• 제목/요약/키워드: carbonyl

검색결과 1,116건 처리시간 0.019초

알켄-오존 반응의 중간 생성물에 대한 ab initio 양자역학적 고찰 (Quantum Mechanical Investigation on the Intermediates of Alkene-Ozone Reaction)

  • 강창덕;김승준
    • 대한화학회지
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    • 제42권2호
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    • pp.161-171
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    • 1998
  • 알켄-오존 반응에서 생성된 중간 생성물로써 primary ozonide (POZ),secondary ozonide (SOZ)그리고 carbonyl oxide의 분자구조, vibrational frequencies그리고 infrared(IR)스펙트럼의 세기 등에 대한 이론적 연구를 high level ab initio 양자역학적 방법(CISD,CCSD)을 사용하여 수행하였다. 일반적으로, polarization function은 결합각과 결합길이를 감소시키는 경향을 보였고 반면, electron correlation effect는 결합길이와 결합각을 약간 증가시키는 경향을 보이고 있다. Carbonyl oxide의 분자구조는 zwitterionic form이 diradical form보다 더 안정한 것으로 예측되었으며, 두 형태의 에너지는 차이는 TZ2P CISD level에서 약 22.4 kcal/mol인 것으로 계산되었다. 또한, POZ과 SOZ의 분자구조 및 harmonic vibrational frequencies들을 실험결과와 비교 분석하였으며 IR세기에 근거하여 각 vibrational mode를 assign 하였다.

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Selective Reduction of Carbonyl Compounds with B-Acetoxy- and B-Trifluoroacetoxydiisopinocampheylboranes

  • Cha, Jin-Soon;Nam, Ho-Tae;Park, Seung-Jin;Kwon, Sang-Yong;Kwon, Oh Oun
    • Bulletin of the Korean Chemical Society
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    • 제27권5호
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    • pp.667-671
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    • 2006
  • The new MPV-type reagents, B-acetoxydiisopinocampheylborane ($Ipc _2$BOAc) and B-trifluoroacetoxydiisopinocampheylborane $(Ipc _2BO _2CCF _3)$, have been prepared and their reducing characteristics in the reduction of carbonyl compound have been examined in order to find out a new reducing system with unique applicability in organic synthesis. In general, the reactivity of $Ipc _2BO _2CCF _3$ appears to be stronger than that of $Ipc _2$BOAc, presumably due to the acidity increase by the electron-withdrawing fluorine-substituent. Both reagents show an excellent selectivity in 1,2-reduction of $\alpha,\beta$-unsaturatedcarbonyl compounds and in competitive reduction between structurally different carbonyl compounds. In addition, $Ipc _2BO _2CCF _3$ shows interesting features in the stereoreduction of cyclic ketones.

방사선(放射線) 조사(照射)가 감자 괴경(塊莖)의 치유조직형성(治癒組織形成), Solanine 함량(含量) 및 Carbonyl 화합물(化合物)에 미치는 영향(影響) (Effects of Ionizing Radiation on Development of Wound Periderm, Solanine Content, and the Formation of Carbonyl Compounds in Potato Tubers)

  • 이미순;김홍열;정지봉
    • 한국식품과학회지
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    • 제5권1호
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    • pp.65-69
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    • 1973
  • 여러가지 선량(線量)의 방사선조사(放射線照射)가 감자 박편(薄片)$(1\;cm{\times}2\;mm)$ 의 치유조직(治癒組織) 형성에 미치는 효과를 무균 상태하에서 조사(調査)하였다. 세포분열은 선량(線量)이 증가함에 따라 점차 억제되었고 16 krad 처리에서는 완전히 억제되었다. Solanine 함량은 선량(線量)에 따라 유의적(有意的)인 차이를 나타내지 않았다. 방사선조사(放射線照射)에 의하여 감자 괴경(塊莖) 내에 유기(誘起)된 carbonyl 화합물로부터 생성된 2,4-dinitrophenylhydrazone 침전물을 gas chromatograph 로 분리한 결과 formaldehyde 및 acetone 은 고선량(高線量)에서만 증가하는 경향을 보였다.

