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In the commented paper, there are some questionable data which should be explained or corrected by the Authors, Thangamani et al. In this comment, I have tried to pinpoint incorrect data or inconsistencies and to verify the correctness of the data presented in the crystallographic part of the paper.

Multiple twinned structures are common in low-dimensional materials. They are intrinsically strained due to the geometrical constraint imposed by the non-crystallographic fivefold symmetry. In this study, the strain distributions in sub-10 nm fivefold twins of gold have been analyzed by combining aberration-corrected transmission electron microscopy and first-principles calculations. Bending of atomic planes has been measured by both experiments and calculations, and its contribution to the filling of the angular gap was shown to be size-dependent.

Utilization of biomass waste and solid industrial waste, one of the basic solutions of green economy, has become an important topic in both chemical and materials science. Individual bio-carbon, magnetic oxides, and their composites have been used in making microwave absorbers. Here, by utilizing coffee waste bio-carbon and industrial waste MnFe2O4 particles, an efficient microwave absorber has been realized based on their composites. The microwave absorption performance as well as the magnetization of as-synthesized composites can be tuned by adjusting the particle size of MnFe2O4. The minimum reflection loss (RLmini) can be enhanced around 5 times from -7.7 dB to -38.80 dB at 9.8 GHz when mean particle size of MnFe2O4 in the composites is reduced from 9.7 down to 0.9 μm. Meanwhile, a wide effective absorption bandwidth (7.8–11.4 GHz) is achieved in this bio-industrial-waste composite. Such enhancement is explained from viewpoint of appropriate impedance matching as well as the synergetic effect between the bio-carbon and the MnFe2O4. Our work provides a route for the utilization of bio-carbon waste and industrial magnetic waste in the field of microwave absorption.

The structure–performance relationship is a critical fundamental issue in heterogeneous catalysis, and the size-dependent structure sensitivity of catalytic reactions has long been researched in ca...

In this study we compare long-term Doppler and Raman lidar observations against a full month of large eddy simulations of continental shallow cumulus clouds. The goal is to evaluate if the simulations can reproduce the mean observed vertical velocity and moisture structure of cumulus clouds and their associated subcloud circulations, as well as to establish if these properties depend on the size of the cloud. We propose methods to compare continuous chords of cloud detected from Doppler and Raman lidars with equivalent chords derived from 1D and 3D model output. While the individual chords are highly variable, composites of thousands of observed and millions of simulated chords contain a clear signal. We find that the simulations underestimate cloud size and fraction but successfully reproduce the observed structure of vertical velocity and moisture perturbations. There is a clear scaling of vertical velocity and moisture anomalies below the chords with chord size, but the moisture anomalies are only 1 %–2 % higher than the horizontal mean values. The differences between the observations and simulations are smaller than the difference in sampling the modeled chords in time or space. The shape of the vertical velocity and moisture anomalies from cloud chords sampled spatially from 3D model snapshots is almost perfectly symmetric. In contrast, the chords sampled temporally from the lidar observations and 1D model output have a marked asymmetry, with stronger updrafts and higher moisture anomalies occurring earlier on.

This paper investigates whether the Weibull parameters of the new local approach model for cleavage fractures are affected by the geometric size of the specimen. Based on the fracture test data of A508-C steel, low temperature round notched bar tensile specimens of A508-C steel with two different notch sizes are numerically simulated by using finite element analysis software ABAQUS, and the stress distributions are obtained. The Weibull parameters of two notched bars are calibrated by linear regression method. The results show that the Weibull parameters of the specimens with different notch sizes are different. This suggests that the calibration parameters are dependent on the notch size.

The coefficients of linear thermal expansion (CLTEs) of [110] silver nanowires are studied using the molecular dynamics (MD) simulations. Silver nanowires with different diameters in a range 1.2–30 nm were modelled for this investigation. The dependences of the CLTEs on the temperature are shown. The temperature range of study was 150–450 K. The diameter of nanowire with stable CLTE on whole temperature range of investigation is established. Size influence on the CLTE of silver nanowires is described.

Strong metal-support interaction (SMSI) is one of the most important concepts in heterogeneous catalysis. Herein we report a study of Pt-TiO2 SMSI using Pt/rutile TiO2(110) model catalysts with dif...

As influence factors in generating third-order nonlinear optical (NLO) responses, several parameters, including the length of π-conjugated linkers, donor/acceptor substituents, and shape of the π e...

Convincing arguments have been presented testifying that that the surface tension of a small spherical droplet must decrease upon diminishing droplet radius in correspondence with a positive constant Tolman length. The solution of the Gibbs–Tolman–Koenig–Buff equation has been found in the most compact form. The surface tension of a small spherical droplet has been calculated within the framework of the continual approximation using the Mie–Lennard-Jones interatomic pair potential.

