检索结果-南通市图书馆

Capillary grip-induced stick-slip motion

在线全文

学校读者我要写书评

暂无评论

Nano Research 2022年第8期15卷 7384-7391页

作者： Sangmin An Manhee Lee Bongsu Kim wonho jhe Department of Physics&Astronomy Seoul National UniversitySeoul 08826Republic of Korea Department of Physics Institute of Photonics and Information TechnologyJeonbuk National UniversityJeonju 54896Republic of Korea Department of Physics Chungbuk National UniversityCheongjuChungbuk 28644Republic of Korea Samsung Advanced Institute of Technology(SAIT) Samsung ElectronicsSuwon 16678Republic of Korea

We present capillary grip-induced stick-slip motion,a nanoscale tribological effect,where the role of a nanoscale confined water meniscus formed between a buckled sharp tip and a glass or mica surface is addressed by shear dynamic force *** obtained the effective elasticity,viscosity,conservative(elastic)and non-conservative(viscous)forces,energy dissipation,and lateral force using small oscillation,amplitude-modulation,and shear-mode quartz tuning fork-atomic force microscopy(QTFAFM).We distinguished the conservative and non-conservative forces by investigating the dependence of normal load and relative humidity,slip length,and stick-slip *** found that the confined nanoscale water enhances the lateral forces via capillary grip-induced stick-slip on a rough surface,resulting in an increase of static lateral force(3-fold for both substrates)and kinetic lateral force(6-fold for glass,3-fold for mica).This work provides quantitative and systematic understanding of nanoscale tribology properties in humid ambient conditions and is thus useful for control of friction as well as characterization of tribology in nanomaterials and nanodevices.

关键词： dynamic force measurement nanoscale water meniscus relative humidity lateral force stick-slip motion

Sorting Gold and Sand(Silica) Using Atomic Force Microscope-Based Dielectrophoresis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2022年第2期14卷 1-11页

作者： Chungman Kim Sunghoon Hong Dongha Shin Sangmin An Xingcai Zhang wonho jhe Department of Physics and Astronomy Seoul National UniversitySeoul 08826Republic of Korea John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138United States Department of Chemistry and Chemical Engineering Inha UniversityIncheon 22212Republic of Korea Department of Physics Institute of Photonics and Information TechnologyJeonbuk National UniversityJeonju 54896Korea School of Engineering Massachusetts Institute of TechnologyCambridgeMA 02139United States

Additive manufacturing-also known as 3D printing-has attracted much attention in recent years as a powerful method for the simple and versatile fabrication of complicated three-dimensional ***,the current technology still exhibits a limitation in realizing the selective deposition and sorting of various materials contained in the same reservoir,which can contribute significantly to additive printing or manufacturing by enabling simultaneous sorting and deposition of different substances through a single ***,we propose a dielectrophoresis(DEP)-based material-selective deposition and sorting technique using a pipette-based quartz tuning fork(QTF)-atomic force microscope(AFM) platform DEPQA and demonstrate multi-material sorting through a single nozzle in ambient *** used Au and silica nanoparticles for sorting and obtained 95% accuracy for spatial separation,which confirmed the surfaceenhanced Raman spectroscopy(SERS).To validate the scheme,we also performed a simulation for the system and found qualitative agreement with the experimental *** method that combines DEP,pipette-based AFM,and SERS may widely expand the unique capabilities of 3D printing and nano-micro patterning for multi-material patterning,materials sorting,and diverse advanced applications.

关键词： Dielectrophoresis-empowered Pipette/AFM platform On-demand materials sorting Additive 3D printing Multimaterial nano-patterning Nanopipette-based atomic force microscope

Fabrication and Characterization of Au Nanoparticle-aggregated Nanowires by Using Nanomeniscus-induced Colloidal Stacking Method

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2015年第1期7卷 27-34页

作者： Sangmin An wonho jhe Department of Physics and Astronomy Institute of Applied Physics Seoul National University Center for Nanoscale Science and Technology National Institute of Standards and Technology

We fabricate and characterize Au nanoparticle-aggregated nanowires by using the nano meniscus-induced colloidal stacking method. The Au nanoparticle solution ejects with guidance of nanopipette/quartz tuning fork-based atomic force microscope in ambient conditions, and the stacking particles form Au nanoparticle-aggregated nanowire while the nozzle retracts from the surface. Their mechanical properties with relatively low elastic modulus are in situ investigated by using the same apparatus.

关键词： Au nanoparticle-aggregated nanowire Nanomeniscus-induced colloidal stacking method Atomic force microscope Liquid–solid coexistence phase

Position-resolved Surface Characterization and Nanofabrication Using an Optical Microscope Combined with a Nanopipette/Quartz Tuning Fork Atomic Force Microscope

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2014年第1期6卷 70-79页

作者： Sangmin An Baekman Sung Haneol Noh Corey Stambaugh Soyoung Kwon Kunyoung Lee Bongsu Kim Qhwan Kim wonho jhe Center for Nano-Liquid Department of Physics and AstronomySeoul National University National Institute of Standards and Technology

In this work, we introduce position-resolved surface characterization and nanofabrication using an optical microscope(OM) combined with a nanopipette-based quartz tuning fork atomic force microscope(nanopipette/QTF-AFM) system. This system is used to accurately determine substrate position and nanoscale phenomena under ambient conditions. Solutions consisting of 5 nm Au nanoparticles, nanowires, and polydimethylsiloxane(PDMS) are deposited onto the substrate through the nano/microaperture of a pulled pipette. Nano/microscale patterning is performed using a nanopipette/QTF-AFM, while position is resolved by monitoring the substrate with a custom OM. With this tool, one can perform surface characterization(force spectroscopy/microscopy) using the quartz tuning fork(QTF) sensor. Nanofabrication is achieved by accurately positioning target materials on the surface, and on-demand delivery and patterning of various solutions for molecular architecture.

关键词： Surface characterization Nanopipette QTF-AFM Optical microscope