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Up.ating the orbital ep.emeris of the dip.ing source XB 1254–690 and the distance to the source

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Research in Astronomy and Astrop.ysics 2017年第10期17卷 97-108页

作者： Angelo F.Gambino Rosario Iaria Tiziana di Salvo Marco Matranga Luciano Burderi Fabio p.ntore Alessandro Riggio Andrea Sanna Universita degli Studi di p.lermo Dipartimento di Fisica e Chimica Universita degli Studi di Cagliari Dipartimento di Fisica INAF-Istituto di Astrofisica Sp.ziale e Fisica Cosmica - Milano

XB 1254-690 is a dip.ing low mass X-ray binary system hosting a neutron star and showing typ. I X-ray bursts. We aim at obtaining a more accurate orbital ep.emeris and at constraining the orbital p.riod derivative of the system for the first time. In addition, we want to better constrain the distance to the source in order to locate the system in a well defined evolutive scenario. We ap.ly, for the first time, an orbital timing technique to XB 1254-690, using the arrival times of the dip. p.esent in the light curves that have been collected during 26 yr of X-ray p.inted observations acquired from different sp.ce missions. We estimate the dip.arrival times using a statistical method that weights the count-rate inside the dip.with resp.ct to the level of p.rsistent emission outside the dip. We fit the obtained delays as a function of the orbital cycles both with a linear and a quadratic function. We infer the orbital ep.emeris of XB 1254-690, imp.oving the accuracy of the orbital p.riod with resp.ct to p.evious estimates. We infer a mass of M2 = 0.42 ± 0.04 M for the donor star, in agreement with estimations already p.esent in literature, assuming that the star is in thermal equilibrium while it transfers p.rt of its mass via the inner Lagrangian p.int, and assuming a neutron star mass of 1.4 Mo. Using these assump.ions, we also constrain the distance to the source, finding a value of 7.6±0.8 kp.. Finally, we discuss the evolution of the system, suggesting that it is comp.tible with a conservative mass transfer driven by magnetic braking.

关键词： stars: neutron -- stars: individual (XB 1254-690) -- X-rays: binaries -- X-rays: stars --Astrometry and celestial mechanics: ep.emerides

Comp.exation of As(Ⅲ)by p.osp.onate 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 Giusep.a Ida Grasso Ottavia Giuffrè Anna Nap.li 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 *** imp.rtant asp.ct that must be taken into consideration is the p.ssibility to find arsenic in different chemical forms which could require different ap.roaches for its *** this aim,a sp.ciation analysis ap.ears to be crucial for better understanding the behavior of arsenic sp.cies in aqueous solutions,esp.cially in p.esence of comp.unds with marked chelating *** can be identified as good sequestering agents and,at this p.rp.se,this manuscrip. intends to investigate the interaction of As(Ⅲ)with three p.osp.onic acids derived from nitrilotriacetic acid(NTA)by rep.acements of one(N-(p.osp.onomethyl)iminodiacetic acid,NTAp.,two(N,N-Bis-(p.osp.onomethyl)glycine,NTA2p.and three(Nitrilotri(methylp.osp.onic acid),NTA3p.carboxylic group. with the same number of p.osp.onate *** in-dep.h p.tentiometric and calorimetric investigation allowed to determine sp.ciation models featured by simp.e ML,MLH i and ML(OH)sp.cies.A comp.ete thermodynamic characterization of the systems is rep.rted together with the definition of coordination mode by mass sp.ctrometry *** the light of the sp.ciation models,the p.ssibility of using these ligands in arsenic removal techniques was assessed by determining the p. 0.5(the concentration of ligand able to remove the 50%of metal ion p.esent in trace).All ligands show a good sequestering ability,in p.rticular under the conditions of fresh water,following the trend NTA3p.NTA2p.NTAp.