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Preparation of Interface-Assembled Carbonyl Reductase and Its Application in the Synthesis of S-Licarbazepine in Toluene/Tris-HCl Buffer Biphasic System

  • Ou, Zhimin;Xu, Jiahui;Du, Lihua;Tang, Lan;Niu, Yangping;Cui, Jian
    • Journal of Microbiology and Biotechnology
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    • 제28권4호
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    • pp.613-621
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    • 2018
  • In this study, interface-assembled carbonyl reductase (IACR) was prepared and used in the synthesis of S-licarbazepine in a toluene/Tris-HCl biphasic system. The carbonyl reductase (CR) was conjugated with polystyrene to form a surfactant-like structure at the interface of the toluene/Tris-HCl biphasic system. The interface-assembled efficiency of IACR reached 83% when the CR (180 U/mg) and polystyrene concentration were $8{\times}10^2g/ml$ and $3.75{\times}10^3g/ml$, respectively. The conversion reached 95.6% and the enantiometric excess of S-licarbazepine was 98.6% when $3.97{\times}10^6nmol/l$ oxcarbazepine was converted by IACR using 6% ethanol as a co-substrate in toluene/Tris-HCl (12.5:10) at $30^{\circ}C$ and $43{\times}g$ for 6 h. IACR could be reused efficiently five times.

Characterization of Lignin Structure in Chemithermomechanical Pulp Predicting Photo-Yellowing Level by Pyrolysis-Gas Chromatography with Tetrabuthylammonium Hydroxide

  • Ona, Toshihiro;Yoshioka, Aki;Kojima, Yasuo;Seino, Teruyuki;Mizumoto, Miho;Nozaki, Hideo;Ishida, Yasuyuki;Ohtani, Hajime
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.173-176
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    • 2006
  • Pyrolysis-gas chromatography (Py-GC) in the presence of organic alkali of tetrabutylammonium hydroxide (TBAH) was applied to characterize the polyphenol fragments with a carbonyl group causing different magnitude of photo-yellowing in chemithermomechanical pulp (CTMP) papers. Two different origin of CTMP papers prepared from different individuals of Eucalyptus globulus trees showing high and low yellowing after photo-irradiation was compared before photo-irradiation. As a result, 7 peaks assigned to a series of phenol compounds with a carbonyl group, derived mainly from lignin, gave significant amount of phenol compounds with a carbonyl group for the paper sample of latent high yellowing, i.e., butoxy-and syringaldehyde, butoxy-and syringylacetone, butoxy-acetoguaiacone, butoxy-acetosyringone, butoxy-acetoethylsyringone, 3-methoxy-4-butoxy butyl ester, and 3,5-dimethoxy-4-butoxy butyl ester, using Py-GC/mass spectrometry (MS). The Py-GC method combined with TBAH successfully characterized polyphenol fragments with a carbonyl group causing differ high photo-yellowing in CTMP papers using a microgram order of samples.

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단체급식소 및 가정에서 식용유의 사용실태와 산패도에 관한 조사 연구 (A Study on Rancidity of Edible Soybean Oil by Cooking Frequency in Mass Meal Services and Homes)

  • 서은숙;한소현;문범수
    • 한국식품위생안전성학회지
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    • 제9권4호
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    • pp.213-220
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    • 1994
  • Customary usage of oil at homes and rancidity of edible soybean oil by cooking frequency at homes and mass meal services were investigated. 80% of house wives bought the cooking oil by 1.8ι unit container and 70% of them read either the manufactured date or explanatory note for use. 85% of house wives kept oil in the storage case under sink or in the pantry chest, and 80% of oils were used once or twice and 20% used three times for cooking. Acid value(AV), iodine value(IV), peroxide value(POV), carbonyl value(CoV) and thiobarbituric acid value(TBAV) of fresh soybean oil were lower than standard level. In the rancidity by cooking frequency, the acid value, peroxide value, carbonyl value and thiobarbituric acid value increased significantly when oil was used once and iodine value decreased significantly when used once and twice at both mass meal services and homes. The level of the acid value, iodine value, carbonyl value and thiobarbituric acid value of oil used at mass meal services did not show significant difference from those of oil used at homes. But, the peroxide value of oil used thrice at mass meal services was significantly higher than those of homes.

