• Archives of Pharmacal Research
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• v.27 no.3
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• pp.357-360
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• 2004

Four crystal forms of ketorolac have been obtained by recrystallization in organic solvents under variable conditions. Different ketorolac polymorphs and pseudo polymorph were characterized by X-ray powder diffraction crystallography (XRD), Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In the dissolution studies in water at $37{\pm}0.5^{\circ}C$ four crystal forms showed different patterns. The solubility of Form I were the highest. The solubility decreased in rank order: Form I> Form II > Form III > Form IV. Form land Form III were shown to have a good physical stability at room temperature for 60 days. However, Form II is converted to Form III and Form IV is converted to Form I after 60 days storage. Therefore, these observations indicate that crystalline polymorphism for ketorolac is readily inter-convertible and the relationship may have to taken into consideration in the formulation of the drug.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.05a
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• pp.126-131
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• 1993

Differential Scanning Calorimetry (DSC) and solvent swelling technique have been applied for identifying physical transition temperatures in the macromolecular structure of coals. The transition processes seem to be associated with physical relaxation of the coal structure and are irreversible processes. In Pittsburgh No. 8 high volatile bituminous (hvb) coat one physical transition was noted at 250-30$0^{\circ}C$ (at 8$^{\circ}C$/min) without any significant accompanying weight loss. Coals of higher rank than high volatile bituminous, i.e., Upper Freeport medium volatile bituminous (mvb) and Pocahontas No.3 low volatile bituminous (lvb) coals, exhibit structural relaxation just before the major thermal decomposition process and a sharp increase in solvent swellability accompanies this relaxation. In the case of both the Pittsburgh No.8 and the Upper Freeport coat structural relaxations at around 36$0^{\circ}C$ seem to coincide with release of "guest molecules".les".uot;.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.55-62
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• 1983

Four of non- isothermal methods evaluating kinetics have been studied by using differential scanning calorimetry (DSC) and thermogravimetry (TG) and applied for kinetics of the thermal decomposition of cellulose. It is concluded that the heating evolution methods with DSC and approximative methods with TC can lead to satisfactory kinetic analysis. Results calculating the reacting order and the activation energy of cellulose decomposition were 1/2 order and 42kcaB/mol, respectively.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.91-96
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• 2000

Glass fiber reinforced thermoplastic composites were manufactured by Rapid Press Consolidation Technique(RPCT) as functions of temperature, pressure and time in pre-heating, consolidation and solidification sections during the manufacturing processing. It was found that the material property is greatly affected by pre-heating temperature under vacuum, mold temperature and molding pressure. Among them, the temperature In the mold was the most critical factor in determining the mechanical properties and the molded conditions of specimen. The crystallinity of PET matrix was also investigated by differential scanning calorimetry(DSC) measurements for various processing conditions. The level of crystallinity($X_c$) depended strongly on the mold temperature, cooling rate and the type of composite. The difference in $X_c$ is believed to be one of important factors in characterizing the mechanical properties.

• Macromolecular Research
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• v.14 no.6
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• pp.588-595
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• 2006

The morphology, structure and melting behaviour of cold-crystallized isotactic polystyrene (iPS) were studied by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS). The polymer was found to crystallize according to the dual-lamellar stack model. The two populations of lamellae, along with a melting-recrystallization phenomenon, determined the appearance of multiple melting peaks in DSC traces. The annealing peak was attributed to the relaxation of a rigid amorphous phase, rather than to the melting of crystalline material.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1262-1266
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• 2009

Thermodynamics of the interaction between Cerium (III) chloride, $Ce^{3+}$, with Human Serum Albumin, HSA, was investigated at pH 7.0 and $27\;{^{\circ}C}$ in phosphate buffer by isothermal titration calorimetry. Our recently solvation model was used to reproduce the enthalpies of HSA interaction by $Ce^{3+}$. The solvation parameters recovered from our new model, attributed to the structural change of HSA and its biological activity. The interaction of HSA with $Ce^{3+}$ showed a set of two binding sites with negative cooperativity. $Ce^{3+}$ interacts with multiple sites on HSA affecting its biochemical and biophysical properties.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2154-2164
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• 1995

In this study, a dielectric cure monitoring system which consists of an electric circuit, a sensor and a personal computer was developed to on-line monitor the dielectric properties of carbon fiber epoxy composite materials. Also, the kinetic model of carbon fiber epoxy composite materials was developed by curve fitting of differential scanning calorimetry data. The start and end points of cure and the relationship between the dissipation factor and the degree of cure were obtained by comparing the dissipation factor from the dielectric properties with the degree of cure from the DSC data. The relationship between the dissipation factor and the degree of cure was tested under various temperature profiles.

• Journal of Pharmaceutical Investigation
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• v.19 no.2
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• pp.109-116
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• 1989

Solid dispersion of fenticonazole nitrate (FN) with poloxamer 407, polyethylene glycol 6000, povidone (K-90) were prepared by the solvent method. To characterize the state of the drug in solid dispersions, the x-ray diffractometry and differential scanning calorimetry were carried out. The identification of these systems suggested that FN in the poloxamer 407 system remained in crystalline state, and the drug in the PVP system was amorphous. A marked increase in the dissolution rate of FN was attained by dispersing the drug in the hydrophilic polymers used, and the dispersion with poloxamer 407 was superior to the other two carriers in releasing the drug into solution.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1564-1569
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• 2004

Insulating a heat from the environment is the most important in cryogenic applications like HTS cable system. Vacuum and MLI(Multi-Layer Insulation) have been widely used to get highly efficient cryogenic insulation. In this study, experiment on annular cylinder regarded as basic model of HTS cable cryostat has been performed to measure the heat loads. To investigate the effectiveness of radiation shields in cryogenic insulation system, the experiments are carried out to various number of the shields. The measured values are compared with the results estimated theoretically. The heat loads invaded from the environment was determined by liquid nitrogen boil-off calorimetry.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1223-1229
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• 2001

Though conventional calorimetry methods such as differential scanning calorimetry (DSC) and differential thermal analysis (DTA) are used generally in measuring heat of fusion, T-history method has the advantages of a simple experimental apparatus and no requirements of sampling process, which is particularly useful for measuring thermal properties of inhomogeneous phase change materials (PCMs) in sealed tubes. However, random criteria (a degree of supercooling) used in selecting the range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion. In the present study, it was shown that a 40% discrepancy exists between the original T-history and the present methods when analyzing the same experimental data. As a result, a reasonable modification to the original T-history method is proposed.