• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.759-761
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• 2002

A new method for the preparation of copper activated zinc sulfide phosphors by combustion method has been proposed. Copper nitrate was decomposed with an organic fuel to give fine sized particles in presence of alkali metal halides at low temperature than the conventional synthesis. Organic compound also acted as fuel at 500 $^{\circ}C$ with rapid heating. The phosphors thus obtained were then heated at 900 $^{\circ}C$ in an inert atmosphere for 2-5 hrs to get better luminescent properties.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.281-296
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• 2010

방그라데시 북부에 위치한 풀바리 우파질라 지역의 지하수에서 pH, EC, 주요 양이온 ($Ca^{2+}$, $Mg^{2+}$, $Na^+$, $K^+$, $Zn^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Fe^{3+}$, and $As^{3+}$), 주요 음이온 (${CO_3}^{2-}$, $HCO_3{^-}$, $NO_3{^-}$, ${SO_4}^{2-}$ and $Cl^-$) 그리고 total dissolved solids (TDS) 등의 용존물질 함량을 측정하였다. 또한 sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), 경도 등의 지표도 계산하였다. 전체적으로 지하수의 pH는 약알칼리성 (6.24 - 8.10)을 띄었으며, 주요 양이온은 $Ca^{2+}$, $Mg^{2+}$ and $Na^+$ 이었고, 주요 음이온은 $HCO_3{^-}$ and $Cl^-$ 으로서 전형적인 담수의 이온조성을 보였다. $Cu^{2+}$, $Mn^{2+}$ and $Fe^{3+}$ 의 최대 농도는 각각 1.71, 0.606, 0.125 mg/L 이었다. 방글라데시의 여러 지역에서는 비소에 의한 지하수의 오염이 흔히 나 타나고 있으나 이지역에서 비소의 최대농도가 0.41 mg/L로서 기준치인 0.05 mg/L 보다 낮은 오 염도를 보였다. TDS와 SAR, SSP 등으로 볼 때 이 지역의 지하수는 대부분 양호한 수질을 가지는 담수인 것으로 평가된다. $As^{3+}$, $Zn^{2+}$, $Mn^{2+}$, $Fe^{3+}$, ${SO_4}^{2-}$, $NO_3{^-}$ and $Cl^-$ 등의 농도는 음용수로 적합한 수준이었으나 일부 항목은 특정 산업용도로는 부적합한 농도를 보였다. 현재로서는 이지역 의 지하수는 대부분 음용이 가능하고 일부 산업용에 대해서만 부적합성을 보였다. 그러나 앞으로 지 하수의 이용과 산업활동이 증가하면 방글라데시의 많은 다른 지역의 지하수에서 발생한 사례와 같 이 용존물질의 농도가 증가하여 물의 용도에 제한을 받게 될 우려가 있다.

• Asian Journal of Atmospheric Environment
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• v.11 no.2
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• pp.122-130
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• 2017

The main purpose of the study was to clarify the properties of individual particles collected at each behavior space of a factory worker. The samplings of size-segregated ($PM_{2.1-1.1}$ and $PM_{4.7-3.3}$) indoor particles were conducted at three different behavior spaces of a factory worker who is engaged in an auto parts manufacturing plant (i.e., his home, his work place in factory, and his favorite restaurant). Elemental specification (i.e., relative elemental content and distribution in and/or on individual particles) was performed by a micro-PIXE system. Every element detected from the coarse particulate matters of home was classified into three groups, i.e., a group of high net-counts (Na, Al, and Si), a group of intermediate net-counts (Mg, S, Cl, K, and Ca), and a group of minor trace elements (P, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb). The results of EF for $PM_{4.7-3.3}$ in home indicated that several heavy metals were generated from the sources within the house itself. An exceptional feature shown in the individual particles in workplace is that Cr, Mn, and Co were clearly detected in both fine and coarse particles. Cluster analysis suggested that the individual coarse particles ($PM_{4.7-3.3}$) collected at the indoor of factory were chemically heterogeneous and they modified with sea-salt, mineral, and artificially derived elements. The principal components in individual coarse particles collected at restaurant were sea-salt and mineral without mixing with harmful trace elements like chromium and manganese. Compared to the indoor fine particles of home and restaurant, many elements, especially, Cl, Na, Cr, Mn, Pb, and Zn showed overwhelmingly high net-counts in those of factory.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.1-6
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• 2000

In this paper, organic dispersion type back light EL(Electroluminescent) devices were manufactured using Ethyl hydroxy ethyl cellulose as organic binder, ZnS:Cu as phosphor powder and $BaTiO_3$ as dielectrics by screen printing method, which are focused on as a new light source. The properties of the fabricated organic dispersion type back light EL devices were showed $1.98[mA/\m^2]$ of current density, 0.075[W] of power consumption, 7.1[nF] of capacitance at $25[^{\circ}C]$, 100[V], 400[Hz], respectively. Also brightness of the fabricated device was revealed $20~110[cd/\m^2]$ at 50~150[V] and the change of color was shoed bluish green of x=0.1711, y=0.3676 which are color coordinate by CIE.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.407-407
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• 2008

