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Emissões de N2 e N2O provenientes do fertilizante aplicado a solos cultivados com cana-de-açúcar pelo método do traçador 15N / N2 and N2O emissions from fertilizer applied on soil cultivated with sugarcane measured by 15N tracer methodMilagres, João José de Miranda 29 August 2014 (has links)
Emissões de N2 e N2O reduzem a eficiência da adubação e podem causar danos ambientais. O método do traçador isotópico (15N) é indicado para medições de N2 e N2O, masnão há relatos de sua utilização no Brasil na quantificação desses gases.O objetivo deste estudo foi adaptar o método do traçador 15N às condições brasileiras para quantificar N2 e N2O derivados do fertilizante aplicado à cana-de-açúcar. Para o ajuste do métodoforam conduzidos três experimentos: um em condições controladas e dois em condições de campo. Em ambiente controlado foram utilizados três solos com diferentes classes texturais. A influência da umidade (40, 60 e 80% da capacidade máxima de retenção de água - CMRA) e da adição ou não de dextrose (500 mgkg-1 de C), foram outros parâmetros avaliados. O K15NO3enriquecido em 23,24% em átomos de 15N foi a fonte de N (100 mg kg-1 de N) utilizada. Os trabalhos de campo foram realizados em Latossolo Vermelho da região de Piracicaba-SP, em área de canade- açúcar sem despalha a fogo. No segundo experimento, foram testadas: fontes de N (15ureia e 15NH4 15NO3, ambos com 31,9% em átomos de 15N); doses de N (55 e 110 kg ha-1); com e sem vinhaça (100 m3 ha-1). No terceiro foram testadas doses de N (70 e 140 kg ha-1)na forma de 15NH4 15NO3; doses de vinhaça (75 e 150 m3 ha-1); com e sem a cobertura de palha (11 Mg ha-1). Em cada experimento, buscou-se aprimorar o protocolo de coleta, preparo e análise dos gases. No primeiro experimento observou-se que somente tratamentos com dextrose emitiram N2O, sendo as emissões aumentadas com a elevação da CMRA de 40 para 60%.Perdas de N (N2 + N2O) do K15NO3variaram de 0,04 a 48,26%. No segundo experimento não foram observadas emissões nos tratamentos com 15ureia. Nos tratamentos com 15NH4 15NO3, somente N2O foi detectado.A vinhaça potencializou as emissões de N2O, mas os fatores de emissão ficaram abaixo de 0,4%. A não detecção do N2 levantou a hipótese que o enriquecimento isotópico dos fertilizantes foi insuficiente para marcar o N2 do interior das câmaras. Então, no último experimento, utilizou-se o 15NH4 15NO3enriquecido a 98 e a 10,43% para as determinações de N2 e N2O, respectivamente. Neste experimento a manutenção da palha intensificou as emissões de N2O proveniente do 15NH4 15NO3; a umidade, a temperatura, o Nmineral e o C-lábil do solo não apresentaram correlações significativas com emissões de N2O. Os fatores de emissão foram inferiores a 0,2%. No último experimento, também não foi detectado o N2, sugerindo que o N2O tenha sido o produto final da desnitrificação nos experimentos de campo. Os resultados mostraram que as adaptações realizadas no método do traçador 15N foram eficazes para a quantificação dos gases. Outras adaptações, entretanto, deverão surgir à medida que a adoção do método do traçador 15N se intensifique no Brasil / N2 and N2O emissions decrease the fertilization efficiency and can cause environmental damages. The 15N tracer method is used to measure N2 and N2O emissions, but there are no reports of its application in Brazil. The objective of the present study was to adapt the 15N tracer method to Brazilian conditions to quantify the N2 and N2O from fertilizers applied in sugarcane crop. Three experiments were conducted to adjusting the method: one in controlled conditions and the others in field. In controlled conditions, three soils with distinct textural class were evaluated. It was measured the moisture content (40, 60 and 80 % of water holding capacity - CMRA) and two levels of dextrose (0 and 500 mg C kg-1). K15NO3 (23.24 atom% 15N) was the N source used (100 mg kg-1). The field experiments were carried out on a RhodicDystrudox in Piracicaba region, Sao Paulo state. In the second experiment, two N sources (urea and NH4NO3, both with 31.9 atom% 15N), two N levels (55 and 110 kg ha-1) and two vinasse addition levels (0 and 100 m³ ha-1) were evaluated. In the third experiment, two N levels (70 and 140 kg ha-1) using 15NH4 15NO3 as N source, two vinasse levels (75 and 150 m³ ha-1) and the presence (11 Mg ha-1) or not of straw covering were evaluated. In each experiment, we try to improve our sampling protocol, gases preparing and analysis based on the limitations detected. In the first experiment, the N2O emissions occurred only in dextrose presence and were increased when the CMRA was raised to 60%. The N losses (N2+N2O) from