Abstract: A vacuum control system allows the degree of vacuum in a vacuum vessel to be kept constant while removing vaporized components degassed into the vacuum vessel through a gas permeation diaphragm by stably introducing a very small amount of air into a vacuum exhaust path of the vacuum vessel. The vacuum control system controls the rotary power of a DC brushless motor, continuously controls displacement of a vacuum pump, and thus keeps the degree of vacuum in a vacuum vessel constant, by decompressing the inside of the vacuum vessel using an exhaust vacuum pump which operates with the DC brushless motor, monitoring the inside pressure of the vacuum vessel using a pressure sensor, and controlling a voltage applied to the DC brushless motor on the basis of an output signal resulting from measurement of the inside pressure of the vacuum vessel by the pressure sensor.

Abstract: There is provided a vacuum control system for allowing the degree of vacuum in a vacuum vessel to be kept constant, effectively and accurately removing vaporized components degassed into the vacuum vessel through a gas permeation diaphragm by stably introducing a very small amount of air into a vacuum exhaust path, and thus operating stably, and a vacuum degassing apparatus employing the vacuum control system. The vacuum control system controls the rotatory power of a DC brushless motor, continuously controls displacement of a vacuum pump, and thus keeps the degree of vacuum in a vacuum vessel constant, by decompressing the inside of the vacuum vessel using an exhaust vacuum pump which operates with the DC brushless motor, monitoring the inside pressure of the vacuum vessel using a pressure sensor, and controlling a voltage applied to the DC brushless motor on the basis of an output signal resulting from measurement of the inside pressure of the vacuum vessel by the pressure sensor.

Abstract: This invention's object is to eliminate a possibility that both aromatic substances and olefin substances are resolved into deaerated liquid contacted with a transmission film. As a transmission film for allowing only gas to pass and preventing liquid from being passed therethrough, there is applied a product of high volatile characteristic in which dispersion liquid composed of single solution is added to particle plastic substrate to form paste material is extruded and baked.

Abstract: This invention's object is to eliminate a possibility that both aromatic substances and olefin substances are resolved into deaerated liquid contacted with a transmission film. As a transmission film for allowing only gas to pass and preventing liquid from being passed therethrough, there is applied a product of high volatile characteristic in which dispersion liquid composed of single solution is added to particle plastic substrate to form paste material is extruded and baked.

Abstract: To provide a differential refractive index detector free from fears for occurrence of personal errors in the judgement of stable condition and capable of performing highly efficient analysis operation, and a liquid chromatograph equipped with the detector.

Abstract: A treatment composition for treating contaminated material is disclosed which has water, coal, and an alkali metal carbonate. In another aspect an additional ingredient is a seaweed derivative. A method for making such a treatment composition for treating contaminated material has been developed which includes introducing water into a first tank, blending in alkali metal carbonate in the first tank with the water to form a first composition, adding coal to the first composition and blending them together forming a base composition, introducing one half of the base composition from the first tank into a second tank, introducing an amount of seaweed derivative into the second tank equal in volume to the amount of base composition in the second tank, and blending the contents of the second tank together producing the treatment composition.