• Title/Summary/Keyword: Lead extraction

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Characterization of Mineralogical and Physicochemical Properties of Soils Contaminated with Metals at Gahak Mine (가학광산 주변 중금속 함유 토양입자의 이화학적·광물학적 특성연구)

  • Lee, Choong Hyun;Lee, Seon Yong;Park, Chan Oh;Kim, Jong Won;Lee, Sang Hwan;Park, Mi Jeong;Jung, Moon Young;Lee, Young Jae
    • Journal of Soil and Groundwater Environment
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    • v.20 no.4
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    • pp.83-89
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    • 2015
  • Soil samples collected in an area of Gahak Mine were investigated for the characterization of mineralogical and physicochemical properties of contaminants in soils. It is found that soils in the study area are contaminated by lead (Pb), copper (Cu), zinc (Zn), cadmium (Cd), in which their concentrations are 595.3 mg/kg, 184.9 mg/kg, 712.8 mg/kg, and 10.64 mg/kg, respectively. All the concentrations exceed the concern criteria of Korean standard. Upon distribution patterns of metals identified by the sequential extraction procedure, our results show that more than 50% of metals are found as a residual type, and 30% are accounted for the association of Fe/Mn oxides. Interestingly, XRD results show that minium (Pb3O4) and cuprite (Cu2O) are identified in the soil samples, suggesting that the sources of the contaminants for Pb and Cu are these minerals. In SEM images, tens of µm of Pb oxides and Pb silicate-minerals are observed. We, therefore, note that the contamination of metals in the study area results from the direct influx and disturbance of tailings. Our findings indicate that the characterization of physicochemical and mineralogical properties of contaminated soils is a critical factor and plays an important role in optimizing recovery treatments of soils contaminated in mine development areas.

Dispersion and Enrichment of Potentially Toxic Elements in the Chungjoo Area Covered with Black Shales in Korea (충주지역 흑색셰일 분포지역에서의 잠재적 독성원소들의 분산과 부화)

  • Lee, Jin-Soo;Chon, Hyo-Taek;Kim, Kyoung-Woong
    • Economic and Environmental Geology
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    • v.29 no.4
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    • pp.495-508
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    • 1996
  • This study had three purposes: (1) to investigate dispersion and enrichment level of potentially toxic elements; (2) to identify uranium-bearing minerals in black shales; and (3) to assess the chemical speciation of heavy metals in soils and sediments. Rock, surface soil and stream sediment samples were collected in the Chungjoo area covered with black shales in Korea. These samples were analyzed for multi-elements using INAA and ICP-AES. The maximum abundance of U in black shales is 56 ppm and radioactivity counts up to 240CPM. Molybdenum, V, Ba, Cu, and Pb are enriched in black shales and most of soils show high concentrations of U, Mo, Ba, Cu, Pb and Zn. Concentrations of potentially toxic elements decrease in the order of mountain soil > farmland soil > paddy soil. Enrichment index of soils and sediments are calculated and higher than 1.0 in the black shale area with the highest value of 6.1. In order to identify U-bearing minerals, electron probe micro analysis was applied, and uraninite and brannerite in black shale were found. Uraninite grains are closely associated with monazite or pyrite with the size of $2{\mu}m$ to $10{\mu}m$ in diameter whereas brannerite occurs as $50{\mu}m$ euhedral grains. With the results of sequential extraction scheme, residual fractions of Cu, Pb and Zn in soils are mainly derived from weathering of black shale but Cu, Pb and Zn in sediments are present as non-residual fractions. Lead is predominantly present as oxidizable phase in soils whereas Zn is in exchageable/water-acid soluble phase in sediments.

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Analysis of Accuracy and DTM Generation Using Digital Photogrammetry (수치사진 측량을 이용한 DTM 추출 및 정확도 분석)

  • Park, Jin-Seong;Hong, Sung-Chang;Sung, Jae-Ryeol;Lee, Byung-Hwan
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.301-306
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    • 2010
  • Recently GIS is not only displaying and servicing data on the 2D, but also is changing rapidly to display and service 3D data. Also 3D related technology is developing actively. For display of 3D data, terrain DTM has become a basis. Generally, to acquire DTM, users are using LIDAR data or digital map's contour line. However, if using these data for producing DTM, users need to additional cost and data lead time. And hard to update terrain data. For possibility of solving these problem, this study did DTM extraction with automatic matching for aerial photograph, and analysed the result with measurement of Orthometric height and excuted accuracy through DTM(which extracted from digital photogrammetric technique). As a result, we can get a high accuracy of RMSE (0.215m).

