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Meng P.,Zhejiang University | Zhang J.,Zhejiang University | Chen H.,Zhejiang University | Qian Z.,Zhejiang University | Shen Y.,Zhejiang Test Academy of Quality and Technical Supervision
Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC | Year: 2011

This paper characterized the CM noise generation and coupling mechanism to predict the CM noise in Flyback converter. The spectrum of noise sources are analyzed using bandwidth-effects-FFT and the CM noise coupling paths are identified to build up a new CM noise analysis method. With this CM noise analysis method, the total CM noise and the contributions of all the coupling paths in the converter can be predicted. The performance of CM noise suppression measures can also be diagnosed before practical implementation. This method can provide EMC designers with a costless and time saving solution to design the converter. Experimental illustrations are also included to verify the validity of the proposed CM noise analysis method. Comparison between the measured and predicted results shows that this CM noise modeling method can provide adequate prediction of the CM noise feature for the converter. © 2011 IEEE.

Ding H.,Zhejiang Test Academy of Quality and Technical Supervision | Guo L.,Zhejiang Sci-Tech University
Applied Mechanics and Materials | Year: 2013

Compared with double-sided permanent magnet linear synchronous motors(DPMLSM) with long secondary, the short secondary construction also has advantages of high dynamic performance and stable thrust, and is more suitable for the aspect of long-term acceleration. In this paper, magnetic field and characteristic of two different moving-magnet-type double-sided linear synchronous motors were analyzed by using 2D finite element method(FEM). The internal and external permanent magnet motor constructions with the same NdFeB and windings were compared according to flux density and electrical force. It was inferred that internal PM motors can provide the same force with lighter secondary weight and faster response speed. © (2013) Trans Tech Publications, Switzerland.

Mao D.,Anhui University of Science and Technology | Li T.,Anhui University of Science and Technology | Liu H.,Anhui University of Science and Technology | Li Z.,Anhui University of Science and Technology | And 2 more authors.
Colloid and Polymer Science | Year: 2013

PolyHIPEs are highly porous, crosslinked polymer foams typically synthesized within high internal-phase emulsions (HIPEs). Two kinds of polyHIPEs including poly(styrene-divinylbenzene) [P(St-DVB)] and poly(methyl methacrylate-divinylbenzene) [P(MMA-DVB)] foams are synthesized in this work, which are fabricated from HIPEs template via radiation-induced polymerization at room temperature. Traditional free radical polymerization initiated by potassium peroxydisulfate (KPS) at 60 C for producing polyHIPE P(St-DVB) foams is also conducted for comparison. It is found that the amount of emulsifier can be reduced greatly in the radiation-induced polymerization of HIPEs at room temperature, compared with the traditional polymerization approach. Besides, P(MMA-DVB) PolyHIPE foams with a fine microstructure of highly interconnected pores have been successfully fabricated via radiation-induced polymerization in this work, which is usually difficult to be prepared by thermal-initiation method because of the intermediate hydrophobicity of methyl methacrylate monomer. The influences of the fraction of internal aqueous phase and the concentration of emulsifier on the structure and performance of foams are carefully explored. The structure and compression strength of the foams are characterized by scanning electron microscopy and a mechanical testing machine, respectively. [Figure not available: see fulltext.] © 2013 Springer-Verlag Berlin Heidelberg.

Wang X.,Zhejiang Test Academy of Quality and Technical Supervision
Materials Research Bulletin | Year: 2012

Uniform α-Fe 2O 3 particles of different shapes have been synthesized through hydrothermal process. The additives, the type of Fe(III) salts and reaction conditions in hydrothermal process were thoroughly investigated. The crystalline structure and morphology of the as-synthesized powder have been characterized by using X-ray powder diffraction, scanning electron microscopy and field emission scanning electron microscopy. Rod and ellipsoidal-shaped α-Fe 2O 3 were obtained with ferric chloride as a precursor, while only irregular-shaped particles were synthesized by using ferric nitrate as precursors in the absence of NH 4OH. Direct transformation of micro-rod hematite to ellipsoidal particles with FeCl 3 as precursor was also observed by adding NH 4OH. It is shown that the nanorod was formed through presumed directional aggregation of rapidly formed nucleus, while the formation of ellipsoidal hematite particles may undergo a nucleation-aggregation-dissolution-recrystallization process in the presence of ammonium. © 2012 Elsevier Ltd.

Wang S.,Zhejiang University | Xu H.,Environmental Science Research and Design Institute of Zhejiang Province | Yao P.,Zhejiang Test Academy of Quality and Technical Supervision | Chen X.,Zhejiang University
Electrochemistry | Year: 2012

Seawater can be used as an electrolyte for Cl 2 evolution, and proper selection of electrode materials is of great importance. In this paper, a new type of dimensionally stable anodes, Ti/RuO 2-IrO 2-Sb 2O 5-SnO 2, was investigated for Cl 2 evolution from seawater. The physicochemical and electrochemical properties were examined, and the electrocatalytic activity for Cl 2 evolution was measured under different conditions. It was shown that the RuO 2-IrO 2Sb 2O 5-SnO 2 coating was compact in microstructure. The current efficiency was 71.2-86.7%, depending on the operational conditions. The anodes were predicted to be able to work effectively for over 6 years at a current density of 1500Am -2 for seawater electrolysis. © The Electrochemical Society of Japan All rights reserved.

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