How to Export subsite and Import in another web application?

created a new Site Collection and put it into an open ContentDB.

PS script with: Add-PSSnapin Microsoft.SharePoint.PowerShell.

Backup-SPSite http://peakfinders/sites/portal –Path c:\sitebackup.bak -UseSqlSnapshot 

Restore-SPSite  http://peakfinders/sites/portal -Path c:\sitebackup.bak

Remove-SPSite  http://peakfinders/sites/portal –GradualDelete