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Fabricação e caracterização de filmes finos de brometo de tálio (TIBr); Fabrication and characterization of thallium bromide (TlBr) thin films

Destefano, Natália
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/07/2009 PT
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Por ser um semicondutor de elevado número atômico, elevada densidade de massa e largo gap de energia, o brometo de tálio (TlBr) é um material promissor para a detecção da radiação à temperatura ambiente. Entretanto, existem poucos trabalhos relacionados ao estudo deste material sob forma de filme fino policristalino para produção em grandes áreas como desejado para aplicações médicas. Neste trabalho, as técnicas de spray pyrolysis e evaporação térmica foram avaliadas como métodos alternativos para a deposição de filmes de TlBr policristalinos. Ambas as técnicas apresentam relativo baixo custo e podem facilmente ser expandidas para grandes áreas. O objetivos deste trabalho é o estudo da influência das principais condições de crescimento nas propriedades (estruturais, ópticas e elétricas) finais dos filmes de TlBr. Para os filmes produzidos por spray pyrolysis água mili-Q foi utilizada como solvente. A solução (0,10 g de TlBr dissolvidos em 100 g de água) foi agitada à temperatura de 70ºC. Cada deposição foi realizado mantendo os substratos (1cm x 1cm) à temperatura de 100ºC, com um fluxo de nitrogênio (N2) de 8 1/min e um fluxo de solução de aproximadamente 1/90 (ml/s). A distância bico de spray-substrato utilizada foi de 19 cm. Os filmes de TlBr evaporados foram crescidos pela evaporação térmica do material a partir de um cadinho de tungstênio. Um sistema de aquecimento dos substratos foi implantado e permitiu a variação da temperatura destes durante a deposição desde a temperatura ambiente até 200ºC. A separação substrato-superfície de evaporação...

Obtenção de ZnO nanoestruturado e caracterização de propriedades e atividade fotocatalítica

Nunes, Marilia dos Santos
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
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Este trabalho versou sobre a obtenção de partículas nanoestruturadas de ZnO pela técnica de evaporação térmica a partir de zinco metálico. Basicamente, a síntese ocorria em um reator de quatzo colocado em um forno tipo mufla, onde o zinco metálico reagia com uma atmosfera oxidante, proporcionada pela injeção de ar comprimido. Inicialmente, o forno era aquecido a temperaturas que variaram de 850 a 1050°C. Posteriormente, a amostra de zinco metálico era inserida na zona de aquecimento no interior do tubo, em quantidade de 2,5g, 5g, 10g, 20g e 30g. A injeção de argônio (99,99% de pureza), para o transporte das partículas de ZnO para fora da zona de reação, ocorria com um fluxo de 1 a 5L/min. O tempo de reação foi controlado e as regiões de ocorrência das reações variadas. Após o término das reações, o forno era resfriado à temperatura ambiente para a realização da coleta das amostras. A pressão utilizada durante as reação foi a pressão atmosférica. O material produzido foi analisado para a caracterização da estrutura cristalina (por difração de raios-x), morfologia (por microscopia eletrônica de varredura e transmissão, com auxílio do software Image Tool para a estimativa de tamanho de partícula) e área superficial (método BET). O band gap do ZnO foi determinado por análise de transmitância...

Síntese de nanofios de óxidos semicondutores para aplicações em dispositivos ópticos e eletrônicos

