全文获取类型
收费全文 | 110篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 4篇 |
综合类 | 10篇 |
化学工业 | 4篇 |
金属工艺 | 21篇 |
机械仪表 | 11篇 |
建筑科学 | 5篇 |
轻工业 | 30篇 |
水利工程 | 2篇 |
无线电 | 3篇 |
一般工业技术 | 15篇 |
冶金工业 | 3篇 |
原子能技术 | 2篇 |
自动化技术 | 5篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2017年 | 1篇 |
2015年 | 3篇 |
2014年 | 11篇 |
2013年 | 17篇 |
2012年 | 12篇 |
2011年 | 12篇 |
2010年 | 12篇 |
2009年 | 10篇 |
2008年 | 4篇 |
2007年 | 1篇 |
2006年 | 5篇 |
2004年 | 2篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1995年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1967年 | 2篇 |
1958年 | 1篇 |
排序方式: 共有115条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
LEE Jeung-Hoon JUNG Jae-Kwon LEE Kyung-Jun HAN Jae-Moon PARK Hyung-Gil SEO Jong-Soo 《水动力学研究与进展(B辑)》2012,24(5):658-667
Tip vortex cavitation noise of marine propeller became primary concerns to reduce hazardous environmental impacts from commercial ship or to keep the underwater surveillance of naval ships. The investigations of the tip vortex and its induced noise are normally conducted through the model test in a water cavitation tunnel. However the Reynolds number of model-test is much smaller than that of the full-scale, which subsequently results in the difference of tip vortex cavitation inception. Hence, the scaling law between model-and full-scales needs to be identified prior to the prediction and assessment of propeller noise in full scale. From previous researches, it is generally known that the incipient caivtation number of tip vortex can be represented as a power of the Reynolds number. However, the power exponent for scaling, which is the main focus of this research, has not been clearly studied yet. This paper deals with the estimation of scaling exponent based on tip vortex cavitation inception test in both full-and model-scale ships. Acoustical measurements as well as several kind of signal processing technique for an inception criterion suggest the scaling exponent as 0.30. The scaling value proposed in this study shows slight difference to the one of most recent research. Besides, extrapolation of model-ship noise measurement using the proposed one predicts the full-scale noise measurement with an acceptable discrepancy. 相似文献
6.
The effective parameters on the diameter of carbon nanotubes (CNTs) by plasma enhanced chemical vapor deposition (PECVD) were presented.Among lots of influential parameters,the effects of the catalytic film thickness and the pretreatment plasma power on the growth of CNTs were investigated.The results show that the size of catalytic islands increases by increasing the thickness of catalytic layer,but the density of CNTs decreases.The pretreatment duration time of 30 s is the optimal condition for growing CNTs with about 50 nm in diameter.By increasing the pretreatment plasma power,the diameter of CNTs decreases gradually.However,the diameter of CNTs does not change drastically from 80 to 120 W.The uniformly grown CNTs with the diameter of 50 nm are obtained at the pretreatment plasma power of 100 W. 相似文献
7.
8.
9.
The modified "flame brushing" technique has been used to manufacture microwires and nanowires from both silica and compound glasses. In this paper, the properties of the wires manufactured by this technique are presented. Applications fabricated from microwires are also discussed. 相似文献
10.
The effects of 0, 1.0, 2.0 and 4.0 (x 10?3 M) α-, γ- or δ-tocopherol on chlorophyll b photosensitized oxidation of soybean oil in methylene chloride were studied by peroxide values and headspace oxygen. As concentrations of tocopherols increased, peroxide values decreased and headspace oxygen increased (P < 0.05). At 1.0 × 10?3 M, α-tocopherol showed highest antioxidant effect, γ-tocopherol second and then δ-tocopherol. α- and -γ-Tocopherols had similar effects and δ-tocopherol had lower effect at 2.0 × 10?3 M (P < 0.05). However, the three tocopherols were not different (P > 0.05) at 4.0 × 10?3 M. α-Tocopherol quenched singlet oxygen to reduce the photosensitized oxidation of oil. The quenching rate constants of α-tocopherol were 2.7 × 107M?1sec?1 by peroxide value and 2.6 × 107 M?1sec?1 by headspace oxygen. 相似文献