• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.1-5
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• 1996

Rapid analytical method was investigated to determine precursors of N-nitrosamine such an nitrite and nitrate in squid(Illex illecebrosus and Sepiell maindroni), codfish(Gadus marcrocephalus)and flatfish(Paralichthys olivaceus) by ion chromatography(IC) and colorimetric methods. Recoveries of nitrite and nitrate in fish tissues were 89~98.7% and 94.1~99.8% for IC, and 98.4~103.7% and 67.7~102.2% for colori-metric method, respectively. Using IC, nitrite was not detected and nitrate was 0.89~1.23mg/kg, while using colorimetric method, nitrite and nitrate were NO~0.08mg/kg and 0.3~0.42mg/kg, respectively. Therefore, the IC method showed better recoveries, and was applicable to extract nitrite and nitrate simultaneously, and is simpler compared with colorimetric method in analyzing nitrite and nitrate from fish tissues.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.4
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• pp.307-313
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• 1995

An automatic method is developed for the determination of SOx in atmosphere. The method involves SOx sampling in diffusion scrubber followed by ion chromatographic analysis. Filtered air is withdrawn at 1.8.ell./min through a diffusion scrubber of which inner tube is made of PTFE(Gore-tex) membrane tubing. 1mM $H_{2}$ $O_{2}$ is used as absorbing solution so that SOx is oxidized to S $O_{4}$$^{2-}$. The scrubbered solution is automatically injected into ion chromatograhpy eith conductivity detection for sulphate determination. Replacement of commonly used polyproplene membrane with PTFE gives several merits such as easy preparation of diffusion scrubber, better collection efficiency. No measurable memory effect is experienced, and this isin contrast to previous work for ammonia. Detection limit of this method defined by three times standard deviation is 0.56ppbv. The precision is 0.4% RSD at SOx concentration of 7.3ppbv Results for Seoulatmosphere ate presented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.147-153
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• 2006

Photocatalyst reaction has limit of its usage because application range mostly centered on atmosphere purification area. Thus, it is true that an alternative plans are necessary to increase usage of $TiO_2$ as photocatalyst material. (1) The result of flow felt according to $TiO_2$ replacement rate has shown that both of anatase type and rutile type over 12% deviated from desired flow, $110{\pm}5mm$. Consequently, the range below 9% will be suitable when the anatase type $TiO_2$ if used for functional additives if workability is considered. (2) After compressive strength test, replacement rate 6-9% is estimated as suitable range if $TiO_2$ is used as compressive strength material. Rutile type and anatase type are suitable for in early-age strength and long-age strength respectively. (3) It was revealed that bending strength was dramatically decreased when replacement rate was increased. The main reason were the increase of $TiO_2$ doesn't influence hydration reaction and the decrease of bending strength. (4) The result from the water purification properties test using ion-chromatograhpy has shown that the condition with anatase type $TiO_2$ was normally better than rutile type on the same replacement rate.