• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.564-567
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• 1999

Gelatinization characteristics of pigmented rice varieties were determined in terms of amylose contents, amylograph, gel consistency, water absorption index (WAI) and water soluble index (WSI). Amylose contents of black and red rice were lower than those of brown rice, especially Sanghaehyanghyulla exhibited the lowest amylose contents among the pigmented rice varieties tested. There was no significant difference in WAI among the pigmented rice varieties, but WSI was lower in red rice than the others. Peak viscosity of black rice measured in a Brabender amylograph was lower than those of red and brown rice.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.91-96
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• 2002

This study was carried out to estimate the property of dimensional stability of heat compression of italian poplar wood with low density. Firstly, two levels of pressure conditions were applied using the closed and open-press system. The thermal treatment temperatures were 180℃ and 200℃, respectively. Water absorption tests were conducted in water bath at 25℃ and 100℃ for 35 hours and 1 hour, respectively. The compression rates of wood were 47 percent, 60 percent, and 73 percent, respectively. From these tests, it was found that the dimensional stability of the closed-press system was superior to that of the open-press system. Furthermore, the dimensional stability of compressed wood in the closed-press system was better at 200℃ than 180℃. In compression rate, dimensional stability of 73 percent compression rate was the best result. Considering these results, the best conditions for the dimensional stability of compressed wood were those of the closed-compressing system at high temperatures above 200℃ and larger compression rate. Therefore, it was concluded that the dimensional stability of wood is improved at higher temperature and larger deformation.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.905-911
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• 2005

Physical properties and compositions of dietary fiber sources (DFS) from peels of Asian pear fruit, Hosui, Niitaka and Chuwhangbae, were examined at different growth stages, young, unripe, and ripe fruits, to investigate their use as functional ingredients. Total dietary fiber (TDF) contents of DFS prepared from peels of three cultivars at three stages were high, 74.00-88.38%, with most being insoluble dietary fiber. Total phenolic compound contents of DFS were 1.64-4.46mg/g, with those of Niitaka and Chuwhangbae increasing with growth stages. Density of DFS from young fruit was significantly lower than those from unripe and ripe fruits (p<0.05), because particle size of DFS increased with growth stages within cultivars. Water-holding capacity (WHC) and oil absorption were 3.11-6.03g water/g solid and 1.98-2.57g oil/g sample, respectively. Young fruits, which showed lowest WHC value, had highest oil absorption value. Particle size of DFS had significant correlation with density, WHC, and oil absorption (p<0.05). Physical properties of DFS were mainly influenced by cellulose and uronic acid.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.4
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• pp.470-482
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• 2008

Seasonal variations of chemical composition and optical properties of aerosols at Seoul and Gosan were investigated using the ground-based aerosol measurements and an optical model calculation. The mass fraction of elemental carbon was $8{\sim}17%$, but its contribution on light absorption was high up to $29{\sim}48%$ in Seoul. In Gosan, the contribution of water soluble aerosols on aerosol extinction was $83{\sim}94%$ due to the high mass fraction of these particles in the range of $56{\sim}88%$. Model calculation showed that the water holding capacity of aerosols was larger in Gosan than in Seoul because of higher relative humidity and temperature along with abundant water soluble aerosols. Difference between measured and calculated aerosol optical depths was the highest in summer. This was because aerosol optical depth calculated from ground-based measurements could not consider aerosol loadings at high altitude in spite of high column-integrated aerosol loadings observed by Sun photometer. Although hygroscopic growth was expected to be dominant in summer, the mass concentration of water soluble aerosols was too low to permit this growth.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.172-177
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• 1993

To extract insoluble proteins from sesame meal residue by microorganism, the sesame meal residue was treated with crude enzyme solution of Bacillus sp. CW-1121. The foaming capacity of salt soluble protein was quite lower than that of water soluble protein and the foaming stability of salt soluble protein decreased abruptly in 10 min., while it sustained for 30 min in case of water soluble protein. Emulsion capacities of all the protein fractions showed minimum value near isoelectric point of protein and salt soluble protein had lower emulsion capacities than that of water soluble protein. The emulsion stability of the protein was relatively stable for 30 min at $80^{\circ}C$. Oil and water absorption capacities of salt soluble protein were higher than those of water soluble protein.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.280-287
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• 2021

Generating electricity by using water in many energy harvesting system is due to their simplicity, sustainability and eco-friendliness. Evaporation-driven moist-electric generators (EMEGs) are an emergent technology and show great potential for harvesting clean energy. In this study, we report a transpiration driven electro kinetic power generator (TEPG) that utilize capillary flow of water in an asymmetrically wetted cotton fabric coated with carbon black. When water droplets encounter this textile EMEG, the water flows spontaneously under capillary action without requiring an external power supply. First carbon black sonicated and dispersed well in three different solvent system such as dimethylformamide (DMF), sodiumdedecylbenzenesulfonate (SDBS-anionic surfactant) and cetyltrimethylammoniumbromide (CTAB-cationic surfactant). A knitted cotton/PET fabric was coated with carbon black by conventional pad method. Cotton/PET fabrics were immersed and stuttered well in these three different systems and then transferred to an autoclave at 120 ℃ for 15 minutes. Cotton/PET fabric treated with carbon black dispersed in DMF solvent generated maximum current up to 5 µA on a small piece of sample (2 µL/min of water can induce constant electric output for more than 286 hours). This study is high value for designing of electric generator to harvest clean energy constantly.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.231-237
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• 2006

