Nitrogen Oxides
Mostrando 13-24 de 108 artigos, teses e dissertações.
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13. Structural and Mechanical Properties of Radiofrequency Ar-N2 Plasma Nitrided Aluminium
Aluminium (Al) samples were nitrided in 13.56 MHz radiofrequency (RF) discharge of 70:30 vol.% Ar:N2 mixture at substrate temperature of 400 °C and RF power of 300 W for different fill pressures and treatment times. The nitrided samples were then characterized for their structural and mechanical properties using x-ray diffraction (XRD), scanning electron mi
Mat. Res.. Publicado em: 2015-04
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14. Synthesis and physicochemical characterization of titanium oxide and sulfated titanium oxide obtained by thermal hydrolysis of titanium tetrachloride
This work reports the synthesis of titanium oxide (TiO2) and sulfated titanium oxide (TiO2-SO4(2-)) obtained by thermal hydrolysis of titanium tetrachloride. Titanium hydroxide synthesized by this method was impregnated with a 1 N H2SO4 solution, to give amounts of sulfate ions (SO4(2-)) of 3 and 7 wt%. The synthesized samples were dried at 120 °C during 24
Braz. J. Chem. Eng.. Publicado em: 2014-09
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15. Pulsed dc discharge in the presence of active screen for nitriding of high carbon steel
A discharge of nitrogen - hydrogen mixture by 50 Hz pulsed dc in the presence of active screen cage is investigated by optical emission spectroscopy (OES). The aim is to identify the parameters (mixture ratio, filling pressure and current density) that may lead to high concentration of active species (N2, N2+ and N). The maximum concentration in this experim
Mat. Res.. Publicado em: 22/07/2014
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16. Theoretical Optimal Trajectories for Reducing the Environmental Impact of Commercial Aircraft Operations
ABSTRACT: This work describes initial results obtained from an ongoing research involving the development of optimization algorithms which are capable of performing multi-disciplinary aircraft trajectory optimization processes. A short description of both the rationale behind the initial selection of a suitable optimization technique and the status of the op
J. Aerosp. Technol. Manag.. Publicado em: 2014-03
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17. Avaliação do ciclo de vida da areia em mineradora de pequeno porte, na região de São José do Rio Preto - SP / Life Cycle Assessment of sand in small mining in São José do Rio Preto region - São Paulo.
The mining of sand, although of great socio-economic importance to the national scene, has several negative impacts throughout the production chain. Among some of the interference in the natural environment occurs, soil degradation, air pollution and stress in the fauna and flora. This fact has generated great interest in mechanisms that mitigate or prevent
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 21/09/2012
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18. Resposta da cultura do milho aos fertilizantes fosfatados e nitrogenados revestidos com polímeros / Response of maize to polymer-covered phosphate and nitrogen fertilizers
The effective use of fertilizers, besides resulting in greater yield, can reduce production costs, with positive results in the end of the cropping season. Soil correction and fertilization in intensive maize production systems represent, on average, 40% to 45% of the production cost. Phosphorus is considered as a nutrient with low absorption by plants due t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/01/2012
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19. Optimization of diesel engine parameters using Taguchi method and design of evolution
The objective of this work is to optimize the control parameters of the direct injection (DI) single cylinder diesel engine with respect to NOx (Oxides of Nitrogen) and fuel emissions through experimental investigations and Taguchi method. A single cylinder 5.2 kW diesel engine was selected for this experiment. Five parameters such as clearance volume, valve
J. Braz. Soc. Mech. Sci. & Eng.. Publicado em: 2012-12
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20. Desenvolvimento de um sistema para detecção de dispersóides no ar
The amount of dust suspended in air can be harmful to human health if not complied with the limits previously established by the WHO (World Health Organisation). The air is polluted when it contains elements foreign to its natural composition: oxygen, nitrogen, noble gases and water vapor and even carbon dioxide. The most common forms of air pollution are ca
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/04/2011
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21. Síntese, Caracterização Estrutural e Propriedades Luminescentes de Complexos de Lantanídeos (III) com Hidrazonas e Semicarbazonas derivadas da 2,6-Diformilpiridina e com Triazenos 1-óxidos. / Synthesis, Structural Characterization and Luminescent Properties of Complexes of Lanthanides (III) with Hydrazones and Semicarbazones derived from 2,6-diformylpyridine and Triazenes 1-oxides.
Lanthanide complexes with ligands containing oxygen and nitrogen as donor atoms have been investigated in this study aiming to explore the coordinative behavior of metals with high coordination numbers, as well as a study of luminescence properties of new complexes. The chosen ligands were hydrazones and semicarbazones derived from 2,6-diformylpyridine and t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 201103
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22. Síntese e caracterização da difenil-4-amina sulfonato de cério (III) e sua aplicação como precursor do CeO2
The cerium oxide is a very useful material in a series of processes among which we highlight the automotive catalysts, where it acts as a regulator of oxygen. We studied the synthesis of complex diphenyl-4-amine sulfonate cerium (III) pentahydrate, Ce (C12H10NSO3) 3.5H2O, and its application as a precursor to the oxide CeO2. The complex was synthesized in aq
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/02/2011
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23. Synthesis and characterization of La1-xSr xMnO3±δ powders obtained by the polymeric precursor route
Polycrystalline strontium-doped lanthanum manganite (LSM) powders with 0.15, 0.22, and 0.30 mol % Sr were synthesized by the polymeric precursor route using a molar ratio of 3:1 citric acid and metal cations. The powders were characterized by Fourier transform infrared spectroscopy, thermal analysis, high-temperature X-ray diffraction to determine the crysta
Materials Research. Publicado em: 01/04/2011
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24. EXPERIMENTAL INVESTIGATION OF A DIESEL CYCLE ENGINE OPERATING ON DUAL-FUEL MODE: DIESEL / ETHANOL AND DIESEL / GAS / AVALIAÇÃO EXPERIMENTAL DE UM MOTOR DO CICLO DIESEL OPERANDO NO MODO BICOMBUSTÍVEL: DIESEL/ETANOL E DIESEL/GÁS
In this report, experimental tests of a Diesel cycle engine running with hydrous ethanol or natural gas with partial substitution for diesel fuel were performed. The main objectives were to verify the influence of alternative fuels and evaluate the advancing of diesel injection timing and the air partial restriction, regarding the characteristic parameters o
Publicado em: 2011