Development of the measuring method of sublimable boron compound concentration in plant emission gas and in the environmental atmosphere.

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The plant damage due to by the boron compound in the atmosphere has caused. There is no precedent for this in the world. There are some examples about the plant damage of a basin system, and the environmental standard for water quality is definite. However, since the plant damage by the boron compounds in the atmosphere has not been reported, there is no legal regulation system, and the measuring method is not established in the present stage.We have immediately developed an extracting method in the outside of flue (currently used the type-II stack sampler) for the measurement of gas phase boron compounds. However, due to the sublimable nature of born compounds, the measurements vary widely and the reproducibility was low.Therefore, we developed the method of extracting directly within a flue (the type-II stack sampler). This method is not influenced by the sublimable nature of boron compounds in the emission gas. Furthermore this method is hardly influenced by the partial pressure and … More also by the temperature difference between the inside and outside of flue. At the same time, we examined the most suitable collection agent.An artificial stack chamber is used for the examination of measuring method.The very small filter holder made from SUS (for 25mmefilter paper) was directly inserted into the stack chamber. Teflon filter was used for the 1st step collection of particles, and alkali impregnated filter papers were set to the 2nd and the 3rd steps for collection of gaseous boron compounds. The collection was carried out for 1 hour by 1L/min. The collection papers were treated with the ultrasonic extraction by ultrapure water, filtered with a disposable filter, and measured with an ICP-mass spectrometer. Six kinds of alkali impregnation disposable filter papers (potassium carbonate, sodium carbonate, lithium hydroxide, barium hydroxide, calcium carbonate, and magnesium hydroxide) were examined in the 2005 or 2006 fiscal years.Since we used cellulose filters in these years, the maximum temperature of the artificial stack was forced down to 70-C. It is generally known that the practical stack temperature is about 180℃. Therefore, in the 2007 fiscal year, we used the heat-resistant gasket made from aluminum, and examined the heat-resistant quartz fiber filter papers of potassium carbonate and sodium carbonate impregnated. As a result, the heat-resisting properties of these impregnation quartz fiber filter papers were confirmed and the measurement became possible. Less