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Abstract: Novel magnetic organo-bentonite-Fe3O4 poly(sodium acrylate) (OB-Fe3O4 PSA) superabsorbent nanocomposites were synthesized in aqueous solution through the copolymerization of partially neutralized acrylic acid (SA) on OB-Fe3O4 nanoparticle by using N,N′-methylenebisacrylamide as crosslinker and ammonium persulfate as initiator. This new superabsorbent was characterized by FTIR, TGA, FE-SEM and XRD. Its iron content and magnetic properties were studied by using inductively coupled plasma (ICP) and a vibrating sample magnetometer (VSM), respectively. The water retention test of OB-Fe3O4 PSA was also performed. The introduced OB-Fe3O4 could form a loose and coarse surface and improve the water absorbency of OB-Fe3O4 PSA superabsorbent. The effects of pH, ionic strength, and humic substances (HS) on the adsorption of Th(IV) were investigated in detail through batch experiments. The maximum adsorption capacity (Qmax ) of Th(IV) on OB-Fe3O4 PSA 3.6 superabsorbent at pH 3.0±0.05 and T=298K was about 6.55mmol/g, higher than any value previously reported. The thermodynamic parameters calculated from temperature-dependent adsorption isotherms suggested that Th(IV) adsorption on OB-Fe3O4 PSA superabsorbent was an endothermic and spontaneous process. Furthermore, OB-Fe3O4 PSA superabsorbent could be regenerated through the desorption of Th(IV) using 0.1mol/L HCl solution and the adsorption capacity was still higher than 3.6mmol/g after five consecutive adsorption–desorption processes. [Copyright &y& Elsevier]

[Display omitted] • An equivalent algorithm and a testing equipment are proposed to achieve synchronous corrosion and fatigue testing. • We observe for the first time that a deceleration-to-acceleration tendency for corrosion-fatigue testing for the Ti6Al4V ELI specimens. • The mechanism for the inconspicuous phenomenon is attributed to the competition between the corrosion-induced crack tip blunting and the material volume degradation. The Ti6Al4V ELI titanium alloy is a promising structural material for deep-sea equipment due to the advanced mechanical properties. The damage evolution of the Ti6Al4V ELI induced by cyclic loading accompanying with marine corrosion should be quantified to achieve structural integrity design for deep-sea equipment. However, synchronous acceleration testing for fatigue and corrosion is still challenging, due to the lack of equivalent acceleration ratio between fatigue and corrosion. Here we propose a calculation algorithm to determine the corrosion acceleration ratio based on the electric charge transmission during the corrosion process. Accordingly, we design a testing equipment with controllable current through corrosive solution. The corrosive acceleration ratio is modified by controlling current intensity. Then we observe for the first time that a deceleration-to-acceleration tendency for corrosion-fatigue testing for the Ti6Al4V ELI specimens. In addition, we reveal that this inconspicuous phenomenon is attributed to the competition between the corrosion-induced crack tip blunting and the material volume degradation. These findings provide insights for assessing the Ti6Al4V ELI, thereby designing for the deep-sea equipment. [ABSTRACT FROM AUTHOR]