 keV if one considers the 'boron-case' and replaces in the previous formula Z{sub x}=1, Z{sub X}=5 and T{sub 6}=5. Direct measurements of the two {sup 11}B(p,alpha{sub 0}){sup 8}Be and {sup 10}B(p,alpha){sup 7}Be reactions in correspondence of this energy region are difficult to perform mainly because the combined effects of Coulomb barrier penetrability and electron screening [H.J. Assenbaum, K. Langanke and C. Rolfs, Z. Phys., 327, 1987, 461]. The indirect method of the Trojan Horse (THM) [G. Baur et al., Phys. Lett. B, 178, 1986, 135; G. Calvi et al., Nucl. Phys. A, 621, 1997, 139; C. Spitaleri et al., Phys. Rev. C, 493, 1999, 206] allows one to extract the two-body reaction cross section of interest for astrophysics without the extrapolation-procedures. Due to the THM formalism, the extracted indirect data have to be normalized to the available direct ones at higher energies thus implying that the method is a complementary tool in solving some still open questions for both nuclear and astrophysical issues [S. Cherubini et al., Astr. Phys. J, 457, 1996, 855; C. Spitaleri et al., Phys. Rev. C, 63, 2001, 005801; C. Spitaleri et al., Phys. Rev. C, 63, 2004, 055806; A. Tumino et al., Phys. Rev. Lett., 98, 2007, 252502; M. La Cognata et al., Phys

  17. Studies of the Methanol to-hydrocarbon (MTH) reaction over new 8- and 10-ring acidic zeolites

    OpenAIRE

    2009-01-01

    Abstract Developing a process in which natural gas, coal and biomass can be converted to valuable petrochemical products is becoming increasingly important. The methanolto-hydrocarbon (MTH) reactions constitute the final step in one such route. The MTH reaction is catalyzed by acidic zeolites. ZSM-22 zeolite is a less studied catalyst for the MTH reaction and has unidirectional non-interacting channels of 4.6 x 5.7 Å dimensions. In this work, ZSM-22 zeolite previously believed to b...

  18. Formation and characterization of two interconvertible side-on and end-on bonded beryllium ozonide complexes.

    Science.gov (United States)

    Zhou, Zijian; Li, Yuzhen; Zhuang, Jia; Wang, Guanjun; Chen, Mohua; Zhao, Yanying; Zheng, Xuming; Zhou, Mingfei

    2011-09-01

    The reactions of beryllium atoms with dioxygen were reinvestigated by matrix isolation infrared absorption spectroscopy. Besides the previously reported linear OBeO and cyclic Be(2)O(2) molecules, two interconvertible beryllium ozonide complexes were prepared and characterized. The BeOBe(η(2)-O(3)) complex was formed on annealing, which is characterized to be a side-on bonded ozonide complex with a planar C(2v) structure. The BeOBe(η(2)-O(3)) complex isomerized to the BeOBe(η(1)-O(3)) isomer under visible light excitation, which is an end-on bonded ozonide complex with planar C(s) symmetry. These two isomers are interconvertible; that is, visible light induces the conversion of the side-on bonded complex to the end-on bonded isomer, and vice versa on annealing. In addition, evidence is also presented for the linear BeOBeOBe cluster. PMID:21806010

  19. The unusual properties of beryllium surfaces

    International Nuclear Information System (INIS)

    Be is a ''marginal metal.'' The stable phase, hcp-Be, has a low Fermi-level density of states and very anisotropic structural and elastic properties, similar to a semiconductor's. At the Be(0001) surface, surface states drastically increase the Fermi-level density of states. The different nature of bonding in bulk-Be and at the Be(0001) surface explains the large outward relaxation. The presence of surface states causes large surface core-level shifts by inducing a higher electrostatic potential in the surface layers and by improving the screening at the surface. The authors experimental and theoretical investigations of atomic vibrations at the Be(0001) surface demonstrate clearly that Be screening of atomic motion by the surface states makes the surface phonon dispersion fundamentally different from that of the bulk. Properties of Be(0001) are so different from those of the bulk that the surface can be considered a new ''phase'' of beryllium with unique electronic and structural characteristics. For comparison they also study Be(11 bar 20), a very open surface without important surface states. Be(11 bar 20) is the only clean s-p metal surface known to reconstruct (1 x 3 missing row reconstruction)

  20. Beryllium Abundances of Solar-Analog Stars

    CERN Document Server

    Takeda, Yoichi; Honda, Satoshi; Kawanomoto, Satoshi; Ando, Hiroyasu; Sakurai, Takashi

    2011-01-01

    An extensive beryllium abundance analysis was conducted for 118 solar analogs (along with 87 FGK standard stars) by applying the spectrum synthesis technique to the near-UV region comprising the Be II line at 3131.066 A, in an attempt to investigate whether Be suffers any depletion such as the case of Li showing a large diversity. We found that, while most of these Sun-like stars are superficially similar in terms of their A(Be) (Be abundances) around the solar value within ~ +/- 0.2dex, 4 out of 118 samples turned out strikingly Be-deficient (by more than ~2 dex) and these 4 stars belong to the group of lowest v_e sin i (projected rotation velocity). Moreover, even for the other majority showing an apparent similarity in Be, we can recognize a tendency that A(Be) gradually increases with an increase in v_e sin i. These observational facts suggest that any solar analog star (including the Sun) generally suffers some kind of Be depletion during their lives, where the rotational velocity (or the angular momentu...

  1. Interaction of beryllium and hydrogen isotopes

    International Nuclear Information System (INIS)

    It has been considered that in the plasma nuclear fusion experimental devices of magnetic field confinement type, in order to reduce the energy loss due to bremsstrahlung, the use of the plasma-facing materials (PFM) of low atomic number like carbon is indispensable at present. Attention is paid to beryllium which is one of the PFMs, and its effectiveness was rocognized by the practical use in JET. When Be is considered as a PFM, it is necessary to accumulate many data on the diffusion, dissolution, permeation and surface recoupling of hydrogen isotopes, which regulate the recycling and inventory of deuterium and tritium fuel, and the relation of these factors with the physical and chemical states of Be. In this research, as the first phase of understanding the characteristics of Be as a PFM, the change of the surface condition by heating Be was investigated by X-ray photoelectron spectroscopy, and the chemical form of the Be-related substances emitted from the surface by argon or deuterium ion sputtering and their thermal behavior were measured by secondary ion mass spectrometry. The sample, the measurement and the results are reported. The diversified secondary ions of Be, Be cluster, Be oxide, hydroxide, hydride and deuteride were observed by the measurement, and their features are shown. (K.I.)

  2. Steam-chemical reactivity for irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, R.A.; McCarthy, K.A.; Oates, M.A.; Petti, D.A.; Pawelko, R.J.; Smolik, G.R. [Idaho National Engineering and Environmental Lab., Idaho Falls, ID (United States)

    1998-01-01

    This paper reports the results of an experimental investigation to determine the influence of neutron irradiation effects and annealing on the chemical reactivity of beryllium exposed to steam. The work entailed measurements of the H{sub 2} generation rates for unirradiated and irradiated Be and for irradiated Be that had been previously annealed at different temperatures ranging from 450degC to 1200degC. H{sub 2} generation rates were similar for irradiated and unirradiated Be in steam-chemical reactivity experiments at temperatures between 450degC and 600degC. For irradiated Be exposed to steam at 700degC, the chemical reactivity accelerated rapidly and the specimen experienced a temperature excursion. Enhanced chemical reactivity at temperatures between 400degC and 600degC was observed for irradiated Be annealed at temperatures of 700degC and higher. This reactivity enhancement could be accounted for by the increased specific surface area resulting from development of a surface-connected porosity in the irradiated-annealed Be. (author)

  3. Beryllium abundances in stars hosting giant planets

    CERN Document Server

    Santos, N C; Israelian, G; Mayor, M; Rebolo, R; García-Gíl, A; Pérez de Taoro, M R; Randich, S

    2002-01-01

    We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated stars. Predictions from current models are compared with the derived abundances and suggestions are provided to explain the observed inconsistencies. We show that while still not clear, the results suggest that theoretical models may have to be revised for stars with Teff<5500K. On the other hand, a comparison between planet host and non-planet host stars shows no clear difference between both populations. Although preliminary, this result favors a ``primordial'' origin for the metallicity ``excess'' observed for the planetary host stars. Under this assumption, i.e. that there would be no differences between stars with and without giant planets, the light element depletion pattern of our sample of stars may also be used to further investigate and constraint Li and Be deple...

  4. A review of the U3O8-Al reaction as a potential heat source in research and test reactor accidents

    International Nuclear Information System (INIS)

    A critical review of the literature on the U3O8-Al reaction has been conducted. The reaction in fabricated fuel plates is found to be less energetic and much slower than that in cold-pressed powder mixtures. The difference. is at least partially attributable to conversion of up to 50% of the U3O8 to U4O9 during fabrication. No definitive measurements of the amount and and rate of energy release have been made. Data are provided upon which to base calculations of energy release

  5. Search for the existence of the tetra-neutron through the He8(d,Li6)4n nuclear reaction

    International Nuclear Information System (INIS)

    The He8(d,Li6)4n reaction is studied through reverse kinematics: a radioactive beam of He8 nuclei impinges on a CD2 target. The measurement of the energy spectrum and emission angle distribution of Li6 has allowed us to determine by applying kinematics laws the excitation energy spectrum of the 4 neutrons system released in the reaction. The first chapter recalls the main features of the nucleon-nucleon interaction and reviews recent experiments on multi-neutrons. The second chapter presents the experimental setting from the production of the He8 beam at GANIL to the detection system of the reaction products via the data acquisition system. The method of the missing mass gives the mass of the 4 neutron system. The third and fourth chapters deal with the calibration of the detection system, the missing mass method is applied to the following reactions: C12(d,Li6)Be8, C12(d,t)C11 and C12(d,He3)B11. The last chapter presents the experimental results. The analysis of the excitation energy spectrum of the 4 neutron systems shows no evidence for the existence of a bound state. We get a maximal limit of 60 μb for the production cross section of a bound state. Complementary results concerning the excitation energy spectra of the di-neutron and tri-neutron released in the reactions: He8(d,Li8)2n and He8(d,Li7)3n are also presented. (A.C.)

  6. A Report on the Validation of Beryllium Strength Models

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Derek Elswick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-05

    This report discusses work on validating beryllium strength models with flyer plate and Taylor rod experimental data. Strength models are calibrated with Hopkinson bar and quasi-static data. The Hopkinson bar data for beryllium provides strain rates up to about 4000 per second. A limitation of the Hopkinson bar data for beryllium is that it only provides information on strain up to about 0.15. The lack of high strain data at high strain rates makes it difficult to distinguish between various strength model settings. The PTW model has been calibrated many different times over the last 12 years. The lack of high strain data for high strain rates has resulted in these calibrated PTW models for beryllium exhibiting significantly different behavior when extrapolated to high strain. For beryllium, the α parameter of PTW has recently been calibrated to high precision shear modulus data. In the past the α value for beryllium was set based on expert judgment. The new α value for beryllium was used in a calibration of the beryllium PTW model by Sky Sjue. The calibration by Sjue used EOS table information to model the temperature dependence of the heat capacity. Also, the calibration by Sjue used EOS table information to model the density changes of the beryllium sample during the Hopkinson bar and quasi-static experiments. In this paper, the calibrated PTW model by Sjue is compared against experimental data and other strength models. The other strength models being considered are a PTW model calibrated by Shuh- Rong Chen and a Steinberg-Guinan type model by John Pedicini. The three strength models are used in a comparison against flyer plate and Taylor rod data. The results show that the Chen PTW model provides better agreement to this data. The Chen PTW model settings have been previously adjusted to provide a better fit to flyer plate data, whereas the Sjue PTW model has not been changed based on flyer plate data. However, the Sjue model provides a reasonable fit to

  7. Erosion of beryllium under ITER – Relevant transient plasma loads

    Energy Technology Data Exchange (ETDEWEB)

    Kupriyanov, I.B., E-mail: igkupr@gmail.com [A.A. Bochvar High Technology Research Institute of Inorganic Materials, Rogova St. 5a, 123060 Moscow (Russian Federation); Nikolaev, G.N.; Kurbatova, L.A.; Porezanov, N.P. [A.A. Bochvar High Technology Research Institute of Inorganic Materials, Rogova St. 5a, 123060 Moscow (Russian Federation); Podkovyrov, V.L.; Muzichenko, A.D.; Zhitlukhin, A.M. [TRINITI, Troitsk, Moscow reg. (Russian Federation); Gervash, A.A. [Efremov Research Institute, S-Peterburg (Russian Federation); Safronov, V.M. [Project Center of ITER, Moscow (Russian Federation)

    2015-08-15

    Highlights: • We study the erosion, mass loss/gain and surface structure evolution of Be/CuCrZr mock-ups, armored with beryllium of TGP-56FW grade after irradiation by deuterium plasma heat load of 0.5 MJ/m{sup 2} at 250 °C and 500 °C. • Beryllium mass loss/erosion under plasma heat load at 250 °C is rather small (no more than 0.2 g/m{sup 2} shot and 0.11 μm/shot, correspondingly, after 40 shots) and tends to decrease with increasing number of shots. • Beryllium mass loss/erosion under plasma heat load at 500 °C is much higher (∼2.3 g/m{sup 2} shot and 1.2 μm/shot, correspondingly, after 10 shot) and tends to decrease with increasing the number of shots (∼0.26 g/m{sup 2} pulse and 0.14 μm/shot, correspondingly, after 100 shot). • Beryllium erosion value derived from the measurements of profile of irradiated surface is much higher than erosion value derived from mass loss data. - Abstract: Beryllium will be used as a armor material for the ITER first wall. It is expected that erosion of beryllium under transient plasma loads such as the edge-localized modes (ELMs) and disruptions will mainly determine a lifetime of the ITER first wall. This paper presents the results of recent experiments with the Russian beryllium of TGP-56FW ITER grade on QSPA-Be plasma gun facility. The Be/CuCrZr mock-ups were exposed to up to 100 shots by deuterium plasma streams (5 cm in diameter) with pulse duration of 0.5 ms and heat loads range of 0.2–0.5 MJ/m{sup 2} at different temperature of beryllium tiles. The temperature of Be tiles has been maintained about 250 and 500 °C during the experiments. After 10, 40 and 100 shots, the beryllium mass loss/gain under erosion process were investigated as well as evolution of surface microstructure and cracks morphology.

  8. Controlling Beryllium Contaminated Material And Equipment For The Building 9201-5 Legacy Material Disposition Project

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, T. D.; Easterling, S. D.

    2010-10-01

    This position paper addresses the management of beryllium contamination on legacy waste. The goal of the beryllium management program is to protect human health and the environment by preventing the release of beryllium through controlling surface contamination. Studies have shown by controlling beryllium surface contamination, potential airborne contamination is reduced or eliminated. Although there are areas in Building 9201-5 that are contaminated with radioactive materials and mercury, only beryllium contamination is addressed in this management plan. The overall goal of this initiative is the compliant packaging and disposal of beryllium waste from the 9201-5 Legacy Material Removal (LMR) Project to ensure that beryllium surface contamination and any potential airborne release of beryllium is controlled to levels as low as practicable in accordance with 10 CFR 850.25.

  9. Validation of cleaning method for various parts fabricated at a Beryllium facility

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Cynthia M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-15

    This study evaluated and documented a cleaning process that is used to clean parts that are fabricated at a beryllium facility at Los Alamos National Laboratory. The purpose of evaluating this cleaning process was to validate and approve it for future use to assure beryllium surface levels are below the Department of Energy’s release limits without the need to sample all parts leaving the facility. Inhaling or coming in contact with beryllium can cause an immune response that can result in an individual becoming sensitized to beryllium, which can then lead to a disease of the lungs called chronic beryllium disease, and possibly lung cancer. Thirty aluminum and thirty stainless steel parts were fabricated on a lathe in the beryllium facility, as well as thirty-two beryllium parts, for the purpose of testing a parts cleaning method that involved the use of ultrasonic cleaners. A cleaning method was created, documented, validated, and approved, to reduce beryllium contamination.

  10. Beryllium processing technology review for applications in plasma-facing components

    International Nuclear Information System (INIS)

    Materials research and development activities for the International Thermonuclear Experimental Reactor (ITER), i.e., the next generation fusion reactor, are investigating beryllium as the first-wall containment material for the reactor. Important in the selection of beryllium is the ability to process, fabricate and repair beryllium first-wall components using existing technologies. Two issues that will need to be addressed during the engineering design activity will be the bonding of beryllium tiles in high-heat-flux areas of the reactor, and the in situ repair of damaged beryllium tiles. The following review summarizes the current technology associated with welding and joining of beryllium to itself and other materials, and the state-of-the-art in plasma-spray technology as an in situ repair technique for damaged beryllium tiles. In addition, a review of the current status of beryllium technology in the former Soviet Union is also included

  11. The structure, properties and performance of plasma-sprayed beryllium for fusion applications

    International Nuclear Information System (INIS)

    Plasma-spray technology is under investigation as a method for producing high thermal conductivity beryllium coatings for use in magnetic fusion applications. Recent investigations have focused on optimizing the plasma-spray process for depositing beryllium coatings on damaged beryllium surfaces. Of particular interest has been optimizing the processing parameters to maximize the through-thickness thermal conductivity of the beryllium coatings. Experimental results will be reported on the use of secondary H2 gas additions to improve the melting of the beryllium powder and transferred-arc cleaning to improve the bonding between the beryllium coatings and the underlying surface. Information will also be presented on thermal fatigue tests which were done on beryllium coated ISX-B beryllium limiter tiles using 10 sec cycle times with 60 sec cooldowns and an International Thermonuclear Experimental Reactor (ITER) relevant divertor heat flux slightly in excess of 5 MW/m2

  12. Beryllium processing technology review for applications in plasma-facing components

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R.G.; Jacobson, L.A.; Stanek, P.W.

    1993-07-01

    Materials research and development activities for the International Thermonuclear Experimental Reactor (ITER), i.e., the next generation fusion reactor, are investigating beryllium as the first-wall containment material for the reactor. Important in the selection of beryllium is the ability to process, fabricate and repair beryllium first-wall components using existing technologies. Two issues that will need to be addressed during the engineering design activity will be the bonding of beryllium tiles in high-heat-flux areas of the reactor, and the in situ repair of damaged beryllium tiles. The following review summarizes the current technology associated with welding and joining of beryllium to itself and other materials, and the state-of-the-art in plasma-spray technology as an in situ repair technique for damaged beryllium tiles. In addition, a review of the current status of beryllium technology in the former Soviet Union is also included.

  13. The results of medical surveillance of beryllium production personnel

    International Nuclear Information System (INIS)

    The report presents results of surveillance of 1836 workers of beryllium production of Ulba Metallurgical Plant JSC with the acute and chronic forms of occupation diseases for 52 years of its operation. The dependence of acute and chronic occupation lesions on the protection degree is shown. It has been found out that, the risk of getting an occupation disease increases sharply at the moments of experimental works and at the time of reconstruction and some other extreme conditions in the production, that is supported by fixed lesions of eye mucous coat, skin and lung lesions. In this case, the readiness of people for their work in deleterious conditions and their personal responsibility for following the regulations of safety occupational standards plays a definite role. Therefore, the issues of protection are of paramount importance in prophylaxis both of acute and chronic exposure to beryllium. An influence of duration of service and occupation on chronic beryllium diseases is shown. A parallel between the lung beryllium disease and skin lesions by insoluble beryllium compounds is drawn for the first time. (author)

  14. Beryllium Target for Accelerator - Based Boron Neutron Capture Therapy

    International Nuclear Information System (INIS)

    This work is part of a project for developing Accelerator Based Boron Neutron Capture Therapy (AB- BNCT) for which the generation of neutrons through nuclear reactions like 9Be(d,n) is necessary. In this paper first results of the design and development of such neutron production targets are presented. For this purpose, the neutron production target has to be able to withstand the mechanical and thermal stresses produced by intense beams of deuterons (of 1.4 MeV with a total current of about 30mA). In particular, the target should be able to dissipate an energy density of up to 1 kW/cm2 and preserve its physical and mechanical properties for a sufficient length of time under irradiation conditions and hydrogen damage. The target is proposed to consist of a thin Be deposit (neutron producing material) on a thin W or Mo layer to stop the beam and a Cu backing to help carry away the heat load. To achieve the adhesion of the Be films on W, Mo and Cu substrates, a powder blasting technique was applied with quartz and alumina microspheres. On the other hand, Ag deposits were made on some of the substrates previously blasted to favor the chemical affinity between Beryllium and the substrate thus improving adhesion. Be deposits were characterized by means of different techniques including Electron Microscopy (Sem) and Xr Diffraction. Roughness and thickness measurements were also made. To satisfy the power dissipation requirements for the neutron production target, a microchannel system model is proposed. The simulation based on this model permits to determine the geometric parameters of the prototype complying with the requirements of a microchannel system. Results were compared with those in several publications and discrepancies lower than 10% were found in all cases. A prototype for model validation is designed here for which simulations of fluid and structural mechanics were carried out and discussed

  15. Reaction cross sections of intermediate energy sup 3 He-particles on targets from sup 9 Be to sup 2 sup 0 sup 8 Pb

    CERN Document Server

    Ingemarsson, A; Auce, A; Carlson, R F; Cowley, A A; Cox, A J; Förtsch, S V; Johansson, R; Karlson, B R; Lantz, M; Peavy, J; Stander, J A; Steyn, G F; Tibell, G

    2001-01-01

    Reaction cross sections for sup 3 He-particles have been measured for sup 9 Be, sup 1 sup 2 C, sup 1 sup 6 O, sup 2 sup 8 Si, sup 4 sup 0 Ca, sup 5 sup 8 sup , sup 6 sup 0 Ni, sup 1 sup 1 sup 2 sup , sup 1 sup 1 sup 6 sup , sup 1 sup 1 sup 8 sup , sup 1 sup 2 sup 0 sup , sup 1 sup 2 sup 4 Sn, and sup 2 sup 0 sup 8 Pb at 96, 138 and 167 MeV. The results are compared with predictions from optical model calculations using phenomenological and global optical potentials. The behaviour of the wavefunctions and of the contributions to the reaction cross sections from different regions in the nucleus is investigated. Comparisons are also made with results for alpha-particles obtained in the same energy region.

  16. Report of a technical evaluation panel on the use of beryllium for ITER plasma facing material and blanket breeder material

    International Nuclear Information System (INIS)

    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 unirradiated physical/mechanical property database; effects of irradiation on beryllium properties; tritium issues; beryllium health and safety; beryllium-coolant interactions and safety; thermal and mechanical tests; plasma erosion of beryllium; recommended beryllium grades for ITER plasma facing components; proposed manufacturing methods to produce beryllium parts for ITER; emerging beryllium materials; proposed inspection and maintenance techniques for beryllium components and coatings; time table and costs; and the importance of integrating materials and manufacturing personnel with designers

  17. Report of a technical evaluation panel on the use of beryllium for ITER plasma facing material and blanket breeder material

    Energy Technology Data Exchange (ETDEWEB)

    Ulrickson, M.A. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Manly, W.D. [Oak Ridge National Lab., TN (United States); Dombrowski, D.E. [Brush Wellman, Inc., Cleveland, OH (United States)] [and others

    1995-08-01

    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 unirradiated physical/mechanical property database; effects of irradiation on beryllium properties; tritium issues; beryllium health and safety; beryllium-coolant interactions and safety; thermal and mechanical tests; plasma erosion of beryllium; recommended beryllium grades for ITER plasma facing components; proposed manufacturing methods to produce beryllium parts for ITER; emerging beryllium materials; proposed inspection and maintenance techniques for beryllium components and coatings; time table and costs; and the importance of integrating materials and manufacturing personnel with designers.

  18. Experimental studies and modeling of processes of hydrogen isotopes interaction with beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Tazhibaeva, I.L.; Chikhray, Y.V.; Romanenko, O.G.; Klepikov, A.Kh.; Shestakov, V.P.; Kulsartov, T.V. [Science Research Inst. of Experimental and Theoretical Physics of Kazakh State Univ., Almaty (Kazakhstan); Kenzhin, E.A.

    1998-01-01

    The objective of this work was to clarify the surface beryllium oxide influence on hydrogen-beryllium interaction characteristics. Analysis of experimental data and modeling of processes of hydrogen isotopes accumulation, diffusion and release from neutron irradiated beryllium was used to achieve this purpose as well as the investigations of the changes of beryllium surface element composition being treated by H{sup +} and Ar{sup +} plasma glowing discharge. (author)

  19. Reaction and fusion cross sections for the near-symmetric system $^{129}Xe+^{nat}Sn$ from $8$ to $35$ $AMeV$

    CERN Document Server

    Manduci, L; Chbihi, A; Rivet, M F; Bougault, R; Frankland, J D; Borderie, B; Galichet, E; La Commara, M; Neindre, N Le; Lombardo, I; Pârlog, M; Rosato, E; Roy, R; Verde, G; Vient, E

    2016-01-01

    \\item[Background]Heavy-ion reactions from barrier up to Fermi energy. \\item[Purpose]Reaction and fusion cross sections determination. Fusion reactions induced by $^{129}Xe$ projectiles on $^{nat}Sn$ targets for energies ranging from $8$ A.MeV to $35$ A.MeV were measured with the INDRA $4\\pi$-array.\\\\ The evaluation of the fusion/incomplete fusion cross sections for the incident energies from 8 to 35 A.MeV is the main purpose of this paper. \\item[Method] The reaction cross sections are evaluated for each beam energy thanks to INDRA $4\\pi$-array. The events are also sorted in order to focus the study on a selected sample of events, in such a way that the fusion/fusion incomplete cross section is estimated. \\item[Results] The excitation function of reaction and fusion cross sections were measured for the heavy and nearly symmetric system $^{129}Xe + ^{nat}Sn$ from 8 to 35 A.MeV. \\item[Conclusions] The fusion-like cross-sections evaluated show a good agrement with a recent systematics for beam energies greater th...

