{"id":718,"date":"2015-06-12T13:58:07","date_gmt":"2015-06-12T11:58:07","guid":{"rendered":"https:\/\/sim.utcluj.ro\/wp\/?p=718"},"modified":"2015-06-24T08:51:00","modified_gmt":"2015-06-24T06:51:00","slug":"materialele-ceramice","status":"publish","type":"post","link":"https:\/\/sim.utcluj.ro\/materialele-ceramice\/","title":{"rendered":"MATERIALELE CERAMICE"},"content":{"rendered":"<p>\u00cen muzeele lumii se g\u0103sesc obiecte vechi de mii de ani realizate din ceramic\u0103 care restabilesc o punte c\u0103tre culturi de mult apuse. Privind aceste obiecte valoroase, ne imagin\u0103m artistul care le-a creat cu at\u00e2ta timp \u00een urm\u0103 \u015fi admir\u0103m sim\u0163ul artistic al celui care le-a dat via\u0163\u0103. De\u015fi s-au a\u015fternut mii de ani din momentul \u00een care m\u00e2inile iscusite au desenat figuri \u015fi simboluri pe aceste obiecte extraordinar de frumoase, avem senza\u0163ia c\u0103 suntem purta\u0163i \u00een timp \u015fi revedem acele clipe \u00een care lumina dimine\u0163ii au sc\u0103ldat pentru prima dat\u0103 aceste obiecte minunate. Revenim brusc la realitate, \u00eentr-o er\u0103 a computerelor \u015fi telefoanelor celulare, iar mileniile care ne separ\u0103 \u00een timp par a fi comprimate \u00eentr-o secund\u0103. Admir\u0103m motivele geometrice din trecut ce inspir\u0103 prezentul \u015fi ne sim\u0163im m\u00e2ndri, str\u0103mo\u015fii no\u015ftri sunt arti\u015ftii care ne-au l\u0103sat mo\u015ftenire un trecut at\u00e2t de bogat.<\/p>\n<p><iframe src=\"https:\/\/www.youtube.com\/embed\/FQN9Z6WIw0I\" width=\"420\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Materialele ceramice de\u015fi cunoscute de-at\u00e2ta timp nu \u015fi-au epuizat secretele. Industria electronic\u0103, IT, auto sau cea spa\u0163ial\u0103 beneficiaz\u0103 din plin de propriet\u0103\u0163ile neb\u0103nuite ale acestora. Materialele ceramice au caracteristici diferite fa\u0163\u0103 de cele metalice sau polimerice. Pot avea structur\u0103 amorf\u0103, cristalin\u0103 sau o combina\u0163ie a acestora. Prezint\u0103 duritate ridicat\u0103, ceea ce le confer\u0103 \u015fi fragilitate \u015fi sunt inerte din punct de vedere chimic. Cele mai cunoscute aplica\u0163ii ale materialelor ceramice sunt legate direct de istoria noastr\u0103, <a href=\"http:\/\/www.bbc.com\/news\/science-environment-18602281\">cele mai vechi fragmente de ceramic\u0103<\/a> dateaz\u0103 de peste 20.000 ani.<\/p>\n<p><a href=\"https:\/\/sim.utcluj.ro\/wp\/wp-content\/uploads\/2015\/06\/TokamchiCityMuseum1.jpg\"><img fetchpriority=\"high\" decoding=\"async\" class=\"alignleft size-full wp-image-721\" src=\"https:\/\/sim.utcluj.ro\/wp\/wp-content\/uploads\/2015\/06\/TokamchiCityMuseum1.jpg\" alt=\"TokamchiCityMuseum\" width=\"691\" height=\"404\" srcset=\"https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/TokamchiCityMuseum1.jpg 691w, https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/TokamchiCityMuseum1-300x175.jpg 300w, https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/TokamchiCityMuseum1-600x351.jpg 600w\" sizes=\"(max-width: 691px) 100vw, 691px\" \/><\/a><\/p>\n<p><em>\u00a0Left: a reconstructed Incipient Jomon vessel from Torihama, Japan (Wakasa History and Folklore Museum). Right: an Incipient Jomon pot from Kubodera-minami, Niigata Prefecture, Japan, about 15,000 years old (Tokamchi City Museum).<\/em><\/p>\n<p>Materialele ceramice au permis celor mai vechi culturi s\u0103 lase mo\u015ftenire dovezi despre felul lor de via\u0163\u0103, cultura \u015fi tradi\u0163iile acestora. Un mare savant german, Harald Haarmann, specialist \u00een istorie cultural\u0103, arheomitologie, istoria scrisului, evolu\u021bia limbii \u0219i istoria religiilor, autor a 40 de c\u0103r\u021bi traduse \u00een diverse limbi de circula\u021bie interna\u021bional\u0103, editor \u0219i co-editor a 20 de antologii, face o declara\u021bie de mare importan\u021b\u0103 pentru noi, rezultat al cercet\u0103rilor sale. El spune c\u0103 cea mai veche scriere din lume e cea de la T\u0103rt\u0103ria, Rom\u00e2nia \u0219i c\u0103 Civiliza\u021bia Danubian\u0103 este prima mare civiliza\u021bie din istorie, mai veche cu mii de ani dec\u00e2t cea sumerian\u0103 considerat\u0103 \u00eenc\u0103 leag\u0103nul civiliza\u021biei.