Studies of the coronavirus SARS-CoV-2 spread mechanisms indicate that the main mechanism is associated with the spread in the atmosphere of micro- and nanodroplets of liquid with an active agent. However, the molecular theory of aerosols of microdroplets in gases remains poorly developed. In this work, the energy properties of aerosol nanodroplets of simple liquids suspended in a gas were studied within the framework of molecular theory. The three components of the effective aerosol Hamiltonian were investigated: (1) the interaction energy of an individual atom with a liquid nanodroplet, (2) the surface energy of liquid nanodroplet, and (3) the interaction energy of two liquid nanodroplets. The size dependence of all contributions was investigated. The pairwise interparticle interactions and pairwise interparticle correlations were accounted for to study the nanodroplet properties using the Fowler approximation. In this paper, the problem of the adhesion energy calculation of a molecular complex and a liquid nanodroplet is discussed. The derived effective Hamiltonian is generic and can be used for the cases of multicomponent nano-aerosols and to account for particle size distributions.

The main result of the commented article is based on the use of an erroneous technique in the derivation of the equation for the contact angles of surface bubbles. A correct derivation gives the same Young equation as for sessile droplets, and therefore supplementary contact angles for bubbles and droplets. This cannot explain the presented results of simulations of nanosized droplets and bubbles where there are also several questions. We suggest a possible source for the difference in the contact angle size dependence for droplets and bubbles as related to the line tension and adsorptions at the interfaces.

Author(s): Abdallah, MS; Adam, J; Adamczyk, L; Adams, JR; Adkins, JK; Agakishiev, G; Aggarwal, I; Aggarwal, MM; Ahammed, Z; Alekseev, I; Anderson, DM; Aparin, A; Aschenauer, EC; Ashraf, MU; Atetalla, FG; Attri, A; Averichev, GS; Bairathi, V; Baker, W; Ball Cap, JG; Barish, K; Behera, A; Bellwied, R; Bhagat, P; Bhasin, A; Bielcik, J; Bielcikova, J; Bordyuzhin, IG; Brandenburg, JD; Brandin, AV; Bunzarov, I; Butterworth, J; Cai, XZ; Caines, H; Calderon De La Barca Sanchez, M; Cebra, D; Chakaberia, I; Chaloupka, P; Chan, BK; Chang, FH; Chang, Z; Chankova-Bunzarova, N; Chatterjee, A; Chattopadhyay, S; Chen, D; Chen, J; Chen, JH; Chen, X; Chen, Z; Cheng, J; Chevalier, M; Choudhury, S; Christie, W; Chu, X; Crawford, HJ; Csanad, M; Daugherity, M; Dedovich, TG; Deppner, IM; Derevschikov, AA; Dhamija, A; Di Carlo, L; Didenko, L; Dong, X; Drachenberg, JL; Dunlop, JC; Elsey, N; Engelage, J; Eppley, G; Esumi, S; Evdokimov, O; Ewigleben, A; Eyser, O; Fatemi, R; Fawzi, FM; Fazio, S; Federic, P; Fedorisin, J; Feng, CJ; Feng, Y; Filip, P; Finch, E; Fisyak, Y; Francisco, A; Fu, C | Abstract: We present systematic measurements of azimuthal anisotropy for strange and multistrange hadrons (Ks0, Λ, Ξ, and ω) and φ mesons at midrapidity (|y|l 1.0) in collisions of U+U nuclei at sNN=193 GeV, recorded by the STAR detector at the Relativistic Heavy Ion Collider. Transverse momentum (pT) dependence of flow coefficients (v2, v3, and v4) is presented for minimum bias collisions and three different centrality intervals. Number of constituent quark scaling of the measured flow coefficients in U+U collisions is discussed. We also present the ratio of vn scaled by the participant eccentricity (ɛn2) to explore system size dependence and collectivity in U+U collisions. The magnitude of v2/ɛ2 is found to be smaller in U+U collisions than that in central Au+Au collisions contradicting naive eccentricity scaling. Furthermore, the ratios between various flow harmonics (v3/v23/2, v4/v24/2) are studied and compared with hydrodynamic and transport model calculations.

