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Rezidua farmak v životním prostředí - interakce s vyššími rostlinami / Residua of Drugs in the Evironment - Interaction with Higher PlantsJirák, Jaroslav January 2016 (has links)
- 4 - Abstract The aim of this study was to carry out phytoextraction experiments using corn plants (Zea mays) and determine the phytoextraction efficiency for specific non-steroidal anti- inflammatory drugs and carbamazepine and their combinations. After 10 days of growth, a nutrient solution containing ibuprofene, naproxene, diclofenac and carbamazepine in concentrations ranging from 5 to 10 mg/L was added to hydrophonically cultivated plants. Nutrient solution samples were taken every 24 hours and the samples were then analysed using a HPLC/DAD system. At the end of the experiment, the experimental plants and roots were analysed for extractable residua using HPLC/DAD + FLD. The greatest phytoextraction efficiency was found for ibuprofene. The second and third most effective extraction was observed for naproxene and diclofenac, depending on the evaluation criteria. The lowest phytoextraction efficiency was observed for carbamazepine. With multi-component experiments, lower phytoextraction efficiency was found out for all substances with the exception of ibuprofene in combination with diclofenac and carbamazepine. The toxic impact of ibuprofene on plant transport mechanisms was also proven. The extractable residua analysis confirmed the ibuprofene's toxicity on plant transport mechanisms and also the...
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Estudo do comportamento térmico de asfaltenos de um petróleo brasileiro / Study of the thermal behavior of brazilian petroleum asphaltenesGonçalves, Maria Luisa Aleixo 27 February 2002 (has links)
A decomposição térmica dos asfaltenos é a principal responsável pela formação de coque no processamento de petróleos. O fenômeno não é claramente entendido, pelas dificuldades ainda existentes na caracterização de tais componentes pesados do óleo. Este trabalho apresenta informações sobre os produtos da decomposição térmica dos asfaltenos isolados de um petróleo da Bacia de Campos, maior bacia produtora de petróleo no Brasil. A abordagem envolveu: 1) estudos da decomposição térmica dos asfaltenos por termogravimetria (TG) em condições controladas; 2) caracterização dos produtos voláteis dessa decomposição por termogravimetria acoplada à cromatografia gasosa e espectrometria de massas (TG/DTA-CG-EM) e 3) caracterização dos produtos sólidos obtidos em diferentes temperaturas pela reação de oxidação catalisada pelo íon rutênio (RICO) que converte seletivamente alquil aromáticos em ácidos alcanóicos. A decomposição térmica dos asfaltenos foi estudada por termogravimetria. Os asfaltenos se decompõem drasticamente entre 320 e 650ºC produzindo 54% de produtos voláteis e 46% de coque. O material volátil liberado dos asfaltenos a 700°C foi analisado por TG/DTA acoplado a CG-EM. Foi identificada uma série de alcanos contendo de C3 a C10. Esse resultado causou grande surpresa, pois na análise da pirólise de diferentes asfaltenos são observados alcanos com maior número de átomos de carbono. Outro experimento foi realizado, agora em duas etapas: coleta do material volátil e injeção desta no sistema GC-EM. Desta vez foi possível identificar a série homóloga de alcanos de C11 até C33. Para o maior conhecimento da decomposição térmica dos asfaltenos, foram obtidos, em escala preparativa, produtos sólidos de decomposição térmica destes nas temperaturas de 320, 380, 400, 440, 480, 550 e 580°C. As análises realizadas nesses produtos - elementar, espectroscopia na região do infravermelho, ressonância magnética nuclear de carbono 13 no estado sólido - indicaram que quanto maior a temperatura de obtenção dos produtos sólidos, menor é o conteúdo de hidrogênio e carbono alifático. Os asfaltenos e os seus produtos de pirólise foram submetidos a reação de oxidação seletiva. Os