• 제목/요약/키워드: chemical concentrations

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공단 인접지역 해송 잎의 무기성분 함량과 산림 토양용액의 화학적 특성간의 관계 (Relationship Between Chemical Properties of Forest soil Solutions and Element concentrations in Needles of Pinus thunbergii in Industral Complexes)

  • 이위영;양재의;박창진;장용선;옥용식
    • 한국토양비료학회지
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    • 제37권5호
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    • pp.322-328
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    • 2004
  • Available nutrients in soil solution play key roles on the growth of plants, but the equilibria in soil solution can be disturbed by acid precipitation. In this study, we investigated the relationships between element concentrations in the needles of Pinus thunbergii and chemical properties of forest soil solutions in the industrial complexes as an effort to find the possible limiting factor(s) causing the forest decline. The Ca/Al molar ratios in needles of Pinus thunbergii collected from the control sites were 18. However, at Onsan and Ulsan industrial complexes, those were decreased to the ranges from 10 to 11 for the one-year old needles and from 9 to 10 for the two-year old needles. The Mg/Al molar ratios showed similar tendencies with the Ca/Al molar ratios of the needles of Pinus thunbergii. In the A horizon, there existed a significant correlation between Mg concentrations in the needles of Pinus thunbergii and Ca/Al molar ratio of forest soil solution. Calcium concentrations in the needles of Pinus thunbergii in the B horizon were also significantly correlated with Ca/Al molar ratios of forest soil solutions. The uptakes of Ca and Mg by Pinus thunbergii were mainly limited by Al in the soil solutions of the A horizon and by Mn and Al in the soil solutions of the B horizon.

양식산 굴(Crassostrea gigas)의 생굴 및 가공소재용으로서 화학적 및 생물학적 위생 특성 (Chemical and Biological Properties on Sanitary of Cultured Oyster Crassostrea gigas Intended for Raw Consumption or Use in Seafood Products)

  • 박선영;이경돈;이정석;허민수;이태기;김진수
    • 한국수산과학회지
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    • 제50권4호
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    • pp.335-342
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    • 2017
  • Oysters Crassostrea gigas are a globally popular shellfish for human consumption. As filter-feeding bivalve mollusks, oysters may harbor many microorganisms and chemicals that could pose potential human health risks. The objective of this study was to investigate the suitability of cultured oysters for raw consumption or use in seafood products by measuring concentrations of harmful microorganisms and chemicals in their flesh. Microbial concentrations in cultured oysters were found to be: $1.0{\times}10^2-6.0{\times}10^4CFU/g$ (viable cell counts), not detected $(ND)-5.4{\times}10^3CFU/g$ (coliform bacteria), $ND-1.3{\times}10^2CFU/g$ (E. coli), and $ND-4.6{\times}10^3CFU/g$ (Vibrio parahaemolyticus). Other pathogenic bacteria, including Enterohemorrhagic E. coli (EHEC), Listeria monocytogenes, Staphylococcus aureus, and Salmonella spp., were not detected in any samples. Heavy metal concentrations of cultured oysters were ND-0.239 mg/kg (total mercury), ND-1.091 mg/kg (lead), ND-0.968 mg/kg (cadmium). The concentrations of benzo(a)pyrene ranged from $0.280-0.880{\mu}g/kg$. Paralytic shellfish poison ranged from ND-0.58 mg/kg, while diarrhetic shellfish poison was not detected. No radioactivity was detected. These results suggest that oysters intended for raw consumption or use in seafood products should be subjected to chemical and biological controls.

