超声波辅助提取莴笋叶中黄酮类物质工艺的研究

在单因素试验基础上,采用正交试验法,对超声波辅助提取莴笋叶中黄酮类物质的工艺进行了优化.确定其最佳提取工艺为:90%乙醇作为浸提剂,超声功率500 W,超声时间50 min,液料比4 mL/g.在此条件下,黄酮类物质的提取率为0.35%.     

超声波辅助法提取紫苏叶总黄酮的研究

采用超声波辅助法来提取紫苏叶总黄酮,通过研究提取剂乙醇浓度、料液比、超声波处理时间、浸提水浴温度等单因素及正交试验对紫苏叶总黄酮提取率的影响,确定了超声波辅助提取紫苏叶中总黄酮的工艺条件.结果表明,在浸提液为30%的乙醇、料液比1∶40、超声波（80 Hz、200 W）处理70 min、80 ℃水浴温度下提取2次,得到的紫苏叶粗提液总黄酮含量最高,提取率为21.81 mg/g.     

超声波辅助提取大豆异黄酮生产工艺条件优化

探讨用超声波法提取大豆中异黄酮的工艺,大豆粉过40目筛,以石油醚脱脂后通过单因素实验和正交试验改变不同的提取工艺选取最佳提取条件。结果表明超声波辅助提取大豆异黄酮是行之有效的方法,影响提取的主次因素为乙醇浓度>料液比>温度>时间。最佳提取条件为:提取时间40 min,料液比1∶30(g.mL-1),乙醇体积分数60%,温度70℃。     

超声波辅助提取柑橘皮色素的工艺研究

以柑橘皮为原料,运用超声波辅助提取法,通过单因素实验和正交试验确定柑橘皮色素提取工艺的最佳参数.在以三氯甲烷为提取剂时,单因素实验和正交试验柑橘皮色素的最佳提取条件分别为:料液比(柑橘皮粉质量比三氯甲烷体积)1∶20(g/mL)和1∶15(g/mL),浸提时间1 min和1.5 min,浸提温度30℃,各因素对柑橘皮色素提取效果的影响由大到小依次为:料液比>浸提时间>浸提温度.该工艺与传统浸提法相比具有提取速度快、色素提取效率高、不影响色素性质,处理简单等优点.     

超声波辅助提取花生壳中黄酮的工艺研究

采用超声波辅助法对花生壳中黄酮进行提取,研究了料液比、提取功率、提取温度及提取时间对花生壳中黄酮提取率的影响.通过单因素实验和正交试验确定了花生壳黄酮的优化提取工艺:料液比为1∶30,提取功率为100 W,35℃下浸提40 min,在此工艺下提取的花生壳中黄酮的质量分数为3.458%.     

基于超声波辅助法的杜仲籽蛋白提取工艺优化

采用单因素和正交试验方法对超声波辅助提取杜仲籽蛋白工艺进行了优化.先选取料液比、超声时间、超声温度、浸提pH值等条件对杜仲籽蛋白的提取工艺进行单因素实验,采用L9(34)正交试验确定本工艺最佳条件.实验结果表明,在超声波辅助提取杜仲籽蛋白最佳工艺条件（料液比为1∶25,超声时间为30 min,超声温度为50 ℃,浸提pH值为10.0）下,杜仲籽蛋白提取率为77.03%.     

超声辅助提取油莎豆可溶性糖

通过超声波处理,采用单因素试验和正交试验,考察了超声功率、超声时间、料液比、浸提温度对油莎豆可溶性糖提取的影响,并根据单因素试验结果对油莎豆可溶性糖提取工艺进行了四因素三水平的正交优化.结果表明:四个因素对油莎豆可溶性糖提取的影响主次顺序为浸提温度料液比超声时间超声功率;最佳工艺条件为超声功率700 W,超声时间10min,料液比(g/mL)1∶50,浸提温度80℃.在此工艺条件下可溶性糖提取率为14.7%.     

微波辅助热水浸提桔梗多糖工艺研究

以桔梗多糖为研究对象,采用单因素及正交实验对微波辅助热水浸提桔梗多糖工艺进行了研究,分析了料液比、温度、提取时间、微波功率、粒度、微波时间等因素对多糖提取率的影响.实验结果表明传统热水提取法的最佳工艺条件:浸提温度80℃,提取时间240 min,粒度80目,料液比1∶20;微波辅助热水浸提桔梗多糖的最佳工艺条件:料液比1∶20,微波处理时间2 min,微波功率400 W,热水浸提温度80℃,粒度80目,热水浸提时间240 min.采取短时高频微波前处理利于多糖析出,再通过后续热水浸提,其多糖提取率为32.85%,高于传统热水浸提(16.59%)和微波提取(22.83%).     

响应面法优化莲子低聚糖超声波辅助提取工艺

采用响应面分析法对超声辅助提取莲子低聚糖工艺参数进行优化.研究了超声波功率(300～500 W)、料液比(g/mL)1∶15～1∶25和提取时间(30～50 min)对超声辅助提取莲子低聚糖得率的影响,对实验数据进行回归分析,优化工艺参数.结果表明:超声辅助提取各试验因素对莲子低聚糖得率的影响次序为料液比超声波功率提取时间.优化所得莲子低聚糖超声波辅助提取较佳工艺参数为:超声波功率320 W,液料比1∶25,提取时间48 min,在该条件下,低聚糖得率为1.13%.与热回流提取法和微波辅助提取法相比,超声辅助提取法使莲子低聚糖得率分别提高66.18%和29.88%.     

响应面法优化野生五叶草莓总黄酮提取工艺

采用超声波辅助乙醇浸提法探索甘肃陇南产野生五叶草莓中总黄酮的最佳提取工艺条件。在单因素试验基础上,以料液比、超声时间、超声温度和乙醇体积分数为自变量,总黄酮提取率为因变量,利用Box-Behnken四因素三水平中心组合设计,对总黄酮提取工艺进行优化。结果表明,最佳提取工艺为:液料比12∶1(m L/g)、超声时间27 min、超声温度59℃和乙醇体积分数61%,野生五叶草莓总黄酮提取率实际可达10. 68 mg/g。超声波辅助乙醇浸提法的总黄酮得率为传统水浴回流法的2. 1倍,且该方法操作简单,重复性好。研究结果能为五叶草莓总黄酮的开发利用提供参考。     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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