Galctose oxidase nanoaggregates have been prepared by chemical desolvation method involving the crosslinkng agent glutaraldehyde. These enzyme nanoagregates have been characterized by transmission electron microscopy(TEM), UV visible spectroscopy, Fourier transform infrared spectroscopy (FTIR). TEM reveals the globular spherical nanostructured form upto the range of 20nm. UV visible spectroscop...

Five different combinations of fluorescent tubes (UV-B/UV-B, UV-B/UV-A, UV-A/ UV-A, UV-B/White, White/White) were used to determine relative effects of UV and visible light on the nucleopolyhedroviruses (NPV) of Helicoverpa zea and Spodoptera exigua. For both viruses, the greatest inactivation occurred with exposure to UV-B radiation. Both virus concentration and radiation exposure time influen...

The photocatalytic activity of meso-tetraphenylporphyrins with different metal centers (Fe, Co, Mn and Cu) adsorbed on TiO(2) (Degussa P25) surface has been investigated by carrying out the photodegradation of methyl orange (MO) under visible and ultraviolet light irradiation. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectan...

TiO2 nanotube arrays are well-known efficient UV-driven photocatalysts. The incorporation of graphene quantum dots could extend the photo-response of the nanotubes to the visible-light range. Graphene quantum dot-sensitized TiO2 nanotube arrays were synthesized by covalently coupling these two materials. The product was characterized by Fourier-transform infrared spectrometry (FTIR), scanning e...

Today octocrylene is one of the most common molecules included in commercially available sunscreens. It provides broadband photoprotection for the skin from incident UV-A and UV-B radiation of the solar spectrum. In order to understand how octocrylene fulfils its role as a sunscreening agent, femtosecond pump-probe transient electronic UV-visible absorption spectroscopy is utilised to investiga...

We have used UV (FOCA) and FIR (IRAS) images of six nearby late type galaxies to study the radial variation of the UV extinction (deduced from the FIR/UV ratio). We compare the UV extinction gradient with other extinction indicators (Balmer decrement) and search for a relation between the extinction, the metallicity and the gas surface density among our galaxies. We detect in our small sample a...

In this work, the structural properties and spectroscopic behavior 80 mol.%TeO2-20mol.%LiF glasses which were doped with 0. 05, 0. 2 mole% Gd2O3 have been studied. It was shown that,  by increasing the amount of Gd2O3 the glass stability was decreased. The PL emissions at 431nm and 627nm wavelengths were distinguished by 320nm excitation. The FT-IR analysis showed deformed TeO4 groups in these ...

Christina Hsu Goddard Earth Sciences and Technology Center University of Maryland Baltimore County NASA/Code 916 Greenbelt, Maryland 20771 Abstract. Satellite instruments currently provide global maps of surface UV irradiance by combining backscattered radiance data with radiative transfer models. The models are often limited by uncertainties in physical input parameters of the atmosphere and s...

A novel class of azo-guanidine compounds is introduced in this article. The novel compound 2-(2-hydroxyphenyl)-1-(phenylamino)-3-(phenylimino)guanidine (AG) was synthesized and well characterized by using different analytical instrumental techniques like elemental analysis, FTIR, (1)H and (13)C NMR, UV-Visible spectroscopy and cyclic voltammetry. The new compound was found interacting with DNA ...