• 한국식품영양과학회지
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• 제27권3호
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• pp.553-562
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• 1998

Food allergy is defined as an immunologically-mediated adverse reaction to food.The food allergy as a clinical entity has been recognized for many years, although there is yet no general consensus as to the incidence of this syndrome. One difficulty in studying food allergies has been the lock of a reasonable animal model in which reactions could be induced by orally administrating foods. It has been generally accepted that the initial target for an immediate reaction to food is the mast cells, within the gastronitestinal mucosa, and such cells are sensitize in vivo by food-specific immunoglobulin(Ig) E. Degranulation of these cells facilitates the entry of an antigenic epitope into the lymphatic system and blood stream, thereby causing further degranulation of the mast cells and basophils throughout the boy. Accordingly, the author attempted to develop an animal model that is indicative of evaluating IgE-mediated immediate hypersensitivity. It is also necessary to evaluate the effects of nutritional envioronments on dietary protein-dependent allergy and the regulatory mechanisms of dietary fats on IgE-mediated immune response. In this review, animal models to evaluate a food ingredient, effects of dietary fats and curcuminoids, milk whey protein hydrolysates on allergic reaction, and effect of dietary fat in splenic immune cells are presented.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1100-1103
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• 2003

One of the good ways to raise the rate of the electrochemical reaction is to broaden the effective surface area of the electrode by developing cylindrical nano-pores on the surfaces. The numerous pores of several nanometer in diameter can be used to enhance a specific faradaic reaction so that the nano-porous structure attract keen attention in terms of implication of new bio/chemical sensors, in which no chemical modification is involved. Amperometric glucose sensor is a representative example that needs the selective enhancement of glucose oxidation over the current due to physiological interferents such as ascorbic acid. The present paper reports how the ascorbic acid and glucose diffuse around the nano-porous surface by simulation study, for which 2D-FDM (Finite Difference Method) was adopted. The results of the simulation not only consist with those from electrochemical experiments but also reveal valuable potential for more advanced application of the nano-porous electrode.

• Journal of Advanced Marine Engineering and Technology
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• 제30권8호
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• pp.853-862
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• 2006

The present study is numerically investigated the flame structure of non-premixed counterflow jet flames using the laminar flamelet model Detailed flame structures with the fuel composition of 40% CO, 30% $H_2$. 30% $N_2$ and an oxidizer composition of 79% $N_2$ and 21% $O_2$ in a non-premixed counterflow flame are studied numerically. This study is aimed to investigate the effects of axial velocity gradient and combustion atmosphere pressure on flame structure. The results show that the role of axial velocity gradient on combustion processes is globally opposite to that of combustion atmosphere pressure. That is, chemical nonequilibrium effects become dominant with increasing axial velocity gradient, but are suppressed with increasing ambient pressure. Also, the flame strength is globally weakened by the increase of axial velocity gradient but is augmented by the increase of ambient pressure. However, flame extinction is described better on the basis of only chemical reaction and in this study axial velocity gradient and ambient pressure play a similar role conceptually such that the increase of axial velocity gradient and ambient pressure cause flame not to be extinguished and extend the extinction limit, respectively. Consequently it is suggested that a combustion process like flame extinction is mainly influenced by the competition between the radical formation reaction and the third-body recombination reaction.

• Journal of Microbiology and Biotechnology
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• 제12권5호
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• pp.801-806
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• 2002

A multiplex competitive polymerase chain reaction (PCR) method was developed for the rapid identification and quantification of Leuconostoc mesnteroides and Lactobacillus plantarum populations which are the key microorganisms in kimchi fermentation. The strain-specific primers were designed to selectively amplify the target genes encoding 165 rRNA of L. plantarum and dextransucrase of L. mesenteroides. There was a linear relationship between the band intensity of PCR products and the number of colony forming units of each model organism. The PCR quantification method was compared with a traditional plate-counting method f3r the enumeration of the two lactic acid bacteria in a mixed suspension culture and also applied to a real food system, namely, watery kimchi. The population dynamics of the two model organisms in the mixed culture were reliably predictable by the competitive PCR analysis.

