Flow coupling during three-phase gravity drainage

We measure the three-phase oil relative permeability k(ro) by conducting unsteady-state drainage experiments in a 0.8 m water-wet sand pack. We find that when starting from capillary-trapped oil, k(ro) shows a strong dependence on both the flow of water and the water saturation and a weak dependence on oil saturation, contrary to most models. The observed flow coupling between water and oil is stronger in three-phase flow than two-phase flow, and cannot be observed in steady-state measurements. The results suggest that the oil is transported through moving gas-oil-water interfaces (form drag) or momentum transport across stationary interfaces (friction drag). We present a simple model of friction drag which compares favorably to the experimental data.University of Texas at AustinCenter for Frontiers of Subsurface Energy SecurityUS Department of Energy, Office of Basic Energy Sciences DE-SC0001114Petroleum and Geosystems Engineerin

Generation of Al Nanoparticles via Laser Ablation in Deionized Water with Structural and Morphological Study

In this work, Al nanoparticles were generated using Pulsed Nd : YAG laser (1064 nm) ablation in water confined plasma. Productions were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and selected area electron diffraction (SAED). Laser ablation of the Al target in deionized water leads to fabrication core-shell type structure due to partial oxidation in the water medium. The Nano sized core-shells are spherical in shape and have mean size ~ 16 nm. NPs were in the crystalline form as bulk Al. Obviously, the chemical composition of the Nano sized core-shells surface must be Al2O3 because of water medium

Generation of Al Nanoparticles via Laser Ablation in Deionized Water with Structural and Morphological Study

In this work, Al nanoparticles were generated using Pulsed Nd : YAG laser (1064 nm) ablation in water confined plasma. Productions were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and selected area electron diffraction (SAED). Laser ablation of the Al target in deionized water leads to fabrication core-shell type structure due to partial oxidation in the water medium. The Nano sized core-shells are spherical in shape and have mean size ~ 16 nm. NPs were in the crystalline form as bulk Al. Obviously, the chemical composition of the Nano sized core-shells surface must be Al2O3 because of water medium

Germination improvement and α-amylase and β-1,3-glucanase activity in dormant and non- dormant seeds of Oregano (Origanum vulgare)

Abstract Oregano plays a primary role among temperate culinary herbs in world trade. It is native of Southern Europe and is one of the most popular herbs in Mediterranean cooking. The germination response of this species to various germination improvement treatments including mechanical, physical and chemical scarification, were studied. Mechanical and chemical scarification of seed coat improved seed germination parameters and suggesting that O. vulgare seeds have an exogenous dormancy. Moreover, seed germination of oregano affected by other treatments such as moist chilling and chemicals, and proposing that oregano seeds also have endogenous dormancy. Standard germination test showed that germination percentage of untreated seeds is 25.8% while after chilling treatment at 4 ˚C for 7 days germination percentage reached to 39%. Soaking seeds in 100 ppm of GA 3 for 36 h resulted in 48% germination. The highest value of germination parameters detected by soaking seeds in -10 bar polyethylene glycol solution at 20 ˚C for 72 h. Total germination percentage reached to 60% in this treatment. Combination of chilling and PEG improved seed germination significantly, but was not as effective as PEG solely. Enzyme activity of α-amylase and β-1,3-glucanase in germinating seeds at 12 h after start of imbibition were assayed. Dormant seeds showed lower enzyme activity and enzyme activity in treated seeds increased significantly

Hourly Price-Based Demand Response for Optimal Scheduling of Integrated Gas and Power Networks Considering Compressed Air Energy Storage

Gas-fired plants are becoming an optimal and practical choice for power generation in electricity grids due to high efficiency and less emissions. Such plants with fast start-up capability and high ramp rate are flexible in response to stochastic load variations. Meanwhile, gas system constraints affect the flexibility and participation of such units in the energy market. Compressed air energy storage (CAES) as a flexible source with high ramp rate can be an alternative solution to reduce the impact of gas system constraints on the operation cost of a power system. In addition, demand response (DR) programs are expressed as practical approaches to overcome peak-demand challenges. This study introduces a stochastic unit commitment scheme for coordinated operation of gas and power systems with CAES technology as well as application of an hourly price-based DR. The introduced model is performed on a six-bus system with a six-node gas system to verify the satisfactory performance of the model

Hydraulic conductance and viscous coupling of three-phase layers in angular capillaries

Predicting three-phase relative permeability by network models requires reliable models for hydraulic conductance of films and layers stabilized by capillary forces at the pore level. We solve the creeping flow approximation of the Navier-Stokes equation for stable wetting and intermediate layers in the corner of angular capillaries by using a continuity boundary condition at the layer interface. We find significant coupling between the condensed phases and calculate the generalized mobilities by solving cocurrent and countercurrent flow of wetting and intermediate layers. Finally, we present a simple heuristic model for the generalized mobilities as a function of the geometry and viscosity ratio.US Department of Energy, Office of Basic Energy Sciences DE-SC0001114Petroleum and Geosystems Engineerin

Evaluation of Clinical Skills of Final Year Nursing Students in Critical Care Units.

Introduction: Clinical education in critical care units is very important and promotion of quality of clinical education can lead to higher qualification and professionalism of nursing students in this area of practice . So, this study was conducted to evaluate the clinical skills of nursing students in ICU , CCU and dialysis Units . Method & Materials : This research was a cross sectional descriptive one and the samples of this research were 72 final year nursing students of Yazd Shaheed Sadoughi Nursing School. The data was collected by a demographic and checklist questionnaire about clinical skills in ICU, CCU , and dialysis unit . Analysis and descriptive statistics were used for the research goals. Results : Results showed that clinical skills of nursing students in critical care units is ideal, but these skills in CCU are lower than ICU and dialysis unit . Results indicated that the levels of the clinical skills of nursing students were directly related to their examination scores and interest in nursing . Conclusion : Our findings indicate that special attention should be paid to clinical education in critical care units and selection of students in this field should be given special attention