The 3-D thermo-mechanical coupled elasto-plastic finite element method (FEM)was used for the simulation of the two-pass continuous hot rolling process of 60SiMnA spring steelbars and rods using MARC/AutoForge3.1 softw...The 3-D thermo-mechanical coupled elasto-plastic finite element method (FEM)was used for the simulation of the two-pass continuous hot rolling process of 60SiMnA spring steelbars and rods using MARC/AutoForge3.1 software. The simulated results visualize the metal flow andthe dynamic evolutions of the strain, stress and temperature during the continuous hot rolling,especially inside the work-piece. It is shown that the non-uniform distributions of the strain,stress and temperature on the longitudinal and transverse sections are a distinct characteristic ofthe continuous hot rolling, which can be used as basic data for improving the tool design,predicting and controlling the micro-structural evolution of a bar and rod.展开更多
A method for the analysis of trace polycyclic aromatic hydrocarbons（PAHs） in aqueous samples has been established by polydimethylsiloxane（PDMS） rod aided stir bar sorptive extraction（SBSE）. The homemade PDMS rod...A method for the analysis of trace polycyclic aromatic hydrocarbons（PAHs） in aqueous samples has been established by polydimethylsiloxane（PDMS） rod aided stir bar sorptive extraction（SBSE）. The homemade PDMS rod has a size of 30 mm×3 mm o.d. with a volume of ca. 200 μL, stable in thermal desorption process. The enriched PAHs by the PDMS rod were released in a homemade thermal desorption system coupled with gas chromatography. Experimental parameters for extraction of six PAHs were optimized including extraction time, pH, ionic strength and temperature of solution. The procedure has good recoveries of 80.0%―100.3% and very low limits of detection of 4.0―33 ng/L. PAHs in rain and river water were analyzed by this method.展开更多
文摘The 3-D thermo-mechanical coupled elasto-plastic finite element method (FEM)was used for the simulation of the two-pass continuous hot rolling process of 60SiMnA spring steelbars and rods using MARC/AutoForge3.1 software. The simulated results visualize the metal flow andthe dynamic evolutions of the strain, stress and temperature during the continuous hot rolling,especially inside the work-piece. It is shown that the non-uniform distributions of the strain,stress and temperature on the longitudinal and transverse sections are a distinct characteristic ofthe continuous hot rolling, which can be used as basic data for improving the tool design,predicting and controlling the micro-structural evolution of a bar and rod.
基金Supported by the Natural Science Foundation of Shandong Province, China(No.ZR2010BM035)
文摘A method for the analysis of trace polycyclic aromatic hydrocarbons（PAHs） in aqueous samples has been established by polydimethylsiloxane（PDMS） rod aided stir bar sorptive extraction（SBSE）. The homemade PDMS rod has a size of 30 mm×3 mm o.d. with a volume of ca. 200 μL, stable in thermal desorption process. The enriched PAHs by the PDMS rod were released in a homemade thermal desorption system coupled with gas chromatography. Experimental parameters for extraction of six PAHs were optimized including extraction time, pH, ionic strength and temperature of solution. The procedure has good recoveries of 80.0%―100.3% and very low limits of detection of 4.0―33 ng/L. PAHs in rain and river water were analyzed by this method.
