Abstract: An ultrasonic radiator includes a plurality of plate-like elements, a supporter, and a first adhesive. The plurality of plate-like elements each have, on the front side or the back side, a radiation surface from which ultrasonic waves are emitted. The supporter holds the plurality of plate-like elements in such a manner that the respective radiation surfaces in different directional orientations are directed toward the same location. The plurality of plate-like elements are bonded to the supporter with the first adhesive. The plurality of plate-like elements each include a plurality of vibratory elements that are variously located in the radiation surface and that generate ultrasonic waves. The first adhesive is applied to lateral surfaces of each of the plurality of plate-like elements.

Abstract: By a microbial fuel cell including: an anode electrode that includes, as a catalyst, current-generating bacteria supplied from soil or mud, and oxidizes an organic fuel supplied from soil or mud; and a cathode electrode that reduces oxygen supplied from air or water, the microbial fuel cell having an oxygen permeation restricting layer between the anode electrode and the cathode electrode facing each other, it is possible to provide, at low cost, a microbial fuel cell having high power generation performance due to direct power generation from soil or mud and capable of being thinned and miniaturized.

Abstract: Provided is a microbial fuel cell which is capable of stably generating electricity and in which a pump or the like for fuel supply is not necessary and low oxygen concentration is maintained in the vicinity of a fuel electrode. A microbial fuel cell (1A) includes: a housing (2) that defines a closed space isolated from an external environment; and an ion-conductive layer (5) that divides the closed space into a fuel chamber (3) and an air chamber (4), the fuel chamber (3) being configured to have therein a microorganism-containing substance (10), the air chamber (4) containing oxygen therein. The housing (2) has, in at least part thereof, a hole (6) through which the external environment and the fuel chamber (3) are in communication with each other. The housing (2) is provided with an openable/closeable member (7) configured to be able to open and close the hole (6).

Abstract: A change in electromotive force of a microbial fuel cell is sensed and visualized by use of electric supply from the microbial fuel cell. A sensing section (8) and an output section (9) are configured to be powered by the electromotive force of a microbial fuel cell (100).

Abstract: By a microbial fuel cell including: an anode electrode that includes, as a catalyst, current-generating bacteria supplied from soil or mud, and oxidizes an organic fuel supplied from soil or mud; and a cathode electrode that reduces oxygen supplied from air or water, the microbial fuel cell having an oxygen permeation restricting layer between the anode electrode and the cathode electrode facing each other, it is possible to provide, at low cost, a microbial fuel cell having high power generation performance due to direct power generation from soil or mud and capable of being thinned and miniaturized.