Active galactic nuclei (AGNs) probably control the growth of their host galaxies via feedback in the form of wide-angle wind-driven outflows. These establish the observed correlations between supermassive black hole (SMBH) masses and host galaxy properties, e.g. the spheroid velocity dispersion σ. In this paper we consider the growth of the SMBH once it starts driving a large-scale outflow through the galaxy. To clear the gas and ultimately terminate further growth of both the SMBH and the host galaxy, the black hole must continue to grow its mass significantly, by up to a factor of a few, after reaching this point. The mass increment ΔMBH depends sensitively on both galaxy size and SMBH spin. The galaxy size dependence leads to ΔMBH ∝ σ5 and a steepening of the M–σ relation beyond the analytically calculated M ∝ σ4, in agreement with observation. Slowly spinning black holes are much less efficient in producing feedback, so at any given σ the slowest spinning black holes should be the most massive. Current observational constraints are consistent with this picture, but insufficient to test it properly; however, this should change with upcoming surveys.

Using the nanocrystal RP-model, the state equation of the bcc molybdenum with account of size and shape was calculated. On the basis of this equation the isobaric dependence of the melting temperature on size and shape was obtained at P = 0. It is shown, that the stronger the shape of a nanocrystal deviates from the most energetically effective one, the bigger the size of the nanocrystal at the crystallization start point. Approximation of such points for various shapes made it possible to determine the size dependence of crystallization start temperature.

Body size often varies among conspecific neonates. As larger adults generally have higher fitness than smaller conspecifics, it is adaptive for smaller neonates to subsequently gain relatively more size increments during larval development (catch‐up growth). Although catch‐up growth has been suggested in insects, inappropriate methods have been used to examine the size dependence of growth increments. Therefore, it remains unclear to what extent catch‐up growth is common among insects. The present study examined the size dependence of growth increments among larvae of Trypoxylus dichotomus using reduced major axis regression of final to initial body masses. Catch‐up growth was found consistently for larval instars. Furthermore, simulations of the size increments revealed that not only sexual divergence of the mean size, but also catch‐up growth within sexes plays a role in the development of sexual divergence in the body size distribution of T. dichotomus. The significance of catch‐up growth in body size evolution was discussed.

The size dependence of the melting point of Si nanoparticles is investigated using molecular dynamics and thermodynamic simulation based on the Thomson’s formula. The atomistic modeling data obtained using the Stillinger–Weber potential agree with the results reported by other authors and thermodynamic-simulation data and predict a decrease in the melting point Tm of Si nanoparticles with an increase in their reciprocal radius R–1 according to linear law. The available experimental data predict lower Tm values, including the limiting value $$T_{m}^{{(\infty )}}$$ , which corresponds to the linear extrapolation of experimental points to R–1 → 0 (to the radius R → ∞); the underestimation is 200–300 K as compared with the reference melting point of silicon (1688 K). It is concluded that the molecular-dynamics data on Tm(R–1) obtained using the Stillinger–Weber potential are more adequate than the available experimental data.

The linear relationship between surface tension γs and radius $$~{{R}_{{\text{s}}}}$$ of small particles (nanoparticles) was derived in the 1960s by Rusanov as $${{{\gamma }}_{{\text{s}}}} = K{{R}_{{\text{s}}}},$$ where K is the coefficient of proportionality. In this work, a more generalized dependence is obtained in the context of Gibbs’ theory of thermodynamics for curved interfaces on the same size scales for a randomly selected interface, including an equimolecular surface with radius $${{R}_{{\text{e}}}}{\text{.}}$$ It is shown that when $${{R}_{0}} \geqslant R \geqslant {\delta }$$ (where $${\delta } = {{R}_{{\text{e}}}} - {{R}_{{\text{s}}}},$$ $${{R}_{0}}$$ is a characteristic radius limiting the range of the Rusanov equation’s applicability), linear dependence $${\gamma } = KR$$ should be valid for all $$R \in \left[ {{{R}_{{\text{s}}}},{{R}_{{\text{e}}}}} \right].$$ Parameter $$K~$$ is estimated for metal nanodroplets and solid metal nanoparticles as well.

The size dependence of competitive interactions is starting to be highlighted as an important driver of species diversity within communities; however, it is still unknown whether all species are equally impacted by size‐asymmetric competition and what resources drive it. Here, we test species‐specific responses to size‐asymmetric competition under various soil environments by manipulating plant size as well as soil fertility, nutrient heterogeneity and the initial suppression of microbial communities within a three‐species community. Competition was primarily size‐asymmetric; however, the degree to which competition was size‐asymmetric was species‐specific, where three out of five soil treatments resulted in size‐asymmetric competition in some species but size‐symmetric competition in others. Overall, soil fertility and nutrient heterogeneity altered the degree of size‐asymmetric competition, while the initial suppression of microbial communities had no effect. Contrary to past predictions, when they had an effect, increased soil fertility and the presence of a high‐quality patch reduced the degree of size‐asymmetric competition, while the presence of a low‐quality patch increased it. This suggests that the role nutrient heterogeneity plays on the degree of size‐asymmetric competition is dependent on the quality and location of the patch relative to an individual's neighbours. These findings challenge the current understanding that competition for soil resources is always size‐symmetric and demonstrate that species within the same community may not experience the same degree of size‐dependent competition. These differential responses suggest we must consider variations in tolerance and suppression between species during size‐dependent plant–plant interactions, which may promote species coexistence as all small individuals may not be negatively impacted during size‐dependent competition. A plain language summary is available for this article.

