• Food Science and Preservation
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• v.22 no.5
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• pp.751-757
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• 2015

The objective of this study was to investigate the protective effects of mulberry (Morus alba) sugar extracts (MSE) against $H_2O_2$-induced oxidative stress in HepG2 cells. The MSEs was mixed with matured mulberry and sugar at the same ratio (1:1, w/w) and stored at $18{\pm}3^{\circ}C$ for 40 days. In 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging test, MSE stored for 40 days showed high activity with a ratio above 66%. Therefore, we selected 40 days as the optimum storage period. After cell viability analysis using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, we determined that the optimum concentration of MSE was 0.5%. Our results showed that MSE increased the cell viability and antioxidant enzyme activities of superoxide dismutase (SOD) and catalase in $H_2O_2$-treated HepG2 cells. Moreover, the treatment with MSE inhibited malondialdehyde (MDA) levels in $H_2O_2$-treated HepG2 cells. We also observed a reduction in apoptotic bodies in the Hoechst staining. These data show that MSE treatment significantly suppressed caspase-3 activity in HepG2 cells expored to $H_2O_2$-induced oxidative stress, thereby indicationg the protective effects of MSE in $H_2O_2$-induced oxidative stress.

• KSBB Journal
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• v.31 no.4
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• pp.312-314
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• 2016

This study was carried out to determine the antifungal activity of $SeO_2$ against pathogenic fungus, Candida albicans. Concentration-dependent Inhibitory activity of $SeO_2$ against C. albicans was shown. When $400{\mu}g/disc$ of $SeO_2$ was tested, the inhibition size ranged from 20.7 to 26.8 mm (avg. 23.4 mm). MIC values of $SeO_2$ against cell growth of C. albicans ranged from 50 to $100{\mu}g/mL$ (avg. $70{\mu}g/mL$). These results could be applied to antibiotics-resistant C. albicans and other pathogenic fungi.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.313-316
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• 2001

이동전화 서비스에 있어서 가장 중요한 것 중 하나가 H/O이다. 그동안 동일 세대간$(2G\leftrightarrow2G)$ H/O를 위해 소프트 H/O방식과 소프터 H/O방식이 이용되어 왔으며 별다른 문제점이 없었다. 그러나 사용자의 욕구와 통신기술의 발달로 세대가 다른 시스템이 공존하여 서비스를 시작하므로써 세대간$(2.5\leftrightarrow2G)$ H/O를 위해 파이롯 비컨 방식과 주기형 비컨 방식이 이용되어 왔으나 비경제적이고 능률적이지 못하였다. 이를 개선하기 위해 2001년 4월 ENHHO방식이 개발되어 현재 이용되고 있다. 이 방식 또한 파이롯 신호가 5개 이상인 경우 H/O가 진행되는 동안 통화정보가 순간적으로 단절되는 단점을 갖고 있다. 따라서 본 논문에서는 ENHHO방식의 문제점을 개선하기 위한 알고리즘을 제안하고 이를 이용한 현장측정 결과를 분석하므로써 그 타당성을 검증하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.3
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• pp.116-120
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• 2006

We have investigated plasma spray coated $Al_2O_3$ layers on Al-60 series substrates for development of wafer electrostatic chuck in semiconductor dry etching system. Samples were prepared without/with cooling bar on backside of samples, at various distances, and with different powder feed rates. There were many cracks and pores in the $Al_2O_3$ layers coated on Al-60 series substrates without cooling bar on the backside of samples. But the cracks and pores were almost disappeared in the $Al_2O_3$ layers on Al-60 series substrates coated with cooling bar on the back side of samples, 15 g/min. powder feed rate and various 60, 70, 80 mm working distances. Then the surface morphology was not changed with various working distances of 60, 70, 80 mm. When the powder feed rate was changed from 15 g/min to 20 g/min, the crack did not appear, but few pores appeared. Also the $Al_2O_3$ layer was coated with many small splats compared with $Al_2O_3$ layer coated with 15 g/min powder feed rate. The deposited rate of $Al_2O_3$ layer was higher when the process was done without cooling bar on the back side of sample than that with cooling bar on the back side of sample.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.42-47
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• 2007

