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Magnetic Josephson junctions (MJJs) are a special class of hybrid systems where antagonistic correlations coexist, thus providing a key for advances in weak superconductivity, superconducting spintronics, and quantum computation. So far, the memory properties of MJJs have been mostly investigated in view of digital electronics and for spintronic devices at liquid-helium temperature. At the operating temperature of quantum circuits, a magnetic order can rise in a superconductor (S) at the S/ferromagnet (F) interface, i.e., the inverse proximity effect (IPE), thus leading to a significant modification of the magnetic field patterns in MJJs. In this work, we have carried out a comparative investigation of the magnetic behavior of tunnel MJJs with a strong ferromagnetic layer inserted in the layout of both Nb and Al JJs, respectively. The comparative analysis validates the crucial role of the temperature, the fundamental scaling energies of S/F coupling systems, and the transparency of the S/F interface. This investigation points out that the IPE is a key aspect to consider when designing tunnel MJJs operating well below 4 K and thus in the perspective of hybrid superconducting quantum architectures. [ABSTRACT FROM AUTHOR]

With the prospective of developing an integrated monitoring system aimed at assessing whether a landing gear has experienced hard impact during the approach, a dedicated method is developed aimed at determining vertical speed by means of strain measurement via FBG strain sensors. Representative impacts on simple structural elements have been reproduced in laboratory, as aluminum slender beams of different lengths were dropped from given heights onto a steel plate base. Contact velocities have been estimated by deformations detection. [ABSTRACT FROM AUTHOR]

The aim of this research is investigation of FeNi bimetallic nanoparticles effectiveness after their using in the reduction of the high nitrate concentration. The advantage of the reusability is opportunity to create cost effective and environmentally friendly technologies. In this paper the efficiency of the same bimetallic nanoparticles was described. The same nanoparticles were used for nitrate reduction in the first, second and third times. After each use they were collected and used again for reduction of 300 mg L−1 nitrates. Fe/Ni based bimetallic nanoparticles were synthesized freshly and used for nitrate removal. Synthesis of bimetallic nanoparticles was carried out in the presence of sodium oleate as dispersing agent by widely known borohydride reduction method. Batch experiments were performed on nitrate contaminated water samples. The parameters investigated were the reaction pH (acidic, alkaline conditions) and nitrates concentration after their reusing. The results showed that the total nitrate reduction (99.75%) was occurred after 5 min of reaction in the presence of freshly synthesized nanoparticles. Then the same nanoparticles were repeatedly used for nitrate reduction. This test has been performed thrice to study nanoparticles effectiveness after each use. It was investigated that the efficiency of nitrate degradation decreased after reusing. The second remediation by the same nanoparticles consisted 64.67% of nitrates removal and the third one – 47%. To evaluate the nitrate reduction rate and the kinetic of reaction, additional tests were performed at different temperatures. The structural characterization of freshly synthesized and reused bimetallic nanoparticles was investigated by TEM. Results showed that bimetallic nanoparticles were covered with an oxide layer after nitrates reduction. Decreased efficiency of reused bimetallic nanoparticles can be due to the appearance of an oxide layer. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.02.018 Byline: L. Di Palma, P. Ferrantelli, F. Medici Abstract: The optimum conditions for the recovery of copper from a contaminated soil by using the soil flushing technique are evaluated. Tests on a soil artificially contaminated with copper chloride were carried out in order to evaluate the influence of the speed of percolation and of the chelating agent concentration (aqueous solution of an ethylendiaminotetraacetic acid di-sodium salt Na.sub.2-EDTA). At pH=7.3 an efficiency up to 93.9% for copper extraction was achieved by flushing 500ml of Na.sub.2-EDTA 0.05M solution and 100ml of pure water at 0.792cm/h. At these operating conditions the formation of EDTA complexes with other competitive cations (calcium and iron) was negligible. The experimental results were in agreement with the ones obtained using a model describing the chemistry of metal extraction. This model assessed that above pH=6 the formation of calcium and iron EDTA complexes was excluded and only the chelation of copper was allowed. The recovery of 91.6% of EDTA was also achieved by evaporating and acidifying the extracted solution: after filtration, solid EDTA was obtained, through the addition of sodium hydroxide Na.sub.2-EDTA. About 99.5% of the extracted copper was finally precipitated under alkaline conditions from the liquid phase. Author Affiliation: Dipartimento di Ingegneria Chimica dei Materiali delle Materie Prime e Metallurgia-Universita di Roma 'La Sapienza', via Eudossiana 18, 00184 Roma Article History: Received 15 July 2004; Revised 13 November 2004; Accepted 10 February 2005