• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.296-300
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• 2002

Bacterial cell surface components are the major factors responsible for pathogenesis and bioremediation. In particular, the surface of a Gram-negative bacterium cell has a variety of components compared to that of a Gram-positive cell. In our previous study, we isolated an isogenic mutant of Bradyrhizobium japonicum, which exhibited altered cell surface characteristics, including an increased hydrophobicity. Polyacrylamide gel electrophoretic analysis of the lipopolysaccharide (LPS) in the mutant demonstrated that the O-polysaccharide part was completely absent. Meanwhile, a gel permeation chromatographic analysis of the exopolysaccharide (EPS) in the mutant demonstrated that it was unaltered. Since LPSs are known to have several anion groups that interact with various cation groups and metal ions, the mutant provided an opportunity to examine the direct role of LPS in metal binding by B. japonicum. Using atomic absorption spectrophotometry, it was clearly demonstrated that LPS was involved in metal binding. The binding capacity of the LPS mutant to various metal ions $(Cd^{2+},\;Cu^{2+},\;Pb^{2+},\;and\;Zn^{2+})$ was 50-70% lower than that of the wild-type strain. Also, through an EPS analysis and desorption experiment, it was found that EPS and centrifugal force had no effect on the metal binding. Accordingly, it would appear that LPS molecules on B. japonicum effect the properties, which precipitate more distinctly metal-rich mineral phase.

• 한국식품위생안전성학회지
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• 제3권1호
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• pp.7-18
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• 1988

식품중의 중금속 오염물질에 대한 추이를 감시하여 식품의 안전성을 확보하고 건강상의 위해를 방지하기 위한 노력을 계속하고 수산식품중 견류중의 중금속 분포상태를 파악하기 위해국내 주요 연안에서 자연서식 또는 인공 양식되고 있는 패류 9종 200건을 대상으로 Hg, Pb, Cd, As, Cu, Sn, Mn의 7개 중금속을 ICP, Spectrophotometer를 사용하여 측정한 결과는 다음과 같다. 1. Hg의 전체 함량범위는 ND~0.221 ppm이었고, 각 패류별 평균 함유량은 피조개 0.011 ppm, 꼬막 0.013 ppm, 전복 0.014 ppm, 홍합 0.018 ppm, 바지락과 굴이 0.025 ppm, 백합이 0.056 ppm, 소라고둥 0.074 ppm,골뱅이 0.090 ppm 이었다. 2. Pb의 전체 함량 범위는 0.05~1.15 ppm 이었으며 각 패류별 평균함량은 골뱅이, 꼬막이 각각 0.26~0.28 ppm 피조개, 소라고둥, 전복, 홍합이 0.32~0.33 ppm, 굴이 0.43 ppm, 바지락이 0.52 ppm , 백합이 0.53 ppm이었다. 3.Cb의 전체 함량범위는 0.02~1.86 ppm이었으며, 각 패류별 평균함량은 바지락 0.14 ppm, 홍합 0.19 ppm, 홍합 0.30 ppm, 피조개 0.53 ppm, 골뱅이 0.57 ppm, 전복, 굴 , 소라고둥이 0.78~0.80 ppm이며 꼬막이 1.37 ppm으로 가장 높았다. 4. As의 전체 함량의 범위는 0.50~3.97 ppm이었으며 각 패류별 평균함량은 홍합 0.65 ppm, 백합 0.72 ppm, 피조개 0.77 ppm 꼬막 0.79 ppm, 굴 0.88 ppm, 바지락 10.29 ppm, 전복 1.49 ppm, 골뱅이 2.11 ppm 소라고둥 2.30 ppm이었다. 5. Cu의 전체 함량 범위는 0.16~54.16 ppm 이었으며 패류별 평균함량은 피조개 0.95 ppm, 꼬막 1.10 ppm, 홍합 1.38 ppm, 백합 1.58 ppm, 바지락이 1.78 ppm, 전목이 53 ppm, 골뱅이 9.89 ppm, 소라고둥은 9.73 ppm, 굴에서 13.96 ppm, 골뱅이 9.89 ppm,소라고둥은 9.73 ppm , 굴에서 13.96 ppm으로 가장 높았다. 6.Sn의 전체 함량의 범위는 7.40~207.17 ppm이었으며, 패류별 평균함량은 바지락 12.16 ppm, 꼬막 14.98 ppm, 백합이 15.84 ppm, 피조개 16.58 ppm, 홍합 18.84 ppm, 전복이 21.46 ppm, 골뱅이 29.71 ppm, 소라고둥이 37.77 ppm 굴이 96.58 ppm으로 가장 높았다. 7. Mn의 전체 함량 범위는 0.13~8.72 ppm이었고 각 패류별 평균함량은 전복 0.96 ppm, 소라고둥 1.48 ppm, 홍합 2.25 ppm, 골뱅이 2.46 ppm, 피조개 2.80 ppm 백합 3.04 ppm, 바지락 4.44 ppm, 꼬막 6.06 ppm, 굴 6.66 ppm이었다. 8. 측정된 패류중의 중금속 분포결과와 기타 국내에서 보고된 분석치, 외국의 분석치 및 현제치를 종합적으로 비교 검토하여 볼 때 최고치에 있어서 다소 높은 것도 있었으나 평균함량과 90%치에 있어서는 문제시 될 수 있는 량은 아니었다. 9. 패류중 산지별로 다소 높은치를 나타낸 것에 대하여는 계속적인 조사연구가 필요하다고 생각된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.463-463
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• 2014

