Combined with the characteristics of the distributed-drive electric vehicle and direct yaw moment control,a double-layer structure direct yaw moment controller is designed.The upper additional yaw moment controller is...Combined with the characteristics of the distributed-drive electric vehicle and direct yaw moment control,a double-layer structure direct yaw moment controller is designed.The upper additional yaw moment controller is constructed based on model predictive control.Aiming at minimizing the utilization rate of tire adhesion and constrained by the working characteristics of motor system and brake system,a quadratic programming active set was designed to optimize the distribution of additional yaw moments.The road surface adhesion coefficient has a great impact on the reliability of direct yaw moment control,for which joint observer of vehicle state parameters and road surface parameters is designed by using unscented Kalman filter algorithm,which correlates vehicle state observer and road surface parameter observer to form closed-loop feedback correction.The results show that compared to the“feedforward+feedback”control,the vehicle’s error of yaw rate and sideslip angle by the model predictive control is smaller,which can improve the vehicle stability effectively.In addition,according to the results of the docking road simulation test,the joint observer of vehicle state and road surface parameters can improve the adaptability of the vehicle stability controller to the road conditions with variable adhesion coefficients.展开更多
Because the volatile content of isoamyl alcohol increases sharply on the seventh day of wheat mildew infection,isoamyl alcohol can be used as an early biomarker of wheat mildew infection.Currently,only a few sensors f...Because the volatile content of isoamyl alcohol increases sharply on the seventh day of wheat mildew infection,isoamyl alcohol can be used as an early biomarker of wheat mildew infection.Currently,only a few sensors for isoamyl alcohol detection have been reported,and these sensors still suffer from low sensitivity and poor moisture resistance.Herein,the isoamyl alcohol sensitivity of 5 at%Er@LaFeO_(3)(ELFO)was enhanced by loading Ag nanoparticles on the surface of the ELFO microspheres,while the optimal operating temperature was reduced.The moisture resistance of Ag/ELFO was improved by the incorporation of g-C_(3)N_(4)nanosheets(NSs)on the surface of Ag/ELFO through electrostatic self-assembly.Given the requirements for practical applications in grain granaries,the sensing behavior of a Ag/ELFO-based sensor incorporating g-C_(3)N_(4)NSs at 20%relative humidity(RH)was systematically studied,and the sensor demonstrated excellent repeatability,long-term stability,and superior selectivity(791 at 50 ppm)for isoamyl alcohol with a low limit of detection(LOD=75 ppb).Furthermore,the practical results obtained for wheat at different mildew stages further confirmed the potential of the g-C_(3)N_(4)/Ag/ELFO-based sensor for monitoring the early mildew stage of wheat.This work may offer guidance for enhancing the moisture resistance of gas-sensitive materials through the strategy of employing composite nanomaterials.展开更多
In the early-stage diagnosis of lung cancer,the low-concentration(<5 ppm)volatile organic compounds(VOCs)are extensively identified to be the biomarkers for breath analysis.Herein,the urchin-like sodium(Na)-doped z...In the early-stage diagnosis of lung cancer,the low-concentration(<5 ppm)volatile organic compounds(VOCs)are extensively identified to be the biomarkers for breath analysis.Herein,the urchin-like sodium(Na)-doped zinc oxide(ZnO)nanoneedles were synthesized through a hydrothermal strategy with the addition of different contents of citric acid.The Na-doped ZnO gas sensor with a 3:1 molar ratio of Na^(+)and citric acid showed outstanding sensing properties with an optimal selectivity to various VOCs(formaldehyde(HCOH),isopropanol,acetone,and ammonia)based on working temperature regulation.Specifically,significantly enhanced sensitivity(21.3@5 ppm)compared with pristine ZnO(~7-fold),low limit of detection(LOD)(298 ppb),robust humidity resistance,and long-term stability of formaldehyde sensing performances were obtained,which can be attributed to the formation of a higher concentration of oxygen vacancies(20.98%)and the active electron transitions.Furthermore,the improved sensing mechanism was demonstrated by the exquisite band structure and introduction of the additional acceptor level,which resulted in the narrowed bandgap of ZnO.展开更多
In the assessment of food quality,geranyl acetone plays a crucial role as a volatile organic compound(VOC)biomarker for diverse agricultural products,while the ultralow concentration detection meeting application requ...In the assessment of food quality,geranyl acetone plays a crucial role as a volatile organic compound(VOC)biomarker for diverse agricultural products,while the ultralow concentration detection meeting application requirements has been barely studied.Herein,an iron(Fe)-doped WO_(3−x) gas sensor was employed for greatly sensitive,selective,and scalable geranyl acetone detection.The results proved that precisely-regulated oxygen vacancy(OV)and sophisticatedly-active electron transition of Fe-doped WO_(3−x) nanoparticles were fulfilled by modifying the doping amount of Fe^(3+),leading to the prominently enhanced sensitivity(23.47 at 6 ppm),low limit of detection(LOD)(237 ppb),optimal selectivity,and outstanding long-term stability.Furthermore,the enhancing mechanism of gas sensing performance was substantiated through density functional theory(DFT)calculation,while the practical application for the evaluation of spoiled cooked rice was conducted as well.This study demonstrates a reliable method for detecting a VOC biomarker in cooked rice,which can ensure food security and improve palatability of cooked rice.展开更多
基金funded by Youth Program of National Natural Science Foundation of China(52002034)National Key R&D Program of China(2018YFB1600701)+2 种基金Key Research and Development Program of Shaanxi(2020ZDLGY16-01,2019ZDLGY15-02)Natural Science Basic Research Program of Shaanxi(2020JQ-381)Fundamental Research Funds for the Central Universities,CHD(300102220113).