Savu, Raluca
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Tese de Doutorado Formato: 228 f. : il.
POR
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Pós-graduação em Ciência e Tecnologia de Materiais - FC; A presente pesquisa teve como principal objetivo a obtenção de estruturas nanométricas de óxido de índio, óxido de estanho e óxido de zinco por evaporação térmica e síntese hidrotérmica e a construção e teste de sensores de gases e de fotodetectores de ultravioleta baseados nessas nanoestruturas. Foram realizados estudos da influência dos parâmetros experimentais das duas rotas de síntese usadas sobre as morfologias e as propriedades das estruturas. Para a obtenção das camadas nanoestruturadas por evaporação térmica foi especialmente construído um forno tubular que permitiu o controle da temperatura de deposição independente da temperatura de evaporação e da distância entre a fonte de evaporação e o substrato. Esses parâmetros, pouco explorados nas pesquisas reportadas na literatura, exerceram uma grande influência sobre a morfologia e as propriedades dos nanofios obtidos. O equipamento permitiu ainda um controle preciso da composição da atmosfera e da pressão de síntese. Na síntese química em solução, a construção de um reator hidrotérmico permitiu o estudo da influência da taxa de resfriamento sobre as dimensões...

Structural and optical characterization of ZnO nanowires grown on alumina by thermal evaporation method

Mute, A.; Peres, M.; Peiris, T.C.; Lourenço, A.C.; Jensen, L.R.; Monteiro, T.
Fonte: ASP Publicador: ASP
Tipo: Artigo de Revista Científica
ENG
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Zinc oxide nanowires have been grown on alumina substrate by thermal evaporation of zinc nanopowder in the presence of oxygen flow. The growth was performed under ambient pressure and without the use of foreign catalyst. Scanning electron microscopy (SEM) observation showed that the as-grown sample consists of bulk ZnO crystal on the substrate surface with nanowires growing from this base. Growth mechanism of the observed morphology is suggested to be governed by the change of zinc vapour supersaturation during the growth process. X-ray diffraction (XRD) measurement was used to identify the crystalline phase of the nanowires. Optical properties of the nanowires were investigated using Raman scattering and photoluminescence (PL). The appearance of dominant, Raman active E2 (high) phonon mode in the Raman spectrum has confirmed the wurtzite hexagonal phase of the nanowires. With above bandgap excitation the low temperature PL recombination is dominated by donor bound exciton luminescence at ~3.37 eV with a narrow full width at half maximum. Free exciton emission is also seen at low temperature and can be observed up to room temperature. The optical data indicates that the grown nanowires have high optical quality.; FCT - POCI/FIS/72843/2006; FCT - PTDC/FIS/66262/2006

Thermal Evaporation Synthesis and Properties of ZnO Nano/Microstructures Using Carbon Group Elements as the Reducing Agents

Lv, H; Sang, DD; Li, HD; Du, XB; Li, DM; Zou, GT
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 21/01/2010 EN
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ZnO nano/microstructures have been formed by thermal evaporation method using ZnO powders mixed with carbon group elements (C, Si, Ge, Sn, or Pb) as the reducing agent. For cases of mixed precursors of ZnO/C, ZnO/Si, and ZnO/Ge, the pure ZnO nano/microstructures are realized, while for ZnO/Sn (ZnO/Pb) systems, the phase of Pb2O3(Zn2SnO4) generally are represented in the ZnO products. The appearance of Pb2O3(Zn2SnO4) is attributed to the lower melting point and higher vapor pressure of Sn (Pb) in the heating and evaporation processes. The morphologies and sizes of the products are controlled by adjusting the growth regions and/or introducing gaseous argon. Room temperature (RT) photoluminescence spectra indicate that the intensity (peak position) of the ultraviolet emission is increased (redshift) due to the existence of Zn2SnO4 phase in the ZnO products. The Pb2O3(Zn2SnO4) phase in ZnO nano/microstructures plays a important role in enhancing the saturation magnetizations of RT ferromagnetism with respect to the case of pure ZnO products fabricated by the precursor of mixed ZnO and graphite.

Synthesis of Tapered CdS Nanobelts and CdSe Nanowires with Good Optical Property by Hydrogen-Assisted Thermal Evaporation

Wang, Min; Fei, GuangTao
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 10/07/2009 EN
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The tapered CdS nanobelts and CdSe nanowires were prepared by hydrogen-assisted thermal evaporation method. Different supersaturation leads to two different kinds of 1D nanostructures. The PL measurements recorded from the as-prepared tapered CdS nanobelts and CdSe nanowires show only a bandgap emission with relatively narrow full-width half maximum, which means that they possess good optical property. The as-synthesized high-quality tapered CdS nanobelts and CdSe nanowires may be excellent building blocks for photonic devices.

