• Resources Recycling
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• v.19 no.6
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• pp.70-76
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• 2010

It was to investigate the optimum leaching conditions for the NaOH hot digestion and hydrochloric acid leaching of Monazite. The optimum condition for NaOH hot digestion was that the concentration of NaOH/TREO mole ratio was 15, the temperature of decomposition $140^{\circ}C$, and reaction time 2 hrs. And the optimum condition for the hydrochloric acid leaching of NaOH hot digestion product was that the concentration of hydrochloric acid was 6N, leaching time 2 hrs and pulp density about 15%. The yield of rare earth oxide was above 90% on the above experimental condition.

• 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.

• 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 Science and Nutrition
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• v.11 no.4
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• pp.13-16
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• 1982

The hydrolytic conversion of sawdust was studied by sulfuric acid-enzymatic and sodium hydroxide-enzymatic treatments. Sugars were identified by paper chromatography and quantified colorimetrically. Sawdust yielded dextrose and xylose in concentrations ranging from 3.01 to 3.64 and 3.48 to 6.61 grams per 100g. Under optimum conditions, the total concentration of sugars was 10.7 grams per 100 grams.

• 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.

• Mineral and Industry
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• v.23
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• pp.26-31
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• 2010

희토류 정광으로부터 첨단산업 원료소재로 수요가 급증하고 있는 고순도 희토류 소재를 제조하기 위한 가장 첫 공정은 침출공정이다. 즉, 희토류 정광으로부터 원소별 희토류 성분을 분리하기 위해서는 용액상태로 전환이 필요한데, 이때 일반적인 산 및 알카리 용액에는 희토류 성분은 침출이 되지 않으므로 강산 또는 강 알카리 조건에서 희토류 정광을 침출 가능한 형태로 변환 시켜주는 분해공정이 선행되며 이후 산 침출에 의해 희토류 성분을 침출하게 된다. 본 고에서는 대표적인 희토류 광물인 모나자이트와 바스트나사이트, 그리고 이 광물의 혼합물 형태로 생산되는 혼합광물에 대한 분해 및 침출공정을 소개하고자 한다.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1974.06a
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• pp.124.2-124
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• 1974

전보에서 분리ㆍ등정한 섬유소 분해력이 강한 세균을 이용하여 볏짚에서 단세포단백을 생산할 목적으로 각종 알카리에 의한 볏짚의 전처리 효과를 살펴보았다. 즉, 규정농도의 알카리 용액에 24시간 실온에서 침지하여 중성이 될때까지 수세하고 건조시켜 무기염 용액에 4％첨가하여 5일간 진탕 배양한 후 균체량 증가 및 기질의 감소를 측정하여 다음과 같은 결과를 얻었다.(중략)

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.313-318
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• 1984

Some chemical, biochemical and physical treatments on the baker's yeasts (Saccharomyces cerevisiae) before 12-hour digestion at $50^{\circ}C$ were made to accelerate their autolysis. Dilute alkali treatment with 0.01N-NaOH solution showed a considerable increase in soluble nitrogen extraction only in the 6-hour initial autolysis. The addition of fresh yeast autolysate, 10% to the yeast slurry, could increase the autolysis rate from 65% to 83%. Microwave treatment of yeast slurry for 40 seconds also raised the autolysis rate by about 15%, while longer exposures to the microwave accompanying high temperatures repressed the autolysis process. Extrusion of the yeast cells with high pressures of 16,000 to 20,000 psi brought about significantly higher autolysis rate until the digestion time of 9 hours, but thereafter it showed a gradual drop in soluble nitrogen extraction.

• Proceedings of the Korean Printing Society Conference
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• 2001.06a
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• pp.46-60
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• 2001

본 연구는 전기화학적으로 제조된 초환원수 수용액을 탈묵에 적용하기 위한 연구로서 수용액의 알카리도가 고지의 젖음성에 미치는 영향과 그에 따른 탈묵성에 미치는 영향을 고찰한 것이다. 초 환원수는 고전압 하에서 순수 물을 전기적으로 분해한 것으로서 양극에서 pH가 약 11이상의 것을 얻어 사용하였다. 물의 알칼리도에 따라서 탈묵제가 펄플에 젖음성의 영향을 살펴보았으며, 특히 펄프 입자의 표면 전하에 큰 영향을 미쳤다. 이에 따라서 잉크 입자의 탈착이 효과적으로 진행됨이 관찰되었으며, 탈착된 잉크 입자의 크기도 탈묵에 적절함으로서 탈묵 효과가 향상되었다. 이러한 현상을 사용된 계면활성제, 물의 알카리도, 펄프 및 잉크의 표면 전화, 친수/소수화도 등과 비교 검토하였다.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.2
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• pp.47-56
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• 1997

To examine of possibility protein recycling of shaving scraps contained chrome generated from manufacturing process of leather, the characteristics of hydrolyzed protein that differently treated with MgO as alkaline agent were investigated. In alkaline hydrolysis of saving scraps treated with MgO, MgO had to be treated over 5.0% to maintain over pH 8.0 that is insoluble of chrome. Under the condition of alkaline treated with MgO, the solubility of chrome is low with about 60%. The average molecular weight of hydrolyzed proteins from shaving scraps treated with MgO was about 80~100 KD. The amino acid contents of that were largely collagen proteins such as glycine, alanine and proline, and acidic amino acids such as aspartic acid and glutatamic acid. The contents of Mg, Ca and Na in hydrolyzed protein were too much as liquid fertilizer, and chrome contents was 30~40 ppm that largely decreased in comparing with raw materials (40,000~42,000 ppm).