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Puebla de Zaragoza, Mexico

Petranovskii V.,National Autonomous University of Mexico | Espinosa M.A.H.,BUAP | Kolobova E.,Tomsk Polytechnic University | Pestryakov A.,Tomsk Polytechnic University
Advanced Materials Research | Year: 2014

By selective acid leaching, silica nanotubes were prepared from the natural mineral chrysotile asbestos. These one-dimensional tube actually represent a convolution of two-dimensional layers, and the subsequent stacking the tubes into a hexagonal assembly generates three-dimensional body. Made materials are acid- and heat-resistant and can be used as feedstock in the manufacture of filters, or as matrices for the synthesis of nanomaterials. © (2014) Trans Tech Publications, Switzerland.

Silva Ortigoza R.,Cidetec | Marcelino-Aranda M.,UPIICSA IPN | Silva Ortigoza G.,BUAP | Hernandez Guzman V.M.,UAQ | And 4 more authors.
IEEE Latin America Transactions | Year: 2012

Robotics is a fast developing and exciting field with multiple applications which span from robot manipulators to mobile robots. This paper presents a literature review on wheeled mobile robots. We point out the main considerations to be taken into account when designing this class of robots. The main control problems are recalled as well as the corresponding solutions. Finally, we summarize the most important approaches used to render mobile robots autonomous. © 2003-2012 IEEE.

Carbajal-Gomez V.H.,National Institute of Astrophysics, Optics and Electronics | Tlelo-Cuautle E.,National Institute of Astrophysics, Optics and Electronics | Trejo-Guerra R.,Semtech | Munoz-Pacheco J.M.,BUAP
Proceedings - IEEE International Symposium on Circuits and Systems | Year: 2013

This investigation shows the modeling and simulation of the synchronization of two multi-scroll chaotic oscillators in a master-slave topology. The synchronization is performed by Generalized Hamiltonian forms and observer approach from nonlinear control theory. The case of study consists of two 4-scroll attractors based on saturated function series. Finally, the numerical simulation of the synchronization, from the mathematical description, and the circuit implementation using HSPICE models of opamps, show the good agreement between theory and experiment results. © 2013 IEEE.

Bautista-Rodriguez C.M.,Grupo Mexico | Rosas-Paleta M.G.A.,Grupo Mexico | Tepale-Ochoa N.,BUAP | Sanchez-Grijalva D.,Grupo Mexico
International Journal of Electrochemical Science | Year: 2012

The PEMFC technology is considered as an applicable technology to portable and transportable services; however its application in stationary service has been widely questioned as a viable proposition. This paper develops a FEL study type 1 for a domestic electrical service design. 3 PEMFC prototypes were scaled and compared to supply a stationary domestic electrical service. The integrated method was applied to determine the cost of the technology and the total investment cost +/- 50% at 20 years of useful life for each prototype. Operating costs were estimated considering the consumption of hydrogen from a material balance. It was also developed a cost estimate for electrical production in each case. Finally, a simple method for a risk analyze was developed for this conceptual project. The results show the effect of the cost of materials selected for PEMFC assembly on investment costs and operating costs. This effect is also observed on the production cost when cathodic pressure is applied below 10 psi; however at higher pressures the production cost is influenced by the combination between efficiency of PEMFC assembly and its materials cost. The electrical production costs obtained by PEMFC technology are close at sold price in some regions on the world. This result permits to considerate the PEMFC application in stationary service at medium or long time; however the result of the risk analysis prevents its development by using experimental prototypes. © 2012 by ESG.

Antonio Rivera Marquez J.,BUAP | Moises Bautista Rodriguez C.,Grupo Mexico | Herrera C.M.,BUAP | Rosas E.R.,Centro Universitario Of Vinculacion | And 2 more authors.
International Journal of Electrochemical Science | Year: 2011

Photocatalysis of organic compounds by mean to semiconductors depends heavily on its structural and superficial properties. For this reason, the aim of this paper is to investigate the effect of the ratio Zn/O, grain size and grain number of zinc oxide (ZnO) on photocatalysis of methylene blue dye (MB). ZnO deposits were obtained by cathodic electrodeposition technique from an experimental design 23. The three growth variables were voltage, temperature and time of deposition with two different levels for each variable. Our results showed that the crystallographic orientation and morphology of ZnO electrodeposited depend on different combinations of the deposit variables according to the experimental design. We also found that there is an optimum value in the ratio Zn/O, grain size and grain number of ZnO related to the higher degradation of MB. © 2011 by ESG.

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