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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.
31

Avaliação do uso da cela de reação dinâmica em espectrometria de massas com plasma acoplado indutivamente (DRC-ICP-MS) para determinação de elementos químicos em sangue / Evaluation of the use of dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) for determination of elements in whole blood

Batista, Bruno Lemos 30 April 2009 (has links)
A espectrometria de massas com plasma acoplado indutivamente com simples quadrupolo (q-ICP-MS) e cela de reação dinâmica (DRC-ICP-MS) foi avaliada para determinação seqüencial de Al, As, Cd, Co, Cu, Cr, Mn, Mo, Pb, Pt, Sb, Se, Sn, Te, Tl, V e Zn em sangue. Para as análises, amostras de sangue (200 µL) foram diluídas 1:50 em uma solução contendo 0,01% v/v Triton® X-100 e 0,5% v/v de ácido nítrico. As calibrações foram realizadas com ajuste de matriz, utilizando sangue ovino. Como gás de reação utilizou-se a NH3. O uso do DRC foi fundamental para a determinação de Cr e V. A escolha da melhor vazão do gás e a otimização do parâmetro de rejeição (RPq) foram estudadas utilizando sangue base ovino ou uma solução de matriz sintética (SMS), de acordo com a concentração do analito no sangue base. Os limites de detecção (3s/coeficiente angular) para determinação de 27Al, 75As, 111Cd, 59Co, 63Cu, 55Mn, 98Mo, 208Pb, 195Pt, 123Sb, 82Se, 120Sn, 130Te, 205Tl e 66Zn em sangue por q-ICP-MS foram 0,223; 0,014; 0,003; 0,011; 0,304; 0,009; 0,009; 0,003; 0,001; 0,005; 0,264; 0,006; 0,010; 0,001; 0,834 µg L-1, respectivamente, e para determinação de 52Cr e 51V em sangue por DRC-ICP-MS utilizando o gás de reação amônia os limites de detecção foram de 0,007 e 0,006 µg L-1. Para a determinação de 27Al, 63Cu, 65Cu, 64Zn e 66Zn em sangue por q-ICP-MS através da calibração com ajuste de matriz com SMS os limites de detecção foram 0,083; 0,090; 0,055; 0,281; 0,306 µg L-1, respectivamente. A validação do método foi realizada por meio da análise de materiais de referência do INSP-Canadá, NYSDOH-EUA e Seronorm-Noruega. / The use of inductively coupled plasma mass spectrometry with quadrupole (q-ICP-MS) and dynamic reaction cell (DRC-ICP-MS) was evaluated for sequential determination of Al, As, Cd, Co, Cu, Cr, Mn, Mo, Pb, Pt, Sb, Se, Sn, Te, Tl, V and Zn in whole blood by q-ICP-MS or DRC-ICP-MS methods. Prior to analysis, sample (200 µL) were diluted 1:50 v/v in a solution containing 0.01% v/v Triton® X-100 and 0.5% v/v nitric acid. For all elements, except Cr and V, the instrument was operated in q-ICP-MS mode. The use of DRC was only mandatory for Cr and V. NH3 was evaluated as the reaction gas. Selection of best flow rate of reaction gas and optimization of the quadrupole dynamic bandpass rejection parameter (RPq) were carried out, using base whole blood or synthetic matrix solution (SMS), in according with element base blood concentration. Method detection limits (3s/slope) for 27Al, 75As, 111Cd, 59Co, 63Cu, 55Mn, 98Mo, 208Pb, 195Pt, 123Sb, 82Se, 120Sn, 130Te, 205Tl and 66Zn determination in whole blood by q-ICP-MS against matrix matching calibration (base blood) were 0.223; 0.014; 0.003; 0.011; 0.304; 0.009; 0.009; 0.003; 0.001; 0.005; 0.264; 0.006; 0.010; 0.001; 0.834 µg L-1, respectively, and for 52Cr and 51V determination in whole blood by DRC-ICP-MS the detection limits were 0.007 e 0.006 µg L-1. For 27Al, 63Cu, 65Cu, 64Zn and 66Zn determination by q-ICP-MS through matrix matching calibration with SMS the detection limits were 0.083; 0.090; 0.055; 0.281; 0.306 µg L-1, respectively. Method validation was accomplished by the analysis of reference materials from INSP-Canada, NYSDOH-USA, Seronorm-Norway.
32

