O solo fornece suporte e atua como reservatório de água para as plantas, promovendo condições fundamentais ao crescimento de raízes e à dinâmica da água e nutrientes. O conhecimento de suas propriedades hidráulicas, como a curva retenção da água, é de grande importância na descrição e predição dos processos de transporte da água e solutos. O objetivo deste trabalho foi determinar a curva de retenção pelo método tradicional dos funis e câmaras de pressão de ar com placa porosa, pelo método de campo utilizando tensiômetros e pelo método da evaporação da água em amostra de solo no laboratório munida de tensiômetro. O solo utilizado para estudo foi classificado como Nitossolo Vermelho eutrófico de textura argilosa, e estava sendo cultivado com café há mais de 10 anos. A comparação entre as curvas obtidas pelos três métodos indicou que o método da evaporação diferiu estatisticamente do método do funil e câmara e foi estatisticamente idêntico ao método do tensiômetro a campo. Por sua facilidade de execução, baixo custo e rapidez na determinação da curva de retenção até a tensão de aproximadamente 100 kPa, o método da evaporação aqui apresentado é uma boa opção de utilização. Com relação ao método do tensiômetro no campo, embora mais realístico, é muito trabalhoso. / Soil provides support and acts as a water reservoir to plants, promoting essential conditions to root growth and to water and nutrient dynamics. The understanding of its hydraulic properties, like the water retention curve, is of great importance for the description and prediction of the processes of water and solute transport. The objective of this study was to determine soil water retention curve through the traditional method using porous plate funnel and pressure chamber, through the field method using tensiometers and through the water evaporation in soil sample with tensiometer in the laboratory. The studied soil was classified as clayey Rhodic Hapludox, which had been cultivated with coffee for more than 10 years. The comparison of curves obtained through the three methods indicated that the evaporation method was statistically different from the method using funnel and chamber, and statistically equal to the method of tensiometers at field. For its easy execution, low cost and quickness to determine soil water retention curve until the tension of about 100 kPa, the evaportation method presented here is a feasible option. As for the method of tensiometers at field, although it is more realistic, it is very laborious.

O solo fornece suporte e atua como reservatório de água para as plantas, promovendo condições fundamentais ao crescimento de raízes e à dinâmica da água e nutrientes. O conhecimento de suas propriedades hidráulicas, como a curva retenção da água, é de grande importância na descrição e predição dos processos de transporte da água e solutos. O objetivo deste trabalho foi determinar a curva de retenção pelo método tradicional dos funis e câmaras de pressão de ar com placa porosa, pelo método de campo utilizando tensiômetros e pelo método da evaporação da água em amostra de solo no laboratório munida de tensiômetro. O solo utilizado para estudo foi classificado como Nitossolo Vermelho eutrófico de textura argilosa, e estava sendo cultivado com café há mais de 10 anos. A comparação entre as curvas obtidas pelos três métodos indicou que o método da evaporação diferiu estatisticamente do método do funil e câmara e foi estatisticamente idêntico ao método do tensiômetro a campo. Por sua facilidade de execução, baixo custo e rapidez na determinação da curva de retenção até a tensão de aproximadamente 100 kPa, o método da evaporação aqui apresentado é uma boa opção de utilização. Com relação ao método do tensiômetro no campo, embora mais realístico, é muito trabalhoso. / Soil provides support and acts as a water reservoir to plants, promoting essential conditions to root growth and to water and nutrient dynamics. The understanding of its hydraulic properties, like the water retention curve, is of great importance for the description and prediction of the processes of water and solute transport. The objective of this study was to determine soil water retention curve through the traditional method using porous plate funnel and pressure chamber, through the field method using tensiometers and through the water evaporation in soil sample with tensiometer in the laboratory. The studied soil was classified as clayey Rhodic Hapludox, which had been cultivated with coffee for more than 10 years. The comparison of curves obtained through the three methods indicated that the evaporation method was statistically different from the method using funnel and chamber, and statistically equal to the method of tensiometers at field. For its easy execution, low cost and quickness to determine soil water retention curve until the tension of about 100 kPa, the evaportation method presented here is a feasible option. As for the method of tensiometers at field, although it is more realistic, it is very laborious.

