Effects of Temperature on Mucuna solannie Water-Based Mud Properties

Water-based mud formulated from Mucuna solannie seeds, a leguminous plant, has been proved to be efficient and cost effective. Hence, the effects of temperature on the properties of the mud formulated from Mucuna solannie have been shown to follow similar trend as other mud formulations-water or oil based. Properties at temperatures of 95oF, 120oF and 180oF gave decreased values of Plastic Viscosity, Yield Point, Low Shear Rate Yield Point and Apparent Viscosity with increase in temperature, while an increase in Fluid Loss was recorded with temperature increase for both unweighted and weighted muds. Mud properties at temperature up to 212oF and above should not be found without a corresponding increase in mud pressure to prevent boiling

Enhancing the Effectiveness of Vertical Water Injection Wells With Inflow Control Devices (ICDs): Design, Simulation and Economics

Water injector completion techniques used traditionally, such as frac packs or openhole standalone screens, were judged to be incapable of meeting all completion objectives and have been reported to loose injectivity over time coupled with the issue of long term injection conformance due to plugging. Another major challenge is to achieve even distribution of the injected water into all zones along the wellbore. Permeability contrasts, formation damage, creation of thief fractures, and changes in wellbore injectivity need to be managed to avoid early breakthrough in adjacent production wells. This study presents the application of inflow control devices (ICDs), fined tuned by reservoir simulations for balancing the water injection profile into various sand formation zones in an open–hole completed injector well in Flo-Z6, a stratified Niger Delta reservoir with communicating layers.The solution targeted at developing a screening tool for deciding candidate layers in Flo-Z6 reservoir and installing special flow control devices, tailor-made for injection wells and with correct nozzle sizes for this particular case.The results from this study show that, the installation of ICDs with different nozzle configuration in the injector wells tailored to equalize the water outflow (for better sweep efficiency), improved the field oil recovery by 11.9% (6.6MMstb). Economic indicators used to validate the profitability of the investment further showed that completing the injectors with different ICD nozzle configuration was more profitable, with an NPV@10% of $192.5million, profit per dollar invested of$6.6, DCF-ROR of 81% and a pay-out period of 1.2 year which is relatively short

Low Salinity Waterflooding; A Promising Prospect to Improve Oil Recovery in the Niger Delta Oil Fields

Low salinity waterflooding is considered one of the most promising and cost–effective methods in oil recovery as a result of wettability change from oil-wet to water-wet. This work considered reducing the residual oil saturation by injection of low salt concentration in order to improve oil recovery. The objective of the study is to reduce the residual oil saturation. In this study, Simulation has been carried out on a synthetic model by using (ECLIPSE 100) as the simulator. Different Salinities of 500ppm,1000ppm, 1500ppm, 2000ppm, 5000ppm, 7000ppm, 10000ppm,30000ppm and 40000ppm were evaluated. Low salinity water was injected at the first year of production and continues to the end of the production life.Effect of salinity on oil recovery was also evaluated. The results obtained showed that low salinity waterflooding improved oil recovery at different salinity as compared to fresh water waterflooding. In conclusion, based on the results of this work, it is possible to choose the best salinity ratio that gives the lowest residual oil saturation

Genetic and pharmacological modulation of the steroid sulfatase axis improves response control; comparison to drugs used in ADHD

Maladaptive response control is a feature of many neuropsychiatric conditions, including Attention Deficit Hyperactivity Disorder (ADHD). As ADHD is more commonly diagnosed in males than females, a pathogenic role for sex-linked genes has been suggested. Deletion or point mutation of the X-linked STS gene, encoding the enzyme steroid sulfatase influences risk for ADHD. We examined whether deletion of the Sts gene in the 39,XY*O mouse model, or pharmacological manipulation of the steroid sulfatase axis, via administration of the enzyme substrate dehydroepiandrosterone sulfate or the enzyme inhibitor COUMATE, influenced behavior in a novel murine analogue of the stop-signal reaction time task used to detect inhibitory deficits in individuals with ADHD. Unexpectedly, both the genetic and pharmacological treatments resulted in enhanced response control, manifest as highly specific effects in the ability to cancel a pre-potent action. For all three manipulations, the effect size was comparable to that seen with the commonly used ADHD therapeutics methylphenidate and atomoxetine. Hence, converging genetic and pharmacological evidence indicate that the steroid sulfatase axis is involved in inhibitory processes and can be manipulated to give rise to improvements in response control. Whilst the precise neurobiological mechanism(s) underlying the effects remain to be established, there is the potential for exploiting this pathway in the treatment of disorders where failures in behavioral inhibition are prominent

Deficiency in the Multicopy Sycp3-Like X-Linked Genes Slx and Slxl1 Causes Major Defects in Spermatid Differentiation

Slx and Slxl1 are genes present in multiple copies on the mouse X chromosome. Using transgenically-delivered small interfering RNAs to disrupt their function, we show that Slx and Slxl1 are important for normal sperm differentiation and male fertility

Vulnerability Assessment of Power Grid Using Graph Topological Indices

This paper presents an assessment of the vulnerability of the power grid to blackout using graph topological indexes. Based on a FERC 715 report and the outage reports, the cascading faults of summer WSCC 1996 are reconstructed, and the graphical property of the grid is compared between two cases: when the blackout triggering lines are removed simulating the actual sequence of cascading outages and when the same number of randomly selected lines are removed. The investigation finds that the critical path lengths of the triggering events of the July and August outages of 1996 WSCC blackout are higher than those of no-outage and arbitrary events. In addition, the small world-ness index for each of the outage triggering events is much smaller than that of normal or any no-outage scenario, indicating that events of shifting a network from small world to a random network would be more likely cascaded to wide area outage