Modeling Perfusion Dynamics in the Skin During Iontophoresis of Vasoactive Drugs Using Single-Pulse and Multiple-Pulse Protocols

ABSTRACTWe have experimentally Investigated the effects that are associated with Multiple-pulse irradiation in the excimer laser processing of thin Si films on SiO2. Double-pulse irradiation experiments revealed results, which are consistent with that which is known from single-pulse crystallization experiments, and these experiments confirm the applicability of the transformation scenarios, which were derived from single pulse-induced crystallization experiments [1,2]. The results from the Multiple-pulse irradiation experiments clearly show that gradual and substantial grain enlargement can occur — and only occurs — when the irradiation energy density is close to but less than the level that is required to melt the film completely. Based on these findings, we argue that the grain enlargement effect is a near-complete melting phenomenon that is associated with polycrystalline Si films, and we present a grain boundary melting model to account for this phenomenon. A brief discussion on the apparent similarities and physical differences between the observed phenomenon and the solid state grain growth processes is provided herein.

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Laser Damage Thresholds of Several Metal-Containing Acrylic Polymers at Four Different Wavelengths.

MRS Proceedings ◽

10.1557/proc-236-501 ◽

1991 ◽

Vol 236 ◽

Cited By ~ 1

Author(s):

Pearl W. Yip

Keyword(s):

Electron Spectroscopy ◽

Light Transmission ◽

Single Pulse ◽

Laser Damage ◽

Laser Materials ◽

Acrylic Polymers ◽

Multiple Pulse ◽

Chemical Damage ◽

Before And After ◽

Physical And Chemical

AbstractSingle- and multiple-pulse laser damage thresholds of six different metal-containing acrylic polymers were determined at 10.6, 1.06, 0.53 and 0.355 μm. Light transmission of these samples before and after irradiation was measured. A variety of observed laser-materials interactions are discussed in this paper. Physical and chemical damage properties of these metal-containing acrylic polymers were examined and compared with poly (methyl methacrylate) and polycarbonate using scanning electron microscopy (SEM), infrared spectroscopy (IR), and electron spectroscopy for chemical analysis (ESCA). In general, it was found that the multiple-pulse damage thresholds were lower than the single-pulse, and damage thresholds decreased as wavelength of the testing laser beam became shorter.

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Microhardness of the Surface Layer of Tungsten and Molybdenum After Recrystallization With Laser Radiation

Journal of Engineering Materials and Technology ◽

10.1115/1.2903368 ◽

1991 ◽

Vol 113 (1) ◽

pp. 130-134 ◽

Cited By ~ 1

Author(s):

F. Kostrubiec ◽

M. Walczak

Keyword(s):

Surface Layer ◽

Laser Radiation ◽

Laser Beam ◽

Single Pulse ◽

Glass Laser ◽

Multiple Pulse ◽

And Tungsten

We present results of microhardness measurements in melted local regions in molybdenum and tungsten. Microhardness has been measured by the Vickers method. Melted regions have been produced by pulsed Nd-glass laser. The emphasis is on correlation between conditions of recrystallization (energy of laser beam and method of irradiation-single pulse or multiple pulse) and the microhardness value.

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Target Localization Methods Based on Iterative Super-Resolution for Bistatic MIMO Radar

Electronics ◽

10.3390/electronics9020341 ◽

2020 ◽

Vol 9 (2) ◽

pp. 341

Author(s):

Jianhe Du ◽

Meng Han ◽

Libiao Jin ◽

Yan Hua ◽

Shufeng Li

Keyword(s):

Multiple Input Multiple Output ◽

Super Resolution ◽

Single Pulse ◽

Doa Estimation ◽

Mimo Radar ◽

Target Localization ◽

Localization Accuracy ◽

Bistatic Mimo Radar ◽

Multiple Pulse ◽

Direction Of Departure

The direction-of-departure (DOD) and the direction-of-arrival (DOA) are important localization parameters in bistatic MIMO radar. In this paper, we are interested in DOD/DOA estimation of both single-pulse and multiple-pulse multiple-input multiple-output (MIMO) radars. An iterative super-resolution target localization method is firstly proposed for single-pulse bistatic MIMO radar. During the iterative process, the estimated DOD and DOA can be moved from initial angles to their true values with high probability, and thus can achieve super-resolution estimation. It works well even if the number of targets is unknown. We then extend the proposed method to multiple-pulse configuration to estimate target numbers and localize targets. Compared with existing methods, both of our proposed algorithms have a higher localization accuracy and a more stable performance. Moreover, the proposed algorithms work well even with low sampling numbers and unknown target numbers. Simulation results demonstrate the effectiveness of the proposed methods.

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Single-Pulse and multiple-pulse femtosecond spectroscopy of ferroelectric materials

Ferroelectrics ◽

10.1080/00150199508221826 ◽

1995 ◽

Vol 164 (1) ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

Lisa Dhar ◽

Bernd Burfeindt ◽

Keith A. Nelson ◽

C. M. Foster

Keyword(s):

Single Pulse ◽

Femtosecond Spectroscopy ◽

Ferroelectric Materials ◽

Multiple Pulse

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Effect of Multiple Pulses on the Deformation Behavior of Ultrathin Metal Foils in 3D Micro-Scale Laser Dynamic Forming

ASME 2010 International Manufacturing Science and Engineering Conference, Volume 2 ◽

10.1115/msec2010-34299 ◽

2010 ◽

Author(s):

Ji Li ◽

Gary J. Cheng

Keyword(s):

Deformation Behavior ◽

Laser Energy ◽

3D Structure ◽

Single Pulse ◽

Laser Pulses ◽

High Energy ◽

Shock Pressure ◽

Thickness Variation ◽

Multiple Pulse ◽

Multiple Pulses

Laser dynamic forming (LDF) is a novel high energy rate microfabrication technique, which makes use of the shock pressure induced by laser to generate dynamic high strain rate 3D forming of thin films. In LDF process, a high shock pressure accelerates the workpiece to a high velocity and deforms it into complex 3D shapes. The forming velocity of the workpiece imparted by a single laser pulse with high energy may exceed the critical forming velocity of the material, and thus causing it to fracture. This problem is more severe when 3D structure of large aspect ratio needs to be formed. To overcome this problem, multi-pulse laser dynamic forming is investigated in this study. The total laser energy is evenly distributed in different laser pulses to keep the forming velocity below the critical forming velocity of the material. The effects of the multiple-pulse LDF on the deformation behavior of ultra thin foils are investigated. The deformation depth and thickness variation distribution of the formed 3D features are characterized to reveal these effects. In addition, the effects of vacuum conditions on multiple-pulse LDF process are carried out. It is found that the bounce off of the foil can be effectively reduced by multiple-pulse LDF and the final shape could be controlled much more accurately. By extending single pulse LDF to multi-pulse LDF, the forming capability of LDF is further enhanced, and thus enlarges the applicable range of this technique.

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