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Abstract

The composting process using sugarcane bagasse, animal manure, and urea as source of organic matter, microorganism, and nitrogen, respectively, were evaluated regarding the thermal behavior considering the maturation period: 0 (raw), 15, 22, 30, and 60 days. Thermogravimetric and differential thermal analysis curves were obtained in a synthetic air atmosphere and heating rate of 10 °C min−1 in the range of 30–600 °C. The raw compost showed 80% organic matter, which was reduced up to 58% to 60 days compost. Two main mass losses were verified, corresponding to characteristics exothermic peak in differential thermal analysis curves depending on the maturation period. The variation in organic composition was evaluated by Fourier transform infrared spectroscopy verifying the structures (lignin, cellulose, and hemicelluloses) changes with composting process, and the gas chromatography–mass spectrometry was used to identify substance soluble in hexane.

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Abstract  

Harbour activities such as loading, unloading and transport of materials may be an important source of Atmospheric Particulate Matter (APM). Depending on the materials, the type of operation and the meteorological conditions, these activities may have an impact on the levels of APM around harbour areas. The aim of this work was to characterize the emissions of dust providing from operations associated with phosphorite handling in harbours. Phosphorite is a non-detrital sedimentary rock which contains high amounts of phosphate bearing minerals and is used for the production of phosphorous based fertilizers. When handled in harbours frequently cause visual and environment impacts due to its physical and chemical characteristics. The techniques Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission were applied as sensitive analytical tools for the determination of heavy metals and rare earth elements in phosphorite and in the APM sampled in the harbour during the unloading operations. Results showed that manipulation of phosphorite during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were enriched in rare earth elements and heavy metals and were very affected by the provenience of the phosphorite.

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Abstract  

The growing concern about air quality in harbours is a result of the high impact of the operations on human health and environment. Harbour activities such loading, unloading and transport of dusty materials are important emission sources of Atmospheric particulate matter (APM). The assessment of these fugitive emissions is a difficult task because they depend on the materials, the type of operation and the meteorological scenarios. The main objectives of this work were (1) to evaluate if the techniques k0-based Instrumental neutron activation analysis (k0-INAA) and Particle induced X-ray emission (PIXE) are suitable techniques to assess fugitive emissions in harbours and (2) to estimate the impact of harbour activities on APM levels and composition. Several experimental campaigns were carried out in a Portuguese harbour, during unloading operations of fertilizer and phosphorite provided from Syria and Morocco. PM2.5 and PM2.5–10 were collected, in polycarbonate filters, by Gent samplers. The techniques k0-INAA and PIXE were applied as sensitive analytical tools to perform a complete chemical characterization of the collected samples. Results showed that manipulation of these materials during harbour operations resulted in high emissions of particles, principally from the coarse fraction. These emissions were very affected by the granulometry and nature of the handled materials. Fertilizer emissions were characterized by high concentration of Ca, P, K, Cr, Br and Zn, whereas phosphorite handling contributed principally for the increase of Ca, P and Cr levels.

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Abstract

The organic fraction of urban solid residues disposed of in sanitary landfills during the decomposition yields biogas and leachate, which are sources of pollution. Leachate is a resultant liquid from the decomposition of substances contained in solid residues and it contains in its composition organic and inorganic substances. Literature shows an increase in the use of thermoanalytical techniques to study the samples with environmental interest, this way thermogravimetry is used in this research. Thermogravimetric studies (TG curves) carried out on leachate and residues shows similarities in the thermal behavior, although presenting complex composition. Residue samples were collected from landfills, composting plants, sewage treatment stations, leachate, which after treatment, were submitted for thermal analysis. Kinetic parameters were determined using the Flynn–Wall–Ozawa method. In this case they show little divergence between the kinetic parameter that can be attributed to different decomposition reaction and presence of organic compounds in different phases of the decomposition with structures modified during degradation process and also due to experimental conditions of analysis.

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Abstract  

In 2006, elementary schools of inner-city Lisbon, Portugal were given questionnaires to identify respiratory problems. In 1,175 children aged 5–10 years, 27.7% reported rhinitis, 2.5% reported hay fever and 25.9% reported asthma symptoms. April and August were the months with higher incidence of rhinitis, with a considerable difference nonetheless (10.5% and 2.3%, respectively.). The former trends are addressed here by using meteorological data, PM2.5, and its elemental speciation. Mann-Whitney U-tests were applied to the data sets. Significantly higher values were found for humidity, K+, NH4 +, Sb and Zn in April, and for temperature, Cl, Mg2+ and Na+ in August. Commuter and heavy-duty traffic may contribute to rhinitis episodes.

