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961.
962.
Irina Brailovsky Peter Gordon Gregory Sivashinsky 《Combustion Theory and Modelling》2019,23(4):573-591
The paper is concerned with the experimentally known phenomenon that the detonation velocity of a tubular charge may markedly exceed that of a homogeneous charge of the same explosive. It is shown that the effect may be successfully reproduced using a simple quasi-one-dimensional two-layer model assuming the gas–solid system to be isothermal and the volumetric fraction of the solid phase to be small. In view of a considerable drop of the burned gas pressure/density, compared to the Chapman–Jouguet case, fast detonation may be perceived as a variety of weak (undercompressed) detonation. 相似文献
963.
Mikeska Emily R. Powell Cynthia B. Powell Gregory L. 《Journal of chemical crystallography》2021,51(4):457-464
Journal of Chemical Crystallography - Four osmium carbonyl complexes were synthesized via microwave heating by reacting either Os3(CO)12 or Os3(CO)10( $$\mu$$ -dppm) with dppe, where... 相似文献
964.
965.
Jinghui Wang Danny X. Liu Marcello Canova R. Gregory Downing Lei R. Cao Anne C. Co 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(1):277-284
Measuring the distribution of lithium in high capacity lithium-ion battery (LIB) electrodes is essential to understanding the coulombic losses during the lithiation/delithiation processes that occur while charging and discharging the cell. In this research, two half-cell prototypes were fabricated by electrochemically lithiating Sn foil anodes in 1M LiBF4 in a 1:1 (wt:wt) ethylene carbonate and dimethyl carbonate solutions at a constant potential of 0.50 and 0.67 V (vs. Li/Li+). The neutron depth profiling (NDP) technique was employed to study the Li distributions in the anodes. Li concentration profiles were resolved for the samples lithiated under different conditions for LIB studies. In addition, this paper demonstrated an in situ NDP measurement of an electrochemical cell with a thin window design, which reveals the dynamics of lithium distribution within the Sn anode. 相似文献
966.
We give an effective proof of a theorem of Dani and Margulis regarding values of indefinite ternary quadratic forms at primitive integer vectors. The proof uses an effective density-type result for orbits of the groups SO(2, 1) on SL(3, ?)/SL(3, ?). 相似文献
967.
968.
Sherif M.S. Ibrahim Koushik Banerjee Kara A. Slater Gregory K. Friestad 《Tetrahedron letters》2017,58(52):4864-4866
Tamao–Fleming oxidation of the N-dimethylphenylsilylmethyl group linked to the nitrogen of a peptide bond enables access to dipeptide N,O-acetal functionality. The N-silylmethyl functionality serves as a latent form of the N,O-acetal which is revealed after peptide bond construction. 相似文献
969.
David A. Gregory Norman J Pullman Stephen J. Kirkland 《Linear and Multilinear Algebra》2013,61(1-2):131-144
We investigate the subspace of the space of all n × n Boolean (0,1)-matrices, spanned by the powers of an arbitrary matrix. We estimate the maximum dimension of such spaces as a function of n and show that their bases consists of consecutive integer powers of the matrix, starting at I. We also determine the maximum dimension of the space spanned by the powers of as symmetric matrix and characterise the matrices achieving that maximum. 相似文献
970.