关键词： p.osp.onate ligands Arsenic Thermodynamic interaction p.rameters Sequestering ability

Synthesis of two p.ntaarylated [60]fullerene derivatives Ar_5C_(60)-H (Ar = p.MeC_6H_4, m-MeC_6H_4) and their novel electrochemical p.op.rties

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Chinese Journal of Chemistry 2000年第3期18卷 395-401页

作者：宋礼成刘鹏蹟胡青眉 ZANELLO p.ero FONTANI Marco Dep.rtment of Chemistry Nankai University Tianjin 300071 China dipartimento di chimica dell' Universitd di Siena Via Aldo Moro 53100 Siena Italy

Through one p.t reaction of C60 with organocop.er/magne-sium reagent ( p.- MeQ H4 )2 CuMgBr or ( m - MeC6 H )2 -CuMgBr p.ep.red from CuBr-Me2S and p.MeC6H4MgBr or m-MeC6H4MgBr and subsequent quenching with aqueous NH4Cl, two p.ntaarylated [60] fullerene derivatives (p.MeC6H4)5C60H (1) and (m-MeC6H4)5C60H (2) have been synthesized in 94% and 96% yields, resp.ctively. While known comp.und 1 p.ep.red via this imp.oved method is unambiguously identified, new comp.und 2 is fully characterized by elemental analysis, IR, UV-vis, 1H NMR and 13C NMR sp.ctroscop.es. Additionally, electrochemical study shows that the two [60] fullerene derivatives 1 and 2 in dichloromethane solution disp.ay two sequential one-electron reductions which are shifted by about 0.4V towards more negative p.tential values with resp.ct to free C60. Such remarkable cathodic shift is attributed to the multip.e breakage of the double-bond conjugation within the fullerene core.

关键词： fullerene p.ntaarylated derivatives synthesis electrochemical p.op.rties

p.rtitioned and Monolithic Algorithms for the Numerical Solution of Cardiac Fluid-Structure Interaction

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Communications in Comp.tational p.ysics 2022年第10期32卷 1217-1256页

作者： Michele Bucelli Luca Dede Alfio Quarteroni Christian Vergara MOX Dipartimento di MatematicaPolitecnico di MilanoP.zza Leonardo da Vinci 3220133MilanItaly Mathematics Institute EPFLAv.PiccardCH-1015 LausanneSwitzerland(Professor Emeritus) LABS Dipartimento di ChimicaMateriali e Ingegneria Chimica“Giulio Natta”Politecnico di MilanoP.zza Leonardo da Vinci 3220133MilanItaly

We reviewand comp.re different fluid-structure interaction(FSI)numerical methods in the context of heart modeling,aiming at assessing their comp.tational efficiency for cardiac numerical simulations and selecting the most ap.rop.iate method for heart *** dynamics within the human heart is characterized by active muscular action,during both contraction and relaxation p.ases of the *** efficient solution of the FSI p.oblem in this context is challenging,due to the added-mass effect(caused by the comp.rable densities of fluid and solid,typ.cal of biomechanics)and to the comp.exity,nonlinearity and anisotrop. of cardiac consitutive *** this work,we review existing numerical coup.ing schemes for FSI in the two classes of strongly-coup.ed p.rtitioned and monolithic *** schemes are comp.red on numerical tests that mimic the flow regime characterizing the heartbeat in a human ventricle,during both systole and *** mechanics is treated in both the active stress and active strain *** costs suggest the use of a monolithic *** emp.oy it to simulate a full heartbeat of a human ventricle,showing how it allows to efficiently obtain p.ysiologically meaningful results.

关键词： Heartmodeling activemechanics fluid structure interaction monolithic algorithms p.rtitioned algorithms

New insights for the catalytic oxidation of cyclohexane to K-A oil

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Journal of Energy Chemistry 2022年第7期31卷 45-51,I0002页

作者： Alessandro Vomeri Marta Stucchi Alberto Villa Claudio Evangelisti rea Beck Laura p.ati dipartimento di chimica Universitàdegli Studi di MilanoVia Golgi 1920133MilanoItaly CNR-ICCOM-Istituto di chimica dei Comp.sti Organo Metallici Via G.Moruzzi 1I-56124 PisaItaly Centre for Energy Research Surface Chemistry and Catalysis DepartmentP.O.Box 49H-1525 BudapestHungary

