• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1314-1319
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• 2007

This study is to compare food components and the sensory properties of common and functional Porphyra yezoensis, Pyroligneous liquor, Salicornia herbacea L. and Salicornia herbacea L. treated with oak charcoal. The samples used in this study were provided by a local manufacturer. We analyzed their proximate composition, mineral content, heavy metal content and amino acids. We conducted the sensory evaluation before and after grilling Porphyra yezoenis. Common components are more plentiful in functional Porphyra yezoenis than in common except for carbohydrate and crude fiber. In the case of mineral content, generally functional Porphyra yezoensis contains much more mineral than common except for magnesium and zinc. Especially Salicornia herbacea L. treated with oak charcoal contains abundant iron. Also, Salicornia herbacea L. contains a lot of calcium potassium, copper and sodium. There is a little more heavy metal except for chromium, cadmium and lead in Salicomia herbacea L. treated with oak charcoal than in common that contains a lot of chromium, cadmium and lead, although a wide difference was not discovered between them. In the case of composed amino acid, there are much glutamic acid, glycine, isoleucine and phenylalanine in both Porphyra yezoensis. Especially alanine and phenylalanine are trebled in functional Porphyra yezoensis. Also, there are far more serine and lysine in Salicornia herbacea L. and Salicornia herbacea L. treated with oak charcoal than in common Porphyra yezoensis and Pyroligneous liquor. In the case of the sensory properties, there isn't a big difference before grilling Porphyra yezoensis; however, after grilling, most functional Porphyra yezoenis had good sensory properties results, especially Salicornia herbacea L. were better than Pyroligneous liquor.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.405-411
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• 1988

In this study, the treatment of $H_2O_2$, papain and acylation on the protein isolate obtained from defatted sesame oil cake for the changes in amino acids composition, color, digestibility and some functional characteristics of this protein were investigated. The results showed that $H_2O_2$, papain and papain $H_2O_2$ treatment increased the rates of the protein extraction and content of protein in protein isolates when those values were compared to the alkali treatment. Also amino acid composition of the protein isolates were comparatively good, and color, and functional properties and pepsin digestibility were markedly improved. The amount of lysine, the first limiting amino acid of this protein was increased. The solubility, bulk density, water absorption, fat absorption and emulsifying properties were remarkably improved while foaming properties and digestibility was slighly decreased.

• Applied Biological Chemistry
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• v.42 no.2
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• pp.128-133
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• 1999

To enhance functional properties of 4 different hoki frame protein hydrolysates (30K, 10K, 5K and 1K hydrolysate) fractionated through a series of 30, 10, 5 and 1 kDa molecular weight cut-off membranes in order to decrease pore size, all hydrolysates were phosphorylated with sodium trimetaphosphate and altered phosphorylated 30K, 10K, 5K and 1K (P-30K, P-10K, P-5K and P-1K), respectively. The covalent attachment of anionic phosphate groups to polypeptide chains improved the functional properties, such as solubility, emulsifying properties and foaming properties, of hoki frame protein hydrolysates. Especially, P-30K hydrolysate with the highest molecular weight fraction possessed the most excellent functional properties among 4 different phosphorylated hydrolysates.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.608-622
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• 2021

Bioactive peptides have great potentials as nutraceutical and pharmaceutical agents that can improve human health. The objectives of this research were to produce functional peptides from ovotransferrin, a major egg white protein, using single enzyme treatments, and to analyze the properties of the hydrolysates produced. Lyophilized ovotransferrin was dissolved in distilled water at 20 mg/mL, treated with protease, elastase, papain, trypsin, or α-chymotrypsin at 1% (w/v) level of substrate, and incubated for 0-24 h at the optimal temperature of each enzyme (protease 55℃, papain 37℃, elastase 25℃, trypsin 37℃, α-chymotrypsin 37℃). The hydrolysates were tested for antioxidant, metal-chelating, and antimicrobial activities. Protease, papain, trypsin, and α-chymotrypsin hydrolyzed ovotransferrin relatively well after 3 h of incubation, but it took 24 h with elastase to reach a similar degree of hydrolysis. The hydrolysates obtained after 3 h of incubation with protease, papain, trypsin, α-chymotrypsin, and after 24 h with elastase were selected as the best products to analyze their functional properties. None of the hydrolysates exhibited antioxidant properties in the oil emulsion nor antimicrobial property at 20 mg/mL concentration. However, ovotransferrin with α-chymotrypsin and with elastase had higher Fe³⁺-chelating activities (1.06±0.88%, 1.25±0.24%) than the native ovotransferrin (0.46±0.60%). Overall, the results indicated that the single-enzyme treatments of ovotransferrin were not effective to produce peptides with antioxidant, antimicrobial, or Fe³⁺-chelating activity. Further research on the effects of enzyme combinations may be needed.

