全文获取类型
收费全文 | 304篇 |
免费 | 13篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 85篇 |
金属工艺 | 2篇 |
机械仪表 | 18篇 |
建筑科学 | 6篇 |
能源动力 | 8篇 |
轻工业 | 13篇 |
无线电 | 46篇 |
一般工业技术 | 70篇 |
冶金工业 | 21篇 |
自动化技术 | 43篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 9篇 |
2020年 | 3篇 |
2019年 | 8篇 |
2018年 | 9篇 |
2017年 | 9篇 |
2016年 | 14篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 20篇 |
2012年 | 19篇 |
2011年 | 18篇 |
2010年 | 17篇 |
2009年 | 13篇 |
2008年 | 10篇 |
2007年 | 11篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 15篇 |
2003年 | 11篇 |
2002年 | 5篇 |
2001年 | 6篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有317条查询结果,搜索用时 15 毫秒
311.
An algorithm is described for the simulation of the geological processes involved in the formation and evolution of a molasse basin. Variables include continuous subsidence, source-area denudation, formation of cyclothems, and fluviatile meandering 相似文献
312.
Ramos CT Thapa R Lozano K Chipara M Ferrer D Gutierrez JJ 《Journal of nanoscience and nanotechnology》2011,11(5):3965-3969
The grafting of polybutylene oxide onto purified and functionalized carbon nanofibers is reported. Grafting was possible after the insertion of 2-(formyloxy)ethyl 2-bromo-2-methylpropanoate onto the carbon nanofibers. The polymerization of tetrahydrofuran was mediated by copper(I) bromide and 1,1,4,7-pentamethyl diethylenetriamine. The polymer-grafted carbon nanofibers were characterized by Raman spectrsocopy, Transmission Electron Microscopy, and Thermogravimetric Analysis. TEM images of CNF-COOH (A), CNF-PBO (B), completely open tip of CNF-COOH, and coated tip of CNF-PBO (D) are shown in the left panel. The right panel depicts the distribution of bromine (blue), and carbon (red) atoms inside and in the vicinity of CNF-Br (as obtained by Electron Energy Loss Spectroscopy). The bottom shows the actual doped CNF. Preliminary data showed that these modified fibers have potential applications as smart (electrorheological) fluids. 相似文献
313.
314.
Nikolaos Athanasopoulos George Bitsoris Mircea Lazar 《International journal of control》2013,86(8):1681-1693
The problem of construction of controlled invariant polytopic sets with specified complexity, for linear systems subject to linear state and control constraints, is investigated. First, geometric conditions for the enlargement of a polytopic set by adding a new vertex, in order to produce a polytopic set of specified complexity, are established. Next, conditions for such an enlargement of controlled invariant sets to preserve the controlled invariance property are presented. The established theoretical results are used to develop methods for the construction of admissible controlled invariant sets with specified complexity. Two numerical examples show how these results can be used for the computation of monotonic sequences of admissible controlled invariant sets of specified complexity. 相似文献
315.
Emanuela Paduraru Elena-Iuliana Flocea Carlo C. Lazado Ira-Adeline Simionov Mircea Nicoara Alin Ciobica Caterina Faggio Roxana Jijie 《International journal of molecular sciences》2021,22(23)
Environmental contamination from toxic metals and pesticides is an issue of great concern due to their harmful effects to human health and the ecosystems. In this framework, we assessed the adverse effects when aquatic organisms are exposed to toxicants such as deltamethrin (DM) and lead (Pb), alone or in combination, using zebrafish as a model. Moreover, we likewise evaluated the possible protective effect of vitamin C (VC) supplementation against the combined acute toxic effects of the two toxicants. Juvenile zebrafish were exposed to DM (2 μg L−1) and Pb (60 μg L−1) alone and in combination with VC (100 μg L−1) and responses were assessed by quantifying acetylcholinesterase (AChE) activity, lipid peroxidation (MDA), some antioxidant enzyme activities (SOD and GPx), three-dimension locomotion responses and changes of elements concentrations in the zebrafish body. Our results show that VC has mitigative effects against behavioral and biochemical alterations induced by a mixture of contaminants, demonstrating that it can be used as an effective antioxidant. Moreover, the observations in the study demonstrate zebrafish as a promising in vivo model for assessing the neuroprotective actions of bioactive compounds. 相似文献
316.
317.
The aim of this study is to investigate the influence of temperature (20, 25, 30, 35, 40, 45 and 50 °C) and concentration on the evolution of different physical properties (density, viscosity, ultrasonic velocity and surface tension) of honeys. Temperature influences negatively all the physical properties of honey. A good correlation between density, viscosity, ultrasonic velocity and surface tension using linear and polynomial equations was observed. Also a good correlation between density, ultrasonic velocity and surface tension for all the honey samples (R2 = 0.954) was obtained. The correlation between surface tension and viscosity was made using the Pelofsky model and an exponential model; the latter one describes better the correlation between surface tension and viscosity. 相似文献