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| 1 | Linking atmospheric pollution to cryospheric change in the Third Pole region: current progress and future prospects显示文摘The Tibetan Plateau and its surroundings are known as the Third Pole(TP). This region is noted for its high rates of glacier melt and the associated hydrological shifts that affect water supplies in Asia. Atmospheric pollutants contribute to climatic and cryospheric changes through their effects on solar radiation and the albedos of snow and ice surfaces; moreover, the behavior and fates within the cryosphere and environmental impacts of environmental pollutants are topics of increasing concern. In this review, we introduce a coordinated monitoring and research framework and network to link atmospheric pollution and cryospheric changes(APCC) within the TP region. We then provide an up-to-date summary of progress and achievements related to the APCC research framework, including aspects of atmospheric pollution’s composition and concentration, spatial and temporal variations, trans-boundary transport pathways and mechanisms, and effects on the warming of atmosphere and changing in Indian monsoon, as well as melting of glacier and snow cover. We highlight that exogenous air pollutants can enter into the TP’s environments and cause great impacts on regional climatic and environmental changes. At last, we propose future research priorities and map out an extended program at the global scale. The ongoing monitoring activities and research facilitate comprehensive studies of atmosphere–cryosphere interactions, represent one of China’s key research expeditions to the TP and the polar regions and contribute to the global perspective of earth system science. | Shichang Kang Qianggong Zhang Yun Qian Zhenming Ji Chaoliu Li Zhiyuan Cong Yulan Zhang Junming Guo Wentao Du Jie Huang Qinglong You Arnico K.Panday Maheswar Rupakheti Deliang Chen Orjan Gustafsson Mark H.Thiemens Dahe Qin | 2019 | National Science Review2019，6，4： | 35 |
| 2 | Distribution and transportation of mercury from glacier to lake in the Qiangyong Glacier Basin, southern Tibetan Plateau, China显示文摘The Tibetan Plateau is home to the largest aggregate of glaciers outside the Polar Regions and is a source of fresh water to 1.4 billion people. Yet little is known about the transportation and cycling of Hg in high-elevation glacier basins on Tibetan Plateau. In this study, surface snow,glacier melting stream water and lake water samples were collected from the Qiangyong Glacier Basin. The spatiotemporal distribution and transportation of Hg from glacier to lake were investigated. Significant diurnal variations of dissolved Hg(DHg) concentrations were observed in the river water, with low concentrations in the morning(8:00 am–14:00 pm) and high concentrations in the afternoon(16:00 pm–20:00 pm). The DHg concentrations were exponentially correlated with runoff, which indicated that runoff was the dominant factor affecting DHg concentrations in the river water. Moreover, significant decreases of Hg were observed during transportation from glacier to lake. DHg adsorption onto particulates followed by the sedimentation of particulate-bound Hg(PHg) could be possible as an important Hg removal mechanism during the transportation process. Significant decreases in Hg concentrations were observed downstream of Xiao Qiangyong Lake, which indicated that the high-elevation lake system could significantly affect the distribution and transportation of Hg in the Qiangyong Glacier Basin. | Shiwei Sun | 2016 | Journal of Environmental Sciences2016，28，6： | 10 |
| 3 | Wheat genomic study for genetic improvement of traits in China显示文摘Bread wheat(Triticum aestivum L.)is a major crop that feeds 40%of the world’s population.Over the past several decades,advances in genomics have led to tremendous achievements in understanding the origin and domestication of wheat,and the genetic basis of agronomically important traits,which promote the breeding of elite varieties.In this review,we focus on progress that has been made in genomic research and genetic improvement of traits such as grain yield,end-use traits,flowering regulation,nutrient use efficiency,and biotic and abiotic stress responses,and various breeding strategies that