Air pollutants

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A combined analysis of the short-term effects of photochemical air pollutants on mortality within the EMECAM project.

A combined analysis of the short-term effects of photochemical air pollutants on mortality within the EMECAM project.

health not only to particles and sulfur dioxide but also to photochemical air pollutants (nitrogen dioxide and ozone). The effects are usually small, leading to some inconsistencies in the results of the studies. Furthermore, the different methodologic approaches of the studies used has made it difficult to derive generic conclusions. We provide here a quantitative summary of the short-term effects of photochemical air pollutants on mortality in seven Spanish cities involved in the EME- CAM project, using generalized additive models from analyses of single and multiple pollutants. Nitrogen dioxide and ozone data were provided by seven EMECAM cities (Barcelona, Gijón, Huelva, Madrid, Oviedo, Seville, and Valencia). Mortality indicators included daily total mortal- ity from all causes excluding external causes, daily cardiovascular mortality, and daily respiratory mortality. Individual estimates, obtained from city-specific generalized additive Poisson autore- gressive models, were combined by means of fixed effects models and, if significant heterogeneity among local estimates was found, also by random effects models. Significant positive associations were found between daily mortality (all causes and cardiovascular) and NO 2 , once the rest of air

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TítuloComparison of three pilot plants filled with organic materials for the treatment of air pollutants from a composting plant

TítuloComparison of three pilot plants filled with organic materials for the treatment of air pollutants from a composting plant

At the same time, air samples had been collected in Tedlar® bags with a Teflon® coated pump. Then odours units (O.U.) determination had been done with a dynamic olfactometer (Model Odile, Odotech Inc.) according to the European Standard NF EN13725. Relative humidity (%) and Pressure Drop (mbar) in filters was measured by appropriate probe and sensor.

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Mapping recession risk for cultural heritage stone in Mexico City due to dry and wet deposition of urban air pollutants

Mapping recession risk for cultural heritage stone in Mexico City due to dry and wet deposition of urban air pollutants

2006). It is worth mentioning that this region is still influenced by major anthropogenic sources such as the Tula industrial complex, located north of the MCMA. The MCMA is also affected by natural sources, such as the Popocatépetl volcano east of the urban area, which produces emissions that occasion- ally affect the urban area (Garda-Escalante, 2008; De Foy et al., 2009a, b). Acid rain records for the MCMA indicate relatively high acidity in the 1990s for the western portion of the region, with a gradient toward neutral values in the east. Such conditions have changed over time, and in 2007 only a small area southwest of the city maintained such acidity. The reduced acidity tended toward neutrality for the areas north and northeast of the MCMA (SMA, 2008). Due to its geographic position, the Valley of Mexico has a rainy season between June and Sep- tember; thus, the lowest yearly pollution levels were recorded during these months. The dry season yields the highest concentrations of SO 2 and other pollutants

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Air pollution: health effects

Air pollution: health effects

Background: Air contamination happens when unsafe or inordinate amounts of substances including gases, particles, and organic atoms are brought into Earth's climate. Objective: This review article defines air pollution, describes the types of pollutants, enumerates the various causative factors, enumerates the ways it impacts human health and suggests preventive measures to reduce the impact of air pollution on human health. Methods: Literature was studied extensively and effects of air pollution on human health have been described. Results and Conclusion: Air pollution has tremendous effects on human health in the form of respiratory diseases and aggravations in the form of asthma and lung cancer, cardiovascular dysfunctions, and malignant growth. An affiliation has been found to exist between male infertility and air pollution and a relationship has been established between air contamination and higher danger of immune dysfunction, neuroinflammation, neurobehavioral hyperactivity, crime, age-unseemly behaviours, Alzheimer's and Parkinson's disease. Traffic-related air pollutants have been found to affect skin aging and cause pigmented spots on the face. An association exists between air pollution and irritation of the eyes, dry eye syndrome, risk for retinopathy and adverse ocular outcomes. Chronic exposure to air pollutants during pregnancy has been associated with adverse effects on the developing foetus in the form of low birth weight and still birth. Air contamination has been seen as a significant supporter of the expanded predominance of allergic diseases in children.