Revised thermodynamic and dynamical properties of the hard sphere (HS) system are obtained from extensive molecular dynamics calculations carried out with large system sizes (number of particles, N) and long times. Accurate formulas for the compressibility factor of the HS solid and fluid branches are proposed, which represent the metastable region and take into account its divergence at close packing. Some basic second-order thermodynamic properties are obtained and a maximum in some of their derivatives in the metastable fluid region is found. The thermodynamic parameters associated with the melting-freezing transition have been determined to four digit accuracy, which generates accurate new values for the coexistence properties of the HS system. For the self-diffusion coefficient, D, it is shown that relatively large systems (N > 10 4 ) are required to achieve an accurate linear extrapolation of D to the infinite size limit with a D vs. N -1/3 plot. Moreover, it is found that there is a density dependence of the value of the slope in the linear regime. The density dependent correction becomes practically insignificant at higher densities and the hydrodynamic formula found in the literature is still accurate. However, with decreasing density the density dependence of the size correction cannot be neglected, which indicates that other sources of N-dependence, apart from those derived on purely hydrodynamic grounds, may also be important (and as yet unaccounted for). A detailed analytic representation of the density dependence of the HS self-diffusion coefficient and the HS viscosity, η, is given. It is shown that the HS viscosity near freezing and in the metastable region can be described well by the Krieger-Dougherty equation. Both D and η start to scale at high densities and in the metastable region in such a way that Dη p = const, where p ≃ 0.97, and D → 0 and η → ∞ at a packing fraction of 0.58, which coincides with some previous predictions of the HS glass transition density.

The magnitude of postseismic slip is useful for constraining physical models of fault slip. Here we examine the postseismic slip following intermediate‐magnitude (M 4 to 5) earthquakes by systematically analyzing data from borehole strainmeters in central and northern California. We assess the noise in the data and identify 11 earthquakes that generated interpretable strain records. We estimate the earthquakes' postseismic to coseismic moment ratios by comparing the coseismic strain changes with strain changes induced by afterslip in the following 1.5 days. The median estimated postseismic moment is 0.45 times the coseismic moment, with a 90% confidence interval between 0.25 and 0.60. This postseismic moment is slightly larger than typically observed following large (M > 6) earthquakes but smaller than observed following small (M2 to 4) earthquakes. The intermediate‐magnitude postseismic slip suggests a size dependence in the dynamics of earthquakes or in the properties of fault areas that surround earthquakes.

Kirkwood-Buff integration (KBI) is implemented into the massively-parallel molecular simulation tool ms2 and assessed by molecular dynamics simulations of binary liquid mixtures. The formalism of Kruger et al. (P. Kruger et al., J. Phys. Chem. Lett. 4: 235–238, 2013) that adopts NVT ensemble data to the μVT ensemble is employed throughout. Taking advantage of its linear scaling with inverse system size, the extrapolation to the thermodynamic limit is analyzed. KBI are calculated with standard radial distribution functions (RDF) and two corrected RDF forms. Simulations in the NVT ensemble are carried out in the entire composition range for four Lennard-Jones mixtures, studying system size dependence by varying N = 4000, 8000 and 16000 molecules. Moreover, four mixtures of “real” components are considered with N = 4000. Thermodynamic factor, partial molar volumes and isothermal compressibility are calculated from KBI and compared with benchmark data from NpT ensemble simulations. The assessment shows that the formalism of Kruger et al. greatly improves KBI and that extrapolation is important, particularly for smaller systems.

In this work, we have synthesized and characterized three differently sized (3.1, 5.7, and 9.3 nm) methylammonium lead bromide (CH3NH3PbBr3) perovskite nanocrystals (PNCs) and passivated using (3-a...

