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Mg0.5Cu0.8ErxFe2−xO4 (through x = 0.000, 0.005, 0.010, 0.015, 0.020, 0.025 and 0.030) A series of rare earth (Er3+)-doped magnesium-copper nanoparticles with the general chemical compositions of Mg0.5Cu0.8ErxFe2−xO4 (through x = 0.000, 0.005, 0.010, 0.015, 0.020, 0.025 and 0.030) was fabricated by citrate sol–gel auto combustion technique. The fabricated materials are investigated through XRD, FE-SEM, EDS, TEM, FTIR, UV–Vis, DC resistivity, and TEP properties. The crystallite size of the samples was determined to be 33–40 nm with increased Er3+ concentration, and the XRD investigations validated the spinel cubic structure of the samples with the space group Fd-3 m. The lattice constant was found to decrease from 8.403 to 8.356 Å. The morphology of FE-SEM micrographs was found to be spherical shape. TEM micrographs show that average particle size decreases from 64 to 48 nm. The nanoparticles’ FTIR examination revealed that their ʋ1 and ʋ2 absorption bands were between 401–412 cm−1 and 547–562 cm−1. The optical band gap was measured using UV–vis spectroscopy and found between 1.81 and 2.38 eV. In Mg–Cu nano-ferrites with Er-doping, there was no noticeable increase in the elasticity moduli. With increasing Er-doping and composition, it has been found that the thermal energy needed to change the p-type Mg–Cu nano-ferrites’ behavior from semiconducting to n-type semiconducting behavior increases. Er-doped Mg–Cu ferrites demonstrate a metal–semiconductor behavior according to DC resistivity exploration. [ABSTRACT FROM AUTHOR]

The technology of citrate gel auto-combustion was utilized to create terbium-doped nanoparticles with significant amounts of zinc cobalt ferrites, whose chemical formula is Zn0.2Co0.8TbxFe2−xO4 with an X range of 0.000–0.030 (with an X step of 0.005). In order to determine X-ray diffraction (XRD), scanning electron microscopy (FE-SEM), transition electron microscopy (TEM), thermoelectric power studies, and magnetic properties at 5 K and 300 K. The XRD and TEM pictures show nanometer ranges and the cubic spinel structure, which is only phased, and verify the typical crystallite size. The lattice parameter and volume decrease with increasing density. It is strongly suggested by the data confirming the cubic spinel ferrites that two metallic bands have formed, as seen by the FTIR. The UV–Vis analysis results in a violet shift and reveals that the estimated direct band gap energy values range from 2.59 to 2.44 eV. The thermoelectric field is applied to all samples during a cooling cycle. The conduction mechanism causes sample electrons to behave like p-type semiconductors as the temperature rises. The magnetic characteristics of the hysteresis loops point to a change from hard to soft magnetic moments. To study the low-temperature magnetic characteristics, they show superparamagnetic behavior above blocking temperature (TB). The TB was created at temperatures between 190 and 219 K for all samples. [ABSTRACT FROM AUTHOR]

Neodymium rare earth (Nd3+)-doped nickel ferrite nanoparticles, chemically denoted as NiNdxFe2−xO4 (X = 0.01 to 0.10 in the step of 0.02), have been produced using the citrate gel auto-combustion method. The significant effect that adding Nd3+ to nickel ferrite had on changing the cation distribution as well as the material's structural and dielectric properties is researched and reported. The formation of crystal structures and crystalline size were investigated using X-ray diffraction. The electron microscope techniques using field emission were used to examine the microstructural characteristics, which show the production of nanocrystalline grains with spherical morphology. It is possible to utilize Raman spectroscopy to determine differences in nanoparticle phases and phase transitions. According to infrared spectroscopy, the spinel ferrite lattice system contains two absorption bands linked to tetrahedral and octahedral complexes. The substitution of Nd3+ion changes in particle size and cation redistribution. The examination of the dielectric might provide detailed knowledge of the charge transfer mechanism in the electrical conduction and dielectric polarization processes. These material's dielectric characteristics are influenced by their chemical makeup, processing technique, sintering process, and temperature. As the Nd3+ concentration rises, the dielectric loss reduces. The neodymium substitution is advantageous for electronic devices because they have reduced dielectric loss. [ABSTRACT FROM AUTHOR]

