• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.96-104
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• 2008

In this study, the observation of test pieces with an optical microscope was carried out after fabricating 4 groups of standard lacquer, in order to inquire into the ancient lacquering techniques. Group I had transparent reddish brown color, and the part of layer was indefinite, and the layer polished was easily distinguished. Group II had mostly transparent yellowish brown color, and it was possibility distinguished the layers when they were varnished with mixed lacquer after prime coating, and when they were varnished with lacquer as the prime coating. Group III set up membrane in the hardening process of the lacquer, and the lacquer and the unsaturated fatty acid of internal part was dried, so the top layer and the lacquer layer were separated and observed. Group IV: When the lacquer coat film of Group IV test pieces were observed in polarized light, the ferrous components were seen as the black and red color were mixed, and the silica crystals of silty soil were distinguished by reflection of lights. And the colors were distinguished as the lacquer layer of ruddle had red color, and the mixed lacquer of reddish lacquer and ruddle had the deep red color at the top and the bottom, but the middle part had the bright red color.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.222.1-222.1
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• 2015

Recently, graphene quantum dots (GQDs) have attracted great attention due to various properties including cost-effectiveness of synthesis, low toxicity, and high photostability. Nevertheless, the origins of photoluminescence (PL) from GQDs are unclear because of extrinsic states of the impurities, disorder structures, and oxygen-functional groups. Therefore, to utilize GQDs in various applications, their optical properties generated from the extrinsic states should be understood. In this work, we have focused on the effect of oxygen-functional groups in PL of the GQDs. The GQDs with nanoscale and single layer are synthesized by employing graphite nanoparticles (GNPs) with 4 nm. The series of GQDs with different amount of oxygen-functional groups were prepared by the chain of chemical oxidation and reduction process. The fabrication of a series of graphene oxide QDs (GOQDs) with different amounts of oxygen-contents is first reported by a direct oxidation route of GNPs. In addition, for preparing a series of reduced GOQDs (rGOQDs), we employed the conventional chemical reduction to GOQDs solution and controlled the amount of reduction agents. The GOQDs and rGOQDs showed irreversible PL properties even though both routes have similar amount of oxyen-functional groups. In the case of a series of GOQDs, the PL spectrum was clearly redshifted into blue and green-yellowish color. On the other hand, the PL spectrum of rGOQDs did not change significantly. By various optical measurement such as the PL excitation, UV-vis absorbance, and time-resolved PL, we could verify that their PL mechanisms of GOQDs and rGOQDs are closely associated with different atomic structures formed by chemical oxidation and reduction. Our study provides an important insights for understanding the optical properties of GQDs affected by oxygen-functional groups. [1]

• Research in Plant Disease
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• v.8 no.3
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• pp.162-165
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• 2002

Rust disease was found on broad bean (Vuia faba) in several farmer's fields located in Changseon-myon, Nam-hae-gun, Gyeongnam province in Korea. The infection rate of the disease in the surveyed area was 84.3% in 2002. The typical symptoms of the disease appeared first as small, white spots on leaves, stems and pods. Spots, then turn brownish, their edges rised slightly, and powdery mass of yellowish brown spores revealed on them. Severely infected leaves were eventually defoliated. Uredospores were light brown in color, ellipsoid or ovoid in shape and 24~38$\times$21~26 ${\mu}{\textrm}{m}$ in size. Teliospores were dark brown in color, ellipsoid or ovoid in shape and 22~42$\times$17~27 ${\mu}{\textrm}{m}$ in size. Pedicels were sienna to luteous in color and 52~116 ${\mu}{\textrm}{m}$ in size. The causal fungus was identified as Uromyces viciae-fabae, based on morphological characteristics. This is the first report on the rust of broad bean caused by Uromyces viciae-faae in Korea.

