• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2351-2357
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• 2011

Three new metal-organic copper(II) complexes, $[Cu(H_2PZTC)_2]_n{\cdot}2nH_2O$ (1), $[Cu(HPZTC){\cdot}2H_2O]_n{\cdot}2nH_2O$ (2), and $Cu_2[(PZHD)(OH)(H_2O)_2]_n$ (3) ($H_3PZTC$ = pyrazine-2,3,5-tricarboxylic acid, $PZHD^{3-}$ = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from $Cu(II)/H_3PZTC$ system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, $H_3PZTC$ ligands loose one and two protons, which were transformed into $H_2PZTC^-$ anion and $HPZTC^{2-}$ dianion under different preparation condition, respectively. Furthermore, two ligands coordinate with Cu(II) cations in different modes, leading to the formation of the different chain structures. In complex 3, $H_3PZTC$ ligand was converted into a new ligand-PZHD by in situ decarboxylation and hydroxylation under a higher pH value than that for complexes 1 and 2. PZHD ligands link the Cu(II) cations to form a 2D layer structure. These results demonstrate that the preparation conditions, including pH value and reaction temperature etc, play an important role in the construction of complexes based on $H_3PZTC$ ligand.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.15-18
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• 2001

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(SOL)-D)$_3$] complexes were synthesized by the keto-enol tautomerism reaction of Yb(SOL-H)$_3$ in methanol-d$_4$in methanol-d$_4$in order to reduce the radiationless transition to the ligands. The luminescence properties of Yb(SOL-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$\sub$8/, PO(OCH$_3$)$_3$ and DMSO-d$\sub$6/. The intensity, lifetime and quantum efficiency of the luminescence in DMSO-d$\sub$6/ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$\sub$6/ might be the most appropriate solvent for the liquid laser material of Yb(SOL-D)$_3$ complex.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.640-643
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• 2001

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(SOL-D)$_3$] complexes were synthesized by the keto-enol tautomerism reaction of Yb(SOL-H)$_3$in methanol-d$_4$in order to reduce the radiationless transition to the ligands. The luminescence properties of Yb(SOL-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$_{8}$, PO(O$CH_3$)$_3$and DMSO-d$_{6}$. The intensity, lifetime and quantum efficiency of the luminescence in DMSO-d$_{6}$ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$_{6}$ might be the most appropriate solvent for the liquid laser material of Yb(SOL-D)$_3$complex.complex.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.12
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• pp.1045-1050
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• 2000

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(HFA-D)$_3$]complexes were synthesized by the keto-enol tautomerism reaction of Yb(HFA-H$_3$) in methanol-d$_4$in rder to reduct the radiationless transition to the ligands. The luminescence properties of Yb(HFA-D)$_3$complex were measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$_{8}$, PO(O$CH_3$)$_3$and DMSO-d$_{6}$. The intensity, lifetime and quantum efficiency of the luminescnce in DMSO-d$_{6}$ were superior to those in other deuterated solvents. It was suggested that the anhydrous DMSO-d$_{6}$ might be the most appropriate solvent for the liquid laser material of Yb(HFA-D)$_3$complex.complex.

• Environmental Analysis Health and Toxicology
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• v.13 no.1_2
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• pp.11-17
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• 1998

Cadmium, a major aquatic pollutant in many parts of the world, is toxic and readily accumulated in aquatic organisms. It mainly exists in water as complexes with organic ligands such as dissolved organic carbon and this complexation is known to have effects on the aquatic toxicities. In this study, acute toxicity, histology, and bioaccumulation were studied to evaluate effects of humic acid on cadmium toxicity and bioavailability to fish using Oryzias lalipes and Cyprinus carpio. 96h-LC$_{50}$ of cadmium was 6.38mg/L using Oryzias latipes. However, the mortality showed the dose-dependent decrease when humic acid was added to the test solution. When fish were exposed to 5 mg/L of cadmium, histological changes in the exposed organs (caudal fins, gills, kidney, liver, and gut) of C~lprinus carpio were decreased by humic acid, especially in kidney and liver. Bioaccumulation of cadmium also decreased by treatment of humic acid. It seems that the formation of complexes between cadmium and humic acid may decrease bioavailability of cadmium to fish, and thus reduce the toxic effects of cadmium.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.4
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• pp.376-386
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• 2015

