用于催化剂成型的前挤式双螺杆挤条机

介绍了催化剂成型设备－前挤式双螺杆挤条机的工作原理及在催化剂成型生产中的应用试验。     

用于催化剂成型的前挤式双螺杆挤条机

介绍了催化剂成型设备———前挤式双螺杆挤条机的工作原理及在催化剂成型生产中的应用试验。     

MC—15T催化剂挤条成型的研究

在MC-15T催化剂加工过程中,添加15～17％粘合剂可增加其抗磨耗能力,挤条成型的催化剂具有良好的催化活性。     

一种新型液压挤条机的开发和应用

分析了原有预成型和液压挤条两段式生产工艺存在的缺点,自主研发了一种新型的一体式的液压挤条机,介绍了该挤条机的工作原理和结构特点,并成功地将其应用于裂解汽油加氢催化剂载体的生产。试验结果表明:使用新型液压挤条机生成后,单台设备的产能由0.25 m3/天提高到1.5 m3/天,单位人数由7人/班减少到4人/班,单位能耗由15 kW·h下降到7.5 kW·h。     

分子筛对挤条成型强度影响因素的考察

采用氧化铝、硝酸成型体系,以挤条成型法研究分子筛质量分数、硅铝比、颗粒大小、孔容、比表面积和杂质含量等因素对载体机械强度的影响。结果表明,分子筛质量分数低于60%时,随着分子筛质量分数下降,载体强度升高,高于60%时强度变化不明显;同一种分子筛的硅铝比越高,成型强度出现降低趋势;随着分子筛颗粒尺寸和孔容变小,成型强度逐渐上升;比表面积对强度影响较小;分子筛中的硅杂质含量对成型强度影响较大,硅含量高则强度降低。指出结合相应的反应性能需求,制备物化性质适宜的分子筛以保证载体具有适宜的强度。     

催化剂单螺杆挤条机的设计

为适应催化剂的成型生产,设计了专用的单螺杆挤条机,并阐述该机的工作原理、总体结构、主要零部件的设计及注意事项。     

挤条成型TS-1分子筛催化剂制备及性能表征

制备了TS-1分子筛挤条成型催化剂。并采用傅里叶红外光谱(FT-IR),X射线衍射(XRD),N_2吸附,激光粒度分析等手段对其进行了表征,考察了TS-1原粉含量,烧成温度,保温时间,焙烧气氛等工艺条件对成型催化剂的机械强度和催化性能的影响。结果表明,同TS-1原粉相比,TS-1分子筛挤条成型催化剂的骨架保留了MFI的拓扑结构,但其比表面积及孔容均有所降低;挤条成型TS-1分子筛适宜的制备条件为烧成温度800℃,保温时间4 h,焙烧气氛O_2,TS-1原粉含量80%,此条件下制得的成型催化剂压碎强度为22.3 N/mm,催化环己酮氨肟化反应环己酮肟收率可达99.1%。     

浸渍方式对挤条成型Mo/ZSM-5催化剂甲烷无氧芳构化反应性能的影响

以SiO_2为粘结剂,通过不同浸渍方式制备了挤条成型的Mo/ZSM-5催化剂,考察其催化甲烷无氧芳构化的反应性能。采用扫描电镜(SEM)、紫外拉曼光谱(UV-Raman)及程序升温还原法(H_2-TPR)等对催化剂进行了表征。结果表明,碱性浸渍液有利于成型催化剂中Mo物种的分散,促进了Mo物种的还原,芳烃增加约13%,积碳量下降约8%。     

浸渍方式对挤条成型Mo/ZSM-5催化剂甲烷无氧芳构化反应性能的影响

以SiO_2为粘结剂,通过不同浸渍方式制备了挤条成型的Mo/ZSM-5催化剂,考察其催化甲烷无氧芳构化的反应性能。采用扫描电镜(SEM)、紫外拉曼光谱(UV-Raman)及程序升温还原法(H_2-TPR)等对催化剂进行了表征。结果表明,碱性浸渍液有利于成型催化剂中Mo物种的分散,促进了Mo物种的还原,芳烃增加约13%,积碳量下降约8%。     

