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In this work we are presenting the hydrothermal method to synthesize NiTiO3 perovskite nanoparticles (NPs). The effect of variation in reaction temperature on the structural, optical, electrical and gas sensing properties of NiTiO3 nanoparticles was investigated. The nanoparticles synthesized at different reaction temperatures were characterized by various characterization methods like XRD, FTIR, UV–Visible Spectroscopy, FESEM, TEM, HRTEM and SAED. The results of UV–Visible analysis revealed that band gap of NiTiO3 decreased from 2.90 to 2.56 eV on increase in reaction temperature from 140 to 200 °C. The XRD analysis showed that crystallite size decreased in the range of 21 to 12 nm on increase in reaction temperature. The various parameters of the material like dislocation density, microstrain and crystallinity were also calculated from XRD data. The average particle size was estimated by FESEM analysis and found to be decreased on increase in reaction temperature. FTIR analysis confirmed the formation of NiTiO3. Study of electrical properties proved the semiconducting behaviour of NiTiO3. The detail analysis of NiTiO3 sensor characteristics in terms of sensitivity, selectivity, response and recovery time was carried out. The study of gas sensing performance of NiTiO3 revealed that NiTiO3 synthesized at 140 °C showed maximum sensitivity to CO2 gas at room temperature, whereas NiTiO3 synthesized at 200 °C showed maximum sensitivity to H2S gas at 250 °C. [ABSTRACT FROM AUTHOR]

This research studies the effects of volume ratios on the properties of GO/(ZnxNi1−x)O ternary composite prepared by a sol–gel technique. The ratios were produced by keeping the volume of graphene oxide (GO) constant whilst varying the volumes of zinc oxide, ZnO and nickel oxide, NiO to produce GO/ZnO0.2NiO0.8, GO/ZnO0.5NiO0.5, and GO/ZnO0.8NiO0.2 nanocomposites. The structural, morphological, elemental, optical, gas sensing, and photocatalytic properties of the synthesized nanocomposites have been investigated. EDX results confirmed the presence of graphene oxide, nickel oxide, and zinc oxide in the composites. The bandgap energy values exhibited a reduction as compared to the constituent compounds which range from 3.1 to 3.4 eV. Functional groups belonging to carbon, oxygen, nickel, zinc were obtained. The conductivity and activation energy of the ternary composites was also determined. The gas sensing properties were tested for NH3, H2S, and Cl2 at 100 ppm and 10 V; with the highest sensitivity recorded for H2S. The synthesized ternary composites were highly effective in degradation of dye with the efficiencies of 87.3%, 86.7%, and 88.0% respectively, obtained at 0.022 per minute, 0.020 per minute, 0.024 per minute for pseudo-first order rate constant. Results from the characterization show potential application of the composites in gas sensing and photocatalytic devices. [ABSTRACT FROM AUTHOR]

The current state of transmission system design and development is greatly hampered by over voltages caused by lightning. To mitigate over voltage problems, researchers must be nearly obsessive. Since lightning strikes transmission and distribution network components like lines and substations, personnel are also seriously put in danger. Lightning prediction holds great significance, in addition to Lightning Detection Networks (LDNs) that offer ample information regarding lightning activity. Through the use of a fuzzy forecasting system, we are able to determine the chance of lightning in the low, medium, and high range. The method used to forecast lightning threats is provided by this system. [ABSTRACT FROM AUTHOR]

