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11.
Mari Grobbelaar‐Van Dalsen 《Mathematical Methods in the Applied Sciences》2004,27(11):1301-1315
This paper is concerned with well‐posedness results for a mathematical model for the transversal vibrations of a two‐dimensional hybrid elastic structure consisting of a rectangular Reissner–Mindlin plate with a Timoshenko beam attached to its free edge. The model incorporates linear dynamic feedback controls along the interface between the plate and the beam. Classical semigroup methods are employed to show the unique solvability of the coupled initial‐boundary‐value problem. We also show that the energy associated with the system exhibits the property of strong stability. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
12.
A crystalline quartz plate of thickness 1.070 mm is calibrated between 370 and 794 nm. Throughout this spectral interval, the retardance varied by 32π and the plate introduced quarterwave retardance 16 times at different wavelengths. The birefringence (ne−no) of crystalline quartz was calculated as a single quantity and varied from 0.00971 at 370 nm to 0.00891 at 794 nm. All measurements were carried out at 23°C. 相似文献
13.
An assignment of the near-infrared bands in the 600–800 nm spectral region observed in magnetic circular dichroism (MCD)
spectra of high-spin ferrous haemoproteins is presented. The assignment is based on a relative energy level scheme for iron
d-electrons, a comparison of predicted and measured temperature dependences of MCD intensity, a sign of MCD bands and a group
theoretical analysis of allowed transitions. The proposed assignment is consistent with the ∼15-nm red shift of the ∼760 nm
band on breakage of the Fe-His bond in deoxy-myoglobin at low pH, with low-temperature photolysis experiments available for
CO complexes of several haemoproteins. In accordance with the observations, the intensity of the MCD bands for proteins with
a sulphur anion of cysteine as proximal haemligand (cytochrome P450 and chloroperoxidase) is predicted to be diminished by
at least one order of magnitude compared to that for proteins with an imidazole of a histidine as a protein-derived haemligand
(i.e. myoglobin, haemoglobin and horseradish peroxidase).
Received: 4 February 1997 / Accepted: 1 May 1997 相似文献
14.
Multinomial permutations on a circle are considered in the framework of combinatorics. Different cases are presented and shown to agree with previously derived formula for the number of cyclic necklaces. Two applied examples are discussed with a view to illustrate the implications of derived formulas. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
15.
等腰三角形Mindlin板的自由振动分析 总被引:2,自引:0,他引:2
提出了一种新方法来对基于 Mindlin剪切变形理论的等腰三角形板进行自由振动分析 .此方法采用了一种新的基函数并利用 pb-2 Rayleigh-Ritz边界函数得到了一种新型的 Ritz方法 .这种方法的有效性通过收敛性和对比性分析得到了证实 .数值结果表明此方法相当精确有效 . 相似文献
16.
17.
关于非平行板电容器电容计算的讨论 总被引:4,自引:3,他引:1
用串联方法计算非平行板电容器的电容,简便地得到与其他方法相同的结果。 相似文献
18.
19.
Takayuki Sakaguchi 《Optical Review》2003,10(3):136-139
We have succeeded in the operation of rotating a fine particle which was held without mechanical contact by circularly polarized laser beams with opposite propagation directions. A polystyrene latex particle 11.9 μm in diameter deformed in a disk-like shape was dispersed in water, and was trapped using the anti-parallel collinear laser beams which were set up so that they had the circular polarization rotating in the same direction. It was observed that the trapped particle rotated in the same direction as the rotation of the circular polarization of light. Inversion of the rotational direction of the circular polarization of light reversed the direction of the rotation of the particle. Although the rotational speed of a particle varied significantly from particle to particle, it was found to be proportional to the laser beam intensity. A typical value for the rotational speed per beam intensity was 2.1 Hz/W. 相似文献
20.
T. I. Khabakhpasheva 《Fluid Dynamics》2003,38(4):592-600
The problem of surface wave diffraction on a floating elastic plate is considered. The relation between the parameters of the elastic vibrations of the plate and the transmitted and reflected wave amplitudes is investigated. It is shown that the maximum amplitudes of the plate stresses and deflections depend nonmonotonically on the incident wave frequency and are reached simultaneously with the maxima of both the transmission coefficient and the length of the wave penetrating into the plate. This makes it possible to use the transmission coefficient as a parameter for investigating the maximum and minimum amplitudes of the hydroelastic vibrations of the plate. As an example, this criterion is used to minimize the vibrations of a plate whose leading edge is elastically connected to the bottom. 相似文献