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Interactions of Nafion (Naf) ionomer with water, aqueous ethanol (EA), aqueous isopropyl alcohol (IPA), and aqueous ammonia were investigated by attenuated total reflectance (ATR)–infrared (IR) spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and computational modeling studies. Microstructural features by ATR–IR revealed the existence of hydrophilic interaction of Naf with all solvents. The Naf membranes formed hydrogen bonds with water, aqueous EA, and IPA. The incorporation of solvents on the Naf matrix impaired the crystallinity, which was highest in the case of IPA. Of all the microsolvated structures of Naf investigated, the formation of H3O+ ions was evident; in addition, H5O2+ ions appeared in the alcohol–water mixture, and NH4+ ions were observed in the water–ammonia mixture along with a direct ion pair with the SO3− group in Naf. Theoretical studies based on computational modeling disclosed that the interchain distance increased with enhanced interactions (hydrophobic interactions in particular), and this was in good agreement with the highest swelling ratio of the Naf membrane in aqueous IPA and EA solvents. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

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The paper presents the details of control strategy for power plant based on a 1kW proton exchange membrane fuel cell stack. The system consists of a Proton exchange membrane fuel cell stack, and ancillary devices like valves, coolant pumps, gas heaters and blowers which constitutes the balance of plant. The powering scheme considered for the balance of plant involves linear voltage regulators and dc-dc converters. Balance of plant (BOP) is responsible for keeping the electrode stack under proper conditions and enabling load delivery as per the demand. Regulation of gas flow in accordance with current drawn, control of gas humidification levels etc. form some of the key aspects in this regard. V-I characteristics of the Polymer Electrolyte Membrane Fuel Cell (PEMFC) stack, generated by operating the stack with a BOP based on the control strategy shows adequate performance.

Abstract-Solar radiation falling on earth is far more than energy demand of the world, but because of issues related to storage and economics, it is not possible to rely on it, when it comes to fulfill huge electricity demands at national level. A world super grid, connecting all the continents is reported, which is expected to avoid this need of energy storage, while powering the whole world throughout the day by transmitting excess electricity. Feasibility of such grid is determined by matching supply and demand of a particular region. World super grid will be powered by solar photovoltaic panels installed all over the world to facilitate the utilization of solar insolation. At any point of time, Sun shining area will supply electricity to that area itself along with other parts, which are in dark. Electricity demands of regions are analyzed and switching between supplying and demanding regions is modelled according to motion of the sun throughout the day. Several positive impacts of the grid such as environmental, economic and international relations are evaluated. Country preference for such grid is another key issue. Grid preference index is proposed in order to classify countries according to their preference for this grid, considering various factors such as its land area, geographical position and energy security. Policies at national and international level are recommended for smooth implementation of the grid. Elements of this analysis, which can be investigated further to make this rudimentary model more sophisticated are discussed.