熔融盐法制备CuCl2-石墨层间化合物及形成机理

通过熔融盐法制备CuCl_2插层的石墨层间化合物(CuCl_2-GICs),探讨了加热时间、反应物配比对CuCl_2-GIC产物的阶结构、表面形貌及导电性的影响.结果表明,产物含有主阶为1阶的混阶石墨层间化合物和一定量的石墨;延长反应时间有助于增强插层效果;反应物配比对产物的阶结构组成影响较小.插层后的石墨发生了膨胀,在片层的边缘分布着较多的CuCl_2颗粒;制备的CuCl_2-GICs中CuCl_2为非化学计量比,其中[Cl~-]离子不足.CuCl_2-GICs的电导率较石墨原料有所提升,最大提升80%.     

水下电弧放电法制备NiCl_2-石墨插层化合物的研究

首次提出采用水下电弧放电法一步合成氯化镍石墨插层化合物(NiCl2-GICs)。合成插层化合物所用的母材为光谱纯石墨棒,插层剂为NiCl2。运用X射线衍射(XRD)分析和表征了6阶NiCl2-GICs的结构。通过X光电子散射(XPS)对NiCl2-GICs的研究发现其结合能发生了变化,表明在NiCl2和石墨中存在着电子的授受行为,并且Cl原子和C原子之间存在一定的键合作用。据此可以推测,NiCl2-GICs中与碳原子层最靠近的插层原子为Cl原子。研究结果表明,对NiCl2-GICs来说,这是一种简单可控的合成方法。     

三元石墨插层化合物的合成与表征

采用混合熔盐法，以CuCl2，FeCl3为客体材料，粒径1—10μm天然鳞片石墨为主体材料，合成出2，3阶结构的三元石墨层间化合物CuCl2—FeCl3—GICs．简述其制备工艺，应用XRD，SEM，EDS对产物的晶体结构、表面形貌及元素组成进行测试表征，并检测和分析其电磁传导性能．测试结果表明CuCl2—FeCl3—GICs是一种新型轻质导电材料．     

石墨结构层包覆铁镍纳米粒子的电学及磁学性能表征

用金属钾还原不同阶结构的FeCl3-NiCl2石墨层间化合物前驱体制备了石墨结构层包覆铁镍纳米粒子材料（GEINP）。用四端电极法表征了样品常温电阻率以及电阻率随温度的变化规律,用古埃磁天平法测定了样品的磁化率。结果表明,GEINP电阻率高于原料石墨,呈半导体导电特征,表现为弱磁性,磁化率为10^-2量级。     

3-巯基丙酸稳定的CdSe量子点的制备及其荧光性能

以CdCl₂·2.5H₂O,Na₂SeO₃和NaBH₄为反应物,制备3-巯基丙酸稳定的CdSe量子点.研究了加热回流时间、镉和硒的物质的量及镉和3-巯基丙酸的物质的量之比等实验条件对CdSe量子点光谱性能的影响.采用紫外-可见光谱、荧光光谱、X射线粉末衍射和高分辨透射电镜等分析手段,对量子点的光学性能和结构进行表征.结果表明,反应时间、镉和硒的物质的量及镉和3-巯基丙酸的物质的量之比等实验条件对CdSe量子点的光谱性能有明显影响;不同条件下制备的量子点的荧光发射峰的半峰宽保持在35~40 nm范围内;所得CdSe量子点为立方晶型.在pH值为11.0,且nCd∶nSe∶nMPA=1∶0.2∶1.1的条件下,回流90 min制备的量子点的荧光量子产率值可达16.1%.     

