SPE电极上Pt单组分及Pt—Au双组分还原态CO2阳极剥离 …

采用循环伏安法,对ＳＰＥ Ｐｔ电极以及ＳＰＥ Ａｕ－Ｐｔ电极上还原态ＣＯ２的电化学氧化行为研究表明,此类电极的电化学特性与光滑Ｐｔ电极一致：ＣＯ２在氢原子吸附电位区０￣２５０ｍＶ（ｖｓ．ＲＨＥ）处,可与电极上化学吸附的氢反应,生成还原态的ＣＯ２,通过线性扫描,还原态ＣＯ２即发生一不可逆电化学氧化过程（阳极剥离）。在ＳＰＥ Ｐｔ系列及ＳＰＥ Ａｕ－Ｐｔ系列上ＣＯ２的电化学行为表明,当ＳＰＥ Ｐｔ系列     

铝在 KOH 溶液中析氢行为的电化学研究

通过恒电位集气、极化曲线和交流阻抗的方法研究了铝在ＫＯＨ溶液中阴极析氢的电化学行为,推导了铝电极表面可能的析氢基元反应过程．铝电极表面析氢过程以单电子转移步骤为控制步骤,理论得出的阴极析氢的Ｔａｆｅｌ斜率和实验得到的Ｔａｆｅｌ斜率基本一致,由交流阻抗方法计算的和曹氏弱极化曲线拟合电化学反应参数ｂｃ值相等,说明交流阻抗方法可以消除溶液电阻对极化曲线的影响．     

酞菁铁—表面活性剂薄膜修饰电极及其催化性能

将酞菁铁（ＦｅＰｃ）掺入阳离子表面活性剂双十二烷基二甲基溴化铵（ＤＤＡＢ）的氧仿溶液，并涂布于热解石墨电极表面，待氯仿挥发后即制得ＦｅＰｃ－ＤＤＡＢ薄膜电极，循环伏安实验表明，在ＫＢｒ溶液中该薄膜电极有２对还原氧化峰，第１对峰的Ｅｐｃｌ＝－０．６４Ｖ，Ｅｐａｌ＝－０．２９Ｖ（ｖｓ．ＳＣＥ）第２对峰的Ｅｐｃ２＝－１．０４Ｖ，Ｅｐａ２＝－０．９４Ｖ着重探讨了第２对峰的电化学行为，估计了该体系的电化学参     

血清白蛋白在裸银电极上的直接电化学行为

本文研究了牛血清白蛋白在裸银电极上的直接电化学行为，在ＰＨ＝７．０的ＫＨ２ＰＯ４－Ｋ２ＨＰＯ４缓冲 溶液中，ＢＳＡ在裸银电极上有一对淮可逆的氧化还原峰，当扫描速度为２０ｍＶ／ｓ．ＢＳＡ浓度为１．２＊１０＾＆－７ｍｏｌ／Ｌ时，峰电位分别为＋０．２０Ｖ和＋０．０５Ｖｖｓ．ＳＣＥ。     

HAsO2在金电极上的阴极还原行为

采用环盘电极实验和交流阻抗技术等研究了ＨＡｓＯ２在硫酸钠溶液（ＰＨ＝４．０）中在金电极上的阴极还原行为。结果表明,ＨＡｓＯ２可以最终还原为ＡｓＨ３,整个还原过程可以分为两步：ＨＡ２Ｏ２还原为金属Ａｓ的金属Ａｓ进一步还原成ＡｓＨ３,在电极上的吸附较强,溶出性能较差。这两步还原过程在阻抗的复数平面图上呈现二个明显的电容弧,利用ＥＱＵＩＶＣＲＴ软件对其进行计算机拟合,得到了对应的等效电路以及其中的反应电     

高比表面NiMo—RuO2复合催化层析氢电极

报道了ＮｉＭｏ－ＲｕＯ２复合催化层的制备方法,电极的表面形貌和表面粗糙因子、ＲｕＯ２含量对析氢过电位的影响,电极的稳态阴极极化曲线和电化学反应动力学参数,电极在含Ｆｅ＾３＋离子的碱溶液中的稳定性。     

Fe(CN)_6~(3-)/Fe(CN)_6~)4-)与Ag/AgNO_3体系的热电化学研究

用差示测温技术测定了Ｆｅ（ＣＮ）３－６／Ｆｅ（ＣＮ）４－６体系及Ａｇ／ＡｇＮＯ３体系阳极过程的热效应，实验中采用热敏电阻测定电极表面的温度变化，利用电流、电极电位、温差和极化时间等数据，运用热电化学基本方程得出电极反应的焓变值．实验结果表明，由热电化学方法决定的焓变与由相对应的离子的热力学数据计算得来的焓变的差值为一恒定值，进一步得出２９８．１５Ｋ下标准氢电极反应的绝对熵值为８８．４Ｊ·Ｋ－１·ｍｏｌ－１．     

肌红蛋白在光透铟杂二氧化锡电极上的电化学行为

在表面活性剂溴化十六烷基三甲基铵的ｐＨ５．０的ＨＡｃ－ＮａＡｃ缓冲溶液中,在光透ＳｎＯ２电极上肌红蛋白有一灵敏的还原峰,该峰与肌红蛋白的浓度有关,该法可测至低达１０－９ｍｏｌ／Ｌ的肌红蛋白,机理研究表明,肌红蛋白有这一还原峰是肌红蛋白分子中结合氧的还原峰而不是肌红蛋白分子中Ｆｅ（Ⅲ）Ｆｅ（Ⅱ）电对的氧化还原峰     

Ag—Al2O3催化剂提高空气（氧）电极性能的量子化学研究

用ＥＨＭＯ方法优化Ａｇ－Ａｌ２Ｏ３电极催化剂的构型，计算指出Ａｇ－Ａｌ之间距离为０．２３ｎｍ时体系总能量最低，Ａｇ－Ａｌ２Ｏ３对Ｏ２有端基、侧基在桥式吸附三种方式，结果表明以端基吸附最稳定，桥式吸附次之，用吸附前后重叠集居数的变化和空成键轨道级阐明了该催化剂改善电极性能、提高电流密度的原因，此外，还讨论了电极反应机理。     

掺杂球形氢氧化镍的循环伏安特性

采用循环伏安法研究了Ｎｉ（ＯＨ）２粉末微电极，认为Ｎｉ（ＯＨ）２粉末微电极电化学过程是一个准可逆过程且电极反应在Ｎｉ（ＯＨ）２／ＮｉＯＨ之间进行；研究了阳极过程中掺杂元素对Ｎｉ（ＯＨ）２质子扩散系数的影响，发现掺Ｃｏ后比纯Ｎｉ（ＯＨ）２的扩散系数提高近１倍，而掺Ｚｎ后则扩散系数有所降低，掺Ｃｏ和Ｚｎ后Ｎｉ（ＯＨ）２电极氧的析出电位均比纯Ｎｉ（ＯＨ）２的氧的析出电位有所提高。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to