Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements ...Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.展开更多
The production of face towels is growing at an annual rate of about 4%in China,reaching 1.13 million tons by 2021.Phthalates(PAEs)are widely used in textiles,and face towels,as an important household textile,may expos...The production of face towels is growing at an annual rate of about 4%in China,reaching 1.13 million tons by 2021.Phthalates(PAEs)are widely used in textiles,and face towels,as an important household textile,may expose people to PAEs via the skin,further leading to health risks.We collected new face towels and analyzed the distribution characterization of PAEs in them.The changes of PAEs were explored in a face towel use experiment and a simulated laundry experiment.Based on the use of face towels by 24 volunteers,we calculated the estimated daily intake(EDI)and comprehensively assessed the hazard quotient(HQ),hazard index(HI),and dermal cancer risk(DCR)of PAEs exposure in the population.PAEs were present in new face towels at total concentrations of<MDL–2388 ng/g,with a median of 173.2 ng/g,which was a lower contamination level compared with other textiles.PAE contents in used face towels were significantly higher than in new face towels.The concentrations of PAEs in coral velvet were significantly higher than those in cotton.Water washing removed some PAEs,while detergent washing increased the PAE content on face towels.Gender,weight,use time,and material were the main factors affecting EDI.The HQ and HIwere less than 1,which proved PAEs had no significant non-carcinogenic health risks.Among the five target PAEs studied,DEHPwas the only carcinogenic PAE andmay cause potential health risks after long-term exposure.Therefore,we should pay more attention to DEHP.展开更多
To study the effects of combined Cd and Cu pollution on rhizosphere bacterial community.High-throughput sequencing was used to examine the response of rhizosphere bacterial communities to heavy-metal stress under sing...To study the effects of combined Cd and Cu pollution on rhizosphere bacterial community.High-throughput sequencing was used to examine the response of rhizosphere bacterial communities to heavy-metal stress under single and mixed pollution of cadmium(Cd)and copper(Cu).With additions of Cd and Cu,the mean diversity index of rhizosphere bacterial community was in the order Cu alone>Cd-Cu mixtures>Cd alone.In all Cd and Cu treatments,the dominant phyla were Proteobacteria,Actinobacteria,Chloroflexi and Acidobacteria.In the additions with different concentrations of Cd-Cu mixtures,LEfSe indicated that there were differences in the predominant species of rhizosphere bacterial communities.Some genera such as Streptomyces and Microbacterium belonging to Actinobacteria as biomarkers were significantly enriched in both control and treatments,while some genera such as Pseudoxanthomonas and Rhodopseudomonas belonging to Proteobacteria as biomarkers were observed to be enriched in the additions with single and mixture of Cd and Cu.According to the Nonmetric multidimensional scaling(NMDS)analysis,the structure of rhizosphere bacterial community was different between treatments and the CK.Principal Component Analysis(PCA)and permutational multivariate analysis of variance(PERMANOVA)showed that there were significant differences among treatments(p<0.01),and that the addition of Cu might be the primary factor affecting the composition of rhizosphere bacterial communities.展开更多
Supramolecular polymers, which combined of the supramolecular chemistry and polymer science, are constructed from monomers together by reversible noncovalent interactions. Supramolecular polymers in aqueous solution a...Supramolecular polymers, which combined of the supramolecular chemistry and polymer science, are constructed from monomers together by reversible noncovalent interactions. Supramolecular polymers in aqueous solution are especially important due to their superior biocompatibility and environmental adaptation, which determined they have wide applications in various areas, such as drug delivery, selfhealing, shape memory. Macrocyclic compounds, such as cyclodextrins, calixarenes, cucurbiturils and pillar[n]arenes, are the most used building blocks in the preparation of supramolecular polymers.Macrocycle-based supramolecular polymers, which introduce the host-guest interaction in the system,endow these polymers with interesting and smart physical-chemical properties. In this review, we summarized recent studies about supramolecular polymers in aqueous solution based on macrocyclic compounds.展开更多
Synchrotron X-ray radiography was used to carry out an in-situ observation of the hydrogen bubble evolution in the liquid Al/solid Ni interconnection. The individual bubble mainly grows in a stochastic way during heat...Synchrotron X-ray radiography was used to carry out an in-situ observation of the hydrogen bubble evolution in the liquid Al/solid Ni interconnection. The individual bubble mainly grows in a stochastic way during heating. The size distribution for groups of bubbles follows a Gaussian distribution in the early stage and Lifshitz-Slyozov-Wagner(LSW) diffusion controlled distribution in the final stage. The intermetallic compounds(IMCs) first form during solidification, following by the hydrogen bubbles. The bubbles between two adjacent Al3Ni grains grow unidirectionally along the liquid channel, with the bottom being impeded by the Al3Ni phase and the radius of the growth front being smaller. For the bubbles at triple junctions, they grow along the liquid channel and the crack with morphology transition.展开更多