Priority Assessment for Remediation of Heavy Metals Closed/Abandoned Mine Areas Using Pollution Indexes

  • 김휘중;양재의;박병길;공성호;이재영;전상호
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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    • pp.183-193
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    • 2006
  • Several metalliferous and coal mines, including Seojin and Okdong located at the Kangwon province, were abandoned or closed since 1989 due to the mining industry promotion policy and thus disposed an enormous amount of mining wastes without a proper treatment facilities, resulting in water and soil pollution in the downstream areas. However, no quantitative assessment was made on soil and water pollution by the transport of mining wastes such as acid mine drainage, mine tailing, and rocky waste. In this research, total and fractional concentrations of heavy metals in mining wastes were analyzed and accordingly the degree of water and soil pollutions in the stream area were quantitatively assessed employing the several pollution indices. Concentrations of Ni, Cd, and Pb in soils near the abandoned coal mine areas were 1,240.0, 25.0 and 1,093.0 mg/kg, respectively, and these concentrations were higher than those in soils near the closed metalliferous mine areas. Also Cu concentrations in soils near the tailing dams were about 1967 mg/kg, which is considered as very polluted level. Results demonstrated that soil at the abandoned mine areas were highly contaminated by AMO, tailing, and effluents of the mining wastes. Therefore, a prompt countermeasure on the mining waste treatment and remediation of the codntaminated water and soil should be made to the abandoned or closed metalliferous and coal mines located at the abandoned mine area.

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ABC-EAREX2005 미세 에어러솔의 화학적 특성 (Chemical Characteristics of Fine Aerosols During ABC-EAREX2005)

  • 송미정;이미혜;문광주;한진석;김경렬;이강웅
    • 한국대기환경학회지
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    • 제22권5호
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    • pp.604-613
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    • 2006
  • The chemical composition of $PM_{2.5}$ such as ${SO_4}^{2-},\;{NO_3}^-,\;Cl^-,\;{NH_4}^+,\;Ca^{2+},\;K^+,\;Na^+,\;Mg^{2+}$, OC, and EC and the concentrations of reactive trace gases including $O_3,\;CO,\;NOx,\;SO_2,\;and\;H_2O_2$ were measured at Gosan in Jeju Island during March $13{\sim}30$, as a part of the Atmospheric Brown Clouds-East Asian Regional Experiment 2005(ABC-EAREX2005). The average mass concentrations of $PM_{2.5}$ was 27.3 ${\mu}g/m^3$, of which OC showed the highest concentration as 4.22 ${\mu}g/m^3$ and nss ${SO_4}^{2-}$ was the second highest as 3.34 ${\mu}g/m^3$. During that period, average concentrations of CO and $O_3$ was about 300 ppbv and 56 ppbv, respectively. For the whole experiment, the correlations of CO with ${SO_4}^{2-}$ and EC were very good, which suggests that CO can be used as tracer for the formation of fine aerosols. Several pollution and dust episodes were identified by the enhancement of CO, OC, EC, nss ${SO_4}^{2-},\;or\;Ca^{2+}$ concentrations or their ratios. In conjunction with factor analysis, air trajectory analysis, and comparison with emission inventories, these results indicate the spring aerosols collected at Gosan was strongly influenced by Asian outflows.

중금속, 암모니아, 유기주석화합물이 피조개 (Scapharca broughtonii) 의 생존에 미치는 영향 (Influence of Heavy Metals, Ammonia, and Organotin Compounds on the Survival of Arkshell Clams, Scapharca broughtonii)

