全文获取类型
收费全文 | 653篇 |
免费 | 29篇 |
专业分类
电工技术 | 5篇 |
综合类 | 1篇 |
化学工业 | 199篇 |
金属工艺 | 9篇 |
机械仪表 | 16篇 |
建筑科学 | 9篇 |
能源动力 | 5篇 |
轻工业 | 39篇 |
水利工程 | 2篇 |
石油天然气 | 11篇 |
无线电 | 77篇 |
一般工业技术 | 121篇 |
冶金工业 | 86篇 |
自动化技术 | 102篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 11篇 |
2020年 | 9篇 |
2019年 | 15篇 |
2018年 | 10篇 |
2017年 | 14篇 |
2016年 | 17篇 |
2015年 | 19篇 |
2014年 | 22篇 |
2013年 | 17篇 |
2012年 | 26篇 |
2011年 | 39篇 |
2010年 | 29篇 |
2009年 | 19篇 |
2008年 | 44篇 |
2007年 | 39篇 |
2006年 | 37篇 |
2005年 | 24篇 |
2004年 | 19篇 |
2003年 | 20篇 |
2002年 | 18篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 15篇 |
1998年 | 11篇 |
1997年 | 22篇 |
1996年 | 12篇 |
1995年 | 7篇 |
1994年 | 10篇 |
1993年 | 14篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1965年 | 2篇 |
1957年 | 2篇 |
1924年 | 2篇 |
排序方式: 共有682条查询结果,搜索用时 8 毫秒
81.
Peiling Hou Peng Zou Min-Yong Low Eli Chan Hwee-Ling Koh 《Food Additives & Contaminants》2006,23(9):870-875
An analogue of acetildenafil was detected in an extract of pre-mixed bulk powder. To our knowledge, the powder was destined to be encapsulated and sold as a dietary supplement. The structure was identified by NMR, HR-ESI-MS, ESI-MSn and FTIR analyses. Owing to the inclusion of a hydroxyl group in acetildenafil, the detected compound was called 'hydroxyacetildenafil'. With increasing use of dietary supplements marketed for penile erectile dysfunction, the detection of analogues of sexual performance enhancers is important and timely. 相似文献
82.
Eli A. Rubinstein 《The Journal of communication》1975,25(2):194-200
83.
Decisions on organizational arrangements for MIS units comprise location in the organization, rank of responsible executive, organization of MIS implementators, degree of centralization, the user interface, the study group, the steering committee, the data base administrator, the corporate computer staff, and external assistance. Based on a wide-ranging survey of papers in the field of MIS, the authors have formulated guidelines which derive from the impact of organizational decisions on the success or failure or MIS and MIS projects. 相似文献
84.
Modification of nylon 6 by blending with a small amount of a novolac resin has been investigated. Unexpected increased of Tg and tensile modulus and reduction in moisture absorption have been found at levels of novolac incorporation of 1–3 wt %. The small amount of novolac resin also has an effect on the crystallization and nylon 6 crystal structure (α vs. γ form). © 1993 John Wiley & Sons, Inc. 相似文献
85.
The federal health scientist-administrator is centrally involved in the national health program and serves in the interface between science and public policy. In this middleman role there is a role conflict which derives from the dichotomy between his values as a scientist and as an administrator. He is viewed as an expert in the process of federal grantsmanship as well as in the research area for which he has responsibility. It is suggested that he must be willing to accept this role conflict as an attribute of science administration today and work toward a process of integrating the 2 roles. Psychologists and other behavioral scientists should participate in such an effort at integration. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Shows that traumatic responses attached to 1 instance of a concept will impair the identification of the concept even when the traumatized concept is not part of the concept identification task. Such traumatic priming proved detrimental compared with either neutral priming or no priming. Neutral priming proved to facilitate concept identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Examined the reactions of 31 Israeli patients (aged 15–60 yrs) in psychotherapy to the assassination of Prime Minister Yitzhak Rabin using a single-site study. Data were collected during the 1st psychotherapy session following the fatal shooting of the Prime Minister. The 31 vignettes were investigated by 8 clinicians. The patients' reactions were subjected to a qualitative data analysis that yielded high intercoder agreement with regard to 20 codes clustered in 4 content categories: (1) object of reference, (2) perceived threat, (3) personal association, and (4) affect. No apparent relationships between DSM diagnoses and any response patterns were identified, indicating that the Ss might have responded with grief reactions that transcended diagnostic nosologies. Findings indicate, however, that Ss with a history of paternal child abuse were significantly more likely to respond in a unique way. These Ss often identified with members of the surviving family or with the assassin rather than with the slain leader; explored anxieties about the looming dangers emanating from the Israeli extreme right; and displayed feelings of revenge, disgust, or satisfaction with this figurative patricide. These findings are discussed from a psychodynamic perspective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
89.
The subject of sintering (sometimes termed coarsening) has received considerable attention since the late 1960s, and a review [1] appeared in this journal in 1975. Significant progress has been made since then, in particular, with regard to the mechanisms and kinetics of sintering and measurement techniques. With these advances it is now possible to utilize the understanding gained for the design of reactors undergoing catalyst sintering. In fact, a few attempts have already been made. 相似文献
90.
Karayiannis NB Xiong Y Frost JD Wise MS Mizrahi EM 《IEEE transactions on bio-medical engineering》2005,52(6):1065-1077
This paper introduces a methodology for the development of robust motion trackers for video based on block motion models. According to this methodology, the motion of a site between two successive frames is estimated by minimizing an error function defined in terms of the intensities at these frames. The proposed methodology is used to develop robust motion trackers that rely on fractional block motion models. The motion trackers developed in this paper are utilized to extract motor activity signals from video recordings of neonatal seizures. The experimental results reveal that the proposed motion trackers are more accurate and reliable than existing motion tracking methods relying on pure translation and affine block motion models. 相似文献