稀土钇对含Zn和Mg铸态铝合金相组成物的影响

研究了Ｙ在Ａｌ－（１－５）％Ｙ,Ａｌ－８％Ｚｎ－（１－５）％Ｙ,Ａｌ－２％Ｍｇ＿１－３）％Ｙ及Ａｌ－８％Ｚｎ－２％Ｍｇ－（０－５）％Ｙ合金中的存在形态及对该合金铸态组织的影响。结果表明,在Ａｌ－Ｙ及Ａｌ－２％Ｍｇ－Ｙ合金中,Ｙ以Ａｌ３Ｙ形态存在;在Ａｌ－８％Ｚｎ－２％Ｍｇ和Ａｌ－８％Ｚｎ合金中以Ｙ１２Ａｌ３Ｚｎ金属间化合物的形态存在下晶界,在Ａｌ－８％Ｚｎ－２％Ｍｇ中,Ｙ的存在还能改变Ｚｎ和Ｍｇ在     

Ti—Al—Y三元系相图1000℃部分等温截面重新确定

利用扩散偶局部平衡原理，通过金相观察和电子探针微区成分分析，重新测定了１０００℃下Ｔｉ－Ａｌ－Ｙ三元部分等温截面相图。首次发现该系在１０００℃存在两个三元化合物均相区Ｙ（ＡｌｘＴｉ１－ｘ）２（ｘ＝８０％￣１００％）和Ｙ３（ＡｌｘＴｉ１－ｘ）２（ｘ＝８０％￣１００％）改变了以前发表的关于Ｔｉ－Ａｌ－Ｙ三元相图１０００℃等温截面的研究结果。此外在所测部分等温截面相图中存在６个单相区，９个两相平衡区，４     

植物生长调节剂和蔗糖对抗黑胫病香果树丛芽分化的影响

将抗黑胫病香果树愈伤组织在ＢＡ、ＮＡＡ、蔗糖３因素条件下作Ｌ＿９（３￣４）正交组织培养试验．结果表明，ＢＡ、ＢＡ与ＮＡＡ的交互作用对抗病香果树愈伤组织丛芽分化有极显著影响．ＢＡ／ＮＮＡ（Ｘ）与芽分化（Ｙ）的关系为Ｙ＝１．３６５１Ｘ￣（０．１２８６），ＢＡ／ＮＡＡ（Ｘ）和ＢＡ＋ＮＡＡ（Ｙ）与芽分化（Ｚ）的关系为Ｚ＝１．１０３３＋０．０９９９（Ｘ＋Ｙ）－０．００２７（Ｘ＋Ｙ）￣２，ＢＡ／ＮＡＡ（Ｘ）和蔗糖浓度（Ｙ）与芽分化（Ｚ）的关系为Ｚ＝１．０７４０＋０．０７９３（Ｘ＋Ｙ）－０．００１７（Ｘ＋Ｙ）￣２．在本该试验范围内，丛芽分化的最适培养基为ＭＳ＋ＢＡ２ｍｇ／Ｌ＋ＮＡＡ０．１ｍｇ／Ｌ＋蔗糖３％．     

新的NS配体CYCA的合成、~(99m)Tc标记及动物分布的研究

为了探索结构与生物分布性质的关系，合成了一种新的ＮＳ配体Ｌ－半胱氨酸酞－对氯苯胺盐酸盐（ＣＹＣＡ）．以ＳｎＣｌ２为还原剂，制备了放化纯大于９３％的９９ｍＴｃＯ－ＣＹＣＡ．探讨了ｐＨ值和反应温度对９９ｍＴｃＯ—ＣＹＣＡ标记率的影响，并对其小鼠生物分布进行了研究．结果表明，９９ｍＴｃｄ－ＣＹＣＡ在脑和心肌中具有一定的浓集，在肝脏中有较高浓集，并且清除速度较慢．这些结果对于探索结构与生物分布性质的关系提供了参考．     

