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The Performance of Downward Shortwave Radiation Products from Satellite and Reanalysis over the Transect of Zhongshan Station to Dome A, East Antarctica

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Advances in Atmospheric Sciences 2024年第8期41卷 1574-1588+1671-1675页

作者： Jiajia JIA Zhaoliang ZENG Wenqian ZHANG Xiangdong ZHENG yaqiang wang Minghu DING State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

The downward shortwave radiation（DSR） is an important part of the Earth's energy balance, driving Earth's system's energy, water, and carbon cycles. Due to the harsh Antarctic environment, the accuracy of DSR derived from satellite and reanalysis has not been systematically evaluated over the transect of Zhongshan station to Dome A, East Antarctica.Therefore, this study aims to evaluate DSR reanalysis products（ERA5-Land, ERA5, MERRA-2） and satellite products（CERES and ICDR） in this area. The results indicate that DSR exhibits obvious monthly and seasonal variations, with higher values in summer than in winter. The ERA5-Land（ICDR） DSR product demonstrated the highest（lowest） accuracy,as evidenced by a correlation coefficient of 0.988（0.918）, a root-mean-square error of 23.919（69.383） W m–2, a mean bias of –1.667（–28.223） W m–2and a mean absolute error of 13.37（58.99） W m–2. The RMSE values for the ERA5-Land reanalysis product at seven stations, namely Zhongshan, Panda 100, Panda 300, Panda 400, Taishan, Panda 1100, and Kunlun, were 30.938, 29.447, 34.507, 29.110, 20.339, 17.267, and 14.700 W m–2, respectively; with corresponding bias values of 9.887, –12.159, –19.181, –15.519, –8.118, 6.297, and 3.482 W m–2. Regarding seasonality, ERA5-Land, ERA5,and MERRA-2 reanalysis products demonstrate higher accuracies during spring and summer, while ICDR products are least accurate in autumn. Cloud cover, water vapor, total ozone, and severe weather are the main factors affecting DSR. The error of DSR products is greatest in coastal areas（particularly at the Zhongshan station） and decreases towards the inland areas of Antarctica.

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The Significant Contribution of Small-Sized and Spherical Aerosol Particles to the Decreasing Trend in Total Aerosol Optical Depth over Land from 2003 to 2018

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Engineering 2022年第9期16卷 82-92页

作者： Ke Gui Huizheng Che Lei Li Yu Zheng Lei Zhang Hujia Zhao Junting Zhong Wenrui Yao Yuanxin Liang yaqiang wang Xiaoye Zhang State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166China

The optical and microphysical properties of aerosols remain one of the greatest uncertainties associated with evaluating the climate forcing attributed to aerosols.Although the trends in aerosol optical depth(AOD)at global and regional scales have been widely examined,little attention has been paid to the trends in type-dependent AODs related to aerosol particle properties.Here,using the aerosol optical component dataset from the Multi-angle Imaging SpectroRadiometer(MISR)instrument,we investigate decadal-scale trends in total aerosol loading as well as AODs for five aerosol components by particle size and morphology during 2003–2018 over land.Relationships between the total AOD(TAOD)trends and type-dependent AOD changes were examined,and the relative contribution of each type-dependent AOD to the overall TAOD trends was quantified.By dividing the TAOD values into four different aerosol pollution levels(APLs)with splits at 0.15,0.40,and 0.80,we further explored the relationships between TAOD changes and interannual variations in the frequency-of-occurrences(FoOs)of these APLs.Long-term trends in FoOs in the different APLs show that there was a significant improvement in air quality between 2003 and 2018 in most land areas,except South Asia,corresponding to a shift from lightly polluted to clean conditions.However,the effects of different APLs on TAOD changes are regionally dependent and their extent of correlation varied spatially.Moreover,we observed that the annual mean TAOD has decreased by 0.47%.a^(-1)over land since 2003(P<0.05).This significant reduction was mainly attributed to the continued reduction in small-sized(<0.7 mm diameter)AOD(SAOD)(-0.74%.a^(-1))and spherical AOD(SPAOD)(-0.46%.a^(-1)).Statistical analysis shows that SAOD and SPAOD respectively accounted for 57.5%and 89.6%of the TAOD,but contributed 82.6%and 90.4%of the trend in TAOD.Our study suggests that small-sized and spherical aerosols composed of sulfate,organic matter,and black carbon play a dominant role in determining interannual variab

关键词： AOD MISR Aerosol pollution levels Aerosol type Particle size and morphology

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Temporal Variation and Source Identification of Black Carbon at Lin'an and Longfengshan Regional Background Stations in China

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Journal of Meteorological Research 2017年第6期31卷 1070-1084页

作者： Siyang CHENG yaqiang wang Xingqin AN State Key Laboratory of Severe Weather/Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081

