大气中二氧化硫的分析

采用还原分光光度法对大气中的二氧化硫进行了测定.通过一系列单一条件实验确定了还原反应发生的最佳体系.在反应体系中微量二氧化硫能迅速还原三价铁为二价铁,使邻二氮菲-铁(Ⅱ)配合物浓度增加,以此测定二氧化硫的含量.实验发现邻二氮菲-铁(Ⅱ)红色配合物经有机溶剂异戊醇萃取后,其吸光度增大,测定的灵敏度提高,最大摩尔吸光系数(ε)由原来的9.93×104L(cm.mol)-1增大到1.13×105L(cm.mol)-1.检出限为0.008 6μg/mL,RSD为1.6%.方法简便灵敏,精密度高,线性关系达0.999.将该法用于大气中二氧化硫的测定,获得满意的结果.     

电导法测定大气中微量二氧化硫

本文采用电导法对大气中微量二氧化硫的测定进行了系统的研究,并用四氯汞盐-盐酸副玫瑰苯胺比色法与电导法进行对比实验,两者基本吻合.实验结果表明本方法准确,可靠,简便,快速和无毒,同时表明方法精密度和线性关系均令人满意.样品的平均加标回收率为95.85%.     

用汞取代法测定大气中痕迹量SO_2的研究

国内外对二氧化硫污染大气的监测已作过大量研究,提出了许多方法。但多因仪器的灵敏度不高,实际应用时不得不大大增加取样体积,既延长了分析时间,又给正确评价大气质量带来一定困难。最近,美国G.Marshall和D.Midgley提出了一种全新的测定大气中痕迹量二氧化硫的汞取代法。我们利用国产仪器对这一方法进行了系统实验。 汞取代法测定大气中二氧化硫的主要反应式如下:     

改进测定生活饮用水中微量氰化物方法的研究

采用漂白粉制取有效氯溶液代替氯胺T,对生活饮用水中微量氰化物的测定方法作了改进。该方法测定饮用水中微量氰化物简单易行,精密度、准确度高。     

黑糯米中微量金属元素的原子吸收光谱测定

本文对惠水黑糯米等粮食样品中的微量金属元素含量的原子吸收光谱测定方法的研究,给出一种能连续测定11种(Cu、Zn、Fe、Mn、Ca、Na、Mg、K、Pb、Cd、和Cr)元素的定量方法。并利用国家粮食标准样品测试以验证方法的准确度,证明所给该法准确可靠,可推广应用于其他粮食样品中微量金属元素的测定。     

大气中氮氧化物和二氧化硫高效液相色谱分析的研究思路

本文介绍了近几年硝酸根、亚硝酸根、亚硫酸根等离子的测定方法的进展 ,并通过对现有方法的比较 ,指出了目前这些方法的局限性 ,提出了利用高效液相色谱仪监测大气中氮氧化物和二氧化硫的新思路     

大米中微量氟的测定

本文通过条件实验的选择,给出了采用离子选择电极法测定大米中微量氟的测定方法和条件。该方法具有一定的实用价值,同时适用于其它粮食样品中氟的测定。     

红花银桦对大气氟、硫污染的抗性影响探讨

以红花银桦（Grevillea banksii）为材料,选取了不同区域进行试验,栽培10个月后对红花银桦叶片氟、硫含量进行了测定,同步测定了大气氟、硫含量。结果表明,两试验点大气氟含量均低于国家二级标准,但两试验点大气存在一定程度二氧化硫污染,五星点最高超过国家二级标准达11倍多。不同区域植物叶片氟、硫含量有明显的差异,叶片氟、硫累积量与大气中氟、硫含量存在密切相关性;而植株生长正常,说明红花银桦对二氧化硫污染的大气具有较强的忍耐和抵抗能力,同时具有较强吸收净化氟化物、硫化物的能力。     

电量法测定微量水的卡尔·费休电解液的实验研究

电量法测定微量水时，卡尔·费休试剂配制的电解液的组成对微量水的测定具有重要意义。本文研究了卡尔·费休试剂中碘、二氧化硫和电解液中甲酰胺的浓度对反应速率的影响。并得到了卡尔·费休试剂配制的电解液中碘、二氧化硫、甲酰胺和乙二醇的最佳浓度范围。按最佳配方得到的阴极液和阳极液用于微量水的测定，相对标准偏差为±２％。     

二氧化硫测定废液中氯化汞的回收

大气二氧化硫测定废液中的氯化汞造成环境污染。本文提出对含汞废液中的氯化汞进行回收，重新应用于大气二 氧化硫的测定，减少废液对环境的污染，用回收氯化汞配制的吸收液能满足测定要求。     

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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