• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.241-242
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• 2002

최근 들어 지표면 오존농도의 증가에 기여하는 오존전구물질에 대한 관심이 증대되면서 오존전구물질에 대한 분석방법의 확립에 많은 노력을 기울이고 있는 실정이다. 지금까지는 비극성 column을 이용하여 저온 농축과정을 거쳐 분석을 수행하거나 극성 및 비극성 column을 병렬로 연결하여 환경대기 중의 오존전구물질을 측정한 연구사례가 대부분인 것으로 보고되고 있으나 이러한 저온농축과정 및 다수의 column을 사용할 경우 소요되는 장비 및 시간에 대한 비경제적인 측면을 고려하지 않을 수 없다. (중략)

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.13-19
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• 1999

Insecticidal potentials of polar and non-polar tractions obtained from 84 medicinal plants were screened against five major agricultural insects. Based on the primary and secondary screening results, non-polar fraction of Atractylodes koreana Kitam. rhizomes was selected to isolate and identify an active compound effective to diamondback moth (Plutella xylostella L.) larvae. Counter-current distribution separation on the non-polar fraction and TLC and spectroscopic analyses (GC-MS and $^{1}H$- and $^{13}C$-NMR) revealed that molecular formula of the active compound was $C_{15}H_{22}O$ known as a sesquiterpenoid 4,11-selinadien-3-one (${\alpha}$-cyperone). However, ${\alpha}$-cyperone was not detected in the non-polar fractions that showed high insecticidal potential against the diamondback moth. Although ${\alpha}$-cyperone has been first identified from Cyperus rotundus, the compound did not occur in C. rotundus cultivated in Korea.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.948-954
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• 2005

In this study, we investigated antimicrobial and cytotoxicity effects to each fraction extracted from Solanum lyratum (SL), which were extracted methanol (SLM) and then the extract was fractionated into five different types : hexane (SLMH), ethyl ether (SLMEE), ethylacetate (SLMEA), butanol (SLMB) and aqueous (SLMA). The antimicrobial activity was analyzed by the paper disc method. Among the various solvent fractions, SLMEA showed the strongest antimicrobial activies. The cytotoxicity of SL fractions on HeLa, MCF-7, HT-29 and HepG2 cells was evaluated by MTT assay. Among various partition layers, SLMEE showed the strongest cytotoxic effects to all cancer cell lines. We also observed that quinone reductase (QR) was induced by all fraction layers of SL to HepG2 cells. Since the QR-induced effects of SLMEE on HepG2 cells at $160{\mu}g/ml$ concentration showed 2.1 when compared with a control value of 1.0, inducer of QR for cancer protection may be contained in this fraction.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.743-748
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• 2013

The purposes of this study are to prepare Hanji fiber-filter sheets using replacement liquid in water-swollen fiber with non-polar solvent such as ethanol, methanol and pentane. The experiments were studied on the selection of optimal non-polar solvent and the optimal drying method for wetted fiber and then were to know physicochemical characteristics of prepared Hanji fiber-filter sheet. The Ethanol as liquid changer in water-swollen fiber was excellent solvent and the optimal drying method for them was freeze drying served with vacuum pump. The bulk density and porosity of prepared fiber sheet from freeze dryer were 0.11-0.13 g/mL, half of natural dried fiber sheet, and 90%, respectively. The results of SEM observation for the fiber sheet prepared with natural drying or heating drying were shown very close structure of fiber wall in dry state. However, the freeze drying sheet were shown the open structure. So, the head loss of freeze drying sheet was very lower than natural drying and heating drying sheets. From the results of BTEX removal experiments, the sheets dried at water wetted condition was shown more higher efficiency than the fiber sheets dried at solvent wetted condition.

