• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.1
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• pp.120-136
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• 1999

A newly synthesized polyhydroxy aromatic compound(LG 106w) has good skin lightening effect. Inclusion complexation of LG 106w with $\beta$-cyclodextrin and its hydroxypropyl and dimethyl derivatives was studied by the solubility method, scanning electron microscopy and differential thermal analysis. A relationship between host and guest was clearly reflected in the magnitude of the stability constant(DM-$\beta$> HP-$\beta$>$\beta$ -cyclodextrin). Formulation problems, which resulted from its very low solubility in aqueous solution, were resolved by the inclusion formation. LG 106W from inclusions is much more water-soluble than pure one. The improvement of pH and temperature stability correlated with the increased solubility was also observed. Inclusion complex of LG 106w had similar activity to pure LG 106w on the inhibition of melanin synthesis in B-16 melanoma cell but showed lower irritation on cultured cell test in vitro. According to the results, cyclodextrins might be one of the reliable candidates for improving the availability of LG 106w.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.805-809
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• 2012

To evaluate the effects of liquid pig manure (LPM) on green manure crop yields, plant height and biomass of green manure crops were investigated in single and companion cropping. Green manure crops used for this experiment were Hordeum vulgare L. (green barley) and Vicia villosa roth (hairy vetch). Field experiment was designed with LPM 1.65 (LPM of $1.65ton\;10a^{-1}$ + single and companion green crops), LPM 3.3 (LPM of $3.3ton\;10a^{-1}$ + single and companion green crops) and LPM 6.6 (LPM of 6.6$6.6ton\;10a^{-1}$ + single and companion green crops). In single cropping, plant height were high in LPM 3.3. In companion cropping, plant height were high in LPM 6.6. Thus, we found that application of LPM is general enough to reduce use of chemical fertilizer. Also, optimum application level in single cropping would be LPM 3.3 and in companion cropping would be higher than LPM 3.3.

• Journal of Food Hygiene and Safety
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• v.5 no.1
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• pp.21-26
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• 1990

The effect of gamma irradiation on microbiological quality of fresh mushrooms (Agricus bisporus) were investigated. Gamma irradiation was found to be effective in lowering microbial counts initially and throughout storage. Decreases in microbial counts were strongly correlated with doses initially and during storage. Microbial counts of 2 to 3 kGy irradiated mushrooms remained significantly lower than unirradiated control mushrooms for a period of up to 2 to 3 weeks when stored at $9\;{\pm}\;1^{\circ}C\;and\;80\;{\pm}\;7%$ RH. Therefore, qualitative and quantitative changes in mushroom microflora by irradiation contributed to overall increases in shelf life of fresh mushrooms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.609-614
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• 1997

C-MH(Choline salt of maleic hydrazide, 39％) has been applied on peanut(Arachis hypogaea L.) plant in 1994∼1995 on three different times of 24 days after flowering (DAF), 28 DAF and 31 DAF and on three different levels of 0.2, 0.1. 0.067％, respectively. Main stem length was noticeably retarded by 38∼44％ compared to that of non-treatment. Branch numbers were not changed by C-MH treatments. Ratio of flowering inhibition was 38％ in 0.2％ concentration and 22％ in 0.067％ at 28 days after flowering treatment compared to that of control. Ratio of pure seed was slightly enhanced by 3％ in 28 DAF treatments. Yield productivity was increased by 7％ in 0.1％, at 28 DAF treatment compared to that of non-treatment (3.2MT /ha).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.247-253
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• 1982

This experiment was conducted to find out the optimum date for Combine harvesting of barley in the double cropping paddy field. By the consideration of moisture contents of grain, grain loss, rate of unhulled grain, and discoloring of external plant parts, the optimum date for harvesting was observed to be about 41 days after heading under natural condition. On the other hand, when desiccant was applied on the 34 days after heading, it could be shortened natural harvesting time for 3 days without any yield loss and grain qualities, too.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.35-42
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• 1979

Experiments were conducted to find out the labor saving efficiency and optimum seeding rate and fertilizer level when newly invented Barley Rotor Caster was used in wheat sowing on paddy field. It decreased the labor for sowing by 66~77% compared with conventional sowing method. And the optimum. seeding rate was considered to be approximately 20$\ell$Q per 10a in standard fertilizer level and optimum fertilizer level to be 18-12-12kg/10a, $N-P_2O_5-K_2O$ respectively.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.498-504
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• 2006

The etch rates of photoresist (PR) and the etch selectivity of $SiO_2$ to PR in a high density $CHF_3$ plasma were investigated at different ion-incident angles and bias voltages. A Faraday cage was employed for the accurate control of ion-incident angles. The ion energy was controlled by changing bias voltages. The etch rate of $SiO_2$ continuously decreased with ion-incident angles but the etch rate of PR remained constant up to the middle angle region and decreased afterwards. The etch rates of $SiO_2$ normalized to those at $0^{\circ}$ incident angle changed with the ion-incident angle following a cosine(${\theta}$) curve. On the other hand, the normalized etch rates of the PR changed showing a drastic over-cosine shape in the middle angle region. The etch selectivity of $SiO_2$ to PR decreased with an increase in the ion-incident angle because the etch yields of PR were enhanced by physical sputtering in the middle angle region compared to the case of $SiO_2$ etching. The etch selectivity of $SiO_2$ to PR decreased with an increase in the bias voltage at nearly all ion-incident angles.

