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Copyright of Revista Complutense de Educación is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

INTRODUCCIÓN. La educación artística influye beneficiosamente en el desarrollo integral del ser humano. Sin embargo, existe una carencia por lo que respecta a su investigación, como también lo es respecto al conocimiento de estas ventajas. Por ese motivo, es de especial relevancia examinar la actitud de los futuros maestros sobre el arte, o de forma más concreta, en cuanto a su didáctica. No obstante, hasta el momento no se han encontrado escalas que evalúen, desde una metodología cuantitativa, las actitudes con respecto a la Didáctica de la Expresión Plástica. Por ese motivo, este trabajo tuvo como objetivo diseñar y validar la Escala breve de Actitudes sobre la Didáctica de la Expresión Plástica (EADEP) y observar la invarianza entre sexos. MÉTODO. Para ello, se partió de una muestra de 190 futuros docentes (Medad = 20.05; DT = 3.67) para un primer estudio y 790 (Medad = 19.88; DT= 4.03) para un segundo. RESULTADOS. El primero de ellos arrojó un factor para la EADEP con adecuadas propiedades psicométricas. El segundo de ellos indicó un buen ajuste de los datos para la estructura unidimensional de la EADEP, manteniéndose invariante en función del sexo. CONCLUSIÓN. Se ofrece, por tanto, un instrumento de medida válido y fiable para la actitud hacia la Didáctica de la Expresión Plástica y se reflexiona sobre la necesidad de aumentar los estudios en este campo.

In this article, a bibliographical review of some methodologies of design of experiments is carried out, focusing on its function and relevance within the experiments, where the importance of the designs of experiments within the investigation is highlighted using examples of the strategies and designs of experiments. In the first place, a review was carried out that would allow the introduction of the concept of design of experiments, how it was conceived, its principles and its relationship with the investigation, including the main elements of which designs of experiments are composed, and some assumptions to be considered at the time of apply an experimental design in research are included. In addition, different methodologies used by some authors in experiments are shown, what they are and a basic notion of the different methodologies used in the research, focusing on the differences between each one of them and why to use them according to the need of the experiment, then from this, different examples of the different experimental design methodologies used in research articles focused on polymeric materials were carried out, in these examples the different variables of the experiment were stood up, what was the purpose of the investigation and why they opted for the design of experiments they mention. Finally, after carrying out the bibliographical review, it was found that in most of the experimental design applied to the field of experimentation, it allows optimizing the resources without the need to make many attempts. In fact, depending on the type of experiment, it will be feasible to choose a design that is accommodate the needs of the researchers, according to the objectives set in the experiment. [ABSTRACT FROM AUTHOR]

In this paper, we present an experimental study and statistical modeling of High-Performance Concrete subjected to high temperatures. The main objective of this study is to examine the effect of concrete age subjected to high temperature cycles (ranging from 20 °C to 1000 °C) on the physical and the mechanical properties of (HPC). The compressive strength, flexural strength, dynamic modulus and the physical characteristics were evaluated based on the mass loss and ultrasonic pulse velocity. The experiments have been performed at different age 90 and 210days. The analysis of the results shows that increasing temperature decreases the mechanical properties of the concrete especially after 90 days. The factorial design and analysis of variance (ANOVA) were used to establish the influence of experimental parameters on the HPC. Based on several criteria, mathematical models can be used to predict HPC properties under high temperature. [ABSTRACT FROM AUTHOR]

