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841.
In a magnetic field, Cs2 molecules were excited from the ground X1Σ+g(vX=0,JX=55) level to the D 1Σ+u(v=46,J=54) level by dissociation laser light linearly polarized parallel to the field, for which the magnetic sublevels were degenerated and thus all the transitions between them were simultaneously stimulated. Probe laser light excited the dissociated Cs 6p2P3/2 atomic fragments to 6p2D3/2 level and the resultant 6p2P1/2 - 6d2D3/2 emission was detected as the function of the wavelength of the probe light. The populations of the 6p2P3/2,mj magnetic sublevels were determined from the relative strengths of the 6p2P3/2,mj - 6d2D3/2,m'j transitions induced by the probe light. Non-zero orientation O0 was found in the ensemble of dissociated Cs 6p2P3/2 atomic fragments. The orientation O0 increased as the magnetic field strength increased. It was demonstrated both experimentally and theoretically that the orientation O0 was induced through the interference in the excitation and dissociation paths in the presence of an external magnetic field, even when all degenerated transitions between the magnetic sublevels of the molecules are simultaneously excited by the light linearly polarized parallel to the field.  相似文献   
842.
  Tianquan  Liu  Zhiguo  Zheng  Zhiren  Huang  Jian  Su  Wenhui 《Optical and Quantum Electronics》2004,36(4):389-397
Based on the dynamic equations of an electro-optic bistable system with delay in its feedback loop, we theoretically investigate second-order effects of the output resonance and frequency-locking of the system.  相似文献   
843.
The latest results from the Wilkinson Microwave Anisotropy Probe (WMAP) with regard to the Cosmic Microwave Background (CMB) throw up some intriguing results, and the question has been asked “Does this point to new physics?” We point out that indeed all this indicates new physics on the Planck scale.  相似文献   
844.
High-precision mass measurements on lithium-like and hydrogen-like 40Ca-ions are reported. The obtained mass of the hydrogen-like and lithium-like ion is 39.952181819(29) u and 39.953272223(24) u, respectively. The corresponding mass of the 40Ca atom is 39.962590858(22) u. This new value has a precision ten times higher than the literature value.  相似文献   
845.
王政 《应用数学》2005,18(1):119-127
本文在连续时间场合研究回归函数的非参数估计量之一———局部光滑统计量的性质 .不仅给出其a.s.收敛的一个速度 ,而且证明了该统计量不受边界效应影响的优良性质 ;同时指出了在连续时间的场合 ,估计量中窗宽的选择和样本的轨道性质都对该估计量的性质产生重要的影响  相似文献   
846.
In this paper, we report on the sharp peak observed in the third harmonic voltage response generated by a bias sinusoidal current applied to several strips patterned in a YBa2Cu3O 7 - δ thin film and in two La2-xSrxCuO4 thin films, when the temperature is close to the normal-superconductor transition. The lambda-shaped temperature dependence of the third harmonic signal on the current characteristics is studied. Several physical mechanisms of third harmonic generation are examined. Received 13 November 2002 / Received in final form 21 February 2003 Published online 7 May 2003  相似文献   
847.
The electron polarizabilities (α0·1024/cm3 molec.−1) were estimated from the data on refractive indices and molar volumes of H/D isotopomers of methanol at 25 °C using the Lorentz-Lorentz formula: 3.265 (CH3OH), 3.260 (CH3OD), 3.235 (CD3OH), and 3.231 (CD3OD). A relationship between the isotope effects for α0 and volume (packing) changes in the structure of liquid methanol induced by deuterosubstitution in the methanol molecule was proposed. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1927–1928, August, 2005.  相似文献   
848.
This paper deals with the solution of nonlinear programming problems arising from elliptic control problems by an interior point scheme. At each step of the scheme, we have to solve a large scale symmetric and indefinite system; inner iterative solvers, with an adaptive stopping rule, can be used in order to avoid unnecessary inner iterations, especially when the current outer iterate is far from the solution. In this work, we analyse the method of multipliers and the preconditioned conjugate gradient method as inner solvers for interior point schemes. We discuss the convergence of the whole approach, the implementation details and report the results of numerical experimentation on a set of large scale test problems arising from the discretization of elliptic control problems. A comparison with other interior point codes is also reported. This research was supported by the Italian Ministry for Education, University and Research (MIUR) projects: FIRB Project: “Parallel Nonlinear Numerical Optimization PN 2 O” (grant n. RBAU01JYPN, ) and COFIN/PRIN04 Project “Numerical Methods and Mathematical Software for Applications” (grant n. 2004012559, ).  相似文献   
849.
基于Druce等人的方法,提出了一种新的g玻色子效应重整化微扰论方法.对使用此两种方法的前提条件一弱耦合条件,作了考察,并给出了满足前提条件下,两种方法的g玻色子效应的重整化计算结果.对比分析表明,提出的方法克服了Druce等人方法的局限性,对g玻色子效应的考虑更充分.  相似文献   
850.
Summary A search has been made on the charge-changing partial cross-sections by using 0.927 GeV/n238U ion from LBL BEVALAC projected at an angle 30° on27Al target and CR-39 (DOP) was used as analyser. The irradiated plastic sheets were duly etched for one hour in 6.25N NaOH solution and about 1680 cone lengths at both the surfaces of the CR-39 (DOP) sheets were optically measured. The cone length distribution exhibits the existence of U fragments in the charge range 84≤Z≤91 and the estimated partial cross-sections range from 60 to 400 mb. The present data are in accord with the fit to the extrapolated data of Binnset al.  相似文献   
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