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The irradiation variations caused by cloud changes can cause rapid power fluctuations in large photovoltaic (PV) plants. The increased PV power share of the grid adversely affects the quality of power and the reliability of the power supply. Energy storage systems (ESSs)are often used to mitigate power fluctuations in the grid through various control algorithms. These algorithms create an ESS power reference that opposes the variations of the PV and reduces them to an acceptable value. Despite their everyday use, there have been few performance comparisons among the various methods, especially battery status, and the battery can operate in several systems with various smoothing methods. The paper aims to analyze the ramp-rate and step-rate control methods for smoothing solar PV fluctuations based on the irradiation profiles in a DC microgrid (MG) environment. The battery in the system operates as a continuous energy application, and a supercapacitor (SC) is used to remove transients in the battery system. The combined battery-SC coordinated system improves the performance of the DC microgrid system. The battery cycle analysis and depth are conducted using the well-established Coulomb counting technique. MATLAB/Simulink validates the simulation results, and the OP-5700 HIL test bench conducts real-time results.

Dishonest academic behavior (DAB) by students in Chinese higher education institutions has become a significant concern. However, the related study of academic dishonesty in mainland China is very limited. This study fills this gap by examining the theory of planned behavior and its three extended versions, validating the effectiveness of predicting DAB among Chinese undergraduates, and testing 11 developed hypotheses. This study uses a quantitative research design, and responses are collected online from 525 undergraduate students from five disciplines in the second to fourth year at a public university in China. The results reveal the proposed models have good fitting indices and support 10 hypothetical relationships. These relationships demonstrate that attitudes, norms and control beliefs significantly impact intentions and justifications. Meanwhile, behavioral control, intentions, and justifications significantly influence DAB. Notably, this study found a direct and significant effect of MO on justifications. Therein, Model four best explains the variance in DAB and provides practical support for the expanded TPB models’ application in China.

The steady rise in utility grid penetration of single phase solar photovoltaic system has contributed to the mandatory requirement of Low Voltage Ridethrough (LVRT) capability. LVRT capability provides stable grid integration during transient conditions. A seamless LVRT capability operation in a single phase photovoltaic system using peak value based fault detection and Orthogonal Signal Generation (OSG) based voltage sag detection is conducted. In this paper, two controllers are employed for two different operations. The PQ theory controller is used for power control operation and Proportional–Resonant (PR) with Harmonic Compensation (HC) controller is used for current control operation in LVRT. MATLAB/Simulink verifies the LVRT operation mode as per the grid code requirements to ride through voltage sag during fault condition. It is observed that the system is in operation during transient conditions and provides reactive support to ride through the fault.

This paper consolidates the findings of two studies conducted in Brunei Darussalam on the incidences of bullying among Primary and Secondary school pupils. Students from both Primary and Secondary schools responded to a questionnaire on the incidence of bullying in their school. Results from the studies show that the frequency of the incident of bullying peaked at around secondary one and showed a decline in the upper forms. While the ranking of the types of bullying experienced by students at the different levels of schooling were similar, differences were noted in the ranking of the types of bullying experienced by boys and girls particularly in the primary years. Psychological bullying was more common among girls whereas bullying of a physical nature was more common among boys. The classroom was the place where students‟ experienced most bullying and a close friend and parent were the individuals to whom most students would report the incidence of bullying. Some implications for classroom practice and further research are discussed.

In this paper presents a comparative analysis of two control method applied to a single phase Shunt Active Power Filter (SAPF). It is about Model Predictive Control (MPC) based Direct Current Control (DCC) and Indirect Current Control (IDCC) strategy. The performances of two current control strategies were verified through a simulation with MATLABSimulink Software. Simulation results confirmed that compared to the DCC strategy, the IDCC strategy using MPC becomes simpler and need less hardware components.

Green-synthesized silver and copper nanoparticles (NPs), along with their composites, exhibit various biological activities. Ocimum sanctum (Holy basil), traditionally used as medicine in South Asia, treats respiratory disorders, digestive issues, skin diseases and inflammatory conditions. Modern scientific studies support these bioactivities; however, no studies have investigated their bioactivity in combination with NPs. In this study, silver and copper NPs were synthesized using AgNO3 and CuSO4·5H2O solutions, respectively, with Ocimum sanctum leaf extract, and their antibacterial, antioxidant and anticancer properties were examined. Spectroscopic analyses, including Fourier transform infra-red (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XRD), elucidated the physicochemical characteristics of the green-synthesized nanoparticles (Os-AgNPs and Os-CuNPs), revealing sizes of 11.7 and 13.1 nm, respectively. The Os-AgNPs:Os-CuNPs nano-composite with a 1:2 ratio exhibited a zone of inhibition ranging from 8 to 12 mm against tested bacterial pathogens. Additionally, the NPs and their composites demonstrated potent antioxidant activity, with notable 2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity observed in composites with ratios of 2:1 and 1:2. Furthermore, they displayed potential anticancer activity against human leukaemia (Jurkat) cancer cells. Although no distinct difference in anticancer property was observed among the NPs and their composites, our study highlights their well-defined nanostructure and significant biological activity, suggesting their potential as therapeutic agents in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

