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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Contribution à l’étude de la fission nucléaire : de LOHENGRIN à FIPPS / Nuclear fission studies : from LOHENGRIN to FIPPS

Chebboubi, Abdelaziz 28 October 2015 (has links)
La fission nucléaire consiste en la brisure d'un noyau lourd, généralement un actinide, en deux noyaux plus légers (ou trois dans quelques rares cas). Ce phénomène a été découvert par Hahn et Strassman en 1938. Très rapidement Meitner et Frisch proposèrent une explication théorique pour ce processus à l'aide du modèle de la goutte liquide. Depuis les modèles n'ont cessé d'évoluer et de se complexifier à travers l'ajout de nouveaux mécanismes et l'observation de nouveaux phénomènes. L'amélioration des modèles est un enjeu important à la fois pour la compréhension fondamentale du processus de fission mais aussi pour les applications. En effet, le dimensionnement des réacteurs futurs s'appuie de plus en plus sur des simulations numériques. Il devient dès lors primordial de réduire les incertitudes associées aux données utilisées. Cela passe alors par la validation des hypothèses sous-jacentes des modèles de fission nucléaire.Dans le cadre de cette thèse, on s'intéresse à deux aspects de la fission nucléaire qui permettront de tester la robustesse des théories. L'un des aspects concerne l'étude des fragments de fission issus de la région de la symétrie à travers la mesure des rendements et des distributions en énergie cinétique. L'autre aspect étudié est le moment angulaire des fragments de fission.Afin d'accéder au moment angulaire des fragments de fission, l'une des possibilités est d'analyser les propriétés des particules promptes, qui est l'une des ambitions du projet FIPPS (FIssion Product Prompt gamma-ray Spectrometer). Une partie de ce travail a été de caractériser les propriétés des spectromètres magnétiques gazeux à travers des mesures expérimentales et le développement d'une simulation Monte Carlo.La seconde partie de ce travail a consisté en la mesure de rapports isomériques et en l'extraction de la distribution du moment angulaire des fragments de fission à l'aide d'un code de désexcitaiton nucléaire. La mesure d'un noyau doublement magique ($^{132}$Sn) permet de mettre en lumière les limites actuelles des modèles de fission.Enfin la dernière partie de ce travail porte sur la mesure des rendements et des distributions en énergie cinétique des fragments de fission. Certains modèles prédisent l'existence de modes dans la fission nucléaire. La région des masses symétriques est dès lors un lieu de choix pour vérifier la validité de ces affirmations.Il est à noter qu'en parallèle de ces études, un accent fort a été mis sur le développement de méthodes d'analyse s'appuyant sur des outils statistiques afin notamment d'améliorer l'évaluation des incertitudes expérimentales. / Nuclear fission consists in splitting a nucleus, in general an actinide, into smaller nuclei. Despite nuclear fission was discovered in 1939 by Hahn and Strassman, fission models cannot predict the fission observables with an acceptable accuracy for nuclear fuel cycle studies for instance. Improvement of fission models is an important issue for the knowledge of the process itself and for the applications. To reduce uncertainties of the nuclear data used in a nuclear reactor simulation, a validation of the models hypothesis is mandatory.In this work, two features of the nuclear fission were investigated in order to test the resistance of the theories. One aspect is the study of the symmetric fission fragments through the measurement of their yield and kinetic energy distribution. The other aspect is the study of the fission fragment angular momentum.Two techniques are available to assess the angular momentum of a fission fragment. The first one is to look at the properties of the prompt $gamma$. The new spectrometer FIPPS (FIssion Product Prompt gamma-ray Spectrometer), is currently under development at the ILL and will combine a fission filter with a large array of $gamma$ and neutron detectors in order to respond to these issues. The first part of this work is dedicated to the study of the properties of a Gas Filled Magnet (GFM) which is the type of fission filter considered for the FIPPS project.The second part of this work deals with the measurement of isomeric yields and evaluations of the angular momentum distribution of fission fragments. The study of the spherical nucleus $^{132}$Sn shed the light on the current limits of fission models.Finally, the last part of this work is about the measurement of the yields and kinetic energy distributions of symmetric fission fragments. Since models predict the existence of fission modes, the symmetry region is a suitable choice to investigate this kind of prediction.In parallel with all these studies, an emphasis on the development of new methods derived from statistical tools is achieved in order to better control the uncertainties and estimate the biases.
62

