• Journal of Technologic Dentistry
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• v.34 no.2
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• pp.83-93
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• 2012

Purpose: The objective of this study is to find out physical properties and the flexural strength changed by the low temperature degradation of the block which is needed to make bio-prosthetic dentistry which is better than feldspar affiliated ceramic made by building up ceramic powder and also to apply this to the clinical use of zirconia monolithic all-ceramic crown. Methods: Flexural strength of each sample was evaluated before and after the Low Temperature Degradation, and physical properties of the Tetra Zirconia Block containing 3mol % was evaluated as well. The average and standard deviation of each experimental group were came out of the evaluation. Statistical package for social science 18.0 was used for statistics. Results: The average density of the monolithic all-ceramic crown was $6.0280{\pm}0.0147g/cm$, the relative density was 99.01 %. When the sample was sintered at $1480^{\circ}C$ the diameter of average particle was $396.62{\pm}33.71nm$. All the samples had no monolithic peak after XRD evaluation but only had tetragonal peak. There were statistically significant differences in the result of flexural strength of the samples evaluated after and before the low temperature degradation, the flexural strength before the low temperature degradation was $1747.40{\ss}{\acute{A}}$, at the temperature of $130^{\circ}C$ the flexural strength after the low temperature degradation was 1063.99MPa (p<0.001). There was statistically significant difference in the result of strength of 1020.07MPa after the low temperature degradation at the temperature of $200^{\circ}C$ (p<0.001). Conclusion: The block which was made for this evaluation possesses such an excellent strength among dental restorative materials that it is thought to have no problems to use for tetragonal zirconia polycrystal.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.885-890
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• 2010

This study was conducted to confirm the application as ingredients of cosmetics through an examination of the function for anti-oxidant activity of the fraction isolated from Pyrus ussuriensis leaves. The dried leaf of Pyrus ussuriensis were extracted with acetone-$H_2O$ (6:4, v/v), concentrated and fractionated with the upper layer of acetone on a separatory funnel. Each fraction was freeze dried, then a portion of acetone soluble powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol as eluents and also used the MIC-gel using a series of aqueous methanol as developing solvent. The isolated compounds were identified by silica-gel TLC. The concentration of total phenolic compound of Pyrus ussuriensis acetate soluble fraction was high, 914 mg/g. The results obtained from the analyses of the anti-oxidanat effects of Pyrus ussuriensis acetate fraction can be summarized as follows: In the result of DPPH scavenging radical activity, Pyrus ussuriensis acetate soluble fraction showed more than 80% at 100 ppm. SOD-like activity of one of Pyrus ussuriensis acetate soluble fractions was 77% at 1000 ppm. Xanthine oxidase inhibition of Pyrus ussuriensis acetate soluble fraction was 38% at 100 ppm. From these results, we confirmed that acetate fraction of Pyrus ussuriensis has a great potential as a natural ingredients with a natural antioxidant and antimicrobial source.

• Korean Journal of Agricultural Science
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• v.17 no.2
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• pp.130-141
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• 1990

In order to investigate possible utilization as a naturall antioxidant, antioxidative fraction from pueraria root powder was obtained by solvent extraction. PO,CO and TBA values were measured at $60^{\circ}C$, $100^{\circ}C$, $145^{\circ}C$, respectively, after adding the pueraria root extract to the final concentration of 0.1% to the lard, beef tallow, pallm and soybean oil. The results of antioxidative effect of pueraria root extract to edible oils and fats were as follows : 1. Antioxidative fractions in pueraria root were extracted by sequential solvent systems using ethanol, methanol : isopropyl alcohol (1: 4) and chloroform : methanol(95 : 5). 2. Antioxidative activity of the extracts to edible oils and fats was more effective than that of adding 100 ppm $\alpha$-tocopherol at $60^{\circ}C$. 3. At $60^{\circ}C$ and $100^{\circ}C$, antioxidative effect was beef tallow>palm oil>lard>soybean oil in its orders. 4. At $145^{\circ}C$, the pueraria root extract showed antioxidative activity in beef tallow, lard and palm oil, but not in soybean oil. 5. The content of saturated fatty acids by the heat treatment was remained smalll change, but that of unsaturated fatty acids was noticeable decreased.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.581-585
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• 1999

