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Climate-driven changes in drought metrics across the Yellow River Basin based on Coupled Model Intercomparison Project Phase 6

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Journal of Geographical Sciences 2024年第9期34卷 1841-1856页

作者： liu jiayuan liu Xianfeng LIANG Juan FENG Yu School of Geography and Tourist Shaanxi Normal UniversityXi'an 710119China Ningbo Institute of Digital Twin Eastern Institute for Advanced StudyNingbo 315200ZhejiangChina

Recent climate change has accelerated the global hydrological cycle, substantially affecting drought metrics such as drought duration and drought propagation;however, knowledge of drought patterns in these metrics remains limited. Here, we aimed to address the evolution and influencing factors of major drought metrics under past and future climate scenarios within the Yellow River Basin(YRB) based on Coupled Model Intercomparison Project Phase 6(CMIP6). Accordingly, we investigated the changes in drought duration for meteorological drought and agricultural drought across the YRB and identified the variability in drought propagation time from meteorological drought to agricultural drought by using a standardized precipitation/soil moisture index and run theory. Meteorological and agricultural drought duration, and propagation time, increased from 1850 to 2014, decreased significantly from 2015 to 2100 with change trends of –0.0027, –0.0197, and –0.002 month/year, respectively. Drought duration had a negative sensitivity to humidification, and agricultural drought was more sensitive than meteorological drought. Propagation time exhibited a greater sensitivity to meteorological humidification than agricultural humidification. The results also suggest that precipitation, evapotranspiration, and soil moisture are the main drivers of drought metric changes, with air temperature and crop cover exhibiting a strong indirect effect on drought metrics in the YRB. Decreased propagation time from meteorological to agricultural drought and decreased duration provide evidence for the accelerated occurrence and increased impact of drought, highlighting the importance of a more comprehensive understanding of drought metric changes under rapid climate change.

关键词： drought duration drought propagation climate change humidification Yellow River Basin CMIP6

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Identify the contribution of vehicle non-exhaust emissions:a single particle aerosol mass spectrometer test case at typical road environment

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Frontiers of Environmental Science & Engineering 2023年第5期17卷 117-128页

作者： Qijun Zhang jiayuan liu Ning Wei Congbo Song Jianfei Peng Lin Wu Hongjun Mao Tianjin Key Laboratory of Urban Transport Emission Research&State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300071China School of Geography Earth and Environment Sciences University of BirminghamBirmingham B152TTUK

A single particle aerosol mass spectrometer(SPAMS)was used to accurately quantify the contribution of vehicle non-exhaust emissions to particulate matter at typical road *** PM_(2.5),black carbon,meteorological parameters and traffic flow were recorded during the test *** daily trend for traffic flow and speed on TEDA Street showed obvious“M”and“W”characteristics.6.3 million particles were captured via the SPAMS,including 1.3 million particles with positive and negative spectral map *** Metal,High molecular Organic Carbon,Organic Carbon,Mixed Carbon,Elemental Carbon,Rich Potassium,Levo-rotation Glucose,Rich Na,SiO_(3) and other categories were *** particle number concentration measured by SPAMS showed a good linear correlation with the mass concentrations of PM_(2.5) and BC,which indicates that the particulate matter captured by the SPAMS reflects the pollution level of fine particulate ***,ECOC,OC,HM and crustal dust components were found to show high values from 7:00–9:00 AM,showing that these chemical components are directly or indirectly related to vehicle *** on the PMF model,7 major factors are *** relative contributions of each factor were determined:vehicle exhaust emission(44.8%),coal-fired source(14.5%),biomass combustion(12.2%),crustal dust(9.4%),ship emission(9.0%),tires wear(6.6%)and brake pads wear(3.5%).The results show that the contribution of vehicle non-exhaust to particulate matter at roadside environment is approximately 10.1%.Vehicle non-exhaust emissions are the focus of future research in the vehicle pollutant emission control field.

