Article
Mechanics
Sara Moghtadernejad, Mehdi Jadidi, Jack Hanson, Zachary Johnson
Summary: An experimental study investigates the impact of tangential velocity on the dynamics of a water droplet on a spinning superhydrophobic surface. The results show that increasing tangential velocity causes the droplet to spread asymmetrically. Three behaviors are observed depending on impact and tangential velocities: bouncing, symmetrical splashing, and asymmetrical splashing.
Article
Chemistry, Physical
Hiroyuki Kitahata, Yuki Koyano, Richard J. G. Loffler, Jerzy Gorecki
Summary: The motion of a self-propelled rectangular object inside a circular water chamber is studied in this article. A mathematical model is developed to describe the motion, including equations for the orientation and location of the rectangle, as well as a reaction-diffusion equation for the time evolution of the surface concentration of active molecules. Numerical simulations and experiments are conducted to investigate the effects of different supply rates on the motion behavior, revealing various types of motion such as resting at the chamber center, reciprocal motion passing through the center, and star-polygonal motion.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Mechanics
Haojie Xu, Junfeng Wang, Kai Yu, Bin Li, Wei Zhang, Lei Zuo, Hyoung-Bum Kim
Summary: This study investigated the effects of an electric field on droplet impact behavior and dynamic mechanisms. It was found that different impact phenomena occur in different thermal regimes due to the competition between electrostatic and capillary pressures.
Article
Chemistry, Physical
Ishant Tiwari, Swanith Upadhye, V. S. Akella, P. Parmananda
Summary: The study examines avalanche dynamics in an ensemble of self-propelled camphor boats, revealing bursts of activity triggered by stochastic fluctuations in the autonomous state. By using periodic air perturbations on the water's surface, the system can be entrained and the quality of entrainment is optimized at a specific frequency near the Fourier spectrum peak of the ensemble's average speed, hinting at the presence of a deterministic component in the motion bursts.
Article
Mechanics
Lei Xing, Shuai Guan, Minghu Jiang, Longlong Shi
Summary: In this study, the directional transportation of droplets on a surface with controllable wettability was investigated numerically. The mechanisms of directional migration and morphological evolution of droplets impacting on the superhydrophobic-hydrophobic interface were revealed, and the effects of the impacting position on the migration velocity, rebound height, and transport distance of droplets were analyzed. Theoretical models were derived for predicting the transport distance and rebound height of droplets. The simulation results showed different stages in the process of droplet impacting on the superhydrophobic-hydrophobic interface compared to a normal surface. The study also found the existence of an optimal adhesion length for maximizing the transport distance of the droplet. The results contribute to the fundamental theory of droplet directional migration and have practical applications.
Article
Green & Sustainable Science & Technology
Zhankui Wang, Yakun Yang, Zhao Zhang, Minghua Pang, Mingchao Liang, Lijie Ma, Jianxiu Su
Summary: The dressing effect and dressing quality of the fixed abrasive lapping pad can be improved by using abrasive water jet technology, which has good results in removing coppers from the pad's surface. The influence of jet pressure, nozzle target distance, abrasive concentration, and injection angle were discussed, and it was found that these factors are related to the residual height of the lapping pad surface after dressing.
INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING-GREEN TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
Benjamin Reichert, Jean-Benoit Le Cam, Arnaud Saint-Jalmes, Giuseppe Pucci
Summary: The study demonstrates the self-propulsion mechanism of a volatile drop on the surface of an immiscible liquid through the conversion of evaporative heat pumping into directed motion. The propulsive force is generated by convection-sustained temperature gradients along the drop interface, leading to the advection of a warmer pool of liquid by the hydrodynamic flow in the underlying bath toward the back of the drop. The dependence of the drop speed on the evaporation flux is derived and experimentally validated.
PHYSICAL REVIEW LETTERS
(2021)
Article
Mechanics
Zhengkai Gu, Yuhe Shang, Dong Li, Fanbiao Ai, Hao Zhou, Peng Yuan
Summary: The study demonstrates that the contact time of a droplet impacting on a superhydrophobic substrate can be reduced by adding a macro-wire or a rectangular ridge. The asymmetric retraction of the impacting droplet strongly depends on the combined effect of Weber number and the suspended height.
Article
Polymer Science
Pornchai Rachtanapun, Dheerawan Boonyawan, Rafael A. Auras, Gopinath Kasi
Summary: The use of SF6 plasma treatment improves the water resistance of Kraft paper. The optimal treatment conditions are 200 mTorr pressure, 50 Watts power, and 5 minutes treatment time. Increasing the treatment time enhances the contact angle, water absorption time, and Cobb test values of the paper, while the thickness and tensile strength remain relatively constant.