La resucitación de las voces : Un estudio narratológico de Mazurca para dos muertos de Camilo José Cela

Forsberg, Kirsi January 2009 (has links)
<p>Para estudiar cómo se presenta la relación entre Ficción e Historia o entre Ficción y Memoria del pasado reciente en la novela contemporánea de lengua castellana, se ha optado por Mazurca para dos muertos de Camilo José Cela, que toca la época de la Guerra Civil española. El objetivo es hacer un análisis sobre las voces narrativas; para esto se ha usado un método narratológico. Se ha partido de la premisa de que la novela en cuestión es una construcción de una polifonía de voces que abarca el dialogismo. Se mantiene la hipótesis de que la diversidad de voces y el dialogismo se hallan inmersos en los testimonios directos de los acontecimientos acaecidos durante la Guerra Civil, de los que, sin embargo, se obtiene una perspectiva limitada: cada una de las voces se distingue, pero existe una relación o conexión temática entre ellas. La historia se enfoca desde una visión y un punto de vista de un primer narrador desde donde se aborda el conjunto de la historia; este utiliza numerosos modalizadores para orientar a los lectores en su dirección de opinión. Así elabora el discurso a partir de la información recabada desde las voces narrativas que completan el punto de vista del primer narrador desde diferentes perspectivas. Por eso se sostiene, en las conclusiones, que el diálogo y la polifonía son un modo de organización estructural, pero que, también, sirven como herramientas con las que se enfoca la historia desde el ángulo subjetivo de un narrador. Se subraya, además, lo magistral logrado en la trancripción de una realidad oral y la representación verosímil de la historia.</p>
33

La resucitación de las voces : Un estudio narratológico de Mazurca para dos muertos de Camilo José Cela

Forsberg, Kirsi January 2009 (has links)
Para estudiar cómo se presenta la relación entre Ficción e Historia o entre Ficción y Memoria del pasado reciente en la novela contemporánea de lengua castellana, se ha optado por Mazurca para dos muertos de Camilo José Cela, que toca la época de la Guerra Civil española. El objetivo es hacer un análisis sobre las voces narrativas; para esto se ha usado un método narratológico. Se ha partido de la premisa de que la novela en cuestión es una construcción de una polifonía de voces que abarca el dialogismo. Se mantiene la hipótesis de que la diversidad de voces y el dialogismo se hallan inmersos en los testimonios directos de los acontecimientos acaecidos durante la Guerra Civil, de los que, sin embargo, se obtiene una perspectiva limitada: cada una de las voces se distingue, pero existe una relación o conexión temática entre ellas. La historia se enfoca desde una visión y un punto de vista de un primer narrador desde donde se aborda el conjunto de la historia; este utiliza numerosos modalizadores para orientar a los lectores en su dirección de opinión. Así elabora el discurso a partir de la información recabada desde las voces narrativas que completan el punto de vista del primer narrador desde diferentes perspectivas. Por eso se sostiene, en las conclusiones, que el diálogo y la polifonía son un modo de organización estructural, pero que, también, sirven como herramientas con las que se enfoca la historia desde el ángulo subjetivo de un narrador. Se subraya, además, lo magistral logrado en la trancripción de una realidad oral y la representación verosímil de la historia.
34

Avaliação do uso da cela de reação dinâmica em espectrometria de massas com plasma acoplado indutivamente (DRC-ICP-MS) para determinação de elementos químicos em sangue / Evaluation of the use of dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) for determination of elements in whole blood

