Abstract: To provide a method for producing a fluorinated copolymer, whereby it is possible to efficiently produce a fluorinated copolymer in which coloration and foaming are suppressed during heating. A method for producing a fluorinated copolymer, comprising a step of producing a fluorinated copolymer by polymerizing tetrafluoroethylene and other monomer other than the tetrafluoroethylene in the presence of a hydroperoxide, at least one selected from the group consisting of a sulfite, a hydrogen sulfite, a dithionite, and a metabisulfite, at least one selected from the group consisting of an acidic substance and a substance that generates an acid by hydrolysis, and an aqueous medium.

Abstract: A fluid level detection apparatus includes a vibrator, a vibration sensor, and a controller. The vibrator is configured to apply a vibration to a container that contains a fluid. The vibration sensor is configured to detect a vibration wave that is generated by the vibrator and propagates through the container. The controller is configured to control an operation of the vibrator and perform arithmetic processing on a detection signal obtained from the vibration sensor. The vibrator and the vibration sensor are provided on an outer wall surface of the container at respective positions that interpose, from above and below, a fluid level of the fluid provided in the container. The controller is configured to calculate a height of the fluid level, on the basis of the vibration wave detected by the vibration sensor.

Abstract: A fluid level detection apparatus includes a vibrator, a vibration sensor, and a controller. The vibrator is configured to apply a vibration to a container that contains a fluid. The vibration sensor is configured to detect a vibration wave that is generated by the vibrator and propagates through the container. The controller is configured to control an operation of the vibrator and perform arithmetic processing on a detection signal obtained from the vibration sensor. The vibrator and the vibration sensor are provided on an outer wall surface of the container at respective positions that interpose, from above and below, a fluid level of the fluid provided in the container. The controller is configured to calculate a height of the fluid level, on the basis of the vibration wave detected by the vibration sensor.

Abstract: A method for producing a molten glass conveying equipment element. The molten glass conveying equipment element has a conduit structure for molten glass containing at least one conduit comprising platinum or a platinum alloy, a first ceramic structure provided around the conduit and a second ceramic structure located around the first ceramic structure. The method includes filling a gap between the conduit and the second ceramic structure with a slurry body, and sintering the slurry body at a temperature of 1,300 to 1,550° C., thereby forming the first ceramic structure. The slurry body is prepared by blending specific first particles, specific second particles and specific third particles with specific mass ratios.

Abstract: A method for producing a molten glass conveying equipment element. The molten glass conveying equipment element has a conduit structure for molten glass containing at least one conduit comprising platinum or a platinum alloy, a first ceramic structure provided around the conduit and a second ceramic structure located around the first ceramic structure. The method includes filling a gap between the conduit and the second ceramic structure with a slurry body, and sintering the slurry body at a temperature of 1,300 to 1,550° C., thereby forming the first ceramic structure. The slurry body is prepared by blending specific first particles, specific second particles and specific third particles with specific mass ratios.