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        검색결과 2,503

        2361.
        1991.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Four novel amphoteric surfactants of N-(2-alkylamidoethyl)-N, N-dimethyl ammonioacetates were synthesized. The each reaction between four saturated fatty acids containing 10, 12, 14 and 16 carbon atoms and N, N-dimethylethylene diamine permitted to give the intermediate products, N-(2-alkylamidoethyl)-N, N-dimethylamines. Quaterinzation of these intermediates was permitted to form N-(2-alkylamidoethyl)-N, N-dimethyl, ammonioacetates, whose sturctures were identified by CC, TLC, elemental analysis, IR pectrophotometry and 1HNMR spectrometry. The products yielded from 48% to 58%. The isoelectric points were shown in the range of 4.30~6.64. It showed a tendency to learn to the acidic site and its range was broadened as increase of the hydrophobic group length. Surface tensions of the aqueous solution in the 10-6~10-1mol/l of amidobetaines were measured. and the critical micell concentration(cmc) were shown in the range of 8.37×10-6~8.96×10-2mol/l, and γcmc were reduced to 32.3~38.2 dyne/cm. A linear relationship between log cmc and the number of carbon in the hydrophobic alkyl chain was presented by the formula of log cmc=2.38-0.5n, and the contribution-rate of n on the standard free energy change in micellization ɘ(δG0m)/ɘn, was calulated as -0.5RT.
        4,000원
        2362.
        1991.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In relation to the preparation of Langmuir-Blodgett thin film, four kinds of N-alkylpyridiniurn bromide were synthesized. The values of surface tensions of these materials, measured with a Traube stalagmometer, gave the relationship between the critical micells hydrophobic radical and between CMC and temperature. Values of thermodynamic properties(δH0m, δS0m, δG0m,) for the formatoin of micelle were also obtained. Experiments gave the following results; at the temperature range between 40 and 60℃, CMC of Hexadecyl-, Octadecyl-, Eicosyl-, and Docosyl-Pyridinium Bromide were 7.64×10-4~9.13×10-4, 3.85×10-4~4.60×10-4, 2.00×10-4~2.39×10-4, and 1.07×10-4~1.28×10-4 mol/l, respectively. Surface tension, γCMC, of those were 33.49~36.00, 34.78~37.61, 35.49~37.61 and 38.76~55.80 dyne/cm, respectively, The relationship between CMC and the mumber of carbon atoms in the hydrophobic radical, N was expressed as follows : Log(CMC)=A-BN where A and B are constants. At the temperature range between 40 and 60℃, the change of Gibbs evergy (δGm) for one methylene group (-CH2-) were -0.65RT, respectively, The minus values of enthalpy change (δHm) suggest that the formation of micelle is exothermic. Additionally, the overall increase in the entropy change (δSm) with respect to the temperature increase suggests that the formation of micelle is attained by a exothermic enthalpy directed process.
        4,000원
        2363.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The thermodynamics of micellization of a new series of ionic surface-active agents, dimethyl alkyl-2-deoxy-2-epi-inosityi-ammonium chlorides, has been examined, A minimum in the critical micelle concentration versus temperature has been observed at 25℃ It has been found that the standard entropy of micellization is always positive showing that miceliization is governed by the gain in entropy associated with the removal of the monomer from an aqueous environment to the micelle over a 15℃ to 45℃ temperature while governed by enthalpy directed process below 25C˚.
        4,000원
        2364.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The extracts of Quercisemen(Quereus acutissima Carruthers seed) powder was obtained by the extraction with distilled water, water : acetonet(1:1, v/v), ethanol and ethyl ether, respectively. As a result this experiment, the antioxidative activity of each solvent extracts on linoleic acid were examined as follows: 1. Each fraction extracted by the acetone : water(1:1, v/v), water and ethanol respectively showed high antioxidative activity. 2. A fraction of the tannin extracted from the solvent, acetone, water(1:1, v/v) showed even more antioxidative activity than that of the α-tocopherol or BHT. 3. Acceleration of peroxide reaction by Fe++ and Cu++ on the linoleic acid was strongly inhibited by adding the tannin, 4. Organic acid, such as malic acid, citiric acid and tartaric acid with the tannin were showed the synergistic effect fo the antioxidation reaction.
        4,000원
        2365.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Frog legs were stored before and after 30, 60, 90, 120 days at -30℃ and -70℃. The amounts of triglycerides, glycolipide and phospholipids by TLC and composition of fatty acids by GC were shown in this experiment, there fore, I have got these following results. 1. The amount of PL in frog legs consisted of 80% of the total lipids before storage. As the days of storage was longer, the amount of TG was increased, while PL and GL were decreased. 2. TG and ES & HC were composed of 66% to 77% of the neutral lipids composition before storage. As the days of storage was longer, the amount of MG, DG. FFA and ES & HC were increased, while FS and TG were decreased. 3. PE and PC were composed of 78% to 81% of the phospholipids composition before storage. As the days of storage was longer, the amount of FA and PS were increased, while PC and PE were decreased. 4. The composition of fatty acids in neutral lipids of frozen frog legs at -30℃, 120 days was studied, Capric acid. Stearic acid, Behnic acid. Oleic acid and Linoleic acid were increased as compared with initial neutral lipids.
