New polypropylene/glass composites: Effect of glass fibers from cathode ray tubes on thermal and mechanical properties

This study investigated the feasibility of using fibers obtained by the recycling of end life cathode ray tubes glasses (EOL-CRT glass) as new filler for polypropylene material. The effects of these new fibers on the mechanical properties of plastic composites were studied. Fracture surfaces were investigated by scanning electron microscopy. Based on the findings of this work, it appears evident that these new fibers can be used instead of commercial glass fibers providing good mechanical and thermal properties. Moreover the matrix modification in the hybrid composite led to better mechanical performances.     

Fracture Behavior in Cu46.5Zr46.5Al7 and Cu46.5Zr41.5Al7Y5 Bulk Metallic Glasses

The interplay between chemical composition, plastic behavior, and fracture modes of Cu_46.5Zr_46.5Al₇ and Cu_46.5Zr_41.5Al₇Y₅ bulk metallic glasses (BMGs) was investigated by compression tests and fracture surfaces analyses. The aim was to explore the possibility of coupling physical, chemical, and hardness properties, with adequate macroscopic compressive plasticity. Cylindrical test samples, having a height-to-diameter ratio equal to 2, were machined and ground from as-cast bars and were tested in compression between lubricated plates, the displacement being measured by a clip-gage inserted between the plates. Y free BMG engineering stress-strain curves show a plastic behavior consisting of successive sudden stress drops and linear reloading segments. A detailed analysis of these features was performed to yield a correlation between the plastic deformation steps and the released elastic energy associated with each serration.     

A multislice approach to the spherical aberration theory in electron optics

Abstract

A multislice, wave-optical approach to the spherical aberration theory in electron optics is presented for the case of magnetic lenses. It is shown that, in order to remedy the inadequacy of a naive attempt carried out by taking the standard multislice equations and simply adding the fourth order terms in the transverse coordinates in the phase both of the transmission function and of the propagation kernel, it is necessary to approximate the Schrödinger equation by a wide-angle differential equation of the parabolic type and to solve it by means of a marching type algorithm. It turns out that the solution can be separated into two parts, describing, as in the multislice method, the interaction of the incoming spherically aberrated axial wavefunction with the field in a slice, and the propagation in a drift space. When the propagation is evaluated by means of the stationary phase method, a differential equation is obtained for the spherical aberration coefficient, whose solution is identical to that obtained by Glaser in his particle approach based on the eikonal.     

Hydrotreating data interpretation by chemometrics

Hydrotreating in the presence of dispersed catalysts has been considered a promising route to obtain valuable fuels from heavy hydrocarbon cuts. A laboratory-scale study on the effect of operating conditions on heavy feedstock hydrotreating performances is reported. In order to maximise the effectiveness of the research activity, chemometrics was exploited both for experimental design and data interpretation.     

A Bifunctional Copper Catalyst for the One Pot-One Step Esterification?+?Hydrogenation of Tall Oil Fatty Acids

An efficient copper catalyst for the one-pot one-step hydrogenation?+?esterification of unsaturated free fatty acids is described. The high selectivity in hydrogenation promoted by copper, combined with the high activity in esterification observed with solid mixed oxides allows one to directly obtain stabilized methyl esters.     

Technical note: Identification of Prototheca species from bovine milk samples by PCR-single strand conformation polymorphism

We report the development of a PCR-single strand conformation polymorphism (SSCP) method to identify Prototheca spp. responsible for bovine mastitis: P. zopfii and P. blaschkeae. The method was set up using reference strains belonging to P. zopfii genotype 1, P. zopfii genotype 2, and P. blaschkeae as target species and P. stagnora, and P. ulmea as negative controls. The assay was applied on 50 isolates of Prototheca spp. isolated from bovine mastitic milk or bulk-tank milk samples, and all isolates were identified as P. zopfii genotype 2. We conclude that the described PCR-SSCP approach is accurate, inexpensive, and highly suitable for the identification of P. zopfii genotype 2 on field isolates but also directly on milk, if preceded by a specific DNA extraction method.