Dye-sensitized solar cells (DSSCs) have generated a strong interest in the development of solid-state devices owing to their low cost and simple preparation procedures. Effort has been devoted to the study of electrolytes that allow light-to-electrical power conversion for DSSC applications. Several attempts have been made to substitute the liquid electrolyte in the original solar cells by using (2,2',7,7'-tetrakis (N,N-di-p-methoxyphenylamine)-9-9'-spirobi-fluorene (spiro-OMeTAD) that act as hole conductor [1]. Although efficiencies above 3% have been reached by several groups, here the major challenging is limited photoelectrode thickness ($2{\mu}m$), which is very low due to electron diffusion length (Ln) for spiro-OMeTAD ($4.4{\mu}m$) [2]. In principle, the $TiO_2$ layer can be thicker than had been thought previously. This has important implications for the design of high-efficiency solid-state DSSCs. In the present study, we have fabricated 3-D Transparent Conducting Oxide (TCO) by growing tin-doped indium oxide (ITO) nanowire (NWs) arrays via a vapor transport method [3] and mesoporous $TiO_2$ nanoparticle (NP)-based photoelectrodes were prepared using doctor blade method. Finally optimized light-harvesting solid-state DSSCs is made using 3-D TCO where electron life time is controlled the recombination rate through fast charge collection and also ITO NWs length can be controlled in the range of over $2{\mu}m$ and has been characterized using field emission scanning electron microscopy (FE-SEM). Structural analyses by high-resolution transmission electron microscopy (HRTEM) and X-Ray diffraction (XRD) results reveal that the ITO NWs formed single crystal oriented [100] direction. Also to compare the charge collection properties of conventional NPs based solid-state DSSCs with ITO NWs based solid-state DSSCs, we have studied intensity modulated photovoltage spectroscopy (IMVS), intensity modulated photocurrent spectroscopy (IMPS) and transient open circuit voltages. As a result, above $4{\mu}m$ thick ITO NWs based photoelectrodes with Z907 dye shown the best performing device, exhibiting a short-circuit current density of 7.21 mA cm-2 under simulated solar emission of 100 mW cm-2 associated with an overall power conversion efficiency of 2.80 %. Finally, we achieved the efficiency of 7.5% by applying a CH3NH3PbI3 perovskite sensitizer.

• 한국식품과학회지
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• 제46권1호
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• pp.108-114
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• 2014

