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Carin Muhlen

UERJ - Universidade do Estado do Rio de Janeiro / Rio de Janeiro State University, DEQA, Adjunct

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Associate professor at the University of Rio de Janeiro State in the Faculty of Technology (FAT-ERJ) in Resende RJ, coordinator of the Centre for Development and Technological Innovation George Eastman - CDIT , permanent professor at Doctorate in Environmental Engeneering - DEAMB, Director of Water Centre and Coordinator of the Permanent Technical Chamber of Management and Legal Instruments of the Watershed Committee of the Middle Paraiba do Sul region.

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Bruno Spinosa de Martinis

Alexandre Chida

Perola Castro Vasconcellos

CHAVES, H . A . F.

State University of Rio de Janeiro

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Papers by Carin Muhlen

Caracterização cromatográfica de compostos orgânicos presentes nos resíduos sólidos provenientes de indústria de reciclagem de papel e sua aplicação na produção de briquetes de carvão vegetal

Química Nova, 2011

Recebido em 7/1/11; aceito em 12/4/11; publicado na web em 29/6/11 CHROMATOGRAPHIC CHARACTERIZATI... more Recebido em 7/1/11; aceito em 12/4/11; publicado na web em 29/6/11 CHROMATOGRAPHIC CHARACTERIZATION OF ORGANIC COMPOUNDS DERIVING FROM SOLID RESIDUES OF RECYCLE PAPER INDUSTRY AND ITS APPLICATIONS TO VEGETABLE CHARCOAL BRIKET PRODUCTION. Recycling of paper in industrial scale has become an established practice worldwide. In this work, organic compositions of three different kinds of sludge generated in recycle paper industry were studied, and the incorporation of one of those sludge in briket was also investigated. The characterization of organic compounds in sludge samples and briket was performed using Gas Chromatography coupled with Mass Spectrometry after a Soxhlet extraction. Different chemical classes were identified in each type of sludge, but just the sludge composed by cellulose residue did not presented polyaromatic hydrocarbons. Four formulations of sludge incorporated with charcoal for briket production were evaluated.

Endocrine disruptors in water filters used in the Rio dos Sinos Basin region, Southern Brazil

Brazilian Journal of Biology, 2015

The activated carbon filter is used in residences as another step in the treatment of drinking wa... more The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs) are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were an...

Índices De Retenção Em Cromatografia Gasosa Bidimensional Abrangente

Estimativa do número de amostras de solo para caracterizar elementos químicos utilizando fluorescência de raios X portátil em áreas contaminadas: estudo de caso em Resende

Engenharia Sanitaria e Ambiental

RESUMO A representatividade da amostragem é fundamental para embasar a tomada de decisão, uma vez... more RESUMO A representatividade da amostragem é fundamental para embasar a tomada de decisão, uma vez que a heterogeneidade da matriz é o principal fator para incerteza dos dados nos estudos de gerenciamento de áreas contaminadas. Neste estudo, coletaram-se 112 amostras de solo superficial em malha quadrada de 1 x 1 m, em uma área 15 x 6 m, no campus regional de Resende da Universidade do Estado do Rio de Janeiro. Anteriormente, no terreno funcionaram empresas de produção de filmes radiográficos e purificação de prata metálica. As amostras de solo foram analisadas por pXRF, método de screening para metais. Com base nos dados levantados, calculou-se, por meio de métodos estatísticos, a quantidade de amostras que permitiriam uma caracterização representativa da área, considerando um erro relativo de 20% para dois intervalos de confiança: 95 e 80%. As análises indicaram concentrações superiores aos valores de referência para os parâmetros prata, mercúrio, chumbo, selênio e zinco. Os result...

Compostos orgânicos em chorume

Caracterização química de compostos nitrogenados do petróleo brasileiro e de óleos voláteis de plantas brasileiras usando cromatografia bidimensional abrangente

Estudo de compostos orgânicos em lixiviado de aterros sanitários por EFS CG/EM

Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND... more Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND GC/MSD.The main purpose of this work was the qualitative study of organic compounds in landfill leachate. The samples were collected from a sanitary landfill located at Gravataí, a southern Brazilian city, that receive both, industrial and domestic refuse. The samples were submitted to solid phase extraction (SPE) with XAD-4 resin as the stationary phase. The instrumental analysis was performed by Gas Chromatography with a Mass Spectrometry Detector (GC/MSD). The compounds achieved in the SPE extracts were tentatively identified by the GC/MS library. It was found several oxygen and nitrogen compounds like carboxylic acids, ketones, amines and amides. Sulfur compounds and phthalate esters are also identified.