Black carbon （BC） is a component of fine particulate matter （PM2.5）, associated with climate, weather, air quality, and people＇s health. However, studies on temporal variation of atmospheric BC concentration at background stations in China and its source area identification are lacking. In this paper, we use 2-yr BC observations from two background stations, Lin＇an （LAN） and Longfengshan （LFS）, to perform the investigation. The results show that the mean diurnal variation of BC has two significant peaks at LAN while different characteristics are found in the BC vari- ation at LFS, which are probably caused by the difference in emission source contributions. Seasonal variation of monthly BC shows double peaks at LAN but a single peak at LFS. The annual mean concentrations of BC at LAN and LFS decrease by 1.63 and 0.26 μg m 3 from 2009 to 2010, respectively. The annual background concentration of BC at LAN is twice higher than that at LFS. The major source of the LAN BC is industrial emission while the source of the LFS BC is residential emission. Based on transport climatology on a 7-day timescale, LAN and LFS stations are sensitive to surface emissions respectively in belt or approximately circular area, which are dominated by summer monsoon or colder land air flows in Northwest China. In addition, we statistically analyze the BC source regions by using BC observation and FLEXible PARTicle dispersion model （FLEXPART） simulation. In summer, the source regions of BC are distributed in the northwest and south of LAN and the southwest of LFS. Low BC concentration is closely related to air mass from the sea. In winter, the source regions of BC are concentrated in the west and south of LAN and the northeast of the threshold area of stot at LFS. The cold air mass in the northwest plays an important role in the purification of atmospheric BC. On a yearly scale, sources of BC are approximately from five provinces in the northwest/southeast of LAN and the west of LFS. These findings are helpful in reducing BC emission and

关键词： black carbon temporal variation source region atmospheric background station

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The optimal sex ratio in cooperatively breeding populations

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Chinese Science Bulletin 2014年第35期59卷 5074-5079页

作者： yaqiang wang Yaotang Li Ruiwu wang School of Mathematics and Statistics Yunnan University State Key Laboratory of Genetic Resources and Evolution EcologyConservationand Environment CenterKunming Institute of ZoologyChinese Academy of Sciences

In some cooperatively breeding species,elder siblings remain within their home ranges to assist their parents in raising their younger siblings by providing protection or food.Previous attempts to model the population sex ratios of such species have assumed that helping is cost-free and only involves benefits to parents,resulting in offspring sex ratio biases towards the helping sex.However,parents may also incur costs in maintaining helpers.We incorporated costs and benefits of helping to predict the sex ratio of offspring in a theoretical model.Our model showed that the evolutionary stable strategy(ESS)sex ratio strongly depends on three parameters:(1) the average number of helpers per female;(2) the benefits that a helper brings to its mother's offspring production(MOP);and(3) the cost-benefit ratio of helping.When one sex of elder siblings provides help,the ESS sex ratio is biased towards the helping sex if MOP costs are less than the benefits,(i.e.,the cost-benefit ratio \1).However,the ESS sex ratio becomes biased towards the non-helping sex if MOP costs exceed the benefits(i.e.,the cost-benefit ratio [1).Additionally,our model shows that the ESS sex ratio becomes biased in favor of the more helpful sex when both male and female elder siblings provide help.These results explain why sex ratios may become biased towardsthe helping sex,as well as the non-helping sex,in some species.

关键词：性别比例育种群体成本效益协作进化稳定策略模型显示 ESS MOP

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臭氧催化氧化处理焦化废水尾水的催化剂适配研究

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煤炭转化 2024年第2期47卷 67-75页

作者：马栋段超王亚强梁江朋煤炭科学技术研究院有限公司煤化工分院北京100013 煤炭资源高效开采与洁净利用国家重点实验室北京100013

为解决焦化废水尾水中有机物难降解问题,采用浸渍-煅烧法制备了负载活性金属氧化物的活性氧化铝型催化剂,通过臭氧催化氧化实验探索了载体和活性组分种类对COD去除率的影响,并对去除效率最高效的催化剂进行了表征分析。结果表明:BET分... 详细信息

为解决焦化废水尾水中有机物难降解问题,采用浸渍-煅烧法制备了负载活性金属氧化物的活性氧化铝型催化剂,通过臭氧催化氧化实验探索了载体和活性组分种类对COD去除率的影响,并对去除效率最高效的催化剂进行了表征分析。结果表明:BET分析发现Mn-Ni/γ-Al_(2)O_(3)(n_(Mn)∶n_(Ni)=2∶1)保留了γ-Al_(2)O_(3)的介孔结构,具有较大的表面积和孔体积,但负载后催化剂的比表面积和孔体积都有所降低,孔径变大;XPS和XRD分析发现锰主要以α-MnO_(2)形式存在,镍主要以复合价态存在,且二者存在强烈的相互作用;煅烧温度为450℃,煅烧时间为4 h,活性氧化铝载体催化活性最高;单组分催化剂相比于多组分催化剂,催化活性较低,其中Mn-Ni/γ-Al_(2)O_(3)的催化活性最好,60 min COD的去除率能达到43.26%,且重复使用6次后,COD的去除率仍达35.65%,催化活性仅降低17.60%,且Mn和Ni溶出量较低,表明催化剂具有良好的稳定性和重复使用性。

