$result = new NamedGraphMem("resultGraph");

$statement1 = new Statement(new Resource("http://example.org/bill"),new Resource("http://example.org/ns#knows"),new Blanknode("bNode1"));
$statement2 = new Statement(new Resource("http://example.org/joe"),new Resource("http://example.org/ns#knows"),new Blanknode("bNode1"));



$result->add($statement1);
$result->add($statement2);