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Particle size distributions, PM2.5 concentrations and water- soluble inorganic ions in different public indoor environments： a case study in Jinan, China

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Frontiers of Environmental Science & Engineering 2013年第1期7卷 55-65页

作者： Can DONG Lingxiao YANG Chao YAN Qi yuAN yangchun yu Wenxing WANG Environment Research Institute Shandong University Jinan 250100 China School of Environmental Science and Engineering Shandong University Jinan 250100 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

In this study, we collected particles with aerodynamic diameter ?2.5 μm (PM2.5) from three different public indoor places (a supermarket, a commercial office, and a university dining hall) in Jinan, a medium-sized city located in northern China. Water-soluble inorganic ions of PM2.5 and particle size distributions were also measured. Both indoor and outdoor PM2.5 levels (102.3–143.8 μg·m?3 and 160.2–301.3 μg·m?3, respectively) were substantially higher than the value recommended by the World Health Organization (25 μg·m?3), and outdoor sources were found to be the major contributors to indoor pollutants. Diurnal particle number size distributions were different, while the maximum volume concentrations all appeared to be approximately 300 nm in the three indoor locations. Concentrations of indoor and outdoor PM2.5 were shown to exhibit the same variation trends for the supermarket and dining hall. For the office, PM2.5 concentrations during nighttime were observed to decrease sharply. Among others, SO 4 2?, NH 4 + and NO 3 ? were found to be the dominant water-soluble ions of both indoor and outdoor particles. Concentrations of NO 3 ? in the supermarket and office during the daytime were observed to decrease sharply, which might be attributed to the fact that the indoor temperature was much higher than the outdoor temperature. In addition, domestic activities such as cleaning, water usage, cooking, and smoking also played roles in degraded indoor air quality. However, the

关键词： indoor air quality indoor/outdoor ratios size distributions particles with aerodynamic diameter ?2.5 μm (PM2.5) water-soluble ions

Characteristics,evolution,and regional differences of biomass burning particles in the Sichuan Basin,China

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Journal of Environmental Sciences 2020年第3期32卷 35-46页

作者： Jinqi Luo Junke Zhang Xiaojuan Huang Qin Liu Bin Luo Wei Zhang Zhihan Rao yangchun yu Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225China Sichuan Environmental Monitoring Center Chengdu 610074China Shandong Academy for Environmental Planning Jinan 250101China

The Sichuan Basin has experienced serious air pollution from fine particulate matter(PM2.5) in the past few years with biomass burning has been identified as a major source of PM2.5 in this *** used single particle aerosol mass spectrometer to investigate the characteristics of biomass burning particles in three interacting cities representing different types of urban environment in the Sichuan Basin.A total of 739,794,279,610,and380,636 biomass burning particles were detected at Ya’an,Guang’an,and Chengdu,which represented 42%,69%,and 61%,respectively,of the total number of *** analyzed the chemical composition,transportation,and evolution of biomass burning *** contribution of K-elemental carbon and K-secondary inorganic particles was highest in Ya’an(36%) and Guang’an(47%),respectively,reflecting the important role of fresh biomass burning particles and long-distance transport in these two *** masses originating from different directions corresponded to different levels of PM2.5 and the contributions of polluted clusters increased significantly on polluted *** and secondary inorganic biomass burning particles increased pollution at Ya’an and Guang’an,respectively,but dominated different stages of pollution in Chengdu.K-nitrate particles were formed by photochemical reactions,whereas K-sulfate particles were formed by both photochemical and liquid-phase *** of the degree of particle aging showed that there were more fresh particles at Ya’an and more aged particles at Guang’*** results are useful in helping our understanding of the characteristics of biomass burning particles and evaluating their role in PM2.5 pollution in the Sichuan Basin.

