Ca2+和Pb2+与双层类脂膜相互作用的研究

用电化学方法研究了卵磷脂和氧化胆固醇构成的双层类脂膜与 Ca~(2+)和 Pb~(2+)的相互作用。结果发现:双层类脂膜与含 Ca~(2+)或 Pb~(2+)的溶液接触15分钟后,产生较稳定的膜电位信号并与溶液中 Ca~(2+),Pb~(2+)浓度相关。其作用机制主要是源于静电作用与合作效应,同时,对三种不同存在状态的双层类脂膜的通透性进行了验证,对某些干扰离子和 pH 值的影响进行了研究。     

Book Reviews

Book review in this Article Margaret Dale & Paul Iles (1992) Assessing Management Skills: A Guide to Competencies and Evaluation Techniques Dean Tjosvold (1991) Team Organization: An Enduring Competitive Advantage Brian Thomas (1992) Total Quality Training: The Quality Culture and Quality Training Michael J. Comer, Patrick M. Ardis, & David Price (1992) Bad Lies in Business, McGraw Hill Rosemary Dinnage (1992) The Ruffian on the Stair Peter Frost and Ralph Stablein (Eds) (1992) Doing Exemplary Research Janet Sayers (1992) Mothering Psychoanalysis, Penguin Books Vivian Walsh, Robin Roy, Margaret Bruce & Stephen Potter (1992) Winning by Design: Technology, Product Design & International Competitiveness David Megginson & Mike Pedler (1992) Self-Development: A Facilitators Guide Linda L. Putnam and Michael E. Roloff (1992) Communication and Negotiation Peter M. Senge (1990) The Fifth Discipline: The Art and Practice of The Learning Organization Keith Bradley (1992) Phone Wars, The Story of Mercury Communications Gordon J. Pearson (1992) The Competitive Organization Sonja A. Sackmann (1991) Cultural Knowledge in Organisations: Exploring the Collective Mind     

三唑并嘧啶磺酰胺类除草剂的QSAR研究（II）

三唑并嘧啶类除草剂是作用于乙酰乳酸合成酶的新一类超高效除草剂，本文采用ＣＡＳＡＣ软件中的逐步线性回归方法，在二维水平上通过讨论三唑并嘧啶类化合物对油菜ｒａｐｅ（Ｇｏｓｓｙｐｉｕｍｓｐｐ．）欧龙牙草ｃｏｃｋｌｅｂｕｒ（Ｘａｎｔｈｉｕｍ，ｓｐｐ．）曼陀罗ｊｉｍｓｏｎｗｅｅｄ（Ｄａｔｕｒａ，ｓｔｒａｍｏｎｉｕｍ），牵牛花ａｎｎｕａｌｍｏｒｎｉｎｇｇｌｏｒｙ（ｌｐｏｍｏｅａｓｐｐ。）苋菜ｐｉｇｗｅｅｄ（Ａ     

纳米分辨近场光学显微成象技术现状

介绍了纳米分辨近场光学显微成象技术现状,近场光学显微成象技术大体可分为小孔扫描近场光学显微镜（Ａ－ＳＮＯＭ）、无孔径用射扫描近光学显微镜（Ｓ－ＳＮＯＭ）和光子扫描隧道显微镜（ＰＳＴＭ）三种基本类型,除介绍这三类近场光学显微镜简要成象原理、现状和各自特点外,还重点介绍了大连理工大学纳米成象技术研究组ＰＳＴＭ的研究进展,即ＰＳＴＭ消假象数值模拟和实验研究结果,其实验空间分辨首次达到２．８ｎｍ线扩展函数     

对偶关系与不确定系统的状态估计

本文讨论如下系统状态估计问题, x=A(t)x+B1(t)u(t)+B2(t)w y=C(t)X+D1(t)u(t)+D2(t)w 其中u(t)为已知输入向量,w为不确定向量.假定w为时间t 的函数,对它只知道其可能的变化范围,不知道其具体实现.问题是根据量测y(t),0tT,如何去估计状态变量 x(T)?我们用[1]中所建立的对偶关系式解决了状态的min-max估计问题.在二次型限制之下的min-max状态估计与卡尔曼滤波完全一致.这里所用的方法比起[4]中的方法简单得多.     