Review
Engineering, Multidisciplinary
Freshteh Sotoudeh, S. Mahmood Mousavi, Nader Karimi, Bok Jik Lee, Javad Abolfazli-Esfahani, Mohammad K. D. Manshadi
Summary: Self-cleaning surfaces, inspired by butterfly wings and lotus leaves, have various industrial applications such as manufacturing solar panels and glass. They can be used for oil-water separation in the petroleum industry, reducing cleaning time and cost while improving durability. Self-cleaning surfaces can be classified as hydrophilic and hydrophobic, with different cleaning mechanisms. Currently, water-repellent surfaces are more commonly used in self-cleaning technologies.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Mechanics
Lijuan Qian, Zongwei Zhou, Chenlin Zhu, Hang Ding
Summary: This study investigates the dynamic behavior of droplet collisions on superhydrophobic cylindrical surfaces. The results show that increasing eccentricity reduces droplet symmetry and spreading factor. Two collision modes, asymmetric stretching and stretched rebound, are observed. Increasing eccentricity leads to a transition from stretching to bouncing, resulting in reduced contact time during eccentric impact.
Article
Engineering, Mechanical
Lakshminarayana Reddy Tamatam, Daniele Botto, Stefano Zucca
Summary: This paper investigates the effect of wear on the dynamics of the shrouded bladed disk, focusing on the frictional contacts at the shrouds and the contact interface evolution. The study shows the impact of wear on the steady-state nonlinear dynamic response using a coupled approach.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Chemistry, Physical
Satoshi Nakata, Masaki Yoshikai, You Gunjima, Masao Fujiwara
Summary: This study investigates the behavior of self-propelled objects on a field without boundary by placing camphor disks on a levitated water droplet under microgravity. The research demonstrates the synchronized motion and unidirectional rotation of the camphor disks, and suggests that self-propelled objects can exhibit cooperative motion in such a field.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Mechanics
Taehyun Kim, Donghyun Kim, Daegyoum Kim
Summary: This study experimentally investigated the impact force during water entry of a flat disk with a surface pattern. The trapped air inside the patterned disk played a cushioning effect, leading to a decrease in the peak impact force and an extension in the period of impact force fluctuations. The impulse exerted on the disk remained similar regardless of the total volume of holes and the pattern.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Shuai Chen, Zhi Zhang, Yu Zhang, Yong Sha
Summary: A three-dimensional multiphase numerical model is used to simulate the motion and force change of a Marangoni self-driven object. The study also investigates the impact of Marangoni convection on the object's motion.
Article
Chemistry, Physical
Muneyuki Matsuo, Katsunari Yasuda, Kei Nishi, Masakazu Kuze, Hiroyuki Kitahata, Yasumasa Nishiura, Satoshi Nakata
Summary: The Belousov-Zhabotinsky (BZ) reaction was used to study the determination of traveling waves (TWs) direction in a spherical field. Experimentally, TWs were generated at the contact point between a cation-exchange resin bead loaded with the catalyst and a glass plate with lower density silicone grease, and at the upper half of the bead for a higher density silicone grease. Numerical calculations qualitatively reproduced these results. Adsorption of Br2 into the silicone grease is discussed as the source of the inhibitor.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Hiromi Hashishita, Shinpei Tanaka, Satoshi Nakata, Muneyuki Matsuo
Summary: Subsequent synthesis and detection using droplets as microreactors enable small-scale synthesis and detection of covalent/non-covalent intermolecular interactions. The self-organization of autonomous droplets under non-equilibrium conditions is beneficial for manipulating the sequentiality and selectivity of droplet coalescence. Sequentially selective coalescence of non-identical self-propelled droplets was demonstrated based on their collective motion, promoting a new type of powerful and efficient automation technology.
