Air analysis by gas chromatography

Helmig, Detlev

doi:10.1016/s0021-9673(99)00173-9

Cited by 107 publications

(46 citation statements)

References 165 publications

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“…The use of cartridges using Tenax-TA as a sorbent material for measurements of certain BVOC requires significant care (e.g., Helmig, 1997Helmig, , 1999Komenda et al, 2001). On the other hand, with adequate quality control, cartridges can be an excellent way to trap these molecules of interest as they offer a convenient way of sample storage and are easy to use.…”

Section: Theory Of Operationmentioning

confidence: 99%

A disjunct eddy accumulation system for the measurement of BVOC fluxes: instrument characterizations and field deployment

et al. 2012

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Abstract. Biological volatile organic compounds (BVOCs), such as isoprene and monoterpenes, are emitted in large amounts from forests. Quantification of the flux of BVOCs is critical in the evaluation of the impact of these compounds on the concentrations of atmospheric oxidants and on the production of secondary organic aerosol. A disjunct eddy accumulation (DEA) sampler system was constructed for the measurement of speciated BVOC fluxes. Unlike traditional eddy covariance (EC), the relatively new technique of disjunct sampling differs by taking short, discrete samples that allow for slower sampling frequencies. Disjunct sample airflow is directed into cartridges containing sorbent materials at sampling rates proportional to the magnitude of the vertical wind. Compounds accumulated on the cartridges are then quantified by thermal desorption and gas chromatography. Herein, we describe our initial tests to evaluate the disjunct sampler including the application of vertical wind measurements to create optimized sampling thresholds. Measurements of BVOC fluxes obtained from DEA during its deployment above a mixed hardwood forest at the University of Michigan Biological Station (Pellston, MI) during the 2009 CABINEX field campaign are reported. Daytime (09:00 a.m. to 05:00 p.m. LT) isoprene fluxes, when averaged over the footprint of the tower, were 1.31 mg m −2 h −1 which are comparable to previous flux measurements at this location. Speciated monoterpene fluxes are some of the first to be reported from this site. Daytime averages were 26.7 µg m −2 h −1 for α-pinene and 10.6 µg m −2 h −1 for β-pinene. These measured concentrations and fluxes were compared to the output of an atmospheric chemistry model, and were found to be consistent with our knowledge of the variables that control BVOCs fluxes at this site.

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Section: Theory Of Operationmentioning

confidence: 99%

A disjunct eddy accumulation system for the measurement of BVOC fluxes: instrument characterizations and field deployment

et al. 2012

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“…In light of the analytical procedure and analyte matrix, a number of different stationary phases have been used by different authors. A polydimethylmethylsiloxane capillary column with 5% phenylmethylsiloxane (as stationary phase) has been used for the separation of CC-PFPH derivatives (Helmig, 1999). If we select columns in this respect, their polarity increases on the order: HP-1 (Rivero and Topiwala, 2004), b HP-5MS (Chien andYin, 2009), bHP-5 (Pang et al, 2011;Suliman, 2002), bDB-VRX (Kim and Pal, 2010).…”

Section: Elution Pattern and Solvent Effect On Chromatographic Separamentioning

confidence: 99%

The effect of solvent selection in the gas chromatographic analysis of carbonyls in air samples after derivatization with pentafluorophenyl hydrazine

Ullah

Kim

Szulejko

2015

Atmospheric Research

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“…Ainda, a fase estacionária deve possuir características similares (compatibilidade) à natureza química dos compostos que se deseja analisar. A avaliação de substâncias mais polares deve prever o uso de colunas cromatográficas mais polares, ao passo que a avaliação de COV, por exemplo, exige o uso de colunas apolares ou com polaridade muito baixa (HELMIG, 1999;SANTOS e GALCERAN, 2002;SCHIRMER, 2004).…”

Section: Análise De Gases Orgânicosunclassified

Os biocombustíveis no Brasil: panorama atual, emissões gasosas e os métodos analíticos de monitoramento da qualidade do ar referente a gases de natureza orgânica / Biofuels in Brazil: the current scene, gaseous emissions and analytical methods on air quality monitoring concerned to organic gases

Schirmer¹,

Gauer

2012

Ambiência

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ResumoA diminuição das reservas de petróleo, aliada às oscilações de seu preço e à pressão pela preservação do meio ambiente, evidenciam a necessidade de se diversificar a matriz energética mundial, por meio do uso de combustíveis renováveis. Grande parte da literatura referente a esse tema reporta, de fato, a redução significativa da grande maioria dos principais poluentes atmosféricos regulamentados. O presente trabalho aborda uma revisão do panorama dos biocombustíveis no Brasil (com ênfase no biodiesel), de modo sucinto, enfatizando os ganhos ambientais ao se substituir a matriz energética atual (predominantemente de origem fóssil), por combustíveis renováveis de origem vegetal. Traz ainda as principais técnicas de monitoramento no que se refere à amostragem e análise de gases orgânicos (especialmente compostos orgânicos voláteis), uma vez que compostos dessa natureza figuram entre os maiores poluentes do ar. Semelhantemente ao que se observa em âmbito internacional, a expectativa é de que, também no Brasil, ocorra um aumento no controle de fontes de poluentes dessa natureza, como a adoção de padrões de emissão mais rígidos (específicos para fontes de diferentes naturezas) e a inclusão de um programa de medida e controle/abatimento desses poluentes.Palavras-chave: biocombustíveis; biodiesel; monitoramento ambiental; qualidade do ar.

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Air analysis by gas chromatography

Cited by 107 publications

References 165 publications

A disjunct eddy accumulation system for the measurement of BVOC fluxes: instrument characterizations and field deployment

A disjunct eddy accumulation system for the measurement of BVOC fluxes: instrument characterizations and field deployment

The effect of solvent selection in the gas chromatographic analysis of carbonyls in air samples after derivatization with pentafluorophenyl hydrazine

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