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Wind power is not only pollution free and renewable but is becoming more economical with technology development. The countries around the Arabian Gulf region are investing for wind powers both the land and in their marine space. A detailed study on wind power resource in the Arabian Gulf is not available. This paper is on the wind energy resource availability over Arabian Gulf waters, covering 2300 grid points. The data available with Coastal Information System data base at Kuwait Institute for Scientific Research, Kuwait, from 1979 to 2015 is used. The probability density and power density were derived from these data source. Weibull probability density function has been fitted to the wind speed data and the wind power density was evaluated. The study is carried out at 10 m, 30 m and 50 m elevations. The central location of the Arabian Gulf has higher annual average wind speed, ranging from 6 to 8 m/s at 10 m elevation, 7 to 8 m/s at 30 m elevation and 8 to 9 m/s at 50 m elevation. The scale parameter "c" at central location of Arabian Gulf is found to range from 6-8 m/s for 10 m elevation, 7-8 m/s for 30 m elevation and 8-9 m/s for 50 m above sea level. The Weibull shape parameter k varies from 2.5 to 3 at the north and central of the Arabian Gulf. The annual mean wind power density over Arabian Gulf Waters is the highest in the central region of the Gulf. The power density at 10 m, 30 m and 50 m hub height varies between 200 to 300 w/m 2 , 200 to 300 w/m 2 and more than 300 w/m 2 respectively. It is attractive to install large scale wind power generation at the central region of the Arabian Gulf and at elevations of 30 m or 50 m, since this region lies in Class 2 category of the Wind Energy Resource Atlas of the United States. The wind power density is attractive especially in summer season around the central region location in Arabian Gulf (Saudi Arabia, Bahrain and Qatar), since high rate of power is used for air conditioning systems in summer.

The levels of hydrological pollution of Chennai coastal zone in the southeastern part of India have been increased in the recent years by an uncontrolled disposal of wastewater and pollutants due to human activities. This study gave a special emphasis on the determination of the levels of pollution, the identification of vulnerable zones and providing some probable remedial measures for severely impacted coastal zone of Chennai city. During the period from September to November 2002, sampling was carried out along the shore in two traverses running in the seaside (surf zone) and landside (coastal aquifer). When sampling efforts took place the middle of the above period experienced a monsoonal storm over Chennai coast that significantly influenced large variations in the pollution level at both traverses in seaside and landside. Analysis of physical, chemical and biological parameter determinations indicated that the concentrations of dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), nutrients (nitrate, nitrite and phosphate), turbidity, maximum probable number (MPN) and chlorophyll a (Chl a) reached notably high levels at all sample locations before monsoonal storm prevailed over these areas during October 2002, which resulted in large fresh water input to the coastal system reducing the levels of pollution to some extent. Analysis of water samples collected during November apparently indicated Springer 1188 Water Resour Manage (2007) 21: [1187][1188][1189][1190][1191][1192][1193][1194][1195][1196][1197][1198][1199][1200][1201][1202][1203][1204][1205][1206] that the concentrations of above parameters attained abnormal level and often exceeded the permissible limit of international standards. The concentrations of trace/toxic metals such as manganese, copper, nickel, lead, cadmium and cobalt also reached very high levels as a result of their sub-aqueous disposal to these areas, leading to further habitat and ecological destruction. On the other hand, analysis of groundwater samples collected from coastal aquifer for determination of certain chemical parameters such as Ca 2+ /Mg 2+ , Cl − /(CO 2− 3 +HCO − 3 ) and the ratio of total alkalinity (TA) and total hardness (TH) revealed that coastal groundwater appeared to be severely contaminated by saltwater intrusion as a result of overexploitation and enormous pressure imposed by monsoonal storm of October. Higher concentrations of toxic elements, for example, lead, nickel, cobalt and cadmium from the influence of industrial wastes and contaminated coastal waters, were also found to deteriorate the quality of coastal aquifer system. Based on detailed examination, four sites including Cuvum estuary, Adyar estuary, Kannikoil and Bharathiyar nagar are identified as highly venerable zones because of receiving a large quantity of municipal and industrial wastes. To reduce severe pollution levels in these areas it is therefore necessary to design and construct the submarine pipeline system to transport and disperse such a large quantity o...

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Graphene oxide (GO) nanosheets modified with zinc oxide nanocrystals were achieved by a green wet-chemical approach. As-obtained products were characterized by XRD, Raman spectra, XPS, HR-TEM, EDS, PL and Photocatalytic studies. XRD studies indicate that the GO nanosheet have the same crystal structure found in hexagonal form of ZnO . The enhanced Raman spectrum of 2D bands confirmed formation of single layer graphene oxides. The gradual photocatalytic reduction of the GO nanosheet in the GO : ZnO suspension of ethanol was studied by using X-ray photoelectron (XPS) spectroscopy. The nanoscale structures were observed and confirmed using high resolution transmission electron microscopy (HR-TEM). The evolution of the elemental composition, especially the various numbers of layers were determined from energy dispersive X-ray spectra (EDS). PL properties of GO : ZnO nanosheet were found to be dependent on the growth condition and the resultant morphology revealed that GO nanosheet were highly transparent in the visible region. The photocatalytic performance of GO : ZnO nanocomposites was performed under UV irradiation. Therefore, the ZnO nanocrystals in the GO : ZnO composite could be applied in gradual chemical reduction and consequently tuning the electrical conductivity of the graphene oxide nanosheet.

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