Abstract: A desalination method includes: introducing a liquid to a reservoir layer to place the liquid above a water-repellent particle layer; heating and evaporating the liquid placed above the water-repellent particle layer to generate water vapor and deposit impurities on the sheet; liquefying the water vapor by a liquefying layer to obtain fresh water; and removing the sheet on which the impurities have been deposited from a desalination apparatus.

Abstract: A desalination apparatus that includes: a water-repellent particle layer that is located below a water tank, contains water-repellent particles, and allows passage of water vapor generated by evaporation of the liquid stored in the water tank, the water tank being a space for storing the liquid; and a liquefying layer that is located below the water-repellent particle layer, and liquefies the water vapor that has passed through the water-repellent particle layer to obtain the fresh water. The water-repellent particle layer includes: a first layer that contains first water-repellent particles among the water-repellent particles, and faces the water tank; and a second layer that contains second water-repellent particles among the water-repellent particles, and is provided below the first layer. The second water-repellent particles have a larger average particle size than the first water-repellent particles.

Abstract: The desalination apparatus according to the present disclosure includes: a water-repellent particle layer that is located below a water tank, contains water-repellent particles, and allows passage of water vapor generated by evaporation of the liquid stored in the water tank, the water tank being a space for storing the liquid; and a liquefying layer that is located below the water-repellent particle layer, and liquefies the water vapor that has passed through the water-repellent particle layer to obtain the fresh water. The water-repellent particle layer includes an anti-migration layer provided as a surface layer that faces the water tank and containing anti-migration particles. Each of the anti-migration particles has a higher aspect ratio than the water-repellent particles, the aspect ratio being a value obtained by dividing a length in a major axis direction by a length in a minor axis direction.

Abstract: A water amount controlling method according to the present disclosure includes: opening a discharge valve that discharges a liquid from a water tank if an impurity concentration is higher than or equal to a first reference value, and opening a sluice gate that introduces the liquid to the water tank a predetermined period after opening the discharge valve, the first reference value being lower than a saturation concentration; throttling the discharge valve and the sluice gate if the impurity concentration is higher than or equal to a second reference value and the temperature is lower than or equal to a third reference value, the second reference value being lower than the first reference value; and closing the discharge valve if the impurity concentration is lower than the second reference value, and closing the sluice gate a predetermined period after closing the discharge valve.

Abstract: A desalination system, etc. of the present disclosure includes: a water tank; a water-repellent particle layer that is located below the water tank and contains a plurality of water-repellent particles; a liquefying layer that is located below the water-repellent particle layer and liquefies water vapor that has passed through the water-repellent particle layer, to obtain fresh water; an introduction channel of a liquid supply channel that supplies a liquid to the water tank; and a liquid speed reduction part that is located on the introduction channel of the supply channel, and includes a wall surface crossing a flow direction of the liquid in the supply channel, for reducing a flow speed of the liquid.

Abstract: A water repellent sand layer that is made of water repellent sand and serves as a water shield layer is provided to be slanted between upper and lower soil layers, a water conveying belt portion is provided to include at least one or both of gravel and a culvert that are provided between the water repellent sand layer and the upper soil layer, and a water shield wall is provided at a slant downstream side. Water falling and permeating from a ground surface into the soil layer is blocked by the water repellent sand layer, flows downward in the water conveying belt portion located above the water repellent sand layer to the slant downstream side, and is blocked by the water shield wall at the slant downstream side, so that the collected water is recovered from a drain hole in the culvert that penetrates the water shield wall.

Abstract: A water storage structure includes an impermeable layer including a plurality of hydrophobic particles, a water retentive layer provided on the impermeable layer and capable of holding a predetermined volume of liquid, and a pavement layer provided on the water retentive layer and including a tube penetrating from a first surface to a second surface.

Abstract: A water repellent sand mixture includes at least water repellent sand and cement at a weight ratio of 2% or more and 5% or less relative to the water repellent sand. The mixture achieves condensation between the water repellent sand particles by the hydration reaction of the cement, which improves dynamic stability. The mixture can be kept in a block shape due to such improved dynamic stability, water repellency, and less slidable surfaces of the sand particles.

Abstract: A desalination method disclosed herein includes: introducing a liquid to a reservoir layer to place the liquid above a water-repellent particle layer; heating and evaporating the liquid placed above the water-repellent particle layer to generate water vapor; liquefying the water vapor by a liquefying layer to obtain fresh water; determining whether or not impurities have been deposited on a sheet; and removing the sheet from a desalination apparatus if it is determined that the impurities have been deposited.

Abstract: A water repellent sand mixture includes at least water repellent sand and cement at a weight ratio of 2% or more and 5% or less relative to the water repellent sand. The mixture achieves condensation between the water repellent sand particles by the hydration reaction of the cement, which improves dynamic stability. The mixture can be kept in a block shape due to such improved dynamic stability, water repellency, and less slidable surfaces of the sand particles.

Abstract: A water amount controlling method according to the present disclosure includes: opening a discharge valve that discharges a liquid from a water tank if an impurity concentration is higher than or equal to a first reference value, and opening a sluice gate that introduces the liquid to the water tank a predetermined period after opening the discharge valve, the first reference value being lower than a saturation concentration; throttling the discharge valve and the sluice gate if the impurity concentration is higher than or equal to a second reference value and the temperature is lower than or equal to a third reference value, the second reference value being lower than the first reference value; and closing the discharge valve if the impurity concentration is lower than the second reference value, and closing the sluice gate a predetermined period after closing the discharge valve.