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대기 중 Carbonyl 성분들의 검량 분석 기술에 대한 연구: 액상 대비 기체상 표준시료의 오차발생 특성 연구 (A Study of Calibration Bias in the Analysis of Airborne Carbonyl Compounds between Gaseous and Liquid-phase Standards by High Performance Liquid Chromatography (HPLC))

  • 이민희;김기현
    • 한국대기환경학회지
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    • 제28권1호
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    • pp.52-58
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    • 2012
  • In this study, the effect of standard phase difference in calibration of carbonyl compounds (CC) was evaluated by using their standards prepared in both gaseous and liquid phase. For this analysis, standards in both phases were prepared for 6 different CCs (formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA) and valeraldehyde (VA)) at similar concentration levels. Their gaseous standard was calibrated after derivatization with three types of DNPH cartridge, and their calibration results were compared against liquid-phase standards. Although there was a strong compatibility between 2 phases for CCs with lower molecular weights (e.g., formaldehyde and acetaldehyde), it was not the case for the heavier CCs. The results of our analysis indicate that the analytical bias of the heavier CCs can be significantly large (by more than a few tens of %). As a result, underestimation of hevier CCs can be significant, if their gaseous samples are quantified by liquid phase standard.

아미드-아미드 및 아미드-용매 상호작용에 관한 Raman 분광학적인 연구 (Raman Spectroscopic Investigations of the Amide-Amide and Amide-Solvent Interactions)

  • 유정아;최영상
    • 대한화학회지
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    • 제27권6호
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    • pp.399-404
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    • 1983
  • 아미드와 아미드-용매계의 C=O stretching band에 해당하는 Raman 스펙트럼으로 부터 카르보닐기와 질소에 치환된 알킬기가 수소결합에 미치는 영향을 조사하였다. Formamide 계에서는 상호작용의 세기가 아미드-아미드>아미드-물>아미드-알코올 순으로 감소했으며, acetamide와 propionamide 계에서는 아미드-물>아미드-아미드>아미드-알코올 순으로 감소하였다. 카르보닐기에 알킬기가 치환되면 카르보닐기의 proton acceptor의 세기가 증가되며, 질소에 알킬기가 치환되면 proton donorcity가 감소함을 보이는데 이는 이론적인 계산 결과와도 일치한다.

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자동산화에 의한 Phytofluene으로부터 산화개열산물의 생성 (Formation of Oxidative Cleavage from Phytofluene by Autoxidation)

  • 김선재
    • 한국식품영양과학회지
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    • 제29권4호
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    • pp.568-574
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    • 2000
  • Phytofluene를 dichloromethane에 용해하고 dry ice 상에서 ozonolysis를 행하였다. Ozonolysis에 의해 생성된 화합물은 silica gel chromatography를 행 하여 분획하고, photodiode array detector를 이용하여 ODS-HPLC로 분석하였다. Phytofluene을 5% Tween 40 수용액에 용해하고 37$^{\circ}C$, 24시간 자동산화시킨 결과, 다수의 carbonyl 및 acidic 화합물의 생성되었다. Phytofluene의 자동산화로부터 생성된 carbonyl 화 합물의 대부분은 ozonolysis에 얻어진 산화개열산물이 나타내는 HPLC상의 거동과 분광학적 특성이 서로 잘 일치하였다. 또한 phytofluene의 자동산화에 의해 생성된 중앙개열 acidic 화합물은 생성활성을 나타내는 4,5-didehydrogeranyl geranyl acid 표준품과 동일한 분광학 적 특성을 나타냈다. 이러한 결과는 in vitro 상의 산화적 조건하에서 phytofluene의 자동산 화에 의해 eccentric cleavage가 생성됨을 알 수 있었다.

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신축공동주택의 실내공기 중 카보닐화합물의 방출특성에 관한 연구 (A Study on Emission Characteristics of Carbonyl Compounds for Indoor Air in New Apartment)

  • 류정민;조태진;장성기;손부순
    • 한국환경과학회지
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    • 제19권7호
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    • pp.807-818
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    • 2010
  • The study is about variations in Carbonyl compounds concentration within apartment buildings according to pre-residence and residence. We consecutively investigated indoor air pollutants in 120 households in 6 cities at pre-residence and residence. Carbonyl compounds were collected using the 2,4-DNPH cartridge and were analyzed using HPLC. The carbonyls concentration of indoor air in the new apartments before occupation measured formadlehyde($76.0\;{\mu}g/m^3$), acetone($85.9\;{\mu}g/m^3$), acetaldehyde($13.8\;{\mu}g/m^3$). The carbonyls concentration of indoor air in the new apartments after occupation measured formadlehyde($233.1\;{\mu}g/m^3$), acetone($128.9\;{\mu}g/m^3$), acetaldehyde($29.8\;{\mu}g/m^3$), respectively. As a result, the mean concentration of carbonyl compounds within the pre-occupancy stage was lower than those of residence.