use master  
go  
declare @Database nvarchar(256),@Path nvarchar(2048)  
select @Database=N‘AdventureWorks‘,@Path=N‘D:/TDDOWNLOAD/‘  
declare @sql nvarchar(max)  
select @sql =N‘BACKUP DATABASE ‘+@Database+N‘  
    TO  DISK = ‘‘‘+@Path+@Database+N‘_Full_‘+REPLACE(REPLACE(REPLACE(convert(nvarchar(30),getdate(),126),‘-‘,‘_‘),‘:‘,‘_‘),‘.‘,‘_‘)+N‘.bak‘‘  
WITH   
    NOFORMAT,   
    INIT,    
    NAME = N‘‘Full Database Backup‘‘,  
    SKIP‘  
exec (@sql)  
go