• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1359-1366
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• 2004

Ultra high temperature treated (UHT) skim milk and colloidal calcium phosphate-free skim milk were treated with microbial transglutaminase (TGase), ultracentrifuged at various rates, lyophilized, and observed for morphological properties with a scanning electron microscope (SEM). UHT skim milk showed small holes of associated micelles at lower centrifugal rates, and became thick and irregular, and fine particles were associated regularly at higher centrifugal rates. When UHT skim milk with TGase was incubated for 1 hour, casein micelles aggregated and broadened as centrifugation rate increased. When UHT skim milk with TGase was incubated for 8 hours, casein micelles were associated irregularly to large aggregates and widened. Colloidal calcium phosphate-free skim milk with TGase incubated for 1 hour and separated by two-step centrifugation showed aggregated lump, while the milk incubated for 8 hours with TGase was associated with broadened, compact, and regular layers as the centrifugation rate increased. Such phenomena were caused by heat treatment, protein crosslinking reaction catalyzed by TGase and conformational changes of casein molecules, and could be dependent on reaction time, temperature and ultracentrifugation rate.

• Culinary science and hospitality research
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• v.18 no.3
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• pp.149-162
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• 2012

This study is intended to investigate the effects of customers' emotional response upon behavioral intention with taking customers who visited Korean restaurants into account. Luxury Korean restaurants where we apply to this study are selected by the food service industry association of Busan-metro city among the model restaurants. For this aim, designing a research model and drawing a hypothesis were carried out with a basis of advanced research. In data processing, SPSS win package 15.0 statistical program was used to verify the hypothesis through frequency analysis, reliability analysis, factor analysis, and regression analysis. The result of the analysis on the effects of physical environment factor upon domination among emotional response could be summed up as follows. Employee and geniality factors turned out to exercise a significant impact on domination, convenience and cleanliness turned out not to. The result of the analysis on the effects of physical environment factor upon arousal among emotional responses could be summed up as follows. Cleanliness and geniality factors turned out to exercise a significant impact on evocation, convenience while employee factor turned out not to. As a result of the analysis on the effects of emotional response upon behavioral intention, domination and evocation factors among emotional responses had a statistically significant impact upon behavioral intention. From the findings of the study, it became evident that dining-out customers might regard luxury Korean restaurants as a space for experiencing various emotions by physical environment rather than for dining and meeting for friendship. To induce emotional response is therefore expected to help a company to promote the practical improvement in achievement over various aspects such as behavioral intention.

• Journal of the Korean Chemical Society
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• v.18 no.4
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• pp.223-238
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• 1974

CNDO/2 MO theoretical studies and kinetic studies of halide exchange reactions for alkylchloroformates have been carried out in order to investigate structure-reactivity relationship of alkylchloroformates. From the result of energetics, it was concluded that the most stable configuration of alkylchloroformate is that in which alkyl group and chlorine are trans to each other, and that the hindered rotation about the bond between the carbonyl carbon and alkoxy-oxygen bond is attributed to the ${\pi}-$electron delocalization. It has been found that the large charge separation is due to -M effect of carbonyl and alkoxy oxygens and-I effect of chlorine. The order of rates in solvents studied was $(CH_3)_2 > CO > CH_3CN{\gg}MeOH.$$I^->Br^->Cl^-$ in protic solvent, and of Cl^->Br^- >I^-$ in dipolar aprotic solvents. Alkyl group contribution has the decreasing order of $CH_3-> C_2H-{\gg}i-C_3H_7-.$ The solvent effect has been interpreted on the basis of initial and final state contribution. A transition state model has been suggested, and it has been proposed that the most favorable mechanism is the addition-elimination. From the results of activation parameters and electronic properties, an energy profile has been proposed. Structural factors determining reactivities of alkylchloroformates have been shown to be charge, energy level of ${\alpha}^*LUMO$ to C-Cl bond and ${\alpha}^{\ast} $antibonding strength with respect to C-Cl bond in this MO. Charge and polarizability of nucleophile, and the interaction of these effects with solvent structures are also found to be important.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.455-462
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• 1995