Ácido Salicílico, abcísico e jasmônico em videiras submetidas ou não à aplicação da tecnologia TPC (Thermal Pest Control) / Salicylic acid, abscisic acid and jasmonic acid in vines submitted or not to the application of TPC technology (Thermal Pest Control)

Domingues, Bruno Alves 16 May 2013 (has links)
A aplicação de ar quente em videiras foi primeiramente realizada na fazenda do Sr. Florenzo Lazo, localizada no Chile, onde havia a necessidade de combater os efeitos negativos das freqüentes geadas que resultava em severos danos à lavoura. Por este motivo o Sr. Florenzo inventou uma máquina que aplicava ar quente com baixa umidade e tinha por objetivo dispersar o ar frio proveniente das geadas. Após certo tempo, foi observado pelo produtor que no local onde a máquina havia operado com maior frequência as plantas apresentavam-se com uma coloração mais escura e com sinais de maior vitalidade. Seguindo estas observações, relacionamos estes efeitos a um possível aumento nos fito-hormônios relacionados ao estresse vegetal e à SAR (Systemic Resistence Adquired), como o ácido salicílico (AS), ácido jasmônico (AJ) e ácido abscísico (ABA), além de fazer uma correlação com alguns resultados de pós-colheita importantes para a comercialização, como: Sólidos solúveis, firmeza e coloração. Para isso foi montado um experimento que foi conduzido em duas parcelas, sendo uma com tratamento TPC e outra apenas com o tratamento convencional com distância padronizada em 3,2 metros entre linhas por 2,0 metros entre planta. As amostras eram coletadas diariamente e devidamente acondicionadas. Ao final da safra, as amostras foram transportadas para o laboratório de estresse e neurofisiologia da universidade de São Paulo (LEPSE), onde foram novamente armazenadas em um Ultra-freezer - 86ºC. As analises fisiológicas de pós-colheita foram realizadas no departamento de pós-colheita da universidade de São Paulo onde foram analisados os teores de sólidos solúveis, coloração e firmeza das bagas de uva. As amostras de folhas foram maceradas e uniformizadas no LEPSE e enviadas para o laboratório de ecotoxicologia do Centro de Energia Nuclear na Agricultura (CENA) onde foram mensurados os teores dos fito-hormônios pelo método de espectrometria de massa. Para ambas as analises foram feitos testes estatísticos utilizando o programa SAS®. Não houve alteração de SS e firmeza entre os dois tratamentos para as características fisiológicas de póscolheita. Entretanto foi notado uma redução na coloração avermelhada para os cachos tratados com TPC seguindo o sistema de colorimetria proposto pelo CIE. Não houve alterações significantes para as variáveis ABA, AJ e AS para o efeito tratamento e para a analise de correlação. Entretanto notou-se significância entre o efeito dias para as variáveis ABA e AJ. Não foi notada significância para o efeito dias para a variável AS. Por se tratar de um estresse rápido, a TPC parece não causar estresse imediato nas plantas, entretanto notou-se indução de estresse ao longo do tempo, possivelmente devido à resposta lenta de ABA que aparentemente está envolvida com RNA e à síntese de proteínas S e R- ABA que são igualmente efetivas. Já para o AJ sugere-se que houve a produção de H2O2 por derivados de oligogalacturonideos, liberados por ação da enzima poligalacturonase, e um segundo mensageiro que ativam genes defensivos (genes tardios). O aumento na biossíntese do ABA e do AJ parece ter suprimido genes envolvidos na biossíntese do AS. / The application of hot air in grapevines was first held on the farm of Mr. Florenzo Lazo, located in Chile, to combat the negative effects of frequent frosts that resulted in severe damage to the crop. For this reason Mr. Florenzo invented a machine that applied hot air with low humidity and aimed to disperse the cold air from the frost. After a while, it was observed by the producer that where the machine had operated more frequently plants showed up with a darker and more signs of vitality. Following these observations, these effects relate to a possible increase in phytohormones related to plant stress and SAR (Systemic Resistance Adquired), such as salicylic acid (AS), jasmonic acid (AJ) and abscisic acid (ABA), besides making a correlation with results of some important postharvest for marketing, such as soluble solids, firmness and color. For this experiment was created that was conducted in two installments, the first one was treated with TPC and second one was applied only conventional treatment with standardized distance of 3.2 meters between lines by 2.0 meters between plant . The samples were collected daily and properly packed. At the end of the season, samples were transported to the laboratory stress and neurophysiology from the University of São Paulo (LEPSE), where they were again stored in an Ultra-freezer - 86 degrees. The physiological analyses of post-harvest were performed at the Department of Postharvest in University of Sao Paulo where we analyzed the levels of soluble solids, firmness and color in grape berries. The leaf samples were uniform macerated at LEPSE and sent to the laboratory of ecotoxicology in the Center for Nuclear Energy in Agriculture (CENA) where we measured the levels of the phytohormones by the method of mass spectrometry. For both analyzes were performed statistical tests using SAS ® program. There wasn`t change between the two treatments on physiological post-harvest characteristics. There was no change of SS and firmly between the two treatments for the physiological of post-harvest characteristics. However it was noted a reduction in red color for bunches treated with TPC following the colorimetry system by CIE. There were no significant changes to the variables ABA, AJ and AS for the treatment effect and to analyze the correlation. However significance was noted between the effect variables ABA days and AJ. No significant effect was noted for days variable for AS. Since it is a stress fast TPC does not seem to cause immediate stress in plants but it was noticed induction of stress over time, possibly due to slow response to ABA which apparently is involved in the synthesis of RNA and proteins S and R-ABA that are equally effective. As for AJ suggests that there was the production of H2O2 by derivatives of oligogalacturonides, released by action of the enzyme polygalacturonase, and a second messenger that activates defensive genes (late genes). The increase in ABA biosynthesis and AJ appears to have deleted genes involved in the biosynthesis of AS.
63

