• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.149.1-149
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• 2003

방사선에 의한 식품 저장은 이미 그 건전성과 경제적 타당성이 인정되어 세계 여러나라에서 실용화되고 있다. 고사리(Pteridium aquilinum)는 참고사리과에 속하는 다년생 양치식물로서 봄철에 어린잎과 줄기를 삶아 물에 담구었다가 건조시켜 저장하였다가 이용하고 있다. 현재 유통되고 있는 건고사리는 수확, 건조 및 저장 중에 비위생적인 관리 등에 의해 미생물의 증식 및 해충의 발생 등으로 품질이 크게 저하되어 저장상 많은 어려움을 안고 있다. 선행연구에서 방사선 조사된 건고사리는 불림시 연화현상이 나타났으므로, 본 실험에서는 Co-60감마선을 건고사리에 조사하여 습열조리 조건에 따른 연화 특성을 분석하였다. 즉, 건고사리에 조사선량을 0, 3, 5, 7kGy로 달리 하여 조사하였고 조리온도, 조리 시간에 따른 연화정도 및 연화에 따른 활성화 에너지를 분석하였다. 결과 조사선량이 높을 수록 경도는 대조구에 비해 유의적으로 감소하였는데 조리온도, 시간 및 조사선량이 증가할수록 감소하였다. 활성화에너지는 조사선량이 증가함에 따라 감소하여 건고사리의 가열 조리시 에너지가 감소 됨 이 확인되었다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.253-258
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• 1996

본 연구는 Zr-2.5wt%Nb합금의 고온변형특성중 특이한 유동응력의 변화거동인 어닐경화와 유동연화의 기구에 대해 고찰하였다. 연구결과에서 이러한 고온변형특성은 온도와 다단변형도중의 어닐링 시간에 영향을 받는 것으로 나타났으나 분위기 영향은 없는 것으로 나타났다. 즉, 변형 온도와 동일온도인 85$0^{\circ}C$에서 단시간인 5분동안 어닐링을 했을때 경화현상이 일어났다. 미세조직을 관찰한 결과 다단열간압연된 후의 미세조직과 집합조직은 다단열간압연된 미세조직과 집합조직과 직접적인 상관관계를 가진 것으로 나타났다. 어닐경화현상은 다단고온변형이 궁극적으로 변형시효와 유사한 효과 즉, 중간어닐링 동안에 Zr-2.5wt%Nb내의 불순물 원자와 열간압연시에 형성된 전위구조와의 강력한 인력형 상호작용하여 substructure가 안정화되기 때문이며 유동연화는 재결정으로 인한 유동응력의 감소인 것으로 사료된다.

• Journal of the Microelectronics and Packaging Society
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• v.1 no.1
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• pp.51-60
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• 1994

RuO2 계 후막저항체에 사용된 유리의 입도 및 연화점이 후막저항체의 전기적 특성 에 미치는 영향을 시험하기 위하여 연화점이 서로 다른 두 종류의 유리를 제조하고 이들을 미분쇄하여 각각 세 조류의 평균입도로 분급하였다. 이 유리분말들을 이용하여 여섯 종류의 후막저항체를 제조하고 그 저항체들의 전기적 특성을 평가하고 고찰하였다. 연화점이 높은 유리로 만든 후막저항체들보다 높은 쉬트 저항을 나타냈다. 또한 후막저항체들의 쉬트 저항 및 저항온도계수는 저항체들의 미세조직과 밀접한 관계가 있음을 확인하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.195-195
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• 2003

PDP, FED 등의 디스플레이와 각종 IC 칩부품에 적용 가능한 저융점 유리 프릿 중에서 환경규제가 이루어지고 있는 납성분이 포함되어 있지 않은, Bi계 유리 프릿의 열적 거동 연구를 행하였다. 열처리 온도에 따른 열거동에 따라 프릿의 소성온도 및 미세구조가 결정되므로, 열처리 온도에 따른 유리 프릿의 젖음각을 측정하였고, DTA와 TMA를 통해 유리전이온도, 연화점, 열팽창계수 변화 경향성을 관찰하였다. 본 연구에서 제조된 유리는 조성에 따라 전이온도가 390-50$0^{\circ}C$, 연화점이 400-55$0^{\circ}C$, 열팽창계수가 65-120$\times$10-7/$^{\circ}C$ 범위를 나타내었으며, 고온현미경 측정 결과 Pb-계 유리와 비교시 유사한 열거동을 나타내었다.