contributed mainly by Chinese scientists.Functional genomic research in wheat is entering a new era with the availability of multiple reference wheat genome assemblies and the development of cutting-edge technologies such as precise genome editing tools,highthroughput phenotyping platforms,sequencing-based cloning strategies,high-efficiency genetic transformation systems,and speed-breeding facilities.These insights will further extend our understanding of the molecular mechanisms and regulatory networks underlying agronomic traits and facilitate the breeding process,ultimately contributing to more sustainable agriculture in China and throughout the world. | Jun Xiao Bao Liu Yingyin Yao Zifeng Guo Haiyan Jia Lingrang Kong Aimin Zhang Wujun Ma Zhongfu Ni Shengbao Xu Fei Lu Yuannian Jiao Wuyun Yang Xuelei Lin Silong Sun Zefu Lu Lifeng Gao Guangyao Zhao Shuanghe Cao Qian Chen Kunpu Zhang Mengcheng Wang Meng Wang Zhaorong Hu Weilong Guo Guoqiang Li Xin Ma Junming Li Fangpu Han Xiangdong Fu Zhengqiang Ma Daowen Wang Xueyong Zhang Hong-Qing Ling Guangmin Xia Yiping Tong Zhiyong Liu Zhonghu He Jizeng Jia Kang Chong | 2022 | Science China(Life Sciences)2022，65，9： | 9 |
| 4 | Insights into mercury in glacier snow and its incorporation into meltwater runoff based on observations in the southern Tibetan Plateau显示文摘The Tibetan Plateau(TP) is recognized as 'Water Tower of Asia'. Yet our understanding of mechanisms influencing incorporation of mercury(Hg) into freshwater in mountain glaciers on the TP remains quite limited. Extensive sampling of environmental matrices(e.g., snow/ice)were conducted on the East Rongbuk glacier on Mt. Everest and Zhadang glacier on Mt.Nyainqentanglha for Hg speciation analysis. Speciated Hg behaved quite different during snowmelt: a preferential early release of DHg(dissolved Hg) was observed at the onset of snowmelt, whereas PHg(particulate-bound Hg) and THg(total Hg) become relatively enriched in snow and released later. Small fraction of Hg in snow was lost during a snowmelt day(18.9%–34.7%) with a large proportion(58.1%–87.3%) contributed by PHg decrease, indicating that the deposited Hg is most likely retained in glacier snow/ice. Furthermore, THg were positively correlated with PHg and crustal major ions(e.g., Ca^(2+), Mg^(2+)) during snowmelt, indicating that Hg is mainly migrated with particulates. The main pathway of Hg loss during snowmelt was most probably associated with release of PHg with meltwater, which was greatly influenced by ablation intensity of snow/ice. This should be paid particular concern as Hg preserved in mountain glaciers will mostly enter aquatic ecosystem as climate warms, impacting on downstream ecosystems adversely. Obvious decrease of THg during the downstream transport from glacier was observed with a large proportion contributed by PHg decrease. The main removal mechanism of Hg was associated with sedimentation of PHg during the transport process. | Shiwei Sun Shichang Kang Junming Guo Qianggong Zhang Rukumesh Paudyal Xuejun Sun Dahe Qin | 2018 | Journal of Environmental Sciences2018，30，6： | 9 |
| 5 | Light-absorbing impurities on Keqikaer Glacier in western Tien Shan: concentrations and potential impact on albedo reduction显示文摘Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western Tien Shan, Central Asia, was measured. We found that the average concentrations of black carbon was 2,180 ng/g, with a range from 250 ng/g to more than 10,000 ng/g. The average concentrations of organic carbon and mineral dust were 1,738 ng/g and 194 μg/g, respectively. Based on simulations performed with the Snow Ice Aerosol Radiative model simulations, black carbon and dust are responsible for approximately 64% and 9%, respectively, of the albedo reduction, and are associated with instantaneous radiative forcing of 323.18 W/m2(ranging from 142.16 to 619.25 W/m2) and 24.05 W/m2(ranging from 0.15 to69.77 W/m2), respectively. For different scenarios, the albedo and radiative forcing effect of black carbon is considerably greater than that of dust. The estimated radiative forcing at Keqikaer Glacier is higher than most similar values estimated by previous studies on the Tibetan Plateau, perhaps as a result of black carbon enrichment by melt scavenging. Light-absorbing impurities deposited on