• Title/Summary/Keyword: 2-diamine

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Sonolytical Decomposition of NHCs in Aqueous Solution (수계중 이환형 질소고리화합물(NHCs)의 초음파적 분해)

  • Yoo, Young-Eok;Maeda, Yasuaki
    • Journal of Environmental Science International
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    • v.16 no.4
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    • pp.393-397
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    • 2007
  • The sonolytic decomposition of NHCs(Nitrogen Heterocyclic Compounds), such as atrazine[6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine], simazine(6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N'-triethyl-1,3, 5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range $1.06{\sim}2.07({\times}10^{-2}min^{-1})$ under air and $1.30{\sim}2.59({\times}10^{-2}min^{-1})$ under argon at a concentration of $200{\mu}M$ of NHCs. The rate of hydroxyl radicals(${\bullet}{OH}$) formation from water is $19.8{\mu}M\;min^{-1}$ under argon and $14.7{\mu}M\;min^{-1}$ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ${\bullet}{OH}$ radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ${\bullet}{OH}$ radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent $[Fe^{2+}]$ accelerates the decomposition. This is probably due to the regeneration of ${\bullet}{OH}$ radicals from hydrogen peroxide, which would be formed from recombination of ${\bullet}{OH}$ radicals and which may contribute a little to the decomposition.

Volatile Organic Compounds(VOCs) Sensing Properties of Thin Films Based on Copper phthalocyanine and Dilithium phthalocyanine Compounds (Copper phthalocyanine과 Dilithium phthalocyanine 화합물 박막의 휘발성 유기화합물(VOCs) 센서 특성)

  • Kim, Dong Hyun;Kang, Young Goo;Kang, Young Jin
    • Journal of the Korean Society of Safety
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    • v.28 no.2
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    • pp.37-41
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    • 2013
  • In this work, we report the effect on the volatole organic compounds(VOCs) sensing properties of Copper phthalocyanine(CoPc) and Dilithium phthalocyanine(DiLiPc) thin films onto alumina substrates. Use evaporation method and the spin-coated method for sensing device. The materials of metallophthalocyanine macrocyclic compound solutions blended with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] solutions. The influence of the blended in with metallophthalocyanine macrocyclic compounds on the resistance have been measured and analyzed in five different volatole organic compounds. The following results were obtained: The AFM 3D image of thin films deposited on metallophthalocyanine macrocyclic compound shows that the surfaces roughness were about CuPc 4.1~14.3 nm(7.5~8.1%), DiLiPc 10.3~22.2 nm(7.9~11.5%). The resistances decreases upon increasing the concentration of vapor organic compounds to CuPc and DiLiPc thin films. That thin films blended Copper phthalocyanine(CoPc) and Dilithium phthalocyanine(DiLiPc) with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy--5-(2'-ethylhexyloxy)-1,4-phenylenevinylene]. The resistances of blended thin films with N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine and/or Poly[2-methoxy--5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] decreases upon increasing the concentration of volatole organic compounds(VOCs) on DiLiPc than CuPc compound thin films.

Decomposition of Nitogen Heterocyclic Compounds(NHCs) in Aqueous Solution by Sonication

  • Yoo, Young-Eok;Maeda, Yasuaki
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11a
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    • pp.171-176
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    • 2003
  • The sonolytic decomposition of NHCs, such as atrazine[6-chloro-N-ethyl-N' -(1-methylethyl)-1,3,5-triazine-2,4-diamine], simazine( 6-chloro-N,N' -diethyl-l ,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N'-triethyl-l,3,5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range 1.06∼2.07 (x10/sup -3/ min/sup -1/) under air and 1.30∼2.59(x10/sup -3/ min/sup -1/)under argon at a concentration of 200μM of NHCs. The rate of hydroxyl radicals(·OH) formation from water is 19.8μM min/sup -1/ under argon and 14.7 μM min/sup -1/ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ·OH radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ·OH radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent [Fe/sup 2+/] accelerates the decomposition. This is probably due to the regeneration of ·OH radicals from hydrogen peroxide, which would be formed from recombination of ·OH radicals and which may contribute a little to the decomposition.

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Surface Roughness of Dentin and Formation of Early Cariogenic Biofilm after Silver Diamine Fluoride and Potassium Iodide Application (Silver Diamine Fluoride와 요오드화 칼륨 도포 후 상아질 표면 거칠기와 초기 우식원성 세균막 형성)

  • Haeni, Kim;Howon, Park;Juhyun, Lee;Siyoung, Lee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.49 no.2
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    • pp.140-148
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    • 2022
  • This study aimed to evaluate the effect of silver diamine fluoride (SDF) and potassium iodide (KI) on the formation of cariogenic biofilm and surface roughness in vitro. A total of 48 bovine dentin specimens with artificially induced caries were prepared and divided into 3 groups of 16: untreated control, SDF-treated, and SDF-treated followed by KI (SDFKI). Ten specimens from each group were used to observe microbial adhesion. Multispecies cariogenic biofilms including Streptococcus mutans, Lactobacillus casei, and Candida albicans were cultured on the specimens. Microbes were cultured for 24 hours, and the colony-forming unit was calculated. The remaining specimens were observed by atomic force microscope and scanning electron microscope (SEM). The number of bacteria was significantly lower in the SDF and SDFKI groups. KI did not inhibit the antibacterial activity of SDF significantly. SEM images showed particles generated after SDF and SDFKI application were deposited on the dentin, but there was no significant difference in surface roughness between the 3 groups. This study confirmed that SDF and SDFKI application did not have a significant effect on the surface roughness of dentin, but effectively inhibited the formation of the early cariogenic bacterial film after 24 hours compared to the control.

