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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.

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]

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.

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]