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1.
以硼酸缓冲溶液和氨水缓冲溶液的混合溶液为底液,使用示差脉冲法(DP)、方波法(SqW)和循环伏安法(CV)研究了在不同pH值条件下[Mn(CHZ)3](ClO4)2的极谱伏安行为(CHZ:碳酰肼)。实验结果表明,[Mn(CHZ)3](ClO4)2在电极表面具有吸附性,在DP和SqW方法中峰电位与pH值呈线性关系;而在CV法中峰电位则不受pH值的影响。极谱伏安法适合于该配合物的检测,并且具有灵敏度高、操作简单、快速等优点。  相似文献   

2.
本文提出了示差脉冲极谱可逆波分辨率(Ra)的定义和公式,据此可以根据半波电位和波的宽度计算出相邻两个示差脉冲极谱波的分开的程度。如果R_a=1,两波能分开,R_a=1.5,两波能较好地分开。实验结果与理论预示完全相符。  相似文献   

3.
以硼酸缓冲溶液和氨水缓冲溶液的混合溶液为底液,使用示差脉冲法(DP)、方波法(SqW)和循环伏安法(CV)研究了在不同pH值条件下[Mn(CHZ)3](ClO4)2的极谱伏安行为(CHZ:碳酰肼)。实验结果表明,[Mn(CHZ)3](ClO4)2在电极表面具有吸附性,在DP和SqW方法中峰电位与pH值呈线性关系;而在CV法中峰电位则不受pH值的影响。极谱伏安法适合于该配合物的检测,并且具有灵敏度高、操作简单、快速等优点。  相似文献   

4.
使用循环伏安法制备了聚L-谷氨酸/石墨烯修饰电极,应用扫描电镜和阻抗对修饰电极进行了表征,建立了示差脉冲伏安法测定碘的新方法。研究结果表明,在最佳实验条件下,使用示差脉冲伏安法(DPV)法测定碘,碘浓度在1.00×10-3~5.00×10-7 mol/L浓度范围内与峰电流呈现良好的线性关系,检出限为1.00×10-7 mol/L。该方法用于测定样品中的碘,结果令人满意。  相似文献   

5.
差分脉冲极谱法测定苯胺中微量硝基苯   总被引:3,自引:0,他引:3  
建立了测定苯胺中微量硝基苯的差式微分脉冲极谱法。试验发现硝基苯在-0.57V(vs.Ag/AgCl)处有一个良好的差分脉冲极谱峰。硝基苯质量浓度在1~600μg/mL的范围内,质量浓度与差分脉冲极谱峰的峰高呈线性关系。此法简便、快速、灵敏,结果准确。  相似文献   

6.
用差示脉冲极谱法对转基因植物黄耆中有效成分叶酸进行了研究,并建立了相应的检测体系.该方法简便迅速,灵敏度高,能用于中药黄耆的生理生态机理的研究.  相似文献   

7.
用差示脉冲极谱法对转基因植物黄耆中有效成分叶酸进行了研究,并建立了相应的检测体系。该方法简便迅速,灵敏度高,能用于中药黄耆的生理生态机理的研究。  相似文献   

8.
使用无失真极化转移增强技术(DEPT)可获得13_C—NMR谱中CH,CH_2和CH_3各基团子谱,应用此法测定了若干石油样品C谱线的多重性.实验表明,DEPT技术用于样品的结构分析,效果较好.运用此方法可省时、省力,并可获得很高的信噪比.  相似文献   

9.
在温度为20±0.2℃和35±0,2℃、离子强度μ(NaNO3)=0.12时,用差示脉冲极谱法研究了Cd(Ⅱ)-草酸(OX)、Cd(Ⅱ)-己二酸(HADT)二元体系及Cd(Ⅱ)-草酸(OX)-己二酸(HADT)三元体系所形成的配合物.结果表明,配合物的电极还原反应是可逆的,并受扩散控制.在Cd(Ⅱ)-草酸(OX)-已二酸三元体系中研究发现有[Cd(OX)(HADT)2]4-、[Cd(OX)2(HADT)4-、[Cd(OX)(HADT)]2-3种配合物存在.在不同温度下(20℃和35℃),测定了它们的稳定常数,并对二元体系及三元体系的部分热力学函数进行了研究和探讨.  相似文献   

10.
合成了通式为α-M_(8-m)H_m[P_2W_(16)N_(b2)O_(52)]·XH_2O(M=K,TMA,TEA,TBA)的四种盐,并通过IR、UV、极谱、XPS等测试手段对其结构和性质进行了表征,同时对样品的31P—NMR谱给予了合理的解释。  相似文献   

11.
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.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
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  相似文献   

16.
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  相似文献   

17.
18.
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.  相似文献   

19.
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).  相似文献   

20.
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.  相似文献   

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