Article
Materials Science, Multidisciplinary
Deliang Zhang, Zibo Li, Lasse Hyldgaard Klausen, Qiang Li, Mingdong Dong
Summary: This article summarizes the friction behaviors and underlying physical mechanisms of 2D materials, with an increased understanding of their friction properties thanks to the development of atomic and friction force microscopy. The effects of atomic structures and external factors on friction, as well as strategies for friction modulation, are discussed. The challenges in practical applications of 2D materials as atomically thin lubricants and the prospects for future progression are also provided.
MATERIALS TODAY PHYSICS
(2022)
Article
Engineering, Mechanical
Tianyan Gao, Kaisen Zhang, Xiaojun Liu, Kun Liu, Jiaxin Ye
Summary: Friction and unloading experiments of an ox-Si3N4 ball against a PDMS film were conducted using an in-situ optical microtribometer. The results indicate that a transient friction coefficient significantly higher than in dry condition always occurred in wet conditions, with influences from discretely distributed nanoscaled water bridges, increased pull-off force, stick-slip amplitude, and contact deformation.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Nanoscience & Nanotechnology
F. C. Liu, P. Dong
Summary: This study successfully controlled the development of intermetallic compounds at the Al-Fe interface through FSW experiments, reducing the thickness layer to a nanoscale amorphous phase and providing new insights and methods for joining aluminum alloy and steel without detrimental IMCs.
SCRIPTA MATERIALIA
(2021)
Article
Biochemical Research Methods
Nithya Kasireddy, Jeremy C. Orie, Damir B. Khismatullin
Summary: The researchers introduce a novel noncontact rheological technique called acoustic tweezing spectroscopy (ATS) for sensitive small-volume rheological analysis.
Article
Chemistry, Physical
Janet A. W. Elliott
Summary: This article aims to explore the validity of three major thermodynamic combined equilibrium equations at the smallest radius of curvature, providing conceptual, molecular modeling, and experimental evidence to support that these equations could be valid at smaller scales.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Yanxiao Li, Shuohan Huang, Congjie Wei, Dong Zhou, Bo Li, Vadym N. Mochalin, Chenglin Wu
Summary: This study experimentally demonstrates that MXenes have low coefficients of friction at the nanoscale. It also shows that the friction of MXenes is less affected by the number of monolayers compared to other materials, and hydrogen bonding between MXenes results in higher friction forces.
Article
Chemistry, Physical
Airi N. Kato, Yujie Jiang, Wei Chen, Ryohei Seto, Tao Li
Summary: The study shows that colloidal particles can be trapped at a liquid interface, reducing the interfacial area. Colloids with rough surfaces undergo various self-assemblies and structural transitions. Experimental and numerical simulations reveal that sufficiently rough systems exhibit a gel state between gas-like and close-packed jamming states. Roughness-induced friction and tangential contact forces contribute to the formation of gel state and collapse of compressed monolayer.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Evangelos Liamas, Simon D. Connell, Morfo Zembyla, Rammile Ettelaie, Anwesha Sarkar
Summary: This study showed that the modulus of a surface can significantly affect the frictional properties of protein-coated surfaces, with higher deformability leading to lower contact pressure and decreased friction.
Article
Physics, Fluids & Plasmas
Manhee Lee, Hyouju Choi, Bongsu Kim, Jongwoo Kim
Summary: This study shows analytically that the molecular dynamics of capillary bridges in the interfacial fluid result in both elastic and dissipative forces on the shearing plane. Surprisingly, the nanometer-sized, liquid-solid contact line of the bridges exerts an enormous shear force on the solid surface, which is 10(5) times higher than the usual viscous interaction and comparable to solid-solid direct-contact friction. These findings are consistent with previous experimental data and offer insights into the apparent viscosity of nanoconfined fluids.
Article
Chemistry, Analytical
David Klenerman, Yuri Korchev, Pavel Novak, Andrew Shevchuk
Summary: The reduction in ion current near a cell surface when a fine pipette approaches allows imaging of cell surface topography with nanoscale resolution without damaging the delicate surface. By combining various methods such as single-channel recording, force application, and fluorescence imaging, there is great potential to image and map live cell surfaces at the nanoscale with high resolution and speed.
ANNUAL REVIEW OF ANALYTICAL CHEMISTRY, VOL 14, 2021
(2021)
Article
Geosciences, Multidisciplinary
D. L. P. de Lacerda, R. Prioli, Y. M. Parizek-Silva, G. F. Vasquez
Summary: This study proposes the use of atomic force microscopy and energy dispersive spectroscopy to identify shale components and measure the in situ tribomechanical properties of different phases. Frictional characteristics of the major shale constituents were obtained and the identification of different phases was performed. The results show that friction is higher for organic matter and shear strength is higher for quartz and lower for organic matter.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Levente Juhasz, Roberto D. Ortuso, Kaori Sugihara
Summary: The study utilized quantitative friction force microscopy to measure the response of polydiacetylene to lateral forces, revealing the necessity of applying shear forces to characterize it at the nanoscale. The experiment confirmed the erroneous nature of the hypothesis regarding the higher force sensitivity at the edges and discovered a correlation between mechanochromism and thermochromism.
