Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-30T13:42:44Z No. of bitstreams: 1 JOÃO DE DEUS DOS SANTOS - DISSERTAÇÃO PPGECA 1977..pdf: 21984806 bytes, checksum: 0525fd994fc74fd425d9748a384f468a (MD5) / Made available in DSpace on 2018-09-30T13:42:44Z (GMT). No. of bitstreams: 1 JOÃO DE DEUS DOS SANTOS - DISSERTAÇÃO PPGECA 1977..pdf: 21984806 bytes, checksum: 0525fd994fc74fd425d9748a384f468a (MD5) Previous issue date: 1977-07 / O estudo apresentado nesta dissertação trata da consolidação de uma argila mole da cidade de João Pessoa, Estado da Paraíba, Brasil. Para a determinação das propriedades de consolidação foram realizados ensaios de adensamento no aparelho edométrico, com amostras indeformadas, representativas de diversas profundidades da camada de argila. Também realizou-se ensaios de caracterização da argila, em termos de plasticidade, granulometria e pesos específicos. Os parâmetros de consolidação e os parametros de consistência da argila obtidos durante o programa de laboratório foram analisados em relação as suas variações com a profundidade. Os resultados desta análise, mostram que o coeficiente de consolidação Cv e o coeficiente de permeabilidade K, do solo estudado, são praticamente constantes ao longo da camada, enquanto que o coeficiente de compressibilidade av, o índice de compressão Cc e os índices de vazios, decrescem com a . profundidade. Estes resultados permitiram também formular relações matemáticas, algumas delas com notável validade estatística, permitindo consequentemente a sua utilização em anteprojetos de Engenharia Civil. / The study presented in this dissertation concerns the consolidation of a soft clay from the city of João Pessoa, in the State of Paraíba, Brazil. The consol i dation properties were deter mined by means of consolidation tests in an oedometer, with undisturbed samples representative of various depths within the clay layer. Tests were also performed in order to determine the clay cha rac ter i s t i es , in terms of plasticity, grain size and specific gravity. The parameters of consol i da ti on and coji sistency obtained during the laboratory program were analyzed in relation to their variation as a function of depth. The results of this analysis show that the coefficient of consol idation Cy and the coefficient of permeability K, of the soil which was studied are practically constant throughout the layer, while the coefficient of compressibility av, the compressive index Cc, and void ratio decrease with increase of depth. These results also permit the formulation of mathematical reiationships, some of them showing notable statistical validity, thus permitting their use in civil engineering designs.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The pepper (Capsicum annuum L.) has commercial importance, by having sources of vitamins, minerals and fiber. However, a post-harvest problem, excessive softening which reduces the life and favors action pathogens such as Pectobacterium caratovorum subsp. caratovorum- Pcc, causal agent of soft rot, a major disease of post-harvest chili that is favored by the reduction of firmness. One technique that has recently been used for firmly maintaining the application is pectin methyl esterase (PME) with the addition of a calcium solution prologando thus reducing its lifetime and pathogen attack. The objective of this study was to use methyl pectin esterase (PME) exogenous associated with calcium chloride in maintaining firmness and control of Pectobacterium caratovorum subsp. caratovorum about pepper. The first experiment was conducted in a completely randomized design in a 4x5 factorial scheme with three replications for 12 days, evaluated every three days. In the second experiment, the test was conducted in a completely randomized design in a factorial 5x5 with three replications. In the first study the fruits of pepper were subjected to vacuum infusion method with