• 한국자기학회지
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• 제5권6호
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• pp.947-951
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• 1995

페라이트는 높은 자기적 손실을 이용하여 전자파 흡수체로 사용하고 있다. 전자파 흡수체는 미세조직이 균일하고 미세할수록 흡수특성이 향상된다. 유기산염 열분해법으로 합성한 분말을 사용하여 Cu-Ni-Zn 페라이트를 제조하였다. 복소유전율과 복소투자율은 밀도가 높고, 입자의 크기가 미세할수록 상승하였다. 페라이트의 정합두께는 소결온도가 높을수록 얇아졌다. Cu-Ni-Zn 페라이트의 전자파 흡수능은 정합두께가 6.75 mm 일 때 160 MHz 부터 640 MHz 까지의 주파수에서 20dB 이상의 값이엿다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제31회 춘계학술대회
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• pp.99-105
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• 2000

Greases composed of base oil and thickener are widely used in the purpose of lubrication and anti-corrosion of machinery. However, greases are sometimes oxidized and decomposed by heat of friction, and produced organic acid. And the greases leaked out ordinary spot make the concrete structures weaken. In this study, the chemical effects of the greases with the concrete structures were investigated through oxidation reaction under pressure and oxygen, and evaluated by the analysis of TAN, Ca content, FT-IR and XRD of grease and cement powder after the oxidation reaction. As the results, TAN value decreased with the increase of the content of cement because of neutralization of organic acid produced by the oxidation of grease with calcium contained in the cement. The content of calcium linearly increased with the increase of cement due to calcium salt by neutralization of acid. Also, according to XRD results of the cement powder oxidized at 99 $^{\circ}C$, the diffraction peak due to calcium hydroxide decreased in comparison with that at room temperature because of the reaction of calcium and organic acid.

• 한국식품조리과학회지
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• 제16권2호
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• pp.121-127
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• 2000

가정에서 제조된 전통된장의 품질을 비교하기 위하여 일반성분, 유기산, 아미노산 및 지방산 조성을 조사하였다. 1. 된장의 수분, 조단백, 조지방, 적정산도(0.1N NaOH 소비 ml수)및 염도는 각각 평균 57.3%, 11.6%, 8.3%, 11.8 및 13.9%였으며, 특기 적정산도.조단백질과 염도는 시료간에 차이가 많이 나타났다. 아미노산성 질소의 함량은 평균 308.4 mg%로서 202.3∼416.3mg%의 범위로 시료간에 1.3∼2.1배 이상 차이를 나타내는 경우도 있었다. Hunter색차계의 L(명도), a(적색도), b(황색도)값은 각각 평균 37.7, +19.6, +7.5이었으며, 수용성 및 지용성 갈변물질은 각각 평균 흡광도 2.23, 0.39로서 유리 아미노산 함량이 총 아미노산 함량보다 5.7배이상 높았다. 2. 유리 및 구성아미노산의 총 함량은 각각 평균 2908.9, 9,019.3 mg%이었으며, 시료간에 1.8∼6.2배와 1.2∼2.0배의 차이가 나타났다. 가장 많은 아미노산은 glutamic acid로서 각각 576, 1,126mg%였다. 3. 유기산은 lactic acid(평균 326.8 mg%)가 가장 많았는데 시료간에 59.4∼613.4mg%의 범위로 큰 차이를 나타내었다. 총 지방산 중에 linoleic acid의 비율(평균49.24%)이 가장 높았으며, 불포화 지방산은 평균 81.97%였고, 다가불포지방산은 시료간에 51.79∼62.97%의 범위로 차이를 많이 나타내었다.

