Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of particles of the fine particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. Specifically disclosed are a method of producing particulate sodium-potassium niobate represented by the formula (1): NaxK(1-x)NbO3 (1), the method including four specific steps, wherein a high-concentration alkaline solution containing Na+ ion and K+ ion is used as an alkaline solution; and particulate sodium-potassium niobate having a controlled shape and size.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of particles of the fine particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. Specifically disclosed are a method of producing particulate sodium-potassium niobate represented by the formula (1): NaxK(1-x)NbO3 (1), the method including four specific steps, wherein a high-concentration alkaline solution containing Na+ ion and K+ ion is used as an alkaline solution; and particulate sodium-potassium niobate having a controlled shape and size.

Abstract: Provided is a piezoelectric generating element having an electrode on an outer surface of a piezoelectric ceramic body, wherein the piezoelectric ceramic body has a relative permittivity of 110 to 1700, an elastic compliance of 15 to 150 pm2/N, and a void ratio of 20 to 75%. Preferably, the void ratio is 50 to 75% in the piezoelectric generating element. A crystal particle is modeled as a cube with a length X on a side, a virtual void portion is provided in cube, a void ratio x is calculated based on a thickness t of a frame excluding void portion, a relative permittivity ?r and an elastic compliance s are calculated based on void ratio x, and a power generation amount P is estimated. Thereby, a piezoelectric generating element capable of significantly increasing a power generation amount more than before, and a method for estimating a power generation amount of the piezoelectric generating element can be obtained.

Abstract: Provided is a piezoelectric generating element having an electrode on an outer surface of a piezoelectric ceramic body, wherein the piezoelectric ceramic body has a relative permittivity of 110 to 1700, an elastic compliance of 15 to 150 pm2/N, and a void ratio of 20 to 75%. Preferably, the void ratio is 50 to 75% in the piezoelectric generating element. A crystal particle is modeled as a cube with a length X on a side, a virtual void portion is provided in cube, a void ratio x is calculated based on a thickness t of a frame excluding void portion, a relative permittivity ?r and an elastic compliance s are calculated based on void ratio x, and a power generation amount P is estimated. Thereby, a piezoelectric generating element capable of significantly increasing a power generation amount more than before, and a method for estimating a power generation amount of the piezoelectric generating element can be obtained.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of particles of the fine particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. Specifically disclosed are a method of producing particulate sodium-potassium niobate represented by the formula (1): NaxK(1-x)NbO3 (1), the method including four specific steps, wherein a high-concentration alkaline solution containing Na+ ion and K+ ion is used as an alkaline solution; and particulate sodium-potassium niobate having a controlled shape and size.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.

Abstract: A knock sensor of the invention includes a base having a cylindrical part mounted on a vibration generating part and a flange part, an annular piezoelectric element fitted to the cylindrical part and for converting a knocking vibration of the vibration generating part into an electric signal to detect it, electrodes respectively provided to be in contact with both surfaces of the piezoelectric element, terminal plates disposed to be in contact with the respective electrodes and for extracting an output of the piezoelectric element to outside, and a hold unit for pressure holding the piezoelectric element, the electrodes and the terminal plates to the flange part, in which a conductive adhesive material having an almost equal thickness to the electrode is provided on a portion of the piezoelectric element which is not in contact with the electrode.

Abstract: A knock sensor of the invention includes a base having a cylindrical part mounted on a vibration generating part and a flange part, an annular piezoelectric element fitted to the cylindrical part and for converting a knocking vibration of the vibration generating part into an electric signal to detect it, electrodes respectively provided to be in contact with both surfaces of the piezoelectric element, terminal plates disposed to be in contact with the respective electrodes and for extracting an output of the piezoelectric element to outside, and a hold unit for pressure holding the piezoelectric element, the electrodes and the terminal plates to the flange part, in which the electrodes are provided to be in partial contact with the piezoelectric element, and an electric insulating material having an almost equal thickness to the electrode is provided on a portion of the piezoelectric element which is not in contact with the electrode.