铝基润滑脂凝胶的制备、结构及流变性

采用一步法 ,以硬脂酸、SAE 30润滑油和异丙醇铝为原料制备铝基润滑脂凝胶 .电镜观察的结果表明该凝胶具有由铝皂微粒构成空间网络骨架 ,并在其空隙中填充分散介质形成凝胶的结构特征 .应用粘度计对其流变性的研究发现该凝胶属胀流体 ,并在温度较高时接近Newton流体 ,当皂分质量分数在 1 1 .2 %时 ,润滑脂表观粘度最大 ,且在 40℃以上时呈现较好的粘温性能     

铝颗粒对乙醇胺凝胶性能的影响

采用乙醇胺、琼脂糖胶凝剂、含能颗粒铝制备系列燃料凝胶。利用量热仪、离心机、旋转流变仪等仪器考察了胶凝剂和铝颗粒添加量（质量分数）对凝胶热值、离心稳定性、流变性的影响；通过扫描电镜对铝、琼脂糖颗粒及凝胶微观形态进行了表征。结果表明：当铝颗粒质量分数为30%时，相较于纯凝胶，乙醇胺凝胶体积燃烧热提高了22.2%，离心析液率从26.5%下降到9.8%，稳定性大大增强；铝颗粒能够与凝胶相结合增强凝胶的网络结构、增加松弛时间和储能模量。     

凝胶因子的合成及在有机溶剂中的聚集现象

分别以几种小分子氨基化合物为结构骨架,连接长链烷基,合成了4种新型凝胶因子,其结构通式为R－OCHN－X－NHCO－R,这4种凝胶因子是一类很好的凝胶化试剂,以极低的浓度就可以使DMSO等多种溶剂凝胶化,形成热力学可逆的有机凝胶,透射电子显微镜证明4种凝胶因子在有机溶剂中,可以自我组装成延伸的螺旋缠绕细纤维结构,并进一步组装形成三维的空间网络结构,红外研究表明聚集过程中伴随有氨在之间氢键的形成。     

基于骨架提取的WSN信息存储和检索算法

针对在无线传感器网络中信息存储和检索效率容易受到节点负载不均匀和距离不敏感限制的问题,引入网络散度概念,并在此基础上提取网络的骨架;利用骨架能够代表拓扑几何的特性,提出一种负载均衡、距离感知的信息存储和检索算法.该算法不要求节点的地理信息,也不受网络形状的限制,一次数据检索可以沿着简单的路径成功检索到所感兴趣的数据.仿真表明:该算法检索路径较短且取得更佳的负载均衡,从而有效地减少了网络能耗,延长网络生命周期.     

8-羟基喹啉铝处干SiO气凝胶纳米孔中的光谱特性研究

制备了块状的SiO气凝胶，把具有很好电致发光(EL)和光致发光(PL)性能的8-羟基喹啉铝渗入到气凝胶的纳米孔洞中。可见—紫外吸收光谱表明8-羟基喹啉铝在SiO气凝胶的纳米孔洞中发生了化学吸附，且吸附作用随着气凝胶密度的减小而增强；PL谱中8-羟基喹啉铝的光致发射谱峰从470nm移至450nm。     

8—羟基喹啉铝处于SiO2气凝胶纳米孔中的光谱特性研究

制备了块状的ＳｉＯ２气凝胶,把具有很好电致发光（ＥＬ）和光致发光（ＰＬ）性能的８－羟基喹啉铝渗入到气凝胶的纳米孔洞中,可见－紫外吸收光谱表明８－羟基喹啉铝在ＳｉＯ２气凝胶的纳米孔洞中发生了化学吸附,且吸附作用随着气凝胶密度的减小而增强：ＰＬ谱中８－羟基喹啉铝的光致发射谱峰从４７０ｎｍ移至４５０ｎｍ。     

变形介质储层的砂渗流机理研究

变形介质储层的开采过程是一个流固耦合渗流过程.当储层岩土的变形超过其极限,岩土骨架将遭到破坏产生骨架砂,这些骨架砂在流体的作用下运移、沉降或者堵塞储层孔隙喉道必将影响储层流体的渗流及岩土骨架的变形.由于在常规变形介质储层渗流机理的研究中没有考虑骨架砂的产出,因此其渗流数学模型不能准确描述这些储层流体的实际流动状况.本文在常规变形介质储层渗流理论研究的基础上,首先建立了储层出砂的判断准则,然后建立了变形介质储层出砂渗流的三维四相多组分数学模型并探讨了其求解方法.该模型的建立对于正确认识和高效开发变形介质储层有着重要意义.     

润滑脂对滚动轴承EHD膜厚的影响

用电阻应变片法在滚动轴承上测试各种类型润滑脂的弹性流体动压润滑(EHD)膜厚h_c。结果表明,h_c与基础油的粘度密切有关,且受到皂的类型及浓度的影响。提出了不同工况下适宜的润滑脂类型及其浓度的选用原则。     

气凝胶及其纤维复合材料等效导热系数预测

为了研究气凝胶及其纤维复合材料的隔热性能,分别数值重构了几种气凝胶及其纤维复合材料的微细观随机结构,采用格子Boltzmann方法数值求解了它们的等效导热系数,同时用基于瞬态平面热源法的Hot Disk热常数分析仪测量了它们在复杂环境下的等效导热系数。研究表明:骨架连续的开孔型微观结构比骨架不连续的颗粒型微观结构更符合气凝胶的实际结构,开孔型结构等效导热系数的数值预测值与实验值的偏差大部分在±10%内;气凝胶的密度值会影响它的隔热性能,且存在着最佳的密度使得气凝胶的等效导热系数最低;纤维复合气凝胶的等效导热系数随着纤维体积分数的增加而增加;纤维在垂直于热流方向的水平面内随机排布时对气凝胶的隔热性能影响最小。     

基于科氏流量计的流体粘温系数的测定

本文基于弯曲振动粘度测量的原理,利用科氏流量计本身的优点,提出了一种较为方便的测量流体粘温曲线的方法,并选用某型号硅油进行了实验测量,得到了该硅油的粘温曲线和粘温系数。     

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