全文获取类型
收费全文 | 685篇 |
免费 | 43篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 3篇 |
综合类 | 2篇 |
化学工业 | 160篇 |
金属工艺 | 7篇 |
机械仪表 | 7篇 |
建筑科学 | 53篇 |
矿业工程 | 2篇 |
能源动力 | 34篇 |
轻工业 | 107篇 |
水利工程 | 2篇 |
石油天然气 | 2篇 |
无线电 | 56篇 |
一般工业技术 | 112篇 |
冶金工业 | 81篇 |
原子能技术 | 2篇 |
自动化技术 | 100篇 |
出版年
2023年 | 9篇 |
2022年 | 27篇 |
2021年 | 23篇 |
2020年 | 16篇 |
2019年 | 10篇 |
2018年 | 23篇 |
2017年 | 23篇 |
2016年 | 20篇 |
2015年 | 18篇 |
2014年 | 24篇 |
2013年 | 59篇 |
2012年 | 37篇 |
2011年 | 49篇 |
2010年 | 44篇 |
2009年 | 36篇 |
2008年 | 39篇 |
2007年 | 47篇 |
2006年 | 38篇 |
2005年 | 19篇 |
2004年 | 32篇 |
2003年 | 16篇 |
2002年 | 22篇 |
2001年 | 13篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 8篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1969年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有730条查询结果,搜索用时 15 毫秒
51.
A rejoinder to "Psychotherapy research ethics: Continuing the debate on controlled clinical trials."
Imber Stanley D.; Glanz Lawrence M.; Elkin Irene; Sotsky Stuart M.; Boyer Jenny L.; Leber William R. 《Canadian Metallurgical Quarterly》1987,42(12):1132
Responds to C. A. Heflinger's (1987) critique of the present authors (1986) by reiterating their concern for the principle of autonomy. The present authors note that all patients were fully informed about the research plan and their right to withdraw. Nonetheless, the ethical criticism offered by Heflinger regarding randomization cannot be entirely dismissed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Philip Dobie Julie Dendy Christine Sherman Jenny Padgham Anna Wood Angharad M. R. Gatehouse 《Journal of Stored Products Research》1990,26(4):177-186
The importance of carefully applied bioassay techniques is highlighted for identifying resistance of Phaseolus spp to the bruchids Acanthoscelides obtectus (Say) and Zabrotes subfasciatus Boheman. Two potential sources of resistance are identified amongst the varieties of P. vulgaris screened. In one the presence of a lectin-like protein (LLP) was identified, which has previously been associated with resistance, while in the other, resistance may be linked to the presence of a novel protein, similar to but not the same as LLP. The use of anti-LLP antibodies are suggested as a useful tool for distinguishing between resistant and susceptible varieties. Five varieties of P. lunatus and six of P. acutifolius are shown to be resistant to A. obtectus, and the potential is recognized for transferring resistant genes to P. vulgaris via interspecific crosses. 相似文献
53.
Masaki Horie I.-Wen Shen Henry Leventis Jenny Nelson Michael L. Turner 《Polymer》2010,51(7):1541-11830
Poly(3,4-dioctylthienylenevinylene) (PDOTV) was synthesised by ring-opening metathesis polymerization (ROMP) with controlled molecular weight. PDOTV has been used to fabricate organic photovoltaic devices in combination with phenyl C61-butyric acid methyl ester (PCBM) for the first time. The devices show power conversion efficiency up to 0.18%. Optimal device performance was found at a film thickness of 100 nm and a ratio of PCBM to PTV of 2:1. External quantum efficiency (EQE) measurements, transient absorption spectroscopy and morphology studies were carried out to establish factors governing photovoltaic performance. These results suggest that the efficiency values for the devices were limited by the hole mobility and unexpected phase separation within the blend. Nevertheless, the results show that ROMP is a viable, alternative, synthetic strategy for preparing PTV donors for use in bulk heterojunction OPVs. 相似文献
54.
Jenny Folkesson Eigil Samset Raymond Y Kwong Carl-Fredrik Westin 《IEEE transactions on information technology in biomedicine》2008,12(3):328-334
This paper presents a segmentation method that extends geodesic active region methods by the incorporation of a statistical classifier trained using feature selection. The classifier provides class probability maps based on class representative local features, and the geodesic active region formulation enables the partitioning of the image according to the region information. We demonstrate automatic segmentation results of the myocardium in cardiac late gadolinium-enhanced magnetic resonance imaging (CE-MRI) data using coupled level set curve evolutions, in which the classifier is incorporated both from a region term and from a shape term from particle filtering. The results show potential for clinical studies of scar tissue in late CE-MRI data. 相似文献
55.
