离子色谱在水质分析中的应用

文章采用离子色谱法, Shim - PackICAl 阴离子柱,以2. 5mmol/L 邻苯二甲酸 2 4mmol/L三(羟甲基)氨基甲烷为流动相,同时测定饮用水中氯化物、硝酸盐氮和硫酸盐的含量。该法回收率为99%~102%,相对标准偏差均<3%,最低检测限分别为0 010mg/L、0 005mg/L、0.020mg/L。实验证明该方法快速、简便、准确、灵敏度高。     

一株耐盐耐碱J101球菌的抗性研究

从安徽芜湖冶炼厂污染土壤中分离出数百菌株,对其中一株菌J101进行了耐盐耐碱性能、重金属、抗生素抗性研究.J101菌株为一球菌,经初步生理生化鉴定为葡萄球菌属(Staphylococcus sp.),能够在液体细菌培养基中耐NaCl高达20%、耐碱高达pH10;在含6mmol/L Cd2 ,30mmol/L Pb2 、4mmol/L Zn2 、2mmol/L Cu2 、6mmol/L Ni2 、16mmol/L Mn2 和4mmol/L Cr6 细菌琼脂培养基上能够生长.J101菌株能够抗多种抗生素,可生长在Amp 400mg/L, Kan 30mg/L, Str 80mg/L, Rif 100mg/L琼脂培养基上.阳离子Zn2 存在时进入菌体中的Cd2 明显减少,活菌体J101能够吸附83.73% Cd2 .     

生菜(Lactuca sativa var ro mana Hort.)下胚轴愈伤组织的诱导与植株再生

通过对生菜下胚轴的愈伤诱导和植株再生的研究 ,发现诱导愈伤组织时 ,MS培养基中加 0 .5mg/L　 6 BA 1mg/L　 2 ,4 D 0 .1mg/LNAA效果最好 ,其出愈率达 94 %;愈伤组织分化为芽时 ,在MS 1.0mg/L　 6 BA 0 .0 5mg/L　NAA中分化频率最高 ,达 10 0 %.再生苗可在 1/ 2MS 0 .5mg/L　NAA中诱导生根成完整植株 .     

痕量手性药物扑尔敏的在线富集和拆分

建立了低浓度下药物扑尔敏的在线富集和拆分方法 ,并分别考察了不同的拆分试剂对扑尔敏的拆分效果的影响 ,十六烷基磺酸钠 (SDS)浓度对富集以及拆分效果的影响和进样时间对检测限的影响 .实验结果表明扑尔敏的最佳富集拆分条件为 5 0mmol/LSDS +5 0mmol/L手性拆分剂 β -CD +10 0mmol/L脱氧胆酸钠 (SDC) +30mmol/LNa2 B4 O7.当进样时间为 4 0 0s时 ,扑尔敏的检测限降低到 4 .1mg/L .     

葶苈子植物愈伤组织诱导及植株再生的研究

对葶苈子植物 :葶苈 (Drabanemorosa)、印度菜 (Rorippaindica)及北美独行菜(Lepidiumvirginicum)愈伤组织的诱导、分化、再生苗的生根进行了研究。结果表明 :(1)在基本培养基为MS ,附加 6 -BA 0 .5mg/L +NAA0 .5mg/L的培养基上三种植物均能产生愈伤组织 ,其出愈率达 10 0 % ,而且 2 0 %的外植体具有一次成苗的能力 ;(2 )在愈伤组织的分化中 ,6 -BA1mg/L +NAA 1mg/L的激素组合是最佳的 ,其分化率为 10 0 % ;(3)无根苗生根的培养基为MS + 0 .5mg/LNAA ,生根率为 90 %     

钴卟啉和Nafion膜的葡萄糖电极的设计与优化

目的 :研制一种基于钴卟啉和Nafion的葡萄糖电极 .方法 :用序贯淘汰水平法对该电极膜组成进行优化 .结果 :其优化后电极的最佳膜组成为 :1.0mmol/L钴卟啉 [5 ,10 ,15 ,2 0 -tetrakis (4-methoxy -phenyl) - 2 1H ,2 3H -porphinecobalt](TMPPCo)溶液为 15 μL、10mg·mL- 1葡萄糖氧化酶(GOD)为 15 μL ,Nafion溶液为 6 0 μL .该电极用于测量葡萄糖时的线性范围为 :0～ 4mmol/L ,检测下限为 0 .4 μmol/L .结论 :该电极具有响应快速、灵敏、重现性好、寿命较长的特点 .     

