Aerial surfaces of plants are covered by a waxy cuticle protecting plants from excessive water loss and UV light. In the present study, composition and morphology of cuticular waxes of northern wild berry species bilberry (Vaccinium myrtillus L.), lingonberry (V. vitis-idaea L.), bog bilberry (V. uliginosum L.) and crowberry (Empetrum nigrum L.) were investigated. Scanning electron microscopy (SEM) revealed differences in epicuticular wax morphologies and gas chromatographymass spectrometry (GC-MS) analysis confirmed variation in chemical composition of cuticular waxes between the berry species. The dominant compounds in bilberry and lingonberry cuticular waxes were triterpenoids while fatty acids and alkanes were the dominant ones in bog bilberry and crowberry, respectively. Wax extracted by supercritical fluid extraction (SFE) from industrial press cakes of bilberry and lingonberry contained linoleic acid and γ-linolenic acid as the dominant compounds. Furthermore, in vitro sun protection factor (SPF) of berry waxes depicted good UV-B absorbing capacities.

Stellite-6 coatings were deposited onto AISI 304 stainless steel substrate by gas-fueled HVOF spraying, systematically varying the process parameter settings. By operating the HVOF torch with a fuel-rich mixture, dense coatings (<1% porosity) are produced, containing up to ≈3 vol.% oxide inclusions. A substantial amount of a Cr-rich f.c.c. phase is found, mainly produced by quenching of molten lamellae, and distinct from the equilibrium, Co-based f.c.c. solid solution retained in unmelted particles. These coatings exhibit pseudo-passive behavior and survive 5 cycles (100 h) of the Corrodkote test (ASTM B380-97) with no substrate corrosion. Coatings obtained from oxygen-rich mixtures, on the other hand, contain fewer oxide inclusions but also greater porosity, and do not protect the substrate against corrosion. The wear behavior of the coatings is less influenced by deposition conditions. In ball-on-disk dry sliding tests, all coatings exhibit wear rates of 2-3 × 10-5 mm 3 /(N•m), higher than those reported for bulk or clad Stellite, because of interlamellar delamination. Strain-induced, "martensitic" phase transformation from the f.c.c. structure to a h.c.p. one is observed over a 1-2 µm depth below the contact surface. Additional tribo-oxidation is onset when frictional heat dissipation has heated the wear debris enough to trigger its reaction with the environment. Correspondingly, a transition to a regime of higher friction occurs (from ≈0.6 to ≈0.8). At 400 °C, lamellar delamination is suppressed but wear rates rise to 5-8 × 10-5 mm 3 /(N•m) because of abrasive and adhesive wear. At 800 °C, a dense "glaze" tribofilm is formed by sintered debris particles, firmly bonded to a thermally grown oxide scale on the underlying metal surface. The "glaze" protects the coating, lowering the wear rate to ≈1×10-5 mm 3 /(N•m) and the friction coefficient to <0.45. Under high-stress particle abrasion conditions, wear rates of ≈1×10-3 mm 3 /(N•m) are found.

Solid state phase of V 7 O 16 with separate V 2 O 5 phase were fabricated by pulsed laser deposition. The crystal structure and symmetry of the deposited films were studied with X-ray diffraction and Raman spectroscopy, respectively. Rietveld analysis was performed to the X-ray diffraction measurement results. The surface potentials and morphologies of the films were studied with atomic force microscopy, and microstructure of the thin films was analyzed by transmission electron microscopy. Raman spectroscopy and Rietveld refinement results confirmed that the thin-film crystal structures varied between orthorombic V 2 O 5 phase and another phase, triclinic V 7 O 16 , previously found only in the walls of vanadium oxide nanotubes (VO x -NT), bound together with organic amine. We have earlier presented the first results of stable and pure metal-oxide solid-state phase of V 7 O 16 manufactured from ceramic V 2 O 5 target. Here we show more detailed study of these structures. The microstructure studies showed a variation on the porosity of the films according to crystal structures and also some fiber-like nanostructures were found in the films. The surface morphology depended strongly on the crystal structure and the surface potential studies showed ~ 50 meV difference in the work function values between the phases. Compounds were found to be extremely sensitive towards ammonia, NH 3 , down to ~ 40 ppb concentrations, and have shown to 2 have the stability and selectivity to control the Selective Catalytic Reduction process, where nitrogen oxides are reduced by ammonia in, e.g. diesel exhausts.

Copper is an interesting material for printed electronics inks because, for example, of its good conductivity and lower raw material price compared to silver. However, post-processing Cu inks is challenging because of non-conductive copper oxide. In this work, inkjet-printed Cu nanoparticle structures were sintered on a polyimide substrate with a continuous-wave 808-nm diode laser. Laser sintering was tested by varying the sintering parameters (optical power and scanning velocity), and the electrical resistance of the samples was measured. A minimum sheet resistance of approx.90 mΩ/□ was obtained. All tests were run in room conditions. Sintered structures were then analyzed from SEM images. Results showed that laser sintering produces good repeatability, that a scanning velocity increment positively affects the process window, and that multiple sintering cycles do not increase conductivity.

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