• Membrane Journal
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• v.32 no.2
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• pp.109-115
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• 2022

In this work, the effect of nonwoven support during fabrication of flat sheet membranes via nonsolvent-induced phase separation, was investigated in detail. It was found that dope solutions with low viscosity tend to penetrate through the nonwoven support during phase inversion, resulting in nonhomogeneous membranes. A simple soaking treatment of nonwoven support prevented such unwanted dope penetration, and resulted in membranes with higher water and solvent permeance performance. The dope penetration through nonwoven was more prominent in solutions with low viscosity, and the nonwoven soaking treatment not effective in solutions with high viscosity.

• Journal of Adhesion and Interface
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• v.20 no.3
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• pp.87-95
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• 2019

In the present study, the effect of alkali treatment of rice straw on the flexural properties and impact strength of rice straw/recycled polyethylene composite was investigated. Alkali treatments were performed by means of two different methods at various sodium hydroxide (NaOH) concentrations. One is static soaking method and the other is dynamic shaking method. The composites were made by compression molding technique using rice straw/recycled polyethylene pellets produced by twin-screw extrusion process. The result strongly depends on the alkali treatment method and concentration. The shaking method done with a low concentration of 1 wt% NaOH exhibits the highest flexural and impact properties whereas the soaking method done with a high concentration of 10 wt% NaOH exhibits the highest properties, being supported qualitatively by the fiber-matrix interfacial bonding of the composites. The properties between the two highest property cases above-described are comparable each other. The study suggests that such a low concentration of 1 wt% NaOH may be used for alkali treatment of natural fibers to improve the flexural and impact properties of resulting composites, rather than using high concentrations of NaOH, 10 wt% or higher. Considering of environmental concerns of alkali treatment, the shaking method is preferable to use.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.85-94
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• 1988

This experiment was carried out to obtain the basic data for removal the astringency and off-flavor in soybean milk, by means of soaking of soybean in NaOH and $NaHCO_3$ solutions. The changes of phenolic compounds in soybean during soaking were investigated with HPLC and also the changes of flavor and sensority of soybean milk, prepared from soaked soybean were studied. Phenolic compounds of soybean were identified as chlorogenic, p-hydroxybenzoic, p-coumaric, ferulic and gentisic acid and, chlorogenic acid content was greater than the others. The chlorogenic acid of soybean was mainly neutral type and the other compounds were almost acidic type. Up to 85% of the chlorogenic acid was removed by soaking of soybean in 0.1% of NaOH solution for 8 hrs. Phenolic compounds of soybean was almost removed by soaking in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr. Chemical composition of soybean milks prepared from soaking of soybean in water, 0.1% NaOH and 0.5% $NaHCO_3$ solution were similar. Hexanol content of beany flavor in soybean milk was increased by soaking of soybean in NaOH solution, where as hexanal, propanal, pentanal contents were removed up to 60%. Color of soybean prepared from soaking of soybean in NaOH solution at high temperature were deep yellow but were high whiteness in soybean milk prepared from soaking of soybean in water at low temperature. Sensority of soybean milk prepared from soaking of soybean in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr was more favorable than the others.

• The Korean Journal of Mycology
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• v.28 no.2
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• pp.67-72
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• 2000

The purpose of this study was to investigate the change of water content in mushroom substrate, paddy straw, and the mycelial growth of oyster mushroom by various soaking time. The water content of paddy straw was gradually increased as the soaking time was getting longer. These experiments also showed that the water content in the upper part of paddy straw was less than that of the low part. The mycelial growth was the good between 4 and 12 hours soaking treatment, showing faster growth and higher density in the lower part than the upper part. However we could not found any significant variation among 5 strains of oyster mushroom in the effects of the various soaking times and soaking part. The pH of the lower part substrates had a low pH compared with that of the upper part. When pathogens and mushroom mycelia were co-inoculated on paddy straw under various soaking conditions, the mushroom mycelial growth showed fast and high density according to the increase of the soaking time. The experiment related to water transport reveals that it is not easy to move into upper part, but only soaked part by adding water is available to absorb enough water. Old straw was much better than the straw new this year one for water absorption, mycelial growth and mycelial density.

