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Dissertations / Theses on the topic 'Ozone'
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Krzyžanková, Anežka. "Studium reakcí kyslíku a ozónu na povrchu konstrukčních materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445144.
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This master's thesis deals with the study of the reactions of the ozone and oxygen with various construction materials. Ozone as an unstable gas tends to decompose spontaneously and this process can be accelerated by reaction with other substances. The aim of this work is to determine the course of ozone's formation and its depletion in after the contact with various substances. Ozone is widely used mainly due to its disinfecting effects. Therefore, the monitoring of these reactions is beneficial for the choosing of ozonizer's material or its accessories. The theoretical part of this work describes the important properties of the ozone, the possibilities of using this gas, various methods of its generation, the influence of gas admixtures and a temperature on its generation and decomposition, the methods of determining the concentration and surface reaction. The dependence of ozone's formation on the size of the reaction space was monitored for either the silicone and Teflon material in the experimental part of the thesis. The length of the hoses was 20-50 cm and the diameter of the inner space was 6 mm for Teflon and 7,99 mm for a silicone. Furthermore, other experiments were performed for the silicone material, where the formation of the ozone was monitored while the oxygen and argon were being used as working gases. The formation and the depletion of the ozone depending on the changes of reaction time were investigated in the third series of experiments. We worked with a ceramic material with two different inner diameters and also with a brass and a stainless steel material in this experiment. The materials were constructed as the tubes of the same length of 54 cm. The ozone generated from the oxygen was enclosed into the reaction tube and the depletion was monitored. The last experiment was focused on the monitoring of the course of ozone's formation in a quartz cuvette influenced by the reaction time and the composition of the working gas. The amount of generated ozone was determined by absorption spectrometry in the all studied cases. The ozone flowing through the system was adsorbed by the surface of the material during the discharge. A mixture of gases (the adsorbed ozone, the oxygen and the argon in various ratios) was present in the sealed reaction space. The Ozone was formed on the surface of the material. The adsorbed ozone decomposed into a molecular and an atomic oxygen. The atomic oxygen reacted with the oxygen molecule occurring in the reaction space. The reaction time leading to the biggest obtained concentration of generated ozone was determined by the experimental data. For most of the materials, the reaction time was about 6 minutes.
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Védlová, Petra. "Tištěný ozonový dozimetr." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240593.
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This diploma thesis deals with ozone measurement methods, especially focusing on opto-chemical methods, when the color change of the sample is examined. Moreover it deals with dyes that are sensitive to ozone and their degradation kinetics. In the experimental part kinetics of dyes Orange I, Orange II and Indigo carmine is examined, These dyes are prepared in the form of ink of different composition. These inks are applied to diverse substrate materials by the material printing method, further by using a Baker film aplicator and in the end by the screen printing method. The properties of the samples are evaluated as well as factors affecting their degradation.
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Yanitska, I. V. "Ozone depletion." Thesis, Сумський державний університет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/34904.
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The ozone layer is a belt of naturally occurring ozone gas that sits 9.3 to 18.6 miles (15 to 30 kilometers) above Earth and serves as a shield from the harmful ultraviolet B radiation emitted by the sun.
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Zaichenko, O., and T. Kostyuchenko. "Ozone holes." Thesis, Видавництво СумДУ, 2004. http://essuir.sumdu.edu.ua/handle/123456789/22823.
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Eriksson, Margareta. "Ozone chemistry in aqueous solution : ozone decomposition and stabilisation." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-303.
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Siddans, Richard. "Height resolved ozone retrievals from the Global Ozone Monitoring Experiment." Thesis, University of Reading, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414562.
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Kilbane-Dawe, Iarla Jonathan. "Ozone trends, Match and the subvortex : studies in stratospheric ozone." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624260.
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Gouraud, Véronique. "Asthme et ozone." Bordeaux 2, 1997. http://www.theses.fr/1997BOR2P015.
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Choe, Kevin Min. "Ozone inactivation of Bacillus cereus spores in ozone demand free water." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0008/MQ34347.pdf.
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Cardelino, Carlos Antonio. "Issues on urban ozone : natural hydrocarbons, urbanization and ozone control strategies." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/25952.
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Grima, N. M. M. "Kinetic and mass transfer studies of ozone degradation of organics in liquid/gas-ozone and liquid/solid-ozone systems." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3351.
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This work was concerned with the determination of mass transfer and kinetic parameters of ozone reactions with four organic compounds from different families, namely reactive dye RO16, triclocarban, naphthalene and methanol. In order to understand the mechanisms of ozone reactions with the organic pollutants, a radical scavenger (t-butanol) was used and the pH was varied from 2 to 9. Ozone solubility (CAL*) is an important parameter that affects both mass transfer rates and chemical reaction kinetics. In order to determine accurate values of the CAL* in the current work, a set of experiments were devised and a correlation between CAL* and the gas phase ozone concentration of the form CAL*(mol/L) = 0.0456 CO3 (g/m3 NTP) was obtained at 20°C. This work has also revealed that t-butanol did not only inhibit hydroxyl radical reactions but also increased mass transfer due to it increasing the specific surface area (aL). Values of the aL were determined to be 2.7 and 3.5 m2/m3 in the absence and presence of t-butanol respectively. It was noticed that the volumetric mass transfer coefficient (kLa) has increased following the addition of t-butanol. Ozone decomposition was studied at pH values of 2 to 9 in a 500 mL reactor initially saturated with ozone. Ozone decomposition was found to follow a second order reaction at pH values less than 7 whilst it was first order at pH 9. When the t-butanol was added, the decomposition of ozone progressed at a lower reaction order of 1.5 for pH values less than 7 and at the same order without t-butanol at pH 9. Ozone decomposition was found significant at high pHs due to high hydroxide ion concentration, which promotes ozone decomposition at high pHs. The reaction rate constant (k) of RO16 ozonation in the absence of t-butanol was determined. The result suggests that RO16 degradation occurs solely by molecular ozone and indirect reactions by radicals are insignificant. The chemical reaction of triclocarban with ozone was found to follow second order reaction kinetics. The degradation of naphthalene using the liquid/gas-ozone (LGO) system was studied. This result showed that hydroxyl radicals seemed to have limited effect on naphthalene degradation which was also observed when a radical scavenger (t-butanol) was used. Reaction rate constants were calculated and were found around 100 times higher than values reported in the literature due to differences in experimental conditions. From the results of the experimental investigation on the degradation of methanol by ozone it was found that the rate constant (k) of the degradation reaction increased at pH 9. The reaction stoichiometry was found to have a value of 1 mol/mol. The two steps of the liquid/solid-ozone (LSO) system were studied on beds of silica gel and a zeolitic material (D915) and the ozone adsorption process was modeled and found that particle rate controls ozone adsorption step but liquid rate controls the water treatment step. Ozone desorption with pure deionised water was studied. The water flow rate was found to accelerate the desorption rates but pH was found to decrease the desorption rates. In contrast, the effect of pH was insignificant in the presence of t-butanol. Determination of the adsorption isotherms for RO16, naphthalene and methanol revealed that RO16 did not exhibit adsorption on silica gel, but both naphthalene and methanol showed adsorption on D915 described by Langmuir model.
