• 한국환경보건학회지
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• 제42권3호
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• pp.160-168
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• 2016

Objectives: Materials coming into contact with food may result in the migration of chemical substances into the food. To protect consumers from exposure, Regulation (EU) No. 10/2011 specifies the use of standard migration tests. Polyethylene terephthalate (PET), widely used for food packaging materials, has drawn the attention of researchers because unwanted migration of PET into food might occur when consumers reuse packaging material. The aim of this study was to predict and develop a migration model for two components, acetaldehyde and butyraldehyde in PET, into food simulants under conditions of changing pH and solvents, such as those observed in fermented foods like kimchi or sauerkraut. Methods: Using a migration model based on Fick's second law of diffusion in one dimension, the migration of acetaldehyde and butyraldehyde from PET into a simulant of fermented food at $20^{\circ}C$ over 10 days was evaluated. The simulant for fermented food was modelled as 10% ethanol for three days, followed by 3% acetic acid for seven days. Results: The migration of acetaldehyde into the 10% ethanol was 0.36 times that of a simulated fermented food system, while that of butyraldehyde was 1.34 times greater. These results may have been influenced by the chemical interactions among the migrants, polymers and simulants, as well as by the solubilities of the migrants in polymers and simulants. Conclusion: Because food simulants have a limited capacity to mimic real food systems under the current migration model, an appropriate simulant and migration test should be considered in the case of increasing acidity. Furthermore, since the accuracy of the worst-case estimation of migration predicted by the current model is severely limited under changing food conditions, food simulants and their interactions should be further investigated with respect to conservative migration modelling.

• 한국대기환경학회지
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• 제22권5호
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• pp.679-692
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• 2006

The carbonyl compounds in the atmosphere belong to one of the regulatory pollutants for the malodor control designated by the Korean Ministry of Environment(KMOE). In the present study, the emission concentration levels of carbonyl compounds were measured along with a number of criteria odor pollutants from a total of 47 individual companies(June 2004 to January 2005). The results of our study showed that a number of carbonyl compounds(such as formaldehyde, acetaldehyde, acetone, and butyraldehyde) maintained significantly high mean concentrations of 298 to 372 ppb. In contrast, other carbonyl compounds were low enough with the mean valves of 0.54 to 19.1 ppb. It was found that except for such industries as metal production or leather processing, their emissions were generally quite significant. If the measured values were evaluated in terms of malodor intensity, butyraldehyde appeared to be the most significant contributor to the malodor release. According to the measurements made in strong source areas, it can be concluded that several carbonyl compounds(acetaldehyde, propionaldehyde, butyraldehyde, isovaleraldehyde, and valeraldehyde) are useful enough to diagnose malodor release from those source areas. It should also be addressed that a number of carbonyl compounds added newly as the result of malodor control legislation were not sensitive enough to diagnose malodor release from such sources.

• 한국연초학회지
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• 제11권2호
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• pp.203-210
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• 1989

Leucine and isoleucine were reacted with glucose in a propylene glycol solution and volatile compounds produced from these reaction were analysed by gas chromatography and mass spectrometry. A total of 24 compounds were identified in the leucine reaction volatiles and the major components were 2-isopropyl-5-methyl-2-hexenal, methylbutyraldehyde PGA, butyraldehyde PGA, 5-methylfur-fural, isopropylmethylhexenal PGA and 2-acetylpyrrole. From the isoleucing reaction volatiles, 20 compounds were identified and the major components were methylbutyraldehyde PGA, butyraldehyde PGA and 2-acetylpyrrole. The amino acids chosen for this study were considered as giving fruity and cocoa aroma when heated with glucose.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2208-2212
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• 2009

Oxidation of cycloalkenes with $O_2$ promoted by heterogeneous bis(acetylacetonato) cobalt (II) complex catalyst which can be recycled has been performed under mild conditions. It was found that $\beta$-ionone, cyclohexene, 1-methylcyclohexene, and $\alpha$-ionone were efficiently oxidized with $O_2$ in the presence of Co (II) complex and butyraldehyde at $55\;{^{\circ}C}$. A simple treatment of the resulting products led to epoxides as predominant products and a small amounts of allylic oxides, the chemoselectivity for the former being 82.1 - 90.8% with a 70.6 - 98.6% substrate conversion. On the other hand, oxidation of 1-phenylcyclohexene, 1-cyclohex-1-enylethan-1-one, $\alpha$-pinene, and $\beta$-pinene gave allylic oxides as major products.

• 한국환경보건학회지
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• 제23권4호
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• pp.39-44
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• 1997

Propionaldehyde, n-Butyraldehyde, n-Valeraldehyde 수용액에 주파수 200 kHz, 출력 6.0 W/cm$^2$의 초음파조사후 그 분해반응에 관해 고찰했다. Aldehyde류는 초음파 조사에 의해 빠르게 분해되었고, 분해형태는 유사1차 반응을 나타내었다. 이들의 분해 속도는 Propionaldehyde

• 한국환경보건학회지
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• 제39권5호
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• pp.418-425
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• 2013

Objective: This study was carried out for the purpose of identifying major substances contributing to the production of odor and evaluating the characteristic of odors. Methods: Complex odor and 17 odorous compounds were measured at 18 waste transfer stations located in Seoul. Results: The dilution ratio value of complex odor ranged from 4 to 30 times in the boundary layer of 18 waste transfer stations. At 6 measurement points among the 18 waste transfer stations, the dilution ratio values exceeded standards (15 times). When the results were evaluated in terms of their contribution to the formation of malodor, the patterns indicated that the highest concentration values in the residential waste disposal process were of i-valeraldehyde and acetaldehyde, while butyraldehyde and acetaldehyde accounted for a large proportion of odorous compounds from the waste recycling process. Conclusions: It was found that butyraldehyde and acetaldehyde were the primary compounds released from the food waste disposal process. Overall, aldehyde compounds were the greatest contributor to detectable odor intensity emitted at the waste transfer stations.

