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Study on the Manufacturing techniques & Conservation of Iron Pot from Cheonmachong Ancient Tomb (천마총 출토 철부(鐵釜)의 제작기법 및 보존처리)

  • Lee, Seung Ryul;Shin, Yong Bi;Jung, Won Seob
    • Journal of Conservation Science
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    • v.30 no.3
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    • pp.263-275
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    • 2014
  • It's shown how to proceed the study on Manufacturing techniques & Conservation to the Iron Pot from Cheonmachong Ancient Tomb(the 155th Tomb in Hwangnam-dong). In order to investigate manufacturing techniques of the Iron Pot, some parts of the relic were gathered. After mounting, polishing and etching on the relic, analyzing the metal microstructure was conducted. Also it's conducted a SEM-EDS analysis on the nonmetallic inclusion. White iron structure was observed in the metallurgical structure inspection, SEM-EDS analysis. It seems to be dried slowly at room temperature after casting, doesn't look as particular heat treatment to improve brittleness. It is estimated that it's as the handle seam side were verified about 3cm inch wide, 1.5 thick in center of body, so 2 separate half-completed products was cast with width-type mould. The manufacturing techniques Using white cast iron structure, width-type mould are observable to the Iron Pot excavated from Sikrichong Ancient Tomb & Hwangnamdaechong grand Ancient Tomb around those were constructed the same time. It's able to recognize that it's almost identical manufacturing techniques at that time. Conservation is generically following those are survey of pretreatment, foreign material removal, stabilization, restoration and color matching in the order. cleaning & drying were added to the process as occasion demands. The strengthening treatment were difficult with artifact's volume, low concentration Paraloid NAD-10 solution was spread two or three times with a brush, surface hardening also came up with 15wt% Paraloid NAD-10 solution after the conservation was complete. There were connection & restoration for the restoration to the damage after modeling forms that it's similar to damaged parts by using the Fiber Reinforced Plastic resins(POLYCOAT FH-245, mold laminated type). Throughout this research, capitalizing on accumulations of measurements about the production technique of Iron Pot in the time of the fifth and 6th centuries is no less important than the Iron artifact's conservation for a better study in the future.

FRACTURE RESISTANCE OF THE THREE TYPES OF UNDERMINED CAVITY FILLED WITH COMPOSITE RESIN (복합 레진으로 수복된 세 가지 첨와형태 와동의 파절 저항성에 관한 연구)

  • Choi, Hoon-Soo;Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.33 no.3
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    • pp.177-183
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    • 2008
  • It was reported that esthetic composite resin restoration reinforces the strength of remaining tooth structure with preserving the natural tooth structure. However, it is unknown how much the strength would be recovered. The purpose of this study was to compare the fracture resistance of three types of undermined cavity filled with composite resin with that of non-cavitated natural tooth. Forty sound upper molars were allocated randomly into four groups of 10 teeth. After flattening occlusal enamel, undermined cavities were prepared in thirty teeth to make three types of specimens with various thickness of occlusal structure (Group $1{\sim}3$). All the cavity have the 5 mm width mesiodistally and 7 mm depth bucco-lingually. Another natural 10 teeth (Group 4) were used as a control group. Teeth in group 1 have remaining occlusal structure about 1 mm thickness, which was composed of mainly enamel and small amount of dentin. In Group 2, remained thickness was about 1.5 mm, including 0.5 mm thickness dentin. In Group 3, thickness was about 2.0 mm, including 1 mm thickness dentin. Every effort was made to keep the remaining dentin thickness about 0.5 mm from the pulp space in cavitated groups. All the thickness was evaluated with radiographic Length Analyzer program. After acid etching with 37% phosphoric acid, one-bottle adhesive (Single $Bond^{TM}$, 3M/ESPE, USA) was applied following the manufacturer's recommendation and cavities were incrementally filled with hybrid composite resin (Filtek $Z-250^{TM}$, 3M/ESPE, USA). Teeth were stored in distilled water for one day at room temperature, after then, they were finished and polished with Sof-Lex system. All specimens were embedded in acrylic resin and static load was applied to the specimens with a 3 mm diameter stainless steel rod in an Universal testing machine and cross-head speed was 1 mm/min. Maximum load in case of fracture was recorded for each specimen. The data were statistically analyzed using one-way analysis of variance (ANOVA) and a Tukey test at the 95% confidence level. The results were as follows: 1. Fracture resistance of the undermined cavity filled with composite resin was about 75% of the natural tooth. 2. No significant difference in fracture loads of composite resin restoration was found among the three types of cavitated groups. Within the limits of this study, it can be concluded the fracture resistance of the undermined cavity filled with composite resin was lower than that of natural teeth, however remaining tooth structure may be supported and saved by the reinforcement with adhesive restoration, even if that portion consists of mainly enamel and a little dentin structure.

