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Highly efficient mixed-metal spinel cobaltite electrocatalysts for the oxygen evolution reaction

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Chinese Journal of Catalysis 2020年第12期41卷 1855-1863页

作者： leiming tao Penghu Guo Weiling Zhu Tianle Li Xiantai Zhou Yongqing Fu Changlin Yu Hongbing Ji School of Science Guangdong University of Petrochemical TechnologyMaoming 525000GuangdongChina Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074HubeiChina Faculty of Engineering and Environment Northumbria UniversityNewcastle upon TyneNE18STUK Fine Chemical Industry Research Institute School of ChemistrySun Yat‐sen UniversityGuangzhou 510275GuangdongChina

Cation substitution in spinel cobaltites(e.g.,ACo2O4,in which A=Mn,Fe,Co,Ni,Cu,or Zn)is a promising strategy to precisely modulate their electronic structure/properties and thus improve the corresponding electrochemical performance for water ***,the fundamental principles and mechanisms are not fully *** research aims to systematically investigate the effects of cation substitution in spinel cobaltites derived from mixed-metal-organic frameworks on the oxygen evolution reaction(OER).Among the obtained ACo2O4 catalysts,FeCo2O4 showed excellent OER performance with a current density of 10 mA·cm^-2 at an overpotential of 164 mV in alkaline *** theoretical calculations and experimental results demonstrate that the Fe substitution in the crystal lattice of ACo2O4 can significantly accelerate charge transfer,thereby achieving enhanced electrochemical *** crystal field of spinel ACo2O4,which determines the valence states of cations A,is identified as the key factor to dictate the OER performance of these spinel cobaltites.

关键词： Cation-substituted spinel cobaltites Crystal field Oxygen evolution reaction Water-splitting Electrocatalysis

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Seasonal variations of mass absorption efficiency of elemental carbon in PM_(2.5) in urban Guangzhou of South China

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Journal of Environmental Sciences 2023年第11期133卷 83-92页

作者： Chenglei Pei Yunfei Wu Jun tao leiming Zhang tao Zhang Runqi Zhang Sheng Li State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center Guangzhou 518049China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute for Environmental and Climate Research Jinan UniversityGuangzhou 510632China Air Quality Research Division Science and Technology BranchEnvironment and Climate Change CanadaTorontoCanada Guangdong Ecological and Environmental Monitoring Center Guangzhou 510308China

This study investigates seasonal variations of mass absorption efficiency of elemental carbon(MAE_(EC))and possible influencing factors in urban Guangzhou of South *** concentrations of elemental carbon(EC)and organic carbon(OC)in PM_(2.5) and aerosol absorption coefficient(b_(ap))at multi-wavelengths were simultaneously measured in four seasons of 2018-2019 at hourly resolution by a semi-continuous carbon analyzer and an *** average mass concentrations of EC were in the range of 1.36-1.70μgC/m^(3) with a lower value in summer than in the other seasons,while those of OC were in the range of 4.70–6.49μgC/m^(3) with the lowest value in summer and the highest in *** exhaust from local traffic was identified to be the predominant source of carbonaceous *** average aerosol absorption Angstrom exponents(AAE)were lower than 1.2 in four seasons,indicating EC and b_(ap) were closely related with vehicle *** MAE EC at 550 nm was 11.0,8.5,10.4 and 11.3 m^(2)/g in spring,summer,autumn,and winter,*** MAE EC was related with the high mass ratio of non-carbonaceous aerosols to EC and high ambient relative humidity.

