铝电解用Fe-Ni-Co-Al-2O3金属陶瓷惰性阳极

研制了一种新型铝电解金属陶瓷惰性阳极，阳极基体由Fe-Ni-CoAl2O3构成。在石墨坩埚中，960℃温度下，电解质中的氧化铝质量分数为60%，摩尔比为26；阳极电流密度为10 A/cm2，阳极尺寸大小为120 mm×80 mm×15 mm，石墨阴极尺寸大小为120 mm×40 mm×20 mm，通入的直流电为100～300 A，电解时间各为10 h；实验所得的电解铝产品纯度达到98%以上，杂质主要为Fe，Ni，Co；电解后的阳极外观尺寸无明显变化，阳极气体中氧气质量分数达到98%～99%。阳极的反电动势为245 V，比理论分解电压仅高出025 V证明该阳极为惰性阳极，在电解槽中进行的是Al2O3的分解反应。     

采用软化学法制备WO3和其锂化物及其结构稳定性的研究

通过两种方法合成了六方形和单斜氧化钨的水化物WO3·yH2O(y=0.50～1.20):(1) 用强酸(1～3 mol/L HCl) 将0.25 mol/L Li2WO4在100 ℃进行酸化; (2) 将1 mol/L Li2WO4置于高压反应釜中,控制pH为1.5,在100 ℃进行水热合成. 对于水热法,温度较高时(125～200℃),得到组分为LixWO3+x/2·yH2O(x=0.10～0.50,y=0.50～0.90)的锂化氧化钨. 合成产物的结构和组分与酸的浓度和后处理(加热、超声波)有关. 在350 ℃加热时六方形氧化钨完全转化为单斜氧化钨. 将温度在150 ℃以上时通过水热法合成的氧化钨前驱体进行超声波处理,产物的含锂量恒定为每单元0.18摩尔. 锂的引入有利于锂化氧化钨的结构和组分的稳定.     

0Cr19Ni9 1Cr18Ni9不锈钢薄壁焊管缺陷及对策

南京某厂从日本引进焊管机组,用带式法生产薄壁不锈钢管。其工艺流程如下: 钢带分剪→轧辊成型→钨极氩弧焊(TIG)焊成管坯→冷拔→矫直→成品。采用某厂一批0.3mm厚的1Cr18Ni9和0Cr19Ni9奥氏体不锈钢带试焊,发现有焊渣间隔分布于焊缝的内外壁上。间隔距离从5mm至100mm不等,大部分在20～30mm之间,见图1.焊渣多呈灰褐色,其形如纺锤状,尺寸(长×宽)约在(10～20)mm×(4～6)mm。     

硫铁矿烧渣水热法合成形貌可控的氧化铁

以硫铁矿烧渣硫酸浸出液与氨水反应制备的Fe(OH)3胶体为前驱体,采用水热法合成不同形貌的氧化铁粒子。在中性介质中考察反应温度、物质的量比(n(Fe2+)/n(Fe3+))、水热体系总Fe浓度及晶种量对水热法氧化铁物相、形貌和粒径的影响。采用X线衍射仪、扫描电镜、透射电镜及选择区域电子衍射对水热产物物相和形貌进行研究。研究结果表明:反应温度为230℃,n(Fe2+)/n(Fe3+)为0.1以及水热体系总Fe浓度为1.25 mol/L和晶种量为2 g时,水热产物为片状α-Fe2O3粒子;控制上述其他条件不变,当温度在140～260℃时,随着温度的升高,水热法产物由α-FeOOH相向α-Fe2O3相转变,α-Fe2O3粒子形貌由球形向小圆饼状和片状依次转变;当n(Fe2+)/n(Fe3+)在0～0.12时,随着n(Fe2+)/n(Fe3+)的增加,水热产物由α-Fe2O3相向α-Fe2O3和Fe3O4相转变,α-Fe2O3粒子形貌由球形逐渐向片状转变,其粒径由小变大;当水热体系中总Fe浓度为0.625 mol/L和1.875 mol/L时,水热法氧化铁分别为不均一形貌和球形;当没有加入晶种及晶种量为6 g时,水热...     

