• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.77-77
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• 1998

Present silicon dioxide (SiOz) 떠m as intennetal dielectridIMD) layers will result in high parasitic c capacitance and crosstalk interference in 비gh density devices. Low dielectric materials such as f f1uorina뼈 silicon oxide(SiOF) and f1uoropolymer IMD layers have been tried to s이ve this problem. I In the SiOF ftlm, as fluorine concentration increases the dielectric constant of t뼈 film decreases but i it becomes unstable and wa않r absorptivity increases. The dielectric constant above 3.0 is obtain어 i in these ftlms. Fluoropolymers such as polyte$\sigma$따luoroethylene(PTFE) are known as low dielectric c constant (>2.0) materials. However, their $\alpha$)Or thermal stability and low adhesive fa$\pi$e have h hindered 야1리ru뚱 as IMD ma따"ials. 1 The concept of a plasma processing a찌Jaratus with 비gh density plasma at low pressure has r received much attention for deposition because films made in these plasma reactors have many a advantages such as go여 film quality and gap filling profile. High ion flux with low ion energy in m the high density plasma make the low contamination and go어 $\sigma$'Oss피lked ftlm. Especially the h helicon plasma reactor have attractive features for ftlm deposition 야~au똥 of i앙 high density plasma p production compared with other conventional type plasma soun:es. I In this pa야Jr, we present the results on the low dielectric constant fluorocarbonated-SiOF film d밑JOsited on p-Si(loo) 5 inch silicon substrates with 00% of 0dFTES gas mixture and 20% of Ar g gas in a helicon plasma reactor. High density 띠asma is generated in the conventional helicon p plasma soun:e with Nagoya type ill antenna, 5-15 MHz and 1 kW RF power, 700 Gauss of m magnetic field, and 1.5 mTorr of pressure. The electron density and temperature of the 0dFTES d discharge are measUI벼 by Langmuir probe. The relative density of radicals are measured by optic허 e emission spe따'Oscopy(OES). Chemical bonding structure 3I피 atomic concentration 따'C characterized u using fourier transform infrared(FTIR) s야3띠"Oscopy and X -ray photonelectron spl:’따'Oscopy (XPS). D Dielectric constant is measured using a metal insulator semiconductor (MIS;AVO.4 $\mu$ m thick f fIlmlp-SD s$\sigma$ucture. A chemical stoichiome$\sigma$y of 야Ie fluorocarbina$textsc{k}$영-SiOF film 따~si야영 at room temperature, which t the flow rate of Oz and FTES gas is Isccm and 6sccm, res야~tvely, is form려 야Ie SiouFo.36Co.14. A d dielec$\sigma$ic constant of this fIlm is 2.8, but the s$\alpha$'!Cimen at annealed 5OOt: is obtain려 3.24, and the s stepcoverage in the 0.4 $\mu$ m and 0.5 $\mu$ m pattern 킹'C above 92% and 91% without void, res야~tively. res야~tively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.4
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• pp.307-315
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• 2009

This study was conducted to investigate optimal conditions for preparation of extracts from salmon frame using an autoclave. According to the results of various extraction conditions (extraction method, extraction time, volume and pH of extraction solution, and necessity of re-extracting), higher quality extracts could be prepared by adding salmon frame into 3 times (vol/wt) of water to raw material, and then autoclaving for 4 hrs before filtering extracts with cheese cloth. For efficient use as basic materials of liquid or powder Gomtang, however, fish odor of the extracts prepared under optimal condition should be improved.

• Food Science and Preservation
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• v.23 no.5
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• pp.696-703
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• 2016

The purpose of this study was to determine the optimum re-extraction conditions of ethanol from catechin in Korean green tea (Camellia sinensis L.) using response surface methodology (RSM). The experiments were carried out according to a five level and two variable central composite design (CCD). The two independent variables were solvent ratio to sample content (1, 4, 7, 10, 13 mL/g) and extraction temperature (-20, -10, 0, 10, $20^{\circ}C$) on the dependent variables including yield, epigallocatechin (EGC), epicathchin (EC), epigallocatechingallate (EGCG), epicatechingallate (ECG), total catechin and caffeine. ANOVA results showed that Coefficients of determination ($R^2$) of estimated models for dependent variables were ranged from 0.9054~0.9778, while $R^2$ of caffeine were estimated 0.8770. The optimum ranges for the maximized extraction including yield, EGC, EC, EGCG, ECG, caffeine and total catechin were 4.5~7.5 mL/g in ratio of ethanol to sample and $-8{\sim}8^{\circ}C$ in extraction temperature. The actual values of yield, EGC, EC, EGCG, ECG, caffeine and total catechin, respectively, at the optimized conditions were 35.02%, 13.31%, 3.978%, 19.11%, 4.29%, 5.30% and 40.68%.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.131-133
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• 2016

