• Title/Summary/Keyword: CuInS2

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Heavy Metals in Sediments and Burrowing Bivalves (Sinonovacula constricta Lamarck) from Tidal Flats along the Saemankeum Area, Korea (새만금지역 갯벌 환경(패류, 저질)에서의 중금속 분포특성)

  • Hwang, Gab-Soo;Shin, Hyung-Seon;Kim, Kangjoo;Yeo, Sung-Koo;Park, Seongmin;Lim, Kyujae
    • Journal of Korean Society on Water Environment
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    • v.18 no.4
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    • pp.341-354
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    • 2002
  • Heavy metal concentration/distribution in sediments and bivalves from the tidal flats in Saemankeum coastal area, western Korea, were investigated, Among 6 sampling sites, S2, S5 and S6 showed the higher levels of Zn, Cr, Ni, Cu and Cd contamination and S1 did the higher level of Pb contamination than other sites, while S-4 showed the lowest levels of these metal contamination. Overally, the levels of Zn, Cu and Pb concentrations in Sinonovacula constricta were estimated to be relatively high. The shell lengths of the collected mussels were linearly related to their dry weights of the whole soft parts, but the mussels collected from S3 were in a poor nutrition, resulting in the distinctively high levels of metal concentrations in the body. It was shown that in S. constricta, Cr, Ni, Cu and Zn are distributed equally into the whole soft parts or a little more into the flesh, after absorption, while Fe, Cd, Pb and Mn are transferred more into the non-flesh parts than into the flesh parts. In S. constricta, the heavy metal concentrations in the flesh increase with those in the whole soft parts. The bioaccumulation factors(heavy metal concentration in S. constricta/heavy metal concentration in sediment) showed that, of the examined metals, Cd is the most cumulative in the body of S. constricta, followed by Zn and Cu, while Mn, Cr, Ni and Pb are not cumulative.

Sensitivity of BOD Sensor with Heavy Metal Tolerant Serratia marcescens LSY4 (Serratia marcescens LSY4 중금속 내성주를 이용한 BOD센서의 감응도)

  • Kim Mal-Nam;Lee Sun-Young
    • Korean Journal of Environmental Biology
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    • v.22 no.3
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    • pp.394-399
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    • 2004
  • A BOD sensor was prepared with S. marcescens LSY4 and was applied for measurement of BOD values of a solution containing the standard organic pollutants. The sensor sensitivity was nearly independent of the culture time in the range of 9-16 hours. It was also affected little by the cell mass in the range of 0.22-0.75 mg $cm^{-2}$. A cyclic change in the solution pH in the range of 4-9 was accompanied by a reversible variation in the sensor sensitivity. However, the reversibility was lost when the solution pH became more acidic or more basic. Heavy metal ions lowered the sensor sensitivity, which took place more precipitously in the presence of $Cu^{2+}$ and $Ag^+$ rather than in the presence of $Zn^{2+}$ and $Cd^{2+}$. The reduction of the sensor sensitivity was significantly attenuated by loading heavy metal ion tolerance induced strain. The $Cu^{2+}$tolerance induced strain was more efficient for the attenuation than $Zn^{2+}$ and $Cd^{2+}$ tolerance induced strain.

Charge Redistribution of Pt-based Alloys

  • Lim, K.Y.;Chung, Y.D.;Kwon, S.Y.;Lee, Y.S.;C.N.Whang;Y.Jeon;Park, B.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.171-171
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    • 1999
  • We studied the charge redistribution in the Pt-M (M=Cu, Co) alloys by X-ray Absorption Near Edge Spectroscopy(XANES) and X-ray Photoelectron Spectroscopy(XPS). These analysis tools provide us information about the charge transfer in the valence band of intermetallic bonding. The samples were prepared by arc-melting method. After annealing this samples in vacuum for several hours, we cold get the ordered samples, which were confirmed with XRD analysis. the core and valence level energy shift in these system were investigated by Mg $K\alpha$(1253.6eV) x-ray source for Pt-Co alloys and monochromatized Al $K\alpha$ (1486.6eV) for Pt-Cu alloys. Pt L2, L3-edge, and Cu, Co K-edge XANES spectra were measured with the total electron-yield mode detector at the 3Cl beam line of the PLS (Pohang light source0. from the changes of White line (WL) area and the core level shifts of the each metal sites, we can obtain the information about the electrons participating in the intermetallic bonding of the Pt-Cu and Pt-Co alloys.