Keqikaer Glacier appear to mainly originate from central Asia, Siberia, western China(including the Taklimakan Desert) and parts of South Asia in summer, and from the Middle East and Central Asia in winter.A footprint analysis indicates that a large fraction(>60%) of the black carbon contributions on Keqikaer Glacier comes from anthropogenic sources. These results provide a scientific basis for regional mitigation efforts to reduce black carbon. | YuLan Zhang ShiChang Kang Min Xu Michael Sprenger TanGuang Gao ZhiYuan Cong ChaoLiu Li JunMing Guo ZhiQiang Xu Yang Li Gang Li XiaoFei Li YaJun Liu HaiDong Han | 2017 | Research in Cold and Arid Regions2017，9，2： | 4 |
| 6 | Increased mercury pollution revealed by tree rings from the China's Tianshan Mountains显示文摘Mercury (Hg)can be transported globally by the atmospheric circulation and it accumulates and biomagnifies along food chains [1,2].Due to its threats to human health and wildlife when converted to the neurotoxin methyl mercury,variations in Hg concentration in various ecosystems were paid more attention by scientists recently.Natural processes such as geothermal activities, volcanic activities,and weathering of Hg-containing rocks,can release a mass of Hg to the environment.Anthropogenic emissions had become the main atmospheric pollution source since the Industrial Revolution.A recent study indicated that half of the Hg presented in atmosphere was sourced from human activities and about 73%total mercury was released after 1850[3].Aiming to reduce the impact of Hg to environmental and human health,UNEP (United Nations Environment Programme)passed the Minamata Convention in 2013to limit Hg emission through contro|ling technologies on air pollution. | Huhu Kang Xiaohong Liu Junming Guo Guobao Xu Guoju Wu Xiaomin Zeng Bo Wang Shichang Kang | 2018 | Science Bulletin2018，63，20： | 4 |
| 7 | Trace elements and rare earth elements in wet deposition of Lijiang,Mt.Yulong region,southeastern edge of the Tibetan Plateau显示文摘In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements(REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were collected from March to August in 2012 in an urban site of Lijiang city in the Mt. Yulong region. The concentrations of most trace elements and REEs were higher during the non-monsoon season than during the monsoon season,indicating that the lower concentrations of trace elements and REEs observed during monsoon had been influenced by the dilution effect of increased precipitation. The concentrations of trace elements in the precipitation of Lijiang city were slightly higher than those observed in remote sites of the Tibetan Plateau but much lower than those observed in the metropolises of China, indicating that the atmospheric environment of Lijiang city was less influenced by anthropogenic emissions, and, as a consequence, the air quality was still relatively good. However, the results of enrichment factor and principal component analysis revealed that some anthropogenic activities(e.g., the increasing traffic emissions from the rapid development of tourism) were most likely important contributors to trace elements, while the regional/local crustal sources rather than anthropogenic activities were the predominant contributors to the REEs in the wet deposition of Lijiang city. Our study was relevant not only for assessing the current status of the atmospheric environment in the Mt. Yulong region, but also for specific management actions to be implemented for the control of atmospheric inputs and the health of the environment for the future. | Junming Guo Shichang Kang Jie Huang Mika Sillanpaa Hewen Niu Xuejun Sun Yuanqing He Shijing Wang Lekhendra Tripathee | 2017 | Journal of Environmental Sciences2017，29，2： | 3 |
| 8 | Effect of daidzein on cell growth,cell cycle,and telomerase activity of human cervical cancer in vitro显示文摘 | Guo Junming Kang G Z Xiao Binxiu | | 0，，05： | 1 |
