• Research in Plant Disease
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• v.26 no.1
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• pp.53-56
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• 2020

Red spots symptoms were observed on the leaves of Rumex japonicus Houtt. in Goesan, Korea, in May 2019. Diseased leaf showing red spot and white-colored sori were found behind of diseased leaves. Aeciospores were confirmed and observed using a stereomicroscope, light microscope, and scanning electron microscope. They were globose or ovoid and measured 19.0-24.4×19.0-24.5 ㎛, with verrucae ornamentation. For the phylogenetic analysis, partial of large subunit rDNA region and cytochrome c oxidase subunit III were sequenced. As a result, the isolated fungus species showed high similarities with Puccinia prizeliana. Based on the previous report, morphological characters, phylogenetic analysis, it was confirmed as Puccinia phragmitis which have not been reported in Korea, and we firstly report this fungal agent on R. japonicus as P. phragmitis in Korea.

• Advances in environmental research
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• v.1 no.1
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• pp.1-14
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• 2012

We demonstrated that reductive degradation of 2,4,6-Trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (Royal Demolition Explosive, RDX) can be enhanced by bio-reduced iron-bearing soil minerals (IBSMs) using Shewanella putrefaciens CN32 (CN32). The degradation kinetic rate constant of TNT by bio-reduced magnetite was the highest (0.0039 $h^{-1}$), followed by green rust (0.0022 $h^{-1}$), goethite (0.0017 $h^{-1}$), lepidocrocite (0.0016 $h^{-1}$), and hematite (0.0006 $h^{-1}$). The highest rate constant was obtained by bio-reduced lepidocrocite (0.1811 $h^{-1}$) during RDX degradation, followed by magnetite (0.1700 $h^{-1}$), green rust (0.0757 $h^{-1}$), hematite (0.0495 $h^{-1}$), and goethite (0.0394 $h^{-1}$). Significant increase of Fe(II) was observed during the reductive degradation of TNT and RDX by bio-reduced IBSMs. X-ray diffraction and electron microscope analyses were conducted for identification of degradation mechanism of TNT and RDX in this study. 4-amino-dinitrotoluene were detected as products during TNT degradation, while Hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, Hexahydro-1,3-dinitroso-5-nitro-1,3,5triazine, and Hexahydro-1,3,5-trinitroso-1,3,5-triazine were observed during RDX degradation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.4
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• pp.309-314
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• 2004

0.5mm thick steel is used to manufacture nail files. The first process is blanking and the second process is making about 300 holes of 0.8-l.0mm in diameter. This process depends mainly on etching which takes 33% of manufacturing cost and it can make manufacturing cost rise. The residual etching reagent is not environmentally friendly and the steel material is apt to rust as well. To solve these problems, researches on the following subjects are performed: proper material to prevent from rusting and strip layout strategies in stamping to replace etching process with press process which makes use of die. And new quill type punch is developed to replace the regular standard punch, one of the die parts, which frequently get broken while working. And these researches and developments lead to develop a progressive perforating die.

• FLOWER RESEARCH JOURNAL
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• v.18 no.4
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• pp.303-307
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• 2010

A new spray chrysanthemum cultivar 'Snow Bowl' was released by National Institute of Horticultural & Herbal Science(NIHHS), Rural Development Administration (RDA), in 2008. The cross was made in 2005 between '03B1-230', breeding lines of NIHHS and 'Sei-Alps'. Trials were conducted from 2006 to 2008 for the evaluation and selection of this cultivar, including shading cultures in summer and retarding cultures in spring. The natural flowering time of 'Snow Bowl' is late October, but year-round flowering is possible by photo-periodic control. It has single type flowers with white petals. The growth of plant is very vigorous and it is resistant to white rust. The diameter of flower is 6.3cm. Number of flowers per stem and petals per flower are 12 and 31, respectively. Days to flowering under the short day treatment is about 59 and its vase life is 24.1 days in autumn season. 'Snow Bowl' was applied as No. 2009-179 on February 18, 2009 for variety protection and the plant variety protection rights have been registered as No. 3239 on August 3, 2010 at the Korea Seed and Variety Service.