Screening of volatile compounds in washing water and cloths from the sponge cloth process

Bergner, Sandra, Nilsson, Sandra January 2010 (has links)
<p>Freudenberg Household Products AB in Norrköping are manufacturer of sponge cloths with the well-known brand names of Wettex<sup>®</sup> and Vileda<sup>®</sup>. The production is based on the viscose fiber process and involves a high chemical demand. Recent customer complaints involve a diffuse smell from the cloths that is like a “garage odor” and occurs after a few uses. The company’s theory is that the smell derives from a chemical used in the process called Exxal 9.</p><p>The aim was to screen the washing water from two sections and the cloth before and after wash for the presence of Exxal 9 and other prominent components. The washing water samples consisted of a salt solution from one section and a water condensate from another section. A method to qualitatively and quantitatively examine the production samples was developed. To evaluate the variation over a short period of time, twelve samples were taken during four weeks. The focus for the analysis lay on production line Wx4, but comparisons with two other production lines, Wx7 and SL1, were also made. The method of choice was gas chromatography in combination with two different detectors; mass spectrometer for identification and flame ionization detector for quantification.</p><p>Exxal 9 could be identified in both of the washing water sections but in very various concentrations. At the production line Wx4, the mean concentration in the mother lye was 61.96 µl/l whereas the mean concentration in the condensate was 0.24 µl/l. The comparison between the different production lines showed significant variations, where Wx4 had the highest concentration. In the cloths, Exxal 9 could only be found before it had been washed. The concentration in the cloths was not high enough for quantification. In both the washing waters and cloths, additional unknown peaks were found. Attempts to identify all the unknowns were made but only two compounds were included in the commercial library; 2-ethyl-1-hexanol and 2-(2-butoxyethoxy)-ethanol.</p>
64

