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991.
992.
Saleh Alhazbi;Afnan Al-ali;Aliya Tabassum;Abdulla Al-Ali;Ahmed Al-Emadi;Tamer Khattab;Mahmood A. Hasan; 《Journal of Computer Assisted Learning》2024,40(4):1658-1674
Measuring students' self-regulation skills is essential to understand how they approach their learning tasks in order to identify areas where they might need additional support. Traditionally, self-report questionnaires and think aloud protocols have been used to measure self-regulated learning skills (SRL). However, these methods are based on students' interpretation, so they are prone to potential inaccuracy. Recently, there has been a growing interest in utilizing learning analytics (LA) to capture students' self-regulated learning (SRL) by extracting indicators from their online trace data. 相似文献
993.
M. Amin F. Zarandi Krishna M. Pillai Abul Borkot Md Rafiqul Hasan 《American Institute of Chemical Engineers》2022,68(11):e17807
To validate the experimental results of Part-1, we conducted a two-phase flow simulation of imbibition of a wetting liquid through 2D microstructures made of ellipses of varying aspect ratios. The flow simulation in the particulate microstructures, characterized by low (ellipse) aspect ratio, produced somewhat even micro-fronts, thus replicating the sharp fronts at the visual (macroscopic) scale observed in Part-1. Whereas simulations in the fibrous microstructures produced highly uneven micro-fronts, suggesting the formation of semi-sharp or diffuse visual fronts. Increasing the porosity from 50% to 70% resulted in solid-phase clustering and led to further increase in the unevenness of micro-fronts, pointing to purely diffuse visual fronts. The evolution of the saturation plots along the flow direction, obtained from area-averaging of fluid-distribution plots, pointed to diffusing of sharp fronts with time. The predictions matched our previous experimental and numerical observations, that is, the particulate media create sharp fronts while the fibrous media create semi-sharp/diffuse fronts. 相似文献
994.
Dr. Md. Sailful Islam Dr. Cyrille C. Thinnes Dr. James P. Holt-Martyn Dr. Rasheduzzaman Chowdhury Dr. Michael A. McDonough Prof. Christopher J. Schofield 《ChemMedChem》2022,17(1):e202100398
Studies on the inhibition of the human 2-oxoglutarate dependent oxygenase JMJD6, which is a cancer target, by 2-oxoglutarate mimics / competitors, including human drugs, drug candidates, and metabolites relevant to cancer are described. JMJD6 assays employed NMR to monitor inhibitor binding and use of mass spectrometry to monitor JMJD6-catalysed lysine hydroxylation. Notably, some clinically applied prolyl hydroxylase inhibitors also inhibit JMJD6. The results will help enable the development of inhibitors selective for human oxygenases, including JMJD6. 相似文献
995.
ABSTRACTMemory-resistor (Memristor) has drawn considerable attention of the researchers in the last decade due to its remarkable properties. After the first concept of memristor, proposed by Leon Chua in 1971, almost no research work was conducted in this field for a long time. However, since the revolutionary discovery of the physical structure of memristor and its model of the HP lab in 2008, a tremendous amount of research work has been going on. Researchers are focusing on improving the models for the analysis of the memristor. Different researchers have come up with their model to improve the existing ones. These models can be linear, nonlinear or exponential. To overcome the boundary problem, many window functions have been proposed. Different models have their explanations of voltage-current relationship and state variable derivatives. This paper presents a detailed review and a comparative study of the existing memristor models based on their I-V characteristic curve. Original experimental I–V curve from the HP lab has been used as the reference for comparison. 相似文献
996.
Md Ashiqur Rahman Laskar Wenqin Luo Nabin Ghimire Ashraful Haider Chowdhury Behzad Bahrami Ashim Gurung Khan Mamun Reza Rajesh Pathak Raja Sekhar Bobba Buddhi Sagar Lamsal Ke Chen Md Tawabur Rahman Sheikh Ifatur Rahman Khalid Emshadi Tingting Xu Mao Liang Wen‐Hua Zhang Qiquan Qiao 《Advanced functional materials》2020,30(22)
In recent years, hybrid perovskite solar cells (HPSCs) have received considerable research attention due to their impressive photovoltaic performance and low‐temperature solution processing capability. However, there remain challenges related to defect passivation and enhancing the charge carrier dynamics of the perovskites, to further increase the power conversion efficiency of HPSCs. In this work, the use of a novel material, phenylhydrazinium iodide (PHAI), as an additive in MAPbI3 perovskite for defect minimization and enhancement of the charge carrier dynamics of inverted HPSCs is reported. Incorporation of the PHAI in perovskite precursor solution facilitates controlled crystallization, higher carrier lifetime, as well as less recombination. In addition, PHAI additive treated HPSCs exhibit lower density of filled trap states (1010 cm?2) in perovskite grain boundaries, higher charge carrier mobility (≈11 × 10?4 cm2 V?1 s), and enhanced power conversion efficiency (≈18%) that corresponds to a ≈20% improvement in comparison to the pristine devices. 相似文献
997.