Article
Chemistry, Multidisciplinary
Brigitta Duzs, Gabor Hollo, Hiroyuki Kitahata, Elliott Ginder, Nobuhiko J. Suematsu, Istvan Lagzi, Istvan Szalai
Summary: Turing instability is a general mechanism of pattern formation in reaction-diffusion systems, which has been observed in various biological phenomena. However, the robustness of the Turing mechanism remains uncertain. This study investigates the effect of sinusoidal variation of input feed concentrations on chemical Turing patterns, and demonstrates that patterns can still emerge even with significant amplitude variation. Moreover, time-dependent feeding can be used to control pattern formation, leading to the disappearance of settled patterns or the emergence of new patterns from a homogeneous steady state.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Tomoya Kojima, Hiroyuki Kitahata, Kouichi Asakura, Taisuke Banno
Summary: This study reports on the collective motion and pattern formation of oil droplets in surfactant solutions induced by the conversion of photoresponsive surfactants. The photoisomerization of surfactants generates a gradient of interfacial tension, leading to specific flow fields around the droplets. This research is helpful in understanding the mechanism of life motion from a physicochemical perspective.
CELL REPORTS PHYSICAL SCIENCE
(2023)
Article
Cell Biology
Keisuke Imafuku, Hiroaki Iwata, Ken Natsuga, Makoto Okumura, Yasuaki Kobayashi, Hiroyuki Kitahata, Akiharu Kubo, Masaharu Nagayama, Hideyuki Ujiie
Summary: This study found that epithelial turnover and proliferation are associated with the distribution of ZO-1 in squamous epithelia. Comparisons between normal skin and psoriasis, as well as buccal mucosa and oral lichen planus, revealed that slower cell turnover/proliferation leads to confinement of ZO-1 to the uppermost part of squamous epithelia, while faster cell turnover/proliferation results in wider distribution of ZO-1.
CELL PROLIFERATION
(2023)
Article
Physics, Multidisciplinary
Hiroyuki Kitahata, Alexander S. Mikhailov
Summary: A novel mechanism of reaction-induced active molecular motion, not involving any kind of self-propulsion, is proposed and analyzed. The conformational transitions in mechano-chemical enzymes are accompanied by motions of their centers of mass due to the momentum exchange with the surrounding solvent. This phenomenon, called molecular dancing, can boost the translational diffusion of enzymes and may explain various experimental findings.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Chemistry, Multidisciplinary
Hiroki Sakuta, Naoki Nakatani, Takayuki Torisawa, Yutaka Sumino, Kanta Tsumoto, Kazuhiro Oiwa, Kenichi Yoshikawa
Summary: Water phase separation in cells can lead to mechanical motion by entrapping protein motors and generating vortex flow inside cell-sized droplets. This study reveals that the water phase separation interface can drive translational motion of droplets by spontaneously entrapping kinesins and microtubules and generating vortex flow. The findings highlight the importance of water phase separation in both chemical and mechanical processes.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Physical
Takuya Fujino, Muneyuki Matsuo, Veronique Pimienta, Satoshi Nakata
Summary: The study examined the motion of an organic droplet containing thymol acetate in an aqueous phase, revealing two types of oscillatory motion and attributing the pH-dependent oscillation frequency to the equilibrium between thymol acetate and its ions. The results highlight the possibility of designing self-propulsion systems by considering reaction kinetics and chemical properties.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Multidisciplinary
Maoji Liu, Zhanglin Hou, Hiroyuki Kitahata, Linli He, Shigeyuki Komura
Summary: We numerically investigate the phase separation dynamics of the non-reciprocal Allen-Cahn model in which two non-conserved order parameters are coupled. The system exhibits several dynamical patterns such as the randomly oscillating phase and the spiral phase as well as the homogeneously oscillating phase. Topological defects in the spirals are either bound or unbound depending on the non-reciprocality. The traveling stripe pattern is also found when the diffusion constants are highly asymmetric and the non-reciprocality is small.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Chemistry, Physical
Richard J. G. Loffler, Tomasz Rolinski, Hiroyuki Kitahata, Yuki Koyano, Jerzy Gorecki
Summary: We discuss the motion of a rectangular camphor boat, examining the effect of the position of a camphor pill on the boat's stern. The boat moves due to the release of surface active molecules by the pill, which decreases surface tension and facilitates motion. We introduce a new experimental setup where the boat rotates on a long arm in a Petri dish, allowing for the observation of different motion modes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Risa Fujita, Nami Takayama, Muneyuki Matsuo, Makoto Iima, Satoshi Nakata
Summary: The research team has developed a self-propelled object consisting of a plastic cup and a camphor disk to exhibit its three-dimensional shape in motion on water. The motion of the object, driven by the difference in surface tension, shows oscillatory motion between motion and rest. The period and maximum speed of oscillatory motion are influenced by the cup height, h. Diffusion coefficients were estimated based on the diffusion of camphor molecules visualized indirectly using 7-hydroxycoumarin. The experimental results suggest that the three-dimensional shape of an object can create characteristic features of motion.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Yujin Kubodera, Yu Xu, Yuta Yamaguchi, Muneyuki Matsuo, Masashi Fujii, Maya Kageyama, Oliver Steinbock, Satoshi Nakata
Summary: Chemical gardens formed from two metal salts (MCl2 or MSO4) were studied to understand the impact of mixing on the growth of precipitate tubes. Depending on the combination of the metal salts, tube growth can be classified into collaborative, inhibited, and individual growth. The characteristics of tube growth were discussed in relation to flow near the tube tip controlled by osmotic pressure and solubility product, K-sp, for M(OH)(2). This study can be seen as an inanimate model system for symbiosis among different species, such as mixed cropping systems and survival among different types of microbial cells.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Nana Takeda, Hiroaki Ito, Hiroyuki Kitahata
Summary: A fluid system called the density oscillator is studied, which exhibits oscillatory flow between fluids of different densities through connecting pores. The synchronization behavior in coupled density oscillators is investigated using two-dimensional hydrodynamic simulation, and the stability of the synchronous states is analyzed based on phase reduction theory. The results reveal that antiphase, three-phase, and 2-2 partial-in-phase synchronization modes can spontaneously arise as stable states in two, three, and four coupled oscillators, respectively. The phase dynamics of coupled density oscillators are interpreted with the sufficiently large first Fourier components of the phase coupling function.
