Aqueous organic redox flow batteries(AORFBs)exploit the reversible electrochemical reactions of watersoluble organic redox-active species to store electricity and have emerged as promising electrochemical energy stora...Aqueous organic redox flow batteries(AORFBs)exploit the reversible electrochemical reactions of watersoluble organic redox-active species to store electricity and have emerged as promising electrochemical energy storage technologies.To improve the battery performance related to the cell resistance,such as the power density and energy efficiency,it is essential to understand the cell resistance and determine the major contributor.Here,we conduct comprehensive electrochemical impedance spectroscopy(EIS)studies and cell polarization on a representative TEMPTMA/MV cell assembled with a commercial AMVN membrane and probe the proportion of the ohmic resistance to the total cell resistance at various stages of charge(SOCs)ranging from 10%to 100%.At 0 mA·cm^(−2),the ohmic resistance is responsible for 60.3%–71.7%of the resistance of the entire cell,whereas at high current densities(for example,when the power density reaches the maximum),the ohmic resistance still contributes 47.9%–61.4%.Our quantitative analysis highlights the dominance of the ohmic resistance and anticipates that a membrane with lower resistivity may significantly increase the power density.展开更多
Aqueous organic redox flow batteries(AORFBs),which exploit the reversible electrochemical reactions of water-soluble organic electrolytes to store electricity,have emerged as an efficient electrochemical energy storag...Aqueous organic redox flow batteries(AORFBs),which exploit the reversible electrochemical reactions of water-soluble organic electrolytes to store electricity,have emerged as an efficient electrochemical energy storage technology for the grid-scale integration of renewable electricity.pH-neutral AORFBs that feature high safety,low corrosivity,and environmental benignity are particularly promising,and their battery performance is significantly impacted by redox-active molecules and ion-exchange membranes(IEMs).Here,representative anolytes and catholytes engineered for use in pH-neutral AORFBs are outlined and summarized,as well as their side reactions that cause irreversible battery capacity fading.In addition,the recent achievements of IEMs for pH-neutral AORFBs are discussed,with a focus on the construction and tuning of ion transport channels.Finally,the critical challenges and potential research opportunities for developing practically relevant pH-neutral AORFBs are presented.展开更多
Background:To understand the relationship between myocardial contractility and ex-ternal stimuli,detecting ex vivo myocardial contractility is necessary.Methods:We elaborated a method for contractility detection of is...Background:To understand the relationship between myocardial contractility and ex-ternal stimuli,detecting ex vivo myocardial contractility is necessary.Methods:We elaborated a method for contractility detection of isolated C57 mouse papillary muscle using Myostation-Intact system under different frequencies,volt-ages,and calcium concentrations.Results:The results indicated that the basal contractility of the papillary muscle was 0.27±0.03 mN at 10 V,500-ms pulse duration,and 1 Hz.From 0.1 to 1.0 Hz,con-tractility decreased with an increase in frequency(0.45±0.11-0.10±0.02 mN).The voltage-initiated muscle contractility varied from 3 to 6 V,and the contractility gradu-ally increased as the voltage increased from 6 to 10 V(0.14±0.02-0.28±0.03 mN).Moreover,the muscle contractility increased when the calcium concentration was increased from 1.5 to 3 mM(0.45±0.17-1.11±0.05 mN);however,the contractility stopped increasing even when the concentration was increased to 7.5 mM(1.02±0.23 mN).Conclusions:Our method guaranteed the survivability of papillary muscle ex vivo and provided instructions for Myostation-Intact users for isolated muscle contractility investigations.展开更多
Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, imp...Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, improved safety and low cost. The development of high-voltage AFB is, however, limited by the lack of stable anolytes that have low redox potential. Here we report Eu-based anolytes for high-voltage p H-neutral AFB applications. Eu^(3+) has a reduction potential of -0.39 V vs. SHE, which can be dramatically lowered when forming stable complex with inexpensive organic chelates. A typical complex, Eu DTPA,features a low redox potential of -1.09 V vs. SHE, fast redox kinetics, and a high water solubility of 1.5 M. When paired with ferrocyanide, the battery had an open-circuit voltage of 1.56 V and demonstrated stable cell cycling performance, including a capacity retention rate of 99.997% per cycle over500 cycles at 40 m A cm^(-2), a current efficiency of >99.9%, and an energy efficiency of >83.3%. A high concentration anolyte at 1.5 M exhibited a volumetric capacity of 40.2 Ah L^(-1), which is one of the highest known for p H-neutral AFBs, promising a potent solution for the grid-scale storage of renewable electricity.展开更多
