In this scientific research, MnO2 nanoparticles (NPs) have been successfully prepared by a precipitation method using KMnO4, MnSO4.H2O and H2O2 (30%) as the precursors. As-prepared sample was identified by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Infrared (IR) techniques. The transmission electron microscopy (TEM) showed 7-8 nm rang...

The analysis of observed structure factors estimated after Rietveld analysis by the maximum-entropy method (MEM) gives electron or nuclear densities in the unit cell. The resultant densities are, more or less, biased toward a structural model in the Rietveld analysis. To overcome such a problem, we devised a sophisticated technique named MEM-based pattern fitting (MPF). For this purpose, a patt...

D. Direct Nuclear Spin-Spin Interactions in Free Molecules. Internuclear Spacings and Shapes of Molecular Vibrational Potential IS. Direct Nuclear Spin-Spin Interactions in Rigid Solids. Atomic Spacings and Bond Angles F. Nuclear Paramagnetic Resonance Line Widths in Liquids and Gases Collision Narrowing G. The Effect of Nuclear Motion on Nuclear Resonance Spectra in Crystals. Hindered Rotatio...

of nuclear graphite in Generation-IV, prismatic Very High Temperature and High Temperature gas cooled Reactors (VHTRs and HTRs) in the unlikely event of a massive air ingress accident. The completed research tasks include: (a) Developing and validating a modeling capability, based on chemical reactions kinetics, for the gasification rates of nuclear graphite as functions of temperature, oxygen ...

Nuclear Security aims at the prevention and detection of and response to, theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving nuclear material". Nuclear Forensics is a key element of nuclear security. Nuclear Forensics is defined as a methodology that aims at re-establishing the history of nuclear material of unknown origin. It is based on indicators that ar...

Nuclear stiffness, expressed as a hardness derivative, appears to be a good measure of the slope of global hardness. The authors analyze molecular states for which hardness has a maximum value. Maximum hardness principle (MHP) has been discussed. At the ground state hardness function does not obtain a maximum value versus spatial coordinates within a constant number of electrons (N), but is so ...

The 13C nuclear spin-lattice relaxation time Tl was studied in liquid CSa from -106°C to +35X! at resonance frequencies of 14, 30, and 62 MHz. The relaxation is caused by anisotropic chemical shift and spin-rotation interaction. It is shown that for linear molecules the spin-rotation constant C and the anisotropy of the chemical shift Aa can be obtained from the relaxation rates without use of ...

Many of the properties of massive stars in external galaxies, such as chemical compositions, mass functions, and ionizing fluxes, can be derived from the study of the associated clouds of ionized gas. Moreover, the signatures of Wolf-Rayet stars are often detected in the spectra of extragalactic H ii regions. This paper reviews some aspects of the recent work on the massive star content of near...