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Tagging is demonstrated in argon and nitrogen gases using a femtosecond laser with pulse energies of approximately 70 μJ through a nonresonant ionization process at 267 nm. The signal fluorescence lifetime in pure argon and nitrogen-argon mixtures are measured and found to be long enough to make mean velocity and turbulence measurements in a subsonic flow. In pure argon, the dominating processes involve atomic transitions between 700 and 900 nm. In argon-nitrogen mixtures, nitrogen quenches atomic argon species and the dominant radiating processes are transitions in the nitrogen second positive system. In pure nitrogen, emission on the microsecond time scale comes from the nitrogen first positive system. Lower energy density is needed for tagging and narrower tagged lines are produced using 267 nm as compared to femtosecond laser tagging in argon and nitrogen using 400 nm or 800 nm. Velocimetry using the 267 nm line is demonstrated in a turbulent argon pipe flow and the Taylor microscale of the flow is determined.
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The background and results for two simplified read schemes for krypton tagging velocimetry (KTV) are presented. The first scheme utilizes the excitation/re-excitation approach found in the literature ...
Argon laser peripheral iridoplasty (ALPI) could be effective in widening residual angle closure following laser peripheral iridotomy (LPI).
Femtosecond laser mass spectrometry (FLMS) has become an important tool for investigation of chemical and biological materials in many areas from medical to industrial.
Diamond's nitrogen vacancy (NV) center is an optically active defect with long spin coherence times, showing great potential for both efficient nanoscale magnetometry and quantum information processin...
To determine whether scatter argon laser photocoagulation can prevent the development of neovascularization. To determine whether peripheral scatter argon laser photocoagulation can preve...
Since femtosecond laser was approved for cataract surgery by FDA in 2010, femtosecond laser assisted cataract surgery (FLACS) has demonstrated high precision of capsulotomy, reduced phacoe...
The objective of this clinical trial is to evaluate the safety and effectiveness of the Carl Zeiss Meditec VisuMax™ Femtosecond Laser lenticule removal procedure for the reduction or eli...
In this clinical trial study,the investigators intend to compare two methods of trichiasis treatment.One by argon laser and the other by radiofrequency then compare the result of these pro...
Introduction: Pterygium is a wing shape degenerative and hyperplastic growth of the bulbar conjunctiva extending onto the cornea, most commonly on the nasal side. Management of pterygium c...
Progressive mental disturbances and unconsciousness due to breathing mixtures of oxygen and inert gases (argon, helium, xenon, krypton, and atmospheric nitrogen) at high pressure.
Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.
A method of tissue ablation and bleeding control that uses argon plasma (ionized argon gas) to deliver a current of thermocoagulating energy to the area of tissue to be coagulated.
A technique utilizing a laser coupled to a catheter which is used in the dilatation of occluded blood vessels. This includes laser thermal angioplasty where the laser energy heats up a metal tip, and direct laser angioplasty where the laser energy directly ablates the occlusion. One form of the latter approach uses an EXCIMER LASER which creates microscopically precise cuts without thermal injury. When laser angioplasty is performed in combination with balloon angioplasty it is called laser-assisted balloon angioplasty (ANGIOPLASTY, BALLOON, LASER-ASSISTED).
Techniques using laser energy in combination with a balloon catheter to perform angioplasty. These procedures can take several forms including: 1, laser fiber delivering the energy while the inflated balloon centers the fiber and occludes the blood flow; 2, balloon angioplasty immediately following laser angioplasty; or 3, laser energy transmitted through angioplasty balloons that contain an internal fiber.