• Applied Chemistry for Engineering
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• v.3 no.1
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• pp.119-129
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• 1992

The rates of mass transfer with the alkaline hydrolysis of ethyl acetate and n-butyl acetate were measured by using a modified Lewis cell. The rates of mass transfer with chemical reaction were independent of the speed of agitation, and the reaction enhancement factors were independent of the ionic strength. The second order reaction rate constants of ethyl acetate and n-butyl acetate could be obtained from an approximate solution of a diffusion equation by film theory, and their values were $0.041m^3/kg\;mol{\cdot}s$ and $0.338m^3/kgmol{\cdot}s$, respectively.

• Resources Recycling
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• v.11 no.2
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• pp.14-19
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• 2002

PVC sheet was treated in O~10M NaOH solutions at $80~150^{\circ}C$ for O~7 hour, in order to study the leaching phenomena of plasticizer. The yield of phthalic acid produced by hydrolysis of DOP was increased greatly with increasing temperature and NaOH concentration by accelerating of alkali catalyst. The yield of phthalic acid was reached ca. 100% in 10M NaOH at $150^{\circ}C$ over 3 hours. Therefore, the plasticizer containing 30% in PVC sheet could be hydrolyzed in alkali solutions before the occurrence of dehydrochlorination. Besides, in the thermal reaction, the pores were produced in the PVCsheet by the hydrolysis of DOP.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.9-14
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• 1994

알카리금속염 (K$_2$CO$_3$, $K_2$SO$_4$). 알카리 토금속염 (Ba(NO$_3$)$_2$), 철족금속염(Ni(NO$_3$)$_2$, FeSO$_4$) 으로 이루어진 여러가지 혼합물들이 반응온도 700~85$0^{\circ}C$ 하의 촤-수증기 가스화반응에서 나타내는 촉매활성을 열천칭 반응기를 사용하여 측정하였다. 비촉매 가스화반응에서 초기반응성은 수증기 분압에 비례하였다. 촉매 가스화반응에서 단일염 촉매의 경우 $K_2$CO$_3$ 가 가장 큰 활성을 나타내었으며, 다른 염들은 낮은 활성을 보였다. 혼합염의 경우 $K_2$SO$_4$에 철족염을 부가함에 따라 반응속도가 향상되었으며, $K_2$SO$_4$+Ni(NO$_3$)$_2$가 가장 큰 촉매활성을 나타내었다. $K_2$SO$_4$와 Ni(NO$_3$)$_2$ 의 촉매 활성은 담지량에 따라 증가하며, 석탄의 등급에 따라 감소하였다. $K_2$SO$_4$와 Ni(NO$_3$)$_2$의 혼합비는 같은 몰비로 혼합하였을때 가장 큰 활성을 나타내었다.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.175-178
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• 1984

The effects of the addition of starch, salt and soda ash to the dough for Naengmyon (wheat-sweet potato starch) on the mechanical property of Naengmyon noodle were evaluated by using creep test. The strain measurement was made by taking photograph with VTR system. The creep curve of noodle strand could be fitted to the 4 element Burgers model. The instantaneous elasticity and Newtonian viscosity of the noodle strand decreased by the addition of starch. The instantaneous elasticity decreased by the addition of salt up to 4%. The mechamical parameters of the noodle varied inconsistently by the addition of soda ash.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.462-466
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• 2023

After treating spent coffee grounds with alkali, extracts were prepared by using Viscozyme and Alcalase, respectively. Treatment of spent coffee grounds with alkali and enzymes increased the content of phenolic compounds in the extracts, thus possessing the good scavenging activities on free and cation radicals. In particular, the extract obtained by continuous treatment with alkali and Alcalase on spent coffee grounds had the best content of phenolic compounds and antioxidant activity, and inhibited the growth of Streptococcus mutans in proportion to the concentration. In conclusion, the Alcalase-enzymatic hydrolysate of alkali-treated spent coffee grounds showed excellent antioxidant and anticariogenic effects.

• Journal of the Korean Society of Food Culture
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• v.13 no.4
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• pp.261-266
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• 1998

In an attempt to evaluate the effects of alkali agents on properties of Ramyon, cooking quality, textural and sensory properties were examined. The shear extrusion force of Ramyon made from sample A(potassium carbonate 64%, sodium carbonate 14%, sodium pyrophosphate 2% and sodium metaphosphate 20%), sample B(potassium carbonate 31%, sodium carbonate 39% , sodium pyrophosphate 1%, sodium metaphosphate 15%, sodium polyphosphate 8%, sodium phosphate monobasic 4% and sodium phosphate dibasic 2%), sample C(potassium carbonate 60%, sodium carbonate 33% and sodium pyrophosphate 7%), and sample D(potassium carbonate 44%, sodium carbonate 27%, sodium metaphosphate 27% and sodium polyphosphate 2%) were 12.80(kgf), 10.35(kgf), 9.05(kgf) and 8.45(kgf), respectively, but that of control I was 5.24(kgf). The hardness of Ramyon manufactured with sample A, B, C and D were 18.57(kgf), 16.48(kgf), 14.26(kgf) and 12.34(kgf), respectively, but that of control I was 11.23(kgf). At cooking quality examination of Ramyon made from several alkali agents, weight of cooked Ramyon was increased but volume was appeared in vice versa. Extraction amounts of Ramyon manufactured with several alkali agents during cooking were from 35% to 38%, but that of control I was 70%. These changes will provided many advantages in the preparation of Ramyon. The $I_2$ reaction value(${\alpha}-degree$ of noodle) of Ramyon manufactured with several alkali agents and control were shown to almost same values, from 2.10 to 2.20. Sensory properties of cooked Ramyon which was manufactured with several alkali agents showed quite acceptable.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.2
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• pp.114-119
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• 2013

