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Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology

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Water Science and Engineering 2015年第2期8卷 164-173页

作者： Chao Hu Yi-hong Zhou Chun-ju Zhao Zhi-guo pan School of Water Resources and Hydropower Engineering Wuhan University College of Hydraulic and environmental Engineering China Three Gorges University Collaborative Innovation center for Geo-Hazards and Eco-environment in Three Gorges Area

Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak,cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laserscanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%e90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study.

关键词： Slope excavation Quality assessment Volume calculation Three-dimensional laser scanning technology

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Lightning Activity and Its Relation to the Intensity of Typhoons over the Northwest Pacific Ocean

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Advances in Atmospheric Sciences 2014年第3期31卷 581-592页

作者： pan Lunxiang QIE Xiushu WANG Dongfang Key Laboratory of the Middle Atmosphere and Global environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology

ABSTRACT Data from the World Wide Lightning Location Network （WWLLN） were used to analyze the lightning activity and the relationship between maximum sustained wind and lightning rate in 69 tropical cyclones over the Northwest Pacific Ocean from 2005 to 2009. The minimum lightning density was observed in the category 2 typhoon Kong-Rey （2007）, with a value of only 1.15 d-1 （100 kin）-2. The maximum lightning density occurred in the category 2 typhoon Mitag （2007）, with a value of 510.42 d-1 （100 km）-2. The average lightning density decreased with radius from the typhoon center in both weak （categories 1-3） and super （categories 4-5） typhoons. The average lightning density in the inner core of super typhoons was more than twice as large as that for weak typhoons. Both groups of typhoons showed a near-monotonic decrease in lightning density with radius. Results also showed that lightning activity was more active in typhoons that made landfall than in those that did not. The mean correlation coefficient between the accumulated flashes within a 600-kin radius and the maximum wind speed in the weak typhoons and super typhoons was 0.81 and 0.74, respectively. For more than 78% （56%） of the super （weak） typhoons, the lightning activity peaked before the maximum sustained wind speed, with the most common leading time being 30 （60） h. The results suggest that, for the Northwest Pacific Ocean, lightning activity might be used as a measurement of the intensification of typhoons.

关键词： lightning typhoon intensity WWLLN

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Stopping Transmission of COVID-19 in Public Facilities and Workplaces:Experience from China

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Biomedical and environmental Sciences 2022年第3期35卷 259-262页

作者： WANG Jiao YANG Wen Jing TANG Song pan Li Jun SHEN Jin John S.Ji WANG Xian Liang LI Li YING Bo ZHAO Kang Feng ZHANG Liu Bo WANG Lin SHI Xiao Ming China CDC Key Laboratory of environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China center for Global Health School of Public HealthNanjing Medical UniversityNanjing 211166JiangsuChina environmental Research center Duke Kunshan UniversityKunshan 215316JiangsuChina Global Health Institute&Nicholas School of the environment Duke UniversityDurhamNC 27708USA

The main transmission routes of Coronavirus Disease 2019(COVID-19)include droplet and contact *** transmission may be possible in specific circumstances and settings in which aerosol-generating procedures are performe... 详细信息

关键词： generating aerosol COV

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Effect of potential HONO sources on peroxyacetyl nitrate(pan)formation in eastern China in winter

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Journal of environmental Sciences 2020年第8期32卷 81-87页

作者： Jingwei Zhang Yitian Guo Yu Qu Yong Chen Ruipeng Yu Chaoyang Xue Rui Yang Qiang Zhang Xingang Liu Yujing Mu Jing Wang Can Ye Haihan Zhao Qiangqiang Sun Ziwen Wang Junling An State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China College of Earth Science University of Chinese Academy of SciencesBeijing 100049China College of Resources and environmental Sciences China Agricultural UniversityBeijing 100193China Research center for Eco-environmental Sciences Chinese Academy of SciencesBeijing 100085China Guangzhou Meteorological Observatory Guangzhou 511430China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijingChina Collaborative Innovation center for Regional environmental Quality BeijingChina State Key Laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China center for Excellence in Urban Atmospheric environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Land Science and Technology China Agricultural UniversityBeijing 100193China Qinghai Climate center Qinghai Meteorological BureauXiningQinghai 810001China

As an important secondary photochemical pollutant,peroxyacetyl nitrate(pan)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted *** observations in north China found unusually high concentrations of pan during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in pan *** the first time we systematically assessed the impact of potential HONO sources on pan formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of *** results showed that the potential HONO sources significantly improved the pan simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of pan near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze *** direct precursors of pan were aldehyde and methylglyoxal,and the primary precursors of pan were alkenes with C>3,xylenes,propene and *** above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting pan studies.

