• Title/Summary/Keyword: ZnO/Cu/ZnO

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Adsorption Characteristics of Heavy Metal Ions onto Chemically Modified Rice Husk and Sawdust from Aqueous Solutions (화학적으로 개질된 왕겨 및 톱밥(미송, 참나무, 포플러)의 중금속 흡착특성)

  • Lee, Hyeon-Yong;Jeon, Choong;Lim, Kyoung-Jae;Hong, Ki-Chan;Lim, Jung-Eun;Choi, Bong-Su;Kim, Nam-Won;Yang, Jae-E;Ok, Yong-Sik
    • Korean Journal of Environmental Agriculture
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    • v.28 no.2
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    • pp.158-164
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    • 2009
  • Biosorption uses adsorbents derived from non-living biomass and removes toxic metals from industrial wastewater. The objective of this research was to evaluate the potential of low cost biosorbents to remove heavy metal ions (Cd, Cu, Pb and Zn) from aqueous solutions using chemically modified rice husk and saw dust (Pseudotsuga menziesi, Quercus, Populus). Batch-type adsorption experiments were carried out using rice husk and saw dust treated with NaOH and/or tartaric acid in artificial wastewater 100 mg metal/L). The experimental results showed that the adsorption specificity of each biosorbent was Pb > Cu > Cd > Zn irrespective of the types of biosorbents. The adsorption capacity of Pb and Cu onto NaOH-treated sawdust was increased 2${\sim}$3 times compared to the untreated one. In addition, the tartaric acid treatment increased the adsorption capacity of rice husk for Zn and Cd approximately 5${\sim}$10 fold compared to the untreated one. Surface conditions and changes in functional groups by chemical modification of each biosorbent were confirmed by SEM and FT-IR. Overall, the results show that chemical modification increases the metal removal capacity of rice bran and sawdust.

Petrochemistry and Environmental Geochemistry of Shale and Coal from the Daedong Supergroup, Chungnam Coal Field, Korea (충남탄전, 대동누층군의 셰일과 탄질암에 관한 암석화학 및 환경지구화학적 특성)

  • Lee, Chan Hee;Lee, Hyun Koo;Kim, Kyoung-Woong
    • Economic and Environmental Geology
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    • v.30 no.5
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    • pp.417-431
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    • 1997
  • Characteristics of sedimentary rocks and enrichment of toxic elements in shale and coal from the Chungnam coal field were investigated based upon geochemistry of major, trace and rare earth elements. Shale and coal of the area are interbedded along the Traissic to the Jurassic Daedong Supergroup, which can be subdivided into grey shale, black shale and coal. The coal had been mined, however all the mines are abandonded due to the economic problems. The shale and coal are characterized by relatively low contents of $SiO_2$, and $Al_2O_3$ and high levels of loss-on-ignition (LOI), CaO and $Na_2O$ in comparison with the North American Shale Composite (NASC). Light rare earth elements (La, Ce, Yb and Lu) are highly enriched with the coal. Ratios of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shale and coal range from 30.0 to 351.8 and from 4.2 to 106.8, which have partly negative correlations against $SiO_2/Al_2O_3$ (1.24 to 6.06), respectively. Those are suggested that controls of mineral compositions in shale and coal can be due to substitution and migration of those elements by diagenesis and metamorphism. Shale and coal of the area may be deposited in terrestrial basin deduced from high C/S (39 to 895) and variable composition of organic carbon (0.39 to 18.40 wt.%) and low contents of reduced sulfur (0.01 to 0.05 wt.%). These shale and coal were originated from the high grade metamorphic and/or igneous rocks, and the rare earth elements of those rocks are slightly influenced with diagenesis and metamorphism on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.38 to 0.85) and Th/U (3.6 to 14.6). Characteristics of trace and rare earth elements as Co/Th (0.07 to 0.86), La/Sc (0.31 to 11.05), Se/Th (0.28 to 1.06), V/Ni (1.14 to 3.97), Cr/V (1.4 to 28.3), Ni/Co (2.12 to 8.00) and Zr/Hf (22.6~45.1) in the shale and coal argue for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (1.36 to 21.68), Th/Yb (3.5 to 20.0) and La/Th (0.31 to 7.89), and their origin is explained by derivation from a mixture of mainly acidic igneous and metamorphic rocks. Average concentrations in the shale and coal are As=7.2 and 7.5, Ba=913 and 974, Cr=500 and 145, Cu=20 and 26, Ni=38 and 35, Pb=30 and 36, and Zn=77 and 92 ppm, respectively, which are similar to those in the NASC. Average enrichment indices for major elements in the shale (0.79) and coal (0.77) are lower than those in the NASC. In addition, average enrichment index for rare earth elements in coal (2.39) is enriched rather than the shale (1.55). On the basis of the NASC, concentrations of minor and/or environmental toxic elements in the shale and coal were depleted of all the elements examined, excepting Cr, Pb, Rb and Th. Average enrichment indices of trace and/or potentially toxic elements (As, Cr, Cu, Ni, Pb, U and Zn) are 1.23 to 1.24 for shale and 1.06 to 1.22 for coal, respectively.

