• Title/Summary/Keyword: KBr

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Uv/ZnO에 의한 타르색소의 분해에 관한 연구

  • 정갑섭;나석은;최수일
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11b
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    • pp.305-307
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    • 2003
  • Uv/ZnO를 이용한 타르색소의 광촉매 분해에 대한 실험적 검토로부터 전 실험범위에서 tartrazine의 분해효과가 brilliant blue FCF보다 높았고. 두 색소 모두 ZnO의 투입량이 증가할수록 분해도가 증가하였으며, $KBrO_3$보다 (${(NH_4)}_2S_2O_{8}$의 분해촉진 효과가 더 컸으나 pH의 영향은 그다지 크지 않은 것으로 나타났다.

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Purification and Characterization of Apolipophorin-III from Haemolvmph of Fall Webworm Hvphantria cunea Drury (미국흰불나방(Hyphantria cunea Drury) 혈림프부터 apolipophorin-III의 순수정제 및 특성)

  • 윤화경;서신자김학열
    • The Korean Journal of Zoology
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    • v.37 no.4
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    • pp.488-494
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    • 1994
  • Apolipophorin-III (ApoLp-III) was purified from adult haemolynph of Hyphantriu cuneo and their molecular weight and synthetic place were investigated. ApoLp-III purification was performed by KBr-density gradient ultracentrifugation followed by gel permeation chromatographv (Sephadex G-1001 and ion-exchange chromatography (CM-52) and their purity was confirmed on 10% SDS-PAGE. ApoLp-III has the molecular weight of 18 ItDa and is synthesized by fat body.

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Thin film growth by charged clusters

  • Hwang, N.M.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1998.09a
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    • pp.33-33
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    • 1998
  • Invisible charged clusters are suggested to form in the gas phase and to become the growth unit in the thin film process. Similar suggestion had been made by Glasner el al. in the crystal growth of KBr and KCL in the solution where the lead ions were added. The charged cluster model, which was suggested in the diamond CVD process by our group, will be extended to the other thin film processes. It will be shown based on both the theoretical analysis and the experimental evidences that the charged clusters are formed in the gas phase and become the growth unit of the crystal in the thin film process.

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Synthesis of $Cp^*Ru(CO)Cl_2(Cp^*={\eta}^5-C_5Me_5)$ Complex and Reaction with Phosphines ($Cp^*Ru(CO)Cl_2(Cp^*={\eta}^5-C_5Me_5)$착물의 합성과 포스핀과의 반응)

  • Lee, Dong Hwan;Kim, Sng Il;Jun, Jin Hee;Oh, Yung Hee;Kam, Sang Kyu
    • Journal of the Korean Chemical Society
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    • v.41 no.12
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    • pp.639-644
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    • 1997
  • Novel carbonylruthenium (Ⅲ) complex Cp*Ru(CO)Cl2(2, Cp*=η5-C5Me5) was synthesized by the reaction of [Cp*RuCl2]2(1) with CO in toluene. The effective magnetic moment (Veff=1.81 B.M.) derived from the magnetic susceptibility measurement of the complex (2) was consistent with the presence of one "single" unpaired electron. Dibromocarbonylruthenium (Ⅲ) complex Cp*Ru(CO)Br2(3) was obtained by the reaction of complex (2) with KBr in toluene. Complex (2) was easily reduced by the reaction with phosphine in toluene to give the corresponding Ru (Ⅱ) complex Cp*Ru(CO)(PR3)Cl (4a∼4e, PR3=PMe3, PEt3, PMePh2, PPh3, PCy3).