关键词： Mn-Ni/γ-Al_(2)O_(3) 臭氧催化氧化焦化废水尾水适配催化剂活性

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Carbide precipitates and mechanical properties of medium Mn steel joint with metal inert gas welding

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Journal of Materials Science & Technology 2021年第16期75卷 48-58页

作者： Jiang Yang Honggang Dong Yueqing Xia Peng Li Xiaohu Hao yaqiang wang Wei Wu Baosen wang School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Baosteel Central Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 200431China

Medium Mn steel was metal inert gas(MIG)welded with NiCrMo-3 and 307 Si filler wires.The effect of filler wires on the microstructure and mechanical properties of joint was investigated,and the carbide precipitates were contrastively discussed.The results revealed that the microstructure of weld metal,heat-affected zone and base metal are austenite.Obvious grain coarsening occurred in the heat-affected zone(HAZ),and the maximum grain size grew up to 160μm.In HAZ,C and Cr segregated at grain boundaries,the carbides was identified as Cr7 C3.The dispersive(Nb,Mo)C phase was also found in weld metal with NiCrMo-3 filler wire.All the welded joints failed in HAZ during tensile tests.The tensile strength of welded joint with NiCrMo-3 filler wire was 675 MPa,which is much higher than that with307 Si filler wire.In comparison to base metal,higher microhardness and lower impact toughness were obtained in HAZ for these two welded joints,which was attributed to the precipitation of Cr7 C3 phase and grain coarsening.The impact toughness around the fusion line is the worst for these two welded joints.

关键词： Medium Mn steel MIG welding Microstructure Precipitate Mechanical property

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Synergistic control of dual cross-linking strategy toward tailor-made hydrogels

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Science China Chemistry 2020年第12期63卷 1793-1798页

作者： Xueyu Dou Qingchen Cao Feifei Sun yaqiang wang Hufei wang Hong Shen Fei Yang Xing wang Decheng Wu Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Simple, efficient and accurate controllable systems for materials are becoming more essential, in response to the explosively growing demands in the fields of chemistry and material science. Herein, tailored hydrogels are explored depending on synergistic regulation of p H-responsive chemical networks with an "on/off" function and physical networks with dynamic selfoptimized arrangement. Thiol-disulfide exchange reaction endows hydrogels with controlled architectures while hydrogen bondstrengthened 2-ureido-4[1H]-pyrimidinone(UPy) moieties contributes a significant increase in mechanical strengths. The integration of that dual cross-linking(DC) network ensures the hydrogels with customized structure and enhanced mechanical property. Such controllably strategy is universally applicable and will open a new avenue to flexibly fabricate desired hybrid hydrogels with distinctive features and functions for their potential applications.

关键词： controlled hydrogels dual cross-linked network thiol-disulfide exchange hydrogen bonding synergistic regulation

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Orchestrated cellular,biochemical,and biomechanical optimizations endow platelet-rich plasma-based engineered cartilage with structural and biomechanical recovery

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Bioactive Materials 2021年第11期6卷 3824-3838页

作者： Ketao wang Ji Li Yuxing wang yaqiang wang Yuanyuan Qin Fei Yang Mingzhu Zhang Heng Zhu Zhongli Li Department of Orthopedics Chinese PLA General HospitalHaidianBeijing100853China Beijing Institute of Radiation Medicine/Beijing Institute of Basic Medical Sciences HaidianBeijing100850China Department of Foot and Ankle Beijing Tongren HospitalCapital Medical UniversityBeijing100730China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Orthopedic Surgery Zhongshan HospitalFudan UniversityShanghai200032China Department of Blood Transfusion Chinese PLA General HospitalHaidianBeijing100853China

