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931.
932.
933.
934.
The study of the effect of a perfectly conducting plane placed at a certain distance from the surface of a potassium niobate crystal on the characteristics of the generalized Rayleigh and Gulyaev-Bleustein surface waves is continued. In addition, the effect of an infinitely thin conducting layer applied to the surface of the piezoelectric on the characteristics of these waves is analyzed. It is found that a variation in the conductance of this layer can produce a result that completely differs from the result obtained when a perfectly conducting plane is moved toward the surface, although the extreme states of these actions (electrically open and short-circuited surfaces) are identical. A possible physical explanation of this difference is proposed.  相似文献   
935.
Thermoelectric effects are investigated theoretically in layered conductors with a quasi-two-dimensional electron energy spectrum of arbitrary type in a strong magnetic field. It is shown that, at temperatures sufficiently low for quantization of the orbital motion of charge carriers in a magnetic field to be required, there exist giant quantum oscillations of the thermoelectric field. Thermoelectric emf is studied as a f unction of the orientation of the magnetic field with respect to the layers; experimental investigation of this function allows one to determine the velocity distribution of conduction electrons on the Fermi surface.  相似文献   
936.
The mechanisms leading to instability of the non-Fermi-liquid state of a Luttinger liquid with two-level impurities are proposed. Since exchange scattering in 1D systems is two-channel scattering in a certain range of parameters, several types of non-Fermi-liquid excitations with different quantum numbers exist in the vicinity of the Fermi level. These excitations include, first, charge density fluctuations in the Luttinger liquid and, second, many-particle excitations due to two-channel exchange interaction, which are associated with band-type as well as impurity fermion states. It is shown that mutual scattering of many-particle excitations of various types leads to the emergence of an additional Fermi-liquid singularity in the vicinity of the Fermi level. The conditions under which the Fermi-liquid state with a new energy scale (which is much smaller than the Kondo temperature) is the ground state of the system are formulated.  相似文献   
937.
Deeper insight into the features of a reactor as a source of antineutrinos is required for making further advances in studying the fundamental properties of the neutrino. The relationship between the thermal power of a reactor and the rate of the chain fission reaction in its core is analyzed.  相似文献   
938.
A phenomenological model for describing the production of Centauro events in relativistic heavy-ion collisions is discussed. The model provides quantitative predictions for kinematical variables, for the baryon number, and for the masses of a Centauro fireball and of its decay products. A Centauro fireball decays predominantly into nucleons, strange hyperons, and possibly strangelets. Centauro events in Pb + Pb collisions at the LHC energy are simulated for the CASTOR detector. The signatures of these events are discussed in detail.  相似文献   
939.
New results concerning the topology of the fragmentation of relativistic nuclei 7Li and 10B are presented. A program is proposed for studying the cluster structure of stable and radioactive nuclei. The use of emulsions in the investigation of nuclear clustering in the fragmentation of light nuclei at energies are in excess of 1 GeV per nucleon is discussed.  相似文献   
940.
In 1994, the International Atomic Energy Agency (IAEA) initiated a 5-year Co-ordinated Research Project (CRP) to determine geographical and racial differences in peak bone mineral density (BMD) in men and women aged 15-49 years. The study demonstrates that there are distinct global differences in BMD at the hip and spine in both men and women approximating to one population standard deviation between populations with the highest and lowest BMD. These differences persist following adjustments for age, sex and body size. Such information is valuable in understanding the reasons for global differences in fracture rate and predicting future trends in fracture incidence. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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