由五倍子制取鞣花酸

以五倍子为原料浸取单宁酸，由单宁酸氧化制备鞣花酸。选用Na2CO3作添加剂，降低单宁酸的浓度，增长反应时间，鞣花酸的产率可高达54％。采用红外光谱（IR）法和高效液相色谱法（HPLC）对制备的鞣花酸进行了分析。     

工业单宁酸制备方法的研究

将传统只用水浸提制取工业单宁酸的方法改为以混合溶剂和水分步提取的工艺方法．新方法提取时间缩短，产率提高，产品质量上升．对制备工艺和影响产品质量的因素进行了较为详尽的讨论．     

Fe(Ⅲ)强化单宁酸原位修复Cr(Ⅵ)污染含水层反应机理及效能

研究Fe(Ⅲ)对单宁酸(TA)原位修复含水层Cr(Ⅵ)污染的反应机理及效能. 结果表明，Fe(Ⅲ)通过与单宁酸配合可有效提高单宁酸对Cr(Ⅵ)污染含水层的修复效率. 单宁酸分子中邻苯三酚结构中两个相邻的酚羟基与Fe(Ⅲ)配合并提供电子，因此修复1 mol Cr(Ⅵ)至少需要9 mol单宁酸；若使Fe(Ⅲ)达到最好的强化效果， 则要求n（TA）∶n（Fe(Ⅲ)）=3∶5， 此时单宁酸-Fe(Ⅲ)结构最稳定， 储存容量最大. 在Cr(Ⅵ)污染被修复后， Fe(Ⅲ)在单宁酸的作用下形成稳定的FeOOH， 对Cr(Ⅲ)进行吸附并形成共沉淀， 从而达到去除总Cr的目的.      

流动注射化学发光法测定啤酒中的单宁酸

基于在甲醛存在条件下，酸性介质中，高锰酸钾氧化单宁酸产生较强的化学发光反应，结合流动注射技术，建立了单 宁酸的流动注射化学发光测定方法。该法的化学发光强度在单宁酸的浓度为8． 0×10~(-8) ～5． 0×10~(-6) mol/L 范围内呈良好的线 性关系，检出限为5． 0×10~(-8) mol／L(S/N=3) ，测定的相对标准偏差为2． 7％(N=11) 。该法用于测定几种啤酒中微量的单宁酸 测定，结果令人满意。     

单宁酸在疏水性微塑料/水界面上的吸附

为理解水环境中新污染物微塑料对溶解性天然有机质的吸附作用，以单宁酸为天然有机质的模型化合物，考察了聚丙烯(PP)、聚甲醛(POM)、聚苯乙烯(PS)、聚氯乙烯(PVC)和聚对苯二甲酸乙二醇酯(PET)5种疏水性微塑料对水相中单宁酸吸附的动力学和等温线.实验结果表明，吸附在8 d内达到表观平衡，吸附过程可以很好地用假二级吸附动力学模型描述，吸附等温线更符合朗格缪尔吸附等温模型(质量浓度范围为10～150 mg/L),单宁酸在微塑料/水界面的吸附为单分子层吸附.具有非极性表面的PP、PS和PVC对单宁酸吸附的朗格缪尔吸附亲和力常数(0.070～0.115 L/mg)大于具有弱极性表面的POM和PET(0.042～0.045 L/mg),这主要是由于不同微塑料表面疏水性的差异，而非不同微塑料与单宁酸之间相互作用的差异.     

基于DSR和RV的单宁酸改性沥青高温性能试验研究

探究了单宁酸改性沥青的复数剪切模量、相位角、车辙因子和黏度随着不同温度不同单宁酸改性沥青掺量的变化而变化的情况。分析了根据黏温曲线确定单宁酸改性沥青的拌和温度和碾压温度以及车辙因子与温度的对数关系。研究表明,当温度相同时,随着单宁酸掺量增加,复数模量、车辙因子逐渐提高,而相位角逐渐降低,沥青抵抗高温流变性能增强;相同温度下,黏度随单宁酸掺量增加而增加;碾压温度和拌和温度随单宁酸掺量而成倍增加,建议掺量不大于6%;从布氏黏度和动态黏度,单宁酸的掺入,降低了沥青的感温性,各单宁酸掺量下,车辙因子和温度具有良好双对数线性相关关系,回归系数先减小后增大,对单宁酸改性沥青还需要进一步探讨研究。     

五倍子单宁酸中没食子酸的去除及其含量测定

单宁酸是五倍子提取物中的主要成分,被广泛应用于医药、食品、日化等方面.但由常规方法制备的单宁酸中常含有没食子酸杂质,影响产品的品质和应用.为了提高五倍子单宁酸提取物的纯度,以单宁酸为原料、没食子酸含量为考察指标,采用简单易得的无机碱(碳酸氢钠)选择性去除没食子酸,对单宁酸的提纯工艺进行优化.对优化后的工艺进行放大实验,...     

单宁酸磷脂复合物的制备及其理化性质研究

以单宁酸和大豆卵磷脂为原料制备单宁酸磷脂复合物.以单宁酸与磷脂的复合率为评价标准,通过单因素实验考察反应温度、反应时间、反应物初始质量浓度和投料比例对复合率的影响,由正交试验得到最优条件.研究了单宁酸磷脂复合物的理化性质及溶解性能.结果表明,单宁酸磷脂复合物的最佳制备工艺为:以乙醇为反应溶剂,反应温度为60℃,反应时间为1.5 h,单宁酸质量浓度为4mg/m L,投料质量比例为2∶1.红外光谱和紫外光谱分析表明,单宁酸与磷脂未形成新的化合物而是通过分子间作用力形成的复合物.与单宁酸相比,复合物在水中溶解度有所降低,但在正辛醇中溶解性有明显改善.     

不同药液浸泡树棒培养蜜环菌材试验

本文对六种不同药液浸泡树棒培养密环菌菌材进行了研究，结果表明：0．5ppm三十烷醇加300ppm单宁酸的混合液浸泡树棒，培养蜜环菌，其接菌率高、菌生长势好，明显优于沿用已久的0．25％硝酸接溶液浸泡树棒培养密菌菌材的方法。     

聚乳酸/单宁酸复合材料的制备与性能研究

聚乳酸(poly lactic acid, PLA)是一类具有良好热加工和机械性能同时又可生物降解的绿色环保高分子材料,其在实际应用中存在耐热性差、质硬而脆等缺点。以聚乳酸和天然植物多酚单宁酸(tannic acid, TA)为原料利用共混改性的方法制备得到一系列不同单宁酸添加量的聚乳酸/单宁酸(PLA/TA)复合膜,利用X射线衍射仪、傅立叶红外变换光谱仪、热重分析仪、万能拉力试验机、紫外可见分光光度计对复合材料进行表征及性能测试。结果表明,在PLA/TA复合膜中,聚乳酸链段和单宁酸分子之间存在较强的氢键作用,单宁酸的加入明显提高了复合膜的耐热性能和机械性能。此外,由于所添加的单宁酸具备丰富的多酚结构,使复合膜具有较强的紫外屏蔽功能,在包装材料领域具有潜在的应用前景。     

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.     

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