Probing for non-statistical effects in dissociation of the 1-methylallyl radical.

Application of Chemometrics in determination of the effects of ionic and non-ionic surfactants on ac-id dissociation constant (pKa) of Meloxicam using spectrophotometric method

The purpose of this study was to determine the acid dissociation constants (pKa) of meloxicam in the presence of various surfactants including sodium lauryl sulfate (SLS) as an anionic surfactant, cetyltrimethylammonium bromide (CTAB) as a cationic surfactant and Triton® TX-100 (TX-100) as a non-ionic surfactant in different pre-determined concentrations. The related pKa was determined spec...

A Theoretical Study on the Structure-Radical Scavenging Activity of Some Hydroxyphenols

Antioxidants are made for the struggle and reconstruction of the damaged cells, because of their ability in destroying the free radicals. On account of their importance, a theoretical procedure was applied for the study of the molecular structure and radical scavenging activity of six hydroxyphenols which have been introduced as antioxidant compounds. All geometry structures were optimized by M...

Interrelationship of Smoking, Lip and Gingival Melanin Pigmentation, and Periodontal Status

Background: Cigarette smoking is a significant risk factor for periodontal disease. It also causes pigmentation of oral mucosa. The present study was aimed to assess the effects of smoking on lip and gingival pigmentation and periodontal status and the relationship between pigmentation and periodontal parameters. Methods: A total of 109 smokers and an equal number of non-smoker controls (mean a...

DFT Study of Substituent Effects on Antioxidant Activity of Kaempferol in the Gas Phase

In this work, the study of various substituted Kaempferol derivatives is presented. The bond dissociation energies (BDE) have been calculated using B3LYP level and different basis sets in gas-phase. Calculated results show that the BDE values of substituted Kaempferol range from about 77 to100 kcal/mol, demonstrating that Kaempferol is an effective chain-breaking antioxidant that prevents lipid...

Numerical Study of Non - Equilibrium Air Dissociation For Calculation of Electron Density in Hypersonic Flow