• Journal of Pharmaceutical Investigation
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• v.32 no.2
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• pp.81-85
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• 2002

Three polymorphic modifications of CKD-602, water soluble derivative of camptothecin, were obtained by the recrystallization from different organic solvents and characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray powder diffraction (XRPD). The major endothermic peaks of the DSC curve of Form 1, Form 2 and Form 3 was shown at $268.71^{\circ}C$, $247.83^{\circ}C$, $244.76^{\circ}C$, respectively. Form 2 was elucidated to be an acetic acid solvate and Form 3 was elucidated to be a methanol solvate. The dissolution patterns of these three modifications were also checked in distilled water at $37{\pm}0.5^{\circ}C$, for 30 minutes. The polymorphic modifications showed differences in the dissolution rate. The dissolution rate of Form 1 was faster than that of other polymorphic modifications. When stored at different relative humidity over the period of 3 months, all of the polymorphic modifications did not undergo transformation.

• Journal of Environmental Health Sciences
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• v.29 no.4
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• pp.48-54
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• 2003

This study investigated retrogradation properties of Jeungpyun substituted for cereals with dietary fibers of 60% of brown rice, and barley. Quality changes during storage periods of the functional Jeungpyun, were studied using $\alpha$-amylase iodine enzyme digestion methods, X-ray diffraction patterns, and differential scanning calorimetry (DSC). The barley substituted samples showed significantly lower retrogrdation rates than those of control when examined by $\alpha$-amylase method. The Relative crystallity by X-ray diffraction patterns had typical A type in all samples with appealing big crystallity around its diffraction angle 23$^{\circ}$degrees as storage periods were increased. The brown rice and barley Jeunpyun made smaller crystallity than that of control, representing slower retrogradation rates. The batter controls had significantly lower ΔH than the other compared samples when measured by DSC, but had significantly higher ΔH after 30 days of storage, implying that the control required more energy for regelatinization after the 30 days of storage.

• Advances in materials Research
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• v.1 no.4
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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.

• Food Science of Animal Resources
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• v.20 no.2
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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.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.145-148
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• 2011

The thermal behavior of lithiated Si anodes has been investigated using differential scanning calorimetry (DSC). In particular, the effect of Si particle size on the thermal stability of a fully lithiated Si electrode was investigated. For DSC measurements, a lithiated Si anode was heated in a hermetically sealed high-pressure pan with a polyvinylidene fluoride (PVDF) binder and a 1 M $LiPF_6$ solution in an ethylene carbonate (EC)-diethyl carbonate (DEC) mixture. The thermal evolution around $140^{\circ}C$ increases with lithiation and with decreasing particle size; this phenomenon is attributed to the thermal decomposition of the solid electrolyte interface (SEI) film. Exothermic peaks, following a broad peak at around $140^{\circ}C$, shift to a lower temperature with a decrease in particle size, indicating that the thermal stability of the lithiated Si electrode strongly depends on the Si particle size.

• Journal of the Korean Chemical Society
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• v.63 no.1
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• pp.7-11
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• 2019

Olmutinib, N-[3-({2-[4-(4-methylpiperazine-1-yl)aniline]thieno[3,2-d]Pyrimidin-4-yl}oxy)phenyl]prop-2-enamide dihydrochloride monohydrate, $Olita^{TM}$ is an oral, third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) that was developed by Boehringer Ingelheim and Hanmi Pharmaceutical Co. Ltd for the treatment of non-small cell lung cancer (NSCLC). The aim of this work was to investigate the existence of polymorphs and pseudopolymorphs of olmutinib. Three crystal forms of olmutinib have been isolated by recrystallization and characterized by differential scanning calorimetry (DSC), thermogravimetric (TG) analysis and powder X-ray diffractometry (PXRD). From the DSC and TG data it was confirmed that Form 1 is monohydrate, Form 2 is dihydrate, Form 3 is 1.5 hydrate. The PXRD patterns of three crystal forms were different respectively. After storage of 1 month at $2^{\circ}C$, 24% RH (Relative Humidity), Form 1, Form 2, and Form 3 were not transformed.

