ICP-MS法测定隐伏矿床植物中的多种微量元素

采用HNO3-H2O2处理样品,Rh作为内标进行基体效应补偿,通过电感耦合等离子体质谱(ICP-MS)法,测定隐伏矿床植物样品中的Ti、Co、Ni、Cu、Zn、Mo、Cd、W、Pb共9种微量元素的含量。结果建立的方法的各元素检出限为0.01～0.50 ng.ml-1,样品分析结果的相对标准偏差为1.32%～6.32%,加标回收率为91.7%～103.5%。建立的方法简便、快速、准确,适用于隐伏矿床植物中微量元素的测定。     

微波消解ICP-AES法测定柴胡中微量元素

微波溶样技术具有简便快速、节约试剂、污染少和样品溶解完全等特点,适用于植物中多种元素的测定.采用HNO3-HClO4作消解荆进行微波溶样,美国利曼公司生产的PS-Ⅰ型中阶梯光栅光谱仪测定柴胡中的微量元素,结果显示,其相对标准偏差为1.81%～6.76%,回收率为93%～103%.该结果为建立高效、准确和同时测定多种微量元素的柴胡质量检测标准方法提供了有利数据.     

湿法消解火焰原子吸收光谱法测定盆栽看椒果中微量元素

用HNO3-H2O2对样品进行消解，采用火焰原子吸收光谱法测定盆栽看椒中6种微量元素K、Ca、Fe、Zn、Cu、Mn.结果表明，在优化的实验工作条件下，对样品中6种微量元素可进行分别测定，互不干扰，方法回收率为87.0%~103.3%.     

微波消解-ICP-MS法测定土壤、沉积物中多元素

考察了微波消解-电感耦合等离子体质谱（ICP-MS）法同时测定土壤、沉积物等样品中的12种元素的方法.结果表明，由3 mL HNO3-1 ml HCl-1 mL HF组成的混合酸对土壤、沉积物具有较好的消解能力.5种标准物质的测定结果表明，该方法快速简便、准确度高、精密度好是一种土壤、沉积物样品中多元素同时测定的广普方法.各元素的检出限为0.01-3.64 ng·g^-1RSD〈3.64%.     

膏霜类化妆品的预处理及多种微量元素的测定

用HNO3 H2 SO4 HClO4消化法、HNO3 H2 SO4消化法、(HNO3 HClO4)混合酸 H2 SO4消化法三种预处理方法处理膏霜类化妆品样品 ,并以ICP AES法直接测定样品中铜、铬、镉、锰、锌、铅的含量 .结果显示 ,采用 (HNO3 HClO4)混合酸 H2 SO4消化法预处理样品 ,能够得到较好的效果 ,测定方法加标回收率为 93 6 % - 1 0 3 8% ,1 0次测定的RSD (n =1 0 )小于4 89% ,方法操作方便 ,分析速度快 ,结果准确     

火焰原子吸收光谱法测定马齿苋中的微量元素

采用火焰原子吸收光谱法,用浓硝酸和过氧化氢消解样品,再采用标准曲线法测定了马齿菜中Cu、Fe、Mn、Zn四种微量元素.在优化的仪器工作条件下,可分别测定马齿菜中的四种微量元素,不相互干扰,此法的回收率在96.4%~104%之间.该方法操作简单、准确度较高,测定结果令人满意.     

预处理方法对植物生物质中钾元素含量测定的影响

采用干灰化法、湿式消解法和微波消解法对稻壳生物质进行了预处理,通过火焰原子吸收光谱法(FAAS)对不同预处理方法得到稻壳处理液中的钾元素含量进行了测定,为避免钾原子电离干扰的影响,加入了消电离剂.结果表明:加入500,μg/mL CsCl溶液可基本消除K+溶液测量过程中钾原子的电离干扰;稻壳样品经HNO3干灰化法、HNO3–H2O2湿式消解法和HNO3–H2O2微波消解法处理后,测定的稻壳中钾元素含量分别为0.638,4%、0.760,4%和0.778,6%;湿式消解法的实验结果重现性好,相对标准偏差仅为0.17%,且分析仪器简单,综合考虑,湿式消解法的效果优于干灰化法和微波消解法.     