pressure of 200 mmHg for 5 minutes, and following evaluated the loss of weight (PMF), fruit firmness (FF), skin color ( CC), soluble solids (SS), pH, total acidity (TA) and activity of SMEs. In the second test the fruits of pepper were subjected to vacuum infusion method with pressure of 200 mmHg for five minutes, then the fruits were inoculated with the PCC then held the fruit firmness analysis (FF), SME activity and the severity of the disease in chili (SD). The fruits obtained in general a reduction of over time firmly in all treatments but was found significant effect in maintaining the fruit firmness when treated in vacuum infusion with calcium chloride, without altering the physicochemical characteristics, as soluble solids content, total acidity and activity of SMEs, slowing the fruit ripening process. The fruits when treated with vacuum infusion with calcium chloride associated with pectin methyl esterase was not favorable because it altered the physicochemical properties chili, highlighting the decline of firmness, thus deteriorating the quality of the fruit. Regarding inoculation Pcc in the fruit was observed inhibition of growth of this pathogen, prolongation of fruit and better firmness treated fruits infusion over calcium inoculation Pcc chloride. / O pimentão (Capsicum annuum L.) tem grande importância comercial, por possuir fontes de vitaminas, minerais e fibras. Contudo, possui problema pós-colheita, o amolecimento excessivo que reduz a vida útil e favorece ação de patógenos como a Pectobacterium caratovorum subsp. caratovorum- Pcc, agente causal da podridão-mole, uma das principais doenças da pós-colheita do pimentão que é favorecida pela redução da firmeza. Uma técnica que vem sendo utilizada recentemente para a manutenção da firmeza é aplicação da pectina metil esterase (PME) com a adição de solução de cálcio prologando, assim, a sua vida útil e diminuindo o ataque do patógeno. Assim, o objetivo do trabalho foi utilizar a pectina metil esterase (PME) exógena associada ao cloreto de cálcio na manutenção da firmeza e no controle da Pectobacterium caratovorum subsp. caratovorum sobre o pimentão. O primeiro experimento foi realizado em delineamento inteiramente casualizado em esquema fatorial 4x5 com três repetições, durante 12 dias, avaliados a cada 3 dias. No segundo experimento, o ensaio foi realizado em delineamento inteiramente casualizado no esquema fatorial 5x5 com três repetições. No primeiro trabalho os frutos de pimentão foram submetidos ao método de infusão a vácuo com pressão de 200 mmHg por 5 minutos, e por seguinte avaliou-se a perda de massa fresca (PMF), firmeza do fruto (FF), cor da casca (CC), teor de sólidos solúveis (SS), pH, acidez total, (AT) e atividade de PME. No segundo ensaio os frutos de pimentão foram submetidos ao método de infusão a vácuo com pressão de 200 mmHg por cinco minutos, posteriormente os frutos foram inoculados com a Pcc em seguida realizou-se as análises de firmeza do fruto (FF), atividade de PME e a severidade da doença no pimentão (SD). Os frutos obtiveram de forma geral uma redução da firmeza ao longo do tempo em todos os tratamentos, porém foi verificado o efeito significativo na manutenção da firmeza dos frutos quando tratados em infusão a vácuo com cloreto de cálcio, não alterando as características físico-químicas, como o teor de sólidos solúveis, acidez total e atividade de PME, retardando o processo de amadurecimento do fruto. Os frutos quando tratados com infusão a vácuo com cloreto de cálcio associado à pectina metil esterase não foi favorável, pois alterou as propriedades físico-químicas do pimentão, com destaque para o declínio da firmeza, deteriorando assim a qualidade do fruto. Em relação à inoculação da Pcc no fruto, observou-se uma inibição do crescimento desse patógeno, prolongamento do fruto e uma melhor firmeza nos frutos tratados com infusão de cloreto de cálcio mais a inoculação da Pcc.

