Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente
Autor(a) principal: | |
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Data de Publicação: | 2001 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Química Nova (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422001000400003 |
Resumo: | A sensitive and simple system was proposed for the in situ measurement of total aldehyde in outdoor or indoor ambient. The method is based on the use of a reagent drop as an useful interface to preconcentrate the sample prior to determination of total aldehyde as formaldehyde. The drop is formed at the tip of a cylindrical tube that contains two optical fibers placed on opposite sides and in contact with the reagent solution. One optical fiber carries the red light to the drop form a light emitting diode (LED). The transmitted light is measured by a second optical fiber/photodiode system. The analytical signal is read and converted into absorbance. The reagent solution of 3-methyl-2-benzothiazoline hydrazone (MBTH) forms a blue cation during reaction with formaldehyde that can be measured at 660 nm. Some aspects of kinetics reaction formation of dye were reevaluated. The formaldehyde reacts with MBTH and forms the azine in about 12 min. The oxidation of MBTH by Fe (III) and the formation of dye requires 3 min. The absorbance of the reagent drop is proportional to the sampling time and to the analyte concentration. The absorbance signal increases with increased sample gas flow until a maximum is reached then decreases until it forms a plateau. The proposed method was evaluated using both outdoor and indoor samples, and it was shown to viable provide an accurate measure of total aldehyde. |
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Gota suspensa para avaliação de aldeído total no ar interno e externo do ambientealdehydesuspended dropletair analysisA sensitive and simple system was proposed for the in situ measurement of total aldehyde in outdoor or indoor ambient. The method is based on the use of a reagent drop as an useful interface to preconcentrate the sample prior to determination of total aldehyde as formaldehyde. The drop is formed at the tip of a cylindrical tube that contains two optical fibers placed on opposite sides and in contact with the reagent solution. One optical fiber carries the red light to the drop form a light emitting diode (LED). The transmitted light is measured by a second optical fiber/photodiode system. The analytical signal is read and converted into absorbance. The reagent solution of 3-methyl-2-benzothiazoline hydrazone (MBTH) forms a blue cation during reaction with formaldehyde that can be measured at 660 nm. Some aspects of kinetics reaction formation of dye were reevaluated. The formaldehyde reacts with MBTH and forms the azine in about 12 min. The oxidation of MBTH by Fe (III) and the formation of dye requires 3 min. The absorbance of the reagent drop is proportional to the sampling time and to the analyte concentration. The absorbance signal increases with increased sample gas flow until a maximum is reached then decreases until it forms a plateau. The proposed method was evaluated using both outdoor and indoor samples, and it was shown to viable provide an accurate measure of total aldehyde.Sociedade Brasileira de Química2001-08-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422001000400003Química Nova v.24 n.4 2001reponame:Química Nova (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0100-40422001000400003info:eu-repo/semantics/openAccessPereira,Elisabete A.Cardoso,Arnaldo A.Dasgupta,Parnendu K.por2001-08-31T00:00:00Zoai:scielo:S0100-40422001000400003Revistahttps://www.scielo.br/j/qn/ONGhttps://old.scielo.br/oai/scielo-oai.phpquimicanova@sbq.org.br1678-70640100-4042opendoar:2001-08-31T00:00Química Nova (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
title |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
spellingShingle |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente Pereira,Elisabete A. aldehyde suspended droplet air analysis |
title_short |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
title_full |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
title_fullStr |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
title_full_unstemmed |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
title_sort |
Gota suspensa para avaliação de aldeído total no ar interno e externo do ambiente |
author |
Pereira,Elisabete A. |
author_facet |
Pereira,Elisabete A. Cardoso,Arnaldo A. Dasgupta,Parnendu K. |
author_role |
author |
author2 |
Cardoso,Arnaldo A. Dasgupta,Parnendu K. |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Pereira,Elisabete A. Cardoso,Arnaldo A. Dasgupta,Parnendu K. |
dc.subject.por.fl_str_mv |
aldehyde suspended droplet air analysis |
topic |
aldehyde suspended droplet air analysis |
description |
A sensitive and simple system was proposed for the in situ measurement of total aldehyde in outdoor or indoor ambient. The method is based on the use of a reagent drop as an useful interface to preconcentrate the sample prior to determination of total aldehyde as formaldehyde. The drop is formed at the tip of a cylindrical tube that contains two optical fibers placed on opposite sides and in contact with the reagent solution. One optical fiber carries the red light to the drop form a light emitting diode (LED). The transmitted light is measured by a second optical fiber/photodiode system. The analytical signal is read and converted into absorbance. The reagent solution of 3-methyl-2-benzothiazoline hydrazone (MBTH) forms a blue cation during reaction with formaldehyde that can be measured at 660 nm. Some aspects of kinetics reaction formation of dye were reevaluated. The formaldehyde reacts with MBTH and forms the azine in about 12 min. The oxidation of MBTH by Fe (III) and the formation of dye requires 3 min. The absorbance of the reagent drop is proportional to the sampling time and to the analyte concentration. The absorbance signal increases with increased sample gas flow until a maximum is reached then decreases until it forms a plateau. The proposed method was evaluated using both outdoor and indoor samples, and it was shown to viable provide an accurate measure of total aldehyde. |
publishDate |
2001 |
dc.date.none.fl_str_mv |
2001-08-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422001000400003 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422001000400003 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
10.1590/S0100-40422001000400003 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Química Nova v.24 n.4 2001 reponame:Química Nova (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Química Nova (Online) |
collection |
Química Nova (Online) |
repository.name.fl_str_mv |
Química Nova (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
quimicanova@sbq.org.br |
_version_ |
1750318102027960320 |