文摘Combined with the characteristics of the distributed-drive electric vehicle and direct yaw moment control,a double-layer structure direct yaw moment controller is designed.The upper additional yaw moment controller is constructed based on model predictive control.Aiming at minimizing the utilization rate of tire adhesion and constrained by the working characteristics of motor system and brake system,a quadratic programming active set was designed to optimize the distribution of additional yaw moments.The road surface adhesion coefficient has a great impact on the reliability of direct yaw moment control,for which joint observer of vehicle state parameters and road surface parameters is designed by using unscented Kalman filter algorithm,which correlates vehicle state observer and road surface parameter observer to form closed-loop feedback correction.The results show that compared to the“feedforward+feedback”control,the vehicle’s error of yaw rate and sideslip angle by the model predictive control is smaller,which can improve the vehicle stability effectively.In addition,according to the results of the docking road simulation test,the joint observer of vehicle state and road surface parameters can improve the adaptability of the vehicle stability controller to the road conditions with variable adhesion coefficients.
基金supported by the Outstanding Youth Foundation of Jiangsu Province of China(No.BK20211548)the Qinglan Project of Yangzhou University,and the Yangzhou Science and Technology Plan Project(No.YZ2023246).
文摘Because the volatile content of isoamyl alcohol increases sharply on the seventh day of wheat mildew infection,isoamyl alcohol can be used as an early biomarker of wheat mildew infection.Currently,only a few sensors for isoamyl alcohol detection have been reported,and these sensors still suffer from low sensitivity and poor moisture resistance.Herein,the isoamyl alcohol sensitivity of 5 at%Er@LaFeO_(3)(ELFO)was enhanced by loading Ag nanoparticles on the surface of the ELFO microspheres,while the optimal operating temperature was reduced.The moisture resistance of Ag/ELFO was improved by the incorporation of g-C_(3)N_(4)nanosheets(NSs)on the surface of Ag/ELFO through electrostatic self-assembly.Given the requirements for practical applications in grain granaries,the sensing behavior of a Ag/ELFO-based sensor incorporating g-C_(3)N_(4)NSs at 20%relative humidity(RH)was systematically studied,and the sensor demonstrated excellent repeatability,long-term stability,and superior selectivity(791 at 50 ppm)for isoamyl alcohol with a low limit of detection(LOD=75 ppb).Furthermore,the practical results obtained for wheat at different mildew stages further confirmed the potential of the g-C_(3)N_(4)/Ag/ELFO-based sensor for monitoring the early mildew stage of wheat.This work may offer guidance for enhancing the moisture resistance of gas-sensitive materials through the strategy of employing composite nanomaterials.
基金the Outstanding Youth Foundation of Jiangsu Province of China(No.BK20211548)the Yangzhou Science and Technology Plan Project(No.YZ2023246)the Qinglan Project of Yangzhou University,and the Research Innovation Plan of Graduate Education Innovation Project in Jiangsu Province(No.KYCX23_3530).
文摘In the early-stage diagnosis of lung cancer,the low-concentration(<5 ppm)volatile organic compounds(VOCs)are extensively identified to be the biomarkers for breath analysis.Herein,the urchin-like sodium(Na)-doped zinc oxide(ZnO)nanoneedles were synthesized through a hydrothermal strategy with the addition of different contents of citric acid.The Na-doped ZnO gas sensor with a 3:1 molar ratio of Na^(+)and citric acid showed outstanding sensing properties with an optimal selectivity to various VOCs(formaldehyde(HCOH),isopropanol,acetone,and ammonia)based on working temperature regulation.Specifically,significantly enhanced sensitivity(21.3@5 ppm)compared with pristine ZnO(~7-fold),low limit of detection(LOD)(298 ppb),robust humidity resistance,and long-term stability of formaldehyde sensing performances were obtained,which can be attributed to the formation of a higher concentration of oxygen vacancies(20.98%)and the active electron transitions.Furthermore,the improved sensing mechanism was demonstrated by the exquisite band structure and introduction of the additional acceptor level,which resulted in the narrowed bandgap of ZnO.
基金This work was supported by the Outstanding Youth Foundation of Jiangsu Province of China(No.BK20211548)the National Natural Science Foundation of China(No.51872254)the Yangzhou City-Yangzhou University Cooperation Foundation(No.YZ2021153).
文摘In the assessment of food quality,geranyl acetone plays a crucial role as a volatile organic compound(VOC)biomarker for diverse agricultural products,while the ultralow concentration detection meeting application requirements has been barely studied.Herein,an iron(Fe)-doped WO_(3−x) gas sensor was employed for greatly sensitive,selective,and scalable geranyl acetone detection.The results proved that precisely-regulated oxygen vacancy(OV)and sophisticatedly-active electron transition of Fe-doped WO_(3−x) nanoparticles were fulfilled by modifying the doping amount of Fe^(3+),leading to the prominently enhanced sensitivity(23.47 at 6 ppm),low limit of detection(LOD)(237 ppb),optimal selectivity,and outstanding long-term stability.Furthermore,the enhancing mechanism of gas sensing performance was substantiated through density functional theory(DFT)calculation,while the practical application for the evaluation of spoiled cooked rice was conducted as well.This study demonstrates a reliable method for detecting a VOC biomarker in cooked rice,which can ensure food security and improve palatability of cooked rice.