Si has been considered as one of the most attractive anode materials for Li-ion batteries(LIBs) because of its high gravimetric and volumetric capacity. Importantly, it is also abundant, cheap, and environmentally ben...Si has been considered as one of the most attractive anode materials for Li-ion batteries(LIBs) because of its high gravimetric and volumetric capacity. Importantly, it is also abundant, cheap, and environmentally benign. In this review, we summarized the recent progress in developments of Si anode materials. First, the electrochemical reaction and failure are outlined, and then, we summarized various methods for improving the battery performance, including those of nanostructuring, alloying, forming hierarchic structures, and using suitable binders. We hope that this review can be of benefit to more intensive investigation of Si-based anode materials.展开更多
The Hala'alat Mountains are located at the transition between the West Junggar and the Junggar Basin. In this area, rocks are Carboniferous, with younger strata above them that have been identified through well data ...The Hala'alat Mountains are located at the transition between the West Junggar and the Junggar Basin. In this area, rocks are Carboniferous, with younger strata above them that have been identified through well data and high-resolution 3D seismic profiles. Among these strata, seven unconformities are observed and distributed at the bases of: the Permian Jiamuhe Formation, the Permian Fengcheng Formation, the Triassic Baikouquan Formation, the Jurassic Badaowan Formation, the Jurassic Xishanyao Formation, the Cretaceous Tugulu Group and the Paleogene. On the basis of balanced sections, these unconformities are determined to have been formed by erosion of uplifts or rotated fault blocks primarily during the Mesozoic and Cenozoic. In conjunction with the currently understood tectonic background of the sur- rounding areas, the following conclusions are proposed: the unconformities at the bases of the Permian Jiamuhe and Fengcheng formations are most likely related to the subduction and closure of the Junggar Ocean during the late Carboniferous-early Permian; the unconformities at the bases of the Triassic Baikoucluan and Jurassic Badaowan formations are closely related to the late Permian Triassic Durbut sinistral slip fault; the unconformities at the bases of the middle Jurassic Xisbanyao Formation and Cretaceous Tugulu Group may be related to reactivation of the Durbut dextral slip fault in the late Jurassic -early Cretaceous, and the unconformity that gives rise to the widely observed absence of the upper Cretaceous in the northern Junggar Basin may be closely related to large scale uplift. All of these geological phenomena indicate that the West Junggar was not calm in the Mesozoic and Cenozoic and that it experienced at least four periods of tectonic movement.展开更多
Supercapacitors(SCs) have attracted much attention as one of the alternative energy devices due to their high power performance,long cycle life,and low maintenance cost.Graphene is considered as an innovative and pr...Supercapacitors(SCs) have attracted much attention as one of the alternative energy devices due to their high power performance,long cycle life,and low maintenance cost.Graphene is considered as an innovative and promising material due to its large theoretical specific surface area,high electrical conductivity,good mechanical properties and chemical stability.Herein,we report an effective strategy for elaborately constructing rationally functionalized self-standing graphene(SG) obtained from giant graphene oxide(GGO) paper followed by an ultrarapid thermal-processing.This treatment results in both the exfoliation of graphene sheets and the reduction of GGO by elimination of oxygencontaining groups.The as-prepared SG electrode materials without additive and conducting agent provide an excellent combination of the electrical double layer capacitor(EDLC) and pseudocapacitor(PC) functions and exhibit superior electrochemical performance,including high specific capacitance,good rate capability and excellent cycling stability when investigated in three-electrode electrochemical cells.展开更多
Stretchable electronic sensing devices are defining the path toward wearable electronics. High-performance flexible strain sensors attached on clothing or human skin are required for potential applications in the ente...Stretchable electronic sensing devices are defining the path toward wearable electronics. High-performance flexible strain sensors attached on clothing or human skin are required for potential applications in the entertainment,health monitoring, and medical care sectors. In this work,conducting copper electrodes were fabricated onpolydimethylsiloxane as sensitive stretchable microsensors by integrating laser direct writing and transfer printing approaches. The copper electrode was reduced from copper salt using laser writing rather than the general approach of printing with pre-synthesized copper or copper oxide nanoparticles. An electrical resistivity of 96 l X cm was achieved on 40-lm-thick Cu electrodes on flexible substrates. The motion sensing functionality successfully demonstrated a high sensitivity and mechanical robustness.This in situ fabrication method leads to a path toward electronic devices on flexible substrates.展开更多
