Propagation properties of off-axis Hermite-cosh-Gaussian beam combinations through a first-order optical system

Based on the Collins integral formula, the analytic expressions of propagation of the coherent and the incoherent off-axis Hermite-cosh-Gaussian (HChG) beam combinations with rectangular symmetry passing through a paraxial first-order optical system are derived, and corresponding numerical examples are given and analysed. The resulting beam quality is discussed in terms of power in the bucket (PIB). The study suggests that the resulting beam cannot keep the initial intensity shape during the propagation and the beam quality for coherent mode is not always better than that for incoherent mode. Reviewing the numerical simulations of Gaussian, Hermite-Gaussian (HG) and cosh Gaussian (ChG) beam combinations indicates that the Hermite polynomial exerts a chief influence on the irradiance profile of composite beam and far field power concentration.

基于一阶迁移系统的限界模型检测工具实现

基于布尔可满足性(SAT)的限界模型检测是一种高效的模型检测方法，它具有快速查错，反例最小化等特点，已经成为学术界和工业界关注的热点。近些年出现了很多集成限界模型检测算法的验证工具，如ITC-IRST、卡内基梅隆大学(CMU)等多家科研机构联合开发的NuSMV工具；加利福尼亚大学伯克莱分校(UC Berkeley)、科罗拉多大学博尔德分校(CU Boulder)联合开发的VIS工具等。因此目前对于限界模型检测方法的研究和相关工具的设计与开发具有重要而广泛的意义。在进行限界模型检测的建模过程中，不同的工具采用了自定义的建模语言。如经典工具SPIN采用的建模语言是Promela语言，NuSMV采用的是自定义的NuSMV语言。随着系统验证规模的不断增大，建模语言的特点将会直接影响到建模的效率。例如采用NuSMV语言去建立一个网络通信协议模型会显得比较复杂和耗时，应用NuSMV语言去描述一个简单的数据链路层网络协议ABP协议(Alternating Bit Protocol)就不如采用Promela语言去描述显得直观和自然。 为了简化在限界模型检测过程中模型的建立过程，本文给出了一种采用基于一阶迁移系统语言描述的模型建立方法，并在一阶迁移系统语言中实现了通道的功能，从而增强了描述能力。在此基础上完成了一个以基于插值和k步归纳限界验证算法为核心的模型检测工具(BMCF)。最后利用该工具对常见的互斥协议，简单数据传输协议的性质进行了分析与验证。结果表明，利用该工具对系统进行建模具有方便直观的特点，并借助实现的验证算法能高效的检验安全性质的正确性，如果性质不成立工具会给出反例提示。

基于一阶迁移系统的限界模型检测工具实现

为了简化在限界模型检测过程中模型的建立过程,给出了一种采用基于一阶迁移系统语言的模型建立方法,并在此一阶迁移系统语言中加入了通道的功能,增强了描述能力。然后在此基础上完成了一个以基于插值和k步归纳的限界验证算法为核心的模型检测工具(BMCF),最后利用该工具对常见的互斥协议,简单数据传输协议的性质进行了分析与验证。结果表明,利用该工具对系统进行建模具有方便直观的特点,并借助实现的验证算法能高效的检验性质的正确性,如果性质不成立工具还会给出反例提示。

Effect of crystal-disrupting chlorohydroquinone on the first-order transitions of poly(aryl ether ketone)s containing biphenyl units

The novel poly(aryl ether ketone)s were synthesized by nucleophilic substitution reactions of 4,4'-difluorobenzophenone with 4,4'-biphenyldiol and chlorohydroquinone. As expected, the copolymers have lower melting transitions than the biphenyldiol-based homopoly(aryl ether ketone) because of the copolymerization effect of the crystal-disrupting monomer chlorohydroquinone. Copolymers containing 50 and 70% biphenyldiol show two first-order transitions which are associated with the crystal-to-liquid crystal transition and the liquid crystal-to-isotropic transition.

THE APPLICATION OF ULTRAMICROELECTRODE IN HOMOGENEOUS CATALYTIC REACTION .5. ELECTROCHEMICAL-BEHAVIOR OF MACRO-MICRO-MACRO TRIPLE AND MICRO-MICRO TWIN ELECTRODES AND THE QUASI-FIRST-ORDER HOMOGENEOUS CATALYTIC REACTION (EC') AT GENERATION/COLLECTION ELECT

A new type of macro-micro-macro triple electrode has been fabricated, the steady-state currents of solution redox species have been observed at an ultramicroband electrode by linear potential scan voltammetry, and generation/collection experiments have al

Thermomagnetic behavior and first order magnetization processes of Sm3Fe29-xTx and Sm3Fe29-xTxN4 (T = V and Cr)

A systematic investigation of structure and intrinsic magnetic properties of the compounds Sm3Fe29-xTx (T = V and Cr) and their nitrides has been performed. Nitrogenation resulted in remarkable improvements in the saturation magnetization and anisotropy fields at 4.2 K and room temperature. First order magnetization processes are observed at around 5.7 T for Sm3Fe26.7V2.3 and around 2.8 T for Sm3Fe24.0Cr5.0 and Sm3Fe24.0Cr5.0N4, respectively. The spin reorientation of the easy magnetization direction of Sm3Fe26.7V2.3 is observed at around 230 K. As a preliminary result, the maximum remanence B-r of 0.94 T, the coercivity mu(0)H(C) of 0.75 T, and the maximum energy product (BH) of 108.5 kJ/m(3) for the nitride magnet Sm3Fe26.7V2.3N4 are achieved by ball-milling at 293 K.

Absorbance kinetics of dye-doped systems with photochemical first order kinetics

Often it is assumed that absorbance decays in photochromic materials with the time dependence of the photochemical kinetics, i.e. exponentially for first order kinetics. Although this may hold in the limiting case of vanishing absorbance, deviations are to be expected for realistic samples, because the local photochemical kinetics slows down with increasing initial absorption and penetration depth of the radiation. We discuss the theory of the kinetics of initially homogeneous photochromic samples and derive analytical solutions. In extension of Tomlinson's theory we find an analytical solution that holds with good approximation even for samples that exhibit a small residual absorption in the saturation limit. The theoretical time dependence of the absorbance originating from photochemical first order kinetics of dye-doped systems is compared with experimental data published by Lafond et al. for fulgides doped in different polymer matrices. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Order-Order Transition of C -> sdG -> sL -> S in ABC Triblock Copolymer Thin Film Induced by Solvent Vapor

The morphology transition of polystyrene-block-poly(butadiene)-block-poly(2-vinylpyridine) (SBV) triblock thin film induced in benzene vapor showing weak selectivity for PS is investigated. The order-order transitions (OOT) in the sequence of core-shell cylinders (C), sphere in 'diblock gyroid' (sdG), sphere in lamella (sL) and sphere (S) are observed. The projection along (111) direction in Gyroid phase (sdG(111)) is found to epitaxially grow from C(001) in the film.