Characteristics of Carbonaceous Aerosols Emitted from Peatland Fire in Riau, Sumatra, Indonesia

Biomass burning is a significant source of fine particulate matter (PM 2.5). Forest, bush, and peat fires in Kalimantan and Sumatra, Indonesia are major sources of transboundary haze pollution in Southeast Asia. However, limited data exist regarding the chemical characteristics of aerosols at sources. We conducted intensive field studies in Riau Province, Sumatra, Indonesia, during the peatland fire and non-burning seasons Ni 2012. We characterized PM carbonaceous aerosols emitted from peatland fire based on ground-based source-dominated sampling. PM 2.5 aerosols were collected with two mini-volume samplers using Teflon and quartz fiber filters. Background aerosols were also sampled during the transition period between the non-burning and fire seasons. We analyzed the carbonaceous content (organis carbon (OC) and elemental carbon (EC)) by a thermal optical reflectance utilizing the IMPROVE_A protokol and the major organic components of the aerosols by a gas chromatography/mass spectrometry. PM 2.5 aerosols emitted from peatland fire were observed in high concentrations of 7120 _ 3620 mgm and were primarily composed of OC (71.0 _ 5.11% of PM mass). Levoglucosan exhibited the highest total ion current and was present at concentrations of 464 _ 183 µg m-3. The OC/EC ratios (36.4 _ 9.08), abundances of eight thermally-derived carbon fractions, OC/Levoglucosan ratios (10.6 _ 1.96), and Levoglucosan/Mannosan ratios (10.6 _ 2.03) represent a signature profile that is inherent in peatland fire. These data will be useful in identifying contributions from single bor multiple species in atmospheric aerosol samples collected from peatland fires

Chemical composition of PM 2.5 particles in Salamanca, Guanajuato Mexico: Source apportionment with receptor models

Laboratorio de Análisis AmbientalThe National Institute of Ecology, through Management General for Environmental Research and Training (DGCENICA) carried out a sampling campaign where a total of 21 elements were determined in 140PM 2.5 samples from one sampling site located in the city of Salamanca, Guanajuato-Mexico between November 2006 and November 2007. The annual average PM 2.5 concentration was 45μg/m 3 almost three times the Mexican Annual standard for PM 2.5. Mineral, organic and elemental carbon were the most important components present in particles PM 2.5. Two advanced receptor models, UNMIX and positive matrix factorization (PMF) were used for PM 2.5 source identification. Four and six sources were identified by UNMIX and PMF, respectively, from a combined dataset including 15 chemical species. Source categories were determined based on both, component abundances in the source profiles, and their temporal characteristics. Overall, different sources were identified as the major contributors: heavy fuels combustion, traditional brick production-agricultural burning, crustal, road traffic and secondary organic aerosols.El Instituto Nacional de Ecología, a través de la Gerencia General de Investigación y Capacitación Ambiental (DGCENICA) realizó una campaña de muestreo donde se determinaron un total de 21 elementos en 140PM 2.5 muestras de un sitio de muestreo ubicado en la ciudad de Salamanca, Guanajuato-México entre noviembre 2006 y noviembre de 2007. La concentración promedio anual de PM 2.5 fue de 45μg / m 3 casi tres veces el estándar anual mexicano para PM 2.5. El carbono mineral, orgánico y elemental fueron los componentes más importantes presentes en las partículas PM 2.5. Se utilizaron dos modelos de receptores avanzados, UNMIX y factorización de matriz positiva (PMF) para la identificación de la fuente de PM 2,5. La UNMIX y el PMF identificaron cuatro y seis fuentes, respectivamente, a partir de un conjunto de datos combinado que incluía 15 especies químicas. Las categorías de fuentes se determinaron con base tanto en la abundancia de componentes en los perfiles de fuentes como en sus características temporales. En general, se identificaron diferentes fuentes como los principales contribuyentes: combustión de combustibles pesados, producción tradicional de ladrillos, quema agrícola, corteza, tráfico rodado y aerosoles orgánicos secundarios.O Instituto Nacional de Ecologia, por meio da Gerência Geral de Pesquisa e Treinamento Ambiental (DGCENICA) realizou uma campanha de amostragem onde um total de 21 elementos foram determinados em 140 PM 2,5 amostras de um local de amostragem localizado na cidade de Salamanca, Guanajuato-México, entre novembro 2006 e novembro de 2007. A concentração média anual de PM 2.5 foi de 45μg / m 3, quase três vezes o padrão anual mexicano para PM 2.5. Carbono mineral, orgânico e elementar foram os componentes mais importantes presentes nas partículas PM 2,5. Dois modelos avançados de receptor, UNMIX e fatoração de matriz positiva (PMF), foram usados ​​para a identificação da fonte de PM 2.5. Quatro e seis fontes foram identificadas pela UNMIX e PMF, respectivamente, a partir de um conjunto de dados combinado incluindo 15 espécies químicas. As categorias de origem foram determinadas com base nas abundâncias de componentes nos perfis de origem e em suas características temporais. No geral, diferentes fontes foram identificadas como os principais contribuintes: combustão de combustíveis pesados, produção tradicional de tijolos - queima agrícola, crustal, tráfego rodoviário e aerossóis orgânicos secundários.Universidad Nacional, Costa RicaInstituto Nacional de Ecología, MéxicoOsaka Prefecture University, JapanEscuela de Ciencias Ambientale

