• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.1-12
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• 2002

Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.

• Journal of Korean Society of Forest Science
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• v.4 no.1
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• pp.30-32
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• 1965

Many kind tree species are growing in Korea. However most of them are inferior in wood qualities and production for commercial utilization except several species. Among the useful several species Red Pine (Pinus densiflora S. et. Z.) is growing in main tree species and most generally utilizing wood in korean forest. It is used widely as mine timbers, cross ties, boxes, floorings, pulpwoods, constructions and engineerings. Although this species is most useful and economical in this country, the basical properties on relation between wood and relative humidities were not studied certainly. This study was performed by need of inspection the hygroscopic and swelling properties to be apllied for physical manufacturing. According to the results the Equilibrium Moisture Contents of each relative humidity conditions are as table (3), and the swelling values of sap and heartwood are as table (4) and (5) in text. In this study sapwood moisture contents are higher than heartwood in each relative humidities conditions. Tangential and radial ratios of average swelling values are 1:1.971 in sapwood and 1:2.178 in heartwood.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.88-95
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• 2013

Effects of beating and water immersion time on fiber swelling and paper properties were elucidated for the fundamental study of producing high bulk paper. Chemical pulps were beaten for various freeness and the beaten pulp was immersed in water up to 24 hours. Fiber swelling was evaluated by measuring water retention value (WRV). It was found that fiber swelling, bulk and paper strength were quickly changed at the initial stage of beating. Immersion in water did not significantly increase WRV, paper density and strength, implying that soaking in water alone could not effectively swell fiber wall. In order to swell further, hydrogen bonds between fibrils in fiber wall and hence fiber wall structure shall be broken by mechanical force during beating.

• Journal of the Korean Applied Science and Technology
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• v.26 no.3
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• pp.263-268
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• 2009

Superporous Hydrogels (SPHs) have been extensively investigated for various biomedical applications due to their fast swelling and superabsorbent properties. In this study, glycol chitosan that is one of most abundant natural polymers was used as a cross-linking agent instead of bisacrylamide (BIS), which is a broadly used crosslinking agent for preparation of SPHs. Glycol chitosan was modified to have reactive vinyl groups by chemical conjugation with glycidyl methacrylate (GMA). The vinyl group-containing glycol chitosan (GC-GMA) was characterized by FT-IR and $^1H$-NMR measurements. SPHs have been prepared in various synthetic conditions to establish the optimum synthetic process for making superporous structure, where the inner pores are interconnected to each other to form a open channel structure. Various SPHs with different GC-GMA contents have been successfully prepared and have been observed to show faster swelling properties than other conventional SPHs. From the study on the swelling behavior of SPHs, the GC-GMA content is considered to be an important factor for controlling their swelling properties.

• Bulletin of the Korean Chemical Society
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• v.4 no.4
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• pp.162-169
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• 1983

The swelling and stress-elongation experiments have been performed for two kinds of gels of tactic poly (2-hydroxyethyl methacrylate) (P-HEMA) with varying crosslinker concentrations. The gels of isotactic and syndiotactic P-HEMA were swollen in aqueous salt solutions upon varying molal concentrations. The solute used were NaCl, $MgCl_2$, $Na_2SO_4$, $MgSO_4$ and urea. The water content at equilibrium swelling and the salt partition coefficient were determined, and stress-elongation curves of the gels were obtained. From these results, the effective number of chain (${\nu}_e$) and the Flory-Huggins interaction parameter (${\chi}_1$) were also obtained. The swelling experiment was also performed under varying solvents, and the degree of swelling was determined. The solubility parameter of P-HEMA was obtained as 13.4 (cal/mole)$^{l/2}$ using the correlation between the degree of swelling and the solubility parameter (${\delta}_1$) of solvents. The mechanical properties of syndiotactic P-HEMA is stronger than that of isotactic P-HEMA, and the water content of both gels become smaller when the crosslinking increases. Isotactic P-HEMA contains more water content than syndiotactic P-HEMA does.