The yield surface in crystal plasticity can be approached from various directions during mechanical loading. We consider the competition between nanoindentation and tensile loading towards plastic yielding. For this purpose, we develop a two-dimensional discrete dislocation model that is then utilized to investigate the hardness and pop-in event statistics during nanoindentation of single crystal under tensile pre-stress. Indentation is performed by using cylindrical (circular in 2D) indentation with varying radius and under both displacement and load control. Tensile in-plane stress, varying from zero to yield strength, is assigned to investigate the effect of pre-stress on hardness and pop-in statistics. At small indentation depths, the measured hardness is found to be smaller for larger tensile pre-stress; therefore, we conclude that nanoindentation can be used to detect plasticity. When indentation depth is larger, the effect of pre-stress is barely seen. Moreover, we discuss event statistics and the related effect of pre-stress., 27 pages, 13 figures

As many other glass formers do, bulk-metallic-glass (BMG) forming melts undergo a fragile-to-strong transition (FST), which is accompanied by a small but noticeable peak in the specific heat c p . Because of this peak, the FST is sometimes interpreted as a smeared-out phase transformation. Finite-size scaling analysis of peaks in c p allows the order of a phase transition to be accurately determined. This motivated us to study c p along with structural and dynamical properties of a ternary BMG former (Zr0.606Cu0.29Al0.104) using computer simulations, in which the system size was varied in a well-controlled fashion. Our model system reproduces the typical, almost discontinuous cross-over between non-Arrhenius to Arrhenius-type dynamics, which defines the FST. However, in contrast to the expectations for a phase transformation, the larger the system the smaller the peak in c p . Other properties also reveal a size dependence, which is difficult to reconcile with the interpretation of the FST being a (smeared-out) phase transformation resulting from the competition between different local structures.

For a bubble on a smooth and rigid substrate, its contact angle is always assumed to be supplementary to the droplet contact angle under the same wetting conditions. Here we revisit bubble wetting on smooth solid surfaces via both free energetic analysis and molecular dynamics (MD) simulations. Our study shows a fundamental difference between bubble wetting and droplet wetting: the size dependence of the isothermal compressibility of the gas bubble leads to a size-dependent bubble contact angle. Based on theoretical analysis we develop a new relationship between the bubble contact angle and droplet contact angle, which is verified with MD simulations for nano-sized bubbles and droplets. In general, our studies show that for bubbles having a size greater than 10 micrometers, the traditional relation of the bubble contact angle being supplementary to the droplet contact angle holds. But when the bubble size decreases to several micrometers or even to the nanoscale size, the relation of contact angle match breaks down, and the deviation from contact angle match increases with decreasing bubble size. This study reveals a unique wetting behavior of bubbles, implying that the wetting of micro- and nano-bubbles deserves serious consideration.

A simple model for the size dependence of liquid–vapor surface energy of a liquid drop, free of any adjustable parameter, has been extended for the size dependence of the surface energy of nanovoids in this work. Considering nanovoids, there is a negative curvature on the void surface, which is completely different from nanoparticles or liquid drops, which have positive curvature surfaces. Thus curvature has an important effect on material properties. Moreover, by introducing negative curvature into the model for deduction of liquid–vapor surface energy, a successful prediction for the behaviour of argon (Ar) and silicon (Si) surface energy on the surface of nanovoids are obtained, which further confirms the role of curvature. Furthermore, it is shown that the surface energy of nanovoids increases as void size is reduced, suggesting a greater difference in energy between surface atoms and interior atoms, especially when void size is smaller than 4 nm. This is owing to the fact that the surface energy gradually approaches that of the bulk when the void size is larger than 4 nm. Thus, the effect of size on the surface energy of voids is significant when the voids are of small dimensions.

A stochastic age-structured population model with immigration of individuals is considered. We assume that the lifespan of each individual is a random variable with a distribution function which may differ fromthe exponential one. The immigration rate of individuals depends on the time and total population size. Upper estimates for the mean and variance of the population size are established based on the theory of branching processes with constant immigration rate. A Monte Carlo simulation algorithm of population dynamics is developed. The results of numerical experiments with the model are presented.

We report on the size dependence of the Ag–Cu nano-alloy melting temperatures via differential scanning calorimetry (DSC) measurements of silica-coated Ag–Cu nanoparticles (NPs) and the thermodynam...

The size dependences of the melting and crystallization temperatures of silver nanoparticles are obtained by two alternative atomistic simulation methods, such as the molecular dynamics and Monte-Carlo methods. The simulation results are analyzed and compared with available experimental values and a melting temperature calculated using the well-known Thomson formula. Atomistic simulation reveals good coincidence between the data and satisfactorily conforms to the Thomson formula. However, the melting temperatures predicted through atomistic simulations exceeds the available experimental data.

