Performance of fly ash based polymer gels for water reduction in enhanced oil recovery: Gelation kinetics and dynamic rheological studies

Ahmad Akanbi Adewunmi,Suzylawati Ismail,Abdullah Saad Sultan,Zulkifli Ahmad 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.6

The complexity of well and reservoir conditions demands frequent redesigning of water plugging polymer gels during enhanced oil recovery (EOR). In the present study, we developed coal fly ash (CFA) based gels from polyacrylamide (PAM) polymer and polyethyleneimine (PEI) crosslinker for water control in mature oil fields. The CFA acts as an inorganic additive to fine-tune gelation performance and rheological properties of PAM/PEI gel system. Hence, effects of various CFA (0.5 to 2 wt%), PAM (2 to 8.47 wt%) and PEI (0.3 to 1.04 wt%) concentrations on gelation kinetics and dynamic rheology of pure PAM/PEI gel and PAM/PEI-CFA composite gels were studied at a representative reservoir temperature of 90 oC. Experimental results reveal that gelation time of pure PAM/PEI gel increases with increasing CFA addition. Further observation demonstrates that increasing PAM and PEI concentrations decreases the gelation times of PAM/PEI-CFA composite gels. Gelation time was found to be within 3-120 hours. Understanding the property of reaction order enables better prediction of gelation time. Dynamic rheological data show that viscoelastic moduli (G' and G'') of various PAM/PEI-CFA composite gels improved better as compared to the pure PAM/PEI gel across the strain-sweep and frequency-sweep tests. SEM analysis of selected samples at 72 hours and 720 hours of gelation activity consolidated gelation kinetics and dynamic rheological results. These polymer gels are excellent candidates for sealing water thief zones in oil and gas reservoirs.

Influence of modified perylene-3, 4, 9, 10-tetracarboxylate with alkali metals ions as surfactant on the yield of hydrothermal liquid-phase exfoliated graphene sheets

Ahmad Nurin Jazlina,Mohamed Ruziana,Malek Mohd Firdaus,Sanusi Saedah Munirah,Muhamad Myzatul Azlyin,Ismail Ahmad Syakirin,Mahmood Mohamad Rusop 한국탄소학회 2023 Carbon Letters Vol.33 No.2

Combination of liquid-phase exfoliation and hydrothermal method has progressed in recent years mainly on production of 2D materials. In this study, graphene was successfully synthesized via combinatorial of liquid-phase exfoliation and hydrothermal method with the aid of various conductive surfactants perylene-3, 4, 9, 10-tetracarboxylate (PTCA), lithium perylene-3, 4, 9, 10-tetracarboxylate (LiPTCA) and sodium perylene-3, 4, 9, 10-tetracarboxylate (NaPTCA). The effect of the lithium (Li+) and sodium (Na+) cations toward the efficiency of the graphene exfoliation process and its electrical properties was thoroughly investigated. Based on the characterization techniques, it is revealed that NaPTCA is the ideal conductive surfactant to exfoliate graphene sheets. X-ray diffraction spectra verified that the Na+ cation certainly can enhance the exfoliation process by expanding the interlayer spacing. The lateral size of the graphene sheets with Na-PTCA surfactant was the smallest (4.17 µm) as observed from SEM micrograph. The maximum concentration of the graphene yield was achieved up to 0.151 mgmL−1 in NaPTCA surfactant alongside with excellent electrical conductivity of 746.27 Sm−1 and relevant specific capacitance of 129 Fg−1.

