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多溶剂萃取法精制印楝素的研究 总被引:4,自引:1,他引:3
对比研究了多溶剂萃取法与单溶剂萃取法精制印楝素的效果,并通过正交试验法选择了多溶剂萃取法精制印楝素的最佳试验条件为:萃取溶剂V(二氯甲烷):V(乙酸乙酯)1:5,分相液V(丙酮):V(水)1:1,V(萃取溶剂):V(分相液)10:3,该方法可将乙醇提取物中印楝素的质量分数从 3.68% 提高到 17.76%。多溶剂萃取法是一种简单高效的精制印楝素的方法。 相似文献
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印楝素(azadirachtin)是第一个从印楝Azadirachtaindica种子中分离出来的、目前世界公认的活性最强的植物源昆虫拒食剂,对害虫具有显著的拒食和生长发育抑制作用,印楝素主要存在于印楝种子中,印楝种子中含印楝素可达0.1%~0.9%(w),为了从印楝种子中充分提取印楝素,本文建立了用超临界流体从印楝种子中萃取印楝素的方法,用正交试验优化设计选择萃取条件,最佳萃取条件为:温度35℃,压力30MPa,夹带剂用量每克印楝种子干粉1.5mL甲醇,提取率明显优于溶剂法。 相似文献
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印楝种仁中印楝素微波萃取方法研究 总被引:8,自引:4,他引:8
以家用变频微波炉改造而成的微波化学反应器为主要设备 ,研究了在微波诱导下萃取印楝种仁中印楝素的方法。对微波功率、辐射时间和萃取溶剂等影响微波萃取的条件进行了筛选 ,优化条件为以甲醇为萃取溶剂 ,微波功率 2 80W ,辐射时间 10 0s,溶剂用量 12 0ml。以HPLC法测定萃取物中的印楝素A含量 ,采用HypersilODS (4mm× 2 5 0mm)色谱柱 ,水 乙腈 (6 3∶37)为流动相 ,检测波长 2 18nm ,流速为 1ml/min。将微波萃取法与常规甲醇室温浸提法和加热回流法进行了比较 ,结果表明 ,微波诱导萃取法具有萃取速度快、溶剂用量少、萃取效率高等优点。 相似文献
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溶剂法萃取印楝素的研究进展 总被引:6,自引:0,他引:6
化学农药由于其污染环境、杀伤天敌、残留物对人畜有害而使其应用受到限制,而生物源农药因其安全性越来越被看好。印楝素就是一种从植物中提取的天然杀虫活性物质。溶剂法萃取印楝素工艺分为4类:①先去油,再用极性有机溶剂萃取;②直接用极性有机溶剂萃取;③用烃类溶剂和极性溶剂协同萃取;④用水萃取。4种工艺各有特点,今后溶剂法萃取印楝素工艺应向操作简便、收率高、成本低的方向发展。 相似文献
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M. H. I. Baird 《加拿大化工杂志》1991,69(6):1287-1301
The solvent extraction area is perceived by some chemical engineers as being mature and fully developed. The present review shows that this is not the case. Many chemical engineering problems must be solved before equipment can be confidently designed from first principles. The review also outlines progress in extraction process chemistry, and in new techniques such as membrane extraction. 相似文献
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A mathematical model has been developed to simulate and predict the dynamic behavior of liquid extraction counter current operations in mixer-settler units. Murphree efficiency has been included in the model. The behavior of a multistage glass mixer-settler has been studied under start-up transient conditions. Very good agreement between the simulation results and the experimental findings have been obtained. The simulation results showed that this model can efficiently be used to determine the optimum number of stages, the capacity of each stage, the phase ratio and the time required for each unit to attain steady state conditions. Other controlling parameters in operating such units are investigated. 相似文献
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张文兵 《化学推进剂与高分子材料》2004,2(4):47-48
根据生产实践,总结蒽醌法生产双氧水中影响萃余液中双氧水含量的各种因素,指出萃余液中H2O2超标的危害,找到控制萃余的有效途径。 相似文献
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番茄红素含量测定中提取方法研究 总被引:1,自引:0,他引:1
采用紫外一可见分光光度法测定番茄酱中番茄红素的含量。在提取时间,提取次数,提取剂的选择等方面考察了影响番茄红素测定效果。试验结果表明:影响番茄酱中番茄红素的提取因素主次顺序为:料液比〉混合液〉提取时〉间提取次数:采用乙酸乙酯+乙醇(9+1)做提取剂,料液比为1:2,提取时间为30min.提取次数为1次,为番茄酱中番茄红素测定提取的最优组合。 相似文献
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竹叶黄酮提取分析方法的研究及其新进展 总被引:2,自引:0,他引:2
从竹叶黄酮的基本性质着手,根据其溶解性,显色反应等特性,选取适当的提取方法。综述了五种应用较广泛的提取新方法、新技术,及分析方法,并简要论述了各种新技术和方法的原理以及应用于竹叶黄酮工业生产方面的情况。 相似文献
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Lorenzo RA Carro AM Alvarez-Lorenzo C Concheiro A 《International journal of molecular sciences》2011,12(7):4327-4347
Template removal is a critical step in the preparation of most molecularly imprinted polymers (MIPs). The polymer network itself and the affinity of the imprinted cavities for the template make its removal hard. If there are remaining template molecules in the MIPs, less cavities will be available for rebinding, which decreases efficiency. Furthermore, if template bleeding occurs during analytical applications, errors will arise. Despite the relevance to the MIPs performance, template removal has received scarce attention and is currently the least cost-effective step of the MIP development. Attempts to reach complete template removal may involve the use of too drastic conditions in conventional extraction techniques, resulting in the damage or the collapse of the imprinted cavities. Advances in the extraction techniques in the last decade may provide optimized tools. The aim of this review is to analyze the available data on the efficiency of diverse extraction techniques for template removal, paying attention not only to the removal yield but also to MIPs performance. Such an analysis is expected to be useful for opening a way to rational approaches for template removal (minimizing the costs of solvents and time) instead of the current trial-and-error methods. 相似文献