Supplementary material to "In-depth characterization of submicron particulate matter inter-annual variations at a street canyon site in Northern Europe"

Abstract. Atmospheric aerosols play an important role in air pollution. Aerosol particle's chemical composition is highly variable depending on the season, hour of the day, day of the week, meteorology, and the location of the measurement site. Long measurement periods and high time-resolved data are required in order to achieve statistically relevant amount of data for assessing those variations and evaluate pollution episodes. In this study, we present continuous atmospheric PM1 (particulate matter

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In-depth characterization of submicron particulate matter inter-annual variations at a street canyon site in northern Europe

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-6297-2021 ◽

2021 ◽

Vol 21 (8) ◽

pp. 6297-6314

Author(s):

Luis M. F. Barreira ◽

Aku Helin ◽

Minna Aurela ◽

Kimmo Teinilä ◽

Milla Friman ◽

...

Keyword(s):

Particulate Matter ◽

Air Quality ◽

Aerosol Particle ◽

Street Canyon ◽

Particle Number ◽

Large Fraction ◽

Northern Europe ◽

Time Resolved ◽

Inorganic Species ◽

Pollution Episodes

Abstract. Atmospheric aerosols play an important role in air pollution. Aerosol particle chemical composition is highly variable depending on the season, hour of the day, day of the week, meteorology, and location of the measurement site. Long measurement periods and highly time-resolved data are required in order to achieve a statistically relevant amount of data for assessing those variations and evaluating pollution episodes. In this study, we present continuous atmospheric PM1 (particulate matter < 1 µm) concentration and composition measurements at an urban street canyon site located in Helsinki, Finland. The study was performed for 4.5 years (2015–2019) and involved highly time-resolved measurements by taking advantage of a suite of online state-of-the-art instruments such as an aerosol chemical speciation monitor (ACSM), a multi-angle absorption photometer (MAAP), a differential mobility particle sizer (DMPS), and an Aethalometer (AE). PM1 consisted mostly of organics, with mean mass concentrations of 2.89 µg m−3 (53 % of PM1) followed by inorganic species (1.56 µg m−3, 29 %) and equivalent black carbon (eBC, 0.97 µg m−3, 18 %). A trend analysis revealed a decrease in BC from fossil fuel (BCFF), organics, and nitrate over the studied years. Clear seasonal and/or diurnal variations were found for the measured atmospheric PM1 constituents. Particle number and mass size distributions over different seasons revealed the possible influence of secondary organic aerosols (SOAs) during summer and the dominance of ultrafine traffic aerosols during winter. The seasonality of measured constituents also impacted the particle's coating and absorptive properties. The investigation of pollution episodes observed at the site showed that a large fraction of aerosol particle mass was comprised of inorganic species during long-range transport, while during local episodes eBC and organics prevailed together with elevated particle number concentration. Overall, the results increased knowledge of the variability of PM1 concentration and composition in a Nordic traffic site and its implications on urban air quality. Considering the effects of PM mitigation policies in northern Europe in the last decades, the results obtained in this study may be considered illustrative of probable future air quality challenges in countries currently adopting similar environmental regulations.

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Supplementary material to "Chemical characterization of fine particulate matter emitted by peat fires in Central Kalimantan, Indonesia, during the 2015 El Niño"

10.5194/acp-2017-608-supplement ◽

2017 ◽

Author(s):

Thilina Jayarathne ◽

Chelsea E. Stockwell ◽

Ashley A. Gilbert ◽

Kaitlyn Daugherty ◽

Mark A. Cochrane ◽

...

Keyword(s):

Particulate Matter ◽

El Niño ◽

El Nino ◽

Fine Particulate Matter ◽

Chemical Characterization ◽

Central Kalimantan ◽

Fine Particulate ◽

Supplementary Material ◽

Peat Fires

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Incorporation of micro/nanoparticles of PCL with essential oil of Cymbopogon nardus in bacterial cellulose

International Journal of Advances in Medical Biotechnology - IJAMB ◽

10.25061/2595-3931/ijamb/2018.v1i2.18 ◽

2018 ◽

Vol 1 (2) ◽

pp. 37

Author(s):

Aline Krindges ◽

Vanusca Dalosto Jahno ◽

Fernando Morisso

Keyword(s):

