59 resultados para Interacção temperatura - radiação solar


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The purpose of this research is to analyze different daylighting systems in schools in the city of Natal/RN. Although with the abundantly daylight available locally, there are a scarce and diffuse architectural recommendations relating sky conditions, dimensions of daylight systems, shading, fraction of sky visibility, required illuminance, glare, period of occupation and depth of the lit area. This research explores different selected apertures systems to explore the potential of natural light for each system. The method has divided into three phases: The first phase is the modeling which involves the construction of three-dimensional model of a classroom in Sketchup software 2014, which is featured in follow recommendations presented in the literature to obtain a good quality of environmental comfort in school settings. The second phase is the dynamic performance computer simulation of the light through the Daysim software. The input data are the climate file of 2009 the city of Natal / RN, the classroom volumetry in 3ds format with the assignment of optical properties of each surface, the sensor mapping file and the user load file . The results produced in the simulation are organized in a spreadsheet prepared by Carvalho (2014) to determine the occurrence of useful daylight illuminance (UDI) in the range of 300 to 3000lux and build graphics illuminance curves and contours of UDI to identify the uniformity of distribution light, the need of the minimum level of illuminance and the occurrence of glare.

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This research is presented as a comparative study about the baking capacity of two box type ovens, produced from a packing case used to equipment transportation. The two ovens have different internal settings, with the greenhouse effect and the concentration of incident solar radiation as the main parameters of differentiation. The main features of the ovens are the low cost, the reuse of materials, the manufacturing and assembly processes simplified, the easy management and the ability of baking a variety of foods simultaneously. The manufacturing and operation of the ovens can be handled by any social and intellectual level of people. The feasibility of the ovens to bake the tested foods was proved with success, ensuring the supremacy of the mirrored oven. The results obtained for both ovens were competitive even with the conventional gas oven, producing the baking of three cakes with 750g in just 80 minutes.

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The variability / climate change has generated great concern worldwide, is one of the major issues as global warming, which can is affecting the availability of water resources in irrigated perimeters. In the semiarid region of Northeastern Brazil it is known that there is a predominance of drought, but it is not enough known about trends in climate series of joint water loss by evaporation and transpiration (evapotranspiration). Therefore, this study aimed to analyze whether there is increase and / or decrease evidence in the regime of reference evapotranspiration (ETo), for the monthly, annual and interdecadal scales in irrigated polo towns of Juazeiro, BA (9 ° 24'S, 40 ° 26'W and 375,5m) and Petrolina, PE (09 ° 09'S, 40 ° 22'W and 376m), which is the main analysis objective. The daily meteorological data were provided by EMBRAPA Semiárido for the period from 01.01.1976 to 31.12.2014, estimated the daily ETo using the standard method of Penman-Monteith (EToPM) parameterized by Smith (1991). Other methods of more simplified estimatives were calculated and compared to EToPM, as the ones following: Solar Radiation (EToRS), Linacre (EToL), Hargreaves and Samani (EToHS) and the method of Class A pan (EToTCA). The main statistical analysis were non-parametric tests of homogeneity (Run), trend (Mann-kendall), magnitude of the trend (Sen) and early trend detection (Mann-Whitney). The statistical significance adopted was 5 and / or 1%. The Analysis of Variance - ANOVA was used to detect if there is a significant difference in mean interdecadal mean. For comparison between the methods of ETo, it were used the correlation test (r), the Student t test and Tukey levels of 5% significance. Finally, statistics Willmott et al. (1985) statistics was used to evaluate the concordance index and performance of simplified methods compared to the standard method. It obtained as main results that there was a decrease in the time series of EToPM in irrigated areas of Juazeiro, BA and Petrolina, PE, significant respectively at 1 and 5%, with an annual magnitude of -14.5 mm (Juazeiro) and -7.7 mm (Petrolina) and early trend in 1996. The methods which had better for better agreement with EToPM were EToRS with very good performance, in both locations, followed by the method of EToL with good performance (Juazeiro) and median (Petrolina). EToHS had the worst performance (bad) for both locations. It is suggested that this decrease of EToPM can be associated with the increase in irrigated agricultural areas and the construction of Sobradinho lake upstream of the perimeters.

