• Title/Summary/Keyword: $SeO_3$

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Preparation and Photoluminescence Characteristics of Liquid Silicone Rubber Containing Cadmium Selenide Nanoparticles (Cadmium Selenide Nanoparticles을 함유하는 액상실리콘 고무의 제조와 형광특성)

  • Kang Doo-Whan;Lee Byoung-Chul;Kim Ji-Young
    • Polymer(Korea)
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    • v.30 no.3
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    • pp.266-270
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    • 2006
  • Poly [(dimethylmethylyinyl) siloxane] phosphineoxide (PMViSPO) was prepared by adding phosphorus oxychloride $(POCl_3)$ to poly (dimethylmethylyinyl) siloxane (PMViS) at $0^{\circ}C$ under nitrogen atmosphere. Cadmium selenide (CdSe) was prepared by reacting cadmium oxide (CdO), tetradecyl-phosphonic acid (TDPA), trioctylphosphine oxide (TOPO) at $300^{\circ}C$, and adding solution of dissolved Se to tributylphosphine (TBP) and trioctylphosphine (TOP) CdSe-poly [(dimethylmethylvinyl) siloxane] phosphine-oxide (CdSe-SPO) adduct was synthesised by adding PMViSPO to CdSe solution. Liquid silicone rubber composite (LSRC-1) was prepared by compounding $\alpha,\omega-vinyl$ poly (dimethylsiloxane) (VPMS), $\alpha,\omega-hydrogen$) poly(dimethylsiloxane) (HPMS), and CdSe under Pt catalyst, and also LSRC-2 was prepared from VPMS, HPMS, and CdSe-SPO using Pt catalyst. It was confirmed that CdSe nanoparticles with photoluminescence characteristics was dispersed uniformly in LSR matrix. The diameter of CdSe was $30\sim50nm$. By measuring the number of CdSe nanoparticles, 202 particles of CdSe in LSRC-2 and 165 particles of CdSe in LSRC-1 were dispersed in the same area of LSR matrix. Thermal stability for LSRC-2 compounded with CdSe-SPO was better than LSRC-1.

Fabrication of Mo Thin Film by Hydrogen Reduction of MoO3 Powder for Back Contact Electrode of CIGS (MoO3 분말의 수소환원을 통한 CIGS계 후면 전극용 Mo 박막제조)

  • Jo, Tae Sun;Kim, Se Hoon;Kim, Young Do
    • Korean Journal of Metals and Materials
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    • v.49 no.2
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    • pp.187-191
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    • 2011
  • In order to obtain a suitable back contacting electrode for $Cu(InGa)Se_2$-based photovoltaic devices, a molybdenum thin film was deposited using a chemical vapor transport (CVT) during the hydrogen reduction of $MoO_3$ powder. A $MoO_2$ thin film was successfully deposited on substrates by using the CVT of volatile $MoO_3(OH)_2$ at $550^{\circ}C$ for 60 min in a $H_2$ atmosphere. The Mo thin film was obtained by reduction of $MoO_2$ at $650^{\circ}C$ in a $H_2$ atmosphere. The Mo thin film on the substrate presented a low sheet resistance of approximately $1{\Omega}/sq$.

Effects or $H_2O$ Fraction or Dioscorea japonica Thunb with selenium on plasma Glucose and Lipid Metabolism in Streptozotocin Induced Diabetic Rats (당뇨 흰쥐에서의 참마 $H_2O$ 분획물과 Selenium 보충시 혈당 및 지질대사에 미치는 영향)

  • 김명화
    • Journal of Nutrition and Health
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    • v.31 no.9
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    • pp.1377-1384
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    • 1998
  • The purpose of this study was to investigate the effect of H$_2$O fraction of Dioscorea japonica Thunb(DJT) with selenium(Se) treatment on blood glucose and lipid metabolism in streptozotocin(STZ)-induced diabetic rats. Male Sprague-Dawley rats(180-220g) weighing were divided into five groups, that is one normal group and four diabetic experimental groups : the STZ-control group, the DJT group, the DJT-Se group and the Se group. Diabetes mellitus was induced in the male rats by injection of STZ into the tail vein at a dose of 45mg/kg B.W. The H,0 fraction of DJT(500mg/kg) given orally were administered for 14 days. The Se treated group were fed a AIN-76 recommendation diet mixed with Na$_2$SeO$_3$(2mg/kg diet), which was prepared fresh daily. The body weight and food intake was monitored daily and plasma levels of glucose, insulin, hematocrit and protein were determined. The plasma concentrations of cholesterol, HDL-cholesterol, triglyceride and fire fatty acid were measured. The activities of aminotrans ferase were analysed. The body weight gain was shown to be significantly higher in the normal group than all diabetic groups. The blood glucose levels of the DIT-Se group was significantly lower compared to those of the experimental groups. The administration of H$_2$O fraction of DJT and selenium showed an increase in plasma protein concentrations. The plasma cholesterol levels of all STZ-groups were not significantly different and HDL-cholesterol levels were increased in the diabetic experimental groups fed on H$_2$O fraction of DJT or Se supplementation. Plasma triglyceride levels were lower in the DJT-Se and Se group than in the STZ-control group. free fatty acid levels were not significantly differ among STZ-control groups. STZ treatment increased aminotransferase activity and that of DJT group was highest. In conclusion, the data from the present experiments indicate that the treatment of the H$_2$O fraction of DJT with selenium showed a synergistic effect and the two can have an influence on hyperg1ycemia and lipid metabolites when administered together. (Korean J Nutrition 31(9) : 1377-1384, 1998)

