请给我一些中国sntp服务器列表答:biofiz.mf.uni-lj.si=Slovenia, University of Ljubljana info.cyf-kr.edu.pl=Poland, Academic Computer Centre, Krakow bitsy.mit.edu=USA, MA, Cambridge, MIT Information Systems nic.near.net=USA, MA, Cambridge time-b.nist.gov= ntp-1.ece.cmu.edu=USA, PA, Pittsburgh, Carnegie ...