• Title/Summary/Keyword: mold occurrence

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New Fungal diseases of Economic Resource Plants in Korea (III) (유용 자원식물의 진균성 신병해(III))

  • 신현동
    • Korean Journal Plant Pathology
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    • v.11 no.3
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    • pp.197-209
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    • 1995
  • This paper is a third report about the new fungal diseases of economic resource plants in Korea. It contains short descriptions on symptoms, occurrence conditions, pathogen, and some phytopathological notes for each of 10 fungal plant diseases. They are angular leaf spot of Achyranthes japonica by Cercospora achyranthis causing leaf spot and defoliation in the shade of plants, leaf spot of Armoracia lapathifolia by Cercospora armoraciae causing leaf spot to blight from the rainy season to autumn, hypophyllous mold of Dioscorea tokoro by Distocercospora pachyderma causing leaf spot and yellowing, hypophyllous mold of Artemisia spp.by Mycovellosiella ferruginea causing leaf spot and yellowing, angular leaf spot of Aralia elata by Pseudocercospora araliae causing velvety leaf spot and defoliation, hypophyllous mold of Lycium chinense by Pseudocercospora chengtuensis causing velvety leaf spot and defoliation from the rainy season to autumn, angular leaf spot of Diospyros lotus by Pseudocercospora disospyri-morrisianae causing leaf spot and defoliation from summer to autumn, brown leaf spot of Impatiens textori by Pseudocercospora nojimae causing leaf spot to blight from the rainy season, leaf spot of Cephalonoplos segetum by Ramularia cirsii causing leaf spot to blight throughout the growing season, and white mold of Leonurus sibiricus by Ramularia leonuri causing leaf spot to blight mostly in autumn.

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Study on extending the Die life of the mold in manufacturing wire cut electric discharge machined punches and die plates (와이어 컷 방전 가공한 펀치와 다이플레이트 제작에서의 수명연장에 관한 연구)

  • Kim Sei-Hwan;Chio Kye-Kwang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.545-549
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    • 2006
  • W-EDM is generally used to manufacture punches and die plates from among press mold parts. Before W-EDM was used, however, punches and die plates manufactured via mechanical processing were used to manufacture products, with the die life of the mold expiring after 2,000,000~2,300,000 products have been manufactured. When the mold manufactured through W-EDM was used, however, its service life expired only after 700,000~800,000 products have been manufactured. Since this was attributed to the deformed layer formed after using W-EDM, the surfaces before and after W-EDM was used were scanned using SEM to verify the occurrence of such layer. This study sought to come up with a method of eliminating such phenomenon.

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Occurrence of Blue Mold on Tomato Caused by Penicillium oxalicum in Korea

  • Kwon, Jin-Hyeuk;Shen, Shun-Shan;Jee, Hyeong-Jin
    • The Plant Pathology Journal
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    • v.24 no.1
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    • pp.87-89
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    • 2008
  • A blue mold on tomato fruit caused by Penicillium oxalicum occurred sporadically in a greenhouse at Gyeongsangnam-do Agricultural Research and Extension Services. Infection usually occurred through wounds or cracks on the fruits. Symptoms began with water soaking lesions, then became watery and softened eventually. Colony of the causal fungus was white at the early growing stage, turned green on Czapek yeast extract agar and malt extract agar. Conidia were ellipsoidal in shape and $2-6{\times}2-4{\mu}m$ in size. Stipes were septate, smooth, thin walled, and $90-280{\times}3-4{\mu}m$ in size. Penicilli were mostly biverticillate. Ramuli were 1-3 groups, smooth, and $10-16{\times}2-3{\mu}m$ in size. Rami were 1-2 groups and $6-30{\times}2-4{\mu}m$ in size. Metulae were 2-3(5) verticils, smooth, and $12-20{\times}3-4{\mu}m$ in size. Phialides were 5-7 verticilate, ampulliform to cylindroidal, smooth, and $8-12{\times}2-3{\mu}m$ in size. Optimum temperature for growth was about $25^{\circ}C$. Pathogenicity of the fungus was proved on tomato fruit according to Koch's postulation. On the basis of mycological and pathological characteristics, the fungus was identified as P. oxalicum Currie & Thom. This is the first report of the blue mold on tomato fruit caused by P. oxalicum in Korea.

