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81.
硅丙涂料的现状及发展趋势 总被引:4,自引:0,他引:4
介绍了硅丙涂料在国内外市场的生产及需求现状,指出了硅丙涂料产品的发展方向。 相似文献
82.
Low-Thermal-Conductivity Rare-Earth Zirconates for Potential Thermal-Barrier-Coating Applications 总被引:9,自引:0,他引:9
Jie Wu Xuezheng Wei Nitin P. Padture Paul G. Klemens Maurice Gell Eugenio García Pilar Miranzo Maria I. Osendi 《Journal of the American Ceramic Society》2002,85(12):3031-3035
Rare-earth zirconates have been identified as a class of low-thermal-conductivity ceramics for possible use in thermal barrier coatings (TBCs) for gas-turbine engine applications. To document and compare the thermal conductivities of important rare-earth zirconates, we have measured the thermal conductivities of the following hot-pressed ceramics: (i) Gd2 Zr2 O7 (pyrochlore phase), (ii) Gd2 Zr2 O7 (fluorite phase), (iii) Gd2.58 Zr1.57 O7 (fluorite phase), (iv) Nd2 Zr2 O7 (pyrochlore phase), and (v) Sm2 Zr2 O7 (pyrochlore phase). We have also measured the thermal conductivity of pressureless-sintered 7 wt% yttria-stabilized zirconia (7YSZ)—the commonly used composition in current TBCs. All rare-earth zirconates investigated here showed nearly identical thermal conductivities, all of which were ∼30% lower than the thermal conductivity of 7YSZ in the temperature range 25°–700°C. This finding is discussed qualitatively with reference to thermal-conductivity theory. 相似文献
83.
通过选用透明度高、太阳能吸收率高的丙烯酸树脂和高亮度、长余辉时间的镝和铕稀土离子共掺杂的稀土硅酸盐光致发光粉末材料aCaO·bZnO·cBaO·dMgO·nSiO2:Eu,Dy,制备出了具有较强的蓄光能力和较长发光时间的夜光涂料,并论述了其制备方法和特性。 相似文献
84.
85.
The force needed to pull a cylindrical stud from a soft elastomeric film depends on their elastic and geometric properties. For a rigid stud and a thick elastomeric film, the pull-off stress (σ) depends on the elastic modulus (E) of the film and the radius (a) of the stud as σ ∼ (E/a)1/2 (soft adhesion). However, when the film is very thin, the pull-off stress is significantly higher than the case with thick films, and its value depends on the elastic modulus and the thickness (h) of the film as σ ∼ (E/h)1/2 (hard adhesion). Here, we study the pull-off behavior of a soft cylindrical stud, one flat end of which is coated with a high modulus thin baseplate. As the flexural rigidity of this baseplate is varied, we observe the transition between the two types of adhesion. We present a simple physical interpretation of the problem, which could be of value in understanding various biofouling and adhesive situations. 相似文献
86.
Summary: A semi‐batch process using nitroxide mediated polymerization, was explored for the design of low molecular weight solvent‐borne coatings, typical of those used in the automotive industry. While living radical polymerization (LRP) offers many advantages in the control of polymer chain microstructure that may confer important physical and chemical property benefits to coatings, adapting LRP to a semi‐batch process poses significant challenges in the design and operation of the process. Using styrene monomer, various two‐component initiating systems (free radical initiator, 4‐hydroxy‐TEMPO) were studied to understand the effects of different initiators on the course of polymerization. In addition, an alkoxyamine was synthesized and used as the initiating source. The initiators Luperox 7M75 and Luperox 231 give higher polymerization rates and reasonable control over polymerization, while benzoyl peroxide (BPO), Vazo 67, and the alkoxyamine are less effective. The number of polymer chains in the final product is always less than the theoretical value, reflecting poor initiation efficiency, probably resulting from undesirable termination reactions that become important due to the nature of the semi‐batch process. Adding camphorsulfonic acid (CSA) or charging initiator concurrently with monomer during semi‐batch feed, can increase the polymerization rate while maintaining the living character of the polymerization. The copolymerization of styrene and butyl acrylate is also shown to exhibit living character.
87.
介绍了环保型反应性乳化剂ADEKA?REASOAP?SR-10、ER-30的结构和特性,重点分析了反应性乳化剂在水性木器乳液聚合中的应用及其对聚合物性能的影响。实验证明,应用反应性乳化剂所得的聚合物性能要远远优于非反应性乳化剂所得聚合物性能,而且应用了非离子反应性乳化剂所得的聚合物性能要优于单独使用阴离子反应性乳化剂所得聚合物性能。最后预测了环保型反应性乳化剂的良好应用前景。 相似文献
89.
90.