A5009767255- Fluid Dynamics and Turbulent Flows
- Microfluidic and Bio-sensing Technologies
- Microfluidic and Capillary Electrophoresis Applications
- Aerodynamics and Acoustics in Jet Flows
- Plasma and Flow Control in Aerodynamics
- Advanced MEMS and NEMS Technologies
- Advanced biosensing and bioanalysis techniques
- Innovative Microfluidic and Catalytic Techniques Innovation
- Heat Transfer Mechanisms
- Fluid Dynamics and Vibration Analysis
- Electrowetting and Microfluidic Technologies
- Electrohydrodynamics and Fluid Dynamics
- Computational Fluid Dynamics and Aerodynamics
- Advanced Sensor Technologies Research
- Analytical Chemistry and Sensors
- Mechanical and Optical Resonators
- 3D Printing in Biomedical Research
- Heat Transfer and Optimization
- Biosensors and Analytical Detection
- Nanofabrication and Lithography Techniques
- Advanced Biosensing Techniques and Applications
- Gas Dynamics and Kinetic Theory
- Surface Modification and Superhydrophobicity
- Cellular Mechanics and Interactions
- Biomimetic flight and propulsion mechanisms
University of California, Los Angeles
2013-2024
Fu Jen Catholic University
2014-2024
Cathay General Hospital
2006-2024
National Tsing Hua University
2024
Samueli Institute
2008-2024
UCLA Jonsson Comprehensive Cancer Center
2005-2018
Shanghai Jiao Tong University
2017
University of California System
1998-2016
La Jolla Bioengineering Institute
2016
China Medical University Hospital
2016
▪ Abstract The micromachining technology that emerged in the late 1980s can provide micron-sized sensors and actuators. These micro transducers are able to be integrated with signal conditioning processing circuitry form micro-electro-mechanical-systems (MEMS) perform real-time distributed control. This capability opens up a new territory for flow control research. On other hand, surface effects dominate fluid flowing through these miniature mechanical devices because of large...
In the present study, it is shown that spreading rate of a mixing layer can be greatly manipulated at very low forcing level if perturbed near subharmonic most-amplified frequency. The technique able to make several vortices merge simultaneously and hence increases dramatically. A new mechanism, ‘collective interaction’, was found which bypass sequential stages vortex merging large number (ten or more) coalesce. deeper physical insight into evolution coherent structures revealed through...
Two switchable, palindromically constituted bistable [3]rotaxanes have been designed and synthesized with a pair of mechanically mobile rings encircling single dumbbell. These designs are reminiscent "molecular muscle" for the purposes amplifying harnessing molecular mechanical motions. The location two cyclobis(paraquat-p-phenylene) (CBPQT4+) can be controlled to on either tetrathiafulvalene (TTF) or naphthalene (NP) stations, chemically (1H NMR spectroscopy) electrochemically (cyclic...
A passive technique of increasing entrainment was found by using a small-aspect-ratio elliptic jet. The ratio an jet several times greater than that circular or plane self-induction the asymmetric coherent structure caused azimuthal distortions which were responsible for engulfing large amounts surrounding fluid into In jet, interesting feature in initial stability process is thickness shear layer varies around nozzle. data indicated instability frequency scaled with thinnest momentum...
Fast advancements of microfabrication processes in past two decades have reached to a fairly matured stage that we can manufacture wide range microfluidic devices. At present, the main challenge is control nanoscale properties on surface lab-on-a-chip satisfy need for biomedical applications. For example, poly(dimethylsiloxane) (PDMS) commonly used material circuitry, yet hydrophobic nature PDMS suffers serious nonspecific protein adsorption. Thus current major efforts are focused molecular...
In a high-speed subsonic jet impinging on flat plate, the surface pressure fluctuations have broad spectrum due to turbulent nature of high-Reynolds-number jet. However, these dramatically change their pattern into almost periodic waves, if plate is placed close nozzle (x0/d < 7·5). present study extensive measurements near-field provide solid support for hypothesis that feedback mechanism responsible sudden observed in at onset resonance. The loop consists two elements: downstream-convected...
For about a decade it has been noticed from the measurements of many jets that value preferred mode and spreading rate vary within range 100%. In present paper is suggested extremely low-level spatially coherent disturbances in individual facilities change initial conditions laminar shear layer. The various are able to cause different downstream developments jet result discrepancies reported literature.
Enabled by a technology to fabricate well-defined nanogrates over large area (2×2cm2), we report the effect of such surface, in both hydrophilic and hydrophobic conditions, on liquid slip corresponding friction reduction microchannels. The grates are designed be dense (∼230nm pitch) but deep (∼500nm) order sustain amount air troughs when hydrophobic, even under pressurized flow conditions (e.g., more than 1bar). A noticeable (i.e., length 100–200nm, 20%–30% pressure drop ∼3μm high channel)...
