Navegação Ciências Exatas e da Terra por Autor "Morais, Jonder"
Resultados 1-20 de 28
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Angular and temperature dependence of the magnetic circular dichroism in 4d core-level photoemission from Gd(0001)
Denecke, Reinhard; Morais, Jonder; Ynzunza, Ramon X.; Fecher, Gerhard H.; Menchero, Jose G.; Liesegang, John; Kortright, Jeff B.; Hussain, Zahid; Fadley, Charles S. (2002) [Artigo de periódico]We present experimental and theoretical results for the angular and temperature dependence of magnetic circular dichroism in Gd 4d core-level photoelectron emission from a Gd(0001) surface in both normal and off-normal ... -
Atomic transport and chemical stability during annealing of ultrathin Al/sub 2/O/sub 3/ films on Si
Krug, Cristiano; Rosa, Elisa Brod Oliveira da; Almeida, Rita Maria Cunha de; Morais, Jonder; Baumvol, Israel Jacob Rabin; Salgado, Tania Denise Miskinis; Stedile, Fernanda Chiarello (2000) [Artigo de periódico]Ultrathin films of Al₂O₃ deposited on Si were submitted to rapid thermal annealing in vacuum or in oxygen atmosphere, in the temperature range from 600 to 800 °C. Nuclear reaction profiling with subnanometric depth resolution ... -
Carbon supported Pd–Cu nanoalloys : support and valence band structure influence on reduction and oxidation reactions
Castegnaro, Marcus Vinicíus; Gorgeski, Andreia; Alves, Maria do Carmo Martins; Morais, Jonder (2021) [Artigo de periódico]The present study has tracked the changes in the electronic and structural properties of Pd–Cu nanoalloys that were influenced by the composition and chosen support. Carbon supported Pd–Cu nanoalloys (PdxCu1−x/C for x = ... -
Charge transfer effects on the chemical reactivity of PdxCu1−x nanoalloys
Castegnaro, Marcus Vinicíus; Gorgeski, Andreia; Balke, Benjamin; Alves, Maria do Carmo Martins; Morais, Jonder (2016) [Artigo de periódico]This work reports on the synthesis and characterization of PdxCu1−x (x = 0.7, 0.5 and 0.3) nanoalloys obtained via an eco-friendly chemical reduction method based on ascorbic acid and trisodium citrate. The average size ... -
Comment on "Atomic transport and chemical stability during annealing of ultrathin Al/sub 2/O/sub 3/ films on Si" : reply
Krug, Cristiano; Rosa, Elisa Brod Oliveira da; Almeida, Rita Maria Cunha de; Morais, Jonder; Baumvol, Israel Jacob Rabin; Salgado, Tania Denise Miskinis; Stedile, Fernanda Chiarello (2001) [Artigo de periódico] -
Composition, atomic transport, and chemical stability of ZrAl/sub x/O/sub y/ ultrathin films deposited on Si(001)
Morais, Jonder; Rosa, Elisa Brod Oliveira da; Pezzi, Rafael Peretti; Miotti, Leonardo; Baumvol, Israel Jacob Rabin (2001) [Artigo de periódico]The stability of a ZrAlxOy film sputtered on Si upon thermal annealing in vacuum or in O2 was investigated. X-ray diffraction indicated that the as-deposited film was amorphous and remained so after annealing. Rutherford ... -
Diffusion reaction of oxigen in aluminum oxide films on silicon
Rosa, Elisa Brod Oliveira da; Baumvol, Israel Jacob Rabin; Morais, Jonder; Almeida, Rita Maria Cunha de; Papaleo, Ricardo Meurer; Stedile, Fernanda Chiarello (2002) [Artigo de periódico]Aluminum oxide films deposited on silicon by atomic layer chemical vapor deposition were annealed in an ¹⁸O-enriched oxygen atmosphere under various conditions of temperature, time, and pressure. Cavity formation at the ... -
A dispenser–reactor apparatus applied for in situ XAS monitoring of Pt nanoparticle formation
