Article
Mechanics
Pavan Kumar Singeetham, K. V. S. Chaithanya, Sumesh P. Thampi
Summary: This study focuses on the flow characteristics and deformation dynamics of compound particles in microfluidic devices, revealing that under conditions of low Reynolds number and low Capillary number, the velocity and pressure fields are analyzed for compound particles in linear flow, along with the deformed shape of the confining drop.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Enzo d'Ambrosio, Donald L. Koch, Sarah Hormozi
Summary: Experimental measurements were carried out to investigate the effect of particle shape on the rheology of a dense, viscous suspension. The results showed that both spherical particles and particles with flattened faces exhibited shear thinning behavior, with the latter showing a stronger effect. The resistance to particle rolling was found to be enhanced by the flattened faces, leading to a higher viscosity at low shear stress in the suspension of particles with flattened faces compared to the suspension of spherical particles.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Chemical
Jophous Mugabi, Jae-Ho Jeong
Summary: The dispersed phase volume fraction of concentrated emulsions can be substantially increased without an increase in viscosity by optimizing the droplet-size distribution. However, the traditional methods to control the DSD have limitations, hampering the study of its effect on emulsion mixtures' viscosity. This study used premix membrane emulsification to prepare droplet-size-controlled concentrated emulsions and investigated the effect of DSD on the viscous behavior of emulsion mixtures. It was found that widening the DSD led to decreased viscosity at lower shear rates, but shear-thickening behavior at higher shear rates.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Mechanics
Brato Chakrabarti, Yanan Liu, Olivia du Roure, Anke Lindner, David Saintillan
Summary: Numerical simulations are used to uncover the effects of morphological transitions on the steady shear rheology of a dilute suspension of stiff polymers as they tumble in shear flow. The results are in agreement with classic scalings for Brownian rods in relatively weak flows but differ above the buckling threshold, showing enhanced shear thinning and an increase in normal stress differences. The study highlights the subtle role of thermal fluctuations in triggering instabilities, based on past work on rigid Brownian rods and non-Brownian elastic fibers.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Yuki Matsuoka, Yasuya Nakayama, Toshihisa Kajiwara
Summary: The study focuses on the quantitative prediction of shear thickening in suspensions in viscoelastic fluids, using numerical simulations that align with recent experimental results. The accurate estimation of the first normal stress difference of the matrix is crucial for predicting the shear thickening behavior in a Boger fluid matrix.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Fluids & Plasmas
Kyongok Kang, Alexey Eremin
Summary: This study focuses on the effects of solvents on the self-assembly morphology, microscopic dynamics, and nonlinear optical response of cellulose nanocrystals (CNCs). It is found that the solvents significantly impact the structure and behavior of CNCs, which is important for the design and application of biomaterials.
Article
Mechanics
B. Vowinckel, E. Biegert, E. Meiburg, P. Aussillous, E. Guazzelli
Summary: By comparing simulation data with experimental data, we have identified the rheological behavior of sheared sediment beds in pressure-driven flow and discovered good agreement in rheological properties between dense and dilute regimes. A critical particle volume fraction of 0.3 was found to separate the two regions and the effective viscosity obeyed the Einstein relation in the dilute regime.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Multidisciplinary
Mohammad Nabizadeh, Abhinendra Singh, Safa Jamali
Summary: This study compares force network formation in continuous and discontinuous shear thickening dense suspensions, revealing notable differences in their characteristics and impact on system behavior.
PHYSICAL REVIEW LETTERS
(2022)
Article
Mechanics
Peifeng Lin, Rui Wang, Xiao Hu, Zuchao Zhu, Chenlin Zhu
Summary: Experimental research was conducted to investigate the shear-thinning and strain-stiffening behavior of a bidisperse non-colloidal suspension under steady-state shear and oscillatory shear. The results showed the presence of a second shear-thinning behavior when the volume fraction of the particle suspension was between medium and high. The viscosity exhibited a significant particle size dependence at low shear rates, while the dependence became almost nonexistent at high shear rates. Furthermore, the addition of a surfactant of specific concentration confirmed the influence of microstructural changes on the rheological properties of the suspension.