Md Shariful Islam Abu Naser Zafar Ullah Shristi Mainali Md. Akhter Imam Md Imran Hasan 《Food Science & Nutrition》2020,8(9):4685-4695
Stunting is a major problem in Bangladesh, with a prevalence of 31% in 2017. The prevalence of stunting in children aged under two has reduced by only 6% since 2004. After children reach 2 years of age, the consequences of stunting become almost irreversible. This paper seeks to examine and analyze the determinants associated with stunting during the first 1,000 days of life in Bangladesh to assist in developing evidence‐based interventions in Bangladesh. A literature review was conducted comprehensively on all relevant peer‐reviewed and gray literature of studies conducted in Bangladesh. The existing literature was searched and examined using the World Health Organization (WHO) conceptual framework for stunting. Evidence indicates that low maternal weight, lack of maternal education, severe food insecurity, lack of access to suitable nutrition, nonexclusive breastfeeding, pathogen‐specific diarrhea, and low weight and height at birth are associated with early childhood stunting in Bangladesh. The relation of the quality of drinking water with stunting is not clear in Bangladesh. Literature about the association between stunting and determinants such as the political economy, education systems, and agriculture and food systems is not found. This synthesis shows that the factors of stunting are multifaceted. As such, a multi‐sectoral approach is essential in Bangladesh, employing evidence‐based interventions to address the determinants that contribute to the risk of stunting to achieve the global nutrition target by 2025. 相似文献
998.
Hasan M. Nuwayer Gurpinder Singh Dhaliwal Golam M. Newaz 《Journal of Adhesion Science and Technology》2020,34(12):1348-1370
AbstractTime-dependent behavior is characteristic of adhesively bonded structureswhen put under constant load (creep). In this study, adhesively bonded beam specimens prepared by adhesively bonding two unidirectional carbon fiber laminated beams were subjected to accelerated three-point bending creep tests. A three-point bending test was selected because of its simplicity and the fact that bending stresses tend to develop in structures under load even if not subjected to direct flexural load. The aim of this study is to predict the long-term behavior and to investigate the long-term creep response of the adhesively bonded composite system. The long-term creep behavior was predicted by time–temperature superposition principle (TTSP) and construction of the master curve at a reference temperature. 相似文献
999.
S.M. Rezaul Hasan 《International Journal of Circuit Theory and Applications》2020,48(7):1194-1200
This paper presents an elegant technique for the mid-band analysis of a “nonideal” drain-loaded source-follower. The analysis of the drain-loaded source-follower is then applied to the superposition-based mismatch differential-gain analysis of a differential amplifier. This novel technique provides a more comprehensive mismatch gain analysis of the differential amplifier compared to that available in text books and other published sources. The presented analysis of a “nonideal” drain-loaded source-follower has not been reported before in open literature in any form. This new method renders the need for the well-known and commonly employed “voltage-divider” form of the source-follower analysis unnecessary. A more accurate differential-amplifier mismatch gain expression is attained using a much simpler source-follower mid-band analysis technique. 相似文献
1000.
Arpita Paul Chowdhury Baban H. Shambharkar 《International Journal of Applied Ceramic Technology》2020,17(3):1467-1478
We have synthesized novel BiOCl-CoWO4 heterostructured nanocomposites through chemical precipitation route with different amount of CoWO4 using KCl as Cl source at a temperature of 100°C, 4 hours. X-ray diffraction, transmission electron microscopy, UV-visible NIR spectroscopy, photoluminescence spectroscopy, N2 adsorption-desorption isotherms, and electrochemical impedance spectroscopy were performed to gain the crystal structure, morphology, optical properties, surface area, and charge separation of the prepared photocatalysts. BiOCl-CoWO4 composites demonstrated the diffraction peaks of both monoclinic CoWO4 nanoparticles and tetragonal BiOCl indicating the formation of the nanocomposite. TEM observations have shown that CoWO4 nanoparticles were deposited on the BiOCl surface. Photoluminescence, fluorescence lifetime study, and Electrochemical impedance spectroscopy responses of materials indicated a good separation efficiency of charge carriers in BiOCl-CoWO4-1. The photodegradation efficiency of the prepared materials was assessed by the decomposition of rhodamine B (RhB) dye solution under sunlight irradiation. Among the synthesized materials, the BiOCl-CoWO4-1 composite photocatalyst exhibited maximum photocatalytic activity. Thus the resulting heterostructure favored the efficient charge and energy transfer between BiOCl and CoWO4 nanoparticles across the interface. The investigations from the radical scavenger tests showed that photogenerated h+, O2 ∙ −, and •OH radicals were involved in the photodegradation of RhB. 相似文献