• Advances in nano research
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• v.8 no.2
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• pp.103-114
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• 2020

In this research, buckling and free vibration of rectangular polymeric laminate reinforced by graphene sheets are investigated. Various patterns are considered for augmentation of each laminate. Critical buckling load is evaluated for different parameters, including boundary conditions, reinforcement pattern, loading regime, and laminate geometric states. Furthermore, vibration analysis is investigated for square laminate. Elastic properties of the composite are calculated using a combination of both molecular dynamics (MD) and the rule of mixture (MR). Kinematics of the plate is approximated based on the first shear deformation theory (FSDT). The current analysis is performed based on the energy method. For the numerical investigation, Ritz method is applied, and for shape functions, Chebyshev polynomials are utilized. It is found that the number of layers is effective on the buckling load and natural frequency of laminates which made from non-uniform layers.

• Animal cells and systems
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• v.2 no.2
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• pp.203-208
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• 1998

A new species of harpacticoid copepod Alteuthoides affinis associated with the sponge Callyspongia elegans (Thiele) was collected from offshore waters of Cheju Island, Korea, and is described with illustrations. In this genus, only one species, A. kootare Hicks, has been known to occur in association with an hexacnellid sponge from New Zealand. The new species is similar to A. kootare in the general morphologies such as the shape of body, oral appendages, and thoraxic legs. However, it can be separated from A. kootare by the expanded genital double semite, P1 exopod bearing only one claw without reduced accessary nail, and acute rostrum.

• Bulletin of the Korean Chemical Society
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• v.22 no.7
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• pp.689-692
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• 2001

An imprinting technique with labile covalent interactions has been developed in the design of new polymer catalysts. The template monomer 2 was prepared and copolymerized with DVB or EDMA to provide the polymer with a cavity having the shape of th e transition state of the reaction as well as binding sites for the substrate and catalytic functionalities. The rate of hydrolysis of diphenyl carbonate (1) in the presence of the imprinted polymer IP-DVB-THF was found to be 120 times faster than the background uncatalyzed reaction. A Km of 32 mM and a kcat of 1.8 ${\times}$ 10-3min-1 were observed from Michaelis-Menten kinetics with the imprinted polymer IP-DVB-THF.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.501-509
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• 1997

In recent papers[Bull. Kor. Chem. Soc. 1996, 17, 735; ibid 1997, 18, 478] we reported results of molecular dynamics (MD) simulations for the thermodynamic, structural, and dynamic properties of liquid normal alkanes, from n-butane to n-heptadecane, using three different models. Two of the three classes of models are collapsed atomic models while the third class is an atomistically detailed model. In the present paper we present results of MD simulations for the corresponding properties of liquid branched-chain alkanes using the same models. The thermodynamic property reflects that the intermolecular interactions become weaker as the shape of the molecule tends to approach that of a sphere and the surface area decreases with branching. Not like observed in the straight-chain alkanes, the structural properties of model Ⅲ from the site-site radial distribution function, the distribution functions of the average end-to-end distance and the root-mean-squared radii of gyration are not much different from those of models Ⅰ and Ⅱ. The branching effect on the self diffusion of liquid alkanes is well predicted from our MD simulation results but not on the viscosity and thermal conductivity.

• Animal Systematics, Evolution and Diversity
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• v.38 no.3
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• pp.144-147
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• 2022

The polychaete Scolelepis (Scolelepis) sagittaria was originally described from Japanese waters and subsequently reported from Korean waters. In this study, we determined for the first time the mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA (16S rDNA), and nuclear 18S ribosomal DNA (18S rDNA) sequences of Korean specimens of S. (S.) sagittaria. We also assessed intraspecific variation in the shape of the prostomium of this species based on an examination of 247 individuals. All materials were collected from intertidal sandy beaches of the Korea Strait. The molecular data and morphological observations reported herein will contribute to gaining a better understanding of the taxonomic relationships among members of the genus Scolelepis.

• Journal of Magnetics
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• v.9 no.2
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• pp.37-39
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• 2004

Polycrystalline Ni-Mn-Ga films have been deposited onto mica substrates held at 720 K by flash-evaporation method. At room temperature the films have a tetragonal structure with a = b = 0.598 and c = 0.576 nm typical for bulk $Ni_2MnGa$ below a martensitic transformation. Temperature measurements of ferromagnetic resonance reveal a martensitic phase transformation at 310 K. The transformation brings about a substantial decrease in the effective magnetization and a drastic increase in the ferromagnetic resonance linewidth due to a strong increase in the magnetic anisotropy in the martensitic phase.