Synthesis of Novel Double-Layer Nanostructures of SiC–WOxby a Two Step Thermal Evaporation Process

Kim, Hyeyoung; Senthil, Karuppanan; Yong, Kijung
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 19/04/2009 EN
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A novel double-layer nanostructure of silicon carbide and tungsten oxide is synthesized by a two-step thermal evaporation process using NiO as the catalyst. First, SiC nanowires are grown on Si substrate and then high density W18O49nanorods are grown on these SiC nanowires to form a double-layer nanostructure. XRD and TEM analysis revealed that the synthesized nanostructures are well crystalline. The growth of W18O49nanorods on SiC nanowires is explained on the basis of vapor–solid (VS) mechanism. The reasonably better turn-on field (5.4 V/μm) measured from the field emission measurements suggest that the synthesized nanostructures could be used as potential field emitters.

Intense ultraviolet emission from needle-like WO3 nanostructures synthesized by noncatalytic thermal evaporation

Park, Sunghoon; Kim, Hyunsu; Jin, Changhyun; Lee, Chongmu
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 13/07/2011 EN
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Photoluminescence measurements showed that needle-like tungsten oxide nanostructures synthesized at 590°C to 750°C by the thermal evaporation of WO3 nanopowders without the use of a catalyst had an intense near-ultraviolet (NUV) emission band that was different from that of the tungsten oxide nanostructures obtained in other temperature ranges. The intense NUV emission might be due to the localized states associated with oxygen vacancies and surface states.

Selective Growth of Vertical-aligned ZnO Nanorod Arrays on Si Substrate by Catalyst-free Thermal Evaporation

Wang, H; Zhang, ZP; Wang, XN; Mo, Q; Wang, Y; Zhu, JH; Wang, HB; Yang, FJ; Jiang, Y
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 21/08/2008 EN
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By thermal evaporation of pure ZnO powders, high-density vertical-aligned ZnO nanorod arrays with diameter ranged in 80–250 nm were successfully synthesized on Si substrates covered with ZnO seed layers. It was revealed that the morphology, orientation, crystal, and optical quality of the ZnO nanorod arrays highly depend on the crystal quality of ZnO seed layers, which was confirmed by the characterizations of field-emission scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and photoluminescence measurements. For ZnO seed layer with wurtzite structure, the ZnO nanorods grew exactly normal to the substrate with perfect wurtzite structure, strong near-band-edge emission, and neglectable deep-level emission. The nanorods synthesized on the polycrystalline ZnO seed layer presented random orientation, wide diameter, and weak deep-level emission. This article provides a C-free and Au-free method for large-scale synthesis of vertical-aligned ZnO nanorod arrays by controlling the crystal quality of the seed layer.

Growth of catalyst-free high-quality ZnO nanowires by thermal evaporation under air ambient

Liu, Ping; Li, Yanbin; Guo, Yanqing; Zhang, Zhenhua
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 13/04/2012 EN
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ZnO nanowires have been successfully fabricated on Si substrate by simple thermal evaporation of Zn powder under air ambient without any catalyst. Morphology and structure analyses indicated that ZnO nanowires had high purity and perfect crystallinity. The diameter of ZnO nanowires was 40 to 100 nm, and the length was about several tens of micrometers. The prepared ZnO nanowires exhibited a hexagonal wurtzite crystal structure. The growth of the ZnO nanostructure was explained by the vapor-solid mechanism. The simplicity, low cost and fewer necessary apparatuses of the process would suit the high-throughput fabrication of ZnO nanowires. The ZnO nanowires fabricated on Si substrate are compatible with state-of-the-art semiconductor industry. They are expected to have potential applications in functional nanodevices.