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Lemmen, Carsten. "Future polar ozone predictions of Arctic ozone recovery in a changing climate /." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975445626.
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Kovalenko, Katerina. "The importance of the ozone layer and possible effects of ozone holes." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/13070.
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Adachi, Dena. "Virus inactivation by ozone." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58690.pdf.
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Hawker, Victoria. "Mechanisms underlying ozone tolerance." Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413001.
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Simmons, Alison J. "Studies of ozone deposition." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303460.
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SOO, CAROL. "MECHANISMS OF OZONE TOXICITY." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1020710528.
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Katre, Ashwini A. "Ozone and lung fibrosis." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009m/katre.pdf.
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Menezes, Kim Anne. "Bayesian spatial models : applications for tropospheric ozone data /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Jing, Ping. "Isentropic ozone transport across the tropopause in the lower stratosphere and upper troposphere." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131208/unrestricted/jing%5Fping%5F200405%5Fphd.pdf.
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Choi, Yu-Jin. "A study of ground-level ozone over the Baltimore/Washington ozone nonattainment area." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1789.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Chemical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Duncan, Bryan N. "The effects of urban ozone control strategies on northern hemispheric, midlatitude tropospheric ozone." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/25875.
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DI, NOIA ANTONIO. "Application of neural networks to atmospheric ozone retrievals from the ozone monitoring instrument." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2012. http://hdl.handle.net/2108/204185.
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Bocquet, Florence. "Surface layer ozone dynamics and air-snow interactions at Summit, Greenland. Spring and summer ozone exchange velocity and snowpack ozone: The complex interactions." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273683.
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Bittencourt, Gabriela Dornelles. "Influence of the Antarctic Ozone Hole and Atmospheric Dynamics on Ozone in Southern Brazil." Thesis, La Réunion, 2022. http://www.theses.fr/2022LARE0018.
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Le printemps austral dans l'hémisphère sud présente des réductions temporaires de la teneur en ozone principalement dans la région antarctique connue sous le nom de trou d'ozone antarctique (AOH). Cependant, des études montrent une influence dans les régions de latitude moyenne, comme le sud du Brésil, où des jours avec des diminutions temporaires de la colonne d'ozone totale (COT) sont identifiés. L'objectif principal de cette thèse est d'étudier cette influence de l'AOH sur la région sud du Brésil, en utilisant les données de la colonne d'ozone totale et des profils verticaux qui aideront à identifier la hauteur préférentielle à laquelle ces diminutions se produisent dans le sud du Brésil, en plus à analyser le comportement dynamique de l'atmosphère lors de ces événements dans la période de 42 ans de données (1979-2020). La méthodologie utilisée comprend l'analyse des données quotidiennes moyennes de la colonne totale d'ozone à travers des instruments de surface (spectrophotomètre Brewer), des données satellitaires (TOMS et OMI), et de comparer les données de réanalyse de l'ECMWF-ERA5, pour l'identification des événements d'influence de l'AOH sur la région sud du Brésil. L'analyse du contenu vertical des données O3 du satellite TIMED/SABRE fournit des données quotidiennes de 15 a 105 km d'altitude et dispose de 17 années de profils O3 disponibles sur la période de 2002 à 2018. La validation de ces données était nécessaire, et pour cela le réseau SHADOZ de mesures de sondes d'ozone a été utilisé pour effectuer cette validation à travers la saison tropicale au Natal/RN comme référence. Cette validation a montré un bon accord entre les deux instruments, permettant l'utilisation de SABER pour l'analyse des événements d'influence AOH. À partir de là, 102 événements ont été identifiés qui ont influencé Santa Maria/RS avec une diminution temporaire de la teneur en O3 au cours de la période, et avec une chute moyenne entre 24 et 28,1 km d'altitude. Dans l'analyse dynamique, les champs stratosphériques ont montré une augmentation du tourbillon potentiel dans la moyenne des événements, principalement dans les mois de septembre et octobre. Dans la dynamique de la section verticale de l'atmosphère, la présence constante de jets stratosphériques et troposphériques dans la moyenne des événements, indique une forte influence que ces systèmes ont lors de l'occurrence des événements à effet secondaire AOH sur Santa Maria/RSThe austral spring in the Southern Hemisphere presents temporary reductions in ozone content mainly in the Antarctic region known as the Antarctic Ozone Hole (AOH). However, studies show an influence in mid-latitude regions, such as southern Brazil, where days with temporary decreases in the total ozone column (TCO) are identified. The main objective of this thesis is to investigate this influence of AOH on the southern region of Brazil, using data from the total ozone column and vertical profiles that will help to identify the preferential height at which these decreases occur in southern Brazil, in addition to analyzing the atmospheric dynamic behavior during these events in the period 42 years of data (1979 to 2020). The methodology used comprises the analysis of average daily data of the total column of ozone through surface instruments (Brewer Spectrophotometer), satellite data (TOMS and OMI), and to compare reanalysis data from the ECMWF-ERA5, for the identification of events of influence of the AOH on the southern region of Brazil. The analysis of the vertical content of O3 data from the TIMED/SABER satellite provides daily data from 15 to 105 km in height and has 17 years of O3 profiles available in the period from 2002 to 2018. The validation of these data was necessary, and for that the SHADOZ network of ozonesondes measurements was used to carry out this validation through the tropical season in Natal/RN as a reference. This validation showed a good agreement between the two instruments, enabling the use of SABER for the analysis of AOH influence events. From this, 102 events were identified that influenced Santa Maria/RS with a temporary decrease in O3 content during the period, and with an average drop between 24 - 28.1 km in altitude. In the dynamic analysis, the stratospheric fields showed an increase in the potential vorticity in the average of the events, mainly in the months of September and October. In the dynamics of the vertical section of the atmosphere, the constant presence of stratospheric and tropospheric jets in the average of the events, indicates a strong influence that these systems have during the occurrence of the AOH secondary effect events on Santa Maria/RS
