{"id":84597,"date":"2018-03-10T00:08:55","date_gmt":"2018-03-10T00:08:55","guid":{"rendered":"https:\/\/www.deberes.net\/tesis\/sin-categoria\/estudio-termodinamico-de-cristales-tipo-perovskita-en-las-cercanias-del-punto-tricritico\/"},"modified":"2018-03-10T00:08:55","modified_gmt":"2018-03-10T00:08:55","slug":"estudio-termodinamico-de-cristales-tipo-perovskita-en-las-cercanias-del-punto-tricritico","status":"publish","type":"post","link":"https:\/\/www.deberes.net\/tesis\/fisica\/estudio-termodinamico-de-cristales-tipo-perovskita-en-las-cercanias-del-punto-tricritico\/","title":{"rendered":"\u00abestudio termodin\u00e1mico de cristales tipo perovskita en las cercanias del punto tricritico\u00bb"},"content":{"rendered":"<h2>Tesis doctoral de <strong> Francisco Javier Romero Landa <\/strong><\/h2>\n<p>Se ha realizado un estudio termodin\u00e1mico de la transici\u00f3n de fase ferroel\u00e1stica c\u00fabica-tetragonal de los cristales srtio3 y kmn1-x caxf3 mediante la medida de calor espec\u00edfico y calor latente usando la t\u00e9cnica de calorimetr\u00eda de conducci\u00f3n. Se ha desarrollado un nuevo m\u00e9todo que, comparando las medidas de calor espec\u00edfico y de an\u00e1lisis t\u00e9rmico diferencial realizadas con el mismo sistema, sobre la misma muestra y bajo las mismas condiciones t\u00e9rmicas, permite discriminar, en el cambio total de entalp\u00eda, las contribuciones del calor espec\u00edfico y del calor latente. En el estudio del kmnf3 se ha determinado por primera vez el calor latente como 0,129 jg 1 y se ha encontrado que la sustituci\u00f3n de mn por ca hace que la transici\u00f3n de fase cruce el punto tricr\u00edtico y se haga de segundo orden. Se ha encontrado que las medidas experimentales de calor espec\u00edfico, calor latente y deformaci\u00f3n espont\u00e1nea, proporcional al cuadrado del par\u00e1metro de orden, obtenidos en este conjunto de cristales pueden ser descritas adecuadamente mediante un potencial de landau 2-4-6 caracteristico de transiciones de fase pr\u00f3ximas a punto tricr\u00edtico,donde el coeficiente b,prefactor del termino q4,cambia de signo con la adici\u00f3n de ca. En el caso del srtio3, la comparaci\u00f3n del exceso de entrop\u00eda con medidas experimentales del cuadrado del par\u00e1metro de orden ha puesto de manifiesto que la transici\u00f3n puede ser descrita mediante la teor\u00eda de landau para el caso de que est\u00e1 se encuentre pr\u00f3xima al punto tricritico y se ha restringido un posible comportamiento cr\u00edtico a un intervalo de temperaturas inferior a 0.1 k por debajo de la transici\u00f3n.<\/p>\n<p>&nbsp;<\/p>\n<h3>Datos acad\u00e9micos de la tesis doctoral \u00ab<strong>\u00abestudio termodin\u00e1mico de cristales tipo perovskita en las cercanias del punto tricritico\u00bb<\/strong>\u00ab<\/h3>\n<ul>\n<li><strong>T\u00edtulo de la tesis:<\/strong>\u00a0 \u00abestudio termodin\u00e1mico de cristales tipo perovskita en las cercanias del punto tricritico\u00bb <\/li>\n<li><strong>Autor:<\/strong>\u00a0 Francisco Javier Romero Landa <\/li>\n<li><strong>Universidad:<\/strong>\u00a0 Sevilla<\/li>\n<li><strong>Fecha de lectura de la tesis:<\/strong>\u00a0 19\/05\/2000<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<h3>Direcci\u00f3n y tribunal<\/h3>\n<ul>\n<li><strong>Director de la tesis<\/strong>\n<ul>\n<li>Jaime Del Cerro Gonz\u00e1lez<\/li>\n<\/ul>\n<\/li>\n<li><strong>Tribunal<\/strong>\n<ul>\n<li>Presidente del tribunal: manuel Zamora carranza <\/li>\n<li> Gonzalo gonzalez julio a. (vocal)<\/li>\n<li>ekhard Salje (vocal)<\/li>\n<li>ramon Burriel laos (vocal)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tesis doctoral de Francisco Javier Romero Landa Se ha realizado un estudio termodin\u00e1mico de la transici\u00f3n de fase ferroel\u00e1stica c\u00fabica-tetragonal [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[199,10715,2793],"tags":[178621,178619,15209,178620,108286,178622],"class_list":["post-84597","post","type-post","status-publish","format-standard","hentry","category-fisica","category-sevilla","category-termodinamica","tag-ekhard-salje","tag-francisco-javier-romero-landa","tag-gonzalo-gonzalez-julio-a","tag-jaime-del-cerro-gonzalez","tag-manuel-zamora-carranza","tag-ramon-burriel-laos"],"_links":{"self":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/84597","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/comments?post=84597"}],"version-history":[{"count":0,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/84597\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/media?parent=84597"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/categories?post=84597"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/tags?post=84597"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}