MOFs(Metal-Organic Frameworks) are new kinds of materials comprised of metal ions and functional organic ligands, and have large pores in its rigid structures which give the materials various functionalities, including gas absorption, separation, drug delivery etc. Recently photoluminescence properties of MOFs and possibilities of its application to high explosive sensing technologies are drawing attentions from scientists and engineers, because these methods are simple, cheap and easy to perform detection operations. In this article the author reviews the mechanisms of photoluminescence of MOFs, the detection methods of high explosives using MOFs and recent research progresses based on the papers published mainly during last 10 years.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.4
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• pp.510-520
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• 2014

Metal-Organic Frameworks(MOFs) are attracting attentions from various fields including chemistry, materials science, physics and medical science because of its exceptionally large pore volumes and surface areas which far exceed those of zeolites. The possibilities of applications of MOFs for gas separation, catalysts, drug delivery, and high explosives detections have already been verified. In these review the author describes the structures, synthetic methods and applications of MOFs based on the literatures published during last 15 years to give the readers general pictures of MOF itself as well as the global research trends of these materials.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.11
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• pp.928-933
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• 2001

Perdeuterated hexaflouroacetylacetonato-ytterbium [Yb(SOL-D)$_3$] complexes are synthesized by the keto-enol tautomerism reaction of Yb(SOL-H)$_3$ in methanol-d$_4$ in order to reduce the radiationless transition to the ligands for the high power solid state laser material. The luminescence properties of Yb(SOL-D)$_3$ complex are measured in the following anhydrous deuterated organic solvents ; Methanol-d$_4$, THF-d$_{8}$, PO(O$CH_3$)$_3$ and DMSO-d$_{6}$. The Luminescence intensity, lifetime and quantum efficiency in DMSO-d$_{6}$ are superior to those in other deuterated solvents. It is suggested that the anhydrous DMSO-d$_{6}$ might be the most appropriate solvent for the laser material of Yb(SOL-D)$_3$ complex.complex.

• Journal of the Korean Ceramic Society
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• v.42 no.1
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• pp.50-55
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• 2005

New fast proton-conducting organic-inorganic nanocomposite membranes were successfully fabricated using polymer matrix obtained through proper oxidation of thiol ligands in (3-Mercaptopropyl) trimethoxysilane (MPTS) and hydrolysis/condensation reaction of (3-glycidoxypropyl) trimethoxysilane (GPTS). The obtained nanocomposite membranes showed relatively hirh proton-conductivity over $10^{-2}S/cm$ at $ 25^{circ}C$. The proton conductivities of the fabricated composite membranes increased up to $3.6{\times}10^{-1}$ S/cm cm by increasing temperature and relative humidity to $70^{circ}C$ and 100 $100RH\%$. The high proton conductivity of the composites Is due to the proton conducting path through the GPTS-derived 'pseudo-polyethylene oxide 'network in which sulfonic acid ligands work as a proton donor.

• Journal of Powder Materials
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• v.21 no.3
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• pp.179-184
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• 2014

In this study, we prepare polymer solar cells incorporating organic ligand-modified Ag nanoparticles (O-AgNPs) highly dispersed in the P3HT:PCBM layer. Ag nanoparticles decorated with water-dispersible ligands (WAgNPs) were also utilized as a control sample. The existence of the ligands on the Ag surface was confirmed by FT-IR spectra. Metal nanoparticles with different surface chemistries exhibited different dispersion tendencies. O-AgNPs were highly dispersed even at high concentrations, whereas W-AgNPs exhibited significant aggregation in the polymer layer. Both dispersion and blending concentration of the Ag nanoparticles in P3HT:PCBM matrix had critical effects on the device performance as well as light absorption. The significant changes in short-circuit current density ($J_{SC}$) of the solar cells seemed to be related to the change in the polymer morphology according to the concentration of AgNPs introduced. These findings suggested the importance of uniform dispersion of plasmonic metal nanoparticles and their blending concentration conditions in order to boost the solar cell performance.