Dimeric silver(I) and gold(I) tert-butyl-imino-2,2-dimethylpyrrolidinates were synthesized and characterized by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), single-crystal X-ray diffraction, and chemical vapor deposition (CVD) experiments. The motivation for this work arose from the excellent thermal stability of the previously reported analogous copper(I) compound and included the completion of a series of potential precursors for atomic layer deposition. These compounds are stable in air and soluble in aromatic or chlorinated solvents. In the solid state, TGA and DSC showed these compounds to be thermally stable up to 170 °C and to have good evaporation yields up to 240 °C. Gas phase decomposition temperatures were 140 °C for the silver compound and 300 °C for the gold compound, as determined by CVD experiments, where these compounds decomposed to produce metallic films. Reduction of the metal ions via dehydrogenation of the ligands is proposed as a thermolysis pathway.

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Tribological testing and analysis of metallurgical-grade cokes were conducted to elucidate the nature of the surface of each coke and the influence of the surface on coke abrasion resistance. The coefficient of friction (COF) was contrasted between cokes of different coal origins. The results indicate that the COF increases with (i) parent coal vitrinite content and (ii) decreasing rank of the parent coal. The amount of ultrafine (i.e., <10 μm at the longest dimension) material produced by coke during continuous rotational tribological testing increased as the rank of the parent coal increased. Above a parent coal mean maximum vitrinite reflectance of 1.37%, the COF began to decrease slightly beyond the first 40–60 s of testing, which can be attributed to the anisotropic, graphitic ultrafines acting as a surface modifier or lubricant. This has implications for the abrasion resistance of coke under blast furnace conditions, in which graphitic ultrafines acting a lubricant would likely reduce the degradation rate of the coke. For the pilot oven coke from the blend examined, the COF at all stages of the experiment was approximately linear with blend composition. The exploratory study described in this paper indicates that the wear characteristics of inertinite maceral derived constituents (IMDC) and reactive maceral derived constituents (RMDC) are different and that the wear behavior of the RMDC is rank dependent, while that of the IMDC is less sensitive to the rank of the initial coal.

A coke produced using a custom-built sole-heated oven and a coke prepared in a pilot-scale oven from a matched coal, were compared using a range of analytical techniques. The aim of this comparison was to assess to what extent the small-scale sole-heated oven can successfully replicate the production of pilot-scale oven cokes, and thus be used to rapidly prepare and screen a wide range of cokes for particular characteristics, e.g. abrasion resistance. The techniques applied included conventional methods and novel methods developed by our research team. These included microstructural and microtextural analyses of samples of each coke, and tribological, scratch test and fractographic analyses, each of which elucidates different strength attributes. These include microstructural weaknesses, abrasion resistance, and the strength of microtextural interfaces. The level of replication achieved indicates that the sole-heated oven, used in combination with an annealing step in a muffle furnace, can be beneficially used to model the pilot-scale oven.

Deposition of gold metal on a tilted fiber Bragg grating (TFBG) demonstrates the utility of this optical fiber as a sensor for the conditions at the fiber's surface, including the continuity of a deposited metal film. Two precursors for the deposition of metallic gold are contrasted: gold(I) N'N'-dimethyl N,N”-diisopropylguanidinate (1) and gold(I) tert-butyl-imino-2,2-dimethylpyrrolidinate (2). Characterization of the deposition by optical fiber spectroscopy highlights the difference in thermal stability and growth rate of these two compounds. Compound 1 has a tremendous growth rate (220 nm/min) but is very thermally unstable, while 2 is much more thermally stable, and shows a lower growth rate of 1 nm/min.