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951.
952.
953.
G. Giardina G. Fazio A. Lamberto A. I. Muminov A. K. Nasirov U. T. Yakhshiev R. Palamara R. Ruggeri 《Acta Physica Hungarica A》2004,19(1-2):101-108
We study the effect of the entrance channel and the shell structure of reacting massive nuclei on the fusion mechanism and the formation of evaporation residues of heavy and superheavy nuclei. In the framework of the combined dinuclear system concept and advanced statistical model, we analyze the reactions 32S+182W, 48Ti+166Er and 60Ni+154Sm leading to 214Th*, and the reactions 48Ca+248Cm and the 48Ca+249Cf leading to the 296116 and 297118 compound nuclei, respectively. 相似文献
954.
V. Babin P. Bohacek E. Bender A. Krasnikov E. Mihokova M. Nikl N. Senguttuvan A. Stolovits Y. Usuki S. Zazubovich 《Radiation measurements》2004,38(4-6):533-537
Luminescence characteristics of a number of undoped and variously doped PbWO4 crystals were studied at 0.4–400 K by the time-resolved spectroscopy and compared with those of ZnWO4,CdWO4 and PbMoO4 crystals. Two types of green emission centres are detected in PbWO4 crystals. The centres of the first type are responsible for the low-temperature 2.3–2.4 eV emission observed under excitation around 3.90–3.95 eV. The structure and parameters of their relaxed excited states were determined. It was concluded that the origin of defects responsible for the green emission of the first type could vary for different crystals. The centres of the second type with the emission around 2.5 eV appear in crystals containing oxygen vacancies after the thermal destruction of Pb+-WO3 centres at T>180 K. Decomposition of the exciton and various defect-related states was also studied, and activation energies of this process were calculated. 相似文献
955.
The F- F+-photoconversion in oxygen-deficient corundum, induced by 210 nm irradiation at different temperatures, was analyzed. It was shown that the dosimetric trap and known deep trap contribute little to these transformations. The dose dependencies of detectors in initial and sensitized states were studied. The interactive processes between different traps in TLD-500 were examined directly. 相似文献
956.
Forces along Equidistant Particle Paths 总被引:1,自引:1,他引:0
Two particles on the sphere leave the equator moving due south and travel at a constant and equal speed along a geodesic colliding
at the south pole. An observer who is unaware of the curvature of the space will conclude that there is an attractive force
acting between the particles. On the other hand, if particles travel at the same speed (initially parallel) along geodesics
in the hyperbolic plane, then the particle paths diverge. Imagine two particles in the hyperbolic plane that are bound together
at a constant distance with their center of mass traveling along a geodesic path at a constant velocity, then the force due
to the curvature of the space acts to break the bond and increases as a quadratic function of the velocity. We consider this
problem for the sphere and the hyperbolic plane and we give the exact formula for the apparent force between the particles.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
957.
Twenty-five years ago, we introduced the phenomenon of negative luminescence (NL) into semiconductor physics. This paper provides an overview of work conducted to develop this fundamental concept. Initially, we consider the first-principle approach to radiation interaction with basic matter and the major properties of NL. Then we describe the problems of NL direct measurements in homogeneous materials and structures. Finally, we emphasize the use of NL approach in applications involving devices for infrared (IR) wavelength (3–12 μm) high-temperature (300–400 K) optoelectronics. Our subjects will include NL IR emitting diodes, radiative coolers, IR dynamic scene simulators, light up-conversion devices, and the Stealth effect in IR. 相似文献
958.
J. Wang G. A. Khodaparast J. Kono T. Slupinski A. Oiwa H. Munekata 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):412
We have used two-color time-resolved magneto-optical Kerr effect spectroscopy to manipulate and detect dynamic processes of spin/magnetic order in a ferromagnetic semiconductor InMnAs. We observed ultrafast photo-induced “softening” (i.e., transient decrease of coercivity) due to spin-polarized transient carriers. This transient softening persists only during the carrier lifetime (2 ps) and returns to its original value as soon as the carriers recombine to disappear. Our data clearly demonstrates that magnetic properties, e.g., coercivity, can be strongly and reversibly modified in an ultrafast manner. We attribute the origin of this unusual phenomenon to carrier-mediated ferromagnetic exchange interactions between Mn ions. We discuss the dependence of data on the pump polarization, pump intensity, and sample temperature. Our observation opens up new possibilities for ultrafast optical manipulation of ferromagnetic order as well as providing a new avenue for studying the dynamics of long-range collective order in strongly correlated many-body systems. 相似文献
959.
Olga V. Man’ko 《Acta Physica Hungarica A》2004,19(3-4):313-316
A short review of the general principles of constructing tomograms of spin and quark states is presented. 相似文献
960.
Recent mass measurements of proton-rich nuclei close to the N=Z line were used for the calculation of the interaction strength δV pn between valence protons and neutrons. When compared with δV pn values calculated from mass values of the AME’95 mass tables, the breaking down of the SU(4) symmetry is verified at Z=32,33,34. 相似文献