• Polymer(Korea)
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• v.27 no.5
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• pp.464-469
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• 2003

In this work, the fragrant oil release behavior of poly($\varepsilon$-caprolactone) (PCL) microcapsules containing SiO$_2$ was investigated. The SiO$_2$ was chemically treated in 10, 20, and 30 wt% hydrochloric acid and sodium hydroxide. The acid and base values were determined by Boehm's titration technique and $N_2$/77 K adsorption isotherm characteristics, the specific surface area and total pore volume were studied by BET. The PCL microcapsules containing SiO$_2$ and fragrant oil were prepared by oil-in-water (o/w) emulsion solvent evaporation method. The shape and surface of PCL microcapsules were observed using image analyzer and scanning electron microscope (SEM). The fragrant oil release behavior of PCL microcapsules was characterized using UV/vis. spectra. The average diameters of PCL microcapsules were decreased from 35 to 21 $\mu$m with increasing stirring rate. It was found that in the case of acidic treatment the fragrant oil adsorption capacity and release rate were increased due to the increase of specific surface area and acid value. In the case of basic treatment, the fragrant oil adsorption capacity and release rate were decreased due to the decrease of sp ecific surface area and the increase of acid-base interactions between SiO$_2$-NaOH and fragrant oil with increasing base value of SiO$_2$.

• Applied Chemistry for Engineering
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• v.35 no.3
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• pp.209-213
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• 2024

To improve the adhesion properties between the conductive paste and PET film, the PET film was chemically treated using acids and bases and physically treated through corona discharge. A paste using ethylcellulose, which is used in actual industrial manufacturing and silane-treated CNF, as a binder was manufactured and coated on PET film to compare the adhesive properties. The specimen coated with a paste containing silane-treated CNF as a binder on a corona discharge-treated PET film showed the highest level of adhesion, 5B. On the other hand, it was confirmed that when PET film was chemically treated with acid/base, there was no improvement in adhesive properties.

• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.756-760
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• 2005

In this study, the effect of $N_2$-plasma treatment on carbon blacks (CBs) was investigated by analyzing acid-base surface values and surface functional groups of CBs. The surface characteristics of the CBs were determined by fourier transformed-infrared (FT-IR) spectrometer, X-ray photoelectron spectroscopy (XPS), and Boehm's titration method. Electrochemical properties of the plasma-treated CBs-supported Pt (Pt/CBs) catalysts were analyzed by cyclic voltammetry (CV) experiments. From the results of FT-IR and acid-base values, $N_2$-plasma treatment at 300 W intensity on the CBs led to the formation of the free radical. The peak intensity was increased with increasing the treatment time due to the formation of new basic functional groups(such as C-N, C=N, $-NH_3{^+}$, -NH, and =NH) by the free radical. Accordingly, the basic values were increased by the basic functional groups. However, after a specific reaction time, $N_2$-plasma treatment could hardly influence change of surface functional groups of CBs, due to the disappearance of free radical. Consequently, it was found that optimal treatment time was 30 second for electro activity of Pt/CBs catalysts.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.66-66
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• 2018

국화과(Compositae) 다년생 초본인 산국속(Dendranthema)은 국내 약 13여종이 자생하는 것으로 알려져 있으며, 이 중 감국(D. indicum (L.) Des Moul.)과 산국(D. boreale (Makino) Ling ex Kitam.), 구절초(D. zawadskii var. latilobum (Maxim.) Kitam.)가 주로 차 또는 한약재 등의 원료로 이용되고 있다. 차로 이용되는 꽃은 산국이 감국에 비해 상대적으로 작아서 구분이 가능하지만 시중에는 건조된 형태로 가공 유통되므로 육안으로 구분이 쉽지 않고, 산국 유래 제품들은 국내에서 감국 또는 국화로 혼용해서 표기되어 유통되고 있어 그 기원을 명확히 정립할 필요가 있다. 이에 본 연구는 감국과 산국의 분자유전학적 판별을 위해 DNA 바코드 후보 유전자를 활용하여 염기서열분석으로 확보된 SNP 및 InDel 정보를 바탕으로 CAPS 마커를 개발하고자 수행되었다. 감국과 산국 모두 trnL-trnF intergenic spacer 구간에서 약 1kb의 PCR 산물이 확인되었고, 이들 염기서열에서 분석한 2 SNP 및 3 InDel을 대상으로 CAPS 마커 개발을 위한 제한효소 사이트를 탐색하였다. Gap을 포함한 774bp (감국/산국=A/G) 위치의 SNP에서 BstUI(GC^GC)처리로 CAPS 마커로 전환 가능함이 확인되었고, 이에 감국과 산국의 PCR 산물에 제한효소를 처리한 결과, 제한효소 인식 사이트가 존재하는 산국에서 두 개의 DNA 단편이 확인되었다. 위 결과는 다양한 형태로 가공 유통되는 감국과 산국의 판별을 위한 마커로 활용될 수 있으며, 본 연구에 활용된 기술은 추후 건강기능식품 개발을 위한 원료표준화 확립 연구에 유용할 것으로 판단된다.

• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.130-137
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• 2011

Pedicularis growing at Mt. Halla of Jeju Island is known as an endemic species of P. hallaisanensis Hurusawa. On the other hand, the plant is morphologically similar to P. amoena, P. spicata, and P. verticillata in gross morphology, so the taxonomic treatment of the taxon remains controversial. To clarify the taxonomic position of the plants, we examined external morphological characters and nuclear ribosomal DNA ITS sequences for P. hallaisanensis and its related species. The plants of Mt. Halla are clearly different from P. amoena and P. verticillata in the morphology of calyx lobes, the length of galea and lower lip, density of glandular hairs on plants, presences of the radical leaves after anthesis and molecular data. However, P. hallaisanensis is not clearly separated from P. spicata distributed in N. E. Asia on external morphological characters and DNA sequences of internal transcribed spacers. In this study, the morphological and molecular data suggested that P. hallaisanensis should be merged into the former species.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.87-94
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• 2013

To investigate the effects of functional MA films (FMA) masterbatched by zeolite powder treated with 1 N HCl, 0.5 N NaCl solution and anti-fogging agent (NA) compared with control on the freshness extension of 'Fuji' apples during storage at $15^{\circ}C$. Preference, weight loss, total ascorbic acid, sugar content, acidity, change of gas composition in package were measured. After 150 days of storage, the weight loss of control (L) apples was 1%, that of apple in FMA film (NA) was 1.5% after 150 days. Total ascorbic acid content of apples in control (L) after 150 days was 2.09 mg%, those of apple in FMA film (NA) was 2.72 mg%. The titratable acidity of apple in FMA film was higher than that in control, while soluble solids content of apples in FMA film was lower than that in control after 150 days. Ethylene gas adsorbability in control was 192.2 ppm and those in FMA film was 141.4 ppm after 150 days. Overall, apples in FMA film was better than that of control. It was verified that apples packed with LLDPE film (control) lasted about 130days, while those with FMA films lasted about 170 days. Also, FMA films treated with anti-fogging agent few different compare to nontreated film, but commerdity on the display in market was considered higher than that of non-treated anti-fogging agent.

• Korean Chemical Engineering Research
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• v.43 no.5
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• pp.632-636
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• 2005

In this work, the effect of chemical treatments on surface properties of SiC was investigated in thermal and mechanical interfacial behaviors of SiC/PMMA nanocomposites. The acid/base value, contact angles, and FT-IR analysis were performed for the study of surface characteristics of the SiC studied. The thermal stabilities of the SiC/PMMA nanocomposites were investigated by thermogravimetric analysis (TGA). Also the mechanical interfacial properties of the composites were studied in critical stress intensity factor ($K_{IC}$) and critical strain energy release rate ($G_{IC}$) measurements. As a result, the acidically treated SiC (A-SiC) had higher acid value than that of untreated SiC (V-SiC) or basically treated SiC (B-SiC). The acidic solution treatment led to an increase in surface free energy of the SiC, mainly due to the increase of its specific component. Thermal and mechanical interfacial properties of the SiC/PMMA nanocomposites, including initial decomposition temperature (IDT), $K_{IC}$, and $G_{IC}$ had been improved in the acidic treatment on SiC. This was due to the improvement in the interfacial bonding strength, resulting from the acid-base interfacial interactions between the fillers and polymeric matrix.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.103-110
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• 2006