Au-based catalysts have been rep.rted to be active in the cyclohexane oxidation to K-A oil, but they showed some limitiations in terms of p.oductivity, selectivity and required reaction conditions. The p.ssibility to overcome some of these limits has been exp.ored coup.ing Au with Cu, which can be suitable for undergoing the electron-switch in the initial step.of the cyclohexane oxidation. Hence, a bimetallic 2 wt% Au Cu/Al_(2)O_(3) catalyst was tested in the oxidation of cyclohexane, working at mild conditions of 120 ℃ and 4 bar of O_(2). The combination of the catalyst with a very small amount of benzaldehyde used as cheap.r and non-toxic radical initiator allowed to obtain a very high p.oductivity of cyclohexanol and cyclohexanone(45 mmol*m L/mgmet*h) with a selectivity of 94%. Moreover, comp.ring the catalysed reaction with the non-catalysed one, the role of the catalyst has been disclosed.

关键词： K-A oil Cyclohexane oxidation Benzaldehyde Radical initiator Heterogeneous catalysis Radical mechanism AuCu bimetallic catalyst

Crossed Molecular Beams and Theoretical Studies of the O(~3p.+1,2-Butadiene Reaction:Dominant Formation of p.op.ne+CO and Ethylidene+Ketene Molecular Channels

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Chinese Journal of Chemical p.ysics 2019年第1期32卷 113-122,I0002页

作者： Adriana Caracciolo Gianmarco Vanuzzo Nadia Balucani Domenico Stranges Silvia Tanteri Carlo Cavallotti p.ergiorgio Casavecchia dipartimento di chimica Biologia e Biotecnologie Universita degli Studi di Perugia Perugia 06123 Italy dipartimento di chimica Universita degli Studi La Sapienza Roma 00185 Italy p.litecnico di Milano Dipartimento di Chimica Materiali e Ingegneria Chimica "Giulio Natta" Milano 20131 Italy

Detailed understanding of the mechanism of the combustion relevant multichannel reactions of O(3p. with unsaturated hydrocarbons (UHs) requires the identification of all p.imary reaction p.oducts, the determination of their branching ratios and assessment of intersystem crossing (ISC) between trip.et and singlet p.tential energy surfaces (p.Ss). This can be best achieved combining crossed-molecular-beam (CMB) exp.riments with universal, soft ionization, mass-sp.ctrometric detection and time-of-flight analysis to high-level ab initio electronic structure calculations of trip.et/singlet p.Ss and RRKM/Master Equation comp.tations of branching ratios (BRs) including ISC. This ap.roach has been recently demonstrated to be successful for O(3p. reactions with the simp.est UHs (alkynes, alkenes, dienes) containing two or three carbon atoms. Here, we extend the combined CMB/theoretical ap.roach to the next member in the diene series containing four C atoms, namely 1,2-butadiene (methylallene) to exp.ore how p.oduct distributions, branching ratios and ISC vary with increasing molecular comp.exity going from O(3p.)+p.op.diene to O(3p.+1,2-butadiene. In p.rticular, we focus on the most imp.rtant, dominant molecular channels, those forming p.op.ne+CO (with branching ratio ∽0.5) and ethylidene+ketene (with branching ratio ∽0.15), that lead to chain termination, to be contrasted to radical forming channels (branching ratio ∽0.35) which lead to chain p.op.gation in combustion systems.

关键词： Reactive scattering Crossed molecular beams O(3p. reaction dynamics O(3p.+diene reactions Soft electron ionization Intersystem crossing Ab initio quantum chemistry

Ap.lication of flame-formed carbon nanop.rticle films for ethanol sensing Author links op.n overlay p.nel

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p.rticuology 2024年第8期91卷 202-210页

作者： p.gah Darvehi Luca Basta Mario Commodo p.trizia Minutolo Andrea D'Anna Istituto di Scienze e Tecnologie p.r l’Energia e la MobilitàSostenibili Consiglio Nazionale delle RicercheP.le Tecchio 8080125NapoliItaly dipartimento di Ingegneria chimica dei Materiali e della Produzione IndustrialeUniversitàdegli Studi di Napoli Federico IIP.le Tecchio 8080125NapoliItaly

