Can only macroscopic objects be moved by light beams? On the 12th, the reporter learned from the Institute of Fundamentals and Frontiers of the University of Electronic Science and Technology that Prof. Wang Zhiming’s team and collaborators from Henan University of Engineering, Houston University, Harvard University and other universities have discovered a new mechanism of photo-fluidics and succeeded. Pulsed lasers are used to drive continuous high-speed water jets in pure water. Relevant papers have been published online at the frontier of Science and on the front page of the home page. Efficiently using pulsed lasers to directly drive liquid flow has always been a problem that has plagued the scientific community at home and abroad. Wang Zhiming's team discovered the new mechanism of photo-hydrodynamics by first adding gold nanoparticles to the solution, using the photoacoustic effect to achieve the first drive of the liquid to the liquid; then replacing the liquid containing gold nanoparticles with pure water, again After being irradiated with a pulsed laser, it was found that it can continue to drive the water flow in pure water at a high speed. In order to uncover this magical phenomenon, the team found that in the first experiment, the laser focused on the inner wall of the glass dish produced a microfluidic chamber with a large number of gold nanoparticles. This “crater†microcavity is the solution after the solution replacement. The key that can still be driven by the laser. “This 'crater' connects the photoacoustic effect and the acoustic wave driving effect.†Wang Zhiming said that after the microcavity is irradiated with laser, under the combined action of the gold nanoparticles and the cavity, directional high-frequency ultrasonic waves can be generated through the sound waves. Driving effect, driving the dispersion to generate high-speed flow can generate ultrasonic waves and drive liquid flow. "This new optical fluid mechanism organically combines the two basic physical processes of the photoacoustic effect and the acoustic wave driving fluid effect, and finally realizes the driving of the liquid by the laser." He said that under this principle, once micro After the cavity is formed and the gold nanoparticle dispersion is replaced with pure water or other solution, the laser can still drive other liquids to flow. (Ke Huaihong reporter Shengli) Retarder, a kind of admixture for concrete, is used to reduce the hydration speed and heat of hydration of cement or gypsum and prolong the setting time. In order to meet the needs of our customers, we can provide you with a variety of different types of retarders for your choice. Concrete Admixture,Hydroxyethyl Acrylate,Admixture Calcium Lignosulphonate,Calcium Lignosulfonate Liquid Shenyang East Chemical Science-Tech Co., Ltd. , https://www.eastchemy.com
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New mechanism of laser-driven liquid flow