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Melanocytic nevi (MNs) are benign melanocytic proliferations of cells, which can be found in the skin and mucous coat, including the oral mucosa. However, skin NMs are more common when compared to those that affect the oral mucosa. The molecular mechanisms involved in the development of nevi and the factors that can influence the migration pattern of the nevus cells are little explored. The aim of this study was to analyze the immunohistochemical expression of E-cadherin protein and Bcl-2 in oral / skin NMs and relate them to the clinical characteristics (gender, age, location, exposure to solar radiation) and histopathological types. 36 cases of oral NMs and 34 Skin NMs were analyzed. The immunohistochemistry was used of the protein E-cadherin and bcl-2, which were analyzed the intensity (weak, moderate and strong) and distribution marking (diffuse and focal). The immunoreactivity also analyzed as to the types of nevus cells (epithelioid cells -A, -B lymphocyte and fibroblast-like -C). Statistical analysis was performed using the chi-square tests of Pearson and Spearman correlation with significance level set at 5%. Of the 70 cases of NMs, 82.9% were female, 48.6% aged 26-50 years, 51.4% were diagnosed histologically as intradermal / intramucosal nevi and 80% were NMs acquired. Immunohistochemical expression of BCL2 and E-cadherin were variables in the sample and showed no association with clinical parameters. The expression of bcl-2 and E-cadherin were variable according to the types of nevus cells (A, B and C) (P = 0.001). The expression of bcl-2 was more diffuse in congenital MNs (p = 0.002). E-cadherin was positive in 83.3% of MNs <1cm (p = 0.001) and exhibited weak staining in 73.9% of MNs that were in exposed areas (p = 0.010). Based on these results, it is suggested that the E-cadherin has a modulating effect on the migratory properties of NMs, and bcl-2 is a marker of MNs with increased proliferative capacity.

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Building design is an effective way to achieve HVAC energy consumption reduction. However, this potentiality is often neglected by architects due to the lack of references to support design decisions. This works intends to propose architectural design guidelines for energy efficiency and thermal performance of Campus/UFRN buildings. These guidelines are based on computer simulations results using the software DesignBuilder. The definition of simulation models has begun with envelope variables, partially done after a field study of thirteen buildings at UFRN/Campus. This field study indicated some basic envelope patterns that were applied in simulation models. Occupation variables were identified with temperature and energy consumption monitoring procedures and a verification of illumination and equipment power, both developed at the Campus/UFRN administration building. Three simulation models were proposed according to different design phases and decisions. The first model represents early design decisions, simulating the combination of different types of geometry with three levels of envelope thermal performance. The second model, still as a part of early design phase, analyses thermal changes between circulation halls lateral and central and office rooms, as well as the heat fluxes and monthly temperatures in each circulation hall. The third model analyses the influence of middle-design and detail design decisions on energy consumption and thermal performance. In this model, different solutions of roofs, shading devices, walls and external colors were simulated. The results of all simulation models suggest a high influence of thermal loads due to the incidence of solar radiation on windows and surfaces, which highlights the importance of window shading devices, office room orientation and absorptance of roof and walls surfaces

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The employment of flexibility in the design of façades makes them adaptable to adverse weather conditions, resulting in both minimization of environmental discomfort and improvement of energy efficiency. The present study highlights the potential of flexible façades as a resource to reduce rigidity and form repetition, which are usually employed in condominiums of standardized houses; as such, the work presented herein contributes to field of study of architectural projects strategies for adapting and integrating buildings within the local climate context. Two façade options were designed using as reference the bionics and the kinetics, as well as their applications to architectural constructions. This resulted in two lightweight and dynamic structures, which cater to constraints of comfort through combinations of movements, which control the impact of solar radiation and of cooling in the environment. The efficacy and technical functionality of the façades were tested with comfort analysis and graphic computation software, as well as with physical models. Thus, the current research contributes to the improvement of architectural solutions aimed at using passive energy strategies in order to offer both better quality for the users and for the sustainability of the planet

