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81.
通过电位-时间曲线的特征,研究了化学镀镍反应初期不同基体材料的催化特征.在同质基体上可以瞬间诱发化学镀反应,而在异质基体上的诱导期因镀液组成不同而发生变化.在异质基体材料中,Pt无催化活性,Pd的诱发时间最长. 相似文献
82.
83.
A new probabilistic cellular automaton model is introduced to simulate cluster and interface growth in two dimensions. The dynamics of this model is an extension to higher dimensions of the compact directed percolation studied by Essam. Numerical results indicate that the two-dimensional cluster coarsening and growth can be described only approximately by the conventional cluster size scaling due to a crossover in the growth mode. The spreading of the initially flat interface follows a purely diffusional,t
1/2, law. 相似文献
84.
本文介绍非线性方程转化直线性方程和多元线性回归法来分析近代物理实验中塞曼效应分裂干涉圆环多处选点测量的处理过程。 相似文献
85.
H. Barentzen 《Annalen der Physik》2006,15(9):684-698
The eigenvalues of the weakly coupled T ? t Jahn‐Teller problem are known for several decades, and the same holds also true for the eigenstates. These, however, are only given in the traditional position representation, which proves inconvenient if one attempts to extend the weak‐coupling treatment into the region of stronger coupling. Here the solution of the T ? t eigenvalue problem at weak coupling is derived in terms of creation and annihilation operators. This reformulation of the problem is nontrivial, since the algebraic form of the oscillator eigenvectors, being simultaneous angular‐momentum eigenstates, has been worked out only recently and is probably still widely unknown. The electronic and oscillator eigenstates are then coupled to form eigenvectors of the total angular momentum. Finally, in preparation for an extension of the weak‐coupling treatment, the action of the boson creation and annihilation operators on the oscillator eigenvectors is calculated, thus completing the algebraic approach to the weakly coupled T ? t system. 相似文献
86.
Dieter Petrak 《Particle & Particle Systems Characterization》2002,19(6):391-400
The objective of this study was to compare the measuring results of a fiber‐optical probe based on a modified spatial filtering technique with given size distributions of different test powders and also with particle velocity values of laser Doppler measurements. Fiber‐optical spatial filtering velocimetry was modified by fiber‐optical spot scanning in order to determine simultaneously the size and the velocity of particles. The fiber‐optical probe system can be used as an in‐line measuring device for sizing of particles in different technical applications. Spherical test particles were narrow‐sized glass beads in the range 30–100 μm and irregularly shaped test particles were limestone particles in the range 10–600 μm. Particles were dispersed by a brush disperser and the measurements were carried out at a fixed position in a free particle‐laden air stream. Owing to the measurement of chord lengths and to the influence of diffraction and divergent angle, the probe results show differences from the given test particle sizes. Owing to the particle‐probe collisions, the mean velocity determined by the probe is smaller than the laser Doppler mean velocity. 相似文献
87.
Kiyoshi Kurosawa 《Optical Review》1997,4(1):A38-A44
This paper describes development of the optical current transducers using flint glass fiber as the Faraday effect sensing
element. Excellent polarization properties of the fiber with low birefringence are described, and the design and test data
of a current transducer using the fiber manufactured for use in electric power facilities are reviewed. Experimental results
on flexible characteristics of a scheme with round trip light transmission in the fiber is also reported. 相似文献
88.
Orthogonally linear polarized lasers(Ⅰ)--principle and devices 总被引:1,自引:0,他引:1
Two kinds of orthogonally polarized lasers, i.e. Zeeman dual-frequency lasers and four-frequency ring lasers (laser gyros) have been developed since the invention of lasers, in which circularly polarized lights oscillate. This paper summarizes recent progress of the study on orthogonally linear polarized lasers with the standing wave cavity. Firstly, the expression of producing orthogonally linear polarized lights in standing wave cavity, i.e. laser frequency splitting, is given. Almost all the birefringence effects made in laser cavity are used to produce orthogonally linear polarized lights. The effect includes quartz crystal birefringence effect, calcite birefringence effect,stress (photo-elastic) birefringence effect and electro-optical birefringence effect. Secondly, several physical phenomena of orthogonally linear polarized lasers are discovered such as aberrance of frequency splitting curves caused by optical activity of quartz crystal, order-passing of longitudinal modes with frequency splitting and strong modes competition. Finally, because the traditional Zeeman dual frequency laser cannot output frequency difference larger than 3 MHz, the approaches of obtaining larger frequency difference are studied. The sequential results, several kinds of orthogonally polarized lasers, are described, such as birefringence dual frequency lasers outputting a frequency difference from 40 MHz to hundreds of megahertz, birefringence-Zeeman dual frequency lasers outputting a frequency difference from 1 MHz to hundreds of megahertz, the LD pumped YAG birefringence dual frequency laser outputting frequency difference of several gigahertz, and the lasers whose longitudinal mode spacing is c/4L instead of c/2L. 相似文献
89.
用解析法对双势阱分子的自发隧道效应进行了研究,得到了粒子的自发隧道效应周期与能级裂距成反比关系,从而对隧道效应对双势阱分子激发态的稳定性贡献给予了积极的肯定. 相似文献
90.
Mössbauer spectroscopy was used to investigate the influence of dissolved hydrogen on the interatomic bonds in austenitic steels. It was carried out to prove the decohesion mechanism of hydrogen embrittlement (HE). It is shown that hydrogen increases Debye temperature, i.e., the interatomic bonds in hydrogenated austenitic steel becomes stronger. 相似文献