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Experimental tests for a liquid-liquid critical point in water

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Science China(Physics,Mechanics & Astronomy) 2020年第12期63卷 30-71页

作者： Domenico Mallamace Carmelo Corsaro Francesco Mallamace H.Eugene Stanley Department ChiBioFarAm(Industrial Chemistry) University of MessinaERIC and CASPE/INSTMMessina 98166Italy Dipartimento MIFT Universitàdi MessinaMessina 98166Italy Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridge MA 02139USA istituto dei sistemi complessi(ISC)-CNR Rome 00185Italy Center for Polymer Studies and Department of Physics Boston UniversityBoston MA 02215USA

Water is a fascinating *** composition is simple—one oxygen and two hydrogen atoms—but its chemistry and physics are extremely complex and exhibit 75 documented *** these anomalies and their molecular origin are not completely understood,we know that hydrogen bonds play key roles in all of the phases of ***,there is experimental evidence that the polymorphism of the ice structure extends into the liquid phase and is associated with a liquid-liquid coexistence *** is currently a topic of great interest in water research because there are indications that the end point of the coexistence line corresponds to a second critical point inside the supercooled liquid *** examine the recent progress in understanding water anomalies and the liquid-liquid phase transition hypothesis,including the results of recent experimental work and molecular simulations of both bulk and confined *** examine experimental results that test whether the behavior of liquid water is consistent with the"liquid polymorphism"hypothesis that liquid water can exist in two distinct phases of differing *** also examine recent research on the anomalies of nanoconfined water and,in particular,on water in biological *** find that the concept of liquid polymorphism can also describe the properties of other liquids that have two characteristic length scales.

关键词： hydrophobic-hydrophilic interactions water systems thermal properties

NMR investigation of degradation processes of ancient and modern paper at different hydration levels

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Frontiers of physics 2018年第1期13卷 41-50页

作者： Domenico Mallamace Sebastiano Vasi Mauro Missori Francesco Mallamace Carmelo Corsaro Consorzio interuniversitario per lo sviluppo dei sistemi a Grande Interfase - CSGI Via della Lastruccia 3 50019 Sesto Fiorentino Firenze Italy Dipartimento MIFT Sezione di Fisica Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy istituto dei sistemi complessi Consiglio Nazionale delle Ricerche Unit Sapienza Piazzale Aldo Moro 5 00185 Roma Italy CNR-IPCF Messina Istituto per i Processi Chimico-Fisici Viale F. Stagno D'Alcontres 37 98158 Messina Italy Center for Polymer Studies and Department of Physics Boston University Boston MA 02215 USA

The degradation process of cellulose-made materials was investigated by means of nuclear magnetic resonance （NMR） spectroscopy, with particular emphasis on the role of water and on the hydration mechanism of cellulose fibrils. To accomplish this, the structure and dynamics of water within ancient and modern samples with different aging histories were investigated. The results mainly indicated that hydrolytic and oxidative reactions provoked the formation of acidic by-products. Furthermore, degradation processes were enhanced by higher amounts of water giving a progressive consumption of the amorphous regions of the cellulose. We propose NMR experiments as a benchmark for character- ization of the degradation state of paper, as well as for investigating the effectiveness of restoration treatments.

关键词： ancient paper degradation NMR hydration solvent dynamics

The onset of the tetrabonded structure in liquid water

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 51-59页

作者： Carla Andreani Carmelo Corsaro Domenico Mallamace Giovanni Romanelli Roberto Senesi Francesco Mallamace Dipartimento di Fisica and NAST Center Universita degli Studi di Roma Tor VergataRome 00133Italy CNR-IPCF Istituto peri Processi Chimico-Fisici del CNR di MessinaMessina 98158Italy Dipartimento MIFT Universita di MessinaMessina 98166Italy ISIS Facility Rutherford Appleton LaboratoryChiltonDidcotOxfordshire OX11 0QXUK istituto dei sistemi complessi(ISC)-CNR Rome 00185Italy Center for Polymer Studies and Department of Physics Boston UniversityBoston 02215USA

Water properties are dominated by the hydrogen bond interaction that gives rise in the stable liquid phase to the formation of a dynamical *** latter drives the water thermodynamics and is at the origin of its well known *** HB structural geometry and its changes remain uncertain and still are challenging research subjects.A key question is the role and effects of the HB tetrahedral structure on the local arrangement of neighboring molecules in *** the hydrogen dynamics in bulk water is studied through the combined use of Neutron Compton Scattering and NMR *** are discussed in the framework of previous studies performed in a wide temperature range,in the liquid,solid,and amorphous *** the first time this combined studies provide an experimental evidence of the onset of the water tetrahedral network at T^315 K,originally proposed in previous studies of transport coefficients and thermodynamical data;below this temperature the local order in water changes and the lifetime of local hydrogen bond network becomes long enough to gradually develop the characteristic tetrahedral network of water.