• 어항어장
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• s.94
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• pp.53-56
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• 2011

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.243-247
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• 2019

Calendula (Calendula officinalis L.) petals are edible flowers which have been used as a decorative ingredient in dishes or as a medicinal food. In this study, the anti-skin aging potential of calendula petals was investigated. Additionally, the texture was softened by non-enzymatic methods to broaden their application as a food or cosmetic agent. Treatment of calendula prevented ultraviolet-induced matrix metalloproteinase-1 expression in skin cells. We investigated whether heating-based processing could soften calendula petals. The results from the punctual test demonstrated significant changes in the hardness of calendula petals depending on the pH, heating temperature, and time. Although there were minor differences among various processing conditions, the largest alteration in hardness was observed when the petals were softened by incubation at $80^{\circ}C$ and pH 2.3 for 120 min. Collectively, these results show that the application of proper processing conditions can soften calendula petals without using enzymes.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.515-519
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• 1987

The kinetics of thermal softening of chinese cabbage was investigated by puncture tests with an Instron. It was concluded that low temperature-long time blanching and pasteurization process provided an opportunity of improving the texture of pasteurized Kimchi. The rate of softening showed apparent first order kinetics, and the apparent Arrhenius activation energies ranged from 2.8-42.4 kcal/mol. The temperature dependency of the softening rate during pasteurization was more profound by blanching at blanching at higher temperature.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.95-99
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• 1988

The changes of texture, composition of cell wall polysaccharides, polygalacturonase (PG) activity and soaking effect during preserving of persimmon at various tempoeratures were estimated for the purpose of investigating the softening characteristics of persimmon fruit. The softening of persimmon was most promoted at $25^{\circ}C$, where in the higher temperature, at $45^{\circ}C$ it was inhibited. During softening adhesiveness increased, cohesiveness and gumminess decreased. This phenomenon was obvious at $25^{\circ}C$. By soaking in water at $50^{\circ}C,\;70^{\circ}C$ for 30 minutes PG activity and softening was inhibited. Ionically associated pectin (IAP) and covalently bounded pectin (CBP) fractionated from crude cell wall of fresh persimmon were respectively degraded about 60% by PG curde enzyme of softened persimmon. And the degraded ratio of polysaccharides composed of pentose and hexose was very similar to that of polyuronide.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.402-406
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• 2013

In this study, a pitch for melt-electrospinning was prepared from naphtha cracking bottom (NCB) oil by the modification with heat treatment. The softening point and property of the modified pitch was influenced by modification conditions such as nitrogen flow rate, heat treatment temperature, and reaction time. Among these, the heat treatment temperature had a very strong influence on the distribution of molecular weight and softening point of the pitch. The C/H mole ratio and average molecular weight increased with increasing the heat treatment temperature due the decomposition and cyclization reaction of surface-functional groups. In addition, the values of benzene insoluble and quinoline insoluble also tends to decrease, and the width of molecular weight distribution seems to get more narrow. The carbon fiber with a diameter of $4.8{\mu}m$ was prepared from a modified pitch at the softening point of $155^{\circ}C$ by melt-electrospinning. It is believed that the melt-electro spinning method is much more convenient to get the thinner fiber than the conventional melt spinning method.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.619-625
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• 1998

The effect of softening point and glass amount of glass frit on the sintering behavior of low temperature cofirable glass/ceramic composites was studied and according to these results, glass/ceramic composites with high sintered density was fabricated. The density of composites was increased as the glass amount was increased. In case of using the glass with low softening point, the deformation of specimen was occurred though the ratio of the glass amount in the specimen was low. But, in case of using the glass with high softening point, the sintered density of composites was increased in accordance with glass amount. With the specimen of high softening point, the deformation was not happened. Therefore, it was found that the densification was progressed continuously in high glass amount. From the study on the effect of softening point of glass on sintering behavior, the suitable softening point and glass amount for fabrication of glass/ceramic composites can be anticipated. When glass frit with softening point of $790^{\circ}C$ was chosen according to this result, low temperature cofirable glass/ceramic composites with high density (97%) at $900^{\circ}C$ was fabricated.