New multi-criteria LNN WASPAS model for evaluating the work of advisors in the transport of hazardous goods

Neural Computing and Applications - Successfully organizing the transport of hazardous materials and handling them correctly is a very important logistical task that affects both the overall flow...     

Nearly monotonic passband low‐pass filter design by using sum‐of‐squared Legendre polynomials

A new type of filter approximation, which utilizes orthonormal Legendre polynomials, referred to as sum‐of‐squared Legendre polynomials, is presented in this paper. Power transmission coefficient and the group delay of the proposed filter are compared with those of the Butterworth, Legendre–Papoulis, and Halpern filters. In order to illustrate the design of the proposed filter function, sum‐of‐squared Legendre polynomials coefficients and normalized element values of the low‐pass LC (inductor‐capacitor) ladder network prototype are given, up to the 10th degree. For continuous‐time domain filtering, doubly terminated LC ladder network topologies have very low sensitivities to changes of component values. In order to determine the effect of variation of all reactive components on the filter attenuation characteristic, the new sensitivity function has been proposed. Copyright © 2015 John Wiley & Sons, Ltd.     

Origin of Anomalous Bump at Low Temperatures in the c-Axis Optical Conductivity of High-T c Cuprates

The optical spectra of some high-Tc cuprates show anomalous bump around 450 cm ^–1 and dramatic phonon changes for E parallel to c axis, which grows at low temperatures. This phenomenon has been observed in Yba ₂ Cu ₃ O _6.6, YBa ₂ Cu ₄ O ₈ and Pb ₂ Sr ₂ RCu ₃ O ₈ , but not in (La,Sr) ₂ CuO ₄. In this study, we report the first observation of a similar anomaly in underdoped Bi ₂ Sr ₂ CaCu ₂ O ₈. The spectra were measured from two mosaics of Ba ₂ Sr ₂ CaCu ₂ O ₈ with T _c 80 K and 60 K. Considering that these spectral features seem to be common for all high-T _c cuprates with double CuO pyramids, we propose one plausible explanation that it is attributed to the second Josephson plasmon for intracell coupling in the Josephson coupled layer model.     

Determination of ultratrace levels of selenium in fruit and vegetable samples grown and consumed in Portugal

The selenium content in fruit and vegetable samples from two regions in Portugal were analysed using hydride generation atomic fluorescence spectrometry (HG-AFS) and radiochemical nuclear activation analysis (RNAA) – two analytical methods with very low limits of detection. The lower detection limits of HG-AFS, 3 μg kg⁻¹ and 8 μg kg⁻¹ (according to conditions used for digestion), and for RNAA, 10 μg kg⁻¹, meant that it was possible to determine selenium in samples previously analysed using the replicate sample instrumental nuclear activation analysis (RSINAA) with a higher detection limit associated.     

Alginate hydrogel microbeads incorporated with Ag nanoparticles obtained by electrochemical method

An innovative method was developed for production of alginate hydrogel microbeads incorporated with silver nanoparticles (AgNPs) based on electrochemical synthesis followed by electrostatic extrusion. AgNPs were synthesized galvanostatically at different values of AgNO₃ concentration in the initial solution (0.5–3.9 mM), current density (5–50 mA cm⁻²), and implementation time (0.5–10 min). Increase in all of these parameters increased the concentration of AgNPs in alginate solution and was confirmed by TEM analysis and UV–vis spectroscopy. Cyclic voltammetry studies and Fourier transform infrared spectroscopy proved the alginate to be a good capping agent for the electrochemical synthesis of silver nanoparticles, due to coordination bonding between hydroxyl and ether groups, as well as ring oxygen atoms in uronic acid residues of alginate molecules, and Ag nanoparticles. Ag/alginate colloid solution was used for production of uniform hydrogel microbeads (with diameter of 487.75 ± 16.5 μm) by electrostatic extrusion technique. UV–vis spectroscopy confirmed retention and entrapment of AgNPs in microbeads during the production process. Alginate microbeads incorporated with AgNPs are attractive as biocompatible carriers and/or efficient donors of AgNPs as active components especially for potential biomedical applications, which was demonstrated by the antibacterial activity against Staphylococcus aureus.