关键词： Non-exhaust emissions SPAMS PMF Roadside environment

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Cause of PM2.5 pollution during the 2016-2017 heating season in Beijing, Tianjin, and Langfang, China

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Journal of Environmental Sciences 2020年第9期32卷 201-209页

作者： Nini Pang Jian Gao Fei Che Tong Ma Su liu Yan Yang Pusheng Zhao Jie Yuan jiayuan liu Zhongjun Xu Fahe Chai Department of Environmental Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Chinese Research Academy of Environmental Sciences Beijing 100012China Qingdao Huasi Environmental Protection Technology Co. Ltd.Qingdao 266199China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Tianjin Environmental Monitoring Center Tianjin 300191China

To investigate the cause of fine particulate matter(particles with an aerodynamic diameter less than 2.5 um,PM2.5) pollution in the heating season in the North China Plain(specifically Beijing,Tianjin,and Langfang),water-soluble ions and carbonaceous components in PM2.5were simultaneously measured by online instruments with 1-hr resolution,from November 15,2016 to March 15,*** results showed extreme severity of PM2.5 pollution on a regional *** inorganic ions(SNA,i.e.,NO3-+So42+NH4+) dominated the water-soluble ions,accounting for 30%-40% of PM2.5,while the total carbon(TC,i.e.,OC+EC) contributed to 26.5%-30.1% of PM2.5 IN the three *** were mainly responsible for the increasing PM2.5 pollution compared with organic matter(OM).NO3-was the most abundant species among water-soluble ions,but SO42- played a much more important role in driving the elevated PM2.5 *** relative humidity(RH) and its precursor SO2 were the key factors affecting the formation of *** reactions dominated the formation of nitrate which was mainly limited by HNO3 in ammonia-rich *** formation and regional transport from the heavily polluted region promoted the growth of PM2.5 concentrations in the formation stage of PM2.5 pollution in Beijing and *** transport or local emissions,along with secondary formation,made great contributions to the PM2.5 pollution in the evolution stage of PM2.5 pollution in Beijing and *** favourable meteorological conditions and regional transport from a relatively clean region both favored the diffusion of pollutants in all three cities.

关键词： pollution season driving

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Brake wear-derived particles:Single-particle mass spectral signatures and real-world emissions

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Environmental Science and Ecotechnology 2023年第3期15卷 88-97页

作者： jiayuan liu Jianfei Peng Zhengyu Men Tiange Fang Jinsheng Zhang Zhuofei Du Qijun Zhang Ting Wang Lin Wu Hongjun Mao Tianjin Key Laboratory of Urban Transport Emission Research College of Environmental Science and EngineeringNankai UniversityTianjin300071China

Brake wear is an important but unregulated vehicle-related source of atmospheric particulate matter(PM).The single-particle spectral fingerprints of brake wear particles(BWPs)provide essential information for understanding their formation mechanism and atmospheric ***,we obtained the single-particle mass spectra of BWPs by combining a brake dynamometer with an online single particle aerosol mass spectrometer and quantified real-world BWP emissions through a tunnel observation in Tianjin,*** pure BWPs mainly include three distinct types of particles,namely,Bacontaining particles,mineral particles,and carbon-containing particles,accounting for 44.2%,43.4%,and 10.3%of the total BWP number concentration,*** diversified mass spectra indicate complex BWP formation pathways,such as mechanical,phase transition,and chemical ***,the mass spectra of Ba-containing particles are unique,which allows them to serve as an excellent indicator for estimating ambient BWP *** evaluating this indicator,we find that approximately 4.0%of the PM in the tunnel could be attributable to brake wear;the real-world fleet-average emission factor of 0.28 mg km1 veh1 is consistent with the estimation obtained using the receptor *** results presented herein can be used to inform assessments of the environmental and health impacts of BWPs to formulate effective emissions control policies.

