An iron-phthalocyanine complex was utilized as a cathode for constructing a one-compartment hydrogen peroxide fuel cell operated under acidic conditions for the first time. The protonation to the phthalocyanine ligand is crucial to exhibit high activity toward hydrogen peroxide reduction. NafionÒ coating of the anode improved the stability of the fuel cell.A new energy carrier instead of fossil fuels should be developed to realize a sustainable development. [1][2][3][4] Hydrogen peroxide (H 2 O 2 ) is a potential candidate as a new energy carrier, because it can be produced by the two-electron reduction of oxygen, which is abundant in air, and also by the two-electron oxidation of water that is more abundant on the earth. [5][6][7] In addition, H 2 O 2 has high energy density with none of the environmental problems caused by most other fuels, because H 2 O 2 decomposes to water and oxygen. [5][6][7] In order to use H 2 O 2 as a green energy carrier, two technological issues should be addressed: one is production of H 2 O 2 by utilizing natural energies such as solar, wind, etc.; the other is production of electricity using H 2 O 2 fuel cells. [7][8][9] We have reported that H 2 O 2 can be produced by using electrical power of a photovoltaic solar cell in the presence of Co porphyrins as catalysts under acidic conditions, when the current efficiency reached nearly 100%. 7 H 2 O 2 thus produced can be used in

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This paper proposes a Multi-hop Radio Access Cellular (MRAC) scheme for achieving both highspeedihigh-capacity and good area coverage in fourth generation mobile communications systems. In this scheme, we assume two kinds of hop stations, one is a dedicated repeater station installed at a good propagation location such as a rooftop, and the other is a user terminal that temporarily experiences good propagation conditions. For both cases, the path diversity effect can be obtained between single-hop and multi-hop paths. Four propagation models were studied representing the paths among the base station, hop stations, and mobile station. Based on the propagation models, suitable MRAC operation conditions are discussed. For mobile stations located at the cell edge area, MRAC operation is effective in reducing the transmit power. Consequently, MRAC reduces the interference in cellular systems and enhances the area coverage.