Metal oxides have received consideration in recent times due to their outstanding properties and diverse applications with their composites exhibiting unique electrical and magnetic features, photocatalytic degradation, and gas sensing properties. This research was carried out to investigate the properties of sol–gel synthesized (ZnxNi1−x)O binary composites since there has been no published paper yet on this. The zinc oxide, ZnO and nickel oxide, NiO samples were mixed at varied volume ratios of (0.8:0.2), (0.5:0.5), and (0.2:0.8) using Zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and Nickel (II) acetate tetrahydrate (Ni(CH3CO2)2·4H2O) as their respective precursors. A hexagonal crystal structure of the binary composite was gotten at an average crystallite size of 5.88 nm. Uniformly distributed nanolumps over the surface were observed in the morphology due to even dispersion in the Zn–Ni matrix. TEM images showed compact nanoclusters while the energy band gap values gotten were 3.2, 3.3, and 3.6 eV were obtained for the ZnO0.8NiO0.2, ZnO0.5NiO0.5, and ZnO0.2NiO0.8 composites, respectively. The functional groups present in the composites were shown in the FTIR graph with high PL counts obtained in the visible spectrum. Variation in the volume ratio of the composites gave Raman shifts at high intensity. Results obtained from the elemental analysis confirmed the presence of as-deposited elements and ascertained that the composites were synthesized in the right proportion. The composites were found to be highly sensitive most especially at high temperatures to CO2, H2S, and Cl2 at 100 ppm and 10 V. The photocatalytic efficiency obtained was above 50% at 10 ppm. [ABSTRACT FROM AUTHOR]

Quetiapine (QTP) is a moderately water-soluble biopharmaceutical classification system (BCS) class II antipsychotic drug used to treat schizophrenia. Carboxymethyl chitosan (CMC) microspheres were prepared using a co-precipitation approach. The Quetiapine was translocated to the brain through a nasal route using carboxymethyl chitosan-calcium carbonate (CMC-CaCO3) hybrid microspheres. During this process, optimization controlled the size of the microspheres by controlling the volume of solution, precipitating agent, and concentration ratios of the precursors. The optimized batch showed a narrow size distribution with high stability in the dispersed phase as characterized by dynamic light scattering. Preliminary characterization revealed crosslinking formation between the carboxymethyl groups of chitosan and the CaCO3 may be responsible for the spherical structure. The preliminary evaluations were done with Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), and UV visible spectroscopy (UV-Vis). The surface morphology was assessed by scanning electron microscopy that showed the microscale range of the spherical-shaped particles. The ex-vivo mucoadhesive studies suggested a high binding affinity toward mucin, having a sustained release effect for up to 8 h. [ABSTRACT FROM AUTHOR]

The research involves synthesizing hierarchical nanoflakes of bismuth oxide (Bi2O3) using the sol–gel (SG) method and Bi2O3 nanosheets through hydrothermal (HY) synthesis, with a focus on investigating their gas sensing and photocatalytic activity. The synthesized Bi2O3 analyzed using X-ray diffraction (XRD) techniques reveals that SG and HY are monoclinic crystal structures. Fourier-transform infrared spectroscopy (FTIR) did the functional group analysis, which shows the absorption band at 874 cm−1 and 858 cm−1 in typical stretching and bending vibrations characteristics. The surface morphology of synthesized Bi2O3 material was carried out by field emission scanning electron microscopy (FESEM), which reveals the nanosheet type morphology and one-sided arrangement like a flower by SG and HY synthesis, respectively. The gas sensing activity of Bi2O3 thick films was prepared by screen printing technique and examined for different gases such as H2S, NH3, LPG, C2H5OH, H2, CH3OH, CO2, and Cl2. They showed highest sensitivity to H2S against NH3, LPG, C2H5OH, H2, CH3OH, CO2 and Cl2. The catalyst Bi2O3 with methylene blue (MB) dye showed better photocatalytic performance of the SG method than HY synthesis. [ABSTRACT FROM AUTHOR]

This study aimed to develop esomeprazole-loaded zinc-pectinate-Sesbania gum floating microbeads, optionally supplemented with calcium silicate, as a gastro-retentive drug delivery system. The microbeads were produced using the ionic gelation method, with zinc acetate as the crosslinking agent, and were characterized through in vitro studies. The findings revealed that all formulations exhibited high drug encapsulation efficiency and sustained drug release profiles. Polymer ratios, calcium silicate incorporation, and the choice of low-density oils significantly influenced drug encapsulation efficiency and release kinetics. Notably, the B:6 batch, formulated with Sesbania gum and low methoxy pectin, demonstrated outstanding performance, releasing 95.89 ± 1.66% of the drug within 7 h, with a floating lag time of 1.18 ± 0.07 min, indicating promising in vitro gastro-retention capabilities. Analysis of P-XRD, FT-IR, SEM, and DSC data highlighted changes in crystallinity, drug--excipient compatibility, surface morphology, and thermal behavior of esomeprazole and esomeprazole-loaded microbeads. In conclusion, these floating microbeads represent a potential gastro-retentive drug delivery system, offering enhanced buoyancy and prolonged drug release, with potential therapeutic advantages for peptic ulcer management. [ABSTRACT FROM AUTHOR]

