Heterogeneous photo-Fenton decolorization of Orange II over Al-pillared Fe-smectite: response surface approach, degradation pathway, and toxicity evaluation.

A ferric smectite clay material was synthesized and further intercalated with Al2O3 pillars for the first time with the aim of evaluating its ability to be used as heterogeneous catalyst for the photo-Fenton decolorization of azo dye Orange II. UV irradiation was found to enhance the activity of the catalyst in the heterogeneous photo-Fenton process. Catalyst loading of 0.

Long-exposure filtering of turbulence-degraded wavefronts.

The quasi-static aberrations of optical telescopes are often determined using light from a star as the reference wavefront. We calculate the exposure time necessary to determine the amplitude of the phase aberrations for a given telescope to a given accuracy in the presence of atmospheric seeing. We implement a computational simulation of the atmosphere and present the root mean square of the generated wavefront Zernike amplitudes for a given exposure time.

Infrared images of the transiting disk in the epsilon Aurigae system.

Epsilon Aurigae (epsilon Aur) is a visually bright, eclipsing binary star system with a period of 27.1 years. The cause of each 18-month-long eclipse has been a subject of controversy for nearly 190 years because the companion has hitherto been undetectable.

Unambiguous phase retrieval as a cophasing sensor for phased array telescopes.

Cophasing a multiple-aperture optical telescope (MAOT) or optical interferometer requires the knowledge of the tips/tilts and of the differential pistons on its subapertures. In this paper we demonstrate in the case of a point source object that a single focal-plane image is sufficient for MAOT cophasing. Adopting a least-square approach allows us to derive an analytic estimator of the subaperture aberrations, provided that these are small enough (typically for closed-loop operation) and that the pupil is diluted noncentrosymmetric.