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Electrical and Optical Properties with the Thickness of Cu(lnGa)$Se_2$ Absorber Layer (Cu(InGa)$Se_2$ 광흡수막의 두께에 따른 태양전지의 전기광학 특성)

  • Kim, S.K.;Lee, J.C.;Kang, K.H.;Yoon, K.H.;Park, I.J.;Song, J.;Han, S.O.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05c
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    • pp.108-111
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    • 2002
  • CIGS film has been fabricated on soda-lime glass, which is coated with Mo film. by multi-source evaporation process. The films has been prepared with thickness of 1.0 ${\mu}m$, 1.75${\mu}m$, 2.0${\mu}m$, 2.3${\mu}m$, and 3.0${\mu}m$. X-ray diffraction analysis with film thickness shows that CIGS films exhibit a strong (112) preferred orientation. Furthermore. CIGS films exhibited distinctly decreasing the full width of half-maximum and (112) preferred peak with film thickness. Also, The film's microstructure, such as the preferred orientation, the full width at half-maximum(FWHM), and the interplanar spacing were examined by X-ray diffraction. The preparation condition and the characteristics of the unit layers were as followings ; Mo back contact DC sputter, CIGS absorber layer : three-stage coevaporation, CdS buffer layer : chemical bath deposition, ZnO window layer : RF sputtering, $MgF_2$ antireflectance : E-gun evaporation

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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.

Study on Separation of Heavy Metal Ions in A Neutral Macrocycle-Mediated Emulsion Liquid Membrane System

  • Moon-Hwan Cho;Hea-Suk Chun;Jin-Ho Kim;Chang-Hwan Rhee;Si-Joong Kim
    • Bulletin of the Korean Chemical Society
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    • v.12 no.5
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    • pp.474-477
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    • 1991
  • The preferential transport phenomena of neutral cation-anion moieties in neutral macrocycle-facilitated emulsion liquid membrane were described in this study. Emulsion membrane systems consisting of (1) aqueous source phase containing 0.001 M M($NO_3$)$_2(M=Mn^{2+},\;Co^{2+},\;Ni^{2+},\;Cu^{2+},\;Zn^{2+},\;Sr^{2+},\;Cd^{2+},\;and\;Pb^{2+})$ (2) a toluene membrane containing 0.01 M ligand $(DBN_3O_2$, DA18C6, DT18C6, TT18C6, HT18C6) and the surfactant span 80 (sorbitan monooleate) (3% v/v) and (3) an aqueous receiving phase containing $Na_2S_2O_3$ or $NaNO_3$ were studied with respect to the disappearence of transition metal ions from the source phase as a function of time. Cation transports for various two component or three component equimolar mixture of transition metal and $Cu^{2+}$ in a emulsion membrane system incorporating macrocyclic ligand (HT18C6) as carrier were determinded. $Cu^{2+}$ was transported higher rates than the other $M^{2+}$ in the mixture solution. Equilibrium constants for cation-source phase co-anion, cation macrocycle and cation-receiving phase reagent interaction are examined as parameters for the prediction of cation transport selectivities.