K15NO3 varied from 0.04 to 48.26%. In the second experiment, it was not observed N2O emission with urea fertilization. In the treatments with NH4NO3 fertilization, it was only observed N2O emission. The vinasse application potentiated the N2O emissions, but the emissions factors were below 0.4 %. We believed that fertilizer isotopic enrichment was not sufficient to label the N2 inside chambers and because of this it was not possible measure N2 emission. So, in the last experiment, we used the 15NH4 15NO3 enriched with 98 and 10.43 atom% 15N to measure the N2 and N2O emission, respectively. In the same experiment, the straw maintenance on soil surface increased the N2O emissions from NH4NO3. The moisture, temperature, N-mineral and the C-labile were not significantly correlated with N2O emissions. The emissions factors were under of 0.2%. In the last experiment, likewise, it was not detected N2 emission, suggesting that the final product from denitrification was N2O in field experiments. Our results showed that adaptations realized in 15N tracer method were effective to quantify gases emissions. However, others adaptations can arise as result of intensification in adoption of 15N tracer method in Brazil
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Emissões de N2 e N2O provenientes do fertilizante aplicado a solos cultivados com cana-de-açúcar pelo método do traçador 15N / N2 and N2O emissions from fertilizer applied on soil cultivated with sugarcane measured by 15N tracer methodJoão José de Miranda Milagres 29 August 2014 (has links)
Emissões de N2 e N2O reduzem a eficiência da adubação e podem causar danos ambientais. O método do traçador isotópico (15N) é indicado para medições de N2 e N2O, masnão há relatos de sua utilização no Brasil na quantificação desses gases.O objetivo deste estudo foi adaptar o método do traçador 15N às condições brasileiras para quantificar N2 e N2O derivados do fertilizante aplicado à cana-de-açúcar. Para o ajuste do métodoforam conduzidos três experimentos: um em condições controladas e dois em condições de campo. Em ambiente controlado foram utilizados três solos com diferentes classes texturais. A influência da umidade (40, 60 e 80% da capacidade máxima de retenção de água - CMRA) e da adição ou não de dextrose (500 mgkg-1 de C), foram outros parâmetros avaliados. O K15NO3enriquecido em 23,24% em átomos de 15N foi a fonte de N (100 mg kg-1 de N) utilizada. Os trabalhos de campo foram realizados em Latossolo Vermelho da região de Piracicaba-SP, em área de canade- açúcar sem despalha a fogo. No segundo experimento, foram testadas: fontes de N (15ureia e 15NH4 15NO3, ambos com 31,9% em átomos de 15N); doses de N (55 e 110 kg ha-1); com e sem vinhaça (100 m3 ha-1). No terceiro foram testadas doses de N (70 e 140 kg ha-1)na forma de 15NH4 15NO3; doses de vinhaça (75 e 150 m3 ha-1); com e sem a cobertura de palha (11 Mg ha-1). Em cada experimento, buscou-se aprimorar o protocolo de coleta, preparo e análise dos gases. No primeiro experimento observou-se que somente tratamentos com dextrose emitiram N2O, sendo as emissões aumentadas com a elevação da CMRA de 40 para 60%.Perdas de N (N2 + N2O) do K15NO3variaram de 0,04 a 48,26%. No segundo experimento não foram observadas emissões nos tratamentos com 15ureia. Nos tratamentos com 15NH4 15NO3, somente N2O foi detectado.A vinhaça potencializou as emissões de N2O, mas os fatores de emissão ficaram abaixo de 0,4%. A não detecção do N2 levantou a hipótese que o enriquecimento isotópico dos fertilizantes foi insuficiente para marcar o N2 do interior das câmaras. Então, no último experimento, utilizou-se o 15NH4 15NO3enriquecido a 98 e a 10,43% para as determinações de N2 e N2O, respectivamente. Neste experimento a manutenção da palha intensificou as emissões de N2O proveniente do 15NH4 15NO3; a umidade, a temperatura, o Nmineral e o C-lábil do solo não apresentaram correlações significativas com emissões de N2O. Os fatores de emissão foram inferiores a 0,2%. No último experimento, também não foi detectado o N2, sugerindo que o N2O tenha sido o produto final da desnitrificação nos experimentos de campo. Os resultados mostraram que as adaptações realizadas no método do traçador 15N foram eficazes para a quantificação dos gases. Outras adaptações, entretanto, deverão surgir à medida que a adoção do método do traçador 15N se intensifique no Brasil / N2 and N2O emissions decrease the fertilization efficiency and can cause environmental damages. The 15N tracer method is used to measure N2 and N2O emissions, but there are no reports of its application in Brazil. The objective of the present study was to adapt the 15N tracer method to Brazilian conditions to quantify the N2 