An LC postcolumn derivatization method for determination of polythiols has been developed. This method involves separation using reversed-phase LC, postcolumn derivatization with N-(1-pyrenyl)maleimide, and excimer fluorescence detection. Analytes with a polythiol structure were converted into corresponding polypyrene-labeled derivatives, and the derivatives exhibited intramolecular excimer flu...

Resent technical progress of laser technologies for microlithography is discussed here. The performance of highly durable 2kHz KrF excimer laser, and next generation light source of 2kHz ArF excimer laser, which are realized by the new technologies, are discribed. We also discuss about its impact on microlithography. Further more F2 laser development program in Japan and its latest result which...

PURPOSE The expression of heat shock protein 47 (HSP47) was observed histologically to investigate the spatial and chronological effects of excimer laser photoablation. HSP47 expression after radial keratotomy (RK) was also investigated and compared with the effects after excimer laser photoablation. METHOD Twenty-eight male rabbits were used. The rabbits were divided with two groups and trea...

Pyrene is a spatially sensitive probe that displays an ensemble of monomeric fluorescence emission peaks (375-405 nm) and an additional band (called excimer) at ~460 nm when two fluorophores are spatially proximal. We examined if there is a correlation between distance between two pyrenes on an α-helical structure and excimer/monomer (e/m) ratio. Using structure-guided design, pyrene maleimide ...

Human enamel surface was irradiated with ArF excimer laser and examined under light microscopy and scanning electron microscopy (SEM). Enamel surface was irradiated at three different areas with different energy fluences. It is demonstrated that the ArF excimer laser causes ablation of the calcified hard enamel tissue. Ablation curves were measured. There was no significant difference found in ...

The first commercial excimer laser was introduced 40 years ago by Lambda Physik (now Coherent; Santa Clara, CA). Interestingly, its developers— Bernd Steyer and Dirk Basting—were both chemists whose main goal was to develop a light source for photochemistry and dye laser pumping. As soon as excimer lasers entered the market, Lambda Physik began to investigate other possible uses for a powerful ...

A tunable ArF* (193-nm) excimer source is described that produces over 125 mJ/pulse (peak) at 10 pulses/sec. This device has a spectral width of less than 2 cm(-1) and a demonstrated tunability of nearly 320 cm(-1) from 192.8 to 193.9 nm. Tunability, bandwidth, and mode control are achieved by injecting the fourth anti-Stokes line (in H(2)) of a frequency-doubled dye laser into an ArF* excimer-...

Si ion implantation was widely used to synthesize specimens of SiO2 containing supersaturated Si and subsequent high temperature annealing induces the formation of embedded luminescent Si nanocrystals. In this work, the potentialities of excimer UV-light (172 nm, 7.2 eV) irradiation and rapid thermal annealing (RTA) to enhance the photoluminescence and to achieve low temperature formation of Si...

Just when we thought photorefractive keratectomy (PRK) had achieved a level of safety and predictability in correcting refractive errors in our patients, new wounding healing information regarding apoptosis (programmed cell death) surfaces to show us that the way we remove the corneal epithelium matters a great deal in how the corneal stroma responds to our treatment.1 Excimer laser manufacture...

PURPOSE To evaluate long-term results of sequential customized therapeutic keratectomy (SCTK) in highly aberrated corneas with apical scars consequent to hyperopic excimer laser refractive surgery. METHODS Fifteen eyes of 12 patients treated with SCTK for a corneal apical scar after hyperopic excimer laser refractive surgery were retrospectively evaluated. SCTK is a sequence of custom therape...