全文获取类型
收费全文 | 3310篇 |
免费 | 33篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 20篇 |
综合类 | 2篇 |
化学工业 | 501篇 |
金属工艺 | 54篇 |
机械仪表 | 59篇 |
建筑科学 | 119篇 |
矿业工程 | 10篇 |
能源动力 | 47篇 |
轻工业 | 565篇 |
水利工程 | 26篇 |
石油天然气 | 11篇 |
无线电 | 140篇 |
一般工业技术 | 511篇 |
冶金工业 | 835篇 |
原子能技术 | 9篇 |
自动化技术 | 436篇 |
出版年
2024年 | 26篇 |
2023年 | 29篇 |
2022年 | 12篇 |
2021年 | 55篇 |
2020年 | 49篇 |
2019年 | 46篇 |
2018年 | 91篇 |
2017年 | 108篇 |
2016年 | 108篇 |
2015年 | 89篇 |
2014年 | 109篇 |
2013年 | 224篇 |
2012年 | 203篇 |
2011年 | 180篇 |
2010年 | 151篇 |
2009年 | 126篇 |
2008年 | 149篇 |
2007年 | 140篇 |
2006年 | 82篇 |
2005年 | 68篇 |
2004年 | 75篇 |
2003年 | 62篇 |
2002年 | 62篇 |
2001年 | 42篇 |
2000年 | 36篇 |
1999年 | 45篇 |
1998年 | 299篇 |
1997年 | 179篇 |
1996年 | 127篇 |
1995年 | 80篇 |
1994年 | 54篇 |
1993年 | 55篇 |
1992年 | 22篇 |
1991年 | 23篇 |
1990年 | 21篇 |
1989年 | 10篇 |
1988年 | 13篇 |
1987年 | 12篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1977年 | 9篇 |
1976年 | 24篇 |
1975年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
排序方式: 共有3345条查询结果,搜索用时 15 毫秒
1.
2.
3.
A.?Patrascioiu J.?M.?Fernández-Pradas A.?Palla-Papavlu J.?L.?Morenza P.?SerraEmail author 《Microfluidics and nanofluidics》2014,16(1-2):55-63
Laser-based techniques provide excellent means for liquid microprinting, with several advantages over other more conventional printing techniques, such as being nozzle-free (as opposed to inkjet, for instance) or requiring minimal engineering of the liquid properties in the pre-printing stage. In such techniques, the transfer is usually mediated by liquid jets that contact a receiver substrate placed nearby the liquid source, leading to the deposition of a small droplet. The main cause of jetting lies in a laser-generated bubble produced inside the liquid, whose dynamics dictates the evolution of liquid ejection. However, the detailed relationship between the bubble and the jet is not completely understood, as the studies carried out so far have been mostly focused on the jetting dynamics taking place above the liquid free-surface, without access to the liquid interior and therefore to the behavior of the bubble. In this work, we analyze through time-resolved imaging the film-free laser printing of an aqueous solution by simultaneously visualizing both the bubble evolution and the liquid ejection dynamics, thus making possible the correlation between the two phenomena. We find that the pulsating behavior of the bubble leads to successive jetting events with different jet morphologies arising from the particular geometries that the bubble acquires during its evolution. Finally, we find good agreement between our results and those from studies analyzing the dynamics of cavitation bubbles near the free-surface of a liquid through numerical solution of the fluid dynamics equations. 相似文献
4.
M Fernández J Cao MD Vázquez-Illanes JI Ramos-Martínez JA Villamarín 《Canadian Metallurgical Quarterly》1994,33(2):355-363
Phosphofructokinase purified from mantle tissue of the sea mussel Mytilus galloprovincialis, was phosphorylated "in vitro" by the catalytic subunit of cyclic AMP-dependent protein kinase. The incorporation of phosphate gave rise to an activation of the enzyme by increasing its affinity for fructose-6-phosphate, by decreasing its sensitivity to the inhibition by ATP and by enhancing the effect of allosteric activators (5'-AMP and fructose-2,6-bisphosphate). In addition, the effects of phosphorylation on the catalytic activity are pH-dependent. 相似文献
5.
M. Fernández-Delgado M. Reboreda E. Cernadas S. Barro 《Neural computing & applications》2010,19(5):741-754
In the industrial environment, specifically in the automotive industry, an accurate prediction of execution times for each
production task is very useful in order to plan the work and to optimize the human, technical and material resources. In this
paper, we applied several regression neural networks to predict the execution times of the tasks in the production of parts
for plastic injection molds. These molds are used to make a variety of car components in automotive industry. The prediction
is based on the geometric features of the mold parts to be made. The accuracy of the predicted times is high enough to be
used as a tool for the design stage of the mold parts, e.g. guiding the design process in order to get the lowest production
time. 相似文献
6.
7.
A Nadal P Jares M Cazorla PL Fernández X Sanjuan L Hernandez M Pinyol M Aldea C Mallofré J Muntané J Traserra E Campo A Cardesa 《Canadian Metallurgical Quarterly》1997,183(2):156-163
The anti-metastatic effect of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, was investigated in mice bearing B16 melanoma cells. Treatment of BF10 mice implanted with high metastatic B16F10 melanoma cells with a 10 mg/kg dose of Z-100 resulted in the reduction of experimental pulmonary metastasis as compared with that of BF10 mice treated with saline. The number of pulmonary metastatic colonies in BF1 mice (mice implanted with low metastatic B16F1 melanoma cells) was greatly increased after the inoculation of CD4+ CD11b+ CD281+ TCR alphabeta+ type 2 T cells (F10-Th2 cells) derived from BF10 mice, while only a few metastatic colonies were demonstrated in lungs of BF1 mice inoculated with naive CD4+ T cells. However, the numbers of metastatic colonies in BF1 mice were not increased when they were inoculated with the F10-Th2 cell fraction derived from Z-100-treated BF10 mice and the generation of F10-Th2 cells in BF10 mice was effectively suppressed by the Z-100 treatment. These results suggest that Z-100 inhibits pulmonary metastasis of B16 melanoma through the regulation of tumor-associated Th2 cells, which are a key cell in the acceleration of tumor metastasis. 相似文献
8.
9.
Artifact removal in magnetoencephalogram background activity with independent component analysis 总被引:2,自引:0,他引:2
Escudero J Hornero R Abásolo D Fernández A López-Coronado M 《IEEE transactions on bio-medical engineering》2007,54(11):1965-1973
The aim of this study was to assess whether independent component analysis (ICA) could be valuable to remove power line noise, cardiac, and ocular artifacts from magnetoencephalogram (MEG) background activity. The MEGs were recorded from 11 subjects with a 148-channel whole-head magnetometer. We used a statistical criterion to estimate the number of independent components. Then, a robust ICA algorithm decomposed the MEG epochs and several methods were applied to detect those artifacts. The whole process had been previously tested on synthetic data. We found that the line noise components could be easily detected by their frequency spectrum. In addition, the ocular artifacts could be identified by their frequency characteristics and scalp topography. Moreover, the cardiac artifact was better recognized by its skewness value than by its kurtosis one. Finally, the MEG signals were compared before and after artifact rejection to evaluate our method. 相似文献
10.