Validated Stability Indicating Method for Determination of Indapamide in Pharmaceutical Formulation

A stability indicating method for Indapamide in an oral antihypertensive tablet and bulk dosage forms was developed and validated by reverse phase HPLC (RP-HPLC). The proposed RP-HPLC Shisheido Capcell Pak C18 column was used and column dimension was 250mm × 4.6mm i.d., 5μm partical size at ambient temperature. The mobile phase Methanol and Phosphate Buffer pH 5.8 (60:40) was run in isocratic mode at a flow rate of 1.0ml/minute. The wavelength of Indapamide was selected at 241nm. Indapamide was found as single peak in the chromatogram at 6.58 min. The different chromatographic conditions were applied to determine the drug in pharmaceutical dosage form. The linearity of the proposed method was found in a range of 0.2-1.2μg/ml with coefficient of correlation (r2) value 0.999, slope 8360 and intercept -77.78. The percent RSD of intraday precision and interday precision were found in range of 0.498 - 1.661 and 0.882 - 1.623 respectively. The average accuracy of the method at three different levels of 50, 100 and 150 % were found to be 100.67, 99.50 and 100.65, respectively. The LOQ and LOD expressed as signal to noise ratio (S/N) were found to be 0.03 and 0.08μg/mL with good accuracy and precision. Indapamide was exposed to different stress conditions like alkaline, acidic, thermal, oxidative and photolytic. The stressed samples were analyzed by the proposed method. The proposed methods can be used for routine analysis stability testing and assay of Indapamide in quality control laboratories.

A Fractional-in-Time Prey–Predator Model with Hunting Cooperation: Qualitative Analysis, Stability and Numerical Approximations

A prey–predator system with logistic growth of prey and hunting cooperation of predators is studied. The introduction of fractional time derivatives and the related persistent memory strongly characterize the model behavior, as many dynamical systems in the applied sciences are well described by such fractional-order models. Mathematical analysis and numerical simulations are performed to highlight the characteristics of the proposed model. The existence, uniqueness and boundedness of solutions is proved; the stability of the coexistence equilibrium and the occurrence of Hopf bifurcation is investigated. Some numerical approximations of the solution are finally considered; the obtained trajectories confirm the theoretical findings. It is observed that the fractional-order derivative has a stabilizing effect and can be useful to control the coexistence between species.

METHODOLOGICAL ASPECTS OF INDUSTRIAL ENTERPRISE PRODUCTION POTENTIAL

This article discusses the need for organizations to comply with a number of principles for successful functioning in the modern economy and lists these principles. The authors also considered ways to evaluate the organization's activities, the importance of taking into account basic, intermediate and resulting data to carry out a comprehensive analysis, and briefly described the logical mechanism that ensures the leading value of the production potential in assessing the activities of the enterprise. In addition, the authors considered and described the following principles that are characteristic of the economic content of the production potential as a system: integrity, complexity, interchangeability of components, flexibility, reliability, safety, self-consistency, optimality, stability, etc. The specificity of the level of the production potential as an indicator in the system analysis (stability for positive and high influence for negative impacts) was described. The authors also mentioned and described the most important indicators for the prediction of capabilities and economic boundaries of the enterprise's potential.

An Application of Reinforced Polyurethane Foam in Design of the Common Bulkhead for Cryogenic Tanks

By using the material of reinforced polyurethane (RPU) foam, the common bulkhead is devised for cryogenic tanks in this paper. Properties of RPU foam are obtained through experiments. Based on the properties, the structure is designed with the integration of special features including lightweight, easy to manufacture, load bearing and thermal insulation. Based on numerical simulation, thermal analysis, stability and thermal mechanical coupling behavior of the structure are analysed. The results show that the common bulkhead not only satisfies the heat insulation requirements of cryogenic tanks for liquid hydrogen and oxygen, but also keeps stability.