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二氧化碳的利用和转化是近年来人们普遍关注的研究课题,进行二氧化碳转化成碳的研究,对环境保护和碳资源的再利用有着十分重要的意义。本文对3二氧化碳还原为碳的研究现状进行了综述,并展望了今后此领域研究的发展前景。 相似文献
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利用差示扫描量热仪研究了聚乳酸(PLA)在常压下的等温冷结晶行为,并用偏光显微镜观测了不同温度下等温结晶100 min的PLA样品的结晶形态;以二氧化碳(CO2)为介质,利用高压釜在5 MPa压力、不同温度下制备了冷结晶过程中的等温结晶100 min的PLA样品,分别利用偏光显微镜和广角X射线衍射仪对比了常压和CO2作用下PLA产生的球晶形态和晶型结构。结果表明,CO2对PLA有显著的增塑作用,可以增强PLA分子链的活性,使其在较低的温度下发生冷结晶;与常压相比,PLA在CO2作用下冷结晶形成的球晶尺寸减小球晶数量增加球晶完善程度提高,但最终结晶度降低。 相似文献
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回顾合成气制备的向种途径;评述了甲烷二氧化碳催化重整制合成气的催化剂研究状况,并对催化剂炭和反应机理进行了简单的介绍。 相似文献
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由于CO2等温室气体引发的温室效应对全球生态环境和社会经济发展造成了显著影响,使得CO2减排受到了国际社会的密切关注。文章针对CO2的集中排放源,介绍燃煤电厂烟气中CO2减排技术路线和目前国际上常用的CO2捕集分离技术,最后分析和展望CO2捕集分离技术的发展前景。 相似文献
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Ignacio Medina Jos Luis Martínez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,68(1):14-18
A study of cider dealcoholisation by supercritical extraction with carbon dioxide using pilot-plant-scale equipment has been carried out. The effects of pressure, temperature and solvent to feed ratio have been examined. Supercritical and liquid carbon dioxide have been used to extract ethanol and aromas from cider at pressures of 80–250 bar and temperatures of 20 and 40°C. 相似文献
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The transition of amorphous alumina to α-alumina was studied by X-ray diffraction, electron diffraction, DTA, TGA, and microscopic observation. The amorphous alumina was prepared by condensing vapor from evaporating molten alumina in vacuo onto the glass envelope of the vacuum chamber. The amorphous alumina was transformed to a poorly crystalline material by heating for 16 hr between 570° and 670°C. Between 670° and 1200°C, the poorly crystalline alumina was converted to α-alumina via two parallel series of transition aluminas. The principal series was γ-alumina to δ-alumina to α-alumina. A minor amount of θ-alumina developed from the initial crystallization and persisted throughout the duration of the principal series as a parallel path. Some conversion of δ- to θ-alumina was detected above 900°C. DTA produced an unexplained exothermic peak at 320°C and a second exothermic peak at 860°C which corresponded to formation of metastable aluminas. 相似文献
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