Surface-enhanced Raman scattering study of polymer on metals. III. Chemisorbed polybenzimidazole and its corrosion-inhibiting properties at high temperature

Chemisorption of polybenzimidazole on silver and copper etched with nitric acid has been observed by surface-enhanced Raman scattering (SERS). The polymer is found to react chemically with silver, forming a complexed film on the surface. The SERS spectra show that polybenzimidazole film inhibits oxidation of the metal at high temperature, unlike chemisorbed benzimidazole, benzotriazole, and poly(4-vinyl pyridine). © 1992 John Wiley & Sons, Inc.     

触销式双障碍买权价值过程鞅性

主要证明了在不存在交易成本的完全市场条件下连续时间欧式触销式双障碍买权贴现到0时刻的价值过程为鞅,并且给出了对应单障碍买权价值过程的鞅性质.同时还讨论了执行价格为随机的触销式双障碍买权的鞅性质,给出了任意时刻 t(0≤ t≤T)其内在价值的表达式.     

氢原子的固有电偶极矩

用经典力学和双波量子力学计算了氢原子的固有电偶极矩。双波量子理论算得的结果在经典极限下与经典力学的结果一致。普通量子力学对氢原子Stark效应中表现出来的电偶极矩难以做出很好的解释，因为一个波函数描述的是系综而不是单个粒子。经典力学和双波量子力学可描述单个粒子的行为，对永久电偶极矩的计算和解释显得自然而合理。     

关于"惯性秤"实验的思考

介绍了惯性秤的基本原理，分析了惯性秤不同放置情况的测量结果。     

Rapid syntheses of oligo(p-phenyleneethynylene)s via iterative convergent approach

A general and controlled bidirectional growth strategy enable a very rapid and efficient construction of oligo(phenyleneethynylene)s possessing functional groups such as methylthio and thioacetate groups at both ends. The strategy employs only one reaction type with good to moderate yields to grow the conjugated chains. The synthesis is efficient and can give 23 benzene rings and 22 carbon-carbon triple bonds in the conjugated chains. The compounds are fully characterized by ¹H and ¹³C NMR and UV/vis and fluorescence spectroscopy.     

Hybrid inorganic/organic interpenetrating polymer networks based on zeolite 13x and polystyrene

A hybrid inorganic/organic interpenetrating polymer network (IPN) of a three-dimensional network structure zeolite crystal (13X, powder) and crosslinked or linear polystyrene (PS) was prepared and characterized by differential scanning calorimetry (DSC), solid-state¹³C-NMR, and scanning electron microscopy (SEM). The size and shape of the crystalline zeolite particles were revealed on SEM micrographs in both the pure zeolite and the IPNs. Solubility tests and the results of DSC with solid-state ¹³C-NMR confirm that some organic PS chains are incorporated within the internal three-dimensional channels of the zeolite particles. We speculate that the internal PS chains may adopt an extended “one-dimensional” conformation and exhibit no bulk polymer glass transition. These novel hybrid inorganic/organic IPNs are a new kind of IPN structure. © 1995 John Wiley & Sons, Inc.     

两个图的积的S-不可收缩性(英)

本文从组合角度明确给出了两个图的积是S-不可收缩的特征．     

A globally convergent algorithm for the Euclidean multiplicity location problem

The Euclidean single facility location problem (ESFL) and the Euclidean multiplicity location problem (EMFL) are two special nonsmooth convex programming problems which have attracted a large literature. For the ESFL problem, there are algorithms which converge both globally and quadratically. For the EMFL problem, there are some quadratically convergent algorithms, but for global convergence, they all need nontrivial assumptions on the problem.In this paper, we present an algorithm for EMFL. With no assumption on the problem, it is proved that from any initial point, this algorithm generates a sequence of points which converges to the closed convex set of optimal solutions of EMFL.This research is supported in part by the Air Force Office of Scientific Research Grant AFOSR-87-0127, the National Science Foundation Grant DCR-8420935 and University of Minnesota Graduate School Doctoral Dissertation Fellowship awarded to G.L. Xue.     

A global optimization design for quasi-optics power combiner of 3mm wave solid-state sources

This paper describes a global optimization design for quasi-optics power combiner of solid-state millimeter-wave sources. The operating frequency is about 100 GHz and the oscillating sources are GaAs Gunn diodes. The source-array plane is a matrix consisting of NxN (N=3,5, ..., 2k+1, where k is positive integer) diodes. The radio frequency power of the combiner is from threefold to sevenfold larger than the sum total of the single diodes power. The global optimums of the array and the location in the cuvity of the suorce-array plane will be given by a global optimizition method.     

利用KTP晶体实现1.08μmNd：YAP激光器锁模

本文描述了利用ＫＴＰ晶体和腔的基波输出镜构成非线性镜实现１．０８μｍＮｄ：ＹＡＰ激光器的被动锁模。实验表明，这种新的锁模技术比用染料作可饱和吸收体的被动锁模技术有很多突出的优点，具有很大的发展潜力。实验测得锁模时基波１．０８μｍ输出２．４ｍＪ，二次谐波０．５４μｍ输出０．５ｍＪ（同样条件下的静态输出为２．５ｍＪ），基波脉冲的平均脉宽为４０ｐｓ。