  20. Interfacial reactions between Sn-8Zn-3Bi-xNi lead-free solders and Cu substrate during isothermal aging

    International Nuclear Information System (INIS)

    In this work, interfacial reactions of Sn-8Zn-3Bi-xNi (x = 0, 1) lead-free solders with Cu substrate and the growth of intermetallic compounds (IMCs) during isothermal aging were investigated. After soldering at 250 deg. C for 90 s, the Cu5Zn8 and CuZn5 phases formed at the Sn-8Zn-3Bi/Cu interface and only the Cu5Zn8 phase was found at the interface of the solder with addition of Ni. During aging treatment at 150 deg. C for 100, 400 and 900 h, the CuZn5 IMC at the Sn-8Zn-3Bi/Cu interface transformed to the Cu5Zn8 due to Cu atoms diffusing from Cu substrate. The Cu5Zn8 IMC layer at solder/Cu interfaces grew thicker with increasing the aging time and the growth was diffusion controlled. Moreover, the thickness of the IMC layer at the Sn-8Zn-3Bi/Cu interface was thicker than that at the Sn-8Zn-3Bi-1Ni/Cu interface. The reduction effect of Ni addition to the solder on the interfacial reaction might be attributed to the formation of the Ni5Zn21 IMC in the solder bulk, which effectively suppressed the diffusion of Zn atoms to the interface to react with Cu.

  1. Effects of helium production and radiation damage on tritium release behavior of neutron-irradiated beryllium pebbles

    International Nuclear Information System (INIS)

    The tritium release from neutron-irradiated beryllium pebbles, irradiated under different helium production (0.5-1.0 x 103 appm He) and dpa (4.2-8.6) conditions, was studied. From these results, it was clear that the apparent diffusion coefficient at 600 deg. C was significantly affected by irradiation conditions, but returned to normal values at 900 deg. C, apparently due to thermal annealing. Multiple peaks in the tritium release curve at 900 deg. C were observed

  2. The 8Li + 2H reaction studied in inverse kinematics at 3.15 MeV/nucleon using the REX-ISOLDE post-accelerator

    International Nuclear Information System (INIS)

    The reaction 8Li + 2H has been studied in inverse kinematics at the incident energy of 3.15 MeV/nucleon, using the REX-ISOLDE post-accelerator. The reaction channels corresponding to (d,p), (d,d), and (d,t) reactions populating ground states and low-lying excited states in 7-9Li have been identified and the related angular distributions extracted and compared with coupled-channels, distorted-wave Born approximation (DWBA), and coupled-reaction-channels calculations. For the inelastic and (d,t) channels we find that higher order effects are very important and hence one needs to go beyond the simple DWBA to extract reliable structure information from these processes.

  3. Lawrence Livermore Laboratory's beryllium control program for high-explosive test firing bunkers and tables

    International Nuclear Information System (INIS)

    This report on the control program to minimize beryllium levels in Laboratory workplaces includes an outline of beryllium surface, soil, and air levels and an 11-y summary of sampling results from two high-use, high-explosive test firing bunkers. These sampling data and other studies demonstrate that the beryllium control program is functioning effectively

  4. A differential thermal analysis study of the effect of tramp impurities on the exothermic U sub 3 O sub 8 -Al reactions

    Energy Technology Data Exchange (ETDEWEB)

    Gray, L.W. (Lawrence Livermore National Lab., CA (USA)); Peacock, H.B. (Savannah River Lab., Aiken, SC (USA))

    1989-12-01

    Differential thermal analysis (DTA) has been used to study the effect of impurities on aluminothermic reactions between commercial type 101 aluminum powder and U{sub 3}O{sub 8} powder. No measurable effect (solid state reactions) was found below 660{degrees}C during differential thermal analysis studies of (1) loose blended powders, (2) blended and compressed powders, (3) blended, heated, and compressed powders, or (4) blended, compressed, and heated compacts containing less than 50,000 ppM impurities from group IA halide salts and group IIA oxides. It was determined that impurities (>5 wt %) of alkali metal chlorides, and alkaline earth oxides, cause minor modifications of the reaction thermograms above 800{degrees}C for molten aluminum metal with U{sub 3}O{sub 8}. It was also determined that attempts to prepare alkali, alkaline earth, and transition metal uranates under conditions via reaction below 660{degrees}C. In similar experiments where Fe{sub 2}O{sub 3} and NiO were substituted for U{sub 3}O{sub 8}, it was determined that NaCl does modify the reactions between aluminum metal and Fe{sub 2}O{sub 3} and between aluminum metal and NiO. With increasing NaCl concentrations, the temperature for initiation of the reaction moves to lower temperatures. At 10 wt % NaCl, the exothermic thermite'' reactions between aluminum and Fe{sub 2}O{sub 3} or NiO begin at approximately 640{degrees}C. 30 refs., 17 figs., 7 tabs.

  5. A High-Performance Electrocatalyst for Oxygen Evolution Reaction: LiCo0.8 Fe0.2 O2.

    Science.gov (United States)

    Zhu, Yinlong; Zhou, Wei; Chen, Yubo; Yu, Jie; Liu, Meilin; Shao, Zongping

    2015-11-25

    Layered LiCo0.8 Fe0.2 O2 demonstrates dramatically enhanced oxygen evolution reaction (OER) activity and durability in an alkaline solution over LiCoO2 and other reported state-of-the-art catalysts, including benchmark IrO2 . This superior performance is attributed to Fe-doping-induced synergistic effects. PMID:26450659

  6. Synthesis and reactions of 4-(p-methoxybenzyl-6-[5,6,7,8-tetrahydro-2-naphthyl]-pyridazin-3(2H-one

    Directory of Open Access Journals (Sweden)

    NAGWA M.S. EL-DIN HARB

    1999-11-01

    Full Text Available The condensation of 4-(p-methoxybenzyl-6-[5,6,7,8-tetrahydro-2-naphthyl]-pyridazin-3(2H-one (3, prepared by the reaction of 6-[5,6,7,8-tetrahydro-2-naphthyl]-4,5-dihydropyridazin-3(2H-one (1 and anisaldehyde, with dimethyl sulphate, formaldehyde and acrylonitrile, and also the formation of the Mannich base, proceeded smoothly at the 2-position to give compounds 4,5,6,7, respectively. 4-p-Methoxybenzyl-3-chloro-6-[5,6,7,8-tetrahydro-2-naphthyl]-pyridazine (9 was prepared in law yield by the action of phosphorus oxychloride on 3. The reaction of 9 with benzylamine, aniline and piperidine gave 10a,b,c, respectively. 4-p-Methoxybenzyl-6-[5,6,7,8-tetrahydro-2-napthyl]pyridazine-3(2H-thione (12 was prepared either by the action of thiourea on 9, or by the reaction of 3 with phosphorus pentasulphide. The reaction of these thiones with acrylonitrile, morpholine and piperidine to give 13 and 14 a,b, respectively, were also investigated.

  7. Study of the reactions 9Be(p, α)6Li, 9Be(p,d)8Be from 300 keV to 900 keV

    International Nuclear Information System (INIS)

    The experimental results concerning the two reactions 9Be(p,α)6Li and 9Be(p,d)8Be from 300 to 900 keV are presented. The angular distribution, excitation and total cross-section curves are expressed in absolute values after a normalization carried out using results given by Weber, Davis and Marion. (authors)

  8. Estimation of beryllium ground state energy by Monte Carlo simulation

    International Nuclear Information System (INIS)

    Quantum Monte Carlo method represent a powerful and broadly applicable computational tool for finding very accurate solution of the stationary Schrödinger equation for atoms, molecules, solids and a variety of model systems. Using variational Monte Carlo method we have calculated the ground state energy of the Beryllium atom. Our calculation are based on using a modified four parameters trial wave function which leads to good result comparing with the few parameters trial wave functions presented before. Based on random Numbers we can generate a large sample of electron locations to estimate the ground state energy of Beryllium. Our calculation gives good estimation for the ground state energy of the Beryllium atom comparing with the corresponding exact data

  9. Ab Initio Simulation Beryllium in Solid Molecular Hydrogen: Elastic Constant

    Science.gov (United States)

    Guerrero, Carlo L.; Perlado, Jose M.

    2016-03-01

    In systems of inertial confinement fusion targets Deuterium-Tritium are manufactured with a solid layer, it must have specific properties to increase the efficiency of ignition. Currently there have been some proposals to model the phases of hydrogen isotopes and hence their high pressure, but these works do not allow explaining some of the structures present at the solid phase change effect of increased pressure. By means of simulation with first principles methods and Quantum Molecular Dynamics, we compare the structural difference of solid molecular hydrogen pure and solid molecular hydrogen with beryllium, watching beryllium inclusion in solid hydrogen matrix, we obtain several differences in mechanical properties, in particular elastic constants. For C11 the difference between hydrogen and hydrogen with beryllium is 37.56%. This may produce a non-uniform initial compression and decreased efficiency of ignition.

  10. Measurement of the ultracold neutron loss coefficient in beryllium powder

    International Nuclear Information System (INIS)

    The ultracold neutron (UCN) reflection from beryllium powder at different slab thicknesses and different packing densities is measured. The reduced UCN loss coefficient η=(1.75±0.35)x10-4 for thermally untreated beryllium is extracted from experimental data. The formerly obtained experimental results on UCN reflection from beryllium after high temperature annealing are reconsidered. The loss coefficient η at room temperature in this case is obtained to be (6.4±2.5)x10-5, which is an order of magnitude higher than the theoretical one. The extraction of the loss coefficient from the experimental data is based on the modified diffusion theory where albedo reflection depends on packing density

  11. Estimation of beryllium ground state energy by Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kabir, K. M. Ariful [Department of Physical Sciences, School of Engineering and Computer Science, Independent University, Bangladesh (IUB) Dhaka (Bangladesh); Halder, Amal [Department of Mathematics, University of Dhaka Dhaka (Bangladesh)

    2015-05-15

    Quantum Monte Carlo method represent a powerful and broadly applicable computational tool for finding very accurate solution of the stationary Schrödinger equation for atoms, molecules, solids and a variety of model systems. Using variational Monte Carlo method we have calculated the ground state energy of the Beryllium atom. Our calculation are based on using a modified four parameters trial wave function which leads to good result comparing with the few parameters trial wave functions presented before. Based on random Numbers we can generate a large sample of electron locations to estimate the ground state energy of Beryllium. Our calculation gives good estimation for the ground state energy of the Beryllium atom comparing with the corresponding exact data.

  12. Elemental composition in sealed plutonium–beryllium neutron sources

    International Nuclear Information System (INIS)

    Five sealed plutonium–beryllium (PuBe) neutron sources from various manufacturers were disassembled. Destructive chemical analyses for recovered PuBe materials were conducted for disposition purposes. A dissolution method for PuBe alloys was developed for quantitative plutonium (Pu) and beryllium (Be) assay. Quantitation of Be and trace elements was performed using plasma based spectroscopic instruments, namely inductively coupled plasma mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES). Pu assay was accomplished by an electrochemical method. Variations in trace elemental contents among the five PuBe sources are discussed. - Highlights: • A destructive chemical analysis of the PuBe neutron sources includes the solubilization and digestion of the PuBe alloy material. • Plutonium was assayed by an electrochemical method. • Beryllium assay and trace elemental contents were determined by ICP instruments. • A large variation in trace elemental composition was observed among the five PuBe source materials

  13. Extraction of beryllium sulfate by a long chain amine

    International Nuclear Information System (INIS)

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author)

  14. Photochemical Behavior of Beryllium Complexes with Subporphyrazines and Subphthalocyanines.

    Science.gov (United States)

    Montero-Campillo, M Merced; Lamsabhi, Al Mokhtar; Mó, Otilia; Yáñez, Manuel

    2016-07-14

    Structures of beryllium subphthalocyanines and beryllium subporphyrazines complexes with different substituents are explored for the first time. Their photochemical properties are studied using time-dependent density functional theory calculations and compared to boron-related compounds for which their photochemical activity is already known. These beryllium compounds were found to be thermodynamically stable in a vacuum and present features similar to those of boron-containing analogues, although the nature of bonding between the cation and the macrocycle presents subtle differences. Most important contributions to the main peak in the Q-band region arise from HOMO to LUMO transitions in the case of subphthalocyanines and alkyl subporphyrazine complexes, whereas a mixture of that contribution and a HOMO-2 to LUMO contribution are present in the case of thioalkyl subporphyrazines. The absorption in the visible region could make these candidates suitable for photochemical devices if combined with appropriate donor groups. PMID:26812068

  15. Synthesis of New Pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (PCU) Cyanosilylated Derivatives Using Sulphated Zirconia and Hydrotalcite as Catalysts in Microwave-Assisted Reactions under Solvent Free Conditions

    OpenAIRE

    Juan Navarrete-Bolaños; Rubén Gaviño-Ramírez; Eduardo González-Zamora; Leticia Lomas-Romero; Guillermo E. Negrón-Silva; Deyanira Angeles-Beltrán; Laura Nadxieli Palacios-Grijalva; Nahí Adriana Guerra-Navarro

    2011-01-01

    A comparison was made of the effectiveness of the functionalization reactions of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (PCU) using sulphated zirconia in protection-deprotection reactions and Mg/Al hydrotalcite in a cyanosilylation reaction, under classical thermal conditions and imposing microwave radiation; improved yields and reaction times were considered.

  16. Synthesis of New Pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (PCU Cyanosilylated Derivatives Using Sulphated Zirconia and Hydrotalcite as Catalysts in Microwave-Assisted Reactions under Solvent Free Conditions

    Directory of Open Access Journals (Sweden)

    Juan Navarrete-Bolaños

    2011-08-01

    Full Text Available A comparison was made of the effectiveness of the functionalization reactions of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (PCU using sulphated zirconia in protection-deprotection reactions and Mg/Al hydrotalcite in a cyanosilylation reaction, under classical thermal conditions and imposing microwave radiation; improved yields and reaction times were considered.

  17. Copper Causes Regiospecific Formation of C4F8-Containing Six-Membered Rings and their Defluorination/Aromatization to C4F4-Containing Rings in Triphenylene/1,4-C4F8I2 Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Rippy, Kerry C.; Bukovsky, Eric V.; Clikeman, Tyler T.; Chen, Yu-Sheng; Hou, Gao-Lei; Wang, Xue B.; Popov, Alexey; Boltalina, Olga V.; Strauss, Steven H.

    2016-01-18

    The presence of Cu in reactions of triphenylene (TRPH) and 1,4-C4F8I2 at 360 °C led to regiospecific substitution of TRPH ortho C(β) atoms to form C4F8-containing rings, completely suppressing substitution on C(α) atoms. In addition, Cu caused selective reductive-defluorination/aromatization (RD/A) to form C4F4- containing aromatic rings. Without Cu, the reactions of TRPH and 1,4- C4F8I2 were not regiospecific and no RD/A was observed. These results, supported by DFT calculations, are the first examples of Cupromoted (i) regiospecific perfluoroannulation, (ii) preparative C–F activation, and (iii) RD/A. HPLC-purified products were characterized by X-ray diffraction, low-temperature PES, and 1H/19F NMR.

  18. Study of 9Be (d,p0)10Be and 9Be(d,t0)8Be reactions between 0.24 and 3.8 MeV

    International Nuclear Information System (INIS)

    This research thesis addresses the precise study of the mechanism of direct interaction within the frame of the stripping and pick-up theory of distorted waves, and of the involved parameters for the 9Be (d,p0)10Be and 9Be(d,t0)8Be reactions between 0.24 and 3.8 MeV. After a description of the arrangements and methods used to obtain experimental angular distributions on different energy ranges (0.24, 0.7-3.0, and 3.4-3.8 MeV), the author recalls the formalism of the theory of distorted waves within the Born approximation. The author then presents the experimental and theoretical results: angular distributions and excitation functions as far as experimental results are concerned, and deuton elastic scattering and analysis of both reactions as far as theoretical results are concerned. He discusses their correlation

  19. CHAPTER 7. BERYLLIUM ANALYSIS BY NON-PLASMA BASED METHODS

    Energy Technology Data Exchange (ETDEWEB)

    Ekechukwu, A

    2009-04-20

    The most common method of analysis for beryllium is inductively coupled plasma atomic emission spectrometry (ICP-AES). This method, along with inductively coupled plasma mass spectrometry (ICP-MS), is discussed in Chapter 6. However, other methods exist and have been used for different applications. These methods include spectroscopic, chromatographic, colorimetric, and electrochemical. This chapter provides an overview of beryllium analysis methods other than plasma spectrometry (inductively coupled plasma atomic emission spectrometry or mass spectrometry). The basic methods, detection limits and interferences are described. Specific applications from the literature are also presented.

  20. The uses and adverse effects of beryllium on health

    DEFF Research Database (Denmark)

    Cooper, Ross G.; Harrison, Adrian Paul

    2009-01-01

    the current review for selecting articles were adopted from proposed criteria in The International Classification of Functioning, Disability, and Health. Articles were classified based on acute and chronic exposure and toxicity of beryllium. Results: The proportions of utilized and nonutilized...... articles were published in sources unobtainable through requests at the British Library, and some had no impact factor and were excluded. Conclusion: Beryllium has some useful but undoubtedly harmful effects on health and well-being. Measures needed to be taken to prevent hazardous exposure to this element...

  1. Method for removal of beryllium contamination from an article

    Science.gov (United States)

    Simandl, Ronald F.; Hollenbeck, Scott M.

    2012-12-25

    A method of removal of beryllium contamination from an article is disclosed. The method typically involves dissolving polyisobutylene in a solvent such as hexane to form a tackifier solution, soaking the substrate in the tackifier to produce a preform, and then drying the preform to produce the cleaning medium. The cleaning media are typically used dry, without any liquid cleaning agent to rub the surface of the article and remove the beryllium contamination below a non-detect level. In some embodiments no detectible residue is transferred from the cleaning wipe to the article as a result of the cleaning process.

  2. Radiation Damage of Beryllium Reflector for Research Reactor Application

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Suk Hoon [Korea Atomic Energy Research Institute Daejeon (Korea, Republic of)

    2013-07-01

    Beryllium is considered as a reflector material for the research reactor. The neutron fluence results in significant damage of material structure and corresponding degradation of physical.mechanical properties. In this study, the proton radiation damage of the beryllium grade manufactured by hot extrusion was investigated to emulate the effect of neutron radiation. The samples were irradiated by protons at room temperature; the acceleration voltage, and the proton amounts were 120keV, and 2.0 Χ 10{sup 18} ions/cm{sup 2}, respectively. The neutron irradiation experiment also have been conducted in HANARO, their results will be discussed in terms of swelling, and microstructure evolution.

  3. Collisional quenching reaction rate coefficients of N2 (A3Σu+) by C2F6 and C3F8

    Science.gov (United States)

    Suzuki, Susumu; Kuboaki, Masaru; Itoh, Haruo

    2015-09-01

    The collisional quenching reaction rate coefficient of N2 (A3Σu+) by various air pollutant gases were determined from the measurement of the effective lifetime of N2 (A3Σu+) in pure N2 (5-nine) with a small amount of air pollutant gases as an admixture. Derivation of the rate coefficient was performed the waveform analysis of the transient ionization current after turning off the UV light in the Townsend discharge. In this paper, we report that the obtained collisional quenching reaction rate coefficients of N2 (A3Σu+) by C2F6 and C3F8 are (2.3 +/- 1.8) × 10-15 cm3/s and (1.6 +/- 0.8) × 10-14 cm3/s, respectively. Furthermore, we investigate the relationship between the rate coefficient and the mass number of their quenching molecular gases. Firstly, it is confirmed that the rate coefficient take large value with an increase in the mass number of the quenching gases. Secondly, if H atom is included in the gas molecules such as CH4, C2F6 and C3F8 the rate coefficient take large value, but if the molecules including F atom such as C2F6 and C3F8 instead of H atom in this study, more smaller values of the collisional quenching reaction rate coefficient are observed.

  4. 7Li(p-arrow-right,π+)8Li and 7Li(p-arrow-right,π-)8B reactions at T/sub p/ = 200 MeV

    International Nuclear Information System (INIS)

    Angular distributions of the cross sections and analyzing powers for the 7Li(p,π/sup +- /) reactions leading to the ground and first two excited states of the isobaric analog final nuclei 8Li and 8B have been measured at T/sub p/ = 200.4 MeV and 199.2 MeV, respectively. The (p,π+) cross sections are an order of magnitude larger than those of the (p,π-) reaction and exhibit a much stronger angular dependence. The (p,π+) analyzing power patterns are essentially state independent and similar to that of the elementary pp→dπ+ reaction near threshold. The analyzing power angular distribution for the 7Li(p,π-) 8B(2.32 MeV, 3+) transition exhibits a ''signature'' characteristic of (p,π-) transitions to stretched high-spin two-particle one-hole final states, which is distinctly different from the pattern observed for transitions to low-spin final states. The differences between the two reactions are interpreted in terms of the dynamics of the elementary pp→dπ+ and pn→ppπ- processes

  5. Structural basis of chronic beryllium disease: linking allergic hypersensitivity and autoimmunity.

    Science.gov (United States)

    Clayton, Gina M; Wang, Yang; Crawford, Frances; Novikov, Andrey; Wimberly, Brian T; Kieft, Jeffrey S; Falta, Michael T; Bowerman, Natalie A; Marrack, Philippa; Fontenot, Andrew P; Dai, Shaodong; Kappler, John W

    2014-07-01

    T-cell-mediated hypersensitivity to metal cations is common in humans. How the T cell antigen receptor (TCR) recognizes these cations bound to a major histocompatibility complex (MHC) protein and self-peptide is unknown. Individuals carrying the MHCII allele, HLA-DP2, are at risk for chronic beryllium disease (CBD), a debilitating inflammatory lung condition caused by the reaction of CD4 T cells to inhaled beryllium. Here, we show that the T cell ligand is created when a Be(2+) cation becomes buried in an HLA-DP2/peptide complex, where it is coordinated by both MHC and peptide acidic amino acids. Surprisingly, the TCR does not interact with the Be(2+) itself, but rather with surface changes induced by the firmly bound Be(2+) and an accompanying Na(+) cation. Thus, CBD, by creating a new antigen by indirectly modifying the structure of preexisting self MHC-peptide complex, lies on the border between allergic hypersensitivity and autoimmunity. PMID:24995984

  6. Study of the diffusion of iron, of silver and of carbon in beryllium using radioactive tracers

    International Nuclear Information System (INIS)

    A study has been made of the diffusion of radioactive iron and silver tracers in beryllium. The following values have been found. DFe = 0.53 exp - [51800 / RT], DAg = 62 exp - [46100 / RT]. The values for iron are in good agreement with those found previously for chemical diffusion. A comparison of the diffusion coefficients for iron, silver and nickel shows that the diffusion rate increases with increasing solute atom radius. The existence has been shown of diffusion anisotropy for silver; it has been studied quantitatively on monocrystals. It is found that: Dparallel 0.41 exp - [39100 / RT], Dperpendicular = 1.98 exp - [45700 / RT]. The anisotropy decreases as the temperature increases. The silver diffuses more rapidly along the C axis than in the base plane. This result cannot be explained in terms of the model proposed for the diffusion of foreign atoms in solution in zinc. A greater number of experiments is required before a model can be put forward. An attempt has also been made to determine the diffusion coefficients of carbon in beryllium by treatment in an atmosphere of acetylene marked with C-14. Diffusion coefficients have been obtained but these should not be considered to be very significant since a chemical reaction occurs at the surface of the samples. (author)

  7. Radicals in Transition Metal Catalyzed Reactions? Transition Metal Catalyzed Radical Reactions? - A Fruitful Interplay Anyway. Part 2. Radical Catalysis by Group 8 to Group 9 Elements

    Czech Academy of Sciences Publication Activity Database

    Jahn, Ullrich

    Heidelberg : Springer, 2012 - (Heinrich, M.; Gansäuer, A.), s. 191-322 ISBN 978-3-642-28122-8. - (Topic in Current Chemistry. 320) R&D Projects: GA ČR GA203/09/1936 Institutional research plan: CEZ:AV0Z40550506 Keywords : catalysis * cross-coupling * cyclization * electron transfer * radicals * transition metals * addition Subject RIV: CC - Organic Chemistry

  8. 8-Membered-ring Transition States of Water Assisted Reactions in Sub-and Super-critical Water

    Institute of Scientific and Technical Information of China (English)

    Kazuya; Kobiro; Pengyu; Wang

    2007-01-01

    1 Results Sub-and super-critical water is an attractive reaction medium for organic transformation because of their unique properties such as low viscosity,high density,low polarity,high solubility to organic compounds,and,of course,the greenness of the medium[1-3]. We report herein some unique reactions of unsaturated compounds in sub-and super-critical water.When allylbenzene was treated in supercritical water (SCW: 380 ℃,10 min,water density=0.35 g/mL),double bond migrated to give a mixture of allylb...