Bruno Lemos Batista 30 April 2009 (has links)
A espectrometria de massas com plasma acoplado indutivamente com simples quadrupolo (q-ICP-MS) e cela de reação dinâmica (DRC-ICP-MS) foi avaliada para determinação seqüencial de Al, As, Cd, Co, Cu, Cr, Mn, Mo, Pb, Pt, Sb, Se, Sn, Te, Tl, V e Zn em sangue. Para as análises, amostras de sangue (200 µL) foram diluídas 1:50 em uma solução contendo 0,01% v/v Triton® X-100 e 0,5% v/v de ácido nítrico. As calibrações foram realizadas com ajuste de matriz, utilizando sangue ovino. Como gás de reação utilizou-se a NH3. O uso do DRC foi fundamental para a determinação de Cr e V. A escolha da melhor vazão do gás e a otimização do parâmetro de rejeição (RPq) foram estudadas utilizando sangue base ovino ou uma solução de matriz sintética (SMS), de acordo com a concentração do analito no sangue base. Os limites de detecção (3s/coeficiente angular) para determinação de 27Al, 75As, 111Cd, 59Co, 63Cu, 55Mn, 98Mo, 208Pb, 195Pt, 123Sb, 82Se, 120Sn, 130Te, 205Tl e 66Zn em sangue por q-ICP-MS foram 0,223; 0,014; 0,003; 0,011; 0,304; 0,009; 0,009; 0,003; 0,001; 0,005; 0,264; 0,006; 0,010; 0,001; 0,834 µg L-1, respectivamente, e para determinação de 52Cr e 51V em sangue por DRC-ICP-MS utilizando o gás de reação amônia os limites de detecção foram de 0,007 e 0,006 µg L-1. Para a determinação de 27Al, 63Cu, 65Cu, 64Zn e 66Zn em sangue por q-ICP-MS através da calibração com ajuste de matriz com SMS os limites de detecção foram 0,083; 0,090; 0,055; 0,281; 0,306 µg L-1, respectivamente. A validação do método foi realizada por meio da análise de materiais de referência do INSP-Canadá, NYSDOH-EUA e Seronorm-Noruega. / The use of inductively coupled plasma mass spectrometry with quadrupole (q-ICP-MS) and dynamic reaction cell (DRC-ICP-MS) was evaluated for sequential determination of Al, As, Cd, Co, Cu, Cr, Mn, Mo, Pb, Pt, Sb, Se, Sn, Te, Tl, V and Zn in whole blood by q-ICP-MS or DRC-ICP-MS methods. Prior to analysis, sample (200 µL) were diluted 1:50 v/v in a solution containing 0.01% v/v Triton® X-100 and 0.5% v/v nitric acid. For all elements, except Cr and V, the instrument was operated in q-ICP-MS mode. The use of DRC was only mandatory for Cr and V. NH3 was evaluated as the reaction gas. Selection of best flow rate of reaction gas and optimization of the quadrupole dynamic bandpass rejection parameter (RPq) were carried out, using base whole blood or synthetic matrix solution (SMS), in according with element base blood concentration. Method detection limits (3s/slope) for 27Al, 75As, 111Cd, 59Co, 63Cu, 55Mn, 98Mo, 208Pb, 195Pt, 123Sb, 82Se, 120Sn, 130Te, 205Tl and 66Zn determination in whole blood by q-ICP-MS against matrix matching calibration (base blood) were 0.223; 0.014; 0.003; 0.011; 0.304; 0.009; 0.009; 0.003; 0.001; 0.005; 0.264; 0.006; 0.010; 0.001; 0.834 µg L-1, respectively, and for 52Cr and 51V determination in whole blood by DRC-ICP-MS the detection limits were 0.007 e 0.006 µg L-1. For 27Al, 63Cu, 65Cu, 64Zn and 66Zn determination by q-ICP-MS through matrix matching calibration with SMS the detection limits were 0.083; 0.090; 0.055; 0.281; 0.306 µg L-1, respectively. Method validation was accomplished by the analysis of reference materials from INSP-Canada, NYSDOH-USA, Seronorm-Norway.
35

Desenvolvimento de procedimentos analíticos empregando multicomutação em sistemas de análises em fluxo para determinação fotométrica de vanádio em águas e estanho em alimentos / Development of analytical procedures employing multicommutation flow analysis systems for the photometric determination of vanadium in water and tin in foods

