Article
Chemistry, Physical
Lei Zhang, Gabor Csanyi, Erik van der Giessen, Francesco Maresca
Summary: Predicting atomistic fracture mechanisms in bcc iron is crucial for understanding its semi-brittle nature. By using a Gaussian approximation potential, we developed a model that accurately predicts critical stress intensity factors for different crack systems. Simulations revealed the mechanism of fracture along the original crack plane for {100} and {110} crack planes.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Mathematics, Applied
Tongmao Li, Peng Liu, Jun Zhang, Xiaofeng Yang
Summary: This work presents a highly efficient numerical scheme for the flow-coupled phase-field model of diblock copolymer melt. By combining a novel decoupling technique and the projection method, an energy stable and second-order time-accurate numerical scheme is developed, only requiring to solve a few elliptic equations at each time step.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2022)
Article
Chemistry, Physical
Bin Chen
Summary: A lattice-based version of the aggregation-volume-bias Monte Carlo method extends the calculation of nucleation free energies from liquid clusters to solid clusters. By using this method, the nucleation free energies of bcc and fcc clusters formed by Lennard-Jones particles were calculated, showing a crossover of thermodynamic stability from bcc to fcc structure. The obtained free energies were used to extrapolate bulk phase information, confirming the preference of bcc clusters due to lower surface tension. This work demonstrates the capability of this approach to predict the entire thermodynamic landscape, which is important for understanding crystallization and polymorphism.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Polymer Science
Dan-Yan Qin, Sheng-Da Zhao, Zhi-Xin Liu, Jing Zhang, Xing-Hua Zhang
Summary: This study presents a novel and concise theoretical approach for solving the conformation statistics of complex polymers based on Monte Carlo and Neural Network method. It offers a new research idea for investigating the conformation statistics, and it can be applied to more complex polymer systems, theory research, and experimental data analysis. The conformation statistics of complex polymers determine the structure and response properties of the system.
CHINESE JOURNAL OF POLYMER SCIENCE
(2023)
Article
Mathematics
Junying Cao, Jun Zhang, Xiaofeng Yang
Summary: In this work, a numerical approach is proposed for the phase-field model of diblock copolymer melt confined in Hele-Shaw cell. The approach decouples the coupled nonlinear system and ensures energy stability by introducing auxiliary variables and auxiliary ordinary differential equations. The proposed scheme is shown to be linear, unconditionally energy stable, and has high implementation efficiency. Numerical experiments verify the convergence rate, energy stability, and effectiveness of the algorithm.
COMMUNICATIONS IN MATHEMATICS AND STATISTICS
(2022)
Article
Physics, Multidisciplinary
Alexander Mietke, Jorn Dunkel
Summary: Researchers studied dihedral (k-atic) liquid crystals (DLCs) by generalizing the half-integer defects in nematic liquid crystals. They developed a unified hydrodynamic description model and investigated its behavior through particle simulations. They also predicted a novel spontaneous chiral symmetry-breaking transition in antialigning DLCs.
Article
Polymer Science
Xinyue Zhang, Mingge Zhao, Junhan Cho
Summary: This paper revisits the phase behaviors of molten A-b-B diblock copolymers with disparity in self dispersion interactions. The authors obtain a free energy functional for corresponding Gaussian copolymers under the influence of effective interactions derived from the localized excess equation of state. They formulate the Landau free energy expansion as a series in powers of A and B density fluctuations and provide an alternative Landau energy through a transformation of the order parameters. The authors show that the cubic term is balanced with Gaussian cubic vertex coefficients to yield a critical point at a composition rich in a component with stronger self interactions.
Article
Physics, Condensed Matter
Yashen Wang, Zun Liang, Xin Zhang, Wenliang Lu, Zhiyong Yu, Xiangming Ma, Hongtao Liang, Yang Yang
Summary: By employing simulations and theoretical analysis, we predicted kinetic coefficients for soft-sphere interfaces and compared them with previous data. We found a universal behavior in these systems and proposed a hypothesis regarding the anisotropic relaxation times of interface melt phases.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Chemistry, Physical
Qinyu Zhu, Timothy R. Scott, Douglas R. Tree
Summary: Researchers have long been interested in biological cells' ability to actively control their shape, leading to the study of generating simplified synthetic protocells that can change shape based on a stimulus. By combining DPD and SRBD, a simulation tool was created to study morphological changes in polymer structures undergoing chemical reactions. It was found that local morphological changes can be induced by solvents or reactants affecting the block polymer chemistry in the membrane.
Article
Polymer Science
Hideaki Takagi, Katsuhiro Yamamoto
Summary: The stability of ordered bicontinuous double-diamond (OBDD) phases in blends of polystyrene-polyisoprene block copolymer (PS-PI) and polyisoprene (PI) was found to be influenced by the block copolymer composition, homopolymer molecular weight, and homopolymer content. The added homopolymer localized in the middle of the microdomains and relieved packing frustration inside the four-fold nodes of OBDD, resulting in a stable OBDD structure.
Article
Chemistry, Physical
Xiaoyuan Wang, Shixin Xu, Fredric S. Cohen, Jiwei Zhang, Yongqiang Cai
Summary: The effect of cholesterol content on biological membranes was studied using a polymer system. The liquid-crystal behavior of certain components was found to strongly influence the chemical potential of cholesterol in bilayer membranes.
