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The effects of repeated bouts of prolonged cycling and carbohydrate supplementation on immunoendocrine responses in manLi, Tzai-Li January 2004 (has links)
Prolonged strenuous exercise affects the circulating numbers and functions of immune cells. These effects are thought to be largely mediated by the actions of elevated circulating stress hormones and alterations in regulatory cytokines. Although the effects of a single acute bout of exercise on immune system function are quite well established, it is still not clear how time of day and repeated bouts of prolonged exercise on the same day influence immune function. It is of particular interest to understand the effects of nutritional supplementation on immunoendocrine responses. Therefore, the aims of the studies described in this thesis were to determine the effects of two bouts of prolonged cycling and carbohydrate supplementation on immunoendocrine responses. The saliva collection study showed that the use of a swab for collecting saliva is not an ideal method because it affects the results of saliva composition (Chapter 4). The comparison of the effects of exercise at different times of day on immunoendocrine responses showed that a single bout of prolonged exercise performed in the afternoon induces a larger perturbation in the redistribution of leukocytes into the circulation than an identical bout of morning exercise, which maybe due to higher hypothalamic-pituitaryadrenal (HP A) activation and. circadian rhythms. However, in terms of oral mucosal immunity, performing prolonged cycling at different times of day does not differently affect the salivary responses. The second compared with the first of two bouts of prolonged exercise on the same day induces a greater HP A activation, a larger leukocyte trafficking into the circulation, a decreased neutrophil degranulation response to lipopolysaccharide (LPS) on per cell basis and a lower saliva flow rate, but does not increase plasma interleukin-6 (IL-6), or change saliva immunoglobulin A (slgA) secretion rate (Chapter 5). Furthermore, carbohydrate (CHO) ingestion during any period of two bouts of prolonged exercise shows limited beneficial effect in blunting these higher responses in the second exercise bout compared with the first identical exercise bout on the same day (Chapter 6, 7 and 8). The determination of the effects of CHO ingestion on exercise-induced immunoendocrine responses showed that when two bouts of exercise are performed on the same day, the greater benefit in terms of circulating immunoendocrine responses is obtained by feeding CHO at the earliest opportunity (Chapter 6, 7 and 8). A 3-h interval is insufficient for recovery of leukocyte mobilisation and neutrophil function from the impact of previous exercise whether subjects consumed placebo or CHO during exercise or recovery (Chapter 5, 6, 7 and 8). However, an 18-h interval is sufficient for full recovery of all immunoendocrine variables that were measured in this thesis from the impact of two bouts of prolonged exercise (Chapter 8).
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Characterization of Perphenazine and Scopolamine Aerosols Generated Using the Capillary Aerosol GeneratorLi, Xihao 01 January 2006 (has links)
The characterization of perphenazine and scopolamine aerosols generated using the capillary aerosol generator (CAG) was reported. Variables including steady state power, the formulation vehicle, the drug concentration and the formulation flow rate were studied for their effects on the chemical stability and particle size of these drug aerosols.Stability-indicating HPLC and LC-MS assays were developed and validated for perphenazine and scopolamine, respectively. The chemical stability of each compound was investigated under a variety of stress conditions and the structure of degradation products was proposed.Perphenazine aerosols were generated from propylene glycol (PG) formulations with concentrations of 9, 48 and 90mM at formulation flow rates of 2.5 and 5.0µL/s at a series of steady state powers. At higher aerosolization powers, the low concentration formulation (9mM) degraded with dehalogenation being the major pathway. The size of perphenazine aerosols was between 0.4 to 0.6µm. Changing the solute concentration produced only small changes (~0.2µm) in perphenazine aerosol particle size. The formulation flow rate did not significantly affect the aerosol size.Scopolamine degraded significantly when aerosolized in PG formulations. It was possible to generate chemically stable scopolamine aerosols from ethanol formulations. Significant amounts of degradation products were formed only at or above 4.6W at 5.0µL/s. Hydrolysis and dehydration appeared to be the major degradation pathways at higher powers and low formulation flow rate. The MMAD of scopolamine aerosols was between 0.5 and 2.0µm from 8, 20 and 40mM formulations at 5.0 and 10.0µL/s. The size of scopolamine aerosols increased as a function of increasing the solute concentration. Increasing the formulation flow rate increased the linear velocity of the spray, thus the Reynolds number was increased and smaller particles were generated.
