全文获取类型
收费全文 | 3233篇 |
免费 | 198篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 37篇 |
化学工业 | 840篇 |
金属工艺 | 126篇 |
机械仪表 | 84篇 |
建筑科学 | 81篇 |
矿业工程 | 15篇 |
能源动力 | 127篇 |
轻工业 | 542篇 |
水利工程 | 25篇 |
石油天然气 | 9篇 |
无线电 | 169篇 |
一般工业技术 | 740篇 |
冶金工业 | 43篇 |
原子能技术 | 46篇 |
自动化技术 | 549篇 |
出版年
2024年 | 12篇 |
2023年 | 40篇 |
2022年 | 34篇 |
2021年 | 97篇 |
2020年 | 84篇 |
2019年 | 109篇 |
2018年 | 171篇 |
2017年 | 153篇 |
2016年 | 154篇 |
2015年 | 149篇 |
2014年 | 190篇 |
2013年 | 389篇 |
2012年 | 195篇 |
2011年 | 242篇 |
2010年 | 242篇 |
2009年 | 186篇 |
2008年 | 113篇 |
2007年 | 86篇 |
2006年 | 50篇 |
2005年 | 14篇 |
2004年 | 27篇 |
2003年 | 26篇 |
2002年 | 34篇 |
2001年 | 30篇 |
2000年 | 36篇 |
1999年 | 22篇 |
1998年 | 20篇 |
1997年 | 20篇 |
1996年 | 18篇 |
1995年 | 21篇 |
1994年 | 17篇 |
1993年 | 25篇 |
1992年 | 20篇 |
1991年 | 13篇 |
1990年 | 12篇 |
1989年 | 14篇 |
1988年 | 12篇 |
1985年 | 19篇 |
1984年 | 24篇 |
1983年 | 20篇 |
1982年 | 21篇 |
1981年 | 37篇 |
1980年 | 26篇 |
1979年 | 23篇 |
1978年 | 24篇 |
1977年 | 21篇 |
1976年 | 33篇 |
1975年 | 23篇 |
1974年 | 16篇 |
1973年 | 22篇 |
排序方式: 共有3433条查询结果,搜索用时 0 毫秒
951.
952.
953.
Janavi Elmira Mansourzadeh Mohammad Javad Samandar Ali Eshtehardi Mojgan 《Scientometrics》2020,124(3):2229-2249
Scientometrics - This paper introduces the use of co-nomination as a method to map research fields by directly accessing their knowledge networks organised around exchange relationships of... 相似文献
954.
Z. Murčinková K. Vasilko J. Živčák J. Murčinko 《Materialwissenschaft und Werkstofftechnik》2020,51(8):1170-1179
This study deals with the concept of increasing energy efficiency by means of decreasing the energetic losses by using advanced composite machine tool components and interfaces characterized by low friction, and high wear resistance. Moreover, this study provides experimental results of damping property measurements and characteristic time domain curves of the fibre, particle, and sandwich composites, underlining the advantages of such composite types in terms of dynamic loading. Furthermore, it provides an analysis on the usage of thin films (coatings) and energy consumption in terms of cutting conditions. The study analyses the cutting tool geometry and shape of cutting edge that positively affect the cutting forces and chip flow direction, and avoid the energy-intensive restricted cutting effect. Respecting the results of the analyses of mentioned effects contributes to increasing the energy efficiency of the machine tool-cutting tool-workpiece system. 相似文献
955.
Clean Technologies and Environmental Policy - The paper shows the process of the development of the sustainable energy action plan (SEAP) for the city of Zagreb and analysis of the interaction... 相似文献
956.
Ničković Dejan Lebeltel Olivier Maler Oded Ferrère Thomas Ulus Dogan 《International Journal on Software Tools for Technology Transfer (STTT)》2020,22(6):741-758
International Journal on Software Tools for Technology Transfer - We introduce in this paper $$text {AMT} ; 2.0$$ , a tool for qualitative and quantitative analysis of hybrid continuous and... 相似文献
957.
Chalupa Marek Strejček Jan Vitovská Martina 《International Journal on Software Tools for Technology Transfer (STTT)》2020,22(2):115-133
International Journal on Software Tools for Technology Transfer - We present an improved version of the memory safety verification approach implemented in Symbiotic 5, the winner of the MemSafety... 相似文献
958.
Branko Matović Biljana Babić Dušan Bučevac Maria Čebela Vesna Maksimović Jelena Pantić Miroslav Miljković 《Ceramics International》2013,39(1):719-723
Hafnium carbide powder was synthesized by sol–gel polycondensation of hafnium chloride with citric acid. The starting materials were dissolved in water and mixed homogeneously on a hot plate until precursor gel was formed. Pyrolysis of this gel resulted in monoclinic hafnia which after subsequent heat treatment transformed into hafnium carbide. The obtained materials were analyzed by means of X-ray diffraction and scanning electron microscopy. The results showed that the obtained carbide powders were composed of nearly equiaxed particles with narrow size distribution. Characterization by nitrogen adsorption showed that the obtained powders were micro- and mesoporous materials with high specific surface area. 相似文献
959.
Ana Mraković Jovan Blanuša Darinka Primc Marija Perović Zvonko Jagličić Vladan Kusigerski Vojislav Spasojević 《Ceramics International》2013,39(4):3771-3777
A modified solid-state combustion route was developed for the preparation of nanocrystalline manganite La0.7Ca0.3MnO3 in a single-step process, using metal nitrates and glucose/KNO3 redox mixture. The obtained sample was found to crystallize within O′ type of orthorhombic perovskite structure (space group Pnma), without the presence of other structural phases or impurities. Nanoparticles are found to have particle size in the range 12–35 nm, and to be highly crystalline without the presence of amorphous surface layer. Magnetic measurements show that nanoparticles display bulk-like magnetic properties, with ferromagnetic phase transition at 125 K and the absence of superparamagnetic or spin-glass behavior. 相似文献
960.
Monika Michálková Zoltán Lenčéš Martin Michálek Peter Kocher Jakob Kuebler Pavol Šajgalík 《Journal of the European Ceramic Society》2013,33(13-14):2429-2434
In order to find out the influence of sintering additives on the electrical conductivity of Si3N4-based ceramics composites with dispersed carbon nano-fibers (CNFs) two different mixtures of sintering additives were tested – Al2O3/Yb2O3 and MgSiN2/Yb2O3, respectively. Optimization of hot-pressing conditions was performed for each mixture. The results show that the electrical conductivity can be effectively increased up to 1315 S/m by replacement of traditional sintering aid – alumina, with magnesium silicon nitride, while the mechanical properties remained on the same level. Other advantages of using MgSiN2 instead of alumina are the preservation of higher amounts of CNFs in the ceramic composite and lower densification temperature (1500 °C) compared to samples sintered with alumina-based sintering aids (1550 °C). 相似文献