Nitrogen Defects
Mostrando 1-12 de 76 artigos, teses e dissertações.
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1. De-NOx Performance and Mechanism of Mn-Based Low-Temperature SCR Catalysts Supported on Foamed Metal Nickel
A series of manganese-based catalysts supported on foamed metal nickel (FMN) with various Mn/Ni ratios was prepared for low-temperature selective catalytic reduction (SCR) of NO with NH3 (NH3-SCR). The effects of calcination temperature, amount of added Mn, optimal operating conditions, and H2O on the elimination of nitrogen oxides (de-NOx) performance of ca
J. Braz. Chem. Soc.. Publicado em: 2018-08
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2. Effect of thermal treatment on points defects of Al-N codoped ZnO films
ABSTRACT The effect of annealing temperature on the structural properties of Al-N codoped ZnO films were studied by X-ray diffraction, photoluminescence and Raman spectroscopy. ZnO films were deposited by sputtering technique on silicon substrates at 20 ºC, Al-concentration was kept constant and N-flow was changed to 6, 12 and 15 sccm. A thermal treatment w
Matéria (Rio J.). Publicado em: 19/07/2018
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3. Aloenxerto ósseo cortical desvitalizado com nitrogênio líquido ¿ estudo experimental em ovelhas
Bone grafting is employed in veterinary orthopedics with a variety of purposes as for arthrodesis, spinal fusions, fracture repairs, treatment of delayed or non-unions, filling bone defects, supporting corrective osteotomy, and as replacement in limb sparing techniques for tumor resection. The allograft bone, in contrast to the autologous bone graft, is asso
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2012
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4. Comparative study of BxNyCz nanojunctions fragments
Theoretical analysis of formation energy and geometry was done to compare the relative stabilities of modified carbon nanostructures representative fragments. Structure and energies of formation were calculated at semiempirical level of theory. Depending of B-N pair localization on the molecular structures the formation enthalpy decreases. B-N substitution i
Materials Research. Publicado em: 12/08/2011
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5. Simulações de sensores de gás nanoscópicos baseados em nanotubos de carbono: estrutura eletrônica e transporte de elétrons / Computational simulations of nanoscopic gas sensors based on carbon nanotubes: electronic structure and electronic transport
Since their discovery by S. Iijima in 1991, carbon nanotubes have been considered as one of the most promising nanostructured materials for the development of new nanoscopic electronic devices. Due to its high surface area to volume ratio, this material stands out as a candidate for possible gas sensoring applications. In this thesis, we have studied, by mea
Publicado em: 2011
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6. Estudo da dopagem em nanotubos de carbono por espectroscopia Raman ressonante.
Doping of single wall carbon nanotubes with boron, nitrogen, phosphorous and sulfur was studied by resonance Raman spectroscopy. The doping atoms were inserted in the tube walls during synthesis, by using chemical vapor deposition, laser ablation and arc discharge methods. The analysis of the Raman spectra shows that the insertion of dopants generates tubes
Publicado em: 2009
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7. Influência dos elementos de liga no intervalo de solidificação do aço inoxidável martensítico CA6NM. / Alloying elements influence on the CA6NM martensitic stainless steel solidification interval.
The influence of alloying elements like Chromium, Nickel, Carbon and Nitrogen on the solidification interval on a CA6NM martensitic stainless steel casting was investigated. This steel class, mainly used on large castings, applies due to the fact that it has very good impact resistance, and satisfactory corrosion properties. Besides that, this stainless stee
Publicado em: 2009
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8. Nitriding using cathodic cage technique of martensitic stainless steel AISI 420 with addition of CH4
AISI 420 martensitic stainless steel samples were nitrided by cathodic cage technique with addition of methane in the atmosphere aiming to reduce chromium nitride precipitation, to increase hardness and wear resistance without the presence of characteristic defects inherent to the ionic nitriding process. Microhardness measurements and X-ray analysis confirm
Matéria (Rio de Janeiro). Publicado em: 2008-06
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9. THEORETICAL STUDY OF THE STABILITY AND ELECTRONIC PROPERTIES IN THE DEFECTS IN GaN NANOTUBES / ESTUDO TEÓRICO DA ESTABILIDADE E PROPRIEDADES ELETRÔNICAS DE DEFEITOS EM NANOTUBOS DE GaN
The stability and electronic properties of antisities, vacancies and substitutional Si and C impurities in GaN nanotubes are studied using spin-polarized density functional theory within the local density approximation (LDA) to the exchange-correlation functional. We investigated these defects in both nanotubes the zigzag (10,0)and the armchair (6,6), which
Publicado em: 2008
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10. Propriedades vibracionais de defeitos de nitrogênio em nanotubos de carbono / Vibrational Properties of Nitrogen Defects on Carbon Nanotubes
O trabalho anteriormente realizado pelo nosso grupo, onde foram simulados defeitos de nitrogênio em nanotubos de carbono, apresentou resultados interessantes relativos às energias e propriedades eletrônicas. A interpretacão dos resultados teóricos obtidos levou à proposta da Divacância rodeada por 4 Nitrogênios como estrutura mais estável para o nit
Publicado em: 2008
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11. Use of propolis and ascorbic acid on goat semen cryopreservation / Uso da própolis e do ácido ascórbico na criopreservação do sêmen caprino
The objectives of this study were to verify if the propolis and ascorbic acid contain effect on plasmatic membrane integrity of goats spermatozoa as well as investigate the potential of these antioxidants on the use of goats spermatozoa cryopreservation extenders. Semen from five adults goats were used, totalizing 5 semen samples for each one. After semen co
Publicado em: 2008
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12. Estudo da regeneração de aditivos para catalisadores de craqueamento aluminofosfatos (ALPOs)e silicoaluminofosfatos (SAPOs)
Heterogeneous catalysts such as aluminophosphate and silicoaluminophosphate, molecular sieves with AEL of ALPO-11 and SAPO-11, were synthesized by the hydrothermal method with the following molar composition: 2.9 Al +3.2 P + 3.5 DIPA +32.5 H20 (ALPO-11); 2.9 Al +3.2 P + 0.5 Si + 3.5 DIPA +32.5 H20 (SAPO-11) starting from silica (only in the SAPO-11), pseudob
Publicado em: 2007