Extended Technology Acceptance Model for Enhanced Distribution Strategies to Online Learning: Application of Phantom Approach

Izzat ISMAIL,Asyraf AFTHANORHAN,Noor Aina Amirah MOHAMAD NOOR,Nurul Aisyah Awanis A RAHIM,Sheikh Ahmad Faiz Sheikh Ahmad TAJUDDIN,Muhammad Takiyuddin Abdul GHANI 한국유통과학회 2024 유통과학연구 Vol.22 No.4

Purpose: This study is aimed to introduce the application of phantom approach with structural equation modelling method for online learning. By integrating these innovative methodologies, the research seeks to advance the understanding of how the phantom approach can effectively complement and augment structural equation modeling techniques. Research design, data and methodology: A theoretical framework of Technology Acceptance Model (TAM) was modified and updated. A questionnaire was developed and used to extract information from 189 instructors who used online learning as their primary medium. The Covariance Based Structural Equation Modelling (CBSEM) was applied to test the direct effects and the phantom approach is used to handle the 2 mediators in the model. Results: social influence, perceived usefulness, and perceived ease of use exerted discernible impacts on instructors' intentions to engage in online learning. These findings illuminate the intricate dynamics influencing instructor behavior within the realm of online education, underscoring the significance of various factors in shaping their intentions. Conclusions: In additions, the perceived usefulness and perceived ease of use had mediated the effect of social influence and instructor intention using phantom approach. Therefore, one can have concluded that this modified model was also confirmed, thereby reinforcing distribution strategies to online learning and overall education presence.

Pharmacognostic Profile of Trigonella Seed and Its Hypoglycaemic Activity

Zhari Ismail,Norhayati Ismail,Mariam Ahmad 한국생약학회 1995 Natural Product Sciences Vol.1 No.1

Pharmacognostic study was carried out on the seeds of Trigonella foenumgraecum L. (fenugreek) in order to establish its pharmacognostic characteristics. In view of its renewed interest as a dietary supplement among the local inhabitants afflicted with diabetes, its hypoglycaemic activity in normal as well as diabetic rats was also investigated. Oral glucose tolerance test showed that a suspension of the powdered trigonella seed inhibited the increase in blood glucose levels in normal rats that had been treated with an oral glucose load prior to the test. A reduction in the blood glucose levels was also observed when a suspension of the powdered seed was given by gastric intubation to the streptozotocin-induced diabetic rats. These findings suggested that trigonella seeds possessed some hypoglycaemic activities that might be useful to the diabetics.

Sine based Bacterial Foraging Algorithm for a Dynamic Modelling of a Twin Rotor System

Shuhairie Mohammad,Mohd Falfazli Mat Jusof,Nurul Amira Mhd Rizal,Ahmad Azwan Abd Razak,Ahmad Nor Kasruddin Nasir,Raja Mohd Taufika Raja Ismail,Mohd Ashraf Ahmad 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

This paper introduces a sine-based position update strategy into Bacterial Foraging Algorithm (BFA). In solving many optimization problems, BFA produces an acceptable accurate solution but it presents a slow convergence speed towards the global solution. On the other hand, a sine-based position update strategy from the Sine Cosine Algorithm (SCA) utilizes an elitism in its position update equation. The elitism strategy contains a promising solution that guiding search agents toward global optima with relatively a faster speed. In this proposed technique, the sine-based position update strategy is incorporated prior to the reproduction phase of the BFA. With the consideration of the advantages of the elitism, it helps the BFA to converge faster and hence acquires better accuracy of the final solution. The proposed algorithm is tested on several CEC2014 benchmark functions that have various fitness landscapes and features. For solving a real world problem, it is applied to optimize a dynamic model of a Twin Rotor System. Result of the test shows that the proposed algorithm significantly outperforms the original BFA for both convergence speed and accuracy performances. On the other hand, result of the modelling shows that the proposed algorithm acquires the dynamic model for the Twin Rotor System with a significant smaller error.