and N2O from fertilizers applied in sugarcane crop. Three experiments were conducted to adjusting the method: one in controlled conditions and the others in field. In controlled conditions, three soils with distinct textural class were evaluated. It was measured the moisture content (40, 60 and 80 % of water holding capacity - CMRA) and two levels of dextrose (0 and 500 mg C kg-1). K15NO3 (23.24 atom% 15N) was the N source used (100 mg kg-1). The field experiments were carried out on a RhodicDystrudox in Piracicaba region, Sao Paulo state. In the second experiment, two N sources (urea and NH4NO3, both with 31.9 atom% 15N), two N levels (55 and 110 kg ha-1) and two vinasse addition levels (0 and 100 m³ ha-1) were evaluated. In the third experiment, two N levels (70 and 140 kg ha-1) using 15NH4 15NO3 as N source, two vinasse levels (75 and 150 m³ ha-1) and the presence (11 Mg ha-1) or not of straw covering were evaluated. In each experiment, we try to improve our sampling protocol, gases preparing and analysis based on the limitations detected. In the first experiment, the N2O emissions occurred only in dextrose presence and were increased when the CMRA was raised to 60%. The N losses (N2+N2O) from K15NO3 varied from 0.04 to 48.26%. In the second experiment, it was not observed N2O emission with urea fertilization. In the treatments with NH4NO3 fertilization, it was only observed N2O emission. The vinasse application potentiated the N2O emissions, but the emissions factors were below 0.4 %. We believed that fertilizer isotopic enrichment was not sufficient to label the N2 inside chambers and because of this it was not possible measure N2 emission. So, in the last experiment, we used the 15NH4 15NO3 enriched with 98 and 10.43 atom% 15N to measure the N2 and N2O emission, respectively. In the same experiment, the straw maintenance on soil surface increased the N2O emissions from NH4NO3. The moisture, temperature, N-mineral and the C-labile were not significantly correlated with N2O emissions. The emissions factors were under of 0.2%. In the last experiment, likewise, it was not detected N2 emission, suggesting that the final product from denitrification was N2O in field experiments. Our results showed that adaptations realized in 15N tracer method were effective to quantify gases emissions. However, others adaptations can arise as result of intensification in adoption of 15N tracer method in Brazil
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Biosynthèse des unités isopréniques chez les végétaux / Biosynthesis of isoprene units in plantsGastaldo, Clément 16 April 2014 (has links)
Cette thèse de Doctorat est rattachée au projet européen Eulafuel, visant à concevoir un biocarburant à partir des triterpènes du latex de l’épurge Euphorbia lathyris. Notre mission consiste à étudier l’origine biosynthétique des unités isopréniques constituant ces molécules. Proviennent-elles de la voie du mévalonate (MVA) et/ou de la voie du méthylérythritol phosphate (MEP) ? En premier lieu, nous avons mis au point un protocole de culture de la plante en conditions axéniques et comparé les profils triterpéniques de plantes cultivées dans différentes conditions. Nous avons ensuite montré, grâce à des expériences d’incorporation de précurseurs marqués au 13C et au 2H, que les isoprénoïdes d’E. lathyris étaient produits via la voie du MVA. La seconde partie de ce travail porte sur l’étude de l’origine biosynthétique d’isoprénoïdes de végétaux par GC-iRMS, une intéressante alternative aux expériences de marquage. Nous avons comparé les signatures isotopiques δD et δ13C des lipides provenant de huit organismes phototrophes et formulé plusieurs hypothèses permettant d’expliquer les différences de fractionnement isotopique observées. / This PhD thesis is included in a European project, Eulafuel, aiming to use latex triterpenes of caper spurge (Euphorbia lathyris) as a biofuel source. Our investigation focuses on the biosynthetic origin of isoprene units. Are they produced via mevalonate (MVA) pathway and/or methylerythritol phosphate (MEP) pathway? First, we proposed a procedure to cultivate E. lathyris in axenic conditions, and we compared triterpenic profiles from plants grown in different conditions. Then, we showed, by incorporating 13C- and 2H-labeled precursors, that E. lathyris isoprenoids were produced via MVA pathway. The second part of this work is based on an isotopic analysis of plant isoprenoids by GC-iRMS, an interesting alternative to labeling experiments. We compared isotopic signatures (δD and δ13C) of lipids arising from eight phototrophic organisms and we proposed several hypothesis to explain the isotopic fractionation differences we observed.