The understanding of anion transporting behaviors under sub-nanoconfined regimes can guide the design of high-performance anion selective membranes(ASMs),yet it is little known.Here,we build membrane channels that com...The understanding of anion transporting behaviors under sub-nanoconfined regimes can guide the design of high-performance anion selective membranes(ASMs),yet it is little known.Here,we build membrane channels that combine physical rigidity with chemical affinity to anions simply through bridging graphene oxide nanosheets with charged linkers.We observe that the rigidly confined interaction imposed by channels to anions can reconfigure hydration shells in varying degrees for different anions via compensating for hydration-induced energy barriers and differentiating their rearrangement behaviors.During the configuration evolution,water molecules within hydration shells would rotate and simultaneously change their distance from the ion center.Based on the big discrepancy in configuration evolution,these membranes can realize ultrahigh selectivity of,for example,125 for Cl^(-)/SO_(4)^(2-)and surpass the performance upper bound concerning Cl^(-)/SO_(4)^(2-)separation by other membranes.The knowledge of the configuration change of hydration shells during the dehydration process will be key to designing next-generation ASMs.展开更多
Introduction:On September 11,2024,a foodborne disease outbreak occurred at a middle school.Upon receiving the report,investigators promptly arrived at the scene to verify the incident,identify suspicious food items an...Introduction:On September 11,2024,a foodborne disease outbreak occurred at a middle school.Upon receiving the report,investigators promptly arrived at the scene to verify the incident,identify suspicious food items and risk factors that contributed to the outbreak,providing a reference for the prevention and investigation of similar incidents in the future.Methods:Epidemiological methods were employed to characterize the clinical and epidemiological features of cases.A case-control study was conducted to identify suspicious meals and food items.Samples from cases,food products,and environmental sources were collected for laboratory testing.Results:A total of 112 cases met the case definition,with an attack rate of 3.20%.The predominant clinical manifestations included fever(100.00%),diarrhea(92.86%),and vomiting(34.82%).The case-control study indicated that egg cakes and soybean milk sold at window 17 of the Second canteen were the suspicious food items.By September 12,252 samples had been collected,with laboratory testing detecting Salmonella Newport in 26 samples.Conclusion:Based on epidemiological investigation,hygienic assessment,and laboratory testing results,this incident is classified as an outbreak of foodborne disease caused by Salmonella Newport contamination.The health and well-being of students is paramount,necessitating strengthened food hygiene supervision in schools,regular food safety knowledge training,and comprehensive measures to reduce the risk of foodborne disease in educational settings.展开更多
Ion exchange membranes(IEMs) play a significant role in fields of energy and environment, for instance fuel cells, diffusion dialysis, electrodialysis, etc. The limited choice of commercially available IEMs has produc...Ion exchange membranes(IEMs) play a significant role in fields of energy and environment, for instance fuel cells, diffusion dialysis, electrodialysis, etc. The limited choice of commercially available IEMs has produced a strong demand of fabricating IEMs with improved properties via facile synthetic strategies over the past two decades. Poly(phenylene oxide)(PPO) is considered as a promising polymeric material for constructing practical IEMs, due to its advantages of good physicochemical properties, low manufacturing cost and easy post functionalization. In this review, we present the accumulated efforts in synthetic strategies towards diverse types of PPO-based IEMs. Relation between polymer structures and the resulted features is discussed in detail. Besides, applying IEMs from PPO and its derivatives in fuel cell, diffusion dialysis and electrodialysis is summarized and commented.展开更多
In this paper,we employ qualitative analysis and methods of bifurcation theory to study the maximum number of limit cycles for a polynomial system with center in global bifurcation.
基金supported by the National Natural Science Foundation of China(22308345)the Anhui Provincial Natural Science Foundation(2308085QB68)the Fundamental Research Funds for the Central Universities(WK2060000059).
