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To ensure the safety of infrastructure users, the long-term skid resistance is a crucial factor and is determined in large by the mineralogical and morphological characteristics of surfacing aggregate. Most studies have investigated these aggregate properties separately without considering the interrelation between one another. The objective of this study is to consider the morphological characteristics as well as the mineralogical fingerprint of aggregate to develop an innovative approach to optimize the aggregate selection process. The investigations are based on 11 different aggregate types with a broad range of mineralogy, commonly used in Germany. The long-term influence of polishing and wearing on the surface aggregate was simulated by means of the Aachen Polishing Machine and the Micro-Deval test respectively. To evaluate the impact of these tests, the aggregate shape was characterized by means of an imaging system called Aggregate Image Measurement System while the skid resistance of aggregates was evaluated with the British Pendulum Test. The test results show that the quartz and calcite are the key crystals to determine the anti-wear resistance of aggregates. A correlation between the skid resistance, morphological properties and mineralogy is derived, which proves the mineralogical fingerprint technology is practical for characterization of aggregates used in pavement surface layers.

Metal–organic frameworks (MOFs) and covalent–organic frameworks (COFs), which feature porous crystalline materials, have attracted significant attention in the field of electrochemical energy storage owing to their adjustable pore structure, diverse topology, high specific surface area, well-defined periodic structures, and numerous redox active sites. Rechargeable aqueous zinc-ion batteries (ZIBs) are considered the most promising electrochemical energy storage devices because of their low cost, large capacity, and inherent safety features. This review article provides an overview of the recent advances in the development and fabrication of MOFs and COFs as anodes, cathodes, electrolytes, and separators for ZIBs in the last three years. Furthermore, the key principles for the controlled preparation of various MOFs and COFs, as well as the mechanisms for enhancing electrochemical performance are presented in depth by their applications in ZIBs. Finally, the major challenges and prospects of utilizing MOFs and COFs for ZIBs applications are outlined.

Polyester having amino sulfonic acid moieties (TBES) was prepared by a liquid/solid biphase polycondensation of terephthaloyl chloride (TPC) and N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES) in trimethyl phosphate (TMP) using triethylamine (TEA) as an acid acceptor. Blends of TBES with PVA and their metal complexes with Ni²⁺ and Co²⁺ ions were prepared. A strong interaction was observed between TBES and PVA. An electric conductivity of 10⁻⁶ S cm⁻¹ was attained for the blend films containing about 5 wt % water. A coordination structure with two chelate rings is proposed for the metal complex with Ni²⁺ and Co²⁺ ions when the molar ratio of amino sulfonic acid groups in TBES to metal ions is larger than 2. Polymer blends complexed with Ni²⁺ or Co²⁺ ions result in semi-interpenetrating polymer networks from chelate formation. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3561–3569, 1997