Article
Chemistry, Physical
Julien Lombard, Thierry Biben, Samy Merabia
Summary: This study examines the photoacoustic response of gold core-silica shell nanoparticles in water and explores the role of interfacial coupling between gold electrons and silica shell phonons, as well as the impact of nanocavitation on acoustic response.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Physics, Multidisciplinary
Tine Curk, Erik Luijten
Summary: Nanoparticles in solution acquire charge through surface groups, requiring the use of charge-regulating boundary conditions for proper description of electrostatic interactions. A hybrid Monte Carlo/molecular dynamics scheme is implemented to dynamically adjust charges of surface groups, qualitatively changing self-assembled structures. The conventional constant-charge approximation may be used under certain conditions, and the interplay between charge regulation and dielectric polarization is clarified.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
B. Ibarra-Tandi, J. A. Moreno-Razo, J. Munguia-Valadez, J. Lopez-Lemus, M. A. Chavez-Rojo
Summary: This study conducted molecular simulations on a two-dimensional simple fluid using non conformal molecular interactions, exploring the effects of softness parameters on fluid properties and the model's versatility in different systems, while also evaluating the impact of system dimensionality. The results demonstrated the predictive capacity and robustness of the interaction model, highlighting the importance of distinguishing between repulsive and attractive contributions in molecular interaction models for a better understanding of thermodynamic properties of simple and complex fluids.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Physics, Multidisciplinary
Junjie Chen, Zhiwei Pang
Summary: This study numerically investigates the quasi-ballistic heat conduction properties of phonons in a multi-material system and the variations of phonon mean free path with different modulation frequencies. The results indicate that the modulation frequency does not affect the effective thermal conductivity of the system, and the effect of quasi-ballistic heat conduction is noticeable even in semiconductor alloys at room temperature.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Chemistry, Multidisciplinary
Francesco Maria Bellussi, Carlos Saenz Ezquerro, Manuel Laspalas, Agustin Chiminelli
Summary: The interfacial characteristics of graphene-based polymer nanocomposites were studied using a molecular dynamics approach, revealing the significant role of oxidation degree in influencing the studied properties of the interfacial region. The interaction energy between different polymer matrices and graphene fillers varied based on the polarity of the polymer matrix molecules and the Coulombic component contribution.
Article
Chemistry, Physical
Gen Lin, Lan Jiang, Pengfei Ji
Summary: A two-temperature model with a metal-nonmetal interface is used to investigate the heat transfer across metal-nonmetal interfaces during femtosecond laser processing of thin metal films. Inserting an interlayer and reducing the interfacial thermal resistance enhance heat transfer. This affects temperature distributions and also impacts the thermal reflectivity detection and laser processing of thin metal films.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Applied
Dongbo Li, Haiying Yang, Lin Li, Ping Yang
Summary: The purpose of this work is to investigate the contribution of in-plane and out-of-plane phonon modes to interface thermal conductivities (ITC) of the Cu/graphene/Cu interface through nonequilibrium molecular dynamics simulations. The proportions of the ITC of the in-plane and out-of-plane phonon modes in the pristine ITC are 1.1% and 99.3%, respectively. Defect engineering can change the coupling strength between in-plane and out-of-plane phonon modes. There is a strong coupling between the in-plane and the out-of-plane phonon mode when the defect concentration is lower than 3%. Phonon coupling has been transformed into weak interaction when the defect concentration is higher than 3%. The high defect concentration can suppress the coupling between in-plane and out-of-plane phonon modes. The results of the phonon density of states show that the out-of-plane phonons are mainly concentrated at low frequencies, and the in-plane phonons are mainly concentrated at high frequencies. This work helps to understand the mechanism of heat transfer of the graphene-based interface and provides theoretical guidance for the application of graphene-based interface nanodevices.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Hai Huang, Yinghui Zhong, Bin Cai, Jiefang Wang, Zhongxia Liu, Qing Peng
Summary: The size and temperature-dependent thermal transport across a Cu-diamond interface is investigated using non-equilibrium molecular dynamics simulations. Results show that the interfacial thermal conductance is proportional to both the system size and ambient temperature. The study provides important insights into the understanding of interfacial thermal transport in Cu-diamond composites and offers a guideline for optimizing their design in experiments.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Physical
