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充发利用山区林资源,调整产业结构,加快林区林化产品的更新换代,追踪国际上近年林化产品的生产新技术、生产新工艺,加大力度调整我省现有的林区的产业结构,提高现有产品的质量档次,拓宽国内外市场占有率. 相似文献
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松脂蒸馏的方法有滴水法、水蒸汽法、导热油法和CO2/N2循环活气法,从能量消耗、过程装备、产品质量以及"三废"排放等方面,对各种松脂蒸馏方法进行比较。结果表明,CO2/N2循环活气法比水蒸汽法节省能量消耗近一倍,减少冷却水用量13.23~16.18m3/t松香;CO2/N2循环活气法蒸馏松脂不需要油水分离器、盐滤器,又因为不需要带走活气的冷凝热,冷凝冷却器的换热面积也减少,也不需要建造大型过热水蒸汽锅炉;CO2/N2循环活气法蒸馏松脂所得的产品不含水份,松香无结晶现象,松节油透明无混浊;而且该法蒸馏松脂无三废产生,克服了水蒸汽法排放含松节油废水、废气和工业废盐的缺点,是一种清洁的生产方法。 相似文献
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Agns Lattuati-Derieux Jean-Philippe Echard Sylvie Thao-Heu Bertrand Lavdrine 《Journal of Cultural Heritage》2010,11(4):1-481
Nicéphore Niépce carried out a lot of meticulous experiments that led him to the invention of photography. In particular, in the 1820s, he obtained heliographs by coating a substrate with a light-sensitive substance, which was then exposed to light under a paper print made translucent with the help of varnish. The objective of the work described here is to determine how Niépce made these paper prints transparent. Did he use his experimental knowledge on photosensitive resins, or did he apply commonly used recipes of his time to make paper transparent? To date, no studies have been carried out on the varnish used by Nicéphore Niépce and no previous research has undertaken analytical investigations on Nicéphore's prints, using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Gas Chromatography/Mass Spectrometry (GC/MS). In this paper, we identify the varnishes used by Nicéphore Niépce on four transparent prints, now belonging to the Nicéphore Niépce museum in Chalon-sur-Saône, France. The varnish he used was based on a diterpenic Pinaceae sp. resin (most probably colophony). The finding is supported by historical knowledge about varnishes. 相似文献
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