T-RFLP analysis and clone sequencing analysis based on bacterial 16S rDNA were conducted to assess bacterial community structure and diversity in Zoysia japonica soil treated with liquid fertilizer containing amino acids(LFcAA) after spray with herbicide. The results of T-RFLP (terminal restriction fragment length poly-morphism) analysis using restriction enzyme Hae III showed that the T-RFs of various size appeared evenly in the 32 clones of KD3 and 38 clones of KD4 respectively that had been treated with liquid fertilizer containing amino acid(LFcAA) compared to 23 clones of KD2 hat had not been treated with LFcAA. The microbial com- munity structure in KD2 appeared less diverse than those in KD3 and KD4. Analysis of partial sequences for 110 clones from KDI (control), KD2 (non-treated), KD3 (LFcAA 1X), KD4 (LFcAA 2X), respectively, revealed that most bacteria were related with uncultured bacteria in a 16S rDNA sequence similarity range of 91-99% through blast search. Otherwise, the other clones were members of proteobacteria, Acidobacteria, Act-inobacteria, Sphingobacteria and Planctomyces groups. Especially in KD4, members of Alpha Proteobacteria, Rhizobiales, Sphigomonadales, Caulobacterales, Gamma Proteobacteria, the genus Pseudomonas, Betapro-teobacteria, Nitrosomonadales and genus Nitrosospira appeared to be dominant. In addition, Acidobacteria group, Actinobacteria group, Planctomycetacia and Sphingobacteria were also shown. The microbial com-munity structure in Z. japonica soil sprayed with herbicide was affected by LFcAA.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.12-21
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• 2013

To clarify the taxonomic position for Astragalus nakaianus and provide correct scientific name for A. mongholicus cultivar in South Korea, we examined external morphological characters and sequence variations from ITS and five cp non-coding DNA regions. Genetic structure was also analyzed for 61 individuals from three populations using nine microsatellite loci. We found no significant difference between the South Korean cultivar and A. mongholicus var. dahuricus when morphology and ITS sequences were considered. Morphologically, A. nakaianus specimens varied somewhat from A. mongholicus var. mongholicus and var. dahuricus in habit, plant height, and lengths of leaf axis and leaflet. Although sequence data from ITS and cp noncoding DNA regions could not distinguished A. nakaianus from A. mongholicus, microsatellite analysis revealed strong structuring between the cultivar and A. nakaianus. Therefore, we conclude that the South Korean A. mongholicus cultivar should be treated as A. mongholicus var. dahuricus and that A. nakaianus should be merged into A. mongholicus as a variety, i.e., A. mongholicus var. nakaianus.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.1
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• pp.49-57
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• 2002

This study was conducted to find out buffer capacities of forest soils by the treatment of simulated acid rain(SAR) of four forests(Q. spp., P. rigida, P. koraiensis, L. leptolepis) in Kyunghee university's practice forest. All soils of each forest stand were treated by simulated acid rain at the level of pH 3.0, 4.0, 5.0 respectively. The result obtained from this study can be summarized as follows: Soil pH was measured by soil depth of each forest stand. The deeper soil depth was, the higher soil pH was. Also it was appeared that base saturation of sample soils was the highest as 17.42% in P. rigida stand and cation exchange capacity(C.E.C) was the highest as 29.87 me/100 g in Q. spp. stand. for responses of soil leachates to acidification treatment with pH 3.0 simulated acid rain(SAR), as simulated acid rain(SAR)-input was increased, pH value of soil leachates appeared high temporarily, but soon pH value of soil leachates had been low gradually. At the rest of pH 4.0, pH 5.0 treatment, pH value of soil leachates was high proportionably. The amounts of TBC of primary stage had a difference as pH level of simulated acid rain and forest stands. But as simulated acid rain(SAR)-input was increased. Amount of TBC was diminished. Also the amounts of TBC of primary stage in acidification treatment with pH 3.0, 4.0 simulated acid rain(SAR) was higher that of acidification treatment with pH 5.0 simulated acid rain(SAR). These trend showed obvious difference at low soil acidity and high TBC. The amounts of activity Al of primary stage appeared high as increasing the input acidity of simulated acid rain(SAR). Also, by soil depth, the amounts of Activity Al was different between A layer(0-15 cm) and AB layer(0-30 cm). There was considerable the correlation between simulated acid rain-input and activity Al change. But this was oppositional trend in soil leachates of pH 4.0, 5.0 treatment and total base cations(TBC).