Tuanne dos Reis Dias 06 November 2014 (has links)
Esta tese tem como foco o desenvolvimento de procedimentos analíticos automáticos, visando as determinações fotométricas de vanádio e de estanho em águas e em alimentos empregando o processo de multicomutação em fluxo. Um microcontrolador da família PIC e um programa escrito em linguagem Visual Basic 6.0 foram empregados para controle dos dispositivos e aquisição de dados. A unidade de detecção foi construída empregando LED de alto brilho e celas de fluxo com longo caminho óptico (50-200 mm) para ganho em sensibilidade. O módulo de análises, empregando bombas solenoide como propulsores de fluido e o fotômetro foram integrados, formando uma unidade compacta. A determinação de vanádio em águas, mineral e de rio, foi baseada na redução do V(V) à V(IV) com ácido ascórbico e posterior complexação com Eriocromo Cianina R (ECR). Empregando uma cela de 150 mm, o sistema apresentou resposta linear de 0,02 a 1,00 mg L-1, limite de detecção estimado em 13 ?g L-1, coeficiente de variação de 0,87% (n=10) e frequência analítica de 47 determinações por hora. Recuperações entre 89 e 109% foram obtidas para adição de V(V) nas amostras de águas. O procedimento para a determinação de estanho em alimentos foi desenvolvido empregando bomba de multi-seringa como unidade de propulsão de fluidos, cela de fluxo com caminho óptico de 200 mm e parada de fluxo de 50 s. Baseado na reação do Sn(IV) com o violeta de pirocatecol (PCV) na presença de surfactantes, o sistema apresentou resposta linear de 0,10 a 1,25 mg L-1, limite de detecção estimado em 0,04 mg L-1, coeficiente de variação de 1,30% (n=10) e frequência analítica de 49 determinações por hora. Recuperações entre 95 e 115% foram obtidas com a adição de Sn(IV) às amostras de alimentos. / Automatic analytical procedures for photometric determinations of vanadium in water and tin in foods were developed using the multicommutation flow analysis process. A microcontroller of the PIC family and a software written in Visual Basic 6.0 language were used for devices control and data acquisition. Detection unit was designed to use high brightness LED and long optical pathlength flow cells (50-200 mm) to improve sensitivity. The flow analysis module using solenoid mini-pumps as fluid propelling devices and the photometer were integrated in order to form a compact unit. The determination of vanadium in mineral and river waters was based on the reduction of V(V) to V(IV) with ascorbic acid and subsequent complexation with Eriochrome Cyanine R (ECR). Employing flow cell of 150 mm, the system presented linear response between 0.02 and 1.00 mg L-1, detection limit of 13 ?g L-1, variation coefficient of 0.87% (n=10) and sampling throughput of 47 determinations per hour. Recoveries between 89 and 109% were attained for vanadium spiked to mineral and river water. The procedure for determination of tin in foods was development employing a multi-syringe pump as fluid propelling device, a flow cell with optical pathlength of 200 mm and stop flow of 50 s. The procedure was based on the reaction of Sn(IV) with pyrocatechol violet (PCV) in the presence of surfactants, presented linear response between 0.10 and 1.25 mg L-1, detection limit of 0.04 mg L-1, variation coefficient of 1.30% (n=10) and sampling throughput of 49 determination per hour. Recoveries between 95 and 115% were attained for tin spiked samples
36

Konstrukce a porovnání elektrochemických cel pro stanovení olova technikou generování těkavých sloučenin / Construction and comparison of electrochemical cells for lead determination by volatile compounds generation technique

