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641.
The reservoir properties of three wells in Royal Field, Niger Delta basin was characterized using fundamental formula. The distributions and thicknesses of sand bodies were determined within each of the wells in the field using geophysical modeling software. The quantitative and qualitative analyses were done for the three exploration wells with the depth ranges of 4000-9700m for Royal well 1, 1000-8805m for Royal well 2, and 4000-8000m for Royal well 3. Each well has identified sand units. Royal well 1 and Royal well 2 have 5 sand units (A, B, C, D, E) each, with respective thicknesses 422m, 110m, 92m, 142m and 350m for well 1, and 82m, 65m, 214m, 362m, and 192m for well 2. Royal well 3 has 4 sand units (A, B, C, D), with respective thicknesses 135m, 80m, 269m and 229m. Petrophysical evaluations were made from well logs. The average porosity values obtained for Royal wells 1, 2, and 3 are 0.24, 0.18 and 0.22 respectively while the corresponding average permeability values are 2789mD, 1292mD, 1643mD. Porosity values obtained from porosity logs and density log (RHOB) using porosity formula are found to be within the range of 0.07- 0.45, while their permeabilities range from 164 to 8453 milli Darcy. The water saturation obtained for each reservoir unit in combination with the resistivity index were used to prove the presence of hydrocarbon in these sands. Royal well 2 having its sand A, 80% hydrocarbon saturated and 82m thickness is the most prolific. The results clearly indicate that the application of this technique is very effective for the interpretation of reservoir properties.  相似文献   
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The state-of-the-art monitoring of drinking water hygiene is based on the cultivation and enumeration of indicator bacteria. Despite its proven reliability, this approach has the disadvantages of being (a) relatively slow and (b) limited to a small number of indicator bacteria. Ideally, alternative methods would be less time-consuming while providing information about a larger set of hygienically relevant microorganisms including viruses. In this paper, we present insights into the design of a modular concentration and detection system for bacteria, bacteriophages and viruses. Following further validation, this or similar techniques have the potential to extend and speed up the monitoring of raw and drinking water hygiene in the future. The system consists of different modules for the concentration of microorganisms, an amplification and detection unit that includes a module for the differentiation between live and dead microorganisms, and an automated system for decision support and self-diagnosis. The ongoing testing under controlled laboratory conditions and real-life conditions in the water supply industry yields further system improvements. Moreover, the increased sensitivity and broader range of microbiological parameters emphasize the need for a reconsideration of the currently used criteria for the assessment of (drinking) water hygiene.  相似文献   
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