Abstract: This invention provides a p-type group III nitride semiconductor, with good p-type properties, having a composition expressed by AlXGaYInZN in which each of X, Y and Z indicates a rational number satisfying a relationship of X+Y+Z=1.0, even if Al content is as high as 1.0>X?0.5. It is achieved that a proportion of a hole concentration at 30° C. to an acceptor impurity atom concentration is 0.001 or more in the p-type group III nitride semiconductor of the invention, by doping acceptor impurity atoms such as Mg in concentration of 5×1018 to 1×1020 cm?3 using the method, for example, MOCVD with attention not to incorporate an impurity atom other than the acceptor impurity atom or not to form dislocation in the crystal when producing the group III nitride semiconductor expressed by the above composition.

Abstract: A power generation system includes an alkaline fuel cell provided with an electrolyte membrane which is an anion exchange membrane and a pair of electrodes (an anode and a cathode) arranged on the both sides of the electrolyte membrane. The alkaline fuel cell can generate an electric power by supplying a fuel gas and an oxidizing agent gas to the anode side and the cathode side, respectively. The power generation system uses a hydrogen gas containing a basic compound such as ammonia as the fuel gas to be supplied to the anode side.

Abstract: Disclosed is a process for producing a diaphragm for a fuel cell comprising a modified anion exchange membrane that substantially maintains durability and hydroxide ion conductivity as an electrolyte membrane and has improved resistance to methanol permeation. The process is characterized by comprising the step of impregnating at least one side of a crosslinked hydrocarbon anion exchange membrane with a polymerizable acidic compound having a weight average molecular weight of not less than 700 and less than 8000, provided that, when the acid site in the compound has been neutralized with a counter cation, the weight of the counter cation is subtracted from the molecular weight, and polymerizing the polymerizable acidic compound.

Abstract: This invention provides a self supporting substrate which consists of a n-type conductive aluminum nitride semiconductor crystal and is useful for manufacturing the vertical conductive type AlN semiconductor device. The n-type conductive aluminum nitride semiconductor crystal, by which the self supporting substrate is made up, contains Si atom at a concentration of 1×1018 to 5×1020 cm?3 is substantially free of halogen atoms and substantially does not absorb the light having the energy of not more than 5.9 eV. The self supporting substrate can be obtained by a method comprising the steps of forming an AlN crystal layer on a single crystal substrate such as a sapphire by the HVPE method, preheating the obtained substrate having the AlN crystal layer to a temperature of 1,200° C. or more, forming a second layer consisting of the n-type conductive aluminum nitride semiconductor crystal is formed on the AlN crystal layer in high rate by the HVPE method and separating the second layer from the obtained laminate.

Abstract: Disclosed is an anion-exchange membrane which does not easily deteriorate even when used at high temperatures in a strong alkaline atmosphere. Also disclosed is a method for producing the anion-exchange membrane. The anion-exchange membrane is a microporous membrane which is composed of a water-insoluble resin and an anion-exchange resin filling the pores of the microporous membrane. The anion-exchange resin is composed of an anion-exchange resin wherein a quaternary ammonium salt group serving as an anion-exchange group is directly bonded to an aliphatic hydrocarbon chain, said anion-exchange resin being obtained by polymerizing and crosslinking a monomer composition which contains a crosslinking agent and a monomer component including a diallyl ammonium salt.

Abstract: Disclosed is a membrane for a fuel cell, which comprises: a polymer electrolyte membrane which comprises a cross-linked anion-exchange resin having a strongly basic anion-exchange group such as a quaternary ammonium salt group, a quaternary pyridinium salt group and a quaternary imidazolium salt group; and a polymer which is attached on at least one surface of the polymer electrolyte membrane and has a weakly acidic group such as a polyacrylic acid. Also disclosed is a method for producing the membrane.

Abstract: A metal fluoride single crystal pulling apparatus that upward pulling initiation through termination, in the state of shallow melt capable of highly effective inhibition of scatterer formation, can perform stable growth of single crystal and can suppress any mixing of air bubbles and occurrence of crystal break during crystal growth, etc; and a process for producing a metal fluoride single crystal therewith. As a crucible for accommodating a melt of raw metal fluoride, use is made of a double structured crucible composed of an outer crucible and an inner crucible. In the upward pulling of single crystal, the accommodation depth of inner crucible relative to the outer crucible is increased in accordance with any decrease of melt accommodated in the inner crucible according to the growth of single crystal, so that the melt accommodated in the outer crucible is fed into the inner crucible to thereby maintain the amount of melt accommodated in the inner crucible within a given range.

