A simplified system for measuring time-resolved photoluminescence (PL) induced by UV laser pulses (lambda = 337 nm) is designed by a combination of a commercial PL reader and a digital oscilloscope. Using this system, PL emissions after pulsed UV excitation from a chip of sapphire (Al2O3) are successfully measured with intervals of 10 ns. It is thus expected that this system will be convenientl...

Background: In the light of various applications of UV laser in biological system, we have investigated the effect of picosecond UV laser radiation on silkworm Bombyx mori. Materials and Methods: The eggs of NB4D2 of different stages were exposed to pico second pulse laser at 355 nm from Nd:YAG laser for different durations. Results: Due to irradiation alterations in crescent larval body...

Light has been used to noninvasively alter the excitability of both neural and cardiac tissue 1-10. Recently, pulsed laser light has been shown to be capable of eliciting action potentials in peripheral nerves and in cultured cardiomyocytes 7-10. Here, we demonstrate for the first time optical pacing (OP) of an intact heart in vivo. Pulsed 1.875 μm infrared laser light was employed to lock the ...

background: in the light of various applications of uv laser in biological system, we have investigated the effect of picosecond uv laser radiation on silkworm bombyx mori. materials and methods: the eggs of nb4d2 of different stages were exposed to pico second pulse laser at 355 nm from nd:yag laser for different durations. results: due to irradiation alterations in crescent larval body markin...

This work studied the effect of additions of carbon dioxide to argon shielding gas on the weld shape and microstructure of ST14 steel in pulsed Nd: YAG laser welding. By additions of carbon dioxide up to 15%,the weld area and depth/width ratio decreases while rising of carbon dioxide up to 25% causes increasing of weld area and depth/width ratio. It is observed that the weld metal microstructur...

Nanosecond optical pulses with high power and spectral brightness in the deep ultraviolet (UV) region have been produced by sum frequency mixing of nearly transform-limited-bandwidth IR light originating from a home-built injection-seeded ring cavity KTiOPO(4) optical parametric oscillator (OPO) and the fourth harmonic beam of an injection-seeded Nd:YAG laser used simultaneously to pump the OPO...

A very compact explosive vapor sensor is demonstrated based on a distributed feedback polymer laser pumped by a commercial InGaN light-emitting diode. The laser shows a two-stage turn on of the laser emission, for pulsed drive currents above 15.7 A. The 'double-threshold' phenomenon is attributed to the slow rise of the ∼30 ns duration LED pump pulses. The laser emits a 533 nm pulsed output bea...

graphene oxide was prepared using modified hummers method. stable ethylene-glycol nanofluids containing graphene oxide nanosheets were provided. nd: yag pulsed laser was applied to prepare reduced nanofluids. experimental results revealed that thermal conductivity of the nanofluids is increased with increasing the concentration of graphene oxide (go) in ethylene glycol. the enhancement ratio of...

Ag nanoparticles and Ag-TiO2 nanostructures were grown on (001) SiO2 quartz substrates by pulsed laser deposition using a KrF* excimer laser source (λ= 248 nm, τFWHM~10 ns, ν= 10 Hz) for the irradiation of Ag and TiO2 targets. The obtained structures were characterized by atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-visible absorption spectroscopy. Photoc...

Introduction Melasma and postinflammatory hyperpigmentation (PIH) are conditions commonly encountered by dermatologists, they often distressing to patients. While PIH can improve with time once the inflammatory process is controlled, melasma a condition that requires prolonged treatment maintenance. There numerous options, ranging from UV protection topical therapies (such as hydroquinone), mor...