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Dynamics of soil organic matter amino acids : a carbon isotope approach / Dynamique des acides aminés des matières organiques des sols : approche par les isotopes stables du carboneKheir Beik, Louay 10 May 2017 (has links)
Cette thèse aborde un point clé du couplage entre ces cycles: la dynamique des molécules azotées (AAs) des matières organiques du sol (MOS). Par des expériences d'incubation, nous avons estimé que les flux de biosynthèse des AAs par les micro-organismes du sol lors du processus de décomposition sont de l'ordre de 25% de la biomasse nouvellement formée. Le profil des AAs individuels biosynthétisés de novo est plus dépendant du type de sol que de la nature du substrat. Dans chaque sol, il est très similaire à celui des AAs des MOS. La biodégradation de matériaux végétaux marqués en 13C a révélé la transformation rapide des protéines végétales en matériaux microbiens. Ces résultats montrent que les AAs des MOS sont d'origine microbienne. Nous avons mesuré le renouvellement du C des AAs à long terme dans les horizons de surface de neuf sites présentant des végétations, climats et types de sol variés, en utilisant la technique de traçage par les abondances naturelles en 13C. L'âge moyen du carbone des AAs varie de 50 à 200 ans. Un modèle simple permet de discuter les hypothèses du recyclage des AAs des MOS par les micro-organismes. Les rapports isotopiques stables des AAs individuels ont été mesurés par chromatographie en phase gazeuse couplée à la spectrométrie de masse isotopique. À cette fin, nous avons développé une méthode d'étalonnage générique pour la détermination du rapport isotopique des composés spécifiques, par analyse de cultures microbiennes uniformément marquées. Au-delà des résultats présentés, l'étude apporte un large ensemble de données des AAs et examine les variations de l'abondance naturelle en 13C entre les AAs individuels. / We analyzed the coupled dynamics of C and N in Soil Organic Matter (SOM) through the dynamics of N-containing soil organic compounds (amino acids (AAs)) by tracing their carbon atoms. Stable isotope ratios of individual amino acids were measured by gas chromatography coupled with isotope ratio mass spectrometry. For this purpose, we developed a generic calibration method for compound-specific stable isotope ratio analysis, based on the analysis of uniformly labelled microbial cultures. We quantified the biosynthesis of AAs associated with the biodegradation process in four contrasted topsoils through short-term incubation experiments of 13C-labelled substrates. Amino acids-C accounts for ca. 25% of the newly-formed microbial biomass-C. The composition of the de novo biosynthesized individual amino acids was dependent on the soil type, and in each soil was similar to that of SOM amino acids. Biodegradation of 13C-labelled plant materials revealed the rapid conversion of plant proteins into microbial materials. These results together demonstrate that SOM amino acids are of microbial origin. We measured the dynamics of amino acids-C on the long term (decades to centuries) in nine sites using the natural 13C-labelling technique. On average, the age of AAs was equal or slightly inferior to that of bulk soil organic carbon, with mean ages ranging from 50 to 200 years. We built a conceptual model of AAs dynamics to discuss various hypotheses of AAs stabilization. Beyond these perspectives on C and N coupling in soil processes, the overall study brings a broad dataset of amino acids, as well as discuses variations of 13C natural abundance (δ13C) in-between individual amino acids.
