We have performed density functional theory (DFT) calculations to investigate the properties of defect in arepresentative armchair model of silicon nanotubes (SiNTs). To this aim, the structures of pristine and defective(5,5) SiNTs have been optimized and the properties such as bond lengths, total energies, binding energies,.formation energies, gap energies, and dipole moments have been evaluat...

In this paper, the synthesis of various enaminones from the reaction of 3-aminocoumarin and ethyl-2,4-dioxo-4-arylbutanoate in the presence of p-toluene sulfonic acid is reported. The reaction was examined under different solvents and catalytic systems, which clearly proved the importance of acidic catalyst in this organic transformation. This work was also accompanied by density functional the...

viktor frankl, a neurologist and the founder of logo-therapy (1969) stated that “will to meaning” is the basic essence of the universe (1). logo-therapy means therapy through meaning, which is based on the premise that man has a will-to-meaning; the meaning thus lies in suffering(2). one of the most important human functions is discovering meaning in life, which is also considered as a sign of ...