<h3>Background</h3> Since morbidity and mortality rates due to oral cavity oropharyngeal squamous cell carcinoma (OSCC) have improved little in the past 30 years, early detection or prevention of this disease is likely be most effective. Using laser-capture microdissection, we identified expression 2 cellular genes that are uniquely associated with OSCC: interleukin (IL) 6 IL-8. These cytokines may contribute pathogenesis disease, been linked increased tumor growth metastasis....
Liquid/gas flows are experimentally investigated in 200 and 525 μm square microchannels made of glass silicon. Liquid gas mixed a cross-shaped section way to produce steady homogeneous monodisperse bubbles. Two-phase flow map transition lines between regimes examined. Bubble velocity slip ratio liquid measured. Flow patterns their characteristics discussed. Local global dry out the channel walls by moving bubbles capillaries as function for partially wetting channels. pressure drop is...
A macroscopic evaporating water droplet with suspended particles on a solid surface will form ring-like structure at the pinned contact line due to induced capillary flow. As size shrinks, competition between time scales of liquid evaporation and particle movement may influence resulting ring formation. When evaporates much faster than movement, coffee formation cease. Here, we experimentally show that there exists lower limit size, Dc, for successful structure. concentration is above...
We present a compact mobile phone platform for rapid, quantitative biomolecular detection. This system consists of an embedded circuit signal processing and data analysis, disposable microfluidic chips fluidic handling biosensing. Capillary flow is employed sample loading, processing, pumping to enhance operational portability simplicity. Graphical step-by-step instructions displayed on the assists operator through detection process. After completion each measurement, results are screen...
This Letter reports experimental results on the coalescence of two liquid drops driven by surface tension. Using a high speed imaging system, we studied early-time evolution bridge that is formed upon initial contact in air. Experimental confirmed scaling law was proposed Eggers et al. based simple and yet elegant physical argument. We found radius rb follows rb∝t1/2 inertial regime. Further experiments demonstrate such robust when using fluids different viscosities tensions. The prefactor...
Emerging micromachining technology enables us to fabricate mechanical parts on the order of micron size. It provides with micro-sensors and micro-actuators which facilitate exploration all areas science. Furthermore, these miniature transducers can be integrated microelectronics. With an system, it then becomes possible complete loop sensing, information processing, actuation. This type system perform real-time control time varying events are common in fluid dynamics. In this review paper,...
Electrokinetics is the study of motion bulk fluids or selected particles embedded in when they are subjected to electric fields. With recent developments microfabrication, electrokinetics provides effective manipulation techniques micro and nano domains, which matches length scale various biological objects. The ability manipulate objects down molecular levels opens new avenues exploit science technology. Understanding fundamental characteristics limitations forces becomes a crucial issue...
Abstract Purpose: Multiplexing assay of biomarkers at the point-of-care is an elusive goal for molecular diagnostics. Experimental Design: Here, we report electrochemical (EC) sensor oral cancer detection based on simultaneous two salivary biomarkers: interleukin (IL)-8 mRNA and IL-8 protein. Results: Under multiplexing mode, limit reaches to 3.9 fM 7.4 pg/mL protein in saliva. Multiplex these 2 directly from 28 matched control saliva samples shows significant difference between groups. From...
An experimental study was conducted to investigate the’ generation process of random small-scale turbulence in an originally laminar mixing layer. The evolutions the two types deterministic structures, spanwise and streamwise vortices, were first clarified order determine their roles transition process. A scaling rule for distance from trailing edge splitter plate vortex merging position found various velocity ratios. After this lengthscale determined, it became clear that wavelength...
An array of microcantilever beams, coated with a self-assembled monolayer bistable, redox-controllable [3]rotaxane molecules, undergoes controllable and reversible bending when it is exposed to chemical oxidants reductants. Conversely, beams that are redox-active but mechanically inert control compound do not display the same bending. A series experiments rational assessments preclude influence heat, photothermal effects, pH variation as potential mechanisms beam Along simple calculation...
A vortex-induced unsteady separation was investigated experimentally in the laminar boundary layer produced by an axisymmetric jet impinging normally onto a flat plate. By forcing air jet, primary ring vortices were periodically generated shear layer. Phase-locked flow visualization showed that wall-jet separated and evolved into secondary vortex counter rotating with respect to vortex. The is induced moves downstream radial mean-flow direction. Phase-averaged hot-wire measurements using...
A general strategy was developed to transform aptamers into highly sensitive and selective optical sensors. This accomplished with an unmodified aptamer as the molecular recognition element a competitor oligo, which completely or partially complementary aptamer, signal transduction element. Displacement of oligos in presence targets resulted detectable readout. Successful application this has been demonstrated not only different types (small molecules proteins), but also (DNA RNA). high...