A Study on the Sanitary Status at Various Types of Restaurants in Changwon City (창원시 식품접객업소의 위생실태에 관한 조사연구)

  • 이경혜;류은순;이경연
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.4
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    • pp.747-759
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    • 2001
  • The sanitary status of 264 restaurants was investigated to develop a program of sanitary education at restaurants for improving sanitary levels of restaurant and consumers’ food safety. This investigation was performed through direct interviews on general items and sanitations for employees, facilities, equipments and food treatment. The restaurants are grouped into four different types according to the food served: Korean style food, Japanese style raw fish, roasted ribs, and western style food. It is found that sanitary education for employees are conducted at 66.5% of the total restaurants. The highest percentages are obtained by Korean style food restaurants (83.1%) and the lowest by western style food restaurants (55.6%).Washing facilities for employees are equipped at only 66.8% of the total restaurants. In the personal sanitation, 96.6% of the employees wash their hand after touching a dirty stuff, 77.5% after touching money and 57.1% after using telephone. It is also revealed that during food preparation shoes, overgarments, and caps are worn by 58.5%, 55.5%, and 20.6% of the employees, respectively. 73.5% of the restaurants are equipped with dish storages facilities while only 59.2% of restaurants have sterilizers for dishes. Also, chopping boards are sterilized more than once a week by 74.8% of them and knives everyday by 71.6%, 15.4% of restaurants sterilize their knives only once a week. 56.8% of restaurants check temperatures of the refrigerators and 26.2% of restaurants do not even sterilize the refrigerators. 31.8% of restaurants sterilize the kitchens with sodium hopochlorite after cooking. 93.3% of the restaurants store the raw food and the cooked foods separately. 49.8% of the restaurants refroze thawed food and 19.4% of the restaurants reuse leftovers. The frozen foods are thawed at room temperature by 49.4% of the total restaurants and 66.7% of the roasted rib restaurants.

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Effects of 1 keV $Ar^+$ ion irradiation on Au films on glass (1 keV $Ar^+$ 이온의 조사가 유리기판위의 금 박막의 미치는 영향)

  • Jang, H. G.;Kim, H. S.;Han, S.;Choi, W. K.;Koh, S. K.;Jung, H. J.
    • Journal of the Korean Vacuum Society
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    • v.5 no.4
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    • pp.371-376
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    • 1996
  • Au films with a thickness around 1600 $\AA$ were deposited onto glass at room temperature by ion beam sputtering with a 5 cm cold-hollow ion gun at pressure $1\times 10^{-6}-1\times 10^{-5}$ Torr. Irradiation of the Au deposited samples was carried out at pressure of $7\times 10^{-6}$ Torr. For the sputter depositions, $Ar^+$ ion energy was 1 keV, and the current density at the substrate surface was 15 $\mu$A/$\textrm{cm}^2$. Effects of 1 keV $Ar^+$ ion dose($I_d$) between $1\times 10^{16}\; and\;2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$on properties such as crystallinity, surface roughness and adhesion, etc. of the films have been investigated. The Au films sputtered by $Ar^+$ ion beam had only (111) plane and the X-ray intensity of the films decreased with increase of $I_d$. The thickness of Au films reduced with Id. $R_{ms}$ surface roughness of the films increased from 16 $\AA$ at as-deposited to 1118 $\AA$ at ion dose= $2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$. Adhesion of Au film on sputtered at $I_d$= $2\times 10^{17}\;Ar^+\textrm{cm}^{-2}$ was 9 times greater than that of Au film with untreated, as determined by a scratch test.

