Optimización del rendimiento de la extracción acuosa enzimática de aceites de açaí mediante cocciones utilizando un diseño experimental

These last decades, açaí oil has been extensively studied for its biological properties and has gained interest from the health industry. It has thus become necessary to develop eco-friendly extraction techniques. The main objective of this study was the use of experimental designs for the maximization of the recovery yield of the enzymatic aqueous extraction process of açaí oil from wet decocts. A Simplex-Lattice Mixture Design was employed for the optimization of the proportion of three commercial enzymatic preparations. Subsequently, a Central Composite Design was used to identify the optimal values for total enzymatic concentration (0.5-4.5%) and extraction time (2-12h). The “Response Surface Methodology” (RSM) revealed that the maximum yield (60.55 ± 5.98%) was obtained using a 0.49:0.25:0.28 ternary mixture of Celluclast 1.5 L, Viscozyme L and Ultrazym AFP-L at a total enzymatic concentration of 2.85% for 10.9 hours. This study concluded that the enzymatic aqueous extraction of açaí oil is an efficient and sustainable process.En las últimas décadas, el aceite de açaí ha sido ampliamente estudiado por sus propiedades biológicas, resultando interesante para las industrias relacionadas con la salud. Por lo tanto, se ha vuelto necesario desarrollar técnicas de extracción ecológicas. El objetivo principal de este estudio es el uso de diseños experimentales para la maximización del rendimiento en la recuperación del proceso de extracción acuosa enzimática del aceite de açaí a partir de cocciones. Se emplea un diseño de mezcla simplex-lattice para la optimización de las proporciones de tres preparaciones enzimáticas comerciales. Posteriormente, se utiliza un Diseño Compuesto Central para identificar los valores óptimos de la concentración enzimática total (0,5-4,5%) y el tiempo de extracción (2-12h). La “Metodología de superficie de respuesta” (RSM) señala que el rendimiento máximo (60,55 ± 5,98%) se obtiene utilizando una mezcla ternaria 0,49:0,25:0,28 de Celluclast 1,5 L, Viscozyme L y Ultrazym AFP-L a una concentración enzimática total de 2,85% durante 10,9 horas. Este estudio indica que la extracción acuosa enzimática del aceite de açaí es un proceso eficiente y sostenible

Third Annual Report of the Farm Management Service for Farmers in Soil Conservation Demonstration Areas for the year 1937 (April 1937 to March 1938)

Farm Management,

First grade reading materials of high interest level for children from the ages of seven through twelve.

Thesis (Ed.M.)--Boston Universit

Anomalous Suppression of Valley Splittings in Lead Salt Nanocrystals without Inversion Center

Atomistic sp3d5s* tight-binding theory of PbSe and PbS nanocrystals is developed. It is demonstrated, that the valley splittings of confined electrons and holes strongly and peculiarly depend on the geometry of a nanocrystal. When the nanocrystal lacks a microscopic center of inversion and has T_d symmetry, the splitting is strongly suppressed as compared to the more symmetric nanocrystals with O_h symmetry, having an inversion center.Comment: 5 pages, 4 figures, 1 tabl

Thermal emission spectroscopy of the middle atmosphere

The general objective of this research is to obtain, via remote sensing, simultaneous measurements of the vertical distributions of stratospheric temperature, ozone, and trace constituents that participate in the catalytic destruction of ozone (NO(sub y): NO, NO2, NO3, HNO3, ClONO2, N2O5, HNO4; Cl(sub x): HOCl), and the source gases for the catalytic cycles (H2O, CH4, N2O, CF2Cl2, CFCl3, CCl4, CH3Cl, CHF2Cl, etc.). Data are collected during a complete diurnal cycle in order to test our present understanding of ozone chemistry and its associate catalytic cycles. The instrumentation employed is an emission-mode, balloon-borne, liquid-nitrogen-cooled Michelson interferometer-spectrometer (SIRIS), covering the mid-infrared range with a spectral resolution of 0.020 cm(exp -1). Cryogenic cooling combined with the use of extrinsic silicon photoconductor detectors allows the detection of weak emission features of stratospheric gaseous species. Vertical distributions of these species are inferred from scans of the thermal emission of the limb in a sequence of elevation angles. The fourth SIRIS balloon flight was carried out from Palestine, Texas on September 15-16, 1986 with 9 hours of nighttime data (40 km). High quality data with spectral resolution 0.022 cm(exp -1), were obtained for numerous limb sequences. Fifteen stratospheric species have been identified to date from this flight: five species from the NO(sub y) family (HNO3, NO2, NO, ClONO2, N2O5), plus CO2, O3, H2O, N2O, CH4, CCl3F, CCl2F2, CHF2Cl, CF4, and CCl4. The nighttime values of N2O5, ClONO2, and total odd nitrogen have been measured for the first time, and compared to model results. Analysis of the diurnal variation of N2O5 within the 1984 and 1986 data sets, and of the 1984 ClONO2 measurements, were presented in the literature. The demonstrated ability of SIRIS to measure all the major NO(sub y) species, and therefore to determine the partitioning of the nitrogen family over a continuous diurnal cycle, is a powerful tool in the verification and improvement of photochemical modeling

KINEMATIC TRENDS IN ELITE SPRINTERS

During the 1982 and 83 outdoor track and field seasons, selected Olympic caliber men (n>15) and women (n > 20) sprinters (100m-400m) were filmed in up to five top level competitions. These athletes were subsequently biomechanically analyzed under a grant from the United States Olympic Committee. The purpose of this effort, termed the Elite Athlete Project, was to provide feedback to the involved athletes regarding their strengths, weaknesses, and potential areas of performance improvement

Gas-Kinetic-Based Traffic Model Explaining Observed Hysteretic Phase Transition

Recently, hysteretic transitions to `synchronized traffic' with high values of both density and traffic flow were observed on German freeways [B. S. Kerner and H. Rehborn, Phys. Rev. Lett. 79, 4030 (1997)]. We propose a macroscopic traffic model based on a gas-kinetic approach that can explain this phase transition. The results suggest a general mechanism for the formation of probably the most common form of congested traffic.Comment: With corrected formula (3). For related work see http://www.theo2.physik.uni-stuttgart.de/helbing.htm