Background: Combination chemotherapy regimes are common treatments for cancer. The aim of this study was to evaluation the effect of individual chemotherapeutic agents in comparison with a first line chemotherapy regime treatment in the AGS gastric cancer cell line by MTT assay. Materials and Methods: In this experimental study, AGS cells were grown in RPMI-1640 supplemented with 10% fetal calf serum and 100 IU/ml penicillin, and $10{\mu}g/ml$ streptomycinin, under a humidified condition at $37^{\circ}C$ with 5% CO2. All cells were washed with PBS and detached with trypsin, centrifuged and 8000 cells re-plated on to 96- well plates. LD50 doses of Epirubicin, Cisplatin and 5-fluorouracil were added to each well in mono or triple therapy. Anti-proliferative activities were determined by MTT assay after 24, 48 or 72 h. Results: Results of MTT assays showed that there were no significant differences among 3 drugs in monotherapy (p=0.088), but there was significant difference between combination therapy with epirubicin (P=0.031) and 5FU (p=0.013) on cell survival at 24 h. After 48 and 72 hours, cell viability showed significant differences between the 3 drugs (p=0.048 and P=0.000 for 48 and 72 h, respectively) and there was significant difference between combination therapy with epirubicin (P=0.035 and P=0.002 for 48 and 72 h, respectively). Conclusions: The results showed no significant differences between these chemotherapy drugs each given alone, but combination therapy with 3 drugs had significant effects on cell viability in comparison with epirubicin alone.

• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.382-391
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• 2019

Many poultry eggs are discarded worldwide because of infection (i.e., avian flu) or presence of high levels of pesticides. The possibility of adopting egg yolk as a source material to produce polyhydroxyalkanoate (PHA) biopolymer was examined in this study. Cupriavidus necator Re2133/pCB81 was used for the production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) or poly(3HHx), a polymer that would normally require long-chain fatty acids as carbon feedstocks for the incorporation of 3HHx monomers. The optimal medium contained 5% egg yolk oil and ammonium nitrate as a nitrogen source, with a carbon/nitrogen (C/N) ratio of 20. Time course monitoring using the optimized medium was conducted for 5 days. Biomass production was 13.1 g/l, with 43.7% co-polymer content. Comparison with other studies using plant oils and the current study using egg yolk oil revealed similar polymer yields. Thus, discarded egg yolks could be a potential source of PHA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.665-671
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• 2020

The chemical and rheological properties of fucoidan and alginate prepared from different parts of Undaria pinnatifida (sporophyll, frond, stipe) were investigated. The algal materials were extracted with HCl (pH 2.0, 3 h at 70℃) to prepare fucoidan, and the remaining solid was continuously re-extracted with Na₂CO₃ (pH 10.0, 70℃, 3 h) to prepare alginic acid. The fucoidan and alginic acid contents in the sporophyll, frond, and stipe were 11.14%, 3.84%, and 1.73% and 22.04%, 37.14%, and 31.74%, respectively. The content of fucoidan and alginate depends on the part extracted. The fucoidan extracted from the sporophyll mainly consists of fucose and galactose, but the fucoidan extracted from frond and stipe contains mannose in addition to fucose and galactose. Fourier-transform infrared spectroscopy analysis of fucoidan and alginate suggests the presence of sulfate groups (1261 and 840 cm^-1) and carboxyl groups (1626 and 1419 cm^-1), respectively. Alginate solutions (5%) had a low viscosity of 10.84-31.63 mPa·s. The activation energies of fucoidan and sodium alginate were 14.45-18.38 kJ/mol and 18.61-22.06 kJ/mol, respectively. The D-mannuronic acid/L-guluronic acid (M/G) ratios of alginate showed a relatively high (frond, 3.72; stipe, 2.88; and sporophyll, 1.80).