• 한국수산과학회지
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• 제49권2호
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• pp.101-108
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• 2016

We investigated changes in the physiochemical quality of sailfin sandfish sauces fermented with two kojis during long-term storage at room temperature. Four fish sauces, including a control, were prepared by salt-fermentation with soybean koji (S-koji) or rice koji (R-koji) after autolysis. During storage, for 12 months, the color and levels of amino acids, total volatile base nitrogen (T-VBN) and organic acids but not moisture, salt or total nitrogen levels or pH differed markedly according to fish sauce type. The total nitrogen level was highest in S-koji, but there was no difference in the rate of increase in amino acid levels among the four fish sauces during storage. The T-VBN, of autolysis and S-koji were significantly higher than those of the control and R-koji during the entire storage period (P<0.05). The initial organic acid level did not differ among the four fish sauces, whereas it was notably higher in R-koji than in the other sauces at the end of storage. Hunter L, a and b values decreased in all fish sauces with increasing storage time. In conclusion, soybean koji may enhance the levels of nitrogen compounds as well as T-VBN in fish sauce, while rice koji reduced the formation of excess T-VBN and increased organic acid levels during storage at room temperature.

• 펄프종이기술
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• 제46권3호
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• pp.37-43
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• 2014

Kinetics of holocellulose hydrolysis in concentrated sulfuric acid was analyzed using $^1H$-NMR spectroscopy with different reaction time, temperature and acid concentration in secondary hydrolysis. In this work, reaction condition of secondary hydrolysis was similar to concentrated sulfuric acid process with electrodialysis or simulated moving bed chromatography process for sulfuric acid recycling. By $^1H$-NMR spectroscopy, acid hydrolyzates from higher secondary acid hydrolysis (25-35% acid concentration) was successfully analyzed without any difficulties in neutralization or adsorption of acid hydrolyzate to solid salt. Higher acid concentration, higher temperature and longer reaction time led to more cellulose for glucose conversion but accompanied with glucose to galactose isomerization, glucose to unknown compounds and degradation of glucose to organic acid via furans.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.647-650
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• 2003

In anhydrous organic solvents, the complexes formed between AOT (dodecylbenzene sulfuric acid sodium salt) and hemoproteins, such as hemoglobin, myoglobin, or cytochrome c, displayed remarkably higher activity than the hemoprotein powders to oxidize dibenzothiophene, a model compound of organic sulfurs contained in fossil fuels. In slightly hydrophobic organic solvents, such as ethyl acetate and butyl acetate, dibenzothiophene was completely oxidized catalytically by the cytochrome c-AOT complex with cumene hydroperoxide (${\alpha},{\alpha}-dimethylbenzyl$ hydroperoxide) as an oxidant. In highly hydrophobic organic solvents, such as decane and hexadecane, however, the activity of the cytochrome c-AOT complex decreased, presumably due to the aggregation of the hemoprotein-AOT complex in these solvents.

• 대한화학회지
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• 제9권1호
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• pp.1-7
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• 1965

토루엔, 디메틸폴움아마이드, 디메틸슬포옥사이드, 테트라하이드로퓨란, 아세토나이트라일 및 디옥센 等 溶媒存在下에서 모노클로로醋酸과 亞鉛을 反應시켜 본 結果, 溶媒효果를 나타내었다. 反應試藥의 反應度가 溶媒의 極性 및 親水性에 따라 增加하였다. 같은 溶媒系를 使用하여 에틸모노클로로醋酸을 反應시켜 본 結果, 溶媒효果를 나타냈으나 酸의 境遇보다 그 差가 크지 못하였다. 酸, 에스타, 亞鉛 및 카보닐化合物(벤즈알데히드 및 4-헤프타논)의 反應에 있어서는 알데하이드의 境遇에 있어서는 Reformatsky 反應生成物을 주었으나, 4-헤프타논과의 反應度는 없었다. 反應生成物의 收率은 試藥添加方法에 따라 變化되었다. 最高收率은 酸의 하이드로옥시酸(38.5%), 0.8g의 salt(아세트나이트라일溶媒)이며, 에스타의 境遇에는 에틸신나메이트(19.3%), 폴리머(21.6%)이였다. 카보닐化合物의 境遇에 있어서는 反應溫度에 따라 試藥의 反應度의 變化가 있었다. 硏究結果를 溶媒效果에 關聯시켜 論議하였으며, 硏究方法에 關하여 記述하였다.