La falta de conocimiento en cuanto a los intervalos de macronutrientes como nitrógeno (N), fósforo (P) y potasio (K) aplicados al maíz es una de las falencias que no permiten aprovechar la potencialidad de semillas certificadas, lo cual se complica aún más cuando no se utilizan los diseños experimentales adecuados para establecer dichos intervalos. Ante esta situación se desarrolló esteensayo con un arreglo factorial incompleto de segundo orden denominado diseño central compuesto (DCC), con el fin de identificar intervalos de macronutrientes para una mayor producción de maíz. Se empleó una distribución de bloques completos al azar, en los cuales se probaron 15 formulaciones (tratamientos) de N-P-K con tres repeticiones de cada una y como variable de respuesta se evaluó el rendimiento de grano seco. Los datos se valoraron mediante análisis de varianza para detectar efectos lineales y cuadráticos, se obtuvieron las respectivas superficies de respuesta y gráficas de contorno y se ajustó un modelo de segundo orden. Se estableció que los rendimientos de maíz más altos, ubicados entre 10 y 11 t/ha, se obtienen cuando se aplican entre 110 a 140 kg/ha de nitrógeno, de 50 a 70 kg/ha de fósforo y de 100 a 140 kg/ha de potasio. Además, se corrobora la bondad del DCC cuando se conocen los límites de operatividad experimental de los factores de estudio.

Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Investigaciones Agroindustriales is the property of Revista Colombiana de Investigaciones Agroindustriales del Centro Agropecuario Sena Buga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, a novel experimental approach for the optimal selection of an actuator-based control strategy is presented. The proposed approach is a two-stage method: first, a two-level factorial experiment design with n factors (2n) was applied to compare different control schemes. Schemes comparison was carried out in terms of energy consumption and closed-loop performance. For the best relative scheme, a Central Composite Face-centered (CCF) design was completed obtaining the controller parameters that optimize the performance in terms of the Integral Absolute Error (IAE) while operating in a region of low energy consumption. The proposed approach was experimentally tested using real data obtained from a laboratory prototype plant. Some experimental tests illustrating the suitability of our method are shown at the end of this article. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La presente investigación tuvo como objetivo determinar si el costo conductual influye la elección del modo de interacción y el efecto de la adicción a las redes sociales sobre ésta. Para la selección de la muestra se aplicó el Cuestionario de Adicción a las Redes Sociales (ARS) a 306 estudiantes universitarios, 140 hombres y 166 mujeres con edades comprendidas entre los 18 y 42 años (X=22,34), luego se organizaron los puntajes en cuartiles y se seleccionaron a nueve personas del primer cuartil y nueve del último cuartil. Una vez hecho esto, se asignaron en grupos de tres personas, y cada grupo fue asignado dentro de una condición del diseño factorial. El experimento consistió en realizar una entrevista que podía contar con 10 o 16 preguntas (costo conductual), donde el participante elegía realizarla a través de una red social o de forma presencial, dependiendo de la condición asignada. En el análisis de resultados se utilizó el estadístico Kruskal – Wallis y la prueba U de Mann - Whitney para establecer si existen diferencias entre la elección por costo conductual y los cuartiles elegidos respectivamente. Los resultados demostraron que la elección tiende a ser por la opción menos costosa, sin importar la presencia, o ausencia, de adicción a las redes sociales.

Although researchers have widely studied the analysis and modeling of error sources on Global Navigation Satellite Systems positioning, some of these errors have not been eliminated significantly. Only some of the Global Navigation Satellite System's data are modeled. The present work was undertaken to determine the effect of different variables: season, the number of visible satellites, and dilution of precision on the efficiency of horizontal and vertical CORS (Continuously Operating Reference Stations) positioning. The CORS data was collected at 14 different test points during 600 epochs with 1-second intervals for this aim. Factorial designs supply an efficient solution to understand the impact of several factors on a response variable. A full factorial design with three factors at two levels was applied for these purposes. The main and the interaction effects of factors were analyzed on the CORS horizontal and vertical positioning. According to the full factorial design results, while all main and interaction effects of factors significantly affected the CORS horizontal positioning error, some elements did not affect the CORS vertical positioning error. Also, the regression equations were obtained for all situations to investigate the other level of selected factors in the response variables. [ABSTRACT FROM AUTHOR]

El estudio es un diseño experimental que explica si los factores día de la película y tipo de sala influyen en la percepción de la calidad de las salas de cine; para evaluar la percepción de los elementos de la calidad de un servicio se utilizó una escala. El cine es una de las alternativas más frecuentadas de consumo de ocio en Colombia (DANE); la importancia del estudio es contribuir con información para que las salas de cine puedan tomar decisiones asertivas que les permitan implementar estrategias que respondan a los elementos claves que influyen en la satisfacción esperada por la demanda. Con un nivel de significancia del 5 %, se descubrió que las dimensiones tangibilidad y capacidad de respuesta influyen en la percepción de la calidad del servicio de cine. Los hallazgos le permiten a la gerencia de las salas administrar discrecionalmente los factores influyentes en la calidad percibida.