Article
Materials Science, Ceramics
Zeyu Zhao, Minda Zou, Hua Huang, Ximei Zhai, Harrison Wofford, Jianhua Tong
Summary: One-pot synthesized twin perovskite oxide composite of BaCe0.5Fe0.5O3-delta (BCF) exhibits triple-conducting properties for solid oxide electrochemical cells and shows promising application potential under different conditions.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Mechanics
Enzo d'Ambrosio, Frederic Blanc, Elisabeth Lemaire
Summary: The normal and shear viscosities of non-Brownian suspensions were measured using optical suspension imaging. Two suspensions with different refractive indexes were studied, one density-matched and the other negatively buoyant. The shear viscosity decreases with shear stress and the third particle normal stress is proportional to shear stress. The results are in agreement with previous studies and are discussed in the context of mu(J) rheology.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
James T. Jenkins, Ryohei Seto, Luigi La Ragione
Summary: The study analyzes the extensional flows of a dense layer of spheres in a viscous fluid by using force and torque balances to determine the trajectory of particle pairs. It investigates the relationship between stress, microstructure, and strain rate, and shows that this relation involves the second and fourth moments of the particle distribution function.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Othmane Aouane, Andrea Scagliarini, Jens Harting
Summary: The study investigates the rheology of strain-hardening spherical capsules under confined shear flow through numerical simulations, revealing the significant impact of membrane inextensibility on rheology and the ability to suppress shear-thinning. Furthermore, a non-monotonic relationship between normal stress differences and membrane inextensibility is observed in concentrated suspensions.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
T. Ishikawa, D. R. Brumley, T. J. Pedley
Summary: A computational study comparing Stokesian dynamics and lubrication theory for vertically aligned, identical spherical squirmers subjected to a linear shear flow reveals that viscosity and normal stress differences can vary significantly with parameters such as bottom-heaviness, angle of flow, and squirming parameter. The study also shows that despite different assumptions, the two computation methods give similar results for viscosity in a certain range, suggesting that lubrication theory captures most of the relevant physics for this system.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Phani Kanth Sanagavarapu, Ganesh Subramanian, Prabhu R. Nott
Summary: This paper examines the shape dynamics of deformable elastic and viscoelastic particles in a Newtonian fluid under simple shear. It presents a method to determine the shape dynamics of initially ellipsoidal particles and explores the different dynamics exhibited by various particle shapes. The study also analyzes the effects of different parameters on the particle dynamics.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Applied
Sota Takagi, Koji Inukai, Nobuaki Kawai, Shunsuke Nozawa, Atsushi Kyono, Ryo Fukaya, Shin-ichi Adachi, Kouhei Ichiyanagi
Summary: The study reveals the behavior of transformation-toughened materials under dynamic loading, emphasizing the relationship between crystal structure transformations and dynamic fracture, providing an explanation for the high spall strength of zirconia ceramics, and demonstrating the great potential of the time-resolved x-ray diffraction method in studying fracture dynamics.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Woosuck Shin, Akihiro Tsuruta, Toshio Itoh, Takafumi Akamatsu, Ichiro Terasaki
Summary: The high-temperature conductivity of perovskite oxides in LBCO thin films was studied by RF sputtering and thermal annealing. The conductivity varied depending on the substrate material and deposition process, with Co substitution for Cu resulting in increased conductivity and reduced temperature dependence. Transport properties were investigated to understand carrier generation mechanisms in LBCO films.
