求解二维结构-声耦合问题的一种直接方法

本文基于传递矩阵法(TMM)和虚拟边界元法(VBEM)，提出了一种求解在谐激励作用下二维结构-声耦合问题的直接法。文中对任意形状的二维弹性环建立了一阶非齐次运动微分方程组，便于用齐次扩容精细积分法求解，对于含有任意形状孔穴的无穷域流体介质的Helmholtz外问题，采用复数形式的Burton-Miller型组合层势法建立了虚拟边界元方程，保证了声压在全波数域内存在唯一解。根据叠加原理并结合最小二乘法，提出了一种耦合方程的直接解法，由于该方法不存在迭代过程，因而具有较高的计算精度和效率。文中给出了二个典型弹性环在集中谐激励力作用下声辐射算例，计算结果表明本文方法较通常采用的混合FE／BE法更为有效。     

An investigation into physicochemical characteristics of ash produced from combustion of oil palm biomass wastein a boiler

Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material.     

实用户外视频监控异常检测策略

树枝叶等植物的晃动是造成户外监控背景复杂性的主要因素。该文提出一种基于视频分析的运动对象检测策略，利用快慢双背射模型检测运动变化像素，并通过邻域像素的棚关性检测消除虚假运动对象。实验表明此算法对户外监控不但速度快而且检测效果理想，满足实用化要求。     

改善磁盘阵列性能的方法

磁盘阵列是解决计算机Ｉ／Ｏ瓶颈问题的有效方法之一，通过对现有磁盘阵列结构的研究，提出了４种改善磁盘阵列性能的方法，即良分利用磁盘带宽，平衡多盘的负载，减少奇偶检验数据存取时间和磁盘阵列Ｃａｃｈｅ技术等，分析结果表明：在事务处理应用领域，利用Ｃａｃｈｅ来把小写转化为大写可大大改善目前一般情况下，以一道数据大小来作为磁盘的基本存取大小是合适的选择，磁盘阵列负载平衡设计不足是指正常模式下系统请求在多盘间     

The levels of integrin alpha v beta 5 may predict the susceptibility to adenovirus-mediated gene transfer in human lung cancer cells

Adenovirus mediated transfer of growth-inhibiting molecules, such as p53 shows promise as an effective method of suppressing the growth of cancer cells. As the basis for in vivo studies, we examined transfection efficiency using 15 human lung cancer cell lines that differ in their endogenous p53 status. When infected with an adenovirus expressing bacterial beta-galactosidase, the different cell lines showed different levels of beta-galactosidase activity. We found a correlation between the level of integrin alpha v beta 5, which is thought to be an adherence receptor for adenoviruses, and the expression level of the transferred gene, suggesting that gene expression is largely dependent on the infection efficiency. Growth inhibition was induced in all cell lines tested following infection with an adenovirus containing p53, regardless of the genetic status of their endogenous p53 provided a sufficient amount of p53 protein was expressed. Our results (1) confirm that the examination of the susceptibility of target cancer cells to an adenovirus is important when considering performing adenovirus-mediated gene transfer and for evaluating its therapeutic effects; and (2) suggest that the quantification of integrin alpha v beta 5 may be a good way of predicting the susceptibility of cells to adenoviral vectors.     

基于STEP的零件加工工艺计划模型

为了满足ＣＩＭＳ环境下工艺系统与其它系统集成的需要，建立了标准工艺计划模型具十分重要的意义。本文描述了一个基于ＳＴＥＰ的零件加工工艺计划模型，介绍了建立这一模型的关键技术，给出了参照ＳＴＥＰ建立工艺计划模型的方法。     

60m高度处单片露天超高混凝土悬臂墙的设计与施工

通过采用竖向预应力技术 ,解决了 60m高度处单片 8m高悬臂钢筋混凝土墙根部裂缝宽度超过规范限值的问题 ;采用将预应力钢绞线顶端锚固于墙高中段等结构和施工措施 ,控制墙体长细比不超过 3 0 ,减少了由于长细比过大对墙体承载力的不利影响     

胜科1井钻井事故的预防与处理

胜科1井设计井深7 000 m,完钻井深7 026 m。在该井钻井过程中,针对上部大尺寸钻头破岩效率低、大井眼井壁稳定性差、大段盐膏层、膏岩层的塑性蠕变和塑性流动造成井眼复杂、超深井高温高压给钻井液性能的控制和水泥浆调控等带来的一系列技术难题,制定了一整套预防井下事故和复杂情况的技术措施,从而确保了该井的钻探成功。该井在钻井过程发生了2次断钻具事故和1次卡钻事故,根据超深井的特点,采取了较为稳妥的处理措施,同时,有针对性地研制了高效铣环和PDC钻头专用打捞器,3次事故处理均获得了成功,共耗时38.5 d。详细介绍了该井所采取的预防和处理钻井事故的技术措施,可为其他超深井的钻井施工提供一定的借鉴。     

Study on Adsorption Behavior of Rare Earth Complexes on Nanometer-Size Titanium Dioxide with ICP-AES

Inrecentyears ,rareearthelements (REEs)havebeenwidelyusedinfunctionalmaterials ,cata lystsandotherproductsinindustry ,diagnosisreagentsofmagneticresonanceimaging (MRI)inmedicineandsomefertilizersinagricultureespeciallyinChina .However,asaresultoftheirusage ,moreandmoreREEsaregettingintotheenvironment,andalsointohumanbodyviafoodchain[1,2 ] .Itisnotclearwhetherrareearthelementsareessentialforman ,soitisveryurgenttostudythebiologicaleffectofrareearthelementsinhumanhealthandenvironment .Inthes…     

纳米技术在中药开发中的应用

本文综述了纳米科技与中药制剂相结合的发展，阐述了纳米中药的概念、特性，介绍了纳米中药的制备技术，另外探讨了收集纳米粒子的方法，最后，着重展望了纳米技术在中药制剂中广泛的应用前景。