414 resultados para Tray dryer


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This work treats the thermal and mechanical performances of gas-filled, flat plate solar collectors in order to achieve a better performance than that of air filled collectors. The gases examined are argon, krypton and xenon which all have lower thermal conductivity than air. The absorber is formed as a tray connected to the glass. The pressure of the gas inside is near to the ambient and since the gas volume will vary as the temperature changes, there are potential risks for fatigue in the material. One heat transfer model and one mechanical model were built. The mechanical model gave stresses and information on the movements. The factors of safety were calculated from the stresses, and the movements were used as input for the heat transfer model where the thermal performance was calculated. It is shown that gas-filled, flat plate solar collectors can be designed to achieve good thermal performance at a competitive cost. The best yield is achieved with a xenon gas filling together with a normal thick absorber, where normal thick means a 0.25 mm copper absorber. However, a great deal of energy is needed to produce the xenon gas, and if this aspect is taken into account, the krypton filling is better. Good thermal performance can also be achieved using less material; a collector with a 0.1 mm thick copper absorber and the third best gas, which is argon, still gives a better operating performance than a common, commercially produced, air filled collector with a 0.25 mm absorber. When manufacturing gas-filled flat plate solar collectors, one way of decreasing the total material costs significantly, is by changing absorber material from copper to aluminium. Best yield per monetary outlay is given by a thin (0.3 mm) alu-minium absorber with an argon filling. A high factor of safety is achieved with thin absorbers, large absorber areas, rectangular constructions with long tubes and short distances between glass and absorber. The latter will also give a thin layer of gas which gives good thermal performance. The only doubtii ful construction is an argon filled collector with a normal thick (> 0.50 mm) aluminium absorber. In general, an assessment of the stresses for the proposed construction together with appropriate tests are recommended before manufacturing, since it is hard to predict the factor of safety; if one part is reinforced, some other parts can experience more stress and the factor of safety actually drops.

