全文获取类型
收费全文 | 171篇 |
免费 | 6篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 52篇 |
金属工艺 | 2篇 |
机械仪表 | 8篇 |
建筑科学 | 10篇 |
能源动力 | 5篇 |
轻工业 | 32篇 |
水利工程 | 1篇 |
石油天然气 | 3篇 |
无线电 | 8篇 |
一般工业技术 | 20篇 |
冶金工业 | 8篇 |
原子能技术 | 5篇 |
自动化技术 | 22篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 8篇 |
2021年 | 8篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 8篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 10篇 |
2008年 | 2篇 |
2007年 | 13篇 |
2006年 | 8篇 |
2005年 | 7篇 |
2004年 | 3篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 7篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有179条查询结果,搜索用时 15 毫秒
91.
Jasper S. Caerteling Johannes I. M. Halman Michael Song André G. Dorée 《Canadian Metallurgical Quarterly》2009,135(11):1211-1221
In this study, we focus on road construction and analyze technology development projects. Based on the business strategy literature and literature on technology policy, we test the relative importance of a firm’s strategies and government as a buyer and champion. Our empirical findings stress the value of government championing behavior. Our results show that in road construction, championing behavior is more important than public technology procurement for project performance. The results even suggest that government championship is more important than a firm’s strategic orientation. 相似文献
92.
Software (digital rights management) DRM solutions have beenavailable for well over two decades and have always been aboutpreventing, inhibiting, restricting and controlling. 相似文献
93.
Nir Halman 《Algorithmica》2007,49(1):37-50
We show that a Simple Stochastic Game (SSG) can be formulated as an LP-type problem. Using this formulation, and the known
algorithm of Sharir and Welzl [SW] for LP-type problems, we obtain the first strongly
subexponential solution for SSGs (a strongly subexponential algorithm has only been known for binary SSGs [L]). Using known
reductions between various games, we achieve the first strongly subexponential solutions for Discounted and Mean Payoff Games.
We also give alternative simple proofs for the best known upper bounds for Parity Games and binary SSGs. To the best of our
knowledge, the LP-type framework has been used so far only in order to yield linear or close to linear time algorithms for
various problems in computational geometry and location theory. Our approach demonstrates the applicability of the LP-type
framework in other fields, and for achieving subexponential algorithms. 相似文献
94.
95.
A longitudinal study examined perceptions of received and provided social support and disregard among members of 248 infertile and fertile married couples. Correlational and structural equation modeling analyses were conducted. Women's and men's perceptions of the amount of social support they gave to and received from their partner were highly positively related. In contrast, agreement between spouses about the amount of provided support was moderate. Both social support and disregard mediated the relationships between stress and marital quality of life. Overall, highly similar patterns of results were found for members of infertile and fertile couples. These results demonstrate the perceptual element of received support and disregard as well as the importance of considering the provider's perspective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Mesrar Laila Benamar Ahmed Jabrane Raouf 《Bulletin of Engineering Geology and the Environment》2020,79(6):3019-3032
Bulletin of Engineering Geology and the Environment - The Miocene marl (MM) or calcareous clays in the southern Rif groove is one of the geological resources located in the region of Taza... 相似文献
97.
Amal M. Metwally Hany I. Mohamed Hanaa A. ElKhawaga Sahar M. Ibrahim Laila M. Reda 《应用聚合物科学杂志》2024,141(10):e55037
Polymeric complexes, especially metal-containing polymers, possess aggregated medical applications, especially as antibacterial and antifungal agents. This work describes a facile procedure for producing a series of novel copper and nickel complexes of poly(2-hydroxyphenyl methacrylamide) and poly(2-carboxyphenyl methacrylamide). The polymeric ligands were synthesized through a multistep procedure. Firstly, 4-formylphenyl methacrylate was constructed by acylating 4-hydroxybenzaldehyde with methacryloyl chloride. Then, polymerization of the as-prepared monomer to obtain poly(4-formylphenyl methacrylate) using benzoyl peroxide as an initiator. Thirdly, the polymeric ligands PL1 and PL2 were achieved via exchange reactions between poly(4-formylphenyl methacrylate) and o-aminophenol and anthranilic acid, respectively. Consequently, the two ligands were reacted with copper and nickel acetates to afford four target complexes (Cu-PL1, Ni-PL1, Cu-PL2, and Ni-PL2). By FT-IR, 1HNMR, UV-visible, and TGA analyses, the structures of PL1, PL2, and their complexes were investigated. Furthermore, the geometries of PL1, PL2, and their complexes were reported through a molecular modeling to investigate some interesting parameters such as the bond length, bond angle, charge on the atoms, the HOMO and LUMO using the Material Studio program. The calculation results illustrated that octahedral geometries are proposed for the synthesized metal complexes. The reported antimicrobial efficiency showed a strong potency for most synthesized compounds against the selected microbes, especially compounds Cu-PL1 and Cu-PL2 which are more effective than the standard against Candida albicans. 相似文献
98.
