• 대한화학회지
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• 제29권4호
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• pp.414-418
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• 1985

3차 알릴 알코올을 산화하여 ${\alpha},\{\beta}$-불포화카르보닐 화합물을 얻은 일반적인 방법을 검토하였다. 비교적 간단한 화합물의 경우 우수한 수득율로 작용기가 이동된 카르보닐 화합물을 얻을 수 있었다. 따라서 이 반응은 유용한 합성 수단이 될 수 있다.

• 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.

• 대한화학회지
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• 제46권2호
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• pp.139-144
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• 2002

니켈 착물을 촉매로 사용한 1,1´-Bis(dimethylsilyl)ferrocene [1]과 carbonyl 화합물 -benzaldehyde, 4-cyanobenzaldehyde, trimethylacetaldehyde, acetophenone과 benzophenone-은 3-oxa-2,5-disilacyclo-1,1′-ferrocene을 생성하였다. 이와 대비되게 동일한 반응조건에서 화합물 [1]과 isobutyraldehyde의 반응에는 1,1′-bis(dimethylsilyl)ferrocene의 Si-H 결합에 2개의 aldehyde ligand가 이중 삽입된 생성물이 형성되었다.

• Applied Biological Chemistry
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• 제40권5호
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• pp.455-458
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• 1997

Crude oils in the rhizoma of fresh and dried Gastrodia elata were obtained by a simultaneous steam distillation and extraction(SDE) method using n-pentane/diethyl ether (1 : 1) as solvent, and their volatile constituents were analyzed by gas chromatography-mass spectrometry(GC/MS) A total of 39 volatile flavor constituents (11 acids, 13 alcohols,6 hydrocarbons,7 carbonyls,2 esters) and 25 constituents (6 alcohols, 13 acids, 4 hydrocarbons, 1 carbonyl, ester) were identified in the fresh and dried Gastrodia elate respectively. The major volatile components of the fresh and dried sample were hexadecanoic acid(66.78%, 50.72%), 9-hexadecenoic acid(8.07%, 9.58%), heptadecanoic acid(2.01%, 0.13%), pentadecanoic acid(6.41%, 4.94%), p-cresol(1.43%,0.52%) and cyclododecene(1.83%, 6.00%).

• 공업화학
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• 제3권3호
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• pp.407-411
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• 1992

본 연구는 상이동 촉매를 이용하여 group 6 금속 카르보닐 착물($M(CO)_6$ [M=Cr, Mo, W])의 CO 리간드를 두자리 전자쌍 주게 리간드(L)인 2, 2'-bipyridine와 2, 2'-biquinoline에 의해서 치환된 $M(CO)_4(L)_2$를 생성할 때 반응 시간, 촉매의 첨가량, 리간드의 종류가 생성물의 수율에 미치는 영향을 관찰하였다.

• Bulletin of the Korean Chemical Society
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• 제18권12호
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• pp.1264-1268
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• 1997

The poly(methylsilene) (1) was modified with the group 4 metallocene Cp2MCl2/Red-Al (M = Ti, Zr, Hf) combination catalyst and with the group 6 metal carbonyl M(CO)6 (M = Cr, Mo, W) catalyst, producing the highly cross-linked isoluble polymer and the lowly cross-linked soluble polymer, respectively. An interrelationship between molecular weight and percent ceramic residue yield with metal within the respective group was not found. The polymers modified with the group 4 metallocene combination catalysts have higher molecular weight and lower percent ceramic residue yield than the polymers modified with the group 6 metal carbonyl catalysts do. The catalytic activity of group 4 metallocene combinations appears to be higher at ∼100 ℃, but to be lower at very high temperature than those of group 6 metal carbonyls. The pyrolysis of the modified 1 yielded SiC ceramic.

• Bulletin of the Korean Chemical Society
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• 제19권12호
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• pp.1310-1314
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• 1998

The oligo(methylsilene) (1) was treated with the group 4 metallocene Cp2MCl2/Red-Al (M = Ti, Zr, Hf) combination catalysts and with the group 6 metal carbonyl M(CO)6 (M = Cr, W) catalysts, producing the modified, cross-linked polymers. The average molecular weights and percent ceramic residue yields of modified polymers increase as the catalyst goes down from Ti to Hf and similarly as the catalyst goes down from Cr to W. An interrelationship between average molecular weights and percent ceramic residue yield is found within the respective group of catalysts, but is not observed as the catalyst goes down from Ti to W. The polymers modified with the group 4 metallocene combination catalysts have higher molecular weights and similar percent ceramic residue yields as compared to the polymers modified with the group 6 metal carbonyl catalysts. The catalytic activities of group 4 metallocene combinations appear to be higher -100 ℃, but to be lower at very high temperature than those of group 6 metal carbonyls.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.812-824
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• 2020

