Validation and setting up quality control for characterization of aluminum alloys in non‑ferrous fraction of auto‑shredders

ABSTRACT: The improvement of recycling rates of metal waste, namely those of end-of life vehicles, is nowadays becoming imperative. Aluminum and its alloys are the main metal components in non-ferrous fraction of auto-shredders separated out after sampling. Silicon, Mg, Cu, Zn, Mn, Ti, Fe and Cr are alloying elements, which allowed the identification and differentiation of Al alloys. Flame Atomic Absorption Spectrometry was used for quantification after HCl-HNO3 digestion, with the exception of Si, where HCl–HNO3–HF–H3BO3 digestion was used. Performance characteristics of measurement procedures, namely analytical dynamic ranges, limits of detection and quantification, precision and trueness were evaluated and measurement uncertainty estimated by applying an approach based on precision and trueness validation studies and quality control data. Target values, for repeatability, intermediate precision, trueness (recovery) and measurement uncertainty, were specified to differentiate Al alloys based on their own fit-for-purpose. Metrological traceability of the measurements results of the alloying elements was established by using certified values of British Chemical Standard (BCS) of Al alloys, BCS nº 181/1, BCS Nº 268. BCS Nº 300 and Standard Reference Material of Al-base alloy, SRM 87. The quantification of Si, Mg, Cu, Zn, Mn, Ti, Fe and Cr in aluminum alloys from the non-ferrous fraction of automatic crushers was determined successfully through the validated procedures.info:eu-repo/semantics/publishedVersio

Procedure validation and laboratory performance monitoring for the measurement of moisture, ash and volatile matter mass fractions in solid biofuels

Participation in interlaboratory comparisons is a requirement of the accreditation bodies for granting laboratory accreditation by EN ISO/IEC 17025:2005 as external quality control. Proficiency testing (PT) is used to demonstrate the individual performance of a laboratory for a specific test or measurement. Monitoring PT performance over time shows the continuing performance and allows the identification of potential problems related to random and systematic errors. In this study, it is shown that the procedures applied to measure mass fractions of moisture, ash and volatile matter in solid fuels fulfill the conditions stated in the European standards EN 14774-3, EN 14775 and EN 15148:2009 regarding target uncertainty, repeatability and reproducibility. Repeatability was assessed from sample duplicate analysis and combined standard uncertainty. Limits of detection and quantification were also estimated although no target values are stated. The obtained values fulfill the requirements for specifications and classes of solid biofuels. Laboratory performance over the time from 2011 to 2013 regarding such measurements was evaluated with 18 materials provided by WEPAL within the BIMEP program. Apart from monitoring the individual z-scores, their sequence was checked with summarizing parameters including the ‘rescaled sum z-scores’, RSZ, the ‘sum squared z-scores’, SSZ, and J-scores. For none of the analytes, the parameters indicated a trend over time and therefore it was not necessary to trigger any investigation or correcting procedure.

Evaluation of acid matrix effects in the determination of major elements in biomass by atomic absorption spectrometry from an environmentally friendly point of view

The estimation of major element content in solid biofuels is required for prediction and prevention of eventual ash-related problems during combustion. These analyses have to be achieved with minimum impact on the environment. The quantitation of Al, Ca, Mg, Na, K, Fe, Si and Mn in biofuels was carried out according to EN 15290 using acid decomposition of solid samples followed by atomic absorption spectrometry (AAS). A microwave-assisted acid digestion with a HNO3/H2O2/HF mixture was used, followed by HF complexation using H3BO3. Due to the presence of tetrafluoroboric acid complex in the digestion solution, matrix effects were noticed during elemental quantification by AAS. Standard addition calibration methods did not compensate for this matrix effect. Matrix effects that constrain an analytical response may be overcome by applying the procedure used for samples to the calibration standards using the same reagents. However, this entails using large amounts of toxic reagents. In this work, the fluoric–boric acid matrix matching was assessed statistically using one-way ANOVA tests. For the seven groups of nitric acid and reagent blank (HNO3/H2O2/HF/H3BO3) mixtures used, ranging from 0 to 1 volume ratios, no significant differences were observed for Si, Al, Fe and Mn. The calculated F values were lower than the critical value, F 6,14 = 2.85 (p = 0.05). However, for Ca, Mg, Na and K, significant differences were observed. Tenfold dilution was used for samples where the mass fraction exceeded the analytical dynamic range of the AAS instrument. The calibration solutions were prepared using the reagent blanks in the same proportion thus decreasing the amount of acids used. The procedure was validated using SRM 1573a—tomato leaves—purchased from the National Institute of Standards and Technology. Target recoveries of (1 ± 0.1) were achieved