关键词： Vehicle exhaust Non-carbonaceous aerosols Absorption enhancement Relative humidity

Fe2O3-FeO-MgO-O2体系中二价金属氧化物形成的热力学分析

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广东石油化工学院学报 2020年第4期30卷 59-63页

作者：薛鹏陶磊明李天乐朱伟玲贺东风广东石油化工学院理学院广东茂名525000 北京科技大学冶金与生态工程学院北京100083

采用Factsage热力学软件模拟了Fe2O3-FeO-MgO-O2体系中二价金属氧化物(RO相)的形成过程,包括不同成分、不同温度和不同氧分压对RO相形成过程的影响,并对RO相中各组元的活度进行了模拟计算。结果表明,随原料中Fe2O3含量的增加,RO相的开... 详细信息

采用Factsage热力学软件模拟了Fe2O3-FeO-MgO-O2体系中二价金属氧化物(RO相)的形成过程,包括不同成分、不同温度和不同氧分压对RO相形成过程的影响,并对RO相中各组元的活度进行了模拟计算。结果表明,随原料中Fe2O3含量的增加,RO相的开始熔化温度逐渐降低。模拟形成的RO相由MgO、Fe2O3和FeO组成,并且随温度升高,体系中Fe2O3逐渐失去O转变成FeO。在1650℃条件下,原料中Fe2O3含量的增加能够提高RO相中Fe2O3和FeO的活度,降低MgO的活度。降低氧分压能够加速Fe2O3向FeO转变,当氧分压从21.278 kPa降到1.013×10^-6kPa,RO相中的Fe2O3能够降到1.96 g以下,Fe元素主要以FeO的形式存在,模拟计算得到的RO相的成分更接近实际转炉渣中RO相的成分。

关键词：二价金属氧化物 RO相 Factsage 热力学分析

Early selection efficiency for fiber dimensions and their relationships with growth and wood quality for Pinus elliotth *** southern China

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Journal of Forestry Research 2023年第6期34卷 1951-1962页

作者： Jing Wen Min Yi leiming Dong Lu Zhang Siyu Liu Shenggui Yuan Xiaoxiao tao Meng Lai Key Laboratory of Silviculture College of ForestryJiangxi Agricultural UniversityNanchang 330045People’s Republic of China Beijing Floriculture Engineering Technology Research Centre Beijing Botanical GardenBeijing 100093People’s Republic of China

A solid understanding of the efficiency of early selection for fiber dimensions is a prerequisite for breeding slash pine(Pinus elliottii Engelm.)with improved properties for pulp and paper *** correlations between size of fibers,wood quality and growth properties are also *** accomplish effective early selection for size of fibers and evaluate the impact for wood quality traits and ring widths,core samples were collected from360 trees of 20 open-pollinated Pinus elliottii families from three genetic *** were measured by SilviScan,and the age trends for phenotypic values,heritability,early-late genetic correlations,and early selection efficiency for fiber dimensions,such as tangential and radial fiber widths,fiber wall thickness and fiber coarseness,and their correlations with microfibril angle(MFA),modulus of elasticity(MOE),wood density and ring width were *** phenotypic trends were found for tangential and radial fiber widths while fiber coarseness and wall thickness curves were *** trends of heritability based on area-weighted fiber dimensions were *** to moderate heritability from pith to bark(~0.5)was found for all fiber dimension across the three sites except for tangential fiber width and wall thickness at the Ganzhou ***-late genetic correlations were 0.9 after age of 9 years,and early selection for fiber dimensions could be effective due to strong genetic *** results showed moderate to strong positive genetic correlations for modulus of elasticity and density with fiber *** effects on fiber dimensions were weak or moderate when ring width or wood quality traits were selected *** of efficiency for early selection indicated that the optimal age for radial fiber width and fiber coarseness was 6-7 years,while for tangential fiber width and wall thickness was 9-10 years.

