This study aims to explore the impact of physical exercise on the anxiety level of college students.We collected physical exercise data and anxiety self-assessment results from college students of different grades,gen...This study aims to explore the impact of physical exercise on the anxiety level of college students.We collected physical exercise data and anxiety self-assessment results from college students of different grades,genders,and ages from multiple universities in Guangdong Province through a questionnaire survey.The study used standardized scales to evaluate participants’physical exercise types,frequencies,intensities,and anxiety levels.The data analysis results showed that there is a significant negative correlation between college students’physical exercise and anxiety level,that is,the more frequent and intense the physical exercise,the lower the anxiety level.In addition,there are differences in the effect of different types of physical exercises on anxiety relief,with aerobic exercises such as running and swimming showing more significant anxiety-relieving effects.The research results provide valuable references for psychological health education and anxiety intervention strategies in universities and suggest promoting physical exercise to effectively alleviate college students’anxiety.展开更多
Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems s...Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge transfer.In this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite film.Specifically,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase.In this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability.Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.展开更多
利用中国华东六省一市13个探空站1961-2017年高空温度数据,对850 h Pa、500 h Pa、200 h Pa高空温度的时间变化特征和空间变化特征进行分析,结果表明:1961-2017年中国华东区域对流层中下层增温趋势明显,向上增温趋势减弱,对流层顶增温...利用中国华东六省一市13个探空站1961-2017年高空温度数据,对850 h Pa、500 h Pa、200 h Pa高空温度的时间变化特征和空间变化特征进行分析,结果表明:1961-2017年中国华东区域对流层中下层增温趋势明显,向上增温趋势减弱,对流层顶增温趋势有所增强。850 h Pa、500 h Pa温度的年代际变化均呈现出先降低后升高的趋势,而200 h Pa温度的年代际变化则呈现持续升高的趋势。秋、冬季在各个层次上均为显著的增温趋势,冬季的增温趋势明显大于其他季节,500 h Pa春季和200 h Pa夏季有微弱的降温趋势。不同层次年平均气温的空间分布均有明显的南北差异,且随着高度的增加,南北平均温差先增大后减小。850 h Pa、500 h Pa年平均温度的空间变化趋势一定程度上呈现出华东沿海地区增温趋势大于内陆的特征,200 h Pa则呈现华东南部的增温趋势大于北部的特征。850 h Pa各季节呈现出中国华东沿海地区增温、内陆增温趋势不如沿海地区或内陆呈现降温趋势,500 h Pa的春季和200 h Pa的夏、秋季则呈现出中国华东南部地区增温、北部地区降温的趋势。展开更多
Sn-based perovskite solar cells(PSCs)demonstrate a potential development in eco-friendly devices due to their hypotoxicity.However,poor stability and crystalline quality are still the challenges for achieving high-per...Sn-based perovskite solar cells(PSCs)demonstrate a potential development in eco-friendly devices due to their hypotoxicity.However,poor stability and crystalline quality are still the challenges for achieving high-performance and long-term operating devices.In this work,inspired by biological protein,nickelporphyrin(Ni-P)with electron cloud on conjugate ring is applied into Sn-based perovskite to prevent perovskite from being eroded.The synergistic effect of water and oxygen is broken in grain boundaries and surface so that the stability of PSCs can be improved obviously,despite there is hardly any barrier for water to erode.Simultaneously,the electron-rich molecules can passivate the defects of perovskite such as iodine vacancy.Moreover,the ester group in Ni-P molecule can bind with SnI;to form complex and then restrain nucleation.Combining with the template effect of 2D molecular,the crystallization of perovskite films is optimized.Therefore,the Sn-based PSCs with Ni-P achieve a stabilized power conversion efficiency(PCE)of 7.79%with negligible hysteresis in fexible devices,respectively.Moreover,the PSCs can maintain 80%of the pristine PCE after 300 h under air environment.展开更多
Currently,highly efficient n-i-p perovskite solar cells rely on an organic interface layer for high efficiency,especially 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)ami-no]-9,9′-spirobifluorene(spiro-OMeTAD),...Currently,highly efficient n-i-p perovskite solar cells rely on an organic interface layer for high efficiency,especially 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)ami-no]-9,9′-spirobifluorene(spiro-OMeTAD),but the instability of organic materials in the photothermal field compromises device stability.In this study,we employ the oleic acid(YS)/oleamine(YA)end-sealing method to achieve uniform dispersion of NiO_(X)nanoparticles,effectively mitigating coagulation resulting from high local concentration and secondary motion adsorption.Furthermore,the conductivity of the hole transport layer and its energy level alignment with perovskite is enhanced by the additional 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone(F4TCNQ),leading to a remarkable improvement of open-circuit voltage and fill factor,thus the high efficiency of 25.17%and 24.36%on 0.1 and 1.01cm2,respectively.Moreover,by realizing an all-inorganic interface layer,an initial efficiency exceeding 90%is maintained even after 2,800 h of heating at 85℃.展开更多
