应用fermion—spin理论研究t—J模型的基态性质

应用ｆｅｒｍｉｏｎ－ｓｐｉｎ理论，研究了氧化物超导材料的基态性质。平均场结果说明在没有掺杂的半满情况下，系统处于磁性的π－ｆｌｕｘ状态。在掺杂情况下，讨论了系统的动能、相分离、与掺杂有关的反铁磁长程序等问题，结果与实验及数值模拟结果符合较好。     

Hubbard－Hirsch模型的超导性

应用么正变换微扰论和平均场近似研究了二维Ｈｕｂｂａｒｄ－Ｈｉｒｓｃｈ模型的超导性。在大Ｕ和中等掺杂情况下，只要跳跃常数足够大，模型仍然具有超导性，此时交换作用积分使它的超导相区域比相应的Ｈｕｂｂａｒｄ模型的区域小很多。     

一维Hubbard－Hirsoh模型的铁磁性

应用么正变换微扰论和平均场近似研究了一维Ｈｕｂｂａｒｄ－Ｈｉｒｓｃｈ模型的铁磁性，无论单中心积分常数Ｕ多大，只有双中心的交换积分常数Ｊ″＞０，才可能有铁磁性．掺杂结果不利于铁磁性，使铁磁相的区域比无掺杂的半满情况减少．     

1－（1－H－苯并三唑－1－乙酰基）－4－苯甲酰基氨基硫脲及其噻二唑和三唑啉衍生物的合成

于固液相转移条件下，以ＰＥＧ－６００为相转移催化剂，通过苯并三唑与氯乙酸乙酯反应，合成了１－Ｈ－苯并三唑－１－乙酸乙酯（Ⅱ）．Ⅱ与８５％的水合肼反应，制得相应的酰肼（Ⅲ）．Ⅲ与苯甲酰基异硫氰酸酯反应，则得１－（１－Ｈ－苯并三唑－１－乙酰基）－４－苯甲酰基氨基硫脲（Ⅳ）．Ⅳ在酸或碱存在下环化，分别得到１，３，４－噻二唑（Ⅴ）和１，２，４－三唑啉－５－硫酮。     

三维Hubbard－Hirsch模型的铁磁性

应用么正变换微扰论和平均场近似研究了三维Ｈｕｂｂａｒｄ－Ｈｉｒｓｃｈ模型的铁磁性．发现单中心积分常数Ｕ太小或太大时，只有双中心的交换积分常数Ｊ″＞Ｊ″Ｃ＞０，才可能有铁磁性．而Ｕ为中间值时，Ｊ″＝０需要用其他方法进一步研究．掺杂结果不利于铁磁性，使铁磁相的区域比无掺杂的半满情况减少     

糠醛－油，N－甲基－2－吡咯烷酮－油汽液平衡和虚拟组分法研究

用改进的Ｅｌｌｉｓ平衡釜，采用化学分析、微型萃取和气相色谱模拟实沸点蒸馏相结合的方法，测定了糠醛－提余油，糠醛－抽出油，Ｎ－甲基－２－吡咯烷酮提余油，Ｎ－甲基－２－吡咯烷酮－抽出油四个系统在常压下的汽液平衡数据。应用虚拟组分法，采用Ｃｈａｏ－Ｓｅａｄｅｒ混合模型对实验数据进行了关联，取得了较好结果。     

三聚氯氰存在下的（2－环己酮基）－β－丙酸与（R）－四氢噻唑－2－硫酮－4－羧酸酯反应

在三聚氯氰存在下，（２－环己酮基）－β－丙酸与（Ｒ）－四氢噻唑－２－硫酮－４－羧酸酯（甲酯、乙酯、正丁酯、正戊酯）反应，得到相应的Ｎ－（２－环己酮基）－β－丙酰－（Ｒ）－四氢噻唑－２－硫酮－４－羧酸酯１（ａ～ｄ），［α］＿Ｄ￣（２０）分别为－５０．３°，－５０．９°，－５０．０°，－７８．１°．１（ａ～ｃ）与Ｒ，Ｓ－α－苯乙胺反应得到了光学活性的Ｎ－（２－环己酮基）－β－丙酰－α－苯乙胺及Ｒ过量的α－苯乙胺．     

用H－ZSM－5分子筛作催化剂合成乙酸丁酯

用Ｈ－ＺＳＭ－５沸石分子筛作催化剂，在釜式反应器内对丁醇和乙酸的酯化反应进行了研究，考察了分子筛的焙烧温度、硅铝比、催化剂用量、反应物摩尔比和反应温度等对酯化反应的影响。结果表明，当醇酸比为１．２，在５５０℃下焙烧的Ｈ－ＺＳＭ－５（５０）用量为３％，反应温度为１２０℃时，反应５小时乙酸的转化率大于９２％，提出了在无催化剂和以Ｈ－ＺＳＭ－５为催化剂情况下酯化反应动力学模型。     

1－羟基－2－（2－苯并噻唑偶氮）－8－氨基－3，6－萘二磺酸试剂的应用和性能研究

本文对一新合成的偶氮试剂－１－羟基－２－（２－苯并噻唑偶氮）－８－氨基－３，６－萘二磺酸（ＨＢＡＤ）作为酸硷指示剂及和某些金属离子的显色反应进行了研究。该试剂用做酸碱指示剂，其变色域为５．４０（紫红）－７．００（纯兰），指示剂离解常数ｐＫ＿（１ｎ）。为６．７０（２０℃）。在滴定终点时，变色敏锐。用该试剂作为指示剂对Ｈ＿２ＳＯ＿４、ＮａＯＨ和ＮＨ＿３Ｈ＿２Ｏ的含量进行丁滴定分析，获得了较满意的结果。该试剂在适当的ｐＨ条件下可和Ｃｕ￣（２＋）和Ｎｉ￣（２＋）等金属离子发生显色反应。     

S－系统F（＋，·，1）的值位与赋值Near－环

本文给出赋值Ｎｅａｒ－环、Ｓ－系统赋值和Ｆ－值位的定义并进行了研究，得出Ｓ－系统等价的值位类与赋值Ｎｅａｒ－环之间的对应关系。     

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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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。     

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.     

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