锌电积用铝基β-PbO2复合材料的性能研究

在Al/Pb/α-PbO2-WC表面恒电流电沉积制备了β-PbO2-WC（Co3O4）复合沉积层,获得了Al/Pb/α-PbO2-WC/β-PbO2-WC（Co3O4）复合材料.考察了WC（碳化钨）、Co3O4（四氧化三钴）颗粒的掺杂对β-PbO2 复合材料物理性能及其在锌电积模拟体系中的耐蚀性、析氧电催化活性、交流阻抗特性的影响.结果表明：WC与Co3O4 颗粒在β-PbO2 中的掺杂提高了复合材料的显微硬度,降低了电阻率及锌电积模拟体系中的析氧过电位,增强了锌电积模拟体系中的耐腐蚀性能.     

Mn2+掺杂不锈钢基β-PbO2电极制备及电催化性能

在硝酸铅镀液中添加Mn(NO3)2,直流电沉积方法制备不锈钢基β-PbO2电极.利用SEM、EDS表征电极的形貌和Mn含量,阳极极化曲线和动力学参数表征电极的电催化活性.结果表明:Mn(NO3)2的添加量为6g/L时,表面形貌为颗粒状,排列紧凑,其电催化活性最好.掺杂Mn2+制备的不锈钢基β-PbO2电极与Pb-(1%)Ag合金阳极相比,槽电压降低,电流效率提高.     

Ti/α-PbO2/β-PbO2电极电催化氧化处理苯酚废水

采用电催化氧化法,以自制Ti/α-PbO2/β-PbO2电极为阳极,在室温条件下对苯酚模拟废水进行降解研究,探讨电流密度、电极间距、pH值及苯酚初始质量浓度对苯酚降解效率的影响规律.结果表明,在电流密度为600 A·m-2,电极间距为1.0 cm,pH值为3,苯酚初始质量浓度为100 mg·L-1的条件下,苯酚降解效率达92%以上.紫外光谱等实验结果表明,苯酚在氧化降解过程中会产生苯醌等中间产物,苯酚及其中间产物最终被矿化为CO2和H2O.     

有机物种类对恒电位电解法测定COD值准确性的影响

以β-PbO2/石墨电极为工作电极,在支持电解溶液中加入一定量待测有机物,在低于析氧电位下进行恒电位电解时,因电极表面吸附态羟基自由基的消耗速率受电解质溶液中有机物分子向电极表面的扩散过程控制,表现为阳极电流强度的增加值(ΔI)与有机物质量浓度ρ之间呈线性关系。本文研究了多种待测有机物的ΔI与ρ的线性关系,发现由于有机物种类不同造成羟基自由基消耗速率不同,因而线性比例系数有所不同。实验结果表明在测定混合水样的化学需氧量(COD)值时,应采用与待测水样具有相似有机物混合比例的标准溶液制作工作曲线,以减少测量误差。     

PbO2电极的改性及非均相电催化氧化废水中的硝基苯

使用热分解 电镀法制备Ti基PbO₂电极（Ti/PbO₂）、 F^-掺杂Ti基PbO₂电极（Ti/F-PbO₂）和F^-,La³⁺共掺杂Ti基PbO₂电极（Ti/F-La-PbO₂）, 并通过扫描电镜(SEM)表征Ti/F-PbO₂电极和Ti/PbO₂电极的表面结构, 用X射线衍射(XRD)测试分析Ti/PbO₂电极、 Ti/F-PbO₂电极和Ti/F-La-PbO₂电极的晶相. 通过加速电解寿命和电催化降解废水中硝基苯的实验, 研究F-掺杂和F^-,La^3+共掺杂对PbO₂电极稳定性及电催化活性的影响. 使用SEM和XRD测试分析了Fe³⁺/MgO的表面结构及晶型, 并将自制Fe³⁺/MgO催化剂应用于电催化处理废水中硝基苯的实验体系, 探讨了电解体系中相关因素和催化剂用量对废水中硝基苯及化学耗氧量(COD)去除率的影响. 结果表明:  La³⁺掺杂使电极镀膜表面晶粒细化; 不同掺杂均影响晶体生长的晶面取向; F^-掺杂提高了PbO₂阳极的电解寿命; La³⁺掺杂改善了PbO₂电极的导电性能; Ti/F-La-PbO₂电极的电催化降解活性显著提高; 在电解体系中, 催化剂显著提高了电解反应速率和COD及废水中硝基苯的去除率; 硝基苯的降解符合一级反应动力学.     

