新型明胶基碳纳米管骨架活性炭的制备

催化裂解法制备的碳纳米管(CNTs)经混酸纯化后,均匀分散到明胶的溶液中,用乙醇析出得到明胶/碳纳米管海绵前驱体,再通过炭化、氢氧化钾活化处理制备出明胶基碳纳米管骨架活性炭.采用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对样品的表面形貌进行表征,结果显示:碳纳米管能够很好地被明胶包覆,并均匀分散在整个基体中.比表面和孔结构测试结果表明:随着碳纳米管含量的增大,活性炭样品比表面积和总孔容先增大后减小.此外,还对明胶基碳纳米管骨架活性炭孔结构的形成机理进行了分析讨论.     

单壁碳纳米管的制备和纯化研究

采用双金属Eu/Ni做为催化剂,用直流电弧放电法制备单壁碳纳米管(single walled carbon nanotubes, SWNTs),并对其进行了纯化处理.利用扫描电子显微镜、透射电子显微镜和拉曼光谱对所得样品进行了表征.结果表明,以双金属Eu/Ni为催化剂与Y/Ni为催化剂合成的单壁碳纳米管直径分布相近,其中1.36 nm为直径的碳纳米管占多数.经纯化处理的单壁碳纳米管有较高的纯度.     

化学气相沉积法制备碳纳米管及场发射性质的研究

讨论了化学气相沉积法制备碳纳米管的方法及过程,通过扫描电子显微镜(SEM)和透射电子显微镜(TEM)发现制备的碳纳米管的外直径在30-100nm之间;在10-5Pa高真空的条件下测定了碳纳米管薄膜的场发射性质,并比较了样品的老炼过程对场发射性质的影响.     

碳纳米管／Mo复合粉末的制备

[摘要]以仲钼酸铵为前驱物,采用溶胶一凝胶法和氢气还原工艺制备了碳纳米管／Mo复合粉末材料．采用扫描电子显微镜（SEM）和x射线衍射（XRD）分析了微观形貌和相态组成．结果表明：在750℃还原保温3h可制备出碳纳米管／Mo复合粉末,还原生成的Mo粉颗粒在碳纳米管周围聚集,使碳纳米管在Mo粉中均匀分散;高于800℃还原,碳纳米管与Mo反应生成M02C相;而低于750℃还原,则有MoO2相残存．     

在多孔Al2O3膜板上制备取向碳纳米管

在阳极氧化法制备的多孔Al2O3膜板上用CⅧ技术制备出了大面积且高度取向的碳纳米管及阵列,用透射电镜(TEM)和扫描电镜(SEM)观察了碳纳米管阵列的表面形貌和单根碳纳米管的精细结构．分析了不同沉积条件对碳纳米管及阵列生长特性的影响．结果表明,阳极氧化法制备的Al2O3多孔膜板的高取向性使沉积生长其中的碳纳米管阵列也具有极佳的取向性和可控性．     

单壁碳纳米管的超导电性

阐述了电弧法制备单壁碳纳米管以及在单壁碳纳米管内实现超导态的实验方法。对用电弧法制备碳纳米管的实验条件、实验过程和实验产物进行了讨论。此外，分析了用、接受诱导法”实现碳纳米管的超导电态的具体条件，即将单壁碳纳米管束或单个碳纳米管嵌放在两个超导电极之间，在一定的条件下，有可能在碳纳米管内诱导出超导电流，已有的实验显示碳纳米管内的超导电流的临界值较大，并表现出特殊的对温度和磁场的依赖性。“接近诱导法”打开了探索碳纳米管超导性质的大门。     

浮动催化裂解法制备碳纳米管的副产物

研究了浮动催化裂解法制备碳纳米管过程中所生成的副产物(碳纳米球、Y型连接碳纳米管和碳纳米管薄膜)的形态及成因,使用透射电子显微镜(TEM)及Raman光谱对产物进行了检测。结果表明,碳纳米球在石墨化后进一步转化为晶化程度较好的纳米晶球;Y型连接碳纳米管及碳纳米管薄膜的产生是由浮动催化法自身特点所决定的;通过控制工艺参数可以实现这些副产物的半连续制备。     

碳纳米管的提纯及表征

为了获得高纯碳纳米管,对用电弧催化法合成的碳纳米管粗产物进行了纯化处理.根据阳极电弧催化法制备碳纳米管的3种产物(网状物、膜状物和棒状物)的杂质性质和特点,用微孔膜、甲苯萃取,浓盐酸酸洗、混酸氧化和空气氧化法分别对3种产物采用选择性清除法去除杂质,得到了质量分数在90%以上的单壁碳纳米管.并利用透射电子显微镜(TEM)、热重分析(TGA)和拉曼(Raman)光谱等手段对提纯的碳纳米管进行观察、分析和表征.结果显示,该提纯方法比其它方法回收率高,纯度高,氧化条件柔和,实验过程易于控制.     

PECVD技术制备碳纳米管的研究

碳纳米管的制备方法有电弧法、激光蒸发法、化学气相沉积法(CVD法)、火焰法、水热法和模板法等.主要介绍了等离子体化学气相沉积法制备碳纳米管,并对此方法制备的碳纳米管形貌进行了表征,最终优化出最佳的实验工艺.     

以MnCl_2为催化剂前体用CVD法合成碳纳米管

以MnCl2为催化剂前体,利用化学气相沉积法合成出了碳纳米管,利用电子显微镜和能量色散X射线谱对样品进行了表征,系统研究了碳纳米管生成的条件。     

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.