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FILTER PERFORMANCE UNDER SIMULATED REAL-WORLD CONDITIONSWang, Qiang 01 January 2016 (has links)
Evaluating the performance of filter media for filtration applications is essential to assure design engineers and users that filter device will deliver promised performance for specific applications under the environmental stress. The study of particle loading characteristics of filter media in the laboratory setting is typically performed under the steady flow conditions, i.e., at the constant particle concentration and flow rate. In reality, filtration products are operated under the situations that the flow rate and mass concentration of particles are varied in time. The success of translating the laboratory data to estimate the performance of filter media in the fields is thus limited. It is necessary to investigate the performance of filter media under the real-world conditions, i.e., unsteady flow rate and mass concentration to bridge the gap.
The overall goals of this research are (1) to study the performance of filter medium under unsteady conditions (i.e., the performance of respirator filter media under simulated breathing conditions); and (2) to investigate the issue of non-uniform particle deposition on HVAC filter panels. A new experimental setup was developed to accomplish the former goal. Numerical modeling tool, Computational fluid dynamics (CFD), was applied to achieve the latter objective……
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Training, taper and recovery strategies for effective competition performance in judoPapacosta-Kokkinou, Elena January 2015 (has links)
Post-exercise carbohydrate-protein consumption and tapering periods during training periodisation have been proposed as effective recovery strategies in several sports; however, limited attention has been given to judo. Apart from training and recovery, effective competition performance can also be influenced by several stimuli on the competition day, which may be manifested as distinct endocrine responses. The main objective of this thesis was to influence effective competition performance in judo, through examining strategies that can aid recovery from intense exercise/training and examining endocrine responses to competition. Three experimental studies on recovery were completed (chapters 3-5) followed by an observational study on a judo competition day (chapter 6) in elite, national level, male judo athletes. Studies 1 and 2 examined the effects 1000 ml of post-exercise chocolate milk (CM) consumption compared with water (W) following an intense judo training session (chapter 3) and five days of intense judo training with concomitant weight loss (chapter 4) on the recovery of salivary cortisol (sC), salivary testosterone (sT), salivary testosterone:cortisol (sT/C) ratio, salivary secretory IgA (SIgA) absolute concentrations and secretion rate, muscle soreness, mood state and judo-related performance. Study 1 (n=10) did not show any beneficial effects of acute CM consumption on aspects of recovery of any of the measured variables, except for a lower perception of soreness (p<0.05) and a tendency for better push-up performance (p=0.09). Study 2 (n=12) showed that post-exercise CM consumption resulted in significantly lower sC levels, a tendency for higher sT/C ratio (p=0.07), better judo-related performance, lower muscle soreness and reduced mood disturbance (p<0.05) with W. In addition, post-exercise consumption of CM resulted in a 1.1% decrease in body weight, indicating that CM is an effective recovery beverage during periods of intense judo training without affecting intentional weight loss. Study 3 (n=11) examined the effects of a 2-week exponential taper following 2 weeks of intense judo training on recovery of the aforementioned variables. Within 12 days of tapering there were evidence of enhanced performance, lower sC, higher sT and higher sT/C ratio, higher SIgA secretion rate, lower muscle soreness and reduced mood disturbance, indicating that a tapering period of ~10 days is an effective recovery strategy for optimising judo performance. Study 4 observed the responses of sC, sT, SIgA absolute concentrations and SIgA secretion rate and self-measured anxiety state in the winners (n=12) and losers (n=11) of a judo competition. Winners presented significantly higher morning sC levels and higher cognitive anxiety in anticipation of the competition, as well as a tendency for higher SIgA secretion rate (p=0.07) and significantly higher saliva flow rate mid-competition. These findings indicate that winners experienced higher arousal levels and that anticipatory sC might have some predictive value for winning performance in judo. This thesis concludes that nutrition and tapering are both important aspects of effective recovery; CM can be an effective nutritional recovery aid during periods of intense judo training and tapering for 7-12 days can optimise judo performance and can be implemented prior to competitions. In addition, elevated sC levels in anticipation of a judo competition and higher levels of arousal could have some predictive value for winning performance in judo. Further research could focus on strategies to increase levels of arousal in anticipation of competition.
