Article
Chemistry, Multidisciplinary
Yaxu Zhong, Vincent R. Allen, Jun Chen, Yi Wang, Xingchen Ye
Summary: Using in situ electron microscopy, the researchers observed the self-assembly pathway of nanoparticles into ordered superlattices. The study provides insights into the crystallization process and the interactions between nanoparticles.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Jingqun Liu, Chaohui Wang, Yujing Chen, Qiaofeng Lan
Summary: Despite extensive efforts in studying polymer crystallization, the microscopic mechanisms of crystal nucleation are still not well understood. In this study, the crystal nucleation of poly(L-lactide) under high supercooling was investigated using various techniques. The results revealed a multi-step nucleation pathway involving the formation of metastable intermediate phases. These intermediate phases possessed distinct intermediate orders and gradually transformed into the nascent crystalline phase. The findings provide insights into the crystal nucleation mechanisms under large supercooling and have implications for understanding the crystallization of synthetic polymers.
ACS APPLIED POLYMER MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Gan Wang, Hwee Ting Ang, Srinivas Reddy Dubbaka, Patrick O'Neill, Jie Wu
Summary: The automation of pharmaceutical synthesis has been a long-term goal in the industry, as it allows for rapid and efficient preparation of organic compounds and frees chemists from laborious work. Efforts have been made to improve the universality and capability of automation in multistep synthesis, with a focus on automated iterative synthesis, automated digitalized batch synthesis, automated SPS-flow synthesis, automated radial synthesis, and automated multistep continuous-flow synthesis. This review highlights the recent development of these methods and their complementarity in the automated synthesis of pharmaceuticals.
TRENDS IN CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yuliana Perdomo, Joseph M. Slocik, David M. Phillips, Marc R. Knecht
Summary: The realization of multifunctional nanoparticle systems is crucial for highly efficient catalytic materials in specific applications, but their production remains challenging. While typically achieved through incorporating multiple inorganic components, functionality can also be achieved at the organic ligand layer. In this work, peptide-based ligands were used to generate multifunctional nanoparticle catalysts for tandem catalytic functionality. This study provides a unique pathway to achieve multifunctionality in nanoparticle systems through the incorporation of inorganic and bio/organic components, with potential implications for applications beyond catalysis in areas such as theranostics, sensing, and energy technologies.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Zhuang Shi, Chengkun Liu, Xiaodan Liu, Xiaoqiang Wang, Fang Huang
Summary: By constructing carboxyl-/phosphate-rich biomimetic liposomes, researchers induced the formation of nanometer-sized CaCO3 clusters, which then grew into CaCO3 droplets embedded in liposomes. This study demonstrates a liposome-mediated transition of CaCO3 from clusters to liquid and further to supracolloidal assemblies, suggesting similar heterogeneous processes may occur in natural mineralization.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Chemistry, Multidisciplinary
Nour El Beyrouti, Felix Houard, Marie Cordier, Elzbieta Trzop, Stephane Rigaut, Boris Le Guennic, Kevin Bernot, Lucie Norel
Summary: This article presents a dinuclear metallacycle that is assembled from a bispyridyl dithienylethene linker and a highly anisotropic dysprosium based Single Molecule Magnet (SMM). It exhibits magnetic hysteresis at 1.8 K and photoisomerization in single crystals (SC). The impact of photoswitching on the SMM behavior is evidenced and correlated with the specific organization of the magnetic units.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Masaya Sakakibara, Hiroki Nada, Takayuki Nakamuro, Eiichi Nakamura
Summary: Operando imaging experiments conducted in carbon nanotubes revealed the metastable process of crystal nucleation, with a floating island (FI) identified as the first intermediate on the surface of NaCl crystals undergoing thermal migration. Tumbling of the crystal repeatedly changes the surface energy, promoting the conversion of FI into a new epitaxial layer.
ACS CENTRAL SCIENCE
(2022)
Article
Chemistry, Physical
Ahmed Hafez, Qi Liu, J. Carlos Santamarina
Summary: Self-assembly of millimeter-scale magnetic particles in a bubble-column reactor forms 9 different structures, with two component systems assembling faster than one-component systems. The efficiency of self-assembly is highest at intermediate Mason numbers, where the interplay between hydrodynamic forces and magnetic interactions is optimal. Strategies to improve yield include the use of pre-assembled nucleation templates and engineered boundaries to overcome kinetic traps.
Article
Chemistry, Multidisciplinary
Zhouyang Zhang, Yujie Tang, Yiran Ying, Junqing Guo, Min Gan, Yateng Jiang, Chunxian Xing, Shanshan Pan, Ming Xu, Yangbo Zhou, Haitao Zhang, Chi Wah Leung, Haitao Huang, Chee Leung Mak, Linfeng Fei
Summary: This study provides insights into the nucleation process by observing solid-state nucleation in real time. The findings suggest that early-stage crystallization can follow a non-classical pathway and involve multiple intermediate steps. The driving force for these events is believed to be the energetic favorability.