关键词： Pinus elliottii Early selection efficiency Genetic correlation Heritability Fiber dimensions

Observation and analysis of near-surface atmospheric aerosol optical properties in urban Beijing

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Particuology 2015年第1期13卷 144-154页

作者： Junshan Jing Yunfei Wu Jun tao Huizheng Che Xiangao Xia Xiaochun Zhang Peng Yan Deming Zhao leiming Zhang Centre for Atmosphere Watch and Services Meteorological Observation Centre of China Meteorological Administration Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences South China Institute of Environmental Sciences Ministry of Environmental Protection Key Laboratory of Atmospheric Chemistry Centre for Atmosphere Watch and ServicesChinese Academy of Meteorological Sciences Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Air Quality Research Division Science and Technology BranchEnvironment Canada

Year-round measurements of the mass concentration and optical properties of fine aerosols （PM2s） from June 2009 to May 2010 at an urban site in Beijing were analyzed. The annual mean values of the PM2.5 mass concentration, absorption coefficient （Ab）, scattering coefficient （Sc） and single scattering albedo （SSA） at 525 nm were 67 ± 66 μg/m^3, 64 ± 62 Mm^-1, 360±405 Mm^-1 and 0.82±0.09, respectively. The bulk mass absorption efficiency and scattering efficiency of the PM2.5 at 525 nm were 0.78 m^2/g and 5.55 m^2]g, respectively. The Ab and Sc showed a similar diurnal variation with a maximum at night and a minimum in the afternoon, whereas SSA displayed an opposite diurnal pattern. Significant increases in the Ab and Sc were observed in pollution episodes caused by the accumulation of pollutants from both local and regional sources under unfavorable weather conditions. Aerosol loadings in dust events increased by several times in the spring, which had limited effects on the Ab and Sc due to the low absorption and scattering efficiency of dust particles. The frequency of haze days was the highest in autumn because of the high aerosol absorption and scattering under unfavorable weather conditions. The daily PM2.5 concentration should be controlled to a level lower than 64 μg/m^3 to prevent the occurrence of haze days according to its exponentially decreased relationship with visibility.

关键词： PM2.5 Aerosol optical properties Haze Visibility

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热透镜效应及其焦距测量研究

广东石油化工学院学报 2020年第3期30卷 65-69页

作者：李春威韩太坤郑晓艳庄海宁蔡汝敏吴伟韩陶磊明广东石油化工学院理学院广东茂名525000

在激光器的设计和应用中,需要考虑热透镜效应影响,然而准确测出低功率激光器的热透镜焦距是研究难点。本实验选用低功率He-Ne激光器,通过研究放大光斑的光强变化观察热透镜效应,并推导出热透镜焦距的公式。对比丙酮和乙醇溶剂,观察发现... 详细信息

在激光器的设计和应用中,需要考虑热透镜效应影响,然而准确测出低功率激光器的热透镜焦距是研究难点。本实验选用低功率He-Ne激光器,通过研究放大光斑的光强变化观察热透镜效应,并推导出热透镜焦距的公式。对比丙酮和乙醇溶剂,观察发现丙酮具有更明显的热透镜效应,测试计算丙酮的热透镜焦距为-1.6 m。研究有助于改进低功率激光器的设计,从而降低热透镜效应的影响,提高激光器的性能。

关键词： He-Ne激光器热透镜效应热透镜焦距丙酮

双探头SPECT对向平面显像放射性活度定量的模型研究

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核技术 2005年第11期28卷 859-862页

作者：郭雷鸣陈涛孙晓光黄钢上海第二医科大学附属仁济医院核医学科

放射性核素体内吸收剂量估测是评价辐射危害和内照射治疗价值的重要指标。器官组织的绝对活度定量是吸收剂量估算的必要步骤。本研究采用双探头单光子发射型计算机断层显像术(Singlephotonemissioncomputedtomography,SPECT)对向测定对... 详细信息

放射性核素体内吸收剂量估测是评价辐射危害和内照射治疗价值的重要指标。器官组织的绝对活度定量是吸收剂量估算的必要步骤。本研究采用双探头单光子发射型计算机断层显像术(Singlephotonemissioncomputedtomography,SPECT)对向测定对模拟的99Tcm源器官进行了活度定量的模型实验。结果表明:双探头SPECT对向平面显像放射性活度定量不受放射源在体模内深度的影响,并且在放射源直径≤2cm时活度定量最准确;Buijs法提供了最准确且最稳定的本底校正方法。

