987 resultados para air quality measurements


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This report examines the human impact on the subarctic environment of the joint border area of Norway, Finland and Russia. The aim is to present the current state and recent changes that have taken place in the region. The main threat to the environment is the Pechenganikel mining and metallurgical industrial combine in the towns of Nikel and Zapolyarny in the Kola Peninsula. Emissions from this complex include high levels of heavy metals, persistent organic pollutants and sulfur dioxide. Pollution, along with climate change, water level regulation and other anthropogenic effects, has affected the aquatic ecosystems in the joint border area. The main heavy metals in the area are copper and nickel, the highest concentrations of which are measured near the combine. Direct discharge of sewage into the river continues and airborne heavy metal particles are also deposited to areas farther away. Climate changeinduced increase in temperature and precipitation in the Kola Peninsula is evident. Water level regulation with seven hydropower plants in the Pasvik River have changed it into a series of lakes and lake-like reservoirs. This report discusses modelling, which was enabled to estimate the effect of climate change on Lake Inarijärvi and the Pasvik River hydrology, water level fluctuation and ecology and to follow the sulfur dioxide emissions emitted from the Pechenganikel. Effects of pollution on the nature and concentrations of the main pollutants were studied and climate change in the border area and its effects on the ecology were estimated. Also the effects of water level regulation on the ecological status of the aquatic ecosystems were addressed.

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The monitoring and control of hydrogen sulfide (H2S) level is of great interest for a wide range of application areas including food quality control, defense and antiterrorist applications and air quality monitoring e.g. in mines. H2S is a very poisonous and flammable gas. Exposure to low concentrations of H2S can result in eye irritation, a sore throat and cough, shortness of breath, and fluid retention in the lungs. These symptoms usually disappear in a few weeks. Long-term, low-level exposure may result in fatigue, loss of appetite, headache, irritability, poor memory, and dizziness. Higher concentrations of 700 - 800 ppm tend to be fatal. H2S has a characteristic smell of rotten egg. However, because of temporary paralysis of olfactory nerves, the smelling capability at concentrations higher than 100 ppm is severely compromised. In addition, volatile H2S is one of the main products during the spoilage of poultry meat in anaerobic conditions. Currently, no commercial H2S sensor is available which can operate under anaerobic conditions and can be easily integrated in the food packaging. This thesis presents a step-wise progress in the development of printed H2S gas sensors. Efforts were made in the formulation, characterization and optimization of functional printable inks and coating pastes based on composites of a polymer and a metal salt as well as a composite of a metal salt and an organic acid. Different processing techniques including inkjet printing, flexographic printing, screen printing and spray coating were utilized in the fabrication of H2S sensors. The dispersions were characterized by measuring turbidity, surface tension, viscosity and particle size. The sensing films were characterized using X-ray photoelectron spectroscopy, X-ray diffraction, atomic force microscopy and an electrical multimeter. Thin and thick printed or coated films were developed for gas sensing applications with the aim of monitoring the H2S concentrations in real life applications. Initially, a H2S gas sensor based on a composite of polyaniline and metal salt was developed. Both aqueous and solvent-based dispersions were developed and characterized. These dispersions were then utilized in the fabrication of roll-to-roll printed H2S gas sensors. However, the humidity background, long term instability and comparatively lower detection limit made these sensors less favourable for real practical applications. To overcome these problems, copper acetate based sensors were developed for H2S gas sensing. Stable inks with excellent printability were developed by tuning the surface tension, viscosity and particle size. This enabled the formation of inkjet-printed high quality copper acetate films with excellent sensitivity towards H2S. Furthermore, these sensors showed negligible humidity effects and improved selectivity, response time, lower limit of detection and coefficient of variation. The lower limit of detection of copper acetate based sensors was further improved to sub-ppm level by incorporation of catalytic gold nano-particles and subsequent plasma treatment of the sensing film. These sensors were further integrated in an inexpensive wirelessly readable RLC-circuit (where R is resistor, L is inductor and C is capacitor). The performance of these sensors towards biogenic H2S produced during the spoilage of poultry meat in the modified atmosphere package was also demonstrated in this thesis. This serves as a proof of concept that these sensors can be utilized in real life applications.