In recent years,perovskite solar cells(PSCs)have gone through unparalleled rapid expansion and become a candidate for solar cells.Among various PSCs,though typical three-dimensional(3D)halide perovskite-based PSCs del...In recent years,perovskite solar cells(PSCs)have gone through unparalleled rapid expansion and become a candidate for solar cells.Among various PSCs,though typical three-dimensional(3D)halide perovskite-based PSCs deliver the highest efficiency,they are subjected to severe instability,which constrains their commercializability.In comparison,two-dimensional(2D)PSCs have aroused widespread concern due to their superior stability.After that,2D/3D perovskite materials combining high efficiency and good stability have emerged as the times require,which are expected to bring about stable and efficient PSCs.Here,this review focuses on selection of functional spacer cations for efficient and stable 2D/3D PSCs.First,the unique function of different spacer groups and the selection of appropriate spacer cations in 2D perovskites is summarized and proposed.Then,by selecting appropriate cations,the role of 2D perovskites is elaborated,including energy level regulation,ion migration suppression,defect passivation,residual stress release and improved stability.In addition,the preparation methods of 2D/3D perovskites are comprehensively summarized.Finally,current challenges and future opportunities for the further development of 2D/3D perovskites for solar cells are discussed and prospected.展开更多
A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene con...A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene constellation with a Clade 2.3.2.1c HA,a H9N2-derived PB2 gene and the other six genes of Asian H5N1-origin.The Clade 2.3.2.1c H5N1 reassortants displayed a high genetic relationship to a human H5N1 strain(A/Alberta/01/2014).Further analysis showed that similar viruses have been circulating in wild birds in China,Russia,Dubai(Western Asia),Bulgaria and Romania(Europe),as well as domestic poultry in some regions of Africa.The affected areas include the Central Asian,East Asian-Australasian,West Asian-East African,and Black Sea/Mediterranean flyways.These results show that the novel Clade 2.3.2.1c reassortant viruses are circulating worldwide and may have gained a selective advantage in migratory birds,thus posing a serious threat to wild birds and potentially humans.展开更多
The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the e...The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the environmental degradation and ductile cracks of perovskite films usually begin at the grain boundaries(GBs).Herein,sulfonated graphene oxide(s-GO)is employed to construct a cementitious GBs by interacting with the[Pb I6]4–at GBs.The resultant s-GO-[Pb I6]4–complex can effectively passivate the defects of vacant iodine,and the devices with s-GO exhibit remarkable waterproofness and flexibility due to the tough and water-insoluble GBs.The champion PCE of 20.56%(1.01 cm^(2))in a device treated with s-GO is achieved.This device retains 90%of its original PCE after 180 d stored in the ambient condition,as well as over 80%retention after 10,000 bending cycles at a curvature radius of 3 mm.展开更多
基金Zhaoqing Education Development Research Institute“Psychological Mechanism and Intervention Research on the Impact of Sports on College Students’Anxiety”(ZQJKY2023211)。
文摘This study aims to explore the impact of physical exercise on the anxiety level of college students.We collected physical exercise data and anxiety self-assessment results from college students of different grades,genders,and ages from multiple universities in Guangdong Province through a questionnaire survey.The study used standardized scales to evaluate participants’physical exercise types,frequencies,intensities,and anxiety levels.The data analysis results showed that there is a significant negative correlation between college students’physical exercise and anxiety level,that is,the more frequent and intense the physical exercise,the lower the anxiety level.In addition,there are differences in the effect of different types of physical exercises on anxiety relief,with aerobic exercises such as running and swimming showing more significant anxiety-relieving effects.The research results provide valuable references for psychological health education and anxiety intervention strategies in universities and suggest promoting physical exercise to effectively alleviate college students’anxiety.