Effect of chlorine dioxide ($ClO_2$) treatment on the microbial and physicochemical changes of fish paste was investigated. Fish paste samples were treated with 5, 10, and 50 ppm of $ClO_2$ solution, respectively, After $ClO_2$ treatment, fish paste samples were individually packaged and stored at 4$^{\circ}C$. The initial microbial loads of samples were 3.8 log CFU/g in total bacterial count, and 2.5 log CFU/g in yeasts and molds. Microbial growth of fish paste during storage showed that populations of total bacteria, yeast and mold were significantly reduced by $ClO_2$ treatment. In particular, the treatment of 50 ppm $ClO_2$ decreased total bacterial count the most significantly among the $ClO_2$ treated fish pastes. The pH and VBN of fish paste decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of treated fish paste increased during storage, regardless of $ClO_2$ concentration. This study showed that 50 ppm chloride dioxide was the optimum dose level to extend the shelf-life of fish paste.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.13-13
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• 2019

Soybean (Glycine max L. (Merr) is commonly consumed and found in major foods including soymilk, soy sauce, tofu, and soy sprout in Korea and east Asia. In addition, it is common to cook the whole seeds with rice. Soybean is known to have ranges of health benefits including antiaging, anticancer, neuroprotective and antidiabetic taken either as supplement or dietary food. Anthocyanins and flavonoids in G. max are found to be the main contributors to such wide arrays of health benefits. Due to increasing economic values of soybean, development of specialty soybean cultivars is becoming an area of interest worldwide. In this study, 746 black soybean accessions from National Agrobiodiversity Center were characterized as part of an attempt to identify important germplasms of G. max. Seed coats of each accession were analyzed for their total anthocyanin, cyanidin 3-O-Glucoside (C-3-O-G), delphinidin 3-O-glucoside (D-3-O-G), petunidin-3-O-glucoside (Pt-3-O-G), and their whole seeds for crude protein contents. HPLC was used to determine and quantify the anthocyanin compositions while crude protein was determined using Kjeldahl method by Kjeltec auto-analyzer (Kjeltec 8400, Foss, Sweden). Accessions were grouped according to their anthocyanins and protein contents; the mean content of which were correlated to agronomic traits including maturity date, one hundred seed weight, cotyledon color and seed lust color. The results indicated that the total anthocyanin content (TAC) ranged from 273.77 to 6250.52 mg/100 g, with mean value of 1853.03 mg/100 g while the crude protein content (CPC) being between 33.43 and 47.51%, with mean value of 40.81%. The highest number of accessions (45.97%) showed TAC between 1000~1900 mg/100 g while 30.96% of accessions showed CPC between 41~43%. Among the 746 accessions considered, 11 (IT142935, 175818, 175855, 177191, 177209, 177211, 177214, 177216, 177218, 177220, 177274) of them showed TAC above 4000 mg/100 g. C-3-O-G was found to be the major contributor to TAC showing strong correlation. Accessions with green cotyledon color showed high mean TAC compared to those having yellow cotyledon color, and accessions with dull seed lust color showed high mean TAC than those having shiny seed lust color. One hundred seeds weight and maturity date showed positive correlation with all anthocyanin contents, except for Pt-3-O-G in the latter case. The overall result of the present study could be used as background for developing new black soybean cultivars and breeds with high anthocyanin and protein contents. The result depicted that many of the accessions could be used as potential parental lines.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1052-1057
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• 2005

Recently, the ozone treatment of wasting activated sludge has become one of the effective and feasible process for the sludge reduction. The objective of this study is to investigate the availability of ozonized wasting sludge on external carbon sources 13r phosphorus release. Experiment results showed that the ozone treatment of activated sludge could produce a large amount of VFA such as acetic acid and isobutyric acid. For example, 50.24 mg/L acetic acid was produced with the ozone dose of 0.05 g $O_3/g$ SS, and 123.56 mg/L acetic acid with 0.5 g $O_3/g$ SS. The higher ozone dose was applied, the more VFA was produced from sludge reduction into a limited point. Finally, using ozonated sludge as only carbon source, the batch experiment, to measure phosphorus release rate in anaerobic condition were performed. The specific phosphorus release rates were investigated as 0.94, 1.37, 1.48, 1.68 mg P/g VSS/hr with ozone dose of 0.05, 0.1, 0.2, 0.5 g $O_3/g$ SS, respectively. Considering the degree of mineralization, VFA production, phosphorus release rate, and economical aspect, the optimal ozone dose for sludge reduction and using carbon sources ranged from 0.05 to 0.1 g $O_3/g$ SS.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.453-458
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• 2019

