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二十二碳六烯酸(DHA)和二十碳五烯酸(EPA)具有许多重要的生理活性和营养学功能。通过实验研究了提取温度、料液比、超声功率、频率以及提取时间对超声提取海藻DHA和EPA影响和超声提取的效果,结果表明,适当提高提取温度、溶剂量、超声功率或延长提取时间,DHA和EPA提取率随之提高。当超声功率为50W时,随着超声频率增加,DHA和EPA提取率反而降低。相同料液比时,55℃超声法提取1h比65℃溶剂法提取2h的DHA和EPA提取率提高25%~44%。不同料液比时,当料液比为1:4.5,超声法提取1h,DHA和EPA的提取率分别为79.48%、81.52%;而溶剂法料液比为1:5.5,提取2h时,DHA、EPA的提取率分别仅为63.57%、64.87%。超声提取不仅降低了提取温度、减少了提取时间和提取溶剂量,而且使DHA和EPA提取率明显提高。 相似文献
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采用超声波协同提取法对荷叶总黄酮进行提取,通过单因素试验确定最佳的荷叶总黄酮提取工艺:提取时间20min,料液比1:30,乙醇浓度60%,温度50℃,验证试验证明实际提取率为4.85%。 相似文献
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以甘肃平凉油用牡丹为籽原料,以单因素实验结果作为研究基础,对超声-微波协同提取时间、超声、微波的功率、温度、料液比等影响因素进行试验,应用中心组实验设计方案,以牡丹籽得油率为响应值,进行超声-微波协同萃取牡丹籽油,找出了影响提取牡丹籽油的交互因素:以石油醚为提取溶剂时,选择1∶6~1∶9范围内的料液比,用400~800 W的微波在30℃~50℃下辐照6~8 min,同时在480~560 W超声功率下振荡10~20 min,牡丹籽粗油得油率最高为34%,微波温度和功率、超声功率和振荡时间、超声功率和料液比以及振荡时间和料液比之间交互作用显著。 相似文献
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目的 采用响应面法优化罗汉松种子总黄酮超声提取工艺,并考查总黄酮的抗氧化活性。方法 基于单因素试验,以料液比、超声时间、超声温度为自变量,以总黄酮得率和DPPH自由基的清除率为因变量,采用三因素三水平的响应面分析法,确定最佳提取工艺条件。结果 得到最佳工艺参数:在超声频率为40 kHz、超声功率为200 W时,料液比(g/mL)为1∶50、超声温度为70℃、超声时间为2.7 h,其理论预测值总黄酮得率为27.54mg/g(n=3,相对标准偏差为1.63%)。当添加稀释10倍的总黄酮提取液0.50mL时,对DPPH自由基的清除率达到87.2%、对Ce(Ⅳ)还原率达到84.2%;当添加稀释10倍的总黄酮提取液0.90mL时,对OH自由基的清除率为88.1%。结论 采用响应面法优化得到的超声波辅助提取工艺稳定、可靠,可用于罗汉松种子总黄酮的提取。罗汉松种子总黄酮可作为优良的天然抗氧化剂资源。 相似文献
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为提高荸荠多糖的得率,采用超声波辅助法提取荸荠多糖。通过单因素试验研究超声波功率、料液比、提取温度、超声处理时间、乙醇浓度对荸荠多糖得率的影响,确定荸荠多糖的最佳提取工艺。单因素试验结果表明,在本试验条件下,超声波功率为300W、料液比1:10、提取温度为50℃、超声时间25min时荸荠多糖得率最高。 相似文献
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研究荷叶中总黄酮的提取工艺,从而提高荷叶的附加值。采用响应面法优化醇法提取法对荷叶总黄酮的工艺:料液比1:26.13,提取时间1.05h,提取温度76.89℃,乙醇浓度60.85%,验证试验证明实际提取率为3.82%。 相似文献
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以苦杏仁为原料,采用溶剂法提取杏仁油,通过对比几种溶剂的提取率,选择了正己烷为最佳提取溶剂,研究了料液比、浸提时间、浸提温度、浸提次数对杏仁油提取率的影响,得出杏仁油的最佳提取条件。 相似文献
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目的 研究采用超声波-微波协同法萃取沙棘籽油的工艺条件,及对沙棘籽油脂肪酸组成的影响。方法 选择溶剂种类、萃取时间、液料比、超声波功率、微波功率、萃取温度等6个因素进行单因素试验。在单因素试验的基础上,选择正己烷为萃取溶剂,以提取率为响应值,选择萃取时间、液料比、超声波功率、萃取温度等4个因素进行响应面优化试验。对此条件下得到的沙棘籽油和超临界CO2法萃取得到的沙棘籽油中的脂肪酸组成成分进行分析。结果 得到了超声波-微波协同法萃取沙棘籽油的最佳工艺条件,萃取时间为22 min,液料比值为9 mL/g,超声波功率为628 W,微波功率为200 W,萃取温度为57 ℃,在此条件下沙棘籽油的提取率可达13.97%。超声波-微波协同法萃取得到的沙棘籽油,其不饱和脂肪酸质量分数高达88.93%,最高的为亚油酸(39.60%),其次为亚麻酸(32.60%)。结论 超声波-微波协同萃取法是一种提取沙棘籽油的有效方法。 相似文献
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以蔗糖和蛭石为原料,在超声辅助条件下采用溶液插层法制备插层型蔗糖/蛭石纳米复合材料。X射线衍射(XRD)、红外光谱(FTIR)分析表明,蔗糖/蛭石复合物样品的d001值为1.852nm;样品的红外谱图中出现甲基和亚甲基特征峰2761cm-1和2969cm-1。将蔗糖/蛭石复合物在氮气氛下碳化后,样品的XRD(d001=1.247nm)和红外光谱结果(甲基和亚甲基特征峰2761cm-1和2969cm-1消失)表明,碳/蛭石复合材料层间夹有碳,进一步证实得到插层型蔗糖/蛭石复合材料。同时,确定了优化插层反应工艺条件,超声功率为400W,物料配比为蛭石:蔗糖=1:2.5,超声水化时间为0.5h,超声反应温度为70℃,反应时间为2.5h,静置时间2h。 相似文献
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This work elucidates the removal of copper from industrial sludge by traditional and microwave acid extraction. The effects of acid concentration, extraction time, sludge particle size and solid/liquid (S/L) ratio on copper removal efficiency were evaluated. Leaching with more concentrated acid yielded greater copper content from the industrial sludge. The experimental findings reveal that the most economical traditional extraction conditions were the use of 1N sulfuric or nitric acid for 60 min at an S/L ratio of 1/20; however, at