全文获取类型
收费全文 | 603732篇 |
免费 | 4767篇 |
国内免费 | 1962篇 |
专业分类
电工技术 | 10855篇 |
综合类 | 519篇 |
化学工业 | 89441篇 |
金属工艺 | 22367篇 |
机械仪表 | 18784篇 |
建筑科学 | 13760篇 |
矿业工程 | 2634篇 |
能源动力 | 16994篇 |
轻工业 | 51098篇 |
水利工程 | 5905篇 |
石油天然气 | 9542篇 |
武器工业 | 23篇 |
无线电 | 74093篇 |
一般工业技术 | 117427篇 |
冶金工业 | 113233篇 |
原子能技术 | 11681篇 |
自动化技术 | 52105篇 |
出版年
2022年 | 3375篇 |
2021年 | 5456篇 |
2020年 | 4428篇 |
2019年 | 5526篇 |
2018年 | 8343篇 |
2017年 | 8356篇 |
2016年 | 9132篇 |
2015年 | 5947篇 |
2014年 | 9822篇 |
2013年 | 29134篇 |
2012年 | 16268篇 |
2011年 | 22331篇 |
2010年 | 17632篇 |
2009年 | 19902篇 |
2008年 | 20527篇 |
2007年 | 20327篇 |
2006年 | 18395篇 |
2005年 | 16578篇 |
2004年 | 15863篇 |
2003年 | 15691篇 |
2002年 | 14722篇 |
2001年 | 14919篇 |
2000年 | 13831篇 |
1999年 | 14737篇 |
1998年 | 36936篇 |
1997年 | 25640篇 |
1996年 | 19528篇 |
1995年 | 14642篇 |
1994年 | 12807篇 |
1993年 | 12804篇 |
1992年 | 9110篇 |
1991年 | 8638篇 |
1990年 | 8484篇 |
1989年 | 8002篇 |
1988年 | 7695篇 |
1987年 | 6537篇 |
1986年 | 6331篇 |
1985年 | 7382篇 |
1984年 | 6728篇 |
1983年 | 6103篇 |
1982年 | 5616篇 |
1981年 | 5725篇 |
1980年 | 5334篇 |
1979年 | 5067篇 |
1978年 | 4914篇 |
1977年 | 5639篇 |
1976年 | 7237篇 |
1975年 | 4246篇 |
1974年 | 3984篇 |
1973年 | 4121篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
Silicon - The formation of alkali-activated binders from industrial end products and landfill materials attracts considerable interest in construction technology since it diminishes the waste... 相似文献
182.
Gobinath V. K. Rajasekar R. Santhosh S. Moganapriya C. Sri A. Manju Jaganathan S. K. 《SILICON》2022,14(15):9773-9788
Silicon - Antireflection coatings (ARCs) have become one of the key techniques for mass production of Si solar cells. They are generally performed by vacuum processes such as thermal evaporation,... 相似文献
183.
Recent Advances in CNT-based FET Transistor Biosensors to Detect Biomarkers of Clinical Significance
Yupapin Preecha Mahesha C. R. Fouladi Hadis Hamidi Abdolsamad Farmani Ali 《SILICON》2022,14(15):9275-9281
Silicon - The development of advanced materials has attracted interest for promising novel applications in biosensing and realm of nanophotonics. This interest in nanoelectronics, and... 相似文献
184.
Metal Science and Heat Treatment - Results of a study of transportation of chromium and iron by iodine at various temperatures of diffusion chromizing of armco iron are presented. The phase... 相似文献
185.
Konopatskii A. S. Dubinskii S. M. Zhukova Yu. S. Inaekyan K. Brailovskii V. Prokoshkin S. D. Filonov M. R. 《Metal Science and Heat Treatment》2019,61(5-6):333-339
Metal Science and Heat Treatment - Ti – Zr-based alloys with a high zirconium content prepared by vacuum-arc remelting with nonconsumable tungsten electrode are studied. The optimum number of... 相似文献
186.
