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951.
dos Anjos William Lima Morales Sergio Andres Villalba Oliveira Natália Maira Braga Valença Gustavo Paim 《Journal of Sol-Gel Science and Technology》2021,100(3):466-476
Journal of Sol-Gel Science and Technology - This work describes how the silica/alumina ratio (SAR) affects the framework, texture, chemical composition, and acidity of SAPO-34 molecular sieves... 相似文献
952.
Naji Al Dahoudi Amal AlKahlout Sabina Heusing Petra Herbeck-Engel Rudolf Karos Peter Oliveira 《Journal of Sol-Gel Science and Technology》2013,67(3):556-564
Crystalline indium doped zinc oxide (IZO) nanopowders were synthesized using hydrothermal treatment processing. Increasing the doping ratio of indium in the zinc oxide significantly influences the phase structure and shape of the nanopowders resulting in nanorod to nanoparticulate morphologies. As the doping profile increases, the crystallite size decreases, the band gap energy blue shifts and the specific surface area increases (measured by BET method). Additionally Raman spectroscopy exhibited shifts of several peaks, as well as revealed new peaks, confirming the substitution of indium ions within the zinc oxide lattice sites. An IZO suspension made of IZO nanoparticles (In/Zn = 3 atm.%) with a zeta potential greater than 30 mV at pH = 6 was successfully spin-coated on glass substrates for to make transparent conductive coatings evincing sheet resistances as low as 35 kΩ□ (ρ = 4.9 × 10?3 Ω m,) with transmission in the visible range as high as 90 %. 相似文献
953.
954.
Bruno Alves Rocha Marina Rezende Rodrigues Paula Carolina Pires Bueno Ana Rita de Mello Costa-Machado Mirela Mara de Oliveira Lima Leite Vaz Andresa Piacezzi Nascimento Hernane Silva Barud Andresa Aparecida Berretta-Silva 《Journal of Thermal Analysis and Calorimetry》2012,108(1):87-94
The propolis produced in Southeastern Brazil is known as green propolis (BGP) because of its color and the most important
plant source is Baccharis dracunculifolia. Several authors reported biological activities such as antiulcer, anti-inflammator, antimutagenic, antifungal/antibacterial,
antileishmanial/antiplasmodial for the BGP. For this reason, BGP has been extensively employed in food and beverages, thus
helping improve health and preventing diseases. Some authors related that the biological activities of BGP are mostly due
to its high levels of prenylated ρ-coumaric acids derivatives, mainly artepillin C. The inclusion complex between Brazilian
green propolis (BGP) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was prepared and its characterization was investigated by
different analytical techniques (X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetry) and suggesting
that propolis was molecularly dispersed in the HP-β-CD matrix. The increasing solubility of chemical constituents was determined
using quantitation methods for total flavonoids and polyphenols. Furthermore, it was developed a method for the quantitation
and identification of the main compounds by high-performance liquid chromatography in order to evaluate the increasing water
solubility of each constituent in aqueous BGP extract (aromadendrin, isosakuranetin, and artepillin C). The antioxidant activity
was evaluated by chemical assay 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging. 相似文献
955.
We offer a method of classification of spectral measures of discrete one-dimensional Schrödinger operators with respect to packing measures, which can be seen as dual to results for Hausdorff measures in subordinacy theory. We apply this method to classes of sparse operators, and give an example whose spectral measure has different Hausdorff and packing dimensions, and others for which such dimensions coincide. Some dynamical motivations are also mentioned. 相似文献
956.
da Silva Bruno Fonseca da Silva Karolayne Esthefany Melo de Farias Emerson Emiliano Gualberto de França Elvis Joacir Martins Mônica Cristina Barroso de Oliveira Santos Mariana Luiza de Lourdes Lacerda Buril Maria da Silva Alves Gustavo Gabriel de Oliveira Silva Andrezza Karla de Lira Júnior Ednaldo Barbalho da Silva Nicácio Herique Pereira Eugênia C. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3671-3679
Journal of Radioanalytical and Nuclear Chemistry - This study aimed to evaluate the effects of the Rn-222 progeny on the lichen Cladonia verticillaris under controlled conditions. The results... 相似文献
957.
Competition between unlimited and limited energy growth in a two-dimensional time-dependent billiard
Some dynamical properties for a dissipative time-dependent Lorentz gas are studied. We assume that the size of the scatterers change periodically in time. We show that for some combination of the control parameters the particles come to a complete stop between the scatterers, but for some other cases, the average velocity grows unbounded. This is the first time that the unlimited energy growth is observed in a dissipative system. Finally, we study the behavior of the average velocity as a function of the number of collisions and we show that the system is scaling invariant with scaling exponents well defined. 相似文献
958.
959.
960.
Daiane Cristina SassEmílio Carlos de Lucca Jr. Jader da Silva BarbosaKleber Thiago de Oliveira Mauricio Gomes Constantino 《Tetrahedron letters》2011,52(41):5371-5374
Conjugate reduction of ortho-substituted cinnamic esters by Stryker’s reagent to form copper enolates, followed by intramolecular aldol-type cyclization, successfully generated indane and tetralin rings in one pot efficiently. This tandem reaction is generally diastereoselective and provides good yields. 相似文献