• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3749-3754
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• 2013

Two 3D isomorphous and isostructural complexes, namely, $[Zn(BDOA)(bpy)(H_2O)_2]_n$ (1) and $[Cd(BDOA)-(bpy)(H_2O)_2]_n$ (2); (BDOA = Benzene-1,4-dioxyacetic acid, bpy = 4,4'-bipyridine) were synthesized under hydrothermal conditions and characterized by means of elemental analyses, thermogravimetric (TG), infrared spectrometry, and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in the triclinic system, space group P-1 and each metal ion in the complexes are six-coordinated with the same coordination environment. In the as-synthesized complexes, $BDOA^{2-}$ anions link central metal ions to form a 1D zigzag chain $[-BDOA^{2-}-Zn(Cd)-BDOA^{2-}-Zn(Cd)-]_{\infty}$, whereas bpy pillars connect metal ions to generate a 1D linear chain $[-bpy-Zn(Cd)-bpy-Zn(Cd)-]_{\infty}$. Both infinite chains are interweaved into 2D grid-like layers which are further constructed into a 3D open framework, where hydrogen bonds play as the bridges between the adjacent 2D layers. Luminescent properties of complex 1 showed selectivity for $Hg^{2+}$ ion.

• Journal of Sensor Science and Technology
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• v.15 no.5
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• pp.323-327
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• 2006

Manganese, copper and chlorine-doped ZnS phosphors (ZnS:Mn,Cu,Cl) were synthesized through solid-state reaction. Manganese was added in the range of amount $1.4{\sim}5.3$ mol % to ZnS phosphors containing 0.2 or 1.0 mol % of copper and a small amount of chlorine. As-synthesized phosphors showed a spherical morphology with a mean size of ${\sim}20\;{\mu}m$ and structural properties of Wurtzite, which were identified by SEM and XRD, respectively. Optical properties of ZnS:Mn,Cu,Cl synthesized with various concentrations of activators were analysed by both of PL and EL spectra. Samples mainly showing only 580 nm-orange emission by 380 nm-UV excitation gave different EL spectra of blue, green, and orange emissions at 450, 480 and 580 nm, respectively, depending on concentrations of $Cu^{2+}$ and $Mn^{2+}$.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.163-170
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• 2022

This study investigates the effects of the dietary inclusion of zinc oxide (ZnO) on the growth performance, apparent total digestibility, and the fecal scores of growing pigs fed a corn-wheat-based diet. In total, 84 crossbred (Landrace × Yorkshire × Duroc) growing pigs with an initial body weight of (20.86 ± 0.64 kg) (4 pigs·pen^-1; 2 gilts and 2 barrows; 7 replications·treatment^-1) were randomly assigned to three treatment groups based on body weight (BW) and sex in a three-week trial. The dietary treatments were as follows: TRT1 (CON [basal diet]), TRT2 (CON + 0.07% ZnO), and TRT3 (CON + 1% ZnO). Dietary ZnO supplementation significantly (p < 0.05) improved body weight gain (BWG) of growing pigs at weeks 2 and 3 compared to the control diet. In addition, dietary ZnO supplementation significantly (p < 0.05) increased the average daily gain (ADG) and average daily feed intake (ADFI) at weeks 2, 3, and overall. However, the feed conversion ratio (FCR) remained unaffected throughout the trial. Regarding the total tract nutrient digestibility of nitrogen, dry matter was significantly improved with an increased level of ZnO supplementation. In addition, dietary supplementation of ZnO significantly reduced fecal scores in grower pigs at the initial period compared to the control diet. In summary, dietary inclusion of zinc oxide via supplementation improved growth performance, and total tract digestibility and reduced the fecal scores of growing pigs.

• Journal of the Korean institute of surface engineering
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• v.53 no.3
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• pp.104-108
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• 2020

ZnO single layer films (100 nm thick) and Au intermediated ZnO films (ZnO/Au/ZnO; ZAZ) were deposited on the glass substrate by RF and DC magnetron sputtering at room temperature and then the influence of the Au interlayer on the electrical and optical properties of the films were investigated. ZnO thin films show the visible transmittance of 90.3 % and sheet resistance of 63.2×10⁸ Ω/□. In ZAZ films, as Au interlayer thickness increased from 6 to 10 nm, the sheet resistance decreased from 58.3×10⁸ to 48.6 Ω/□, and the visible transmittance decreased from 84.2 to 73.9 %. From the observed results, it can be concluded that the intermediate Au thin film enhances the opto-electrical performance of ZnO films without intentional substrate heating.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.87-91
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• 2013

The crystal structure of partially dehydrated fully $Zn^{2+}$-exchanged zeolite Y was determined by X-ray diffraction techniques in the cubic space group $Fd\bar{3}m$ at 294(1) K and refined to the final error indices $R_1/wR_2$ = 0.035/0.119 for $|Zn_{35.5}(H_2O)_{13}|[Si_{121}Al_{71}O_{384}]$-FAU. About 35.5 $Zn^{2+}$ ions per unit cell are found at six distinct positions; sites I, I', a second I', II', II, and a second II. In sodalite cavities, the 11 water molecules coordinate to Zn(I'b) and/or Zn(II') ions; each of two $H_2O$ bonds to a Zn(IIb) in supercages. Two different $Zn^{2+}$ positions near 6-oxygen ring are due to their Si-Al ordering in tetrahedral site by Si/Al ratio leading to the different kinds of 6-rings.

