Starting from the QCD potential which emerges from the effective dilaton gluon coupling,the energy levels and the widths of the leptonic decay and radiative transition are calculated for heavy mesons(c and b)and compared with that of the Cornell potenial.

The relation between the leptonic decay width of J / ψand the color screening mass at finite temperature is studied by using different quark binding potentials.

The spectra,leptonic decay widths and the E1 transitions of system are calculated,with the confining potential including the color screening effect as a color confinement between quark and antiquark.

We study the decay widths of the narrow resonances D*sj(2317) and Dsj(2460) in the chiral quark model, together with the well-known D* and D*s mesons.

The decay width is agreement with the result of standard light-cone QCD sum rules in the range of error margin.

We calculate the correction to the two gluon decay width for η\-c due to the finite extension of the vertex function.

Using these operators, we estimate the decay widths of the neutral vector meson ρ in a realistic one family TC (Technicolor ) model and discuss the possibility of detecting this particle at pp colliders or at LEPⅡ.

We have presented a calculation for the total and partial decay widths for vibrational predissociation for a low vibrational excited van der Waals molecule HeI_2.