The use of rhamnolipids constitutes an attractive and eco-compatible alternative in the remediation of contaminated environments with heavy metals. In the present work, the ability of rhamnolipid produced by P. aeruginosa ORA9 to remove copper in contaminated waters of the Blue Lagoon of El Cobre, was evaluated, to control and reduce the human and environmental risk that these waters represent. The influence of the pH of the rhamnolipid solution (4-10), the contact time (2-10 hours) and the concentration of the biosurfactant (40-120 mg L-1) in the process were studied, through a factorial design Box-Bhenken. An increase in the percentage of copper removal proportional to the contact time and the concentration of the biosurfactant was observed, reaching 48 % removal at 10 h and 120 mg L-1. The results obtained indicate that rhamnolipids can be used in the design of a technology to remove copper in polluted contaminated waters. [ABSTRACT FROM AUTHOR]

Zeaxanthin is an oxygenated carotenoid which may play a critical role in the prevention of cancer and agerelated macular degeneration, the leading cause of blindness in the developed world. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the present study was to develop and to characterize the floating raft system (FRS) of Amoxicillin to enhance gastric residence time and drug release to target Helicobacter pylori effectively. Method: In the present study, guar gum, glyceryl monostearate (GMS), calcium carbonate were selected as factors. Gelation duration (h), floating lag time (min), and % Cumulative drug release (CDR) were selected as responses. 23 factorial design with replicates was selected for experimentation. Results: It was observed that guar gum and GMS were the major factors affecting gelation duration, increase in the quantity of both guar gum and GMS increased gelation duration i.e., sustained gelation period (24 h). Floating time increased with an increase in the amount of guar gum and calcium carbonate, whereas an increase in the quantity of GMS decreased floating time. Guar gum, calcium carbonate, and GMS exhibited an antagonistic effect on % CDR. Contour plots were used to identify design space; further numerical analysis yielded 12 best solutions based on desirability. FRS exhibited greater AUCo-t, Cmax, tmax, and t1/2 when compared to marketed formulation approximately 2.30 folds enhancement and prolongation with a sustained release for greater than 24 h that might be due to better gelation. Conclusions: It can be concluded that the floating raft system was successfully developed by the Design of experiment (DoE) application with fewer trails and by utilizing easily available excipients for better floating, gelation, and sustained delivery of the drug. [ABSTRACT FROM AUTHOR]

Optimization of the steam quinoa cooking process was carried out, using a response surface design (RSM) 3-level: 3k factorial, and the multiple response optimization methodology of the desirability function (Dx) was used to find the optimal region, which are improved tools to optimize the variables of a process, evaluate the maximization of the water absorption index (WAI), water solubility index (WSI), degree of gelatinization (GE) and the minimization of cotyledon detachment (DC) of quinoa (Chenopodium quinoa Willd). The equipment used was a vertical cook with a steam generator, the study cooking variables, the steam pressure, and the cooking time. The optimal process values were: Pressure 1.5 kgf.cm-2 and time 8 minutes for the best characteristics of cooked quinoa WSI of 26.411%, WAI of 7.960 (g.g-1), GE of 89.245% and CD of 18.40%, the value of the desirability function as an indicator of multiple responses was 0.798. Knowledge of these characteristics can be a valuable complement in the cooking process and thus contribute to improving the quality of cooked cereals. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of an enzymatic pre-treatment process for the extraction of oil from black mustard seeds (Brassica nigra) using viscozyme, the reaction parameters such as temperature, buffer-to-seed ratio and enzyme concentration were considered as determinant factors in the central composite design. Optimization was carried out according to the four-variable five-level central composite design of experiments. The effects of enzyme concentration (5-12%), temperature (40-55 °C), pH (5.0-6.0), and reaction time (1-7 h) on the free oil liberated were studied. Residual oil was collected by subjecting the treated meal to soxhlet extraction for 4 h. An enzyme dose of 7.5% (w/w), pH 5.0, 50 °C, and 5 h with constant shaking at 450 rpm were found to be optimal conditions. Centrifuging the mixture at 7000 rpm for 30 min separated the oil with a recovery of 71-73.1%. [ABSTRACT FROM AUTHOR]

