• Journal of the Korean institute of surface engineering
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• v.54 no.1
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• pp.18-24
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• 2021

KNN is widely used in the electronic industry such as memory devices, sensors, and capacitors due to various structural, electrical, and eco-friendly properties. In this study, Mn-doped KNN was prepared by adopting a sol-gel method with advantages of low cost and large area thin film fabrication. The Mn-doped KNN thin films were deposited by annealing in air for 1 hour and 700℃. The surface morphology characteristics and grain size of the heat-treated KNN were observed by SEM and AFM, and we used the X-ray diffraction for measuring the crystal phase of KNN. The XRD analysis results show that the fabrication of (K0.5Na0.5)(Nb1-xMnn)O3 thin films by sol-gel method in the thin film process of this experiment was stable in the perovskite phase of c-axis orientation. The SEM and AFM results show that the cracks were not confirmed from the fracture surface data of KNN thin films and were densely deposited with thin films with uniform thickness.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.527-535
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• 2021

Sclerostin (SOST), a regulator of bone formation in osteocytes, inhibits the canonical Wnt signaling by interacting with low-density lipoprotein receptor-related protein 5/6 (LRP5/6) to prevent Wnt binding. Loss-of-function mutations of the SOST gene caused massive bone outgrowth and SOST-null mouse exhibited a high bone density phenotype. Therefore, SOST has been suggested as a promising therapeutic target for osteoporosis. A few previous studies with X-ray crystallography identified the binding interfaces between LRP6 and SOST, but there are limitations in these studies as they used truncated SOST protein or SOST peptide. Here, we analyzed the conformational dynamics of SOST-LRP6 E1E2 complex using hydrogen/deuterium exchange mass spectrometry (HDX-MS). We examined the effect of the C-terminal tail of SOST on LRP6 conformation upon complex formation. HDX-MS analysis suggested a new potential binding interface for the C-terminal region of SOST that was missing from the previous crystal structure of the SOST-LRP6 E1E2 complex.

• Clean Technology
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• v.15 no.4
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• pp.239-244
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• 2009

$Mg(OH)_2$ slurry was prepared by using natural mineral brucite mined in Liaoning province in China, and its de-$SO_x$ efficiency was compared with that of $Mg(OH)_2$ slurry prepared by thermal decomposition and hydration of magnesite. The physical and chemical characteristics of $Mg(OH)_2$ Powders prepared from brucite and magnesite were similar. However, the layered plate structure of $Mg(OH)_2$ crystal particles prepared from brucite had grown more stably. The desulfurization efficiency of $Mg(OH)_2$ slurry prepared from brucite was slightly higher than that of magnesite. Brucite may be used as a new absorbent for the desulfurization of flue gas in the future.

• Journal of Marine Life Science
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• v.3 no.1
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• pp.1-8
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• 2018

Myosin is considered as the vital motor protein in vertebrates and invertebrates. Our present study was conducted to decipher the occurrence of myosin in dog fish (Squalus mitsukurii). We isolated one clone containing 979 bp cDNA sequence, which consisted of a complete coding sequence of 453 bp and a deduced amino acid sequence of 150 amino acids from the open reading frame with molecular weight, isoelectric point and aliphatic index are 16.72 Kda, 4.49 and 78.00, respectively. It contained 428 bp long 3' UTR with single potential polyadenylation signals (AATAAA). The predicted EF CA²⁺ binding domains were identified in residue 6-41, 83-118 and 133-150. A BLAST search indicates this protein exhibits a strong similarity to whale shark (Rhincodon typus) MLC3 (91% identical) and also house mouse (Mus musculus) MLC isoform 3f (81% identical). Phylogenetic analysis revealed that this protein is a MLC 3 isoform like protein. This protein also demonstrates highly conserved region with other myosin proteins. Homology modeling of S. mitsukuri was performed using crystal structure of Gallus gallus skeletal muscle myosin II based on high similarity. Reverse transcription-polymerase chain reaction (PCR), quantitative PCR results exhibits dogfish myosin protein is highly expressed in muscle tissue.

• Corrosion Science and Technology
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• v.23 no.1
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• pp.1-10
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• 2024

Oil well casing leak is caused by contact of casing outer surface with formation electrolyte. It is usually associated with an aquifer with a high salt content or absence of a cement ring behind the casing. The only way to reduce external casing corrosion is through cathodic protection. Through cathodic polarization of casing structure, electron content in crystal lattice and electron density will increase, leading to a potential shift towards the cathodic region. At Tatneft enterprises, cathodic protection is carried out according to cluster and individual schemes. The main criterion for cathodic protection is the size of protective current. For a casing, the protective current is considered sufficient if measurements with a two-contact probe show that the electric current directed to the casing has eliminated all anode sites. To determine the value of required protective current, all methods are considered in this work. In addition, an analysis of all methods used to determine the minimum protective current of the casing is provided. Results show that the method of measuring potential drop along casing is one of the most reliable methods for determining the value of protective current.