A primavera austral no Hemisfério Sul apresenta reduções temporárias do conteúdo de ozônio principalmente na região Antártica conhecida como Buraco de Ozônio Antártico (AOH). Porém, estudos mostram uma influência sob regiões de médias latitudes, como o Sul do Brasil, onde são identificados dias com diminuições temporárias da coluna total de ozônio (CTO). Com isso, o objetivo principal dessa tese é investigar essa influência do AOH sobre a região sul do Brasil, utilizando dados da coluna total de ozônio e de perfis verticais que vão ajudar a identificar a altura preferencial em que essas diminuições ocorrem no sul do Brasil, além de analisar o comportamento dinâmico atmosférico durante esses eventos no período 42 anos de dados (1979 a 2020). A metodologia utilizado compreende a análise de dados médios diários da coluna total de ozônio através de instrumentos de superfície (Espectrofotômetro Brewer), dados de satélites (TOMS e OMI), e para comparação dados de reanálise do ECMWF-ERA5, para a identificação de eventos de influência do AOH sobre a região Sul do Brasil. A análise do conteúdo vertical de O3 dados do satélite TIMED/SABER disponibilizam dados diários de 15 a 110 km de altura e possuem 17 anos de perfis de O3 disponíveis no período de 2002 a 2018. A validação desses dados se fez necessária, e para isso foi utilizada a rede SHADOZ de medidas de ozonesondes para realizar essa validação através da estação tropical em Natal/RN como referência. Essa validação apresentou uma boa concordância entre os dois instrumentos, viabilizando o uso do SABER para as análises dos eventos de influência do AOH. A partir disso, foram identificados 102 eventos que influenciaram Santa Maria/RS com diminuição temporária no conteúdo de O3 durante o período, e com queda média entre 24 e 28,1 km de altitude. Nas análises dinâmicas os campos estratosféricos mostraram o aumento da vorticidade potencial na média dos eventos, principalmente nos meses de setembro e outubro. Na dinâmica do corte vertical da atmosfera a presença constante dos jatos estratosféricos e troposféricos na média dos eventos, indica forte influência que esses sistemas possuem durante a ocorrência dos eventos de efeito secundário do AOH sobre Santa Maria/RS
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Fow, Alista John. "Ozone Depletion and Global Warming." The University of Waikato, 2006. http://hdl.handle.net/10289/2311.
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Abstract This thesis examines global warming and the possible contribution that ozone depletion provides to this warming. An examination is performed to determine the extent of any warming/cooling events within the Earth-atmosphere system. The change in energy corresponding to this warning of the Earth- atmosphere system is estimated as being equivilent to an increase of mean solar input of 0.22W/m2. This is compared to the predicted changes of solar input for the two most common global warming scenarios: greenhouse gases and solar irradiance variance; and for a less well explored scenario, snow-ice albedo change. Examination of ozone depletion data shows that an absence of ozone in the stratosphere produces an increase in UV-B radiation at the surface of the Earth. This increase in UV-B light has not previously been thourougly examined in any of the global warming scenarios. This is presented as a fourth scenario for global warming. An analytical three layer model of the Earth-atmosphere, based on an earlier two layer model, is developed. Using this model it is determined that greenhouse gases, solar irradiance, snow-ice albedo feedback and ozone depletion can cause warming of the Earth's atmosphere. After comparison with other models, a snow-ice albedo mechanism is incorporated into the three layer model. This produces an amplification effect of any warming that occurs. Compared to the observed increase of surface temperature between 1975-2000 of 0.55 K, the model using a snow-ice albedo feedback, produced an increase of temperature of 1.4 K for greenhouse gases, 0.294 K for a solar irradiance increase and 0.119 K caused by a decrease in the ozone layer. Of the greenhouse gas, solar irradiance and ozone depletion scenarios, ozone depletion demonstrates the most realistic relative changes with a cooling of the stratosphere and a warming of the troposphere and Earth's surface as has been observed. It is concluded that ozone depletion is likely for a reasonable part of observed global warming.
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Zhang, Xiao Zhu. "Ozone bleaching of chemical pulp." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0014/NQ38356.pdf.
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Sivaraman, Bhalamurugan. "Ozone formation in icy mantles." Thesis, Open University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.495990.
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In this thesis the results of a detailed experimental study of the chemistry induced by irradiation of ice maniies by electrons and ions are presented. This research is directed towards gaining a better understanding of the mechanisms by which molecules are S3 nthesised in the Interstellar Medium (ISM) and lunar surfaces. Several experiments explored the formation of ozone in such ice mandes, since the ozone in any planetaiy or lunar atmosphere has been suggested as biomarker in die search for life. However recent space missions have revealed ozone on several Samrnian moons and Jupiter's Ganymede. In this thesis we show that ozone is readily produced abiodcally by irradiation of oxygen, carbon dioxide, nitrous oxide and nitrogen dioxide ices. These results have important implications for the use of ozone as a biomarker in the search for life on extraterrestrial planets.
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Kentarchos, Anastasios S. "Background tropospheric ozone over Europe." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361428.
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Umponstira, Chanin. "Ozone and water stress interactions." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341462.
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Jrrar, Amna Fayez Ahmad. "Modelling trends in stratospheric ozone." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615685.
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Lee, Adrian Michael. "Numerical modelling of stratospheric ozone." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627432.
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Centoni, Federico. "Global scale modelling of ozone deposition processes and interaction between surface ozone and climate change." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25454.
