The photostability of tretinoin tocoferil was investigated under irradiation with three kinds of lamps, i.e., a cool white fluorescent lamp, a UV-A fluorescent lamp and a D65 fluorescent lamp. A combination of the cool white fluorescent lamp and the UV-A fluorescent lamp, and the D65 lamp having relative spectral power distribution similar to that of direct daylight, correspond to options 2 and...

TiO2-doped SnO2 nanopowder is synthesized via a sol-gel method and characterized by atomic force microscopy and X-ray diffraction. Using this nanopowder, we have fabricated a novel semiconductor gas sensor that is sensitive to UV light illumination. We find that gas-sensing properties of TiO2-doped SnO2 sensor can be enhanced significantly under the exposure of UV light. The sensor exhibits a h...

Laboratory measurements were performed to characterize the geometrical effects in the calibration of the NASA's cloud absorption radiometer (CAR). The measurements involved three integrating sphere sources (ISSs) operated at different light levels and experimental setups to determine radiance variability. The radiance gradients across the three ISS apertures were 0.2%-2.6% for different visible...

Light is one of the most important environmental factors, acting on plants not only as the sole source of energy, but also as the source of external information, affecting their growth and development. Plants are empowered with an array of photoreceptors controlling diverse responses to light parameters, such as spectrum, intensity, direction, duration etc. These photoreceptors include the red ...

We report the formation of directionally-ordered nanoscale surface domains on the +z face of undoped congruent lithium niobate single crystals by using UV illumination through a phase mask of sub-micron periodicity with an energy fluence between ~90 mJ/cm 2 and 150 mJ/cm 2 at λ=266 nm. We clearly show here that the UV-induced surface ferroelectric domains only nucleate at and propagate along ma...

A simple method to make a switchable liquid crystal (LC) Fresnel lens with high diffraction efficiency and a low driving voltage was proposed based on the photo-induced surface modification of the vertical alignment layer. UV illumination alters the pretilt angle of alignment layers, a Fresnel zone-distribution hybrid alignment in the homeotropic LC cell can be straightforwardly achieved throug...

Graphene is a 2D material that has been widely researched for its potential as gas-sensing material, but environment-sensitive electronic properties have limited use in practical applications. In this work, graphene chemi-resistive sensor first integrated with 3D-printed fused silica chamber an internal volume of 50 µl. The adsorption film are then regenerated using ultraviolet illumination. We...

We have studied the UV sensitivity degradation of CsI and KBr thin films under UV illumination and the stability of their visible light rejection for CsI and KBr opaque photocathodes evaporated on microchannel plates. For both materials the greatest degradation of the relative quantum detection efficiency (QDE) was observed near the photocathode sensitivity cut off, while there was almost no ch...