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Ground granulated blast-furnace slags (GGBS) show improved hydration reactivity when granularity fineness increases, but the reason for the improvement in reactivity is still unknown. GGBS specimens with Blaine surface areas of 4680, 6470, and 8050 are analyzed, but the conventional reactivity criteria, such as degree of vitrification, basicity, and mineralogical composition, of the GGBS show no significant differences. X-ray photoelectron spectroscopic analysis, however, successfully distinguishes and identifies SiO 2 gels as well as glassy phases of CaO-SiO 2 and Al 2 O 3 -SiO 2 in the slag surfaces, where, with an increase in the Blaine surface area of the slag, CaO-SiO 2 -type glass becomes dominant and contributes to the evolution of hydration, determined in terms of silicate anion morphology by the trimethylsilylation (TMS) method.

The accumulation of plastic litter in natural environments has become a serious global issue. Since 1972, mega to micro/nanosized drifting plastics have been determined to be highly a significant pollutant in all oceans worldwide. To clarifying numerous problems such as entanglement or improper ingestion due to drifting and debris plastic, the amounts of currently drifting plastics should be determined. For this purpose, chemicals derived from polystyrene (PS) degradation were analyzed for 4000 sand and water samples taken from around the world including open sea sites (surface to 5000 m depth) during the period from 2000 to 2018. All styrene oligomers (SOs) of styrene (styrene monomer, SM), 2,4-diphenyl-1-butene (styrene dimer, SD2), and 2,4,6-triphenyl-1-hexene (styrene trimer, ST) were found to contain products from PS degradation. On the basis of survey SO values, 1.4 × 109 metric tons (MT) of SO were found to have been released into world oceans between 1950 and 2018. This SO subsequently underwent conversion to 2.7 × 106 MT of PS. Twenty percent underwent degradation, while 1.2 × 107 MT of PS apparently continued to drift about in ocean water. Drifting PS has been clearly shown not only to be crushed into micro/nanoplastic particles but also to degrade into basic structural units of SOs constituting PS.

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Since 1970, lumps of plastic breakage into micro/nano pieces has been clearly shown a serious and large source of ocean pollution. To clarify in detail the course of this impact, thermoplastics were decomposed at natural conditions kinetically. And field surveys conducted on four thousand sand and water samples including these at deep-sea sites from around the world during the period, 2000 to 2015. All samples were found to contain styrene oligomers (SOs), that had been generated from drifting polystyrene (PS) degradation. Lumps of plastic not only break up into micro/nano-fragments but also degrade into their basic structure units of plastic. From 1950 to 2015, 4.2 billion metric tons (MT) of SOs were shown to be generated from drifting PS. The monomers are newly and highly significant source of pollution of marine ecosystem directly and global warming of planet and should be given the utmost serious attention.