This paper demonstrates an enhancement of power quality for a photovoltaic (PV) system connected to the grid with a hybrid energy storage system (HESS). The proposed system utilizes a ramp-rate control (RRC) strategy to limit severe fluctuations in the PV power output. Battery storage is integrated to store surplus energy generated by the PV system and is used for continuous power application. A high-power density device, known as a supercapacitor (SC), is employed to mitigate transient fluctuations in the battery. The proposed system facilitates smooth PV power generation, stabilizes the DC bus voltage (VDC), and eliminates source current harmonics induced by non-linear loads. The Shunt Active Power Filter (SAPF) discussed in this paper serves two primary purposes. Firstly, it acts as a reactive power buffer, smoothing out fluctuations and reducing current harmonic distortions. Secondly, it enables active power injection into the grid, utilizing a specific renewable solar PV source. The efficiency of the modeled compensation system is demonstrated by the sinusoidal shape of the current and the compensation of reactive power (RPC). The targeted system showcases the effectiveness of the current setup by exhibiting low total harmonic distortion (THD). The multifunctional features of the proposed system were implemented using the MATLAB/Simulink software, and the results were validated using an OP5700 Hardware-in-the-Loop (HIL) test bench. This integration of distributed power generation capabilities not only enhances the overall power quality but also improves the efficient utilization of renewable energy resources (RESs). [ABSTRACT FROM AUTHOR]

Biocompatible cholinium-based ionic liquids (ILs) are used extensively in the pharmaceutical and biomedical industries. To enhance structural stability and solubility of drugs, as well as their controlled delivery, IL-based active pharmaceutical ingredients (API) are used widely. In this study, we selected two different sets of biodegradable ILs which also have a direct influence on the structure and stability of insulin. Moreover, we used DFT-based electronic structure calculations with molecular dynamics (MD) simulations to study the effect of a mixture of two different anions in the IL medium and the role of water molecules on the stability of insulin. Microhydration and molecular-level DFT calculations suggest that ILs based on choline geranate [Cho][Ger] and choline taurine [Cho][Tau] differ in their hydration patterns, and thus the stability of the clusters varies significantly. This finding is important for exploring the role of water molecules within these mixtures (i.e., on the interactions between [Ger] and [Tau]). From our calculations it is found that the [Cho][Ger] IL stabilizes the insulin dimer structure strongly through water-mediated H-bonding interactions, whereas the [Cho][Ger][Tau] ternary complex destabilizes insulin. This indicates that IL mixtures over a wide range of concentrations and water molecules at the interface may influence the structural stability and enable suitable combinations of oral formulations to be predicted for drug-delivery applications. From the MD simulations, we conclude that [Cho][Ger] stabilizes the insulin dimer. Our combined DFT and MD simulations will provide valuable information for experimentalists to design and develop novel oral insulin formulations. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) have attracted significant attention due to their unique electronic, optical, physical, and chemical properties. As nanoscale fragments of graphene rich in electrons, GQDs offer enhanced capabilities that elevate their potential across a wide range of applications. This review paper delves into the synthesis, characterization, and applications of functionalized graphene quantum dots (FGQDs), which exhibit exceptional photoelectronic properties resulting from quantum confinement and edge effects. These features position FGQDs as promising materials for optoelectronic technologies. The review also highlights various functionalization strategies, providing valuable insights for researchers seeking to optimize GQDs for specific applications. By understanding the correct functionalization techniques, researchers can tailor the properties of FGQDs to enhance their performance in a range of applications. This article offers an in-depth discussion of synthetic approaches for producing FGQDs with diverse chemical groups and functionalities, alongside a thorough overview of characterization techniques, ranging from morphological and crystallographic analysis to componential and absorption spectroscopy. Furthermore, the review explores the growing potential of FGQDs in biomedical applications, including biosensing, bioimaging, drug delivery, and therapeutics. It underscores the advances in research and development that are crucial for unlocking the full biomedical potential of FGQDs, while also addressing the challenges that remain to be tackled in the future. As the field continues to evolve, the insights presented in this review provide a solid foundation for future breakthroughs in the synthesis and application of FGQDs.

