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1.
通过对活性炭纤维(ACF)进行热处理和氧化改性得到具有不同比表面积、孔结构以及含氧官能团的ACF样品,并对这一系列样品进行甲醛吸附研究。实验结果表明,沥青基活性炭纤维(P-ACF) OG-5A具有最小的比表面积和孔容,具有最大的甲醛穿透容量。通过回归分析表明,ACF样品的甲醛穿透容量主要由孔径为0.9~1.8 nm的孔的比表面积和孔容来决定,而不是取决于总比表面积和总孔容。P-ACF OG-7A的氧化改性显著提高了样品的甲醛吸附能力,其中浓HNO_3改性后提升效果最为明显,改性后穿透容量为58.21 mg/g,是未改性样品穿透容量的2.5倍。氧化改性ACF表面含氧量的增加使得甲醛吸附能力增强,进一步通过Boehm滴定实验和回归分析表明酸性含氧官能团(酚羟基、内酯基、羧基等)数量的增加是ACF样品甲醛吸附能力提升的主要原因。酸性含氧官能团富含C=O、C-OH等亲水基团,对甲醛的吸附十分有利。  相似文献   

2.
文章系统阐述了活性炭纤维(ACF)表面功能的设计和控制方法,介绍了ACF的比表面积、孔径分布、表面化学结构与吸附对象的关系;从ACF表面物理、化学结构的可设计化入手,全面阐述了ACF物理结构的设计和控制方法及表面化学的改性方法;并介绍了其应用效果。  相似文献   

3.
活性炭纤维的表面功能设计和控制(Ⅱ)   总被引:2,自引:0,他引:2  
章系统阐述了活性炭纤维(ACF)表面功能的设计和控制方法,介绍了ACF的比表面积、孔径分布、表面化学结构与吸附对象的关系;从ACF表面物理、化学结构的可设计化入手,全面阐述了ACF物理结构的设计和控制方法及表面化学的改性方法;并介绍了其应用效果。  相似文献   

4.
湿氧化改性多孔炭对低浓度苯和丁酮蒸汽的吸附   总被引:22,自引:1,他引:21  
空气中挥发性有机化合物 (VOC)严重危害人体的身体健康 ,因而研究 VOC的去除具有重要意义。该文研究了椰壳活性炭 (AC)和粘胶基活性炭纤维 (ACF)湿氧化处理后对低浓度 VOC苯和丁酮的吸附。 AC和 ACF分别用质量分数为 30 %和 5 0 %的 H2 O2 、浓 HNO3进行湿氧化处理。采用 X射线光电子能谱 (XPS)和氮气容量法研究了 ACF,采用扫描电镜 (SEM)研究了 AC处理前后性质的变化。并利用热重分析仪 (TGA)研究了对挥发性有机化合物丁酮和苯的吸附。实验结果表明 :ACF经 H2 O2 处理后具有活化作用 ,比表面积和微孔容积都增加了 ,特别是用质量分数为 30 %的 H2 O2 处理后更有利于低浓度苯和丁酮的吸附 ;AC经湿氧化处理后 ,扫描电镜下呈现不同的微观形貌特征 ,质量分数为 30 %的 H2 O2 处理后 ,增强了对苯的吸附 ,减弱了对丁酮的吸附。  相似文献   

5.
采用溶胶-凝胶法,将脱硫多官能团薄膜负载在聚丙烯腈基活性炭纤维(ACF)上,并进行持续动态吸附和百次再生.通过实验研究分析,脱硫多官能团是以薄膜形式均匀包覆在ACF的纤维表面,脱硫多官能团薄膜封堵ACF纤维表面的部分孔洞,造成样品负载脱硫官能团ACF的比表面积、孔容和饱和吸附量都要略小于ACF,但对于硫化物的指向性和吸附量反而增大;百次反洗再生后,包覆在ACF纤维上的脱硫官能团薄膜会有一定程度的开裂翘起,使原本被封堵的孔隙结构重新露出,提高了样品比表面积、孔容和饱和吸附量.经过预膜剂原位再生后,包覆在ACF纤维上的脱硫官能团薄膜被重新修补如初.在臭氧的作用下,除了能够转化硫化物的吸附形态,还会对载体ACF产生再生自洁作用,使ACF吸附作用的时间大大延长.  相似文献   

6.
介绍了用粘胶纤维毡在真空设备中经碳化活化工艺制备活性碳纤维 (ACF)毡的研究工作。论述了制备粘胶基 ACF毡适用的预处理介质、碳化活化原理以及工艺参数的确定 ;给出了 X射线衍射对ACF毡晶体结构分析结果。工艺试验表明 ,用真空设备制备高性能ACF切实可行。  相似文献   

7.
活性炭纤维的表面功能设计和控制(Ⅱ)   总被引:1,自引:0,他引:1  
文章系统阐述了活性炭纤维(ACF)表面功能的设计和控制方法,介绍了ACF的比表面积、孔径分布、表面化学结构与吸附对象的关系;从ACF表面物理、化学结构的可设计化入手,全面阐述了ACF物理结构的设计和控制方法及表面化学的改性方法;并介绍了其应用效果。  相似文献   

8.
活性炭纤维的表面功能设计和控制(Ⅰ)   总被引:1,自引:0,他引:1  
文章系统阐述了活性炭纤维 (ACF)表面功能的设计和控制方法 ,介绍了ACF的比表面积、孔径分布、表面化学结构与吸附对象的关系;从ACF表面物理、化学结构的可设计化入手 ,全面阐述了ACF物理结构的设计和控制方法及表面化学的改性方法;并介绍了其应用效果  相似文献   

9.
以钛酸丁酯为前驱体,采用溶胶-凝胶法制备了Fe、N离子共掺杂的、以活性炭(AC)和活性炭纤维(ACF)为载体的TiO2/AC和TiO2/ACF光催化剂.采用扫描电镜、X射线衍射仪、紫外-可见光分光光度计等对催化剂样品进行了表征.选取甲苯为模型化合物进行光催化降解实验,研究了催化剂制备过程中离子掺杂量、抑制剂种类、焙烧温度、载体种类以及循环使用次数对催化剂活性的影响.结果表明:TiO2在ACF上的分散效果好于在AC上;TiO2以颗粒状镶嵌在AC孔隙内、以膜状包覆在ACF表面,所制备的光催化剂均以锐钛矿相存在;Fe、N离子共掺杂实现了催化剂的可见光响应;以冰醋酸为抑制剂、N和Fe离子掺杂量均为8%(摩尔分数)、500℃下焙烧2 h时,所得的TiO2/ACF光催化剂对气相甲苯的降解活性最高,循环使用效果最好.  相似文献   

10.
活性炭纤维脱硫性能研究   总被引:2,自引:0,他引:2  
结合仪器分析与吸附模型分析了活性炭纤维(ACF)和颗粒状活性炭(GAC)的孔与表面特性,在不同工况下进行了ACF和GAC的脱硫实验.结合经典的吸附理论和实验结果论讨论了影响ACF和GAC脱硫性能的因素,在大量实验数据和数据分析的基础上,比较了活性炭纤维和传统的颗粒状活性炭的脱硫性能,得出ACF的动态脱硫性能明显好于GAC的结论.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
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   

18.
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   

19.
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   

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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