全文获取类型
收费全文 | 334篇 |
免费 | 24篇 |
专业分类
电工技术 | 5篇 |
综合类 | 1篇 |
化学工业 | 82篇 |
金属工艺 | 12篇 |
机械仪表 | 12篇 |
建筑科学 | 20篇 |
矿业工程 | 5篇 |
能源动力 | 15篇 |
轻工业 | 22篇 |
水利工程 | 2篇 |
无线电 | 28篇 |
一般工业技术 | 67篇 |
冶金工业 | 12篇 |
自动化技术 | 75篇 |
出版年
2023年 | 8篇 |
2021年 | 20篇 |
2020年 | 13篇 |
2019年 | 19篇 |
2018年 | 15篇 |
2017年 | 11篇 |
2016年 | 18篇 |
2015年 | 19篇 |
2014年 | 20篇 |
2013年 | 21篇 |
2012年 | 15篇 |
2011年 | 33篇 |
2010年 | 20篇 |
2009年 | 23篇 |
2008年 | 21篇 |
2007年 | 9篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1985年 | 5篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1963年 | 2篇 |
排序方式: 共有358条查询结果,搜索用时 203 毫秒
1.
Marcus Weyd Christian Pflieger Andy Vogel Hannes Richter Volker Prehn Christiane Günther Frank Splittgerber Alessa Gäbler Daniel Kaulbars Patrick Bräutigam Marcus Franke Samira Lambertz Julian Schlechtweg Ingolf Voigt 《化学,工程师,技术》2021,93(9):1432-1439
Reducing micropollutant pollution of water bodies is an important objective of water management and an integral part of environmental policy. Ceramic nanofiltration membranes were developed as multichannel membranes of increased membrane area and rotating disk filters. The membranes developed show retention of over 80 % for PEG 400. The membranes are currently being tested for the separation of micropollutants from wastewater contaminated with pharmaceuticals. With the help of a downstream oxidative process, the trace substances remaining in the permeate are degraded. 相似文献
2.
Dr. Hannes M. Beyer Dr. Hideo Iwaï 《Chembiochem : a European journal of chemical biology》2019,20(15):1933-1938
Protein-splicing domains are frequently used engineering tools that find application in the in vivo and in vitro ligation of protein domains. Directed evolution is among the most promising technologies used to advance this technology. However, the available screening systems for protein-splicing activity are associated with bottlenecks such as the selection of pseudo-positive clones arising from off-pathway reaction products or fragment complementation. Herein, we report a stringent screening method for protein-splicing activity in cis and trans, that exclusively selects productively splicing domains. By fusing splicing domains to an intrinsically disordered region of the antidote from the Escherichia coli CcdA/CcdB type II toxin/antitoxin system, we linked protein splicing to cell survival. The screen allows selecting novel cis- and trans-splicing inteins catalyzing productive highly efficient protein splicing, for example, from directed-evolution approaches or the natural intein sequence space. 相似文献
3.
Mylena M.M. Carrijo Hannes Lorenz Carlos R. Rambo Peter Greil Nahum Travitzky 《Ceramics International》2018,44(7):8116-8124
This paper describes the development and fabrication of pastes suitable for screen printing process using Ti3SiC2 as the ceramic filler and ethyl cellulose as the binder. With the aim of obtaining high quality screen printed films, the influence of different amounts of Ti3SiC2 filler (20–40?vol%) and binder (0–5?vol%) on the rheological properties of the pastes was investigated. Samples with higher viscosity, such as pastes containing 30?vol% and 40?vol% Ti3SiC2 filler, regardless of the amount of ethyl cellulose, showed a higher printing quality compared to the samples with other compositions. The different paste compositions were screen printed onto paper-derived Al2O3 substrates containing 28.6 ± 4.8% open porosity and sintered for 1?h under an argon atmosphere at 1600?°C. X-ray diffraction (XRD) measurements and scanning electron microscopy (SEM) analysis showed that the sintered films contained TiC as a primary phase and Ti3SiC2 as a secondary phase. The partial decomposition of Ti3SiC2 after sintering can be attributed to residual carbon from the organic additives, which decreases the thermal stability of this material. 相似文献
4.