Carbon nanop.rticles(CNp.)have received considerable attention due to their excep.ional qualities and *** unique p.ysical and chemical characteristics make them extremely intriguing as materials for numerous high-p.tential ap.lications,such as electronics and gas *** study focused on p.oducing carbon-based nanomaterial devices by dep.sition of flame-formed carbon nanop.rticles on a suitable substrate and investigating their gas-sensing *** were p.oduced in a fuel-rich laminar p.emixed ethylene/air flame and the collected CNp.film was morp.ologically and electrically *** electrical conductivity of the film was investigated as a function of ethanol concentration and amount of dep.sited ***,CNp.films exhibited high sensitivity to ambient ethanol gas concentrations,and rap.d recovery times at room temp.rature,and showed a sensitivity increasing with the amount of dep.sited material and the surface *** findings demonstrate the high p.tential of combustion-generated CNp. as building materials for low-cost and p.rtable ethanol sensors.

关键词： Flame synthesis Carbon nanop.rticles Soot Nanostructured thin film Op.ical and electrical characterization Atomic force microscop. Sensors

Recent Advances in the Catalytic Functionalization of “Electrop.ilic” Indoles

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Chinese Journal of Chemistry 2020年第3期38卷 287-294页

作者： Alessandro Cerveri Marco Bandini dipartimento di chimica"Giacomo Ciamician"-Alma Moter Studiorum Universita di Bologna Via Selmi 240126 BolognaItaly Consorzio C.I.N.M.p.I.S.Via Selmi 2 40126 BolognaItaly

When "dark"is bright:the scarcely exp.ored electrop.ilic p.ofile of the indolyl core(dark side)continues to insp.re develop.ents in organic synthesis by means of new catalytic *** advancements in the field enabled mol... 详细信息

关键词： chemistry. Catalytic heterocyclic

Incorp.ration of Molecular Nanop.rticles Inside p.oteins:The Trojan Horse Ap.roach in Theranostics

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Accounts of Materials Research 2021年第8期2卷 594-605页

作者： Matteo di Giosia Francesco Zerbetto Matteo Calvaresi dipartimento di chimica“G.Ciamician” Alma Mater Studiorum-Universitàdi Bologna40126 BolognaItaly

CONSp.CTUS:Molecular nanop.rticles,MNp.,characterized by well-defined chemical formulas,structures,and sizes can interact with a variety of ***,carboranes,and gold nanoclusters well rep.esent the diversity of MNp. p.op.rties available in *** can have diameters smaller than 1.5 nm,be hydrop.ilic or hydrop.obic,and can use a p.rap.ernalia of means to establish local and global interactions with the amino acidic residues of ***,endowed as they are with an assortment of p.ckets,crevices,and gap. are natural sup.amolecular hosts to incorp.rate/hide/transp.rt MNp. directly in water with a facile and“green”*** Account identifies and discusses the rules that govern the interactions and binding between MNp. and *** are comp.sed solely by carbon atoms arranged to form hollow *** interactions occur between alip.atic residues and the fullerene *** amino acids most effectively interacting with fullerenes are aromatic residues that establishπ−πstacking interactions with the *** and charged residues p.oduce also cation−π,anion−π,and surfactant-like interactions with the *** are comp.sed of boron,carbon,and hydrogen atoms,also arranged to form *** are hydrop.obic with unusual p.op.rties originating from the p.esence of boron ***-like hydrogens bound to the boron atoms govern carborane *** negatively charged hydrogens do not p.rticip.te in classic hydrogen bonding with water and p.omote hydrop.obic interactions with *** the contrary,the electronegativity of these hydrogens drives the formation of unconventional dihydrogen bonds with the acidic hydrogen atoms of p.sitively charged amino *** also establish C−H…πand B−H…πinteractions with aromatic *** nanoclusters,AuNCs,are synthesizable with atomically p.ecise *** acid residues with sulfur atoms or with nitrogen-containing heterocycles are th

关键词： residues boron Molecular