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Characteristics of ω-3 and ω-6 Balanced Polyunsaturated Fatty Acid Oil Mixture Using Flaxseed Oil and Sesame Oil (아마인유와 참기름을 이용하여 제조한 ω-3와 ω-6 지방산이 균형 잡힌 다가불포화지방산 혼합유의 특성)

  • Byun, Myung-Woo;Chun, Myoung-Sook;Lee, Gyu-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.12
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    • pp.1865-1870
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    • 2014
  • To synthesize ${\omega}$-3 and ${\omega}$-6 balanced polyunsaturated fatty acid (PUFA) oil mixture, flaxseed oil and sesame oil were mixed and their anti-oxidative and sensory characteristics analyzed. For the fatty acid composition analysis results, the ${\omega}$-3 and ${\omega}$-6 PUFA ratios of the F20S80 oil mixture (flaxseed oil 20% and sesame oil 80% oil mixture) and F10S90 (flaxseed oil 10% and sesame oil 90% oil mixture) were represented as 1 to 10 and 1 to 5 ratio for ${\omega}$-3 and ${\omega}$-6 PUFA content from 4.4% to 42.1% and 8.9% to 39.7%, respectively. Since these were within 1:4~1:10 for healthy functional ${\omega}$-3 and ${\omega}$-6 balanced PUFA oil mixtures, these oil mixtures were healthy functional oil mixtures. To analyze anti-oxidative effects, acid values were analyzed. Samples were stored at room temperature, 70% relative humidity (RH) and $45^{\circ}C$, and 70% RH for 16 weeks. The acid value between F10S90 and S100 stored at $45^{\circ}C$ and 70% RH for 16 weeks were not statistically significant. The sensory characteristics such as oxidative odor and sesame odor and taste were not statistically significant among F20S80, F10S90, and sesame S100. Sensory characteristics between F10S90 and S100 stored at $45^{\circ}C$ and 70% RH for 16 weeks were not statistically significant. In conclusion, the sensory and oxidative characteristics of F10S90 were similar to those of S100. Therefore, F10S90 oil mixture should be used as a ${\omega}$-3 and ${\omega}$-6 balanced PUFA healthy functional oil mixture with high anti-oxidative effects.

Effects of Seed Storage Methods and Shading on Seed Germination and Seedling Growth of Endangered Species, Iris dichotoma and Iris setosa (종자저장방법 및 차광처리가 희귀식물 대청부채와 부채붓꽃의 발아와 유묘생육에 미치는 영향)

  • Lee, Su Gwang;Kim, Hyo Yun;Lee, Ki Cheol;Ku, Ja Jung
    • Journal of Korean Society of Forest Science
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    • v.104 no.1
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    • pp.60-66
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    • 2015
  • This study was conducted to determine the effects of seed storage method ($-20^{\circ}C$, $2^{\circ}C$ dry, $2^{\circ}C$ wet 30 days, $2^{\circ}C$ wet 60 days, stratification and room temperature) and shading treatment(control, 50%, 80%) on seed germination, seedling growth of endangered species, Iris dichotoma and Iris setosa. As a result, seed germination rate of I. dichotoma was the highest at 75% when seed were stored at $2^{\circ}C$ wet 60 days and then sown under non-shading condition. The seed of I. dichotoma belong to intermediate seed. Seed germination rate of I. setosa was the highest at 95% when seed were stored at $2^{\circ}C$ wet 60 days and then sown under 80% shading condition. The seed of I. setosa belong to recalcitrant seed. Seedlings of I. dichotoma and I. setosa showed not only the best seedling quality but also seedling vigor index in seed stored at $2^{\circ}C$ wet 60 days under non-shading condition, with the growth characteristics of plant height (6.4, 7.2 cm), number of leaves (3, 4), leaf width (4.6, 3.2 mm), leaf length (5.7, 6.8 cm), fresh weight (aerial/root part; 144/260, 97/153 mg), dry weight (aerial/root; 31/20, 17/17 mg) and seedling vigor index and modified seedling vigor index (13,895/9,479, 13,256/8,668). In this research, I. dichotoma and I. setosa seed were stored at $2^{\circ}C$ wet 60 days, and then sown in non-shading condition, seed germination rate was more than 75%, 90%, respectively, and production of superior quality seedlings.