• 대한환경공학회지
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• 제31권12호
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• pp.1161-1168
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• 2009

본 연구는 시화공단 단지에서 발생하는 주요 악취물질의 특성을 조사하였다. TVOC의 블록 별 분포를 보면 기계블록인 장소 D의 농도가 74 ppb로 가장 높았다. 화학블록인 장소 A가 그 다음으로 높은 50 ppb의 농도를 보였으며, 복합블록과 금속블록, 공원 등은 30 ppb 내외의 유사한 농도 수준을 보였고, 복합블록인 장소 F에서 평균 TVOC가 18 ppb로 가장 낮게 측정되었다. 평균 TVOC 농도는 35 ppb로 나타났다. 아세트알데히드, 뷰티르알데히드 등을 비롯한 알데히드류와 황화수소의 농도가 시화공단 지역의 악취물질 중에서 높게 나타났다. 대표적으로 악취 강도가 높은 물질인 아세트알데히드, 뷰티르알데히드, 황화수소를 중심으로 블록 별 악취강도를 비교해 본 결과 장소 A, B(화학블록)와 장소 D, I(기계블록), 장소 H(금속블록)에서 세 물질의 악취강도가 모두 1을 넘었다. 아세트알데히드의 경우 악취강도가 2 내외로 비교적 높게 나타나는 경우가 많았다. 황화수소의 경우 상관계수의 값이(r) 0.91로 악취강도와 황화수소 성분 사이에 매우 높은 양의 상관성이 있는 것으로 확인되었다. 뷰티르알데히드도 상관계수가 0.82로 역시 높은 양의 상관성을 보였다. 악취물질 농도로는 가장 큰 값을 보였던 아세트알데히드는 상관계수가 0.62로 악취강도와 어느 정도의 상관성이 있는 것으로 나타났다.

• 방사성폐기물학회지
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• 제6권3호
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• pp.163-170
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• 2008

30 % TBP/NDD-2 M $HNO_3$ (0.005 M $K_2Cr_2O_7$ 함유) 계에 의해 산화 추출된 Np의 유기상을 대상으로 n-butyraldehyde (NBA)에 의한 Np의 환원 역추출을 고찰하였다. Np의 역추출은 NBA의 농도 증가에 따라, 역추출 수용상 내 질산농도 감소에 따라, 그리고 반응 온도 감소에 따라 증가하였으며, 이때 겉보기 환원 역추출 속도식은 $-d[Np]_{Org.}/dt$ =1,524 exp(-2,906/T) $[NBA]^{0.91}\;[H^+]^{-0.92}[Np]_{Org.}$. 이었다. 1.04M NBA 및 2M $HNO_3$에서 Np 및 U의 역추출률은 각각 70.1 % 및 7.1 % 이며 이때 분리계수(($=D_U/D_{Np}$)는 30.4 정도로, TBP-$HNO_3$ 계에 의해 공추출된 Np과 U은 NBA에 의해 효과적으로 상호 분리할 수 있음을 알 수 있었다.

• 대한화학회지
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• 제15권3호
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• pp.117-120
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• 1971

Possibility of two phase reduction of carbonyl compounds to the corresponding alcohols was studied. Thus the 0.5 M ether solutions of the representative carbonyl compounds were treated with alkaline stabilized sodium borohydride aqueous solution at room temperature. Butyraldehyde was reduced rapidly within one hr., whereas other aldehydes tested; heptaldehyde, benzaldehyde, and 1-naphthaldehyde were reduced in 6-12 hr. 2-Heptanone was reduced much slowly; 87% in 48 hr., however, acetophenone was reduced moderately; 92% in 12 hr. and cycloalkanones were reduced rapidly (cyclohexanone in 0.5 hr., and cyclopentanone in 3-6 hr.).

• 대한화학회지
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• 제7권1호
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• pp.85-90
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• 1963

The Knoevenagel reaction of fluorinated carbonyl compounds, 1,1,1-trifluoro-propanone-2-heptafluoro-butyraldehyde, 1,3-dichloro-1,1,3,3-tetrafluoro-acetone, tetradecafluoro-heptanone-4 and 2,2,2-trifluoro-acetophenone yielded fluorinated ${\beta},{\beta}$-dialkyl-${\beta}$-hydroxy acids. Dehydration of the acids do not give the olefinic acid in the case of the perfluorinated system and gave a lactone. From the consideration of electronic and steric effects a mechanismic path of the reaction via a carbanion intermediate was proposed for the reaction. Preparation of related derivatives are also described.