• The Plant Pathology Journal
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• v.17 no.3
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• pp.154-158
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• 2001

A severe root rot of kiwifruit caused by a species of Phytophthora occurred in 1-to 5-year-old vines at the south coast region of Korea in 1997. Infected vines exhibited leaf chlorosis, scorch and defoliation, root and stem rot, and eventual death. The disease was relatively severe in poorly drained lowlands, of which 19 out of 23 fields were damaged by the disease. Meanwhile, only one among 58 upland fields was infected by the disease. Incidence of infected vines reached over 80% in heavily damaged fields and a species of Phytophthora was isolated from inner tissues of roots, stems, and rhizosphere soils of the plants. The causal pathogen was identified as P. drechsleri based on its mycological characteristics. Pathogenicity of the fungus was confirmed by artificial inoculation to seedlings of kiwifruit 'Hayward'. The pathogen was re-isolated from the inoculated plants showing symptoms similar to those observed in the fields. Root rot of kiwifruit caused by P. drechsleri has not been reported previously in Korea.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.385-394
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• 2019

This study was designed as the precedent research to develop improve the HMR type flavored cooked rice, by analyzing the consumer perception and purchase pattern. This will in turn provide base data to that will help in the development of products that meet consumer's convenience and quality demands. An online survey of 247 people (63.5%) in the age of 20 to 60 was conducted on January 2019. For the primary reason of buying those products, the survey respondents chose a convenience of 71.7%. They are likely to buy 1~2 times a month (40.5%) in hypermarkets (63.6%). The channel choice showed meaningful difference between segments (p<0.01). 89.1% of respondents replied that they are willing to purchase frozen flavored cooked rice in the future. The Key Purchasing factor appeared to be the flavor (5.80), while nutrition (4.89) was chosen as the least important factor. For flavor preference, sea food received the highest score (5.05), while radish kimchi flavor received the lowest (4.02) with a meaningful difference by gender and age (p<0.01). Consumers who sought nutrition, convenience and adventure in HMR products had higher willingness to re-purchase. Developing healthy, flavorful, sensory, and enjoyable HMR products will be critical in the fulfillment of diverse consumer needs.

• Journal of the Korean Wood Science and Technology
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• v.52 no.2
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• pp.101-117
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• 2024

The conversion characteristics of the major components of Liriodendron tulipifera were investigated during acid-catalyzed organosolv pretreatment. Glucan in L. tulipifera was slowly hydrolyzed, whereas xylan was rapidly hydrolyzed. Simultaneous hydrolysis and degradation of xylan and lignin occurred; however, after complete hydrolysis of xylan at higher temperatures, lignin remained and was not completely degraded or solubilized. These conversion characteristics influence the structural properties of glucan in L. tulipifera. Critical hydrolysis of the crystalline regions in glucan occurred along with rapid hydrolysis of the amorphous regions in xylan and lignin. Breakdown of internal lignin and xylan bonds, along with solubilization of lignin, causes destruction of the lignin-carbohydrate complex. Over a temperature of 160℃, the lignin that remained was coalesced, migrated, and re-deposited on the surface of pretreated solid residue, resulting in a drastic increase in the number and content of lignin droplets. From the results, the characteristic conversions of each constituent and the changes in the structural properties in L. tulipifera effectively improved enzymatic hydrolysis in the range of 140℃-150℃. Therefore, it can be concluded that significant changes in the biomass recalcitrance of L. tulipifera occurred during organosolv pretreatment.

• Journal of Ginseng Research
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• v.44 no.6
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• pp.757-769
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• 2020

Background: Panax quinquefolius and Panax notoginseng are widely used and well known for their pharmacological effects. As main pharmacological components, saponins have different distribution patterns in the root tissues of Panax plants. Methods: In this study, the representative ginsenosides were detected and quantified by desorption electrospray ionization mass spectrometry and high-performance liquid chromatography analysis to demonstrate saponin distribution in the root tissues of P. quinquefolius and P. notoginseng, and saponin metabolite profiles were analyzed by metabolomes to obtain the biomarkers of different root tissues. Finally, the transcriptome analysis was performed to demonstrate the molecular mechanisms of saponin distribution by gene profiles. Results: There was saponin distribution in the root tissues differed between P. quinquefolius and P. notoginseng. Eight-eight and 24 potential biomarkers were detected by metabolome analysis, and a total of 340 and 122 transcripts involved in saponin synthesis that were positively correlated with the saponin contents (R > 0.6, P < 0.05) in the root tissues of P. quinquefolius and P. notoginseng, respectively. Among them, GDPS1, CYP51, CYP64, and UGT11 were significantly correlated with the contents of Rg1, Re, Rc, Rb2, and Rd in P. quinquefolius. UGT255 was markedly related to the content of R1; CYP74, CYP89, CYP100, CYP103, CYP109, and UGT190 were markedly correlated with the Rd content in P. notoginseng.