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Xerostomia em pacientes idosos: relação com o fluxo salivar, proteínas totais, capacidade tampão, pH e medicação em uso / Xerostomia in the elderly: relation to salivary flow rate, proteins, buffer capacity, pH and drugsTerci, Adriana Oliveira 30 November 2007 (has links)
O objetivo deste trabalho foi o de investigar as relações entre a queixa de boca seca, em uma população de idosos em bom estado geral, com o fluxo salivar não estimulado, a concentração de proteínas salivares, o pH e a capacidade tampão da saliva, além de considerar as medicações de uso diário consumidas por esses indivíduos. Foram selecionados de forma seqüencial e aleatória 85 pacientes, 13 homens e 72 mulheres, entre os 60 e 82 anos de idade, com média de 68,5 anos. Vinte e um pacientes, todos do sexo feminino, apresentaram queixa de boca seca, quando questionados. Sessenta e sete pacientes utilizavam algum tipo de medicação (79% da casuística). Dezoito indivíduos não consumiam medicamentos, 15 entre os não queixosos de boca seca e apenas três entre os que apresentaram queixa de boca seca. Foram colhidas amostras de saliva de todos os indivíduos, segundo técnica de expectoração não estimulada para recipiente mantido sob refrigeração, durante 15 minutos. Foram feitas, imediatamente após a coleta, o cálculo do fluxo salivar em mililitros por minuto, as medidas do pH, da capacidade tampão e reservados 2ml de saliva em recipiente refrigerado para os procedimentos da pesquisa da concentração proteica salivar. Ainda após a coleta foi aferida a glicemia pós-prandial dos pacientes. Obtivemos os seguintes resultados: Fluxo salivar médio geral de 0,21ml/min; mulheres com queixa 0,16 ml/min; e pacientes sem queixa 0,22ml/min. Capacidade tampão geral de 0,42; mulheres com queixa 0,46; pacientes sem queixa 0,40. Com relação ao pH média geral de 7,22; mulheres com queixa 7,0; pacientes sem queixa 7,22. Concentração de proteínas totais média geral 2,98mg/ml; mulheres com queixa 3,30 mg/ml; pacientes com queixa 2,88 mg/ml. Concluímos que a queixa de xerostomia é mais comum em mulheres e pacientes de maior idade, apresentando correlação positiva com fluxo salivar baixo, maior concentração proteica e maior consumo de medicamentos de uso crônico / The purpose of our trial was to investigate the influence of salivary flow rate, pH, protein content and buffer capacity over the symptom of xerostomia in a population of elderly people exhibiting good health. Eighty-five individuals were randomly selected, 13 men and 72 women, 60 to 82 years, mean 68.5. Twenty-one female patients presented dry mouth complaint when questioned. Seventy-seven patients (79%) were using some type of medication. Eighteen patients were not using drugs, 15 with no dry mouth complaint and three with xerostomia. Unstimulated whole saliva was collected for a period of 15 minutes to a refrigerated recipient. Salivary flow rate, pH and buffer capacity were measured immediately after sampling. Protein concentration was measured later at the lab center in a 2ml sample reserved for this procedure. Additionally, all patients had their glucose level taken. The following results were obtained: mean salivary flow rate of 0,21 ml/min, 0,16 for xerostomia patients and 0,22 for non-xerostomia patients. Mean salivary buffer capacity of 0,42; 0,46 for xerostomia patients and o,40 for non xerostomia patients. Mean pH of 7,22; 7,0 for xerostomia patients and 7,22 for non xerostomia patients. Mean protein concentration of 2,98 mg/ml; 3,30 for xerostomia patients and 2,88 for non xerostomia patients. We concluded that xerostomia is more prevalent in women and older patients, presenting positive correlation with low salivary flow rate, greater protein concentration and multiple drug use.