• Polymer(Korea)
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• v.33 no.1
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• pp.45-51
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• 2009

Water soluble adhesive was polymerized from butyl acrylate (BA), methyl methacrylate (MMA) and one of various functional monomers such as acrylic acid (AA), 2-hydroxylethyl methacrylate (2-HEMA), glycidyl methacrylic acid (GMA) and acrylamide (AAm). The amount of the functional monomers was 1$\sim$5 wt%/monomer. In order to improve the adhesive power, a substrate was treated using atmospheric flat plasma method. The adhesive power was improved by the addition of the functional monomers with an order of AA> 2-HEMA> GMA> AAm. The holding power of the adhesives, which is related with the thermal properties of the adhesives, increased with the amount of the functional monomers. The effectiveness in improving the holding power has an order of AA > AAm > GMA > 2-HEMA. By treating a substrate with atmospheric flat plasma method, the adhesives containing each of AA, 2-HEMA, GMA and AAm showed the increases of the final adhesion strength by 9.1, 9.4, 9.4, and 1.8%, respectively. In conclusion, the mechanical properties such as adhesive power and holding power could be controlled by introducing.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1421-1423
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• 2005

A new light-emitting poly(p-phenylenevinylene) (PPV) derivative containing a polyhedral oligomeric silsequioxane (POSS-PPV) and its MEH-PPV copolymers, [Poly(POSSPV-co-MEHPV)]s, have been synthesized through the Gilch polymerization, and their light-emitting properties were investigated. The synthesized polymers were characterized by NMR, GPC, thermogravimetric and elemental analysis. The POSS-PPV and copolymers showed almost the same optical properties as the MEH-PPV, regardless of copolymer composition. The POSS-PPV and MEHPPV all showed their peak absorption at 505 and 496nm, and PL emission maxima at 578 and 581nm. POSSPPV showed higher PL quantum efficiency than the MEH-PPV. Synthesis, characterization and electroluminescent properties of the polymers will be presented.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.11
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• pp.126-133
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• 2008

Rapid Prototyping (RP) has been widely used for rapid development of prototypes in various industrial fields. In recent years, a new requirement in RP industry has issued so as to directly manufacture a functional prototype which has enough mechanical properties to be used as a functional part. The RP prototype, however, has a limitation in mechanical properties due to its layer-by-layer manufacturing process. This manufacturing process results in anisotropy of the prototype, especially showing weakness in the building direction. In the present work, we performed tensile tests for RP prototypes in order to determine directional mechanical properties. The test specimens were made by using $Eden330^{TM}$ by Object Geometries Ltd. Finite element analyses considering material anisotropy were then carried out for RP prototypes with various building directions. Effect of the building direction on the mechanical strength was investigated through the analysis, and compared with experimental results.

• Macromolecular Research
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• v.16 no.1
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• pp.21-30
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• 2008

Based on the sheath-core bicomponent composite fibers with modified polystyrene (PS) and the modified polypropylene (PP), composite fibers obtained were further cross-linked and sulphonated with chlorosulphonic acid to produce strong acidic cation ion exchange fibers. The structures of the fibers obtained were characterized using Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC) etc. The optimal technology of the fibers obtained is discussed. The static absorption capacity of the sheath-core bicomponent composite cation exchange fibers for $Zn^{2+}$, $Cu^{2+}$ was determined. The absorption kinetics and major factors affecting the absorption capacities of $Zn^{2+}$, $Cu^{2+}$ were studied, and its chemical stability and regenerating properties were probed. The results suggest that cation exchange fibers with better mechanical properties and higher exchange capability were obtained. Moreover, this type of ion exchange fiber has good absorption properties and working stability to various metal ions. Hence, they have higher practicability.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.861-873
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• 2022

The drying of duck blood provides safety and commercial benefits, but each drying method has its own characteristics. Moreover, information on the effects of diverse drying methods on the quality of duck blood is limited. This study aimed to investigate the effects of various drying methods on the chemical and functional properties of duck blood. The physicochemical characteristics and functional properties of duck blood subjected to spray drying (SD), freeze drying (FD), vacuum drying (VD), and hot air drying (HD) were examined. The carbonyl content of FD duck blood powder was the lowest and the thermal stability was higher than that of the other treatments (p<0.05). The gel obtained from spray-dried blood displayed the lowest malondialdehyde content. The hardness, gumminess, and chewiness were the highest in the heat-induced gel prepared from FD duck blood powder (p<0.05). The gel obtained from FD duck blood displayed a denser structure than the other gel samples. Taken together, the FD duck blood exhibited excellent chemical properties and processing suitability.

• Elastomers and Composites
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• v.57 no.3
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• pp.100-106
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• 2022

Waterborne polyurethane-acrylate(WPUA) dispersions were prepared by surfactant-free emulsion polymerization in a two-step process. In the first step, polytetrahydrofuran, isophorone diisocyanate, dimethylol proponic acid, and 2-hydroxyethyl methacrylate were used to synthesize a vinyl-terminated polyurethane prepolymer. In the second step, styrene, methyl methacrylate, butyl acrylate, and different multi-functional crosslinkers were copolymerized. 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, and pentaerythritol tetraacrylate were used as the crosslinkers, and their effect on the mechanical and thermal properties of WPUA was investigated. Overall, as the number of functional groups of the cross-linker increased, the gel fraction improved to 79.26%, the particle size increased from 75.9 nm to 148.7 nm, and the tensile strength was improved from 5.86 MPa to 12.40 MPa. In thermal properties, the glass transition temperature and decomposition temperature increased by 9.9℃ and 18℃, respectively. The chemical structures of the WPUA dispersions were characterized by Fourier-transform infrared spectroscopy. The synthesized WPUA has high potential for applications such as coatings, leather coatings, adhesives, and wood finishing.