• Title/Summary/Keyword: dimethylformamide

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A Study on the Insecticidal and Antibacterial Activity of the Carbamate derivatives (Carbamate 화합물의 殺蟲效果 및 抗菌力에 관한 연구)

  • Kang, Hoe-Yang;Jung, Chan
    • Journal of Environmental Health Sciences
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    • v.23 no.1
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    • pp.62-65
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    • 1997
  • The insecticidal and antibacterial activity of new synthesized carbamate derivatives(5,7-dibromo-8-hydroxyquinolinyl-N-methylcarbamate(I), 5,7-dibromo-8-hydroxyquinolinyl-N-ethylcarbamate(II)) was examined using 0.2w/v% acetone solutions and 50 $\mu$g/ml-1000 $\mu$g/ml N,N'-dimethylformamide H$_2$O(2:3) solutions of each compounds, respectively. 1. Two carbamates exerted insectiddal effects on Sogata furcifera HORVATH, Delphacodes Striatella FAUEN and Nilaparvate lugens STAL, Whereas no significant effects were observed on the Inazuma dorasalis MOISCHIULSKY Nephateffix apicalis Cincticeps UHLER. 2. These compounds exhibited growth-inhibitory activity against Staphyloccus aureus, Salmonella paratyphi A, Shigella dysenteriae 1a, Escherichia coli NL 1401, at the concentration range of 100-500 $\mu$g/ml in general.

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Expression of Latent P-Type ATPases and Their Presumptive Roles in Cell Membrane of Helicobacter pylori

  • YUN, SOON-KYU;SE-YOUNG HWANG
    • Journal of Microbiology and Biotechnology
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    • v.7 no.6
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    • pp.378-385
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    • 1997
  • Cation motive ATPases on cell membranes of Helicobacter pylori were investigated using everted membrane vesicles. Latent ATPases could be ascertained from aggregated vesicle using N, N-dimethylformamide (DMF) and Triton X-100. By contrast, ultrasonication or chloroform treatments caused membranes to be disrupted, resulting in an alteration of sensitivities against azide or vanadate. Considerable amounts of vanadate-sensitive enzymes were identified from vesicle micelles, prepared by the dilution method. These were activated in the presence of either $Ni^{2+}\;or\;NH_4^+$. From studies employing H. pylori intact cell systems, we found that ATPase expression of this bacterium was markedly dependent upon air composition. It was interesting that cellular expression of $Ni^{2+}$- or $NH_4^{+}$-motive ATPases was significantly affected by extracellular pH, suggesting that these unique enzymes may physiologically be involved in cellular $Ni^2$ import and $NH_4^+$ export, respectively.

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Studies on Microbial Transformation of Meloxicam by Fungi

  • Shyam Prasad, G.;Girisham, S.;Reddy, S.M.
    • Journal of Microbiology and Biotechnology
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    • v.19 no.9
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    • pp.922-931
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    • 2009
  • Screening-scale studies were performed with 26 fungal cultures for their ability to transform the anti-inflammatory drug meloxicam. Among the different fungi screened, a filamentous fungus, Cunninghamella blakesleeana NCIM 687, transformed meloxicam to three metabolites in significant quantities. The transformation of meloxicam was confirmed by high-performance liquid chromatography (HPLC). Based on the liquid chromatography-tandem mass spectrometry (LC-MS/MS) data, two metabolites were predicted to be 5-hydroxymethyl meloxicam and 5-carboxy meloxicam, the major mammalian metabolites reported previously. A new metabolite was produced, which is not detected in mammalian systems. Glucose medium, pH of 6.0, temperature of $27^{\circ}C$, 5-day incubation period, dimethylformamide as solvent, and glucose concentration of 2.0% were found to be suitable for maximum transformation of meloxicam when studied separately. It is concluded that C. blakesleeana can be employed for biotransformation of drugs for production of novel metabolites.

