[XeTeX] encoding radicals in traditional Chinese

[Daniel Greenhoe]

I am having trouble encoding some of the radicals in traditional Chinese using XeLaTeX. I have read that the radicals exist in the Unicode U+2F00-2FDF and in the CJK Radicals Supplement range 2E80-2EFF:
  http://en.wikipedia.org/wiki/List_of_Kangxi_radicals

Can someone tell me how to encode these characters into a XeLaTeX document (using UTF-8 encoding)?

Is there a command like \utf8{x2F39} to encode the character at U+2F39 in the Unicode code table?

Many Thanks in advance,
Dan