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Avaliação do potencial do pólen apícola como bioindicador de contaminação ambiental por agrotóxicos / Evaluation of potencial use of bee pollen as bioinidicator of environmental pesticide contaminationOliveira, Renata Cabrera de, 1984- 08 August 2014 (has links)
Orientadores: Susanne Rath, Sonia Claudia do Nascimento de Queiroz / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-26T03:44:24Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: O uso frequente e indiscriminado de agrotóxicos na agricultura tem acarretado a presença de resíduos nos alimentos e contaminação ambiental, principalmente em países com grande potencial agrícola, como o Brasil. Para avaliar a presença de resíduos de agrotóxicos no ambiente, as abelhas e os produtos apícolas têm sido apontados como potenciais bioindicadores, podendo ser utilizados para monitorar grandes áreas devido às longas distâncias percorridas. Assim sendo, o potencial do uso do pólen apícola como bioindicador da contaminação ambiental por agrotóxicos foi avaliado neste trabalho. Para isso, foi necessário desenvolver e validar um método analítico para determinação de multirresíduos em pólen apícola, utilizando cromatografia a gás acoplada à espectrometria de massas sequencial (GC-MS/MS). Para definição das condições ótimas de extração, dois processos foram avaliados: o QuEChERS, e o de partição com acetonitrila. O QuEChERS mostrou ser mais eficiente (melhor seletividade e eficiência de extração) e foi validado para a determinação de 27 agrotóxicos. Estudos de sorção mostraram que os agrotóxicos são fortemente sorvidos no pólen. Nas amostras provenientes do apiário experimental na Embrapa em Jaguariúna/SP não foram encontrados níveis quantificáveis dos agrotóxicos pesquisados, enquanto a presença de resíduos de agrotóxicos nas amostras fornecidas por apicultores de Ribeirão Preto/SP foi confirmada e quantificada. Os métodos desenvolvidos e validados mostraram ser eficientes e podem ser utilizados no monitoramento ambiental quanto à presença de resíduos de agrotóxicos. Os resultados confirmam o potencial do pólen apícola como bioindicador de contaminação ambiental por agrotóxicos / Abstract: The extensive use of pesticides in agriculture crop has led to the presence of residues in food and environmental contamination, especially in countries with great agricultural potential, such as Brazil. To assess the presence of pesticide residues in the environment, honeybees and bee products have been mentioned as potential bioindicators, which can be used to monitor large areas due to long distances travelled. Therefore, the potential use of bee pollen as a bioindicator of environmental pesticides contamination has been reported in this work. For this it was necessary to develop and validate an analytical method for the determination of multiresidues in pollen, using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). For the definition of optimum extraction conditions, two procedures were evaluated: QuEChERS, and partition with acetonitrile. The QuEChERS proved to be more efficient (improved selectivity and extraction efficiency), and was validated for the determination of 27 pesticides. Sorption studies showed that pesticides are strongly sorbed in pollen. Unquantifiable levels of pesticides surveyed were found in the samples from experimental apiary at Embrapa in Jaguariúna/SP, while the presence of pesticide residues in samples provided by apiarists from Ribeirão Preto/SP was confirmed and quantified. The validated analytical methods proved to be efficient and can be used in environmental monitoring for the presence of pesticide residues. The results confirm the potential of bee pollen as a bioindicator of environmental pesticides contamination / Doutorado / Quimica Analitica / Doutora em Ciências
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Application de la technique de thermodésorption pour l'analyse de 93 COV et le screening des COV dans l'air des lieux de travail / Application of thermodesorption technique to 93 VOC assay and screening of VOC in workplace airMaret, Laure 20 December 2013 (has links)
Aujourd'hui, la gestion du risque en milieu profesionnel ainsi que l'évaluation de l'exposition aux polluants, tels que les Composés Organiques Volatils (COV) présents dans l'air deviennent une nécessité tant la qualité de l'air des lieux de travail peut être à l'origine de problèmes de santé ou de maladies professionnelles reconnues. Dans le but de répondre à ces exigences de sécurité, l'Université Claude Bernard Lyon 1 a institutionnalisé et développé une Cellule Analyse Hygiène Sécurité et Environnement en lien direct avec le service SHS préexistant. Cette cellule est chargée de la mise en place d'une méthodologie de surveillance de la qualité de l'air intérieur de l'ensemble des locaux de l'université (14 sites, environ 80 laboratoires) en accord avec le code du travail et de l'environnement. Afin de pouvoir assurer l'ensemble des analyses inhérentes aux lieux de travail, le SHS a défini 45 composés comme prioritaires ajoutés à la liste