• 대한기계학회논문집B
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• 제31권3호
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• pp.225-233
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• 2007

The growth of GaN on the patterned substances has proven favorable to achieve thick, crack-free GaN layers. In this paper, numerical modeling of transport and reaction of species is performed to estimate the growth rate of GaN from tile reaction of TMG(trimethly-gallium) and ammonia. GaN growth rate was estimated through the model analysis including the effect of species velocity, thermal convection and chemical reaction, and thermal condition for the uniform deposition was to be presented. The effect of shape and construction of microscopic pattern was also investigated using a simulator to perform surface analysis, and a review was done on the quantitative thickness and shape in making GaN layer on the pattern. Quantitative analysis was especially performed about the shape of reactor geometry, periodicity of pattern and flow conditions which decisively affect the quality of crystal growth. It was found that the conformal deposition could be obtained with the inclination of trench ${\Theta}>125^{\circ}$. The aspect ratio was sensitive to the void formation inside trench and the void located deep in trench with increased aspect ratio.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권2호
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• pp.70-77
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• 2003

유해유기물질의 미생물 분해시 일어나는 총괄반응을 이론적으로 예측하는 방법을 기술하였다. 열역학적 이론을 바탕으로 하는 반쪽반응 방법을 사용하,였고, 최근에 도입된 이론들인 중간체 생성 반응, oxygenation반응, 그룹이론에 의한 표준 자유생성에너지 예측기법 등을 적용하였다. 대표적인 유해유기물질인 phenanthrene과 함께 glucose, hexadecane의 미생물 분해 반응식을 실제로 계산하였다. 예측된 총괄반응식을 이용하여 미생물 수율, 산소 요구량, 질소 요구량, 무기화율 등의 정보를 얻을 수 있었으며, 이는 오염된 지하수/토양의 생물복원 공법 설계 및 자연정화평가 등에 유용하게 적용될 수 있을 것으로 기대한다.

• 공업화학
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• 제17권1호
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• pp.33-36
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• 2006

광경화 접착제로 많이 사용되는 우레탄-아크릴레이트 올리고머의 광경화 거동을 자체촉매화 반응모델식을 통해 중합온도 및 올리고머의 관능성에 따른 영향을 확인하여 보았다. 중합온도가 증가함에 따라 최대중합속도는 감소하여 중합온도가 경화 거동에 대한 영향인자임을 확인할 수 있었으며, 반응속도상수 k는 온도증가에 따라 거의 일정한 값을 보이나 반응차수 m과 n은 증가하는 경향을 보였는데 이는 가교구조에 의한 반응성 기의 확산제한 및 유동성의 제한으로 인한 것으로 판단되어진다. 온도증가에 따른 중합속도의 감소는 주로 반응차수 n의 증가에 의해 진행되었다.

• 한국지반공학회지:지반
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• 제8권2호
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• pp.59-70
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• 1992

지질구조의 일례를 모형화하여 3종류 시료에 대해 간극수압계를 사용하여, 가압수두와 간극비 변화에 따른 간극수압 변화측정을 60회의 실험을 통하여 실시하였다. 본 연구는 불포화 붕적토층에서 간극비와 가압수두 변화에 따른 간극수압의 변화를 기록하여 최종간극수압 VWT와 공기간극수압 Ua를 구하여 이들의 변화를 최종반응률과 공기반응률로 나타냈으며, 시료별로 투수계수와 간극비의 관계를 수식화 하였다. 실험결과 시료에 따라 간극수압 변화 형태가 계단형과 파형으로 나타났으며, 최종간극수압까지의 시간 지체는 모래, 사질실트, 점토질 모래 순이었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.1996-2000
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• 2008

In autothermal reforming reaction, oxygen to carbon ratio (OCR) and steam to carbon ratio (SCR) are significant factors, which control temperature and carbon deposition into the reactor. The OCR is more sensitive than the SCR to affect the temperature distribution and reforming efficiency. In conventional operation, hydrocarbon fuel, steam, and oxygen was homogeneously mixed and injected into the reactor in order to get hydrogen-rich gas. The temperature was abruptly raised due to fast oxidation reaction in the former part of the reactor. Deactivation of packed catalysts can be accelerated there. In the present study, therefore, the effect of the oxygen distribution is introduced and investigated to suppress the carbon deposition and to maintain the reactor in the mild operating temperature (e.g., $700{\sim}800^{\circ}C$). In order to investigate the effect numerically, the following models are adopted; heterogeneous reaction model and two-medium model for heat balance.

• Elastomers and Composites
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• 제37권2호
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• pp.124-133
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• 2002

온화한 조건($80{\sim}110^{\circ}C$, 대기압)하에서 비누화반응에 의해 폐 PBT의 입자를 해중합하여다. PBT의 해중합은 KOH 보다 NaOH가 보다 효과적이었으며, 반응온도가 증가하고 입자의 크기가 작을수록 해중합은 증가하였다. 해중합속도는 표면반응이 율속단계로서 PBT 입자표면에 생성물이 형성되지 않은 미반응핵 모델에 의해 표현할수 있었다. 겉보기활성화에너지는 98.1KJ/mol 이었으며, 85.1, $105{\mu}m$인 PBT 입자를 6시간 동안 해중합하였을때 TPA의 회수율은 약 95%정도였다.