关键词：单光子发射型计算机断层显像术定量平面显像活度定量拟人模型

白云石和硫酸亚铁复配对城市污泥中重金属形态分布及生物有效性的影响

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环境工程学报 2018年第2期12卷 654-662页

作者：陶祥运李磊明刘小红司友斌安徽农业大学资源与环境学院农田生态保育与污染防控安徽省重点实验室合肥230036

以合肥市某污水处理厂污泥为研究对象,研究白云石、硫酸亚铁以及白云石和硫酸亚铁复合物作为改良剂对污泥重金属形态和生物有效性的影响,并对其钝化机理进行了初步研究。结果表明:白云石可以提高污泥pH,硫酸亚铁则降低污泥的pH,白云石... 详细信息

以合肥市某污水处理厂污泥为研究对象,研究白云石、硫酸亚铁以及白云石和硫酸亚铁复合物作为改良剂对污泥重金属形态和生物有效性的影响,并对其钝化机理进行了初步研究。结果表明:白云石可以提高污泥pH,硫酸亚铁则降低污泥的pH,白云石和硫酸亚铁复配添加时,污泥pH变化并不显著。白云石对污泥中Cu和Cd有较好钝化作用,硫酸亚铁对污泥中As具有显著钝化作用,白云石和铁盐复配对污泥中重金属Cu、Zn、Cd和As均有显著钝化作用。白云石和硫酸亚铁处理可显著降低污泥中重金属有效态含量,其中以5%白云石和5%硫酸亚铁复配处理的效果最好,与对照相比,污泥中的有效Cu、Zn、Cd和As分别减少了59.58%、42.26%、40.93%和55.68%。SEM-EDS和Visual MINTEQ模拟结果显示,白云石中的碳酸根离子能够与重金属发生沉淀反应。盆栽实验结果显示,污泥中加入白云石和硫酸亚铁后,青菜地上部和根部重金属含量降低,地上部Cu、Zn、Cd和As最大降低程度分别为53.56%、34.51%、57.29和77.04%。

关键词：城市污泥白云石硫酸亚铁重金属形态生物有效性

Spatial patterns of terrestrial net ecosystem productivity in China during 1981―2000

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Science China Earth Sciences 2007年第5期50卷 745-753页

作者： tao Bo1, CAO MingKui1, LI KeRang1, GU FengXue1, JI JinJun1,2, HUANG Mei1 & ZHANG leiming1 1 Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100101, China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

As the third largest country in the world, China has highly variable environmental condition and eco- logical pattern in both space and time. Quantification of the spatial-temporal pattern and dynamic of terrestrial ecosystem carbon cycle in China is of great significance to regional and global carbon budget. In this study, we used a high-resolution climate database and an improved ecosystem process-based model to quantify spatio-temporal pattern and dynamic of net ecosystem productivity (NEP) in China and its responses to climate change during 1981 to 2000. The results showed that NEP increased from north to south and from northeast to southwest. Positive NEP (carbon sinks) occurred in the west of Southwest China, southeastern Tibet, Sanjiang Plain, Da Hinggan Mountains and the mid-west of North China. Negative NEP (carbon sources) were mainly found in Central China, the south of Southwest China, the north of Xinjiang, west and north of Inner Mongolia, and parts of North China. From the 1980s to 1990s, the increasing trend of NEP occurred in the middle of Northeast China Plain and the Loess Plateau and decreasing trends mainly occurred in a greater part of Central China. In the study period, natural forests had minimal carbon uptake, while grassland and shrublands accounted for nearly three fourths of the total carbon terrestrial uptakes in China during 1981―2000.

关键词： China terrestrial ecosystem carbon cycle spatial patterns climate change