聚酰胺荷电镶嵌膜的制备及表征(英文)

A novel composite charged mosaic membrane(CCMM) was prepared via interfacial polymerization(IP) of polyamine[poly(epichlorohydrin amine) ]and trimesoyl chloride(TMC) on the polyethersulfone(PES) support. Fourier transform infrared spectroscopy(FT-IR) ,environmental scanning electron microscopy(ESEM) ,atomic force microscopy(AFM) and water contact angle analysis were applied to characterize the resulted CCMM.The FT-IR spectrum indicates that TMC reacts sufficiently with polyamine.ESEM and AFM pictures show that the IP process produces a dense selective layer on the support membrane.The water contact angle of the CCMM is smaller than that of the substrate membrane because of the cross-linked hydrophilic polyamine network.Several factors affecting the IP reaction and the performance of the CCMM,such as monomer concentration,reaction time,pH value of aqueous phase solution and post-treatment,were studied.The pure water flux of the optimized CCMM is 14.73 L·m -2 ·h -1 ·MPa -1 at the operating pressure of 0.4 MPa.The values of separation factorαfor NaCl/PEG1000/water and MgCl2/PEG1000/water are 11.89 and 9.96,respectively.These results demonstrate that CCMM is promising for the separation of low-molecular-weight organics from their salt aqueous solutions.     

基于Pro/E的塑料模具设计研究

阐述了Pro／E软件在开关体塑料模设计中的应用。通过实例分析，说明Pro／E软件在塑料模设计中的应用可以大大提高设计效率和设计质量，是塑料模设计发展的一种趋势。     

塑料异型材挤出口模设计的数值模拟概述

从挤出口模设计原则出发,综述了数值模拟技术在塑料异型材口模流道的曲面构型,入口角和压缩比、降低或消除挤出胀大和挤出口模成型段的设计、熔体流动平衡和压力降的研究进展,以及口模设计的发展趋势.     

Effect of fiber length on processing and properties of extruded wood‐fiber/HDPE composites

Fiber length and distribution play important roles in the processing and mechanical performance of fiber‐based products such as paper and fiberboard. In the case of wood–plastic composites (WPC), the production of WPC with long fibers has been neglected, because they are difficult to handle with current production equipment. This study provides a better understanding of the effect of fiber length on WPC processing and properties. The objectives of this study were therefore to determine the role of fiber length in the formation process and property development of WPC. Three chemithermomechanical pulps (CTMP) with different lengths, distributions, and length‐to‐diameter ratios (L/D) were obtained by mechanical refining. Length, shape, and distribution were characterized using a fiber quality analyzer (FQA). The rheometer torque properties of high‐density polyethylene (HDPE) filled with the pulps at different loads were studied. Variations in fiber load and length distribution resulted in significant variations in melting properties and torque characteristics. Composites from the three length distributions were successfully processed using extrusion. Physical and mechanical properties of the obtained composites varied with both length distribution and additive type. Mechanical properties increased with increasing fiber length, whereas performance in water immersion tests decreased. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Study on binder of extruded mordenite catalyst for dimethyl ether carbonylation

The carbonylation of dimethyl ether (DME) to produce methyl acetate (MA) and the hydrogenation of MA to ethanol is a novel, green and economical ethanol synthesis route. The formation of the catalyst is of great significance to the industrialization of this process. In this paper, pseudo-boehmite and silica sol are used as binders, and mordenite molecular sieve (MOR) is extruded to prepare a series of molded MOR catalysts with different binder types and contents. By using strength evaluation and Weibull distribution analysis, we investigated the mechanical stability and reliability of the extruded MOR. Afterwards, XRD, N₂-physisorption, NH₃-TPD and IR spectra of pyridine adsorption were employed to explore the influence of binder on textural properties, acidity and catalytic performance. The results showed that the crystal structure of MOR was maintained after addition of binder. When the pseudo-boehmite was used as a binder, the catalyst showed the best mechanical property and catalytic activity. By establishing the quantitative relationships among the yield, TOF and structure parameter, it is found that the space time yield of MA was linearly related to the specific surface area of micropores. Meanwhile, the almost constant TOF indicated that the binders did not affect the catalytic capacity of each activesites in MOR for carbonylation of dimethyl ether.     

