Fast and simple hydrophilic interaction liquid chromatography (HILIC) method was developed and validated for the analysis of moxonidine and its four impurities (A, B, C, and D) in pharmaceutical dosage form. All experiments were performed on the Agilent Technologies 1200 high-performance liquid chromatography (HPLC) system using Zorbax RX-SIL, 250 mm × 4.6 mm, 5 μm column as stationary phase (T...

Simvastatin is used in treatment of hypercholesterolemia because it regulates cholesterol synthesis as a result of its β-hydroxy acid acting as an inhibitor of 3-hydroxy-methylglutaryl coenzyme A (HMG-CoA). The present communication deals with synthesis, characterization and development of accurate, precise and sensitive Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method for ...

Degradation pathway for eplerenone is established as per ICH recommendations by validated and stability-indicating reverse phase liquid chromatographic method. Eplerenone is subjected to stress conditions of acid, base, oxidation, and thermal and photolysis. Significant degradation is observed in acid and base stress conditions. Four impurities are studied and the major degradant (RRT about 0.3...

In this paper, the effect of the structural properties and morphology of iron oxide product, have been studied in co-precipitation and hydrothermal methods. Also, the effect of adding CCl4 impurities and final annealing of the materials is taken into account. The more homogeneous particle size in hydrothermal method has been explained by the effect of adding CCl4 as impurities to prevent the co...

We study the embrittlement of Ni due to the presence of S impurities, considering their effect in the bulk and at grain boundaries (GBs). For bulk Ni, we employ Rice’s theory based on generalized-stacking-fault energetics and the unstable stacking energy criterion. We use first-principles density-functionaltheory calculations to determine the ductility parameter D = γs/γus, the ratio of the sur...

Tokapole II is a tokamak with a four-node poloidal divertor. Impurity concentrations, line radiated power, and impurity behavior have been studied in Tokapole II discharges with two VUV spectrometers, o one of which acquires the VUV spectrum (400-1300 A) with a single discharge. Oxygen (3-5% of the electron density) is the dominant �lpurity, and the measured total radiated power is 15-30% of th...

The structure and aggregation kinetics of diffusion-limited cluster-cluster three-dimensional monomeric aggregates and gels is investigated as a function of the molar fraction of two types of impurities. In one case the impurities are allowed to aggregate among themselves whereas in the other the impurities are mobile monomers that remain as such during the whole aggregation process. Computer s...

Impurities are often driven to segregate to grain boundaries, which can significantly alter a material's thermal stability and mechanical behavior. To provide a comprehensive picture of this issue, the influence of a wide variety of common nonmetallic impurities (H, B, C, N, O, Si, P and S) incorporated during service or materials processing are studied using first-principles simulations, with ...

This work was aimed at reproducing experimental results in impurity compression of Ar, as well as the screening of recycling and non-recycling impurities from reaching the core plasma. As part of the study the code was upgraded in order to track the impurity flow from source till it reaches the core, include the energy dependence on recycled impurity atoms, and allow for more realistic impurity...

We use a quantum lattice gas model to describe essential aspects of the motion of He atoms and of He impurities in solid He. This study suggests that He impurities bind to defects and promote He atoms to interstitial sites which can turn the bosonic quantum disordered crystal into a metastable supersolid. It is suggested that defects and interstitial atoms are produced during the solid He nucle...