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1.
通过试验设计测定不同参数热处理后材料的力学性能,以及组织结构分析,获得P91钢的热处理工艺参数,从而制定出P91钢的热处理工艺,总结出回火温度是影响P91钢管质量的重要参数,回火加热时间也对钢管力学性能有着重要的影响,为P91钢管生产提供了一种可供参考的热处理规范。  相似文献   

2.
哈尔滨热电厂改造工程P91主蒸汽管道安装初期,有2只焊缝硬度值出现偏高情况,通过试验和分析找出了原因。P91钢材焊接时,层间温度应严格控制在250~300℃区间内,选择较小的焊接线能量是控制硬度值的主要措施。  相似文献   

3.
通过对T-P92钢管道内壁堆焊Inconel 625的工艺探讨,研究了堆焊接头的组织和力学性能。研究结果表明,通过合理的焊接工艺和热处理,堆焊焊缝整齐,侧壁熔合良好,无气孔等缺陷。P92钢热影响区的组织为马氏体,并分为粗晶区和细晶区。堆焊界面中P92钢粗晶区的硬度最大,经热处理后硬度降低。化学成分符合要求,Fe5%,机械性能良好。  相似文献   

4.
对于受内压容器,防止应力腐蚀最常用的方法为焊后进行整体热处理,对不同强度级别的材料相应控制其热处理后硬度.对于严重应力腐蚀环境下,同时进行材料无损检测,控制材料中杂质尤其是S、P含量、改善操作工况等方法,能很好地满足安全使用要求.  相似文献   

5.
文章通过制定CrWMn铜的热处理工艺,测定在各种热处理情况下试样的硬度和耐磨性,并进行金相组织分析,得出了淬火加低温回火可以提高CrWMn的硬度和耐磨性。  相似文献   

6.
通过对600MW发电机组三级过热器SA213-T91管子焊接热影响区出现的裂纹进行宏观及微观分析,阐述了T91的组织和机械性能、使用条件及焊接裂纹的产生机理,提出T91小管在焊接、热处理及使用中应注意的几个问题,充分了解了它的优、缺点。  相似文献   

7.
张强  于连水 《价值工程》2010,29(13):160-160
大管径厚壁P91的焊后热处理,国内目前普遍采用的电阻加热方式存在一定的弊端,周向及径向存在温度差,造成局部回火不存分或超过材料的Ac1,对材料的使用性能造成影响,而感应加热设备因其加热原理的不同,可以很好地改善这一状况。  相似文献   

8.
文章通过用化学分析、金相检验和断口分析等方法,针对板簧热处理在产品的设计、工艺设计、热处理设备均能满足产品质量要求的前提下,产生硬度不足和钢板弹簧总成在使用过程中断裂的簧片,进行检验分析.结果表明,员工在生产过程中工作责任心与质量意识淡薄,认识、理解不足,是导致簧片硬度不足和钢板弹簧总成在使用过程中簧片断裂的一个重要的因素.  相似文献   

9.
高淬透性材质,心部硬度高,脆性大,塑韧性小.由于热处理变形,导致产品在热处理后矫直困难,个别产品发生断裂.通过试验分析,调整结构上的应力集中,增加产品键槽圆滑过渡.设计新淬火工艺,降低产品心部硬度,提高其塑韧性,减少断裂问题发生,提高产品一次校直率.  相似文献   

10.
对于受内压容器,防止应力腐蚀最常用的方法为焊后进行整体热处理,对不同强度级别的材料相应控制其热处理后硬度。对于严重应力腐蚀环境下,同时进行材料无损检测,控制材料中杂质尤其是S、P含量、改善操作工况等方法,能很好地满足安全使用要求。  相似文献   

11.
This paper outlines the ICT statistical developments that the ABS has undertaken over recent years. These developments have been on both the supply side (ICT industry) and the demand side (use of IT by sector). The content of ABS ICT surveys has changed significantly over the last few years and are expected to develop further in line with industry changes and emerging policy needs.
Recent developments in household collections have been the inclusion of IT use questions in the 2001 Census of Population and Housing and in various ABS social surveys such as Children's Participation in Culture and Leisure Activities. Annual business IT use surveys are now conducted and include topics such as Internet commerce and IT security. Biennial ICT industry surveys are conducted to provide data on ICT production, imports and exports, ICT industry employment, performance and structure information. An Internet activity survey is run every six months and provides regional Internet access details and infrastructure details on Internet service providers.
A major development for 2002–03 will be the compilation of an ICT satellite account. ABS intends to produce an ICT Information Development Plan to guide its future statistical development work in the ICT field.  相似文献   