The new six herbicidal N-[(pyrimidin-2-yl)aminocarbonyl]-2-substituted-6-(1-hydroxy-2-fluoroethyl)benzenesulfonamide derivatives(S) were synthesized and rate constants for the hydrolysis of thier in the range of pH $1.0{\sim}10.0$ have been studied in 15%(v/v) aqueous acetonitrile solution at $45^{\circ}C$. From the basis of the results, pH-effect, solvent effect, ortho-substituent effect, thermodynamic parameters(${\Delta}H^{\neq}$ & ${\Delta}S^{\neq}$), pKa constant(4.80), rate equation, analysis of hydrolysis products(2-(1-hydroxy-2-fluoroethyl)benzenesulfonamide & 4,6-dimethoxyaminopyrimidine), it may be concluded that the general acid catalyzed hydrolysis through $A-S_E2$ mechanism and specific acid catalyzed hydrolysis through A-2 type(or $A_{AC}2$) mechanism proceeds via conjugate acid($SH^+$) and tetrahedral intermediate(I) below pH 8.0, whereas, above pH 9.0, the general base catalyzed hydrolysis by water molecules(B) through $(E_1)_{anion}$ mechanism proceeds via conjugate base(CB). In the range between $pH\;7.0{\sim}pH\;9.0$, these two reactions occur competitively.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.75-79
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• 1997

적절한 약물요법의 목적은 효과적인 약리반응을 얻는 것이며 이를 위한 적정용법은 결국 \circled1 원하는 약물농도를 얻기 위한 용량과 투약법을 결정하는 약동학적 특성과 \circled2 용량-반응의 관계로부터 구하여진다. 그러나 약동학적 과정에 의해 결정되는 용량-농도 관계의 개체내 변이, 개체간 변이 등과 같은 약동학적 변이를 제거한 약물의 농도-반응의 관계가 용량-반응관계 보다는 더 직접적이며 이러한 농도-반응의 관계인 약력학적인 특성이 유효한 약물효과를 얻는데 필요한 약물투여 방법을 결정하게 된다. 역사적으로 볼 때 Brodie(1967)의 항말라리아 제재의 농도와 효과관계에 관한 연구와 같은 초기의 연구이래 많은 연구가 주로 약동학적 특성 즉 용량-농도의 관계에 관해 이루어져 최근 20여년 사이에 큰 발전을 보였으며 이는 약물농도의 분석에 필요한 분석화학적 기기와 방법의 발전에 힘입은 바가 크다 하겠다. 이에 비해 생체에서의 약력학적 연구의 발전은 최근까지도 미미하였으며 그 이유는 많은 약물에서 약리효과와 치료효과의 관계가 불명확하다는 것과 약리효과의 재현성 있는 측정에 어려움이 있다는 것 그리고 측정된 약리효과와 약물농도와의 연관성을 분석하는 방법론의 난점 때문이었다. 최근에는 제산제의 위내 pH의 변화나 중추신경계 작용 약물의 뇌파에 대한 변화와 같이 비침습적으로 재현성 있는 약물효과 측정법이 개발되고 있어 앞으로 많은 연구가 기대된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.193-196
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• 2006

This paper presents the results of catalytic endo- to exo- isomerization of saturated poly cyclic compound. Several zeolites were tested and influences of, Si/Al ratio and Structures of the zeolites on the reaction were investigated. The results showed that Y zeolites were more active than other zeolites, because of its large pore size and relative strong acidity. In all Y zeolites with different Si/Al, Y-5.4 is best. In all the zeolites tested, Y calcined at $450^{\circ}C$ was favorable. Still now the aluminium chloride catalyst is more active than zeolites. However, considering of environmental problems, corrosion, and treatment can make the zeolite catalyst substitute the aluminium chloride catalyst.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.119-128
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• 2005

