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731.
N. Matsuo 《Zeitschrift fur Physik C Particles and Fields》1987,36(2):289-304
The thermodynamics of superstring theories (SST-I, SST-II and heterotic string theory) and its application to the cosmology are studied. The free energy of superstring gas is calculated in the one-loop approximation and the stability of the extra torus dimensions is discussed. Assuming that the Einstein equation dictates the evolution of the universe, we show that matter dominated universe filled with massive particles would never be realized at the beginning of the universe, contrary to the naive expectation in the superstring cosmology. 相似文献
732.
733.
Resonance Raman scattering by exciton polaritons in crystals of CuGaS2 under excitation with the 4880 and 4765 Å lines of an Ar+ laser at 9 K is studied. Lines of one-and two-phonon scattering of excitonic polaritons are found and studied. It is shown that the 1LO and 2LO phonons are arranged in accordance with their energies as the Stokes shifts move farther away from the excitation energy. 相似文献
734.
V. S. Antonov V. S. Letokhov A. N. Shibanov 《Applied Physics A: Materials Science & Processing》1981,25(1):71-76
The paper presents the results of studies into ion desorption from the surface of adenine and anthracene molecular crystals
and anthracene molecules adsorbed on a metal as the surface is irradiated by an uv laser at λ=249, 308, and 337 nm. A sharp
increase in molecular ion yield has been revealed with a decrease in radiation wavelength down to 249 nm. At this wavelength
the effect of molecular ion desorption is observed at the radiation intensity of 20∶50 kW/cm2 and pulse duration of 20 ns, it cannot be explained by thermal mechanisms. The initial velocity distribution of photoions
is nonthermal by character, with maximum velocity of 2·105 cm/s in case of adenine. The mechanisms responsible for the effect observed are discussed. 相似文献
735.
Reported to the 5th All-Union Conference on High-Temperature Plasma Diagnostics (June 18–22, 1990, Minsk). 相似文献
736.
V. N. Volynets D. I. Slovetskii A. Ya. Strochkov V. N. Trofimov 《Journal of Applied Spectroscopy》1991,54(6):613-619
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 1004–1010, June, 1991. 相似文献
737.
N. G. Marchuk 《Russian Journal of Mathematical Physics》2006,13(4):397-413
With the help of the apparatus of tensors with values in the Atiyah-Kähler algebra (the apparatus of lambda tensors), a new representation for the relativistic equation of field theory is proposed. The circle of questions under consideration is standard for investigations concerning the theory of the Dirac equation (in this paper, we treat no problems dealing with second quantization). 相似文献
738.
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