Isolation and Degradation Characteristics of 2,4,4l-Trichloro-2l-Hydroxydiphenyl Ether Degrading Bacterium (2,4,4l-Trichloro-2l-Hydroxydiphenyl Ether 분해균의 분리 및 분해특성)

  • Han, Nan-Sook;Son, Hong-Joo;Lee, Geon;Lee, Sang-Joon
    • Journal of Environmental Science International
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    • v.6 no.2
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    • pp.173-182
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    • 1997
  • The bacterial strains, which utilizes 2,4,4'-trichloro-2'-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highestt biodegradation activity was designated as EL-O47R The isolated strain EL-O47R was Identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH4)2SO4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the regradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-O47R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-O47R was moderately grown to Cd(NO3)2, ZnCl2, AgSO4, CuSO4 and HgCl2. This strain was sensitive to rifampicin and kanamycln but resistant to ampicillin, penicillin, tetracyclin and chloramphenlcol. Pseudomonas sp. EL-O47R was grown structurally related com- pounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.

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Syntheses of Tetradentate Nitrogen-Oxygen(N2O2)) Ligands with Substituents and the Determination of Stability Constants of Their Heavy(II) Metal Complexes (치환기를 가진 질소-산소(N2O2)계 네 자리 리간드의 합성과 중금속(II)이온 착화합물의 안정도상수 결정)

  • Kim, Sun-Deuk;Seol, Jong-Min
    • Journal of Environmental Science International
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    • v.21 no.4
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    • pp.421-435
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    • 2012
  • Novel $N_2O_2$ tetradentate ligands, H-3BPD and H-2BPD were synthesized. Hydrochloric acid salts of Br-3BPD, Cl-3BPD, Br-2BPD and Cl-2BPD having Br and Cl substituents at the $para$ position of the phenol hydroxyl group, were synthesized. The ligands were characterized by C. H. N atomic analysis, $^1H$ NMR, $^{13}C$ NMR, UV-visible, and mass spectra. The proton dissociation constants ($logK_n{^H}$) of the phenol hydroxyl group and secondary amine of the synthesized $N_2O_2$ ligands were shown by four step wise values. The orders of the calculated overall proton dissociation constants ($log{\beta}_p$) were Br-3BPD < Cl-3BPD < H-3BPD in case of 3BPD and Br-2BPD < Cl-2BPD < H-2BPD in case of 2BPD respectively. The order agreed well with that of $para$ Hammett substituent constants(${\delta}_p$). The stability constants($logK_{ML}$) of the complexes between the synthesized ligands and transition metal(II) ions agreed with the order of $log{\beta}_p$ of the ligands. The order of the $logK_{ML}$ value of the each transition metal (II) ion was Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II), which agreed well with that of Iriving-Williams series.

Studies on Constituents of the Higher Fungi of Korea (LV) -The Antitumor Components and Culture of Lyophyllum decastes- (한국산(韓國産) 고등(高等) 균류(菌類)의 성분(成分) 및 배양(培養)에 관한 연구(硏究)(제55보)(第55報) -Lyophyllum decastes의 항암(抗癌) 성분(成分) 및 배양(培養)-)

  • Lee, Chong-Ock;Kim, Hyung-Soo;Choi, Eung-Chil;Kim, Byong-Kak
    • Korean Journal of Pharmacognosy
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    • v.17 no.1
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    • pp.23-34
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    • 1986
  • To find antitumor components of Lyophyllum decastes, the mycelia of L. decastes were cultured in artificial media and a new antitumor component which showed potent antitumor activity against sarcoma 180 implanted in mice, was isolated and named 'Lyophyllan A'. Lyophyllan A was composed of a polysaccharide moiety (86%) and a protein moiety (2%). The polysaccharide moiety was found to be a heteroglycan which consisted of glucose (48.1%), mannose (30.8%), galactose, xylose and fucose. The protein moiety contained 18 amino acids. Cultural characteristics of L. decastes were investigated by shake culture method. The best result was obtained when L. decastes was cultured in medium glucose 50g, peptone 10g, corn steep liquor 30ml, $KH_2PO_4$ 0.87g, $MgSO_4$ $7H_2O$ 0.5g, $CaCl_2$ 0.3g, $FeSO_4{\cdot}7H_2O$ 10mg, $MnCl_2{\cdot}4H_2O$ 7mg, $ZnSO_4{\cdot}7H_2O$ 4mg and $CuSO_4{\cdot}5H_2O$ 1mg per one liter at $26^{circ}C$, 180rpm, for 9 days.

