Article
Chemistry, Physical
Umang A. Dattani, Smarajit Karmakar, Pinaki Chaudhuri
Summary: It has been found that micro-alloying with inclusions can enhance the fracture toughness and delay the occurrence of cavitation in amorphous solids. Additionally, pinning particles can regulate the plastic activity, resulting in a spatially homogeneous distribution of cavities.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Engineering, Chemical
Celine Ruscher, Joerg Rottler
Summary: The study focused on the statistical properties of the yielding transition in model amorphous solids under slow, athermal deformation, revealing plastic flow through a combination of elastic loading and collective avalanches. The spatial extent of avalanches and degree of stress correlations change as deformation progresses. It was found that the statistics of stress and energy drops only become comparable for large events in the steady flow regime.
Article
Materials Science, Multidisciplinary
Jack T. Parley, Rituparno Mandal, Peter Sollich
Summary: We studied the linear response to strain in a mean-field elastoplastic model for athermal amorphous solids, incorporating the power-law mechanical noise spectrum arising from plastic events. In the jammed regime of the model, we found that the stress relaxes incompletely to an age-dependent plateau, on a timescale which grows with material age. We analytically determined the scaling behavior of this aging linear response and found that key scaling exponents are universal and independent of the noise exponent mu.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Materials Science, Ceramics
Karina Gonzalez-Lopez, Eran Bouchbinder, Edan Lerner
Summary: Quantifying mechanical disorder in solids, such as disordered crystals and glassy solids, is crucial for understanding their structure-properties relations. However, the bounds and variability of mechanical fluctuations in these disordered solids, as well as their dependence on formation history, remain unknown. In this study, a quantifier of mesoscopic mechanical disorder x, based on shear modulus fluctuations, is investigated in various disordered computer solids. The results reveal important relationships between x and fundamental properties of disordered solids, and highlight the potential divergent behavior of x in systems approaching the critical unjamming point.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Astronomy & Astrophysics
Mariana A. Fazio, Gabriele Vajente, Le Yang, Alena Ananyeva, Carmen S. Menoni
Summary: This study presents a systematic investigation on amorphous metal oxide and Ta2O5-based mixed oxide coatings for low Brownian noise experiments. The mechanical loss of metal oxides is found to be correlated with their amorphous morphology, with SiO2 and GeO2 showing the lowest loss angles. The influence of the dopant in the optical and elastic properties of the coating is also studied. The study concludes that TiO2-doped Ta2O5 is the optimal choice for reduced thermal noise among Ta2O5-based mixed oxide coatings with low dopant concentrations.
Article
Physics, Multidisciplinary
R. Santhosh Kumar, Bhaskar Sen Gupta
Summary: We simulate the shear-induced fluidization of amorphous solids under external loading and investigate their relaxation dynamics. By applying simple shear deformation to thermal glassy materials, we study shear localization and plastic deformation heterogeneity using non-affine displacement field. The enhanced particle mobility with strain, reflected by mean square displacement, indicates material fluidization. We estimate the relaxation time of sheared glasses using time correlation function, observing a significant decrease in relaxation time as the material transitions from solid to liquid-like. Additionally, we analyze the imprint of the quiescent sample on the rheological properties of the shear melted glass by analyzing the relaxation of shear stress and find a finite persistent residual stress.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Takumi Yamada, Masayuki Yamaguchi, Takumitsu Kida
Summary: This study generated cross orientation between lamellae and amorphous chains in a thermoplastic polyester elastomer (TPEE) through processing methods. The formation of residual crystals led to prolonged relaxation and affected the processability during extrusion.
ACS APPLIED POLYMER MATERIALS
(2022)
Review
Physics, Multidisciplinary
Xiangying Shen, Guimei Zhu, Baowen Li
Summary: The primary research of physics is to uncover the underlying laws governing the physical world. However, for complex systems like amorphous networks, even with knowledge of component details, predicting collective behavior can be challenging due to emergence phenomena. Non-affine mechanical responses are common in these networks, hindering the understanding of their intrinsic properties and mechanical behaviors. Recent findings on an amorphous network with almost perfect affine behavior derived from jammed particles offer insights into the factors influencing network affinity. This article provides a concise review of the latest advances in this field.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2023)
Article
Medicine, Research & Experimental
Savitha Thayumanasundaram, Thulasinath Raman Venkatesan, Aymeric Ousset, Kim Van Hollebeke, Luc Aerts, Michael Wubbenhorst, Guy Van den Mooter
Summary: In this study, different solid-state characterization techniques were used to comprehensively characterize molecular relaxations, miscibility, and molecular interactions in amorphous solids. The results showed that the different techniques complement each other in determining the glass transition temperature (T-g) and sub-T-g transitions, providing insights into the effect of drug loading on T-g.
