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71.
72.
Whei Oh Lin Edson de Souza Coutinho 《Monatshefte für Chemie / Chemical Monthly》1983,114(11):1231-1235
The title compounds are obtained directly on reaction of 6-chloroacetamidopiperonal with substituted phenylhydrazines. Piperonal was used as starting material. 相似文献
73.
Tatiane M. Arantes Giovanni P. Mambrini Daniel G. Stroppa Edson R. Leite Elson Longo Antonio J. Ramirez Emerson R. Camargo 《Journal of nanoparticle research》2010,12(8):3105-3110
Nanocrystalline zirconium oxide was synthesized by hydrothermal treatment of ZrO(NO3)2 and ZrOCl2 aqueous solutions at different temperatures and time in presence of hydrogen peroxide. Hydrothermal treatment of zirconium salts (0.25 and 0.50 mol L?1) produced nanocrystalline monoclinic ZrO2 powders with narrow size distribution, which were formed by the attachment of the smaller particles with crystallites size of 3.5 nm, estimated by means of the Scherrer’s equation and confirmed by transmission electronic microscopy. Typical monoclinic zirconium oxide X-ray powder diffraction patterns and Raman spectra were obtained for all the crystalline powders. It was observed that the crystallization depends strongly on the temperature, resulting in amorphous material when the synthesis was realized at 100 °C, and crystalline with monoclinic phase when synthesized at 110 °C, independently of the salt used. Zirconium oxide colloidal nanoparticles were formed only at hydrothermal treatments longer than 24 h. The stability of the colloids was successfully characterized of zeta potential, showing an initial value of + 59.2 mV in acid media and isoelectric point at pH = 5.2, in good agreement with previous studies. 相似文献
74.
J. Barba-Ortega Edson Sardella J. Albino Aguiar 《Physica C: Superconductivity and its Applications》2010,470(21):1964-1967
Nonlinear time-dependent Ginzburg–Landau (TDGL) equations were solved in the present work using the link variables method. Vortex configurations were investigated in a superconducting circular sector immersed in an external magnetic field applied perpendicular to its plane. Magnetization and free energy were calculated as a function of the applied magnetic field at several temperatures. This paper illustrates how the vortices moved around at the transition fields before they become accommodated into an equilibrium configuration. A linear dependence of the magnetization dependence on temperature has been found for a certain magnetic field. 相似文献
75.
Evernice Chikukwa Edson Meyer Johannes Mbese Nyengerai Zingwe 《Molecules (Basel, Switzerland)》2021,26(14)
The drawbacks of utilizing nonrenewable energy have quickened innovative work on practical sustainable power sources (photovoltaics) because of their provision of a better-preserved decent environment which is free from natural contamination and commotion. Herein, the synthesis, characterization, and application of Mo chalcogenide nanoparticles (NP) as alternative sources in the absorber layer of QDSSCs is discussed. The successful synthesis of the NP was confirmed as the results from the diffractive peaks obtained from XRD which were positive and agreed in comparison with the standard. The diffractive peaks were shown in the planes (100), (002), (100), and (105) for the MoS2 nanoparticles; (002), (100), (103), and (110) for the MoSe2 nanoparticles; and (0002), (0004), (103), as well as (0006) for the MoTe2 nanoparticles. MoSe2 presented the smallest size of the nanoparticles, followed by MoTe2 and, lastly, by MoS2. These results agreed with the results obtained using SEM analysis. For the optical properties of the nanoparticles, UV–Vis and PL were used. The shift of the peaks from the red shift (600 nm) to the blue shift (270–275 nm and 287–289 nm (UV–Vis)) confirmed that the nanoparticles were quantum-confined. The application of the MoX2 NPs in QDSSCs was performed, with MoSe2 presenting the greatest PCE of 7.86%, followed by MoTe2 (6.93%) and, lastly, by MoS2, with the PCE of 6.05%. 相似文献
76.
Issa JP Spadaro AC Bentley MV Iyomasa MM Siéssere S Regalo SC Defino HL 《Micron (Oxford, England : 1993)》2008,39(7):952-959
The purpose of this work was to evaluate the new bone tissue, comparing two different carriers for rhBMP-2, monoolein and chitosan gels, using the decortication and nondecorticatication surgical technique in rat mandibles, evaluated by histomorphometrical method. It was used 56 male Wistar rats (300g), divided into 8 groups according to the rhBMP-2 carrier used, monoolein or chitosan gels; surgical technique, bone decortication or nondecortication; and period of time, 3 or 6 weeks until the sacrifice by perfusion. Results obtained in this study showed that the rhBMP-2/monoolein and rhBMP-2/chitosan used in this experimental model was able to induce osteogenesis, contributing to the bone healing process. The bone repair process was time dependent, so that at 6 weeks there was an improved amount of new bone in relation to 3 weeks, considered each analyzed group, and the decortication was able to expose the bone marrow and speed up the bone healing process, which was showed by histomorphometrical methods. Both of carriers were capable to adapt to the bone surgical area, according to the clinical observations, and had favorable properties in relation to protein releasing, revealed by the amount of new bone tissue found in the histological analysis. 相似文献
77.
Lianet Aguilera Priscila Carvalho Machado Aguiar Yurimiler Leyet Eduardo Padrón-Hernández Raimundo Ribeiro Passos Leandro Aparecido Pocrifka 《Journal of Solid State Electrochemistry》2018,22(12):3845-3852
In the present work, CoOOH films are synthesized from the electrochemical oxidation of α-Co(OH)2 as precursor. The substrate influences on the material electrochemical properties are studied. The samples are structural and morphologically characterized using techniques of X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy techniques are used for the electrochemical characterization. The films deposited on steel substrate grew in the vertical hexagonal platelet form. Meanwhile, films on Ti plate presented morphology in agglomerated sphere form. After electrochemical oxidation, the film initial morphology is maintained. The films deposited on steel plate have a structure which favors charge storage showing a high specific capacity value (110.92 mA h g?1) and cyclic stability of 92% after 1000 cycles. Finally, the relaxation time constant value calculated was 5.6 s. This fact is making this material as a possible good candidate for application as electrode material or additive for other materials, in energy storage devices. 相似文献
78.
J. Edson Sampaio 《Selecta Mathematica, New Series》2016,22(2):553-559
We prove that if there exists a bi-Lipschitz homeomorphism (not necessarily subanalytic) between two subanalytic sets, then their tangent cones are bi-Lipschitz homeomorphic. As a consequence of this result, we show that any Lipschitz regular complex analytic set, i.e., any complex analytic set which is locally bi-Lipschitz homeomorphic to an Euclidean ball must be smooth. Finally, we give an alternative proof of S. Koike and L. Paunescu’s result about the bi-Lipschitz invariance of directional dimensions of subanalytic sets. 相似文献
79.
We prove that two C
3 critical circle maps with the same rotation number in a special set ? are C
1+α conjugate for some α>0 provided their successive renormalizations converge together at an exponential rate in the C
0 sense. The set ? has full Lebesgue measure and contains all rotation numbers of bounded type. By contrast, we also give examples
of C
∞ critical circle maps with the same rotation number that are not C
1+β conjugate for any β>0. The class of rotation numbers for which such examples exist contains Diophantine numbers.
Received November 1, 1998 / final version received July 7, 1999 相似文献
80.