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Estudo da influência do solvente orgânico e do fluxo de injeção no controle de tamanho de nanocápsulas de núcleo lipídico preparadas através do método de deslocamento de solventeKlein, Alana Carina January 2013 (has links)
O fluxo de injeção e o solvente orgânico, utilizado no preparo de nanoesferas poliméricas, são parâmetros experimentais que controlam o diâmetro e a distribuição de diâmetro das nanopartículas, formadas pelo processo conhecido como nucleação. Considerando as nanocápsulas de núcleo lipídico, formadas pelo processo de auto-organização, estes parâmetros experimentais ainda não foram explorados. Assim, esse trabalho propõe avaliar o fluxo de injeção e o solvente orgânico na preparação destas suspensões aquosas, caracterizando físicoquimicamente estes sistemas. Para variação de fluxo de injeção, utilizou-se uma bomba peristáltica, sendo possível a avaliação dos seguintes fluxos: 5, 8, 12, 15, 21 e 38 mL min¯¹. O diâmetro das nanocápsulas diminuiu de 256±9 nm a 127 ±8 nm pela técnica de difração de laser e 220±9 nm a 124±13 nm, segundo a técnica de espectroscopia de correlação de fótons. Os solventes orgânicos avaliados foram a acetona, acetonitrila e 1,4-Dioxano. Observou-se que a acetonitrila se mostrou adequada para a condição previamente otimizada com acetona, ao passo que o 1,4-Dioxano apresentou um pico micrométrico em sua distribuição. Assim, foi possível modelar este estudo através de um fatorial de design 2², onde têm-se dois fatores, fluxo de injeção e solvente orgânico, em dois níveis, nos fluxos de 5 e 38 mL min¯¹ e considerando os solventes acetona e acetonitrila. Como resultado, viu-se que o fluxo de injeção é o parâmetro de maior influência na preparação destas suspensões aquosas, se comparado ao solvente orgânico selecionado. Para elucidar o papel do solvente orgânico na preparação destes sistemas, calculouse os parâmetros de solubilidade e os coeficientes de difusão solvente orgânico\água e água\solvente orgânico para os três pares avaliados neste trabalho. Viu-se que os parâmetros de solubilidade e os coeficientes de difusão solvente orgânico\água explicam a não variação do diâmetro de partícula em função do solvente orgânico. Ainda, realizou-se um estudo de viscosidade, em função do log [PCL], para fases orgânicas preparadas com acetonitrila e 1,4- dioxano. Obteve-se o valor de 2,30 mg mL¯¹ para a concentração de agregação crítica quando utilizado o 1,4-Dioxano e 10,47 mg mL¯¹ para a fase orgânica preparada com acetonitrila. Então, pode-se dizer que este valor elevado encontrado para a acetonitrila é uma vantagem de sua utilização, uma vez que as características nanoscópicas são mantidas e um maior número de partículas pode ser formado. / Flow rate and organic solvent, used to prepare polimeric nanospheres, are experimental parameters that control the size and the size distribution curves of these nanoparticles, formed by particle nucleation. Considering the lipid core nanocapsules, formed by self-assembled process, these experimental parameters are not evaluated yet. Considering those, this work proposes to evaluate the flow rate and the organic solvent in the preparation of these aqueous suspensions, characterizing them physicochemically. To change the flow rate, it was used a peristaltic pump, it being possible to evaluate the following flows: 5, 12, 15, 21 and 38 mL min‾¹. The nanocapsules diameters decreased from 256±9 nm to 127 ±8 nm, by laser difratometry and 220±9 nm to 124±13 nm, by the photon correlation spectroscopy technique. The organic solvents evaluated were acetone, acetonitrle and 1,4-dioxane. It was observed that the acetonitrile was adequate for the condition previously optimized with acetone, whereas in the 1,4-dioxane distribution apears a micrometric peak. So, it was possible to modelate this study by a 2² factorial design, two factors, flow rate and organic solvent, in two levels, 5 and 38 mL min‾¹, considering acetone and acetonitrile. As a result, it was seen that the flow rate is the most influential parameter in the preparation of aqueous suspensions, compared to organic solvent selected. To elucidate the role of organic solvent in these systems, it was calculated the solubility parameter and the diffusion coefficients organic solvent/water and water/organic solvent to the three pairs evaluated in this work. It was seen that the solubility parameter and diffusion coefficient organic solvent/water explain the same diameter of the nanocapsules, even the change on the organic solvent. Even so, it was done a viscosity study, as a function of log [PCL], to organic phases prepared with acetonitrile and 1,4-dioxane. It was obtained a value of 2,30 mg mL‾¹ to the critical aggregation concentration to the 1,4-dioxane solvent, and the value of 10,47 mg mL‾¹ to the acetonitrile solvent. So, it can be said that this high value found for acetonitrile is an advantage in its use, since the nanoscopic characteristics are maintained and a larger number of nanoparticles can be formed.