Synthesis of ZnCo₂O₃ oxide is performed by sol-gel method via nitrate-citrate route. Powder X-ray diffraction (XRD) study shows monoclinic unit cell having lattice parameters: a = 5.721(1) Å, b = 8.073(2) Å, c = 5.670(1) Å, β = 93.221(8)°, space group P_2/m and Z = 4. Average crystallite sizes determined by Scherrer equation are the range ~14-32 nm, whereas SEM micrographs show nano-micro meter size particles formed in ZnCo₂O₃. Endothermic peak at ~798 K in the Differential scanning calorimetric (DSC) trace without weight loss could be due to structural transformation and the endothermic peak ~1143 K with weight loss is due to reversible loss of O₂ in air atmosphere. Energy Dispersive X-ray (EDX) analysis profile shows the presence of elements Zn, Co and O which indicates the purity of the sample. Magnetic measurements in the range of +12 kOe to -12 kOe at 10 K, 77 K, 120 K and at 300 K by PPMS-II Physical Property Measurement System (PPMS) shows hysteresis loops having very low values of the coercivity and retentivity which indicates the weakly ferromagnetic nature of the oxide. Observed X-band EPR isotropic lineshapes at 300 K and 77 K show positive g-shift at g_iso ~2.230 and g_iso ~2.217, respectively which is in agreement with the presence of paramagnetic site Co²⁺(3d⁷) in the oxide. DC conductivity value of 2.875 ×10^-8 S/cm indicates very weakly semiconducting nature of ZnCo₂O₃ at 300 K. DRS absorption bands ~357 nm, ~572 nm, ~619 nm and ~654 nm are due to the d-d transitions ⁴T_1g(⁴F)→²E_g(²G), ⁴T_1g(⁴F)→⁴T_1g(⁴P), ⁴T_1g(⁴F)→⁴A_2g(⁴F), ⁴T_1g(⁴F)→⁴T_2g(⁴F), respectively in octahedral ligand field around Co²⁺ ions. Direct band gap energy, E_g~ 1.5 eV in the oxide is obtained by extrapolating the linear part of the Tauc plot to the energy axis indicates fairly strong semiconducting nature of ZnCo₂O₃.

• KSBB Journal
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• v.14 no.2
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• pp.167-173
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• 1999

A new synthetic medium was developed for the submerged mycelial cultures of Phellinus linteus. The medium for maximum mycelial growth of Phellinus linteus (3 days incubation, 28$^{\circ}C$, pH 5) consisted of (per 1 L): glucose, 90 g peptone, 10 g soluble starch, 10 g yeast extract, 3 g KH2PO4, 1 g MgSO4.7H2O, 1 g and CaCl2, 0.1 g. The concentrations of glucose, peptone, yeast extract, KH2PO4, MgSO4.7H2O, and CaCl2 were examined in the ranges of 10~90 g/L, 0~10 g/L, 0~15 g/L, 0~2 g/L, 0~1 g/L, and 0~0.5 g/L, respectively. The dry weight of mycelium in 3 days increased to 16.79 mg/mL using the new synthetic medium. The optimum temperature for mycelial growth of Phellinus linteus was 28$^{\circ}C$. The concentrations of KH2OP4, CaCl2, and yeast extract, which gave the maximum mycelial growth of Phellinus linteus, existed in the concentration ranges examined in this study. But, in the cases of other compositions (MgSO4.7H2O, peptone, and glucose), the mycelial growth of Phellinus linteus increased with the concentration in the ranges.

• Journal of the Korean Electrochemical Society
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• v.5 no.1
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• pp.21-26
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• 2002

A supercapacitor was developed using an amorphous ruthenium oxide material. The electrode of supercapacitor was prepared using an amorphous ruthenium oxide, which was synthesized from ruthenium trichloide hydrate$(RuCl_3{\cdo5}xH_2O)$. Thin film of tantalum was used as a current collector because it had wide. potential window characteristics than titanium and 575304 materials. A supercapacitor was assembled with ruthenium oxide as an electrode active material and 4.8M sulfuric acid solution as an electrolyte. The specific capacitance of the electrode was tested by a cyclic voltammetry using a half cell. The maximum differential specific capacitances during the oxidative and the reductive scans were 710 and $645\;F/g-RuO_2{\cdot}nH_2O$, respectively. The average specific capacitance was $521\;F/g-RuO_2{\cdot}nH_2O$. The assembled supercapacitor was protonated to the potential level of 0.5V vs. SCE. Super-capacitor, which was adjusted to the appropriate protonation level, had the specific capacitance of $151\;F/g-RuO_2{\cdot}nH_2O$ based on the concept of full cell.