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Development of an experimental model for radiation-induced inhibition of cranial bone regeneration

  • Jung, Hong-Moon;Lee, Jeong-Eun;Lee, Seoung-Jun;Lee, Jung-Tae;Kwon, Tae-Yub;Kwon, Tae-Geon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.40
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    • pp.34.1-34.8
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    • 2018
  • Background: Radiation therapy is widely employed in the treatment of head and neck cancer. Adverse effects of therapeutic irradiation include delayed bone healing after dental extraction or impaired bone regeneration at the irradiated bony defect. Development of a reliable experimental model may be beneficial to study tissue regeneration in the irradiated field. The current study aimed to develop a relevant animal model of post-radiation cranial bone defect. Methods: A lead shielding block was designed for selective external irradiation of the mouse calvaria. Critical-size calvarial defect was created 2 weeks after the irradiation. The defect was filled with a collagen scaffold, with or without incorporation of bone morphogenetic protein 2 (BMP-2) (1 ㎍/ml). The non-irradiated mice treated with or without BMP-2-included scaffold served as control. Four weeks after the surgery, the specimens were harvested and the degree of bone formation was evaluated by histological and radiographical examinations. Results: BMP-2-treated scaffold yielded significant bone regeneration in the mice calvarial defects. However, a single fraction of external irradiation was observed to eliminate the bone regeneration capacity of the BMP-2-incorporated scaffold without influencing the survival of the animals. Conclusion: The current study established an efficient model for post-radiation cranial bone regeneration and can be applied for evaluating the robust bone formation system using various chemokines or agents in unfavorable, demanding radiation-related bone defect models.

Estimation of Highland Kimchi Cabbage Growth using UAV NDVI and Agro-meteorological Factors

  • Na, Sang-Il;Hong, Suk-Young;Park, Chan-Won;Kim, Ki-Deog;Lee, Kyung-Do
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.5
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    • pp.420-428
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    • 2016
  • For more than 50 years, satellite images have been used to monitor crop growth. Currently, unmanned aerial vehicle (UAV) imagery is being assessed for analyzing within field spatial variability for agricultural precision management, because UAV imagery may be acquired quickly during critical periods of rapid crop growth. This study refers to the derivation of growth estimating equation for highland Kimchi cabbage using UAV derived normalized difference vegetation index (NDVI) and agro-meteorological factors. Anbandeok area in Gangneung, Gangwon-do, Korea is one of main districts producing highland Kimchi cabbage. UAV imagery was taken in the Anbandeok ten times from early June to early September. Meanwhile, three plant growth parameters, plant height (P.H.), leaf length (L.L.) and outer leaf number (L.N.), were measured for about 40 plants (ten plants per plot) for each ground survey. Six agro-meteorological factors include average temperature; maximum temperature; minimum temperature; accumulated temperature; rainfall and irradiation during growth period. The multiple linear regression models were suggested by using stepwise regression in the extraction of independent variables. As a result, $NDVI_{UAV}$ and rainfall in the model explain 93% of the P.H. and L.L. with a root mean square error (RMSE) of 2.22, 1.90 cm. And $NDVI_{UAV}$ and accumulated temperature in the model explain 86% of the L.N. with a RMSE of 4.29. These lead to the result that the characteristics of variations in highland Kimchi cabbage growth according to $NDVI_{UAV}$ and other agro-meteorological factors were well reflected in the model.

Semiquantitative Dynamic Headspace GC-MS Analysis for Organic Compounds Outgassed from FAB Materials of Air Shower (에어샤워부품의 용출 가스 중 유기화합물의 반 정량적 Headspace GC-MS 분석)

  • Park, Hyun-Mee;Baig, Soung-Woo;Kim, Young-Man;Lee, Kang-Bong
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.412-422
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    • 2000
  • The polymeric FAB materials of air shower used in clean room of wafer industry have been outgassed with the dynamic headspace (ca.$100^{\circ}C$) for half an hour, and analyzed using GC-MS. The air in the clean room running air shower was sampled using sorbent tube method, and the organic compounds adsorbed in the sorbent tube were extracted using Soxhlet extraction method, and analyzed using GC-MS. The analytical results from FAB materials of air shower (electric over current relay, acryl plate. polycarbonate window, filter, fan housing, steel galvanized cold plate and canvas buffer) indicated that most of chemicals were originated from polymer fragments of FAB materials. Their analytical results have been compared with those from the air of clean room running air shower. These comparative results could lead to identify whether the sources of trace organic contaminants in clean room air are originated from the polymeric FAB material of air shower.

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A visual query database system for the Sample Research DB of the National Health Insurance Service (국민건강보험공단의 표본연구DB를 위한 비주얼 쿼리 데이터베이스 시스템 개발 연구)

  • Cho, Sang-Hoon;Kim, HeeChan;Kang, Gunseog
    • The Korean Journal of Applied Statistics
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    • v.30 no.1
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    • pp.13-24
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    • 2017
  • The Sample Cohort DB supplied by the National Health Insurance Service is a valuable resource for statistical studies as well as for health and medical studies. It takes significant time and effort to extract data from this Cohort DB having a large size. As such, we introduce a database system, conveniently called the National Health Insurance Service Cohort DB Extract Tool (NICE Tool), which supports several useful operations for effectively and efficiently managing the Cohort DB. For example, researchers can extract variables and cases related with study by simply clicking a computer mouse without any prior knowledge regarding SAS DATA step or SQL. We expect that NICE Tool will facilitate the faster extraction of data and eventually lead to the active use of the Cohort DB for research purposes.