A utilização de métodos de análise apoiados na Teoria da Equação da Onda, a partir da instrumentação de medidas dinâmicas, como controle do comportamento de estacas, tem evoluído continuamente nos últimos anos. Após importantes considerações sobre a prova de carga dinâmica de energia crescente e o mecanismo de transferência de carga, procedem-se análises CAPWAP em um caso real de obra com o objetivo de analisar o comportamento do sistema estaca-solo perante a aplicação de níveis crescentes de energia. São apresentados nesta dissertação, os resultados do comportamento de vários sistemas isolados estaca-solo em maciço de argila mole, submetidos à prova de carga dinâmica de energia crescente. São feitas análises de: transferência de carga, atrito lateral local, quake da ponta, tensões dinâmicas e correlação entre prova de carga estática e dinâmica. / The use of analysis methods to control pile behavior employing the Stress-Wave Theory from results of dynamic pile driving measurements has evolved in recent years. After important considerations about the increasing energy dynamic loading test and the load transfer mechanism, CAPWAP analyses are proceed in a pilework with objective of analyzing the behavior of the pile-soil system before the application of growing levels of energy. Therefore, they are presented in this dissertation, the results of the behavior of several isolated pile-soil systems in soft clay formation, submitted to the dynamic loading test of growing energy. Among the analyses, load transfer diagrams, local friction, quake, dynamic tensions, and the correlation between static and dynamic loading test are presented.

O decorim e o biglicam são membros da família dos pequenos proteoglicanos ricos em leucina e possuem importantes funções no controle da proliferação, migração e invasão do citotrofoblasto extraviloso (TEV). O objetivo deste trabalho foi de caracterizar a expressão diferencial e a imunolocalização de decorim e biglicam em placentas humanas normais a termo (PNT), na placenta acreta (PA), na mola invasora (MI) e no coriocarcinoma (CO). Na PNT, as células deciduais apresentaram positividade para o decorim, enquanto o TEV foi negativo. O decorim foi fracamente expresso na matriz endometrial, mas negativo no fibrinoide do tipo matriz, enquanto foi positivo para biglicam. Na PA e na MI, o TEV mostrou positividade para decorim e biglicam. No CO, somente o citotrofoblasto foi positivo para ambos proteoglicanos. Portanto, o decorim e o biglicam são expressos diferencialmente em placentas normais e patológicas, sugerindo que os padrões de expressão desses proteoglicanos nas patologias estudadas indicam um papel na modulação da migração e da invasão do trofoblasto. / Decorin and biglycan are family members of the small leucine-rich proteoglycans family, and they have many functions as controlling proliferation, migration and invasion of extravillous trophoblast cells (EVT). The aim of this study was to characterize decorin and biglycan differential expression and immunolocalization in human normal term placenta (NTP), in placenta accreta (PA), in invasive mole (IM), and in choriocarcinoma (CH) samples. In PNT, deciduas cells were positive to decorin whereas EVT was negative. Decorin was faintly stained at endometrial matrix, but negative at matrix-type fibrinoid, although it was positive for biglycan. In PA and IM, the EVT was positive for decorin and biglycan. In CH, only cytotrophoblast cells were positive for both proteoglycans. Therefore, decorin and biglycan are differentially expressed in normal placenta and in placenta pathologies, suggesting that the expression patterns of the proteoglycans in studied pathologies indicate a role in modulating trophoblast migration and invasion.

