• Title/Summary/Keyword: Acid-

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Studies on Slip and Mechanical Properties of Thermoplastic Polyurethane Elastomer Containing Sulfuric Acid (Sulfuric acid를 도입한 열가소성 폴리우레탄 탄성체의 슬립특성 및 기계적 물성에 관한 연구)

  • Mok, Dong Youb;Shin, Hyun Deung;Kim, Dong Ho;Kim, Gu Ni;Kim, In-Soo
    • Elastomers and Composites
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    • v.48 no.4
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    • pp.256-262
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    • 2013
  • We synthesized thermoplastic polyurethane elastomer (TPU) with different contents of sulfuric acid group, and characterized their physical properties such as mechanical, thermal and grip properties. And the results were compared with carboxylic acid-introduced TPU. Wet slip, tensile strength and abrasion properties were increased by the introduction of acid group. Mechanical properties increased with increasing the acid content up to 0.3 wt%. However, wet slip was continually increased as the acid content increased due to increase of hydrophilicity of TPU.

Reactive Extraction of Succinic Acid by Amino Extractants and Comparison of Extraction Characteristics of Maleic Acid (아민계 추출제를 이용한 숙신산의 반응추출 및 말산과의 추출특성 비교)

  • 홍원희;홍연기
    • KSBB Journal
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    • v.19 no.1
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    • pp.33-37
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    • 2004
  • Succinic acid is of interested as the raw material of biodegradable polymer. In this study, succinic acid was separated by reactive extraction using amine extractants such as TOA (trioctylamine) and Aliquat 336. The extractability of TOA for succinic acid was higher than that of Aliquat 336. The distribution of succinic acid into organic phase was decreased with increasing pH in aqueous phase. However, the effect of pH on the extractability of Aliquat 336 was little. In the case of maleic acid which has similar structure to succinic acid, the extractability for maleic acid was higher than that for succinic acid. It was mainly due to the difficulty of deprotonation of second carboxylic group by intramolecular hydrogen bonding.

Effective Components on the Taste of Ordinary Korean Soy Sauce (한국재래식 간장의 맛에 영향을 미치는 성분)

  • 김종규;정영건;양성호
    • Microbiology and Biotechnology Letters
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    • v.13 no.3
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    • pp.285-287
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    • 1985
  • To investigate effective constituents of the many taste components in ordinary Korean soy sauce, we analyzed free amino acids, organic acids, free sugars and saline as taste components in ordinary Korean soy sauce, and determined sensory score of the ordinary Korean soy sauce taste with 45 persons of the trained pannels. The relationships between original data transformed with variables and sensory score of the ordinary Korean soy sauce were analyzed by stepwise multiple regression analysis. Eighty five percents of the ordinary Korean soy sauce taste is affected by twenty one kinds (Isoleucine, Leucine, Valine, NaCl, Lactic acid, Alanine, Phenylalanine, Tartaric acid, Sugar(\ulcorner), Proline, Malic acid, Glycine, Tryptophan, Arginine, Glutaric acid, Maltose, Histidine, Glucose, Fructose and Serine) of the taste components by stepwise multiple regression analysis of original data. Eighty one percents of the ordinary Korean soy sance taste is affected by sixteen kinds (Lactic acid, NaCl, Fumaric.Succinic acid, Tyrosine, Tartaric acid, Glycine, Malonic acid, Malic acid, Tryptophan, Glutaric acid, Methionine, Histidine, Cysteine, Maltose, Fructose and (Glutamic acid) of the taste components by stepwise multiple frgression analysis of original data transformed with square root. Eighty five percents of the ordinary Korean soy sauce taste is affected by nineteen kinds (Fumaric.Succinic acid, Lactic acid, Phenylalanine, NaCl, Tyrosine, Sugar(\ulcorner), Tartaric acid, Leucine, Glutaric acid, Methionine, Glycine, Tryptophan, Histidine, Proline, Cysteine, Glutamic acid, Maltose, Threonine and Oxalic acid) of the taste components by stepwise multiple regression analysis of original data transformed with logarithm.

