• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.41-46
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• 1996

Durable softening water repellents such as PODCWs were prepared by blending cationized compound of poly(octadecyl methacrylate-co-2-diethylaminoethyl methacrylate), of which synthetic methods were reported in the previous paper, activated polythylene, waxes, and emulsifiers. Water repellency of prepared PODCWs was measured by performing water repellent finish to various fabrics, PODCWs showed a good water repellency for P/C blended fabrics and their repelling tendency was in the order of P/C blended fabrics>cotton fabrics>nylon taffeta. The initial water repellencies of PODCW-1 and PODCW-2 were 100 and $100^{-}$ points, respectively, for P/C blended fabrics. And also, PODCW-1 and PODCW-2 were confirmed as durable water repellents with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

• Journal of the Korean institute of surface engineering
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• v.52 no.2
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• pp.84-89
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• 2019

We fabricated durable anti-reflective(AR) layer with silica globular coating on polymer by two steps. Firstly, nano-protrusions of polymer were formed by plasma etching known as R.I.E(reactive ion etching) process. Secondly, silica globular coating was deposited on polymer nano-protrusions for mechanically protective and optically enhancing AR layers by RF magnetron sputter. And then durable antireflective polymers were synthesized adjusting plasma power and time, working pressures of RIE and RF sputtering processes. Consequently, we acquired the average transmission (94.10%) in the visible spectral range 400-800 nm and the durability of AR layer was verified to sustain its transmission until 5,000 numbers by rubber test at a load of 500 gf.

• Advances in materials Research
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• v.7 no.2
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• pp.119-136
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• 2018

In this paper, static and vibration analysis for anti-symmetric cross-ply and angle- ply carbon/glass hybrid laminates rectangular composite plate are presented. In this analysis, the equations of motion for simply supported thick laminated hybrid rectangular plates are derived and obtained through the use of Hamilton's principle. The closed-form solutions of anti-symmetric cross-ply and angle- ply laminates are obtained using Navier solution. The effects of side-to-thickness ratio, aspect ratio, and lamination schemes on the fundamental frequencies loads are investigated. The study concludes that shear deformation laminate theories accurately predict the behavior of composite laminates, whereas the classical laminate theory over predicts natural frequencies. The excellent accuracy of the present analytical solution is confirmed by making some comparisons of the present results with those available in the literature. It can be concluded that the proposed theory is accurate and simple in solving the free vibration behaviors of anti-symmetric cross-ply and angle- ply hybrid laminated composite plates.

• Textile Coloration and Finishing
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• v.33 no.2
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• pp.64-71
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• 2021

Large amount of formaldehyde could be released inevitably during the flame-retardant (FR) treatments or from the finished fabrics using Provatex reagent and Proban polymers which have been used as durable FRs for cotton. A water-soluble cyclophosphazene derivative was synthesized as an ecofriendly phosphorus-based FR for cotton fibers. Dichloro tetrakis{N-[3-(Dimethylamino)propyl]methacrylamido} cyclcophosphazene (DCTDCP) was synthesized through the substiutution reaction of Hexachloro cyclophosphazene and N-[3-(Dimethylamino)propyl] methacrylamide at a mole ratio of 1 : 4, which can be cured dually by both alkaline treatment and UV irradiation. More crosslinked networks were produced through the addition of Triacryloyl hexahydrotriazine and Acrylamide as a UV-curable crosslinker and a comonomer respectively. Both flame retardancy and washing durability of the FR cotton were improved synergistically. The durability improvement may be caused by the covalent bond formation of the FR with cellulose and the high degree of polymerization of DCTDCP, which can be verified by the pyrolysis and combustion behaviors analyzed by LOI, TGA, and microcalorimeter.

• Asia-Pacific Journal of Business
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• v.10 no.4
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• pp.119-135
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• 2019

This study analyzes the effects of trade globalization and financial globalization on consumption classified by type(durable, quasi-durable, non-durable and service). On the other hand, trade globalization and financial globalization were decomposed into OECD common factor, regional factors, and the idiosyncratic country-specific factors by time-varying dynamic factor analysis. The characteristics of OECD common factor, regional factors, and the idiosyncratic country-specific factors of trade and financial globalization were analyzed. Furthermore, the influences of these factors on consumption by type were analyzed. The analysis shows that globalization has negative effects on consumption. In particular, we found out that the idiosyncratic country-specific factor of Korea in trade and financial globalization had a statistically significant negative effect on consumption. We can infer that the globalization affecting consumption can be attributed to the idiosyncratic country-specific factor, which is economic choice rather than uncontrollable global trend. Accordingly, to solve the sluggish consumption problem caused by globalization, it is necessary to require not only domestic consumption expansion policies but also the efforts to resolve economic polarization problems to be able to stimulate consumption.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.1-9
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• 2022

