• 한국식품과학회지
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• 제20권3호
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• pp.331-337
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• 1988

국내에서 생산되는 다수확계 및 일반계 쌀 각 5품종을 Differential Scanning Calorimetry(DSC)로 열분석 하여 호화, amylose-lipid complex의 melting 및 노화 등의 상전이 현상들을 연구하였다. 다수확계와 일반계품종간에는 호화개시 온도에 있어서는 특정한 차이가 없었으나 호화의 온도범위는 다수확계가 약간 넓은 경향이었는데 다수확계가 더 큰 값을 보였다. 고단백 쌀가루의 DSC thermogram은 온도범위가 좁아지고 크기가 작아진 호화 peak를 보여주었다. 노화현상을 DSC방법과 diastase 측정방법을 이용하여 측정한 결과 DSC방법이 보다 우수함을 알았고 다수확계 삼강품종의 노화속도는 일반계 추청품종보다 빠른 것을 알 수 있었다.

• 공업화학
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• 제7권5호
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• pp.1015-1019
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• 1996

알루미나에 LiBr와 $CaBr_2$를 각각 흡착시켜 용매가 없는 상태에서 여러 가지 염화 알킬과 반응시켜 좋은 수득률로 해당하는 브롬화 생성물을 얻을 수 있었다. 이러한 높은 반응성은 알루미나에 흡착되어 있는 극소량의 물과 브롬화 금속간의 상호작용이 알루미나 상에서 일어날 수 있기 때문이라는 것을 Differential scanning calorimetry (DSC) 열분석 실험과 문헌을 통하여 고찰하였다.

• 한국작물학회지
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• 제42권3호
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• pp.344-351
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• 1997

The experiment was conducted to examine the varietal variation in gelatinization of rice flour and adaptability to rice bread processing, and the interrelation among the relevant properties. IR 44 showed the lowest temperature of gelatinization onset(T$_{o}$ ) and the highest gelatinization enthalphy(ㅿH) measured by differential scanning calorimetry (DSC). The following lower T$_{o}$ was found with the order of Suweon 230＜Pusa-33-30＜T(N) 1, Daeribbyeo 1 and the next higher ㅿ.H was followed by the order of Pusa-33-30＞Suweon 230. IRAT 177 revealed the highest temperature of gelatinization onset and conclusion(T$_{c}$) and the following higher T$_{c}$ was found with the order of Pusa-33-30＞AC 27＞Nonganbyeo. The varietal range of T$_{o}$ and T$_{c}$ was 50.0~72.5$^{\circ}C$ and 70.2~87.4$^{\circ}C$, respectively. The rice materials tested can be classified by scatter diagram on the plane of upper two principal components contracted from DSC thermogram and various characteristics relevant to processing and sensory preference of rice bread by principal component analysis. AC27, Suweonjo and IR 44 among high-amylose rices showed better suitability to rice bread processing. The temperatures of gelatinization peak and conclusion of rice flour checked by DSC were significantly negatively associated with springiness of rice bread. The most properties relevant to processing and sensory preference of rice bread such as hardness, moistness, springiness, cohesiveness, specific loaf volume and distribution or size of air cell revealed the close correlation between each other.other.

• Advances in materials Research
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• 제1권4호
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• pp.269-284
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• 2012

Thermoresponsive hydrogels based on N-Isopropylacrylamide (NIPAM) and 2-Hydroxyethylacrylate (HEA) were prepared by free radical polymerization. The hydrogels were characterized by elemental (CHN) analysis, differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). DSC thermogram showed two endothermic transitions which are due to hydration of water present in different environments. One near $0^{\circ}C$ called melting transition of ice and was used to calculate the quantitative determination of the amounts of freezing and non freezing water. The other transition above the ambient temperature was due to the combination of hydrophobic hydration and hydrophilic hydration which changes with the copolymer compositions. Swelling and deswelling studies of the hydrogels were carried out using the aqueous media, salt and urea solutions. The experimental results from swelling studies revealed that copolymers have lower rates of swelling and deswelling than the homopolymer.

• 한국축산식품학회지
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• 제20권2호
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• pp.146-151
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• 2000

The objective of this study was to investigate the characteristics on the thermal denaturation of free drip released from pork loin during chilled storage using DSC(differential scanning calorimetry). DSC thermogram of drip released from normal pork(NORD) was characterized by a minor peak and two major peaks with temperature maxima at $61.5^{\circ}C$, $71.7^{\circ}C$ (associated with sarcoplasmic proteins) and $84.3^{\circ}C$ (associated with protein-protein interaction and aggregation). In the denaturation temperature of drip released from PSE pork (PSED), the peak(Tmax) at $59.0^{\circ}C$ was reduced by $2.5^{\circ}C$. When the thermograms were divided into segments correponding to the three peaks, $\Delta$H2 was shown to be reduced by 10% in PSED as compared to NORD. With the decrease in the solubility of sarcoplasmic proteins in PSE muscle, there was a corresponding increase the drip loss during the storage.

• 한국식품과학회지
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• 제25권4호
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• pp.400-403
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• 1993

Corn starch와 waxy corn starch를 시료전분으로 사용하여 수분함량 $20{\sim}80%$ 범위에서 DSC를 사용하여 얻은 흡열곡선의 엔탈피와 효소분석법으로 전분의 호화도를 측정하여, 측정방법들 사이의 차이를 비교하여 보았다. DSC로 시료전분의 엔탈피 측정시 수분함량 70%까지는 수분함량 증가에 따라 엔탈피가 비례적으로 증가하였으나 70% 이상의 수분함량에서는 엔탈피가 평형에 도달하였으며 waxy corn starch가 4.2 cal/g, corn starch가 3.23cal/g의 엔탈피를 나타내었다. 효소분석법으로 호화도를 측정하였을 때는 수분함량의 증가에 따라 80% 수분함량까지도 시료전분의 호화도가 비례적으로 증가하였다. DSC에 의한 엔탈피 변화와 효소분석법에 의한 호화도 결과를 비교하여 보면 수분함량 70% 이하에서는 서로 직선적인 비례관계를 나타내었으나, 수분함량 70% 이상의 고 수분계 전분은 DSC로 측정시 엔탈피 차이가 나지 않았으나 효소분석법으로 측정했을 때는 수분함량 80%까지도 호화도 차이가 잘 나타났다.

