Search

Your search keyword '"Wang, Zhengbin"' showing total 181 results
Start Over Author "Wang, Zhengbin"
181 results on '"Wang, Zhengbin"'

16. Polarization modulation by tunable electromagnetic metamaterial reflector/absorber

Author

Zhu, Bo, Zhao, Yijun Feng Junming, Huang, Ci, Wang, Zhengbin, and Jiang, Tian

Subjects
Physics - Optics
Abstract

We propose a polarization modulation scheme of electromagnetic (EM) waves through reflection of a tunable metamaterial reflector/absorber. By constructing the metamaterial with resonant unit cells coupled by diodes, we demonstrate that the EM reflections for orthogonal polarized incident waves can be tuned independently by adjusting the bias voltages on the corresponding diodes. Owing to this feature, the reflected EM waves can be electrically controlled to a linear polarization with continuously tunable azimuth angle from 0o to 90o at the resonant frequency, or an elliptical polarization with tunable azimuth angle of the major axis when off the resonant frequency. The proposed property has been verified through both numerical simulations and experimental measurements at microwave band, which enables us to electrically modulate the polarization state of EM waves flexibly., Comment: 8 pages, 4 figures

Published
2010
Full Text
View/download PDF

39. Effect of Impact Angle on the Critical Flow Velocity for Erosion–Corrosion of 304 Stainless Steel in Simulated Sand-Containing Sea Water

Author

Yugui Zheng, Wang Zhengbin, Siyu He, J.Z. Yi, and Hongxiang Hu

Subjects
Momentum (technical analysis), Materials science, 020209 energy, Mechanical Engineering, Materials Science (miscellaneous), Erosion corrosion, Metals and Alloys, 02 engineering and technology, Corrosion, Shear (sheet metal), 020303 mechanical engineering & transports, 0203 mechanical engineering, Mechanics of Materials, Solid mechanics, 0202 electrical engineering, electronic engineering, information engineering, Materials Chemistry, Surface roughness, Composite material, Polarization (electrochemistry), Choked flow
Abstract

The critical flow velocity (CFV) is an important indicator to evaluate the erosion–corrosion performance of passive materials. The study focusing on the effect of impact angles on CFV behavior contributes to the further understanding of the CFV mechanism for erosion–corrosion. In this paper, the CFV behavior for erosion–corrosion of 304 stainless steel at different impact angles was investigated in the simulated sand-containing sea water. The testing methods involve the potentiostatic polarization test, mass loss measurement, surface roughness measurement, and morphology analysis. The results show that the CFV values are 15 m/s for 30°, 13 m/s for 45°, 13 m/s for 60°, and 13 m/s for 90° impact angels, respectively. The variation of CFV values with impact angles depends on the synergistic action between the normal momentum and the shear momentum, which influences the depassivation–repassivation behavior of passive films formed on the metal surface. With the increase of the impact angle, the dominant erosion–corrosion mechanism converts from the micro-cutting to the plastic deformation mechanism.

Published
2021

45. Electrochemical and surface analytical studies of transition metal bipyridine dicarboxylic acid complexes as corrosion inhibitors for a mild steel in HCl solution.

Author

Liu, Xia, Sun, Yue, Lu, Meiheng, Pan, Xuemei, and Wang, Zhengbin

Subjects
MILD steel, DICARBOXYLIC acids, TRANSITION metals, ELECTROLYTIC corrosion, X-ray photoelectron spectroscopy, TRANSITION metal complexes, BIPYRIDINE
Abstract

The 2,2′-bipyridine-3,3′-dicarboxylic acid (bpda) and its transition metal complexes including Ni(bpda)2, Zn(bpda)2 and Mn(bpda)2, were synthesized and tested as corrosion inhibitors for a carbon steel in 0.5 M HCl solution by electrochemical tests and surface analyses. The electrochemical results indicate that the inhibition efficiencies increase with the concentration of corrosion inhibitors. The complexes exhibit higher inhibition efficiencies compared to the bpda ligand, among which Ni(bpda)2 is the most effective for inhibiting corrosion. The corrosion morphology observation further evidences the superior corrosion inhibition performance of the three complexes. Fourier transform infrared and X-ray photoelectron spectroscopy analyses confirm the spontaneous adsorption of all four inhibitors on the steel surface, and the adsorption analysis suggests a combined physisorption and chemisorption mechanism. Accordingly, the superior corrosion inhibition performance of the three complexes could be attributed to their good adsorption abilities. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results