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Organoindium compounds of redox active 1,2‐benzenedithiolate and 2‐amidobenzenethiolate ligands were synthesized and tested for reactivity against mild oxidants. The reaction of Me3In and (NCN)InMe2 [NCN=2,6‐bis(dimethylaminomethy)phenyl] with 3,4‐toluenedithiol (H2tdt) at room temperature afforded [MeIn(tdt)(py)]2 (1) and (NCN)In(tdt) (2), respectively. A similar reaction of Me3In with 2‐aminobenzenethiol (H2abt) in toluene under reflux afforded [MeIn(abt)(py)]2 (3). The reaction of (NCN)InCl2 with one equivalent of Li2(abt) or two equivalents of Li(Habt) afforded the compounds [(NCN)In(abt)]⋅LiCl(thf)2 (4⋅LiCl(thf)2) and (NCN)In(Habt)2 (5), respectively. The X‐ray crystal structures of 1 and 3 are similar and show dimeric structures via μ‐S‐(tdt) and μ‐N‐(abt) ligands, respectively. Compounds 2 and 4 possess similar monomeric structures and tridentate NCN pincer ligands. DFT computational studies have been used to rationalize the observed solid‐state structures and discern the potential reactivity of compounds 1–4 against oxidants. The reaction of 1 and 2 with excess iodine resulted in loss of the 3,4‐toluenedithiolate ligand and the formation of the oligomeric disulfide [tdt]n, while 3 and 4 showed no reactivity under similar conditions. This contrasts the reactivity of previously reported organoindium o‐amidophenolate complexes which undergo oxidative addition of iodine to afford ligand‐centered radical species. [ABSTRACT FROM AUTHOR]

The objective of this research is to develop a microelectromechanical system (MEMS)-based intelligent hybrid Biaxial Strain Transducer (BiAST) sensor for predicting railroad fatigue life based on strain history. The developed BiAST prototype was deployed to collect real-time strain data from the full-scale test track at the Transportation Technology Center (TTCI), near Pueblo, Colorado. The collected strain data were analyzed using the 'Binner' fatigue analysis program for counting the load cycles and estimating the fatigue life of a rail structure. Field-testing results of the BiAST were used to evaluate the BiAST prototype with respect to its repeatability, accuracy, and hybridization. BiAST was effective in detecting the dynamic response of a particular wheel and spurious overload events. BiAST can be used to detect passing wheels, train speed, and track condition. CE Database subject headings: Transducers; Evaluation; Fatigue life.