菟丝子总黄酮提取工艺的研究

优选水浴振荡提取方法,以菟丝子总黄酮质量分数为考察指标,研究提取溶剂浓度、提取温度、固液比、提取时间、提取次数等因素对总黄酮质量分数的影响.通过正交试验,确定菟丝子总黄酮提取的最佳工艺条件为:提取温度60℃,固液比1∶14,乙醇体积分数55%,提取时间2h,提取次数2次.     

微波萃取法提取豆渣中大豆异黄酮工艺研究

为优化豆渣中大豆异黄酮的提取工艺,以乙醇为溶剂,采用微波辅助萃取法,选取乙醇浓度、提取温度、微波萃取时间、固液比作为考察条件,结果表明,豆渣中大豆异黄酮的最佳提取工艺为:乙醇体积分数80%,提取温度60℃,微波萃取时间40 min,固液比1∶10～1∶12之间。     

微波-超声波协同辅助夏枯草中熊果酸的提取工艺研究

文章采用微波-超声波协同辅助夏枯草中熊果酸的提取,对乙醇浓度、液固比、提取温度和提取时间进行了研究。结果表明,熊果酸提取的最佳工艺条件是:乙醇的体积分数为95%、液固比为12∶1、提取温度为70℃、提取时间为240 s,此条件下的提取率为98.84%。     

大枣总黄酮的提取及百分含量测定

探讨大枣总黄酮的最佳提取工艺条件.选定乙醇体积分数、料液比、提取时间及提取温度4个因素,进行单因素考察和正交试验,再根据芦丁标准曲线,测定大枣中总黄酮百分含量,研究4个因素对总黄酮的影响,最终确定最佳工艺条件.大枣总黄酮的最佳提取工艺条件为乙醇体积分数70%、料液比1∶10、提取时间3 h、提取温度80℃,在此条件下,大枣总黄酮百分含量为0.875 5%.回流提取法提取总黄酮简便、快速、节省溶剂,且有较高的得率.     

百合总皂甙的提取工艺

以百合中总皂甙含量为考察指标,应用正交设计对百合总皂甙提取工艺中的温度、乙醇体积分数、固液比、回流时间和提取次数进行了研究;以薯蓣皂甙为标准,香草醛-高氯酸为显色剂,冰醋酸为溶剂,用紫外可见分光光度计在波长为540 nm处对百合总皂甙的含量进行了测定.得出百合总皂甙的最佳提取工艺条件是:温度为70 ℃,乙醇体积分数为80%,固液比为1:6,提取时间为3 h,提取次数为3次;百合中总皂甙的含量为3.48 mg/g.     

莲心中总黄酮的提取工艺优化研究

以莲心为原料,以总黄酮得率和提取物得率为指标,考察提取温度、乙醇体积分数、提取时间和料液比4个主要因素,通过单因素和正交试验,研究莲心中总黄酮的最佳提取工艺。研究结果表明,莲心中总黄酮的最佳提取工艺为:乙醇体积分数70%,提取温度90℃,料液比1∶30,提取时间2.5h;在此工艺条件下,总黄酮得率1.669%,提取物得率30.748%。     

超声波辅助提取魁蒿总黄酮响应面法优化工艺

以魁蒿为原料,采用超声波法辅助提取总黄酮,考察料液比、提取时间、提取温度、乙醇体积分数和超声功率等因素对魁蒿总黄酮提取率的影响.在单因素实验的基础上,选取影响较大4个因素作为考察因素,以总黄酮提取率为响应值,应用响应面法优化魁蒿总黄酮的提取工艺.结果表明,在乙醇体积分数为70%、料液比为1∶20、提取时间为50 min、提取温度为65 ℃和超声功率200 W的最佳工艺条件下,魁蒿总黄酮的提取率为2.493%.     

苦丁茶中熊果酸的提取工艺

在苦丁茶中提取熊果酸的过程中,采用正交实验研究了乙醇体积分数、液固比、提取时间、提取温度、提取次数等对熊果酸浸出率的影响.正交实验的方差分析结果表明:对于熊果酸的浸出率,提取时间的影响最大,乙醇浓度和固液比的影响次之;最佳回流提取工艺条件为:在85℃水浴中,以90%(体积分数)乙醇水溶液为提取液,液固比为14 : 1,提取2次,每次提取2.5 h时,熊果酸的浸出率可达到1.44%.     

葛根中醇溶性总黄酮的提取工艺优化

采用正交试验法,优化醇法提取葛根中黄酮物质的工艺.以葛根素为对照品,采用分光光度法进行测定,以黄酮提取率为考察指标,对影响黄酮提取工艺的因素进行研究.首先,通过单因素试验研究提取温度、提取时间、乙醇浓度和液固比对黄酮提取率的影响,然后,利用正交试验法优化最佳提取工艺条件.结果表明,乙醇浓度对葛根素提取率影响最大,其次分别为提取温度、液固比、提取时间,最佳提取工艺条件为:提取温度80℃、提取时间60 min、乙醇浓度50%和液固比30:1(m L/g),在此条件下,黄酮平均提取率可达91.93%.采用乙醇浸提葛根黄酮是一种经济、快捷、高效的提取方法,具有很好的应用前景.     

响应面法优化蓝花荆芥中总黄酮提取工艺

采用乙醇热浸提法,考察料液比、乙醇浓度、提取温度以及提取时间对藏药蓝花荆芥全草中总黄酮提取率的影响,并结合响应面设计方法,对藏药蓝花荆芥全草中总黄酮提取工艺进行优化。由实验得到蓝花荆芥总黄酮最佳提取工艺为:乙醇体积分数35%,提取温度65℃,提取时间70min,该条件下总黄酮提取率为0.351%。     

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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