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Desempenho tÃcnico-financeiro de sistema hÃbrido eÃlico-solar aplicado ao bombeamento de Ãgua / Technical and financial performance of wind-solar hybrid system applied to water pumpingMarcelo Ferreira de Arruda 05 August 2015 (has links)
A presente dissertaÃÃo apresenta como objetivo principal a instalaÃÃo e avaliaÃÃo de desempenho tÃcnico-financeiro de um sistema hÃbrido eÃlico-fotovoltaico aplicado ao bombeamento de Ãgua. Adicionalmente, à proposta uma metodologia de dimensionamento de sistema hÃbrido de geraÃÃo baseado em fontes renovÃveis em funÃÃo do menor custo e do potencial disponÃvel. O sistema de geraÃÃo hÃbrido foi instalado na jusante do aÃude do Campus do Pici da Universidade Federal do Cearà (UFC), em Fortaleza/CE, Brasil. O sistema hÃbrido à composta por 01 aerogerador de 1 kW, 04 mÃdulos fotovoltaicos de 87 Wp, sistema de banco de baterias com 05 unidades de 150 Ah. O sistema de bombeamento à composto por um conjunto moto-bomba de 0,5 cv. A anÃlise tÃcnica foi efetuada mediante anÃlise dos dados (elÃtricos e nÃo elÃtricos) coletados atravÃs de sensores instalados a um sistema supervisÃrio. Os resultados indicam que a variaÃÃo do recurso eÃlico para o local à mais elevada, quando comparado ao recurso solar, e que a disponibilidade do potencial de ambos os recursos sÃo praticamente concomitantes ao longo do perÃodo diurno, caracterÃstica esta tambÃm observada no perÃodo analisado. O sistema de geraÃÃo com banco de baterias, operando tanto na configuraÃÃo hÃbrida ou individual, assegurou o fornecimento de eletricidade para o sistema de bombeamento no perÃodo de funcionamento da carga. A partir dos indicadores de eficiÃncia, verificou-se que as unidades de conversÃo apresentaram divergÃncia entre a geraÃÃo de eletricidade estimada e a mensurada, tendo a unidade eÃlica a qual apresentou maior divergÃncia. O custo da energia elÃtrica do sistema hÃbrido instalado (eÃlico-solar) com banco de baterias à de 0,86 R$/kWh. O dimensionamento do sistema de geraÃÃo indicou que a configuraÃÃo hÃbrida para o local nÃo se ajusta em virtude do elevado potencial solar disponÃvel e da baixa disponibilidade do recurso eÃlico no 1 trimestre do ano. O dimensionamento indicou que a configuraÃÃo hÃbrida foi a de menor custo (1,52 R$/kWh) quando dimensionada em funÃÃo dos recursos do mÃs de Outubro. Indicando assim que quando mais de uma fonte renovÃvel se destaca a configuraÃÃo hÃbrida pode ser sim uma alternativa viÃvel. / This work has as main objective the installation and technical
-
financial
evaluation of
a hybrid
wind
-
photovoltaic
system
applied to water
pumping
. In addition, a sizing methodology
is
proposed
based on renewable sources
considering low
cost and
available
potential. The hybrid
system
was installed in front of the Pici Campus
reservoir
of the Federal Univers
ity of CearÃ
(UFC) in Fortaleza
/CE, Brazil.