文摘Aqueous organic redox flow batteries(AORFBs)exploit the reversible electrochemical reactions of watersoluble organic redox-active species to store electricity and have emerged as promising electrochemical energy storage technologies.To improve the battery performance related to the cell resistance,such as the power density and energy efficiency,it is essential to understand the cell resistance and determine the major contributor.Here,we conduct comprehensive electrochemical impedance spectroscopy(EIS)studies and cell polarization on a representative TEMPTMA/MV cell assembled with a commercial AMVN membrane and probe the proportion of the ohmic resistance to the total cell resistance at various stages of charge(SOCs)ranging from 10%to 100%.At 0 mA·cm^(−2),the ohmic resistance is responsible for 60.3%–71.7%of the resistance of the entire cell,whereas at high current densities(for example,when the power density reaches the maximum),the ohmic resistance still contributes 47.9%–61.4%.Our quantitative analysis highlights the dominance of the ohmic resistance and anticipates that a membrane with lower resistivity may significantly increase the power density.
基金funded by the National Key Research and Development Program of China(Nos.2022YFB3805303,2022YFB3805304)the National Natural Science Foundation of China(Grant/Award Numbers:22308345,U20A20127)+1 种基金the Anhui Provincial Natural Science Foundation(No.2308085QB68)the Fundamental Research Funds for the Central Universities(No.WK2060000059).
文摘Aqueous organic redox flow batteries(AORFBs),which exploit the reversible electrochemical reactions of water-soluble organic electrolytes to store electricity,have emerged as an efficient electrochemical energy storage technology for the grid-scale integration of renewable electricity.pH-neutral AORFBs that feature high safety,low corrosivity,and environmental benignity are particularly promising,and their battery performance is significantly impacted by redox-active molecules and ion-exchange membranes(IEMs).Here,representative anolytes and catholytes engineered for use in pH-neutral AORFBs are outlined and summarized,as well as their side reactions that cause irreversible battery capacity fading.In addition,the recent achievements of IEMs for pH-neutral AORFBs are discussed,with a focus on the construction and tuning of ion transport channels.Finally,the critical challenges and potential research opportunities for developing practically relevant pH-neutral AORFBs are presented.
基金Specialized Project of Fuwai Hospital,Grant/Award Number:2022-FWTS07Shenzhen Sanming Project of Medicine,Grant/Award Number:2016-SZZF02+1 种基金National Natural Science Foundation of China,Grant/Award Number:81900343CAMS Innovation Fund for Medical Sciences,Grant/Award Number:CIFMS,2021-I2M-C&T-A-011。
文摘Background:To understand the relationship between myocardial contractility and ex-ternal stimuli,detecting ex vivo myocardial contractility is necessary.Methods:We elaborated a method for contractility detection of isolated C57 mouse papillary muscle using Myostation-Intact system under different frequencies,volt-ages,and calcium concentrations.Results:The results indicated that the basal contractility of the papillary muscle was 0.27±0.03 mN at 10 V,500-ms pulse duration,and 1 Hz.From 0.1 to 1.0 Hz,con-tractility decreased with an increase in frequency(0.45±0.11-0.10±0.02 mN).The voltage-initiated muscle contractility varied from 3 to 6 V,and the contractility gradu-ally increased as the voltage increased from 6 to 10 V(0.14±0.02-0.28±0.03 mN).Moreover,the muscle contractility increased when the calcium concentration was increased from 1.5 to 3 mM(0.45±0.17-1.11±0.05 mN);however,the contractility stopped increasing even when the concentration was increased to 7.5 mM(1.02±0.23 mN).Conclusions:Our method guaranteed the survivability of papillary muscle ex vivo and provided instructions for Myostation-Intact users for isolated muscle contractility investigations.
基金project has been supported by the National Natural Science Foundation of China (Nos. 21878281, 21922510 and 21720102003)the DNL Cooperation Fund, CAS (DNL201910)。
文摘Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, improved safety and low cost. The development of high-voltage AFB is, however, limited by the lack of stable anolytes that have low redox potential. Here we report Eu-based anolytes for high-voltage p H-neutral AFB applications. Eu^(3+) has a reduction potential of -0.39 V vs. SHE, which can be dramatically lowered when forming stable complex with inexpensive organic chelates. A typical complex, Eu DTPA,features a low redox potential of -1.09 V vs. SHE, fast redox kinetics, and a high water solubility of 1.5 M. When paired with ferrocyanide, the battery had an open-circuit voltage of 1.56 V and demonstrated stable cell cycling performance, including a capacity retention rate of 99.997% per cycle over500 cycles at 40 m A cm^(-2), a current efficiency of >99.9%, and an energy efficiency of >83.3%. A high concentration anolyte at 1.5 M exhibited a volumetric capacity of 40.2 Ah L^(-1), which is one of the highest known for p H-neutral AFBs, promising a potent solution for the grid-scale storage of renewable electricity.