• The Journal of the Korean dental association
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• v.54 no.5
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• pp.365-373
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• 2016

Purpose: Cemental tear is a specific type of root surface fracture characterized by a complete separation of a cemental fragment along the cementodentinal junction or a partial split within the cementum along an incremental line. It is suggested to be a factor for periodontal or periapical tissue destruction. The aim of this study is to present a diagnosis and treatment of cemental tear associated with periapical lesion with root canal treatment and regenerative periodontal surgery. Treatments: A 60-year-old male who had a history of sports trauma on the mandibular right central incisor about 10 years ago presented with apical cemental tear. Clinical examination showed a slightly dark yellowish discoloration and sinus tract that was located on the apical labial mucosa. The mobility and percussion were also assessed on the diseased tooth and recorded as $Miller^{\circ}{\phi}s$ Class II and tenderness to percussion. The probing depth was within the normal limit (<3 mm). Radiographic examination revealed a radiolucent lesion at the apical area and extended to distal aspect of the tooth along the fragment of cemental tear. After root canal treatment, periapical surgery was performed. The bony defect was exposed and then the detached root fragment was removed. Apical root resection and retrograde filling with Mineral Trioxide Aggregate (MTA) were accomplished and the bony defect was filled with deproteinized bovine bone mineral (DBBM) and covered with biodegradable collagen membrane. Results: After 9-month follow-up, healing of the mandibular right central incisor was uneventful and no swelling, purulence or pain was revealed in the associated area. Probing pocket depth was favorably stable, and the tooth mobility was decreased to the Miller's Class I. Conclusions: Apical cemental tear associated periapical lesion could be successfully treated with removal of the detached cementum in combination with apical surgery and GTR procedure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.438-440
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• 2010

A lipoma is a benign tumor of matured adipose tissue that usually occurs at the shoulder, back, and abdomen. 13% of lipomas occur in the head and neck area. However, the incidence of lipoma in the parotid gland is very low, approximately 2.5%. A conservational surgical excision is recommended in cases of lipoma of the parotid gland, with only 1-2% of lipomas recurring. We report a case of a lipoma in the parotid gland that was removed by conservational surgical excision. The lesion was exposed by the pre-auricular approach and the tissue was detached. After the parotid gland envelop was exposed, a yellowish mass is observed that was easy to remove due to capsulation. Most authors recommend a surgical excision of the superficial lobe of the parotid gland as the treatment for a lipoma in the parotid gland. However, enucleation only may be a sufficient treatment when a lipoma occurs in the superficial lobe or around the parotid gland. A patidectomy is not needed when a lipoma is located at the superficial lobe of the parotid gland, and a conservational surgical excision is suitable. Therefore, a clinical diagnosis is important for reducing the damage to the facial nerve.

• The Journal of Korean Academy of Prosthodontics
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• v.26 no.1
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• pp.185-196
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• 1988

The purpose of this investigation was to analyze the color of natural teeth by means of the OFC-1001 DP colorimeter which could measure in Adams Coordinate System (L,a,b system). The subjects were the 164 persons (82 men and 82 women) ranged from the teen to the sixtieth who had come to infirmary of dental college, Chosun University. The colors of incisal third, middle third and cervical third of maxillary right incisor, maxillary right canine and maxillary right second premolar were examined after the teeth were cleaned, polished and dried. The data were analyzed statistically by means of SPSS (Statistical Package For the Social Science). The results were as follows. 1. The means of L(lightness), a (red chromaticity), b (yellow chromaticity) of all teeth were measured (Table 2,3,4). 2. The color of teeth was yellowish-gray or bluish-gray. 3. The L value and b value of the cervical third was greater than those of the incisal and middle third. 4. The L value of maxillary 2nd premolar was greater than those of maxillary incisor md maxillay canine. 5. The a & b values of maxillary canine were greater than those of maxillary incisor and maxillary 2nd premolar. 6. The average values of L,a,b of teeth between male and female were not significant. 7. The L values of teeth were decreasing and the b values of teeth were increasing as the age was increased, but there was no corelation between the a values and aging.

• Archives of design research
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• v.17 no.2
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• pp.373-382
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• 2004

The value of Korean ginseng has been known in the world since the 4th century B. C. Red ginseng is hot-steamed, and then dried for the purpose of long-term storing. Through the steaming and drying process, its moisture rate is reduced to 14% and its color becomes citrine or light yellowish brown. Its hardened structure enables long-term storage without any deformation. Especially, Korean red ginseng contains substances that promote micro-physiological activities which are not found in American or Sanchi ginseng. Ginseng is produced in diverse forms for the customer's convenience. In this study, these are classified as sliced, dried, and honeyed ginseng, granulated tea, extract, powder, capsules, tablets, drinks and candy. Package design is one of the most effective method in the marketing fields. However, in this research, we found that red ginseng packages are not variously and properly developed in materials and designs. The research pointed out the problems and discuss ways and means of the package design.

