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排序方式: 共有1358条查询结果,搜索用时 15 毫秒
101.
Joe Liscouski 《Journal of Automated Methods and Management in Chemistry》1997,19(6):199-204
This paper provides some initial considerations into the design and
function of the Data Librarian. The first part (Liscouski, J., 1997, Journal of Automatic Chemistry, 19, 193-197) described the need for the Librarian. 相似文献
102.
Marcus A. Worsley Peter J. Pauzauskie Sergei O. Kucheyev Joseph M. Zaug Alex V. Hamza Joe H. Satcher Theodore F. Baumann 《Acta Materialia》2009,57(17):5131-5136
Here, we present the synthesis and characterization of low-density single-walled carbon nanotube-based aerogels (SWNT-CA). Aerogels with varying nanotube loading (0–55 wt.%) and density (20–350 mg cm?3) were fabricated and characterized by four-probe method, electron microscopy, Raman spectroscopy and nitrogen porosimetry. Several properties of the SWNT-CAs were highly dependent upon nanotube loading. At nanotube loadings of 55 wt.%, shrinkage of the aerogel monoliths during carbonization and drying was almost completely eliminated. Electrical conductivities are improved by an order of magnitude for the SWNT-CA (55 wt.% nanotubes) compared to those of foams without nanotubes. Surface areas as high as 184 m2 g?1 were achieved for SWNT-CAs with greater than 20 wt.% nanotube loading. 相似文献
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The National Health Service in Scotland (NHSScotland) has, in recent years, done much to reduce energy consumption in its major healthcare buildings (hospitals). On average, a reduction of 2% per year has been achieved since 2000, based on hospital buildings. However, there had been little or no attention paid to smaller premises such as health centres, clinics, dentists, etc. Such smaller healthcare buildings in Scotland constitute 29% of the total treated floor area of all NHSScotland buildings and, therefore, may contribute a similar percentage of carbon and other emissions to the environment. By concentrating on a sample of local health centres in Scotland, this paper outlines the creation of an energy benchmark target, which is part of a wider research project to investigate the environmental impacts of small healthcare buildings in Scotland and the scope for improvements. It was found that energy consumption varied widely between different centres but this variation could not be linked to building style, floor area or volume. Overall, it was found that a benchmark of 0.2 GJ/m3 would be challenging, but realistic. 相似文献
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108.
Joe Russ 《计算机光盘软件与应用》2007,(12):108-109
本期,我们邀请了新成立的移动成像公司Wyld Stallyons的Richard May坐客访谈栏目,进一步了解他们为内衣品牌Lascivious制作的颇受好评的病毒式短片The Doll以及他们为MTV、VH1和BMW等客户创作的作品。 相似文献
109.
采用过硫酸盐和几种特别添加剂配制成的微蚀剂,不仅具有传统微蚀剂的优点,而且拥有其独特的优点:微蚀处理的铜表面比传统微蚀剂处理的光亮;微蚀处理后暴露在空气中10 min,铜表面也不变色;微蚀处理后的元件没有原电池腐蚀现象发生;其工作溶液比传统微蚀剂稳定;微蚀速率容易控制以满足不同的微蚀要求;微蚀处理不影响精密线路板和元件的尺寸。 相似文献
110.
Bohyun Hwang Hanmin Park Seonggun Joe Byungkyu Kim 《Advanced Engineering Materials》2023,25(16):2300289
The rapid advancements in 3D printing technologies offer immense design flexibility and the ability to create complex structures with high resolution. Using these cutting-edge technologies and materials (i.e., a polylactic acid and fused deposition modeling), a novel design principle is introduced for a fingerless gripper, achieved through topological optimization. To realize the grasping capabilities, a coiled garter spring made of shape memory alloy (SMA) is incorporated at the end of the flexure beams. Based on the experiments, it is found that the gripper is very quick to respond, taking only 5 s to heat up and 15 s to cool down. This promising performance is achieved by carefully balancing the net force differential between the restoring force of the flexure beam and the force of the SMA coiled garter spring. In addition to its responsiveness, the gripper demonstrates a high force-to-weight ratio of 5.3, allowing it to lift heavy payloads of up to 4.91 N (0.5 kgf) despite its lightweight design (total weight of 94.2 g). Overall, this work showcases the potential of 3D printed fingerless grippers in terms of high holding strength, lightweight, low cost, and simple fabrication. 相似文献