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Desenvolvimento de dispositivo para extração e coleta de fumos de asfalto e aplicação na determinação de hidrocarbonetos policíclicos aromáticos / Device development for extraction and collection of asphalt fumes and application in determination of polycyclic aromatic hydrocarbonsFerraz, Luis Manoel do Rosário 16 March 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The given work presents the development and usage of a device (DEC Device for Extraction and Collection) capable of generate and collect fumes produced by the heating of asphalt cement samples. The DEC was elaborated aiming its employment on laboratory bench. The heating of the asphalt binder in a closed system generates the fumes. This process occurs under controlled temperature and non-oxidizing atmosphere with hot argon gas as carrier. The fumes are then extracted from small portions of asphalt binder. The developed system was applied on the generation and collection of asphalt binder fumes commercially available in Brazil. The levels of some polycyclic aromatic hydrocarbons (PAH) for the collected fumes were determined. According to the World Health Organization, these compounds must be monitored, regarding their carcinogenic potential. The DEC can operate over a wide temperature range that covers all usual asphalt application temperatures, without any significant losses of the components and without risk of ignition, due to the inert atmosphere. Besides, the present device may operate using different solvents for extraction or even no solvents, through the heating of the sample in question. In addition, the effect of the asphalt cement mass temperature on the PAH levels was discussed in this work. The DEC allows the fume collection either straight from the liquid phase (absorbent solutions) or in solid phase (adsorbent solids). The analysis of the collected fumes using the DEC reported 14 out of the 16 PAH considered high priority by the EPA (Environmental Protection Agency). / O presente trabalho trata da construção e utilização de um dispositivo (DEC-Dispositivo de Extracão e Coleta) capaz de gerar e coletar fumos produzidos pelo aquecimento de amostras de cimento asfáltico. O DEC foi desenvolvido para utilização em bancada de laboratório, e a geração dos fumos se da através do aquecimento do ligante asfáltico em sistema fechado, com temperatura controlada em atmosfera não oxidante utilizando-se para isso argônio aquecido como gás de arraste. As extrações dos fumos são feitas a partir de pequenas massas de ligante asfáltico. O sistema desenvolvido foi aplicado na geração e coleta de fumos de ligantes asfálticos comercializados no Brasil. Os fumos coletados foram analisados quanto aos teores de alguns hidrocarbonetos policíclicos aromáticos (HPA) cujo monitoramento é recomendado pela Organização Mundial da Saúde devido ao seu potencial carcinogênico. O DEC pode ser operado numa ampla faixa de temperaturas que cobre todas as temperaturas usuais de aplicação de asfalto, sem perdas significativas dos analitos e sem risco de ignição em virtude da atmosfera inerte presente. O dispositivo pode operar com diferentes solventes em contato com a massa de cimento asfáltico, e também sem a presença destes solventes, pelo aquecimento direto da amostra. A influencia do efeito da temperatura da massa de cimento asfáltico sobre o teor de HPA observado, foi discutido neste trabalho. O DEC permite a coleta dos fumos tanto diretamente em fase liquida (soluções absorventes) quanto em fase solida (adsorventes sólidos). Na análise dos fumos coletados no DEC foram encontrados 14 dos 16 HPA considerados prioritários pela EPA (Environmental Protection agency).
