花椒挥发油的超临界CO-2萃取工艺研究

介绍了超临界CO2萃取花椒挥发油的提取分离工艺,重点研究了原料粒度、前处理浸提时间、超临界CO2萃取温度、萃取压力、CO2体积对萃取率的影响. 应用正交实验优化出;影响超临界CO2萃取的主次因素为萃取温度＞CO2体积＞压力;最佳工艺参数为;原料粒度以60目(0.28mm)为宜,前处理浸提时间40min,萃取温度55℃,萃取CO2体积为30ml,萃取压力为34.475MPa,得到花椒挥发油的萃取率高达13.20%.     

花椒挥发油的超临界CO_2萃取工艺研究

介绍了超临界CO2萃取花椒挥发油的提取分离工艺,重点研究了原料粒度、前处理浸提时间、超临界CO2萃取温度、萃取压力、CO2体积对萃取率的影响.应用正交实验优化出:影响超临界CO2萃取的主次因素为萃取温度>CO2体积>压力;最佳工艺参数为:原料粒度以60目(0.28mm)为宜,前处理浸提时间40min,萃取温度55℃,萃取CO2体积为30ml,萃取压力为34.475MPa,得到花椒挥发油的萃取率高达13.20%.     

真姬菇子实体多糖提取的工艺研究

采用正交实验,分别对真姬菇子实体(鲜品)、(干品)多糖提取的工艺进行研究;取浸提时间(h)、乙醇总浓度(%)、温度(℃)、PH值、溶剂体积倍数(倍)五个因素,每个因素设4个水平.用正交表L45进行实验;得出真姬菇子实体(鲜品)多糖的最佳浸提工艺为:乙醇浓度80%、溶剂体积倍数为样品的15倍、温度为90℃、时间1小时、PH值5.真姬菇子实体(干品)多糖的最佳浸提工艺为:乙醇浓度80%、PH值7、时间1小时、溶剂体积倍数为样品的5倍、温度为90℃.真姬菇子实体(鲜品)粗多糖的纯化工艺:氯仿与正丁醇之比为1:0.3.复溶次数为2,样品与氯仿比为1:1.5.真姬菇子实体(干品)粗多糖纯化工艺:氯仿-正丁醇配比为1:0.1,复溶次数为1,样品-氯仿比为1:1.     

翅果油树多糖提取工艺的优化

本试验采用水提醇沉法提取翅果油树叶片中的多糖,探讨了浸提温度、浸提时间、固液比和浸提次数对多糖得率的影响.在单因素试验的基础上,通过正交试验确定最佳提取工艺条件.结果表明:在试验范围内,最佳提取温度为75 ℃,在此温度下提取次数对多糖提取率影响最大.翅果油树多糖提取的最优条件为提取温度75℃,固液比1∶ 10,浸提2次,每次浸提1.5 h,其水溶性多糖提取率达10.07%.     

用溶剂法提纯工业单宁酸工艺的研究

用溶剂法对倍子工业单宁酸进行了提纯研究，通过萃取温度，搅拌时间和粒度等条件的探索及对几种常用有机溶剂的对比和复配试验。结果所得工业单宁酸的纯度由７８％－８０％提高到９２．７６％，产品颜色变浅，质量稳定。     

微波辅助萃取红茶中咖啡碱的研究

研究了红茶中的有效成分咖啡碱在水中的溶出特性,以及茶叶粉碎度、料液质量比、浸提温度、浸提时间、提取液pH值、微波功率、微波作用时间等因素对咖啡碱溶出效果的影响,通过正交实验,对微波辅助萃取红茶中咖啡碱的工艺条件进行了研究.结果表明,茶叶不粉碎,料液质量比1∶30,浸提温度90℃,浸提时间30 min,提取液pH值为6,微波功率350 W,微波作用20 s,红茶中咖啡碱的浸出率可达3.90%以上.     

N,N二烷基取代酰胺萃取食用柠檬酸及其机理

本文以N,N二烷基取代酰胺为萃取剂,食品香料丁酸丁酯为稀释剂,直接从某柠檬酸厂发酵料液,以粉状活性炭并添加适量食盐,利用发酵温度适当加热预处理破乳后,在室温下五级逆流萃取,萃取率达96.6％,以60℃左右水七级错流反萃率达99％,所得产品的紫外,红外谱图与厂方用钙盐法生产之产品谱图基本一致。     

采用HBL101从锌置换渣高酸浸出液中萃取锗

针对现行的湿法炼锌渣中提取锗的研究现状,采用新型萃取剂HBL101从锌置换渣的高酸浸出液中直接萃取锗,考察了料液酸度、萃取剂体积分数、萃取温度、萃取时间和相比对萃取的影响以及氢氧化钠质量浓度、反萃温度、反萃时间和反萃相比对反萃的影响,并对萃取剂转型条件进行了研究.实验表明：有机相组成为30% HBL101+70%磺化煤油(体积分数)作为萃取剂,料液酸度为113.2 g·L-1 H2 SO4,其最佳萃取条件为萃取温度25℃,萃取时间20 min,相比O/A=1：4.经过五级逆流萃取,锗萃取率达到98.57%.负载有机相用150 g·L-1 NaOH溶液可选择性反萃锗得到高纯度锗酸钠溶液,其最佳反萃条件为反萃温度25℃,反萃时间25 min,相比O/A=4：1.经过五级逆流反萃,反萃率可达到98.1%.反萃锗后负载有机相再用200 g·L-1硫酸溶液反萃共萃的铜并转型,控制反萃温度25℃,反萃时间20 min,O/A=2：1.经过五级逆流反萃,铜反萃率可达到99.5%并完成转型,萃取剂返回使用.     

金花散茶饮料加工工艺研究

金花散茶是基于茯砖茶加工工艺开发的一种新型黑茶,其和传统茯砖茶相比具有金花菌含量高,口感与保健功效更佳的特点.以金花散茶作为原料,通过对比不同浸提条件下所制备茶饮料的色泽、香气和光密度,以探讨金花散茶饮料最佳提取工艺;另外研究了单宁酸、六偏磷酸钠和硅藻土三种试剂的使用对茶汤澄清度的影响;以及巴氏灭菌、微波灭菌与蒸汽灭菌方法对茶饮料储存稳定性的影响.研究结果表明,最佳浸提条件为浸提时间20 min,浸提茶水比1:80,浸提温度90℃;添加六偏磷酸钠澄清效果最佳;最佳灭菌方法为高压蒸汽灭菌法.     

食用菌多糖的提取工艺研究

本文以平菇子实体为对象,探讨了食用菌子实体多糖的提取工艺,考察了料水比、浸提时间、浸提温度、醇析浓度等因素对提取结果的影响.实验结果表明,水法提取的最佳工艺条件为1∶40料水比,100℃,提取3.0h,80%乙醇醇析;碱法提取的最佳工艺为0.7 mol/L氢氧化钠,1∶60料液比,100 ℃,提取5h,80%乙醇醇析.     

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.     

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