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Caracterización de las concentraciones en aire de bioaerosoles cultivables y contables en sistemas de ventilación mecánica de edificaciones administrativas en la ciudad de Bogotá en el periodo 2012 2013

Caracterización de las concentraciones en aire de bioaerosoles cultivables y contables en sistemas de ventilación mecánica de edificaciones administrativas en la ciudad de Bogotá en el periodo 2012 2013

The air pollutants, i.e. bioaerosols, are not only transferred by air but are remaining on it during long periods of time. This last fact increases the risk to present any related pathology with the pollutants. The pathologies can be typified in different ways depending on the individual characteristics of the inhabitants of the building. These pathologies can go from mild irritation of the respiratory system to severe diseases. Therefore it is of high priority the monitoring of the indoor air quality in the edification as well as a proper collaboration between the people working on the occupational health and environmental management systems with the committees in charge of the design and adequation of the architecture of the buildings. This monitoring and team work will ensure an appropriate operation and maintenance of the buildings, specially of the mechanical ventilation systems, taking into account the special proceedings to be sure to keep an indoor air quality in the building and in consequence a low biological risk for the inhabitants due to the pollutants. Finally the proper management of the air monitoring will prevent the building to be classified in the syndrome of the sick building.

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Anlisis de la influencia de los cambios climticos y de la contaminacin atmosfrica sobre las enfermedades respiratorias en nios atendidos en un servicio de urgencia

Anlisis de la influencia de los cambios climticos y de la contaminacin atmosfrica sobre las enfermedades respiratorias en nios atendidos en un servicio de urgencia

Results in our study show a notable increase in the number of children affected with respiratory diseases during the months of May and June, which in Brazil re- present the months of the winter season where this is normal in all age groups, especially for respiratory di- sease of viral origin. They are the months with a concu- rrent decrease in dispersion of external air pollutants . After exclusion of seasonal variation (irregular distribu- tion during the months), multiple linear regression de- monstrated that the increase in Emergency Department attendance in our hospital relative to Infectious Respira- tory Disease (IRD) was due to decrease in temperature (inverse relationship with minimum temperature) and quantity of particulate material (direct relationship). The- se data reinforce the hypothesis that temperature and levels of external pollutants (particulate material) have a direct influence on IRD episodes in children. These ob- servations corroborate data from the literature and re- sults from clinical observation.

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Emerging pollutants in wastewater  Aquatic toxicity and ozonation

Emerging pollutants in wastewater Aquatic toxicity and ozonation

Single-species tests are effective tools that facilitate reproducible toxicity testing with high precision and throughput, but they cannot reflect the interactions between species (Geiszinger et al., 2009). Such interactions can only be included in toxicity estimates when biological communities composed of many different species are used. The use of natural microbial communities, directly collected from the water body of concern and exposed to emerging substances under controlled conditions, has improved the ecological relevance of laboratory toxicity tests (Sabater et al., 2007 and Proia et al., 2013). On the other hand, aquatic ecosystems are exposed to various multi-component mixtures, whose joint toxicity is typically higher than each its component alone (Kortenkamp et al., 2009). The focus on a substance-by-substance assessment in most studies for aquatic toxicity evaluation therefore runs the risk of underestimating the actual toxic pressure that an ecosystem is exposed to. And even though the concentrations of individual pollutants might be low, combined effects have been shown to occur even when the compounds are present in concentrations below their respective toxicity threshold (Backhaus et al., 2000a,b and Fent et al., 2006) (Fig. 1.3).

