• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.546-550
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• 2014

Relative reactivity of various carbonyl and acid derivatives in MPV-type (Meerwein-Ponndorf-Verley) reduction with an DIBAL(F) model has been studied via DFT and MP2 methods. Free energies of initial adduct formation (-Gadd) of DIBAL(F) model and carbonyls are in the order of amide < ester < aldehyde < ketone < acid chloride; in the alan-amide adduct, the developed positive charge at carbonyl carbon is expected to be stabilized by amide resonance, but in the acid chloride adduct it is destabilized by inductive effect of chloride. However the TS barrier energies (${\Delta}G_{TS}$) for the MPV-type hydride reduction of the carbonyl adducts are in the order of aldehyde < ketone < acid chloride << ester < amide; presumably decreasing order of electrophilicity of carbonyl carbon at adducts, which is well correlated with experimental data. It is noted that the relative reactivity of carbonyl derivatives in MPV-type reduction with DIBAL(X) is not governed by the alan-adduct formation energies, but follows the order of electrophilicity of carbonyl carbon of transition states.

• Journal of Nutrition and Health
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• 제18권3호
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• pp.189-193
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• 1985

Qualitative and quantitative analysis for carbonyl compounds contained in the five kinds of filtrated myulchichuts have been made using HPLC. Carbonyl compounds were separated by converting them into 2,4-dinitrophenylhydrazine derivatives which, in turn extracting with hexane. The extract was dehydrated, filtered and examined on HPLC with $C_{18}column$. The quantitative determination of carbonyl species was achieved using standard calibration technique. Highly reproduceable results were obtained by this methods and the amounts of 2,4-dinitrophenylhydrazine derivatives were highly correlative to peak heights. As the results, we find that the seven kinds of carbonyl compounds are contained in each of myulchichuts examined in this study. Five of which are identified as pyruvic acid, formaldehyde, acetaldehyde, acetone and butanone. But the amounts of carbonyl compounds vary widely with the kinds of the filtrated myulchichuts.

• 한국대기환경학회지
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• 제12권2호
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• pp.199-209
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• 1996

The purpose of this study is to evaluate analytical method for the measurement of carbonyl compounds and to apply method to the measurement of indoor and outdoor concentrations of these compounds at public facilities. For sampling, 2.4-dinitrophenylhydrazine (DNPH) coated DNPH-Silica cartridges were uwed in this study. DNPH reacts with carbonyl compounds and forms carbonyl hydrazone, The carbonyl hydarzone was eluted from the cartridge with acetonitrile and analyzed by reverse-phase HPLC with UV detection. Possible interference caused by ozone during sampling was eliminated by using KI trap commected in series with the DNPH-Silica cartridge. A number of experimental studies were undertaken to evaluate and validate the analytical method, including collection efficiency, recovery, repeatability, lower limits of detection, and effect of ozone. Indoor and outdoor measurements of carbonyl compounds were simultaneously carried out at 14 public facilities located in Taegu city and Kyungsan city from June to July, 1995. Except for one or two sites, the indoor concentrations were found to be higher than the outdoor concentrations for carbonyl compounds. And the concentrations of carbonyl compounds measured in the morning and afternoon were showed higher than the concentrations measured in the evening.

• 대한화학회지
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• 제24권5호
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• pp.347-355
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• 1980

${\alpha}$- 및 ${\beta}$-염화나프탈렌카르보닐의 가메탄올 분해반응속도를 메탄올-아세톤, 메탄올-아세토니트릴 혼합용매 속에서 측정하였다. 각 혼합용매마다 공통적으로 ${\alpha}$-염화나프탈렌카르보닐이 ${\beta}$-염화나프탈렌카르보닐보다 반응속도 상수가 크게 관측되었다. 이것은 Dewar수 Nr과 Streitwieser의 ${\sigma}^+$값과도 일치하였다. 카르보닐탄소가 천이상태에서 $sp^3$로 바뀌어 인접수소에 의한 입체장애가 없어지는 것을 알 수 있었다.

• 한국대기환경학회지
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• 제16권4호
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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.

• 한국연초학회지
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• 제25권2호
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• pp.137-143
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• 2003

Among the most popular means of mainstream smoke collection for specific analysis are solvent traps. Determination of the carbonyl compounds as their 2,4-dinitrophenylhydrazones(DNPHs) by HPLC offers increased sensitivity and reproducibility in the analysis of mainstream cigarette smoke. In this work, the mainstream smoke of a reference cigarette(lR4F) was collected in four kinds of gas washing bottles and their effects on the analysis of carbonyl compounds were investigated. The results show that the porosity of fritted glass filter in gas washing bottles exerted profound effect on the composition of the carbonyl compounds in mainstream smoke.

