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活性炭纤维研究与应用进展 总被引:8,自引:0,他引:8
活性炭纤维(ACF)是由有机纤维先驱体制得的一种理想的高效吸附材料。ACF以其特殊的表面化学结构和物理吸附特性广泛应用于环境保护、电子工业、化工、医疗卫生、低成本SiC纤维制备等领域。本文就ACF的结构与吸附特性、制备与应用等做了较系统的综述,并对其发展趋势做出了展望。 相似文献
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采用微波辐射法合成MIL-101多孔材料,探讨了反应温度对材料合成的影响。同时对MIL-101进行XRD测试以及孔结构和比表面积分析,采用重量法测定了288、298和308K条件下苯在MIL-101多孔材料上的吸附等温线,并估算MIL-101对苯的等量吸附热。结果表明,MIL-101多孔材料的比表面积达2089.2m2/g,苯在MIL-101上的吸附等温线呈I型等温线,与Langmuir模型吻合很好,表明吸附主要为微孔吸附;随着温度的升高,MIL-101对苯的平衡吸附量逐渐下降,说明苯在MIL-101多孔材料的吸附以物理吸附为主。在T=298K,p/p0=0.5时,苯在MIL-101多孔材料上的吸附量为9.44mmol/g,远高于同等条件下普通活性炭和活性炭纤维对苯的吸附容量;苯在MIL-101上的等量吸附热为45.4~41.6kJ/mol的范围,其等量吸附热随着表面吸附量的增加变化幅度不大,与活性炭纤维相比,MIL-101的表面吸附自由能分布比较均匀。 相似文献
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沥青基活性炭纤维的微孔性及其对NO,SO2和NH3的吸附特性 总被引:3,自引:0,他引:3
通过对新开发的沥青基活性炭纤维(ACF)在77K温度下对氮的吸附和303K温度下对苯的吸附研究,考察其微孔性。沥青基ACF具有均匀的微孔,孔径为0.9-1nm,孔体积为0.45-1.0ml/g。也考察了在303K温度下对NO、SO_2和NH_3的吸附行为。不仅对氮和苯而且对NO、SO_2和NH_3的吸附等温线进行了DR关联,作出关联图并讨论了微孔填充。微孔填充度按NO、NH_3、SO_2次序增大。每种气体微孔填充度和等量吸附热随这些被吸附气体的范德华(Van der Waals)力的增加而增加。 相似文献
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高比表面积PAN-ACF的吸附与孔结构解析 总被引:7,自引:0,他引:7
以KOH为活化剂制备了比表面积大于2000m^2/g的高比表面积PAN基活性炭毡(ACF),以液氦为吸附介质在77.4K测试PAN-ACF吸附等温线,并对其孔结构进行了表征。采用BET法计算比表面积,t-plot法,Horvath-Kawazoe,Dubinin-Radushkevich方程以及密度函数理论(DFT0表征孔结构。研究表明即使比表面积超过3000m^2/g时,PAN-ACF的孔分布仍然很窄,并且含有大量的分子筛型孔,以金子克美等人提出多段吸附机理为依据,采用DR方程对PAN-ACF三段吸附过程所对应的E^0,x进行了计算。结果认为低压段的负偏离在一定程度上是由于吸附较强的微孔与表面官能团共同作用的结果,并非完全由于活化扩散引起,以上分析方法的表征结果具有较好的一致性,为PAN-ACF的吸附性能与孔结构提供了准确的信息。 相似文献
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氨水改性活性炭纤维吸附苯乙烯的性能 总被引:5,自引:0,他引:5
主要研究采用氨水对活性炭纤维ACF表面进行改性,制备了3种不同的改性ACF,测定ACF孔结构和表面酸碱基团,并测定了苯乙烯在改性ACF床层的吸附透过曲线,讨论了改性ACF的孔结构和表面酸碱基团对其吸附性能的影响.结果表明,与原始ACF相比,经氨水改性后的活性炭纤维ACF其表面碱性基团含量、孔容及其比表面积增加,从而明显提高了对苯乙烯的吸附容量;用浓度为6mol/L的氨水改性的ACF2其微孔孔容及其比表面积最大,其对苯乙烯的吸附容量也最大. 相似文献
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采用硝酸对自制的沙柳活性炭纤维进行处理来制备改性吸附材,并与未改性活性炭纤维进行对比,借助红外光谱、扫描电镜等方法分析两者的性能及结构差异。在含铅污水的净化试验中,重点对比分析了水溶液pH值对吸附效果的影响,线性吸附等温线及吸附动力学模型拟合的差异及循环再吸附性能。结果表明:经硝酸改性后活性炭纤维的整体形貌保持不变,其表面含氧官能团及微孔数量增多。随着pH值的增大,改性吸附剂对铅离子的吸附量和吸附速率均大于未改性活性炭,用Langmuir吸附等温线模型和准二级动力学模型可以更好地描述此吸附过程,且改性活性炭纤维具有良好的循环再吸附性能。 相似文献
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活性炭纤维微孔结构分析方法 总被引:8,自引:0,他引:8
根据实测高精度氮气吸附等温线详细介绍了活性炭纤维微孔结构的分析方法如DR图、t图和αs图。由这三种分析方法获得的活性炭纤维的微孔容量相同,由t图和αs图获得的微孔结构参数也具有很好的一致性,DR图法有一定的理论基础,不需 要标准吸附等温线,能获得与微孔表面能相关的特征吸附能;t图和αs图法能得到总表面积,内表面积和外表面积,一般认为αs图法比t图法更适合于微孔结构的分析。 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.…… 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
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C. Qihong W. Zhan‐Wen J. Yi J. Yehua L. Fei F. Hanguang 《Materialwissenschaft und Werkstofftechnik》2014,45(7):582-590
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill. 相似文献
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《中国标准化(英文版)》2014,(4)
正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from 相似文献
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《中国标准化(英文版)》2014,(5)
正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively. 相似文献
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《中国标准化(英文版)》2014,(4)
正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to 相似文献