Solvent Free Fabrication of Micro and Nanostructured Drug Coatings by Thermal Evaporation for Controlled Release and Increased Effects

Zarie, Eman S.; Kaidas, Viktor; Gedamu, Dawit; Mishra, Yogendra K.; Adelung, Rainer; Furkert, Franz H.; Scherließ, Regina; Steckel, Hartwig; Groessner-Schreiber, Birte
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 01/08/2012 EN
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Nanostructuring of drug delivery systems offers many promising applications like precise control of dissolution and release kinetics, enhanced activities, flexibility in terms of surface coatings, integration into implants, designing the appropriate scaffolds or even integrating into microelectronic chips etc. for different desired applications. In general such kind of structuring is difficult due to unintentional mixing of chemical solvents used during drug formulations. We demonstrate here the successful solvent-free fabrication of micro-nanostructured pharmaceutical molecules by simple thermal evaporation (TE). The evaporation of drug molecules and their emission to a specific surface under vacuum led to controlled assembling of the molecules from vapour phase to solid phase. The most important aspects of thermal evaporation technique are: solvent-free, precise control of size, possibility of fabricating multilayer/hybrid, and free choice of substrates. This could be shown for twenty eight pharmaceutical substances of different chemical structures which were evaporated on surfaces of titanium and glass discs. Structural investigations of different TE fabricated drugs were performed by atomic force microscopy, scanning electron microscopy and Raman spectroscopy which revealed that these drug substances preserve their structurality after evaporation. Titanium discs coated with antimicrobial substances by thermal evaporation were subjected to tests for antibacterial or antifungal activities...

Influence of the layer thickness in plasmonic gold nanoparticles produced by thermal evaporation

Gaspar, D.; Pimentel, A. C.; Mateus, T.; Leitão, J. P.; Soares, J.; Falcão, B. P.; Araújo, A.; Vicente, A.; Filonovich, S. A.; Águas, H.; Martins, R.; Ferreira, I.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 03/04/2013 EN
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Metallic nanoparticles (NPs) have received recently considerable interest of photonic and photovoltaic communities. In this work, we report the optoelectronic properties of gold NPs (Au-NPs) obtained by depositing very thin gold layers on glass substrates through thermal evaporation electron-beam assisted process. The effect of mass thickness of the layer was evaluated. The polycrystalline Au-NPs, with grain sizes of 14 and 19 nm tend to be elongated in one direction as the mass thickness increase. A 2 nm layer deposited at 250°C led to the formation of Au-NPs with 10-20 nm average size, obtained by SEM images, while for a 5 nm layer the wide size elongates from 25 to 150 nm with a mean at 75 nm. In the near infrared region was observed an absorption enhancement of amorphous silicon films deposited onto the Au-NPs layers with a corresponding increase in the PL peak for the same wavelength region.

Seed/catalyst-free growth of zinc oxide nanostructures on multilayer graphene by thermal evaporation

Ahmad, Nurul Fariha; Rusli, Nurul Izni; Mahmood, Mohamad Rusop; Yasui, Kanji; Hashim, Abdul Manaf
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 18/02/2014 EN
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We report the seed/catalyst-free growth of ZnO on multilayer graphene by thermal evaporation of Zn in the presence of O2 gas. The effects of substrate temperatures were studied. The changes of morphologies were very significant where the grown ZnO structures show three different structures, i.e., nanoclusters, nanorods, and thin films at 600°C, 800°C, and 1,000°C, respectively. High-density vertically aligned ZnO nanorods comparable to other methods were obtained. A growth mechanism was proposed based on the obtained results. The ZnO/graphene hybrid structure provides several potential applications in electronics and optoelectronics.