Grease barrier food containers are commonly used for packaging of fast food, cooked food, and food in general. Greaseproofing is also used for certificate paper and label paper etc. Different pulp raw materials, due to their different fiber morphology and chemical compositions, produce papers of varying characteristics. We used optical photomicroscopy and fiber analysis data to evaluate fiber morphology and traits under various beating conditions in order to understand which pulp raw materials produced superior greaseproofing property when a fluorinated greaseproofing agent was added internally. The experiment studied 9 species of pulps, including 2 softwood (northern pine and radiata pine) bleached kraft pulps which were beaten to 550 and 350 mL CSF, respectively; 3 hardwoods (eucalypts, acacia, mixed Indonesian hardwoods) bleached kraft pulps which were beaten to 450 and 250 mL CSF, respectively; and nonwood fibers of reed, bagasse, and abaca. A fluorinated greaseproofing chemical at 0.12% dosage with respect to dry pulp was added to each pulp preparation and formed handsheets. A total of 67 sets of handsheets were prepared, and their basis weights, thickness, bulks, opacities, wet opacities, air resistance, water absorption and degrees of greaseproofing were measured for an overall evaluation of pulp and freeness on greaseproofing papers. The experimental fiber length, coarseness and distribution characteristics and the greaseproofing results suggest that softwood pulps (radiate pine > northern pine) were superior to hardwood pulps (eucalypts > acacia > mixed Indonesian hardwoods). The unbeaten pulps gave papers with high porosities and nearly devoid of greaseproofing property. Greaseproofing is proportional to air resistance. Among the nonwood fibers, bagasse had the best greaseproofing property, followed by reed and abaca was the poorest. With regards to waterproofing property, hardwood pulps (mixed Indonesian hardwoods > acacia > eucalypts) were better than softwood pulps (northern pine > radiate pine). Among the Nonwood fibers, reed had the highest waterproofing property, and it was followed by abaca, while bagasse had the poorest waterproofing characteristic. In summary, bleached kraft northern pine, eucalypts and reed pulps were best suited for making greaseproofing papers, Freeness of the pulps should be kept at $200{\sim}280mL$ CSF for optimal performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.524-530
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• 1993

The experiment was carried out to investigate the changes in physicochemical properties of milled rice harvested in different year and stored for four to sixty four months. The fat acidity of milled rice increased sharply from four to sixteen months storage, and after then it was increased slowly to sixty four months. Amylose, magnesium, potassium content, and K/Mg ratio of milled rice were not changed by storage duration. Water absorption rates of milled rice at 21$^{\circ}C$ and 77$^{\circ}C$, and alkali digestion value were increased by longer storage duration. Difference of water absorption rate between rice samples was greater during initial forty minutes after soaking at 21$^{\circ}C$ and with longer the soaking time at 77$^{\circ}C$. Shorter gel length of rice flour was found with prolonged storage duration, while peak, minimum, cool, breakdown and setback viscosity of gelatinized rice flour on amylograph were increased along with increasing the storage duration. The volume expansion rate during cooking and degree of iodine coloration of cooking water were higher in the longer stored rice compared with shorter one, and the amount of soluble solid in cooking water was significantly decreased in rice stored longer period.

• Korean Journal of Materials Research
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• v.13 no.3
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• pp.185-190
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• 2003

Titanium dioxide films were prepared by RF sputtering method on glass for various oxygen partial pressures at power 270 W. The crystal structure, photocatalytic property and the hydrophilicity of $TiO_2$thin film the deposition conditions were investigated. Crystallized anatase phase was observed in $TiO_2$film deposited at the ratio of oxygen partial pressure 10% and 20% for 2 hrs. As the increase of deposition time, the grain size and void size of $TiO_2$film have increased and also $V_2$films have been good crystallinity. The ultraviolet-visible light absorption of $TiO_2$films was increased with increasing of deposition time and occured chiefly at the wavelength between 280 and 340 nm. The absorption band was shifted to a longer wave length as deposition time increased. Water contact angle on the X$TiO_2$film of anatase structure was decreased with increasing ultraviolet illumination time and became lower than $11^{\circ}$ from $83^{\circ}$. When hydrophilic $TiO_2$film changed by enough ultraviolet illumination was stored in the dark, the film surface gradually turned to hydrophobic state.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.136-144
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• 1996

Polyacrylic super absorbent polymer(SAP) containing sorbitol was synthesized by inverse-suspension polymerization method. Sodium acrylate and acrylic acid were used as a monomer, ethylene glycol dimethacrylate(EGDMA) and glycerol polyglycidyl ether(GPGE) were used as a crosslinking agent, potassium persulfate(PPS) was used as an initiator, and cyclohexane was used as a solvent. Content of sorbitol was from 10mol% to 50mol% according to the mol ratio of acrylic acid monomer. The size distribution of the round shaped polymeric particle was $177{\sim}707{\mu}m$. Absorption amount of the polymer containing sorbitol was 785 to 1086 times of the polymer weight in distilled water, was 50 to 83 times in 0.9 % NaCl solution. Absorption and retention amount of the polymer were decreased with increasing the amount of sorbitol, but the polymer has an endothermic property which is +5 cal/g SAP.