Abstract: A hydrogen supply method includes a two-side heat exchange mode in which both introducing a second fluid into a hydrogen storage part after the second fluid exchanges heat with a first fluid in a second heat exchanger in a state in which a compressor is driven to compress the first fluid and introducing the second fluid into the hydrogen storage part after the second fluid is heated or cooled in a thermal device are performed. The method also includes a one-side heat exchange mode in which one of introducing the second fluid into the hydrogen storage part after the second fluid exchanges heat with the first fluid in the second heat exchanger in a state in which the compressor is driven to compress the first fluid and introducing the second fluid into the hydrogen storage part after the second fluid is heated or cooled in the thermal device is performed.

Abstract: A hydrogen compression system includes: a heat pump part including a heat pump line configured to allow a refrigerant to circulate therethrough, a hydrogen compression part configured to compress hydrogen by being repeatedly heated and cooled, a first circulation line connected to the heat pump line while passing through the hydrogen compression part and configured to allow the refrigerant introduced from the heat pump line to circulate therethrough, a second circulation line provided to pass through the hydrogen compression part and configured to allow a cooling fluid to circulate therethrough, and a cooling unit provided in the second circulation line and configured to cool the cooling fluid, in which the hydrogen compression part is heated by the refrigerant or cooled by the cooling fluid, thereby minimizing electric power consumption and improving energy efficiency.

Abstract: A hydrogen storage system is disclosed and includes a storage unit including a plurality of unit storage containers, in which metal hydride materials are respectively provided in an interior thereof and which are connected to each other in parallel, and a thermal fluid line defining a thermal fluid passage, which passes via the plurality of unit storage containers continuously and through which a thermal fluid flows for heating or cooling the unit storage containers, thereby enhancing a storage performance and an efficiency of the hydrogen.

Abstract: A hydrogen storage device includes a storage container having an accommodation space in an interior thereof, a first metal hydride material provided in the interior of the storage container and that stores hydrogen, and a second metal hydride material provided in the interior of the storage container and that stores the hydrogen at a pressure that is different from that of the first metal hydride material. An advantageous effect of restraining an excessive rise of a pressure of the storage container and enhancing safety and reliability may be obtained.

Abstract: A spiral phase plate, according to one embodiment, for generating a Laguerre Gaussian beam by reflecting an incident beam emitted from a light source, may comprise: a first quadrant area in which the step height increase rate per unit angle decreases progressively in one direction from the point with the lowest step height to the point with the highest step height; and a second quadrant area in which the step height increase rate per unit angle increases progressively in the one direction.

Abstract: A carbon nitride heterogeneous catalyst containing rhodium, a method for preparing the catalyst, and a method for preparing acetic acid using the catalyst is disclosed. The heterogeneous catalyst is characterized in that the rhodium metal is contained in carbon nitride which is a support insoluble in a liquid solvent, such as water or alcohol. Thus, the catalyst can easily be separated from a resulting product even by a simple process such as filtration. Accordingly, the carbon nitride heterogeneous catalyst exhibits excellent long-term stability and activity by being capable of overcoming the disadvantages of the method using a conventional homogeneous catalyst and minimizing the phenomenon of rhodium leaching, compared to the results of the conventional homogeneous catalytic reactions. The catalyst can thus be effectively used for the preparation of acetic acid by a carbonylation reaction between methanol and carbon monoxide.

Abstract: A carbon nitride heterogeneous catalyst containing rhodium, a method for preparing the catalyst, and a method for preparing acetic acid using the catalyst is disclosed. The heterogeneous catalyst is characterized in that the rhodium metal is contained in carbon nitride which is a support insoluble in a liquid solvent, such as water or alcohol. Thus, the catalyst can easily be separated from a resulting product even by a simple process such as filtration. Accordingly, the carbon nitride heterogeneous catalyst exhibits excellent long-term stability and activity by being capable of overcoming the disadvantages of the method using a conventional homogeneous catalyst and minimizing the phenomenon of rhodium leaching, compared to the results of the conventional homogeneous catalytic reactions. The catalyst can thus be effectively used for the preparation of acetic acid by a carbonylation reaction between methanol and carbon monoxide.