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The effect of using citrate-gel auto combustion method to substitute erbium rare-earth ion on magnetism cadmium composition of chemicals formula Cd0.2Mg0.8ErxFe2-xO4 (CMEF) (x = 0.000, 0.005, 0.010, 0.015, 0.020, and 0.025). Synthesized powder were sintered for 4 h at 600 °C after the crushed powders were calcined. These CMEF nanoferrites' structural and magnetic properties were investigated using P-XRD, E-DAX, FE-SEM, HR-TEM, FT-IR, and VSM investigations. Analysis has been done on the benefits of the crystallite size, phase, and various structural features of CMEF using P-XRD data. The assessed crystalline size is within the range of 20.43 nm and 24.30 nm, while the lattice constant ranges from 8.34 to 8.37 Å. photos obtained with the HR-TEM showed that the Er3+ doped Mg-Cd nanoferrites had particle sizes between 10.5 and 20.7 nm, while the FE-SEM photos showed grain sizes between 19.3 nm and 40.3 nm. With the help of elemental analysis (%) from EDAX, and the CMEF of elements that comprise the given chemical composition were thoroughly analysed without interfering substances. The spinel structure was confirmed by the presence of two stretching bonds between metal nitrates and function groups, as shown by the FT-IR spectra that were obeyed. VSM generates the characteristic hysteresis loops of the synthesised sample at 300 K temperature in the magnetic experiments. The findings showed that at 300 K, all of the MCEF nanoferrites exhibited ferromagnetic behaviour. Substantial magnetization was reached at 300 K for 20–18.48 emu/g). The Hc values were determined to lie between 107.46 and 129.53 Oe, while the squareness or remanent ratio values at 300 K varied. [ABSTRACT FROM AUTHOR]

This paper focuses on a grid-incorporated solar electric vehicle (EV) charging station that maximizes the acceptance of EVs in agricultural areas and reduces the over-reliance on the grid of urban cities. Since photovoltaic (PV) systems are widely available and easy to install, they are an excellent choice for EV charging applications. Hence, the aim of this work is to combine PV and EV, in order to achieve the objectives of both decarbonized energy generation and transportation. A Modified Zeta Integrated Luo Converter (MZILC), which provides a large conversion range combined with lower voltage stress, is proposed intending to increase the voltage level of the PV system. Furthermore, the converter generates a stable output devoid of fluctuations with the usage of the Grey Wolf–Grasshopper Optimized Proportional Integral (GW-GOPI) controller. Electricity for BLDC motors is generated by PV power during the day and supplied by a single-phase grid at night. The efficiency of the suggested grid-connected PV-based EV charging station is examined in MATLAB environment. [ABSTRACT FROM AUTHOR]

This paper portrays the effect of growth rate on the structural, magnetic, and electrical properties of sputtered Ni thin films. Seventy-five nanometer thick Ni films were grown on Si <100> substrates at room temperature by high power impulse magnetron sputtering with varying growth rates such as 0.27, 0.57, 1.01, 2.18, and 2.65 Å/s. All the films crystallized in a single FCC type structure devoid of any impurity phase. With an increase in the growth rate, the density of the Ni films was found to increase. The surface roughness and the stresses developed in Ni films were found to decrease with an increase in the growth rate. Microstructural investigations indicated an island of surface morphology for all the films. An increase in growth rate was also found to affect the magnetic properties of Ni thin films considerably. Saturation magnetization increased with an increase in growth rate both along the in-plane and out-of-direction owing to the increase in the density of the film and reduction in stresses and surface roughness. Further, the in-plane magnetization studies also showed an increase in in-plane magnetic anisotropy in Ni films with an increase in growth rate. Evidences for improvement in the in-plane magnetic anisotropy were derived from the increase in the in-plane coercivity and remanence. Temperature variation of electrical resistivity in Ni films indicated a metallic behavior. Films grown at higher growth rates exhibited high-temperature co-efficient of resistance suitable for resistance temperature detector applications. [ABSTRACT FROM AUTHOR]

This study delves into an exploration of both electrical and magnetic characteristics exhibited by the Y3Fe5O12 (YIG) and Bi-modified YIG (Bi0.2Y2.8Fe5O12; BYIG) materials, which were prepared through the process of solid-state route. The crystal structures of all the synthesized materials were confirmed, using X-ray diffraction analysis which confirms the formation of a single-phase cubic structure. Energy-dispersive X-ray spectroscopy confirmed that the sample does not contain any impurities other than the constituent elements. The crystallite SEM images of Bi-modified YIG (BYIG) have shown bigger granular grains with uniform distribution. X-ray photoelectron spectroscopy measurements were also performed to understand the origin of oxygen vacancies and their chemical surrounding of Fe2+ and Fe3+ ion concentration. Detailed impedance spectroscopic studies were made in the frequency range of 100 Hz to 1 M Hz at different temperatures (RT-625 K). The broad dielectric peak observed near 473 K confirms the diffused phased transition (DPT) of the sample. From magnetic hysteresis studies, all samples have shown the saturation magnetization of 20 emu/g at room temperature. A combined electrical and magnetic study reveals the inheriting magneto-dielectric characteristics of BYIG. The results were corroborated by the Raman spectroscopic plots. [ABSTRACT FROM AUTHOR]