• Journal of the Korean Society of Combustion
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• v.16 no.3
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• pp.21-26
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• 2011

Thermal analyses are conducted to measure chemical kinetic parameters of an unknown liquid fuel with various components. Thermal Analyses are divided into two different methods such as TGA(Thermo-Gravimetric Analysis) and DSC(Differential Scanning Calorimety). Non-isothermal experimental results are analyzed by adopting TGA and they are filtered by Freeman-Carroll method. As a results of the analysis, chemical parameters of the activation temperature and the reaction order are measured to be 6128.2 K and 1.4, respectively. Furthermore, the chemical kinetic parameters are obtained by a variety of mathematical processing methods. It has been found that they show a little difference depending on the processing method.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.305-314
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• 2002

The dehydration of hexadecyltrimethylammonium (HDTMA)-exchanged montmorillonite has been studied using X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The dehydration in HDTMA-montmorillonite seems to influence the swelling behavior of the organo-clay during heating. The basal d(001) spacing vs temperature curve of the HDTMA-montmorillonite has one broad swelling edge with a shoulder on the low-temperature side. We believe that the shoulder at $100^{\circ}C$ for the HDTMA-montmorillonite is due to interlayer swelling induced by the initial rearrangement of surfactants, and the second edge at $200^{\circ}C$ is caused by interlayer swelling resulting from the secondary vertical reorientation of alkyl chains. It seems that the dehydration of organo-clay induces a reorientation of the alkyl chains by transition to more vertical position relative to the silicate sheets, allowing instantly greater d-spacing.

• Electrical & Electronic Materials
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• v.8 no.4
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• pp.478-486
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• 1995

Cu/NbTi multilayer thin films and superconducting wires were fabricated and heat treated with conventional annealing and analyzed by differential scanning calorimetry (DSC) as a basic study for the enhancement of Jc. Interfacial reactions of Cu/NbTi multilayer thin films and superconducting wires were investigated with optical microscope, SEM, and XRD. According to the effective heat of formation (EHF) model, CU$\_$3/Ti was predicted as a first phase. However, considering the crystalline structure and thermodynamics, CuTi was predicted as a first phase. According to the results of DSC and XRD, CU$\_$2/Ti was found to be the first phase, followed by the formation Of CU$\_$4/Ti. The difference in first crystalline phase between the experimental result and the predicted one was discussed. In case of Cu/NbTi superconducting wires, the compounds formed at the Cu/NbTi interface grew with annealing time and the amount of compounds formed in Nb-47wt%Ti alloy was larger than that in Nb-50wt%Ti alloy. It seemed that the incubation time for the formation of compounds in Nb-50wt%Ti alloy was longer than that formed in Nb-47wt%Ti alloy. Also, the diffusion was the rate controlling step for the growth of compounds in all specimens. These compounds were formed at 500-600.deg. C for I hour annealing and, thus, the drawing time below I hour must be required to minimize the growth of compounds for the enhancement of Jc.

• Polymer(Korea)
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• v.34 no.5
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• pp.480-484
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• 2010

A series of poly(amic acid)s(PAAs) was prepared by reacting 4,4'-(4,4'-isopropylidenediphenoxy) bis(phthalic anhydride)(BPADA) as the anhydride monomer and 2,2'-bis(trifluoromethyl) benzidine (TFB), bis(3-aminophenyl)sulfone (APS), 4,4'-methylenebis-(2-methylcyclohexylamine) (MMCA), or bis[4-(3-aminophenoxy) phenyl] sulfone (BAPS) as the amine monomer with 5 mol% melamine in N,N-dimethylacetamide (DMAc). Colorless and transparent polyimide (PI) films were obtained by casting the PAAs at various heat treatment temperatures. The thermo-mechanical properties and optical transparency of the PI films were investigated. The thermal properties of the PI films were examined using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and thermomechanical analysis (TMA), and their optical transparency were measured by spectrophotometry. The coefficient of thermal expansion (CTE) and yellow index (YI) values of all samples were in the range of $48.53-64.24ppm/^{\circ}C$ and < 3.0, respectively.