Boita, Jocenir; Castegnaro, Marcus Vinicíus; Alves, Maria do Carmo Martins; Morais, Jonder (2015) [Artigo de periódico]In situ time-resolved X-ray absorption spectroscopy (XAS) measurements collected at the Pt L3-edge during the synthesis of Pt nanoparticles (NPs) in aqueous solution are reported. A specially designed dispenser–reactor ... -
Electronic and crystallographic structure, hard x-ray photoemission, and mechanical and transport properties of the half-metallic Heusler compound Co2MnGe
Ouardi, Siham; Fecher, Gerhard H.; Balke, Benjamin; Beleanu, Andreea; Kozina, Xeniya; Stryganyuk, Gregory; Felser, Claudia; Klöß, Werner; Schrader, Hartmut; Bernardi, Fabiano; Morais, Jonder; Ikenaga, Eiji; Yamashita, Yoshiyuki; Ueda, Shigenori; Kobayashi, Keisuke (2011) [Artigo de periódico]This work reports on the electronic and crystalline structure and the mechanical, magnetic, and transport properties of the polycrystalline Heusler compound Co2MnGe. The crystalline structure was examined in detail by ... -
Environment of hafnium and silicon in Hf-based dielectric films : an atomistic study by x-ray absorption spectroscopy and x-ray diffraction
Morais, Jonder; Miotti, Leonardo; Bastos, Karen Paz; Teixeira, Sergio Ribeiro; Baumvol, Israel Jacob Rabin; Rotondaro, Antonio L.P.; Chambers, James Joseph; Visokay, Mark R.; Colombo, Luigi; Alves, Maria do Carmo Martins (2005) [Artigo de periódico]The atomic structure of HfSiO and HfSiON was investigated before and after thermal annealing using x-ray diffraction and x-ray absorption spectroscopy. In HfSiO, the Hf atoms are arranged in a monoclinic HfO2 structure ... -
Exchange-diffusion reactions in HfSiON during annealing studied by Rutherford backscattering spectrometry, nuclear reaction analysis and narrow resonant nuclear reaction profiling
Miotti, Leonardo; Bastos, Karen Paz; Soares, Gabriel Vieira; Driemeier, Carlos Eduardo; Pezzi, Rafael Peretti; Morais, Jonder; Baumvol, Israel Jacob Rabin; Rotondaro, Antonio L.P.; Visokay, Mark R.; Chambers, James Joseph; Quevedo-Lopez, M.; Colombo, Luigi (2004) [Artigo de periódico]HfSiON films deposited on Si (001) by reactive sputtering were submitted to rapid thermal annealing at 1000 °C in vacuum, N2 and O2 atmospheres. The stability of the dielectric was evaluated by measuring the atomic transport ... -
Geometric, electronic, and magnetic structure of Co/sub 2/FeSi: Curie temperature and magnetic moment measurements and calculations
Wurmehl, Sabine; Fecher, Gerhard H.; Kandpal, Hem Chandra; Ksenofontov, Vadim; Felser, Claudia; Lin, Hong-Ji; Morais, Jonder (2005) [Artigo de periódico]In this work a simple concept was used for a systematic search for materials with high spin polarization. It is based on two semiempirical models. First, the Slater-Pauling rule was used for estimation of the magnetic ... -
Incoherent magnetization rotation observed in subnanosecond time-resolving x-ray photoemission electron microscopy
Schneider, Claus M.; Kuksov, Andrej; Krasyuk, Alexander; Oelsner, Andreas; Neeb, Daniel; Nepijko, Sergej A.; Schönhense, Gerd; Mönch, Ingolf; Kaltofen, Rainer; Morais, Jonder; Nadaï, Celine de; Brookes, N.B. (2004) [Artigo de periódico]We present recent results of time-resolved x-ray photoemission electron microscopy on permalloy microstructures. The stroboscopic experiments feature a time-resolution of Dtø130 ps.We observe a strong influence of incoherent ... -
Influence of the thermal processing and doping on LaMnO3 and La0.8A0.2MnO3 (A = Ca, Sr, Ba) perovskites prepared by auto-combustion for removal of VOCs