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Caracterização dos vinhos Merlot e Cabernet Sauvignon da serra gaúcha através de determinação das razões isotópicas 13C/12C e 18O/16OAdami, Laurien 19 December 2006 (has links)
Neste trabalho foram estudados vinhos provenientes de microvinificações das variedades Merlot e Cabernet Sauvignon das sub-regiões de Pinto Bandeira, Vale dos Vinhedos, Nova Pádua e Monte Belo do Sul, nas safras de 2005 e 2006. Foram determinadas as razões isotópicas 13C/12C do etanol e 18O/16O da água e do etanol, buscando possível diferenciação entre as variedades e safras de produção, e provável relação entre o local de origem e suas características geográficas (altitude e latitude) e climatológicas (temperatura, precipitação pluviométrica e umidade). Utilizou-se um espectrômetro de massas de razão isotópica (IRMS) acoplado a um analisador elementar, para análise de 13C/12C do etanol e 18O/16O da água e a um cromatógrafo gasoso, para análise de 18O/16O do etanol. Em relação aos valores de δ13C, observou-se que a diferenciação entre as sub-regiões amostrais são menos seletivas e não seguem mesma ordem estatística encontrada para as análises δ18O, porém a análise de δ13C do etanol pode servir para diferenciar sub-regiões que não são diferenciadas estatisticamente pelas análises de δ18O. O comportamento dos valores de δ18O da água e do etanol obedecem mesma ordem estatística de diferenciação. Independente da variedade de uva utilizada neste trabalho, foi possível diferenciar as sub-regiões através da análise isotópica de δ18O, nas duas safras de produção, com exceção do Vale dos Vinhedos e Monte Belo do Sul, safra 2005, que não apresentaram diferenças estatísticas. As latitudes das diferentes sub-regiões apresentaram diferença estatística e demonstraram influência principalmente nos valores de δ18O da água. As análises de δ18O da água e do etanol do vinho mostraram-se mais seletivas e eficientes na discriminação das sub-regiões de cultivo do que as análises de δ13C do etanol. Foi observada uma forte correlação entre os valores de δ18O da água e do etanol. A altitude e a latitude influenciam principalmente os valores de δ18O da água e do etanol. As influências climáticas são mais marcantes na distinção entre safras de produção do que sub-regiões de cultivo. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-14T18:11:59Z
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Dissertacao Laurien Adami.pdf: 946622 bytes, checksum: 1405d2dd9ccbcd048e59ac45e36fd0f7 (MD5) / Made available in DSpace on 2014-05-14T18:11:59Z (GMT). No. of bitstreams: 1
Dissertacao Laurien Adami.pdf: 946622 bytes, checksum: 1405d2dd9ccbcd048e59ac45e36fd0f7 (MD5) / In this work, wines provided by micro-winemakings of the variety Merlot and Cabernet Sauvignon of the sub-regions of Pinto Bandeira, Vale dos Vinhedos, Nova Pádua and Monte Belo do Sul in the 2005 and 2006 harvest have been studied. It has been established the isotopic ratios 13C/12C of the ethanol and 18O/16O of the water and ethanol, seeking for a possible differentiation among the varieties and production harvests, and a possible relation between the place of origin and its geographic features (altitude and latitude) and climatological conditions (temperature, precipitation and humidity). It has been used a isotope ratio mass spectrometer (IRMS) coupled to an elementar analyzer for the analysis of the 13C/12C of the ethanol and 18O/16O of the water and to a gas chromatograph for the analysis of 18O/16O of the ethanol. In relation to the values of δ13C, it is observed that the differentiation among the sampling sub-regions are less selective and do not follow the same statistical order found for the analysis of δ18O, however, the analysis of δ13C of the ethanol may be used to differentiate sub-regions that are not differentiated statistically by the analysis of δ18O. The value behaviors of δ18O of the water and the ethanol follow the same statistical order of differentiation. Regardless of the grape variety used in this work, it has been possible to differentiate the sub-regions through the isotopic analysis of the δ18O, in both production harvests, except for the Vale dos Vinhedos and Monte Belo do Sul, 2005 harvest, which did not present statistical differences. The latitudes of the different sub-regions presented statistical differences and demonstrated an influence mainly in the values of δ18O of the water. The analysis of δ18O of the water and the ethanol of the wine conveyed to be more selective and efficient in the discrimination of the cultivation sub-regions than the analysis of δ13C of the ethanol. It has been observed a strong correlation between the values of δ18O of the water and the ethanol. The altitude and latitude influence mainly the values of δ18O of the water and the ethanol. The climate influences are more noteworthy in distinguishing the production harvests than the cultivation sub-regions.
