Mcm 41
Mostrando 13-24 de 111 artigos, teses e dissertações.
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13. CERIUM INCORPORATED INTO A MESOPOROUS MOLECULAR SIEVE (MCM-41)
Abstract The synthesis and characterization of a mesoporous molecular sieve (MCM-41) was studied due to its high surface area and large pore volume and to target potential applications in adsorption and catalysis. Rare earth elements have special chemical properties and are efficient promoters for supports. In this study, a mesoporous molecular sieve that in
Braz. J. Chem. Eng.. Publicado em: 2016-09
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14. COMPARATIVE STUDY OF THE PHYSICOCHEMICAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF MODIFIED MCM-41 SYNTHESIZED BY DIRECT (ONE-STEP) INCORPORATION AND IMPREGNATION
MCM-41 structures were synthesized and modified by direct (one-step) incorporation (DI) and wet impregnation (WI) methods. The solids were characterized by XRF, XRD, N2 adsorption and UV-Vis DR, and catalytically evaluated in the Acid Orange 7 (AO7) degradation under visible light. Significant influence of the presence, dispersion and location of the differe
Quím. Nova. Publicado em: 2016-06
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15. SÍNTESE E PROPRIEDADES DE SÍLICAS HÍBRIDAS CONTENDO SURFACTANTES CETILTRIALQUILAMÔNIO
This work presents the synthesis of silicas containing cetyltrialkylammoniun surfactants in their mesopores. Initially, the aqueous dispersions of these surfactants were characterized by small-angle X-ray scattering (SAXS). The hybrid silicas obtained from these dispersions were evaluated by X-ray diffractometry (XRD) and nitrogen physisorption. The XRD show
Quím. Nova. Publicado em: 2016-04
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16. Efeito de diferentes fontes de sílica nos parâmetros texturais da peneira molecular MCM-41
Resumo Nas últimas décadas, pesquisas estão sendo desenvolvidas para obtenção de materiais eficientes e economicamente viáveis para aplicação em diversos setores da indústria. Os materiais mesoporosos da família MCM-41 estão entre os candidatos eficazes pela facilidade de síntese e estrutura que favorece uma gama de aplicações. O objetivo desse
Cerâmica. Publicado em: 2016-03
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17. Synthesis Optimization of MCM-41 for CO2 Adsorption Using Simplex-centroid Design
There is a growing concern on the relationship between anthropogenic carbon dioxide and climate changes. A promising approach is the adsorption technology using mesoporous MCM-41 materials that can be easily synthesized to depict structures adequate to the flow of gas. The aim of this study was to improve the synthesis of MCM-41 using cationic surfactant mix
Mat. Res.. Publicado em: 2015-08
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18. Metal-Modified Mesoporous Silicate (MCM-41) Material: Preparation, Characterization and Applications as an Adsorbent
Mesoporous silicate (MCM-41) materials, modified with CuII, FeIII or AlIII were prepared by a hydrothermal method and were characterized by nitrogen adsorption at 77 K, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), temperature programmed re
J. Braz. Chem. Soc.. Publicado em: 2015-08
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19. MCM-41 for Meloxicam Dissolution Improvement:
in vitro Release and in vivo Bioavailability StudiesIn this study, MCM-41 was prepared as a carrier for poorly water soluble drugs. Meloxicam (MLX) was selected as model compound. Textural and chemical characterizations were carried out by thermal gravimetric analysis (TGA), scanning electron microscope (SEM), nitrogen adsorption/desorption, X-ray diffraction (XRD) and Fourier transform infrared (FTIR). Th
J. Braz. Chem. Soc.. Publicado em: 2015-07
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20. VAPOR-PHASE CATALYTIC CONVERSION OF ETHANOL INTO 1,3-BUTADIENE ON Cr-Ba/MCM-41 CATALYSTS
AbstractAl-MCM-41, 16%Ba/Al-MCM-41 and 1.4%Cr-16%Ba/Al-MCM-41 were used as catalysts in the vapor-phase catalytic conversion of ethanol. Physical-chemical properties of the catalysts and the effect of barium and chromium on the Al-MCM-41 activity and 1,3-butadiene yield were studied. The catalysts were characterized by X-ray diffraction (XRD), N2 physisorpti
Braz. J. Chem. Eng.. Publicado em: 2015-06
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21. Comparison of Kinetic Study of CTMA+ Removal of Molecular Sieve Ti-MCM-41 Synthesized with Natural and Commercial Silica
This work aimed to determine and compare the apparent activation energy, involved in thermal decomposition of CTMA+ from the pores of Ti-MCM-41 synthesized by two different source of silica in order to evaluate their influence in the template removal. The molecular sieves Ti-MCM-41 were synthesized using rice husk ash (RHA), as alternative low cost source of
Mat. Res.. Publicado em: 2015-06
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22. DESENVOLVIMENTO DE MATERIAIS HÍBRIDOS MICRO-MESOPOROSOS DO TIPO ZSM-12/MCM-41
Micro-mesoporous hybrid materials of ZSM-12/MCM-41 type with different micro- and mesoporosity contributions were prepared by a procedure that uses the desilication of the zeolite in an alkaline medium, followed by recrystallization onto the mesostructure, where the zeolite is used as the silica source in the formation of mesoporous phase. The materials were
Quím. Nova. Publicado em: 2015-03
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23. Potencial de óleos essenciais de plantas medicinais no controle de fitopatógenos
Além do valor como recurso terapêutico, plantas medicinais também possuem potencial para serem utilizadas como fonte de princípios ativos contra fitopatógenos. O objetivo deste trabalho foi avaliar o efeito de óleos essenciais das espécies medicinais Baccharis dracunculifolia (alecrim-do-campo), Schinus terebinthifolius (aroeirinha) e Porophyllum rude
Rev. bras. plantas med.. Publicado em: 2015-03
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24. Influence of Temperature and Time of Seed Aging on the Properties of Beta Zeolite/MCM-41 Materials
As restrições de difusão dos reagentes, causadas pelos microporos, limitam a utilização de zeólitas no processamento de moléculas volumosas. Isto exige o desenvolvimento de materiais que combinem as propriedades das zeólitas com aquelas dos materiais mesoporosos. Com este objetivo, neste trabalho, estudou-se a influência da temperatura e do tempo de
J. Braz. Chem. Soc.. Publicado em: 2014-12