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41.
We characterize and discuss the identifiability condition for quantum process tomography, as well as the minimal experimental resources that ensure a unique solution in the estimation of quantum channels, with both direct and convex optimization methods. A convenient parametrization of the constrained set is used to develop a globally converging Newton-type algorithm that ensures a physically admissible solution to the problem. Numerical simulation is provided to support the results and indicate that the minimal experimental setting is sufficient to guarantee good estimates. 相似文献
42.
Marco Baldi Franco Chiaraluce Nicola Maturo Giacomo Ricciutelli Alessandro Ardito Francesco Barbaglio Stefano Finocchiaro Lorenzo Simone Ricard Abell Javier De Vicente Mattia Mercolino 《International Journal of Satellite Communications and Networking》2019,37(6):571-587
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts. 相似文献
43.
44.
Mattia Zanni Alessandro Morri Lorella Ceschini 《Fatigue & Fracture of Engineering Materials & Structures》2022,45(1):113-132
A new model for the high cycle notch fatigue strength prediction of tool steels subjected to axial loading is proposed, based on previous literatures studies and experimental tests carried out on six different tool steels, including rotating bending fatigue tests on notched specimens, fractographic analyses, hardness, residual stress, and roughness measurements. The novelty is the assumption that surface defects are the main cause of notch fatigue failures of such steels. A probabilistic approach was implemented by modeling size distributions of defects, resulting in the prediction of normal distributions of fatigue strength. Like to other previous models, the effect of steel hardness, surface residual stress, notch severity, and specimen size was also taken into account. Model calibration and validation were performed using the data collected by the experimental activity. Model behavior was investigated by performing a sensitivity analysis, aiming to verify the response to variations of the considered input variables. Prediction errors of only 1.3% (on average) and 3.1% (maximum) resulted from the comparison between model-predicted and experimental notch fatigue strength. 相似文献
45.
Mattia Biesuz Woinshet D. Abate Vincenzo M. Sglavo 《Journal of the American Ceramic Society》2018,101(1):71-81
Porcelain stoneware was consolidated by flash sintering under DC polarization using current densities in the range 4‐20 mA/mm2. The results show the applicability of this innovative sintering technology to a material whose densification occurs by vitrification, thus allowing to extend the possible application field of flash sintering to traditional ceramics. Using appropriate current density, the flash‐ sintered samples are dense, homogeneous, and well‐vitrified. XRD and microstructural analysis points out the formation of primary mullite while secondary mullite is only sporadically observed. In addition, comparison between flash sintering and fast firing shows that the densification obtained in the selected ceramic system via the former route cannot be reproduced just by a rapid heating process. 相似文献
46.
Sintering behavior of Ba/Sr celsian precursor obtained from zeolite‐A by ion‐exchange method
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Mattia Biesuz Luca Spiridigliozzi Antonello Marocco Gianfranco Dell'Agli Vincenzo M. Sglavo Michele Pansini 《Journal of the American Ceramic Society》2017,100(12):5433-5443
(Ba, Sr)‐exchanged zeolite A with composition Ba0.74Sr0.22Na0.04Al2Si2O8 was prepared by cation exchange; a mild thermal treatment converts into an amorphous phase. Successive crystallization and sintering behavior was studied by XRD, DTA, and thermodilatometric analysis. The results point out the activation of viscous flow sintering mechanisms between 900°C and 1050°C. The densification process starts when the amorphous phase reaches its glass transition temperature (897°C) and finishes when the material crystallizes forming hexacelsian. The application of an external pressure in such temperature range allows to achieve an almost complete densification, the material transforming at 1300°C into dense monoclinic celsian much below the typical processing temperature. 相似文献
47.
Integration of biofuels intermediates production and nutrients recycling in the processing of a marine algae 总被引:1,自引:0,他引:1
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Ali Teymouri Sandeep Kumar Elena Barbera Eleonora Sforza Alberto Bertucco Tomas Morosinotto 《American Institute of Chemical Engineers》2017,63(5):1494-1502
The cost‐effective production of liquid biofuels from microalgae is limited by several factors such as recovery of the lipid fractions as well as nutrients management. Flash hydrolysis, a rapid hydrothermal process, has been successfully applied to fractionate the microalgal biomass into solid biofuels intermediates while recovering a large amount of the nutrients in the aqueous phase (hydrolyzate) in a continuous flow reactor. The aim of the work is to enhance the quality of a high‐ash containing marine algae Nannochloropsis gaditana as biofuel feedstock while recycling nutrients directly for algae cultivation. Characterization of products demonstrated an increase in extractable lipids from 33.5 to 65.5 wt % (dry basis) while retaining the same fatty acid methyl ester profile, in addition to diminution of more than 70 wt % of ash compared to raw microalgae. Moreover, the hydrolyzate was directly used to grow a microalga of the same genus. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1494–1502, 2017 相似文献
48.
