摘要:
In the method for manufacturing a SIMOX wafer, oxygen ions are implanted into a silicon wafer, then the silicon wafer is subjected to a prescribed heat treatment so as to form a buried oxide layer in the silicon wafer. The prescribed heat treatment includes: a step of ramping up a temperature of the silicon wafer in a low oxygen partial pressure gas atmosphere having an oxygen partial pressure ratio of less than 5%; either or both of a step of oxidizing the silicon wafer in a high oxygen partial pressure gas atmosphere having an oxygen partial pressure ratio of 5% or more and a step of annealing the silicon wafer in a low oxygen partial pressure gas atmosphere having an oxygen partial pressure ratio of less than 5%; and a step of ramping down the temperature of the silicon wafer in a low oxygen partial pressure gas atmosphere having an oxygen partial pressure ratio of less than 5%. A hydrogen chloride gas is mixed with the low oxygen partial pressure gas having an oxygen partial pressure ratio of less than 5% in at least one step from among the ramp-up step, the anneal step and the ramp-down step.
摘要:
A rotational position sensor having a compact and simple structure, in which a magnetic surface can be formed to have a more accurate shape, and an electronically controlled throttle device for an internal combustion engine, which employs the rotational position sensor. The rotational position sensor comprises a pair of substantially half disk-shaped magnetic cores disposed in an opposed relation to each other with a magnetic sensitive device interposed therebetween, a pair of substantially arc-shaped magnetic cores disposed in an opposed relation to each other along outer peripheries of the half disk-shaped magnetic cores, and a permanent magnet fixed in contact with at least one of the arc-shaped magnetic cores. Magnetic flux generating from the permanent magnet flows successively through one of the arc-shaped magnetic cores, the half disk-shaped magnetic cores, and the other of the arc-shaped magnetic cores, followed by returning to the permanent magnet. The half disk-shaped magnetic cores or the permanent magnet is rotatable, and the magnetic sensitive device detects an amount of the magnetic flux varying with rotation of the half disk-shaped magnetic cores or the permanent magnet.
摘要:
A rotational position sensor having a compact and simple structure, in which a magnetic surface can be formed to have a more accurate shape, and an electronically controlled throttle device for an internal combustion engine, which employs the rotational position sensor. The rotational position sensor comprises a pair of substantially half disk-shaped magnetic cores disposed in an opposed relation to each other with a magnetic sensitive device interposed therebetween, a pair of substantially arc-shaped magnetic cores disposed in an opposed relation to each other along outer peripheries of the half disk-shaped magnetic cores, and a permanent magnet fixed in contact with at least one of the arc-shaped magnetic cores. Magnetic flux generating from the permanent magnet flows successively through one of the arc-shaped magnetic cores, the half disk-shaped magnetic cores, and the other of the arc-shaped magnetic cores, followed by returning to the permanent magnet. The half disk-shaped magnetic cores or the permanent magnet is rotatable, and the magnetic sensitive device detects an amount of the magnetic flux varying with rotation of the half disk-shaped magnetic cores or the permanent magnet.
摘要:
A condenser for use in a power plant includes a steam condensing zone having a heat exchanger tube bundle for condensing steam into condensate and a hot well zone allowing the condensate to stay therein. A plurality of detectors for detecting the quality of the condensate and/or detection ports for taking out a sample of the condensate are provided in the hot well zone. The control valve is provided on a feed water system for adjusting the supply of the condensate to be supplied from the condenser to the feed water system on the basis of water quality detection values detected by the plurality of detectors and/or detection ports and a make-up water system is provided for supplying make-up water to the feed water system on the downstream side of the control valve.
摘要:
An object of the present invention is to provide a turbine protection device which can interrupt backflow from a deaerator to a turbine completely even if a check valve provided between the deaerator and the turbine can not interrupt the steam flow between the deaerator and the turbine completely. In order to achieve the above object, a control unit sends commands to a shutdown valve device so as to close the shutdown valve device when a differential pressure resulted from subtracting a pressure of a extraction steam from a pressure within the deaerator becomes greater than or equal to a first predetermined value. As a result, the backflow from the deaerator to the turbine is interrupted by a stop valve of the shutdown valve device.
摘要:
Water quality detecting points for detecting sea water leakage are provided at a portion in a hot well zone right under a tube bundle of heat exchange tube forming a steam condensing zone and at a condenser outlet allowing the condensate to be led out of the condenser or in the vicinity thereof, and a difference between detection values at both detecting points is monitored. Further, when leakage of sea water occurred, a feed water stop valve or a condensate stop valve is stopped for separating the system in which the sea water is mixed, and at same time, make-up water is supplied to a steam generator. Further, chemical or chemical dilution water is injected into the condensate mixed with sea water.