The below code will apply the cell level function to the entire column.
Dim r As Range
Set r = Intersect(ShtTemp.Columns(4), ShtTemp.UsedRange)
r.Value = Evaluate("IF(ROW(" & r.Address & "),IF(" & r.Address & "<>"""",UPPER(" & r.Address & "),""""))")
r.Value = Evaluate("IF(ROW(" & r.Address & "),IF(" & r.Address & "<>"""",TRIM(" & r.Address & "),""""))")
Dim r As Range
Set r = Intersect(ShtTemp.Columns(4), ShtTemp.UsedRange)
r.Value = Evaluate("IF(ROW(" & r.Address & "),IF(" & r.Address & "<>"""",UPPER(" & r.Address & "),""""))")
r.Value = Evaluate("IF(ROW(" & r.Address & "),IF(" & r.Address & "<>"""",TRIM(" & r.Address & "),""""))")