• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.35.1-35.1
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• 2010

The Cu(In,Ga)Se2(CIGS) thin film solar cells have been achieved until almost 20% efficiency by NREL. These solar cells include chemically deposited CdS as buffer layer between CIGS absorber layer and ZnO window layer. Although CIGS solar cells with CdS buffer layer show excellent performance, many groups made hard efforts to overcome its disadvantages in terms of high absorption of short wavelength, Cd hazardous element. Among Cd-free candidate materials, the CIGS thin film solar cells with Zn compound buffer layer seem to be promising with 15.2%(module by showa shell K.K.), 18.6%(small area by NREL). However, few groups were successful to report high-efficiency CIGS solar cells with Zn compound buffer layer, compared to be known how to fabricate these solar cells. Each group's chemical bah deposition (CBD) condition is seriously different. It may mean that it is not fully understood to grow high quality Zn compound thin film on the CIGS using CBD. In this study, we focused to clarify growth mechanism of chemically deposited Zn compound thin film on the CIGS, especially. Additionally, we tried to characterize junction properties with unfavorable issues, that is, slow growth rate, imperfect film coverage and minimize these issues. Early works reported that film deposition rate increased with reagent concentration and film covered whole rough CIGS surface. But they did not mention well how film growth of zinc compound evolves homogeneously or heterogeneously and what kinds of defects exist within film that can cause low solar performance. We observed sufficient correlation between growth quality and concentration of NH3 as complex agent. When NH3 concentration increased, thickness of zinc compound increased with dominant heterogeneous growth for high quality film. But the large amounts of NH3 in the solution made many particles of zinc hydroxide due to hydroxide ions. The zinc hydroxides bonded weakly to the CIGS surface have been removed at rinsing after CBD.

• Proceedings of the Korea Crystallographic Association Conference
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• 2005.11a
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• pp.10-10
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• 2005

• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.135-137
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• 1998

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2019-2029
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• 2016

Zinc finger proteins are among the most extensively applied metalloproteins in the field of biotechnology owing to their unique structural and functional aspects as transcriptional and translational regulators. The classical zinc fingers are the largest family of zinc proteins and they provide critical roles in physiological systems from prokaryotes to eukaryotes. Two cysteine and two histidine residues ($Cys_2His_2$) coordinate to the zinc ion for the structural functions to generate a ${\beta}{\beta}{\alpha}$ fold, and this secondary structure supports specific interactions with their binding partners, including DNA, RNA, lipids, proteins, and small molecules. In this account, the structural similarity and differences of well-known $Cys_2His_2$-type zinc fingers such as zinc interaction factor 268 (ZIF268), transcription factor IIIA (TFIIIA), GAGA, and Ros will be explained. These proteins perform their specific roles in species from archaea to eukaryotes and they show significant structural similarity; however, their aligned amino acids present low sequence homology. These zinc finger proteins have different numbers of domains for their structural roles to maintain biological progress through transcriptional regulations from exogenous stresses. The superimposed structures of these finger domains provide interesting details when these fingers are applied to specific gene binding and editing. The structural information in this study will aid in the selection of unique types of zinc finger applications in vivo and in vitro approaches, because biophysical backgrounds including complex structures and binding affinities aid in the protein design area.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2069-2072
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• 2010

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1743-1746
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• 2010

• Journal of the Korean institute of surface engineering
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• v.36 no.3
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• pp.272-283
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• 2003

Mild steel and zinc specimens were tested in five atmospheric testing sites of Vietnam in order to collect the corrosion databank as well as to study the corrosion mechanism in tropical conditions, in period of 1997-2000. The results obtained showed that the corrosion rate of steel is in the range of $10-50\;{\mu}m/year$ and of zinc is of $1-5\;{\mu}m/year$. They are interpretable in the comparison with the data obtained in different countries in the South East Asian as well as previous reports of Vietnamese nation project In atmospheric corrosion. The main factors affecting the corrosion in Vietnam tropical conditions are TOW (time of wetness) and salinity. The relationship between sulfur dioxide and corrosion of metals, particularly, zinc was not found clearly. An explanation was suggested about the complex effect of different pieces present in tropical atmosphere and about the alternative of the dominant factors such as humidity, salinity or temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.733-737
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• 2006

In this paper, we report the coordination state and structure of $Zn(cyclam)Cl_{2})$ complex that was studied by the Raman spectrum and conductivity method. The complex of zinc(II) ion with 1,4,8,11-tetraazacyclotetradecane(cyclam) ligand is formed in aqueous solution. According to the Raman spectrum of $Zn(cyclam)Cl_{2})$ complex, $H_{2}O$ molecule and $Cl^{-}$ ion compete for the trans coordination site of zinc(II) ion. We also have investigated the competition effect of $H_{2}O$ molecule and $Cl^{-}$ ion by the conductivity method. On addition of 1,4,8,11-tetraazacyclotetradecane(cyclam) ligand to the aqueous $ZnCl_{2}$ solution, 2: 1 electrolyte is changed to 1:1 electrolyte. We suggest the possibility of elimination of heavy metal because of the affinity effect of macrocyclic polyamine(1,4,8.11-tetraazacyclotetradecane) for the heavy metal,.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3743-3748
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• 2013

A tetradentate ligand of 2-phenyl-4,6-di(pyridin-2-yl)pyrimidine (L) has been synthesized and its complexes with $ZnI_2$ and CuI have been obtained by hydrothermal method. single crystal X-ray diffraction analysis indicates that ligand L coordinates with Zn(II) ions to form a simple four-coordinate di-nuclear complex, while the complexation of L with Cu(I) constructs a one-dimensional chain polymer. The existence of $I^-$ ion hampers the L to assemble grid-type complexes with Zn(II) and Cu(I). Fluorescence spectra show that the L emits blue fluorescence while its Cu(I) polymer decrease the fluorescence intensity and Zn(II) complex quenches the fluorescence.

• Journal of the Korean institute of surface engineering
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• v.38 no.1
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• pp.37-43
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• 2005

Nanosized titanium-colloid particles were prepared by sol-gel method. The physical properties, such as thermal stability, crystallite size and crystallinity according to synthesis condition have been investigated by TEM, XRD, SEM, TGA and DTA. In addition, Zinc phosphating has been studied in order to compare the phosphating characterization of prepared nanosized titanium-colloid particles. The major phase of all the prepared titanium-colloid particles was an amorphous structure regardless of synthesis temperature and the structure was composed of phoshate complex and titanium. The micrographs of HR- TEM showed that nanosized titanium-colloid particles possessed a spherical morphology with a narrow size distribution. The crystallite size of the titanium-colloid particles synthesized at 80℃ was 4-5 nm and increased to 8-10 nm with an increase of synthesis temperature (150℃). In addition, the coating weight increased with an increase of temperature of phosphating solution and when the concentration of titanium-colloid was 2.0 g/l, the coating weight was 1.0 g/㎡.