Application of comprehensive two-dimensional gas chromatography (GC×GC) in the characterization of biodiesel/diesel blends: application to beef tallow biodiesel

Quimica Nova, Dec 1, 2010

The growth of biodiesel market and the implementation of regulations related to biodiesel product... more The growth of biodiesel market and the implementation of regulations related to biodiesel production and biodiesel/diesel blending has encouraged the development of appropriate analytical methods to control the composition of this type of mixture. In this study, an evaluation of the potential of GC×GC for the characterization of samples of beef tallow biodiesel and the composition of blends of biodiesel/ diesel is presented. The methodology was applied to beef tallow biodiesel and its mixtures with petrodiesel, ranging from B2 to B50. Results allowed not only the identification and quantification of the biodiesel esters, but also the biodiesel percentage in biodiesel/ diesel blends.

MEFS : uma nova estratégia para monitoramento ambiental

Comparative study of Eucalyptus dunnii volatile oil composition using retention indices and comprehensive two-dimensional gas chromatography coupled to time-of-flight and quadrupole mass spectrometry

Journal of Chromatography a, Jul 18, 2008

In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied... more In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied using comprehensive two-dimensional gas chromatography (GC × GC) techniques. Structurally related compounds were found to elute mainly in specific regions of the two-dimensional space, showing orderly distribution with chemical class. Mass spectra of essential oil components were obtained from two different mass spectrometry detection methods: quadrupole (qMS) and time-of-flight (TOFMS), using the same GC × GC system under the same chromatographic conditions. Higher values of Similarity (average S of 914 with TOFMS compared to 880 with qMS) and Reverse (average R of 944 with TOFMS compared to 881 with qMS) were obtained with GC × GC/TOFMS showing its superior performance, which was most likely due to better sensitivity and resolution arising from the TOFMS system, and lack of spectral bias. Also, the number of compounds found in E. dunnii essential oil was 15% higher when TOFMS was used. Most of these are lower abundance components or exhibit low quality mass spectra; this supports the improved sensitivity obtained with TOFMS. A linear relationship (r 2 = 0.998) between experimental retention indices (LTPRI) of 30 standard compounds obtained with GC × GC/TOFMS and GC with flame ionization detection literature retention indices is reported as an aid for compound identification.

Chromatographic characterization of organic compounds deriving from solid residues of recycle paper industry and its applications to vegetable charcoal briket production

Química Nova

Recycling of paper in industrial scale has become an established practice worldwide. In this work... more Recycling of paper in industrial scale has become an established practice worldwide. In this work, organic compositions of three different kinds of sludge generated in recycle paper industry were studied, and the incorporation of one of those sludge in briket was also investigated. The characterization of organic compounds in sludge samples and briket was performed using Gas Chromatography coupled with Mass Spectrometry after a Soxhlet extraction. Different chemical classes were identified in each type of sludge, but just the sludge composed by cellulose residue did not presented polyaromatic hydrocarbons. Four formulations of sludge incorporated with charcoal for briket production were evaluated.

J Chromatogr A 1200 34 2008 dunnii1

In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied... more In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied using comprehensive two-dimensional gas chromatography (GC × GC) techniques. Structurally related compounds were found to elute mainly in specific regions of the two-dimensional space, showing orderly distribution with chemical class. Mass spectra of essential oil components were obtained from two different mass spectrometry detection methods: quadrupole (qMS) and time-of-flight (TOFMS), using the same GC × GC system under the same chromatographic conditions. Higher values of Similarity (average S of 914 with TOFMS compared to 880 with qMS) and Reverse (average R of 944 with TOFMS compared to 881 with qMS) were obtained with GC × GC/TOFMS showing its superior performance, which was most likely due to better sensitivity and resolution arising from the TOFMS system, and lack of spectral bias. Also, the number of compounds found in E. dunnii essential oil was 15% higher when TOFMS was used. Most of these are lower abundance components or exhibit low quality mass spectra; this supports the improved sensitivity obtained with TOFMS. A linear relationship (r 2 = 0.998) between experimental retention indices (LTPRI) of 30 standard compounds obtained with GC × GC/TOFMS and GC with flame ionization detection literature retention indices is reported as an aid for compound identification.