Haixia He, Xiaoxi Guo, Yameng Wan, Jingwen Zhang, Xinyu Niu, Ruiai Wang, Qing Liu
Summary: This study investigates the dissolution characteristics of guanidine hydrochloride in organic solvents using experimental and simulation methods. The thermodynamic features of the dissolution process are evaluated through the analysis of enthalpy change, entropy change, and Gibbs free energy change.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Thermodynamics
Irina A. Graur, Marina A. Batueva, Moritz Wolf, Elizaveta Ya. Gatapova
Summary: This article conducts numerical simulations of monatomic vapor condensation on its liquid phase using three different methods. The results show good agreement among these methods for monatomic gases. The Moment Method is found to have great potential for efficient estimation of condensation fluxes while respecting the conservation of mass, momentum, and energy. The study also discusses the presence and effects of an inverted temperature gradient during the condensation process, and proposes a methodology for extracting the condensation coefficient based on the Moment Method results.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Feng Liu, Yuan Zhu, Ruoyu Wu, Rui Zou, Shengbing Zhou, Huiming Ning, Ning Hu, Cheng Yan
Summary: This study explored the interfacial thermal energy transport ability of graphene/hexagonal boron nitride heterostructure with different symmetric tilt grain boundaries at the interface using molecular dynamics simulations. The effects of tilt angle and interface atomic connection type on the interfacial thermal conductance were considered. The results showed that the symmetric tilt grain boundaries reduced the interfacial thermal conductance of the heterostructure by decreasing the overlap of in-plane phonon density of states of atoms near the interface. It was also observed that Model II had superior interfacial thermal energy transport ability compared to Model I, with little influence of symmetric tilt grain boundaries on the interfacial thermal conductance at large tilt angles.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Chemical
Jianhua Guo, Niping Ma, Jiale Chen, Ning Wei
Summary: We used all-atom molecular dynamics simulations to investigate the interfacial thermal conductance of silicon and polymer at different adhesion void ratios. Our results show a linear relationship between interfacial thermal conductance and effective contact area at different temperatures, which can serve as an indicator of interfacial adhesion state. Additionally, we can identify the location of bubbles on the adhesive surface by observing the non-uniformity of surface temperature evolution, reflecting the bonding state of the interface. This study presents a new approach and research framework for non-destructive and rapid testing of adhesion processes.
Article
Thermodynamics
O. Farzadian, F. Yousefi, C. Spitas, K. Kostas
Summary: In this study, non-equilibrium molecular dynamics simulations were used to investigate phonon heat transport in a two-dimensional superlattice with equal-sized domains of graphene and phagraphene. It was found that the minimum thermal conductivity occurred at a superlattice period of 12.85 nm for ribbons, with a value of 155 W/mK. The minimum thermal conductivity of graphene-phagraphene superlattices is approximately 5% of pure graphene thermal conductivity and 50% of phagraphene thermal conductivity.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Shahin Mohammad Nejad, Rajat Srivastava, Francesco Maria Bellussi, Hernan Chavez Thielemann, Pietro Asinari, Matteo Fasano
Summary: The thermal properties of carbon nanotubes/epoxy composites are influenced by heat transfer mechanisms occurring at multiple scales, resulting in a complex relationship between effective thermal conductivity and microscopic characteristics. By studying the thermal properties of individual components and interfaces at the nanoscale, it is found that the effective thermal conductivity of the composite increases with factors such as nanotube length, volume fraction, epoxy curing degree, and system temperature. The approach presented in this study could be applied to investigate other materials or properties in nanocomposites.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Chemistry, Physical
Juan D. Olarte-Plata, Fernando Bresme
Summary: Non-equilibrium molecular dynamics simulations have shown the importance of interfacial degrees of freedom and the limitations of traditional methods when investigating interfacial thermal transport. Using explicit hot and cold thermostats in simulations can significantly impact the calculated interfacial thermal conductance, with short damping times leading to a significant increase in ITC. Additionally, the choice of thermostats can also affect the results, with global canonical velocity rescale thermostats providing independent ITC values but breaking equipartition for Drude particles.