모든 알레르기 반응의 중심축이 되는 비만세포는 주로 피부, 위장관 및 호흡기관의 점막에 분포하고 있다. 활성화된 비만세포는 즉각형 알레르기 반응을 일으키는 여러 인자들을 방출시키게 된다. 方藥合編(방약합편)에 따르면 蔘蘇飮(삼소음)은 알레르기 鼻炎(비염), 發熱(발열), 風寒(풍한), 頭痛(두통), 기침에 效能(효능)이 있는 處方(처방)이다. 본 硏究(연구)는 蔘蘇飮(삼소음)의 肥滿細胞(비만세포) 의존성 아나필락시 반응(anaphylactic reaction)에 대한 藥理(약리) 效果(효과)를 조사하기 위한 것이다. 蔘蘇飮(삼소음)은 compound 48/80으로 유발되는 전신성 아나필락시 쇼크(systemic anaphylactic shock)와 耳介(이개) 浮腫(부종) 反應(반응)(ear swelling response)을 농도 의존적으로 억제하였다. 蔘蘇飮(삼소음)을 0.1, 1 mg/ml로 전처리 하였을 때, 흰쥐 복강 肥滿細胞(비만세포)(rat peritoneal mast cells, RPMCs)에서 compound 40/80에 의해 유발되는 히스타민 분비는 감소하는 것으로 나타났다. 또한 蔘蘇飮(삼소음)은 anti-dinitrophenyl IgE에 의해 활성화 된 수동 피부 아나필락시(passive cutaneous anaphylaxis, PCA)를 농도 의존적으로 抑制(억제)하였다. 결론적으로 蔘蘇飮(삼소음)은 肥滿細胞(비만세포) 의존성 즉각형 알레르기 反應(반응)을 抑制(억제)하여, 항 아나필락시 활성(anti-anaphylactic activity)을 가지는 것으로 보여 진다.

• KSBB Journal
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• v.9 no.5
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• pp.525-531
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• 1994

Tyrosinase has two types of enzymatic activities, cresolase catalyzing the hydroxylation of monophenol and catecholase catalyzing the oxidation of o-phenol. Gradual inactivation of the enzyme during the reaction is a barrier to be overcome for the commercial application of the enzyme. Tyrosinase was stabilized by modifying the lysine residue of the enzyme using glutaraldehyde. In addition to that, tyrosinase was also stabilized by adapting the continuous reactor system. In packed bed reactor quinone could be easily removed, so the stability of tyrosinase increased. Borate buffer retarded the reaction rate of catechol to quinone and consequently decreased the tyroslnase inactivation. Tyrosinase immobilizer on controlled pore glass showed significantly enhanced stability in a packed-bed reactor.

• Journal of the Korean Chemical Society
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• v.20 no.6
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• pp.453-459
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• 1976

Rate constants for the reaction of methyl chloroformate with substituted anilines, and for the halogen exchanges in phenyl chloroformate have been determined in acetone. Although the rate data can be interpreted equally well with the addition-elimination mechanism($S_AN$) involving an intermediate, results of MO and isotope effect studies strongly favor the synchronous ($S_N2$) mechanism for the reactions studied. It was concluded that for the fast reacting nucleophiles the transition state is of "late" type while for the slow reacting nucleophiles it is of "early" type.

• Journal of the Korean Chemical Society
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• v.19 no.1
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• pp.11-15
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• 1975

Kinetic study of halogen exchange for N,N-dimethylcarbamoyl chloride and N,N-diethylcarbamoyl chloride in acetone by using radioisotopic halide ions has been carried out at two temperatures as a part of studying the reactivity of carbonyl carbon atom. The order of nucleophilicity showed a similar tendency as that for alkyl chloroformate, but reaction rate is much slower than that for solvolysis and alkyl chloroformate. The activation parameters,${\Delta}H^*$and${\Delta}S^*$ were found to decrease in sequence $Cl^{\rightarrow}Br^{\rightarrow}I^-$ for N,N-dialkylcarbamoyl chlorides. The results are interpreted in terms of solvation effect, degree of bond-breaking and bond-formation and electronic requirements.