오이와 고추의 안전성에 영향을 미치는 위해요소 분석의 기초자료로 활용하기 위해 오이와 고추 재배지에서 총 72점의 시료를 채취하여 미생물학적(위생지표세균, 병원성미생물, 곰팡이) 위해요소와 화학적(중금속, 잔류농약) 위해요소를 조사하였다. 미생물학적 위해요소 중 위생지표세균과 곰팡이는 오이 재배지에서 ND-7.2와 ND-4.8 log CFU/g (g, mL, hand, or $100cm^2$) 범위로 검출되었고, 고추 재배지에서는 ND-6.8와 0.4-5.3 log CFU/g (g, mL, hand, or $100cm^2$) 범위로 검출되었다. 특히 대장균군은 고추재배지의 토양에서 최대 5.6 log CFU/g까지 검출되었다. 병원성 미생물은 S. aureus는 오이 농장의 장갑에서만 1.4 log CFU/$100cm^2$으로 검출되었고, B. cereus는 대부분의 시료에서 ND-4.8 log CFU/g (g, mL, hand, or $100cm^2$) 범위로 검출되었다. L. monocytogenes, E. coli O157:H7 및 Salmonella spp.는 검출되지 않았다. 화학적 위해요소에 해당하는 중금속은 Zn, Cu, Ni, Pb 및 Hg이 국내 허용기준치 이하로 검출되었고, 잔류농약의 경우 오이에서는 모든 성분이 불검출 되었으나 고추에서 hexaconazole 성분이 0.016 mg/kg (기준치: 0.3 mg/kg)으로 검출되었다.

• 한국토양비료학회지
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• 제36권5호
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• pp.323-332
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• 2003

전국적으로 산재해있는 2,000여 광산지역의 경우 중금속 오염의 정도와 범위를 고려할 때, 기존의 물리 화학적 복원기술의 적용만으로는 경제성과 실효성의 조화가 어렵다. 이에 기존의 토양 복원기술과 더불어 생물학적 복원기술로써 phytoremediation 기술의 개발이 요구된다. 본 연구는 경기도 광명시에 위치한 폐아연광산 인근 토양 및 식물체내의 중금속 함량과 토양내 Cd의 존재형태별 분포를 파악하여 인근 농경지로의 잠재적 오염원이 되는 부지를 선정하고, 오염 토양에 대한 phytoremediation 적용을 위한 기초 조사를 수행하였다. 17지점에서 채취한 논 밭 및 비경작지 토양의 0.1 N-HCl 추출 Cd 함량은 $0.2-42mg\;kg^{-1}$의 분포를 보였고, Cd 함량이 상대적으로 높은 비경작지 토양의 중금속 함량은 Zn $533-2320mg\;kg^{-1}$, Pb $560-3584mg\;kg^{-1}$, Cu $104-1277mg\;kg^{-1}$, Cd $11-42mg\;kg^{-1}$의 범위로 나타났다. pH를 1에서 3까지 조절하며 수행한 중금속 용출시험 결과 pH 변화에 따른 중금속 용출의 정도는 매우 컸다. 대부분의 토양은 유기물 및 질소함량이 극히 낮고, 평균 토성은 사양토로 전국적으로 분포하는 광산토양의 평균 이화학성 범위 내에 있어 Cd, Zn 및 Pb의 생물학적 복원부지로서의 적합성을 보였다. 본 연구에서 정화식물종으로 선별한 식물은 아연광산에 서식하는 대표적 초본류인 쑥이며, 체내 중금속 함량은 지상부 $43mg\;kg^{-1}$, 지하부 $52mg\;kg^{-1}$의 Cd 함량을 보였다. 채취한 식물체 주변 근권 토양 (rhizosphere soil)과 경계면 토양 (soil-root interface soil)은 각각 15.68, $14.09mg\;kg^{-1}$의 Cd 함량을 나타내었다. 토양에 대한 연쇄추출 결과 $H_2O$(water soluble), NaOH (organically bound), $KNO_3$ (exchangeable), EDTA (oxide/carbonate), $HNO_3$ (sulfide/residual)의 순으로 Cd 추출효율이 증가하였으며, 토양내 치환태 Cd는 평균 $2.4mg\;kg^{-1}$으로 나타났다. 중금속 오염부지에 대한 식물 식재시 퇴비의 투여량은 지하부 표면적 및 뿌리부피와 밀접한 상관관계를 나타내어 오염 토양내 식피조성시 식물체의 활착율을 증대 시킬 수 있을 것으로 사료된다.