关键词： Nitrous acid(HONO) Peroxyacetyl nitrate(pan) WRF-Chem model Winter haze RO x cycles

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Refractory black carbon aerosols in rainwater in the summer of 2019 in Beijing:Mass concentration,size distribution and wet scavenging ratio

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Journal of environmental Sciences 2023年第10期132卷 31-42页

作者： Shandong Lei Baozhu Ge Hang Liu Jiannong Quan Danhui Xu Yuting Zhang Weijie Yao Lu Lei Yu Tian Qi Liao Xiaoyong Liu Jie Li Jinyuan Xin Yele Sun Pingqing Fu Junji Cao Zifa Wang Xiaole pan State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China National center for Climate Change Strategy and International Cooperation Ministry of Ecology and EnvironmentBeijing 100035China center for Excellence in Regional Atmospheric environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China

Black carbon(BC)aerosols in the atmosphere play a significant role in climate systems due to their strong ability to absorb solar *** lifetime of BC depends on atmospheric transport,aging and consequently on wet scavenging processes(in-cloud and below-cloud scavenging).In this study,sequential rainwater samples in eight rainfall events collected in 2 mm interval were measured by a tandem system including a single particle soot photometer(SP2)and a *** results showed that the volume-weighted average(VWA)mass concentrations of refractory black carbon(rBC)in each rainfall event varied,ranging from 10.8 to 78.9μg/*** highest rBC concentrations in the rainwater samples typically occurred in the first fraction from individual rainfall *** geometric mean median mass-equivalent diameter(MMD)decreased under precipitation,indicating that rBC with larger sizes was relatively aged and preferentially removed by wet scavenging.A positive correlation(R2=0.73)between the VWA mass concentrations of rBC in rainwater and that in ambient air suggested the important contribution of scavenging ***,the contributions of in-cloud and below-cloud scavenging were distinguished and accounted for 74%and 26%to wet scavenging,*** scavenging ratio of rBC particles was estimated to be 0.06 on *** study provides helpful information for better understanding the mechanism of rBC wet scavenging and reducing the uncertainty of numerical simulations of the climate effects of rBC.

关键词： Refractory black carbon Wet deposition Size distribution

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Comparison and analysis of mitigation ambitions of Parties’ updated Nationally Determined Contributions

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Advances in Climate Change Research 2023年第1期14卷 4-12页

作者： Hai-Lin WANG Yu-Yan WENG Xun-Zhang pan Institute of Energy Environment and EconomyTsinghua UniversityBeijing 100084China Think Tank center Tsinghua UniversityBeijing 100084China School of Economics and Management China University of PetroleumBeijing 102249China

Understanding mitigation ambitions of the Nationally Determined Contributions(NDCs)should include both the equity of supporting the Paris Agreement goals and the costs of achieving the proposed mitigation *** study presents a new framework that combines equity and economic costs to compare and analyze mitigation ambitions of Parties'updated *** representative 2℃ and 1.5℃ pathways,this framework uses multiple equity-principled allocations to derive the alignment of the updated NDCs with the Paris Agreement goals,and further applies a computable general equilibrium model to assess the economic costs of implementing the updated *** results show that global 2030 emissions may meet the selected global 2℃ pathway if all Parties achieve their most ambitious mitigation efforts,but there is still an emissions gap of 10-15 GtCO_(2) to follow the selected 1.5℃ *** the perspective of equity,the updated NDCs of the USA,the EU(including the UK in this study),and Japan lack ambition with respect to‘equal cumulative per capita emissions’under 2℃ and do not align with any equity principles under 1.5℃.The updated NDCs of China,India,Brazil and South Africa reflect their claims to‘equity’and‘common but differentiated responsibilities’.From the perspective of economic costs,the GDP and welfare losses of China,Brazil and South Africa incurred by achieving the updated NDCs are not lower than those of the three developed ***'s GDP loss is estimated at 0.43%-0.55%in 2030,which is higher than that of the USA(0.30%-0.38%)and the EU(0.25%-0.28%).This study suggests that developed Parties take the lead in further ratcheting up the NDCs and strengthen financial and technological support to developing countries so that the world could close the gap to 1.5℃.

关键词： Updated NDCs 2030 emissions Equity Economic costs Paris Agreement

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The Regularized WSM6 Microphysical Scheme and Its Validation in WRF 4D-Var

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Advances in Atmospheric Sciences 2023年第3期40卷 483-500页

作者： Sen YANG Deqin LI Liqiang CHEN Zhiquan LIU Xiang-Yu HUANG Xiao pan Institute of Atmospheric environment China Meteorological AdministrationShenyang 100166China National center for Atmospheric Research BoulderCO 80301USA Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China

A cold cloud assimilation scheme was developed that fully considers the water substances,i.e.,water vapor,cloud water,rain,ice,snow,and graupel,based on the single-moment WSM6 microphysical scheme and four-dimensional variational(4D-Var)data assimilation in the Weather Research and Forecasting data assimilation(WRFDA)*** verification of the regularized WSM6 and its tangent linearity model(TLM)and adjoint mode model(ADM)was proven *** groups of single observation and real sounding data assimilation experiments were set up to further verify the correctness of the assimilation *** results showed that the consideration of ice,snow,and graupel in the assimilation system of the 4D-Var,as opposed to their omission in the warm rain Kessler scheme,allowed the water substances to be reasonably updated,further improving the *** it can be further applied in the assimilation of observational data,radar reflectivities,and satellite radiances,the cold cloud assimilation scheme needs additional verification,including using conventional ground and sounding observations in the 4D-Var assimilation system.