关键词： Non-exhaust emission Brake wear Single-particle aerosol mass spectrometry Tunnel measurement Emission factor

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前视觉皮质层面的制像行为阐释——对巴克森德尔《注视与分神》的解析与思考

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南京艺术学院学报（美术与设计） 2024年第1期 79-85,I0011页

作者：刘珈源江苏理工学院创新设计研究院视觉与文创设计研究所江苏常州213100

巴克森德尔的《注视与分神》一文以乔治·布拉克的画作《小提琴与水罐》为分析对象,从生物学层面上对画面形式所指涉的制像行为作了独特解读。本文将以晚近的相关研究为参照物,深入分析《注视与分神》中的重要内容,并从不同方面检验核... 详细信息

巴克森德尔的《注视与分神》一文以乔治·布拉克的画作《小提琴与水罐》为分析对象,从生物学层面上对画面形式所指涉的制像行为作了独特解读。本文将以晚近的相关研究为参照物,深入分析《注视与分神》中的重要内容,并从不同方面检验核心观点的合理性、重审此种分析的局限性,进而正确认识艺术微历史研究的可行基础。

关键词：乔治·布拉克立体主义视觉特性艺术微历史

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MICROSTRUCTURE AND SOLIDIFICATION CHARACTERISTICS OF AS-CAST Ni-BASE SUPERALLOY M91

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Acta Metallurgica Sinica(English Letters) 1991年第3期4卷 199-203页

作者： ZHANG Bingda TONG Yingjie ZHANG jiayuan liu Zezhou ZHU Yaoxiao Institute of Metal Research,Academia Sinica,Shenyang,China

In comparison with conventional superalloys,no carbide but significant amount of γ+M_3B_2 and γ+γ′ eutectics were revealed to precipitate in the stable as-cast structure of Ni-base superalloy M91 which is abundant in B and minfied in *** solidification of the superalloy,the residual liquid is much less and the tendency to porousness is *** superalloy seems to be available for turbine blade and other integral cast- ings under intermediate temperature and long-term services.

关键词： superalloy microstructure solidification

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BASIC REGULARITY OF PETROGENESIS AND METALLOGENESIS OF NANLING CRUST-DERIVED TYPE GRANITOIDS

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Geotectonica et Metallogenia 1997年第Z1期21卷 27-42页

作者： liu jiayuan WANG Rongrong WU Guoquan(Guilin College of Technology, Guilin, Guangxi, China)

In the light of analysis of the internal relations among the source strata for magmatism, thegranitic magmas and the endogenic metallizations, the basic regularity of petrogenesis and metallo-genesis of Nanling crust-derived type granitoids can be generalized as follows: (1) Two suites ofsource strata for Magmatism-the Pre-Sinian and the Lower Sinianl here the unity of the old foldbasement, the source strata for magmatism and the source strata for metallization are particularlyhighlighted. (2) Multi-stage melting of source strata for magmatism resulting in the formation ofmajor ore-related granites of three different stages (the Late Jinningean stage, the Late Caledonianstage, and the Late Indosinian-Late Yanshanian stage) under the control of tw0 tectonic units(geosyncline and diwa). (3) Three endogenic meta1logenic epoches accompanying the three stagesof ore-related granitic magmatism. (4) One major metallogenic epoch characterized by concentrat-ed commercial metallizations in large scale related to the Yanshanian crust-derived type ***,this major metallogenic epoch is exactly consistent with the stage of violent diwa ac-tivity. This is by no means fortuitous, but is the unavoidable result of the development and evolu-tion of the objective geologic history.

关键词： source strata for magmatism endogenic metal crust-derived type granite

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光质交替对LED红蓝光连续光照生菜生理伤害的削减作用机制

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中国农业大学学报 2024年第10期29卷 131-138页

作者：刘文科刘家源中国农业科学院农业环境与可持续发展研究所/农业农村部设施农业节能与废弃物处理重点实验室北京100081

为探明光质交替对LED红蓝光连续光照诱导生菜生理伤害的削减作用机制,在环境可控的植物工厂中,采用水培方法和昼夜6次取样方法(明期6 h间隔取样3次,暗期2 h间隔取样3次)研究相同日光照累积量下LED红蓝光常规光照(NL,光强400μmol/(m^(2)... 详细信息

