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Ad oggi si sente sempre più spesso parlare del problema del surriscaldamento globale dovuto ad un sempre maggiore inquinamento atmosferico da parte delle industrie, agricoltura, automobili ecc., tutto ciò sta portando il nostro pianeta a frequenti e pericolosi disastri ambientali. Molti studi infatti evidenziano che se non ci sarà un inversione di tendenza arriveremo ad un punto di non ritorno oltre il quale la Terra arriverà al collasso. Ad oggi tra le tecnologie in uso per ridurre questo fenomeno la più utilizzata risulta la “Carbon Capture and Storage” la quale nonostante sia stata ampiamente sviluppata, questa risulta estremamente costose e richiedono molta energia. Essa rappresenta semplicemente una soluzione temporanea, che rende irrealizzabile uno sviluppo completo sulla scala richiesta .Una soluzione tecnologica che sta dando risultati incoraggianti circa la cattura dell’anidride carbonica è la “Biological Carbon Capture and Utilizations”. Quest’ultima consiste nel bio-sequestro della CO attraverso fabbriche di cellule microalgali, le quali poi potranno essere utilizzata per la produzione di biofuel, bioenergia e altri prodotti a valore aggiunto

To significantly increase the sampling rate of an ADC, timeinterleaved ADC (TIADC) is an efficient solution. Due to the manufacturing process, the main drawback of a TIADC system is that the M ADCs, which compose this end, are not exactly the same. This means that offset, gain and time mismatch errors are introduced. These errors cause distortions in the output sampled signal and introduce unwanted tones and noise, and hence, reduce the spurious free dynamic range (SFDR) as well as the signal to noise ratio (SNR). In this paper, we propose a new orthogonal digital calibration implementation, for timing skew, offset and gain mismatches, based on Code Division Multiple Access (CDMA) technique. Our calibration is online, this means that errors can be estimated while the ADC is running. Since most of the calibration processes are carried out on the digital outputs, very little change is needed on the analog part of the ADC. Simulation and implementation results show respectively the efficiency of our proposed calibration algorithm and our hardware implementation.

This paper surveys the capability of the hybrid laser-arc welding in comparison with lone laser welding for AA2198 aluminum alloy experimentally. In the present research, a continuous Nd:YAG laser with a maximum power of 2000 W and a 350 A electric arc were used as two combined welding heat sources. In addition to the lone laser welding experiments, two strategies were examined for hybrid welding; the first one was low laser power (100 W) accompanied by high arc energy, and the second one was high laser power (2000 W) with low arc energy. Welding speed and arc current varied in the experiments. The influence of heat input on weld pool geometry was surveyed. The macrosection, microhardness profile and microstructure of the welded joints were studied and compared. The results indicated that in lone laser welding, conduction mode occurred and keyhole was not formed even in low welding speeds and thus the penetration depth was so low. It was also found that the second approach (high laser power accompanied with low arc energy) is superior to the first one (low laser power accompanied with high arc energy) in hybrid laser-arc welding of Al2198, since lower heat input was needed for full penetration weld and as a result a smaller HAZ was created. © 2017 Elsevier Ltd

Human studies have consistently shown that drugs of abuse affect memory function. The psychostimulants amphetamine and the “bath salt” 3,4-methylenedioxypyrovalerone (MDPV) increase brain monoamine levels through a similar, yet not identical, mechanism of action. Findings indicate that amphetamine enhances the consolidation of memory for emotional experiences, but still MDPV effects on memory function are underinvestigated. Here, we tested the effects induced by these two drugs on generalization of fear memory and their relative neurobiological underpinnings. To this aim, we used a modified version of the classical inhibitory avoidance task, termed inhibitory avoidance discrimination task. According to such procedure, adult male Sprague–Dawley rats were first exposed to one inhibitory avoidance apparatus and, with a 1-min delay, to a second apparatus where they received an inescapable footshock. Forty-eight hours later, retention latencies were tested, in a randomized order, in the two training apparatuses as well as in a novel contextually modified apparatus to assess both strength and generalization of memory. Our results indicated that both amphetamine and MDPV induced generalization of fear memory, whereas only amphetamine enhanced memory strength. Co-administration of the β-adrenoceptor antagonist propranolol prevented the effects of both amphetamine and MDPV on the strength and generalization of memory. The dopaminergic receptor blocker cis-flupenthixol selectively reversed the amphetamine effect on memory generalization. These findings indicate that amphetamine and MDPV induce generalization of fear memory through different modulations of noradrenergic and dopaminergic neurotransmission.