무기EL 디스플레이는 고체재료에 전계를 가했을 때 발광하는 현상을 이용한소자로서, 급속도로 발전을 거듭하고 있으나, 유전체층에 강한전계를 가하여 발광하여야 하므로 낮은 Breakdown voltage와 효율의 한계로 인하여 휘도가 낮고 풀 컬러화 디스플레이 등 의 응용에는 적용되고 있지 못하는 실정이다. 본 연구에서는 강유전체 Perovskite 구조를 가지는 ABO3 물질 중 PMN(Lead Magnesium niobate) 과 PZT (Lead Zirconate titanate) 후막을 제조하여 Inorganic EL(Electro Luminance)에 적용하고 소자의 광전특성을 평가하였다. 소자에 사용된 기판은 고온소성에 알맞은 알루미나(Al2O3)기판을 채택 하였으며, 그 위 하부전극으로는 고온소성에 따른 화학적 안정성이 우수한 Au전극을 Screen Printing 하였다. 제조 되어진 PMN후막 페이스트는 PMN(Pb(Mg1/2 Nb2/3)O3) + Glass Frit(Pb-Zn-B) + BaTiO3(99.99%) 로 합성되었으며 하부전극위에 인쇄하였다. 그 다음 PZT sol-gel을 Spin coating으로 도포 하였다. 형광체로 ZnS:Cu.Cl 을 Screen Printing을로 형성하였으며, 평탄화를 위하여 유기물 충을 Screen Printing 공정으로 성막 하였다. 상부전극으로는 DC sputter로 ITO를 증착하여 EL소자 완성 후 Spectro - Chroma meter로 소자특성을 측정하였다. 평탄화를 통한 유기물층에 변화되는 Capacitance를 Oscilloscope로 전압 전류 pulse의 변화에 따른 opto-electronic 특성을 평가하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.490-495
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• 1994

Acid phosphatase (EC3.1.3.2) from carrots was partially purified by ammonium sulfate fractionation (30%-80%), Sephacryl S-200 gel filtration, cm-Sepharose CL-6B and DEAE -Sephacel ion exchange chromatography. The optimum ph and temperature of acid phosphatase from carrots were pH 5.5 and 55$^{\circ}C$, respectively. The enzyme was most stable at ph 6.0 and relatively unstable below pH 4.0 . The activation energy of the enayme was determined to be 10.6kcal/mole. The enzyme utilized p-nitrophenyl phosphate as a substrate among tested possible substrates, whereas it hydrolyzed 5' -IMP and 5'-GMP poorly. The Michaelis -Menten constant(Km) of the enzyme with p-nitrophenyl phosphate as a substrate was identified as 0.55mM. Amongtested metal ions and inhibitors, Al+++ Zn++, Cu++ , fluoride, metavanadate and molybdate ions inhibited the enzyme activity drastically.

• Journal of Environmental Health Sciences
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• v.16 no.2
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• pp.41-45
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• 1990

This study was performed to analyze for the mineral water (Saeng Su) from 12 pure beverage Co. products, which was obtained during March to May in 1988. The results were as follows: 1. The analytical results of contaminant materials in all the samples were suitable for drinking water standard. The mean value of NH$_{3}$-N, NO$_{3}$-N, Cl-and KMnO$_{4}$ consumption were ND, 49mg/l, 1.08mg/l and 8.14mg/l, respectively. 2. Total bacterial counts were 3/cc in average and Coliforms was negative in all samples. 3. The analytical results of Heavy metals were not detected or detected in a small amount, and the contents were different from each company. The CN, Hg, P were not detected in all the samples and the mean value of Cu, Fe, Mn were 0.0087mg/l, 0.0303mg/l, 0.018mg/l, respectively and it's contents were low. 4. The mean value of Pb, Zn, Cr$^{+6}$, As and Cd were 0.016mg/l, 0.015mg/l, 0.0025mg/l. 0.0059mg/l and 0.0011mg/l respectively.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.926-931
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• 2011

A series of complexes of the type [$ML_2Cl_2$], where L=2-(o-anisylidene-2'-imino) amino benzimidazole (AIAB) and 2-(furfurylidene imino) amino benzimidazole (FIAB), M=Cu(II), Co(II), Ni(II) and Zn(II), have been synthesized and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR spectral studies. The results are in consistent with bidentate chelation of ligand with azomethine nitrogen and ring nitrogen donors. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis, Bacillus stearothermophilus, Escherichia coli and Salmonella typhi) and antifungal activities (Aspergillus niger and Aspergillus flavus).

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.572-577
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• 1989

Using the low valent titanium induced carbonyl-carbonyl coupling reaction, it was attempted to synthesize sterically hindered 17-membered cyclic chiral host 2. The semifinal dialdehyde 12 was obtained through 11 step reactions beginning from p-tert-butylphenol and dibenzofuran. When dialdehyde 12 was treated with $TiCl_3-Zn/Cu,$ only intermolecularly coupled dimer 14 was obtained instead of intramolecularly coupled cyclic alkene 2. The mechanistic consideration leading to 14 was discussed and the cation binding properties of dimer 14 and dicarboxylic intermediate 13 was reported, which implies the significance of the principle of preorganization of host's binding sites prior to complexation.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.191-198
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• 2018

Improper management and unsanitary approaches are implemented in disposal of leachate, which has resulted in groundwater pollution at village Uruli Devachi, Pune, India. Various physico-chemical treatment methods are commercially available for leachate treatment. However, the application of biological methods viz. phytoremediation to the municipal solid waste landfill leachate has been limited. We report the remediation ability of Typha aungstifolia and Acrorus calamus that is capable of reducing hazardous constituents from the landfill leachate. After 96 h of hydraulic retention time (HRT), it was observed that T. aungstifolia-treated sample showed high reduction potential in reducing biochemical oxygen demand, chemical oxygen demand, hardness, total dissolved solids, Na, Mg, Ca and Ni whereas A. calamus showed greater reduction capacity for alkalinity, Cl, Cu, Zn and Cr. Furthermore, it was also observed that T. aungstifolia withstood longer HRT than A. calamus. In situ application of T. aungstifolia and A. calamus for remediation of landfill leachate carries a tremendous potential that needs to be further explored.