Perhaps you should try some spelling variations:
"biochemical characterization" » "chemical characterization", "mechanical characterization", "material characterization"
"physical characterization" » "chemical characterization", "mechanical characterization", "material characterization"
"optical characterization" » "chemical characterization", "material characterization", "functional characterization"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("physical characterization") OR ("physical characteristics"))) OR ((("optical characterization") OR ("biochemical characterization")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"physical characterization\") OR (\"physical characteristics\"))) or (((\"optical characterization\") or (\"biochemical characterization\"))))".
• Removing quotes may allow a broader search: (((( physical characterization ) OR ( physical characteristics ))) or ((( optical characterization ) or ( biochemical characterization )))).
• Adding a wildcard symbol may retrieve word variants: (((("physical characterization") OR ("physical characteristics"))) or ((("optical characterization") or ("biochemical characterization"))))*.