| 9 | Nitrogenous and carbonaceous aerosols in PM_(2.5) and TSP during pre-monsoon:Characteristics and sources in the highly polluted mountain valley显示文摘This study reports for the first time a comprehensive analysis of nitrogenous and carbona-ceous aerosols in simultaneously collected PM_(2.5) and TSP during pre-monsoon(March-May 2018)from a highly polluted urban Kathmandu Valley(KV)of the Himalayan foothills.The mean mass concentration of PM_(2.5)(129.8 μg/m^(3))was only-25%of TSP mass(558.7 μg/m^(3))indicating the dominance of coarser mode aerosols.However,the mean concentration as well as fractional contributions of water-soluble total nitrogen(WSTN)and carbonaceous species reveal their predominance in find-mode aerosols.The mean mass concentration of WSTN was 17.43±4.70 μg/m^(3)(14%)in PM_(2.5) and 24.64±8.07 μg/m^(3)(5%)in TSP.Moreover,the fractional contribution of total carbonaceous aerosols(TCA)is much higher in PM_(2.5)(~34%)than that in TSP(~20%).The relatively low OC/EC ratio in PM_(2.5)(3.03±1.47)and TSP(4.64±1.73)suggests fossil fuel combustion as the major sources of carbonaceous aerosols with contributions from secondary organic aerosols.Five-day air mass back trajectories sim-ulated with the HYSPLIT model,together with MODIS fire counts indicate the influence of local emissions as well as transported pollutants from the Indo-Gangetic Plain region to the south of the Himalayan foothills.Principal component analysis(PCA)also suggests a mixed contribution from other local anthropogenic,biomass burning,and crustal sources.Our re-sults highlight that it is necessary to control local emissions as well as regional transport while designing mitigation measures to reduce the KV's air pollution. | Hemraj Bhattarai Lekhendra Tripathee Shichang Kang Pengfei Chen Chhatra Mani Sharma Kirpa Ram Junming Guo Maheswar Rupakheti | 2022 | Journal of Environmental Sciences2022，34，5： | 1 |
| 10 | Dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction for selective glucose photoreforming with remarkable H_(2)coproduction显示文摘The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a novel dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction has been the production of lactic acid with high-yield and H_(2)with high-efficiency by selective glucose photoreforming.The optimized Zn_(0.3)Cd_(0.7)S exhibits outstanding H_(2)generation(13.64 mmol h^(-1)g^(-1)),glucose conversion(96.40%),and lactic acid yield(76.80%),over 272.80 and 19.21 times higher than that of bare ZnS(0.05 mmol h^(-1)g^(-1))and CdS(0.71 mmol h^(-1)g^(-1))in H_(2)generation,respectively.The marigold-like morphology provides abundant active sites and sufficient substrates accessibility for the photocatalyst,while the specific role of the homojunction formed by hexagonal wurtzite(WZ)and cubic zinc blende(ZB)in photoreforming biomass has been demonstrated by density functional theory(DFT)calculations.Glucose is converted to lactic acid on the WZ surface of Zn_(0.3)Cd_(0.7)S via the photoactive species·O_(2)^(-),while the H_(2)is evolved from protons(H^(+))in H_(2)O on the ZB surface of Zn_(0.3)Cd_(0.7)S.This work paves a promising road for the production of sustainable energy and products by integrating photocatalysis and biorefine. | Fuyan Kang Cai Shi Yeling Zhu Malin Eqi Junming Shi Min Teng Zhanhua Huang Chuanling Si Feng Jiang Jinguang Hu | 2023 | Journal of Energy Chemistry2023，，4： | 1 |
| 11 | Research progress on behaviors and environmental effects of mercury in the cryosphere of the Tibetan Plateau:a critical review显示文摘The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the'Third Pole',represents one of the most important cryospheric regions in the world.Mercury(Hg)is recognized as a global pollutant.Here,we summarize the current knowledge of Hg concentration levels,pools and spatio-temporal distribution in cryospheric environments(e.g.,glacier,permafrost),and its transfer and potential cycle in the TP cryospheric region.Transboundary transport of anthropogenic Hg from the surrounding heavily-polluted regions,such as South and Southeast Asia,provides significant sources of atmospheric Hg depositions onto the TP cryosphere.We concluded that the melting of the cryosphere on the TP represents an increasing source of Hg and brings a risk to the TP environment.In addition,global warming acts as an important catalyst accelerating the release of legacy Hg from the melting cryosphere,adversely impacting ecosystems and biological health.Furthermore,we emphasize on the remaining gaps and proposed issues needed to be addressed in future work,including enhancing our knowledge on some key release pathways and the related environmental effects of Hg in the cryospheric region,integrated observation and consideration of Hg distribution,migration and cycle processes at a key region,and uses of Hg isotopic technical and Hg models to improve the understanding of Hg cycling in the TP cryospheric region. | ShiWei Sun ShiChang Kang QiangGong Zhang JunMing Guo XueJun Sun | 2022 | Research in Cold and Arid Regions2022，14，1： | 1 |