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Solution-Processed Anti Reflective Transparent Conducting Electrode for Cu(In,Ga)Se2 Thin Film Solar Cells (CIGS 박막태양전지를 위한 반사방지특성을 가진 용액공정 투명전극)

  • Park, Sewoong;Park, Taejun;Lee, Sangyeob;Chung, Choong-Heui
    • Korean Journal of Materials Research
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    • v.30 no.3
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    • pp.131-135
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    • 2020
  • Silver nanowire (AgNW) networks have been adopted as a front electrode in Cu(In,Ga)Se2 (CIGS) thin film solar cells due to their low cost and compatibility with the solution process. When an AgNW network is applied to a CIGS thin film solar cell, reflection loss can increase because the CdS layer, with a relatively high refractive index (n ~ 2.5 at 550 nm), is exposed to air. To resolve the issue, we apply solution-processed ZnO nanorods to the AgNW network as an anti-reflective coating. To obtain high performance of the optical and electrical properties of the ZnO nanorod and AgNW network composite, we optimize the process parameters - the spin coating of AgNWs and the concentration of zinc nitrate and hexamethylene tetramine (HMT - to fabricate ZnO nanorods. We verify that 10 mM of zinc nitrate and HMT show the lowest reflectance and 10% cell efficiency increase when applied to CIGS thin film solar cells.

The CO sensing properties of thick film gas sensor using Co3O4 powders prepared by hydrothermal reaction method (수열합성법으로 제조된 Co3O4 분말을 사용한후막 가스센서의 CO 감지 특성)

  • Kim, Kwang-Hee;Kim, Jeong-Gyoo;Park, Ki-Cheol
    • Journal of Sensor Science and Technology
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    • v.19 no.5
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    • pp.385-390
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    • 2010
  • CO sensing thick film gas sensors using $Co_3O_4$ powders prepared by hydrothermal reaction method, were fabricated, and their structural, electrical and CO gas sensing properties were investigated. The specific surface area of the $Co_3O_4$ powders obtained from BET analysis was about 79.0 $m^2/g$. XRD and SEM results show that the thick films heat-treated at $500^{\circ}C$ for 30 min after screen printing had the preferred orientation of (311) direction and the crystalline size was calculated to 221 $\AA$. The maximum activation energy obtained from the temperature-resistance characteristics was 3.11 eV in the temperature range of $290^{\circ}C$ to $310^{\circ}C$. The sensitivity to 1,000 ppm CO was about 150 %. The specific surface area, crystalline size, and maximum activation energy were increased significantly and the sensitivity for CO gas was improved largely.

The Effect of Additives on Twining in ZnO Varistors

  • Han, Se-Won;Kang, Hyung-Boo
    • The Korean Journal of Ceramics
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    • v.4 no.3
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    • pp.207-212
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    • 1998
  • By comparison of the experimental results in two systems of ZnO varistors, it's appear that Sb2O3 is the indispensable element for twining in ZnO varistors and the Zn7Sb2O12 spinel acts as the nucleus to form twins. Al2O3 is not the origin of twining in ZnO varistor, but it was found that Al2O3 could strengthen the twining and form a deformation twining by ZnAl2O4 dragging and pinning effect. The inhibition ratios of grain and nonuniformity of two systems ZnO varistors increase with the increase of Al2O3 content. The twins affect the inhibition of grain growth, the mechanism could be explained follow as: twins increase the mobility viscosity of ZrO grain and grain boundary, and drag ZrO grain and liquid grain boundary during the sintering, then the grain growth is inhibited and the microstructure becomes more uniform.

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