Científics universals, III. 'Científicos universales, III'.

Resumen basado en el autor en catalán

Compartir planeta, III : el relleu de generacions. 'Compartir planeta, III : el relevo de las generaciones'.

Resumen basado en el del autor en catalán

Compartir planeta, III : el relevo de las generaciones.

Resumen basado en el del autor

Flash ciencias, III.

Resumen basado en el del autor

Com viuen els animals, III. 'Como viven los animales, III'

Resumen del autor en catal??n

Como viven los animales, III.

Resumen del autor

III Certamen Diseño de Programas Informáticos Educativos : 2002.

El CD-ROM recoge los cuatro trabajos premiados y las menciones en el Tercer Certamen de Premios a Programas Informáticos Educativos de 2002, organizado por el Área de Formación del Profesorado de la Consejería de Educación. Los programas premiados son El sistema de vistas, programa de aprendizaje del dibujo de figuras geométricas; Gramática visual del Español, donde se estudian y trabajan los principios de la Gramática Española mediante diversas oraciones; Programa para el desarrollo de la atención y progresos asociados, aplicación formada por gran variedad de actividades destinadas a Educación Infantil y Primaria; y Aulas virtuales de Biología, sitio web que presenta de forma atractiva algunos contenidos de Ciencias Naturales sobre Botánica y Zoología. Los programas con menciones son Creación de materiales curriculares multimedia, CalculoM y el Proceso de creación en el diseño. Cada programa contiene una introducción con el autor o autores, la explicación del contenido y el nivel educativo al que está destinado.

La música civil en Murcia de Felipe V a Carlos III : del barroco cambio dinástico al esplendor de la Ilustración.

Los objetivos son: llegar a conocer el desarrollo y particularidades de la música civil, y actividades en torno a ella, en la ciudad de Murcia durante el periodo del cambio dinástico y la consolidación de la dinastía borbónica. Poner en relación dichas actividades musicales con el resto de manifestaciones artísticas del periodo. Comparar el nivel y calidad de estas actividades con las del entorno geográfico cercano, así como con el referente de la Corte. Definir los criterios socio-económicos, políticos y estético-culturales que condicionaron la materialización de todas estas actividades musicales, con el fin de proporcionar los elementos necesarios que definan la transición entre el Barroco y el Clasicismo. La metodología seguida se centra principalmente en el proceso de búsqueda de información y documentación, en bibliotecas y archivos, en la forma de organizar dichas fuentes de información para su posterior consulta y el sistema de referencias seguido para citar los documentos. Una vez concluido el análisis de la documentación de archivo y de los textos de carácter estético seleccionados, se confirman los objetivos iniciales de la tesis, demostrando que las hipótesis esbozadas se han visto refrendadas en su totalidad. Así, se afirma que la ausencia de estudios sobre la música en el ámbito civil murciano en el periodo estudiado, que podía inducir a la creencia de que ésta no existía o era apenas relevante no se corresponde con la realidad hallada en la documentación de archivo. La actividad musical fue amplia y variada, similar a la desarrollada en otras ciudades del entorno geográfico (Alicante, Orihuela o Cartagena) y, en determinadas ocasiones, marcada directamente por la influencia de la Corte.

Métodos matemáticos de la Física III.

Resumen tomado de la publicación

Poly[(2,2 '-bipyridine-kappa N-2,N ')-(mu(2)-dihydrogen phosphato-kappa O-2 : O ')-(mu(2)-hydrogen phosphato-kappa O-2 : O ')-aluminium(III)], Al(2,2 '/bipy)-(HPO4)(H2PO4), a layered inorganic - organic hybrid material

The title compound, [Al(HPO4)(H2PO4)(C10H8N2)]n, consists of AlO4N2 octahedra vertex-linked to H2PO4 and HPO4 tetrahedra to form layers based on a (4,12)- net. The layers stack in an AAA fashion, held in place by pi-pi interactions between 2,2 '-bipyridine molecules coordinated to Al atoms in adjacent layers.

Theoretical investigation of Hf and Zr defects in c-Ge

The introduction of high-permittivity gate dielectric materials into complementary metal oxide semiconductor technology has reopened the interest in Ge as a channel material mainly due to its high hole mobility. Since HfO(2) and ZrO(2) are two of the most promising dielectric candidates, it is important to investigate if Hf and Zr may diffuse into the Ge channel. Therefore, using ab initio density functional theory calculations, we have studied substitutional and interstitial Hf and Zr impurities in c-Ge, looking for neutral defects. We find that (i) substitutional Zr and Hf defects are energetically more favorable than interstitial defects; (ii) under oxygen-rich conditions, neither Zr nor Hf migration towards the channel is likely to occur; (iii) either under Hf- or Zr-rich conditions it is very likely, particularly for Zr, that defects will be incorporated in the channel.