The surface treated hydroxypropyl methylcellulose(HPMC) which could adjust the soluble time was synthesized when 40 wt % glyoxal solution and $KH_2PO_4$ were sprayed and reacted. And also, the solution dynamic at different ratios of two adding agents were identified If the surface of HPMC was treated with only glyoxal, the dispersion characteristics at different ratios of two adding agents were identified If the surface of HPMC was treated with only glyoxal, the dispersion was observed in the neutral solution and the viscosity was increased after directly dissolved as the solution become alkali condition. But the fine-powder type of HPMC which reacted with glyoxal and $KH_2PO_4$ was dispersed regardless of pH of solution and observed that it was dissolved and its viscosity increased after elapsing some time. With increasing amount of glyoxal and $KH_2PO_4$, the soluble time was delayed. The reaction condition was about 60 min at $75{\sim}85^{\circ}C$. Especially, the removal process of organic solvent after reaction was not required due to reaction under water solution without organic during glyoxal and $KH_2PO_4$ treatment. And also, the HPMC which could adjust the soluble rate in water or organic solvent by changing the degree of substitution of HPMC was synthesized.

• Journal of Sensor Science and Technology
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• v.1 no.1
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• pp.59-66
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• 1992

To develop the highly sensitive TLD radiation sensors, $BaSO_{4}$ : Eu-PTFE TLDs are fabricated by polymerizing the PTFE(polytetrafluoroethylene) with $BaSO_{4}$ : Eu TL phosphors. The $BaSO_{4}$ : Eu TL phosphors having the highest sensitivity of $X/{\gamma}$-rays are obtained by sintering at $1000^{\circ}C$ in $N_{2}$ atmosphere a mixture of $BaSO_{4}$ powder with 1mol% Eu($Eu_{2}O_{3}$), 6mol% $NH_{4}Cl$ and 5mol% $(NH_{4})_{2}SO_{4}$ which were co-precipitated in dilute sulfuric acid and then dried. The activation energy, frequency factor and kinetic order of $BaSO_{4}$ : Eu TL phosphor are 1.17eV, $3.6{\times}10^{11}/sec$ and 1.25, respectively. And the spectral peak of $BaSO_{4}$ : Eu is about 425nm. The optimum TL Phosphor content and thickness of the $BaSO_{4}$ : Eu-PTFE TLD are 40wt% and $105.7mg/cm^{2}$. The optimum polymerization temperature and time for fabrication of $BaSO_{4}$ : Eu-PTFE TLDs are $380^{\circ}C$ and 2 hours in air, respectively. The linear dose range to ${\gamma}$ rays is 0.01-20Gy and fading rate is about 10%/60hours.

• Korean Journal of Pharmacognosy
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• v.49 no.2
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• pp.132-137
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• 2018

This study was conducted to investigate the effects of dietary Allium hookeri on growth performance, bone strength, and blood biochemical profiles in growing broiler chickens. Twelve hundreds of one-day old Arbor Acres male broilers were divided into 6 treatments with 4 replicates and 50 birds per replicate (n=200 chicks/treatment). Chickens fed basal diet (Control), basal diet with commercial X (Positive control) at 0.05% of diet, or each one of the experimental diets (L3, L5, R3, R5) supplemented with the powder of A. hookeri leaf or root at 0.3 and 0.5% of diet respectively for 5 weeks. At the 5th week of feeding the diets, body weight, tibia strength, and blood biochemical profiles including antibody titers were measured. Dietary A. hookeri (L3, L5, R3, R5) significantly increased final body weight than the control group. And the dietary leaf of A. hookeri effectively increased the growth performance than dietary root of A. hookeri. Interestingly dietary leaf of A. hookeri improved tibia strength than the control group and L3 showed the highest value. The antibody titers against infectious bursal disease (IBD) increased with the addition of dietary leaf of A. hookeri compared with positive control, R3, and R5 groups. But there was no significant difference in serum biochemical parameters such as albumin, globulin, glucose, cholesterol, Ca, P, total protein, total bilirubin, alanine aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase. These results suggest that A. hookeri can be used as a good supplement to improve growth performance and health by increasing bone strength and antibody titer against IBD without any anti-nutritional or toxic effects in growing broilers.

