全文获取类型
收费全文 | 888篇 |
免费 | 62篇 |
国内免费 | 31篇 |
专业分类
电工技术 | 27篇 |
综合类 | 51篇 |
化学工业 | 23篇 |
金属工艺 | 86篇 |
机械仪表 | 21篇 |
建筑科学 | 4篇 |
矿业工程 | 2篇 |
能源动力 | 47篇 |
轻工业 | 10篇 |
石油天然气 | 5篇 |
武器工业 | 3篇 |
无线电 | 94篇 |
一般工业技术 | 28篇 |
冶金工业 | 375篇 |
自动化技术 | 205篇 |
出版年
2025年 | 1篇 |
2024年 | 6篇 |
2023年 | 12篇 |
2022年 | 23篇 |
2021年 | 17篇 |
2020年 | 22篇 |
2019年 | 11篇 |
2018年 | 13篇 |
2017年 | 21篇 |
2016年 | 15篇 |
2015年 | 13篇 |
2014年 | 31篇 |
2013年 | 26篇 |
2012年 | 50篇 |
2011年 | 64篇 |
2010年 | 85篇 |
2009年 | 69篇 |
2008年 | 62篇 |
2007年 | 71篇 |
2006年 | 85篇 |
2005年 | 52篇 |
2004年 | 68篇 |
2003年 | 56篇 |
2002年 | 30篇 |
2001年 | 25篇 |
2000年 | 14篇 |
1999年 | 8篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有981条查询结果,搜索用时 0 毫秒
1.
The solidification structure, microstructure evolution during rolling and precipitates with nanometers in dimension of the low carbon steels produced by CSP process with thin slabs have been studied in recent years. Important differences in microstructure and mechanical properties between the CSP products and the conventional one were observed. These differences may arise from the much rapider solidification rate and cooling rate after casting of the thin slabs. Some aspects of the microstructure for the low carbon steels of the CSP thin slabs are summarized and compared with the conventional one. 相似文献
2.
龙明建 《金属材料与冶金工程》2004,32(6):3-5
介绍了涟钢CSP产品的现状及其性能。为调整产品结构,提高企业的市场竞争能力,提出了未来开发CSP板带材产品的几点建议。 相似文献
3.
4.
采用包钢CSP(Compact Strip Production)薄板坯连铸连轧工艺生产L245钢为原料进行螺旋焊管焊接生产,针对生产中焊缝裂纹问题对焊缝区的形貌、组织进行了观察,并对焊缝进行拉伸性能和X射线检验。分析表明,母材与热影响区的交界处(即偏向热影响区的“过渡区”)是L245焊管力学性能最脆弱处,珠光体的形貌是影响其拉伸性能的关键因素。 相似文献
5.
6.
7.
介绍了包钢CSP厂通过成分调整和工艺优化,研究出适合冷轧生产的热轧低碳钢带生产工艺。IM时通过严格加热炉热工制度和换辊制度等,解决了CSP工艺生产的冷轧用低碳钢热带的表面质量问题,用其生产的冷带成形性能优良,可作为深冲、超深冲使用。 相似文献
8.
9.
Solar power technologies will have to become a major pillar in the world's future energy system to combat climate change and resource depletion. However, it is unclear which solar technology is and will prove most viable. Therefore, a comprehensive comparative assessment of solar technologies along the key quantitative and qualitative competitiveness criteria is needed. Based on a literature review and detailed techno-economic modeling for 2010 and 2020 in five locations, we provide such an assessment for the three currently leading large-scale solar technologies. We show that today these technologies cannot yet compete with conventional forms of power generation but approach competitiveness around 2020 in favorable locations. Furthermore, from a global perspective we find that none of the solar technologies emerges as a clear winner and that cost of storing energy differs by technology and can change the order of competitiveness in some instances. Importantly, the competitiveness of the different technologies varies considerably across locations due to differences in, e.g., solar resource and discount rates. Based on this analysis, we discuss policy implications with regard to fostering the diffusion of solar technologies while increasing the efficiency of policy support through an adequate geographical allocation of solar technologies. 相似文献
10.
Refinement-closed security properties allow the verification of systems for all possible implementations. Some systems, however, have refinements that do not represent possible implementations. In particular, real instantiations of abstract systems comprising security-critical components surrounded by maximally hostile unrefined components are often characterised only by compositions of refinements of the abstract system's components, rather than all refinements of the abstract system. In this case, refinement-closed security properties that examine multiple behaviours of a system at once can be falsely violated by the presence of inconsistent pairs of behaviour arising from different, incompatible refinements of the system's components.We show how to weaken a class of such properties, which includes both information flow and causation properties, to allow them to be applied to these sorts of abstract systems. The weakened properties ignore all pairs of inconsistent behaviour that would have violated the original property from which they are derived. We also show how to adapt existing automated tests for these properties to allow them to be used to test for their weakened counterparts instead. This enables greater flexibility in the application of these sorts of properties to compositions of nondeterministic components. 相似文献