全文获取类型
收费全文 | 1203篇 |
免费 | 68篇 |
专业分类
电工技术 | 19篇 |
综合类 | 4篇 |
化学工业 | 347篇 |
金属工艺 | 18篇 |
机械仪表 | 9篇 |
建筑科学 | 118篇 |
矿业工程 | 3篇 |
能源动力 | 33篇 |
轻工业 | 84篇 |
水利工程 | 5篇 |
石油天然气 | 2篇 |
无线电 | 94篇 |
一般工业技术 | 215篇 |
冶金工业 | 50篇 |
原子能技术 | 5篇 |
自动化技术 | 265篇 |
出版年
2024年 | 4篇 |
2023年 | 17篇 |
2022年 | 24篇 |
2021年 | 36篇 |
2020年 | 29篇 |
2019年 | 27篇 |
2018年 | 29篇 |
2017年 | 29篇 |
2016年 | 55篇 |
2015年 | 41篇 |
2014年 | 46篇 |
2013年 | 69篇 |
2012年 | 70篇 |
2011年 | 92篇 |
2010年 | 74篇 |
2009年 | 75篇 |
2008年 | 68篇 |
2007年 | 67篇 |
2006年 | 67篇 |
2005年 | 42篇 |
2004年 | 46篇 |
2003年 | 30篇 |
2002年 | 30篇 |
2001年 | 16篇 |
2000年 | 17篇 |
1999年 | 16篇 |
1998年 | 18篇 |
1997年 | 23篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1992年 | 10篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1978年 | 3篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1970年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有1271条查询结果,搜索用时 31 毫秒
111.
112.
113.
Ronald M. Meixner Dominik Cibis Klaus Krueger Holger Goebel 《Microsystem Technologies》2008,14(8):1137-1142
This paper presents a detailed study on the properties of different polymer inks based on poly(3,4ethylenedioxythiophene)/polystyrenesulfonate
regarding their processability in an experimental piezo driven drop-on-demand (DoD) micro-feeding system. Based on the rheological
properties of the used inks and the mechanical properties of the printing system characteristic values are derived which allow
to predict the processability of polymer inks in a given printing system. Beside the printability the influence of different
polymer inks on the electrical characteristics of printed organic field effect transistors is investigated. 相似文献
114.
The total energy influx for a typical radiofrequency process plasma has been measured by means of a simple thermal probe. The procedure is based on the measurement of temporal slope of the substrate temperature during the plasma process. A substrate dummy which is thermally isolated and inserted into the plasma at substrate position served as thermal probe. It can be moved in vertical and horizontal directions in order to measure the different energy influxes and their topology in the reactor vessel. The knowledge of the spatial distribution is important for coating or sputtering processes.Different contributions to the total energy influx can be identified by different orientation of the thermal probe. If the thermal probe is orientated to the rf-electrode (“down”) the energy influx is much higher than in the opposite direction. This difference can be explained by an additional influx due to the secondary electron emission from the powered rf-electrode. 相似文献
115.
Holger Martin 《化学工程与技术》1990,13(1):237-241
The well-known formulae for efficiency and mean temperature difference of a heat exchanger as functions of its numbers of transfer units, or dimensionless lengths, can be written in a more compact form by introducing the auxiliary function φ(x) = x/(1 – e?x). The resulting new formulae show a number of advantages: They are shorter, easier to memorize, and in many cases the limiting values can be seen more directly. They may therefore contribute to easier and faster heat exchanger design, and to reduced probability of errors in the relevant calculations. 相似文献
116.
In recent years, biocompatible polyethers with multi‐aminofunctionality have been used for a variety of applications in different fields. Both established and recently developed synthesis strategies for such polymers and applications as stimuli‐responsive materials, non‐viral vectors, shell crosslinked micelles and for surface functionalization are reviewed. The intriguing potential of such materials is due to both polyether and polyamine components and can thus be readily tuned by the copolymer microstructure and composition. © 2013 Society of Chemical Industry 相似文献
117.
118.
In previous experiments of Girgsdies (1982), eight sterile (ste) mutants of Schizosaccharomyces pombe did not sporulate when fused with h+ or h? protoplasts. We succeeded in achieving sporulation with these mutants. Two hitherto unknown ste genes, ste7 and ste8, were found. 相似文献
119.
Qi Zhou Tijana Perovic Ines Fechner Lowell T. Edgar Peter R. Hoskins Holger Gerhardt Timm Krüger Miguel O. Bernabeu 《Journal of the Royal Society Interface》2021,18(179)
Sprouting angiogenesis is an essential vascularization mechanism consisting of sprouting and remodelling. The remodelling phase is driven by rearrangements of endothelial cells (ECs) within the post-sprouting vascular plexus. Prior work has uncovered how ECs polarize and migrate in response to flow-induced wall shear stress (WSS). However, the question of how the presence of erythrocytes (widely known as red blood cells (RBCs)) and their impact on haemodynamics affect vascular remodelling remains unanswered. Here, we devise a computational framework to model cellular blood flow in developmental mouse retina. We demonstrate a previously unreported highly heterogeneous distribution of RBCs in primitive vasculature. Furthermore, we report a strong association between vessel regression and RBC hypoperfusion, and identify plasma skimming as the driving mechanism. Live imaging in a developmental zebrafish model confirms this association. Taken together, our results indicate that RBC dynamics are fundamental to establishing the regional WSS differences driving vascular remodelling via their ability to modulate effective viscosity. 相似文献
120.