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Effect of sulfate-reducing bacteria on corrosion of X80 pipeline steel under disbonded coating in a red soil solution

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Journal of Materials Science & Technology 2021年第28期87卷 1-17页

作者： Boxin wei Jin Xu Qi Fua Qingyu Qin Yunlong Bai Cheng Sun chuan wang zhenyao wang wei ke Liaoning Shenyang Soil and Atmosphere Material Corrosion National Observation and Research Station Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

Effect of sulfate-reducing bacteria on the corrosion behaviors of API-X80 pipeline steel has been studied in crevices under simulated disbonded coatings in red soil *** results show that there are amounts of SRB in the crevice under the simulated disbonded coating in the red soil solution during the whole period of *** electrochemical impedance spectroscopy shows that SRB can enhance the corrosion of the steel in the crevice under the simulated disbonded coating,and the thermodynamic analyses indicate that SRB can accelerate the corrosion of steel using not only sulfate but also ferric hydroxide as electron acceptors.

关键词： Sulfate-reducing bacteria influenced corrosion Disbonded coating Red soils X80 pipeline steel EIS

Atmospheric Corrosion of Copper Exposed in a Simulated Coastal-Industrial Atmosphere

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Journal of Materials Science & Technology 2017年第6期33卷 587-595页

作者： Chen Pan wangyan Lv zhenyao wang wei Su chuan wang Shinian Liu Environmental Corrosion Center Institute of Metal Research Chinese Academy of Sciences Electric Power Research Institute Guangdong Power Grid Corporation

The corrosion behavior of copper exposed in a simulated coastal-industrial atmosphere has been investigated using weight loss measurement, scanning electron microscopy, X-ray diffraction, potentiodynamic polarization and in-situ electrochemical impedance spectroscopy（EIS） with micro-distance *** results show that corrosion kinetics follows the empirical equation D = Atn. The main corrosion products are composed of Cu_2O, Cu_2Cl（OH）_3 and Cu_4Cl_2（OH）_6. A two-layer structure comprising a loose outer layer and a compact inner layer forms the corrosion products during corrosion process. SO_2 has been found to promote the formation of Cu_4Cl_2（OH）_6.

关键词： Copper Atmospheric corrosion SEM EIS

Effects of UV on the Corrosion Behavior of Pure Aluminum 1060 in Simulated Nansha Marine Atmosphere

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Acta Metallurgica Sinica(English Letters) 2022年第7期35卷 1207-1220页

作者： Can Peng Mingxiao Guo Tianzhen Gu Xiaohan Li chuan wang zhenyao wang Cheng Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Liaoning Shenyang Soil and Atmosphere Corrosion of Material National Observation and Research Station Shenyang 110016China

The corrosion behavior of pure aluminum 1060 subjected to a wet-dry cyclic accelerated test in simulated Nansha marine atmosphere in the dark and under UV illumination has been investigated by means of scanning electron microscopy(SEM),electrochemical impedance spectroscopy(EIS),and Mott–Schottky measurements in this *** results show that under the two conditions,the native oxide films are constantly destroyed and the thicknesses of the oxide films continuously decrease in the first 24 days of the corrosion *** particular,UV illumination can diminish the pitting corrosion susceptibility of the native oxide films to an extent in terms of a photo-induced modifi cation of the native oxide film on the pure aluminum ***,UV illumination can also reduce the carrier concentration in the oxide films,thus reducing the conductivity and the corrosion rate.

关键词： Aluminum Atmospheric corrosion UV illumination Electrochemical impedance spectroscopy

Enhancement of subgap conductance in a graphene superconductor junction by valley polarization

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Chinese Physics B 2017年第2期26卷 428-434页

作者： chuan-Xin Li Sa-ke wang Jun wang College of Mathematics and Physics Jingchu University of Technology Jingmen 448000 China Department of Physics Southeast University Nanjing 210096 China

we theoretically study the differential conductance of a graphene/graphene superconductor junction, where the valley polarization of Dirac electrons is considered in the nonsuperconducting region. It is shown that the subgap conductance will increase monotonically with the valley-polarization strength when the chemical potential μ is near the Dirac point μ≤ 3？（？ is the superconducting gap）, whereas it will decrease monotonically when μ is far away from the Dirac point, μ≥ 5？.The former case is induced by the specular Andreev reflection while the retro-reflection accounts for the later result. Our findings may shed light on the control of conductance of a graphene superconductor junction by valley polarization.

关键词： graphene valley polarization subgap conductance specular Andreev reflection

Multi-branch query tree protocol for solving RFID tag collision problem

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 51-54页

作者： JIAO chuan-hai wang ke-ren Laboratory 304 of Communications and Information Systems Electronic Engineering Institute Hefei 230037 China

The technology of anti-collision is a key point in radio frequency identification （RFID） system. To avoid data collision, there are two approaches： ALOHA based algorithm and binary tree （BT） based algorithm. However, these cannot solve the collision problem completely, especially when the tag quantity is big and the tag ID is long. In this article, we present a multi-branch query tree （MBQT） protocol based on balanced incomplete block design （BIBD） code, and use 16-bit vectors derived from the BIBD as query prefix symbols of RFID reader. Compared with the conventional anti-collision algorithm, the theoretic analysis and simulation show that the proposed protocol improves the identification efficiency.

