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排序方式: 共有151条查询结果,搜索用时 31 毫秒
31.
Grigorii A. Tikhomirov Konstantin O. Znamenkov Igor V. Morozov Erhard Kemnitz Sergei I. Troyanov 《无机化学与普通化学杂志》2002,628(1):269-273
Crystalline NO[Mn(NO3)3] ( I ) and (NO)2[Co(NO3)4] ( II ) were synthesized by reaction of the corresponding metal and a liquid N2O4/ethylacetate mixture. I is orthorhombic, Pca21, a = 9.414(2), b = 15.929(3), c = 10.180(2) Å, Z = 4, R1 = 0.0286. II is monoclinic, C2/c, a = 14.463(3), b = 19.154(4), c = 13.724(3) Å, β = 120.90(3), Z = 12, R1 = 0.0890. Structure I consists of [Mn(NO3)3]– sheets with NO+ cations between them. Two types of Mn atoms have CNMn = 7 and 8. Structure II is ionic containing isolated [Co(NO3)4]‐anions and NO+ cations with CNCo = 8. Crystals of Mn(NO3)2 ( III ) and Co(NO3)2 ( IV ) were obtained by concentration of metal nitrate hydrate solutions in 100% HNO3 in a desiccator with P2O5. III is cubic, Pa 3, a = 7.527(2) Å, Z = 4, R1 = 0.0987. IV is trigonal, R 3, a = 10.500(2), c = 12.837(3) Å, Z = 12, R1 = 0.0354. The three dimensional structure III is isotypic to the strontium and barium dinitrates. Structure IV contains a three dimensional network of interconnected Co(NO3)6/3 units with a distorted octahedral coordination environment of Co atoms. General correlations between central atom coordination and coordination modes of NO3 groups are discussed. 相似文献
32.
Boris A. Trofimov Elena Yu. Schmidt Igor A. Ushakov Elena Yu. Senotrusova Grigorii G. Aleksandrov 《Tetrahedron letters》2009,50(26):3314-3775
A new three-component reaction between alkyl aryl(hetaryl)ketoximes, acetylene, and aliphatic ketones in the superbasic systems KOH/DMSO and LiOH/CsF/DMSO (70-90 °C, initial acetylene pressure 13-15 atm, 5-60 min) affords novel 4-methylene-3-oxa-1-azabicyclo[3.1.0]hexanes in yields of up to 75%. Using KOH/DMSO, the side products of the reaction are O-vinylketoximes and 2-aryl(hetaryl)pyrroles, while with LiOH/CsF/DMSO, the reaction proves to be selective, only minor amounts of the corresponding alkyl aryl(hetaryl) ketones being detectable. 相似文献
33.
On the assumption that condensed matter at high pressures and temperatures behaves as an ideal gas, a functional dependence
of the adiabatic exponent on the Grüneisen constant was obtained, as well as an equation of state that relates the velocity
of the shock front and the mass velocity in the shock wave. The calculated estimates of the rate of unloading for cadmium,
tin, aluminum, and iron are given as functions of the mass velocities. A comparison with experimental data shows that such
an equation of state sufficiently well describes the behavior of the substance and can be used instead of the conventional
semiempirical dependences. 相似文献
34.
Yu. V. Kokhanenko 《International Applied Mechanics》2000,36(8):1067-1076
The concept of basic schemes is employed to construct discrete problems that approximate the basic three-dimensional problems of the elastic theory of composites in circular cylindrical coordinates for domains of arbitrary connectivity and complex geometry 相似文献
35.
Christian Werner Grigorii Kokhanenko Gennadii Matvienko Vitalii Shamanaev Yurii Grachjov Igor Znamenskii Ulrich G. Oppel 《Optical Review》1995,2(3):221-224
First, in this report an overview is given on the use of the Russian laser altimeter in space “LORA” as a lidar for cloud measurements. Secondly, the influence of multiple scattering is verified by analysis of the backscatter signals from clouds having the excellent range resolution of a rangefinder.Presented at the 7th International Workshop on Multiple Scattering Lidar/Light Experiments (MUSCLE7), July 21–23 1994, Chiba, Japan. 相似文献
36.
37.
Rubtsov IV Susumu K Rubtsov GI Therien MJ 《Journal of the American Chemical Society》2003,125(9):2687-2696
The excited-state dynamics of two conjugated bis[(porphinato)zinc(II)] (bis[PZn]) species, bis[(5,5'-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]ethyne (DD) and [(5,-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]-[(5',-15'-ethynyl-10',20'-bis(heptafluoropropyl)porphinato)zinc(II)]ethyne (DA), were studied by pump-probe transient absorption spectroscopy and hole burning techniques. Both of these meso-to-meso ethyne-bridged bis[PZn] compounds display intense near-infrared (NIR) transient S(1)-->S(n) absorptions and fast relaxation of their initially prepared, electronically excited Q states. Solvational and conformational relaxation play key roles in both DD and DA ground- and excited-state dynamics; in addition to these processes that drive spectral diffusion, electronically excited DA manifests a 3-fold diminution of S(1)-->S(0) oscillator strength on a 2-20 ps time scale. Both DD and DA display ground-state and time-dependent excited-state conformational heterogeneity; hole burning experiments show that this conformational heterogeneity is reflected largely by the extent of porphyrin-porphyrin conjugation, which varies as a function of the pigment-pigment dihedral angle distribution. While spectral diffusion can be seen for both compounds, rotational dynamics driving configurational averaging (tau approximately 30 ps), along with a small solvational contribution, account for essentially all of the spectral changes observed for electronically excited DD. For DA, supplementary relaxation processes play key roles in the excited-state dynamics. Two fast solvational components (0.27 and 1.7 ps) increase the DA excited-state dipole moment and reduce concomitantly the corresponding S(1)-->S(0) transition oscillator strength; these data show that these effects derive from a time-dependent change of the degree of DA S(1)-state polarization, which is stimulated by solvation and enhanced excited-state inner-sphere structural relaxation. 相似文献
38.
We consider a general minimal time problem with a convex constant dynamics and a lower semicontinuous extended real-valued target function defined on a Banach space. If the target function is the indicator function of a closed set, this problem is a minimal time problem for a target set, studied previously in particular by Colombo, Goncharov and Mordukhovich. We investigate several properties of the Fréchet and proximal subdifferentials for the infimum time function. Also explicit expressions of the above mentioned subdifferentials as well as various directional derivatives are obtained. We provide some examples to show the essentiality of assumptions of our theorems. 相似文献
39.
40.
Voitsekhovskii A. V. Nesmelov S. N. Dzyadukh S. M. Kopylova T. N. Degtyarenko K. M. Kokhanenko A. P. 《Russian Physics Journal》2019,62(2):306-313
Russian Physics Journal - The current-voltage characteristics and admittance of multilayer structures for organic LEDs based on the PEDOT:PSS/NPD/YAK-203/BCP system have been experimentally... 相似文献