The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investiga...The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects.展开更多
In this study,an enzyme 1linked immunosorbent assay(ELISA)was established to detect beef and 1amb components,and its performance was tested.Double-antibody sandwich ELISA was adopted and determined a coating concentra...In this study,an enzyme 1linked immunosorbent assay(ELISA)was established to detect beef and 1amb components,and its performance was tested.Double-antibody sandwich ELISA was adopted and determined a coating concentration of capture antibody 3G5 of 1:4000,a working concentration of enzyme-labeled antibody 2E7-horseradish peroxidase(HRP)of 1:1000,a sample incubation time of 60 min and a detection antibody reaction time of 60 min.The specificity,sensitivity,repeatability and stability of this assay were detemmined.The limit of detection for beef and 1amb skeleta1 muscle troponin I was 45 mg/kg,the inter-assay and intra-assay recovery rates ranged from 80.4%to 115.7%,the coefficients of variation were below 13.6%,and the cIoss reaction rates of the tissue components of chicken,duck and fish were below 13.4%.The sandwich ELISA method established in this study is stable and has high accuracy.The test results were consistent with the polymerase chain reaction(PCR)method at 50 and 100 g/kg-Therefore,this ELISA method can be used to quantitatively detect beef and 1amb components in meat products.展开更多
基金funded by the NationalNatural Science Foundation of China (Nos.11902229,11502181)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant Nos.XDB22040502,XDC06030200).
文摘The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects.
基金This research was funded by Hebei Provincial Department of Science and Technology(21375501D)the Hebei Academy of Sciences(2019Q01).
文摘In this study,an enzyme 1linked immunosorbent assay(ELISA)was established to detect beef and 1amb components,and its performance was tested.Double-antibody sandwich ELISA was adopted and determined a coating concentration of capture antibody 3G5 of 1:4000,a working concentration of enzyme-labeled antibody 2E7-horseradish peroxidase(HRP)of 1:1000,a sample incubation time of 60 min and a detection antibody reaction time of 60 min.The specificity,sensitivity,repeatability and stability of this assay were detemmined.The limit of detection for beef and 1amb skeleta1 muscle troponin I was 45 mg/kg,the inter-assay and intra-assay recovery rates ranged from 80.4%to 115.7%,the coefficients of variation were below 13.6%,and the cIoss reaction rates of the tissue components of chicken,duck and fish were below 13.4%.The sandwich ELISA method established in this study is stable and has high accuracy.The test results were consistent with the polymerase chain reaction(PCR)method at 50 and 100 g/kg-Therefore,this ELISA method can be used to quantitatively detect beef and 1amb components in meat products.