The multichannel R-matrix code is employed to compute the collision strengths for electron-impact excitation of pentacid Mg ion.

Electron collision strengths for 1s-2s and 1s-2p transitions of hydrogen-like He+, Li2+ ions have been calculated using closed-coupling R-matrix method.

In this methods, by using the MCDF wave functions to describe the target-ion states, and the relativistic continuum wavefunctions to describe scattering electron states, the contributions of relativistic and correlation effects on collision strengths and rate coefficients are included automatically in the calculations.

The collision strengths and rate coefficients of U 91+ ion are computed with this method.

The R matrix approximation is used to compute the excitation collision strength of electron impact on Li like C with the configuration interaction wavefunctions, in which the configuration interactions of an inner shell electron excitation are included.

With the optimized CI wavefunctions, the excitation collision strengths between the states of configurations .

The effects of different temperatures on compressive strength and bulk density were studied.

A test is done on pre-baked anode made from calcined coke in aspects of apparent density,real density,porosity,resistivity of powder,compressive strength,which shows compressed petroleum coke improves its chemical and physical performances.

In order to save the required energy for grinding the slag, the compressive strength of the slag is reduced by inducing cracks in it with the help of microwave.