兰炭基中孔活性炭的制备及性能表征

以兰炭粉为原料,水蒸汽为活化剂,采用物理活化法制备中孔活性炭。分别讨论了活化温度、活化时间、水蒸汽质量流量对活性炭碘吸附值的影响,并采用正交实验对工艺条件进行了优化。利用全自动物理吸附仪对活性炭的比表面积和孔结构进行表征。结果表明:随着活化温度的升高、活化时间的延长和水蒸汽流量的增大,活性炭的碘吸附值均呈现先升高后下降的变化规律。正交实验结果表明,水蒸汽活化兰炭粉的适宜条件为:活化温度900℃,活化时间60min,水蒸汽流量1.25g/min。此条件下制得的活性炭具有多级孔的特征,而且以中孔为主,其碘吸附值为924.45mg/g,比表面积为818.52m2/g。     

响应曲面法优化小桐子壳基活性炭制备条件的实验研究

采用水蒸气物理法制备小桐子壳基活性炭,通过响应曲面法中模型的优化设计和分析,研究了制备过程中的3个影响因子(活化温度、活化时间以及水蒸气流量)对活性炭碘吸附能力和得率的影响,并通过方差分析(ANOVA)研究了各个实验因子或交互作用对活性炭性能的影响。经过优化所获得的实验条件为:活化温度900℃,活化时间22min,水蒸气流量5.5g/min,获得的活性炭碘值为950mg/g,得率为13%,比表面积为785m2/g。     

水蒸气活化再生扑热息痛用废活性炭的研究

以扑热息痛生产过程中产生的废活性炭为研究对象,采用管式电阻炉的加热方式对其进行再生条件的研究。实验重点考察了在氮气作为保护气体的条件下再生温度、再生时间、水蒸气流量3个因素对再生活性炭亚甲基蓝吸附性能和得率的影响。得到了废活性炭再生的最佳实验条件:再生温度750℃,再生时间20min,水蒸气的流量2.0mL/min。在最佳实验条件下得到的再生活性炭的亚甲基蓝吸附值为184.5mg/g,得率70.56%,在此条件下测得再生活性炭的比表面积为996.8m2/g,总孔体积为0.995mL/g。通过对废活性炭和再生活性炭扫描电镜的分析发现再生后的活性炭孔隙数量增多并且其表面杂质明显减少。     

山竹壳基生物质活性炭的制备及其吸附性能研究

采用山竹壳为原料制得山竹壳基生物质活性炭。确定了较佳的制备条件:在尿素酸溶液∶碳=1∶1(质量比)的浸渍比下,浸渍时间15h,活化温度750℃,活化时间60min,制得的山竹壳基生物质活性炭比表面积为545.68m2/g。在亚甲基蓝溶液pH=4.5、初始浓度为25mg/L,山竹壳基生物质活性炭用量为0.06g条件下,山竹壳基生物质活性炭对亚甲基蓝的吸附量达到68.75mg/g。     

海枣核CO2活化和磷酸活化制备活性炭及其结构、吸附性能（英文）

由于具有很大的吸附容量,多孔炭材料是优良的吸附剂。笔者试图比较海枣核分别经CO2活化和磷酸活化所制活性炭的结构和吸附性能。活化过程和工艺条件对炭的物理化学性质影响较大,根据文献报道的结果选取了优化的工艺参数。基于氮气吸附等温线、SEM、FT-IR等分析结果,评估了活性炭的结构特征,吸附性能则由亚甲蓝吸附值表示。CO2活化得到了微孔活性炭,产率为44%、BET比表面积是666 m2·g-1;磷酸活化得到了产率为14.8%的中孔活性炭,BET比表面积为725 m2·g-1。CO2活化活性炭的平均孔径是1.51 nm,磷酸活化活性炭的则为2.91 nm。活性炭的亚甲蓝吸附等温线分别用Langmuir等温线和Freundlich等温线进行了验证,在优化工艺条件下制备的CO2活化炭和磷酸活化炭的亚甲蓝w单分子吸附容量分别为110 mg·g-1和345 mg·g-1。然而,磷酸活化产生的亚甲蓝吸附值最高达455 mg·g-1。     

