Abstract: The present invention relates to an arylphenoxy catalyst system producing an ethylene homopolymer or copolymers of ethylene and ?-olefins, and a method of producing an ethylene homopolymer or copolymers of ethylene and ?-olefins having a high molecular weight under a high temperature solution polymerization condition using the same. The catalyst system includes a group IV arylphenoxy-based transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst. In the transition metal catalyst, a cyclopentadiene derivative and arylphenoxide as fixed ligands are located around the group IV transition metal, arylphenoxide is substituted with at least one aryl derivative and is located at the ortho position thereof, and the ligands are not crosslinked to each other. The catalyst includes an environmentally-friendly raw material, synthesis of the catalyst is economical, and thermal stability of the catalyst is excellent.

Abstract: A small cylindrical reformer according to the embodiments of the present invention are suitable for use in the production of hydrogen from fossil fuels for a small fuel cell power plant. In the small cylindrical reformer, a reforming reactor, a water gas shift reactor (high temperature or low temperature), a combustor, a heat exchanger, a steam generator, etc., may be integrated in a single container to form an optimal heat exchanging network, minimize heat loss and optimize heat exchange efficiency. Thereby, the reformer is designed to be easily processed and manufactured and to have a compact size, thus realizing high efficiency, light weight and ease of mass production.

Abstract: Disclosed is a vacuum cleaner including a sucking nozzle for sucking air; a dust collecting assembly including a dust collecting container with an opened top surface, a top lid for opening and closing a top of the dust collecting container, an inlet for sucking air to the inside of the dust collecting container, a filtering device coupled with the top lid, and an outlet provided at a bottom of the dust collecting assembly for discharging clean air to a lower part of the dust collecting container; and a cleaner body including a dust collecting assembly receiving recess for detachably receiving the dust collecting assembly, a polluted air outlet provided at the dust collecting assembly receiving recess and coupled with the dust collecting assembly inlet for discharging polluted air sucked in through the sucking nozzle, and a clean air inlet provided on a floor of the dust collecting assembly receiving recess and communicating with the outlet of the dust collecting assembly, and a clean air conduit for dischargi