Hydrochlorofluorocarbons
Mostrando 1-6 de 6 artigos, teses e dissertações.
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1. AnÃlise experimental de sistemas de refrigeraÃÃo operando com R-290 e R-600a como fluidos refrigerantes alternativos
Refrigerants CFC (chlorofluorocarbons), as R-12, deplete the ozone layer which protects the surface of the earth, due to the presence of chlorine in their structure. The HCFC (hydrochlorofluorocarbons), as R-22, also have chlorine in their molecule and must be replaced as a refrigerant fluid. In Europe, brand new equipments are not produced with HCFC-22, sin
Publicado em: 2008
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2. Esterilização por óxido de etileno: estudo da efetividade esterilizante de misturas não explosivas e compatíveis com a camada de ozônio / Ethylene oxide sterilization: effectivity study of non explosive blends and compatible with ozone layer
Tendo em vista a importância do processo esterilizante aplicado a produtos farmacêuticos e aos produtos médico-hospitalares, distintos métodos foram desenvolvidos de forma a possibilitar sua aplicação, inclusive a materiais termossensíveis. Neste contexto, o processo que se tornou mais amplamente empregado consiste naquele utilizando o óxido de etile
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/04/2000
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3. Microbial degradation of hydrochlorofluorocarbons (CHCl2F and CHCl2CF3) in soils and sediments.
The ability of microorganisms to degrade trace levels of the hydrochlorofluorocarbons HCFC-21 and HCFC-123 was investigated. Methanotroph-linked oxidation of HCFC-21 was observed in aerobic soils, and anaerobic degradation of HCFC-21 occurred in freshwater and salt marsh sediments. Microbial degradation of HCFC-123 was observed in anoxic freshwater and salt
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4. Tissue acylation by the chlorofluorocarbon substitute 2,2-dichloro-1,1,1-trifluoroethane.
Hydrochlorofluorocarbons (HCFCs) are being developed as substitutes for ozone-depleting chlorofluorocarbons (CFCs); because widespread human exposure to HCFCs may be expected, it is important to evaluate their toxicities thoroughly. Here we report studies on the bioactivation of the CFC substitute 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123) to an electroph
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5. Investigations of the environmental acceptability of fluorocarbon alternatives to chlorofluorocarbons.
Chlorofluorocarbons (CFCs) are currently used in systems for preservation of perishable foods and medical supplies, increasing worker productivity and consumer comfort, conserving energy and increasing product reliability. As use of CFCs is phased out due to concerns of ozone depletion, a variety of new chemicals and technologies will be needed to serve thes
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6. Designing safer chemicals: predicting the rates of metabolism of halogenated alkanes.
A computational model is presented that can be used as a tool in the design of safer chemicals. This model predicts the rate of hydrogen-atom abstraction by cytochrome P450 enzymes. Excellent correlations between biotransformation rates and the calculated activation energies (delta Hact) of the cytochrome P450-mediated hydrogen-atom abstractions were obtaine