The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area betw...The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine chain is fatigue wear, and its failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. In addition, the material, hot-treatment method and shaping technique for roller have a great influence upon the resistance to multi-impact. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technique are the effective method to increase its resistance to multi-impact.展开更多
An electrochemical immunosensor was developed for sensitive assay ofE. coli in urban sludge, in which electron mediator-mediated enzymatic catalysis and gold nanoparticles（AuNPs） were utilized for signal amplificati...An electrochemical immunosensor was developed for sensitive assay ofE. coli in urban sludge, in which electron mediator-mediated enzymatic catalysis and gold nanoparticles（AuNPs） were utilized for signal amplification. The immnuosensing platform chitosan-thionine（chit-thio）/poly（amidoamine） dendrimer-encapsulated AuNPs [PAMAM（Au）] composites were first prepared from chit-thio and PAMAM（Au） using the layer-by-layer method to provide a matrix for high-stability and high-bioactivity bindings of the capture antibody（cAb）. Moreover, the {dAb-AuNPs-HRP} nanoprobes were designed to exploit the amplification effect of the carrier AuNPs due to the loading amounts of horseradish peroxidase（HRP）and the detection antibody（dAb）. The sandwich-type immunoassay was then successfully used to assay E. coli based on the oxidation of thionine as a result of H2O2-induced enzymatic catalytic reaction by HRP. This study presents a powerful tool in electrochemical immunoassay for E. coli detection with rapid response, high-sensitivity and high-specificity, providing a potential new tool for feasibility assessment of sludge recycle.展开更多
基金This project is supported by National Innovation Foundation for TechnologyBased Firms, China (No.01C26213300872).
文摘The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine chain is fatigue wear, and its failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. In addition, the material, hot-treatment method and shaping technique for roller have a great influence upon the resistance to multi-impact. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technique are the effective method to increase its resistance to multi-impact.
基金Supported by the National Natural Science Foundation of China（Nos.21205051, 51608235） and the Key Project of the Ministry of Education of China（No.210078）.
文摘An electrochemical immunosensor was developed for sensitive assay ofE. coli in urban sludge, in which electron mediator-mediated enzymatic catalysis and gold nanoparticles（AuNPs） were utilized for signal amplification. The immnuosensing platform chitosan-thionine（chit-thio）/poly（amidoamine） dendrimer-encapsulated AuNPs [PAMAM（Au）] composites were first prepared from chit-thio and PAMAM（Au） using the layer-by-layer method to provide a matrix for high-stability and high-bioactivity bindings of the capture antibody（cAb）. Moreover, the {dAb-AuNPs-HRP} nanoprobes were designed to exploit the amplification effect of the carrier AuNPs due to the loading amounts of horseradish peroxidase（HRP）and the detection antibody（dAb）. The sandwich-type immunoassay was then successfully used to assay E. coli based on the oxidation of thionine as a result of H2O2-induced enzymatic catalytic reaction by HRP. This study presents a powerful tool in electrochemical immunoassay for E. coli detection with rapid response, high-sensitivity and high-specificity, providing a potential new tool for feasibility assessment of sludge recycle.
