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61.
(Ni-P)-纳米Si3N4微粒复合刷镀工艺研究 总被引:10,自引:1,他引:10
论述了(Ni-P)-纳米Si3N4微粒复合刷镀工艺,设备及(Ni-P)-纳米Si3N4微粒复合刷镀液的组成和配制方法;研究了纳米Si3N4微粒在刷镀液中的含量,刷镀工作电压和刷镀温度对(Ni-P)-纳米Si3N4微粒复合刷镀层的影响;研究了在不同的热处理温度下复合刷镀层的硬度和耐磨性。 相似文献
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Olaf Ueberschär Carolin Wagner Tim Stangner Christof Gutsche Friedrich Kremer 《Polymer》2011,52(8):1829-4032
Optical tweezers accomplished with fast position detection enable one to carry out Brownian motion analysis of single DNA-grafted (grafting density: ∼1000 molecules per particle, molecular weight: 4000 bp) colloids in media of varying NaCl concentration. By that the effective hydrodynamic radius of the colloid under study is determined and found to be strongly dependent on the conformation of the grafted DNA chains. Our results compare well both with recent measurements of the pair interaction potential between DNA-grafted colloids (Kegler et al. Phys Rev Lett 2008; 100:118302) and with microfluidic studies (Gutsche et al. Microfluid Nanofluid 2006; 2:381-386). The observed scaling of the brush height with the ion concentration is in full accord with the theoretical predictions by Pincus, Zhulina, Birshtein and Borisov. 相似文献
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一个三维计算机水粉笔刷模型 总被引:12,自引:2,他引:12
提出一个三维计算机水粉笔刷模型,包括笔刷单元选取、颜料模拟、颜料扩散以及整体控制4部分,该模型结构简单开可以直接应用到传统三维曲面上,给了的结果具有手工绘制水粉画的效果,文中图例表明该模型的模拟效果令人满意。 相似文献
66.
图像润饰是一种广泛应用的图像篡改手段。为了对润饰的图像实施盲检测,提出了一种图像盲鉴别算法。该算法首先查找图像中每个分块并把其插入到KD树中,搜索到值相同或最近的粗略匹配块,然后使用位置向量的分层聚类法群集块对消除杂散配对,最后应用7-tap拉普拉斯过滤器并统计可疑块的零连通分量来消除误报,从而定位出精确的润饰篡改区域。实验表明,该方法能有效精确地识别出修复刷对非压缩图像和高品质压缩图像等一类图像的润饰篡改技术的使用。当应用到压缩级别较高的图像时,如果润饰的区域足够大,依然会获得准确的结果。 相似文献
67.
Eylem Turan 《Thin solid films》2010,518(21):5950-310
Thermoresponsive poly(N-isopropylacrylamide) [poly(NIPAM)] brush on silicon wafer surface was prepared by combining the self-assembled monolayer of initiator and atom transfer radical polymerization (ATRP). The resulting polymer brush was characterized by in situ reflectance Fourier transform infrared spectroscopy, atomic force microscopy and ellipsometry techniques. Gel permeation chromatography determination of the number-average molecular weight and polydispersity index of the brush detached from the silicon wafer surface suggested that the surface-initiated ATRP method can provide relatively homogeneous polymer brush. Contact angle measurements exhibited a two-stage increase upon heating over the board temperature range 25-45 °C, which is in contrast to the fact that free poly(NIPAM) homopolymer in aqueous solution exhibits a phase transition at ca. 34 °C within a narrow temperature range. The first de-wetting transition takes place at 27 °C, which can be tentatively attributed to the n-cluster induced collapse of the inner region of poly(NIPAM) brush close to the silicon surface; the second de-wetting transition occurs at 38 °C, which can be attributed to the outer region of poly(NIPAM) brush, possessing much lower chain density compared to that of the inner part. 相似文献
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The growth of the powder coating business is affected by the toxicological effects of the raw materials used in the coating formulation and the saturation of the present market for powder coatings, being limited to general metal applications only. This has a strong influence on the long-term research programmes at both raw materials suppliers and powder paint producers. In the last decade of the 20th century, we witness appearance of several new types of toxicologically-safe powder coating systems on the commercial scale. At the same time, there is strong evidence of efforts to penetrate new market fields where powder coatings are not typically used. This includes the markets for automotive clear top coatings, can and coil coatings, coatings for industrial wood, plastics and paper. The new developments in the chemistry of powder coatings are followed by changes and improvements in the production technology for powder coatings as well as developments of new application techniques. This paper summarises the research work on chemistry, production and application technology of powder coatings and tries to extrapolate the tendencies in the years to come in order to predict the achievements and the impacts on the paint industry. 相似文献
70.
A series of well-defined brush-type amphiphilic polystyrene-g-poly(2-(dimethylamino) ethyl methacrylate)) (PS-g-PDMAEMA) copolymers were successfully synthesized via atom transfer radical polymerization (ATRP), using chloromethylated polystyrene (CMPS) as the macroinitiator. The self-assembly behavior of the resulting brush-type copolymers in deionized water and deionized water/acetone (v/v=2/3) mixture was studied by high performance particle sizer (HPPS). The results showed that the Z-average size of the micelles in deionized water increased with the increase of molecular weight of PDMAEMA, and the corresponding size was larger than that in mixed solvent of deionized water and acetone (v/v=2/3). The morphologies of the micelles self-assembled from PS-g-PDMAEMA in selective solvents were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). When the micelles were prepared in water/acetone (v/v=2/3) mixture and cast them on a glass slide at different temperatures (from 50 up to 200 °C), the transformation of the morphologies of aggregates, from needle-like solid to microcubic particles, was observed using SEM. 相似文献