Characterization of organic ambient aerosol during MIRAGE 2006 on three platforms

Abstract. Submicron atmospheric aerosol particles were collected during the Megacity Initiative: Local and Global Research Observation (MILAGRO) in March 2006 at three platforms located in the Mexico City urban area (at the Mexico City Atmospheric Monitoring System building – SIMAT), at about 60 km south-east of the metropolitan area (Altzomoni in the Cortes Pass), and on board the NCAR C130 aircraft. Organic functional group and elemental composition were measured by FTIR and XRF. The average organic mass (OM) concentration, calculated as the sum of organic functional group concentrations, was 9.9 μg m−3 at SIMAT, 6.6 μg m−3 at Altzomoni, and 5.7 μg m−3 on the C130. Aliphatic saturated C-C-H and carboxylic acid COOH groups dominated OM (more than 60%) at the ground sites. On the C130, a non-acid carbonyl C=O, carboxylic acid COOH, and amine NH2 groups were observed in concentrations above detection limit only outside the Mexico City basin. From the elemental composition of SIMAT samples, we estimated the upper bound of average contribution of biomass burning to the organic carbon (OC) as 33–39%. The average OM/OC ratio was 1.8 at SIMAT, 2.0 at Altzomoni, and 1.6–1.8 on the C130. On the aircraft, higher OM/OC ratios were measured outside of the Mexico City basin, north of the urban area, along the city outflow direction. The average carboxylic acid to aliphatic saturated ratio at SIMAT reflected a local increase of oxidized functional group concentration in aged particles.

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Characterization of organic ambient aerosol during MIRAGE 2006 on three platforms

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-6617-2009 ◽

2009 ◽

Vol 9 (2) ◽

pp. 6617-6655 ◽

Cited By ~ 6

Author(s):

S. Gilardoni ◽

L. Shang ◽

S. Takahama ◽

L. M. Russell ◽

J. D. Allan ◽

...

Keyword(s):

Carboxylic Acid ◽

Elemental Composition ◽

Urban Area ◽

Mexico City ◽

Functional Group ◽

Organic Functional Group ◽

System Building ◽

The City ◽

Average Contribution

Abstract. Submicron atmospheric aerosol particles were collected during the Megacity Initiative: Local and Global Research Observation (MILAGRO) in March 2006 at three platforms located in the Mexico City urban area (at the Mexico City Atmospheric Monitoring System building – SIMAT), at about 60 km south-west of the metropolitan area (Altzomoni in the Cortes Pass), and on board the NSF/NCAR aircraft C130. Organic functional group and elemental composition were measured by FTIR and XRF. The average organic mass (OM) concentration, calculated as the sum of organic functional group concentrations, was 9.9 μg m−3 at SIMAT, 6.6 μg m−3 at Altzomoni, and 5.7 μg m−3 on the C130. Aliphatic saturated C-C-H and carboxylic acid COOH groups dominated OM (more than 60%) at the ground sites. On the C130, a non-acid carbonyl C=O, and amine NH2 groups were observed in concentrations above detection limit only outside the Mexico City basin. From the elemental composition of SIMAT samples, we estimated the upper bound of average contribution of biomass burning to the organic carbon (OC) as 33–39%. The average OM/OC ratio was 1.8 at SIMAT, 2.0 at Altzomoni, and 1.6–1.8 on the C130. On the aircraft, higher OM/OC ratios were measured outside of the Mexico City basin, north of the urban area, along the city outflow direction. The average carboxylic acid plus non-acid carbonyl to aliphatic saturated ratio was higher at Altzomoni relative to SIMAT, reflecting a larger average contribution of carbonyl functional groups (largely in carboxylic acids) at the mountain site.

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Simulations of organic aerosol concentrations in Mexico City using the WRF-CHEM model during the MCMA-2006/MILAGRO campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-3789-2011 ◽

2011 ◽

Vol 11 (8) ◽

pp. 3789-3809 ◽

Cited By ~ 97

Author(s):

G. Li ◽

M. Zavala ◽

W. Lei ◽

A. P. Tsimpidi ◽

V. A. Karydis ◽

...

