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171.
郭中醒  权利 《微特电机》2006,34(7):32-33,40
简述了和微电机相关的微加工生产中的方法,介绍了微型机电部件成型的实现途径。  相似文献   
172.
对某工厂废水处理用液压柱塞泵的弹簧座进行了受力分析、强度计算和金相检验,找出了弹簧座内表面产生晶间腐蚀的原因和解决的方法.  相似文献   
173.
本文从理论和实践上综述了磁化水的特性、磁化机理、国内外的发展近况及其使用安装等。该法用于锅炉和各类冷却水处理有广泛的前景。  相似文献   
174.
A mathematical model was developed to simulate water movement, mass transport, and nitrogen transformations in soils during wastewater applications. The model is one-dimensional and based on the Galerkin finite-element method. The submodel of mass transport of nitrogen incorporates the convection-dispersion processes of ammonium and nitrate nitrogen, nitrification, denitrification, ammonium exchange and uptake of ammonium and nitrate ions. The accuracy and validity of the proposed model was examined by comparison with an explicit-implicit finite-difference model results. The model was used for simulation of water and nitrogen dynamics during wastewater application in homogeneous and multi-layered soils under different N concentration, rate, duration and scheduling of application.  相似文献   
175.
Reviews the book, The chemically dependent: Phases of treatment and recovery edited by Barbara C. Wallace (see record 1992-98403-000). While this book is ambitious, interesting, educational, and useful, it is also disappointing, repetitious, and incomplete. Because it tries to accomplish so much, it may appear to have succeeded too little. This book is organized around, and explicative of, several basic ideas which might have been controversial if not heretical had this book been published ten years ago. Section I, purporting to link specific "phases of recovery" to particular forms and functions of treatment, will certainly be useful for novice clinicians but falls short of its overstated goals and is thereby disappointing. Section II is a collection of moderately redundant chapters describing the etiology and treatment of substance abusers from the viewpoints of psychoanalytic, psychodynamic, ego psychology, and object-relations theorists and therapists. Section III focuses on cognitive-behavioral, self-help, and relapse-prevention treatments. Section IV is quite uneven in quality of writing and applicability of content, and could have benefited from closer editorial scrutiny or selectivity. The final section focuses on special needs of particular subpopulations of substance abusers: African-Americans, prison inmates, HIV/AIDS patients, persons who are homeless, those who have been sexually and physically abused, and others. According to the reviewer this is not the best book on substance abuse treatment, but it does present some clinically useful ideas and it is worth reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
176.
This paper presents a new method for the tolerance analysis of plating and heat treatment operations. It is suitable for both manual and computerised tolerance analysis. The new method uses a datum-hierarchy tree to identify tolerance stacks and a stock removal set matrix to calculate the positions of surfaces created during the manufacturing sequence. A tolerance chart is used to associate stock removal sets with the geometry of the workpiece, to show the manufacturing sequence, and to record the operation data and the tolerance analysis results. Plating and heat treatment operations are represented as edges in the tree, so that for each operation (edge) the input and output nodes represent consecutive surfaces in a stock removal set. Rules are given for calculating the tolerance stackups and the positions of the surfaces in the stock removal sets. The method is illustrated with an example.  相似文献   
177.
通过对典型振冲挤密法施工方法的研究,分析了该方法的加固机理,指出它可提高地基承载力、减少沉降和不均匀沉降,且能达到地基抗地震、抗液化能力的效果。  相似文献   
178.
Laboratory-scale and parametric experiments of SO2 and NOx removal from the simulated combustion gas by pulsed corona discharge have been performed by changing the combustion gas composition and temperature, the electrode configuration of plasma reactor, and the polarity of high-voltage electrode. The following results are obtained: 1) the higher the concentration of H2O and O2, the higher the efficiency of desulfurization and denitrification at the same specific input; 2) the pulsed corona discharge with a voltage pulsewidth as short as 200 ns of negative polarity shows the possibility to attain almost 90 percent deSOx and deNOx efficiency at the specific discharge input of 20 J/g, which is almost the same as the specific input in the electron-beam process; 3) the deNOx characteristics show a little temperature dependence in the range of 70 to 130°C, but the deSOx efficiency increases rapidly in the temperature region below 100°C suggesting the thermochemical dependence of deSOx reaction; 4) when desulfurization and denitrification proceed, the white dendritic powder deposits on the plasma reactor whose composition is identified to be 49 mol% (NH4)2SO4 and 47 mol% of 2NH4NO3 · (NH4)2SO4, and the ratio of SO2, NO and NH3 of the deposit is almost equal to that of supplied gas.  相似文献   
179.
吴硕 《山西建筑》2006,32(20):13-14
通过对广州市猎德污水处理厂的介绍,说明本工程厂区平面根据规划用地、工艺流程、外部及内部环境因地制宜进行布置,建筑立面造型综合考虑厂房的不同使用功能,力求打破以往的工业建筑模式,建成处处以人为本的生态花园式厂房。  相似文献   
180.
李春生 《土工基础》2004,18(1):58-59
详细论述了南冲高架桥 6-2桩的检测过程 ,说明了岩溶地质对桩基质量的影响 ,并对此影响和预防措施进行了论述  相似文献   
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