板坯连铸结晶器及振动装置的研究

从传热学和结构力学角度,分析了结晶器的温度场和应力场,采用解析法和有限元法计算了结晶器的热应力和变形.针对原来的正弦振动机构存在的问题,提出了改进方案:采用椭圆齿轮变速器实现非正弦振动,并分析了改造后的结晶器的振动规律.同时,对结晶器与板坯之间的摩擦力加以分析.采用非正弦振动使负滑脱时间短,正滑脱时间长,结晶器向上运动速度与铸坯运动速度差较小.振痕深度大为减轻,减少坯壳与结晶器的摩擦力,减少粘结漏钢,提高连铸机拉坯速度,铸坯表面质量明显提高.     

板坯连铸结晶器及振动装置的研究

从传热学和结构力学角度，分析了结晶器的温度场和应力场，采用解析法和有限元法计算了结晶器的热应力和变形。针对原来的正弦振动机构存在的问题，提出了改进方案：采用椭圆齿轮变速器实现非正弦振动，并分析了改造后的结晶器的振动规律。同时，对结晶器与板坯之间的摩擦力加以分析。采用非正弦振动使负滑脱时间短，正滑脱时间长，结晶器向上运动速度与铸坯运动速度差较小。振痕深度大为减轻，减少坯壳与结晶器的摩擦力，减少粘结漏钢，提高连铸机拉坯速度，铸坯表面质量明显提高。     

板坯连铸结晶器摩擦力计算与影响因素研究

结晶器摩擦力是反映坯壳与结晶器润滑摩擦状况的一个重要参数。因此提出了计算结晶器摩擦力的物理和数学模型，讨论了主要连铸工艺参数如拉坯速度、保护渣、碳质量分数、板坯尺寸和振频等对摩擦力的影响。现场监测结晶器摩擦力的结果验证表明，该模型是可行的，可为深入研究连铸坯的热力学行为提供有利手段。     

板坯连铸结晶器异常预报方法研究

结晶器是钢水凝固成型的核心设备,其内部的传热和摩擦直接决定铸坯的表面裂纹和满钢等各类异常.是实现高效连铸的关键因素.基于功率法检测到的板坯结晶器摩擦力实测数据,对摩擦力的异常预报方法进行了研究.建立了以BP人工神经网络为基础的异常预报模型,并开发出相应软件.对应现场的异常记录,离线预报结果表明:软件能够对满钢、水口断裂及液位波动等各类异常进行预报,并具有一定的预报提前量.证明了方法的可行性,并显示出极大的应用潜力.     

双缸式结晶器液压振动原理及应用

结晶器振动精度一直是我们要提高的重要指标之一。日钢7#8#9#板坯机采用双缸式结晶器液压振动系统，该系统能实现正弦与非正弦振动，可以在线修改振幅与振频等参数，且控制精度高，极大提高了铸坯质量与金属收得率，满足了生产的工艺要求。     

板坯连铸结晶器吹氩对铸坯卷渣的影响

板坯连铸结晶器浸入式水口吹氩使结晶器流场发生改变,引起液面波动,造成铸坯卷渣.为了的这一问题,采用大样电解方法结合扫描电镜技术,研究了板坯连铸结晶器浸入式水口不同吹氩量和吹氩分配方式对铸坯夹杂物的数量和类型的影响,提出了减少卷渣的合理结晶器吹氩量和吹氩分配方式,得出了卷渣占结晶器夹杂物的比例超过半数的结论.分析表明合理的吹氩参数对减少结晶器卷渣有着重要的意义.     

连铸坯凝固过程温度模拟系统的开发和研究

建立了连铸板坯凝固过程温度场数学模型。模型中引入了连铸坯在结晶器中表面热流规律的修正方程。针对板坯形状规则的特点，采用有限差分法建立了数学模型。在MATLAB平台下对二冷区内板坯温度场进行分析模拟，以渐变色形式模拟显示了连铸板坯任意截面温度场的等值线、二维及三维可视化显示，显示结果直观。以某钢厂铸机参数及铸坯尺寸为实例进行了模拟分析。模拟结果表明：连铸坯各测量截面的温度与实际测量温度分布相符。该模拟系统为板坯连铸生产过程工艺参数设定与优化提供了理论依据及有效的分析手段，可应用于实际预测当中。     

板坯连铸粘结型漏钢过程模拟及预报

建立了板坯连铸结晶二维导热数学模型，计算了在下沉拉坯状态下结晶器铜版的温度场及铸坯发生拉时结晶器温度场的变化，通过对粘结型漏钢过程的模拟和拉时结晶器温场的分析，提出了对粘结型拉漏进行预报的预测参数。     

连铸板坯宏观偏析的研究

采用定量金相法了连铸板坯的溶质分布，应用水力学模型方法测定了板坯连铸结晶器内流场结构及流速，运用流体力学，溶质分配理论建立了凝固过程中溶质偏析模型，对铸坯宏观偏析进行了解析。R     

连铸结晶器弯月面区温度波动的模拟研究

作者设计了连铸结晶器弯月面处传热模拟实验 ,并测量了在结晶器振动情况下弯月面处的温度 ,发现该温度随着结晶器的振动而产生周期性的变化 .基于这种温度波动现象 ,讨论了包括热顶结晶器、高频小振幅振动、软接触结晶器电磁连铸等诸多技术改善铸坯质量的机理     

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…     

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

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.     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.