The All of Us (AoU) initiative aims to sequence the genomes of over one million Americans from diverse ethnic backgrounds to improve personalized medical care. In a recent technical pilot, we compare the performance of traditional short-read sequencing with long-read sequencing in a small cohort of samples from the HapMap project and two AoU control samples representing eight datasets. Our analysis reveals substantial differences in the ability of these technologies to accurately sequence complex medically relevant genes, particularly in terms of gene coverage and pathogenic variant identification. We also consider the advantages and challenges of using low coverage sequencing to increase sample numbers in large cohort analysis. Our results show that HiFi reads produce the most accurate results for both small and large variants. Further, we present a cloud-based pipeline to optimize SNV, indel and SV calling at scale for long-reads analysis. These results lead to widespread improvements across AoU. Using All of Us pilot data, the authors compared short- and long-read performance across medically relevant genes and showcased the utility of long reads to improve variant detection and phasing in easy and hard to resolve medically relevant genes. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR)-emitting phosphors are in high demand owing to their application in areas of high importance, such as security, night-surveillance, imaging, storage, and optoelectronics. However, to achieve high success in these applications, wide broadband NIR emissions are needed and, in that context, the crystalline field of the host matrix plays a very important role. In this work, we have achieved a broad NIR emission in the range of 700–1000 nm in hydrothermally synthesized SrHfO3:Cr3+ (SHOC). SHO assumes a microcrystalline cube morphology, and chromium doping make it more and more symmetric, and the particle size increases with doping. Broadband NIR emissions have been ascribed to the stabilization of Cr3+ in a strong crystalline field of HfO6 octahedra. X-ray photoelectron spectroscopy supported this by confirming the formation of oxygen vacancies in all the samples. The shorter lifetime (~13–44 µs) is attributed to chromium ions situated in close vicinity to oxygen vacancies at distance X, whereas the longer-lived (~56–127 µs) originate from chromium ions situated at a long distance from oxygen vacancies at distance Y, and Y is greater than X. Positron annihilation lifetime spectroscopy suggested an increase in defect concentration with doping, which causes concentration quenching beyond 2.0 mol% endowed by multipolar interactions. This work culminates the very important role of defects, local site, and doping on efficient NIR light emissions from a perovskite lattice. [ABSTRACT FROM AUTHOR]

In this work, we have fabricated hybrid heterojunction solar cells with structure ITO/ZnO/P3HT:PCBM:CTSe NCs (optimized weight percentage 10 wt%)/MoO3/Ag (device SM10). A thin layer of molybdenum oxide MoO3 prepared by peroxomolybdic acid organosol as the precursor was used as hole transport layers (HTLs). The performance of the device was compared with ITO/ZnO/P3HT:PCBM:CTSe NCs/Ag(device S10). The important parameters such as global charge carrier mobility (µ), effective charge carriers lifetime (τn) and charge diffusion time (τd) have been extracted from electrochemical impedance spectroscopy (EIS) performed at the bias of 0.1 V in the dark. The Nyquist plot obtained from EIS has demonstrated effective carriers lifetime, global mobility and charge diffusion time for a device SM10 as 6.46 ms, 12.6 × 10−4 cm2 V−1 S−1 and 5.2 µs and for device S10 as 5.65 ms, 9.58 × 10−4 cm2 V−1 S−1 and 6.8 µs, respectively. [ABSTRACT FROM AUTHOR]

The effect of bottom topography and a surface-piercing porous barrier on the hydroelastic response of an elastic plate floating on a two-layer fluid with variable bottom topography is studied using small amplitude wave theory. As a mathematical tool, Galerkin's single-mode approximation for waves in each layer is used for variable bottom topography, while the method of eigenfunction expansion is applied for the fluid region of a uniform bottom. In the variable bottom topography, a system of differential equations is solved. By applying matching conditions, jump conditions, and the appropriate boundary conditions, the solution is expressed as an algebraic linear system from which all the unknown constants are computed. The effects of different parameters related to the fluid, bottom topography, and porous barrier on the bending moment, shear force, and the deflection of an elastic plate are explored. The variations in the bending moments, shear forces, and plate deflection with respect to fluid density are found to be in opposite trends, caused by surface and interfacial waves, respectively. Further, as the density ratio becomes closer to one, the bending moments, shear forces, and plate deflection tend to diminish for interfacial waves. The plate is least deformed by surface and interfacial waves in the case of a concave down and a plane sloping bottom, respectively. This deformation can further be reduced by using suitable barriers as reported in this investigation. The observations may be useful in analysing the response of very large floating structures to the presence of undulating bottoms. [ABSTRACT FROM AUTHOR]

Cucurbiturils are magnificent macrocycles that are used as precise molecules for the fabrication of supramolecular chemotherapeutic agents through host-guest molecular recognition. In the present work, the host-guest complex of cucurbit[6]uril (CB[6]) with 5-fluorouracil (Flu, an anticancer drug) is synthesized and its structural study was carried out using UV, XRD, and TG/DTA techniques. The UV-Vis spectrum of the inclusion complex exhibited maximum absorbance with a blue shift at 302 nm whereas the maximum absorbance for free CB[6] was observed at 318 nm. This notable shift in wavelength proves the formation of the inclusion complex of CB[6] with fluorouracil. The host-guest complex of fluorouracil with CB[6] shows sharp endothermic peaks at 403.30C with a heat flow of -0.5 mW/mg the peak covers partially an area of 528.2 J/g, The large variations observed in the DSC curves of the complex compared with free host CB[6] confirm the formation of a stable host-guest complex. The XRD pattern of the host-guest complex is different from the parent compound and this reaffirms the formation of host-guest complex. The cytotoxic effect of 5-fluorouracil and the host-guest complex of CB[6] with fluorouracil on KB cells was determined by MTT assay and the cytotoxicity of anticancer drug Flu towards cancer cells significantly increases by encapsulating 5-fluorouracil into the hydrophobic cavity of CB[6], The ROS generation study was carried out by measurement of intracellular ROS using fluorescent and chemiluminescent probe. The ROS generation of anticancer drugs against cancer cells is significantly increased by encapsulating 5-fluorouracil into the hydrophobic cavity of CB[6], The inclusion complex of cucurbituril with fluorouracil treatment in KB cells showed higher anticancer potential than fluorouracil treatment in KB cells when compared to the control. The IC50 value of 5-flurouracil was found to be higher compared to the inclusion complex of cucurbituril with fluorouracil. The interesting results obtained, might open new avenues for the use of CB[6] host-guest complexes in anticancer and drug delivery studies. [ABSTRACT FROM AUTHOR]

