铜(Ⅱ)—麦塔喇红—过氧化氢体系催化光度法测痕量铜的研究

本文研究了在NH_3-NH_4Cl缓冲体系中,痕量铜(Ⅱ)催化过氧化氢氧化麦塔剌红的褪色反应。建立了一种测量痕量铜的新催化光度法,线性范围为0-120ng/ml,检出限为1.64×10~(-10)g/ml,并用于铝合金标样,环境水质标样和人发样中痕量铜的测定。     

双波长双指示剂催化光度法测定中药材中的痕量铜

文章研究在硫酸介质中,利用铜催化过氧化氢氧化甲基橙和亮绿褪色的反应体系.探讨该褪色指示反应的最佳实验条件,在此基础上建立高灵敏度测定痕量铜的动力学分析新方法.通过对该反应催化体系和非催化体系吸光度的测定,确定该体系的最大吸收峰位于波长510 nm和640 nm处.工作曲线的线性范围:0.100~2.00μg/25mL.检出限:3.64×10-9g/mL,相对标准偏差:1.2%.本方法体系稳定,灵敏度高,选择性好,用于亳州道地药材中痕量铜的测定,结果较为满意.     

催化动力学褪色光度法测定痕量铜(Ⅱ)的研究

基于加热和HAC-NaAC缓冲溶液存在下,痕量铜(Ⅱ)能催化高碘酸钠氧化孔雀绿的褪色反应,从而建立了催化高碘酸钠氧化孔雀绿褪色光测定痕量铜(Ⅱ)的新方法.该方法的线性范围4.00-16.00ng/mL铜(Ⅱ),检出限为4.70×10-9g/mL,用于茶叶,菇类中痕量铜的测定,回收率约在97.0%--103.5%之间,结果满意.     

乙腈-NaCl-H2O双水相萃取ICP-AES测定食盐中的铜和铅

研究了乙腈-NaCl-H2O双水相体系的分相条件及在吡咯烷二硫代氨基甲酸铵(APDC)做络合剂时对铜和铅的萃取行为,并结合电感耦合等离子体原子发射光谱仪(ICP-AES)建立了一种测定食盐中铜和铅的方法.该方法在萃取Cu和Pb的同时去除了大量的NaCl基体,从而在ICP-AES测定食盐中痕量Cu、Pb时,去除了高盐的基体干扰.实验中铜和铅的平均回收率分别可以达到106.0%和96.2%,RSD为0.76%和0.83%,计算得出检出限分别为5.0×10-4mg.kg-1和2.3×10-2mg.kg-1,结果令人满意.该方法为高盐样品中金属离子的检测提供了一种新思路.     

可溶有机试剂对ICP-AES测定水质铜的影响

通过对比三种有机试剂检测铜浓度变化的结果,得出了＂采用含5%正丙醇溶液检测时仪器性能条件最佳＂的结论.经相关参数的验证,证明此法的标准曲线线性良好,提高了灵敏度;计算得到的检出限为0.000 4 mg/L,低于现行标准;精密度为0.51%~1.1%,准确度为97.1%~105%,符合检测要求.为准确、有效地检测水中微量铜提供了新的方法.     

偶氮胂K催化动力学光度法测定痕量铜

利用催化动力学光度法测定痕量铜多采用催化氧化动力学光度法和阻抑动力学光度法。笔者利用较少见的还原反应进行痕量铜的测定。研究发现在pH =5 .4的HAc -NaAc缓冲介质中 ,活化剂α ,α’ -联吡啶存在下 ,痕量铜 (II)能强烈地催化抗坏血酸还原偶氮胂K的反应。通过系统地研究反应的最优化实验条件 ,建立了利用还原法催化动力学光度法测定痕量铜 (II)的新方法 ,并计算了反应的活化能和反应速率常数。该方法选择性好 ,灵敏度高 ,是目前测定铜的最灵敏的方法之一。方法的检出限为 5 .4 1× 10 -10 g·L-1,检测范围为 0～ 0 .35 μg铜 (II) / 2 5mL。可用于自来水及食品中的痕量铜 (II)的测定。     

催化褪色光度法测定农产品中的痕量铜

研究了在硫酸介质中痕量铜(Ⅱ)催化过氧化氢氧化乙基紫褪色反应的最佳条件,建立了高灵敏度测定痕量铜的新方法.检出限为6.0×10-10g/mL,线性范围为0.05~3.0μg/(25 mL).使用的仪器设备简单,检测简便、快速.应用于农产品中痕量铜的测定,结果令人满意.     

催化-光度法测定痕量铜

本文以Cu(Ⅱ)对于8-氨基萘酚-3,6-二磺酸与双氧水氧化还原反应的催化作用为基础,提出了一个测定痕量铜(Ⅱ)的灵敏的且有选择性的催化-光度分析法.此法曾用于武汉自来水和武汉东湖水中的痕量铜的测定.试样分析变动系数为6.0%;方法检测极限为6×10~(-11)g(Cu)/ml.     

催化动力学光度法测定痕量铜

在弱酸性介质中,痕量铜可强烈地催化过氧化氢氧化灿烂绿的褪色反应,从而建立了测定痕量铜的催化动力学光度分析新方法.在最佳实验条件下,本法的检出限为8.6×10-9g/mL,线性范围为(0.0-0.2) μg/mL, 用于实际水样中痕量铜的测定,结果令人满意.     

煌焦油兰──过氧化氢体系催化光度法测痕量铜(Ⅱ)的研究

本文研究了在氨性介质中，痕量铜（Ⅱ）催化过氧化氢氧化煌焦油兰褪色反应及其动力条件，建立了一种催化光度法测痕量铜（Ⅱ）的新方法，线性范围为002－10μg／25ml，检出限为39×10－10g／ml．用于环境水标样，铝合金标样中痕量铜（Ⅱ）的测定，结果满意．     

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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