蛹虫草菌丝体胞内多糖提取方法的研究

文中以提取温度、料液比、提取时间和提取次数为因素,采用正交试验研究热水浸提的最佳提取条件,并以此为基础研究热水浸提、冷热交替浸提、盐酸溶液浸提和氢氧化钠溶液浸提对蛹虫草菌丝体胞内多糖提取率的影响. 结果表明:热水浸提的最佳提取工艺为:m(料): V(液) = 1: 40,提取温度75 ℃,提取时间2.5 h,提取2次,多糖的提取率为14.74%,其中料液比为影响多糖提取率主要的因素,其他因素依次是提取温度、提取时间和提取次数. 按照此工艺,热冷交替浸提(热水浸提2.5 h + 冷水浸提48 h)多糖提取率最高,为15.92%. 55 g.L-1的氢氧化钠溶液浸提多糖的提取率为6.31%;25 gL-1的盐酸溶液浸提多糖的提取率为9.93%. 因此,冷热交替浸提对蛹虫草菌丝体胞内多糖提取率最高,其次是热水浸提、盐酸溶液浸提和氢氧化钠溶液浸提.     

超声波辅助提取桦褐孔菌多糖的工艺研究

研究通过超声波振荡处理对桦褐孔菌多糖的提取工艺的优化。超声波振荡处理后,采用水提醇沉法提取桦褐孔菌粗多糖,并利用苯酚-硫酸显色法,以葡萄糖为标准液,测定桦褐孔菌粗多糖中多糖的提取率。通过单因素分析法考察超声时间、水提温度、料液比对桦褐孔菌多糖提取率的影响,以及应用正交实验法来获得超声辅助提取桦褐孔菌多糖的最佳工艺参数。桦褐孔菌多糖超声提取的最佳工艺条件为超声时间20 min,料液比1∶50,提取温度60℃。在最佳工艺条件下实验所得多糖的提取率为5.03%。与传统的水浴浸提法相比,超声波辅助提取法不仅能缩短提取时间,而且提高了桦褐孔菌多糖的提取率。     

水浸法提取刺梨中多糖

为了简化刺梨多糖的提取工艺,达到节能、省时、方便的目的,用水提法提取刺梨多糖,探讨乙醇质量分数、提取温度、加热时间和料液比对多糖提取率的影响.采用正交实验优化工艺,以多糖提取率为评价指标,用蒽酮硫酸法测定多糖含量.水提法的最佳工艺条件为温度75 ℃,时间1 h,料液比1∶40,乙醇质量分数0%.在此条件下刺梨多糖的得率为4.7%.     

气-质联用法研究水溶性茯苓多糖提取方法

为研究水溶性茯苓多糖提取方法,分别采用热水提取法及超声提取法提取水溶性茯苓多糖,并以杂多糖的得率为指标设计正交试验,采用BSTFA(双(三甲基硅烷基)三氟乙酰胺)和DM F(N,N-二甲基甲酰胺)对杂多糖进行衍生化,采用D-果糖作内标进行气相色谱-质谱联用(GC-M S)定量分析.实验表明:热水浸提的最佳条件为固液比1∶40,提取时间3 h,提取温度90℃;超声波法最佳条件为固液比1∶40,提取时间60 m in,超声功率为100 W.热水提取和超声提取水溶性茯苓多糖的平均提取率分别为13.0%,8.6%,热水浸提法的多糖得率较高.均高于现有文献值报道.     

超声波协同酶法提取浒苔多糖工艺的研究

以浒苔为原料,采用超声波协同酶法提取多糖.在单因素试验的基础上采用正交试验优化浒苔多糖提取的工艺条件,并与热水浸提法进行比较.结果表明,浒苔多糖提取的最佳条件:超声时间20 min,料液比1∶50,温度50℃,酶用量3.0%,在此条件下重复试验,测得浒苔多糖的平均提取率为16.83%,同热水浸提法相比,多糖提取率明显提高,且提取时间大大缩短.     