The primary factors in the radiation exposure received by the human population from soil and water are natural radioactivity, uranium isotopes, and thorium isotopes. High levels of nuclear radiation exposure are now one of the leading causes of cancer. Radon and its offspring in the biosphere have long been the topic of research. Various experts from all over the world have undertaken several investigations on the quantity of radon in surface and groundwater supplies. An attempt was made to measure the levels of radon in groundwater in and around Areekode using a smart radon monitor (SRM) developed by the Baba Atomic Research Centre (BARC) in Mumbai. Groundwater/Bore well water in this region had 222Rn in concentrations ranging from 0.37±0.03Bq/L to 3.53±0.10Bq/L. The environmental protection agency's allowable limit of 11.1 kBq/m3 was met by all of the samples. [ABSTRACT FROM AUTHOR]

The effect of repeated thermal cycling (heating, soaking and cooling) between the room temperature and 360 °C on fracture toughness of hydrided Zr–2.5Nb pressure tube alloy was studied. The number of thermal cycles, hydrogen content and soaking time at peak temperature was varied. The fracture toughness at ambient temperature was determined for the thermally cycled material, which was higher than that of the as-hydrided samples that were not subjected to thermal cycling. It was also observed that the enhancement of fracture toughness was significant for the first thermal cycle and with further increase in number of thermal cycles, the fracture toughness values did not change much. The soaking time at peak temperature was observed to either increase or decrease the fracture toughness depending on the hydrogen concentration and presence or absence of hydrides at the peak temperature. [ABSTRACT FROM AUTHOR]

Unlike the ground-based manipulator, the space manipulator has no fixed base. Dynamic reaction forces and moments induced by manipulator motion will disrupt the space robot base. The docking of a floating object adds a control problem because it affects the pose of the free-floating base of the space manipulator. As a result, the tracking trajectory by the robot tip cannot comply with the reference trajectory. Owing to the non-holonomic features of space manipulator, the control methodology requires the advanced controller to neutralize trajectory deviation. This work presents the trajectory control strategy of two redundant planar robot (RPR) that dealt with a rectangular floating body. The control strategy composed of Proportional Integral Derivative (PID) controller and Amnesia controller. The eight-links two RPSR are modeled and simulated for docking the rectangular floating body. The result of computer simulation shows that with PID and Amnesia controller, the deviation between the reference and actual trajectory is decreased, the error between the reference and the actual trajectory is reduced, and the rotation of a floating rectangular body is reduced to the minimum extent because of PID and Amnesia controller. Additionally, optimum tuning of gain parameters is implemented using a Genetic Algorithm which results in further reduction of error by 40%. Furthermore, this proposed control strategy will be extended to achieve the desired trajectory by controlling and switching over various joints with greater accuracy. The Bond Graph Technique (BGT) is utilized in this work to model the robot dynamic behavior and to implement the control scheme using the SYMBOLS Shakti software. The BGT is convenient for the modeling and simulation of systems with a different domains like hydraulic, mechanical, electrical, etc. The technique generates dynamic equations based on graphical modeling with kinematic entities. [ABSTRACT FROM AUTHOR]

Objective of this study was to fabricate the microwave absorbing structures (MAS) with structural properties in X and Ku bands. Glass fibre reinforced plastic (GFRP) epoxy composites have excellent specific stiffness and strength to weight ratio. Milled carbon fibres (MCF) have been added as filler to bring functionality in GFRP composites, which causes dielectric loss. MAS were fabricated with variable wt% (2.5–7.5%) of MCF in glass epoxy composite system. The electromagnetic properties were measured in X and Ku bands using free space measurement system. Mechanical properties such as tensile strength, flexural strength and interlaminar shear strength of fabricated composites have been evaluated as per the relevant ASTM standards. The results show that the matching frequency of the microwave absorber shifts towards lower side of frequency band by increasing thickness, and reflection loss decreases with increase in MCF wt%. [ABSTRACT FROM AUTHOR]

New wireless IoT technology provides smart pseudo intelligent solutions that will have a big impact on the infrastructures and the society in the future to come. In the last decade, many new low power longrange wireless technologies have emerged to support these wireless IoT based solutions. One of the most promising and commonly accepted technologies is LoRaWAN. Unfortunately, the introduction and deployment of a new wireless technology provides new risks and new security challenges. Some of these challenges can be categorized as "critical", which means that if they fail, this will have major consequences for the society's critical infrastructure and the society as a hole. In this paper one of these critical challenges is analyzed in terms of wireless jamming attacks that cause fatale denial-of-services on the LoRaWAN wireless infrastructure and connectivity. This analysis is based on a mathematical simulation model which is described and elaborated. By using this model on a selected societal critical service example, a sensitivity analysis in terms of jamming and DoS attacks is performed, provided, and elaborated. Finally, some selected prevention strategies to avoid and counter-fight these attacks are presented, discussed, and elaborated. [ABSTRACT FROM AUTHOR]

Aurivillius intergrowth multiferroic phases are inspiring to many researchers owing to their scientific and technological application point of view. We have synthesized the intergrowth of promising three-layered Bi3.25La0.75Ti3O12 (BLT) and four-layered Bi4NdTi3Fe0.7Co0.3O15 (BNTF) compounds. The X-ray diffraction (XRD) data was analyzed by comparing our data with a standard eight-layered compound (Bi9Ti6FeO27) and the lattice parameters were evaluated. Showing a shoulder peak at maximum XRD intensity peak (1 1 8) is considered to be a signature of intergrowth formation. Scanning electron microscopic images have shown non-uniform disk-like grains with no preferential orientation. In order to extract information about relaxation species, Nyquist plots (Cole–Cole plots) were drawn at different temperatures. AC activation energies were evaluated from σ ac vs. 1000/T plots, drawn at 10 kHz, 50 kHz and 100 kHz. Based on the impedance studies it is concluded that the hopping mechanism prefers through the doubly ionized oxygen atom vacancies and this phenomenon is corroborated to dielectric relaxation. Room temperature magnetic measurements display a weak ferromagnetic order. The intergrowth compound (BLT–BNTF) displayed ME coefficient (= 0.123 mV/cm–Oe) at lower magnetic fields. This is the most striking factor and helpful to fabricate room temperature Magnetoelectric sensors. [ABSTRACT FROM AUTHOR]