Generalized commutation relations and Non linear momenta theories, a close relationship

A revision of generalized commutation relations is performed, besides a description of Non linear momenta realization included in some DSR theories. It is shown that these propositions are closely related, specially we focus on Magueijo Smolin momenta and Kempf et al. and L.N. Chang generalized commutators. Due to this, a new algebra arises with its own features that is also analyzed.Comment: accepted version in IJMP

BreastScreening: On the Use of Multi-Modality in Medical Imaging Diagnosis

This paper describes the field research, design and comparative deployment of a multimodal medical imaging user interface for breast screening. The main contributions described here are threefold: 1) The design of an advanced visual interface for multimodal diagnosis of breast cancer (BreastScreening); 2) Insights from the field comparison of single vs multimodality screening of breast cancer diagnosis with 31 clinicians and 566 images, and 3) The visualization of the two main types of breast lesions in the following image modalities: (i) MammoGraphy (MG) in both Craniocaudal (CC) and Mediolateral oblique (MLO) views; (ii) UltraSound (US); and (iii) Magnetic Resonance Imaging (MRI). We summarize our work with recommendations from the radiologists for guiding the future design of medical imaging interfaces.Comment: AVI 2020 Short Papers, 5 pages, 2 figures, for associated files, see https://github.com/MIMBCD-UI/avi-2020-short-pape

Water and wastewater monitoring of Guia Submarine Outfall: an 11 year survey

SANEST is a public sanitation company that manages a wastewater treatment plant located at Guia, on the west coast of Lisbon, Portugal. This company collects and treats the sewage of four municipalities with an estimated 750 000 population equivalent, thus being one of the biggest sanitation companies in Portugal. A Decision of the Commission 2001/720/CE conceded SANEST derogation, exempting it to apply less than secondary treatment to wastewaters discharged into the Atlantic Ocean from the four agglomerations. This decision was supported on a large monitoring program, presented to the EU, and set up by SANEST. It surveys the impact of the effluent disposal and includes measurements of physical, chemical, biological and microbiological properties in the effluent and in the receiving waters. This paper presents methods and results for the effluent chemical and microbiological quality as well as for the receiving waters and an ichthyofauna survey, and resumes an eleven year situation, with the preliminary wastewater treatment before effluent disposal. The WWTP results correspond to medium load urban effluents without treatment with temporal variability related to flood fluctuations. In the receiving waters almost legal values are respected and the plume of the outfall is only identifiable by faecal bacteria in the vicinity of the discharge. The fish community, in particular benthic species, has revealed a slight degradation probably due to the fact that pollutants tend preferentially to accumulate on sediment. The treatment plant is being upgraded to fulfil, by May 2009, an advanced primary treatment level that includes disinfection during the bathing season to fully observe the European Commission Decision 2001/720/EC

1-D Harmonic Oscillator in Snyder Space, the Classic and the Quantum

The 1-D dimension harmonic oscillator in Snyder space is investigated in its classical and quantum versions. The classical trajectory is obtained and the semiclassical quantization from the phase space trajectories is discussed. In the meanwhile, an effective cutoff to high frequencies is found. The quantum version is developed and an equivalent usual harmonic oscillator is obtained through an effective mass and an effective frequency introduced in the model. This modified parameters give us an also modified energy spectra.Comment: 8 pages, 2 figure