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Oxidation of Benzyl Ethers in Sodium Hypochlorite Mediated Piperidine-1-oxyl System (촉매량의 Piperidine-1-oxyl과 NaOCl계에서 벤질 에테르 유도체들의 산화 반응)

  • Cho, Nam Sook;Park, Chan Heun
    • Journal of the Korean Chemical Society
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    • v.39 no.8
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    • pp.657-665
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    • 1995
  • The oxidation of various benzyl ethers and benzyl alkyl ethers to benzoates has been studied in two-phase system of $CH_3CO_2Et$ and aqueous NaOCl (6.6 mol eq.). The oxidant N-oxo-4-methoxy-2,2,6,6-tetramethylpiperidium bromide (N-oxoammonium salt) was prepared in situ and recycled by addition of 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl (0.03 mol eq., 4-methoxy-TEMPO), co-catalyst KBr (0.03mol eq.) and second oxidant NaOCl. Thus the catalytic amount of 4-methoxy-TEMPO was used. An adjustment of the pH value of below 8.0 was also required for this reaction with 2.5 hr of reaction time at 0∼5$^{\circ}C$. Under these conditions benzyl ethers were oxidized to benzoates. The selectivity of oxidation of benzyl alkyl ethers is dependent on the acidity of hydrogen and steric effect of alkyl group.

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Characterization and Distribution of Transferrin from the Last Larval Haemolymph of Papilio xuthus (호랑나비 유충 혈림프 Transferrin의 특성과 분포)

  • Shin, Myung-Ja;Kim, Kyoung-Keun;Kim, Jeong-Sook;Lim, Jae-Hwan;Seo, Eul-Won
    • Journal of Life Science
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    • v.17 no.8 s.88
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    • pp.1046-1052
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    • 2007
  • Transferrin is a molecule carrying iron to store and maintain for iron homeostasis of living organisms. In this study, we have purified transferrin, as an iron-binding protein, from the last larval haemolymph of Papilio xuthus by KBr density gradient ultracentrifugation and gel filtration (superose 6 HR) using fast protein liquid chromatography (FPLC) and transferrin containing iron was identified by Ferene S staining. The purified haemolymph transferrin was shown to have molecular mass of 78 and 80 kDa and amino acid composition of transferrin was rich in aspartic acid, valine, leucine and glutamic acid. With immuno-diffusion assay, we confirmed the existence of the transferrin in the haemo-lymph and fat body by detection of visible and clear positive reaction. From the quantitative comparison by rocket immuno-electrophoresis process, the amount of transferrin were increased in the haemolymph of 3 days after pupation and the whole 5 days after pupation. Here, with biochemical and immunohistochemical analysis, we speculate the relationship of transferrin between the physical characteristics and distribution during metamorphosis of P. xuthus.

Kinetics Study of the Reaction of Bromine with Phenylhydrazine in Sulfuric Acid Media (페닐히드라진과 브롬의 반응메카니즘에 관한 연구)

  • Park Byoung Bin;Park Il H.;Kong Young Kun;Choi Q. Won
    • Journal of the Korean Chemical Society
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    • v.21 no.4
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    • pp.227-234
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    • 1977
  • The reaction of phenylhydrazine with bromine in sulfuric acid solution has been studied kinetically. The pseudo-second-order rate constant is approximately inversely proportional to hydrogen-ion concentration when the concentration of sulfuric acid is lower than 1M. arom the study of the effect of potassium bromide concentration on the rate constant, it is concluded that both neutral bromine and tribromide ion participate in the reaction, the rate constants in 0.01M $H_2SO_4$ being $5{\times}10^5M^{-1},sec^{-1}\;and\;0. 7{\times}10^5M^{-1},sec^{-1}$, respectively at $20^{\circ}C$. The pseudo-second-order rate constant of 2.4-dinitrophenylhydrazine-bromine reaction is independent of hydrogen ion concentration. From the KBr addition experiment, the rate constants for $Br_2\;and\;Br_3^-$ were obtained as $1.2{\times}10^5M^{-1},sec^{-1}\;and\;2.0{\times}10^4M^{-1},sec^{-1}$, respectively.

