mesoporous tio2 has been prepared using a nonionic block copolymer (pluronic p-123) as structure-directing agent with sol-gel method. characterization of the product was carried out by means of x-ray diffraction (xrd), scanning electron microscopy (sem), thermogravimetry-differential scanning calorimetry (tg-dsc), nitrogen sorption isotherms, and uv-vis absorption spectroscopy. these analyses s...

In this paper, the photochemical degradation of azure-b by Cu2+/S2O82− process has beenpresented. Cu2+ as photocatalyst and S2O82− ion as photooxidant used in this process. Atextremely low concentrations, cupric ion showed true catalytic activity in the overall process.The influence of various parameters on the performance of the treatment process has beenconsidered, such as pH, concentration o...

the resource intensive human activities (such as mining and extraction of mineral oils for betterment of life and modernization of society) have increased environmental pollution several folds. products of mining and petrochemical industries are advantageous for the modern society. but waste generated such as btex from such industries are carcinogenic, toxic and causes adverse effects on enviro...

When a nematic liquid crystal is doped with a large amount of a liquid crystalline azobenzene compound (15 wt %), the photoisomerization of azobenzene under UV and visible light irradiation can give rise to reversible and interconvertible photochemical phase transition and photochemical phase separation. Both normal and reverse modes of photocontrolled switching of transmittance through crossed...

Introduction Blue light is a part of the spectrum with the highest energy content, which can reach the retina. The damage that it can cause to the retina is called photochemical or blue-light retinal injury. For the retinal injury assessment of the photochemical and aphakic retinal hazards in the wavelength range of 300-700 nm, use of effective spectral radiance limits (W.m-2.sr-1) seems to be ...

Metal doped TiO2 catalysts were synthesized by sol-gel method and their activities were determined for degradation of methyl orang as a pollutant. Nd-doped TiO2 showed the maximum activity comparing with others. Colloidal SiO2 was used as a support to increase the surface area and also the activity. Nano-TiO2/SiO2/Nd was synthesized by sol-gel method and it was characterized using XRD, XRF, SEM...

The Hill reaction is one of the simplest chloroplast reactions in which one can measure in unambiguous terms both the reducing and the oxidizing equivalents produced in the process of photosyntnesis. In its simplest aspect, the oxidizing power is measured as oxygen production, while the reducing power is measured in terms of reduction of some electron acceptor (9). Two other photochemical react...

The direct reaction kinetic method of low pressure fast discharge flow (DF) with resonance fluorescence monitoring of OH (RF) has been applied to determine rate coefficients for the overall reactions OH + C2H5F (EtF) (1) and OH + CH3C(O)F (AcF) (2). Acetyl fluoride reacts slowly with the hydroxyl radical, the rate coefficient at laboratory temperature is k2(300 K) = (0.74 ± 0.05) × 10(-14) cm(3...

Introduction Blue light is a part of the spectrum with the highest energy content, which can reach the retina. The damage that it can cause to the retina is called photochemical or blue-light retinal injury. For the retinal injury assessment of the photochemical and aphakic retinal hazards in the wavelength range of 300-700 nm, use of effective spectral radiance limits (W.m-2.sr-1) seems to be...

This paper is presented to make both ocular symptoms and signs clear, by means of some experiments on the eye affected by photochemical air pollution. This paper summarizes three experiments, these results and discussion. The first series of experiments were performed in order to research eye irritation caused by photochemical synthetic irritants. They proved the threshold of eye irritation and...