Implementing compact, efficient, and reliable passive pulsed lasers at visible wavelengths is attractive. This paper systematically investigated the thickness-dependent optical absorption characteristics of two-dimensional materials, including graphene, transition-metal dichalcogenides, dye films 532 nm wavelength band, revealed effects thickness on different parameters. The results suggested t...

a new sensitive, simple and rapid method for determination of methotrexate (mtx) was developed based on quenching effects of mtx on the fluorescence intensity of tb3+-1,10-phenanthroline complex. the fluorescence intensity was measured with excitation wavelength of 300 nm and emission wavelength of 545 nm and the quenched fluorescence intensity is proportional to the concentration of mtx in tris...

Variation in visual spectral tuning has evolved in concert with signal colour in some taxa, but there is limited evidence of this pattern in birds. To further investigate this possibility, we compared spectral sensitivity among bowerbird species that occupy different visual habitats and are highly diverged in plumage and decoration colour displays, which are important in mate choice and possibl...

Cichlid fish inhabit a diverse range of environments that vary in the spectral content of light available for vision. These differences should result in adaptive selective pressure on the genes involved in visual sensitivity, the opsin genes. This study examines the evidence for differential adaptive molecular evolution in East African cichlid opsin genes due to gross differences in environment...

The brilliantly coloured cone oil droplets of the avian retina function as long-pass cut-off filters that tune the spectral sensitivity of the photoreceptors and are hypothesized to enhance colour discrimination and improve colour constancy. Although it has long been known that these droplets are pigmented with carotenoids, their precise composition has remained uncertain owing to the technical...

a simple and sensitive extraction-spectrophotometric method for rapid and accurate determination of benzocaine in pure and dosage forms was developed. benzocaine was effectively extracted as a 1:1 ion pair complex with dicyclohexyl-18-crown-6 and calmagite in acidic media into chloroform, followed by spectrophotometric determination at 486 nm. molar absorptivity of the ternary complex at this w...

A simple and sensitive extraction-spectrophotometric method for rapid and accurate determination of benzocaine in pure and dosage forms was developed. Benzocaine was effectively extracted as a 1:1 ion pair complex with dicyclohexyl-18-crown-6 and calmagite in acidic media into chloroform, followed by spectrophotometric determination at 486 nm. Molar absorptivity of the ternary complex at this w...

Microspectrophotometry was used to measure the visual pigments in the rods and cones of 22 species of marine fish larvae netted from the surface waters off Friday Harbor Laboratories, Washington, USA. 13 species had rods, 12 of which contained visual pigments with a wavelength of maximum absorbance near 500 nm, while one, the sand lance (Ammodytes hexapterus), had its absorbance maximum at 482 ...

In optical testing, when the wave-front error of a test optic is much larger than the wavelength of visible light, it may be difficult to analyze the closely spaced interference fringes in the interferogram. The use of a less-sensitive testing technique or a long-wavelength interferometer would be preferred for this purpose. In addition, when the optic is to be tested in transmission, the wavel...