ácidos gerados foram metilados para análise por CG-EM. Nos asfaltenos e nos produtos obtidos a 320, 380, 400 e 440°C foram identificados ésteres metílicos lineares que indicaram a presença de hidrocarbonetos alifáticos contendo de 5 a 25 átomos de carbono, ésteres metílicos de ácidos dicarboxílicos que indicaram a presença de pontes alquilicas entre os grupamentos aromáticos contendo de 3 a 15 átomos de carbono e alguns ésteres metílicos de ácidos benzenodicarboxílicos. Comparando-se o teor total desses ésteres metílicos presentes em cada produto de reação, foi verificado que a concentração dos ésteres metílicos lineares diminui lentamente a 320, 380, 400ºC, e drasticamente a partir de 400ºC. O mesmo ocorrendo com os ésteres dos ácidos dicarboxílicos e benzeno dicarboxílicos, em menor concentração que os ésteres metílicos lineares. / The thermal decomposition of asphaltenes is mainly responsible for the formation of coke in petroleum processing. The phenomena involved are not clearly understood, due to the difficulties in characterizing such heavy components. This research reports the application of thermal analysis techniques to study the thermal behavior of asphaltenes from Brazilian oil (Campos Basin). The approach involves: 1) studies of the thermal decomposition of asphaltenes under controlled conditions by thermogravimetry (TG); 2) characterization of volatile fractions by thermogravimetry and differential thermal analysis coupled with gas chromatography and mass spectrometry (TG/DT-GC-MS); 3) solid products from the thermal decomposition of asfaltenes where subjected to ruthenium (VIII) ion catalyzed oxidation reaction (RICO) that converts selectively and efficiently, alkyl aromatics to alkanoic acids. Thermogravimetry was used to study the asphaltenes thermal decomposition. The asphaltenes drastically decomposes from 320 to 650ºC to produce 54% of volatile products and 46% of coke. The volatile products of the asphaltenes at 700ºC were done by TG/DTA coupled to GC-MS. The volatile material was identified as a series of straight chain of normal alkyl ranging from C3 to C10. This result indicated limitations of the apparatus employed n-alkyl chains longer than these were expected. However, it worked well for lighter components. Another experiment, in which gaseous products from pyrolysis procedure were recovered by bubbling in CH2Cl2, accounted for the heavier components. The solution obtained this time can be analyzed by syringe injection in a CG-MS. The majority of the volatile material is constituted of straight chain alkanes ranging from C13 to C33. Knowing more about the thermal decomposition conversion of asphaltenes, the solid pyrolysis products of them were obtained in larger quantities at 320, 380, 400, 440, 480, 550 e 580ºC. They were characterized by elemental analysis and solid state 13C nuclear magnetic resonance. It was observed that at higher pyrolysis temperatures, lower the hydrogen and aliphatic carbon contents were obtained for the solid products. So, to improve knowledge on these systems, asphaltenes and their solid products from thermal decomposition were oxidized with ruthenium (VIII) ion. The acids formed were mixed with excess of ethereal diazomethane and submitted to GC-MS in order to identify the correspondent methyl esters. It was observed three homologous series: methyl esters of linear carboxylic acids ranging from C6 to C27, corresponding to chain alkyl length from C5 to C26 substituent on aromatic carbon; small amounts of dimethyl esters were also present in a homologous series, ranging from C5 to C17 indicating bridge polymethylenes between aromatics from C3 to C15 and benzene dicarboxilic acids from C10 to C12. The total content of methyl ester of each reaction products was compared. It was observed that the linear esters content decreased slowly at a 320, 380, 400°C and drastically up to 400ºC. The same occurred with the dimethyl aliphatic esters and dimethyl benzyl esters.
