Article
Biochemical Research Methods
Bookun Kim, Sung Sik Lee, Tae Hyeon Yoo, Ju Min Kim
Summary: This study found that under pressure-driven microflows, particles in human saliva and blood plasma are influenced by their viscoelastic properties, forming a focused stream. The degree of particle focusing varies among samples, indicating that the viscoelasticity of biofluids may be affected by their compositions.
Article
Chemistry, Multidisciplinary
Guantong Wang, Masaki Kudo, Kazuho Daicho, Sivasankaran Harish, Bin Xu, Cheng Shao, Yaerim Lee, Yuxuan Liao, Naoto Matsushima, Takashi Kodama, Fredrik Lundell, L. Daniel Soederberg, Tsuguyuki Saito, Junichiro Shiomi
Summary: This study demonstrates that nanocellulose materials can exhibit high thermal conductivity when their nanofibrils are highly aligned and bonded. The crystallinity of the filaments significantly influences their thermal conductivity.
Article
Chemistry, Analytical
Haidong Feng, Alexander R. Jafek, Bonan Wang, Hayden Brady, Jules J. Magda, Bruce K. Gale
Summary: This paper studies particle focusing in viscoelastic flow and predicts the focusing position by analyzing the force balance. The research finds that particle separation resolution can be improved in viscoelastic flows.
Article
Biochemical Research Methods
Dan Yuan, Sharda Yadav, Hang T. Ta, Hedieh Fallahi, Hongjie An, Navid Kashaninejad, Chin Hong Ooi, Nam-Trung Nguyen, Jun Zhang
Summary: This study investigated sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel, demonstrating its application on various types of particles and cells. The zigzag structure of the channel allows for reduced device footprint and channel length without sacrificing focusing performance.
Article
Mechanics
M. Lopez, M. G. Cabezas, J. M. Montanero, M. A. Herrada
Summary: In this study, the stability of hydrodynamic focusing to produce microemulsions is investigated experimentally and numerically. It is found that the distance between the feeding capillary and the focusing orifice affects the liquid ejection stability. Confined selective withdrawal enhances the stability of the microdripping mode. Surfactants stabilize the meniscus and promote the transition from microdripping to jetting. The global stability analysis accurately predicts the critical flow rate ratio and the droplet emission frequency.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Wenjun Yuan, Mengqi Zhang, Boo Cheong Khoo, Nhan Phan-Thien
Summary: This paper investigates the inline rise of a pair of three-dimensional air bubbles in a viscoelastic liquid using direct numerical simulations. The study reveals the interaction patterns, coalescence, and separation tendencies of bubble pairs, as well as the impact of fluid elasticity on their behavior. The findings highlight the importance of long-range repulsion and short-range attraction in bubble pair interactions in viscoelastic fluids.
Article
Computer Science, Interdisciplinary Applications
Maan Al-Zareer
Summary: This paper introduces a microfluidic separation device based on hydrodynamic focusing, equipped with dual neodymium magnets for positive magnetophoretic microparticles and cell separation. By minimizing damage to the particles through different inlet flow rates, efficient separation of particles is achieved.
MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING
(2022)
Article
Chemistry, Analytical
Hiroshi Yamashita, Takeshi Akinaga, Masako Sugihara-Seki
Summary: The study focused on the effect of Reynolds number on inertial focusing in rectangular duct flows. Numerical simulations were conducted to analyze the lift force on spherical particles in the duct, determining the lift-force distribution map over a wide range of Reynolds numbers. The study identified different particle-focusing patterns based on the duct cross-section shape and Reynolds number, including subcritical pitchfork and supercritical pitchfork bifurcations.
Article
Chemistry, Analytical
Mohammad Moein Naderi, Ludovica Barilla, Jian Zhou, Ian Papautsky, Zhangli Peng
Summary: The study on elasto-inertial focusing highlighted the interaction between elastic force and shear-gradient lift force leading to different particle focusing patterns. Both experimental and simulation studies were conducted to investigate the effects of flowrate, particle size, and shear-thinning extent on focusing patterns, emphasizing the importance of accurately estimating shear-thinning extent in modeling.