The objective of this work was to obtain a predictive model of the production of maltodextrins, measured as dextrose equivalents (ED), in terms of four factors: enzyme concentration, substrate concentration, temperature and time of digestion whose minimum and maximum levels were 20 and 30% m/m, 0,01 and 0,03%, 40 and 60°C, 15 and 30 minutes respectively. The substrate was obtained from the pulp of cassava tubers (Manihot esculenta Crantz), which was characterized and used as raw material to produce starch solutions at 10, 20 and 30% m/m, which were hydrolysed with commercial alpha amylase (300 NKU/g) to produce the maltodextrins. A factorial design 24 was used, and by means of ANOVA and the software Minitab 17 it was determined that all the factors and their interactions, except the interaction temperature-concentration of substrate, were statistically significant for a α = 0,05. Mathematical expression was simplified by considering the factors and their most effective interactions; these being the Temperature, Enzyme Concentration, Time, Substrate Concentration, and the Interaction Temperature-Concentration of enzyme; thus the mathematical model remained as: ED=0,454375+0,128781 x temperatura-0,060186 x [sustrato]-10,249998 x [enzima] +0,065625 x tiempo +5,753121 x temperatura x [enzima] with a deviation s = 0,197, an R² = 99,78% and an average error rate of 1,18%. The model was validated through a residual analysis; as well as using published works, finding good reproducibility in two cases, even when the substrate was not yucca but yam. [ABSTRACT FROM AUTHOR]

El objetivo del siguiente artículo es evaluar la influencia de los parámetros de tiempo y tipo de electrolito en el espesor y dureza de la película generada por oxidación anódica, sobre la aleación de aluminio AA5083-H116. Fueron evaluados electrolitos, tipo oxálico y fosfórico con tiempos de 30 y 45 min de anodizado. La morfología de las películas fue observada mediante microscopía electrónica de barrido (MEB). La dureza de las superficies se evaluó mediante ensayos Vickers. Para validar los resultados fue aplicado un diseño factorial 2². Los resultados mostraron que el electrolito tipo oxálico presenta los mayores valores de espesor y dureza. [ABSTRACT FROM AUTHOR]

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El propósito de este estudio es evaluar el proceso de deshidratado osmótico para la reducción de mermas de una empresa agroalimentariade la zona dedicada a la elaboración y comercialización de frutos deshidratados infundidos. En la evaluación del proceso, se determinaron las variables que condicionan la etapa de lavado posterior al deshidratado de la fruta.Utilizando un diseño factorial fraccional 2x como herramienta de evaluación y disminución de las mermas del proceso de deshidratación osmótica, se analizaron el efecto del caudal de fruta (gr/s), caudal de agua (L/h) y el número de pasadas de la fruta infundida, en el brix superficial.Los resultados obtenidos demuestran la efectividad que tiene la integración de las técnicas de diseño de experimentos en la definición de parámetros operacionales del proceso productivo. De los resultados obtenidos, la condición que proporciona el brix más cercano al esperado (2,7 °Bx), corresponde a la alternativa que considera una fila de aspersores abiertos (4 aspersores), utilizando un caudal de 868,747 gr/s y1054,74 L/h de fruta y agua respectivamente y 2 pasadas por el shakerpara la reducción de mermas en el proceso.

