• Title/Summary/Keyword: Carbonyl (CO)

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Contribution of Primary and Secondary Sources to the Atmospheric Concentrations of Carbonayl Compounds in Seoul (서울지역에서 대기 중 카르보닐 화합물 농도에 대한 1,2차 발생원의 기여율 산정)

  • 여현구
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.4
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    • pp.317-326
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    • 2000
  • Carbonyl compounds have been measured in downtown Seoul for September 1998 using 2-series impinger method. Average concentration (ppbv) of carbonyl compounds were 12.66$\pm$5.77 HCHO, 12.05$\pm$4.86 CH3CHO and 7.92$\pm$2.63 CH3CHCH3 These compounds were the most abundant carbonyl,. They showed maximum concentration during the daytime when photochemical activity was very strong minimum concentration were usually showed during the night and early morning. Comparison of diurnal variation of carbonyl compounds with the concentration of O3, NMHC, CO and meteorological data indicated that primary and secondary sources contributed the observed carbonyl compounds. Photochemical Formation Rate(PFR) of carbonyl compounds dur-ing the sampling periods were 61% HCHO, 85% CH3CHO, 85% CH3CHO, 71% CH3COCH3.

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Catalytic Isomerization of Allyic Alcohols to Carbonyl Compounds with Rh(ClO$_4$)(CO)(PPh$_3)_2$ and [Rh(CO)(PPh$_3)_3$]ClO$_4$

  • Chin Chong Shik;Park Jeonghan;Kim Choongil
    • Bulletin of the Korean Chemical Society
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    • v.10 no.1
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    • pp.102-103
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    • 1989
  • Four coordinated rhodium(Ⅰ) complexes, Rh($ClO_4$)(CO)$(PPh_3)_2$ and [$Rh(CO)(PPh_3)_3$]$ClO_4$(2) catalyze the iosmerization of allylic alcohols to the corresponding carbonyl compounds at room temperature under nitrogen. The isomerization is faster with 2 than with 1, which is understood in terms of relative ease of the last step of the catalytic cycle, the reductive elimination of enol. Relative rates of the isomerization with 1 and 2 for different allylic alcohols are also explained by the relative ease of the enol elimination step in part. The first step of the catalytic cycle, the complex formation of the allylic alcohol through the ${\pi}-system$ of the olefinic group of the allylic alcohol and the following step, formation of hydridoallyl complex also seem to affect the overall rate of the isomerization.

Carbonylation of (Dichloromethyl)benzene Catalyzed by Cobalt Carbonyl and Iron Carbonyl under Phase Transfer Catalysis

  • Sang Chul Shiim;Chil Hoon Doh;Dong Yub Lee;Jae Goo Shim;Young Zoo Youn;Woo Hyung Park;Li Hong Jiang;Ju Hee Kim
    • Bulletin of the Korean Chemical Society
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    • v.14 no.5
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    • pp.618-620
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    • 1993
  • Treatment of (dichloromethyl)benzenes with CO (1 atm) in the presence of catalytic amount of $Co_2(CO)_8,\;Fe(CO)_5$ and BTEAC under two phase systems with NaOH(_{aq}) and $PhCH_3$ containing small amount of alcohol for 20 hours at 80$^{\circ}$C gives phenylacetic acids in moderate yields.

Reactions, Hydrogenation and Isomerization of Unsaturated Esters with a Rhodium(I)-Perchlorato Complex