Recently,biomaterials for cartilage regeneration has been intensively investigated.However,the development of scaffolds that capture regenerated cartilage with biomechanical and structural recovery has rarely been reported.To address this challenge,platelet-rich plasma(PRP)-based cartilage constructs with a well-orchestrated symphony of cellular,biochemical and biomechanical elements were prepared by simultaneously employing chondrogenic progenitor cells(CPCs)as a cell source,optimizing platelet concentration,and adding an enzyme-ion activator.It was shown that this triple-optimized PRP+CPC construct possessed increased biomechanical properties and suitable biochemical signals.The following in vitro study demonstrated that the triple-optimized PRP+CPC constructs generated cartilage-like tissue with higher expression levels of chondrogenic-specific markers,more deposition of cartilage-specific extracellular matrix(ECM),and greater biomechanical values than those of the other constructs.Twelve weeks after the construct was implanted in a cartilage defect in vivo,histological analysis,qPCR,and biomechanical tests collectively showed that the triple-optimized constructs yielded a more chondrocyte-like cell phenotype with a higher synthesis of Col-Ⅱand aggrecan.More importantly,the triple-optimized constructs facilitated cartilage regeneration with better biomechanical recovery than that of the other constructs.These results demonstrate the efficacy of the triple-optimization strategy and highlight the simplicity and potency of this PRP+CPC construct for cartilage regeneration.

关键词： Platelet-rich plasma Cartilage regeneration Structural recovery Biomechanical recovery

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Robust prediction of hourly PM2.5 from meteorological data using LightGBM

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National Science Review 2021年第10期8卷 115-126页

作者： Junting Zhong Xiaoye Zhang Ke Gui yaqiang wang Huizheng Che Xiaojing Shen Lei Zhang Yangmei Zhang Junying Sun Wenjie Zhang State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological Sciences School of Earth and Planetary Sciences University of Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

Retrieving historical fine particulate matter(PM2.5) data is key for evaluating the long-term impacts of PM2.5on the environment, human health and climate change. Satellite-based aerosol optical depth has been used to estimate PM2.5, but estimations have largely been undermined by massive missing values, low sampling frequency and weak predictive capability. Here, using a novel feature engineering approach to incorporate spatial effects from meteorological data, we developed a robust Light GBM model that predicts PM2.5at an unprecedented predictive capacity on hourly(R~2= 0.75), daily(R~2= 0.84), monthly(R~2= 0.88) and annual(R~2= 0.87) timescales. By taking advantage of spatial features, our model can also construct hourly gridded networks of PM2.5. This capability would be further enhanced if meteorological observations from regional stations were incorporated. Our results show that this model has great potential in reconstructing historical PM2.5datasets and real-time gridded networks at high spatial-temporal resolutions. The resulting datasets can be assimilated into models to produce long-term re-analysis that incorporates interactions between aerosols and physical processes.

关键词： PM

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The impact of meteorological changes from 2013 to 2017 on PM2.5 mass reduction in key regions in China

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Science China Earth Sciences 2019年第12期62卷 1885-1902页

作者： Xiaoye ZHANG Xiangde XU Yihui DING Yanju LIU Hengde ZHANG yaqiang wang Junting ZHONG Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China National Climate Centre China Meteorological AdministrationBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China

In 2013,China issued the"Action Plan for the Prevention and Control of Air Pollution"("Ten Statements of Atmosphere")and implemented a series of pollution reduction measures from 2013 to 2017.In key regions of China,the mass concentrations of particulate matter with aerodynamic equivalent diameters less than 2.5μm(PM2.5)have dropped significantly.However,the contributions of meteorological changes to PM2.5 reduction are largely uncertain,which has attracted particular concern from the government and the public.Here,we investigated the impact of large-scale and boundary layer(BL)meteorological conditions on aerosol pollution and estimated the contributions of meteorological changes to PM2.5 reduction based on in-depth analysis and diagnosis of various observed meteorological elements and an integrated pollution-linked meteorological index(PLAM,which is approximately and linearly related to PM mass concentration).In this study,we found that the meteorological conditions worsened in 2014 and 2015 and improved in 2016 and 2017 relative to those in 2013 in key regions in China.In 2017 relative to 2013,only^5%(approximately 13%of the total PM2.5 decline)of the 39.6%reduction in PM2.5 mass concentrations can be attributed to meteorological changes in the Beijing-Tianjin-Hebei(BTH)region,and only^7%(approximately 20%of the total PM2.5 decline)of the 34.3%reduction can be attributable to meteorological changes in the Yangtze River Delta(YRD)region.Overall,the PM2.5 reduction due to meteorological improvement is much lower than the observed PM2.5 reduction in these areas,which indicates that emission reduction during the five-year implementation of the"Ten Statements of Atmosphere"is the dominant factor in the improvement in air quality.The changes in meteorology and climate are conducive to PM2.5 reduction but do not dominate the substantial improvement in air quality.Similar to the above regions,in the Pearl River Delta(PRD)region,the impact of meteorological changes on the annual averaged PM2.5 concentration from 2013 t

关键词： Quantifying unfavorable meteorological conditions Contribution of Meteorological Conditions to PM2.5 Change Ten Statements of Atmosphere

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