Past studies on the Chinese internet management system have revealed a smart internet management system that takes advantage of time to filter content with collective action potential.How and why such a system was ins...Past studies on the Chinese internet management system have revealed a smart internet management system that takes advantage of time to filter content with collective action potential.How and why such a system was institutionalized?We offer a historical institutional analysis to explain the way in which the system evolved.We implement social network analysis to examine the Weibo posts of recurrent events,the elections in Area A in 2016 and 2018,to identify pattern changes in the system.There are two aspects of the changes:the centralization of the command line to a single authority and the implementation of a discriminatory strategy to deal with the various online expressions together forming this intelligent system.The improved Chinese information surveillance system demonstrates both a top-down information management and a bottom-up opinion formation.展开更多
The influence of Cu content on the reaction process, reaction behavior and obtained products in the Cu-ZrC system, as well as their relationships, were investigated. The results showed that Zr C was synthesized throug...The influence of Cu content on the reaction process, reaction behavior and obtained products in the Cu-ZrC system, as well as their relationships, were investigated. The results showed that Zr C was synthesized through the diffusion and dissolution of C into a Cu-Zr liquid. Increasing the Cu content enhanced the amount of Cu-Zr liquid formed at the early stage but decreased the amount of C atoms dissolving into the melt at unit time. Consequently, the ignition time initially decreased and then increased. Conversely, with an increased Cu content, the energy required for igniting the neighboring unreacted powders increased,while the heat released by the reaction and the dwell time of the compact at high temperatures decreased.These effects then resulted in the reduction of combustion wave velocity, combustion temperature and Zr C particle size. Furthermore, the synthesis of ZrC is a multistage process, which provides a nonuniform distributed Zr C particle size. The sub-μm Zr C particle reinforced Cu matrix composite was fabricated by adding a ZrC-Cu master alloy prepared through a self-propagating high-temperature synthesis reaction into liquid Cu.展开更多
基金The work described in this paper was fully supported by a Grant from the City University of Hong Kong(Project No.9610641).
文摘Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.
基金supported by the National Natural Science Foundation of China(No.42177413)the Natural Science Foundation of Jilin Province(No.20210203008SF)the Leading Talents and Team Project of Scientific and Technological Innovation for Young and Middle-aged Group in Jilin Province(No.20200301015RQ).
文摘The production of face towels is growing at an annual rate of about 4%in China,reaching 1.13 million tons by 2021.Phthalates(PAEs)are widely used in textiles,and face towels,as an important household textile,may expose people to PAEs via the skin,further leading to health risks.We collected new face towels and analyzed the distribution characterization of PAEs in them.The changes of PAEs were explored in a face towel use experiment and a simulated laundry experiment.Based on the use of face towels by 24 volunteers,we calculated the estimated daily intake(EDI)and comprehensively assessed the hazard quotient(HQ),hazard index(HI),and dermal cancer risk(DCR)of PAEs exposure in the population.PAEs were present in new face towels at total concentrations of<MDL–2388 ng/g,with a median of 173.2 ng/g,which was a lower contamination level compared with other textiles.PAE contents in used face towels were significantly higher than in new face towels.The concentrations of PAEs in coral velvet were significantly higher than those in cotton.Water washing removed some PAEs,while detergent washing increased the PAE content on face towels.Gender,weight,use time,and material were the main factors affecting EDI.The HQ and HIwere less than 1,which proved PAEs had no significant non-carcinogenic health risks.Among the five target PAEs studied,DEHPwas the only carcinogenic PAE andmay cause potential health risks after long-term exposure.Therefore,we should pay more attention to DEHP.
文摘To study the effects of combined Cd and Cu pollution on rhizosphere bacterial community.High-throughput sequencing was used to examine the response of rhizosphere bacterial communities to heavy-metal stress under single and mixed pollution of cadmium(Cd)and copper(Cu).With additions of Cd and Cu,the mean diversity index of rhizosphere bacterial community was in the order Cu alone>Cd-Cu mixtures>Cd alone.In all Cd and Cu treatments,the dominant phyla were Proteobacteria,Actinobacteria,Chloroflexi and Acidobacteria.In the additions with different concentrations of Cd-Cu mixtures,LEfSe indicated that there were differences in the predominant species of rhizosphere bacterial communities.Some genera such as Streptomyces and Microbacterium belonging to Actinobacteria as biomarkers were significantly enriched in both control and treatments,while some genera such as Pseudoxanthomonas and Rhodopseudomonas belonging to Proteobacteria as biomarkers were observed to be enriched in the additions with single and mixture of Cd and Cu.According to the Nonmetric multidimensional scaling(NMDS)analysis,the structure of rhizosphere bacterial community was different between treatments and the CK.Principal Component Analysis(PCA)and permutational multivariate analysis of variance(PERMANOVA)showed that there were significant differences among treatments(p<0.01),and that the addition of Cu might be the primary factor affecting the composition of rhizosphere bacterial communities.
