Ethane
Mostrando 13-24 de 230 artigos, teses e dissertações.
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13. Low-energy electron collisions with ethane
We employed the Schwinger multichannel method to compute elastic cross sections for low-energy electron collisions with ethane (C2H6). The calculations were carried out in the static-exchange and static-exchange plus polarization approximations for energies up to 12 eV. Our integral cross section shows good agreement with experimental data and with theoretic
Brazilian Journal of Physics. Publicado em: 2009-03
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14. Studies on mixed metal oxides solid solutions as heterogeneous catalysts
In this work, a series of perovskite-type mixed oxide LaMo xV1-xO3+δ powder catalysts (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, and 1.0, with 0.5 < δ < 1.5), prepared by the sol-gel process and calcined at 750ºC, provide an attractive and effective alternative means of synthesizing materials with better control of morphology. Structures of resins obtained during t
Brazilian Journal of Chemical Engineering. Publicado em: 2009-03
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15. Highly selective transport of mercury(II) ion through a bulk liquid membrane
In this work carrier-facilitated transport of mercury(II) against its concentration gradient from aqueous 0.04 M hydrochloric acid solution across a liquid membrane containing isopropyl 2-[(isopropoxycarbothiolyl)disulfanyl]ethane thioate (IIDE) as the mobile carrier in chloroform has been investigated. Sodium thiocyanate solution (1.6 M) was the most effici
Química Nova. Publicado em: 2009
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16. Filtro a base de nanofibras de carbono para sequestro de enxofre em efluentes gasosos ricos em H2S / Carbon nanofibers based filter to sulfur removal from efluents rich in H2S.
Over the last few decades, sulfur recovery from the H2S-containing acid gases have become more and more important due to the ever increasing standards of efficiency required by environmental protection measures. The general trend is to selectively transform H_2S into elemental sulfur which is a valuable product, by the modified Claus process. However, due to
Publicado em: 2009
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17. Carbon nanofibers: a versatile catalytic support
The aim of this article is present an overview of the promising results obtained while using carbon nanofibers based composites as catalyst support for different practical applications: hydrazine decomposition, styrene synthesis, direct oxidation of H2S into elementary sulfur and as fuel-cell electrodes. We have also discussed some prospects of the use of th
Materials Research. Publicado em: 2008-09
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18. Determinação de hidrocarbonetos majoritarios presentes no gas natural utilizando espectroscopia no infravermelho proximo e calibração multivariada / Determination of major hydrocarbons in natural gas using near infrared spectroscopy and chemometrics
Near Infrared (NIR) Spectroscopy and Chemometrics were used to construct calibration models to determine the concentration of major hydrocarbons in gas mixtures in concentrations similar to those observed in natural gas. The spectra were obtained by two different NIR spectrophotometers made in the laboratory, one employing a cell of fixed and other with vari
Publicado em: 2008
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19. Unusual coordination of tetraphenylborate to silver(I): synthesis and X-ray crystal structure of the complex N,N'-bis[3-(2-nitrophenyl)allylidene]ethane-1,2 diamine(tetraphenylborato)silver(I)
O complexo N,N’-bis[3-(2-nitrofenil)alilideno]etano-1,2-diamino(tetrafenilborato)prata(I), [Ag(nca2en)(BPh4)], foi sintetizado e caracterizado por análise elementar e por espectroscopias de RMN de ¹H, de absorção no infravermelho e UV-vis. Sua estrutura cristalina e molecular foi determinada por difratometria de raios X (monocristal). O centro de prata
Journal of the Brazilian Chemical Society. Publicado em: 2008
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20. Avaliação da performance de motor a combustão interna e suas emissões utilizando biogasolina do craqueamento térmico de gorduras residuais
With the growing demand for fossil fuel and the need to minimize greenhouse gases emissions, investigative studies have been developed to allow the implementation of technologies that produce alternative fuels, with special emphasis for those developed from esterification/transesterification and catalytic cracking processes. The quality of the resulting prod
Publicado em: 2008
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21. Development and application of the pulse train hyper-Rayleigh scattering technique. / Desenvolvimento e aplicação da técnica de hiper Rayleigh com trem de pulsos
This thesis reports an extension of the Hyper-Rayleigh scattering technique (HRS) and its application to study the mechanisms that contribute to the molecular first hyperpolarizabilities (). We use a Nd:YAG laser, Q-switched and mode-locked, as pumping beam to excite the samples. The laser delivers 100 ps pulses modulated by a Q-switch envelope, and the outp
Publicado em: 2008
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22. Adsorption equilibrium of light hydrocarbon mixtures by monte carlo simulation
The procedure presented by Cabral et al. (2003) was used to predict the adsorption of multicomponent mixtures of methane, ethane, propane, and n-butane adsorbed on Silicalite S-115 at 300 K. The methodology employed uses the algorithm of molecular simulation for the grand canonical ensemble as an equation of state for the adsorbed phase. The adsorbent surfac
Brazilian Journal of Chemical Engineering. Publicado em: 2007-12
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23. 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
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24. "O estudo da utilização do gás natural como insumo para a indústria química e petroquímica: modelagem de uma planta gás-química" / The study of the use of natural gas as a feedstock for the chemical and petrochemical industry: the modeling of a gas-chemical plant.
Este trabalho tem como objetivo apresentar, através da modelagem de uma planta gásquímica e da identificação das tecnologias disponíveis, a versatilidade do uso do gás natural como insumo para a indústria química, visando à produção de metanol, amônia e hidrogênio, a partir da fração metano, bem como na indústria petroquímica a obtenção d
Publicado em: 2007