Abstract:
A redox flow battery has a high energy density and an excellent charge and discharge efficiency because re-precipitation is prevented in an electrolyte solution or eduction is prevented in an electrode during reduction of a metal ion used as an electrolyte.
Abstract:
A solid proton conductor for a fuel cell and a fuel cell employing the solid proton conductor, the solid proton conductor including a sulfonated polymer, and a hydrophilic polymer having an acid group, constituting a polymer solvent, providing a proton mobile path.
Abstract:
A polysulfone is provided with a nitrogen-containing functional group having an affinity to an acid, an electrolyte membrane using the polysulfone, and a fuel cell including the electrolyte membrane. In particular, the polysulfone includes a nitrogen-containing functional group that has an affinity to an acid, such as a phosphoric acid, thereby having an excellent acid retaining ability. In an electrolyte membrane including the polysulfone and an acid, the amount of the retained acid can be controlled. Therefore, the electrolyte membrane has a high ionic conductivity and a high mechanical strength. A polysulfone blend of polysulfone and a thermoplastic resin prevents the dissolution of polysulfone by phosphoric acid, so that an electrolyte membrane using the polysulfone blend has an improved durability. A cross-linked reaction product of polysulfone, a cross-linking agent and a polymerization product of polysulfone, a thermoplastic resin, and a cross-linking agent strongly resist a phosphoric acid. Thus, a fuel cell using these polymerization products has a long lifetime and can operate at a high temperature and at a high efficiency.
Abstract:
A rail-to-rail class AB amplifier includes an input circuit for converting a voltage difference between a first input signal and a second input signal into respective currents, a first current adder circuit for adding a drain current of a first input NMOS transistor and a drain current of a second input NMOS transistor, a second current adder circuit for adding a drain current of a first input PMOS transistor and a drain current of a second input PMOS transistor, a floating current source for controlling a bias current of the first current adder circuit and the second current adder circuit, a control circuit for controlling a voltage level of the drain terminal of a second cascode PMOS transistor and a second cascode NMOS transistor, and an output circuit coupled to the drain terminals of the second cascode PMOS transistor and the second NMOS transistor.
Abstract:
Disclosed herein are novel microorganisms having excellent biodegradability and a method for the bioremediation of oil-contaminated soil. The novel microorganisms are specified as Rhodococcus baikoneurensis EN3 KCTC19082, Acinetobacter johnsonii EN67 KCTC12360 and Acinetobacter haemolyticus EN96 KCTC12361. In the bioremediation method, in addition to said novel microorganisms, various microorganisms of Nocardia sp., Gordonia sp., Rhodococcus sp. and Acinetobactor sp. can be used, and the oil biodegradation activities of these microbial strains can be increased by adding biosurfactant 2-alkyl-3-hydroxylic acid or its derivative. According to the disclosed invention, oil-contaminated soils can be purified in an effective, economical and eco-friendly manner compared to prior bioremediation methods.
Abstract:
A polymer electrolyte membrane for use in a fuel cell and a method of producing a polymer electrolyte membrane. The method includes preparing a phosphate monomer solution by dissolving an initiator and a phosphate monomer containing at least one phosphoric acid group and at least one unsaturated bond in a solvent, impregnating a porous polymer matrix with the phosphate monomer solution, polymerizing the impregnated phosphate monomer, and impregnating the result of polymerization with a phosphoric acid.
Abstract:
The present invention relates to a polymer electrolyte membrane that includes a porous polymer matrix and an ion conducting polymer coating membrane formed in the outer surface of single fibers in the porous polymer matrix. The polymer electrolyte membrane can provide excellent mechanical strength, is not deteriorated by heat even at a temperature higher than 100°C., can provide excellent ion conductivity even at non-humidified state. Thus it is suitable for use in a fuel cell that is operated at high temperatures.
Abstract:
Disclosed herein is an image photographing device capable of being auto-focused while moving a lens barrel in an optical axis direction. The image photographing device includes: a lens barrel having at least one lens; a housing receiving the lens barrel therein so that the lens barrel moves in an optical axis direction; and an impact reducing unit elastically supporting the lens barrel in the case in which the lens barrel deviates from a set movement range, thereby primarily damping the lens barrel before the lens barrel deviates from the movement range to collide with other components positioned at an outer side of the lens barrel.