微波辅助提取贡菊中黄酮类化合物的工艺研究

以黄酮类化合物的提取含量为评价指标,采用微波辅助提取法,通过正交试验研究微波辐射时间、微波功率、乙醇浓度及其料液比等因素对提取率的影响.结果表明:提取黄酮类化合物最佳工艺条件为:70%乙醇做溶剂,辐射功率480 W,料液比1 g: 75 mL,辐射时间20 s/次×6次.该工艺简单、提取时间短、提取率高.     

微波辅助提取资木瓜多酚化合物工艺优化

采用单因素实验和正交法,考察了微波处理功率、微波处理时间、提取溶剂乙醇浓度和料液比等对资木瓜多酚含量的影响,确定了资木瓜多酚的最佳微波提取工艺.结果表明4种影响资木瓜多酚含量的因素依次为:乙醇浓度>微波功率>料液比>微波时间,乙醇浓度对资木瓜多酚提取影响较为明显.最佳提取工艺为:微波功率700 W,微波时间90s,乙醇浓度40%,料液比为1∶25(g/m L).提取物资木瓜多酚的含量为47.27 mg/g.     

微波辅助提取百香果中绿原酸的工艺研究

采用微波辅助提取与高效液相色谱技术,探索百香果中绿原酸的提取工艺.采用L9(34)正交实验法,考察了微波功率、微波提取时间、乙醇溶剂浓度以及料液比等因素对绿原酸提取得率的影响.研究得出微波辅助提取百香果中绿原酸的最佳工艺条件是:微波功率为中高火,微波时间2 min,乙醇溶剂体积分数80%,料液比1∶10,在这些条件下百香果中绿源酸提取得率为0.053%.     

微波法提取丁香色素

研究微波法提取丁香中食用色素的最佳工艺条件。方法：称取一定量的备用原料,选取微波功率、辐射时间、提取剂浓度、原料用量（g）与提取剂用量（mL）的配比（料液比）等进行单因素试验与正交试验。结果：微波功率是影响提取丁香色素的主要因素;影响丁香色素提取的顺序是微波功率〉料液比〉辐射时间〉提取剂浓度;最优工艺条件是微波辐射功率为500 W,辐射时间为120 s,提取剂为20%乙醇溶液,料液比为1 g：8 mL;提取液浓度与料液比之间存在交互作用。结论：正交试验是省时省力、结果易得的实用方法。     

微波辅助法提取鸡腿菇多糖工艺研究

本研究以鸡腿菇为原料,采用微波辅助法提取多糖,初步考察了料液比、微波功率、微波辐射时间对鸡腿菇多糖提取率的影响。结果最佳提取工艺条件为：料液比1:30、微波功率420W、微波辐射时间60s,在此工艺条件下提取率达到8.35%     

微波辅助提取马铃薯粉渣中果胶工艺研究

以马铃薯粉渣为原料,研究微波辅助提取果胶工艺.对比了液料比、提取pH值、微波加热时间、微波功率和硫酸铝用量对果胶提取率的影响,确定优化提取方案.结果表明,优化的提取条件为:液料比15∶1,提取pH值为2,微波加热时间为5 min,微波功率0.4 kW,硫酸铝用量7 mL,果胶提取率为1.853 7%,比传统提取方法时间缩短、产率提高、大量节约溶剂.     

密闭微波辅助萃取大黄蒽醌类有效成分的研究

利用具有压力控制附件的密闭微波萃取装置,提取大黄中的蒽醌类化合物.通过正交试验,考察了微波提取条件(包括溶剂、提取压力、微波辐射时间和料液比)对萃取率的影响.结果表明:溶剂为70%乙醇,提取压力为300 kPa,微波辐射时间为2 min,料液比为1∶30(mg/mL)时提取效果最佳.与索氏提取法及超声波萃取法相比,该方法具有萃取速度快、提取率高及溶剂用量少等特点.     

微波法提取淫羊藿中淫羊藿苷工艺研究

采用微波辅助提取淫羊藿中淫羊藿苷,以淫羊藿苷为考察目标,系统考察了提取溶剂、微波功率、提取时间、料液比四个因素对提取效果的影响.采用正交实验对提取工艺进行初步研究,确定最佳工艺条件为70%乙醇,微波功率400W,提取时间40分钟,料液比1:40.     

微波法提取柚皮中黄酮类化合物的工艺研究

应用微波萃取技术,以柚子皮为原料提取黄酮类化合物,用紫外分光光度法测定提取液中的黄酮类化合物的含量.在微波单因素浸提的基础上,采取正交优化试验,以探讨微波功率、料液比、微波处理时间、pH值、溶剂及溶剂的浓度对黄酮类化合物提取率的影响.正交实验表明,微波法提取黄酮类化合物的最佳条件是:微波功率是595W、微波处理时间20s、液料比为15:1、pH值为11、溶剂是浓度为80%的乙醇,在此条件下浸提,所得的黄酮类化合物含量为0.748%.在该工艺条件下,黄酮类化合物的得率比较高、所需要的时间短,是一种快速、高效、节能、环保的新型提取工艺.     

高效液相色谱法微波辅助提取废次烟叶中烟碱的工艺研究

以废次烟叶为原料,通过微波辅助处理废次烟叶,用高效液相色谱法检测提取液中烟碱的含量;考察了乙醇浓度、料液比、微波功率、微波辐射时间和微波提取温度对烟碱提取率的影响,得到了提取烟碱的最优工艺条件;实验结果表明,微波辅助提取烟碱的最佳条件为:乙醇浓度为60%,料液比为1∶45,微波功率为320 W,微波辐射时间为6 min,微波提取温度50℃,在优化条件下,烟碱提取率为89.2%;方法具有具有快速准确、灵敏度高、节约能源、绿色环保、适应范围广等特点。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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