Applications of fibrous substrates containing insolubilized phase change polymers

Incorporation of polyethylene glycols into fibrous substrates produces several improved functional properties when they are insolubilized by crosslinking with a methylolamide resin or by polyacetal formation by their reaction with glyoxal. The range of molecular weights of polyols that may be insolubilized is broad as are the curing conditions (0.25-10 min at 80-200C). Most representative fiber types and blends (natural and synthetic) and all types of fabric constructions (woven, nonwoven and knit) have been modified by incorporation of the bound polyols. The most novel property is the thermal adaptability of the modified substrates to many climatic conditions. This adaptability is due to the high latent heat of the crosslinked polyols that function as phase change materials, the hydrophilic nature of the crosslinked polymer and its enhanced thermal conductivity. Other enhanced properties imparted to fabrics include flex and flat abrasion, antimicrobial activity, reduced static charge, resistance to oily soils, resiliency, wind resistance and reduced lint loss. Applications commercialized in the U.S. and Japan include sportswear and skiwear. Several examples of electric sets of properties useful for specific end uses are given. In addition, other uses are biomedical horticultural, aerospace, indoor insulation, automotive interiors and components and packaging material

Barium alginate capsules for 3D immobilisation of living cells: morphology, membrane properties and permeability

Encapsulation in a barium alginate membrane is a promising strategy to obtain a three dimensional culture of living cells: membrane properties are crucial for a realistic clinical application. A one-step encapsulation technique, recently developed for controlled release of boar semen, was employed to prepare barium alginate and protamine-alginate membranes: permeability to two model molecules (haemoglobin and glucose) was evaluated. Capsules were evaluated for technological properties and scanning electron microscopy was used to examine the external morphology of the capsules and the 3D distribution of the cells within the core. The results indicate that 3D arrangement and cell shape are maintained, capsule dimensions and mechanical properties can be modulated, as well as their permeability to model molecules such as haemoglobin and glucose

District heating network maintenance planning optimization

To ensure the correct functioning of district heating networks and minimize critical failures, utilities allocate every year a significant part of their budget to maintenance operations. In the present work we describe a risk-based approach implemented to tackle the problem of designing optimal multi-year maintenance campaigns, applied to the Italian city of Brescia, showing how data-driven techniques can help decision makers assess the long terms impacts of budget allocations

La cuestión rururbana: viejas y nuevas prácticas

Los procesos socios económicos y políticos de transformación, que producen migración del campo a la ciudad, implican cambios de prácticas para adaptarse a un nuevo hábitat. Interesa conocer en un caso específico, cómo se efectúan esos cambios, cómo actúan las representaciones sociales adquiridas y cómo se manifiestan en las nuevas prácticas adaptativas. Esta ponencia analiza el impacto de las transformaciones macroeconómicas y sus consecuencias socio territoriales, en un Barrio Estatal de Viviendas de Catamarca mediante método cualitativo con observación participante y entrevistas en profundidad. Se analiza la correlación entre demanda habitacional/respuesta estatal, considerando los avances de los métodos y técnicas de investigación cuantitativa y cualitativa recurriendo asimismo a la triangulación metodológica El hábitat, el lugar en el que se vive influye en la vida cotidiana de las personas y en su calidad de vida, cuando se transforma en problema, se habla de una carencia, porque no pueden resolver por los medios a su alcance, atento a lo dispuesto por la Constitución Argentina, la respuesta debe ser abordada por el Estado Las conclusiones indican que la lógica de la vida cotidiana de los sujetos fundada en su realidad histórica, es una construcción social inacabada y que en los escenarios de cambio espacial, las viejas prácticas y representaciones sociales sostienen el proceso de adaptación hasta que las nuevas son incorporadas. Evidencian la conveniencia del uso de estrategias metodológicas múltiples en el tratamiento de la interrelación oferta/demanda habitacional, porque permiten lograr mayor precisión en la definición de los problemas para formular e implementar respuestas apropiadasJornadas realizadas junto con el I Encuentro Latinoamericano de Metodología de las Ciencias Sociales.Facultad de Humanidades y Ciencias de la Educació

catena-Poly[[chlorido(methyl phenyl sulfide-κS)mercury(II)]-μ-chlorido]

The title compound, [HgCl2(C7H8S)]n, was isolated from the reaction of MeSPh with HgCl2. The HgII atom has a distorted tetra­hedral geometry and is coordinated by one S atom and three Cl atoms. Two of the Cl atoms act as bridging ligands between the Hg atoms, forming a two-dimensional polymeric structure

Estudio proteico de híbridos de girasol cultivados en Argentina

Protein content of residual meals of two sunflower cultivar during two harvest are evaluated. The relation between this component and the oil content of hull, achene and seed are showed. Negative tendency of correlation are observed between hull oil content and hull protein content, on achene oil content and achene protein content and on seed oil content and seed protein content along the harvest studied. Although the protein content for second harvest studied was lower, the apparent competitive behaviour between oil-protein was ratified.Se analizaron los contenidos proteicos de las harinas seminales residuales de extracción, correspondientes a cultivos de girasol (durante dos cosechas), con el fin de estudiar el comportamiento de esta variable en relación con los contenidos de aceite de los constituyentes de la semilla. Se realizaron correlaciones entre los contenidos proteicos de la cáscara, la pipa y la semilla, y la cantidad de aceite que éstos aportan, obteniendo tendencias de correlación negativas entre los mismos. A pesar que los contenidos proteicos obtenidos para la segunda cosecha fueron menores respecto de la primera, el comportamiento aparentemente competitivo entre aceite-proteína se ratificó con similar relevancia

Accuracy estimates for a numerical approach to stochastic growth models

In this paper we develop a discretized version of the dynamic programming algorithm and derive error bounds for the approximate value and policy functions. We show that under the proposed scheme the computed value function converges quadratically to the true value function and the computed policy function converges linearly, as the mesh size of the discretization converges to zero. Moreover, the constants involved in these orders of convergence can be computed in terms of primitive data of the model. We also discuss several aspects of the implementation of our methods, and present numerical results for some commonly studied macroeconomic models.Economic development