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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan Li Pengfei Huang Chunyu Cui Xiaoyuan Ma Li Chen Zekun Li Linhai Li yuhong tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

Li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the Li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of Li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a LiF and Li3N-rich solid electrolyte interphase（SEI）.The LiF component increases the robustness of SEI and suppresses the formation of Li dendrites,while the Li3N component facilitates the transportation and reaction kinetics of Li *** a result,the Li‖Li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with LiFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Li metal batteries Li dendrites Electrolyte additive LiF and Li3N-Rich electrode-electrolyte interphase LiFePO4 cathode

Short lifespan and ‘prime period’ of carbon sequestration call for multi-ages in dryland tree plantations

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Forest Ecosystems 2024年第5期11卷 670-676页

作者： Chongyang Xu Xiuchen Wu yuhong tian Liang Shi Yang Qi Jingjing Zhang Hongyan Liu College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes Peking UniversityBeijing100871China College of Resources Science and Technology Beijing Normal UniversityBeijing100875China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China College of JunCao Science and Ecology Fujian Agriculture and Forestry UniversityFuzhou350002China

Enhancing forest cover is important for effective climate change *** suggest that drylands are promising areas for expanding forests,but conflicts arise with increased forest area and water *** tree mortality in drylands raises concerns about carbon sequestration potential in tree *** Chinese dryland tree plantations as an example,we compared their growth with natural *** results suggested plantation trees grew 1.6–2.1 times faster in juvenile phases,significantly shortening time to maturity(13.5 vs.30 years)compared to natural forests,potentially stemming from simple plantation age *** from natural forests,74%of trees in plantations faced growth decline,indicating a short“prime period”for carbon sequestration and even a short ***,a negative relationship between evapotranspiration and tree growth was observed in tree plantations since maturity,leading to high sensitivities of trees to vapor pressure deficit and soil ***,this was not observed in natural *** address this,we suggest afforestation in drylands should consider complex age structures,ensuring a longer prime period for carbon sequestration and life expectancy in tree plantations.

关键词： Tree growth Drylands Tree plantations Carbon sequestration Lifespan

Contributions of different land cover types in Otindag Sandy Land and Bashang area of Hebei Province to the material source of sand stormy weather in Beijing

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Chinese Science Bulletin 2003年第17期48卷 1853-1856页

作者： LIU Hongyan, tian yuhong & DING Deng Department of Ecology, College of Environmental Sciences, Peking University, Beijing 100871, China Department of Ecology College of Environmental Sciences Peking University Beijing China

Different land cover types in Otindag Sandy Land and Bashang area of Hebei Province are linked to a material source of sand stormy weather in Beijing based on results of field vegetation and soil survey and laboratory works. Results of grain size analysis show that dust release potential in per unit area of moving sandy land is small, while lowland meadow and meadow steppe in stony hills have high potential of releasing dusts in per unit area during sand stormy weather occurrence. Further considering the effects of vegetation, it is inferred that the moving sandy land served as a material source of past dust storm and the possi-bility of dust release in per unit area is low in current time. Typical steppe in stony hills is undergoing desertification and its dust release possibility in per unit area is high. Farmland has strong potential of release dusts when they are ploughed in spring, but a large amount of therophytes grow and thus prevent dusts from release when cultivation was terminated. Potentials of dust release in per unit area in fixed sand dunes, stony mountain meadow steppe and lowland meadow are low due to high cover of perennials. Sand dune reactivation and desiccation of lakes and lowlands under estimated future climatic change will make them serve as a future material source of sand stormy weather.

