全文获取类型
收费全文 | 1356篇 |
免费 | 71篇 |
国内免费 | 7篇 |
专业分类
电工技术 | 19篇 |
化学工业 | 380篇 |
金属工艺 | 30篇 |
机械仪表 | 22篇 |
建筑科学 | 55篇 |
矿业工程 | 3篇 |
能源动力 | 39篇 |
轻工业 | 124篇 |
水利工程 | 9篇 |
无线电 | 112篇 |
一般工业技术 | 280篇 |
冶金工业 | 93篇 |
原子能技术 | 10篇 |
自动化技术 | 258篇 |
出版年
2024年 | 3篇 |
2023年 | 12篇 |
2022年 | 15篇 |
2021年 | 24篇 |
2020年 | 26篇 |
2019年 | 23篇 |
2018年 | 33篇 |
2017年 | 37篇 |
2016年 | 46篇 |
2015年 | 33篇 |
2014年 | 61篇 |
2013年 | 91篇 |
2012年 | 88篇 |
2011年 | 80篇 |
2010年 | 81篇 |
2009年 | 75篇 |
2008年 | 89篇 |
2007年 | 62篇 |
2006年 | 48篇 |
2005年 | 57篇 |
2004年 | 54篇 |
2003年 | 46篇 |
2002年 | 43篇 |
2001年 | 15篇 |
2000年 | 22篇 |
1999年 | 17篇 |
1998年 | 31篇 |
1997年 | 18篇 |
1996年 | 18篇 |
1995年 | 12篇 |
1994年 | 18篇 |
1993年 | 19篇 |
1992年 | 8篇 |
1991年 | 13篇 |
1990年 | 11篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 10篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 12篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1971年 | 2篇 |
1968年 | 2篇 |
排序方式: 共有1434条查询结果,搜索用时 15 毫秒
41.
WANG Jiang FAUTRELLE Yves REN Zhong-ming LI Xi NGUYEN-THI Henri MANGELINCK-NOEL Nathalie SALLOUM ABOU JAOUDE Georges ZHONG Yun-bo KALDRE Imants BOJAREVICS Andris BULIGINS Leonid 《钢铁研究学报(英文版)》2012,(Z1):381-385
Sn-3wt%Pb alloy was directionally solidified without and with a 0.08T transverse magnetic field(TMF),and real-time recorded by in-situ synchrotron X-ray imaging.Results indicate that TMF shortened the distance from the location of nucleation to the advancing interface,and accelerated the growth rate of the equiaxed crystal,which caused the columnar-to-equiaxed transition(CET)finally.The thermoelectromagnetic convection(TEMC)in front of the interface and around the crystal’s dendritic branch should respond to changes of the distance and the growth rate. 相似文献
42.
Damien Trentesaux Cyrille Pach Abdelghani Bekrar Yves Sallez Thierry Berger Thérèse Bonte Paulo Leitão José Barbosa 《Control Engineering Practice》2013,21(9):1204-1225
Benchmarking is comparing the output of different systems for a given set of input data in order to improve the system’s performance. Faced with the lack of realistic and operational benchmarks that can be used for testing optimization methods and control systems in flexible systems, this paper proposes a benchmark system based on a real production cell. A three-step method is presented: data preparation, experimentation, and reporting. This benchmark allows the evaluation of static optimization performances using traditional operation research tools and the evaluation of control system's robustness faced with unexpected events. 相似文献
43.
44.
Gilles Perrouin Sebastian Oster Sagar Sen Jacques Klein Benoit Baudry Yves le Traon 《Software Quality Journal》2012,20(3-4):605-643
Software Product Lines (SPL) are difficult to validate due to combinatorics induced by variability, which in turn leads to combinatorial explosion of the number of derivable products. Exhaustive testing in such a large products space is hardly feasible. Hence, one possible option is to test SPLs by generating test configurations that cover all possible t feature interactions (t-wise). It dramatically reduces the number of test products while ensuring reasonable SPL coverage. In this paper, we report our experience on applying t-wise techniques for SPL with two independent toolsets developed by the authors. One focuses on generality and splits the generation problem according to strategies. The other emphasizes providing efficient generation. To evaluate the respective merits of the approaches, measures such as the number of generated test configurations and the similarity between them are provided. By applying these measures, we were able to derive useful insights for pairwise and t-wise testing of product lines. 相似文献
45.