  9. Beryllium Health and Safety Committee Data Reporting Task Force White Paper #2 -- Uses of Uncensored Data

    Energy Technology Data Exchange (ETDEWEB)

    MacQueen, D H

    2007-10-10

    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: (1) reduce the number of workers currently exposed to beryllium in the course of their work at DOE facilities managed by DOE or its contractors; (2) minimize the levels of, and potential for, exposure to beryllium; and (3) establish medical surveillance requirements to ensure early detection of the disease. On January 4, 2001, DOE issued DOE G 440.1-7A, Implementation Guide for use with 10 CFR 850, Chronic Beryllium Disease Prevention Program, to assist line managers in meeting their responsibilities for implementing the CBDPP. That guide describes methods and techniques that DOE considers acceptable in complying with the Rule. In 2005 a draft DOE Technical Standard ''Management of Items and Areas Containing Low Levels of Beryllium'' (SAFT 0103; hereafter referred to as the ''TS'') was circulated for comment (http://www.hss.energy.gov/NuclearSafety/techstds/tsdrafts/saft-0103.pdf). DOE technical standards are voluntary consensus standards developed when industry standards do not exist (see http://www.hss.energy.gov/NuclearSafety/techstds/index.html for more information). DOE does not require its field elements to implement DOE technical standards, but field elements may choose to adopt these standards to meet specific needs. This beryllium TS is intended to provide best practices and lessons learned for manageing items and areas that contain low levels of beryllium, which has been a costly and technically challenging component of CBDPPs. The TS is also intended to provide guidance for determining if the Rule's housekeeping and release criteria are met. On challenge the TS addressed was the statistical interpretation of data sets with non-detected results, a topic for which no strong consensus exists. Among the many comments on the draft

  10. 4π studies of the 1.8 endash 4.8 GeV 3He+natAg, 197Au reactions. II. Multifragmentation

    International Nuclear Information System (INIS)

    Multifragmentation of natAg and 197Au nuclei induced by 1.8 endash 4.8 GeV 3He ions has been studied with the Indiana Silicon Sphere 4π detector array. Rapidity, moving source, and sphericity-coplanarity analyses are consistent with near-simultaneous emission from a source in approximate kinetic equilibrium. For the most dissipative collisions, the spectral peaks are broadened and shifted to very low energies, indicative of emission from an extended nuclear system with ρ/ρ0∼1/3. Predictions of an intranuclear cascade/expanding, emitting source model compare well with experimental multiplicity distributions and the evolution of fragment spectral shapes. copyright 1996 The American Physical Society

  11. Fluorometric determination of beryllium with salicylidene-2-aminophenol in the presence of ethylenediamine

    International Nuclear Information System (INIS)

    This procedure can be carried out in aqueous or water-methanol medium. In aqueous media, the Be-salicylidene-2-aminophenol (SAPH) complex is quantitatively formed in the range of pH 8.1--8.6. This complex has an excitation max. at 345 nm and fluorescence max. at 440 nm. The fluorescence intensity is enhanced remarkably under the addition of ethylene-diamine (en) as a buffer with 1 ml of 0.04 % SAPH, 0.005--4 μg Be/25 ml can be determined in the presence of 1 ml of en. The relative standard deviation(R.S.D.) was 3.5 % for 0.019 μg beryllium. In the water-methanol media, the formation of the complex at pH 10 is highly reproducible. The complex is stood for 25 min before measurements. Here, 0.01--4 μg Be/25 ml can be determined. The R.S.D. was the same as the case of aqueous media. The Be complex was more stable in the water-methanol media than in the aqueous media. The fluorescence of the complex formed in the mixed medium (H2O:MeOH=2:3) keeps the intensity constant at least for 30 min. Although cobalt, chromium, and others interfere with the determination, they can be masked with EDTA. The proposed procedure was applied to the analysis of beryllium-copper alloy. (author)

  12. 8-MOP的光敏反应对DNA特定位置的致损伤作用%Photosensitive reaction of 8-MOP induce objective DNA damage

    Institute of Scientific and Technical Information of China (English)

    熊鸿燕; 王思雄; 胡小兵; 徐斌; 陈惠孙

    2001-01-01

    目的:探讨末端标记8-甲氧基补骨脂素(8-MOP)的三螺旋结构寡核苷酸(TFO)对鸭乙肝病毒(DHBV)-DNA X/C区一目标基因的特异结合及定位损伤作用.材料方法:在一定条件下,将人工合成的3'末端标记有8-MOP的TFO与目标双链基因片断反应,用电泳转移杂交印迹和PCR法观察设计的复合物(TFo-P)对目标基因的结合以及在长波紫外线(UVA)的照射下8-MOP所致DNA交联及引起的PCR扩增阻止效应.结果:所设计合成的TFO-P能与细胞外DHBV-DNA的目标基因双链直接结合,随TFO-P含量的增加,TFO-P与目标双链形成的三聚体分子的产量明显增加;TFO-P与目标基因的反应物经一定剂量的320~380nmUVA照射后,目标序列的PCR扩增出现阻断现象.结论TFO-P能直接与目标DNA特异结合,形成三聚体产物,在UVA的进一步作用下,TFO-P能在目标序列的设定位置发生光敏反应,使DNA形成共价交联结构.

  13. Status of the beryllium replacement project

    International Nuclear Information System (INIS)

    Currently, beryllium (Be) is used as the filler metal for brazing appendages on the sheaths of CANDU® fuel elements. Because of its toxicity, occupational exposure limits for Be are being reduced to very low levels, resulting in significant challenges to CANDU® fuel fabricators. The CANDU® Owners Group (COG) initiated a test program to identify a filler material to replace Be and confirm that the brazed joints meet the established technical requirements for CANDU® fuel. Together with eliminating health risks associated with the use of Be, the industry needs to be assured that continuation of fuel supply remains unaffected and that fuel fabrication processes continue to comply with health and safety standards. A literature survey of studies on brazing and joining of Zircaloy identified potential filler materials that can meet or exceed existing design requirements of the brazed joint, including the required mechanical, microstructural, corrosion resistance, and irradiation properties equivalent to those obtained with Be as braze material. Candidate materials were evaluated against several criteria, including manufacturability, melting point, wettability, mechanical properties, corrosion resistance, effect on neutron economy, potential activation products, and interaction with fuel channels and other related disciplines. This exercise resulted in a list of promising candidate materials that were recommended for the first phase of testing. These materials include stainless steel (304 or 316), Al-Si, Ni-P, and Zr-Mn alloys. To allow a CANDU® utility have sufficient confidence in considering implementation of a different braze filler material, a Be Replacement Test Program, involving out-reactor and in-reactor tests, is being undertaken as a collaborative endeavour by the Canadian nuclear industry. The out-reactor tests consist of: a constructability assessment to determine the material’s suitability with current fuel manufacturing methods; evaluation of

  14. Irradiation effects on aluminium and beryllium

    International Nuclear Information System (INIS)

    .6%. Besides, due to the effects of embrittlement and swelling induced by irradiation, the HFR beryllium reflector elements had to be replaced after more than 25 years of operation. Operational and practical experiences with these reflector elements are commented, as well as main engineering features of the new reflector elements: upper-end fittings of both filler element and insert in stainless steel, no radially drilled holes and no roll pins

  15. Involvement of DEG5 and DEG8 proteases in the turnover of the photosystem II reaction center D1 protein under heat stress in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    SUN XuWu; WANG LiYuan; ZHANG LiXin

    2007-01-01

    Deg5,deg8 and the double mutant,deg5deg8 of Arabidopsis thaliana were used to study the physiological role of the DEG proteases in the repair cycle of photosystem II (PSII) under heat stress. PSII activity in deg mutants showed increased sensitivity to heat stress,and the extent of this effect was greater in the double mutant,deg5deg8,than in the single mutants,deg5 and deg8. Degradation of the D1 protein was slower in the mutants than in the WT plants. Furthermore,the levels of other PSII reaction center proteins tested remained relatively stable in the mutant and WT plants following high-temperature treatment. Thus,our results indicate that DEG5 and DEG8 may have synergistic function in degradation of D1 protein under heat stress.

  16. Tritium release from beryllium discs and lithium ceramics irradiated in the SIBELIUS experiment

    International Nuclear Information System (INIS)

    The SIBELIUS experiment was designed to obtain information on the compatibility between beryllium and ceramics, as well as beryllium and steel, in a neutron environment. This experiment comprised irradiation of eight capsules, seven of which were independently purged with a He/0.1% H2 gas mixture. Four capsules were used to examine beryllium/ceramic (Li2O, LiAlO2, Li4SiO4, and Li2ZrO3) and beryllium/steel (Types 316L and 1.4914) compacts. Isothermal anneal experiments have been run on representative beryllium and ceramic disks from each of the four capsules at 550 degrees C to 850 degrees C in steps of 100 degrees C. The results indicate that tritium release from the beryllium did not exhibit burst release behavior, as previously reported, but rather a progressive release with increasing temperature. Generally, ∼99% of the tritium was released by 850 degrees C. Tritium release from the ceramic discs was quite similar to the behavior shown in other dynamic tritium release experiments on lithium ceramics. The tritium content in beryllium discs adjacent to a steel sample was found to be significantly lower than that found in a beryllium disc adjacent to a ceramic sample. Recoil of tritium from the ceramic into the beryllium appears to be the source of tritium entering the beryllium, probably residing in the beryllium oxide layer

  17. Beryllium solubility in occupational airborne particles: Sequential extraction procedure and workplace application.

    Science.gov (United States)

    Rousset, Davy; Durand, Thibaut

    2016-01-01

    Modification of an existing sequential extraction procedure for inorganic beryllium species in the particulate matter of emissions and in working areas is described. The speciation protocol was adapted to carry out beryllium extraction in closed-face cassette sampler to take wall deposits into account. This four-step sequential extraction procedure aims to separate beryllium salts, metal, and oxides from airborne particles for individual quantification. Characterization of the beryllium species according to their solubility in air samples may provide information relative to toxicity, which is potentially related to the different beryllium chemical forms. Beryllium salts (BeF(2), BeSO(4)), metallic beryllium (Bemet), and beryllium oxide (BeO) were first individually tested, and then tested in mixtures. Cassettes were spiked with these species and recovery rates were calculated. Quantitative analyses with matched matrix were performed using inductively coupled plasma mass spectrometry (ICP-MS). Method Detection Limits (MDLs) were calculated for the four matrices used in the different extraction steps. In all cases, the MDL was below 4.2 ng/sample. This method is appropriate for assessing occupational exposure to beryllium as the lowest recommended threshold limit values are 0.01 µg.m(-3) in France([) (1) (]) and 0.05 µg.m(-3) in the USA.([ 2 ]) The protocol was then tested on samples from French factories where occupational beryllium exposure was suspected. Beryllium solubility was variable between factories and among the same workplace between different tasks. PMID:26327570

  18. Comparison of elevated temperature properties of HIP'd impact ground beryllium (S-65-H) and HIP'd gas atomized (GA) beryllium

    International Nuclear Information System (INIS)

    Fusion designers have been limited to simple tensile properties and physical properties for modern beryllium grades. The work reported here expands the elevated temperature database to more complicated mechanical tests. The elevated temperature (ambient to 648 C) thermomechanical properties of two beryllium grades made by hot isostatic pressing (HIP) are compared: S-65H (made from impact ground powder) and GA (made from gas atomized powder). Successful measurements of elevated temperature smooth and notched fatigue were made for the first time on modern beryllium grades. Valid beryllium KIC fracture toughness results were obtained for the first time at temperatures above room temperature. Elevated temperature creep, and tensile are also presented. (orig.)

  19. Synthesis of Y3Ba5Cu8O18 superconductor powder by auto-combustion reaction: Effects of citrate-nitrate ratio

    International Nuclear Information System (INIS)

    In this experiment, nanocrystalline Y3Ba5Cu8O18 superconductor powder was prepared by citrate-nitrate auto-combustion reaction. A series of Y3Ba5Cu8O18 precursor gels with different citrate-nitrate ratio ranged from 0.3 to 1.0 have been prepared by varying the amount of citric acid added. The auto-combustion reaction during drying process transformed the precursor gels into ashes powder that upon calcinations at 900 °C yield Y3Ba5Cu8O18 nanocrystalline powders. The TG/DTA analysis reveals that the precursor gels with 0.3 ⩽ c/n 3Ba5Cu8O18 calcined powder prepared from c/n = 0.7 precursor gels has got the orthorhombic structure with smallest particle size (∼10 nm) compared to the rest of the batches. Samples with c/n = 0.5 and 0.7 appeared in this work to be electrically superconducting at temperature above 100 K as measured using standard four-probe technique. This emphasized on maintaining a stoichiometric or near stoichiometric reaction for the analysis.

  20. Reducing the cost of S-65C grade beryllium for ITER first wall applications

    International Nuclear Information System (INIS)

    Beryllium is the current material of choice for plasma-facing components in ITER. The present design is for 10 mm thick beryllium tiles bonded to an actively cooled copper substrate. Brush Wellman grade S65C beryllium is preferred grade off beryllium for these tiles. S65C has the best resistance to low-cycle thermal fatigue than any other beryllium grad in the world. S65C grade beryllium has been successfully deployed in fusion reactors for more than two decades, most recently in the JET reactor. This paper will detail a supply chain to produce the most cost-effective S65C plasma facing components for ITER. This paper will also propose some future work too demonstrate the best technology for bonding beryllium to copper. (author)

  1. TEM study of impurity segregations in beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Klimenkov, M., E-mail: michael.klimenkov@kit.edu [Institute for Applied Materials – Applied Materials Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Chakin, V.; Moeslang, A. [Institute for Applied Materials – Applied Materials Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Rolli, R. [Institute for Applied Materials – Materials and Biomechanics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2014-12-15

    Beryllium is planned to be used as a neutron multiplier in the Helium-cooled Pebble Bed European concept of a breeding blanket of demonstration power reactor DEMO. In order to evaluate the irradiation performance, individual pebbles and constrained pebble beds were neutron-irradiated at temperatures typical of fusion blankets. Beryllium pebbles 1 mm in diameter produced by the rotating electrode method were subjected to a TEM study before and after irradiation at High Flux Reactor, Petten, Netherlands at 861 K. The grain size varied in a wide range from sub-micron size up to several tens of micrometers, which indicated formation bimodal grain size distribution. Based on the application of combined electron energy loss spectroscopy and energy dispersive X-ray spectroscopy methods, we suggest that impurity precipitates play an important role in controlling the mechanical properties of beryllium. The impurity elements were present in beryllium at a sub-percent concentration form beryllide particles of a complex (Fe/Al/Mn/Cr)B composition. These particles are often ordered along dislocations lines, forming several micron-long chains. It can be suggested that fracture surfaces often extended along these chains in irradiated material.

  2. Beryllium abundances in stars with planets:Extending the sample

    CERN Document Server

    Gálvez-Ortiz, M C; Hernández, J I González; Israelian, G; Santos, N C; Rebolo, R; Ecuvillon, A

    2011-01-01

    Context: Chemical abundances of light elements as beryllium in planet-host stars allow us to study the planet formation scenarios and/or investigate possible surface pollution processes. Aims: We present here an extension of previous beryllium abundance studies. The complete sample consists of 70 stars hosting planets and 30 stars without known planetary companions. The aim of this paper is to further assess the trends found in previous studies with less number of objects. This will provide more information on the processes of depletion and mixing of light elements in the interior of late type stars, and will provide possible explanations for the abundance differences between stars that host planets and "single" stars. Methods: Using high resolution UVES spectra, we measure beryllium abundances of 26 stars that host planets and 1 "single" star mainly using the \\lambda 3131.065 A Be II line, by fitting synthetic spectra to the observational data. We also compile beryllium abundance measurements of 44 stars hos...

  3. TEM study of impurity segregations in beryllium pebbles

    Science.gov (United States)

    Klimenkov, M.; Chakin, V.; Moeslang, A.; Rolli, R.

    2014-12-01

    Beryllium is planned to be used as a neutron multiplier in the Helium-cooled Pebble Bed European concept of a breeding blanket of demonstration power reactor DEMO. In order to evaluate the irradiation performance, individual pebbles and constrained pebble beds were neutron-irradiated at temperatures typical of fusion blankets. Beryllium pebbles 1 mm in diameter produced by the rotating electrode method were subjected to a TEM study before and after irradiation at High Flux Reactor, Petten, Netherlands at 861 K. The grain size varied in a wide range from sub-micron size up to several tens of micrometers, which indicated formation bimodal grain size distribution. Based on the application of combined electron energy loss spectroscopy and energy dispersive X-ray spectroscopy methods, we suggest that impurity precipitates play an important role in controlling the mechanical properties of beryllium. The impurity elements were present in beryllium at a sub-percent concentration form beryllide particles of a complex (Fe/Al/Mn/Cr)B composition. These particles are often ordered along dislocations lines, forming several micron-long chains. It can be suggested that fracture surfaces often extended along these chains in irradiated material.

  4. Influence of impurities in Beryllium on tritium breeding ratio

    International Nuclear Information System (INIS)

    Several neutronics experiments simulating fusion blankets have been conducted with 14 MeV neutron source to assess the reliability of nuclear analysis codes. However, the analyses have not always presented good agreements so far between calculated and measured tritium production rates. One of the reasons was considered as impurities in beryllium which has negligibly small neutron absorption cross section in low energy range. Chemical compositions of beryllium were analyzed by Inductively Coupled Plasma (ICP) method, and a pulsed neutron decay experiment discovered that the macroscopic neutron absorption cross section for beryllium medium may be about 30% larger than the value calculated by the data specified by manufacturing company. The influence of the impurities on the calculations was studied on the basis of the fusion DEMO-reactor blanket design. As a result of the study, it was made clear that the impurities affect the local tritium production rates when the size of beryllium medium is more than 20-30 mean free paths (30-40 cm) in thickness. In case of some blanket designs that meet the above condition, the effect on tritium breeding ratio may become as large as about 4%. (author)

  5. Thermal cycling tests of actively cooled beryllium copper joints

    International Nuclear Information System (INIS)

    Screening tests (steady state heating) and thermal fatigue tests with several kinds of beryllium-copper joints have been performed in an electron beam facility. Joining techniques under investigation were brazing with silver containing and silver-free braze materials, hot isostatic pressing (HIP) and diffusion bonding (hot pressing). Best thermal fatigue performance was found for the brazed samples. (author)

  6. Extraction of lead and beryllium from a firing site soil

    International Nuclear Information System (INIS)

    The Dual Axis Radiographic Hydrodynamic Test (DARHT) program is being implemented at LANL to conduct tests for evaluating the stability of the nation's aging nuclear stockpile. In order to reduce impact on the environment, containment of the non-fissile explosives tests is being phased in. The resulting shot debris can contain a mix of depleted uranium, lead, and beryllium. We are developing a treatment scheme to separate the radioactive and RCRA-hazardous components in order to recover the uranium, re-use some materials in future shots, and minimize waste for disposal. Our experience using a proprietary water soluble polymer to extract lead from contaminated soil to below TCLP levels has been extended to a surrogate soil from an open-air firing site that contains both lead and beryllium. Results for lead removal from this soil by dendrimers and molecular chelators will also be shown. Because of the potentially severe inhalation hazard associated with beryllium, the fate of this metal in our treatment scheme has been investigated, as well as extraction of beryllium using a variety of chemical agents

  7. Correlation of acoustic emission and dislocation damping in beryllium

    International Nuclear Information System (INIS)

    In a study of the acoustic emission generated in beryllium during tensile deformation, there is substantial evidence showing that the burst rate peak at yield is due to the generation of new dislocations and the burst rate peak at higher strains is due to the breakaway of dislocation line segments from deformation produce pins

  8. Biogeochemistry of beryllium in a forested catchment, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Skřivan, Petr; Vach, Marek; Filippi, Michal

    Edinburg : University of Edinburg, 2003. s. 94. [International Symposium on Environmental Geochemistry.. 07.09.2003-11.09.2003, Edinburg] R&D Projects: GA AV ČR IAB3013203 Institutional research plan: CEZ:AV0Z3013912 Keywords : biogeochemistry * experimental catchment * beryllium Subject RIV: DD - Geochemistry

  9. Thermal cycling tests of actively cooled beryllium copper joints

    Energy Technology Data Exchange (ETDEWEB)

    Roedig, M.; Duwe, R.; Linke, J.; Schuster, A.; Wiechers, B. [Forschungszentrum Juelich GmbH (Germany)

    1998-01-01

    Screening tests (steady state heating) and thermal fatigue tests with several kinds of beryllium-copper joints have been performed in an electron beam facility. Joining techniques under investigation were brazing with silver containing and silver-free braze materials, hot isostatic pressing (HIP) and diffusion bonding (hot pressing). Best thermal fatigue performance was found for the brazed samples. (author)

  10. Beryllium Wipe Sampling (differing methods - differing exposure potentials)

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, Kent

    2005-03-09

    This research compared three wipe sampling techniques currently used to test for beryllium contamination on room and equipment surfaces in Department of Energy facilities. Efficiencies of removal of beryllium contamination from typical painted surfaces were tested by wipe sampling without a wetting agent, with water-moistened wipe materials, and by methanol-moistened wipes. Analysis indicated that methanol-moistened wipe sampling removed about twice as much beryllium/oil-film surface contamination as water-moistened wipes, which removed about twice as much residue as dry wipes. Criteria at 10 CFR 850.30 and .31 were established on unspecified wipe sampling method(s). The results of this study reveal a need to identify criteria-setting method and equivalency factors. As facilities change wipe sampling methods among the three compared in this study, these results may be useful for approximate correlations. Accurate decontamination decision-making depends on the selection of appropriate wetting agents for the types of residues and surfaces. Evidence for beryllium sensitization via skin exposure argues in favor of wipe sampling with wetting agents that provide enhanced removal efficiency such as methanol when surface contamination includes oil mist residue.

  11. Identification of an abnormal beryllium lymphocyte proliferation test

    International Nuclear Information System (INIS)

    The potential hazards from exposure to beryllium or beryllium compounds in the workplace were first reported in the 1930s. The tritiated thymidine beryllium lymphocyte proliferation test (BeLPT) is an in vitro blood test that is widely used to screen beryllium exposed workers in the nuclear industry for sensitivity to beryllium. The clinical significance of the BeLPT was described and a standard protocol was developed in the late 1980s. Cell proliferation is measured by the incorporation of tritiated thymidine into dividing cells on two culture dates and using three concentrations of beryllium sulfate. Results are expressed as a 'stimulation index' (SI) which is the ratio of the amount of tritiated thymidine (measured by beta counts) in the simulated cells divided by the counts for the unstimulated cells on the same culture day. Several statistical methods for use in the routine analysis of the BeLPT were proposed in the early 1990s. The least absolute values (LAV) method was recommended for routine analysis of the BeLPT. This report further evaluates the LAV method using new data, and proposes a new method for identification of an abnormal or borderline test. This new statistical-biological positive (SBP) method reflects the clinical judgment that: (i) at least two SIs show a 'positive' response to beryllium; and (ii) that the maximum of the six SIs must exceed a cut-point that is determined from a reference data set of normal individuals whose blood has been tested by the same method in the same serum. The new data is from the Y-12 National Security Complex in Oak Ridge (Y-12) and consists of 1080 workers and 33 non-exposed control BeLPTs (all tested in the same serum). Graphical results are presented to explain the statistical method, and the new SBP method is applied to the Y-12 group. The true positive rate and specificity of the new method were estimated to be 86% and 97%, respectively. An electronic notebook that is accessible via the Internet was used in

  12. Some features of beryllium corrosion behavior in Be-liquid Li-V-4Ti-4Cr alloy system

    International Nuclear Information System (INIS)

    Recent experimental results on beryllium corrosion behavior in a V-4Ti-4Cr alloy, liquid lithium static system during testing for 200-500 h at temperatures from 600 to 800 deg. C are presented. The influence of test conditions (temperature, duration and lithium purity) and beryllium characteristics (microstructure, grain size and chemical composition) on weight loss of beryllium and penetration of lithium into beryllium are discussed. Results of compressive tests for beryllium specimens before and after corrosion testing are also introduced

  13. Hanford Site Beryllium Program: Past, Present, and Future - 12428

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) has a long history of beryllium use because of the element's broad application to many nuclear operations and processes. At the Hanford Site beryllium alloy was used to fabricate parts for reactors, including fuel rods for the N-Reactor during plutonium production. Because of continued confirmed cases of chronic beryllium disease (CBD), and data suggesting CBD occurs at exposures to low-level concentrations, the DOE decided to issue a rule to further protect federal and contractor workers from hazards associated with exposure to beryllium. When the beryllium rule was issued in 1999, each of the Hanford Site contractors developed a Chronic Beryllium Disease Prevention Program (CBDPP) and initial site wide beryllium inventories. A new site-wide CBDPP, applicable to all Hanford contractors, was issued in May, 2009. In the spring of 2010 the DOE Headquarters Office of Health, Safety, and Security (HSS) conducted an independent inspection to evaluate the status of implementation of the Hanford Site Chronic Beryllium Disease Prevention Program (CBDPP). The report identified four Findings and 12 cross-cutting Opportunities for Improvement (OFIs). A corrective action plan (CAP) was developed to address the Findings and crosscutting OFIs. The DOE directed affected site contractors to identify dedicated resources to participate in development of the CAP, along with involving stakeholders. The CAP included general and contractor-specific recommendations. Following initiation of actions to implement the approved CAP, it became apparent that additional definition of product deliverables was necessary to assure that expectations were adequately addressed and CAP actions could be closed. Consequently, a supplement to the original CAP was prepared and transmitted to DOE-HQ for approval. Development of the supplemental CAP was an eight month effort. From the onset a core group of CAP development members were identified to develop a mechanism for

  14. Contribution to the study of 8Be energy levels obtained during the reaction 6Li(d,α)α

    International Nuclear Information System (INIS)

    The reaction 6Li(d,α) is interpreted using the theory of Humblet and Rosenfeld. This theory is briefly reviewed and compared with that of Wigner. The intervention of the 4+ level, indicated in the study of the reaction 7Li(p,α), is suggested. A good fit to the experimental data is obtained assuming the level scheme (0+ 22.64 MeV), (4+ 22.82 MeV), (2+ 24.97 MeV). However the scheme proposed by Mani (22.5 MeV 2+; 24.0 MeV 0+; 25.2 MeV 2+) on the basis of the Wigner theory, cannot be rejected. (author)

  15. Reaction center for C3H8-SCR of NOx under water vapor presence in Co-BEA* zeolites

    Czech Academy of Sciences Publication Activity Database

    Dědeček, Jiří; Jirglová, Hana; Sobalík, Zdeněk; Sklenák, Štěpán; Sazama, Petr; Kreibich, Viktor

    Hiroshima: Hiroshima University, 2012. s. 1-2. [International Symposium on Zeolites and MicroPorous Crystals. 28.07.2012-01.08.2012, Hiroshima] R&D Projects: GA AV ČR IAA400400904; GA AV ČR IAA400400812; GA ČR GAP106/11/0624 Institutional support: RVO:61388955 Keywords : zeolites * reaction center Subject RIV: CF - Physical ; Theoretical Chemistry

  16. Directed evolution of a (βα)8-barrel enzyme to catalyze related reactions in two different metabolic pathways

    OpenAIRE

    Jürgens, Catharina; Strom, Alexander; Wegener, Dennis; Hettwer, Stefan; Wilmanns, Matthias; Sterner, Reinhard

    2000-01-01

    Enzymes participating in different metabolic pathways often have similar catalytic mechanisms and structures, suggesting their evolution from a common ancestral precursor enzyme. We sought to create a precursor-like enzyme for N′-[(5′-phosphoribosyl)formimino]-5-aminoimidazole-4-carboxamide ribonucleotide (ProFAR) isomerase (HisA; EC 5.3.1.16) and phosphoribosylanthranilate (PRA) isomerase (TrpF; EC 5.3.1.24), which catalyze similar reactions in the biosynthesis of the amino acids histidine a...