• Development and Reproduction
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• v.16 no.4
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• pp.321-327
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• 2012

Korean bullhead (Pseudobagrus fulvidraco) was collected from the Kum River areas of Kangkyung-eup, Nonsan city, Chungcheongnam-do, Korea, from April to June, 2012 and was fertilized in order to observe egg development and temperature-related cleavage rates and mitotic intervals (${\tau}_0$). The fertilized eggs were separative, demersal and light yellowish with $1.5{\pm}0.06mm$ in diameter, and did not contain oil globules. The first cleavage stages were 90 min, 80 min, 60 min and 50 min at $21^{\circ}C$, $24^{\circ}C$, $27^{\circ}C$ and $30^{\circ}C$, respectively. At higher temperatures, eggs developed faster and underwent further identical development. For Korean bullhead, ${\tau}_0$ were $33.4{\pm}2.08$ min at $21^{\circ}C$, $31.5{\pm}3.06$ min at $24^{\circ}C$, $28.1{\pm}2.11$ min at $27^{\circ}C$ and $26.4{\pm}3.35$ min at $30^{\circ}C$. There were strong negative correlations between the $\tau_0$ and water temperatures at all points studied (Y=-1.13X+58.15, $R^2$=0.98, n=30, where Y is ${\tau}_0$ and X is temperature). The results obtained in this work will be helpful for chromosome manipulation by use of cleavage frequency data and ${\tau}_0$ data in Korean bullhead.

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.548-555
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• 2002

This study was carried out to investigate the quality characteristics of Baiksulgis made of imported rice(Thai and Chinese rice, harvested in 1998) and domestic rice(Chuchung byeo, harvested in 1998 and 1997). Moisture content, color value, yields of reducing sugar by $\beta$-amylase reaction, texture and sensory properties of Baiksulgis were measured. Moisture contents of rice flour and Baiksulgi made of Korean rice harvested in 1997 were highest and those of Thai rice were lowest among the samples. This tends were also seen during storage. Lightness and redness of Baiksulgi made of Thai rice were lowest and yellowness of Baiksulgis made of Korean rice harvested in 1997 and Chinese rice were higher than those made of other rices. Yield of reducing sugar by $\beta$-amylase reaction was highest in Baiksulgi made of Korean rice harvested in 1998 and lowest in Baiksulgi made of Thai rice. And the value decreased less than half of initial value after 24 hour storage. Adhesiveness of Baiksulgi made of Thai rice was zero and cohesiveness, chewiness and gumminess of that were very low. This results showed that Baiksulgi made of Thai rice was lack of chewy texture and this trend was more apparent as the storage time increased. In sensory tests, Baiksulgi made of Chinese rice had most yellowish color and that made of imported rice such as Chinese and Thai rice had more coarse texture than that made of domestic rices. off odor was lowest in Baiksulgi made or Korean rice harvested in 1997 and sweet taste was lowest in that made or Thai rice. Hardness adhesiveness, moistness and chewiness of Baiksulgi made of domestic rices were much higher than those made of impoted rices, and these results showed that Baiksulgi made of domestic rices had acceptable texture. Baiksulgi made of Thai rice showed the lowest acceptability due to lack of above textural characteristics and it was needed to add the material to modify the texture of that.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.537-541
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• 2004

Based on reaction time and substrate molar ratio, structured lipid (SL-corn) was produced at 1:2:2(corn oil/capric acid/CLA) and 4% immobilized lipase from Rhizomucor miehei (RM IM). Reaction was carried out for 24 hr at $55^{\circ}C$ in 1-L stirred-batch reactor. After reaction, 13.3 mol% capric acid and 8.9%, CLA were incorporated into corn oil. Iodine and saponification values of SL-corn were 68 and 202, respectively. Tocopherol content decreased after reaction (about 39%). SL-corn showed more yellowish color than corn oil (p<0.05). Reversed-phase HPLC indicated triacylglycerol species containing capric acid in SL-corn resulted in faster crystallization than that of corn oil.