Surface Morphology and Sensing Property of NiO-WO3 Thin Films Prepared by Thermal Evaporation

Na, Dong-myong; Satyanarayana, L.; Choi, Gwang-Pyo; Shin, Yong-Jin; Park, Jin Seong
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 01/12/2005 EN
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WO3 and NiO-WO3 thin films of various thicknesses were deposited on an Al2O3-Si (alumina-silicon) substrate using high vacuum thermal evaporation. After annealing at 500°C for 30 minutes in air, the crystallanity and surface morphology of WO3 and NiO-WO3 thin films were investigated using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). It is observed that the WO3 thin films were resulted in cracks between the polycrystalline grains and the grain growth was increased with increasing thickness causing deteriorated sensing characteristics of the films. On the other hand, an optimum deposition of NiO on WO3 thin film has inhibited the grain growth and improved the sensitivity of the films. The inhibition is limited to a certain thickness of WO3 and NiO content (mol %) of inclusion and below or above this limitation the grain growth could not be suppressed. Moreover, the deposition sequence of NiO and WO3 is also playing a significant role in controlling the grain growth. A probable mechanism for the control of grain growth and improving the sensing property has been discussed.

Seed/catalyst-free growth of zinc oxide on graphene by thermal evaporation: effects of substrate inclination angles and graphene thicknesses

Ahmad, Nurul Fariha; Yasui, Kanji; Hashim, Abdul Manaf
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
Publicado em 22/01/2015 EN
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A seed/catalyst-free growth of ZnO on graphene by thermal evaporation of Zn in the presence of O2 gas was further studied. The effects of substrate positions and graphene thicknesses on the morphological, structural, and optical properties were found to be very pronounced. By setting the substrate to be inclined at 90°, the growth of ZnO nanostructures, namely, nanoclusters and nanorods, on single-layer (SL) graphene was successfully realized at temperatures of 600°C and 800°C, respectively. For the growth on multilayer (ML) graphene at 600°C with an inclination angle of 90°, the grown structures show extremely thick and continuous cluster structures as compared to the growth with substrate’s inclination angle of 45°. Moreover, the base of nanorod structures grown at 800°C with an inclination angle of 90° also become thicker as compared to 45°, even though their densities and aspect ratios were almost unchanged. Photoluminescence (PL) spectra of the grown ZnO structures were composed of the UV emission (378–386 nm) and the visible emission (517–550 nm), and the intensity ratio of the former emission (IUV) to the latter emission (IVIS) changed, depending on the temperature. The structures grown at a low temperature of 600°C show the highest value of IUV/IVIS of 16.2...

Tungsten oxide thin films grown by thermal evaporation with high resistance to leaching

Corrêa,Diogo S.; Pazinato,Julia C. O.; Freitas,Maurício A. de; Dorneles,Lucio S.; Radtke,Claudio; Garcia,Irene T. S.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2014 EN
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67.88201%
Tungsten oxides show different stoichiometries, crystal lattices and morphologies. These characteristics are important mainly when they are used as photocatalysts. In this work tungsten oxide thin films were obtained by thermal evaporation on (100) silicon substrates covered with gold and heated at 350 and 600 ºC, with different deposition times. The stoichiometry of the films, morphology, crystal structure and resistance to leaching were characterized through X-ray photoelectron spectroscopy, micro-Raman spectroscopy, scanning and transmission electron microscopy, X-ray diffractometry, Rutherford backscattering spectrometry and O16(α,α')O16 resonant nuclear reaction. Films obtained at higher temperatures show well-defined spherical nanometric structure; they are composed of WO3.1 and the presence of hydrated tungsten oxide was also observed. The major crystal structure observed is the hexagonal. Thin films obtained through thermal evaporation present resistance to leaching in aqueous media and excellent performance as photocatalysts, evaluated through the degradation of the methyl orange dye.