du SHS et portent à 93 le nombre de COV identifiés et quantifiés. La méthode de séparation et d'identification mise en place permet d'atteindre des limites de quantification largement inférieures aux VLCT et VLEP 8 heures fixées par la législation. Des campagnes de prélèvement ont pu ainsi être organisées en collaboration avec le SHS et être lancées au sein de l'université / Over the past 10 years, indoor air quality has become a real Health and Safety concern, especialty in the workplace, which has led to the legislation proposal of concentrations guidelines for pollutants such as Volatiles Organic Compounds (VOC). To comply with the Safety requirements, The Claude Bernard University Lyon 1 has institutionalized and developed an Environment, Health and Safety Unit (HSE Unit), to provide the analyses for the Health and Safety team (SHS). This specialist unit has developed a supervision methodology to control the indoor air quality in all the buildings of the university, including all the 80 research and training laboratories. In order to carry out the assessment, the SHS team defined 45 compounds classified as priority, according to their threshold limit values (TLV-TWA or TLV-STEL) to the workers. To this list of 45 VOC another list containing 48 VOC is added. Evaluation of the trapping capacity of each sorbent, for a mix containing 93 VOC has been studied. Moreover, separation and identification methods were developed and optimized allowing to reach a quantification limit lower than professional limit value exposure. Using these methods and the results of the trapping comparisons, different applications were implemented, such as sampling campaigns in different laboratories
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New Chemometric Approaches to Non-targeted GCMS Fingerprinting Analysis of Wine Volatiles / Nouvelles approches par empreinte chromatographique non ciblées des composés volatiles du vinVestner, Jochen 13 September 2016 (has links)
Contrairement à l’analyse ciblée des composés volatils du vin par chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC-MS), les approches par GC-MS non ciblées prennent en compte les composés connus et inconnus. Ces méthodes sont plus rapides et fournissent une représentation plus complète de la composition de l’échantillon. Bien que plusieurs approches non-ciblées aient été développées, il y a encore une forte demande d’outils automatisés pour le traitement des données, en particulier pour les données multidimensionnelles complexes telles que celles de multiples chromatogrammes GC-MS. Ce travail visait à développer deux nouvelles approches chimiométriques pour l’analyse des données GC-MS non ciblées. Ces approches prennent en considération les décalages de temps de rétention entre les échantillons et rendent inutile l’intégration des pics. Elles ont été testées avec un jeu de données GC-MS simulées et un jeu de données GC-MS réelles d’échantillons de vin. De plus, l’une des deux approches GC-MS non ciblée a été combinée à la technique d’analyse sensorielle rapide de "projective mapping". Cette méthodologie a été utilisée pour étudier l’impact de la fermentation malolactique sur des vins issus du cépage Pinotage ainsi que l’effet de l’âge de la vigne, de la turbidité du moût et de la souche de levure sur l’arôme de vins de Riesling expérimentaux. / In contrast to targeted gas chromatography mass spectrometry (GC-MS) analysis of wine volatiles, non-targeted GC-MS approaches take information of known and unknown compounds into account, are faster, inherently more comprehensive and give a more holistic representation of the sample composition. Although several non-targeted approaches have been developed, there is still a great demand for automated data processing tools, especially for complex multi-way data such as chromatographic data obtained from multichannel detectors (e.g. GC-MS chromatograms of multiple samples). This work therefore aimed at the development of data processing procedures for non-targeted GC-MS analysis of volatile wine compounds. The two developed approaches use basic matrix manipulation of segmented GC-MS chromatograms and PCA or PARAFAC multi-way modelling. The approaches take retention time shifts between samples into account and avoid peak integration. A demonstration of the new fingerprinting approaches is presented using an artificial GC-MS data set and an experimental full-scan GC-MS data set obtained for a set of experimental wines. Results of the new approaches were also compared to a references method. Furthermore, the combination of one of the developed GC-MS fingerprinting approaches with the fast sensory screening technique projective mapping was exploited as a powerful approach to simultaneously study the volatile composition and the sensory characteristics of experimental wines. This methodology was used to study the impact of different malolactic fermentation scenarios on two different Pinotage wine styles and for a full factorial investigation of the impact of grape vine age, must turbidity and yeast strain on the aroma of Riesling experimental wines.