Studies on The Influence of The Polarity of The Spreading Solvent on The Properties of The Polymer Monolayers on The Water Surface (분산용매의 극성 변화가 수면 위 고분자 단층막의 성질에 미치는 영향에 관한 연구)

  • Suh, Hye-Ran;Kim, Eu-Gene
    • Journal of the Korean Applied Science and Technology
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    • v.17 no.1
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    • pp.23-28
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    • 2000
  • The influence of the polarity of the spreading solvent on the properties of the monolayer of poly(styrene-co-acrylonitrile)'s with various acrylonitrile contents was studied. The surface pressure - area isotherm and the apparent dipole moment - area isotherm were obtained and analyzed when the mixtures of methylene chloride and N-N-dimethylformamide used as spreading solvent. The isotherms were strongly influenced by the polarity of the solvent.

Synthesis of N,N-Dimethylacetamide from Carbonylation of Trimethylamine by Rhodium(I) Complex Under Anhydrous Condition

  • Hong, Jang-Hwan
    • Journal of Integrative Natural Science
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    • v.8 no.4
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    • pp.235-243
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    • 2015
  • Rhodium(I)-complex of $[Rh(CO)_2I_2{^-}]$ catalyzed carbonylation of anhydrous-trimethylamine in the presence of methyl iodide to give DMAC (N,N-dimethylacetamide) in no solvent. The catalyst had been reused 20 times, the analyses and distillation of collected products showed that the yields of DMAC, MAA (N-methylacetamide), and DMF (N,N-dimethylformamide) were 82.3%, 12.6%, and 4.4%. The conversion rate of trimethylamine was 99 % and the selectivity of DMAC was 82.3% with TON (Turnover Number) of 700. Stepwise procedure of inner-sphere reductive elimination for the formation of DMAC was suggested instead of acyl iodide intermediate.

Preparation and Nonlinear Optical Properties of Novel Polyesters with Enhanced Thermal Stability of Second Harmonic Generation

  • Kim, Jin-Hyang;Won, Dong-Seon;Lee, Ju-Yeon
    • Bulletin of the Korean Chemical Society
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    • v.29 no.1
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    • pp.181-186
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    • 2008
  • 2,5-Di-(2'-hydroxyethoxy)-4'-nitrostilbene (3) was prepared and polycondensed with terephthaloyl chloride, adipoyl chloride, and sebacoyl chloride to yield novel T-type polyesters (4-6) containing the NLO-chromophores dioxynitrostilbenyl groups, which constituted parts of the polymer backbones. Polymers 4-6 are soluble in common organic solvents such as acetone and N,N-dimethylformamide. They showed thermal stability up to 260 oC in thermogravimetric analysis with glass-transition temperatures obtained from differential scanning calorimetry in the range 90-95 oC. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at the 1064 nm fundamental wavelength were around 1.42 ´ 10-9 esu. The dipole alignment exhibited high thermal stability up to 5 oC higher than glass-transition temperature (Tg), and there was no SHG decay below 100 oC due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

Theoretical Mechanism Studies on the Enantioselectivity of aza-MBH-type Reaction of Nitroalkene to N-tosylimine Catalyzed by Thiourea-tertiary Amine

  • Lu, Nan;Wang, Huatian;Wang, Yangping
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3591-3596
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    • 2013
  • The enantioselective aza-Morita Baylis Hillman reaction of nitroalkene and N-tosylimine catalyzed by thiourea-tertiary amine has been investigated using density functional theory. Enantioselectivity is dominated by the cooperative effect of non-covalent and weak covalent interactions imposed by different units of catalyst. As Lewis base, the tertiary amine unit activates nitroalkene via weak covalent bond. The weak covalent interaction orients the reaction in a major path with smaller variations of this bond. The aromatic ring unit activates N-tosylimine via ${\pi}-{\pi}$ stacking. The non-covalent interaction selects the major path with smaller changes of the efficient packing areas. Thiourea unit donates more compact H-bonded network for species of the major path. The calculated ee value in xylene solution phase (97.6%) is much higher than that in N,N-Dimethylformamide (27.2%). Our conclusion is also supported by NBO analysis.

