수용액에서 연료용 수소를 얻기 위한 MgFe_2O_4 광반도성 전극의 제조와 특성에 대하여

김일광,이홍,최창진,김윤근,천현자 圓光大學校 基礎自然科學硏究所 1987 基礎科學硏究誌 Vol.6 No.2

In the light of the rarity of p-type semiconducting oxides and the unusual properties of the magnesium-iron-oxygen system, it is worthwhile to examine the solied state and photoelectrochemical properties of these materials more closely. This work presented an investigation of the preparation and characterization of magnesium-substituted ironoxid ceramics. Sintered discs of magnesium substituted ironoxides were prepared by conventional powder state mixing techniques. X-ray diffraction and scanning electron microscopy experiments showed that these materials are multiphase, containing both MgFe_2O_4 corundum phase and a spinel phase. More important, photoelectrochemical experiments using the ceramic discs as photoelectrodes showed both cathodic photocurrents and anodic photocurrents under illumination. Photochemical and electrochemcal techniques have been used to show that the inhomogeneities of these materials in the near surface region may be related to the photoelectrochemical properties of the magnesium substituted ironoxide bi-type photoelectrodes.

Micelle 용액에서 Co(II)-tetraphenylporphyrin의 전기 화학적 환원에 관한 연구

金日光,金潤根 圓光大學校 基礎自然科學硏究所 1985 基礎科學硏究誌 Vol.4 No.1

The electrochemical reduction of Co(Ⅱ)-tetraphenylporphyrin at a static mercury drop electrode in micelle nonaqueous solution has been examined DC polarography, DP and cyclic voltammetry. The polarographic data shown to be three-electron transfer in three reduction steps. But, the cyclovoltammetric results shown to be four reduction steps in electrode reaction. The reduction waves shown to be three reversible electron transfer and one irreversible electron transfer reduction. The hight of reduction waves were eliminated in the cationic surfactant CTABr and nonionic surfactant triton x-100 solution. In anionic surfactant NaLS solution, the half-wave potential was shifted to the high negative potential and the height is increased.

Acetonitrile 용액중에서 살충제 O,O-Dimethyl-O-(3-methyl-4-nitrophenyl)-phosphorothioate(Fenitrothion)의 전기화학적 환원에 대한 연구

金日光,金潤根,千賢子,朴勝熙 圓光大學校 基礎自然科學硏究所 1986 基礎科學硏究誌 Vol.5 No.2

The electrochemical reduction of o,o-dimethyl-o-(3-methyl-4-nitrophenyl)-phosphorothioate(fenitrothion)has been studied in acetonitrile solution containing surfactant micelle by direct current(DC)-differential pulse(DP) polarography, cyclic voltammetry(CV) and controlled potential coulometry(CPC). The totally quasiirreversible electron transfer-chemical reaction (EC, EC mechanism) of fenitrothion reduction proceeded by four electron transfer to form o,o-dimethyl-o-(3-methyl-4-hydroxyaminophenyl)-phosphorothiate which undergoes single bond of the phosphorus atom and phenoxy group cleaves to give p-hydorxyamino-m-cresol and dime-thyl thiophosphonate as major product by two electron transfer-protonation. The polarograpic reduction waves shown to be reversible adsorption current (-0.9 volts vs.Ag-AgCl) in sodium lauryl sulfate micelle solution and split up on selectivity of anionic micelle effect in two step at the first reduction peak.