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Protective Effects of the Phenolic Compounds from the Leaves of Hedera rhombea on Hepatic Injury (송악의 페놀성 물질의 간 보호효과)

  • 김경숙;송지영;이인란
    • YAKHAK HOEJI
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    • v.43 no.4
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    • pp.516-525
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    • 1999
  • Hedera rhombea (HR) has been used for treatments of hemorrage, chronic catarrh, jaundice, lithisis and convulsion. This study was done to isolate active compounds that have protective effect on liver damage. BuOH and EtOAc fractions of HR recovered serum glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) and ${\gamma}-glutamyltranspeptidase$ (${\gamma}-GTP$) activities in CCl4 treated rats. We isolated 7 phenolic compounds from BuOH and EtOAc fractions, which were identified as 3-caffeoyl quinic acid, 3,4-di-O-caffeoyl quinic acid, 3,5-di-O-caffeoyl quinic acid, 4,5-di-O-caffeoyl quinic acid, caffeic acid, methyl 3,4-di-O-caffeoyl quinic acid and methyl 3,5-di-O-caffeoyl quinic acid by chemical and spectral analysis. These compounds reduced significantly serum GOT and GPT elevated by CCl4 treatment in rats, and 3-caffeoyl quinic acid, 3,5-di-O-caffeoyl quinic acid and caffeic acid also showed mild inhibitory activity against human immunodeficiency virus.

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Synthesis of DL-Aminoalkyl Phosphonic Acids and Their Derivatives (III) (DL-Aminoalkyl Phosphonic Acid와 그 유도체들의 합성 (제3보))

  • Man Khyun Rho;Yong Joon Kim
    • Journal of the Korean Chemical Society
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    • v.17 no.2
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    • pp.136-141
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    • 1973
  • DL-1-aminobutylphosphonic acid was synthesized from the pentanoic acid which was prepared from the butyl alcohol, by the modified Curtius reaction. DL-2-amino-2-carboxyethylphosphonic acid was also synthesized from the pyruvic acid was also synthesized from the pyruvic acid. Four previously unreported N-acylated derivatives were prepared according to the modified Schotten-Baumann method. They are as follows; N-acetyl-DL-1-aminobutylphosphonic acid, N-benzoyl-DL-1-aminobutylphosphonic acid, N-benzoyl-DL-2-amino-2-carboxyethylphosphonic acid, N-p-chlorobenzoyl-DL-2-amino-2-carboxyethylphosphonic acid. The products were identified by the methods of elemental analysis, infrared spectra, ninhydrin test and neutralization equivalent.

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Effects of Organic Acids on Korean Naeng Myon Broth (유기산의 첨가가 냉면육수에 미치는 영향)

  • 오혁수;안승근
    • Culinary science and hospitality research
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    • v.4
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    • pp.413-436
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    • 1998
  • In order to guarantee the safety of Korean Naeng Myon Broth in summer, pH and micrological quality of iced noodle gravy which is cooked and sold in public restaurant were investigated. And the variations of pH, taste and microorganism were studied with organic acid treatment during storage period. The micrological status of iced noodle gravy showed that average number of total aerobic bacteria was 2.7${\times}$105CFU/$m\ell$ and fecal coliform was 8.3${\times}$103CFU/$m\ell$ respectly. Food poison microorganisms not detected and average of pH was 4.8. pH changed slightly during storage period and deceased with increasement of organic acid added. Sour taste of organic acid increased acetic acid, citric acid, lactic acid order and there was no organic acid having with more sour taste than iced noodle gravy which is cooked and sold in public restaurant. Salmonella was destroyed when treated with 1% of acetic acid and lactic acid and Escherichia coli became extinct at treatment with 0.8% acetic acid and 1% lactic acid. in case of same concentration, inhibition effects to Escherichia coli multiplication show citric acid, lactic acid, acetic acid order. In conclusion, treatment with more than 0.8% acetic acid and above 1.0% lactic acid or more than 1.0% citric acid in case of production and consumption a day can prevent from Escherichia coli pollution in Korean Naeng Myon Broth.

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Improvement of Ethanol Yield by Addition of Acetic Acid and Acetatdehyde in Ethanol Fermentation (에탄올 발효에서 초산 및 아세트알데히드 첨가에 의한 에탄올 수율의 증진)

  • 김진현;여주상유영제
    • KSBB Journal
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    • v.10 no.4
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    • pp.370-373
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    • 1995
  • The major by-products in ethanol fermentation by Saccharomyces cerevisiae were glycerol, acetaldehyde, acetic acid, lactic acid, and formic acid. The effects of these by-products on the cell growth and ethanol production were studied. By adding acetaldehyde or acetic acid in the fermentation broth, the cell growth decreased while the ethanol production increased. But glycerol and lactic acid had nearly no effects on the cell growth and the ethanol production. Acetic acid and acetaldehyde inhibited the cell growth by diminishing the growth rate as well as by prolonging the lag phase. The ethanol yield increased with the elevation of concentrations of acetic acid and acetaldehyde in the fermentation broth. The maximum ethanol yield was obtained for $3g/\ell$ acetic acid and $2g/\ell$ acetaldehyde, respectively.

