Navegando por Data de Publicação, começando com "2007-08-28"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 3 de 3

Perovskitas La1-xSrxMnO3, suportadas em alumina e zircônia, aplicadas à combustão do metano
(Universidade Federal de São Carlos, 2007-08-28) Santos, Lidiane Faria; Assaf, José Mansur; https://lattes.cnpq.br/9563312407691130; https://lattes.cnpq.br/6141017395528482
The total oxidation of the methane is an important environmental and industrial reaction, mainly because it is extensively used in energy production and in the control of gases emission to the atmosphere. With catalysts, the methane combustion is available at lower temperatures, thus decreasing the emission of NOx, a gas of green house harmful to human health. Perovskite-type oxides of the series La1-xSrxMnO3 (x = 0, 0,3 e 0,5) supported on γ-Al2O3 and ZrO2 were prepared and characterized for application in methane oxidation. The samples were prepared by co-precipitation and depositionprecipitation methods, using aqueous solutions of metals nitrates and urea as precipitant agent. Each catalysts were calcined in two steps: first at 600 ºC for 5 hours and later in one of these conditions: 700 ºC/10 h, 800 ºC/10 h or 900 ºC/10 h. Chemical analysis, X-Ray Diffraction (XRD), Specific Surface Area (BET), Temperature Programmed Reduction (TPR) and Scanning Electron Microscopy (SEM) were applied to characterize the samples. The XRD spectra showed that the crystalline structures of the unsupported La1-xSrxMnO3 perovskite were best defined with the increase of the calcination temperature. On the other hand, in the supported samples the complete visualization of the XRD spectra was difficult, being the perovskite structure just confirmed by the presence of its more intense peak. As La3+ and Sr2+ do not reduce at the experimental conditions applied in this work, all the peaks showed in TPR analysis corresponding to reduction of the species Mnn+. The influence of the calcination temperature can also be observed in the variation of the specific surface area of the catalysts. The catalytic essays showed that the compounds are actives at relatively low temperature. The supported catalysts presented higher activity than the unsupported ones and the calcined at lower temperature showed more satisfactory catalytic activities. The substitution of La by Sr increased significantly the catalytic activity of the studied systems
Procedimentos para o processo de planejamento da construção : estudo de caso, São Carlos, Estado de São Paulo.
(Universidade Federal de São Carlos, 2007-08-28) Moraes, Rosa Maria de Mattos; Serra, Sheyla Mara Baptista; https://lattes.cnpq.br/8528385567782505
The competitiveness at the civil construction companies segment depends on the management efficient of its planning and execution control systems. The construction planning through more efficient models it's leaving of being an ideal to be a reality in some companies, as a strategy for quality improvement of its products and the competitiveness increase in their market. This research is focused on the building planning system improvement, with emphasis in building programming and control, through the use of computational tools, aiming, in special, the segment of multi-story buildings. The objective is to present systematic and usual procedures in the planning process of the construction. The implementation of the planning process is demonstrated through a case study, which considers since the stage of building program conception up to the execution control, performed through the building follow-up. The result of this research is the presentation of an easily implemented planning process for the segment of multi-story building companies, which generate quick information to support decisions.
Processo de engenharia de domínio para aplicações em cadeias de suprimentos que utilizam de identificação por radiofreqüência (RFID)
(Universidade Federal de São Carlos, 2007-08-28) Campos, Leonardo Barreto; Zorzo, Sérgio Donizetti; https://lattes.cnpq.br/2523715806470871; https://lattes.cnpq.br/5550218769434638
The Radio Frequency Identification RFID has opened a new phase in Supply Chain Management that can be controlled with precision and agility. Through this new technology is possible that Supply Chain members exchange informations in real time about stock, replace request, location of the products, and business strategy. However, the Radio Frequency Identification do not considered by software reuse and component-based development processes. In this sense, the Domain Engineering presents one solution to collecting, organizing, and storing past experience in building news systems used to reduce costs in RFID-based software development. Thus, this work presents an Domain Engineering Process based on a well defined set of guidelines and steps to RFID-based software engineering Systems in Supply Chain. We showed as results three Domain Engineering phases and one study case of the Supermarket Supply Chain.