Studies on 1-Isonicotinoyl-2-furfurylidene hydrazine-Cu(II) Complex Compound. (1-Isonicotinoyl-2-furfurylidene Hydrazine-Cu(II) 착화합물에 관한 분석화학적연구)

  • 백남호;최윤수
    • YAKHAK HOEJI
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    • v.9 no.1_2
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    • pp.18-22
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    • 1965
  • A new organic reagent, 1-isonicotinoyl-2-furfurylidene hydrazine was synthesized from isonicotinic acid hydrazide and furfural, gives precipitate with copper(II), mercury(II) and argent(I), whereas, it gives a water soluble yellow complex with iron(III). Copper complex of the reagent is soluble in EtOH MtOH, pyridine, dioxane and dimethylformamide with green yellow coloration. The complex has a maximum absorption at 385 m.$\mu$ and molar ratio of copper; reagent was estimated as 1:1 by continuous variation method, slop method and chelate titration method. Molar extinction coefficient (9600) and apparant formation constant of this complex was spectrophotometrically determined. K=1.7 * $10^{7}$ (Babko's method) K=2.1 * $10^{7}$ (Anderson's method). This reagent reacted with copper so sensitive that it would be available for determination of Cu (II).

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Melting and Melt Viscosity Behavior of Wet-PAN Systems (물을 함유한 아크릴 중합체의 용융 및 용유점도 거동)

  • 오세천
    • The Korean Journal of Rheology
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    • v.5 no.2
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    • pp.136-143
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    • 1993
  • PDSC(pressurized differential scanning calorimeter)를 이용하여 물 또는 물 -DMF(N,N-dimethylformamide) 혼합물을 함유한 아크릴로니크릴 중합체(wet-PAN)의 융점 거동을 조사하였으며 wet-PAN 용융체의 점도측정에 적합한 모세관형 점도계를 제작하여 전단속도 및 온도에 따른 점도변화를 고찰하였다. 물에 의한 wet-PAN의 융점 및 용융점도 는 물의 함량이 증가함에 따라 점근적으로 감소하여 25wt% 이상에서는 거의 일정하였다. 또한 물(25wt% 기준)의 일부를 DMF로 대체하였을 경우에는 융점이 감소하였다. 한편 wet-PAN의 용융점도는 power-law 거동에 준하였으며 물계에서는 power-law 지수(n)가 0.16(19$0^{\circ}C$)~0.18(17$0^{\circ}C$)인데 비하여 물(95)~DMF(5) 혼합물계에서는 0.24(175$^{\circ}C$)~0.25(16 5$^{\circ}C$)로서 점도의 전단담화거동이 약해졌으나 흐름의 활성화에너지는 다소 증가 하였다.

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Novel P(VDF-TrFE) Polymer Electrolytes: Their Use in High-Efficiency, All-Solid-State Electrochemical Capacitors Using ZnO Nanowires

  • Park, Young Jun;Bae, Joonho
    • Journal of Electrochemical Science and Technology
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    • v.9 no.2
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    • pp.126-132
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    • 2018
  • For the first time, an innovative approach using P(VDF-TrFE) as a polymer electrolyte for high efficiency, all-solid-state supercapacitors is presented. The polymer electrolyte was successfully achieved by dissolving P(VDF-TrFE) copolymers in dimethylformamide (DMF). Thermal analysis and infrared spectroscopy revealed excellent thermal stability up to $400^{\circ}C$ and copolymer's interaction with DMF. Electrochemical capacitors fabricated using P(VDF-TrFE) in DMF and ZnO NWs demonstrated high capacitive performance. Furthermore, the gel electrolyte-based supercapacitors demonstrated excellent mechanical durability up to a bend angle of $120^{\circ}$. Novel P(VDF-TrFE) electrolytes could be a promising approach for applications in flexible, fabric-based, and high-efficiency energy devices.