INTRODUCTION Laser lithotripsy of bile duct stones has become a widely accepted endoscopic treatment modality for giant, impacted, or very hard stones. The procedure is usually carried out under direct endoscopic control in view of the potential risk of bile duct injuries in "blind" laser application. AIMS To investigate the use of a rhodamine 6G laser lithotriptor with an integrated optical ...

Absolute fluorescence quantum yields are reported for the rhodamine 6G cation and the fluorescein dianion dyes in nine solvents. This information is combined with previously reported fluorescence lifetimes to deduce radiative and nonradiative decay rates. Along the alcohol series from methanol to octanol, rhodamine 6G displays an increasing radiative rate, in parallel with the square of the ref...

Stimulated emission depletion (STED) population and polarisation dynamics are used to determine 40 α the degree of hexadecapole alignment created in ensembles of rhodamine 6G molecules in solution following two-photon excitation. Hexadecapole molecular alignment is an unavoidable consequence of two-photon excitation but is not observed in spontaneous emission. For a single element diagonal tran...

Rhodamine 6G-chromone-derived compounds RD1 - RD4 have been synthesized by condensation of rhodamine 6G hydrazide and substituted chromone aldehydes in ethanol using microwave-assisted reaction. The structures these derivatives were confirmed proton nuclear magnetic resonance (1H-NMR), carbon (13C-NMR), high-resolution mass spectra data (HRMS). Colorimetric photophysical studies show the select...

Aqueous solutions of ultra-pure gold nanoparticles have been prepared by methods of femtosecond laser ablation from a solid target and fragmentation from already formed colloids. Despite the absence of protecting ligands, the solutions could be (1) fairly stable and poly size-dispersed; or (2) very stable and monodispersed, for the two fabrication modalities, respectively. Fluorescence quenchin...

This investigation explores, for the first time, the random laser behavior of ground powder obtained from organic-inorganic hybrid materials based on Rhodamine 6G incorporated into a di-ureasil matrix. The experimental results, both in the spectral and temporal domains, obtained by pumping with picosecond laser pulses, show the existence of efficient random laser emission in this system. Finall...

Fluorescence Resonance Energy Transfer between two dyes Fluorescein and Rhodamine 6G were investigated in solution in the presence and absence of Zinc oxide nanoparticle. Zinc oxide nanostructure is used as the fluorescence enhancing agent for the present study since donor (Fluorescein) fluorescence increase significantly in presence of nanoparticle. Accordingly, the energy transfer efficiency ...

This study investigates the effect of photobleaching on laser-induced fluorescence (LIF) measurements. Photobleaching causes the fluorescence to be velocity-dependent, which is undesirable if quantitative measurements are being made. To quantify this effect, simultaneous and coincident measurements of fluorescence and velocity were made within the measuring volume of a three-beam laser-Doppler ...

We present a polymer based microfluidic dye laser suitable for integration into micro total analysis systems, fabricated by nanoimprint lithography (NIL) [1] in the thermoplastic polymer COC (cyclo olefin copolymer) [2]. The device (se figure 1 and 2) consists of microfluidic channels, with sizes ranging from several mm down to 16 μm, and optical waveguides, all fabricated in one single NIL ste...