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Although already to exist alternative technique and economically viable for destination of used tires, quantitative data on properties of constructive elements that use the rubber waste as aggregate still are restricted. In the present work, the waste proceeding from industry of retreading as material for manufacture of composite destined to the production of constructive elements was considered. Mechanical and thermal properties of mortar had been analyzed Portland cement with addition of waste without treatment, in the ratios of 10%, 20% and 30% in mass in relation to the mass of the cement, substituting the aggregate in the trace in mortar 1:5 mass cement and sand. The size of the used residue varied between 0,30mm and 4,8mm (passing in the bolter 4,8mm and being restrained in the one of 0,30mm), being it in the formats fibers and granular. The influences of the size and the percentage of residue added to the mortar (in substitution to the aggregate) in the thermal and mechanical properties had been considered. Assays of body-of-test in thestates had been become fullfilled cool (consistency index) and hardened (absorption of water for capillarity, strength the compression, traction and strength flexural). The work is centralized in the problem of the relation thermal performance /strength mechanics of used constructive systems in regions of low latitudes (Been of the Piauí), characterized for raised indices of solar radiation.

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An alternative box-type solar oven constructed from the scrap iron of a gas conventional cook is presented, which functions principles are the effect greenhouse and the concentration. The oven of the conventional cook is the baking enclosure where the absorber (pot) of the solar oven is located, being re-covered for a glass blade for the generation of the greenhouse effect isolated lateral and having deep its and for a composite the plaster base and EPS. Segments of plain mirrors had been placed in the laterals of the oven for the concentration of the radiation and a reflecting parabola was introduced in the baking enclosure for the exploitation of the incident reflected radiation in the interior of the oven. The oven is mobile to allow one better aiming of exactly in relation to the apparent movement of the sun. The thermal economic and of materials viabilities of the stove in study will be demonstrate The average internal temperature of the absorber was around 150°C and the internal temperature around 120°C. Will demonstrate that its low cost and good thermal performance represents basic characteristics for the viability of large use of such archetype, mainly for cooking the decreases and averages temperatures. One will reveal that the archetype in study is competitive with the box-type solar cooker conceived in the whole world

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Experiments were performed to study the effect of surface properties of a vertical channel heated by a source of thermal radiation to induce air flow through convection. Two channels (solar chimney prototype) were built with glass plates, forming a structure of truncated pyramidal geometry. We considered two surface finishes: transparent and opaque. Each stack was mounted on a base of thermal energy absorber with a central opening for passage of air, and subjected to heating by a radiant source comprises a bank of incandescent bulbs and were performed field tests. Thermocouples were fixed on the bases and on the walls of chimneys and then connected to a data acquisition system in computer. The air flow within the chimney, the speed and temperature were measured using a hot wire anemometer. Five experiments were performed for each stack in which convective flows were recorded with values ranging from 17 m³ / h and 22 m³ / h and air flow velocities ranging from 0.38 m / s and 0.56 m / s for the laboratory tests and air velocities between 0.6 m/s and 1.1m/s and convective airflows between 650 m³/h and 1150 m³/h for the field tests. The test data were compared to those obtained by semi-empirical equations, which are valid for air flow induced into channels and simulated data from 1st Thermodynamics equation. It was found that the chimney with transparent walls induced more intense convective flows than the chimney with matte finish. Based on the results obtained can be proposed for the implementation of prototype to exhaust fumes, mists, gases, vapors, mists and dusts in industrial environments, to help promote ventilation and air renewal in built environments and for drying materials, fruits and seeds