关键词： 4D-Var data assimilation linearization numerical weather prediction WSM6

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“Zincophilic‑Hydrophobic”pan/PMMA Nanofiber Membrane Toward High‑Rate Dendrite‑Free Zn Anode

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Advanced Fiber Materials 2023年第6期5卷 2002-2015页

作者： Yanjie Wang Ning Li Huiyan Liu Juan Shi Yuequn Li Xukai Wu Zhuo Wang Chao Huang Kongyao Chen Dianbo Zhang Tianyu Wu Ping Li Cuixia Liu Liwei Mi Henan Key Laboratory of Functional Salt Materials Center for Advanced Materials ResearchZhongyuan University of Technology450007 ZhengzhouPeople’s Republic of China School of Energy and environment Zhongyuan University of Technology45

Uncontrollable Zn dendrites and side reactions seriously downgrade the cycling stability of the Zn anode,and restrict the commercialization of aqueous zinc ion ***,pan-based(pan,pan/PMMA)nanofiber membranes with uniform“zincophilic-hydrophobic”sites have been in-situ electrospun on Zn to effectively prevent harmful side reactions and control Zn plating/stripping *** abundant highly-negative functional groups(C≡N and C=O)of pan/PMMA have strong coordination interactions with Zn2+,which can accelerate Zn2+desolvation and increase the Zn2+migration ***,the even distribution of zincophilic sites can help create a uniform Zn deposition environment and enable horizontal Zn ***,the inherent“hydrophobicity”of the nonpolar carbon skeleton in pan/PMMA can prevent Zn corrosion and hydrogen evolution reaction(HER)side reactions,thus improving the cycling stability of the Zn *** a result,pan/PMMA@Zn symmetric cells demonstrated remarkable rate performance and long cycling stability,sustaining efficient operation for over 2000 cycles at 10 mA cm^(−2)with a low polarization voltage below 65 *** Zn anode modification strategy by in-situ constructed pan-based nanofiber membrane has the advantages of simple-preparation,one-step membrane construction,binder-free,uniform distribution of functionalized units,which not only provides a specific scheme for developing advanced Zn anode but also lays a certain research foundation for developing“separator-anode”integrated Zn-based batteries.

关键词： Zincophilic-hydrophobic Electrospun nanofiber membrane pan/PMMA Dendrite-free Zn anode High-rate performance

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Changes in cropland topsoil organic carbon with different fertilizations under long-term agro-ecosystem experiments across China's Mainland

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Science China(Life Sciences) 2010年第7期53卷 858-867页

作者： WANG ChengJi pan GenXing TIAN YouGuo LI LianQing ZHANG XuHui HAN XiaoJun Institute of Resources Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095China center of Soil and Fertilizer Quality Monitoring and Test Agricultural Ministry of ChinaBeijing 100026China

Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and *** data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of China's *** fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were *** was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice *** content increase was higher in rice paddies than in dry *** increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical *** increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus *** effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration ***,the extension of rational fertilization in China's croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.

关键词： long-term agro-ecosystem experiments fertilization croplands soil organic carbon carbon sequestration cross site analysis

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Transcriptome profiles reveal that gibberellin-related genes regulate weeping traits in crape myrtle

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Horticulture Research 2020年第1期7卷 2068-2081页

作者： Suzhen Li Tangchun Zheng Xiaokang Zhuo Zhuojiao Li Lulu Li Ping Li Like Qiu Huitang pan Jia Wang Tangren Cheng Qixiang Zhang Beijing Advanced Innovation center for Tree Breeding by Molecular Design Beijing Forestry UniversityBeijing 100083China Beijing Key Laboratory of Ornamental Plants Germplasm Innovation and Molecular Breeding National Engineering Research Center for FloricultureBeijing Laboratory of Urban and Rural Ecological EnvironmentEngineering Research Center of Landscape Environment of the Ministry of EducationKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of EducationSchool of Landscape ArchitectureBeijing Forestry UniversityBeijing 100083China

Plant architecture includes vital traits that influence and benefit crops,and economically important *** plant architectures provide natural *** ornamental plants are aesthetically appealing to *** regulatory mechanism controlling the weeping trait is poorly understood in crape *** investigate the weeping trait mechanism,transcriptional profiling of different organs in weeping and upright crape myrtle was performed based on *** and histological analyses demonstrated that endodermal cells were absent,and that new shoot phenotypes could be rescued by the GA3 treatment of weeping *** transcriptional analysis and coexpression network analysis(WGCNA)of differentially expressed genes indicated that GA synthesis and signal transduction pathways play a role in weeping *** the expression level of a negative element of GA signaling,LfiGRAS1,was reduced by virus-induced gene silencing(VIGS),new branches grew in infected plants in a negatively geotropic *** integrated analysis implied that GA had a strong influence on weeping crape myrtle by interacting with other *** study helps to elucidate the mechanism governing the weeping trait and can improve the efficiency of breeding in Lagerstroemia.

关键词： traits breeding crops

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