Cooperative path planning with priority target assignment and collision avoidance guidance for rescue unmanned surface vehicles in a complex ocean environment

In this paper, a novel cooperative path planning scheme of unmanned surface vehicles (USVs) for rescuing targets in a complex ocean environment is proposed. The primary objective of the rescue USVs is to bring all targets back safely on the premise of first rescuing priority targets, while optimizing the path length, the navigation time and the angular energy. The main contributions of this paper are as follows: (1) The proposed K-means-division (KMD) algorithm is able to identify a complex ocean environment with collision-free zone and static-obstacles zone; (2) The proposed path planning method with fast-marching-method-based ellipse guidance range (E-FMM) is able to optimize the angular energy while ensuring safety; (3) The proposed cooperative management system (including priority-target-assignment (PTA) with reward-mechanism genetic-optimization (RM-GO) and collision-avoidance (CA) guidance law with Tangent-based surge-varying wave-disturbances-observer (Tangent-SV-WDO)) can accomplish the mission of the rescue USVs. Comparative studies with the state-of-the-art methods demonstrate that the proposed cooperative path planning scheme is superior in terms of priority-target-assignment (PTA) and collision-avoidance (CA) of the actual rescue work.     

The Explanatory Role of Computation in Cognitive Science

Which notion of computation (if any) is essential for explaining cognition? Five answers to this question are discussed in the paper. (1) The classicist answer: symbolic (digital) computation is required for explaining cognition; (2) The broad digital computationalist answer: digital computation broadly construed is required for explaining cognition; (3) The connectionist answer: sub-symbolic computation is required for explaining cognition; (4) The computational neuroscientist answer: neural computation (that, strictly, is neither digital nor analogue) is required for explaining cognition; (5) The extreme dynamicist answer: computation is not required for explaining cognition. The first four answers are only accurate to a first approximation. But the ??devil?? is in the details. The last answer cashes in on the parenthetical ??if any?? in the question above. The classicist argues that cognition is symbolic computation. But digital computationalism need not be equated with classicism. Indeed, computationalism can, in principle, range from digital (and analogue) computationalism through (the weaker thesis of) generic computationalism to (the even weaker thesis of) digital (or analogue) pancomputationalism. Connectionism, which has traditionally been criticised by classicists for being non-computational, can be plausibly construed as being either analogue or digital computationalism (depending on the type of connectionist networks used). Computational neuroscience invokes the notion of neural computation that may (possibly) be interpreted as a sui generis type of computation. The extreme dynamicist argues that the time has come for a post-computational cognitive science. This paper is an attempt to shed some light on this debate by examining various conceptions and misconceptions of (particularly digital) computation.     

Au-Ni nanoparticles: Phase diagram prediction,synthesis, characterization,and thermal stability

The Au-Ni nanoparticles (NPs) were prepared by oleylamine solvothermal synthesis from metal precursors. The Au-Ni phase diagram prediction respecting the particle size was calculated by the CALPHAD method. The hydrodynamic size of the AuNi NPs in a nonpolar organic solvent was measured by the dynamic light scattering (DLS) method. The average hydrodynamic sizes of the nanoparticle samples were between 18 and 25 nm. The metallic composition of the AuNi NP samples was obtained by inductively-coupled plasma atomic emission spectroscopy (ICP-OES). The metallic fraction inside AuNi NPs was varied Au-(30–70) wt%Ni. The steric alkylamine stabilization was observed. The individual AuNi NPs were investigated by transmission electron microscopy (TEM). The dry nanopowder was also studied. The structures of the aggregated samples were investigated by scanning electron microscopy (SEM). The AuNi NPs reveal randomly mixed face-centered cubic (FCC) crystal lattices. The phase transformations were studied under inert gas and air. The samples were studied by differential scanning calorimetry (DSC).     

进化计算简要综述

介绍进化计算的起源与发展历史、进化计算的特点与分类、进化计算有关研究与应用现状、进化计算有关软件与国际信息交流等方面的基本情况。     

An optical biosensor for multi-sample determination of biochemical oxygen demand (BOD)

An optical biosensor for parallel multi-sample determination of biochemical oxygen demand (BOD) in wastewater samples has been developed. The biosensor monitors the dissolved oxygen (DO) concentration in water through an oxygen sensing film immobilized on the bottom of glass sample vials. The oxygen sensing film contains the tris(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) dye (Ru(dpp)) the luminescence intensity of which varies with oxygen concentration. A computer-controlled moving optrode head with four blue light emitting diodes (LEDs) was scanned sequentially under each sample vial. The luminescence signal was collected by an optical cable and transmitted to a photomultiplier tube (PMT) and processed by a microcomputer. The microbial samples (activated sludge and Bacillus subtilis were immobilized in a sol–gel composite material of silica and poly(vinyl alcohol)-grafted-poly(vinylpyridine) on the oxygen sensing film. The performance of the microbial film as a function of cell loading, thickness, temperature and pH and in the presence of heavy metals as well as its stability and service life have been investigated. The BOD value was determined from the rate of oxygen consumption by the microorganisms in the first 20 min. The BOD values obtained from this biosensor correlates well with the results of the conventional 5-day BOD test.     

