Qthread,adding function to qthread

I have a class like that

class Class1 : public QObject
{
    Q_OBJECT
    void a();
    void b();
    ...........

void Class1:a()
{
    for(int i=0;i<10;i++)
        b();//I want here to make parallel 

           //and wait here all threads are done


}

how can I use qhthread here,I ve looked to tutorials they all are just for classes not for a function?