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Värmedrivna vitvaror eller HWC-maskiner som de kallas av tillverkaren värms med varmt vatten från en cirkulerande krets via en värmeväxlare inbyggd i maskinen, till skillnad från konventionella maskiner som värms med el. Denna teknik skall inte förväxlas med maskiner som är anslutna till varmvattenledningen och fylls på med varmt vatten och som därmed begränsas till disk- och tvätt. Syftet med fjärrvärmedrivna vitvaror är alltså att använda fjärrvärme, som har lägre kvalitet och pris än elenergi för uppvärmning och torkning och på så sätt spara el och utöka fjärrvärmeunderlaget. En jämförelse av koldioxidutsläpp och primärenergianvändning mellan konventionella vitvaror och fjärrvärmedrivna vitvaror visar att både koldioxidutsläpp och primärenergianvändning blir lägre för fjärrvärmedrivna vitvaror om biobränsle anses koldioxidneutralt och den el som ersätts är producerad i kolkraftverk eller gaskombikraftverk.   Denna rapport beskriver utveckling och kommersialisering av värmedrivna vitvaror (disk- och tvättmaskiner samt torktumlare och torkskåp) och hur de kan anslutas mot fjärrvärmesystem i olika systemlösningar. Dessutom har de energimässiga och ekonomiska förutsättningarna för tekniken undersökts. Erfarenheterna från fältprovning är dock mycket begränsade, eftersom de byggen där fälttesterna skulle ske försenades. Under 2013 färdigställs ett flerbostadshus med värmedrivna vitvaror i 160 lägenheter i Västerås.   De utvecklade maskinernas värmeanvändning som andel av total energianvändning vid 60 graders framledningstemperatur har uppmätts till ca 50 % för diskmaskinen, 67 % för tvättmaskinen, 80 % för torktumlaren och 93 % för torkskåpet. I det studerade flerbostadshuset av passivhusstandard uppgår lasten från värmedrivna vitvaror komfortgolvvärme och handdukstorkar till upp mot 30 % av husets totala värmeanvändning. För småhus är motsvarande siffra upp mot 20 %. Att använda fjärrvärme istället för elvärme till dessa installationer som normalt är elvärmda kan allts minska elbehovet betydligt i lågenergibebyggelse vilket också minskar både koldioxidutsläppen och primärenergianvändningen.   Ekonomiska analyser har genomförts för två olika systemkoncept (separat vitvarukrets och Västeråsmodellen) för nybyggda småhusområden och flerfamiljshus där fjärrvärme inte bara används till vitvaror utan också till handdukstorkar och komfortgolvvärme. De ekonomiska analyserna visar att Västeråsmodellen är den mest ekonomiskt intressanta systemlösningen med värmedrivna vitvaror, handdukstork och komfortgolvvärme. I flerfamiljshus kan den vara konkurrenskraftig mot de elvärmda alternativen (konventionellt system med eldrivna vitvaror, komfortgolvvärme och handdukstorkar) om prisskillnaden mellan el och fjärrvärme är större än 0,7 kr/kWh. En parameterstudie visar att kapitalkostnaden blir ganska hög jämfört med energikostnaden, vilket betyder att lång livslängd och många cykler är viktigt för att förbättra de ekonomiska förutsättningarna för värmedrivna vitvaror. För passiva småhus blir kostnaden för Västeråsmodellen med värmedrivna vitvaror, handdukstork och komfortgolvvärme likvärdig med de elvärmda alternativen vid energiprisskillnader på 0,7 kr/kWh inklusive moms, medan det krävs prisskillnader på 0,9 kr/kWh inklusive moms för normalisolerade småhusområden.   Sammanfattningsvis kan sägas att i kommuner med ett konkurrenskraftigt fjärrvärmepris finns det viss lönsamhet för hela konceptet enligt Västeråsmodellen med värmedrivna vitvaror, komfortgolvvärme, och handdukstorkar. Om man däremot ser på konkurrensen för enskilda vitvaror är det främst torktumlaren som är konkurrenskraftig i bostäder. Målpriset på 1000 kr extra för värmedrift har inte kunnat uppnås inom projektet för diskmaskiner och tvättmaskiner. Det krävs lägre priser och låga anslutningskostnader för att räkna hem diskmaskinen och tvättmaskinen som enskilda komponenter.   Värmedrivna tvättmaskiner och torktumlare är konkurrenskraftiga i flerfamiljstvättstugor. Speciellt i de fall där beläggningen är god och flera maskiner delar på anslutningskostnaden till fjärrvärmecentralen kan värmedrift bli riktigt lönsam. Torkskåpens konkurrenskraft har inte kunnat utvärderas, då priset ännu inte fastställts. Att använda VVC-systemet för värmedistribution till värmedrivna vitvaror kan vara mycket intressant, men det kräver att legionellaproblematiken kan lösas. I nuläget finns ingen lösning som uppfyller formuleringarna i boverkets byggregler. Ett annat distributionssätt som kan vara intressant, men som inte undersökts i studien är att använda VVC för varmvattendistribution och en gemensam radiator- och vitvarukrets med konstant framledningstemperatur. Den aktör som förväntas ha störst ekonomiskt intresse av att tekniken implementeras är sannolikt fjärrvärmebolagen som får sälja mer värme och det ligger därmed främst på deras ansvar att marknadsföra tekniken i mötet med sina kunder.

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MACHADO, Antônio V. et al. Estudio del Secado de Anacardo (Anacardium occidentale L.) mediante Secador Solar de Radiación Directa. Información Tecnológica, v. 21, n. 1, p. 31-37, 2010.

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Arthropods are abundant organisms possess great wealth and diversity representing about 82% of all known animal species. Contribute as a source of biomass and their abundance is an indicator of ecological change. The aim of this study was to evaluate the biomass and abundance found in the salt marsh environment throughout the year and relate them to the climatic factors (temperature, precipitation and relative humidity) that can influence the abundance and biomass of arthropods. The study was conducted at the Centro de Lançamento de Foguetes Barreira do Inferno, city of Parnamirim, Rio Grande do Norte, in the period February 2011 to January 2012, using pitfall traps, stationary window and beating tray. Among the 26 orders found, the most abundant were: Hymenoptera, Orthoptera, Araneae. Taxa Hymenoptera, Blattodea and Orthoptera showed higher biomass volume. Climatic factors did not influence the fall of Arthropods in the traps, however, the lowest abundance during the rainy season the action of raindrops, reduced the activity of these arthropods on vegetation, reducing its capture in traps (pitfall traps and stationary window ) and method of collection(entomological umbrella)

