全文获取类型
收费全文 | 775篇 |
免费 | 14篇 |
国内免费 | 9篇 |
专业分类
电工技术 | 8篇 |
综合类 | 3篇 |
化学工业 | 30篇 |
金属工艺 | 48篇 |
机械仪表 | 15篇 |
建筑科学 | 34篇 |
矿业工程 | 1篇 |
能源动力 | 8篇 |
轻工业 | 43篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 26篇 |
一般工业技术 | 132篇 |
冶金工业 | 382篇 |
原子能技术 | 15篇 |
自动化技术 | 50篇 |
出版年
2022年 | 3篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 12篇 |
2017年 | 8篇 |
2016年 | 12篇 |
2015年 | 7篇 |
2014年 | 17篇 |
2013年 | 51篇 |
2012年 | 16篇 |
2011年 | 22篇 |
2010年 | 20篇 |
2009年 | 32篇 |
2008年 | 16篇 |
2007年 | 26篇 |
2006年 | 17篇 |
2005年 | 15篇 |
2004年 | 17篇 |
2003年 | 15篇 |
2002年 | 18篇 |
2001年 | 10篇 |
2000年 | 12篇 |
1999年 | 21篇 |
1998年 | 104篇 |
1997年 | 59篇 |
1996年 | 38篇 |
1995年 | 32篇 |
1994年 | 19篇 |
1993年 | 24篇 |
1992年 | 7篇 |
1991年 | 11篇 |
1990年 | 14篇 |
1989年 | 6篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 6篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 4篇 |
1978年 | 4篇 |
1977年 | 13篇 |
1976年 | 20篇 |
1975年 | 3篇 |
1974年 | 6篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1967年 | 2篇 |
1966年 | 3篇 |
排序方式: 共有798条查询结果,搜索用时 5 毫秒
1.
2.
3.
A system has been developed for tracking the motion of objects in two dimensions in real-time. The system consists of a conventional CCD camera linked to a transputer-based frame grabber and an array of nine transputers. A parallel moments algorithm is used to extract the co-ordinates of the object's centre of gravity and orientation at field rate, i.e. 60 Hz. Since the position data are made available in real-time—with a small time delay—the system has the potential for inclusion in a feedback loop. Results are presented for tracking the trajectory of a chocolate bar diverted by an air jet. The potential of the system for higher sampling rates—up to 200 Hz—is discussed. 相似文献
4.
The effect on gastric contractility following bilateral microinjection of thyrotropin-releasing hormone (TRH) analog, RX 77368, into the central nucleus of the amygdala was examined in fasted, urethane-anesthetized rats. Extraluminal force transducers were used to measure gastric corpus contractility. Bilateral microinjection of RX 77368 (0.5 microgram, 1.0 microgram, n = 6 each) stimulated gastric contractility for up to 120 min post-injection, P < 0.05. Gastric contractility was not significantly stimulated by microinjection of 0.1 microgram RX 77368, 0.1% bovine serum albumin (BSA) into the central nucleus or RX 77368 (0.5 microgram, 1.0 microgram) into sites adjacent to the central nucleus. Peak responses (1.0 microgram) occurred 40 min post-injection and represented a 16-26-fold increase over basal values. The frequency of gastric contraction waves was attenuated for 0-90 min in rats receiving central amygdaloid microinjection of RX 77368 (0.1, 0.5 or 1.0 microgram) versus rats microinjected with the vehicle or RX 77368 into sites adjacent to the central nuclei. The stimulatory effect of RX 77368 (1.0 microgram) on gastric contractility was abolished by subdiaphragmatic vagotomy. These results indicate that the TRH analog, RX 77368, acts within the central amygdala to vagally stimulate gastric contractility. 相似文献
5.
6.
Xiaoling He Hodgson J.W. 《Intelligent Transportation Systems, IEEE Transactions on》2002,3(4):244-251
For pt.I see ibid., vol.3, no.4, p.235-43 (2002). Hybrid electric vehicle (HEV) simulation is conducted based on the model developed for a parallel HEV built in the University of Tennessee, Knoxville (UT-HEV). The HEV simulation is a parametric analysis of the power control schemes and vehicle performance. Major parameters are evaluated for the vehicle driven under the standard urban and highway driving schedules. The results indicate that current configuration of the UT-HEV NEON has superb capability for battery state of charge (SOC) recovery while meeting the velocity request of the given driving schedules. Recommendations are given from the simulation for optimal performance in light of the HEV power control, capability for SOC recovery through regeneration and regenerative braking, as well as velocity, acceleration and range performance. 相似文献
7.
8.
KO Honikel 《Canadian Metallurgical Quarterly》1998,105(8):327-329
The production of organic (ecological) food of animal origin is done in many ways and uses many different breeds. Therefore a real comparison with conventionally produced food is difficult. From the limited number of published data it appears, that the characteristics of quality of the products, the nutritional, hygienic, sensorial and technological factors, are not very different in both systems of production. In some factors organic food gets better marks, in others the conventionally produced food. The differences are in the production system (process quality) during lifetime of the animals. 相似文献
9.
During studies to develop serum tests of small intestinal permeability, we detected an unidentified disaccharide in HPLC traces of sera from untreated celiacs. This present study aimed to identify the disaccharide and determine whether the presence of the disaccharide in the serum after an oral challenge had potential as a simple screening test for celiac disease. The disaccharide was identified as sucrose by incubation studies of sera with disaccharidases. Twenty untreated celiacs, 15 treated celiacs, and 20 normal or dyspeptic controls were studied for the presence of sucrose in their serum after an oral load (8 g). The results in celiacs were compared with the presence of serum IgA endomysial antibodies. The 10 normal controls were also given a larger sucrose challenge (50 g). Ten of the untreated celiacs and 10 controls had their brush border disaccharidase activities measured. Sucrose eluted in the same position as the unidentified disaccharide in the HPLC trace and the latter could be removed by incubation with sucrase. All untreated celiacs but none of the treated celiacs had sucrose in their serum after the 8-g oral challenge. None of the controls had sucrose in their serum after the 8-g or 50-g challenges. Three untreated celiacs were IgA endomysial antibody negative as were all the treated cases. Brush border sucrase activity was low in untreated celiac disease. The presence of sucrose in the serum after an oral load shows promise as a noninvasive test for celiac disease. 相似文献
10.