MOLECULAR SIMULATION
(2022)
Article
Construction & Building Technology
R. E. Jones, J. M. Rimsza, J. E. Trageser, J. R. Hogancamp
Summary: Modeling the degradation of cement-based infrastructure due to aqueous environmental conditions is challenging, especially predicting failure. A chemomechanical model was created to study the effects of long-term water exposure on cement paste, incorporating mechanical balance, transport, fracture, and failure. Sensitivity analysis highlighted diffusion coefficient, reaction rate, and shrinkage as key factors influencing degradation. The model extension to include multiple reactions, complex fracture patterns, and uncertainties in three dimensions is ongoing.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Multidisciplinary
Reese E. Jones, Michael T. Redle, Hemanth Kolla, Julia A. Plews
Summary: The study presents a minimally invasive method for propagating material property uncertainty to full-field quantities in solid dynamics, enabling the design of complex systems. The method uses an ensemble of solutions to provide the joint probability density function of desired quantities, showcasing model independence and efficiency.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Chemistry, Physical
R. Skelton, R. E. Jones
Summary: Ionogels are hybrid materials formed by impregnating the pore space of a solid matrix with a conducting ionic liquid, serving as self-supporting electrolytes in Li batteries. The mechanical properties of silica ionogels depend on solid fraction, temperature, and pore width, with the solid matrix fraction increasing moduli and strength. Pore size effects vary qualitatively with deformation mode, with narrower pores enhancing elastic modulus under shear and uniaxial compression and strength under shear and tensile stress.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Materials Science, Multidisciplinary
C. D. Spataru, M. D. Witman, R. E. Jones
Summary: In this study, the phase stability and electronic structure of Li-intercalated MoX2 bilayers were investigated, showing that the H phase is more stable at low Li concentration and the critical Li concentration for the T' -> H transition decreases with increasing atomic mass of the chalcogen atom X. The relative free energy of the two phases becomes less sensitive to Li insertion with increasing atomic mass of X.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Mechanics
G. H. Teichert, M. Khalil, C. Alleman, K. Garikipati, R. E. Jones
Summary: This study investigates the impact of internal porosity, surface roughness, and conformity to designed geometry on material performance in metal additive manufacturing. By using a double U-notched specimen, the researchers provide a statistical model of failure probability near stress concentrations, as well as guidance for designs where material defects could lead to unexpected failures.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Chemistry, Physical
R. Skelton, R. E. Jones
Summary: Ionogels are composite materials with unique attributes that make them promising for electrochemical energy storage applications. This study found that the morphology of the confining matrix and solid volume fraction can impact ionic conductivity and Li+ diffusivity. Low-silica ionogels with wide pores generally exhibit the best transport properties at high temperatures.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Materials Science, Ceramics
Jessica M. Rimsza, Scott J. Grutzik, Reese E. Jones
Summary: Silica glass exhibits rate-dependent and irreversible processes during deformation and failure, with stress relaxation causing changes in defect concentration profile near the crack tip, potentially altering its properties in the inelastic region.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Construction & Building Technology
C. E. Torrence, J. E. Trageser, R. E. Jones, J. M. Rimsza
Summary: Understanding the durability and fracture behavior of concrete is crucial for civil infrastructure. The interfacial transition zone (ITZ), which is considered the weakest region in concrete, has a significant impact on the stiffness and strength of concrete. This study simulated the mechanical response and fracture under compression and tension using a meshless numerical method called peridynamics. The results showed strong relationships between the ITZ properties and the effective modulus and yield strength of concrete, providing insight into the influence of the poorly characterized ITZ on concrete properties. The study demonstrated the applicability of peridynamics to concrete systems and offered valuable information for future design decisions.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Engineering, Multidisciplinary
