高半胱氨酸SAM膜电极的制备及其电化学行为研究

研究了高半胱氨酸在金电极上形成单分子自组装膜的条件，并利用循环伏安法，交流阻抗谱研究了[Fe(CN)6]^3-/4-在高半胱氨酸SAM膜电极上于不同pH值溶液中的电化学行为。循环伏安结果表明，在pH大于高半胱氨酸等电点的溶液中，[Fe(CN)6]^3-/4-在膜电极上的循环伏安曲线峰电流明显降低，峰分离差增大，说明随pH值的增加，[Fe(CN)6]^3-/4-离子对在SAM膜电极上的可逆性变差；交流阻抗图谱显示，由于SAM膜电极表面带负电荷时，[Fe(CN)6]^3-/4-难以靠近电极表面，使其与电极表面的电子交换反应变得困难，在SAM膜电极上的电化学反应电阻Rct明显增加，并且随电解质溶液的pH增加而增加。     

电子传输过程对硫醇自组装单层膜结构的影响

应用交流阻抗技术及循环伏安技术研究了十八硫醇修饰的金电极在Fe(CN)63-/4-溶液中的电化学行为,提出电化学氧化还原过程中的电子传输可以诱导十八烷基硫醇自组装单分子层膜结构的一定重组,使其变得更加均一有序.     

含咪唑烷基硫醇自组装膜界面铜离子配位研究

合成了6-(咪唑-2-基)-1-己硫醇(IHT),在金电极表面形成纯的自组装膜及其与1-己硫醇(HT)的混合自组装膜,并将这些自组装膜在溶液中与铜离子进行界面配位.应用电化学循环伏安法和交流阻抗谱法探讨了各种自组装膜修饰电极界面配位铜离子的电化学行为.实验结果表明,IHT与HT以1∶4比例进行界面组装得到的混合自组装单分子层最致密,自组装膜的铜离子界面配位浓度最高达到2.3×10-11mol/cm2.界面形成的IHT-Cu2+配合物在不同的pH值溶液中测量结果表明该配合物在pH 6.4时是可以稳定存在的.     

12硫醇修饰金电极K_3Fe(CN)_6/K_4Fe(CN)_6体系的电化学参数

采用自组装(SA)技术制备了正十二硫醇的SA 单分子层膜.应用电化学交流阻抗及循环伏安技术研究了12 硫醇SA 单分子层膜在K3Fe(CN)6/K4Fe(CN)6 溶液中的电化学行为.测得了表观电子传递系数α+ β≠1,电子隧穿系数为(0.83～1.11)/CH2.     

噻吩羧酸在金表面的自组装膜及其电化学性质

研究了具有平面环状共轭体系的硫杂环化合物噻吩羧酸在金表面的自组装单分子膜及其修饰金电极的电化学行为．以Fe(CN)6^4-/3-为“探针”离子，用循环伏安法对自组装膜的形成、电极界面电容及其组装机理进行了研究．结果是噻吩羧酸在Au上的覆盖度约为95％，金电极的界面微分充电电容由修饰前的0．294μF／cm^2下降到0．167μF／cm^2，由此可见噻吩羧酸在金表面形成了致密的单分子膜．     

对羟基苯硫酚自组装膜修饰金电极的制备及电化学表征

在金电极表面制备了对羟基苯硫酚(4-HTP)自组装单分子膜,构建了一种羟基化金电极表面.在优化实验条件下,利用交流阻抗技术对4-HTP自组装单分子膜电极(4-HTP SAM/Au)进行了原位表征,采用Randles等效电路对阻抗复平面图进行模拟,确定该电极体系的等效电路以及电化学参数,通过电荷传递电阻Rct与组装时间的关系,给出了4-HTP SAM在金电极表面的组装动力学曲线.结果表明,电子传递电阻(Rct)随自组装时间的延长而迅速减小,证明4-HTP SAM是一种导电膜,当自组装时间达到120 min后,Rct不再变化,4-HTP SAM达到组装平衡状态.研究结果对SAMs的制备具有一定指导意义,在生物传感器的研究中具有应用前景.     

Au/CaM自组装膜方波伏安法表征

采用方波伏安法,在包含1 mmol/L[Fe(CN)6]3-/[Fe(CN)6]4-的0.15 mol/L的NaCl溶液中,对Au/CaM膜的电化学行为进行了初步表征。由方波伏安电流响应图可知:CaM可以在Au基底自组装成膜,[Fe(CN)6]3-/[Fe(CN)6]4-在Au/CaM膜电极上发生的是电化学不可逆反应过程。     

DNAzyme在金电极上自组装电化学生物传感器的制备

利用巯基与金表面Au-S键的自组装技术,可以将巯基修饰的DNAzyme固定在金电极表面形成电化学生物传感器,并以含有[Fe(CN)6]3-/4-的磷酸缓冲液(PBS)作为电化学检测底液,利用循环伏安法初步研究该修饰电极的电化学行为和修饰过程的电化学表征.DNAzymes自组装膜的存在明显抑制了二茂铁与[Fe(CN)6]3-/4-之间的电子转移.结果表明,基于巯基修饰的DNAzyme在金电极表面能够发生自组装作用,在金电极表面形成较为稳固的自组装DNAzyme膜.     

pH对半胱胺自组装膜在Fe(CN)63-/4- 溶液中的循环伏安的影响

以Fe（CN）6^3-/4-作为探针离子，用循环优安（CV）方法，对半胱胺自组装膜进行研究；通过改变溶液的pH，研究溶液中H^＋浓度对半胱胺自组装膜在Fe（CN）6^3-/4-溶液中电化学行为的影响；利用电流滴定的方法得出半胱胺自组装膜的表面解离常数（表面pKb）．     

超氧化物歧化酶模型化合物在金电极上的分子A组装

采用3-巯基丙酸在金电极上自组装得到自组装单分子层(SAM)，再利用DCC作酰胺键偶合剂，将超氧化物歧化酶(SOD)模型化合物Fe(IDB)CI3(简称Fe-MSOD，IDB为N，N-二(2’-苯并咪唑甲基)亚胺)共价键合到自组装在金电极表面的3-巯基丙酸单分子层上，构筑了一种超氧化物歧化酶模型化合物分子组装体系膜修饰电极(Fe-MSOD／3-MPA／Au)．采用电化学循环伏安法、交流阻抗法对该修饰电极进行了表征．初步探讨了此修饰电极的电化学氧化还原性质．     

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…     

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。     

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.