全文获取类型
收费全文 | 1039篇 |
免费 | 83篇 |
国内免费 | 19篇 |
专业分类
电工技术 | 49篇 |
综合类 | 13篇 |
化学工业 | 197篇 |
金属工艺 | 29篇 |
机械仪表 | 49篇 |
建筑科学 | 40篇 |
矿业工程 | 14篇 |
能源动力 | 46篇 |
轻工业 | 245篇 |
水利工程 | 11篇 |
石油天然气 | 10篇 |
武器工业 | 3篇 |
无线电 | 75篇 |
一般工业技术 | 139篇 |
冶金工业 | 40篇 |
原子能技术 | 10篇 |
自动化技术 | 171篇 |
出版年
2024年 | 2篇 |
2023年 | 26篇 |
2022年 | 105篇 |
2021年 | 128篇 |
2020年 | 66篇 |
2019年 | 52篇 |
2018年 | 37篇 |
2017年 | 29篇 |
2016年 | 27篇 |
2015年 | 37篇 |
2014年 | 30篇 |
2013年 | 203篇 |
2012年 | 48篇 |
2011年 | 56篇 |
2010年 | 62篇 |
2009年 | 47篇 |
2008年 | 23篇 |
2007年 | 13篇 |
2006年 | 23篇 |
2005年 | 18篇 |
2004年 | 11篇 |
2003年 | 14篇 |
2002年 | 9篇 |
2001年 | 13篇 |
2000年 | 11篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1932年 | 1篇 |
1927年 | 1篇 |
1919年 | 1篇 |
1909年 | 1篇 |
排序方式: 共有1141条查询结果,搜索用时 15 毫秒
1.
2.
An alternative Equivalent Electrical Circuit for Proton Exchange Membrane Fuel Cells is modelled in this study. Both I–V characteristics and H2 consumptions corresponding to generated power under load and no-load conditions are investigated. For this purpose, H2 consumptions and I–V characteristics of three different sized PEMFCs are tested. There is a very good harmony between the model results and measured values (relative error %0.7, %6.4 and %2.5 for FC-A, FC-B and FC-C respectively). In the proposed model current passes only on parallel resistance and not on serial resistance at no-load condition. Thus, a FC with higher parallel resistance should be preferred. Another key output of this study is that based on the proposed model, performance comparison of FCs can be performed with the parameters defined in this work. Proposals made in this study can easily be used for performance analysis of FCs under for both steady state and transient analysis. 相似文献
3.
4.
Arif Karademir Cem Aydemir Semiha Yenidogan Emine Arman Kandırmaz Rukiye G. Kıter 《Color research and application》2020,45(6):1170-1178
Alkyd resins are generally used in the production of printing inks. All industries look for alternative raw materials in the production of ink with the growing inclination toward using natural products. Resins forming the vehicle of the ink to be obtained from natural resources will provide benefits for the environment, nature, and living creatures. The aim of the study was to promote the use of natural resin in the ink system. Natural Pinus pinaster resin was added into vegetable and mineral oil-based solvents in pure form with alkyd resin in different amounts and ink varnishes of different combinations were prepared. Then, printing inks were produced from these varnishes in pure and hybrid form. Following the assessment of the rheological properties of the inks prepared, printing tests were conducted to assess the printing quality parameters. Ideal mixing ratios of the natural resins in the ink were determined for printability. The environmental importance and advantages of the use of natural resins were discussed. Recommendations were given in line with the results to encourage widespread use of natural resins in near future. 相似文献
5.
6.
Özge Seçmeler Özlem Güçlü Üstündağ 《International Journal of Food Science & Technology》2019,54(5):1609-1616
The partitioning of predominant lipophilic olive bioactives (squalene, β-sitosterol and α-tocopherol) in olive oil processing was studied for the first time using common integrated olive milling plant. 7% of the oil and 5% of the squalene present in the olives was lost in the last pomace. β-sitosterol and α-tocopherol, which are mainly concentrated in the seed of the olive fruit, was recovered in virgin olive oil to a lesser extent (66%, 67%) while 10% were lost in last pomace. Thus, the loss of β-sitosterol and α-tocopherol was higher than that of squalene and oil, due to nonrecovered bound forms. 19% of the α-tocopherol and 21% of the β-sitosterol loss was unaccounted for, which can be attributed to degradation of α-tocopherol and incomplete recovery of sterols from the olive and pomace matrices. This study provides a basis for process development studies. 相似文献
7.
Ülo Lepik 《International Journal of Impact Engineering》1985,3(2):77-91
A shape optimization method for elastic beams with segmentwise constant height is proposed. The ends of the beam are simply supported, clamped or free. Two problems are discussed; (i) a beam is loaded by lateral pressure, (ii) a beam is struck by an attached mass. External loads and volume of the beam are prescribed and the deflection in a given cross-section is to be minimized. For solving this problem, the deflections are expanded into a Fourier series by eigenfunctions. Numerical results are given for two-, three- and four-stepped beams. 相似文献
8.
Erdem Bilgili zzet Cem Gknar Osman Nuri Ucan 《International Journal of Circuit Theory and Applications》2005,33(5):393-417
This paper presents a cellular neural network (CNN) scheme employing a new non‐linear activation function, called trapezoidal activation function (TAF). The new CNN structure can classify linearly non‐separable data points and realize Boolean operations (including eXclusive OR) by using only a single‐layer CNN. In order to simplify the stability analysis, a feedback matrix W is defined as a function of the feedback template A and 2D equations are converted to 1D equations. The stability conditions of CNN with TAF are investigated and a sufficient condition for the existence of a unique equilibrium and global asymptotic stability is derived. By processing several examples of synthetic images, the analytically derived stability condition is also confirmed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
9.
The Journal of Supercomputing - In recent years, deep artificial neural networks can have better forecasting performance than many other artificial neural networks. The long short-term memory... 相似文献
10.
工业用地是城市建设用地的主要类型之一,是海绵城市建设的重要区域。通过梳理工业项目硬化面积高、径流污染程度高等特征,针对性提出其海绵城市建设的实施路径、建设标准和技术应用等实施建议。工业项目的海绵城市设计应遵循因地制宜的原则,应合理布局绿地并建设海绵设施,通过精细化的标高设计进行径流组织设计;对于降雨径流污染严重的三类工业项目,其海绵措施应以雨水调蓄池(应急事故池)为主,严禁设置具有渗透功能的源头控制设施。对于三类工业项目,海绵城市所提出的年径流总量控制率的目标与事故池的环保要求基本一致,建议相关部门在制定(修订)的应急事故池设计标准时,其中的径流污染控制体积可与对应区域年径流总量控制率标准协同一致。 相似文献