<\/p>\n<p><iframe src=\"https:\/\/www.youtube.com\/embed\/EheI4gH_nCI\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>\u00cen prezent materialele ceramice sunt utilizate \u00een diverse domenii, unele mai pu\u0163in cunoscute de publicul larg. De exemplu, materialele ceramice sunt utilizate \u00een electronic\u0103 deoarece \u00een func\u0163ie de compozi\u0163ia chimic\u0103 \u015fi temperatur\u0103, acestea pot fi semiconductoare, supraconductoare, feroelectrice sau izolatoare. De la corpul bujiilor, fibrele optice, lag\u0103rele autolubrefiante, discurile de fr\u00e2n\u0103 p\u00e2n\u0103 la pl\u0103cu\u0163ele termoizolante cu care sunt placate navetele spa\u0163iale, materialele ceramice au contribuit enorm la dezvoltarea societ\u0103\u0163ii moderne.<\/p>\n<p><a href=\"https:\/\/sim.utcluj.ro\/wp\/wp-content\/uploads\/2015\/06\/CeramicTiles1.jpg\"><img decoding=\"async\" class=\"alignleft size-full wp-image-723\" src=\"https:\/\/sim.utcluj.ro\/wp\/wp-content\/uploads\/2015\/06\/CeramicTiles1.jpg\" alt=\"CeramicTiles\" width=\"800\" height=\"535\" srcset=\"https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/CeramicTiles1.jpg 800w, https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/CeramicTiles1-300x201.jpg 300w, https:\/\/sim.utcluj.ro\/wp-content\/uploads\/2015\/06\/CeramicTiles1-600x401.jpg 600w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/a><\/p>\n<p>Materialele ceramice sunt o promisiune \u015fi pentru viitor. Superconductorii sunt materiale care nu prezint\u0103 rezisten\u0163\u0103 electric\u0103 la trecerea curentului. O alt\u0103 proprietate interesant\u0103 este capabilitatea de a respinge c\u00e2mpurile magnetice \u015fi de a interac\u0163iona cu acestea \u00eentr-un mod unic care permite pozi\u0163ionarea \u015fi blocarea materialului supraconductor \u00een raport cu liniile de c\u00e2mp magnetic.<\/p>\n<p>Supraconductibilitatea este un fenomen \u00een care rezisten\u021ba electric\u0103 a unui material conductor devine zero, dac\u0103 temperatura sa este mai mic\u0103 dec\u00e2t o anumit\u0103 valoare specific\u0103 materialului, numit\u0103 temperatur\u0103 critic\u0103. \u00cen cazul materialelor ceramice cercetate p\u00e2n\u0103 acum, temperatura critic\u0103 este apropiat\u0103 de temperatura de fierbere a azotului lichid, cca. -196\u00b0C. Totodat\u0103, se fac cercet\u0103ri pentru a ob\u0163ine fenomenul de supraconductibilitate la temperaturi apropiate de cea a camerei, fapt ce va deschide noi orizonturi \u015fi aplica\u0163ii pentru aceste materiale.<\/p>\n<p>Fenomenul de levitare magnetic\u0103 va sta la baza noilor mijloace de transport, asemenea trenurilor Maglev. Mai jos, pute\u0163i s\u0103 urm\u0103ri\u0163i un material video despre materialele supraconductoare.<\/p>\n<p><iframe src=\"https:\/\/embed-ssl.ted.com\/talks\/lang\/ro\/boaz_almog_levitates_a_superconductor.html\" width=\"640\" height=\"360\" frameborder=\"0\" scrolling=\"no\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Material realizat de S.L.dr.ing. Bodea Marius<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00cen muzeele lumii se g\u0103sesc obiecte vechi de mii de ani realizate din ceramic\u0103 care restabilesc o punte c\u0103tre culturi [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"gallery","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","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":"","ast-disable-related-posts":"","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-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-opacity":"","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-opacity":"","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-opacity":"","overlay-gradient":""}},"ast-content-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-opacity":"","overlay-gradient":""},"tablet":{"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-opacity":"","overlay-gradient":""},"mobile":{"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-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[24,25,23],"class_list":["post-718","post","type-post","status-publish","format-gallery","hentry","category-materiale","tag-ceramice","tag-istorie","tag-supraconductori","post_format-post-format-gallery"],"_links":{"self":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/718","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/comments?post=718"}],"version-history":[{"count":7,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/718\/revisions"}],"predecessor-version":[{"id":753,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/718\/revisions\/753"}],"wp:attachment":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/media?parent=718"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/categories?post=718"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/tags?post=718"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}