MATERIALS HORIZONS
(2022)
Article
Chemistry, Multidisciplinary
Wei-Hao Hsu, Ing-Shouh Hwang
Summary: This study used transmission electron microscopy to investigate the microstructure of degassed water, deionized water, and gas-supersaturated water, revealing two major structures in the latter and the surprising discovery of clathrate-like water crystalline structures. The findings suggest that water may play a more active role in interacting with gas molecules than previously thought.
Article
Engineering, Mechanical
Hongfei Wu, Xincun Zhuang, Wen Zhang, Zhen Zhao
Summary: In this study, an anisotropic Gurson-Tvergarrd-Needleman (GTN) model considering anisotropic void behaviors was proposed to accurately predict anisotropic ductile fracture. The effect of high stress triaxiality on void nucleation was considered through an additional stress dependent factor, and anisotropic stress triaxiality was adopted. A new formulation related to anisotropic critical damage was proposed to describe the difference in damage accumulations along different material orientations. Uniaxial tension experiments were performed to validate the proposed model, and remarkable improvement was achieved when considering the contribution of high stress triaxiality, anisotropic void nucleation, and critical damage in the modeling of anisotropic ductile fracture.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Optics
Reuben R. W. Wang, John L. Bohn
Summary: In this paper, we investigate plane wave modes in ultracold, non-quantum degenerate, dipolar Fermi gases under the hydrodynamic limit. Longitudinal waves exhibit anisotropies in both their speed of sound and damping, as well as a small undulatory effect in their flow velocity. Two distinct types of shear waves are observed, one being familiar and the other accompanied by nontrivial density and temperature modulations. We propose using these shear modes as an experimental approach to measure the viscosity coefficients, including their anisotropies.
Article
Chemistry, Physical
Changseop Jeong, Jiyeon Yun, Jiyoung Heo, Nam Joon Kim
Summary: Anisotropic circular dichroism (CD) is observed in oriented molecules, showing variations with the direction of light propagation. This study investigates the anisotropic CD of isolated chiral molecules and suggests that the CD spectra of cold, isolated molecules like those in an interstellar medium may exhibit anisotropic CD values.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Applied
Zhiyuan Yang, Yinyan Li, Wenying Xue, Zhiqiang Yin, Zhuoyue Meng, Anning Zhou
Summary: The study found that the types and contents of small molecules in the extracts decrease with increasing metamorphism. Multi-step solvent extractions of coal increase porosity and remove small organic molecules, impacting the ability of coal to adsorb methane.
Article
Astronomy & Astrophysics
Aleksandra Kuznetsova, Jaehan Bae, Lee Hartmann, Mordecai-Mark Mac Low
Summary: This study explores the impact of anisotropic infall on protostellar disks, showing that it disrupts the disk and triggers the Rossby wave instability, resulting in vortices and spiral waves. These vortices create pressure bumps that impede radial drift of dust grains, leading to the formation of millimeter rings and compact dust disks in the disk.
ASTROPHYSICAL JOURNAL
(2022)
Review
Physics, Multidisciplinary
Jun-ichi Fukuda, Andriy Nych, Uliana Ognysta, Slobodan Zumer, Igor Musevic
Summary: This article reviews the theoretical and experimental studies on the formation of half-Skyrmions in thin films of chiral liquid crystals, demonstrating their existence and highlighting their morphology and optical properties. It emphasizes the use of chiral liquid crystal films as an interesting system for investigating topological concepts and photonics applications.
ANNALEN DER PHYSIK
(2022)
Article
Multidisciplinary Sciences
Hiroto Ozaki, Takeshi Aoyagi
Summary: This paper investigates the prediction of velocity field for multiple fixed cylinders using a deep-learning model, and finds that the accuracy of the prediction is influenced by the number of cylinders. The model accurately predicts the flow when the number of cylinders is close to the training dataset, but shows errors when extrapolating to a smaller number of cylinders, which can be attributed to the internal friction of the fluid.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Multidisciplinary
Hideo Doi, Kazuaki Z. Takahashi, Takeshi Aoyagi
Summary: A combination of atomic numbers and bond-orientational order parameters is considered as a simple representation that involves both atomic species and their positional relation. By performing regression analysis and supervised machine learning on the atomic charges, 60 fingerprints were selected that successfully estimate the atomic charges and other properties, indicating their potential to precisely describe the chemical and structural information of the atomic environment of molecules.
