汽车防冻液的研究与发展

本文概述了国内外汽车防冻液的研究、发展趋势并指出了防冻液今后的发展前景,并就国内外汽车防冻液的现状以及未来的发展做了详细的阐述.按照试剂组成将防冻冷却液分为以无机盐为主的常规防冻液类型和以有机酸为主的防冻液类型.普通防冻液的成分中含有对生命和环境有害的物质,而用于高档汽车的有机酸长效型环保防冻液的配方,由于价格昂贵的原因在应用方面受到了限制.因此,开发了有机酸和无机盐相结合的具有经济、高效和环保等优点的新型防冻液.新开发的防冻液产品,符合汽车防冻液质量、效能等各方面要求,可广泛应用于各类中高档汽车.     

碳钢表面氧化物对硅酸盐界面缓蚀作用的影响

通过吸附实难、XRD等方法研究了模拟碳钢表面氧化物对硅酸盐在金属表面吸附过程的影响;用极化曲线法研究了硅酸盐在碳钢表面氧化物上的电化学行为;讨论了在Fe/FeOOH/硅酸钠溶液体系中,温度、pH、金属离子、硅酸盐稳定剂等因素对硅酸钠界面缓蚀作用的影响。     

AZ71-Gd镁合金压铸件微弧氧化处理工艺研究

采用硅酸盐体系对AZ71-Gd镁合金压铸件进行了微弧氧化处理,研究了工艺参数和溶液成分对微弧氧化膜性能的影响,确定了硅酸盐体系中进行微弧氧化处理的最佳工艺方案为：微弧氧化电流1．5A／dm2,氧化时间15min,电解液温度35℃,硅酸钠12g/L,氢氧化钠2g/L,氟化钾4g/L,有机醇WOH6mL／L。     

太阳能供暖用新型流体制备及导热性能测试

严寒、寒冷地区液体型集热器应用时需考虑防冻性能，工程常使用乙二醇型防冻液作为循环工质。但其导热系数仅为水的60%,集热循环过程中防冻液与太阳能集热器基板传热不充分导致基板过热和集热热损过大。为解决上述问题，通过乙二醇型防冻液及相变材料配制不同浓度的传热蓄热流体(heat transfer and heat storage fluid, HTHSF),在考虑防冻的基础上，以增加HTHSF综合导热系数为目的，通过瞬态热线法实验研究HTHSF相变过程中导热系数的变化规律。结果表明：当温度升高或浓度减小时载流体导热系数增大。配制的HTHSF呈水基溶液的特性，在单一相时导热系数与温度呈正比关系，相变使得导热系数有所减小。寒地太阳能供暖用新型HTHSF 10%、冰点-20℃时性能较好，此外拟合公式与实测数据误差在0.5%以内。     

防冻液及其防腐性能的研究

以工业丙三醇为冷却剂和以钼酸盐为基的多组分缓蚀剂，制备了几组配方的防冻液，研究了它们的防冻性能和金属防腐性能，并从中确定了一个最佳配方．结果表明，按该配方配制的防冻液冰点可达-30℃以下，它对钢、铁、黄铜及铝合金等多种金属均有良好的缓蚀作用．与传统的以无机盐（氯化钙、氯化钠等）或乙二醇为主要原料的防冻液相比，丙三醇防冻液具有原料易得、价格低廉、配制方便、冰点较低、沸点较高、金属防腐性好、对环境污染小、使用寿命长等优点．还具备极好的防结垢性．完全可以达到各种内燃机水冷却系统的要求．有较好的应用前景．     

δ-层状结晶二硅酸钠的制备

为了寻求三步法制备δ-层状结晶二硅酸钠的最佳工艺参数,以速溶粉状二硅酸钠为原料,探讨了干燥温度、干燥时间、调质粉水分含量、结晶温度和结晶时间对试样Ca2 交换能力的影响.实验结果表明:最佳工艺条件为干燥温度300℃,调质粉水分质量分数为8%～10%,结晶温度720℃,结晶时间30 min,此时试样的Ca2 交换能力均值为338 mg/g,Mg2 交换能力均值为392 mg/g,X射线衍射分析亦表明试样的δ相含量较高.     

WB—1型长效汽车防冻液的研制

研制了WB－1型汽车发动机防冻液，讨论了缓蚀剂的选择与复配关系及稳定剂和添加剂的选用，确定了乙二醇型防冻液的组成，并对防冻液的各项性能进行了测试，结果表明，WB－1型防冻液各项技术指标均达到美国ASTMD3306－94标准。     

废CNG/汽油两用燃料发动机油絮凝再生工艺

针对废CNG/汽油两用燃料发动机油,采用正交试验方案,优化设计絮凝试验,考察了硅酸钠溶液浓度、硅酸钠溶液加量、搅拌温度、搅拌时间、搅拌速度、沉降温度和沉降时间等因素对废机油再生质量的影响;得出了废CNG/汽油两用燃料发动机油再生的最佳工艺参数:硅酸钠溶液浓度为20%,硅酸钠溶液加量为10%,搅拌温度为75℃,搅拌时间为20 min,搅拌速度为1 000 r/min,沉降温度为70℃~80℃,沉降时间为16 h以上。     

牛奶纤维／棉混纺针织物的漂白工艺

研究了双氧水质量浓度、碳酸钠质量浓度、硅酸钠质量浓度、尿素质量浓度、渗透剂质量浓度、时间、温度、浴比等因素对牛奶纤维/棉混纺针织物漂白效果的影响.根据正交实验得出较优的牛奶纤维/棉混纺针织物漂白工艺:双氧水质量浓度25g/L,碳酸钠质量浓度4g/L,渗透剂JFC质量浓度2g/L,硅酸钠质量浓度4g/L,尿素质量浓度7g/L,浴比1∶20,时间60min,温度90℃.实验结果同时表明弱碱环境下,牛奶纤维/棉混纺针织物过氧化尿素氧漂的效果优于过氧化氢氧漂的效果.     

以麦秸为原料同时制备超级电容器和纳米分子筛的联产工艺

我国小麦秸秆资源极为丰富,其中含有大量的碳、硅元素,因此提出了以麦秸为原料,同时制备超级电容器和纳米分子筛联产工艺的设想.目前粉碎还田是麦秸的主要处理方式,处理过程中存在着一系列问题.本联产工艺先将麦秸用碳化机处理得到生物炭,研磨后加入氢氧化钠溶液,抽滤洗涤,分别得到滤渣和含硅酸钠的滤液,再从滤渣中得到活性炭制备超级电容器,从含硅酸钠的滤液中得到二氧化硅制备纳米分子筛.本联产工艺旨在提出一种农业废弃物的回收处理方式,在麦秸高效利用的同时,提出环境友好型、可能应用到实际中的麦秸利用途径,有利于加快建立健全绿色低碳循环发展经济体系.     

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