Objective: The aim of this work was to assess the effect of fermented blueberry (FB; 2%, 4%, and 6%) on the oxidative stability and volatile molecule profiles of emulsion-type sausage stored at 4℃ for 28 days. Methods: The antioxidant activity of FB was determined through radical-scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. Four formulations of sausage treatments with different FB levels (0%, 2%, 4%, 6%) were prepared, then peroxide value (POVs), thiobarbituric acid-reactive substances (TBARS) values, protein carbonyls and thiol groups were measured. The aroma profiles of sausages for each treatment was also determined. Results: The half maximal inhibitory concentration indicated that FB had greater scavenging ability than ascorbic acid against DPPH and hydroxyl radicals. Sausages with FB significantly retarded increases in POVs and TBARS, as well as in the content of protein carbonyls during all storage days (p<0.05). Particularly, 4% and 6% FB-treated sausages had better oxidation inhibition effects. However, FB accelerated the reduction in thiol groups (p<0.05). Additionally, FB inhibits the excessive formation of aldehyde compounds; for example, hexanal, which may cause rancid flavors, decreased from 58.25% to 19.41%. FB also created 6 alcohols (i.e., 2-methyl-1-propanol, 3-methyl-1-butanol, and phenylethyl alcohol), 5 ester compounds (i.e., ethyl acetate, ethyl lactate, and ethyl hexanoate) and 3-hydroxy-2-butanone in the sausages that contribute to sausage flavors. The principal component analysis showed that the aroma profiles of sausages with and without FB are easily identified. Conclusion: The addition of FB could significantly reduce the lipid and protein oxidation and improve oxidative stability for storage. Also, adding FB could inhibit rancid flavors and contribute to sausage flavors.

• 한국식품영양학회지
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• 제13권5호
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• pp.453-459
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• 2000

본 연구에서는 식품차원의 연구분야 일환으로서 먼저 복분자의 일반성분, 유리당, 유리아미노산, 무기성분 및 향기성분 등을 보고하였다. 복분자의 총당은 17.3%, 환원당은 8.6%, 조단백질 10.6%, 조회분은 4.5%, 조지방은 3.1%, 조섬유는 3.9%이고, 유리당 함량은 sucrose 1.52%, fructose 3.98%, glucose 1.24%이고, 유기산 함량은 citric acid 10.2%, oxalic acid 6.29%로 가장 많이 함유하고 있었고, 그 다음은 magic acid 1.94%였다. 총 아미노산은 7,841.5mg%이고, 필수아미노산 함량은 2,989.8mg%로 나타났다. 복분자에 가장 많이 함유되어 있는 아미노산은 aspartic acid 1,260.3%이었고. 그 다음은 glu-tamic acid 1,054.3% 순으로 함유하고 있었다. 무기성분은 K가 387mg으로 가장 많이 함유되어 있었고, 향기성분은 복분자에서 총 52종의 성분이 확인되었는데 확인된 성분들은 관능기별로 분류하면 amyl alcohol를 포함한 alcohol류 11종, valeric acid를 포함한 acid류 13종, hexanal를 포함한 carbonyl류 20종, 2-hep-tanone를 포함한 hydrocarbon류 5종 그리고 methyl palmitate를 포함한 ester류가 3종이었다. 관능기별로 확인된 성분들의 총 peak area%를 살펴보면 alcohol 류 11.56%, acid류 38.87%, hydrocarbon류 2.89%, ester류 0.80%, 총 70.32%가 확인되었다. Alcohol류에서 linalool가 3.78%, acid류에서는 caproic acid류가 14.40%, car-bonyl류에서 2-hydroxy-4-methoxyace-tophenone이 2.99%, hydrocarbon류에서는 aromaden-dren가 1.59% 그리고 ester류에서는 methyl palmi-tate가 7.43%으로 가장 많이 함유되어 있었다.

• 한국식품영양학회지
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• 제17권3호
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• pp.260-265
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• 2004

솔잎(Pinus densiflora S.)의 휘발성 성분을 추출시간과 온도를 달리하면서 headspace(purge & trap)-GC/MS로 분석하여 총61개의 휘발성 성분을 확인하였다. 확인된 성분을 관능기별로 분류하여 보면 hydrocarbons 35종, alcohols 16종, carbonyls 4종, ethers 3종, esters 2종, acid 1종으로 나타났다. 솔잎에서 확인된 주요 휘발성 성분으로는 $\alpha$-pinene(1.5～15.7%), $\beta$-pinene(0.4～5.4%), $\beta$-myrcene(13.2～15.6%), $\beta$-phellandrene (12.0～16.0%), cis-3-hexenol(4.0～18.3%), $\beta$-caryophyllene (3.6～6.8%) 등이 확인되었다. 또한 headspace(purge & trap)법에 의해 솔잎의 휘발성 성분 분석시 최적 조건을 검토하기 위해 실온에서 2시간과 20시간동안 추출한 것과 6$0^{\circ}C$에서 2시간과 20시간동안 각각 추출했을 때 실온에서 2시간 추출시 가장 많은 56개의 성분이 확인되었고, 실온에서 2시간 추출시 가장 적은 45개의 성분이 확인되었다. 시험조건에 따른 휘발성분 분석에서 비점이 낮은monoterpenes화합물들은 추출시 초기에 주로 추출되어 지고 alcohols류와 비점이 높은 sesquiterpenes 화합물들은 추출시간을 길게 했을 때 더 많은 성분이 추출된다는 것을 알 수 있었다. 4가지 추출조건을 종합해 볼 때 고비점 휘발성 성분 분석에는 6$0^{\circ}C$에서 20시간 추출이 가장 양호하나, 전반적으로 실온에서 20시간 추출이 가장 적합한 조건인 것으로 나타났다.