催化氧化法处理对氯硝基苯(PCNB)废水的研究

以活性炭为催化剂，H2O2作氧化剂催化氧化降解对氯硝基苯(PCNB)，结果表明，在H2O2／CODcr=1．2，活性炭／H2O2=0．4，pH=3．0的条件下，反应可在180min结束，PCNB的去除率高于99％，CODcr去除率可达80％，与Fenton试剂法相比较，CODcr去除率提高1．78倍，并对降解机理作了初步讨论。     

气相色谱法测定黄芪甘草中有机氯农药残留量

[目的]建立黄芪甘草中分析有机氯农药六六六（BHC）,滴滴涕（DDT）,五氯硝基苯（PCNB）残留量的一种毛细柱气相色谱的分析方法．[方法]样品以丙酮提取,在氯化钠存在下,以二氯甲烷进行液液分配,用浓硫酸磺化,采用弹性石英毛细管柱Rtx-225（30m＊0．32mm＊0．10um）及电子捕获检测器（ECD）,外标法计算含量．[结果]加样回收率在90．43%-104．58％,RSD％为0．05％-4．28％样品中检出的有机氯农药残留量总六六六（BHC）小于200ng／g,总滴滴涕（DDT）小于200ng／g,五氯硝基苯（PCNB）小于100ng／g,均符合国家标准．[结论]该法适用于测定黄芪甘草中的有机氯农药残留量．     

丹参片等四种中成药中有机氯农药残留量分析

用毛细管气相色谱法一次分析丹参片等四种中成药中六六六(α、β、γ、δ—BHC)、DDT(P，P’-DDE、P，P’-DDD、O，P’-DDT、P，P’-DDT)、五氯硝基苯(PCNB)和艾氏剂(Aldrin)，方法灵敏度高，最低检测浓度为1．0～3．8ng／g，精密度1．70％—6．89％(RSD)，加样回收率82．9％～98．6％，实验结果表明，四种中成药的有机氯农药残留量较低，均符合我国对植物药和制剂的进出口行业标准。     

邻氯硝基苯降解菌Pseudomonas putida OCNB-1的分离、鉴定与降解质粒研究

摘要：以邻氯硝基苯为唯一碳源、氮源和能源从某化工厂废水处理站分离出一株细菌, 经微生物自动测定仪WSVTK-R07.02和16SrRNA扩增测序鉴定为Pseudomonas putida;在 培养基pH为8.0,培养温度32 ℃,摇床转速120 rpm 条件下考察了该菌株降解邻氯硝基苯的能力, 菌株42 h内将起始浓度为1.07 mM的对邻氯硝基苯降解近80%;经质粒检测,在菌株OCNB-1中发现一条质粒条带,选用7种内切酶对质粒pOCNB-1进行单酶切,得出质粒大小约为32 Kb;抗生素抗性实验表明菌株对红霉素、氨苄青霉素、青霉素钠的抗性与质粒无关,对利福平、氯霉素的抗性与质粒有关;通过细菌接合,质粒转移到无降解邻氯硝基苯能力的Pseudomonas.stutzeri受体菌中,接合子Pseudomonas.stutzeri能利用邻氯硝基苯为唯一碳源、氮源和能源,证明质粒为降解质粒。     

RuCl3/TPPTS催化CO选择还原间氯硝基苯反应

将水溶性膦／钌配合物用于以CO为还原剂的水／有机两相间氯硝基苯选择还原为间氯苯胺的反应．考察了十六烷基三甲基溴化铵(CTAB)与氢氧化钠(NaOH)浓度、反应温度、CO压力以及膦／钌比例等因素对反应结果的影响．研究结果表明，当反应条件为135℃、CO压力3MPa、NaOH浓度2mol／L时，反应8h，问氯硝基苯的转化率为97％，间氨苯胺的选择性可达到99％以上．通过简单的相分离操作就能将水相中的催化剂循环使用，循环使用3次后，间氯硝基苯的转化率和间氨苯胺的收率仍可达到89％以上．     

邻氯硝基苯降解菌OCNB-1的分离鉴定与降解质粒

以邻氯硝基苯为唯一碳源、氮源和能源,从某化工厂废水处理站活性污泥中分离出一株细菌OCNB-1, 经微生物自动测定仪WSVTK-R07.02和16S rDNA扩增测序初步鉴定为Pseudomonas putida;在培养基pH值为8.0、培养温度为32 ℃、摇床转速为120 r/min的条件下,考察了该菌株降解邻氯硝基苯的能力,发现菌株42 h内将起始浓度为1.07 mmol/L的该化合物降解了约80%;经质粒检测,在OCNB-1菌株中发现一条质粒条带,选用7种内切酶对质粒pOCNB-1进行单酶切,得出质粒大小约为32 kbp;抗生素抗性实验表明菌株对红霉素、氨苄青霉素、青霉素钠的抗性与质粒无关,对利福平、氯霉素的抗性与质粒有关;通过细菌接合,质粒转移到无降解邻氯硝基苯能力的Pseudomonas.stutzeri受体菌中,接合子Pseudomonas.stutzeri能利用邻氯硝基苯为唯一碳源、氮源和能源,证明质粒为降解质粒.     