  • 김찬국;김동훈;이정석;이규태
    • 한국패류학회지
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    • 제20권1호
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    • pp.93-105
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    • 2004
  • Arkshell clams, Scapharca broughtonii, are economically important edible bivalves and widely cultivated in the Southern coast of Korea. Recently, the production of S. broughtonii has been dramatically decreased and various reasons including chemical pollution were suspected to be related to the production declines. However, it remains unknown whether the chemical pollution levels of the surrounding environments were high enough for the biological and ecological disturbance for the population of S. broughtonii, because no systematic toxicological study using S. broughtonii has been conducted previously. In the present study, we exposed arkshell clams, S. broughtonii to various waterborne pollutants including heavy metals (Cd, Cu and Hg), ammonia and organotins (tributyltin and triphenyltin) to determine the effect concentrations of these pollutants for the survival of S. broughtonii for 20 days. The median lethal concentrations ($LC_50$) of S. broughtonii were 2.1 mg/l for Cd, 0.065 mg/l for Cu, 0.40 mg/l for Hg, 79.4 mg/l for total ammonia (1.9 mg/l for unionized ammonia), 0.5 ${\mu}$g/l for TBT, and 14${\mu}$g/l for TPhT. Lethal toxicity of the most pollutants increased with both exposure duration and concentration. The toxicity of TBT was greatest for S. broughtonii, followed by TPhT > Cu > Hg > Cd > ammonia. The sensitivities of S. broughtonii to heavy metals and TBT were comparable to those of other aquatic organisms, but they were relatively tolerable to ammonia. The environmental concentrations of the tested pollutants were compared with the effect concentrations of those for the survival of S. broughtonii to assess the potential risks of the pollutants in the field conditions.

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개에서 신장결석의 제거를 위한 신절개술 (Removal of Renal Calculi by Nephrotomy in Two Dogs)

  • 정순욱;김진영;최치봉;이경리;최혜정;김지헌;정병현
    • 한국임상수의학회지
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    • 제17권2호
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    • pp.480-484
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    • 2000
  • A 10 years old female Poodle weighing 4.38 kg and a 10 years old female Maltese weighing 4.33kg were referred to veterinary leaching hospital of college of veterinary medicine, Konkuk uni-versity because of hematuria and severa anorexia. Preoperative hematological and srum chemical values revealed that counts of WBC were $78.4{\times}10^3$,/TEX>/ul in the Poodle and $21.6{\times}10^3$in the Maltese, concentrations of BUN 105 and 13 mg/dl, concentrations of creatinine 4.0 and 1.4 mg/dl, concentration of ALKP 542 U/L in the Poodle and concentration of ALF 37 U/L in the Maltese, respectively. Radiographic findings were observed radiopaque bilateral nephroliths in the Poodle and right renal cal- culus in the Maltese. Ultrasonographic findings were showed hyperechoic mass with severe acoustic shadowing, which were ]ocated in the center of both kidneys parenchyma in the Poodle and in right kidney in the Maltese. Bisectional nephrotomy in right kidney for removal of calculus, which had ,sin- gle stone and more large than splitted stones in lets kidney in the Poodle, was performed under isnf- lurane anesthesia in 100% $O_2$. The time from temporary occlusion of blood flow to suture of incisioned kidney after removal of renal calculi was elapsed 12 minutes. During operation and until 24hrs after operation was infusioned mannitol and tranexanic acid solution. There were normal urination with yellow color in the Poodle at 3 days after operation and in the Maltese at 1 day and good appetite after 7 days and 1 day after operation. At 7 days and 9 days after operation, hematolgoical and seam chemical values repealed that counts of WBC were $29.8{\times}10^3/u1 in the Poodle and 13.1 {\itmes}10^3$/ul in the Mal- tese, concentrations of BUN 13 and 10 mg/dl. concentrations of creatinine 1.3 and 1.1 mg/dl, con-centrations of ALT 34 and 97U/L, concentraion of AST 10 U/L in the Poodle, respectively, By ultra-sonographic view there was not observed hyperechoic mass and radippaque calculus in operated kid-ney in radiographic view.

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Background Level of Atmospheric Radon-222 Concentrations at Gosan Station, Jeju Island, Korea in 2011