| 12 | Iodine Promoted Ultralow Zn Nucleation Overpotential and Zn-Rich Cathode for Low-Cost, Fast-Production and High-Energy Density Anode-Free Zn-Iodine Batteries显示文摘The anode-free design is a promising strategy to increase the energy density of aqueous Zn metal batteries(AZMBs).However,the scarcity of Zn-rich cathodes and the rapid loss of limited Zn greatly hinder their commercial applications.To address these issues,a novel anode-free Zniodine battery(AFZIB)was designed via a simple,low-cost and scalable approach.Iodine plays bifunctional roles in improving the AFZIB overall performance:enabling high-performance Zn-rich cathode and modulating Zn deposition behavior.On the cathode side,the ZnI_(2) serves as Zn-rich cathode material.The graphene/polyvinyl pyrrolidone heterostructure was employed as an efficient host for ZnI_(2) to enhance electron conductivity and suppress the shuttle effect of iodine species.On the anode side,trace I_(3)^(−) additive in the electrolyte creates surface reconstruction on the commercial Cu foil.The in situ formed zincophilic Cu nanocluster allows ultralow-overpotential and uniform Zn deposition and superior reversibility(average coulombic efficiency>99.91% over 7,000 cycles).Based on such a configuration,AFZIB exhibits significantly increased energy density(162 Wh kg^(−1)) and durable cycle stability(63.8% capacity retention after 200 cycles)under practical application conditions.Considering the low cost and simple preparation methods of the electrode materials,this work paves the way for the practical application of AZMBs. | Yixiang Zhang Lequan Wang Qingyun Li Bo Hu Junming Kang Yuhuan Meng Zedong Zhao Hongbin Lu | 2022 | Nano-Micro Letters2022，14，12： | 1 |
| 13 | Mechanism of Preparation of Platform Compounds from Lignocellulosic Biomass Liquefaction Catalyzed by Bronsted Acid: A Review显示文摘Over the past two decades, research on transforming lignocellulosic biomass into small molecule chemicals byusing catalytic liquefaction has made great progress. Notably, in recent years it has been found the production of smallmolecule chemicals through directional liquefaction of lignocellulosic biomass. Understanding the liquefactionmechanism of lignocellulosic biomass is highly important. In this review, the liquefaction mechanism of lignocellulosicbiomass and model compounds of cellulose are described, and some problems and suggestions to address them aredescribed. | Kang GUO Qiyuan GUAN Junming XU Weihong TAN | 2019 | Journal of Bioresources and Bioproducts2019，4，4： | 1 |
| 14 | Atmospheric particle-bound mercury in the northern Indo-Gangetic Plain region:Insights into sources from mercury isotope analysis and influencing factors显示文摘Lumbini is a world heritage site located in the southern plains region of Nepal, and is regarded as a potential site for evaluating transboundary air pollution due to its proximity to the border with India. In this study, 82 aerosol samples were collected between April 2013 and July 2014 to investigate the levels of particulate-bound mercury(PBM) and the corresponding seasonality, sources, and influencing factors.The PBM concentration in total suspended particulate(TSP) matter ranged from 6.8 pg m^(-3) to351.7 pg m^(-3)(mean of 99.7 ± 92.6 pg m^(-3)), which exceeded the ranges reported for remote and rural sites worldwide. The Hg content(PBM/TSP) ranged from 68.2 ng g^(-1) to 1744.8 ng g^(-1)(mean of 446.9 ±312.7 ng g^(-1)), indicating anthropogenic enrichment. The PBM levels were higher in the dry season(i.e.,winter and the pre-monsoon period) than in the wet season(i.e., the monsoon period). In addition, the δ^(202) Hg signature indicated that waste/coal burning and traffic were the major sources of Hg in Lumbini during the pre-monsoon period. Meanwhile, precipitation occurring during photochemical processes in the atmosphere may have been responsible for the observed Δ^(199) Hg values