等离子氮化处理改善铁的耐腐蚀性能研究

通过电化学测试方法对等离子氮化处理前后铁的耐腐蚀性进行研究.采用扫描电子显微镜(SEM)对极化试验后样品表面的腐蚀形貌进行观察.结果表明,等离子氮化处理后的样品的蚀孔数量少,其腐蚀程度明显优于未经处理的样品.应用X射线衍射(XRD)及X射线光电子能谱(XPS)分析其腐蚀机理.结果证实,等离子氮化处理后铁的耐腐蚀性能得以改善,归因于材料表面形成的铁氮及铁氧结合层.     

铝合金表面红色Ce-Se化学转化膜成分与耐蚀性研究

本文在室温条件下用铈盐和硒化物作为主盐,在铝合金表面制备了一种新型有色铈硒化学转化膜。利用电化学工作站测试了转化膜的极化曲线、阻抗谱;用扫描电子显微镜(SEM)、能谱分析(EDS)和X射线光电子能谱分析(XPS)等观察分析了转化膜的表面形貌、成分与结构。结果表明,铝合金经Ce-Se化学转化膜处理后,其极化电阻较空白铝合金有较大幅度的提升,自腐蚀电流降低了一个数量级,自腐蚀电压正移,铝合金的耐蚀性能得到显著的提升;扫描电子显微镜(SEM)观察表明,该转化膜层具有良好的连续性,表面有微凹与微凸起伏,且带有圆球形颗粒;通过能谱(EDS)和X射线光电子能谱分析(XPS)表明,铝合金Ce-Se转化膜的主要组成元素有Se、Ce、O、F、Na、Mg、C等。     

SiC表面负载Cu复合材料的制备与表征

基于工业碳化硅(SiC)微粉,采用化学改性法将铜负载于SiC原粉表面,使用扫描电子显微镜(SEM)、X-射线粉末衍射仪(XRD)和X-射线光电子能谱(XPS)等表征测试方法,分别考察了pH值、Cu负载量、分散介质等因素对改性实验的影响.结果显示:经高温煅烧后,Cu离子以CuO和Cu2O的氧化态形式负载于SiC表面;不同的分散介质、pH值和Cu离子负载量影响以氧化态形式负载到SiC表面的Cu离子分布.     

微弧氧化对7050铝合金腐蚀行为的影响

采用微弧氧化(MAO)技术在7050铝合金表面制备了陶瓷膜层,运用扫描电子显微镜(SEM)和能谱分析仪(EDS)表征陶瓷膜微观结构,采用动电位极化曲线、电化学阻抗谱(EIS)和慢应变速率拉伸试验(SSRT)研究了微弧氧化膜对7050铝合金在3.5%(质量分数)NaCl水溶液中腐蚀和应力腐蚀开裂(SCC)行为的影响.结果表明:微弧氧化膜层由表面疏松层与内部致密层组成,表面疏松层主要由Al2O3组成,内部致密层由氧化铝与铝烧结而成.微弧氧化膜层可以有效抑制7050铝合金表面的腐蚀萌生及明显降低腐蚀速率,且使7050铝合金的应力腐蚀敏感性出现显著下降.     

浓硫酸氧化改性天然辉钼矿及其电催化性能研究

用浓硫酸加热氧化法, 获得提纯的辉钼矿。利用 X 射线荧光光谱(XRF)、X 射线衍射(XRD)、X 射线光电子能谱(XPS)、扫描电子显微镜(SEM)和拉曼光谱(Raman), 对氧化前后的样品进行表征, 并测试样品的电催化性能。经浓硫酸氧化后, MoS₂的(002)晶面晶粒的平均粒径减小14%, 层间距增加0.04 Å, 且S²⁻被氧化为S⁶⁺。结果表明, 经过浓硫酸氧化, MoS₂的片层能够在一定程度上被剥离, 辉钼矿对于对硝基苯酚的还原作用增强, 还原峰电位发生正向移动。     

离子镀氮化钛膜层综合剖析

本文应 X 用射线光电子能谱(XPS)、俄歇电子能谱(AES)、X 射线衍射(XRD)等技术,对用空心阴极离子镀法(HCD)生长的氮化钛膜层作了综合测试,对膜层的组分和结构作了分析,着重论述了外表面氧化膜及界面过渡层的产生和作用。由 XRD 分析得知,氮化钛晶粒中与衬底有良好共格关系的那些晶面平行于膜面生长。     

十二羟基硬脂酸的醇溶液浸泡金属片引发的超疏水性

通过十二羟基硬脂酸的醇溶液浸泡,在铁、锌、铜锌合金的表面进行氧化还原自组装反应,形成了微纳米结构的粗糙表面超疏水结构,静态水接触角超过160°,讨论了可能的生成机理.利用X射线光电子能谱(XPS)、接触角测量、红外光谱(IR)、扫描电子显微镜(SEM)进行表征.结果表明,构筑的金属表面结构具有良好的超疏水性.     

常压射频放电占空比对SiO_x薄膜形貌和成分的影响

采用常压射频等离子体放电技术,以六甲基二硅氧烷(HMDSO)和Ar的混合气体为反应源,成功制备了SiO_x薄膜.通过测量放电的电流-电压曲线以及发射光谱,研究不同占空比对射频放电段放电特性的影响;利用扫描电子显微镜(SEM)、X射线能谱仪(EDS)以及X射线光电子能谱(XPS)研究了不同占空比放电条件下沉积的SiO_x薄膜的表面形貌与化学成分.研究结果表明,占空比对射频放电段的放电特性影响不大,但是随着放电脉冲占空比的增加,薄膜表面变得不平滑,椭球形颗粒增多,薄膜中无机成分也相应增加.     

钛表面微弧氧化羟基磷灰石陶瓷膜的结构及其生物活性

采用微弧氧化技术(MAO),以纯钛(TA2)为基体,在醋酸钙和磷酸二氢钠电解液体系中,制备含羟基磷灰石(HA)的生物活性陶瓷膜,并利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线能谱(EDS)和红外光谱(FT-IR)对膜层进行表征,通过体外模拟体液浸泡实验检测膜层的生物活性.结果表明,纯钛经微弧氧化处理10min后,在其表面能生成一层含羟基磷灰石成分的多孔陶瓷膜,该膜层经模拟体液浸泡48h后,其表面覆盖一层含有CO2-3的羟基磷灰石(类骨磷灰石),即该陶瓷膜层具有良好的生物活性.     

氧化锌超微粒子薄膜的表面性质研究

用直流气体放电活化反应沉积的方法,制备了氧化锌超微粒子薄膜,并经AES成分分析及XRD物相结构鉴定,随制备条件不同,结构将明显改变。扫描电子显微镜(SEM)分析结果表明,粒子的粒径为88.5nm。用俄歇电子能谱(AES)、X射线光电子能谱(XPS)对超微柱子膜的表面成分此、表面电子态进行了研究,用Ar~+枪对样品表面进行了剥离,同时用AES作跟踪分析。结果表明,Zn/O比基本保持不变,C稍有减少。这和电子探针持续作用AES跟踪分析结果基本相同。样品表面的电子态是Zn2p_(1/2)、Zn2p_(3/2),Cls、Ols;粒径及基质对表面光电压谱有较大影响。     

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.