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Photocatalysis process, as an environmental application, is a relatively novel subject with tremendous potential in the near future. A number of studies determine the economic viability of applying various ultraviolet advanced oxidation processes for the purpose of degradation and destroying of various pollutant solutions. The present paper reviews the treatment of hazardous wastewater bearing organic compounds and the effects of various parameters such as pH, initial concentration, mass of catalyst, wavelength, light intensity, electron acceptor, temperature, etc., with the treatment cost for different reactor type. This study investigates the effect of various types of waste-water treatment parameters and the treatment cost for various designs of photocatalytic reactors, using both solar and artificial light, have been proposed for their different types of pollutants.

In the present study, solar photocatalytic oxidation has been investigated through laboratory experiments as an alternative to conventional secondary treatment for the organic content reduction of high COD wastewater. Experiments have been performed on synthetic high COD wastewater for solar photocatalytic oxidation using a parabolic trough reactor. Parameters affecting the oxidation of organics have been investigated.The experimental design followed the sequence of dark adsorption studies of organics, followed by photolytic studies (in absence of catalyst) and finally photocatalytic studies in presence and absence of additional oxidant (H2O2). All the experimental studies have been performed at pH values of 2, 4, 6,8,10 and the initial pH value of the wastewater (normal pH). For photocatalytic studies, TiO2 has been used as a photocatalyst. Optimization of catalyst dose, pH and H2O2 concentration has been done. Maximum reduction of organic content was observed at the normal pH value of the wastewater (pH = 6.8). The reaction rate was significantly enhanced in presence of hydrogen peroxide. The optimum pH other than the Normal was in the alkaline range. Acidic pH was not found to be favourable for organic content reduction. pH was found to be a dominant factor affecting reaction rate even in presence of H2O2 as an additional oxidant. Also, the solar detoxification process was effective in treating a waste with a COD level of more than 7500 mg/L, which is a otherwise a difficult waste to treat. It can therefore be used as a treatment step in the high organic wastewater treatment during the primary stage also as it effectively reduces the COD content by 86%.

Thorium is surprisingly abundant in the Earth's crust, being almost as abundant as lead and three times more abundant than uranium. It is found in small amounts in most rocks and soils. Granitile contains up to 80 ppm of thorium. Thorium occurs naturally as the minerals thorite, uranothorite, and thorianite. It is a major component of monazite and it is present in significant amounts in the minerals zircon, titanite, gadolinite and betafite. The amounts of thorium in the environment may be incidentally increased due to accidental releases of thorium processing plants. Uncontrolled large amounts of thorium may be found near hazardous waste sites where thorium has not been disposed of according to the proper procedures. People living near these sites may get exposed to more thorium as they breathe in windblown dust and because it ends up in food that is grown near the site.Since thorium has the ability to change genetic arrangements, it may increase the chances of developing the lung diseases and pancreas cancer. 1 Therefore, more efforts are required to develop ion-selective electrodes of commercial standards for heavy metal ions that are toxic beyond a certain concentration level. 2A literature survey showed that only three-potentiometric electrodes are available for detecting and/or measuring and monitoring thorium in environmental media. 3-5The present work describes the working of a sensor involving a dithio-tetraaza macrocyclic compound, namely 2,3,7,8-tetraphenyl-1,4,6,9-tetraaza-cyclodeca-5,10-dithion-1,3,6,8-tetraene (TPTACDTT) as ionophore, 3% sodium tetraphenyl borate (NaTPB) as an additive and 62% nitrobenzene (NB) as a plasticizing solvent mediator for thorium(IV) ions. This novel Th 4+ -selective electrode not only possesses the advantages of the simplicity of the design in membrane preparation but also has a fast response time, good linear range and detection limit and high selectivity over a variety of various metal ions; in many respects the values are better than those reported in the literature. 3-5 Experimental Reagents and chemicalsReagent grade benzyl acetate (BA), nitrobenzene (NB), sodium tetraphenyl borate (NaTPB), tetrahydrofuran (THF) and high relative molecular weight PVC (all from Merck and Aldrich) were used as received. The nitrate and chloride salts of all cations used (all from Merck and Aldrich) were of the highest purity available and were used without any further purification except for vacuum drying over P2O5. Doubly distilled deionized water was used throughout. Synthesis of ionophore TPTACDTTTo a hot ethanolic solution (50 ml) of benzil (0.093 M, 6.3 g) acidified with 0.5 ml conc. HCl, a hot ethanolic solution (50 ml) of thiourea (0.03 M >2.28 g approx.) was added drop-wise with stirring. Then the reaction mixture was refluxed at 60˚C for more than 12 h. The reaction mixture was kept in a cool place for 24 h and finally a light greenish yellow, bright crystalline compound was obtained. This was filtered on a buchner funnel using a suction pump, followed by washing with EtOH a...

The issue regarding why corporate enterprises engage in mergers and acquisitions (M&As) has become the centre of a large body of corporate finance literature in recent years. In the Indian context, the deregulated policy regime started in 1991 has significantly contributed to the increase in M&A activity. This paper is aimed at examining the long-term impact following M&As of listed Indian enterprises in the post-liberalisation period by using financial accounting data. Throughout the period of study, turnover increased after the companies experienced an M&A which is in line with the findings that Indian companies grew in size and attained bigger market share. M&As did not have any impact on return on net worth for the period of study. Mixed results have been reported for other variables.