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991.
Karol Jankowski Janina Muszyńska Andrzej Rutkowski 《Theoretical chemistry accounts》1978,47(4):275-282
The Galerkin-Petrov method is applied to the determination of the ground state energy of the beryllium atom. The basis set of the coordinate subspace consists of correlated wavefunctions of the combined configuration-interaction-Hylleraas type. The basis set of the projective subspace is of the configuration-interaction type. The usefulness of a previously proposed way of characterization of pairs of subspaces has been further confirmed. Experience in constructing close pairs of subspaces gathered in the case of two-electron systems is used for the larger system. Two methods for constructing pairs of subspaces are used in the calculations. 相似文献
992.
The paper is concerned with a set of linear differential equations with time-dependent parameters given by trigonometrical series. Derived formulas make it possible to examine stability, to find boundaries of the regions of instability and to estimate the steady state response amplitude of forced vibrations. 相似文献
993.
Bogdan Ptaszyński 《Thermochimica Acta》1980,38(3):277-283
Thermal studies have been carried out on crystalline complexes formed between antimony(III) bromide and hydrobromides of some aromatic amines in concentrated hydrobromic acid solutions. Thermal analysis curves of the compounds under study are presented. Kinetic parameters of the thermal decomposition reactions were calculated from the TG curves using the Horowitz—Metzger method. A comparison of the thermal stabilities of the complexes was made. 相似文献
994.
995.
Uniaxial stress experiments were used to investigate the nature of the luminescence lines observed at low temperatures in ZnTe in the vicinity of the absorption edge. The single crystals used in this experiment were grown from solution of ZnTe in tellurium. Both “as-grown” crystals and crystals annealed in Zn vapour were investigated. The most intense line in “as-grown” crystals is attributed to an exciton bound to a neutral acceptor. The binding energy of the exciton in this center is 6 meV. After annealing a new center appears in the same spectral region. Stress experiments as well as the temperature dependence of the intensity of the luminescence indicate that this center is a complex consisting of an exciton and an ionized donor. Splitting of J = 1 (Γ5) and J = 2 (Γ3 + Γ4) levels was found to be 1.2 meV. 相似文献
996.
The second-order intensity correlation function g(2)(0) of a laser beam passing through a nonlinear medium has been experimentally found to be a decreasing function of the power density in the medium. 相似文献
997.
A. Budzanowski K. Chyla R. Czabański K. Grotowski L. Jarczyk B. Kamys A. Kapus̀cik S. Micek J. Płoskonka A. Strzałkowski J. Szmider Z. Wróbel L. Zastawniak R. Zybert 《Nuclear Physics A》1973,211(3):463-472
Excitation functions for the elastic scattering of α-particles from Ni, Co and Cu at θlab = 179° were measured in the lab energy range 22.75–28.40 MeV, as well as some angular distributions for Co(α, α). Broad maxima with a width of about 2.5 MeV were found in the excitation functions. It is shown that a simple four-parameter optical model of the interaction is able to reproduce the angular distributions as well as the excitation functions. Examination of the Argand diagrams leads to the conclusion that the maxima in the excitation curves are formed as a result of a coherent superposition of a number of partial waves, none of which behaves in itself in a resonance-like manner. 相似文献
998.
M. Szymański J. Karolczak F. Kaczmarek 《Applied Physics A: Materials Science & Processing》1979,19(3):345-351
PrP5O14, PrxLa1−xP5O14, and PrxY1−xP5O14 (0≦x≦1) single crystals of laser quality were synthesized and their crystallographic and optical parameters measured. Laser
emissions in the visible (λ=637.4 nm) with no mirrors in place (superradiance) and also in various optical resonators have
been observed. 相似文献
999.
The Cerofolini procedure for obtaining multilayer adsorption isotherms on heterogeneous surfaces is generalized, to take into account the full form of the BET equation as the local adsorption isotherm. 相似文献
1000.
U. Domańska 《Journal of solution chemistry》1989,18(2):173-188
Three long-chain ethylene glycol monoesters of stearic, eicosanoic and behenic acids have been synthesized and carefully purified. Their solubilities in 25 pure solvents and in 28 binary solvent systems have been investigated by a synthetic method over a temperature range from 280 to 320 K. The systems containing cyclohexane+alcohols and chlorohydrocarbons+alcohols mixed solvents were found to exhibit a solubility synergistic effect. The results of these measurements were correlated by the Wilson equation utilizing temperature dependent ij parameters. 相似文献