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Natural fibre-based materials are becoming a valid alternative to traditional synthetic based products for composite reinforcing and sound attenuating treatments. In recent years, natural fibres have been used more frequently in the development of structural components and sound absorbing panels due to their low density, low cost and environmentally-friendly attributes. Based on a literature review of previous studies on natural fibres and their application in the automotive industry, this work investigates the mechanical characterization of various natural fibre composites with an Acrylonitrile Butadiene Styrene matrix (ABS). According to the literature review and the knowledge of the authors, the ratios of fibre and ABS presented have not yet been investigated. The tensile strength, impact strength and air flow resistivity of samples with different densities have been measured, and have been found to vary. In the conclusion some suggestions for the use of these natural fibre composites, for automotive applications, are reported. [ABSTRACT FROM AUTHOR]

To assess the utility of magnetic resonance imaging (MRI) in addition to the additive benefit of the conventional imaging techniques, computed tomography (CT) and nuclear medicine (NM) bone scintigraphy, for investigation of biochemical recurrence (BCR) post-prostatectomy where access to prostate specific membrane antigen (PSMA) positron-emission tomography (PET)-CT is challenging. Relevant imaging over a 5-year period was reviewed. Ethical approval was granted by the internal review board. All patients with suspected BCR, defined as a PSA ≥0.2 ng/ml on two separate occasions, underwent a retrospective imaging review. This was performed on PACS archive search database in a single centre using search terms "PSA" and "prostatectomy" in the three imaging methods; MRI, CT, and NM bone scintigraphy. All PSMA PET CT performed were recorded. One hundred and eighty-five patients were identified. Patients with an MRI pelvis that demonstrated distant metastases (i.e., pelvic bone metastases or lymph node involvement more cranial to the bifurcation of the common iliac arteries) were more likely to have a positive CT and/or NM bone scintigraphy. The Pearson correlation coefficient between the findings of M1 disease at MRI pelvis and the presence of distant metastases at CT thorax, abdomen, pelvis and NM bone scintigraphy was calculated at 0.81 (p< 0.01) and 0.91 (p< 0.01) respectively. An imaging strategy based on risk stratification and technique-specific selection criteria leads to more appropriate use of resources, and in turn, increases the yield of conventional imaging methods. MRI prostate findings can be used to predict the additive value of CT/NM bone scintigraphy allowing a more streamlined approach to their use. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the potential of Eucalyptus oils as green collectors in gold flotation was examined. Flotation tests were conducted on a sample of Boddington’s copper–gold sulfide ores. Eucalyptus oil compositions were determined by gas chromatography–mass spectrometry. Gold association of flotation products was investigated by Mineral Liberation Analyzer. It was found that Eucalyptus oils have the potential to replace potassium amyl xanthate as a collector in free gold flotation. The collecting power of Eucalyptus oils is correlated to the percentage of non-polar and weakly polar constituents, and in particular 1,8-cineole, phellendrene and pipertone. Eucalyptus oils possess strong selectivity for free gold rather than gold carriers, and therefore achieve high gold grades at the head of the flotation circuit. [Copyright &y& Elsevier]

Flash flotation is an important unit operation within many grinding circuits. It provides an opportunity for the valuable mineral to be recovered as early as possible in the processing plant. This prevents liberated valuable mineral from building up in the recirculating load of the mill, and reduces the occurrence of overgrinding. Overgrinding can place a significant limitation on overall recovery, because it causes the production of valuable fines that are difficult to recover by flotation.The flash flotation cell is fed by the cyclone underflow in a closed grinding circuit. This feed stream represents the optimal particle size distributions of valuable mineral and gangue for flotation kinetics, selectivity and grade. The flash cell treats the recirculating load of the ball mill, and therefore influences the performance of both the mill and the hydrocyclone classifier. The effect of a flash cell in the grinding circuit is difficult to determine since flash cells in Australia are introduced at the design stage and so no plant data is available before and after the introduction of the flash flotation unit. By establishing a computer simulation of the closed-circuit grinding with flash flotation, the interaction of flash flotation with grinding can be estimated. The models can be used to predict the effect of various changes to the operating conditions on circuit performance as well as the expected grinding performance in the absence of flash flotation. This enables the effect of flash flotation and any possible benefits to be evaluated.The model was developed from unit models of the ball milling, hydrocyclone classification and flash flotation processes. An empirical model was used for the flash cell, and generic models were fitted to the ball mill and hydrocyclone based on the matrix model and the Plitt model respectively. The data required for the development of the models was obtained from plant surveys of the Kanowna Belle gold mine and laboratory batch grinding and flotation tests.The model accurately represents the plant grinding and flash flotation circuit while operating under normal conditions. Simulation of the circuit using the model enabled the effect of variations to flash cell operating conditions on the flash concentrate, recirculating load and cyclone overflow to be determined. [Copyright &y& Elsevier]