Development of polyurethane elastomer composite materials by addition of milled fiberglass with coupling agent

Polyurethane elastomer composites were developed using milled fiberglass and their mechanical properties were studied. In particular, the organically chemical treatment of the milled fiberglass was investigated in detail. It was demonstrated that both strength and toughness of the resulting elastomer composites were improved considerably with the addition content of fiberglass. Furthermore, it was indicated that the optimal properties can be achieved by the proper addition of milled fiberglass that was chemically treated using coupling agent.     

Strength and chemical resistance of mortars containing brick manufacturing clays subjected to different treatments

This paper presents the results of an investigation of the properties of mortar in which a calcined clay was employed as a pozzolan. Mortars were prepared using either heat treated clay or ground waste clay bricks (from the same clay subjected to 1000 °C calcining) as a pozzolanic partial replacement for cement at replacement levels of 10%, 20% and 30%. The compressive strengths of the mortars were monitored up to 90 days and the resistance to sodium sulphate solution and synthetic seawater was monitored up to 300 days. The specimens were also monitored for weight changes. Partially replacing cement by ground brick or heat-treated brick clay gives early strengths that are lower than that of the control. At 90 days, however, the strengths are the same as or are greater than that of the control. Heat-treated clay is effective in reducing expansion during exposure of the mortar to sulphate solution and synthetic seawater. The rapidly cooled clay gives better performance, in terms of strength development and resistance to harmful solutions, than the slow cooled clay.     

Thermal stability of metal-doped diamond-like carbon fabricated by dual plasma deposition

Metal incorporation into amorphous diamond-like carbon films can provide superior properties as metal nano-clusters or nanocrystalline metallic carbides can be embedded in the carbon network. In this work, a filtered metal plasma cathodic arc technique is used to generate a metal plasma and acetylene is introduced to the metal plasma plume to deposit metal-containing DLC (Me-DLC) films and form nanocrystalline carbide phases in the amorphous carbon matrix. The films exhibit high thermal stability up to annealing temperatures of 500 °C as revealed by X-ray diffraction, transmission electron microscopy, and Raman spectroscopy. At treatment temperature over 500 °C, a large amount of hydrogen is lost from the Me-DLC films as shown by elastic recoil detection. Breakdown and structural collapse of the film at high temperature can be attributed to the breaking of C–H bonds. Consequently, the C–C networks become more graphite-like to facilitate the formation of volatile C–O and metal oxides phases.     

POWER OPTIMIZATION OF FINITE STATE MACHINE BASED ON GENETIC ALGORITHM

Using state assignment to minimize power dissipation and area for finite state machines is computationally hard.Most of published results show that the reduction of switching activity often trades with area penalty.In this paper,a new approach is proposed.Experimental results show a significant reduction of switching activity without area penalty compared with previous publications.     

提高延迟焦化装置苛刻度的探索

介绍了镇海炼化延迟焦化装置为提高苛刻度所采取的降低循环比、缩短生焦时间、提高加热炉出口温度等措施情况。实施降低循环比的措施后,液体产品收率增加了1.96%,焦炭收率下降了1.7%,处理量提高了4.7%。缩短生焦周期后,Ⅰ、Ⅱ套焦化装置的处理量分别提高了6.2%、7.2%。同时,炉出口温度需根据不同的原料油性质和不同的产品要求来确定。对于炉管烧焦周期,应以经济性为原则,科学权衡利弊后确定。介绍了加强除焦、行车设备维护保养所采取的一些措施。     

高等院校贷款的规模控制

我国高等教育事业发展受到资金短缺制约,高等院校金融贷款成为资金来源多渠道化之一。本文就高校取得金融机构资金支持的可行性,高等院校利用信贷资金规模控制提出笔者个人看法,认为高等教育的发展使得高校利用金融机构贷款具有现实可能性;信贷资金规模控制需要合适的财务指标体系来控制。     

A Method of Combined SHPB Technique and BP Neural Network to Study Impact Response of Materials

Abstract:  A new method combining the split Hopkinson pressure bar (SHPB) technique with the back-propagation (BP) neural network program is proposed. By this method, the treated strain wave signals become smooth with less noises induced by the transverse inertia. Moreover, the dynamic rate-dependent constitutive behaviour of materials can be identified, without any pre-assumption of a constitutive model. It is found that by taking the experimentally measured data of strain, strain rate and time as 'input' and the corresponding data of stress as 'output' of the BP neural network, the dynamic constitutive behaviour with internal damage or phase transformation evolution is easy to be identified, where the time could represent either the internal damage evolution or phase transformation process accompanied with the deformation process. It is emphasised that the data learnt by the BP neural network must include both loading and unloading processes, if the whole loading and unloading response is to be correctly predicted. The comparisons between the predictions and experimental results are in good agreement for both polyamide (PA) polymer (as an example of nonlinear viscoelastic materials) and Ti–Ni alloy (as an example of superelastic materials with stress-induced phase transformation).     

当前宁波地区住宅产品可持续发展浅析

文章从居住社区的规划设计和建筑设计两方面以低能耗的角度分析了城市居住功能的分布、社区住宅建筑布局的合理性、社区景观设置的合理性以及停车、中水处理与被动式太阳能住宅建筑的相关先进生态理念,希望通过居住社区的生态可持续性设计改善社区的舒适性和能源的可持续性.     

高性能磁性液体材料研究进展

解决纳米磁性粒子的耐氧化问题对制备高性能磁性液体具有重要意义。系统介绍了金属磁性液体和氮化铁磁性液体的制备方法，并对各种制备方法进行了评述。综述了磁性液体的耐氧化研究进展，主要是纳米金属粒子的无机物包覆和氮化铁磁性液体的抗氧化剂添加；展望了高性能磁性液体在耐氧化方面的研究趋势。