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Submitted by ANA KARLA PEREIRA RODRIGUES (anakarla_@hotmail.com) on 2017-08-08T13:12:39Z No. of bitstreams: 1 arquivototal.pdf: 2266227 bytes, checksum: d3171f9e7352fd7ad3ac2fd448b412dc (MD5) / Made available in DSpace on 2017-08-08T13:12:39Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2266227 bytes, checksum: d3171f9e7352fd7ad3ac2fd448b412dc (MD5) Previous issue date: 2016-08-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this investigation we studied the polymer films formed of poly (vinyl alcohol) (PVA) and carboxymethylcellulose (CMC), both polymers readily available, and the synthetic first and second semi-synthetic. The films were prepared by evaporation of the solvent method and crosslinked with citric acid (CA) in order to improve their hydrophobicity characteristics. The crosslinked films and uncrosslinked were characterized via swelling measurements, the solubility and permeability to water vapors for testing the barrier properties of the films. In addition to these, antimicrobial activity assays were performed, scanning electron microscopy (SEM), thermal gravimetric analysis and spectroscopy in the infrared region. Infrared spectra suggested the formation of the blend by displacement of bands and showed that the crosslinking process occurred. Crosslinked films showed better results in relation to the water barrier properties (solubility, swelling and permeability) compared to films not lattices, results as they were, in fact, expected some time crosslinking rearranges the polymer chains in order to hinder the passage of water molecules and control the passage of smaller molecules. Thermal degradation analysis showed that the stability of the films was affected by the presence of citric acid crosslinking agent so that crosslinked films with higher concentrations of BC had greater stability of the thermal point of view. The SEM of the films showed a smooth and homogeneous surface without phase separation of blends and no porosities. The antimicrobial activity performed with strains of S. aureus, S. epidermidis, Pseudomonas aeruginosa, Candida albicans and C. topicalis showed that no film inhibition activity on the growth of microorganisms. Besides characterization was carried out applying the transdermal films for controlled drug release, which we evaluated the release kinetics of acetaminophen and drugs fluconazole crosslinked films 20 and 30% citric acid. The results of controlled drug release showed that the film exhibited different behaviors across the control release so that the blends presented model release of zero order, carboxymethylcellulose films to uncontrolled release and PVA films were able to maintain a concentration drug constant in the receiving environment after 12 hours of testing. / Nesse trabalho foram estudados os filmes poliméricos formados por poli (álcool vinílico) (PVA) e carboximetilcelulose (CMC), dois polímeros de fácil obtenção, sendo o primeiro sintético e o segundo semissintético. Os filmes foram preparados pelo método da evaporação do solvente e reticulados com ácido cítrico (AC), a fim de melhorar suas características de hidrofobicidade. Os filmes reticulados e não reticulados foram caracterizados via ensaios de intumescimento, solubilidade e permeabilidade aos vapores de água para testar as propriedades de barreira dos filmes. Além desses, foram realizados ensaios de atividade antimicrobiana, microscopia eletrônica de varredura (MEV), análise termogravimétrica e espectroscopia na região do infravermelho. Os espectros de infravermelho sugeriram formaçãoda blenda através de deslocamento de bandas e mostrou que o processo de reticulação ocorreu. Os filmes reticulados apresentaram melhores resultados em relação às propriedades de barreira à água (solubilidade, intumescimento e permeabilidade) quando comparados aos filmes não reticulados, resultados como eram, de fato, esperados, umas vez que a reticulação reorganiza as cadeias poliméricas de forma a dificultar a passagem de moléculas de água e controlar a passagem de moléculas menores. A análise de degradação térmica mostrou que a estabilidade dos filmes foi afetada pela presença do agente reticulante ácido cítrico, de forma que os filmes reticulados com maior concentração de AC apresentaram a maior estabilidade do ponto de vista térmico. O MEV dos filmes mostrou uma superfície lisa e homogênea, sem separação de fases das blendas e ausência de porosidades. A atividade antimicrobiana realizada com cepas de S. aureus, S. epidermides, Pseudomonas aeruginosa, Candida albicans e C. topicalis, mostrou que nenhum filme apresentou atividade de inibição sobre o crescimento dos microorganismos. Além da caracterização, foi realizada a aplicação dos filmes para sistemas transdérmicos de liberação controlada de fármacos, onde foi avaliada a cinética de liberação dos fármacos paracetamol e fluconazol em filmes reticulados com 20 e 30% de ácido cítrico. Os resultados da liberação controlada de fármacos mostraram que os filmes apresentaram diferentes comportamentos frente ao controle da liberação, de forma que as blendas apresentaram modelo de liberação de ordem zero, os filmes de carboximetilcelulose não controlaram a liberação e os filmes de PVA conseguiram manter uma concentração constante de fármaco no meio receptor após as 12 horas de ensaio.

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Supervisor: PharmDr. Ondřej Holas, Ph.D. Consultant: Mgr. Jana Kubačková Student: Lenka Voldřichová Title of thesis: Lipid based nanoparticles: drug delivery platform Lipic nanoparticles, as newly developed dosage forms, can overcome many drawbacks of conventional dosage forms. Their potential can be utilized in particular for prolonged, controlled and targeted release. They can also increase the bioavailability of drugs, especially those with poor solubility and also allow targeting, which causes increased accumulation of lipid nanoparticles in certain tissues compared to other tissues. nanoparticles suitable for drug encapsulation. The particles were prepared by the emulsion evaporation method. Their characterization was performed using a Zetasizer, which measured the particle size and the zeta potential. The properties of the formulations were evaluated in terms of nanoparticle size, polydispersity, zeta potential, and formulation properties. Differencial scanning calorimetry analysis was also performed on selected formulations. The selected final formulation was composed of 25 mg glycerol monostearate, 10 mg isopropyl myristate, 15 mg lecithin and Kolliphor P188 0,1% solution....

In recent years, there has been growing interests on II-VI semiconductor nanostructures, which are suitable for applications in electronics and optoelectronic devices such as solar cells, UV lasers, sensors, light emitting diodes and field emission displays. II-VI semiconductor nanostructures with different morphologies such as wires, belts, rods, tubes, needles, springs, tetrapods, plates, hierarchical structures and so on, have been widely grown by vapor transport methods. However the process conditions used for the growth of nanostructures still remains incompatible for device fabrication. The realization of practical nanoscale devices using nanostructured film depends mainly on the availability of low cost and lower processing temperatures to manufacture high purity nanostructures on a variety of substrates including glass and polymer. In this thesis work, studies have been made on the growth and characterization of II-VI semiconductor nanostructures prepared at room temperature, under high vacuum, without employing catalysts or templates. (i) ZnO nanostructured films with different morphology such as flowers, needles and shrubs were deposited at room temperature on glass and polymer substrates by plasma assisted reactive process. (ii) Zn/ZnO core/shell nanowires were grown on Si substrates under optimized oxygen partial pressure. Annealing of this core shell nanowire in high vacuum resulted in the formation of ZnO nanocanals. (iii) ZnS and ZnSe nano and microstructures were grown on Si substrates under high vacuum by thermal evaporation. The morphology, structural, optical properties and composition of these nano and microstructures were investigated by XRD, SEM, TEM, Raman, PL and XPS. The growth mechanism behind the formation of the different nanostructures has been explained on the basis of vapour-solid (VS) mechanism.