Metallic-monolith catalyst support with self-growing porous anodic alumina(PAA)film was prepared by anodizing Al plate.The effect of hydrothermal treatment(HTT)on the crystalline state and textural properties of PAA f...Metallic-monolith catalyst support with self-growing porous anodic alumina(PAA)film was prepared by anodizing Al plate.The effect of hydrothermal treatment(HTT)on the crystalline state and textural properties of PAA film was investigated by XRD,BET,SEM and TG.The HTT treatment above 50°C and the subsequent calcination above 300°C could convert the amorphous skeleton alumina intoγ-alumina and increase the specific surface area(SBET).However,SEM images showed the HTT modification was a non-uniform process along the thickness of PAA film.The promotion effect of HTT on SBETwas non-linear,and the slope of SBETgradually decreased with the HTT temperature or time increased.The limited HTT effect should be attributed to a changed pore structure caused by an unfavorable pore sealing limitation.Pore widening treatment(PWT)before HTT could break the pore sealing limitation,because of the reduced internal diffusion resistance of hydrothermal reaction.The synergistic combination of PWT and HTT developed a PAA support with a large SBETcomparable to commercialγ-alumina.In the catalytic combustion of toluene,the Pt-based catalyst prepared by using the PWT and HTT comodified PAA support gave higher Pt dispersion and more favorable catalytic activity than that treated by HTT alone.The presence of a bimodal pore structure was suggested to be a decisive reason.展开更多
The continuous development and progress of international economic integration has resulted in the increasing of economic and trade exchanges between various countries.In order to implement a more systematic corporate ...The continuous development and progress of international economic integration has resulted in the increasing of economic and trade exchanges between various countries.In order to implement a more systematic corporate financial supervision mechanism effectively and adapt to the needs of economic development,it is necessary to clarify corporate accounting standards and international financial reporting standards.The relationship between them are crucial to improve the transparency of financial statements and optimize management levels.This paper analyzes the differences between Chinese business accounting standards and international financial reporting standards as well as discusses the convergence process and convergence strategy methods for reference.展开更多
高效、环保、廉价的正极材料被认为是可充电碱性锌电池(RAZBs)的核心要素.据此,本工作开发出一种具有三维有序介孔结构、丰富氮掺杂和氧缺陷的三氧化二铁纳米材料(N-Fe_(2)O_(3)−x).该材料作为一种新型碱性锌电池的正极材料,表现出优异...高效、环保、廉价的正极材料被认为是可充电碱性锌电池(RAZBs)的核心要素.据此,本工作开发出一种具有三维有序介孔结构、丰富氮掺杂和氧缺陷的三氧化二铁纳米材料(N-Fe_(2)O_(3)−x).该材料作为一种新型碱性锌电池的正极材料,表现出优异的性能.N-Fe_(2)O_(3)−x纳米材料采用独特的高等静压纳米铸造工艺和N_(2)等离子体活化方法制备,该材料具有高有效面积、丰富的活性位点、快速的电解质扩散通道和短电荷传输途径.以优化后的N-Fe_(2)O_(3)−x材料为正极,金属锌为负极制备的N-Fe_(2)O_(3)−x//Zn碱性锌电池具有高的容量(288 mA h g^(−1))和能量密度(135 W h kg^(−1),基于活性物质N-Fe_(2)O_(3)−x的重量计算).此外,该可充电锌电池具有良好的稳定性,在10 A g^(−1)电流密度下,1000次循环后仍有73%的电容保持率.该N-Fe_(2)O_(3)−x//Zn电池的电化学性能远远高于目前其他铁基锌电池.本工作首次利用三氧化二铁作为正极材料应用于可充电碱性锌电池的研究,其优良特性将吸引更多研究者的兴趣.展开更多
Aims The mechanisms of plant community assembly are hypothesized to vary at different stages of succession.Here,we explore the local assemblage structure of a herbaceous plant community at its early stage of successio...Aims The mechanisms of plant community assembly are hypothesized to vary at different stages of succession.Here,we explore the local assemblage structure of a herbaceous plant community at its early stage of succession in a supratidal wetland.specifically,we assess the role of Chinese saltcedar(Tamarix chinensis),the lone dominant shrub species,in shaping the spatial structure and species composi-tion in the local plant community,after landscape alteration.Methods We used the multivariate trend-surface analysis for analyzing the spatial structure of the community composition.a null model was also used to detect potential biotic interactions between species.statistical significance was derived from a permutation test by randomizing the presence-absence matrix and functional traits independently.sensitivity analysis by randomly selecting 50 subplots and repeating the null model tests was also done.Finally,rank correlation analysis was used to study the relationship between effect sizes and distance to nearest T.chinensis individuals.Important Findings The herbaceous plant community was highly structured and shaped by the presence of T.chinensis.at local scale,two functional traits,plant height and leaf area,were found to be significantly convergent.Dispersal,environmental stress and interspecific competition played a trivial effect on the local community assembly.The facilitating effect of T.chinensis on the pioneering herbaceous plants,through acting as a wind shelter,was put forward as the dominant community assembly process.展开更多
文摘Metallic-monolith catalyst support with self-growing porous anodic alumina(PAA)film was prepared by anodizing Al plate.The effect of hydrothermal treatment(HTT)on the crystalline state and textural properties of PAA film was investigated by XRD,BET,SEM and TG.The HTT treatment above 50°C and the subsequent calcination above 300°C could convert the amorphous skeleton alumina intoγ-alumina and increase the specific surface area(SBET).However,SEM images showed the HTT modification was a non-uniform process along the thickness of PAA film.The promotion effect of HTT on SBETwas non-linear,and the slope of SBETgradually decreased with the HTT temperature or time increased.The limited HTT effect should be attributed to a changed pore structure caused by an unfavorable pore sealing limitation.Pore widening treatment(PWT)before HTT could break the pore sealing limitation,because of the reduced internal diffusion resistance of hydrothermal reaction.The synergistic combination of PWT and HTT developed a PAA support with a large SBETcomparable to commercialγ-alumina.In the catalytic combustion of toluene,the Pt-based catalyst prepared by using the PWT and HTT comodified PAA support gave higher Pt dispersion and more favorable catalytic activity than that treated by HTT alone.The presence of a bimodal pore structure was suggested to be a decisive reason.
