We have fabricated ZnS, ZnSe and mixed Zn(S,Se) thin film layers for application as solar cell absorbers in ultraviolet (UV)-selective cells. the using a two-step process involving evaporation of Zn layer followed by an anneal H2S and/or H2Se containing atmosphere. A study annealing conditions was performed to minimize hole formation layer. Sulfur Selenium also developed order reach 3 eV band g...

SCIAMACHY onboard the environmental research satellite ENVISAT is a UV/visible/near-infrared grating spectrometer providing 3 near infrared channels covering wavelengths from 1-1.75μm, 1.94-2.04μm and 2.262.38μm with moderate spectral resolution (0.22-1.5nm) (Bovensmann et al. 1999). Among the absorbers in these regions are the greenhouse gases CO2, CH4, N2O and H2O as well as CO. A modified DO...

Azobenzenes have been noted for their ability to undergo isomerization between the straight trans isomer and the bent cis isomer with visible light and UV irradiation, respectively. Their photochemically induced isomerization make them highly useful in optical switching devices. Time-dependent density functional theory (TDDFT) can model highly complex molecules like azobenzenes accurately, effi...

One way to characterize and understand H I-selected galaxies is to study their metallicity properties. In particular, we show that the metallicity of absorbers is a bivariate function of the H I column density (NH I) and the Mg II equivalent width (W λ2796 r ). Thus, a selection upon W r is not equivalent to a H I selection for intervening absorbers. A direct consequence for damped absorbers wi...

We use the observed number and column-density distributions of intergalactic O VI absorbers to constrain the distribution of metals in the low-redshift intergalactic medium (IGM). In this simple model the metals in the O VI absorbers are assumed to be produced in and propagated from lowredshift galaxies drawn from a real sample, in this case the Sloan Digital Sky Survey (SDSS). This model can e...

With wood regaining substantial interest as a construction material due to sustainability concerns and aesthetics trends, efficient safe protection methods are needed prevent the discouloration loss of mechanical properties this renewable UV-sensitive material. In study, sustainable coatings comprising 0 20 wt% biocarbon (BC) dispersed in tung oil were developed for protection. BC particles add...

We calculate theoretical population ratios of the ground fine-structure levels of some atoms/ions which typically exhibit UV lines in the spectra of QSO absorbers redward the Ly-α forest: C, C, O, Si and Fe. The most reliable atomic data available is employed and a variety of excitation mechanisms considered: collisions with several particles in the medium, direct excitation by photons from the...

The so-called unknown absorber in the clouds of Venus is an important solar energy, but its vertical distribution remains poorly quantified. We analyze 283 and 365 nm phase curves disk-integrated albedo measured by Akatsuki. Based on our models, we find that can exist either well mixed over entire upper cloud or within a thin layer. necessary condition to explain curve must absorb efficiently s...

Using high-resolution ultraviolet spectra of 16 low−z QSOs obtained with the E140M echelle mode of the Space Telescope Imaging Spectrograph, we study the physical conditions and statistics of O VI absorption in the intergalactic medium (IGM) at z < 0.5. We identify 51 intervening (zabs ≪ zQSO) O VI systems comprised of 77 individual components, and we find 14 “proximate” systems (zabs ≈ zQSO) c...