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This work aims to study the drying of cashew-nut pulp with different lay-out of dryers using conventional and solar energy. It concerns with the use of exceeding of the regional raw material and the suitable knowledge for the applicability of the drying systems as pathway for food conservation. Besides, it used renewable sources as solar energy to dry these agroindustrial products. Runs were carried out using a conventional tray-dryer with temperature, air velocity control and cashew slice thickness of 55°C, 65°C, 75°C; 3.0; 4.5, 6.0 m s-1; 1.0; 1.5 and 2.0 cm, respectively, in order to compare the studied systems. To evaluate the conventional tray-dryer, it was used a diffusional model of 2nd Fick´s law, where the drying curves were quite well fitted to an infinite flat plate design. For the drying runs where the room temperature had no control, it was developed a phenomenological-mathematical model for the solar dryer with indirect radiation under natural and forced convection based on material and energy balances of the system. Besides, it was carried out assays in the in natura as well as dehydrated, statistic analysis of the experimental drying data, sensorial analysis of the final dry product and a simplified economical analysis of the systems studied

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This work study of solar distillation feasibility in effluent of petroleum industry: produced water, making possible your reuse for irrigation of oleaginous cultures or fodder crops or in steam generation, as well the transport phenomena involved. The methodology for development of this project was to characterize the effluent to be treated and to accomplish physical and chemical analysis in the distilled, to build distillation equipment, concomitant operation of both equipments and implementation of data processing and economical evaluation. The methodology used for all parameters is outlined in APHA (1998) and sampling of the type compound. The feeding of distillation equipment was performed with treated effluent from UTPF of Guamaré. The temperature was monitored throughout the distillers and during the time of operation. The distillers feed occur, as a rule, for sifon. The distillers were operated by a period of 17 months between July 2007 and February 2009, in which 40 experiments were performed. The radiation and temperature datas were acquired in the INPE s site and the temperature inside of the distillers was registered by DATALOGGER Novus. The rates of condensation (mL / min) were determined by measuring of the flow in a graduate test tube of 10 mL and a chronometer. We used two simple solar effect distillers of passive type with different angles in coverage: 20 ° and 45 °. The results obtained in this study and the relevant discussions are divided into six topics: sample characterization and quality of distilled; construction of distillers; operation (data, temperature profile), climatic aspects, treatment of data and economical analysis. Results obtained can be inferred that: the energy loss by the adoption of vessel glass was not significant, however, complicates the logistics of maintenance the equipment on a large scale. In the other hand, the surface of the tub with a glass shield on the equipment deterioration, both devices showed similar performance, so there is not justified for use of equipment 450. With regard to the climatological study it was verified that the Natal city presents monthly medium radiation varying in a range between 350 and 600 W/m2, and medium of wind speed of 5 m / s. The medium humidity is around 70% and rainfall is very small. The regime of the system is transient and although it has been treated as a stationary system shows that the model accurately represents the distillers system's 20 degrees. The quality of the distilled with regard to the parameters evaluated in this study is consistent with the Class 3 waters of CONAMA (Resolution 357). Therefore we can conclude that solar distillation has viability for treat oilfield produced water when considered the technical and environmental aspects, although it is not economically viable

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This work main objective is to study the use of bricks in barium X-rays rooms in order to contribute to the optimization of shielding rooms diagnosis. The work was based on experimental measurements of X-ray attenuation (40 to 150 kV), using ceramic seal bearing the incorporation of barium sulfat (BaSO4). Different formulations were studied in three different firing temperatures and evaluated for incorporation in the ceramic body. The composition of 20% of barite processed at a temperature of 950 ° C showed better physical and mechanical properties, is considered the most suitable for the purpose of this work. Were produced bricks sealing composition formulated based on that presented the best technological features. These blocks were tested physically as a building material and wall protective barrier. Properties such as visual, deviation from the square, face flatness, water absorption and compressive strength were evaluated for all the blocks produced. The behavior of this material as attenuator for X-rays was investigated by experimental results which take into account mortar manufacturers barium through the different strains and compared with the reference material (Pb). The simulation results indicated that the ceramic block barium shows excellent properties of attenuation equivalence lead taking into account the energy used in diagnostic X-ray

