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1.
The efficiency with which a magnetic field acts on sublevels of the first and second doublets of a hydrogen-like atom is shown to vary because of relativistic effects by a factor of 1 ? 2γ(l + 1)/(2l + 3) and 1 ? 2γl/(2l ? 1), respectively, where γ is the ratio of the electron binding energy to the rest energy and l is the quantum number of the orbital angular momentum.  相似文献   
2.
Perfluoro-1-octene was used as a model for developing a method for the preparative ozonolysis of perfluoro-1-alkenes to the corresponding perfluoro-nor-alkenals. Perfluoroheptanal was synthesized.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1146–1147, June, 1994.  相似文献   
3.
The kinetics of CO oxidation on heterophase surfaces composed of two different types of patches M1 and M2 is analyzed. The kinetic conjugation of the patches caused by COads spillover leads to the substantial change in reaction rate temperature dependences, as well as to the appearance of a low-temperature, superadditive activity.  相似文献   
4.
Experiments on permanent lattice-defect formation induced by electronic excitation of rare-gas solids are presented. The creation of triplet excitons Γ(3/2) is found to be the primary process, followed by the exciton self-trapping. Probable models of defect formation are discussed. Fiz. Tverd. Tela (St. Petersburg) 40, 903–906 (May 1998) Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor.  相似文献   
5.
The feasibility of obtaining electrically conducting and active films by the electropolymerization of aniline in butylpyridinium tetrachloroaluminate or hexachlorodialuminate as the medium has been demonstrated. Identical voltamperometric characteristics with a potential peak of 0.5 V were found in these films and the compound formed upon the electrochemical polymerization of aniline in 20% hydrochloric acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 212–214, January, 1991.  相似文献   
6.
NMR spectroscopy and X-ray crystallography, the two primary experimental methods for protein structure determination at high resolution, have different advantages and disadvantages in terms of sample preparation and data collection and analysis. It is therefore of interest to assess their complementarity when applied to small proteins. Structural genomics/proteomics projects provide an ideal opportunity to make such comparisons as they generate data in a systematic manner for large enough numbers of proteins to allow firm conclusions to be drawn. Here we report a comparison for 263 unique proteins screened by both NMR spectroscopy and X-ray crystallography in our structural proteomics pipeline. Only 21 targets (8%) were deemed amenable to both methods based on an initial 2D 15N-HSQC NMR spectrum and optimized crystallization trials. However, the use of both methods in the pipeline increased the total number of targets amenable to structure determination to 107, with 43 amenable to NMR only and 43 amenable to X-ray crystallographic methods only. We did not observe a correlation between 15N-HSQC spectral quality and the success of the same protein in crystallization screens. Similar results were found for an independent set of 159 proteins as reported in the accompanying paper by Snyder et al. Thus, we conclude that both methods are highly complementary, and in order to increase the number of proteins suited for structure determination, we suggest that both methods be used in parallel in screening of all small proteins for structure determination.  相似文献   
7.
CO oxidation on the (111) face of Ni has been studied over a wide temperature range and reactant ratio in CO+O2 reaction mixtures. A significant nonstationary increase in the reaction rate due to the formation of a two-dimensional surface oxide has been found. Subsequent formation of threedimensional NiO(111) phase sharply decreases the CO oxidation rate.
CO (111) Ni (CO+O2). , . , NiO(111) CO.
  相似文献   
8.
Monoclinic crystals of ammonium hydrofluoride fluoro complexes of zirconium and hafnium (NH4)4M(Zr(Hf))3F17 · 2HF (M = Li, Na) are synthesized and studied. Their unit cell parameters are determined. IR spectra of the synthesized compounds are measured in the range of 350–4000 cm–1.  相似文献   
9.
Electric conductivity, photoconductivity, and electro-and magneto-optical properties of films from a novel polymeric complex of 4-methacryloyloxy-(4′-carboxy-3′-hydroxy)azobenzene with cobalt were studied. Electric conductivity and visible photoconductivity are determined by the orientation effects of azobenzene groups and by charge-carrier generation and transport in the polymer films. A change in the spatial orientation of the photoinduced dipole moments of azobenzene groups in an external electric or magnetic field is accounted for by the appearance of forces acting on charged magnetic metal ions that are rigidly bound to these fragments.  相似文献   
10.
The homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCO 2 spillover. Diagrams of steady states depending on the portion of surface patchm 1 at various temperatures and pressure ratiosP(O 2)/P(CO) have been constructed. The ratios of different type patches corresponding to the maximum overall reaction rate have been found.  相似文献   
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