• Analytical Science and Technology
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• v.13 no.4
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• pp.511-519
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• 2000

Water in the supercritical state ($T{\geq}374^{\circ}C$, $p{\geq}221$ atm) is a good solvent for nonorganic pollutants, but it is extremely corrosive. Subcritical Water Extraction (SWE) is a very fast and an efficient method to extract nonpolar environmental pollutants adsorbed on the sediments and soils. Many nonpolar organic compounds are sufficiently soluble to be extracted to the water under subcritical conditions. Complete extraction of PCBs from the sediments and soils takes only a few minutes by applying SWE with the subcritical water at 50 atm and at $260^{\circ}C$.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.37-38
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• 1998

물질을 분리하기 위해서는 두 물질간의 현저한 물리적 성질의 차가 있어야 한다. 일반적으로 막분리법을 이용하여 기체분리를 수행하느 경우에는 확산계수와 용해도 차이에 의한 투과선택도를 얻게 된다. 막분리를 위한 기체간의 물리적 성질로는 기체의 크기차이, 고분자에 대한 기체용해도 차이 등이 있다.(생략)

• KSBB Journal
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• v.15 no.4
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• pp.408-410
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• 2000

The supercritical fluid extraction(SFE) technique was applied for the isolation and purification of nonpolar physiologically acitve mateials from Agaricus blazei fruiting bodies. the qualitative analysis of extract was accomplished by gas chromatography-mass spectrometer(GC-MS) and extract was determined as linoleic acid(cis-9 cis-12-octadecadienoic acid) In order to obtain the optimum operating conditions of supercritical fluid extraction process the various temperatures and pressures were applied for process operation. From the comparison of exraction efficiencies $50^{\circ}C and 200 kg_f/cm^2$ were determined as optimum conditions.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.42-48
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• 1994

The toxic compounds of sorghum stem extracts were isolated by different organic solvents and pH, and characterized and quantified in terms of their inhibition of seed germination and seedling growth in Echinochloa colona(L.) Link and radish(Raphanus sativus L.). Sequential partitioning of stem extract with various organic solvents with increasing polarity showed that all fractions of hexane, ethyl ether, methylene chloride, ethyl acetate, and the aqueous remainder inhibited germination and seedling growth in E. colona. Of the five fractions, the ethyl ether fraction had the greatest inhibitory effect on E. colona. Further separation of the ethyl ether fraction at different pH(pH 2-11) showed that phytotoxic compounds were acidic. The result indicates that the phytotoxin present in the stem extract may be nonpolar and acidic.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.121-127
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• 1988

For selective purification of protein in Pleurotus cornucopiae (Per.) Rolland, affinity chromatography was performed by benzoyl-AH-Sepharose 4B gel synthesized using AH-Sepharose 4B with starting materials. Ligand capacity of benzoyl group was 9.3 micromole per milliliter of gel. Total apparent molecular weight of affinity protein was 255KD, which were protein complex of 29.5, 31.5 34.0, 71.0 and 89.0KD, respectively. The contents of nonpolar, polar, positively charged, and negatively charged amino acid were 45.68%, 26.93%, 11.81% and 15.58%, respectively. The nonpolar protein was selectively purified by hydrophobic ligand of benzoyl group of gel.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.25-32
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• 2011

We have studied on the slicing and polishing processes of R-plane sapphire wafers for the substrates of UHB nonpolar a-plane GaN LED. The fabrication conditions of the R-plane and c-plane wafers were influenced by the large anisotropic properties (mechanical properties) of the sapphire. The slicing process was more affected by the anisotropic properties of R-plane than the polishing process. When the slicing direction was $45^{\circ}$ to the a-flat, the slicing time was shorter and the quality of as-slicing wafers was better than the slicing direction of normal to the a-flat. The MRR(Material removal rate) of mechanical polishing processes such as lapping and DMP(Diamond mechanical polishing) did not show significant differences between the R-plane and c-plane. The MRR of the c-plane was about two times higher than that of R-planes at the CMP(Chemical mechanical polishing) process due to the formation of hydrolysis reaction layers on the surface of the c-plane.