Polarization of protons from the C(d,p)C reaction

The polarization of protons from the ¹²C(d, p)¹³C reaction has been measured for deuteron bombarding energies between 3.9 and 5.8 MeV. Angular distributions of the polarization for protons leaving ¹³C in its ground state have been measured for laboratory angles between 10° and 135° at several energies in the vicinity of a resonance at 4 MeV in order to determine the effect of that resonance on the polarization. Additional measurements were made at 0.4 MeV intervals throughout the energy range. These measurements demonstrate that the compound-nuclear resonances observed in the cross section do not significantly alter the polarization angular distributions except at back angles. The shape of the observed polarization angular distributions at all energies is quite similar to previous results obtained for deuteron bombarding energies up to 15 MeV.     

Comparison of the separation of lactic acid and l-leucine by liquid emulsion membranes

A mass transfer model originally proposed for the permeation of zinc and l-phenylalanine was slightly modified and used for calculating the mass transfer resistances in lactic acid permeation (using the secondary amine Amberlite LA-2 as a carrier) and l-leucine permeation (using the quaternary ammoniumchloride Aliquat 336 as a carrier). The results show that under optimized conditions lactic acid permeation is controlled by the rate of reaction and that l-leucine permeation is controlled by the rate of reaction and the diffusion through the emulsion globule. The model results were compared with batch experiments separating lactic acid and l-leucine from real fermentation broths. The comparison shows that the separation rate is affected by co-transport of pH regulating agents and to a smaller extent by the co-transport of water.     

Determination of tin in poly(vinyl chloride) by atomic-absorption spectroscopy

A simple procedure is described for the determination of tin in PVC by atomic-absorption spectroscopy with an air-hydrogen flame, after wet digestion of the sample with sulphuric acid and hydrogen peroxide.     

The preparation of silica entrapped homogeneous hydrogenation catalysts by conventional and ionic liquid mediated sol-gel routes

[RhCl(PPh₃)₃] has been entrapped inside silica matrices by two methods: a conventional sol-gel synthesis in ethanol/water and a new route performed in an ionic liquid. The activity of these heterogenised catalysts has been tested for the hydrogenation of styrene. The catalyst prepared in an ionic liquid was found to be more active and have low Rh leaching.     

Toxicity testing of oil-contaminated drilling cuttings

The luminescent bacterium Photobacterium phosphoreum has been used to examine samples of oily drilling cuttings from the sea bottom in the vicinity of a North Sea oil production platform. Because the presence of any fine particulate matter results in a depression of the bioluminescence, the cuttings must first be extracted and the extract filtered before mixing with the bacterial suspension. A sea-water extract of a low toxicity drilling oil gave a small but significant depression of bioluminescence, but extracts with 1% v/v ethanol or DMSO gave a 50% greater depression. Samples of cuttings from different depths (representing different ages, up to 15 years) showed a different pattern, with similar effects from the aqueous and the mixed-solvent extracts. It is assumed that the toxic component therefore is not originating from the drilling mud oil, but from some additive which has a rather higher solubility in water than the hydrocarbons.     

Entrapping homogeneous catalysts by sol-gel methods: the bottom-up synthesis of catalysts that recycle and cascade

Homogeneous catalysts entrapped in silica matrices, including ionic liquid containing 'ionogels', exhibit high selectivity, unexpected activity and excellent recyclability.     

Mechanical properties of aluminium laminates produced by accumulative roll bonding

Laminates of high and commercial purity aluminium layers were processed by accumulative roll bonding performed up to ten cycles. The mechanical properties were measured by tensile testing. Both yield strength and ultimate tensile strength increase with higher number of cycles. The fracture strain is decreased through the first ARB cycle, but increases during further processing to reach a maximum after the sixth cycle. It is found that the development of the microstructure, especially in the high purity layers, strongly influences the mechanical properties.