Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa...Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.展开更多
The strength of non-heat-treatable 5xxx Al alloys is derived from solid solution strengthening and strain hardening,the absence of a precipitation strengthening response results in their lower strength.In this study,s...The strength of non-heat-treatable 5xxx Al alloys is derived from solid solution strengthening and strain hardening,the absence of a precipitation strengthening response results in their lower strength.In this study,significant improvements in strength can be achieved by subjecting three different Mg concen-trations 5xxx Al alloys to cyclic plasticity.A quantitative analysis of the respective contributions to the yield strength has been conducted by combining transmission electron microscopy and atom probe to-mography.Additionally,the fatigue performance and fatigue mechanism of the cyclic strengthened 5xxx Al alloys have been thoroughly studied due to its transformation from non-heat-treatable to precipitation strengthening.We demonstrate that the high-cycle fatigue(HCF)strength of the cyclically strengthened state only experiences a minor improvement compared to the as-received state,which is significantly dis-proportionate to the enhancement in tensile strength.This disparity is primarily attributed to the changes in microstructure and fatigue mechanisms,resulting in a reduction in fatigue ratio.This study provides important insights for expanding research on cyclic plasticity methods in fatigue performance,and can aid in the development of improved processes for optimal fatigue resistance.展开更多
The gut pathogen Enterocloster bolteae(E.bolteae)has been associated with autism spectrum disorder(ASD).The development of an E.bolteae vaccine to prevent gastrointestinal diseases,might be beneficial for understandin...The gut pathogen Enterocloster bolteae(E.bolteae)has been associated with autism spectrum disorder(ASD).The development of an E.bolteae vaccine to prevent gastrointestinal diseases,might be beneficial for understanding and treating ASD.Capsular polysaccharide(CPS)is a major virulence factor for E.bolteae.Based on an antigenicity evaluation of oligosaccharides associated with E.bolteae CPS and a structural revision of this carbohydrate antigen,two series of glycans including the D-Manp-D-Rhap type oligosaccharides 13-18 and the D-Ribp-D-Rhap type disaccharides 19-23 related to E.bolteae WAL-16351 CPS were prepared.The hydrogen-bond mediated glycosylation and conformational locking strategy facilitated the constructions of two 1,2-cis-β-glycosidic linkages.Glycan microarray analysis revealed that oligosaccharides 4,5,and 19 are recognized by antibodies in the anti-E.bolteae sera.The sera IgG antibodies induced by glycoconjugate 19-CRM197 recognize the CPS and bacteria specifically,whereas the IgG antibodies induced respectively by glycoconjugates 4-CRM197 and 5-CRM197 showed almost no binding to the CPS and bacteria.These results indicated that disaccharide 19 is a potential candidate for the development of E.bolteae vaccines.展开更多
The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to cont...The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan （PC6） with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy.展开更多
基金financial support of the National Natural Science Foundation of China(No.52371103)the Fundamental Research Funds for the Central Universities,China(No.2242023K40028)+1 种基金the Open Research Fund of Jiangsu Key Laboratory for Advanced Metallic Materials,China(No.AMM2023B01).financial support of the Research Fund of Shihezi Key Laboratory of AluminumBased Advanced Materials,China(No.2023PT02)financial support of Guangdong Province Science and Technology Major Project,China(No.2021B0301030005)。
文摘Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%.
基金the National Natural Science Foundation of China(No.52371103)the Fundamental Research Funds for the Central Universities(No.2242023K40028).
文摘The strength of non-heat-treatable 5xxx Al alloys is derived from solid solution strengthening and strain hardening,the absence of a precipitation strengthening response results in their lower strength.In this study,significant improvements in strength can be achieved by subjecting three different Mg concen-trations 5xxx Al alloys to cyclic plasticity.A quantitative analysis of the respective contributions to the yield strength has been conducted by combining transmission electron microscopy and atom probe to-mography.Additionally,the fatigue performance and fatigue mechanism of the cyclic strengthened 5xxx Al alloys have been thoroughly studied due to its transformation from non-heat-treatable to precipitation strengthening.We demonstrate that the high-cycle fatigue(HCF)strength of the cyclically strengthened state only experiences a minor improvement compared to the as-received state,which is significantly dis-proportionate to the enhancement in tensile strength.This disparity is primarily attributed to the changes in microstructure and fatigue mechanisms,resulting in a reduction in fatigue ratio.This study provides important insights for expanding research on cyclic plasticity methods in fatigue performance,and can aid in the development of improved processes for optimal fatigue resistance.
基金the National Natural Science Foundation of China(Nos.22325803,22277042,22177041,22207042,22107037)the Max Planck Society International Partner Group Program,the China Scholarship Council(CSC)the Fundamental Research Funds for the Central Universities for funding。
文摘The gut pathogen Enterocloster bolteae(E.bolteae)has been associated with autism spectrum disorder(ASD).The development of an E.bolteae vaccine to prevent gastrointestinal diseases,might be beneficial for understanding and treating ASD.Capsular polysaccharide(CPS)is a major virulence factor for E.bolteae.Based on an antigenicity evaluation of oligosaccharides associated with E.bolteae CPS and a structural revision of this carbohydrate antigen,two series of glycans including the D-Manp-D-Rhap type oligosaccharides 13-18 and the D-Ribp-D-Rhap type disaccharides 19-23 related to E.bolteae WAL-16351 CPS were prepared.The hydrogen-bond mediated glycosylation and conformational locking strategy facilitated the constructions of two 1,2-cis-β-glycosidic linkages.Glycan microarray analysis revealed that oligosaccharides 4,5,and 19 are recognized by antibodies in the anti-E.bolteae sera.The sera IgG antibodies induced by glycoconjugate 19-CRM197 recognize the CPS and bacteria specifically,whereas the IgG antibodies induced respectively by glycoconjugates 4-CRM197 and 5-CRM197 showed almost no binding to the CPS and bacteria.These results indicated that disaccharide 19 is a potential candidate for the development of E.bolteae vaccines.
基金funded by Development Plan(973 Plan) of National Critical and Basic Research,No.2012CB518505,2010CB530500,2006CB504504
文摘The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan （PC6） with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy.