The hybrid system consists of 01 wind turbine of 1 kW, 04
photovoltaic modules of 87 Wp, a battery
bank with 05
units of 150 Ah.
The pumping system
con
sists of a motor
-
pump 0,
5 cv
.
Technical analysis was performed by analyzing the data
(electric and non
-
electric) collected by sensors to a supervisory
system.
The results indicate
that the wind resource variation for the
site
is higher, when compared to the solar resource,
and the availability
of
the potential of both resources are concomitant during the daytime
period, a characteristic also observed in the anal
yzed period.
T
he generation system with
battery bank, operating in
either the hybrid configuration or
individual, assured the supply of
electricity to the pumping system
during
operating time
.
From the indicators of efficiency, it
was found that the conver
sion units showed divergence between estimated
and measured
electricity generation, and wind unit which presented greater divergence.
The
electricity
cost
of
the hybrid system (wind
-
solar)
installed with battery bank is 0.86 R$/kWh.
The sizing
of
the generating system indicated
that the hybrid configuration at
the
site
does not fit due to the
high solar potential available and the low availability of wind resources in the 1
st
trimester
of
the year
.
The
sizing generation system indicated that th
e
hybrid configuration has the lowest
cost (1.52 R$/kWh) when sizing with the
resources of
October
month
.
Indicating thus
,
that
when more than one renewable source stands out
,
the hybrid configuration can be viable
alternative
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Avaliação da deposição da calda de pulverização em função do tipo de ponta e do volume de aplicação, na cultura da soja / Evaluation the sprying syrup deposition in function of the beak type and the flow, in soybeanBoschini, Laercio 29 September 2006 (has links)
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Previous issue date: 2006-09-29 / The soybean has great economical importance in Brazilian agribusiness, and the cultivation with high profitability, it is necessary the use all available technologies in the market and, among them, it is the application technology of agricultural pesticide, that it looks tirelessly for the best technique of the product biologically active it reaches the objective, providing for the effective control of the harmful plant, insect or mushroom, allowing the plant express all the productive potential, when appropriately nurtured and in good environmental conditions. Due to those needs the present work was carried out in Cascavel PR, in the harvest 2004/2005, using the soybean cultivar CD 202, with the objective evaluating the amount spray deposited on the soybean leaves, varied the flow rate applied and the nozzles types used in the spraying boom, used tracer substance, simulating the physical characteristics of the solutions of the products. To evaluate the spraying distribution, fifteen leaves were collected per plant in different extracts (upper, medium and lower), with the purpose of evaluating the syrup penetration, in agreement with the different beaks and applied volumes. The experimental design was arranged in randomized complete blocks, in factorial arrangement, with four beaks and point of the type single fan, double fan, double fan with air induction and rollowcone and 3 syrup volumes (100, 200 and 300 L ha-1). In agreement with the results obtained and in the conditions that the present work was carried out.
- The syrup volume that presented larger depositions, in the different levels was 300 L ha-1.
- The spraying that presented larger depositions, in the higher levels plants was the double fan nozzles and, for the medium and lower extracts, was the rollowcone nozzle.
- The depositions happened in the thirds medium and lower of the soybeans plants were lower significantly to obtained them in the upper third, independently the and the flow rate that was used.
- For larger depositions in the upper third of the soybeans plants, the best combination is to use of double plane jet, with of 300 L.