• 한국연초학회지
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• 제26권2호
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• pp.159-167
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• 2004

This work has been conducted to select appropriate filter materials for removing carbonyl compounds in mainstream tobacco smoke. To investigate of the usability of this filter materials, two types of bead ion exchangers were synthesized and their adsorption characteristics for carbonyl compounds were investigated. Sulfonic acid group-containing cation exchanger and ammonium group-containing anion exchanger were synthesized by the suspension polymerization of glycidylmethacrylate(GMA) and divinylbenzene(DVB) followed by the subsequent functionalization, respectively. The removal efficiency of carbonyl compounds by these two ion exchangers increased in the presence of moisture. However, the amount of carbonyl compounds adsorbed on the anion exchanger was larger than that on the cation exchanger under two levels of water contents tested. This phenomenon seems to arise from the electron delocalization in carbonyl group of the anion exchangers. There was not any significant relationship between the amount of carbonyl compounds adsorbed on ion exchangers and the length of adsorption column. From the large ion exchange capacity and rapid ion exchange reaction rate of the anion exchanger, it is suggested that the anion exchanger may be a good filter material for removing carbonyl compounds in the mainstream tobacco smoke.

• 한국연초학회지
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• 제31권1호
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• pp.45-50
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• 2009

In this study, a simple gradient RRLC method for rapid determination of carbonyl compounds of cigarette smoke was developed. Within 10 min, 8 carbonyl compounds have been separated and identified on ZORBAX Eclipse XDB-C18 column ($4.6{\times}50\;mm$, $1.8\;{\mu}m$) with gradient elution using water and acetonitrile as a mobile phase. RRLC was used for the quantification of carbonyl compounds in mainstream smoke of 3R4F reference cigarette, and evaluated those efficiencies in the recovery, repeatability and reproducibility. The correlation coefficients ($r^2$) for calibration curves of carbonyl compounds were over 0.9998. The developed RRLC method was successfully applied to the analysis of smoke samples and the recoveries of carbonyl compounds were in the range of 97.5~102.1% with RSD<3.1%.

• 한국식품영양과학회지
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• 제14권1호
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• pp.61-66
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• 1985

취반(炊飯) 중의 가열반응(加熱反應)에 의하여 일어나는 주요 쌀성분(成分)의 화학적(化學的) 변화(變化) 및 휘발성(揮發性) carbonyl 화합물(化合物)의 생성(生成) 양상(樣相)을 쌀밥 및 누른밥으로 나누어 살펴 본 결과는 다음과 같다. 취반에 의한 가열반응(加熱反應) 결과 총(總)아미노산 및 유리아미노산 중의 몇 가지 아미노산이 감소되었으며 그 감소율은 유리아미노산에서 더 높았고, 환원당 역시 감소되었다. 또한 유지획분에 있어서 구성지방산 조성(組成)의 경미한 변화, 요오드가(價)의 감소, 지방산(價)의 증가 등을 주목할 수 있었다. 한편 휘발성향기성분에서 carbonyl 화합물을 분리하여 GC, GC-MS, TLC 방법에 따라 잠정적으로 8개의 carbonyls을 확인하였고(4개는 완전히 동정(同定)함) 이들의 조성을 비교하였다. 전반적으로 쌀밥보다는 누른밥에서 이와 같은 화학적 변화가 심하였고 쌀밥과 누른밥의 주요 휘발성 carbonyl 화합물 조성도 상이(相異)하였다. 그리고 이러한 취반과정에서는 변화와 관련되는 가열반응(加熱反應) mechanism을 아울러 검토하였다.

• 한국대기환경학회지
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• 제24권2호
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• pp.206-219
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• 2008

The purpose of this study is to evaluate concentrations of carbonyl compounds during summer season in Seoul metropolitan area. The air samples were collected at 7 sites in this area from June 2001 to June 2003. The carbonyl compounds were analyzed by DNPH/HPLC method. The analytical method applied in this study showed good repeatability, linearity, and sensitivity. The most abundant carbonyl was formaldehyde (average 4.48 ppb), and followed by acetone, acetaldehyde, methyl ethyl ketone, butyraldehyde, propionaldehyde and benzaldehyde, respectively. Concentrations of carbonyl compounds in June were higher than those in August. There was not only higher solar radiation but also higher ozone concentration in June than in August. As a result o photochemical reactions, carbonyl compounds from both primary and secondary sources are likely to contribute to the formation of ozone. The contributions to photochemical ozone creation of two carbonyl compounds such as formaldehyde and acetaldehyde were estimated to be about 70%. Ratios of formaldehyde to acetaldehyde in this study ranged from 1.13 to 4.26, which are generally equivalent levels to those of other urban areas in domestic and foreign countries.