• Journal of Conservation Science
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• v.25 no.3
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• pp.323-333
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• 2009

The Jincheonsagongnimaaeyeoraeipsang is a great stone relief Buddha in Goryeo Dynasty, transmitting sculptural styles of the Silla Kingdom. The Buddha was carved on the biotite granite basement, and was undergone cleaning treatment in 2007. The basement rock was opened in plenty cracks bringing out structural instability. And the top of the basement rock was colonized by trees obstructing sunshine and raising humidity. As a result of failure analysis, the basement rock of the Buddha had a major possibility of wedge failure in the parts of the face, hands and cloths. Therefore, the cracks were filled up with epoxy resin L-50, and titanium bars and wire ropes were applied to bind cracked rock blocks. The surface of the crack filler was colored by granite and talc powder with inorganic pigment and L-30. The crack meters were installed on the stone relief Buddha to monitor further behavior, lastly.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.271-278
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• 2006

As for red pepper seasoning oil (RPSO), seasoning oil (SO) and pine needle oil (PNO), various organic solvent extracts from rosemary powder and tocopherol are treated as control group. At this time, amounts that are treated were all 1,000 ppm. It was observed by AV (acid value), POV (peroxide value) and carbonyl compounds content of the stored samples during 3 months at 60${\pm}$2$^{\circ}C$ incubation. Tocopherol was shown to be pro-oxidant than the antioxidant in all seasoning oil samples. Icreasing effect of storage stability of chloroform/MeOH extract was the most superior one. Final result of icreasing effect of storage stability from the determinated data was as follows. The storage stability of solvent system by AV and POV analysis was in the increasing order of chloroform/MeOH extract> ethyl alcohol extract>hot water extract>ethyl acetate extract>acetone extract>none treating group> tocopherol treating group, POV was chloroform/MeOH extract>ethyl alcohol extract ${\geq}$ ethyl acetate extract> acetone extract ${\geq}$ hot water extract>none treating group>tocopherol treating group and by carbonyl compound content analysis was in the increasing order of chloroform/MeOH extract>ethyl acetate extract>ethyl alcohol extract>hot water extract>acetone extract>none treating group>tocopherol treating group.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.1-7
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• 2012

In this article, I will introduce recent developments of environmental-friendly materials fabricated using atomic layer deposition (ALD). Advantages of ALD include fine control of the thin film thickness and formation of a homogeneous thin fim on complex-structured three-dimensional substrates. Such advantages of ALD can be exploited for fabricating environmental-friendly materials. Porous membranes such as anodic aluminum oxide (AAO) can be used as a substrate for $TiO_2$ coating with a thickness of about 10 nm, and the $TiO_2$-coated AAO can be used as filter of volatile organic compound such as toluene. The unique structural property of AAO in combination with a high adsorption capacity of amorphous $TiO_2$ can be exploited in this case. $TiO_2$ can be also deposited on nanodiamonds and Ni powder, which can be used as photocatalyst for degradation of toluene, and $CO_2$ reforming of methane catalyst, respectively. One can produce structures, in which the substrates are only partially covered by $TiO_2$ domains, and these structures turns out to be catalytically more active than bare substrates, or complete core-shell structures. We show that the ALD can be widely used not only in the semiconductor industry, but also environmental science.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.131-135
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• 2009

The identification characteristics of irradiated commercial Ramen soup were investigated depending on radiation sources and doses by electron spin resonance (ESR) spectroscopy. Two commercial powder soups (RS-1, RS-2) were irradiated at 0 to 20 kGy under ambient conditions by both a Co-60 gamma irradiator and an electron beam (EB) accelerator, respectively. Crystalline sugar-induced multi-component signals with g-values of 2.010/2.011, 2.006, 2.002 and 1.999 were detected in the irradiated Ramen soup (RS-1, RS-2), whereas $Mn^{2+}$ signals were observed in non-irradiated samples, thereby distinguishing each other. Under the same analytical conditions, the intensity of ESR signals was higher in EB-irradiated samples than the gamma-irradiated ones. Determination coefficients ($R^2$) between irradiation doses and corresponding ESR responses were above 0.9665 in all the samples, and the magnetic field of specified g-value remained constant. The predominant ESR signals of $g_2$ (2.010-2.011) and $g_3$ (2.002) increased with corresponding doses of irradiation ($R^2$= 0.9750-0.9981).