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81.
82.
Metal-mediated allylations of difluoroacetyltriakylsilanes with various allyl bromides in aqueous media form homoallylic alcohols exclusively. The common Brook rearrangement, carbon to oxygen-silyl migration, is totally suppressed with no detectable formation of silyl enol ether. Influence of solvents on reaction is studied. Reactivity differences between indium and zinc are also described. 相似文献
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86.
M. J. Welch 《Journal of Radioanalytical and Nuclear Chemistry》1993,171(1):269-276
The field Nuclear Medicine has expanded rapidly over the last two decades. Individuals with training in radiochemistry are needed in industry, medical centers and hospitals. Although basic training in organic chemistry, inorganic chemistry, biochemistry or pharmacy are required, radiochemistry knowledge is essential for all of these individuals. Opportunities and training requirements in these areas will be discussed. 相似文献
87.
The self-consistent average-phonon (SCAP) treatment, developed in earlier papers for monoatomic solids was extended to the alkali halides for which self-consistent calculations were not available. The quantitative comparison of SCAP with an average quaiharmonic (AQH) treatment for Ar and for NaCl showed that AQH highly overestimated the thermal pressure. Because of this overestimation, we conclude that the lattice instability reported by Boyer for NaCl, which he considered to be related to melting, is a consequence of using a quasiharmonic approximation. 相似文献
88.
H. Deden F.J. Hasert W. Krenz D. Lanske J. Morfin M. Pohl K. Schultze L. Welch G. Bertrand-Coremans H. Mulkens J. Sacton W. Van Doninck H. Burmeister I. Danilchenko D. Haidt P. Jobin C. Matteuzzi P. Musset A.J. Segar 《Physics letters. [Part B]》1977,67(4):474-478
New results are presented of an analysis of pictures taken during an exposure of Gargamelle to the CERN ν beam in 1975. In addition to three νμ+N→μ?+e++V0+ hadrons events previously reported, an excess is found of events of the type νμ+N→μ?+e++ hadrons without V0. An analysis of strange particle production in charged current events suggests a possible violation of the ΔS=ΔQ rule. Interpreted in terms of charm production, the data permit an estimate of branching ratios and production rate of charmed particles. A limit is also placed on charmed particle production by neutral currents. 相似文献
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90.
The molecular dynamics method of computer simulation was used to study the pressure and energy as a function of volume and temperature for f.c.c. neon with 6–12 Lennard-Jones interatomic forces and for b.c.c. iron with Morse interatomic forces. A self-consistent cell model was used to derive analytical formulae which describe the results of the computer experiments. A method for correcting the inherently classical results of the molecular dynamics calculations for the effect of quantum statistics is proposed. The results of the calculations are compared with experimental data and with various approximate methods for calculating the Grüneisen constant. 相似文献