文摘The continuous development and progress of international economic integration has resulted in the increasing of economic and trade exchanges between various countries.In order to implement a more systematic corporate financial supervision mechanism effectively and adapt to the needs of economic development,it is necessary to clarify corporate accounting standards and international financial reporting standards.The relationship between them are crucial to improve the transparency of financial statements and optimize management levels.This paper analyzes the differences between Chinese business accounting standards and international financial reporting standards as well as discusses the convergence process and convergence strategy methods for reference.
基金supported by the National Natural Science Foundation for Young Scientists of China(21805316)the Natural Science Foundation of Hubei Province(2020CFB430)Hubei Provincial Department of Education(Q20192503)。
文摘高效、环保、廉价的正极材料被认为是可充电碱性锌电池(RAZBs)的核心要素.据此,本工作开发出一种具有三维有序介孔结构、丰富氮掺杂和氧缺陷的三氧化二铁纳米材料(N-Fe_(2)O_(3)−x).该材料作为一种新型碱性锌电池的正极材料,表现出优异的性能.N-Fe_(2)O_(3)−x纳米材料采用独特的高等静压纳米铸造工艺和N_(2)等离子体活化方法制备,该材料具有高有效面积、丰富的活性位点、快速的电解质扩散通道和短电荷传输途径.以优化后的N-Fe_(2)O_(3)−x材料为正极,金属锌为负极制备的N-Fe_(2)O_(3)−x//Zn碱性锌电池具有高的容量(288 mA h g^(−1))和能量密度(135 W h kg^(−1),基于活性物质N-Fe_(2)O_(3)−x的重量计算).此外,该可充电锌电池具有良好的稳定性,在10 A g^(−1)电流密度下,1000次循环后仍有73%的电容保持率.该N-Fe_(2)O_(3)−x//Zn电池的电化学性能远远高于目前其他铁基锌电池.本工作首次利用三氧化二铁作为正极材料应用于可充电碱性锌电池的研究,其优良特性将吸引更多研究者的兴趣.
基金National Natural Science Foundation of China(31000197 and 41101169)Knowledge Innovation Project of CAS(KZCX2-EW-QN209)+1 种基金National High Technology Research and Development Program of China(2013AA06A211-4)National Research Foundation of South Africa(89967 and 81825).
文摘Aims The mechanisms of plant community assembly are hypothesized to vary at different stages of succession.Here,we explore the local assemblage structure of a herbaceous plant community at its early stage of succession in a supratidal wetland.specifically,we assess the role of Chinese saltcedar(Tamarix chinensis),the lone dominant shrub species,in shaping the spatial structure and species composi-tion in the local plant community,after landscape alteration.Methods We used the multivariate trend-surface analysis for analyzing the spatial structure of the community composition.a null model was also used to detect potential biotic interactions between species.statistical significance was derived from a permutation test by randomizing the presence-absence matrix and functional traits independently.sensitivity analysis by randomly selecting 50 subplots and repeating the null model tests was also done.Finally,rank correlation analysis was used to study the relationship between effect sizes and distance to nearest T.chinensis individuals.Important Findings The herbaceous plant community was highly structured and shaped by the presence of T.chinensis.at local scale,two functional traits,plant height and leaf area,were found to be significantly convergent.Dispersal,environmental stress and interspecific competition played a trivial effect on the local community assembly.The facilitating effect of T.chinensis on the pioneering herbaceous plants,through acting as a wind shelter,was put forward as the dominant community assembly process.