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301.
J. Nemeth M. Barranco C. Ngô E. Tomasi 《Zeitschrift für Physik A Hadrons and Nuclei》1985,320(4):691-692
We have used a self-consistent time dependent Thomas-Fermi model at finite temperature to calculate the dynamical evolution of hot and compressed nuclei. It has been found that nuclei can accomodate more thermal energy than compressional energy before they break. 相似文献
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Synthetic studies on Mansonone F and Biflorin are described. Synthesis of ketone 12 has been achieved by utilizing tetrahydronaphthalene 8 which in turn was prepared from the 5-methoxy-alpha-tetralone 3. The conversion of 8 into ketone 12 was accomplished in four steps (O-alkylation with ethyl bromoacetate, dehydrogenation, alkaline hydrolysis and cyclization with phosponate ester). 相似文献
305.
The excited state properties of linear, planar, and spherical hydrogenated silicon nanostructures are studied systematically with use of a time-dependent Hartree-Fock (TDHF) approach with a semiempirical Hamiltonian. The calculated optical gaps decrease significantly from linear, planar, to spherical silicon structures, showing that the optical gap is dimensionality dependent and hence it can be varied by solely managing the shape of the nanostructures. Remarkably, the calculated exciton sizes of the lowest dipole-allowed excited states for both silicon chains and planes are approximately 26 A, revealing that the quantum confinement effect should be significantly enhanced when the sizes of silicon nanostructures are smaller than this value but not dependent on the dimensionality. A similar trend is also observed for hydrogenated silicon spherical clusters. 相似文献
306.
[structure: see text]. A new series of amphiphilic G1-G3 dendrons containing purely aliphatic hydrocarbon dendritic surface sectors and one or two carboxylic acid group(s) at the focal point was synthesized in good yields. The key branching steps involve diallylation reactions of diethyl malonate or Meldrum's acid. These dendrons are highly soluble in hexane despite having highly polar carboxylic acid groups at the focal point. 相似文献
307.
Conventional methods for detecting single-nucleotide polymorphisms (SNPs), the most common form of genetic variation in human
beings, are mostly limited by their analysis time and throughputs. In contrast, advances in microfabrication technology have
led to the development of miniaturized platforms that can potentially provide rapid high-throughput analysis at small sample
volumes. This review highlights some of the recent developments in the miniaturization of SNP detection platforms, including
microarray-based, bead-based microfluidic and microelectrophoresis-based platforms. Particular attention is paid to their
ease of fabrication, analysis time, and level of throughput. 相似文献
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In this paper, we study the problem of when the corona algebra of a non-unital C*-algebra is purely infinite. A complete answer
is obtained for stabilisations of simple and unital algebras that have enough comparison of positive elements. Our result
relates the pure infiniteness condition (from its strongest to weakest forms) to the geometry of the tracial simplex of the
algebra, and to the behaviour of corona projections, despite the fact that there is no real rank zero condition. 相似文献