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1.
论术采用直流磁控溅射法制备TiO2薄膜的实验研究。研究了氧流量、基片温度对制备TiO2薄膜的影响,并测量了薄膜的晶相结构和表面形貌,结果表明制备出了具有锐钛矿晶体结构的TiO2薄膜.  相似文献   

2.
磁控溅射制备TiO2光催化薄膜工艺条件的优化   总被引:1,自引:0,他引:1  
常铁军  武秀芳  孙杰  孙艳 《应用科技》2007,34(1):66-68,72
采用正交实验设计法优化了玻璃基片表面磁控溅射制备TiO2光催化活性薄膜的工艺条件,以罗丹明B的降解率作为薄膜光催化性的评价标准.结果表明:所考察的因素对薄膜光催化性能的影响次序是靶基距〉基片温度〉溅射气压〉溅射功率〉氧氩比和靶基距的交互作用〉氧氩比;所得优化条件为:功率155W,靶基距85mm,气压1.2Pa,氧氩比1:10,基片温度550℃.  相似文献   

3.
通过射频磁控溅射的方法,分别在NaCl和Si基片上制备厚度约为10nm的ZnO薄膜,通过SEM、TEM等测试手段分析了薄膜的表面状况,结果显示,在两种基片上沉积的薄膜都呈现分形生长的形貌.通过对两种基片上生长的薄膜进行比较,分别计算了这两种薄膜的分形维数.在Al2O3上制备了厚度约为300nm的ZnO薄膜,通过在不同温度下对样品进行退火处理,并利用XRD、PL测试手段研究了退火处理对薄膜结构和光致发光性质的影响.结果表明,随着退火温度升高,薄膜的晶体结构逐渐变好,发光峰位也随着退火温度发生偏移.  相似文献   

4.
TiO2薄膜的光催化特性   总被引:12,自引:2,他引:12  
低压利用四异丙醇钛水解法制备了TiO2薄膜,将TiO2固定化并尽可能保留其尺寸效应,联系制膜条件和膜的表性,研究了TiO2薄膜的光催化活性,利用Raman,XRD,AFM和UVvis等手段探讨了不同膜厚,晶型,衬底对膜催化活性的影响,结果表明,随着衬底温度的升高,TiO2由非晶型转变为锐钛矿,光催化活性提高,随着TiO2薄膜厚度的增加,催化活性降低,在玻片,Si,SnO2,Al为基片所制TiO2薄膜中,以Al为基片的TiO2薄膜的光催化活性最好。  相似文献   

5.
热处理对溶胶—凝胶TiO2薄膜的特性影响   总被引:5,自引:1,他引:4  
研究了热处理对溶胶-凝胶法制备的TiO2薄膜材料的晶体结构、致密化以及光学特性的影响,结果表明TiO2溶胶颗粒的最低结晶化温度为400℃,晶体尺寸随着热处理温度的升高而增大;TiO2薄膜的厚度随着热处理温度的升高从120nm减小到47nm,相应的折射率则从1.85增加到2.3;同时,TiO2薄膜的孔洞率随着热处理温度的升高0.23降低到0.122,密度则从2.83g.cm^-3增加到3.73g.cm^-3。  相似文献   

6.
低压下利用四异丙醇钛水解法制备了TiO2薄膜,将TiO2固定化并尽可能保留其尺寸效应 .联系制膜条件和膜的表性,研究了TiO2薄膜的光催化活性.利用Raman、XRD、AFM和UV -vis等手段探讨了不同膜厚、晶型、衬底对膜催化活性的影响.结果表明,随着衬底温度的升高,TiO2由非晶型转变为锐钛矿,光催化活性提高;随着TiO2薄膜厚度的增加,催化活性降低.在玻片、Si、SnO2、Al为基片所制TiO2薄膜中,以Al为基片的TiO2薄膜的光催化活性最好.  相似文献   

7.
用MOCVD法制备TiO2薄膜   总被引:4,自引:0,他引:4  
用低压MOCVD法,以四异丙纯钛为源物质,高纯氮气作为载气,氧气为反应气体,制备出了TiO2薄膜,考察出了沉积温度,基片距离均对沉积速率有影响,发现在不同反应条件下TiO2薄膜生长行为受动力学控制或受扩散控制。  相似文献   

8.
以镓钛共掺杂氧化锌(GTZO)陶瓷靶作为溅射源材料,采用射频磁控溅射技术在玻璃基片上制备了GTZO透明导电薄膜,通过X射线衍射仪(XRD)、可见-紫外光分光光度计和四探针仪等测试表征,研究了基片温度对GTZO薄膜晶体结构、电学性质和光学性能的影响.结果表明:所制备的GTZO薄膜均为六角纤锌矿结构,并具有(002)择优取向,其结晶质量、晶粒尺寸、方块电阻、透过率、光学能隙以及品质因数都与基片温度密切相关,当基片温度为350℃时,GTZO薄膜的品质因数最大,具有最佳的光电综合性能.  相似文献   

9.
以醋酸盐和钛酸四丁酯为原料,采用溶胶-凝胶工艺在Pt/TiO2/SiO2/Si基片上制备了掺锰Ba0.5Sr0.5TiO3薄膜。通过X射线衍射和扫描电镜分析研究了薄膜的相结构和形貌,测试了以Pt为底电极、Ag为上电极的MFM电容器的介电性能。研究结果表明:掺锰Ba0.5Sr0.5TiO3薄膜较未掺杂的Ba0.5Sr0.5TiO3薄膜介电常数高、介电损耗降低。介温谱表明在居里温度附近发生弥散型相变,且居里温度有向低温方向漂移的趋势。  相似文献   

10.
采用溶胶凝胶法制备具有不同晶体结构的TiO2薄膜,研究了环境湿度、基体材料和催化剂酸种类等条件对薄膜质量(如完整性和晶体结构的单一性等)的影响,并在优化后的工艺条件下分别制备出了具有单一锐钛矿相和单一金红石相的均匀致密的纳米晶TiO2薄膜,结合表面能测试和红外光谱分析研究了两种不同晶体结构的TiO2的表面性能,结果发现锐钛矿型TiO2和金红石型TiO2表面都能捕获 OH基团,锐钛矿型TiO2表面有更多的 OH基团,表面能更高,表面亲水性更好.   相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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。  相似文献   

15.
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  相似文献   

16.
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  相似文献   

17.
18.
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.  相似文献   

19.
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).  相似文献   

20.
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.  相似文献   

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