Measurement and Structural Modelling on Factors of Islamic Payment Gateway System Among Millennial Generation in Malaysia

Ahmad Mujahid Mat Rasid,Mohammed Hariri Bakri,Geraldine d/o John Philip De Mello,Albert Feisal Muhd Feisal Ismail,Mohamad Idham Md Razak People&Global Business Association 2023 Global Business and Finance Review Vol.28 No.6

Purpose: This study aims to develop a conceptual model and validate the model using a unified theory of acceptance and use of technology to determine the Determinants of Intention to Use the Islamic Payment Gateway System among the Millennial Generation in Malaysia via a Structural Model. Based on past research, the UTAUT hypothesises four variable constructs: performance expectancy, effort expectancy, social Influence, and facilitating factors. These characteristics are predictive of behavioural intent. In terms of the study, the author added a religiosity variable instead of the four recommended moderators. Design/methodology/approach: A total of 303 field tests have been obtained from Malaysian millennial citizens using Islamic Fintech. Before the data is analysed into exploratory factor analysis, preliminary analysis such as normality and multicollinearity test has been conducted. Findings: All constructs, which are performance expectancy, effort expectancy, social Influence, facilitating condition, and behavioural intention with religiosity as the moderating, have no factor reduction, but all constructs identified two components under exploratory factor analysis. Moreover, all construct KMO tests more than 0.50. All constructs met unidimensionality, validity, reliability, and model fitness in CFA. All the requirements for model fit in this study have been achieved. Research limitations/implications: This study has significant consequences, particularly for the existing payment gateway system, which is already entering every area of human lifestyle with the millennial generation being targeted as the native user. Originality/value: This study fills the apparent gap in the existing payment gateway system literature by assessing religiosity as moderating through exploratory factor analysis.

Economic Analysis of Thorium Extraction from Monazite

Ahmad Hayaton Jamely Mohd Salehuddin,Aznan Fazli Ismail,Che Nor Aniza Che Zainul Bahri,Eli Syafiqah Aziman 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.2

Thorium (232Th) is four times more abundant than uranium in nature and has become a new importantsource of energy in the future. This is due to the ability of thorium to undergo the bombardment ofneutron to produce uranium-233 (233U). The aim of this study is to investigate the production cost ofthorium oxide (ThO2) resulted from the thorium extraction process. Four main parameters were studiedwhich include raw material and chemical cost, total capital investment, direct cost and indirect cost. These parameters were justified to obtain the final production cost for the thorium extraction process. The result showed that the raw material costs were $63,126.00 e$104,120.77 (0.5 ton), $126,252.00 e$178,241.53 (1.0 ton), and $1,262,520.00 e$1,782,415.33 (10.0 tons). The total installed equipment andtotal cost investment were estimated to be approximately $11,542,984.10 and $13,274,431.715 respectively. Hence, the total costs for producing 1 kg ThO2were $6829.79e $6911.78, $3540.95 e $3592.94,and $501.18 e $553.17 for 0.5, 1.0, and 10.0 tons respectively. The result concluded that with higher massproduction, the cost of 1 kg ThO2 would be reduced which in this scenario, the lowest production costwas $501.18 kg 1e $553.17 kg 1 for 10.0 tons of ThO2 production.

Measurement and Structural Modelling on Factors of Islamic Payment Gateway System Among Millennial Generation in Malaysia

Ahmad Mujahid Mat Rasid,Mohammed Hariri Bakri,Geraldine d/o John Philip De Mello,Albert Feisal Muhd Feisal Ismail,Mohamad Idham Md Razak 사람과세계경영학회 2023 Global Business and Finance Review Vol.28 No.-

Purpose: This study aims to develop a conceptual model and validate the model using a unified theory of acceptance and use of technology to determine the Determinants of Intention to Use the Islamic Payment Gateway System among the Millennial Generation in Malaysia via a Structural Model. Based on past research, the UTAUT hypothesises four variable constructs: performance expectancy, effort expectancy, social Influence, and facilitating factors. These characteristics are predictive of behavioural intent. In terms of the study, the author added a religiosity variable instead of the four recommended moderators. Design/methodology/approach: A total of 303 field tests have been obtained from Malaysian millennial citizens using Islamic Fintech. Before the data is analysed into exploratory factor analysis, preliminary analysis such as normality and multicollinearity test has been conducted. Findings: All constructs, which are performance expectancy, effort expectancy, social Influence, facilitating condition, and behavioural intention with religiosity as the moderating, have no factor reduction, but all constructs identified two components under exploratory factor analysis. Moreover, all construct KMO tests more than 0.50. All constructs met unidimensionality, validity, reliability, and model fitness in CFA. All the requirements for model fit in this study have been achieved. Research limitations/implications: This study has significant consequences, particularly for the existing payment gateway system, which is already entering every area of human lifestyle with the millennial generation being targeted as the native user. Originality/value: This study fills the apparent gap in the existing payment gateway system literature by assessing religiosity as moderating through exploratory factor analysis.