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Rakennustuotteena käytettävien teräskokoonpanojen lisääntyneet CE- merkintävaatimukset ovat aiheuttaneet runsaasti hämmennystä alan toimijoiden keskuudessa. Tämän tutkimuksen tavoitteena oli selvittää teräskokoonpanojen SFS-EN 1090-1 standardin soveltamisala suhteessa konedirektiiviin sekä kartoittaa mahdollisen muutoksen aiheuttamat toimenpiteet ilmansuojelulaitetoimituksissa. Työssä tutustuttiin asetusten teoreettiseen viitekehykseen, standardeihin sekä alan kirjallisuuteen. Teoriaa sovellettiin tulevaisuudentutkimuksen Delfoi- menetelmään, jossa asiantuntijahaastatteluiden perusteella arvioitiin asetuksen soveltamisalaa ja vaatimuksia. Tutkimuksen avaintuloksia ovat standardin SFS-EN 1090-1 vaatimuksenmukaisuuteen vaikuttavien tekijöiden tunnistaminen ja niiden perusteella laaditut ehdotukset yritystoiminnan kehittämiseksi.

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Tutkimuksessa käsitelty kemikaalitehdas on 110 kV:n kantaverkkoon liittyvä tehointensiivinen teollisuuslaitos. Prosessien käyttöön mukautetut sähkönjakeluverkon yliaaltosuodattimet ja niiden käyttökytkennät ovat tärkeässä asemassa loistehon tuoton hallitsemiseksi liittymän loistehoikkunaan ja riittävän yliaaltosuodatuksen järjestämiseksi häviöt minimoiden. Kohteena olleen kemikaalitehtaan sähkönjakeluverkon kompensointia ja yliaaltosuodatusta on viimeksi tutkittu vuonna 2003. Tämän jälkeen verkostokomponentit ovat ikääntyneet, prosessien käyttö sekä pienjänniteverkko ovat muuttuneet ja tehdasta käyttävät osittain eri henkilöt. Nykytilaselvitykselle ja verkon kehityskohteiden analysoinnille on tullut tarve edellisen selvityksen jatkoksi. Tutkimus painottuu vahvasti kenttämittauksiin, joiden perusteella sekä kirjallisuutta ja tehtaan järjestelmiä hyödyntäen määritetään loistehotasot verkon keskeisimmissä kohteissa pien-, keski- ja suurjännitetasoilla. Tutkimuksessa esitetään lipeätehtaan suotimien uudelleenjärjestely 4. yliaallon vähentämiseksi ja yksikkökoon pienentämiseksi. Kantaverkon liittymäpisteen tilanne oli hyväksyttävä. Tutkimus esittää pienjännitekompensointia KF-4-100 keskukseen varayhteyden kapasiteettia lisäten. Tutkimus tuotti yleistietoutta verkon käytöstä ja selvitti parhaat käyttökytkennät loistehoikkunan hallitsemiseksi ilman loistehokustannuksia.