Hillmich, Ondřej January 2017 (has links)
This diploma thesis is focused on the construction of the electrochemical cells for the lead determination using electrochemical generation of volatile compounds connected with the atomic absorption spectrometry as a detection technique. Three different electrochemical cells were constructed: membrane electrochemical cell (MEC), non-membrane electrochemical cell 1 (BEC1) and non-membrane electrochemical cell 2 (BEC2). Experimental conditions were optimized in continuous flow mode with cells BEC1 and BEC2. The optimization include flow rate of carrier gas, composition and concentration of the electrolytic solution, atomization temperature, generation current and voltage applied to the electrode material. A 1.0 mm diameter cadmium wire was used as cathode material and the anode material was composed of platinum wire of 0.5 mm in diameter. Under the optimal experimental conditions, the calibration was constructed and basic characteristics of proposed method were determined for the BEC1 and BEC2 cells: limit of detection, limit of quantification, repeatability, sensitivity, linear dynamic range and correlation factor of linear dynamic range. The cell MEC was found to be unsuitable for the lead determination by the electrochemical generation of volatile compounds. Using the BEC1 cell, the experimental...
37

Příprava a charakterizace extraktu z bezových květů / Preparation and characterization of extract from elderberry flowers

Lukšová, Leona January 2019 (has links)
This diploma thesis deals with the determination of conditions for the preparation of elderberry extract so that the prepared extract retains as many biologically active substances as possible and the way of preserving this extract. Furthermore, the work deals with the transmittance of already specific phenolic acids, namely chlorogenic acid, coffee and ferulic skin, through the Franc diffusion cells. In the theoretical part of the thesis there is a taxonomic classification, description and use of elderberry. Furthermore, significant active substances, in particular phenolic acids, are mentioned. beneficial effects on the skin. The anatomy of the skin and the problem of the penetration of phenolic acids through the skin are described in detail. Finally, a description of high performance liquid chromatography is provided. The experimental part is devoted to verification of optimal conditions for preparation of extract. The best option is to extract the flowers with water at 100 ° C for 10 minutes in a ratio of 1 part by weight of dry flowers and 10 parts by volume boiling water. The ratio of flowers and stems to the phenolic acid content of the extract was also investigated. In the flower extract and its thickened version, the skin permeability was examined by transdermal absorption. The aim of this experiment was to find out if and how much the above mentioned phenolic acids go through the skin. As skin membrane, pork skin from the auricle was used. All determinations of the above phenolic acids in all samples were carried out by liquid chromatography.
38

Komplexní model turbulence pro různé velikosti cel / Complex turbulent model for various cells dimensions

Maluš, Miroslav January 2021 (has links)
This diploma thesis is about creating a program to model turbulent cells of different sizes on the chosen transmission path. The initial part of the work is devoted to the formation of atmospheric turbulence and the mathematical description of the extent of turbulence and its effect on optical waves. The methods of the turbulence generation and their physical description of formation are described below. The practical part is devoted to the created program in the MATLAB.
39

Měření relativní variance optické intenzity / Measurement of relative variance of optical intensity

Vaníček, Jakub January 2011 (has links)
The intention of this master‘s thesis is the measurment of relative variance of optical intensity. In the first place, I have been studied Kolmogorov cascade theory of turbulence and relative variance of optical intensity . In addition, I have been deal with turbulent cells, Gaussian beam, Top Hat beam and influence of the atmospheric turbulences on the intensity profile of the laser beam. Lastly I have been measured determine influence of the atmospheric turbulences on the intensity profile of the laser beam and I have been calculated relative variance of optical intensity. I have suggested the optimum beam profile in the turbulent atmosphere from acquired data.
40

Experimentální studium a teoretické modelování transdermálního transportu aktivních látek z gelových matric / Experimental study and modelling of the transdermal penetration of active species from gels

Palanová, Veronika January 2016 (has links)
This diploma thesis deals with design and experimental study of transdermal transport of pharmaceutically active agents from gel matrices, which contain humic substance in its structure. A model absorption membrane was represented by the skin of pig´s earlobes. The study of the release of active substances and Lignohumte was performed due to the vertical diffusion cells. The amount of released humic substance was characterized by UV-VIS method and the amount of released active agent from gel matrix was determined by HPLC-DAD. The most interesting finding of this diploma thesis was that Lignohumate enhances transdermal transport of active agents and supports their release from gel samples to the particular environment.

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