• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1424-1426
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• 2010

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3559-3560
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• 2011

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.623-625
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• 1997

This study was carried out to investigate the effect of storage period on flavor components of Korean kiwifruits (Actinidia deliciosa Planch.) stored at $20^{\circ}C$. The major volatile components of Korean kiwifruits analyzed by GC and GC-MS were pentanal, methyl butanoate, ethyl pentanoate, heptanone, (E)-2-hexenal, ethyl hexanoate, 1-hexanol, cyclohexanol, butyl hexanoate, linalool oxide, linalool, butyl heptanoate, methyl benzoate, ethyl benzoate. Among them, (E)-2-hexenal was the major component in premature fruit but on further ripening ethyl butanoate began to dominate the component profile.

• YAKHAK HOEJI
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• v.19 no.2
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• pp.96-100
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• 1975

2-Ethoxy-4-acetamidobenzoate (III) was synthesized by ethylation of N-formyl compound obtained with formylation of methyl 4-aminosalicylate and 2-ethoxy-4-acetamidobenzamide (VIII) was synthesized by ethylation of 4-acetamidosalicylamide (VII) formed by reacting methyl 4-acetamido-2-acetoxy benzoate with concentrated ammonia water under pressure. 2-Ethoxy-4-acetamido benzamide (VIII) was also synthesized by acetylation of 2-ethoxy-4-aminobenzamide (VI) obtained by pressure eraction of methyl 2-ethoxy-4-formylamido-benzoate (I) with concentrated ammonia water.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.11 no.1
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• pp.13-20
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• 1985

The decreased preservative effect by tale and $TiO_2$ for emulsions obtained with polyoxyethylene surfactant was studied by various analytical methods and biological test. The preservative effect of methyl p-hydroxybenzoate was decreased by the addition of talc and $TiO_2$ and this result was attributed to the adsorption of methyl p-hydroxybenzoate on them. Talc exhibited more decreased preservative effect than that of $TiO_2$. The amount of the adsorption of methyl p-phydroxybenzoate by talc at $20^{\circ}C$ could be represented by the following equation; $a=11.511C^{0.747}$.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.140-145
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• 1999

Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.80-86
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• 2002

The activities against Frankliniella occidentalis adults collected at rose greenhouse of 40 commerical insecticides were investigated. Among them 9 insecticides showed over 80% mortality to the adults; chlorfenapyr, chlorpyrifos- methyl, emamectin benzoate, fenthion, fipronil, phenthoate, spinosad, chlorpyrifos+diflubenzuron and furathiocarb+diflubenzuron. Susceptibility of field populations collected from greenhouse rose at 5 locations in 2001 was evaluated against the 9 insecticides selected. There was considerable difference in susceptibility depending on the treated insecticides and the regions from which the populations were collected. Goyang and Gimhae populations showed lower $LC_{50}$(ppm) values then Imsil, Jincheon and Gaangjin populations to all the tested insecticides. The adults of all field populations showed lower $LC_{50}$ values less than 1 ppm to emamectin benzoate, fipronil and spinosad. From these results, we could recommend 5 insecticides, such as emamectin benzoate, fipronil, spinosad, chlorpyrifos+diflubenzuron and furathiocarb+diflubenzuron as effective ones to control the Frankliniella occidentalis field populations.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.73-76
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• 2005

The acaricidal activities of 12 commercial constituents derived from Eugenia caryophyllata leaf oils against Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae adults were examined using an impregnated fabric disk application and compared with that of the commercial benzyl benzoate as synthetic acaricide. On the basis of $LD_{50}$ values, the most toxic compound was methyl eugenol ($4.13\;{\mu}g/cm^2$), followed by methyl isoeugenol ($4.19\;{\mu}g/cm^2$), isoeugenol ($4.29\;{\mu}g/cm^2$), eugenol ($4.94\;{\mu}g/cm^2$), and acetyl eugenol ($13.91\;{\mu}g/cm^2$) against D. farinae. In the case of D. pteronyssinus, isoeugenol ($2.93\;{\mu}g/cm^2$) was the most toxic, followed by methyl isoeugenol ($3.28\;{\mu}g/cm^2$), methyl eugenol ($3.87\;{\mu}g/cm^2$), eugenol ($3.92\;{\mu}g/cm^2$), and acetyl eugenol ($7.21\;{\mu}g/cm^2$). These results suggest that D. pteronyssinus may be controlled more effectively by the application of eugenol congeners than D. farinae. In comparison with synthetic acaricides, the acaricidal activities of eugenol, isoeugenol, methyl eugenol, and methyl isoeugenol were about 1.9-2.2 times more toxic than benzyl benzoate. Furthermore, the most toxic constituent against T. putrescentiae was exhibited on eugenol ($10.11\;{\mu}g/cm^2$), followed by methyl eugenol ($38.67\;{\mu}g/cm^2$) and acetyl eugenol ($70.09\;{\mu}g/cm^2$), but no activity was observed for isoeugenol and methyl isoeugenol. The results suggested that eugenol congeners may be useful as a new source for selective control of house dust mites and stored food mites.

• Natural Product Sciences
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• v.27 no.3
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• pp.169-171
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• 2021

A new phenolic compound and three known flavonoids isolated from the MeOH extracts of Lespedeza tomentosa. Based on spectral data, the isolated compounds were identified as methyl 4,5-dihydroxy-3-methoxy-2-(3-methylbut-2-en-1-yl)benzoate (1), 1-methoxylespeflorin G₁₁ (2), farrerol (3) and 1-methoxylespeflorin I₂ (4). Methyl 4,5-dihydroxy-3-methoxy-2-(3-methylbut-2-en-1-yl)benzoate (1) is newly isolated from plant source.

• Journal of Photoscience
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• v.12 no.1
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• pp.41-46
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• 2005

We synthesized chiral choleseric liquid crystalline monomer p-phenylene bis-(p-3-acryloxy-2(S)-methylpropoxy)benzoate (1) and achiral nematic liquid crystalline monomer, p-phenylene p-acryloxy-6-hexyloxy-p-octyloxybenzoate (2) for the construction of cholesteric polymer network with a pitch gradient. In this research we attempted to synthesize cholesteric polymer film which have a wide reflection bandwidth in the region of visible wavelength with the synthesized chiral cholesteric monomer 1 and nematic monomer 2 under various photopoly merization conditions. We succeeded to construct cholesteric polymer film network with a pitch gradient covering more than 200 nm bandwidth in the visible wavelength by diffusion controlled photostructuring method.