- For larger depositions in the medium and lower third of the soybeans plants, the best combination is to use of rollowcone, with flow rate of 200 or 300 L ha-1 / A cultura da soja tem grande importância econômica no agronegócio brasileiro, sendo que, para seu cultivo com alta rentabilidade, faz-se necessário o uso de todas as tecnologias disponíveis no mercado e, dentre elas, está à tecnologia de aplicação de defensivos agrícolas, que busca incansavelmente a melhor técnica para que o produto biologicamente ativo atinja o alvo, proporcionando controle eficaz da planta daninha, inseto ou fungo, permitindo à planta expressar todo o seu potencial produtivo, quando adequadamente nutrida e em boas condições ambientais. Diante dessas necessidades foi conduzido o presente trabalho no município de Cascavel PR, na safra de 2004/2005, utilizando o cultivar de soja CD 202, com o objetivo de avaliar a quantidade de calda depositada nas folhas da soja, variando o volume de calda aplicada e os tipos de pontas utilizados na barra de pulverização, utilizando-se substância traçadora, simulando as características físicas das soluções de produtos fitossanitários. Para avaliar a distribuição da pulverização, foram coletadas três folhas por planta em diferentes extratos (superior, mediano e inferior), com a finalidade de avaliar a quantidade de depósito de calda, de acordo com as diferentes pontas e volumes aplicados. O delineamento experimental constituiu-se de blocos ao acaso, em arranjo fatorial, compreendendo 4 pontas de pulverização (leque simples, duplo leque, duplo leque com indução de ar e cone vazio) e 3 volumes de calda (100, 200 e 300 L ha-1 ). De acordo com os resultados obtidos e nas condições em que o presente trabalho foi conduzido, concluiu-se que: o volume de calda que apresentou maiores deposições, nos diferentes extratos das plantas de soja foi o de 300 L ha-1; a ponta de pulverização que apresentou maiores deposições no extrato superior das plantas, foi a de duplo leque e, para os extratos mediano e inferior, a ponta cone vazio; as deposições ocorridas nos extratos mediano e inferior das plantas de soja foram significativamente inferiores às obtidas no extrato superior, independentemente da ponta e do volume de aplicação utilizado; para maiores deposições no extrato superior das plantas de soja, a melhor combinação é utilizar pontas duplo leque, com volumes de calda de 300 L ha-1; para maiores deposições no extrato mediano e inferior das plantas de soja, a melhor combinação é utilizar pontas de cone vazio, com volumes de calda de 200 ou 300 L ha-1
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Estudo da influência do solvente orgânico e do fluxo de injeção no controle de tamanho de nanocápsulas de núcleo lipídico preparadas através do método de deslocamento de solventeKlein, Alana Carina January 2013 (has links)
O fluxo de injeção e o solvente orgânico, utilizado no preparo de nanoesferas poliméricas, são parâmetros experimentais que controlam o diâmetro e a distribuição de diâmetro das nanopartículas, formadas pelo processo conhecido como nucleação. Considerando as nanocápsulas de núcleo lipídico, formadas pelo processo de auto-organização, estes parâmetros experimentais ainda não foram explorados. Assim, esse trabalho propõe avaliar o fluxo de injeção e o solvente orgânico na preparação destas suspensões aquosas, caracterizando físicoquimicamente estes sistemas. Para variação de fluxo de injeção, utilizou-se uma bomba peristáltica, sendo possível a avaliação dos seguintes fluxos: 5, 8, 12, 15, 21 e 38 mL min¯¹. O diâmetro das nanocápsulas diminuiu de 256±9 nm a 127 ±8 nm pela técnica de difração de laser e 220±9 nm a 124±13 nm, segundo a técnica de espectroscopia de correlação de fótons. Os solventes orgânicos avaliados foram a acetona, acetonitrila e 1,4-Dioxano. Observou-se que a acetonitrila se mostrou adequada para a condição previamente otimizada com acetona, ao passo que o 1,4-Dioxano apresentou um pico micrométrico em sua distribuição. Assim, foi possível modelar este estudo através de um fatorial de design 2², onde têm-se dois fatores, fluxo de injeção e solvente orgânico, em dois níveis, nos fluxos de 5 e 38 mL min¯¹ e considerando os solventes acetona e acetonitrila. Como resultado, viu-se que o fluxo de injeção é o parâmetro de maior influência na preparação destas suspensões aquosas, se comparado ao