1,348 research outputs found
Compost-bedded pack barns in the state of Minas Gerais: architectural and technological characterization
ArticleCompost bedding pack (CBP) barns have been receiving increased attention as an
alternative housing system for dairy cattle. Thus, a systematic investigation of the primary
management practices of dairy cattle in CBP barns in the state of Minas Gerais (Brazil) has proven
to be of environmental and economic relevance. The aim of this research was to summarize the
compost bed data, barn dimension data and to determine the major interactive factors in the
success of bed composting from qualitative and quantitative methods. Data for this study was
collected from 16 CBP barns, distributed throughout the southern state of Minas Gerais (Brazil)
between March 2017 and July 2018. These data were used to describe the building layouts and
dimensions, to identify barn management practices, and to characterize the compost bedding
material concerning moisture content. The majority of these barns had feed alleys and driveways;
overshot ridges with frequent orientation from NE to SW; bedding process and aeration using
mechanical tillage. The average bedding moisture content was found to be 36.9 ± 5.2% (w.b.).
Based on the information found, it is possible to evaluate that there is still no defined construction
pattern, with a high variation of size and technologies employed
Uso De água Residuária Da Piscicultura No Cultivo De Alface
Lettuce stands out as the main leafy vegetable consumed in Brazil, with divergence regarding adaptability to different environmental conditions, which include salinity. The objective of the work was to evaluate the response of lettuce cultivars to the use of saline wastewater from fish farming. The experiment was conducted in a completely randomized design with four replicates, in a factorial 7 × 4, corresponding to seven cultivars (Regiane, Vera, Isabela, Elisa, Amelia, Lavinia and Angelina) and four salt concentrations (1.2, 2.2, 3.2 and 4.2 dS m-1). The evaluated characteristics were: number of leaves, leaf area, crown diameter and shoot fresh and dry matter. Diluted wastewater from fish farming can be used in the preparation of solution for fertigation of lettuce. The cultivars Regiane and Elisa had higher production of leaves and leaf area, while Amélia and Angelina were the most productive in terms of biomass. The cultivars Vera, Isabela, Amélia and Angelina were more tolerant to the salinity of the fertigation solution. © 2016, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.20872873
Analysis of environmental conditions in two different Compost Bedded Pack Barn systems for dairy cattle
Received: February 1st, 2023 ; Accepted: April 27th, 2023 ; Published: May 10th, 2023 ; Correspondence: [email protected], [email protected] objective of this study was to analyse and compare the thermal environment of
dairy cattle facilities in an open compost bedded pack barn (CBP) with natural ventilation and
closed CBP (without thermal insulation) and climate control system. The research was conducted
in a property located in Zona da Mata, Minas Gerais, Brazil. During the summer and for different
periods of the day, the following average environmental variables observed inside the facilities
were measured: dry bulb temperature, relative humidity and Temperature and Humidity Index
(THI). The results were submitted to an analysis of variance to determine the significance of the
variables in the different treatments. It was found that the closed and climate control system CBP
promoted greater control of the facility's internal microclimate, registering smaller thermal
amplitudes and a greater reduction in the animals' exposure time to stressful thermal conditions,
compared to the CBP with natural ventilation. However, during summer afternoons, comfort
indices indicated moderate stress. It is concluded that the closed CBP, regarding the analysed
variables, indicated potential use, provided that a careful study of the climate of the region is
carried out before implementation, the factors related to the ambient conditioning and better
insulation of the construction are adjusted. The climatic variables inside the open CBP indicated
a high stress condition for the animals, suggesting the placement of positive pressure fans and
sprinklers properly distributed in the feed alley, to guarantee benefits to the entire area of the
animal housing
Assessment of a low-cost solar water heating systems in farrowing facilities
ArticleThe objective of this study was to develop a prototype solar heater using alternative materials and then to compare its thermal efficiency against that of two other commercial solar heating systems when heating the floor of piglet housing. To evaluate the thermal heaters, temperature sensors were installed in the inlet and outlet of each floor and the thermal reservoir. The results showed good performance, however the thermal efficiency of the alternative heater was lower than the conventional systems. However, due to the construction of this solar collector with alternative materials its cost was relatively low and its operation is easier than the other conventional heater, therefore this heater is a good alternative to use for small livestock producer
Study for pediatric protocol optimization in chest CT scan
