Abstract:
Method of making a membrane electrode assembly comprising: providing a membrane comprising a perfluorinated sulfonic acid; providing a first transfer substrate; applying to a surface of the first transfer substrate a first ink, said first ink comprising an ionomer and a catalyst; applying to the first ink a suitable non-aqueous swelling agent; forming an assembly comprising: the membrane; and the first transfer substrate, wherein the surface of the first transfer substrate comprising the first ink and the non-aqueous swelling agent is disposed upon one surface of the membrane; and heating the assembly at a temperature of 150° C. or less and at a pressure of from about 250 kPa to about 3000 kPa or less for a time suitable to allow substantially complete transfer of the first ink and the second ink to the membrane; and cooling the assembly to room temperature and removing the first transfer substrate and the second transfer substrate.
Abstract:
A sulfonated poly(arylene ether) copolymer that has a crosslinking structure in a chain of a polymer, a sulfonated poly(arylene ether) copolymer that has a crosslinking structure in and at an end of a chain of a polymer, and a polymer electrolyte film that is formed by using them are disclosed. According to the polycondensation reaction of the sulfonated dihydroxy monomer (HO—SAr1-OH), the none sulfonated dihydroxy monomer (HO—Ar—OH), the crosslinkable dihalide monomer (X—CM-X) and the none sulfonated dihalide monomer (X—Ar—X), the poly(arylene ether) copolymer in which the sulfonic acid is included is synthesized. The formed poly(arylene ether) copolymer has the crosslinkable structure in the chain of the polymer. In addition, by carrying out the polycondensation reaction in respects to the crosslinkable monohydroxy monomer or the crosslinkable monohalide monomer, the crosslinking can be formed at the end of the polymer. Through this, the thermal stability, the mechanical stability, the chemical stability, the film formation ability and the like is the same as or better than those of the Nafion film that is currently commercialized and is used as the polymer electrolyte film, and the proton conductivity and the cell performance are excessively improved. In addition, even though it is exposed to the moisture over a long period of time, since there is no change in the property of the electrolyte film, the dimensional stability is high.
Abstract:
A method for allocating slots for a synchronous Ethernet service in a Residential Ethernet system includes the steps of: receiving requests for synchronous Ethernet services from terminals requiring the synchronous Ethernet services; calculating a number of slots for each synchronous Ethernet service, and allocating slots for each terminal based on the calculated number of slots; transmitting information about the allocated slots through at least one Residential Ethernet switch; and receiving acknowledgement signals from the terminals in response to the allocated slot information and providing the synchronous Ethernet services using the allocated slots.
Abstract:
A Base Transceiver Station (BTS) for interworking a Wireless Local Area Network (W-LAN) and a mobile communication network through a Radio-over-Fiber (RoF) link is provided. The BTS having mobile and fixed wireless service distribution functions includes a Wireless Local Area Network Access Point (W-LAN AP), a wireless service function block, a Radio Frequency (RF) converter, and an optical transmitter. The wireless service function block performs transmission/reception to/from a predetermined mobile terminal via a connection for the voice call communication and data communication with an external Base Station Controller (BSC). The RF converter performs a data communication connection with the external BSC, up-converts data from the BSC into W-LAN frequency band data, and down-converts data to the BSC into baseband data. The optical transmitter transmits the up-converted data of the packet data RF converter to the W-LAN AP through a RoF link.