12.
En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.  相似文献   

13.
Several US counties and local governments have recently considered a novel solution to the foreclosure crisis. They plan to use eminent domain to compel the owners of mortgage debt—and specifically of private‐label mortgage‐backed securities—to sell the debt to the government at a price reflecting the loan's market value. The government would then restructure the debt and resell it to new investors. The plans are striking because—in contrast to both development‐driven eminent domain and the federal subprime bank bailout—they would force investors to assume asset devaluation and increased long‐term risk. Notably, the plans have emerged as an instance of financialization‐focused politics in suburbs and suburban cities of color, specifically majority‐black and ‐Latino/a suburbs. Local support for the plans, we argue, is rooted in the long‐term disinvestment of these ‘suburbs of exception', which became targets of subprime lending and eventually sites where the ‘financial exception' has been localized. But these demographic shifts, fragmentation and fiscal pressures have at the same time created a suburban political terrain in which the plans have gained their strongest political support.  相似文献   

14.
Serendipity – the notion of making surprising and valuable discoveries – plays a major role in the success of individuals and organizations alike. Previous research has established the importance of serendipity and identified important individual- and organizational-level antecedents. However, the literature has been dispersed and the boundaries of the concept have been blurry, leading to a lack of conceptual clarity and structure, and thus limiting validity and managerial actionability. Based on a systematic literature review, I synthesize existing management-related research on serendipity and explicate the emergence and composition of serendipity in the organizational context. I first identify three necessary conditions that differentiate serendipity from related concepts such as luck or targeted innovation: agency, surprise, and value. Then, I draw from the literature on sensemaking, event-based theorizing, and quantum-based approaches to management to conceptualize the process of cultivating serendipity in the organizational context as a process of enabling potentiality and materialization, and develop a multi-level theory of (cultivating) serendipity. This conceptualization contributes to our collective understanding of how, why, and when (i.e., under what conditions) organizations can leverage the value in the unexpected, which opens up fruitful avenues for further research.  相似文献   

15.
NGOs in Bangladesh have been recognized as effective change agents in the socio-economic arena throughout the world. Their contributions in micro credit, non-formal education and primary health care are widely known. NGOs play a significant role in society. NGO accountability, as a result, has become a critical issue. NGO accountability in Bangladesh has been examined here in relation to patrons, clients and themselves. Of the three relationships only accountability to patrons is in a near satisfactory state. Accountability to clients is handicapped by lack of opportunities of beneficiaries to participate meaningfully in NGO policy making. Accountability to themselves is adversely affected due to the adherence to a strictly hierarchical system and the influence of founding and charismatic NGO leaders.  相似文献   

16.
There has been much discussion regarding the possible decline and weakening of national systems of human resource management (HRM). Yet, culture and institutions are often cited as the major stumbling blocks to this outcome. Such constraints may dissipate in the analysis, particularly if ‘regional clusters’ are considered where geographic and cultural closeness and ‘openness’ to similar economic pressures exist. In such cases, it might be postulated that convergence in HRM will occur. We argue that China, Japan and South Korea represent such a cluster. This article examines these countries, to see if a degree of convergence is taking place and if it is towards an identifiable ‘Asian’ model of HRM. A model of change is presented that distinguishes between levels of occurrence and acceptance. Details of the development and practice of HRM in each country are then set out. The article ends with a discussion and implications section and a brief conclusion.  相似文献   

17.
While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.  相似文献   

18.
Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.  相似文献   

19.
This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.  相似文献   

20.
When sampling a batch consisting of particulate material, the distribution of a sample estimator can be characterized using knowledge about the sample drawing process. With Bernoulli sampling, the number of particles in the sample is binomially distributed. Because this is rarely realized in practice, we propose a sampling design in which the possible samples have a nearly equal mass. Expected values and variances of the sample estimator are calculated. It is shown that the sample estimator becomes identical to the Horvitz–Thompson estimator in the case of a large batch-to-sample mass ratio and a large sample mass. Simulations and experiments were performed to test the theory. Simulations confirm that the round-off error due to the discrete nature of particles is negligible for large sample sizes. Sampling experiments were carried out with a mixture of PolyPropylene (PP) and PolyTetraFluorEthylene (PTFE) spheres suspended in a viscous medium. The measured and theoretical variations are in good agreement.  相似文献   

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