The Wulungu Depression is the northernmost first-order tectonic unit in the Junggar Basin. It can be divided into three sub-units: the Hongyan step-fault zone, the Suosuoquan sag and the Wulungu south slope. The Ceno...The Wulungu Depression is the northernmost first-order tectonic unit in the Junggar Basin. It can be divided into three sub-units: the Hongyan step-fault zone, the Suosuoquan sag and the Wulungu south slope. The Cenozoic strata in the basin are intact and Mesozoic-Cenozoic deformation can be observed in the Wulungu step-fault zone, so this is an ideal place to study the Mesozoic-Cenozoic deformation. By integration of fault-related folding theories, regional geology and drilling data, the strata of the Cretaceous-Paleogene systems are divided into small layers which are selected as the subjects of this research. The combination of the developing unconformity with existing growth strata makes it conceivable that faults on the step-fault zone have experienced different degrees of reactivation of movement since the Cretaceous. Evolutionary analyses of the small layers using 2D-Move software showed certain differences in the reactivation of different segments of the Wulungu Depression such as the timing of reactivation of thrusting, for which the reactivity time of the eastern segment was late compared with those of the western and middle segments. In addition the resurrection strength was similarly slightly different, with the shortening rate being higher in the western segment than in the other segments. Moreover, the thrust fault mechanism is basement-involved combined with triangle shear fold, for which a forward evolution model was proposed.展开更多
Aqueous zinc-ion batteries (AZIBs) have garnered significant research interestas promising next-generation energy storage technologies owing to theiraffordability and high level of safety. However, their restricted io...Aqueous zinc-ion batteries (AZIBs) have garnered significant research interestas promising next-generation energy storage technologies owing to theiraffordability and high level of safety. However, their restricted ionic conductivityat subzero temperatures, along with dendrite formation and subsequentside reactions, unavoidably hinder the implementation of grid-scale applications.In this study, a novel bimetallic cation-enhanced gel polymer electrolyte(Ni/Zn-GPE) was engineered to address these issues. The Ni/Zn-GPE effectivelydisrupted the hydrogen-bonding network of water, resulting in a significantreduction in the freezing point of the electrolyte. Consequently, thedesigned electrolyte demonstrates an impressive ionic conductivity of 28.70 m^(-)cm^(-1) at 20℃. In addition, Ni^(2+) creates an electrostatic shielding interphaseon the Zn surface, which confines the sequential Zn^(2+) nucleation and depositionto the Zn (002) crystal plane. Moreover, the intrinsically high activationenergy of the Zn (002) crystal plane generated a dense and dendrite-free plating/stripping morphology and resisted side reactions. Consequently, symmetricalbatteries can achieve over 2700 hours of reversible cycling at 5 mA cm^(-2),while the Zn jj V_(2)O_(5) battery retains 85.3% capacity after 1000 cycles at -20℃.This study provides novel insights for the development and design of reversiblelow-temperature zinc-ion batteries.展开更多
Fe3O4 is an attractive conversion reactionbased anode material with high theoretical capacity(928 mA h g-1).However,the poor cycling and rate performance hinder its applications in Li-ion batteries.In this work,we rep...Fe3O4 is an attractive conversion reactionbased anode material with high theoretical capacity(928 mA h g-1).However,the poor cycling and rate performance hinder its applications in Li-ion batteries.In this work,we report an effective strategy to synthesize threedimensionally macroporous graphene-supported Fe3O4hybrid composite.Benefiting from advantage of the special structure,the hybrid composite exhibits excellent Li+ storage performance,delivering a high reversible capacity of980 mA h g-1at the current density of 4 A g-1even after470 cycles and ultrahigh rate capability(293 mA h g-1even at current density of 20 A g-1).展开更多
A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressurele...A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the coating.Pre-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated counterpart.Similarly,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±5MPa.The damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape.展开更多