GAO Feng~1,LI Wei~2,TANG Zon

tific Experiment Center of Guangxi Medical University,Nanning 530021,China)Objective:To investigate the mutation pattern of adenomatous polyposis coli(APC),Kirsten-ras(K-ras) and p53 genes in sporadic colorectal cancer tissues.Meth     

Impact of variational assimilation of MODIS thermodynamic profiles in the simulation of western disturbance

The present study was carried out to examine the impact of temperature and humidity profiles from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the numerical simulation of western disturbance (WD) using the three-dimensional variational (3D-Var) assimilation technique in the nonhydrostatic version of the Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) fifth-generation Mesoscale Model (MM5). The WD that affected northwest India during 8–11 February 2007 was chosen for the numerical simulations. The results show that there are large differences between the initial meteorological fields from the National Center for Environmental Prediction (NCEP) analysis (without satellite data; control experiment (CNT)) and the optimal initial conditions (with MODIS data; experiment (EXP)). The optimal initial condition showed that MM5 3D-Var had produced an analysis that fit the MODIS observations very well. The assimilation of the MODIS temperature and moisture profiles did not show much impact on the track of the WD but, more importantly, it showed evidence of impacting the rainfall intensity prediction by retarding the incorrect prediction of intense rainfall. The root mean square difference (RMSD) in predicted rainfall from EXP was lower than from CNT. The assimilation of MODIS data also showed a positive impact on the temperature prediction.     

邻-二(吡咯-2-甲酰胺基)亚苯对卤素阴离子识别的密度泛函研究

采用密度泛函B3LYP/LanL2DZ方法优化了气相以及在四氢呋喃(THF)、甲醇及二甲亚砜(DMSO)3种溶剂中邻-二(吡咯-2-甲酰胺基)亚苯(DPCP)及其卤素阴离子复合物的几何构型。从几何结构、电荷布居、结合能以及热力学参数等角度探讨复合物形成过程中受体与阴离子间的相互作用。研究结果表明:复合物稳定性与卤素离子的种类和溶剂极性有关,同一溶剂中,复合物DPCP-X~-以DPCP-F~-最稳定,随着卤素离子半径的递增,稳定性逐渐下降,F~-,Cl~-在气相和3种溶剂中都能形成稳定的复合物,Br~-复合物只在气相稳定,在选定的3种溶剂中均不能形成稳定的复合物,而I~-无论在气相还是在3种溶剂中均不能形成稳定的复合物;同一复合物DPCP-X~-稳定性随溶剂极性的增大逐渐减小。利用相同的理论方法预测了在3种溶剂中DPCP与OH~-及CN~-的相互作用能力及复合物的稳定性。     

Automatic diagnosis with genetic algorithms and case-based reasoning

This article describes the application of Machine Learning (ML) techniques to a real world problem: the Automatic Diagnosis (classification) of Mammary Biopsy Images. The techniques applied are Genetic Algorithms (GA) and Case-Based Reasoning (CBR). The article compares our results with previous results obtained using Neural Networks (NN). The main goals are: to efficiently solve classification problems of such a type and to compare different alternatives for Machine Learning. The article also introduces the systems we developed for solving this kind of classification problems: Genetic Based Classifier System (GeB-CS) for a GA approach, and Case-Based Classifier System (CaB-CS) for a CBR approach.     

氯酚类污染物的光催化降解活性与结构参数的关系研究

为进一步阐明光催化降解常数与氯酚类的分子结构关系,引入灰色关联分析方法,运用灰色关联理论,通过均值化处理使相关因子的实验数据无量纲化,计算出作为描述符的14种结构参数对于光催化降解常数影响程度的排序,并结合变量的物理意义作简要分析,结果表明,对光催化影响最大的参数是偶极距、(E_(lumo)-E_(homo))~2、E_(lumo)-E_(homo)、E_(homo)、E_(lumo) E_(homo)及碳原子的平均静电荷。     

Book Reviews

Book review in this Article Fumio Kodama (1995) Emerging Patterns of Innovation (sources of Japan's Technological Edge) Frank-Jurgen Richter (ed.) 1996, The Dynamics of Japanese Organizations, Routledge Alice Bredin (1996) The Virtual Office Survival Handbook Lisa Shaw (1996) Telecommutel Garth Hallberg, 1995, A12 Consumers Are Not Created Equal, The Differential Strategy for Brand Loyalty and Profits     

