• Title/Summary/Keyword: lead (Pb)

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Heavy metals and pollution index of agricultural soils around industrial complexes in the Jeon-Buk regions of Korea

  • Suwanmanon, Sorakon;Kim, Ki In
    • Korean Journal of Agricultural Science
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    • v.46 no.4
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    • pp.799-811
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    • 2019
  • The aim of this study was to evaluate heavy metal contamination and pollution index of agricultural soils around industrial complexes in the Jeon-Buk Regions of Korea. Soil samples near industrial complexes in 2017 were collected at two depths (0 - 15 and 15 - 30 cm) within a 500- and 1000-meter radius before planting. Eight heavy metals (Arsenic (As), cadmium (Cd), chromium (Cr), Cupper (Cu), nickel (Ni), lead (Pb), mercury (Hg) and zinc (Zn)) and the pollution index (PI), geoaccumulation index (Igeo) and soil pollution index (SPI) were evaluated based on soil contamination warning standard (SCWS). Overall, the heavy metal concentrations were below the SCWS. The PI ranged from 0.1 to 0.9 and categorized into Group 1 which is not polluted with any heavy metals. The average Igeo values of all the soil samples ranged from - 2.56 to 3.22. The Igeo values of Cd and Hg may not represent well the pollution index because the heavy metal concentrations in the soil is lower compared to the SCWS. In fact, based on the heavy metal concentrations, the Igeo for monitored soils should be categorized into Group 1, uncontaminated to moderately contaminated. However, the Igeo of Cd and Hg are classified into heavily contaminated. These results suggest that for calculating the Igeo, the heavy metal concentration and background concentration should be used very carefully if the heavy metal concentration in the soil is lower than the background concentration. SPI for all the soil samples ranged from 0.00 to 0.11 which indicates no heavy metal pollution was observed.

The Correlation of Heavy Metal Contents in Herbal Medicines and Their Soils at North Gyeongbuk Area (경북북부지역 한약재와 재배토양중의 중금속과의 상관관계)

  • Park Moon-Ki;Lee Hyeun-Jeung;Kim Kwang-Joong;Moon Young-Soo
    • Journal of Environmental Science International
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    • v.14 no.2
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    • pp.185-192
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    • 2005
  • The concentration of heavy metal were studied for the estimation of quality in herbal medicines which is Bupleuri Radix, Paeoniae Radix, Dioscoreae Rhizoma and Astragali Radix in products of north Gyeongbuk area Also, we collected soils from several area in Gyeongbuk, and determined heavy metal concentration of soils by ICP. We compared with herbal medicines in products of Gyeongbuk and their soils. The average levels of heavy metal of herbal medicines in Gyeongbuk area are as follows: Mercury is 0.037mg/kg, Chromium is 0.093 mg/kg, Nickel is 0.108mg/kg, Copper is 0.475mg/kg, Zinc is 3.14mg/kg, Manganese is 1.52mg/kg, Iron is 7,83mg/kg, and Cadmium, Lead and Arsenic is not detected. It was very lower in concentrations than those of average Korea area. For the heavy metals contents of Gyeongbuk area, in Gong Jung Ri, represented the higher level, it may be due to a near the road. The Cd contents in soil was not a wide difference. For the As and Pb contents in soil, Song Sa Ri (Bupleuri Radix) represented the higher level(0.68mg/kg, 1523mg/kg). Correlation coefficients of heavy metal contents in cultured herbal medicines and their soils did not give reproducible results. But the degree of correlation between a few heavy metal contents of Dioscoreae Rhizoma and their soil showed the good transfer from the soil.

The Piezoelectric Properties of (Na0.5K0.5)NbO3-K4CuNb8O23 Ceramics with Various K4CuNb8O23 Doping and Sintering Temperatures

  • Yoon, Jung-Rag;Lee, Chang-Bae;Lee, Kyung-Min;Lee, Heun-Young;Lee, Serk-Won
    • Transactions on Electrical and Electronic Materials
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    • v.11 no.3
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    • pp.126-129
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    • 2010
  • (1-X) $(Na_{0.5}K_{0.5})NbO_3-X$ $K_4CuNb_8O_{23}$ (NKN-X KCN) ceramics were produced using the conventional solid state sintering method, and their sinterability and electric properties were investigated. The density, dielectric constant (${\varepsilon}_r$), piezoelectric constant $d_{33}$, electromechanical coupling factor $k_p$ and mechanical quality factor $Q_m$ value of the NKN ceramics depended upon the KCN content and the sintering temperature. In particular, the KCN addition to the NKN greatly improved the mechanical quality factor $Q_m$ value. The ceramic with X = 2.0 mol% sintered at $1,150^{\circ}C$ possesses the optimum properties (${\varepsilon}_r=241$, $d_{33}=78$, $k_p=0.34$ and $Q_m=1,121$). These results indicate that the ceramic is a promising candidate material for applications in lead free piezoelectric transformer and filter materials.

