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Absolute band alignment at semiconductor-water interfaces using explicit and implicit descriptions for liquid water

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npj Computational Materials 2019年第1期5卷 256-261页

作者： nicola. g.hörmann Zhendong guo Francesco Ambrosio Oliviero Andreussi Alfredo Pasquarello nicola.Marzari Theory and Simulation of Materials(ThEOS) and National Centre for Computational Design and Discovery of Novel Materials(MARVEL)École Polytechnique Fédérale de Lausanne1015 LausanneSwitzerland Chair of Theoretical Chemistry Technische Universität München85748 GarchingGermany Chaire de Simulationàl’Echelle Atomique(CSEA) École Polytechnique Fédérale de Lausanne1015 LausanneSwitzerland Department of Physics University of North TexasDentonTX 76207USA

Quantum mechanical simulations that include the effects of the liquid environment are highly relevant for the characterization of solid-liquid interfaces,which is crucial for the design of a wide range of *** this work we present a rigorous and systematic study of the band alignment of semiconductors in aqueous solutions by contrasting a range of hybrid explicit/implicit models against explicit atomistic simulations based on density-functional *** find that consistent results are obtained provided that the first solvation shell is treated ***,the first molecular layer of explicit water is only relevant for the pristine surfaces without dissociatively adsorbed water,hinting at the importance of saturating the surface with quantum mechanical *** referencing the averaged electrostatic potentials of explicit and implicit water against vacuum,we provide absolute alignments,finding maximal differences of only~0.1–0.2 ***,the implicit reference potential is shown to exhibit an intrinsic offset of−0.33 V with respect to vacuum,which is traced back to the absence of an explicit water surface in the implicit *** results pave the way for accurate simulations of solid-liquid interfaces using minimalistic explicit/implicit models.

关键词： theory implicit explicit

Empirical assessment of the role of the Sun in climate change using balanced multi-proxy solar records

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geoscience Frontiers 2023年第6期14卷 191-209页

作者： nicola.Scafetta Department of Earth Sciences Environment and GeoresourcesUniversity of Naples Federico IIComplesso Universitario di Monte S.Angelovia Cinthia21Naples 80126Italy

The role of the Sun in climate change is hotly *** studies suggest its impact is significant,while others suggest it is *** Intergovernmental Panel on Climate Change(IPCC)supports the latter view and suggests that nearly 100%of the observed surface warming from 1850–1900 to 2020 is due to anthropogenic ***,the IPCC’s conclusions are based solely on computer simulations made with global climate models(gCMs)forced with a total solar irradiance(TSI)record showing a low multi-decadal and secular *** same models also assume that the Sun affects the climate system only through radiative forcing–such as TSI–even though the climate could also be affected by other solar *** this paper I propose three“balanced”multi-proxy models of total solar activity(TSA)that consider all main solar proxies proposed in scientific *** optimal signature on global and sea surface temperature records is assessed together with those produced by the anthropogenic and volcanic radiative forcing functions adopted by the CMIP6 *** is done by using a basic energy balance model calibrated with a differential multi-linear regression methodology,which allows the climate system to respond to the solar input differently than to radiative forcings alone,and to evaluate the climate’s characteristic time-response as *** proposed methodology reproduces the results of the CMIP6 gCMs when their original forcing functions are applied under similar physical conditions,indicating that,in such a scenario,the likely range of the equilibrium climate sensitivity(ECS)could be 1.4℃to 2.8℃,with a mean of 2.1℃(using the hadCRUT5 temperature record),which is compatible with the low-ECS CMIP6 gCM ***,if the proposed solar records are used as TSA proxies and the climatic sensitivity to them is allowed to differ from the climatic sensitivity to radiative forcings,a much greater solar impact on climate change is found,along with a significant

关键词： Solar activity changes Solar variability climatic impact global climate change and modeling Equilibrium climate sensitivity

Impacts and risks of“realistic”global warming projections for the 21st century

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geoscience Frontiers 2024年第2期15卷 392-416页

作者： nicola.Scafetta Department of Earth Sciences Environment and GeoresourcesUniversity of Naples Federico IIComplesso Universitario di Monte S.AngeloVia Vicinale Cupa Cintia2180126 NaplesNAItaly

The IPCC AR6 assessment of the impacts and risks associated with projected climate changes for the 21st century is both alarming and *** to computer projections,global surface temperature may warm from 1.3℃to 8.0℃by 2100,depending on the global climate model(gCM)and the shared socioeconomic pathway(SSP)scenario used for the *** climate-change hazards are estimated to be high and very high if the global surface temperature rises,respectively,more than 2.0℃and 3.0℃above pre-industrial *** studies,however,showed that a substantial number of CMIP6 gCMs run“too hot”because they appear to be too sensitive to radiative forcing,and that the high/extreme emission scenarios SSP3-7.0 and SSP5-8.5 are to be rejected because judged to be unlikely and highly unlikely,***,the IPCC AR6 mostly focused on such alarmistic scenarios for risk *** paper examines the impacts and risks of“realistic”climate change projections for the 21st century generated by assessing the theoretical models and integrating them with the existing empirical knowledge on global warming and the various natural cycles of climate change that have been recorded by a variety of scientists and *** is achieved by combining the SSP2-4.5 scenario(which is the most likely SSP according to the current policies reported by the International Energy Agency)and empirically optimized climate *** to recent research,the gCM macro-ensemble that best hindcast the global surface warming observed from 1980 to 1990 to 2012–2022 should be made up of models that are characterized by a low equilibrium climate sensitivity(ECS)(1.5℃he IPCC AR6 likely and very likely ECS ranges at 2.5–4.0℃and 2.0–5.0℃,respectively.I show that the low-ECS macro-gCM with the SSP2-4.5 scenario projects a global surface temperature warming of 1.68–3.09℃by 2080–2100 instead of 1.98–3.82℃obtained with the gCMs with ECS in the 2.5–4.0℃range.h