The purpose of the study was to investigate grade 11 learners’ problem solving skills and conceptual reasoning on concepts in stoichiometry. Two theoretical frameworks were used in this study namely, cognitive load theory (CLT) and typology of curriculum representation (levels of curriculum alignment). The explanatory sequential mixed method research design were applied where 410 physical sciences learners in their intact classes and eleven of their teachers participated in the study. The participants completed purposefully designed research instruments consisting of an achievement test (LAT), a teacher and a learner questionnaire (TSQ and LCQ), and a teacher lesson plan on stoichiometry-related concepts (TLP). Other instruments used include a semi-structured interview schedule (LIS), classroom observation schedule (COS) and learner work books (LWB). The study was underpinned by five research questions. Pearson correlations showed that the justifications given by learners for choosing right or wrong objective options were not due to chance and suggested a learner choosing the right objective option has the right conceptual reasoning. Findings indicate that there is a positive correlation between problem-solving skills and conceptual reasoning where conceptual reasoning statistically predicted learners’ problem-solving skills using Regression. Problem solving is an important cognitive activity in everyday and professional contexts. Therefore, it requires teachers to know where to focus their teaching and how to assess learners’ work to avoid unnecessary overloading of the working memory of learners which might affect their performance. Conceptual reasoning and problem-solving errors were made during the problem solving, for example, learners could not apply mole ratio, they were unable to do change of subject and they interchanged the meanings of chemical terms such as mole, molecule, atoms and mass. In terms of possible reasons for the errors, and how it linked to the way learners were taught, the curriculum levels were considered. Findings indicate that there is a mismatch between what is expected in stoichiometry from the CAPS curriculum termed intended curriculum and the implemented curriculum which includes teacher lesson plans, classroom observations and learner workbooks. The classroom observations schedule was designed in line with the teacher lesson plan. There were topics planned in the lessons that were not found in the learner workbooks. The analysis of the content of learners’ workbooks for topics treated under stoichiometry, revealed that 75.7% of concepts were being taught while 24.3% were not. The analysis showed that learners experienced difficulties with calculating the concept of limiting reactant. There is a mismatch between implemented and attained curriculum as well. In the TSQ, teachers indicated that the errors were due to misconceptions, misunderstanding, carelessness and misinterpretation. These were found during marking of the learner achievement test. In conclusion, this study did not find a direct link between the way the learners were taught and the errors they committed during problem solving based on the implemented (TLP, LWB and COS) and attained curriculum (LAT, LCQ, LIS and DoBE report) / Science and Technology Education / Ph. D. (Mathematics, Science and Technology Education)

Liquefied Natural Gases (LNG) has been an alternative fuel in the marine industry for several years, but lately, the amount of ships that have been powered by methane has increased a lot. Some of the reasons for this is because LNG does not contain any sulfur and releases less nitrogen oxides than traditional maritime fuels. In this essay, LNG will be compared to diesel from an environmental perspective with focus on CO2 emissions and its equivalents. International Maritime Organization (IMO) implemented Energy Efficiency Design Index (EEDI) requirements that adjusts how much CO2 is allowed in the exhaust gas per produced kilowatt-hour (kWh). However, these requirements will increase in intervals in the future, the next one is coming 2022 for specific ship types. The method that is used to compare the fuels is Mole-calculations for LNG as well as diesel, then calculate the amount of carbon dioxide (CO2) and its equivalents they release. The results show that under optimal conditions, LNG was the superior choice. However, the maritime industry might have a problem with the requirements that will be introduced to greenhouse gas (GHG) emissions in 2050. / Flytande Naturgas (LNG) har under flera år funnits som ett alternativt bränsle inom sjöfarten, men på senare tid så har skeppen som drivs av metan ökat markant. En anledning till detta är att LNG innehåller inget svavel samt släpper ut mindre NOX jämfört med traditionella bränslen. I denna uppsats så kommer LNG att jämföras mot diesel ur ett klimatperspektiv med fokus på koldioxidutsläpp och dess ekvivalenter. International Maritime Organisation (IMO) har infört Energy Efficiency Design Index (EEDI) krav som justerar hur mycket CO2 man får släppa ut per kilowattimme (kWh), dessa krav kommer dessutom att öka i flertalet intervaller i framtiden, varav nästa intervall redan sker i 2022 för speciella fartygstyper. Metoden som användes för att jämföra bränslena var att beräkna mol-innehållet för både LNG samt diesel, sen från den beräknade data se hur mycket koldioxid (CO2) inklusive ekvivalenter de släppte ut. Resultatet visade att under optimala förutsättningar så var LNG ett klart bättre alternativ än diesel. Däremot så kan sjöfarten ha ett problem inom framtiden från de krav som berör växthusgaser som kommer att ställas från och med 2050.