Laila Saleh 《Renewable Energy》1994,5(1-4)
This paper presents Energy policy and describes the framework of Energy utilization, in Egypt, with special emphasis on wind Energy plans and programs to illustrate the role wind Energy can play in the sustainable Energy development programs in EgyptA Master plan that targets 600 MW by the year 2005 for grid connection is currently worked out, based on 200–300 kw turbine size capacity.National institutions concerned are taking part in master planning of wind Energy utilization, New and Renewable Energy Authority (NREA) under the Ministry of Electricity and Energy in Egypt has the responsibility for promotion of technologies and applicationsThe paper also illustrate demonstration program and projects performance results and present hands on experience gained through the last 5 yearsMoreover the paper presents the National five year plan objectives that calls for 70 MW wind farms at the area of the Red Sea, based on national investment together with 150 MW wind farms in the same area based on private investment, which is a change in the laws due to convection of economical reforming in Egypt. Fuel saving and environmental impact assessment together with economical analysis is presented for the national five year plan 1992/1997. 相似文献
99.
Stéphane Claude Pat Niranjanan Frank Jiang Dave Duncan Dominic Garcia Mark Halman Haoling Ma Ivan Wevers Keith Yeung 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(6-7):563-582
This paper presents the performance of production Band 3 receivers (84-116 GHz) for the Atacama Large Millimeter Array (ALMA) that operate in Chile at 5000 m altitude. The fabrication, and testing of a total of 73 receivers necessitated stringent quality control during assembly and custom designed automated test set for accurate and reproducible measurement results. Interfaces to the ALMA receiver system are described in details. The average single side band noise temperature of band 3 production receivers is 33.2 K, with a minimum of 24.4 K and a maximum of 45.5 K. As for image rejection, the average is 18 dB, with a minimum at 12 dB and a maximum of 21 dB. Other performances with test methodology are described such as gain variation within the IF band, the gain and phase stability, gain compression, and beam patterns. This paper also describes the interfaces to the ALMA front end system, the testing methodology used, and the test results. 相似文献
100.
Rokka M Eerola S Perttilä U Rossow L Venäläinen E Valkonen E Valaja J Peltonen K 《Molecular nutrition & food research》2005,49(1):38-42
Laying hens were fed contaminated feed containing narasin 2.5 mg/kg for 21 days followed by a 7 day withdrawal period, hens in the control group were fed unmedicated feed. Eggs were collected during trial days 0, 3, 7, 14, 21 and after the withdrawal period of 7 days. The concentration of narasin in yolks and egg whites was analyzed by a liquid chromatography-mass spectrometry method. Narasin was found to accumulate in yolks, where the narasin concentration increased during the treatment. The concentration of narasin varied from 5.9 to 13.8 microg/kg (mean 10.6 microg/kg) in yolks after 21 day feeding periods. The concentrations of narasin ranged from < 0.9 to 1.4 microg/kg after the withdrawal period. Narasin residues were not found in egg whites of the laying hens fed contaminated feed nor in either yolks or egg whites of the laying hens fed unmedicated feed. The effect of cooking was also tested on the amount of narasin residues in eggs. Cooking for 10 min did not significantly influence the narasin residues in eggs. Traces of lasalocid were also found in the yolks. The traces of lasalocid are attributable to an accidental contamination of the feed during its manufacture. 相似文献