The Characterization of Fine Particulate Matter in Toronto Using Single Particle Mass Spectrometry

Rehbein, Peter J. G. 13 January 2011 (has links)
An Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) was used to obtain mass spectra of individual aerosol particles in the 0.5 – 2 µm size range in downtown Toronto, Canada for one to two month periods during each season of 2007. A modified version of the Adaptive Resonance Theory (ART-2a) clustering algorithm, which clusters particles based on the similarity of their mass spectra, was shown to be more accurate than the existing algorithm and was used to cluster the ambient data. A total of 21 unique particle types were identified and were characterized based on their chemical composition, their size, and their temporal trends and seasonal variations. Potential sources are also discussed. Particles containing trimethylamine (TMA) were also observed and a more detailed investigation of ambient trends in conjunction with a laboratory experiment was performed in order to elucidate conditions for which TMA will be observed in the particle phase in Southern Ontario.
65

The Characterization of Fine Particulate Matter in Toronto Using Single Particle Mass Spectrometry

Rehbein, Peter J. G. 13 January 2011 (has links)
An Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) was used to obtain mass spectra of individual aerosol particles in the 0.5 – 2 µm size range in downtown Toronto, Canada for one to two month periods during each season of 2007. A modified version of the Adaptive Resonance Theory (ART-2a) clustering algorithm, which clusters particles based on the similarity of their mass spectra, was shown to be more accurate than the existing algorithm and was used to cluster the ambient data. A total of 21 unique particle types were identified and were characterized based on their chemical composition, their size, and their temporal trends and seasonal variations. Potential sources are also discussed. Particles containing trimethylamine (TMA) were also observed and a more detailed investigation of ambient trends in conjunction with a laboratory experiment was performed in order to elucidate conditions for which TMA will be observed in the particle phase in Southern Ontario.
66