槐定碱和苦参碱在不同阳离子胶束介质中的电化学行为

以玻碳电极(GCE)为工作电极,用循环伏安法(Cyclic voltammetry,CV)分别研究了槐定碱(Sophoridine,sR)和苦参碱(Matrine,MT)在十二烷基三甲基溴化铵(Dodecyhrimethylammonium,DTAB)、十四烷基三甲基溴化铵(Tetradecyitrimethylammonium,TYAB)、十六烷基三甲基溴化铵Hexadecyhrimethylammonium,CTAB)和溴代十六烷基吡啶(Cetylpyrid bromide,CPB)阳离子胶束中的电化学行为,并对其进行比较.果表明,在不同阳离子胶束体系中sR和MT的氧化峰电流,p均有所降低,氧化峰电位Еp均发生正移.同时研究了pH在2.0～9.5范围及胶束存在下介质pH值及不同浓度NaCl支持电解质对SR和MT电化学行为的影响,并给出合理的解释.运用计时库仑法(Chronocoulometry,CC),计时电流法(chmnoamperometry,CA)测定了有无胶束存在时SR和MT的扩散系数D,电荷转移系数α和电极反应速率常数缸,并对其进行了比较.结果表明,在不同介质中SR和MT的动力学参数大小顺序为:H2O>DTAB>TYAB>CTAB>CPB.     

Theoretical study of aluminum arsenide clusters: equilibrium geometries and electronic structures of Al(n)As(n) (n=1-4)

The geometry, electronic configurations, harmonic vibrational frequencies and stability of the structural isomers of Al(n)As(n) clusters (n=1-4) have been investigated using density functional theory. For dimers and trimers, the lowest energy structures are planar cumulenic rings (IIs, VIs) with D(nh) symmetry. The caged structure with T(d) symmetry (IXs) lie lowest in energy among the tetramers. The AlAs bond dominates the structures for many isomers so that one preferred dissociation channel is loss of the AlAs monomer. The atomic charges, hybridization and chemical bonding in the different structures are also discussed. Comparisons with valence-isoelectronic Si(2n), Al(n)P(n) and Ga(n)As(n) clusters of same size, the properties of the aluminum arsenide clusters are analogous to those of their corresponding Al(n)P(n), Si(2n) counterparts. The results can explain the modification and refinement of Si phase in AlSi alloy in the molecular level.     

A compact wideband circularly polarized antenna with two pairs of driven patch arrays

In this article, a new wideband circularly polarized (CP) antenna is presented. The antenna is composed of a circular‐loop feeding structure which provides sequential phase (SP), four primary‐parasitic crown patches and four secondary‐parasitic crown patches. The circular‐loop SP structure is used to feed the two pairs of crown patches by a capacitively coupled way. The presented antenna features a wide 10‐dB impedance bandwidth (IBW) of 23% (6 GHz, 5.31‐6.69 GHz), and a wide 3‐dB axial ratio bandwidth (ARBW) of 11.1% (5.875 GHz, 5.55‐6.2 GHz). The proposed antenna features compact structure and broad 3 dB‐ARBW, which could include the WLAN (5.725‐5.85 GHz), ITS (5.8 GHz), and WIFI (5.85‐5.925 GHz) band.     

Speaker recognition utilizing distributed DCT-II based Mel frequency cepstral coefficients and fuzzy vector quantization

In this paper, a new and novel Automatic Speaker Recognition (ASR) system is presented. The new ASR system includes novel feature extraction and vector classification steps utilizing distributed Discrete Cosine Transform (DCT-II) based Mel Frequency Cepstral Coefficients (MFCC) and Fuzzy Vector Quantization (FVQ). The ASR algorithm utilizes an approach based on MFCC to identify dynamic features that are used for Speaker Recognition (SR). A series of experiments were performed utilizing three different feature extraction methods: (1) conventional MFCC; (2) Delta-Delta MFCC (DDMFCC); and (3) DCT-II based DDMFCC. The experiments were then expanded to include four classifiers: (1) FVQ; (2) K-means Vector Quantization (VQ); (3) Linde, Buzo and Gray VQ; and (4) Gaussian Mixed Model (GMM). The combination of DCT-II based MFCC, DMFCC and DDMFCC with FVQ was found to have the lowest Equal Error Rate for the VQ based classifiers. The results found were an improvement over previously reported non-GMM methods and approached the results achieved for the computationally expensive GMM based method. Speaker verification tests carried out highlighted the overall performance improvement for the new ASR system. The National Institute of Standards and Technology Speaker Recognition Evaluation corpora was used to provide speaker source data for the experiments.