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Conyza canadensis : determinação de compostos bioativos e avaliação da atividade antifúngica / Conyza canadensis : determination of bioactive compounds and evaluation of antifungal activityPorto, Rafael Silveira, 1989- 27 August 2018 (has links)
Orientadores: Susanne Rath, Sonia Claudia do Nascimento de Queiroz / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-27T01:49:14Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: O Brasil é um dos maiores produtores de frutas do mundo, no entanto, estima-se que doenças pós-colheita possam gerar perdas de até 50% em sua produção. A forma mais comum de tratamento para essas doenças envolve a aplicação de fungicidas sintéticos. Contudo, nos últimos anos, a demanda por tratamentos alternativos tem crescido, com destaque para o uso de biopesticidas, produtos desenvolvidos a partir de plantas, microrganismos e insetos. Este trabalho teve como objetivo investigar a presença dos compostos bioativos (4Z)-lachnophyllum lactona, (4Z,8Z)-matricaria lactona e (2Z,8Z)-matricaria ester nos espécimes brasileiros da planta Conyza canadensis, bem como avaliar a atividade antifúngica dessas substâncias isoladas contra diversos fungos associados a doenças pós-colheita de frutas. Por cromatografia flash preparativa foi possível isolar a (4Z)-lachnophyllum lactona e a (4Z,8Z)-matricaria lactona a partir de extratos da planta obtidos com diclorometano. Os compostos foram caracterizados por GC-MS/MS, NMR 1H e 13C, 1H-1H COSY e 1H-13C HSQC. Foram realizados ensaios de difusão em disco com 10 fungos filamentosos causadores de doenças pós-colheita em frutas. Os fungos Aspergillus niger, Cladosporium spp. e Penicillium digitatum se mostraram susceptíveis ao tratamento e, para eles, a concentração mínima inibitória dos compostos variou de 32 a 64 µg mL-1. Também foi desenvolvido um método de extração empregando água quente pressurizada, no qual foram otimizados os parâmetros de temperatura (100 °C), tempo de ciclo (1 min) e número de ciclos (quatro). Com essa técnica foi possível obter um rendimento de 1,46 mg g-1 e 0,24 mg g-1 para a (4Z)-lachnophyllum lactona e a (4Z,8Z)-matricaria lactona, respectivamente. O extrato aquoso da Conyza canadensis pode ser aplicado diretamente nos frutos com a vantagem de não conter resíduos de solventes orgânicos tóxicos / Abstract: razil is one of the largest fruit producers in the world. Nevertheless, it is estimated that postharvest diseases can lead to losses of up to 50% in its production. The most common treatment for these diseases involves the application of synthetic fungicides. Nonetheless, in recent years, the demand for alternative treatments has increased, especially for the use of biopesticides, products developed from plants, microorganisms and insects. This study aimed to investigate the presence of the bioactive compounds (4Z)-lachnophyllum lactone, (4Z,8Z)-matricaria lactone and (2Z,8Z)-matricaria ester in Brazilian specimens of the weed Conyza canadensis, as well as to evaluate the antifungal activity of these isolated substances against several fungi associated with postharvest diseases of fruits. With the use of preparative flash chromatography it was possible to isolate (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone from plant extracts obtained with dichloromethane. The compounds were characterized by GC-MS/MS, NMR 1H e 13C, 1H-1H COSY and 1H-13C HSQC. Disk diffusion assays were performed in order to investigate the activity of the