In this study, the synthesized rare earth Ce3+ ion doped Mg-Ni-Cu ferrites with composition formula Mg0.5Ni0.3Cu0.2CexFe2-xO4 (0.0 ≤ X ≤ 0.1) using solution gel auto-combustion method. Synthesized ferrite samples were systematically investigated for their structural, morphology, optical, and dielectric properties at varying temperatures and magnetic properties at room temperature. X-ray diffraction analysis confirms the formation of the cubic spinel phase with the Fd-3 m space group, and reviled the development of a secondary phase of cerium oxide CeO2 from the cerium concentration was increased to X = 0.04. The FESEM micrographs of our prepared ferrites show the nano-pores surface and spherical shape grains. EDX confirms the presence of all desired elements. FTIR studied supports the XRD finds. UV–vis spectra showing the blue shift along all samples, and Tauc plots giving the highest band gap energy of 2.54 eV were obtained for the X = 0.06 sample, and the lowest for X = 0.02 is 2.38 eV. VSM instrument was adopted to evaluate the magnetic behaviour of our prepared ferrites at room temperature. The magnetic hysteresis loop confirmed the ferromagnetic behaviour. Ce3+ substitution remarkably affected prepared material coercivity, and magnetic saturation was found between 15.22 emu/g and 22.41 emu/g. The squareness ratio of prepared material was found between 0.19 and 0.26, and it is known that the squareness ratio values fall in the range of multi-domine sates (0.05–0.5). Dielectric properties of synthesized ferrites were produced with normal ferrite plots with higher dielectric constant values. Most significantly, observed very low dielectric loss tangent values. The impedance analysis confirms the dominance of grain boundary resistance with only one semi-circle. [ABSTRACT FROM AUTHOR]

Citrate-gel auto-combustion was used to create cerium-doped nickel zinc ferrite Ni0.2Zn0.8CexFe2–xO4 nanoparticles at lower temperatures, where x = 0.000, 0.020, 0.030, and 0.040. The X-ray diffractometer was used to characterise the powders that were manufactured and sintered. The single-phase cubic spinel structure was validated by XRD samples. The observed results can be analysed and exposed depending on the chemical composition and crystalline size. The nanoparticles' crystalline size (D) ranged from 12.8 to 22.7 nm. The antibacterial efficacy of the created nanocomposites was evaluated using the auger diffusion technique. In this way, this research proposes an x = 0.00 to 0.04 nanocomposite that can reduce gram-positive and gram-negative bacterial activity on-demand for pharmaceuticals and medical nanocarriers. The 20 Hz to 2 MHz frequency range and the dielectric characteristics at room temperature were investigated using the LCR bridge. It was possible to generate phase variations in the octahedral sites as well as the hopping mechanism of electrons in the Fe2+ and Fe3+ ions. [ABSTRACT FROM AUTHOR]

Silicon (Si) has a significant influence on the cellular structure and microstructure of the aluminum (Al) foams, which in turn will notably affect their mechanical responses. Herein, the Al–Si foams are fabricated via a novel powder metallurgy foaming approaches with multiple Si contents to investigate the role of Si concentrations on the structural and mechanical properties. The results show that the certain contents of Si can not only delay the expansion process, but also increase the maximum expansion rate to improve the cellular structure. Specifically, the AlSi7 foams process the optimal comprehensive compressive properties of yield stress (4.36 MPa), plateau stress (6.02 MPa), and energy absorption capacity (3.47 MJ m−3) with the relative density of 0.15. However, excessive Si can decrease the expansion rate and deteriorate the cellular structure. Moreover, the deformation mode of the Al foams during compressive process converts from plastic mode to brittle mode by the adding of Si. Generally, the AlSi7 foams possess an excellent trade‐off between toughness and brittleness and exhibit the optimal mechanical responses. [ABSTRACT FROM AUTHOR]