It is shown that the inclusion of hadronic interactions, and in particular nuclear potentials, in simulations of heavy ion collisions at the SPS energy range can lead to obvious correlations of protons. These correlations contribute significantly to an intermittency analysis as performed at the NA61 experiment. The beam energy and system size dependence is studied by comparing the resulting intermittency index for heavy ion collisions of different nuclei at beam energies of $40A$, $80A$ and $150A$ GeV. The resulting intermittency index from our simulations is similar to the reported values of the NA61 collaboration, if nuclear interactions are included. The observed apparent intermittency signal is the result of the correlated proton pairs with small relative transverse momentum $\Delta p_{t}$, which would be enhanced by hadronic potentials, and this correlation between the protons is slightly influenced by the coalescence parameters and the relative invariant four-momentum $q_{inv}$ cut., Comment: 6 pages, 6 figures

Sinking particles are critical to the ocean's “biological pump,” sequestering carbon from the atmosphere. Particles' sinking speeds are a primary factor determining fluxes and subsequent ecological and climatic impacts. While size is a key determinant of particles' sinking speeds, observations suggest a variable size-sinking relationship, affected by other particle properties, resulting in substantial spread in parameterizations of particle sinking and fluxes. We compile particle size-sinking observations and apply hierarchical Bayesian statistical models to resolve the size-sinking relationship while accounting for other factors. We find an overall scaling close to the general Navier-Stokes drag equation, and differences between particle types, open ocean versus coastal/laboratory particles, and in situ versus ex situ methods. These results can help harmonize how Earth system models parameterize particle fluxes and support a weaker size-dependence than often assumed, with implications for the flux contribution of small particles and the predicted future shrinking of marine particle populations.

Recent results for high multiplicity pp and p-Pb collisions have revealed that they exhibit heavy-ion-like behaviors. To understand the origin(s) of these unexpected phenomena, event shape observables such as transverse spherocity ($S_{\rm 0}^{p_{\rm T} = 1}$) and the relative transverse activity classifier ($R_{\rm{T}}$) can be exploited as a powerful tools to disentangle soft (non-perturbative) and hard (perturbative) particle production. Here, the production of light-flavor hadrons is shown for various $S_{\rm 0}^{p_{\rm T} = 1}$ classes in pp collisions at $\sqrt{s}$ = 13 $\textrm{TeV}$ measured with the ALICE detector at the LHC are presented. The evolution of average transverse momentum ($\langle p_{\rm T}\rangle$) with charged-particle multiplicity, and identified particle ratios as a function of $p_{\rm T}$ for different $S_{\rm 0}^{p_{\rm T} = 1}$ are also presented. In addition, the system size dependence of charged-particle production in pp, p-Pb, and Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV is presented. The evolution of $\langle p_{\rm T}\rangle$ in different topological regions as a function of $R_{\rm{T}}$ are presented. Finally, using the same approach, we present a search for jet quenching behavior in small collision systems., Proceedings of "The 5th International Conference on Particle Physics and Astrophysics", 5-9 October 2020 (Online)

The size-dependent behavior of nanofilms and nanodroplets of homologous polymer blends was explored by many-body dissipative particle dynamics. Although a homologous blend can be regarded as a completely miscible and athermal system, enrichment of the surface in short polymers always takes place. First, liquid–gas and solid–liquid interfacial tensions of polymer melts were acquired. It is found that they increase and approach asymptotes with increasing chain lengths. The molecular weight dependence can be depicted using two semi-empirical expressions. Second, the variation of surface tension and surface excess of polymer blend nanofilms with the thickness was observed. Surface tension of the blend is observed to increase but the extent of surface segregation decreases upon increasing the film thickness. Finally, the wetting phenomenon of nanodroplets of homologous blends was examined. The contact angle is found to increase as the droplet size is reduced. Our simulation results indicate that the size-dependence of nanofilms and nanodroplets is closely related to surface segregation in homologous blends.

International audience; Phase nucleation and propagation phenomena can be characterized by a cooperative behavior regulated by non local interactions between the multistable domains and with the loading device. Cooperativity is often macroscopically witnessed by a stress-peak, distinguishing the nucleation from the propagation stress, and by a larger size of the first nucleated domain. When low dimensional scales are considered, both in nanostructures or single molecule behaviors, the interfacial energy can compete with entropic effects, leading to the experimental observation of a temperature dependent phase transition strategy. We propose a fully analytical model, in the framework of Statistical Mechanics, measuring such energetic competition and temperature dependent behavior, that well reproduces important experimental evidences. The effectiveness of the model is successfully tested in predicting the temperature dependent phase transition behavior of shape memory nanowires.

