全文获取类型
收费全文 | 22661篇 |
免费 | 486篇 |
国内免费 | 88篇 |
学科分类
工业技术 | 23235篇 |
出版年
2023年 | 74篇 |
2022年 | 296篇 |
2021年 | 577篇 |
2020年 | 435篇 |
2019年 | 610篇 |
2018年 | 1173篇 |
2017年 | 1215篇 |
2016年 | 1461篇 |
2015年 | 854篇 |
2014年 | 1232篇 |
2013年 | 1637篇 |
2012年 | 1478篇 |
2011年 | 1394篇 |
2010年 | 1347篇 |
2009年 | 1521篇 |
2008年 | 1410篇 |
2007年 | 1344篇 |
2006年 | 1049篇 |
2005年 | 643篇 |
2004年 | 427篇 |
2003年 | 243篇 |
2002年 | 206篇 |
2001年 | 189篇 |
2000年 | 498篇 |
1999年 | 373篇 |
1998年 | 371篇 |
1997年 | 365篇 |
1996年 | 80篇 |
1995年 | 46篇 |
1994年 | 47篇 |
1993年 | 34篇 |
1992年 | 35篇 |
1991年 | 24篇 |
1990年 | 31篇 |
1989年 | 19篇 |
1987年 | 17篇 |
1986年 | 15篇 |
1985年 | 37篇 |
1984年 | 33篇 |
1983年 | 19篇 |
1982年 | 17篇 |
1981年 | 17篇 |
1980年 | 18篇 |
1979年 | 23篇 |
1978年 | 25篇 |
1977年 | 20篇 |
1976年 | 25篇 |
1973年 | 16篇 |
1969年 | 28篇 |
1968年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Journal of Computer and Systems Sciences International - A method for the synthesis of fast finite state machines on programmable logic integrated circuits such as field-programmable gate arrays is... 相似文献
2.
Kuznetsov I. V. Budin O. N. Shchepin A. S. Kalenova M. Yu. Mel’nikova I. M. Saprykin R. V. Al’zhev N. I. 《Inorganic Materials》2022,58(6):651-660
Inorganic Materials - We have studied the effect of annealing on the chemical and physical properties of mineral-like host matrices for immobilization of the rare-earth–actinide fraction from... 相似文献
3.
Matvienko Yu. G. Vasil’ev I. E. Chernov D. V. Kozhevnikov A. V. Mishchenko I. V. 《Russian Journal of Nondestructive Testing》2022,58(5):333-341
Russian Journal of Nondestructive Testing - We study the possibilities of reducing the location error of acoustic emission (AE) sources for cases where AE sources are located near AE receiving... 相似文献
4.
Akintseva A. V. Pereverzev P. P. Prokhorov A. V. Omel’chenko S. V. 《Russian Engineering Research》2022,42(7):721-725
Russian Engineering Research - A system for predicting the machining error for a batch of parts in CNC wheel grinding is described; the system takes the influence of technological variables into... 相似文献
5.
Shalunov A. V. Khmelev V. N. Terent’ev S. A. Nesterov V. A. 《Journal of Engineering Physics and Thermophysics》2022,95(4):909-917
Journal of Engineering Physics and Thermophysics - The possibility of intensifying the drying of materials by noncontact ultrasonic action at a frequency of 22 kHz at sound pressure levels up to... 相似文献
6.
Sofia Melchior Sonia Calligaris Marilena Marino Francesca D’Este Giorgio Honsell Maria Cristina Nicoli Nadia Innocente 《International Journal of Food Science & Technology》2022,57(5):3106-3115
This research aimed at studying the potential use of monoglyceride (MG) structured emulsions (MSEs) as delivery and protective systems for probiotic bacteria in Ricotta cheese. To this purpose, a low-fat commercial Ricotta cheese was added with MSEs formulated with milk, as water phase, and sunflower oil (MSE-SO) or anhydrous milk fat (MSE-AMF), as lipid phase. A commercial whole milk Ricotta cheese (W-RC) was considered as reference. A probiotic Lacticaseibacillus rhamnosus strain was inoculated as free cells in W-RC or embedded into the MSEs and added to the low-fat Ricotta at the same reference fat content. After physico-chemical characterisation, L. rhamnosus viability and sample destructuring behaviour upon in vitro digestion were evaluated. At the end of in vitro digestion, both W-RC and sample containing MSE-SO were unable to protect cells. By contrast, sample with AMF ensured a sufficient probiotic viability, even after 14 days of storage at 4 °C. This result was attributed to system composition and structure. During the gastric phase, the presence of caseins and MG-AMF mixed structures induced the formation of clots, entrapping and protecting cells against the acidic pH of the stomach, as confirmed by confocal micrographs and particle size. During the intestinal phase, cell viability was guaranteed by the formation of mixed micelles promoted by MG. It was demonstrated that microbial cells located near MG structures where they found protection. 相似文献
7.
Seredin P. V. Radam Ali Obaid Goloshchapov D. L. Len’shin A. S. Buylov N. S. Barkov K. A. Nesterov D. N. Mizerov A. M. Timoshnev S. N. Nikitina E. V. Arsentyev I. N. Sharafidinov Sh. Kukushkin S. A. Kasatkin I. A. 《Semiconductors》2022,56(4):253-258
Semiconductors - Abstract—In our work, we carry out a structural-spectroscopic study of AlGaN/GaN epitaxial layers grown by molecular-beam epitaxy with nitrogen-plasma activation on a hybrid... 相似文献
8.
Wireless Personal Communications - Current mobile communications technology relies heavily on efficient design of antennas, where the operational characteristics of the wireless communication... 相似文献
9.
10.
Red’kina G. V. Sergienko A. S. Kuznetsov Yu. I. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(7):1352-1360
Protection of Metals and Physical Chemistry of Surfaces - Abstract—The ability of improving the protective properties of layers formed on zinc in the presence of sodium dodecylphosphonate... 相似文献