The degree of hydrolysis (DH) of rainbow trout viscera (Oncorhynchus mykiss) using Alcalase 2.4L, Flavourzyme and Neutrase. Alcalase 2.4L presented higher DH compared with Flavourzyme and Neutrase. Therefore, the process using Alcalasa 2.4L was optimized according to temperature and pH, finding a maximum DH of 24% at pH 8.5 and 45°C in a 500 mL reactor. The process was scaled to a reactor of 7.5 L, in which the effects of the the stirring speed (75-200 RPM) and the presence of deflectors were evaluated. The results indicate that the model satisfactorily fits the DH values in the levels analyzed (R² = 0.96). The DH depends on pH, temperature, type of enzyme, speed of agitation, work scale and presence of baffles in the reactor. This information is of importance for designing the enzymatic hydrolysis processes of an specific substrate. [ABSTRACT FROM AUTHOR]

Blueberry (Vaccinium meridionale) forms part of the family Ericaceae; it is a fruit rich in flavonoids and anthocyanins (polyphenols), which have antioxidant properties and also shows some properties suitable for inhibition of free radicals. A 2³ factorial design was performed to investigate the variables effects: temperature, time and the ethanol percentage %, on the antioxidants extraction process by Microwave Assisted Extraction (MAE). The extraction conditions were: temp (343.15-383.15 K), time (5-15 min), ethanol (0- 80%). A factorial design was performed, with a total of 8 experiments, allowing to determine the influence of the relation of the variables related to the extraction process of compounds with antioxidant activity by DPPH· method, getting a first order factorial model with interactions and a 100% reliability level and a R² =1. The experimental design and evaluation of the results were performed with the software R Studio? free version. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate nanofiltration using permeate of ultrafiltration treatment of residual brine from making table olives process model solutions. For the experiments realization a factorial design of two levels was considered (2³). The following independent variables were selected: operating pressure, tangential velocity and membrane type. The response variable was permeate flux density. In addition, the Half-Daniel graphic method was used to determine the significant effects. The permeability coefficients of NF 270, NF 245, NF 90 membranes are 9.93, 3.47 and 3.45 L/hm²bar, respectively. The NF 270 membrane has the highest permeability, while the NF 245 and NF 90 have similar values. The standardized effects of the studied factors estimation on the flow density showed that the variables: type of membrane, pressure and its interaction have the greatest influence on the permeate flow density under considered conditions. The liquid tangential velocity and the remaining interactions also have significant effects, but to a lesser degree. The factorial model was significant (pvalue < 0.0001) for a correlation coefficient R² equal to 0.98. This implies that 97.90% of total variation in the studied process was attributed to considered factors. The model is adequate to represent the experimental data with a confidence level of 95%. [ABSTRACT FROM AUTHOR]

The results of a research into the cyanide leaching of a sulphurous gold ore with carbonaceous matter are shown. An experimental design of factorial analysis 2k of three variables with replicates in the center was applied, using the response surface method (MRS). Cyanidation tests in rotating bottles were conducted to study the effect of certain selected variables on Au recovery and to determine the optimal parameters to achieve maximum Au recovery in the process. The results obtained show that the mineral presents a high degree of cyanide leachability, obtaining an average Au recovery of 93.65%, with a sodium cyanide [NaCN] concentration of 2.5 g/L and a leaching time of 12 hours. [ABSTRACT FROM AUTHOR]

Titanium alloys are widely used as biocompatibles materials, due to their chemical stability inside of the body, a good relationship between density/resistance, fatigue resistance, corrosion resistance and other. The capacity of these materials to develop a naturally passive oxide layer on the surface, makinge them favorable for different applications. However, the stability of the film is affected by aggressive environment. Therefore, the surface modification process has been an alternative to improve the corrosion resistance, and some mechanical properties. This research evaluated the effect of the heating rate on the thermal oxidation of titanium alloys (Ti6Al4V). The method consisted in producing oxide films by thermal oxidation at 600, 700 and 800°C at different heating rates 3, 4 and 5 °Cmin-1 and isothermal cooling in furnace. Morphological characterization was carried out through Scanning Electronic Microscopy, and the corrosion resistance test was carried out by potentiodynamic polarization study using Ringer's solution as an electrolyte. The results showed the influence of the temperature and heating rate on the thickness of the oxide layer in factorial design 3². Thermally oxidized samples at 600 and 800°C showed the best results regarding corrosion resistance compared to untreated samples, and the hardness increased 2.5 fold in samples oxidized at 800°C compared to the base alloy. [ABSTRACT FROM AUTHOR]

