• Proceedings of the Korean Fiber Society Conference
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• 1986.06a
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• pp.26-27
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• 1986

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.11-11
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• 1987

• Proceedings of the Korean Fiber Society Conference
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• 1987.06b
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• pp.18-18
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• 1987

• Computers and Concrete
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• v.21 no.6
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• pp.669-679
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• 2018

In this paper the behavior of reinforced concrete (RC) beam-column connections under cyclic loading was analyzed. The specimens, manufactured in a reduced-scale were made of (a) recycled aggregate concrete (RAC) by replacing 30% of natural coarse aggregate (NCA) with recycled coarse aggregate (RCA) and (b) RAC incorporating Polyethylene terephthalate (PET) fiber i.e., PET fiber-reinforced concrete (PFRC) at the joint region. PET fiber (aspect ratio=25) of 0.5% by weight of concrete used in the PFRC mix was obtained by hand cutting of post-consumer PET bottles. A reference specimen was also prepared using 100% of NCA and subjected to similar loading sequence. Comparing the results the structural behavior under cyclic loading of RAC specimens are quite similar to the reference specimens. Damage tolerance, load resisting capacity, stiffness degradation, ductility, and energy dissipation of the RAC specimens enhanced due to addition of PET fibers at the joint region. PFRC specimens also presented a lower damage indices and higher principal tensile stresses as compared to the RAC specimens. The results obtained gave experimental evidence on the feasibility of RAC for structural use. Using PET fibers as a discrete reinforcement is recommended for improving the seismic performance of RAC specimens.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.4024-4031
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• 2014

Nanofibers have attracted significant interest in many industrial fields because their high surface area and porosity. In addition, the continued use of petrochemical based polymers has caused the depletion of oil resources and accelerated the greenhouse effect by the emission of carbon dioxide. Therefore, biomass-based polymer has become a very important environmentally friendly alternative. In this study, nanofibers were fabricated by an electrospinning process using biomass based PEF(polyethylene furoate) prepared by the polymerization of 2,5-furandicaboxylic acid and ethylene glycol. Furthermore, the electrospun nanofiber was strongly affected by various parameters, such as the solvent, polymer concentration and electric field. In conclusion, nanofibers with an average fiber diameters of 200 - 700 nm could be prepared at polymer concentration of 15 wt% using HFIP, and their fiber diameter increased with increasing electric field.

• KSBB Journal
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• v.9 no.2
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• pp.98-103
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• 1994

A bed configuration wherein sheets of modified fibrous polyethylene are potted within a Millipore Filter Cartridge matrix has been developed. Polyethylene fibers form sturdy beds but the native hydrophobicity and inertness of polyethylene have precluded their use in protein chromatography The polyethylene fibers used in this system were modified by plasma oxidation and further derivatization. The resulting fibers are hydrophilic, bind protein reversibly and serve as an anion-exchange stationary phase. Separation of Bovine Serum Albumin on this bed, as well as results of basic studies on capacity and reversibility of binding within a fibrous bed and experimental data handling system are shown.

• Polymer(Korea)
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• v.32 no.4
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• pp.305-312
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• 2008

A novel TPC-PEG-TPC with active end-groups was obtained from the end-groups of polyethylene glycol (PEG) modified by terephthaloyl chloride (TPC). These active end-groups can link up with a rare earth ion, which is a luminescent center of a rare earth fluorescent complex. Complexes of Eu-PEG with novel ligands (TPC-PEG-PTC) were synthesized by the coordination of the active reactant (as the first ligand) and phenanthroline (as the second ligand) with $Eu^{3+}$.IR, $^1H$-NMR, element analysis, DSC, WAXD, fluorescent spectroscopy, TGA, and SEM were used to characterize the structure and properties of these complexes. The results showed that this type of complex is a heat storage material with the phase change character of polyethylene glycol (PEG) and the luminescent properties of europium. There was no thermal decomposition of the complex of Eu-PEG until $300^{\circ}C$. SEM showed that the complex of Eu-PEG can be dispersed in PE.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.2
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• pp.200-206
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• 1992

The effect of fiber diameter and gauge length on pull-out test for the interfacial properties in fiber reinforced resin composites have been investigated and these results have been arranged as statistical analysis. The fiber and matrix resins used for this study were stainless steel fiber (SUS316) and carbon fiber (high strength type), epoxy and high density polyethylene resin. From this study, it has been found that shear strength are constant regardless of gauge length of pull-out test and coefficient of variation depend on fiber diameter. In addition, it has been found that the interfacial shear strength decreased with the increasing fiber diameter, and in all case, Weibull parameter (m) has approximately 1.2/C.O.V.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.108-111
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• 2004

The polypropylene(PP) fiber is poised as a low cost alternative for reinforcement in structural applications in comparison with other high performance fibers, such as the polyvinyl-alcohol(PVA), polyethylene, carbon and aramid fiber. The mechanical properties of the composite are strongly determined by the interfacial behavior of fiber and cementitious matrix. The crack bridging mechanism contribute to composite toughness from activation of the fiber-matrix interface where energy is dissipated through debonding of the interface and fiber pullout. In this study, therefore, the pullout behavior of PP fibers is investigated. Experimental work includes the investigation of the interfacial properties, and the composite property. The quantification of interfacial properties, the frictional bond is achieved through single fiber pullout test. A study on the effect of inclination angle on fiber pullout behavior is also conducted.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.270-275
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• 2016

High density polyethylene (HDPE)/kenaf fiber (KF) composites included two types of KF with different lengths were fabricated by using a twin screw extruder. A thermally expandable microcapsule (EMC) was used to form HDPE/KF. The KF lengths were 0.3 mm and 3 mm. The contents of KF and EMC were fixed at 20 wt% and 5 wt%, respectively. From FT-IR data of KF, which underwent chemical treatment, peaks around 1700 and $1300cm^{-1}$ decreased. This might be caused by the reduction of lignin and hemicellulose due to the chemical treatment of KF. Based on the specific gravity, thermal stability and tensile property, physical properties of the composites with a 3 mm fiber were good. However, if the fiber is longer, poor appearance might be caused due to the thermal degradation during processing. Thus, the adequate length of KF should be chosen to maintain the appearance and physical properties for industrial applications of HDPE/KF/EMC composites. The tensile strength for 0.3 mm fiber treated with chemicals increased slightly.