require 'time'
d = 
t = Time.parse(d)
puts t.rfc2822
puts t.zone

new = t + 12*3600
puts new.rfc2822
puts new.zone


require 'rubygems'
require 'active_support'
zone = ActiveSupport::TimeZone['Beijing']
remote = zone.at(new)

puts remote.rfc2822
puts remote.zone