International audience

This work presents the results of our study of Back-End-of-Line (BEOL)-processed Hf 0.5 Zr 0.5 O 2 (HZO)-based Metal-Ferroelectric-Metal (MFM) capacitors fabricated at temperatures never exceeding 400 0C, and over a wide range of areas (10˗2 to 103 µm2). These devices exhibit very tight distributions throughout the 12-in wafers that we measured, as well as neglectable size dependence. This work also presents our current understanding of the wake-up issue, and suggestion for possible ways of device engineering. In addition, the potential for automotive applications is demonstrated based on the results of a set of MFM devices systematically measured and analyzed at elevated temperatures (150-427 0C).

We conducted$^{195}$Pt-nuclear magnetic resonance measurements on various-diameter Pt nanoparticles coated with polyvinylpyrrolidone in order to detect the quantum size effect and the discrete energy levels in the electron density of states, both of which were predicted by Kubo more than 50 years ago. We succeeded in separating the signals arising from the surface and interior regions and found that the nuclear spin-lattice relaxation rates in both regions show the metallic behavior at high temperatures. Surprisingly, the magnetic fluctuations in both regions exhibited anomalous behavior below the same temperature $T^*$, which points to a clear size dependence and is well scaled with $\delta_\mathrm{Kubo}$. These results suggest that a size-tunable metal-insulator transition occurs in the Pt nanoparticles as a result of the Kubo effect., Comment: 11 pages, 10 figures, including supplemental materials, accepted for publication in Phys. Rev. B as a Rapid Communication

Nanometer-sharp objects coupled with femtosecond laser pulses find much current interest because they allow us to reach high spatiotemporal control -- like a needle tip enables the scanning tunneling microscope (STM). With two needles facing each other, a special nanometric gap is formed, facilitating large optical near fields. Here, the authors experimentally retrieve the optical near fields of femtosecond laser pulses present in a nanogap as a function of the gap size, bearing direct ramifications for plasmonics and strong-field physics.

The occupancy distribution of water molecules in the first hydration shell around a solute is intimately connected with solvent density fluctuations and is of fundamental interest in understanding hydration. The free energies to evacuate the first hydration shell around a solute and a cavity defined by the first hydration shell depend on the system size, emphasizing that the solvent density fluctuations are themselves dependent on the system size. This observation interpreted within the quasichemical theory shows that both the hydrophilic and the hydrophobic contributions to hydration depend on the system size, decreasing with increasing system size. The net hydration free energy benefits somewhat from the compensation of hydrophilic and hydrophobic contributions; nevertheless a large system appears necessary to describe correctly the balance of these contributions in the hydration of the macromolecule.

Thermal rectification which is a diode-like behavior of heat flux has been studied over a long time. However, a universal and systematic physical description is still lacking. In this letter, a perturbation theory of thermal rectification is developed, which provides an analytical formula of the thermal rectification ratio. It reveals the linear relationship between the thermal rectification ratio and temperature difference. Furthermore, the size-dependence of the thermal rectification relies on the specific form of the thermal conductivity. In addition, several experimental and numerical observations in previous literatures are well explained. This theory can be applicable to any system in which a differentiable effective thermal conductivity can be derived, and is helpful to unveil general principle for thermal rectification., Comment: 5 pages, 2 figures, 50 references, 1 supplemental material

Significance Organismal responses to climate change are mediated through its effects on physiology and metabolism. In aquatic environments, both water temperature and oxygen availability may modulate these responses by altering the aerobic metabolism fueling physiological performance. However, ecological models aimed at predicting how environmental factors shape aerobic metabolism disregard the role of oxygen supply. Here, we expand on these models by explicitly incorporating oxygen supply. Our results show that warmer water increases oxygen demand relative to supply, and the resulting reduction in aerobic scope appears to be stronger in larger individuals. Smaller aerobic scopes in warming water imply that climate change will reduce energy budgets needed to support the activities of aquatic animals and their physiological performance in the future., Both oxygen and temperature are fundamental factors determining metabolic performance, fitness, ecological niches, and responses of many aquatic organisms to climate change. Despite the importance of physical and physiological constraints on oxygen supply affecting aerobic metabolism of aquatic ectotherms, ecological theories such as the metabolic theory of ecology have focused on the effects of temperature rather than oxygen. This gap currently impedes mechanistic models from accurately predicting metabolic rates (i.e., oxygen consumption rates) of aquatic organisms and restricts predictions to resting metabolism, which is less affected by oxygen limitation. Here, we expand on models of metabolic scaling by accounting for the role of oxygen availability and temperature on both resting and active metabolic rates. Our model predicts that oxygen limitation is more likely to constrain metabolism in larger, warmer, and active fish. Consequently, active metabolic rates are less responsive to temperature than are resting metabolic rates, and metabolism scales to body size with a smaller exponent whenever temperatures or activity levels are higher. Results from a metaanalysis of fish metabolic rates are consistent with our model predictions. The observed interactive effects of temperature, oxygen availability, and body size predict that global warming will limit the aerobic scope of aquatic ectotherms and may place a greater metabolic burden on larger individuals, impairing their physiological performance in the future. Our model reconciles the metabolic theory with empirical observations of oxygen limitation and provides a formal, quantitative framework for predicting both resting and active metabolic rate and hence aerobic scope of aquatic ectotherms.

