• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.5
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• pp.15-21
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• 2015

The thermal decomposition characteristics of the ZPP(Zirconium/Potassium perchlorate), widely used as a primary charge of initiators, were investigated by differential scanning calorimetry(DSC). The DSC results with different heating rates were elaborated with AKTS-Thermokinetics software for the determination of the kinetic parameters of the thermal decomposition of ZPP. There was good agreement between the experimental and the simulation curves, based on the determined kinetic parameters, which indicates the validity of the kinetic description of the thermal decomposition process of ZPP.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.69-72
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• 2010

This study explored the solid fat index (SFI) of structured lipids (SLs) synthesized by lipase-catalyzed (Lipozyme TLIM) interesterification using hydrogenated coconut oil (HCO), palm oil (PO) and palm stearin solid (PSS). SLs were produced using three blends of HCO/PO (60:40, w/w), HCO/PSS (40:60 and 60:40, w/w), and HCO/PO/PSS (32:48:18, w/w/w) to find a desirable confectionary fat by monitoring melting and crystallization behaviors of SFI of SLs using differential scanning calorimetry (DSC). SFI of HCO/PSS (60:40) and HCO/PO/PSS (32:48:18) at $25^{\circ}C$ were 70% and 68%, respectively. These results suggest that HCO/PSS (60:40) and HCO/PO/PSS (32:48:18) may be useful as potential SLs of a confectionary fat.

• Applied Chemistry for Engineering
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• v.5 no.6
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• pp.967-974
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• 1994

We studied the cure kinetics of the DGEBA(Diglycidyl ether of bisphenol A)/MDA(4, 4' -methylene dianiline)/MN(Malononitrile)/HQ(Hydroquinone) system by Barrett method and Integral method with dynamic runs of differential scanning calorimetry(DSC). Kinetic parameters such as activation energy and pre-exponential factor were obtained and reaction order was estimated roughly supposing that present system was adjusted to nth order reaction. The MN(Malononitrile) was introduced as a chain extender and HQ(Hydroquinone) as a reactive accelerator or catalyst.

• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.417-424
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• 2004

Polycarboxylate type superplasticizers (PCA) with different graft chain (Polyethylene oxide) length were synthesized by Methoxypoly (ethyleneglycol)monomethacrylate (MPEGMAA) and methacrylic acid (MAA). The effects of PCA on the hydration of Ordinary Portland Cement (OPC) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. The effect of graft chain length of PCA on the hydration of OPC was different at early age, but, at long age, was similar. The ratio of relative peak intensity, (I［001］/I［101］), of Ca(OH)$_2$ compared with OPC also was reduced by PCA addition.

• BMB Reports
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• v.35 no.4
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• pp.364-370
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• 2002

The effect of sodium n-dodecyl sulphate (SDS) on hemoglobin autoxidation was studied in the presence of a 100mM phosphate buffer (pH 7.0) by different methods. These included spectorphotometry, fluorescence technique, cyclic voltametry, differential scanning calorimetry, and densitometry. Spectroscopic studies showed that SDS concentrations up to 1 mM increased deoxy-, decreases oxy-, and had no significant effect on the met- conformation of hemoglobin. Therefore, a SDS concentration up to 1 mM increased the deoxy form of hemoglobin as the folded, compact state and decreases the oxy conformation. The turbidity measurements and differential scanning calorimetry techniques indicated a more stable conformation for hemoglobin in the presence of SDS up to 1mM. Electrochemical studies also confirmed a more difficult oxidation under these conditions. The induction of the deoxy form in the presence of SDS was confirmed by densitometry techniques. The compact structure of deoxyhemoglobin blocks the formation of met-conformation in low SDS concentrations.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.300-310
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• 1994

