• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.703-708
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• 2009

In this paper, synthesis here Mn add to Ar any a vacuum an atomosphere $ZnGa_2O_4$ : Mn, ZnO and $Ga_2O_3$ power of 1:1 mole ratio mixture. Manufacture a close examination of oxygen a component variation luminescence a specific character reach an in fluence of $ZnGa_2O_4$ : Mn, luminescence spectrum, the surface a picture and a component ratio measurement, also an explanation of Mn site symmetry and at luminescence spectrum reach an influence from low temperature photoluminescence spectrum.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.10-16
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• 2010

In this paper, synthesis here Mn add to Ar injection the state and a vacuum an atomosphere $ZnGa_2O_4$ : Mn, ZnO and $Ga_2O_3$ power of 1 : 1 mole ratio mixture. Manufacture a close examination of oxygen a component variation luminescence a specific character reach an in fluence of $ZnGa_2O_4$ : Mn, luminescence spectrum observation also an explanation of Mn site symmetry and at luminescence spectrum reach an influence from low temperature photoluminescence spectrum.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.3
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• pp.96-101
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• 2001

In this study, diluted magnetic $Zn_{1-x}Mn_{x}Te$ epilayers were grown on GaAs(100) substrates by hot-wall epitaxy, and their characteristics were systematically examined. The maximum Mn composition of the $Zn_{1-x}Mn_{x}Te$ epilayers was 0.97. The crystallographic orientation was toward <100> and the structure of the $Zn_{1-x}Mn_{x}Te$ epilayers was the zincblende structure, identical to those of the GaAs substrate. With increasing the substrate temperature (350~$400^{\circ}C$), Mn composition increased (0.02~0.23) and he quality of the epilayer became worse. The lattice constants increased linearly with increasing Mn composition, but the band gap energy increased nonlinearly with increasing x.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.8
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• pp.627-631
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• 2010

ZnS:Mn yellow phosphors doped with Cu for white light emitting diodes were synthesized by solid state reaction method. The optical properties and structures of ZnS:Mn,Cu phosphors were investigated by x-ray diffraction, photoluminescence, and scanning electro microscopy. Photoluminescence excitation spectra originated from $Mn^{2+}$ were ranged from 450 nm to 500 nm. The yellow emission at around 580 nm was associated with $^4T_1{\rightarrow}^6A_1$ transition of $Mn^{2+}$ ions in ZnS:Mn,Cu phosphors. The highest photoluminescence intensity of the phosphors under 405 nm excitation was obtained at Cu concentration of 0.02 mol%. The enhanced photoluminescent intensity in the ZnS:Mn,Cu phosphors was interpreted by energy transfer from Cu to Mn.

• Journal of the Korean Institute of Navigation
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• v.25 no.4
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• pp.435-442
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• 2001

A new technique to grow a manganese-doped zinc-sulfide(ZnS：Mn) has been proposed using the repeated deposition of the Hot Wall method. The optical characteristics and crystallinity for the ZnS and ZnS：Mn thin films deposited on a quartz glass substrate by the method were investigated. Also, The ZnS：Mn thin film elcetroluminescent devices were fabricated by the method to study luminescence characteristics. All films showed (111)-oriented cubic structure. By the repeated deposition, the deposition rates were decreased, and the optical characteristics and crystalline properties were improved, which clarifies that the method is effective to deposit the thin films with good crystallinity Futhermore, the crystallinity was more improved by the doping of Mn. Only one peak emission at around 585nm originating from Mn luminescent center is observed In the photoluminescent and electroluminescent spectra of ZnS：Mn films and the luminance of the ZnS：Mn-based thin film electroluminescent devices was obtained below 60cd/$m^2$ . The optical and crystalline properties, luminescence characteristics are discussed in terms of the effects of the repeated deposition and Mn-doping.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.898-901
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• 2006

In this paper, effect of ceramic processing was investigated on the magnetic properties of low loss Mn-Zn ferrite. High frequency characteristics, high saturated magnetic flux density and high magnetic permeability and low magnetism loss are required for the development of Mn-Zn ferrite, which is parts in the communication. therefore, in order to improve Mn-Zn ferrite with a high frequency , it is important to have a minimal change of particles and to control the eddy current loss caused by high resistance of the stratum of particles and to reduce the hysteresis loss by uniform change of detailed structure. In this paper, we added $V_2O_5\;and\;CaCo_3$ to Mn-Zn Ferrite to achieve a high efficiency, low loss core material. The compositions are MnO : ZnO : $Fe_2O_3$ = 21 : 10 : 69 mol%. They were sintered at $1250^{\circ}C$ for Three hours. Initial permeability was measured at 0.1MHz. At 50mT, Power loss was measured by temperature changing at 100kHz.

