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排序方式: 共有512条查询结果,搜索用时 15 毫秒
1.
Josepha Yohanna de Jesus Eliane Santos de Carvalho Dantas Mairim Russo Serafini Paula dos Passos Menezes Juliana Cordeiro Cardoso Ricardo Luiz Cavalcanti Albuquerque-Jr Jivaldo do Rosário Matos Juliana Ferreira de Oliveira Irwin Rose Alencar de Menezes Francilene Amaral da Silva Adriano Antunes de Souza Araújo 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2003-2012
2.
Lisboa Thalles Pedrosa de Faria Lucas Vincius Alves Guilherme Figueira Matos Maria Auxiliadora Costa Matos Renato Camargo 《Journal of Solid State Electrochemistry》2021,25(8):2301-2308
Journal of Solid State Electrochemistry - This work describes a simple, rapid, and cost-effective method for fabrication of paper-based carbon electrode (US$ <0.01) using conductive ink... 相似文献
3.
Antônio Gomes dos Santos Neto Franciele de Matos Morawski Ana Caroline Ferreira Santos Cláudia Quintino da Rocha Roberto Batista de Lima Marília Oliveira Fonseca Goulart Clenilton Costa dos Santos Flávio Colmati Antônio Euzébio Goulart Santana Marco Aurélio Suller Garcia Auro Atsushi Tanaka 《Electroanalysis》2023,35(5):e202200390
Here, we report multiwalled carbon nanotubes (MWCNTs) functionalized with γ-cyclodextrins (γCD) as a novel electrochemical strategy for Rutin determination, showing superior performance than β-cyclodextrins (βCD) modified MWCNTs, suggesting an adequate environment for host-guest interactions. Under optimized conditions, the sensor showed a linear range of 39–975 nmol L−1 and a limit of detection of 7 nmol L−1. When tested with quercetin, catechin, and caffeine, the platform presented high selectivity with an interference response <10 %. The method was employed to quantify Rutin in spiked pharmaceutical and herbal extracts, providing recovery of 93–98.4 %. Also, HPLC-PDA confirmed the method‘s accuracy. 相似文献
4.
Reis Thaiene A. Matos Breno N. Lima Eliana M. Chaker Juliano A. Gratieri Tais Cunha-Filho Marcílio S. S. Gelfuso Guilherme M. 《Journal of Thermal Analysis and Calorimetry》2017,128(3):1671-1682
Journal of Thermal Analysis and Calorimetry - The objectives of this study were to verify the viability of the photoinitiating system using curcumin as a photoinitiator and glycerol as a... 相似文献
5.
J. C. P. Pina A. M. Dias P. F. P. de Matos P. M. G. P. Moreira P. M. S. T. de Castro 《Experimental Mechanics》2005,45(1):83-88
In this paper we present the methods of determination and the stress obtained at the periphery of a cold expanded hole in
a 2024-T3 Alclad aluminum alloy sheet. The measurements in the aluminum clad were performed by the sin2Ψ method, taking experimental precautions to deal with the texture effects. In the core aluminum a special method had to be
implemented to determine the stress values in a direction not accessible to the X-ray diffraction. The strains were measured
in sample orientations selected according to the texture characteristics and stress factorsF
ij
were used to calculate the stress tensor. TheF
ij
values were determined assuming a quasi-isotropic material behavior, after concluding that the stress results were not significantly
affected by factors calculated for textured material. The residual stress profile, both in the clad and in the sheet, shows
a nearly axisymmetric stress state. Compressive stresses were observed near the periphery of the hole, with values that are
higher on the exit than on the entrance face. Residual stresses were also higher in the hoop direction than in the radial
direction. They decreased with the radial distance to the hole and affected the previous stress state over a distance of 6
mm. The plastic deformation induced by the cold expansion is well evidenced by the FWHM values, which in the affected zone
decrease with increasing distance from the hole edge. 相似文献
6.
José Roberto dos Santos Politi Paulo Roberto Rodrigues de Matos Maria José Araújo Sales 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1437-1442
Demand for lubricating oils is increasing in the growing Brazilian economy. The use of vegetable bases in exchange of minerals can bring socio-economic and environmental benefits for Brazil. The purpose of this study is to compare the thermal and oxidative stability of vegetable oils related to the bases commonly used as lubricants. In this study, thermogravimetric analysis of castor oil, cotton oil, macauba’s almond oil, passion oil, paraffinic mineral oil, naphthenic oil (NH-140) and synthetic oil (Etro) was performed in inert and oxidative atmosphere to study the thermal and oxidative degradation of the vegetable oils related to the most common lubricants’ oils base. These oils’ oxidation stability were determined by standard procedures (ISO 6886). The use of mineral oil’s additives in these vegetable oils was tested to verify the viability of these additives to improve the oxidative stability of the vegetable oils. The castor oil and the cotton oil presented results of thermal analysis similar to the mineral and synthetic bases values. The castor oil was the only vegetable oil that showed a great oxidative stability. All other vegetable oils had their oxidative stability significantly increased by the additives. 相似文献
7.
R. L. Grosso J. R. Matos E. N. S. Muccillo 《Journal of Thermal Analysis and Calorimetry》2014,117(2):567-572
Zirconia containing 10 mol% scandia and x mol% dysprosia (0 ≤ x ≤ 1.5) gels was synthesized by simultaneous precipitation at room temperature. The aim of this work is to verify the effect of dysprosium on the cubic phase stabilization of the zirconia–scandia solid electrolyte. The gel was characterized by thermogravimetry, differential scanning calorimetry, and differential thermal analyses. The thermally treated powders were analyzed by Fourier transform infrared spectroscopy, thermal analyses, and X-ray diffraction techniques. For comparison purpose, a commercial zirconia–10 mol% scandia powder was subjected to some characterization techniques. The infrared spectrum shows characteristic absorption bands due to residual material from the synthesis on the surface of the powder particles. Nanostructured powders were obtained after thermal treatments at 500 °C for 2 h. Infrared spectroscopy and X-ray diffraction results evidence the stabilization of the cubic phase in zirconia–scandia containing dysprosium. The thermal stability of the cubic phase during thermal cycling was ascertained by thermal analysis. 相似文献
8.
Frontispiece: Enantioselective Organocatalytic Cascade Approach to Different Classes of Benzofused Acetals 下载免费PDF全文
9.
10.
Vitor Matos Julio D. Silva Dan Marchesin 《Bulletin of the Brazilian Mathematical Society》2016,47(2):545-559
Themain goal of ourwork is to showthat there exists a class of 2×2 Riemann problems for which the solution comprises a singlewave group for an open set of initial conditions. This wave group comprises a 1-rarefaction joined to a 2-rarefaction, not by an intermediate state, but by a doubly characteristic shock, 1-left and 2-right characteristic. In order to ensure that perturbations of initial conditions do not destroy the adjacency of the waves, local transversality between a composite curve foliation and a rarefaction curve foliation is necessary. 相似文献