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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.
111

Síntese de 2-aril e 2,5-diarilfuranos funcionalizados: potenciais sondas fluorescentes / Synthesis of functionalized 2-aryl and 2,5-diarylfurans: potential fluorescent probes

Giancarlo di Vaccari Botteselle 14 September 2009 (has links)
A utilização de sondas fluorescentes para marcação ou detecção de biomoléculas de interesse em processos biológicos distintos, vem recebendo grande atenção em pesquisas biomédicas, de análises clínicas e biologia celular. Em geral, estas sondas fluorescentes são constituídas por moléculas orgânicas pequenas, as quais apresentam características fluorescentes e capacidade de conjugar-se com estas biomoléculas. Desta forma, esta dissertação descreve inicialmente a síntese de compostos 2-aril ou 2,5- diarilfuranos e tiofenos (3, 5, 7 e 9a-i), a partir de espécies orgânicas de telúrio (1, 4, 6 e 8) e sais de ariltrifluoroboratos de potássio (2a-i), via reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio [ver a figura no arquivo original]. Em seguida, descreve a síntese de um derivado 2,5-diarilfurano assimétrico, o 2-(3-aminofenil)-5-(4-metoxifenil)furano 11, o qual apresenta propriedades químicas e luminescentes adequadas para atuar como uma nova e promissora sonda fluorescente em processos de marcação ou detecção biológica. A síntese desta nova sonda, também chamada de 3-AFA (3-AnililFuranoAnisol), foi realizada a partir da reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio, entre o ácido (3-aminofenil) borônico 5e e o 2- (butiltelanil)-5-(4-metoxifenil)furano 10 em 65 % de rendimento. Esta nova sonda 3-AFA 11 foi conjugada com uma série de L-aminoácidos 12a-l, a partir de uma reação de acoplamento peptídico para formação dos respectivos produtos 13a-l em rendimentos satisfatórios. Estes produtos conjugados 13a-l, apresentam potencial para marcação fluorescente de enzimas proteolíticas de interesse [ver a figura no arquivo original]. Adicionalmente, foram caracterizadas propriedades fotofísicas importantes desta nova sonda 3-AFA 11, entre as quais seus espectros eletrônicos de absorção e emissão de fluorescência, que obtiveram valores de λex a 320 nm e λem a 400 nm, respectivamente. Por fim, foi testado o potencial de acúmulo intracelular da sonda 3-AFA 11 em sistemas celulares tais como: eritrócitos infectados com Plasmodium chabaudi e amastigotas de Leishmania L. amazonensis, sendo possível observar em todos os casos a marcação fluorescente dos respectivos parasitas. / The use of fluorescent probes for labeling or detection of biomolecules of interest in different biological processes, has received much attention in biomedical, clinical testing and cell biology research. In general, these fluorescent probes are composed of small organic molecules, which have fluorescent features and ability to combine with these biomolecules. Thus, this work initially describes the synthesis of 2-aryl or 2,5-diarylfurans and thiophenes (3, 5, 7 and 9a-i) from organic species of tellurium (1, 4, 6 and 8) and potassium organotrifluoroborate salts (2a-i) by palladium catalyzed Suzuki-Miyaura crosscoupling reaction [see the figure in the original file]. After describe the synthesis of a unsymmetrical 2,5-diarylfuran derivative, the 2-(3-aminophenyl)-5-(4-methoxyphenyl)furan 11, which presents chemical and luminescent properties appropriate to act as a promising new fluorescent probes in processes of marking or biological detection. The synthesis of this new probe, also called 3-AFA (3-AnilylFuranAnisole), was performed from palladium catalyzed Suzuki-Miyaura cross-coupling reaction, between (3- aminophenyl) boronic acid 5e and 2-(butyltellanyl)-5-(4-metoxyphenyl)furan 10 in 65 % yields. This new probe 3-AFA 11 was combined with a series of Lamino acids 12a-l from a peptidic coupling reaction to obtain their products 13a-l in satisfactory yield. These combined products 13a-l show a potential for fluorescent marking of proteolitic enzymes [see the figure in the original file]. Additionally, important photo physical properties of this new probe 3-AFA 11 were characterized. These include their electronic spectra of absorption and fluorescence emission, who obtained values of λex to 320 nm and λem to 400 nm, respectively. Finally, we tested the potential of probe 3-AFA 11 for intracellular accumulation in cellular systems such as: erythrocytes infected with Plasmodium chabaudi and amastigotes of Leishmania L. amazonensis, in all cases the fluorescent uptake cellular of their parasites can be observed.
112

