This process is a process for production of a vinyl chloride polymer by suspension polymerization or emulsion polymerization of vinyl chloride monomer or a mixture of vinyl chloride monomer with a vinyl monomer copolymerizable with said vinyl chloride monomer in an aqueous medium, characterized in that the polymerization is carried out in a polymerizer, the inner wall surface and portions of the auxiliary equipment thereof which may come into contact with the monomer during polymerization being previously coated with a scaling preventive comprising at least one selected from dyes, pigments and aromatic or heterocyclic compounds having at least 5 conjugated π bonds, while controlling the chloride ion concentration in the reaction mixture to not higher than 100 ppm. According to said process, scaling onto the inner wall surface of a polymerizer, etc. during polymerization can be prevented effectively and surely.
Corrosion inhibitor compositions for acidizing treatments
申请人:Lonza Inc.
公开号:US10059872B2
公开(公告)日:2018-08-28
A corrosion inhibitor composition and a method of inhibiting corrosion on a surface are disclosed. The corrosion inhibitor composition includes at least one nitrogen containing heteroaromatic compound and at least one haloalkynyl carbamate compound. The corrosion inhibitor composition may be utilized with acidizing treatments for wells, in particular for the production of oil, gas, and/or water.
Pre-analysis treatment method for sample containing plurality of components with greatly different concentrations
申请人:AiSTI SCIENCE CO., Ltd.
公开号:US10656126B2
公开(公告)日:2020-05-19
A pre-analysis treatment method includes: a first retaining step of supplying, to a solid phase, each predetermined amount of the sample and a first solvent, and allowing a component at low concentration to be retained in the solid phase; a first washing step of supplying the first solvent to the solid phase and removing a component at high concentration from the solid phase; a second retaining step of supplying the sample in a smaller amount than the predetermined amount supplied in the first retaining step, and a second solvent to the solid phase, and allowing the component at high concentration to be retained in the solid phase; and an elution step of simultaneously extruding the components retained in the solid phase with an extrusion solvent.