کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6335736 1620332 2016 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
UFP and BC at a mid-sized city in Po valley, Italy: Size-resolved partitioning between primary and newly formed particles
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علم هواشناسی
پیش نمایش صفحه اول مقاله
UFP and BC at a mid-sized city in Po valley, Italy: Size-resolved partitioning between primary and newly formed particles
چکیده انگلیسی
In Po valley (Northern Italy) concentrations of particulate matter (PM) often exceed air quality standards, and road traffic is reported as one of the main sources of pollution. This study investigates the size resolved particle number concentration and size distribution at one rural station, one urban station and one traffic station. The measured size-resolved particle number concentration has been reduced by means of cluster analysis to four particle size fractions (cluster 1: 7-29 nm, cluster 2: 29-95 nm, cluster 3: 95-264 nm, and cluster 4: 264-10,000 nm) based on their behavior in atmosphere according to common time patterns. The primary emissions from traffic are evaluated based on black carbon (BC) and size-resolved particle number concentration data, considering separately single size intervals and providing cluster-resolved information on primary and newly formed particle concentration. Particles directly emitted by vehicle exhaust exhibit similar numbers for the clusters 1 to 3 while newly formed particles mainly occurs in cluster 1. Furthermore, diurnal variation of directly emitted particles is found to closely follow the BC levels, while the trend of newly formed particles varies according to air temperature, solar radiation and particle pollution levels. The results release that in Po valley the variations of particle number levels do not always reflect the variation of road traffic emissions in urban areas as the large availability of anthropogenic precursors can favor summertime nucleation events with region-wide extension.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Atmospheric Environment - Volume 142, October 2016, Pages 120-131
نویسندگان
, , , , , , ,