A Study on the cracks ways minimizing at circular forming (원형포밍 성형 시 크랙 발생 최소화 방안에 관한 연구)

  • Son, Jong-Min;Kim, Sei-Whan;Lee, Chun-Kyu
    • Design & Manufacturing
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    • v.10 no.3
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    • pp.20-24
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    • 2016
  • Foaming is a step of forming by the ratio of the internal combustion chamber in a state where the in flow of the material is suppressed, if the diameter is small and a high to a crack generated on the molding is not possible. The present study, we studied using as part experiments for forming the circular shape of the forming height of 10 mm without the occurrence of cracks, results preformed primary, the need to set the height of the forming than the height of the product, preformed secondary. It was able to increase the height of the molded product with less than the height of the next step to be carried out compression processing to create a small comer of the desired shape. In addition, it was found that on a great influence on the quality of the final quality on the final molding of the primary preformed, secondary.

Effects of Rice Powder Particle Size in Baked Rice Breads (쌀가루의 입도에 따른 쌀 식빵의 품질 특성)

  • Park, Mi-Kyung;Lee, Kwang-Suck;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.3
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    • pp.397-404
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    • 2008
  • The purpose of this study was to help promote the consumption of rice by substituting rice powder for wheat flour in bread preparation and examining the effect of rice powder particle size in baked rice bread samples. Several experiments were carried to analyze and compare the quality characteristics of prepared samples of wheat flour and rice powder breads. The loaf volume index of the wheat flour bread was 6.34, and the indices of the rice powder bread samples, which were made from powder milled through 20, 35, and 45 mesh (S1, S2 and S3), were 5.37, 5.56, and 5.85, respectively. These data indicated that the loaf volume index of the rice powder bread was lower than that of the wheat flour bread, but the volume of the rice powder bread increased as the particle size of the rice powder became finer. According to texture analysis results using a rheometer, the hardness value of the wheat flour bread was $1.34{\times}10^3\;g/cm^2$, and values of S1, S2, and S3 were $1.74{\times}10^3\;g/cm^2$, $1.57{\times}10^3\;g/cm^2$, and $1.47{\times}10^3\;g/cm^2$, respectively. Therefore, S3, which was made from the finest powder among the rice powder samples, showed the lowest level of hardness. No significant differences were observed for springiness, cohesiveness, and gumminess among the bread samples. However, the wheat flour and rice powder breads had significant differences for bread crumb color. The L-value of S3(76.20) was similar to that of the wheat flour bread(77.22). but the L-values of S1(70.30) and S2(71.21) were lower than that of the wheat flour bread. In terms of redness and yellowness, the values of the rice powder breads were significantly different from those of the wheat flour bread. In terms of overall preference, the sensory evaluation results indicated that S3 was significantly the more preferred and the wheat flour bread was the least preferred among the bread samples. This study also investigated texture changes and mold occurrence in bread samples stored at $25^{\circ}C$ for 5 days. From the 3rd day of storage, bread texture became harder in all samples however, S3 showed the least level of change among the rice powder breads. The occurrence of mold began to increase abruptly from the 4th day of storage, and S2 and S3 showed mold numbers that were 2-fold greater than those of S1 and the wheat flour bread.