关键词： Single particles Biomass burning particles Evolution Regional differences Sichuan basin

Size-resolved aerosol ionic composition and secondary formation at Mount Heng in South Central China

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Frontiers of Environmental Science & Engineering 2013年第6期7卷 815-826页

作者： Xinfeng WANG Wenxing WANG Likun XUE Xiaomei GAO Wei NIE yangchun yu Yang ZHOU Lingxiao YANG Qingzhu ZHANG Tao WANG Environment Research Institute Shandong University Jinan 250100 China Department of Civil and Environmental Engineering Hong Kong Polytechnic University Hong Kong China

To understand the size-resolved aerosol ionic composition and the factors influencing secondary aerosol formation in the upper boundary layer in South Central China, size-segregated aerosol samples were collected using a micro-orifice uniform deposit irnpactor （MOUDI） in spring 2009 at the summit of Mount Heng （1269 m asl）, followed by subsequent laboratory analyses of 13 inorganic and organic water-soluble ions. During non- dust-storm periods, the average PM1.8 concentration was 41.8 μg·m^-3, contributing to 55% of the PM10. Sulfates, nitrates, and ammonium, the dominant ions in the fine particles, amounted to 46.8% of the PM1.8. Compared with Mount Tai in the North China Plain, the concentrations of both fine and coarse particles and the ions contained therein were substantially lower. When the air masses from Southeast Asia prevailed, intensive biomass burning there led to elevated concentrations of sulfates, nitrates, ammonium, potassium, and chloride in the fine particles at Mount Heng. The air masses originating from the north Gobi brought heavy dust storms that resulted in the remarkable production of sulfates, ammonium, methane sulfonic acid, and oxalates in the coarse particles. Generally, the sulfates were primarily produced in the form of （NH4）2SO4 in the droplet mode via heterogeneous aqueous reactions. Only approximately one-third of the nitrates were distributed in the fine mode, and high humidity facilitated the secondary formation of fine nitrates. The heterogeneous formation of coarse nitrates and ammonium on dry alkaline dust surfaces was found to be less efficient than that on the coarse particles during non-dust-storm periods.

关键词： aerosol water-soluble ions size distributions,secondary formation dust storm Mount Heng

后2020时期临界贫困群体的识别及影响机理研究——基于重庆市3117份农户样本的实证

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西南大学学报（自然科学版） 2025年第1期47卷 134-146页

作者：蔡进冯朝晖张宇禹洋春廖和平李斌重庆工商大学公共管理学院重庆400067 重庆工商大学工商管理学院重庆400067 西南大学地理科学学院重庆400715

临界贫困群体作为巩固脱贫攻坚时期及乡村振兴中农户返贫的潜在增量,研究其内涵、识别方法和影响机理对构建农村贫困长效治理机制具有重要意义。在阐释临界贫困内涵的基础上,构建了临界贫困群体的识别指标体系,运用全排列多边形综合图... 详细信息

临界贫困群体作为巩固脱贫攻坚时期及乡村振兴中农户返贫的潜在增量,研究其内涵、识别方法和影响机理对构建农村贫困长效治理机制具有重要意义。在阐释临界贫困内涵的基础上,构建了临界贫困群体的识别指标体系,运用全排列多边形综合图示法、中位数比例法和Dagum基尼系数,基于重庆市3117份农户样本,对临界贫困群体的识别及影响机理进行了实证研究。研究结果表明:样本农户的多维临界贫困指数整体较低,且呈现正态分布特征,介于0.257和0.839之间;从3117份一般户样本中识别出330户临界贫困户,临界贫困发生率为10.59%;在15个探测指标因素中,海拔、耕地流转情况、文化程度、劳动力数量、医疗教育负担、到场镇距离、疫情灾情影响、政策满意度、政策期望值9个指标因素与样本农户临界贫困群体在不同水平下具有统计学意义。外部环境因素中区域资源禀赋匮乏、外部机会获取偏少和地方政策支撑薄弱,内部个体因素中农户个体能力较弱、内生动力不足和家庭个体水平较差是造成临界贫困的主要因素。地方政府应规范相对贫困人口识别标准和程序,构建防止返贫致贫的动态监测预警以及农村低收入人口的帮扶机制,建立分类管理、分类帮扶、分类施策机制。

关键词：后2020时期临界贫困影响机理重庆市

云南边疆少数民族地区村域多维贫困测度及空间分异研究

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农业工程学报 2019年第22期35卷 47-57页

作者：蔡进禹洋春骆东奇李涛重庆工商大学长江上游经济研究中心重庆400067 重庆工商大学旅游与国土资源学院重庆400067 重庆工商大学商务策划学院重庆400067 西南大学地理科学学院重庆400715

边疆少数民族地区的农村贫困治理一直是脱贫攻坚战略中最难啃的"硬骨头",揭示村域农村多维贫困时空分异规律,对于促进边疆少数民族地区农民脱贫增收具有重要意义。该文以云南省镇沅县为研究对象,在构建村域多维贫困测度指标体系的基础上... 详细信息