3-Phenyl-4-nitrosydnone의 전기화학적 연구

金日光,金潤根 圓光大學校 基礎自然科學硏究所 1986 基礎科學硏究誌 Vol.5 No.2

An electrochemical reduction on the 3-phenyl-4-nitrosydnone in acetonitrile solution has been studied by direct current differential pulse polarography, cyclic voltammetry and controlled potential coulometry. Before the cleavage of phengl-N single bond a reversible electron transferchemical reaction (EC) mechanism of nitro functional group proceeded to form amino (orhydroxylamino) group by multielectron transfer which is followed to give phenyl glycine (or phenyl hydrazine) by single electron transfer-chemical reaction at the 2nd and 3rd irreversible reduction wave of high negative potential region. The cathodic half-wave potentials shown to be negative shift due to inhibition effect of cetyl-trimethyl ammonium bromide micelle while the sodium lauryl sulfate micelle showed reversible anodic peaks on the 2nd, 3rd reduction waves at high negative potential region.

e-CRM을 위한 웹사이트 방문자 성향분석 시스템의 설계 및 구현

김창근,김흥준,정연홍 진주산업대학교 산업과학기술연구소 2005 산업과학기술연구소보 Vol.- No.12

If web users visit highly attractive pages during the navigation pattern, they spend more time over viewing and visiting the pages. This can be important information for electric commerce as well as for website owners to analyze what web sufferer’s tastes are. This paper is designated to find out sufferer’s precise taste by estimating how much time sufferers’ spent in certain sites that they have visited.

비수용액에서 Co(II)-tetraphenylporphyrin의 전기 화학적 연구

金日光,金潤根 圓光大學校 基礎自然科學硏究所 1985 基礎科學硏究誌 Vol.4 No.1

The electrochemical behavior of Co(Ⅱ)-tetraphenylporphyrin at a static mercury drop electrode in a nonaqueous solution has been examined by DC polarography, DP polarography, cyclic voltammetry and controlled potential coulometry. The polarographic data showed well diffusion controlled reduction process of three-electron transfer in three reduction steps. But, the cyclovoltammetric results showed four reduction steps in electrode reaction. The reduction waves shown to be three reversible electron transfer and one irreversible electron transfer reduction. The possible mechanism on the electrochemical reduction of Co(Ⅱ)-tetraphenylporphyrin was suggested.

물과 Micelle 용액에서 Benzaldehyde의 전기화학적 환원에 대한 연구

金日光,金潤根,金峯元,印權植 圓光大學校 基礎自然科學硏究所 1988 基礎科學硏究誌 Vol.7 No.3

The electrochemical reduction of benzaldehyde in 10% ethanol-water solution contained surfactants has been studied by direct current (DC) differential pulse (DP) polarography, cyclic voltammetry (CV) and controlled potential coulometry (CPC). A totally irreversible electrode reaction processes of benzaldehyde reduction proceeded by one electron transfer to form anion radical which undergoes both protonation and a second one electron reduction to give benzyl alcohol as a major product. The cathodic reduction wave was seperated by inhibition of sodium lauryl sulfate due to selectivity and effect of anionic charged micelle. The possible reduction mechanism with controlled pH range was suggested.

Acetonitrile 용액중에서 살충제 O, O-Dimethyl-O-(3-Methyl-4-Nitrophenyl)-Phosphorothioate (Fenitrothion)의 전기화학적 환원

