Examinando por Materia "Stability"

Mostrando 1 - 3 de 3
  • Miniatura
    PublicaciónAcceso abierto
    Encapsulation of d-limonene flavors using spray drying : Effect of the addition of emulsifiers.
    (Universidad del Valle, 2015-07-31) Rubiano Charry, Karla Daniela; Cárdenas García, Jaime Alberto; Ciro Velásquez, Héctor José
    (Eng) The aim of this study was to evaluate the addition of four emulsifiers (tween 20, tween 60, sodium caseinate and low methoxyl pectin) for the formulation and stability of d-limonene emulsions and to study the emulsifiers' effect on the quality properties of the product obtained by spray drying and on the performance of the process variables. The results of these emulsions were significantly different (p <0.05) in the case of the viscosity and zeta potential, which established, through optimization, that the best formulation is achieved with a mixture of 0.4% low-methoxyl pectin and 0.1% tween 60. The spray drying process was evaluated by varying the inlet air temperature (150-200ºC), outlet air temperature (90-110ºC) and speed of the atomizer disk (20000-30000 rpm). The optimal conditions for the drying process were achieved with inlet and outlet air temperature of 156.7 and 90ºC, respectively, and an atomizer disc speed of 30000 rpm. With these parameters, the following results were obtained: solids recovery (90.9%), percent of deposits (0%), solubility (98.4%), moisture content (2.22% w.b), hygroscopicity (9.2%), water activity (0.112) and encapsulation efficiency (98%), which resulted in a powder with characteristics suitable for industrialization.
  • Miniatura
    PublicaciónAcceso abierto
    Propuesta metodológica de Restauración Ecológica en los Páramos del Volcán Chiles, Nariño.
    (2011) Baca, Aida Elena
    A partir de conceptos como Teoría general de sistemas, sistemas complejos y ecología de la restauración, se propone una metodología para recuperar zonas degradadas por disturbios antrópicos en paramos. Para ello se describe el ecosistema, su problemática y las acciones que conducirán a determinar cuáles son los sitios, especies y condiciones de clima que favorecen en un proceso de restauración ecológica para que el ecosistema paramuno se regenere más rápidamente. Abstract Since concepts such as general systems theory complex systems and restoration ecology, proposes a methodology to recover degraded areas by anthropogenic disturbances in páramo. We describe the ecosystem, their problems and actions that will lead to identifying the sites, species and weather conditions that favor a process of ecological restoration for that the páramo ecosystem will can to regenerate faster
  • Miniatura
    PublicaciónAcceso abierto
    Stability of the feasible set in balanced transportation problems.
    (2011-09-14) Gómez y Estrada, Soraya; Hernández Rebollar, Lidia Aurora; Lancho Romero, Guillermo Arturo
    In this paper we study the stability of the feasible set of a balanced transportation problem. A transportation problem is balanced when the total supply is equal to the total demand. One can easily see that when we make minor adjustments to the data (supply and demand), the resulting problem may lose the property of balance. Therefore, although the transportation problem is a particular case of linear programming, you cannot apply the familiar results of stability. For a fixed number of origins and destinations we have obtained a vector representation for any feasible solution of the transportation problem. We have used this representation to prove that the feasible set mapping is continuous. We have also proved that the extreme point set mapping is lower semi continuous.1