A facile strategy was designed for the fabrication of Fe3O4-nanoparticle- decorated TiO2 nanofiber hierarchical heterostructures (FTHs) by combining the versatility of the electrospinning technique and the hydrother...A facile strategy was designed for the fabrication of Fe3O4-nanoparticle- decorated TiO2 nanofiber hierarchical heterostructures (FTHs) by combining the versatility of the electrospinning technique and the hydrothermal growth method. The hierarchical architecture of Fe3O4 nanoparticles decorated on TiO2 nanofibers enables the successful integration of the binary composite into batteries to address structural stability and low capacity. In the resulting unique architecture of FTHs, the 1D heterostructures relieve the strain caused by severe volume changes of Fe3O4 during numerous charge-discharge cycles, and thus suppress the degradation of the electrode material. As a result, FTHs show excellent performance including higher reversible capacity, excellent cycle life, and good rate performance over a wide temperature range owing to the synergistic effect of the binary composition of TiO2 and Fe304 and the unique features of the hierarchical nanofibers.展开更多
Background:Anopheles gambiae(An.gambiae)is considered the most effective malaria vector worldwide and is widely distributed in Africa.The purpose of this study is to determine the potential impact of climate change on...Background:Anopheles gambiae(An.gambiae)is considered the most effective malaria vector worldwide and is widely distributed in Africa.The purpose of this study is to determine the potential impact of climate change on An.gambiae and predict the present and future potential suitable habitat globally.Methods:In this study,environmental variables,global occurrence data of An.gambiae,and the maximum entropy model(MaxEnt)were used to evaluate the contribution of environmental factors and predict the habitat suitability of An.gambiae under the current and future scenarios.Results:Among all environmental variables,isothermality(Bio3,34.5%)contributed the most to An.gambiae distribution.Under current climate conditions,the potential suitable areas for An.gambiae are mainly located near the equator(approximately 30°N-30°S),with a total area of 16.58 million km2,including central and northern South America,a fraction of areas near the equator of North America,central and southern Africa,some tropical regions of southern Asia,and small areas of Oceania.The areas of potential suitable habitats would be reduced to varying degrees in future climate scenarios.Conclusions:Potential suitable habitats for An.gambiae may not be limited to Africa.Necessary surveillance and preventive measures should be undertaken in high-risk regions,including those outside Africa,to monitor and control the spread of An.gambiae.展开更多
Background Culex pipiens pallens and Culex pipiens quinquefasciatus are the dominant species of Culex mosquitoes in China and important disease vectors.Long-term use of insecticides can cause mutations in the voltage-...Background Culex pipiens pallens and Culex pipiens quinquefasciatus are the dominant species of Culex mosquitoes in China and important disease vectors.Long-term use of insecticides can cause mutations in the voltage-gated sodium channel(vgsc)gene of mosquitoes,but little is known about the current status and evolutionary origins of vgsc gene in different geographic populations.Therefore,this study aimed to determine the current status of vgsc genes in Cx.p.pallens and Cx.p.quinquefasciatus in China and to investigate the evolutionary inheritance of neighboring downstream introns of the vgsc gene to determine the impact of insecticides on long-term evolution.Methods Sampling was conducted from July to September 2021 in representative habitats of 22 provincial-level administrative divisions in China.Genomic DNA was extracted from 1308 mosquitoes,the IIS6 fragment of the vgsc gene on the nerve cell membrane was amplified using polymerase chain reaction,and the sequence was used to evaluate allele frequency and knockdown resistance(kdr)frequency.MEGA 11 was used to construct neighborjoining(NJ)tree.PopART was used to build a TCS network.Results There were 6 alleles and 6 genotypes at the L1014 locus,which included the wild-type alleles TTA/L and CTA/L and the mutant alleles TTT/F,TTC/F,TCT/S and TCA/S.The geographic populations with a kdr frequency less than 20.00%were mainly concentrated in the regions north of 38°N,and the geographic populations with a kdr frequency greater than 80.00%were concentrated in the regions south of 30°N.kdr frequency increased with decreasing latitude.And within the same latitude,the frequency of kdr in large cities is relatively high.Mutations were correlated with the number of introns.The mutant allele TCA/S has only one intron,the mutant allele TTT/F has three introns,and the wild-type allele TTA/L has 17 introns.Conclusions Cx.p.pallens and Cx.p.quinquefasciatus have developed resistance to insecticides in most regions of China.The neighboring downstream introns of the vgsc gene gradually decreased to one intron with the mutation of the vgsc gene.Mutations may originate from multiple mutation events rather than from a single origin,and populations lacking mutations may be genetically isolated.展开更多
Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and t...Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and temporal-spatial distribution of overseas imported dengue fever cases in provincial-level administrative divisions(PLADs)where dengue fever is outbreak in the mainland of China were explored.Methods Using the Chinese National Notifiable Infectious Disease Reporting Information System(CNNDS),we identified overseas imported dengue fever cases in dengue fever outbreak areas in the mainland of China from 2005 to 2019 to draw the epidemic curve and population characteristic distribution of overseas imported cases in each PLAD.Based on spatial autocorrelation analysis of ArcGIS 10.5 and temporal-spatial scanning analysis of SaTScan 9.5,we analyzed the temporal-spatial distribution of overseas imported dengue fever in dengue fever outbreak areas in the mainland of China.Results A total of 11,407 imported cases,mainly from Southeast Asia,were recorded from 2005 to 2019 in these 13 PLADs.Of which 62.1%were imported into Yunnan and Guangdong Provinces.Among the imported cases,there were more males than females,mainly from the 21–50 age group.The hot spots were concentrated in parts of Yunnan,Guangdong and Fujian Provinces.We found the cluster of infected areas were expanding northward.Conclusions Based on the analysis of overseas imported dengue cases in 13 PLADs of the mainland of China from 2005 to 2019,we obtained the epidemiological characteristics and spatial distribution of imported dengue cases.Border controls need to pay attention to key population sectors,such as 21–50 years old men and education of key populations on dengue prevention.There is a need to improve the awareness of the prevention and control of imported cases in border areas.At the same time,northern regions cannot relax their vigilance.展开更多
基金partially supported by Beijing High-level Oversea Talent Projectthe strategic research grant ‘‘Laser interference process of silver nanostructures for surface enhanced Raman spectroscopy and environment application’’ (KZ201410005001) of Beijing Nature Science Foundation, the P. R. China
文摘Si has been considered as one of the most attractive anode materials for Li-ion batteries(LIBs) because of its high gravimetric and volumetric capacity. Importantly, it is also abundant, cheap, and environmentally benign. In this review, we summarized the recent progress in developments of Si anode materials. First, the electrochemical reaction and failure are outlined, and then, we summarized various methods for improving the battery performance, including those of nanostructuring, alloying, forming hierarchic structures, and using suitable binders. We hope that this review can be of benefit to more intensive investigation of Si-based anode materials.
基金financially supported by the National Science and Technology Major Project(Grant No.2011ZX05008-001)the National Natural Science Foundation of China(Grant No.40739906)the Chinese State 973 Project(Grant No.2011CB201100)
文摘The Hala'alat Mountains are located at the transition between the West Junggar and the Junggar Basin. In this area, rocks are Carboniferous, with younger strata above them that have been identified through well data and high-resolution 3D seismic profiles. Among these strata, seven unconformities are observed and distributed at the bases of: the Permian Jiamuhe Formation, the Permian Fengcheng Formation, the Triassic Baikouquan Formation, the Jurassic Badaowan Formation, the Jurassic Xishanyao Formation, the Cretaceous Tugulu Group and the Paleogene. On the basis of balanced sections, these unconformities are determined to have been formed by erosion of uplifts or rotated fault blocks primarily during the Mesozoic and Cenozoic. In conjunction with the currently understood tectonic background of the sur- rounding areas, the following conclusions are proposed: the unconformities at the bases of the Permian Jiamuhe and Fengcheng formations are most likely related to the subduction and closure of the Junggar Ocean during the late Carboniferous-early Permian; the unconformities at the bases of the Triassic Baikoucluan and Jurassic Badaowan formations are closely related to the late Permian Triassic Durbut sinistral slip fault; the unconformities at the bases of the middle Jurassic Xisbanyao Formation and Cretaceous Tugulu Group may be related to reactivation of the Durbut dextral slip fault in the late Jurassic -early Cretaceous, and the unconformity that gives rise to the widely observed absence of the upper Cretaceous in the northern Junggar Basin may be closely related to large scale uplift. All of these geological phenomena indicate that the West Junggar was not calm in the Mesozoic and Cenozoic and that it experienced at least four periods of tectonic movement.