<p>  </p> <p>Part I studies the lubricant sprays and droplets in a rotary compressor. Air conditioning (AC) systems are now widely used in residential and commercial environments, while the compressor is the most important element in the AC system, and rotary compressors are often used in split AC appliances, whose number is estimated to reach 3.7 billion in 2050. In a rotary compressor, the lubricant oil atomizes into small droplets due to the differential pressure in and out of the cylinder. Part of the lubricant oil droplets carried by the refrigerant vapor will ultimately exhaust from the compressor through the discharge pipe. The ratio of the discharged oil volume to the total oil volume is characterized as the Oil Discharge Ratio (ODR). High ODR will reduce the reliability of the compressor and deteriorate the heat transfer of the condenser and the evaporator, resulting in decreased efficiency. Thus, controlling the ODR is a key issue for the design of the rotary compressor.</p> <p>In Part I, rotary compressors were modified to provide optical access into its internal space, i.e., the lower cavity (refers to the space between the cylinder and the motor), above the rotor/stator, and at the discharge tube level. The modified rotary compressors’ operation was supported by a test rig which provided a wide range of operating conditions, e.g., pressure and frequency. Thus, in-situ optical measurements, e.g., shadowgraph and holograph, can be performed to visualize the lubricant sprays and droplets in the rotary compressor. An image processing routine containing the Canny operator and Convolutional Neural-Network was developed to identify droplets from high-resolution shadowgraph images, while Particle Image Velocimetry (PIV) and Optical Flow Velocimetry (OFV) were applied to calculate the spray and droplet’s velocities with time-resolved shadowgraph images. Parallel Four-Step Phase Shifting Holograph (PFSPSH) located the droplets’ positions in a three-dimensional volume under the specific operating condition.</p> <p>Both primary and secondary atomization were observed in the rotary compressor, while primary atomization is the major source of droplet production. The droplet size distributions versus the frequency, vertical direction, radial direction, and pressure are obtained. It is observed that the droplet characteristic mean diameters increase with the frequency and pressure. They also become larger in the outer region above the rotor/stator and keep constant in the radial direction at the discharge tube level. The penetration velocity of the lubricant spray is calculated in the lower cavity. An outward shift of the jet core combined with an outward velocity component was observed. Additionally, horizontal swirling velocity above the rotor/stator and at the discharge tube level and the vertical recirculation velocity above the rotor/stator are characterized. The volume fraction of droplets was also characterized under the specific operating condition. The results provide detailed experimental data to set up the boundary conditions used in CFD. They also show that the droplets in the upper cavity are mostly from the discharge process of the cylinder in the lower cavity. The results support a droplet pathway model in the rotary compressor, which can guide the optimization of future rotary compressors.</p> <p>Evaporation is commonly seen in hydrology, agriculture, combustion, refrigeration, welding, etc. And it always accompanies heat and mass transfer at the liquid-gas interface and is affected by the substance’s properties, the environment’s pressure, temperature, convection, and so on. PFSPSH in Part I aims to retrieve the phase information for holograph reconstruction. Part II further explores the application of the PFSPSH technology in Part I to observe the evaporation process of acetone, where the phase disturbance caused by the vapor is used to reconstruct the vapor concentration in space. The method is called Parallel Four-Step Phase Shifting Interferometer (PFSPSI). The first case studies the evaporation process of the acetone contained in a liquid pool with uniform air flow in a low-speed wind tunnel. The mole fractions of the acetone vapor near the liquid-air interface with different air speeds are characterized. The second case studies the evaporation process of acetone droplets levitated by an ultrasound levitator. The mole fraction of the acetone vapor near the liquid-air interface is characterized by assuming an axisymmetric field and using the analytical solution of the inverse Abel transform. The asymmetric pattern of the acetone vapor field is observed, which is considered due to the drastic sound pressure change at the stand wave location produced by the ultrasound levitator. The mass transfer of the evaporation process by the vapor’s mole fraction is calculated and compared with the mass transfer calculated by the droplet size change. It is observed that the mass transfer by the vapor’s mole fraction is generally smaller than the mass transfer calculated by the droplet size change, which can be explained by the convection process induced by the acoustic streaming.</p>