Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 3 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.

The topic of the thesis is determination of concentration of dissolved solids in water and seasonal changes in surface water chemistry for specific affluents of Orlík water reservoir. Water samples were collected on regular basis and analysed in a laboratory during one season (November 2014 - November 2015). The thesis is focused on monitoring of changes in phosphate and nitrate concentrations, in particular. The results of analysis indicate that measured concentrations of substances at monitored locations reflect generally measured data within the region. Concentrations of NO3-N peak in winter to early spring seasons, therefore seasonal changes do occur; differences between locations have not been proven statistically. As for the parameter PO4-P within locations downstream pond systems no significant statistic differences were identified. Values of PO4-P concentration are not primarily associated with agricultural activities but rather with local sources existing within the catch basin. It has been concluded from testing water quality upstream and downstream fish ponds that pond management had no impact on quality of water within the monitored locations in 2015; respectively no additional phosphor and nitrogen load was imposed on Orlík water reservoir

The master thesis deals with influence of system of water reservois and farming on suface water quality in catchment Košín stream in the Tabor region. There were investigated effect on suface water quality of several watercourses flowing through farmland with markedly different land cover, farming, size of catchment area and different water reservoirs. The fundamental hydrochemical parameters such as content of nutrient, inorganic and organic carbon and undissolved substances were monitored. The water samples were collected from permanent sampling points during the growing season. The investigated compounds were determined in the laboratory by titration, gravimetry and spectrophotometry. Mean, median, interquartile range were determined within the basic descriptive statistics and the data were statistically processed by nonparametric tests. Results showed particularly significant influence of the littoral vegetation and wide strips of tree vegetation as an effective filter, which prevent pollution of surface water by nutrient runoff. In some cases, the land cover was reflected positive impact of vegetation on reducing contamination of the water above the level specified by legislation, therefore vegetation is great importance in the fight pollution of waterways. From the obtained data it is obvious that influence of anthropogenic pollution on surface water is very important, but appropriate land cover can minimalize this impact.

L'activité agricole est, depuis toujours, une source de pollution pour l'eau. Ce lien s'est intensifié avec la mise en place d'une Politique agricole commune à l'échelle de l'Union européenne. En effet la Politique agricole commune s'est construite sur le productivisme en optimisant le rendement des terres, notamment par l'utilisation d'intrants chimiques et naturels, ce qui fut particulièrement préjudiciable pour la ressource hydrique.Cependant, un certain nombre de réformes ainsi qu'une législation et une fiscalité spécifiques se sont érigées dans le but de limiter les effets néfastes de l'agriculture sur la ressource hydrique ; or ces instruments juridiques et institutionnels se sont avérés peu efficaces. Dès lors, les pouvoirs publics se sont employés à responsabiliser les auteurs de telles pollutions à travers un régime de responsabilité approprié. En dépit de ces efforts, le caractère diffus de la pollution de l'eau a constitué un obstacle majeur à l'application d'un tel régime aux pollutions d'origine agricole.Aussi, les pouvoirs publics n'ont d'autre choix que celui de se tourner vers des instruments juridiques plus souples qui permettent d'associer le pollueur aux différentes mesures de lutte contre la pollution de l'eau, notamment à travers la participation et la contractualisation. / Farming has always been a source of pollution for water. This link has been reinforced by establishing a common Agricultural control Policy in the EU. In fact the common Agricultural Policy is based on productivisme optiminzing the yield of land by using manure as well as fertilizers, polluting water to a High degree.However some reforms and a specific tax legislation have been created in order to reduce harmful effects on agriculture and on water ressources unfurtunately these legal and institutionnal instruments have proved ineffective.Therefore governements have sought to make farmers aware of there responsabilities with regards to pollution. Despite these efforts, the diffuse nature of water pollution has been obstacle to the implementation of such a regime agricultural pollution.Consequently goverments have no choice but to turn to more flexible instruments that allow polluters to be associated to the various mesasures taken to avoid the pollution of water, particurly by getting polluters involved in the procès and making them signe contracts.