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Atmospheric concentrations of surface ozone (O3) are strongly affected by deposition to the biosphere. Deposition processes are very sensitive to turbulence, temperature, relative humidity and soil moisture deficit and are expected to respond to global climate change, with implications for both air quality (e.g. human health) and ecosystem services (e.g. crop yields). In this PhD study, the global chemistry aerosol model UKCA (United Kingdom Chemistry Aerosol model) dry deposition scheme was thoroughly investigated. Some errors in the existing implementation of the current UKCA stomatal resistance and in-canopy aerodynamic resistance terms for O3 and NOw (NO2, PAN, PPAN, MPAN) were identified and corrected (WES scheme). These model corrections led to a decrease of the total annual dry deposition of -150 Tg(O3) yr-1 (-13%) which brings UKCA more in line with multi-model inter-comparison estimates. This was associated with a large increase of surface O3 concentration over land in the Northern Hemisphere (NH) with values up to 12 ppb (+50%) higher on annual average. Many studies have shown that O3 stomatal uptake by vegetation, which is the pathway leading to damage, accounts for 40-60% of total deposition on average. The remaining non-stomatal deposition flux is to external foliar surfaces, and soil. A more mechanistic non-stomatal dry deposition approach along with a scheme to simulate the effect of moisture on foliar surfaces on the stomatal transport (ZHG scheme) was introduced in UKCA to study the relative contributions of O3 flux occurring to stomatal and non-stomatal pathways at the global scale, and to explore the sensitivity of simulated surface O3 and O3 deposition flux. The ZHG scheme, led to significant changes in the O3 dry deposition velocity (Vd) (+40% in the North Hemisphere over boreal forests and -30% over tropical regions on annual average). The results of this study show that the ZHG scheme significantly changes the partitioning between stomatal and non-stomatal O3 flux. The non-stomatal fraction increased throughout the year and considerably during the cooler season and in spring (with maxima values by up to 60% for C3 grass and by up to 70% for needle leaf trees). The performance of both UKCA dry deposition schemes were compared with measurements, focussing on the diurnal and seasonal variations of the dry deposition velocity terms and the partitioning of O3 fluxes between stomatal and non-stomatal sinks. Overall, both UKCA dry deposition schemes capture the diurnal variations of Vd reasonably well. However, this study highlighted difficulties in comparing large grid (~280 x 390 km at mid-latitudes) averaged modelled values with site and vegetation specific characteristics of the measured exchange processes (~1 km2) and the driving meteorological variables. These differences in scale are a large source of uncertainty in the comparison of measured and modelled O3 Vd. Off-line simulation tests conducted on the non-stomatal deposition component with the ZHG scheme demonstrated the importance of modelling some key environmental and meteorological factors accurately (e.g. relative humidity, friction velocity, leaf area index). This was found to be crucial in order to improve O3 Vd model performance as well as improving the representation of specific vegetation properties. A comparison of the modelled global surface O3 concentration against observations both in the NH and SH revealed that the model performs well in the NH using both schemes, capturing the observed surface O3 cycle and the absolute values. The ZHG scheme led to a reduction of the annual bias (up to -13.5% on average) in the NH monitoring sites considered for this study. This is associated with a decrease in O3 deposition simulated with ZHG (as much as of -20% on annual average). By contrast, the seasonal cycle and absolute values of the observed surface O3 are not well reproduced by the model across the SH monitoring sites used in this study and a larger bias was found using the ZHG scheme (60% on average) compared to WES scheme (47% on average), as a consequence of an increase in O3 deposition (as much as of +20% on annual average) calculated with ZHG. A future climate integration for the 2090s using RCP 8.5 scenario was used to investigate the response of UKCA modelled O3 to climate change. The effect of climate change (by altering only the GHG concentrations predicted with RCP 8.5) on the dry deposition sink of O3 was addressed contrasting the two non-stomatal deposition parameterizations, and ignoring the changes in land-use and anthropogenic emissions. The study showed that O3 Vd over land declines from 2000 to 2100, and most strongly over vegetated areas (up to -24% over S. America, -17% over N. America and -10% over Europe). Climate change led to an increase of surface O3 concentration over land (by up to 20%). Whilst the two schemes behave similarly, and an increase in turbulence has been identified as the main driver, the decrease in land Vd is generally stronger in ZHG. This effect is more important over N. America and Eurasia where ZHG exhibits larger differences in deposition compared to WES as a result of changing climate. The increase in surface O3 over Arctic and Antarctic regions shows the effect that changes in O3 deposition might have on the long-range transport of O3. Finally, the influence of climate change on the partitioning of the O3 deposition flux was examined. This analysis revealed that more O3 is predicted to deposit through stomatal pathways with ZHG over N. America, C. Europe and E. Asia (up to +30%) compared to WES as a result of changing climate. Given that ZHG scheme captures the influence of meteorology and changing climate on surface O3 better than WES, it was concluded that modelled surface O3 using ZHG scheme showed a larger sensitivity to a changing climate than WES. These results imply potentially important effects of climate change on tropospheric O3, degrading air quality through the later decades of this century.
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Streibel, Martin Albert Gerhard. "Bestimmung von Ozonabbauraten über der Arktis und Antarktis mittels Ozonsonden- und Satellitendaten." Phd thesis, Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2006/657/.
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Diese Arbeit beschäftigt sich mit der chemischen Ozonzerstörung im arktischen und antarktischen stratosphärischen Polarwirbel. Diese wird durch Abbauprodukte von anthropogen emittierten Fluorchlorkohlenwasserstoffen und Halonen, Chlor- und Bromradikale, verursacht. Studien in denen der gemessene und modellierte Ozonabbau verglichen wird zeigen, dass die Prozeße bekannt sind, der quantitative Verlauf allerdings nicht vollständig verstanden ist.
Die Prozesse, die zur Ozonzerstörung führen sind in beiden Polarwirbeln ähnlich. Allerdings fällt als Konsequenz unterschiedlicher meteorologischer Bedingungen der chemische Ozonabbau im arktischen Polarwirbel weniger drastisch aus als über der Antarktis. Der arktische Polarwirbel ist im Mittel stärker dynamisch gestört als der antarktische und weist eine stärkere Jahr-zu-Jahr Variabilität auf. Das erschwert die Messung des chemischen Ozonabbaus. Zur Trennung des chemischen Ozonabbaus von der dynamischen Umverteilung des Ozons im arktischen Polarwirbel wurde die Matchmethode entwickelt. Bei dieser Methode werden Luftpakete innerhalb des Polarwirbels mehrfach beprobt, um den chemischen Anteil der Ozonänderung zu quantifizieren. Zur Identifizierung von doppelt beprobten Luftpaketen werden Trajektorien aus Windfeldern berechnet. Können zwei Messungen im Rahmen bestimmter Qualitätskriterien durch eine Trajektorie verbunden werden, kann die Ozondifferenz zwischen beiden Sondierungen berechnet und als chemischer Ozonabbau interpretiert werden. Eine solche Koinzidenz wird Match genannt. Der Matchmethode liegt ein statistischer Ansatz zugrunde, so dass eine Vielzahl solcher doppelt beprobter Luftmassen vorliegen muss, um gesicherte Aussagen über die Ozonzerstörung gewinnen zu können. So erhält man die Ozonzerstörung in einem bestimmten Zeitintervall, also Ozonabbauraten. Um die Anzahl an doppelt beprobten Luftpackten zu erhöhen wurde eine aktive Koordinierung der Ozonsondenaufstiege entwickelt.