Análise estereosseletiva do cloridrato de cis-tramadol e de suas impurezas em matéria-prima e formulação farmacêutica / Estereoselective analysis of cis-tramadol hydrocloride and its impurities in raw material and pharmaceutical formulation

Naíssa Prévide Bernardo 10 October 2008 (has links)
O cloridrato de tramadol, analgésico sintético de ação central, possui dois centros quirais: o isômero cis é ativo e o isômero trans é uma impureza de processo. Ambos os enantiômeros do cloridrato de cis-tramadol contribuem para o efeito analgésico, mas através de mecanismos diferentes, complementares e interativos farmacologicamente. Os dois isômeros do cis-tramadol apresentam efeitos terapêuticos, e a presença de impurezas, incluindo os isômeros trans - decorrentes do processo de síntese ou devido à decomposição - podem comprometer a qualidade do produto comercializado. Assim, este trabalho teve como objetivo desenvolver e validar metodologia estereosseletiva para análise do cloridrato de cis-tramadol e das possíveis impurezas quirais ou não na matéria-prima e formulações farmacêuticas. Para a separação e quantificação dos enantiômeros do cloridrato de cis-tramadol e das impurezas trans-tramadol, 1,2-olefina e 1,6-olefina, foi utilizada a coluna Chiralcel® OD-H, fase móvel constituída por hexano (60% e 100% de n-hexano, 1:1, v/v):isopropanol:dietilamina:ácido trifluoracético (99,5:0,5:0,3:0,1, v/v/v/v), na vazão de 0,7 mL min-1 e detecção em 274 nm. A coluna Chiralpak® AD fase móvel constituída por hexano (60% de n-hexano):etanol absoluto:dietilamina (95:5:0,1, v/v/v), na vazão de 1,0 mL min-1 e o comprimento de onda para detecção dos compostos foi de 228 nm foi utilizada para a separação e quantificação das impurezas O-desmetiltramadol, N-desmetiltramadol e tramadol N-óxido. Os métodos desenvolvidos foram devidamente validados através dos parâmetros seletividade, linearidade, precisão, exatidão, intervalo, limite de detecção e limite de quantificação. Os resultados obtidos na validação mostraram que os métodos são adequados para a determinação do cis-tramadol e de suas impurezas na matéria prima e na formulação farmacêutica. / Tramadol hydrochloride is a centrally acting analgesic with two chiral centers; the cis isomer is the active drug and the trans isomer is a process impurity. Both enantiomers of cis-tramadol hydrochloride contribute to the analgesic effect through different, but complementary and interactive pharmacological mechanisms. Although both isomers of cis-tramadol hydrochloride show therapeutic effects, the presence of impurities, originated from the synthesis process or due to degradation, can compromise the quality of the marketed product. The aim of this present work was the development and validation of a stereosselective methodology for the analysis of the drug cis-tramadol hydrochloride and the possible chiral or non-chiral impurities in raw materials and pharmaceutical formulations. The separation and quantitation of cis-tramadol enantiomers and the impurities trans-tramadol, 1,2-olefin and 1,6-olefin were carried out using a Chiralcel® OD-H column, mobile phase of hexane (60% and 100% of n-hexane, 1:1, v/v):2-propanol:diethylamine:trifluoroacetic acid (99,5:0,5:0,3:0,1, v/v/v/v) at a flow rate of 0,7 mL min-1 and detection at 274 nm. For the separation and quantitation of the impurities O-desmethyltramadol, N-desmethyltramadol and tramadol N-oxide, a Chiralpak® AD column was used with a mobile phase of hexane (60% of n-hexane):ethanol absolute: diethylamine (95:5:0,1, v/v/v) at a flow rate of 1,0 mL min-1 and detection at 228 nm. The methods were validated using the parameters selectivity, linearity, precision, accuracy, range, detection limit and quantitation limit. The results obtained show that the methods are suitable for the analysis of cis-tramadol and its impurities in raw material and pharmaceutical formulation.
113

