全文获取类型
收费全文 | 11897篇 |
免费 | 964篇 |
国内免费 | 638篇 |
专业分类
电工技术 | 527篇 |
技术理论 | 6篇 |
综合类 | 1324篇 |
化学工业 | 1894篇 |
金属工艺 | 271篇 |
机械仪表 | 794篇 |
建筑科学 | 2511篇 |
矿业工程 | 801篇 |
能源动力 | 458篇 |
轻工业 | 623篇 |
水利工程 | 201篇 |
石油天然气 | 375篇 |
武器工业 | 41篇 |
无线电 | 368篇 |
一般工业技术 | 1066篇 |
冶金工业 | 801篇 |
原子能技术 | 41篇 |
自动化技术 | 1397篇 |
出版年
2024年 | 45篇 |
2023年 | 208篇 |
2022年 | 429篇 |
2021年 | 411篇 |
2020年 | 476篇 |
2019年 | 336篇 |
2018年 | 268篇 |
2017年 | 308篇 |
2016年 | 344篇 |
2015年 | 426篇 |
2014年 | 857篇 |
2013年 | 761篇 |
2012年 | 938篇 |
2011年 | 906篇 |
2010年 | 779篇 |
2009年 | 678篇 |
2008年 | 544篇 |
2007年 | 702篇 |
2006年 | 682篇 |
2005年 | 539篇 |
2004年 | 443篇 |
2003年 | 408篇 |
2002年 | 365篇 |
2001年 | 305篇 |
2000年 | 235篇 |
1999年 | 219篇 |
1998年 | 159篇 |
1997年 | 143篇 |
1996年 | 86篇 |
1995年 | 79篇 |
1994年 | 76篇 |
1993年 | 33篇 |
1992年 | 45篇 |
1991年 | 34篇 |
1990年 | 26篇 |
1989年 | 16篇 |
1988年 | 24篇 |
1987年 | 9篇 |
1986年 | 11篇 |
1985年 | 13篇 |
1984年 | 8篇 |
1983年 | 16篇 |
1981年 | 7篇 |
1980年 | 11篇 |
1966年 | 7篇 |
1964年 | 7篇 |
1961年 | 9篇 |
1960年 | 6篇 |
1959年 | 8篇 |
1956年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Liu Yang Pengfei Yu Wenyuan Li Fengliang Cao Xin Jin Sheng Xue Xianglong Zhang Tingwei Zhang Mingbo Wu Wenting Wu 《American Institute of Chemical Engineers》2022,68(9):e17760
Hydrogen peroxide (H2O2) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H2O2 is hard to timely decomposed into O2 and H2O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with Co N structure encapsulated Co nanoparticles. Co N graphene shell serves as the active site for the H2O2 decomposition, and Co core further enhance this decomposition. Benefiting from it, the H2O2 decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O2 generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H2O2 with little deep oxidation and protect the process of H2O2 utilization to achieve a safer world. 相似文献
2.
介绍了浙江石油化工有限公司新建的3 Mt/a柴油加氢精制装置,其配套使用中国石化石油化工科学研究院有限公司开发的催化剂级配技术,并实施了可根据原料供应及市场产品需求情况灵活调整切换的2种生产技术方案。1 a的安稳生产运行结果表明:该装置以直馏柴油为主原料,通过分馏塔的馏分切割及其侧线抽出,实现了稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业化应用;在实施以兼产喷气燃料为主的生产技术方案时,通过调整常一线柴油的掺炼量,不仅可以生产含硫量小于10.0 μg/g的精制柴油产品,同时兼产所得到的喷气燃料产品含硫量小于0.5 μg/g,赛波特颜色号值大于30;在实施主产精制柴油组分方案时,通过掺炼质量分数为20%~40%的催化柴油,并使所提炼得到的精制柴油组分含硫量小于6.0 μg/g的前提下,这些精制柴油组分产品既可直接作为满足国Ⅵ柴油产品出厂待售,也可作为柴油调和组分储存待用于产品的进一步优化。 相似文献
3.
