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1.
Tsuchiya Letícia Diniz Braga Lucas Fiorini de Faria Oliveira Otávio de Bettio Raphael Winckler Greghi Juliana Galvani Freire André Pimenta 《Personal and Ubiquitous Computing》2021,25(2):281-295
Personal and Ubiquitous Computing - This article presents a study concerning the evaluation of a smart home control system for elderly people with a sample of 10 users in a city in the interior of... 相似文献
2.
In this work we investigated the mechanism of the electrochemical intercalation reactions in rf sputtered nickel oxide thin films electrodes by two techniques: mechanical stress change measurements by means of an optical technique and mass changes using an electrochemical quartz microbalance (EQCM). The experiments were performed in alkaline electrolytes containing cations of the first column of the periodic table. Reversible mass and volume changes were observed. In order to explain these experimental results, an exchange reaction is proposed, in which the oxidation process is accompanied by the deinteractional of a relative large number of “light” cations, simultaneously with the intercalation of a smaller number of heaviest cations. 相似文献
3.
Sandra Aparecida de Assis Pedro Fernandes Bruno Sommer Ferreira Joaquim MS Cabral Olga Maria Mascarenhas Faria Oliveira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):277-280
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry 相似文献
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Catalytic wet air oxidation of butyric acid solutions using carbon-supported iridium catalysts 总被引:1,自引:0,他引:1
Aqueous solutions of butyric acid were treated by catalytic wet air oxidation using carbon-supported iridium catalysts in a stirred reactor. Under the operating conditions of 6.9 bar of oxygen partial pressure and 200 °C of temperature, conversions up to 52.9% after 2 h were obtained depending on the type of catalyst used. The effects of butyric acid initial concentration, loading of catalyst, oxygen partial pressure and temperature were investigated and the empirical rate law for acid conversion is presented. Oxidation intermediates such as propionic and acetic acid were identified. The heterogeneous catalyzed free-radical oxidation of butyric acid is discussed. 相似文献
6.
Au-based catalysts, known for ambient temperature CO oxidation, have to provide stable performance of up to 5000 h in order to be commercially applicable in automotive fuel cells. In this report, the on-line deactivation characteristics of Au/TiO2 in unconventional PROX conditions are discussed. As opposed to CO removal from air, results in this report suggests that carbonates have a minor effect on deactivation of Au/TiO2 in dry H2-rich conditions. Also, no conclusive correlation between surface hydration and deactivation was observed. Rather, deactivation appeared to have occurred as a result of an intrinsic transformation in the oxidation state of the active species in the reducing operating conditions; a process which was reversible in an oxidizing atmosphere. 相似文献
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Jairo Rocha de Faria Antonio A. Novotny 《Structural and Multidisciplinary Optimization》2009,39(6):547-555
The topological derivative provides the sensitivity of a given shape functional with respect to an infinitesimal (non smooth)
domain perturbation at an arbitrary point of the domain. Classically, this derivative comes from the second term of the topological
asymptotic expansion, dealing only with infinitesimal perturbations. However, for practical applications, we need to insert
perturbations of finite size. Therefore, we consider one more term in the expansion which is defined as the second order topological
derivative. In order to present these ideas, in this work we calculate first as well as second order topological derivatives
for the total potential energy associated to the Laplace’s equation, when the domain is perturbed with a hole. Furthermore,
we also study the effects of different boundary conditions on the hole: Neumann and Dirichlet (both homogeneous). In the Neumann’s
case, the second order topological derivative depends explicitly on higher-order gradients of the state solution and also
implicitly on the point where the hole is nucleated through the solution of an auxiliary problem. On the other hand, in the
Dirichlet’s case, the first order topological derivative depends explicitly on the state solution as well as implicitly through
the solution of an auxiliary problem, and the second order topological derivative depends only explicitly on the solution
associated to the original problem. Finally, we present two simple examples showing the influence of both terms in the second
order topological asymptotic expansion for each case of boundary condition on the hole. 相似文献
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10.
Vitor A. Figueiredo Antonio Lobato de Faria Stephen D. Myers Artur Ascenso Pires 《国际水》2013,38(1):13-17
ABSTRACT The continuous increase in water demand for various uses underlines the importance of supply problems in the general context of water resources management. In this domain it would clearly be useful to collect and make available all the data currently stored on different paper supports and kept by several regional agencies. This would provide an immediate overview of tbe resources, and also permit forecasting the future demand for tbe various utilizations. This paper describes a project involving a database to be used for groundwater resources management, conceived not only as a support for research activity, but also as a contribution to developing new and more efficient managementprocedures. The database has been designed to be used on a personal computer, with software readily available on the market. 相似文献