关键词： RFID BIBD MBQT

Nanosecond pulsed laser-assisted modified copper surface structure:Enhanced surface microhardness and microbial corrosion resistance

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Journal of Materials Science & Technology 2022年第12期107卷 111-123页

作者： Boxin wei Jin Xu Liqun Gao Hui Feng Jiajun Wu Cheng Sun zhenyao wang wei ke School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Liaoning Shenyang Soil and Atmosphere Material Corrosion National Observation and Research Station Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China State key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110169China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China

Microbiologically influenced corrosion(MIC) is an unavoidable problem in several industries. Copper(Cu)and its alloys are widely used engineering materials. However, MIC of Cu remains a persistent challenge to their performance and functional lifetime under aggressive environments. This study investigated nanosecond pulsed laser processing(LP), which may enhance the corrosion resistance of Cu. The microstructural evolution and corrosion behavior of LP-Cu in the presence of sulfate-reducing bacteria(SRB) were evaluated. Typical deformation-induced microstructural features of high-density dislocations were analyzed on the top surface of LP-Cu coupon. Electrochemical measurements suggested that LP-Cu coupons exhibited better corrosion resistance in SRB-inoculated solution compared with their original counterpart. The enhanced corrosion resistance by LP primarily resulted from the combined influences of compressive residual stress and work hardening in the surface. However, overlap percentage played a key role in improving corrosion resistance. LP produced optimal corrosion resistance at 50% overlap. Therefore, this study introduces a unique and an option for anticorrosion control in manufacturing processes and potentially implements it onto other materials to improve its microbial corrosion resistance through LP.

关键词： Pure copper Laser processing Microbiologically influenced corrosion Pitting Severe plastic deformation

Cooperative blind spectrum sensing using autocorrelation matrix

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 47-53页

作者： JIAO chuan-hai wang ke-ren MEN Shuo Laboratory 304 of Communications and Information Systems Electronic Engineering Institute Hefei 230037 China College of Electronic Information and Automation Chongqing University of Technology Chongqing 400054 China

To improve the spectrum sensing performance in cognitive radios, a scheme of cooperative blind spectrum sensing based on autocorrelation matrix is proposed. The test statistic is extracted from the autocorrelation matrix of the received signal samples and a bi-threshold hybrid decision scheme is designed for local spectrum sensing. The cognitive radio base station makes a credibility fusion based on the local soft decisions and then takes global fusion combining with the local hard decisions. The proposed method is blind in the sense since it requires no apriori knowledge of the signal and the noise power. Theoretical analysis and computer simulation results show that the proposed method can enhance the spectrum sensing capability.

关键词： cognitive radio spectrum sensing autocorrelation matrix blind detection

Long-term kinematics and mechanism of a deep-seated slow-moving debris slide near Wudongde hydropower station in Southwest China

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Journal of Mountain Science 2018年第2期15卷 364-379页

作者： JIANG Shu wang Yi-feng TANG chuan LIU ke Postdoctoral Research Station China Three Gorges Corporation Beijing 100038 China Wudongde Project Construction Department China Three Gorges Projects Development Co. Ltd Luquan 651500 China State key Laboratory of C-eohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Long-term kinematic research of slow- moving debris slide is rare despite of the widespread global distribution of this kind. This paper presents a study of the kinematics and mechanism of the Jinpingzi debris slide located on the Jinsha river bank in southwest China. This debris slide is known to have a volume of 27×106 ms in active state for at least one century. Field survey and geotechnical investigation were carried out to define the structure of the landslide. The physical and mechanical properties of the landslide materials were obtained by in-situ and laboratory tests. Additionally, surface and subsurface displacements, as well as groundwater level fluctuations, were monitored since 2005. Movement features, especially the response of the landslide movement to rainfall, were analysed. Relationships between resisting forces and driving forces were analysed by using the limit equilibrium method assuming rigid-plastic frictional slip. The results confirmed a viscous comoonent in the long-term continuous movement resulting in the quasioverconsolidated state of the slip zone with higher strength parameters than some other types of slowmoving landslides. Both surface and subsurface displacements showed an advancing pattern by the straight outwardly inclined （rather than gently or reversely inclined） slip zone, which resulted in low resistance to the entire sliding mass. The average surface displacement rate from 2005 to 2016 was estimated to be 0.19-0.87 mm/d. Basal sliding on the silty clay seam accounted for most of the deformation with different degrees of internal deformation in different parts. Rainfall was the predominant factor affecting the kinematics of Jinpingzi landslide while the role of groundwater level, though positive, was not significant. The response of the groundwater level to rainfall infiltration was not apparent. Unlike some shallow slow-moving earth flows or mudslides, whose behaviors are directly related to the phreatic groundwater level, th

关键词： Kinematics Slow-moving debris slide Shear strength Rainfall infiltration Viscouscomponent

Fixed-time stabilization of discontinuous spatiotemporal neural networks with time-varying coefficients via aperiodically switching control

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Science China(Information Sciences) 2023年第5期66卷 182-195页

作者： Xiaofang HU Leimin wang chuan-ke ZHANG Xiongbo WAN Yong HE School of Automation China University of Geosciences Hubei key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education

This paper focuses on the challenge of fixed-time control for spatiotemporal neural networks(SNNs) with discontinuous activations and time-varying coefficients. A novel fixed-time convergence lemma is proposed, which facilitates the handling of time-varying coefficients of SNNs and relaxes the restriction on the non-positive definiteness of the derivative of the Lyapunov function. Besides, a more flexible and economical aperiodically switching control technique is presented to stabilize SNNs within a fixed time,efectively reducing the amount of information transmission and control costs. Under the newly established fixed-time convergence lemma and aperiodically switching controller, many more general algebraic conditions are deduced to ensure the fixed-time stabilization of SNNs. Numerical examples are provided to manifest the validity of the results.

关键词： spatiotemporal neural networks discontinuous activations time-varying coefficients fixed-time stabilization aperiodically switching control