Thin film deposition of Ge33As12 Se55 by pulsed laser deposition and thermal evaporation: comparison of properties

Jarvis, Ruth; Wang, Rongping; Rode, Andrei V; Zha, Congji; Luther-Davies, Barry
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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67.88201%
Thin films of Ge33As12Se55 were produced using two deposition techniques, ultra-fast pulsed laser deposition (UFPLD) and thermal evaporation (TE), and their properties have been investigated. The chemical composition of the UFPLD films was virtually ident

Thermal Evaporation of Gas from X-ray Clusters

Loeb, Abraham
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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A fraction of the thermal protons in the outer envelope of an X-ray cluster have velocities that exceed the local escape speed from the cluster gravitational potential. The Coulomb mean-free-path of these protons is larger than the virial radius of the cluster at temperatures >2.5 keV. The resulting leakage of suprathermal particles generates a collisionless shock in neighboring voids and fills them with heat and magnetic fields. The momentum flux of suprathermal particles cannot be confined by magnetic tension at the typical field strength in the periphery of cluster halos (<<1 micro-gauss). Over a Hubble time, thermal evaporation could drain up to a tenth of the cluster gas at its virial temperature. The evaporated fraction could increase dramatically if additional heat is deposited into the gas by cluster mergers, active galactic nuclei or supernovae. Thermal evaporation is not included in existing cosmological simulations since they are based on the fluid approximation. Measurements of the baryon mass fraction in the outer envelopes of hot clusters (through their Sunyaev-Zel'dovich effect or X-ray emission) can be used to empirically constrain their evaporation rate.; Comment: 5 pages, 1 figure

The role of thermal evaporation in galaxy formation

Nipoti, Carlo; Binney, James
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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In colour-magnitude diagrams most galaxies fall in either the ``blue cloud'' or the ``red sequence'', with the red sequence extending to significantly brighter magnitudes than the blue cloud. The bright-end of the red sequence comprises elliptical galaxies (Es) with boxy isophotes and luminosity profiles with shallow central cores, while fainter Es have disky isophotes and power-law inner surface-brightness (SB) profiles. An analysis of published data reveals that the centres of galaxies with power-law central SB profiles have younger stellar populations than the centres of cored galaxies. We argue that thermal evaporation of cold gas by virial-temperature gas plays an important role in determining these phenomena. In less massive galaxies, thermal evaporation is not very efficient, so significant amounts of cold gas can reach the galaxy centre and fill a central core with newly formed stars, consistent with the young stellar ages of the cusps of Es with power-law SB profiles. In more massive galaxies, cold gas is evaporated within a dynamical time, so star formation is inhibited, and a core in the stellar density profile produced by dissipationless dynamics cannot be refilled. The different observed properties of AGN in higher-mass and lower-mass ellipticals are also explained because in the former the central black holes invariably accrete hot gas...

Growth of polyhedral stacked micro columns and micro particles of zinc by thermal evaporation and condensation technique

Rivera-Flores,B. L.; Diaz-Becerril,T.; Bueno-Avendaño,C.; Galeazzi-Isasmendi,R.; Rosendo-Andrés,E.; García-Salgado,G.; Juárez-Santiesteban,H.; Pacio-Castillo,M.; Morales-Ruiz,C.; Silva-González,R.
Fonte: Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. Publicador: Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C.
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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Metallic zinc nano structures have been grown by the thermal evaporation and condensation technique using a mixture of zinc and manganese oxide powders and nitrogen as carrier gas. 650 °C and 1 atm were used as processing temperature and pressure, respectively. It was found that the shape of zinc structures is dependent on the source materials. When a mixture of Zn/MnO2 powders is used as raw material micro-particles with oblate spherical shape and micro-columns are obtained. On the other hand, when only zinc powder is used as source material, spherical stones without facets are deposited. It is assumed that evaporation from the source is inhibited when a mixture of Zn and MnO2 is used. Therefore, supersaturation downstream from the source changes and as a consequence the morphology of the structures is modified. Synthesized material is make-up of zinc atoms and no other impurities or catalytic particles were detected according to elemental analysis. Vapor-solid is though as mechanism for growing those zinc structures.