• Journal of Environmental Health Sciences
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• v.13 no.1
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• pp.67-71
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• 1987

This study was intended to investigate the content of Cu, Mn, Zn in the dried milk powders except infant formula milkpowder from January to March, 1986. The content of the trace metals was determined by Atomic Absorption Spectrophotometry. The results were as follows: 1. Averages of Cu, Mn, Zn in the total samples were Cu, 0.3043 ppm Mn, 0.5101 ppm Zn, 26.006 ppm. 2. Averages and ranges of Cu, Mn, Zu in the whole milk powder were Cu, 0.2483, 0.216 - 0.48 Mn, 0.552 ppm, 0.336 - 0.732 ppm Zn, 28.961 ppm, 7.5 - 51.9 ppm. 3. Averages and ranges of Cu, Mn, Zn in the skim milk powder were Cu, 0.4095 ppm, 0.3 - 0.54 ppm Mn, 0.6907 ppm, 0.348 - 0.84 ppm Zn, 38.381 ppm, 30.6 - 55.2 ppm. 4. Averages and ranges of Cu, Mn, Zn in the modified milk powder were Cu, 0.3459 ppm, 0.12 0.948 ppm Mn, 0.2414 ppm, 0.096 - 0.348 ppm Zn, 7.752 ppm, 1.2 - 17.002 ppm. 5. It showed the highest amount of Cu, Mn, Zu in the skim milk powder group than in the other group and the lowest amount of Cu in the whole milk powder group and Mn, Zn in the modified milk group.

• Journal of the Korean Ceramic Society
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• v.30 no.1
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• pp.25-33
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• 1993

Formation reaction of Mn-Zn ferrite depending on various synthetic conditions of wet process was investigated using FeCl2.nH2O(n≒4), MnCl2.4H2O, ZnCl2 as starting materials. A stable intermediate precipitate was formed by the addition of H2O2. And the precipitate was hard to transform to spinel phase of Mn-Zn Fe2O4. Single phase of Mn-Zn Fe2O4 spinel was obtained above 8$0^{\circ}C$ reaction temperature. The powder had spherical particle shape and 0.02~0.05${\mu}{\textrm}{m}$ particle size. Fe(OH)2 solid solution, -FeO(OH) solid solution, -FeOOH, Mn-Zn Fe2O4 spinel were formed with air flow rate 180$\ell$/hr. However, single phase of Mn-Zn Fe2O4 spinel with cubic particle shape and 0.1~0.2${\mu}{\textrm}{m}$ particle size was formed with synthetic conditions of 8$0^{\circ}C$ and 90 munutes. The particle shape of the -FeOOH was needle-like.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.53-58
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• 2011

Cysteine and histidine-capped water-dispersible ZnS:Mn nanocrystals (ZnS:Mn-Cys and ZnS:Mn-His) were synthesized and their effects on E. coli and human cells were investigated. Particle sizes of these nanocrystals were found from HR-TEM images to be 3.5 nm and 4.0 nm, respectively. Their solution photoluminescence spectra showed identical broad emission peaks at 580 nm. ZnS:Mn-His significantly suppressed the growth of E. coli at $100{\mu}g/mL$ and 1 mg/mL concentrations, something not observed with ZnS:Mn-Cys. Consistent with this, greater inhibition of cell proliferation and viability were observed in HEK293 and IMR90 cells in ZnS:Mn-His at $100{\mu}g/mL$ and 1 mg/mL concentrations.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.162-167
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• 2023

Diverse structures of Mn oxides in natural and engineered systems occur from the transformation of δ-MnO₂, the most common crystalline phase of nucleated Mn oxides, to other structures via redox reactions, adsorption of metals, etc. Recently, together with emerging interests of Zn-based rechargeable battery systems, which use Mn oxides as a cathode, the transformation and recrystallization of Mn oxides have garnered interests. Here, using hydrothermal reaction of Zn-doped δ-MnO₂, the formation of todorokite and chalcophanite is observed. When the concentration of doped Zn increases, the formation of chalcophanite is dominant, but occurs slower than that of the lower concentration of doped Zn. This study will provide a new understanding of the effect of Zn on the recrystallization process of Mn oxides during redox cycles in energy storage systems and environmental systems.