• Journal of the Korean Magnetics Society
• /
• v.10 no.5
• /
• pp.203-209
• /
• 2000

Top synthetic spin valves with structure Ta/NiFe/CoFe/Cu/CoFe(P 1)/Ru/CoFe(P2)/FeMn/Ta on Si (100) substrate with natural oxide were prepared by dc magnetron sputtering system. We have changed only the thickness in free layers and the thickness difference (Pl-P2) in two ferromagnetic layers separated by Ru, and investigated the effect of magnetic film thickness on interlayer coupling field in spin valve with synthetic antiferromagnet. According to the decrease of free layer thickness, interlayer coupling field was increased due to the magnetostatic coupling(orange peel coupling). In case of t$\_$P1/>t$\^$P2/, interlayer coupling field agreed well with the modified Neel model suggested in conventional spin valve structures by Kools et al. However, in case of t$\_$P1/>t$\^$P2/, it was found that the interlayer coupling field was not explained by the Modified Neel Model and was confirmed the necessity of further remodeling. The dependence of Cu thickness on the interlayer coupling field was investigated and 10 Oe of interlayer coupling field was obtained when the Cu thickness is 32 $\AA$.

• Korean Journal of Food Science and Technology
• /
• v.27 no.3
• /
• pp.342-347
• /
• 1995

Experiments were conducted to investigate the effects of storage temperature and blanching treatment on the storage stability in order to extend the shelf life of Citrus junos. Chilling injury of Citrus junos was not observed at the temperature range of $0^{\circ}C{\sim}5^{\circ}C$. Respiration rate of Citrus junos classified into climacteric characteristics as storage time goes by increase of respiration rate. The $Q_{10}$ value of Citrus junos during storage appeared to have a narrow range of $2.3{\sim}2.4$ The decaying rate increased drastically at $20^{\circ}C$ ranging from 71.4% to 86.5%. It was not much influenced by the pretreatments but by the storage temperature. There was no difference in weight loss between the control and blanching treatment. The weight loss of Citrus junos at $20^{\circ}C$ appeared to be high during the 12 weeks period, and consequently the overall quality of Citrus junos was rapidly decreased. The ratio of brix to acid showed a slow increase for Citrus junos stored at $3^{\circ}C.\;At\;20^{\circ}C$, however, it increased rapidly and then decreased. This phenomenon was mainly due to the relatively high increase of brix, compared to the increase in acid content. Development of browning color in Citrus junos was mainly associated with Citrus junos peel, rather than with Citrus junos pulp.

• Korean Journal of Food Science and Technology
• /
• v.26 no.5
• /
• pp.552-556
• /
• 1994

It was aimed to study the chemical characteristics and volatile compounds of juices extracted by press (PE) and centrifugal extractors (CE). Citrons cut up cross direction were used as samples in PE. Proportion ratio of peel, flesh, and seed of citron were 43.9, 39.4 and 16.7%, respectively. Yield of juice increased with weight to 120g of citron fruit. pH, brix, pulp, oily materials, amino nitrogen and yield of juice extracted by CE were higher than those of juice by PE. Acidity and transmittance of juice extracted by PE were higher than those of juice by CE. Free sugars of citron juice were consisted of fructose, glucose and sucrose. Free sugar contents of juice by CE were twice as much as those of PE. Major volatile compounds of total steam distillation matters of citron juice extracted by PE were dl-limonene, ${\gamma}-terpinene\;{\beta}-farnesene$, sabinene, linalool, ${\beta}-myrcene$ and terpinolene, while those by CE were dl-limonene, ${\gamma}-terpinene$, sabinene, ${\beta}-myrcene,\;{\alpha}-pinene$, linalool and terpinolene. dl-Limonene and ${\gamma}-terpinene$ consisted of $73{\sim}83%$ of total volatile compounds. dl-Limonene of juice by CE increased about 6% that of juice by PE. ${\beta}-Farnesene$ were observed trace in juice by CE but presented in 7% in juice by PE. The results would suggested that chemical characteristics and volatile compounds of citron juice seemed to depend on extraction methods.

