undoped and mn-doped zno nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. structural, chemical and optical properties of the samples were studied by x-ray diffraction (xrd), field emission scanning electron microscopy (fesem), uv-vis spectrophotometry and fourier transform infrared (ft-ir) spectroscopy. the phase purity was con...

Characteristic solutions to Maxwell's equations, constrained to equivalence classes by constitutive equations that have certain crystal symmetries, are represented by phase 1-forms, k, such that both 3-forms vanish: k^F = 0 and k^G = 0: Simple examples are given which show the di®erences between Faraday rotation where the 3-form of Topological Torsion is not zero, A^F 6= 0, and Optical Activity...

In this research, Zn2SnO4 nanorods were prepared and structural properties of the nanorods were characterized, developing of wide-range of the optical behavior of Zn2SnO4 nanorods and the antibacterial activity was also investigated using a microwave-assisted method. A zinc stannate (Zn2SnO4) nanorod was synthesized via facile microwave-assisted method using ammonia with cubic spinel structure....

HE question of the origin of petroleum has long been debated. In the history of this question, the fact of the optical activity of petroleum has occupied an important place. It was pointed out ( 1 , 2 ) by Walden that "inorganic" hypotheses for explaining the origin of petroleum did not account for its optical activity. Because of the increasing certainty that all petroleums possessed optical a...

To the Editor — The relationship between chirality and optical activity is an important consideration for various fields of chemical, physical and biological research. For example, the determination of optical activity is a routine test of enantiomeric purity in organic synthesis. Chiral materials (or other non-centrosymmetric (NCS) materials) are also commonly used in optics and photonics to c...

We review the variety of Active Galactic Nuclei (AGN) classes (so-calledAGN zoo") and classification schemes of galaxies by activity types based on their optical emission-line spectrum, as well as other parameters and other than optical wave-length ranges. A historical overview of discoveries of various types of active galaxies is given, including Seyfert galaxies, radio galaxies, QSOs, BL Lace...