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.132-136
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• 1995

This study was carried out to elucidate the effective of some swelling agents on the soaking treatment of raw silk. The swelling of raw silk is commonly practiced by soaking in warm water, However, it is not enough to weaving of raw silk. Therefore, the combination of some chemical agents were tested to improve the swelling ratio of raw silk. The pretreatment of raw silk in 0.4N sodium carbonate aqueous solution before soaking in the mixed solution of Emulon 1 g/l, Emanol 0.5 g/l and 0.04N sodium silicate increased the swelling ratio by 57%, compared to the nontreatment. In SEM observation, the surface of raw silk soaked in swelling agents was swollen and smoothed.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.381-387
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• 2009

Enhancing enzymatic saccharification of corn stover by aqueous ammonia soaking pretreatment was investigated on chemical compositional changes and enzymatic hydrolysis characteristics. At three different levels of aqueous ammonia soaking temperature and time ($140^{\circ}C$-1 h, $90^{\circ}C$-16 h and $50^{\circ}C$-6 days), higher temperature and shorter treatment time led to more xylan and lignin removal based on overall composition analysis and carbohydrate compositional analysis. More xylan and lignin removal in higher temperature treatment led to higher enzymatic saccharification of cellulose and xylan to monosaccharide by commercial cellulase mixtures (Celluclast 1.5L and Novozym 342 from Novozyme, Denmark).

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.104-108
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• 1993

This experiment was conducted to obtain the basic information for the increase ofgermination percent by the treatment of stratification, soaking and $Gibberellin(GA_3)$ in Angelica gigas Seeds caltivated in 1989. The germination percent was increased by 30% with stratification, and the effect of low temperature did not differ significantly. The optimum soaking temperature and periods were found to be 4days at $20^{\circ}C\;and\;6dys\;l0^{\circ}C$ of water temperature. When exchanged water every day during soaking period, inhibitors were more extracted than non-exchange one. The exogenous application of $GA_3$ also increased germination percent about 20% campared with control, and the reasonable level was 2ppm in soaked seed and 5ppm in non-soaked seed.

• Korean Journal of Medicinal Crop Science
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• v.22 no.1
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• pp.53-59
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• 2014

This study was conducted to determine the effects of seed storage temperature and pre-treatment on seed germination, seedling quality and vigor index of wild Trichosanthes kirilowii and Trichosanthes kirilowii var. japonica. As a result the highest germination rate of T. kirilowii was the 95% at seed stored in room temperature and then soaking for 24 hours in $dH_2O$. And the highest germination rate of T. kirilowii var. japonica was 96% at seed stored in $2^{\circ}C$ and then soaking for 24 hours in $GA_3$ (100 ppm). But the seed germination rate was non-significance in pre-treatment at seed stored in room temperature $2^{\circ}C$. Seedlings of T. kirilowii and T. kirilowii var. japonica showed not only the best seedling quality but also seedling vigor index in seed stored at $2^{\circ}C$ and then soaking for 24 hours in $GA_3$ (100 ppm). In this research, T. kirilowii and T. kirilowii var. japonica seed were stored in room temperature or $2^{\circ}C$, and then sown in peat moss, seed germination rate was more than 90% and production of superior quality seedlings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.297-303
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• 1993

Seedling emergence and .stand establishment in dry-seeded rice is unstable at present due to deep seeding, low temperature at seeding time, excessive drought or raining etc. This experiment was conducted to elucidate the effect of gibberellic acid(GA$_3$) on the seedling emergence and growth in dry-seeded rice. GA$_3$, IBA and Metalaxyl were treated by seed-soaking or-spray. Hwaseongbyeo, a japonica rice, was used. The seed-soaking treatment with GA$_3$ significantly increased the seedling emergence and plant height as compared with untreated seed. However, no difference was observed in IBA and Metalaxyl treatment. The optimum concentration of GA$_3$ to promote the seedling emergence and growth in dry-seeded rice was about 100ppm for seed-soaking and about 200ppm for seed-spray treatment. The seed-spray treatment of GA$_3$ with 200ppm promoted earlier and faster seedling emergence and elongated seedling height as compared with untreated seed.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.30-36
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• 1983

Plywood, the representative interior decorative or structural material, is so inflammable that it may cause big fires. Therefore, it is required inevitably to manufacture the "Fire retardant treated plywood", and it will be a study on the redrying of treated plywood that we ought to solve. This study was carried out to investigate the absorption of 20% $(NH_4)_2HPO_4$ solution into the soaked plywoods by hot/cold soaking for 3/3, 6/3, 9/3 and 12/3 hours and to study drying process with drying curves and drying rates by press-drying at the platen temperature of 130, 145, 160 and $175^{\circ}C$. Solution absorption of plywoods in hot/cold soaking method increased steadily with the prolonged soaking time, and water absorption is higher than DAP absorption, and then chemical retention (DAP) exceeded the minimum retention [$1.125kg/(30cm)^3$] even in the shortest soaking treatment. Drying curves of water-soaked plywoods inclined more steeply than those of DAP soaked plywoods. And the drying proceeded rapidly with the increase in platen temperature and terminated in 2.5-4 minutes at the temperature of 160 and $170^{\circ}C$. Drying rate also increased generally with the increase of platen temperature. So it was at $175^{\circ}C$ in DAP-soaking and at $160^{\circ}C$ in water-soaking when the drying rate became above 10%/min.