水溶性钌络合物催化卤代芳香硝基化合物选择性加氢的研究

研究了水／有机两相催化体系中，水溶性钌络合物催化剂AC—1催化卤代芳香硝基化合物中硝基的选择性加氢反应．以对—氯硝基苯为底物，考察了表面活性剂种类及浓度、反应温度、氢压、催化剂浓度和反应时间等对反应转化率和选择性的影响．实验结果表明，阳离子表面活性剂对反应有明显的影响，其中以添加十六烷基三甲基溴化铵(CTAB)效果最好．当反应条件为90℃，氢压4．0MPa时，反应5h，对-氯硝基苯转化率可达100％，生成对—氯苯胺的选择性可达99．9％．该催化体系对其它卤代芳香硝基化合物的选择性加氢也具有很高的活性和选择性。     

对硝基苯磺酰基乙酸酯类化合物与α-氯丙酸酯的反应

在固—液相转移催化（Ｋ２ＣＯ３／ＣＨ３ＣＮ／ＴＥＢＡ）条件下，对硝基苯磺酰基乙酸酯类化合物与α－氯丙酸酯在６０～８０℃反应没有生成正常的烷基化产物，而得到了２－（４－硝基苯磺酰基）丙酸酯，产率３０％～７０％．反应机理可能是：对硝基苯磺酰基乙酸酯与α－氯丙酸酯反应时相继发生了烷基化和消除反应，消除反应生成的对硝基苯亚磺酸钾与α－氯丙酸酯反应而得到最终产物．     

不同温度下红球菌降解氯代苯甲酸及共代谢作用

自某农药厂污水处理系统的活性污泥中分离纯化一株高效降解3-氯代苯甲酸的菌株S-7，形态学、生理生化特性及16S rRNA基因序列的结果表明S-7为红平红球菌（Rhodococcus erythropolis）．研究了在不同温度条件下，R．erythropolis S-7对3-氟代苯甲酸的降解能力．实验表明该菌在20℃和30℃时，于60h内将底物全部分解．并且分析了该菌在30℃时的反应动力学．在10℃的低温条件下，能以3-氯代苯甲酸为唯一碳源和能源生长，并在5d内完全降解底物．该菌的耐冷性能对于低温地区生物修复有重要意义，在低温地域有广泛的应用前景．研究了在以葡萄糖为生长基质的条件下，菌株S-7对2-氯代苯甲酸和4-氟代苯甲酸的降解能力．S-7可共代谢2-氯代苯甲酸．但是不能共代谢降解4-氯代苯甲酸，质粒提取实验表明．降解3-氯代苯甲酸的基因位于染色体上．     

黔产5种中药材有机氯农药残留安全限量研究

目的:对5种黔产中药材中总六六六(α-BHC、β-BHC、γ-BHC、δ-BHC)、总滴滴涕(p,p'-DDE、p,p'-DDD、o,p'-DDT、p,p'-DDT)和五氯硝基苯(PCNB)的9种有机氯农药残留量进行测定,为控制中药材安全限量提供实验数据,为开发利用药材资源提供安全性保障。方法:样品经丙酮,二氯甲烷与石油醚混合有机溶剂超声提取,选用气相色谱-电子捕获检测(GC-ECD) Rtx-1701弹性石英毛细管柱(0. 25 mm×30 mm×0. 25μm),以不分流方式进样,进样口温度230℃,检测器温度300℃;程序升温,初始温度100℃,先以10℃/min升至220℃,再以8℃/min升至250℃保持10 min,外标法计算含量,应用SPSS 22. 0软件对数据结果进行统计学分析。结果:9种有机氯的线性关系良好,相关系数均大于0. 995;最低检出限为0. 00012μg/g～0. 00057μg/g;检测仪器精密度良好,RSD均小于5%;检测方法重现性好,RSD均小于8%;回收率范围在94. 91～105. 09%。参考《中国药典》和《药用植物及制剂外经贸绿色行业标准》收载的品种项下"农药残留量"部分检查限度,50批中药材检出含有机氯农药检出率占74%,但含量均较低,其中总六六、总滴滴涕和五氯硝基苯超标率分别为16%、12%和4%,50批中药材整体合格率达68%,整体符合要求。结论:气相色谱检测法简便快捷、分离效果好,能广泛用于中药材有机氯农药残留的检测。     

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.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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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.     

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     

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。