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Cluster analysis of urban ultrafine particles size distributions

Braga Ferreira, Marcel; Rolim Alves, Sílvia Beatriz; Silva Oliveira, Luis Felipe; Beddows, David C .S.; Harrison, Roy M.; Querol, Xavier (Atmospheric Pollution Research, 2018)

Measurements of particle size distribution was made in one location of an urban area in the period January–September/2015 in order to understand the sources and mechanisms influencing ultrafine particle (UFP) number ...
Evaluation of the potential of volcanic rock waste from southern Brazil as a natural soil fertilizer

Ramos, Claudete Gindri; Querol, Xavier; Celimar Dalmora, Adilson; De Jesus Pires, Karen Cristina; Homrich Schneider, Ivo André; Silva Oliveira, Luis Felipe; Müller Kautzmann, Rubens (Journal of Cleaner Production, 2017)

This study was developed to evaluate the chemical and mineralogical properties of acid volcanic rock waste from mining activities by measuring the availability of macronutrients and micronutrients in Milli-Q water, and in ...
Nanoparticles from construction wastes: A problem to health and the environment

L.S. Oliveira, Marcos; Izquierdo, Maria; Querol, Xavier; Lieberman, Roy N.; K. Saikia, Binoy; F.O. Silva, Luis (Universidad de la Costa, 2019-02-08)

The present study deals with the nano-mineralogy and geochemistry of ultrafine particles in construction waste from the Porto Alegre region in Southern Brazil. Uncontrolled construction waste dumps and poor management ...

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Cluster analysis of urban ultrafine particles size distributions
...
Braga Ferreira, Marcel | 2018

Measurements of particle size distribution was made in one location of an urban area in the period January–September/2015 in order to understand the sources and mechanisms influencing ultrafine particle (UFP) number concentrations (PNC2.5-250) using a Scanning Mobility Particle Sizer Spectrometer (SMPS). kmeans cluster analysis was applied to interpret the sources, temporal and spatial trends of UFP. Eight clusters were obtained. Main PSD patterns of each cluster, mean concentration of other air pollutants tracing specific sources and processes, and that of meteorological variables, as well as the hourly and seasonal frequencies of occurrence were used to support the interpretation of their origin. Thus, clusters were attributed to traffic rush hours, midday summer new particle formation, diurnal new particle formation and growth, growth of nucleated and other urban particles, urban background, regional and urban background and regional and urban background on cold nights. Many PSDs of the clusters were dominated by nucleation mode particles: midday nucleated fresh particles, photochemically induced (NPF); diurnal nucleation episodes (NPF2); growth of nucleated particles in nocturnal aging (GNPF). Origins of the clusters were related to local/regional sources (mostly traffic and biomass burning), atmospheric processes (photochemical formation and growth) and urban/regional background. Results clearly shows that traffic is a major UFP source in nucleation mode and occurred in higher concentrations in winter (08:00 to 12:00 h) during traffic rush hours, and at night. Photochemical nucleation occurred with a relatively low frequency but yielding very high PNC.

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Evaluation of the potential of volcanic rock waste from southern Brazil as a natural soil fertilizer
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Ramos, Claudete Gindri | 2017

This study was developed to evaluate the chemical and mineralogical properties of acid volcanic rock waste from mining activities by measuring the availability of macronutrients and micronutrients in Milli-Q water, and in acidic solutions to evaluate the potential use of this type of waste as natural soil fertilizers. The sample used in this work was obtained from a company of the mining district of Nova Prata, Rio Grande do Sul State, southern Brazil. Petrographic studies using conventional optical microscopy and scanning electron microscope allowed to define the mineral composition of in powder wastes as being comprised mainly by pyroxene, feldspar, and variable contents of amorphous glass in matrix. The primary oxides detected in the samples by X-ray Fluorescence were calcium oxide, silicon dioxide, aluminium oxide, iron oxide, and with concentration minor potassium oxide, and phosphorus oxide. Several important nutrients were transferred into the acidic solutions, indicating the significant potential and feasibility of these wastes to be effectively used as natural fertilizers. This study is of great relevance to the sector of mining and to agriculture in the region because it can create an alternative disposal treatment for tailings, and improve the environmental sustainability of local farms, thereby avoiding excessive chemical fertilizer consumption.

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Nanoparticles from construction wastes: A problem to health and the environment
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L.S. Oliveira, Marcos | 2019-02-08

The present study deals with the nano-mineralogy and geochemistry of ultrafine particles in construction waste from the Porto Alegre region in Southern Brazil. Uncontrolled construction waste dumps and poor management practices in formal disposal sites in the area may increase exposure risks to population. Whilst the physicochemical properties of construction wastes are well documented in the literature, the characteristics of nanoparticles in their formulations are not well known. Given that degradation of construction materials may unlock and enable further release of nano-particulates present, we focused on the <63 mm fraction to examine the geochemistry of inhalable nano-particulates that could cause adverse health impacts on local communities. A particular feature across the studied wastes are the numerous aerodynamically favourable, spherical-shaped nanoparticles of magnetite, rutile and anatase. The detected nanoparticles contained a number of elements including Al, As, Au, Ca, Cd, Co, Cr, Cu, Hg, Na, Fe, K, S, Sn, Si and. An enrichment in metals and metalloids such as As, Co, Cr, Cu, Hg, Fe, Sn or Ta in particles in the nano-scale range in relation to larger particles was observed. The presence of carbon nanotubes was also noted. The leaching tests showed that the construction wastes did not reach the limits for their disposal as hazardous waste according the European Directive. Whilst the majority of trace elements were highly immobile, the water extractability for oxyanionic-forming metalloids suggests possible migration to surface and groundwater bodies. This work seeks to bring awareness on the impacts of unsustainable construction waste management, and the relevance of improved regulations regarding their final disposal.

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Listar Artículos científicos por autor "Querol, Xavier"

Cluster analysis of urban ultrafine particles size distributions ﻿

Evaluation of the potential of volcanic rock waste from southern Brazil as a natural soil fertilizer ﻿

Nanoparticles from construction wastes: A problem to health and the environment ﻿

Envíos recientes

Cluster analysis of urban ultrafine particles size distributions

Evaluation of the potential of volcanic rock waste from southern Brazil as a natural soil fertilizer

Nanoparticles from construction wastes: A problem to health and the environment

Cluster analysis of urban ultrafine particles size distributions

Evaluation of the potential of volcanic rock waste from southern Brazil as a natural soil fertilizer

Nanoparticles from construction wastes: A problem to health and the environment