• Journal of Plant Biology
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• 제19권1호
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• pp.1-6
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• 1976

This study was carried out to investigate the formation of precipitates between lead ion and the essential anions of plants, the effects of lead concentration on seed germination and plant growth in water and soil culture, and the germinating and growing recovery of inhibited seed germination and plant growth by lead. Four kinds of the seeds (Glycine max M., Triticum vulgare V., Setaria viridis (L) P. De Beauvois, and Digitoria sanguinalis (L) Scopoli var) were germinated and growth in water and soil culture included the different concentrations of lead for five days. The seeds and plants inhibited germination and growth by lead were transferred to lead free Hoagland solution and the growing recovery was observed. The precipitates of lead ion were observed in the solution of both acidity and alkalinity included each anion of $H_2PO_4^-, HPO_4^{2-}, PO_4^{3-}, SO_4^{2-} and MoO_4^{2-}$ in a room temperature, whereas the precipitates between lead ion and other anions were observed largely in the solution of alkalinity, so that it seemed that lead could be remained in the state of non-soluble in plant and soil. The inhibition of germination and growth in the water culture was observed in 100ppm of lead, whereas the inhibition in the case of the soil culture was observed in 10000ppm of lead. The difference of the effected concentration between water and soil culture in germination and the growth was 100 times. When the seed and plant inhibited the growth in 5000ppm or 10000ppm of lead for five days were transferred to lead free Hoagland solution, the recovery of germination and growth was observed in three days. This growing recovery was different according to the kinds of plant and concentrations of lead. It seemed that plant growth could be inhibited by the inhibition of the metabolism concerned with the precipitates between lead iion and other anions.

• Journal of Preventive Medicine and Public Health
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• 제15권1호
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• pp.131-137
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• 1982

For the purpose of the curative effects of oral D-penicillamine in lead poisoning, D-penicillamine was orally administered to 7 lead poisoned workers which were employed in glaze product industry dealing with the lead oxide ($Pb_3O_4$). The doses of D-penicillamine was 1,200mg per day which was administered by oral 7days schedules, taking for 5 days and stopping for the following 2days, repeatedly during 3 months period. (All the poisoned workers started working again in that industry after 1 month treatment, and were treated by oral D-penicillamine for 2 months still being exposed to contaminated environment.) In order to evaluate the curative effects of D-penicillamine, 10gm of whole blood and 24 hours urine were collected every 14 days during the curative period for laboratory analysis(hemoglobin, blood lead, urine $\sigma$-aminolevulinic acid, urine coproporphyrin, and urine lead levels) with the observation of the clinical symptoms. The results were as follows; 1. Oral D-penicillamine effected good curative results as that hemoglobin, blood lead, urine $\sigma$-aminolevulinic acid, and urine coproporphyrin levels were decreased below the critical level within 1 month treatment. 2. After re-exposure, oral D-penicillamine effected to some extent as that urine lead level was decreased below the critical level after 3 months treatment with disappearence of the clinical symptoms after 2 months treatment. However, the curative effects of oral D-penicillamine in the lead exposure state is questionable since increasement of blood lead level and remarkable decreasement of urine lead level after 3 months treatment can be observed.

• 자원환경지질
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• 제29권2호
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• pp.139-150
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• 1996

The Yucheon Bi deposits at Cheongha, Gyeongsangbugdo, is of a middle Paleogene (49 Ma) vein type, and is hosted in sandstone and shale of Banyawal formation in Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, two minera1ization stages were distinguished. The stage I consists of quartz with small amount of chlorite, pyrite, epidote, hal1oysite, vermiculite, serpentine and rutile associated with sericitization. The stage II is characterized by Bi minera1ization such as bismuthinite, Bi-Cu-Pb-S mineral, tetradymite, native gold, pyrite, pyrrhotite, arsenopyrite, wolframite, rutile, hematite, sphalerite, chalcopyrite, galena with alteration of sericite, chlorite, K-feldspar, albite and epidote. Fluid inclusion data indicate that fluid temperature and NaCl equivalent wt.% salinity range from 431 to $150^{\circ}C$ and from 19.2 to 0.18wt.% in the stage II. Evidence of boiling during the base-metal minera1ization indicates pressures 241 to 260 bars. Sulfur fugacity($-log\;f_{S2}$) deduced by mineral assemblages and compositions ranges from 5.1 to 5.7atm in early stage, from > 8.4 atm in middle stage and from 13.5 to 19.3 atm in late stage. It suggests that complex histories of progressive coo1ing, dilution and boiling were occurred by the mixing of the fluids. The ${\delta}^{34}S$, ${\delta}^{18}O$ and ${\delta}D$ data range from 2.5 to 3.9%, -0.5 to -4.1% and -29.7 to -47%, respectively. It indicated that hydrothermal fluids may be magmatic origin with boiling and mixing of meteoric water increasing paragenetic time.