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Influence of Dislocation Substructure on Ultrasonic Velocity under Tensile Deformation

  • Kim, C.S.;Lissenden, Cliff J.;Kang, Kae-Myhung;Park, Ik-Keun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.28 no.6
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    • pp.477-482
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    • 2008
  • The influence of dislocation substructure of metallic materials on ultrasonic velocity has been experimentally investigated. The test materials of pure Cu, brass (Cu-35Zn), 2.25Cr-1Mo steel, and AISI 316 with different stacking fault energy (SFE) are plastically deformed in order to generate dislocation substructures. The longitudinal wave velocit $(C_L)$ decreases as a function of tensile strain in each material. The $C_L$ of Cu-35Zn and AISI 316 decreases monotonously with tensile strain, but $C_L$ of Cu and 2.25Cr-1Mo steel shows plateau phenomena due to the stable dislocation substructure. The variation of ultrasonic velocity with the extent of dislocation damping and dislocation substructures is discussed.

Estimation of the Prosthetic Group of Laccase Secreted from Pleurotus ostreatus (Pleurotus ostreatus에서 분비된 Laccase의 보결단 추정)

  • 윤홍덕;신광수;강사욱;하영칠;정가진;김규중
    • Korean Journal of Microbiology
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    • v.29 no.4
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    • pp.238-242
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    • 1991
  • Extracellular laccase secreted from Pleurotus ostreatus was activated by $Cu^{2+}$ and $Cu^{+}$ . The enzyme was strongly inactivated by 8-hydroxyquinoline, potassium cyanide, sodium azide, sodium bisulfite and 2-mercaptoethanol. The two ionogenic groups, which have pKa values of 5.60-5.70 and 6.70-6.85 respectively, were found to relate with the active site of this enzyme. The oxidation reactions were brought about by initial single electron transfer process on the active site. The enzyme was found to be a metalloprotein which had about 3.9 cupric ions per molecule of protein as a prosthetic group. The enzyme showed a strong peak at 605 nm and a weak shoulder at 330 nm in UV-Visible absorption spectrum. Both signals disappeated upon treatment of the enzyme with 4 electron equivalent ascorbate. These results indicate that type I Cu peak and type III Cu shoulder are present in laccase.

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A study of joint properties of Sn-Cu-(X)Al(Si) middle-temperature solder for automotive electronics modules (자동차 전장부품을 위한 Sn-0.5Cu-(X)Al(Si) 중온 솔더의 접합특성 연구)

  • Yu, Dong-Yurl;Ko, Yong-Ho;Bang, Junghwan;Lee, Chang-Woo
    • Journal of Welding and Joining
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    • v.33 no.3
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    • pp.19-24
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    • 2015
  • Joint properties of electric control unit (ECU) module using Sn-Cu-(X)Al(Si) lead-free solder alloy were investigated for automotive electronics module. In this study, Sn-0.5Cu-0.01Al(Si) and Sn-0.5Cu-0.03Al(Si) (wt.%) lead-free alloys were fabricated as bar type by doped various weight percentages (0.01 and 0.03 wt.%) of Al(Si) alloy to Sn-0.5Cu. After fabrications of lead-free alloys, the ball-type solder alloys with a diameter of 450 um were made by rolling and punching. The melting temperatures of 0.01Al(Si) and 0.03Al(Si) were 230.2 and $230.8^{\circ}C$, respectively. To evaluation of properties of solder joint, test printed circuit board (PCB) finished with organic solderability perseveration (OSP) on Cu pad. The ball-type solders were attached to test PCB with flux and reflowed for formation of solder joint. The maximum temperature of reflow was $260^{\circ}C$ for 50s above melting temperature. And then, we measured spreadability and shear strength of two Al(Si) solder materials compared to Sn-0.7Cu solder material used in industry. And also, microstructures in solder and intermetallic compounds (IMCs) were observed. Moreover, thickness and grain size of $Cu_6Sn_5$ IMC were measured and then compared with Sn-0.7Cu. With increasing the amounts of Al(Si), the $Cu_6Sn_5$ thickness was decreased. These results show the addition of Al(Si) could suppress IMC growth and improve the reliability of solder joint.

