Abstract: In many practical systems, limit cycles can be predicted with suitable precision by frequency domain methods using describing functions. Within such an approach, limit cycles can be predicted using the “eigenvalue method” [7]. This contribution presents a novel and advantageous implementation of this method, using singular value instead of eigenvalue calculations, and enhancing comput...

Oxasmaragdyrin boron complexes were prepared and applied in DSSCs. The HOMO-LUMO energy gap analyses and theoretical calculations revealed that these expanded porphyrins are ideal sensitizers for DSSCs. A device containing oxasmaragdyrin-BF2 as the sensitizer achieves an energy conversion efficiency of 5.7%.

Adomian decomposition method is extended to the calculations of the non-differentiable functions. The iteration procedure is based on Jumarie’s Taylor series. A specific fractional differential equation is used to elucidate the solution procedure and the results are compared with the exact solution of the corresponding ordinary differential equations, revealing high accuracy and efficiency. © 2...

A new approach to finite basis sets for the Dirac equation is developed. It does not involve spurious states and improves the convergence properties of basis-set calculations. Efficiency of the method is demonstrated for finite basis sets constructed from B splines by calculating the one-loop self-energy correction for a hydrogenlike ion.

in this work facile sol-gel (pechni) method has been successfully established to synthesize zn4b6o13 nanocrystals which have cubic crystals with lattice parameter: a =7.48 a. the structure and morphology of the obtained material were studied by x-ray diffraction (xrd), infrared spectra (ir), scanning electron microscopy (sem) and photoluminescence analysis. the experimental results show a band ...

the stacking mechanism of the 1h-4h proton transfer in 4-pyridone, 4-pyridinthione and p-aminopyridineare constructed. for quantitative description of this process by means of the quamtumchemicalmethod density functional theory (dft) the activation energy (

cycloaddition reaction between c30 and hula-i, 3-diene was studied within the snimework of am i (rhf)level. the reaction involving the double bond between two hexagons and a hexagon and a pentagon, as wellas the cycloaddition products followed by disrotatory ogs s electrocyclic ring openings were considered.thermodynamics parameters and stability energy and innsation state are evaluated in thre...

mndo semi-empirical scf mo calculations are used to study the pyramidal nitrogen atom inversion and configurational equilibria in the title compounds.