金相检验在承压类设备检验中的应用     

周兵  李越胜  邵春文  吴士强 《中国科技信息》2012,(10):66

承压类设备主要有四种失效形式,金相检验是其有效检验手段。本文阐述了现场检验中金相检验取样的方法和难点,进一步阐述了金相检验的新技术。  相似文献   

青年公务员压力及其应对策略     

刘成玉 《毕节学院学报》2010,28(5):110-114

青年公务员压力对公务员工作效率的影响日渐受到相关学者和社会的关注。了解青年公务员的压力状况并对之进行有效的管理,既是社会组织之需,也是人力资源管理研究的一个重要课题。为帮助青年公务员尽快适应自己的岗位角色要求,增强自身的角色适应和心理适应能力,从公务员的压力源、压力因素等方面进行探讨,并在此基础上提出几种有效的应对策略。  相似文献   

我国教材图书市场并购的必要性与并购主体选择     

蒋雪湘  胡振华 《出版科学》2010,18(1):43-46,42

分析我国教材图书市场的特征,指出该市场存在刚性进入壁垒,导致教材图书市场资源配置效率低。通过对教材图书市场并购效应的分析,提出我国教材图书市场并购的必要性,并运用生存技术检验法则测定教材图书企业最优效益规模,为并购主体的选择提供借鉴意义。  相似文献   

Surviving Being Dark: A Pedagogy of the Sacred for Survival in a Divided Society     

Karen E. Mosby 《Religious education (Chicago, Ill.)》2020,115(3):304-314

Abstract

Historically, Blacks have out of necessity prioritized survival in educating their younger generations for existence in the racially hostile and divided context of the U.S. This education and religious education has occurred formally and informally in homes, schools, community organizations, and in congregations. This paper examines three aspects of survival: survival and emancipatory education, survival and justice, and survival with emerging Black generations. Three examples will be offered that highlight each aspect of survival. The examples will demonstrate how education generally and religious education in particular have undergirded pedagogies of the sacred for the survival of Black life.  相似文献   

老舍的精英意识及其流变     

杨英伟 《巢湖学院学报》2008,10(2):67-71

被誉为"平民作家"的老舍其实具有独特的精英意识。因其不同的生存语境,这种精英意识在不同阶段的小说中呈现出动态的流变。寄予在"二李"身上实干的精英意识,与老舍独处英伦,渴慕西方文化的境遇有关。小蝎和大鹰精英意识的缺失则隐含了老舍对现实境遇的失望和愤怒;瑞宣和钱默吟经过精神裂变,成长为民族精英,则说明经过民族战争的洗礼,老舍的文化更新意识得到了释放和升华。  相似文献   

基于施耐德变频器调速技术在高楼恒压供水系统的设计与实现     

曾繁玲 《内江师范学院学报》2008,23(4):24-26

以广东省罗定市龙庭花园居住小区的恒压供水系统为例,详细介绍了应用施耐德变频器实现恒压供水的结构和原理、控制方式及变频器的选择和参数设置．  相似文献   

Optimal design of pressure vessel using an improved genetic algorithm     

Peng-fei Liu  Ping Xu  Shu-xin Han  Jin-yang Zheng 《浙江大学学报(A卷英文版)》2008,9(9):1264-1269

As the idea of simulated annealing （SA） is introduced into the fitness function, an improved genetic algorithm （GA） is proposed to perform the optimal design of a pressure vessel which aims to attain the minimum weight under burst pressure constraint. The actual burst pressure is calculated using the arc-length and restart analysis in finite element analysis （FEA）. A penalty function in the fitness function is proposed to deal with the constrained problem. The effects of the population size and the number of generations in the GA on the weight and burst pressure of the vessel are explored. The optimization results using the proposed GA are also compared with those using the simple GA and the conventional Monte Carlo method.  相似文献   

超临界CO_2协助改性丝素蛋白纤维     

彭琦  许群 《洛阳工业高等专科学校学报》2008,18(1)

超临界CO2做溶剂及携带剂,协助甲基丙烯酸甲酯/丙烯酸改性丝素蛋白纤维.研究了各种实验条件对纤维增重率的影响.插嵌时间4 h后增重率变化不再明显;改变压力,增重率有极值出现;随单体浓度的增加,增重率增大.  相似文献   

带防腐层在役压力容器表面磁粉探伤灵敏度的试验研究     

王彤 《洛阳工业高等专科学校学报》2008,18(1)

采用人工裂纹试样的方法,模拟压力容器涂刷油漆防腐层的状况进行磁粉探伤,得出了油漆防腐层厚度与裂纹检出灵敏度的定量关系;结合CVDA<压力容器缺陷评定>规范,探讨了试验方法对一般在役压力容器带有油漆的情况下进行磁粉探伤检验的可行性.研究表明:采用交流磁化法进行探伤,当漆层厚度小于250 μm时灵敏度影响较小,同时亦表示不宜使用直流磁化方法.该结论对承受低应力工况条件下的压力容器安全质量检验和评估有重要参考价值.  相似文献   

Finite element modeling for analysis of cracked cylindrical pipes     

SUNG Wen-pei GO Cheer-germ SHIH Ming-hsiang 《浙江大学学报(A卷英文版)》2007,8(9):1373-1379

The characteristic properties of shell element with similar shapes are used to generate a so-called super element for the analysis of the crack problems for cylindrical pressure vessels. The formulation is processed by matrix condensation without the involvement of special treatment. This method can deal with various singularity problems and it also presents excellent results to crack problems for cylindrical shell. Especially,the knowledge of the kind of singular order is not necessary in super element generation; it is very economical in terms of computer memory and programming. This method also exhibits versatility to solve the problem of kinked crack at cylindrical shell.  相似文献