  17. Excitation functions of some neutron threshold reactions on 89Y in the energy range of 7.8 to 14.7 MeV

    International Nuclear Information System (INIS)

    Excitation functions were measured for 89Y(n,2n)88Y, 89Y(n,p)89Sr and 89Y(n,α)86Rb reactions from their respective thresholds up to 14.7 MeV using the activation technique. Quasi-monoenergetic neutrons in the energy range of 7.8 to 13.3 MeV were produced via the 2H(d,n)3He reaction on a D2 gas target at the Juelich compact cyclotron (CV 28), and monoenergetic neutrons in the range of 13.8 to 14.7 MeV using the D-T neutron generator at Debrecen. For characterization of 88Y and 86Rb, high-resolution γ-ray spectrometry was applied. The latter product was also separated radiochemically and characterized by low-level β- counting; the results obtained using the two counting methods were generally in good agreement. The product 89Sr is a pure β- emitter: its activity was exclusively assayed via radiochemical separation and β- counting. Our results agree with the literature values on the (n,2n) reaction and provide the first consistent set of data on the (n,p) and (n,α) reactions near their thresholds. Statistical model calculations incorporating precompound effects were performed on the three excitation functions under consideration. The experimental and theoretical results were found to be in good agreement. Some systematic trends in the excitation functions in this mass region are discussed. (orig.)

  18. Elucidation of the mechanism of reaction between S2O8(2-), Selenite and Mn2+ in aqueous solution and limestone-gypsum FGD liquor.

    Science.gov (United States)

    Akiho, Hiroyuki; Ito, Shigeo; Matsuda, Hiromitsu; Yoshioka, Toshiaki

    2013-10-01

    The mechanism of reaction between peroxodisulfate ion (S2O8(2-)), selenite (Se(IV)O3(2-)) and Mn(2+) as an inhibitor of selenite oxidation was studied using aqueous solutions composed of commercial reagents, as well as limestone-gypsum flue gas desulfurization (FGD) liquors sampled from coal fired power plants. The oxidation of selenite to selenate (Se(VI)O4(2-)) is promoted by the sulfate ion radical (SO4(-)) which results from decomposition of S2O8(2-). In the presence of Mn(2+), selenite oxidation was prevented due to the difference in rates of reaction with SO4(-). The ratio of the oxidation rate constants of selenite and Mn(2+) with SO4(-) was determined over a temperature range of 40-60 °C, and was found to be little influenced by the various coexisting components in FGD liquors. PMID:24015970

  19. Virtual Instrument for Determining Rate Constant of Second-Order Reaction by pX Based on LabVIEW 8.0

    OpenAIRE

    Hu Meng; Jiang-Yuan Li; Yong-Huai Tang

    2009-01-01

    The virtual instrument system based on LabVIEW 8.0 for ion analyzer which can measure and analyze ion concentrations in solution is developed and comprises homemade conditioning circuit, data acquiring board, and computer. It can calibrate slope, temperature, and positioning automatically. When applied to determine the reaction rate constant by pX, it achieved live acquiring, real-time displaying, automatical processing of testing data, generating the report of results; and other functions. T...

  20. Microstructures and Mechanical Properties of TiCp/Al-4.5Cu-0.8Mg Composites by Direct Reaction Synthesis

    Institute of Scientific and Technical Information of China (English)

    Mingzhen MA; Dayong CAI; Tianhua WEI

    2003-01-01

    Direct reaction synthesis (DRS), based on the principle of self-propagating high-temperature synthesis (SHS), is anew method for preparing particulate metal matrix composites. TiCP/Al-4.5Cu-0.8Mg composites were fabricatedby DRS. Particulate composites were fabricated with Ti carbide (TiC) particles, generally less than 1.0 μm. Thereacted, thermal extruded samples exhibit a homogeneous distribution of fine TiC particles in Al-4.5Cu-0.8Mg matrix.Mechanical property evaluation of the composites has revealed a very high tensile strength relative to the matrixalloy. Fractographic analysis indicates ductile failure.

  1. Branching ratio of 8Be* high excited states in the 10B(dα)2α and 10B(dα)p7Li reaction

    International Nuclear Information System (INIS)

    Three-particle channels of 10B(dα)2α and 10B(dα)p7Li reactions with the excitation of short-living 19.86, 4+ and 20.1 MeV, 2+ state of 8Be* nucleus are investigated under 13.6 MeV incident deuteron energy in kinematically complete experiment. Angular correlation functions for these states and branching ratio by α-particle and proton channels are obtained. Spatial anisotropy of 8Be* nucleus parameter change as of two-cluster non-isolated subsystem is revealed

  2. Synthesis of Be–Ti–V ternary beryllium intermetallic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae-Hwan, E-mail: kim.jaehwan@jaea.go.jp; Nakamichi, Masaru

    2015-08-15

    Highlights: • Preliminary synthesis of ternary Be–Ti–V beryllides was investigated. • An area fraction of Be phase increased with increase of V amount in the beryllide because of increasing melting temperature. • The increase of Be phase fraction resulted in increase of weight gain as well as H{sub 2} generation. • The beryllides with lower V contents indicated to better phase stability at high temperature. - Abstract: Beryllium intermetallic compounds (beryllides) such as Be{sub 12}Ti and Be{sub 12}V are the most promising advanced neutron multipliers in demonstration power reactors. Advanced neutron multipliers are being developed by Japan and the EU as part of their Broader Approach activities. It has been previously shown, however, that beryllides are too brittle to fabricate into pebble- or rod-like shapes using conventional methods such as arc melting and hot isostatic pressing. To overcome this issue, we developed a new combined plasma sintering and rotating electrode method for the fabrication of beryllide rods and pebbles. Previously, we prepared a beryllide pebble with a Be–7.7 at.% Ti composition as the stoichiometric value of the Be{sub 12}Ti phase; however, Be{sub 17}Ti{sub 2} and Be phases were present along with the Be{sub 12}Ti phase that formed as the result of a peritectic reaction due to re-melting during granulation using the rotating electrode method. This Be phase was found to be highly reactive with oxygen and water vapor. Accordingly, to investigate the Be phase reduction and applicability for fabrication of electrodes prior to granulation using the rotating electrode method, Be–Ti–V ternary beryllides were synthesized using the plasma sintering method. Surface observation results indicated that increasing plasma sintering time and V addition led to an increase in the intermetallic compound phases compared with plasma-sintered beryllide with a Be–7.7 at.% Ti composition. Additionally, evaluation of the reactivity of

  3. Hyperon and negative particle production at central rapidity in proton-Beryllium interactions at 158 GeV/c

    International Nuclear Information System (INIS)

    A study of the strangeness enhancement in Lead-Lead collisions with respect to proton-induced reactions is being carried out at the CERN SPS by the WA97 experiment: up to now, data from proton-Lead collisions have been used as a reference sample. In this paper we report on a study of particle production in proton-Beryllium collisions. These collisions are expected to constitute a better reference sample than p-Pb, because of the lighter target. The analysis of hyperon and negative particle production is presented and the results are compared with those previously obtained from Pb-Pb and p-Pb collisions

  4. Hyperon and negative particle production at central rapidity in proton-beryllium interactions at 158 GeV/c

    CERN Document Server

    Antinori, Federico; Beusch, Werner; Bloodworth, Ian J; Caliandro, R; Carrer, N; Di Bari, D; Di Liberto, S; Elia, D; Evans, D; Fanebust, K; Fini, R A; Ftácnik, J; Ghidini, B; Grella, G; Helstrup, H; Holme, A K; Huss, D; Jacholkowski, A; Jones, G T; Kinson, J B; Knudson, K P; Králik, I; Lenti, V; Lietava, R; Loconsole, R A; Løvhøiden, G; Manzari, V; Mazzoni, M A; Meddi, F; Michalon, A; Michalon-Mentzer, M E; Morando, M; Norman, P I; Pastircák, B; Quercigh, Emanuele; Romano, G; Safarík, K; Sándor, L; Segato, G F; Staroba, P; Thompson, M; Thorsteinsen, T F; Torrieri, G D; Tveter, T S; Urbán, J; Villalobos Baillie, O; Virgili, T; Votruba, M F; Závada, P

    1999-01-01

    A study of the strangeness enhancement in lead-lead collisions with respect to proton-induced reactions is being carried out at the CERN SPS by the WA97 experiment: up to now, data from proton-lead collisions have been used as a reference sample. In this paper we report on a study of particle production in proton-beryllium collisions. These collisions are expected to constitute a better reference sample than p-Pb, because of the lighter target. The analysis of hyperon and negative particle production is presented and the results are compared with those previously obtained from Pb-Pb and p-Pb collisions. (6 refs).

  5. TEM study of beryllium pebbles after neutron irradiation up to 3000 appm helium production

    Energy Technology Data Exchange (ETDEWEB)

    Klimenkov, M., E-mail: michael.klimenkov@kit.edu [Institute for Applied Materials – Applied Materials Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Chakin, V.; Moeslang, A. [Institute for Applied Materials – Applied Materials Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Rolli, R. [Institute for Applied Materials – Materials and Biomechanics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2013-11-15

    Beryllium is planned to be used as a neutron multiplier in the Helium Cooled Pebble Bed (HCPB) European concept of a breeding blanket of DEMO. In order to evaluate the irradiation performance, individual pebbles and constrained pebble beds were neutron irradiated at temperatures typical for fusion blanket. Beryllium pebbles with a diameter of 1 mm produced by the Rotating Electrode Method were subjected to a TEM study after irradiation at the HFR, Petten, at temperatures of 686, 753, 861, and 968 K. The helium production in the pebbles was calculated in the range from 2090 to 3090 appm. Gas bubbles as disks of hexagonal shape were observed for all four irradiation temperatures. The disks were oriented in the (0 0 0 1) basal plane with a height directed along the [0 0 0 1] “c” axis. The average diameters of the bubbles increase from 7.5 to 80 nm with increasing irradiation temperature, the bulk densities accordingly decrease from 4.4 × 10{sup 22} to 3.8 × 10{sup 20} m{sup −3}. With increasing irradiation temperature, the swelling of the pebbles increases from 0.6% at 686 K up to 6.5% at 968 K.

  6. Interaction of implanted deuterium and helium with beryllium: radiation enhanced oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Langley, R.A.

    1979-01-01

    The interaction of implanted deuterium and helium with beryllium is of significant interest in the application of first wall coatings and other components of fusion reactors. Electropolished polycrystalline beryllium was first implanted with an Xe backscatter marker at 1.98 MeV followed by either implantation with 5 keV diatomic deuterium or helium. A 2.0 MeV He beam was used to analyze for impurity buildup; namely oxygen. The oxide layer thickness was found to increase linearly with increasing implant fluence. A 2.5 MeV H/sup +/ beam was used to depth profile the D and He by ion backscattering. In addition the retention of the implant was measured as a function of the implant fluence. The mean depth of the implant was found to agree with theoretical range calculations. Scanning electron microscopy was used to observe blister formation. No blisters were observed for implanted D but for implanted He blisters occurred at approx. 1.75 x 10/sup 17/ He cm/sup -2/. The blister diameter increased with increasing implant fluence from about 0.8 ..mu..m at 10/sup 18/ He cm/sup -2/ to 5.5 ..mu..m at 3 x 10/sup 18/ He cm/sup -2/.

  7. Graphite furnace atomic absorption spectrometry as a routine method for the quantification of beryllium in blood and serum

    Directory of Open Access Journals (Sweden)

    Brousseau Pauline

    2008-07-01

    Full Text Available Abstract Background A routine method for the quantification of beryllium in biological fluids is essential for the development of a chelation therapy for Chronic Beryllium Disease (CBD. We describe a procedure for the direct determination of beryllium in undigested micro quantities of human blood and serum using graphite furnace atomic absorption spectrometry. Blood and serum samples are prepared respectively by a simple 8-fold and 5-fold dilution with a Nash Reagent. Three experimental setups are compared: using no modifier, using magnesium nitrate and using palladium/citric acid as chemical modifiers. Results In serum, both modifiers did not improve the method sensitivity, the optimal pyrolysis and atomization temperatures are 1000°C and 2900°C, respectively. In blood, 6 μg of magnesium nitrate was found to improve the method sensitivity. The optimal pyrolysis and atomization temperatures were 800°C and 2800°C respectively. Conclusion In serum, the method detection limit was 2 ng l-1, the characteristic mass was 0.22 (± 0.07 pg and the accuracy ranged from 95 to 100%. In blood, the detection limit was 7 ng l-1, the characteristic mass was 0.20 (± 0.02 pg and the accuracy ranged from 99 to 101%.

  8. Fallout beryllium-7 as a soil and sediment tracer in river basins: current status and needs

    Science.gov (United States)

    Taylor, Alex; Blake, Will H.; Smith, Hugh G.; Mabit, Lionel; Keith-Roach, Miranda J.

    2013-04-01

    Beryllium-7 is a cosmogenic radionuclide formed in the upper atmosphere by cosmic ray spallation of nitrogen and oxygen. Its constant natural production and fallout via precipitation coupled with its ability to bind to soil particles have underpinned its application as a sediment tracer. The short half-life of beryllium-7 (53.3 days) lends itself to tracing sediment dynamics over short time periods, thus, enabling assessment of the effect of land use change upon soil redistribution. Although beryllium-7 has been widely applied as a tracer to date, there remain crucial gaps in understanding relating to the assumptions for its use. To further support the application of beryllium-7 as a tracer across a range of environments requires consideration of both the current strengths and shortcomings of the technique to direct research needs. Here we review research surrounding the assumptions underpinning beryllium-7 use as a tracer and identify key knowledge gaps relating to i) the effects of rain shadowing and vegetation interception upon beryllium-7 fallout uniformity at the hillslope-scale; ii) the effect of preferential flow pathways upon beryllium-7 depth distribution in soil and overland flow upon beryllium-7 inventory uniformity and iii) the potential for beryllium-7 desorption in saline and reducing environments. To provide continued support for the use of beryllium-7 as a hillslope and catchment-scale tracer, there is an urgent need to undertake further research to quantify the effect of these factors upon tracer estimates.

  9. Three-coordinate beryllium β-diketiminates: synthesis and reduction chemistry.

    Science.gov (United States)

    Arrowsmith, Merle; Hill, Michael S; Kociok-Köhn, Gabriele; MacDougall, Dugald J; Mahon, Mary F; Mallov, Ian

    2012-12-17

    A series of mononuclear, heteroleptic beryllium complexes supported by the monoanionic β-diketiminate ligand [HC{CMeNDipp}(2)](-) (L; Dipp = 2,6-diisopropylphenyl) have been synthesized. Halide complexes of the form [LBeX] (X = Cl, I) and a bis(trimethylsilyl)amide complex were produced via salt metathesis routes. Alkylberyllium β-diketiminate complexes of the form [LBeR] (R = Me, (n)Bu) were obtained by salt metathesis from the chloride precursor [LBeCl]. Controlled hydrolysis of [LBeMe] afforded an air-stable, monomeric β-diketiminatoberyllium hydroxide complex. [LBeMe] also underwent facile protonolysis with alcohols to form the corresponding β-diketiminatoberyllium alkoxides [LBeOR] (R = Me, (t)Bu, Ph). High temperatures and prolonged reaction times were required for protonolysis of [LBeMe] with primary amines to yield the β-diketiminatoberyllium amide complexes [LBeNHR] (R = (n)Bu, CH(2)Ph, Ph). No reactions were observed between [LBeMe] and silanes, terminal acetylenes, or secondary amines. All compounds were characterized by (1)H, (13)C, and (9)Be NMR spectroscopy and, in most cases, by X-ray crystallography. Reduction of the beryllium chloride complex with potassium metal resulted in apparent hydrogen-atom transfer between two β-diketiminate backbones, yielding two dimeric, potassium chloride bridged diamidoberyllium species. X-ray analysis of a cocrystallized mixture of the 18-crown-6 adducts of these species allowed unambiguous identification of the two reduced diketiminate ligands, one of which had been deprotonated at a backbone methyl substituent and the other reduced by hydride addition to the β-imine position. It is proposed that this process occurs by the formation of an unobserved radical anion species and intermolecular hydrogen-atom transfer by a radical-based hydrogen abstraction mechanism. PMID:23215345

  10. Search for the existence of the tetra-neutron through the He{sup 8}(d,Li{sup 6})4n nuclear reaction; Recherche de l'existence eventuelle du tetraneutron via la reaction de transfert {sup 8}He(d, {sup 6}Li)4n

    Energy Technology Data Exchange (ETDEWEB)

    Rich, E

    2005-10-15

    The He{sup 8}(d,Li{sup 6})4n reaction is studied through reverse kinematics: a radioactive beam of He{sup 8} nuclei impinges on a CD{sub 2} target. The measurement of the energy spectrum and emission angle distribution of Li{sup 6} has allowed us to determine by applying kinematics laws the excitation energy spectrum of the 4 neutrons system released in the reaction. The first chapter recalls the main features of the nucleon-nucleon interaction and reviews recent experiments on multi-neutrons. The second chapter presents the experimental setting from the production of the He{sup 8} beam at GANIL to the detection system of the reaction products via the data acquisition system. The method of the missing mass gives the mass of the 4 neutron system. The third and fourth chapters deal with the calibration of the detection system, the missing mass method is applied to the following reactions: C{sup 12}(d,Li{sup 6})Be{sup 8}, C{sup 12}(d,t)C{sup 11} and C{sup 12}(d,He{sup 3})B{sup 11}. The last chapter presents the experimental results. The analysis of the excitation energy spectrum of the 4 neutron systems shows no evidence for the existence of a bound state. We get a maximal limit of 60 {mu}b for the production cross section of a bound state. Complementary results concerning the excitation energy spectra of the di-neutron and tri-neutron released in the reactions: He{sup 8}(d,Li{sup 8})2n and He{sup 8}(d,Li{sup 7})3n are also presented. (A.C.)

  11. An overview on incomplete fusion reaction dynamics at energy range ∼ 3-8 MeV/A

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Rahbar, E-mail: rahbarali1@rediffmail.com [Department of Physics, G. F. (P. G.) College, Shahjahanpur-242001 (India); Singh, D. [Centre for Applied Physics, Central University of Jharkhand, Ranchi-825202 (India); Ansari, M. Afzal [Department of Physics, Aligarh Muslim University, Aligarh-202002 (India); Kumar, Rakesh; Muralithar, S.; Golda, K. S.; Singh, R. P.; Bhowmik, R. K. [Inter University Accelerator Centre, New Delhi-110067 (India); Rashid, M. H.; Guin, R.; Das, S. K. [Variable Energy Cyclotron Centre, Kolkata-700064 (India)

    2014-08-14

    The information of ICF reaction has been obtained from the measurement of excitation function (EF) of ERs populated in the interaction of {sup 20}Ne and {sup 16}O on {sup 55}Mn, {sup 159}Tb and {sup 156}Gd targets. Sizable enhancement in the measured cross-sections has been observed in α-emitting channels over theoretical predictions, which has been attributed to ICF of the projectile. In order to confirm the findings of the measurements and analysis of EFs, the forward recoil range distributions of ERs populated in {sup 20}Ne+{sup 159}Tb (E ∼165MeV) and {sup 16}O+{sup 156}Gd (E ∼ 72, 82 and 93MeV) systems, have been measured. It has been observed that peaks appearing at different cumulative thicknesses in the stopping medium are related with different degree of linear momentum transfer from projectile to target nucleus by adopting the break-up fusion model consideration. In order to deduce the angular momentum involved in various CF and / or ICF reaction products, spin distribution and side-feeding intensity profiles of radio-nuclides populated via CF and ICF channels in {sup 16}O+{sup 160}Gd system at energy, E ∼ 5.6 MeV/A, have been studied. Spin distribution of ICF products are found to be distinctly different than that observed from CF products.

  12. Co-BEA* zeolites with a reaction center for C3H8-SCR of NOx under water vapor presence

    Czech Academy of Sciences Publication Activity Database

    Jirglová, Hana; Dědeček, Jiří; Sobalík, Zdeněk; Sklenák, Štěpán; Sazama, Petr; Kreibich, Viktor

    VIenna: Institute of Materials Chemistry, TU Vienna, 2012. s. 127-128. ISBN 978-3-900554-71-2. [Pannonian Symposium on Catalysis /11./. 03.09.2012-07.09.2012, Obergurgl] Keywords : C3H8- SCR * zeolites Subject RIV: CF - Physical ; Theoretical Chemistry

  13. Measurement of the efficient cross section of the reaction 7Be(p, γ)8B at low energies and implications in the problem of solar neutrinos

    International Nuclear Information System (INIS)

    The 8B produced inside the sun through the reaction 7Be(p,γ)8B is the main, and even unique, source of high energy neutrinos detected in most solar neutrino detection experiments, except with Gallex and Sage. These experiments have all measured a neutrinos flux lower than the one predicted by solar models. Several explanations have been proposed to explain this deficit, but all require a precise knowledge of the efficient cross-section of the reaction 7Be(p,γ)8B, because the neutrinos flux of 8B is directly proportional to this reaction. The direct measurement of this cross section for the solar energy is impossible because of its low value (about 1 femto-barn). In order to get round this problem, the cross sections are measured at higher energy and extrapolated to the solar energy using a theoretical energy dependence. The 6 previous experimental determinations of the efficient cross section were shared in two distinct groups with differences of about 30% which leads to an uncertainty of the same order on the high energy neutrinos flux. The re-measurement of the cross section of this reaction with a better precision is thus of prime importance. A direct measurement of the cross section in the energy range comprised between 0.35 and 1.4 MeV (cm) has been performed first. These experiments have permitted the precise measurement of each parameter involved in the determination of the cross section. Then, measurements of the cross section have been carried out with the PAPAP accelerator at 185.8, 134.7 and 111.7 keV, the lowest mass center energy never reached before. The results are in excellent agreement with those obtained at higher energies. The value obtained by extrapolation of these data for the astrophysical factor S17(0) is 19.21.3 EV-B, which leads to a significant reduction of the uncertainty on the high energy neutrinos flux of 8B. (J.S.)

  14. High sensitivity boron quantification in bulk silicon using the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be nuclear reaction

    Energy Technology Data Exchange (ETDEWEB)

    Moro, Marcos V.; Silva, Tiago F. da; Added, Nemitala; Rizutto, Marcia A.; Tabacniks, Manfredo H. [Instituto de Fisica da Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil); Neira, John B.; Neto, Joao B. F. [Institute of Research Tecnology, Cidade Universitaria, SP, 05508-091 (Brazil)

    2013-05-06

    There is a great need to quantify sub-ppm levels of boron in bulk silicon. There are several methods to analyze B in Si: Nuclear Reaction Analysis using the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be reaction exhibits a quantification limit of some hundreds ppm of B in Si. Heavy Ion Elastic Recoil Detection Analysis offers a detection limit of 5 to 10 at. ppm. Secondary Ion Mass Spectrometry is the method of choice of the semiconductor industry for the analysis of B in Si. This work verifies the use of NRA to quantify B in Si, and the corresponding detection limits. Proton beam with 1.6 up to 2.6 MeV was used to obtain the cross-section of the {sup 11}B(p,{alpha}{sub 0}){sup 8}Be nuclear reaction at 170 Degree-Sign scattering angle. The results show good agreementwith literature indicating that the quantification of boron in silicon can be achieved at 100 ppm level (high sensitivity) at LAMFI-IFUSP with about 16% uncertainty. Increasing the detection solid angle and the collected beam charge, can reduce the detection limit to less than 100 ppm meeting present technological needs.

  15. Measurements of the Total Reaction Cross Sections for 6,8He and 8,9Li Nuclei with Energies of (25-45)A Mev on natAl, natTa and natPb

    Science.gov (United States)

    Erdemchimeg, B.; Artukh, A. G.; Klygin, S. A.; Kononenko, G. A.; Kyslukha, D. A.; Sereda, Yu. M.; Vorontzov, A. N.; Lukyanov, S. M.; Penionzhkevich, Yu. E.; Davaa, S.; Khuukhenkhuu, G.; Borcea, C.; Rotaru, F.; Stanoiu, M.; Martina, L.; Saillant, F.; Raine, B.

    2015-06-01

    The total nuclear reaction cross sections (σR) measurements have long been of interest since they tell us about the radii and transparency of these nuclei and give clues to understanding of their structure. For studies of unstable nuclei, in particular the physical properties of halo nuclei and the neutron skin thickness, it is valuable to know not only the root-mean-square radii (rms) but it is important to know the details of nucleusnucleus potentials. Our goal was to study total reaction cross sections (σR) by a direct measurement technique (the so-called beam attenuation or transmission method) which allows to extract model independent information. The interaction radii for 6He, 8,9Li were extracted, which are in agreement with the previous measurement at the similar energies (about a few tens of AMeV) Our results show a tendency of increasing radii as function of mass of the secondary targets.

