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   2471篇
  免费   199篇
  国内免费   4篇
电工技术   27篇
综合类   1篇
化学工业   619篇
金属工艺   74篇
机械仪表   76篇
建筑科学   131篇
矿业工程   8篇
能源动力   233篇
轻工业   469篇
水利工程   11篇
石油天然气   13篇
无线电   123篇
一般工业技术   382篇
冶金工业   41篇
原子能技术   59篇
自动化技术   407篇
  2024年   15篇
  2023年   48篇
  2022年   77篇
  2021年   145篇
  2020年   110篇
  2019年   88篇
  2018年   182篇
  2017年   161篇
  2016年   168篇
  2015年   94篇
  2014年   142篇
  2013年   365篇
  2012年   163篇
  2011年   180篇
  2010年   196篇
  2009年   180篇
  2008年   106篇
  2007年   131篇
  2006年   45篇
  2005年   15篇
  2004年   7篇
  2003年   11篇
  2002年   13篇
  2001年   6篇
  2000年   3篇
  1999年   1篇
  1998年   4篇
  1997年   1篇
  1996年   4篇
  1995年   1篇
  1992年   3篇
  1991年   2篇
  1987年   1篇
  1986年   2篇
  1982年   1篇
  1979年   1篇
  1977年   1篇
  1976年   1篇
排序方式: 共有2674条查询结果,搜索用时 875 毫秒
1.
2.
3.
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   
4.
5.
6.
7.
8.
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   
9.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time.  相似文献   
10.
This paper attempts to shed light on the determinants of energy demand in Turkey. Energy demand model is first proposed using the ant colony optimization (ACO) approach. It is multi-agent systems in which the behavior of each ant is inspired by the foraging behavior of real ants to solve optimization problem. ACO energy demand estimation (ACOEDE) model is developed using population, gross domestic product (GDP), import and export. All equations proposed here are linear and quadratic. Quadratic_ACOEDE provided better-fit solution due to fluctuations of the economic indicators. The ACOEDE model plans the energy demand of Turkey until 2025 according to three scenarios. The relative estimation errors of the ACOEDE model are the lowest when they are compared with the Ministry of Energy and Natural Resources (MENR) projection.  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