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Flash flood sediment transport in a steep sand-bed ephemeral stream

International Journal of Sediment Research 2011年第2期26卷 193-209页

作者： Paolo BILLI dipartimento di Scienze della Terra Universita di Ferrara

This paper reports about flow and sediment transport measurements undertaken during the rainy season(July-August) 2008 on Gereb Oda,a steep,sand-bed ephemeral stream,draining the western margin of the Kobo structural basin in northern *** Oda streambed is dry for most of the year since it is subjected only to sporadic flash floods in response to individual,high intensity and spatially confined *** about hydraulic and sediment transport processes in steep sand-bed,ephemeral stream is very poor and,though only two flash floods occurred during the field campaign,the data gathered may contribute to improve our knowledge on these kind of *** numbers were calculated in order to verify the occurrence of supercritical flow conditions as postulated by a few authors from the analysis of sedimentary structures *** data are also compared to simple models to predict flow velocity and discharge since flow recording systems are seldom installed on ephemeral streams in remote areas and developing *** rivers are known for their very high suspended sediment transport,but very little bedload data exist for sand-bed,ephemeral *** variation of suspended sediment concentration with discharge is analysed and simple rating curves for both suspended and bed load transport are derived.A few equations to predict bedload are tested against Gereb Oda data and the relationship between en masse bedload transport processes as thin sand sheets and the development of horizontal lamination through the migration of leaf-shaped,sheet-like bedforms is ***,large boulders were observed to move at flow depths of the same order of magnitude of their size.A few functions to predict the threshold conditions for large particles entrainment are used to verify if and to what extent they match Gereb Oda field *** increased density of the water-sediment mixture,for the very high suspended sediment concentr

关键词： Ephemeral stream Bedload Suspended load Flash flood Ethiopia

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Measurement of vibration frequencies of ties in masonry arches by means of a robotic total station

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 489-500页

作者： Marco Gatti dipartimento di Ingegneria University of Ferraravia Saragat 144123 FerraraItaly

Measurement of the vibration frequencies of eight ties set in masonry arches of a church by means of a robotic total station is *** instrument made continuous recordings(up to ten per second)of the three-dimensional positions of a reflector situated at 1/2 or 1/4 of the length of the tie during vertical oscillation induced by an impulsive *** recording slips,vibration amplitudes(and their accuracy),hourly diagram and experimental spectra of vibrations,and the corresponding frequencies were *** results were verified by comparing them with the vibration frequencies and indirectly the tension and fixed support constraint calculated from accelerometric *** study provides interesting information on the accuracies of the reflector′s three-dimensional coordinates,but highlighted certain limits in the application of robotized total stations for measuring vibration frequencies of ties in masonry arches.

关键词： RTS frequency vibrations ties arches

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Skew Braces of Size p^(2)q I:Abelian Type

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Algebra Colloquium 2022年第2期29卷 297-320页

作者： E.Acri M.Bonatto IMAS-CONICET and Universidad de Buenos Aires Pabellon 1 Ciudad Universitaria1428Buenos AiresArgentina dipartimento di Matematica e Informatica Universita di FerraraItaly

This is the first part of a series of two *** this paper we enumerate and classify the left braces of size p^(2)q,where p and q are distinct prime numbers,by the classification of regular subgroups of the holomorph of... 详细信息

关键词： Yang-Baxter equation set-theoretical solution skew brace Hopf-Galois extension

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A new method of discriminating different types of post-Archean ophiolitic basalts and their tectonic significance using Th-Nb and Ce-Dy-Yb systematics

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Geoscience Frontiers 2015年第4期6卷 481-501页

作者： Emilio Saccani dipartimento di Fisica e Scienze della Terra Università di Ferrara

