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Charles W. Gruber Charles E. Schumann 《Journal of the Air & Waste Management Association (1995)》2013,63(5):195-204
A fluoride analyzer originally designed by Wiggins, St. John, Thomas arid associates at Stanford Research Institute, has been modified to improve its operational capabilities and reliability so as to operate for periods in excess of six months with virtually no maintenance. It measures hydrogen fluoride in the atmosphere in the sub-parts per billion range. The need for the instrument, method of measuring fluoride and the modifications made to improve the SRI instrument are presented. The instrument has been operated in the field for two years beside impingers which obtain daily integrated samples. The impingers samples are subsequently titrated. Satisfactory correlation has been found between the average daily values by the automatic analyzer and the impinger. 相似文献