• 한국문화재보존과학회:학술대회논문집
• /
• 2004.10a
• /
• pp.15-24
• /
• 2004

The Seokgatap pagoda composed of mainly alkali granite and other minor pink-feldspar granite, fine-grained granite, granodiorite, diorite, gabbro, and tuff. Despite the small loss and damage derived from joints, its peel-off and exfoliation are serious enough to cause the heavy deterioration on the stone surface. The chemical and petrological weathering has partly replaced the original rock-forming minerals with clay minerals and iron oxyhydroxides. Based on the petrogenesis, rock materials of the pagoda is very similar to rocks of Dabotap pagoda and the Namsan granite in the Gyeongju. The central fart of the pagoda has sunken highly, which caused all the corners to split and the structural transformation to become worse. The reverse V-shaped gaps between the materials have broken stones filled in a coarse way. The iron plates inserted between the upper flat stone laid on other stones and tile pagoda body in the north and east side has been exposed in the air and corroded, discoloring of the adjacent stones. The overall diagnosis of the Seokgatap pagoda is the deteriorated functions of the stone materials, which calls for a long-term monitoring and plans to reinforce the stone surfaces. But the main body including the pagoda roof stone needs washing on a regular basis, and the many different cracks should be fixed with glue by using the fillers or hardeners designed for stone cultural properties after removing the cement mortar. In case of the replacement of the stone materials with new stones, it's necessary to examine the pagoda for the center of gravity and support intensity of the materials. The structural stability of the pagoda can be attained by taking a reinforce measure in geotechnical engineering and making a drainage. The ground humidity, which has aggravated weathering and structural instability, should be resolved by setting up a humidity reduction facility. The contamination of lichens and bryophyte around the pagoda and on the surface is serious. Thus biochemical treatments should be given too in order to prevent further biological damages and remove the vegetation growing on the discontinuous planes.

• 한국문화재보존과학회:학술대회논문집
• /
• 2004.10a
• /
• pp.92-100
• /
• 2004

The host rocks of brick-shaped stone pagoda in the Bunhwangsa temple are lots of kinds andesitic rocks, which has gone through mechanical and chemical weathering. As the overall observation, the pagoda is serious damages by air pollutants, and the northeast parts show the much advanced state of turning white, while the southeast parts are heavily cracked in the materials. The rocks of brick-shaped pagoda body are in a relatively stable condition of weathering and damage except for the abrasion and cracks of the corners. The rocks of the pagoda roof suffer from more symptoms including multiple peel-offs, exfoliation, cracks forming round lines, and falling off stone pieces. The pagoda roof rocks are dominated by the thriving leafy lichens and mosses, especially, there are higher plants (selaginella involvens, dandelions) taking root actively between the brick stones and content mortar. There are even light gray precipitates like stalactites between the rocks of the body, In particular, the 1st and 2nd floor in the east side and the body parts in the north side are the most serious. Their major minerals are calcite, gypsum and clay minerals. The rocks of the stylobate and the tabernacle in all the four directions are composed mainly of granitic rocks. The materials consisting of the tabernacles show the severe splits and distortion, which causes the structural instability. The stylobate rocks are heavily contaminated by some weeds with the often marks of inorganic contamination by secondary hydroxides. The central part of the east stylobate has been sinking, while that of the 1st floor west stylobate is protruded nesting a line of cracks. Accordingly, the inside of the tabernacle is always humid with the constant introduction of rainwater. The stone lion standing in the southeast and northeast side are alkali granite, while that in the southwest and northwest lithic tuff. Each of the stone lion also coated with various colored lichens, mosses, algae, bacteria and bryophyte. The external materials of the pagoda have deteriorated the functions of the rocks and made the loss, falling off, and biological contamination even worse due to the surface weathering. Thus it's urgent to come up with scientific restoration and conservation measures through clinical tests.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.2
• /
• pp.76-82
• /
• 2010

This study was carried out to compare and analyze control methods of the sunburn occurrence that affected 'Fuji'/M.9 planting systems in Korea from 2001 to 2003. It is very important to control temperature of the surface of fruits, because sunburn may occur when the temperature of fruit surfaces reaches $40^{\circ}C{\sim}45^{\circ}C$ due to high air temperature and sunlight during growing periods. As control methods of the sunburn occurrence, white coating materials such as $CaCO_3$ or kaolin were applied four times at two-week intervals from late June, and microspraying of water was conducted when air temperature was over $31^{\circ}C$ from late July to mid-August. Both methods were effective for preventing the sunburn occurrence and improving fruit quality by decreasing peel's temperature of fruits and increasing photosynthesis.

• Korean Journal of Food Science and Technology
• /
• v.33 no.1
• /
• pp.12-18
• /
• 2001

The water-soluble extracts of plants used as tea materials were investigated for their antioxidant activities and active components(total phenolics, ascorbate and selenium). Antioxidant activities of the plant extracts were determined by measuring the changes in both peroxide values(POV method) during storage(36 day, $55^{\circ}C$) and conductivity of soybean oil at $110^{\circ}C$(Rancimat method). Soybean oil without any additive was used as a control. Soybean oil treated with 0.02% BHT was used as a positive control. The test samples were prepared by mixing the plant extracts with soybean oil in 0.02% concentration by weight. The water-soluble extracts of lycii fructus(23 d), oolong tea(23 d), orange peel(23 d), citron(22 d), and apricot(22 d) showed longer induction periods, compared to control(21 d) and BHT(21 d) by POV method. Also water-soluble extracts of oolong tea(12 h), instant coffee(11 h), citron(10 h), cinnamomi cortex(10 h), schizandrae fructus(10 h), lycii fructus(10 h) and apricot(10 h) demonstrated longer induction periods, compared to control(8 h) and BHT(8 h) by Rancimat method. The contents of total phenolic compounds were observed to be high in water-soluble extracts of oolong tea, green tea, black tea, coffee, cinnamomi cortex, and cassiae semen. Ascorbate contents were found to be high in coffee, eucommiae cortex, black tea, ganoderma, cinnamomi cortex, persimmon leaf, chicory, green tea and oolong tea extracts. The selenium contents were not detected in all the extracts. The antioxidative effects of some plant extacts were seemed to be the combined effects of various antioxidant components such as phenolics and ascorbate.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.4
• /
• pp.635-640
• /
• 2001