Abstract: An anion-exchange membrane having quaternary ammonium groups or quaternary phosphonium groups wherein halogen ions serve as the counter ions is obtained. Rather than being subjected to ion exchange with an OH-type membrane using a toxic substance such as sodium hydroxide, the halogen-type anion exchange membrane is brought into contact with a carbonate solution and/or bicarbonate solution to directly obtain an anion exchange membrane where at least some of the counterions of the quaternary ammonium groups or quaternary phosphonium groups are CO32? and/or HCO3?.

Abstract: A stable, high output is obtained with an anion exchange membrane-type fuel cell that generates electricity when air is supplied. An operating method for an anion exchange membrane-type fuel cell includes an anion exchange membrane electrode assembly for which an anode is joined to one surface of a anion exchange membrane and a cathode is joined to the other surface, and air is supplied to the cathode, wherein air with a reduced carbon dioxide concentration in the atmosphere is supplied to the cathode by a low carbon dioxide air supply system that supplies air with the reduced carbon dioxide concentration to the cathode.

Abstract: This invention provides a p-type group III nitride semiconductor, with good p-type properties, having a composition expressed by AlxGayInzN in which each of X, Y and Z indicates a rational number satisfying a relationship of X+Y+Z=1.0, even if Al content is as high as 1.0>X?0.5. It is achieved that a proportion of a hole concentration at 30° C. to an acceptor impurity atom concentration is 0.001 or more in the p-type group III nitride semiconductor of the invention, by doping acceptor impurity atoms such as Mg in concentration of 5×1018 to 1×1020 cm?3 using the method, for example, MOCVD with attention not to incorporate an impurity atom other than the acceptor impurity atom or not to form dislocation in the crystal when producing the group III nitride semiconductor expressed by the above composition.

Abstract: A method of producing a group III nitride such as aluminum nitride, comprising the step of reacting a group III halide gas such as aluminum trichloride gas with a nitrogen source gas such as ammonia gas in a growth chamber to grow a group III nitride on a substrate held in the growth chamber, wherein the method further comprises premixing together the group III halide gas and the nitrogen source gas to obtain a mixed gas and then introducing the mixed gas into the growth chamber without forming a deposit in the mixed gas substantially to be reacted each other. For the growth of a group III nitride such as an aluminum-based group III nitride by HVPE, there are provided a method of producing the group III nitride having as high quality as that obtained by the method of the prior art at a high yield and an apparatus used in the method.

Abstract: Disclosed is a method for producing an ion-conductivity providing agent for a catalyst electrode layer of an anion-exchange membrane type fuel cell comprising: producing anionic conductive resin including a quaternary onium base having a halogeno ion as its counterion, and bringing the halogen type anionic conductive resin into contact with carbonate solution and/or bicarbonate solution to directly obtain anionic conductive resin in which at least a part of the counterion of said quaternary onium base is CO32? and/or HCO3?, without ion exchange of the counterion to OH-type by using deleterious substance such as sodium hydroxide. The purpose is to provide a method for stably producing an ion-conductivity providing agent used for giving ion conductivity to a catalyst electrode layer of an anion-exchange membrane type fuel cell, the method being easy to operate, the ion-conductivity providing agent showing constant effect for giving ion conductivity.

Abstract: This invention provides a selfsupporting substrate which consists of a n-type conductive aluminum nitride semiconductor crystal and is useful for manufacturing the vertical conductive type AlN semiconductor device. The n-type conductive aluminum nitride semiconductor crystal, by which the selfsupporting substrate is made up, contains Si atom at a concentration of 1×1018 to 5×1020 cm?3, is substantially free from halogen atoms, and substantially does not absorb the light having the energy of not more than 5.9 eV. The selfsupporting substrate can be obtained by a method comprising the steps of forming an AlN crystal layer on a single crystal substrate such as a sapphire by the HVPE method, preheating the obtained substrate having the AlN crystal layer to a temperature of 1,200° C. or more, forming a second layer consisting of the n-type conductive aluminum nitride semiconductor crystal is formed on the AlN crystal layer in high rate by the HVPE method and separating the second layer from the obtained laminate.

Abstract: Disclosed is a membrane for polymer electrolyte fuel cells, which is composed of a hydrocarbon anion-ex-change resin membrane wherein an anion-exchange group is covalently bonded to a hydrocarbon resin, and an adhesive layer formed on at least one side of the hydrocarbon anion-exchange resin membrane. The membrane for polymer electrolyte fuel cells is characterized in that the adhesive layer is made of an anion-exchange resin having a Young's modulus of 1-1000 MPa.