Specifický cementový kompozit na bázi druhotných surovin s důrazem na trvanlivost / Specific cement composite based on secondary raw materials with emphasis on durability

Figala, Petr January 2018 (has links)
Nowadays the attention to the utilization of secondary raw materials as a component of building materials is being paid to in the Czech Republic and in the world. This thesis deals with possibilities of using secondary raw materials as partial cement substitutes in industrial floors. The aim of this thesis is to verify the influence of cement substitution amount with secondary raw materials and their fineness of grinding on the properties of the floor surface in time and on its structure. On the basis of the acquired knowledge, the influence of the pre-treatment of the secondary raw material on the properties of the floor ceiling with an emphasis on the economic aspect was assessed. After evaluating the results, some substitution of cement in the floor screed with secondary raw materials is beneficial. The significant influence of more intensive milling of the floor screeds base on the parameters of the final floor screed was not confirmed. It seems, that it is possible to achieve very good results even when using secondary raw materials with a lower percentage of fine particles. This brings together the economic benefits of lowering the cost of a lower dose of expensive cement by using cheaper secondary raw materials, because pre-treatment of such materials does not require the use of a large amount of energy.
114

Popílky jako surovinová základna budoucnosti / Ash – the raw material base for the future

Marko, Michal January 2018 (has links)
This master’s thesis responds to the worldwide problem concerning in the search of new material base for the future usage. Solid residues from high temperature or fluid coal combustion could be one of many alternatives to the raw materials. The study deals with the analysis of side energy products produced by power plant industry in the Czech Republic. Based on the fly ash chemical composition, possibilities of aluminium and even iron and titanium separation were proposed and then proved in the laboratory scale. Extracted components were separated selectively using apropriate methods. Then a couple of sintering reactions leading to improvement the leachability of selected elements from the fly ash matrix were carried out. Appropriate input material modification by high-temperature sintering reaction combined with extraction process in the sulfuric acid solution leads in dissolution up to 99 % of aluminium from the fluid and high-temperature fly ash.
115

Vývoj chemicky odolné stříkané směsi / Development of chemically resistant sprayed mixture

Hermann, Radek January 2019 (has links)
Production wastes for which a direct use in another production is found become secondary raw materials. There are several institutions in Czech Republic and in the world, which are currently dealing with the issue. This thesis deals with the issue of cementitious spray concrete mixtures and deals with the possibilities of using secondary raw materials and waste from production as partial replacement of binder and filler in these mixtures. The aim of this theses is to optimize the composition of additives in the recipe of the commercially produced pray mixture and to verify the influence of the degree of substitution of binder or filler by secondary raw materials on its physical-mechanical properties. The aim is to maintain or increase these properties while substituting the binder and filler as much as possible. After the evaluation of results, it is possible to say, by suitable optimization of the additives it is possible to achieve a significant improvement of the physical-mechanical properties of the mass and furthermore, from the results of this thesis follows, that by substitution of 100% fine filler in combination with substitution of 30% binder it is possible to maintain or increase the physical-mechanical properties after 28 days of curing and to significantly increase these properties after 90 days of curing. The results of this thesis are also related to the reduction of economic impact on production of the spray mixture, mainly due to the use of secondary raw materials.
116

Hodnocení ekonomické situace zvolené korporace a návrhy na její zlepšení / Assessment of the Economic Situation in Selected Corporation and Proposals for its Improvement

Polášková, Viktorie January 2019 (has links)
The diploma thesis is focused on the analysis of a chosen company that deals with waste treatment and how to use it further. The overall company´s situation is evaluated thanks to the chosen analytical methods which investigate inner and outer company´s surroundings. The suggestions and recommendations leading to the improvement of the observed situation are formulated on the basis of the analyses.
117

