聚乙烯吡咯烷酮对果树叶片中POD活性的影响

用联苯胺比色法测定了玖瑰香葡萄、鸭梨、杏和毛桃叶片中ＰＯＤ活性。结果表明：不同ＰＶＰ加入量对果树叶片的ＰＯＤ活性有很大影响，ＰＶＰ加入量为０．１２５ｇ时，玖瑰香葡萄叶片的ＰＯＤ活性最大；加入０．０５ｇＰＶＰ时，杏叶片的ＰＯＤ活性最大；加入０．２ｇＰＶＰ时毛桃叶片的ＰＯＤ活性最大（叶片均取０．５ｇ左右。）     

磁水对玉米幼苗生理生化效应的初步研究

用不同磁场强度（０．０５Ｔ、０．１０Ｔ和０．１５Ｔ）的磁水处理玉米种子、幼苗，发现一定磁场强度的磁水能提高叶片中叶绿素含量、硝酸还原酶（ＮＲ）活性，但降低ＩＡＡ氧化酶活性、呼吸速度和电导率．结果表明：磁水具有增强玉米幼苗进行光合作用、氮代谢和抑制ＩＡＡ降解、提高其抗冻性的效应．     

玉米幼苗两种形态建成中3个生化指标的比较研究

采用ＰＡＧＥ方法，对玉米幼苗和暗形态建成过程中ＥＳＴ、ＰＯＤ各可溶性蛋白进行比较研究后发现：光促进分化而抑制生长，暗则与此正相反；光或暗条件下各自都有部分基因特异性表达，植物能够适应光与暗的环境，进行形态建成。     

山海关杨扦插生根过程中几种生理生化指标的变化

以易生根的山海关杨为处理、不易生根的毛白杨为对照 ,对扦插生根过程中不同时间的POD酶活性、I AAO酶活性及酚含量进行了测定。结果表明 ,易生根的山海关杨与毛白杨有较大区别 ,而与以前所做毛白杨嵌合体在 3项指标变化曲线中有较大的一致性。山海关杨POD酶活性从扦插后开始较高 ,到第 4天降到低谷 ,以后再升高 ,第 8天为一高峰 ,以后再降低之后波动 ;IAAO活性与POD酶活性基本上恰好相反 ;酚含量总体趋势是前期较低后期较高     

鲁白15对土壤中重金属铅的吸收及其生理生化指标SOD、POD变化的研究

通过盆栽实验研究了在不同浓度的Pb2 处理下,加入土壤后对鲁白15吸收Pb2 的影响。结果表明: 随着土壤中Pb2 浓度的增高,鲁白15地上部分和根系含铅量也增高。当Pb2 浓度达1 000 mg/kg时其含铅量达最大值,而且对其外观毒性效应影响不很显著。因此鲁白15对铅有较好的耐性,能较好地适应在受铅污染的土壤中生长。同时研究了在不同Pb2 浓度作用下,其POD、SOD的活性和受害生成物丙二醛的含量变化。     

紫丁香花开放与衰老中几项生化指标的研究

对紫丁香花开放过程中 4个不同时期的生化指标进行了测定。结果表明 ,随着花朵的开放和衰老 ,花瓣中的可溶性蛋白质含量逐渐降低 ,可溶性糖的含量和超氧化物歧化酶 (SOD)的活性先升后降 ,丙二醛 (MDA)含量逐渐上升 ,过氧化物酶 (POD)的活性表现为先降后升。     

男子古典摔跤运动员长期大强度训练中几种生理生化指标的变化

综述当前国际上对生理生化学的研究工作,包括运动员长期大强度训练对生理生化的影响。长期大强度训练对CK、血色素及血蛋白的制约,提出了合理安排训练的重要性。     

几种物料中f-CaO的膨胀特性及其对硬化水泥浆体强度的影响研究

不同物料中f-CaO的水化活性、膨胀特性及其对硬化水泥浆体强度的影响各不相同.高钙粉煤灰中的f-CaO水化最快,试样膨胀主要发生在7天以内;水泥熟料中的次之;钢渣中的水化最慢,试样膨胀稳定期超过56天.掺高f-CaO熟料的试样强度最高;掺高钙粉煤灰者次之;掺钢渣者强度最低.     

糙皮侧耳裂殖过程中几种碳源胞外酶系活性变化规律的研究

本文主要研究了糙皮侧耳菌丝静态繁殖过程中及断裂繁殖过程中胞外酶活性变化.测定了淀粉酶、羧甲基纤维素酶、半纤维素酶及滤纸纤维素酶的活性变化.结果表明,断裂繁殖对于淀粉酶、FP酶的活性的提高有积极的影响.这对纤维素的分解与利用具有重要的意义.     

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.     

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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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.