• Journal of Soil and Groundwater Environment
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• v.25 no.2_spc
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• pp.16-27
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• 2020

Nitrate contamination has received much attention at local as well as regional scales. The domestic situation is not out of exception, and it has been reported to be very serious, particularly within agricultural areas as a result of excessive usage of nitrogen fertilizers. Meanwhile, nitrate can be naturally attenuated by denitrification in subsurface environments. The denitrification occurs through biotic (biological) and abiotic processes, and numerous previous studies preferentially focused the former. However, abiotic denitrification seems to be significant in specific environments. For this reason, this study reviewed the previous studies that focused on abiotic denitrification processes. Firstly, the current status of nitrate contamination in global and domestic scales is presented, and then the effect of geological media on denitrification is discussed while emphasizing the significance of abiotic processes. Finally, the implications of the literature review are presented, along with future research directions that warrant further investigations. The results of previous studies demonstrated that several geological agents could play a vital role in reducing nitrate. Iron-containing minerals such as pyrite, green rust, magnetite, and dissolved ferrous ion are known to be powerful electron donors triggering denitrification. In particular, it was proven that the rate of denitrification by green rust was comparative to that of biological denitrification. The results indicate that abiotic denitrification should be taken into account for more accurate evaluation of denitrification in subsurface environments.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.606-610
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• 2010

A new cultivars Dendranthema grandiflourm 'Dream Moon' was developed at Gyeonggi-do Agricultural Research and Extension Services (GARES), Korea in 2008. The cultivar 'Dream Moon' was derived from a cross between 'Patra', a spray cultivar with yellow single type, and 'Sei-rosa', a spray cultivar with pink single type in 2005. The cultivar has single type flowers with pink petals. Trial evaluation was conducted from 2006 to 2008 for a shading cultivation in summer and a retarding cultivation in spring. The flowering time of 'Dream Moon' is late October, and year-round flowering is possible by shade or light treatment. The diameter of flower is 56.0 mm. Numbers of flowers per stem and petals per flower are 16.4 and 24.6, respectively. After investing of specific characters from 2006 to 2008, it was finally selected and named 'Dream Moon'. It has resistance to white rust and the vase life is about 20.7days in autumn season.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.476-483
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• 2023

The present study concerns modelling the structural behaviour for concrete structure into the crack initiation at corrosion of steels. The degradation source included the axial load and steel corrosion. A development of the rust formed on the steel surface was considered with the interfacial gap between steel and concrete. As a result, the tensile damage could occur on the surface of concrete into the cracking with no steel corrosion, which could be further developed by the increasing rust formation, while the cracking at the steel-concrete interface was mainly attributed to the compressive deformation, being restricted within the interfacial zone.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.2071-2075
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• 2007

Fourteen Bacillus thuringiensis isolates having both insecticidal activity and in vitro antifungal activity were selected and tested for in vivo antifungal activity against tomato late blight, wheat leaf rust, tomato gray mold, and barley powdery mildew in growth chambers. All the isolates represented more than 70% disease control efficacy against at least one of four plant diseases. Specifically, 12 isolates exhibited strong control activity against barley powdery mildew. Under glasshouse conditions, four (50-02, 52-08, 52-16, and 52-18) of the isolates also displayed potent control efficacy against cucumber powdery mildew. To our knowledge, this is the first report of B. thuringiensis isolates that have disease control efficacy against powdery mildew of barley and cucumber as well as insecticidal activity.

• Corrosion Science and Technology
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• v.7 no.2
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• pp.112-118
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• 2008

We observed initial rusting process of steel containing Al under wet/dry cyclic condition with NaCl solution film using in situ X-ray diffraction spectroscopy at SPring-8 synchrotron radiation facility. It was found that mass fraction of iron oxides such as ${\alpha}-FeOOH$, ${\beta}-FeOOH$ and ${\gamma}-FeOOH$ varied with Al content. Some kinds of Al oxides were also found at the initial stage of corrosion. Those corrosion products might affect the corrosion process and corrosion rate of the steel.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.1
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• pp.44-49
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• 2018

High-strength plastic water supply pipe evaluation method was evaluated in this study. Up to date, high strength water supply pipes that we install are mostly ductile cast iron pipes. Sometimes, a few PVC pipes are installed. Metal pipes have rust problem on the surface, causing serious damage to metal pipes and reducing the expected life span of water piping system. Nowadays, depending on technology development, some companies have improved properties of general PVC pipe performance with remarkable properties that exceed KS and ASTM standard. Here, we suggest a new method of performance evaluation for high-strength water plastic pipes.