Nonlinear phononic materials enable superior wave responses by combining nonlinearity with their inherent periodicity, creating opportunities for the development of novel acoustic devices. However, the field has largely focused on reversible nonlinearities, whereas the role of hysteretic nonlinearity remains unexplored. In this work, we investigate nonlinear shear wave responses arising from the hysteretic nonlinearity of frictional rough contacts, and harness these responses to enable programmable functions. By using a numerical approach, we solve the strongly nonlinear problem of shear wave propagation through a single contact and a periodic array of contacts, accounting for frictional effects. Specifically, the Jenkin friction model with experimentally obtained properties is used to capture the effects of stick-slip transition at the contacts. Results show that friction gives rise to shear-polarized eigenstrains, which are residual static deformations within the system. We then demonstrate how eigenstrain generation in multiple contacts can enable programmable functionalities such as an acoustically controlled mechanical switch, precision position control, and surface reconfigurability. Overall, our findings open new avenues for designing smart materials and devices with advanced functionalities via acoustic waves using the hysteretic nonlinearity of frictional contacts. [ABSTRACT FROM AUTHOR]

This study aims to develop quetiapine (QTP)-loaded β-cyclodextrin (β-CD) based co-polymeric thiolated polyethylene glycol-poly(lactic-co-glycolic acid) (t-PEG-PLGA) nanoparticles (QTP@β-CD-t-PEG-PLGA) by transesterification process. As a result, the ex-vivo bioadhesion study shows good bioadhesion because of the thiolation of PEG (t-PEG), which can interrelate through mucin and expand the retention time. In-vitro release study demonstrates the QTP release to 20 h (∼98.76%). Herein, sulfhydryl ligands can form disulfide bonds with cysteine-rich mucus areas that increased the viscosity of mucin and accordingly drug retention. Hence, it can be significant accomplishment for nose to brain drug targeting in psychotic disorder management. [ABSTRACT FROM AUTHOR]

Ethyl acetate (EtAc) reactive distillation (RD) configurations often use atmospheric pressure, and this operating pressure can be reduced further to conserve energy based on the condenser cooling water temperature. Using the Aspen Plus simulator, two proposed configurations, RD column with stripper and pressure swing reactive distillation (PSRD), were simulated at lower operating pressure. The impact of RD column operating pressure on total energy usage and total annual cost (TAC) was studied. All design parameters were optimized using sequential iterative optimization procedures and sensitivity analysis to minimize the energy cost while maintaining the required product purity at 99.99%. The simulation results showed that the RD column with a stripper is better than PSRD with a saving of 23.17% in TAC and 31.53% in the specific cost of EtAc per kg. Compared to literature results, the proposed configurations have lower reboiler duty requirements and lower cost per kg of EtAc. [ABSTRACT FROM AUTHOR]

The changeable nature of renewable sources creates difficulties in system security and stability. Therefore, it is necessary to study system risk in several power system scenarios. In a wind-integrated deregulated power network, the wind farm needs to submit the bid for its power-generating quantities a minimum of one day ahead of the operation. The wind farm submits the data based on the expected wind speed (EWS). If any mismatch occurs between real wind speed (RWS) and expected wind speed, ISO enforces the penalty/rewards to the wind farm. In a single word, this is called the power market imbalance cost, which directly distresses the system profit. Here, solar PV and battery energy storage systems are used along by the wind farm to exploit system profit by grasping the negative outcome of imbalance cost. Along with system profit, the focus has also been on system risk. The system risk has been calculated using the risk assessment factors, i.e., Value-at-Risk (VaR) and Cumulative Value-at-risk (CVaR). The work is performed on a modified IEEE 14 and modified IEEE 30 bus test system. The solar PV-battery storage system can supply the demand locally first, and then the remaining power is given to the electrical grid. By using this concept, the system risk can be minimized by the incorporation of solar PV and battery storage systems, which have been studied in this work. A comparative study has been performed using three dissimilar optimization methods, i.e., Artificial Gorilla Troops Optimizer Algorithm (AGTO), Artificial Bee Colony Algorithm (ABC), and Sequential Quadratic Programming (SQP) to examine the consequence of the presented technique. The AGTO has been used for the first time in the risk assessment and alleviation problem, which is the distinctiveness of this work. [ABSTRACT FROM AUTHOR]

