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71.
A possibility is proposed for studying changes in the electronic characteristics of surface defects in adsorption and catalysis, using conductivity measurements in the region of injection currents. The change in the spectrum of electron traps is interpreted by a coordinative mechanism of adsorption.
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An experimental study was made of the Raman scattering spectra of more than 20 organic compounds in the polycrystalline state over a broad temperature range in the frequency range 20–150 cm–1. General features are found in the temperature dependence of the line frequencies and widths: coalescence of lines into bands, spectral blurring, intensity redistribution, etc. At liquid-nitrogen temperature the number of low-frequency lines is consistent with the Born theory, while at high temperatures (how high depends on the particular substance) the orientational disorder of a crystal strongly affects the spectrum.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 2, pp. 75–83, February, 1971.  相似文献   
74.
A series of relations are given for the domains of attraction of limiting distributions and the corresponding centralizing and normalizing constants for extremal order statistics, record values, and some generalizations of record values.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 166, pp. 103–111, 1988.  相似文献   
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Physics of Atomic Nuclei - An attempt is made to explain the tiny order of magnitude of the cosmological constant in a model involvingt he following ingredients: supersymmetry breaking in N = 1...  相似文献   
77.
We consider the renormalisation group flow of gauge couplings within the so-called exceptional supersymmetric Standard Model (E6SSM) based on the low-energy matter content of 27-dimensional representations of the gauge group E6E6, together with two additional non-Higgs doublets. The two-loop beta functions are computed, and the threshold corrections are studied in the E6SSM. Our results show that gauge coupling unification in the E6SSM can be achieved for phenomenologically acceptable values of α3(MZ)α3(MZ), consistent with the central measured low-energy value, unlike in the minimal supersymmetric Standard Model (MSSM) which, ignoring the effects of high energy threshold corrections, requires significantly higher values of α3(MZ)α3(MZ), well above the experimentally measured central value.  相似文献   
78.
Thermodynamic limit of magnetization corresponding to the intact proton bath usually cannot be transferred in a single cross-polarization contact. This is mainly due to the finite ratio between the number densities of the high- and low-gamma nuclei, quantum-mechanical bounds on spin dynamics, and Hartmann-Hahn mismatches due to rf field inhomogeneity. Moreover, for fully hydrated membrane proteins refolded in magnetically oriented bicelles, short spin-lock relaxation times (T1ρ) and rf heating can further decrease cross polarization efficiency. Here we show that multiple equilibrations-re-equilibrations of the high- and low-spin reservoirs during the preparation period yield an over twofold gain in the magnetization transfer as compared to a single-contact cross polarization (CP), and up to 45% enhancement as compared to the mismatch-optimized CP-MOIST scheme for bicelle-reconstituted membrane proteins. This enhancement is achieved by employing the differences between the spin-lattice relaxation times for the high- and low-gamma spins. The new technique is applicable to systems with short T1ρ's, and speeds up acquisition of the multidimensional solid-state NMR spectra of oriented membrane proteins for their subsequent structural and dynamic studies.  相似文献   
79.
The asymptotic properties and structure of bootstrapping maxima and record values are investigated. Bibliography: 19 titles.  相似文献   
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