开孔微孔塑料的研究进展

综述了开孔微孔塑料的制备方法,介绍了基于间歇成型法制备开孔微孔塑料的开孔理论,分析了间歇成型法的工艺条件对开孔结构的影响。提出今后的研究方向是建立连续挤出过程中的开孔理论,尽早实现实验室成果向商业应用的转化。     

塑性挤压成型90氧化铝陶瓷工艺研究

研究了塑性挤压成型生产90氧化铝陶瓷新工艺，进行了吨级规模氧化铝瓷球工业生产试验。结果表明，塑性挤压成型较之等静压成型生产90氧化铝陶瓷，具有工艺设备简单，投资小，成本低，产品适用面宽的优点。用本工艺试制的1号氧化铝瓷球比重大于3.54g/cm^3，干磨磨耗0.100-0.12g/kg.h，湿磨磨耗0.230-0.356g/kg.h，可与用相同原料配方，等静压成型生产的氧化铝瓷球的磨耗值（干磨0.111-0.141g/kg.h，湿磨0.235-0.352g/kg.h)相媲美。本工艺可推广应用于外形各异，断面相同的棒，管，柱，板状90氧化铝陶瓷异型件的规模生产。     

Antiviral activity and mechanism of action of novel thiourea containing chiral phosphonate on tobacco mosaic virus

Using half-leaf method O,O'-diisopropyl (3-(L-1-(benzylamino)-1-oxo-3- phenylpropan-2-yl)thioureido)(phenyl)methyl phosphonate (2009104) was studied for its activity on tobacco mosaic virus (TMV). It showed good curative activity in vivo and the curative activity at 500 μg/mL was found to be 53.3%. In vivo treatment with the control agent Ningnanmycin at 500 μg/mL resulted in 51.2% inhibition and curative inhibition rates respectively. Dot-ELISA test was employed to verify the efficacy of activity of compound 200910 for anti-TMV activity. The mechanism of action of compound 2009104 to resist TMV was also studied. The results showed that the resistance enzymes PAL, POD, SOD activity and chlorophyll content after TMV inoculation K(326) (Nicotiana tabacum K(326)) of tobacco plants followed by treatment with compound 2009104 were significantly enhanced. The study of the effect of compound 2009104 on TMV capsid protein (CP) showed that it inhibited the polymerization process of TMV-CP in vitro.     

一种切粒装置的改进设计

文中切粒装置与挤出机配套使用,用于高分子聚合物,尤其是弹性体的挤出成型、切粒。本文针对原有切粒装置存在的诸多问题,对其模套、切刀轴、调距方式进行了改进,并重新确定相关参数,从而使改进后的装置更加适合生产工艺的要求,并达到了满意的效果。     

Study on the Accuracy of Injection Molded Plastic Gear with the Assistance of Supercritical Fluid and a Pressurized Mold

Plastic gears are lighter and less noisy compared to steel gears, and they can be easily shaped into diverse forms by the injection molding process. For this reason, plastic gears are widely used in industry. An extensive amount of research has been conducted on gear materials and methods of shaping plastic gears for durability and for broader applications. In this article, the focus is on producing a plastic gear shaping method incorporating the injection molding process.

The most important factor influencing the durability of a plastic gear is its accuracy. Unlike steel gears, the dimensions of plastic gears are subject to considerable change during formation, and this is due to certain conditions during the injection molding process and to the mold structure. The main causes of size variability here are the high viscosity of plastic and the shrinkage ratio of the resin. In our study, a supercritical fluid was used to reduce the viscosity of the plastic, and a pressurized mold was used to control the shrinkage ratio of the resin. Thus, production of an improved, more highly accurate plastic gear was achieved.