Reconstruction of an acoustically sound-soft obstacle from one incident field and the far-field pattern

The problem considered is that of determining the shape of aplane acoustically sound-soft obstacle from the knowledge ofthe far-field pattern for one time-harmonic incident field.An iterative procedure is proposed based on two boundary integralsrepresenting the incident field and the far-field pattern, respectively.Numerical examples are included which show that the proceduregives accurate numerical approximations in relatively few iterations.     

热效应对光折变晶体两波耦合的特性影响的理论分析

用一种模型对两波耦合进行了分析，导出了强度相位的解析式，对影响两波耦合的参数进行了理论分析。分析了对ＢａＴｉＯ３光折变晶体的两波耦合的测量结果。     

运用严格耦合波理论计算平面电介质光栅的衍射效率

本文阐述了严格耦合波理论的基本思想。针对横电波的情况，详细分析了运用严格耦合波理论实现光栅衍射效率计算的方法，并且进一步给出了编制计算衍射效率程序的步骤。通过一个具体计算实例表明：各衍射级分布的光能量之和等于入射光的能量，满足能量守恒定律，从而证实了计算结果的正确性。     

组合原则回溯

从组合原则产生的背景和关键入手，分析和叙述了里兹的组合原则在光谱学上的重要意义，同时，也阐述了它与玻尔氢原子理论之间的关系。     

冲击波处理的结晶MgO的化学分析正电子谱研究

冲击波处理的结晶ＭｇＯ的化学分析正电子谱研究＊张菊郑小明（杭州大学催化研究所，杭州３１００２８）常志向（抚顺石油化工研究院，抚顺１１３００１）关键词冲击波，化学分析正电子谱，结晶氧化镁，丁烯，脱氢冲击波是在介质中以超音速传播的压力脉冲．气体中的冲击波...     

2-巯基乙醇自组装膜电极对多巴胺电催化氧化及其分析应用

在裸金电极上制备了 2 巯基乙醇自组装膜电极 (ME AuSAMs) ,研究了多巴胺 (DA)在ME AuSAMs上的电化学行为 ,发现该膜电极对DA的氧化具有良好的电催化作用 ,氧化过电位降低了 3 94mV ,测得DA的扩散系数D为 9.1 4 5× 1 0 - 7cm2 s,初步探讨了电催化机理。采用水平衰减全反射 傅里叶变换红外光谱 (ATR FTIR)技术对ME AuSAMs进行了表征 ;方波伏安法 (squarewavevoltammetry ,SWV)测定DA ,其氧化峰电流与DA浓度在 2 .0 0× 1 0 - 6 ～ 1 .0 0× 1 0 - 4 mol L范围内呈线性关系 ;相关系数为 0 .9998,检出限为 4 .0 0× 1 0 - 7mol L。该电极用于DA药物针剂的测定 ,结果满意     

Comparison of localization and delocalization indices obtained with Hartree-Fock and conventional correlated methods: effect of Coulomb correlation

Atomic populations and localization [lambda(A)] and delocalization [delta(A,B)] indices (LIs and DIs) are calculated for a large set of molecules at the Hartree-Fock (HF), MP2, MP4(SDQ), CISD, and QCISD levels with the 6-311++G(2d,2p) basis set. The HF method and the conventional correlation methods [MP2, MP4(SDQ), CISD, and QCISD] yield distinct sets of LIs and DIs. Yet, within the four conventional correlation methods the differences in atomic populations and LIs and DIs are small. Relative to HF, the conventional correlation methods [MP2, MP4(SDQ), CISD, QCISD] yield virtually the same LIs and DIs for molecules with large charge separations while LIs and DIs that differ significantly from the HF values--the LIs are increased and DIs decreased--are obtained for bonds with no or small charge separations. Such is the case in the archetypal homopolar molecules HC(triple bond)CH, H2C=CH2, CH3-CH3, and "protonated cyclopropane" C(3)H(7) (+), in which case the bonding may be atypical. Relative to HF, the typical effect of the conventional correlation methods is to decrease the DI between atoms.