In the last 10 years, mortality from acute myocardial infarction (AMI) has not significantly decreased. This situation is associated with the absence in clinical practice of highly effective drugs capable of preventing the occurrence of reperfusion injury of the heart. Necroptosis inhibitors may become prototypes for the creation of highly effective drugs that increase cardiac tolerance to ischemic/reperfusion (I/R) and reduce the mortality rate in patients with AMI. Necroptosis is involved in I/R cardiac injury and inhibition of RIPK1 or RIPK3 contributes to an increase in cardiac tolerance to I/R. Necroptosis could also be involved in the development of adverse remodeling of the heart. It is unclear whether pre- and postconditioning could inhibit necroptosis of cardiomyocytes and endothelial cells. The role of necroptosis in coronary microvascular obstruction and the no-reflow phenomenon also needs to be studied. MicroRNAs and LncRNAs can regulate necroptotic cell death. Ca2+ overload and reactive oxygen species could be the triggers of necroptosis. Activation of kinases (p38, JNK1, Akt, and mTOR) could promote necroptotic cell death. The interaction of necroptosis, apoptosis, autophagy, ferroptosis, and pyroptosis is discussed. The water-soluble necroptosis inhibitors may be highly effective drugs for treatment of AMI or stroke. It is possible that microRNAs may become the basis for creating drugs for treatment of diseases triggered by I/R of organs. [ABSTRACT FROM AUTHOR]

The interaction between an oblique gravity wave and a partial porous flexible plate barrier in a two-layer fluid with an undulating bottom has been studied using small amplitude and structural response theory. Separate cases for (a) scattering of wave and (b) trapping of wave by porous flexible plate in the presence of an impermeable sea wall are discussed. The submerged plate of two typical configurations, bottom standing and surface piercing, is considered. The effects of surface waves, interfacial waves, and the induced energy among the layers due to undulated bottom have been taken into consideration. An approximation technique, i.e. modified mild-slope equation and the Fourier method together with the method of least-square, is adopted as a solution procedure. By applying the continuity condition and mass flux at the interface along with the plate boundary conditions, the problem is converted into a system of equations. Different physical characteristics are investigated, including reflection and transmission coefficients, wave load on the plate and impermeable sea wall, and bottom effect against parameters like incident wave angle and bottom slope length. This study finds that bottom-standing plate dissipated much surface wave energy, whereas the surface-piercing plate dissipates much interfacial wave energy. An opposite effect of surface and interfacial waves on membrane deformation for any given bottom, with maximum deformation due to propagating wave along surface and interface for plane and sinusoidal bottoms, respectively, is observed. The influence of undulated sea bottom on surface wave generated force upon sea wall is almost insensitive, whereas interfacial wave-induced force on sea wall varies significantly with changing bottom profiles. The study carried out in this article holds good potential in deepening our understanding of wave scattering and trapping by a partial porous flexible barrier. [ABSTRACT FROM AUTHOR]

The present study focuses on synthesis of novel high-performance acrylic acid (AA) grafted polyethersulfone (PES) ultrafiltration (UF) membranes for purification of small therapeutic biomolecules such as urea, insulin, and cobalamin. The membranes were indigenously synthesized by adding polyethylene glycol (PEG) of 6 kDa M.Wt. as a pore former and subsequent grafting of AA using 2 to 6 wt.% concentrations under UV-induced photo grafting. Scanning electron microscopy reveals that the PEG additive profoundly influences the pore density on the membrane surface. FTIR spectra confirm the graft polymerization of AA with the PES substrate. Separation performance of the grafted membranes was evaluated to establish the trade-off between the degree of grafting and MWCO. From the experimental results, the pure water flux (PWF) of 6% grafted PES membrane was enhanced from 8.5 (PES [0] [6]) to 18.20 l m−2 h−1 (PES [6 +] [6]) in the presence of PEG pore former, respectively. The grafting concentration window of 2–6% resulted in selective membranes to altogether remove uremic toxins into the permeate with retention of high molecular size proteins. Hence, 5 and 6 wt.% AA grafted membranes exhibited > 90% rejection for insulin and cobalamin biomolecules along with 24.5 and 23.8 l m−2 h−1 bar−1 permeability towards urea, respectively. The process results correlate well with the MWCO values of membranes ranging from 1 to 10 kDa. This work provides the efficacy of these grafted membranes for potential application in the downstream processing of therapeutic biomolecules such as insulin and cobalamin. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and finite element (FE) simulation study on back face bulge formation in p-aramid composite, ultra high molecular weight polyethylene (UHMWPE) composite and p-aramid/UHMWPE hybrid composite under normal projectile impact. The experimental evaluation revels that the back face deformation in p-aramid/UHMWPE hybrid composite has been found 75–80 % and 16–18 % lower than the back face deformation in UHMWPE and p-aramid composite respectively. The hybrid composite with UHMWPE striking faces showed 7–13 % more deformation as compared to with p-aramid striking face. The average percentage difference in finite element simulation and experimental results has been found around 10 %. Further, it has been observed almost 20 % and 38 % more deformations for the hybrid composite of UHMWPE layers at the front and middle position respectively as compared to UHMWPE layers at back end. [ABSTRACT FROM AUTHOR]

