• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.20-28
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• 1992

The x-ray fluorescence(XRF) is one of the most convenient and widely used techniques for analyzing trace elements in ambient particulate matters. The objects of the study were to estimate the optimum exposure time using the XRF, to investigate the distributions of heavy metal levels in particulate matters, and finally to study seasonal variation for the concentrations of total suspended particulate matters(TSP) and size fractionated particulate matters. The suspended particulate matters had been collected by a cascade impactor having 9 size fragnated stages for 3 years(Dec. 1988 to Nov. 1991) in Kyung Hee University-Suwon Campus. The particulate matters were then collected on each stage by membrane filters. The weight concentrations were determined by the XRF system. Thus, seasonal variations and relationship between concentration and particle size could be investigated. Resulting distribution was bimodal with the coarse and the fine particle groups minimum occurring around 2.1 to 3.3 $\mu$m as an aerodynamic diameter. To determine optimum exposure time of the XRF for various trace inorganic elements, membrane filters and the NIST standard filters were extensively studied. Using a statistical technique, optimum exposure time was estimated for each trace element and overall elements. The time was then determined as 20 seconds for the XRF system. The concentration of TSP was 123.9$\mum/m^3$ on an arithmatic average. The levels of each inorganic metal were Si 2420.0ng/$m^3$, Fe 977.1ng/$m^3$, and so on. The Pb. Zn, and Cu abounded in the fine mode group, while Ca, Fe, Si, Al, and K in the coarse group. Marked seasonal variation of TSP and metal concentrations was observed. The concentration of heavy metals in the fine mode was highest in winter : on the other hand, that in the coarse mode was highest in spring.

• Fire Science and Engineering
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• v.26 no.4
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• pp.70-76
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• 2012

This paper deal with vehicle fire caused by damage of diesel particulate filter (DPF) on diesel passenger vehicles. In order to reduce particulate matters included exhaust gases, a DPF in the exhaust system were installed diesel vehicles. A DPF was broken by excessively trapped particulate matters, regeneration error with a malfunction of ECU and defect of suction system such as swirl valve. If the DPF was broken, hot exhaust gases was released to the bottom of vehicle and released hot exhaust gases lead to occur the fire through combustible materials around the exhaust system. When a fire happened in the diesel vehicle caused by damage of DPF, silicate inorganic compounds were attached to the exhaust ventilation pipe and muffler. The silicate inorganic compounds were created by DPF combustion consisting of raw material ceramics. If the silicate inorganic compounds attached to the tail pipe in the diesel passenger vehicles, its fire cause will be assumed damage of DPF.

• Fire Science and Engineering
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• v.5 no.1
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• pp.29-36
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• 1991

The purpose of this study is to understand the variations of the properties of matters according to the heated temperature of inorganic insulation. As a result, form the variation of heat conductivity and maintaining from of insulation, the range of reusable heated temperature of inorganic insulation is as follows. Glass wool : $400^{\circ}C$, Rock wool : $600^{\circ}C$, Perlite : $800^{\circ}C$.

• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.657-662
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• 2012

This study was carried out to evaluate the removal rate of organic and inorganic matters from landfill leachate using pre-treatment process as coagulation and limonite adsorption, and membrane process as RO (reverse osmosis) and NF(nanofiltration). By adding limonite adsorption as pre-treatment process, about 40% of organic matters in leachate was removed through pre-treatment process and 74.7% of boron was removed after RO process without pH adjustment. The rejection rate of boron in RO process mainly depends on the pH and increased at pH value of 10. RO process was performed as two stage system adjusting pH condtion to 7 and 10 in second RO stage for boron removal. Most (>90%) of TOC, Cl- and inorganic matters as Ca was rejected in first RO stage, the residue was rejected in second RO and the rejection rate was above 97%. Considering economic efficiency of operation cost, NF substituted for the first RO and total removal rate of TOC was above 90%. Through RO system toxicity to Daphnia in leachate was removed completely.

• Journal of Korean Society on Water Environment
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• v.21 no.4
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• pp.368-378
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• 2005

Inorganic matters originated from stone quarries and manufacturing plants could alter the ecological characteristics of adjacent aquatic systems, especially the structure and function of benthic macroinvertebrate community. In such situation, the locality of stone quarry and the quantity of inorganic matters would be important factors that determined the disturbing strength to the benthic macroinvertebrate community. Locality patterns of stone quarries were classified into 3 types in relation to the stream ecosystem; stream-proximity, upstream-inclusion and tributary-inclusion type. In the result of species:abundance analysis, stone quarry B (upstream-inclusion type) showed geometric distribution, while others showed broken-stick distribution pattern. The benthic macroinvertebrate communities closer to stone quarries showed smaller species numbers and standing crops among all types of stone quarries. However the values of species evenness index were not seriously different between controls and directly affected sites. These results indicated that the effect of inorganic disturbance would differ from those of organic pollution that induced the highly dominant state occupied by tolerant species. Number of occurred species, standing crops, community indices and biotic indices indicated that the community of upstream-inclusion type was the most seriously damaged from the inorganic disturbance, and the community would be very simple and unstable. Tributary-inclusion stone quarry heavily damaged to tributary system in biologically, but influence to the main stream seemed to be depended on the scale of main stream. Among 3 types of stone quarry localities, stream-proximity type induced the least damages to benthic macroinvertebrate community, though the degrees of damage were different along with distances between stream and stone quarry.

