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排序方式: 共有189条查询结果,搜索用时 31 毫秒
51.
N. Makhiyanov D. Kh. Safin R. R. Sharifullin A. S. Biktimerova 《Russian Journal of Applied Chemistry》2012,85(12):1879-1886
13C NMR spectroscopy was used to make a comparative characterization of the distribution of polyoxypropylene polyols synthesized on basic (KOH) and dimetal cyanide catalysts over the type of functionality, regioregularity, and stereotacticity. 相似文献
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Condensation in axisymmetric turbulent air-steam jets is studied theoretically and experimentally under bench experiment conditions in which a hot mist jet is injected from a nozzle into air. On the basis of the physico-mathematical model developed, four problems are considered: homogeneous condensation in the jet at a fairly low ambient air temperature, heterogeneous condensation on particles introduced into the jet at the nozzle outlet, heterogeneous condensation on particles ejected into the jet from the surrounding space, and condensation on ions entering the jet from a corona point on the flow axis. The local characteristics of the dispersed phase (mean particle size, standard deviation of the particle size, particle number and volume concentrations) and its integral characteristics (coefficient of vapor conversion into condensed phase and the optical thickness of the jet in different sections) are determined. The calculation results are compared with experimental data. As an application of the model developed, the characteristics of heterogeneous condensation in the jets of certain modern aircraft engines (IL-96-300, Tu-204, MiG-29, Boeing-707) are found on the assumption that the condensation occurs on particles entering the jet at the nozzle outlet and the particle growth rate in all stages (including the initial stage of particle irrigation) coincides with the growth rate of liquid drops. 相似文献
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NQR spectra are reported for 26 chlorosilanes; the mean frequency is a linear function of the sum of the Induction constants, of the substituents and can be used to deduce the polarity of the Si-Cl bond. Some of the compounds show marked broadening of the NQR lines at 77K, which is due to structural disorder in the solid. 相似文献
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Felix D. Sokolov Damir A. Safin Michael Bolte Elmira R. Shakirova Maria G. Babashkina 《Polyhedron》2008,27(14):3141-3145
A new bifunctional N-thiophosphorylated thiourea and 2,5-dithiobiurea of the common formula R[C(S)NHP(S)(OiPr)2]2 [R = –N(Ph)CH2CH2N(Ph)– (H2La); –NHNH– (H2Lb)] have been synthesized and characterized by IR, 1H, 31P spectroscopy and the single crystal X-ray diffraction method. The structure of the latter compound in CDCl3 and acetone-d6 solutions has been discussed in comparison with the monofunctional thiosemicarbazide PhNHNHC(S)NHP(S)(OiPr)2 (HLc). 相似文献