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.71-78
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• 2004

The purpose of this study was to investigate the water absorption and thickness swelling of biocomposites at room temperature. These properties of bio-composites mainly depend on the ability of the agro-flour to absorb water through hydrogen bonding between water and the hydroxyl groups of the holocellulose and lignin in the cell wall. As the content of agro-flour increased, the water absorption and thickness swelling of the bio-composites increased. The effects of agro-flour content and rice husk flour (RHF) particle size on the water absorption and thickness swelling of the bio-composites were evaluated. In general, wood-based materials showed significantly higher water absorption and thickness swelling than the bio-composites. This might be attributed to the ability of the polybutylene succinate (PBS) hydrophobic polymer to prohibit the water absorption and thickness swelling of the bio-composites, Therefore, the use of agro-flour filled PBS bio-composites, which exhibit improved dimensional stability in comparison with wood-based materials, is recommended.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.207-213
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• 2006

The effects of gellan gum (from S. paucimobilis), EPS-CB (exopolysaccharide from S. chungbukensis), and a series of commercial gums (arabic gum, xanthan gum, guar gum, deacyl gellan gum), on the swelling, rheological, and pasting properties of non-waxy rice flour dispersions were investigated. The swelling properties of rice flours in gellan or guar gum dispersion after heating were found to have increased with increasing gum concentrations, but the swelling properties of rice flour/other gum systems decreased with increasing concentrations. The rice flour/gum mixtures showed high shear-thinning flow behavior (n=0.14-0.32), and consistency index (K) was higher in guar gum than other gum dispersions. The initial pasting temperatures and peak times increased along with increasing gum concentration. The peak viscosity of rice flour increased in guar gum and deacyl gellan dispersions, and the breakdown and setback viscosity of the rice flour paste was lowest in the xanthan gum system, but remained higher than those of the control. The apparent viscosities of the rice flour/gellan gum mixture pastes were the highest among the tested combinations.

• Geomechanics and Engineering
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• v.15 no.6
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• pp.1219-1225
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• 2018

In this study, a comprehensive laboratory experimental programme was conducted on expansive soil with a high swelling potential to study the influence of different additive materials on swelling pressure and index properties. Lime, sand, multifilament fiber and fibrillated fiber were used for stabilization of expansive soil. Lime, sand and fibers were respectively added to the expansive soil at 0-7%, 0-80%, 0-0.5%. On each mixture that was prepared by the proportions mentioned above, Atterberg limits, compaction, and swelling pressure tests were conducted. From the result of these experiments, the swelling pressure-time relation could be replaced by a rectangular hyperbola established to facilitate the prediction of ultimate percent swelling with a few initial data points. The best type of additive and its optimum ratio for engineering purposes could be estimated rapidly by this approach.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2635-2641
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• 2012

Novel silver/salep-g-poly(acrylic acid) nanocomposite hydrogel were prepared in aqueous solution using poly(acrylic acid) grafted onto salep as a biopolymer based material. FT-IR spectra confirmed that poly(acrylic acid) (PAA) had been grafted onto salep in graft copolymerization reaction. TEM observations showed that silver nanoparticles have been uniformly dispersed in polymeric matrix. Effects of pH, acrylic acid (AA) amount and silver ion concentration on swelling capabilities were investigated. Results indicate that modifying AA and silver ion can improve swelling properties of the resultant nanocomposite hydrogel. pH response of this nanocomposite hydrogel in acidic and neutral pH made it suitable for drug delivery applications.

• Journal of Pharmaceutical Investigation
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• v.21 no.2
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• pp.91-95
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• 1991

Polyethylene glycol, polypropylene glycol and block copolymer of ethylene glycol and propylene glycol were crosslinked by triisocyanate to form water swellable, rubbery polymer. The equilibrium swelling of the hydrogels ranged from 3% to 60% according to the hydrophobic-hydrophilic properties of the prepolymers. Model drugs, sodium salicylate and prednisolone were incorporated in the polymer matrices by swelling loading. Physical properties of the drugs affected the drug release mechanisms due to the change in the swelling behaviors of the polymeric devices. Zero order release was observed in the case of relatively hydrophobic polymer matrices.