Estudo de compostos orgânicos em lixiviado de aterros sanitários por EFS e CG/EM

Química Nova, 2001

Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND... more Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND GC/MSD.The main purpose of this work was the qualitative study of organic compounds in landfill leachate. The samples were collected from a sanitary landfill located at Gravataí, a southern Brazilian city, that receive both, industrial and domestic refuse. The samples were submitted to solid phase extraction (SPE) with XAD-4 resin as the stationary phase. The instrumental analysis was performed by Gas Chromatography with a Mass Spectrometry Detector (GC/MSD). The compounds achieved in the SPE extracts were tentatively identified by the GC/MS library. It was found several oxygen and nitrogen compounds like carboxylic acids, ketones, amines and amides. Sulfur compounds and phthalate esters are also identified.

Caracterização de amostras petroquímicas e derivados utilizando cromatografia gasosa bidimensional abrangente (GCxGC)

Química Nova, 2006

Índices De Retenção Em Cromatografia Gasosa Bidimensional Abrangente

Scientia Chromatographica, 2009

Cromatografia unificada

Química Nova, 2004

Uso da cromatografia gasosa bidimensional abrangente (GC×GC) na caracterização de misturas biodiesel/diesel: aplicação ao biodiesel de sebo bovino

Química Nova, 2011

Nomenclatura na língua portuguesa em cromatografia multidimensional abrangente

Química Nova, 2007

Recebido em 26/10/05; aceito em 14/9/06; publicado na web em 7/2/07 NOMENCLATURE FOR COMPREHENSIV... more Recebido em 26/10/05; aceito em 14/9/06; publicado na web em 7/2/07 NOMENCLATURE FOR COMPREHENSIVE MULTIDIMENSIONAL CHROMATOGRAPHY IN PORTUGUESE LANGUAGE. Comprehensive Multidimensional Chromatography is a relatively new analytic technique, which is receiving growing attention in many parts of the world, including recently in Brazil. This work presents terms in Portuguese which are commonly used in Comprehensive Multidimensional Chromatography in order to help standardize the vocabulary employed in this area in the scientific literature. It also includes some symbols, their nominations, and explanation of some terms, whenever necessary. This proposal does not intend to be comprehensive or definitive; on the contrary, it intends to be a first step in the process of establishing a standardized nomenclature, serving as a base for a further sound discussion in the scientific community realm.

Qualitative and quantitative study of nitrogen-containing compounds in heavy gas oil using comprehensive two-dimensional gas chromatography with nitrogen phosphorus detection

Journal of Separation Science, 2007

Qualitative and quantitative study of nitrogencontaining compounds in heavy gas oil using compreh... more Qualitative and quantitative study of nitrogencontaining compounds in heavy gas oil using comprehensive two-dimensional gas chromatography with nitrogen phosphorus detection In this work, a GC6GC -nitrogen -phosphorus detection (NPD) methodology was developed to separate and quantitate nitrogen-containing compounds in Brazilian heavy gas oil. First, the NPD performance was improved in order to achieve best GC6GC performance. The geometry of this detector was also evaluated. The use of an extended jet improved significantly the peak shape. The GC6GC separation was studied using both first and second dimension columns with different internal diameters. The use of a thicker film in both dimensions provided better performance. LODs of 0.16 -8.49 pg of individual compounds were achieved. Two different extraction techniques of the neutral and basic nitrogen-containing compounds were also evaluated. The method using ion-exchange resins to separate neutral and basic nitrogen-containing compounds was more efficient than the method using modified silica. As an example, the amounts (lg/g) of each class reported were: indole (2.77), alkyl carbazoles ranging from C 0 to C 6+ (1.467), alkyl benzocarbazoles from C 0 to C 4+ (793), alkyl quinolines (31.2) and alkyl benzoquinolines (21.6) were quantitated.

Detector technologies for comprehensive two-dimensional gas chromatography

Journal of Separation Science, 2006

The detector is an integral and important part of any chromatographic system. The chromatographic... more The detector is an integral and important part of any chromatographic system. The chromatographic peak profiles (i. e. peak separation) should, ideally, be unaffected by the detector -it should only provide the sensing capacity required at the end of a column separation process. The relatively new technique of comprehensive 2-D GC (GC6GC) extends the performance of GC manyfold, but comes at a price -existing GC systems may not be adequately designed with the requirements of GC6GC in mind. This is primarily the need for precise measurement of very fast peaks entering the detector (e. g. as fast as 50 ms basewidth in some instances). The capacity of the detector to closely track a rapidly changing chromatographic peak profile depends on a number of factors, such as design of flow paths and make-up gas introduction, type of detector response mechanism, and the chemistry of the response. These factors are discussed here as a means to appreciate the technical demands of detection in GC6GC. The MS detector will not be included in this review.

