3,546 research outputs found
Diatomite releases silica during spirit filtration
The purpose of this study was to ascertain whether diatomite is an inert filter aid during spirit filtration. Surely, any compound with a negative effect on the spirit composition or the consumer’s health could be dissolved. In this study different diatomites were treated with 36% vol. ethanol/water mixtures and the amounts and structures of the extracted compounds were determined. Furthermore, Brandy de Jerez was diatomite- and membrane-filtered at different temperatures and the silicon content was analysed. It was found that up to 0.36% by weight of diatomite dissolved in the aqueous ethanol and amorphous silica, in the form of hollow spherical microparticles, was the most abundant component. Silicon concentrations in
Brandy de Jerez increased by up to 163.0% after contact with diatomite and these changes were more marked for calcined diatomite. In contrast, reductions of more than 30% in silicon concentrations were achieved after membrane filtration at low temperatures
Formation of siliceous sediments in brandy after diatomite filtration
Brandy is quite a stable spirit but sometimes light sediment appears. This sediment was separated and analysed by IR and SEM-EDX. It was revealed that the sediment is composed mostly of silica and residual organic matter. Silica was present as an amorphous phase and as microparticles. In an attempt to reproduce the formation of the sediment, a diatomite extract was prepared with an ethanol/water mixture (36% vol.) and a calcined diatomite similar to that used in brandy filtration. This extract was added to unfiltered brandy in different amounts. After 1 month, the Si concentration decreased in all samples and sediments with similar compositions and features to those found in the unstable brandy appeared.
The amounts of sediment obtained were directly related to the decrease in Si concentration in solution. Consequently, it can be concluded that siliceous sediment in brandy originates from Si released during diatomite filtration
A Finite Element‑Based Methodology for the Thermo‑mechanical Analysis of Early Age Behavior in Concrete Structures
This paper presents a general procedure based on fracture mechanics models in order to analyze the level of cracking
and structural safety in reinforced concrete elements at early ages, depending on the stripping time. Our procedure
involves the development of a thermo-mechanical numerical model based on the finite element method that
accounts for the change in the mechanical properties of concrete with time. Moreover, fracture mechanisms are
analyzed by means of a material damage model, which is characterized via specific experimental results obtained for
standard specimens and notched beams under three-point bending testing. The loading conditions are both thermal
and mechanical, and are obtained from the hydration process for a given concrete dosage. The presented methodology
allows for the determination of the optimal stripping time, whereas it helps assessing the analysis of the cracking
and the stress states of the elements under consideration. A practical application, namely the analysis of a retaining
wall, is used to validate our methodology, showing its suitability in engineering practice.Ministerio de Economía y Competitividad BIA2016-75431-
Corrupción e inequidad en los servicios públicos en el Perú
Cada ciudadano peruano que tiene que realizar algún trámite en una dependencia estatal, sea nacional, regional o local, termina usualmente mortificado por las largas colas y tiempos de espera que hay que soportar, por las veces que hay que regresar a la misma institución para terminar con el trámite, por el trato descortés o simple maltrato de los funcionarios públicos y, en muchos casos, por el requerimiento de coimas para «agilizar» o hacer efectivo el servicio.
