• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.180-185
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were compared for their thermal stabilities at $150^{\circ}C$ and $180^{\circ}C$, respectively. The acid value gradually increased in ARBO during heating period but increased slowly in ERBO-2 and declined gradually in ERBO-1. The peroxide value was somewhat fluctuated during heating period, and the maximum peroxide value in all samples was 13.3 meq/kg. TBA value was sharply increased for the first 10 hr. heating and slowed down thereafter for all samples but ERBO were intensely colored after the heat treatment. The TG ratio of the oils after 90 hr. heating was not different at $150^{\circ}C$ but ERBO was 2-7% higher ratio of TG than ARBO at $180^{\circ}C$. The oxidative stability of ARBO was twice higher than ERBO according to the result of active oxygen test.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.111-116
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• 2010

The treatment of heavy metal, in the waste ash from incinerator and mine solid waste, by using alkali-soluble acrylic copolymer emulsion, that is effective in the absorption of heavy metal has been studied. It seemed that alkali soluble acrylic copolymer emulsion was very effective in the absorption of Hg, Pb, Cd and Cu in this test. Also, eco-friendly thixotropic grout, using alkali soluble acrylic copolymer emulsion, that is effective in the absorption of heavy metal, for the recycling of waste ash from incinerator and mine solid waste has been tested. It was observed that waste ash could be used as a raw material of eco-friendly thixotropic grout mortar due to the effectiveness of alkali soluble acrylic copolymer emulsion in the fixation of heavy metals including $Cr^{6+}$ from waste ash in this test.

• Journal of Korea Foresty Energy
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• v.18 no.2
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• pp.70-77
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• 1999

The behaviors of alkali swelling in four major Korean woods were examined as a function of concentration cf alkali solution. Density of alkali-treated woods increased highly with increasing alkali concentration in both softwoods and hardwoods. Wood samples swelled in dimension during alkali swelling, and thereafter they shrank highly by water washing and air drying. The air-dried wood samples after alkali treatment showed almost isotropic shrinkage in tangential and radial direction.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.522-527
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• 2009

The principal objective of this study was to assess the effects of various manufacturing conditions of soy sauce containing hydrolyzed vegetable protein (HVP) (HVP-soy sauce) on 3-monochloropropane-1,2-diol (3-MCPD) contents. Various HVP soy sauces were prepared under different conditions of alkaline treatment and retention process. Derivatives of heptafluorobutylimidazole (HFBI) 3-MCPD were determined via GC/MS below $0.010{\mu}g/g$, which was sensitive with a good recovery rate. The quantity of 3-MCPD decreased with the pH and temperature of alkaline treatment, and the time and temperature of the retention process increased. Alkaline treatment at pH 10.0-10.5 and a 72 hr retention process were shown to reduce effectively the 3-MCPD contents of HVP-soy sauces. This result indicates that the manufacturing process, particularly alkaline treatment, and retention process would be critical steps in managing 3-MCPD contents in HVP-soy sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.77-86
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• 1990

The residue after hot water extraction of blue crab, Portunus trituberculata, was hydrolyzed for utilizing the byproducts as seasonings. The acid(5N HCl) hydrolyzates were then neutralized with $Na_2CO_3$, 5N NaOH or 5N NaOH hydrolyzate, while the alkali hydrolyzates (5N NaOH) were also neutralized with 5N HCl or 5N HCl hydrolyzate. The total nitrogen and formol nitrogen contents increased, and the platability of the hydrolyzates was also enhanced by neutralization. The released amino acid contents from the neutralized hydrolyzates with $Na_2CO_3$, 5N NaOH and 5N NaOH hydrolyzate were $2,274mg\%,\;2,105.0mg\%$ and $2,683.5mg\%$, respectively. Amino acid contents from the neutralized hydrolyzates with 5N HCl and 5N HCl hydrolyzate were $1,352.5mg\%$ and $2,498.8mg\%$, respectively. In the decolorization of hydrolyzates using decolorization agent, powdered active carbon showed good decolorizing effect. Powdered active carbon decreased total nitrogen and formol nitrogen contents in direct relationship to the increase in its concentration. The effective concentration of active carbon used as decolorization agent showed as $1\~2\%$ of the crab hydrolyzate. Salt contents could be decreased at 37 brix by desalination method such as the evaporation of the hydrolyzate contents.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.373-378
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• 1996

알칼리 및 알칼리토금속(Cs,Rb,Ba,Sr), 전이감속원소(Zr,Fe,Mo,Ni,Pd,Rh), 란탄족 (La,Y,Nd,Ce,Eu.) 및 MA(Np,Am)등 17개 원소로 구성된 질산매질의 모의 방사성용액에서 옥살산에 의한 란탄족과 MA(Minor Actinide)의 공침전 연구를 수행하였다. 옥살산농도 0.5M에서 질산농도의 영향과 아스코빅산 첨가에 따른 원소들의 침전율이 조사되었다. 각 원소들의 침전율은 질산농도에 따라 약간 감소하였으나 란탄족과 MA는 99%이상 공침전되었다. 아스코빅산이 첨가되는 경우 Pd이 금속으로 환원침전되고 Mo.Fe,Ni.Ba의 경우는 침전율이 10∼20% 감소하는 것으로 나타났으나 기타원소들에 대해서는 영향이 나타나지 않았다. Pd의 환원침전은 질산농도 1.0M미만에서 일어났으며. 아스코빅산 농도가 0.01M∼0.02M 부근에서 최대로 나타났다. 하이드라진이 아스코빅산과 같이 첨가될 때 Pd의 환원침전을 억제하는 역할을 하였다.