Changes in the Quality of Beef Jerky Containing Additional Red Wine (적포도주를 첨가한 우육포의 저장 중 품질 변화)

  • Jung, In-Chul;Park, Hyun-Sook;Lee, Kyung-Soo;Choi, Young-Jun;Park, Sung-Sook;Moon, Yoon-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.5
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    • pp.789-796
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    • 2008
  • This study was carried out to investigate the effect of the addition of red wine on the color, water activity, hardness, pH, 2-thiobarbituric acid (TBARS) value, volatile basic nitrogen (VBN) content and total plate count of beef jerky during storage at room temperature for 4 weeks. Beef jerky was prepared using three variations: beef jerky containing 50 mL water (T0), beef jerky containing a combination of 25 mL water and 25 mL red wine (T1) and beef jerky containing 50 mL red wine (T2). The lightness ($L^*$) was the lowest at the 4-week storage period, and the $L^*$ value of T1 and T2 were lower than that of T0 (p<0.05). The redness ($a^*$) tended to decrease during storage, with the $a^*$ value of T1 and T2 being higher than that of the T0 (p<0.05). The yellowness ($b^*$) during storage was not changed, and the $b^*$ value was not significantly different among the different samples tested. The water activity decreased during storage and T0, T1 and T2 was 0.57, 0.57 and 0.60 after 4 weeks of storage, respectively(p<0.05). The hardness increased during storage and the hardness of T2 stored for 4 weeks was lower than that of T0 and T1 (p<0.05). The pH was decreased with an increase in storage time (p<0.05). The TBARS value increased during storage and the TBARS value of T1 and T2 stored for 4 weeks was lower than that of T0 (p<0.05). The VBN content increased during storage and T2 stored for 4 weeks showed the lowest (p<0.05). The total plate count tended to increase during storage, and T0 stored for 4 weeks showed the highest (p<0.05).

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The Effect of Deodeok Contents on the Quality of Deodeok Wine (더덕 함량이 더덕 침출주의 품질에 미치는 영향)

  • Kwon, Dong-Jin;Choi, Shin-Yang
    • Food Science and Preservation
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    • v.14 no.4
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    • pp.414-418
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    • 2007
  • The physicochemical characteristics and sensory properties of Deodeok wine, formed by leaching of Deodeok at room temperature for 180 days, were investigated over the following range of Deodeok levels: 10, 15 and 20% (all w/v). The higher the level of Deodeok, the greater were the final values of total sugars, reducing sugars, total polyphenols, and crude saponins. The Hunter's b-value (yellowness) of Deodeok wine varied markedly with Deodeok levels, and yellowness was highest in Deodeok wine containing 20% (w/v) Deodeok. Non-volatile compounds, that form the basis of the liquor tax law, were 0.64, 1.38 and 2.11% (all w/v), respectively, at day 160. Of these values, that of 2.11% (w/v), the level of non-volatile compounds in Deodeok wine containing 20% (w/v) Deodeok, was in accord with the liquor tax law (that requires this figure to be 2.0%). Sensory evaluation showed that Deodeok wine containing 20% (w/v) Deodeok was superior to the other wines tested.

Onion Favorably Affects Serum Markers of Ethanol-induced Fatty Liver in Rats (흰쥐에서 양파추출물의 알코올성 지방간 개선 작용)