Im Rahmen dieser Arbeit wurden Matchkampagnen während des arktischen Winters 2002/2003 und zum ersten Mal während eines antarktischen Winter (2003) durchgeführt. Aus den gewonnenen Daten wurden Ozonabbauraten in beiden Polarwirbeln bestimmt. Diese Abbauraten dienen zum einen der Evaluierung von Modellen, ermöglichen aber auch den direkten Vergleich von Ozonabbauraten in beiden Polarwirbeln.
Der Winter 2002/2003 war zu Beginn durch sehr tiefe Temperaturen in der mittleren und unteren Stratosphäre charakterisiert, so dass die Matchkampagne Ende November gestartet wurde. Ab Januar war der Polarwirbel zeitweise stark dynamisch gestört. Die Kampagne ging bis Mitte März. Für den Höhenbereich von 400 bis 550 K potentieller Temperatur (15-23 km) konnten Ozonabbauraten und der Verlust in der Gesamtsäule berechnet werden. Die Ozonabbauraten wurden in verschiedenen Tests auf ihre Stabilität überprüft.
Der antarktische Polarwirbel war vom Beginn des Winters bis Mitte Oktober 2003 sehr kalt und stellte Ende September kurzzeitig den Rekord für die größte bisher aufgetretene Ozonloch-Fläche ein. Es konnten für den Kampagnenzeitraum, Anfang Juni bis Anfang Oktober, Ozonabbauraten im Höhenbereich von 400 bis 550 K potentieller Temperatur ermittelt werden. Der zeitliche Verlauf des Ozonabbaus war dabei auf fast allen Höhenniveaus identisch. Die Zunahme des Sonnenlichtes im Polarwirbel mit der Zeit führt zu einem starken Anwachsen der Ozonabbauraten. Ab Mitte September gingen die Ozonabbauraten auf Null zurück, da bis zu diesem Zeitpunkt das gesamte Ozon zwischen ca. 14 und 21 km zerstört wurde.
Im letzten Teil der Arbeit wird ein neuer Algorithmus auf Basis der multivariaten Regression vorgestellt, mit dem Ozonabbauraten aus Ozonprofilen verschiedener Sensoren gleichzeitig berechnet werden können. Dabei können neben der Ozonabbaurate die systematischen Fehler zwischen den einzelnen Sensoren bestimmt werden. Dies wurde exemplarisch am antarktischen Winter 2003 für das 475 K potentielle Temperatur Niveau gezeigt. Neben den Ozonprofilen der Sonden wurden Daten von zwei Satellitenexperimenten verwendet. Die mit der multivariaten Matchtechnik berechneten Ozonabbauraten stimmen gut mit den Ozonabbauraten der Einzelsensor-Matchansätze überein.
The subject of this thesis is the destruction of ozone in the stratospheric polar vortex of the Arctic and Antarctic. It is caused by decomposition products of anthropogenic emitted Chlorofluorocarbons and Halons, radicals of chlorine and bromine. Studies which are dealing with the comparison of measured and modelled ozone loss show that the processes are known but that the quantitative development is not fully understood yet.
The processes that lead to ozone destruction are similar in both polar vortices. But as a consequence of different meteorological conditions the chemical ozone loss in the arctic polar vortex is less dramatic than over the Antarctic. On average the Arctic polar vortex is stronger perturbed and exhibit a stronger annual variability. In order to distinguish between chemical ozone loss and the dynamical redistribution of ozone in the Arctic vortex the Match method was developed. Air parcels in the polar vortex are probed several times in order to quantify the chemical change in ozone. To identify those air parcels trajectories are calculated using wind fields. When it is possible to connect two measurements by a trajectory within certain quality criteria the difference in ozone can be calculated and is interpreted as chemical ozone loss. Such a coincidence is called a Match. The Match method is a statistical approach which needs many of those doubly probed air parcels in order to draw significant conclusions about the destruction of ozone. So the ozone destruction can be calculated for a certain period in time which gives ozone loss rates. In order to enhance the number of doubly probed air masses an active coordination was established.
Within the scope of the thesis Match campaigns were performed during the Arctic winter 2002/2003 and for the first time during the Antarctic winter 2003. The achieved data was used in order to determine ozone loss rates in both polar vortices. The loss rates serve for the evaluation of numerical models but allow as well the direct comparison of ozone loss rates of both polar vortices.
The beginning of the winter 2002/2003 is characterized by very low temperatures in the middle and lower stratosphere. Hence, the Match campaign started at the end of November. From January on the polar vortex was strongly dynamically disturbed at certain times. For the height region of 400 to 500 K potential temperature (15-23 km) ozone loss rates and the column loss were determined. The robustness of the ozone loss rates was checked with a variety of different tests.
From beginning of the winter until October 2003 the Antarctic polar vortex was very cold and the expansion of the ozone hole area reached record values in late September. From the beginning of June until the beginning of October ozone loss has been calculated in a height region from 400 to 550 K potential temperature. The development of the ozone loss was almost identical on the different height levels. The increase in sunlight led to an increase in ozone loss rates. From mid September the ozone loss rates decreased rapidly and the ozone was completely destroyed between approx. 14 and 21 km.
In the last part of the thesis a new algorithm is presented which is based on a multivariate regression in order to calculate ozone loss rates from ozone profiles made by different sensors. At the same time the systematic error between different sensors has to be considered. As an example the approach is shown for the Antarctic Winter 2003 on the 475 K potential temperature level. Beside the ozone profiles from the sondes, data from two satellites experiments have been used. The agreement between the ozone loss rates calculated by the multivariate regression method and those calculated by the single match approach is very good.
