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以艾叶挥发油提取率为考核指标,采用单因素实验考察浸泡时间、料液比、提取时间等对艾叶挥发油提取率的影响,在此基础上,采用响应面法优化艾叶挥发油的共水蒸馏提取工艺,并通过紫外分光光度法测定艾叶挥发油对DPPH自由基的清除率来评价其抗氧化性能。结果表明,艾叶挥发油的最佳提取工艺条件为:浸泡时间1.5 h、料液比1∶10(g∶mL)、提取时间4.5 h,在此条件下,艾叶挥发油提取率最高,为0.83%。当艾叶挥发油浓度为80 mg·mL~(-1)时,DPPH自由基清除率最高,为39.12%。表明艾叶挥发油具有一定的抗氧化活性。 相似文献
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利用响应面分析法优化超声波辅助提取五桠果叶木姜子挥发油的工艺条件。以提取的料液比、提取时间、提取温度为随机因子,在单因素试验的基础上,进行三因素三水平的Box-Behnken中心组合设计,采用响应面分析(Response surface analysis methodology)三个因素以及因素彼此间的交互作用对五桠果叶木姜子挥发油提取率的影响。结果超声波法提取五桠果叶木姜子挥发油的优化条件为:料液比1∶14(g/m L),提取温度50℃,提取时间40 min,提取率为2.776%,与预测值的相对误差为0.68%。 相似文献
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响应面优化白芨水溶性多糖提取工艺的研究 总被引:1,自引:0,他引:1
《山东化工》2019,(22)
目的 :确定白芨水溶性多糖提取的最佳工艺。方法 :采用水提法提取白芨多糖,通过Sevage法除去其中蛋白质,苯酚-硫酸法测定多糖含量,在单因素试验基础上,以多糖提取率为试验指标,响应面优化白芨多糖的最佳提取工艺。结果:响应面法优化得出最佳提取工艺为,提取温度79℃,提取时间4.10 h,液料比104∶1 mL·g~(-1),在此条件下试验所得的多糖提取率为(4.27±0.05)%。结论:说明此法合理可行,可用于白芨水溶性多糖的提取。 相似文献
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采用超声辅助双水相法提取普洱茶叶中的儿茶素,利用响应面法优化提取儿茶素的工艺条件。分别考察了料液比、丙醇体积分数、硫酸铵质量浓度、超声时间、超声温度对茶叶中儿茶素提取率的影响;在单因素研究的基础上,以5个因素为自变量,以儿茶素提取率为响应值,采用Box-Benhnken法设计5因素3水平响应面试验。结果表明,响应面模型与实际情况拟合良好,能较好地预测儿茶素提取率。最佳提取工艺:料液比1∶37、丙醇体积分数65%、硫酸铵质量浓度0.15 g/m L、超声时间25 min、超声温度35℃,得到儿茶素的提取率为46.01%(n=5),与预测值46.08%(n=5)接近,说明该提取工艺条件是合理可行的。与单因素试验确定的最佳提取率42.46%(n=5)进行比较,响应面法优化结果使儿茶素提取率提高了3.55%。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
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Conclusions It is significant that the purification on a single passage of viscose through porous ceramic corresponds to the result of a two-stage filtration of it in industrial filter-presses with standard fillings.Kiev Combine. Kiev Technological Institute of Light Industry. Translated from Khimicheskie Volokna, No. 3, pp. 20–22, May–June, 1969. 相似文献
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利用组件技术开发化工原理实验课件,给出了系统层、组件库层和应用层的架构划分。重点讨论了组件库的设计,给出了流体阻力这一典型实验的实现描述。实践证实,基于组件技术可以提高仿真实验的开发效率。 相似文献