The AIHs are formed in 300 seconds by mixing hydrogel particles with liquid amine (left) which increases the contact area between the CO2 and the amine (right).

A new class of CO2 sorbents, namely polyethylenimine hydrogel beads (PEI HBs), has been developed via a simple one-step crosslinking reaction of PEI using epichlorohydrin (EPC).

Karrikins (2H-furo[2,3-c]pyran-2-ones) are potent smoke-derived germination promoters for a diverse range of plant species but, to date, their mode of action remains unknown. This paper reports the structure-activity relationship of numerous karrikin analogues to increase understanding of the key structural features of the molecule that are required for biological activity. The results demonstrate that modification at the C5 position is preferred over modification at the C3, C4, or C7 positions for retaining the highest bioactivity.

This paper describes the synthesis, structural characterization, and solution behavior of some xylyllinked imidazolium and benzimidazolium cyclophanes decorated with alkyl or alkoxy groups. The addition of alkyl/alkoxy chains to the cyclophanes allows for studies in chlorinated solvents, whereas previous solution studies of azolium cyclophanes have generally required highly polar solvents. The azolium cyclophanes may exist in a syn/syn conformation (azolium rings mutually syn, arene rings mutually syn) or a syn/anti conformation (azolium rings mutually syn, arene rings mutually anti). The preferred conformation is significantly affected by (i) binding of bromide (ionpairing) to the protons on the imidazolium or benzimidazolium rings, which occurs in solutions of bromide salts of the cyclophanes in chlorinated solvents, and (ii) the addition of alkoxy groups to the benzimidazolium cyclophanes. These structural modifications have also led to cyclophanes that adopt conformations not previously identified for similar azolium cyclophane analogues. Detailed 1 H NMR studies for one cyclophane identified binding of bromide at two independent sites within the cyclophane.3

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An X-ray crystallographic analysis of tris-(2,2',6',2"-terpyridyleuropium( 111) perchlorate has confirmed the nona-co-ordination of the metal ion, believed to be the first example of nine-co-ordination involving only nitrogen ligands.

We report the rapid and scalable preparation of PEI snow that can remove CO2 from air under industrial conditions.

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