• Title/Summary/Keyword: Dimethyl sulfate

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On the Electrochemical Reduction of O, O-Dimethyl-O-(3-Methyl-4-Nitrophenyl)-Phosphorthioate (Fenitrothion) Pesticide in Acetonitrile Solution (Acetonitrile 용액중에서 살충제 O, O-Dimethyl-O-(3-Methyl-4-Nitrophenyl)-Phosphorothioate (Fenitrothion)의 전기화학적 환원)

  • Il-Kwang Kim;Youn-Geun Kim;Hyun-Ja Chun
    • Journal of the Korean Chemical Society
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    • v.32 no.3
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    • pp.186-194
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    • 1988
  • 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 partially reversible 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)-phosphorothioate which undergoes single 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.

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Methylation Methods on Identification of Phenolics in Chebulae Fructus (Chebulae Fructus중 페놀 물질 확인시의 Methylation법 비교)

  • 김정숙
    • Journal of the East Asian Society of Dietary Life
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    • v.4 no.1
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    • pp.79-86
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    • 1994
  • Food quality in food processing and storage were affected by the kinds of phenolics involved. To analyze phenolics of Chebulae Fructus by the way of GC-MSm methylation and trimethylsilyation(TMS) are necessary. The methods of methylation were dimethyl sulfate method and diazomethane method. so this study was undertaken to research the better methylation method before measuring GC-MS. But dimethyl sulfate method of methylation was not sufficient to analyze phenolics. So the phenolics of Chebulae Fructus were analyzed by the diazomethane methylation method and TMS with the pyridine, N-O-bis-trimethylsilyl-acetamide(BSTFA) and trimethylchlorosilane(TMCS). With the exception of pyrogallol and phloroglucinol in insoluble phenolics of Chebulae Fructus, the greater part of phenolics. analysis could be analyzed by GC-MS in company with diazomethane methylation method and TMS.

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Antibacterial Sulfated Alkene from a Tunicate, Styela clava

  • Yun, So-Mi;Jang, Jun-Ho;Ryu, Ji-Eun;Choi, Byeong-Dae;Lee, Jong-Soo
    • Natural Product Sciences
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    • v.13 no.2
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    • pp.132-134
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    • 2007
  • An analog of antibacterial sulfated alkene against Bacillus subtilis was isolated from a species of tunicate (Mideoduck), Styela clava, cultured at Jindong Bay, Korea. The structure was determined as 4,8-dimethyl-3-nonenyl sulfate by MS and spectral analysis such as UV IR and NMR.

RNase Resistant RNA in the Egg of Xenopus laevis: I. RNA Extraction and in Vitro Labeling

  • Chung, Hae-Moon
    • The Korean Journal of Zoology
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    • v.20 no.1
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    • pp.9-18
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    • 1977
  • RNA was extracted from the eggs of Xenopus laevis to do preliminary experiments before testing the possibility that if RNase resistant RNA molecules exist in the amphibian egg. Chromatography on Sephadex G-100 column indicated 3 peaks consistently. Only high molecular weight RNA species eluted in the first peak were labeled in vitro using $^{3}H$-dimethyl sulfate to eliminate the possible contribution of base paired oligonucleotides from tRNA. By this method, high specific activity could be obtained and the attached methyl groups were quite stable.

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Synthesis and Antistatic Property of Acryl Urethane Polymer (아크릴우레탄 폴리머의 합성과 대전방지특성)

  • Hong, Kyung-Ho;Jeong, Noh-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.26 no.1
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    • pp.93-101
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    • 2009
  • Antistatic acrylic resin is made from n-butyl methacrylate, methyl methacrylate, dimethyl amino ethyl methacrylate(DMAEMA), 2-ethyl hexyl methacrylate, hydroxy ethyl methacrylate, 2,2'-azobis iso-butyronitrile by synthesis. To achieve a lowest surface resistance of antistatic acrylic resin was applied to a variety of synthesis processes. The acrylic resin has been determined from the value of surface resistance and -then the antistatic acrylic resin including dimethyl amino ethyl methacrylate of the 10%, 20% and 30% is synthesized. Finally, dimethyl sulfate(DMS) on a variety of weight ratios is added to antistatic acrylic resin. When DMAEMA / DMS weight ratio is 1/1, antistatic acrylic resin isn't haze the lower the surface resistance. Compared to the traditional antistatic agent, all aspects of the physical properties is outstanding.

