Energy and blast performance of beryllium in a model thermobaric composition in comparison with aluminum and magnesium

A direct comparison is made between the effectiveness of Al,Mg,and Be powders as additional fuels in model thermobaric compositions containing 20%fuel,20%ammonium perchlorate,and 60%RDX(1,3,5-Trinitro-1,3,5-triazacyclohexane)passivated with wax.Experimentally determined calorimetric measurements of the heat of detonation,along with the overpressure histories in an explosion chamber filled with nitrogen,were used to determine the quasi-static pressure(QSP)under anaerobic conditions.Overpressure measurements were also performed in a semi-closed bunker,and all blast wave parameters generated after the detonation of 500 g charges of the tested explosives were determined.Detonation calorimetry results,QSP values,and blast wave parameters(pressure amplitude,specific and total impulses)clearly indicate that Be is much more effective as an additional fuel than either Al or Mg in both anaerobic post-detonation reactions as well as the subsequent aerobic combustion.The heat of detonation of the RDXwax/AP/Be explosive mixture is over 40%and 50%higher than that of the mixture containing aluminum and magnesium instead of beryllium,respectively.Moreover,the TNT equivalent of the Be-containing composition due to the overpressure in the nitrogen-filled explosion chamber is 1.66,while the equivalent calculated using an air shock wave-specific impulse at a distance of 2.5 m is equal to 1.69.The high values of these parameters confirm the high reactivity of beryllium in both the anaerobic and aerobic stages of the thermobaric explosion.

Petrogenesis of Oligocene Granitoids and its Implications on Beryllium Mineralization at Pagele,Nianqingtanggula Mountain(Central Tibet)

The newly discovered Oligocene granitoids(33.1-28.7 Ma)at Pagele are magmatic rocks related to beryllium mineralization during the India-Asia late-collisional stage.This discovery provides an ideal example to study the latecollisional orogeny and beryllium prospecting in the Lhasa terrane.The Oligocene granitoids include porphyritic granodiorite,StageⅠ,ⅡandⅢgranites,and granitic pegmatite.Geochemical analysis shows that the porphyritic granodiorite is characterized by high SiO_(2),K_(2)O,totalΣREE contents,and(La/Yb)N ratios;while the latter two by higher SiO_(2),lowerΣREE and(La/Yb)N ratios.Notably,the granitic pegmatite has extremely high Y/Ho,low K/Rb and Zr/Hf,and distinct REE tetrad effect(1.14-1.21).This study suggests that the porphyritic granodiorite may be derived from partial melting of beryllium-rich materials composed of Lhasa ancient crust(70%-80%)and enriched Lhasa lithospheric mantle(20%-30%)under the tearing subduction of Indian slab.The three-stage granites and granitic pegmatite,which contain higher beryllium contents or beryls,were likely generated by highly fractionation of the porphyritic granodioritic magma or other homologous magma.Considering the possible genetic and spatial link between Indian slab tear and rifts,we suggest that highly-fractionated granites in rifting systems represent important Be prospecting targets in the Lhasa terrane.

Microstructure evolution of copper doped beryllium thin films

Copper （Cu） doped beryllium （Be） thin films were deposited on silicon substrates by using a simple ion beam sputtering method, which can also realize the varying of Cu doping concentration. Detailed morphological and structural characterizations of the samples clearly disclose a microstructure evolution of films upon doping Cu. Doping Cu can effectively suppress film grain growth, causing a small grain size as well as uniform size distribution. Furthermore, doping Cu affects the crystallographic texture of film, which leads to the formation of more compact film structure. In particular, the surface smoothness of the doped films is significantly improved, which makes them promising candidates for various applications.

Energies and Transition Rates of Low-Lying Excited States for Beryllium

Low lying excited states of beryllium are calculated with multiconfiguration interaction method. The relativisitic corrections and mass polarization are included. The oscillator strength and radiation rates are also calculated. Our results are in good agreement with other theoretical data.

Theoretical Study on Dissociation Mechanisms of Di-ethyl Berylliums and Di-t-butyl Berylliums

The potential energy surfaces （PES） of unimolecular dissociation reactions for di-ethyl beryl- lium and di-t-butyl beryllium are investigated by B3LYP, CCSD（T）, and G3B3 approaches. Possible reaction pathways through either the radical or transition state （TS） of the molecules are considered. The geometries, vibrational frequencies and relative energies for various sta- tionary points are determined. From the study of energetics, the TS pathways arising from concerted molecular eliminations are indicated to be the main dissociation pathways for both molecules. The PES differences of the dissociation reactions are investigated. The activation energies and rate constants will be helpful for investigating the predictive ability of the reaction in further theoretical and experimental research.

