Fe—C—Cr—Mn系耐磨合金的结构设计

在总结了Ｆｅ－Ｃ－Ｃｒ系铸造金属基础上提出Ｆｅ－Ｃ－Ｃｒ－Ｍｎ系铸造合金碳化物体化比和奥氏体基体成分计算公式，并熔炼一系列实验合金进行了验证，按此计算了方法，可以进行Ｆｅ－Ｃ－Ｃｒ－Ｍｎ系亚稳奥氏体基耐磨合金结构设计，并为进一步实现合金结构设计的计算机模拟打下了基础。     

Cr5Mo／A302异质焊头时效过程中的组织结构变化

利用光学显微镜对ＣｒＭｏ／Ａ３０２异质焊头在高温时效过程中的组织结构变化进行了研究。结果表明珠江体钢／奥氏体钢划质焊头中γ－Ｆｅ与α－Ｆｅ在熔合区有结晶相适应的结晶条件；增碳层与时效时间呈抛物线关系；时效中熔合区附近碳化物转变基本遵循Ｍ７Ｃ３→Ｍ２３Ｃ６→Ｍ６Ｃ；增碳层中析出碳化物与奥氏体基体保持共格关系。     

高铬白口铸铁的组织与相结构研究

本文主要研究耐磨高铬白口铸铁的组织形貌与相结构问题。通过实验确定：比较 理想的合金主要化学组成为 Ｆｅ－１１．３％Ｃｒ－２．８８％Ｃ；经能谱、Ｘ射线及电子衍射 分析确认：该合金中的主要抗磨相为具有六方结构的（Ｃｒ．Ｆｅ，Ｍｏ）７Ｃ３型复合碳 化物、Ｈｖ１３００—１８００： 金相观测表明：该合金的显微组织形貌为：在强韧的回火马 氏体（或回火屈氏体）的连续基体上孤立匀称地分布着“菊花团伏”的高硬度共晶 碳化物（Ｃｒ，Ｆｅ，Ｍｏ）７Ｃ３。     

添加氧化物粉末对FeCr烧结合金交流磁特性的影响

添加氧化物粉末对ＦｅＣｒ烧结合金交流磁特性的影响（日）大同工业大学和大同特殊钢公司技术开发研究所为进一步提高ＦｅＣｒ系烧结合金的交流磁特性，研究了添加ＳＩＯ。、ＣａＯ、ＡＩ。Ｏ。的粉末混合物对低Ｃ的Ｆｅ－１３Ｃｒ－０．ＳＳｉ烧结合金磁性的影响。试验用...     

Fe_3（Al，Cr，Zr）和Fe_3（Al，Cr，Nb）金属间化合物的高温氧化行为

用循环氧化法研究了Ｆｅ－２８Ａｌ－５Ｃｒ－０．１Ｚｒ（ａｔ％）和Ｆｅ－２８Ａｌ－５Ｃｒ－０．５Ｎｂ（ａｔ％）金属间化合物的高温氧化行为．结果表明，含Ｚｒ的Ｆｅ３（Ａｌ，Ｃｒ）金属间化合物在８００℃、１０００℃、５００ｈ循环氧化后形成一个独特的晶须状氧化物层，微量Ｚｒ能增加氧化物层与基体金属的粘附性，从而提高了该合金的高温抗氧化性能．而含Ｎｂ的Ｆｅ３（Ａｌ，Ｃｒ）金属间化合物在１０００℃、３５０ｈ循环氧化后形成多孔的卷绕状形貌，对Ｆｅ３（Ａｌ，Ｃｒ）金属间化合物的高温抗氧化性没有改善．     

奥氏体耐热钢抗渗碳性能的研究

本文通过对 ３６ＸＳ，３６Ｘ．ＨｉＳｉ－ＨＰ，Ｃｒ２５Ｎｉ３８，ＨＰ和 ＨＫ 等 ６种奥氏体耐 热钢在渗碳过程中渗层深度的增加速度、渗碳层最高含碳量等性能的研究．利用电子 探针微区成分分析的方法，深入探讨了 Ｓｉ，Ｎｉ．Ｃｒ．Ｆｅ 等合金元素在渗碳过程中　 的行为和对耐热钢渗碳性能的影响．得到Ｓｉ．Ｎｉ．Ｆｅ 等元素主要通过阻碍碳化物 形成而提高耐热钢的抗渗碳能力；渗碳过程中形成大量碳化物所需耍的 Ｃｒ 主要通 过渗层内基体提供．渗层内总的含 Ｃｒ 量并没增加，因渗层内基体含Ｃｒ量的显著下 降而使其耐氧化腐蚀能力下降。     

铬对高锰奥氏体钢相结构的影响

研究了铬加入高锰奥氏体钢中后，原奥氏体高锰钢组织中出现的一种新相。用Ｘ射线衍射分析确定，该相为Ｆｅ－Ｃｒ超结构相，即铬元素与奥氏体形成有序固溶体。由于铬的加入，使高锰奥氏体钢强化机制发生改变。     

Fe3（Al,Cr,Zr）和Fe3（Al,Cr,Nb）金属间化合物的高温…

用循环氧化法研究了Ｆｅ－２８Ａｌ－５Ｃｒ－０．１Ｚｒ（ａｔ％）和Ｆｅｒ－２８Ａｌ－５Ｃｒ－０．５Ｎｂ（ａｔ％）金属间化合物的高温氧化行为。结果表明，含Ｚｒ的Ｆｅ３（Ａｌ，Ｃｒ）金属间化合物在８００℃、１０００℃、５００ｈ循环氧化后形成一个独特的晶须状氧化物层，微量Ｚｒ能增加氧化物层与基体金属的粘附性，从而提高了该合金的高温抗氧化性能。而含Ｎｂ的Ｆｅ３（Ａｌ，Ｃｒ）金属间化合物在１０００℃、３５０ｈ     

Fe-Ni-Cr玻封合金氧化膜及其封接性能

Ｎｉ４２Ｃｒ６Ｆｅ合金广泛用于制作显象管玻壳阳极帽。为了改善它作为软玻璃的气密性封接材料的性能，采用ＴＥＭ、ＸＲＤ、ＳＥＭ等技术研究此合金表面氧化膜的组成、结构及其气密性封接性能，以选择合适气密封接的氧化膜条件。试验结果表明，氧化初期以Ｃｒ２Ｏ３为主，后期以（Ｆｅ，Ｍｎ）Ｃｒ２Ｏ４为主。氧化膜表面为（Ｆｅ，Ｍｎ）Ｃｒ２Ｏ４，主要起浸润玻璃作用；氧化膜底层为Ｃｒ２Ｏ３，主要起致密稳定和与基体连接的作用。     

Fe（Ⅱ）对Cr（Ⅳ）─I~－体系诱导反应机理的研究

本文考查了下Ｆｅ（Ⅲ）－Ｉ－、Ｃｒ（Ⅳ）－Ｉ－及Ｃｒ（Ⅳ）－Ｉ－Ｆｅ（Ⅱ）体系的反应曲线，证明由于Ｆｅ（Ⅱ）的引入，体系产生Ｃｒ（Ｖ）中间体并快速氧化Ｉ－；通过实验确定Ｃｒ（Ⅳ）－Ｉ－－Ｆｅ（Ⅱ）体系的化学计量关系，导出了诱导反应的机理及速率方程，并通过反应曲线的研究进一步证实了反应机理。     

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