Lack of safe water prevents 42 percent of the world's population from accessing sanitation. In 2021, the WHO estimated that there would be 784 million people without access to safe drinking water. With a well-planned system, the group aims to cut the number of people in need of drinkable water by half by 2015. These methods improve saltwater, which makes up 97 percent of the world's water. In this regard, a model that simulates the work of groundwater treatment firms using natural resources and renewable energy has been developed. There was a lack of continuous wind energy throughout most of Oman, where this model was put, and the necessity for a reverse osmosis system for constant maintenance because these projects rely on renewable energy everywhere. This article aims to create an autonomous desalination plant powered by solar and wind energy. A simulator model based on renewable energy groundwater purification systems was created for this aim. To treat subterranean water in distant areas of Oman using two renewable technologies to create enough electricity to run the reverse water purification and water purification system at the lowest cost. A turbine mounted vertically with a height of 1.5 meters and a diameter of 1 meter will produce 2304 liters per day and 800000 liters per year. [ABSTRACT FROM AUTHOR]

The integration of renewable energy generation affects the operating characteristics of a power system, such as electric losses, voltage profile, generation cost, system stability, and reliability of the system. The installation of renewable energy generation units in non-optimal locations may increase system losses, costs, voltage fluctuations, etc. The main hurdle in integrating renewable energy generation units with an existing electrical grid is the uncertainty of renewable sources. This paper presents the impact of wind farm integration on the system economy in a wind-integrated deregulated power market. The importance of deregulation in terms of the system generation cost, bus voltage profile, and locational marginal pricing (LMP) are also studied in this work. LMP is the main parameter responsible for handling the system economy (i.e., profit of generating units and profit of customers). Considering the variable nature of wind flow, three different real-time wind speed datasets are used to validate this work. Bus sensitivity factor (BSF) is considered for equating the optimal position of the wind farm in the integrated system. Five different optimization techniques, i.e., sequential quadratic programming (SQP), artificial bee colony (ABC) algorithms, particle swarm optimization (PSO), ant colony optimization (ACO) algorithm, and slime mold algorithm (SMA), are introduced to solve the optimal power flow problem. The SMA and ACO are used for the first time in this type of economic assessment (i.e., impact valuation of LMP) in a deregulated power system, which is the novelty of this work. The entire work is performed in a modified IEEE 30 bus test system. [ABSTRACT FROM AUTHOR]

Phononic materials are periodically arranged building blocks in the form of material properties, geometries, and/or boundary conditions. This synthetic architecture makes phononic materials capable of manipulating mechanical waves that have potential applications across multiple disciplines of physics and engineering. Initial studies have been focused on linear phononic materials that assume small-amplitude waves. The incorporation of nonlinearity, however, has been shown to open opportunities for a new realm of dynamic responses valid beyond the small-amplitude regime. Acknowledging this potential, research in the field has undergone a paradigm shift in the last decade or so by exploiting various sources of nonlinearities within phononic materials. A comprehensive overview of the origin of nonlinearities and how they are modeled, solved, and realized in phononic materials, and specifically, what role nonlinearity plays in enabling rich nonlinear wave responses, is crucial for the future advancement of the field. In this review, we discuss recent advances in nonlinear wave propagation in phononic materials and metamaterials by drawing links between different phononic media and their nonlinearity-induced behaviors. We first briefly discuss the analytical methods employed to solve nonlinear wave propagation problems by focusing on foundational models. We then review physics-based sources of nonlinearities, primarily, material, geometric, and contact nonlinearities and elucidate nonlinear wave responses enabled by them in phononic materials and metamaterials. Finally, we outline existing challenges and possible future directions in nonlinear phononics and metamaterials. [ABSTRACT FROM AUTHOR]