Radiological exams are increasingly used in clinic for diagnostic analysis of different types of pathologies. These exams are associated with a dose that is received by the patient. In addition, the risks in exposure to ionizing radiation are different according to the group which the individual belongs. According to age, the group of children is more radiosensitive than adults. In this work we have obtained values of the air-weighted kerma index for chest scans studies in a General Electric Computed Tomography (CT) scanner model Discovery with 64-channels. Using an adult protocol, two scans have been performed, one using a cylinder standard PMMA phantom while the second one has used an oblong chest phantom designed for a two year old pediatric patient. Furthermore, other protocols have been selected with a constant voltage but changing the X-ray tube current and maintaining the image quality in order to obtain a reduction in the received dose by the pediatric patient. The use of the adult protocol in the child phantom has an air-weighted kerma index of 89.5% greater than the kerma index using the adult phantom. Due small patients receive higher doses; the use of specific protocols for children is important for the dose reduction in CT tests. An optimized pediatric chest protocol is presented, obtaining as a result dose reduction compared with the adult protocol of 62.2%. Because of different CT scanners characteristics and in order to optimize protocols regard to dose and diagnostic image quality, it is necessary to use pediatric phantoms in health centers
Spatial distribution of thermal variables, acoustics and lighting in compost dairy barn with climate control system
ArticleThe main objective of this research was to evaluate the spatial distribution of the
thermal variables, acoustics and lighting in climate controlled compost dairy barn. The
experiment was conducted in October 2017, in a farm located in the west of Minas Gerais state,
Brazil. For the study, the interior of the animal facility was divided into 120 meshes equidistant
points, in which air temperature (tdb), relative humidity (RH), noise, illuminance, and air speed
(Vair) were manually collected. The technique of geostatistics was used to evaluate the distribution
and spatial dependence of variables. Spatial distribution maps showed the occurrence of high
variability of attributes and content within the animal facility. Thermal environment variables
showed alert situations throughout practically the entire facility. The noise and luminance levels
were within the recommended values
Anomalous diffusion on crumpled wires in two dimensions
It is investigated the statistical properties of random walks evolving on
real configurations of a crumpled wire rigidly jammed in two dimensions. These
crumpled hierarchical structures with complex topology are obtained from a
metallic wire injected at a constant rate into a transparent planar cell of
20cm of diameter. The observed diffusion is anomalous with an exponent very
close to that obtained at the threshold of two dimensional percolation. A
comparison of the system studied in this paper with other systems of physical
interest is also made, and an experimental consequence of our results is
discussed.Comment: 10 pages including 4 figures. Physica A (2006). Preprin
Experimental analysis of flameless combustion for reduction of pollutants
Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.This report presents a special form of combustion, called flameless combustion. In contrast to the combustion within stabilized flames, temperature peaks can be avoided at flameless combustion. Critical points of this technology are the realization of thermofluodynamic conditions which stabilize the flameless combustion process and a design to reach flameless conditions. Burners for flameless combustion usually show complex geometries which make simplified schemes difficult and inappropriate. In this case, the present paper proposes a study to determine the viability of a flameless burner design for experimental investigation and a combustion chamber on a laboratorial scale able to use high temperature air to reduce pollutant emissions. During the experiments, it will be used natural gas and preheat air. The influence of the field flow, chamber temperature and preheating air temperature on reaction zone volume was examined using techniques capable of analyzing the temperature field in the combustor. The main conclusions were: a) in contrast to the flames, the combustion had low internal temperature gradients; b) the system has promoted changes in the volume characteristics of combustion significantly reducing pollutants: NOx, CO and UHC (Unburned Hydrocarbons); c) to same conditions no visible flame was observed during the test.dc201
Sensory Evaluation Of Black Instant Coffee Beverage With Some Volatile Compounds Present In Aromatic Oil From Roasted Coffee [análise Sensorial De Bebida Preparada Com Café Instantâneo Com Alguns Compostos Voláteis Presentes No óleo Aromático De Café Torrado]