an S/L ratio of 1/6, the extraction time needed to achieve the same copper removal efficiency was increased to 36 h. Increasing the microwave power and reducing the S/L ratio increased the copper extraction efficiency and the effect in the larger S/L ratio system was more significant. A comparison of the results of microwave-assisted (microwave only) and microwave-enhanced (microwave with addition of active carbon) acid extraction demonstrated that under both conditions, S/L ratio = 1/6 and 1/20; adding active carbon shortened the extraction time required to achieve 80% copper extraction efficiency from 20 to 10 min. These experimental results indicate that the most important factors that most strongly affected microwave acid extraction were the addition of a microwave absorber, the microwave power input and the S/L ratio. The sludge particle size did not significantly affect the copper extraction. The results reveal that sulfuric acid was an effective extractant and that the copper fraction in the extracted sludge shifted from being mostly bound to the Fe–Mn oxides and organic matter, to being mostly bound to organic matter and remaining as a residue during acid extraction. 相似文献
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合成条件对粉煤灰合成沸石过程中沸石生成和品质的影响 总被引:14,自引:0,他引:14
系统研究了由粉煤灰合成沸石过程中温度、反应时间、液固比和NaOH浓度等合成条件对沸石生成及其阳离子交换容量(CEC,CationExchangeCapacity)的影响.结果表明,温度主要影响沸石矿物的结晶度;液固比主要影响沸石种类;NaOH浓度和反应时间对两者均产生明显影响.合成产物的CEC随温度、液固比、反应时间呈快速增加,并在分别达到110℃、2.5和16h时趋于一最大值.NaOH浓度越高,合成产物CEC也越高,至2mol·L-1时达到最大,之后显著下降.考虑到合成成本,最佳合成条件初步归纳为:温度110-120℃,反应时间8-16h,液固比2.5,NaOH浓度2mol·L-1. 相似文献
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茭白苞叶中总黄酮提取及其体外抗氧化性能研究 总被引:2,自引:0,他引:2
运用超声波技术辅助提取茭白苞叶中的总黄酮,经正交实验得出茭白苞叶中总黄酮提取的最佳工艺参数:超声波功率700 W,温度60℃,料液比(g/mL)1∶60,乙醇质量分数浓度为60%,提取时间为35 min,茭白苞叶中总黄酮最大提取率为1.127%.采用抗坏血酸作为对照,全面测定了茭白苞叶总黄酮对超氧阴离子自由基、羟基自由基、DPPH自由基的清除率,以及还原能力、抗脂质过氧化活性和对食用油脂的抗氧化性的影响,结果表明,白苞叶中的总黄酮是一种有开发价值的天然抗氧化剂. 相似文献
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The formation of hollow granules from hydrophobic powders in a high-shear mixer granulator has been investigated by changing the binder/powder mass ratio and studying its effects on granule size and structure. In this study, a mixer granulator was filled with 100 g of hydrophobic fumed silica and then varying quantities of 5% Hydroxy Propyl Cellulose solution was slowly sprayed into granulator. A range of liquid to solid mass ratios between from 0.5:1 to 15:1 was used. Granules were then dried at 60 °C in a fan forced oven. This paper compares the particle size distributions, scanning electron microscopy (SEM) images and X-ray tomography (XRT) images of hollow granules as a function of the liquid to solid mass ratio. The granule mean size increased and the fraction of un-granulated (fine) particles decreased as the liquid to solid mass ratio increased. Simultaneously, the morphology and structure of the hollow granules changed from a spherical to a deformed structure which indicates the importance of choosing the optimal liquid to solid mass ratio. The optimal liquid to solid mass ratio for Aerosil R202 powder in this study was found to be between 3:1 and 6:1. The final granule shape and size distribution are dependent on the liquid to solid ratio if the liquid marble nucleation process starts with a preformed droplet template. 相似文献