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Occurrence of Gray Mold on Blueberry Trees Caused by Botrytis cinerea in Korea (Botrytis cinerea에 의한 블루베리 잿빛곰팡이병의 한국 내 발생)

  • Hong, Sung-Kee;Choi, Hyo-Won;Lee, Young-Kee;Lee, Sang-Yeob;Kim, Wan-Gyu
    • The Korean Journal of Mycology
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    • v.39 no.3
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    • pp.213-216
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    • 2011
  • Gray mold symptoms were frequently observed on green twigs, blossoms, leaves, and fruits of blueberry trees grown in greenhouses in Cheongyang, Dangjin, Daejeon, and Jeju during disease survey in eight locations of Korea from 2007 to 2010. The disease symptoms were not observed in the fields of the other locations investigated. The disease incidence ranged 1~30% in the greenhouses investigated. A total of 27 single spore isolates of Botrytis species were obtained from the gray mold symptoms, and all the isolates were identified as Botrytis cinerea based on their morphological and cultural characteristics. Four isolates of the fungus were tested for pathogenicity to leaves of four varieties of blueberry trees by artificial inoculation with conidial suspensions. All the tested isolates caused gray mold symptoms on the leaves, which were similar to those observed in the greenhouses. This is the first report that B. cinerea causes gray mold of blueberry trees grown in greenhouses in Korea.

Analysis of the Damage Patterns and Metal Structure of 3 Phase Mold Transformers to which Interlayer Short-circuits have Occurred (층간 단락된 3상 몰드변압기의 소손 패턴 및 금속 조직 해석)

  • Choi, Chung-Seog
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.86-91
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    • 2010
  • The purpose of this study is to analyze the damage patterns and metal structure of 3 phase mold transformers collected from places where accidents have occurred. Compared to an oil-immersed transformer, a mold transformer has the advantage of requiring a smaller installation area and can be kept clean, while its disadvantages include the fact that abnormal symptoms of an accident are difficult to discover and its repair is impossible. The capacity of the mold transformers collected from places where accidents have occurred was 200kVA with primary voltages being F23,900V, R22,900V, 21,900V, 20,900V, 19,900V, etc., as well as secondary voltages being 380V, 220V, etc. It was found from the analysis on the diffusion of combustion in the damaged mold transformers that fire occurred first inside the U-phase primary winding and that carbonization and heat were diffused to V-phase and W-phase in V-pattern. In addition, from the analysis on the cross-sectional structure of the metal of the melted high voltage winding using a metallurgical microscope, it was found that the boundary surface, voids, and columnar structure were formed when an interlayer short-circuit had occurred Therefore, even though it is not possible to find the cause for the occurrence of an interlayer short-circuit at the inner side of the primary winding, it is thought that, due to the thermal energy generated when the short-circuit occurred, the heat source was diffused to the upper side and outside, causing a secondary accident.

Effect of film liner packaging with chlorine dioxide on the storage quality of containergrown or bare-root seedlings at cold or frozen temperatures in sawtooth oak and Japanese larch

  • Yu-Rim, Kim;Min-Seok, Cho;Byung-Bae, Park;Jong-Pil, Chun
    • Korean Journal of Agricultural Science
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    • v.48 no.4
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    • pp.753-760
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    • 2021
  • This study was carried out to discover suitable packaging methods during the cold or frozen storage of sawtooth oak and Japanese larch seedlings, which are major afforestation tree species in Korea. The weight loss rate of sawtooth oak was lower under frozen storage at -2℃ (maximum, 33.7%) than under cold storage at 2℃ (maximum, 61.0%). A film liner treatment inside the packaging box effectively suppressed the increase in the weight loss rate. For the sawtooth oak containerized seedlings, when stored at -2℃, the rate of weight loss was 17.9 to 25.4% in the untreated group and less than 1% in the film liner treatment group. Similar results were observed with Japanese larch. After two months of freezing at -2℃, both species maintained a low index of 1.0 - 1.1 with regard to the degree of shoot desiccation of containerized seedlings, and there was no significant difference between the treatments. On the other hand, the chlorine dioxide treatment could more effectively reduce the occurrence of mold and shoot desiccation than a PE single treatment in bare-root seedlings. According to these results, it was concluded that frozen storage is generally suitable as a means of long-term storage compared to cold storage of sawtooth oak and Japanese larch. A chlorine dioxide treatment at 20 ppm was effective for maintaining seedling quality levels during storage, demonstrating the good effect of suppressing the occurrence of shoot desiccation and the occurrence of mold.