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Matrix effect on the Determination of Inorganic Priority Pollutants in Sludges (오니 시료중의 무기 Priority Pollutants의 분석 과정에 미치는 매질의 영향)

  • Lee, Huk-Hee;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.11 no.4
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    • pp.297-304
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    • 1998
  • The three analysis methods, EPA method 3050, the method offered by Ministry of Environment in Korea, and modified method corrected in this laboratory, were studied to investigate the effect of matrix on the analysis of inorganic priority pollutants. 7 inorganic priority pollutants(Ni, Cr, Cu, Zn, Pb, Cd, Hg) were spiked to the plating, leather, paper, electric, and dye sludges. Mean recovery of the elements except Hg was 95.5% when the procedure of EPA method was applied. However, recovery by the two other extraction methods showed 11.1% and 27.7%, respectively. Digestions were done by MDS (microwave digestion system) and $HNO_3+HClO_4$ methods. To study organic and inorganic matrix effect, samples were made by adding triethanol amine as a organic matrix and $FeCl_3{\cdot}6H_2O$+$AlCl_3{\cdot}6H_2O$ as a inorganic matrix, respectively. The extracts were analyzed by AAS and HG-AAS. Mean recovery of the elements by the $HNO_3+HClO_4$ procedure, except Hg, gave better result than that of the MDS method. Mean recovery of elements was decreased when organic and inorganic matrices were added in the sludge samples. The procedure of MDS and $HNO_3+HClO_4$ digestion gave higher recoveries than that of direct analysis. In general, the results of the studies showed a significant matrix effect on the inorganic priority pollutants analysis in sludges.

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Removal Characteristics of Heavy Metals in Acid Wastewater by Ceramics Using Natural Zeolite and Converter Slag (천연제올라이트와 제강전로슬래그를 이용한 세라믹 소재에 의한 산성폐수 내 중금속의 제거특성)

  • Kim, Dong-Hee;Yim, Soo-Bin
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.4
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    • pp.239-246
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    • 2012
  • This study was performed to investigate the removal characteristics and mechanism of heavy metals using pellet-type ceramics(ZS ceramics), in which natural zeolite was mixed and calcined with converter slag. The optimal calcination temperature range was measured to be $600{\sim}800^{\circ}C$. The calcination time had little effect on the removal of heavy metal in acid wastewater. The adequate dose of ceramics was shown to be 2~5% for removal of heavy metals in acid wastewater. The maximum removal capacity of ZS ceramics for heavy metals were observed to be Al 84.7 mg/g, Cd 37.3 mg/g, Cr 81.7 mg/g, Cu 55.6 mg/g, Fe 57.2 mg/g, Mn 32.1 mg/g, Ni 38.0 mg/g, Pb 71.6 mg/g, Zn 46.3 mg/g. The pH played a pivotal role in the removal of heavy metals by ZS ceramics. The analysis results of mechanism exhibited that the ZS ceramics could act as a multi-functional ceramics for removal of heavy metals in acid wastewater by adsorption, ion-exchange, or precipitation.

Indoor Air Quality Pollution of PM2.5 and Associated Trace Elements Affected by Environmental Tobacco Smoke (환경담배연기로 인한 실내공기 중 PM2.5 및 미량성분 오염 특성)

  • Lim, Jong-Myoung;Lee, Jin-Hong
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.5
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    • pp.317-324
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    • 2014
  • Environmental tobacco smoke (ETS) samples were collected separately in mainstream and side-stream smoke using a self-designed smoking machine, and a total 40 of PM2.5 was collected with low volume air sampler at indoor environments with and without ETS in Daejeon, Korea. About 20 trace elements including toxic metals like As, Cr, Mn, Se, V, and Zn were determined in PM2.5 and ETS samples by instrumental neutron activation analysis (INAA). It is found that the emission factors of K, Cl, Na, and Al were much higher than those of toxic elements for both mainstream and side-stream smoke. The average concentration of PM2.5 was enriched by 1.5 times at smoking area ($58.7{\pm}18.1{\mu}g/m^3$) than at smoking free area ($38.6{\pm}12.7{\mu}g/m^3$). The concentration ratio of each element between smoking and smoking free area were ranged from 1.1 to 6.0 except Cu (1.0); especially, Ce (6.0), La (5.2), K (2.3), and Co (2.0) showed higher ratio, which suggests that the ETS is one of the possible increasing factors of PM2.5 and elemental concentration at indoor environment.

