• Textile Coloration and Finishing
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• v.19 no.2
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• pp.44-49
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• 2007

Antimicrobial fibers were prepared by an electro-spinning method. Polystyrene hydantoin(PSH) was employed as an antimicrobial precursor to produce an electro-spun antimicrobial acrylic fiber. Increasing the surface area of hydrophobic antimicrobial-fibers provides enhanced antimicrobial efficacy. The biocidal activity of electro-spun acrylic fibers could be rendered through chlorine bleach treatment, and the antimicrobial effectiveness against gram-Positive and gram-negative bacteria was investigated. In addition, scanning electron microscopy(SEM) demonstrated the feature of the electro-spun fibers.

• Food Science and Industry
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• v.52 no.4
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• pp.346-357
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• 2019

In recent years, starch nanoparticles (SNPs) have been received much attention due to their unique characteristics different from native starch. Also, SNPs have economic and environmental advantages because they are prepared from starch, a cheap and safe natural polymer. It can be used in various industrial applications such as food additives, drug carriers, etc. SNPs have been prepared using different methods and their physiochemical, functional properties and possible industrial applications have been reported. Based on these studies, SNPs are expected to be the promising food materials and expand their utilization in many industries in the future. This review covered the overall researches on SNPs, including preparation, physicochemical and functional properties, and discussed their current and future applications including resistant starch materials.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.149-155
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• 2011

This study was carried out to develop a method of removing unnecessary sugars and high-molecular weight soluble components from water extract by using various highly porous polymer resins: these resins are widely used as adsorbents for polyphenolic compounds. Each anthocyanin-rich fraction (ARF) that was eluted from column packed with 4 different resins (SEPABEADS SP207, 700, 850 and Diaion HP 20) was obtained from an aqueous extract of the ripe fruits of Rubus coreanus, which is well-known in Korea as "Bok-bun-ja". Among the above mentioned resins, Diaion HP20 had the highest efficacy and provided maximum yield of the ARF. The ARF eluted from the column packed with HP 20 exhibited the strongest antioxidant activity in vitro. Bioactive phytochemicals extracted from Rubus coreanus were investigated using the on-line HPLC-$ABTS^{{\cdot}+}$ system, and the resulting 6 peaks were identified as radical-scavenging components. By using liquid chromatography-mass spectrometry, 5 peaks were obtained, and these were identified as cyanidin-3-sambubioside, cyanidin-3-glucoside, cyanidin-3-xylosylrutinoside, cyanidin-3-rutinoside and pelargonidin-3-rutinoside. These results indicate that the use of appropriate porous resin (Diaion HP 20) leads to an increase in the yield of bioactive components and enhancement of their biological properties.

• Fibers and Polymers
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• v.4 no.3
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• pp.107-113
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• 2003

The branched polypropylene (b-PP) was prepared by melt blending process with initiator, antioxidant, and functional monomers to improve the melt strength through the melt grafting. The melt flow index (MFI) of the b-PP was increased with increasing the initiator content. On the introduction of the alkylamine as the branching agents the MFI of the b-PP was increased, while that of the b-PP with the pentaerythritol triacrylate (PT) was decreased. It may be caused by the chain scission of the i-PP backbone due to the reduced thermal stability of the i-PP on the melt blending. The MFI of the b-PP without the antioxidant was increased due to the chain scission occurred during the melt processing, while on the introduction of the antioxidant, the MFI of the b-PP was decreased. The crystallization temperature of the b-PP was higher than that of PP, which was attributed to the branched chain structure. It was found that the PT was the most effective functional monomers for enhancing the melt properties of the b-PP.

• Food Science and Preservation
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• v.5 no.1
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• pp.97-104
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• 1998

The chemical structure of low molecule polyphenol of tea was found as explained. Structure decision of pioanthocyanidin was possible to measure 1,700 molecule, hexamer by chemical basic of polyphenol. At present, structure of high molecule than of that can't be suspected and it is concemed that strong astrigent ccnpound of tea is polymer proanthocyanidin. Mush researches was required in structure decision and isolation of high molecule polyphenol complex. Structure decision will develope at the natural products in the furture.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.683-686
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• 2008

