The adsorption and desorption of N2O on main-group ion-exchanged ZSM-5 was studied using temperature-programmed desorption (TPD) and density functional theory (DFT) calculations. TPD experiments were carried out to determine the desorbed temperature Tmax corresponding to the maximum mass intensity of N2O desorption peak and adsorption capacity of N2O on metal-ion-exchanged ZSM-5s. The results i...

Flexible anionic metal-organic frameworks (MOFs) are transformed into neutral heterobimetallic systems via single-crystal-to-single-crystal processes invoked by cation insertion. These transformations are directed by cooperative bond breakage and formation, resulting in expansion or contraction of the 3D framework by up to 33% due to the flexible nature of the organic linker. These MOFs display...

Salts of 3,5-dinitro-1H-1,2,4-triazole, a building block for energetic materials, have been prepared and fully characterized. Most of the studied salts exhibit high thermal stability and very low shock and friction sensitivities. 3,5-Dinitro-1,2,4-triazolates with the nitrogen-rich ammonium, guanidinium, aminoguanidinium, and aminotetrazolium cations are energetic and have potential for energet...

The complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions Lit Nat, Kt RIC and Cs+ in methanol-chloroform mixture have been evaluated at 25 °C, using UVVis spectrophotometric techniques. The results showed that the hgands are capable to complex with all...

Anion and cation permeabilities in dark-adapted Balanus photoreceptors were determined by comparing changes in the membrane potential in response to replacement of the dominant anion (Cl-) or cation (Na+) by test anions or cations in the superfusing solution. The anion permeability sequence obtained was PI greater than PSO4 greater than PBr greater than PCl greater than Pisethionate greater tha...

The alkali metal cations Na(+) and K(+) have several important physiological roles, including modulating enzyme activity. Recent work has suggested that alkali metal cations may be coordinated by pi systems, such as the aromatic amino acid side chains. The ability of K(+) to interact with an aromatic ring has been assessed by preparing a family of synthetic receptors that incorporate the aromat...

The alkali metal ion affinity of guanine quadruplexes has been studied using dispersion-corrected density functional theory (DFT-D). We have done computational investigations in aqueous solution that mimics artificial supramolecular conditions where guanine bases assemble into stacked quartets as well as biological environments in which telomeric quadruplexes are formed. In both cases, an alkal...

Because of contradictions in the literature, we reinvestigated the kinetics of the Birch reduction, i.e. the hydrogenation of benzene and its derivatives in metal ammonia solutions (MAS; containing solvated electrons e and metal cations M) with alcohols to yield the corresponding cyclohexa-1,4-dien compounds (e.g. 2Li+ 2CH3OH+C6H6)2CH3OLi+C6H8). The kinetics of this reaction are obscured since ...

By the use as tracers of 42K, 86Rb and 32P it has been shown that in the metabolism of Bact. lactis aerogenes (а) the alkali-metal ion enters the cell during oxidation of the carbon substrate (glucose, succinic acid, acetic acid), whether or not a nitrogen source is provided, so that growth occurs; in either event the alkali-metal ion subsequently leaves the cell again; (б) if the pH is lowered...