基金supported by 100 Talents Programme of the Chinese Academy of SciencesNational Program on Key Basic Research Project of China(973 Program,Grant No.2012CB215500)+1 种基金Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.20921002 and No.21101147)the Science and Technology Development Program of Jilin Province(Grant No.20100102 and 20116008)
文摘Supercapacitors(SCs) have attracted much attention as one of the alternative energy devices due to their high power performance,long cycle life,and low maintenance cost.Graphene is considered as an innovative and promising material due to its large theoretical specific surface area,high electrical conductivity,good mechanical properties and chemical stability.Herein,we report an effective strategy for elaborately constructing rationally functionalized self-standing graphene(SG) obtained from giant graphene oxide(GGO) paper followed by an ultrarapid thermal-processing.This treatment results in both the exfoliation of graphene sheets and the reduction of GGO by elimination of oxygencontaining groups.The as-prepared SG electrode materials without additive and conducting agent provide an excellent combination of the electrical double layer capacitor(EDLC) and pseudocapacitor(PC) functions and exhibit superior electrochemical performance,including high specific capacitance,good rate capability and excellent cycling stability when investigated in three-electrode electrochemical cells.
基金supported by National Natural Science Foundation of China (51575016)the Beijing Oversea High-Level Talent Project+1 种基金strategic research Grant (KZ20141000500, B-type) of Beijing Natural Science Foundation P.R. Chinathe support by the China Scholarship Council (20160654015) for his research stay at the Institute of Physical and Chemical Research,Wako, Japan
文摘Stretchable electronic sensing devices are defining the path toward wearable electronics. High-performance flexible strain sensors attached on clothing or human skin are required for potential applications in the entertainment,health monitoring, and medical care sectors. In this work,conducting copper electrodes were fabricated onpolydimethylsiloxane as sensitive stretchable microsensors by integrating laser direct writing and transfer printing approaches. The copper electrode was reduced from copper salt using laser writing rather than the general approach of printing with pre-synthesized copper or copper oxide nanoparticles. An electrical resistivity of 96 l X cm was achieved on 40-lm-thick Cu electrodes on flexible substrates. The motion sensing functionality successfully demonstrated a high sensitivity and mechanical robustness.This in situ fabrication method leads to a path toward electronic devices on flexible substrates.
基金financially supported by the National Science and Technology Major Project (No.2011ZX05008-001)the Natural Science Foundation of China (No.40739906)the Chinese State 973 Project(No. 2011CB201100)
文摘The Wulungu Depression is the northernmost first-order tectonic unit in the Junggar Basin. It can be divided into three sub-units: the Hongyan step-fault zone, the Suosuoquan sag and the Wulungu south slope. The Cenozoic strata in the basin are intact and Mesozoic-Cenozoic deformation can be observed in the Wulungu step-fault zone, so this is an ideal place to study the Mesozoic-Cenozoic deformation. By integration of fault-related folding theories, regional geology and drilling data, the strata of the Cretaceous-Paleogene systems are divided into small layers which are selected as the subjects of this research. The combination of the developing unconformity with existing growth strata makes it conceivable that faults on the step-fault zone have experienced different degrees of reactivation of movement since the Cretaceous. Evolutionary analyses of the small layers using 2D-Move software showed certain differences in the reactivation of different segments of the Wulungu Depression such as the timing of reactivation of thrusting, for which the reactivity time of the eastern segment was late compared with those of the western and middle segments. In addition the resurrection strength was similarly slightly different, with the shortening rate being higher in the western segment than in the other segments. Moreover, the thrust fault mechanism is basement-involved combined with triangle shear fold, for which a forward evolution model was proposed.
基金National Natural Science Foundation of China,Grant/Award Number:22075290Natural Science Foundation of Shandong Province,Grant/Award Numbers:ZR2023QB183,ZR2022QB078,ZR2021MB020,ZR2021MB029。
文摘Aqueous zinc-ion batteries (AZIBs) have garnered significant research interestas promising next-generation energy storage technologies owing to theiraffordability and high level of safety. However, their restricted ionic conductivityat subzero temperatures, along with dendrite formation and subsequentside reactions, unavoidably hinder the implementation of grid-scale applications.In this study, a novel bimetallic cation-enhanced gel polymer electrolyte(Ni/Zn-GPE) was engineered to address these issues. The Ni/Zn-GPE effectivelydisrupted the hydrogen-bonding network of water, resulting in a significantreduction in the freezing point of the electrolyte. Consequently, thedesigned electrolyte demonstrates an impressive ionic conductivity of 28.70 m^(-)cm^(-1) at 20℃. In addition, Ni^(2+) creates an electrostatic shielding interphaseon the Zn surface, which confines the sequential Zn^(2+) nucleation and depositionto the Zn (002) crystal plane. Moreover, the intrinsically high activationenergy of the Zn (002) crystal plane generated a dense and dendrite-free plating/stripping morphology and resisted side reactions. Consequently, symmetricalbatteries can achieve over 2700 hours of reversible cycling at 5 mA cm^(-2),while the Zn jj V_(2)O_(5) battery retains 85.3% capacity after 1000 cycles at -20℃.This study provides novel insights for the development and design of reversiblelow-temperature zinc-ion batteries.