Keyword(s):

Urban Area ◽

Mexico City ◽

Aging Process ◽

Organic Aerosol ◽

Suburban Area ◽

Traditional Model ◽

Background Site ◽

Organic Components ◽

Early Afternoon ◽

The City

Abstract. Organic aerosol concentrations are simulated using the WRF-CHEM model in Mexico City during the period from 24 to 29 March in association with the MILAGRO-2006 campaign. Two approaches are employed to predict the variation and spatial distribution of the organic aerosol concentrations: (1) a traditional 2-product secondary organic aerosol (SOA) model with non-volatile primary organic aerosols (POA); (2) a non-traditional SOA model including the volatility basis-set modeling method in which primary organic components are assumed to be semi-volatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. The MCMA (Mexico City Metropolitan Area) 2006 official emission inventory is used in simulations and the POA emissions are modified and distributed by volatility based on dilution experiments for the non-traditional SOA model. The model results are compared to the Aerosol Mass Spectrometry (AMS) observations analyzed using the Positive Matrix Factorization (PMF) technique at an urban background site (T0) and a suburban background site (T1) in Mexico City. The traditional SOA model frequently underestimates the observed POA concentrations during rush hours and overestimates the observations in the rest of the time in the city. The model also substantially underestimates the observed SOA concentrations, particularly during daytime, and only produces 21% and 25% of the observed SOA mass in the suburban and urban area, respectively. The non-traditional SOA model performs well in simulating the POA variation, but still overestimates during daytime in the urban area. The SOA simulations are significantly improved in the non-traditional SOA model compared to the traditional SOA model and the SOA production is increased by more than 100% in the city. However, the underestimation during daytime is still salient in the urban area and the non-traditional model also fails to reproduce the high level of SOA concentrations in the suburban area. In the non-traditional SOA model, the aging process of primary organic components considerably decreases the OH levels in simulations and further impacts the SOA formation. If the aging process in the non-traditional model does not have feedback on the OH in the gas-phase chemistry, the SOA production is enhanced by more than 10% compared to the simulations with the OH feedback during daytime, and the gap between the simulations and observations in the urban area is around 3 μg m−3 or 20% on average during late morning and early afternoon, within the uncertainty from the AMS measurements and PMF analysis. In addition, glyoxal and methylglyoxal can contribute up to approximately 10% of the observed SOA mass in the urban area and 4% in the suburban area. Including the non-OH feedback and the contribution of glyoxal and methylglyoxal, the non-traditional SOA model can explain up to 83% of the observed SOA in the urban area, and the underestimation during late morning and early afternoon is reduced to 0.9 μg m−3 or 6% on average. Considering the uncertainties from measurements, emissions, meteorological conditions, aging of semi-volatile and intermediate volatile organic compounds, and contributions from background transport, the non-traditional SOA model is capable of closing the gap in SOA mass between measurements and models.

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Estudio de las fachadas de inmuebles protegidos del casco urbano de Cieza (Murcia) = Study of the facades of protected buildings in the urban area of Cieza (Murcia)

Anales de Edificación ◽

10.20868/ade.2018.3734 ◽

2018 ◽

Vol 4 (1) ◽

pp. 56

Author(s):

Eloisa González Ponce ◽

Nuria Rosa Roca ◽

Silvia Spairani Berrio ◽

Borja Perez Pardos

Keyword(s):