Article
Chemistry, Physical
Hiroyuki Kitahata, Yuki Koyano, Richard J. G. Loffler, Jerzy Gorecki
Summary: The motion of a self-propelled rectangular object inside a circular water chamber is studied in this article. A mathematical model is developed to describe the motion, including equations for the orientation and location of the rectangle, as well as a reaction-diffusion equation for the time evolution of the surface concentration of active molecules. Numerical simulations and experiments are conducted to investigate the effects of different supply rates on the motion behavior, revealing various types of motion such as resting at the chamber center, reciprocal motion passing through the center, and star-polygonal motion.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Correction
Chemistry, Physical
Chen Luo, Yan Shao, Hua Yu, Hong-zhi Ma, Yu-hao Zhang, Long Gu, Bo Yin, Ming-bo Yang
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Stefano Borocci, Armando Camerlingo, Felice Grandinetti, Maria Rutigliano, Nico Sanna
Summary: The complexes of He, Ne, Ar, Kr, and Xe with B3N3H6 were investigated using MP2, CCSD(T), and SAPT ab initio methods. The complexes can be described as mono-, di-, and tri-coordinated to the N atoms, with stability following the order N-mono < N-di < N-tri. The interactions are dominated by dispersion and the binding energies are within the range of 1 or 2 kcal mol(-1). The results were compared with a recent DFT study on larger BN sheets complexes [Phys. Chem. Chem. Phys. 24 (2022) 2554-2566.].
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
V. Nagarajan, R. Bhuvaneswari, R. Chandiramouli
Summary: In this study, stable phosphoborane was used as a sensor to detect isobutane and n-propane in Liquefied Petroleum Gas (LPG). Phosphoborane demonstrated structural stability and semiconducting nature, and exhibited promising adsorption properties for the LPG molecules.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Xiaoxi Xu, Zijiang Yang, Bayaer Buren, Maodu Chen
Summary: In this study, the time-dependent wave packet method was used to investigate the reaction channels and mechanisms of Ca+ + HD. The results show that the CaH+ + D reaction channel plays a primary role, which is consistent with experimental results. Complex forming and direct-abstraction reaction mechanisms exist in this reaction process.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Keshab Pandey, Hae Kyung Jeong
Summary: A free-standing silicon-carbon nanofiber composite film was synthesized and investigated for supercapacitor applications. It exhibited high specific capacitance, energy density, and power density. After 5000 cycles, the film showed excellent specific capacitance retention and Coulombic efficiency.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Xinyu Zhang, Haosong Li, Xiaoyu Cao, Jing Gao, Yong Wei, Jianzhuo Zhu
Summary: The evaporation behavior of nanosized water aggregations on two-dimensional electroneutral solid surfaces with different surface polar unit densities was investigated. The results showed that the evaporation rate changes non-monotonically with the surface polar unit density, and the minimum evaporation rate is obtained when the surface has a modest surface polar unit ratio of 66.7%.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Yanyan Xu, Rui Dai, Xiaojie Wang, Zhijun Qiao, Haowei Wen, Dianbo Ruan, Yuzuo Wang
Summary: This article presents an innovative solvothermal sodium insertion method for synthesizing Triphylite-NaFePO4, which demonstrates optimal electrochemical performance in sodium-ion batteries.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Meiyi Jiang, Kun Yang, Yancheng Liu, Li Yao
Summary: The geometric structure and electronic properties of transition metal M (M = Cu, Fe, Mn)-TiO2 (101) surface adsorbed by NO2 and N2O were calculated by density functional theory (DFT) and DFT + U theory. The results showed that the adsorption of NO2 and N2O on Mn and Fe atoms is more stable, and a large number of active electrons are formed around these atoms, facilitating the catalytic reactions.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Sergey A. Vyrko, Yulia G. Polynskaya, Nikita A. Matsokin, Andrey M. Popov, Andrey A. Knizhnik, Nikolai A. Poklonski, Yurii E. Lozovik