基金support from the National Natural Science Foundation of China(NSFC)(52163019,22005131,52173169 and U20A20128)support from the Natural Science Foundation of Jiangxi Province(20224ACB214006)。
文摘Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge transfer.In this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite film.Specifically,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase.In this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability.Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.
文摘利用中国华东六省一市13个探空站1961-2017年高空温度数据,对850 h Pa、500 h Pa、200 h Pa高空温度的时间变化特征和空间变化特征进行分析,结果表明:1961-2017年中国华东区域对流层中下层增温趋势明显,向上增温趋势减弱,对流层顶增温趋势有所增强。850 h Pa、500 h Pa温度的年代际变化均呈现出先降低后升高的趋势,而200 h Pa温度的年代际变化则呈现持续升高的趋势。秋、冬季在各个层次上均为显著的增温趋势,冬季的增温趋势明显大于其他季节,500 h Pa春季和200 h Pa夏季有微弱的降温趋势。不同层次年平均气温的空间分布均有明显的南北差异,且随着高度的增加,南北平均温差先增大后减小。850 h Pa、500 h Pa年平均温度的空间变化趋势一定程度上呈现出华东沿海地区增温趋势大于内陆的特征,200 h Pa则呈现华东南部的增温趋势大于北部的特征。850 h Pa各季节呈现出中国华东沿海地区增温、内陆增温趋势不如沿海地区或内陆呈现降温趋势,500 h Pa的春季和200 h Pa的夏、秋季则呈现出中国华东南部地区增温、北部地区降温的趋势。
基金support from the National Natural Science Foundation of China(NSFC)(22005131,52173169 and 11564025)。
文摘Sn-based perovskite solar cells(PSCs)demonstrate a potential development in eco-friendly devices due to their hypotoxicity.However,poor stability and crystalline quality are still the challenges for achieving high-performance and long-term operating devices.In this work,inspired by biological protein,nickelporphyrin(Ni-P)with electron cloud on conjugate ring is applied into Sn-based perovskite to prevent perovskite from being eroded.The synergistic effect of water and oxygen is broken in grain boundaries and surface so that the stability of PSCs can be improved obviously,despite there is hardly any barrier for water to erode.Simultaneously,the electron-rich molecules can passivate the defects of perovskite such as iodine vacancy.Moreover,the ester group in Ni-P molecule can bind with SnI;to form complex and then restrain nucleation.Combining with the template effect of 2D molecular,the crystallization of perovskite films is optimized.Therefore,the Sn-based PSCs with Ni-P achieve a stabilized power conversion efficiency(PCE)of 7.79%with negligible hysteresis in fexible devices,respectively.Moreover,the PSCs can maintain 80%of the pristine PCE after 300 h under air environment.
基金support from the National Natural Science Foundation of China(U20A20128,52173169,52222312)the Natural Science Foundation of Jiangxi Province(20231ZDH04036,20212BAB214055,20224ACB204007)。
文摘Currently,highly efficient n-i-p perovskite solar cells rely on an organic interface layer for high efficiency,especially 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)ami-no]-9,9′-spirobifluorene(spiro-OMeTAD),but the instability of organic materials in the photothermal field compromises device stability.In this study,we employ the oleic acid(YS)/oleamine(YA)end-sealing method to achieve uniform dispersion of NiO_(X)nanoparticles,effectively mitigating coagulation resulting from high local concentration and secondary motion adsorption.Furthermore,the conductivity of the hole transport layer and its energy level alignment with perovskite is enhanced by the additional 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone(F4TCNQ),leading to a remarkable improvement of open-circuit voltage and fill factor,thus the high efficiency of 25.17%and 24.36%on 0.1 and 1.01cm2,respectively.Moreover,by realizing an all-inorganic interface layer,an initial efficiency exceeding 90%is maintained even after 2,800 h of heating at 85℃.