New hydrazine sensors based on electropolymerized meso-tetra (4-sulphonatephenyl)porphyrinate manganese (III)/silver nanomaterial

A new electrocatalytic active porphyrin nanocomposite material was obtained by electropolymerization of meso-tetra(4-sulphonatephenyl) porphyrinate manganese(III) complex (MnTPPS) in alkaline solutions containing sub-micromolar concentrations of silver chloride. The modified glassy carbon electrodes efficiently oxidize hydrazine at 10 mV versus Ag/AgCl, dramatically decreasing the overpotential of conventional carbon electrodes. The analytical characteristics of this amperometric sensor coupled with batch injection analysis (BIA) technique were explored. Wide linear dynamic range (2.5 x 10(-7) to 2.5 x 10(-4) mol L-1), good repeatability (R.S.D. = 0.84%, n = 30) and low detection (3.1 x 10(-8) mol L-1) and quantification (1.0 x 10(-7) mol L-1) limits, as well as very fast sampling frequency (60 determinations per hour) were achieved. (c) 2007 Elsevier B.V. All rights reserved.

Polypyrrole-coated electrospun nanofibre membranes for recovery of Au(III) from aqueous solution

In this paper, for the first time, polypyrrole-coated electrospun nanofibre mats have been used as separation membranes to electrolessly recover Au from aqueous [Au(III)Cl₄]− solutions, based on a continuous-flow membrane separation process. With a [Au(III)Cl₄]− solution passing through the nanofibre membrane, the Au(III) ions were converted into elemental Au. The gold recovered was deposited on the nanofibre membranes in the form of Au particles, as confirmed by EDX and XPS measurements. It has been found that the polypyrrole-coated electrospun nanofibres are good candidate membrane material for the recovery of Au, and the recovery efficiency is affected by the membrane thickness, the permeate flux rate and the initial [Au(III)Cl₄]− concentration.

Exposure to As(III) and As(V) changes the Ca²⁺-activation properties of the two major fibre types from the chelae of the freshwater crustacean Cherax destructor

Arsenic is a known carcinogen found in the soil in gold mining regions at concentrations thousands of times greater than gold. Mining releases arsenic into the environment and surrounding water bodies. The main chemical forms of arsenic found in the environment are inorganic arsenite (As(III)) and arsenate (As(V)). Yabbies (Cherax destructor) accumulate arsenic at levels comparable to those in the sediment of their environment but the effect on their physiological function is not known. The effects of arsenic exposure (10 ppm sodium arsenite, AsNaO2 - 5.7 ppm As(III)) and 10 ppm arsenic acid, Na2HAsO4·7H2O - 2.6 ppm As(V)) for 40 days on the contractile function of the two major fibre types from the chelae were determined. After exposure, individual fibres were isolated from the chela, "skinned" (membrane removed) and attached to the force recording apparatus. Contraction was induced in solutions containing increasing [Ca(2+)] until a maximum Ca(2+)-activation was obtained. Submaximal force responses were plotted as a percentage of the maximum Ca(2+)-activated force. As(V) exposure resulted in lower levels of calcium required for activation than As(III) indicating an increased sensitivity to Ca(2+) after long term exposure to arsenate compared to arsenite. Myosin heavy chain and tropomyosin content in individual fibres was also decreased as a result of arsenic exposure. Single fibres exposed to As(V) produced significantly more force than muscle fibres from control animals. Long-term exposure of yabbies to arsenic alters the contractile function of the two major fibre types in the chelae.

Aplicação, em pré-colheita, de dessecante em duas cultivares de soja (Glycine max (L. ) Merril) III - Efeitos sobre a composição química (proteína, óleo e cinzas) e resíduos nas sementes

A aplicação pré-colheita do dessecante paraquat, quando real izada a partir das primeiras épocas (75 e 72 dias após o início do florescimento, para a Santa Rosa e IAC-2, respectivamente) não modificaram os teores com que ocorreram normalmente, proteína, extrato etéreo e cinzas nos grãos. As análises do resíduo de paraquat nos grãos colhidos, mostram claramente que não se deve recomendar tal prática às lavouras de soja, cujo objetivo final seja o fornecimento de grãos para a alimentação humana e animal. Entretanto pode ser indicada, sem maiores restrições, àquelas cuja finalidade é a produção de sementes comerciais.