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61.
An-Ke DuQian Zhou Johannes M.N. van Kasteren 《Journal of Analytical and Applied Pyrolysis》2011,92(1):267-272
Thermal degradation of ABS and denitrogenated ABS samples (DABS), prepared by sequential hydrolysis of ABS using PEG/NaOH, has been investigated under inert gas and at atmospheric pressure in a temperature range between 40 and 700 °C, by means of TGA, TGA-IR, and TGA-MS, to study the link between original structure of DABS and eventual pyrolysis. For DABS, thermal decomposition begins at the side groups of -CONH2 and/or -COOH, resulting in a lower initial degradation temperature of DABS (around 330 °C) relative to ABS (372.5 °C). Moreover, less HCN and acrylonitrile evolve from the DABS samples, while the evolution of CO2 starts earlier and becomes more important, in line with the decreased number of -CN groups and the increased number of -COOH functional groups due to hydrolysis. The results from thermo-analytical experiments were confirmed by batch pyrolysis tests: the nitrogen content of oil produced from DABS pyrolysis is much lower, compared with that from ABS, proving that effective denitrogenation of ABS prior to pyrolysis is beneficial to the quality of pyrolysis oil. 相似文献
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Michele Baglioni Giovanna Poggi David Chelazzi Piero Baglioni 《Molecules (Basel, Switzerland)》2021,26(13)
Cultural Heritage is a crucial socioeconomic resource; yet, recurring degradation processes endanger its preservation. Serendipitous approaches in restoration practice need to be replaced by systematically addressing conservation issues through the development of advanced materials for the preservation of the artifacts. In the last few decades, materials and colloid science have provided valid solutions to counteract degradation, and we report here the main highlights in the formulation and application of materials and methodologies for the cleaning, protection and consolidation of works of art. Several types of artifacts are addressed, from murals to canvas paintings, metal objects, and paper artworks, comprising both classic and modern/contemporary art. Systems, such as nanoparticles, gels, nanostructured cleaning fluids, composites, and other functional materials, are reviewed. Future perspectives are also commented, outlining open issues and trends in this challenging and exciting field. 相似文献
64.
提出一种以丙烯腈-丁二烯-苯乙烯(ABS)薄膜作为各向异性腐蚀溶液的掩模的薄膜保护方法。ABs胶以旋涂的方法涂布在硅片表面,然后经过一系列的处理工序以增强膜与衬底的粘附性。本文比较了在不同温度条件下AB8胶膜在KOH和TMAH溶液中的抗腐蚀特性。实验证明:在90℃、25wt%TMAH溶液中,ABS薄膜的掩模时间达到10h左右,而且这种薄膜的优点在于很容易用化学试剂加以去除。 相似文献
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利用MCS-51系列单片机设置慢进值和提前量来实现生产企业自动投料质量的控制,保证了控制精度,提高产品质量。 相似文献
67.
王晖 《电气电子教学学报》2002,24(6):53-54,60
介绍了英国高校电子专业高等数学教学的基本情况,包括课程内容,教学大纲,考核方式和教材等,分析了它的主要特色,供国内同行参考与借鉴。 相似文献
68.
This paper details developments in the CO2 laser cutting of thick ceramic tiles, that is thicknesses of 8.5 mm and 9.2 mm. These tiles were cut at a combination of different cutting speeds to determine the necessary cutting parameters for various tile geometries. Different cutting modes were used in conjunction with different cutting speeds to investigate cut quality after laser processing. The work also looked into the effects on cutting through using various shield gases. Multipass cutting and underwater cutting were performed to examine their effects on thermal load during processing. 相似文献
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