The goal of multi-criteria decision making (MCDM) is to select the most appropriate of the alternatives by evaluating many conflicting criteria together. MCDM methods are widely available in the literature and have been used in various energy problems. The key problems studied in electrical power systems in recent years have included voltage instability and voltage collapse. Different flexible alternating current transmission systems (FACTS) equipment has been used for this purpose for decades, increasing voltage stability while enhancing system efficiency, reliability and quality of supply, and offering environmental benefits. Finding the best locations for these devices in terms of voltage stability in actual electrical networks poses a serious problem. Many criteria should be considered when determining the most suitable location for the controller. The aim of this paper is to provide a comparative analysis of MCDM techniques to be used for optimal location of a static VAR compensator (SVC) device in terms of voltage stability. The ideal location can be determined by means of sorting according to priority criteria. The proposed approach was carried out using the Power System Analysis Toolbox (PSAT) in MATLAB in the IEEE 14-bus test system. Using ten different MCDM methods, the most appropriate locations were compared among themselves and a single ranking list was obtained, integrated with the Borda count method, which is a data fusion technique. The application results showed that the methods used are consistent among themselves. It was revealed that the integrated model was an appropriate method that could be used for optimal location selection, providing reliable and satisfactory results to power system planners. [ABSTRACT FROM AUTHOR]

This study was undertaken to analyze the dietary pattern and nutritional status of preschool children and to check the association between diet and socio-demographic factors. Dietary Pattern of 390 preschool children from Udham Singh Nagar district of Uttarakhand state of India was assessed. 24-Hour dietary recall and food frequency questionnaire (FFQ) was used for collecting information regarding dietary intake for three consecutive days. Nutritional indices (weight for age, height for age, weight for height, and BMI for age Z score) were studied using WHO Anthro software. Results indicated that the nutrient intake was inadequate, with major children consuming less than 60% of the recommended intake. Family income, community, type of family, birth order (ordinal position), and the number of siblings were associated with dietary insufficiency (p < 0.05). Stunting and wasting were commonly prevalent in more number of girls as compared to boys, on the contrary; more boys were underweight as compared to girls. A higher proportion of girls 18% (95% C.I. 10.8, 25.3) were thin as compared to boys 15% (95% C.I. 8.4, 21.6). [ABSTRACT FROM AUTHOR]

Aquaculture based on the Internet of Things (IoT) is a growing field of interest in the fishing industry. The IoT technology is advancing the agriculture 4.0 era, and yet, Aquaculture 4.0 is a lagging field in many countries. This article presents results obtained so far from ongoing research of published work highlighting water quality monitoring in fishponds. This analysis was performed extensively from May to December 2020 by meticulously selecting a total of 30 internationally published research papers. This review is divided into five categories: (1) recent research (2011–2020), (2) aquaculture environments, (3) research approaches, (4) most common water quality parameters and (5) forms of the solution provided. Most of the published research concentrated on inland aquaculture (81%), while research articles on marine aquaculture species accounted for 19% of papers reviewed so far. The framework and architecture approach (48%) was the most widely practised research approach in IoT‐based aquaculture for water quality monitoring. There is a need for long‐term experimental research to identify the challenges and suggest appropriate solutions. With regards to water quality parameters, temperature (20%), dissolved oxygen (18%) and pH (17%) are the topmost prioritised water quality parameters considered in the IoT‐based aquaculture. Finally, real‐time monitoring (50%) is offered generally as a form of a solution while autonomous (3%) monitoring can be a unique solution. The findings from this study are expected to support the aquaculture industry, researchers, practitioners and decision‐makers in the long run. [ABSTRACT FROM AUTHOR]

