铬黑T还原法测定铬酸根

本文利用CrO_4~(2-)在0.1～0.2mol/L HCl溶液中氧化铬黑T,用缓冲溶液(NH_3-NH_4Cl)将溶液调到pH≈9.6后,在615nm下测定吸光度的减少,建立了测定Cr(Ⅵ)的新方法.方法的定量检出限为6μg/25ml,CrO_4~(2-)线性范围为0～24和24～48μg/25ml CrO_4~(2-).同时试验了35种共存离子的干扰,对金属离子的干扰消除,可用DDTC CHCl_3萃取分离和加柠檬酸,酒石酸钠掩蔽.此方法用于废水中CrO_4~(2-)的测定,得到满意的结果.     

氟离子选择电极法测啤酒中的氟

本文采用氟离子电极法测定啤酒中的氟 ,测量溶液的酸度为PH5— 6,用总离子强度调节缓冲液 ,消除干扰离子及酸度的影响 ,方法回收率 96.1 2 %～ 99.2 4 % ,线性范围为 1 0 - 1 mol/L～ 5× 1 0 - 7mol/L ,最低检出浓度 0 .0 1 μg/ml,本法操作简单、快速 ,适合作常规测定 .     

硫酸预活化测定痕量氟的离子选择性电极法

研究了一种在0.5 mol/L的硫酸介质中先活化氟离子选择性电极,然后再在含有硫酸总离子强度调节混合溶液(TISAM)介质中测定痕量氟的方法.该方法线性范围为1.00×10-2~1.00×10-7mol/L,检出限为1.9μg/L,应用到绿茶饮料、水、牛奶中痕量氟的测定,结果令人满意.     

用分光光度法测定痕量铜、锌离子

研究了用PAN螯合剂负载的聚氨酯泡沫塑料富集铜、锌离子,用分光光度法测定其痕量的简单易行方法。12吡啶偶氮1萘酚(PAN)在pH9.0缓冲液中既做为负载剂又做为显色剂。铜、锌离子富集之后用1 mol/L硝酸洗脱,用光度法测定。铜、锌离子均在0～12μg/10ml范围符合比尔定律。最大吸收波长为555nm,摩尔吸光系数5.36×10~4L·mol~(-1)·cm~(-1)。本法可用于天然水和麦饭石水中铜、锌离子含量的测定。     

石墨烯/离子液体/壳聚糖/血红蛋白修饰玻碳电极检测过氧化氢

将石墨烯、离子液体(1-丁基-3-甲基-咪唑四氟硼酸盐)与壳聚糖结合,制备了一种新型的石墨烯-离子液体/壳聚糖纳米复合膜修饰玻碳电极.用循环伏安法研究了血红蛋白在该修饰电极上的直接电化学行为.结果表明,血红蛋白在该纳米复合膜电极上对过氧化氢具有良好的催化性能.过氧化氢的电流响应信号与其浓度在0.1～500μmol/L范围内呈线性关系,检出限为0.02μmol/L(RSN=3),为过氧化氢检测提供了一种灵敏的新方法.     

铟—PAR络合吸附波的极谱行为研究

本文介绍了在0.09mol/L NH_3·H_20—0.21mol/L NH_4Cl介质中,当有8×10~(-5)mlo/L PAR存在时,In~(3+)在—0.85V(vs.S·C·E·)处产生一灵敏的络合吸附波,其线性范围为0.1～0.8μg/ml。对这一络合吸附波的性质进行了研究,并测定了该络合物的组成。利用In—PAR络合吸附的极谱行为进行了纯铅中微量铟的加入回收实验,测定了合成样品中的微量铟。     

铋粉修饰碳糊电极循环伏安法测定EDTA的研究

制备了铋粉修饰碳糊电极,实验发现,用此电极为工作电极时,在0.1mol/L盐酸溶液中,于0.0 V(vs.SCE)处富集2min,阴极化扫描,于-0.8V左右获得一灵敏的不可逆还原峰.详细研究了测定EDTA的测定条件,如介质的选择,富集电位,富集时间,扫描速度和修饰剂用量等.在选定的优化实验条件下,峰电流与溶液的浓度在4.00×10-4～2.00×10-3mol/L范围内呈良好的线性关系,其线性回归方程为ip=1.89×10-4～0.0521CEDTA(mol/L), 相关系数为: r=0.9963,检出限为1.30×10-4mol/L.     

匀浆法提取-离子色谱法测定卷烟纸中钾、钠、钙、镁

研究了用离子色谱法同时测定卷烟纸中钾、钠、钙、镁.卷烟纸用1%的盐酸溶液匀浆法提取,然后以Ionpac CS16(5mm×250mm,5μm)离子交换柱为固定相,0.03mol/L甲烷磺酸为流动相分离,电导检测器检测测定,方法的检出限为1.8～6.5μg·L-1,加标回收率为94%～104%,相对标准偏差为0.84%～1.2%,结果满意.     

硝酸消化直接测定蔬菜中微量氟的离子选择性电极法

研究了用硝酸消化处理蔬菜样品,直接在含硝酸的总离子强度调节混合液(TISAM)中测定氟的离子选择性电极法.该方法线性范围为1.00×10-6～1.00×10-2mol/L,检出限为13.5μg/L,操作简便、快捷,测定结果比较满意.     

HPLC法测定血浆及尿液中阿普唑仑浓度

采用Agilent Eclipse XDB-C18色谱柱(4.6mm×150mm,5μm),以甲醇-水(60¨40)为流动相,流速1.0ml/min,检测波长254nm,建立高效液相法(HPLC)测定血浆及尿液中阿普唑仑浓度。结果表明,HPLC法测定阿普唑仑和内标物的出峰时间是5.1min和8.73min,分离效果较好;阿普唑仑质控3种浓度(4.0μg/ml,8.0μg/ml,16.0μg/ml)日内和日间的RSD,血浆样品均小于6%,尿样均小于7%,血浆回收率为91.15%～93.69%,尿回收率为86.79%～90.11%,血浆及尿样品线性范围为2.0～64.0μg/ml,相关系数为0.9907。血浆和尿样品中阿普唑仑的最低检出限为2.0μg/ml。此条件可以对中毒药物阿普唑仑进行快速检测并定量,方法简便,准确。     

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