Bridged Ferrocenes VIII. Correlation of redox potentials with structure

The redox potentials for oxidation of ferrocenes with hydrocarbon bridges and of corresponding ketoferrocenes were measured. For the reduced compound correlations were observed between the potentials and the iron to ring distances. For the ketoferrocenes, the importance of proper alignment of the carbonyl with the cyclopentadienyl rings is noted. Other possible relationships are discussed.     

Bridged ferrocenes : VII. Synthesis of di- and tri-bridged ferrocenes with pentamethylne chains

Double or successive bridge-enlargement reactions were used on appropriate α-ketones followed by reduction to prepare 1,1′-pentamethyleneferrocene, VIII, 1,1′,3,3′-bis(pentamethylene)ferrocene, XX, and 1,1′,2,2t?,4,4′-tris(penta-methylene)ferrocane, XXX. The bridge-enlarging reactions are discussed, and the PMR spectral behavior of the polybridged ferrocenes is briefly discussed.     

Organic solvent extraction of uranium from alkaline nuclear waste

There are proliferation issues with the Plutonium Uranium Redox Extraction process due to the possibility of recovering plutonium. The objective of this research was to evaluate different organic extraction ligands that can remove uranium from the nuclear waste and to determine the most effective organic solvent for extracting uranium only, from alkaline media. The results indicate that Alamine 336 in xylene has zero (0%) extraction capability for surrogate fission products at an optimum extraction time of 15 min. Aliquat 336 in xylene has an extraction percentage of 72% for uranium in 60 min. However, Aliquat 336 in toluene extracted 82% of the uranium from the feed solution after 30 min, decreasing to 76% after 60 min.

     

On a formal analogue of the Bernoulli numbers

Using properties of the modular forms G_k, it is shown that G_K(z) = α_kω^2k where z is an integer in an imaginary quadratic field and α_k is algebraic and involves analogues of the Bernoulli numbers. A recursion formula (3) is given for these numbers.     

Enhanced Oxidation of Uric Acid at Thiourea-Modified Gold Electrode in Alkaline Media

Russian Journal of Electrochemistry - The surface of polycrystalline gold (Au (poly)) electrode was ex situ modified with self-assembled monolayer (SAM) of thiourea (TU) with a view of applying the...     

s- and t-Channel transformation matrices for helicity and invariant amplitudes for γ + N → 1 + N

The Algebraic transformation matrices, valid for all s and t, connecting the s- and t-channel helicity amplitudes to a corresponding set of gauge invariant covariant amplitudes are presented for the photoproduction processes γ + N → 1^± + N.     

Structural consequences of oxidation of ferrocene derivatives : II. 1,1′,2,2′,4,4′-tris(trimethylene)ferrocenium perchlorate

The crystal and molecular structures of 1,1′,2,2′,4,4′-tris(trimethylene)ferrocenium perchlorate (I) were determined by X-ray crystallography. Despite the rigidity imparted to the molecule by the three non-adjacent bridges, the iron-to-ring distance of the cation was 4.4(4) pm longer than in the neutral compound, in agreement with what was reported for non-bridged ferrocene derivatives. The increased separation of the rings was accommodated by an increase in angle between the -carbon atoms and the ring-planes and by an increase in the ring-ring tilt angle.     

Gas chemical adsorption characterization of lanthanide hexafluoroacetylacetonates

Newly-established adsorption enthalpy and entropy values of 12 lanthanide hexafluoroacetylacetonates, denoted Ln[hfac]₄, along with the experimental and theoretical methodology used to obtain these values, are presented for the first time. The results of this work can be used in conjunction with theoretical modeling techniques to optimize a large-scale gas-phase separation experiment using isothermal chromatography. The results to date indicate average adsorption enthalpy and entropy values of the 12 Ln[hfac]₄ complexes ranging from ?33 to ?139 kJ/mol K and ?299 to ?557 J/mol, respectively.