MOLECULAR PHARMACEUTICS
(2022)
Article
Astronomy & Astrophysics
S. Khadka, A. Markosyan, K. Prasai, A. Dana, L. Yang, S. C. Tait, I. W. Martin, C. S. Menoni, M. M. Fejer, R. Bassiri
Summary: The mechanical loss of amorphous thin films of germania (GeO2) and titania-doped germania (Ti:GeO2) on silicon double-paddle oscillators was investigated. The study found that undoped germania exhibited a wide cryogenic mechanical loss peak centered at around 60K, with a rate of 3.1x10-3, which decreased to 1.1x10-3 as the Ti-concentration increased to 44%. Ti-doping not only decreased the height of the low-temperature peak, but also increased its width and shifted its position to lower temperatures. Annealing reduced the room temperature mechanical loss of Ti:GeO2 and increased its cryogenic mechanical loss, consistent with trends observed in most amorphous oxides.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Environmental Sciences
Aggelos Tsaligopoulos, Stella Kyvelou, Nefta-Eleftheria Votsi, Aimilia Karapostoli, Chris Economou, Yiannis G. Matsinos
Summary: Numerous studies have shown that environmental noise is a significant pollutant in urban areas. Different methods have been used to calculate, visualize, predict, and mitigate its effects. The concept of quietness in urban environments has been revisited in this study, introducing a new composite index called the Composite Urban Quietness Index (CUQI) that focuses solely on quantifiable metrics for assessing the acoustic environment. The research has concluded that CUQI is functioning effectively even in the early stages of development, verifying previous findings on quiet areas in the city of Mytilene, Greece.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2021)
Article
Chemistry, Physical
Jixiang Li, Abderrahim Maazouz, Khalid Lamnawar
Summary: This study investigates the effects of shear flow on the behaviors of nanofiller evolution inside linear and long chain branched polymer matrices. The results reveal that the percolation threshold of the nanocomposites with long chain branching is higher than that of the linear polymer matrices. The liquid-solid transitions and electrical conductivities of the nanocomposites depend on the shear flow conditions.
Article
Materials Science, Multidisciplinary
Alberto Martinelli, Mauro Giovannini, Martina Neri, Gianluca Gemme
Summary: Amorphous films of tantalum oxide (Ta2O5) are widely used in constructing highly reflective mirrors in interferometric gravitational wave detectors. Despite numerous studies, the local structural properties of amorphous Ta2O5 still require further investigation. Ti doping can retain the short-range ordering in amorphous films, while pure Ta2O5 undergoes significant rearrangement of local structure after thermal treatment.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Multidisciplinary Sciences
Alexandre Nicolas, Marcelo Kuperman, Santiago Ibanez, Sebastian Bouzat, Cecile Appert-Rolland
SCIENTIFIC REPORTS
(2019)
Article
Materials Science, Multidisciplinary
D. Richard, M. Ozawa, S. Patinet, E. Stanifer, B. Shang, S. A. Ridout, B. Xu, G. Zhang, P. K. Morse, J-L Barrat, L. Berthier, M. L. Falk, P. Guan, A. J. Liu, K. Martens, S. Sastry, D. Vandembroucq, E. Lerner, M. L. Manning
PHYSICAL REVIEW MATERIALS
(2020)
Review
Physics, Multidisciplinary
Chen Liu, Suman Dutta, Pinaki Chaudhuri, Kirsten Martens
Summary: The authors developed a framework to study the mechanical response of athermal amorphous solids by coupling mesoscale and microscopic models. They presented a coherent elastoplastic model approach for deformation and flow of yield stress materials using measurements of coarse-grained quantities from simulations. This model allows matching transient and steady state features of driven disordered systems with diverse preparation histories consistently.
PHYSICAL REVIEW LETTERS
(2021)
Article
Transportation
Alexandre Nicolas, Fadratul Hafinaz Hassan
Summary: This review discusses the importance of pedestrian group modeling in crowd simulation and provides a discussion of the main strategies for modeling such groups, offering guidance for prospective modelers.
