• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.131-134
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• 2005

The effect of far-infrared (FIR) irradiation on the antioxidant activity of extracts from rice hulls was evaluated. Rice hulls (9 g) were placed in Pyrex petri dishes (8.0 cm diameter) and irradiated at 80, 90, 100, 110, 120, 130 or 14$0^{\circ}C$ for 10,20,30,40,50 or 60 min with a FIR heater, respectively. After FIR irradiation, methanol extract of rice hulls was prepared, and total phenol contents (TPC) and radical scavenging activity (RSA) of the extracts were determined. FIR irradiation of rice hulls at 11$0^{\circ}C$ for 60 min increased TPC of the methanol extract from 51.6 $\mu$M to 104.3 $\mu$M compared to those of non-irradiated control. The irradiation at 12$0^{\circ}C$ for 60 min also increased RSA of the extract from 16.23% to 69.40%. These results indicated that appropriate FIR irradiation onto rice hulls could liberate the covalently bound phenolic compounds that have antioxidant activities.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.82-82
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• 2003

The present study was undertaken to examine the cytotoxic effect of extract of Eurya emarginata against cancer cells and to develop an anti-cancer agent using components of its leaves. The crude extract of its leaves markedly inhibited the growth of leukemia cells including HL-60. When the HL-60 cells were treated with the extract, DNA fragmentation, morphologic changes and sub-Gl hypodiploid cells were observed. Therefore, the inhibitory effect of E. emarginata on the growth of the HL-60 cells appears to arise from the induction of apoptosis. Moreover, the extract markedly reduced c-Myc expression in a time-dependent manner. Eutigoside C showing the cytotoxic effect was isolated from the leaves of E. emarginata. Eutigoside C reduced the Bcl-2 protein and mRNA levels in a time-dependent manner, whereas the Bax protein and mRNA expression levels were slightly increased. When HL-60 cells were treated with eutigoside C, the release of cytochrome C from mitochondria into the cytosol was observed. Also, the expressions of the active forms of caspase 9 and 3 were increased and the activation of caspase 3 was demonstrated by the cleavage of Poly(ADP-ribose) polymerase, a vital substrate of effector caspase. The results indicate that the eutigoside C from E. emarginata induce apoptosis of HL-60 cells via the down-regulation of Bcl-2 expression and activation of caspases.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.73-73
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• 2011

We will report a few methods to improve the efficiency and stability in small molecule based organic solar cells, including the formation of bulk heterojunctions (BHJs) through alternative thermal deposition (ATD), the use of a micro-cavity structure and interface modifications. By ATD which is a simple modification of conventional thermal evaporation, the thicknesses of alternative donor and acceptor layers were precisely controlled down to 0.1 nm, which is critical to form BHJs. The formation of a BHJ in copper(II) phthalocyanine (CuPc) and fullerene (C60) systems was confirmed by AFM, GISAXS and absorption measurements. From analysis of the data, we found that the CuPc|C60 films fabricated by ATD were composed of the nanometer sized disk shaped CuPc nano grains and aggregated C60, which explains the phase separation of CuPc and C60. On the other hand, the co-deposited CuPc:C60 films did not show the existence of separated CuPc nano grains in the CuPc:C60 matrix. The OPV cells fabricated using the ATD method showed significantly enhanced power conversion efficiency compared to the co-deposited OPV cells under a same composition [1]. We will also present by numerical simulation that adoption of microcavity structure in the planar heterojunction can improve the short circuit current in single and tandem OSCs [2]. Interface modifications also allowed us to achieve high efficiency and high stability OSCs.

• Advances in nano research
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• v.4 no.3
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• pp.167-179
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• 2016

The detailed study of acute and sub-acute toxicity of the complex polyvinylpyrrolidon (PVP 20 kDa)-wrapped fullerene $C_{60}$ after intraperitoneal (ip) administration was carried out on adult male Wistar rats. The $LD_{50}$ value of $C_{60}/PVP$ complex was found to be 7, 8 g/kg. In sub-acute study which lasted for 30 days the rats were exposed to daily administration of the complex in the doses of 350 or 700 mg/kg. All animals survived during the study and had no significant changes in clinical signs, organ weight, hematological and biochemical parameters of blood. The electrophysiological properties of myocardium and the excretory function of kidneys remained normal. Histological analysis of liver, kidney and spleen at the end of the study also did not demonstrate toxic alterations. It was thus established that intraperitoneal administration of complex $C_{60}/PVP$ has no toxic effect. These results suggest that $C_{60}/PVP$ has no acute and sub-acute toxicity and is a perspective substance for potential application in biology and medicine.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.1
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• pp.887-894
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• 2018

We investigated the position controlling C60 fullerene encapsulated into a graphene-nanoribbon trench via classical molecular dynamics simulations. The graphene-nanoribbon trench can provide nanoscale empty spaces, and a C60 encapsulated therein can be considered as media for a nanoelectromechanical shuttle device. The classical molecular dynamics simulations presented here provide information on the potential application of a graphene-nanoribbon trench in a C60 shuttle device. Driving forces applied to C60 resulted in its motion toward the edges of the graphene-nanoribbon trench, the suction forces induced at both edges were balanced with the driving forces, and finally, the C60 fullerene gradually settled on the edges of the graphene-nanoribbon trench after several oscillations. The results of the present simulation suggest the importance of graphene-nanoribbon trenches encapsulating fullerenes in a wide range of applications in the field of nanotechnology.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.30-39
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• 1994