Al2O3颗粒弥散强化Y—PSZ基复合陶瓷的R曲线

利用维氏压痕／抗弯强度法对３Ｙ－ＰＳＺ单体和３Ｙ－ＰＳＺ／２０％Ａｌ２Ｏ３复合陶瓷的裂纹扩展曲线进行了测试。结果表明，与裂纹扩展初期引比，Ａｌ２Ｏ３颗粒的弥散增韧效果随着裂纹的扩展而明显上升，除裂纹偏向以外，Ａｌ２Ｏ３弥散颗粒是通过架桥和拔出等方式来进一步提高３Ｙ－ＰＳＺ陶瓷的断裂韧性的。     

乙肝病毒表面抗原SA-28融合基因在酵母中的组成型表达

以酵母载体ＹＦＤ５９为基础,将乙肝病毒表面抗原ＳＡ－２８融合基因正向插入组成型启动子ＰＰＧＫ１及终止子ＴＰＧＫ１间,得到表达载体ＹＦＤ５９－ＬＳＳ１。并将该表达载体分别转化ＢＪ２１６８,ＤＢＹ７４６,ＪＲＹ１８８,ＢＪ３５０５ ４株不同的酿酒酵母株。再将ＹＦＤ５９－ＬＳＳＩ质粒上的表达单元克隆至高稳定载体ｐＨＣ１１的ＢａｍＨⅠ位点,构建成３个带有不同拷贝数和不同插入方向表达单元的表达载体;ｐＨＣ１     

含钇ZA—27系列合金相结构特征分析

采用Ｘ－射线衍射分析、拉伸断口扫描电镜分析及微区能谱分析方法，对添加不同钇含量的ＺＡ－２７系列锌合金的析出相进行系统分析和研究。结果表明，当钇含量在０．０３５％ｗｔ范围内，钇主要与铝生成细小、弥散的ＹＡｌ３相。当钇含量达到０．１７％ｗｔ时，合金除了生成ＹＡｌ３相外，有ＹＺｎ１２相生成，随着钇的增加，钇－锌相逐渐增多并长大，当钇含量达到或超过０．５９％ｗｔ时，合金中出现块状的钇－锌相，并有Ｙ２Ｚｎ１７相生成。     

电场诱导酵母菌原生质体融合的研究──原生质体分离、电融合条件及其机制的研究

研究了热带假丝酵母野生株１０４５及其突变株ＳＤ１的原生质体分离、电击诱导融合的诸条件以及融合子的再生。得出了原生质体的最佳生成条件。用９９９ｋＨｚ，２４０～４００ Ｖ／ｃｍ的高频交变电场使原生质体横向电泳形成珠串，以脉宽 ４０ μｓ，幅值 １６００～２ ８００ Ｖ／ｃｍ的直流脉冲可使原生质体融合，净融合率达６５％。采用较低幅值的多个脉冲有利于融合。电击液中加入ＣａＡｃ场、ＭｇＡｃ２及白蛋白可大大提高融合率，用光刻镀金方法设计了适用于微生物的多电极融合小室。对膜融合机制进行了探讨。     

一种YAG激光眼科治疗仪的光学系统

介绍了一种分体测立式ＹＡＧ激光眼科治疗仪的光学系统。治疗头与裂隙灯显微镜光学系统相互独立，它具有二级扩束，Ｈｅ－Ｎｅ光对ＹＡＧ光共轴指示，ＹＡＧ激光焦斑直径ｄＹＡＧ＝（３０±５０）μｍ，光强度满足进行眼科手术的要求。     

光纤耦合的LKD泵浦微型固体激光器

本文报导了一种光纤耦合的ＬＤ泵浦微型Ｎｄ：ＹＡＧ固体激光器，该激光器为连续波输出，最大输出功率达３２．５ｍＷ，斜率效率为１３．９％，这种连续波输出的Ｎｄ：ＹＡＧ激光器，可作为实验室的激光源使用。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to