谷氨酸、褪黑素导致海马脑薄片诱发群体峰电位的变化过程研究

在大鼠海马脑薄片上电刺激海马Schaffer侧支纤维 ,胞外记录CA1区锥体细胞层诱发群体峰电位 (PopulationSpike ,PS) ,观察灌流谷氨酸 (Glu)和褪黑素 (MEL) 40min ,人工脑脊液冲洗30min对PS的影响 ,结果显示 :不同浓度 ( 1 .0、1 .2 5、2 .5和 5.0mmol/L)的Glu作用下 ,70min末PS值百分比分别为 1 560 .5%、1 50 .7%、1 3.1 %、4.1 % ;并且Glu浓度高时 ( 2 .5或 5.0mmol/L) ,恢复期末增加刺激强度均不能使PS值升高 .不同浓度MEL( 0 .4μmol/L、0 .5μmol/L、0 .6μmol/L、0 .7μmol/L)作用下PS值在 70min内波动幅度随浓度升高而变小 ,70min末PS值百分比分别为1 93.8%、1 2 9%、75.2 % (恢复期末增大刺激强度 ,则可恢复到 1 0 0 % )、97.1 % .上述结果提示 :低浓度Glu( 1mmol/L ,1 .2 5mmol/L)对神经元具有兴奋作用 ;高浓度Glu( 2 .5mmol/L ,5mmol/L)具有神经毒性作用 ;MEL对神经元具有兴奋和抑制双重作用 ,因MEL浓度不同 ,其作用形式会有不同     

离子色谱法测定食品中二氧化硫残留量

建立二氧化硫残留量测定仪-离子色谱法测定食品中二氧化硫的分析方法。样品加入 10 mL 盐酸（1∶1）后,使用二氧化硫残留测定仪进行蒸馏,蒸馏液中二氧化硫被 20 mL 过氧化氢 （2%）溶液吸收氧化为硫酸根,通过离子色谱仪对馏出液中硫酸根含量进行测定,以保留时间定性, 峰面积定量,经计算转化为样品中二氧化硫的含量。结果表明：离子色谱KOH淋洗液洗脱梯度条 件为10 mmol/L 18 min、40 mmol/L 5 min、10 mmol/L 5 min时,硫酸根标准溶液的浓度在0～5.0 mg/L 范围内呈良好的线性关系（R2 = 0.999 6）,检出限（S /N = 3）为0.012 mg/kg,样品加标回收率范围为 97.6～102.3%。本方法操作简便快速,准确度、精密度好,适用于不同类型食品中二氧化硫的测定。     

絮凝沉降-Fenton氧化-吸附法处理采油污水实验研究

我国油田的采油污水绝大部分经处理后用于油田注水 ,但由于种种原因 ,还有一部分采油污水不能回注 .这部分水外排至环境中 ,对环境产生一定的影响 .本文以甘谷驿油矿采油污水为研究对象 ,采用絮凝沉降 -Fenton氧化 -吸附法对该采油污水进行外排处理实验研究 .考察了 pH值、H2 O2 投加量、Fe2 +投加量、氧化时间、吸附时间、活性炭加量对COD去除率的影响 .实验结果表明 ,最佳处理条件为絮凝剂选用聚合硫酸铁 ,沉降 30min ;pH为 3.0～ 4 .0 ,30 %双氧水加量为 8mL/L ,m (Fe2 +)∶m (H2 O)为 4 % ,氧化时间 12 0min ;活性炭加量 4 .0～ 5 .0 g/L ,吸附时间 12 0min .在这种处理条件下 ,可使污水含油量从 93.1mg/L降至 5mg/L以下 ,悬浮物含量从 172mg/L降至 10mg/L以下 ,CODCr值从 2 6 34mg/L降至 10 0mg/L以下 ,达到国家一级排放标准     

Cu~(2 )、Zn~(2 )、Cd~(2 )对丰年虫和对虾无节幼体趋光反应的影响

研究了几种常见重金属 (Cu2 、Zn2 、Cd2 )对丰年虫、长毛对虾、斑节对虾无节幼体趋光反应的影响 .结果发现 :1) Zn2 、Cu2 、Cd2 对丰年虫无节幼体的 2 4 h半数致死浓度分别为 310 .36、34 .61和 2 0 1.8mg/ L.而 Cu2 、Zn2 浓度分别为 2 .0 7、19.86mg/ L时 ,幼体的等效趋光值即降到对照组的 5 0 % .2 ) Cu2 、Cd2 对长毛对虾无节幼体的半数致死浓度分别为 0 .0 31、0 .180 mg/ L.而 Cu2 浓度为 0 .0 0 3mg/ L、Cd2 浓度为 0 .0 0 4 mg/ L时 ,即使幼体的等效趋光值降为对照组的 5 0 % .3)Zn2 、Cu2 对斑节对虾无节幼体的半数致死浓度分别为 0 .5 0 6、0 .0 2 6mg/ L.而当 Zn2 、Cu2 的浓度分别为 0 .0 0 7和 0 .0 0 2时幼体的等效趋光值即降为对照组的 5 0 % .     

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.     

Features of Women''s language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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