Article
Mechanics
Li Gaojin, Lauga Eric, Arezoo M. Ardekani
Summary: The article reviews the locomotion of microorganisms and spermatozoa in complex viscoelastic fluids, discussing their responses to different propulsion mechanisms and physical factors. It summarizes the theoretical approaches for modeling microswimming in viscoelastic fluids and recent progress in studying single cell mobility in unbounded viscoelastic fluids. Lastly, it examines the impact of viscoelasticity on microswimmers' dynamics and collective cellular behavior.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2021)
Article
Nanoscience & Nanotechnology
Yen-Heng Lin, Ching-Hui Chang
Summary: A simple and reusable three-dimensional microfluidic hydrodynamic focusing device is proposed for fluorescent particle counting and fluorescence intensity detection, assembled using commercially available glass capillaries. The device can provide a symmetric three-dimensional hydrodynamic focus flow by matching the inner diameter of a square capillary with the outer diameter of a circular capillary. It is capable of controlling the diameter of the focused flow by adjusting the flow rates, allowing accurate counting of fluorescent particles and detection of fluorescence intensity.
MICROFLUIDICS AND NANOFLUIDICS
(2021)
Article
Chemistry, Analytical
Yong Qin, Liang-Liang Fan, Liang Zhao
Summary: A new method using a reverse external force was proposed to efficiently focus aerosol particles in a microchannel. A numerical model of particle movement in the microchannel was established, and simulations were conducted to study the gas-particle two-phase flow under the effect of the reverse external force. The results showed that a suitable reverse external force could significantly enhance the Saffman lift force on the aerosol particle, resulting in efficient particle focusing in the microchannel.
Article
Multidisciplinary Sciences
Louis William Rogowski, Jamel Ali, Xiao Zhang, James N. Wilking, Henry C. Fu, Min Jun Kim
Summary: This study demonstrates the spontaneous symmetry-breaking propulsion of rotating spherical microparticles within non-Newtonian fluids, providing new possibilities for microscale propulsion technology. The existence of two equal and opposite propulsion states along the sphere's rotation axis challenges previous symmetry analysis and offers insights into novel propulsion mechanisms for microswimmers.
NATURE COMMUNICATIONS
(2021)
Article
Mechanics
Yunxing Su, Alfonso Castillo, On Shun Pak, Lailai Zhu, Roberto Zenit
Summary: In this study, it is found that due to the asymmetric shear-induced elastic stresses, a dense sphere rotating near a wall can levitate at a fixed distance away from the wall by generating a net elastic vertical force.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Biochemistry & Molecular Biology
Dianguo Wu, Yiwen Shi, Kun Lv, Bing Wei, Youyi Zhu, Hongyao Yin, Yujun Feng
Summary: This study presents a simple method for fabricating CO2-switchable viscoelastic fluids using commercially available materials, allowing control of solution viscosity and elasticity by bubbling CO2 into and removing CO2 from the solution. The research widens the potential applications of CO2 in stimuli-responsive applications.
Article
Chemistry, Physical
Suyeon Lee, Hyung Min Kim, Dong Gi Seong, Doojin Lee
Article
Mechanics
Hyung Min Kim, Suyeon Lee, Young Seok Song, Doojin Lee
COMPOSITE STRUCTURES
(2019)
Article
Materials Science, Textiles
Dong Gi Seong, Jung Soo Kim, Moon Kwang Um, Doojin Lee
FIBERS AND POLYMERS
(2019)
Article
Materials Science, Textiles
Hansu Kim, Juhyuk Park, Kyung Suh Minn, Seong Yeol Pak, Doojin Lee, Jae Ryoun Youn, Young Seok Song
FIBERS AND POLYMERS
(2019)
Article
Chemistry, Multidisciplinary
Nikhil Bhalla, Aditya Jain, Yoonjoo Lee, Amy Q. Shen, Doojin Lee
Article
Materials Science, Multidisciplinary
Se Yeon Song, Min Soo Park, Doojin Lee, Jung Woo Lee, Ji Sun Yun
MATERIALS & DESIGN
(2019)
Article
Materials Science, Composites
Jaehyun Cho, Hyeseong Lee, Ki-Ho Nam, Hyeonuk Yeo, Cheol-Min Yang, Dong Gi Seong, Doojin Lee, Seong Yun Kim
COMPOSITES SCIENCE AND TECHNOLOGY
(2020)
Article
Chemistry, Analytical
Doojin Lee, Amy Q. Shen
Summary: Droplet microfluidics provides a versatile tool for measuring interfacial tensions between immiscible fluids, with the ability to generate emulsion droplets and stretch them under controlled flow conditions in microfluidic devices. The use of quasi-static 2D and 3D models allows for accurate estimation of interfacial tension in confined and unconfined droplet cases during extensional flows, demonstrating the effectiveness of these models compared to conventional techniques.