金日光,金潤根,千賢子 圓光大學校 基礎自然科學硏究所 1989 基礎科學硏究誌 Vol.8 No.3

계민활성 micelle을 형성하는 acetonitrile 용액에서 O,O-dimethyl-O-(3-methyl-4-nitrophenyl)-phosphorothioat(Fenitrothion)의 전기화학적 환원을 direct current 및 differential pulasepolarography, cyclic voltammetry 그리고 controlled potential coulometry 방법으로 연구하였다. Fenitrothion의 환원 과정은 1단계로 4 전자 이동에 의한 부분 가역적 전자이동 화학반응 (EC, EC)기구로 O,O-dimethyl-O-(3-metbyl-4-hydroxyaminophenyl)-Phosphorothioate를 형성하고, 더 높은 음전위에서 2 전자 이동에 따른 양성자 반응으로 phosphorus 원자와 phenoxy group의 단일 결합이끊어지면서 주생성물인 P-amino-m-cresol과 dimethyl thiophosphinic acid를 생성하였다. Sodiumlauryl sulfate micelle 용액에서 polarography 환원파는 전체적으로 억제 되었으며 특히 1차 환원파는 음이온 micelle의 선택적 작용으로 2단계로 분리되었다. The electrochemical reduction of O,O-dimethyl-O-(3-methyl-4-nitropheny1)-phos-phorothioate(Fenitrothion) has been studied in acetonitrile solution containing surfactant micelleby direct current (DC)-differential pulse (DP) polarography, cyclic voltammetry (CV) and controlled potential coulometry (CPC). The partially reversible clectron transfer-chemical reaction(EC,EC mechanism) of fenitrothion reduction proceeded by four electron transfer to form O.0-dimethyl-O-(3-methyl-4-hydroxyaminophenyl)-phosphorothioate which undergoes sing1e bond of the phosphorus atom and phenoxy group cleaves to give p-amino-m-cresol and dimethyl thiophosphinic acid as major product by two electron transfer-protonation at higher negative potential. The polarograpic reduction waves shown to suppressed due to inhibitory effect of sodium lauryl sulfate micelle solution and split up on selectivity of anionic micelle effect in two step at the first reduction peak.

Chromium(Ⅲ)의 전기화학적 환원에 관한 연구

김일광,김윤근,김세봉 圓光大學校 基礎自然科學硏究所 1987 基礎科學硏究誌 Vol.6 No.1

The electrochemical reduction of chromium(Ⅲ)in 1×10exp(-1)M sodium perchlorate and 1×10exp(-2)M sulfuric acid aqueous solution has been examined by polarography and cyclic voltammetry. The cyclovoltammetric results showed quasirreversible electrode processes that reduction of chromium(Ⅲ) proceeds by two electron transfer at first reduction step and second reduction step of one electron transfer followed to form chromium metallic state although the direct current polarogram shown to be a three electron transfer process in one reduction step. The height of reduction wave was suppresed and strongly shifted to the more negative potential in cationic surfactant(CTABr), nonionic surfactant triton x-100 and EDTA effects. In anionic surfactant NaLS solution, the height was increased while the half-wave potential shifted to the height negative potential.

3-Phenyl-4-Nitrosydone의 전기화학적 연구

金日光,金潤根,韓順鍾 圓光大學校 基礎自然科學硏究所 1989 基礎科學硏究誌 Vol.8 No.3

Aretonitrile 용액중에서 3-phenyl-4-nitrosydnone의 전기화학적 환원을 direct current,differential Pulse polarography, cyclic voltammetry 그리고 controlled potential coulometry 방법으로연구하였다. Phenyl-N 단일 결합의 분리 이전에 nitro 기능기의 비가역적 전자전달-화학반응(EC)기구의 진행으로 다전자 이동에 의한 amino(또는 hydroxylamino)기를 형성하고, 높은 음전위 영역에서 제 2,3 비가역성 환원파의 일전자전달-화학반응에 의한 phenyl hydrazine을 생성하였다. 음극 반파 전위들은 cetyltrimethyl ammonium bromide의 억제효과에 의해 음의 값으로 이동하였고한편, sodium lauryl sulfate micelle은 높은 음전위 영역에서 제 2,3 환원파의 가역성산화 peaks를보였다. An electrochemical reduction on the 3-phenyl-4-nitrosydnone in acetonitrile solu-tion has been studied by direct current, differential pulse polarography, cyclic voltammetry andcontrolled potential coulometry. Before the cleavage of phenyl-N single bond a irreversible elect-ron transfer-chemical reaction(EC) mechanism of nitro fuctional group proceeded to form amino(or-hydroxylamino) group by multielectron transfer whick is followed to give phenyl hydrazineby single electron transfer-chemica1 reaction at the 2nd and 3rd irreversible reduction wave of highnegative potential region. The cathodic half-wave potentials shown to be shift negative due toinhibitory effect of cetyl-trimethyl ammonium bromide micelle whi1e reversible anodic peaks onthe 2nd and 3rd reduction waves in the presence of NaLS at high negative potential region.