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1.
Using the semiempirical method of partial neglect of differential overlap (PNDO), we have calculated the wave functions, energies, orbital configurations of electronic states, oscillator strengths of transitions, electronic density distributions, and dipole moments for the molecule of biologically active 8–azagona–12,17–dione, containing a conformationally rigid –acyl––aminovinylcarbonyl fragment. It has been established that as to their orbital nature the excited lower and higher singlet electronic states of this molecule are of the n*– and * type respectively. The results of the theoretical analysis are in good qualitative agreement with the spectral data on absorption and luminescence. The calculations of the intermolecular interaction of the compound under consideration with a medium show that the molecular systems under consideration can possess a dynamic multicenter structure.  相似文献   

2.
Conclusions We have examined the absorption spectra of DS and the dependence of the quantum yield in photodissociation of DC on exciting wavelength, which has shown that the electronic structure of DC allows one to observe *transitions and also n* and * ones, with the a orbital localized on the dissociating C-N bond. The formation of long-lived3(*) excitation leads the DC to dissociation into a neutral nitrogen molecule and an ary1 cation in the triplet state.Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 41, No. 5, pp. 803–809, November, 1984.  相似文献   

3.
A heuristic model for deriving the anomalous magnetic moment of the electron is presented. A term /2 – 0.327(/)2 is deduced, in better agreement with experiment than is the QED derivation of /2 – 0.328(/)2. The result is strengthened by the recent non-QED account of the Lamb shift by Yu and Sachs.  相似文献   

4.
The s-wave pion scattering amplitude is analysed with the aim to clarify the mass spectrum of scalar mesons and to find evidence of lightest glueball. The S-matrix and K¯K coupled channel formalism is used. The existence of scalar mesons S* and is implied by the data. The production K¯K and the elastic K¯KK¯K coupled amplitudes are predicted from the scattering data. The couplings c f S* to and K¯K states are determined.  相似文献   

5.
The method of complex angular moments is used to analyze the experimental data on the inelastic reactions p ()K, taking into account branch cuts in the j-plane in the eikonal approximation. An optical model for the backward scattering is considered. Agreement with experiment is obtained in the region of small angles for the reactions (0)K0. In the case of P K0(K+) processes, agreement is obtained with the experimental results for large (180) scattering angles.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 26–30, August, 1972.  相似文献   

6.
Conclusions We have presented soms of our preliminary results on the coupled NN-NN problem. The overall result obtained so far is rather encouraging and we are currently making the model more sophisticated in order to be able to make more quantitative arguments which may hopefully serve somehow to clarify the dibaryon resonance problems. To end we would like to emphasize that since all the channels (viz.d d, d NN, NN NN, etc.) are unitarily coupled, one cannot arbitrarily change some input parameters to attain a better fit in one of the channels alone: all the channels are closely linked, which serves as a very strong constraint to the input. In near future we wish to extend our model to calculate processes with three-body final statesWork supported in part by Bundesministerium für Forschung und Technologie.Invited talk at the symposium Mesons and Light Nuclei, Liblice, Czechoslovakia, June 1981.I am grateful to my collaborators, Y. Avishai, C. Fayard, G. -H. Lamot and S. Nahabetian for numerous discussions.  相似文献   

7.
We have investigated the luminescent properties of -anions in Zn and Pd complexes of octaethylporphin and etioporphyrin, and also of protonation products of -dianions (-monoanions of phlorins). It is established that the quantum yield of luminescence of -anion radicals in Zn complexes amounts to 2.9·10–4. The lifetime of the lower excited (doublet) state is estimated to be 120 ± 25 nsec. We failed to reveal the luminescence of -dianions. In reducing the Pd porphyrins into -anion radicals and -dianions, a loss of the luminescent properties is observed. However, the -monoanion of phlorin in Pd octaethylporphin luminesces. The Zn complex of the phlorin anion also has the same properties. The spectral properties of Zn and Pd phlorin anions are similar: a large Stokes shift is observed at room temperature; on decrease in the temperature to 77 K the fluorescence spectrum becomes narrower, the maximum of the spectrum shifts strongly to the blue region, and the quantum yield of luminescence increases. The special features of the spectral properties of phlorin anions are explained by conformation changes in the excited state. It is found that in a solution at room temperature Pd phlorin anions quench the phosphorescence of neutral Pd porphyrins.  相似文献   

8.
The paper considers the processes of formation of pseudoscalar mesons by the interaction of an antineutrino with a leptonv ll K, , K.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 139–143, August, 1974.  相似文献   

9.
In this paper the magnetic properties of ferromagnetic thin layers are studied by calculating the partition function for the magnetic system inKirkwood's approximation of the second order. The results obtained for the Curie temperature and the magnetization are in somewhat better agreement with the experiment than those obtained by Valenta.
. , , .