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TítuloHydrodynamic behaviour and comparison of technologies for the removal of excess biomass in gas phase biofilters

TítuloHydrodynamic behaviour and comparison of technologies for the removal of excess biomass in gas phase biofilters

The hydrodynamic behaviour of a biofilter fed toluene and packed with an inert carrier was evaluated on start-up and after long-term operation, using both methane and styrene as tracers in Residence Time Distribution experiments. Results indicated some deviation from ideal plug flow behaviour after 2-year operation. It was also observed that the retention time of VOCs gradually increased with time and was significantly longer than the average residence time of the bulk gas phase. Non-ideal hydrodynamic behaviour in packed beds may be due to excess biomass accumulation and affects both reactor modeling and performance. Therefore, several methods were studied for the removal of biomass after long-term biofilter operation: filling with water and draining, backwashing, and air sparging. Several flow rates and temperatures (20–60°C) were applied using either water or different chemicals (NaOH, NaOCl, HTAB) in aqueous solution. Usually, higher flow rates and higher temperatures allowed the removal of more biomass, but the efficiency of biomass removal was highly dependant on the pressure drop reached before the treatment. The filling/draining method was the least efficient for biomass removal, although the treatment did basically not generate any biological inhibition. The efficiency of backwashing and air sparging was relatively similar and was more effective when adding chemicals. However, treatments with chemicals resulted in a significant decrease of the biofilter's performance immediately after applying the treatment, needing periods of several days to recover the original performance. The effect of manually mixing the packing material was also evaluated in duplicate experiments. Quite large amounts of biomass were removed but disruption of the filter bed was observed. Batch assays were performed simultaneously in order to support and quantify the observed inhibitory effects of the different chemicals and temperatures used during the treatments.

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Puertos del mundo y geopolítica portuaria

Puertos del mundo y geopolítica portuaria

For the purposes of this forecast, we define Africa as the entire continent of Africa plus the nations of Cape Verde, Madagascar, Reunion, the Seychelles, Mayotte, Mauritius, the Comoros Islands, and São Tomé and Principe. Data from ACI, IATA, ICAO, governments and airport authorities, the United Nations, and the US Department of Commerce were used to model air cargo flows associated with Africa

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Optimización del mantenimiento de motores MTU 16V4000 en volquetes Komatsu 830E

Optimización del mantenimiento de motores MTU 16V4000 en volquetes Komatsu 830E

Outside Diameter - Chart 2 ...................................... . Static Pressure Tap ............................................. . Air lnlet System Data Sheets ..................................... . Altitude vs. lnlet Restriction ...................................... . The Exhaust System ............................................ . Standard Turbocharger Assembly ................................. . Schematic Turbocharged Air Flow Diagram ........................ . Engine Coolant Flow Schematic .................................. . Coolant System Expansion ...................................... . Coolant System Contraction ..................................... . Cooling System Pressurization Option ............................. . Series 4000 Fan Control lnputs and Outputs ....................... . Schematic Diagram of the Series 4000 Fuel System ................ . High Pressure Fuel System ...................................... . Baffle Type Water Separator ..................................... . Coalescing Type Water Separator ................................ . Priming and Bleed Ports far the Series 4000 Fuel System ............ . Lubrication System ............................................. . Multi-point Mounting Arrangements ............................... . Bending Moment Diagram ....................................... . J38500-F Pro Link ODA for DDEC 111 ............................. . Electronic Control Module ....................................... . A Typical Series 4000 Multi-ECM Engine Sensor Hamess ........... . Typi_cal Multi ECM Construction an� lndust�al

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Mascarilla Laríngea AIR-Q

Mascarilla Laríngea AIR-Q

2.- Jagannathan N, Roth AG, Sohn LE, Pak TY, Amin S, Suresh S: The new air-Q intubating laryngeal airway for tracheal intubation in children with anticipated difficult airway: a case series. Paediatric Anaesth. 2009; 19 (6): 618-22. (PubMed)

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TítuloGeoscience of the Built Environment: Pollutants and Materials Surfaces