• Journal of the Korea Concrete Institute
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• v.20 no.4
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• pp.431-437
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• 2008

The concrete pavement at Seohae Expressway in Korea has suffered from serious distress, only after four to seven years of construction. The deterioration of ASR has seldom been reported per se in Korea, because the aggregate used for the cement concrete has been considered safe against alkali-silica reaction so far. The purpose of this study is to examine the expansion behavior of aggregates of Korea due to alkali-silica reaction by ASTM C 1260 standard method of the accelerated mortar bar test (AMBT), stereo microscopic analysis, scanning electronic microscope (SEM) analysis, and electron dispersive X-ray spectrometer (EDX) analysis. The results are presented as it follows. The accelerated mortar bar test (AMBT) showed that mica granite and felsite of igneous rocks, aroke, red sandstone and shale of sedimentary rocks, slate of metamorphic rock, and dendrite and quartz of mineral rock showed more expansion than 0.1% at 14 days. But, some sedimentary rocks and metamorphic rocks expanded more than 0.1% at 28 days even though they were less than 0.1% at 14 days. The mortar bars, which showed more than occurred 0.1% expansion, resulted in cracking on surface. SEM and EDX analysis confirmed that the white gel was a typical reaction product of ASR. The ASR gel in Korea mainly consisted of Silicate (Si) and Potassium (K) from the cement. The crack in the concrete pavement was caused by ASR. It seems that Korea is no longer safe zone against alkali-silica reaction.

• Korean Journal of Food Science and Technology
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• v.7 no.3
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• pp.109-114
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• 1975

Domestic seaweeds Gracilaria verrucosa collected from coastal areas of Namhae, Wando and Yeosoo, Korea were subjected to the examination of yield and quality of agar prepared according to various pretreatment conditions. In alkali treatment at high temperature, higher alkali concentration for one-hour period at $90^{\circ}C$ gave rise to higher yield of agar. In acid treatment, higher yield was obtained by higher acid concentration and longer treating period. Alkali treatment at room temperature gave rise to a slightly decreased yield at higher alkali concentration and longer treating time. Total nitrogen and crude ash of agar samples were greatly decreased by pretreatments. Jelly strength, gelation ability, gelation point and viscosity of agar samples tended to increase as the alkali-treating condition of seaweed became stronger. It was shown that sulfur content of agar had a high negative correlation with jelly strength of its gel. Various alkali treatments of seaweed at room temperature showed no marked difference in agar quality and did not exhibit any good effect comparable to alkali treatment at high temperature.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.709-716
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• 2009

A Kinetics pathway of oxidation of Cefpodoxime Proxetil by permanganate in alkaline medium at a constant ionic strength has been studied spectrophotometrically. The reaction showed first order kinetics in permanganate ion concentration and an order less than unity in cefpodoxime acid and alkali concentrations. Increasing ionic strength of the medium increase the rate. The oxidation reaction proceeds via an alkali-permanganate species which forms a complex with cefpodoxime acid. The latter decomposes slowly, followed by a fast reaction between a free radical of cefpodoxime acid and another molecule of permanganate to give the products. Investigations of the reaction at different temperatures allowed the determination of activation parameters with respect to the slow step of proposed mechanism and fallows first order kinetics. The proposed mechanism and the derived rate laws are consistent with the observed kinetics.

• Journal of the Korean Wood Science and Technology
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• v.14 no.4
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• pp.40-46
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• 1986

Change of color of woods is a trouble frequently found in decorative wood products. In this paper, studies were carried out on discoloation sensitivities of wood specimens to iron (0.1%, $FeCl_3{\cdot}6H_2O$), alkali (pH12.0, NaOH), acid (pH 1.0 $C_2H_2O_4$) and exposing to sunlight (40 hrs.). Four soft-woods and eleven hard-woods grown in Korea were used in this test. The results obtained were as follows: 1. In iron stain, strong discolored wood species were Larix leptolepis, Quercus mongolica. Zelkova serrata and Prunus yedoensis, and light discolored were Paulownia lomentosa and Pinus rigida. 2. In alkali stain. light discolored wood species were Abies holophylla, Kalopanax pictum, Populus ${\times}$ albaglandulosa, Acer mono, Pinus rigida, Pinus densiflora, Quercus mongolica, Betula platyphylla var. japonica, Prunus yedoensis, Zelkova serrata, Populus euramericana, Pinus koraiensis and Paulownia tomentosa, but there was no wood species of strong discolored compared with the color difference values of other reports. 3. In acid stain, light discolored wood species were Pinus rigida, Paulownia tomentosa. Pinus koraiensis, Quercus mongolica, Kalopanax piclum and Acer mone, but there was no strong discolored species compared with the color difference values of other reports. 4. In exposing to sunlight, strong discolored species were Larix leptolepis, Acer mono, Paulownia tomentosa, Populus euramericana, Pinus densijlora, Robinia pseudoacacia, Abies holophylla, Populus ${\times}$ albaglandulosa, Zelkova serrata, Prunus yedoensis and Pinus rigida, and light discolored was Alnus japonica. In general, it was shown that Korean wood species were susceptible to change of color by exposing to sunlight and iron stain compared with by alkali stain and acid stain.