Abstract: A variable impeller for a pump is proposed. The variable impeller includes a hub to which a shaft is mounted, a plurality of vanes radially arranged around the hub outward from the hub, and extension wings tightly locked to the plurality of vanes and extending length of each of the vanes. The length of the vane is adjusted in response to the pumping head that is changed by a flow rate of fluid, the pump is operated within a high efficiency section, an expensive impeller rotation speed control device is not required, and energy is reduced by reducing power consumption of the pump. In addition, during the work of changing the pumping head, the replacement of the extension wings may be quickly completed while only a part of a pump housing is opened to expose only the impeller without separating the entire assembly of the impeller from the pump.

Abstract: The present invention relates to a press-type water sampling device, and to a press-type water sampling device comprising: a water sampling bottle having opened upper and lower parts; and a bumper support, which has a top cap and a bottom cap for blocking the opened upper and lower parts of the water sampling bottle, is formed into a frame having a shape that encompasses the water sampling bottle, and enables the water sampling bottle to be vertically moveable.

Abstract: The present invention relates to a highly efficient sodium hypochlorite generation apparatus capable of decreasing disinfection by-products, which is a chlorine disinfection device for on-site generation and produces sodium hypochlorite solution by electrolyzing sodium chloride aqueous solution on site, thereby requiring no additional liquefied chlorine storage equipment or disaster prevention equipment and securing flexibility of installation and operation while not being regulated by a high-pressure gas safety control act.

Abstract: Disclosed is a precipitation gauge including a precipitation receiving member having a water collecting part provided in a shape of a funnel at a lower portion of a cylindrical body and a drain tube, a photodetector installed on an inner sidewall of the cylindrical body to detect snow collected in the precipitation receiving member, heating parts installed on a bottom surface of the water collecting part and a wall of the drain tube to receive a snow signal detected by the photodetector for operation of the heating parts, a rotatable fluid supply unit coupled on a connection tube coupled with the drain tube of the precipitation receiving member perpendicularly to the drain tube, and a flow rate measuring unit provided in a discharge tube coupled with the connection tube provided at a lower portion of the rotatable fluid supply unit to measure a flow rate.

Abstract: Provided is a separation membrane for seawater desalination and a method for manufacturing the same, and more particularly, a separation membrane for seawater desalination with excellent water permeability and salt rejection and a method for manufacturing the same. If the separation membrane for seawater desalination and the method for manufacturing the same according to the present disclosure are applied, it is possible to provide a separation membrane for seawater desalination with excellent water permeability and salt rejection. Therefore, it is possible to provide a separation membrane for seawater desalination with improved performance in comparison to an existing separation membrane for seawater desalination. As a result, water resources may be widely utilized.

Abstract: An otter habitation section, an overland section, an inclined-surface section, a first spawning section, a second spawning section and a roost are all provided. Accordingly, otters and birds can sufficiently obtain preys, and fishes secure a spawning ground suitable for spawning characteristics. Therefore, the otters, the fishes and the birds can inhabit together. Further, since frames are made of wood for providing buoyant force or the frames are made of stainless steel for reinforcing strength and wood for providing buoyant force, a small amount of polyethylene foam is required. Accordingly, it is possible to obtain floating wetland equipment with a simple structure. Furthermore, the wooden frames itself provide a spawning ground of fishes.

Abstract: An otter habitation section, an overland section, an inclined-surface section, a first spawning section, a second spawning section and a roost are all provided. Accordingly, otters and birds can sufficiently obtain preys, and fishes secure a spawning ground suitable for spawning characteristics. Therefore, the otters, the fishes and the birds can inhabit together. Further, since frames are made of wood for providing buoyant force or the frames are made of stainless steel for reinforcing strength and wood for providing buoyant force, a small amount of polyethylene foam is required. Accordingly, it is possible to obtain floating wetland equipment with a simple structure. Furthermore, the wooden frames itself provide a spawning ground of fishes.

Abstract: The ozone-resistant polyurethane composition according to the present invention, which is for the linings of valves, pipes or ozone contactors used in advanced water-treatment plants, comprises: 100 parts by weight of a polyurethane prepolymer consisting of toluene diisocyanate and poly(tetramethylene ether)glycol; from 8 to 14 parts by weight of 6-methyl-2,4-bis(methylthio)phenylene-1,3-diamine; and from 0.8 to 2.8 parts by weight of benzophenone or benzotriazole. Also, the production method for the ozone-resistant polyurethane composition according to the present invention, which is for the linings of valves, pipes or ozone contactors used in advanced water treatment plants, comprises the steps of: mixing from 0.8 to 2.8 parts by weight of benzophenone or benzotriazole in 100 parts by weight of a polyurethane prepolymer consisting of toluene diisocyanate and poly(tetramethylene ether)glycol, and stirring for between 25 and 35 minutes at between 90 and 100° C.

Abstract: An apparatus for sampling a filter layer and a method using the same are disclosed herein. The apparatus includes a cylindrical tube made of a transparent material; a screw installed at a central portion in the cylindrical tube, to be rotated for shifting a sample from the lower part to the upper part of the cylindrical tube, and a rotary operating unit fixed to the upper end of the screw for rotating the screw, wherein the cylindrical tube is provided with a scale formed on its outer circumference and a protective cap combined with the lower end for smoothly excavating the filter layer and preventing the damage of the cylindrical tube. The apparatus further lower case a fixed supporter on the upper end of the screw and a supporting hand lever protruding from one side of the fixed supporter to be pressed by a worker with force required for excavation.