Resonant Excitation Of Ions In Paul Trap Mass Spectrometer

Sarurkar, Vikram A 06 1900 (has links)
A Paul trap mass spectrometer has a three-electrode geometry mass analyzer consisting of two identical end cap electrodes and a ring electrode. Traditionally, the two end cap electrodes are electrically grounded and an RF potential is applied to the central ring electrode to generate the "trapping field". Ions of the analyte sample are formed in situ by electron bombardment and mass analysis of the fragment ions is performed by mass selectively destabilizing the ions from the trap. The inhornogeneities present in the trapping field (introduced either by misalignment of the trap geometry or by applying a dipolar auxiliary excitation across the end cap electrodes) give rise to various interesting phenomena including, resonance ejection of the trapped ions This thesis is concerned with taking a look into the experimental aspects associated with resonance ejection of ions caused by the dipolar excitation Additionally, u also reports the work undertaken to develop necessary instrumentation for resonant excitation experiments and my contribution to operational>zc the Paul trap mass spectrometer fabricated in the laboratory. The thesis is divided into 5 chapters. Chapter 1 is an introductory chapter. After discussing the conditions for stability of the trapped ions, it goes on to present a brief survey of a variety of applications in literature, which have used resonant excitation. Towards the end, the motivation of the present effort and the scope of work in the thesis have been spelt out. This includes (a) redesign of the ion detector electronics, (b) design of an auxiliary excitation generator, and (c) studies on resonance ejection. Chapter 2 outlines the design considerations, circuit description and fabrication details for the ion detector electronics. The circuits presented in this chapter include (a) electrometer amplifier and (b) -3 kV DC supply for the electron multiplier detector. The electrometer amplifier amplifies the ion current signal from the electron multiplier detector and it needs to have a high input impedance and a high slew rate. The electron multiplier detector requires -3 kV DC power supply for operation. The -3 kV DC power supply is required to have a regulated output voltage with low ripple in the output. Chapter 3 presents the design considerations, circuit description and fabrication details for the auxiliary excitation generator. The auxiliary excitation generator is a three channel DDS (Direct Digital Synthesis) oscillator with independent control of frequency amplitude, and phase of the output signal. Chapter 3 also discusses the micro controller based control sub-system that allows the user to set above mentioned output parameters. The control sub-system provides a user-friendly keyboard interface and 2-line alphanumeric LCD display per channel. It also provides various bus interfaces (such as I2C and SPI) to interface with DDS oscillator ICs, amplitude control DAC, and LCD displays. The chapter then goes on to describe the implementation details of the software written for the control sub-system. The hardware design is simplified by using a micro controller as heart of the control sub-system and employing the software to handle the complex functions. As an example, the design of the keyboard interface is simplified by directly connecting a matrix keyboard to the input/output port of the micro controller. The software is used to scan the keyboard, detect key press and find out the key pressed. Nonetheless, in order to meet specific performance required for the present work, the software needs to have a sense of time, be portable and scalable. Details of the "layered" architecture adopted by as to meet these specific requirements, the lower level "driver" functions implemented for various interfaces of the control sub-system, and the higher level or the "application" software, are described. The application software uses the driver functions to accomplish various tasks required to be executed by the control sub-system. Finally, the chapter presents the design consideration and fabrication details of the coupling transformer used to couple the output of the auxiliary excitation generator to the Paul trap Chapter 4 describes the resonant excitation experiments performed as part of the present work. First of all the chapter presents the improvement in the performance of the Paul trap mass spectrometer as a result of redesigned ion detector electronics It is seen that the resolution is improved significantly due to the improved response time of the electrometer amplifier. The chapter then describes the effect of the resonant excitation on the ions and also that the frequency of the applied auxiliary excitation should be between 500 kHz to 125 kHz. Next, a number of mass spectra for different frequencies of the applied auxiliary excitation are presented. These mass spectra indicate that the resonant ejection sets in for lower masses even at lower amplitude of the auxiliary excitation where as higher amplitude is required for the resonant ejection of the higher masses. It is seen that the resonant excitation of ions improves resolution of the mass spectrum. Moreover, the auxiliary excitation results in ejection of the ions at lower amplitude of the RF voltage and thus allows extending the mass range of the mass spectrometer. We present the mass spectrum of CCI4 which is not possible to normally record in our instrument. We also present results intended to understand the relation between frequency and amplitude of the auxiliary excitation on the mass spectra of benzene. Finally, results of an interesting experiment are presented which indicates the presence of the non-linear resonance points in the Paul trap. Chapter 5 presents the concluding remarks. References cited in the thesis are attached in their alphabetical order at the end of the thesis.
67

Continuous real-time measurement of the chemical composition of atmospheric particles in Greece using aerosol mass spectrometry

Φλώρου, Καλλιόπη 04 November 2014 (has links)
Atmospheric aerosol is an important component of our atmosphere influencing human health, regional and global atmospheric chemistry and climate. The organic component of submicron aerosol contributes around 50% of its mass and is a complex mixture of tens of thousands of compounds. Real-time aerosol mass spectrometry was the major measurement tool used in this work. The Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) can quantitatively measure the chemical composition and size distribution of non-refractory submicron aerosol (NR-PM1). The mass spectra provided by the instrument every few minutes contain information about aerosol sources and processes. This thesis uses the HR-ToF-AMS measurements in two areas of Greece to quantify the contributions of organic aerosol sources to the corresponding organic aerosol levels. Local and regional air pollution sources were monitored and characterized in two sites during intensive campaigns. The first campaign took place during the fall of 2011 (September 24 to October 23) in Finokalia, Crete, a remote-background coastal site without any major human activity. The aim of the study was to quantify the extent of oxidation of the organic aerosol (OA) during autumn, a season neither too hot nor cold, with reduced solar radiation in comparison to summer. The second one took place during the winter of 2012 (February 26 to March 5), in the third major city of Greece, Patras. The measurements were conducted in the campus of the Technological Educational Institute of Patras (TEI), in order to quantify the severity of the wintertime air pollution problem in the area and its sources. The contributions of traffic and residential wood burning were the foci of that study. The Finokalia site is isolated and far away from anthropogenic sources of pollution, making it ideal for the study of organic aerosol coming from different directions, usually exposed to high levels of atmospheric oxidants. The fine PM measured during the Finokalia Atmospheric Measurement Experiment (FAME-11) by the AMS and a Multi Angle Absorption Photometer (MAAP) was mostly ammonium sulfate and bisulfate (60%), organic compounds (34%), and BC (5%). The aerosol sampled originated mainly from Turkey during the first days of the study, but also from Athens and Northern Greece during the last days of the campaign. By performing Positive Matrix Factorization (PMF) analysis on the AMS organic spectra for the whole dataset the organic aerosol (OA) composition could be explained by two components: a low volatility factor (LV-OOA) and a semi-volatile one (SV-OOA). Hydrocarbon-like organic aerosol (HOA) was not present, consistent with the lack of strong local sources. The second field campaign took place in the suburbs of the city of Patras, 4 km away from the city center during the winter of 2012. During this 10-day campaign, organics were responsible for 70% during the day and 80% during the evening of the total PM1. The OA mean concentration during that period was approximately 20 μg m-3 and reaching hourly maximum values as high as 85 μg m-3. Sulfate ions and black carbon followed with 10% and 7% of the PM1. PMF analysis of the organic mass spectra of PM1 explained the OA observations with four sources: cooking (COA), traffic (HOA), biomass burning (BBOA), and oxygenated aerosol (OOA), related to secondary formation and long range transport. On average, BBOA represented 58% of the total OM, followed by OOA with 18%, COA and HOA, with the last two contributing of the same percentage (12%). / --
68