In this paper, a new discrimination diagram using absolute measures of Th and Nb is applied to postArchean ophiolites to best discriminate a large number of different ophiolitic basalts. This diagram was obtained using 〉2000 known ophiolitic basalts and was tested using -560 modern rocks from known tectonic settings. Ten different basaltic varieties from worldwide ophiolitic complexes have been examined. They include two basaltic types that have never been considered before, which are：（1） medium-Ti basalts （MTB） generated at nascent forearc settings; （2） a type of mid-ocean ridge basalts showing garnet signature （G-MORB） that characterizes Alpine-type （i,e., non volcanic） rifted margins and ocean-continent transition zones （OCTZ）. In the Th-Nb diagram, basalts generated in oceanic subductionunrelated settings, rifted margins, and OCTZ can be distinguished from subduction-related basalts with a misclassification rate 〈 1%. This diagram highlights the chemical variation of oceanic, rifted margin, and OCTZ basalts from depleted compositions to progressively more enriched compositions reflecting, in turn, the variance of source composition and degree of melting within the MORB-OIB array. It also highlights the chemical contributions of enriched （OIB-type） components to mantle sources. Enrichment of Th relative to Nb is particularly effective for highlighting crustal input via subduction or crustal contamination. Basalts formed at continental margin arcs and island arc with a complex polygenetic crust can be distinguished from those generated in intra-oceanic arcs in supra-subducrion zones （SSZ） with a misclassification rate 〈1%. Within the SSZ group, two sub-settings can be recognized with a misclassification rate 〈0.5%. They are：（1） SSZ influenced by chemical contribution from subduction- derived components （forearc and intra-arc sub-settings） characterized by island arc tholeiitic （IAT） and boninitic basalts; （2） SSZ with no contribution from subduction-derived comp

关键词： Basalts Ophiolite discrimination diagram Trace elements Plate tectonics

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EXTENDED FEYNMAN FORMULA FOR HARMONIC OSCILLATOR AND ITS APPLICATION

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Science China Mathematics 1991年第11期34卷 1346-1353页

作者：梁九卿郭本宏 G.MORANdi Institute of Theoretical Physics Shanxi University Taiyuan 030006 PRC Department of physics Shanxi University Taiyuan 030006 PRC dipartimento di Fisica CISM-GNSM and INFN. Universita di FerraraV. Paradiso 12 I-44100 Ferrara Italy

We report on a new derivation of the extended Feynman propagator for the harmonic oscil-lator at and beyond caustics using the explicit eigenfunction expansion for the *** is shown that the Maslov corrections beyond caustics are directly determined by the parityof the eigenfunctions. The phase correction and related effect of the propagator of a chargedparticle in constant magnetic field and in the presence of Chern-Simon backgraound gaugefield are studied.

关键词： harmonic oscillator Feynman formula.

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A model to explain the angular distribution of J/Ψ and Ψ(2S) decay into ■ and ■

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Chinese Physics C 2019年第2期43卷 31-36页

作者： M.Alekseev A.Amoroso R.Baldini Ferroli I.Balossino M.Bertani D.Bettoni F.Bianchi J.Chai G.Cibinetto F.Cossio F.De Mori M.Destefanis R.Farinelli L.Fava G.Felici I.Garzia M.Greco L.Lavezzi C.Leng M.Maggiora A.Mangoni S.Marcello G.Mezzadri S.Pacetti P.Patteri A.Rivetti M.Da Rocha Rolo M.Savrié S.Sosio S.Spataro L.Yan Università di Torino INFN Sezione di Torino INFN Laboratori Nazionali di Frascati INFN Sezione di ferrara Institute of High Energy Physics Università di ferrara Università del Piemonte Orientale Università di Perugia INFN Sezione di Perugia

BESⅢ data show a particular angular distribution for the decay of J/Ψ and Ψ(2 S) mesons into ■ and Σ~0Σ~0 hyperons: the angular distribution of the decay Ψ(2 S) →Σ~0Σ~0 exhibits an opposite trend with respect to the other three channels: J/Ψ→■, J/Ψ→Σ~0Σ~0 and Ψ(2 S) →■. We define a model to explain the origin of this phenomenon.