Article
Materials Science, Ceramics
Jinsu Ha, Yeeun Song, Nayoung Song, Ji Sun Yun, Doojin Lee
Summary: In this study, an interpenetrating network of silane-functionalized nanocomposites was designed to enhance particle dispersity and interfacial bonding strength. Through rheological characterizations and modeling, the study confirmed the accuracy of predicting particle dispersity index and elastic modulus, illustrating the significant impact of interphase regions on interfacial bonding strength and mechanical properties in nanocomposites. Additionally, the Mori-Tanaka micromechanics model successfully verified the existence of a good interpenetrating network between nanoparticles and matrix.
CERAMICS INTERNATIONAL
(2022)
Article
Multidisciplinary Sciences
Amir Farokh Payam, Bogyoung Kim, Doojin Lee, Nikhil Bhalla
Summary: This study proposes a new analytical model for characterizing liquid slip using vibrating solid surfaces. The model is validated by experiments and shows that liquid slip, which is independent of surface wetting condition, occurs especially at high flow rates. This slip has significant effects on the resonant frequency changes and energy dissipation of the vibrating solid. The findings are important for considering the "missing slip" phenomenon in vibrating solid-liquid systems such as QCM-based biosensors, where flow conditions are traditionally overlooked in interpreting frequency changes.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sang Hyun Ji, Yeeun Song, Doojin Lee, Ji Sun Yun
Summary: To develop air filters with high-efficiency fine particulate matter (PM) capture properties, the study investigated the electrospinnability of natural cellulose nanofibers. The cellulose nanofibers were prepared by mixing trifluoroacetic acid and 1,2-dichloroethane with various types of cellulose. The study found that the cellulose precursor solution with hardwood pulp exhibited the optimal electrospinnability and achieved high-efficiency PM capture characteristics.
MATERIALS & DESIGN
(2023)
Article
Polymer Science
Bogyoung Kim, Yeeun Song, Byungwook Youn, Doojin Lee
Summary: We investigated the relationship between surface chemistry and rheological properties in silicon anode slurries. Various binders were used to control particle aggregation and improve flowability and homogeneity. Zeta potential analysis showed that binder conformation on silicon particles can be influenced by neutralization and pH conditions. The results demonstrated the importance of considering surface chemistry, neutralization, and pH conditions when assessing the rheological properties of the slurry and coating quality for lithium-ion batteries.
Article
Materials Science, Textiles
Yeeun Song, Young Jun Joo, Yangyul Ju, Byungwook Youn, Dong Geun Shin, Kwang Youn Cho, Doojin Lee
Summary: The study focuses on investigating the effect of ion mobility on changes in the crystal lattice of silicon carbides derived from polycarbosilane precursors. The rheological properties and fiber spinnability of aluminum-containing polycarbosilane precursors were studied to understand the polymer networking, further polymerization, and structural rearrangement behaviors during the spinning process. By elucidating the temperature ranges for continuous and uniform jetting of the precursors, enhanced network formation through further polymerization and structural rearrangement was achieved, resulting in increased formation of polycrystalline nanograins in uniform-sized silicon carbide fibers.
FIBERS AND POLYMERS
(2023)
Review
Mechanics
Eunseo Jeon, Haneum Kim, Garim Kim, Doojin Lee
Summary: This review provides a comprehensive examination of rheological techniques for studying bacterial biofilms, highlighting the importance and applications of rheological measurements in biofilm research.
KOREA-AUSTRALIA RHEOLOGY JOURNAL
(2023)
Article
Materials Science, Multidisciplinary
Bogyoung Kim, Byungwook Youn, Yeeun Song, Doojin Lee
Summary: This study prepared POSS functionalized graphene oxide (GO) to improve the dispersity of GO nanofillers in a polydimethylsiloxane matrix. The improved interfacial affinity and enhanced elasticity were confirmed, resulting in better filler dispersibility and less filler aggregation in the matrix.
FUNCTIONAL COMPOSITES AND STRUCTURES
(2022)
