煤基成型活性炭活化实验研究及性能表征

以低变质粉煤与液化残渣为原料,水蒸气为活化剂,研究了活化时间与活化温度对成型活性炭吸附性能、抗压强度和活性炭收率的影响。采用N2吸附、SEM、碘吸附等手段对成型活性炭的孔径分布及吸附性能进行了分析表征。研究表明,经700℃炭化1.0h,800℃水蒸气活化1.5h制备的成型活性炭碘吸附值为820mg/g,活性炭收率为36.63%,抗压强度为0.08MPa,比表面积为509m2/g,其总孔容积达0.35cm3/g。随着活化时间的延长,成型活性炭的碘吸附值先增大后减小,炭化收率和抗压强度都逐渐降低;随着活化温度的升高,成型活性炭的碘吸附值先增大后减小,炭化收率和抗压强度都逐渐减小。     

PVA复合磷酸钙骨水泥的制备和性能研究

将含有不同质量分数聚乙烯醇(PVA)的PVA-KH2PO4-Na2HPO4体系缓冲溶液作为骨水泥的调和液,将其与磷酸钙骨水泥粉末混合后成型。将试样在接近生理条件(相对湿度100%,温度(37±1)℃)下养护24h,发现PVA掺入量为1%时的抗压强度达到31.71MPa,比未掺入的提高了将近70%。     

硅微粉及热处理温度对铝矾土基喷涂料性能影响

为了研究硅微粉在铝矾土基喷涂料中的应用,以铝矾土为主要原料,铝酸钙水泥为结合剂,分别研究不同硅微粉含量对铝矾土基喷涂料性能的影响。试样自然干燥24h脱模后,再经110℃烘干24h,分别于1000、1300、1500℃热处理3h。检测各温度热处理后试样的线变化率、体积密度、抗折强度、抗压强度以及试样的热膨胀系数。结果表明:铝矾土基喷涂料经过110℃烘干,1000、1300℃热处理后,抗折强度和抗压强度随着硅微粉含量的增加而增加。铝矾土基喷涂料的热膨胀系数随着硅微粉含量的增加而减小。制备铝矾土基喷涂料的最佳硅微粉质量分数为5%。     

蒸压养护对废玻璃粉复合砂浆力学性能的改善

为改善玻璃粉复合砂浆力学性能,参考蒸压加气砖的制备条件,用蒸压养护对比常温养护,以不同比例废玻璃粉取代水泥制备玻璃粉复合水泥砂浆;结合X射线衍射分析、扫描电镜等方法研究废玻璃粉复合砂浆力学性能的变化。结果表明:常温养护下,废玻璃粉复合砂浆强度随取代比例的提高而降低;蒸压养护下,玻璃粉复合砂浆强度随取代比例的提高而呈"凸"型变化,最优掺量为30%(质量分数),其60 d抗压强度超过基准水泥砂浆17. 6%,建议制备玻璃粉复合砂浆中玻璃粉的取代比为30%。     

微胶囊-玄武岩纤维/水泥复合材料的力学性能

以水泥、玄武岩纤维和脲醛/环氧树脂微胶囊为主要材料,制备水泥基复合材料标准试样,研究纤维掺量、纤维长度、微胶囊质量分数、水灰质量比和养护龄期对复合材料抗折强度和抗压强度的影响,利用正交实验确定微胶囊-玄武岩纤维/水泥自修复复合材料力学性能的最优配比。实验结果表明：抗折强度随着纤维掺量的增加而增加,抗压强度随着纤维掺量增加而减小;随着纤维长度的增加,抗折强度略有增加,抗压强度略有降低;抗折强度随着微胶囊质量分数的增加呈现出先增加后减小的趋势,而抗压强度则呈现下降趋势;抗折强度与抗压强度随养护龄期的增加而呈增加的趋势;材料经损伤后修复,抗折强度修复率为117%,恢复率为103%,抗压强度修复率为71%,恢复率为97%。     