  16. JET-ISX-B beryllium limiter experiment safety analysis report and operational safety requirements

    International Nuclear Information System (INIS)

    An experiment to evaluate the suitability of beryllium as a limiter material has been completed on the ISX-B tokamak. The experiment consisted of two phases: (1) the initial operation and characterization in the ISX experiment, and a period of continued operation to the specified surface fluence (1022 atoms/cm2) of hydrogen ions; and (2) the disassembly, decontamination, or disposal of the ISX facility. During these two phases of the project, the possibility existed for beryllium and/or beryllium oxide powder to be produced inside the vacuum vessel. Beryllium dust is a highly toxic material, and extensive precautions are required to prevent the release of the beryllium into the experimental work area and to prevent the contamination of personnel working on the device. Details of the health hazards associated with beryllium and the appropriate precautions are presented. Also described in appendixes to this report are the various operational safety requirements for the project

  17. Beryllium coating produced by evaporation-condensation method and some their properties

    Energy Technology Data Exchange (ETDEWEB)

    Pepekin, G.I.; Anisimov, A.B.; Chernikov, A.S.; Mozherinn, S.I.; Pirogov, A.A. [SRI SIA Lutch., Podolsk (Russian Federation)

    1998-01-01

    The method of vacuum evaporation-condensation for deposition of beryllium coatings on metal substrates, considered in the paper, side by side with a plasma-spray method is attractive fon ITER application. In particular this technique may be useful for repair the surface of eroded tiles which is operated in a strong magnetic field. The possibility of deposition of beryllium coatings with the rate of layer growth 0.1-0.2 mm/h is shown. The compatibility of beryllium coating with copper or stainless steel substrate is provided due to intermediate barrier. The results of examination of microstructure, microhardness, porosity, thermal and physical properties and stability under thermal cycling of beryllium materials are presented. The value of thermal expansion coefficient and thermal conductivity of condensed beryllium are approximately the same as for industrial grade material produced by powder mettalurgy technique. However, the condensed beryllium has higher purity (up to 99.9-99.99 % wt.). (author)

  18. 5. IEA International workshop on beryllium technology for fusion. Book of abstracts

    International Nuclear Information System (INIS)

    The collection includes the abstracts of reports presented to the 5-th IEA international workshop on beryllium technology for fusion. The themes of reports are as follows: status of beryllium technology for fusion in Russia; manufacturing and testing of Be armoured first wall mock-up for ITER; development of the process of diffusion welding of metals stainless steel-copper-beryllium into a single composite; some features of beryllium-laser beam interaction; the effect of irradiation dose on tritium and helium release from neutron irradiated beryllium; thermal properties of neutron irradiated Be12Ti. The results of investigating the mechanical properties variation and swelling of beryllium under high temperature neutron irradiation are presented

  19. Quantum-chemical approach to cohesive properties of metallic beryllium

    International Nuclear Information System (INIS)

    Calculations based upon the incremental approach, i.e. an expansion of the correlation energy in terms of one-body, two-body, and higher-order contributions from localized orbital groups, have been performed for metallic beryllium. We apply an embedding scheme which has been successfully applied recently to ground-state properties of magnesium and group 12 elements. This scheme forces localization in metallic-like model systems and allows for a gradual delocalization within the incremental approach. Quantum-chemical methods of the coupled-cluster and multi-reference configuration interaction type are used for evaluating individual increments. Results are given for the cohesive energy and lattice constants of beryllium, and it is shown that further development of the approach is needed for this difficult case

  20. Effects of beryllium-compounds on the hen. 2. Comm

    International Nuclear Information System (INIS)

    After oral application of 7Be2+ this cation is relative slowly absorbed from the intestine. The highest proportion of 7Be appeared in the feces. The absorbed 7Be has been found in the feathers, the bones and in the muscles as well as in the mucosa of the stomach and the intestine. Relative low is the accumulation in the liver and the kidneys as well as in the brain and the spinal cord. After i.v. application a high proportion of 7Be has been observed in the eggs. The rest of the applied radio-beryllium has been accumulated 7Be in the metabolically active tissues is removed very slowly. In contrast to this observation radio-beryllium disappeared relatively rapidly from the blood. (orig.)

  1. A charge-density study of crystalline beryllium

    International Nuclear Information System (INIS)

    The X-ray structure factors for crystalline beryllium measured by Brown [Phil. Mag. (1972), 26, 1377] have been analyzed with multipole deformation functions for charge-density information. Single exponential radial functions were used for the valence charge density. A valence monopole plus the three harmonics, P35(cos theta) sin 3phi, P6(cos theta) and P37(cos theta) sin 3phi, provide a least-squares fit to the data with Rsub(w)=0.0081. The superposition of these density functions describes a bonding charge density between Be atoms along the c axis through the tetrahedral vacancy. The results reported here are in qualitative agreement with a recent pseudo-potential calculation of metallic beryllium. The final residuals in the analysis are largest at high sin theta/lambda values. This suggests that core charge deformation is present and/or anharmonic motion of the nuclei is appreciable. (Auth.)

  2. Fabrication methods for beryllium spacecraft components (Series 2)

    International Nuclear Information System (INIS)

    The aims of this paper are to conserve and yet promote the use of one of the most versatile metal elements available to the practising engineer. The scope of the work described involves the selection of candidate components suitable for manufacture in beryllium. Evaluation by mathematical modelling using finite element techniques is used as an aid in determining the principal load paths in a structural component. Cost effective techniques which are objectively analysed suggest that the conservation of raw beryllia can best be achieved using recently developed plasma spray methods. The British Aircraft Corporation have been investigating methods of plasma spraying beryllium with A.W.R.E. and current developments are giving clear indications that for certain future space applications plasma spray is the technique which most nearly meets the conservation objective. (author)

  3. Fabrication of beryllium spheres and its validation tests

    International Nuclear Information System (INIS)

    A sphere-pack blanket concept using small size spheres of beryllium is one of the promising design concept of the ITER blanket, because the sphere-pack can accommodate the size deformation due to neutron irradiation damage, helium swelling and cyclic temperature changes. Preliminary R and D for an industrial fabrication technology of beryllium spheres (1.0 ± 0.3 mm in diameter) has been started as part of feasibility study of Japanese blanket concept of layered sphere-pack configuration. The following tests were performed in the several demo-fabrications; feasibility of size distribution control, material characterization such as macroscopic and microscopic structure analysis, impurity analysis, and attainable packing density, mechanical integrity under various thermal cycling conditions. (author)

  4. Enhancement of delayed hypersensitivity inflammatory reactions in guinea pig skin by 12(R)-hydroxy-5,8,14-eicosatrienoic acid.

    Science.gov (United States)

    Conners, M S; Schwartzman, M L; Quan, X; Heilman, E; Chauhan, K; Falck, J R; Godfrey, H P

    1995-01-01

    Delayed-type hypersensitivity (DTH) reactions are initiated by sensitized T cells. Their progression is dependent upon the local release of various autacoids, including cytokines and eicosanoids, by T cells, infiltrating inflammatory cells, and resident tissue cells. 12(R)-hydroxy-5,8,14-eicosatrienoic acid [12(R)-HETrE], an eicosanoid produced by skin and cornea, possesses potent proinflammatory properties at picomolar concentrations including vasodilation, increase in membrane permeability, neutrophil chemotaxis, and angiogenesis. Because DTH reactions are associated with many of these same phenomena, we examined the effect of 12(R)-HETrE and related 12-hydroxyeicosanoids on the expression of DTH to purified protein derivative of tuberculin in sensitized guinea pigs. In the absence of purified protein derivative of tuberculin, none of the eicosanoids evoked erythema or edema after intradermal injection at doses up to 100 pmol. When injected together with purified protein derivative of tuberculin, 12(R)-hydroxy-5,8,10,14-eicosatetraenoic acid [12(R)-HETE], but not its enantiomer 12(S)-HETE, significantly inhibited macroscopic expression of delayed reactivity (erythema) only at the highest dose tested, 10 pmol. In contrast, 12(R)-HETrE significantly enhanced expression of DTH at doses between 1 fmol and 1 pmol (50% and 30% increases above control, respectively). Its stereoisomer, 12(S)-HETrE, did not enhance DTH at any tested dose, but was able to block the activity of 12(R)-HETrE when injected simultaneously. Enhancement or inhibition of visible skin responses was not associated with qualitative or quantitative changes in cellular infiltrates at the reaction site. 12(R)-HETrE had no effect on the nonimmunologic inflammatory skin reaction induced by phorbol myristate acetate, suggesting selectivity toward DTH. We conclude that 12(R)-HETrE enhances DTH via a yet to be determined mechanism and that its stereoisomer, 12(S)-HETrE, may be a useful antagonist for

  5. Low-energy electronic stopping for boron in beryllium

    International Nuclear Information System (INIS)

    The range distribution for 50-keV boron bombarding beryllium was measured by an energetic ion-beam backscattering technique using helium ions. This distribution was compared with the range calculated with computer code EDEP1, with the result k 0.101 ± 0.013 for the electronic-stopping k-value. This value is compared with the results of recent interpolations from measurements of other elements. (author)

  6. Thermal fatigue behavior of US and Russian grades of beryllium

    International Nuclear Information System (INIS)

    A novel technique has been used to test the relative low cycle thermal fatigue resistance of different grades of US and Russian beryllium which is proposed as plasma facing armor for fusion reactor first wall, limiter, and divertor components. The 30 KW electron beam test system at Sandia National Laboratories was used to sweep the beam spot along one direction at 1 Hz. This produces a localized temperature ''spike'' of 750 degrees C for each pass of the beam. Large thermal stress in excess of the yield strength are generated due to very high spot heat flux, 250 MW/m2. Cyclic plastic strains on the order of 0.6% produced visible cracking on the heated surface in less than 3000 cycles. An in-vacuo fiber optic borescope was used to visually inspect the beryllium surfaces for crack initiation. Grades of US beryllium tested included: S-65C, S-65H, S-200F, S-300F-H, Sr-200, I-400, extruded high purity. HIP'd sperical powder, porous beryllium (94% and 98% dense), Be/30% BeO, Be/60% BeO, and TiBe12. Russian grades included: TGP-56, TShGT, DShG-200, and TShG-56. Both the number of cycles to crack initiation, and the depth of crack propagation, were measured. The most fatigue resistant grades were S-65C, DShG-200, TShGT, and TShG-56. Rolled sheet Be(SR-200) showed excellent crack propagation resistance in the plane of rolling, despite early formation of delamination cracks. Only one sample showed no evidence of surface melting, Extruded (T). Metallographic and chemical analyses are provided. Good agreement was found between the measured depth of cracks and a 2-D elastic-plastic finite element stress analysis

  7. Impact of HFIR LEU Conversion on Beryllium Reflector Degradation Factors

    Energy Technology Data Exchange (ETDEWEB)

    Ilas, Dan [ORNL

    2013-10-01

    An assessment of the impact of low enriched uranium (LEU) conversion on the factors that may cause the degradation of the beryllium reflector is performed for the High Flux Isotope Reactor (HFIR). The computational methods, models, and tools, comparisons with previous work, along with the results obtained are documented and discussed in this report. The report documents the results for the gas and neutronic poison production, and the heating in the beryllium reflector for both the highly enriched uranium (HEU) and LEU HFIR configurations, and discusses the impact that the conversion to LEU may have on these quantities. A time-averaging procedure was developed to calculate the isotopic (gas and poisons) production in reflector. The sensitivity of this approach to different approximations is gauged and documented. The results show that the gas is produced in the beryllium reflector at a total rate of 0.304 g/cycle for the HEU configuration; this rate increases by ~12% for the LEU case. The total tritium production rate in reflector is 0.098 g/cycle for the HEU core and approximately 11% higher for the LEU core. A significant increase (up to ~25%) in the neutronic poisons production in the reflector during the operation cycles is observed for the LEU core, compared to the HEU case, for regions close to the core s horizontal midplane. The poisoning level of the reflector may increase by more than two orders of magnitude during long periods of downtime. The heating rate in the reflector is estimated to be approximately 20% lower for the LEU core than for the HEU core. The decrease is due to a significantly lower contribution of the heating produced by the gamma radiation for the LEU core. Both the isotopic (gas and neutronic poisons) production and the heating rates are spatially non-uniform throughout the beryllium reflector volume. The maximum values typically occur in the removable reflector and close to the midplane.

  8. Analysis of features of the deformation of auxetic beryllium

    OpenAIRE

    Гунько, Михаил Николаевич; Олейнич-Лысюк, Алла Васильевна; Раранский, Николай Дмитриевич; Тащук, Александр Юрьевич

    2015-01-01

    In the framework of the linear elasticity theory using the experimentally obtained elastic stiffness modules, temperature dependences of the elastic compliance modules and tensor components of Poisson's ratios    of beryllium in a wide range of temperatures and directions in the crystal lattice were calculated, and it was shown that with increasing temperature, the value and signs of Poisson's ratios  change differently in various temperature intervals. In the interval 0-300K,  become negativ...

  9. Towards limits of excitation energy in the reaction 3He(1.8 GeV) + natAg

    International Nuclear Information System (INIS)

    Hot nuclei are studied, where through an appropriate choice of incident channel and event selection, dynamical effects are attenuated and multifragmentation is limited. Three preparatory results are given, the 3He(1.8 GeV) + natAg can be described using an intranuclear cascade, INC, model; through a suitable selection of events a limit of the excitation energy that a nucleus can absorb without breaking into large pieces is given, it is shown that corresponding alpha decay is consistent with an evaporative process. (K.A.)

  10. Multifragmentation in the 4.8-GeV 3He+ natAg, 197Au reactions

    International Nuclear Information System (INIS)

    Multifragmentation of natAg and 197Au nuclei induced by a 4.8-GeV 3He ions has been studied with the Indiana Silicon Sphere 4π detector array. Rapidity and moving source analyses are consistent with thermal emission from a source in approximate kinetic equilibrium. For the most dissipative collisions, the spectral Coulomb peaks are broadened to very low energies, indicative of emission from an extended nuclear system. Predictions of a model with an intranuclear cascade and an expanding, emitting source compare well with experimental multiplicity distributions and the evolution of fragment spectral shapes

  11. Multifragmentation in the 4.8-GeV {sup 3}He+ {sup nat}Ag, {sup 197}Au reactions

    Energy Technology Data Exchange (ETDEWEB)

    Kwiatkowski, K.; Morley, K.B.; Foxford, E.R.; Bracken, D.S.; Viola, V.E.; Yoder, N.R.; Legrain, R.; Pollacco, E.C.; Volant, C.; Friedman, W.A.; Korteling, R.G.; Brzychczyk, J.; Breuer, H. [Department of Chemistry and Physics and IUCF, Indiana University, Bloomington, Indiana 47405 (United States)]|[Commissariat a l`Energie Atomique DAPNIA/Service de Physique des Particles, Centre d`Etudes de Saclay, 91191 Gif-sur-Yvette Cedex (France)]|[Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1SG (Canada)]|[Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)]|[Institute of Physics, Jagiellonian University, 30-059 Krakow (Poland)]|[Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

    1995-05-08

    Multifragmentation of {sup nat}Ag and {sup 197}Au nuclei induced by a 4.8-GeV {sup 3}He ions has been studied with the Indiana Silicon Sphere 4{pi} detector array. Rapidity and moving source analyses are consistent with thermal emission from a source in approximate kinetic equilibrium. For the most dissipative collisions, the spectral Coulomb peaks are broadened to very low energies, indicative of emission from an extended nuclear system. Predictions of a model with an intranuclear cascade and an expanding, emitting source compare well with experimental multiplicity distributions and the evolution of fragment spectral shapes.

  12. Dose Rates from Plutonium Metal and Beryllium Metal in a 9975 Shipping Container

    International Nuclear Information System (INIS)

    A parametric study was performed of the radiation dose rates that might be produced if plutonium metal and beryllium metal were shipped in the 9975 shipping package. These materials consist of heterogeneous combinations plutonium metal and beryllium. The plutonium metal content varies up to 4.4 kilograms while the beryllium metal varies up to 4 kilograms. This paper presents the results of that study

  13. Study of the reactions resulting in heavy fragment formation in the collisions 40Ar + Cu, Ag and Au at 8 to 115 MeV/u

    International Nuclear Information System (INIS)

    This work concerns the study of nuclear collisions showing a heavy fragment in 40Ar + Cu, Ag and Au from 8 A MeV to 115 A MeV. The reactions are classified by centrality or collision violence via the multiplicity of charged particles detected in a 4π array. For the most peripheral reactions (low multiplicities) we always find a projectile-like fragment with velocity near to that of the beam and a heavy target-like fragment with very small velocity. For the more central collisions we find the well-known incomplete fusion reactions at 17 and 27 A MeV. Above 27 A MeV two groups of very dissipative reactions are observed, both with high charged particle multiplicities. The first reaction group forms several fragments with Z ≤ 10 and average longitudinal velocity near to that of c.m. These are very rare, and are found only for the highest 1% of multiplicities. They produce a heavy fragment and a forward spray (θ≤60 angle) of particles with charge going from 1 to ≅13. The momentum carried out by the spray is randomly spread over all the particles. In spite of the increase of momentum carried by this spray with increasing beam energy, a heavy emission source is formed with 1 - 2 GeV of excitation energy. After a phase of expansion, especially signaled by Z = 1 particles, this source then evaporates many particles. Finally we observed the remaining heavy residual nucleus. (author)

  14. Elastic, micro- and macroplastic properties of polycrystalline beryllium

    Science.gov (United States)

    Kardashev, B. K.; Kupriyanov, I. B.

    2011-12-01

    The Young's modulus and the internal friction of beryllium polycrystals (size grain from 6 to 60 μm) prepared by the powder metallurgy method have been studied as functions of the amplitude and temperature in the range from 100 to 873 K. The measurements have been performed using the composite piezoelectric vibrator method for longitudinal vibrations at frequencies about 100 kHz. Based on the acoustic measurements, the data have been obtained on the elastic and inelastic (microplastic) properties as functions of vibration stress amplitudes within the limits from 0.2 to 30-60 MPa. The microplastic deformation diagram is shown to become nonlinear at the amplitudes higher than 5 MPa. The beryllium mechanical characteristics (the yield strength σ 0.2, the ultimate strength σ u , and the conventional microscopic yield strength σ y ) obtained with various grain sizes are compared. At room temperature, all the parameters satisfactorily obey the Hall-Petch relationship, although there is no complete similarity. The temperature dependences are quite different, namely: σ 0.2( T) and σ u ( T) decrease monotonically during heating from room temperature to higher temperatures; however, σ y ( T) behaves unusually, and it has a minimum near 400 K. The different levels of stresses and the absence of similarity indicate that the scattering of the ultrasound energy and the formation of a level of the macroscopic flow stresses in beryllium occur on dislocation motion obstacles of different origins.

  15. Electron microscope study of thin beryllium lamellae (1963)

    International Nuclear Information System (INIS)

    Thin SR beryllium lamellae are examined by electron microscopy after various treatments, together with other samples made up of Be - Fe at 1 per cent and 0.2 per cent iron. The SR beryllium is examined after annealing at 750 deg C and 900 deg C, strongly cold-worked and quenched at 900 deg C. At 950 deg C the metal is perfectly annealed; at 750 deg C the polygonisation is almost complete, the dislocations are arranged either is dislocation walls in the prismatic planes, or in hexagonal lattices with non-dissociated nodes suggesting a high stacking defect energy. The cold-worked structure has a high dislocation density and already existing crystal walls. In the quenched state, the few dislocations are very straight and are aligned in the crystallographic directions. Iron-precipitation is studied in two alloys during tempering at 660 deg after quenching in salt water. The precipitate appears at the grain boundaries and then spreads through the matrix leaving a depleted zone in the neighbourhood of the joints. These precipitates, in the form of platelets parallel to the base planes of the beryllium lattice have been identified as the inter metallic phase Be11 Fe oriented in relation to the matrix (0 0 0 1)//(0 0 0 1) (1 0 1-bar 0)//(1 1 2-bar 0). (authors)

  16. Cascade Wittig reaction-double Claisen and Cope rearrangements: one-pot synthesis of diprenylated coumarins gravelliferone, balsamiferone, and 6,8-diprenylumbelliferone

    Digital Repository Service at National Institute of Oceanography (India)

    Patre, R.E.; Shet, J.B.; Parameswaran, P.S.; Tilve, S.G.

    ) Majik, M. S.; Parameswaran, P. S.; Tilve, S. G. J. Org. Chem. 2009, 74, 3591. (b) Patre, R. E.; Gawas, S.; Parameswaran, P. S; Tilve, S. G. Tetrahedron Lett. 2007, 48, 3517. (c) Desai, V. G.; Manekar-Tilve, A. S.; Tilve, S. G. Synth. Commun. 1996, 29... version: Tetrahedron Lett.: 50(47); 2009; 6488–6490 Cascade Wittig reaction-double Claisen & Cope rearrangements: one-pot synthesis of diprenylated coumarins gravelliferone, balsamiferone and 6,8-diprenylumbelliferone Rupesh E. Patre aѱ , Jyoti B...

  17. 298 K rate coefficients for the reaction of OH with i - C3H7I, n - C3H7I and C3H8

    OpenAIRE

    Carl, S. A.; J. N. Crowley

    2001-01-01

    The kinetics of the title reactions were investigated using the laser photolysis - resonance fluorescence method, employing the sequential two-photon dissociation of NO2 in the presence of H2  as the OH source. The 298 K rate constant for OH + C3H8 was found to be (1.15 ± 0.1) × 10-12 cm3 s-1, in excellent agreement with the literature recommendation, and with a separate determination using HNO3  photolysis at 248 nm as the OH source. The 298 K rate constant...

  18. Factorization of the Cross Section for the 12C(p,pα)8Be(g.s.) Reaction at an Incident Energy of 100 MeV

    International Nuclear Information System (INIS)

    Cross sections and analyzing powers for the reaction 12C(p,pα)8Be at an incident energy of 100 MeV, measured over a range of quasifree scattering angle pairs, are compared with elastic scattering of protons from 4He. Remarkable agreement between angular distributions of the two sets of data, presented as a function of the scattering angle in the two-body centre-of mass, is found. Thus the α-cluster reacts to the projectile just like a free particle.

  19. Beryllium Science: US-UK agreement on the use of Atomic Energy for mutual defense

    Energy Technology Data Exchange (ETDEWEB)

    Hanafee, J.E. (ed.)

    1988-02-19

    Twenty-seven papers are presented on beryllium supply, production, fabrication, safe handling, analysis, powder technology, and coatings. Separate abstracts have been prepared for the individual papers. (DLC)

  20. The impact of beryllium chloride and oxide on sexual function and offspring development in female rats

    International Nuclear Information System (INIS)

    The comparative study of the action of soluble chloride and difficultly soluble beryllium oxide on sexual cycle in female rats and their conception capability, revealing of embryotoxic and teratogenic effect of these compounds and determination of significance of terms of their impact on pregnant female as well as beryllium capability to penetrate through the placenta and accumulate in the offspring organism have been performed. A great potential danger of impact on animal reproductive function of soluble (chloride) beryllium compounds as compared with low soluble ones (oxide). In the genesis of embryotoxic teratonic effect probably along with beryllium impact on progeny through the maternal organism there occurs its direct impact on the offspring

  1. Vacuum Brazing of Beryllium Copper Components for the National Ignition Facility

    International Nuclear Information System (INIS)

    A process for vacuum brazing beryllium copper anode assemblies was required for the Plasma Electrode Pockels Cell System, or PEPC, a component for the National Ignition Facility (NIF). Initial problems with the joint design and wettability of the beryllium copper drove some minor design changes. Brazing was facilitated by plating the joint surface of the beryllium copper rod with silver 0.0006 inch thick. Individual air sampling during processing and swipe tests of the furnace interior after brazing revealed no traceable levels of beryllium

  2. Beryllium Science: US-UK agreement on the use of Atomic Energy for mutual defense

    International Nuclear Information System (INIS)

    Twenty-seven papers are presented on beryllium supply, production, fabrication, safe handling, analysis, powder technology, and coatings. Separate abstracts have been prepared for the individual papers

  3. Problems and future plan on material development of beryllium in materials testing reactors

    International Nuclear Information System (INIS)

    Beryllium has been utilized as a moderator and/or reflector in a number of material testing reactors. The attractive nuclear properties of beryllium are its low atomic number, low atomic weight, low parasitic capture cross section for thermal neutrons, readiness to part with one of its own neutrons, and good neutron elastic scattering characteristics. However, it is difficult to reprocess irradiated beryllium because of high induced radioactivity. Disposal has also been difficult because of toxicity issues and special nuclear material controls. In this paper, problems and future plans of beryllium technology are introduced for nuclear reactors. (author)

  4. Thermal decomposition of beryllium perchlorate tetrahydrate

    International Nuclear Information System (INIS)

    Thermal decomposition of Be(ClO4)2x4H2O was studied by the differential flow technique in the helium stream. The kinetics was followed by an exchange reaction of the perchloric acid appearing by the decomposition with potassium carbonate. The rate of CO2 liberation in this process was recorded by a heat conductivity detector. The exchange reaction yielding CO2 is quantitative, it is not the limiting one and it does not distort the kinetics of the process of perchlorate decomposition. The solid products of decomposition were studied by infrared and NMR spectroscopy, roentgenography, thermography and chemical analysis. A mechanism suggested for the decomposition involves intermediate formation of hydroxyperchlorate: Be(ClO4)2x4H2O → Be(OH)ClO4+HClO4+3H2O; Be(OH)ClO4 → BeO+HClO4. Decomposition is accompained by melting of the sample. The mechanism of decomposition is hydrolytic. At room temperature the hydroxyperchlorate is a thick syrup-like compound crystallizing after long storing

  5. Chemokine regulation in response to beryllium exposure in human peripheral blood mononuclear and dendritic cells

    International Nuclear Information System (INIS)

    Exposure to beryllium (Be) induces a delayed-type hypersensitivity immune reaction in the lungs of susceptible individuals, which leads to the onset of Be sensitivity and Chronic Beryllium Disease (CBD). Although some mechanistic aspects of CBD have begun to be characterized, very little is known about the molecular mechanisms by which Be activates the host immune response. To gain insight into the cellular response to Be exposure, we have performed global microarray analysis using a mixture of peripheral blood mononuclear and dendritic cells (PBMC/DCs) from a non-CBD source to identify genes that are specifically upregulated in response to BeSO4 stimulation, compared to a control metal salt, Al2(SO4)3. We identified a number of upregulated immunomodulatory genes, including several chemokines in the MIP-1 and GRO families. Using PBMC/DCs from three different donors, we demonstrate that BeSO4 stimulation generally exhibits an increased rate of both chemokine mRNA transcription and release compared to Al2(SO4)3 exposure, although variations among the individual donors do exist. We show that MIP-1α and MIP-1β neutralizing antibodies can partially inhibit the ability of BeSO4 to stimulate cell migration of PBMC/DCs in vitro. Finally, incubation of PBMC/DCs with BeSO4 altered the binding of the transcription factor RUNX to the MIP-1α promoter consensus sequence, indicating that Be can regulate chemokine gene activation. Taken together, these results suggest a model in which Be stimulation of PBMC/DCs can modulate the expression and release of different chemokines, leading to the migration of lymphocytes to the lung and the formation of a localized environment for development of Be disease in susceptible individuals

  6. Chloro({2-[mesityl(quinolin-8-yl-κNboryl]-3,5-dimethyl-phenyl}methyl-κCpalladium(II as a Catalyst for Heck Reactions

    Directory of Open Access Journals (Sweden)

    Sem Raj Tamang

    2015-07-01

    Full Text Available We recently reported an air and moisture stable 16-electron borapalladacycle formed upon combination of 8-quinolyldimesitylborane with bis(benzonitriledichloropalladium(II. The complex features a tucked mesityl group formed upon metalation of an ortho-methyl group on a mesityl; however it is unusually stable due to contribution of the boron pz orbital in delocalizing the carbanion that gives rise to an η4-boratabutadiene fragment coordinated to Pd(II, as evidenced from crystallographic data. This complex was observed to be a highly active catalyst for the Heck reaction. Data of the catalyst activity are presented alongside data found in the literature, and initial comparison reveals that the borapalladacycle is quite active. The observed catalysis suggests the borapalladacycle readily undergoes reductive elimination; however the Pd(0 complex has not yet been isolated. Nevertheless, the ambiphilic ligand 8-quinolyldimesitylborane may be able to support palladium in different redox states.

