Towards Realization of Magnetocaloric and Magnetoelectric Applications based on Bulk and Thin film forms of Sodium substituted Lanthanum Manganites

The present thesis work focuses on hole doped lanthanum manganites and their thin film forms. Hole doped lanthanum manganites with higher substitutions of sodium are seldom reported in literature. Such high sodium substituted lanthanum manganites are synthesized and a detailed investigation on their structural and magnetic properties is carried out. Magnetic nature of these materials near room temperature is investigated explicitly. Magneto caloric application potential of these materials are also investigated. After a thorough investigation of the bulk samples, thin films of the bulk counterparts are also investigated. A magnetoelectric composite with ferroelectric and ferromagnetic components is developed using pulsed laser deposition and the variation in the magnetic and electric properties are investigated. It is established that such a composite could be realized as a potential field effect device. The central theme of this thesis is also on manganites and is with the twin objectives of a material study leading to the demonstration of a device. This is taken up for investigation. Sincere efforts are made to synthesize phase pure compounds. Their structural evaluation, compositional verification and evaluation of ferroelectric and ferromagnetic properties are also taken up. Thus the focus of this investigation is related to the investigation of a magnetoelectric and magnetocaloric application potentials of doped lanthanum manganites with sodium substitution. Bulk samples of sodium substituted lanthanum manganites. Bulk samples of sodium substituted lanthanum manganites with Na substitution ranging from 50 percent to 90 percent were synthesized using a modified citrate gel method and were found to be orthorhombic in structure belonging to a pbnm spacegroup. The variation in lattice parameters and unit cell volume with sodium concentration were also dealt with. Magnetic measurements revealed that magnetization decreased with increase in sodium concentrations.

Model Calculations and Implementation of Filters and Hybrid Green VCSELs based on Optical Thin Film Stacks

This work introduced the novel conception of complex coupled hybrid VCSELs for the first time. Alternating organic and inorganic layers in the lasers provide periodic variation of refractive index and optical gain, which enable single mode operation and low threshold of the VCSELs. Model calculations revealed great reduction of the lasing threshold with factors over 30, in comparison with the existing micro-cavity lasers. Tunable green VCSEL has been also designed, implemented and analyzed taking advantage of the broad photoluminescence spectra of the organics. Free standing optical thin films without compressive stress are technologically implemented. Multiple membrane stacks with air gap in between have been fabricated for the implementation of complex coupled VCSEL structures. Complex coupled hybrid VCSEL is a very promising approach to fill the gaps in the green spectral range of the semiconductor lasers.

Oblique Angle Deposition of Germanium Film on Silicon Substrate

The effect of flux angle, substrate temperature and deposition rate on obliquely deposited germanium (Ge) films has been investigated. By carrying out deposition with the vapor flux inclined at 87° to the substrate normal at substrate temperatures of 250°C or 300°C, it may be possible to obtain isolated Ge nanowires. The Ge nanowires are crystalline as shown by Raman Spectroscopy.

Poly-Si₁₋xGex Film Growth for Ni Germanosilicided Metal Gate

Scaling down of the CMOS technology requires thinner gate dielectric to maintain high performance. However, due to the depletion of poly-Si gate, it is difficult to reduce the gate thickness further especially for sub-65 nm CMOS generation. Fully silicidation metal gate (FUSI) is one of the most promising solutions. Furthermore, FUSI metal gate reduces gate-line sheet resistance, prevents boron penetration to channels, and has good process compatibility with high-k gate dielectric. Poly-SiGe gate technology is another solution because of its enhancement of boron activation and compatibility with the conventional CMOS process. Combination of these two technologies for the formation of fully germanosilicided metal gate makes the approach very attractive. In this paper, the deposition of undoped Poly-Si₁₋xGex (0 < x < 30% ) films onto SiO₂ in a low pressure chemical vapor deposition (LPCVD) system is described. Detailed growth conditions and the characterization of the grown films are presented.

