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In this work, a highly selective and efficient polymer adsorbent inspired by a water-soluble sulfonated poly(arylene ether nitrile) (SPEN) was successfully synthesized. Due to the distinct structure of functional carboxyl, sulfonic acid and rigid benzene rings, a facile aluminium (III) ions crosslinking method was employed to fabricate the SPEN-based adsorbents (SPEN-Al). Among the three adsorbents, SPEN-Al-2 exhibited superior adsorption capacities with uniform morphology. Subsequently, the SPEN-Al-2 was selected as the adsorbent for three cationic dyes (rhodamine B (Rh B), neutral red (NR), methylene blue (MB)) and three anionic dyes (orange G (OG), methyl orange (MO), acid fuchsin (AF)), respectively, demonstrating that the adsorbent possessing excellent selectivity toward cationic dyes. Moreover, the dye&rsquo, s adsorption selectivity of SPEN-Al-2 was further certificated in a binary cationic-anionic dyes mixtures (MB/OG and MB/MO) system. Taking MB as a dye model, a series of factors (contact time, concentration, temperature and pH) and adsorption models were systematically investigated in dye adsorption experiments. Results indicated that the adsorption was endothermic and the maximum adsorption capacity of SPEN-Al-2 could reach up to 877.5 mg/g, pseudo-second-model and Langmuir model were fitted to the adsorption kinetics and equilibrium isotherm, respectively, manifesting that SPEN-Al adsorbent was promising in the dyes removing field.

Photoelectron spectra of Al - n and Ga - n clusters in the size range n=1–15 are presented. Using 5.0 and 3.68 eV UV light (KrF excimer and nitrogen laser, respectively), electrons from molecular orbitals corresponding to the 3p and 4p orbitals of the atoms are detached. The spectra reveal a rich fine structure not observed in earlier experiments. The data are compared with the results of quantum chemical calculations. A change in the pattern of the spectra near n=6 can be interpreted as a transition from planar to compact 3D structures. The spectrum of Al - 13 agrees with the icosahedral structure predicted for this particle. The data do not agree with jellium model predictions. Differences between Al and Ga data can be correlated with the larger binding energy of the Ga 4s band.