Ponraj N. Vijay Azhagurajan A. Vettivel S. C. Sahaya Shajan X. Nabhiraj P. Y. Haiterlenin A. 《Metal Science and Heat Treatment》2019,60(9-10):611-615
Metal Science and Heat Treatment - Composites obtained by powder metallurgy from a mixture of copper powders and graphene nanosheets are studied. The response surface methodology is used to design... 相似文献
187.
Hoseinie S. H. Ataei M. Mikaeil R. 《Bulletin of Engineering Geology and the Environment》2019,78(3):1443-1449
Bulletin of Engineering Geology and the Environment - Quantifying the rock microfabric is one of the most important research interests and challenges in the field of rock drilling and excavation.... 相似文献
188.
Comparative Cytotoxicity of Artemisinin and Cisplatin and Their Interactions with Chlorogenic Acids in MCF7 Breast Cancer Cells 下载免费PDF全文
Dr. John O. Suberu Dr. Isolda Romero‐Canelón Dr. Neil Sullivan Prof. Alexei A. Lapkin Dr. Guy C. Barker 《ChemMedChem》2014,9(12):2791-2797
In parts of Africa and Asia, self‐medication with a hot water infusion of Artemisia annua (Artemisia tea) is a common practice for a number of ailments including malaria and cancer. In our earlier work, such an extract showed better potency than artemisinin alone against both chloroquine‐sensitive and ‐resistant parasites. In this study, in vitro tests of the infusion in MCF7 cells showed high IC50 values (>200 μM ). The combination of artemisinin and 3‐caffeoylquinic acid (3CA), two major components in the extract, was strongly antagonistic and gave a near total loss of cytotoxicity for artemisinin. We observed that the interaction of 3CAs with another cytotoxic compound, cisplatin, showed potentiation of activity by 2.5‐fold. The chelation of cellular iron by 3CA is hypothesized as a possible explanation for the loss of artemisinin activity. 相似文献
189.
S. A. Selishcheva M. Yu. Lebedev S. I. Reshetnikov L. I. Trusov V. A. Yakovlev 《Catalysis in Industry》2014,6(1):60-66
To establish principal regularities of the hydrotreatment of rapeseed oil fatty acid triglycerides (FATs), the kinetics of this process has been studied at temperatures of 300–380°C, contact times of 0.38–0.10 h, and a hydrogen pressure of 1.0 MPa in a flow fixed-bed reactor. The process is performed over nonsulfided nickel catalysts, which are of great practical interest for the production of green diesel. The kinetic scheme of the process with consideration for target products (alkanes) and all oxygen-containing by-products has been proposed. The quantitative estimate, which enables the prediction of the composition of products for other process conditions, has been obtained for the principal paths of the hydrotreatment of rapeseed oil FATs. 相似文献
190.
I.?I.?SalakhovEmail author A.?Z.?Batyrshin S.?A.?Sergeev G.?D.?Bukatov A.?A.?Barabanov A.?G.?Sakhabutdinov V.?A.?Zakharov Kh.?Kh.?Gilmanov 《Catalysis in Industry》2014,6(3):198-201
A comparative study of propylene polymerization in liquid monomer is performed under laboratory conditions using the IK-8-21 Ti-Mg catalyst designed at the Boreskov Institute of Catalysis and imported industrial catalysts (conditionally labeled TMC-1, -2, and -3). The activity and stereospecificity of the catalysts are estimated along with properties of the resulting polypropylene (granular composition and physicomechanical characteristics). It is shown that the IK-8-21 catalyst is not inferior to imported counterparts in terms of catalytic properties in the synthesis of polypropylene. The polypropylene powder formed on IK-8-21 is homogeneous and has good morphology. The physicomechanical characteristics of polypropylene synthesized on the domestic IK-8-21 catalyst are similar to those for polypropylene prepared with the imported TMK-1 catalyst. 相似文献