Caracterização cromatográfica de compostos orgânicos presentes nos resíduos sólidos provenientes de indústria de reciclagem de papel e sua aplicação na produção de briquetes de carvão vegetal

Química Nova, 2011

Recebido em 7/1/11; aceito em 12/4/11; publicado na web em 29/6/11 CHROMATOGRAPHIC CHARACTERIZATI... more Recebido em 7/1/11; aceito em 12/4/11; publicado na web em 29/6/11 CHROMATOGRAPHIC CHARACTERIZATION OF ORGANIC COMPOUNDS DERIVING FROM SOLID RESIDUES OF RECYCLE PAPER INDUSTRY AND ITS APPLICATIONS TO VEGETABLE CHARCOAL BRIKET PRODUCTION. Recycling of paper in industrial scale has become an established practice worldwide. In this work, organic compositions of three different kinds of sludge generated in recycle paper industry were studied, and the incorporation of one of those sludge in briket was also investigated. The characterization of organic compounds in sludge samples and briket was performed using Gas Chromatography coupled with Mass Spectrometry after a Soxhlet extraction. Different chemical classes were identified in each type of sludge, but just the sludge composed by cellulose residue did not presented polyaromatic hydrocarbons. Four formulations of sludge incorporated with charcoal for briket production were evaluated.

Endocrine disruptors in water filters used in the Rio dos Sinos Basin region, Southern Brazil

Brazilian Journal of Biology, 2015

The activated carbon filter is used in residences as another step in the treatment of drinking wa... more The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs) are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were an...

Índices De Retenção Em Cromatografia Gasosa Bidimensional Abrangente

Estimativa do número de amostras de solo para caracterizar elementos químicos utilizando fluorescência de raios X portátil em áreas contaminadas: estudo de caso em Resende

Engenharia Sanitaria e Ambiental

RESUMO A representatividade da amostragem é fundamental para embasar a tomada de decisão, uma vez... more RESUMO A representatividade da amostragem é fundamental para embasar a tomada de decisão, uma vez que a heterogeneidade da matriz é o principal fator para incerteza dos dados nos estudos de gerenciamento de áreas contaminadas. Neste estudo, coletaram-se 112 amostras de solo superficial em malha quadrada de 1 x 1 m, em uma área 15 x 6 m, no campus regional de Resende da Universidade do Estado do Rio de Janeiro. Anteriormente, no terreno funcionaram empresas de produção de filmes radiográficos e purificação de prata metálica. As amostras de solo foram analisadas por pXRF, método de screening para metais. Com base nos dados levantados, calculou-se, por meio de métodos estatísticos, a quantidade de amostras que permitiriam uma caracterização representativa da área, considerando um erro relativo de 20% para dois intervalos de confiança: 95 e 80%. As análises indicaram concentrações superiores aos valores de referência para os parâmetros prata, mercúrio, chumbo, selênio e zinco. Os result...

Compostos orgânicos em chorume

Caracterização química de compostos nitrogenados do petróleo brasileiro e de óleos voláteis de plantas brasileiras usando cromatografia bidimensional abrangente

Estudo de compostos orgânicos em lixiviado de aterros sanitários por EFS CG/EM

Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND... more Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND GC/MSD.The main purpose of this work was the qualitative study of organic compounds in landfill leachate. The samples were collected from a sanitary landfill located at Gravataí, a southern Brazilian city, that receive both, industrial and domestic refuse. The samples were submitted to solid phase extraction (SPE) with XAD-4 resin as the stationary phase. The instrumental analysis was performed by Gas Chromatography with a Mass Spectrometry Detector (GC/MSD). The compounds achieved in the SPE extracts were tentatively identified by the GC/MS library. It was found several oxygen and nitrogen compounds like carboxylic acids, ketones, amines and amides. Sulfur compounds and phthalate esters are also identified.