The advent of new instrumentation techniques provides the breakthrough for Raman spectroscopy to establish as powerful non-invasive method for material characterization. In recent years, carbon-based materials and particularly nanomaterials emerged as the subject of enormous scientific and technological attention due to their outstanding mechanical, electrical and thermal properties. We present a brief account on the unprecedented opportunity of Raman spectroscopy for insight into the behaviour of electrons and phonons in carbon nanomaterials. Raman scattering techniques have been highlighted which can be exclusively used to understand the critical dependence of the ratio of sp2 (graphite-like) to sp3 (diamond-like) bonds with the physical properties of honeycomb carbon lattice. The different case studies carried out in our laboratory were included to underline the fact that the Raman is the backbone of non-destructive, fast and high-resolution characterization tool to provide the maximum structural features, lattice dynamics and electronic information in carbon materials at various length scales. [ABSTRACT FROM AUTHOR]

Crop phenology plays a vital role in crop productivity and has been emphasized as the key indicator of crop growth stages. Time-series 16 day composite of Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data from 2011 to 2018 were quantified to study the spatiotemporal and inter-annual changes in crop phenology with smoothening of NDVI curve by Savitzky–Golay filtering method to drive phenological metrics and predict the yield of cotton for the part of Maharashtra state. Two dates of Landsat-8 datasets with supervised classification-based maximum-likelihood classifier were used to generate crop inventory map. The overall accuracy of the map was 89.1% with a 0.79 kappa coefficient and further used in the generation of cotton crop mask. A correlation was established between cotton yield and the phenological metrics. A multiple regression model constructed with phenological metrics from the year 2011–2016 produced a correlation with 0.85 adjusted R2, 46.97 standard estimated error, 10–6p value. The fitted model was used to estimate the cotton yield of 2016–2018 with 82.29 kg ha−1 root mean square error, 36.13% mean absolute percentage error, and 0.81 Index of Agreement. The results have shown the potential of the model in capturing the variation in the sowing time, end of the crop season, length of growing period, peak NDVI time, peak NDVI value and amplitude in spatiotemporal scale for drought and normal years on a long-term basis. [ABSTRACT FROM AUTHOR]

This work attempts to optimize the multi-objective characteristics of wire electrical discharge machining (WEDM) in SLM-fabricated AlSi10Mg through a hybrid artificial neural network (ANN) coupled genetic algorithm approach. The SLM is unambiguously one of the most effective commercially viable successful additive manufacturing (AM) technologies that have the potential to replace many traditional methods of manufacturing. However, the highly intricate metallic support structures created in SLM are too strong to be eliminated by hands for which precision machining operations such as WEDM are widely employed for post-processing of SLM–AlSi10Mg. The Taguchi experimental design, considering the three most influencing factors, is performed to obtain micro-hardness and surface roughness results. The input factors for optimization are discharge current, discharge voltage, and pulse time-on in the WEDM process. The multi-objective optimization is performed using the ANN coupled GA approach where the ANN model has been generated first and the results of the best model are fed to GA for optimization. For this, five variants of three-layered, multi-perceptron models with feed-forward (BP) neural structures are also developed. The current model is supplemented with a Levenberg–Marquardt algorithm that uses logarithmic sigmoid (logsig) and linear (purelin) transfer functions. Finally, the response values from the best ANN model (3–10–2) are employed for multi-objective optimization using GA. The present study establishes the following optimized process parameters: 12 A discharge current, 42 V discharge voltage, and 12 µs time-on for maximized micro-hardness of 478 VHN and minimized surface roughness of 4.3 µm, both with greater than 98% confidence level. The present study reports briefly phase characterization such as the presence of Si particles, α-Al, and Mg2Si phases on the recast surface. The surface quality of the optimized specimen exhibits superior surface quality than its other experimental counterparts. [ABSTRACT FROM AUTHOR]

A series of silver-doped strontium hexaferrite with the chemical formula SrAgZFe12-zO19 (0.0 ≤ z ≤ 1.0) were synthesized by the Co-precipitation method. The crystal structure, morphology, and properties of microwave absorption with Ag concentration were studied. The structural analysis by XRD revealed that the samples are crystallized with an M-type hexagonal structure. The values of lattice parameters, the volume of the unit cell, and X-ray density are increasing with the increase of Ag doping. The least values of Rietveld refinements have confirmed a good correlation between experimental and calculated data. Hexagonal plate-like morphology was observed in SEM images and the grain size decreases with Ag doping. Microwave properties have been measured by a vector network analyzer. Real and imaginary parts of electrical permittivity dependence with the frequencies in X-band (8–12 GHz) have been studied. The Reflection loss (RL) was investigated for all samples in X-band frequencies. Maximum RL of − 21.95 dB at 10.0 GHz was observed for the composition of silver, z = 0.4. Improved RL when compared with the pure sample indicating enhanced impedance matching and attenuation constant hence the material can show maximum energy loss for the incident microwaves. The results so obtained are explained based on composition and microwave phenomena. The present studies have confirmed the nature of microwave absorption for Ag-doped strontium hexaferrite. [ABSTRACT FROM AUTHOR]

Nanocrystalline pure and erbium (Er3+)-substituted bismuth ferrite nanoparticles were synthesized by the citrate-gel auto-combustion method. Prepared powders were sintered at 500 °C for five hours in the air and characterized by XRD, TEM, and HR-TEM. X-ray diffraction (XRD) analysis showed the distorted rhombohedral structure of the ferrites. The surface morphology and particle size of the samples were observed by high-resolution transmission electron microscopy. The lattice parameter, crystalline size, X-ray density has been calculated from d-spacing. The perceived results can be explained depending on doping concentration. The temperature dependence of magnetic properties of Bi-Er nanoparticles was carried out by using a vibrating sample magnetometer (VSM). The magnetization as a function of applied field at ± 100 Oe was carried out at 3 and 300 K. Zero-field-cooled and (ZFC) and field-cooled (FC) magnetization measurements under an applied field of 100 Oe in the temperature range of 3-360 K. These measurements give the results of blocking temperature (Tb) at around 350 K. [ABSTRACT FROM AUTHOR]