  • Kim, Won-Hyung;Ko, Hee-Jung;Hu, Chul-Goo;Lee, Haeyoung;Lee, Chulkyu;Chambers, S.;Williams, A.G.;Kang, Chang-Hee
    • Bulletin of the Korean Chemical Society
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    • 제35권4호
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    • pp.1149-1153
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    • 2014
  • Real-time monitoring of hourly atmospheric radon (Rn-222) concentration was performed throughout 2011 at Gosan station, Jeju Island, one of the least polluted regions in Korea, in order to characterize the background levels, and temporal variations on diurnal to seasonal time-scales. The annual mean radon concentration for 2011 was $2527{\pm}1356$ mBq $m^{-3}$, and the seasonal cycle was characterized by a broad winter maximum, and narrow summer minimum. Mean monthly radon concentrations, in descending order of magnitude, were Oct > Sep > Feb > Nov > Jan > Dec > Mar > Aug > Apr > Jun > May > Jul. The maximum monthly mean value (3595 mBq $m^{-3}$, October), exceeded the minimum value (1243 mBq $m^{-3}$, July), by almost a factor of three. Diurnal composite hourly concentrations increased throughout the night to reach their maximum (2956 mBq $m^{-3}$) at around 7 a.m., after which they decreased to their minimum value (2259 mBq $m^{-3}$) at around 3 p.m. Back trajectory analyses indicated that the highest radon events typically exhibited long-term continental fetch over Asia before arriving at Jeju. In contrast, low radon events were generally correlated with air mass fetch over the North Pacific Ocean. Radon concentrations typical of predominantly continental, and predominantly oceanic fetch, differed by a factor of 3.8.

Measurement Uncertainty of Nicotine in Environmental Tobacco Smoke (ETS)

  • Lee, Jeong-Il;Lee, Cheol Min;Shim, In-Keun;Kim, Seong-Mi;Lee, Woo-Seok;Kim, Yoon-Shin
    • Bulletin of the Korean Chemical Society
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    • 제34권8호
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    • pp.2394-2398
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    • 2013
  • Nicotine is the main component of environmental tobacco smoke, and its presence in indoor air is widely used as a secondhand-smoke indicator. Environmental tobacco smoke is a major source of indoor air pollution, but sufficient investigation of the uncertainty of its measurement, which mirrors the reliability of nicotine measurement, has not been performed. We calculated the uncertainty of measurement of indoor air nicotine concentration at low, medium, and high concentrations of 11.3798, 10.1977, $98.3768{\mu}g/m^3$, respectively, and we employed the Guide to the Expression of Uncertainty in Measurements (GUM), proposed by the International Organization for Standardization (ISO). The factors considered in determining the uncertainty were uncertainty of the calibration curve (calibration curve and repeated measurements), desorption efficiency, extraction volume, and sampling airflow (accuracy and acceptable limits of flowmeter). The measurement uncertainty was highest at low concentrations; the expanded measurement uncertainty is $0.9435{\mu}g/m^3$ and is represented as a relative uncertainty of 63.38%. At medium and high (concentrations, the relative uncertainty was 13.1% and 9.1%, respectively. The uncertainty of the calibration curve was largest for low indoor nicotine concentrations. To increase reliability of measurement in assessing the effect of secondhand smoke, measures such as increasing the sample injection rate ($1{\mu}L$ or more), increasing sampling volume to increase collected nicotine, and using gas chromatography-mass spectrometry (GC/MS) or GC/MS/MS, which has a lower quantitation threshold, rather than gas chromatography with nitrogen phosphorous detector, should be considered.

Physical and Chemical Management Practices for Improving Water Quality in Channel Catfish Ictalurus punctatus Aquaculture

