Microwave dielectric properties of MO -La2O3-TiO2 (M = Ca, Sr, Ba) ceramics

Single-phase polycrystalline ceramics in the MO-La2O3-Ti02 (M = Ca, Sr, Ba) system, such as cation-deficient hexagonal perovskites CaLa4Ti4O15, SrLa4Ti4O15, BaLa4Ti4O15, and Ca2La4Ti5O18 and the orthorhombic phases CaLa4Ti5O17 and CaLa8Ti9O31, were prepared through the solid-state ceramic route. The phases and structure of the ceramics were analyzed through x-ray diffraction and scanning electron microscopy. The microwave dielectric properties of the ceramics were studied using a network analyzer. The investigated ceramics show high Er in the range 42 to 54, high quality factors with Q x f in the range 16,222 to 50,215 GHz, and low Tf in the range -25 to +6 ppm3/°C. These high dielectric constant materials with high Q x f up to 50,215 GHz are suitable for applications where narrow bandwidth and extremely low insertion loss is necessary, especially at frequencies around 1.9 GHz

Surface electron properties and catalytic activity of Sr doped lanthana

The electron donating properties, surface acidity/basicity and catalytic activity of lanthana for various dopant concentrations of strontium are reported at two activation temperatures. The catalytic activity has been correlated with electron donating properties and surface acidity/basicity of the oxide.

Influence of Si, Sb and Sr Additions on the Microstructure, Mechanical Properties and Corrosion Behavior of AZ91 Magnesium Alloy

All the exciting work on developing new and better alloys has led older alloys, such as AZ9l , being abandoned by researchers. lt is believed that the full potential of AZ9l in automotive design has not been realized. Whatever works have been carried out on AZ9lalloy to improve its mechanical properties are insufficient in terms of its potential usage in auto industries. Due to the fact that AZ91 offers high room temperature mechanical properties and good castability, still this alloy is a primary choice for the auto component manufactures. Small improvement in its creep properties will have a huge impact in the transportation industries. Hence, in the present work, “Influence of Si, Sb and Sr Additions on the Microstructure, Mechanical Properties and Corrosion Behavior of AZ91 Magnesium Alloy”, an attempt has been made to improve the creep properties of AZ9l alloy through minor alloying elemental additions and to understand its strengthening mechanisms. The effect of alloying additions on the ageing and tensile properties of AZ9l is also studied. In addition to that, role of various intermetallics formed due to the alloying additions on the corrosion properties of AZ9l alloy is investigated.

Properties of Anisotropic Superconductors in SR Model

The present thesis deals with the theoretical investigations on the effect of anisotropy on various properties of magnetically doped superconductors described by fihiba — Rusinov model.Chapter 1 is introductory. It contains a brief account of the current status of theory of superconductivity. In’ chapter 2 we give the formulation of the problem. Chapter 2.1 gives the BCS theory. The effect of magnetic impurities in superconductors as described by A8 theory is given in chapter 2.2A and that described by SR model is discussed in chapter 2.28. Chapter 2.2c deals with Kondo effect. In chapter 2.3 the anisotropy problem is reviewed. Our calculations, results and discussions are given in chapter 3. Chapter 3.1 deals with Josephson tunnel effect. In chapter 3.2 the thermodynamic critical field H62 is described. Chtpter 3.3 deals with the density of states. The ultrasonic attenuation coefficient and ufitlear spin relaxation are given in chapter 3.4 and 3.5 respectively. In chapter 3.6 we give the upper critical field calculations and chapter 3.7 deals with the response function. The Kondo effect is given in chapter 3.8. In chapter 4 we give the sumary of our results

Colossal thermoelectric power in Gd-Sr manganites

Manganites belonging to the series Gd1−xSrxMnO3 (x=0.3, 0.4 and 0.5) were prepared by wet solid-state reaction and their thermoelectric power was evaluated. Thermoelectric power measurements revealed a peak value at ∼40 K. All the samples exhibited a colossal thermopower at ∼40K and in that Gd0.5Sr0.5MnO3 exhibited a maximum value of ∼35mV/K, which is the largest reported for these class of materials at this temperature. Temperaturedependent magnetisation measurements showed that the samples exhibit a phase transition from paramagnetic to spin-glass–like state at these temperatures. Plausible mechanisms responsible for the observed colossal thermoelectric power in Gd-Sr manganites are discussed

Solemne apertura del curso acad??mico 1995-96 : investidura de Doctor Honoris Causa del Excmo. Sr. D. Mario Vargas Llosa

Los discursos del acto central de la investidura son: Vargas Llosa: elogio y defensa de la escritura, de Victorino Polo y sobre el indigenismo en la literatura peruana del propio Vargas Llosa

Planteamientos futuros de la Facultad de Medicina de la Universidad de Murcia ante la convergencia europea en el año 2006 : discurso de recepción pública del Académico Numerario de la Real Academia de Medicina y Cirugía de Murcia Ilmo. Sr. D. Fernando Sánchez Gascón, leído el día 6 de junio de 2006 y contestado por el Académico Numerario de la Real Academia de Medicina y Cirugía de Murcia Ilmo. Sr. D. Guzmán Ortuño Pacheco.

La obra cuenta con el discurso de contestación del Académico de Número de la Real Academia de Medicina y Cirugía de Murcia D. Guzmán Ortuño Pacheco

La formación médica pregraduada, problemas y soluciones : discurso doctrinal, Exmo. Sr. D. Ciril Rozmán, Murcia, 28 de febrero de 2008.

Precede al título: Sesión extraordinaria y solemne de recepción de Académico de Honor.

Patronat: Entrevista al Sr. Manel Xifra, president del Patronat de l'EPS

El 17 de novembre de 2006 el Ple del Patronat de l’Escola Politècnica Superior va elegir el Sr. Manel Xifra president, en substitució del Sr. David Marca, que havia presidit el Patronat els últims dos mandats. Hem volgut, doncs, en aquest primer número de la revista de l’EPS, iniciar aquest apartat amb una entrevista al Sr. Manel Xifra, perquè ens doni una visió de la realitat actual del Patronat de l’Escola Politècnica Superior i del seu futur

Un cuestionario de personalidad The Jr.-Sr. High School Personality Questionaire Raymond B. Cattell.

Pretender adentrarnos en la prometedora realidad que ha supuesto en la psicología científica el método de análisis factorial. Pues, hasta ahora, el mundo psicológico español, está muy en contacto con las corrientes psicológicas comprensivas y clínica sin que tenga la conveniente abundancia de elementos psicométricos del método científico del análisis factorial. Por otro lado, la pretensión es contentarse con satisfacer una curiosidad científica por este autor y su obra, no muy conocidos en España. Seiscientos cuarenta y tres individuos estudiantes de Bachillerato; hombres y mujeres de una capital española. También, se aplicó a ciento ocho estudiantes universitarios post-graduados de diferentes carreras y edades. Test de Raymond B. Cattell, H.S.P.Q. (The Jr.-Sr. Hihg School Personality Questionaire). Cuestionario, cuadros, gráficas. Se constata a través de la elaboración de la estadística que apenas existen diferencias significativas entre la motivación francesa y la española.

Las historias del Sr. Mortela.

Se describe una experiencia de animación a la lectura y cuenta-cuentos mediante el empleo de imágenes extraídas de los cuentos, se acompañan de otros materiales (sonidos, vídeos) para conseguir motivar y hacer partícipes a los alumnos de la animación, que participe y juegue con las lecturas que se realizan, utilizando los medios informáticos y audiovisuales como apoyo.