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991.
Prof. Dr. Miloš Zlámal 《Numerische Mathematik》1970,14(4):394-402
A finite element procedure of the second order of accuracy for solving second order boundary value problems is presented and justified and numerical results are given. 相似文献
992.
In this experimental study the absorption of plasma waves, excited in a dense plasma column, was investigated and the localization of the regions of efficient heating of electrons were determined in a broad range of parameters: 1>ce/>0·1, 0·3<n/n
UH
<25, 10–5<v/< <10–3. The heating of electrons near the second electron cyclotron harmonic was investigated in greater detail.We are grateful to the members of the Staff of the Institute of Plasma Physics Drs. P.unka, R.Klí'ma, V.Kopecký, J.Musil for discussion of the results. We also thank Drs. J.Musil, F.áek for the help and advice in the early stages of experimental work during construction of different diagnostic devices. Our thanks are due to the director of the Institute Dr. J.Váa for encouraging support of this experimental program. 相似文献
993.
Implications of Weinberg's algebraic relations when only p-wave pions are taken into account are investigated. It is shown that decay rates and mass spectra of hadrons assigned to certain classes of unitary irreducible representations of theSU(4) group are in a strong disagreement with experimental data. 相似文献
994.
995.
996.
Exchange and correlation contributions to the vacuum part of the effective electron potential of a semiinfinite crystal are modelled by a simple shifted image potential. Modifications, introduced by this potential, are studied for the cases of electron surface states and of the diffraction of low-energy electrons on a simple one-dimensional model. 相似文献
997.
998.
Zvonimir B. Maksić Krešimir Kovačević Andrea Moguš 《Theoretical chemistry accounts》1980,55(2):127-132
A comparative study of the structural parameters in some strained spirohydrocarbons is presented. The theoretical values provided by the STO-3G, MINDO/3 and IMOA methods are in reasonable agreement with each other and with available experimental data offering thus a posteriori justification of the employed approximate schemes. 相似文献
999.
S.P. Belov L.I. Gershstein A.F. Krupnov A.V. Maslovskij Š. Urban V. Špirko D. Papoušek 《Journal of Molecular Spectroscopy》1980,84(1):288-304
Using the vibration-inversion-rotation Hamiltonian for ammonia [V. ?pirko, J. M. R. Stone, and D. Papou?ek, J. Mol. Spectrosc.60, 159–178 (1976)], a modified theory is worked out for the Δk = ±3n interactions between the inversion-rotation energy levels of NH3 which takes into account the large amplitude inversion motion. Eighty frequencies of inversion and inversion-rotation transitions and two perturbation-allowed transitions in the ν2 state of 14NH3 are measured in the far-infrared region around 1 THz (≈33 cm?1), mostly with the microwave accuracy, by the radiofrequency spectrometer with acoustic detector. By a least-squares fit of these data and the data of the infrared-microwave two-photon and infrared heterodyne measurements of the ν2 band, a set of molecular constants for the ν2 state of 14NH3 is obtained which reproduces the submillimeterwave data with the accuracy of the experiment. 相似文献
1000.