Abstract: In the radio communication control of the slave telephone set with a unit ID in one-to-one correspondence to one slave telephone set, in order to assign two or more communication channels to one slave telephone set for radio communication, a plurality of unit IDs are registered in each slave telephone set are also registered in the master telephone set.

Abstract: In a method of establishing callback communication between first and second terminals via a relay station, the first terminal sends a callback request for establishing the callback communication to the second terminal. The method comprises the steps of: (1) establishing first connection between the first terminal and the relay station; (2) sending the callback request from the first terminal to the relay station; (3) establishing second connection between the second terminal and the relay station with the first connection being kept established in response to a request from the second terminal; and (4) linking the first connection with the second connection in order to establish the callback communication between the first and second terminals. Further, a relay station performing the method is also provided. This method dispenses with any identifier for identifying the first terminal on performing the callback.

Abstract: The present invention provides a hollow fiber membrane module of immersing type in which it is difficult for polluted substances to accumulate between hollow fiber membranes, and increase in pressure difference, reduction in flow rate and inter-fiber clogging can be prevented for a long time period. The module is provided at its both ends with water collecting portions having water collecting plates, and hollow fiber membranes are connected to the water collecting plates in such a manner that the hollow fiber membranes are not in contact with each other, and the hollow fiber membranes are mounted between the plates in a relaxed condition.

Abstract: The present invention provides a hollow fiber membrane module of immersing type and a method for manufacturing such a hollow fiber membrane module, in which it is difficult for polluted substances to accumulate between hollow fiber membranes, and increase in pressure difference, reduction in flow rate and inter-fiber clogging can be prevented for a long time period. The module is provided at its both ends with water collecting portions having water collecting plates, and hollow fiber membranes are connected to the water collecting plates in such a manner that the hollow fiber membranes are not in contact with each other, and the hollow fiber membranes are mounted between the plates in a relaxed condition.

Abstract: The present invention provides a method by which harmful trace gases in a gaseous mixture containing as such harmful halogen gases, halogenated hydrogen gases, acid gases, oxidizing gases, basic gases, organic acid gases, especially halogen gases or halogenated hydrogen gases, are detected by using tetraphenylporphyrin (TPP) and quantitated from a calibration curve constructed therefrom, where the range of detectable concentration is made adjustable so that harmful gas can be detected and quantitated over a broad range of concentration. Furthermore, this invention also provides a method for extending the accessible range of gas concentration by adjusting the sensitivity of the detector material via control of tetraphenylporphyrin concentration in matrix polymer of the detector material, by controlling the gas concentration range via measurement at a specific wavelength(s), and by the use of a plurality of detector materials with pre-set assay sensitivity.

Abstract: This invention provides a method for determining the concentration of a gas to be detected by a gas detector using a gas reactive pigment, wherein the dynamic range of the detectable concentration can be controlled. The method comprising bringing a gas to be detected such as a halogen gas, a hydrogen halide gas or the like into contact with a gas detector placed in a detection area and comprising a gas reactive pigment tetraphenylporphyrin or a derivative thereof represented by the general formula (1) or a metal complex of tetraphenylporphyrin or a derivative thereof represented by the general formula (2); and irradiating said gas detector with a detection beam and measuring a color change in said gas detector to determine the concentration of said gas to be detected, wherein the measurement is carried out in the temperature range from 40 to 80.degree. C. of said detection area; and a detection apparatus for carrying out the said method are disclosed.

Abstract: The present invention provides a method by which harmful trace gases in a gaseous mixture containing as such harmful halogen gases, halogenated hydrogen gases, acid gases, oxidizing gases, basic gases, organic acid gases, especially halogen gases or halogenated hydrogen gases, are detected by using tetraphenylporphyrin (TPP) and quantitated from a calibration curve constructed therefrom, where the range of detectable concentration is made adjustable so that harmful gas can be detected and quantitated over a broad range of concentration. Furthermore, this invention also provides a method for extending the accessible range of gas concentration by adjusting the sensitivity of the detector material via control of tetraphenylporphyrin concentration in matrix polymer of the detector material, by controlling the gas concentration range via measurement at a specific wavelength(s), and by the use of a plurality of detector materials with pre-set assay sensitivity.