• 한국산학기술학회논문지
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• 제10권5호
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• pp.1148-1156
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• 2009

쌀을 주원료로 국수를 제조하기 위해 유기산과 증점제를 이용하고 단백질, 텍스트린, 정제염을 첨가하였다. 혼합 유기산과 증점제를 사용한 쌀가루 반죽의 증숙 후 물성은 최대응력(max weight)은 평균 $2040.00\;g/cm^2$ 이었고 탄성 139.12%, 응집력 66.05%, 씹음성 1,396.13 g, 깨짐성 190,456.12 g으로 나타났다. 이상의 결과 쌀가루를 이용한 쌀국수제조에 적합한 조건은 다음과 같다. 원료쌀의 수침은 $20{\sim}25^{\circ}C$에서 12시간 실시하고 $35^{\circ}C$이하 온도에서 분쇄를 2회 실시하는 것이 적합하였고, 쌀가루의 물성을 변화시키기 위해 혼합유기산 0.255%(무수 구연산 0.10%, 사과산 0.75%, adipic acid 0.03%, 양조식초 0.05%), 혼합 증점제 2.820%(산탄검 1.00%, 구아검 0.80%, 알긴산나트륨 0.96%, 폴리아크릴산나트륨 0.06%), 글루텐 3.00%, 덱스트린 1.00%, 카제인나트륨 1.00%, 정제염 3.88%를 혼합한 쌀가루로 국수를 제조하는 것이 적합한 조건으로 판단되었다.

• 아시안잔디학회지
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• 제5권1호
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• pp.47-53
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• 1991

A laboratory experiment was conducted in order to learn the effect of a number of organic matters on the ammonification and nitrification of urea, and the reaction of soil, applied to a loamy upland soil poor in orgnic matter(<1.5%, without plants 1.The ammonification of urea was most pronounced in one week period immediatly after fertilizer and water treated, after which a rapid decrease of it was followed showing no accumulation at the end of 3rd week. Owing to the accumlation of ammonium, pHs of treated soils were read 7.0 to 7.3 from 6.8~6.9. 2.Nitrification was also progressed rapidly in the first one week period so that the accumulation of NO$_3$-N surpassed that of ammonia during this period. After the 1st week the accumulation of N0$_3$-N was continuously increased showing the maximum at the end of 4 weeks following a sharp decrease at the end of 5th weeks. The accumulation of NO$_3$-N dropped soil pH from 6.8-7.0 to 6. 0-6.2,but the decrease of NO-N at the end of 5th weeks brought up soil pH to 6.4-6.6. again. 3.Amino acid fermentation byproduct rich in salt, paticularly chloride, slowed down the ammonification and nitrification of urea. 4.The application of organic matter diminished the acidifying effect of chemical fertilizers. The diminishing effect of soluble humic acid and amion acid fermentation byproduct showed greater than that of solid organic matter in this experiment, which might be own to the application of a rather small amount of water soluble organic matters. Rice straw powder among solid organic matters appeared to be the least in the diminishing effect above. It may be reasoned that these soluble organic matters decomposes rapidly so as to affect Soil pH, but solid organic matters, particularly the rice straw powder, form acidic humus.

• 한국응용과학기술학회지
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• 제30권3호
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• pp.504-517
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• 2013

The purpose of this study was to process extraction and separation for polyglucose porpyran from pophyra yezoensis as high yield. The acidic porphyran solution was extracted with 0.1~1N of ${\alpha},{\beta}$-dichloromaleic acid or ${\alpha}$-chloromaleic acid of 2% solution as organic acid instead of inorganic acid at $60^{\circ}C$ and then porphyran was collection of high yield to acidic solution and it was neutralization treated with 0.1N of $d-Ca(OH)_2$ solution and the mixture was conversion to porphyran salt form and treated with a shell powder of ouster and then added of ethanol as precipitator. It recovery porphyran contained of violet purple laver coloring matter was obtained as a crystalline and used for the next step without future purification to prepare of porphyran laver jam. so, The resulting porphyran and porphyran jam was characterized by it component and physical properties.