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Copyright of Revista Ciencia y Poder Aéreo is the property of Escuela de Postgrados de la Fuerza Aerea Colombiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The increase in global temperature, as a result of greenhouse gas emissions, continues to be a major concern that has led to a deep interest in the implementation of hydrogen as a source of electric power generation; therefore, hydrogen fuel cell technologies have been developed and are available on the market to mitigate CO2 emissions generated by the use of fossil fuels. This document describes the methodology used for the design of an electric propulsion system with energy supply from a hydrogen fuel cell in a Light Cabotage and Logistic Support Vessel - BALC-L. The current design of the vessel has a conventional propulsion with two diesel engines of 224 bkW each and two diesel generators 99 ekW each, as the basis for the proposed analysis of an electric propulsion system energized through a hydrogen fuel cell system. As a result, a change in the operational profile of the vessel and a reduction in the CO2 emissions that it would generate throughout its useful life cycle are identified. The research described in this document is a starting point for the implementation of these technologies in the maritime and fluvial industry in Colombia. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Sociedad Química del Perú is the property of Sociedad Quimica del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article has main objective to project the cost of a fleet of 20 fuel cell buses for 2025 in the Valle del Aburrá (Colombia). As methodology it is begins of a previous study which projected the cost of hydrogen and where was analyzed the world situation in the production and use of hydrogen in fuel cells to adapt to the conditions of the Valle del Aburrá. The technical conditions are determined for the operation of a fleet of 20 fuel cell buses and an economic model was developed to determine the cost of implementation, of system operation, the cost per kilometer and cost per passenger. The main conclusions are that under the assumptions made and 2013 pesos, the costs per passenger for a transport company can vary from 478 $/passenger to 773 $/passenger, giving an economic feasibility to the implementation of a system of this type, without considering the profit environmental, health, quality of life and energy security by diversifying of the same. [ABSTRACT FROM AUTHOR]

Four ceramics type fluorite were obtained based on Ce1-XSmXO2-δ (x = 0, 5, 10 and 15 mol%), by progress of a wet chemical synthesis route with purpose of create in the material different physicochemical properties of importance for its potential application as electrode components in solid oxide fuel cells (SOFC). The characterization was performed at different stages of synthesis process, initially metalorganic precursors were characterized by infrared spectroscopy (FTIR) and thermal analysis (TGA-DTA), thereby determining the formation of citrate type species. Subsequent analysis after obtention of crystalline phases sought by X- ray diffraction (XRD) and scanning electron microscopy (SEM, TEM), allowed to evaluate morphology, and some surface and textural characteristics consistent with a set of nanosized aggregates ( < 41 nm), regularly oriented in the (111) plane, with interplanar distances of 0.31 nm. The composition was determined by microanalysis of energy dispersive X-ray (EDS) and X-ray fluorescence (XRF) indicating an excellent match between proposed and obtained compositions. Analysis of temperature-programmed reduction (TPR-H2) and AC impedance spectroscopy, confirmed the presence of relevant properties for use of these ceramics in SOFC systems. [ABSTRACT FROM AUTHOR]

In this paper different kinds of Solid Oxide Fuel Cells (SOFC) and their operating principles are presented. In terms of internal structure, SOFC can be classified into three categories: dual-chamber, single-chamber and no-chamber cells. Electrochemical performance is compared based on information available in the literature and advantages and disadvantages are established. Typical values of maximum power density (Pmax) and current density at Pmax are respectively: ∼ 1000 mW/cm²and ∼ 2000 mA/cm² for dual-chamber cells, ∼ 336 mW/cm² and ∼ 770 mA/cm² for singlechamber cells, and ∼ 210 mW/cm² and ∼ 440 mA/cm² for no-chamber cells. Although the electrochemical performance of the single- and no-chamber cells is lower than the dual-chamber cells, the operating advantages given are enough to consider them as viable alternative designs. Finally, are presented preliminary results of a new design of a no-chamber cell with a burner of porous media coupled with the fuel cell. [ABSTRACT FROM AUTHOR]

Through a study of a hydrogen fuel cell is able to compare its performance with the Nafion 117 membrane and without it, under different conditions of operation these conditions made it possible to analyze the progress of the reaction with the time of the degree of Conversion, the electrical performance, productivity, and the specific energy consumption. The figures of merit that is obtained from these comparisons are used to evaluate the function of the hydrogen fuel cell. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The forecast zenith of oil, the environmental regulations and the price of oil have encouraged the search for new efficient and not-so-polluting energy-producing devices. Undoubtedly, fuel batteries are devices that comply with these characteristics since they are more efficient than most combustion machines and generate fewer emissions. Thanks to these advantages, the fuel batteries market has been widening its scope. This article reviews the potential market for these batteries and the challenges faced by their inventors in order to position them in the market. The article it also mentions some of the commercially available products and international activities related to their development. [ABSTRACT FROM AUTHOR]

