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991.
We solve the atom-field interaction model including the Kerr effect, Stark effect and Doppler effect exactly within a unified approach. The detuning in the effective Hamiltonian depends on two conserved operators of the system. Finally, the influence of atomic mass center motion on the antibunching effect of photons is discussed. 相似文献
992.
993.
John F. Smalley Marshall D. Newton Stephen W. Feldberg 《Electrochemistry communications》2000,2(12):832-838
Theoretical relationships are developed to describe the open-circuit responses associated with the indirect laser-induced temperature-jump (ILIT) method, a method for measuring fast electron-transfer rate constants of surface-attached redox species. The analysis is also applicable to data obtained using the coulostatic charge-injection method. The unique relationship between km, the relaxation rate constant for the ILIT (or coulostatic) response, and Ei, the potential at which the system is initially poised, exhibits a surprising sensitivity to the values of k0, Ei0′ (the standard rate constant and formal potential for the redox couple), α (the transfer coefficient in the Butler–Volmer equation) and γ (a dimensionless parameter which is directly proportional to the total surface concentration of the redox moiety). ILIT data for several examples of surface-attached ferrocene moieties confirm the theoretically predicted km vs Ei behavior. Values of Ei0′ and γ extracted from the ILIT data agree well with the values obtained from cyclic voltammetric data thereby confirming that the ILIT and cyclic voltammogram (CV) experiments are sampling the same ferrocene population. 相似文献
994.
C. Goutaudier F. S. Ermeneux M. T. Cohen-Adad R. Moncorge 《Journal of Crystal Growth》2000,210(4):693-698
High-quality and crack-free Y2O3 single crystals containing low concentrations of Tm3+, Tb3+ and Yb3+ were obtained. The crystals were grown in the form of monocrystalline fibers by using a floating zone method with laser heating (laser-heated pedestal growth). 相似文献
995.
富勒烯的固体薄膜一般分为气相沉积膜、液相沉积膜、LB(Langmuir Blodgett)膜和化学自组装膜.化学自组装膜是通过特定的化学反应,将富勒烯通过化学键固定于基片上而形成的膜. 相似文献
996.
NovelHighlyBranchedPolyesterNanoparticles(I)──Light-ScatteringCharacterizationMARong-Jiu(PolymerInstitute,JilinUniversity,Cha... 相似文献
997.
The trace element Zn in the Zn-doped multi-layer ш - V group compound semiconductor was detected by means of Resonant Laser Ablation/lomzation(RLA). A detection limit of 2. 5 X 1017 atoms/cm3 (about 5 ppm) has been estimated. The mass spectra and the optical resonant ionization spectrum around 214 nm are given in this paper. 相似文献
998.
应用PADE'逼近方法构造出高阶格式,对一类简单方程组,该方法可导出一种快速递推算法,它能满足这类简单方程自身存在的守恒要求。 相似文献
999.
利用光学多普勒效应和外差方法搭建了一台光纤位移干涉仪。装置采用光通信行业中已经发展成熟的器件,主要由带尾纤的半导体激光器、三端口环形器、光纤探头、宽带探测器以及宽带高采样率示波器等构成。整个装置结构简单,价格便宜,采用了信号光和参考光同轴结构,实现了任意反射面的速度测量,克服了偏振模式色散的影响,能够实现长量程测量,量程达到20 mm。利用该装置进行了爆轰加载下飞片速度测量,测量最高速度达到1 300 m/s,工作距离达到20 mm,同时利用VISAR对飞片速度进行了对比测量,结果表明用两种不同方法所测得的速度曲线吻合很好。 相似文献
1000.
D. Sofikitis ;A. Fioretti ;S. Weber ;M. Viteau ;A. Chotia ;R. Horchani ;M. Allegrini ;B. Chatel ;D. Comparat ;P. Pillet 《化学物理学报(中文版)》2009,22(2):149-156
The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample of cold molecules, initially distributed over several vibrational levels, has thus been transfered into a single selected vibrational level of the singlet X^1∑g ground electronic state. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but limited in its frequency bandwidth with a spatial light modulator. In such a way we are able to eliminate transitions from the selected level, in which molecules accumulate. In this paper we briefly report the main experimental results and then address, in a detailed way by computer simulations, the perspectives for a "complete" cooling of the molecules, including also the rotational degree of freedom. Since the pumping process strongly depends on the relative shape of the ground and excited potential curves, ro-vibrational cooling through different excited states is theoretically compared. 相似文献