Semantic web technologies applied to software accessibility evaluation: a systematic literature review

Universal Access in the Information Society - Software accessibility is a current field of interest. Governments and organizations boost initiatives and legislations to assure universal access. On...     

FOS: a low-power cache organization for multicores

The Journal of Supercomputing - The cache hierarchy of current multicore processors typically consists of one or two levels of private caches per core and a large shared last-level cache. This...     

Microwave-assisted solution synthesis,microwave sintering and magnetic properties of cobalt ferrite

A simple, soft, and fast microwave-assisted hydrothermal method was used for the preparation of nanocrystalline cobalt ferrite powders from commercially-available Fe(NO₃)₃?9H₂O, Co(NO₃)₂?6H₂O, ammonium hydroxide, and tetrapropylammonium hydroxide (TPAH). The synthesis was conducted in a sealed-vessel microwave reactor specifically designed for synthetic applications, and the resulting products were characterized by XRD, FE-SEM, TEM, and HR-TEM. After a systematic study of the influence of the microwave variables (temperature, reaction time and nature of the bases), highly crystalline CoFe₂O₄ nanoparticles with a high uniformity in morphology and size, were directly obtained by heating at 130?°C for 20?min using the base TPAH. Dense ceramics of cobalt ferrite were prepared by non-conventional, microwave sintering of synthesized nanopowders at temperatures of 850–900?°C. The magnetic properties of both the nanopowders and the sintered specimens were determined in order to establish their feasibility as a permanent magnet.     

The Electron–Phonon Interaction of Low-Dimensional and Multi-Dimensional Materials from He Atom Scattering

Atom scattering is becoming recognized as a sensitive probe of the electron–phonon interaction parameter λ at metal and metal-overlayer surfaces. Here, the theory is developed, linking λ to the thermal attenuation of atom scattering spectra (in particular, the Debye–Waller factor), to conducting materials of different dimensions, from quasi-1D systems such as W(110):H(1 × 1) and Bi(114), to quasi-2D layered chalcogenides, and high-dimensional surfaces such as quasicrystalline 2ML-Ba(0001)/Cu(001) and d-AlNiCo(00001). Values of λ obtained using He atoms compare favorably with known values for the bulk materials. The corresponding analysis indicates in addition, the number of layers contributing to the electron–phonon interaction, which is measured in an atom surface collision.     

A Fluorometric Enzymatic Assay for Quantification of Steryl Glucosides in Biodiesel

Steryl glucosides (SG) are common contaminants in biodiesel that form precipitates, which form and cause problems due to fouling during transport and storage. Therefore, their quantification is necessary to assess the quality of this fuel. The methods currently available for SG analysis require expensive instrumentation, need a previous concentration step by solid‐phase extraction (SPE) or are of limited use for the quantitative assessment. We developed an enzymatic method for SG quantification in biodiesel samples based on the hydrolysis of the glucoside catalyzed by a broadly specific beta glucosidase and the subsequent determination of the glucose released by the reaction. The method is non‐expensive, sensitive and was adapted to 96‐well format fluorescence plate reader, making it useful for the parallel assay of multiple samples. The enzymatic assay presented here represent a valuable tool for both quality control and the development of improved biodiesel production and purification procedures.     

Bioactive Phytochemicals from Wild Arbutus unedo L. Berries from Different Locations in Portugal: Quantification of Lipophilic Components

The lipophilic composition of wild Arbutus unedo L. berries, collected from six locations in Penacova (center of Portugal), as well as some general chemical parameters, namely total soluble solids, pH, titratable acidity, total phenolic content and antioxidant activity was studied in detail to better understand its potential as a source of bioactive compounds. The chemical composition of the lipophilic extracts, focused on the fatty acids, triterpenoids, sterols, long chain aliphatic alcohols and tocopherols, was investigated by gas chromatography–mass spectrometry (GC–MS) analysis of the dichloromethane extracts. The lipophilic extractives of the ripe A. unedo berries ranged from 0.72% to 1.66% (w/w of dry weight), and consisted mainly of triterpenoids, fatty acids and sterols. Minor amounts of long chain aliphatic alcohols and tocopherols were also identified. Forty-one compounds were identified and among these, ursolic acid, lupeol, α-amyrin, linoleic and α-linolenic acids, and β-sitosterol were highlighted as the major components. To the best of our knowledge the current research study provides the most detailed phytochemical repository for the lipophilic composition of A. unedo, and offers valuable information for future valuation and exploitation of these berries.     

Estimation of mass-based composition in powder mixtures using Extended Iterative Optimization Technology (EIOT)

The Extended Iterative Optimization Technology (EIOT) method is proposed as an extension to Muteki's [I&ECR 2013;52(35):12258–12268] Iterative Optimization Technology to address deviations from Beer–Lambert's law in powders. The new method estimates the apparent spectrum for the pure species, rather than using the measured spectrum and augments Beer–Lambert's law with a bilinear term to capture the signature and strength of the nonchemical interferences. The proposed method has exhibited acceptable performance in spite of using a lean data set to estimate its parameters. The method provides robust and coherent estimates within the physical boundaries of the system and exhibits robustness to instrument transfer. The lean effort needed to build the EIOT method positions it as an attractive option in early stages of pharmaceutical drug product development. Its robustness to distinguish chemical from nonchemical signals implies a potential to lower the total cost of ownership for an EIOT-based solution in manufacturing. © 2018 American Institute of Chemical Engineers AIChE J, 65: 87–98, 2019