Hypoglycemic Effects of Korean Wild Vegetables (한국산 야생식용물의 혈당강하효과)

  • Sook Ja Lim
    • Journal of Nutrition and Health
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    • v.25 no.6
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    • pp.511-517
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    • 1992
  • The hypoglycemic effects of Korean wild vegetables : Capsella bursa-pastoris Medicus(CBM) Commelina communis L. (CCL) Calystegics japonica Choisy(CJC) Discorea japonica Thunb(DJT) and Persicaria perfolidata Gross(PPG) in diabetic rats were determined. Sixty male Sprague-Dawley diabetic rats(130~180g) induced by the streptozotocin (45mg/kg) injection into the tail vein were fed either a control or experimental diets for four weeks. The plasma levels of glucose and cholesterol were measured. The urinary glucose levels were monitored. Crude fiber mineral(Ca, Fe, Zn and Cr) and ascorbic acid contents of the wild vegetables were analyzed. The extents of blood glucose decrement in CCL. DJT or PPG fed rats were greater than that in the control group. This extents of decrement in CBM or CJC fed rats were not significan-tly different from that in the control group. The urinary glucose was shown to be negative to Band reagent strip in CCL or DJT group at the 4th week. The plasma cholesterol levels of all the groups including control group were not essentially different. It is suggested that the intakes of CCL or DJT could be useful for prevetive and therapeutic approches to alleviate the hyperglycemic status in diabetes mellitus.

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An Experimental Research on Uniform Corrosion of Inconel 600 and 690 Tubing Material (Inconel 600 및 690 튜브 재질의 일반 부식에 관한 실험적 연구)

  • Yeom Yu-Sun;Hwang Jung-Lae;Jun In-Sub;Kim Soong-Pyung;Yoon Jang-Hee
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.4 no.2
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    • pp.103-116
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    • 2006
  • By executing corrosion experiment on Inconel 600, 690 used to material of S/G tube in domestic NPP, this paper show estimation of amount of product such as Co-58, Co-60, Cr-51, Mn-54, Fe-59 which are main exposure cause to the workers in NPP. Therefore, Making the 12 samples consisted of Inconel 600, 690, whole corrosion experiment was carried out for 60 days(each pH by 20 days). The conditions of those tests were similar or more harsh than actual conditions of domestic NPP. The Glow Discharge Spectrometer(GDS) was used for quantitative analysis of results. The results of using GDS, the Inconel 600 corrodes more than Inconel 690 at pH 7 and pH 9. However, it is observed that Inconel 690 corrodes more than Inconel 600 at pH 4. Those results is estimated that test sections had the effect of transient. The long terms of experiment is required to minimize and solve the problem.

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Characteristics of Trace Element Concentrations in Dust by Facilities and Areas in Daegu, Korea (대구지역 축적먼지 중 미량원소성분의 시설별 및 지역별 농도분포)

  • Song, Hee-Bong;Do, Hwa-Seok;Kwak, Jin-Hee;Kim, Jong-Woo;Kang, Jae-Hyoung;Phee, Young-Gyu
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.3
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    • pp.287-295
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    • 2010
  • Dust samples have been collected from streets, schools, subway stations and households in Daegu metropolitan city. Samples were sieved through a 100 ${\mu}m$ mesh and the concentration of 14 elements have been determined using by ICP after acid extraction. Results showed that Ca, Fe, K, Mg, Mn, Na and V were influenced by natural sources while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources. The measured values were remarkably higher in components from natural sources than in components from anthropogenic sources. In particular, school dust had higher levels of Ca and Pb and subway station dust had higher levels of Cu and Zn. The percentage composition of chemicals from subway stations, households, and schools were remarkably higher in components from anthropogenic sources than that from streets. It is well recognized that anthropogenic sources were affected by indoor dust. Results of pollution index of hazardous heavy metals indicated that schools, households, and subway stations were more contaminated than streets and urban areas typically had higher pollution index than rural areas. The correlation analysis among trace elements seem to suggest that there were correlations between components of soil/road dust resuspension, and components of waste incineration and fuel combustion.

The controversial points and a remedy on evaluation of heavy metal contamination in standard method for examination of soil in Korea. (국내 토양오염 공정시험방법중 중금속 관련 오염평가의 문제점과 개선책)

  • 오창환;유연희;이평구;박성원;이영엽
    • Journal of Soil and Groundwater Environment
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    • v.6 no.1
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    • pp.63-83
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    • 2001
  • Heavy metals are extracted from stream sediments, roadside soils and sediments and soils and tailings from mining area using partial extraction, acid digestion and HF-digestion. Compared to amounts of heavy metals extracted using partial extraction, those extracted using acid digestion are higher by 2.0∼221 times in Cu, 2.4∼2806 times in Pb, 1.3∼121 times in Cd, 14. 1∼1300885 times in Fe, 1.2∼272 times in Mn, 1.3∼373 times in Zn, 2.2∼1735 times in Cr. There is no special relationship between the extracted amounts of heavy metals using partial extraction and those using acid digestion. However, it is possible that there is a certain relationship between those using acid digestion and those using HF-digestion. Although partial extraction, which extracts less amounts of heavy metals (Cd, Cu, Pb) from soil compared to acid digestion, is used in domestic standard method for examination of soil, domestic soil standard for heavy metals in non-agricultural and industrial areas is higher than soil standard in foreign countries which use acid digestion. For improvement of the domestic standard method for assessment of soil, it is suggested to lower the domestic soil standard for heavy metals or to change pretreatment method for extracting heavy metals from partial extraction to acid digestion with modifying the soil standard.