Study on the production of porous CuO/MnO2 using the mix proportioning method and their properties (반응몰비에 따른 다공성 CuO/MnO2의 제조 및 특성 연구)

  • Kim, W.G.;Woo, D.S.;Cho, N.J.;Kim, Y.O.;Lee, H.S.
    • Analytical Science and Technology
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    • v.28 no.3
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    • pp.182-186
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    • 2015
  • In this study, the porous CuO/MnO2 catalyst was prepared through the co-precipitation process from an aqueous solution of potassium permanganate (KMnO4), manganese(II) acetate (Mn(CH3COO)2·4H2O) and copper(II) acetate (Cu(CH3COO)2·H2O). The phase change in MnO2 was analyzed according to the reaction molar ratio of KMnO4 to Mn(CH3COO)2. The reaction mole ratio of KMnO4 to Mn(CH3COO)2·4H2O was varied at 0.3:1, 0.6:1, and 1:1. The aqueous solution of Cu(CH3COO)2 was injected into a mixed solution of KMnO4 and Mn(CH3COO)2 to 10~75 wt% relative to MnO2. The Cu ion co-precipitates as CuO with MnO2 in a highly dispersed state on MnO2. The physicochemical property of the prepared CuO/MnO2 was analyzed by using the TGA, DSC, XRD, SEM, and BET. The different phase types of MnO2 were prepared according to the reaction mole ratio of KMnO4 to Mn(CH3COO)2·4H2O. The results confirmed that the porous CuO/MnO2 catalyst with γ-phase MnO2 was produced in the reaction mole ratio of KMnO4 to Mn(CH3COO)2 as 0.6:1 at room temperature.

Electrical properties of CuInSe2 thin films formed by selenization of RF sputtered Cu-In-Se2 precursors for solar cell applications (Cu-In-Se2 전구체의 Selenization에 의해 형성된 CuInSe2 박막의 태양전지 응용을 위한 전기적 특성평가)

  • Jeong, Chaehwan;Park, Chanyoung;Kim, Jinhyeok;Lee, Suk Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.79-79
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    • 2010
  • 다른 물질에 비해 많은 우수한 특성을 가지고 있는 CuInSe2(CIS)박막 태양전지는 많은 연구자들에 의해 개발되어 오고 있다. CIS의 대표적인 장점으로는 직접천이형 밴드갭, 높은 흡수계수, 열 안정화상태 및 p형으로의 전도성물질의 가능성 등 다양하다. 또한 간단한 구조를 이용하여 유리같은 싼 기판을 이용하기 때문에 저가형 태양전지로서 많은 각광을 받고 있다. CIGS태양전지는 CIS의 In 사이트에 Ga을 도핑함으로서 만들어지는데 밴드갭은 약 1.4eV이다. CIS박막을 만드는 많은 방법이 존재하나 구성원소로부터 최적화된 조성을 찾을수 있는 방법이 가장 중요한 요소 중의 하나로 인식되고 있으며, 이런점에서 증발법 및 스퍼터링법 등 같은 진공방식이 비진공방식에 비해 훨씬 간편하게 조성비를 맞출수 있다. 그 중에 스퍼터링법은 대면적 박막태양전지로의 가능성으로 비출어 볼때 산업화를 위한 좋은 후보군이 될 수 있다. Selenization을 하기전에 Cu-In-Se의 전구체 조합은 여러개의 타겟으로부터 동시 스퍼터링법이나 다층 전구체법을 사용하여 준비되는데 어떤 방법이 되던지 Se의 부가적인 공급은 불가피하다. 지금까지 많은 관련 연구의 대부분인 구조적, 조성비적 그리고 광학적인 특성평가에 집중되어 오고 있는데, 전기적특성평가의 경우는 면저항, 비저항 같은 간단한 결과 위주로 보고되어 오고 있다. 또한 캐리어농도와 이동도에 대한 보고가 있음에도 불구하고 이해되기에는 충분치 못한 면이 많다.본 발표에서는 태양전지 제조 전단계로서 소다라임유리기판(SLG)위에 Mo의 유무에 따라 CIS박막의 전기적인 특성 변화에 대한 내용을 담고 있다. 소다라임유리($2cm{\times}2cm$)를 기판으로 사용하여 아세톤-에탄올 용액에 초음파세척을 수행하고, Mo 후면전극을 DC 스퍼터링방식을 이용하여 증착을 한다. SLG와 Mo이 코팅된 SLG를 각각 RF 스퍼터 챔버에 이송한 후 수증기 제거를 위해 약 10분간 예열을 한다. 샘플에 대한 전기적특성은 Hall효과 측정장치에 의해 측정이 되며 전기전도도, 캐리어농도, 이동도 및 전도형에 대한 정보가 각각의 변수에 따라 조사된돠. 부가적으로 구조적, 조성비적인 특성을 SEM,XRD 및 EDX를 통해 조사를 하여 전기적 특성에 따른 관계성을 검토한다. SLG와 Mo가 코팅된 SLG위의 CIS박막은 전기적으로 약간 다른 특성을 보일 것으로 예측되며, 이러한 기대를 바탕으로 조성비가 이상적인 화학양론에 근접할 때 p형으로서 제시될 수 있다는 것을 보여줄 것이다.

