三氯乙烯和四氯乙烯处理方法研究进展

三氯乙烯和四氯乙烯的治理方法可归纳为物理法、生物法、化学氧化法、化学还原法。综述了最近有关文献报导的三氯乙烯和四氯乙烯的治理方法，总结了每种方法的优缺点及其发展动态。     

三氯乙烯和四氯乙烯在土壤和地下水中的污染及修复技术

 三氯乙烯和四氯乙烯在工农业生产中被广泛使用,由于其不合理的处置和相对持久性特征,使其成为地下水和土壤中分布最为广泛的污染物之一。因其具有挥发性、毒性和致癌性,受到了国内外的广泛关注。通过查阅国内外资料,本文较为系统地总结了三氯乙烯和四氯乙烯污染的来源、危害和污染现状,述评了修复三氯乙烯和四氯乙烯污染的物理方法、化学方法和生物方法,其中物理方法包括曝气法和活性炭吸附法等,化学方法包括化学氧化法和化学还原法等,生物方法包括微生物修复技术和植物修复技术。同时对三氯乙烯和四氯乙烯的污染修复技术的发展趋势进行了展望,认为微生物修复技术、纳米双金属颗粒技术和光催化氧化技术具有很好的应用前景,建议加强这三项技术的研究和应用。     

动态液相微萃取-气相色谱法测自来水中挥发性卤代烃

应用动态液相微萃取-气相色谱联用技术建立了自来水中挥发性卤代烃(四氯化碳、三氯乙烯、四氯乙烯)的快速分析方法.考察了萃取溶剂、溶剂体积、萃取次数、水样pH值和离子强度对液相微萃取的影响.该方法三氯乙烯、四氯乙烯的线性范围为10～50μg·L-1,四氯化碳的线性范围5.0～60μg·L-1,回收率80.2%～104.0%,相对标准偏差为2.6%～7.2%,检出限0.5～4.7μg·L-2.     

二元液体混合物粘度的研究

设计了测定液体混合物粘度的实验装置,用纯水对实验装置进行检验,其偏差与文献值相比小于5％。使用该装置对六种二元液体混合物的粘度,即丙酮和水,丙酮和甲醇、甲醇和三氯乙烯、甲醇和苯、四氯乙烯和苯、甲醇和四氯乙烯,从常温到高温加压测定。测定的六种液体混合物的粘度大体上随温度成反比例变化。     

OH与TCE和PCE形成的加成中间体的异构化反应机理研究

用从头计算法在ＵＨＦ／６－３１Ｇ水平下研究了羟基自由基与三氯乙烯和四氯乙烯形成的加成中间体的异构化反应。该反应形成了一个三元环状过渡态,活化势垒较低,分别为４７．１５ｋＪ．ｍｏｌ＾－１和２２．１９ＫＪ．ｍｏｌ＾－１。     

不同水体中挥发性卤代烃的对比

建立了吹扫捕集与气相色谱联用技术结合电子捕获检测器分析水体中多种挥发性卤代烃的方法.定量测定了淮安市自来水、古黄河水、运河、内运河及池塘水中的挥发性卤代烃并进行了对比.结果表明,自来水中主要含有氯仿、三氯乙烯、二溴一氯甲烷等,而自来水水源古黄河水中这三种卤代烃的含量极低.运河和内运河中四氯化碳的含量偏高,而且含有少量四氯乙烯.池塘水与古黄河水水质相近.     

二氧化硅-氧化锌溶胶凝胶法制备固相微萃取涂层的研究

采用溶胶-凝胶技术制备了二氧化硅-氧化锌-硅橡胶固相微萃取涂层,通过扫描电子显微镜观察了涂层的表面性貌。应用顶空固相微萃取-气相色谱联用技术分析了水中三氯乙烯和四氯乙烯,检出限分别为0.22 mg·L-1和0.30 mg·L-1,线性相关系数(R)分别为0.999 1和0.994 4,6次测定的相对标准偏差分别为4.21%和3.92%。     

旋转蒸发器法回收沥青及其改进方法研究

为研究旋转蒸发器法回收沥青胶结料的合理性,采用常规性能试验(针入度、软化点、延度、135℃布氏黏度试验)、SHRP流变试验(动态剪切流变仪(DSR)温度扫描试验、多应力重复蠕变(MSCR)试验)和傅里叶变换红外光谱(FTIR),从物理指标、流变行为和化学特性对比分析了原样沥青和回收沥青的技术性质,并探讨了旋转蒸发器法回收沥青的改进措施和判断回收沥青是否残留三氯乙烯或产生老化的新指标.结果表明:通过标准旋转蒸发器法回收的沥青仍残留部分三氯乙烯并产生了老化;利用常规指标偏差系数、三氯乙烯残留指数I_t、羰基指数I_c、亚砜基指数I_s、温度敏感性指标I_(GTS)和应力敏感性指标J_(nr-diff)能有效判别回收沥青是否残留三氯乙烯或者产生老化;采用改进旋转蒸发器法在4.6 kPa负压、130℃高温蒸馏2.0 h时回收的沥青技术性质与原样沥青基本一致,因此采用这种推荐的旋转蒸发器法回收沥青是合理的.     

Fe/C法去除地下水中TCE与PCE的影响因素研究

运用实验室批量试验,采用Fe/C微电解对地下水中的三氯乙烯(TCE)与四氯乙烯(PCE)污染物的去除进行了研究,确定了实验的主要影响因素为铁炭质量比及溶液pH值。实验的最优条件为采用质量比为1：1椰壳炭和50目铁粉,溶液pH=5,温度25℃。在最优条件下,Fe/C微电解对TCE与PCE混合废水的处理结果表明,Fe/C法对TCE的去除率为82.4FfFf,对PCE的去除率为59.4FfFf。     

Fe/C法去除地下水中三氯乙烯与四氯乙烯的影响因素研究

运用实验室批量试验,采用Fe/C微电解对地下水中的三氯乙烯(TCE)与四氯乙烯(PCE)污染物的去除进行了研究,确定了实验的主要影响因素为铁炭质量比及溶液pH值。实验的最优条件为采用质量比为1∶1椰壳炭和50目铁粉,溶液pH=5,温度25℃。在最优条件下,Fe/C微电解对TCE与PCE混合废水的处理结果表明,Fe/C法对TCE的去除率为82.4%,对PCE的去除率为59.4%。     

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.     

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     

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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