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Estudo do comportamento térmico de asfaltenos de um petróleo brasileiro / Study of the thermal behavior of brazilian petroleum asphaltenesMaria Luisa Aleixo Gonçalves 27 February 2002 (has links)
A decomposição térmica dos asfaltenos é a principal responsável pela formação de coque no processamento de petróleos. O fenômeno não é claramente entendido, pelas dificuldades ainda existentes na caracterização de tais componentes pesados do óleo. Este trabalho apresenta informações sobre os produtos da decomposição térmica dos asfaltenos isolados de um petróleo da Bacia de Campos, maior bacia produtora de petróleo no Brasil. A abordagem envolveu: 1) estudos da decomposição térmica dos asfaltenos por termogravimetria (TG) em condições controladas; 2) caracterização dos produtos voláteis dessa decomposição por termogravimetria acoplada à cromatografia gasosa e espectrometria de massas (TG/DTA-CG-EM) e 3) caracterização dos produtos sólidos obtidos em diferentes temperaturas pela reação de oxidação catalisada pelo íon rutênio (RICO) que converte seletivamente alquil aromáticos em ácidos alcanóicos. A decomposição térmica dos asfaltenos foi estudada por termogravimetria. Os asfaltenos se decompõem drasticamente entre 320 e 650ºC produzindo 54% de produtos voláteis e 46% de coque. O material volátil liberado dos asfaltenos a 700°C foi analisado por TG/DTA acoplado a CG-EM. Foi identificada uma série de alcanos contendo de C3 a C10. Esse resultado causou grande surpresa, pois na análise da pirólise de diferentes asfaltenos são observados alcanos com maior número de átomos de carbono. Outro experimento foi realizado, agora em duas etapas: coleta do material volátil e injeção desta no sistema GC-EM. Desta vez foi possível identificar a série homóloga de alcanos de C11 até C33. Para o maior conhecimento da decomposição térmica dos asfaltenos, foram obtidos, em escala preparativa, produtos sólidos de decomposição térmica destes nas temperaturas de 320, 380, 400, 440, 480, 550 e 580°C. As análises realizadas nesses produtos - elementar, espectroscopia na região do infravermelho, ressonância magnética nuclear de carbono 13 no estado sólido - indicaram que quanto maior a temperatura de obtenção dos produtos sólidos, menor é o conteúdo de hidrogênio e carbono alifático. Os asfaltenos e os seus produtos de pirólise foram submetidos a reação de oxidação seletiva. Os ácidos gerados foram metilados para análise por CG-EM. Nos asfaltenos e nos produtos obtidos a 320, 380, 400 e 440°C foram identificados ésteres metílicos lineares que indicaram a presença de hidrocarbonetos alifáticos contendo de 5 a 25 átomos de carbono, ésteres metílicos de ácidos dicarboxílicos que indicaram a presença de pontes alquilicas entre os grupamentos aromáticos contendo de 3 a 15 átomos de carbono e alguns ésteres metílicos de ácidos benzenodicarboxílicos. Comparando-se o teor total desses ésteres metílicos presentes em cada produto de reação, foi verificado que a concentração dos ésteres metílicos lineares diminui lentamente a 320, 380, 400ºC, e drasticamente a partir de 400ºC. O mesmo ocorrendo com os ésteres dos ácidos dicarboxílicos e benzeno dicarboxílicos, em menor concentração que os ésteres metílicos lineares. / The thermal decomposition of asphaltenes is mainly responsible for the formation of coke in petroleum processing. The phenomena involved are not clearly understood, due to the difficulties in characterizing such heavy components. This research reports the application of thermal analysis techniques to study the thermal behavior of asphaltenes from Brazilian oil (Campos Basin). The approach involves: 1) studies of the thermal decomposition of asphaltenes under controlled conditions by thermogravimetry (TG); 2) characterization of volatile fractions by thermogravimetry and differential thermal analysis coupled with gas chromatography and mass spectrometry (TG/DT-GC-MS); 3) solid products from the thermal decomposition of asfaltenes where subjected to ruthenium (VIII) ion catalyzed oxidation reaction (RICO) that converts selectively and efficiently, alkyl aromatics to alkanoic acids. Thermogravimetry was used to study the asphaltenes thermal decomposition. The asphaltenes drastically decomposes from 320 to 650ºC to produce 54% of volatile products and 46% of coke. The volatile products of the asphaltenes at 700ºC were done by TG/DTA coupled to GC-MS. The volatile material was identified as a series of straight chain of normal alkyl ranging from C3 to C10. This result indicated limitations of the apparatus employed n-alkyl chains longer than these were expected. However, it worked well for lighter