首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2125篇
  免费   66篇
  国内免费   4篇
电工技术   36篇
综合类   1篇
化学工业   418篇
金属工艺   137篇
机械仪表   98篇
建筑科学   28篇
矿业工程   12篇
能源动力   30篇
轻工业   20篇
水利工程   25篇
石油天然气   112篇
无线电   176篇
一般工业技术   580篇
冶金工业   212篇
原子能技术   127篇
自动化技术   183篇
  2023年   19篇
  2022年   52篇
  2021年   79篇
  2020年   35篇
  2019年   60篇
  2018年   94篇
  2017年   70篇
  2016年   88篇
  2015年   59篇
  2014年   64篇
  2013年   105篇
  2012年   104篇
  2011年   111篇
  2010年   77篇
  2009年   102篇
  2008年   94篇
  2007年   79篇
  2006年   72篇
  2005年   59篇
  2004年   50篇
  2003年   48篇
  2002年   52篇
  2001年   42篇
  2000年   32篇
  1999年   32篇
  1998年   25篇
  1997年   27篇
  1996年   22篇
  1995年   19篇
  1994年   23篇
  1993年   14篇
  1992年   15篇
  1991年   14篇
  1990年   13篇
  1989年   14篇
  1987年   13篇
  1986年   13篇
  1985年   16篇
  1982年   12篇
  1981年   14篇
  1979年   13篇
  1978年   19篇
  1977年   23篇
  1976年   17篇
  1974年   12篇
  1973年   13篇
  1972年   19篇
  1971年   13篇
  1970年   15篇
  1967年   11篇
排序方式: 共有2195条查询结果,搜索用时 15 毫秒
1.
2.
This article is devoted to work done in 2002–2006 as part of the unified project Reabilitatsiya to rehabilitate radiation hazardous objects and sections of the radioactively contaminated territory of the Russian Science Center Kurchatov Institute. The main objects of the rehabilitation work were old storage sites built for radioactive wastes on the territory of the Institute when military and civilian nuclear technologies were under development. The structural features of the storage sites, including the volumes and characteristics of the wastes stored, are presented. The salient aspects of the disposal sites, taken into account during the rehabilitation work, are discussed. The organization of the rehabilitation operations and the sequence in which they are performed, the special features of the technical design solutions used, the technological methods, and ways for conducting the work are described. __________ Translated from Atomnaya énergiya, Vol. 102, No. 5, pp. 300–306, May, 2007.  相似文献   
3.
A diagnostic array has been developed for studying the operating modes of the divertor in the ITER tokamak-reactor using the Thomson scattering technique. The aim of this study is to measure the spatial profiles of the electron temperature and density. The structure of the diagnostic setup was selected on the basis of a classical diagnostic geometry and the high-resolution LIDAR system, which provide access to different regions of the divertor plasma. A severe radiation environment, limited access to the plasma in the ITER divertor, and a high-dust environment (the divertor plate erosion material) in the divertor volume pose many problems for performing diagnostics under unique conditions having no analogs in the tokamaks that are now in operation. Different methods for protecting optical surfaces from plasma-enriched deposition are proposed and analyzed. The efficiency of these methods has been demonstrated in bench tests. The concept of laser and detector systems and diffraction polychromators capable of operating at different electron temperatures with a lower limit of 1 eV, has been justified and approved.  相似文献   
4.
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 8, pp. 29–30, August, 1992.  相似文献   
5.
In the paper, the problem of existence of the minimal involutive monomial basis is considered for different involutive divisions. The existence criterion is obtained in the form of a constructivity property. In the paper, new examples of constructive and nonconstructive (> σ)-divisions are presented.  相似文献   
6.
A population balance method in which continuum and discrete phases are integrated is developed to simulate the evolution of polydisperse population of bubbles in a turbulent pipeline flow. The investigation is focused on the effect of the coalescence efficiency on this evolution. A dilute system of bubbles under microgravity conditions is considered. It is found that if the initial coalescence efficiency is low, a slight increase produces a significant effect on the bubble coalescence rate, and thus on the evolution of the population. If, however, the initial coalescence efficiency is high, its increase results in a marginal effect on the way the population evolves. The results of simulations are validated against experimental data on the population mean.  相似文献   
7.
8.
Conclusions We investigated volatilization in isothermal conditions of solid solutions of oxides of calcium and yttrium in ZrO2.The calcium oxide is intensely sublimited from the solid solution of zirconium dioxide, stabilized with CaO at 2000–2100°C. However, during soaking and rapid cooling, destabilization does not occur, even during sublimation of 70–75% CaO. With rise in temperature to 2400–2500°C and a 4 h soak, only 0.5% CaO is preserved in the solid solution, which leads to destabilization and conversion of a large part of the cubic form of ZrO2 with calcium oxide by fusion, we note sublimation of part of the CaO, and the remaining quantity (3%) is adequate for complete conversion of the zirconia into the stable cubic form.Volatilization of the stabilizing additive occurs in the form of YO at substantially higher temperatures than volatilization of the calcium oxide from the solid solution of zirconium dioxide, stabilized with yttrium oxide. Simultaneously with this we note volatilization of zirconium dioxide in the form of ZrO and ZrO2.For the use of zirconium dioxide at elevated service temperatures, we would recommend yttrium oxide as a stabilizing additive.Translated from Ogneupory, No. 1, pp. 49–52, January, 1968.  相似文献   
9.
Conclusions A technique for the reaction sintering of a new refractory made of 82–83% boron nitride and 17–18% graphite has been developed.The refractory possesses high specific resistance up to 1500–1800°, a low coefficient of thermal expansion, a moderative evaporation rate in a vacuum, satisfactory strength and machinability, as well as high resistance to cryolite-aluminum melts, borate, chloride and also silicide and boron-silicon alloy melts (at between 900 and 2000°).  相似文献   
10.
Thin and thick YBCO Films have been grown by Aerosol Assisted as well as by thermal MOCVD. The Aerosol Assisted MOCVD technique allows the growth of YBCO films from a single liquid source at deposition rates of up to 10m/h.Transport measurements (I-V) on etched microbridges using a single pulse technique have been performed. The angular magnetic field dependence Jc() of the critical current density from Tc down to 50 K has been measured. Transport properties are reported and discussed with respect to the microstructural features as determined by X-ray diffraction and electron microscopy.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号