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91.
Shaofeng Wang Yuan Hu Zhihua Lin Zhou Gui Zhengzhou Wang Zuyao Chen Weicheng Fan 《Polymer International》2003,52(6):1045-1049
Acrylonitrile–butadiene–styrene (ABS)/montmorillonite nanocomposites have been prepared using a direct melt intercalation technique by blending ABS and organophilic clay of two different particle sizes: OMTa (5 µm) and OMTb (38 µm). Their structure and flammability properties were characterized by X‐ray diffraction, high resolution electronic microscopy (HREM), thermogravimetric analysis (TGA) and cone calorimeter experiments. The results of HREM showed that ABS/5 wt% OMTa nanocomposite was a kind of intercalated–delaminated structure, while ABS/5 wt% OMTb nanocomposite was mainly an intercalated structure. The nanocomposites showed a lower heat release rate peak and higher thermal stability than the original ABS by TGA and cone calorimeter experiments. Also, the intercalated nanocomposite was more effective than an exfoliated–intercalated nanocomposite in fire retardancy. Copyright © 2003 Society of Chemical Industry 相似文献
92.
Frantz Rowe 《欧洲信息系统杂志》2006,15(3):244-248
93.
周庆民 《现代制造技术与装备》2003,(1):41-42
建厂已近60年的博山电机厂,在企业发展的历史上曾经有过辉煌:40年代,作为军工厂,在抗日战争的烽火和解放战争的硝烟中为新中国的解放事业做出了很大的贡献;50年代,作为全国八大电机厂之一,又为新中国的建设事业提供了许多优良的产品,而且作为汽车电机、直流微电机、交流 相似文献
94.
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96.
Yang Lüyun 《中国稀土学报(英文版)》2006,24(Z2)
The fabrication of one kind of large core area Nd3 doped silicate glass photonic crystal fiber, and demonstration of the fiber's waveguidence properties were reported. This fiber owns a random air hole distribution in the cladding. The measured minimum loss of this kind of fiber is 10 dB·m-1 at 660 nm. These fibers can sustain only a single mode at least over wavelength ranging from 660 nm to 980 nm. 相似文献
97.
PURPOSE: To evaluate the accuracy of measuring intraocular pressure by handheld non-contact applanation tonometer. METHOD: 58 patients' (113 eyes) intraocular pressure were measured by Keeler, non-contact tonometer and R 900 Goldmann applanation tonometer and the results of measurement of intraocular pressure by the two kinds of tonometers were compared. RESULT: The mean intraocular pressure measured by non-contact is 16.31 +/- 5.59 mmHg and 17.49 +/- 6.13 mmHg (1 mmHg = 0.1333 kPa) by Goldmann applanation tonometer, respectively. There was no statistical significance to be found (P > 0.05) between the two methods. By linear correlation and regression analysis, a positive correlation was found between the two methods (r = 0.8942, b = 0.8154). CONCLUSION: The handheld non-contact tonometer has the same accuracy and reliability of measurement of intraocular pressure comparing with Goldmann applanation tonometer, and it can be used in glaucoma clinic and screening. 相似文献
98.
锆(Ⅳ)-3,5-diBr-PADAP-安替比林三元配合物的分光光度研究与应用 总被引:1,自引:0,他引:1
本文提出在安替比林存在下,以3,5-diBr-PADAP为显色剂,分光光度测定微量锆的新方法。在pH1~2的HCl介质中,锆(W)与试剂和安替比林形成配合比为1:1:1的红色三元配合物,最大吸收值在615nm波长处,摩尔吸光系数ε=1.35×10~5。锆(Ⅳ)量在0~25μg/25ml范围内,遵守比尔定律。方法简单、快速、准确。若采用钽试剂—苯萃取法分离共存离子,可适用于钽铌矿和合金中痕量锆的测定。 相似文献
99.
100.
Barbara K. Reck Robert B. Gordon 《JOM Journal of the Minerals, Metals and Materials Society》2008,60(7):55-59
Nickel and chromium are essential ingredients in alloys increasingly important for energy-efficient, environmentally friendly
modern technology. Quantitative assessment of the flows of these metals through the world economy from resource extraction
to final disposal informs resource policy, energy planning, environmental science, and waste management. This article summarizes
the worldwide technological cycles of nickel and chromium in 2000. Stainless steel is the major use of these metals, but they
serve numerous other special needs, as in superalloys for high-temperature service, as plating materials, and in coinage.
Because they are used primarily in alloys, novel recycling issues arise as their use becomes more widespread.
“... the great New York and St. Louis double track, nickel plated railroad...”
— Norwalk, Ohio, Chronicle 10 March 1881 announces arrival of surveyors for the future Nickel Plate Railway
“Later [1911] I formed an alloy of Iron and Chromium, which showed remarkable resistance to rust and tarnish ... [It was]
rediscovered by an Englishman named Brearley, in 1914.”
—Elwood Haynes to Stephen F. Roberts, 17 January 1925 相似文献