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%。     

超声波辅助提取石榴皮中熊果酸工艺研究

以石榴皮为原料,以熊果酸得率为指标,采用超声波辅助提取了石榴皮中熊果酸。分别研究了提取剂乙醇浓度、料液比、超声时间、超声温度对熊果酸提取的影响,通过正交试验优化了提取工艺。结果表明,熊果酸提取的最佳工艺条件是:乙醇体积分数50%、固液比1∶20、超声时间30 min、超声温度60℃,在最佳条件下,熊果酸得率可达1.1142%。     

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%。     

超声波法提取荞麦粉中黄酮类化合物的工艺研究

为获得最佳的荞麦粉黄酮超声提取工艺,在考察单因素的基础上,采用四因素三水平的正交试验,获得最佳的超声提取黄酮工艺条件为:乙醇浓度65%,料液比为1∶45,超声温度60℃,超声时间25 min。在最优工艺条件黄酮得率最高,为20.5 mg/g。     

云南竹灵芝中的总黄酮的提取研究

本实验主要研究了超声波辅助提取云南竹灵芝中总黄酮的提取工艺,先通过单因素实验确定料液比、超声时间、乙醇浓度、超声温度对灵芝中总黄酮提取效果的影响,再利用正交实验法优化得出最佳提取工艺条件。根据正交实验的结果,各因素对灵芝中总黄酮的提取影响由大到小依次为料液比乙醇浓度超声温度超声时间,最佳提取工艺为料液比1∶50,超声时间60 min,乙醇浓度70%,超声温度50℃。此时竹灵芝中总黄酮的得率可达7.269 mg/g。     

超声波-微波协同萃取金银花与绿原酸的工艺研究

本文研究了超声-微波协同萃取金银花黄酮与绿原酸的最佳工艺条件,以金银花黄酮与绿原酸得率为考察指标,研究了料液比、微波功率、乙醇浓度以及提取时间等因素对金银花黄酮与绿原酸得率的影响,在单因素的基础上通过正交试验对其提取工艺条件进行了优化。结果表明:最优提取工艺条件为料液比1:20(w/v),微波功率300w,乙醇浓度60%和提取时间5min,此时金银花黄酮的得率为13.93%,绿原酸的得率为7.02%。     

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％.     

龙眼茶茶粕中茶皂素提取工艺的研究

以永泰龙眼茶茶粕为原料,考察乙醇浓度、浸提时间、料液比、浸提温度等因素对茶皂素提取的影响,并进一步考察了超声波辅助提取茶皂素的工艺条件。结果表明,茶皂素的最佳提取工艺条件为:浸提时间为2 h,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。超声波辅助提取茶皂素的最佳工艺条件为:超声频率为40 k Hz,超声功率为500 W,浸提时间为50 min,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。利用超声波辅助乙醇法提取茶皂素的得率为12.9%,茶皂素纯度为65.6%。     

苦荞黄酮超声提取工艺研究

对苦荞粉中黄酮类化合物的超声提取工艺进行了研究。采取L9(34)正交实验,探讨了乙醇浓度、提取温度、料液比和超声时间对苦荞粉黄酮提取效果的影响。结果表明,乙醇浓度对提取效果的影响最为显著,最佳提取工艺条件为:乙醇浓度80%,提取温度60℃,超声时间30 min,料液比1∶30。     

龙眼茶茶粕中茶皂素提取工艺的研究

以永泰龙眼茶茶粕为原料,考察乙醇浓度、浸提时间、料液比、浸提温度等因素对茶皂素提取的影响,并进一步考察了超声波辅助提取茶皂素的工艺条件。结果表明,茶皂素的最佳提取工艺条件为:浸提时间为2 h,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。超声波辅助提取茶皂素的最佳工艺条件为:超声频率为40 k Hz,超声功率为500 W,浸提时间为50 min,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。利用超声波辅助乙醇法提取茶皂素的得率为12.9%,茶皂素纯度为65.6%。     

分解炉扩径的技术改造

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     

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。     

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。     

A study of miscibility of blends of polybutadienes of varying microstructure

The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure.     

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。     

粉煤灰中烧失量检测的不确定度分析

以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。     

生物油的成分分析及物性测定

以添加FeCl2的ZnCl2-KCl混合熔盐裂解纤维素和秸秆,制得生物油。采用傅立叶变换红外光谱法和气相色谱-质谱法分析生物油的成分。结果表明,生物油中成分复杂,含有氧元素、多种有机化合物,主要包括酮类、醛类、酚类及羧酸类等。测定了20～80℃生物油的密度和粘度,发现生物油的密度与温度呈较好线性关系,而生物油的粘度均大于水的粘度,且不同熔盐体系对秸秆生物油的粘度无较大影响。     

Effect of degree of deacetylation of chitosan on the kinetics of ultrasonic degradation of chitosan

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