  7. Chloro({2-[mesityl(quinolin-8-yl-κN)boryl]-3,5-dimethyl-phenyl}methyl-κC)palladium(II) as a catalyst for Heck reactions.

    Science.gov (United States)

    Tamang, Sem Raj; Hoefelmeyer, James D

    2015-01-01

    We recently reported an air and moisture stable 16-electron borapalladacycle formed upon combination of 8-quinolyldimesitylborane with bis(benzonitrile)dichloropalladium(II). The complex features a tucked mesityl group formed upon metalation of an ortho-methyl group on a mesityl; however it is unusually stable due to contribution of the boron pz orbital in delocalizing the carbanion that gives rise to an η4-boratabutadiene fragment coordinated to Pd(II), as evidenced from crystallographic data. This complex was observed to be a highly active catalyst for the Heck reaction. Data of the catalyst activity are presented alongside data found in the literature, and initial comparison reveals that the borapalladacycle is quite active. The observed catalysis suggests the borapalladacycle readily undergoes reductive elimination; however the Pd(0) complex has not yet been isolated. Nevertheless, the ambiphilic ligand 8-quinolyldimesitylborane may be able to support palladium in different redox states. PMID:26193250

  8. Analysis and characterization of heavy residues produced in 129Xe + natSn reactions between 8 and 25 AMeV

    International Nuclear Information System (INIS)

    Studies with the INDRA multidetector of the 129Xe + natSn reactions showed the unexpected existence of heavy fragments with a charge as large as Z=70. The charges of Xe and Sn are 54 and 50 respectively. Reactions between nuclei with a charge product greater than 2700 are dominated by deep inelastic collisions. For Xe + Sn the product is exactly 2700. After these observations, 129Xe + natSn reactions at 8, 12, 15, 20 and 25 AMeV have been done. It will then be possible to clarify if the heavy residues are formed by an incomplete fusion, massive transfers occurring in deep inelastic collisions or a very asymmetric fission of a compound system. This work will present experimental results obtained by the analysis of these experiments. We will show that heavy residues are formed with a production cross-section of 10-2 mb. Angular distributions show that the residues can be produced by an incomplete fusion of the projectile and the target. The study of the products in coincidence with the residues shows that a compound system was formed, followed by a fission producing the residue and a lighter fragment. The comparison with a phenomenological model, HIPSE, confirms that the model is valid at these energies

  9. Erosion simulation of first wall beryllium armour under ITER transient heat loads

    International Nuclear Information System (INIS)

    The beryllium is foreseen as plasma facing armour for the first wall in the ITER in form of Be-clad blanket modules in macrobrush design with brush size about 8-10 cm. In ITER significant heat loads during transient events (TE) are expected at the main chamber wall that may leads to the essential damage of the Be armour. The main mechanisms of metallic target damage remain surface melting and melt motion erosion, which determines the lifetime of the plasma facing components. Melting thresholds and melt layer depth of the Be armour under transient loads are estimated for different temperatures of the bulk Be and different shapes of transient loads. The melt motion damages of Be macrobrush armour caused by the tangential friction force and the Lorentz force are analyzed for bulk Be and different sizes of Be-brushes. The damage of FW under radiative loads arising during mitigated disruptions is numerically simulated.

  10. Erosion simulation of first wall beryllium armour after ITER transient heat loads and runaway electrons action

    International Nuclear Information System (INIS)

    Beryllium is foreseen as plasma facing armour for the first wall (FW) in ITER in form of Be-clad blanket modules in macrobrush design with brush size about 8-10 cm. In ITER significant heat loads during transient events (TE) and runaway electrons impact are expected at the main chamber wall that may leads to the essential damage of the Be armour. The main mechanisms of metallic target damage remain surface melting, evaporation, and melt motion, which determine the life-time of the plasma facing components. The melt motion damages of Be macrobrush armour caused by the tangential friction force and the J x B forces are analyzed for bulk Be and different sizes of Be-brushes. The damage of the FW due to heat loads caused by runaway electrons is numerically simulated.

  11. Generalized Lenard-Balescu calculations of electron-ion temperature relaxation in beryllium plasma.

    Science.gov (United States)

    Fu, Zhen-Guo; Wang, Zhigang; Li, Da-Fang; Kang, Wei; Zhang, Ping

    2015-09-01

    The problem of electron-ion temperature relaxation in beryllium plasma at various densities (0.185-18.5g/cm^{3}) and temperatures [(1.0-8)×10^{3} eV] is investigated by using the generalized Lenard-Balescu theory. We consider the correlation effects between electrons and ions via classical and quantum static local field corrections. The numerical results show that the electron-ion pair distribution function at the origin approaches the maximum when the electron-electron coupling parameter equals unity. The classical result of the Coulomb logarithm is in agreement with the quantum result in both the weak (Γ_{ee}1) electron-electron coupling ranges, whereas it deviates from the quantum result at intermediate values of the coupling parameter (10^{-2}future inertial confinement fusion experiments involving Be plasma. PMID:26465571

  12. Quantum Monte Carlo calculation of the binding energy of the beryllium dimer

    International Nuclear Information System (INIS)

    The accurate calculation of the binding energy of the beryllium dimer is a challenging theoretical problem. In this study, the binding energy of Be2 is calculated using the diffusion Monte Carlo (DMC) method, using single Slater determinant and multiconfigurational trial functions. DMC calculations using single-determinant trial wave functions of orbitals obtained from density functional theory calculations overestimate the binding energy, while DMC calculations using Hartree-Fock or CAS(4,8), complete active space trial functions significantly underestimate the binding energy. In order to obtain an accurate value of the binding energy of Be2 from DMC calculations, it is necessary to employ trial functions that include excitations outside the valence space. Our best estimate DMC result for the binding energy of Be2, obtained by using configuration interaction trial functions and extrapolating in the threshold for the configurations retained in the trial function, is 908 cm−1, only slightly below the 935 cm−1 value derived from experiment

  13. Production of various sizes and some properties of beryllium pebbles by the rotating electrode method

    Energy Technology Data Exchange (ETDEWEB)

    Iwadachi, T.; Sakamoto, N.; Nishida, K. [NGK Insulators Ltd., Nagoya (Japan); Kawamura, H.

    1998-01-01

    The particle size distribution of beryllium pebbles produced by the rotating electrode method was investigated. Particle size depends on some physical properties and process parameters, which can practicaly be controlled by varying electrode angular velocities. The average particle sizes produced were expressed by the hyperbolic function with electrode angular velocity. Particles within the range of 0.3 and 2.0 mm in diameter are readily produced by the rotating electrode method while those of 0.2 mm in diameter are also fabricable. Sphericity and surface roughness were good in each size of pebble. Grain sizes of the pebbles are 17 {mu} m in 0.25 mm diameter pebbles and 260 {mu} m in 1.8 mm diameter pebbles. (author)

  14. Immunological characterisation of groups of people exposed to beryllium as a result of burning coal with high contents of this toxin

    International Nuclear Information System (INIS)

    An epidemological study was made of persons occupationally (39) and non-occupationally (34) exposed to relatively low concentrations of beryllium in air as a result of coal combustion. Beryllium concentrations in the workplace were between 30 and 800x10-5 mg.m-3, and in the town of Sokolov 1.68-0.39x10-5 mg.m-3. Radial immunodiffusion was used to determine main immunoglobulin classes, and the passive haemagglutination reaction used to determine antibodies (lungs, heart, liver, spleen, thyroid) and antibodies to nuclear (ANA) and mitochondrial (AMA) antigens in intact rat lungs and rats with experimental berylliosis. In both exposed groups significant increase in IgG and IgA and autoantibodies was found compared with controls (60). Specific AMA and ANA were found in exposed groups (higher values in women). (UK)

  15. Investigation of the fission fragment properties of the reaction sup 2 sup 3 sup 8 U(n,f) at incident neutron energies up to 5.8 MeV

    CERN Document Server

    Vivès, F; Bax, H; Oberstedt, S

    2000-01-01

    The fission fragment properties of the reaction sup 2 sup 3 sup 8 U(n,f) have been studied, at different incident neutron energies ranging from E sub n =1.2 to 5.8 MeV. The pre-neutron emission mass, kinetic energy and fission fragment angular distributions have been investigated with a double Frisch-gridded ionization chamber. The influence of the subthreshold vibrational resonances and of the proton pairing effect on the fission fragment properties is clearly visible. The total kinetic energy averaged over all fission fragment masses TKEbar shows an increasing trend up to E sub n =3.5 MeV with a sudden drop at roughly E sub n =3.8 MeV which has been attributed to the onset of pair breaking at the barrier. Above E sub n =3.8 MeV, the TKEbar is again continuously increasing. The changes in the mass yield and TKEbar(A) distributions have been studied as a function of the compound nuclear excitation energy and their contribution to the observed variations in the TKEbar have been determined. The two-dimensional ...

  16. One-electron reactions of 1,5- and 1,8-dihydroxy-9,10-anthraquinones: a pulse radiolysis study

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Haridas; Palit, D.K.; Mukherjee, Tulsi; Mittal, J.P. (Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.)

    1991-04-21

    Absorption characteristics of the semiquinone free radicals formed by the one-electron reduction (using e{sub aq}{sup -}, Co{sub 2}{sup .-} and CH{sub 3}C radical OHCH{sub 3} as the reductant) as well as the oxidation (using OH{sup .}, O{sup .-} and N{sub 3}{sup .} as the oxidants) of 1,5-dihydroxy-9,10-anthraquinone (1,5-DHAQ) and 1,8-dihydroxy-9,10-anthraquinone (1,8-DHAQ) have been studied by pulse radiolysis in pure isopropyl alcohol and in aqueous solutions containing various appropriate additives. The first acid dissociation constants for the reduced semiquinones were measured as pK{sub a} = 3.65 and 3.95 for 1,5-DHAQ and 1,8-DHAQ, respectively. Second-order rate constants for various formation and decay reactions have been determined. The one-electron reduction potentials (vs. NHE) were determined at pH 11, as E{sub 11}{sup 1} = -350 mV (for 1,5-DHAQ) and E{sub 11}{sup 1} = -377 mV (for 1,8-DHAQ), respectively. Differences with 1,4-dihydroxy-9,10-anthraquinone (quinizarin) are discussed. (author).

  17. One-electron reactions of 1,5- and 1,8-dihydroxy-9,10-anthraquinones: a pulse radiolysis study

    International Nuclear Information System (INIS)

    Absorption characteristics of the semiquinone free radicals formed by the one-electron reduction (using eaq-, Co2.- and CH3C radical OHCH3 as the reductant) as well as the oxidation (using OH., O.- and N3. as the oxidants) of 1,5-dihydroxy-9,10-anthraquinone (1,5-DHAQ) and 1,8-dihydroxy-9,10-anthraquinone (1,8-DHAQ) have been studied by pulse radiolysis in pure isopropyl alcohol and in aqueous solutions containing various appropriate additives. The first acid dissociation constants for the reduced semiquinones were measured as pKa = 3.65 and 3.95 for 1,5-DHAQ and 1,8-DHAQ, respectively. Second-order rate constants for various formation and decay reactions have been determined. The one-electron reduction potentials (vs. NHE) were determined at pH 11, as E111 = -350 mV (for 1,5-DHAQ) and E111 = -377 mV (for 1,8-DHAQ), respectively. Differences with 1,4-dihydroxy-9,10-anthraquinone (quinizarin) are discussed. (author)

  18. Proceedings of the third IEA international workshop on beryllium technology for fusion

    International Nuclear Information System (INIS)

    This report is the Proceedings of the Third International Energy Agency International Workshop on Beryllium Technology for Fusion. The workshop was held on October 22-24, 1997, at the Sangyou Kaikan in Mito City with 68 participants who attended from the Europe, the Russian Federation, the Kazakstan, the United States and Japan. The topics for papers were arranged into 9 sessions; beryllium applications for ITER, production and characterization, chemical compatibility and corrosion, forming and joining, plasma/tritium interactions, beryllium coating, first wall applications, neutron irradiation effects, health and safety. To utilize beryllium in the pebble type blanket, a series of discussions were intensified in multiple view points such as the swelling, He/T release from beryllium pebble irradiated up to high He content, effective thermal conductivity, tritium permeation and coating, and fabrication cost, and so on. As the plasma facing material, life time of beryllium and coated beryllium, dust and particle production, joining, waste treatment, mechanical properties and deformation by swelling were discussed as important issues. Especially, it was recognized throughout the discussions that the comparative study by the different researchers should be carried out to establish the reliability of the data reported in the workshop and in others. To enhance the comparative study, the world wide collaboration for the relative evaluation of the beryllium was proposed by the International Organization Committee and the proposal was approved by all of the participants. The 45 of the presented papers are indexed individually. (J.P.N.)

  19. Theoretical Chemistry to assess the risk from the Beryllium in ITER

    International Nuclear Information System (INIS)

    The Bestair project was recently awarded the IRSN prize for creativity in exploratory research. The objective of this study was to assess the potential release of beryllium, an extremely toxic element, into the environment in the event of an accident through improved knowledge of the beryllium-based chemical forms present inside the ITER containment. (author)

  20. Tritium release from highly neutron irradiated constrained and unconstrained beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Chakin, V., E-mail: vladimir.chakin@kit.edu; Rolli, R.; Vladimirov, P.; Moeslang, A.

    2015-06-15

    Highlights: • For the irradiated constrained beryllium pebbles, the tritium release occurs easier than for the unconstrained ones. • Tritium retention in the irradiated constrained and unconstrained beryllium pebbles decreases with increasing irradiation temperature. • Formation of sub-grains in the constrained beryllium pebbles facilitate the open porosity network formation. - Abstract: Beryllium is the reference neutron multiplier material in the Helium Cooled Pebble Bed (HCPB) breeding blanket of fusion power plants. Significant tritium inventory accumulated in beryllium as a result of neutron-induced transmutations could become a safety issue for the operation of such blankets as well as for the nuclear waste utilization. To provide a related materials database, a neutron irradiation campaign of beryllium pebbles with diameters of 0.5 and 1 mm at 686–1006 K, the HIDOBE-01 experiment, has been performed in the HFR in Petten, the Netherlands, producing up to 3020 appm helium and 298 appm tritium. Thermal desorption tests of irradiated unconstrained and constrained beryllium pebbles were performed in a purge gas flow using a quadrupole mass-spectrometer (QMS) and an ionization chamber. Compared to unconstrained pebbles, constrained beryllium pebbles have an enhanced tritium release at all temperatures investigated. Small elongated sub-grains formed under irradiation in the constrained pebbles promote formation of numerous channels for facilitated tritium release.

  1. Reduction evaporation of BeO to provide a beryllium metal sample for accelerator radiometric dating

    International Nuclear Information System (INIS)

    A technique is described for preparing beryllium metal samples from beryllium oxide for use in accelerator ion sources. These samples are used to measure minute 10Be/9Be ratios for radiometric dating at the University of Washington tandem Van de Graaff accelerator. (orig.)

  2. Proceedings of the third IEA international workshop on beryllium technology for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hiroshi; Okamoto, Makoto [eds.

    1998-01-01

    This report is the Proceedings of the Third International Energy Agency International Workshop on Beryllium Technology for Fusion. The workshop was held on October 22-24, 1997, at the Sangyou Kaikan in Mito City with 68 participants who attended from the Europe, the Russian Federation, the Kazakstan, the United States and Japan. The topics for papers were arranged into 9 sessions; beryllium applications for ITER, production and characterization, chemical compatibility and corrosion, forming and joining, plasma/tritium interactions, beryllium coating, first wall applications, neutron irradiation effects, health and safety. To utilize beryllium in the pebble type blanket, a series of discussions were intensified in multiple view points such as the swelling, He/T release from beryllium pebble irradiated up to high He content, effective thermal conductivity, tritium permeation and coating, and fabrication cost, and so on. As the plasma facing material, life time of beryllium and coated beryllium, dust and particle production, joining, waste treatment, mechanical properties and deformation by swelling were discussed as important issues. Especially, it was recognized throughout the discussions that the comparative study by the different researchers should be carried out to establish the reliability of the data reported in the workshop and in others. To enhance the comparative study, the world wide collaboration for the relative evaluation of the beryllium was proposed by the International Organization Committee and the proposal was approved by all of the participants. The 45 of the presented papers are indexed individually. (J.P.N.)

  3. Tritium release from highly neutron irradiated constrained and unconstrained beryllium pebbles

    International Nuclear Information System (INIS)

    Highlights: • For the irradiated constrained beryllium pebbles, the tritium release occurs easier than for the unconstrained ones. • Tritium retention in the irradiated constrained and unconstrained beryllium pebbles decreases with increasing irradiation temperature. • Formation of sub-grains in the constrained beryllium pebbles facilitate the open porosity network formation. - Abstract: Beryllium is the reference neutron multiplier material in the Helium Cooled Pebble Bed (HCPB) breeding blanket of fusion power plants. Significant tritium inventory accumulated in beryllium as a result of neutron-induced transmutations could become a safety issue for the operation of such blankets as well as for the nuclear waste utilization. To provide a related materials database, a neutron irradiation campaign of beryllium pebbles with diameters of 0.5 and 1 mm at 686–1006 K, the HIDOBE-01 experiment, has been performed in the HFR in Petten, the Netherlands, producing up to 3020 appm helium and 298 appm tritium. Thermal desorption tests of irradiated unconstrained and constrained beryllium pebbles were performed in a purge gas flow using a quadrupole mass-spectrometer (QMS) and an ionization chamber. Compared to unconstrained pebbles, constrained beryllium pebbles have an enhanced tritium release at all temperatures investigated. Small elongated sub-grains formed under irradiation in the constrained pebbles promote formation of numerous channels for facilitated tritium release

  4. Protection of beryllium metal against microbial influenced corrosion using silane self-assembled monolayers

    Science.gov (United States)

    Vaidya, Rajendra U.; Deshpande, Alina; Hersman, Larry; Brozik, Susan M.; Butt, Darryl

    1999-08-01

    The effectiveness of a self-assembled silane monolayer as protection for beryllium against microbiologically influenced corrosion (MIC) was demonstrated. Four-point bend tests on coated and uncoated beryllium samples were conducted after microbiological exposures, and the effectiveness of these coatings as MIC protection was reported through mechanical property evaluations. Application of the silane monolayer to the beryllium surfaces was found to prevent degradation of the failure strength and displacement-to-failure of beryllium in bending. In contrast, the uncoated beryllium samples exhibited a severe reduction in these mechanical properties in the presence of the marine Pseudomonas bacteria. The potentiodynamic measurements showed that both the uncoated and coated samples pitted at the open-circuit potential. However, the size and distribution of the corrosion pits formed on the surface of the beryllium samples were significantly different for the various cases (coated vs uncoated samples exposed to control vs inoculated medium). This study demonstrates the following: (1) the deleterious effects of MIC on the mechanical properties of beryllium and (2) the potential for developing fast, easy, and cost-effective MIC protection for beryllium metal using silane self-assemblies.

  5. Reduction of surface erosion caused by helium blistering in sintered beryllium and sintered aluminum powder

    International Nuclear Information System (INIS)

    Studies have been conducted to find materials with microstructures which minimize the formation of blisters. A promising class of materials appears to be sintered metal powder with small average grain sizes and low atomic number Z. Studies of the surface erosion of sintered aluminum powder (SAP 895) and of aluminum held at 4000C due to blistering by 100 keV helium ions have been conducted and the results are compared to those obtained earlier for room temperature irradiation. A significant reduction of the erosion rate in SAP 895 in comparison to annealed aluminum and SAP 930 is observed. In addition results on the blistering of sintered beryllium powder (type I) irradiated at room temperature and 6000C by 100 keV helium ions are given. These results will be compared with those reported recently for vacuum cast beryllium foil and a foil of sintered beryllium powder (type II) which was fabricated differently, than type I. For room temperature irradiation only a few blisters could be observed in sintered beryllium powder type I and type II and they are smaller in size and in number than in vacuum cast beryllium. For irradiation at 6000C large scale exfoliation of blisters was observed for vacuum cast beryllium but much less exfoliation was seen for sintered beryllium powder, type I, and type II. The results show a reduction in erosion rate cast beryllium, for both room temperature and 6000C

  6. 20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

    Science.gov (United States)

    2010-04-01

    ... this section), together with lung pathology consistent with chronic beryllium disease, including the...) Occupational or environmental history, or epidemiologic evidence of beryllium exposure; and (ii) Any three of...) Lung pathology consistent with chronic beryllium disease. (D) Clinical course consistent with a...

  7. Formation of an intramolecular cystine disulfide during the reaction of 8-azidoguanosine 5'-triphosphate with cytosolic phosphoenolpyruvate carboxykinase (GTP) causes inactivation without photolabeling

    International Nuclear Information System (INIS)

    Phosphoenolpyruvate carboxykinase (GTP) (PEPCK) specifically utilizes a guanosine or inosine nucleotide as a substrate, yet it does not share extended sequence homology with other GTP-binding proteins, and the molecular basis for its nucleotide specificity is not understood. In an effort to locate the enzyme's nucleotide-binding site, the authors have studied the interaction of cytosolic PEPCK from rat liver with the photoprobe 8-azidoGTP, which fulfills the criteria of a specific photoaffinity label for PEPCK. The photoprobe binds reversibly to the enzyme prior to modification and at low concentrations causes greater than 60% inactivation-GTP provides nearly complete protection against inactivation by 8-azidoGTP, whereas phosphoenolpyruvate and metal ions provide partial protection. In addition, the photoprobe is a substrate for the enzyme and has a Km similar to that for GTP. However, the extent of covalent modification by [32P]8-azido-GTP as measured by three independent techniques is significantly lower than the extent of enzyme inactivation. Further investigation of this anomaly has revealed that the loss in enzymatic activity is caused by modification of a critical cysteine residue in a reaction that does not terminate with covalent attachment of the photolabel. Quantitation of the total free thiols of modified PEPCK shows that 2 mol of cysteine is lost per mole of inactivated enzyme. These results indicate that the photoinactivation of PEPCK by 8-azidoGTP is caused by the formation of an intramolecular cystine disulfide bridge, thus providing evidence for the existence of a pair of proximal cysteine residues within the GTP-binding site. The interaction of cysteine residues with the reactive photogenerated derivatives of 8-azidopurines is discussed

  8. High-spin structures in sup 1 sup 0 sup 8 sup , sup 1 sup 1 sup 0 Pd isotopes produced in fusion/fission reactions

    CERN Document Server

    Lalkovski, S; Porquet, M

    2002-01-01

    High-spin states in sup 1 sup 0 sup 8 sup , sup 1 sup 1 sup 0 Pd isotopes are studied by gamma-ray spectroscopy of heavy-ion induced fission. The Pd isotopes were produced in the fission channel of the sup 3 sup 1 P + sup 1 sup 7 sup 6 Yb reaction at beam energy 152 MeV. The prompt gamma-rays are detected with the EUROBALL4 multidetector array. The level scheme of sup 1 sup 0 sup 8 Pd was extended with a new negative parity band. In sup 1 sup 1 sup 0 Pd the yrast sequence was observed up to spin I=14 sup + and negative parity bands have been identified. The excitation energy ratio E(4 sup +)/E(2 sup +) for the sup 1 sup 0 sup 8 sup , sup 1 sup 1 sup 0 Pd isotopes is 2.42 and 2.46 respectively, which is close to 2.5 predicted for an O(6) transitional gamma-soft rotor. The band-crossing in these Pd isotopes is assigned to a low-OMEGA subnu sub h sub 1 sub 1 sub / sub 2 configuration. The negative parity states arise from two neutron configurations: nu h sub 1 sub 1 sub / sub 2 x nu g sub 7 sub / sub 2 and nu h ...