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Determination of Arsenic in Korean human liver and manganese, copper in Vitamin prepartions by neutron action analysis (중성자(中性子) 방사화(放射化) 분석법(分析法)에 의(依)한 한국인(韓國人) 간장중(肝臟中)의 비소(砒素) 및 Vitamin제제중(製劑中)의 금속(金屬)(CU, Mn)의 정량(定量))

  • Oh, Soo-Chang
    • Journal of Pharmaceutical Investigation
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    • v.4 no.4
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    • pp.17-25
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    • 1974
  • 1. Neutron acivation analysis of arsenic contained in Korean human liver was studied in the view point of forensic chemistry, using 12 corpses. A sample of 1g was irradiated for 30 mins. in a neutron flux of $1.2{\times}10^{12}n/cm^2/sec$, followed by nitric-sulfuric acid digestion and then by Gutzeit separation. Radio activity was detected by it's scintillation counter. The arsenic content in the liver was found to be $0.01{\mu}g/g$ to $0.15{\mu}g/g$. 2. A rapid and convenient method for the radiochemical determination of minerals by neutron activation analysis was established. After neutron irradiation to the standard soln. of Cu and Mn in pneumatic tube (neutron flux : $1.2{\times}10^{12}n/cm^2/sec$), Cu and Mn were determined by estimating the ratio of the widths under energy peak area in ${\gamma}-ray-spectrogram$. When the standard soln. of Mn and Cu is irradiated for 15 mins. to 18 hrs., recovery test shows that the relative errors are 5.1% and 4.5% for copper and manganese, respectively.

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Characterization of $Cu(In_xGa_{1-x})Se_2$ Solar Cells with Ga Content (Ga 함량에 따른 $Cu(In_xGa_{1-x})Se_2$ 태양전지의 특성분석)

  • Kim, Seok-Ki;Kwon, Se-Han;Lee, Doo-Yeol;Lee, Jeong-Churl;Kang, Ki-Whan;Yoon, Kyung-Hoon;Ahn, Byung-Tae;Song, Jin-Soo
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1264-1267
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    • 1998
  • $Cu(In_xGa_{1-x})Se_2$ thin films were prepared and characterized with various Ga contents. As the Ga content increased, the grain size of CIGS film became smaller. The 2 $\theta$ values in XRD patterns were shifted to larger values and the overlapped peaks were splitted. The energy bandgap increased from 1.04 to 1.67 eV and the resistivity decreased. The solar cell fabricated with ZnO/CdS/$Cu(In_{0.7}Ga_{0.3})Se_2/Mo$ structure yielded an efficeincy of 14.48% with an acitive area of 0.18 $cm^2$. The efficiency decreased with further increase of Ga content.

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