Synthesis and ceramization of polycarbosilane containing beryllium

Polycarbosilane containing beryllium(BPCS) precursors was prepared by the reaction of polycarbosilane(PCS) with beryllium acetylacetone(Be(acac)2).The analysis of structures and components of BPCS demonstrates that their main structures are basically the same as PCS.Ceramization of BPCS precursors shows that BPCS precursors are organic below 600 °C and inorganic at 800 °C.At 1400 °C,BPCS precursors convert into silicon carbide ceramics.The ceramization of different beryllium content precursors were studied,which show that beryllium plays an important role in the inhibition of crystalline grain growth of β-SiC at high temperature and it can adjust the dielectric constant of silicon carbide ceramics.

Current Status of the Fabrication of Li_4SiO_4and Beryllium Pebbles for CN HCCB TBM in SWIP

Tritium breeder and neutron multiplier as functional materials play an important role not only in ITER test blanket module （TBM） but also in fusion reactor. The paper describes the status of the fabrication of the two materials in Southwestern Institute of Physics （SWIP）. Li4SiO4 pebbles were fabricated by melt-spraying method. Most of the pebbles with the diazneter of 1.0 mm are well spherically shaped. The properties of the pebbles have been investigated. The results show that the pebbles produced by this method have a high density of 93% TD （theoretical density）. It was also found that the open/closed porosity will be decreased after thermal treatment, but the average crush load will be increased to 7 N. The rotating electrode process （REP） has been adopted to produce beryllium pebble for impurity control and mass production. The pebbles with the diameter of 1.0 mm were produced by REP. The beryllium pebbles produced by REP look almost perfectly spherical with a very smooth surface and a high density of 98% TD. The test results indicate that REP method has excellent prospects for the fabrication of beryllium pebbles and the attractiveness of their properties.

Influence of grain size on mechanical properties of isostatically pressed beryllium materials

Six kinds of beryllium powders with different particle sizes (4～15 μm) and low oxygen prepared by impact grinding were compacted and consolidated by cold hot isostatic pressing (CIP HIP). The tensile strength, yield strength, elongation and micro yield strength(MYS) of the materials were tested and it showed that the strength of the materials, especially the yield strength and micro yield strength(MYS) increase obviously with the refinement of grain size. From the XRD and TEM, the second phase is BeO which is finely dispersed in matrix. This is considered to be the main strengthening mechanism for CIP HIPed beryllium materials with higher purity.

Color Enhancement by Diffusion of Beryllium in Dark Blue Sapphire

Diffusion of beryllium was performed on dark blue sapphire from China and Australia.The samples were heated with beryllium as a dopant in a furnace at 1 600℃ for 42 hin air.After beryllium diffusion,samples were analyzed by UV-Vis,FTIR,and WD-XRF spectroscopy.After heat-treatment with Be as a catalyst,the irons of the ferrous state were changed to the ferric state.Therefore,reaction of Fe^(2+)/Ti^(4+) IVCT was decreased.The absorption peaks at 3 309cm^(-1) attributed to OH radical were disappeared completely due to carry out heat treatment.Consequently,the intensity of absorption band was decreased in the visible region.Especially,decreased absorption band in the vicinity of 570 nm was responsible for the lighter blue color.Therefore,we confirmed that the dark blue sapphires from China and Australia were changed to vivid blue.

Wavefunction and energy of the 1s^2 2sns configuration in a beryllium atom

A new set of trial functions for 1s^22sns configurations in a beryllium atom is suggested. A Mathematica program based on the variational method is developed to calculate the wavefunctions and energies of 1s^22sns （n = 3 - 6） configurations in a beryllium atom. Non-relativistic energy, polarization correction and relativistic correction which include mass correction, one- and two-body Darwin corrections, spin-spin contact interaction and orbit-orbit interaction, are calculated respectively. The results are in good agreement with experimental data.