Physicochemical properties for the inclusion complex of chenodeoxycholic acid(CDCA) and it's $7{\beta}-hydroxy$ epimer ursodeoxycholic acid(UDCA) with ${\beta}-cyclodextrin({\beta}-CyD)$ were studied. The formation of the complex in the solid state were confimed by polarized microscopy and differential scanning calorimetry(DSC). Proton nuclear magnetic resonance$(^1H-NMR)$spectroscopy showed that CDCA and UDCA form an inclusion complex with ${\beta}-CyD$ in aqueous solution. The 1 : 1 stoichiometry of the complex was dextermined by the continuous variation method. From DSC and $^1H-NMR$ studies, there were not any differences between CDCA and UDCA. Complex of CDCA and UDCA showed increase in solubility and dissolution compared with CDCA and UDCA alone, respectively. Solubility pattern of UDCA complex was pH independent but, CDCA complex was like that of CDCA. Dissolution rate increased markedly in case of UDCA complex compared with CDCA complex, especially in acidic pH value.

• Journal of the Korean Applied Science and Technology
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• v.24 no.4
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• pp.416-426
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• 2007

Polypropylene (PP) composites with wood flour/wax/coupling agent were manufactured by melt compounding and injection molding. The influence of wood flour(WF), wax, and coupling agent on the mechanical and thermal properties of the composites was investigated. The addition of wood flour to neat PP has the higher tensile modulus and strength compared with neat PP. The presence of wax also improved the tensile modulus. At the same loading of PP and WF, the addition of coupling agent highly decreased the tensile modulus, and increased the tensile strength. From thermogravimetric analysis (TGA), the addition of wax improved the thermal stability of the composites in the later stages of degradation. The presence of MAPP and wood flour in turn decreased thermal stabilities of composites. From differential scanning calorimetry analysis (DSC), neither the loading of wax. nor the presence of MAPP has shown significant effect on the thermal transition of composites.

• Composites Research
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• v.14 no.2
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• pp.33-42
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• 2001

The cure kinetic equation fur 52-glass/polyester prepreg composites was established through DSC (differential scanning calorimetry). Using the established kinetic equation, the temperature distribution of the thick composite was calculated considering the change of heat transfer resistance due to resin impregnation of bleeder plies used. In order to reduce the overheat during cure of thick glass fiber composites, the cure cycle was modified by introducing the cooling and reheating steps. Then the thick glass composites were cured both by the conventional cycle without any cooling or reheating step and the modified cure cycle. The mechanical properties of the thick composites cured by the both cycles were tested by the short beam shear test and the Barcol hardness test, and then their results were compared.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.185-194
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• 2007

This study was performed to evaluate the physicochemical, sensory evaluation of Backsulgi changed with germinated brown rice flour(GBRF) at different ratio. Moisture content decreased gently during storage and the decrease was less in GBRF-added groups than the control group. The color L value decreased significantly by with increasing the GBRF, wherease the redness(a) and yellowness(b) were both increased. As the result of measurement with texture analyzer, hardness, gumminess, chewiness, adhesiveness and fracturability of Backsulgi tended to decrease in proportion to the amount of GBRF in the formula. The thermal properties of Backsulgi were investigated by differential scanning calorimetry(DSC). Onset temperature and peak temperature of gelatinizatino in thermal characteristics showed low in case of addition of GBRF into Backsulgi. All samples changed with GBRF had low values in change of melting enthalphy. In the sensory evaluation, Backsulgi with GBRF were superior in flavor, cohesiveness, hardness, chewiness and moistureness than that of control. And Backsulgi with 20% GBRF showed the highest score in overall acceptability. Therefore we concluded that the addition of GBRF on Backsulgi improve the sensory characteristics as well as delay the retrogradation.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.237-240
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• 1998

The application of a low calorie sweetener, tagatose, to chocolate product was investigated. The viscosity of chocolate prepared with tagatose were almost the same as that of chocolate with sucrose. The melting point and endothermic enthalpy of chocolate prepared with tagatose, which were obtained from the analysis of differential scanning calorimetry, were also almost the same as those of chocolate with sucrose. However, chocolate with tagatose was softer than that of chocolate with sucrose.