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Diplomityön tavoitteena oli selvittää, kuinka sähkösuodattimella voidaan vaikuttaa sisäilman laatuun ja kuinka kilpailukykyinen vaihtoehto pienkiinteistöissä sähkösuodatin on perinteisiin kuitusuodattimiin verrattuna. Teoriaosassa tarkasteltiin, kuinka ilman hengitettävät hiukkaset muodostuvat ja miten ne vaikuttavat sisäilman laatuun sekä ihmisten terveyteen. Tarkasteltiin hiukkasten koon, lukumäärän, massan ja pinta-alan yhteyksiä niiden terveysvaikutuksiin. Ultrapienet hiukkaset ovat terveydelle haitallisimpia, koska hiukkasten lukumäärä ja pinta-ala lisäävät terveyshaittoja enemmän kuin hiukkasten massa. Tutkittiin pienkiinteistöjen ilmanvaihtoratkaisuja ja erilaisia tuloilmanpuhdistus-menetelmiä. Soveltavassa osassa tarkasteltiin sähkösuodattimen toimintaa ja sen mahdollisuuksia sisäilman parantajana verrattuna perinteisiin kuitusuodattimiin. Tehtiin sähkösuodattimen ja kuitusuodattimen välinen elinkaarikustannusvertailu keskisuurelle omakotitalolle. Kirjallisuuden ja tutkimushavaintojen perusteella sähkösuodattimen suurin etu muihin suodattimiin verrattuna on sen kyky poistaa kaiken kokoisia, myös ultrapieniä, hengitettäviä hiukkasia ja siten tehokkaasti vähentää hengitettävien hiukkasten lukumäärää ja pinta-alaa. Tällä voi olla vaikutusta yleisten terveyshaittojen ja ympäristöherkkyyden ennaltaehkäisemisessä. Ympäristöherkkyyteen sairastuneiden oireiluun sähkösuodatin voi tuottaa helpotusta kotioloissa ja siirrettävän ilmanpuhdistimen avulla myös työpaikoilla. Elinkaarikustannusvertailun perusteella selvisi, että sähkösuodatin on kalliimmasta hinnastaan huolimatta kokonaiskustannuksiltaan selvästi edullisempi vaihtoehto kuin kuitusuodattimet. Sähkösuodattimen haasteena on uuden teknologian lanseeraaminen pientalorakentamiseen. Pienrakennusten tuloilman puhdistusmenetelmien kehittämisellä olisi mahdollista parantaa suomalaisten elämänlaatua ja saavuttaa merkittäviä säästöjä terveydenhoitokuluissa.

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Ambient (03) ozone concentrations were compared to ozone damage on milkweed plants to determine if there was a correlation. Eight survey sites of at least 100 plants each were located within 5 kilometers of Air Quality Index (AQI) stations in southern Ontario. Sites were visited nine times from June-September (2007) and milkweed leaves from 75 plants were assessed using methods pioneered in the United States. Ambient 0 3 results were calculated into SUM65, seasonal cumulative 0 3, and total 03. The 0 3 exposure indices SUM65 and cumulative 0 3 were tested statistically to determine which index is biologically relevant to milkweed as an 0 3 damage indicator species. The milkweed damage indices were incidence of leaves damaged per plant, incidence of plants damaged per site, and total 0 3• The incidence of plants injured per site was the best damage parameter with an F(1,28)=17.37, p=0.0003 for SUM65 and F(1,28)=7.5, p=O.0106 for cumulative 03 .. Milkweed plants showed quantifiable ozone damage with minimal spatial differences in damage and thus have potential use as a biomonitor species in southern Ontario.

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Ce mémoire décrit et analyse différents types de systèmes d'échange de droits d'émission utilisés dans le cadre de politiques de gestion de la pollution atmosphérique. L'objectif premier est de répertorier des enjeux juridiques étant liés à l'efficacité de ces systèmes. Dans un premier temps, nous nous attardons à la structure et aux mécanismes internes des systèmes d'échange de droits d'émission. Tout d'abord, nous soulignons le fondement théorique de ce type de système. Nous évaluons par la suite la structure et certains litiges liés au système d'échange américain dans le cadre des émissions de dioxyde de soufre. Dans un deuxième temps, nous continuons la description de systèmes en nous attardant plus spécifiquement aux interactions entre les systèmes d'échange de droits d'émission et les autres politiques et règlementations environnementales (incluant d'autres systèmes d'échange d'émission) visant la même problématique environnementale.