Laboratory Aerosol Kinetics Studies of the Hydrolysis Reaction of N2O5 Using a Flow Tube Coupled to a New Chemical Ionization Mass Spectrometer

Escorcia, Egda Nadyr 26 July 2010 (has links)
The hydrolysis reaction of N2O5 was investigated at room temperature on two aerosol types using a flow tube coupled to a newly built Chemical Ionization Mass Spectrometer (CIMS). This instrument was fully constructed and optimized during this research period, as well as employed to conduct one of two aerosol studies. The first examined the reaction on ammonium bisulphate aerosols using a new ion detection method, I-•N2O5 cluster formation, which proved to be highly advantageous over the common approach of dissociative charge transfer, yielding a sensitivity for I-•N2O5 of 0.024 Hz/pptv. The uptake coefficients at 30% and 50% relative humidity were 0.0067 ± 0.0002 and 0.0120 ±0.0014, respectively. The second study was performed using a different CIMS previously assembled in the laboratory. In this case, the reaction was investigated on secondary organic aerosols produced through the ozonolysis of α-pinene, and resulted in an uptake coefficient of 8.5x10-5 ± 7x10-6 at 0% relative humidity.
69

Laboratory Aerosol Kinetics Studies of the Hydrolysis Reaction of N2O5 Using a Flow Tube Coupled to a New Chemical Ionization Mass Spectrometer

Escorcia, Egda Nadyr 26 July 2010 (has links)
The hydrolysis reaction of N2O5 was investigated at room temperature on two aerosol types using a flow tube coupled to a newly built Chemical Ionization Mass Spectrometer (CIMS). This instrument was fully constructed and optimized during this research period, as well as employed to conduct one of two aerosol studies. The first examined the reaction on ammonium bisulphate aerosols using a new ion detection method, I-•N2O5 cluster formation, which proved to be highly advantageous over the common approach of dissociative charge transfer, yielding a sensitivity for I-•N2O5 of 0.024 Hz/pptv. The uptake coefficients at 30% and 50% relative humidity were 0.0067 ± 0.0002 and 0.0120 ±0.0014, respectively. The second study was performed using a different CIMS previously assembled in the laboratory. In this case, the reaction was investigated on secondary organic aerosols produced through the ozonolysis of α-pinene, and resulted in an uptake coefficient of 8.5x10-5 ± 7x10-6 at 0% relative humidity.
70

Caracterização dos vinhos Merlot e Cabernet Sauvignon da serra gaúcha através de determinação das razões isotópicas 13C/12C e 18O/16O

Adami, 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 No. of bitstreams: 1 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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