Inverse mechanical-swelling coupling of a highly deformed double-network gel.

Mechanical behaviors of a polymer gel are coupled with its swelling behavior. It has been known that typical hydrogels display extension-induced swelling and drying-induced stiffening, called normal mechanical-swelling coupling. In this study, we experimentally found that highly extended double-network (DN) hydrogels exhibit abnormal inverse mechanical-swelling coupling such as extension-induced deswelling and drying-induced softening.

Computerized Hammer Sounding Interpretation for Concrete Assessment with Online Machine Learning.

Developing efficient Artificial Intelligence (AI)-enabled systems to substitute the human role in non-destructive testing is an emerging topic of considerable interest. In this study, we propose a novel hammering response analysis system using online machine learning, which aims at achieving near-human performance in assessment of concrete structures. Current computerized hammer sounding systems commonly employ lab-scale data to validate the models.

Understanding of the formation of mesostructured alkylammonium-alkaline earth metal phosphates composed of ionic frameworks.

A lamellar material composed of alternating layers of magnesium phosphate sheets and n-hexadecylammonium (n-C16H33NH3+) ions was synthesized by the reaction between magnesium acetate tetrahydrate and phosphoric acid. The chemical formula of the composite material was determined to be (n-C16H33NH3+)Mg2+(HPO4(2-))(H2PO4-) by ICP, TG, and 31P MAS NMR measurements. The lamellar composite was obtained under basic conditions adjusted with tetramethylammonium (TMAOH) and tetraethylammonium hydroxides (TEAOH), while ammonium ions did not act as an alkali source useful for obtaining the composite material.