掺钕钛酸铋纳米结构的水热合成研究

以Bi（NO3）3·5H2O,Nd（NO2）3·6H2O和Ti（OC4H9）4为原料,NaOH为矿化剂,采用水热法合成铋层状钙钛矿掺钕钛酸铋（Bi3.15Nd0.85Ti3O12,BNdT）纳米结构．利用X射线衍射（XRD）、扫描电子显微镜（SEM）表征产物的晶相和形貌．研究反应温度、矿化剂浓度和反应时间对水热合成BNdT纳米结构的影响．结果表明,在适当的水热反应条件下能有效合成BNdT纳米结构,在反应温度为150℃、175℃、200℃和220℃时分别形成球状、球状与片状共存、棒状和片状产物．     

新型VCOCXO控温原理及实现方法研究

提出了VCOCXO的一种新型控温方法 ,论述了其控温原理及实现 .从而研制成频率温度稳定度达到± 1× 10 -8( - 40～ 70℃ ) ,体积为 2 5mm× 2 5mm× 15mm的小型高稳恒温晶体振荡器     

催化光度法测定痕量Cr6+

根据pH值为5.0的HAc-NaAc溶液中,Cr6+催化H2O2氧化四氯四碘荧光索二钠的褪色反应,建立催化动力学光度法测定痕量Cr6+的新方法.新方法的检出限为1.05×10-9g/ml,测定线性范围为0～35μg/L Cr6+.新方法用于天然水中痕量Cr6+的测定,结果良好.     

含钛电炉熔分渣制备4A分子筛及其吸附性能

以含钛电炉熔分渣提钛后的水浸液为原料,采用常压回流法和水热法分别合成了4A分子筛.在控制硅铝比(n(SiO2)/n(Al2O3)摩尔比)为2的条件下,系统探讨了水钠比(n(H2O)/n(Na2O)摩尔比)、反应时间和温度对合成4A分子筛物相和微观形貌的影响.当控制水钠比为80且反应时间为8 h时,采用常压回流法可以制备出尺寸均一且结晶完全的4A分子筛;而采用水热法在120℃条件下,3 h即可制备得到形状规则的4A分子筛.另外,探讨了水热法不同反应温度条件下制备的分子筛对硫酸铜溶液吸附性能的影响.结果表明:反应温度为120℃条件下合成的4A分子筛对铜离子的吸附效率最高,在150 min时其吸附率可达70%.     

段状玉米秸秆阴燃特性试验研究

以北方高寒地区玉米秸秆为研究对象，利用正交设计的试验方法，选取颗粒尺寸、堆积尺寸、堆积密度以及含水率为影响因素，在自制的阴燃试验台进行北方高寒地区玉米段状秸秆的阴燃特性的研究.研究表明：秸秆尺寸350 mm、堆积尺寸250 mm×350 mm×300 mm、堆积密度40 kg/m3、含水率20%时，炉腔内温度高、阴燃时间最长，最高平均温度为701.6℃，阴燃时间为145 min；阴燃时阴燃波自上而下，温度的变化自上向下逐渐升高，属于正向阴燃.     

水热温度和pH值对合成纳米结构γ-AlOOH形态的影响

1mol/L的AlCl₃溶液为铝源,1mol/L的NaOH溶液为沉淀剂,在水热法反应体系中研究了温度和pH值对合成纳米结构γ-AlOOH形态的影响。利用X射线衍射仪(XRD)和热场发射透射电子显微镜(FETEM)对合成的样品进行表征。XRD分析表明不同水热条件下获得样品的物相为γ-AlOOH。FETEM分析显示在时间为48h和pH值为5时水热法合成γ-AlOOH时,在120℃下合成了径向分布不均匀的棒状γ-AlOOH;在150℃下获得了径向尺寸趋于均匀的棒状γ-AlOOH;在180℃下制备出了径向分布较均匀的约20nm的γ-AlOOH。但是,在210℃下合成的薄片状的γ-AlOOH。在温度为180℃和时间为48h时水热法合成γ-AlOOH时,当pH值由5增加到7时,合成γ-AlOOH的径向尺寸变小得不太明显;当pH值由7增加到9时,获得γ-AlOOH的径向尺寸显著的变小,其径向尺寸约为10nm。但是,当pH值为11时,制备出了细小薄片状的γ-AlOOH。最后,对水热法体系中温度和pH值对合成γ-AlOOH形态影响的机理进行了讨论。     

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.     

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.     

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).     

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.