Abstract: A motor drive apparatus as a power conversion apparatus includes: a power conversion circuit that converts DC power to AC power and supplies resultant power to a motor; a control circuit that controls a plurality of switching elements that configures the power conversion circuit; a direct-current detection circuit that detects a direct current flowing into and out from the power conversion circuit; and an disconnection detection unit, configured by using a logic circuit, that detects an abnormality of one of the switching elements or a disconnection of one of power lines connecting the power conversion circuit to the motor on the basis of control signals output by the control circuit to the switching elements and a detection result obtained by the direct-current detection circuit.

Abstract: A flowmeter of the present invention is adapted to measure a flow velocity of a process liquid flowing through a supply pipe, and includes: a pair of ultrasonic oscillators located with a spacing therebetween of a predetermined distance along a flow direction of the supply pipe; a flow velocity calculating part calculating a flow velocity of the process liquid based on a first arrival time elapsed for an ultrasonic wave generated from one of the pair of ultrasonic oscillators to arrive at the other of the pair of ultrasonic oscillators and a second arrival time elapsed for an ultrasonic wave generated from the other of the pair of ultrasonic oscillators to arrive at the one of the pair of ultrasonic oscillators; and a bubble inclusion determining part determining, based on a time-varying amount of the calculated process liquid flow velocity, whether air bubbles are included in the process liquid.

Abstract: The present invention is an instrument that detects a trace amount of silicon contained in a sample solution with simple means and measures a silicon concentration in the sample solution, and adapted to include: an excitation light irradiation part that irradiates the sample solution with excitation light for silicon; a light detection part that detects fluorescence and/or scattering light emitted from silicon in the sample solution irradiated with the excitation light; and a calculation part that calculates the silicon concentration in the sample solution from intensities or an intensity of the fluorescence and/or the scattering light.

Abstract: A ell for analyzing fluid and an analyzing apparatus using the cell which can improve the degree of freedom as to the arrangement of the cell, be disposed at a small space, obtain a sufficient optical length by a small amount of sample, does not require a large-sized light shielding mechanism nor an additional many constituent parts and can change the optical length easily. In a cell C for analyzing fluid configured in a manner that sample S flows therein and irradiation light passes through the sample S, the cell includes an inner tube in which the sample S passes, a protection tube formed on the outside of the inner tube to hold the shape of the inner tube, and a reflection layer formed between the inner tube and the protection tube to reflect the light passing within the inner tube.

Abstract: A ell for analyzing fluid and an analyzing apparatus using the cell which can improve the degree of freedom as to the arrangement of the cell, be disposed at a small space, obtain a sufficient optical length by a small amount of sample, does not require a large-sized light shielding mechanism nor an additional many constituent parts and can change the optical length easily. In a cell C for analyzing fluid configured in a manner that sample S flows therein and irradiation light passes through the sample S, the cell includes an inner tube 9 in which the sample S passes, a protection tube 10 formed on the outside of the inner tube 9 to hold the shape of the inner tube 9, and a reflection layer 11 formed between the inner tube 9 and the protection tube 10 to reflect the light passing within the inner tube 9.