用三阶导数分光光度法测定原油及渣油中的微量铁

本文介绍了在pH=1.4的KCl-盐酸缓冲溶液中,以5-Br-PADAP为显色剂,用三阶导数分光光度法直接测定原油及渣油中微量铁的方法。本法不加掩蔽剂,利用导数分光光度法具有的抗干扰及高分辨的优点可以消除镍和钒的严重干扰。本法简单、灵敏、准确,在0～26μg/25ml范围内服从比耳定律。经对样品的多次测定和回收实验表明:本法标准偏差小于0.45ppm:相对标准偏差小于5％;回收率为99～109％,与等离子体法测定结果接近,符合测定要求。     

双波长分光光度法同时测定原油及渣油中微量镍和钒

本文提出了以 5-Br-PADAP 做显色剂,在乙醇存在下,在pH=3.4的KHC_8H_4O_4-HCl缓冲溶液内,选择波长对:526nm(λ_2)-646nm(λ_1)(测镍)、620nm(λ_2)-674nm(λ_1)(测钒),用双波长分光光度法同时测定原油及渣油中微量镍、钒的新方法。本法灵敏度高、重复性好。镍、钒服从比耳定律的线性范围均在0～22μg/25ml,回收率在90～119％。经对多种油样的多次测定表明:本法的标准偏差<1.8ppm,相对标准偏差<10％。本测定结果与原子吸收光谱法、等离子体直读光谱法等分析方法的测定结果相符合。     

金胶光度法测定铜钴镍中微量砷

本文研究了金胶光度法测定铜、钴、镍盐中的微量砷。采用氢氧化镧作载体共沉淀砷,Cu~(2+)、Co~(2+)、Ni~(2+)在氨性介质中形成氨配离子被分离除去。砷用锌还原为AsH_3由酸性Au(SCN)_4~-溶液吸收,在保护剂存在下生成红色金溶胶,测量金胶溶液的吸光度便可测定砷。本法测砷,铜、钴、镍试液中含量在0～9μg范围内有良好线性关系.砷的最低检出量在硫酸铜、钴、镍盐中分别为0.36、0.40、0.70ppm。测定饲料微量元素添加物硫酸铜试样,十次测定的标准偏差为0.13,相对标准偏差为2.5％,七次测定的平均回收率大于95％。本法简易、决速、准确、灵敏。文献很少见有用简易光度法测定铜、钴、镍盐中微量砷的报导。     

紫外导数分光光度法直接测定炼厂污水中的挥发酚

本文介绍了一种用紫外四阶导数分光光度法直接测定炼厂污水中挥发酚的新方法。本法省去了萃取、蒸馏和比色等繁琐的预处理和测定步骤,采回水样可以直接测定,20分钟内可测出结果。本法灵敏、准确,测定结果与标准法十分吻合。本法的线性范围为0～32ppm;回收率在93％～108％之间;检出限为0.2ppm.     

高阶导数光度法同时测定原油和渣油中微量镍、钒、铁

在pH为3.0的邻苯二甲酸氢钾-盐酸缓冲溶液存在下,用5-Br-PADAP作显色剂,在水-乙醇介质中用高阶导数光度法同时测定了原油、渣油中微量镍、钒、铁。这种方法灵敏,选择性好,线性范围宽,省时。经过对不同产地的原油,渣油样品进行多次测定表明,这种方法的测定结果与原子吸收光谱法和等离子体直读光谱法的结果相吻合。相对标准偏差小于9％,回收率在90％～105％,符合测定要求。     

用导数分光光度法同时测定微量钴和镍

以5—Br—PADAP为显色剂,用二阶导数分光光度法对微量钴镍进行了同时测定,按“零交法”取569nm和616nm的峰——零导数峰值分别对镍钴定量,服从比耳定律的线性范围分别为0～14μg/25mL和0～22μg/25mL.样品的测定和回收实验表明,该方法准确、灵敏,符合测定要求,与原子吸收法的分析结果相吻合。     

用偏最小二乘法的计算光度法同时测定原油和渣油中的铁、镍、钒

用偏最小二乘法（ＰＬＳ）的计算光度法同时测定了原油和渣油中的微量铁、镍、钒，对测定波长选择问题和抽象组分数的确定方法进行了研究。对模拟石油中铁、镍、钒含量制成的合成样进行了回收实验。结果表明，在铁、镍、钒加入量为０．４～１０μｇ／２５ｍＬ时，其回收率为９４％～１０３％，优于用多元线性回归法的测定结果。     

高灵敏度分光光度法测微量镍

荧光酮类试剂是灵敏度较高的一类金属显色剂,用于分光光度法测定微量金属元素已有报道.但以 BDMAF 作显色剂测微量镍未见报道,本文研究了 Ni 与 BDMAF 的显色反应,在碱性介质中,Ni 与 BDMAF 形成1:4的配合物,配合物可稳定10h 以上,实验结果表明,该体系的灵敏度高,选择性好,用本法可直接测定合金钢中的微量镍.1 实验部分1.1 仪器与试剂     

镍铁合金电镀液中微量钐的二阶导数分光光度法测定

探讨了在弱酸性介质的钐－偶氮胂Ⅲ体系中采用二阶导数分光光度法测定微量钐的方法．本方法具有较好的选择性和灵敏度，检测限达０．２５０ｍｇ／Ｌ，铁、镍等共存离子的允许量可达千倍以上，故可以不经分离或掩蔽而直接测定镍铁合金镀液中的微量钐     

半二甲酚橙——溴化十六烷基吡啶高灵敏度分光光度法测定微量镍

本文研究了在盐酸介质中、半二甲酚橙(SXO)——溴化十六烷基吡啶(CPB)分光光度法测定镍的适宜条件、络合物的组成及杂质干扰情况。制定了用分光光度法直接测定污水中微量镍的方法。该方法准确,灵敏度高,稳定性好,线性范围宽。     

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     

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