Application of comprehensive two-dimensional gas chromatography (GC×GC) in the characterization of biodiesel/diesel blends: application to beef tallow biodiesel

Quimica Nova, Dec 1, 2010

The growth of biodiesel market and the implementation of regulations related to biodiesel product... more The growth of biodiesel market and the implementation of regulations related to biodiesel production and biodiesel/diesel blending has encouraged the development of appropriate analytical methods to control the composition of this type of mixture. In this study, an evaluation of the potential of GC×GC for the characterization of samples of beef tallow biodiesel and the composition of blends of biodiesel/ diesel is presented. The methodology was applied to beef tallow biodiesel and its mixtures with petrodiesel, ranging from B2 to B50. Results allowed not only the identification and quantification of the biodiesel esters, but also the biodiesel percentage in biodiesel/ diesel blends.

MEFS : uma nova estratégia para monitoramento ambiental

Comparative study of Eucalyptus dunnii volatile oil composition using retention indices and comprehensive two-dimensional gas chromatography coupled to time-of-flight and quadrupole mass spectrometry

Journal of Chromatography a, Jul 18, 2008

In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied... more In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied using comprehensive two-dimensional gas chromatography (GC × GC) techniques. Structurally related compounds were found to elute mainly in specific regions of the two-dimensional space, showing orderly distribution with chemical class. Mass spectra of essential oil components were obtained from two different mass spectrometry detection methods: quadrupole (qMS) and time-of-flight (TOFMS), using the same GC × GC system under the same chromatographic conditions. Higher values of Similarity (average S of 914 with TOFMS compared to 880 with qMS) and Reverse (average R of 944 with TOFMS compared to 881 with qMS) were obtained with GC × GC/TOFMS showing its superior performance, which was most likely due to better sensitivity and resolution arising from the TOFMS system, and lack of spectral bias. Also, the number of compounds found in E. dunnii essential oil was 15% higher when TOFMS was used. Most of these are lower abundance components or exhibit low quality mass spectra; this supports the improved sensitivity obtained with TOFMS. A linear relationship (r 2 = 0.998) between experimental retention indices (LTPRI) of 30 standard compounds obtained with GC × GC/TOFMS and GC with flame ionization detection literature retention indices is reported as an aid for compound identification.

Chromatographic characterization of organic compounds deriving from solid residues of recycle paper industry and its applications to vegetable charcoal briket production

Química Nova

Recycling of paper in industrial scale has become an established practice worldwide. In this work... more Recycling of paper in industrial scale has become an established practice worldwide. In this work, organic compositions of three different kinds of sludge generated in recycle paper industry were studied, and the incorporation of one of those sludge in briket was also investigated. The characterization of organic compounds in sludge samples and briket was performed using Gas Chromatography coupled with Mass Spectrometry after a Soxhlet extraction. Different chemical classes were identified in each type of sludge, but just the sludge composed by cellulose residue did not presented polyaromatic hydrocarbons. Four formulations of sludge incorporated with charcoal for briket production were evaluated.

J Chromatogr A 1200 34 2008 dunnii1

In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied... more In the present work, the composition of volatile oil from leaves of Eucalyptus dunnii was studied using comprehensive two-dimensional gas chromatography (GC × GC) techniques. Structurally related compounds were found to elute mainly in specific regions of the two-dimensional space, showing orderly distribution with chemical class. Mass spectra of essential oil components were obtained from two different mass spectrometry detection methods: quadrupole (qMS) and time-of-flight (TOFMS), using the same GC × GC system under the same chromatographic conditions. Higher values of Similarity (average S of 914 with TOFMS compared to 880 with qMS) and Reverse (average R of 944 with TOFMS compared to 881 with qMS) were obtained with GC × GC/TOFMS showing its superior performance, which was most likely due to better sensitivity and resolution arising from the TOFMS system, and lack of spectral bias. Also, the number of compounds found in E. dunnii essential oil was 15% higher when TOFMS was used. Most of these are lower abundance components or exhibit low quality mass spectra; this supports the improved sensitivity obtained with TOFMS. A linear relationship (r 2 = 0.998) between experimental retention indices (LTPRI) of 30 standard compounds obtained with GC × GC/TOFMS and GC with flame ionization detection literature retention indices is reported as an aid for compound identification.

Estudo de compostos orgânicos em lixiviado de aterros sanitários por EFS e CG/EM

Química Nova, 2001

Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND... more Recebido em 1/6/00; aceito em 14/12/00 STUDY OF ORGANIC COMPOUNDS IN LANDFILL LEACHATE BY SPE AND GC/MSD.The main purpose of this work was the qualitative study of organic compounds in landfill leachate. The samples were collected from a sanitary landfill located at Gravataí, a southern Brazilian city, that receive both, industrial and domestic refuse. The samples were submitted to solid phase extraction (SPE) with XAD-4 resin as the stationary phase. The instrumental analysis was performed by Gas Chromatography with a Mass Spectrometry Detector (GC/MSD). The compounds achieved in the SPE extracts were tentatively identified by the GC/MS library. It was found several oxygen and nitrogen compounds like carboxylic acids, ketones, amines and amides. Sulfur compounds and phthalate esters are also identified.