基金supported by the Program of ‘‘One Hundred Talents People’’ of the Chinese Academy of Sciencesthe National Basic Research Program of China (2012CB215500)+2 种基金the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (20921002)the National Natural Science Foundation of China (21101147)the Jilin Provincial Science and Technology Development Program (20100102,20116008)
文摘Fe3O4 is an attractive conversion reactionbased anode material with high theoretical capacity(928 mA h g-1).However,the poor cycling and rate performance hinder its applications in Li-ion batteries.In this work,we report an effective strategy to synthesize threedimensionally macroporous graphene-supported Fe3O4hybrid composite.Benefiting from advantage of the special structure,the hybrid composite exhibits excellent Li+ storage performance,delivering a high reversible capacity of980 mA h g-1at the current density of 4 A g-1even after470 cycles and ultrahigh rate capability(293 mA h g-1even at current density of 20 A g-1).
基金financially supported by the National Natural Science Foundation of China(Grant No.51472227)General Technology Promotion Project of Industrial Technology in Basic Public Service Capacity Improvement and Industry Quality(Grant No.0714-EMTC-02-00573/6).
文摘A pre-stressing design and a simple fabrication technology to substantially improve the strength of ceramic components are presented.Residual surface compressive stress is generated in ceramic components by pressureless sintering of a green bulk coated with a thin layer of low coefficient of thermal expansion(CTE).The stress level can be controlled by changing the cross-section area ratio,Young's modulus ratio and CTE ratio of the coating.Pre-stressed ZrO_(2) ceramics coated with Al_(2)O_(3) can achieve a flexural strength of 1330±52MPa,45% higher than their uncoated counterpart.Similarly,the flexural strength of building porcelain tiles is increased by 70%,from 67±3 MPa to 114±5MPa.The damage tolerance of pre-stressed ZrO_(2) ceramics is excellent with a high residual strength of ~1200 MPa in a thermal shock test at 325℃.This simple technique can improve the mechanical performance of ceramic components with no limitation of size and shape.
基金This work is financially supported by the fundamental research funds for the central universities, the National Natural Science Foundation of China (Grant Nos. 51372007 and 21301014).
文摘A facile strategy was designed for the fabrication of Fe3O4-nanoparticle- decorated TiO2 nanofiber hierarchical heterostructures (FTHs) by combining the versatility of the electrospinning technique and the hydrothermal growth method. The hierarchical architecture of Fe3O4 nanoparticles decorated on TiO2 nanofibers enables the successful integration of the binary composite into batteries to address structural stability and low capacity. In the resulting unique architecture of FTHs, the 1D heterostructures relieve the strain caused by severe volume changes of Fe3O4 during numerous charge-discharge cycles, and thus suppress the degradation of the electrode material. As a result, FTHs show excellent performance including higher reversible capacity, excellent cycle life, and good rate performance over a wide temperature range owing to the synergistic effect of the binary composition of TiO2 and Fe304 and the unique features of the hierarchical nanofibers.
基金funded by the National Key R&D Program of China(grant number 2020YFC1200101)Perceptive assessment of health risks caused by climate change,air pollution and health co-benefits of low carbon transition in China(grant number 15LCI1)the Emergency Response Mechanism Operation Program,National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention(grant number 131031102000180007).
