$(function() {
    $(".ul_recommend li").hover(function() {
        var ss = $(this);
        ss.siblings("li").removeClass("xl_hover");
        ss.addClass("xl_hover");

        if (ss.children("a").children("img").attr("src") == "") {
            var s = ss.children("a").children("p").attr("iUrl");
            ss.children("a").children("img").attr("src", s);
        }
    }, function() {
    });
});