  9. Preliminary irradiation test for new material selection on lifetime extension of beryllium reflector

    International Nuclear Information System (INIS)

    Beryllium has been utilized as a moderator and/or reflector in Japan Materials Testing Reactor (JMTR), because of nuclear properties of beryllium, low neutron capture and high neutron scattering cross sections. At present, the amount of irradiated beryllium frames in JMTR is about 2 tons in the JMTR canal. In this study, preliminary irradiation test was performed from 162nd to 165th operation cycles of JMTR as irradiation and PIE technique development for lifetime expansion of beryllium frames. The design study of irradiation capsule, development of dismount device of irradiation capsule and the high accuracy size measurement device were carried out. The PIEs such as tensile tests, metallurgical observation, and size change measurement were carried out with two kinds of irradiated beryllium metals (S-200F and S-65C)

  10. Preliminary irradiation test for new material selection on lifetime extension of beryllium reflector

    International Nuclear Information System (INIS)

    Beryllium has been utilized as a moderator and/or reflector in Japan Materials Testing Reactor (JMTR), because of nuclear properties of beryllium, low neutron capture and high neutron scattering cross sections. At present, the amount of irradiated beryllium frames in JMTR is about 2 tons in the JMTR canal. In this study, preliminary irradiation test was performed from 162nd to 165th operation cycles of JMTR as irradiation and PIE technique development for lifetime expansion of beryllium frames. The design study of irradiation capsule, development of dismount device of irradiation capsule and the high accuracy size measurement device were carried out. The PIEs such as tensile tests, metallurgical observation, and size change measurement were also carried out with two kinds of irradiated beryllium metals (S-200F and S-65C). (author)

  11. Deformation behaviour of fine grained high purity beryllium - influence of fabrication parameters, temperature and copper additions

    International Nuclear Information System (INIS)

    The deformation behaviour of high-purity beryllium was tested on hot isostatically pressed samples of different initial grain size and compared with material manufactured commercially from pure beryllium and with beryllium-copper alloys containing 0.44, 1.1 and 2.1 at.% copper. Initial grain size of these high purity material was 0C. Grain structure of the samples was subsequently analysed by light, rastor and transmission electron microscopy. The influence of copper additions on deformation of high-purity beryllium was analysed. A further aim of this study was to investigate, by suitable methods, the mode of action of relevant impurities and to throw light on their influence on grain formation. This should enable reliable information to be provided for the manufacture of high-purity beryllium which, in turn, will lead to an improvement in ductility. (orig./IHOE)

  12. Use of notched beams to establish fracture criteria for beryllium

    International Nuclear Information System (INIS)

    The fracture of an improved form of pure beryllium was studied under triaxial tensile stresses. This state of stress was produced by testing notched beams, which were thick enough to be in a state of plane strain at the center. A plane strain, elastic-incremental plasticity finite element program was then used to determine the stress and strain distributions at fracture. A four-point bend fixture was used to load the specimens. It was carefully designed and manufactured to eliminate virtually all of the shear stresses at the reduced section of the notched beams. The unixial properties were obtained

  13. Accumulation of tritium in beryllium material under neutron irradiation

    International Nuclear Information System (INIS)

    In the present work the programming code is created on the basis of which the accumulation kinetics of tritium and isotope of He4 in the Be9 sample is analyzed depending on the time. The program is written in C++ programming language and for the calculations Monte Carlo method was applied. This program scoped on the calculation of concentration of helium and tritium in beryllium samples depending on the spectrum of the neutron flux in different experimental reactors such as JMTR, JOYO and IPEN/MB. The processes of accumulation of helium and tritium for each neutron energy spectrum of these reactors were analyzed. (author)

  14. Atomic, Crystal, Elastic, Thermal, Nuclear, and Other Properties of Beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, A

    2006-02-01

    This report is part of a series of documents that provide a background to those involved in the construction of beryllium components and their applications. This report is divided into five sub-sections: Atomic/Crystal Structure, Elastic Properties, Thermal Properties, Nuclear Properties, and Miscellaneous Properties. In searching through different sources for the various properties to be included in this report, inconsistencies were at times observed between these sources. In such cases, the values reported by the Handbook of Chemistry and Physics was usually used. In equations, except where indicated otherwise, temperature (T) is in degrees Kelvin.

  15. Double K-shell photoionization of atomic beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Yip, F. L. [Departamento de Quimica, Modulo 13, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Martin, F. [Departamento de Quimica, Modulo 13, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Instituto Madrilen(tilde sign)o de Estudios Avanzados en Nanociencia, Cantoblanco, E-28049 Madrid (Spain); McCurdy, C. W. [Department of Chemistry, University of California, Davis, California 95616 (United States); Lawrence Berkeley National Laboratory, Chemical Sciences, and Ultrafast X-ray Science Laboratory, Berkeley, California 94720 (United States); Rescigno, T. N. [Lawrence Berkeley National Laboratory, Chemical Sciences, and Ultrafast X-ray Science Laboratory, Berkeley, California 94720 (United States)

    2011-11-15

    Double photoionization of the core 1s electrons in atomic beryllium is theoretically studied using a hybrid approach that combines orbital and grid-based representations of the Hamiltonian. The {sup 1} S ground state and {sup 1} P final state contain a double occupancy of the 2s valence shell in all configurations used to represent the correlated wave function. Triply differential cross sections are evaluated, with particular attention focused on a comparison of the effects of scattering the ejected electrons through the spherically symmetric valence shell with similar cross sections for helium, representing a purely two-electron target with an analogous initial-state configuration.

  16. Electromagnetic properties of the Beryllium-11 nucleus in Halo EFT

    OpenAIRE

    Hammer H.-W.; Phillips D.R.

    2010-01-01

    We compute electromagnetic properties of the Beryllium-11 nucleus using an effective field theory that exploits the separation of scales in this halo system. We fix the parameters of the EFT from measured data on levels and scattering lengths in the 10Be plus neutron system. We then obtain predictions for the B(E1) strength of the 1/2+ to 1/2− transition in the 11Be nucleus. We also compute the charge radius of the ground state of 11Be. Agreement with experiment within the expected accurac...

  17. Microstructure and mechanical properties of neutron irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Ishitsuka, E.; Kawamura, H. [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Terai, T.; Tanaka, S.

    1998-01-01

    Microstructure and mechanical properties of the neutron irradiated beryllium with total fast neutron fluences of 1.3 - 4.3 x 10{sup 21} n/cm{sup 2} (E>1 MeV) at 327 - 616degC were studied. Swelling increased by high irradiation temperature, high fluence, and by the small grain size and high impurity. Obvious decreasing of the fracture stress was observed in the bending test and in small grain specimens which had many helium bubbles on the grain boundary. Decreasing of the fracture stress for small grain specimens was presumably caused by crack propagation on the grain boundaries which weekend by helium bubbles. (author)

  18. Dosage of boron traces in graphite, uranium and beryllium oxide

    International Nuclear Information System (INIS)

    The problem of the dosage of the boron in the materials serving to the construction of nuclear reactors arises of the following way: to determine to about 0,1 ppm close to the quantities of boron of the order of tenth ppm. We have chosen the colorimetric analysis with curcumin as method of dosage. To reach the indicated contents, it is necessary to do a previous separation of the boron and the materials of basis, either by extraction of tetraphenylarsonium fluoborate in the case of the boron dosage in uranium and the beryllium oxide, either by the use of a cations exchanger resin of in the case of graphite. (M.B.)

  19. Tritium analyses of COBRA-1A2 beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, D.L. [Pacific Northwest National Lab., Richland, WA (United States)

    1998-03-01

    Selected tritium measurements have been completed for the COBRA-1A2 experiment C03 and D03 beryllium pebbles. The completed results, shown in Tables 1, 2, and 3, include the tritium assay results for the 1-mm and 3-mm C03 pebbles, and the 1-mm D03 pebbles, stepped anneal test results for both types of 1-mm pebbles, and the residual analyses for the stepped-anneal specimens. All results have been reported with date-of-count and are not corrected for decay. Stepped-anneal tritium release response is provided in addenda.

  20. Three-particle continuum and α-decay of high excited states of 8Be in the 10B(dα) reaction at Ed=48 MeV

    International Nuclear Information System (INIS)

    Results of investigation into three-particle d+10B→α+α+α reaction under Ed=48 MeV are presented. The reaction analysis performed points out to a possible contribution of 8Be nucleus highly excited state decay processes with E*≥32 MeV. 5 refs., 3 figs., 1 tab

  1. Energy Spectra And Angular Distributions Of Imfs Produced In 8-gev Proton And 12-gev Proton And Ne-20 Induced Multifragmentation Reactions (the First Results Of The Kek-ps E393 And Nirs 11p052 Experiments)

    CERN Document Server

    Tanaka, K H; Murakami, T; Ito, H; Yasuda, K; Murata, J; Muramatsu, R; Tanaka, Y J; Hirai, Y; Miyazaki, K; Tanaka, Y; Nagasaka, Y; Haseno, M; Okuno, Y; Ushie, K; Hara, H; Tsuji, S; Satake, K; Kimura, K; Kubohara, R; Shibata, Y; Kosuge, F; Nakai, K; Ochiisi, H; Kouda, S; Nakamura, H; Morinobu, S; Sugaya, Y; Ohkuma, Y; Takada, E

    2000-01-01

    Energy Spectra And Angular Distributions Of Imfs Produced In 8-gev Proton And 12-gev Proton And Ne-20 Induced Multifragmentation Reactions (the First Results Of The Kek-ps E393 And Nirs 11p052 Experiments)

  2. Fluoroindenes. Communication 8. Synthesis of polyfluoroindenes containing chlorine in the aromatic ring, by dehalogenation of the products of reaction of 1-chlorononafluoroindan with LiCl

    International Nuclear Information System (INIS)

    The authors examine the reaction of (II) with lithium chloride in order to obtain indans containing chlorine in the aromatic ring and in the 1 position. These indans have been used to synthesize several polyfluoroindenes with chlorine in the six-membered ring. The assignment of the 19F NMR spectral signals for the indans obtained was carried out by analogy with other polyfluoroindans. Worthy of note is the occurrence of doublet splitting of the F7 signals with J/sub F-F//sup 1,7/ 5-6 Hz, and the triplet signals for F4 with J/sub F-F//sup 3,4/ ∼ 7-8 Hz in the spectra. The values of the constants may be readily found when the F/sup 4,7/ atoms are not adjacent to the dimethylamino group. The reaction of 1-chlorononafluoroindan with lithium chloride gives 1,5- and 1,6- dichlorooctafluoroindans and 1,5,6-trichloroheptafluoroindan. Dehalogenation of the resulting indans gives polyfluoroindenes containing chlorine in the aromatic ring. Treatment of these polyfluoroindenes with aluminum chloride gives 1,1,3,5- and 1,1,3,6-tetrachlorotetrafluoroindenes and 1,1,3,5,6-pentachlorotrifluoroindene

  3. On the 6A 1 ← 4T 1 luminescence of Fe 3+ in disordered nanocrystalline LiGa 5O 8 prepared by a combustion reaction

    Science.gov (United States)

    Riesen, Hans

    2008-08-01

    A combustion reaction yields nanocrystalline LiGa 5O 8 in the inverse-spinel phase ( Fd3 m) in contrast to previous attempts by quenching microcrystalline powders from 1350 °C. This follows from XRD, IR and luminescence spectra of Fe 3+ at 298, 78 and 2.5 K. The ordered phase is obtained by calcination at 900 °C of the combustion product. The Fe 3+ luminescence is assigned to the 6A 1(S) ← 4T 1(G) transition of ions in tetrahedral sites in both polymorphs; this is confirmed by the similar behaviour of the 4A 2(F) ← 4T 1(P) luminescence of Co 2+ upon the order-disorder transition. The variation of the luminescence spectra is explained in terms of inhomogeneity and the Td → C3 symmetry reduction.

  4. Search for W and Z bosons in the reaction anti-p p ---> 2 jets + gamma at s**(1/2) = 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Florida U. /UC, Santa Barbara /Fermilab

    2005-07-01

    The authors present a study of the dijet invariant mass distribution for the reaction {bar p}p {yields} 2 jets+{gamma} + X, at a center of mass energy of 1.8 TeV, using data collected by the CDF experiment. They compare the data to predictions for the production of a photon with two jets, together with the resonant processes {bar p}p {yields} W/Z + {gamma} + X, in which the W and Z bosons decay hadronically. A fit is made to the dijet invariant mass distribution combining the non-resonant background and resonant processes. They use the result to establish a limit for the inclusive production cross section of W/Z + {gamma} with hadronic decay of the W and Z bosons.

  5. Physicochemical characteristics of aerosol particles generated during the milling of beryllium silicate ores: implications for risk assessment.

    Science.gov (United States)

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

    2008-01-01

    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 concentrations among these industries. Understanding the physicochemical properties of exposure aerosols may help to understand the differential immunopathologic mechanisms of sensitization and CBD and lead to more biologically relevant exposure standards. Properties of aerosols generated during the industrial milling of bertrandite and beryl ores were evaluated. Airborne beryllium mass concentrations among work areas ranged from 0.001 microg/m(3) (beryl ore grinding) to 2.1 microg/m(3) (beryl ore crushing). Respirable mass fractions of airborne beryllium-containing particles were 80% in high-energy input areas (beryl melting, beryl grinding). Particle specific surface area decreased with processing from feedstock ores to drumming final product beryllium hydroxide. Among work areas, beryllium was identified in three crystalline forms: beryl, poorly crystalline beryllium oxide, and beryllium hydroxide. In comparison to aerosols generated by high-CBD risk primary production processes, aerosol particles encountered during milling had similar mass concentrations, generally lower number concentrations and surface area, and contained no identifiable highly crystalline beryllium oxide. One possible explanation for the apparent low prevalence of CBD among workers exposed to beryllium mineral dusts may be that characteristics of the exposure material do not contribute to the development of lung burdens sufficient for progression from sensitization to CBD. In comparison to high-CBD risk exposures where the chemical nature of aerosol

  6. Measurement of the efficient cross section of the reaction {sup 7}Be(p, {gamma}){sup 8}B at low energies and implications in the problem of solar neutrinos; Mesures de la section efficace de la reaction {sup 7}Be(p,{gamma}){sup 8}B a basses energies et implications dans le probleme des neutrinos solaires

    Energy Technology Data Exchange (ETDEWEB)

    Hammache, Fairouz

    1999-07-01

    The {sup 8}B produced inside the sun through the reaction {sup 7}Be(p,{gamma}){sup 8}B is the main, and even unique, source of high energy neutrinos detected in most solar neutrino detection experiments, except with Gallex and Sage. These experiments have all measured a neutrinos flux lower than the one predicted by solar models. Several explanations have been proposed to explain this deficit, but all require a precise knowledge of the efficient cross-section of the reaction {sup 7}Be(p,{gamma}){sup 8}B, because the neutrinos flux of {sup 8}B is directly proportional to this reaction. The direct measurement of this cross section for the solar energy is impossible because of its low value (about 1 femto-barn). In order to get round this problem, the cross sections are measured at higher energy and extrapolated to the solar energy using a theoretical energy dependence. The 6 previous experimental determinations of the efficient cross section were shared in two distinct groups with differences of about 30% which leads to an uncertainty of the same order on the high energy neutrinos flux. The re-measurement of the cross section of this reaction with a better precision is thus of prime importance. A direct measurement of the cross section in the energy range comprised between 0.35 and 1.4 MeV (cm) has been performed first. These experiments have permitted the precise measurement of each parameter involved in the determination of the cross section. Then, measurements of the cross section have been carried out with the PAPAP accelerator at 185.8, 134.7 and 111.7 keV, the lowest mass center energy never reached before. The results are in excellent agreement with those obtained at higher energies. The value obtained by extrapolation of these data for the astrophysical factor S{sub 17}(0) is 19.21.3 EV-B, which leads to a significant reduction of the uncertainty on the high energy neutrinos flux of {sup 8}B. (J.S.)

  7. Factorization of the cross section for the 12C (p,pα)8Be(g.s.) reaction at an incident energy of 100 MeV

    International Nuclear Information System (INIS)

    Knockout reactions present a direct and convenient method for the study of cluster structure in the ground state of atomic nuclei. In a-cluster knockout by means of projectiles such as energetic protons and ci-particles, distorted-wave impulse approximation (DWIA) theory is able to provide a reasonably good representation of experimental data. However, there arc indications that the reaction process may be viewed as being even simpler than implied by the full DWIA theory. For example, if spin-orbit interactions arc ignored in a (p,pa) reaction, the coincidence cross section may be formulated to display its separate observable quantities as explicit factors. This factorized expression of the coincidence cross section is written as equation in which Ep and Eα are kinetic energies of the light ejectiles, Sα is a spectroscopic factor, Fk is a kinematic factor, a half-shell two-body cross section that describes the scattering of the projectile from the bound α-cluster, and ψ is related to the bound-state wave function. Factorization would also hold if the recoiling heavy residue acts merely as spectator to the collision between the projectile and the cluster. Previous results of Roos at al. [1] for 12C(p,pα)8Be at an incident energy of 100 McV suggest a breakdown of the factorization approximation. In this work on the same target and incident energy, we explore a larger range of two-body scattering angles, which allows a better determination of the general trend. As shown in the figure, the angular distribution of the cross section for the two-body projectile-bound a-cluster system (shown as solid circles), extracted from the coincidence cross section is in remarkable agreement with classic scattering of protons from 4He (solid curve) at the same incident energy. Consequently the factorization approximation is valid to a surprising extent for this knockout reaction. Implications of this result will be discussed.(author)

  8. 4{pi} studies of the 1.8{endash}4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. I. Energy deposition

    Energy Technology Data Exchange (ETDEWEB)

    Morley, K.B.; Kwiatkowski, K.; Bracken, D.S.; Renshaw Foxford, E.; Viola, V.E.; Woo, L.W.; Yoder, N.R. [Departments of Chemistry and Physics and Indiana University Cyclotron Facility, Indiana University, Bloomington, Indiana 47405 (United States); Legrain, R.; Pollacco, E.C.; Volant, C. [Commissariat a l`Energie Atomique, DAPNIA Service de Physique Nucleaire, C.E. Saclay, 91191 Gir-sur-Yvette Cedex (France); Korteling, R.G. [Department of Chemistry, Simon Fraser University, Burnaby, British Columbia (Canada); Breuer, H. [University of Maryland, College Park, Maryland 20742 (United States); Brzychczyk, J. [Institute of Physics, Jagiellonian University, 30-059 Krakow (Poland)

    1996-08-01

    The Indiana Silicon Sphere 4{pi} detector has been used to measure light-charged particles and intermediate-mass fragments (IMFs) emitted in the 18{endash}4.8 GeV {sup 3}He+{sup nat}Ag, {sup 197}Au reactions. Ejectile multiplicity and total event kinetic energy distributions scale systematically with projectile energy and target mass, except for the {sup nat}Ag target at 3.6 and 4.8 GeV. For this system, a saturation in deposition energy is indicated by the data, suggesting the upper projectile energy for stopping has been reached. Maximum deposition energies of {approximately}950 MeV for the {sup nat}Ag target and {approximately}1600 MeV for the {sup 197}Au target are inferred from the data. The results also demonstrate the importance of accounting for fast cascade processes in defining the excitation energy of the targetlike residue. Correlations between various observables and the average IMF multiplicity indicate that the total thermal energy and total observed charge provide useful gauges of the excitation energy of the fragmenting system. Comparison of the experimental distributions with intranuclear cascade predictions shows qualitative agreement. {copyright} {ital 1996 The American Physical Society.}

  9. 曝气生物滤池处理高氨氮含铍废水研究%Treatment of Beryllium Containing Wastewater with High Ammonia Concentration by Biological Aerated Filters

    Institute of Scientific and Technical Information of China (English)

    孙芳; 孙卫玲

    2012-01-01

    含铍废水具有较高的毒性,目前关于其处理方法的研究较少.文章针对铍冶炼废水中铍超标以及高氨氮浓度的问题,选取接种有微生物的曝气生物滤池(BAF)工艺同时去除氨氮和铍,并分析其去除铍的机理.反应器系统的长期运行结果表明,BAF对高氨氮含铍废水具有较好的处理效果.在进水氨氮浓度200 mg/L,铍浓度50~100μg/L,停留时间24h条件下,处理出水氨氮浓度稳定在1.8~10.0 mg/L,铍浓度小于5μg/L.BAF主要通过系统中的微生物去除铍,载体对铍的吸附量较小,用Langmuir模型对吸附数据进行拟合,得到微生物对铍的吸附容量为684.9 μg/g.形态提取实验表明,被微生物去除的铍主要以有机结合态存在,且微生物细胞表面对铍的吸附量有限,大量的铍富集于微生物细胞内,为此,BAF对铍有长期稳定的处理效果.%Beryllium-containing waste water is of high toxicity, but there are limited researches concerning its treatment. Beryllium smelting wastewater contains high concentrations of beryllium and ammonia. Biological aerated filters (BAF), which was inoculated with microorganisms, was used to treat beryllium smelting wastewater, and the mechanisms involved were investigated. Results show that BAF could remove beryllium and ammonia simultaneously. When influent concentrations of ammonia nitrogen and beryllium were 200 mg/L and 50-100 μg/L respectively, HRT was 24 h, the concentration ammonia was in the range of 1.8~10.0 mg/L, and beryllium concentration was less than 5 μg/L in the effluent. The removal of beryllium was mainly attributed to the microorganisms in BAF, and the maximum uptake of beryllium by microorganisms calculated by Langmuir equation was 684.9 μg/g. The beryllium removed by BAF was mainly combined to organic fraction. Moreover, large amount of beryllium accumulated inside the cell with limited biosorption by the external surface of microorganisms. Therefore, high removal

  10. Effect of copper on crack propagation in beryllium single crystals

    International Nuclear Information System (INIS)

    The effect of copper additives on the fracture energy and the development of cracks parallel to the basal plane was studied in zone-refined single crystalline beryllium. At 770K the cleavage planes are very smooth, so the crack propagation energy, which is independent of copper content (less than 2 at. percent Cu) in the range of measurement accuracy, is only a little higher than the surface energy of the basal plane. At room temperature, due to intense plastic processes taking place in front of the crack tip, the fracture energy is an order of magnitude higher than at low temperatures. The effect of copper on the plastic processes can be divided into two regions. In region I (less than 1.2 at. percent Cu), in which the crack propagation energy increases sharply with increasing copper content, crack propagation is controlled by prism slips. The decrease in crack propagation energy in region II (greater than 1.2 at. percent Cu) can be attributed to a reduction of beryllium twinning energy with increasing copper content. (auth)

  11. Calculations for electron-impact excitation and ionization of beryllium

    CERN Document Server

    Zatsarinny, Oleg; Fursa, Dmitry V; Bray, Igor

    2016-01-01

    The B-spline R-matrix and the convergent close-coupling methods are used to study electron collisions with neutral beryllium over an energy range from threshold to 100 eV. Coupling to the target continuum significantly affects the results for transitions from the ground state, but to a lesser extent the strong transitions between excited states. Cross sections are presented for selected transitions between low-lying physical bound states of beryllium, as well as for elastic scattering, momentum transfer, and ionization. The present cross sections for transitions from the ground state from the two methods are in excellent agreement with each other, and also with other available results based on nonperturbative convergent pseudo-state and time-dependent close-coupling models. The elastic cross section at low energies is dominated by a prominent shape resonance. The ionization from the $(2s2p)^3P$ and $(2s2p)^1P$ states strongly depends on the respective term. The current predictions represent an extensive set o...

  12. Influence of neutron irradiation on the tritium retention in beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Rolli, R.; Ruebel, S.; Werle, H. [Forschungszentrum Karlsruhe, Inst. fuer Neutronenphysik und Reaktortechnik, Karlsruhe (Germany); Wu, C.H.

    1998-01-01

    Carbon-based materials and beryllium are the candidates for protective layers on the components of fusion reactors facing plasma. In contact with D-T plasma, these materials absorb tritium, and it is anticipated that tritium retention increases with the neutron damage due to neutron-induced traps. Because of the poor data base for beryllium, the work was concentrated on it. Tritium was loaded into the samples from stagnant T{sub 2}/H{sub 2} atmosphere, and afterwards, the quantity of the loaded tritium was determined by purged thermal annealing. The specification of the samples is shown. The samples were analyzed by SEM before and after irradiation. The loading and the annealing equipments are contained in two different glove boxes with N{sub 2} inert atmosphere. The methods of loading and annealing are explained. The separation of neutron-produced and loaded tritium and the determination of loaded tritium in irradiated samples are reported. Also the determination of loaded tritium in unirradiated samples is reported. It is evident that irradiated samples contained much more loaded tritium than unirradiated samples. The main results of this investigation are summarized in the table. (K.I.)

  13. The 3He(alpha, gamma)7Be reaction rate, solar 7Be and 8B neutrino fluxes, and the production of 7Li during the Big Bang

    International Nuclear Information System (INIS)

    The 3He(α,γ)7Be reaction plays an important role both in determining the predicted fluxes of 7Be and 8B neutrinos from our Sun, and in the calculation of primordial 7Li production. In light of the highly precise determination of the baryon-to-photon ratio from the cosmic microwave background data, it is necessary to re-determine primordial 7Li production. Recent experimental nuclear astrophysics work has led to an improved determination of the 3He(α,γ)7Be cross section, with several experiments clustered at E = 0.5 MeV center-of-mass energy and above [2, and references therein]. On the other hand, precisely calibrated 7Be and 8B neutrino fluxes from the Sun are now available. Assuming the accepted solar central temperature to be correct, the neutrino flux data can be used to determine the 3He(α,γ)7Be cross section at the solar Gamow peak, E = 0.03 MeV. The energy range relevant for Big Bang 7Li production lies just between 0.03 and 0.5 MeV. The poster aims to use the two above described levels in order to improve the precision of the predicted primordial abundance of 7Li. It updates a previous work that appeared before the new cross section, solar neutrino and microwave background data were available. (author)

  14. Effect of material strength on the relationship between the principal Hugoniot and quasi-isentrope of beryllium and 6061-T6 aluminum below 35 GPa

    International Nuclear Information System (INIS)

    Quasi-isentropic (QI) compression can be achieved by loading a specimen with a low strain rate, long rise time uniaxial strain wave. Recent experimental data show that the quasi-isentrope of 6061-T6 aluminum lies a few percent above the principal Hugoniot, that is, at a given specific volume, the QI stress exceeds the principal Hugoniot stress. It has been suggested that this effect is due to material strength. Using Hugoniot data, shock-reshock, and shock-unload data for beryllium and 6061-T6 aluminum, we have constructed the quasi-isentropes as functions of specific volume. Our results show that the QI stress exceeds the principal Hugoniot stress above a Hugoniot stress of 8.4 GPa in beryllium, and between Hugoniot stresses of 3.8 and 21.4 GPa in aluminum. The effect is due to strength and implies that the QI yield strength can be large. Our calculations show that the QI yield strength is 0.9 GPa in aluminum at a QI stress of 9 GPa, and 5.2 GPa in beryllium at a QI stress of 35 GPa

  15. Reduction of surface erosion caused by helium blistering: comparison between vacuum-cast and sintered-beryllium

    International Nuclear Information System (INIS)

    The blister formation and the erosion associated with blistering in a vacuum cast beryllium foil and in a foil of sintered beryllium powder have been investigated for irradiation at room temperature and at 6000C with 100 keV 4He+ ions for total doses of 0.5 to 1.0 C cm-2. For room temperature irradiation the blisters in sintered beryllium powder are smaller in size than in vacuum cast beryllium. For irradiation at 6000C large scale exfoliation of blisters was observed for vacuum cast beryllium but only small amount of exfoliation was seen for sintered beryllium powder. The results show a reduction in erosion rate in sintered beryllium as compared to the erosion rate in vacuum cast beryllium. For room temperature irradiation no erosion rate could be determined for the sintered beryllium foil since no blister exfoliation was observed. For 6000C irradiation the erosion rate for sintered beryllium foil is more than an order of magnitude smaller than for vacuum cast beryllium

  16. Investigation of the fission fragment properties of the reaction 238U(n,f) at incident neutron energies up to 5.8 MeV

    International Nuclear Information System (INIS)

    The fission fragment properties of the reaction 238U(n,f) have been studied, at different incident neutron energies ranging from En=1.2 to 5.8 MeV. The pre-neutron emission mass, kinetic energy and fission fragment angular distributions have been investigated with a double Frisch-gridded ionization chamber. The influence of the subthreshold vibrational resonances and of the proton pairing effect on the fission fragment properties is clearly visible. The total kinetic energy averaged over all fission fragment masses TKEbar shows an increasing trend up to En=3.5 MeV with a sudden drop at roughly En=3.8 MeV which has been attributed to the onset of pair breaking at the barrier. Above En=3.8 MeV, the TKEbar is again continuously increasing. The changes in the mass yield and TKEbar(A) distributions have been studied as a function of the compound nuclear excitation energy and their contribution to the observed variations in the TKEbar have been determined. The two-dimensional mass-TKE distributions have been described in terms of fission modes and compared with theoretical calculations performed recently in the frame of the multi-modal random neck-rupture model. Although theoretically six asymmetric fission modes are predicted which all surpass individual outer barriers, an interpretation in terms of only two asymmetric modes has physical meaning. This points to an influence of shell structure effects to the observed distributions. In any case, the super-long symmetric mode has to be included, in order to explain the dip in TKEbar(A) distribution close to symmetry

  17. Investigation of the fission fragment properties of the reaction 238U(n,f) at incident neutron energies up to 5.8 MeV

    Science.gov (United States)

    Vivès, F.; Hambsch, F.-J.; Bax, H.; Oberstedt, S.