关键词： water neutron compton scattering NMR

Biosensing with free space whispering gallery mode microlasers

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Photonics Research 2023年第5期11卷 732-741页

作者： ANGELA CAPOCEFALO SILVIA GENTILINI LORENZO BAROLO PAOLA BAIOCCO CLAUDIO CONTI NEDA GHOFRANIHA istituto dei sistemi complessi-CNR UOS UniversitàLa SapienzaI-00185 RomeItaly Dipartimento di Scienze Biochimiche A.Rossi Fanelli UniversitàLa SapienzaI-00185 RomeItaly Dipartimento di Fisica UniversitàLa SapienzaI-00185 RomeItaly

Highly accurate biosensors for few or single molecule detection play a central role in numerous key fields,such as healthcare and environmental *** the last decade,laser biosensors have been investigated as proofs of concept,and several technologies have been *** here propose a demonstration of polymeric whispering gallery microlasers as biosensors for detecting small amounts of proteins,down to 400 *** have the advantage of working in free space without any need for waveguiding for input excitation or output signal *** photonic microsensors can be easily patterned on microscope slides and operate in air and *** estimate the limit of detection up to 148 nm/RIU for three different protein *** addition,the sensing ability of passive spherical resonators in the presence of dielectric nanoparticles that mimic proteins is described by massive ab initio numerical simulations.

关键词： passive mode excitation

Air-core fiber distribution of hybrid vector vortex-polarization entangled states

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Advanced Photonics 2019年第4期1卷 42-50页

作者： Daniele Cozzolino Emanuele Polino Mauro Valeri Gonzalo Carvacho Davide Bacco NicoloSpagnolo Leif K.Oxenløwe Fabio Sciarrino Technical University of Denmark CoE SPOCDepartment of Photonics EngineeringLyngbyDenmark Sapienza Universitàdi Roma Dipartimento di FisicaRomaItaly Consiglio Nazionale delle Ricerche Istituto dei Sistemi ComplessiRomaItaly

Entanglement distribution between distant parties is one of the most important and challenging tasks in quantum *** of photonic entangled states using optical fiber links is a fundamental building block toward quantum *** the different degrees of freedom,orbital angular momentum(OAM)is one of the most promising due to its natural capability to encode high dimensional quantum *** experimentally demonstrate fiber distribution of hybrid polarization-vector vortex entangled photon *** this end,we exploit a recently developed air-core fiber that supports OAM *** fidelity distribution of the entangled states is demonstrated by performing quantum state tomography in the polarization-OAM Hilbert space after fiber propagation and by violations of Bell inequalities and multipartite entanglement *** results open new scenarios for quantum applications where correlated complex states can be transmitted by exploiting the vectorial nature of light.

关键词： orbital angular momentum quantum communication structured light multimode fiber multipartite entanglement

Global optimization of protein-peptide docking by a filling function method

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Open Journal of Applied Sciences 2012年第4期2卷 26-29页

作者： Francesco Lampariello Giampaolo Liuzzi istituto di Analisi dei sistemi ed Informatica (IASI) CNR Rome Italy

Molecular docking programs play a crucial role in drug design and development. In recent years, much attention has been devoted to the protein-peptide docking problem in which docking of a flexible peptide with a known protein is sought. In this work we present a new docking algorithm which is based on the use of a filling function method for continuos constrained global optimization. Indeed, the protein-peptide docking position is sought by minimizing the conformational potential energy subject to constraints necessary to maintain the primary sequence of the given peptide. The resulting global optimization problem is difficult mainly for two reasons. First, the problem is large scale in constrained global optimization;second, the energy function is multivariate non-convex so that it has many local minima. The method is based on the device of modifying the original objective function once a local minimum has been attained by adding to it a filling term. This allows the overall algorithm to escape from local minima thus, ultimately, giving the algorithm ability to explore large regions in the peptide conformational space. We present numerical results on a set of benchmark docking pairs and comparison with the well-known software package for molecular docking PacthDock.