El Perú está viviendo una bonanza económica sin precedentes en su historia contemporánea, con tasas de crecimiento promedio anual superiores al 6% durante más de una década. En este contexto, los problemas que
más preocupan a la ciudadanía son la persistente desigualdad y pobreza, la corrupción en el Estado y la inseguridad ciudadana. Este estudio se ha concentrado en explorar la relación entre los dos primeros temas, empleando el uso de servicios públicos como eje central del análisis
Aplicación del autoconcepto al desarrollo de la marca personal. Análisis comparativo entre estudiantes internacionales
Individual personal brands have experienced a growing importance due to the massive use of new technologies. Everyone can benefit from the use of social networks to make a personal brand spread establishing a difference with the rest of the individuals. The interest to develop a personal brand is growing partly because of the high competitive employment market. Students in their last university years are especially interested in developing a personal brand. This study shows results obtained in a sample of students from Belgium and Spain. The objectives are to analyze self-concept as a valid tool to develop a personal brand and to establish possible differences in the self-concept levels of both nationalities. This article shows the results obtained in a study about personal brand and self-concept carried out in Belgium and Spain in May 2013.El auge de las nuevas tecnologías ha posibilitado la creación de la marca personal a nivel individual. Cualquier persona haciendo uso de las redes sociales puede difundir su imagen o marca a fin de construir una imagen diferenciada. El interés por el desarrollo de una marca personal consolidada se ha incrementado en la medida que resulta más difícil hacerse valer en un mercado de trabajo cada vez más competitivo. Los estudiantes a punto de entrar en el mercado laboral son unos sujetos especialmente interesados en el desarrollo de su marca personal. Así esta investigación utiliza como muestra a estudiantes de dos nacionalidades: españoles y belgas. El objetivo es doble, por un lado, presentar el autoconcepto como una herramienta adecuada al desarrollo de la marca personal y por otro, establecer posibles diferencias entre el nivel de autoconcepto de ambas nacionalidades. En este artículo se van presentar los resultados obtenidos en un estudio sobre autoconcepto y marca personal llevada a cabo en Bélgica y en España entre enero y mayo de 2013
La resiliencia en entrenadores de pádel adaptado
En el Deporte, la mayoría de los estudios sobre resiliencia se
han centrado en deportistas, siendo reducido el número de investigaciones
con entrenadores, sobre todo en el ámbito del deporte adaptado. Por ello,
los objetivos del trabajo son: describir las características de resiliencia de
entrenadores de Pádel Adaptado desarrollando baremos específicos para
muestra analizada; establecer posibles diferencias en los niveles de resiliencia
considerando variables personales y deportivas; establecer posibles relaciones
entre los niveles de resiliencia, la edad y experiencia; comparar los
niveles de resiliencia de la presente muestra con los resultados de estudios
precedentes y determinar los niveles de fiabilidad obtenidos con la escala
de resiliencia utilizada. La muestra estaba integrada por 111 entrenadores
de pádel adaptado, a los que se aplicó dos instrumentos: cuestionario sociodemográfico
para entrenadores de Pádel Adaptado (Ruiz, 2004; RuizBarquín,
De la Vega, De la Rocha y Batista, 2015a) y la adaptación al castellano
del cuestionario de Resiliencia (Ruiz, De la Vega, Poveda, Rosado y
Serpa, 2012). Los resultados señalan un alto porcentaje de entrenadores
con alta resiliencia (35.10%), mostrando niveles superiores a anteriores estudios
y adecuados niveles de fiabilidad. La ausencia de diferencias significativas
considerando las variables personales y deportivas, y las implicaciones
de prácticas derivadas de los resultados obtenidos, son discutidas.
Palabras clave: Resiliencia; entrenadores; pádel; deporte adaptadoIn Sport, most research on resilience is focused on athletes, with
quite a low amount on coaches, especially regarding adapted sport. Therefore,
the aims of this research are: to describe the resilience characteristics
of Adapted paddle coaches by developing specific scales for the sample
under study; to establish possible differences in the total resilience levels
considering different personal and sport variables; to establish possible relationships
between the resilience levels of Adapted Paddle Coaches and
the age and experience variables; to compare the resilience levels within the
current sample with results in previous studies; and to evaluate reliability
levels obtained with the resilience scale used. The sample comprised 111
adapted paddle coaches, to whom two questionnaires were given: a sociodemographic
one for adapted paddle coaches (Ruiz, 2004; Ruiz-Barquín,
De la Vega, De la Rocha y Batista, 2015a) and the Spanish version of resilience
(Ruiz, De la Vega, Poveda, Rosado & Serpa, 2012). The results conclude
that the sample group has a large percentage of coaches with high resilience
(35.10%), showing higher levels than those in previous studies, and
appropriate reliability levels. The absence of significant differences, taking
into account the personal and sport variables, and the implications of practices
deriving from the results obtained, are discussed in the articl
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