Search

Your search keyword '"Yang, Fei"' showing total 39 results
Start Over Author "Yang, Fei" Journal applied mechanics and materials
39 results on '"Yang, Fei"'

37. Study on Thermal Degradation of Phenolic Resin

Author

Yang Fei Chen, Hong Bo Liu, and Zhi Qin Chen

Subjects
Thermogravimetric analysis, Formaldehyde, Ether, General Medicine, Cresol, chemistry.chemical_compound, chemistry, medicine, Phenol, Hydroxymethyl, Methylene, Chemical decomposition, Nuclear chemistry, medicine.drug
Abstract

The thermal degradation of phenolic formaldehyde resins (PF) were studied using thermo gravimetric analysis (TGA). The evolved volatiles during thermal degradation of PF were examined by mass spectrometry (MS). The structure changes of thermal degradation of synthetical phenolic resin (PF1.2) and commercial resin (CPF) were investigated by solid-state 13C nuclear magnetic resonance (13C-NMR) techniques. The experimental results show that the degradation process of PF could be separated into three stages. In the first stage, ether bonds and unreacted terminal hydroxymethyl groups of the cured resin degraded. Methylene bridges decomposed into methyl groups then yielded both phenol and cresol homolog in the second stage. In the third stage, cyclodehydration and forming char of phenolic hydroxyl occurred. Our study showed that the main thermal degradation of PF in the second stage is the decomposition reaction of the methylene bridges instead of auto-oxidation of the methylene bridges reported in previous works.

Published
2013

38. Empirical Analysis on Aerobics Multimedia Teaching Based on Interactive Mode

Author

Yang Fei, Hua Zhao, and Chao Li

Subjects
Class (computer programming), Scope (project management), Multimedia, Computer science, business.industry, Information technology, General Medicine, computer.software_genre, Code (semiotics), Field (computer science), Traditional education, Mode (computer interface), Data envelopment analysis, ComputingMilieux_COMPUTERSANDEDUCATION, business, computer
Abstract

With the increasing development of information technology, the scope of the application of multimedia technology is more and more widely. The application of multimedia technology in teaching has become more and more mature, which has formed a complementary relationship with traditional education. But the application of modern multimedia technology in the physical teaching is relatively lag, which has become one of the urgent problems to be solved in this field. Based on the characteristics of the integration of inside and outside class teaching and multimedia technology, it constructs the multimedia system of the integration of inside and outside class teaching. According to the aerobics rhythm continuity characteristics, the spatial discretization code of the interlaced scanning image makes the integration of inside and outside class of aerobics teaching of mutual learning come true. And it applies the data envelopment analysis to make experiment exploratory empirical analysis on the whole teaching system, which can be able to provide scientific support for modern education and teaching with positive feedback nature of the teaching advantages.

Published
2013

39. On the Numerical Study of Bubbly Flow Created by Ventilated Cavity

Author

Sherman C.P. Cheung, Min Xiang, Wei Hua Zhang, Yang Fei, and Jiyuan Tu

Subjects
Physics, education.field_of_study, business.industry, Bubble, Population, Base (geometry), Phase (waves), General Medicine, Mechanics, Computational fluid dynamics, Pipe flow, Physics::Fluid Dynamics, Flow (mathematics), Porosity, education, business, Simulation
Abstract

The aim of the study was to develop a numerical model to reproduce the bubbly flow field created by ventilated cavity which includes three different regions. The model was established based on the Eulerian-Eulerian two-fluid model coupled with a population balance approach which is solved by the Homogeneous Multiple-Size-Group (MUSIG) model to predict bubble size distribution. Base on the model, the simulation was carried out at the experimental condition of Su et al. (1995). Firstly three regions were successfully captured proved by the spatial voidage distribution and streamline shape. Then distributions of void fraction and Sauter mean bubble diameter at various sections below the cavity corresponding to three regions respectively were plotted against experimental data. A close agreement was observed in the void fraction distribution which indicates that qualitative details of the structure of the two-phase flow field below the cavity was successfully produced. The Sauter mean bubble diameter in the pipe flow region was under-predicted for about 10%. In conclusion, the proposed model was validated in predicting the multi-region flow field below the ventilated cavity which will provide a valuable insight in designing and controlling of the two phase systems with the detailed flow field information obtained.

Published
2010

Catalog

Books, media, physical & digital resources
See catalog results