  • Seo, Jin-Won
    • 한국양식학회지
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    • 제15권1호
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    • pp.49-60
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    • 2002
  • Research on practices for improving water quality in channel catfish Ictalurus punctatus ponds was conducted at the Auburn University Fisheries Research Station, Auburn, Alabama, in 1998 and 1999. The objective of this two-year study was to determine better management practices to enhance water quality and improve production efficiency. In the first year, oxidation of bottom soil by drying, tilling, and applying sodium nitrate was performed (dry-till and dry-till with sodium nitrate treatments). The second year, based on the results obtained during the first year, precipitation of phosphorus (P) from water by applying gypsum was compared to the dry-till treatment (dry-till and dry-till with gypsum treatments). Control ponds were not subjected to bottom drying, tilling, sodium nitrate, or gypsum treatment. Channel catfish fingerings were stocked at 15,000/ha. In the first year, water in ponds from dry-till and dry-till with sodium nitrate treatments had lower concentrations (P < 0.01) of soluble reactive P, nitrate ($NO_{3} ^{-}) and nitrite ($NO_{2} ^{-}) nitrogen (N), total ammonia ($NH_3$) nitrogen, total suspended solids and turbidity, and higher values of pH, Secchi disk visibility, total alkalinity, total hardness, and calcium ($Ca^{2+}) hardness than water in control ponds. Ponds of the dry-till treatment also had lower concentrations (P < 0.01) of total P and total N than control ponds. Total fish production and survival rate did not differ among the treatments (P > 0.05). The findings suggested that drying and tiling pond bosoms between crops could achieve water quality improvement. Applying sodium nitrate to dry, tilled pond bosoms did not provide water quality improvement. In the second year, the treatment with the best results from the first year, dry-till, was compared with a dry-till with gypsum treatment. Enough gypsum was applied to give a total hardness of about 200 mg/L, and gypsum was reapplied as needed to maintain the hardness. Compared to the control, dry-till and dry-till with gypsum treatments had lower concentrations (P < 0.01) of total and soluble reactive P, total N, and total $NH_3$-N, and higher concentrations (P < 0.01) of dissolved oxygen. Ponds of the duty-till with gypsum treatment also had lower concentrations (P < 0.01) of chlorophyll $\alpha$, chemical oxygen demand, and total alkalinity than the control. Total fish production and survival rate did not differ (P > 0.05) among the treatments. These findings suggest that drying and tilling pond bosoms between crops and treating low hardness waters with gypsum could achieve water Quality improvement.

Relationship between Selected Metal Concentrations in Korean Raspberry (Rubus coreanus) Plant and Different Chemical Fractions of the Metals in Soil

  • Ahn, Byung-Koo;Lee, Jang-Choon;Han, Soo-Gon;Lee, Jin-Ho
    • 한국토양비료학회지
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    • 제44권4호
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    • pp.591-596
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    • 2011
  • The applications of chemical fertilizers and various types of organic materials may cause heavy metal accumulation in soil. In this study, we conducted to investigate the relationship between the different chemical forms of heavy metals such as Cr, Cd, Pb, Cu, Ni, and Zn retained in soil and the metal concentrations in Korean raspberry plant. Forty five soil samples were collected from 2 to 6 years old Korean raspberry cultivation fields (RCFs), Gochang, Korea, to determine total, exchangeable (1.0 M $MgCl_2$-extractable), DTPA-extractable metal contents. The leaves and fruits of raspberry plant were sampled at harvest stage. Total metal contents in soils ranged from $0.87mg\;kg^{-1}$ to $66.82mg\;kg^{-1}$. Exchangeable and DTPA-extractable metals ranged between 0.02 and $0.67mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $7.07mg\;kg^{-1}$, respectively. The metal concentrations in the plant leaf and fruit determined on a dry-basis were between $1.30mg\;kg^{-1}$ and $38.82mg\;kg^{-1}$ and between $0.05mg\;kg^{-1}$ and $21.51mg\;kg^{-1}$, respectively, but Cd and Pb were not detected in the leaf. The total, exchangeable, and DTPA-extractable contents of the metal ions in soil were directly correlated one another, but the contents of different metals in the different fractions were inversely correlated in general. Most of total and DTPA-extractable metals in the soil were directly correlated with the contents of the same metals in the plant, whereas exchangeable metals in the soil were not statistically correlated with the same metals in plants. Thus, we concluded that the metal contents in the raspberry field soils were much lower thanthe levels of Soil Contamination Warning Standard (SCWS), and the plant metal concentrations were also less than the maximum permissible limits. The total and DTPA-extractable metals in the soil were closely related to the metal concentrations in the plant.