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Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of ethylene glycol in industry is introduced・ The process of preparing ethylene glycol from ethanolaldehyde is reviewed，including fbrmylation and hydrogenation of formaldehyde，cellulose pyrolysis and formaldehyde condensation. It is pointed out that the preparation of ethylene glycol by formaldehyde condensation has great advantages and is a direction of development in the future. [ABSTRACT FROM AUTHOR]

1,3-Butanediol is an intermediate to produce products and can be used in chemical industry, medicine, and cosmetic. The paper summarizes the production of 1, 3-butanediol by two chemical syntheses, including acetaldehyde aldol condensation and hydrogenation, formaldehyde propylene condensation hydrolysis via Prins reaction. The research directions of the two processes in the future are also suggested. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 To provide a method reference for the analysis and determination standards of sulfur dioxide in herb tea, a test method of sulfur dioxide by ion chromatography was established. 【Method】 Samples of herb tea were distilled under acidic conditions, and the sulfur dioxide produced was absorbed into hydrogen peroxide solution, and then was oxidized into sulfate ion. The solution was filtered with 0.22μm filtering menbrane, and the filtrate was separated on AG11-HC protective column and AS11-HC separation column. Chromatographic conditions of the eluent concentration and flow rate were optimized with ion chromatography-conductance detection mode. 【Result】 The optimum chromatographic condition was using 30.00 mmol·L-1 KOH as the eluent at a flow rate of 1.00 m L·min-1.Under this condition, sulfate standard curve correlation was good in the range from 3.60 mg·L-1 to 36.00 mg·L-1（r = 0.9998）, the detection limit of the method was 0.06 mg·L-1. Values of recovery rate were in the range of 80.89%-93.61%, and values of RSD’s（ n = 3） were found in the range of 2.45%-4.85%. 【Conclusion】 The indirect method by ion chromatography is simple and sensitive, which is suitable for the determination of sulfur dioxide in herb tea. [ABSTRACT FROM AUTHOR]

Copyright of Guihaia is the property of Guihaia Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)