Aim: To estimate the comprehensive healthcare costs of heart failure (HF) and determine the utilization of healthcare resources (HRU) for 2 years following index hospitalization. Subjects and methods: The Manipal Heart Failure Registry (MHFR) is a prospective registry analyzing the financial burden and HRU in 610 patients with HF. Costs incurred by patients during 2 years following index hospitalization were estimated, and their association with socio-demographic and clinical factors were calculated. After 54 (8.8%) in-hospital mortalities, 556 patients were followed up for 2 years. Results: The mean age of the study cohort was 65.08 ± 13.6 years, and 245 (40.2%) were females. Based on the ejection fraction (EF), 506 (82.9%) patients were diagnosed as having HF with reduced EF. Average hospital stay during index admission was 5.3 ± 2.9 days. Total expenditure during index hospitalization was INR 36.3 million and during 2-year follow-up was INR 45.2 million. Average total expenditure per patient was INR 133,663. The average out-of-pocket expense was INR 82,766 and average health insurance coverage was INR 50,896. Difference in expenditure was significant (P < 0.05) between specific groups, i.e., etiologies, genders, HF phenotypes, age groups, and healthcare insurance types. Conclusion: Healthcare expenditure of patients with HF in India is much lower than for the western counterparts. Higher utilization of healthcare resources in HF patients with ischemic etiology, non-compliant to medications, and elderly (age > 60 years) was associated with increased expenses. Interventional procedures and implantations account for the bulk of the expenses in ischemic HF patients. Trial registration number: Clinical Trial Registry of India: CTRI/2017/11/010395; National Institute of Health (NIH) clinical trial no.: NCT03157219. [ABSTRACT FROM AUTHOR]

Oblique wave scattering by a breakwater consisting of an array of thin porous walls in a two-layer ocean with varying bottom topography is investigated by using linear wave theory. Further, wave trapping is studied by considering an impermeable seawall. The entire bottom profile is assumed to be a shelf-type comprising a varying bottom of finite length and two uniform bottoms of semi-infinite lengths. Porous walls extending from bottom to free-surface are assumed at a lower water-depth level (lee side). Impingement of waves, which approach from a deeper depth level (seaside), on walls is considered. The Fourier method or method of eigenfunction expansion is applied for the uniform bottom, whereas an approximation technique, called a mild-slope equation, is used for the varying bottom. Solutions from these two methods are matched at interfaces under physical conditions. An explicit solution is derived in the form of a system of algebraic equations. The effect of several bottom configurations on wave interaction with porous walls is analyzed. Reflection and transmission coefficients and wave force on porous walls and seawall are analyzed for the parameters related to waves, bottom, and porous medium. The study reveals that porous walls are very effective in reducing wave transmission for bottom profiles dominated by waves. Wave forces on porous walls are less in the two-layer ocean than in a homogeneous ocean. In wave trapping, seawall attains higher wave-force for incoming surface waves than for incoming interfacial waves. The ratio of water-depth levels and wave incident angles are also analyzed for the mitigation of wave forces. The force on seawall increases with the increased depth ratio in surface wave incidence, while the force decreases with the increased depth ratio in interface wave incidence. The findings may be useful for coastal engineers to understand wave scattering by multiple porous structures in the stratified ocean. [ABSTRACT FROM AUTHOR]

Copper-doped M-type strontium hexaferrite particles of composition SrCuxFe12-xO19 (x = 0.0 to 1.0) through co-precipitation were synthesized. The structure of a crystal, morphology, microwave absorption, and magnetic properties of the materials were investigated in detail with Cu concentration. X-ray patterns indicated a single M-type phase for hexaferrites with x ≤ 0.6, while impurity phase in addition to M-type phase has been observed with x > 0.6. The obtained results have been explained based on composition, magnetic exchange interaction, and microwave phenomena. [ABSTRACT FROM AUTHOR]

Thiazolo[3,2-a]pyrimidines namely ethyl 2-acetyl-5-(2-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3a, ethyl 2-acetyl-5-(3-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3b, and ethyl 2-acetyl-5-(4-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3c were obtained by one pot synthesis using substituted 3,4 dihydropyrimidine2-thione (1a–1c) and 3-chloro-2,4-pentanedione in ethanol and characterized by single-crystal X-ray diffraction. The variation in the position of fluorine atom on pyrimidine nucleus and insight into the self-assembly of compounds with varied types of non-covalent interactions has great influence on crystal packing. [ABSTRACT FROM AUTHOR]

Bismuth-substituted CeO2 (Bi0.05Ce0.95O2) nanostructured material have displayed room temperature ferromagnetic behavior. The substitution of Ce ions with Bi3+ ions decreased the saturation magnetization (MS) value of CeO2. UV-Vis and photoluminescence spectroscopic analyses revealed the occurrence of defect states i.e. surface oxygen vacancies in the sample, which facilitated ferromagnetic interactions in the Bi-substituted CeO2 nanostructures. Further, the clusters in the sample could provide antiferromagnetic interaction amongst ions, which reduced the MS value of CeO2. The clusters in the annealed sample was substantiated from its ZFC/FC curve. X-ray photoelectron spectroscopy analysis revealed the presence of Bi3+, Ce3+, and Ce4+ ions in the sample. High-resolution transmission electron microscopy (HRTEM) images suggested the spherical and rod-shaped morphology for the particles. [ABSTRACT FROM AUTHOR]