$\beta$-Glucans, which were isolated from sangwhang (Phellinus linteus), were subjected to reductive amination and the biological properties of the derivative were investigated. The degree of substitution of the aminated sangwhang $\beta$-glucan was calculated by elemental analysis to be 1.13. Bronchoalveolar lavage (BAL) experiments showed that the aminated derivative increased nitric oxide production. In addition, the amination enhanced in vitro cytotoxic activities against HT1080 and SNU-C2A cell lines. Thus, the aminated derivative is shown to enhance immune systems by the incorporation of amino groups into the polymer structure.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.19-23
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• 2000

The increasing use of plastics in food packaging materials has led to the issue of food-packaging mutual interactions from residues in the plastics. Plastic films are commonly printed by using solvent-based ink to decorate the packaged food for consumer attention. However, the residual solvents can not be completely removed and they can migrate into the contained food which lead to undesirable off-flavors. Partitioning (Kp) of printing ink solvents was studied in two types of plastic films with different chemical structure and polarity. At $25^{\circ}C$, Kp of toluene is higher than that of isopropanol in PP, but isopropanol showed higher Kp value than toluene in EVOH. This showed that polarity had a significant effect on the partitioning of printing ink solvents into the plastic films. Printing solvents had a higher affinity to the polymer with similar polarity than it did to the different one.

• Korean Journal of Pharmacognosy
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• v.33 no.3 s.130
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• pp.257-261
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• 2002

Each ferritin molecule consists of light subunit 19,000 dalton and heavy subunit 22,000 dalton. Twenty-four protein subunit about $440,000{\sim}500,000$ dalton apoferritin which contained $20{\sim}30%$ Fe as ferric hydroxyphosphate polymer form. Horse spleen-derived ferritin consists of 90% light subunit. These genetic characteristics of ferritin preparations were able to determine by cellulose acetate electrophoresis, but these ferritin preparations contained other components to be disturbed during refining, extraction and making finish products and have difficulties in deciding to be just. So, this study was performed to establish the scientific method for determine the quality of ferritin preparations with immunodiffusion methods which has high specificity between heterogeneous proteins.

• Microbiology and Biotechnology Letters
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• v.26 no.1
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• pp.83-88
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• 1998

Heavy metal removal by Z. ramigera 115 and soluble slime polymer producing mutant Z. ramigera 115SLR was investigated. Both strains showed similar tolerance against $Cd^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Ni^{2+}$ and $Fe^{2+}$. When cells were cultivated in the presence of 500 ppm $Cd^{2+}$, the mutant strain removed 1.5 fold more metal than the wild type did at same biomass. Metal adsorption capacities were in the order of Z. ramigera l15SLR polymer > Z. ramigera 115 polymer > Z. ramigera 115 cell >Z. ramigera l15SLR cell. The optimum pH for metal adsorption was 7.5. Langmuir and Freundlich isotherms indicated that Qmax and 1/n of Z. ramigera l15SLR polymer were 164.2 mg $Cd^{2+}$/g dw and 0.496, respectively. These results showed that the polymer of Z. ramigera l15SLR could be used as an effective metal adsorbate.

• Elastomers and Composites
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• v.6 no.1
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• pp.71-81
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• 1971

The intention of this study is to investigate the properties of polymer blend, NBR/PVC vulcanizates and blending procedures such as roll-mixing temperatures and sequences for polymer blending of NBR and PVC(resin type). The results obtained are as follows: 1. The roll temperature applied for polymer blending is around $150^{\circ}C$. At this temperature region, the degradation of rubber stock, which may be caused by heat, can be minimized and mill processing in practical application in industries can also be facilitated. 2. It is obviously necessary that a small amount of plasticizers should be added to the stock for improving processibility of roll mixing and physical properties. 3. On roll-mixing sequence, it is more effective that PVC compounded with plasticizer is added to NBR milled on hot roll. 4. The vulcanizates of the blends with different degree of polymerization of PVC ale similar to one another in properties. 5. NBR/PVC(70/30) blends shows the better physical characters than eve,-made foreign latex blend except abrasion-resistance. 6. As PVC addition ratio is increased, the physical properties such as resistance to ozone, tear, heat and oil and tensile strength, modulus, hardness have also improved, on the other hand, tension set and rebound character decreased. 7. The curve of ultimate elongation have point of inflection at the ratio of $30\sim40$ part of PVC. 8. While CR is blended, the physical properties such as brittle point, rebound and resistance to oil in high temperature have improved. 9. Polymer blend of NBR and domestic PVC is applied for the industrial utility such as rubber sole and heel, electric wire cover and oil-resistant packing, coating and gasket, printing roll, film for food packing etc.