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The hazards associated with major accident hazard (MAH) industries are fire, explosion and toxic gas releases. Of these, toxic gas release is the worst as it has the potential to cause extensive fatalities. Qualitative and quantitative hazard analyses are essential for the identitication and quantification of the hazards associated with chemical industries. This research work presents the results of a consequence analysis carried out to assess the damage potential of the hazardous material storages in an industrial area of central Kerala, India. A survey carried out in the major accident hazard (MAH) units in the industrial belt revealed that the major hazardous chemicals stored by the various industrial units are ammonia, chlorine, benzene, naphtha, cyclohexane, cyclohexanone and LPG. The damage potential of the above chemicals is assessed using consequence modelling. Modelling of pool fires for naphtha, cyclohexane, cyclohexanone, benzene and ammonia are carried out using TNO model. Vapor cloud explosion (VCE) modelling of LPG, cyclohexane and benzene are carried out using TNT equivalent model. Boiling liquid expanding vapor explosion (BLEVE) modelling of LPG is also carried out. Dispersion modelling of toxic chemicals like chlorine, ammonia and benzene is carried out using the ALOHA air quality model. Threat zones for different hazardous storages are estimated based on the consequence modelling. The distance covered by the threat zone was found to be maximum for chlorine release from a chlor-alkali industry located in the area. The results of consequence modelling are useful for the estimation of individual risk and societal risk in the above industrial area.Vulnerability assessment is carried out using probit functions for toxic, thermal and pressure loads. Individual and societal risks are also estimated at different locations. Mapping of threat zones due to different incident outcome cases from different MAH industries is done with the help of Are GIS.Fault Tree Analysis (FTA) is an established technique for hazard evaluation. This technique has the advantage of being both qualitative and quantitative, if the probabilities and frequencies of the basic events are known. However it is often difficult to estimate precisely the failure probability of the components due to insufficient data or vague characteristics of the basic event. It has been reported that availability of the failure probability data pertaining to local conditions is surprisingly limited in India. This thesis outlines the generation of failure probability values of the basic events that lead to the release of chlorine from the storage and filling facility of a major chlor-alkali industry located in the area using expert elicitation and proven fuzzy logic. Sensitivity analysis has been done to evaluate the percentage contribution of each basic event that could lead to chlorine release. Two dimensional fuzzy fault tree analysis (TDFFTA) has been proposed for balancing the hesitation factor invo1ved in expert elicitation .

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Bei Meßprojekten in denen Gebäude mit installierter Lüftungsanlage untersucht wurden, stellte man immer wieder ein breite Streuung der Meßwerte, als auch eine oftmals deutliche Abweichung vom vorher ermittelten Heizwärmebedarf der Gebäude fest. Es wird vermutet, daß diese Unterschiede systemspezifische Ursachen haben, ein Nachweis kann aufgrund der geringen Anzahl vorhandener Meßpunkte jedoch nicht geführt werden. Um die Sensitivität verschiedener Randbedingungen auf den Energieverbrauch zu ermitteln, wird im vorliegenden Forschungsprojekt ein Simulationsmodell erstellt. Das thermische Verhalten und die Durchströmung des Gebäudes werden durch ein gekoppeltes Modell abgebildet. Unterschiedliche Lüftungsanlagensysteme werden miteinander verglichen. Auf Basis vorhandener Meßdaten wird ein klimaabhängiges Modell zur Fensterlüftung entwickelt, welches in die Modellbildung der Gebäudedurchströmung mit einfließt. Feuchtegeregelte Abluftanlagen sind in der Lage den mittleren Luftwechsel auf ein hygienisch sinnvollen Wert zu begrenzen. Sie erweisen sich im Hinblick auf die Sensitivität verschiedener Randbedingungen als robuste Systeme. Trotz Einsatz von Lüftungsanlagen kann je nach Betriebszustand insbesondere bei Abluftanlagen keine ausreichende Luftqualität sichergestellt werden. Zukünftige Systeme dürfen das "Lüftungssystem" Fenster nicht vernachlässigen, sondern müssen es in das Gesamtkonzept mit einbeziehen.