关键词： Climate change Climate models Shared socioeconomic pathways 21st-century climate projections Impacts and risks assessment

Effect of template shape on metal nanoimprinting:a dislocation dynamics study

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 722-726页

作者： Lucia nicola Department of Materials Science and Engineering Delft University of Technology

Dislocation dynamics simulations are performed to investigate the effect of template shape on the nanoimprinting of metal layers. To this end, metal thin films are imprinted by a rigid template made of an array of equispaced indenters of various shapes, i.e., rectangular, wedge, and circular. The geometry of the indenters is chosen such that the contact area is approximately the same at the final imprinting depth. Results show that, for all template shapes, the final patterns strongly depend on the dislocation activity, and that each imprint differs from the neighboring ones. Large material pile ups appear between the imprints, such that polishing of the metal layer is suggested for application of the patterns in electronics. Rectangular indenters require the lowest imprinting force and achieve the deepest retained imprints.

关键词： Nanoimprinting Dislocation dynamics Simulations

Transport coefficients of a massive pion gas

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Chinese Physics C 2010年第9期34卷 1453-1455页

作者： D.Fernández-Fraile A.gómez nicola Institut für Theoretische Physik Johann Wolfgang Goethe-Universitt Departamento de Física Teórica II Universidad Complutense

We review our main results concerning the transport coefficients of a light meson gas,in particular we focus on the case of a massive pion *** order results according to the chiral power-counting are presented for the DC electrical conductivity,thermal conductivity,shear viscosity,and bulk *** also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD,as well as the relation between unitarity and a minimum of the quotient η/s near the phase transition.

关键词： transport coefficients heavy-ion collisions Chiral Perturbation Theory

Production of metallic iron nanoparticles in a baffled stirred tank reactor: Optimization via computational fluid dynamics simulation

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Particuology 2020年第5期18卷 83-96页

作者： giorgio Vilardi nicola.Verdone Sapienza University of Rome Department of Chemical Engineering Materials EnvironmentVia Eudossiana 1800184RomeItaly

The aim of this work is to optimize iron nanoparticle production in stirred tank reactors equipped with two classical impellers:Rushton and four-pitched blade turbines,which are largely used in batch industrial synthesis and efficient *** main operative parameters of nanoparticle synthesis are the precursor initial concentration,reducing agent/precursor molar ratio,impeller-tank clearance,and impeller rotational *** parameters were varied during the synthesis to find the optimal operating values based on the Fe(0)(%)production,zeta potential,particle size distribution,and powder X-ray diffraction pattern *** found that the optimal operating conditions for nanoparticle production were an impeller velocity of 1500 rpm,initial iron precursor concentration of 20 mM,molar ratio of reducing agent to iron precursor of 3 mol/mol,and impeller clearance of 0.25 and 0.4 times the vessel diameter for Rushton and four-pitched blade impellers,*** these conditions achieved a total conversion of 0.94-0.98 and yielded a product with a unimodal size distribution and average diameters in the range 30-50 *** computational fluid dynamics results agreed with the expectations,and the obtained mixing Damkohler numbers show that the process is mixed controlled.

关键词： Nano zero-valent iron Computational fluid dynamics Turbulence Micromixing Leng.h scale

Prospective associations between joint categories of physical activity and insomnia symptoms with onset of poor mental health in a population-based cohort

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Journal of Sport and health Science 2023年第3期12卷 295-303页

作者： Mitch J Duncan Elizabeth g.holliday nicola.W Burton Nicholas glozier Stina Oftedal School of Medicine and Public health College of HealthMedicineand WellbeingThe University of NewcastleCallaghanNSW 2308Australia Priority Research Centre for Physical Activity and Nutrition The University of NewcastleCallaghanNSW 2308Australia School of Applied Psychology Griffith UniversityBrisbaneQLD 4122Australia Menzies health Institute Queensland Griffith UniversityBrisbaneQLD 4122Australia Brain and Mind Centre Central Clinical SchoolThe University of SydneyNSW 2050Australia

