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[en] In this study, the proton and neutron densities, charge densities, rms nuclear charge radii, rms nuclear mass radii, rms nuclear proton, neutron radii, and neutron skin thickness are calculated by using Hartree-Fock method with an effective nucleon-nucleon Skyrme interactions with SI, SIII, SIV, T3, SKM, and SKM* parameters. These nuclear properties for the neutron-rich isotopes of B (Boron) are presented. The calculated results are compared with the experimental and theoretical results of other researchers.
[en] The thermoelectric properties, that is the Seebeck coefficient, and electrical and thermal conductivity, of doped β-boron have been measured from 300 to 1600 K. Most of the useful doping elements are transition metals and occupy interstitial sites in the lattice. The highest figure of merit so far achieved at 1000 K is ZT = 0.11 for P-type, polycrystalline, hot-pressed β-boron doped with copper. Higher values may be achievable once a better P-type dopant is found. Some experiments on B68Y, α-B12Al, B4C, and B6Si are described. Transition metals appear to be effective dopants for B68Y and B4C
[en] The sintering powder is introduced in a graphite die whose walls are made of or completely covered, so as to form a seal, with a coating of hexagonal or amorphous boron nitride. A pressure of around 80 to 1000 bars is applied in the die and the temperature is gradually raised until it reaches a level of 1400 to 22000C which is maintained for 15 to 120 minutes at 100 to 1000 bars before cooling and removing the part from the mould
[fr]On introduit la poudre a fritter dans une matrice en graphite dont les parois sont faites ou recouvertes de facon totalement etanche d'un revetement de nitrure de bore hexagonal ou amorphe, on applique dans la matrice une pression de l'ordre de 80 a 1000 bars et on augmente progressivement la temperature jusqu'a un palier de 1400 a 22000C qu'on maintient pendant 15 a 120mn a 100 a 1000 bars avant de refroidir et demouler la piece
[en] Highlights: • Formation mechanisms of BO and BO2 radicals in the LIBS plasma were investigated. • Some of the BO and BO2 molecular emission bands were identified. • Boron Isotopes were detected by BO2 triatomic molecular emission bands by using LIBS method. In this research, at first we investigated the formation mechanisms of BO and BO2 radicals in the laser induced plasma of B4C sample. Several reactions between primitive fragments and the ambient atmosphere have been raised and discussed. Also the influence of four ambient atmospheres of air, nitrogen, oxygen and argon on molecular emission bands was investigated. Subsequently, in addition to investigating the BO molecular emission bands, we expanded molecular LIBS to triatomic molecules and for the first time we identified isotopes of boron from B2O3 sample, by BO2 triatomic molecular emission bands, and their isotopic shifts were calculated theoretically and coincide well the experiment at the results. The results indicated that isotopic shifts of the BO2 molecular emission bands related to the A → X system and for observed transitions are several hundred times larger than the boron atomic lines.
[en] A mass production technique for producing enriched boron was developed jointly by Kobe Steel and Stella Chemifa Co. in the 1990s. Enriched boron commercial production started in 2001 and since then, as a result of boron market research, several new enriched boron materials such as boron aluminum, boron acid, and boron carbide have been added to our production schedule. The demand for enriched boron is expected to increase rapidly if the material can be steadily supplied at a reasonable price. (author)