New Bone Formation in Tuberculous-Infected Vertebral Body Defect after Administration of Bone Marrow Stromal Cells in Rabbit Model

Ahmad Jabir Rahyussalim,Tri Kurniawati,Nurjati Chairani Siregar,Agus Syahrurachman,Ismail Hadisubroto Dilogo,Diah Iskandriati,Arni Diana Fitri 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.1

Study Design: Preliminary experimental study using a rabbit spondylitis model. Purpose: To observe the ossification in a micro-environment containing live Mycobacterium tuberculosis transplanted with bone marrow stromal cells (BMSCs) in rabbits. Overview of Literature: BMSCs differentiate to osteoblasts and then osteocytes during ossification. Mycobacterium tuberculosis does not affect BMSC growth in vitro . Methods: Six rabbits were divided into two groups of three rabbits. One group was positive for spondylitis tuberculosis by culture, polymerase chain reaction (PCR), and histopathologically. The other group was positive by PCR and histopathologically. Both groups were treated using BMSC transplantation and anti-tuberculosis drugs. After 6 weeks, ossification was evaluated by enumerating the number of osteoblasts, osteocytes, and lesion level of calcium. Results: Mean number of osteoblasts was 207.00±31.00 in the first group and 220.33±73.46 in the second group. Mean number of intra-lesions osteocytes was in the first and second group was 18.33±30.04 and 31.00±26.87, respectively. Mean calcium level in the first group and second group was 2.94%±0.89% and 2.51%±0.13%, respectively. Total ossification score in the first and second group was 31.00 and 25.67, respectively. Conclusions: Mycobacterium tuberculosis provides support for new bone formation by stimulating intra-lesion calcium metabolism. The microscopic environment containing live Mycobacterium tuberculosis enhances ossification.

Response of Lipid Profile to Laser Acupuncture along with Diet and Pilates Exercise in Obese Women with Systemic Lupus Erythematosus: a Randomized Controlled Trial

Ismail Ali Mohamed Ali,Saad Ahmad Elsayed,Abd-Elrahman Noha Ahmed Fouad,Elfahl Ahmed Mohamed Abdelhalim 사단법인약침학회 2023 Journal of Acupuncture & Meridian Studies Vol.16 No.4

Background: Obesity-induced dyslipidemia is one of the main factors contributing to morbidity and mortality associated with metabolic syndrome, atherosclerosis, and coronary artery disease among patients with systemic lupus erythematosus (SLE). Objectives: This research aimed to assess the effect of adding laser acupuncture therapy (LAT) to a Pilates exercise program (PEP) and low-calorie diet protocol (LCDP) on blood lipids among 60 obese women with SLE. Methods: Study participants were women aged between 23 and 49 years, randomly assigned to one of two groups, A or B, each comprising 30 women. In addition to adherence to the LCDP, both groups were supervised five times weekly during 50-minute PEP sessions. Group A also received LAT three times weekly, with each session lasting 2 minutes on selected acupoints. After the 12-week intervention, plasma total cholesterol, high-density lipoprotein, triglycerides, and low-density lipoprotein were assessed. Results: Both groups demonstrated significant improvement in the aforementioned lipids after the 12-week intervention. A comparison between the post-intervention values of the lipids in the groups revealed a significant improvement favoring group A (the group that received LAT). Conclusion: Adding a 12-week LAT regimen to PEP and LCDP significantly improved lipid profiles among 60 obese women with SLE.