边疆少数民族地区的农村贫困治理一直是脱贫攻坚战略中最难啃的"硬骨头",揭示村域农村多维贫困时空分异规律,对于促进边疆少数民族地区农民脱贫增收具有重要意义。该文以云南省镇沅县为研究对象,在构建村域多维贫困测度指标体系的基础上,运用多维贫困测度模型、Moran指数、地理探测器模型等方法,对镇沅县109个村的多维贫困程度、空间格局以及主导因素进行研究。结果表明:镇沅县村域多维贫困程度较高,有55个村处于高贫困水平,空间格局表现为"东西高、南北次高、中心低"的结构特征,即贫困程度较高的村集中于东部的哀牢山区和西部、北部的无量山区,贫困程度较低的村主要集中于以县城为中心的恩乐镇、按板镇东部和古城镇北部地区;空间关联格局研究表明,镇沅县村域多维贫困空间上存在着显著的集聚特征,集聚的低值中心主要分布在中部恩乐镇和按板镇,集聚的高值中心主要分布在西部的振太镇;影响镇沅县村域多维贫困空间分异的主导因素包括人均耕地面积、25°坡度以上耕地面积比例、有无出村公交线路、到县政府驻地车程时间、农药使用强度、地质灾害强度、土地流转面积比例、贫困人口比例、年人均纯收入等。地方政府应该根据区域优势资源,制定合理且有针对性的扶贫策略。

关键词：村域 GIS 多维贫困空间分异少数民族地区镇沅县

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重庆市农村多维贫困空间分异及影响因素分析

农业工程学报 2018年第22期34卷 235-245页

作者：蔡进禹洋春骆东奇邱继勤重庆工商大学旅游与国土资源学院重庆400067 重庆工商大学商务策划学院重庆400067 教育部人文社会科学重点研究基地重庆工商大学长江上游经济研究中心重庆400067

为了探索区域农村多维贫困的空间分异特征及影响因素,从而有针对性地实施扶贫开发策略,促进贫困地区农民脱贫增收。该文构建农村多维贫困测度指标体系,并在此基础上运用多边形综合图示法、莫兰指数和地理探测器模型等方法对重庆市农村... 详细信息

为了探索区域农村多维贫困的空间分异特征及影响因素,从而有针对性地实施扶贫开发策略,促进贫困地区农民脱贫增收。该文构建农村多维贫困测度指标体系,并在此基础上运用多边形综合图示法、莫兰指数和地理探测器模型等方法对重庆市农村多维贫困程度、空间格局及影响因素进行了研究。研究结果表明:重庆市农村多维贫困程度较深且区域差异较大;空间分异特征表现为高贫困水平的区县主要分布在渝东北和渝东南地区,低贫困水平的区县主要分布在主城和主城外围地区;空间关联格局特征表现为农村多维贫困在空间上呈现出显著的集聚效益,各区县主要以HH型和LL型正相关空间格局为主,HH型区县主要集中在渝东北地区,LL型区县主要集中在主城地区;农村多维贫困的空间分异主要受到地形坡度、到重庆市政府驻地距离、耕地质量等因素的影响,不同区域的主导因素有所差异。

关键词：农村耕地多维贫困空间格局重庆市

西北干旱地区乡村脱贫韧性测度及空间格局研究——基于甘肃永靖县122个村的实证

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干旱区资源与环境 2024年第11期38卷 59-70页

作者：蔡进邓甜禹洋春重庆工商大学公共管理学院重庆400067 重庆工商大学工商管理学院重庆400067

西北干旱地区的乡村发展受到诸多自然和社会经济因素的影响,提升乡村脱贫韧性对于促进乡村振兴具有重要的现实意义。文中以甘肃省永靖县为研究区域,在阐释乡村脱贫韧性理论框架的基础上,运用乡村脱贫韧性测度模型、地理探测器模型等方... 详细信息