Co0.5Mg0.5-xCuxFe2O4 (x = 0.0, 0.2 and 0.4) nanoferrites were prepared by sol–gel auto combustion method. XRD, FT-IR, and HRTEM studies revealed the single-phase spinel cubic crystal structure of all samples with Fd-3 m space group. The lattice constant, calculated using the XRD data, was found in the range 8.3936–8.4735 Å. The average crystallite sizes were found to be in the range of between 38.8 and 49.9 nm. The microstructural behavior and elemental composition of all samples were detected by FE-SEM and EDS, respectively. FTIR curves showed two absorption bands ʋ1 with higher frequency and ʋ2 with a lower frequency, indicating metal cation and oxygen bond stretching at tetrahedral and octahedral sites. DC resistivity was decreased with increasing the content of copper. VSM study confirmed the ferrimagnetic behavior of all samples. The values of remnant ratios obtained from VSM data showed their isotropic nature forming single domains ferrimagnetic particles [ABSTRACT FROM AUTHOR]

The paper presents issues associated with the impact of electromagnetic interference on track-side cabinets of a closed-circuit television system (CCTV) functioning in a railway transport environment. The measurements of an electromagnetic field emitted by a track-side CCTV cabinet were presented. Designs of this kind are operated in railway facilities; therefore, they should not disturb the functioning of other equipment, the rail traffic control systems, in particular (the so-called inner compatibility). An analysis of the obtained results facilitated developing a research model, and, further, improving its reliability and conducting an operational analysis, considering electromagnetic interference. This enabled us to determine a relationship allowing us to specify the probability of a track-side CCTV cabinet staying in a state of full ability. The presented discussions regarding a track-side CCTV cabinet, considering electromagnetic interference, allow us for the numerical assessment of different types of solutions (technical and organizational), which can be implemented in order to mitigate the impact of electromagnetic interference on the system functioning. [ABSTRACT FROM AUTHOR]

Copper oxide modified activated carbon (CuO/AC) composites for the CO2 capture were synthesized via a facile assembly strategy associated with a direct solid-state heat dispersion process by introducing CuO into AC using Cu(NO3)2 as the copper source. The synthesized CuO/AC composites with various CuO contents were characterized by powder X-ray diffraction, scanning electron microscopy and nitrogen adsorption-desorption measurement, and the CO2 adsorption performance was investigated. The characterization results indicate that the Cu(NO3)2 species was well dispersed into the AC pore channels and then converted to a highly dispersed CuO after the activation process. The adsorption results reveal that the CO2 adsorption performance can be significantly improved by introducing CuO onto the AC surfaces, and the CuO(0.6)/AC composite with a CuO loading of 0.6 mmol/g AC shows a high CO2 adsorption capacity and adsorption selectivity and displays an excellent reversibility. Additionally, the calculated adsorption heat values of CO2 on the CuO(0.6)/AC composite are in the range of 27.3 to 33.9 kJ/mol. [ABSTRACT FROM AUTHOR]

In this paper, a control strategy for real-time operation of a master-slave controlled microgrid is developed. The basic idea of this control strategy is to schedule all dispatchable energy sources available into a microgrid to minimize its operational costs. Control actions are centrally evaluated by solving a two-stage optimization problem formulated to take place on two different time-scales: in the day-ahead and in the real-time. The first one provides a 24-hour plan in advance. It mainly draws up the active power levels that Distributed Energy Resources (DERs) should provide for each quarter hour of the next day by taking into account energy prices of the day-ahead energy market, the forecasted energy production of non-dispatchable renewables and loads. The real-time optimization problem updates the active power set-points of DERs in order to minimize as much as possible the real-time deviations between the actual power exchanged with the utility grid and its scheduled value. The effectiveness of the proposed methodology has been experimentally tested on an actual microgrid. [ABSTRACT FROM AUTHOR]

The paper addresses the problem of placement of sectionalizing switches in medium voltage distribution networks. Proper placement of sectionalizing switches is one of the elements leading to higher power networks reliability. The methods of optimal allocation of such switches in a MV distribution network are presented in the paper. SAIDI was used as a criterion for the sectionalizing switches placement. For selecting optimum placements, three methods were used: brute force method, evolutionary algorithm and heuristic algorithm. The calculations were performed for a real MV network. [ABSTRACT FROM AUTHOR]

