18种硝基苯对大型蚤的毒性与结构相关性研究

目的：建立预测硝基芳烃化合物毒性数据的预测方程。方法：以大型蚤（Daphniamagna）为实验材料,求取18种硝基化合物的急性毒性数据48h－IC50,化观察了中毒症状。应用五种理化参数-EHOMO、ELUMO、ELUMO、logP、VX和QNO2对所得的毒性数据进行定量构效关系（QSAR）研究,得到预测方程。结果：得到硝基芳烃对大型蚤的QSAR表达式：－logIC50＝0．21＋0．664（-EHOMO）＋0．0302VXn＝18r＝0．8221,P＜0．001,应用上述方程对18种化合物进行了毒性预测,结果实测值和预测值拟合较好,残差较小。结论：可以利用上述得到的QSAR表达式对硝基芳烃毒性进行预测,推测化合物的环境行为。     

苯胺类二元混合物对发光菌和大型蚤联合毒性的比较研究

测定了苯胺与6种取代苯胺对发光菌和大型蚤的单一毒性及其毒性单位比为1∶4,1∶1,和4∶1的二元混合物的联合毒性.采用相加指数法对联合毒性进行了评价.结果表明,苯胺与取代苯胺的二元混合物在3种配比下对发光菌的联合毒性主要表现为相加作用,而对大型蚤的联合毒性则为协同作用.     

重金属铜和两种苯酚类化合物对大型蚤的联合毒性

以大型蚤(Daphnia magna)为试验生物,测定了铜、间氯苯酚和间硝基苯酚对大型蚤的单一毒性.有机物的毒性大小为:间氯苯酚(-lgV_(LC50)=4.43)间硝基苯酚(-lgV_(LC50)=3.60).在测定重金属单一毒性(-lgV_(LC50)=5.73)的基础上,分别测定了二元有机-无机复合体系(重金属铜以其单一毒性0.2倍、0.5倍和0.8倍的半数致死浓度分别与间氯苯酚和间硝基苯酚混合)对大型蚤的联合毒性,并采用毒性单位法(TU)和相加指数法(AI)对联合毒性进行了评价.结果表明:两种评价方法的评价结果一致,两种苯酚类化合物与铜组成的二元混合体系的联合毒性为相加作用和拮抗作用;当铜浓度一定时,铜-间氯苯酚混合物对大型蚤的拮抗作用强于铜-间硝基苯酚混合物的拮抗作用;当铜与两种苯酚类化合物以1∶1的毒性单位混合时拮抗作用最强(毒性单位法的M值分别为3.01和1.88),原因可能是此种混合体系中有机物和无机物产生了较多的络合物,减毒作用明显.     

硝基芳烃对隆线蚤的毒性作用及QSAR研究

得到２４种硝基芳烃对隆线蚤的半数有效抑制浓度值,其毒性由高到低的顺序为：二硝基氯苯〉二硝基苯〉二氯硝基苯〉硝基苯胺＝硝基氯苯＝硝基甲苯〉硝基苯酚〉硝基苯,其中１１种化合物对隆线蚤的－ｌｇＥＣ５０,以Ｉ,Ｘ－Ｅ１／２,∑σ,ΔＨｆ,－Ｅｌｕｍｏ,ｌｇｐ七种物理化学参数做ＱＳＡＲ计算,得出八种回归方程。     

取代芳烃与七种生物毒性的定量构效关系

根据成键原子的结构特征定义了一种原子点价公式,构建了取代芳烃的分子连接性指数．研究了取代芳烃对斜生栅列藻急性毒性,日本长腿蛙蝌蚪急性毒性、绿藻急性毒性、大型蚤毒性、斑马鱼毒性,隆线蚤毒性和金鱼毒性等七项生物活性分别同取代芳烃分子连接性指数的相关性．结果表明：分子连接性指数具有良好的结构选择性和性质相关性,可用于预测其它取代芳烃的生物活性．     

2,4-二硝基甲苯与硝基苯衍生物对发光菌的联合毒性

测定了2,4-二硝基甲苯(2,4-DNT)与5种硝基苯衍生物对发光菌的单一毒性和在等剂量下二元混合物的联合毒性.采用毒性单位(TU)、相加指数(AI)、相似性参数(λ)和混合毒性指数(MTI)进行联合毒性评价,结果表明,5种二元混合物的联合作用均为协同作用;比较了不同对位取代基对混合物协同作用强弱的影响,采用混合毒性指数的评价结果与其它3种方法略有不同,但在以2,4-DNT为底物的二元混合体系中,对硝基氯苯的协同作用最弱.     

基于QSAR和PCA方法的硝基芳烃综合毒性评价

化学品的风险评价与管理应该关注基于多种生物体效应的综合毒性。为了评价毒性数据稀缺化合物的综合毒性,以50种硝基芳烃为研究对象,收集了它们的多种生物毒性数据,建立了稳健的定量结构活性相关(quantitative structure-activity relationship,QSAR)模型,预测缺失毒性数据,解释了硝基芳烃的致毒机理——硝基芳烃与生物受体分子的亲电反应活性是决定其毒性的主要因素。然后应用主成分分析(principle componentan alysis,PCA)方法对基于QSAR模型计算获得的50种硝基芳烃的各种生物毒性数据进行分析,计算综合毒性因子(integrated toxicity index,ITI),对综合毒性因子进行QSAR分析,得到可直接由硝基芳烃结构参数预测综合毒性因子的单参数QSAR模型。结果表明,QSAR与PCA方法的结合可以成功地评价和预测硝基芳烃的综合毒性。     

毒性比法量化判定芳烃化合物毒性类型的研究

测定了苯酚、硝基苯、间硝基苯胺、对苯二胺、邻苯二酚和氯苯等6种取代芳烃化合物对发光菌（Photobacterium phosphoreum）的急性毒性,应用毒性比（TR）判定方法,同时结合分子结构特征对受试化合物毒性作用进行了探讨和分类．结果表明,氯苯为非极性麻醉型毒性机制,苯酚、硝基苯、问硝基苯胺为极性麻醉型毒性机制,对苯二胺、邻苯二酚为反应性毒性机制．     

硝基芳烃对发光菌及其它水生生物毒性的相关性

测定了硝基芳烃对发光菌的毒性，并研究了它与硝基芳烃对其它水生生物毒性的相关性．结果表明，用发光细菌法能较好地预测鱼、藻等水生生物的毒性。     

十二烷基硫酸钠与取代芳烃对发光菌的联合毒性作用

研究阴离子表面活性剂十二烷基硫酸钠（SDS）和苯酚、硝基苯、甲苯3种取代芳烃对发光菌的单一毒性，以及在等浓度配比条件下，SDS与这3种取代芳烃二元混合体系的联合毒性效应，并采用毒性单住、相加指数、相似性参数和混合毒性指数进行毒性评价。研究结果表明：4种不同的评价方法对SDS与取代芳烃苯酚、甲苯和硝基苯的联合效应评价结果具有较好的一致性，即SDS与苯酚、甲苯的二元混合体系的毒性表现为不同程度的协同作用，而与硝基苯则表现为弱拮抗作用；对环境存在风险性的阴离子表面活性剂SDS，当与一些有毒有害物质共存时会增加该类物质的环境风险性。根据发光原理和混合体系组成，可初步推测联合毒性的作用机制。     

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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