solvente orgânico selecionado. Para elucidar o papel do solvente orgânico na preparação destes sistemas, calculouse os parâmetros de solubilidade e os coeficientes de difusão solvente orgânico\água e água\solvente orgânico para os três pares avaliados neste trabalho. Viu-se que os parâmetros de solubilidade e os coeficientes de difusão solvente orgânico\água explicam a não variação do diâmetro de partícula em função do solvente orgânico. Ainda, realizou-se um estudo de viscosidade, em função do log [PCL], para fases orgânicas preparadas com acetonitrila e 1,4- dioxano. Obteve-se o valor de 2,30 mg mL¯¹ para a concentração de agregação crítica quando utilizado o 1,4-Dioxano e 10,47 mg mL¯¹ para a fase orgânica preparada com acetonitrila. Então, pode-se dizer que este valor elevado encontrado para a acetonitrila é uma vantagem de sua utilização, uma vez que as características nanoscópicas são mantidas e um maior número de partículas pode ser formado. / Flow rate and organic solvent, used to prepare polimeric nanospheres, are experimental parameters that control the size and the size distribution curves of these nanoparticles, formed by particle nucleation. Considering the lipid core nanocapsules, formed by self-assembled process, these experimental parameters are not evaluated yet. Considering those, this work proposes to evaluate the flow rate and the organic solvent in the preparation of these aqueous suspensions, characterizing them physicochemically. To change the flow rate, it was used a peristaltic pump, it being possible to evaluate the following flows: 5, 12, 15, 21 and 38 mL min‾¹. The nanocapsules diameters decreased from 256±9 nm to 127 ±8 nm, by laser difratometry and 220±9 nm to 124±13 nm, by the photon correlation spectroscopy technique. The organic solvents evaluated were acetone, acetonitrle and 1,4-dioxane. It was observed that the acetonitrile was adequate for the condition previously optimized with acetone, whereas in the 1,4-dioxane distribution apears a micrometric peak. So, it was possible to modelate this study by a 2² factorial design, two factors, flow rate and organic solvent, in two levels, 5 and 38 mL min‾¹, considering acetone and acetonitrile. As a result, it was seen that the flow rate is the most influential parameter in the preparation of aqueous suspensions, compared to organic solvent selected. To elucidate the role of organic solvent in these systems, it was calculated the solubility parameter and the diffusion coefficients organic solvent/water and water/organic solvent to the three pairs evaluated in this work. It was seen that the solubility parameter and diffusion coefficient organic solvent/water explain the same diameter of the nanocapsules, even the change on the organic solvent. Even so, it was done a viscosity study, as a function of log [PCL], to organic phases prepared with acetonitrile and 1,4-dioxane. It was obtained a value of 2,30 mg mL‾¹ to the critical aggregation concentration to the 1,4-dioxane solvent, and the value of 10,47 mg mL‾¹ to the acetonitrile solvent. So, it can be said that this high value found for acetonitrile is an advantage in its use, since the nanoscopic characteristics are maintained and a larger number of nanoparticles can be formed.
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Vyhodnocení jakosti vody a odtokových poměrů na povodí Jenínského toku. / Evaluation of water quality and runoff characteristics in the Jenínský stream catchment.KROPÁČEK, Robin January 2012 (has links)
The aim of this thesis is to evaluate water quality and runoff characteristics in the Jenínský stream catchment. For this purpose analysis and data processing was performed. Two subcatchments, called J1 and J2, were monitored at this catchment area. Period of interest involves years 2008-2012. Results were compared with the period 1983-1985 when most of the land was used as arable land. The decrease in the concentrations of all evaluated indicators was caused by grassing and reduction in the use of fertilisers. Ranges of the values of selected indicators also decreased distinctly and their concentrations are stabilized. The greatest decrease of 79% (J1) and 87% (J2) was found in average ammonium concentrations. A beneficial effect of land use change to extensive agricultural management on water quality was proven.
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