• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2012.05a
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• pp.38-40
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• 2012

• Fibers and Polymers
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• v.7 no.2
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• pp.158-163
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• 2006

Standard extraction procedure for examining chromophoric substances of turmeric was investigated. Acetone and methanol were used as extracting solvents with different extraction procedures and pH levels. GC-MS analysis identified curcumene 2 (6.7 min), feruloylmethane 3 (8.3 min), coumaran 4 (6.09 min), vanillin 5 (6.2 min), and zingiberene 6 (10.5 min) as the major products. Curcumin 1 which has been known as the major chromophoric substance of turmeric was not detected in any samples. The maximum amount of curcumene 2, which was used as the fingerprint product for turmeric dye, was obtained by utilizing presoaking and decanting step with methanol prior to actual extraction step using a waterbath shaker (WMM). The highest relative abundance of curcumene 2 was detected in pH 6 sample followed by pH 5 indicating that the most appropriate pH level was in the range of pH 6-5.

• Macromolecular Research
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• v.17 no.1
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• pp.8-13
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• 2009

Natural fiber-filled polymer composites have attracted great interest due to increasing environmental concerns and their low costs. In this study, the properties of rice husk flour-filled polypropylene (PP) were analysed in view of the large quantities of this agricultural product available as residue in Brazil. The rice husk flour (RHF) was characterized by SEM and particle size distribution. The properties of the composites were studied by MFI, DMA, DSC and TGA analyses. A commercial PP modified with maleic anhydride (MAPP) was used as coupling agent. It was verified that RHF decreased the MFI of the composites and that the coupling agent decreased it even more. The efficiency of MAPP was confirmed by the high storage modulus and high loss factor of the coupled composites.

• Fibers and Polymers
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• v.5 no.4
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• pp.270-274
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• 2004

Blends of poly(l-lactide) (PLA) and low density polyethylene (LDPE) were prepared by melt mixing in order to improve the brittleness of PLA. A reactive compatibilizer with glycidyl methacrylate (GMA), PE-GMA, was required as a compatibilizer due to the immiscibility between PLA and LDPE. It contributes to reduce the domain size of dispersed phase and enhance the tensile properties of PLA/LDPE blends, especially for PLA matrix blends. A reaction product between PLA and PE-GMA, which was formed during melt-mixing and considered to act as a reactive compatibilizer, was characterized using $ ^1H-NMR$ spectroscopy.

• Natural Product Sciences
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• v.22 no.2
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• pp.134-139
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• 2016

Phytochemicals were isolated from leaves of the fiber crop, ramie (Boehmeria nivea, Bn), using open column chromatography and medium pressure liquid chromatography. Their structures were identified as ${\beta}$-sitosterol, (-)-loliolide, rutin, and pyrimidinedione by MS, $^1H$-, and $^{13}C$-NMR spectroscopic analysis. Among them, (-)-loliolide was isolated for the first time from B. nivea. A content analysis of (-)-loliolide in B. nivea collected from different regions and harvest times was conducted by HPLC. The highest content of (-)-loliolide was found in Bn-23 harvested in September. These results will be helpful to use the plant which harvest in September as a high content phytochemical additive in food, health supplements, and medicinal products.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.1-9
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• 2004

Structure and strengths of paper have been studied by analyzing fibers characteristics depending on refining methods. In those studies stock preparation aspect of softwood and hardwood fibers mixing and fibers characteristics was focused for paper quality improvement. In this study drainage of fibers were analyzed to improve the production efficiency and paper product's quality. Fiber properties by one and two-step refining processes were compared. By applying two-step refining processes($2.8kg_f$ and $5.6kg_f$ of refining load), refining efficiency, drainage, and strengths could be improved at specific extent of refining.

• Journal of the Korean Mathematical Society
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• v.61 no.1
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• pp.41-63
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• 2024

In this paper, we study complete Riemannian immersions into a semi-Riemannian warped product obeying suitable curvature constraints. Under appropriate differential inequalities involving higher order mean curvatures, we establish rigidity and nonexistence results concerning these immersions. Applications to the cases that the ambient space is either an Einstein manifold, a steady state type spacetime or a pseudo-hyperbolic space are given, and a particular investigation of entire graphs constructed over the fiber of the ambient space is also made. Our approach is based on a parabolicity criterion related to a linearized differential operator which is a divergence-type operator and can be regarded as a natural extension of the standard Laplacian.

• Journal of Sensor Science and Technology
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• v.3 no.2
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• pp.50-56
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• 1994

Fiber-optic biosensor for the detection of organophosphorus compounds in a contaminated water was developed, which was the component of pesticides and agricultural agent. The detection principle of designed sensor was the pH variance induced by a reaction of acetylcholinesterase enzyme inhibited by organophosphorus compounds. The pH variance was detected by the optical system to measure the organophosphorus compounds. Litmus was selected as the pH-sensitive dye suitable to the enzyme reaction and a light source to be detected by the optical system. The enzyme entrapped in Ca-alginate gel was immobilized at the inner wall to maintain the high activity of enzyme and to be reused for a long period. The optical fiber was used to miniaturize and control remotely the sensor system. The He-Ne laser with 632 nm was selected as the light source to prevent light intensity fluctuation by the product. Cheap plastic optical fibers were used as the transmission part of the light and the phototransistor was used as the reception part of light based on the wavelength of He-Ne laser. The proposed fiber-optic biosensor has the linear analytical range of 0 ppm-1.5 ppm with response time of 5 minutes.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.145-151
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• 2015

Corn fiber protein (CFP) was extracted from corn wet-milling by-product, corn fiber. CFP films containing various plasticizers and cross-linking agents were prepared and their mechanical properties were determined. Among the plasticizers and cross-linking agents used in this study, the CFP film containing 2 g fructose and 0.03% cinnamaldehyde had the most appropriate physical property. In addition, the CFP films containing green tea extract (GTE) were prepared by incorporating different amounts (0, 0.5, 1.0, 1.5%) of GTE into the film-forming solution. Tensile strength, film solubility, and opacity of the CFP films increased with the addition of GTE, whereas elongation and water vapor permeability of the CFP/GTE films decreased compared to those of the control. The antioxidant activity of the CFP/GTE film was determined in terms of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. As a result, antioxidant activity of the films increased with increasing GTE concentration. Furthermore, antimicrobial activity against Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus increased with increasing GTE concentration. These results indicate that the incorporation of GTE could enhance antioxidant and antimicrobial activities of the CFP films.

• Composites Research
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• v.30 no.3
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• pp.169-174
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• 2017

Demand of glass fiber reinforced composites (GFRC) increased with developing aircraft and defense industries using resin transfer molding (RTM) process to produce complex product. In this research, wetting, interfacial, and mechanical properties were evaluated with different Cross-linking Density by Molecular Weight of Hardener. Epoxy resin as matrices was used bisphenol-A type and amine-type hardeners with different molecular weight. Specimens were manufactured via RTM and wetting property of resin and glass fiber (GF) mat was evaluated to viscosity of epoxy and injection time of epoxy matrix. Mechanical property of GFRC was determined via flexural strength whereas interfacial properties were determined by interlaminar shear strength (ILSS) and interfacial shear strength (IFSS). The difference in mechanical property depends upon the fiber weight fraction (wt %) of GFRC by RTM as well as the different Molecular Weight of Hardener.