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Applied Mineralogy for the Conservation of Dinosaur Tracks in the Goseong Interchange Area (35번 고속도로 고성 교차로 지역 공룡발자국의 보존을 위한 응용광물학적 연구)

  • Jeong Gi Young;Kim Soo Jin
    • Journal of the Mineralogical Society of Korea
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    • v.17 no.3
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    • pp.189-199
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    • 2004
  • Cretaceous sedimentary rocks bearing dinosaur tracks in the Goseong interchange area were studied for their conservation and public display in the aspect of applied mineralogy. Black clay layers alternate with silt layers in the sedimentary rocks. The verical and horizontal fissures are commonly filled with calcite veinlets, supergenetic iron and manganese oxides. The rocks are composed of quartz, albite, K-feldspar, calcite, chlorite, illite, muscovite, and biotite, with minor apatite and rutile. Silt layers are relatively rich in calcite and albite, whereas clay layers are abundant in quartz, illite, and chlorite. Al, Fe, Mg, K, Ti, and P are enriched in the clay layers, while Ca, Na, and Mn in silt. Most of trace elements including V, Cr, Co, Ni, Cs, Zr, REE, Th, and U are enriched in clay layers. Inorganic carbon are present in silt layers as calcite, while organic carbon in black clay layers. The black clay layers were partly altered to yellow clay layers along the fissures, simultaneously with the decrease of organic carbon. Selective exfoliation of clay-rich black and yellow clay layers, calcite matrix of silt layers and calcite infillings of fissures are estimated as the major weakness potentially promoting chemical and physical degradation of the track-bearing rock specimens.

Effect of Soil Properties on Leaching of Preservative Components from CCA-treated Wood (토양 특성이 CCA 처리재로부터 방부제 성분의 용탈에 미치는 영향)

  • Jeong, Yong Gi;Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.6 s.134
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    • pp.87-94
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    • 2005
  • This study was carried out to investigate the effect of soil types and soil properties on wood preservative leaching. Radiata pine (Pinus radiata Don.) sapwood stakes, which had been treated with 2.0%(w/v) CCA, were leached for 12 weeks by a common laboratory method in four different soils and for 14 days by the AWPA standard leaching method in water. The physical and chemical properties of the four soils were determined, and the percent leaching of the individual component of CCA was correlated with the various soil properties. The data show that leaching of preservative chemicals from treated wood exposed to soil is influenced by the type of soil. The preservative leaching was greater when wood was exposed to water than when the wood was in contact with water-saturated soil. The greatest chromium, copper and arsenic leaching from CCA-treated stakes were observed in the sandy loam, loam, and sand, respectively, and the least amount of leaching of CCA components occurred in the silty loam. The leaching of preservative components from treated wood is extremely complex and appears to be influenced differently by the soil properties. The extent of copper leaching from CCA treated wood appears to be related to exchangeable Mg and sum of bases. There is a reasonably good relationship between chromium leaching and exchangeable Mg, and between arsenic leaching and exchangeable K, soil Ni, Mn, Fe, Cr, or Cu content. Since this study was conducted based on laboratory leaching method using small cross-sectional dimensions; thus, data obtained from this experiment should not be used to predict leaching characteristics from commercial-size wood used in real situation. Accordingly, further studies are necessary using outdoor ground-contact leaching.

Current Researches on the Protection of Exterior Wood from Weathering (목재의 기상열화 방지에 관한 최근의 연구 동향)

  • Kim, Yeong-Suk
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.5
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    • pp.449-470
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    • 2018
  • A review of research trends on wood surface protection for exterior use obtained the following conclusions: It has been reported that inorganic compounds such as chrome and copper used as wood preservatives can protect wood from weathering. It has been shown that precoating with hydrophobic substances such as wax and oil, UV absorbers, and HALS (Hindered Amine Light Stabilizers) enhances weathering resistance on the surface of ACQ-treated wood. Opaque coatings of paint/stains and semitransparent stains on the surface of preservative treated wood can increase the synergistic effects on prevention of weathering deterioration. Also the need for repainting periodically for the protection of the preservative treated wood surface has also been suggested. ZnO or $TiO_2$ of fine particles, metal ions such as Co, Cr, Fe, Mn, Ni and Ti, and UV absorbers such as tris-resorcinol triazine derivatives, triazine and benzotriazole were introduced as additives for preventing UV in the transparent coating on wood. Several reports showed that chemical modification such as methylation, acetylation, or alkylations have made some increases the effects of preventing weathering with the increasing weight gain of chemical formulas. In heat-treated wood, there were various contradictory reports on the resistance of weathering, and there were some other reports emphasizing the necessity of painting with UV resistance, which leads to the necessity of more advanced studies.