Wyatt Bridgman, Xiaoxuan Zhang, Greg Teichert, Mohammad Khalil, Krishna Garikipati, Reese Jones
Summary: In this study, we use an encoder-decoder convolutional neural network to predict the failure locations of porous metal tension specimens based on their initial porosities. We demonstrate the effectiveness of data- and loss-based regularization methods and use variational inference to provide uncertainties for the predictions. The resulting predicted variances are effective in ranking the most likely failure locations.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
J. N. Fuhg, N. Bouklas, R. E. Jones
Summary: In this study, a tensor-basis neural network model is proposed to accurately predict the mechanical response of materials, especially those with microstructure and anisotropy. Classical representation theory, novel neural network layers, and L1 regularization are utilized to construct the model.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)
Article
Materials Science, Ceramics
Jessica M. Rimsza, Reese E. Jones
Summary: Reactive classical molecular dynamics simulations were used to analyze the fracture mechanisms at the molecular scale in sodium silicate glasses. The study found a correlation between crack propagation and energy dissipation, with systems exhibiting higher crack propagation showing less energy dissipation. The high sodium mobility near the crack tip enables energy dissipation without requiring the formation of structural defects.
INTERNATIONAL JOURNAL OF APPLIED GLASS SCIENCE
(2023)
Article
Chemistry, Physical
Michael E. Foster, Ian Kendrick, Sanjeev Mukerjee, Reese Jones
Summary: This study uses DFT to investigate the role of a graphitic layer on Ni0/NiOx nanoparticles in preventing oxidation and reduction processes in the hydrogen evolution reaction (HER) in alkaline electrolytes. The findings provide insights into the mechanism of the graphitic layer in enhancing device performance and stability.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Multidisciplinary Sciences
Jeremy E. Trageser, Chven A. Mitchell, Reese E. Jones, Edward N. Matteo, Jessica M. Rimsza, Laura J. Pyrak-Nolte
Summary: Rock and concrete materials undergo volumetric changes in response to variations in moisture content, resulting in differential shrinkage between mineral compositions. The spatial distribution of clay affects the geometry of crack networks, with distributed clay particles yielding the most complex crack networks and extensive damage. Furthermore, differential shrinkage rates between highly shrinkable clay and a homogeneous matrix control crack formation, growth, coalescence, and distribution during dehydration.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Multidisciplinary
Jan Niklas Fuhg, Craig M. Hamel, Kyle Johnson, Reese Jones, Nikolaos Bouklas
Summary: The development of accurate constitutive models for materials undergoing path-dependent processes remains a challenging task in computational solid mechanics. Data-driven modeling approaches have been proposed to establish stress-evolution laws using machine learning representations. However, these approaches require a large amount of data and do not fully enforce necessary thermodynamic principles. In this work, a hybrid framework is proposed that combines classical phenomenological models and data-driven models to handle different amounts of available data and response complexity.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Materials Science, Ceramics
Jessica M. Rimsza, Reese E. Jones
Summary: During fracture, amorphous oxides undergo irreversible processes, including inelastic and nonrecoverable relaxation effects. This study used molecular dynamics simulations to evaluate the inelastic relaxation processes in various amorphous sodium silicate compositions. The results showed that the composition with 20% Na2O-SiO2 exhibited the highest degree of inelastic relaxation, followed by the compositions with 15% Na2O-SiO2, 25% Na2O-SiO2, and finally 10% (NS10) and 30% (NS30) Na2O-SiO2.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