Ore-Forming Mechanism of the Asikaerte Granitic Pegmagtite Beryllium Deposit in Xinjiang, China

Objective Granitic pegmatite has great significance for studying magmatic-hydrothermal evolution, which is the main formation mechanism of rare metal deposits. Conventionally, granitic pegmatite rare metal deposits are regarded as crystallization from H20-saturated granite magma that formed in the late fractional crystallization of granitic magma. However, some scholars recently believed that the liquid immiscibility of granitic magma promoted the formation of pegmatite deposits. The Asikaerte beryllium deposit in Xinjiang, China, bearing metallogenic belts from lower granite belt to upper pegmatite belt, could benefit us to understand the formation of pegmatite through analyzing fluid and melt inclusions data.

Analysis of beryllium poisoning effect on liquid metal reactor with U–Be alloy fuel

A liquid metal reactor(LMR) loaded with a fuel compound of uranium and beryllium(U-Be alloy fuel),which was cooled by a lead-bismuth eutectic alloy(PbBi),has been applied in Russian Alfa-class nuclear submarines.Because of the large amount of beryllium in the core, the reaction between the beryllium atoms and neutrons could result in the accumulation of 3 He and 6 Li, which are called the "poisoned elements" owing to their large thermal neutron capture cross section. The accumulation of neutron absorber can affect the performance of a reactor. In this study, the Super Multi-functional Calculation Program(SuperMC) code, which was developed by Institute of Nuclear Energy Safety Technology of the Chinese Academy of Sciences(INEST, CAS), was adopted to illustrate the influence of beryllium on an LMR.

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

The concentration, modes of occurrence and geological origin of beryllium in five workable coal beds from the Pu＇an Coalfield of Guizhou 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.

Beryllium Surface Modified by B Ion Implantation

Beryllium is implanted with 100 keV, 2×10^(17) B/cm^2 and post-implanted sample is annealed at 650℃ for 1 h.Hardness measurement indicates that the hardness increases with implantation and can further be modified by post-implantation heat treatment. Profile measurement shows that implantation causes contamination on the surface of beryllium. During annealing boron diffuses out of beryllium and carbon on surface diffuses into beryllium. Beryllium surface is modified by composition change and carbide formation.

Beryllium carbide as diffusion barrier against Cu:First-principles study

Beryllium carbide is used in inertial confinement fusion(ICF)capsule ablation material due to its low atomic number,low opacity,and high melting point properties.We used the method of climbing image nudged elastic band(CINEB)to calculate the diffusion barrier of copper atom in the crystal of beryllium and beryllium carbide.The diffusion barrier of copper atom in crystal beryllium is only 0.79 eV,and the barrier in beryllium carbide is larger than 2.85 eV.The three structures of beryllium carbide:anti-fluorite Be2C,Be2C-Ⅰ,and Be2C-Ⅲhave a good blocking effect to the diffusion of copper atom.Among them,the Be2C-Ⅲstructure has the highest diffusion barrier of 6.09 eV.Our research can provide useful help for studying Cu diffusion barrier materials.

Isotope Shift Calculations of Stable and Short-Lived Beryllium Isotopes

The isotope shifts of the 282 1S0 to 2s2p 1P1 and 3P1 transitions in the four-electron beryllium atom are calcu- lated by using the multi-configuration Dirac-Hartrce-Fock method and the relativistic configuration interaction approach for the stable and short-Bved beryllium isotopes. The results provided herein can be employed for the consistency check with the nuclear rms charge radii from the experimental isotope shifts by using the correspond- ing transitions for the short-lived nuclei 7,10-12Be and 14 Be. The analogous isotope shift results could also be obtained for the beryllium-like ions by the methods used here.

Calculating Binding Energy for Odd Isotopes of Beryllium （7 ≤ A ≤ 13）

In this article, we present exact solution of the Schr6dinger equation （for an N-identical body-force） for odd-A isotopes of Beryllium in the presence of Yukawa potential by Nikiforov-Uvarov （NU） method. The NU method can be used to solve second order differential equation. By this method, we find the wave equation and binding energy. Numerical results of binding energy are presented and show that these results are in good agreement with experimental values.

Ionization energies of beryllium in strong magnetic fields

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 × 10^5T. Systematic improvement over the Hartree-Fock results for the beryllium low-lying states has been accomplished.

Separation and determination of trace amounts of beryllium（Ⅱ）,alumini

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