甲氨蝶呤在Co/GC离子注入修饰超微电极上的电化学行为

甲氨蝶呤 (MTX)在 0 0 0 5mol·L-1 Tris 0 0 5mol·L-1 NaCl(pH7 12 )缓冲溶液中 ,用Co/GC离子注入修饰超微电极进行伏安测定 ,得到一良好的还原峰 ,峰电位Ep=- 0 978V(vs.SCE) .峰电流ip 与MTX的浓度在 8 0× 10 -8～ 9 6× 10 -6mol·L-1 范围内成线性关系 ,检出限为1 0× 10 -8mol·L-1 .基于此建立了测定MTX的新方法 .用于市售药片测定 ,回收率在 98 9%～10 6 2 %之间 .用线性扫描和循环伏安法研究了体系的电化学行为及电极反应机理 .实验表明 ,MTX的还原为不可逆吸附过程 ,并伴随 2个电子参与电极反应 .经扫速对催化效率的影响实验证明体系存在催化作用     

甲氨蝶呤的电化学行为及应用的研究

在 0 .1mol·L- 1NH3 NH4 Cl (pH 9.8)缓冲溶液中 ,甲氨蝶呤在单扫示波极谱上有一灵敏的导数极谱峰 ,峰电位Ep=- 0 .83V(vs .SCE) .峰电流ip 与甲氨蝶呤的浓度在 5 .4× 10 - 8～ 6.5× 10 - 6 mol·L- 1范围内成线性关系 ,检出限为 4 .33× 10 - 8mol·L- 1.基于此建立了单扫示波极谱测定甲氨蝶呤的新方法 ,用于市售药片的测定 ,回收率在 92 .9%～ 10 6.8%之间 ,结果令人满意 .用线性扫描和循环伏安法研究了体系的电化学行为及电极反应机理 ,实验表明 ,甲氨蝶呤的还原属于具有吸附性的准可逆过程 ,并伴随 2个电子、2个氢离子参与电极反应 .     

甘氨酸的荷移分光光度法测定

文章用分光光度法研究了甘氨酸与四氯苯醌 ( TCBQ)的荷移反应 ,确定在 p H=9.0的硼砂缓冲溶液中 ,于 5 0℃水浴中恒温 60 min,可获得 1∶ 1的络合物 ,其λmax=35 0 nm,表观摩尔吸光系数 ε=1 .98× 1 0 4 L· mo L- 1· cm- 1线性范围为 0～ 2 .7× 1 0 - 5mo L/L.应用拟定的方法测定了甘氨酸制剂的含量 ,结果与文献方法一致 ,回收率为 95 .0 %～ 1 0 4 .2 %相对标准偏差为 0 .79% .     

铑—1—（2—吡啶偶氮）萘酚络合吸附波测定微量铑

铑和 1- (2 -吡啶偶氮 )萘酚 (PAN)在 p H=5.0 0的邻苯二甲酸氢钾—氢氧化钠介质中生成具有电活性的络合物 ,在单扫示波极谱 - 0 .6 7V(vs.SCE)处呈现良好极谱还原波 .该波二阶导数峰高与铑的浓度在 2 .3× 10 -8～ 4 .8× 10 -7mol· L-1和 4 .8× 10 -7～ 9.7× 10 -6mol· L-1范围内呈线性关系 ,检出限为 7.6× 10 -9mol· L-1,并成功的用于贵金属合成样及合金样品中铑含量的测定 .实验结果表明该极谱波属络合吸附波     

丹皮酚的伏安行为及其应用

在 pH =7.8的NaOH KH2 PO4 底液中 ,用单扫示波极谱法可以得到一灵敏的丹皮酚导数还原峰 ,其峰电位Ep=- 1.6 5V(vs .SCE) .峰电流与丹皮酚的浓度在 4 .0× 10 - 7～ 1.0× 10 - 5mol·L- 1范围内呈线性关系 (r =0 .9998) ,检出限为 2 .0× 10 - 7mol·L- 1.该法用于牡丹皮中丹皮酚质量分数的测定 ,结果令人满意 .用线性扫描和循环伏安法研究体系的行为 ,结果表明 ,其电极过程为具有吸附性的不可逆过程     

