That is confusing! It is saying DST, and 东部标准时间 sounds like EST.
But EDT is UTC-4!
Beijing is UTC+8
So, if it is UTC-4, it is Monday, 7 September 2015 at 2:30-3:00 (am)
If it is really UTC-5, it is Monday, 7 September 2015 at 3:30-4:00
UTC is 'universal time' - it is the time in Britain (but without any daylight time).
DST is daylight saving time - that is the 'standard' time for that region, but one hour ahead. It only applies in summer. Here in New Zealand NZST is standard time and is UTC+12. NZDT is daylight savings time, and is UTC+13, but only during summer. Then there is the complication of _when_ summer is, and when DST applies