• 제목/요약/키워드: N,N'-dimethylformamide

검색결과 196건 처리시간 0.027초

Halolactonization reaction using N-haloimides

  • Cook, Chae-Ho;Cho, Youn-Sang;Jew, Sang-sup;Suh, Young-Guh;Kang, Eung-Ku
    • Archives of Pharmacal Research
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    • 제6권1호
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    • pp.45-53
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    • 1983
  • Novel halactolactonizations using NBS (2), NIS(3), and NSP(4) in dry DMF were found to be the most reasonable and efficient procedures. The participation of X as the cylization initiator could be clarly rationalized by experimental results and the regioselectivities of formed halolactones were reasonably elucidated by weakly bridged carbonium ion intermediate.

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이산화탄소와 디메틸포름아마이드 혼합물의 기포점 측정 및 모델링 (Measurement and Modeling of Bubble Points for Binary Mixtures of Carbon Dioxide and N,N-Dimethylformamide)

  • 정준영;이병철
    • 청정기술
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    • 제17권1호
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    • pp.19-24
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    • 2011
  • 본 연구에서는 가변부피 투시창이 설치되어 있는 고압 상평형 측정 장치를 사용하여 이산화탄소의 임계온도 이상과 디메틸포름아마이드(DMF)의 임계온도 이하의 온도 범위에서 혼합물의 조성을 변화시키면서 이산화탄소와 디메틸포름아마이드 혼합물의 기포점 압력을 측정하였다. 실험적으로 측정된 기포점 압력 데이터를 Peng-Robinson 상태방정식에 상관시킴으로써 기포점 조성과 평형을 이루는 이슬점 조성을 추정하였다. 실험적으로 측정된 기포점 압력은 Peng-Robinson 상태방정식으로 계산한 결과와 매우 잘 일치하였다. 가변부피 투시창이 설치되어 있는 고압 상평형 실험장치는 고압의 압축유체 혼합물의 기포점을 매우 쉽고 빠르게 측정할 수 있는 방법이라고 할 수 있다.

Intermolecular Hydrogen Bonding and Vibrational Analysis of N,N-Dimethylformamide Hexamer Cluster

  • Park, Sun-Kyung;Min, Kyung-Chul;Lee, Choong-Keun;Hong, Soon-Kang;Kim, Yun-Soo;Lee, Nam-Soo
    • Bulletin of the Korean Chemical Society
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    • 제30권11호
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    • pp.2595-2602
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    • 2009
  • Hexamer cluster of N,N-dimethylformamide(DMF) based on the crystal structure was investigated for the equilibrium structure, the stabilization energies, and the vibrational properties in the density functional force field. The geometry (point group $C_i$) of fully optimized hexamer clustered DMF shows quite close similarity to the crystal structure weakly intermolecular hydrogen bonded each other. Stretching force constants for intermolecular hydrogen bonded methyl and formyl hydrogen atoms with nearby oxygen atom, methyl C–H${\cdots}$O and formyl C–H${\cdots}$O, were obtained in 0.055 $\sim$ 0.11 and $\sim$ 0.081 mdyn/$\AA$, respectively. In-plane bending force constants for hydrogen bonded methyl hydrogen atoms were in 0.25 $\sim$ 0.33, and for formyl hydrogen $\sim$ 0.55 mdynÅ. Torsion force constants through hydrogen bonding for methyl hydrogen atoms were in 0.038 $\sim$ 0.089, and for formyl hydrogen atom $\sim$ 0.095 mdynÅ. Calculated Raman and infrared spectral features of single and hexamer cluster represent well the experimental spectra of DMF obtained in the liquid state. Noncoincidence between IR and Raman frequency positions of stretching C=O, formyl C–H and other several modes was interpreted in terms of the intermolecular vibrational coupling in the condensed phase.

폴리우레탄 코팅장갑내의 DMF 함량 및 피부노출에 대한 평가 (Concentrations of N,N-dimethylformamide in Polyurethane Gloves and Risk Assessment for Dermal Exposures)

  • 박해동;노지원
    • 한국산업보건학회지
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    • 제32권2호
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    • pp.102-110
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    • 2022
  • Objectives: The purpose of this study is to analyze the content of N,N-dimethylformamide(DMF) in polyurethane coated gloves(PU-gloves) and to assess the dermal exposure generated by wearing them. Methods: We analyzed the concentrations of DMF in 12 gloves by EN16778 standard. The samples cut into pieces of about 10 by 10 mm and extracted with methanol in flask in an ultrasonic bath at 70℃. An aliquot of the extract is analyzed with GC-MS. The dose of dermal exposure was calculated by ECETOC TRA consumer 3.1 and compared with derived no effect level(DNEL) for systemic effects due to long term exposure by workers. The extracted amount of DMF by saline solution was compared with that by EN16778 standard. Results: The mean concentration of DMF in PU-gloves was 1,377 mg/kg(range 13~3,948 mg/kg). The concentration of DMF showed significantly differences by packing type, manufacturer, and price(p<0.05). The dose of dermal exposure was 0.0007~0.572 mg/kg body weight/day when the DMF content was 10~4,000 mg/kg. The DMF extracted by saline solution was around 11% for 8 hours. Conclusions: The risk of dermal exposure due to the residual DMF in the PU-gloves was not signifiant. But, the limit of 1,000 mg/kg in PU-gloves can be recommended for international standard and trading systems.

디메틸포름아마이드 용매와 초임계 이산화탄소 역용매를 사용한 RDX 고에너지 물질의 재결정 (Recrystallization of RDX High Energy Material Using N,N-Dimethylformamide Solvent and Supercritical $CO_2$ Antisolvent)

  • 김창기;이병철;이윤우;김현수
    • 청정기술
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    • 제15권4호
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    • pp.233-238
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    • 2009
  • 초임계유체공정은 고폭화약이나 추진제로 사용되는 고에너지 물질을 미세입자로 제조하기 위한 새롭고 환경친화적인 방법으로 큰 관심을 받아 왔다. 본 연구에서는 고폭화약 대상물질로서 RDX(cyclotrirnethylenetrinitramine)을 선정하여 초임계역용매 재결정공정을 이용하여 RDX를 미세입자로 제조하는 연구를 수행하였다. 제조된 입자의 크기와 형상에 미치는 초임계공정 운전변수의 영향을 관찰하였다. 본 연구에서는 RDX를 용해시키기 위한 유기용매로 N,N-dimethylformamide를 사용하였다. 초임계역용매 재결정공정에 의해 RDX 입자들의 크기는 $10\;{\mu}m$ 이하로 뚜렷하게 감소하였다. 본 연구에서 설정한 공정변수의 범위에서 재결정되는 RDX 입자들의 크기를 관찰한 결과, 313.15K, 150 bar, 그리고 주입용액에서의 RDX의 농도가 15wt%일 때 가장 작은 RDX 입자가 재결정되었다.