Article
Physics, Applied
Wenhua Wu, Dongzhen Wang, Wei Zhai, Jianyuan Wang, Bingbo Wei
Summary: Multiple power ultrasounds were used to investigate the phase transition process of a ternary Al81.5Cu14.7Bi3.8 immiscible alloy. Increasing ultrasonic sources led to the transformation of the liquid phase separation pattern and the evolution of the primary (Al) phase. Numerical simulations showed that increasing ultrasonic beams enhanced transient cavitation and acoustic streaming strength, resulting in a uniform microstructure and improved friction and wear properties.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Jianghao Zhang, Boxuan Lou, Xiaolan Qin, Yinwen Li, Haikuan Yuan, Lijuan Zhang, Xijian Liu, Yan Zhang, Jie Lu
Summary: Biocompatible and biodegradable amphiphilic polymeric micelles were prepared and used as templates for the crystallization of camptothecin. The nanocrystals prepared by this method demonstrated higher crystallinity, narrower particle size distribution, and slower release characteristic compared to conventional methods. Additionally, the release rate of the nanocrystals was influenced by pH.
Article
Chemistry, Physical
Pierre Kawak, Dakota S. Banks, Douglas R. Tree
Summary: This study focuses on the near-equilibrium nucleation behavior of a simple model of a melt, revealing the existence of ordered nematic and crystalline phases in addition to the disordered melt phase. The research indicates that polymer stiffness plays a crucial role in the nucleation process during polymer crystallization.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Jia-Wen Hong, Jung-Hong Chang, Iris Ching-Ya Chang, Ya-Sen Sun
Summary: By studying the phase behavior of substrate-supported films, we found that different nano-domains appear sequentially with increasing PS content, including lamellae, perforated layers, double gyroid, and cylinders. Annealing temperature and film thickness have significant effects on the formation of perforated layers and double gyroids, with lower annealing temperatures favoring a greater fraction of perforated layers in thick films.
Article
Polymer Science
Russell K. W. Spencer, Bart Vorselaars, Mark W. Matsen
MACROMOLECULAR THEORY AND SIMULATIONS
(2017)
Article
Multidisciplinary Sciences
Alice B. Chang, Christopher M. Bates, Byeongdu Lee, Carol M. Garland, Simon C. Jones, Russell K. W. Spencer, Mark W. Matsen, Robert H. Grubbs
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2017)
Article
Chemistry, Physical
Russell K. W. Spencer, Mark W. Matsen
JOURNAL OF CHEMICAL PHYSICS
(2018)
Correction
Polymer Science
Russell K. W. Spencer, Mark W. Matsen
Article
Chemistry, Physical
Russell K. W. Spencer, Mark W. Matsen
JOURNAL OF CHEMICAL PHYSICS
(2018)
Correction
Chemistry, Physical
Russell K. W. Spencer, Mark W. Matsen
JOURNAL OF CHEMICAL PHYSICS
(2018)
Article
Chemistry, Physical
S. Blaber, P. Mahmoudi, R. K. W. Spencer, M. W. Matsen
JOURNAL OF CHEMICAL PHYSICS
(2019)
Article
Chemistry, Physical
Russell K. W. Spencer, Nima Saeidi, Bae-Yeun Ha
JOURNAL OF CHEMICAL PHYSICS
(2020)
Article
Physics, Multidisciplinary
Bart Vorselaars, Russell K. W. Spencer, Mark W. Matsen
PHYSICAL REVIEW LETTERS
(2020)
Article
Polymer Science
Russell K. W. Spencer, Mark W. Matsen
Summary: This study validates previous predictions through simulations, demonstrating the three-phase coexistence between BEE and two homopolymer-rich phases, and improving the accuracy of the previous phase diagram.
Article
Polymer Science
Russell K. W. Spencer, Bae-Yeun Ha
Summary: Inclusions in a brush disrupt the brush structure and introduce effective particle-particle interactions mediated by the brush. The brush promotes clustering of inclusions when the grafting point is mobile, while inclusions tend to be dispersed when the grafting point is fixed. These findings have biological implications for interactions between antimicrobial peptides and bacterial lipopolysaccharides, as well as clustering of integrin on cancerous cell membranes.
Article
Polymer Science
Russell K. W. Spencer, Mark W. Matsen
Summary: Monte Carlo simulations were used to investigate the surface properties of athermal blends of stiff and flexible polymers as the bending modulus of the stiff polymers increased. Surface transitions occurred twice when hard walls were present, while soft boundaries caused the loss of surface transitions.
Article
Polymer Science
Russell K. W. Spencer, Mark W. Matsen
Summary: In this study, we critically reassessed off-lattice Monte Carlo simulations of athermal blends of stiff and flexible polymers next to a hard wall. Our improved simulations show that the flexible polymers actually have a long-range surface preference, contradicting the original simulations, experiments, and alternative calculations. This resolves a long-standing controversy and supports the predictions of mean-field theory regarding the concentration profile of the flexible polymer.
Article
Chemistry, Physical
Russell K. W. Spencer, Bae-Yeun Ha, Nima Saeidi
Summary: Many macromolecules in both biological and technological fields are chiral and semi-flexible. This study presents a method to study the formation of chiral nematic phases, offering a new approach to understanding the behavior of semi-flexible chiral-nematic polymers.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Russell K. W. Spencer, Bae-Yeun Ha, Nima Saeidi
Summary: This study presents a self-consistent field theory (SCFT) of chiral-nematic polymers, taking into account polymer flexibility and the orientational degrees of freedom. A phase diagram is constructed, showing the regions of stability for isotropic, nematic, and cholesteric phases. Furthermore, it is discovered that nematic interactions can stabilize the cholesteric phase.