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Kremser, Stefanie [Verfasser]. "Improved understanding of polar ozone chemistry and the future of the Antarctic ozone hole / Stefanie Kremser." Berlin : Freie Universität Berlin, 2011. http://d-nb.info/1025938852/34.
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Atkinson, Roger John. "An observational study of the austral spring statosphere : dynamics, ozone transport, and the "ozone dilution effect"." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12448.
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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1993.Includes bibliographical references (p. 367-385).
by Roger John Atkinson.
Sc.D.
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Wijnbladh, Erik. "Ozone Technology for Sludge Bulking Control." Thesis, Uppsala University, Department of Earth Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88830.
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Slamsvällning orsakar stora problem i avloppsreningsverk med biologisk rening i aktivt slamprocesser. Slamsvällning orsakas av filamentösa (trådformiga) bakterier, som inverkar negativt på slammets sedimenteringsegenskaper.
Himmerfjärdens vattenreningsverk har drabbats av detta problem som leder till ett stabilt lager av slam på ytan av sedimenteringsbassängen som inte sedimenterar.
För att lösa detta problem behandlades returslammet från sedimenteringsbassängen med ozon för att minska mängden filamentösa bakterier i returslamflödet. Ozon är en starkt oxiderande gas, som är väl användbar för icke-specifik bekämpning av slamsvällning. När ozon kommer i kontakt med den filamentösa bakteriens cellvägg penetreras det in i cellen, varvid cellen lyserar.
Ozonbehandlingen resulterade i en förminskning av antalet filamentösa bakterier. Ozonbehandling av returslam förbättrade sedimenteringsegenskaperna hos svällande slam utan att påverka andra viktiga mikrobiologiska processer t.ex. nitrifikation.
Bulking sludge causes major problems in wastewater treatment plants that deal with biological nutrient removal in activated sludge processes. Bulking sludge is caused by filamentous bacteria, which have a negative impact on the sludge settling properties.
Himmerfjärden wastewater treatment plant suffers from this type of problem with bulking sludge which creates a stable layer at the surface that does not settle in the clarifier.
In order to solve this problem, on site generated ozone was used to decrease the amount of filamentous bacteria in the return activated sludge flow. Ozone is a strong oxidant is suitable for non-specific bulking control. It stresses the filamentous bacteria causing inactivation through cell wall disintegration.
The ozone treatment resulted in decreased abundance of filamentous bacteria. Ozone treatment of the recycled activated sludge improves the settling properties of bulking sludge, without interfering with other important microbiological processes e.g. nitrification.
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Iglesias, Suarez Fernando. "Stratospheric ozone in the Earth system." Thesis, Lancaster University, 2017. http://eprints.lancs.ac.uk/125703/.
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Ozone in the stratosphere protects life on Earth by absorbing much of the ultraviolet solar radiation, as well as being a major source of ozone to the troposphere. A number of factors can influence stratospheric ozone levels and explain past, present and future changes. While there is a large literature exploring changes in stratospheric ozone due to, for example, ozone depleting substances (ODSs) and climate change, the study of its interactions with the rest of the Earth system is relatively recent. The work presented in this thesis investigates changes in stratospheric ozone and its links with other elements of the Earth system (tropospheric chemical composition and climate), using observations, a global chemistry-climate model (CESM1-WACCM), and existing multi-model output. This work evaluates past changes and explores future evolution of stratospheric ozone and associated climate impacts using multi-model output (ACCMIP simulations) from the pre-industrial period to the end of the 21st century. ACCMIP multi-model mean total column ozone trends compare favourably against observations. These models show a strong link between the Antarctic ozone hole and surface climate, which demonstrates that stratospheric ozone changes are coupled with the troposphere. A series of sensitivity simulations is conducted to investigate multi-decadal variability. A striking finding is that low frequency variability of ozone in the tropical middle stratosphere resembles multi-decadal climate variability in Pacific Ocean sea surface temperatures. This analysis also shows that internally generated climate variability is the leading factor explaining recent negative trends of mid-stratospheric tropical ozone. Finally, an additional set of sensitivity simulations is performed to quantify future radiative forcing between 2000s and 2100s that results from changes in ozone due to climate change, ODSs and methane concentrations. These results highlight the importance of stratosphere-troposphere exchange, as well as the key role of the stratosphere controlling the tropospheric ozone forcing.
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Huang, Guangming. "Dielectric barrier discharges for ozone generation." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27626.
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Non-thermal plasma discharges, particularly dielectric barrier discharges (DBDs), are the most common method of ozone generation. The aim of this research was to optimize the micro-discharges in DBDs, to improve ozone generation efficiency. The electrical characteristics of DBDs were researched, and the effects of the physical and electrical parameters of DBDs on ozone generation were investigated. Four DBD based ozone reactors, including plate configuration and cylindrical configuration, were designed and developed. Three major energization modes, including transient (40 ms) AC power supply, continuous AC power supply and pulsed power supply, were used for the investigation of ozone generation performance. Under transient AC energisation in oxygen, it was found that the ozone generation efficiency at 2 bar absolute was 217 g/kWh, increased by 31% compared with that at 1 bar absolute. The ozone generation efficiency was found to increase with decreasing E/N in the range from 126 Td to 185 Td. Under continuous AC energisation, the ozone concentration was found to increase as the gas flow rate decreased (from 1 L/min to 0.4 L/min) or applied voltage was increased (from 3.5 kV to 6 kV). Under optimized conditions, the highest ozone concentration obtained was 271 g/Nm3, which is promising in comparison with previously-published data. The ozone generation efficiency was found to reduce as the ozone concentration increased above 30 g/Nm3. Furthermore, it was found that the AC energization frequency had no obvious effect on the behaviour of micro-discharges, or on the ozone generation efficiency. Pulsed DBDs for ozone generation was found to be less efficient than continuous AC energisation, for the conditions investigated herein. This research has achieved the desired combination of high ozone generation efficiency at high ozone concentration (>150 g/Nm3), based on DBDs The curve of ozone generation efficiency versus ozone concentration achieved shows more efficient performance than that in the literature: at the typical industrial ozone concentration of 150 g/Nm3 for waste water treatment, the ozone generation efficiency in this work was ~8.2 kWh/kg, ~20% higher than that in the literature.
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Martin, Fabrine. "Ozone troposphérique : impact sur la santé." Lille 2, 1992. http://www.theses.fr/1992LIL2P013.