The present study tested 5 concrete mixes to develop reliable mixing proportions for the sustainable alkali-activated(AA) foamed concrete as a thermal insulation material for the floor heating system of buildings. The AA binder used was composed of 73.5% ground granulated blast-furnace slag, 15% fly ash, 5% calcium hydroxide, and 6.5% sodium silicate. As a main variable, the unit binder content varied from $325kg/m^3$ to $425kg/m^3$ at a space of $25kg/m^3$. The test results revealed that AA foamed concrete has considerable potential for practical applications when the unit binder content is close to $375kg/m^3$, which achieves the minimum quality requirements specified in KS F 4039 and ensures economic efficiency. In addition, lifecycle assessment demonstrated the reduction in the environmental impact profiles of all specimens relative to typical ordinary portland cement foamed concrete as follows: 99% for photochemical oxidation potential, 87~89% for global warming potential, 78~82% for abiotic depletion, and 70~75% for both acidification potential and human toxicity.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.247-250
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• 1992

Effects of free alkali and moisture on sucrose polyesters (SPE)-possible non calorie fat substitute-synthesis were investigated using a model system composed of sodium oleate, sucrose, potassium carbonate and methyl oleate. Trace amounts of free alkali in sodium oleate were found to interefere with SPE synthesis. When free alkali content in sodium oleate was varied gradually from 0% to 5%(w/w), the yield of SPE production was reduced from 92% to 45.5%. The moisture absorbed in sodium oleate, sucrose and potassium carbonate during storage also interefered with SPE synthesis. The yield (92%) of SPE production with dried ($105^{\circ}C$.6 hrs) reactants and catalysts was higher than that (89%) of SPE production with non-dried. Soybean oil fatty acid sodium soaps (FASS) not containing free alkali could be manufactured with slightly less than molar ratio of sodium hydroxide to soybean oil fatty acid methyl esters (FAME). Practically, 91.7% yield of soybean oil SPE production was outcomed by minimizing free alkali and moisture which were remaining in sucrose, potassium carbonate, soybean oil FASS and soybean oil FAME.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.508-513
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• 2000

In an attempt to evaluate the fertilizer of sediments obtained from coastal farming areas, chemical composition, bacteriological quality and heavy metals in the sediments alkalized by quicklime and magnesium hydroxide were analyzed. The optimum conditions of alkalization were also measured. A perfect reaction was possible by the addition of quicklime of $30{\%}$ at the rate of $25{\%}$ of sediment and $100{\%}$ of livestock wastes. According to the classification standard for compost constituent by Higgins, all composts had the intermediate or high grade in $T-N, K_2O,\;CaO\;and\;MgO$, but below the low grade in $P_2O_5$, Stabilization by quicklime and magnesium hydroxide has been known to inhibit bacterial decomposition of organic matter and activity of pathogenic organisms. In this study, raising pH of stabilized sediments to 12 for 2 hours (PSRP rriteria of EPA) allowed $99.9{\%}$ of coliform group, fecal group and viable cell count to be reduced. As a result, sediments of coastal farming areas are likely to be used to produce the organic fertilizer by alkaline stabilization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.146-149
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• 1983

An experiment was made to investigate the effect of acid and alkali treatments obfserving the amount of nutrients especially calcium(Ca), phosphorus(P), ${\alpha}$-amino nitrogen(${\alpha}$-amino N), and total nitrogen(total-N)which were extracted from beef bone. 0~0.8% acetic acid and 0~0.5% sodium bicarbonate were used for treatment on different levels. The results are as follows; In case of acid treatment, Ca and P contents in bone stock wer observed to increase significantly according to acid concentration. Ca and P contents in bone stock highly incrased especially when the acid concentration was above 0.3%. Ca and P ratio varied from one to two when the acid concentration was below 0.01%. However contents of ${\alpha}$-amino N and total-N increased significantly when acid concentration was above 0.5%. In case of alkali treatment, contents of Ca and P did not increased significantly on all levels of sodium bicarbonate. The content of ${\alpha}$-amino N, however, increased significantly when the alkali concentration was in 0.05% but total-N did not show any variation in amount. These results suggest that acid treatment can give rise to an increase of the amount of nutrients which are extracted from beef bone but alkali treatment does not.