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1.
本文用经典极谱和循环伏安法研究了铋(Ⅲ)-1,2-环己二胺四乙酸(CyDTA)络合物的极谱行为,并用动力可逆波半波电位移动的方法测定了Bi(Ⅲ)-CyDTA络合物的稳定常数和反应自由能等热力学函数。  相似文献   

2.
本文用示波极谱法和新极谱法研究了铍与钍试剂-I络合物的极谱波,用于铍的定量测定浓度范围可至10~(-7)—10~(-8)mol/L.并研究了各种因素对极谱波的影响.用循环伏安法研究了试剂与络合物还原的可逆性.从电位扫描速度与汞滴静置时间两方面研究了试剂和络合物的还原波,证明还原过程受扩散控制,并无明显的吸附作用.  相似文献   

3.
本文探讨了钛(IV)-DCTA络合物在极谱过程中的一些电化学行为,讨论了极谱测定Ti(IV)-DCTA络合物的理论依据,并对迄今未见报导的该络合物稳定常数进行了测定.得到1.在离子强度为0.2M(KNO_3),(25±0.2)℃pH3-5.0,条件下,测得Ti(IV)与DCTA络合物稳定常数为lgk=19.12±0.70;2.确定Ti(IV)与DCTA络合物在极谱过程中两个氢离子参予了电极反应;3.确定了络合物的电极反应电子转移数为n=1;4.并确定了在本文实验条件下,Ti(IV)与DCTA络合物极谱波的可逆情况.  相似文献   

4.
本文用Deford和Hume极谱法测定了25℃、离子强度μ=4.0M条件下Cd~(2+)-Cl~-和Cd~(2+)-SO_4~(2-)络合物的稳定常数。然后以Cd~(2+)作指示离子,用Ringbom和Eriksson间接极谱法测定了同样条件下Ni~(2+)-Cl~-和Ni~(2+)-SO_4~(2-)络合物的组成和稳定常数。  相似文献   

5.
研究了pH为 5 0的醋酸 醋酸钠介质中存在大量锌时 ,镉和钴在丁二酮肟 柠檬酸钠 氯化铵体系中的络合物吸附波 .结果表明 ,镉、钴峰电位分别为 - 0 79V和 - 0 93V ,线性范围分别为 0 0 0 5~ 5mg·L- 1 和 0 0 0 0 1~ 0 1mg·L- 1 ,检测限分别为 4 0× 1 0 - 8mol·L- 1 和 8 1× 1 0 - 1 0 mol·L- 1 .该方法具有不经预处理可直接用于锌电解液中微量镉、钴同时测定的优点 .分析了电活性络合物的组成、极谱波性质和电极过程机理 .镉、钴与丁二酮肟 (DMG)的络合比均为 1∶2 ,Cd(DMG) 2 和Co(DMG) 2 络合物均表现出强的吸附特性 ,且前者吸附性更强 ,峰电流主要由络合物中心离子Cd(Ⅱ )和Co(Ⅱ )还原为Cd和Co产生 ,极谱波均为络合物吸附波  相似文献   

6.
本文建立了Cu(Ⅱ)-Phen体系在单扫描示波极谱仪上测定微量铜的方法。以NH_3-NH_4Cl为底液,pH9.05,Cu(Ⅱ)-Phen络合物有一灵敏导数极谱波。峰电位-0.74V(对SCE).峰电流与铜的浓度在5.0×10~(-7)~8.0×10~(-6)mol/L范围成正比。以该法测定了电镀厂排放污水,获得满意结果。应用循环伏安、脉冲极谱等方法确证了该极谱波为络合吸附波。采用理论计算与条件实验结果相比较的方法,对其电极反应过程做了初步推测。  相似文献   

7.
在pH =4 .7的0 .1mol LHAc - 0 .1mol LNaAc缓冲溶液中,Eu(Ⅲ)与噻吩甲酰三氟丙酮形成的络合物是电活性的,于- 1.6V (vs.SCE)产生较灵敏的极谱峰,检出限为1.0 μmol·L- 1 .利用线性扫描极谱法和循环伏安法探讨了极谱峰的电化学性质及电极反应机理.实验结果表明:Eu(TTA) 3的极谱峰有吸附性质,是不可逆的.  相似文献   

8.
谷胱甘肽-铜极谱络合吸附波的研究   总被引:1,自引:0,他引:1  
在铜离子存在下,谷胱甘肽(GSH)在0.2mol/LNaAc-HAc(pH4.7)缓冲溶液中,与铜离子反应得到谷胱甘肽(GSH)与一价铜离子络合物,在单扫示波极谱上产生一灵敏的络合吸附波,峰电位在-0.59V处(vs.SCE),导数波高与谷胱甘肽浓度在4.0×10-8mol/L~1.0×10-5mol/L范围内分段成线性关系,检测限为1.0×10-8mol/L,相对标准偏差3.3%。研究了极谱波的性质,测得络合物组成为GSH:Cu(Ⅰ)=1:1,表观稳定常数为5.1×1019。  相似文献   

9.
在pH值为10.3的NH3H2O NH4Cl介质中,Fe(Ⅲ)与邻氯苯基荧光酮(以下简称o CPF)生成络合物,于-0.72V(vs.SCE)出现一灵敏的极谱波.铁(Ⅲ)含量在1.0×10-8~1.3×10-6mol/L范围内与峰高呈线性关系,检出限为4.0×10-9mol/L.用多种电化学方法研究了极谱波的性质及电极反应机理,证明-0.72V处的极谱波为络合吸附波,峰电流由中心离子Fe(Ⅲ)还原产生,络合物组成为Fe(Ⅲ)∶o CPF=1∶2,表观稳定常数K稳=5.4×1012.试验了30多种离子对峰电流的影响,并将该体系用于头发中痕量铁的测定.  相似文献   

10.
在5.0×10-3mol/L的盐酸介质中,钼与8-羟基喹啉-5-磺酸生成的络合物在NaNO2存在下,于-0.30V(vs,SCE)出现一尖锐、灵敏的极谱波.钼含量在0.2~400ng/mL范围内与波高呈线性关系,检测限为0.1ng/mL.用多种电化学方法研究了极谱波的性质及电极反应机理,证明络合波为吸附波.峰电流由中心离子Mo( )还原产生,Mo( )与络合剂的组成比为1∶1.方法用于自来水中痕量钼的测定,快速、灵敏、准确,结果满意.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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-  相似文献   

16.
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-  相似文献   

17.
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  相似文献   

18.
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  相似文献   

19.
<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  相似文献   

20.
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