Evaluation of Microstructure and Electrical Properties in (Na,K)NbO3-Based Pb-free Piezoelectrics Doped with Various Cu2O Concentration ((Na,K)NbO3계 무연 압전체에서 Cu2O 첨가물의 농도 변화에 따른 미세구조 및 전기적 특성 평가)

  • Lee, Youn-Ki;Ryu, Sung-Lim;Kweon, Soon-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.11
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    • pp.870-875
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    • 2011
  • The $(Na_{0.52}K_{0.44})(Nb_{0.9}Sb_{0.06})O_3-0.04dLiTaO_3$ (NKNS-LT) ceramics with various $Cu_2O$ concentration were prepared by the conventional solid state reaction method. The $Cu_2O$ content was varied in the range of 0.1~0.4 wt%. The effects of Cu on microstructure, crystallographic phase transition, and piezoelectric properties were investigated. The material with perovskite structure had a tetragonal phase (T1) when $Cu_2O$ concentration was less than 0.3 wt% and it transformed to another tetragonal phase (T2) when the $Cu_2O$ amount was greater than 0.3 wt%. The phase boundary between T1 and T2 phases appeared at around 0.3 wt% of $Cu_2O$ concentration. The piezoelectric properties were shown the maximum values at the composition of the phase boundary. The electro-mechanical coupling factor ($k_p$) was 0.42 and the piezoelectric charge constant ($d_{33}$) was 245 pC/N at the 0.3 wt% of $Cu_2O$ concentration.

External Quality Assessment Scheme for Biological Monitoring of Occupational Exposure to Toxic Chemicals

  • Lee, Mi-Young;Yang, Jeong-Sun;Kang, Seong-Kyu
    • Safety and Health at Work
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    • v.2 no.3
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    • pp.229-235
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    • 2011
  • Objectives: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a $31^{st}$ round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. Methods: One hundred and eighteen laboratories participated in the $31^{st}$ round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. Results: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. Conclusion: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.

A Study on Removal Efficiency and Applicability of Natural Type Road Non-point Pollutant Reduction Facilities (자연형 도로 비점오염저감시설의 저감효율 및 적용성 연구)

  • Lee, Sang Hyuk;Cho, Hye Jin;Kim, Lee Hyung
    • International Journal of Highway Engineering
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    • v.16 no.6
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    • pp.9-17
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    • 2014
  • PURPOSES : The purpose of this study is to assess removal efficiency of non-point pollutants and applicability for non-point pollutant reduction facilities by conducting the demonstration project operation. METHODS : In order to analyze removal efficiency of non-point pollutants for facilities such as a grassed swale, a small constructed wetland, a free water surface wetland, a horizontal sub-surface flow wetland, and a sand filtration, the field data including specifications of facilities, rainfall, inflow and runoff rainfall effluent etc. was acquired after occurring rainfall events, and the acquired data was analyzed for removal efficiency rate to assess road non-point pollutants facilities using event mean concentration (EMC) and summation of load (SOL) methods. RESULTS : The results of analyzing rainfall effluent, non-point pollutant sources showed that total suspended solid (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), chrome (Cr), zinc (Zn), and lead (Pb) can be removed through non-point pollutant reduction facilities by 60.3% ~ 100%. Especially removal efficiency of TSS, COD and BOD is relatively higher than removal efficiency of other non-point pollutant sources in all kind of non-point pollutant facilities. CONCLUSIONS : Based on the result of this study, even though natural type of non-point pollutant reduction facilities for roads occupy small areas comparing with drainage basin areas, most of non-point pollutant sources would be removed through the facilities.

The Contents Of Heavy Metals In Sediments From The Southeastern Coastal Area Of Korea (한국 남해동부연안 해저퇴적물중의 중금속 함량에 관한 연구)

  • Lee, Dong Soo;Han, Sang Joon
    • 한국해양학회지
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    • v.13 no.2
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    • pp.11-16
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    • 1978
  • The contents of heavy metals were studied on sediments collected from the southeastern coastal area of Korea.Concentrations of the elements showed Cu 14∼ 48ppm (av. 18ppm), Pb 14∼49ppm (av. 28ppm), Zn 79∼187ppm (av. 11ppm), Co 11∼ 15ppm (av. 13ppm), Ni 22∼32ppm (av. 29ppm), Fe 3.1∼5.3% (av. 4.3%) and Mn 333 ∼1010ppm (av. 499ppm). When these values are compared with those of the unpolluted near-shore sediments from other countries,there seems to be little environmental contamination of heavy metals in the sediments of the study area. However, from the fact that the nearer to harbor the stations are, the higher the contents of copper, lead and zinc are in the sea off Pusan Bay, it is suggested that heavy metals in the sediments are starting to show some contamination from man's activities.