in the aerosol samples obtained during the monsoon period. The PBM concentration was influenced mostly by the resuspension of polluted dust during dry periods and crop residue burning during the post-monsoon period. The estimated PBM deposition flux at Lumbini was 15.7 lg m^(-2) yr^(-1). This study provides a reference dataset of atmospheric PBM over a year, which can be useful for understanding the geochemical cycling of Hg in this region of limited data. | Junming Guo Lekhendra Tripathee Shichang Kang Qianggong Zhang Jie Huang Chhatra Mani Sharma Pengfei Chen Rukumesh Paudyal Dipesh Rupakheti | 2022 | Geoscience Frontiers2022，13，1： | 0 |
| 15 | Concentration,sources and wet deposition of dissolved nitrogen and organic carbon in the Northern Indo-Gangetic Plain during monsoon显示文摘Precipitation represents an important phenomenon for carbon and nitrogen deposition.Here,the concentrations and fluxes of dissolved organic carbon(DOC)and total dissolved nitrogen(TDN)with their potential sources were analyzed in wet precipitation during summer monsoon from the Northern Indo-Gangetic Plain(IGP),important but neglected area.The volume-weighted mean(VWM)concentration of DOC and TDN were 687.04 and 1210.23μg/L,respectively.Similarly,the VWM concentration of major ions were in a sequence of NH_(4)^(+)>Ca^(2+)>SO_(4)^(2-)>Na^(+)>K^(+)>NO_(3)~->Cl~->Mg^(2+)>F~->NO_(2)~-,suggesting NH_(4)^(+)and Ca^(2+)from agricultural activities and crustal dust played a vital role in precipitation chemistry.Moreover,the wet deposition flux of DOC and TDN were 9.95 and 17.06 kg/(ha year),respectively.The wet deposition flux of inorganic nitrogen species such as NH_(4)^(+)-N and NO_(3)^(-)-N were 14.31 and 0.47 kg/(ha year),respectively,demonstrating the strong influence of emission sources and precipitation volume.Source attribution from different analysis suggested the influence of biomass burning on DOC and anthropogenic activities(agriculture,animal husbandry)on nitrogenous species.The air-mass back trajectory analysis indicated the influence of air masses originating from the Bay of Bengal,which possibly carried marine and anthropogenic pollutants along with the biomass burning emissions to the sampling site.This study bridges the data gap in the less studied part of the northern IGP region and provides new information for policy makers to deal with pollution control. | Hemraj Bhattarai Lekhendra Tripathee Shichang Kang Chhatra Mani Sharma Pengfei Chen Junming Guo Prakriti Sharma Ghimire | 2021 | Journal of Environmental Sciences2021，33，4： | 0 |
| 16 | Spatial distribution and risk assessments of mercury in topsoils of Central Asia显示文摘Central Asia is one of the largest arid areas on earth,yet little is known about the concentration levels and risks of mercury(Hg)in the soils of this region.In this study,extensive sampling of topsoils(0-10 cm)from representative landscapes was carried out over Central Asia(i.e.,Tajikistan,Uzbekistan,and Kyrgyzstan).The total mercury(THg)concentrations in topsoils varied widely from 1.6 to 908.0 ng/g,with high values observed in samples collected in the capital cities and urban areas.Topsoil THg concentrations among different landscapes showed a decreasing order of urban(79.8±184.0 ng/g)>woodland(27.3±28.9 ng/g)>grassland(20.6±15.9 ng/g)>farmland(18.3±9.5 ng/g)>desert(12.3±8.0 ng/g).High THg concentrations were found in the capital cities/urban clusters,followed by a gradual decrease towards the peripheries.THg concentrations were found to be negatively correlated with the distance from the sampling sites to their nearest cities,indicating that anthropogenic emissions significantly influenced the spatial distribution of topsoil Hg.A significant correlation between THg concentrations and topsoil total organic carbon(TOC)contents was also observed,suggesting that TOC played an essential role in the spatial distribution of topsoil Hg.The assessments of pollution and potential ecological risk suggested that topsoils in highly densely-populated areas were contaminated by Hg and had higher degrees of potential ecological risks.The health risk assessment results showed that the exposure risk of topsoil Hg to children was higher than that to adults.Fortunately,there was no unacceptable human health risk of topsoil Hg.This study clarified the spatial distribution and risks of Hg in the Central Asian topsoils,offering new insight into the risk prevention and control of soil Hg. | Zhengzheng Yang Junming Guo Shiwei Sun Dingming Ni Pengfei Chen Dipesh Rupakheti Huhu Kang Sabur F Abdullaev Salamat Abdyzhapar uulu Shichang Kang | 2023 | Geoscience Frontiers2023，14，4： | 0 |
