全文获取类型
收费全文 | 513篇 |
免费 | 40篇 |
专业分类
电工技术 | 12篇 |
化学工业 | 111篇 |
金属工艺 | 8篇 |
机械仪表 | 7篇 |
建筑科学 | 10篇 |
能源动力 | 9篇 |
轻工业 | 49篇 |
水利工程 | 5篇 |
石油天然气 | 1篇 |
无线电 | 35篇 |
一般工业技术 | 70篇 |
冶金工业 | 105篇 |
自动化技术 | 131篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 2篇 |
2021年 | 22篇 |
2020年 | 8篇 |
2019年 | 16篇 |
2018年 | 14篇 |
2017年 | 17篇 |
2016年 | 25篇 |
2015年 | 9篇 |
2014年 | 26篇 |
2013年 | 36篇 |
2012年 | 35篇 |
2011年 | 27篇 |
2010年 | 17篇 |
2009年 | 46篇 |
2008年 | 21篇 |
2007年 | 13篇 |
2006年 | 19篇 |
2005年 | 12篇 |
2004年 | 14篇 |
2003年 | 17篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 34篇 |
1997年 | 26篇 |
1996年 | 20篇 |
1995年 | 5篇 |
1994年 | 10篇 |
1993年 | 11篇 |
1992年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有553条查询结果,搜索用时 15 毫秒
1.
2.
Pablo Salcedo-Abraira Sergio M.F.Vilela Artem A.Babaryk Maria Cabrero-Antonino Pedro Gregorio Fabrice Salles Sergio Navalon Hermenegildo Garcia Patricia Horcajada 《Nano Research》2021,14(2):450-457
A novel microporous two-dimensional(2D)Ni-based phosphonate metal-organic framework(MOF;denoted as IEF-13)has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational techniques.Structure resolution by single-crystal X-ray diffraction reveals that IEF-13 crystallizes in the triclinic space group Pi having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ligand.Remarkably,this material exhibits coordinatively unsaturated nickel(II)sites,free-P03H2and-P03H acidic groups,a C02accessible microporosity,and an exceptional thermal and chemical stability.Further,its in-deep optoelectronic characterization evidences a photoresponse suitable for photocatalysis.In this sense,the photocatalytic activity for challenging H2generation and overall water splitting in absence of any co-catalyst using UV-Vis irradiation and simulated sunlight has been evaluated,constituting the first report for a phosphonate-MOF photocatalyst.IEF-13 is able to produce up to 2,200 fimol of H2per gram using methanol as sacrificial agent,exhibiting stability,maintaining its crystal structure and allowing its recycling.Even more,170μmol of H2per gram were produced using IEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting,being this reaction limited by the 02reduction.The present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials. 相似文献
3.
Scientometrics - Bibliometrics, and more generally all metric indicators, are increasingly used as research tools as well as for managing and evaluating research activities. This study analyzes the... 相似文献
4.
Maria Pemartín Gregorio Sánchez-Marín José Luis Munuera-Alemán 《Industry and innovation》2019,26(1):57-77
Since new product development (NPD) collaborations with external partners have become the next generation in NPD practices, relationship promoters have become especially relevant as key contributors to the success of this type of inter-organisational collaboration. To realise successful outcomes in NPD collaborations, partners face the challenge of effectively integrating the role of relationship promoter into their existing and essential relationships of trust. It is within this context that this paper examines the role of the relationship promoter, by analysing its moderating effect on the relationship between trust and the outcomes of NPD collaboration – including new product competitiveness and partner satisfaction. We test our hypotheses against survey data from 107 innovative firms involved in NPD collaboration with the help of relationship promoters. The results show that, while a non-significant influence can be reported about the presence of a relationship promoter in terms of partner satisfaction, the relationship promotor weakens the influence of trust on new product competitiveness, making trust less important when it comes to creating a competitive new product. 相似文献
5.
6.
Pablo Toharia Oscar D. Robles Ricardo Suárez Jose Luis Bosque Luis Pastor 《Journal of Parallel and Distributed Computing》2012
This paper presents an analysis of a Multi-GPU Multi-CPU environment, along with the different possible hybrid combinations. The analysis has been performed for a shot boundary detection application, based on Zernike moments, although it is general enough to be applied to many different application areas. A deep study of the performance, bottlenecks and design challenges is carried out showing the validity of this approach and achieving very high frame per second rates. In this paper, Zernike calculations are carried out on GPUs, taking advantage of a packing strategy proposed to minimize host-device communication time. 相似文献
7.
Modern human societies have evolved into an almost entirely connected world, giving place to a remarkable increase in social interactions. In this new context and because of the globalization of all human activities, the collective participation in decision‐making processes takes an increasingly prominent role. In this paper, a method for group decision making from a set of imprecise opinions called “moviQuest Decision Making” (MQDM), is presented. This method allows to integrate the opinions of heterogeneous groups of agents in a structured social network along a sequence of voting rounds for collective decision making. 相似文献
8.
9.
Pleurotus ostreatus spent mushroom substrate for the degradation of polycyclic aromatic hydrocarbons: the case study of a pilot dynamic biopile for the decontamination of a historically contaminated soil 下载免费PDF全文
10.
F??bio da Silva Lisboa Gregorio Guadalupe Carbajal Ar??zaga Fernando Wypych 《Topics in Catalysis》2011,54(8-9):474-481
Layered lanthanum and copper(II) laurates were tested as catalysts for methanolic esterification of lauric acid (C12). Factorial design evidenced a positive effect of reaction temperature and amount of catalyst on ester conversion, while the acid:alcohol molar ratio (MR) had a negative effect. With lanthanum laurate, 90.5% conversion was reached at 140???C with 10% catalyst and MR of 6:1. Although the highest conversion with copper(II) laurate converted 81.5% under the same conditions, results were better with a lower amount of catalyst (78% ester at 140???C with 2% catalyst and MR of 6:1). A calcium hydroxide succinate was also investigated showing better catalytic performance than the well-known CaO, under mild reaction conditions (120???C with 1% catalyst and MR of 3:1). Although layered carboxylates can be successively reused, the layered calcium hydroxide salt transformed into inactive CaCO3 in the second reuse reaction. 相似文献