全文获取类型
收费全文 | 1913篇 |
免费 | 84篇 |
国内免费 | 15篇 |
专业分类
电工技术 | 24篇 |
综合类 | 4篇 |
化学工业 | 455篇 |
金属工艺 | 85篇 |
机械仪表 | 77篇 |
建筑科学 | 35篇 |
矿业工程 | 2篇 |
能源动力 | 133篇 |
轻工业 | 103篇 |
水利工程 | 12篇 |
石油天然气 | 5篇 |
无线电 | 168篇 |
一般工业技术 | 468篇 |
冶金工业 | 212篇 |
原子能技术 | 13篇 |
自动化技术 | 216篇 |
出版年
2024年 | 6篇 |
2023年 | 38篇 |
2022年 | 68篇 |
2021年 | 94篇 |
2020年 | 88篇 |
2019年 | 74篇 |
2018年 | 114篇 |
2017年 | 98篇 |
2016年 | 101篇 |
2015年 | 54篇 |
2014年 | 84篇 |
2013年 | 167篇 |
2012年 | 80篇 |
2011年 | 115篇 |
2010年 | 97篇 |
2009年 | 89篇 |
2008年 | 82篇 |
2007年 | 82篇 |
2006年 | 42篇 |
2005年 | 36篇 |
2004年 | 27篇 |
2003年 | 32篇 |
2002年 | 21篇 |
2001年 | 20篇 |
2000年 | 20篇 |
1999年 | 15篇 |
1998年 | 27篇 |
1997年 | 30篇 |
1996年 | 24篇 |
1995年 | 23篇 |
1994年 | 18篇 |
1993年 | 14篇 |
1992年 | 12篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1987年 | 16篇 |
1986年 | 15篇 |
1985年 | 8篇 |
1984年 | 16篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1973年 | 2篇 |
1970年 | 2篇 |
排序方式: 共有2012条查询结果,搜索用时 15 毫秒
1.
We considered the magnetohydrodynamic (MHD) free convective flow of an incompressible electrically conducting viscous fluid past an infinite vertical permeable porous plate with a uniform transverse magnetic field, heat source and chemical reaction in a rotating frame taking Hall current effects into account. The momentum equations for the fluid flow during absorbent medium are controlled by the Brinkman model. Through the undisturbed state, both the plate and fluid are in a rigid body rotation by the uniform angular velocity perpendicular to an infinite vertical plate. The perpendicular surface is subject to the homogeneous invariable suction at a right angle to it and the heat on the surface varies about a non-zero unvarying average whereas the warmth of complimentary flow is invariable. The systematic solutions of the velocity, temperature, and concentration distributions are acquired systematically by utilizing the perturbation method. The velocity expressions consist of steady-state and fluctuating situations. It is revealed that the steady part of the velocity field has a three-layer characteristic while the oscillatory part of the fluid field exhibits a multi-layer characteristic. The influence of various governing flow parameters on the velocity, temperature, and concentration are analyzed graphically. We also discuss computational results for the skin friction, Nusselt number, and Sherwood number in the tabular forms. 相似文献
2.
Kumar S. Ganesh Sridhar S. S. Hussain Azham Manikanthan S. V. Padmapriya T. 《Multimedia Tools and Applications》2022,81(7):9091-9109
Multimedia Tools and Applications - Discovering the relevant web services for specific applications in the dynamically changing business world becomes very critical. Researchers have used many... 相似文献
3.
4.
Wireless Personal Communications - In this paper, cooperative communication (CC) assisted cognitive wireless sensor network (CWSN) is presented for monitoring health and activity of an end-user in... 相似文献
5.
6.
Jagadeesh Babu Sriramoju Murthy Muniyappa Navya Rani Marilingaiah Chetana Sabbanahalli Manjunath Shetty Ravi Mudike Chitrabanu C.P Prasanna D. Shivaramu Nagaraju G Kanchugarakoppal S. Rangappa Ananda Kumar C.S Dinesh Rangappa 《Ceramics International》2021,47(7):10314-10321
Application of brown titanium dioxide (TiO2-x) and its modified composite forms in the photocatalytic decomposition of organic pollutants in the environment is a promising way to provide solutions for environmental redemption. Herein, we report the synthesis of effective and stable TiO2-x nanoparticles with g-C3N4, RGO, and multiwalled carbon nanotubes (CNTs) using a simple hydrothermal method. Among all the as-synthesized samples, excellent photocatalytic degradation activity was observed for RGO-TiO2-x nanocomposite with high rate constants of 0.075 min?1, 0.083 min?1 and 0.093 min?1 for methylene blue, rhodamine-B, and rosebengal dyes under UV–Visible light irradiation, respectively. The altered bandgap (1.8 eV) and the large surface area of RGO-TiO2-x nanocomposite impacts on both absorption of visible light and efficiency of photogenerated charge electron (e?)/hole (h+) pair separation. This resulted in enhanced photocatalytic property of carbon-based TiO2-x nanocomposites. A systematic study on the influence of different carbon nanostructures on the photocatalytic activity of brown TiO2-x is carried out. 相似文献
7.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
8.
Agrawal Prachi Ganesh Talari Mohamed Ali Wagdy 《Neural computing & applications》2021,33(11):5989-6008
Neural Computing and Applications - To obtain the optimal set of features in feature selection problems is the most challenging and prominent problem in machine learning. Very few human-related... 相似文献
9.
10.