西北干旱地区的乡村发展受到诸多自然和社会经济因素的影响,提升乡村脱贫韧性对于促进乡村振兴具有重要的现实意义。文中以甘肃省永靖县为研究区域,在阐释乡村脱贫韧性理论框架的基础上,运用乡村脱贫韧性测度模型、地理探测器模型等方法对永靖县122个行政村的脱贫韧性进行测度,并深入研究其空间格局和影响因素。研究结果表明:1)永靖县122个村的脱贫韧性水平普遍较低,且各村之间差异明显,主要呈现“中部地区韧性高,东西部地区韧性低”的空间格局特点。2)各维度的脱贫韧性空间分布不均衡,均表现出一定的集聚现象,高值中心主要集中在县城附近。3)永靖县乡村脱贫韧性并非仅由单一因素决定,而是由地理资源禀赋、政策驱动与扶持、经济发展综合情况三个维度相互作用的结果。为了提升永靖县的脱贫韧性,需要综合考虑各种因素,通过政策引导、资源配置等多种手段,促进各因素之间的良性互动和协调发展。

关键词：脱贫韧性乡村振兴西北干旱地区地理探测器永靖县

秦巴山区不同类型贫困户易地搬迁意愿及影响因素研究——基于重庆418户农户调查

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中国农业资源与区划 2021年第11期42卷 121-132页

作者：蔡进邱继勤禹洋春李斌重庆工商大学公共管理学院重庆工商大学工商管理学院

[目的]通过对重庆秦巴山区贫困农户的调研,分析秦巴山区不同类型贫困农户的易地扶贫搬迁意愿及影响因素,找出影响贫困农户搬迁的关键因子,为助推脱贫攻坚提供科学决策依据。[方法]文章运用二元Logistic回归模型,选取23个指标构建影响因... 详细信息

[目的]通过对重庆秦巴山区贫困农户的调研,分析秦巴山区不同类型贫困农户的易地扶贫搬迁意愿及影响因素,找出影响贫困农户搬迁的关键因子,为助推脱贫攻坚提供科学决策依据。[方法]文章运用二元Logistic回归模型,选取23个指标构建影响因素评价指标体系,并运用主成分分析法提取13个主要因子,分析主要因子对不同类型贫困农户的易地搬迁意愿影响因素。[结果]贫困农户搬迁意愿较强,但不同类型贫困户的搬迁意愿具有明显差异,低保兜底型贫困户>非农型贫困户>兼业型贫困户>务农型贫困户;在影响因素方面,家庭人口数量、医疗教育负担、住房结构、搬迁政策认知情况是影响贫困农户搬迁意愿的共同因素;人均耕地面积、家庭年人均纯收入、耕作半径、耕地是否流转是务农型贫困户的差异性因素,年龄、非农劳动力比重、距离村干道距离是非农型贫困户的差异性因素,家庭年人均纯收入、耕地是否流转以及住房结构是兼业型贫困户的差异性因素,人均耕地面积、人均住房面积和搬迁方式满意情况是低保兜底型贫困户的差异性因素。[结论]不同类型贫困农户易地搬迁意愿及影响因素具有显著差异,政府应该在充分尊重农户意愿的基础上推进易地扶贫搬迁工作,并构建一套长效稳定增收机制。

关键词：易地搬迁贫困户影响因素秦巴山区

Effect of Rare Earths on Microstructure and Properties of Sn2.0Ag0.7CuRE Solder Alloy for Surface Mount Technology

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Journal of Rare Earths 2005年第4期23卷 I0009-I0009页

作者： Cheng Guanghui Zhang Keke Man Hua Yang Jie Liu Yamin yu yangchun School of Materials Science ＆ Engineering Henan University of Science ＆ Technology Luoyang 471003 China

A new type of lead-free solder alloy Sn2.0Ag0.7CuRE was fabricated under vacuum condition. The microstructure and properties of the material, such as tensile strength, elongation, melting range, conductance and spreading area were all investigated. Result shows that when the content of RE ≤ 0.1% （mass fraction）, RE distribute uniformly in the solder alloy, and the tensile strength and conductance of Sn2.0Ag0.7CuRE solder alloy are better than those of traditional Sn37Pb solder. Its elongation and spreading area are almost equal to those of Sn37Pb solder. When the content of RE reaches 0.5%, RE compounds can be easily found around the boundaries of grains and phases, and the tensile strength and elongation and spreading area of Sn2.0Ag0.7CuRE solder alloy all decrease sharply. Therefore, RE amount added to the Sn2.0Ag0.7CuRE solder alloy under 0.1% is proper.

关键词： SnAgCuRE solder alloy fabrication technology microstructure properties