These studies were carried out to develop sausage using extracts from waste resources. The changes of pH and moisture contents were tended to be a similar to control, respectively ranged in pH 6.0~6.4 and 62~60% in moisture content. However, the water holding capacity of sausage added with chitosan and sesamol gradually were tended to be a little high, compared to control. The treatments using natural resource by-product revealed a low TBARS value, compared to control. This means that sausage added with natural by-product seem to be extend its shelf-life during storage. At the same time, the TBARS values were very similar to sausage added with 0.5% potassium sorbate. The residual nitrite contents of sausage added with natural resource by-product were tended to be a little lower than that of control. As storage time goes by, the nitrite contents of sausage product gradually were a little more decreased during storage at 3$0^{\circ}C$ than those of storage at 1$0^{\circ}C$. The lightness of sausage color gradually were a little more decreased during storage at 3$0^{\circ}C$ than those of storage at 1$0^{\circ}C$. The redness of sausage added with chitosan were a little highter, compared to control Sensory test suggested that the changes of sausage color, flavor, texture and taste were tended to be decreased gradually. In conclusion, sausage added with natural resource by-product was effective on the basis of the reduction in residual nitrite content and lipid oxidation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.1
• /
• pp.1-7
• /
• 2003

Radiation induced markers were investigated for the detection of irradiated oranges imported from America. In the DNA comet assay, the non-irradiated and irradiated samples showed the comets with long tails in both seed and flesh. Though this tendency was maintained for 6 weeks, identification of non-irradiated or irradiated samples was impossible. In the thermoluminescence (TL) measurement, the non-irradiated samples revealed a glow curve with low intensity at about 28$0^{\circ}C$, while the irradiated samples showed with higher intensity at around 18$0^{\circ}C$. There were no remarkable changes in detection properties for 6 weeks after irradiation. The TL ratio of area for TL$_1$ glow curve to TL$_2$ was below 0.1 for the non-irradiated samples and 0.5 or more for the irradiated ones during storage. In the electron spin resonance (RSR) measurement, irradiated oranges showed an unspecific central signal in all parts (seed, flesh and peel), so the detection for radiation treatment of oranges was impossible. Based on the results, DNA comet assay and ESR were not useful for the detection, but TL was appropriate to search radiation induced markers of oranges during storage period. The detectable period during storage is confirmed by sensory evaluation.

• Journal of Haehwa Medicine
• /
• v.13 no.2
• /
• pp.187-196
• /
• 2004

Now many sustitution and false articles is used in korea instead of shanyao. To use shanyao correctly, we will make a quilitative certificational plan of shanyao to investigate all of lieraturea, records and documents. And we could reach conclusions as folloews. 1) Source About a source of shanyao, though korea and china has a each other source, we think there is no problem in use of both. 2) Process In our country producing shanyao as medical use is a 'duanma', we can divide into peeling and non-peeling, drying at bulks and at briquets, steaming shanyao and fresh shanyao. Regardless of existence for peeling and steaming, a distributing shanyao is received a proper judgment. Like this result was expressed by insufficiency of standards about medical components or indicating components. We detected a reminding S02 more than 10 ppm. And this expresses that there ia a problum at a drying method. To suggest proper processing methods, a standard of quility will have to be made which the existence of peeling, difference of quility between 'changma' and 'duanma', drying method and exudation test with cutted thickness are adaptable. Besides, 'maoshanyao' and 'guangshanyao' of china is processed by various methods which decrease a medical effect such as too much soaking shanyao in water, steaming with a sulfur, too much peeling, So we must process shanyao like the next methods. (1) When harvesting, dig deeply not to cut off roots. (2) Not to peel, wash shanyao in a washing machine. (3) Dry to 50-60% degree at sunny place or drying machine. (4) To be easy for drying and exudation, cut off a thick piece with 5 mm (5) Dry perfectly at ding machine. 3) Quality3) Quality (1) Functional standards It is not Proper that 'guangshanyao' is used in china because it has a problem with quility on process of working, If they did not soak shanyao in water or heat with steam, it is the real situation that they cannot cutt off shanyao evenly. In conclusion, shanyao must be heavy, powdery with a perfectly non-peeling surface, section surface is yellow-white color, unequal and has no holes. (2) Physicochemical standards It is the real situation that we can not distinguish into quility of shanyao with established test because various workings which decrease medical effects is used. Therefore we suggest a testing standard of S02 which is used in bleaching. And testing standards relatived with decrease of medical effects must be established at once. It must that Dry on loss is less than 14.0%, content of ash is less than 6.0%. Content of acid-nonsoluble ash is less than 0.5%. Contens of heavy metal has to detect less than 30 ppm and there is no reminding agricultural medince.