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Objectives: An accurate and precise spectrofluorimetric method was developed and validated for the determination of non-selective adrenergic drug named; oxymetazoline hydrochloride (OMZ) in its pure form and nasal drops. Method: Based on nucleophilic substitution reaction of target drug with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) to form a highly fluorescent fluorophore with emission measured at 543 nm after excitation at 400 nm. Results: Under optimum conditions, the proposed method obeys Beer's law in the range of (1-12 µg mL-1) and the reaction mechanism was presented. Conclusion: The method was validated according to ICH guidelines for accuracy, precision and was successfully applied for the determination of the drug in its pure form and nasal drops. The obtained results were statistically compared with those of the reported method and found to be in good agreement.

This work describes the thermal decomposition behaviour of cerium oxy-carbonate. DTA, TG, DTG and X-ray examinations were performed.The results indicate that the thermal decomposition of cerium oxy-carbonate in static air at a heating rate of l0 deg min -1 involves three steps: dehydration at 58 ~ removal of crystal water at 200 ~ and CO/release at 235 '~C.The activation energies of removal of crystal water and carbon dioxide release were found to be 59.48 and 82.33 kJ tool-t, respectively.Ceria-based oxygen ion conductors have high ionic conductivity, which makes them interesting materials for application as solid electrolytes at moderate temperature (< 600~ oxygen sensors and fuel cells [1]. The powder preparation is an important step in the fabrication of homogeneous materials. Chemical coprecipitation has been used. The properties of the final product (the sintered material or a mixed oxide powder) are largely dependent on the precipitation conditions. Precipitation as oxalate followed by calcination has been used to prepare doped oxide powders.This work describes a study of the thermal analysis and X-ray diffraction of cerium oxy-carbonate, which was prepared by precipitation from cerium nitrate solution with ammonium carbonate in the presence of ammonium hydroxide , [2].

The effects of the drying conditions on the thermal behaviour of UO3 gel microspheres were studied by TG, DTA and X-ray examination. The effects of drying with air, steam or alcohol on the crystal structure and crystallite size were also studied. The results indicate that the thermal decomposition of UO3 gel microspheres involves five steps: the first two for dehydration, the third for ammonia release, the fourth for ammonia oxidation, and the last one for UO 3 recrystallization. It was also found that the crystal growth varied from 110 A. after air drying to 512 A, and 496 ,~ after steam and alcohol treatment, respectively.

Objective: Development of simple and selective stability-indicating HPLC method for determination of tetramisole hydrochloride in presence of its degradation products. Method: Analysis was performed on SUPELCO C18 column (250mm length, 4.6mm width, 5μm particle size) using acetonitrile : methanol : water (50:33:17, by volume) as a mobile phase. The analysis process was carried out at ambient temperature with flow rate of 1 mL/min and the separated peaks were detected by UV at 212 nm. Drug was exposed to forced degradation condition like hydrolysis, oxidation, thermal and photolysis. Results: Method can well resolve all degraded product as compare to tetramisole hydrochloride. The method has been linear for the range of 1-6 μg/mL with r 2 0.9997. Conclusion: This work focused on study of the stability of tetramisole hydrochloride and its behavior when exposed to different stress conditions. The proposed method was successfully applied for determination of tetramisole hydrochloride in pharmaceutical preparation without interference from excipients or degradation products and the method was found to be valid according to International Conference on Harmonization (ICH) guidelines.

Results of DSC under isothermal conditions on the chalcogenide glass Bil0SeToIn20 are reported and discussed. The Johnson-Mehl-Avrami equation was used to evaluate the crystallization activation energy (Ea) and the crystallization mechanism was studied. The results indicate that the crystallization mechanism involves one dimensional and surface processes for Bil0SeToIn20. The average calculated value of Ea for Bil0SeToIn20 is 34.38 -+1.46 kcal/mol.Studies of kinetics are always connected with the concept of activation energy. The value of this in glass crystallization phenomena is associated with the nucleation and growth process that dominate the devitrification of most glassy solids. In general, separate activation energies must be identified with the individual nucleation and growth steps in a transformation, although they are usually combined into an activation energy representative of the overall crystallization process [1][2][3][4]. Studies of the crystallization of a glass upon heating can be performed in several different ways. In calorimetric measurements, two basic methods can be used, isothermal and non-isothermal. In the isothermal method, the sample is brought quickly to a temperature above the glass transition temperature Tg and the heat evolved during the crystallization process at a constant temperature is recorded as a function of time. In the non-isothermal method, the sample is heated at a fixed rate (a), and the heat evolved is recorded as a function of temperature or time. The crystallization process can be interpreted in terms of several theoretical models. The isothermal crystallization data are usually interpreted in terms of the Johnson-Mehl-Avrami transformation equation [4][5][6][7].

The kinetics of decomposition of gelled UO 3 microspheres has been studied by thermal analysis (DTA and TG) and by X-ray examination. UO3 microspheres prepared via/~ hydrolysis process were used in the study. The DTA and TG curves were obtained in various atmospheres at different heating rates. The activation energies for the various stages of decomposition were calculaled using the Carrol and Manche method.

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