The crystallinity of cadmium titanate (CdTiO3) was greatly improved when synthesized under mild reaction conditions, in the presence of chloride. The highly crystalline CdTiO3 showed much enhanced photodegradation of methyl orange (MO) under simulated sunlight. CdTiO3 was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS),...

The photodegradation of pesticides is reviewed, with particular reference to the studies that describe the mechanisms of the processes involved, the nature of reactive intermediates and final products. Potential use of photochemical processes in advanced oxidation methods for water treatment is also discussed. Processes considered include direct photolysis leading to homolysis or heterolysis of...

We report a comparative study on the photodegradation of the widely used benzodiazepine psychoactive drug alprazolam (8-chloro-1-methyl-6-phenyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepine, ALP) using direct photolysis, and titanium dioxide photocatalyzed reaction. Titanium dioxide photocatalysts were prepared as nanoparticles by acidic sol-gel methods, calcined at two different temperatures, ...

A multivariate kinetic model of aqueous fipronil photodegradation was developed as a function of dissolved organic matter (DOM), bicarbonate, and nitrate at concentrations that bracketthose commonly observed in natural waters (ca. 0-10 mg/L). Several pathways were available for fipronil photodegradation in this system, including direct photolysis and indirect photooxidation by species produced ...

The present paper demonstrates the increased photostability of isotretinoin when loaded in microemulsion. The photodegradation of isotretinoin, in methanol and microemulsion formulation was studied under direct sun light. The photodegradation process was monitored by UV spectrophotometry. In methanol solution, isotretinoin undergoes complete photodegradation just within a few minutes of light e...

The photodegradation of two organophosphorus pesticides, malathian and diazinon, by sulfate radicals and bicarbonate radicals in aqueous solution were studied. The effect of the operational parameters such as pH, salt concentration, water type, H2O2 concentration and initial concentration of pesticides was studied. Gas chromatography mass spectroscopy (GC-MS) was used for analyses of pesticides...

In this review, we demonstrate a real-time time-frequency two-dimensional (2D) pump-probe imaging spectroscopy implemented on a single shot basis applicable to excited-state dynamics in solid-state organic and biological materials. Using this technique, we could successfully map ultrafast time-frequency 2D transient absorption signals of β-carotene in solid films with wide temporal and spectral...

A mild acidic dioxane extraction method was employed to isolate lignin from hardwood bleached chemimechanical pulp (BCMP). The isolated lignin was then purified and undergone elemental analysis. To study the photodegradation behavior, the lignin samples were impregnated onto the Whatman filter papers and irradiated with UV light for various periods. The photolyzed lignin was then recovered and ...

The advance of 157 nm as the next photolithographic wavelength has created a need to for transparent and radiation durable polymers for the use as pellicles. The most promising materials for the pellicles are fluorinated polymers, but the currently available fluorinated polymers undergo photodegradation and/or photodarkening upon exposure to 157 nm irradiation. To understand the mechanism of th...

We evaluated the acute toxicity of zinc pyrithione and copper pyrithione, used as antifouling booster biocides, and their six main photodegradation products to three marine organisms, representing three trophic levels: an alga (Skeletonema costatum), a crustacean (Tigriopus japonicus), and a fish (Pagrus major). The acute toxicity values of the pyrithiones for S. costatum, T. japonicus, and P. ...