Nitinol (nickel-titanium or Ni-Ti) is the most utilized shape memory alloy due to its good superelasticity, shape memory effect, low stiffness, damping, biocompatibility, and corrosion resistance. Various material characteristics, such as sensitivity to composition and production thermal gradients, make conventional methods ineffective for the manufacture of high quality complex Nitinol components. These issues can be resolved by modern additive manufacturing (AM) methods which can produce net or near-net shape parts with highly precise and complex Nitinol structures. Compared to Laser Engineered Net Shape (LENS), Selective Laser Melting (SLM) has the benefit of more easily creating a high quality local inert atmosphere which protects chemically-reactive Nitinol powders to a higher degree. In this paper, the most recent publications related to the SLM processing of Nitinol are reviewed to identify the various influential factors involved and process-related issues. It is reported how powder quality and material composition have a significant effect on the produced microstructures and phase transformations. The effect of heat treatments after SLM fabrication on the functional and mechanical properties are noted. Optimization of several operating parameters were found to be critical in fabricating Nitinol parts of high density. The importance of processing parameters and related thermal cooling gradient which are crucial for obtaining the correct phase structure for shape memory capabilities are also presented. The paper concludes by presenting the significant findings and areas of prospective future research in relation to the SLM processing of Nitinol.

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The synthesis and characterisation of two terpyridine based ruthenium/palladium heteronuclear compounds are presented. The photocatalytic behaviour of the Ru/Pd complex containing the linear 2,2′:5′,2′′-terpyridine bridge (1a) and its analogue the non-linear 2,2′:6′,2′′-terpyridine bridge (2a) are compared together with the respective mononuclear complexes 1 and 2. Irradiation of 1a with visible light (e.g., 470 nm) results in the photocatalytic generation of dihydrogen gas. Photocatalysis was not observed with complex 2a by contrast. A comparison with the photocatalytic behaviour of the precursors 1 and 2 indicates, that while for 1a the photocatalysis is an intramolecular process, for the mononuclear precursors it is intermolecular. The photophysical and electrochemical properties of the mono-and heterobinuclear compounds are compared. Raman spectroscopy and DFT calculations indicate that there are substantial differences in the nature of the lowest energy 3 MLCT states of 1a and 2a, from which the contrasting photocatalytic activities of the complexes can be understood.

The palladium-catalysed cross-coupling reaction between 3,8-dibromo-1,10-phenanthroline with phenylacetylene or 3,5-bis(trifluoromethyl)phenylboronic acid gives good yields of the 3,8-disubstituted products. These 1,10-phenanthroline derivatives are used for the formation of novel ruthenium complexes of the type [(tbbpy) 2 Ru(phenR 2 )] 2+ [where tbbpy = 4,4Ј-di-tert-butyl-2,2Ј-bipyridine, phen = 1,10-phenanthroline, R represents the substituents at the 3,8 positions with bromine, phenylacetylene or 3,5-bis(trifluoromethyl)-phenyl]. All compounds are completely characterised by NMR and UV/Vis spectroscopy, MS, electrochemical measurements and Raman and resonance Raman spectroscopy.

A pyrazine bridged ruthenium/palladium bimetallic photocatalyst with peripheral 4,4'-dicarboxyethyl-2,2'-bipyridine ligands, EtOOC-RuPd, is reported, together with its 2,2'-bipyridine analogue. Upon irradiation with visible light, EtOOC-RuPd catalyses the production of hydrogen gas whereas the complex RuPd does not.

This paper presents a method for fabrication of microchannels on cyclic olefin polymer films that have application in the field of microfluidics and chemical sensing. Continuous microchannels were fabricated on 188-µm-thick cyclic olefin polymer substrates using a picosecond pulsed 1064 nm Nd:YAG laser. The effect of laser fluence on the microchannel morphology and dimensions was analysed via scanning electron microscopy and optical profilometry. Single laser passes were found to produce v-shaped microchannels with depths ranging from 12 to 48 µm and widths from 44 to 154 2 µm. The ablation rate during processing was lower than predicted theoretically. Multiple laser passes were applied to examine the ability for finer control over microchannel morphology with channel depths ranging from 22 µm to 77 µm and channel widths from 59 µm to 155 µm. For up to five repeat passes, acceptable reproducibility was found in the produced microchannel morphology. Infrared spectroscopy revealed that the polymer surface chemistry was not significantly altered via the laser ablation process. These results were compared to other work conducted on cyclic olefin polymers.

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Novel cyclometallated iridium-Pt/Pd dinuclear complexes containing the bridging ligand 2,2':5',2''-terpyridine (BPP) and the peripheral phenylpyridine (ppy) ligand produced hydrogen under both visible (470 nm) and UV (350 nm) irradiation. The turnover numbers using visible light were found to be significantly higher, indicating an interplay between two independent excited states, only one of which produces H(2) efficiently.