isolated compounds against 10 filamentous fungi regarded as common postharvest pathogens of fruits. Aspergillus niger, Cladosporium spp. and Penicillium digitatum proved susceptible to the treatment and, for them, the minimum inhibitory concentration of the compounds varied from 32 to 64 µg mL-1. An extraction method using pressurized hot water was also developed, in which the parameters of temperature (100 ° C), cycle time (1 min) and number of cycles (four) were optimized. By using this technique, it was possible to obtain a yield of 1.46 mg g-1 and 0.24 mg g-1 for the (4Z)-lachnophyllum lactone and (4Z,8Z)-matricaria lactone, respectively. The aqueous extract of Conyza canadensis can be applied directly on fruits with the advantage of not containing residues of toxic organic solvents / Mestrado / Quimica Analitica / Mestre em Química
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Exploring the Molecular Origin of Jet Fuel Thermal Oxidative Deposition Through Statistical Analysis of Mass Spectral Data and Pyrolysis Gas Chromatography/Mass Spectrometry of DepositsChristison, Krege Matthew 01 January 2019 (has links)
ASTM D3241 (Standard Test Method for Thermal Oxidation Stability of Aviation Turbine Fuels) measures the thermal oxidative stability of jet fuels under elevated temperature and pressure conditions. When jet fuels fail ASTM D3241, either at the refinery or in the distribution system, there can be supply disruptions and financial losses. Understanding the causes of poor thermal oxidative stability in jet fuels could help prevent or mitigate issues. In order to develop a deeper understanding of the molecular precursors that lead to ASTM D3241 failures, a number of analytical methodologies and data treatment techniques have been developed, applied, and reported here. Statistical analysis of LC/MS ESI data from jet fuels with varying thermal oxidative stabilities allows for the identification of molecules that are significant to ASTM D3241 failures. Differential statistical analysis of LC/MS ESI data from jet fuels before and after thermal oxidative stressing in a QCM reactor elucidates which significant molecules are being consumed during oxidation and which molecules are increasing in abundance. The analysis of thermal oxidative deposits that form during thermal oxidative stressing in the QCM reactor allows for the insight into the molecular components of the deposits. Attapulgus clay removes the polar molecules that lead to thermal oxidative stability issues in the refinery. Extraction of Attapulgus clay that has been used in a refinery to filter jet fuel with a series of solvents removes the polar molecules into a series of fractions. The subsequent analysis of the fractions by comprehensive GCxGC/MS leads to the identification of the different homologous series of molecules that are removed by the clay.
The analyses developed and employed here are shown to be particularly useful for the analysis of trace polar nitrogen and oxygen containing molecules. Similar homologous series of molecules are identified across all of the different analyses. It is also clear from some of the analyses, along with previously reported data in the literature, that reactive sulfur-containing molecules are significant to poor thermal oxidative stability as measured by ASTM D3241 and to the formation of thermal oxidative deposits. There is still an opportunity to find methodologies to better characterize the sulfur species present and correlate them to the data that is reported here.
