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Reflectance images of: (a) HF-treated barcode NW; and (b) NaOH-treated barcode NW. Two-dimensional LCM PL images of: (c) HF-treated barcode NW; and (d) NaOH-treated barcode NW. LCM PL spectra of: (e) HF-treated barcode NW; and (f) NaOH-treated barcode NW.