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Newchurch, M. J., Lane Bishop, Derek Cunnold, Lawrence E. Flynn, Sophie Godin, Stacey Hollandsworth Frith, Lon Hood, et al. "Upper-stratospheric ozone trends 1979-1998." American Geophysical Union, 2000. http://hdl.handle.net/10150/624006.
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Extensive analyses of ozone observations between 1978 and 1998 measured by Dobson Umkehr, Stratospheric Aerosol and Gas Experiment (SAGE) I and II, and Solar Backscattered Ultraviolet (SBUV) and (SBUV)/2 indicate continued significant ozone decline throughout the extratropical upper stratosphere from 30–45 km altitude. The maximum annual linear decline of −0.8±0.2 % yr−1 (2σ) occurs at 40 km and is well described in terms of a linear decline modulated by the 11-year solar variation. The minimum decline of −0.1±0.1% yr−1 (2σ) occurs at 25 km in midlatitudes, with remarkable symmetry between the Northern and Southern Hemispheres at 40 km altitude. Midlatitude upper-stratospheric zonal trends exhibit significant seasonal variation (±30% in the Northern Hemisphere, ±40% in the Southern Hemisphere) with the most negative trends of −1.2% yr−1 occurring in the winter. Significant seasonal trends of −0.7 to −0.9% yr−1 occur at 40 km in the tropics between April and September. Subjecting the statistical models used to calculate the ozone trends to intercomparison tests on a variety of common data sets yields results that indicate the standard deviation between trends estimated by 10 different statistical models is less than 0.1% yr−1 in the annual-mean trend for SAGE data and less than 0.2% yr−1 in the most demanding conditions (seasons with irregular, sparse data) [World Meteorological Organization (WMO), 1998]. These consistent trend results between statistical models together with extensive consistency between the independent measurement-system trend observations by Dobson Umkehr, SAGE I and II, and SBUV and SBUV/2 provide a high degree of confidence in the accuracy of the declining ozone amounts reported here. Additional details of ozone trend results from 1978 to 1996 (2 years shorter than reported here) along with lower-stratospheric and tropospheric ozone trends, extensive intercomparisons to assess relative instrument drifts, and retrieval algorithm details are given by WMO [1998].
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Siddiqui, Mohamed Shakeel. "Ozone-bromide interactions in water treatment." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185847.
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Ozonation of drinking waters, particularly as a preoxidant, is becoming a widespread practice. Ozone is a powerful oxidant and reacts with many of the natural constituents present in water. The presence of bromide ion in water can lead to the formation of brominated disinfection by-products upon ozonation. The existence of brominated by-products in a public water supply could be of public health concern since some of them have been shown to be mutagenic. Production of both organic and inorganic by-products upon ozonation of waters containing bromide ion was investigated. Organic by-products identified include bromoform, dibromoacetonitrile (DBAN), and 1,1(DBAA); inorganic by-products identified include bromate, hypobromous acid and hypobromite ion. Formation of by-products is a function of bromide ion concentration, the source and concentration of humic substances, pH, ozone dose, temperature, alkalinity and reaction time. Bromoform concentration ranged from 5 to 60 $\mu$g/L and total organic bromine (TOBr) concentration varied from 15 to 150 $\mu$g/L for a bromide concentration ranging from 0.5 to 1.5 mg/L. TOBr concentrations were much higher than bromoform indicating that bromoform constitutes only a fraction of the pool of brominated DBP material. Bromate threshold levels were shown to vary according to precursor source and pH level. At pH 7.5 bromide threshold concentrations for bromate were higher than at pH 8.5; the exact opposite case was observed for bromoform. Ionic strength had no significant effect on the formation of by-products whereas an increase in alkalinity resulted in decreased amounts of by-products. Temperature effects are manifested in two different ways: (i) the water temperature at which ozonation was carried out versus (ii) the subsequent incubation temperature. While enhanced precursor oxidation was observed at higher ozonation temperatures, the partial oxidation by-products varied in their reactivity in forming brominated by-products upon incubation. An increase in incubation temperature from 20 to 30$\sp\circ$C produced about a 30% increase in bromoform where as an increase in ozonation temperature resulted in a 20% increase in bromoform. Results of this research indicate that control of by-products can be effected by using PEROXONE (hydrogen peroxide plus ozone) or ammonia. PEROXONE produced 55% less organic by-products at the cost of a 25% increase in bromate. Ammonia addition resulted in a 30% decrease of both organic and inorganic by-products.
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Guthrey, Delparde Raleigh. "Time series analysis of ozone data." CSUSB ScholarWorks, 1998. https://scholarworks.lib.csusb.edu/etd-project/1788.
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Sloan, Daniela. "Effects Of Ozone On Blood Components." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1772.
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Previous studies on the medical use of ozone therapies show a very diverse array of results, from ozone reducing the amount of HIV virus in the blood, to no effect, to causing the death of several patients due to pulmonary embolism and infections. However, ozone therapies are widely used in Europe and considered medically safe. In the U.S., doctors in 28 states use ozone therapies.
The objectives of this study were to investigate the effects of medical grade ozone at varying concentrations used in ozone therapies. These were achieved by evaluating the C-reactive protein, erythrocyte sedimentation rate, total reduced and oxidized glutathione content of erythrocytes which were all markers used to determine ozone injury/inflammation.
Despite the fact that ozone is a very strong oxidant, previous research indicates that depending on the dose and the health status of the biological system, sometimes ozone can act as an antioxidant.
The medical exposure range for ozone is between 20-80 mg/ml with an average of 50 mg/ml. The concentrations used in this study were 20, 40, 80 and 160 mg/ml. Ozone was generated in the "Breath Lab" at USF from medical grade oxygen obtained through electrical corona arc discharge using an OL80C ozone generator. De-identified blood samples of 10 ml blood/sample containing EDTA as anticoagulant were obtained from the James A. Haley VA Hospital patients. Equal volumes of blood and ozone gas mixture were allowed to mix in ozone-resistant syringes prior to dividing each sample into three parts, one for each corresponding parameter to be studied. The C-reactive protein was analyzed through ELISA using the colorimetric method available from Helica Biosystems; erythrocyte sedimentation rate was measured in graduated sedimentation tubes; the total reduced glutathione (GSH) and oxidized glutathione (GSSG) content of erythrocytes was determined according to the colorimetric method developed by the Oxford Biomedical Research.