    2000-01-01

    The fission fragment properties of the reaction 238U(n,f) have been studied, at different incident neutron energies ranging from En=1.2 to 5.8 MeV. The pre-neutron emission mass, kinetic energy and fission fragment angular distributions have been investigated with a double Frisch-gridded ionization chamber. The influence of the subthreshold vibrational resonances and of the proton pairing effect on the fission fragment properties is clearly visible. The total kinetic energy averaged over all fission fragment masses ( overlineTKE) shows an increasing trend up to En=3.5 MeV with a sudden drop at roughly En=3.8 MeV which has been attributed to the onset of pair breaking at the barrier. Above En=3.8 MeV, the overlineTKE is again continuously increasing. The changes in the mass yield and overlineTKE( A) distributions have been studied as a function of the compound nuclear excitation energy and their contribution to the observed variations in the overlineTKE have been determined. The two-dimensional mass-TKE distributions have been described in terms of fission modes and compared with theoretical calculations performed recently in the frame of the multi-modal random neck-rupture model. Although theoretically six asymmetric fission modes are predicted which all surpass individual outer barriers, an interpretation in terms of only two asymmetric modes has physical meaning. This points to an influence of shell structure effects to the observed distributions. In any case, the super-long symmetric mode has to be included, in order to explain the dip in overlineTKE( A) distribution close to symmetry.

  18. Immobilisation of beryllium in solid waste (red-mud) by fixation and vitrification.

    Science.gov (United States)

    Bhat, P N; Ghosh, D K; Desai, M V M

    2002-01-01

    The objective of this study was to obtain information on the immobilization of beryllium (Be) in solid waste generated in the extraction process of beryllium from its ore, Beryl. This solid waste, termed red-mud, contains oxides of iron, aluminium, calcium, magnesium and beryllium. The red-mud waste contains beryllium at levels above the permissible limit, which prevents its disposal as solid waste. The total beryllium content in the red-mud analysed showed value ranging from 0.39 to 0.59% Be The studies showed that 50% of the total beryllium in red-mud can be extracted by water by repeated leaching over a period of 45 days. The cement mix, casting into cement blocks, was subjected to leachability studies over a period of 105 days and immobilization factor (IF factor) was determined. These IF values, of the order of 102, were compared with those obtained by performing leachability study on vitrified red-mud masses produced at different temperature conditions. Direct heating of the red-mud gave the gray coloured, non-transparent vitreous mass (as 'bad glass') showed effective immobilisation factor for beryllium in red-mud of the order of 10(4). PMID:12092765

  19. New and Emerging Technologies for Real-Time Air and Surface Beryllium Monitoring; FINAL

    International Nuclear Information System (INIS)

    In this study, five emerging technologies were identified for real-time monitoring of airborne beryllium: Microwave-Induced Plasma Spectroscopy (MIPS), Aerosol Beam-Focused Laser-Induced Plasma Spectroscopy (ABFLIPS), Laser-Induced Breakdown Spectroscopy (LIBS), Surfaced-Enhanced Raman Scattering (SERS) Spectroscopy, and Micro-Calorimetric Spectroscopy (CalSpec). Desired features of real-time air beryllium monitoring instrumentation were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies as well as their unique demonstrated capability to provide real-time monitoring of similar materials. However, best available technologies were considered, regardless of their ability to comply with the desired features. None of the five technologies have the capability to measure the particle size of airborne beryllium. Although reducing the total concentration of airborne beryllium is important, current literature suggests that reducing or eliminating the concentration of respirable beryllium is critical for worker health protection. Eight emerging technologies were identified for surface monitoring of beryllium. CalSpec, MIPS, SERS, LIBS, Laser Ablation, Absorptive Stripping Voltametry (ASV), Modified Inductively Coupled Plasma (ICP) Spectroscopy, and Gamma BeAST. Desired features of real-time surface beryllium monitoring were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies. However, the best available technologies were considered regardless of their ability to comply with the desired features

  20. New and Emerging Technologies for Real-Time Air and Surface Beryllium Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, B.E. Jr.; Churnetski, E.L.; Cooke, L.E.; Reed, J.J.; Howell, M.L.; Smith, V.D.

    2001-09-01

    In this study, five emerging technologies were identified for real-time monitoring of airborne beryllium: Microwave-Induced Plasma Spectroscopy (MIPS), Aerosol Beam-Focused Laser-Induced Plasma Spectroscopy (ABFLIPS), Laser-Induced Breakdown Spectroscopy (LIBS), Surfaced-Enhanced Raman Scattering (SERS) Spectroscopy, and Micro-Calorimetric Spectroscopy (CalSpec). Desired features of real-time air beryllium monitoring instrumentation were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies as well as their unique demonstrated capability to provide real-time monitoring of similar materials. However, best available technologies were considered, regardless of their ability to comply with the desired features. None of the five technologies have the capability to measure the particle size of airborne beryllium. Although reducing the total concentration of airborne beryllium is important, current literature suggests that reducing or eliminating the concentration of respirable beryllium is critical for worker health protection. Eight emerging technologies were identified for surface monitoring of beryllium. CalSpec, MIPS, SERS, LIBS, Laser Ablation, Absorptive Stripping Voltametry (ASV), Modified Inductively Coupled Plasma (ICP) Spectroscopy, and Gamma BeAST. Desired features of real-time surface beryllium monitoring were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies. However, the best available technologies were considered regardless of their ability to comply with the desired features.

  1. The development and advantages of beryllium capsules for the National Ignition Facility

    International Nuclear Information System (INIS)

    Capsules with beryllium ablators have long been considered as alternatives to plastic for the National Ignition Facility laser; now the superior performance of beryllium is becoming well substantiated. Beryllium capsules have the advantages of relative insensitivity to instability growth, low opacity, high tensile strength, and high thermal conductivity. 3-D calculation with the HYDRA code NTIS Document No. DE-96004569 (M. M. Marinak et.al. in UCRL-LR-105821-95-3) confirm 2-D LASNEX U. B. Zimmerman and W. L. Kruer, Comments Plasmas Phys. Controlled Thermonucl. Fusion, 2, 51(2975) results that particular beryllium capsule designs are several times less sensitive than the CH point design to instability growth from DT ice roughness. These capsule designs contain more ablator mass and leave some beryllium unablated at ignition. By adjusting the level of copper dopant, the unablated mass can increase or decrease, with a corresponding decrease or increase in sensitivity to perturbations. A plastic capsule with the same ablator mass as the beryllium and leaving the same unablated mass also shows this reduced perturbation sensitivity. Beryllium's low opacity permits the creation of 250 eV capsule designs. Its high tensile strength allows it to contain DT fuel at room temperature. Its high thermal conductivity simplifies cryogenic fielding

  2. Mechanical compression tests of beryllium pebbles after neutron irradiation up to 3000 appm helium production

    Energy Technology Data Exchange (ETDEWEB)

    Chakin, V., E-mail: vladimir.chakin@kit.edu [Karlsruhe Institute of Technology, Institite for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Rolli, R.; Moeslang, A. [Karlsruhe Institute of Technology, Institite for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Zmitko, M. [The European Joint Undertaking for ITER and the Development of Fusion Energy, c/Josep Pla, no. 2, Torres Diagonal Litoral, Edificio B3, 08019 Barcelona (Spain)

    2015-04-15

    Highlights: • Compression tests of highly neutron irradiated beryllium pebbles have been performed. • Irradiation hardening of beryllium pebbles decreases the steady-state strain-rates. • The steady-state strain-rates of irradiated beryllium pebbles exceed their swelling rates. - Abstract: Results: of mechanical compression tests of irradiated and non-irradiated beryllium pebbles with diameters of 1 and 2 mm are presented. The neutron irradiation was performed in the HFR in Petten, The Netherlands at 686–968 K up to 1890–2950 appm helium production. The irradiation at 686 and 753 K cause irradiation hardening due to the gas bubble formation in beryllium. The irradiation-induced hardening leads to decrease of steady-state strain-rates of irradiated beryllium pebbles compared to non-irradiated ones. In contrary, after irradiation at higher temperatures of 861 and 968 K, the steady-state strain-rates of the pebbles increase because annealing of irradiation defects and softening of the material take place. It was shown that the steady-state strain-rates of irradiated beryllium pebbles always exceed their swelling rates.

  3. Theoretical investigation on the interaction between beryllium, magnesium and calcium with benzene, coronene, cirumcoronene and graphene

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • The binding energies between benzene and Be, Mg and Ca are 1.8, 2.3 and 3.2 kcal/mol. • The alkaline earth complexes with benzene favor the non ionic configuration. • For these complexes charge transfer does not take place. • The performance of the DFT functionals assayed was poor. - Abstract: The interaction energies (IE) between benzene and beryllium, magnesium and calcium were calculated at the CCSD(T)/CBS level and including corrections for core-valence and relativistic effects. The IE are 1.8, 2.3 and 3.2 kcal/mol for Be, Mg and Ca, respectively, In contrast with our previous findings for the benzene–Li complex, we found that the non-ionic structure is more stable than the ionic configuration. Thus, charge-transfer from alkaline earths to benzene would not take place. The performance of MP2 and DFT functionals is poor. At the complete basis set limit, M06-2X, M06-L, B97D and MP2 exhibited similar MAD (∼ 0.7–0.8 kcal/mol). When larger aromatic models were considered, the IE were similar to those computed for benzene. Finally, taking into account the drawbacks of the DFT functionals, the computed IE for the non-ionic adsorption of Be, Mg and Ca onto graphene, are tentatively estimated as 2.1, 2.7 and 2.9 kcal/mol, respectively

  4. The HFR Petten high dose irradiation programme of beryllium for blanket application

    International Nuclear Information System (INIS)

    This paper reports the objectives of a high dose irradiation of beryllium in the High Flux Reactor in Petten. In addition, the nuclear parameters, irradiation parameters and the provisional test-matrix, i.e. Beryllium grades and pebbles is presented. The irradiation will be performed in the frame of the European Programme for the development of the Helium Cooled Pebble Bed (HCPB) to study the irradiation behaviour of Beryllium. Part of the materials will be provided by Japanese and Russian partners, for which cooperation through IEA agreements is being put into place. (author)

  5. Loading beryllium targets to extend the high flux isotope reactor's cycle length

    International Nuclear Information System (INIS)

    Various arrangements of beryllium loadings to create an internal neutron reflector in the flux trap region of the Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) have been investigated. In particular, the impact upon fuel cycle length has been studied by performing calculations using the HFIR MCNP-based model HFV4.0. This study included examining perturbations in reactivity, flux, and power distribution caused by the various beryllium loadings. The HFIR Cycle 400 core configuration was used as a reference to calculate the impact of beryllium loadings upon cycle length. Three different configurations of beryllium loadings were investigated and compared against the Cycle 400 benchmark calculations; Cases 1 through 3 modeled combinations of 12 and 18 beryllium rods loaded into unused experimental sites. Calculated eigenvalues have shown that potential increases in reactivity between 0.56 and 0.79 dollars are attainable, depending on the various beryllium configurations. These results correspond to possible increases in fuel cycle length ranging between 2.3% and 3.3%. On the basis of their practicality, cost versus benefit, and greater potential for implementation, Cases 2 and 3 (both with 18 beryllium rods) were studied further and are herein reported in greater detail. Neutron flux distributions for Cases 2 and 3 were calculated at the horizontal mid-plane of the flux trap region, which showed no significant changes in the thermal flux magnitude and radial profile in comparison to Cycle 400. Likewise, safety analysis related parameters were contrasted, revealing power increments of up to 2% near the inside edge of the inner fuel element, well below the maximum acceptable value of 9%, a standing guideline employed for experiments at the HFIR. Additionally, the average neutron heat generation rate in beryllium rods and the maximum heat generation rate were evaluated to confirm that the design provides adequate coolant flow inside the rod and around the

  6. Conditions for preparation of ultrapure beryllium by electrolytic refining in molten alkali-metal chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Wohlfarth, Hagen

    1982-02-01

    Electrolytic refining is regarded as the most suitable process for the production of beryllium with impurity contents below 1 at.-ppM. Several parameters are important for electrolytic refining of beryllium in a BeCl/sub 2/-containing LiCl-KCl melt: current density, BeCl/sub 2/ content, electrolyte temperature, composition of the unpurified beryllium and impurity-ion concentrations in the melt, as well as apparatus characteristics such as rotation speed of the cathode and condition of the crucible material. These factors were studied and optimized such that extensive removal of the maximum number of accompanying and alloying elements was achieved.

  7. Study of beryllium redeposition under bombardment by high intensity -low energy- hydrogen ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Gureev, V.M.; Guseva, M.I.; Danelyan, L.S. [Russian Research Centre Kurchatov Inst., Moscow (Russian Federation)] [and others

    1998-01-01

    The results of studying the erosion of beryllium under an effect of intense ion fluxes with the energy of 250 eV, at the fluences {approx}10{sup 2}1 cm{sup -2}, at the MAGRAS-stand are given. The operating conditions under which a practically-complete redeposition of the sputtered beryllium upon the target surface were experimentally-realized. A change in the microstructure of a beryllium target under sputtering and redeposition is analyzed. Some technological applications are considered. (author)

  8. Feasibility of organo-beryllium target mandrels using organo-germanium PECVD as a surrogate

    International Nuclear Information System (INIS)

    Inertial Confinement Fusion capsules incorporating beryllium are becoming attractive for use in implosion experiments designed for modest energy gain. This paper explores the feasibility of chemical vapor deposition of organo-beryllium precursors to form coating materials of interest as ablators and fuel containers. Experiments were performed in a surrogate chemical system utilizing tetramethylgermane as the organometallic precursor. Coatings with up to 60 mole percent germanium were obtained. These coatings compare favorably with those previously reported in the literature and provide increasing confidence that a similar deposition process with an organo-beryllium precursor would be successful

  9. Failure prediction of thin beryllium sheets used in spacecraft structures

    Science.gov (United States)

    Roschke, Paul N.; Mascorro, Edward; Papados, Photios; Serna, Oscar R.

    1991-01-01

    The primary objective of this study is to develop a method for prediction of failure of thin beryllium sheets that undergo complex states of stress. Major components of the research include experimental evaluation of strength parameters for cross-rolled beryllium sheet, application of the Tsai-Wu failure criterion to plate bending problems, development of a high order failure criterion, application of the new criterion to a variety of structures, and incorporation of both failure criteria into a finite element code. A Tsai-Wu failure model for SR-200 sheet material is developed from available tensile data, experiments carried out by NASA on two circular plates, and compression and off-axis experiments performed in this study. The failure surface obtained from the resulting criterion forms an ellipsoid. By supplementing experimental data used in the the two-dimensional criterion and modifying previously suggested failure criteria, a multi-dimensional failure surface is proposed for thin beryllium structures. The new criterion for orthotropic material is represented by a failure surface in six-dimensional stress space. In order to determine coefficients of the governing equation, a number of uniaxial, biaxial, and triaxial experiments are required. Details of these experiments and a complementary ultrasonic investigation are described in detail. Finally, validity of the criterion and newly determined mechanical properties is established through experiments on structures composed of SR200 sheet material. These experiments include a plate-plug arrangement under a complex state of stress and a series of plates with an out-of-plane central point load. Both criteria have been incorporated into a general purpose finite element analysis code. Numerical simulation incrementally applied loads to a structural component that is being designed and checks each nodal point in the model for exceedance of a failure criterion. If stresses at all locations do not exceed the failure

  10. Analysis and characterization of heavy residues produced in {sup 129}Xe + {sup nat}Sn reactions between 8 and 25 AMeV; Analyse et caracterisation des residus lourds produits dans les reactions {sup 129}Xe + {sup nat}Sn entre 8 et 25 AMeV

    Energy Technology Data Exchange (ETDEWEB)

    Moisan, J

    2008-06-15

    Studies with the INDRA multidetector of the {sup 129}Xe + {sup nat}Sn reactions showed the unexpected existence of heavy fragments with a charge as large as Z=70. The charges of Xe and Sn are 54 and 50 respectively. Reactions between nuclei with a charge product greater than 2700 are dominated by deep inelastic collisions. For Xe + Sn the product is exactly 2700. After these observations, {sup 129}Xe + {sup nat}Sn reactions at 8, 12, 15, 20 and 25 AMeV have been done. It will then be possible to clarify if the heavy residues are formed by an incomplete fusion, massive transfers occurring in deep inelastic collisions or a very asymmetric fission of a compound system. This work will present experimental results obtained by the analysis of these experiments. We will show that heavy residues are formed with a production cross-section of 10{sup -2} mb. Angular distributions show that the residues can be produced by an incomplete fusion of the projectile and the target. The study of the products in coincidence with the residues shows that a compound system was formed, followed by a fission producing the residue and a lighter fragment. The comparison with a phenomenological model, HIPSE, confirms that the model is valid at these energies.

  11. Chemical interactions of beryllium with lithium-based oxides and stainless steel

    International Nuclear Information System (INIS)

    The chemical compatibility of Be with Li2SiO3, Li4SiO4 and stainless steel (AISI 316) was investigated in the temperature range between 600 and 900degC with maximum annealing times of 1000 h. Beryllium is of interest as a neutron multiplier material in a fusion reactor. First chemical interactions in the Be/Li2SiO3 and Be/Li4SiO4 systems occur at 650degC. The compatibility of Be with Li2SiO3 seems to be sufficient up to 650degC, whereas that with Li4SiO4 is sufficient even up to 700degC. At higher temperatures the silicide reaction products LixSiy become liquid which results in a strong local attack and penetration into the lithium silicates. Be interacts with stainless steel locally already at 600degC. The compatibility behavior in the Be/Li-silicate/stainless steel system under isothermal conditions is therefore determined by the Be/steel interactions. (orig.)

  12. Study of Kπ and Nπ systems in the K+n→KπN reaction at 8.25GeV/c

    International Nuclear Information System (INIS)

    The reaction K+n→KπN is studied at 8.25GeV/c from a 25000 picture exposure to the CERN 2m deuterium bubble chamber. The main results concern the channel K+n→K+π-p for which data at 4.6 and 12 GeV/c are also available. The K+π- system is dominated by K*(892) and K*(1420) which are studied separately. A partial wave analysis is performed for K+π- effective mass smaller than 1,6 GeV. This analysis shows an important S wave contribution which is smooth and broad and peaks around 1250 MeV. However a small narrower peak around 1350 MeV cannot be excluded. The pπ- system shows a wide bump at threshold. The properties of this bump are mainly diffractive. It is globally interpreted by a reggeised Deck model with π exchange but the data show that nucleon exchange must be considered for a complete interpretation of the phenomenon. An s-channel analysis is also discussed

  13. Study of nuclear reactions and analog isobar states in the system He8 + p for low energy with the help of MAYA active target

    International Nuclear Information System (INIS)

    With the resent improvements in the field of exotics beams, and specially with the SPIRAL facility at GANIL, we were able to study He9 shell inversion already known for Be11 and Li10, which are two members of the N=7 family. A new detector was developed and also the software tools for the data analysis. This detector is at the same time the target (active-target) and is called MAYA. The He9 was studied by determining the properties of its isobaric analogue states in Li9. The characteristics of the IAS (isomeric analog state) states were determined by an analysis of the resonances in the elastic scattering cross section for He8 + p from 2 up to 3.9 MeV/n. A study of (p,d) and (p,t) reactions was done too, in this domain of energy. By comparing the experimental results with calculations, an assignation of spin and parity for two states in He9 was possible. (author)

  14. Specification for nuclear-grade beryllium oxide powder

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This specification defines the physical and chemical requirements of nuclear-grade beryllium oxide (BeO) powder to be used in fabricating nuclear components. 1.2 This specification does not include requirements for health and safety. , , It recognizes the material as a Class B poison and suggests that producers and users become thoroughly familiar with and comply to applicable federal, state, and local regulations and handling guidelines. 1.3 Special tests and procedures are given in Annex A1 and Annex A2. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  15. Thermal Induced Processes in Laminar System of Stainless Steel - Beryllium

    International Nuclear Information System (INIS)

    The paper reports on investigation of the laminar system 'stainless steel 12Cr18Ni10Ti - Be' at thermal treatment. There have been determined sequences of phase transformations along with relative amount of iron-containing phases in the samples subjected to thermal beryllization. It has been revealed that thermal beryllization of stainless steel thin foils results in γ→α transformation and formation of the beryllides NiBe and FeBe2. It has also been revealed that direct γ→α- and reverse α→γ-transformations are accompanied by, correspondingly, formation and decomposition of the beryllide NiBe. It is shown that distribution of the formed phases within sample bulk is defined by local concentration of beryllium. Based on obtained experimental data there is proposed a physical model of phase transformations in stainless steel at thermal beryllization.

  16. Modelling of radiation impact on ITER Beryllium wall

    International Nuclear Information System (INIS)

    In the ITER H-Mode confinement regime, edge localized instabilities (ELMs) will perturb the discharge. Plasma lost after each ELM moves along magnetic field lines and impacts on divertor armour, causing plasma contamination by back propagating eroded carbon or tungsten. These impurities produce enhanced radiation flux distributed mainly over the beryllium main chamber wall. The simulation of the complicated processes involved are subject of the integrated tokamak code TOKES that is currently under development. This work describes the new TOKES model for radiation transport through confined plasma. Equations for level populations of the multi-fluid plasma species and the propagation of different kinds of radiation (resonance, recombination and bremsstrahlung photons) are implemented. First simulation results without account of resonance lines are presented.

  17. Preparation of nuclear purity beryllium oxalate tri-hydrate

    International Nuclear Information System (INIS)

    In this report we have gathered the whole of the knowledge acquired by our group during the campaign for preparation of beryllium oxalate we carried out through the first half year of 1962. The reader shall find in the first place information and bibliographic data gathered by Miss OLLIVIER, documentalist of the Section d'Etudes, Recherches et Applications Chimiques. We then describe the original process perfected in the laboratories, and the production techniques we employed for the semi-large operative units. Finally, we publish the results we obtained on one hand on the chemical aspect, in the industrial meaning of the term, which is to-day concerning the ponderal output, on the other hand on the analytical aspect as you can evidently not dissociate the quantity of substance produced from its purity. (authors)

  18. Stress distribution and fracture behavior of beryllium compact tension specimens

    International Nuclear Information System (INIS)

    Compact tension specimens of beryllium (Be) were designed to study fracture behavior and mechanical properties. The local stress distribution near a notch in a compact tension specimen was measured in situ by the combination of an X-ray stress analysis and a custom-designed load device. The fracture morphology was observed by scanning electron microscopy. The result showed that the local stresses near the notch tip are much higher than in other areas, and cracking occurs first in that area. The load-crack opening displacement curve of the Be compact tension specimen was obtained, and used to calculate the fracture toughness as 15.7 MPa√m. The compact tension specimen fracture surfaces were mainly characterized by cleavage fracture over three different areas. Cleavage micro-cracks along the basal slip plane were formed at the crack tip, and their growth was controlled by the primary stress after reaching a critical length

  19. Nuclear charge radius measurements of radioactive beryllium isotopes

    CERN Multimedia

    2002-01-01

    We propose to measure the nuclear charge radii of the beryllium isotopes $^{7,9,10}$Be and the one-neutron halo isotope $^{11}$Be using laser spectroscopy of trapped ions. Ions produced at ISOLDE and ionized with the laser ion source will be cooled and bunched in the radio-frequency buncher of the ISOLTRAP experiment and then transferred into a specially designed Paul trap. Here, they will be cooled to temperatures in the mK range employing sympathetic and direct laser cooling. Precision laser spectroscopy of the isotope shift on the cooled ensemble in combination with accurate atomic structure calculations will provide nuclear charge radii with a precision of better than 3%. This will be the first model-independent determination of a one-neutron halo nuclear charge radius.

  20. Electromagnetic properties of the Beryllium-11 nucleus in Halo EFT

    Directory of Open Access Journals (Sweden)

    Hammer H.-W.

    2010-04-01

    Full Text Available We compute electromagnetic properties of the Beryllium-11 nucleus using an effective field theory that exploits the separation of scales in this halo system. We fix the parameters of the EFT from measured data on levels and scattering lengths in the 10Be plus neutron system. We then obtain predictions for the B(E1 strength of the 1/2+ to 1/2− transition in the 11Be nucleus. We also compute the charge radius of the ground state of 11Be. Agreement with experiment within the expected accuracy of a leading-order computation in this EFT is obtained. We also indicate how higher-order corrections that affect both s-wave and p-wave 10 Be-neutron interactions will affect our results.