用X射线荧光法测定黄芪中的多种矿质元素

报道了理学3070型X射线荧光光谱仪在测定宁夏黄芪样品矿质元素中的应用．采用焦化法制备黄芪样品，精密度统计结果表明，宁夏黄芪样品矿质元素的RSD(n=10)为0．2％～12％．以GBW07602，GBW07603．GBW07605国家植物标准为参考物质进行样品校准，实验结果表明，用X射线荧光法测定的结果与标准值基本相符，并用此法将宁夏黄芪与其他地区黄芪进行了比较．     

自动进样/离子色谱法测定土壤样品中的氟离子

采用自动进样／离子色谱法测定了大批土壤普查样品中F^-含量，与常规方法相比，具有操作简单方便、快速、劳动强度低、对环境无污染、适合批量样品快速测定、测定结果的精密度和准确度高等特点。5次重复测定结果的相对标准偏差为2．08％，表明精密度良好。     

微波消解/等离子发射光谱法测定中成药紫雪散中的微量元素

采用HNO3-H2O2消解体系对中成药紫雪散样品进行微波消解制样，利用ICP-AES法同时测定了样品中14种微量元素的含量，并对样品的前处理条件进行了探讨，通过添加标准回收实验，验证了分析数据的可靠性．结果表明，该方法快速、简便、数据准确可靠，结果令人满意，适合常规分析。     

傅立叶变换近红外光谱技术分析完整油菜籽含油量数学模型的建立

利用傅立叶近红外技术和大量具有代表性油菜籽样品建立含油量测定模型，内部交叉法和外部检验集样品对模型检验结果：含油量模型内部交叉验证均方差为O．755，最佳主成分维数为9，采用一阶导数＋矢量归一化方法预处理，谱区为7502．2—6098．2cm^-1、4601．6～4246．7cm^-1时，所建模型对油菜籽含油量测定结果与标准方法测定结果基本一致。说明建立的近红外分析模型能够满足油菜育种中对初级世代材料含油量的快速测定筛选要求。     

衍生化气相色谱法测定食品中的苯甲酸与苯甲酸钠

本文采用三氟化硼——甲醇法，对样品中的苯甲酸的衍生化条件进行了研究．建立了一种食品中苯甲酸和苯甲酸钠的气相色谱分析方法．经精密度、准确度实验和样品测定，均获得满意的结果．     

紫花地丁总黄酮提取的微型实验

通过对紫花地丁中总黄酮提取微型实验方法和常规实验方法的比较，微型化学实验适合选做紫花地丁总黄酮提取化学实验．用分光光度法测定含量，微型化学实验法提取紫花地丁总黄酮，测得样品中总黄酮平均含量为2．34％，平均回收率为99．7％．     

采用微波消解原子荧光光谱法测定煤中的汞

采用密闭微波方法快速消解煤、煤灰试样中的汞，并使用汞还原原子荧光光谱法进行测定．通过大量实验，比较了不同的酸体系及微波消解过程．其中煤样中汞的测定，选择体系为V2O5-HNO3-H2SO4-H2O2．灰样中汞的测定，选择体系为HNO3-HCl-HBO3．该方法能有效地将样品中的汞全部溶出，消化时间缩短至1h以内，并保证较低的分析空白,方法准确度经标准参考物质及加标回收实验验证，结果令人满意．     

二氧化硫含量测定中样品前处理方法的比较研究

考察浸泡时间及取样量对样品SO2含量的影响，结果表明，香菇、萝卜丝浸泡时间分别为8、4小时，取样量分另，1为2．00、2．00g时，样品中SO2含量最大；改进的蒸馏方法可以较好的反映样品的真实情况，其测定结果具有较好的重现性，准确度和精密度．     

偏最小二乘紫外分光光度法同时测定四环素、土霉素和甲稀土霉素

将偏最小二乘紫外分光光度法应用于合成样品中四环素（TC）、土霉素（OTC）和甲稀土霉素（MTC）三组分含量的分析研究，确定了最佳实验条件．实验结果表明，偏最小二乘紫外分光光度法对样品中各组分的平均回收率在95．8％-103．6％之间，样品不经分离即可同时测定，取得了满意的分析结果．     

萃取富集原子吸收法测定烘焙食品中痕量铅

烘焙食品试样经灰化处理后，用APDC-DDTC-IBK体系萃取富集试液中的铅，利用空气-乙炔火焰原子吸收法测定烘焙食品样品中铅的含量．考察了仪器的工作参数、试液的酸度、反应时间和萃取时间等测定条件，并对可能存在的元素进行了干扰实验．在最佳条件下本法测定铅的相对标准偏差为1．5％-2．6％，回收率为98．2％-102．1％．     

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