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Fabrication of PZT Film by a Single-Step Spin Coating Process

  • Oh, Seung-Min;Kang, Min-Gyu;Do, Young-Ho;Kang, Chong-Yun;Nahm, Sahn;Yoon, Seok-Jin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.193-193
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    • 2011
  • To obtain ceramic films, the sol-gel coating technique has been broadly used with heat treatment, but crack formation tend to occur during heat treatment in thick sol-gel films. We prepared PZT thin films by sol-gel method with single-step spin coating process. The PZT solution have been synthesized using lead acetate ($Pb(CH_3COO)_2$), zirconium acetylacetonate ($Zr(OC_3H_7^n)_4$), and titanium diisopropoxide bis(acetylacetonate) 75wt% in isopropanol ($Ti(OC_3H_7^i)_2(OC_3H_7^n)_2$) as starting materials and n-propanol was selected as a solvent. The poly(vynilpyrrolidone) (PVP) was added with 0, 0.25, 0.5, 0.75, and 1 molar ratios to control viscosity of solution. We investigated influence of the viscosity on thickness, microstructure, and electrical properties of final PZT films. Thermo-gravimetric analysis and differential scanning calorimeter (TGA/DSC) was carried out from room temperature to $800^{\circ}C$ in order to measure pyrolysis temperature. Structural characteristics were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Ferroelectric and dielectric properties were measured by RT66A (Radiant) and impedance analyzer (Agilent), respectively. The thicknesses of PZT films depended on incorporation of an excess amount of PVP. Finally, we obtained PZT films of good quality without crack formation via single-step spin coating.

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Studies on Heavy Metal Contamination of Agricultural Products, Soils and Irrigation Waters in Abandoned Mines (폐광산지역 농산물, 토양 및 농경수의 중금속오염에 관한 연구)

  • 김미혜;소유섭;김은정;정소영;홍무기
    • Journal of Food Hygiene and Safety
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    • v.17 no.4
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    • pp.178-182
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    • 2002
  • This study was conducted to estimate the status of heavy metal contamination in agricultural products (n = 280), soils (n = 280), and irrigation waters (n = 48) in abandoned mines & normal farm lands (n = 8). The samples were digested with acids, then analyzed fur the contents of lead (Pb), cadmium (Cd), copper (Cu), mercury (Hg), arsenic (As) and chrome (Cr) by an inductively coupled plasma spectrometer (ICP) and graphite- atomic absorption spectrophotometer (AAS). The contents of Hg were determined using a mercury analyzer. Abandoned mines had soils with higher contents of heavy metals except Cr and irrigation waters with higher heavy metals except Hg, compared to those of normal farmlands. The contents of heavy metals in agriculture products varied depending types of products. Agricultural products in abandoned mines generally showed with higher contents of heavy metals except Cu, compared to those of normal farmlands. There was no significant relationship in heavy metal contents between agricultural products and soils (p > 0.05). It is suggested that heavy metals of agricultural products and soils in abandoned mines should be continuously monitored.

Determination of Aflatoxin M1 and Heavy Metals in Infant Formula Milk Brands Available in Pakistani Markets

  • Akhtar, Saeed;Shahzad, Muhammad Arif;Yoo, Sang-Ho;Ismail, Amir;Hameed, Aneela;Ismail, Tariq;Riaz, Muhammad
    • Food Science of Animal Resources
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    • v.37 no.1
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    • pp.79-86
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    • 2017
  • Aflatoxin $M_1$ ($AFM_1$) after its bioconversion from aflatoxin $B_1$ in animal liver becomes the part of milk while heavy metals get entry into milk and milk products during handling in the supply chain. Aflatoxin $M_1$ and heavy metals being toxic compounds are needed to be monitored continuously to avoid any ailments among consumers of foods contaminated with such toxicants. Thirteen commercially available infant formula milk (IFM) brands available in Pakistani markets were analyzed for the quantitative determination of $AFM_1$ and heavy metals through ELISA and atomic absorption spectrophotometer, respectively. $AFM_1$ was found positive in 53.84% samples while 30.76% samples were found exceeding the maximum EU limit i.e. $0.025 {\mu}g/kg$ for $AFM_1$ in IFM. Heavy metals lead (Pb) and cadmium (Cd) were found below the detection limits in any of the sample, whereas the concentrations of iron (Fe), zinc (Zn) and nickel (Ni) ranged between 45.40-97.10, 29.72-113.50 and <$0.001-50.90 {\mu}g/kg$, respectively. The concentration of Fe in all the tested brands was found in normal ranges while the concentrations of Zn and Ni were found exceeding the standard norms. Elevated levels of $AFM_1$, Zn and Ni in some of the tested IFM brands indicated that a diet completely based on these IFM brands might pose sever health implications in the most vulnerable community i.e., infants.