摘要:
The invention provides a method for manufacturing a large scale quartz glass slab ingot in a flame hydrolysis reaction in a furnace, including the steps of rotating the furnace, depositing a fused silica on a furnace bed, and extending the deposit outwardly by heating and rotation of the furnace, thereby a quartz glass slab ingot is obtained. A quartz glass burner is installed at the ceiling of the furnace, hydrogen gas supplied to the burner flows down along the tapered wall of the oxygen chamber and is ejected into the outer casing. Part of the hydrogen gas is deflected to the center of the burner and mixed with the oxygen just after the ejection from the oxygen gas nozzles. Thereby, the flame is formed smoothly and the thermal efficiency is improved. The flame becomes wide enough and the silica powder transported by the hydrogen gas is uniformly fused by the flame and heat capacity of the fused silica.
摘要:
A first positioning enclosure of a touch panel holder frame is attached to a display device body to surround an outer periphery of a display screen. A second positioning enclosure is attached to the display device body to surround an outer periphery of a touch panel. Holding pawl sections provided on an inner surface of the second positioning enclosure engage the outer periphery of the touch panel to prevent the touch panel from coming out of the touch panel holder frame. A spacer section extends between the first and second positioning enclosures to define a given clearance between the display screen and the touch panel.
摘要:
A piezoelectric resonator includes a substrate and a vibrator. The vibrator includes a thin-film portion having at least one piezoelectric thin-film layer disposed on the substrate and at least one pair of upper and lower electrodes disposed on the substrate. The vibrator has a structure in which the thin-film portion is sandwiched from the upper and lower surfaces thereof by the upper and lower electrodes, which oppose each other in the depth direction, and the overlapping portion of the vibrator defined by the opposing upper and lower electrodes has a tetragonal shape, when viewed in the depth direction, other than a rectangle and a square, the tetragonal shape having substantially parallel sides having a longitudinal length equal to or smaller than about 10 times the oscillatory wavelength and also having at least one portion in which the distance between opposing electrode edges varies.
摘要:
A duplexer includes a transmission band filter and a reception band filter connected in parallel to each other and connected to an antenna terminal. The transmission band filter and the reception band filter are accommodated in a package covered with an electroconductive lid. The package is mounted on a mounting substrate having the antenna terminal and covered with an electroconductive shield mounted on the mounting substrate. At least one of the transmission band filter and the reception band filter has a ground terminal connected to the lid. The lid is electrically connected to the shield.
摘要:
The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes the steps of (a) adding hydrogen fluoride to 1-chloro-3,3,3-trifluoropropene in the presence of an addition catalyst to obtain 1,1,1,3-tetrafluoro-3-chloropropane; and (b) disproportionating the 1,1,1,3-tetrafluoro-3-chloropropane into the 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3,3-dichloropropane, in the presence of a disproportionation catalyst. This method is a useful method for producing 1,1,1,3,3-pentafluoropropane in an industrial scale, because its steps (a) and (b) are respectively superior in selectivity and yield. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. This method is useful, because yield of 1-chloro-3,3,3-trifluoropropene is high.
摘要:
The invention provides a process for easily, efficiently and economically preparing bis(trifluoromethylphenyl)methanol from either toluoyl chloride or a trihalomethylbenzoyl chloride. First the starting compound is reacted with toluene in the presence of a strong acid catalyst such as a perfluoroalkylsulfonic acid to form a benzophenone derivative, CX.sub.3 C.sub.6 H.sub.4 --CO--C.sub.6 H.sub.4 CH.sub.3, wherein X is H, F, Cl or Br. Next, by chlorination the benzophenone derivative is converted into CY.sub.3 C.sub.6 H.sub.4 --CO--C.sub.6 H.sub.4 CCL.sub.3, wherein Y is F or Cl, and then the chlorinated intermediate is fluorinated into bis(trifluoromethyl)benzophenone. By reduction of carbonyl group of this benzophenone derivative the aimed compound is obtained.
摘要:
An isomer mixture of 4-trifluoromethyl-2-nitrobenzoic acid and 4-trifluoromethyl-3-nitrobenzoic acid, which is a novel compound, is obtained by nitrating a compound represented by ##STR1## (Z is COY or CY.sub.3, and Y is a halogen atom) with a nitrating agent comprising nitric acid and simultaneously hydrolyzing the radical Z. Each of the two isomers is easily isolated by treating the mixture with a basic neutralizing agent to obtain a solution containing the 2-nitro isomer and a precipitate containing the 3-nitro isomer.
摘要:
A piezoelectric thin-film resonator includes a supporting substrate. A piezoelectric thin-film is formed on the supporting substrate. A lower electrode and an upper electrode are formed with the piezoelectric thin-film therebetween. The stiffness of at least one of the lower and upper electrodes is higher than that of the piezoelectric thin-film.
摘要:
The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes a first step of fluorinating 1-chloro-3,3,3-trifluoropropene in a liquid phase by hydrogen fluoride in the presence of an antimony compound as a catalyst, or a second step of fluorinating 1-chloro-3,3,3-trifluoropropene in a gas phase by hydrogen fluoride in the presence of a fluorination catalyst. If the first step is taken, 1,1,1,3,3-pentafluoropropane can be produced with a high yield. If the second step is taken, 1,1,1,3,3-pentafluoropropane can continuously be easily produced. Therefore, the second step is useful for an industrial scale production thereof. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. This method is useful, because yield of 1-chloro-3,3,3-trifluoropropene is high.
摘要:
The present invention relates to a method for producing 1,1,1,3,3-pentafluoropropane. This method includes a step of adding hydrogen fluoride to 1,3,3,3-tetrafluoropropene in a liquid phase in the presence of a hydrohalogenation catalyst. This method is a useful method for producing 1,1,1,3,3-pentafluoropropane in an industrial scale, because yield of 1,1,1,3,3-pentafluoropropane is high. According to the invention, 1,3,3,3-tetrafluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst, or by another method including a step of reacting 1-chloro-3,3,3-trifluoropropene with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst. According to the invention, 1-chloro-3,3,3-trifluoropropene may be produced by a method including a step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst.