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991.
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994.
I. G. Zenkevich 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(10):1636-1642
A new approach to calculating the temperatures of boiling at atmospheric pressure (T b) of organic compounds from arbitrary homologous series is suggested. The approach is based on the linear dependence of these values on T b for the preceding homologues, T b(n) = aTb(n ? 1) + b. This dependence, revealed for the first time, was used to obtain a recurrence relation for calculating T b of organic compounds within any series from the data on three simpler homologues of the same series. The mean a and b values can be used to estimate T b of an arbitrary organic compound from T b for one preceding homologue with an accuracy not inferior to that provided by the modern ACD software. Correlations of the general form P(n) = aP(n ? 1) + b are observed not only for the boiling points of organic compounds but also for their other properties P (refractive indexes, relative densities, and ionization energies). This opens up the possibility of creating unified algorithms for calculating various physicochemical constants of organic compounds instead of particular algorithms for every particular property known earlier. 相似文献
995.
G. G. Demirkhanyan 《Optics and Spectroscopy》2006,101(4):546-548
A scheme of calculation of line strengths for indirect electric dipole transitions between Stark states of impurity ions in dielectric crystals is proposed. It is shown that knowledge of the three semiphenomenological Judd-Ofelt parameters of a crystalline system is sufficient for quantitative calculations. The formulas obtained were approved for YAG:Nd3+ crystals based on calculation of the spectroscopic characteristics of the lines of the inter-Stark transitions 4 F 3/2 → 4 I 9/2 and 4 F 3/2 → 4 I 11/2. 相似文献
996.
H.G.C. Human N.P. Ferreira C.J. Rademeyer P.K. Faure 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(7):593-602
A method and computer program were developed for calculating the temperature of any part of a graphite furnace tube at any instant of time after onset of the heating cycle. Results for tubes of the Massman design show large differences in spatial temperature distributions during and at the end of the heating cycle when equilibrium is reached. When constant current is applied to contoured tubes, greater heating rates at the tube centres are obtained than with standard tubes. 相似文献
997.
Proceedings of the Steklov Institute of Mathematics - 相似文献
998.
Epitaxial and c-axis oriented double perovskite Sr2CrWO6 thin films were prepared on SrTiO3 (100) and LaAlO3 (100) substrates by pulsed-laser deposition. Structural, magnetic and transport properties were found to be sensitive to the gas conditions employed during the deposition. A small amount of oxygen along with Ar during the deposition was found to be essential for B-site ordering; such films displayed lattice parameters close to the bulk value and display ferromagnetic metallic behavior. The Curie temperature observed above 500 K in these films is higher than bulk Sr2CrWO6 samples. Films grown without oxygen were observed to have long c-parameter and no B-site ordering; they were non-magnetic and semiconducting. 相似文献
999.
M. V. Davidovich 《Radiophysics and Quantum Electronics》2006,49(3):210-219
We propose a method which transforms homogeneous integral equations into inhomogeneous ones for problems of diffraction by
semi-infinite structures. New integral equations and the corresponding stationary functionals dependent on the desired scattering
parameters are obtained. The consideration is performed for the open-end diffraction problem of a parallel-plate waveguide
which has a rigorous solution, but the method has sufficient generality to use it for two-dimensional surface integral equations
describing planar and nonplanar structures as well as for an arbitrary structure of waveguide transformer type, the solution
for which can be sought in the finite domain. The method is based on field representation at the infinity as incident and
scattered waves.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 3, pp. 235–245, March 2006. 相似文献
1000.