Sensitization of organic molecules by semiconductor nanocrystals is a promising way to boost the absorption of the former, important for applications in fluorescence labeling and photocatalysis. Se...

We performed Monte Carlo simulation of the pseudo-spin Ising model in a two-dimensional ferroelectric system. The Metropolis method was employed by studying the size dependence of dielectri...

Size dependences of melting and crystallisation entropies of metal nanoparticles (of copper and gold) have been studied using atomistic simulation results (molecular dynamics and Monte Carlo) and some theoretical considerations. The size dependence of melting entropy is more pronounced than that of crystallisation entropy. The behaviour of the size dependence of the melting entropy has been found to be complex and ambiguous. However, all thermodynamic models predict that the melting entropy of nanoparticles is lower than the corresponding bulk value and increases with growing particle size, and tends to the bulk value when the particle size tends to infinity.

A modified Weibull model incorporating the within-fibre diameter variation is applied to examine the fibre diameter effect on the strength of single fibres. Australian Superfine Merino Wool (ASFW) and Inner Mongolia Cashmere (IMC) were used in the present work, since these animal fibres tend to have relatively large diameter variations. To determine single fibre strength, tensile measurements were carried out for fibres with diameters varying between 9 and 21 μm at a constant gauge length. It was found that an increase in the diameter disparity along the fibre reduces the strength of fibres. To validate this, the accuracy of predicting weak-link scaling was evaluated; the results showed that the application of modified Weibull distribution gives a better relationship with the empirical data than the standard Weibull model. The results suggest that the modified Weibull model is more accurate in predicting the size dependence and strength of single fibres with diameter variations.

Compression of nanoporous gold in situ under electrochemical control reveals that its flow stress can be enhanced by surface coverage of monolayer oxide. Here we present a study on the monolayer oxide induced changes in flow stress of an nanoporous gold, while the ligament size is varied by more than 2 orders of magnitude. The increase percentage of flow stress (of nanoporous gold and nano-ligaments) induced by surface monolayer oxide is negligible when the ligament size (L) exceeds ∼2 µm, increases with decreasing L for ∼200 nm

The concentration of heavy metals in urban road-deposited sediments (RDS) can be used as an indicator for environmental pollution. Thus, their occurrence has been studied in whole road dust samples as well as in size fractions obtained by sieving. Because of the limitations of size separation by sieving little information is available about heavy metal concentrations in the road dust size fractions20 μm. In this study air classification was applied for separation of dust size fractions smaller than 20 μm from RDS collected at different times during the year. The results showed only small seasonal variations in the heavy metals concentrations and size distribution. According to the Geoaccumulation Index the pollution of the road dust samples deceased in the following order: Sb » As Cu ≈ Zn Cr Cd ≈ Pb ≈ Mn Ni Co ≈ V. For all heavy metals the concentration was higher in the fine size fractions compared to the coarse size fractions, while the concentration of Sr was size-independent. The enrichment of the heavy metals in the finest size fraction compared to the whole RDS200 μm was up to 4.5-fold. The size dependence of the concentration decreased in the following order: Co ≈ Cd Sb (Cu) ≈ Zn ≈ Pb As ≈ V » Mn. The approximation of the size dependence of the concentration as a function of the particle size by power functions worked very well. The correlation between particle size and concentration was high for all heavy metals. The increased heavy metals concentrations in the finest size fractions should be considered in the evaluation of the contribution of road dust re-suspension to the heavy metal contamination of atmospheric dust. Thereby, power functions can be used to describe the size dependence of the concentration.

The study reported in this paper addresses an aspect of the modelling of particle stratification as it applies to the processing of minerals. It focuses on the phenomenological model developed by King and the extent to which the single parameter in that model, i.e. the stratification index, is dependent on the size of particles in the stratifying system. Based on a careful experimental investigation in a batch jig, the study found that, contrary to expectation and current theory, the size dependence of the index is weak or absent over the range of conditions investigated. The implications of the findings for both theory and modelling practice and for Rao’s proposed modification of King’s model are discussed. The study also presents a number of findings related to experimental procedures for obtaining precise measurements of parameters in stratification models.