关键词： J/ψandψ(2S)hadronic decays effective Lagrangian model polarization parameters

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Determination of particulate polycyclic aromatic hydrocarbons in ambient air by gas chromatography-mass spectrometry after molecularly imprinted polymer extraction

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Journal of Environmental Sciences 2023年第2期124卷 644-654页

作者： Maria Chiara Pietrogrande Giorgia Demaria Mara Russo Department of Chemical Pharmaceutical and Agraricultural SciencesUniversity of FerraraVia Fossato di Mortara 17/1944121 FerraraItaly

A solid phase extraction procedure(SPE)is described for the quantitative analysis of polycyclic aromatic hydrocarbons(PAHs)in atmospheric particulate matter(PM),as ubiquitous environmental pollutants routinely measured in air qualitymonitoring.A SPE cartridge was used based on a molecular imprinted polymer(MIP-SPE)properly tailored for selective retention of PAHs with 4 and more benzene fused *** performance of the clean-up procedure was evaluated with the specific concern of selective purification towards saturated hydrocarbons,which are the PM components mostly interfering GC analysis of target *** optimized operative conditions,the MIP-SPE provided analyte recovery close to 95%for heavier PAHs,from benzo(α)pyrene to benzo(ghi)perylene,and close to 90%for four benzene rings PAHs,with good reproducibility(RSDs:2.5%-5.9%).Otherwise,C_(17)-C_(32) n-alkanes were nearly completely *** proposed method was critically compared with Solid Phase Micro Extraction(SPME)using a polyacrylate *** methods were successfully applied to the analysis of ambient PM2.5 samples collected at an urban polluted *** the two procedures,the MIP-SPE provided the highest recovery(R%≥93%)for PAHs with 5 and more benzene rings,but lower for lighter *** contrast,SPME showed a mean acceptable R%value(∼80%)for all the investigated PAHs,except for the heaviest PAHs in the most polluted samples(R%:110%-138%),suggesting an incomplete purification from the interfering n-hydrocarbons.

关键词： Polycyclic aromatic hydrocarbons Atmospheric particle matter Molecularly imprinted polymers-solid-phase extraction Solid phase micro extraction GC/MS analysis

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Emergency surgery in COVID-19 outbreak:Has anything changed?Single center experience

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World Journal of Clinical Cases 2020年第17期8卷 3691-3696页

作者： Francesco D'Urbano Nicolo Fabbri Margherita Koleva Radica Eleonora Rossin Paolo Carcoforo Department of Morphology Experimental Medicine and SurgerySection of General SurgeryUniversity of FerraraFerrara 44100Italy Unit of General Surgery Azienda UnitàSanitaria Locale di FerraraFerrara 44100Italy

BACKGROUND The current coronavirus disease 19(COVID-19)pandemic is changing the organization of health care and has had a direct impact on the management of surgical *** the General Surgery Department of Sant’Anna University Hospital in ferrara,Italy,surgical activities were progressively reduced during the peak of the COVID-19 outbreak in *** this period,only one operating room was available for elective cancer surgeries and another for emergency ***,the number of beds for surgical patients had to be reduced to provide beds and personnel for the new COVID-19 *** To compare 2 different period(from March 9 to April 92019 and from March 9 to April 92020),searching differences in terms of number and type of interventions in emergency surgery of a main University Hospital in ferrara,a city in Emilia Romagna region,North of *** This retrospective study was carried out at the General Surgery Department of Sant’Anna University Hospital in ferrara,*** examined the number of emergency surgeries performed and patient outcomes during the peak of the COVID-19 outbreak in Italy and subsequent total *** then drew a comparison with the number of surgeries performed and their outcomes during the same period in *** study examined all adult patients who underwent emergency surgery from March 9 to April 9,2019(n=46),and those who underwent surgery during the first month of the lockdown,from March 9 to April 9,2020(n=27).Analyses were adjusted for age,gender,American Society of Anesthesiologists classification scores and types of *** A total of 27 patients underwent emergency surgery at Sant’Anna University Hospital in ferrara during the first month of the *** represents a 41.3%reduction in the number of patients who were hospitalized and underwent emergency surgery compared to the same period in *** complication rate during the pandemic period was substantially higher than it was during the an

关键词： COVID-19 Emergency surgery Outbreak

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diet and nutrition against inflammatory bowel disease: Trick or treat(ment)?

