全文获取类型
收费全文 | 172篇 |
免费 | 12篇 |
专业分类
化学工业 | 62篇 |
建筑科学 | 9篇 |
矿业工程 | 2篇 |
能源动力 | 4篇 |
轻工业 | 41篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 5篇 |
一般工业技术 | 29篇 |
冶金工业 | 9篇 |
自动化技术 | 21篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 21篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 10篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 9篇 |
2014年 | 5篇 |
2013年 | 10篇 |
2012年 | 16篇 |
2011年 | 18篇 |
2010年 | 5篇 |
2009年 | 8篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有184条查询结果,搜索用时 62 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.
Mangrove forests as a nature-based solution for coastal flood protection: Biophysical and ecological considerations 下载免费PDF全文
Rosanna van Hespen Zhan Hu Bas Borsje Michela De Dominicis Daniel A. Friess Svetlana Jevrejeva Maarten G. Kleinhans Maria Maza Celine E. J. van Bijsterveldt Tom Van der Stocken Bregje van Wesenbeeck Danghan Xie Tjeerd J. Bouma 《水科学与水工程》2023,16(1):1-13
Nature-based coastal protection is increasingly recognised as a potentially sustainable and cost-effective solution to reduce coastal flood risk. It uses coastal ecosystems such as mangrove forests to create resilient designs for coastal flood protection. However, to use mangroves effectively as a nature-based measure for flood risk reduction, we must understand the biophysical processes that govern risk reduction capacity through mangrove ecosystem size and structure. In this perspective, we evaluate the current state of knowledge on local physical drivers and ecological processes that determine mangrove functioning as part of a nature-based flood defence. We show that the forest properties that comprise coastal flood protection are well-known, but models cannot yet pinpoint how spatial heterogeneity of the forest structure affects the capacity for wave or surge attenuation. Overall, there is relatively good understanding of the ecological processes that drive forest structure and size, but there is a lack of knowledge on how daily bed-level dynamics link to long-term biogeomorphic forest dynamics, and on the role of combined stressors influencing forest retreat. Integrating simulation models of forest structure under changing physical (e.g. due to sea-level change) and ecological drivers with hydrodynamic attenuation models will allow for better projections of long-term natural coastal protection. 相似文献
3.
M Lise D Nitti A Marchet T Sahmoud N Duez A Fornasiero JG dos Santos R Labianca P Lasser M Gignoux 《Canadian Metallurgical Quarterly》1995,2(6):495-501
BACKGROUND: The high incidence of locoregional recurrences and distant metastases after curative surgery for gastric cancer calls for improved locoregional control and systemic adjuvant treatment. METHODS: In a randomized clinical trial on adjuvant FAM2 chemotherapy, quality of surgery was evaluated by comparing surgical and pathology data. Univariate and multivariate analysis was made to evaluate the effect of prognostic factors on survival and time of recurrence in relation to patients, tumor, and therapy. RESULTS: Of 314 patients randomized from 28 European institutions, 159 comprised the control and 155 the FAM2 group. After a median follow-up of 80 months, no statistically significant difference was found between survivals. However, for recurrence time, treated patients had a significant advantage over controls (p = 0.02). At univariate analysis, statistically significant differences in survival and time to progression emerged for T, N, disease stage and "adequacy" of surgery. The multivariate analysis retained preoperative Hb level, T, N, and "adequacy" of surgery for time of survival; and T, N, "adequacy" of surgery and adjuvant chemotherapy for recurrence time. CONCLUSIONS: Disease stage is the most important prognostic factor. "Adequate" surgery has an important effect. Adjuvant FAM2 delayed time of recurrence, but did not influence overall survival. 相似文献
4.
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.
This paper describes an approach used to evaluate the performance of different supply chain configurations in customised contexts. Based on historical data collected from the supply chain of a shoe producer, different configurations are evaluated based on a discrete-event simulation by highlighting the performance of the supply chain (in terms of supply chain order lead-time and inventory volume) when the production switched from standard production (characterised by batches of large quantities of the same product) to customised production (characterised by a small of series batches with high product variability). The simulation approach relies on experimentation through executable configurations, which enables the creation of different scenarios, and is then applied to the case of an actual firm in the footwear industry. The managerial implications of these findings are discussed. 相似文献
8.
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
9.
10.
This study aimed to investigate the rheology of two-mineral mixture systems as a function of pH and solid concentration. Single minerals (nickel oxide, quartz and hematite) and two-mineral systems (nickel oxide–quartz and nickel oxide–hematite) were studied. Rheology tests were conducted to investigate the effect of pH and solid concentration on shear yield stress of suspensions while zeta potential measurements of suspensions were used to explain the rheology results. Rheology results indicated that single mineral experiments showed that 5 and 10 vol.% of quartz and hematite had no shear yield stress whereas the one of nickel oxide was positive value. Shear yield stress of nickel oxide–quartz mixture and nickel oxide–hematite mixtures increased as increasing pH and solid concentration, and the value was higher than the one obtained with only nickel oxide. These results obtained with two-mineral mixture systems were explained by electrokinetic properties of the minerals, i.e. zeta potential of the minerals. 相似文献