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Application of Infrared Spectroscopical Techniques for Investigation of Archaeological Woods (적외선(赤外線)(IR) 분광법(分光法)에 의한 고목재(古木材) 성상(性狀)의 심지(深知))

  • Kim, Yoon-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.16 no.4
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    • pp.3-9
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    • 1988
  • Infrared (IR) spectroscopic techniques for the analysis of wood samples and the absorbance spectra of solid woods were presented. KBr pellets were prepared by throughly mixing approximately 300 mg of dried KBr and 1 mg of finely milled wood powder extracted with ethanol-cyclohexane previously. This mixture was made into a transparent disc by means of a pellet-making die (10 ton/$cm^2$ for 10 min). This IR techniques were applied for the analysis of archaeological wood samples. The most notable difference in the IR spectra between the recent and the archaeological waterlogged woods is that the absorption band centered at $1,730cm^{-1}$ was significantly diminished in the waterlogged ones. Total loss of absorption in $1,730cm^{-1}$ might be mainly due to the result of hemicellulose degradation. Another feature indicated by IR spectral comparision are that the degraded waterlogged wood samples showed 1) the increased intensity of the 1,600, 1,500 and $1,270cm^{-1}$ due to the residual lignin and the increased intensity at 1,470 and $1,425cm^{-1}$ due to the degradation of hemicellulose and 2) to the emergence of single band around $1,050cm^{-1}$ instead of three bands at 1,110, 1,060 and $1,040cm^{-1}$ in recent wood due to the degradation of cellulose crystalline. It was revealed from the IR examinations that the first change of wood in the waterlogged situation was the lysis of hemicellulose and the second the lysis of cellulose. It was also suggested that IR spectroscopy could serve a fast method for the investigation on the chemical characteristics of archaeological wood samples.

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Kinetics of Ethyl Phenylcarbamate Synthesis by the Oxidative Carbonylation of Aniline (아닐린의 산화적 카르보닐화에 의한 에틸페닐카바메이트의 합성의 속도론적 고찰)

  • Park, Nae-Joung;Park, Jae-Keun
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.710-716
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    • 1992
  • Ethylphenyl carbarmate(EPC) was synthesized by oxidative CO carbonylation of aniline in the presence of transition metal catalysts and alkali metal halide cocatalysts at $120^{\circ}C$ under the pressure of 79atm. Oxygen gas was used for oxidizing agent. Kinetics of the reaction was studied and activation energies with different catalysts were estimated. About 100% conversion to EPC and 95% selectivity was obtained in 5 hour reaction. 5% Pd/C was more effective than 5% Rh/C. Effectiveness of cocatalysts was in the order of KI>KBr>KCl. As the temperature increased from $75^{\circ}C$ to $120^{\circ}C$, the conversion rate increased. The reaction was apparent first order and the activation energies with 5% Pd/C and 5% Rh/C were 5.647 and 5.780 kcal/mol, respectively.

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XPS Analysis of Acrylic Acid Films Polymerized by Remote Plasma-Enhanced Chemical Vapor Deposition (원격 플라즈마 화학기상증착법에 의해 중합된 아크릴산 필름의 XPS 분석)

  • Kim, Seonghoon;Seomoon, Kyu
    • Applied Chemistry for Engineering
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    • v.20 no.5
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    • pp.536-541
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    • 2009
  • Plasma-polymerized acrylic acid films were deposited on Si wafer and KBr pellet by remote plasma-enhanced chemical vapor deposition (PECVD). Effects of plasma power, reaction pressure, indirect plasma method on the growth rate, chemical structure, and chemical bonding state of the films were investigated. Chemical structure and chemical state of the films were characterized by Fourier transformed infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis and curve fitting technique. Growth rate of the film increased to a saturation value with plasma power of 100 W, but showed the maximum with reaction pressure at 300 mtorr. Whenever W/FM factor (applied energy per gas molecule) increased by increasing plasma power or lowering pressure, the fragmentation of acrylic acid molecules was promoted. From the XPS curve fitting analyses, we found that the intensity of carboxyl COO bonding peak decreased with W/FM factor, and the tendency of intensity change of carboxylic COO peak was contrary to those of ether C-O and carbonyl C=O peaks.