为探明光质交替对LED红蓝光连续光照诱导生菜生理伤害的削减作用机制,在环境可控的植物工厂中,采用水培方法和昼夜6次取样方法(明期6 h间隔取样3次,暗期2 h间隔取样3次)研究相同日光照累积量下LED红蓝光常规光照(NL,光强400μmol/(m^(2)·s),光周期18 h/6 h,R/B=4∶1)、连续光照(CL,光强300μmol/(m^(2)·s),光周期24 h/0 h,R/B=4∶1)和红蓝光交替连续光照(CL-A,红光320μmol/(m^(2)·s)照射18 h,蓝光240μmol/(m^(2)·s)照射6 h)对水培生菜生长、产量和昼夜自由基清除率(DPPH)及碳水化合物、活性氧和丙二醛(MDA)含量的影响。结果表明:光照处理12 d后生菜叶片产生了生理伤害并改变了植株形态。CL-A处理地上部鲜重、叶面积最高,冠幅更大,叶片伤害等级最低。按NL、CL和CL-A顺序,生菜叶片淀粉和蔗糖含量、DPPH呈现显著递增趋势,过氧化氢和MDA含量呈现先增后降趋势,而超氧阴离子含量呈现增加或先增后降趋势。光质交替削减了连续光照诱导的生菜产生的生理伤害,该研究结果为光质交替连续光照在人工光植物工厂中的应用提供了科学支撑。

关键词：生菜连续光照光质交替碳水化合物活性氧

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基于立体视觉的光度立体LED光源位置参数标定方法

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激光与光电子学进展 2022年第16期59卷 299-306页

作者：刘嘉缘王国珲西安工业大学光电工程学院陕西西安710021

针对光度立体视觉中基于镜面反射的光源位置标定法操作复杂及误差较大等问题,提出了一种基于立体视觉的LED光源位置参数标定方法。利用双目立体视觉系统依次拍摄光度立体中的LED光源,利用基于立体视觉成像矩阵的最小二乘法计算光源的空... 详细信息

针对光度立体视觉中基于镜面反射的光源位置标定法操作复杂及误差较大等问题,提出了一种基于立体视觉的LED光源位置参数标定方法。利用双目立体视觉系统依次拍摄光度立体中的LED光源,利用基于立体视觉成像矩阵的最小二乘法计算光源的空间三维坐标,通过光度立体与双目立体视觉系统中摄像机的旋转平移关系,联立得到光源位置标定系统结构参数,进而获得光度立体中LED光源相对于摄像机的空间位置关系。实验结果表明:所提方法可以有效地解决镜面反射标定法操作繁琐的问题,与基于镜面反射的方法相比,所提方法通过操作方便的立体视觉系统即可获得精度更高的LED光源位置标定参数,得到的光源对角线距离的平均绝对误差(MAE)和均方根误差(RMSE)与镜面反射方法相比有较大程度的减小。

关键词：光源标定立体视觉 LED光源位置参数光度立体

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广西河塘岩体地质地球化学特征及成矿作用

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地质与勘探 2005年第4期41卷 23-27页

作者：王蓉嵘刘家远桂林工学院桂林541004

河塘杂岩体的组成由早而晚为:早期侵入相石英闪长岩→主体侵入相花岗闪长岩→补充侵入相二长花岗岩。岩石化学体现出由基→酸的变化规律;稀土配分模式形态相似,Eu轻、中亏损,反映了杂岩体各类岩石之间成因上不可分割的内在联系。在岩体... 详细信息

河塘杂岩体的组成由早而晚为:早期侵入相石英闪长岩→主体侵入相花岗闪长岩→补充侵入相二长花岗岩。岩石化学体现出由基→酸的变化规律;稀土配分模式形态相似,Eu轻、中亏损,反映了杂岩体各类岩石之间成因上不可分割的内在联系。在岩体及接触带主要形成Au、Cu、Fe多金属矿化,表现为具有两类不同性质的成矿作用,即岩浆自源成矿作用和岩浆他源成矿作用,并共同构成一个时空上规律组合的成矿系统。

关键词：中酸性岩浆岩岩石化学地球化学成矿作用河塘岩体广西

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