Article
Materials Science, Multidisciplinary
Takeshi Aoyagi
Summary: This study presents the design of polymer structures with desired stress-strain properties using coarse-grained molecular dynamics simulations and artificial neural networks. Through simulation and optimization, a polymer structure that agrees with the predicted curve is obtained, providing an efficient method for material design.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Polymer Science
Takeshi Aoyagi
Summary: This study investigated the elasticity of block copolymers through coarse-grained molecular dynamics simulation. The effects of morphology, bridge fraction, and deformation direction on stress-strain curves were studied. The results showed that glassy networks with the DG morphology had higher initial moduli compared to those with the BCC morphology. The rubber elasticity was linearly dependent on the bridge fraction in BCC morphology, but weakly dependent in DG morphology due to the contribution of loop configurations. The effect of deformation direction was insignificant in both morphologies, contrary to experimental results.
Article
Polymer Science
Haruka Yasuoka, Kazuaki Z. Takahashi, Takeshi Aoyagi
Summary: The crosslink density of liquid crystal elastomers (LCEs) plays a crucial role in the stress-strain curves. As the crosslink density increases, the strain region corresponding to soft elasticity becomes narrower, and the change in the orientation order parameter becomes steeper. Meanwhile, the stress values in the plateau region increase. This indicates a systematic trade-off between stress and strain in the soft elasticity of LCEs.
Review
Chemistry, Physical
Jun-ichi Fukuda
Summary: This article presents numerical studies on the exotic structures of chiral liquid crystals, particularly focusing on those in thin films. The research shows that thin films of chiral liquid crystals can exhibit a diverse variety of ordered structures, including a hexagonal lattice of topological line defects. This provides an interesting platform for investigating exotic structures of orientational order arising from the frustration between bulk ordering and spatial confinement with surface anchoring.
LIQUID CRYSTALS REVIEWS
(2022)
Correction
Chemistry, Physical
Kazuaki Z. Takahashi
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Kazuaki Z. Takahashi
Summary: This study developed a machine learning package called MALIO for quickly and automatically selecting local order parameters (LOPs), uncovering their importance in distinguishing liquid crystal phases and observing phase transitions, and identifying the best-performing LOP species.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Multidisciplinary Sciences
Hideo Doi, Kazuaki Z. Takahashi, Haruka Yasuoka, Jun-ichi Fukuda, Takeshi Aoyagi
Summary: This study focuses on liquid crystal elastomers (LCEs) and aims to identify the design variables of their molecular architectures that govern their macroscopic deformations. Regression analysis using machine learning (ML) is applied to analyze a database of LCE simulations, and a surrogate model is generated to predict stress-strain curves. The results reveal key design variables and demonstrate the predictive potential of the ML scheme in accelerating LCE material exploration.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Multidisciplinary
Kazuaki Z. Z. Takahashi, Masaki Hiratsuka
Summary: This study combines molecular simulation and machine learning to successfully investigate the structural transitions of cyclopropane hydrate and ice. By evaluating and classifying different local order parameters, the optimal set of order parameters that distinguish between different structures is determined.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Polymer Science
Haruka Yasuoka, Kazuaki Z. Takahashi, Takeshi Aoyagi
Summary: Applying electric fields to liquid crystal elastomers (LCEs) is an efficient method for actuating soft robotics, but it is important to determine the minimum electric field strength and reorientation time for optimizing LCE electrical actuation. Molecular dynamics simulations were conducted to study the relaxation behavior of stress and orientational order in LCE systems under an applied electric field. The results showed that the minimum electric field strength and reorientation time differ for main-chain and side-chain LCEs, suggesting the need for careful design of LCEs at the molecular architecture level for precise soft robotics.
Article
Chemistry, Physical
Kazuaki Z. Takahashi
Summary: A strategy was proposed to map PALS measurement data of isotactic polypropylene to CMD simulations, resolving the discrepancy between simulated and experimental glass transition temperatures by shortening polymer chains. The effective probe radius of o-Ps determined by comparing PALS data with CMD simulations was approximately 0.8 nm, consistent with the solution of the Schrodinger equation. Combining PALS measurements with CMD simulations provides insight into cavities in polymeric materials without relying on the WLF equation.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Kenji Katayama, Takuro Yoshimura, Saki Yamashita, Hiroto Teratani, Tomoki Murakami, Hiroaki Suzuki, Jun-ichi Fukuda
Summary: In this study, a new method for controlling topological defects in liquid crystals was proposed and demonstrated. By introducing a liquid layer on the liquid crystal in microwells of a microfluidic device, the liquid/liquid crystal interface can control the alignment and introduce different molecules to form topological defects. The formation and disappearance of topological defects were also shown to be achieved by light illumination, using photo-responsive molecules dissolved in the liquid crystal. This platform has potential for sensor applications.
Article
Physics, Fluids & Plasmas
Akihiro Yamashita, Jun-ichi Fukuda
Summary: We numerically investigate the structure of twin boundaries in cholesteric blue phases. The study shows that the formation of twin boundaries is not prohibitively costly, consistent with previous experimental findings.