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Farming of marine shrimp is growing worldwide and the Litopenaeus vannamei (L. vannamei) shrimp is the species most widely cultivated. Shrimp is an attractive food for its nutritional value and sensory aspects, being essential the maintenance of this attributes throughout storage, which takes place largely under freezing. The aim of this research was to evaluate quality characteristics of Litopenaeus vannamei shrimp, during freezing storage and to verify the effect of rosemary (Rosmarinus officinalis) adding. Considering the reutilization of processing shrimp wastes, total carotenoids analysis were conducted in waste of Litopenaeus vannamei shrimp and in the flour obtained after dryer. Monthly physicochemical and sensorial analysis were carried out on shrimp stored at 28,3 ± 3,8ºC for 180 days. Samples were placed in polyethylene bags and were categorized as whole shrimp (WS), peeled shrimp (PS), and PS with 0,5% dehydrated rosemary (RS). TBARS, pH, total carotenoid and sensorial Quantitative Descriptive Analysis (QDA) were carried out. Carotenoid total analysis was conducted in fresh wastes and processed flour (0 day) and after 60, 120 and 180 days of frozen storage. After 180 days, RS had lower pH (p = 0.001) and TBARS (p = 0.001) values and higher carotenoids (p = 0.003), while WS showed higher carotenoid losses. Sensory analysis showed that WS were firmer although rancid taste and smell were perceived with greater intensity (p = 0.001). Rancid taste was detected in RS only at 120 days at significantly lower intensity (p = 0.001) than WS and PS. Fresh wastes had 42.74μg/g of total carotenoids and processed flour 98.51μg/g. After 180 days of frozen storage, total carotenoids were significantly lower than 0 day (p<0,05). The addition of rosemary can improve sensory quality of frozen shrimp and reduce nutritional losses during storage. Shrimp wastes and flour of L. vannamei shrimp showed considerable astaxanthin content however, during storage it was observed losses in this pigment

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The aim of this experiment was to evaluate the hypothesis that the M. amazonicum prawns accept feeding in trays. Six ponds were stocked with 10 juveniles II (1.2 +/- 0.7 g) per m(2) in 02/14/2003. An entirely randomized experimental design with 2 treatments (feeding in trays or feeding to the throw) and 3 replicates was used. Prawn average weight, survival, productivity, and physical and chemical variables of the water were compared between treatments using "t" test of Student. Average weight, survival and productivity were, respectively, 7.2 +/- 0.3 g, 46.8 +/- 7.8% and 335 +/- 45 kg/ha in feeding tray treatment and 6.8 +/- 0.1 g, 85.8 +/- 5.2% and 586 +/- 42 kg/ha in feed to the throw treatment. Survival and productivity differed significantly (p<0.5), while that average weight didn't differ significantly. M. amazonicum needs to use further number of trays per area, possibly due to territorial and aggressive behavior.

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The benznidazole (BNZ) is the only alternative for Chagas disease treatment in Brazil. This drug has low solubility, which restricts its dissolution rate. Thus, the present work aimed to study the BNZ interactions in binary systems with beta cyclodextrin (β-CD) and hydroxypropyl-beta cyclodextrin (HP-β-CD), in order to increase the apparent aqueous solubility of drug. The influence of seven hydrophilic polymers, triethanolamine (TEA) and 1-methyl-2- pyrrolidone (NMP) in benznidazole apparent aqueous solubility, as well as the formation of inclusion complexes was also investigated. The interactions in solution were predicted and investigated using phase solubility diagram methodology, nuclear magnetic resonance of protons (RMN) and molecular modeling. Complexes were obtained in solid phase by spray drying and physicochemical characterization included the UV-Vis spectrophotometric spectroscopy in the infrared region, scanning electron microscopy, X-ray diffraction and dissolution drug test from the different systems. The increment on apparent aqueous solubility of drug was achieved with a linear type (AL) in presence of both cyclodextrins at different pH values. The hydrophilic polymers and 1-methyl-2-pyrrolidone contributes to the formation of inclusion complexes, while the triethanolamine decreased the complex stability constant (Kc). The log-linear model applied for solubility diagrams revealed that both triethanolamine and 1-methyl-2-pyrrolidone showed an action cosolvent (both solvents) and complexing (1-methyl-2-pyrrolidone). The best results were obtained with complexes involving 1-methyl-2-pyrrolidone and hydroxypropylbeta- cyclodextrin, with an increased of benznidazole solubility in 27.9 and 9.4 times, respectively. The complexes effectiveness was proven by dissolution tests, in which the ternary complexes and physical mixtures involving 1-methyl- 2-pyrrolidone and both cyclodextrins investigated showed better results, showing the potential use as novel pharmaceutical ingredient, that leads to increased benznidazole bioavailability