• 치위생과학회지
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• 제13권2호
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• pp.203-212
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• 2013

한국 땃쥐속 우수리땃쥐 Crocidura lasiura와 작은땃쥐 C. suaveolens, 뒤쥐속 뒤쥐 Sorex caecutiens의 치아형태와 법랑질 표면의 함유물을 EDX를 이용하여 정성 분석하였다. 우수리땃쥐와 작은땃쥐의 경우, 치식은 I3/1 C1/1 P1/1 M3/3=28이었고, 상악 제1대구치와 제2대구치는 5개의 교두들로 만들어진 균형이 맞지 않는 W형을 가지고 있었고, 상악 제3 대구치는 상악 제1대구치와 제2대구치의 3/1크기였으며, 상악 제1절치는 2개의 다른 크기의 갈고리 모양이었으며, 하악 제1 절치는 매끈하였다. 뒤쥐의 경우, 치식은 I3/1 C1/1 P3/1 M3/3=32이었고, 상악 제1대구치와 제2대 구치는 균형이 맞는 W형을 가졌고 상악 제3대구치는 다른 대구치의 약 절반 크기였으며, 상악 제1절치는 2개의 비슷한 크기의 갈고리 모양이었으며 하악 제1절치는 매끈하지않은 톱니모양이었다. 치아와 두개골 측정치 비교에서 우수리땃쥐가 3종 중 가장 컸으나(p<0.001), 작은땃쥐와 뒤쥐는 크기에서 차이가 없었다(p>0.05). EDX를 이용한 하악 제1절치와 하악 제1대구치의 법랑질 표본의 정성적 분석으로부터, C, O, P, Ca, Cu가 모든 표본에서 검출되었고 Pb는 몇몇 표본에서만 검출되었다. 3종들에서 이들의 함유량은 통계적 차이를 보이지 않았다(p>0.05). Fe는 붉게 착색된 치아를 가지는 뒤쥐의 법랑질 표면에서만 검출되었다. 따라 서 Fe가 치아의 붉은 착색의 원인이다. 이상의 결과들은 치아 끝의 색을 포함한 치아 형태학적 특징들이 땃쥐속과 뒤쥐속의 분류키가 될 수 있음을 시사하고 있다.

• 한국수산과학회지
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• 제43권2호
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• pp.146-158
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• 2010

In order to evaluate the characteristics of sediments and pollution by organic matter and metallic elements in intertidal sediments along the southwestern coast of Korea, we measured various geochemical parameters, including the mean grain size (Mz), water content (WC), ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and metallic elements (Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, As), in intertidal surface sediments. The Mz of the surface sediments ranged from 2.1 to 8.3$\phi$, indicating that the surface sediments consist of various sedimentary facies, such as sand, slightly gravelly mud, sandy mud, and silt. The IL and COD in surface sediment ranged from 0.8 to 5.5% (mean $2.9\pm1.2%$) and from 3.9 to $13.8\;mgO_2/g{\cdot}dry$ (mean $8.5\pm2.6\;mgO_2/g{\cdot}dry$), respectively, which were lower than the values for surface sediment in areas near fish and shellfish farms or industrial complexes. No AVS was detected at any sampling station, despite various sedimentary facies. Most of metallic elements in surface sediments showed relatively good positive correlations with Mz and IL, which imply that the concentrations of metallic elements are mainly controlled by grain size and the organic matter content. The concentrations of metallic elements, except As, at some stations were considerably lower than those in the Sediment Quality Guideline (Effect Range Low, ERL) proposed by the National Oceanic and Atmospheric Administration (NOAA) in the United States. Similarly, the geoaccumulation index (Igeo) class indicated that pollution by metallic elements in intertidal surface sediment, except As, was moderate or non-existent. Our results imply that the intertidal surface sediments along the southwestern coast of Korea are not polluted by organic matter and metallic elements and are healthy for benthic organisms.