Li2SO4质子传导膜H2S固体氧化物燃料电池研究

制备和研究了具有H2S,(MoS2 NiS Ag)/Li2SO4 Al2O3/(NiO Ag),air结构的H2S固体氧化物燃料电池用于产生电能和脱除燃料气体中的H2S.电池在600～650 ℃和大气压下运行.燃料电池的电化学性能受电解膜的组成,电极材料和操作温度影响.掺杂了Al2O3 和少量H3BO4的Li2SO4质子传导膜可以提高膜的机械强度和性能,改善膜的致密性和电池的性能.适宜的Li2SO4 和 Al2O3 比为3～4∶1(质量比), 适宜掺杂H3BO4的量为2%～5%(w).掺杂了Ag粉和电解质的金属硫化物复合阳极在H2S气流下很稳定和性能很好, 掺杂了Ag粉和电解质的的NiO复合阴极在去除H2S时性能优于Pt电极催化剂.在650 ℃电池的最大输出功率密度为70 mW·cm -2,最大电流密度为180 mA·cm -2.然而,电池长期运行的稳定性实验仍有待研究.     

贵金属氧化物电极电解处理有机废水

对经热分解法制备所得Ti基IrOr-Ta2O5涂层电极及掺杂Sn，Pb的三元氧化物电极电解处理染料厂废水及模拟有机废水进行了研究．COD测试结果表明，使用IrO2-Ta2O5／Ti电极可以电解去除废水中的有机物．随电解时间增加废水COD值降低，高COD值时电解效率高，COD值很低的有机废水中加入NaCl对电解去除有机物有很好的促进效果．电极掺杂第三元素Sn，Pb可以促进电解去除废水中的有机物，与IrO2-Ta2O5/Ti相比，PbO2/IrO2-Ta2O5／Ti电极电解废水的COD去除率提高了11．2%。     

软锰矿粒子电极处理SMP模拟废水实验研究

将软锰矿粒子电极引入三维电极系统处理钻井废水中难降解有机物。考察电解质和相关运行条件对CODCr去除率和活性氯生成量的影响。实验表明:Na Cl作支持电解质时CODCr去除率明显优于Na2SO4,电解产生的活性氯能进一步促进有机物的氧化降解。软锰矿粒子电极能显著提高活性氯的生成量和电流效率。以Na Cl为电解质,在电导率3600μs/cm、p H值7.0、粒子电极投加量80 g、电流强度0.9 A、曝气600 m L/min、电解40 min的实验条件下电解SMP模拟废水,CODCr去除率可达61.50%。     

中温质子传导膜H2S燃料电池电极催化剂

研究了基于三相边界层理论设计的中温质子传导膜H2S燃料电池的阳极与阴极催化剂.考察了3种阳极催化剂Pt、MoS2及复合金属硫化物(MoS2/N iS)电化学氧化硫化氢的性能和在硫化氢环境下的化学稳定性,发现MoS2和复合MoS2/N iS催化剂比Pt具有更好的催化活性,但MoS2在温度超过450℃时会升华,而含有Mo和过渡金属N i的复合MoS2/N iS催化剂在操作条件下很稳定.文中还研究了两种阴极催化剂Pt与复合N iO催化剂的电化学性能,发现复合N iO催化剂比Pt电极具有更低的过电位和更好的电化学性能;虽然复合电极的导电性比Pt差些,但是这一问题可以通过在电极中掺杂10%的Ag粉解决.由H2S、(MoS2 N iS Ag 电解质 淀粉)/Li2SO4-A l2O3/(N iO Ag 电解质 淀粉)、空气构成的燃料电池在101.13 kPa和600~680℃下的电化学特性研究表明,电池最大输出电流密度和功率密度在680℃时分别达到240mA/cm2和70mW/cm2.     

粉体MnO2电极的循环伏安研究

用循环伏安法对粉体MnO_2(包括电解MnO_2和天然锰矿)电极在KOH水溶液中进行了研究,讨论并确定了实验条件。结果表明,电解MnO_2与天然锰矿由于结构不同,在碱性溶液中氧化还原的机理也不同;电解MnO_2→Mn_2O_3→Mn(OH)_2,而天然锰矿则一步还原成Mn(OH)_2。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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