陕西产绞股蓝总黄酮提取工艺研究

以陕西产绞股蓝为原料,采用乙醇回流法提取绞股蓝中总黄酮.考察了提取溶剂、温度、时间、次数和料液比对绞股蓝总黄酮得率的影响,并进行正交试验优化.结果表明:绞股蓝总黄酮最佳提取工艺为料液比1:30(g·mL-1),提取温度80℃,乙醇体积分数70％,回流提取2次,每次1 h,该条件下的绞股蓝总黄酮得率为7.91％.     

超声辅助优化小麦胚芽中总黄酮提取工艺

超声辅助提取小麦胚芽中黄酮类化合物,考察料液比、乙醇体积分数、提取时间、提取温度对小麦胚芽黄酮得率的影响。结果表明,各因素影响的主次顺序为:乙醇体积分数>料液比>提取温度>提取时间;提取最佳工艺为:料液比1∶30 g/mL,乙醇体积分数40%,提取时间60 min,提取温度50℃。在此最佳条件下,小麦胚芽总黄酮的得率为1.52%。     

超声辅助优化小麦胚芽中总黄酮提取工艺

超声辅助提取小麦胚芽中黄酮类化合物,考察料液比、乙醇体积分数、提取时间、提取温度对小麦胚芽黄酮得率的影响。结果表明,各因素影响的主次顺序为:乙醇体积分数料液比提取温度提取时间;提取最佳工艺为:料液比1∶30 g/mL,乙醇体积分数40%,提取时间60 min,提取温度50℃。在此最佳条件下,小麦胚芽总黄酮的得率为1.52%。     

麻竹叶总黄酮提取工艺的研究

研究从麻竹叶中提取竹叶总黄酮的工艺及其影响因素.结果表明,提取时间、提取温度、液固比和搅拌速率对得率的影响较为显著.在实验范围内的最佳工艺条件为:乙醇体积分数60%,温度80℃,液固比为25:1(mL:g),搅拌速率300 r/min,每次提取2 h,共提取两次,总黄酮得率为1.06%.     

黄芪中总黄酮的提取纯化工艺研究

目的优选黄芪中总黄酮的提取纯化工艺参数。方法以总黄酮得率为考察指标,采用单因素试验及正交试验考察乙醇体积分数、回流提取时间、提取温度及料液比对提取效果的影响;以总黄酮纯度为考察指标,考察D101大孔吸附树脂对黄酮提取物的纯化效果。结果最佳提取工艺为:采用体积分数为85%的乙醇水溶液,以1∶20(g∶mL)的料液比回流提取2.5h,提取温度为80℃,总黄酮得率可达2.385(mg·g~(-1));采用石油醚脱脂与D101大孔吸附树脂相结合的手段对总黄酮提取物进行纯化,产品纯度达30.63%。结论该提取纯化工艺操作简单、易行,适用于黄芪中总黄酮的大规模生产。     

草珊瑚总黄酮的超声提取工艺研究

研究了超声法提取草珊瑚总黄酮的工艺.影响草珊瑚总黄酮提取率的主要因素是乙醇体积分数,其次是提取次数,提取时间和液料比对提取率影响不显著.正交实验确定草珊瑚总黄酮的最佳超声提取条件是:40%乙醇,液料比10∶1,提取时间40 min,提取3次.此条件下总黄酮得率为8.53%.超声提取法具有短时高效的优点,适合于草珊瑚总黄酮的提取.     

响应曲面法优化野菊花中总黄酮的超声提取工艺

以总黄酮得率为评价指标,采用单因素实验和响应曲面法实验优化野菊花中总黄酮超声提取工艺。确定最佳提取工艺为:乙醇体积分数60%、超声提取时间40min、液料比15∶1(mL∶g)、超声提取温度50℃、超声功率1 080 W,在此条件下,总黄酮得率可达0.881%。该提取工艺设计合理,为进一步研究野菊花中总黄酮的应用提供了科学依据。     

响应面法优化固定超声辅助提取玫瑰花黄酮的工艺

以玫瑰花为原料,固定超声法辅助乙醇提取黄酮,并采用响应面法进行工艺优化.主要考查了乙醇体积分数、料液比、提取温度、提取时间对黄酮提取得率的影响,优选较佳提取工艺参数:乙醇体积分数60％,料液比0.5:13 g/mL,提取温度50℃,提取时间76 min,此条件下黄酮提取得率3.77％.     

山药活性成分的提取

对鲜山药中水溶性粗多糖的提取工艺进行了研究.通过单因素实验和L9(34)正交实验,研究了料液比、提取温度、提取时间和乙醇体积分数对粗多糖得率的影响.极差分析及方差分析结果表明,乙醇体积分数和提取温度是影响山药粗多糖提取的主要因素.最佳工艺条件为:料水比1 g∶15 mL,浸提温度100 ℃,浸提时间3 h,乙醇体积分数5%.在此工艺条件下,鲜山药多糖的得率为2.32%.     

微波辅助提取花生壳总黄酮的工艺优化

以花生壳为原料,采用微波辅助提取花生壳中的总黄酮。探讨了乙醇体积分数、微波时间、料液比和提取温度对总黄酮提取的影响。在单因素的基础上,通过正交试验优化工艺。结果表明,最佳提取工艺条件为:微波时间2min,提取温度50℃,乙醇体积分数70%,料液比1∶25(g/m L),在此工艺条件下,花生壳总黄酮的提取率为8.9436%。     

乙烯酮(双乙烯酮)下游产品废水的治理技术

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。     

Semi-empirical equation of state of metals. Equation of state of aluminum

A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO₂) of density 0.08 g/cm³. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

三种煤样燃烧热的测定

本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。     

Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone

A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.     

小议汽车涂装工艺设计对涂装成本的影响

论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。     

气化给煤系统故障分析

气化给煤装置自投运以来,出现了气化煤仓堵煤、称重给煤机输送皮带因跑偏而损伤以及清扫装置故障频繁等问题,多次造成气化系统减负荷运行。通过对出现的各种问题进行分析,找到了产生这些问题的原因,并有针对性地采用配煤和改进清扫链等措施,使出现的问题得到了极大的改善。     

Measurement of the gradient of viscosity with composition of mixtures of non-ideal gases

A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.     

醋酸纤维素取代基分布与性质的关系

分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。