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Introducción: la contaminación atmosférica no solo tiene efectos sobre el sistema respiratorio sino también sobre el cardiovascular. El objetivo de este estudio es generar evidencia que permita establecer una asociación entre el infarto agudo del miocardio y la concentración de PM10 en el ambiente como un estudio preliminar para un grupo de pacientes en Bogotá. Metodología: la asociación entre la concentración del material particulado (en este caso PM10 medido en la estación más cercana del lugar reportado por el paciente) y el infarto agudo del miocardio se estableció utilizando el diseño case crossover. Se utilizó información de las historias clínicas de los pacientes con infarto agudo del miocardio que ingresaron al Servicio de Urgencias de la FSFB, y las concentraciones de PM10 medido en la estación más cercana al lugar de inicio de los síntomas de síndrome coronario agudo, reportado por el paciente. Resultados: se encontró que la asociación entre la concentración de PM10 y el diagnóstico de infarto agudo del miocardio es estadísticamente significativa teniendo en cuenta tres momentos de control: 2 horas antes del evento, 24 horas antes del evento y 48 horas antes del evento. Discusión: este estudio sugiere que las altas concentraciones de material particulado en el ambiente son un factor de riesgo para el desarrollo de infarto agudo del miocardio especialmente en personas con enfermedad coronaria subyacente. Con esta investigación se demuestra la importancia de generar acciones que disminuyan la contaminación de la ciudad y de esta forma proteger la salud de las personas.

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Introducción: En Colombia la investigación sobre condiciones de trabajo y salud en minería carbonífera es escasa y no considera la percepción de la población expuesta y sus comportamientos frente a los riesgos inherentes. Objetivo: Determinar la asociación entre las condiciones de trabajo y morbilidad percibidas entre trabajadores de minas de carbón en Guachetá, Cundinamarca. Materiales y métodos: Se realizó un estudio transversal con 154 trabajadores seleccionados aleatoriamente del total registrado en la alcaldía municipal. Se indagó sobre características sociodemográficas, condiciones de trabajo y salud en las minas. Se estimaron prevalencias de los trastornos respiratorios, osteomusculares y auditivos, y se exploraron las asociaciones entre algunas condiciones de trabajo y los eventos con prevalencia superior a 30% de forma bivariada y múltiple, con regresiones Poisson con varianza robusta. Resultados: Los trabajadores fueron en su mayoría hombres, con edades entre 18 y 77 años de edad. Los problemas de salud más frecuentemente reportados fueron dolor lumbar (46,10%), dolor del miembro superior (40,26%), dolor del miembro inferior (34,42%), trastornos respiratorios (17,53%) y problemas auditivos (13,64%). Existen diferencias importantes en la percepción dependiendo de la antigüedad laboral y las condiciones subterráneas o no del trabajo. Conclusión: Los riesgos más reconocidos por los trabajadores son los relacionados con trastornos osteomusculares, al parecer por ser más evidentes en su cotidianidad. Las acciones en salud ocupacional podrán considerar estos hallazgos en sus planes de prevención de la enfermedad en las minas del carbón colombianas.

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Un problema de salud ambiental relevante es la contaminación del aire generado por diferentes factores, uno de ellos es la carga microbiana. El estudio evidencia la presencia de estos contaminantes del aire como son los bioaerosoles cultivables y contables en las áreas de los edificios administrativos estudiados la cual podría afectar la calidad del aire interior. Se realizó un estudio observacional de corte transversal que permitió conocer y establecer las características de la carga microbiana presente relacionada con bioaerosoles cultivables y contables en los sistemas de ventilación mecánica en tres edificios administrativos de la ciudad de Bogotá en el periodo 2012 a 2013 y, la asociación o no entre variables de interés. Los bioaerosoles cultivables y contables encontrados con mayores porcentajes en las muestras tomadas fueron comunes a los tres edificios así: Aspergillus sp. se encontró en el 77,2% (61) de las muestras para el edifico uno, mientras que para el dos fue de 91% (30) de las muestras y para el edificio tres 100% (19) de las muestras tomadas; seguido por el género Penicillium sp. del cual se encontró 60,8% (48) de las muestras para el edificio uno, para el edificio dos 87,9% (29) de las muestras y para el edificio tres 94,7% (18) de las muestras. Otro género encontrado en porcentajes altos en los tres edificios fue el Cladosporium sp. , en el edificio uno 41,8% (33) de las muestras, mientras que para el edificio dos correspondió al 100% (33) de las muestra y finalmente para el edificio tres 84,2% (16) de las muestras analizadas. Los hallazgos se correlacionan con lo reportado por la literatura.