This article presents a model of loneliness that incorporates characteristics of the social network, background variables, personality characteristics, and evaluative aspects. The most salient aspect of this approach is its emphasis on cognitive processes that mediate between characteristics of the social network and the experience of loneliness. A total of 554 adult men and women served as respondents. The program LISREL, a causal modelling approach, was used to analyze the data. The LISREL program includes a goodness-of-fit test that indicates the degree of fit between a particular model and the data. The hypothesized model made a valuable contribution to the understanding of loneliness: It accounted for 52.3% of the variance in the data set. One of the model's major advantages is its ability to disentangle both the direct and the indirect causal influences of the various factors on loneliness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
This paper combines engineering and social science approaches to enhance our understanding of industrial energy efficiency and broaden our perspective on policy making in Europe. Sustainable development demands new strategies, solutions, and policy-making approaches. Numerous studies of energy efficiency potential state that cost-effective energy efficiency technologies in industry are not always implemented for various reasons, such as lack of information, procedural impediments, and routines not favoring energy efficiency. Another reason for the efficiency gap is the existence of particular values, unsupportive of energy efficiency, in the dominant networks of a branch of trade. Analysis indicates that different sectors of rather closed communities have established their own tacit knowledge, perceived truths, and routines concerning energy efficiency measures. Actors in different industrial sectors highlight different barriers to energy efficiency and why cost-effective energy efficiency measures are not being implemented. The identified barriers can be problematized in relation to the social context to understand their existence and how to resolve them. 相似文献
57.
Editor's NoteIn the age of mobile media, artists interested in storytelling and place have been exploring various technologies to enable their locative media work. Jenny Weight traces the aesthetic and technical background to these works and discusses recent RMIT projects, which work with a solar powered Bluetooth server to deliver their poetic psychogeographic stories.—Norie Neumark 相似文献
58.
Philip Sandwell Geoffrey Duggan Jenny Nelson Ned Ekins‐Daukes 《Progress in Photovoltaics: Research and Applications》2016,24(11):1458-1472
We present a life cycle analysis of a lightweight design of high concentration photovoltaic module. The materials and processes used in construction are considered to assess the total environmental impact of the module construction in terms of the cumulative energy demand and embodied greenhouse gas emissions, which were found to be 355.3 MJ and 27.9 kgCO2eq respectively. We consider six potential deployment locations and the system energy payback times are calculated to be 0.22–0.33 years whilst the greenhouse gas payback times are 0.29–0.88 years. The emission intensities over the lifetimes of the systems are found to be 6.5–9.8 g CO2eq/kWh, lower than those of other HCPV, PV and CSP technologies in similar locations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
59.
Jenny Faucheu Author Vitae Catherine Gauthier Author Vitae Author Vitae Jean-Yves Cavaillé Author Vitae Author Vitae Elodie Bourgeat Lami Author Vitae 《Polymer》2010,51(1):6-5269
This review intends to present different aspects concerning clay/polymer nanocomposites produced by heterophase polymerization in aqueous media. This paper highlights the ability of miniemulsion polymerization to produce clay/polymer nanoparticles with tailored nanostructures. Indeed, this polymerization route enables the synthesis of composite nanoparticles with the clay platelets located either on the surface of the polymer particle or embedded inside the polymer particle. A focus is given on the influence of these nanostructures on the properties of the final material through a direct comparison of the composites obtained after water evaporation from these structured nanoparticles. Indeed, the film obtained from the film forming process of these nanoparticles present significantly different nanostructures and exhibit totally different mechanical behaviours and water uptakes. By comparing experimental results and modeling approaches, it is demonstrated that their properties are clearly related to the clay dispersion and contacts. It is also evidenced that the main drawback of miniemulsion from the coating application point of view, is the large water uptake promoted by the surfactant presence whose localization is strongly influenced by nanostructuration. This stresses the need for the further development of surfactant free miniemulsion polymerization using advantageously the clay presence to stabilize the emulsion. 相似文献
60.
Pauline Kang Kathleen Watt Tina Chau Jenny Zhu Bruce J.W. Evans Helen Swarbrick 《Contact lens & anterior eye》2018,41(6):501-506