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Estudo dos fumos e gases gerados no processo de soldagem Gas Metal Arc Welding (GMAW) em duas empresas do segmento metal mecânico de PernambucoALVES, Sérvulo José Ferreira 29 February 2016 (has links)
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Tese PPGEM Doutorado Sérvulo José Ferreira Alves 2016.pdf: 1519348 bytes, checksum: 490570bb98ca33461aa0ff92d42da7d8 (MD5)
Previous issue date: 2016-02-29 / Na união de materiais metálicos, sobretudo nos aços, os processos de soldagens
são predominantes e com grande destaque para soldas ao arco elétrico. E dentre os
processos de soldas ao arco elétrico há no segmento metal mecânico mundial uma
enorme utilização do GMAW que necessita de gases de proteção que evitam a
contaminação das áreas soldadas pelos gases presentes na atmosfera, em especial
o nitrogênio, o oxigênio e o hidrogênio. O GMAW por sua vez é subdividido em dois
tipos de processos de soldagens que dependem das características físicas e
químicas dos gases de proteção, bem como, do metal de base a ser soldado. O
primeiro deles quando se usa como gás de proteção um gás inerte como o argônio e
o hélio ou uma mistura de gases inertes sendo denominado então MIG. Já o
segundo tipo ocorre quando no gás de proteção há a presença de um gás ativo
como o oxigênio ou o dióxido de carbono ou uma mistura de gases ativos e inertes e
é conhecido como MAG. Foi realizada a coleta e a análise em Pernambuco dos
fumos (particulados) e gases gerados na soldagem GMAW, no soldador, em duas
empresas do segmento metal mecânico de Pernambuco de acordo com a NR-15 e a
ACGIH. A caracterização dos fumos foi obtida por ICP-OES enquanto, a dos gases
ocorreu por cromatografia em fase gasosa. O objetivo deste trabalho foi coletar e
analisar qualitativa e quantitativamente os fumos e os gases gerados no soldador no
processo de soldagem GMAW. E desenvolver uma metodologia eficiente e de baixo
custo na coleta e acondicionamento das amostras dos gases no soldador de duas
empresas do segmento metal mecânico de Pernambuco. A conclusão deste trabalho
se baseou nas análises dos fumos e dos gases, em cada um dos soldadores. E
indicou que nas duas empresas, cada soldador não estava exposto a fumos acima
dos limites da NR-15 e da ACGIH. As análises do CO2 e do CO, indicaram que o
soldador da empresa “A” não excedia os limites toleráveis da ACGIH e da NR-15. O
soldador da empresa “B” ficou exposto apenas ao CO acima do limite da ACGIH e
quanto ao CO2 não excedeu os limites da NR-15 e da ACGIH. / In the union of metallic materials, mainly in steel, welding processes are predominant
and with great emphasis on the electric arc welds. And among the processes of arc
welding to metal segment in the world there is a huge mechanical use of GMAW that
requires shielding gas to prevent contamination of the welded areas by gases
present in the atmosphere, in particular nitrogen, oxygen and hydrogen. The GMAW
is in turn subdivided into two types of welding processes that depend on the physical
and chemical characteristics of shielding gases, as well, as the base metal being
welded. The first of them when used as a shielding gas as an inert gas argon and
helium or a mixture of inert gases then being called MIG. The second type occurs
when there is the presence of an active gas such as oxygen or carbon dioxide or a
mixture of active and inert gas in the shielding gas and is known as MAG. Was
performed the collection and analysis in Pernambuco of the fumes (particulate) and
gases generated in GMAW welding, in the welder, in two companies of Pernambuco
mechanical metal segment of according to NR -15 and the ACGIH. The aim of this
work was to collect and analyze qualitatively and quantitatively the fumes and gases,
in the welder, in GMAW welding process. And develop an efficient methodology and
low cost in the collection and packaging of the samples of gases, in the welder, in the
GMAW welding in two metal mechanic segment companies Pernambuco. The
characterization of the smoke was obtained by ICP-OES while the gases occurred by
gas chromatography. The conclusion of this work was based on analysis of the
fumes and gases in each of the welders. And indicated that the two companies, each
welder was not exposed to fumes and gases or CO and CO2 above the limits of the
NR-15 and ACGIH. Analyses of CO2 and CO indicated that the welder of the
company "A" did not exceed the tolerable limits of the ACGIH and NR-15. Welder the
company "B" was exposed only to CO above the ACGIH limit and how much CO2
has exceeded the scope of the NR-15 and ACGIH.
