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991.
992.
M. Liang H. Ohm B. De Sutter K. Sistemich B. Fazekas G. Molnär 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):223-224
The half-lives of low-lying levels of the neutron-rich isotopes102Mo and104Mo have been measured at the fission product separator Josef with the ß-- triple coincidence technique. Values of t1/2= 126(4)ps and 0.72(4)ns have been obtained for the 21
+ levels at 296 keV and 192 keV in102Mo and104Mo, respectively. Deformation parameters of ßq=0.28(1) and 0.31(1), respectively, are deduced, which are smaller than those of the isotones of Sr and Zr. The interacting boson model accounts well for the trend of 2+ energies in the Mo isotopes but slightly overpredicts the B(E2) values at saturation. A smooth dependence of 21
+ vs. E 21
+ is found for the A 100 region in agreement with the hydrodynamical model.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday 相似文献
993.
We present a multipass femtosecond amplifier pumped by a Nd-YAG laser where the gain medium is given by a variable length dye cell. This system allows amplification factors up to 5 · 106 and output pulse energies of 150 J, while restricting the contribution of amplified spontaneous emission to 0.5% of the total output energy, without using any saturable absorber stage. A detailed study of the output pulsewidth as a function of the duration of the input chirped pulse is also presented. 相似文献
994.
995.
996.
Mori M Oyama Y Suzuki A Takahashi K Yamada M Miyano K Miyata H Takei H Hirata KS Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Koshiba M Suda T Tajima T Fukuda Y Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,43(9):2843-2846
997.
998.
The kinetics of substitution of aqua ligands fromcis-[Ru(bipy)2(H2O)2]2+ ion by salicylhydroxamic acid (L) in aqueous medium has been studied spectrophotometrically at different temperatures (50–65°C).
The following rate law has been established in the pH range 4.0 to 5.8;
相似文献
999.
Sidney Coleman Lawrence M. Krauss John Preskill Frank Wilczek 《General Relativity and Gravitation》1992,24(1):9-16
A black hole may carry quantum numbers that arenot associated with massless gauge fields, contrary to the spirit of the no-hair theorems. The quantum hair is invisible in the classical limit, but measurable via quantum interference experiments. Quantum hair alters the temperature of the radiation emitted by a black hole. It also induces non-zero expectation values for fields outside the event horizon; these expectation values are non-perturbative in , and decay exponentially far from the hole. The existence of quantum hair demonstrates that a black hole can have an intricate quantum-mechanical structure that is completely missed by standard semiclassical theory.Based on an essay which received second award from the Gravity Research Foundation, 1991 相似文献
1000.
J. Demaret Y. De Rop P. Tombal A. Moussiaux 《General Relativity and Gravitation》1992,24(11):1169-1183
The Einstein-like field equations obtained from the variation of a Lagrangian containing linear, quadratic (Gauss-Bonnet) and quartic terms for a ten-dimensional cosmological model cannot be solved analytically. However, we can reduce them to a system of dynamical equations for the Hubble parameters. The study of the mathematical properties of the fixed points of this system gives a qualitative picture of the behaviour of a class of possible solutions. The inclusion of a quartic term generates an extremely rich structure for the corresponding dynamical system. Some solutions are shown to exhibit the interesting property of dimensional reduction, which has been proposed as a possible explanation of the three-dimensional character of our universe. 相似文献
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