Steenrod operations on bar complex

We define a chain map of the form $\E(k)\otimes BA^{\otimes k}\longrightarrow BA$,where$\E$isacombinatorial$E_\infty$-operad called the sequence operad, and $BA$ is the bar complex of an $\text{E}$-algebra $A$. We see that Steenrod-type operations derived from the chain map are equal to the corresponding operations on the cohomology of the based loop space under an isomorphism.