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Effect of Cultural Conditions on the Lipid Production by Moulds (곰팡이 유지 생산에 관한 배양조건의 영향)

  • 손병효;정태명;김용균;최상욱
    • Korean Journal of Microbiology
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    • v.23 no.4
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    • pp.252-258
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    • 1985
  • Aspergillus niger var. macrospours, Aspergillus fumigatus, Penicillium notatum and Penicillium spinulosum were cultured under different cultural conditions. The lipids produced by these species and fatty acid compositions of lipids were investigated. The macimum lipid contents produced by each species were 17.8% for Asp. niger var. macrosporus, 31% for Asp. fumigatus, 12.6% for P. notatum and 17.5% for P. spinulosum, respectively. The major fatty acid compositions were palmitic acid, stearic acid, oleic acid and linoleic acid. Asp. niger var. macrosporus and Asp. fumigatus were highest oleic acid during all incubation periods and P. notatum and P. spinulsum were linoleic acid. Degree of unsaturation was higher Penicillium than Aspergillus. The fatty acid compositions were changed depending on the incubation temperature, but hardly showed a certain tendency except linoleic acid and degree of unsaturation that were higher at lower temperature.

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The Comparative Studies for the Anti-stress Effect of Guibitang and Ascorbic Acid on Heating and Swimming Stress (열(熱)Stress 및 유영(游泳)Stress에 대(對)한 귀비탕(歸脾湯)과 Ascorbic Acid의 항(抗)Stress효능(效能) 비교연구(比較硏究))

  • Lee Hwa-Sin;Whang Wei-Wan
    • Journal of Oriental Neuropsychiatry
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    • v.6 no.1
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    • pp.19-39
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    • 1995
  • In order to compare the anti-stress effect of Guibitang with that of ascorbic acid, after these medicines were administered to guinea pigs induced by heating and swimming stress, the changes of the weight of body and organ, and content of plasma catecholamines, serum total cholesterol, free cholesterol, triglyceride, protein, glucose and cortisol were measured. The results were as follows : 1. The weight of the body was increased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 2. The weight of spleen decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, the weight of spleen decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. The weight of adrenal decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress alone. 3. Plasma norepinephrine content decreased with statistical significance not only in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group administered ascorbic acid on heating stress. In case of swimming stress, norepinephrine decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 4. Plasma dopamine content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 5. Serum total cholesterol content decreased with statistical significance in the groups administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, it decreased with statistiscal significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 6. Serum triglyceride content decreased with statistical significance not only in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group adminstered ascorbic acid on heating stress. In case of swimming stress, triglyceride decrease with statistical significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 7. Serum glucose content increased with statistical significance in the groups administered Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress, particulaly in case of swimming stress, in the group administered ascorbic acid with Guibitang, it increased with statistical significance as compared with in the group administered ascorbic acid. 8. Serum cortisol content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress.

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Deodorization of Purified Fish Oil from Squids by Organic Acids (유기산물 이용한 오징어 어유의 어취 개선)

  • Jang, Min-Kyung;Lee, Ok-Hee;Kim, Nam-Young;Yu, Ki-Hwan;Jang, Hye-Ji;Lee, Seung-Woo;Park, Mi-Ra;Park, Joung--Hyun;Kim, Mi-Hyang;Ha, Jong-Myung;Bae, Song-Ja;Lee, Sang-Hyeon
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1284-1288
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    • 2009
  • To produce high quality fish oil products, additional deodorization experiments on purified fish oil from squid using columns filled with citric acid or gluconic acid were performed. A deodorization effect on the fish oil was observed on both the citric acid and gluconic acid columns. These effects were more efficient on the columns packed with 3 g of organic acid than those with 1 g or 2 g of organic acid. In addition, a better effect was observed in the column packed with gluconic acid than that with citric acid. Peroxide value (POV) and acid value (AV) of the sample treated with citric acid was the as same as the non-treated sample. However, POV and AV of the sample treated with gluconic acid were about 10% higher than the non-treated sample. Contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of the samples treated with citric acid or gluconic acid columns were about 0.5% higher than the non-treated sample. In conclusion, deodorization of squid fish oil by organic acid could be an efficient method to produce high quality fish oil products.