  • Shin, Hye-Kyoung;Seo, Yun-Jung;Kim, Ju-Youn;Kim, Chang-Sun;Noh, Sang-K.
    • Food Science and Preservation
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    • v.14 no.6
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    • pp.662-668
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    • 2007
  • Studies have shown that onions exhibit a wide variety of health-promoting properties. The health benefits by the onion have been attributed to its ability to scavenge free radicals, to reduce blood lipids, to lower blood pressure, and to inhibit platelet aggregation. This study was performed to investigate whether onion extract supplementation would affect the blood markers of ethanol-induced fatty liver in rats. Initially, male Sprague-Dawley rats were housed singly in a room of controlled temperature and lighting and had free access to a nutritionally adequate AIN-93G and deionized water. The rats were trained for meal feeding to prevent a decline in food intake, as inevitably observed following an ethanol feeding. After the training period, rats were weight-matched and assigned to the following three groups: 1) a control group, fed the AIN-93G diet alone (control); 2) an ethanol group, fed the AIN-93G diet with ethanol at 4 g/day/kg body weight (ethanol); and 3) an onion group, fed the AIN-93G diet with ethanol plus supplemental freeze-dried onion powder at 500 mg/day/rat (ethanol + onion). All three group were meal-fed 7.0 g of their respective diets at 0900 h and 7.5 g at 1600 h for 28 days. At 0, 2, and 4 wk, blood was collected via the orbital sinus and organs were collected following overnight food deprivation. Both control and experimental groups continually gained weight throughout the study. No significant differences in the weights of the liver, kidneys, heart, spleen, and testis were observed. However, the serum level of triglycerides was significantly increased by ethanol but significantly decreased by onion extract. The activities of serum glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) at 4 wk were significantly increased by ethanol feeding but were significantly decreased by onion supplementation. However, no differences among groups were observed in the serum levels of alkaline phosphatase, gamma-glutamyl transpeptidase, bilirubin, and protein. These results provide that onion extract favorably affect alcoholic fatty liver by decreasing the serum concentration of triglyceride and the activities of GOT and GPT.

Antioxidant and anti-aging activities of water extracts from Chionanthus retusus flesh according to different extraction temperatures (추출온도에 따른 이팝나무 과육 물 추출물의 항산화 및 항노화 활성)

  • Choi, Hae-Sim;Lee, Yang-Suk;Seo, Su-Jeong;Kim, Nam-Woo
    • Food Science and Preservation
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    • v.24 no.8
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    • pp.1129-1137
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    • 2017
  • The fringe tree, Chionanthus retusus (Oleaceae) has been used as a natural remedy that helps a paralytic stroke, dementia, phlegm and malaria. This study was conducted to investigate the antioxidant and anti-aging activities of water extracts obtained from the flesh of C. retusus by reflux extraction at room temperature and $80^{\circ}C$, and pressure heating extraction at $110^{\circ}C$, for an increment of their practical use. The highest extraction yield from the flesh of C. retusus was 67.94% extract by pressure heating extraction at $110^{\circ}C$. The content of total polyphenol compounds was the highest by 72.71 mg/g in $80^{\circ}C$ extract by reflux extraction. The highest content of total flavonoid compounds was 7.60 mg/g at $110^{\circ}C$ extract. The results of soluble protein and reducing sugar contents showed the highest content of 4.93 mg/g and 46.77 mg/g in $110^{\circ}C$ extract, respectively. In the analysis of DPPH radical scavenging activity, all extracts showed an excellent effect of 92% in 1.0 mg/mL concentration. The highest effect of ABTS radical scavenging activity was 88.67% at $110^{\circ}C$ extraction in 1.0 mg/mL concentration. Nitrite scavenging ability was the highest as 66.16% at $110^{\circ}C$ extract at pH 1.2 and 1.0 mg/mL concentration. The results of SOD-like activity and xanthine oxidase inhibition activities showed the highest effect of 14.95% and 59.45% at $110^{\circ}C$ extract in 1.0 mg/mL, respectively. Tyrosinase inhibition activity for whitening effect was the highest of 35.31% at $85^{\circ}C$ in 1.0 mg/mL. In the analysis of anti-aging effect, collagenase and elastase inhibition activity showed the highest effects of 37.78% at $110^{\circ}C$ and 20.39% at $80^{\circ}C$, respectively. All results of antioxidant activities and anti-aging effects increased along with the concentration increases. These results indicated that the extracts extracted from the flesh of C. retusus at $80^{\circ}C$ and $110^{\circ}C$ have a large amount of useful ingredients, an excellent antioxidant activity, like as DPPH and ABTS radical scavenging activity, and anti-aging effects to develop functional products than those of $25^{\circ}C$.