Mobil Zeolite Catalysts for Monomers

It has been about 20 years since Plank, Rosinski, and Hawthorne reported their spectacular results with metal-modified zeolite cracking catalysts for more efficient production of gasoline [1]. This discovery has saved an estimated 200 million barrels of crude oil each year in the United States alone [2]. In 1972, a patent by Argauer and Landolt described the preparation of a member of a generation of new synthetic zeolites, called ZSM- 5. It was unique because of its high silica/alumina ratio and greatly reduced coking rates for reactions with hydrocarbons by comparison with known low silica zeolites [3]. This material was an early member of a series of over 50 synthetic zeolitic substances prepared in Mobil laboratories.     

无底柱分段崩落法采矿进路受力过程分析

在使用无底柱分段崩落法的矿山,大都存在着地压现象。其主要表现是采矿进路和联络道的变形破坏。对采矿进路在开挖和回采过程中各阶段受力情况的分析表明,进路的变形、破坏主要是受到岩体初始静应力、爆破动应力和矿柱支撑应力的综合作用的结果。     

Ozone-Based Advanced Oxidation Processes for the Decomposition of N-Methyl-2-Pyrolidone in Aqueous Medium

The present study investigates the decomposition of N-Methyl-2-Pyrolidone (NMP) using conventional ozonation (O₃), ozonation in the presence of UV light (UV/O₃), hydrogen peroxide (O₃/H₂O₂), and UV/H₂O₂ processes under various experimental conditions. The influence of solution pH, ozone gas flow dosage, and H₂O₂ dosage on the degradation of NMP was studied. All ozone-based advanced oxidation processes (AOPs) were efficient in alkaline medium, whereas the UV/H₂O₂ process was efficient in acidic medium. Increasing ozone gas flow dosage would accelerate the degradation of NMP up to certain level beyond which no positive effect was observed in ozonation as well as UV light enhanced ozonation processes. Hydrogen peroxide dosage strongly influenced the degradation of NMP and a hydrogen peroxide dosage of 0.75 g/L and 0.5 g/L was found to be the optimum dosage in UV/H₂O₂ and O₃/H₂O₂ processes, respectively. The UV/O₃ process was most efficient in TOC removal. Overall it can be concluded that ozonation and ozone-based AOPs are promising processes for an efficient removal of NMP in wastewater.     

橡胶模型制品胶坯精密预成型机

介绍了橡胶工业橡制品生产中胶坯制备的三种方法，其中详细介绍了精密预成型机制备胶坯。以上海德仁橡塑机械有限公司物精密预成型机为例，从结构，性能及工艺参数等方面进行了分析，说明精密预成型机是批量生产橡胶模型制品的一种得力辅助设备。     

Photoinitiated crosslinking of ethylene‐vinyl acetate copolymers and characterization of related properties

Photoinitiated crosslinking of EVA in the presence of benzophenone (BP) as photoinitiator and triallyl isocyanurate (TAIC) as crosslinker and characterization of the related properties have been studied by gel determination, heat extension, DSC, DMTA, TGA, and mechanical measurements. The photoinitiated crosslinking efficiency of the EVA‐BP‐TAIC system and various factors affecting the crosslinking process, such as photoinitiator and crosslinker and their concentrations, irradiation temperature, and irradiation atmosphere were studied in detail and optimized by comparison of gel contents. The results show that the EVA samples with a thickness of 1 mm are readily crosslinked to a gel content of above 80% with 5 s UV‐irradiation under optimum conditions. The data from the heat extension and DSC show that the crosslinking density of photocrosslinked EVA increase and their crystallinities decrease with increasing the UV‐irradiation time. At the same time, photocrosslinking of EVA leads to a lowering of the melt temperature and a decrease of heat of fusion. The DMTA results show that photocrosslinking increases the amorphous phase and storage modulus of the crosslinked EVA, but does not change the glass transition temperature. The data from TGA and mechanical tests give evidence that the thermal stability and mechanical properties of photocrosslinked EVA samples are much better than those of the uncrosslinked EVA. POLYM. ENG. SCI., 47:1761–1767, 2007. © 2007 Society of Plastics Engineers     

Mathematical model of deoxidization with post stirring in a combined blowing converter

Dissolved oxygen in the steel at the terminal of the converter smelting process is the main cause for the formation of oxide inclusions, and the high terminal oxygen content worsens the steel cleanness. However, post stirring in a combined blowing converter can promote the carbon-oxygen reaction in the liquid steel and reduce the dissolved oxygen content at the terminal of the converter smelting process. Thus, the mathematical model of deoxidization in the post stirring process was obtained, and the rationa...     

高校和谐平安校园建设研究

围绕创建和谐平安校园、实现学校新一轮发展的战略目标,必须要建立健全的思想政治工作机制,完善沟通机制,健全保障机制,构建公平公正的法治环境。     

课外科技活动与大学生创新能力的培养

高等学校是培养创新人才的基地和摇篮,肩负着重要的历史使命。必须全方位更新观念,把培养大学生的创新能力作为教育改革的核心。而开展大学生课外科技活动,是激发学生创新意识、提高学生综合素质的重要手段,有利于营造浓厚的科技氛围,促使学生理论联系实际,培养实践能力,激发创新能力。     

循环经济在赣州矿产资源开发与管理中的研究

如何利用赣州矿产资源优势发展本地经济,节约资源开采,充分利用现有资源,实现资源的循环利用,保持生态环境的良好发展具有重要意义。本文分析介绍了循环经济、赣州矿产资源及开发利用现状,并提出了实现矿业循环经济的具体措施。