全文获取类型
收费全文 | 1073篇 |
免费 | 29篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 6篇 |
综合类 | 5篇 |
化学工业 | 252篇 |
金属工艺 | 20篇 |
机械仪表 | 44篇 |
建筑科学 | 15篇 |
能源动力 | 93篇 |
轻工业 | 55篇 |
水利工程 | 4篇 |
石油天然气 | 12篇 |
无线电 | 94篇 |
一般工业技术 | 205篇 |
冶金工业 | 160篇 |
原子能技术 | 21篇 |
自动化技术 | 120篇 |
出版年
2023年 | 15篇 |
2022年 | 19篇 |
2021年 | 31篇 |
2020年 | 15篇 |
2019年 | 18篇 |
2018年 | 30篇 |
2017年 | 24篇 |
2016年 | 28篇 |
2015年 | 12篇 |
2014年 | 29篇 |
2013年 | 74篇 |
2012年 | 35篇 |
2011年 | 59篇 |
2010年 | 36篇 |
2009年 | 52篇 |
2008年 | 41篇 |
2007年 | 36篇 |
2006年 | 28篇 |
2005年 | 19篇 |
2004年 | 25篇 |
2003年 | 15篇 |
2002年 | 22篇 |
2001年 | 22篇 |
2000年 | 8篇 |
1999年 | 10篇 |
1998年 | 39篇 |
1997年 | 24篇 |
1996年 | 28篇 |
1995年 | 19篇 |
1994年 | 13篇 |
1993年 | 29篇 |
1992年 | 15篇 |
1991年 | 15篇 |
1990年 | 15篇 |
1989年 | 11篇 |
1988年 | 14篇 |
1987年 | 13篇 |
1986年 | 16篇 |
1985年 | 22篇 |
1984年 | 17篇 |
1983年 | 14篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 10篇 |
1978年 | 14篇 |
1977年 | 8篇 |
1976年 | 13篇 |
1973年 | 8篇 |
1971年 | 6篇 |
排序方式: 共有1106条查询结果,搜索用时 11 毫秒
51.
Binary liquid-liquid-equilibria data for several aniline-paraffin and furfural-paraffin systems have been taken. These data along with data for other aniline-hydrocarbon and furfural-hydrocarbon systems from literature have been correlated using UNIFAC model. The UNIFAC group interaction parameters have been found to have a linear temperature dependence. The CH2 groups in cyclo and non cyclo paraffins require different interaction parameters. It was also found that a scaling of the combinatorial term is necessary for higher molecular weight hydrocarbons. 相似文献
52.
Effective thermal conductivities of powder-filled epoxy composites were experimentally obtained using a transient method. Fillers used were aluminum and cupric oxide. Comparisons of these data with published correlations indicate that Agari's model can give better fits. Nielsen's model may also give a good prediction of the shape of particles can be determined and values of parameters A and ?m are available. An alternative method of dealing with parameter C2 in Agari's model is suggested. © 1993 John Wiley & Sons, Inc. 相似文献
53.
The constitutive response and deformation mechanisms in refractory metals with a hexagonal close packed (hcp) crystal structure are reviewed. The research focuses on the high-strain-rate stress-strain response under uniaxial compressive loading and the associated microstructural deformation mechanisms. Some aspects relating to dynamic failure such as adiabatic shear banding in refractory metals and subsequent failure processes are also discussed. 相似文献
54.
55.
56.
Interfacial tension is unique in the sense that it relates to the interface between two immiscible fluid phases. Hence, interfacial tension between the fluid phases can be used to infer a great deal of information about phase equilibria such as solubility, miscibility and mass transfer interactions between the two bulk fluid phases in contact. In this paper, we examine the utility of interfacial tension to characterize miscibility and mass transfer mechanisms in complex hydrocarbon fluids at elevated pressures and temperatures. This study also provides a new method to estimate the dynamic interfacial tension and miscibility by incorporating counter‐directional diffusivities into the traditional Parachor model. 相似文献
57.
双超越离合器式电磁馈能阻尼器原型机试验测试与分析 总被引:2,自引:2,他引:2
在对双超越离合器式电磁馈能阻尼器的前期研究基础上,试制了该阻尼器的原型机,并对谐波激励下原型机的频谱响应特性和阻尼响应特性进行了分析。通过对原型机的测试,证明了该结构方案的可行性,同时还证实了利用转动惯量分力,在被动模式下实现"high-low"半主动阻尼方法的正确性,并为展开对双超越离合器结构的进一步研究奠定了基础。 相似文献
58.
This study examined the individual and simultaneous adsorption of SO{in{itx}} (SO{in{it2}}) and NO{in{itx}} (NO-NO{in{it2}})
on activated carbon prepared from waste palm shell. The adsorption process was examined in a fixed bed reactor at low temperatures
(100\2-300\dgC). For individual adsorption without any catalytic activation, SO{in{itx}} showed good adsorption whereas NO{in{itx}}
was very much poor. In the simultaneous adsorption of SO{in{itx}} and NO{in{itx}}, SO{in{itx}} showed greater adsorption affinity
than NO{itx}. For palm shell activated carbon (PSAC) impregnated with metal catalyst (Ni and Ce) the concentration adsorbed
profile showed that the amount of SO{in{itx}} adsorbed decreased regularly, while the amount of the adsorbed NO{in{itx}} increased
irregularly. The properties of the pure and impregnated PSAC were analyzed by BET, SEM and EDX. These investigations indicated
that PSAC impregnated with metal catalyst is the determining factor in the adsorption of SO{in{itx}} and NO{in{itx}} simultaneously.
Supported financially by Yayasan FELDA, Malaysia (Grant No. 6050075) 相似文献
59.
Extraction of the license plate region is the challenging first step in the license plate recognition system. We propose a novel feature fusion concept for plate extraction. The image-feature extraction process is modeled as a feature-detection problem in noise. The geometric features are probabilistically modeled and detected under various detection thresholds. These detection results are then fused within the Bayesian framework to obtain the features for further processing. Along with a probabilistic model, a pixels voting algorithm is also tested through threshold variation. 相似文献
60.
Kumar Akshi Bhatia M. P. S. Sangwan Saurabh Raj 《Multimedia Tools and Applications》2022,81(24):34615-34632
Multimedia Tools and Applications - Microblogs have become a customary news media source in recent times. But as synthetic text or ‘readfakes’ scale up the online disinformation... 相似文献