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Summary  

A major concern with leaking petroleum is the environmental contamination by the toxic and water-soluble components such as benzene, toluene and xylenes (BTX). These hydrocarbons have relatively high pollution potential because of their significant toxicity. All BTX compounds are depressants to the central nervous system. Consequently, BTX are priority pollutants and their occurrence has led to the development of several physical, chemical and biological methods for their removal. The use of nuclear technology for protection and conservation of the environment, by the destruction of toxic organic compounds present in the environmental, drinking water, soils and industrial sewage has been the object of study of several authors in Brazil and in the world. The objective of this paper is to present the preliminary results of the study of contamination of the seawater by the main pollutants of the output and transport of petroleum, such as benzene, toluene and xylene, and their removal by the exposure to the ionizing radiation.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, C. Ramos, A. Marques, A. Silva, M. Freitas, M. Farinha, M. Reis, and A. Marques

Abstract  

The objective of this paper was to assess the air pollution and the main sources of Air Particulate Matter in the Setúbal urban/industrial area, Portugal. PM2.5 and PM2.5–10 were sampled in Nuclepore filters and lichens transplants were exposed during 9 months. The levels of elements in these two matrixes were measured by INAA and PIXE. A large data base was created and source apportionment was performed by using Principal Component Analysis. The results showed that the main sources of fine particles were anthropogenic and were related with traffic and local industry. There was an important contribution of natural sources, mainly for the coarse fraction, associated with the sea and the soil. Lichens characterization and mapping showed that different site-specific characteristics controlled the spatial distribution of different elements. This study showed that biomonitoring is an effective complementary method to traditional sampling systems.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Canha, M. Freitas, M. Almeida-Silva, S. Almeida, H. Dung, I. Dionísio, J. Cardoso, C. Pio, A. Caseiro, T. Verburg, and H. Wolterbeek

Abstract  

One Plus Sequential Air Sampler—Partisol was placed in a small village (Foros de Arrão) in central Portugal to collect PM10 (particles with an aerodynamic diameter below 10 μm), during the winter period for 3 months (December 2009–March 2010). Particles masses were gravimetrically determined and the filters were analyzed by instrumental neutron activation analysis to assess their chemical composition. The water-soluble ion compositions of the collected particles were determined by Ion-exchange Chromatography. Principal component analysis was applied to the data set of chemical elements and soluble ions to assess the main sources of the air pollutants. The use of both analytical techniques provided information about elemental solubility, such as for potassium, which was important to differentiate sources.

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Journal of Thermal Analysis and Calorimetry
Authors: Marisa S. Crespi, Quézia V. Martins, Sonia de Almeida, Hernane S. Barud, Marcelo Kobelnik, and Clóvis A. Ribeiro

Abstract

The increase in sugarcane production and processing in order to obtain important products such as sugar and ethanol has the negative aspect of also increasing industrial residues. The most important residues originated during processing are bagasse, hydrolyzed bagasse, filter cake, vinasse, and ash. Thermal analysis revealed that these residues have peculiar properties, such as the presence of lignocellulosic material, except in the ash. The amount of organic matter decreases during the treatment process, due to the addition of chemical products to the residues, which are responsible for some alteration in their thermal properties. Colorimetric analysis showed considerable K and P concentrations in the vinasse and filter-cake residues. EDX and infrared spectroscopy showed the presence of Si in the residues. A higher percent of Si in ash sample was also observed, as a product of the thermal decomposition, by TG, FTIR, and X-ray diffractometry.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Freitas, M. Reis, A. Marques, S. Almeida, M. Farinha, O. de Oliveira, M. Ventura, A. Pacheco, and L. Barros

Abstract  

Examples of the application of k 0 standardized instrumental neutron activation analysis (k 0 -INAA) to aerosols and biological monitors in the last 10 years at Instituto Tecnológico e Nuclear (ITN) are given. As an analytical technique, INAA, in association with the k 0 method was applied to these materials in four different projects, aiming at monitoring concentrations of heavy metals and others elements in the atmosphere in the Portuguese territory. In these studies we analysed the lichen Parmelia sulcata Taylor and olive tree bark as monitors as well as aerosol samples. For each project some representative results are presented, followed by a discussion of the application of this technique to environmental studies.

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