|
|
|
Registros recuperados: 12 | |
|
|
Goneli,André L. D.; Araujo,Willian D.; Hartmann Filho,Cesar P.; Martins,Elton A. S.; Oba,Guilherme C.. |
ABSTRACT: The aim of this study was to adjust mathematical models to the experimental data on the peanut kernels drying in thin layer, as well as to determine the effective diffusion coefficient and the main thermodynamic properties involved in drying of the grains under different air conditions. The peanut kernels, with a water content of 0.59 ± 0.002 (dry basis, d.b.), were dried in a forced air ventilation oven with different temperature levels (40, 50, 60 and 70 °C) until reaching a water content of 0.04 ± 0.001 (d.b.). For the experimental data, eight mathematical models traditionally used to represent the drying kinetics of thin layer of agricultural products were adjusted, also being determined the effective diffusion coefficient and the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Arachis hypogaea L.; Effective diffusivity; Activation energy; Page model; Thermodynamic properties. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000500994 |
| |
|
| |
|
|
Silva,Fernanda P. Da; Siqueira,Valdiney C.; Quinzani,Guilherme A.; Martins,Elton A. S.; Goneli,André L. D.. |
ABSTRACT: The objectives of this study were to describe the process of drying niger seeds through the fitting of different mathematical models to the experimental drying data, to select the best model that represents the phenomenon, and to determine the diffusion coefficients and thermodynamic properties of the product. Seeds with an initial moisture content of 0.42 (d.b) were collected and dried at 40°, 50°, 60°, 70°, and 80°C in a fixed bed experimental dryer. After drying, different mathematical models were fitted to determine the diffusion coefficient by applying liquid diffusion theory, which allowed for calculation of the energy activation, enthalpy, entropy, and Gibbs free energy values. The Page model was selected to represent the drying process of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Activation energy; Effective diffusion coefficient; Guizotia abyssinica Cass; Mathematical models. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000400727 |
| |
|
|
Isquierdo,Eder P.; Caldeira,Daniela S. A.; Siqueira,Valdiney C.; Martins,Elton A. S.; Quequeto,Wellytton D.. |
ABSTRACT This study aimed to obtain and evaluate thermodynamic properties and hygroscopic equilibrium isotherms of urunday seeds as a function of air relative humidity and temperature, as well as identify the best-fitted mathematical models for adsorption phenomenon. A static-gravimetric method was used to obtain hygroscopic equilibrium moisture content. Seeds were placed in airtight containers with different saturated saline solutions for relative humidity control. These were then kept in BOD incubator chambers at 10, 20, 30, and 40 °C. Hygroscopic equilibrium moisture content decreased as temperature increased, for the same water activity. The Sigma-Copace model best-fitted seed adsorption data for equilibrium water activity intervals between 0.1129 and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water activity; Isokinetic; Sorption isotherms; Myracrodruon urundeuva; Relative humidity. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000300374 |
| |
|
|
Jordan,Rodrigo A.; Ribeiro,Evaldo F.; Oliveira,Fabricio C. de; Geisenhoff,Luciano O.; Martins,Elton A. S.. |
ABSTRACT This study had as objective to evaluate the effect of the substrate on the yield of lettuce grown in aquaponic and hydroponic systems. The study was conducted at the Federal University of Grande Dourados, located in Dourados, MS. A randomized complete block design was used, with three treatments and 16 replicates. The cultivation systems were analyzed independently. The substrates analyzed were: coconut shell fiber, phenolic foam and expanded vermiculite. The plants were grown in two systems (aquaponic and hydroponic), using the NFT (Nutrient Film Technique) system. The crop used was lettuce cv. ‘Alcione’. The parameters analyzed were: crop yield and percentage of roots per plant. In addition, macronutrient contents were analyzed in the leaves.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lactuca sativa; Soilless cultivation; Coconut shell fiber; Tilapia. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000800525 |
| |
|
|
Jordan,Rodrigo A.; Geisenhoff,Luciano O.; Oliveira,Fabricio C. de; Santos,Rodrigo C.; Martins,Elton A. S.. |
ABSTRACT In the aquaponic system, the characteristics of the materials used as substrate directly affect plant development, because besides acting as a support base, they must present a surface to fix microorganisms, responsible for the conversion of nutrients into forms more easily available to plants. Thus, the objective of this study was to evaluate the effect of four growing substrates on the yield of lettuce grown in aquaponic system. The experimental design was randomized blocks with four treatments, which corresponded to the substrates, and six replicates. Plants were grown using the nutrient film technique (NFT) system. The substrates used in the experiment were: coconut shell fiber with crushed stone #3, expanded vermiculite, zeolite and phenolic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biofilter; Biodigestion; Soilless cultivation; Intensive fish farming. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000100027 |