The oil obtained from Brazilian roasted coffee by supercritical CO2 extraction shows considerable aromatic properties, mainly composed by five aromatic compounds, 2-methylpyrazine; 2-furfurylalcohol, 2,5-dimethylpyrazine; γ-butyrolactone and 2-furfurylacetate. Sensory analyses were used to verify the influence of a mixture of these important classes of aromatic coffee compounds (pyrazines, furans and lactones) and of the roasted coffee aromatic oil on the coffee aroma and flavour of black instant freeze and spray-dried coffee beverages. In the acceptance evaluation of the aroma, the samples prepared with freeze-dried instant coffee without the mixture of volatile compounds (sample 4) were not significantly different from the freeze-dried instant coffee in which the aromatic coffee oil was added (sample 5) and from the sample prepared with freeze-dried coffee in which the mixture of the five volatile was added (sample 3), coincidentally from the same drying process. Therefore, sample (3) did not differ from samples prepared with spray dried instant coffee without (sample 1) and to which (sample 2) the mixture of volatile was added. Therefore, with respect to this attribute, the addition of this mixture did not interfere in this drink acceptance. Taking into consideration the flavor, samples prepared with freeze-dried instant coffee in which the aromatic coffee oil was added (5) and the samples with (3) and without (4) the mixture of the five volatile was added did not differ significantly, however sample (4) did not differ from samples (1) and (2). Regarding this attribute, the addition of the aromatic oil of roasted coffee or a mixture of volatile in samples of freeze-dried instant coffee had a better acceptance than those dried by spray dryer (1) and (2). Thus, the enrichment of drinks with the aromatic oil of roasted coffee, or even with the mixture of the five components did not influence the consumer acceptance with respect to the aroma, but exerts influence with respect to flavour.2917680Sarrazin, C., Representativeness of coffee aroma extracts: A comparision of different extraction methods (2000) Food Chemistry, 70 (1), pp. 99-106Ramos, E., Obtention of brewed coffee aroma extract by optimized supercritical CO2-based process (1998) Journal of Agricultural and Food Chemistry, 46 (10), pp. 4011-4016Oliveira, A.L., Sensory and yield response surface analysis of supercritical CO2 extracted aromatic oil from roasted coffee (2001) Journal of Food Science and Technology, 38 (1), pp. 38-42Nijssen, L.R., (1996) Volatile Compounds in Food, , The Netherlands, TNO-CIVOHolscher, W., Vitzthum, O.G., Steinhart, H., Phenyl alcohol - Source for Odorants in roasted coffee (1992) Journal of Agricultural and Food Chemistry, 40 (4), pp. 655-658Semmelroch, P., Grosch, W., Analysis of roasted coffee powders and brews by gas chromatography-olfactometry of headspace samples (1995) Lebensmittel-Wissenschaft und-Technologie, 28 (4), pp. 310-313Pollien, P., Krebsd, Y., Chaintreau, A., Comparison of a brew and an instant coffee using a new GC-Olfactrometric method (1997), 17. , INTERNATIONAL SCIENTIFIC COLOQUIUM ON COFFEE, Proceedings... Nairobi, Association Scientifique Internationale du CaféMayer, F., Czerny, M., Grosch, W., Sensory study of the character impact aroma compounds of coffee beverage (2000) European Food Research and Technology, 211 (4), pp. 272-276Semmelroch, P., Grosch, W., Studies on character impact odorants of coffee brews (1996) Journal of Agricultural and Food Chemistry, 44 (2), pp. 537-543Maeztu, L., Characterization of espresso coffee aroma by static headspace GC-MS and Sensory flavour profile (2001) Journal of Agricultural and Food Chemistry, 49 (11), pp. 5437-5444Elmore, J.S., Nursten, H.E., The effect of 2-furanmethanethiol upon the flavour of instant coffee (1993) International Journal of Food Science and Technology, 28 (5), pp. 531-536Blank, I., Grosch, W., On the role of (-)-2-methylisoborneol for the aroma of robusta coffee (2002) Journal of Agricultural and Food Chemistry, 50 (16), pp. 4653-4656Bassoli, D.G., Instant coffee with natural aroma by spray-drying (1993), 15, pp. 712-718. , In: INTERNATIONAL SCIENTIFIC COLOQUIUM ON COFFEE, 1993, Proceedings..., Montpellier: Association Scientifique Internationale du CaféCalviño, A.M., Zamora, M.C., Sarchi, M.I., Principal components and cluster analysis for descriptive sensory assessment of instant coffee (1996) Journal of Sensory Studies, 11 (3), pp. 191-210Zamora, M.C., Calvino, A.M., A comparison of methodology applied to the selection of a panel for sensory evaluation of instant coffee (1996) Journal of Sensory Studies, 11 (3), pp. 211-226Jong, S., Heidema, J., van der Knaap, C.M., Generalized procrusters analysis of coffee brands tested by five european sensory panels (1998) Food Quality and Preference, 9 (3), pp. 111-114Oliveira, A.L., Cabral, F.A., Eberlin, M.N., Prediction of solubility of some compounds of roasted coffee aromatic oil in supercritical CO2 (2003), In: INTERNATIONAL SYMPOSIUM ON SUPERCRITICAL FLUIDS, Proceedings..., Versailles: International Society for Advancement of Supercritical FluidsWang, T.H., Shanfield, H., Zlatkis, A., Analysis of trace volatile organic compounds in coffee by headspace concentration and gas chromatography-mass spectrometry (1983) Chromatographia, 17 (8), pp. 411-417Hashim, L., Chaveron, H., Use of methylpyrazine ratios to monitor the coffee roasting (1996) Food Research International, 28 (6), pp. 619-623Roberts, D.D., Pollien, P., Milo, C., Solid-phase microextraction method development for headspace analysis of volatile flavour compounds (2000) Journal of Agricultural and Food Chemistry, 48 (6), pp. 2430-2437Rivetti, D., Effect of water composition and water treatment on expresso coffee percolation (2001), In: INTERNATIONAL SCIENTIFIC COLOQUIUM ON COFFEE, Proceedings... Trieste: Association Scientifique Internationale du CaféMeilgaard, M., Civille, G.V., Carr, B.T., (1987) Sensory Evaluation Techiniques, , Boca Raton: CRC PressStone, H., Sidel, J.L., (1993) Sensory Evaluation Practices, , London: Academic PressSteel, R.G.D., Torrie, J.H., (1980) Principles and Procedures of Statistics - A Biometrical Approach, , Singapura: McGraw-Hil
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