exp  'system/"system@dbsec"'  buffer=8192  wner=channel,wm_wms  file=ccpt.dmp consistent=n compress=n log=ccptexp.log 

imp  'system/"system@dbsec"'  fromuser=channel,wm_wms  touser=channel,wm_wms  file=ccpt.dmp  log=ccptimp.log ignore=y   

$ exp 'u_test/"dba/123,@lk.com"@db_wending' file=u_test.dmp buffer=4096000