| |
|
|
Martins,Elton A. S.; Lage,Eduardo Z.; Goneli,André L. D.; Hartmann Filho,Cesar P.; Lopes,Jéssica G.. |
Propôs-se, neste trabalho, avaliar a cinética de secagem de folhas de timbó (Serjania marginata Casar) e ajustar diferentes modelos matemáticos aos valores experimentais de razão de umidade. As folhas de timbó foram colhidas com teor de água inicial de 2,03 ± 0,10 decimal b.s., sendo submetidas à secagem sob condições controladas de temperatura (40, 50, 60 e 70 ºC), até o teor de água de 0,08 ± 0,02 decimal b.s. Aos dados experimentais foram ajustados dez modelos matemáticos utilizados para representação da secagem de produtos agrícolas. Com base nos resultados obtidos o modelo matemático de Midilli é o que melhor representa a cinética de secagem para as folhas de timbó. O aumento da temperatura promove: uma taxa maior de remoção de água nas folhas de... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Modelo de Midilli; Coeficiente de difusão; Propriedades termodinâmicas; Razão de umidade. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662015000300238 |
| |
|
| |
|
|
Quequeto,Wellytton D.; Siqueira,Valdiney C.; Schoeninger,Vanderleia; Martins,Elton A. S.; Isquierdo,Eder P.; Silva,Fernanda P. da. |
ABSTRACT Buckwheat is a prominent crop in present-day agriculture due to its nutraceutical properties; however, information on this crop regarding the post-harvest process is scarce, as well as the characterization of its physical properties and such information is essential for the development and improvement of machinery used in post-harvest processes. Thus, the objective of this study was to determine the volumetric shrinkage, porosity, bulk density and true density of buckwheat grains throughout the drying process, as well as to fit mathematical models to the experimental values of true and bulk volumetric shrinkages. Buckwheat grains of the cultivar IPR 91 - Baili with an initial moisture content of 0.250 (decimal, dry basis.) were used. The samples... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Post-harvest; Moisture content; Volumetric shrinkage. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018001100793 |
| |
|
|
Martins,Elton A. S.; Goneli,André L. D.; Hartmann Filho,Cesar P.; Mauad,Munir; Siqueira,Valdiney C.; Gonçalves,Alexandre A.. |
ABSTRACT Safflower is an oil crop and its oil can be used for food and industrial purposes. However, there is little information about the physical properties of these grains, which is important for the planning and execution of post-harvest stages. Thus, this study was carried out with the aim of evaluating the effect of drying on the main physical properties of safflower grains. Safflower grains were harvested with an initial moisture content of approximately 0.445 decimal d.b. (dry basis) and subjected to drying in an oven with forced air circulation at 40 °C, until the grains reached a final moisture content of 0.073 ± 0.008 decimal d.b. During the drying, bulk density and true density, porosity, thousand-grain mass, circularity, sphericity, projected... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Carthamus tinctorius L.; Bulk density; Shape of grains. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000500344 |
| |
|
|
Silva,Fernanda P. da; Siqueira,Valdiney C.; Martins,Elton A. S.; Miranda,Fábio M. N.; Melo,Rogerio M.. |
ABSTRACT The aim of this study was to determine the effective diffusion coefficient and the thermodynamic properties of Bauhinia forficata Link leaves, considering two forms of thickness measurements and to describe the process by fitting mathematical models. The leaves were collected, taken to the laboratory and prepared to start the drying process in which four temperatures (40, 50, 60 and 70 °C) were applied. After the drying process, the effective diffusion coefficient was determined through the theory of diffusion in liquid, allowing to obtain the values of the activation energy, enthalpy, entropy and Gibbs free energy. The description of the drying process was performed by setting the thirteen mathematical models used to represent constant drying of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Medicinal plants; Effective diffusion coefficient; Temperature. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000100061 |
| |
|
|
Martins,Elton A. S.; Goneli,André L. D.; Goncalves,Alexandre A.; Hartmann Filho,Cesar P.; Siqueira,Valdiney C.; Oba,Guilherme C.. |
ABSTRACT Blackberry leaves have some pharmacological properties and one of the most widespread and studied uses is to relieve symptoms of the climacteric and other symptoms during the premenstrual period. Thus, drying becomes important for the conservation and storage of the product until its use or processing. The present study aimed to evaluate the drying kinetics of blackberry leaves, as well as to determine the effective diffusion coefficient and the activation energy during the drying process. Blackberry leaves were dried in an experimental fixed-bed dryer under four controlled temperature conditions (40, 50, 60 and 70 °C) and two drying air speeds (0.4 and 0.8 m s-1). With the experimental data of moisture ratio, eight mathematical models were fitted... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Morus nigra L.; Medicinal plant; Air speeds; Midilli model. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000800570 |
| |
Registros recuperados: 12 | |
|
|
|