Majdala Mansour-Geoffrion Peter L. Dold Daniel Lamarre Alain Gadbois Stéphane Déléris Yves Comeau 《Minerals Engineering》2010,23(4):359-364
Typically, 15–45% of the mixed liquor (sludge) in biological wastewater treatment plants (WWTPs) consists of inorganic (fixed) suspended solids. A portion of these inorganic compounds is grit (sand) originating from the influent. Grit accumulation impacts WWTP design and operating costs as these unbiodegradable solids reduce the effective treatment capacity of the bioreactor and other unit operations that must be sized to carry this material.The goal of this study was to characterize the performance of a hydrocyclone to selectively separate grit from activated sludge. Laboratory experiments were conducted with a 13 mm diameter Krebs hydrocyclone treating sludge from eight WWTPs. Reduced efficiencies of 17 ± 7% on fixed suspended solids and 9 ± 6% on volatile suspended solids were obtained. Grade efficiency curves enabled the development of a modified definition for cut size useful for this application. The characterization of hydrocyclone performance for grit removal from activated sludge will enable modelling of the process for integration into wastewater treatment simulators used for process performance prediction and design. 相似文献
46.
Bulky End‐Capped [1]Benzothieno[3,2‐b]benzothiophenes: Reaching High‐Mobility Organic Semiconductors by Fine Tuning of the Crystalline Solid‐State Order 下载免费PDF全文
Guillaume Schweicher Vincent Lemaur Claude Niebel Christian Ruzié Ying Diao Osamu Goto Wen‐Ya Lee Yeongin Kim Jean‐Baptiste Arlin Jolanta Karpinska Alan R. Kennedy Sean R. Parkin Yoann Olivier Stefan C. B. Mannsfeld Jérôme Cornil Yves H. Geerts Zhenan Bao 《Advanced materials (Deerfield Beach, Fla.)》2015,27(19):3066-3072
47.
A Novel Technology for Natural Gas Conversion by Means of Integrated Oxidative Coupling and Dry Reforming of Methane 下载免费PDF全文
Dr. Joris W. Thybaut Prof. Guy B. Marin Dr. Claude Mirodatos Dr. Yves Schuurman Dr. Andre C. van Veen Prof. Vladislav A. Sadykov Dr. Helmut Pennemann Dr. Rainer Bellinghausen Prof. Leslaw Mleczko 《化学,工程师,技术》2014,86(11):1855-1870
A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO2, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming. 相似文献
48.
Pierre Yves Le Gac Morgane Broudin Gérard Roux Jacques Verdu Peter Davies Bruno Fayolle 《Polymer》2014
Tensile properties and crack propagation properties, especially critical strain energy release rate in mode I, GIC, have been used to investigate fracture properties of elastomers and their relationships with microstructure. These investigations were mainly based on a series of comparisons: first, the behaviour of polychloroprene rubber (CR), undergoing stress hardening due to strain induced crystallization (SIC) and oxidative crosslinking (OCL) was compared with that of chlorinated polyethylene (CPE), which undergoes SIC but not OCL, and with a polyurethane based on hydroxyl terminated polybutadiene (PU) which undergoes OCL but not SIC. Comparisons were also made on CR between fracture behaviour at ambient temperature, where SIC occurs and at 100 °C where there is no SIC. Finally, oxidative crosslinking was used to vary in a continuous way the crosslink density in CR and PU, in order to evaluate the role of crosslinking in fracture behaviour. 相似文献
49.
50.
Characterization of activated sludge flocs by confocal laser scanning microscopy and image analysis 总被引:7,自引:0,他引:7
Schmid M Thill A Purkhold U Walcher M Bottero JY Ginestet P Nielsen PH Wuertz S Wagner M 《Water research》2003,37(9):2043-2052
In this study we present a new approach to determine volumes, heterogeneity factors, and compositions of the bacterial population of activated sludge flocs by 3D confocal imaging. After staining the fresh flocs with fluorescein-isothiocyanate, 75 stacks of images (containing approx. 3000 flocs) were acquired with a confocal laser scanning microscope. The self-developed macro 3D volume and surface determination for the KS 400 software package combined the images of one stack to a 3D image and calculated the real floc volume and surface. We determined heterogeneity factors like the ratio of real floc surface to the surface of a sphere with the respective volume and the fractal dimension (D(f)). According to their significant influence on floc integrity and quality, we also investigated the chemical composition of flocs and quantified their bacterial population structure by using group-specific rRNA-targeted probes for fluorescence in situ hybridization. By a settling experiment we enriched flocs with poor settling properties and determined the above-mentioned parameters. This approach revealed shifts in floc volume, heterogeneity, and bacterial and chemical composition according to the settling quality of the flocs. 相似文献