全文获取类型
收费全文 | 402篇 |
免费 | 15篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 92篇 |
金属工艺 | 12篇 |
机械仪表 | 2篇 |
建筑科学 | 11篇 |
矿业工程 | 1篇 |
能源动力 | 6篇 |
轻工业 | 65篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 8篇 |
一般工业技术 | 77篇 |
冶金工业 | 40篇 |
原子能技术 | 3篇 |
自动化技术 | 94篇 |
出版年
2023年 | 4篇 |
2022年 | 25篇 |
2021年 | 30篇 |
2020年 | 11篇 |
2019年 | 4篇 |
2018年 | 17篇 |
2017年 | 7篇 |
2016年 | 12篇 |
2015年 | 15篇 |
2014年 | 13篇 |
2013年 | 20篇 |
2012年 | 29篇 |
2011年 | 24篇 |
2010年 | 10篇 |
2009年 | 18篇 |
2008年 | 22篇 |
2007年 | 18篇 |
2006年 | 15篇 |
2005年 | 10篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 8篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 12篇 |
1997年 | 5篇 |
1996年 | 9篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有417条查询结果,搜索用时 15 毫秒
1.
Angela Altomare Carmelo Giacovazzo Anna Grazia Giuseppina Moliterni Rosanna Rizzi 《Journal of research of the National Institute of Standards and Technology》2004,109(1):125-132
The ab-initio crystal structure solution by powder diffraction data requires great efforts because of the collapse of the experimental information onto the one dimensional 2θ axis of the pattern. Different strategies will be described aiming at improving the process of extraction of the integrated intensities from the experimental pattern in order to make more straightforward the structure solution process by direct methods. Particular attention will be devoted to the EXPO program. Some of its performance will be analysed and results will be shown. 相似文献
2.
3.
4.
In the context of comparative analysis of protein–protein interaction graphs, we use a graph-based formalism to detect the preservation of a given protein complex (pattern graph) in the protein–protein interaction graph (target graph) of another species with respect to (w.r.t.) orthologous proteins. We give an efficient exponential-time randomized algorithm in case the occurrence of the pattern graph in the target graph is required to be exact. For approximate occurrences, we prove a tight inapproximability result and give four approximation algorithms that deal with bounded degree graphs, small ortholog numbers, linear forests and very simple yet hard instances, respectively. 相似文献
5.
Rosanna E. Guadagno Nicole L. MuscanellBradley M. Okdie Nanci M. BurkThomas B. Ward 《Computers in human behavior》2011,27(1):304-308
The present study examined whether traditional gender role expectations (Eagly, 1987) influence behaviors in non-traditional contexts such as online virtual environments. Participants were 352 Second Life users who reported their activities and experiences in Second Life. Results indicated that men and women differed in the types of activities they engaged in a manner predicted by social role theory. Specifically, as compared to women, men were more likely to report building things (e.g. objects), to own and work on their own virtual property, and were less likely to change their avatar’s appearance. Women, as compared to men, were more likely to meet people, shop, regularly change their avatar’s appearance, and buy clothes/objects for their avatar. The present study adds to our understanding of how traditional gender role expectations may carry over to online virtual worlds and influence online behavior. 相似文献
6.
Rosanna E. Guadagno Kimberly R. Swinth Jim Blascovich 《Computers in human behavior》2011,27(6):2380-2385
The purpose of this study was to examine social evaluations (i.e., perceptions of empathy and positivity) following peoples’ interactions with digital human representations. Female research participants engaged in a 3-min interaction while immersed in a 3-D immersive virtual environment with a “peer counselor.” Participants were led to believe that the peer counselor was either an embodied agent (i.e., computer algorithm) or an avatar (i.e., another person). During the interaction, the peer counselor either smiled or not. As predicted, a digitally-rendered smile was found to affect participants’ social evaluations. However, these effects were moderated by participants’ beliefs about their interaction partner. Specifically, smiles enhanced social evaluations of embodied agents but degraded them for avatars. Although these results are consistent with other findings concerning the communicative realism of embodied agents and avatars they uniquely demonstrate that people’s beliefs alone, rather than actual differences in virtual representations, can impact social evaluations. 相似文献
7.
A spectroradiometer was developed for use on the ground and aboard ship. The instrument separates global and diffuse solar radiation with a rotating shading band. Calibration results are compared with those of other sun photometers. The instrument was also mounted on a stabilized platform during an experimental trial aboard ship on the Tyrrhenian Sea. Results are comparable with those obtained by handheld sun photometer. 相似文献
8.
Inter-business collaborative contexts prefigure a distributed scenario where companies organize and coordinate themselves to develop common and shared opportunities, but traditional business intelligence systems do not provide support to this end. To fill this gap, in this paper we envision a peer-to-peer data warehousing architecture based on a network of heterogeneous peers, each exposing query answering functionalities aimed at sharing business information. To enhance the decision making process, an OLAP query expressed on a peer needs to be properly reformulated on the local multidimensional schemata of the other peers. To this end, we present a language for the definition of mappings between the multidimensional schemata of peers and we introduce a query reformulation framework that relies on the translation of mappings, queries, and multidimensional schemata onto the relational level. Then, we formalize a query reformulation algorithm and prove two properties: correctness and closure, that are essential in a peer-to-peer setting. Finally, we discuss the main implementation issues related to the reformulation setting proposed, with specific reference to the case in which the local multidimensional engines hosted by peers use the standard MDX language. 相似文献
9.
10.
José L. Rodríguez Rosanna M. Minardi Erica P. Schulz Olga Pieroni Pablo C. Schulz 《Journal of surfactants and detergents》2012,15(2):147-155
The composition of the mixed micelles formed by benzethonium chloride and dodecyl trimethyl ammonium bromide in water were
experimentally determined by a combination of surfactant ion-selective electrodes and UV–Vis spectroscopy measurements. Results
were compared with the computed compositions from three theories on mixed micelles available in the literature (Regular Solution,
Motomura’ and Georgiev’s). The basis of the Junquera and Aicart method and the determination of the micelle aggregation number
(N) by pyrene fluorescence quenching, i.e., the constancy of N and the mixed micelle composition when the total concentration is changed, were not supported by our experimental results. Experimental micelle compositions were statistically equal to those computed
by Regular Solution Theory. The mixed micelle composition and the quantity of non-micellized surfactant molecules change with
concentration above the critical micelle concentration, and therefore do not support the assumptions used in the Junquera
and Aicart procedure and in the determination of N by pyrene fluorescence quenching. The reason why the latter procedure gives N values similar to those obtained from other techniques is discussed. 相似文献