Abstract: Disclosed is a separation membrane for direct liquid fuel cells, which is composed of a quaternary ammonium-type anion exchange membrane. The quaternary ammonium-type anion exchange membrane is produced as follows: a polymerizable composition containing a styrene having a haloalkyl group, a crosslinking polymerizable monomer, a compound having an epoxy group and an effective amount of a polymerization initiator is brought into contact with a porous film, so that the pores of the porous film are filled with the polymerizable composition that is then polymerized therein; then a quaternary ammonium group is introduced into the bromoalkyl group; and then the counter ion of the quaternary ammonium group is ion-exchanged into a hydroxide ion. Also disclosed is a method for producing the quaternary ammonium-type anion exchange membrane.

Abstract: Disclosed is a solid polymer electrolyte fuel cell membrane comprising an anion exchange membrane that contains a hydrocarbon-based anion exchange resin, wherein the water permeability at 25° C. is 1400 g m?2 hr?1 or greater, the anion exchange capacity is 0.2 to 5.0 mmol·g?1, the percentage of water content at 25° C. is 7% by weight or greater, and the thickness is 3 to 50 ?m. It is especially preferable as a solid polymer electrolyte fuel cell membrane when said anion exchange membrane is an ion exchange membrane with a 5 to 15?m-thick porous membrane substrate, wherein the voids in said porous membrane are filled with a hydrocarbon-based anion exchange resin.

Abstract: The present invention can provide an anion exchange type separation membrane used for direct liquid fuel type fuel cell, high in heat resistance, hard to deteriorate when using and capable of obtaining high battery output. A composite membrane used as the separation membrane for fuel cell can be obtained by using a porous film, composed of a hydrolysis resistant polyimide resin such as a polyimide resin having a fluorenylidene group in a main framework, as a substrate; optionally increasing water retention characteristics for example by applying a water-retentive resin to at least a part of a surface of the porous film; and then filling an anion-exchange resin such as a cross-linked hydrocarbon-based anion-exchange resin having a quaternary ammonium group as an anion exchange group into a void portion of the porous film.

Abstract: There is provided a method capable of obtaining an aluminum-based group III nitride crystal layer having a smooth surface and high crystallinity by employing only HVPE in which inexpensive raw materials can be used to reduce production costs and high-speed film formation is possible without employing MOVPE. To produce a group III nitride crystal by HVPE comprising the step of growing a group III nitride crystal layer by vapor-phase growth on a single crystal substrate by contacting the heated single crystal substrate with a raw material gas containing a group III halide and a compound having a nitrogen atom, the group III nitride crystal is grown by vapor-phase growth on the single crystal substrate heated at a temperature of 1,000° C. or more and less than 1,200° C. to form an intermediate layer and then, a group III nitride crystal is further grown by vapor-phase growth on the intermediate layer on the substrate heated at a temperature of 1,200° C. or higher.

Abstract: A method of producing a group III nitride such as aluminum nitride, comprising the step of reacting a group III halide gas such as aluminum trichloride gas with a nitrogen source gas such as ammonia gas in a growth chamber to grow a group III nitride on a substrate held in the growth chamber, wherein the method further comprises premixing together the group III halide gas and the nitrogen source gas to obtain a mixed gas and then introducing the mixed gas into the growth chamber without forming a deposit in the mixed gas substantially to be reacted each other. For the growth of a group III nitride such as an aluminum-based group III nitride by HVPE, there are provided a method of producing the group III nitride having as high quality as that obtained by the method of the prior art at a high yield and an apparatus used in the method.

Abstract: A particulate porous ammoxidation catalyst for use in producing acrylonitrile or methacrylonitrile by reacting propylene, isobutene or tert-butyl alcohol with molecular oxygen and ammonia in a fluidized-bed reactor, the catalyst comprising a metal oxide and a silica carrier having supported thereon the metal oxide, wherein the metal oxide contains at least two elements selected from the group consisting of molybdenum, bismuth, iron, vanadium, antimony, tellurium and niobium, and the catalyst having a particle diameter distribution wherein the amount of catalyst particles having a particle diameter of from 5 to 200 ?m is from 90 to 100% by weight, based on the weight of the catalyst, and having a pore distribution wherein the cumulative pore volume of pores having a pore diameter of 80 ? or less is not more than 20%, based on the total pore volume of the catalyst and wherein the cumulative pore volume of pores having a pore diameter of 1,000 ? or more is not more than 20%, based on the total pore volume of the