All solid-state electrolytes have the advantages of good mechanical and thermal properties for safer energy storage,but their energy density has been limited by low ionic conductivity and large interfacial resistance ...All solid-state electrolytes have the advantages of good mechanical and thermal properties for safer energy storage,but their energy density has been limited by low ionic conductivity and large interfacial resistance caused by the poor Li~+transport kinetics due to the solid-solid contacts between the electrodes and the solid-state electrolytes.Herein,a novel gel polymer electrolyte(UPP-5)composed of ionic liquid incorporated metal-organic frameworks nanoparticles(IL@MOFs)is designed,it exhibits satisfying electrochemical performances,consisting of an excellent electrochemical stability window(5.5 V)and an improved Li^(+)transference number of 0.52.Moreover,the Li/UPP-5/LiFePO_(4) full cells present an ultra-stable cycling performance at 0.2C for over 100 cycles almost without any decay in capacities.This study might provide new insight to create an effective Li^(+)conductive network for the development of all-solid-state lithium-ion batteries.展开更多
The COVID-19 pandemic forced many universities around the world to move their educational activities onto online platforms.We conducted a survey in which asking undergraduates at a Chinese university how they felt abo...The COVID-19 pandemic forced many universities around the world to move their educational activities onto online platforms.We conducted a survey in which asking undergraduates at a Chinese university how they felt about different aspects of online education during the pandemic.We received responses from 1,088 students.A majority of the students(67.9%)thought that physical classroom is better than online education and MOOCs.The students believed that teachers have improved their ability to teach online since the pandemic(67.3%)and online teaching is a suitable option in the current situation(65.8%).The students expressed satisfaction with the online educational resources and teachers’flexible use of online tools.However,the students felt that online education is stressful and affecting their health and social life.The pandemic has led to widespread use of online education,and we hope that online education can be better in the future.展开更多
In the industrial production of expanded thermoplastic polyurethane (E-TPU) midsoles, the surface defects still rely on manual inspection at present, and the eligibility criteria are uneven. Therefore, this paper prop...In the industrial production of expanded thermoplastic polyurethane (E-TPU) midsoles, the surface defects still rely on manual inspection at present, and the eligibility criteria are uneven. Therefore, this paper proposes an E-TPU midsole surface defect detection method based on machine vision to achieve automatic detection and defect classification. The proposed method is divided into three parts: image preprocessing, block defect detection, and linear defect detection. Image preprocessing uses RGB three channel self-inspection to identify scorch and color pollution. Block defect detection uses superpixel segmentation and background prior mining to determine holes, impurities, and dirt. Linear defect detection uses Gabor filter and Hough transform to detect indentation and convex marks. After image preprocessing, block defect detection and linear defect detection are simultaneously performed by parallel computing. The false positive rate (FPR) of the proposed method in this paper is 8.3%, the false negatives rate (FNR) of the hole is 4.7%, the FNR of indentation is 2.1%, and the running time does not exceed 1.6 s. The test results show that this method can quickly and accurately detect various defects in the E-TPU midsole.展开更多
基金financially supported by National Natural Science Foundation of China (No.21701083)。
文摘All solid-state electrolytes have the advantages of good mechanical and thermal properties for safer energy storage,but their energy density has been limited by low ionic conductivity and large interfacial resistance caused by the poor Li~+transport kinetics due to the solid-solid contacts between the electrodes and the solid-state electrolytes.Herein,a novel gel polymer electrolyte(UPP-5)composed of ionic liquid incorporated metal-organic frameworks nanoparticles(IL@MOFs)is designed,it exhibits satisfying electrochemical performances,consisting of an excellent electrochemical stability window(5.5 V)and an improved Li^(+)transference number of 0.52.Moreover,the Li/UPP-5/LiFePO_(4) full cells present an ultra-stable cycling performance at 0.2C for over 100 cycles almost without any decay in capacities.This study might provide new insight to create an effective Li^(+)conductive network for the development of all-solid-state lithium-ion batteries.
文摘The COVID-19 pandemic forced many universities around the world to move their educational activities onto online platforms.We conducted a survey in which asking undergraduates at a Chinese university how they felt about different aspects of online education during the pandemic.We received responses from 1,088 students.A majority of the students(67.9%)thought that physical classroom is better than online education and MOOCs.The students believed that teachers have improved their ability to teach online since the pandemic(67.3%)and online teaching is a suitable option in the current situation(65.8%).The students expressed satisfaction with the online educational resources and teachers’flexible use of online tools.However,the students felt that online education is stressful and affecting their health and social life.The pandemic has led to widespread use of online education,and we hope that online education can be better in the future.
文摘In the industrial production of expanded thermoplastic polyurethane (E-TPU) midsoles, the surface defects still rely on manual inspection at present, and the eligibility criteria are uneven. Therefore, this paper proposes an E-TPU midsole surface defect detection method based on machine vision to achieve automatic detection and defect classification. The proposed method is divided into three parts: image preprocessing, block defect detection, and linear defect detection. Image preprocessing uses RGB three channel self-inspection to identify scorch and color pollution. Block defect detection uses superpixel segmentation and background prior mining to determine holes, impurities, and dirt. Linear defect detection uses Gabor filter and Hough transform to detect indentation and convex marks. After image preprocessing, block defect detection and linear defect detection are simultaneously performed by parallel computing. The false positive rate (FPR) of the proposed method in this paper is 8.3%, the false negatives rate (FNR) of the hole is 4.7%, the FNR of indentation is 2.1%, and the running time does not exceed 1.6 s. The test results show that this method can quickly and accurately detect various defects in the E-TPU midsole.