一种新型粉体分散装置的实验研究

为了获得高质量的粉体气溶胶,开发了一种依据浮动压差原理设计的新型粉体分散装置,同时利用该装置进行不同粒径滑石粉的分散实验,分析气溶胶生成质量,考察气体压力、气流量及粉体剩余量等因素时粉体输送量的影响。该分散装置采用锥体流化板结构使物料与空气充分混合,在空气中形成有效的粉体气溶胶,并通过流量控制装置控制气体压力和流量,从而控制粉体的输送速度和输送量。结果表明,该装置能够生成粒径在2μm左右的固体气溶胶,可以通过控制高压空气流量控制粉体输送量。     

实时在线测量烟幕气溶胶质量浓度的新方法

为了探索一种实时在线测量烟幕气溶胶质量浓度的新方法,利用电子低压冲击仪对不同烟剂装填量、压力及施放时间条件下形成的烟幕气溶胶质量浓度进行测试分析。结果表明:利用电子低压冲击仪可以实时在线测量烟幕气溶胶质量浓度,当施放压力、烟剂装填量及施放时间改变时,对气溶胶粒子数浓度和质量浓度分布均有不同影响。烟剂装填量增大,粒子数浓度和质量浓度均相应增大;施放压力增大时,粒子数浓度略有增大。     

超微粉体分散技术在防治呼吸系统疾病中的应用

为了探讨超微粉体分散技术在防治呼吸系统疾病中应用的可行性,提高粉体药物的利用率,降低粉体药物吸入治疗的不良反应,采用低压旋转气体的分散技术使药物粉体与空气充分混合,通过三次旋转加速喷出,在空气中生成了高浓度药物单质气溶胶。结果表明,该技术能够分散多种中西药物粉体,能够控制粉体药物气溶胶的浓度,解决了超微粉体的二次团聚问题,试验动物在20μg/m3的药物气溶胶浓度下,停留1min后开始有反应。     

HEAE气溶胶出口温度控制的实验研究

高效气溶胶灭火剂(HEAE)是由固体推进剂技术发展而成,属于烟火类药剂.当HEAE灭火剂生成气溶胶,出口气溶胶温度很高,会对被保护空间形成二次危害,影响灭火效果,因此灭火装置喷放时需作降温处理.针对灭火装置的特点,采用外冷却方法,利用固化的化学冷却剂,对高温HEAE燃烧产物实施冷却处理.重点考察了冷却块中冷却剂的含量、冷却块的孔径以及冷却块与HEAE灭火剂重量比对冷却降温效果的影响.结果表明,通过合理调节冷却块中冷却剂的含量、冷却块的孔径以及冷却块与HEAE灭火剂质量比,能有效地降低灭火装置喷口处的气溶胶灭火介质的温度.     

天然气水合物合成实验

为提高天然气水合物的生产效率及储气密度,在专门设计的水合物合成实验装置上,进行了纯甲烷水合物的合成实验。实验结果表明:对于纯净甲烷水合物,压力越高,合成速率越大;但当压力大于5 MPa时,压力的提高对生成速率的影响不大。水合物合成前抽真空时间越长,生成的水合物吸收的气体量越大,表明抽真空可以排出水中溶解的气体,提高水合物的储气密度。     

CFD仿真的湿式除尘器流场均匀性的优化设计

湿式电除尘器(WESP)对粉尘的适应能力强,能达到很高的除尘效率,并且能有效去除烟气中的亚微米级颗粒、SO3气溶胶和石膏微液滴,对控制PM2.5、蓝烟和石膏雨效果良好.我们利用计算流体力学(computational fluid dynamics,CFD)软件Fluent,对某电厂湿式除尘器机组内部流场进行了仿真研究.根据湿式除尘器管道内的气流分布情况,设计导流板和气流分布板,保证了在湿式电除尘器第一电场入口处的气流均匀性,以保证湿式电除尘器达到最高效的除尘效果.     

微型变压吸附制氧装置氧气回收率研究

对影响微型变压吸附装置氧气回收率的出口压力、系统压力、吸附剂、制氧流程、产品气流量以及关键部件等进行了实验研究,提出了提高氧气回收率的几点措施。     

基于荧光法生物气溶胶监测仪计数效率评价及方法研究

生物气溶胶监测仪是一类快速、实时监测空气中生物气溶胶的新兴仪器。为系统评价生物气溶胶监测仪的计数效率,开展了荧光法生物气溶胶监测仪总粒子和荧光粒子2个通道的计数效率评价。首先设计搭建了1套生物气溶胶监测仪计数效率评价装置,然后通过表面原子转移自由基聚合反应(SI-ATRP)制备了单分散、荧光性质稳定的荧光聚苯乙烯微球。采用制备的荧光微球雾化法发尘,模拟生物气溶胶环境,开展计数效率的评价,总粒子数和荧光粒子数计数效率分别为98.9%和98.1%,评价结果表明搭建的装置能满足荧光法生物气溶胶监测仪计数效率的评价需求,对生物气溶胶检测具有意义。     

基于振动床的细长型金属管粉体材料装填中的稳定给料模型

为了解决在将粉体材料装入细长型金属管的装填过程中一次给料太多会堵塞下料管的问题,以实现装填过程中给料量的稳定性和可控性,提出基于振动床的稳定给料方法;通过机理分析的方法,分析振动床中团聚体的尺寸、运动速度与振幅、振动频率的关系,建立基于振动床的给料量模型。结果表明,该模型可以对相关参数的设置进行指导和优化,基于求解的相关参数的实验研究验证了模型的有效性。     

PVC树脂低温超细气流粉碎研究

对PVC树脂进行低温冷脆处理,可以有效地实现PVC树脂的超细粉碎。利用PVC树脂低温超细气流粉碎系统通过液氮致冷降低粉碎温度。使PVC超细粉碎效率得到提高。并在每千克PVC粉体液氮耗量为131mL～167mL的范围内。每小时获得8．23kg～11．65kg、平均粒径为6．45μm～9．02μm的超细PVC粉体。     

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