A Comparative Study of Urban Air Quality in Megacities in Mexico and Japan: Based on Japan-Mexico Joint Research Project on Formation Mechanism of Ozone, VOCs and PM2.5, and Proposal of Countermeasure Scenario

Photochemical ozone and black carbon are key substances both for regional air pollution and global climate change. These two pollutants are so-called SLCPs (Short-Lived Climate Pollutants). International comparison studies among megacities with widely different conditions are effective in clarifying the formation mechanisms of SLCPs. A comparison study in megacity areas of Japan and Mexico mainly focusing on ozone, VOCs (volatile organic compounds) and PM2.5 was conducted based on air pollution trend analysis and field measurements including vertical soundings of ozone and meteorological parameters. In this study, co-beneficial countermeasure scenarios based upon the obtained scientific data has been proposed. Photochemical ozone, EC (elemental carbon; a major SLCP), and NOx (nitrogen oxides) and VOCs (NOx and VOCs are implicit SLCPs) need to be controlled to improve the regional and global atmospher ic environment. In Japan, countermeasures including the whole Asian area will be necessary because there is considerable contribution from trans-boundary air pollution. In Mexico, regulation of VOCs including energy shift and diesel exhaust gas control will be effective. These findings will be utilized to formulate and/or evaluate ProAire (Program for Air Quality Improvement) for the three studied megacity areas of Mexico

Characteristics of carbonaceous aerosols emitted from peatland fire in Riau, Sumatra, Indonesia

Biomass burning is a significant source of fine particulate matter (PM₂.₅). Forest, bush, and peat fires in Kalimantan and Sumatra, Indonesia are major sources of transboundary haze pollution in Southeast Asia. However, limited data exist regarding the chemical characteristics of aerosols at sources. We conducted intensive field studies in Riau Province, Sumatra, Indonesia, during the peatland fire and non-burning seasons in 2012. We characterized PM₂.₅ carbonaceous aerosols emitted from peatland fire based on ground-based source-dominated sampling. PM₂.₅ aerosols were collected with two mini-volume samplers using Teflon and quartz fiber filters. Background aerosols were also sampled during the transition period between the non-burning and fire seasons. We analyzed the carbonaceous content (organic carbon (OC) and elemental carbon (EC)) by a thermal optical reflectance utilizing the IMPROVE_A protocol and the major organic components of the aerosols by a gas chromatography/mass spectrometry. PM₂.₅ aerosols emitted from peatland fire were observed in high concentrations of 7120 ± 3620 μg m⁻³ and were primarily composed of OC (71.0 ± 5.11% of PM2.5 mass). Levoglucosan exhibited the highest total ion current and was present at concentrations of 464 ± 183 μg m⁻³. The OC/EC ratios (36.4 ± 9.08), abundances of eight thermally-derived carbon fractions, OC/Levoglucosan ratios (10.6 ± 1.96), and Levoglucosan/Mannosan ratios (10.6 ± 2.03) represent a signature profile that is inherent in peatland fire. These data will be useful in identifying contributions from single or multiple species in atmospheric aerosol samples collected from peatland fires

A Highly Active Biohybrid Catalyst for Olefin Metathesis in Water: Impact of a Hydrophobic Cavity in a β-Barrel Protein

A series of Grubbs–Hoveyda type catalyst precursors for olefin metathesis containing a maleimide moiety in the backbone of the NHC ligand was covalently incorporated in the cavity of the β-barrel protein nitrobindin. By using two protein mutants with different cavity sizes and choosing the suitable spacer length, an artificial metalloenzyme for olefin metathesis reactions in water in the absence of any organic cosolvents was obtained. High efficiencies reaching TON > 9000 in the ROMP of a water-soluble 7-oxanorbornene derivative and TON > 100 in ring-closing metathesis (RCM) of 4,4-bis­(hydroxymethyl)-1,6-heptadiene in water under relatively mild conditions (pH 6, <i>T</i> = 25–40 °C) were observed