Summary: In this study, carbon nanobracelets, which are cyclic molecules composed of alternating polycyclic regions and double carbon chains, were investigated using spin-polarized density functional theory. The results show that carbon nanobracelets with odd number of monomers exhibit distinct electronic energy levels, band gaps, and carbon chain deformation compared to those with even number of monomers.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Chanchan Wang, Quan Yang, Yanzhi Ding, Xiaoyong Lu, Dong Tian
Summary: It has been found that the introduction of buffer layers improves the electrical performance of solid oxide fuel cells (SSOFCs). In this study, varying ratios of Gd-doped CeO2 were used as buffer layers in YSZ-based SSOFCs. The results demonstrate that the performance of SSOFCs is enhanced when a buffer layer is added, with the highest performance achieved using Ce0.8Gd0.2O2-delta (GDC20) as the buffer layer. This suggests that the use of GDC series buffer layers is an attractive strategy to optimize performance loss due to electrolyte-electrode interactions.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Wang Li, Yi-Fan Zhang, Jia-Bin Huang, Chang-Yang Wang, Feng Zhang, Jiu-Zhong Yang, Long Zhao
Summary: The gas-phase reaction of propargyl with vinylacetylene was investigated using synchrotron photoionization and molecular-beam mass spectrometry methodologies. The formation mechanisms of the resulting cyclic structures were examined using quantum computations. Two previously unidentified isomers were detected and identified for the first time.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Avijit Pramanik, Sanchita Kundu, Olorunsola Praise Kolawole, Kaelin Gates, Paresh Chandra Ray
Summary: This study investigates the influence of aspect ratio and quantum confinement on the single-photon and two-photon absorption cross-section of perovskite CsPbI3 nanorods. Experimental data shows that CsPbI3 nanorods have an extremely high two-photon absorption cross-section, significantly surpassing organic chromophores and other CsPbBr3 nanocrystals. Moreover, adjusting the aspect ratio can significantly enhance the absorption ability. Additionally, the study also reveals a moderate quantum confinement effect on the single-photon and two-photon absorption cross-section of the nanorods.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Hyon-Tae Pak, Jin-A Choe, Kyong-Sik Ju, Yong -Son Rim
Summary: Drug-loaded cellulose diacetate (CDA) membranes were prepared using different compositions of mixed solvent. The microstructure and performance of the membranes were investigated, and a method to predict drug release properties was proposed. The results showed that the composition of the mixed solvent significantly affected the overall performance of CDA membranes, and the release rates of drugs were related to Δdelta and the intrinsic viscosity of CDA.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Gabriella E. Ravin, E. Curotto
Summary: We have developed a systematic approach to optimize the training set sizes for neural networks in fitting ab initio potential energy surfaces. Using this approach, we have constructed several spectroscopic quality potential energy surfaces for [Li(H2)n]+, n = 1 - 9. The ground state properties have been computed for all the systems and selected states.
CHEMICAL PHYSICS LETTERS
(2024)
Article
Chemistry, Physical
Guohua Xu, Lei Xu, Feng Zhang, Chunling Yu, Yu Song
Summary: NiS1.03@Ni7S6/carbon composite was successfully prepared using corn stalk as a carbon source via a simple adsorption-sulphurization process. The composite exhibited a specific capacitance of 1554.6 F/g at 1 A/g as a supercapacitor electrode, with a capacitance retention rate of 80.4% after 5000 cycles. Furthermore, the NiS1.03@Ni7S6/carbon//AC asymmetric supercapacitor showed a high energy density of 41.2 Wh kg-1 at a power density of 750 W kg-1, and excellent cycling stability with 86.8% capacitance retention after 10,000 cycles.
CHEMICAL PHYSICS LETTERS
(2024)