Efektivní návrh a provoz recyklační linky jako prvek komplexního odpadového řetězce / Effective proposal and operation of recycling line as an element in waste management

Dufka, Martin January 2019 (has links)
This master thesis deals with the current situation of waste management of material usable municipal waste with focus on various fractions of plastics. The theoretical part summarises the legislation of waste treatment, also contains an analysis of the current situation of waste management in the Czech Republic and comparison the situation in the European Union. In the next part of thesis are described basic fractions of plastics and their properties. There are mentioned the current problems with plastics processing and the risks of leakage to the environment. Furthermore, a complex chain of plastic waste reprocessing is described, since the inception of plastics waste to the manufacture of products made from recycled plastics. The most attention is paid to the discription of recycling plant, where the output material from sorting lines is reprocessed into a secondary material in the form of flakes or granules. Also this part is focused on the technology of recycling line and the individual devices are described. In the practical part of the thesis is created techno-economic model of recycling line with the aim of its use for balance calculations of recycling and also economic evaluation. As a part of the model was made a market research of secondary raw materials with a focus on price development. Subsequetly, sensitivity analyzes of selected parameters are applied to the model and the impact of scenarios on the economic results are evaluated.
118

Vývoj nového chemicky odolného nátěrového systému s obsahem druhotných surovin / Development of new chemically resistant coating system containing secondary raw materials

Stodolovská, Šárka January 2021 (has links)
New types of highly chemically resistant coating systems, primarily designed for concrete and metal substrates are designed and experimentally verified within the diploma thesis. Secondary raw materials, including solidified hazardous waste, are used as microfillers. The developed coating system is solved in two quality levels – PREMIUM and ECOLOGY. The level of PREMIUM is mainly designed for environments where extreme chemical stress is occurring. The polymer coating systém ECOLOGY can be used in environments where aggressive chemical media also act, however the ecological foot of the input raw materials is most important. The diploma thesis is dealing with current issues in the practice and it is the part of the research project.
119

Ověření různých druhů popílků pro výrobu umělého kameniva / Verification of different types of fly ash for production of artificial aggregate

Zahálka, Milan January 2014 (has links)
Diploma thesis gives an overview of artificial lightweight aggregates based on fly ash. Fly ash such as the residues of coal burning is currently one of the most used secondary raw materials for new building materials for research papers. The results shows that the secondary energy products are not just fully substitute the primary component, but in many cases improves the final properties of building products. Wide complex of fly ashes not only from domestic sources was tested and it`s main properties important for it`s further application was determined. Laboratory production of artificial aggregates based on fly ash made by sintering and also by cold bonding and following manufacture of artificial fly ash aggregates in technological conditions are also solved. The thesis is simultaneously concentrate on review of the suitability of fly ash aggregates in lightweight concrete.It was found that the highest quality fly ash for the production of sintered fly ash aggregate is fly ash and FBC ash is the best for the production of cold bonded aggregates. It was also verified that both types of aggregates are applicable to lightweight concrete class LC 20/22. The vast majority of manufactured aggregates is suitable for the production of lightweight concrete class LC 30/33. It was demonstrated that the sintered fly ash aggregates can be also used for high strength lightweight concrete class LC 50/55. Tests have also verified that all tested fly ashes and products produced from them meet the requirements of legislation on environment.
120

Vývoj speciálních ochranných hmot pro hygienicky čisté provozy / Development of special protective materials for hygienically clean areas

Seják, František January 2017 (has links)
The diploma thesis deals with the development of special protective materials for hygienically clean plants. The main aim of the thesis is to develop a special protective material on a polymer base usable for hygienically clean industrial plants in two quality levels (economy and premium). The first of the developed polymer protective materials is physiologically harmless (economy) – suitable for contact with eatables. Second, premium material is antibacterial, especially suitable as a floor coating in hospitals, kitchens, sanitary facilities, schools and kindergarten etc. A partial aim is the replacement currently used primary raw materials as fillers by suitable secondary raw material.

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