Di Benedetto, Natasha; De Los Santos, Carolina; Yeste Sigüenza, María Del Pilar; Morais, Jonder; Alves, Maria do Carmo Martins; Amaya, Alejandro; Suescun, Leopoldo; Gatica Casas, José Manuel; Vidal Muñoz, Hilario; Castiglioni, Jorge (2022) [Artigo de periódico]Single-phase oxygen stoichiometric LaMnO3 and doped La0.8A0.2MnO3 (A = Ca, Sr, Ba) perovskites have been prepared by a simple one-step auto-combustion method. Cation-deficient LaMnO3+δ and La0.8A0.2MnO3+δ were obtained by ... -
Initial stages of SiC oxidation investigated by ion scattering and angle-resolved x-ray photoelectron spectroscopies
Radtke, Claudio; Baumvol, Israel Jacob Rabin; Morais, Jonder; Stedile, Fernanda Chiarello (2001) [Artigo de periódico]Initial stages of oxidation of single-crystal, Si-faced silicon carbide were investigated using ion scattering and angle-resolved x-ray photoelectron spectroscopies. The very first oxidation products are shown to be silicon ... -
Integrity of hafnium silicate/silicon dioxide ultrathin films on Si
Morais, Jonder; Miotti, Leonardo; Soares, Gabriel Vieira; Teixeira, Sergio Ribeiro; Pezzi, Rafael Peretti; Bastos, Karen Paz; Baumvol, Israel Jacob Rabin; Rotondaro, Antonio L.P.; Chambers, Jim J.; Visokay, Mark R.; Colombo, Luigi (2002) [Artigo de periódico]Rapid thermal annealing at 1000 °C of (HfO2)12x(SiO2)x pseudobinary alloy films deposited on Si were performed in N2 or O2 atmospheres. The effects on the atomic transport, structure, and composition were investigated using ... -
Magnetic dichroism in core-level photoemission from Gd(0001)
Morais, Jonder; Fecher, Gerhard H.; Denecke, Reinhard; Hussain, Zahid; Fadley, Charles S. (2000) [Artigo de periódico]This work reports on magnetic dichroism in photoemission from the Gd 4l(l=s,p,d, f) core level of in-plane magnetized Gd films excited with linearly, circularly, and unpolarized light. Thin Gd films of about 100 ML thickness ... -
Oxygen reaction-diffusion in metalorganic chemical vapor deposition HfO/sub 2/ films annealed in O/sub 2/
Bastos, Karen Paz; Morais, Jonder; Miotti, Leonardo; Pezzi, Rafael Peretti; Soares, Gabriel Vieira; Baumvol, Israel Jacob Rabin; Hegde, R.I.; Tseng, Hsing-Huang; Tobin, Phil J. (2002) [Artigo de periódico]Composition, atomic transport, and chemical reaction were investigated following annealing in O2 of ultrathin HfO2 films deposited on Si substrates thermally nitrided in NO. The as-prepared thin film composition was ... -
Photocatalytic water splitting with noble-metal free cocatalysts for a comprehensive study of two nonidentical photoreactors designs
Vicentini, Jean César Marinozi; Cardoso, Rafael Manieri Pires; Subtil, Gimerson Weigert; Tavares, Fernanda de Oliveira; Oliveira, Daiane Marques de; Yassue-Cordeiro, Patricia Hissae; Enzweiler, Heveline; Gimenes, Marcelino Luiz; Alves, Maria do Carmo Martins; Morais, Jonder; Scaliante, Mara Heloisa Neves Olsen; Souza, Marcos de (2020) [Artigo de periódico]Here, the authors (i) discuss the most prominent co-catalyst for H2 generation struc tured in the form of Me-TiO2/MCM-41 (Me: Ag, Co, Cu, Ni) based on structural, electronic, textural, morphological and optical characterization ... -
A reaction cell for time-resolved in situ XAS studies during wet chemical synthesis : the Cu2(OH)3Cl case
Boita, Jocenir; Alves, Maria do Carmo Martins; Morais, Jonder (2014) [Artigo de periódico]The use of in situ time-resolved dispersive X-ray absorption spectroscopy (DXAS) to monitor the formation of Cu2(OH)3Cl particles in an aqueous solution is reported. The measurements were performed using a dedicated reaction ...