69 research outputs found
Variation in General Price Level in Pakistan: A Recent Evidence by Using ARDL Approach (1974-2016)
The main purpose of this study to investigate the impact of the bank rate, budget deficit, FDI and money supply M2 on inflation in the case of Pakistan applying the ARDL model using yearly data from 1974-2016. The Experimental evidence highlight that there is a unique and stable relationship among dependent variable inflation and other different explanatory variables, bank rate, budget deficit, Foreign investment, GDP, Exchange rate and trade openness. After analysis, the result of ARDL indicates that bank rate, exchange rate, and GDP have a negative impact on inflation in the long-run co-efficient. On the other hand, budget deficit, FDI, Money supply M2 and trade openness have a positive impact on inflation. These two tests CUSUM and CUSUMSQ shed light on validates and stability of coefficients in this approach
Numerical Mechanistic Study of In-Situ CO2 EOR – Kinetics and Recovery Performance analysis
The success of supercritical CO2 Enhanced Oil Recovery (EOR) cannot be duplicated if the cost of CO2 transposition and processing becomes prohibitive. Research results of the in-situ CO2 EOR (ICE) approach offered a potential technology for many waterflooded stripper wells that lack access to affordable CO2 sources. Previously the ICE synergetic mechanisms were only qualitatively attributed to oil swelling and viscosity reduction due to the preferential partition of CO2 into the oleic phase. This study aims to quantify the contributions to recovery factors from several plausible mechanisms with numerical modeling and simulation.
First, urea reaction was modeled as the CO2 generating chemical decomposing to CO2 and ammonia under the reservoir conditions. The CO2 partitions into oil, which leads to the reaction continuation to generate more CO2. The resulting ammonia largely left in water may further react with certain oil components to generate surfactant, thus decreasing the oil/water interfacial tension (IFT). It is expected that the oil containing CO2 also has a lower IFT with water. The reaction kinetics under different temperatures were incorporated into the model. A numerical model featuring the synergetic mechanisms was built, including stoichiometry and kinetics of urea reaction, oil swelling effect, oil viscosity reduction, and IFT reduction effect on the relative permeabilities. I matched previous laboratory data for three different oils including dodecane, Earlsboro oil, and DeepStar oil, the same oils used in laboratory studies. The phase behavior was modeled with the Equation of State (EOS) under different mole fractions of CO2.
The estimated reduction of oil viscosity was calculated, 79% for Earlsboro oil, 91% in DeepStar oil, and 76% in dodecane oil. The oil swelling factors ranged from 10% to 50% in the three lab models, which translate to the recovery factor of oil. Then I modified the endpoints of relative permeability to account for the recovery contribution to the IFT and viscosity reduction. The impact of reaction kinetics on oil swelling and recovery factor was also determined, and they are not numerically close to reaction kinetics which were used in the lab cases. The study concluded that the incremental recovery due to oil swelling ranges between 6.4% and 18.0%, and the from 24% to 38% is due to IFT and viscosity reduction for all the cases. The relative permeability and urea reaction kinetics remained the most uncertain parameters during history matching and modeling the ICE synergetic mechanisms. Later on, I upscaled the lab-scale model to a 3D sector model which features reaction kinetics, multi-components, and sensitivity study on selected parameters.
To my knowledge, this is the first in modeling and differentiating the individual contributions on recovery from the synergetic mechanisms of ICE. The success of this model will tremendously reduce the potential laboratory experiment efforts and significantly improve the modeling capability in field application of the ICE technology. The developed model can be easily upscaled and retrofitted for other applications such as development planning and production forecast for ICE
Synthesis of Zeolites from Coal Fly Ash and Their Environmental Application
This study aims to make adsorption-capable zeolite from coal fly ash, a waste product from coal-fired power plants (CFA). When it comes to commercializing sorbent, the total cost and efficiency of the adsorbent material are critical. This work used tap water instead of distilled water (DW) to synthesis zeolite from fly ashes at 90°C crystallization temperatures. The discovery lays the door for a cost-effective but easy technique of synthesizing viable zeolitic materials for adsorption applications using waste products like coal fly ash. According to the comprehensive characterization, the support for the use of TP to make zeolites is based on its larger particle size, and lower carbon impurities. The generated zeolite was homogenous and A-type, and applied as an adsorbent to remove traces of heavy metals contaminants. During a 25-minute agitation period, the zeolites produced with TP had a greater adsorption capacity. In principle, the proposed approach permits the synthesis of low-cost, high-efficiency zeolite-based adsorbent materials for environmental remediation without the use of harmful or expensive chemicals
Soil Application of Wheat Straw Vermicompost Enhances Morpho-Physiological Attributes and Antioxidant Defense in Wheat Under Drought Stress
With the provoked environmental constraints under extreme climatic events, a better understanding of plant responses to these environmental stresses helps in obtaining sustainable productivity. Wheat is a significant cereal crop for the burgeoning population; its yield is significantly limited by too little water in the rhizosphere. The ramifications of water deficiency on the wheat crop can be reduced by the application of vermicompost. With the objective to cope with drought stress, a wire-house experiment was established where seedlings of two cultivars, viz., Faisalabad-08 and Galaxy-13 (drought-tolerant and -sensitive cultivar, respectively) were grown in pots and exposed to mild drought (D1, 45% field capacity) and severe drought stress (D2, 30% field capacity). A control with well-watered condition (70% field capacity) was kept for comparison. Various application rates of wheat straw vermicompost (control (VT0), 4 t ha(-1) (VT1), 6 t ha(-1) (VT2), and 8 t ha(-1) (VT3)), were used in soil-filled pots under drought and control treatments. Our data depicted that compared with control, drought treatments recorded a significant reduction in morpho-physiological