The principal objectives of the present work were to improve thermo-physiological comfort and other essential functional features of the existing material. Several important thermo-physiological comfort characteristics, such as thermal resistance, air permeability and water vapour permeability in addition to the other essential functional features like bursting strength, surface resistivity, ultraviolet (UV) radiation protection and colour fastness to washing and perspiration of the knitted fabrics, which were developed for application in glacier regions were evaluated. These evaluated properties are discussed and also compared with existing Base Layer Clothing (BLC) for the selection of the best material for up-gradation of the same for soldiers deployed in glacier regions. Statistical analysis is carried out at 95 % significance level for different functional features to establish the specific trend exhibited by the knitted fabrics. While the existing BLC is made of polypropylene knitted fabric, the improved versions proposed in the present study were developed with polyester/lycra and blend of polyester/lycra and polypropylene/lycra knitted fabrics, made in terry pile (uncut) knit design. The characterization of different yarns used in preparation of these newer and existing knitted structures was carried out by analyzing their respective FTIR spectrums. The knitted structure made with blend of polyester/lycra and polypropylene/lycra was found to be superior in terms of thermal insulation, warm/cool sensation, water vapour permeability and surface resistivity. Several prototypes of BLC with both existing and modified materials were also fabricated, evaluated and the same are proposed for User Trials to bring out unambiguously the valuable merits and demerits. [ABSTRACT FROM AUTHOR]

We report here the structural and biocompatibility studies of bare nanoparticles of θ-Fe3C and its ferrofluid, prepared using pluronic acid F127 as a stabilizer. For both the cases, this carbide was compatible (~ 80% cell viability after 48 h) with A549 human lung carcinoma cells up to a concentration of 2 mg/mL which was comparable to that of its magnetic iron oxide counterparts. The X-ray diffraction and transmission electron microscopy validated its orthorhombic phase having an average particle size of ~ 6 nm. The surface property of the θ-Fe3C sample was analyzed by X-ray photoelectron spectroscopy (XPS), which designates the existence of only Fe and C. The Mössbauer spectroscopy for the sample also verified this carbide phase. The room temperature saturation magnetization for the sample at 2 T was around 78.2 Am2/kg. This value was more than that of magnetic iron oxide nanoparticles of similar size. Its ferrofluid displayed substantial temperature rise with time during the magnetic hyperthermia experiment. Consequently, the obtained specific loss power, as well as intrinsic loss power values, were 46 W/g and 0.526 nHm2/kg, respectively, at a field of 23 mT and 261 kHz. Both the values indicated its suitability for magnetic hyperthermia application. [ABSTRACT FROM AUTHOR]

1,4-dihydropyridines, namely diethyl 4-(4-fluorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate (1a), diethyl 2,6-dimethyl-4-(3,4,5-trimethoxyphenyl)-1,4-dihydropyridine-3,5-dicarboxylate(1b), and diethyl 4-(3,4-dimethoxyphenyl)-2,6-dihydroxy-2,6-bis(trifluoromethyl)piperidine-3,5-dicarboxylate (2), are synthesized by one-pot multicomponent condensation of aromatic aldehyde with ethyl acetoacetate and liquid ammonia in the presence of an ethanol-water mixture and are characterized by single crystal X-ray diffraction. The effect of a fluorine atom on the dihydropyridine nucleus give insight into the self-assembly of compounds with various types of non-covalent interactions that greatly affect the crystal packing. [ABSTRACT FROM AUTHOR]

Microwave absorbing composite containing barium hexaferrite (BaFe12O19) and reduced graphene oxide (RGO) has been synthesized for X-band (8–12 GHz). Barium hexaferrite particles are synthesized by auto-combustion reaction using citrate precursors. The synthesis process of RGO is carried out by using improved hummer's method. Different composites consisting of barium hexaferrite and RGO are fabricated by mixing of RGO and barium hexaferrite in different weight percentages followed by heat treatment. The developed composites are characterized for electric permittivity, magnetic permeability and reflection loss measurements. Three composites, namely RGO2, RGO4 and RGO6, are developed by varying weight percentage of RGO in barium hexaferrite. The saturation magnetization of barium hexaferrite is observed to decrease from 47.02 to 16.253 emu/g, with the increase in RGO content in the composite. The composite containing 6% RGO (RGO6) shows maximum value of complex permittivity. When RGO6 composite is casted into a pellet of thickness 2.1 mm, the maximum reflection loss of − 52.21 dB is achieved at frequency 10.72 GHz. Also, the − 10 dB bandwidth of RGO6 composite reached to 2.92 GHz, i.e., covering about 70% of X-band. [ABSTRACT FROM AUTHOR]

Electromagnetic absorbers based on carbonaceous materials, i.e., carbon black, polyaniline, polypyrrole, carbon fiber, etc., are prominently employed to attenuate incident electromagnetic waves. In the current work, exfoliated graphite (EG) was synthesized with swollen expanded volume from graphite flake by using a simple and inexpensive method. After synthesis, a series (8.9, 22.9, 33.3, 41.4 and 44.7 volume percentage) of EG–epoxy composites were prepared using a wet mixing method. EG and the prepared composites were characterized by x-ray diffraction analysis, field-emission scanning electron microscopy, and energy-dispersive x-ray analysis. An Agilent vector network analyzer (model PNA E8364B) was employed to compute the complex permittivity (εr = ε′ − jε″) of the prepared composites in the frequency range of 2 GHz to 18 GHz. The dielectric loss of the prepared EG–epoxy composites was quantified in terms of the loss tangent (tanδe = ε″/ε′). Their radar absorption properties were evaluated in terms of the return loss (RL), which in turn was calculated for varying thicknesses of the prepared composites using the computed complex permittivity data. The measured minimum RL was −26.4 dB for the absorber with thickness of 4.0 mm, and the bandwidth achieved was 5.2 GHz for RL ≤ − 10 dB in the effective frequency region of 8 GHz to 14 GHz. The matching frequency shifted towards downwards with increasing EG content in the epoxy thermosetting matrix according to both the calculated and measured data. Consequently, the prepared composites exhibited good complex permittivity, dielectric tangent loss, and microwave absorption and could be utilized in the design of electromagnetic interference shielding and absorbers for stealth applications. [ABSTRACT FROM AUTHOR]

