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Statistical analysis of physico-mechanical parameters of sandstones occurring in orogenic settings

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Journal of Mountain Science 2024年第4期21卷 1388-1402页

作者： PAPPALARDO Giovanna CARBONE Serafina MONACO Carmelo ZOCCO Giordana MINEO Simone dipartimento di Scienze Biologiche Geologiche E AmbientaliUniversitàDegli Studi Di CataniaCorso Italia 5795129 CataniaItaly

In northeastern Sicily(Italy),sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic *** being part of the same geological formation,these sandstones are characterized by highly different features in terms of texture and physico-mechanical *** poses a scientific question on the possibility of tracing these rocks to a single statistical model,which could be representative of their main engineering geological ***,it is worth investigating on the possible reasons of such differences,that should be searched either in the current geographical sandstone distribution or in the rock *** this study,sandstone samples were collected from different sites and were analyzed at both the hand and thin section *** sandstone types were recognized,characterized by a different ***,the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties,such as porosity,density,mechanical strength,deformability,and ultrasonic *** rock mechanical strength proved linked to the rock compactness and to the presence of lithic fragments,while pores and a pseudo-matrix between grains represent weakening *** data were also statistically analyzed by grouping the specimens according to a geographical criterion,with respect to their sampling area,but no link was found between location and rock ***,with the aim of achieving mathematical laws that could be used to predict some rock properties from others,useful for practical purposes when dealing with such a high property variability,single and multiple regression analyses were carried *** show that the Uniaxial Compressive Strength,porosity,and P-wave velocity are the best predictors for a quick,indirect estimation of the main physico-mechanical *** methodological approach developed for this research can be taken as reference to study other world

关键词： Sandstone Laboratory test Uniaxial Compressive Strength Porosity Rocks

Minimal Free Resolutions of Zero-dimensional Schemes in P1 ×P1

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Algebra Colloquium 2015年第1期22卷 97-108页

作者： Paola Bonacini Lucia Marino universita degli studi di catania ViMe A. Doria 6 95125 Catania Italy

Let X be a zero-dimensional scheme in p1 × p1. Then X has a minimal free resolution of length 2 if and only if X is ACM. In this paper we determine a class of reduced schemes whose resolutions, similarly to the ACM case, can be obtained by their Hilbert functions and depend only on their distributions of points in a grid of lines. Moreover, a minimal set of generators of the ideal of these schemes is given by curves split into the union of lines.

关键词： resolution Hilbert function separators

The cold chain and the COVID-19 pandemic:an unusual increase in histamine content in fish samples collected in Southern Italy during lockdown

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Food Quality and Safety 2021年第4期5卷 329-335页

作者： Francesco Giuseppe Gailuzzo Gaetano Cammilleri Antonello Cicero Licia Pantano Andrea Pulvirenti Andrea Macaluso Nicola Cicero Vittorio Calabrese Vincenzo Ferrantelli Istituto Zooprofilattico Sperimentale della Sicilia PalermoItaly dipartimento di Scienze della Vita Universita degli studi di Modena e Reggio EmiliaModenaItaly dipartimento SASTAS Universita degli studi di MessinaMessinaItaly dipartiment'o di Scienze biomediche e biotecnologiche Universita degli studi di CataniaCataniaItaly

Objectives:We analysed 900 samples of fresh(250)and processed(650)fish products collected in Sicily(Southern Italy)in 2020 during the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)pandemic(hereafter:COVID-19).Materials and methods:The samples were divided temporally based on four phases relating to the various restrictions imposed by the Italian government in this *** validated method of ultrahigh-performance liquid chromatography combined with a diode array detector was then employed for the ***:The samples collected during the Phase I lockdown period and after it had ended(Phase II)revealed significant increases in the mean histamine levels:(41.89±87.58)mg/kg and(24.91±76.76)mg/kg,*** 11(1.3%of the total)fresh fish samples that were identified as being non-compliant with Regulation(EC)No.2073/2005 were only found during these two *** the processed samples were always *** histamine values decreased as the restrictions eased,achieving a mean value of(11.16±9.3)mg/kg(Phase III).Conclusions:There was an increase in the incidence offish samples that were non-compliant with Regulation(EC)No.2073/2005 compared to previous surveillance *** results provide a first report on the effect of lockdown measures on food safety and the cold *** findings must cause food safety operators to intensify their controls over fresh fish products in such periods to safeguard consumer *** studies are required to evaluate whether the same trend would be observed with other food contaminants.