TítuloGeoscience of the Built Environment: Pollutants and Materials Surfaces

Abstract: An overview of issues with environmental relevance that arise from the interaction between pollutants and surfaces of the built environment is presented in this paper. Two broad perspectives are considered: decay of materials and recording of pollution characteristics. In relation to the former, we consider the possible implications on human activities restrictions, materials and morphological options, consumption of resources and release of pollutants resulting from the alteration of materials, conservation and restoration procedures. In terms of pollution recording, the interest of the stony materials as passive monitors of pollution, the question of heterogeneous conditions on buildings and the interest of qualitative and quantitative studies are highlighted. The importance of longitudinal studies on new and cleaned surfaces is considered, both for the understanding of materials decay and for the assessment of pollution conditions. The use of tracers to record the characteristics of pollution sources, interaction with materials and pathways of pollutants is also discussed. Finally, some recommendations are presented, based on the issues discussed on this paper that might be relevant for environmental management programs, including environmental education.

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Advancing towards universal screening for organic pollutants in waters

Advancing towards universal screening for organic pollutants in waters

(23) T. Portolés, J.G.J. Mol, J. V. Sancho, F. Hernández. Use of electron ionization and atmospheric pressure chemical ionization in gas chromatography coupled to time-of-flight mass spectrometry for screening and identification of organic pollutants in waters. J. Chromatogr. A, 1339 (2014) 145–153.

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Ice & Air. “Tu herramienta contra el calor”

Ice & Air. “Tu herramienta contra el calor”

Ice & Air posee un poder de negociación intermedio con sus proveedores. Por un lado posee un alto poder de negociación con los proveedores de ventiladores, pues hay gran diversidad de marcas en el mercado a buenos precios al punto que no habría costos por cambiar de proveedor, las otras marcas también son de calidad y dan confianza al pueblo de Nicaragua. Por el otro lado con los recipientes de poliestireno expandido, solo hay una empresa en el país que manufactura estos productos y se llama SIMASA. Debido a que son los únicos en el país nosotros poseemos un poder de negociación bajo. Por estas razones concluimos que nuestro poder de negociación es intermedio con los proveedores de nuestras materias primas. Cabe destacar que para eliminar esta amenaza, la empresa tiene como objetivo a largo plazo comenzar a manufacturar los recipientes de poliestireno en la nuestra planta.

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Fresh Water From Air

Fresh Water From Air

Fresh Water from the air, nace como una idea emprendedora e innovadora de los miembros de equipo como elaboración de un proyecto universitario a inicios de Febrero del año 2015, con el objetivo de distribuir maquinas productoras de agua potable proveniente del aire, en Managua y sus alrededores, para generar una alternativa económica y ecológica. Inicialmente se elige Managua ya que es la capital del país, sin embargo se pretende extender el proyecto a otros departamentos en un mediano o largo plazo.

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ECO AIR

ECO AIR

Recordación de marca: Este indicador permitirá medir que tan presente está Eco air en la mente del consumidor, lo cual permitirá que el producto penetre nuevos mercados y expanda su grupo objetivo. Para garantizar que el indicador se cumpla, se realizara cada trimestre una encuesta de satisfacción de satisfacción del producto y tener mayor posibilidad de la recompra del mismo.

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Effects of atmospheric stability conditions on the pollutants dispersion near roads using CFD

Effects of atmospheric stability conditions on the pollutants dispersion near roads using CFD

In urban centers, the vehicles are the main source of fine (d <10 𝝁m) and ultrafine (d <100 nm) particles, black carbon, carbon monoxide (CO), and nitrogen oxides (NOx) (Karner et al, 2010; EU,2015; Singh et al, 2018). Those air pollutants cause respiratory and cardiovascular problems, chronic diseases and early mortality on the people exposed to theses pollutants (McConnell et al., 2006; Niita et al., 1993; Pearson, Wachtel, & Ebi, 2000; Riediker et al., 2004). Studies have shown that within the urban regions, pedestrians and people living near roads (< 500 m) are exposed to the highest concentration levels of these pollutants (Finn et al, 2009). Therefore, there is an urgent need for the design of countermeasures to reduce pollutant concentration near roads. For example, it has been found that the use of natural or human made barriers located on the sides of the roads has the potential of reducing those concentrations near roads (Baldauf et al., 2016; Hagler et al., 2012; Ranasinghe et al., 2017; Tong et al., 2016). However, the improper design of those barriers could end up increasing those concentrations or moving the concentration peaks to some distance downwind the road.