Article
Chemistry, Physical
Pengchang Wei, Yong Xiong, Yuan-Yuan Zheng, Ali Zaoui, Zhen-Yu Yin, Weiwei Niu
Summary: By using Steered Molecular Dynamics (SMD) simulations, the nanoscale friction behavior of quartz-quartz and quartz-kaolinite interfaces is investigated. The study discusses the effects of normal load, sliding velocity, temperature, and hydration on the friction behavior, and reveals the friction mechanism of these interfaces. The simulation results show the presence of a stick-slip effect and its dependence on sliding velocity, hydration, and normal load. The friction load increases with the rising normal load, and the relationship between shear stress and normal load is approximately linear. The friction coefficient and cohesion of the quartz-quartz interface can increase with increasing sliding velocity or decreasing temperature. Additionally, the presence of clay significantly weakens the frictional strength of quartz in the quartz-kaolinite interface. The effect of the interlayer water film on friction behavior shows both lubricating and bonding roles, which are discussed and analyzed in the study.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Article
Chemistry, Physical
Zhe Chen, Seong H. Kim
Summary: This study used atomic force microscopy to investigate the effect of water and n-pentanol adsorption on the nanoscale friction of graphite. The results showed that as the humidity increases, friction on the basal plane increases, while friction at the step edge first increases and then decreases. Additionally, adsorption of n-pentanol decreases friction on both the basal plane and step edge.
APPLIED SURFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Alexandre Fromain, Jose Efrain Perez, Aurore van de Walle, Yoann Lalatonne, Claire Wilhelm
Summary: This study demonstrates that photothermia at the nanoscale can trigger the degradation of magnetic nanoparticles, leading to the release of Fe(II) and enabling photothermo-ferroptotic therapy. The temperature acts as an accelerator for nanoparticle degradation and can be remotely triggered by laser-mediated photothermal conversion. The efficacy of this treatment method has been confirmed in in vitro experiments.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Jungheum Yun, Haemi Lee, ChaeWon Mun, Junghoon Jahng, William A. Morrison, Derek B. Nowak, Jung-Hwan Song, Dong-Kwon Lim, Tae-Sung Bae, Hyung Min Kim, Nam Hoon Kim, Sang Hwan Nam, Jongwoo Kim, Min-Kyo Seo, Dong-Ho Kim, Sung-Gyu Park, Yung Doug Suh
Article
Chemistry, Multidisciplinary
Youngkyu Hwang, Seonggwang Yoo, Namsoo Lim, Sang Myeong Kang, Hyeryun Yoo, Jongwoo Kim, Yujun Hyun, Gun Young Jung, Heung Cho Ko
Article
Nanoscience & Nanotechnology
Hye Sun Park, Jongwoo Kim, Mi Young Cho, Youn-Joo Cho, Yung Doug Suh, Sang Hwan Nam, Kwan Soo Hong
ACS APPLIED MATERIALS & INTERFACES
(2020)
Article
Biophysics
Jong-Hwan Lee, Minsuk Choi, Yujin Jung, Sung Kyun Lee, Chang-Seop Lee, Jung Kim, Jongwoo Kim, Nam Hoon Kim, Bum-Tae Kim, Hong Gi Kim
Summary: This study presents a novel rapid detection method for the SARS-CoV-2 S1 antigen using a matched pair of ACE2 and antibody. The detection method showed high specificity and sensitivity without cross-reactivity, making it a valuable tool in detecting the S1 antigen from COVID-19 patients.
BIOSENSORS & BIOELECTRONICS
(2021)
Article
Environmental Sciences
Jun-Hyung Lim, Sang Hwan Nam, Jongwoo Kim, Nam Hoon Kim, Gun-Soo Park, Jin-Soo Maeng, Se-Jin Yook
Summary: A three-stage high-volume bioaerosol sampler was developed for size-selective sampling of bioaerosols at a high flow rate of 1000 L/min, enabling detection of viruses in crowded public places. The sampler collects bioaerosols in different size ranges, allowing for analysis via polymerase chain reaction to confirm the presence of viruses.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Biophysics
Jun-Hyung Lim, Sang Hwan Nam, Jongwoo Kim, Nam Hoon Kim, Gun-Soo Park, Jin-Soo Maeng, Se-Jin Yook
Summary: In this study, a three-stage bio-aerosol sampler was designed and fabricated to effectively sample bio-aerosols released during human breathing and coughing. The sampler's performance was evaluated through simulations and experiments, and it showed similar sampling performance to a commercial product, enabling direct collection of samples in a collection fluid for PCR analysis.
JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Chemistry, Multidisciplinary
Jongwoo Kim, Hye Sun Park, Yun Ahn, Youn-Joo Cho, Hyeon Ho Shin, Kwan Soo Hong, Sang Hwan Nam
Summary: This article presents a new single-particle spectroscopy technique to study the emission characteristics and energy transfer mechanisms of upconverting nanoparticles (UCNPs), aiming to achieve brighter UCNPs and expand their applications.
Article
Multidisciplinary Sciences
Changhwan Lee, Emma Z. Z. Xu, Kevin W. C. Kwock, Ayelet Teitelboim, Yawei Liu, Hye Sun Park, Benedikt Ursprung, Mark E. E. Ziffer, Yuzuka Karube, Natalie Fardian-Melamed, Cassio C. S. Pedroso, Jongwoo Kim, Stefanie D. D. Pritzl, Sang Hwan Nam, Theobald Lohmueller, Jonathan S. S. Owen, Peter Ercius, Yung Doug Suh, Bruce E. E. Cohen, Emory M. M. Chan, P. James Schuck
Summary: Photoswitchable probes, such as organic fluorophores and proteins, have limitations including photodegradation and operation only in UV or visible spectral regions. This study introduces avalanching nanoparticles (ANPs) that can be switched bidirectionally with near-infrared (NIR) light, offering improved stability. The mechanism of the photoswitching process is elucidated through modeling and measurement of the photon avalanche properties of single ANPs. The unlimited, reversible photoswitching of ANPs enables multilevel optical patterning and sub-A localization superresolution optical nanoscopy.
Article
Chemistry, Multidisciplinary
Yeongchang Goh, Jongwoo Kim, Hye Sun Park, Taeyoung Jung, Kwan Soo Hong, Sang Hwan Nam, Yung Doug Suh, Kang Taek Lee
Summary: Cell-cell communication is crucial for cellular differentiation, organ function, and immune responses. This study demonstrates the use of dual-colour imaging with upconverting nanoparticles to visualize the intercellular transport of cargo molecules, and shows that extracellular vesicles can be transmitted along with fluorescently labelled proteins.
Article
Physics, Fluids & Plasmas
Manhee Lee, Hyouju Choi, Bongsu Kim, Jongwoo Kim
Summary: This study shows analytically that the molecular dynamics of capillary bridges in the interfacial fluid result in both elastic and dissipative forces on the shearing plane. Surprisingly, the nanometer-sized, liquid-solid contact line of the bridges exerts an enormous shear force on the solid surface, which is 10(5) times higher than the usual viscous interaction and comparable to solid-solid direct-contact friction. These findings are consistent with previous experimental data and offer insights into the apparent viscosity of nanoconfined fluids.
Article
Chemistry, Multidisciplinary
Dohyun Kim, Jongwoo Kim, Jonggeun Hwang, Dongha Shin, Sangmin An, Wonho Jhe
Summary: This study directly measured the critical size of a single capillary-condensed nanomeniscus using atomic force microscopy, revealing the relationship between surface tension of alcohols and curvature, and finding that larger curvature results in increased surface tension, affecting nucleation behavior. The research on curvature effects contributes to better understanding and accurate analysis of nucleation processes in fields such as materials science and atmospheric science.
Article
Chemistry, Multidisciplinary
Jongwoo Kim, Jeong Seop Lee, Ji-woong Kim, Peter De Wolf, Seunghyun Moon, Dong Hwan Kim, Joo-Hyun Song, Jungwoo Kim, Taewan Kim, Sang Hwan Nam, Yung Doug Suh, Kyoung-Ho Kim, Hyunwoo Kim, ChaeHo Shin
Summary: NTIL technology enables precise control of the size and shape of plasmonic nanostructures by adjusting the indentation force and shape of AFM tips, thereby regulating their localized surface plasmon resonance and polarization-dependent plasmon modes.
Article
Chemistry, Multidisciplinary
Hyunwoo Kim, Seunghyun Moon, Jongwoo Kim, Sang Hwan Nam, Dong Hwan Kim, Jeong Seop Lee, Kyoung-Ho Kim, Evan S. H. Kang, Kwang Jun Ahn, Taewan Kim, ChaeHo Shin, Yung Doug Suh
Summary: The study investigated photoluminescence enhancement from few-layer MoS2 transferred on Au nanostructure arrays with controlled localized surface plasmon resonance (LSPR) spectral positions. Two distinctive regimes in LSPR mode-dependent PL enhancement were revealed, with a maximum enhancement of around 40-fold at zero detuning and a modest enhancement of around 10-fold with red-shift detuned LSPR, attributed to LSPR-induced optical field enhancement and the Purcell effect, respectively.
Article
Chemistry, Multidisciplinary
Jongwoo Kim, Sang Hwan Nam, Dong-Kwon Lim, Yung Doug Suh
Article
Materials Science, Multidisciplinary
G. Murali, Sandeep Kaur, Jongwoo Kim, Sang Hwan Nam, Joong Hee Lee, Yung Doug Suh, Insik In, Seung Hee Lee
JOURNAL OF MATERIALS CHEMISTRY C
(2019)
