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   4465篇
  免费   297篇
  国内免费   6篇
电工技术   56篇
综合类   1篇
化学工业   1063篇
金属工艺   107篇
机械仪表   144篇
建筑科学   222篇
矿业工程   8篇
能源动力   375篇
轻工业   836篇
水利工程   26篇
石油天然气   17篇
无线电   231篇
一般工业技术   782篇
冶金工业   108篇
原子能技术   66篇
自动化技术   726篇
  2024年   24篇
  2023年   69篇
  2022年   140篇
  2021年   218篇
  2020年   182篇
  2019年   169篇
  2018年   271篇
  2017年   240篇
  2016年   282篇
  2015年   158篇
  2014年   233篇
  2013年   538篇
  2012年   281篇
  2011年   342篇
  2010年   296篇
  2009年   308篇
  2008年   225篇
  2007年   232篇
  2006年   115篇
  2005年   83篇
  2004年   66篇
  2003年   55篇
  2002年   54篇
  2001年   18篇
  2000年   19篇
  1999年   25篇
  1998年   27篇
  1997年   12篇
  1996年   20篇
  1995年   6篇
  1994年   4篇
  1993年   5篇
  1992年   5篇
  1991年   6篇
  1990年   4篇
  1989年   4篇
  1988年   4篇
  1987年   4篇
  1986年   4篇
  1985年   2篇
  1984年   6篇
  1981年   2篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1970年   1篇
  1961年   1篇
  1957年   1篇
排序方式: 共有4768条查询结果,搜索用时 9 毫秒
1.
2.
3.
4.
Journal of Communications Technology and Electronics - This paper implements mathematically rigorous extended trial function algorithm to address cubic–quartic optical solitons in...  相似文献   
5.
Alkyd resins are generally used in the production of printing inks. All industries look for alternative raw materials in the production of ink with the growing inclination toward using natural products. Resins forming the vehicle of the ink to be obtained from natural resources will provide benefits for the environment, nature, and living creatures. The aim of the study was to promote the use of natural resin in the ink system. Natural Pinus pinaster resin was added into vegetable and mineral oil-based solvents in pure form with alkyd resin in different amounts and ink varnishes of different combinations were prepared. Then, printing inks were produced from these varnishes in pure and hybrid form. Following the assessment of the rheological properties of the inks prepared, printing tests were conducted to assess the printing quality parameters. Ideal mixing ratios of the natural resins in the ink were determined for printability. The environmental importance and advantages of the use of natural resins were discussed. Recommendations were given in line with the results to encourage widespread use of natural resins in near future.  相似文献   
6.
7.
8.
9.
In this study, the relationship between stunning techniques and protein oxidation which are accepted as the main cause of food spoilage was investigated. For this purpose, the antioxidant status, in vivo myofibrillary protein (MP) oxidation and sensitivity, and postmortem oxidation (inducted with hydroxyl radical system) of rainbow trout (Oncorhynchus mykiss) fillets killed by hitting to head (T1), neck crushing (T2), and convulsion (T3) methods, were investigated. Statistically significant differences (p < .05) were found among all parameters examined and it was observed that the most stressing technique was the convulsion method. It was determined that in protein profiles myosin were influenced too much from stunning technique and in actin observed oxidation-induced reductions. Reductions in S-S and S-H were also found to be increased in carbonyl concentrations, but the most effective values in both processes were determined by the convulsive technique. Our results show that short-term stunning techniques (hitting to head, neck crushing) give better meat quality results in terms of O. mykiss welfare and low MP oxidation rates. In general, we can say that T3 group fillets are more sensitive to oxidative damage, while T1 and T2 groups give better results in maintaining meat quality with low MP oxidation rates.  相似文献   
10.
In order to observe the transport ability of peritoneum to small molecular substances, peritoneal equilibration test (PET) was performed in 52 CAPD patients. By analysing the relationship between peritoneal transport function and dialysis adequacy, we found the average urea KT/V and Cr were significantly lower in high and low transport groups (n = 6 and n = 2) than in high average and low average groups (n = 35 and n = 9). According to the results of PET, we adjusted the dialysis program of 11 patients and the dialysis adequacy was markedly improved. We concluded that PET was helpful for selecting and adjusting CAPD program, and discussed some questions which should be payed more attention in PET operation.  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