En France, il est envisagé de stocker en formation géologique profonde les déchets radioactifs vitrifiés à haute activité et vie longue dans un conteneur en acier inoxydable chemisé par un surconteneur en acier non allié. Les principaux produits de corrosion attendus à la surface de ce dernier, i.e. la sidérite (FeIICO3) et la magnétite (FeIIFeIII2O4), jouent un rôle protecteur contre la corrosion en tant que couche passivante. Ce travail de thèse visait à étudier l’influence des groupes métaboliques bactériens réducteurs du fer ferrique (IRB) et des nitrates (NRB) sur les transformations de ces produits de corrosion en anoxie. Des souches modèles de NRB (Klebsiella mobilis) et IRB (Shewanella putrefaciens) ont, dans un premier temps, été incubées en présence de suspension de sidérite ou de magnétite, afin d’exacerber les processus de transformation du fer du fait d’une surface spécifique élevée, puis dans un second temps, en présence de films électrogénérés de ces produits pour se rapprocher des conditions d’un acier non allié corrodé en anoxie. Ces souches bactériennes sont capables de transformer la sidérite et la magnétite par des processus microbiens directs ou indirects et de conduire à la formation de rouille verte carbonatée (FeII4FeIII2(OH)12CO3). Ce composé occupe une place centrale dans le cycle biogéochimique du fer en anoxie en tant que transitoire commun à plusieurs réactions microbiennes mobilisant le fer sous deux états d’oxydation différents FeII et FeIII. L’originalité de ce travail de thèse est donc de montrer que des métabolismes bactériens inaccoutumés tels que les NRB ou les IRB sont susceptibles de jouer un rôle dans les processus de biocorrosion / Radioactive waste is one of the major problems facing the nuclear industry. To circumvent this issue France plans to store vitrified high-level nuclear waste in a stainless steel container, placed into a non-alloy steel overpack, at a depth of 500m in an argillaceous formation. The main iron corrosion products formed at the surface of the non-alloy steel are siderite (FeIICO3) and magnetite (FeIIFeIII2O4). These compounds are formed in the anoxic conditions present in the nuclear waste repository and play a protective role against corrosion as a passive layer. This work aims to investigate the activity of nitrate-reducing bacteria (NRB, Klebsiella mobilis) and iron-reducing bacteria (IRB, Shewanella putrefaciens) during the transformation of siderite and magnetite, especially those involved in anoxic iron biogeochemical cycle. Klebsiella mobilis and Shewanella putrefaciens were first incubated with siderite or magnetite suspensions (high surface specific area) in order to exacerbate the microbial iron transformation, subsequently incubated with a magnetite/siderite film synthesized by anodic polarization at applied current density. The transformation of siderite and magnetite by direct or indirect microbial processes led to the formation of carbonated green rust (FeII4FeIII2(OH)12CO3). As a transient phase shared by several bacterial reactions involving FeII and FeIII, this compound is the cornerstone of the anoxic iron biogeochemical cycle. The novelty of this thesis is the consideration of bacterial metabolisms of NRB and IRB often overlooked in biocorrosion processes

The aim of this diploma thesis was a statistical evaluation of the impact of farming methods and the land cover on hydrochemical parameters of surface waters drainage patterns in Novohradské mountains and identify the possible impact of agriculture on the valuesof these parameters. The area for the evaluation is consist of lower and upper parts of the basin of Pasecký, Bedřichovský and Váčkový stream. Sampling sites include agriculturally cultivated land, but also forest ecosystems. The work is mainly focused on the following parameters: conductivity, nitrate nitrogen (N-NO3-), suspended solids (NL105) and phosphate phosphorus (P-PO43-), which are parameters causing eutrophication of water. The parameters changes were analysed for the years 2014 - 2017. Significant differences were observed in the all three streams in the water chemisms between upper and lower parts of the watersheds of conductivity and nitrate nitrogen (N-NO3-). The results confirmed that the farming has a significant influence on the water quality in the Pasecký, Bedřichovský and Váčkový stream although it is an extensive farming.