Overall, the concentrations of ozone used did not have a statistically significant effect on the parameters investigated. However, a small percentage of the blood samples showed an improvement in the parameters studied, especially at the highest ozone concentration.
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Pirani, S. M. G. "APPLICATION OF OZONE IN FOOD INDUSTRIES." Doctoral thesis, Università degli Studi di Milano, 2011. http://hdl.handle.net/2434/153539.
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Ozone (O3) is a strong antimicrobial agent with numerous potential applications in the food industry. High reactivity, penetrability and spontaneous decomposition to a nontoxic product (O2) make ozone a viable disinfectant for ensuring the microbiological safety of food products. Ozone has been used for decades in many countries and recently, the generally recognized as safe (GRAS) status of this gas has been reaffirmed in the United States. Ozone, in the gaseous or aqueous phases, is effective against the majority of microorganisms tested by numerous research groups. Relatively low concentrations of ozone and short contact time are sufficient to inactivate bacteria, molds, yeasts, parasites and viruses. Ozone applications in the food industry are mostly related to decontamination of environments and water treatment. Moreover, ozone has been used with success to inactivate contaminant microflora on meat, poultry, eggs, fish, fruits, vegetables and dry foods. The gas also is useful in detoxification and elimination of mycotoxins and pesticide residues from some agricultural products. Excessive use of ozone, however, may cause oxidation of some ingredients on food surface.
The aim of this work was to investigate the real potentiality of gaseous ozone in food industries. Ozone was tested:
- as a disinfectant in meat industry;
- as an alternative method for mites control on meat stored products;
- to reduce extraneous molds on the surface of meat products.
It was also conducted a preliminary investigation on the possible surface oxidation of stored products treated with low concentration of ozone.
The present study shows that gaseous ozone can effectively reduce spoilage microorganisms (Ps. fluorescens), fecal contaminants (E. coli) and food-borne pathogens (L. monocytogenes, B. cereus, S. aureus). It can be used for the disinfection of processing equipment and environment in food industries. Additionally, gaseous ozone might be effective in controlling mites or extraneous molds on meat stored products. Preliminary study show that low ozone treatments of meat stored products did not effect surface oxidation. The studies have shown that ozone can be used with good results both for the sanitation of the environment both for prevention and decontamination of stored product surface. Many people are critical of the use of ozone as it is an irritating substance; it can be felt at low concentrations and can even be poisonous at higher concentrations. Despite such reservations, it must be said that when used under controlled conditions, it is an effective and totally safe disinfectant.
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Yang, Qing. "Derivation of tropospheric column ozone using the TOR approach and mapping technique." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19748.
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Thesis (Ph.D)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2008.Committee Chair: Derek M. Cunnold; Committee Member: Michael Bergin; Committee Member: Ray Wang; Committee Member: Robert Black; Committee Member: Yuhang Wang.
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Bao, Xiaoping. "Variation of the stratospheric ozone layer height and the quasi-biennial oscillation." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/27999.
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Preston, Katherine Elizabeth. "The retrieval of NOâ†2 vertical profiles from ground-based twilight UV-visible absorption measurements." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243236.
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Mendes, João Filipe da Silva. "Ozonoterapia intra-articular em boletos de cavalos com osteoartrite : quais os seus efeitos melhoradores da patologia?" Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/14903.
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Dissertação de Mestrado Integrado em Medicina VeterináriaA osteoartrite é a principal causa de claudicação na espécie equina, sendo um factor limitante sobretudo para cavalos de desporto. Existem inúmeras formas de tratamento da osteoartrite (OA), sendo a corticoterapia a mais utilizada. O ozono é uma molécula com inúmeras acções terapêuticas de elevado interesse na medicina, sobretudo devido à escassa ocorrência de efeitos secundários. A ozonoterapia é um tratamento que tem sido um sucesso relativamente recente na Medicina Humana, tendo já sido também instaurada na Medicina Veterinária com bons resultados. Este trabalho engloba um estudo experimental, em que foram feitas administrações de Ozono intra-articular em boletos de cavalos com osteoartrite na mesma articulação. Os cavalos que foram seleccionados para o estudo tinham vários requisitos a cumprir, entre eles, o mais importante é que tinham de ter uma claudicação com origem num boleto e devido a osteoartrite. Tal requisito deveu-se ao facto de o objectivo principal do estudo se basear na avaliação da melhoria da claudicação, após o tratamento com ozono. Após terminado o estudo, os resultados foram satisfatórios ao revelarem melhorias em todos os cavalos intervenientes no estudo, não só a nível da dor que estes exibiam e se revelava na claudicação mas também a nível da inflamação articular. Podemos assim concluir que a Ozonoterapia intra-articular em equinos pode vir a ser uma alternativa cada vez mais a ter em conta.
ABSTRACT - INTRA-ARTICULAR OZONE THERAPY IN FETLOCKS OF HORSES WITH OSTEOARTHRITIS: WHICH ARE ITS IMPROVING EFFECTS IN THE DISEASE? - Osteoarthritis is the main cause for lameness in the equine species, as well as a restrictive factor mainly for sport horses. There are numerous treatment methods when it comes to osteoarthritis (OA), but corticotherapy is the most commonly used. The ozone is a molecule with several and highly relevant therapeutic uses in medicine, above all because the side effects are rare. Ozone therapy has been, therefore, a relatively recent success in human medicine, and it has also already been introduced in veterinary medicine with good results. This thesis includes an experimental study in which several administrations of intra-articular ozone in fetlocks of horses with osteoarthritis were made. The horses selected for this study had to comply to certain requisites, among which the most important was the fact that they had to show a lameness caused by osteoarthritis and originated in one of the fetlocks. This requisite was important because the main goal of the study was based on assessing the improvement in lameness after the treatment with ozone. After the end of the study, the results were satisfactory and revealed improvement in all the horses treated, not only in terms of the pain level each one of them presented and was evident in the lameness, but also when it came to articular inflammation. We can thus conclude that intra-articular ozone therapy in equines can become a more and more valid alternative.
N/A
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Weiss, Andrea K. "Anthropogenic and dynamic contributions to ozone trends of the Swiss total ozone, umkehr and balloon sounding series /." [S.l.] : [s.n.], 2000. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13635.
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