The development and working performance of a proton exchange membrane fuel cell stack (PEMFCS) which was installed at Base Esperanza belonging to the Argentinean Army in the Antarctic territory is presented. The set designed and installed allows working with minimum peripherical devices and can be operated and maintained by personnel with basic training. The ohmic resistance of the battery is the same that could be obtained from six elements in series; the Tafel slope is 80 mV/dec. Stability experiments were performed during 2278 hours, and the energy generated was 4.2 kWh. [ABSTRACT FROM AUTHOR]

Hydrogen, because of its large combustion heat, 572 kJ/mol, three times that of gasolines, and an environmentally compatible byproduct, water, is being considered as an alternative to fossil fuels derivatives; particularly in vehicular applications. The application of hydrogen as combustible in mobile technologies involves three challenges: the production from the water splitting, for instance; the availability of a reversible, safe and economically viable storage method; and its use through appropriate fuel cells where the chemical energy is directly transformed in electricity. Nature practically has no free H2. From this fact, H2 must be produced. It is a secondary energy bearer, not a primary source like petroleum. The storage is probably the main of these challenges because H2 has very low critical temperature (Tc = 32.97 K) and at ordinary temperatures it is supercritical gas. The H2 liquefaction is possible when the strength for the H2-H2 interactions (of van der Waals and quadrupole-quadrupole type) surpasses the thermal energy (kT). This suggests the possibility of be able the H2 storage at temperatures above Tc through a strong H2-surface interaction in solids of extended surface, layered or nanoporous materials, for instance. In this contribution the possible H2 - surface interactions that could be present in such storage method and their relative contributions to the H2 adsorption energy in materials of extended surface are discussed. The role of these interactions is discussed from experimental results on H2 in nanocavities. The state of art and perspectives on this storage method are also evaluated. [ABSTRACT FROM AUTHOR]

The mathematical modeling and the simulation of a hydrogen purification system is carried out in the present work. The hydrogen is produced in a bioethanol steam reforming reactor. The proposed plant has two catalytic reactors where the carbon monoxide content is reduced below 20 ppm, allowing in that way the coupling of the system with a polymeric fuel cell. The kinetic model used in the design and simulation has shown good results. It is demonstrated that the WGSR can be carried out at 3 atm and 523K in an adiabatic reactor, while the PROX reactor should be operated isothermally at 433K-453K avoiding the catalyst sintering and considering the system safety. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previously that had seted out that NH4H2PO4 (ADP) shows to thermal changes in T1 = 430 K and 483 T2 = K accompanied with loss of weight that can be associate to reactions of superficial dehydration of the type of the suggested by Lee. Our measures corroborate the existence of these thermal changes near the values of T1 and T2. When watching the evolution of the balance of phases in the Lix(NH4)(1-x)H2PO4 system (LADP), we observed a landslide of the observed transitions. When warming up the fresh samples, the network of phosphates is almost identical in the LiH2PO4 and the NH4H2PO4 since the ions (H2PO4) - they are united respectively by ionic connections to the ions Li+ and NH4+ due to the lost of the constitutional water that they have. The measures of thermogravimetry verify the theory predicted by Lee on the condensation of dihydrogenated phosphates, being observed the formation of new compounds for each value of x. When replacing ion NH4+ by the Li+ ion in the LADP, obtains a less heavy system with very good conductivities and less tendency to lose the structural H2O that it has and that favors to the conductivity of the system being this very useful result in the application of fuel cells. [ABSTRACT FROM AUTHOR]

The article presents a study that focuses on the solution to the actual energy problems and to the progressive damage of the environment across the globe. In this study, it is carried out an analysis of the various types of fuel cells and the current state of the decentralized energy production, which allows the energy transformation with technologies preferably not pollutants in the place of consumption.

It was possible to study the performance of a Phosphoric Acid Fuel Cell with the "In Situ" Electrochemical Impedance Spectroscopy Technique. The technique has a great potential as a effective tool to carry out studies in the fuel cell field. [ABSTRACT FROM AUTHOR]

In this work the design of a polymer electrolyte membrane fuel cell (PEMFC) fed with oxygen from air and a mix of hydrogen and carbon monoxide is presented. With this aim, the use of nanostructured core/shell type electrocatalysts supported in carbon Vulcan XC-72R is proposed, where the core is a noble metal (Au) while the shell is Pt. [ABSTRACT FROM AUTHOR]

In the present work we are reporting the results of an implementation to an automatic set-up to characterize fuel cells that are using a proton exchange membrane (PEM). A virtual interface is developed by means of graphical programmin using the last generation G language (LabView) for virtual instrumentation. This approach allows the user to control laboratory instruments that might contain an interface of communication with the computer ports, such as those that automatize the processes of the fuel cell in which the set-up was tested sucessfully. [ABSTRACT FROM AUTHOR]

Se considera una investigación de la viabilidad técnico-económica de la generación energética a partir de hidrógeno. Se describe la tecnología de celdas de combustible, se comenta sobre los aspectos teóricos que comprende y se reflexiona sobre la factibilidad de su introducción como fuente alternativa de energía en Cuba.