双季铵盐表面活性剂的合成及表面活性研究

用脂肪酸制备了乙撑双(二甲基)季铵盐基双脂肪酸甲酯(B)及乙撑双(二甲基)季铵盐基双脂肪酸钠盐(C),用红外光谱对其结构进行了表征.经测定,分别用十二酸和十四酸制备的B1和B2其临界胶束浓度(cmc)分别为1.4×10-4和2.2×10-4 mol/L,其表面张力(γcmc)分别为30.5和37.8 mN/m;C1和C2的cmc分别为7.8×10-5和3.0×10-4 mol/L,γcmc分别为28.9和36.9 mN/m.结果表明,与普通表面活性剂相比,双子表面活性剂B1和B2的cmc要低1～2个数量级,γcmc也低了2～9个mN/m;C1、C2的cmc仅为普通表面活性剂的1/60～1/230,而γcmc相差不大.     

深层发酵香菇水溶性胞外多糖的分离纯化及性质分析

香菇（Lentinusedodes）CL－2深层发酵上清液经乙醇沉淀、除蛋白、透析、DEAE－纤维素（DE－32）和SephadexG－200凝胶柱层析得到纯的水溶性胞外多糖（HEP）．DNS法检测和IR分析证实,HEP为多糖类物质,且在200～400um近紫外区不吸收．经PC、GC、IR和甲基化分析,确定其基本结构是以β－1,4键连接为主链并具有β－1,6键支链的甘露葡聚糖．同时还具有少量的β－1,2和β－1,3键．葡萄糖和甘露糖的摩尔比为1：0．0852．     

小茴香萃取物中脂肪酸成分的GC-MS分析

对宁夏固原种植的小茴香籽油用正已烷进行了回流提取物,萃取物经皂化和甲酯化反应处理后,利用气相色谱－质谱（ＧＣ－ＭＳ）进行分析,鉴定了产物中的脂肪酸组分,结果表明,１７种脂肪酸中,含量最高的是十八碳烯－５－酸（７８．５６２％）,其次是十八碳二烯酸（８．３５２％）、棕榈酸（７．２５９％）和硬脂酸（２．１０３％）。     

棒束孢霉胞外多糖的纯化

棒束孢霉发酵上清液经减压浓缩、醇析、蛋白酶法与Ｓｅｖａｇ法结合脱蛋白、逆向流水透析和ＤＥＡＥ－ＳｅｐｈａｄｅｘＡ－５０柱层析等步骤，获得了胞外纯多糖。用ＴＬＣ、ＧＣ及ＩＲ分析表明，该多糖链由Ｄ－甘露醇和Ｄ－半乳糖组成。     

β-环糊精/碳微球复合材料的制备和表征

以可溶性淀粉为原料,经水热处理、产物的高温碳化制备碳微球;并以β-环糊精和碳微球为原料经反相乳液法制备β-环糊精/碳微球复合材料;利用红外光谱、扫描电子显微镜、X射线光电子能谱、X射线衍射等手段对产物的结构和性质进行了表征。结果表明:以可溶性淀粉为原料制得了粒径约5μm的单分散碳微球;同时也成功地制备了表面光滑、粒径约15μm的β-环糊精/碳微球复合材料。     

HCV多表位抗原基因与β-半乳糖苷酶基因融合表达、产物纯化及酶活性分析

设计一个270bp的丙型肝炎病毒（HCV）复合多表位抗原基因（PCX）,与β－半乳糖苷酶（GZ）基因融合后,在高浓度肉汤培养基中,于转接1％量后3．25h,用终浓度为1mmol／LIPTG诱导4h发酵表达,其表达量最高,约占50％总蛋白量,表达产量GZ－PCX以包含体形式存在．利用改良的包含体纯化及溶解方法,可获得溶解率＞90％,纯度为96．2％的产物GZ－PCX,且包含体溶解产物较好保存其蛋白酶活．对PBS／EDTA透析,GZ－PCX蛋白的β－半乳糖苷酶活性可升高4倍,对H2O／EDTA透析其活性则明显下降．     

一种新型甜菜碱型沥青乳化剂的合成及在线红外光谱分析

以月桂醇、环氧氯丙烷、二甲胺、氯乙酸经三步反应合成出一种新型甜菜碱型沥青乳化剂.确定了第一步合成2-(十二烷氧基亚甲基)环氧乙烷的最佳反应条件,其收率为75.7%.利用红外光谱对3种产物结构进行了表征,利用在线红外光谱技术对第一步合成2-(十二烷氧基亚甲基)环氧乙烷的反应进行追踪分析,检测出中间体.基于以上实验数据,提出了合理的反应机理.最终产物的临界胶束浓度为8.8×10-5mol/L,在临界胶束浓度下的表面张力为21.2 mN/m.该乳化剂属于中裂型沥青乳化剂.     

短裙竹荪菌丝体糖蛋白DdGP-3P3纯化及性质研究

短裙竹荪菌丝体经热水抽提，乙醇分级沉淀，级分3经DEAE－Cellulose柱层析纯化得到短裙竹荪菌丝体糖蛋白DdGP-3P3。经测定该糖蛋白为均一组分，相对分子质量为113KDa，红外光谱呈现出典型的多糖吸收峰，含有β－型糖苷连接键。β－消去反应测定，该糖蛋白中糖和蛋白质的连续键为O－型糖肽键。纸层析和气相层析分析得知DdGP-3P3含有D－葡萄糖（D－glucose)、D-甘露糖（D－Mannose)和D－半乳糖（D－galactose)，其摩尔比为2．01：1．00：1．23。氨基酸分析表明它含有16种氨基酸。     

乙二醇双子琥珀酸2-甲基戊基酯磺酸钠的合成及性能

采用酯化反应无需有机溶剂为介质、以碳基固体酸作酯化反应催化剂、磺化反应不外加相转移催化剂在常压下反应的新方法合成了乙二醇双子琥珀酸2-甲基戊基酯磺酸钠,最佳工艺条件为：单酯化反应,n（乙二醇）：n（顺酐）：l_00：2．10,催化剂碳基固体酸用量为顺酐质量的2％,于100℃反应4．7h,酯化率99．02％（质量分数）;双酯化反应。n（2-甲基-l-戊醇）：n（顺酐）=1-30：1．00,于210℃反应1．2h,酯化率95．34％（质量分数）;磺化反应,n（亚硫酸氢钠）：n（顺酐）：1．05：1．00。于油浴120℃反应3．2h,磺化率100．64％（质量分数）．对产物结构进行了IR光谱表征,测定了产物性能：CMC为2．5×10。mol／L,7cMc为27．79mN／m,乳化力为11．5min,渗透力为6s,耐硬水力为13．5min．比较了碳基固体酸和无水乙酸钠、对甲苯磺酸对酯化反应的催化效果,结果表明：碳基固体酸对酯化反应的催化效果好．且易于分离．     

新型1，8-萘酰亚胺衍生物的合成及其分子内光致电子转移

合成了4－哌吡嗪基－N－甲基－1,8－萘酰甲亚胺（NA1）及其衍生物。化合物NA1和4－（4－甲基－1－哌吡嗪基）－N－甲基－1,8－萘酰亚胺（NA2）分子内的脂肪胺作为电子给体,通过双碳链向萘酰亚胺进行光致电子转移,使得N－甲基－1,8－萘酰亚胺荧光团的荧光猝灭;脂肪胺质子化或季铵化后,光致电子转移过程中断、荧光恢复。这类化合物的荧光随pH值的变化而变化,表现出的荧光分子开关功能。     

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。     

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.     

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