Enfoque UTE

pp. 79 - 89

Authors: Maria Belén Quelal, Karina Nazate, Clara Elena Villacrés

The present research focused on obtaining a hydrolyzate from a quinoa protein concentrate (isoelectric precipitation method), while the hydrolyzate was achieved with the application of papain enzyme in different concentrations and temperature. The nutritional and functional properties were evaluated in the hydrolyzate, establishing the fact that application of enzyme at a concentration of 0.159 AU/g and pH 6.5 allowed to reach a hydrolysis rate of 13 %, a protein content of 73.41 g/100 g, digestibility rate of 87.75 %, and an amino acid profile within the standard requirements established for children, according to FAO. The functional properties of the hydrolyzate reflected an index of dispersibility of 83.71 %, protein solubility of 85.35 %, foaming capacity of 125 % volume at pH 10, water retention capacity of 0.33 g/g protein and oil holding capacity of 0.56 g/g protein. These values ​​show the potential of the protein hydrolyzate in the elaboration of food formulas for diets with special regimes or as an ingredient in the food industry.

pp. 1 - 16

Authors: Mónica Susana Delgado Yánez, Miguel Martínez-Fresneda Mestre, Antonio Villaruela

The present paper is a proposal of socio-economic sustainability of the water resource of the Magdalena lagoon in the Atillo lake complex of the Sangay National Park in the province of Chimborazo, by means of the indirect method of travel costs. In this study, spatial indicators of hydric situation are established and homogeneous units are established with GIS techniques, in order to find the optimal distance to apply the concentric circle methodology in the use of the econometric tool of travel costs. According to the image analysis, it can be concluded that the lake is in retreat; however, it still has limnimetric limits that are still stable. Because of this, it is proposed to limit the number of visits to the area to less than 300 per month and cost opportunity is proposed, for socio-economic sustainability, from the homogeneous units, where the price is considered by estimating the market price, the result being equal to the cost of the trip + Cost of travel time, based on the average stay time that does not exceed one day for the support of the ecosystem

pp. 28 - 38

Authors: Juan Rocha-Hoyos, Edilberto Antonio Llanes-Cedeño, Jefferson Andrade-Villarreal, Luis Caiza-Quishpe, Julio Leguísamo-Milla

The purpose of the study was to analyze the deposits in injectors with fuel mixture of 87 octane with percentages of anhydrous ethanol at 5 %, and 87 octane gasoline. The experimental phase was carried out in two ignition engine vehicles at a test height of 2810 msnm when traveling, each one, a distance of 3000 km inside the Metropolitan District of Quito. Two methods were applied: Stereoscopy or Vision for the analysis of the microfilters of the injectors, and the semiquantitative chemical analysis Scanning Electron Microscopy for the samples of the residues originated in the filters. In the case of Stereoscopy, in both vehicles, a reduction of clogging of the filters occurred when using gasoline with 5 % anhydrous ethanol. The Scanning Electron Microscopy allowed to conclude that there is a greater presence of the sulfur element with 4 % in the residues when using gasoline with 5 % ethanol, unlike 1 % in the waste when 87 octane gasoline is applied.

pp. 115 - 125

Authors: Gabriel Serpa, Xavier Zumba, Francisco Montalvo, Daysi Baño, Jorge Martinez, Iván Zambrano

This research was made in Cuenca at 2500 meters above sea level (masl), and it studied the influence of the use of different types of spark plugs in a spark-ignition engine on the mechanical performance of the engine, the pollutant emissions, and fuel consumption. Six types of spark plugs that are available in the national market are made of different materials, have different thermal properties, and have different electrode openings. In addition, the mechanical performance of the engines and their fuel consumption were evaluated through dynamometer testing. Moreover, the polluting emissions were measured under the static test protocol established by the NTE INEN 2203 and with an 11 km route test in urban areas and on highway based on the New European Driving Cycle. The research showed that a specific spark plug increases 16 % of the engine performance due to not only some factors such as less pollution, better cold behavior, lower fuel consumption, but also maintains the torque and power of the vehicle. In addition, this spark plug generates savings on maintenance and annual fuel consumption.

pp. 63 - 78

Authors: Anabel Sarahis Reyes Sisco, José Antonio Ruiz Arenas, Luis Antonio Castillo Campos

Nowadays, mineral incrustations are one of the most frequent problems in the petroleum industry; they deteriorate the production systems, causing pressure losses and, consequently, the decrease of hydrocarbon production. Based on this problem, this research was conducted with the purpose of evaluate the efficiency of a natural scale inhibitor based on the leaf mucilage of the cayenne plant (Hibiscus rosa sinensis) in synthetic and production water samples. In order to do this, the physical-chemical characterization on the water samples was carried out, as well as the mucilage previously extracted from the plant. Subsequently, the natural inhibitor was formulated and characterized at three different concentrations (2, 4 and 6 % m /V) and the efficiency of the product was evaluated in both water samples, considering three (3) different doses (55, 100 and 500 ppm) following the guidelines of the NACE standard TM0347-2007, with the result that the inhibitor of 2 % m/V was the most efficient at its highest dose. In addition, the commercial inhibitor from Halliburton Company was used for comparative purposes in a statistical analysis that indicated the absence of a significant statistical difference between the product at 2 % m / V and the commercial inhibitor.