and biochemical attributes with maximum reduction under severe drought conditions. Nonetheless, it was observed that soil application of vermicompost, particularly at a high rate, ameliorated the negative effects of drought. Under severe drought conditions, a significant and positive influence on morphological and physiological traits was recorded for VT3 treatment, which increased root and shoot length by 27.55 and 27.85%, root and shoot fresh weight by 26.98 and 28.20%, root and shoot dry weight by 40 and 50.05%, and photosynthesis and transpiration rate by 27.65 and 49.25%, respectively, on average of two cultivars. Similarly, VT3 also significantly ameliorated the adverse effect of drought by enhancing the antioxidant enzyme activities as it increased superoxide dismutase activity by 14.28%, peroxidase by 27.28%, and catalase by 50% compared to the control treatment. Among cultivars, Faisalabad-2008 showed comparatively more resistance against drought stress. The findings of this work revealed that drought drastically reduced the growth and productivity of wheat; however, soil-applied vermicompost positively influenced the performance of wheat cultivars.Taif University, Taif, Saudi Arabia [TURSP-2020/94]The current work was funded by the Taif University Researchers Supporting Project Number (TURSP-2020/94), Taif University, Taif, Saudi Arabia
Experimental Study on Seismic Response Characteristics of Soil On Building Models Using 1-D Shake-Table.docx
ABSTRACT. This research investigates the impact of seismic response on the scaled 1:10 multi storey steel frame-model supported by isolated shallow footings placed on sand sample. One dimensional shake-table testing was carried out on four, three and two storeys steel Frame Model subjected to El-Centro 0.46pga Earthquake. Dynamic properties acceleration, displacement, natural frequency of the frame models on isolated footing with changing of storey height were measured. Moreover, it was found that acceleration responses and natural frequencies decreased with an increase in frame model height while displacement responses increased for a given foundation type with increased height. In conclusion, soil, the structure's height, and the materials properties all affect a structures seismic response during an earthquake
Sugarcane Production under Changing Climate: Effects of Environmental Vulnerabilities on Sugarcane Diseases, Insects and Weeds
Sugarcane is an important crop for bioenergy and sugar, contributing to Gross Domestic Product (GDP) of Pakistan. Global warming and increasing greenhouse gas emission result in the increased intensity and frequency of extreme weather events. Temperature stress is a major environmental stress that limits the sugarcane growth, productivity and metabolism worldwide. Numerous biochemical reactions are involved in plant development, and these biochemical reactions are very sensitive to temperature stress. Now a day, temperature stress is a major concern for sugarcane production and approaches for high yield of sugarcane under temperature stress are important agriculture goals. Sugarcane plant adapts a number of acclimation and avoidance mechanism against different environmental stress. Plant survival under different stresses depends on ability to generate and transmit the signal and biochemical and physiological changes. In future, climate change is an important consequence for sugarcane production in the world because of its relative low adaptive capacity, poor forecasting system and high vulnerable to natural hazard. In this review we briefly describe climate change effects on sugarcane, sugar production in several countries especially in Pakistan, future challenges for sugar production under changing climatic scenario and propose strategies for mitigation negative impacts of climate change
Mechanical Behavior of Normal Concrete Reinforced with Kantharo Suter Fiber
Physical characteristics of concrete can be enhanced by addition of different materials in various proportions. Fibrous substances, such as, steel, synthetic, glass, and natural fibers not only increase the structural and tensile strength but also cohesion of concrete by overcoming micro cracks and deficiencies in concrete. In this study, the effect of Kantharo suter fibers (animal hair) on compressive, flexural and split tensile strength, and workability of plain concrete was determined. For that, experiments were conducted on concrete cubes, beams and cylinders by adding different proportions of Kantharo suter fibers from 0.125 to 1.0 percentage by weight of cement. In each proportion of Kantharo suter fibers, three cubes, three cylinders and one beam were casted and cured for 28 days. The acquired results were compared with the plain cement concrete specimens. It was discovered from the results that 0.375 percentages of Kantharo suter fibers in normal concrete was optimum by weight of cement. The strength parameters and slump of concrete showed better results than control mixes even without using any admixture in the specimens. This study could also be enhanced using combinations of different fibers and other admixtures
Controllability of fractional differential evolution equation of order γ∈(1,2) with nonlocal conditions
This paper investigates the existence of positive mild solutions and controllability for fractional differential evolution equations of order with nonlocal conditions in Banach spaces. Our approach is based on Schauder's fixed point theorem, Krasnoselskii's fixed point theorem, and the Arzelà -Ascoli theorem. Finally, we include an example to verify our theoretical results
Drought stress in plants: An overview on implications, tolerance mechanisms and agronomic mitigation strategies
Drought is considered as one of the major limiting factors affecting growth and productivity of crop plants. It severely affects the morphological and physiological activities of the plants and hampers the seed germination, root proliferation, biomass accumulation and final yield of field crops. Drought stress disrupts the biosynthesis of chlorophyll contents, carotene and decreases photosynthesis in plants. It gradually reduces CO2 assimilation rates owing to decrease in stomatal conductance. In addition, drought affects cell membrane stability and disrupts water relations of a plant by reducing water use efficiency. To cope with these situations, plants adopt different mechanisms such as drought tolerance, avoidance and escape. In this review, we discussed about the effects of drought on morphological and physiological characteristics of plants and suggested the different agronomic practices to overcome the deleterious effects of drought stress
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