conclusions the uv/zno system has been found an effective process with 90.2% cod removal and 95.6% dye removal after 50 minutes treatment. materials and methods in this work, zno catalyst and mercury lamp (uv-c, 254 nm) have been applied for removal of the c.i. sulphur red 14 dye from aqueous environments. the influence of various parameters such as the amount of zno, initial dye concentration,...

Abstract UV photolysis and UV based advanced oxidation processes (AOPs) are gaining more and more attention for drinking water treatment. Quantum yield (f) and molar absorption coefficient (ε) are the two critical parameters measuring the effectiveness of photolysis of a compound. The product of the two was proposed as a fundamental measure of a constituent’s amenability to transformation by ph...

The formation of HCO and of H in the photolysis of glyoxal have been investigated over the wavelength ranges 310-335 nm for HCO and 193-340 nm for H. Dye laser photolysis was coupled with cavity ring-down spectroscopy for HCO, and with laser induced fluorescence spectroscopy for H. Absolute quantum yields were determined using actinometers based on (a) Cl2 photolysis and the Cl + HCHO reaction ...

Positionally dependent fractionation factors for the photolysis of isotopomers of N20 in natural abundance have been determined by high resolution FTIR spectroscopy at three photolysis wavelengths. Fractionation factors show clear lSN position and photolysis wavelength dependence and are in qualitative agreement with theoretical models but are twice as large. The fractionation factors increase ...

Motivated by Yung and Miller’s suggestion [1997] that N2O is isotopically fractionated during UV photolysis in the stratosphere, we have studied the photolysis rates of the NNO and NNO structural isotopomers. In this study, we follow the concentrations of these compounds with FTIR spectroscopy during photolysis at 213 nm. Our results show that, as Yung and Miller predicted, the photolysis rate ...

An established synchronous solid surface fluorimetry (S-SSF) was utilized for in situ study the photolysis processes of anthracene (An) and pyrene (Py) adsorbed on the leaf surfaces of Kandelia obovata seedlings (Ko) and Aegiceras corniculata (L.) Blanco seedlings (Ac). Experimental results demonstrated that the photolysis of An and Py adsorbed on the leaf surfaces of two mangrove species under...

The effect of aerosols on 14 tropospheric photolysis reactions is examined under noncloudy and cloudy sky conditions by using a detailed one-dimensional radiative transfer model. Pure (NH4)2SO4, pure soot, and internal and external mixtures of the two aerosols, as well as mineral dust aerosol, are considered. Nonabsorbing aerosol generally enhances photolysis rates above and in the upper part o...