• Korean Journal of Materials Research
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• v.9 no.5
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• pp.473-477
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• 1999

Xerographic properties of double-layer photoconductor doped with 4-butyl-4'-methoxyazobenzene (BMAB) as charge-carrier transport material were investigated. BMAB can undergo reversible trans-cis isomerization by light with appropriate wavelength. In the results of measured surface voltage properties for photoconductor doped with BMAB, TNF: BMAB(4-wt%) sample with trans form showed the lowest dark decay, the lowest residual voltage, and the highest sensitivity among cis form. The trans isomer of BMAB has ordering orientation because the molecule possesses a rodlike shape, while the cis isomer has random orientation due to its bent shape. Therefore the molecular arrangement of trans form enhanced charge-carrier transport mobility.

• The Plant Pathology Journal
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• v.29 no.3
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• pp.317-322
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• 2013

For the past two decades, the causal agent of anthracnose occurring on strawberry in Korea was considered Colletotrichum gloeosporioides. However, the recent molecular analysis has shown that the genus Colletotrichum has undergone many taxonomic changes with introduction of several new species. As a result, it revealed that C. gloeosporioides indeed consisted of more than 20 distinct species. Therefore, the Korean pathogen isolated from strawberry should be reclassified. The shape and size of the conidia of the pathogen were not distinctly different from those of C. gloeosporioides and C. fructicola, but it differed in shape of the appressoria. A combined sequence analysis of partial actin, glyceraldehydes-3-phosphate dehydrogenase genes, and the internal transcribed spacer regions showed that the strawberry isolates formed a monophyletic group with authentic strains of C. fructicola. On the basis of these results, the anthracnose fungi of the domestic strawberry in Korea were identified as C. fructicola and distinguished from C. gloeosporioides.

• Korean Journal of Veterinary Service
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• v.36 no.4
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• pp.273-281
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• 2013

This study investigated the effects of the alkaline detergent and acid rinse used for cleaning milking machines on the eight commercially available teatcup liner materials. The sample liners prepared for use in the clean-in-place process were analyzed by ultraviolet spectrophotometer, ion chromatography and liquid chromatography. Among the eight liner materials, the ultraviolet spectra of 3 sample liners were shown to have a similar peak shape after cleaning, but the ultraviolet spectra peak shape of 5 sample liners was noticeably changed. No products were detected by ion chromatography in any of the liner materials used in this study. When the liner materials were only treated with alkaline detergent, some additional peaks were observed using liquid chromatography which indicate the creation of molecular substance and elution from liner materials, however, these peaks disappeared when the liner materials were cleaned with the acid rinse. Therefore, we propose that an acid rinse should be applied, after cleaning the milking machine with the alkaline detergent.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.56-56
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• 2018

토마토에서 과형은 과실의 여러 가지 형질 중에서 눈에 가장 잘 띄는 형질이며, 소비자의 토마토를 구매를 결정하는데 많은 영향을 미치는 중요한 형질이다. 토마토의 과형을 결정하는 여러 가지 유전자 중에 OVATE는 둥근 토마토 과일을 서양 배 모양(pear shape)의 과일로 전환하는데 결정적인 역할을 하는 유전자이다. OVATE 유전자에 의해서 과일의 모양이 변하는 것은 조기종결 코돈을 초래하는 열성 돌연변이에 의해서 유도되며, 단백질의 C-말단 영역이 제거됨에 따라 그 기능을 상실하여 나타나는 현상이다. OVATE 유전자는 주로 식물의 생식기관에서 발현되며, 꽃에서는 개악하기 10일전부터부터 전사체가 만들어지고 발달중인 과실에서는 개약 후 8일까지 전사체를 확인할 수 있다. 토마토 분자육종 과정에서 과형 판별을 위해서 OVATE 유전자 연관 분자표지는 보고된 바 있으나 OVATE 유전자 유래 분자표지는 보고된바가 없다. 본 연구에서 국내에서 육성된 육종 라인들의 resequencing을 통해 OVATE 유전자 염기서열간의 SNP를 발견하고 이들을 dCAPS 마커로 전환하여 분자표지를 개발했다. 이러한 분자표지는 둥근 토마토(round)와 서양 배모양(pear shape)토마토 육종 프로그램의 효율성과 정확성을 향상시키는데 활용할 수 있을 것으로 기대한다.