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71.
Based on the extended Huygens-Fresnel integral formula, analytical formulae for the elements of cross-spectral density matrix of partially polarized electromagnetic twist anisotropic Gaussian Schell-model (TAGSM) beam propagating in turbulent atmosphere can been derived by a tensor method. Our main attention was focus on the effect of the atmospheric turbulence, twist parameters and partial coherence on the spectral degree of polarization, the spectral degree of coherence and the spectral density. Numerical calculation results and analysis are given. 相似文献
72.
Melanie Schnell Dr. Gerard Meijer Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(33):6010-6031
Research with cold molecules has developed rapidly in recent years. There is now a variety of established methods for cooling molecules into the millikelvin range. Nevertheless, a focal point of current research is directed toward finding new ways to bring the temperature of molecules even closer to absolute zero. Samples of cold molecules offer not only important applications for high‐resolution spectroscopy, which benefit from the increased interaction time of slow molecules with electromagnetic radiation; they also promise access to an exotic regime of chemical reactivity, in which phenomena such as quantum tunneling and quantum resonances predominate. This review begins with an introduction to the methods by which cold molecules can be prepared, with special emphasis on Stark deceleration and traps. In addition to applications of cold molecules that have already been partially achieved, an important focus of the review concentrates on possible future applications, and both aspects are illustrated with selected examples. 相似文献
73.
74.
Using the Riesz basis approach, we study a sandwich beam that is composed of an outer stiff layer and a compliant middle layer.
The dynamic behavior and analyticity of the system are obtained based on a detailed spectral analysis and Riesz basis generation.
As a consequence, the analyticity of the solution and the exponential stability of the system are concluded.
This work was supported by the National Natural Science Foundation of China, Program for New Century Excellent Talents in
the Universities of China and by the National Research Foundation of South Africa. 相似文献
75.
V. N. Il'in 《Journal of Applied Spectroscopy》1999,66(6):971-975
An interference method for controlling the refractive index of liquids pumped through a capillary is considered. The liquid
is sounded by two systems of interference bands, the period of which differs by an insignificant value prescribed by the condition
of nonius coincidence. An analytical expression is obtained to calculate the refractive index of the liquid controlled in
automatic reading of the interference patterns.
Institute of Electronics, National Academy of Sciences of Belarus, 22 Logoiskii Trakt, Minsk, 220841, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 832–835, November–December, 1999. 相似文献
76.
77.
X.-M. Su Z.-C. Zhuo Z.-H. Kang L.-J. Wang J.-Y. Gao 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,17(3):395-398
We investigate the conditions in which the propagation of an electromagnetic wave is changed from transparency to cutoff in
a non-uniform plasma. The allowed frequency range of the driving wave is obtained for the case that the probe frequency is
above the plasma frequency. The effect of the power of the driving field on the range is analyzed.
Received 23 May 2001 相似文献
78.
Akira Ozawa 《Pramana》2001,57(2-3):525-533
Recent experimental programs at RIKEN concerning RI beams are reviewed. RIKEN has the ring cyclotron (RRC) with high intense
heavy-ion beams and large acceptance fragment separator, RIPS. The complex can provide high intense RI-beams. By using the
high intense RI-beams, a variety of experiments have been done. Recently, nuclear structure for unstable nuclei has been paid
much attention. In special, disappearance and appearance of magic numbers are discussed experimentally and theoretically.
Thus, in this review, related experiments concerning disappearance and appearance of magic numbers are described. Finally,
future project in RIKEN, RI-beam factory. is introduced briefly. 相似文献
79.
80.
This paper deals with a new solution technique for approximately solving certain variational problems in elasticity by using discrete optimization techniques that were originally used in information theory. This allows us to easily and approximately solve large deformation buckling problems for slender cantilever beams (including post-buckling behavior) as well as problems where the strain energy function is non-convex.The core idea is to quantize or discretize the variables describing the possible configurations of the body. This, when combined with the fact that the variational problem has an inherent Markov structure allows us to use computationally efficient search techniques based on dynamic programming (equivalent to finding the shortest path in a weighted directed graph) to find optimal solutions within the quantized state space. The results can be used in two ways: (1) directly as a fast approximate solution to the variational problem (2) As a means for finding very good (nearly minimum energy) initial configurations for application of conventional minimization techniques, which might otherwise fail because of a poor starting configurations which are far from the global minimum. We demonstrate both these uses in the paper. 相似文献