Particle Size ◽

Particulate Matter ◽

Essential Oil ◽

Zeta Potential ◽

Bacterial Cellulose ◽

Culture Medium ◽

Static Culture ◽

Cymbopogon Nardus ◽

Cellulose Membranes

Incorporation studies of particles in different substrates with herbal assets growing. The objective of this work was the preparation and characterization of micro/nanoparticles containing cymbopogon nardus essential oil; and the incorporation of them on bacterial cellulose. For the development of the membranes was used the static culture medium and for the preparation of micro/nanoparticles was used the nanoprecipitation methodology. The incorporation of micro/nanoparticles was performed on samples of bacterial cellulose in wet and dry form. For the characterization of micro/nanoparticles were carried out analysis of SEM, zeta potential and particle size. For the verification of the incorporation of particulate matter in cellulose, analyses were conducted of SEM and FTIR. The results showed that it is possible the production and incorporation of micro/nanoparticles containing essential oil in bacterial cellulose membranes in wet form with ethanol.

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Catalytic Fluorination of Boron Compounds at a Bismuth Redox Platform

10.26434/chemrxiv.9729143 ◽

2019 ◽

Author(s):

Oriol Planas ◽

Feng Wang ◽

Markus Leutzsch ◽

Josep Cornella

Keyword(s):

Transition Metal ◽

Main Group ◽

Group Element ◽

Oxidation States ◽

Boron Compounds ◽

Main Text ◽

Main Group Element ◽

Rational Ligand Design ◽

Supplementary Material

The ability of bismuth to maneuver between different oxidation states in a catalytic redox cycle, mimicking the canonical organometallic steps associated to a transition metal, is an elusive and unprecedented approach in the field of homogeneous catalysis. Herein we present a catalytic protocol based on bismuth, a benign and sustainable main-group element, capable of performing every organometallic step in the context of oxidative fluorination of boron compounds; a territory reserved to transition metals. A rational ligand design featuring hypervalent coordination together with a mechanistic understanding of the fundamental steps, permitted a catalytic fluorination protocol based on a Bi(III)/Bi(V) redox couple, which represents a unique example where a main-group element is capable of outperforming its transition metal counterparts.<br>A main text and supplementary material have been attached as pdf files containing all the methodology, techniques and characterization of the compounds reported.<br>

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The impact of measures to reduce ambient air PM<sub>10</sub> concentrations originating from road dust, evaluated for a street canyon in Helsinki

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-11199-2019 ◽

2019 ◽

Vol 19 (17) ◽

pp. 11199-11212 ◽

Cited By ~ 1

Author(s):

Ana Stojiljkovic ◽

Mari Kauhaniemi ◽

Jaakko Kukkonen ◽

Kaarle Kupiainen ◽

Ari Karppinen ◽

...

Keyword(s):

Particulate Matter ◽

Air Quality ◽

Street Canyon ◽

Dust Emission ◽

Road Dust ◽

Ambient Air ◽

Air Quality Measurements ◽

Emission Models ◽

The Impact ◽

Quality Measurements

Abstract. We have numerically evaluated how effective selected potential measures would be for reducing the impact of road dust on ambient air particulate matter (PM10). The selected measures included a reduction of the use of studded tyres on light-duty vehicles and a reduction of the use of salt or sand for traction control. We have evaluated these measures for a street canyon located in central Helsinki for four years (2007–2009 and 2014). Air quality measurements were conducted in the street canyon for two years, 2009 and 2014. Two road dust emission models, NORTRIP (NOn-exhaust Road TRaffic Induced Particle emissions) and FORE (Forecasting Of Road dust Emissions), were applied in combination with the Operational Street Pollution Model (OSPM), a street canyon dispersion model, to compute the street increments of PM10 (i.e. the fraction of PM10 concentration originating from traffic emissions at the street level) within the street canyon. The predicted concentrations were compared with the air quality measurements. Both road dust emission models reproduced the seasonal variability of the PM10 concentrations fairly well but under-predicted the annual mean values. It was found that the largest reductions of concentrations could potentially be achieved by reducing the fraction of vehicles that use studded tyres. For instance, a 30 % decrease in the number of vehicles using studded tyres would result in an average decrease in the non-exhaust street increment of PM10 from 10 % to 22 %, depending on the model used and the year considered. Modelled contributions of traction sand and salt to the annual mean non-exhaust street increment of PM10 ranged from 4 % to 20 % for the traction sand and from 0.1 % to 4 % for the traction salt. The results presented here can be used to support the development of optimal strategies for reducing high springtime particulate matter concentrations originating from road dust.

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