Plasma polymerization of C[subscript 4]F[subscript 8] thin film on high aspect ratio silicon molds

High aspect ratio polymeric micro-patterns are ubiquitous in many fields ranging from sensors, actuators, optics, fluidics and medical. Second generation PDMS molds are replicated against first generation silicon molds created by deep reactive ion etching. In order to ensure successful demolding, the silicon molds are coated with a thin layer of C[subscript 4]F[subscript 8] plasma polymer to reduce the adhesion force. Peel force and demolding status are used to determine if delamination is successful. Response surface method is employed to provide insights on how changes in coil power, passivating time and gas flow conditions affect plasma polymerization of C[subscript 4]F[subscript 8].

Data Protection Act links to film, slides, quesions; overview notes

Published on Jun 7, 2012 by icocomms This ICO training video helps answer questions about the Data Protection Act, its impact on the working environment and how to handle and protect people's information. (Produced by Central Office of Information, Crown Copyright 2006)

The Phenomenology of the Political: Cavell on Film

A lengthy defense of Cavell on film and politics in response to an article by Joshua Dienstag

Film, TV and music : multi-level photocopiable activities for teenagers.

Este recurso para el profesor contiene actividades que abarcan temas de interés para los jóvenes como el cine, la música y la televisión. Proporciona material didáctico adicional, que puede fotocopiarse, para los niveles elemental, intermedio y avanzado.

Proyecto curricular del área de Inglés : film workshop.

Material publicado por el Departamento de Educación, Universidades e Investigación del Gobierno Vasco. Se trata de materiales curriculares que pretenden servir para la formación del profesorado y que ejemplifican y marcan pautas para el trabajo según los nuevos planteamientos curriculares de la LOGSE. Los que aquí se presentan pretenden aumentar el interés de los alumnos por la lengua y mostrar cómo el mundo del espectáculo puede servir de base para el estudio de la cultura y civilización de otros países. Ofrecen un conjunto de actividades que permiten la realización de un trabajo interdisciplinar, pudiendo implicar a varios seminarios (Historia, Lengua, Filosofía, etc.), y adoptan un enfoque comunicativo, primando la utilización de recursos auténticos: audiovisuales (películas), textos escritos (fuentes de información, literarios, etc.) y musicales (canciones). En resumen, los contenidos del documento pueden enmarcarse: - dentro del área; - dentro de una línea transversal (Educación en Medios de Comunicación Social); y - bajo un planteamiento interdisciplinar.

Cómo limpiarse las gafas : fragmento de una carta : sobre el análisis del film.

Visión de cómo se ha de analizar una película, utilizando distintos instrumentos para comentar cada film. En primer lugar, se describen los distintos tipos de análisis existentes, y después, se exponen varios ejemplos de análisis, con distintos instrumentos cada uno, de manera que respondan a las necesidades que plantee cada film. Además, ha de tenerse en cuenta el ámbito de aplicación de cada procedimiento de análisis.

El apagón analógico : el British Film Institute y la educación en los tres últimos decenios.

Resumen basado en el de la revista. - El artículo pertenece a una sección monográfica de la revista dedicada a Lenguajes fílmicos en la memoria colectiva de Europa

Film scoring.

Resumen tomado de la publicación. - El artículo pertenece a una sección de la revista dedicada a: El aula de música y las competencias básicas

Some of my favourite film stars : una experiencia de aula utilizando Internet.

Se describe la experiencia llevada a cabo con alumnos de primero de ESO en la asignatura de Inglés y que consistía en la búsqueda de un personaje de su interés en la página web: www.biography.com y en analizar su biografía a través de diversas actividades utilizando el idioma inglés. Los objetivos del trabajo son: desarrollar la capacidad lectora de los alumnos en inglés aún cuado no entiendan todo, leer para obtener la información específica, aprender a intuir el significado de palabras desconocidas por el contexto, practicar el vocabulario y las estructuras estudiadas, conseguir que los alumnos adquieran confianza a la hora de enfrentarse a páginas web en inglés y capacitar a los alumnos para que realicen búsquedas en Internet de material en inglés.