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41.
主要研究了纳米TiO2的加入对内墙涂料性能的影响。结果表明,加入2%纳米TiO2能极大地提高涂料降解甲醛的能力,但加入4%纳米TiO2反而使涂料的性能变差。涂料的常规性能研究也表明,加入少于2%的纳米TiO2对涂料的常规性能会有极大的提高。 相似文献
42.
A numerical solution is carried out to treat the transient cooling problem with conduction and radiation for a hot spherical body covered with a cold coating material. The solution includes the equations of radiative transfer, coupled with a transient energy equation that contains both radiative and conductive terms. The radiative transfer equation was solved by the discrete ordinates method, and a parmetric study was performed by changing various physical parameters such as the optical thicknesses, thermal conductivity of the coating, emissivity, and diffusivity of the sphere. It was found that the properties of the coating have a direct effect on the cooling rate of the sphere. 相似文献
43.
44.
Bukhanovskii V. V. Borisenko V. A. Kharchenko V. K. Mamuzic I. 《Strength of Materials》2004,36(2):195-202
Experimental data on the short-term strength and plasticity of niobium alloy 5VMTs of the system Nb–W–Mo–Zr in its initial state, after annealing, and with a silicide-ceramic protective coating obtained by testing in vacuum, an inert atmosphere, and in air in the temperature range from 290 to 2270 K are analyzed. The process of microcrack initiation and propagation in the protective coating and matrix is investigated in high-temperature static tension. The limiting plastic strain values have been established at which the composite retains its load-carrying capacity in high- temperature aggressive and oxidizing gas atmospheres. 相似文献
45.
Studies using thin boron carbide (B4C) coatings have previously been performed in order to investigate their potential use as finite-life run-in coatings. Such coatings have been shown to polish the mating surface in a relatively short time. The inherent ability of these coatings to polish can potentially allow them to function as finite-life run-in coatings. Employing such coatings requires a thorough understanding of the parameters which directly influence the changes that occur in the coating abrasiveness throughout the duration of the polishing process. In past studies, changes in the coating abrasiveness during dry sliding wear under ambient conditions have been investigated. However, both lubrication and humidity can strongly influence the abrasive wear process. In this study, the influences of the operating environment, namely humidity and lubrication, on the coating abrasiveness are directly investigated. The coating abrasiveness decreases at a slower rate when a lubricant is added and when the humidity decreases. 相似文献
46.
选用石英粉为耐火骨料,酸式磷酸盐为粘结剂,通过正交试验确定了铸铁件消失模水基涂料的最佳配比。经测试和生产验证,其性能良好,能很好地适应生产要求。 相似文献
47.
以NiSO4·6H2O、CoSO4·7H2O、MnSO4·H2O、NH3·H2O及NaOH为原料,采用共沉淀方法在LiNi0.8 C00.15 Al0.05 (OH)2球形粒子表面包覆一层Ni1/3 Co1/3Mn1/3(OH)2三元材料前驱体,配锂后在750℃下、氧气气氛中焙烧12 h,合成复合层状材料Li[(Ni0.8 Co0.15Al0.05)0.97(Ni1/3Co1/3Mn1/3)0.03]O2.复合层状材料具有核壳结构,包覆壳层的厚度约为1μm.复合层状材料在2.8~4.3 V充放电,0.1C首次放电比容量为188.2 mAh/g;0.2 C循环100次的容量保持率为96.2%;在55℃下以0.2C循环100次,放电比容量保持在163.2 mAh/g. 相似文献
48.
X.J. Wang 《Thin solid films》2006,515(4):1573-1578
Electropolymerization of poly(3,4-ethylenedioxythiophene) (PEDOT) films on indium tin oxide (ITO), using a very thin PEDOT:poly(styrene sulfonate) (PEDOT:PSS) film as a base coating, was carried out in a non-aqueous solution containing the monomer, an electrolyte and propylene carbonate by a two-electrode system. For comparison, PEDOT film electrodeposited on bare ITO substrate under the same condition was also presented. The PEDOT films deposited on these two substrates were characterized by scanning electron microscopy, energy disperse X-ray spectroscopy and Raman spectroscopy. The results indicate that the PEDOT film electrodeposited on bare ITO was not uniform, while the PEDOT film electrodeposited on PEDOT:PSS/ITO has better uniformity. The compositions of the different regions of PEDOT film electrodeposited on bare ITO and PEDOT:PSS/ITO were studied and discussed. Electrochromic devices (ECDs) based on PEDOT films electrodeposited on bare ITO and PEDOT:PSS/ITO were fabricated and characterized by UV-Vis-NIR spectrophotometric study. The results show that the display contrast of the ECD based on PEDOT film electrodeposited on PEDOT:PSS/ITO was improved over that on a bare ITO substrate. 相似文献
49.
C/C复合材料使用后由于氧化表面硬度有不同程度的下降。经再次防氧化处理后,测试了表面硬度及抗氧化性能。结果表明:氧化后C/C复合材料试样的表面肖氏硬度为HS70时,再次防氧化处理后,其表面硬度增至HS80,在700℃恒温静态氧化条件下,氧化失重率分别为0.44%/15h,1.2%/22h,其抗氧化性能最强。表面硬度为HS40的C/C复合材料试样,距表层1mm深度范围内其硬度均低于基底,再次防氧化处理后其硬度值从HS40增至HS60,其700℃抗氧化性能最差,氧化失重率分别为3.93%/15h,6.52%/22h。 相似文献
50.