关键词： Protein-peptide docking potential reduction continuous global optimization

Algorithms to Compute the Largest Invariant Set Contained in an Algebraic Set for Continuous-Time and Discrete-Time Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 57-69页

作者： Laura Menini Corrado Possieri Antonio Tornambè Dipartimento di Ingegneria Industriale Universitàdi Roma Tor VergataRoma 00133Italy istituto di Analisi dei sistemi ed Informatica“A.Ruberti ”Consiglio Nazionale delle Ricerche(IASI-CNR)Roma 00185Italy Dipartimento di Ingegneria Civile e Ingegneria Informatica Universitàdi Roma Tor VergataRoma 00133Italy

In this paper, some computational tools are proposed to determine the largest invariant set, with respect to either a continuous-time or a discrete-time system, that is contained in an algebraic set. In particular, it is shown that if the vector field governing the dynamics of the system is polynomial and the considered analytic set is a variety, then algorithms from algebraic geometry can be used to solve the considered problem. Examples of applications of the method(spanning from the characterization of the stability to the computation of the zero dynamics) are given all throughout the paper.

关键词： Asymptotic stability discrete-time systems invariance nonlinear systems

Coulomb Friction Driving Brownian Motors

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Communications in Theoretical Physics 2014年第10期61卷 505-513页

作者： Alessandro Manacorda Andrea Puglisi Alessandro Sarracino Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly istituto dei sistemi complessi - CNR and Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly Kavli Institute for Theoretical Physics China the Chinese Academy of Sciences Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600case courrier 121Université Paris 64Place Jussieu75255 Paris CedexFrance

We review a family of models recently introduced to describe Brownian motors under the influence of Coulomb friction, or more general non-linear friction laws. It is known that, if the heat bath is modeled as the usual Langevin equation(linear viscosity plus white noise), additional non-linear friction forces are not sufficient to break detailed balance, i.e. cannot produce a motor effect. We discuss two possibile mechanisms to elude this problem. A first possibility, exploited in several models inspired to recent experiments, is to replace the heat bath's white noise by a "collisional noise", that is the effect of random collisions with an external equilibrium gas of particles. A second possibility is enlarging the phase space, e.g. by adding an external potential which couples velocity to position, as in a Klein–Kramers equation. In both cases, non-linear friction becomes sufficient to achieve a non-equilibrium steady state and, in the presence of an even small spatial asymmetry, a motor effect is produced.

关键词： Brownian motors ratchet effect Coulomb friction

Quantitative imaging of the complexity in liquid bubbles’evolution reveals the dynamics of film retraction

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Light(Science & Applications) 2019年第1期8卷 1021-1032页

作者： Biagio Mandracchia Zhe Wang Vincenzo Ferraro Massimiliano Maria Villone Ernesto Di Maio Pier Luca Maffettone Pietro Ferraro CNR-ISASI Istituto di Scienze Applicate e Sistemi Intelligenti“E.Caianiello”del CNRVia Campi Flegrei 3480078 PozzuoliNapoliItaly College of Applied Sciences Beijing University of Technology100124 BeijingChina Dipartimento di Ingegneria Chimica dei Materiali e della Produzione IndustrialeUniversita di Napoli FedericoⅡPiazzale Tecchio 8080125 NapoliItaly

The dynamics and stability of thin liquid films have fascinated scientists over many *** film flows are central to numerous areas of engineering,geophysics,and biophysics and occur over a wide range of lengths,velocities,and liquid property *** spite of many significant developments in this area,we still lack appropriate quantitative experimental tools with the spatial and temporal resolution necessary for a comprehensive study of film *** propose tackling this problem with a holographic technique that combines quantitative phase imaging with a custom setup designed to form and manipulate *** results,gathered on a model aqueous polymeric solution,provide unparalleled insight into bubble dynamics through the combination of a full-field thickness estimation,threedimensional imaging,and a fast acquisition *** unprecedented level of detail offered by the proposed methodology will promote a deeper understanding of the underlying physics of thin film dynamics.

关键词： film dynamics liquid