The present paper has determined the radioactivity concentrations, which are due to natural occurrence of radionuclides along with heavy metal concentration in water, sediment, and fish from 2 reservoirs in Ghana. Heavy metal concentrations in all samples were generally within the WHO safe limits with the average activity concentrations of 238U, 232Th, and 40K in water being respectively 0.42±0...

    The combination of horizontal drilling along with hydraulic fracturing has significantly improved the production of hydrocarbon reservoirs and made it possible to extract the relatively impermeable and uneconomical reservoirs. The production rate of oil and gas wells increases proportional to hydraulic fracture aperture or crack opening displacement (COD). This is an important parameter i...

Reservoirs exhibit gradients in conditions and resources along the transition from lotic to lentic habitat that may be important to bluegill ecology. The lotic-lentic gradient can be partitioned into three functional zones: the riverine, transitional, and lacustrine zones. We measured catch frequency and length of bluegills (Lepomis macrochirus) captured along the periphery of these areas (i.e....

Abstract This paper presents a spill-minimizing operating policy for refill of reservoirs in parallel for water supply considering water quality criteria. First a Linear Programming form of the New York City Rule is developed. Next, this formulation is extended to consider stratified water quality in the reservoirs and a requirement of water quality for the downstream demand. Both approaches ar...

rough sets theory is a mathematical approach for analysis of a vague description of objects presented by a well-known mathematician, pawlak (1982, 1991). this paper explores the use of rough sets theory in site location investigation of buried concrete water reservoirs. making an appropriate decision in site location can always avoid unnecessary expensive costs which is very important in constr...

Emission of methane (CH4), a potent greenhouse gas, from tropical reservoirs is of interest because such reservoirs experience conducive conditions for CH4 production through anaerobic microbial activities. It has been suggested that Indian reservoirs have the potential to emit as much as 33.5 MT of CH4 per annum to the atmosphere. However, this estimate is based on assumptions rather than actu...

Open systems are usually understood as a small Hamiltonian system (i.e. with a finite number of degrees of freedom) in contact with one or several large reservoirs. There are several ways to model reservoirs and we will take the point of view that the reservoirs are also Hamiltonian systems themselves. It is a convenient physical and mathematical idealization to separate scales and assume that ...

A lot of oil and gas reservoirs have been or will be abandoned in petroleum industry. In this study, we pointed out that these oil and gas reservoirs might be transferred into exceptional enhanced geothermal reservoirs with very high temperatures by oxidizing the residual oil with injected air. A concept to generate power from these exceptional enhanced geothermal reservoirs by using geothermal...

The historical and ongoing lead (Pb) contamination caused by the 20th-century use of leaded gasoline was investigated by an analysis of bottom sediment in eight small rural reservoirs in eastern Kansas, USA. For the reservoirs that were completed before or during the period of maximum Pb emissions from vehicles (i.e., the 1940s through the early 1980s) and that had a major highway in the basin,...

Water-flooded oil reservoirs have specific ecological environments due to continual water injection and oil production and water recycling. Using 16S rRNA gene clone library analysis, the microbial communities present in injected waters and produced waters from four typical water-flooded oil reservoirs with different in situ temperatures of 25 °C, 40 °C, 55 °C and 70 °C were examined. The resul...