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991.
Energy levels: 1s 1/2, 2p 1/2, 2p 3/2, 3d 3/2, and 3d 5/2 of the muon in the spherical nuclei:120Sn,197Au and208Pb have been calculated under the assumption of harmonic oscillator potential. The levels are corrected for vacuum polarisation. The agreement with experimental values is better than 0·5%. An accurate method of solving the Dirac equation to obtain the energy eigenvalues is outlined. The importance of choosing the ‘classical turning point’ as the radius for matching the interior and exterior solutions is discussed. 相似文献
992.
The motion of a rigid plastic cantilever beam which is surrounded by a damping medium and struck transversely at the tip by a moving mass is studied. The elementary theory, which disregards effects due to rate of straining and geometry changes is used. The governing equations of motion are integrated numerically. For comparison the case of discrete damping provided at the tip only is also solved. Results are presented for a wide range of parameters. 相似文献
993.
Theoretical natural frequencies and mode shapes of the first four coupled modes of a uniform pretwisted cantilever blade and the first five coupled flexural frequencies of pretwisted tapered blading are determined by using the Reissner method. The shape functions for the bending moments and deflections are developed in series form and with these used in the dynamic Reissner functional, the frequency equation is obtained by minimizing it through the Ritz process. A convergence study made in the case of the pretwisted uniform blade indicates that there appears to be a quicker convergence of the natural frequencies and that a five-term solution yields a set of results that are in good agreement with the theoretical and experimental values of other authors, available in the literature. The mode shapes obtained from the present analysis are compared with those from an earlier investigation and the effect of ignoring the shear deflection and rotary inertia in the analysis is discussed. The effects of breadth taper and depth taper on the vibration characteristics of pretwisted cantilever blading are discussed from the results obtained in the present limited study and it is observed that an extensive investigation appears to be necessary to draw positive conclusions covering wide ranges of pretwisted blade parameters. 相似文献
994.
The synthesis of the cis and trans forms of the cyclic dipeptide of O-diazoacetyl-DL-serine is described. 相似文献
995.
It is shown that resonant energy exchange between two gases can alter the absorption of radiation by either, and that hydrocarbons present up to 100 ppm in the atmosphere as pollutants affect its absorption at 10.6 μ. This reduces the initial cooling time reported in the transmission of 10.6 μ laser beams in the atmosphere. 相似文献
996.
A detailed DSC study has been done for the substance HxBPA in the temperature range 170 to 380 K and the scheme of transitions in this compound has been deduced. From X-ray work, values for the smectic layer thickness and inplane intermolecular distance have been found in two of the liquid crystalline phases, P2 and SH. 相似文献
997.
The L1 subshell orbital electron capture probability PL1 in the decay of 33.4 y 207Bi to the 2339.89 keV level in 207Pb is measured to be 0.518 ± 0.081 (95% confidence) by a new method in which L1 subshell characteristic X-rays in the Lγ X-ray peak are observed in an Xγt coincidence mode with 1770.23 keV γ-rays. The value of PL2is 0.047 ± 0.015 (95% confidence). From these results a value of QEC = 39-8+21 keV is obtained for capture transitions to the 2339.89 keV level. The absence of K-capture to this level also is established by absence of K X-rays in coincidence with 1770.23 keV γ-rays. 相似文献
998.
Y.V. Chalapati Rao 《Chemical physics letters》1979,62(1):107-110
SSH—Tanczos calculations are carried out to estimate the energy transfer probabilities and the slow vibrational relaxation time in SO2 in the temperature range 300–2000 K. The theoretical results suggest a series process below 1000 K, and a complex series/parallel process above that temperature for the vibrational relaxation in SO2. The theoretical results are compared with the known experimental data. 相似文献
999.
The highT c superconductor YBa2Cu3O7?x has been found to lose appreciable amount of oxygen in a surprisingly low temperature range (~425–630 K), which drastically degrades the superconducting property. Accompanying this oxygen loss, the resistance behaviour has also been found to change from metallic to semiconducting. 相似文献
1000.