• Mycobiology
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• v.40 no.4
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• pp.268-271
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• 2012

In June 2012, leaf spot and stem rot were observed on Wilford Swallowwort plants grown in Cheonan, Korea. Three fungal isolates obtained from the diseased leaves and stems were identified as Stemphylium lycopersici, based on morphological, cultural, and molecular characteristics and pathogenicity. This is the first report of leaf spot and stem rot on Wilford Swallowwort caused by S. lycopersici.

• Mycobiology
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• v.40 no.4
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• pp.265-267
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• 2012

Sleeping blight was observed on soybean plants grown in Yanggu, Suwon and Geumsan from 2005 to 2011. Symptoms developed on stems and pods of affected soybean plants. Five fungal isolates were obtained from the diseased plants and identified as Septogloeum sojae based on their morphological, cultural and molecular characteristics. Pathogenicity of the fungus was confirmed on soybean plants by artificial inoculation. This is the first report of S. sojae causing sleeping blight in soybean plants in Korea.

• Mycobiology
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• v.38 no.4
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• pp.339-342
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• 2010

Basal stem rot symptoms were found on blueberry seedlings imported from the United States of America in 2008. The fungus obtained from the diseased seedlings was identified as Calonectria colhounii based on morphological and molecular characteristics. The consignments of the blueberry seedlings infected with C. colhounii were destroyed to prevent introduction of the fungus to Korea.

• The Korean Journal of Mycology
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• v.45 no.4
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• pp.377-380
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• 2017

In 2015, a new leaf spot disease was observed on strawberry seedlings in Wanju, Korea. Tanned brown spots appeared on the leaves of the infected plants, and often coalesced to form larger necrotic areas, resulting in the death of foliage. An isolate was obtained in pure culture. On the basis of morphological characteristics and molecular analysis of internal transcribed spacer rDNA sequence, the causal agent was identified as Pilidium concavum. Pathogenicity tests revealed the isolate was pathogenic to the leaves and fruits of strawberry. To the best of our knowledge, this is the first report of P. concavum causing tan-brown leaf spot on strawberry in Korea.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.95-96
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• 2006

Surface modification of clay minerals has become increasingly important for improving the practical applications of clays such as polymeric nanocomposites. We used the copolymer as modifiers having phenyl components, and successfully developed a route for the preparation of amine functionalized polymer based on oligostyrene and its block copolymers. The oligo(St-co-VBC)s with controlled molecular weight were synthesized via nitroxide mediated polymerization method. We also successfully prepared organophilic layered silicates whose surface is covered with styrenic copolymers. Through the analysis of chemical structure and morphology, we concluded that copolymers were very effective organic modifiers to change the surface characteristics of layered silicates.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.2
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• pp.8-17
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• 2012

Three kinds of cationic acrylamide copolymer with different branch degree were prepared controlling the dosage of N, N'-methylenebisacrylamide. The physical characteristics of the branch-degree-modified copolymers were analyzed by intrinsic viscosity and charge density. The branch degree measurements were investigated by applying the colloidal titration phenomena using a spectrophotometer and comparison with the cationic regain measurement method. The results showed that the absorbance behaviors of spectrophotometer were distinctively different with the branch degree of copolymers. Also, the branch degree determinations and molecular structure estimations of the copolymers were numerically measured by applying the titration phenomena using a spectrophotometer. Finally, three kinds of branch-degree-modified copolymers were applied to flocculation test using arbocel micro pulp for the determination of flocculation behavior by different morphology of cationic acrylamide copolymers.

• Animal Systematics, Evolution and Diversity
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• v.30 no.1
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• pp.26-32
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• 2014

Cleantioides planicauda (Benedict, 1899) has previously been recorded in China and Japan. In the present study, to our knowledge, we report for the first time the occurrence of this species in South Korea. Here, we provide detailed descriptions and illustrations of the diagnostic characteristics of C. planicauda. Further, for the first time, we determined the partial sequence of mitochondrial cytochrome c oxidase subunit 1 (CO1) gene of C. planicauda for molecular characteristic. Additionally, we provide a key to the Korean species and distribution of the genus Cleantioides. As a result of this study, four species of the genus Cleantioides, including C. planicauda, have now been recorded in South Korea.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.394-399
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• 1986

From the lysates of the 7 selected strains of Pseulomonas utilizing 2-methyl-4-chlorophenoxyactate as a sole source of carbon and energy, several MCPA plasmids, which encodes genes for the degradation of 2-methyl-4-chlorophenoxyacetate, were isolated, and measured their molecular weight as well as genetic characters such as resistance to antibiotics and degradative ability of other chlorinated herbicides. Transmissibility of the MCPA plasmids, pKU1, pKU15, and pKU17 was tested by conjugation or transformation and the restriction pattern of pKU15 for Pvu II, Hind III, EcoR I, Xho I, Bgl II, and Ava II was analyzed.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.906-909
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• 2005

In this study, the dynamic flying characteristics of the worn head sliders are investigated theoretically due to the change in head geometry caused by head and disk contact. The film shapes can be approximated as taper- truncated cycloidal-flat film. Two-dimensional time dependent modified Reynolds equation included molecular slip effect are formulated with neglected the roughness effect. The motion of head slider was assumed to have two degree of freedom in this work. Finite difference approximation with Newton Raphson iterative technique and the fourth order Runge-Kutta method were implemented to obtain the transient response of the slider head with various change in head geometry numerically and compared with the transient response of the IBM3380 type head slider. The simulation results show the film shape has affects significantly on the static and dynamic characteristic of slider head in magnetic storage systems.

• Journal of Environmental Science International
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• v.13 no.6
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• pp.543-549
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• 2004

Polycyclic aromatic hydrocarbons(PAHs) in sediments of Kwangyang bay on Korea, have been investigated by gas chromatography-mass spectrometery (GC/MS). The average content of total PAHs in all samples was 2,211ppb, and the range was from 36 to 22,699ppb. The higher concentrations were found in sediment sampled near Kwangyang iron processing plant, Taeindo. The resulting distributions of PAHs according to the number of aromatic ring and molecular ratios of specific aromatic compounds (phenanthrene, anthracene, fluoranthene and pyrene) have been discussed in terms of sample location, origin of the organic matter. Four, five and six rings of PAHs were mainly found near to Kwangyang iron processing plant, and three and four rings near to Yeosu chemical kombinat This result typically indicated the local characteristics, depending on the origin of PAHs.