TRANSPORTMETRICA A-TRANSPORT SCIENCE
(2023)
Article
Chemistry, Physical
Chen Liu, Ezequiel E. Ferrero, Eduardo A. Jagla, Kirsten Martens, Alberto Rosso, Laurent Talon
Summary: The behavior of shear-oscillated amorphous materials is studied using a coarse-grained model. It is found that the steady-state behavior is determined by the initial preparation and the oscillation amplitude. The transient regime characterizing the growth and motion of the shear band is also investigated.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Engineering, Industrial
Willy Garcia, Simon Mendez, Baptiste Fray, Alexandre Nicolas
Summary: This study evaluates the risks of Covid-19 spread in various daily-life situations involving crowds, and develops a method for inferring the global number of new infections. Factors such as crowd density and the geometric shape of queues are found to significantly affect disease transmission risks.
Article
Multidisciplinary Sciences
Inaki Echeverria-Huarte, Alexandre Nicolas, Raul Cruz Hidalgo, Angel Garcimartin, Iker Zuriguel
Summary: This study demonstrates that pedestrians roaming in an enclosure form vortex-like patterns that only rotate counterclockwise. By conducting numerical simulations, it is revealed that the formation of swirls in many-particle systems can be seen as a phase transition influenced by the density of agents and their interactions with boundaries. Additionally, the preference of right-handed pedestrians to turn left when facing a wall is identified as the symmetry breaking mechanism that triggers the observed global counterclockwise rotation.
SCIENTIFIC REPORTS
(2022)
Article
Operations Research & Management Science
Nilankur Dutta, Thibault Charlottin, Alexandre Nicolas
Summary: Parking is a crucial element in transportation policies, with significant impacts on pollution and congestion. However, the laws governing parking search time lack transparency, hindering a comprehensive understanding. This study provides a mathematical formulation to analyze the role of street networks and the unequal attractiveness of parking spaces in parking search. Through computational and analytical methods, the research clarifies the parameters controlling search time and offers insights applicable to both simplified and complex street networks.
TRANSPORTATION SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Simon Mendez, Willy Garcia, Alexandre Nicolas
Summary: Short-range exposure to virus-laden respiratory droplets in the air is an effective way of transmitting respiratory diseases, and it is important to assess the risks in daily-life settings involving many individuals. This study bridges the gap between fluid dynamical simulations and population-scale epidemiological models by simulating droplet trajectories, mapping viral concentration, and combining these maps with field-data about crowded scenarios. The results indicate the importance of airflow velocity relative to the emitter's motion and provide a ranking of infection risks in different scenarios.
Article
Physics, Fluids & Plasmas
Thibault Bonnemain, Matteo Butano, Theophile Bonnet, Inaki Echeverria-Huarte, Antoine Seguin, Alexandre Nicolas, Cecile Appert-Rolland, Denis Ullmo
Summary: Most models assume that pedestrians' local navigation involves no anticipation beyond imminent collisions. However, these models often fail to replicate key features observed experimentally, such as transverse movements towards regions of higher density in dense crowds crossed by an intruder. In this study, we propose a minimal model based on mean-field games, which emulates agents planning global strategies to minimize overall discomfort. By solving the problem in the permanent regime using an analogy with the nonlinear Schrodinger's equation, we identify the two main variables governing the model's behavior and thoroughly investigate its phase diagram. Compared to prominent microscopic approaches, the model successfully replicates the experimental observations associated with the intruder experiment and can also capture other daily-life situations such as partial metro boarding.
Article
Transportation Science & Technology
Inaki Echeverria-Huarte, Alexandre Nicolas
Summary: Pedestrians have the ability to anticipate and navigate in cluttered spaces, but this ability is impaired by digital distraction from smartphones. A continuous agent-based model called ANDA is proposed to capture these features and successfully replicate empirical observations in various scenarios. This model provides insights into the origin of its current limitations and the unique position of pedestrian crowds in active matter systems.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2023)
Article
Chemistry, Physical
Vishwas V. Vasisht, Pinaki Chaudhuri, Kirsten Martens
Summary: In soft amorphous materials, the origin and distribution of residual shear stress after shear cessation are investigated using molecular dynamics simulations. It is found that increasing shear rate prior to cessation leads to lower residual stress states. The findings are rationalized using a mesoscopic elasto-plastic description, which includes a long range elastic response to local shear transformations.
Article
Chemistry, Physical
Luca Cipelletti, Kirsten Martens, Laurence Ramos
Article
Chemistry, Physical
Raffaela Cabriolu, Jurgen Horbach, Pinaki Chaudhuri, Kirsten Martens
Article
Materials Science, Multidisciplinary
Magali Le Goff, Eric Bertin, Kirsten Martens
JOURNAL OF PHYSICS-MATERIALS
(2020)