components. Another experiment, in which gaseous products from pyrolysis procedure were recovered by bubbling in CH2Cl2, accounted for the heavier components. The solution obtained this time can be analyzed by syringe injection in a CG-MS. The majority of the volatile material is constituted of straight chain alkanes ranging from C13 to C33. Knowing more about the thermal decomposition conversion of asphaltenes, the solid pyrolysis products of them were obtained in larger quantities at 320, 380, 400, 440, 480, 550 e 580ºC. They were characterized by elemental analysis and solid state 13C nuclear magnetic resonance. It was observed that at higher pyrolysis temperatures, lower the hydrogen and aliphatic carbon contents were obtained for the solid products. So, to improve knowledge on these systems, asphaltenes and their solid products from thermal decomposition were oxidized with ruthenium (VIII) ion. The acids formed were mixed with excess of ethereal diazomethane and submitted to GC-MS in order to identify the correspondent methyl esters. It was observed three homologous series: methyl esters of linear carboxylic acids ranging from C6 to C27, corresponding to chain alkyl length from C5 to C26 substituent on aromatic carbon; small amounts of dimethyl esters were also present in a homologous series, ranging from C5 to C17 indicating bridge polymethylenes between aromatics from C3 to C15 and benzene dicarboxilic acids from C10 to C12. The total content of methyl ester of each reaction products was compared. It was observed that the linear esters content decreased slowly at a 320, 380, 400°C and drastically up to 400ºC. The same occurred with the dimethyl aliphatic esters and dimethyl benzyl esters.
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Posouzení kontaminace kalů z čistíren odpadních vod rezidui léčiv / Assessment of contamination of sewage sludge from wastewater treatment plant by drug residualsDvořáková, Petra January 2009 (has links)
The aim of diploma thesis was finding of the method for the determination of drug residua in sewage sludge from wastewater treatment plant. Selected sulfonamide and diaminopyrimidine antibiotics, which are used in human and veterinary medicine, were selected as target comopounds. They are discharged to the sewer systems together with the urine and faeces and enter the sewage treatment plant, where they are not completely removed. They can be found in treated waste water or in sewage sludge. They can enter to the environment, where they can induce negative effects on organisms in soil and water ecosystem. An optimized method was used for identification and determination of these antibiotics in real samples from the large-scale waste water treatment plant in Brno-Modřice and from the waste water treatment plant situated in the area of Veterinary and Pharmaceutical University Brno. Antibiotics were extracted from sewage sludge by ultrasonic and by pressure solvent extraction (PSE). Waste water and sewage sludge real samples were concentrated and cleaned by solid phase extraction (SPE). For determination these antibiotics high performance liquid chromatography with diode array detector (HPLC - DAD) was used.
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Sledování obsahu sulfonamidů v odpadních vodách z čistíren odpadních vod s různými technologiemi čištění / Monitoring of sulfonamides in wastewater from sewage treatment plants with different treatment technologiesChaloupková, Petra January 2015 (has links)
The aim of this thesis is to determine the presence of pharmaceuticals in wastewater from several wastewater treatment plants (WWTPs) with different number of equivalent persons and different treatment technologies. Five sulfonamides were chosen for a determination due to their wide usage in human and veterinary medicine practice. The specific compounds are sulfamerazine, sulfamethazine, sulfapyridine, sulfathiazole a sulfamethoxazole. For the determination of those sulfonamides, an UHPLC/DAD analytical method was chosen and optimized. There was also a need for optimization of SPE extraction method, especially a sample volume optimization. 250 mL was chosen as an ideal volume of wastewater sample for SPE. The optimized method was used for determination of sulfonamides in real wastewater samples from WWTP in Podivín, Pohořelice, Hustopeče, Valtice, Lednice and Mikulov. Average concentrations of pharmaceuticals in influent and effluent wastewater samples were in a range of 0,1 – 1 µg/l. The concentration of sulfonamides was mostly found higher in influent samples and lower in effluent samples. It can be said that a partial recovery of sulfonamides on WWTPs was observed.