黄花倒水莲多糖提取的最佳脱脂工艺

目的:优选黄花倒水莲多糖提取的最佳脱脂工艺条件.方法:用均匀设计方法设计最佳脱脂工艺条件,以提取物中多糖含量为测定指标,考察溶剂、回流时间及料液比三个因素对有效成分多糖提取的影响.结果:最佳脱脂工艺条件为乙醇和乙醚比例为1∶6.1(mL/mL),回流时间3h,料液比1∶20(g/mL),黄花倒水莲茎部多糖的提取率为2.65%.结论:优选的提取工艺提取率高,是一种省时、高效、节能的提取工艺.     

弱碱性介质下微波法提取灵芝多糖的优化

为了探寻一种高效的灵芝多糖提取方法,采用单因子分析和正交实验,对弱碱性介质下微波法提取灵芝多糖进行了优化研究.各因素对灵芝多糖提取的影响依次为提取时间,pH值,固液质量比,预浸时间.最适条件为预浸1.5 h,提取15 min,固液质量比1∶110,pH 8.0,提取2次.灵芝多糖提取率为3.200%,结果表明:该方法能显著提高灵芝多糖的提取率.     

真空耦合超声波提取绿豆衣中多糖工艺

以绿豆衣为试验原料,研究真空耦合超声波法提取绿豆衣中多糖的最佳工艺。通过单因素试验,研究提取时间、提取温度、超声功率、料液比、真空度对绿豆衣中多糖提取率的影响。正交试验结果表明,绿豆衣中多糖提取的最佳工艺为:提取时间50 min,提取温度70℃,料液比1:10,真空度0. 07MPa,超声功率100 W,在此条件下,多糖提取率为4. 88%。采用真空耦合超声波法能够提高效率,缩短时间,为绿豆衣中活性物质的提取提供依据。     

超声辅助提取血柚皮多糖工艺优化及其对自由基的清除作用

以漳州血柚皮为原料,采用超声波辅助热浸提法对血柚皮多糖进行提取,并以苯酚—硫酸法测定多糖提取率.分别对超声功率、超声温度、料液比、超声时间进行单因素和正交试验,并通过极差、方差分析对提取过程显著影响提取率的因素进行统计分析.结果表明,超声波辅助热浸提取血柚皮中多糖的最佳工艺条件为:超声功率80 W、超声温度65℃、料液比1∶30、超声时间70 min.该工艺条件下血柚皮多糖的提取率为18.51%,该方法的提取率比无超声波辅助的热浸提法提高了2.24%.以抗坏血酸为对照,考察了其羟自由基清除能力、DPPH自由基清除能力以及超氧阴离子自由基清除能力,结果显示,多糖对自由基的清除能力很强,但其对各自由基的清除能力均小于抗坏血酸.表明血柚皮多糖作为天然的抗氧化剂有一定的应用前景.     

超声辅助提取血柚皮多糖工艺优化及其对自由基的清除作用

以漳州血柚皮为原料,采用超声波辅助热浸提法对血柚皮多糖进行提取,并以苯酚—硫酸法测定多糖提取率.分别对超声功率、超声温度、料液比、超声时间进行单因素和正交试验,并通过极差、方差分析对提取过程显著影响提取率的因素进行统计分析.结果表明,超声波辅助热浸提取血柚皮中多糖的最佳工艺条件为:超声功率80 W、超声温度65℃、料液比1∶30、超声时间70 min.该工艺条件下血柚皮多糖的提取率为18.51%,该方法的提取率比无超声波辅助的热浸提法提高了2.24%.以抗坏血酸为对照,考察了其羟自由基清除能力、DPPH自由基清除能力以及超氧阴离子自由基清除能力,结果显示,多糖对自由基的清除能力很强,但其对各自由基的清除能力均小于抗坏血酸.表明血柚皮多糖作为天然的抗氧化剂有一定的应用前景.     

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