A New Formulation Based on Ozonated Sunflower Seed Oil: In Vitro Antibacterial and Safety Evaluation
Francesca Serio Graziano Pizzolante Giuseppe Cozzolino Maria D’Alba Francesco Bagordo Mattia De Giorgi 《臭氧:科学与工程》2017,39(3):139-147
The objective of this study was to investigate the potential in vitro biological properties of Oz.Or.Oil 30, a new formulation composed of 30% ozonated sunflower seed oil, which is believed to keep skin smooth and moisturized, supporting repair processes, tissue regeneration and re-epithelialization of wounds. The antibacterial activity, the qualitative and quantitative evaluation of the cytotoxic effect of the formulation on cultures of Vero cells and 3T3 fibroblasts showed that Oz.Or.Oil 30 merits further in vivo study using clinical-laboratory correlations, because it could be suggested as an alternative therapy against bacterial and fungal diseases. 相似文献
49.
Jhon?Alexander?Gomez CaicedoEmail author Oscar?E.?Mattia Hamilton?Klimach Sergio?Bampi 《Analog Integrated Circuits and Signal Processing》2016,88(2):333-345
This work presents a resistorless self-biased and small area sub-bandgap voltage reference that works in the nano-ampere consumption range with 0.75 V of power supply. The circuit applies a curvature compensation technique that allows an extended temperature range without compromising the temperature stability. The behavior of the circuit is analytically described, and a design methodology is proposed which allows the separate adjustment of the bipolar junction transistor bias current and its curvature compensation. Simulation results are presented for a 180 nm CMOS process, where a reference voltage of 469 mV is designed, with a temperature coefficient of 5 ppm/°C for the ?40 to 125 °C extended temperature range. The power consumption of the whole circuit is 16.3 nW under a 0.75 V power supply at 27 °C. The estimated silicon area is 0.0053 mm2. 相似文献
50.
Amedeo Biasi Valerio Marino Giuditta Dal Cortivo Paolo Enrico Maltese Antonio Mattia Modarelli Matteo Bertelli Leonardo Colombo Daniele DellOrco 《International journal of molecular sciences》2021,22(19)
Guanylate cyclase-activating protein 1 (GCAP1), encoded by the GUCA1A gene, is a neuronal calcium sensor protein involved in shaping the photoresponse kinetics in cones and rods. GCAP1 accelerates or slows the cGMP synthesis operated by retinal guanylate cyclase (GC) based on the light-dependent levels of intracellular Ca2+, thereby ensuring a timely regulation of the phototransduction cascade. We found a novel variant of GUCA1A in a patient affected by autosomal dominant cone dystrophy (adCOD), leading to the Asn104His (N104H) amino acid substitution at the protein level. While biochemical analysis of the recombinant protein showed impaired Ca2+ sensitivity of the variant, structural properties investigated by circular dichroism and limited proteolysis excluded major structural rearrangements induced by the mutation. Analytical gel filtration profiles and dynamic light scattering were compatible with a dimeric protein both in the presence of Mg2+ alone and Mg2+ and Ca2+. Enzymatic assays showed that N104H-GCAP1 strongly interacts with the GC, with an affinity that doubles that of the WT. The doubled IC50 value of the novel variant (520 nM for N104H vs. 260 nM for the WT) is compatible with a constitutive activity of GC at physiological levels of Ca2+. The structural region at the interface with the GC may acquire enhanced flexibility under high Ca2+ conditions, as suggested by 2 μs molecular dynamics simulations. The altered interaction with GC would cause hyper-activity of the enzyme at both low and high Ca2+ levels, which would ultimately lead to toxic accumulation of cGMP and Ca2+ in the photoreceptor outer segment, thus triggering cell death. 相似文献