Abstract: A desalination apparatus according to one aspect of the present disclosure obtains fresh water from a liquid. The desalination apparatus includes: a water-repellent particle layer that is located below a water tank, contains water-repellent particles, and allows passage of water vapor generated by evaporation of the liquid stored in the water tank, the water tank being a space for storing the liquid; and a liquefying layer that is located below the water-repellent particle layer, and liquefies the water vapor that has passed through the water-repellent particle layer to obtain the fresh water. The water-repellent particle layer includes: a first layer that contains first water-repellent particles among the water-repellent particles, and faces the water tank; and a second layer that contains second water-repellent particles among the water-repellent particles, and is provided below the first layer.

Abstract: A desalination system, etc. of the present disclosure includes: a water tank; a water-repellent particle layer that is located below the water tank and contains a plurality of water-repellent particles; a liquefying layer that is located below the water-repellent particle layer and liquefies water vapor that has passed through the water-repellent particle layer, to obtain fresh water; an introduction channel of a liquid supply channel that supplies a liquid to the water tank; and a liquid speed reduction part that is located on the introduction channel of the supply channel, and includes a wall surface crossing a flow direction of the liquid in the supply channel, for reducing a flow speed of the liquid.

Abstract: The desalination apparatus according to the present disclosure includes: a water-repellent particle layer that is located below a water tank, contains water-repellent particles, and allows passage of water vapor generated by evaporation of the liquid stored in the water tank, the water tank being a space for storing the liquid; and a liquefying layer that is located below the water-repellent particle layer, and liquefies the water vapor that has passed through the water-repellent particle layer to obtain the fresh water. The water-repellent particle layer includes an anti-migration layer provided as a surface layer that faces the water tank and containing anti-migration particles. Each of the anti-migration particles has a higher aspect ratio than the water-repellent particles, the aspect ratio being a value obtained by dividing a length in a major axis direction by a length in a minor axis direction.

Abstract: A water repellent sand layer that is made of water repellent sand and serves as a water shield layer is provided to be slanted between upper and lower soil layers, a water conveying belt portion is provided to include at least one or both of gravel and a culvert that are provided between the water repellent sand layer and the upper soil layer, and a water shield wall is provided at a slant downstream side. Water falling and permeating from a ground surface into the soil layer is blocked by the water repellent sand layer, flows downward in the water conveying belt portion located above the water repellent sand layer to the slant downstream side, and is blocked by the water shield wall at the slant downstream side, so that the collected water is recovered from a drain hole in the culvert that penetrates the water shield wall.

Abstract: A water storage structure includes an impermeable layer including a plurality of hydrophobic particles, a water retentive layer provided on the impermeable layer and capable of holding a predetermined volume of liquid, and a pavement layer provided on the water retentive layer and including a tube penetrating from a first surface to a second surface.

Abstract: A polymer electrolyte fuel cell includes a cathode, an anode, and an electrolyte membrane sandwiched between the cathode and the anode. A plurality of projections each having a height of 5 to 15 ?m or a plurality of depressions each having a depth of 5 to 15 ?m are formed on a surface of the electrolyte membrane, the surface being opposed to the cathode. The cathode is constituted by a catalyst layer formed to tightly contact the surface of the electrolyte membrane and having a maximum thickness that is one to three times the height of the projection or the depth of the depression. An oxygen-containing gas having a relative humidity of 10% or less is supplied to the cathode, and electric power is generated by using the polymer electrolyte fuel cell.

Abstract: In order to significantly improve power generation efficiencies for the fuel cells, the present invention provides a method for fabricating a polymer electrolyte membrane comprising a surface with an array of a plurality of fine convex portion with a depth of not less than 3 ?m and not more than 12 ?m and an aspect ratio of not less than 0.4 and not more than 2.0, said method comprising the steps of (A) to (E), (A) preparing a mold comprising a surface with an array of a plurality of fine concave portions, wherein, each of said fine concave portions comprises a bottom and a side wall, each of said bottoms and said side walls are hydrophilic, each of side walls is smooth, each of said concave portions has a depth of not less than 3 ?m and not more than 12 ?m and an aspect ratio of not less than 0.4 and not more than 2.

Abstract: An oxygen electrode used in the fuel cell and includes a plurality of carbon particles, a carbon thin-film, and surface nanostructure. The carbon particles are bonded to one another with the carbon thin-film, and the surface nanostructure is formed on the surface of the carbon thin-film. The surface nanostructure comprises catalyst nanoparticles made of platinum (Pt) and carbon nanoparticles. According to this combination of these elements, the catalyst nanoparticles are confined within three-dimensional structure to be formed by the carbon nanoparticles and are immobilized without losing space which allows any reactant to be accessed to the surface of the catalyst nanoparticles.

Abstract: A polymer electrolyte fuel cell includes a cathode, an anode, and an electrolyte membrane sandwiched between the cathode and the anode. A plurality of projections each having a height of 5 to 15 ?m or a plurality of depressions each having a depth of 5 to 15 ?m are formed on a surface of the electrolyte membrane, the surface being opposed to the cathode. The cathode is constituted by a catalyst layer formed to tightly contact the surface of the electrolyte membrane and having a maximum thickness that is one to three times the height of the projection or the depth of the depression. An oxygen-containing gas having a relative humidity of 10% or less is supplied to the cathode, and electric power is generated by using the polymer electrolyte fuel cell.