1,576 research outputs found
Noticias de Nuestra Señora de Castroboda, patrona de la villa de Maderuelo (Segovia)
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201
Eclecticismo y diversidad en la geografía del crimen y la delincuencia en el cambio de siglo
This paper passes overhaul to the thematic ones that there is boarded the crime and delinquency geography. All themes are analyzed from epistemological perspectives.El artículo pasa revisión a las diferentes temáticas que ha abordado la geografía del crimen y la delincuencia desde su nacimiento en el último cuarto del siglo XX, hasta la actualidad. Dichas temáticas se analizan desde el contexto de sus perspectivas epistemológicas
Escuela cartografica de criminología británica: antecedentes de la Geografía del crimen.
Sin resume
Numerical method for analysis of the correlation between ferrofluid optical transmission and its intrinsic properties
A numerical method to simulate the ferrofluid particle distribution evolution is presented. Also, the optical transmission of the distributions obtained is calculated by two numerical methods. The first one consists on a numerical propagation of an electromagnetic wave through the sample. The second one analyzes the aggregates’ mean length to obtain the optical transmission through a mixture law. As an illustration of the possibilities of the method developed, it is applied to analyze how ferrofluid optical transmission changes after magnetic field application depend on intrinsic properties of the colloid such as its nanoparticle concentration and surfactant repulsion represented by means of the final distances between consecutive particles forming chains. Changes in the attenuation factor of these samples show the trends expected from the Literature
Analysis of the optical transmission of a ferrofluid by an electromagnetic mixture law
Evolution of the optical transmission of a ferrofluid after magnetic field commutation is analyzed by means of an approach based on the so-called mixture laws: expressions which predict the effective permittivity of heterogeneous media as a function of their constituents' permittivities, their proportions and the way they are arranged. In particular, this work is based on a law proposed by Sihvola and Kong for the effective permittivity of a host substance with ellipsoidal inclusions. Ferrofluids are peculiar examples of this kind of media: with the solvent as host, the inclusions are nanoparticle agglomerates whose shapes become modified by magnetic field exposure. In this work, experimental optical transmission of a ferrofluid is compared with predictions based on Sihvola and Kong''s law. A remarkable coincidence is obtained both in the absence of magnetic field, without using any fitting parameter, and in the presence of magnetic field, employing the inclusions' average ellipticity as the fitting parameter. The results obtained for time dependent optical transmission of a ferrofluid after magnetic field switch on or off allow one to estimate how the average shape of the agglomerates evolves over time. On the other hand, mixture laws are proven to be an interesting alternative to scattering concepts to model the optical transmission changes experienced by ferrofluids once they are exposed to magnetic fields
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