| 17 | Long-term mercury variations in tree rings of the permafrost forest,northeastern China显示文摘Permafrost is a potential mercury(Hg)pool released by thawing,which can raise the risk of Hg pollution under global warming.Tree rings are useful archives of environment-specific Hg exposure over long periods.We determined Hg concentrations in tree rings of two dominant tree species(Larix gmelinii Rupr.and Pinus sylvestris var.mongolica)at permafrost sites in northeastern China.The biweighted mean Hg concentrations ranged from 0.36 to 3.96 ng g^(-1) from 1840 to 2014.The tree-ring width had no significant influence on the Hg concentration.Larch Hg increased slightly before the 1970 s and peaked in the 1990 s.However,the pine Hg concentration increased continuously until the 1930 s,decreased rapidly until the 1970 s,then rose to a peak in the late 1980 s.The change of Hg concentrations in larch and pine revealed a time offset of 4 to 5 years,which implied possibly high mobility of Hg in pine tree rings.Higher Hg concentrations from 1920 to 1960 and subsequent decreases in isolated permafrost forests revealed the local geographical Hg cycling history.Lower Hg concentrations and faster increases in larch suggest the role of additional winter Hg loading for the evergreen pine and species-specific differences in root absorption in response to melting permafrost.Our results highlight possible geographical impacts on tree-ring Hg records,improve understanding of Hg cycles in permafrost forest,and suggest a need to sample additional species in a range of permafrost environments. | Huhu KANG Xiaohong LIU Junming GUO Qiuliang ZHANG Yabo WANG Jie HUANG Guobao XU Guoju WU Wensen GE Shichang KANG | 2022 | Science China Earth Sciences2022，65，7： | 0 |
| 18 | General approach for atomically dispersed precious metal catalysts toward hydrogen reaction显示文摘As a carbon-free energy carrier,hydrogen has become the pivot for future clean energy,while efficient hydrogen production and combustion still require precious metal-based catalysts.Single-atom catalysts(SACs)with high atomic utilization open up a desirable perspective for the scale applications of precious metals,but the general and facile preparation of various precious metal-based SACs remains challenging.Herein,a general movable printing method has been developed to synthesize various precious metal-based SACs,such as Pd,Pt,Rh,Ir,and Ru,and the features of highly dispersed single atoms with nitrogen coordination have been identified by comprehensive characterizations.More importantly,the synthesized Pt-and Ru-based SACs exhibit much higher activities than their corresponding nanoparticle counterparts for hydrogen oxidation reaction and hydrogen evolution reaction(HER).In addition,the Pd-based SAC delivers an excellent activity for photocatalytic hydrogen evolution.Especially for the superior mass activity of Ru-based SACs toward HER,density functional theory calculations confirmed that the adsorption of the hydrogen atom has a significant effect on the spin state and electronic structure of the catalysts. | Ruisong Li Daoxiong Wu Peng Rao Peilin Deng Jing Li Junming Luo Wei Huang Qi Chen Zhenye Kang Yijun Shen Xinlong Tian | 2023 | Carbon Energy2023，5，7： | 0 |
| 19 | Two-Wave Mixing in Resonant Photorefractive GaAs/AlGaAs Semi-insulating Multiple Quantum Wells显示文摘We have observed the two-wave mixing of the photorefractive GaAs/AIGaAs semiinsulating multiple quantum wells fabricated by film lift-off approach and proton implanting technique.Under the non-optimized condition,we have obtained the two-wave mixing gain larger than 180cm^(-1) at wavelength near 784nm for a field of 10kV/cm.Energy transfer is also observed when the applied field is perpendicular to the grating vector. | HU Chengyong ZHANG Zhiguo KANG Jing FENG Wei HU Qiang HUANG Qi ZHOU Junming | 1995 | Chinese Physics Letters1995，12，6： | 0 |
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