The author extends his thanks to the group of research workers who performed the numerical calculation of the Curie temperatures on the computer CIFA 1, as well as gratitude to Dr. l. Valenta for so kindly supplying information on the results of his investigations on the same subject.  相似文献   

10.
A thickness dependence of the permittivity ofc-domain barium titanate single crystals was found. The experimental results were explained by means of a model of a dielectric with surface layers. The thickness of the layer and the permittivity of the surface layer and bulk of the crystal were determined.
iO3
iO3, -. . , .
  相似文献   

11.
We study the Sine-Gordon field theory at 2=8. We prove that the theory is renormalizable but not superrenormalizable and we show how the perturbative renormalization procedure works in this case where the interaction is not polynomial. To go beyond the perturbative results we investigate the -functional equation for this theory and discuss in what sense at 2=8 the theory is lacking the asymptotic freedom and how it is asymptotic free for 2<8 in a appropriate region of the coupling constants.  相似文献   

12.
The article presents the results of an investigation of the quantum yield and absolute population of the vibrational levels of electronically excited states A2 (v 25), B2 (v 15) of the CN radical and B3g (v 12) of the N2 molecule in nitrogen-helium afterglow cooled by liquid nitrogen at a total pressure of the mixture of (12–20) mm Hg. The rotational temperature of the cold gas was measured. The content of carbon impurity in the system was measured by the spectral method. A study was made of the kinetics of the decay of afterglow, from which the relaxation time was determined and the cross section of exchange of vibrational quanta between N2 and CN molecules was estimated. The data obtained were compared with the results of investigating nitrogen-helium afterglow under room-temperature conditions.300th Anniversity of Reunion of Ukraine with Russia Dnepropetrovsk State University.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 52–59, April, 1976.  相似文献   

13.
The physical nature of the stratification of the d-c discharge plasma is found and physically interpreted. The interpretation is based on the mathematical expression of the production of periodic structure in plasma after an aperiodic disturbance, derived from an extremely simplified system of equations. Only three basic phenomena occurring in the plasma of each d-c discharge are included: a) the dependence of the rate of ionization on the electron temperature and hence on the electric field, b) the production of space charges due to the different rates of diffusion of the electrons and ions, c) the creation of additional electric fields due to the creation of space charges. The interactions of these phenomena gives rise to a chain, expanded in time and space, which leads to the production of moving striations. In agreement with experiment this structure is developed only on the side towards the anode from the place where the equilibrium state is disturbed.
. (9, 10) (4, ), . , , : ) , , ; ) , ; ) , . , , — — . , .


In conclusion the authors thank J. Fousek, J. Kaczér and M. Novák for carefully reading this paper and for valuable remarks, and J. Holub for carrying out the numerical and graphical work.  相似文献   

14.
The long-wave * transitions and weak n * transitions are discussed for several compounds of practical importance. Wave functions are presented for aliphatic ketones, acids, and esters.  相似文献   

15.
The instability of spin waves at ferromagnetic resonance is discussed. An equation of the stationary state of spin wavesk0 is derived by means of the quantum theory of spin waves. It is shown when discussing this equation that the concept of the critical uniform precession angle may be obtained when using an approximation which neglects the action of spin wavesk0 backward on their own excitation. We believe we are justified in supposing that, due to this effect, a stable stationary state can exist even above the critical amplitude of uniform precession, given by theories up to now.
. k0. , , k0 . , , , , .


In conclusion the author thanks G. A. Smolenskij for enabling him to carry out this work in his laboratory. Thanks also go to the theoretical staff of the Institute of Semi-conductors of Acad. Sci. USSR in Leningrad for valuable discussions, especially to A. I. Anselm, V. L. Gurevic and J. A. Firsov.  相似文献   

16.
The paper solves the problem of gas ionization in a discharge path in a very dilute gas, where the free path of the electrons is much larger than the dimensions of the path and the transit time of the electrons between the electrodes is of the order of the period of the applied h-f voltage. It was found that for a certain ratio of the transit time of the electrons between the electrodes in the discharge path to the period of the h-f oscillation, resonance occurs when the wattless current component is zero. The electron density rises in the path and thus also the gas ionization.
, , , . , , . , .


In conclusion, the author would like to thank F. Benda for preparing the equipment, M. Kivánek for preparing the equipment and some of the measurements, and A. Hrdá for the measurements and for working out the case with equally large a-c and d-c voltages within the framework of her thesis.  相似文献   

17.
In paper [1] Fang derived an expression for the complex conductivity of plasma assuming that the distribution function of the electrons is Maxwellian and the collision frequency is directly proportional to their velocity. Since the assumptions are approximately satisfied in the positive column of a d-c glow discharge in Ne, the applicability of Fang's relation is investigated for this case.
[1] , . , .
  相似文献   

18.
A Bloch wall has an integral magnetic moment which is due to the spatial distribution of the magnetic moments of the spin. The external magnetic field thus acts on the wall with a torque, which leads to the rotation of the sub-domains and therefore to deformation of the walls. A theory of this rotation is given and from it a microphysical model of the undulatory surface structure in uniaxial ferromagnets is derived. Experiments performed on magnetoplumbite single crystals fully confirm the theoretical assumptions.
. , , . , . , , .


Our thanks go to J. Fousek and Z. Málek who by reading this paper contributed greatly to the clarity of its presentation.  相似文献   

19.
The possible ways of drawing of the intensity of the S0 T* transition in the chlorobenzene molecule are investigated. The effective spin-orbit coupling of either S* or S* states with the T* state leads to the out-of-plane polarized component of phosphorescence in the chlorobenzene. The in-plane polarized component cannot be explained by the mechanism under consideration — by drawing of intensity of the S0 S0* transitions through spin-orbit coupling of first order.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 134–138, August, 1974.  相似文献   

20.
The Gelfand-Levitan equation for the kernelP(r, r) (withrr) is formulated and then applied for determining the scattering potential in the scattering of slow neutrons on protons (for the case when the dependence of the nuclear forces on the spins can be neglected and onlys-scattering need be considered). The potentials obtained are the same as the Bargmann ones, found by a different method.
-
- P(r, r) ( rr). , ( s- ). , .
  相似文献   

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