溴酸钾氧化溴酚蓝催化光度法测定亚硝酸根

以磷酸介质中亚硝酸根催化溴酸钾氧化溴酚蓝为指示反应,通过条件选择,建立了催化光度法测定痕量亚硝酸根的新方法.在90℃恒温水浴中加热反应10min,测定亚硝酸根的线性范围为0.01～0.60μg/25mL,测定下限低达8×10-11g/mL.所拟定分析方法已直接应用于环境水样中超痕量亚硝酸根的测定.     

溴酸钾氧化酚藏花红催化光度法测定痕量亚硝酸根

在硫酸介质中 ,根据亚硝酸根对溴酸钾氧化酚藏花红的褪色反应具有较强的催化作用 ,建立了一种催化光度法测定痕量亚硝酸根的新方法 .本法的线性范围为 0 .36～ 0 .5 6 μg/mL、检出限为 2 .44× 10 -8g/mL ,具有良好的选择性 .用于测定雨水中痕量亚硝酸根 ,其相对标准偏差为 2 .8%～ 3.5 %,水样加标回收率为 98%～10 2 %,结果满意 .     

食品中亚硝酸根的荧光动力学分析法

在酸性介质中,亚硝酸根能够催化类Fenton试剂氧化罗丹明B使其荧光猝灭,据此建立了催化动力学荧光法测定痕量亚硝酸根的新方法.系统研究了反应时间、温度、反应介质及各试剂的最佳用量以及共存物的干扰情况.在最佳条件下,该方法的线性范围为0.040～0.480μg/mL,检测限为0.033μg/mL,直接用于鱼干、肉制品等食品和环境水样中痕量亚硝酸根的测定,回收率94.3%～105.7%.     

反相流动注射催化光度法测定超痕量亚硝酸根

在酸性介质中,以丙三醇为增敏剂与消泡剂,研究了亚硝酸根对溴酸钾氧化结晶紫反应的催化作用及其动力学条件,建立了催化动力学光度法测定超痕量亚硝酸根的新方法.方法检出限为0.02μg/L,测定的线性范围为0.05～5 0μg/L,对于浓度为0.2μg/L和2 0μg/L的亚硝酸根测定的相对标准偏差分别为1.8%和1.1%,分析速度为72样/h.利用此法测定了药片、蔬菜及环境水中的亚硝酸根,与经典的盐酸萘乙烯二胺比色法分析结果基本一致.     

溴酸钾-藏红T光度法测定痕量亚硝酸根

研究了在磷酸介质中 ,由于亚硝酸根催化作用 ,溴酸钾能够氧化藏红 T使之褪色 ,建立了测定痕量亚硝酸根的新方法 ,并探讨了这一催化反应的动力学条件 .其线性范围为 0～ 5.6 μg/ L,检出限为 2 .0× 1 0 - 8g/ L.用于纯净水中的亚硝酸根测定 ,结果满意     

动力学分光光度法测定痕量亚硝酸根和硫氰酸根的研究

基于亚硝酸根对溴酸钾氧化乙基橙反应的催化作用及硫氰酸根对此反应的抑制作用，建立了动力学光度法测定痕量亚硝酸根和硫氰酸根的新方法，测定亚硝酸根的线性范围为5～100μg／L，测定流氰酸根的线性范围为3～12μg／L，用于湖水和蔬菜中的亚硝酸根含量及化学试剂和尿中的硫氰酸根测定，结果满意．     

催化动力学光度法测定亚硝酸根

研究了在磷酸介质中,亚硝酸根催化碘酸钾氧化偶氮胂Ⅰ褪色反应的适宜条件与影响因素,建立了动力学光度法测定痕量亚硝酸根的新方法.方法线性范围为0~80.0μg/L,检出限为0.68μg/L.该催化反应用于水样中亚硝酸根的测定,结果满意.     

双波长双指示剂催化动力学光度法测定痕量亚硝酸根

在磷酸介质中,利用亚硝酸根催化溴酸钾氧化亮绿和甲基橙褪色的指示反应,建立催化光度法测定痕量亚硝酸根的新方法.该反应的最大吸收峰在500 nm和640 nm处,线性范围1-11μg/25 mL,其检出限为2.82 × 10-10g/L,相对标准偏差0.05%.本方法灵敏度高,体系稳定,具有较好的选择性,用于自来水中痕量亚硝酸根的测定,结果较为满意.     

催化动力学光度法测定痕量亚硝酸根

研究在稀盐酸介质中,亚硝酸根对溴酸钾氧化罗丹明B褪色的催化反应,建立测定痕量亚硝酸根的催化反应光度法.该方法测定亚硝酸根的最大吸收波长540nm,表观摩尔吸光系数为2.9×105L·mol-1·cm-1.方法检出限为8.27×10-10g·mL-1在0～6.5μg/25mL范围内符合比耳定律,用于水果、蔬菜、肉制品、罐头样品中痕量亚硝酸根的测定,结果满意.     

阻抑动力学分光光度法测定痕量碘

研究了在稀硫酸介质中,痕量碘离子对亚硝酸根催化溴酸钾氧化百里香酚蓝的阻抑作用,建立了测定痕量碘离子的阻抑动力学光度分析的新方法.测定碘离子的线性范围为:0～0.32μg/mL,检出限为8.96×10-8g/mL.用于药品中的微量碘的测定,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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