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Aviation and the environment: outline - Aircraft noise - Aircraft engine emissions Local air quality Greenhouse gases and climate change - Airline, airport and manufacturer impacts

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O Homem tem privilegiado a vida no meio urbano, em detrimento do rural, por mais oportunidade de emprego e melhores condições de vida. As cidades cresceram de forma acelerada, sobretudo depois da Revolução Industrial do século XVIII, crescimento sem controlo, repercutindo-se num desajustado planeamento urbano, ambiental, humano, social e económico. De uma forma, as paisagens verdes e naturais, foram substituídas por densas manchas cinzentas de construção, criando afastamento crescente do Homem com a Natureza. Os Jardins Verticais poderão ter um papel fundamental revestindo de forma verde e natural as fachadas dos edifícios, numa tentativa de colmatar o afastamento entre ambos. Para além destes aspectos, os Jardins Verticais proporcionam inúmeras vantagens para o edifício, de que se destacam a eficiência energética e acústica, a protecção da estrutura do edificado ou a melhoria da qualidade do ar interior. Estes também importantes para a envolvente, como na redução do efeito ilha de calor, no aumento da biodiversidade, na melhoria da qualidade do ar exterior, mas sobretudo porque proporcionam ao Homem uma sensação de saúde e conforto, exclusivo da Natureza. Tendo em conta o estado de degradação do edificado nas grandes cidades, e tomando como exemplo particular a cidade do Porto, o recurso aos Jardins Verticais poderá ser uma solução viável para a reabilitação urbana, mudando a imagem de degradação, propondo uma imagem mais “verde” e contribuindo para o nível de sustentabilidade. Partindo deste pressuposto, propõe-se como aplicação do conhecimento adquirido no estudo desenvolvido e aqui apresentado, o recurso a Jardins Verticais como estratégia de reabilitação de edifícios da cidade do Porto. Inspirado na técnica e mestria de Patrick Blanc, resultou um “pormenor-tipo”, como base para a aplicação de Jardins Verticais no edificado social da cidade, experimentado em 10 estudos práticos, tirando-se partido das vantagens supra-mencionadas.

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The North Atlantic Oscillation (NAO) is an important large-scale atmospheric circulation that influences the European countries climate. This study evaluated NAO impact in air quality in Porto Metropolitan Area (PMA), Portugal, for the period 2002-2006. NAO, air pollutants and meteorological data were statistically analyzed. All data were obtained from PMA Weather Station, PMA Air Quality Stations and NOAA analysis. Two statistical methods were applied in different time scale : principal component and correlation coefficient. Annual time scale, using multivariate analysis (PCA, principal component analysis), were applied in order to identified positive and significant association between air pollutants such as PM10, PM2.5, CO, NO and NO2, with NAO. On the other hand, the correlation coefficient using seasonal time scale were also applied to the same data. The results of PCA analysis present a general negative significant association between the total precipitation and NAO, in Factor 1 and 2 (explaining around 70% of the variance), presented in the years of 2002, 2004 and 2005. During the same years, some air pollutants (such as PM10, PM2.5, SO2, NOx and CO) present also a positive association with NAO. The O3 shows as well a positive association with NAP during 2002 and 2004, at 2nd Factor, explaining 30% of the variance. From the seasonal analysis using correlation coefficient, it was found significant correlation between PM10 (0.72., p<0.05, in 2002), PM2.5 (0 74, p<0.05, in 2004), and SO2 (0.78, p<0.01, in 2002) with NAO during March-December (no winter period) period. Significant associations between air pollutants and NAO were also verified in the winter period (December to April) mainly with ozone (2005, r=-0.55, p.<0.01). Once that human health and hospital morbidities may be affected by air pollution, the results suggest that NAO forecast can be an important tool to prevent them, in the Iberian Peninsula and specially Portugal.