The durable FR treatments such Pyrovatex and Proban have been used for cotton fibers, while the finishes involve toxic ammonia or formaldehyde release during finishing process or finished products. In this study, ecofriendly flame-retardant treatment of cotton fabrics was carried out using UV-curable formulations of Vinyl bisphosphonic acid (VBPA), Acrylaminide and Triacryloylhexahydro-1,3,5-triazine, as a monomer, a comonomer and a cross-linking agent respectively, which can introduce a cross-linked copolymer networks. With an optimal finish formulation, the flame retardancy of LOI 29.8 was maintained even after 10 laundering cycles. In TGA analysis, the DTGA peak decreased from 389℃ to 252℃ and the amount of char yield increased from 6.1% to 46.1% compared to the untreated cotton. In addition, MCC analysis showed that Peak HR and THR decreased by 59.4% and 69.2% respectively, compared to the untreated cotton. The pyrolysis and combustion behaviors of the FR-treated cotton implied a condensed-phase flame-retarding mechanism.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.230-237
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• 2021

The flame-retardant (FR) treatments of wool fibers using Hexafluorozirconate/titanate salts and tetrabromophthalic anhydride can cause skin irritation and gas toxicity due to Zr and Br compounds respectively. A water-soluble polyfunctional cyclophosphazene derivative, synthesized through substitution reaction of Hexachloro cyclophosphazene and N-[3-(Dimethylamino)propyl] metacrylamide, was applied as a durable flame-retardant for wool fabrics. Also, a crosslinked structure was introduced to improve washing durability of the FR-wool, up to 10 laundering cycles, using Acrylamide(AAm) and Triacryloylhexahydrotriazine (TAHT) as a comonomer and a crosslinker respectively. The mole ratios of the TAHT and AAm concentrations compared to the Dichloro tetrakis{N-[3-(Dimethylamino)propyl]methacrylamido} cyclcophosphazene (DCTDCP) were optimized to 1.33 and 7.5 respectively. In addition, the pyrolysis and combustion properties of the FR wool were assessed using LOI, TGA and microcalorimetry suggesting a solid-phase FR mechanism.

• Journal of the Korean Wood Science and Technology
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• v.31 no.3
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• pp.50-60
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• 2003

The main purpose of this study was to propose the development direction and application method of wood as a landscape material by analysis and investigation of the present condition and characteristics of wood, which is a quite interesting natural material for its beauty as an exterior material. This study is based on the relationships between the establishment of development direction and practical use of exterior wood as a landscape material. The research method used was fieldwork and data analysis. On the analysis of the present condition of wood utilization, it was investigated to need of complement of a design aspect, use method, the limit of use type, and use range. The direction of a durable design for the practical use of exterior wood as landscape materials was established. On the use of exterior wood, first, the characteristics of wood have to be understood. Then exterior wood can be used while preserving its safety and beauty over a long time by physical and chemical treatment. At the same time, an application plan for the practical and effective use of wood as an outdoor landscape material, we concluded that future research in design aspects is needed in consideration of physical, chemical, and structural properties of durable wood materials used in outdoor facilities.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.2
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• pp.49-58
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• 2008

Generally, steel corrosion occurs in concrete structures due to carbonation in down-town area and underground site and it propagates to degradation of structural performance. In general diagnosis and inspection, only carbonation depth in sound concrete is evaluated but unsound concrete such as joint and cracked area may occur easily in a concrete member due to construction process. In this study, field survey of carbonation for RC columns in down-town area is performed and carbonation depth in joint and cracked concrete including sound area is measured. Probability of durable failure with time is calculated through probability variables such as concrete cover depth and carbonation depth which are obtained from field survey. In addition, service life of the structures is predicted based on the intended probability of durable failure in domestic concrete specification. It is evaluated that in a RC column, various service life is predicted due to local condition and it is rapidly decreased with insufficient cover depth and growth of crack width. It is also evaluated that obtaining cover depth and quality of concrete is very important because the probability of durable failure is closely related with C.O.V. of cover depth.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.391-402
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• 2021

Earthworms play an important role in soil fertilization, interacting continually with microorganisms. This study aims to demonstrate the existence of beneficial microorganisms living in the earthworm's immune system, the coelomic fluid. To achieve this goal, a molecular identification technique was performed, using cytochrome c oxidase I (COI) barcoding to identify abundant endogenic earthworms inhabiting the temperate zone of Rabat, Morocco. Then, 16S rDNA and ITS sequencing techniques were adopted for bacteria and fungi, respectively. Biochemical analysis, showed the ability of bacteria to produce characteristic enzymes and utilize substrates. Qualitative screening of plant growth-promoting traits, including nitrogen fixation, phosphate and potassium solubilization, and indole acetic acid (IAA) production, was also performed. The result of mitochondrial COI barcoding allowed the identification of the earthworm species Aporrectodea molleri. Phenotypic and genotypic studies of the sixteen isolated bacteria and the two isolated fungi showed that they belong to the Pseudomonas, Aeromonas, Bacillus, Buttiauxella, Enterobacter, Pantoea, and Raoultella, and the Penicillium genera, respectively. Most of the isolated bacteria in the coelomic fluid showed the ability to produce β-glucosidase, β-glucosaminidase, Glutamyl-β-naphthylamidase, and aminopeptidase enzymes, utilizing substrates like aliphatic thiol, sorbitol, and fatty acid ester. Furthermore, three bacteria were able to fix nitrogen, solubilize phosphate and potassium, and produce IAA. This initial study demonstrated that despite the immune property of earthworms' coelomic fluid, it harbors beneficial microorganisms. Thus, the presence of resistant microorganisms in the earthworm's immune system highlights a possible selection process at the coelomic fluid level.