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Full-Text Articles in Mechanical Engineering
A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe
A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe
Joan Carletta
In this work we demonstrate an on-chip multiplexed multichannel resistive pulse sensor (Coulter counter) for high throughput counting of microscale particles. The design, fabrication and testing of this device are presented. The high throughput counting is a result of using multiple parallel microfluidic channels to analyze the sample. Detection is achieved by using frequency division multiplexing; each microchannel is modulated with its own known and unique frequency, a combined measurement is made across a single pair of electrodes, and the measured signal is demodulated to determine the signal across each individual channel. Testing results using 30 µm polystyrene particles demonstrate …
A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe
A Microfluidic Multichannel Resistive Pulse Sensor Using Frequency Division Multiplexing For High Throughput Counting Of Micro Particles, Ashish Jagtiani, Joan Carletta, Jiang Zhe
Dr. Jiang Zhe
In this work we demonstrate an on-chip multiplexed multichannel resistive pulse sensor (Coulter counter) for high throughput counting of microscale particles. The design, fabrication and testing of this device are presented. The high throughput counting is a result of using multiple parallel microfluidic channels to analyze the sample. Detection is achieved by using frequency division multiplexing; each microchannel is modulated with its own known and unique frequency, a combined measurement is made across a single pair of electrodes, and the measured signal is demodulated to determine the signal across each individual channel. Testing results using 30 µm polystyrene particles demonstrate …
Suppression Of Atomic Friction Under Cryogenic Conditions: The Role Of Athermal Instability In Afm Measurements, Yalin Dong, Hongyu Gao, Ashlie Martini
Suppression Of Atomic Friction Under Cryogenic Conditions: The Role Of Athermal Instability In Afm Measurements, Yalin Dong, Hongyu Gao, Ashlie Martini
Dr. Yalin Dong
A theoretical investigation of the behavior of atomic friction at low temperatures is performed using a master equation method with a two-mass, two-spring Prandtl-Tomlinson model of an atomic force microscope experiment. A novel approach is taken in which two distinct instability mechanisms are introduced into the model: thermal activation is described by transition state theory with a prefactor associated with the frequency of the tip apex, and athermal instability is introduced by an Arrhenius-like equation with a prefactor associated with the characteristic frequency of the cantilever. Thermal instability causes the often reported decrease of friction with temperature followed by a …
Effects Of Particle's Off-Axis Position, Shape, Orientation And Entry Position On Resistance Changes Of Micro Coulter Counting Devices, Zhenpeng Qin, Jiang Zhe, Guo-Xiang Wang
Effects Of Particle's Off-Axis Position, Shape, Orientation And Entry Position On Resistance Changes Of Micro Coulter Counting Devices, Zhenpeng Qin, Jiang Zhe, Guo-Xiang Wang
Dr. Jiang Zhe
With the recent advance in micro/nano-fabrication technology, micro Coulter counters have been widely used in detecting and characterizing micro- and nanoscale objects. In this paper, the electrical resistance change during translocation of a non-conducting particle through a channel is studied numerically. The numerical results are validated by proven analytical results available in the literature. The effects of particle's off-axis position, shape and orientation, and entry position are studied for particles with a large dynamic range. From the numerical results, a new fitted correlation is proposed that can accurately predict the resistance change caused by off-axis spherical particles regardless of their …
Effects Of Particle's Off-Axis Position, Shape, Orientation And Entry Position On Resistance Changes Of Micro Coulter Counting Devices, Zhenpeng Qin, Jiang Zhe, Guo-Xiang Wang
Effects Of Particle's Off-Axis Position, Shape, Orientation And Entry Position On Resistance Changes Of Micro Coulter Counting Devices, Zhenpeng Qin, Jiang Zhe, Guo-Xiang Wang
Dr. Guo-Xiang Wang
With the recent advance in micro/nano-fabrication technology, micro Coulter counters have been widely used in detecting and characterizing micro- and nanoscale objects. In this paper, the electrical resistance change during translocation of a non-conducting particle through a channel is studied numerically. The numerical results are validated by proven analytical results available in the literature. The effects of particle's off-axis position, shape and orientation, and entry position are studied for particles with a large dynamic range. From the numerical results, a new fitted correlation is proposed that can accurately predict the resistance change caused by off-axis spherical particles regardless of their …