Factorize:

$16 x^{4}+54 x=2 x\left(8 x^{3}+27\right)$

$=2 x\left[(2 x)^{3}+(3)^{3}\right]$

$=2 x(2 x+3)\left[(2 x)^{2}-2 x \times 3+3^{2}\right]$

$=2 x(2 x+3)\left(4 x^{2}-6 x+9\right)$