181 research outputs found

    Data-based control synthesis and performance assessment for moored wave energy conversion systems: the PeWEC case

    Get PDF
    With a model-based control strategy, the effectiveness of the associated control action depends on the availability of a representative control-oriented model. In the case of floating offshore wave energy converters (WECs), the device response depends upon the interaction between mooring system, any mechanical parts, and the hydrodynamics of the floating body. This study proposes an approach to synthesise WEC controllers under the effect of mooring forces building a representative data-based linear model able to include any relevant dynamics. Moreover, the procedure is tested on the moored pendulum wave energy converter (PeWEC) by means of a high-fidelity mooring solver, OrcaFlex (OF). In particular, the control action is computed with and without knowledge of the mooring influence, in order to analyse and elucidate the effect of the station-keeping system on the harvested energy. The performance assessment of the device is achieved by evaluating device power on the resource scatter characterising Pantelleria, Italy. The results show the relevance of the mooring dynamics on the device response and final set of control parameters and, hence, a significant influence of the station-keeping system on control synthesis and extracted mechanical power

    Acoustic cavitation by means ultrasounds in the extra virgin olive oil extraction process

    Get PDF
    Abstract The virgin olive oil extraction process has changed very little over the past 20 years when the mechanical crushers, malaxers, horizontal and vertical centrifuges, took place in the olive mills. However, malaxation process remains the main critical step due to the discontinuity of this process. In previous activities, the same authors demonstrated how application of new emerging technologies could offer an interesting number of advantages to remove this bottleneck and, among the others, the ultrasound (US) technology is the most promising one, due to its mechanical and thermal effects due to the acoustic cavitation phenomenon. Acoustic cavitation, provided by means of low frequency high power ultrasounds, increases the quality, the work capacity and efficiency of the extraction plant, guaranteeing the sustainability. The paper shows how the authors have designed, realized and tested the first in the world continuous ultrasonic full-scale device for the extra virgin olive oil industry, with the aim to obtain the best product quality at the highest efficiency. Considering the heterogeneity of the olive paste, which is composed of different tissues, and considering the large number of parameters able to influence the process, a 3D multiphase CFD analysis was used as auxiliary tool in the design a so-called Sono-Heat-Exchanger (SHE). This innovative device, to be placed between the crusher and the decanter, is a combination of a heat-exchanger with plate-shape ultrasonic transducers. Finally, experimental results about yields and phenols contents demonstrated the relevance of this innovation

    Wave energy converter mooring system: Available solvers and model validation

    Get PDF
    Talking about mooring systems for Wave Energy Converter shall be taken into account not only the station-keeping problem but also the influence of the mooring on the device motion. In literature several software for mooring modeling could be investigated, and among these software MoorDyn should be considered for its versatility. By the way, each model should be validated against experimental data to test its reliability hence, the aim of these paper is to follow the analysis which starts from an overview of the mooring system models and software and which ends with a model validation which has been performed against the experimental data obtained during Naples experimental campaign. Device kinematic has been recorded through a data acquisition system equipped in the scaled wave energy converter, and it has been used as input of the numerical simulation. The force recorded with a load cells system, connected with the mooring lines and the device, has been compared with the numerical one, derived from MoorDyn, and they have shown a marked overlapping that witnesses the validation

    Chemical behavior and in vitro activity of mixed phosphine gold(I)compounds on melanoma cell lines.

    Get PDF
    7partially_openCARUSO F; PETTINARI C; PADUANO F; VILLA R; MARCHETTI F; E. MONTI; ROSSI MCaruso, F; Pettinari, C; Paduano, F; Villa, R; Marchetti, F; Monti, ELENA CATERINA; Rossi, M

    Polymerized mixed aggregates containing gadolinium complex and CCK8 peptide.

    Get PDF
    Two novel amphiphilic unimers contg. an aliph. hydrophobic chain (PDA) with two C C triple bonds and hydrophilic heads presenting the chelating agent DTPAGlu and the CCK8 bioactive peptide, resp., have been prepd. by solid phase synthesis. Aggregates obtained by mixing together PDA-DTPAGlu, or its Gd(III) complex, and PDA-L2-CCK8 in 70/30 molar ratio before and after a polymn. process carried out by UV irradn. have been structurally characterized by means of small angle neutron scattering. The relaxivity properties of aggregates contg. Gadolinium complexes have also been investigated. Elongated mixed micelles have been obsd., in which the relaxivity value r1p for each Gadolinium complex, measured at 20 MHz and 298 K, is around 12 mM-1s-1

    Physicochemical properties of mixed micellar aggregates containing CCK peptides and Gd complexes designed as tumor specific contrast agents in MRI

