Supergauges and goldstone spinors

An example of a local conserved spinor current density is given, such that the corresponding symmetry is spontaneously broken and Goldstone states with spin one half occur.     

Efficient enantioselective synthesis of functionalized tetrahydropyrans by Ru-catalyzed asymmetric ring-opening metathesis/cross-metathesis (AROM/CM)

An efficient method for enantioselective synthesis of highly functionalized pyrans (up to 98% ee) through Ru-catalyzed asymmetric ring-opening metathesis/cross-metathesis is described. Reactions are promoted by a recyclable chiral Ru-chloride or a new chiral Ru-iodide complex; the latter catalyst is less efficient but gives rise to significantly higher levels of enantioselectivity. Catalytic reactions can be performed in undistilled solvent and with a wide range of substrates, including those that contain secondary and tertiary alcohols. Representative regioselective functionalizations that highlight the utility of the catalytic method are also presented.     

Raman Spectroscopy of Iron in Aqueous Carbonate Solutions

Surface-enhanced Raman spectroscopy is used for in situ study of an iron surface in aqueous carbonate solutions both on open circuit and at constant potentials. Raman signals are assigned to FeCO₃ and adsorbed water. Formation of FeCO₃ corresponds to lowering of iron dissolution.     

Additive conservation laws in local relativistic quantum field theory

We consider generatorsQ of symmetry transformations acting additively on asymptotic particle states according to (1.1). [This equation can be derived forQ defined as integral over a conserved local current!]. For simplicity, we consider only the case that all asymptotic fields are scalar. Assuming that elastic scattering occurs at least in an open subset of the scattering manifold we show thatQ is at most alinear combination of generators of the Poincaré group and internal symmetries.     

Use of differential scanning calorimetry to analyse the quality of certain vitamin drugs

The use of DSC to evaluate the quality of drugs is demonstrated via some typical problems: purity determination of nicotinamide, granulation of calcium D-(+)-pantothenate, drying of menadione sodium bisulfite, stability ofα-hydroxyvitamin D on storage, and purification of calcium homo-pantothenate, pyridoxal-5′-phosphate and pyridoxal-hydrochloride.     

An improved actinide separation method for environmental samples

This paper presents a rapid method of separation of five actinide elements (Th, U, Np, Pu, and Am) for aqueous media samples. This separation method utilizes the unique chemistries of the actinides at low concentrations^1,2 and the properties of the EIChroM TRU-Resin^TM extraction resin. In order to cleanly recover the five actinides from aqueous samples or solubilized soil samples, the sample is passed through the column twice. The sample is first loaded in an HCl solution with hydrogen peroxide. This allows the Am and most matrix ions to pass through the column. Then the Th is eluted using dilute HCl followed by the Np and Pu which are eluted together with oxalic acid in dilute HCl solution. Finally, the U is eluted with ammonium oxalate solution. A calcium-oxalate coprecipitation is performed on the original load solution containing the Am ions and the dissolved precipitate is then reloaded onto the TRU-Resin^TM column in HNO₃ with ascorbic acid. The procedure requires approximately 1.5 working days for experienced technicians, greatly reduces waste, and generally results in actinide recoveries of 80–100%.