关键词： Histamine cold-chain food safety COVID-19

Synthesis, Properties and Potential Applications of Porous Graphene: A Review

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Nano-Micro Letters 2013年第4期5卷 260-273页

作者： Paola Russo Anming Hu Giuseppe Compagnini Department of Mechanical and Mechatronics Engineering University of Waterloo dipartimento di Scienze Chimiche Università degli Studi di Catania Institute of Laser Technology Beijing University of Technology

Since the discovery of graphene, many efforts have been done to modify the graphene structure for integrating this novel material to nanoelectronics, fuel cells, energy storage devices and in many other applications. This leads to the production of different types of graphene-based materials, which possess properties different from those of pure graphene. Porous graphene is an example of this type of materials. It can be considered as a graphene sheet with some holes/pores within the atomic plane. Due to its spongy structure, porous graphene can have potential applications as membranes for molecular sieving, energy storage components and in nanoelectronics. In this review, we present the recent progress in the synthesis of porous graphene. The properties and the potential applications of this new material are also discussed.

关键词： Graphene Porous graphene Gas separation Energy storage

Awake laparoscopic cholecystectomy:A case report and review of literature

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World Journal of Clinical Cases 2023年第13期11卷 3002-3009页

作者： Chiara Mazzone Maria Sofia Iacopo Sarvà Giorgia Litrico Andrea Maria Luca di Stefano Gaetano La Greca Saverio Latteri dipartimento di Scienze Mediche Chirurgiche e Tecnologie Avanzate"G.F.Ingrassia"Universitàdegli Studi di CataniaCatania 95123Italy

BACKGROUND Laparoscopic cholecystectomy(LC)is one of the most widely practiced surgical procedures in abdominal *** undergo LC during general anaesthesia;however,in recent years,several studies have suggested the ability to perform LC in patients who are *** report a case of awake LC and a literature *** SUMMARY A 69-year-old patient with severe pulmonary disease affected by cholelithiasis was scheduled for LC under regional *** first performed peridural anaesthesia at the T8-T9 level and then spinal anaesthesia at the T12-L1 *** procedure was managed in total comfort for both the patient and the *** intra-abdominal pressure was 8 *** patient remained stable throughout the procedure,and the postoperative course was *** Evidence has warranted the safe use of spinal and epidural anaesthesia,with minimal side effects easily managed with *** anaesthesia in selected patients may provide some advantages over general anaesthesia,such as no airway manipulation,maintenance of spontaneous breathing,effective postoperative analgesia,less nausea and vomiting,and early ***,this technique for LC is not widely used in Europe;this is the first case reported in Italy in the *** anaesthesia is feasible and safe in performing some types of laparoscopic *** studies should be carried out to introduce this type of anaesthesia in routine clinical practice.

关键词： Laparoscopic cholecystectomy Awake surgery Awake laparoscopy Gallstone disease Regional anaesthesia Spinal anesthesia Case report

direct Simulation of Charge Transport in Graphene Nanoribbons

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Communications in Computational Physics 2022年第2期31卷 449-494页

作者： Giovanni Nastasi V.Dario Camiola Vittorio Romano universita degli studi di catania Dipartimento di Matematica e InformaticaViale Andrea Doria 695125 CataniaItaly

Graphene nanoribbons are considered as one of the most promising ways to design electron devices where the active area is made of *** fact,graphene nanoribbons present a gap between the valence and the conduction bands as in standard semiconductors such as Si or GaAs,at variancewith large area graphenewhich is gapless,a feature that hampers a good performance of graphene field effect *** use graphene nanoribbons as a semiconductor,an accurate analysis of their electron properties is ***,electron transport in graphene nanoribbons is investigated by solving the semiclassical Boltzmann equation with a discontinuous Galerkin *** the electron-phonon scattering mechanisms are *** adopted energy band structure is that devised in[1]while according to[2]the edge effects are described as an additional scattering stemming from the Berry-Mondragon model which is valid in presence of edge *** this approach a spacial 1D transport problem has been solved,even if it remains two dimensional in the wavevector space.A degradation of charge velocities,and consequently of the mobilities,is found by reducing the nanoribbon width due mainly to the edge scattering.

关键词： Graphene nanoribbons bipolar charge transport discontinuous Galerkin method

Simulation of Bipolar Charge Transport in Graphene by Using a discontinuous Galerkin Method

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Communications in Computational Physics 2019年第6期26卷 114-134页

作者： Armando Majorana Giovanni Nastasi Vittorio Romano Department of Mathematics and Computer Science Universita degli Studi di Cataniaviale Andrea Doria 695125 CataniaItaly

Charge transport in suspended monolayer graphene is simulated by a numerical deterministic approach,based on a discontinuous Galerkin(DG)method,for solving the semiclassical Boltzmann equation for *** the conduction and valence bands are included and the interband scatterings are taken into *** use of a direct Simulation Monte Carlo(DSMC)approach,which properly describes the interband scatterings,is computationally very expensive because the va-lence band is very populated and a huge number of particles is *** the choice of simulating holes instead of electrons does not overcome the problem because there is a certain degree of ambiguity in the generation and recombination terms of electron-hole ***,direct solutions of the Boltzmann equations with a DSMC neglect the interband scatterings on the basis of physical *** DG approach does not suffer from the previous drawbacks and requires a reasonable computing *** the present paper the importance of the interband scatterings is accurately evaluated for several values of the Fermi energy,addressing the issue related to the validity of neglecting the generation-recombination *** is found out that the inclusion of the interband scatterings produces huge variations in the average values,as the current,with zero Fermi energy while,as expected,the effect of the interband scattering becomes negligible by increasing the absolute value of the Fermi energy.

