摘要
In this paper we present the non-singlet QCD analysis to determine valence quark distribution up to four loop.We obtain the fractional difference between the 4-loop and the 1-,2and 3-loop presentations of xu v （x,Q^2） and xd v （x,Q^2）.
In this paper we present the non-singlet QCD analysis to determine valence quark distribution up to four loop.We obtain the fractional difference between the 4-loop and the 1-,2and 3-loop presentations of xu v （x,Q^2） and xd v （x,Q^2）.
