New Pretreatment for Elastomers to Enhance Adhesion

The effects of various chemical pretreatments on the surface chemistry and adhesion performance of an additive-free styrene-butadiene block copolymer and an additive-free ethylene-propylene elastomer have been studied. Most of the powerful oxidising agents that are effective with hydrocarbon plastics were ineffective in enhancing the adhesion to elastomers despite causing major changes to their surface chemistries. The poor adhesion was attributed to the existence of weak boundary layers. Chlorinated agents were also examined and a new pretreatment for elastomers containing carbon-carbon double bonds has been identified. It was found that a mildly acidified dilute aqueous suspension of Chloramine-T was very effective at enhancing the adhesion performance of styrene butadiene copolymers.     

ANALYSIS OF COAL DISSOLUTION REACTION ENGINEERING

A phenomenological approach was developed for conversion of coal to pyridine soluble materials with the object of shedding additional light on the reactions taking place during short contact times. The approach was based on a theoretical analysis of many parallel reactions in a complex reacting mixture. The analysis used the concept of lumped species and weighted activation energies to improve on coal liquefaction models. i.e. to remove insensitivity problems for parameters in coal liquefaction models and to answer questions about behaviour of liquefaction reactions in different vessels.     

The effect of scale and interfacial tension on liquid–liquid dispersion in in-line Silverson rotor–stator mixers

The effect of scale, processing conditions, interfacial tension and viscosity of the dispersed phase on power draw and drop size distributions in three in-line Silverson rotor–stator mixers was investigated with the aim to determine the most appropriate scaling up parameter. The largest mixer was a factory scale device, whilst the smallest was a laboratory scale mixer. All the mixers were geometrically similar and were fitted with double rotors and standard double emulsor stators. 1 wt.% silicone oils with viscosities of 9.4 mPa s and 339 mPa s in aqueous solutions of surfactant or ethanol were emulsified in single and multiple pass modes. The effect of rotor speed, flow rate, dispersed phase viscosity, interfacial tension and scale on drop size distributions was investigated.     

Dispersion of water into oil in a rotor–stator mixer. Part 1: Drop breakup in dilute systems

Most previous studies of liquid–liquid dispersion in complex geometry are limited to turbulent flow at low continuous phase viscosity. In this study, a viscous continuous phase was employed over a range of flow conditions including both the laminar and turbulent regimes. Equilibrium drop size was measured for water dispersed into viscous food grade mineral oils in a batch Silverson L4R rotor–stator mixer. The influence of fluid viscosities and interfacial tension (by adding an oil-soluble surfactant) were examined. In order to isolate the effect of drop breakage from coalescence, Part 1 is limited to dilute conditions (water phase fraction, ? = 0.001). In the laminar regime, drop breakup was more likely due to a simple shear breakage mechanism than one for extension. Following Grace (1982), a semi-empirical drop size correlation was developed. For turbulent flow, the validity of the sub-Kolmogorov inertial stress model for correlating equilibrium mean drop size was verified. Surfactants were found to mostly decrease drop size by lowering interfacial tension. Except for laminar systems near the critical micelle concentration, where Marangoni stresses appear to play some role, the effect of surfactants on the drop size could be correlated using the equilibrium or static interfacial tension. The influence of water phase fraction and coalescence is considered in Part 2 ( Rueger and Calabrese, 2013) of this paper.     

焦炉新型煤气掺混器的开发与应用

针对以往煤气混合器的优缺点,设计开发了新型煤气混合器。新型煤气混合器具有掺混均匀、不易堵塞、操作方便安全等优点,对降低能源消耗和生产成本有积极的作用。该掺混装置应用于多个焦炉项目中,运行状态良好。     

过磷酸钙干湿法结合的生产工艺

针对用浏阳磷矿生产过磷酸钙产品物性差的问题,采用干、湿法结合的生产工艺,对混合器进行改造,阐述改造中的技术要点。改造后成品肥外观物性大为改善,技术和经济优势明显,并指出生产中尚存在的问题,     

SIEMENS 6RA70全数字直流调速装置在密炼机中的应用

GK400N密炼机的两台1250kW直流电机是通过两台SIEMENS 6RA70直流调速器进行控制的。具体说明主、从电机调速器的速度、电流控制方式设定,及整流器功率部件、整流器控制字、密炼机电机参数及一些基本工艺参数的设定方法及数值。该控制系统调试好后运行稳定。     

强力数控龙门钻床的设计

设计的龙门钻床采用双柱定梁龙门架以及圆盘回转工作台结构,能够实现对圆盘类零件孔的强力钻削加工。运用ANSYS软件分析机床横梁的静力特性,结果表明:所设计的横梁能满足强度要求。     

一种改性铵油炸药连续化生产中的均匀混合设备

文章介绍了改性铵油炸药连续化生产的关键性混合设备之一卧式多辊连续混合机,对该设备的结构特征、工作原理、混合过程及安全措施进行分析,认为该设备能充分适应改性铵油炸药连续化生产工艺要求,对改性铵油炸药连续化自动化生产和发展具有重大意义。     

六棱同步转子密炼机混炼性能的研究

本实验采用六棱同步转子密炼机,配方采用全钢子午胎胎面胶,通过对六棱同步转子密炼机在不同填充系数、冷却水温度、上顶栓压力、转子转速的条件下的实验,具体分析了混炼胶各种物理机械性能的差异以及产生的原因,并找出了最佳的工艺条件：填充系数0．6,冷却水温度40℃,上顶栓压力0．5MPa,转子转速160r／min。