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An cylinder-parabolic solar concentrator is presented to produce steam for different applications. This prototype was built in glass fiber with dimensions that follow a study of optimization of parameters inherent in the optical reflection of sunlight by the surface of reflection and absorption of the same by tubing that leads the fluid of work. The surface of the concentrator of 2.24 m² has been covered by layers of mirror with 1.0 m of lenght and 2.0 cm wide. The absorb tubing consists of a copper tube diameter equal to 28 mm. The concentrator is moving to follow the apparent motion of the sun. It will be presented the processes of manufacturing and assembly of the concentrator proposed, which has as main characteristics the facilities construction and assembly, in addition to reduced cost. Will be presented data from tests performed to produce steam setting up some parameters that diagnose the efficiency of the concentrator. It will be demonstrated the viabilities thermal, economic and of materials of the proposed system.The maximum temperature achieved in the vacuum tube absorber was 232.1°C and average temperature for 1 hour interval was 171.5°C, obtained in a test with automation. The maximum temperature achieved in the output of water was 197.7°C for a temperature of 200.0°C in the absorber tube. The best average result of the water exit temperature to interval of 1 hour was 170.2°C for a temperature of 171.2°C, in the absorber tube, obtained in test with automation. Water exit mean temperatures were always above of the water steaming temperature. The concentrator present a useful efficiency of 38% and a production cost of approximately R$ 450,00 ( $ 160.34)

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There were studied the variation of the solar ultraviolet radiation (UVR) in four wavelengths (305 nm, 320 nm, 340 nm e 380 nm) and erythemic dose, measured in Natal RN Brazil, from January 2001 until December 2007, using the ground ultraviolet radiometer of the Instituto Nacional de Pesquisas Espaciais / Centro Regional do Nordeste INPE-CRN, fixed on the roof of the Laboratório de Variáveis Ambientais Tropiciais LAVAT-INPE-CRN. It was verified that the mean value of the UVR in the city reachs the HIGH index before 09h00 a.m. and VERY HIGH before 09h40 a.m.; it was also verified that, except in the months of June and July, in the other months of the year the UVR reachs the HIGH index before 10h00 a.m., despite of the recommendations broadcasting in the media about the safe time to people stay ashore on the beaches of the city. After 14h30 p.m., the UVR reachs the MODERATE index in any month of the year. These evidence are valid to all years of the period studied, i.e., 2001 to 2007. The year of 2004 presented the lower mean values of UVR indices, and the year of 2007 presented the higher mean values of UVR index. It was prove, by means of the analysis of variance (ANOVA), the variation in the four wavelengths and in the erythemic dose. Considering that the city has high indices of skin cancer and cataract, the results of the research may be use as a data source to studies that intend to support programs of public health. At the same time, the results of the research may be applied to material science and agriculture studies

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It s presented a solar collector to be used in a system for heating bath water, whose main characteristic is its low cost. The collector consists of five plates of PVC with 10 mm thick, 200 mm in width and 1400mm in length, with an area equal to 1.4 square meters. The plates were connected in parallel to the ends of PVC tubes of  40 mm and 32 mm. The plates were coated on one side with aluminum sheets of soft drinks and beers cans open. The system worked on a thermosiphon and was tested in two configurations: the plates uncoated and coated with aluminum material, to determine the influence of material on the efficiency of the collector. For both configurations was used EPS plates below the surface to minimize heat losses from the botton. The thermal reservoir of the heating system is, also, alternative and low cost, since it was constructed from a polyethylene tank for storing water, with volume of 150 end 200 liters. It will be presented the thermal efficiency, heat loss, water temperature of the thermal reservoir at the end of the process and simulation of baths for a house with four residents. The will be demonstrated thermal, economic and material viability of the proposed collector, whose main innovation is the use of recyclables materials, cans of beer and soft drinks, to increase the temperature of the absorber plate.