基金supported the National Natural Science Foundation of China (No. 21801139)Natural Science Foundation of Jiangsu Province (No. BK20180942)+1 种基金the Natural Science Foundation of Nantong University (No. 03083004)the large instruments open foundation of Nantong university (1No. KFJN1814)
文摘Supramolecular polymers, which combined of the supramolecular chemistry and polymer science, are constructed from monomers together by reversible noncovalent interactions. Supramolecular polymers in aqueous solution are especially important due to their superior biocompatibility and environmental adaptation, which determined they have wide applications in various areas, such as drug delivery, selfhealing, shape memory. Macrocyclic compounds, such as cyclodextrins, calixarenes, cucurbiturils and pillar[n]arenes, are the most used building blocks in the preparation of supramolecular polymers.Macrocycle-based supramolecular polymers, which introduce the host-guest interaction in the system,endow these polymers with interesting and smart physical-chemical properties. In this review, we summarized recent studies about supramolecular polymers in aqueous solution based on macrocyclic compounds.
基金supported by the National Key Research and Development Program (2017YFA0403800)the National Natural Science Foundation of China (51374144, 51727802)+2 种基金the Shanghai Municipal Natural Science Foundation (13ZR1420600)Shanghai Rising-Star Program (14QA1402300)The support of synchrotron radiation phase-contrast imaging by the BL13W1 beam line of Shanghai Synchrotron Radiation Facility (SSRF), China, is gratefully acknowledged
文摘Synchrotron X-ray radiography was used to carry out an in-situ observation of the hydrogen bubble evolution in the liquid Al/solid Ni interconnection. The individual bubble mainly grows in a stochastic way during heating. The size distribution for groups of bubbles follows a Gaussian distribution in the early stage and Lifshitz-Slyozov-Wagner(LSW) diffusion controlled distribution in the final stage. The intermetallic compounds(IMCs) first form during solidification, following by the hydrogen bubbles. The bubbles between two adjacent Al3Ni grains grow unidirectionally along the liquid channel, with the bottom being impeded by the Al3Ni phase and the radius of the growth front being smaller. For the bubbles at triple junctions, they grow along the liquid channel and the crack with morphology transition.
文摘Past studies on the Chinese internet management system have revealed a smart internet management system that takes advantage of time to filter content with collective action potential.How and why such a system was institutionalized?We offer a historical institutional analysis to explain the way in which the system evolved.We implement social network analysis to examine the Weibo posts of recurrent events,the elections in Area A in 2016 and 2018,to identify pattern changes in the system.There are two aspects of the changes:the centralization of the command line to a single authority and the implementation of a discriminatory strategy to deal with the various online expressions together forming this intelligent system.The improved Chinese information surveillance system demonstrates both a top-down information management and a bottom-up opinion formation.
基金supported by the National Key Research and Development Program (No. 2017YFB0305300)the National Natural Science Foundation of China (Nos. 51404157, 51374144)+1 种基金Public Welfare Projects of Science and Technology Department of Zhejiang Province (Grant No. 2017C31118)the Natural Science Foundation of Zhejiang Province (Grant No. LY17E050003)
文摘The influence of Cu content on the reaction process, reaction behavior and obtained products in the Cu-ZrC system, as well as their relationships, were investigated. The results showed that Zr C was synthesized through the diffusion and dissolution of C into a Cu-Zr liquid. Increasing the Cu content enhanced the amount of Cu-Zr liquid formed at the early stage but decreased the amount of C atoms dissolving into the melt at unit time. Consequently, the ignition time initially decreased and then increased. Conversely, with an increased Cu content, the energy required for igniting the neighboring unreacted powders increased,while the heat released by the reaction and the dwell time of the compact at high temperatures decreased.These effects then resulted in the reduction of combustion wave velocity, combustion temperature and Zr C particle size. Furthermore, the synthesis of ZrC is a multistage process, which provides a nonuniform distributed Zr C particle size. The sub-μm Zr C particle reinforced Cu matrix composite was fabricated by adding a ZrC-Cu master alloy prepared through a self-propagating high-temperature synthesis reaction into liquid Cu.
