• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.127-131
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• 2002

Migration of di-(ethylhexyl)phthalate (DEHF) from PVC food packaging materials detected plasticizer into food simulanting solvents(4% Acetic acid, 8% Ethanol, 50% Ethanol, 95% Ethanol, Heptane) were studied. For executing this study ,2 PVC food packaging materials detected DEHP were used. Analysis was by GC-FID and GC-MSD(selected ion monitoring) for DEHP, and optimized for quantification of plasticizer. The recovery of DEHP into food simulanting solvents were min. 87.4${\pm}$ 3.6 ∼ max. 109.9 ${\pm}$ 10.7% respectively. Following exposure to food simulants 95% Ethanol for 24hours at 60$^{\circ}C$ the migration results of 1020.90 ${\pm}$ 10.15$\mu\textrm{g}$/g, 563.54 ${\pm}$ 5.60$\mu\textrm{g}$/dm$^2$and 73.51 ${\pm}$ 5.09$\mu\textrm{g}$/g 149.22 ${\pm}$ 10.34$\mu\textrm{g}$/dm$^2$were detected from the container for lunch and for stock fish respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.104-109
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• 1996

고추의 효능을 높이기 위한 방법의 하나로 향신성 분을 보유하면서 자기저자이 가능한 oleoresin을 추출하여 유화제로 수용성을 부여시킨 후, 이때의 유화안 정성과 고온에서 조리를 하였을 때 고추 oleoresin의 항산화 활성을 검토하였다. 100mesh로 분쇄한 고추에 증류수에 가하여 감압증류시켜 정유성분을 추출하고, 잔사에 에틸 알코올을 가하여 $25^{\circ}C에서$ 3시간 진탕 추출한 후 여과, 농축시켜 정유성분과 합하였다. 여기에 물과 유화제 (PGDR)를 첨가, 유화시켜 고추 oleoresin으로 하였다. $60^{\circ}C에서$ 24시간 방치했을때의 enulsion 생성율은 PGDR을 4% 첨가한 경우가 94.5%로 가장 높았고, 또한 100분간 원심분리(200$\times$g) 시킨 후에도 emulsion 잔존율은 80%정도로서 유화안전성이 가장 좋았다. 고추 oleoresin의 항산화 활성은 가열조리 온도 100$\times$의 경우 BHA의 효과 만큼은 미치지 못하나 상당한 항상화성을 나타내었고, 온도 $150^{\circ}C의$ 경우는 BHA 첨가와 마찬가지로 항산화성 효과를 인정하기 어려웠다.

• Journal of the Korean Chemical Society
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• v.22 no.3
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• pp.138-148
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• 1978

A discussion of the various theories of natural diamond formation is given. Experimental data from mass spectrometric analysis of included gases is related to theoretical data on the carbon-hydrogen-oxygen gas phase under geologic conditions.Possible temperature-pressure conditions for natural diamond formation are proposed.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.1-5
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• 1997

The volatile components of Lycium chinensis Miller were isolated by simultaneous steam distillation-extraction(SDE) method and analyzed by combined GC and GC-MS. Fifty-four volatile components, including 12 alcolhols 12 esters, 7 aldehydes, 6 acids, 5 ydrocarbons, 8 ketones, 1 furan and 3 pyrazines were confirmed in the fruit of Lycium chinensis Miller. The major components were hexadecanoic acid ethyl ester, 1-octadecanone, tetrapyrazine, 2-furancarboxaldehyde and ethyl linoleate.

• Economic and Environmental Geology
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• v.45 no.5
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• pp.589-597
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• 2012

Recently, an understanding of new sources of liquid hydrocarbons such as bioethanol is economically very important. Bioethanol is actually ethyl alcohol or also referred to as ethanol, identical to drinking alcohol by its composition. There are mainly two ways of producing ethanol, namely by synthesis of hydrocarbons and from biomass. Only the second approach deserves the terminology 'bioethanol'. The present dissertation is also designed with purpose of developing the energy-saving process for the separation of bioethanol. The world population is expected to grow past 8 billion by 2030 which are almost 60% in Asia Pacific. History has shown that energy use rises much faster than population expands. World wide demand for energy will increase significantly during the next 15 years driven by population growth and the transition of emerging markets into the global economy. In developing nations, a smaller increment in GDP per capita yields a higher increment in energy consumption compared to developed countries. In this study, we analised total 2,454 dissertations for the bioethanol during the 2001~2012 periods by the programs of 'web of science' and 'recently developped program by Korea Institute of Science Technology Information'.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.581-587
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• 2005

