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.     

核固红-溴酸钾催化光度法测定痕量亚硝酸根

在盐酸介质中,亚硝酸根催化溴酸钾氧化核固红,使得核固红在 520 nm处的吸光度明显下降,从而建立了催化光度法测量痕量亚硝酸根的新方法,方法的线性范围为 5× 10-5-50× 10-5 g/L,检出限为 1.27× 10-5 g/L.方法已用于蔬菜中痕量亚硝酸根的测量.     

罗丹明6G共振光散射法测定痕量亚硝酸根

在盐酸介质中,痕量亚硝酸根与罗丹明6G发生亚硝化反应,使罗丹明6G溶液在527nm处的共振散射光强度明显下降,从而建立了共振光散射法测定痕量亚硝酸根的新方法.方法的线性范围为0.02×10-6～0.2×10-6g/mL,检出限为1.22×10-8gm/L.方法用于废水和蔬菜中痕量亚硝酸根的测定,回收率在95.5%～104.9%之间。     

非有机溶剂萃取催化荧光光度法测定痕量亚硝酸根

在磷酸介质中以亚硝酸根催化溴酸钾氧化罗丹明B为研究体系,探讨了该体系在聚乙二醇-2000(PEG-2000)中的萃取催化行为及其影响因素,建立了催化荧光光度法测定痕量亚硝酸根的新方法.结果表明:该方法的检出限为1.65×10-7 g/L,线性范围为0.053-0.23 mg/L,用于测定蔬菜中痕量亚硝酸根的效果良好.     

催化光度法测定水样中的痕量亚硝酸根

研究在磷酸介质中,亚硝酸根催化溴酸钾氧化二甲苯兰FF(XCFF)褪色的新指示反应,建立高灵敏度催化吸光光度法测量痕量亚硝酸根的新方法,确定该催化反应的动力学条件和动力学参数.亚硝酸根的浓度在0.02～15ng/mL范围内时,工作曲线呈良好的线性关系,检出限为4.2×10-12g/mL,此方法用于不同水样中亚硝酸根的测定,结果满意.     

催化动力学光度法测定水中亚硝酸根

本文基于硫酸介质中,亚硝酸根对溴酸钾氧化次甲基蓝的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1.0-3.0μg/25ml、灵敏度为7.56×10-9g/ml用于测定水样中亚硝酸根,效果良好.     

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 .     

亚硝酸根—溴酸钾—溴百里酚蓝体系催化光度法测定痕量亚硝酸根

基于硫酸介质中 ,亚硝酸根对溴酸钾氧化百里酚蓝的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 0 4- 0 36 μg/mL ,检出限量为 8 75× 10 -9g/mL ,用于测定水样中亚硝酸根 ,效果良好     

阿魏酸荧光熄灭法测定痕量亚硝酸根

在pH 5.0的HAc～NaAc缓冲溶液中,阿魏酸与痕量亚硝酸根反应,使得阿魏酸在激发波长358.0nm,发射波长为450.0nm条件下的荧光强度明显下降,其相对荧光强度在一定范围内与亚硝酸根的浓度呈线性关系,从而建立了荧光熄灭法测定痕量亚硝酸根的新方法.方法的线性范围为1.00×10(-6)～8.00×10~(-3)mol/L,检出限为3.47×10~(-7)mol/L.方法已用于环境水样中痕量亚硝酸根的测定,回收率在96.7%～104.5%.     

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.     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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