        4,000원
        2366.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The reactions of semicarbazide hydrochloride with aliphatic and alicyclic ketones were studied kinetically at 15, 25, 35 and 45℃ in 20% ethanol solution buffered at pH 2.9. The rate of cyclohexanone semicarbazone formation is 5.5 times as fast as that of cyclopentanone semicarbazone, while 3-pentanone semicarbazone is 4.7 times as slow as that of 2-pentanone, The activation energy of cyclohexanone, 2-pentanone, 2 hexanone, cyclopentanone, 4-methyl-2-pentanone and 3-pentanone semicarbazone formation are calculated 5.08, 7.52, 8.79, 9.59, 9.49, 11.59, respectively. It is concluded from the effect of ionic strength that the reaction is affected by not ion but neutral molecules being progressed hydrogen bond between oxygen atom of carbonyl group and hydrogen atom of acid-catalyst and concerted nucleophilic attack of free base on the carbonly compound. Dependence on pH of the rate of 2-pentanone semicarbozone formation is linear relationship below pH 4.60 and above pH 5.60. As a result of studing citric acid catalysis, second order constants increase linearly with citric acid concentration. As the catalyst concentration is varied from 0.025 to 0.10 mol/1 at pH 2.90, the rate constants increase 1.4 times, but slight increase is observed at pH 5.60. Conclusively, the rate-determining step is formation of tetrahedral interemediate below pH 4.65 and dehydration between pH 5.60 and pH 7.11. It is concluded that the formation reaction of cyclohexanone semicarbazone is faster than cyclopentanone semicarbazone due to the steric strain in the process of forming tetrahedral intermediate.
        4,000원
        2367.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Biosurfactant have a low toxicity, good biodegradable, various structure. It can be used for a broad range of purposes in a large variety of different applications. Sorbitol mono alkyl ester synthesized by the Porcine Pancreatic lipase catalyzes transesterification reaction between a sugar alcohol and plant oils. We are examined the surface tension, emusion stability and critical micelle concentration were evaluated. Consequently It has a good properties of biosurfactant.
        3,000원
        2368.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The seeds of wild and cultivated Camellia japonica were studied for their lipid contents and fatty acid composition. The seeds of wild and cultivated Camellia japonica contained 70.2% and 73.4% lipids, respectively. Fifteen fatty acids were identified in the lipids from the Camellia japonica seeds. In addition to confirming the 5 previously reported (16 : 0, 18 : 0, 18 : 1, 18 : 2 and 18 : 3), 10 more acids were characterized. The newly identified acids were 14 : 0, 16 : 1, 17 : 0, 20 : 0, 20 : 1, 20 : 2, 22 : 0, 22 : 1, 24 : 0 and 24 : 1. Both seeds lipids contained 18 : 1 in high levels (81. 6~82. 2%). Little difference in fatty acid composition was noted between the wild and cultivated Camellia japonica seed lipids. The fatty acid composition of commercial Camellia japonica oil was similar to those of the Camellia japonica seed lipids.
        3,000원
        2369.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The synthesis of urocanic acid which was started D-fructose, and its alkyl esters, urocanic ethyl ester and urocanic isobutyl ester, were prepared by esterificated. Urocanic ethyl ester and urocanic isobutyl ester were insoluble in water and soluble most organic solvents (ethanol, benzene, toluene, pyridine, THF, DMF) which adds to their practical applicability, and absorb ultraviolet light of greater wavelength than the free acid and there by are more effective for shielding sensitive materials, including the humanbody, from the chemically most effective portion of the solar ultraviolet spectrum.
        4,000원
        2370.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Dried seeds of Camellia japonica and Thea sinensis were investigated to determine the nature of their antioxidative activity. Activity was measured by the induction period in the coupled oxidation of a substrate lard and extracts or isolates to be tested. 70% methanol and dichloromethane extracts were found to be antioxidative abilities. Their unsaponifiables revealed weak antioxidative activity, although hexane extracts did not show antioxidative effect on lard. Column chromatography for dlchloromethane extracts gave 4 fractions(only 2 fractions were potent). HPLC was used in isolating potent antioxidative components from the column fractions and the precolumn-passed methanol extracts. They were separated into 7 and 8 components, respectively. The column fractions obtained from both seeds comprised trans-p-coumaric acid. trans-p-ferulic acid and an unknown component with minor components such as chlorogenic acid and catechin. On the other hand, the most prominent components in the methanol extracts were an unidentified component. trans-pcoumaric acid, trans-p-ferulic acid, catechin and chlorogenic acid. The unknown compound isolated from the column fractions and methanol extracts was identified as epicatechin by 1H-and 13C-NMR. The antioxidative activities of these components were epicatechin 〉 catechin 〉 chlorogenic acid 〉 trans-p-ferulic acid 〉 trans-p-coumaric acid.