• Journal of Electrochemical Science and Technology
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• v.14 no.2
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• pp.162-173
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• 2023

Aqueous zinc-ion batteries are considered as promising alternatives to lithium-ion batteries for energy storage owing to their safety and cost efficiency. However, their lifespan is limited by the irreversibility of Zn anodes because of Zn dendrite growth and side reactions such as the hydrogen evolution reaction and corrosion during cycling. Herein, we present a strategy to restrict direct contact between the Zn anode and aqueous electrolyte by fabricating a protective layer on the surface of Zn foil via phosphidation method. The Zn₃(PO₄)₂ protective layer effectively suppresses Zn dendrite growth and side reactions in aqueous electrolytes. The electrochemical properties of the Zn₃(PO₄)₂@Zn anode, such as the overpotential, linear polarization resistance, and hydrogen generation reaction, indicate that the protective layer can suppress interfacial corrosion and improve the electrochemical stability compared to that of bare Zn by preventing direct contact between the electrolyte and the active sites of Zn. Remarkably, MnO₂ Zn₃(PO₄)₂@Zn exhibited enhanced reversibility owing to the formation a stable porous layer, which effectively inhibited vertical dendrite growth by inducing the uniform plating of Zn²⁺ ions underneath the formed layer.

• Mass Spectrometry Letters
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• v.3 no.3
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• pp.82-85
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• 2012

The formation of zinc finger peptide-$Zn^{2+}$ complexes in electrospray ionization mass spectrometry (ESI-MS) was examined using three different metal ion sources: $ZnCl_2$, $Zn(CH_3COO)_2$, and $Zn(OOC(CHOH)_2COO)$. For the four zinc finger peptides (Sp1-1, Sp1-3, CF2II-4, and CF2II-6) that bind only a single $Zn^{2+}$ in the native condition, electrospray of apo-zinc finger in solution containing $ZnCl_2$ or $Zn(CH_3COO)_2$ resulted in the formation of zinc finger-$Zn^{2+}$ complexes with multiple zinc ions. This result suggests the formation of nonspecific zinc finger-$Zn^{2+}$ complexes. Zn(tartrate), $Zn(OOC(CHOH)_2COO)$, mainly produced specific zinc finger-$Zn^{2+}$ complexes with a single zinc ion. This study clearly indicates that tartrate is an excellent counter ion in ESI-MS studies of zinc finger-$Zn^{2+}$ complexes, which prevents the formation of nonspecific zinc finger-$Zn^{2+}$ complexes.

• Transactions on Electrical and Electronic Materials
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• v.4 no.6
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• pp.13-16
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• 2003

Mn-doped $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film phosphors have been grown using a pulsed laser deposition technique under various growth conditions. The structural characterization carr~ed out on a series of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) films grown on MgO(l00) substrates usmg Zn-rich ceramic targets. Oxygen pressure was varied from 50 to 200 mTorr and Zn/Ga ratio was the function of oxygen pressure. XRD patterns showed that the lattice constants of the $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film decrease with the substitution of sulfur and selenium for the oxygen in the $ZnGa_2O_4$. Measurements of photoluminescence (PL) properties of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin films have indicated that MgO(100) is one of the most promised substrates for the growth of high quality $ZnGa_2O_{4-x}M_{x}$:$Mn^{2+}$ (M=S, Se) thin films. In particular, the incorporation of Sulfur or Selenium into $ZnGa_2O_4$ lattice could induce a remarkable increase in the intensity of PL. The increasing of green emission intensity was observed with $ZnGa_2O_{3.925}Se_{0.075}:$Mn^{2+}$ and $ZnGa_2O_{3.925}S_{0.05}$:$Mn^{2+}$ films, whose brightness was increased by a factor of 3.1 and 1.4 in comparison with that of $ZnGa_{2}O_{4}$:$Mn^{2+}$ films, respectively. These phosphors may promise for application to the flat panel displays.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.717-726
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• 2022

This study was conducted to assess the geochemical contamination degree of As, Cd, Cu, Pb, Sb, and Zn in the soil and water samples from an abandoned gold mine. Enrichment Factor (EF), Geoaccumulation Index (Igeo), and Pollution Load Index (PLI) were carried out to assess the geochemical contamination degree of the soil samples. Variations of sulfate and heavy metals concentration in water samples were determined to identify the geochemical distribution with respect to the distance from the mine tailing dam. Geochemical pollution indices indicated significant contaminated with As, Cd, Pb, and Zn in the soil samples that areas close to the mine tailing dam, while, Sb showed similar indices in all soil samples. These results indicated that the As, Cd, Pb, and Zn dispersion has occurred via anthropogenic sources, such as mining activities. In terms of water samples, anomalies in the concentrations of As, Cd, Zn, and SO₄^2- was determined at specific area, in addition, the concentrations of the elements gradually decreased with distance. This result implies the heavy metals distribution in water has carried out by the weathering of sulfide minerals in the mine tailing and soil. The study area has been conducted the remediation of contaminated soil in the past, however, the geochemical dispersion of heavy metals was supposed to be occurred from the potential contamination source. Therefore, continuous monitoring of the soil and water is necessary after the completion of remediation.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.151-151
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• 2019