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181.
Nano-hardness (Hnano) and nano-elastic modulus (Enano) of corroded coating surface layer were investigated using nano-indentation after epoxy coated specimens were immersed in 5% NaCl solution. The penetration depths (d) of corrosive media into epoxy coating were calculated fitting the curves of (H/E)nano vs. indentation depth (h). EIS spectra of epoxy coated specimens immersed in 5% NaCl solution for different time were measured. Finally the relationship of capacitance (Cf,T) of corroded epoxy coating with the penetration depth of corrosive media was studied. The experimental results showed that the transportation process of corrosive media into epoxy coating was studied through the profiles of (H/E)nano with indentation depth. The penetration depth of corrosive media into the epoxy coating increases rapidly with immersed time firstly, and then increases slowly. The capacitance of corroded epoxy coating has a linear function relationship with the penetration depth of corrosive media into epoxy coating. Nano-indentation can be used to study the transportation process of corrosive media into organic coating. 相似文献
182.
For the purpose of obtaining fully dense B4C with micro hole array of high quality and precision, synthesis of B4C powders were carried out by micro powder injection molding. Five kinds of additive systems were used and their influences on mechanical properties were investigated. The relative density, Vickers hardness, bending strength, and fracture toughness of the B4C ceramics with BS10AY additive sintered at 2000 °C for 2 h could reach 97.56%, 3580.4 HV, 355.3 MPa and 5.87 MPa m1/2, respectively. The temperature was generally 100–200 °C lower than reported temperatures which was attributed to the additives. The improvement in mechanical properties was attributed to grain refinement. A mixture of intragranular and transgranular fractures occurred due to the fine microstructures and the additive systems in the B4C ceramics after sintering. Micro-hole array with the diameter of 450 μm and the length-diameter ratio of more than 8 were obtained. The inhomogeneous filling of feedstock from the substrate to the thin wall between two adjacent micro holes caused the inhomogeneous shrinkage of the substrate and micro holes. 相似文献
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色酚AS类颜料是由2-羟基-3-萘酰胺化合物作为偶合组分与取代基芳胺重氮盐偶合制得的偶氮颜料,主要给出红色谱,颜料分子中因含有甲酰氮基(-CONH-)具有良好的耐溶剂性能.文中介绍色酚AS偶氮颜料的发展历史、化学性质及生产、性能、应用,并介绍了目前市场上的二组商用色酚AS偶氮颜料,色酚AS偶氮颜料中红1 12、146以及170在传统工业领域的红色谱中具有相当的市场份额. 相似文献
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Zhang Guangxin Wang Xingping Pei Jindong 《化工生产与技术》2014,(5):I0002-I0005
The article briefly introduced the influence factors of polymer product mold failure; noted that the effect of surface protecting of the mold was better than improving the surface hardness. Pointed out the release agents had a few shortcomings like single function so could not meet the development of modern industry after the release agent usage analysis. Analyzed three fluorine coatings which had obvious advantages: solvent-based, water-based and powder type. Its release mechanism was named as self- layering technology; fluorine coating not only enabled mold to have a smooth release at a complex surface, but itself had a good corrosion resistance, so the environmental protection composite coating is the future trend of industrial surface protection. 相似文献
187.
TiO2由于光催化活性高、价格低廉、无毒等特点受到人们广泛关注。人们将形状不规则粉体TiO2制备成纳米大孔空心球等形状,以提高催化剂的悬浮性能和回收性能。同时,为了进一步提高TiO2对有机废水的光催化降解性能,对TiO2进行了掺杂改性的研究。文章主要介绍了掺杂改性大孔TiO2在光催化降解有机废水中的研究。 相似文献
188.
文章主要介绍一种延期精度高的工业雷管用点火药的设计研究,并与国内普遍使用的工业雷管用点火药进行了比较,设计主要包括提高发火可靠性、提高抗水性能、装配等关键技术的解决方法,从而提高雷管在爆破工程中的延期精度,并降低爆破成本。符合《民用爆炸物品行业技术进步的指导意见》(工信部安[2010]227号)精神的要求。 相似文献
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190.
The present work focuses on the development of functional polyurethane hybrids through the incorporation of surface modified TiO2 nanoparticles. For improving the nano-particle dispersion and increasing possible interactions between nano-particles and polyurethane matrix, the surface of the nano-particles was modified with 1,3,5-triazine core silane coupling agent. The surface modification of nanoparticles was confirmed by FESEM, FT-IR and Raman spectroscopic techniques. The functionalized nanoparticles were then inscribed in 0, 1 and 2 weight percentages into polyurethane matrix. The as prepared composite coatings were investigated for various anti-microbial, thermo-mechanical and anticorrosive properties. The tensile strength of polyurethane was improved by 300 % upon addition of 2 wt% of modified TiO2 nanoparticles as compared to neat polyurethane. Fog test and electrochemical polarization studies suggest that the corrosion resistance increases with increase of the modified TiO2 content in the coating formulation. The composite coatings also have good resistance towards various bacterial and fungal stains as compared to the pure polyurethanes. The coatings substantially gain hydrophilic nature symbiotically with TiO2 content suggesting its potential application as self-cleanable material. 相似文献