  • Jeong Hyun Mok;Chin Chong Shik
    • Bulletin of the Korean Chemical Society
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    • v.7 no.6
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    • pp.468-471
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    • 1986
  • The isolated products from the reactions of $Rh(ClO_4)(CO)(PPh_3)_2$ (1) with CH_2$ = $CHCO_2C_2H_5$ (2) and trans-$CH_3CH$ = $CHCO_2C_2H_5$ (3) contain 80∼ 90% of $[Rh(CH_2 = CHCO_2C_2H_5)(CO)(PPh_3)_2]ClO_4$ (4) and [Rh(trans-$CH_3CH = CHCO_2C_2H_5(CO)(PPh_3)_2]ClO_4$ (5), respectively where 2 and 3 seem to be coordinated through the carbonyl oxygen. It has been found that complex 1 catalyzes the isomerization of $CH_2 = CH(CH_2)_8CO_2C_2H_5$ (6) to $CH_3(CH_2)_nCH = CH(CH_2)_{7-n}CO_2C_2H_5$ (n = 0∼7) under nitrogen at 25$^{\circ}C$. The isomerization of 6 is slower than that of $CH_2 = CH(CH_2)_9CH_3$ to $CH_3(CH_2)_nCH$ = $CH(CH_2)_{8-n}CH_3$ (n = 0∼8), which is understood in terms of the interactions between the carbonyl oxygen of 6 and the catalyst. It has been also observed that complex 1 catalyzes the hydrogenation of 2, 3, 6, trans-$C_6H_5CH = CHCO_2C_2H_5$ (7), $CH_3(CH_2)_7CH = CH(CH_2)_7CO_2C_2H_5$ (8) and $CH_2 = CH(CH_2)_9CH_3$ (9), and the isomerization (double bond migration) of 6 and 9 under hydrogen at 25$^{\circ}C$. The interactions between the carbonyl oxygen of the unsaturated esters and the catalyst affect the hydrogenation in such a way that the hydrogenation of the unsaturated esters becomes slower than that of simple olefins.

Inhibitory Effects of Eel (Anguilla japonica) Extracted Carnosine on Protein Glycation (뱀장어(Anguilla japonica)로부터 추출된 Carnosine의 단백질당화 억제효과)

  • Song, Ho-Su;Lee, Keun-Tai;Park, Seong-Min;Kang, Ok-Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.2
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    • pp.104-108
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    • 2009
  • Glycation and oxidation induce formation of carbonyl (CO) groups in proteins, which can be used to develop an index of cellular aging. Methyl glyoxal (MG) and hypochlorite anions are deleterious products of oxygen free-radical reaction. The effects of eel carnosine on protein modification mediated by MG and hypochlorite were studied. MG and hypochlorite induced formation of carbonyl groups with high molecular weight and cross-linked forms of ovalbumin. The presence of eel carnosine effectively inhibited these modifications in a concentration-dependent manner. Imidazole ring in eel carnosine might have a primary role in inhibition of protein glycation. Our data suggests that the eel carnosine may be useful as a "natural" anti-glycating agents.

Ionic Hydrogenation of Carbonyl Groups With Molybdenum and Tungsten Complexes (몰리브덴과 텅스텐 착물을 이용한 카르보닐기의 이온성 수소화 반응)

  • Song Jeong-Sup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.715-720
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    • 2006
  • Metalhydrides such as $Cp(CO)_{2}(L)MH$ (L = t-butylisocyanide and 2,6-dimethylphenylisocyanide M = Mo and W) have been synthesized and used for ionic hydrogenation of the carbonyl groups in the presence of triflic acid. When these complexes have also used as catalyst precursors for hydrogenation of 3-pentanone under mild conditions ($23^{\circ}C,\;<4.1\;atm H_{2}$). The turnover rates were very slow, with the fastest initial rate of about 2 turnovers per 1 day for the [$Cp(CO)_{2}(ArNC)Mo][BA_{r}^{F}_{4}$] system.

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Kinetic Studies on the Reaction of the Heterobimetallic Anion, $(OC)_5CrMn(CO)_5{^-}M^+\;(M^+=Na^+,\;PPN^+)$ with Allyl Bromide

  • Park, Yong K.;Kim, Gyu S.;Song, Gwan O.
    • Bulletin of the Korean Chemical Society
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    • v.16 no.4
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    • pp.310-315
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    • 1995
  • The heterobimetallic anion, (OC)5CrMn(CO)5-M+ (M+=Na+, PPN+), which has a donor-acceptor metal-metal bond1, was reacted with allyl bromide to yield BrCr(CO)5- and Mn(CO)5(CH2CHCH2). The reaction mechanism has been proposed in terms of the consecutive reaction pathway in which Cr(CO)5(THF) is an important intermediate leading to the corresponding product. Counterion effect on this reaction was also evaluated and the results were compared with those of the corresponding reaction of the mononuclear carbonyl anion, Mn(CO)5-.

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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    • v.28 no.4
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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.

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

  • 서은숙;한소현;문범수
    • Journal of Food Hygiene and Safety
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    • v.9 no.4
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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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