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81.
Following the method developed by the authors,recently,the equation of state of hot nuclei(238U in concrete) before break-up was investigated numerically.The isotherms are drawn in the plan of the general pressure P versus volume VRT. They are similar to those of Van der Waals gas.The critical temperature of phase transition should correspond to the isotherm with one turning point only.It turns out that the data of mass yield distribution can be reproduced by many pairs of parameters T and VRT (freeze-out temperature and freeze-out volume) varying in certain range.For each isotherm (each T),the data are always best reproduced by the value of VRT located at the maximum general pressure within two phases coexistence region. 相似文献
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A method to estimate the lattice energies E(latt) of nitrate salts is put forward. First, E(latt) is approximated by its electrostatic component E(elec). Then, E(elec) is correlated with Mulliken atomic charges calculated on the species that make up the crystal, using a simple equation involving two empirical parameters. The latter are fitted against point charge estimates of E(elec) computed on available X-ray structures of nitrate crystals. The correlation thus obtained yields lattice energies within 0.5 kJ/g from point charge values. A further assessment of the method against experimental data suggests that the main source of error arises from the point charge approximation. 相似文献
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Conclusions Tri(dimethylamino)phosphine and trimethyl phosphite react with the 2-p-dimethylaminoanil of 1,3-dimethyl-1,2,3-propanetrione to form a bipolar 11 adduct with a P-N bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 436–438, February, 1979.The authors wish to thank E. I. Gol'dfarb and R. G. Gainullina for recording the31P NMR and PMR spectra. 相似文献
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Trans-N,N-dialkyl-N,N-dibenzoyl-1,2-diamino-1-chloroethylenes — the first representatives of a new chemical class — and N,N-dialkyl-N,N-dibenzoyl-1,2-diaminoethylenes were obtained by benzoylation of N,N-dialkyl-1,4-diaza-1,3-butadienes. On increase in pressure to 10,000 atm, the yields of the N,N-dibenzoylated 1,2-diamino-1-chloroethylenes increase, and those of the N,N-dibenzoylated 1,2-diaminoethylenes decrease.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2038–2041, September, 1989. 相似文献
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