Submitted by Maike Costa (maiksebas@gmail.com) on 2017-02-24T14:06:25Z No. of bitstreams: 1 arquivo total.pdf: 3861832 bytes, checksum: 51f845d5047e9aaddd5d14c6395b40a2 (MD5) / Made available in DSpace on 2017-02-24T14:06:25Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 3861832 bytes, checksum: 51f845d5047e9aaddd5d14c6395b40a2 (MD5) Previous issue date: 2015-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Human umbilical cord vessels (HUCV), often considered biological waste, are good models for evaluation of vasoactive substances. The effect of glyceryl trinitrate (GTN) has been characterized in several animal blood vessels, but this nitrate presents little effect on HUCV. The tetrahydrofurfuryl nitrate (NTHF) and 13-cis-9-octadecanoate acetate nitrate (NCOE) are nitric oxide (NO) donors, whose effect has been characterized in animal vessels. 1,2-bis (tetrahydrofuran-2-yl) ethane-1,2-diildinitrato (BIS-NTHF) is a novel compound (two molecules of NTHF) that has no pharmacological studies. The aim of this study was to implement and standardize the technique involving HUCV, and characterize the effect of these four organic nitrates both in artery (HUA) and vein (HUV) rings isolated from umbilical cord. The standardization of the technique showed that 3g and 3h are, respectively, the ideal voltage and time to experiment with the umbilical vessels, besides the fact that it presents a spontaneous decrease both basal tone as the contractile. The study of nitrates showed that these compounds have relaxed the basal tone of HUCV. All nitrate induced vasorelaxation in both umbilical vessels pre-contracted with serotonin (5-HT), with maximum effects than 90%, and more effectively in relaxing HUA than HUV. In this situation, GTN was the most potent nitrate in causing vasodilation, BIS NTHF presented an intermediate power value, while NCOE and NTHF were less potent in relaxing HUV and HUA, respectively. When HUA rings were pre-contracted with KCl 60 mM, there was an attenuation of vasodilation promoted by nitrates. GTN and the NTHF also showed decreased vasorelaxation in HUV rings contracted with KCl 60 mM, while NCOE and BIS-NTHF have effects similar to the rings pre-contracted with 5 HT. Preincubation of GTN, BIS-NTHF and NTHF attenuated contractions induced by 5-HT in HUA rings. Additionally, GTN and BIS-NTHF also inhibited contraction stimulated by 5-HT in HUV. In contrast, preincubation of NTHF in HUV, and NCOE both in HUV as HUA led to lower inhibition when compared with the other nitrates. GTN, NTHF and BIS-NTHF inhibited the phasic and tonic components of the contraction induced by 5-HT in the absence of extracellular Ca2+. NCOE was more effective to inhibit the tonic contraction. Pre-incubation of 10 μM of ODQ, inhibitor of soluble cyclase guanylyl, attenuated significantly the vasodilator response to GTN, NTHF, NCOE and BIS NTHF was. Preincubation of 10 mM TEA, a blocker of potassium channels, decreased the relaxant response of the four nitrates in HUA, while do not alter the effect in HUV. In view of what has been exposed here, it can be concluded that GTN, NTHF, NCOE and BIS-NTHF cause vasorelaxation of HUCV rings, both in basal tone as contractions induced by 5-HT or KCl. The mechanism of nitrates action in these human vessels involves activation of sCG and channels for potassium; and inhibition of calcium entry, release of stocks of this ion by sarcoplasmic reticulum and ROCK activity. / Vasos umbilicais humano (HUCV), muitas vezes considerado lixo biológico, são bons modelos para avaliação de substâncias vasoativas. O efeito do trinitrato de gliceril (GTN) já foi caracterizado em vários vasos sanguíneos animais, mas em HUCV foi apenas relatado que este nitrato apresenta pouco efeito. O nitrato de tetra-hidrofurfurilo (NTHF) e o 13-nitrato-cis-9-octadecanoato de etila (NCOE) são doadores de óxido nítrico (NO), cujo efeito foi caracterizado em vasos animais. O 1,2-bis(tetrahidrofuran-2-il)etano-1,2-diildinitrato (BIS-NTHF) é um composto inédito (duas moléculas de NTHF) que não possui estudos farmacológicos. O objetivo deste estudo foi implantar e padronizar a técnica envolvendo HUCV, e caracterizar o efeito desses quatro nitratos orgânicos tanto em anéis de artéria (HUA) como veia (HUV) isoladas de cordão. A padronização da técnica mostrou que 3 g e 3h são, respectivamente, a tensão e tempo ideais para experimentos com os vasos umbilicais, além do fato de que estes apresentam uma queda espontânea tanto do tônus basal como do contrátil. O estudo com os nitratos mostrou que esses compostos relaxaram o tônus basal de HUCV. Todos os nitratos induziram vasorrelaxamento, em ambos os vasos umbilicais pré-contraídos com serotonina (5-HT), com efeitos máximos superiores a 90%, e com maior eficácia em relaxar HUA do que HUV. Nesta situação, GTN foi o nitrato mais potente em causar vasodilatação, BIS-NTHF apresentou um valor de potência intermediário, enquanto que NCOE e NTHF foram os menos potentes em relaxar HUV e HUA, respectivamente. Quando os anéis de HUA foram pré-contraídos com KCl 60 mM, houve uma atenuação da vasodilatação promovida pelos nitratos. GTN e NTHF também apresentaram o