        4,000원
        2371.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        동백종실유(冬栢種實油)에서 컬럼크로마토그래피로 지질(脂質) 성분(成分)을 상호(相互) 분리(分離)하였다. 여기서 얻은 트리글리세리드의 일부(一部)를 취하여 알칼리로 가수분해(加水分解)하거나 또는 pancreatic lipase로 가수분해(加水分解) 하여, 트리글리세리드의 구성(構成) 지방산(脂肪酸) 또는 1, 3- 위치(位置)와 2-위치(位置)에 급합(給合) 한 지방산(脂肪酸) 조성(組成)을 조사(調査)하였다. 나머지 트리글리세리드는 16% AgNO3 TLC로 이중결합선(二重結合敾)별로 나누었으며, 이렇게 나누어진 분획(分劃)을 다시 HPLC로 PN별로 재분획(再分劃) 하였다. 여기서 얻어진 획분(劃分)들 중 PN이 같은 것은 모두 모아서 알칼리 가수분해(加水分解)로 PN의 총지방산(總脂肪酸) 조성(組成)을, pancreatic lipase로 1,3 위치(位置)에 결합선(結合敾)한 지방산(脂肪酸)의 조성(組成)을 조사(調査) 하였다. 여기서 얻어진 결과(結果)로 부터 구성(構成) 트리그리셀리드 분자종(分子種)을 산출(算出)하였더니 다음과 같은 결과(算出)를 얻었다. 1) 종실유(種實油)는 투명(透明)한 액체(液體)로 그 함량(含量)이 73.5%였으며, 그 중 트리글리세리드가 94.8%, 극성(極性) 지질(極性)이 2.0%, 탄화(炭化) 수소(水素)가 1.8%였다. 2) AgNO3-TLC로 트리글리세리드를 분획(分劃)하였더니 5개의 획분(劃分)을 얻었으며, 대부분(大部分)의 트리글리세리드가 이중(二重) 결합선(結合敾) 3~5개인 band 2와 band 3에 80% 이상 존재(存在)하였다. 3) AgNO3-TLC에서 얻은 각 획분(劃分)은 모두가 HPLC상에서 PN 46, 48 및 50으로 나누어졌으며 전체(全體) 분획(分劃)에서 PN 48이 78.13%로 제일 많았으며, 다음으로 PN 50이 12.04%였으며, PN 46이 9.83%였다. 4) 전체(全體) 트리글리세리드 분자종(分子種) 중에서 0.1mol% 이상을 차지하고 있는 분자종(分子種)이 43종(種)이었으며, OOO와 POO가 각각 39.8mol%와 25.8mol%로 제일 많았으며, 그 다음으로 OPO가 5.5 mol%, OOL가 4.8 mol%, POS가 3.9mol%, SOO가 3.5mol%. POL이 3.0mol%였다. 또 동백종실유(冬栢種實油)에 존재(存在)하는 트리글리세리드의 분자종(分子種)의 조성(組成)은 1,3-random, 2-random 분포설(分布說)에 따라 구성(分布說)되어 있었다.
        4,000원
        2372.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The rate constants for the addition reaction of thiourea to nitrone derivatives were determind at various pH and reaction rate equation which could be applied over a wide pH were obtained. The substituent effects and general base catalysis for the addition of thiourea to nitrone derivatives were observed. On the basis of these findings, a plausible reaction mechanism for the nucleophilic addition of thiourea to nitrone was proposed.
        4,000원
        2373.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In the preparation of acrylic water repellent(EDLWC). quaternized 2-diethylarrunoethylmethacrylate-stearylmethacrylate copolymer (DSACC) and quaternized 1-Iaurovlbis(aminoethyl)-2-dodecylimidazoline(LDDIC) were selected as a basic resin and the improving agent such as softening effect and hydrostatic pressure of the water repellent. EDLWC was prepared by blending waxes and emulsifier for waxes with various ratio to DSACC and LDDIC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyester-cotton(P/C) blended fabrics treated with EDLWC only or addition of textile finishing resin, the physical properties were increased. Sodium acetate was the most effective catalyst in the water repellency among the various kinds of catalyst. and the reasonable concentration of the catalyst was 1. 4 wt%. EDLWC was confirmed as durable water repellent with the results of making little difference of water repellency as ±5 point after and before washing. The reaction mechanism between P/C blended fabrics and EDLWC in the presence of catalyst was proposed. And also, the longitudinal view of the P/C blended fabrics treated with water repellent was observed with scanning electron microscope.
