We report an experimental realization of a gel system in which frustrations exist and can be minimized, thus meeting two crucial criteria predicted to enable memory of conformations in polymers. The gels consist of a thermosensitive major monomer component and two minor components. One minor component is positively charged and will form complexes around negatively charged target molecules placed in solution. The complexes can be imprinted into the gel by then cross-linking the second minor component, which will form cross-links additional to those in the major polymer matrix. The complexes are destroyed and reformed upon swelling and reshrinking of the gels, showing that memorization has been achieved.

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A tripolar vortex, three aligned vortices with alternate signs of polarity of rotation, has been observed in a plasma for the first time. The tripolar vortex always appears with a deep density depression in the neutral particles, and the rotation direction of each vortex is opposite to that of the E×B rotation due to the ambipolar electric field. It is shown that a net momentum transfer during the charge-exchange interaction produces an effective force acting on the ions. The present experiment shows that this effective force may dominate the ambipolar-electric field and drive the anti-E×B vortical motion of ions.

In the present study, in order to examine the N,N-dimethylaminopropylacrylamide/acrylamide {DMAPAA/AAm} hydrogels' capabilities of repetitive heavy-metal-anion recovery from waste fluid, the authors performed successive Cr(VI) adsorption and the adsorbed-Cr(VI) desorption experiments. It has been proved that the DMAPAA/AAm gels show both of the high Cr(VI)-capturing functionality and Cr(VI)-desorption efficiencies. The results in the present study have demonstrated a possibility of a heavy-metal-anion recycling system in which the hydrogels are reused a number of times.