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991.
Relationships between the electrodynamic (wave propagation constants) and quantum-mechanical parameters (probability of induced transitions) of interaction between energy quanta and particles of the medium are derived for dipole and paramagnetic interaction types. It is demonstrated that quantum-mechanical parameters are generally complex.  相似文献   
992.
Aromatic nitro compounds were reduced to the corresponding symmetrically substituted azo compounds using lead as catalyst and triethylammonium formate as hydrogen donor. Various azo compounds containing additional reducible substituents including halogens, nitrile, acid, phenol, ester, methoxy functions, etc, have been synthesized in a single step by the use of this reagent. The conversion is reasonably fast, clean, high yielding and occurs at room temperature in methanol.  相似文献   
993.
We prove that any irreducible faithful representation of an almost torsion-free Abelian group G of finite rank over a finitely generated field of characteristic zero is induced from an irreducible representation of a finitely generated subgroup of the group G.  相似文献   
994.
Influence exerted by additives introduced into the working solution, by iron or copper formedin electric-spark dispersion of these metals and zinc, on the quality of the products obtained in electric erosionwas studied.  相似文献   
995.
The structure, harmonic frequencies, and nonresonance Raman intensities for porphin, tetraazaporphin (TAP), and three of its isotopomers are calculated by the density-functional theory of B3LYP/6-31G(d). Scaling of force constants for porphin in nonredundant natural coordinates is performed. The scaling factors obtained were used to predict the force field and normal modes of TAP and three of its isotopomers. Two alternative methods are used to carry out reliable assignment of the TAP frequencies: wavenumber-linear scaling method and frequency-shift method. There is good agreement between the frequencies predicted within the framework of the three methods used. The conservativeness of the out-of-plane B 2g - and B 3g -modes for porphin and TAP is examined. The Raman spectrum for TAP is simulated. A refinement of the assignment of the experimental frequencies for TAP of even symmetry types on the basis of the calculations performed is made.  相似文献   
996.
A previously developed laser spallation technique has been modified to measure the tensile strength of thin film interfaces in-situ at temperatures up to 1100°C. Tensile strengths of Nb/A-plane sapphire, FeCrAl/A-plane sapphire and FeCrAlY/A-plane sapphire were measured up to 950°C. The measured strengths at high temperatures were substantially lower compared with their corresponding strengths at ambient temperature. For example, at 850°C, the interface tensile strength for the Nb/sapphire (151 ± 17 MPa), FeCrAl/sapphire (62 ± 8 MPa) and FeCrAlY/sapphire (82 ± 11 MPa) interface systems were lower by factors of approximately, 3, 5, and 8, respectively, over their corresponding ambient values. These results underscore the importance of using such in-situ measured values under operating conditions as the failure criterion in any life prediction or reliability models of such coated systems where local interface temperature excursions are expected. The results on alloy film interfaces also demonstrate that the presence of Y increases the strength of FeCrAl/Al2O3 interfaces.  相似文献   
997.
The fine-structure parameters of a series of configurations of the first ion of indium and the gyromagnetic ratios in intermediate coupling are calculated by a semiempirical method in the single-configuration approximation.  相似文献   
998.
999.
The slip velocity of a rarefied gas nonuniform in temperature and mass velocity is calculated for gas slip over the surface of a right circular cylinder. The calculation uses the two-moment boundary condition in an approximation linear in Knudsen number. Corrections to the slip velocity that are due to the interface curvature, volume temperature stresses, and nonuniform temperature distribution in the Knudsen layer are studied as func-tions of the accommodation coefficients in the first two moments of the distribution function. The Bhatnagar-Gross-Krook model of the Boltzmann kinetic equation is employed as the basic equation for the gas state.  相似文献   
1000.
Nicholas Nathan tries to resist the current version of the causal argument for sense-data in two ways. First he suggests that, on what he considers to be the correct re-construction of the argument, it equivocates on the sense of proximate cause. Second he defends a form of disjunctivism, by claiming that there might be an extra mechanism involved in producing veridical hallucination, that is not present in perception. I argue that Nathan’s reconstruction of the argument is not the appropriate one, and that, properly interpreted, the argument does not equivocate on proximate cause. Furthermore, I claim that his postulation of a modified mechanism for hallucinations is implausibly ad hoc.  相似文献   
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