A Comparative Study on Forecasting Groundwater Level Fluctuations of National Groundwater Monitoring Networks using TFNM, ANN, and ANFIS (TFNM, ANN, ANFIS를 이용한 국가지하수관측망 지하수위 변동 예측 비교 연구)

  • Yoon, Pilsun;Yoon, Heesung;Kim, Yongcheol;Kim, Gyoo-Bum
    • Journal of Soil and Groundwater Environment
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    • v.19 no.3
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    • pp.123-133
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    • 2014
  • It is important to predict the groundwater level fluctuation for effective management of groundwater monitoring system and groundwater resources. In the present study, three different time series models for the prediction of groundwater level in response to rainfall were built, those are transfer function noise model (TFNM), artificial neural network (ANN), and adaptive neuro fuzzy interference system (ANFIS). The models were applied to time series data of Boen, Cheolsan, and Hongcheon stations in National Groundwater Monitoring Network. The result shows that the model performance of ANN and ANFIS was higher than that of TFNM for the present case study. As lead time increased, prediction accuracy decreased with underestimation of peak values. The performance of the three models at Boen station was worst especially for TFNM, where the correlation between rainfall and groundwater data was lowest and the groundwater extraction is expected on account of agricultural activities. The sensitivity analysis for the input structure showed that ANFIS was most sensitive to input data combinations. It is expected that the time series model approach and results of the present study are meaningful and useful for the effective management of monitoring stations and groundwater resources.

A Case Repot of Chronic Unhealing Wound Related to Odontogenic Cutaneous Sinus Tract (치원성 표피 누공과 연관된 만성 창상의 증례보고)

  • Jeong, Boh-Rham;Kim, Young-Seok;Hong, Jong-Won;Roh, Tai-Suk;Rah, Dong-Kyun
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.523-526
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    • 2011
  • Purpose: The odontogenic sinus and fistulous tracts is the most common draining sinus and fistulous tract of the head and neck region. These are often misdiagnoses by clinicions who are not familiar with cutaneous sinus, since most of patients do not have dental symptoms. Here we present two cases of odontogenic cutaneous sinus tract which have been diagnosed after excision of epidermal cyst. Methods: Two patients who presented with an odontogenic sinus tract draining to the skin at our institusion during the two years were enrolled in this study. We reviewed all the medical records of the patients and literature about odontogenic cutaneous sinus tract. Results: Odontogenic cutaneous sinus tracts of our cases were healed after treatment of periapical odontitis and extraction of the carious tooth. Conclusion: The cutaneous sinus tract of dental origin is well documented condition. But its diagnosis is not always easy unless the clinicians consider the possibility of its dental origin. An understanding of the pathogenesis of odontogenic cutaneous sinus tract will lead to early correct diagnosis and proper treatment without unnecessary surgery.

Internal Amplification Control for a Cryptosporidium Diagnostic PCR: Construction and Clinical Evaluation

  • Hawash, Yousry;Ghonaim, M.M.;Al-Hazmi, Ayman S.
    • Parasites, Hosts and Diseases
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    • v.53 no.2
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    • pp.147-154
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    • 2015
  • Various constituents in clinical specimens, particularly feces, can inhibit the PCR assay and lead to false-negative results. To ensure that negative results of a diagnostic PCR assay are true, it should be properly monitored by an inhibition control. In this study, a cloning vector harboring a modified target DNA sequence (${\approx}375bp$) was constructed to be used as a competitive internal amplification control (IAC) for a conventional PCR assay that detects ${\approx}550bp$ of the Cryptosporidium oocyst wall protein (COWP) gene sequence in human feces. Modification of the native PCR target was carried out using a new approach comprising inverse PCR and restriction digestion techniques. IAC was included in the assay, with the estimated optimum concentration of 1 fg per reaction, as duplex PCR. When applied on fecal samples spiked with variable oocysts counts, ${\approx}2$ oocysts were theoretically enough for detection. When applied on 25 Cryptosporidium-positive fecal samples of various infection intensities, both targets were clearly detected with minimal competition noticed in 2-3 samples. Importantly, both the analytical and the diagnostic sensitivities of the PCR assay were not altered with integration of IAC into the reactions. When tried on 180 randomly collected fecal samples, 159 were Cryptosporidium-negatives. Although the native target DNA was absent, the IAC amplicon was obviously detected on gel of all the Cryptosporidium-negative samples. These results imply that running of the diagnostic PCR, inspired with the previously developed DNA extraction protocol and the constructed IAC, represents a useful tool for Cryptosporidium detection in human feces.