Removal of Dimethyl Sulfide in Ceramic Biofilters Immobilized with Thiobacillus thioparus TK-m

  • Kim, Jong-Yeon;Kim, Byung-Woo
    • Journal of Microbiology and Biotechnology
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    • v.13 no.6
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    • pp.866-871
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    • 2003
  • Malodorous gas of dimethyl sulfide (DMS) was biologically oxidized to sulfate by Thiobacillus thioparus TK-m (DSM5368) immobilized in/on ceramic beads. More than 99.99% of DMS removal efficiency was obtained in a ceramic-biofilter reactor of 3.91 when the feed concentrations were about 27.5 and 55.0 mg DMS/1 at $30^{circ}C$. However, the removal efficiency of the biofilter at above $40^{circ}C$ decreased to 4.5 mg DMS/(lㆍmin) which was 85% of that at $30^{circ}C$.

S$_H$2 Reaction on Silicon-Carbon Bond in the Photoreactions of 2, 3-Benzo-1, 1-diphenyl(or dimethyl)-1-sila-2-cyclobutene with Carbonyl Compounds

  • Kang, Kyung-Tai;Okazaki, Renji;Inamoto, Naoki
    • Bulletin of the Korean Chemical Society
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    • v.5 no.1
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    • pp.32-37
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    • 1984
  • The photoreaction of 2, 3-benzo-1, 1-diphenyl (or dimethyl)-1-sila-2-cyclobutene (9 or 10) with an aldehyde or ketone results in 1:1 cycloadduct of [4 + 2] type. In the reactions of 2, 3-benzo-1, 1-dimethyl-1-sila-2-cyclobutene (10) with acetone and butanone, another 1:1 adducts (13) were also formed, respectively. The following facts indicate that the formation of adduct involves an attack of a triplet carbonyl compound on the silicon of the benzosilacyclobutene, an $S_H2$ process. (1) Even when the reaction of 9 with acetophenone was carried out under conditions such that more than 99% of incident light was absorbed only by acetophenone using the filter solution of aq. cupric sulfate, the same adduct was still formed. (2) When the reaction of 9 with acetone was carried out under oxygen atmosphere, only trace amount of adduct was formed.

Effect of Sulfate-based Cathode-Electrolyte Interphases on Electrochemical Performance of Ni-rich Cathode Material

  • Chae, Bum-Jin;Song, Hye Ji;Mun, Junyoung;Yim, Taeeun
    • Journal of Electrochemical Science and Technology
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    • v.11 no.4
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    • pp.361-367
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    • 2020
  • Recently, layered nickel-rich cathode materials (NCM) have attracted considerable attention as advanced alternative cathode materials for use in lithium-ion batteries (LIBs). However, their inferior surface stability that gives rise to rapid fading of cycling performance is a significant drawback. This paper proposes a simple and convenient coating method that improves the surface stability of NCM using sulfate-based solvents that create artificial cathode-electrolyte interphases (CEI) on the NCM surface. SOx-based artificial CEI layer is successfully coated on the surface of the NCM through a wet-coating process that uses dimethyl sulfone (DMS) and dimethyl sulfoxide (DMSO) as liquid precursors. It is found that the SOx-based artificial CEI layer is well developed on the surface of NCM with a thickness of a few nanometers, and it does not degrade the layered structure of NCM. In cycling performance tests, cells with DMS- or DMSO-modified NCM811 cathodes exhibited improved specific capacity retention at room temperature as well as at high temperature (DMS-NCM811: 99.4%, DMSO-NCM811: 88.6%, and NCM811: 78.4%), as the SOx-based artificial CEI layer effectively suppresses undesired surface reactions such as electrolyte decomposition.