vasorrelaxamento diminuído nos anéis de HUV pré-contraídos com KCl 60 mM, enquanto NCOE e BIS-NTHF tiveram seus efeitos de forma semelhante aos anéis pré-contraídos com 5-HT. A pré-incubação de GTN, NTHF e BIS-NTHF atenuou as contrações induzidas por 5-HT, em anéis de HUA. Adicionalmente, GTN e BIS-NTHF também inibiram a contração estimulada por 5-HT em HUV. Em contrapartida, a pré-incubação de NTHF, em HUV, e de NCOE, tanto em HUV como em HUA, levaram à inibição menor, quando comparados aos outros nitratos. GTN, NTHF e BIS-NTHF inibiram o componente fásico e tônico da contração induzida por 5-HT, na ausência do Ca2+ extracelular. NCOE, por sua vez, foi mais eficaz em inibir a contração tônica. A pré-incubação de 10 μM de ODQ, inibidor da ciclase de guanilil solúvel, fez com que a resposta vasodilatadora de GTN, NTHF, NCOE e BIS-NTHF fosse atenuada de maneira significativa. A pré-incubação de 10 mM de TEA, um bloqueador de canais para potássio, em HUA diminuiu a resposta relaxante dos quatro nitratos, não alterando o efeito em HUV. Diante do exposto, pode-se concluir que os nitratos orgânicos GTN, NTHF, NCOE e BIS-NTHF causam vasorrelaxamento de anéis de HUCV, tanto no tônus basal quanto de contrações induzidas por 5-HT ou KCl. O mecanismo de ação dos nitratos nestes vasos humanos envolve ativação da sGC e de canais para potássio; e inibição da entrada de cálcio, liberação dos estoques deste íon do retículo sarcoplasmático e da atividade da ROCK.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T11:26:33Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T11:26:33Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2015-05-14T13:21:46Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1804420 bytes, checksum: 7f1229339fc39b87970bae7fb09a5054 (MD5) Previous issue date: 2009-11-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The major purposes for the production and use of biodiesels are environmental, social and economic benefits. However the production of 90 cubic meters of biodiesel generates about 10 cubic meters of glycerin, so partial or total replacement of diesel by biodiesel can because of glycerin generate a lot of problems. A great surplus (without market), could force the devaluation of its price, and glycerin factories losing competitiveness might be forced to close down. However the world is in a race to develop new processes and add new technologies for the rational use of bio-fuel co-products like glycerin. This study obtained "New Materials" by using glycerin with applicability to biology, diesel fuels, and bio-fuels with cetane improvers. We obtained five organic nitrates characterized as 2-nitrate-1,3-diethoxypropane (NDM); 2-nitrate-1,3- dimethoxypropane (NDE); 2-nitrate-1,3-dipropoxypropano (NDP); 2-nitrate-1.3-dibutoxypropano (NDB) and (+/-)-2,2-dimethyl-1,3- dioxolan-4-metilnitrato (nitrate solketal - NSKT). pharmacological evaluation showed that the nitrates of diesters have hypotensive activity on the cardiovascular system revealing NDB as the compound that showed greater potency and effectiveness against the vasorelaxant effect in the superior mesenteric artery isolated from rats in the order of 115.58 ± 5.59. The nitrate solketal ((+/-)-2,2-dimethyl-1,3-dioxolan-4-metilnitrato) (NSKT) was tested as a cetane improver for biodiesel so as to obtain a new low cetane bio-fuel. The addition of NSKT 7% to ethanol, formed a low cetane fuel capable of operating diesel engines. / O grande propósito para a produção e o uso do biodiesel são os benefícios ambientais, sociais e econômicos. Entretanto na produção de 90 m3 de biodiesel são gerados cerca de 10 m3 de glicerina, assim com a substituição parcial ou total do diesel pelo biodiesel a glicerina gerada no processo pode ser um grande problema econômico e ambiental. Uma grande produção de glicerina provoca a desvalorização do produto e conseqüentemente fábricas que produzem ou a usam como insumo podem perder competitividade até não ser mais viável o seu funcionamento. Todavia o mundo busca o desenvolvimento de novos processos e agregar novas tecnologias visando o aproveitamento racional da glicerina. Neste trabalho foram obtidos Novos Materiais pelo aproveitamento da glicerina do biodiesel com aplicabilidades biológicas na síntese de moléculas bioativas e em combustíveis ou biocombustíveis com os melhoradores de Cetano. Assim foram obtidos cinco nitratos orgânicos: 2-nitrato-1,3- dimetoxipropano (NDM); 2-nitrato-1,3-dietoxipropano (NDE); 2-nitrato- 1,3-dipropoxipropano (NDP) e o 2-nitrato-1,3-dibutoxipropano (NDB). A avaliação farmacológica mostrou que os nitratos dos diéteres possuem atividade hipotensora sobre o sistema cardiovascular sendo NDB o composto que apresentou maior potencia e eficácia frente ao efeito vasorelaxante na arteria mesentérica superior isolada de rato na ordem de 115,58 ± 5,59. O Nitrato de solketal ((+/-)-2,2-Dimetil-1,3-dioxolano-4- metilnitrato) (NSKT) foi testado como melhorador de cetano tanto para o biodiesel como para a obtenção de um novo biocombustível de baixo cetano. A adição de NSKT no teor de 7% ao etanol formou um combustível de baixo cetano capaz de funcionar um motor do ciclo diesel.