H3PO4活化紫茎泽兰制备活性炭及其性能研究

以紫茎泽兰为原料,采用H_3PO_4活化的方式在管式电阻炉中加热制备紫茎泽兰基活性炭。主要考察以N2作保护气体时活化温度、保温时间以及H_3PO_4浓度(质量分数)对活性炭吸附性能及得率的影响。获得优化实验条件:活化温度400℃、保温时间60 min、H_3PO_4浓度50%,并测得相应的亚甲基蓝吸附值为210 mg/g、得率为59.70%,其中亚甲基蓝吸附值为国家标准GB/T 13803.2-1999活性炭一级品的1.6倍。优化实验条件下活性炭的BET比表面积、总孔体积、平均孔径分别为1346m2/g、0.83cm3/g、2.45nm,同时用傅里叶变换红外光谱(FT-IR)和扫描电镜(SEM)对活性炭进行分析表征。实验结果表明紫茎泽兰是一种制备活性炭的良好前驱体材料。     

磷酸活化甘蔗叶制备活性炭的工艺研究

采用正交试验方法系统研究了活化剂、添加剂、活化温度、活化时间等因素对磷酸活化甘蔗叶制备活性炭的得率、亚甲基蓝吸附值的影响,并利用SEM对样品进行了表征。结果表明,磷酸活化甘蔗叶制备活性炭的最佳工艺为:将甘蔗叶浸泡于6%添加剂1及1%添加剂2、体积浓度为35%的磷酸溶液中,浸泡12h后,在673K条件下活化40min,所制得的活性炭的微观孔结构排列整齐,活性炭的得率和亚甲基蓝吸附值分别为47.05%、202.50mg/g,其中亚甲基蓝吸附值为国家标准GB/T 13803.2-1999活性炭一级品的1.5倍。     

成型工艺对活性炭孔结构及其CO_2吸附性能的影响

用比表面积1183m2/g的活性炭和酚醛树脂分别作为吸附剂和粘结剂,考察了成型工艺对活性炭孔结构及其CO2吸附性能的影响。结果表明,活性炭成型后,比表面积有所下降,但对成型活性炭进行CO2二次物理活化可使其比表面积提高60.7%;粘结剂含量为30wt%、成型压力10MPa条件下所制的成型活性炭在800℃用CO2二次活化2h后,其比表面积、压缩强度和对CO2的平衡吸附量分别为1323m2/g、12.7MPa和0.67mmol/g。     

K_2CO_3活化法制备芋叶柄基活性炭的研究

以废弃的芋叶柄为原料,K2CO3为活化剂,制备芋叶柄基活性炭,考察炭化和活化工艺条件对活性炭吸附性能的影响,采用等温氮吸脱附测试、扫描电子显微镜(SEM)对样品材料进行了测试。结果表明:若以碘吸附值作为评价指标,最佳工艺条件为K2CO3浓度200g/L、活化温度850℃、活化时间35min,碘值为1930.4mg/g,BET比表面积为633.215m2/g,孔容为0.194cm3/g,孔径为18.45nm。以亚甲基蓝吸附值作为评价指标,最佳工艺条件为K2CO3浓度175g/L、活化温度875℃、活化时间35min,亚甲基蓝吸附值为298.8mg/g,BET比表面积为604.708m2/g,孔容为0.076cm3/g,孔径为18.533nm。     

CO2活化-碱液沸煮制备高介孔率的稻壳活性炭

以CO2活化-碱液沸煮新工艺制备高介孔率的稻壳活性炭,即先以CO2活化,后用NaOH溶液沸煮;采用正交试验研究CO2流量、CO2活化时间、NaOH浓度、NaOH沸煮时间、液固比对活性炭碘值的影响,并优化制备条件;采用N2吸脱附法表征活性炭;探讨孔隙发展机理。结果表明:采用CO2活化-碱液沸煮工艺,可以在无机碱不必经历高温过程的情况下制得介孔率高达79%的稻壳活性炭,其比表面积、孔容积、产率分别达到899m2/g、0.783 cm3/g、26.2%。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

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.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

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.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

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.……     

Optimum-Simulation von Ernteprozessen

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.     

A study of centrifugal cast high boron high speed steel

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.     

Brainstorming for ISO Strategy 2016-2020

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     

CNAS Passes APLAC's PTP Review

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.     

新闻(英文)

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