• Ocean and Polar Research
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• v.45 no.3
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• pp.103-111
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• 2023

To evaluate the impact of effluents from land-based fish farms on the coastal ocean of Wando, Korea, we analyzed inorganic nutrients, particulate organic carbon (POC), dissolved organic carbon (DOC), and colored dissolved organic matter (CDOM) in the effluent and influent of land-based fish farms during the summer (July) of 2021. The average concentrations of nutrients (Dissolved inorganic nitrogen, phosphorus, and silicate; DIN, DIP, and DSi, respectively) in the effluents of this study area were 17±3.7 μM, 1.4±0.7 μM, and 14±1.6 μM, respectively. The average concentrations of POC and DOC were 37±22 μM and 81±13 μM, respectively, with POC accounting for about 30% for total organic carbon in effluents. The Reduced Dissolved Inorganic Nitrogen/Total Dissolved Inorganic Nitrogen ratio (0.7), potential short-period index, indicates that the discharge of nutrients excreted by the fish and unconsumed feed into coastal water results in such nutrients being deposited and accumulated in the sediment. Subsequently, this continuous accumulation triggers the release of ammonium ions during organic matter decomposition, and the ammonium-enriched waters that encroach on fish farms as influent seem to be due to the diffusion of high concentrations of ammonium from bottom sediment. Furthermore, we used fluorescence indices to examine the characteristics of organic matter sources, obtaining mean values of 1.54±0.19, 1.06±0.06, and 1.56±0.06 for the humification index, biological index, and fluorescence index, respectively, in the effluent. These results indicate that the organic matters had an autochthonous origin that resulted from microbial decomposition, and such organic matters were rapidly generated and removed by biological activity, likely supplied from the sediment. Our results suggest that the effluent from land-based fish farms could be a potential source of deoxygenation occurrence in coastal areas.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.13-18
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• 1985

Forest soils mixed with organic matters (green needle, flesh needle litter and needle litter in F layer of Pinus koraiensis, and green leaf of Quercus dentata and Q. variabilis) were incubated under a constant $30^{\circ}C({\pm}1)$ for 53 days to measure the changes of inorganic nitrogen and $CO_2$ evolution rate. The results obtained were summarized as follows; 1) In the early incubation period the amounts of total inorganic nitrogen in soils by mixture of organic matters decreased rapidly because of immobilization by microbial uptake, and thereafter their amounts increased with further incubation. 2) The rate of immobilization of organic nitrogen in mixed organic matters was the highest in green needle among green needle, flesh needle litter and needle litter in F layer of P. koraiensis, but lower than that of green leaf of Q. variabilis and Q. dentata. 3) The rates of $CO_2$ evolution from soils mixed with organic matters increased sharply in the early time, and then decreased slowly with increasing time. The order of the $CO_2$ evolution rate was green leaf of Q. variabilis > green leaf of Q. dentata > green needle of P. koraiensis > flesh needle litter of P. koraiensis > needle litter of P. koraiensis in F layer from the largest to the least. 4) Nitrate nitrogen concentrations showed a tendency to increase throughout incubation time, so that their concentrations after 53 days were higher than that of ammonium nitrogen.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.89-102
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• 2000

A total of 318 particulate sample sets consisting of both fine PM(FPM : dp$\leq$2.5 ${\mu}{\textrm}{m}$) and coarse PM(CPM : 2.5${\mu}{\textrm}{m}$${\mu}{\textrm}{m}$) was collected by a dichotomous sampler in Suwon area from December 1996 to November 1997. The concentration of seven inorganic elements such as pb. Cr, Cd, Cu, Zn Fe and Na were determined from each sample using an AAS. The purpose of the study was to extensively investigate environmental behaviors of particulate matters and to provide air quality management schemes applying various statistical approaches. The mean concentrations of PM10 Results of correlation analyses indicated the existence of strong correlations among inorganic elements PM10 FPM CPM and various meterological variables. Our study also examined the degree of uncertainties whether the particular elements can be assorted into the accumulation mode or the coarse mode in their size distribution. Furthermore the analysis of the pollution rose showed graphically the direction of potential sources of particulate matters. According to statistical analyses of our data quantitative differences appeared in the pollution patterns between weekdays and weekends.

• The Korean Journal of Ecology
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• v.28 no.1
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• pp.25-29
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• 2005

This study was carried out to analyze the soil properties of Lepista nuda habitats to form a part of the studies on the characteristics of L. nuda. The soil samples collected from seven studied areas were investigated for soil properties such as soil moisture, soil pH, and the contents of organic and inorganic matters. The content of soil moisture was 29.7% and the content of organic matter was 32.1%. Total nitrogen was 0.74% and soil pH was 4.75, which was ranged from 3.6 to 5.20. In the content of inorganic matter, the content of Fe was highest as 1,024 ppm, K 183 ppm, Mn 21.9 ppm, Ca 2.02 ppm, Zn 1.46 ppm and Mg was lowest as 0.51 ppm.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.117-125
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• 2005

It is common to find lots of organic and inorganic precipitates inside of industrial cooling system. Analytical instruments including ICP-AES, IC, XRD, and SEM were used to investigate the effects of application of Mg on reaction among coolant, precipitates and suspended matters within chiller system. Magnesium (Mg) has a decreasing effect on total dissolved material in the coolant suggesting a significant improvement of quality of coolant. Disappearance of most organic materials in the cooling devices also suggests an inhibitive effect on the growth of organic matters.