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O presente trabalho teve como objetivo avaliar a influência da temperatura e do substrato na germinação, bem como determinar a profundidade ideal de semeadura para emergência de plântulas de Oenocarpus minor Mart. Utilizou-se o delineamento experimental inteiramente casualizado, em esquema fatorial 3x4 (temperatura x substrato), com três repetições de 30 sementes cada. As sementes foram colocadas no interior de caixas plásticas contendo substrato umedecido com água destilada e mantidas em câmaras de germinação à temperatura constante e com fotoperíodo de 12 horas. Para a emergência, foram usadas 4 repetições de 24 sementes, distribuídas em bandeja plásticas, com plantmax e vermiculita, em 0; 2 e 4 cm de profundidade de semeadura, mantidas em casa de vegetação. Baseado nos resultados obtidos, os substratos mais adequados para a germinação de sementes foram a areia e a vermiculita, e a melhor temperatura foi a de 30ºC. Profundidade superior a 2 cm é inadequada para a semeadura de Oenocarpus minor Mart.

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This thesis aimed to assess the increase in solubility of simvastatin (SINV) with solid dispersions using techniques such as kneading (MA), co-solvent evaporation (ES), melting carrier (FC) and spray dryer (SD). Soluplus (SOL), PEG 6000 (PEG), PVP K-30 (PVP) e sodium lauryl sulphate (LSS) were used as carriers. The solid dispersions containing PEG [PEG-2(SD)], Soluplus [SOL-2(MA)] and sodium lauryl sulphate [LSS-2(ES)] were presented with a greater increase in solubility (5.02, 5.60 and 5.43 times respectively); analyses by ANOVA between the three groups did not present significant difference (p<0.05). In the phase solubility study, the calculation of the Gibbs free energy (ΔG) revealed that the spontaneity of solubilisation of SINV occurred in the order SOL>PEG >PVP 75%>LSS, always 80%. The phase diagrams of PEG and LSS presented solubilization stoichiometry of type 1:1 (type AL). The diagrams with PVP and SOL tend to 1:2 stoichiometry (type AL + AP). The stability coefficients (Ks) of the phase diagrams revealed that the most stable reactions occurred with LSS and PVP. The solid dispersions were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), particle size distribution (PSD), near-infrared spectroscopy imaging (NIR-CI) and X-ray diffraction of the powder using the Topas software (PDRX-TOPAS). The solid dispersion PEG-2(SD) presented the greatest homogeneity and the lowest degree of crystallinity (18.2%). The accelerated stability study revealed that the solid dispersions are less stable than SINV, with PEG-2(SD) being the least stable, confirmed by FTIR and DSC. The analyses by PDRX-TOPAS revealed the amorphous character of the dispersions and the mechanism of increasing solubility

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The present work concerns an auto-ethnographic study based on life experiences and reflections of an educator at Escola Viva Preschool and Elementary-Middle School, located in the city center of Natal, Rio Grande do Norte. As a cognitive model of operation, we use the metaphor of the Circle Dance. The objective of this study is to identify, interpret and describe the ludopoetics that are achieved through a Musical Education program, which we denominate, Humanescent. The data of this investigation was derived from the music making by Preschool and Elementary-Middle School students at Escola Viva during 2007, 2008 and 2009, from which 20 learners were selected to form the corpus, along with the description and interpretation of photos of their experiences and sand tray scenes. We justify the methodological systemization of the research based on our own pedagogical practice, which supports Musical Education in the schools based on the principals of Embodiment, Autopoesis and Flow. The methodological systemization was developed through an Action Research model and on the concepts of Systemic Development, with the goal of re-reading the context investigated through the structuring of categories of Ludopoesis: Self-esteem, Self-territory, Self-connectivity, Self-realization and Selfworth. We used an observant-participant research approach with regard to the perception of emergent knowledge, the surroundings, the experience lived and the contextual and vibration of the circumstances. Besides this, we used projection to interpret the experiences lived, in the form of drawings, short poems, letters or sand tray scenes as symbolic interpretations of experience. In the unfolding of the Ludopoetic Process (Selfesteem, Self-territory, Self-connectivity, Self-realization and Selfworth) we draw conclusions about the relevance of the ludic musical experience, which foments the formation of the self based on music learning, and which is demonstrated in the Embodiment of the learners. In the auto-formative process (of learners and educators) we observe the importance of pedagogical work based on Musical Humanescent Education that gives value to the music making path to the construction of music and performance in play, creativity, and sensibility. The experience of making music in a playful way allows for organization of the self and its autonomous production in the joy of living within a ludopoetic process. These findings highlight the educator as in a permanent state of selfformation, which generates moments of flow. However, in Musical Humanescent Education, music is learned collectively, doing a circle dance, experiencing love, fostering an expansion of the creative spirit, and giving recognition to playfulness as a necessary condition for education and to the value of music made with the true nature and sensibilities of the educators

