全文获取类型
收费全文 | 1874篇 |
免费 | 135篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 49篇 |
综合类 | 2篇 |
化学工业 | 362篇 |
金属工艺 | 39篇 |
机械仪表 | 24篇 |
建筑科学 | 65篇 |
矿业工程 | 2篇 |
能源动力 | 61篇 |
轻工业 | 154篇 |
水利工程 | 10篇 |
石油天然气 | 3篇 |
无线电 | 196篇 |
一般工业技术 | 419篇 |
冶金工业 | 365篇 |
原子能技术 | 10篇 |
自动化技术 | 251篇 |
出版年
2023年 | 37篇 |
2022年 | 47篇 |
2021年 | 77篇 |
2020年 | 56篇 |
2019年 | 57篇 |
2018年 | 54篇 |
2017年 | 38篇 |
2016年 | 77篇 |
2015年 | 66篇 |
2014年 | 69篇 |
2013年 | 106篇 |
2012年 | 143篇 |
2011年 | 176篇 |
2010年 | 122篇 |
2009年 | 93篇 |
2008年 | 111篇 |
2007年 | 105篇 |
2006年 | 85篇 |
2005年 | 58篇 |
2004年 | 50篇 |
2003年 | 41篇 |
2002年 | 34篇 |
2001年 | 18篇 |
2000年 | 22篇 |
1999年 | 20篇 |
1998年 | 35篇 |
1997年 | 37篇 |
1996年 | 22篇 |
1995年 | 22篇 |
1994年 | 9篇 |
1993年 | 12篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1969年 | 5篇 |
1963年 | 2篇 |
排序方式: 共有2012条查询结果,搜索用时 15 毫秒
91.
92.
Jie Yuan Ning Song Nabil Farhat Jan Van der Spiegel 《Analog Integrated Circuits and Signal Processing》2009,59(3):287-300
The clustering of spatio-temporal patterns are essential for many applications. Established from the biological analogy of
the cortex, the parametrically coupled logistic map network (PCLMN) provides a viable solution to the clustering problem.
To engineer for a single-chip spatio-temporal pattern clustering system, the highly modular PCLMN is designed in analog circuit.
In this paper, the 0.6 μm 5 V CMOS design of the processing element is presented. The analog design employs self-calibration
techniques to improve the accuracy and robustness of the nonlinear circuits. A fabricated element covers a die area of 0.55
mm2, and consumes 240 mW power at 5 V supply. After calibration, simulation and testing results show that the element fulfills
the system-level requirement of the Cort-X model for driving signals up to 1 MHz. 相似文献
93.
94.
Swift Joshua K.; Callahan Jennifer L.; Heath Christopher J.; Herbert Gregory L.; Levine Jason C. 《Canadian Metallurgical Quarterly》2010,47(2):235
While previous research on deterioration has focused on identifying individuals at risk for negative outcomes, little is known about the nature or pattern by which deterioration occurs. The problem of deterioration is especially salient in training clinics; a setting in which higher deterioration rates have been reported. Two studies were designed to test the applicability of the phase model to deterioration in a training clinic and to replicate the model with a training clinic referral-base sample. In Study 1, the course of therapy was monitored for 135 clients. For the 38 clients who deteriorated during therapy, a model where increased symptoms (demediation) reliably preceded both decreased functioning (dehabilitation) and decreased well-being (demoralization) was found. In Study 2, the same three phases were prospectively monitored for 914 undergraduate students on a weekly basis throughout a single semester. For the 158 individuals who deteriorated during this time, a model where demediation reliably preceded dehabilitation, which preceded demoralization was found. These results have clinical implications for the use of tailored intervention strategies focusing on the deterioration phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
96.
97.
98.
William Rowe Mark Platt David C. Wedge Philip J. Day Douglas B. Kell Joshua Knowles 《Journal of the Royal Society Interface》2010,7(44):397-408
Properties of biological fitness landscapes are of interest to a wide sector of the life sciences, from ecology to genetics to synthetic biology. For biomolecular fitness landscapes, the information we currently possess comes primarily from two sources: sparse samples obtained from directed evolution experiments; and more fine-grained but less authentic information from ‘in silico’ models (such as NK-landscapes). Here we present the entire protein-binding profile of all variants of a nucleic acid oligomer 10 bases in length, which we have obtained experimentally by a series of highly parallel on-chip assays. The resulting complete landscape of sequence-binding pairs, comprising more than one million binding measurements in duplicate, has been analysed statistically using a number of metrics commonly applied to synthetic landscapes. These metrics show that the landscape is rugged, with many local optima, and that this arises from a combination of experimental variation and the natural structural properties of the oligonucleotides. 相似文献
99.
Amr Ahmed Andrew Arnold Luis Pedro Coelho Joshua Kangas Abdul-Saboor Sheikh Eric Xing William Cohen Robert F. Murphy 《Journal of Web Semantics》2010,8(2-3):151-154
The SLIF project combines text-mining and image processing to extract structured information from biomedical literature.SLIF extracts images and their captions from published papers. The captions are automatically parsed for relevant biological entities (protein and cell type names), while the images are classified according to their type (e.g., micrograph or gel). Fluorescence microscopy images are further processed and classified according to the depicted subcellular localization.The results of this process can be queried online using either a user-friendly web-interface or an XML-based web-service. As an alternative to the targeted query paradigm, SLIF also supports browsing the collection based on latent topic models which are derived from both the annotated text and the image data.The SLIF web application, as well as labeled datasets used for training system components, is publicly available at http://slif.cbi.cmu.edu. 相似文献
100.
Malkanthi Evans Joshua Baisley Sonya Barss Najla Guthrie 《Journal of Functional Foods》2009,1(1):65-73
The bioavailability of a single, 100 mg, dose of reduced Coenzyme Q10 (CoQH-CF) and Coenzyme Q10 formulation was compared in individuals of >60 years. Significantly higher (P < 0.001) plasma concentrations were demonstrated for the CoQH-CF formulation at 5, 6, 8, 12, 24, 48 and 72 h post-dose compared to the CoQ10 formulation. The area under the curve (AUC) of reduced and total Coenzyme Q10 was significantly higher (P < 0.001) in subjects administered CoQH-CF resulting in 4.3-fold higher plasma AUC0–72 h (430% increase) in subjects receiving CoQH-CF compared to subjects receiving Coenzyme Q10. Oxidized Coenzyme Q10 in plasma was higher (P < 0.001) in subjects receiving CoQH-CF compared to subjects receiving Coenzyme Q10 resulting in a 3.3-fold higher plasma AUC0–72 h (329% increase). Total CoQ10 reached maximum plasma concentrations 15.5 ± 19.6 h after supplementation with CoQH-CF and 26.5 ± 25.8 h after supplementation with Coenzyme Q10, respectively. Thus, reduced Coenzyme Q10 liquid soft gel formulation was found to be superior to the commercial formulation of Coenzyme Q10 for bioavailability. 相似文献