Leo H. Chiang Birgit Braun Zhenyu Wang Ivan Castillo 《American Institute of Chemical Engineers》2022,68(6):e17644
In the Industry 4.0 era, the chemical industry is embracing broad adoption of artificial intelligence (AI) and machine learning (ML) methods. This article provides a holistic view of how the industry is transforming digitally towards AI at scale. First, a historical perspective on how the industry used AI to aid humans in better decision-making is shown. Then state-of-the-art AI research addressing industrial needs on reliability and safety, process optimization, supply chain, material discovery, and reaction engineering is highlighted. Finally, a vision of the plant of the future is illustrated with critical components of AI-ready culture, model life cycle management, and renewed role of humans in chemical manufacturing. 相似文献
4.
ABSTRACT Supply chains are becoming increasingly complex, and many companies and researchers are looking to nature for finding solutions. In this paper, we provide a narrative synthesis and systematic review to explore state-of-the-art, and identify key areas for exploration of nature inspired solutions in the supply chain area. We consider strategic, tactical, and operational decisions within supply chains and identify analogies between biological systems and supply chains to create a new research agenda. Our findings show that the majority of the research in nature inspired supply chains from the systemic perspective focuses on closed loop supply chains. In contrast, similar systemic solutions such as industrial symbiosis, circular economy, and industrial ecology have not been explored as frequently. Reducing production waste (industrial symbiosis) in addition to end-of-life product waste (closed loop supply chains), optimising raw material use and extending the life of used resources (circular economy), investigating the interactions between biosphere and technosphere (industrial ecology), and seeking solutions to industrial problems from nature (biomimicry) are all possible paths for reaching a zero-waste economy. These systemic solutions have a considerable impact on the supply chains at the strategic, tactical, and operational levels, which need to be explored to identify efficient and effective solutions. 相似文献
5.
6.
7.
经济发展与生态环境动态良性循环已经成为社会经济发展的重要议题。为实现长江经济带高质量发展,以2007—2018年长江经济带11个省市为样本,采用空间计量和面板门槛模型考察工业集聚与水环境污染之间的关系。研究表明:长江经济带各省市水环境污染具有显著的空间自相关性;长江经济带工业集聚水平和水环境污染表现出先降低后增强的“U”形变化特征,说明工业集聚水平对水环境污染的影响存在一个阈值;长江经济带工业集聚产生的规模效应和结构效应对水环境污染存在显著的双门槛效应,在不同的工业集聚水平下,规模效应和结构效应表现出不同的外部性特征;工业集聚产生的技术溢出效应对水环境污染的影响同样具有显著的双门槛作用;随着各地区工业集聚水平的提高,技术溢出效应对水环境污染的减排作用表现出先强后弱的趋势。 相似文献
8.
通过对唐家河煤矿自然地形条件及外部条件分析,结合井下煤层赋存情况,设计提出三个工业场地选址方案和两个开拓布置方案,通过技术、经济比较,选择陈家湾场地立井开拓方式,减少了矿井初期投资及后期运营费。 相似文献
9.
针对2002年铜地质勘查规范中一般工业指标存在的问题,基于大量实际生产数据,对铜矿床实际采用的边界品位指标、最低工业品位、矿床平均品位、最小可采厚度、夹石剔除厚度、开采技术条件等进行研究,论证了铜矿床的一般工业指标,并首次明确了铜矿床工业指标的适用条件,解决了铜矿床一般工业指标体系应用不一致和指标区间取值主观性的问题。 相似文献
10.
Samira Lotfian Tommy Vikström Andreas Lennartsson Bo Björkman Hesham Ahmed Caisa Samuelsson 《Canadian Metallurgical Quarterly》2019,58(2):164-176
Shredder residue materials are produced after the removal of ferrous and non-ferrous fractions from end-of-life electronic equipment. Despite the high plastic content and metal value in the ash, high percentages of these materials are currently sent to landfills. In this study, the potential of utilising shredder residue material and other plastic-containing materials as reducing agents was studied. Plastic-containing materials were co-injected with coal into a zinc-fuming furnace in Boliden-Rönnskär smelter. The data obtained from the trial, such as the data from the chemical analysis of the slag and the steam production, are discussed. The observations indicate that plastic-containing material can replace up to 1?ton?h?1 of coal without a significant decrease in the zinc reduction rate. 相似文献