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A descriptive, quantitative approach and non-participant observation study, which was aimed at analyzing the association between knowledge and practice of inclusion and maintenance of urinary catheter by nursing professionals in the occurrence of urinary tract infection, performed in the ICU of Onofre Lopes University Hospital in Natal / RN. The original sample was composed of 42 nursing staff professional, five (5) nurses and 37 nursing technicians, 27 of them were outsourced (FUNPEC and IEL fellows) and 10 servers UFRN. Data collection was performed using two instruments, the first observation procedures used in the insertion and manipulation of indwelling urinary catheter (IUC) and the second with a questionnaire that addressed the characterization data of respondents, knowledge and conduct the insertion and manipulation of the IUC. The results were tabulated in Microsoft Excel and analyzed using SPSS software, version 15.0. We found the prevalence of institutional staff members on outsourcing - IEL and FUNPEC - (64.3%) were female (69.0%), aged 21 to 35 years (59.5%) and with mid-level education (88.1%). As to knowledge, we found that the nurses had levels of good to excellent and the nursing technicians, to regulate the poor. The nurses made a mistake when choosing IUC (40.0%) and washing hands (30.0%) and technicians on hand washing (74.4%) and the contents of the tray (34.7%). In relation to the conduct of insertion of IUC, the nurses made a mistake when choosing SVD (66.7%) and washing hands (57.1%). Regarding the handling of IUC/drainage system, the technicians were wrong more about washing their hands (56.0%). Analyzing the misconduct to the categorization of knowledge, we saw that the nursing staff who had missed more had inadequate knowledge (ρ = 0.001). At the end we found the risk of a patient to acquire UTI is higher in two and a half times when there is a large number of mismatches, patient spends more time using the IUC and hospitalized in the ICU. As regards the study hypotheses, we accept the alternative hypothesis and reject the null hypothesis proposed at the start of this research, where the number of gaps in knowledge and behavior increases the incidence of urinary tract infection.

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Objetivou-se adequar a metodologia do teste de envelhecimento acelerado para avaliação do potencial fisiológico de sementes de quatro lotes dos genótipos de alface 'Babá de verão', 'Tainá' e 'Vera', aplicando-se o método tradicional e com o uso de solução saturada de NaCl. Para tal, as sementes foram submetidas à determinação do teor de água, testes de germinação e vigor (primeira contagem, condutividade elétrica, emergência em bandeja, índice de velocidade de emergência) incluindo o teste de envelhecimento acelerado, conduzido nos períodos de 24, 48, e 72 horas, a 41°C com e sem solução saturada de NaCl. O experimento foi conduzido em delineamento inteiramente casualizado com quatro repetições. Os procedimentos tradicional e com o uso da solução saturada de NaCl por 72 horas foram sensíveis em estratificar os lotes em níveis de vigor, além de estarem de acordo com os demais testes utilizados. Portanto, o envelhecimento acelerado de sementes de alface deve ser feito utilizando o período de 72 horas, podendo ser realizado tanto pelo método tradicional quanto pelo método da solução saturada de NaCl.

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A técnica para a determinação da viabilidade de sementes de amendoim por meio do tetrazólio (TZ) é, atualmente, aquela pela qual as sementes, após embebição em água, têm o tegumento removido. A seguir as sementes são, em grupo, imersas na solução de TZ. Essa técnica dificulta o contato entre os tecidos das faces internas dos cotilédones e a solução de TZ em virtude de que o período prévio de embebição em água não é suficiente para que os cotilédones das sementes de amendoim se separem. Assim, o acesso da solução de TZ aos tecidos das faces internas dos cotilédones e ao próprio eixo embrionário, que fica entre as duas faces cotiledonares internas, é consideravelmente dificultado. Na suposição de que este procedimento levaria a resultados de testes de TZ que se correlacionam mal com o desempenho germinativo das sementes no campo, tentou-se uma nova técnica pela qual as sementes, após a embebição em água, além de terem o tegumento removido, são manualmente separadas em seus cotilédones, com o eixo embrionário ligado a um deles, e os cotilédones de uma determinada semente, agora separados, imersos na solução de TZ contida em uma célula individual de uma bandeja de PVC. A hipótese aqui formulada mostrou-se correta : a técnica alternativa de submissão das sementes de amendoim à solução de tetrazólio permitiu a obtenção de resultados que, comparados com os da técnica convencional, refletiram de modo mais preciso o desempenho germinativo das sementes no campo.