基金the support from the National Natural Science Foundation of China(NSFC)(U20A20128,52263027,22379060,52173169 and 52222312)the"Double Thousand Plan"Science and Technology Innovation High-end Talent Project of Jiangxi Province(jxsq2019201049)+2 种基金the Natural Science Foundation of Jiangxi Province(20231ZDH04036,20212BAB214055 and 20224ACB204007)China National Postdoctoral Program for Innovative Talents(BX2021117)China Postdoctoral Science Foundation(2021M700060)。
基金support from the National Natural Science Foundation of China(NSFC)(grant nos.52163019,22005131,52173169,and U20A20128)support from the China Postdoctoral Science Foundation(grant no.2021M700060)the Postdoctoral Innovative Talents Support Program(grant no.BX2021117).
文摘In recent years,perovskite solar cells(PSCs)have gone through unparalleled rapid expansion and become a candidate for solar cells.Among various PSCs,though typical three-dimensional(3D)halide perovskite-based PSCs deliver the highest efficiency,they are subjected to severe instability,which constrains their commercializability.In comparison,two-dimensional(2D)PSCs have aroused widespread concern due to their superior stability.After that,2D/3D perovskite materials combining high efficiency and good stability have emerged as the times require,which are expected to bring about stable and efficient PSCs.Here,this review focuses on selection of functional spacer cations for efficient and stable 2D/3D PSCs.First,the unique function of different spacer groups and the selection of appropriate spacer cations in 2D perovskites is summarized and proposed.Then,by selecting appropriate cations,the role of 2D perovskites is elaborated,including energy level regulation,ion migration suppression,defect passivation,residual stress release and improved stability.In addition,the preparation methods of 2D/3D perovskites are comprehensively summarized.Finally,current challenges and future opportunities for the further development of 2D/3D perovskites for solar cells are discussed and prospected.
基金financially supported by the National Natural Science Foundation of China(NSFC,52163019,22005131,52173169 and U20A20128)the support from the Postdoctoral Innovative Talents Support Program(BX2021117)+1 种基金China Postdoctoral Science Foundation(2021M700060)the Graduate Students Innovation Special Foundation of Jiangxi Province(YC2022-B009)。
基金supported by grants from the National Natural Science Foundation of China (31311120063,81470096,31570026,31471253)the Ministry of Education and Science of the Russian Federation (Chinese-Russian project:RFMEFI61315X0045)+3 种基金the intramural special grant for influenza virus research from the Chinese Academy of Sciences (KJZD-EW-L09)the IDRCAPEIR program (106915-001)Special Project of Ministry of Science and Technology (2013FY113500)supported by the “Taishan Scholar” project of Shandong Province
文摘A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene constellation with a Clade 2.3.2.1c HA,a H9N2-derived PB2 gene and the other six genes of Asian H5N1-origin.The Clade 2.3.2.1c H5N1 reassortants displayed a high genetic relationship to a human H5N1 strain(A/Alberta/01/2014).Further analysis showed that similar viruses have been circulating in wild birds in China,Russia,Dubai(Western Asia),Bulgaria and Romania(Europe),as well as domestic poultry in some regions of Africa.The affected areas include the Central Asian,East Asian-Australasian,West Asian-East African,and Black Sea/Mediterranean flyways.These results show that the novel Clade 2.3.2.1c reassortant viruses are circulating worldwide and may have gained a selective advantage in migratory birds,thus posing a serious threat to wild birds and potentially humans.
基金support from the National Natural Science Foundation of China(NSFC)(51673091,51833004,and 51425304)NSFC-Guangdong Joint funding(U1801256)+2 种基金support from the National Key R&D Program of China(2018YFA0208501)the National Natural Science Foundation of China(51803217,91963212,51961145102,and 51773206)K.C.Wong Education Foundation。
文摘The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the environmental degradation and ductile cracks of perovskite films usually begin at the grain boundaries(GBs).Herein,sulfonated graphene oxide(s-GO)is employed to construct a cementitious GBs by interacting with the[Pb I6]4–at GBs.The resultant s-GO-[Pb I6]4–complex can effectively passivate the defects of vacant iodine,and the devices with s-GO exhibit remarkable waterproofness and flexibility due to the tough and water-insoluble GBs.The champion PCE of 20.56%(1.01 cm^(2))in a device treated with s-GO is achieved.This device retains 90%of its original PCE after 180 d stored in the ambient condition,as well as over 80%retention after 10,000 bending cycles at a curvature radius of 3 mm.
