Papers by Author: Jan Yong Wang

Abstract: The primary aim pursued by the preparation of the separation membrane is to make the membrane thinner as well as have no defects. The field-flow fractionation deposition is a new molding technology which can overcome the traditional disadvantages, such as multi-preparation, to the preparation of a great area of the separation membrane with no defects. Therefore the main ingredients which influence the appearance and performance of titanium membrane layers are investigated by a scanning electricity mirror (SEM) as well as a porous material testing instrument: powder performance prepared and confected; selection of supporting body; sintering system such as temperature and time. It is shown that the membrane thickness can be controlled at 50μm or so.

Abstract: Green machining fluids of oil-filmed water-droplets (OW) can be produced by means of combined mist-jet with cooled air, minimum naturally dissoluble oils (botanic or ester oils) and little water, which are beneficial to realize zero-emission machining and thoroughly eliminate the influences of the conventional water-miscible machining fluids on the operators’ health and the eco-environments as well as save energy consumption and lower in production costs. In this study, grinding performances and mechanism analyses of green machining fluids are investigated by comparison to the conventional ones such as emulsion flood coolant on the plane NC grinder. The investigations have further shown that green machining fluids can improve grinding quality in comparison with emulsion flood coolant due to good lubrication and cooling effects, which are applicable to many situations of machining processes.

Abstract: The failure of individual multiwall carbon nanotubes (CNTs) during electron field emission was investigated in situ inside the transmission electron microscope (TEM). Long time emission of a single CNT at the level of tens µA or higher may lead to unrecoverable damage to the CNT. High-resolution TEM observations of the emission failure process shown that the failure was usually companied by structure damage or break of the CNT, and the failure or degradation of the emission characteristics of the CNT was typically initiated at the CNT/substrate contact, defect site or at the open end via the field evaporation or oxidation of the tip of the CNT.