Air-oil separator is used to recover oil from the air leaving the compressor. The air-oil separator design is based on the minimum diameter of capturing oil droplet and the separation efficiency of the separator. The available air-oil separators are Cyclone, Labyrinth, wire and oil filter. In this work cyclone separator is proposed due to its higher separation efficiency for wide range of droplet size. The proposed model C1 to C6 is analysed using CFD tool and maximum separation efficiency is obtained for C4 model and minimum residence time & static pressure is obtained for C3 model. It is concluded that C3 model is finalized model due to least residence time and back pressure with acceptable separation efficiency. [ABSTRACT FROM AUTHOR]

Dishonest academic behavior (DAB) by students in Chinese higher education institutions has become a significant concern. However, the related study of academic dishonesty in mainland China is very limited. This study fills this gap by examining the theory of planned behavior and its three extended versions, validating the effectiveness of predicting DAB among Chinese undergraduates, and testing 11 developed hypotheses. This study uses a quantitative research design, and responses are collected online from 525 undergraduate students from five disciplines in the second to fourth year at a public university in China. The results reveal the proposed models have good fitting indices and support 10 hypothetical relationships. These relationships demonstrate that attitudes, norms and control beliefs significantly impact intentions and justifications. Meanwhile, behavioral control, intentions, and justifications significantly influence DAB. Notably, this study found a direct and significant effect of MO on justifications. Therein, Model four best explains the variance in DAB and provides practical support for the expanded TPB models' application in China. [ABSTRACT FROM AUTHOR]

Background: Green synthesized nanoparticles (NPs) have gained increasing popularity in recent times due to their broad spectrum of antimicrobial properties. This study aimed to develop a phytofabrication approach for producing cuprous (Cu2O) and cupric oxide (CuO) NPs using a simple, non-hazardous process and to examine their antimicrobial properties. Methods: The synthesis employed Bidens pilosa plant extract as a natural reducing and stabilizing agent, alongside copper chloride dihydrate as the precursor. The biosynthesized NPs were characterized through various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Results: XRD analysis confirmed that the synthesized CuO and Cu2O NPs exhibited a high degree of crystallinity, with crystal structures corresponding to monoclinic and face-centered cubic systems. SEM images revealed that the NPs displayed distinct spherical and sponge-like morphologies. EDS analysis further validated the purity of the synthesized CuO NPs. The antimicrobial activity of the CuO and Cu2O NPs was tested against various pathogenic bacterial strains, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus, with the minimum inhibitory concentration (MIC) used to gauge their effectiveness. Conclusions: The results showed that the phytosynthesized NPs had promising antibacterial properties, particularly the Cu2O NPs, which, with a larger crystal size of 68.19 nm, demonstrated significant inhibitory effects across all tested bacterial species. These findings suggest the potential of CuO and Cu2O NPs as effective antimicrobial agents produced via green synthesis.

Abstract In modern era, deficiency of Vitamin D3 is predominantly due to limited exposure to sunlight and UV radiation resulting from indoor lifestyles. Several studies have revealed that vitamin D deficiency can lead to chronic vascular inflammation, diabetes mellitus, hypertension, congestive left ventricular hypertrophy, and heart failure. This study introduces a green synthesis of novel bimetallic nanoporous composite, CuO/Ag using lemon extract. The synthesized nanoporous material, CuO/Ag@lemon extract was characterized using several analytical techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The CuO/Ag@lemon extract nanoparticles were immobilized on glassy carbon electrode (GCE) to prepare modified CuO/Ag@lemon extract–GCE interface. The electrocatalytic and electrochemical properties investigation was carried out on the modified electrode. using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and amperometry for detecting of Vitamin D3. The DPV method displayed a linear response range of 0.02–22.5 µM with a detection limit of 2.62 nM, while the amperometric method showed a broader linear range of 0.25–23.25 µM with a detection limit of 2.70 nM with 82% modified electrode stability. The designed electrode exhibited a positive response to the inclusion of Vitamin D3 with electro-oxidation, reaching steady-state within 3.4 s, with 87% reproducibility within a day. The proposed method offers a rapid and sensitive platform for detection of Vitamin D3 with minimal interference from other molecules. The early diagnosis of Vitamin D3 deficiency using modified electrodes allows for early treatment, thereby preventing severe health complications.

An efficient sensing surface is fabricated through incorporating ruthenium on electropolymerized poly-(4-aminodiphenylamine)(Padpa) film by potentiodynamic cycling of 4-aminodiphenylamine (4-adpa) in an acidic medium. The mechanism of electropolymerization comprises the conversion of protonated monomer to di-imine species and generates positively charged radical-intermediate via dimerization step. The surface morphology of deposited film on electrode surface is studied using SEM and XPS techniques. The electrocatalytic appraisal of constructed (Ru/Padpa/GCE) sensing interface is examined towards the electro-oxidation of guaifenesin (GUA) by differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronoamperometric (CA) methods. The Ru/Padpa/GCE sensing interface displayed a linear response of GUA from 1.5 to 45 µg/mL with the limit of detection (LOD) of 48.8 ng/mL (S/N = 3). The obtained higher activity of Ru/Padpa/GCE is mainly attributed to its larger active surface area, faster electron transfer kinetics, and higher catalytic sites from the interface. The Ru/Padpa/GCE sensing interface is further applied for the determination of GUA in pharmaceutical (cough syrup, and human urine) samples with a recovery of 97.1–101.0 %. The diffusion coefficient of GUA (1.51 × 10-6 cm2/s) is also obtained via theoretical electrochemical method, which ensures that Ru/Padpa/GCE sensing interface can be considered as a potential candidate for clinical diagnostic analysis.