Urban Area ◽

General Condition ◽

Research Work ◽

The State ◽

Architectural Heritage ◽

Good General Condition ◽

Sustainable Materials ◽

The City

ResumenEl propósito principal de este trabajo de investigación se centra en el estudio del estado de conservación de las fachadas de 34 inmuebles pertenecientes al Catálogo de Bienes Inmuebles y Elementos Protegidos del Plan General del Ayuntamiento de Cieza (Murcia), concretamente de aquellos situados en el casco urbano, para aportar directrices que garanticen una intervención con materiales sostenibles coherente y respetuosa con el patrimonio arquitectónico de la ciudad. Evidentemente, un desarrollo correcto del estudio diagnóstico constructivo de las fachadas de inmuebles protegidos debe llevarse a cabo en 2 fases: la caracterización constructiva de la arquitectura de sus fachadas y el estudio de lesiones o estado actual que presentan las mismas. Tras analizar los 34 inmuebles se establece una metodología y un modelo sistemático para la documentación del grado de deterioro que presentan las fachadas de los inmuebles del Catálogo de la ciudad. Destacamos que los resultados de materiales propuestos en las fachadas dan unos niveles de deterioro “bajo” o “muy bajo” en el 70 % de los casos analizados, corroborándose el buen estado general de las mismas.AbstractThe main intention of this research work focus interest on the 34 building’s facade from the state of preservation belonging a Municipalities Heritage Catalogue of Cieza's Town (Murcia), it specifically those that located in the urban area from to comply with the guidelines established by sustainable materials coherent and respectful with the architectural heritage of the city. Evidently, a correct development of the diagnostic constructive study of the 34 building’s facade must be carried out in 2 phases: the constructive characterization of the architecture of his building’s facade and the study of the state of conservation or current condition that the same ones present. After analyzing 34 building’s facade methodology and a systematic model it establish for the documentation of a Municipalities Heritage Catalogue of Cieza's Town of the city. We emphasize that the results of proposed materials building’s facade give a few levels of low or very low deterioration in 70 % of the analyzed cases, there being corroborated the good general condition of the same ones.

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Simulations of organic aerosol concentrations in Mexico City using the WRF-CHEM model during the MCMA-2006/MILAGRO campaign

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-29349-2010 ◽

2010 ◽

Vol 10 (12) ◽

pp. 29349-29404 ◽

Cited By ~ 1

Author(s):

G. Li ◽

M. Zavala ◽

W. Lei ◽

A. P. Tsimpidi ◽

V. A. Karydis ◽

...

Keyword(s):

Urban Area ◽

Mexico City ◽

Aging Process ◽

Organic Aerosol ◽

Suburban Area ◽

Traditional Model ◽

Background Site ◽

Organic Components ◽

Early Afternoon ◽

The City

Abstract. Organic aerosol concentrations are simulated using the WRF-CHEM model in Mexico City during the period from 24 to 29 March in association with the MILAGRO-2006 campaign. Two approaches are employed to predict the variation and spatial distribution of the organic aerosol concentrations: (1) a traditional 2-product secondary organic aerosol (SOA) model with non-volatile primary organic aerosols (POA); (2) a non-traditional SOA model including the volatility basis-set modeling method in which primary organic components are assumed to be semi-volatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. The MCMA 2006 official emission inventory is used in simulations and the POA emissions are modified and distributed by volatility based on dilution experiments for the non-traditional SOA model. The model results are compared to the Aerosol Mass Spectrometry (AMS) observations analyzed using the Positive Matrix Factorization (PMF) technique at an urban background site (T0) and a suburban background site (T1) in Mexico City. The traditional SOA model frequently underestimates the observed POA concentrations during rush hours and overestimates the observations in the rest of the time in the city. The model also substantially underestimates the observed SOA concentrations, particularly during daytime, and only produces 21% and 25% of the observed SOA mass in the suburban and urban area, respectively. The non-traditional SOA model performs well in simulating the POA variation, but still overestimates during daytime in the urban area. The SOA simulations are significantly improved in the non-traditional SOA model compared to the traditional SOA model and the SOA production is increased by more than 100% in the city. However, the underestimation during daytime is still salient in the urban area and the non-traditional model also fails to reproduce the high level of SOA concentrations in the suburban area. In the non-traditional SOA model, the aging process of primary organic components considerably decreases the OH levels in simulations and further impacts the SOA formation. If the aging process in the non-traditional model does not have feedback on the OH in the gas-phase chemistry, the SOA production is enhanced by more than 10% compared to the simulations with the OH feedback during daytime, and the gap between the simulations and observations in the urban area is around 3 μg m−3 or 20% on average during late morning and early afternoon, within the uncertainty from the AMS measurements and PMF analysis. In addition, glyoxal and methylglyoxal can contribute up to approximately 10% of the observed SOA mass in the urban area and 4% in the suburban area. Including the non-OH feedback and the contribution of glyoxal and methylglyoxal, the non-traditional SOA model can explain up to 83% of the observed SOA in the urban area, and the underestimation during late morning and early afternoon is reduced to 0.9 μg m−3 or 6% on average. Considering the uncertainties from measurements, emissions, meteorological conditions, aging of SOA from anthropogenic VOCs, and contributions from background transport, the non-traditional SOA model is capable of closing the gap in SOA mass between measurements and models.