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。     

ICP—AES法测定金鸡片中的常量和微量元素

建立用电感耦合等离子发射光谱(ICP-AES)法同时测定金鸡片中Mg、Ca、Mn、Fe、Cu、Zn、B、P、Sr含量的分析方法。采用V(浓硝酸)+V(高氯酸)=(6+2)mL混合酸溶解消化样品,在选定的实验条件下直接测定。结果表明,九种元素的回收率(n=6)在94.5%～105.5%之间,RSD≤6.7%。此方法简便、快速、可靠,用于金鸡片中常量和微量元素的测定,结果满意。     

原生态金秋梨中微量元素锌的光谱测定

测定黔东南苗族侗族自治州原生态"苗疆"牌台江金秋梨中微量元素锌的含量。方法:用正交试验优化仪器最佳工作条件,微波消解样品,火焰原子吸收光谱法(FAAS)测定微量元素锌。结果:"苗疆"牌金秋梨锌元素含量为3.1mg/Kg,方法的特征浓度为0.0057μg/mL,检出限为0.0079μg/mL,相对标准偏差为0.62%,加标回收率在98%~102.7%之间,适用于金秋梨中微量元素锌的测定。结论:"苗疆"牌金秋梨微量元素锌的含量较高,具有很高的食用价值和药用价值。     

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.     

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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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.     

英文诗歌中的喻类修辞

为了有助于提高英文爱好者的个人情操、文化素养和学习兴趣,以及专业人员对英语学习和研究进行多途径的探索,本文通过一些精选诗歌的引证和分析,着重论述了喻类修辞法在英文诗歌中的运用其及效果。     

Man Is Unable to Change the Miserable Life——Analysis of the Arrangement of Four Characters in The Glass Menagerie

Tennessee Williams is considered as one of the most important American playwrights since World War II.The Glass Menagerie is his first successful drama,which describes a tragic situation of family and means to say that Man is unable to change the miserable life,no matter whatever means he try,This essay focuses on the analysis of the arrangement of the four main characters:Laura.Amanda,Jim and Tom to reveal the theme.Laura is fragile.Amanda is brave.Jim is vital.Tom is sensible.And all of them develop and try the different means to struggle against life,but fail tragically.With the evidence,the paper comes to conclusion naturally that Man is unable to change the miserable life,and he dooms to fail.     

Characterization of root-nodulating bacteria on Retama raetam in arid Tunisian soils

The aim of this study is to investigate the diversity of Retama raetam root-nodule bacteria isolated from arid regions of Tunisia. Twelve isolates, chosen as representative for different 16S rRNA gene patterns, were characterized by 16S rRNA gene sequencing and phenotypic analysis. Isolates were assigned to Sinorhizobium, Rhizobium and Agrobacterium. Symbiotic properties of Sinorhizobium and Rhizobium isolates showed a large diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Strain RK 22 identified as Rhizobium was the most effective isolate.     

An Affordable Accurate Evaluation of the Binding Conformations Predicted by Molecular Docking Studies in Bio-System

正Recently,docking has been widely used to predict the binding-modes of protein-inhibitors,when the crystal complexes structure was absent.Most docking algorithms are able to generate a large number of probable conformations,it,however,is difficult to effectively evaluate these docking poses and identify the most reasonable bindingmode.In the present study,on the basis of the crystallographic data of human 3-hydroxy-3-methylglutaryl coenzyme     

WIMAX与WI-FI技术分析及联合组网

介绍了WiMAX与Wi-Fi两种无线宽带接入技术,并对两者之间的关系及相互之间的影响做了对比及分析,并对WiMAX的关键技术进行了详细说明,最后对两者的联合组网方式做了简单的探讨。