文摘Background:Anopheles gambiae(An.gambiae)is considered the most effective malaria vector worldwide and is widely distributed in Africa.The purpose of this study is to determine the potential impact of climate change on An.gambiae and predict the present and future potential suitable habitat globally.Methods:In this study,environmental variables,global occurrence data of An.gambiae,and the maximum entropy model(MaxEnt)were used to evaluate the contribution of environmental factors and predict the habitat suitability of An.gambiae under the current and future scenarios.Results:Among all environmental variables,isothermality(Bio3,34.5%)contributed the most to An.gambiae distribution.Under current climate conditions,the potential suitable areas for An.gambiae are mainly located near the equator(approximately 30°N-30°S),with a total area of 16.58 million km2,including central and northern South America,a fraction of areas near the equator of North America,central and southern Africa,some tropical regions of southern Asia,and small areas of Oceania.The areas of potential suitable habitats would be reduced to varying degrees in future climate scenarios.Conclusions:Potential suitable habitats for An.gambiae may not be limited to Africa.Necessary surveillance and preventive measures should be undertaken in high-risk regions,including those outside Africa,to monitor and control the spread of An.gambiae.
基金funded by the National Science and Technology Major Project of China(No.2018ZX10101002-002)
文摘Background Culex pipiens pallens and Culex pipiens quinquefasciatus are the dominant species of Culex mosquitoes in China and important disease vectors.Long-term use of insecticides can cause mutations in the voltage-gated sodium channel(vgsc)gene of mosquitoes,but little is known about the current status and evolutionary origins of vgsc gene in different geographic populations.Therefore,this study aimed to determine the current status of vgsc genes in Cx.p.pallens and Cx.p.quinquefasciatus in China and to investigate the evolutionary inheritance of neighboring downstream introns of the vgsc gene to determine the impact of insecticides on long-term evolution.Methods Sampling was conducted from July to September 2021 in representative habitats of 22 provincial-level administrative divisions in China.Genomic DNA was extracted from 1308 mosquitoes,the IIS6 fragment of the vgsc gene on the nerve cell membrane was amplified using polymerase chain reaction,and the sequence was used to evaluate allele frequency and knockdown resistance(kdr)frequency.MEGA 11 was used to construct neighborjoining(NJ)tree.PopART was used to build a TCS network.Results There were 6 alleles and 6 genotypes at the L1014 locus,which included the wild-type alleles TTA/L and CTA/L and the mutant alleles TTT/F,TTC/F,TCT/S and TCA/S.The geographic populations with a kdr frequency less than 20.00%were mainly concentrated in the regions north of 38°N,and the geographic populations with a kdr frequency greater than 80.00%were concentrated in the regions south of 30°N.kdr frequency increased with decreasing latitude.And within the same latitude,the frequency of kdr in large cities is relatively high.Mutations were correlated with the number of introns.The mutant allele TCA/S has only one intron,the mutant allele TTT/F has three introns,and the wild-type allele TTA/L has 17 introns.Conclusions Cx.p.pallens and Cx.p.quinquefasciatus have developed resistance to insecticides in most regions of China.The neighboring downstream introns of the vgsc gene gradually decreased to one intron with the mutation of the vgsc gene.Mutations may originate from multiple mutation events rather than from a single origin,and populations lacking mutations may be genetically isolated.
文摘Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and temporal-spatial distribution of overseas imported dengue fever cases in provincial-level administrative divisions(PLADs)where dengue fever is outbreak in the mainland of China were explored.Methods Using the Chinese National Notifiable Infectious Disease Reporting Information System(CNNDS),we identified overseas imported dengue fever cases in dengue fever outbreak areas in the mainland of China from 2005 to 2019 to draw the epidemic curve and population characteristic distribution of overseas imported cases in each PLAD.Based on spatial autocorrelation analysis of ArcGIS 10.5 and temporal-spatial scanning analysis of SaTScan 9.5,we analyzed the temporal-spatial distribution of overseas imported dengue fever in dengue fever outbreak areas in the mainland of China.Results A total of 11,407 imported cases,mainly from Southeast Asia,were recorded from 2005 to 2019 in these 13 PLADs.Of which 62.1%were imported into Yunnan and Guangdong Provinces.Among the imported cases,there were more males than females,mainly from the 21–50 age group.The hot spots were concentrated in parts of Yunnan,Guangdong and Fujian Provinces.We found the cluster of infected areas were expanding northward.Conclusions Based on the analysis of overseas imported dengue cases in 13 PLADs of the mainland of China from 2005 to 2019,we obtained the epidemiological characteristics and spatial distribution of imported dengue cases.Border controls need to pay attention to key population sectors,such as 21–50 years old men and education of key populations on dengue prevention.There is a need to improve the awareness of the prevention and control of imported cases in border areas.At the same time,northern regions cannot relax their vigilance.