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1.
本文研究在碳阳极中添加La,Ce,Pr,Nd,Y等单一稀土化合物对阳极反应超电压的影响。试验结果表明,在工业电流密度范围内,可降低阳极反应超电压0.2~0.34V,节省电能600~1100kW·h/t·Al。文中对电极的电化学反应过程进行了研究,得到阳极反应的动力学方程,推导出稀土物料作为电催化剂的反应机理和作用模型。为了降低催化剂成本,可采用混合稀土代替单一稀土。  相似文献   

2.
电解炼铝采用不消耗的情性阳极有可能把目前的能耗减少20%。介绍了组成(重量%)为96%SnO_2%Sb_2O_2%CuO 的 SnO_2基情性电极的制备与掺杂方法.用稳态恒电位法及脉冲技术,对1000℃下2.7NaF·AlF_3-Al_2O_3(饱和)熔体中 SnO_2基情性阳极上氧析出的超电压作了测定.发现掺有微量 Ru,Fe 和 Cr 的电极具有明显的电催化作用。以掺 Ru 者最显著,在1.0安培/厘米~2下,其上超电压仅及未掺杂者的1/3。在电流密度高达4.0安培/厘米~2时也小于0.15伏。上述掺杂电极比相同条件下 Pt 阳极上的超电压为低。  相似文献   

3.
分析了影响电力静电感应晶闸管阻断电压BVAK的因素,提出了提高BVAK的方法,并构造了几种阳极结构.在实验了3种结构的基础上,给出一种新阳极造型.它有效利用了外延过程中在p-阳极区形成的轻掺杂n-层,在该层上进行条形p 重掺杂,为正向导通过程提供空穴注入,从而实现电导调制,降低通态压降.而未掺杂的透明阳极区则形成电流漏.实验表明,该结构不仅能有效增大阻断电压,同时利于关断过程积累电荷的抽取,加快关断时间,降低关断损耗.  相似文献   

4.
通过金属有机物分解的方法合成了Ti掺杂Fe_2O_3光阳极.通过XRD、紫外—可见吸收光谱、X射线光电子能谱(XPS)、扫描电镜(SEM)对Fe_2O_3光阳极进行表征,并对Fe_2O_3光阳极进行了光电化学表征.为了提高Ti掺杂Fe_2O_3光阳极的光电性能,对Ti掺杂Fe_2O_3光阳极的Ti掺杂浓度进行了优化.光电化学测试结果表明电化学表面处理能够提高Ti掺杂Fe_2O_3光阳极的光电化学性能.说明Ti掺杂和电化学表面处理可以增加Fe_2O_3光阳极光电流.基于Mott-Schottky曲线和电化学阻抗谱(EIS)分析了Fe_2O_3光阳极光电流增加的机理.  相似文献   

5.
通过金属有机物分解的方法合成了Ti掺杂Fe_2O_3光阳极.通过XRD、紫外—可见吸收光谱、X射线光电子能谱(XPS)、扫描电镜(SEM)对Fe_2O_3光阳极进行表征,并对Fe_2O_3光阳极进行了光电化学表征.为了提高Ti掺杂Fe_2O_3光阳极的光电性能,对Ti掺杂Fe_2O_3光阳极的Ti掺杂浓度进行了优化.光电化学测试结果表明电化学表面处理能够提高Ti掺杂Fe_2O_3光阳极的光电化学性能.说明Ti掺杂和电化学表面处理可以增加Fe_2O_3光阳极光电流.基于Mott-Schottky曲线和电化学阻抗谱(EIS)分析了Fe_2O_3光阳极光电流增加的机理.  相似文献   

6.
在原有的浸渍法掺杂碳阳极的基础上,全面考察了机械混合法掺杂碳阳极的掺杂剂制备和掺杂效果,并将其与浸渍法掺杂进行了比较.结果表明,机械混合掺杂法较浸渍法有明显的优势,但其电催化效果受到了一定的限制  相似文献   

7.
微生物燃料电池(MFC)作为一种新能源,符合人们绿色环保、可持续发展的发展理念,在MFC中,阳极材料与菌体之间的电子传递情况是制约其性能提升的主要因素.本文主要探索了方便快捷的电化学方法所得到的聚苯胺修饰阳极碳毡电极对MFC产电性能的影响情况.通过扫描电镜可以观察到阳极碳毡电极表面形成了具有一定形态的聚合物.对MFC的电压数据进行分析,表明修饰聚苯胺的碳毡电极最大输出电压可达到(330±5) mV,比对照组的空白碳毡电极提高了365%;且其最大功率密度达到了(425±5) mW·m~(-2),是对照组的6倍.实验结果表明:电化学聚苯胺修饰电极可有效利用聚苯胺导电性好、生物相容性高的优点提高MFC的产电性能.  相似文献   

8.
铝电解生产中,碳素阳极两组分(石油焦和沥青结焦)的活性差异带来阳极的选择性氧化,是造成碳素阳极过量消耗的主要原因之一.基于阳极中杂质或添加剂对阳极活性产生的影响,作者采用分别测定石油焦和沥青结焦与CO2反应活性的实验方法,研究了AlF3及其它5种添加剂(分别用A,B,C,AlF3+C,AlF3+D代替)对二者活性的影响.结果表明,添加剂C提高了沥青结焦和石油焦的CO2反应活性;添加剂AlF3,A,B,A1F3+C及AlF3+D均可不同程度地降低沥青结焦和石油焦的CO2反应活性,并且使沥青结焦与石油焦的CO2反应活性差距缩小,使得有可能在碳阳极中采用适宜添加剂,减缓其选择性氧化,降低阳极碳耗.  相似文献   

9.
采用机械掺杂法制备了掺有不同复合氧化物粉末的碳阳极,并测试了熔融状态下Na3AlF65% Al2O3 熔体对不同掺杂电极的润湿性.实验结果表明,掺有LiAlO2 和CaAl2O4 的碳阳极对熔盐显示了较好的润湿性.  相似文献   

10.
本实验采用共沉淀法,以无机盐SnCl4·5H2O、Sb2O3、Gd(NO3),为前驱体,制备了含SnO2中间层的稀土Gd掺杂SnO2/Sb多组分涂层阳极。研究了以苯酚为目标有机物的电化学降解特性,以考察SnO2中间层对稀土Gd掺杂SnO2/Sb涂层阳极性能的影响;并对所制备的涂层阳极进行了SEM、XRD、XPS、EDX等表征及循环伏安曲线测试,分析并讨论了SnO2中间层对稀土Gd掺杂SnO2/Sb阳极性能的影响机理。结果表明:SnO2中间层对稀土Gd掺杂SnO2/Sb电极稳定性有较大提高,对该电极的电催化性能略有提高。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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  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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