To study the printing behaviors of Polyester and cotton(P/C) fabrics printed with disperse and reactive dyes, the effects of alkalis on the fixation of reactive dyes and the alkali-stability of disperse dyes in various methods of fixation were examined. The anthraquinone disperse dyes which have diamino derivatives as substituents without hydroxy group, such as C.I. Disperse Violet 1(D.V.1), C.I. Disperse Violet 28(D.V.28) and C.I.Disperse Blue 60(D.B.60) showed good results of fixation without regard to the concentration of NaHCO$_3$. In case of high temperature steaming(HTS) and unsaturated steaming(US)/HTS, D.V. 1 was alkali-stable and effective for P/C printing. A good result was obtained with D.V.1 and C.I.Reactive Orange 13(R.O.13) paste of 4% $K_{2}CO_{3}$. It was found that the unfixed D.V.28 bearing chloro group can hinder the fixation of monochlorotriaxinyl reactive dyes, and D.B.60 made little stain on 100% cotton. In thermosol(Tm), the dye uptake of D.V.1 was not decreased so much, but those of D.V.28 and D.B.60 were greatly decreased.

• Journal of Biosystems Engineering
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• v.34 no.1
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• pp.30-36
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• 2009

This study was performed to determine the effect of drying conditions on the germination properties of rapeseed after seeds were dried under different drying conditions: $40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$ in combination with 30%, 45%, or 60% relative humidity. As analytic results, drying conditions had significant effects (P-value < 0.001) and drying temperature was considered as the main factor on the germination properties of rapeseed. When drying temperature increased or relative humidity decreased, the vigor rate and germination rate decreased, the median germination time increased. The maximum values of vigor rate and germination rate were 90% and 95.44%, and their minimum values were 60.17 and 75%, respectively. To ensure the standard germination rate of 85%. The appropriate drying zone was determined and the drying temperature should be less than $51.0^{\circ}C$, $54.5^{\circ}C$ and $58.7^{\circ}C$ at 30%, 45% and 60% RH, respectively. The values for median germination time varied from 2 to 4 days. The predicted models of germination rate, vigor rate, and median germination time were determined.

• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.22-28
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• 2004

A new moderate thermophilic bacterial strain DG-22 which produces thermostable xylanase was isolated from a timber yard soil in Kyungju, Korea. On the basis of morphological, biochemical and phylogenetic studies the new isolate was identified as a Paenibacillus species. Production of xylanase in this strain was strongly induced by adding xylan to the growth medium and repressed by glucose or xylose. No cellulase activity was detected. The temperature and pH for optimum activity were 8$0^{\circ}C$ and 5.0-5.5, respectively. The crude xylanase was stable at $60^{\circ}C$ and retained 60% of initial activity after 2h at $70^{\circ}C$. Zymogram analysis of the culture supernatant showed two xylanase active bands with molecular masses of 22 and 30 kDa.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.753-757
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• 2003

The quality characteristics of the traditional Korean snack Yut-gang-jung with Perilla, and the changes that occur during storage were investigated. The water and protein content of a fresh sample were 9.67％ and 10.83％, respectively. The water content in the sample stored at 20$^{\circ}C$ changed slightly, but that of the sample stored at 60$^{\circ}C$ showed larger changes from 9.33 ％ to 4.33％. The acidity of the sample stored for 8 days was significantly higher. The hardness of the sample stored at 60$^{\circ}C$ for 4 days was increased significantly. Results of the sensory evaluation indicated the sample stored at 60$^{\circ}C$ had a significantly decreased roasted perilla flavor. The rancid flavor of the sample stored at 20$^{\circ}C$ increased slightly, while that of the sample stored at 60$^{\circ}C$ showed a drastic increase during storage. Therefore, a one week storage of the Yut-gang-jung with Perilla at room temperature is recommended for a product to have a shelf-life with similar physicochemical and sensory properties to fresh samples.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.11a
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• pp.80-87
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• 2001

The fatigue crack growth behavior of the SA516/60 steel which is used for pressure vessels was examined experimentally at room temperature $25^{\circ}C, -30^{\circ}C, -60^{\circ}C, -80^{\circ}C, -100^{\circ}C$ and -l2$0^{\circ}C$ with stress ratio of R=0.05, 0.1 and 0.3. Fatigue crack propagation rate da/dN related with stress intensity factor range ΔK was influenced by stress ratio in stable of fatigue crack growth (Region II) with an increase in ΔK. The resistance of fatigue crack growth at low temperature is higher compared with that at room temperature, which is attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations reveal that the differences of the fatigue crack growth characteristics between room and low temperatures are mainly explained by the crack closure and the strengthening due to the plasticity induced and roughness induced.