In order to obtain a highly purified p-dioxanone (PDX) as monomer of biodegradable polymer, suitable solvent must be selected. The selection was based on the solubility of impurities, and partial layer melt crystallization were carried out under the presence of solvent. The solubility of PDX in various solvents such as ethyl acetate, tetrahydrofuran, acetone, alcohols (methanol, ethanol, 1-propanol, 1-butanol and 1-pentanol) were measured over the temperature range of $-10{\sim}15^{\circ}C$. As solubility parameters, the mixing and dissolution enthalpy between the PDX and the solvents was studied based on empirical equations and the regular solution theory. The solubility and the temperature dependency of the solubility with the solvents of acetone, ethylacetate, and tetrahydrofuran of PDX were shown to have relatively high values compared to the alcohol type solvents. Also, in same alcohols, the smaller molecules and higher polarity gave higher solvency. In partial layer melt crystallization, small amount of ethylacetate selectively dissolved impurities and gave highly purified p-dioxanone, over 99.9% purity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.211-215
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• 1983

The changes of microflora during fermentation of low salted sardine were observed. The viable cell count in the low salt fermented sardine with $8\%\;or\;10\%$ salt showed lower than that of control ($20\%$ salt) during the fermentation period and it was considered that the microbial growth was controlled by adding ethanol, sorbitol and lactic acid. Among 48 strains isolated, 7 genus of bacteria and 1 genus of yeast were identified during the fermentation of sardine. The changes of microflora also occurred during fermentation depending on the salt levels in the product. Brevibacterium, Pseudomonas, Flavobacterium and Baciilus were detected at early stage of fermentation and they disappeared after 50 days fermentation from the product with $20\%$ salt and Halobacterium, Micrococcus, Pediococcus and Torulopsis were isolated, whereas Brevibacterium, Micrococcus and Pediococcus were isolated from the product with $8\%\;or\;10\%$ salt.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.1
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• pp.1-7
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• 2014

Nanofluids, suspending nano-particles of various materials, have a good heat transfer characteristics compared with pure base fluids. For the reason, nanofluids have been considered as one of the measure to improve energy efficiency, and studied to apply on a working fluid of a high performance heat exchanger. This study tested thermal conductivities of nanofluids applying diamond nano-powder on DI water, ethylene glycol, and ethyl alcohol. Nanofluids are fabricated by matrix synthetic method, and the volume percent of diamond nano-powder contained in the base fluid are 0.1, 0.3, 0.5, and 1vol%. As a result, thermal conductivities are enhanced with applying diamond nano-power. Especially, the conductivity is highly increased up to 23% at 1vol% nanofluid applying diamond nano-powder on DI water.

• Journal of Conservation Science
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• v.28 no.3
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• pp.229-233
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• 2012

This research was to evaluate conservational stability of cleaning treatment and color recovery by weak acid treatment on ivory. Before this experiment, had an ivory identification such as black light and schreger angle to find whether it is authentic or not. In wet cleaning treatment on ivory, used polar solvents such as distilled water, acetone, ethyl alcohol and acetic acid which usually used for cleaning ivory and bones. After cleaning took a experiment to evaluate conservational stability in surface observation, calculate weight and color difference. Following these results, these polar solvents were stable on the ivory samples. On the other hand, in weak acid treatment, used samples that were exposed by UV-A, UV-B, UV-C for 1 weeks, to restore its color from changed to original color. After treatment, found tiny cracks and exfoliation on the surface. Moreover, the color changed when it is treated by lemon juice, so, it is impossible to adapt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.243-249
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• 2001

This study was investigated to determine the antimicrobial effect of the ethanol extract of Quercus mongolica leaf on microbial growth. The ethanol extract at the concentration of $250\;\mu\textrm{g}/mL\;and\;500\;\mu\textrm{g}/mL$ inhibited the growth of gram positive and gram negative food-borne disease bacteria for 40 hours in tryptic soy broth, respectively. Antimicrobial activity of the ethanol extract from Quercus mongolica leaf was not affected by pH and heat treatment. The comparision between ethanol extract and commercially available preservatives on antimicrobial activity in food system was conducted. When the 0.1% ethanol extract of Quercus mongolica leaf was added to pine needle drink and carrot juice, antimicrobial activity was similar to those of containing 0.05% benzoic acid and 0.5% grapefruit seed extract. Also addition of 2~3% ethanol extract to the soybean paste inhibited the microbial growth up to 7 week, comparable to the inhibition of 2% ethanol. Thus, this results indicate that the ethanol extract of Quercus mongolica leaf may be useful as natural antimicrobial agents.