        4,300원
        2374.
        1991.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The kinetic of hydrolysis for cinnamylidene aniline derivatives has been investigated by ultraviolet spectrophotometry in 20% (v/v) dioxane - H2O at 25℃. A rate equation which can be applied over wide pH range was obtained. The substituent effects on cinnamylidene aniline derivatives were studied and the hydrolysis was facilitated by electron attracting group. Final products of the hydrolysis were cinnamaldehyde and aniline. From the rate equation, substituent effect and final products, the hydrolysis of cinnamylidene aniline derivatives was initiated by the neutral molecule of H2O which does not dissociate at below pH 9.0~12.0, but proceeded by the hydrogen ion at above pH 5.0~9.0.
        4,000원
        2376.
        1990.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was attempted to observe the effect of Job's tear diet on change of body weight and tissue in rat. The changes of body weight were higher in Job's tear non-diet group(A) and seemed to lower in Job's tear diet group(c) as expected. The weight of each organ appeared to heavy more C group than A,Bgroup in Brain, Spleen. Lungs and Kidney. Liver was heavier in Job's tear to diet one day among six day group(B) and ovary was lighter in C group, The levels of each organ TBA-value were higher in Brain, Liver of A group and showed to higher Spleen, Lungs, Ovary of C group TBA-value of Kidney was revealed to lower more C group than A,B group.
        4,000원
        2377.
        1990.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The study was observed that anti oxidation effect of each and mutual relation on BULGOGI seasoning in Fore shank and Ribs. Each antioxidation effect were appeared to higher in suger, pear juice, soya souce, clean wine, sesamed oil, green onion, toeasted sesamed powder, black pepper, garlic im seasoned immidiately. Soya souce was revealed to higher effect anti oxidation in storaged beef among 30 minuit after seasoned. In storaged sample among 9 hour after seasoned was showed to higher effect in soya souce & galic. Mutual relation of two seasoning in BULGOGI seasoning were revealed to higher effect in mixture of green onion & galic.
        4,000원
        2378.
        1990.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Gas-liquid chromatography analyses have been carried out to investigate the fatty acid composition of 3 commercial Korean shortenings. Fourteen fatty acids ranged from caprylic to behenic acids were identified in all the samples. The major components in the samples were palmitic, stearic and oleic acids as the sum of 16:0, 18:0 and 18:1 ranged from 76-92% of total fatty acids. The ranges for saturated fatty acids, mono unsaturated fatty acids and polyunsaturated fatty acids in the samples were 49-50%, 41-42% and 4-6%, respectively.
        3,000원
        2379.
        1990.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        (2,3-Dibromopropyl) phenyl lauroyl phosphate[DPPL] was synthesized by adding lauric acid to (2,3-dibromopropyl)chloro phenyl phosphate [DPP]. which prepared from phenyl phosphoric acid dichloride with 2,3-dibromo propyl alcohol. Flame retardants of DPPF and DPPLF were prepared respectively. DPPF was a water soluble flame retardant, and DPPLF was o/w type emulsion flame retardant. After flame retardant treating two kinds of flame retardants to the various synthetic fabrics respectively. the flame retardancy and tear strength were measured. As the results of the measurement. DPPF had only name retardancy, but DPPLF had both of flame retardancy and softness.
        4,000원
        2380.
        1990.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To investigate the influence of saturated fats, α-linolenic acid, EPA and DHA on the lipid hydroperoxide concentration and fatty acid composition in liver microsomes and in plasma lipid of rabbits, the animals were fed on the perilla oil rich α-linolenic acid or sardine oil rich EPA and DHA diet for four weeks Were examined. The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the perilla oil diet was an accumulation of arachidonic acid(AA) 20:4 n-6, eicosapentaenoic acid(EPA) 20:5 n-3, and docosahexaenoic acid(DHA) 22:6 n-3, The fatty acid composition of plasma lipid and liver microsomes of rabbits fed on the sardine oil was an accumulation of α-linolenic acid(LNA) 18:3 n-3, and arachidonic acid(AA) 20:4. The p/s ratio of rabbits fed on the perilla oil diet changed from 7.4 to 2.27 for plasma lipid and 2.47 for liver microsomes. The concentration of lipid hydroperoxide was 3.48 nmol MDA/ml and 4.35 nmol MDA/ml for plasma lipid and liver microsomes, respectively, in perilla oil diet. The lipid hydroperoxide liver was 4.22 nmol MDA/ml and 67 nmol MDA/ml for plasma lipid and liver microsornes in sardine oil diet.
        4,000원