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Untersuchungen zur Elektrochemischen Bodensanierung für die Stoffklasse der hochsiedenden aliphatischen ChlorkohlenwasserstoffeRöhrs, Joachim 09 January 2004 (has links) (PDF)
Die elektrokinetische Bodensanierung nutzt Transporteffekte aus, die entstehen, wenn ein elektrisches Feld an einen Bodenkörper angelegt wird. Die Sanierungsmethode versagt bei immobilen Schadstoffen. Allerdings scheint unter bestimmten Bedingungen ein im Boden induzierter Abbau der Schadstoffe möglich. Dafür müssen so genannte "Mikroleiter" und Redox-Systeme im Boden vorhanden sein. Hierzu werden theoretische Modelle vorgestellt. An einem konkreten Beispiel (mit aliphatischen Chlorkohlenwasserstoffen kontaminierter Boden) wurde getestet, ob direkt im Boden ein Abbau der Schadstoffe mit der Technik der elektrochemischen Bodensanierung erzielt werden kann. Die Analyse der CKW wurde per GC-MS durchgeführt. Theoretisch ist ein reduktiver Abbau oder eine Dechlorierung durch Eliminierungsreaktionen möglich. Die Ergebnisse der Laborversuche (Einwaage 100-3.000 g) erbrachten unter Einhaltung bestimmter Faktoren einen erfolgreichen Abbau der CKW. Bei ständiger Bewässerung des Bodens und einer Feldstärke von mindestens 600 V/m konnte ein Abbau festgestellt werden. Die Erhöhung des Chlorid-Gehaltes im Abwasser zeigt die erfolgreiche Abbaureaktion an. Potentielle Abbauprodukte mit weniger Chlor-Atomen im Molekülaufbau konnten nachgewiesen werden. Diese Stoffe lassen sich mit den ursprünglichen Kontaminationssubstanzen verknüpfen. Da eine Migration der Schadstoffe im elektrischen Feld nicht beobachtet wurde, wird eine im Boden induzierte Abbaureaktion angenommen. In Bodenzonen mit hohem pH-Wert (Eliminierung) und in Kathodennähe (Reduktion) waren die stärksten Abbauraten zu verzeichnen. Bei Versuchen ohne ständige Bewässerung war der CKW-Abbau schwach. Die Widerstände stiegen stark an. Ein Versuch in einem Container (Einwaage Boden: ca. 2 t) erbrachte nur einen punktuellen Abbau der CKW. Die Struktur des Originalbodens verhinderte den Aufbau eines homogenen elektrischen Feldes. In einem Fassversuch (Einwaage Boden: ca. 33 kg) wurden die Versuchsbedingungen modifiziert. Anlagerungen an allen Elektroden verhinderten eine ausreichend hohe effektive Feldstärke im Bodenkörper. Sanierungseffekte fanden nur lokal begrenzt statt. Im Vergleich von Labor zu Großversuchen zeigte sich, dass die eingetragene Ladungsmenge eine entscheidende Rolle spielt.
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Untersuchungen zur Elektrochemischen Bodensanierung für die Stoffklasse der hochsiedenden aliphatischen ChlorkohlenwasserstoffeRöhrs, Joachim 04 November 2003 (has links)
Die elektrokinetische Bodensanierung nutzt Transporteffekte aus, die entstehen, wenn ein elektrisches Feld an einen Bodenkörper angelegt wird. Die Sanierungsmethode versagt bei immobilen Schadstoffen. Allerdings scheint unter bestimmten Bedingungen ein im Boden induzierter Abbau der Schadstoffe möglich. Dafür müssen so genannte "Mikroleiter" und Redox-Systeme im Boden vorhanden sein. Hierzu werden theoretische Modelle vorgestellt. An einem konkreten Beispiel (mit aliphatischen Chlorkohlenwasserstoffen kontaminierter Boden) wurde getestet, ob direkt im Boden ein Abbau der Schadstoffe mit der Technik der elektrochemischen Bodensanierung erzielt werden kann. Die Analyse der CKW wurde per GC-MS durchgeführt. Theoretisch ist ein reduktiver Abbau oder eine Dechlorierung durch Eliminierungsreaktionen möglich. Die Ergebnisse der Laborversuche (Einwaage 100-3.000 g) erbrachten unter Einhaltung bestimmter Faktoren einen erfolgreichen Abbau der CKW. Bei ständiger Bewässerung des Bodens und einer Feldstärke von mindestens 600 V/m konnte ein Abbau festgestellt werden. Die Erhöhung des Chlorid-Gehaltes im Abwasser zeigt die erfolgreiche Abbaureaktion an. Potentielle Abbauprodukte mit weniger Chlor-Atomen im Molekülaufbau konnten nachgewiesen werden. Diese Stoffe lassen sich mit den ursprünglichen Kontaminationssubstanzen verknüpfen. Da eine Migration der Schadstoffe im elektrischen Feld nicht beobachtet wurde, wird eine im Boden induzierte Abbaureaktion angenommen. In Bodenzonen mit hohem pH-Wert (Eliminierung) und in Kathodennähe (Reduktion) waren die stärksten Abbauraten zu verzeichnen. Bei Versuchen ohne ständige Bewässerung war der CKW-Abbau schwach. Die Widerstände stiegen stark an. Ein Versuch in einem Container (Einwaage Boden: ca. 2 t) erbrachte nur einen punktuellen Abbau der CKW. Die Struktur des Originalbodens verhinderte den Aufbau eines homogenen elektrischen Feldes. In einem Fassversuch (Einwaage Boden: ca. 33 kg) wurden die Versuchsbedingungen modifiziert. Anlagerungen an allen Elektroden verhinderten eine ausreichend hohe effektive Feldstärke im Bodenkörper. Sanierungseffekte fanden nur lokal begrenzt statt. Im Vergleich von Labor zu Großversuchen zeigte sich, dass die eingetragene Ladungsmenge eine entscheidende Rolle spielt.
