Abstract: According to one embodiment, a three-dimensional object includes a periodic structure. The periodic structure includes a plurality of unit objects which form a plurality of stepped structures connected to each other. In each of the stepped structures, the unit objects are connected together in a stepwise form along a polygonal spiral trajectory around a unit axis. In each of the stepped structures, the unit axis extends in a first direction. The stepped structures are each provided with a unit channel extending along the connected unit objects of the stepwise form. The periodic structure is provided with a channel in communication with an outside of the periodic structure, the channel including the unit channels.

Abstract: According to one embodiment, a cooling device includes a heat releasing element including a surface configured to contact a heat generating element and an internal fluid channel configured to flow a cooling medium. The cooling device also includes a plurality of cooling fins within the fluid channel, each of which extends in a direction crossing a flow direction of the cooling medium and has a zigzag, corrugated shape defined by multiple bent portions.

Abstract: According to one embodiment, a cooling device includes a heat releasing element including a surface configured to contact a heat generating element and an internal fluid channel configured to flow a cooling medium. The cooling device also includes a plurality of cooling fins within the fluid channel, each of which extends in a direction crossing a flow direction of the cooling medium and has a zigzag, corrugated shape defined by multiple bent portions.

Abstract: An electrochemical cell according to one embodiment includes a solid electrolyte layer having insulating property, a first electrode, and a second electrode. The solid electrolyte layer has a first face and a second face, and allows ions to move therethrough. The first electrode is one of an anode and a cathode and provided on the first face. The first electrode includes an inside channel that allows gas to flow, a third face into which a first open end of the channel opens, a fourth face into which a second open end of the channel opens, and an inner wall face that defines the channel. The second electrode is the other of the anode and the cathode and provided on the second face.

Abstract: An electrochemical cell according to one embodiment includes a solid electrolyte layer having insulating property, a first electrode, and a second electrode. The solid electrolyte layer has a first face and a second face, and allows ions to move therethrough. The first electrode is one of an anode and a cathode and provided on the first face. The first electrode includes an inside channel that allows gas to flow, a third face into which a first open end of the channel opens, a fourth face into which a second open end of the channel opens, and an inner wall face that defines the channel. The second electrode is the other of the anode and the cathode and provided on the second face.