基金supported by the National Key R&D Program of China (2022YFB3805102)the National Natural Science Foundation of China (22278105, 21978062)。
文摘The understanding of anion transporting behaviors under sub-nanoconfined regimes can guide the design of high-performance anion selective membranes(ASMs),yet it is little known.Here,we build membrane channels that combine physical rigidity with chemical affinity to anions simply through bridging graphene oxide nanosheets with charged linkers.We observe that the rigidly confined interaction imposed by channels to anions can reconfigure hydration shells in varying degrees for different anions via compensating for hydration-induced energy barriers and differentiating their rearrangement behaviors.During the configuration evolution,water molecules within hydration shells would rotate and simultaneously change their distance from the ion center.Based on the big discrepancy in configuration evolution,these membranes can realize ultrahigh selectivity of,for example,125 for Cl^(-)/SO_(4)^(2-)and surpass the performance upper bound concerning Cl^(-)/SO_(4)^(2-)separation by other membranes.The knowledge of the configuration change of hydration shells during the dehydration process will be key to designing next-generation ASMs.
基金Granted by Ethics Committee of Guizhou Provincial Center for Disease Control and Prevention(Q2024-07).
文摘Introduction:On September 11,2024,a foodborne disease outbreak occurred at a middle school.Upon receiving the report,investigators promptly arrived at the scene to verify the incident,identify suspicious food items and risk factors that contributed to the outbreak,providing a reference for the prevention and investigation of similar incidents in the future.Methods:Epidemiological methods were employed to characterize the clinical and epidemiological features of cases.A case-control study was conducted to identify suspicious meals and food items.Samples from cases,food products,and environmental sources were collected for laboratory testing.Results:A total of 112 cases met the case definition,with an attack rate of 3.20%.The predominant clinical manifestations included fever(100.00%),diarrhea(92.86%),and vomiting(34.82%).The case-control study indicated that egg cakes and soybean milk sold at window 17 of the Second canteen were the suspicious food items.By September 12,252 samples had been collected,with laboratory testing detecting Salmonella Newport in 26 samples.Conclusion:Based on epidemiological investigation,hygienic assessment,and laboratory testing results,this incident is classified as an outbreak of foodborne disease caused by Salmonella Newport contamination.The health and well-being of students is paramount,necessitating strengthened food hygiene supervision in schools,regular food safety knowledge training,and comprehensive measures to reduce the risk of foodborne disease in educational settings.
基金supported by the National Natural Science Foundation of China (21506201, 21720102003, 91534203)the Key Technologies R&D Program of Anhui Province (17030901079)+1 种基金K. C. Wong Education Foundation (2016-11)International Partnership Program of Chinese Academy of Sciences (21134ky5b20170010)
文摘Ion exchange membranes(IEMs) play a significant role in fields of energy and environment, for instance fuel cells, diffusion dialysis, electrodialysis, etc. The limited choice of commercially available IEMs has produced a strong demand of fabricating IEMs with improved properties via facile synthetic strategies over the past two decades. Poly(phenylene oxide)(PPO) is considered as a promising polymeric material for constructing practical IEMs, due to its advantages of good physicochemical properties, low manufacturing cost and easy post functionalization. In this review, we present the accumulated efforts in synthetic strategies towards diverse types of PPO-based IEMs. Relation between polymer structures and the resulted features is discussed in detail. Besides, applying IEMs from PPO and its derivatives in fuel cell, diffusion dialysis and electrodialysis is summarized and commented.
基金supported by Foundation of Shanghai Municipal Education Committee(10YZ72)
文摘In this paper,we employ qualitative analysis and methods of bifurcation theory to study the maximum number of limit cycles for a polynomial system with center in global bifurcation.
