A neutral heteroditopic pyridine N-oxide axle containing [2]rotaxane, synthesised via sodium cation templation, displays cooperative recognition of alkali metal cation-halide anion ion-pairs in an unprecedented axle component separated ion-pair binding fashion.

Metal ions are both ubiquitous to and crucial in biology. In classical simulations, they are typically described as simple van der Waals spheres, making it difficult to provide reliable force field descriptions for them. An alternative is given by nonbonded dummy models, in which the central metal atom is surrounded by dummy particles that each carry a partial charge. While such dummy models al...

We report a self-recognition phenomenon based on an assembly process in a homogeneous dilute aqueous solution of two nano-scaled, spherical polyprotic metal oxide-based macroions (neutral species in crystals), also called Keplerates of the type [(linker)₃₀(pentagon)₁₂]≡[{M(H₂O)}₃₀{(Mo)Mo₅}₁₂] where M is Fe(III) or Cr(III). Upon deprotonation of the neutral species, the resulting macroions assem...

Reduction of Cu(II) cations immobilized as cross-linkers in polyacrylate network colloids produce relatively small (~3 nm) Cu metal particles which are further tuned to smaller size (~1.5 nm) by partially substituting Ca(+2) for Cu(+2) in the polymer network colloid.

(6 ) Swyt, C. R. Fiori, C. E. Microbeam Analysis-1986; San Francisco Press: San Francisco, CA, 1986; p 482. (7) Myklebust, R. L.; Marinenko, R. B.; Newbury, D. E.; Bright. D. S. Microbsem Analysis1985; Sen Francisco Press: San Francisco, CA, 1985; p 101. (6 ) Mayr, M.; Angeili, J. X-Ray Spectrom. 1985, 14, 89. (9) Ono, Y.; Nbken, C. H.; Tagata, S.; Seo, Y. Microbeam Anawsis1985; San Francisco P...

Although the activating effect of metal ions, such as Co++ and Mn*, on a variety of aminopeptidases has long been known (see Smith (2)), no requirements of the pancreatic proteinases for these ions have been demonstrated. It has been found, however, that calcium salts improve the yield of trypsin from trypsinogen (3) and that they increase the stability of trypsin at alkaline pH (4, 5). Earlier...

Macrocyclic ligands form highly selective and kinetically labile complexes with a wide range of cations, including alkali metal and alkaline earth cations. Formation rate constants are high and remarkably insensitive to ligand structure, but decrease systematically with increasing charge density of the cation this behaviour is qualitatively similar to that expected for the dissociative intercha...

Coal gasification (IGCC) and pulverised coal combustion (PCC) fly ashes (FAs), obtained from two power plants fed with the carboniferous bituminous coal from Puertollano (Spain), were characterized. Both FAs were used as raw materials for zeolite synthesis by direct conversion and by alkaline fusion, and SiO2 extraction at laboratory scale. The Puertollano FAs are characterised by a high SiO2 c...

A physical model of selective "ion binding" in the L-type calcium channel is constructed, and consequences of the model are compared with experimental data. This reduced model treats only ions and the carboxylate oxygens of the EEEE locus explicitly and restricts interactions to hard-core repulsion and ion-ion and ion-dielectric electrostatic forces. The structural atoms provide a flexible envi...

Ypi1 was discovered as an essential protein able to act as a regulatory subunit of the Saccharomyces cerevisiae type 1 protein phosphatase Glc7 and play a key role in mitosis. We show here that partial depletion of Ypi1 causes lithium sensitivity and that high levels of this protein confer a lithium-tolerant phenotype to yeast cells. Remarkably, this phenotype was independent of the role of Ypi...