Article
Chemistry, Multidisciplinary
Kyusung Kim, Pil Gyu Choi, Toshio Itoh, Yoshitake Masuda
Summary: The authors synthesized diamond- and square-type Cu-metal-organic frameworks (MOFs) and converted them to CuO nanostructures, with CuO-D showing higher gas sensitivity compared to CuO-S due to the presence of coordinatively unsaturated metal sites on the exposed (111) facet.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Electrochemistry
Katsuhiro Nomura, Hiroyuki Shimada, Yuki Yamaguchi, Woosuck Shin, Yuji Okuyama, Yasunobu Mizutani
Summary: The phase transitions, thermal expansions, chemical expansions, and CO2 resistances of two different compositions of perovskite materials were investigated. The results show that the composition of the materials plays an important role in determining their properties.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Chemistry, Analytical
Toshio Itoh, Noriya Izu, Akihiro Tsuruta, Takafumi Akamatsu, Woosuck Shin, Kenji Kamihoriuchi, Masao Takizawa, Isao Yoshida
Summary: The study developed a cerium oxide thick film semiconductor sensor for measuring oxygen concentration in simulated exhaled gas, finding that sensor response to the gas depends on the frequency of the AC signal and the morphology of the platinum electrode at a given frequency.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Multidisciplinary
Kyusung Kim, Phuwadej Pornaroontham, Pil Gyu Choi, Toshio Itoh, Yoshitake Masuda
Summary: The advancement of nanomaterial technologies has allowed for the development of gas sensors capable of detecting gases at extremely low concentrations. However, fluctuation in response values based on operating conditions poses a critical challenge. To address this issue, a self-adaptive system based on a predictive model and operating conditions has been proposed.
Article
Nanoscience & Nanotechnology
Pil Gyu Choi, Kyusung Kim, Toshio Itoh, Yoshitake Masuda
Summary: A thin film of SnO2 nanosheets was synthesized for MEMS devices as a sensing material, showing superior sensitivity and specificity for biomarker gases. The introduction of SnO2 nanosheets led to better separation of gases, indicating the potential for clear distinction of gas species and convenient health monitoring.
ACS APPLIED NANO MATERIALS
(2021)
Article
Environmental Sciences
Toshio Itoh, Yoshitake Masuda, Ichiro Matsubara, Junichirou Arai, Woosuck Shin
Summary: This study analyzed the temporal variation of VOCs composition in four essential oils. The results revealed that the concentration level of VOCs in the oils varied with diffusion time and equilibrium concentration with the liquid phase. It was confirmed that the total concentration of VOCs diffused by the ultrasonic diffuser in room air was very low.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2022)
Article
Materials Science, Ceramics
Katsuhiro Nomura, Hiroyuki Shimada, Yuki Yamaguchi, Hirofumi Sumi, Yasunobu Mizutani, Yuji Okuyama, Woosuck Shin
Summary: Using various machine learning models, the space groups of Ba(Ce0.8-xZrx)Y0.2O3 (0 <= x <= 0.8) perovskite-type protonic conductors were predicted in a wide temperature range. The models were trained using data of chemical formulas, space groups obtained from high-temperature X-ray and neutron diffraction, and different datasets. The best accuracy and F1 score were achieved by the Random Forest model with a coordination number of 9 for oxygen of the A-site cation.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Hiroyuki Shimada, Hirofumi Sumi, Yuki Yamaguchi, Katsuhiro Nomura, Yasunobu Mizutani, Yoshinobu Fujishiro, Woosuck Shin
Summary: This study presents high-performance nanocomposite cathode and anode layers that greatly improve the power density of solid oxide fuel cells (SOFCs).
JOURNAL OF POWER SOURCES
(2023)
Article
Materials Science, Ceramics
Woosuck Shin, Yuki Yamaguchi, Mirano Horie, Hiroyuki Shimada, Katsuhiro Nomura, Hirofumi Sumi
Summary: This study investigates the application of porous metals in solid oxide fuel cells using machine learning methods. The process conditions for oxide layers and metal particles are examined, and it is found that random forest, a multi-output method, predicts the target variables with higher accuracy compared to neural network. Additionally, the relationship between the microstructure of metal supported cells and their power generation performance is discussed.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Analytical
Toshio Itoh, Yutaro Koyama, Yuichi Sakumura, Takafumi Akamatsu, Akihiro Tsuruta, Yoshitake Masuda, Woosuck Shin
Summary: We investigated the discriminant method for identifying volatile organic compounds (VOCs) in exhaled breath under both contaminated and purified air conditions using multiple semiconductive gas sensors and linear discriminant analysis (LDA) technique. Our developed discriminant method was used to analyze the resistance changes in sensor signals in the LDA space. The target gases were discriminated based on the angle of the locus of the test data in the 2-D LDA space. Our results demonstrated the feasibility of this method in discriminating target gases under contaminated air conditions.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
