PMC

Cephalopods and their ink-producing glands. These 19th century images have been relabeled and retouched for clarity. (A,B) Squid and its ink sac. (A) Illex illecebrosus, from of Plate XXXIX of Verrill in 1880 []. (B) Doryteuthis pealeii, from Figure 13 of Williams in 1909 []. The ink sac is labeled by an asterisk; (C) Ink sac from the cuttlefish, Sepia officinalis, from Figure 291 of Lang and Hescheler in 1900 []. a, anus; 1, common sac of the rectum and ink sac; 2, rectum; 3, ampulla of the duct of the ink sac; 4, anterior sphincter muscle of the ink sac; 5, posterior sphincter muscle of the ink sac; 6, duct of the ink sac; 7, reservoir of the ink sac; 8, opening of the ink gland; 9, ink gland; 10, basal germinal zone; (D,E) Funnel organ of squid; (D) Ventral view of the funnel organ from Desmoteuthis tenera (=Teuthowenia megalops) from d of Plate LV from Verrill in 1880 [] and from Loligo; (E-1) Ventral view and (E-2) dorsal view, from of Laurie in 1888 []. The funnel organ, located on the funnel near the siphon (s) and siphonal valve (v), is composed of a median organ (m), two lateral cushions (n, n′) and a papilla to each (one medio-dorsal papilla, i, and two lateral papillae, i′).

(A) Electrical resistivity of GaIn₁₀-based liquid metal ink as a function of oxygen content contained in 40g GaIn₁₀-based liquid metal ink at room temperature. (B) Electrical resistivity of GaIn₁₀-based liquid metal ink as a function of measuring temperature.

The cyclic voltametric response obtained for 1.0 mmol L⁻¹ [Fe(CN)₆]^3−/4−varying reference electrode. (a) GCE vs. (red line) Ag|AgCl|KCl(sat.); (black) commercial ink; (pink) Ag-NP ink; (blue) Ag-SL ink; (green) AgCl|Ag-NP ink; and (orange) AgCl|Ag-SL ink. (b) GP-SL/AC vs. (red line) Ag|AgCl|KCl(sat.); (black) commercial ink; (pink) Ag-NP ink; (blue) Ag-SL ink; (green) AgCl|Ag-NP ink; (orange) AgCl|Ag-SL ink; and (purple) graphite ink. (c) 3D-printed CB/PLA vs. (red line) Ag|AgCl|KCl(sat.); (black) commercial ink; (pink) Ag-NP ink; (blue) Ag-SL ink; (purple) CB/PLA; using 0.1 mol L⁻¹ KCl as supporting electrolyte scan rate: 50 mV s⁻¹.

Ageing of inks prepared from different routes for printing oxide films. (a) Ink A1: 0.1 mol l⁻¹ SiO₂ in FAM solvent, with particle size of approximately 260 nm. (b) Ink A2: 0.1 mol l⁻¹ SiO₂ in FAM solvent, with particle size of approximately 520 nm. (c) Ink B: 0.25 mol l⁻¹ TiO₂ in IPE solvent. The particle size is in the range of 70–400 nm. (d) Ink C: 0.02 and 0.001 mol l⁻¹ Fe₃O₄ nanoparticle suspensions in DI water. (e) Ink D: 0.02 and 0.001 mol l⁻¹ Fe₃O₄ aqueous ferrofluids. (f) Ink E: 0.25 mol l⁻¹ [Zn] acetate in IPE solvent. (g) Ink F: 0.25 mol l⁻¹ acetates in IPE solvent with 10 at% [Fe] in [Zn] + [Fe]. (h) Ink G: 0.25 mol l⁻¹ acetates in IPE solvent with 5 at% [Mg] in [Zn] + [Mg]. (i) Ink H: 0.25 mol l⁻¹ Mg acetate in MOE solvent. (j) Ink I: 0.1 mol l⁻¹ acetates in MOE solvent with 2 at% [Fe] in [Mg] + [Fe]. (k) Ink J: 0.1 mol l⁻¹ acetates in ATA solvent with 10 at% [Sn] in [In] + [Sn]. (l) Ink K: thermal chelated ink for ink J, 0.1 mol l⁻¹ with 10 at% [Sn] in [In] + [Sn].