Production of aggregate from non-metallic automotive shredder residues

In this paper, the results of an experimentation on the production of granules suitable to be used as aggregates in cementitious or asphalt mixes are presented and discussed. The granules were obtained by granulating the non-metallic fraction of automotive shredder residues. In a preliminary separation step the fluff fraction containing mainly inert and non-metallic materials was sieved and analyzed for the metal content. In the following granulation step, the sieved fraction was mixed with binding materials, fly ash and a densifier agent, to produce granules of 5-30 mm of diameter and up to 1400 kg/m3 of specific weight. The granulation was carried out at room temperature in a rotating tank. Concrete samples prepared using as aggregates the produced granules showed a specific weight up to 1800 kg/m3 and a compressive strength up to about 55% of reference samples prepared using a calcareous aggregate, depending on the fluff content of the mixes, and on the nature of the binder and of the other components used.     

Predicting embrittlement of polymer glasses using a hydrostatic stress criterion

In this study, the aging-induced embrittlement of three polymer glasses is investigated using a previously developed hybrid experimental–numerical method. The evolution of yield stress of unnotched tensile bars upon aging is coupled to the evolution of embrittlement of notched tensile bars using a numerical model combined with a critical hydrostatic stress criterion that determines the onset of failure. The time-to-embrittlement of notched tensile bars with a different notch geometry is predicted and in good agreement with the experimentally determined value. Next to that, the approach is extended to three polysulfone polymers, and it is shown that the value of the critical hydrostatic stress correlates well with the polymers entanglement density: : polymers with a denser entangled network display higher values, that is, a higher resistance against incipient cavitation. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47373.     

Real-time PCR based procedures for detection and quantification of Aspergillus carbonarius in wine grapes

Aspergillus carbonarius is the main species responsible for ochratoxin A accumulation in wine grapes and consequently, its rapid and sensitive detection is increasingly investigated. A new real-time PCR (RTi-PCR) based procedure was developed for the rapid and specific detection and quantification of A. carbonarius in wine grapes. The procedure includes the use of the pulsifier equipment to remove conidia from grapes which prevents releasing of PCR inhibitors, and DNA extraction with the EZNA Fungal DNA kit. It reduced the time for A. carbonarius DNA extraction from grapes to 30 min. Two specific primers (AcKS10L/AcKS10R) delimiting a 161 bp fragment, and a probe were designed and directed to the beta-ketosynthase domain of a polyketide synthase from A. carbonarius. Specificity was confirmed by testing primers towards purified DNA from 52 fungal strains, including reference and food isolates. Quantification was linear over at least 5 log units using both serial dilutions of purified DNA and calibrated conidial suspensions from A. carbonarius. The SYBR-Green I and TaqMan RTi-PCR approaches established were able to detect at least 2.4 and 24 genomic equivalents, respectively, using purified DNA. Results obtained from conidial suspensions, after DNA extraction, showed that at least 5 conidia per reaction should be present for a positive result with SYBR-Green I and 50 in the case of TaqMan. The quantification of fungal genomic DNA in artificially inoculated wine grapes performed successfully, with a minimum threshold of 10(3) conidia mL(-1) for accurate quantification. The developed RTi-PCR assay is a promising tool in the prediction of potential ochratoxigenic risk, even in the case of low-level infections, and suitable for a rapid, automated and high throughput analysis.     

High performance size-exclusion chromatography analysis of polar compounds applied to refined, mild deodorized, extra virgin olive oils and their blends: An approach to their differentiation

An investigation was carried out to evaluate the use of High Performance Size-Exclusion Chromatography (HPSEC) of polar compounds of refined, mild deodorized, extra virgin olive oils as well as of their blends, in attempting to reveal significant differences in the amounts of the substance classes constituting polar compounds among these oils. Two sets of blends were prepared by mixing an extra virgin olive oil with both refined and mild deodorized olive oils in increasing amounts. The obtained data highlighted that the triacylglycerol oligopolymers were absent or present in traces in the extra virgin olive oil, while their mean amount was equal to 0.04 g/100 g and 0.72 g/100 g in mild deodorized and refined olive oils, respectively. Oxidized triacylglycerols and diacylglycerols were more abundant in mild deodorized oil and refined oil than in extra virgin olive oil. The Factorial Discriminant Analysis of the data showed that the HPSEC analysis could reveal the presence of refined/mild deodorized oils in extra virgin olive oils. In particular, the classification functions obtained allowed designation of mixtures containing at least 30 g/100 g of mild deodorized oil and all those containing refined olive oil as deodorized oil, therefore as oils subjected to at least a mild refining treatment.     

Thin‐film nanostructure and polymer architecture in semicrystalline syndiotactic poly(p‐methylstyrene)–(cis‐1,4‐polybutadiene) multiblock copolymers

The thin‐film morphology of stereoregular syndiotactic poly(p‐methylstyrene)–(cis‐1,4‐polybutadiene) (sP(pMS–B)) multiblock copolymers has been investigated using tapping mode atomic force microscopy with variation of the polymer composition and monomer block lengths. The morphology of the thin films ranges from isolated circular domains of sP(pMS) embedded into a matrix of polybutadiene (PB) to isolated domains of PB embedded into a matrix of sP(pMS), passing through bicontinuous (jagged) lamellae when the pMS concentration is in the range 20–67 mol%. Multiple folding of the polymer segments, i.e. where reciprocal inclusions of polymer segments to each other phase are able to generate greater domain, has been postulated and validated by considerations on the polymer architecture and the thermal and crystalline behaviour. © 2019 Society of Chemical Industry