• Fire Science and Engineering
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• v.15 no.1
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• pp.108-115
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• 2001

In this paper, we analyzed the properties change of electric wire when the thermal stress was applied to 600V grade polyvinyl chloride insulated wire (IV). In the structure analysis, normal wire has the properties of direction on the surface, but in case of deteriorated wire at above $400^{\circ}c$, it formed the carbide, the crack and the crystal. The surface composition rate of normal wire was Cu : 100%, but the section composition of the deteriorated wire at $800^{\circ}c$ showed Cu : 78.89%, O : 21.11%. In result of analyzing the differential scanning calory of copper wire, the new reaction peak was observed on the deteriorated wire at above $700^{\circ}c$. In case of the deteriorated wire as $150^{\circ}c$ at the differential thermal analysis, an endothermic reaction appeared at $264^{\circ}c$ lower than the reactive point of normal wire. The occupation rate of oxygen according to the deterioration of copper wire is about 20% at $500^{\circ}c$.

• Journal of Conservation Science
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• v.32 no.4
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• pp.571-578
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• 2016

This study analyzed the pigments used in two portraits of Sim Hui-su using scanning electron microscopy/energy dispersive spectroscopy(SEM/EDS), X-ray diffraction(XRD) analysis, and microscopic observation, and then compared the results to those from nondestructive analysis. It was estimated that cinnabar/vermilion and minium were used for the red pigment, azurite for the blue pigment, atacamite for the green pigment, and lead white for the white pigment. These results were compared to the pigments of six portraits with a similar format, full-length official-attire portraits from the $17-18^{th}$ century Joseon period. It was revealed that the composition of the pigments used in the portraits varied depending on the date of production. Iron oxide, another red pigment, was used in the $18^{th}$ century. As for the blue colorant, smalt was used in the late $18^{th}$ century, whereas it was absent until the early $18^{th}$ century.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.99-99
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• 2008

To grow the large diameter GaN with high structure and optical quality has been obtained by hydride vapor phase epitaxy(HVPE) method. In addition to the nitridation of $Al_2O_3$ substrate, we also developed a "step-growth process" to reduce or to eliminate the bowing of the GaN substrate caused by thermal mismatch during cool down after growth. The as-grown 380um thickness and 75mm diameter GaN layer was separated from the sapphire substrate by laser-induced lift-off process at $600^{\circ}C$. A problem with the free-standing wafer is the typically large bowing of such a wafer, due to the built in the defect concentration near GaN-sapphire interface. A polished G-surface of the GaN substrate were characterized by room temperature Double crystal X-ray diffraction (DCXRD), photoluminescence(PL) measurement, giving rise to the full-width at half maximum(FWHM) of the rocking curve of about 107 arcsec and dislocation density of $6.2\times10^6/cm^2$.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.441-442
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• 2012

SnNb2O6 nanoplates were prepared by a solvothermal synthesis with water and ethanol mixed solvent. For improvement of their properties, as-prepared SnNb2O6 nanoplates also were calcined. The prepared powder was characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), Transmission electron microscope (TEM), UV-vis spectroscopy, Raman spectrometer, Brunauer-Emmett-Teller (BET). The calcined nanoplates have a smaller surface area than the as-prepared nanoplates have. Nevertheless, in the case of the optical absorption properties, the calcined nanoplates could absorb more photon energy, due to their smaller band gaps. The Raman analysis revealed that the Nb-O bond length in the calcined nanoplates was longer than that in the as-prepared nanoplate. The higher optical absorption capability of the calcined nanoplates was attributed to the local structure variation within them. Furthermore the high crystallinity of the calcined nanoplates is effective in improving the generation of charge carriers. So, It was found that the calcined nanoplates exhibited superior photocatalytic activity for the evolution of H2 from an aqueous methanol solution than the as-prepared nanoplates under UV and visible irradiation. Therefore, the enhanced photocatalytic activity of the calcined nanoplate powder for H2 evolution was mainly attributed to its high crystallinity and improved optical absorption property resulting from the variation of the crystal structure.

• Genomics & Informatics
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• v.13 no.1
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• pp.15-24
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• 2015

Fatty acid synthase (FASN, EC 2.3.1.85), is a multi-enzyme dimer complex that plays a critical role in lipogenesis. This lipogenic enzyme has gained importance beyond its physiological role due to its implications in several clinical conditions-cancers, obesity, and diabetes. This has made FASN an attractive pharmacological target. Here, we have attempted to predict the theoretical models for the human enoyl reductase (ER) and ${\beta}$-ketoacyl reductase (KR) domains based on the porcine FASN crystal structure, which was the structurally closest template available at the time of this study. Comparative modeling methods were used for studying the structure-function relationships. Different validation studies revealed the predicted structures to be highly plausible. The respective substrates of ER and KR domains-namely, trans-butenoyl and ${\beta}$-ketobutyryl-were computationally docked into active sites using Glide in order to understand the probable binding mode. The molecular dynamics simulations of the apo and holo states of ER and KR showed stable backbone root mean square deviation trajectories with minimal deviation. Ramachandran plot analysis showed 96.0% of residues in the most favorable region for ER and 90.3% for the KR domain, respectively. Thus, the predicted models yielded significant insights into the substrate binding modes of the ER and KR catalytic domains and will aid in identifying novel chemical inhibitors of human FASN that target these domains.