Regioselective Synthesis of Heterocyclic Ketene N,N-, N,O- and N,S-acetals in Aqueous Medium

  • Chanu, Langpoklakpam Gellina;Singh, Okram Mukherjee;Jang, Sang-Hun;Lee, Sang-Gyeong
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.859-862
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    • 2010
  • The reactions of ketene dithioacetals with ethane-1,2-diamine, propane-1,3-diamine, 2-aminoethanol, 3-aminopropanol, and 2-aminoethanethiol in ordinary water in the absence of any acid/base catalyst afforded the heterocyclic ketene N,N-, N,O- and N,S-acetals in good yields.

Antimicrobial Persistence of Silver Diamine Fluoride and Silver Fluoride against Streptococcus mutans

  • Hyeon-Jin Kim;So-Youn An
    • Journal of Korean Dental Science
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    • v.16 no.2
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    • pp.164-171
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    • 2023
  • Purpose: To evaluate the antimicrobial persistence of silver diamine fluoride (SDF) and silver fluoride (AgF) on Streptococcus mutans. Materials and Methods: An in vitro experiment was conducted to observe changes in the diameter of the inhibition zone of various materials, including AgF (Riva Star AquaTM step 1; SDI), potassium iodine (Riva star aquaTM step 2; SDI), Fluor protector® (FP, Ivoclar Vivadent), SDF (Riva starTM step 1; SDI), Ampicillin (Sigma-Aldrich), Amphotericin B (Nexstar) and negative control on S. mutans. Result: SDF, AgF and FP exhibited significant antimicrobial persistence over the 4 weeks period (P<0.05). At day 28, the diameter of inhibition zone was larger in SDF than in AgF. Conclusion: SDF and AgF have significant antibacterial durability against bacteria commonly associated with dental caries, with the antimicrobial effect lasting for at least 4 weeks. Further clinical studies are needed to validate these findings in vivo.

Preparation and Characterization of Polyamide Thin Film Composite Reverse Osmosis Membranes Using Hydrophilic Treated Microporous Supports (친수성 처리된 다공성 지지체를 이용한 폴리아마이드 박막 역삼투 복합막 제조 및 특성 분석)

  • Son, Seung Hee;Jegal, Jonggeon
    • Membrane Journal
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    • v.24 no.4
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    • pp.317-324
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    • 2014
  • It is very well known that the conventional polyamide (PA) thin film composite (TFC) reverse osmosis (RO) membranes have excellent permselective properties, but their chlorine tolerance is not good enough. In this study, to improve such chlorine tolerance, microporous membranes containing hydrophilic functional groups such as -COOH were used as a support to prepare PA TFC RO membranes, employing the conventional interfacial polymerization method. Meta-phenylene diamine (MPD) and 2,6-diamine toluene (2,6-DAT) were used as diamine monomers and tri-mesoyl chloride (TMC) as an acid monomer. The membranes prepared were characterized using various instrumental analytical methods and permeation test set-up. The flux obtained from the membranes prepared so was more than $1.0m^3/m^2day$ at 800 psi of operating pressure, while the salt rejection was over 99.0%. The chlorine tolerance of them was also found to be better than that of the membrane prepared by using conventional polysulfone support without hydrophilic functional groups.

Studies on the Complexes of Lanthanide ion with Multidentate Ligand (I). Determination of Thermodynamic Parameters with Solution Calorimetric Method in Nonaqueous Solvents (란탄족 원소의 여러자리 리간드 착물에 관한 연구 (제 1 보) 물아닌 용액에서 용액열량계에 의한 열역학적 함수결정)

  • Sam-Woo Kang;Won-Hae Koo;Soo-Min Lee;Chang Choo-Hwan;Moo-Yol Seo
    • Journal of the Korean Chemical Society
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    • v.33 no.6
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    • pp.588-595
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    • 1989
  • Log K, ${\Delta}$H and ${\Delta}$S for the complexation of $La^{3+},\;Ce^{3+}$ and $Eu^{3+}$with various multidentate ligand containing crown ether, diaza crown ether and diamine ether have been determined in methanol and acetonitril solutions at $25^{\circ}C$ by solution calorimetric titration method. The greater stability constant of $La^{3+}$-15C5 than those of 18C6 diaza [2.2] in methanol are discussed in terms of the size of metal ion and the ligand cavity and of metal ion solvation. The stabilities of $Ce^{3+}$ and $La^{3+}$ ion complexes with a various multidentate ligand in acetonitril are in the order of (diamine ether)<18C6<15C5$Ce^{3+}$, $La^{3+}$ and $Eu^{3+}$-diaza [2.2] complexes in acetonitril are increased with the following order: $Eu^{3+}$ < $La^{3+}$ < $Ce^{3+}$, that is increasing order of the optimum size and of the charge density of metal ion.

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Alignment of smectic liquid crystals on newly synthesized photo-reactive polyimide with chalcone moiety

  • Song, Dong-Mee;Shin, Dong-Myung;Kim, Jae-Hoon;Kim, Il
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.479-482
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    • 2002
  • Benzylideneacetophenones are known as chalcones[1]. The chalcone has been known to be a photo-isomerizable and photo-dimerizable chromophore. The chalcone derivatives were prepared by base-catalyzed condensation of aldehydes and acetophenones, which were substituted with various alkyl chains. The synthesized chalcone was introduced into the t-BOC protected diamine through William synthesis reaction. Photocrosslinkable polyimide was prepared via one-step imidization reaction of DOCDA (5-(2,5-dioxotetrahydro furyl}-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride) and the chalcone introduced diamine using isoquinoline (5 wt%) in m-cresol. The polyimide solutions were spin-coated onto the quartz, silicone wafer and glass substrates and the obtained thin films were irradiated obliquely with linearly polarized UV light.

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