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World Journal of Experimental Medicine 2022年第5期12卷 104-107页

作者： Salvatore Greco Beatrice Bonsi NicolòFabbri Department of Translational Medicine University of FerraraFerrara 44100Italy Department of Internal Medicine Azienda UnitàSanitaria Locale Di FerraraOspedale del DeltaAzienda UnitàSanitaria Locale di FerraraFerrara 44100Italy Unit of General Surgery Azienda UnitàSanitaria Locale di FerraraOspedale del DeltaAzienda UnitàSanitaria Locale di FerraraFerrara 44100Italy

Even if the relationships between nutrition and inflammatory bowel disease(IBD)remain underexplored,the current literature is providing,day by day,much more evidence on the effects of various diets in both prevention and treatment of such *** dietary habits,together with other environmental factors such as pollution,breastfeeding,smoke,and/or antibiotics,are among the theoretical pathogenetic causes of IBD,whose multifactorial aetiology has been already *** some of these risk factors are potentially reversible,some others cannot be avoided,and efficient treatments become necessary to prevent IBD spread or ***,the drugs currently available for treatment of such disease provide low-to-no effect against the symptoms,making the illnesses still strongly *** nutrition and specific diets will prove to effectively interrupt the course of IBD has still to be clarified and,in this sense,further research concerning the applications of such dietary interventions is still needed.

关键词： Crohn’s disease Ulcerative colitis Inflammatory bowel disease diet Nutrition Treatment

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Current collectors based on multiwalled carbon-nanotubes and fewlayer graphene for enhancing the conversion process in scalable lithium-sulfur battery

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Nano Research 2023年第6期16卷 8433-8447页

作者： Vittorio Marangon Edoardo Barcaro Luca Minnetti Wolfgang Brehm Francesco Bonaccorso Vittorio Pellegrini Jusef Hassoun Graphene Labs Istituto Italiano di TecnologiaGenoa 16163Italy Department of Chemical Pharmaceutical and Agricultural SciencesUniversity of FerraraFerrara 44121Italy Bedimensional S.p.A. Genoa 16163Italy National Interuniversity Consortium of Materials Science and Technology(INSTM) University of Ferrara Research UnitFerrara 44121Italy

We investigated herein the morphological,structural,and electrochemical features of electrodes using a sulfur(S)-super P carbon(SPC)composite(i.e.,S@SPC-73),and including few-layer graphene(FLG),multiwalled carbon nanotubes(MWCNTs),or a mixture of them within the current collector ***,we studied the effect of two different electron-conducting agents,that is,SPC and FLG,used in the slurry for the electrode *** supports have high structural crystallinity,while their morphologies are dependent on the type of material *** voltammetry(CV)shows a reversible and stable conversion reaction between Li and S with an activation process upon the first cycle leading to the decrease of cell *** activation process is verified by electrochemical impedance spectroscopy(EIS)with a decrease of the resistance after the first CV ***,CV at increasing scan rates indicates a Li+diffusion coefficient(D)ranging between 10^(−9) and 10^(−7) cm^(2)·s^(−1)in the various states of charge of the cell,and the highest D value for the electrodes using FLG as electron-conducting *** tests performed at constant current of C/5(1 C=1675 mA·g_(s)^(−1))show high initial specific capacity values,which decrease during the initial cycles due to a partial loss of the active material,and subsequently increase due to the activation *** the electrodes show a Coulombic efficiency higher than 97%upon the initial cycles,and a retention strongly dependent on the electrode ***,this study suggests a careful control of the electrode in terms of current collector design and slurry composition to achieve good electrode morphology,mechanical stability,and promising electrochemical performance in practical Li-S cells.

关键词： lithium-sulfur battery current collector few-layer graphene carbon nanotubes scalability sulfur loading

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