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Studies on proteolytic enzyme from A New Strain in Serratia sp. (Serratia속의 신균주가 생산하는 단백질분해효소)

  • 최완수;정계종;이주경;박주웅;이상훈;이진복;이송락;최신원
    • YAKHAK HOEJI
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    • v.37 no.2
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    • pp.129-135
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    • 1993
  • Serratia sp. Y-4 was isolated from soil. Many characteristics of the strain and optimum cultivation condition for protease production were investigated.,The protease from Serratia sp. Y-4 was purified and studied for the properties of the enzyme. The isolated strain was identified to the genus Serratia. The strain was cultivated in 1%-casein, 0.5%-Na$_{3}$PO$_{4}$.7H$_{2}$O, 0.1%-NaCl, 0.05%-KCI, 0.02%-MgSO$_{4}$.7H$_{2}$O, 0.02%-CaCl$_{2}$.2H$_{2}$O, 0.02%-ZnSO$_{4}$.7H$_{2}$O, 0.02%-MnCl$_{2}$.4H$_{2}$O and 0.5%-soy bean oil at pH 7.0 for 35 hrs. The enzyme was purified about 5.89 fold from the culture broth with 31.1% recovery and 19,613 u/mg through ultrafiltration, ammonium sulfate, DEAE-sephacel and Superose-12 chromatography. The purified enzyme was identified as one band by isoelectric focusing, SDS- and native-PAGE. It has maxium activity at $37^{\circ}C$ and pH 9.0. Molecular weight of it is approx. 50 kD and pl is about 6.70. Its Km value for casein was 20 mg/ml. 5 mM-EDTA, 5mM-SDS, Ag$^{+1}$, Cu$^{+2}$, Hg$^{+2}$ and Pb$^{+2}$ inhibited the enzyme.

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A Study of Heavy Metal Contents in plants from Mt. Kwang-Duk Area (광덕산 식물체의 중금속 함량에 관한 연구)

  • 이기태;최한수
    • Environmental Analysis Health and Toxicology
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    • v.14 no.4
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    • pp.155-163
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    • 1999
  • Heavy metal accumulation in living organisms through food-wed can give serious damage on physiological responses for vital activities. The initiation of heavy metal supposed to begin from the bio-accumulation of plants. To establish basic data fur heavy metal contents in plants at the area without artificial contamination, both woody and herb plants at Mt. Kwang-Duk were studied. The content of heavy metals in various organs of plants were analyzed by ICP. The range of heavy metals in plants for Al, As, Cd, Co, Cr, Cu, Fe. Mn, Pb, Se and Zn were 1.019∼257.200ppm, O∼2.929ppm, 0∼0.079ppm, 0∼0.054ppm, 0.023∼3.007ppm, 0∼1.997ppm, 2.031∼148.500ppm, 1.069∼51.320ppm, O∼126.900ppm, 0.708∼4.927ppm and 0.846∼4.949ppm, respectively. The amount of heavy metals in plants are much less than that of soil except some species. In woody plants, it was detected that the metal contents of leaves were higher than that of stems especially in case of Al and Fe with statistical significance. There were significant differences between shoots and roots of herb plants in metal content of Al, Co and Fe. Those metals have more accumulated in roots comparing with shoots. Some species of plants had shown the difference tendency of heavy metal accumulation. Generally, most species had not exceeded over twice of mean value each other, and had various difference according to the kinds of heavy metals.

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