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Stanovení emisí a škodlivých částic výfukových plynů u CNG, benzinových a naftových vozidel / Determination of emissions and harmful particles of exhaust gases of CNG, petrol and diesel vehiclesRozsíval, Adam January 2019 (has links)
The thesis deals with an analyses of emission and harmful particles of exhaust fumes of automobiles with an environmental impact. More precisely, it describes the basic characteristics of current fuel types and emission produced by internal combustion engines. Next, it deals with the measures and possibilities of decreasing car traffic emission with respect to environmental impact. It also describes the current European standards for emission and the systems of the cars that are able to decrease emission. The work also deals with the measuring of emission and the methods that are used. According to the measuring methods, the analysis of exhalation is done and it is based on the data of the real car fleet. Values of the emission analyses are compared. The financial aspect is a part of the analyses.
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Occupational exposure to combustion by-products and breast cancer risk in postmenopausal womenPaul-Cole, Kahlila 12 1900 (has links)
Contexte : L’exposition professionnelle aux sous-produits de combustion est répandue et peut contribuer à l'étiologie du cancer du sein. Cette étude vise à estimer l’association entre l’exposition professionnelle à certains sous-produits de combustion et le risque postménopausique de cancer du sein.
Méthodes : Cette étude cas-témoins populationnelle comprenait des femmes ménopausées âgées de 47-75 ans résidant à Montréal, Québec (2008-2011). Les cas incluaient 695 femmes ayant reçu un diagnostic cancer du sein malin et 608 témoins sélectionnés aléatoirement à partir de la Liste électorale du Québec, appariés aux cas en fréquence (groupes d'âge de 5 ans). L’information sur les facteurs de risque et l'historique professionnel a été recueillie par entrevue. Des hygiénistes industriels ont évalué l'exposition à 293 agents, dont six sous-produits de combustion. Le risque de cancer du sein associé à l'exposition professionnelle à certains sous-produits a été estimé, pour l'ensemble des tumeurs et leurs sous-types moléculaires, par régression logistique inconditionnelle avec rapports de cotes ajustés (RC) et intervalles de confiance à 95 % (IC 95%).
Résultats : Des associations positives suggestives ont été trouvées entre l'exposition aux hydrocarbures aromatiques polycycliques et certains sous-types moléculaires de tumeurs : toutes tumeurs, RC=1,18 (IC95%=0,80-1,76), tumeurs luminales A, RC=1,25 (IC95%=0,81-1,93) et tumeurs luminales B, RC=2,09 (IC95%=0,87-4,60). Un risque élevé a été observé avec l'exposition aux fumées de cuisson pour les tumeurs HER2-enrichies (RC=2,63, IC95%=0,98-6,40).
Conclusion : L'exposition à certains sous-produits de combustion peut augmenter le risque de certains sous-types moléculaires de cancer du sein. Des études futures explorant cette association sont justifiées. / Background: Postmenopausal breast cancer is the most common cancer among women, yet little is known about its association with occupational exposures. Exposure to combustion by-products is widespread in occupational settings and may contribute to breast cancer etiology. Here, we sought to estimate the association between lifetime occupational exposure to select combustion by-products and the risk of postmenopausal breast cancer.
Methods: This population-based case-control study included postmenopausal women residing in Montreal, Quebec (2008-2011). Cases comprised 695 women aged 47-75 years diagnosed with incident malignant breast cancer, and 608 controls randomly selected from the Quebec Electoral List, frequency-matched to cases (5-year age groups). Information on risk factors and employment history was collected by interview. Exposure to 293 agents, including six combustion by-products was assessed by industrial hygienists. Unconditional logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for breast cancer risk, both overall and by tumor molecular subtypes, to occupational exposure to select combustion by-products.
Results: We found suggestive positive associations between exposure to polycyclic aromatic hydrocarbons and certain molecular subtypes of tumors: for all tumors, OR=1.18 (95% CI: 0.80-1.76), Luminal A tumors, OR=1.25 (95% CI: 0.81-1.93) and Luminal B tumors, OR=2.09 (95% CI: 0.87-4.60). Elevated risked were observed for exposure to cooking fumes for HER2-enriched tumors (OR=2.63, 95% CI: 0.98-6.40).
Conclusion: Exposure to select combustion by-products may increase the risk of certain hormonal subtypes of breast cancer. Future studies exploring this association are warranted.
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