Prabhjot Singh

O xido de zinco um composto inorg nico com a f rmula ZnO. Apresenta-se normalmente como um p branco, quase insol vel em gua. O p amplamente utilizado como aditivo em numerosos materiais e produtos, incluindo pl sticos, cer mica, vidro, cimento, borracha (por exemplo, pneus de autom veis), lubrificantes, tintas, pomadas, adesivos, vedantes, pigmentos, alimentos (fonte de nutrientes de Zn), pilhas, ferrites, retardadores de fogo, fitas de primeiros socorros, etc. O ZnO est presente na crosta terrestre sob a forma do mineral zincite; no entanto, a maior parte do ZnO utilizado comercialmente produzido sinteticamente. Na ci ncia dos materiais, o ZnO frequentemente designado por semicondutor II-VI, uma vez que o zinco e o oxig nio pertencem ao segundo e sexto grupos da tabela peri dica, respetivamente. Este semicondutor tem v rias propriedades favor veis: boa transpar ncia, elevada mobilidade de electr es, grande intervalo de banda, forte luminesc ncia temperatura ambiente, etc. Estas propriedades j s o utilizadas em aplica es emergentes para el ctrodos transparentes em ecr s de cristais l quidos e em janelas que poupam energia ou protegem do calor, bem como em aplica es electr nicas de ZnO como trans stores de pel cula fina e d odos emissores de luz.

Tlenek cynku jest związkiem nieorganicznym o wzorze ZnO. Zwykle występuje w postaci bialego proszku, prawie nierozpuszczalnego w wodzie. Proszek ten jest szeroko stosowany jako dodatek do wielu material w i produkt w, w tym tworzyw sztucznych, ceramiki, szkla, cementu, gumy (np. opon samochodowych), smar w, farb, maści, klej w, uszczelniaczy, pigment w, żywności (źr dlo skladnik w odżywczych Zn), baterii, ferryt w, środk w zmniejszających palnośc, taśm pierwszej pomocy itp. ZnO występuje w skorupie ziemskiej jako mineral cynkit; jednak większośc ZnO wykorzystywanego komercyjnie jest produkowana syntetycznie. W materialoznawstwie ZnO jest często nazywany p lprzewodnikiem II-VI, ponieważ cynk i tlen należą odpowiednio do drugiej i sz stej grupy ukladu okresowego. Ten p lprzewodnik ma kilka korzystnych wlaściwości: dobrą przezroczystośc, wysoką ruchliwośc elektron w, szeroką przerwę pasmową, silną luminescencję w temperaturze pokojowej itp. Wlaściwości te są już wykorzystywane w nowych zastosowaniach przezroczystych elektrod w wyświetlaczach cieklokrystalicznych oraz w energooszczędnych lub chroniących przed cieplem oknach, a także w elektronicznych zastosowaniach ZnO jako tranzystor w cienkowarstwowych i diod elektroluminescencyjnych

L'ossido di zinco un composto inorganico con formula ZnO. Si presenta solitamente come una polvere bianca, quasi insolubile in acqua. La polvere ampiamente utilizzata come additivo in numerosi materiali e prodotti, tra cui plastica, ceramica, vetro, cemento, gomma (ad esempio, pneumatici per auto), lubrificanti, vernici, unguenti, adesivi, sigillanti, pigmenti, alimenti (fonte di nutrienti Zn), batterie, ferriti, ritardanti di fiamma, nastri di pronto soccorso, ecc. Lo ZnO presente nella crosta terrestre sotto forma di zincite; tuttavia, la maggior parte dello ZnO utilizzato in commercio prodotto sinteticamente. Nella scienza dei materiali, lo ZnO spesso chiamato semiconduttore II-VI perch lo zinco e l'ossigeno appartengono rispettivamente al 2 e al 6 gruppo della tavola periodica. Questo semiconduttore ha diverse propriet favorevoli: buona trasparenza, elevata mobilit degli elettroni, ampio band gap, forte luminescenza a temperatura ambiente, ecc. Queste propriet sono gi sfruttate nelle applicazioni emergenti di elettrodi trasparenti negli schermi a cristalli liquidi e nelle finestre a risparmio energetico o a protezione del calore, nonch nelle applicazioni elettroniche dello ZnO come transistor a film sottile e diodi a emissione luminosa.