Currently, the distribution system has been adapted to include a variety of Distributed Energy Resources (DERs). Maximum benefits can be extracted from the distribution system with high penetration of DERs by transforming it into a sustainable, isolated microgrid. The key aspects to be addressed for this transformation are the determination of the slack bus and assurance of reliable supply to the prioritized loads even during contingency. This paper explores the possibilities of transforming the existing distribution system into a sustainable isolated network by determining the slack bus and the optimal locations and capacity of Distributed Generators (DGs) in the isolated network, taking into account the contingencies due to faults in the network. A combined sensitivity index is formulated to determine the most sensitive buses for DG placement. Further, the reliability based on the loss of load in the isolated system when a fault occurs is evaluated, and the modifications required in for reliability improvement are discussed. The supremacy of the transformed isolated network with distributed generators is comprehended by comparing the results from conventional IEEE 33-bus grid connected test system and modified IEEE 33-bus isolated test system having no interconnection with the main grid. [ABSTRACT FROM AUTHOR]

Objective: To assess trends in nutrient intakes and nutritional status of rural adult women (≥18-60 years) and the association of sociodemographic characteristics with overweight/obesity.Design: Community-based cross-sectional studies carried out during 1975-79 to 2011-12 by the National Nutrition Monitoring Bureau (NNMB) were used. Anthropometric measurements such as height, weight and waist circumference, carried out during the surveys, were used. Association and logistic regression analyses between sociodemographic characteristics and overweight/obesity and abdominal obesity were conducted using a complex samples procedure.Setting: Ten NNMB states of India.Subjects: Non-pregnant and non-lactating rural women aged ≥18-60 years covered during the above periods from ten states in India.Results: The prevalence of chronic energy deficiency has declined from 52 % during 1975-79 to 34 % during 2011-12, while that of overweight/obesity has increased from 7 % to 24 % during the same period. Median intakes of most of the nutrients have increased over the same period, although they were below recommended levels. The chance of overweight/obesity and abdominal obesity was significantly (P<0·01) higher among women aged 40-60 years, those belonging to Christian religion and other backward communities, women living in pucca houses, literate women, women engaged in service and business, and those having higher per capita income.Conclusions: Prevalence of chronic energy deficiency has declined significantly; however, overweight/obesity has increased during the same period. This increase in overweight/obesity may be attributed to increased consumption of fatty foods, sedentary lifestyle and improved socio-economic status. There is a need to educate the community about regular physical exercise, low intakes of fats and oils, and a balanced diet. [ABSTRACT FROM AUTHOR]

During the almost 27 years of its existence, the business ecosystem research has developed a substantial level of ambiguity and multifacetedness. Because to the technological advancements that promote interconnectedness and value co-creation, the field has consequently spun off into more domain-specific branches, such as the arena of digital business ecosystems that are driven by Internet of Things (IoT). Nonetheless, despite the efforts to mend the theoretical foundations and to close the gap between academia and empirical practice, the absolute majority of IoT-driven digital business ecosystem literature follows the trend of conceptual randomness while expanding the volume of publications exponentially. Therefore, in order to address this unfavourable increase in random adoption of distinct concepts that ultimately refer to the same subject matter, the author encourages other scholars involved in the research field of IoT-driven digital business ecosystems to make extended efforts and support the external validity of their research (as well as the relevance of the research stream as a whole) by bounding the IoT-driven digital business ecosystems on a rigorous basis through deploying the extant theory in a careful and appropriate manner. Via a thorough examination of the theoretical fundaments that underpin the concept of IoT-driven digital business ecosystem, and based on a concise thematic review of corresponding literature published until September 2020, this article articulates logic for viewing the conceptual hierarchy within the business ecosystem research and proposes six literature-based recommendations for developing further IoT-driven digital business ecosystem (DBE) research in a rigorous way. [ABSTRACT FROM AUTHOR]