• Journal of the Korean Electrochemical Society
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• v.12 no.2
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• pp.173-180
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• 2009

In order to develop a novel polymer electrolyte membrane for direct methanol fuel cell (DMFC), styrene monomer was graft-polymerized into poly(tetrafluoroethylene perfluoropropyl vinyl ether) (PFA) film followed by a sulfonation reaction. The graft polymerization was prepared by the $\Upsilon$-ray radiation-grafting method. Subsequently, sulfonation of the radiation-grafted film was carried out in a chlorosulfonic acid/1,2-dichloroethane (2 v/v%) solution. The chemical, physical, electrochemical and morphological properties of the radiation-grafted membranes (PFA-g-PSSA) were characterized by fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The water uptake, ionic conductivity, and methanol permeability of the PFA-g-PSSA membrane were also measured. The cell performances of MEA prepared with the PFA-g-PSSA membranes were evaluated and the cell resistances were measured by an impedance analyzer. The MEA using PFA-g-PSSA membranes showed superior performance for DMFCs in comparison with the commercial Nafion 112 membrane.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.55-61
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• 1984

A Korean local maize line, MET, which has multi-ears and tillers has been proved as a potential source for silage production. However, no fundamental genetic nature for the line has been investigated. Therefore, this study was done to find genetic information on the multi-earing and -tillering habits of MET line. MET line and a hybrid. (Mo 17 ${\times}$ B68), with monoculm and single ear per plant were used for production of F$_1$(F$\_$1-12/ and F$\_$1-21/), F$\_$2-12/, F$\_$2-21/, BC$\_$1-12/ and BC$\_$1-21/ generations. From the comparison of reciprocal crosses, it was found that the tillering and earing habits of the MET line are controlled by cytoplasmic factors. The tiller and ear numbers, and barren ears were all characters associated with the MET cytoplasm. The cytoplasmic effect of MET on tiller and ear numb en was not evident in F$_1$ generation, probably because of suppressing effect of heterosis on appearance of tillers or ears. Genetic parameters for the gene action for both tiller and ear number also indicated a lack of mono- or digenic-chromosomal gene effects. The heritability (broad) was very low for both characters. Therefore, it is strongly concluded that the tillering and earing characters of MET line are due to cytoplasmic reasons.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.406-406
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• 2010

일반적으로, 나노스케일의 MOS 소자에서는 게이트 절연체 두께가 감소함에 따라 tunneling effect의 증가로 인해 PID (plasma induced damage)로 인한 소자 특성 저하 현상을 감소하는 추세로 알려져 있다. 하지만 요즘 많이 사용되고 있는 high-k 게이트 절연체의 경우에는 오히려 더 많은 charge들이 trapping 되면서 PID가 오히려 더 심각해지는 현상이 나타나고 있다. 이러한 high-k 게이트 식각 시 현재는 주로 Hf-based wet etch나 dry etch가 사용되고 있지만 gate edge 영역에서 high-k 게이트 절연체의 undercut 현상이나 PID에 의한 소자특성 저하가 보고되고 있다. 본 연구에서는 이에 차세대 MOS 소자의 gate stack 구조중 issue화 되고 있는 metal gate 층과 gate dielectric 층의 식각공정에 각각 중성빔 식각과 중성빔 원자층 식각을 적용하여 전기적 손상 없이 원자레벨의 정확한 식각 조절을 해줄 수 있는 새로운 two step 식각 공정에 대한 연구를 진행하였다. 먼저 TiN metal gate 층의 식각을 위해 HBr과 $Cl_2$ 혼합가스를 사용한 중성빔 식각기술을 적용하여 100 eV 이하의 에너지 조건에서 하부층인 $HfO_2$와 거의 무한대의 식각 선택비를 얻었다. 하지만 100 eV 조건에서는 낮은 에너지에 의한 빔 스케터링으로 실제 패턴 식각시 etch foot이 발생되는 현상이 관찰되었으며, 이를 해결하기 위하여 먼저 높은 에너지로 식각을 진행하고 $HfO_2$와의 계면 근처에서 100 eV로 식각을 해주는 two step 방법을 사용하였다. 그 결과 anistropic 하고 하부층에 etch stop된 식각 형상을 관찰할 수 있었다. 다음으로 3.5nm의 매우 얇은 $HfO_2$ gate dielectric 층의 정확한 식각 깊이 조절을 위해 $BCl_3$와 Ar 가스를 이용한 중성빔 원자층 식각기술을 적용하여 $1.2\;{\AA}$/cycle의 단일막 식각 조건을 확립하고 약 30 cycle 공정시 3.5nm 두께의 $HfO_2$ 층이 완벽히 제거됨을 관찰할 수 있었다. 뿐만 아니라, vertical 한 식각 형상 및 향상된 표면 roughness를 transmission electron microscope(TEM)과 atomic force microscope (AFM)으로 관찰할 수 있었다. 이러한 중성빔 식각과 중성빔 원자층 식각기술이 결합된 새로운 gate recess 공정을 실제 MOSFET 소자에 적용하여 기존 식각 방법으로 제작된 소자 결과를 비교해 본 결과 gate leakage current가 약 one order 정도 개선되었음을 확인할 수 있었다.