西瓜花叶病毒-2新疆株的纯化

研究了西瓜花叶病毒 2新疆株的纯化 .感病西葫芦叶组织在含有w =0 .2 %巯基乙醇和 0 .0 1mol·L- 1乙二胺四乙酸二钠 (EDTA)的 0 .5mol·L- 1的磷酸钾缓冲液中匀浆 ,用匀浆体积 1/4的氯仿澄清 ,粗提取液中的病毒经含有 φ =1%TritonX 10 0和w =3%NaCl的w =6 %聚乙二醇沉淀 ,并以含有 0 .5mol·L- 1尿素、w =0 .1%的巯基乙醇和 0 .0 1mol·L- 1EDTA的 0 .5mol·L- 1磷酸钾缓冲液悬浮 ,后经含有w =0 .1%巯基乙醇和 0 .0 1mol·L- 1EDTA的w =10 %～ 4 0 %蔗糖密度梯度离心 ,获得了经电子显微镜、紫外检测和接种试验证实侵染活性为 94 .8%的纯化病毒 .纯化病毒的A2 6 0 /A2 80 =1.2 1,A2 6 0 /A2 4 5=1.15 ,纯化病毒产量约为每kg西葫芦感病叶组织中可提取 16mg .     

催化极谱法快速测定硫磺中微量碲

采用硫化铵快速分解硫磺试样,在16.56 mol·L-1NH3·H2O-0.21 mol·L-1酒石酸钠-3.01×10-4mol·L-1Pb-1.50×10-2mol·L-1EDTA-0.12mol·L-1Na2SO3-3.2×10-4mol·L-1HNO3体系中以催化极谱法测定微量碲.极谱峰电位为-1.10V(VS·SCE).碲浓度在4～100ng/mL-1范围内与峰电流有良好的分段线性关系.检出下限为4ng·mL-1.方法的RSD为1.9%～2.3%,加标回收率为90.10%～96.00%.该法操作简便快速,用于硫磺样品的测定结果满意.     

分光光度法测定Fe(Ⅲ)-二甲酚橙显色反应的研究

在 5× 10 -2 mol·L-1HCl溶液中 ,二甲酚橙与Fe(Ⅲ )生成紫红色络合物 ,其最大吸收波长位于5 6 0nm处 ,表观摩尔吸光系数ε =2 .0× 10 4L·mol-1·cm-1.Fe(Ⅲ )含量在 0～ 2 .4mg·L-1范围内符合Beer定律 .用于水样中微量铁 (Ⅲ )的测定 ,结果较满意     

一种测定工业废水中Hg^2＋的新方法

研究了碱性染料亚甲基蓝 (MB)同 KBr与 Hg2 络合形成的稳定络合物用于分光光度法测定 Hg2 的方法。在柠檬酸 -硫酸缓冲介质 p H=3 .8的条件下 ,络和物的最大吸收波长λmax=6 5 7nm,表观摩尔吸光系数 ε=1 .0 6× 1 0 5L· mol- 1· cm- 1 ,该络和物的组成为 n(Hg2 )∶ n(Br- )∶ n(MB) =1∶ 3∶ 1 ,线形范围为 0 .0 1 8～ 0 .80 0 μg·m L- 1。具有灵敏度高、稳定性好的特点。并对实际水样进行了测定 ,结果可靠。     

Eu(Ⅲ)-ARS络合物的极谱吸附波研究

研究了在 p H=9.6的氨 -氯化铵缓冲溶液中 ,Eu( )与茜素红 (ARS)络合物的极谱波 ,该极谱波峰电位在 -2 .2 5 V(sv. SCE) ,其峰电流与铕的浓度在 3 .0× 1 0 - 6 ～ 3 .0× 1 0 - 4 mol· L- 1 之间呈线性关系 ,最低检出限为 1 .0× 1 0 - 6 mol· L- 1 。利用该方法可测定稀土矿石中的中稀土元素铕     

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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