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101.
Model epoxy and bismaleimide compounds in thin film form were used to simulate epoxy and bismaleimide composite surfaces, in order to study compositional changes and interfacial reactions induced by oxygen plasma treatment. X-ray photoelectron spectroscopy (XPS) and infrared reflection-absorption spectroscopy (IR-RAS) were used to probe chemical changes which occurred. XPS and IR-RAS were found to be complementary techniques in determining the nature of functional groups incorporated into surfaces by plasma treatment. IR-RAS analysis of the model surfaces following exposure to a liquid epoxy resin revealed that while adsorption of the liquid epoxy occurred on both plasma-treated and nonplasma-treated surfaces, the oxygen plasma-treated surface alone was capable of initiating ring-opening reactions in the epoxy. However, this effect was not observed unless immediate contact was made between the plasma-treated surface and the liquid epoxy resin, illustrating the short-lived reactivity of the functional groups on the plasma-treated surface. 相似文献
102.
基于红外光谱吸收原理,设计了一种单光源单光路的在线分析仪。在实验室环境下,利用SO2进行实验,并对实验结果进行分析。实验结果表明:该分析仪具有很好的准确性、重复性和稳定性,实现了多种气体的在线测量。 相似文献
103.
Durability of adhesive bonds formed by curing epoxies against oil-contaminated steel substrates using amidoamine curing agents was determined during exposure to boiling water. The most durable bonds were obtained using amidoamine curing agents with relatively low amine numbers and by blending silane coupling agents such as γ-glycidoxypropyltrimethoxysilane (γ-GPS) and N-(2-aminoethyl)-3-aminopropyltrimethoxy silane (AAMS) into the adhesives. When X-ray photoelectron spectroscopy (XPS) was used to characterize the failure surfaces of the adhesive joints after exposure to boiling water, it was determined that adhesives prepared using amidoamine curing agents with low amine numbers were able to displace the oil from the steel surface but adhesives prepared with amidoamine curing agents with high amine numbers were not. Results obtained from XPS also showed that the amino groups on the substrate fracture surfaces of joints prepared using curing agents with low amine numbers were protonated whereas the amino groups in the bulk adhesive were not, indicating that there was a chemical interaction between the curing agent and the hydrated surface of the substrate. It was also shown using infrared spectroscopy that the amidoamine curing agents formed salts with calcium compounds in the oil. 相似文献
104.
105.
涂料原料和涂层厚度对反射隔热保温性能影响研究 总被引:8,自引:0,他引:8
通过研究涂料配方中所用乳液、颜料、常规填料和隔热填料在红外灯下的反射、隔热和保温性能,发现高折射率的二氧化钛和含有微孔的硅藻土具有最佳的反射和隔热保温效果,轻质碳酸钙和重质碳酸钙具有一定的隔热保温作用,而理论上具有隔热保温效果的填料海泡石等并没有预期的效果。涂层厚度对隔热保温效果具有一定影响,但是没有颜料和填料的影响大。隔热涂料使用的填料应含有硅藻土、二氧化钛以及一些常规的填料。 相似文献
106.
107.
采用0.5μm标准CMOS工艺和微机械加工工艺,设计并制作了低成本4×4钨微测辐射热计阵列集成芯片。阵列中每个钨微测辐射热计均由微悬桥结构和钨热敏电阻组成,CMOS读出电路集成在阵列下方。微悬桥结构由表面牺牲层技术实现,不需要任何的光刻工艺。钨微测辐射热计像元尺寸为100μm×100μm,填充因子为20%。测试结果表明,在真空环境下,钨微测辐射热计等效热导为1.31×10-4W/K,等效热容为1.74×10-7J/K,热时间常数为1.33 ms。当红外光源的斩波频率为10 Hz时,钨微测辐射热计的电压响应率为1.91×103V/W,探测率为1.88×107cm·Hz1/2/W。 相似文献
108.
109.
介绍了红外线气体分析仪的测量原理以及在合成氨装置中的应用情况。对 使用中出现的故障和原因进行了分析,对预处理装置的改造提出了相应的措施。 相似文献
110.
Linear low‐density polyethylene (LLDPE), based on butene‐1 or hexene‐1, was irradiated with γ‐rays under vacuum or in the presence of air. The study focused on the influence of the dose rate and the γ‐dose on the thermal properties of LLDPE. Differential scanning calorimetry, thermogravimetric analysis (TGA), and TGA/FTIR techniques were used to address the thermal behavior as a result of γ‐irradiation. During this irradiation, competition between crosslinking and scission reactions, subsequent to oxidation reactions, occurred in the polymeric material, which strongly depends on the experimental conditions. A decrease of the crystallinity for γ‐irradiated samples was observed in particular for samples irradiated under vacuum. This observation may be explained by increased hindrance of segment mobility due to crosslinking reactions that prevent crystal growth. TGA investigations revealed an enhancement of the thermal stability for samples irradiated under vacuum but not for those irradiated in air. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2790–2795, 2006 相似文献