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Caracterização dos vinhos Merlot e Cabernet Sauvignon da serra gaúcha através de determinação das razões isotópicas 13C/12C e 18O/16OAdami, Laurien 19 December 2006 (has links)
Neste trabalho foram estudados vinhos provenientes de microvinificações das variedades Merlot e Cabernet Sauvignon das sub-regiões de Pinto Bandeira, Vale dos Vinhedos, Nova Pádua e Monte Belo do Sul, nas safras de 2005 e 2006. Foram determinadas as razões isotópicas 13C/12C do etanol e 18O/16O da água e do etanol, buscando possível diferenciação entre as variedades e safras de produção, e provável relação entre o local de origem e suas características geográficas (altitude e latitude) e climatológicas (temperatura, precipitação pluviométrica e umidade). Utilizou-se um espectrômetro de massas de razão isotópica (IRMS) acoplado a um analisador elementar, para análise de 13C/12C do etanol e 18O/16O da água e a um cromatógrafo gasoso, para análise de 18O/16O do etanol. Em relação aos valores de δ13C, observou-se que a diferenciação entre as sub-regiões amostrais são menos seletivas e não seguem mesma ordem estatística encontrada para as análises δ18O, porém a análise de δ13C do etanol pode servir para diferenciar sub-regiões que não são diferenciadas estatisticamente pelas análises de δ18O. O comportamento dos valores de δ18O da água e do etanol obedecem mesma ordem estatística de diferenciação. Independente da variedade de uva utilizada neste trabalho, foi possível diferenciar as sub-regiões através da análise isotópica de δ18O, nas duas safras de produção, com exceção do Vale dos Vinhedos e Monte Belo do Sul, safra 2005, que não apresentaram diferenças estatísticas. As latitudes das diferentes sub-regiões apresentaram diferença estatística e demonstraram influência principalmente nos valores de δ18O da água. As análises de δ18O da água e do etanol do vinho mostraram-se mais seletivas e eficientes na discriminação das sub-regiões de cultivo do que as análises de δ13C do etanol. Foi observada uma forte correlação entre os valores de δ18O da água e do etanol. A altitude e a latitude influenciam principalmente os valores de δ18O da água e do etanol. As influências climáticas são mais marcantes na distinção entre safras de produção do que sub-regiões de cultivo. / In this work, wines provided by micro-winemakings of the variety Merlot and Cabernet Sauvignon of the sub-regions of Pinto Bandeira, Vale dos Vinhedos, Nova Pádua and Monte Belo do Sul in the 2005 and 2006 harvest have been studied. It has been established the isotopic ratios 13C/12C of the ethanol and 18O/16O of the water and ethanol, seeking for a possible differentiation among the varieties and production harvests, and a possible relation between the place of origin and its geographic features (altitude and latitude) and climatological conditions (temperature, precipitation and humidity). It has been used a isotope ratio mass spectrometer (IRMS) coupled to an elementar analyzer for the analysis of the 13C/12C of the ethanol and 18O/16O of the water and to a gas chromatograph for the analysis of 18O/16O of the ethanol. In relation to the values of δ13C, it is observed that the differentiation among the sampling sub-regions are less selective and do not follow the same statistical order found for the analysis of δ18O, however, the analysis of δ13C of the ethanol may be used to differentiate sub-regions that are not differentiated statistically by the analysis of δ18O. The value behaviors of δ18O of the water and the ethanol follow the same statistical order of differentiation. Regardless of the grape variety used in this work, it has been possible to differentiate the sub-regions through the isotopic analysis of the δ18O, in both production harvests, except for the Vale dos Vinhedos and Monte Belo do Sul, 2005 harvest, which did not present statistical differences. The latitudes of the different sub-regions presented statistical differences and demonstrated an influence mainly in the values of δ18O of the water. The analysis of δ18O of the water and the ethanol of the wine conveyed to be more selective and efficient in the discrimination of the cultivation sub-regions than the analysis of δ13C of the ethanol. It has been observed a strong correlation between the values of δ18O of the water and the ethanol. The altitude and latitude influence mainly the values of δ18O of the water and the ethanol. The climate influences are more noteworthy in distinguishing the production harvests than the cultivation sub-regions.