Caracterização de amostras petroquímicas e derivados utilizando cromatografia gasosa bidimensional abrangente (GCxGC)

Química Nova, 2006

Índices De Retenção Em Cromatografia Gasosa Bidimensional Abrangente

Scientia Chromatographica, 2009

Cromatografia unificada

Química Nova, 2004

Uso da cromatografia gasosa bidimensional abrangente (GC×GC) na caracterização de misturas biodiesel/diesel: aplicação ao biodiesel de sebo bovino

Química Nova, 2011

Nomenclatura na língua portuguesa em cromatografia multidimensional abrangente

Química Nova, 2007

Recebido em 26/10/05; aceito em 14/9/06; publicado na web em 7/2/07 NOMENCLATURE FOR COMPREHENSIV... more Recebido em 26/10/05; aceito em 14/9/06; publicado na web em 7/2/07 NOMENCLATURE FOR COMPREHENSIVE MULTIDIMENSIONAL CHROMATOGRAPHY IN PORTUGUESE LANGUAGE. Comprehensive Multidimensional Chromatography is a relatively new analytic technique, which is receiving growing attention in many parts of the world, including recently in Brazil. This work presents terms in Portuguese which are commonly used in Comprehensive Multidimensional Chromatography in order to help standardize the vocabulary employed in this area in the scientific literature. It also includes some symbols, their nominations, and explanation of some terms, whenever necessary. This proposal does not intend to be comprehensive or definitive; on the contrary, it intends to be a first step in the process of establishing a standardized nomenclature, serving as a base for a further sound discussion in the scientific community realm.

Qualitative and quantitative study of nitrogen-containing compounds in heavy gas oil using comprehensive two-dimensional gas chromatography with nitrogen phosphorus detection

Journal of Separation Science, 2007

Qualitative and quantitative study of nitrogencontaining compounds in heavy gas oil using compreh... more Qualitative and quantitative study of nitrogencontaining compounds in heavy gas oil using comprehensive two-dimensional gas chromatography with nitrogen phosphorus detection In this work, a GC6GC -nitrogen -phosphorus detection (NPD) methodology was developed to separate and quantitate nitrogen-containing compounds in Brazilian heavy gas oil. First, the NPD performance was improved in order to achieve best GC6GC performance. The geometry of this detector was also evaluated. The use of an extended jet improved significantly the peak shape. The GC6GC separation was studied using both first and second dimension columns with different internal diameters. The use of a thicker film in both dimensions provided better performance. LODs of 0.16 -8.49 pg of individual compounds were achieved. Two different extraction techniques of the neutral and basic nitrogen-containing compounds were also evaluated. The method using ion-exchange resins to separate neutral and basic nitrogen-containing compounds was more efficient than the method using modified silica. As an example, the amounts (lg/g) of each class reported were: indole (2.77), alkyl carbazoles ranging from C 0 to C 6+ (1.467), alkyl benzocarbazoles from C 0 to C 4+ (793), alkyl quinolines (31.2) and alkyl benzoquinolines (21.6) were quantitated.

Detector technologies for comprehensive two-dimensional gas chromatography

Journal of Separation Science, 2006

The detector is an integral and important part of any chromatographic system. The chromatographic... more The detector is an integral and important part of any chromatographic system. The chromatographic peak profiles (i. e. peak separation) should, ideally, be unaffected by the detector -it should only provide the sensing capacity required at the end of a column separation process. The relatively new technique of comprehensive 2-D GC (GC6GC) extends the performance of GC manyfold, but comes at a price -existing GC systems may not be adequately designed with the requirements of GC6GC in mind. This is primarily the need for precise measurement of very fast peaks entering the detector (e. g. as fast as 50 ms basewidth in some instances). The capacity of the detector to closely track a rapidly changing chromatographic peak profile depends on a number of factors, such as design of flow paths and make-up gas introduction, type of detector response mechanism, and the chemistry of the response. These factors are discussed here as a means to appreciate the technical demands of detection in GC6GC. The MS detector will not be included in this review.