Background:Physical inactivity and insomnia symptoms are independently associated with increased risk of depression and anxiety;however,few studies jointly examine these risk *** study aimed to prospectively examine the joint association of physical activity(PA)and insomnia symptoms with onset of poor mental health in ***:Participants from the 2013 to 2018 annnual waves of the household Income and Labour Dynamics in Australia panel study who had good mental health(Mental health Inventory-5>54)in 2013,and who completed at least 1 follow-up survey(2014-2018),were included(n=10,977).Poor mental health(Mental health Inventory-5≤54)was assessed ***(2013)PA was classified as high/moderate/low,and insomnia symptoms(i.e.,trouble sleeping)were classified as no insomnia symptoms/insomnia symptoms,with 6 mutually exclusive PAinsomnia symptom groups *** of PA-insomnia symptom groups with onset of poor mental health were examined using discrete-time proportional-hazards logit-hazard ***:There were 2322 new cases of poor mental health(21.2%).Relative to the high PA/no insomnia symptoms group,there were higher odds(odds ratio and 95%confidence interval(95%CI))of poor mental health among the high PA/insomnia symptoms(OR=1.87,95%CI:1.57-2.23),moderate PA/insomnia symptoms(OR=1.93,95%CI:1.61-2.31),low PA/insomnia symptoms(OR=2.33,95%CI:1.96-2.78),and low PA/no insomnia symptoms(OR=1.14,95%CI:1.01-1.29)*** level of PA combined with insomnia symptoms was associated with increased odds of poor mental health,with the odds increasing as PA ***:The se findings highlight the potential benefit of interventions targeting both PA and insomnia symptoms for promoting mental health.

关键词： Depression Physical activity Sleep quality

Water and lysozyme： Some results from the bending and stretching vibrational modes

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Frontiers of physics 2015年第5期10卷 27-34页

作者： FrancescoMallamace Carmelo Corsaro Domenico Mallamace Cirino Vasi nicola.Cicero h. Eugene Stanley Dipartimento di Fisica e Scienze della Terra Universita di Messina 1-98166 Messina Italy Department of Nuclear Science and Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA Center for Polymer Studies and Department of Physics Boston University Boston MA 02215 USA Consiglio Nazionale delle Ricerche-IPCF Messina 1-98166 Messina Italy Dipartimento di Scienze dell'Ambiente della Sicurezza del Territorio degli Alimenti e della Salute Universita di Messina Viale F. Stagno d'Alcontres 31 98166 Messina Italy

The dynamic or glass transition in biomolecules is important to their functioning. Also essential is the transition between the protein native state and the unfolding process. To better understand these transitions, we use Fourier transform infrared spectroscopy to study the vibrational bending and stretching modes of hydrated lysozymes across a wide temperature range. We find that these transitions are triggered by the strong.hydrogen bond coupling between the protein and hydration water. More precisely, we demonstrate that in both cases the water properties dominate the evolution of the system. We find that two characteristic temperatures are relevant： in the supercooled regime of confined water, the fragile-to-strong dynamic transition occurs at TL, and in the stable liquid phase, T＊ 315 ± 5 K characterizes the behavior of both isothermal compressibility KT（T, P） and the coefficient of thermal expansion ap（T, P）.

关键词： protein unfolding hydration water infrared spectroscopy

Screw dislocation structure and mobility in body centered cubic Fe predicted by a gaussian Approximation Potential

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npj Computational Materials 2018年第1期4卷 90-96页

作者： Francesco Maresca Daniele Dragoni gábor Csányi nicola.Marzari William A.Curtin Laboratory for Multiscale Mechanics Modeling(LAMMM) Institute of Mechanical EngineeringÉcole Polytechnique Fédérale de LausanneLausanne CH-1015Switzerland Theory and Simulation of Materials(ThEOS) and National Centre for Computational Design and Discovery of Novel Materials(NCCR MARVEL)École Polytechnique Fédérale de LausanneLausanne CH-1015Switzerland Dipartimento di Scienza dei Materiali Universitàdi Milano-BicoccaVia R.Cozzi 55Milan I-20125Italy Department of Engineering University of CambridgeTrumpington StreetCambridge CB21PZUK

The plastic flow behavior of bcc transition metals up to moderate temperatures is dominated by the thermally activated glide of screw dislocations,which in turn is determined by the atomic-scale screw dislocation core structure and the associated kink-pair nucleation mechanism for *** complex plasticity phenomena requires the simulation of many atoms and interacting dislocations and *** sizes are beyond the scope of first-principles methods and thus require empirical interatomic *** for the technological important case of bcc Fe,existing empirical interatomic potentials yield spurious ***,the structure and motion of the screw dislocations in Fe are studied using a new gaussian Approximation Potential(gAP)for bcc Fe,which has been shown to reproduce the potential energy surface predicted by density-functional theory(DFT)and many associated *** Fe gAP predicts a compact,non-degenerate core structure,a single-hump Peierls potential,and glide on{110},consistent with DFT *** thermally activated motion at finite temperatures occurs by the expected kink-pair nucleation and propagation *** stress-dependent enthalpy barrier for screw motion,computed using the nudgedelastic-band method,follows closely a form predicted by standard theories with a zero-stress barrier of~1 eV,close to the experimental value of 0.84 eV,and a Peierls stress of~2 gPa consistent with DFT predictions of the Peierls potential.

关键词： structure dislocation cubic