甘蔗叶活性炭的制备工艺优化及表征

采用中心复合设计(CCD)方法研究活化剂浓度、活化温度及时间等对甘蔗叶活性炭得率及吸附性能的影响;运用Design Expert软件建立活性炭得率和碘吸附值的预测模型,优化甘蔗叶活性炭的制备工艺;并采用FTIR、SEM和XRD等方法对甘蔗叶及其活性炭的表面官能团、微观形貌和晶体结构进行分析。结果表明,甘蔗叶活性炭最优制备工艺:活化剂浓度为2.50%(质量分数)、活化温度为705℃、活化时间为65min,样品得率和碘吸附值分别为29.33%、987.69 mg/g,与模型预测值误差分别为7.88%、2.68%;甘蔗叶活性炭的孔径范围为735.1nm~7.16μm,微晶层距d(002)为0.3559nm,微晶尺度La、Lc分别为0.3054nm、0.1420nm,表面官能团主要有羧基、酚羟基、醇羟基、胺基等。     

聚氨酯后处理对发泡水泥保温板性能的影响

采用全水发泡填充和溶液浸泡两种后处理方式考察聚氨酯宏观结构对发泡水泥密度、孔形貌、吸水率、导热性能及强度的影响,并对其作用机制做了进一步探讨。研究发现,聚氨酯全水发泡填充使得发泡水泥容重下降,吸水率增加,抗压强度随着填充孔径减小而增大;经过聚氨酯溶液浸泡后的水泥发泡体系质量吸水率降低37.2%(质量分数),抗压强度提高364%,导热系数下降32.4%。     

基于吸附性能的生物质基多孔活性炭制备方案的响应面法优化

以废弃核桃壳作为原料,采用微波加热法制备生物质基多孔活性炭。基于响应面法和数值模拟方法研究活性炭前驱体进行物理活化过程中微波功率、活化时间以及磷酸质量分数对生物质基多孔活性炭吸附性能的影响,对生物质基多孔活性炭制备方案进行优化,并对最优条件下制备的生物质基多孔活性炭进行表征。结果表明,3个因素均对生物质基多孔活性炭的吸附性能有影响,其影响显著性为:微波功率磷酸质量分数活化时间。优化的制备条件为:微波加热法对活性炭前驱体进行物理活化过程中的微波功率为746W、活化时间为11.2min以及磷酸质量分数为85.9%。优化生物质基多孔活性炭的碘吸附值为1074.57mg/g,亚甲基蓝吸附值为294.4mL/g,获得率为52.1%。     

化学活化剂对铬铁渣水泥复合材料力学性能及水化的影响

以工业废弃物铬铁渣替代不同比例的水泥,并添加不同含量的KCl作为化学活化剂,成功制备了铬铁渣水泥复合材料。分析了铬铁渣掺量及KCl添加量对铬铁渣水泥复合材料抗压强度的影响,并利用傅里叶红外光谱、扫描电子显微镜、热重-差热分析等方法对不同水泥复合材料的样品进行了测试。结果表明,10%(质量分数)铬铁渣掺杂具有较好的抗压强度,且符合Cr~(6+)排放标准;0.6%(质量分数)的KCl加入到10%(质量分数)铬铁渣含量的水泥复合材料中,抗压强度最高,养护7,28和90 d后抗压强度分别为46.13,67.45和78.98 MPa;化学活化剂KCl的加入加速了钙矾石和C-S-H凝胶的形成,有利于提高水泥复合材料的致密性,同时化学活化剂中的氯离子可与水泥复合材料中粉煤灰提供的活性Al_2O_3反应生成水铝钙石,促进了熟料的水合作用,提高了水泥复合材料的早期强度和耐久性。     

压电材料对含铂活性炭氢气吸附性能的影响

用机械混合法制备含有不同质量分数铂的活性炭,研究了压电材料PMN-PT产生的电荷对含铂活性炭氢气吸附性能的影响。结果表明,在高压氢气条件下PMN-PT产生的电荷能增强铂和活性炭颗粒对氢气分子的吸附,并加速氢气分子的解离和氢原子的扩散,使含铂活性炭的储氢量明显提高。铂产生的氢溢流作用有效地提高了活性炭的氢气吸附量。在室温和8 MPa氢气压力条件下PMN-PT使活性炭(NAC)氢气吸附量产生的增长幅度为15%,使含有质量分数0.83%、1%和1.25%铂的活性炭氢气吸附量增长的幅度分别为36.5%、39.3%和43.9%。     

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