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41.
42.
F. Soška F. Beneš S. Jura B. Gross Z. šimša F. Kosek J. Horák J. Kašpar K. čermák J. Lipták M. Ryba E. F. Holländer A. Havránek E. Havránková A. Kochanovská J. Sommer F. Vilím P. Lukáš C. Rumler S. Kadečková F. Vávra M. Matyáš J. Beneš J. Kučera L. DvoŘák Z. KudĚlásek J. Hájek A. Marek Z. Malec J. Janků B. Sojka L. Karmazin M. Ryšavá L. Janko K. Huml 《Czechoslovak Journal of Physics》1961,11(11):852-862
43.
Ladislav Štourač 《Czechoslovak Journal of Physics》1959,9(6):717-720
, Bi2Te3-Bi2Se3. , , , . .
Influence of ageing on change in electrical properties of semiconducting systems of Bi2Te3-Bi2Se3
The paper describes the effect of ageing observed on a semiconducting system Bi2Te3 — Bi2Se3. It is shown that the change in electrical conductivity and thermoelectric force, which takes place during ageing, is caused by the change in concentration of the free electrons. The influence of this process on the efficiency of equipment employing the Peltier effect is analyzed.相似文献
44.
Stress relaxation test has been used as an indirect method for determination of the velocity-stress exponent for dislocation motion in AgCl single crystals in the temperature range 77 to 423 K. The stress dependence of the velocity-stress exponent has been estimated. A large effect of quenching on the value of the exponent has been found.We wish to thank Dr. F.Vávra for supplying the specimens. 相似文献
45.
46.
Ladislav Adamec 《Applications of Mathematics》2005,50(2):93-101
In the theory of autonomous perturbations of periodic solutions of ordinary differential equations the method of the Poincaré mapping has been widely used. For the analysis of properties of this mapping in the case of two-dimensional systems, a result first obtained probably by Diliberto in 1950 is sometimes used. In the paper, this result is (partially) extended to a certain class of autonomous ordinary differential equations of higher dimension.This research was supported by Grant No. 201/99/0295 of the Grant Agency of the Czech Republic.This revised version was published online in April 2005 with a corrected missing date string. 相似文献
47.
The acetone molecule is investigated in its ground state and valence 1,3n-π*, 1,3π-π*, and 1,3σ-π* excited states and Rydberg 1,3n-3s, 1,3π-3?, 1,3n-3py and 1,3π-3py states using the CASSCF, CASPT2, and CCSD(T) methods. Equilibrium geometries of excited states are obtained and their changes with respect to the ground state are discussed. For most excited states the C2v symmetry of the ground state is lowered to the Cs symmetry. A series of valence vertical and adiabatic excitation energies is presented along with excitation energies for Rydberg states. The main body of the paper contains Finite-Field Perturbation Theory (FFPT) calculations of electric properties of the vertically as well as geometry relaxed excited states. Dipole moments of valence excited states decrease significantly upon excitation, being about one half of the ground state dipole moment. Polarizabilities usually change upon excitation much less (increase by about 30%) but hyperpolarizabilities are enhanced up to one or two orders of magnitude. The orientation of the dipole moment is reversed in some vertically excited Rydberg states. Properties of the ground and excited states are discussed considering alterations of the electronic structure and shifts in the geometry. 相似文献
48.
Ladislav Hlavatý Stanly Steinberg Kurt Bernardo Wolf 《Journal of Mathematical Analysis and Applications》1984,104(1):246-263
Lie series and a special matrix notation for first-order differential operators are used to show that the Lie group properties of matrix Riccati equations arise in a natural way. The Lie series notation makes it evident that the solutions of a matrix Riccati equation are curves in a group of nonlinear transformations that is a generalization of the linear fractional transformations familiar from the classical complex analysis. It is easy to obtain a linear representation of the Lie algebra of the nonlinear group of transformations and then this linearization leads directly to the standard linearization of the matrix Riccati equations. We note that the matrix Riccati equations considered here are of the general rectangular type. 相似文献
49.
Jaffe DE Straub PB Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Glass HD Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review D: Particles and fields》1989,40(9):2777-2795
50.
Ladislav Novotny 《Fresenius' Journal of Analytical Chemistry》1999,363(1):55-58
The adsorption of the polyether-antibiotic monensin from an aqueous solution on mercury was used to investigate the effect
of the decreasing size of a stationary mercury drop electrode on the shape of the voltammetric desorption peak of the surfactant.
The change of the i-E curve indicated an acceleration of the transport of the surfactant to the electrode as well as of time-dependent
changes in the adsorption layer. A decrease of the radius of the hanging mercury drop electrode from 220 μm to 80 μm at a
constant accumulation time of tac = 70 s resulted in an about 4-fold increase of the evaluated signal (i-E pre-wave) of monensin. A 7-fold increase of the
voltammetric desorption peak of monensin at conc. 5 · 10–7 mol/L was observed as result of a compressive accumulation of the surfactant due to a contraction of the mercury drop electrode.
A scheme of an apparatus for voltammetric/polarographic measurements by means of the contractible (compressible) mercury drop
electrode is described. The controlled contraction of the electrode surface is presented together with preliminary results
covering a new way of accumulation of surfactants, new accumulation effects, effective in adsorptive voltammetry, and other
electroanalytical techniques.
Received: 26 March 1998 / Revised: 14 July 1998 / Accepted: 15 July 1998 相似文献