关键词： Graphene bipolar charge transport discontinuous Galerkin method

Strongly enhanced light trapping in a two-dimensional silicon nanowire random fractal array

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Light(Science & Applications) 2016年第1期5卷 855-861页

作者： Barbara Fazio Pietro Artoni Maria Antonia Iatì Cristiano D’Andrea Maria JosèLo Faro Salvatore Del Sorbo Stefano Pirotta Pietro Giuseppe Gucciardi Paolo Musumeci Cirino Salvatore Vasi Rosalba Saija Matteo Galli Francesco Priolo Alessia Irrera CNR-IPCF Istituto per i Processi Chimico Fisici98158 MessinaItaly dipartimento di Fisica e Astronomia Universitàdi Catania95123 CataniaItaly CNR-MATIS IMM Istituto per la Microelettronica e Microsistemi95123 CataniaItaly dipartimento di Fisica Universitàdegli Studi di Pavia27100 PaviaItaly dipartimento di Scienze Matematiche e Informatiche Scienze Fisiche e Scienze della TerraUniversitàdi Messina98166 MessinaItaly Scuola Superiore di catania Universitàdi Cataniavia Valdisavoia995123 CataniaItaly

We report on the unconventional optical properties exhibited by a two-dimensional array of thin Si nanowires arranged in a random fractal geometry and fabricated using an inexpensive,fast and maskless process compatible with Si *** structure allows for a high light-trapping efficiency across the entire visible range,attaining total reflectance values as low as 0.1%when the wavelength in the medium matches the length scale of maximum heterogeneity in the *** show that the random fractal structure of our nanowire array is responsible for a strong in-plane multiple scattering,which is related to the material refractive index fluctuations and leads to a greatly enhanced Raman scattering and a bright *** strong emissions are correlated on all length scales according to the refractive index *** relevance and the perspectives of the reported results are discussed as promising for Si-based photovoltaic and photonic applications.

关键词： light trapping multiple scattering Raman enhancement random fractal silicon nanowires

Complexation of As(Ⅲ)by phosphonate ligands in aqueous fluids:Thermodynamic behavior,chemical binding forms and sequestering abilities

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Journal of Environmental Sciences 2020年第8期32卷 100-110页

作者： Donatella Chillè Donatella Aiello Giuseppa Ida Grasso Ottavia Giuffrè Anna Napoli Carmelo Sgarlata Claudia Foti dipartimento di Scienze Chimiche BiologicheFarmaceutiche ed AmbientaliUniversitàdi MessinaViale F.Stagno d’Alcontres 3198166 MessinaItaly dipartimento di Chimica e Tecnologie Chimiche Universitàdella CalabriaVia P.Bucci87036 Arcavacata di Rende(CS)Italy dipartimento di Scienze Chimiche Universitàdegli Studi di CataniaViale A.Doria 695125 CataniaItaly

In recent years,the contamination of water by arsenic reached alarming levels in many countries of the world,attracting the interest of many researchers engaged in testing methodologies able to remove this harmful *** important aspect that must be taken into consideration is the possibility to find arsenic in different chemical forms which could require different approaches for its *** this aim,a speciation analysis appears to be crucial for better understanding the behavior of arsenic species in aqueous solutions,especially in presence of compounds with marked chelating *** can be identified as good sequestering agents and,at this purpose,this manuscript intends to investigate the interaction of As(Ⅲ)with three phosphonic acids derived from nitrilotriacetic acid(NTA)by replacements of one(N-(Phosphonomethyl)iminodiacetic acid,NTAP),two(N,N-Bis-(phosphonomethyl)glycine,NTA2P)and three(Nitrilotri(methylphosphonic acid),NTA3P)carboxylic groups with the same number of phosphonate *** in-depth potentiometric and calorimetric investigation allowed to determine speciation models featured by simple ML,MLH i and ML(OH)species.A complete thermodynamic characterization of the systems is reported together with the definition of coordination mode by mass spectrometry *** the light of the speciation models,the possibility of using these ligands in arsenic removal techniques was assessed by determining the pL 0.5(the concentration of ligand able to remove the 50%of metal ion present in trace).All ligands show a good sequestering ability,in particular under the conditions of fresh water,following the trend NTA3P>NTA2P>NTAP.

关键词： Phosphonate ligands Arsenic Thermodynamic interaction parameters Sequestering ability