关键词：河北北京沙暴土地覆盖砂地坝上地区材料源

Exposures to temperature beyond threshold disproportionately reduce vegetation growth in the northern hemisphere

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National Science Review 2019年第4期6卷 786-795页

作者： Xiuchen Wu Weichao Guo Hongyan Liu Xiaoyan Li Changhui Peng Craig D.Allen Cicheng Zhang Pei Wang Tingting Pei Yujun Ma yuhong tian Zhaoliang Song Wenquan Zhu Yang Wang Zongshan Li Deliang Chen State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Faculty of Geographical Science Beijing Normal University College of Urban and Environmental Science Peking University Institute of Environment Sciences University of Quebec at Montreal US Geological Survey Fort Collins Science CenterJemez Mountains Field Station Institute of the Surface-Earth System Science Research Tianjin University State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Regional Climate Group Department of Earth SciencesUniversity of Gothenburg

In recent decades, terrestrial vegetation in the northern hemisphere(NH) has been exposed to warming and more extremely high temperatures. However, the consequences of these changes for terrestrial vegetation growth remain poorly quantified and understood. By examining a satellite-based vegetation index, tree-ring measurements and land-surface model simulations, we discovered a consistent convex pattern in the responses of vegetation growth to temperature exposure(TE) for forest, shrub and grass in both the temperate(30?-50?N) and boreal(50?-70?N) NH during the period of 1982-2012. The response of vegetation growth to TE for the three vegetation types in both the temperate and boreal NH increased convergently with increasing temperature, until vegetation type-dependent temperature thresholds were reached. A TE beyond these temperature thresholds resulted in disproportionately weak positive or even strong negative responses. Vegetation growth in the boreal NH was more vulnerable to extremely high-temperature events than vegetation growth in the temporal NH. The non-linear responses discovered here provide new insights into the dynamics of northern terrestrial ecosystems in a warmer world.

关键词： temperature exposure vegetation growth extremely high temperature non-linear response temperate and boreal northern hemisphere

Spatial Distribution of Surface Soil Organic Carbon Density and Related Factors along an Urbanization Gradient in Beijing

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Journal of Resources and Ecology 2020年第5期11卷 508-515页

作者： tian yuhong LIU Fenghua WANG tiantian State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Urban surface soil has a unique set of structures and processes that affect surface soil organic carbon density(SOCdensity) and its spatial variations. Using Beijing as a case study, and assisted by field investigations and experiments, we analyzed the spatial distribution of SOCdensity in different land use types and functional regions, and assessed associated factors such as urbanization level, the physiochemical properties of soil and plant configurations. The present study aims to provide useful information about the mechanisms driving soil organic carbon and climate change in developing and developed areas in urbanized regions like Beijing. Results indicate that P is the main factor positively influencing SOCdensity in most regions. Because of the specific interference directly related to human beings in urban areas, with decreases in the urbanization level, more physiochemical factors of soil can influence SOCdensity. SOCdensity under grasses is not significantly different from that under other plant compositions. Urbanization processes decrease the heterogeneity of the spatial pattern of SOCdensity in most land use types, but increased its contents when the area reached a developed level in Beijing. More factors related to human interference and spatial variation of surface soil carbon storage, especially under impervious land in urban areas, should be considered in future studies.

关键词： soil organic carbon density urbanization soil physiochemical properties plant configuration

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电炉除尘灰作为铁质原料在水泥生产中的应用

钢铁 1998年第6期33卷 61-64页

作者：徐雪峰田玉洪上海五钢(集团)有限公司

系统分析了上海五钢电弧炉冶炼不同钢种时排出烟尘的理化性能，分析结果表明均化后的电炉除尘灰成分稳定，氧化铁含量大于５０％，满足水泥用铁质原料氧化铁含量大于４０％的技术条件。用电炉除尘灰作铁质校正原料，在上海五钢水泥车间... 详细信息

系统分析了上海五钢电弧炉冶炼不同钢种时排出烟尘的理化性能，分析结果表明均化后的电炉除尘灰成分稳定，氧化铁含量大于５０％，满足水泥用铁质原料氧化铁含量大于４０％的技术条件。用电炉除尘灰作铁质校正原料，在上海五钢水泥车间进行了配制４２５号矿渣硅酸盐水泥的工业性试验，生产的水泥质量达到ＧＢ１３４４—９２水泥标准的相关技术指标。

关键词：电炉除尘灰铁质原料水泥工业性试验