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Caractérisation moléculaire et isotopique de goudrons et résines archéologiques dérivés de conifères en contexte maritime / Molecular and isotopic characterization of archaeological softwood tars and resins in maritime contextBailly, Lucile 08 April 2015 (has links)
De tous temps, les Pinacées ont été utilisés pour leur résine ou le goudron que l’on peut en tirer, principalement dans le domaine maritime (calfatage, protection des cordages) et pour le poissage d’amphores. Ces travaux ont été consacrés au développement de nouveaux outils moléculaires et isotopiques pour la caractérisation de tels matériaux trouvés en contexte archéologique (distinction goudron / résine, origine taxonomique et géographique, modes de fabrication). Sur la base des outils développés, il apparait que l’utilisation de goudron prévaut dans ce contexte sur celle de résine et que les Pinus, dont les espèces peuvent être partiellement discriminées, sont les principaux Pinacées utilisés. Il a aussi pu être montré que les matériaux de calfatage et d’enduits de cordages sont globalement issus d’une cuisson moins poussée que ceux utilisés dans le poissage de récipients. Une distinction des échantillons archéologiques sur la base de leur composition isotopique en D a été proposée. / Resins and tars of Pinaceae have been used in the past mainly in the maritime field (caulking, protection of the ropes) and for the waterproofing of jars and amphorae. This study was devoted to the development of new molecular and isotopic tools for the characterization of such materials found in archaeological context (discrimination between tar / resin, taxonomic and geographical origin, manufacturing methods). Based on the detailed molecular and isotopic investigation of diterpenic compounds, in particular, it appears that the use of tar prevails in this context over that of resin and that trees from the genus Pinus, which can be partially discriminated in terms of species, have been preferentially used. It could be shown that the caulking material and the tar protecting ropes result overall from a less intense heating process than the material used to waterproof containers. A distinction of the archaeological samples on the basis of their isotopic composition in D was proposed.
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Sources, Transport, Measurement and Impact of Nano and Microplastics in Urban WatershedsBirch, Quinn T. January 2019 (has links)
No description available.
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Dynamique des HAP et des composés organiques issus de leur transformation dans les compartiments du sol et de la rhizosphère / Fate and behaviour of polycuclic aromatic hydrocarbons (PAHs) and their transformation products in soil fractions and plant rhizosphereCennerazzo, Johanne 10 April 2017 (has links)
Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants persistants retrouvés majoritairement dans l’environnement, qui sont reconnus comme hautement toxiques pour les organismes vivants. Les nombreux travaux réalisés sur les mécanismes contrôlant l’évolution des HAP dans le sol et dans la rhizosphère ont mis en exergue le rôle majeur de la biodégradation par les microorganismes et de la sorption aux constituants du sol. Néanmoins, un manque d’informations persiste concernant le devenir de ces HAP dans le sol, et plus particulièrement leur localisation dans les compartiments du sol ainsi que la nature et le comportement des composés issus de leur dégradation. La thèse avait donc comme principaux objectifs : (a) la localisation des HAP et des produits dérivés dans les compartiments du sol (matières organiques, phases minérales, microorganismes et plante), et (b) la quantification et l’identification des composés organiques formant les résidus liés du sol. Pour cela, nous avons couplé deux approches:(i) le suivi d’un HAP modèle marqué, le 13C-phénanthrène (13C-PHE), dans un sol artificiellement contaminé planté et non planté pour notamment déterminer par IRMS et NanoSIMS la distribution du C issu du PHE dans les compartiments et pour identifier les composés dérivés du 13C-PHE par 13C-RMN et TD/pyGCMS. (ii) le suivi d’une contamination ancienne et récente en HAP dans un sol historiquement contaminé pour étudier l’influence des matières organiques et des phases minérales (séparées par un fractionnement densimétrique) dans la rétention des HAP. Plus de 40% du C issu du 13C-PHE est retenu dans le sol après 14 jours de croissance du ray-grass. L’enrichissement en 13C observé dans la plante est du même ordre que celui du sol (E13C ≈ 0.04 % at.) démontrant une incorporation homogène du 13C-PHE entre la plante et le sol. Cet enrichissement global dans la plante est confirmé par les images NanoSIMS réalisées sur les racines. Des hotspots en 13C ont également été observés dans la rhizosphère, et à partir de leur taille, leur forme et leur composition élémentaire en C, N et S ils ont été identifiés comme étant des bactéries, ce qui met en avant leur rôle dans la dynamique des HAP du sol. Dans le sol industriel, la majorité des HAP est retrouvée dans les MO non complexées aux minéraux. En revanche, les HAP fraîchement ajoutés se sont significativement liés aux associations organo-minérales composées de quartz, de feldspaths et de phyllosilicates / Polycyclic aromatic hydrocarbons (PAHs) are major persistent pollutants in the environment that are