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Strategies to immobilize humic substances for their application on the reductive biotransformation of recalcitrant pollutants

Strategies to immobilize humic substances for their application on the reductive biotransformation of recalcitrant pollutants

During the last two decades, evidence have reported that addition of redox mediators (RM), such as humic substances (HS) and their quinone model compounds could significantly enhance the reduction rate of several recalcitrant pollutants by accelerating the transfer of electron equivalents derived from microbial substrate oxidation to the electron-accepting contaminants (Van der Zee and Cervantes 2009). However, as pointed out before, the main limitation in the application of HS as RM in continuous systems is that their continuous addition must be provided to increase conversion rates, which is economically and environmentally non-viable. In this sense, some strategies to immobilize HS have previously been reported (Chapter 2, Table 2.3 and 2.4). However, only a few reports have documented that immobilized HS can serve as effective RM during the reductive biotransformation of recalcitrant pollutants in batch incubations (Alvarez et al. 2012, Cervantes et al. 2011b, Cervantes et al. 2013), and several of these strategies of immobilization have not been applied in redox reactions yet (Chapter 2, Table 2.4).

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Air pollution data classification by SOM Neural Network

Air pollution data classification by SOM Neural Network

Abstract-Over the last ten years, Salamanca has been con­ sidered among the most polluted cities in Mexico. This paper presents a Self-Organizing Maps ( SOM ) Neural Network appli­ cation to classify pollution data and automatize the air pollution level determination for Sulphur Dioxide ( S02 ) in Salamanca. Meteorological parameters are well known to be important factors contributing to air quality estimation and prediction. In order to observe the behavior and clarify the influence of wind parameters on the S02 concentrations a SOM Neural Network have been im plemented along a year. The main advantages of the SOM is that it allows to integrate data from different sensors and provide readily interpretation results. Especially, it is powerful mapping and classification tool, which others information in an easier way and facilitates the task of establishing an order of priority between the distinguished groups of concentrations depending on their need for further research or remediation actions in subsequent management steps. The results show a significative correlation between pollutant concentrations and some environmental variables.

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TítuloCharacterization of absorbent polymers for the removal of volatile hydrophobic pollutants from air

TítuloCharacterization of absorbent polymers for the removal of volatile hydrophobic pollutants from air

Different types of bioreactors are available for the removal of α-pinene from waste-gas streams. The oldest reactor configuration is the conventional biofilter (BF), although another popular kind of bioreactor configuration is the biotrickling filter (BTF).4 It has been demonstrated that continuously recirculating liquid phase bioreactors, such as the BTFs, do sometimes perform better than conventional BFs.5 The removal of gas phase α-pinene has been reported in previous studies using both BFs and BTFs. The highest elimination capacity (EC) in a BF under steady-state conditions was reported to be 143 g m −3 h −1 , when the fungal Ophiostoma species was used as the dominant microorganism.2 Langolf and Kleinheinz6 used a lava rock BF inoculated with a consortium of microorganisms, and reported a maximum EC of 132 g m −3 h −1 . In a fungal BTF, the highest elimination capacity reported was 232 g m −3 h −1 , under mesophilic conditions.7 Recent studies have also shown that the addition of an immiscible second-liquid organic phase improves the performance of bioreactors, increasing the solubility of volatile organic pollutants in the liquid phase.7–9 Nevertheless, BTFs that employ an organic solvent as a second phase may suffer from some drawbacks such as the formation of agglomerates of solvent and biomass in the system that generate clogging problems,10 poor mixing arising from high viscosity, and relatively high cost.

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