Volker Kahlenberg Johan P.R. de Villiers Dirk Odendaal Hannes Krüger Shengqiang Song Mithun Nath 《Journal of the American Ceramic Society》2019,102(11):6968-6979
Polycrystalline material of a novel phase in the system CaO–Al2O3–Cr2O3 has been obtained by solid-state reactions. Chemical analysis indicated the composition CaAl2Cr2O7. Single-crystal growth of the new compound using borax as a mineralizer was successful. Diffraction experiments at ambient conditions on a crystal with composition CaAl2.13Cr1.87O7 yielded the following basic crystallographic data: space group P 3, a = 7.7690(5) Å, c = 7.6463(5) Å, V = 399.68(6) Å3, Z = 3. Structure determination and subsequent least-squares refinements resulted in a residual of R(|F|) = 2.3% for 1440 independent observed reflections and 113 parameters. To the best of our knowledge, the structure of CaAl2.13Cr1.87O7 or CaAl2Cr2O7 represents a new structure type. It belongs to the group of double layer structures where individual double layers contain octahedrally and tetrahedrally coordinated cation positions. Linkage between neighboring sheet packages is provided by additional calcium cations. Furthermore, thermal expansion has been studied in the interval between 29 and 790°C using in situ high-temperature single-crystal diffraction. No indications for a structural phase transition were observed. From the evolution of the lattice parameters the thermal expansion tensor has been obtained. A pronounced anisotropy is evident. The response of structural building units to variable temperature has been discussed. 相似文献
5.
Low‐Temperature Chemical Synthesis of High‐Purity Diacylglycerols (DAG) from Monoacylglycerols (MAG) 下载免费PDF全文
A chemical method was developed for low‐temperature synthesis of DAG from MAG followed by an easy purification procedure in order to obtain high‐purity DAG. Solvent‐assisted and solvent‐free reaction conditions were used, combined with different catalysts (sodium methoxide, p‐toluenesulfonic acid, methanesulfonic acid, and sulfuric acid). All reactions were performed at 35 and 70 °C. By increasing both acidity and polarity of the catalyst the equilibrium shifts towards the formation of DAG. When using sulfuric acid in solvent‐assisted condition at 70 °C, 88 % conversion was obtained after 20 min of reaction (77 % w/w DAG in the reaction mixture after evaporation of the solvent). After purifying by means of column chromatography, 96 % pure DAG were obtained. The overall yield of DAG was 81 %. 相似文献
6.
7.
Jasmin Hofstetter Carlos del Caizo Hannes Wagner Sergio Castellanos Tonio Buonassisi 《Progress in Photovoltaics: Research and Applications》2016,24(1):122-132
Silicon wafers comprise approximately 40% of crystalline silicon module cost and represent an area of great technological innovation potential. Paradoxically, unconventional wafer‐growth techniques have thus far failed to displace multicrystalline and Czochralski silicon, despite four decades of innovation. One of the shortcomings of most unconventional materials has been a persistent carrier lifetime deficit in comparison to established wafer technologies, which limits the device efficiency potential. In this perspective article, we review a defect‐management framework that has proven successful in enabling millisecond lifetimes in kerfless and cast materials. Control of dislocations and slowly diffusing metal point defects during growth, coupled to effective control of fast‐diffusing species during cell processing, is critical to enable high cell efficiencies. To accelerate the pace of novel wafer development, we discuss approaches to rapidly evaluate the device efficiency potential of unconventional wafers from injection‐dependent lifetime measurements. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
UNStudio Ben van Berkel Hannes Pfau Astrid Piber Jin Xing Hufton+Crow Seth Powers 《中国建筑装饰装修》2018,(4)
正UNStudio由Ben van Berkel和Caroline Bos创立,是一个国际性的建筑设计网络。拥有三个全方位服务的国际事务所,分别位于阿姆斯特丹、香港和上海。专于建筑、室内建筑、产品设计、城市发展和基础设施项目。地址:浙江省杭州市钱江新城富春路业主方:凯德集团建筑面积:392526m~2项目年份:2017醒目的裙楼之上坐落着两座流线型的高楼,从中可以饱览钱塘江和西湖的迷人风光。 相似文献
9.
10.