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Automated construction of generalized additive neural networks for predictive data mining / Jan Valentine du ToitDu Toit, Jan Valentine January 2006 (has links)
In this thesis Generalized Additive Neural Networks (GANNs) are studied in the context of predictive Data Mining. A GANN is a novel neural network implementation of a Generalized Additive Model. Originally GANNs were constructed interactively by considering partial residual plots.
This methodology involves subjective human judgment, is time consuming, and can result in suboptimal
results. The newly developed automated construction algorithm solves these difficulties by
performing model selection based on an objective model selection criterion. Partial residual plots
are only utilized after the best model is found to gain insight into the relationships between inputs
and the target. Models are organized in a search tree with a greedy search procedure that identifies
good models in a relatively short time. The automated construction algorithm, implemented
in the powerful SAS® language, is nontrivial, effective, and comparable to other model selection
methodologies found in the literature. This implementation, which is called AutoGANN, has a
simple, intuitive, and user-friendly interface. The AutoGANN system is further extended with an
approximation to Bayesian Model Averaging. This technique accounts for uncertainty about the
variables that must be included in the model and uncertainty about the model structure. Model
averaging utilizes in-sample model selection criteria and creates a combined model with better predictive
ability than using any single model. In the field of Credit Scoring, the standard theory of
scorecard building is not tampered with, but a pre-processing step is introduced to arrive at a more
accurate scorecard that discriminates better between good and bad applicants. The pre-processing
step exploits GANN models to achieve significant reductions in marginal and cumulative bad rates.
The time it takes to develop a scorecard may be reduced by utilizing the automated construction
algorithm. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2006.
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Automated construction of generalized additive neural networks for predictive data mining / Jan Valentine du ToitDu Toit, Jan Valentine January 2006 (has links)
In this thesis Generalized Additive Neural Networks (GANNs) are studied in the context of predictive Data Mining. A GANN is a novel neural network implementation of a Generalized Additive Model. Originally GANNs were constructed interactively by considering partial residual plots.
This methodology involves subjective human judgment, is time consuming, and can result in suboptimal
results. The newly developed automated construction algorithm solves these difficulties by
performing model selection based on an objective model selection criterion. Partial residual plots
are only utilized after the best model is found to gain insight into the relationships between inputs
and the target. Models are organized in a search tree with a greedy search procedure that identifies
good models in a relatively short time. The automated construction algorithm, implemented
in the powerful SAS® language, is nontrivial, effective, and comparable to other model selection
methodologies found in the literature. This implementation, which is called AutoGANN, has a
simple, intuitive, and user-friendly interface. The AutoGANN system is further extended with an
approximation to Bayesian Model Averaging. This technique accounts for uncertainty about the
variables that must be included in the model and uncertainty about the model structure. Model
averaging utilizes in-sample model selection criteria and creates a combined model with better predictive
ability than using any single model. In the field of Credit Scoring, the standard theory of
scorecard building is not tampered with, but a pre-processing step is introduced to arrive at a more
accurate scorecard that discriminates better between good and bad applicants. The pre-processing
step exploits GANN models to achieve significant reductions in marginal and cumulative bad rates.
The time it takes to develop a scorecard may be reduced by utilizing the automated construction
algorithm. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2006.
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Využití kumulací pro biologické signály / Averaging of biological signalsNěmeček, Tomáš January 2014 (has links)
The main objectives of this thesis are to study theory of signal averaging, filtered residue method and methods of stretching/shrinking signal. It will also test the functionality of those methods. Thesis contains theoretical analysis, explanation of principles and testing of behaving of used methods.
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