• Macromolecular Research
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• 제13권2호
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• pp.156-161
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• 2005

The thermal transitions of a nylon 6/layered silicate nanocomposite were studied by differential scanning calorimetry and in-situ synchrotron X-ray diffraction. The drawn film of the nylon 6/layered silicate nanocomposite typically showed three endotherms in the DSC thermogram; a very broad endotherm at $\sim120^{\circ}C(T_{1})$, a double-melting endotherm at $\sim215^{\circ}C(T_{2})$, and a high temperature endotherm at $\sim240^{\circ}C(T_{3})$. The drawn film of the nylon 6/ layered silicate nanocomposite was comprised of a mixture of the $\alpha and \gamma$ forms, with $the \alpha form$ being generated by drawing the pressed film having $the \gamma form$. The melting and crystallization of the crystals were observed at the above thermal transitions during the heating experiment performed at the Pohang X-ray synchrotron radiation source (4C2). The newly generated form was meta-stable and melted $at {\sim}T_{1}$. The double-melting $at {\sim}T_{2}$ was due to the exothermic crystallization of $the \alpha form$ during the main endothermic melting of $the \gamma form$. $The \alpha form$ crystallized $at {\sim}T_{2}$ and melted $at {\sim}T_{3}$.

• Journal of Pharmaceutical Investigation
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• 제29권4호
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• pp.309-313
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• 1999

This study was prepared to develop the sustained release dosage form of phenylpropanolamine hydrochloride (PPA) by complexation with cation exchange resin(CER). The PPA-CER complex was confirmed by differential scanning calorimetry(DSC) thennogram, indicating a relative shift of an endometric peak of PPA to higher temperature. The loading efficiency was increased as the amount of PPA was increased as well as the time of fractional exchange was advanced as the temperatures were increased. Loading efficiency, fractional exchange, reaction rate constant and activation energy were highly dependent on the temperature and drug : resin ratio. The optimal ratio of PPA and resin was estimated to be 10: 10 for the sustained release.

• Macromolecular Research
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• 제15권3호
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• pp.234-237
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• 2007

3,4-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-4'-nitrostilbene dianhydride was prepared and reacted with 4,4'-(hexafluoroisopropylidene)dianiline to yield a novel Y-type polyimide containing the 3,4-dioxynitrostilbenyl group as an NLO-chromophore, which constituted part of the polymer backbone. The resulting polyimide was soluble in polar solvents such as acetone and N,N-dimethylformamide. The polymer exhibited good thermal stability up to $370^{\circ}C$ in the thermogravimetric analysis. The glass-transition temperature ($T_g$) obtained from the differential scanning calorimetry thermogram was near to $153^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of the poled polymer film at the fundamental wavelength of $1064\;cm^{-1}$ was around $2.15\;{\times}\;10^{-8}\;esu$ (9.01 pm/V). The dipole alignment exhibited exceptionally high thermal stability even at a temperature $30^{\circ}C$ above the $T_g$, and there was no SHG decay below $180^{\circ}C$ because of the partial main chain character of the polymer structure.

• 생명과학회지
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• 제12권2호
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• pp.121-128
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• 2002

세포막 유동성은 생체의 항상성 유지의 가장 기본적이며 중요한 기능으로서, 도라지의 용매별 분획물의 첨가로 세포막 유동성에 미치는 영향을 열시차 열량분석법 (differential scanning calorimetry, DSC)으로 측정하였다. DPPC liposome에 도라지의 용매별 분획물 첨가시 첨가물의 농도 증가에 따라 서서히 상전이 온도가 저하되었고 thermogram도 넓어졌으며 이에 따라 협동 단위($\Delta$ $H_{vH}$ /$\Delta$ $H_{cal}$)수도 감소됨을 알 수 있었다. 이는 도라지 분획물의 첨가로 DPPC liposome의 유동성이 증가하였음을 보여주는 결과로 생각 되어진다. 시료의 각 용매별 분획물의 유동성 효과는 ethyl-ether 분획층인 PGMEE의 경우 상전이온도 Tm이 시료첨가 최고농도에서 DPPC liposome 만의 경우보다 4.3$^{\circ}C$가 저하되어 다른 분획물보다 그 정도가 두드러졌으며 그 순서는 hexane 분획층 PGMH, ethylacetate 분획층인 PGMEA 및 methanol 분획층 PGMM의 순이었으며 butanol 층인 PGMB는 그 효과가 미미하여 앞서의 열역학적 요소에 거의 영향을 미치지 못했다. 이와 같은 결과는 PGMB를 제외한 시료의 각 분획물 성분 중 분자내 hydrophobicity가 큰 물질들이 DPPC liposome 이중층의 소수성부분에 더 깊숙히 침투됨으로써 인지질 liposome의 유동성을 증가시킨 현상이라고 생각된다. 도라지의 용매별 분획물의 막유동성 증가는 이온, 약물, 영양물의 흡수, 수송 및 교환등 생체막의 주요기능에 영향을 미치므로 막유동성을 증가시키는 도라지 분획물들의 생리활성물질에 대한 더욱 구체적인 연구가 기대되어 진다.