一步法回收锂离子电池三元正极材料及其性能影响

采用直接一步法回收废旧锂离子电池中的三元正极材料LiNi_0.5Co_0.2Mn_0.3O₂,将拆解得到的三元废料经分离、热解处理后进行酸浸,对酸浸溶液进行元素测定后补加Ni、Co、Mn源,使其物质的量之比符合n(Ni)∶n(Co)∶n(Mn)=5∶2∶3. 调整后的溶液直接与草酸钠溶液进行共沉淀,得到草酸盐前驱体,最后与锂源混合,烧结得到三元再生正极材料. 结果表明:再生正极材料的首次放电容量最高达162 mAh/g,充放电100次后的容量保持率接近88%. 但如果材料中杂质元素含量过高,则会对材料电化学性能造成负面影响. 该方法避免了传统方法中将金属元素逐一分离回收所造成的资源浪费和能源损耗,且制备得到的材料具有较高附加值,具有良好的商业化应用前景.     

硫酸铁铵催化合成丁酮乙二醇缩酮

以乙二醇和丁酮为原料,NH4Fe（SO4）2.12H2O为催化剂合成丁酮乙二醇缩酮。通过正交实验得出的适宜反应条件为：固定丁酮的物质的量0.2mol,丁酮与乙二醇的物质的量之比为1.0∶1.6,NH4Fe（SO4）2.12H2O用量占反应物总量的4.3%,反应时间为2.5h,带水剂环己烷用量20mL.在此反应条件下,丁酮乙二醇缩酮的收率为68.1%.     

γ-Fe(111)，Co(0001)，Ni(111)，C(0001)晶面电子密度计算及触媒作用优劣的价电子结构分析

由于Fe,Co,Ni元素密集面上的原子与石墨层面上单号原子间距相近,常用作触媒,使石墨在较低压力和温度下直接转化为金刚石,异相界面上电子密度的大小和差异直接影响其结合能力.笔者应用余瑞璜教授的固体与分子经验电子理论,对Fe,Co,Ni,C的价电子结构进行了键距差(BLD)分析,发现γ-Fe处于B种杂化第12阶, Co 在第12 阶,Ni在第10 阶,C在第6 阶.计算出γ-Fe(111),Co(0001),Ni(111),C(0001)晶面的平均共价电子密度(简称电子密度)分别为38.272 8 nm - 2,54.603 5 nm - 2,54.766 6 nm - 2,76.334 0 nm - 2.作为触媒,Co 和Ni优于Fe.     

超声波辅助水热合成条件对Fe3O4纳米微粒生长及磁性的影响

以FeCl3.6H2O,FeCl2.4H2O和NH3.H2O为原料,在超声波辅助下,用水热法合成了纳米磁性Fe3O4粒子,借助X射线衍射仪（XRD）、透射电镜（TEM）仪及振动样品磁强计（VSM）对产物Fe3O4进行分析,结果表明,当反应物物质的量之比（n（Fe^3＋）/n（Fe^2＋））为1.75,pH=13得到的前驱物,控制水热合成温度为140-160℃,水热处理时间为3-5 h时,可制备出纯相的反尖晶石结构的Fe3O4纳米微粒,随着水热合成温度的升高和时间的延长晶体发育越完整,平均粒径越大.磁性测量表明,饱和磁化强度和矫顽力也随着Fe3O4纳米微粒平均粒径的增大而增大.     

氯乙酸乙酯的合成研究

目的以自制的复合无机盐Fe2（SO4）3.Na2S2O8为催化剂,氯乙酸和乙醇为原料合成氯乙酸乙酯.方法研究了氯乙酸与乙醇的摩尔比、催化剂用量、环己烷的用量、反应时间等因素对产品收率的影响,并用红外光谱（IR）、元素分析对产物氯乙酸乙酯进行了表征.结果与结论复合无机盐Fe2（SO4）3.Na2S2O8是合成氯乙酸乙酯的良好催化剂,适宜的反应条件如下：氯乙酸与乙醇的摩尔比为1∶2.0,催化剂用量为反应物总质量的2.5%,环己烷用量12 mL,反应时间1.5 h,氯乙酸乙酯的收率可达85.61%.     

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.