L'oxyde de zinc est un compos inorganique dont la formule est ZnO. Il se pr sente g n ralement sous la forme d'une poudre blanche, presque insoluble dans l'eau. Cette poudre est largement utilis e comme additif dans de nombreux mat riaux et produits, notamment les plastiques, les c ramiques, le verre, le ciment, le caoutchouc (par exemple, les pneus de voiture), les lubrifiants, les peintures, les pommades, les adh sifs, les produits d' tanch it , les pigments, les aliments (source de Zn nutritif), les batteries, les ferrites, les retardateurs de flammes, les rubans de premiers secours, etc. Le ZnO est pr sent dans la cro te terrestre sous forme de zincite min rale; cependant, la plupart du ZnO utilis commercialement est produit synth tiquement. En science des mat riaux, le ZnO est souvent appel semi-conducteur II-VI, car le zinc et l'oxyg ne appartiennent respectivement au 2e et au 6e groupe du tableau p riodique. Ce semi-conducteur poss de plusieurs propri t s favorables: une bonne transparence, une grande mobilit des lectrons, une large bande interdite, une forte luminescence temp rature ambiante, etc. Ces propri t s sont d j utilis es dans des applications mergentes pour les lectrodes transparentes dans les crans cristaux liquides et dans les fen tres conomie d' nergie ou protection thermique, ainsi que dans des applications lectroniques du ZnO comme transistors couche mince et diodes lectroluminescentes.

Zinc oxide is an inorganic compound with the formula ZnO. It usually appears as a white powder, nearly insoluble in water. The powder is widely used as an additive into numerous materials and products including plastics, ceramics, glass, cement, rubber (e.g., car tires), lubricants, paints, ointments, adhesives, sealants, pigments, foods (source of Zn nutrient), batteries, ferrites, fire retardants, first aid tapes, etc. ZnO is present in the Earth's crust as the mineral zincite; however, most ZnO used commercially is produced synthetically. In materials science, ZnO is often called a II-VI semiconductor because zinc and oxygen belong to the 2nd and 6th groups of the periodic table, respectively. This semiconductor has several favorable properties: good transparency, high electron mobility, wide band gap, strong room-temperature luminescence, etc. Those properties are already used in emerging applications for transparent electrodes in liquid crystal displays and in energy-saving or heat-protecting windows, and electronic applications of ZnO as thin-film transistors and light-emitting diodes.

Even as US spending on healthcare skyrockets, impoverished Americans continue to fall ill and die of preventable conditions. Although the majority of health outcomes are shaped by non-medical factors, public and private healthcare reform efforts have largely ignored the complex local circumstances that make it difficult for struggling men, women, and children to live healthier lives. In Dying and Living in the Neighborhood, Dr. Prabhjot Singh argues that we must look beyond the walls of the hospital and into the neighborhoods where patients live and die to address the troubling rise in chronic disease. Building on his training as a physician in Harlem, Dr. Singh draws from research in sociology and economics to look at how our healthcare systems are designed and how the development of technologies like the Internet enable us to rethink strategies for assembling healthier neighborhoods. In part I, Singh presents the story of Ray, a patient whose death illuminated how he had lived, his neighborhood context, and the forces that accelerated his decline. In part II, Singh introduces nationally recognized pioneers who are acting on the local level to build critical components of a neighborhood-based health system. In the process, he encounters a movement of people and organizations with similar visions of a porous, neighborhood-embedded healthcare system. Finally, in part III he explores how civic technologies may help forge a new set of relationships among healthcare, public health, and community development. Every rising public health leader, frontline clinician, and policymaker in the country should read this book to better understand how they can contribute to a more integrated and supportive healthcare system.