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91.
92.
S. V. Burov S. V. Nikolaev M. P. Smironova G. E. Lupanova Yu. F. Bobrov A. M. Nevolin-Lopatin É. M. Kitaev 《Chemistry of Natural Compounds》1982,18(6):732-737
Two new analogs of the releasing factor of the luteinizing hormone with shortened amino acid sequences have been synthesized by the methods of classical peptide chemistry. The influence of the preparations on the action of chorionic gonadotropin and on the course of processes of ovulation in experimental animals has been studied. The promising nature in this direction of the search for active analogs for luliberin has been shown. 相似文献
93.
94.
V. K. Kryzhanovskii M. S. Trizno Z. G. Boiko A. F. Nikolaev 《Mechanics of Composite Materials》1969,5(6):991-993
It has been established that changing the elasticity of rigid crosslinked epoxy-novolac block copolymers changes the friction mechanism and wear characteristics. The optimal conditions for obtaining block copolymers with the greatest wear resistance have been determined. The results of testing epoxy novolacs in neutral and alkaline media are presented.Leningrad Lensovet Technological Institute. Translated from Mekhanika Polimerov, No. 6, pp. 1107–1109, November–December, 1969. 相似文献
95.
Based on an approach to non-Abelian propagation of color dipoles in a nuclear medium, we formulate a nonlinear k⊥ factorization for the breakup of photons and pions into forward hard dijets in terms of the collective Weizsäcker-Williams glue of nuclei. We find quite distinct practical consequences of nonlinear nuclear k⊥ factorization for interactions of pointlike photons and nonpointlike pions. In the former case, the large transverse momentum p⊥ of jets comes from the intrinsic momentum of quarks and antiquarks in the photon, and nuclear effects manifest themselves as an azimuthal decorrelation with an acoplanarity momentum of the order of the nuclear saturation momentum Q A . In the breakup of pions off free nucleons to the leading order in pQCD, the spectator parton has a small transverse momentum and the hard dijet cross section is suppressed. In the breakup of pions off heavy nuclei, the forward hard jets are predicted to be entirely decorrelated. We comment on the sensitivity of the pionic dijet cross section to the pion distribution amplitude. The predicted distinction between the breakup of photons and pions can be tested by the sphericity and thrust analysis of the forward hadronic system in the COMPASS experiment at CERN. 相似文献
96.
We investigate the valence electronic charge density of the C(60) (-) monomers in (C(60) (-))(n) polymer chains in K- and RbC(60) by means of a nonorthogonal tight-binding formalism using experimental data on the positions of the carbon atoms. Various configurations of the C(60) cages are considered. Starting from the ideal icosahedral C(60) structure and moving to the realistic, experimentally determined spatial configuration of the C(60) cages in K- and RbC(60), we observe a systematic increase of the electric quadrupole moments on the C(60) (-) monomers. We also confirm the validity of factorizing the charge density of a C(60) (-) monomer into an angular and a radial part. 相似文献
97.
V. F. Shkar’ E. I. Nikolaev V. N. Sayapin V. D. Poimanov 《Physics of the Solid State》2004,46(6):1073-1080
The field dependence of the high-frequency susceptibility and the ferromagnetic resonance were experimentally studied in a thin (d≈0.1 µm) (111)-oriented single-crystal film of substituted yttrium-iron garnet with the factor q?1. It was shown that the anomaly in the high-frequency susceptibility observed in a magnetic field H parallel to the normal to the film surface in the magnetization saturation region (H≈Hs) has a dual nature; more specifically, this anomaly is associated with an abrupt collapse of the stripe domain structure and a ferromagnetic resonance in the experimental configuration H ∥ [111] and h ⊥ H. In this case, the film transition from the inhomogeneous multidomain state to the homogeneous (single-domain) state at the point H≈Hs has no indications of a second-order phase transition. The experimental frequency-field dependence of ferromagnetic resonance (FMR) in the sample under study, having a characteristic minimum at the point ω0=5 MHz and HFMR=Hs, agrees qualitatively and quantitatively with calculations. The influence of the cubic magnetic anisotropy and the film thickness on the FMR spectrum and the orientation of the spontaneous magnetization in domains with respect to the film plane in the zero field H was theoretically studied. 相似文献
98.
A. V. Chistyakov P. A. Zharova M. A. Gubanov S. A. Nikolaev T. B. Egorova A. E. Gekhman M. V. Tsodikov 《Kinetics and Catalysis》2017,58(6):741-748
The results of a study on the activity and operational stability of an Au–Pd/MFI/Al2O3 catalyst in the reaction of ethanol conversion into a gasoline fraction of hydrocarbons are reported. In the presence of the Au–Pd/MFI/Al2O3 catalyst, ethanol was almost completely converted into an alkane–aromatic fraction of C3–C11 hydrocarbons at 300°C in an atmosphere of Ar; the yield of this fraction was as high as 90% on a feed carbon basis. It was established that, in the presence of the bimetallic Au–Pd catalyst, the yield of the target fraction increased by 10%, as compared with that on a monometallic Au-containing sample. The Au–Pd/MFI/Al2O3 catalyst exhibited much higher stability in a long-term experiment in comparison with the previously tested pilot sample of Pd–Zn/MFI/Al2O3. After a 40-h operation, the yield of the target fraction of C3+ hydrocarbons in the presence of the Au–Pd/MFI/Al2O3 catalyst decreased by 15%. The treatment of the catalyst with hydrogen led to the complete restoration of its activity. The structure of the Au–Pd active constituents was studied by transmission electron microscopy X-ray photoelectron spectroscopy. methods of the and microscopy. 相似文献
99.
N. P. Simonenko V. A. Nikolaev E. P. Simonenko N. B. Generalova V. G. Sevastyanov N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2016,61(12):1505-1511
This study is concerned with the preparation of hydrolytically active heteroligand complex [Ti(OC4H9)3.61(O2C5H7)0.39] from titanium butoxide and acetylacetone and with the gel formation kinetics in a solution of this complex upon hydrolysis and polycondensation. Single-layer and double-layer thin films of a solution of this precursor were coated on polished silicon substrates using the dip-coating method. The crystallization of nanostructured titania films during the heat treatment of these xerogel coatings was studied using various protocols; the anatase–rutile phase transition temperature was found to depend on the film thickness. The effects of the precursor solution viscosity on the film thickness and crystallite size were determined. 相似文献
100.
The compensation effect (lgZ=aE+wb) appearing at the thermolysis of one substance under different experimental conditions is discussed. The compensation effect of one and the same substance has no other physical meaning except the simple confirmation of the analytical relationship between lgZ andE that follows from the Arrhenius equation, and of the impossibility to determineZ from any independent experiment. Values of the coefficienta can not be the measure of the ruptured bond strength.
(lgZ=+b), . , lgZ E ( ) Z . a .相似文献