The surface methodology of response to the factorial design was used to relate the catalytic activity in a two-way catalyst and the following process parameters: concentration ratio La2O3 / Cu and La2O3 / Al; matrix weight; impregnation time; the calcination temperature. The factors that influenced directly under the CO reduction efficiency were studied. The objective was to identify the process factors, which had the greatest effect, in the adition to evaluating the interaction between them. It was observed that there is an increase of 0.195%, on average of the CO reduction when the concentration ratio varies from 0.5g to 1.25g and there is an increase of 0.47%, on average, of the CO reduction when the impregnation time varies from 6h to 12h. It is also observed that the effect of the block is significant but negative, there is a significant decrease of 3,7%, in average, in the reduction of CO when using the ratio La2O3 / Al confirming that the catalyst with the aluminum metal presents higher catalytic efficiency in CO reduction. It was also observed that there is an interaction between the immersion time and the calcination temperature and that it had a synergic effect. The linear correlation was determined by the following mathematical equation: y = ... . [ABSTRACT FROM AUTHOR]

Copyright of Comunicaciones en Estadística is the property of Universidad Santo Tomas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Urban agriculture promotes the cultivation of vegetables in the city, however seeds are required to germinate and obtain seedlings that allow to start this practice. Objective. The present research evaluates the percentage of germination of two varieties of lettuce (Lactuca sativa), Milanesa and Conconina, to determine if there is a significant difference in their germination to obtain seedlings. Materials and methods. A factorial design 22 was developed, taking into consideration the combinations of variety and luminosity; a statistical model was proposed to describe its behavior. Results. The most influential factor in the percentage of germination is the variety, the best results were found Milanesa variety under natural Light conditions. Conclusions. The Milanesa variety is a good option to generate seedlings and, under natural Light conditions, a germination percentage of 92.5% can be obtained, a value higher than that reported by the producer. [ABSTRACT FROM AUTHOR]

El objetivo de este estudio fue evaluar la nanofiltración mediante el uso de soluciones modelos del permeado de la ultrafiltración en el tratamiento de salmuera residual del proceso de elaboración de aceitunas de mesa. Para la realización de los experimentos se consideró un diseño factorial de dos niveles (23 ). Como variables independientes fueron seleccionadas: la presión operación, velocidad tangencial y tipo de membrana. La variable de respuesta fue densidad de flujo de permeado. Además, se usó el método gráfico de Half-Daniel para determinar los efectos significativos. El coeficiente de permeabilidad de las membranas NF 270, NF 245, NF 90 es de 9,93; 3,47 y 3,45 L/hm2 bar, respectivamente. Siendo la membrana NF 270 la de mayor permeabilidad, mientras que la NF 245 y NF 90 presentó valores similares. La estimación de los efectos estandarizados de los factores estudiados sobre la densidad de flujo arrojó que las variables: tipo de membrana, presión y su interacción ejercieron mayor influencia sobre la densidad de flujo de permeado en las condiciones consideradas. La velocidad tangencial del líquido y las interacciones restantes presentaron efectos significativos, pero en menor grado. El modelo factorial resultó significativo (p-valor < 0,0001) para un coeficiente de correlación R2 igual a 0,98. Lo que implica que el 97,90% de la variación total en el proceso estudiado se atribuyó a los factores considerados. Por lo que se concluye que modelo es adecuado para representar los datos experimentales con un nivel de confianza del 95%.

Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)