Papers by Author: Jian Li

Abstract: Nowadays, the event-related potential (ERP)-based spelling device, often referred to as P300-Speller, is the most popular Brain-computer interface (BCI) which can provide a new communication path between patients suffered amyotrophic lateral sclerosis (ALS) with the outside world. At present, there are various P300 paradigms for P300-Speller, but no matter the accuracy or the speed cannot be supplied in our daily life. In this paper, an experiment based the two paradigms was proposed and operated to figure out which paradigm is much better between single display (SD) paradigm and region-based (RB) paradigm. 5 naive subjects participated the experiment and concluded that SD-Speller is superior to RB-Speller when the ISI was set 150ms. This result provides relevant theoretical basis for designing better graphical interface based on BCI.

Abstract: When the self-made with Teflon lined with stainless steel reaction kettle is used to produce PbTiO₃ nanowires with the adoption of hydrothermal reaction , PbTiO₃ nanowires with new structure can be made when Pb/Ti equals 2.2. Observed through the Transmission Electron Microscopy (TEM), the bending feature of the PbTiO₃ nanowires can be observed for several times when X-ray diffraction (XRD) and Electron Backscattered Diffraction (EBSD) are used to analyse and test the crystal structure of the nanowires. The result of the study shows that the degree of the bending of the PbTiO₃ nanowires varies with the intensity of the electron beam from the Transmission Electron Microscopy, and its process can be reversible.

Abstract: The FeMnCrNi/Cr₃C₂ inter metallic composite coatings are prepared by high velocity arc spraying (HVAS) technology on 20G steel. The properties, such as the microstructure, micro hardness, binding strength, high temperature oxidation, thermal shock resistance, and erosion in high temperature, are studied based on methods such as analysis of optical microscope, micro hardness, field emission scanning electron microscope (FESEM), and spectrum analysis. The result shows that FeMnCrNiAl/Cr₃ C₂ coatings, compared with 20G steel substrate, present higher micro hardness, binding strength and more excellent high temperature properties, which will be improved if added with rare-earth Alloy.

Abstract: The corrosion behavior of titanium in hydrogen peroxide solutions was studied by measuring the titanium ions concentration using spectrophotometer. The influence of additives (K+ ， Ca2+ ，Na+ ，Mg2+ ，Cl- ，HPO4 2-, H2PO4 - ) on the corrosion behavior of titanium was examined. The results indicated that Ca2+ exhibited the highest inhibition to the titanium corrosion in hydrogen peroxide solutions, while HPO4 2- behaved as an accelerator to the corrosion. It was suggested that the Ca2+ was absorbed on the titanium surface to form a thin film of CaTiO3 or CaO2, and consequently, inhibited the corrosion of titanium. The acceleration of the titanium corrosion in the present of HPO4 2- was caused probably by the increased defect of surface oxide films after absorption of HPO4 2- ions.