    Get PDF
    New amphiphilic molecules containing a bioactive peptide or a claw moiety have been prepared in order to obtain mixed micelles as target-specific contrast agents in magnetic resonance imaging. The first molecule, C18H37CONH(AdOO)2-G-CCK8 (C18CCK8), contains a C18 hydrophobic moiety bound to the C-terminal cholecystokinin octapeptide amide (CCK 26-33 or CCK8). The second amphiphilic compound, C18H37CONHLys(DTPAGlu)CONH2 (C18DTPAGlu) or its gadolinium complex, (C18DTPAGlu- (Gd)), contains the same C18 hydrophobic moiety bound, through a lysine residue, to the DTPAGlu chelating agent. The mixed aggregates as well as the pure C18DTPAGlu aggregate, in the presence and absence of Gd, have been fully characterized by surface tension measurements, FT-PGSE-NMR, fluorescence quenching, and small-angle neutron scattering measurements. The structural characterization of the mixed aggregates C18DTPAGlu(Gd)-C18CCK8 indicates a spherical arrangement of the micelles with an external shell of 21 Å and an inner core of 20 Å. Both the DTPAGlu(Gd) complexes and the CCK8 peptides point toward the external surface. The measured values for relaxivity in saline medium at 20 MHz proton Larmor frequency and 25 °C are 18.7 mM-1 s-1. These values show a large enhancement in comparison with the isolated DTPAGlu(Gd) complex

    Safety and effectiveness of monochloramine treatment for disinfecting hospital water networks

    Get PDF
    The formation of potentially carcinogenic N-nitrosamines, associated with monochloramine, requires further research due to the growing interest in using this biocide for the secondary disinfection of water in public and private buildings. The aim of our study was to evaluate the possible formation of N-nitrosamines and other toxic disinfection by-products (DBPs) in hospital hot water networks treated with monochloramine. The effectiveness of this biocide in controlling Legionella spp. contamination was also verified. For this purpose, four different monochloramine-treated networks, in terms of the duration of treatment and method of biocide injection, were investigated. Untreated hot water, municipal cold water and, limited to N-nitrosamines analysis, hot water treated with chlorine dioxide were analyzed for comparison. Legionella spp. contamination was successfully controlled without any formation of N-nitrosamines. No nitrification or formation of the regulated DBPs, such as chlorites and trihalomethanes, occurred in monochloramine-treated water networks. However, a stable formulation of hypochlorite, its frequent replacement with a fresh product, and the routine monitoring of free ammonia are recommended to ensure a proper disinfection. Our study confirms that monochloramine may be proposed as an effective and safe strategy for the continuous disinfection of building plumbing systems, preventing vulnerable individuals from being exposed to legionellae and dangerous DBPs

    Characteristics and risk factors of isolated and quarantined children and adolescents during the first wave of SARS-CoV-2 pandemic: A cross-sectional study in Modena, Northern Italy

    Get PDF
    Background and aim: In early 2020, SARS-CoV-2 was declared a pandemic by the WHO and Italy was one of the first and most severely affected country in Europe. Despite the global interest about COVID-19 pandemic, several aspects of this infection are still unclear, especially in pediatric population. This study aims to investigate the characteristics of the isolated or quarantined children and adolescents followed by the Public Health Department of the Italian province of Modena during the first wave of COVID-19. Methods: The study population included all non-adult subjects aged 0-18 years who underwent isolation or quarantine during the first wave of SARS-CoV-2 pandemic from February 24 to June 18, 2020 in Modena province, Northern Italy. Results: In Modena province, 1230 children and adolescents were isolated in case of SARS-CoV-2 infection (6.3%), or quarantined due to close contact with confirmed cases (88.7%) or travelling from a high-risk area (5.0%). Among 349 individuals who underwent swab testing, 294 (84.2%) reported close contact with an infected cohabiting relative and 158 (45.3%) were symptomatic. Among all tested subjects, 78 (22.4%) resulted positive, with a higher proportion of symptomatic subjects compared with the SARS-CoV-2-negative (78.2% vs. 35.8%). Fever was mostly present in SARS-CoV-2-positive children (48.7% vs. 12.6%). Both anosmia (58.3% vs. 41.7%) and dysgeusia (54.5% vs. 45.5%) had only slightly higher frequency in SARS-CoV-2-positive. Conclusions: These findings allow to expand the knowledge regarding characteristics of non-adult subjects isolated or quarantined during the first wave of SARS-CoV-2 pandemic. (www.actabiomedica.it)

    LA FLORA E LA MESOFAUNA DI SATRIANUM

    Get PDF
    Il sito di Satrianum si dispone tra le due vallate del Melandro e del Noce, in connessione con un’articolata rete idrografica facente capo ai fiumi Agri e Basento . Tutta l’area che circonda l’altura, è caratterizzata da terreni che si dispiegano tra gli 800 e i 600 m. s.l.m., e presenta un habitat montano ideale per le colture cerealicole, per le distese boschive e per la pastorizia. Notizie del sito si attestano fin dall’età altomedievale (Agiografia di San Laviero, 1162). In età normanna la città aveva un dominus e la sede vescovile come testimoniano le fonti documentarie. L’impianto insediativo si presenta racchiuso da mura di cinta, con all’ interno, oltre alle strutture abitative, i due poli del potere politico e religioso: la torre, a pianta quadrata, ubicata in posizione decentrata rispetto all’insediamento, e la cattedrale. L’abbandono di Satrianum avvenne nel corso del XV secolo, probabilmente a seguito di un grave evento sismico ma continuò ad essere frequentato in maniera sporadica fino al XVIII secolo. Nell’ottica di comprendere e ricreare un ambiente passato è stata effettuata una ricognizione e l’identificazione della flora e della mesofauna esistente. Alla fine è stato realizzato un erbario e un insettario
    • …
    corecore