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Synthesis and Characterization of Cassava Shell Based Biodegradable Plastic with Kitosan Addition

Journal Of Natural Sciences And Mathematics Research ◽

10.21580/jnsmr.2017.3.1.1694 ◽

2017 ◽

Vol 3 (1) ◽

pp. 198

Author(s):

Supriyono Supriyono ◽

Hamdan Hadi Kusuma ◽

Mulyatun Mulyatun ◽

Biaunik Niski Kumila

Keyword(s):

Functional Group ◽

Mechanical Test ◽

Decomposition Process ◽

Biodegradable Plastic ◽

Synthesis And Characterization ◽

Plastic Properties ◽

Organic Functional Group ◽

Elongation Percentage ◽

Biodegradability Test

<p style="text-align: justify;">Wasted-plastic which is a hardly-decomposed material was one of the major problems of trash-recycling management in Indonesia. Replacing a common plastic with biodegradable plastic was one of the solution to reduce the amount of undecomposed-materials in the enviroment. Therefore, the aim of this resarch is to study how to synthesis cassava shell based biodegradable plastic and to analyse the effect of kitosan addition on cassava shell based biodegradable plastic properties. There are three basic characterization processes performed to analyse the sample properties, i.e mechanical test, FTIR and biodegradability test. Kitosan enhanced the mechanical and biodegradability properties of samples. The elongation-percentage decreased down to 8,57% along with the increasing the amount of kitosan concentration. FTIR data indicated the presence of O-H, N-H, C-H, C=C, NO2 and C-O organic functional group on biodegradable plastic samples. Kitosan reduce the decomposition process of samples due to its hydrophilicity. Sample with highest concentration of kitosan decomposed at the longest time up to 14 days. . ©2017 JNSMR UIN Walisongo. All rights reserved.</p>

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Жизненное состояние древесных насаждений в условиях города Актобе (Казахстан)

Ukrainian Journal of Ecology ◽

10.15421/2017_86 ◽

2017 ◽

Vol 7 (4) ◽

pp. 51-55

Author(s):

S. A. Abiev ◽

S. A. Aipeisova ◽

N. A. Utarbaeva

Keyword(s):

Urban Area ◽

Woody Plants ◽

Health State ◽

Urban Habitats ◽

Resistant Species ◽

Vital State ◽

Ulmus Laevis ◽

Urban Conditions ◽

The City ◽

Trees And Shrubs

<p>The purpose of our work is to assess the health state of woody plants growing in different habitats of the city of Aktobe. We have studied the health state of arboreal and shrubby plants growing in various urban habitats; the survey was conducted during 2016-2017 by route-visual method. We performed the analysis of species diversity, abundance and density in urban area. The assessment of health state of the trees was made according to V.A. Alekseev. From your data and literature review we established that such species as Ulmus pinnato-ramosa, Acer negundo, Populus tremula, Populus nigra, and Syringa vulgaris have strong winter resistnce in the territory of Aktobe; we registered that only their apex buds and emds of the shoots were frozen in severe winters. The medium-resistant speices include Ulmus laevis and Acer platonoides. They are less plastic and suffer from late spring and early autumn frosts. The Amorpha fruticosa, Vitis vinifera, and Parthenocissus guinguefolia could be considered as the non-resistant species, since they usually freeze up to the snow cover line. The analysis of the vital state made it possible to assess the resistance to urban conditions of the majority of trees and shrubs registered in urban habitats of Aktobe. According to the preliminary data, the origin of the plant and its winter resistance are of main importance when introducing new species to urban area.</p>

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