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Analytical studies of organic emissions from anthropogenic and natural sourcesMcCaffrey, Carol Anne January 1996 (has links)
No description available.
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Novel Solid-Phase Extraction Techniques for Biological and Environmental Analysis Using Isotope Dilution Mass SpectrometryBoggess, Andrew 18 May 2016 (has links)
Awareness and study of the ways in which the environment can interact with the personal genetics and epigenetics of an individual has grown substantially in recent years, resulting in the field of Exposomics. In an era of increasingly personalized medicine, novel techniques are necessary to ensure the accurate and sensitivity measurement of clinically and environmentally relevant molecules in biological and environmental samples. Addressing existing shortcomings cited in literature, methods were developed and optimized for the extraction, separation, mass analysis, and quantification of a suite of environmental organic pollutants in both biological and environmental samples, with the primary objective of improving accuracy, increasing sensitivity, and reducing sample and reagent consumption. The secondary objective of this research was the production of validated methods capable of inter-laboratory method transfer with minimal training required in the receiving laboratory. Two novel methods have been developed, optimized, validated, and applied to collaborative environmental research. These novel methods represented a demonstrative improvement upon existing methods in both analytical quality and capability for inter-laboratory method transfer. Both developed methods were utilized in two collaborative clinical research studies investigating the impact of environmentally-sources agents on children diagnosed with autism spectrum disorders (ASD). The high-quality data obtained in these studies yielded results that may have provided valuable insight into the development and maintenance of autism spectrum disorders. These novel methods allowed for the discovery of a first-of-its-kind variable in the children with ASD, compared with controls. This variable was statistically predictive for the probability of an individual being diagnosed with the most behaviorally severe autism disorder, with a statistically significant overall model fit. This novel analytical method was then expanded in breadth through application to industrial and municipal wastewater to aid in updating EPA Method 625 for wastewater analysis. Applying this novel method to wastewater produced data of higher analytical quality, in both accuracy and precision, compared with all other collaborative laboratories. The methods developed in this work for the quantification of organic molecules implicated in environmental human health in biological and environmental samples have significantly improved analytically upon existing methods and have yielded clinically relevant findings in collaborative clinical research studies. / Bayer School of Natural and Environmental Sciences; / Chemistry and Biochemistry / PhD; / Dissertation;
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Application of Solid Phase Micro-Extraction (SPME) - GC-MS for Identifying Pyrolysis Compounds in TextilesBradford, Brock 20 September 2016 (has links)
This thesis project describes research using headspace solid phase micro-extraction with gas chromatography (HS-SPME GC-MS) as an analytical tool for assessing textile fibres. It was found that this method required a temperature of >500oC to pyrolize the textile sample. A total of 5 minutes was determined to be the optimal time for collecting the volatile analytes. Numerous analytes were found to be chemical markers for each of the individual textile fibres.
The chemical markers are qualitatively used to describe each textile uniquely, and it was found that by using the chromatographic patterns, the textiles could be identified individually and in mixtures containing two textiles.
Lastly, by accelerating the age of the textile fibres by means of heat, ultra-violet light, and humidity, a comparison was made between the un-aged and aged fibres. It was found that each of the techniques arose different results and in some cases new compounds. / October 2016
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