recognized as highly toxic to living organisms. Numerous studies were carried out on the fate of PAHs in soil and in plant rhizosphere and highlighted the major contribution of biodegradation processes and of the sorption to soil constituents. However, a lack of knowledge remains about the fate of PAHs in the soil and especially their location in soil compartments as well as the nature and the behavior of degradation products. The main objectives of the thesis were: (a) to localize PAHs and their derived products within soil compartments (organic matter, minerals, microorganisms and plant), and (b) to quantify and identify the organic compounds forming bound residues. For this purpose, we used two approaches: (i) the monitoring of a labeled PAH, the 13C-phenanthrene (13C-PHE), in a spiked soil planted or not to determine by IRMS and NanoSIMS the 13C-distribution into compartments and to identify derived compounds of 13C-PHE by 13C-RMN et TD/pyGCMS. (ii) the distribution and localization of aged and freshly spiked PAH contamination in a brownfield soil to study the impact of organic matter and minerals (using soil densimetric fractionation) in the PAH retention. More than 40% of C from 13C-PHE remained in the soil after 14 days of ryegrass growth. The 13C-enrichment in plant tissue was similarly to the soil enrichment (E13C ≈ 0.04 at.%) indicating uniform uptake of 13C-PHE between the soil and plant. NanoSIMS images acquired for roots confirmed this global enrichment in the plant. 13C-Hospots were also observed in the rhizosphere, and on the basis on their size, their shape and their elemental composition in C, N and S, they were identified as bacteria, which emphasize their contribution to the fate of PAHs in soil. In the industrial soil, most of the PAHs were found attached to the free OM. However, the freshly spiked PAHs in the soil were significantly associated with organo-mineral associations containing quartz, feldspars and phyllosilicates
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Développement de méthodologies analytiques et statistiques pour le contrôle de la naturalité de matières premières pour la cosmétique et la parfumerie / Development of innovative analytical and statistical methodology for the naturality control of raw materials perfumery and cosmetic industriesMazollier, Aude 11 January 2013 (has links)
Les huiles essentielles extraites de plantes aromatiques, médicinales et à parfum, sont utilisées depuis des millénaires pour leurs propriétés médicinales ou olfactives. Pour des raisons de rentabilité, les distributeurs sont contraints à réduire leur coût au maximum et à commercialiser des huiles essentielles au plus bas prix. Certains ont recours à la fraude et proposent, des essences de qualité inférieure sous la dénomination produits naturels de haute qualité. Il existe des normes (AFNOR, pharmacopées) qui doivent être respectées. Mais leur seule application est souvent limitée. Cette étude a donc permis une nette amélioration du contrôle de la naturalité des huiles essentielles de citrus, et lavande. La connaissance des compositions moléculaires des volatiles et des polymethoxyflavones (citron), l'étude énantiomérique de molécules cibles telles que l'alpha-pinène, le sabinène (citrus), le linalol et l’acétate de linalyle (bergamote et lavande), les analyses isotopiques du carbone 13, deutérium, des linalol, acétate de linalyle (bergamote et lavande), citral, acétate de géranyle (citron) ainsi que les analyses isotopiques du deutérium et azote 15 du N-méthyle anthranilate de méthyle (mandarine) sont les analyses permettant la mise en évidence de nombreux types de fraudes. Pour une méthodologie efficace, les analyses en composante principale et discriminante ont été indispensables. Elles ont permis l’identification d’échantillons fraudés via l’étude des volatiles. Les analyses chirales et isotopiques permettent l'identification d'échantillon plus “ finement ” adultérés ou de mieux comprendre les processus de fraude / Essential oils extract from aromatics, medicinal and perfume plants, are used since ancient times for their medicinal or olfactory properties. They are quite expensive, and owing to the actual growing demand for getting high quality materials at lowest prices, fraudulent essential oils are frequently found on the market. In order to fight this problem, norms exist (AFNOR, pharmacopeas) which have to be respected. However those techniques are often limited. This work allowed great improves in the quality control of citrus and lavender essential oils. The knowledge of the chemical composition of volatiles and polymethoxy-flavones (lemon), of the chirale ratios of alpha-pinene, le sabinene (citrus), linalool et linalyl acetate (bergamot et lavender), isotope ratio analyses of carbon 13, deuterium, of linalool, linalyl acetate (bergamot et lavender), citral, geranyl acetate (lemon) as wall as isotope ratio analyses of deuterium of nitrogen 15 du Nmethyl anthranilate de methyl (mandarin) permitted the detection of various type of frauds. In order to have an efficient methodology, principal component and discriminant analyses have been proved indispensables. It allowed the identification of fraudulent samples via volatiles molecules study. Chirale analysis and isotope ratio highlight frauds on more “discrete” adulterated samples or a better understanding of adulteration’s process
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