Microwave absorbing composites containing strontium hexaferrite and titanium silicon carbide, SrFe12O19/Ti3SiC2 powder, were synthesized by mixing in different weight ratios. The strontium hexaferrite (SrFe12O19) particles were synthesized using low-temperature combustion. The 'as synthesized' strontium hexaferrite powder is observed to have low coercivity (255.09 G) and high saturation magnetization (45.1 emu/g). The titanium silicon carbide (Ti3SiC2) powder was synthesized by heat treatment of the precursors (Ti/Si/TiC) at 1100°C under argon atmosphere. A microwave absorbing composite is fabricated by mixing in a high-energy ball mill followed by heating of SrFe12O19 and Ti3SiC2 powders at 200°C. The maximum reflection loss of − 39.67 dB is observed at 9.46 GHz for the composite casted into pellets containing 20% Ti3SiC2 and 80% SrFe12O19 with 2-mm thickness. The bandwidth for less than − 10 dB loss is observed to be 2.77 GHz (66% of the total band). The developed magneto-dielectric composition confirmed its candidacy as a potential microwave absorbing material. [ABSTRACT FROM AUTHOR]

Silicon carbide quantum dots (SiC-QD) embedded inside the SiC thin film deposited on silicon (111) wafer is directly synthesized by modified chemical vapour deposition technique using boron-doped liquid polycarbosilane as a precursor. Subsequent microscopic characterization of the thin film exhibits the presence of QD, which is theoretically corroborated from the exciton Bohr radius. The film shows interesting visible and near-infra-red photoluminescence at room temperature with enhanced lifetime. In addition to the lifetime, the quantum efficiency in the visible emission was also enhanced substantially than what was reported previously. [ABSTRACT FROM AUTHOR]

In the present communication, the effect of Zr substitutions in cobalt oxide (ZrxCo3−xO4, where x = 0.01, 0.05, 0.1, 0.3 and 0.5) nanoparticles over their structural, magnetic and electric properties have been investigated. The nanoparticles were produced by single step microwave refluxing method. The crystallite size was found to be diminishing with increased Zr concentration. All the samples displayed weak ferromagnetic behavior. The continuous decrease of MS value of Co3O4 nanoparticles was noticed upon an increase in the Zr substitutions. AC conductivity and dielectric measurements were carried out in the frequency ranging from 10 kHz to 20 MHz. The samples with the highest zirconium concentration, i.e. x = 0.5 have shown relatively moderate conduction as well as dielectric properties. [ABSTRACT FROM AUTHOR]

Zn(1−x)CoxO nanoparticles with (x = 0.05, 0.10, 0.15 and 0.20) were prepared by combustion method. Here we report our findings on electrical properties carried out on these materials from room temperature to 500 °C. Thermopower investigations carried out on the materials resulted in Seebeck coefficient showing a transition from positive to negative values with 'x' dependent enhancements. The material that exhibits a p-type semiconductor character at room temperature translates into an n-type of semiconductor at higher temperatures beyond 90 °C marked by a first order transition. Electrical resistivity and the activation energy being interrelated are seen to decrease with rising temperature due to increase in charge carrier concentration. Dielectric constant (ε) and dielectric loss (tan δ) investigated as a function of frequency showed nearly exponential decline in their values with increasing frequency for all the samples. However temperature dependent 'ε' and 'tan δ' show a peaking behaviour at lower temperatures with increasing trend at higher temperature as a result of increase in dielectric polarization. The DMS materials being ferromagnetic at room temperature are good temperature dependent semiconductors with high dielectric constant. [ABSTRACT FROM AUTHOR]

Variations of Curie temperature and strength of magnetic phases with sintering temperature and Ni concentration is investigated in the present work. The AC susceptibility studies show a decrease in Curie temperature (TC) with an increase in Ni concentration in the samples. Comparison of Curie temperatures with the reported results reveals that samples in the present work show higher TC enabling high thermal stability. The Mössbauer spectra of nano- and sintered Ni-Zn ferrite samples were recorded at room temperature to monitor the local environment around Fe cations through Mössbauer hyperfine parameters as a function of composition and sintering temperatures. The increase in sharpness of the Mössbauer sextet with an increase in Ni concentration and sintering temperature corroborate improvement in homogeneity and ferrimagnetic ordering. The results of hyperfine parameters offer the possibility of having close view on configuring Curie temperature through monitoring hyperfine field by altering sintering temperature and/or Ni concentration. As the temperature dependence of magnetic and magnetoelastic properties is strongly influenced by the Curie temperature, the successful possible configuration of Curie temperature in the present work can be further investigated for desired sensor applications. [ABSTRACT FROM AUTHOR]

The present work reports on the relatively higher saturation magnetization values of Fe/Fe3O4 nanocomposites. For example, the nanocomposites of Fe obtained after milling for 10 h with 5, 10 and 15 wt% of Fe3O4 had displayed saturation magnetization values of 210, 238 and 216 Am2 kg–1, respectively, in contrast to 218 Am2 kg–1 of bulk Fe. Similarly, the maximum magnetization values for the nanocomposites after 20 and 30 h of milling were 215 and 190 Am2 kg–1 for the sample containing 5 and 15 wt% of Fe3O4, respectively. The values of HC and Mr suggest that nanocomposites exhibit soft ferromagnetic behaviour. The ball milling also reduced the crystallite and particle size of Fe from microndimension to nanometres. This was confirmed from X-ray diffraction, transmission electron microscopy and scanning electron microscopy analyses. The crystallite size of pure Fe decreased to 35, 20 and 19 nm, respectively, for the samples having 5, 10 and 15 wt% of Fe3O4 after 10 h of milling. The crystallite size decreased further with increased milling time. [ABSTRACT FROM AUTHOR]

SmxBi3–xTiNbO9 (SBTN) with x = 0 , 0.2, 0.4, 0.6, 0.8 and 1.0, a novel type of ceramic was prepared by a conventional solid-state reaction method. X-ray diffraction patterns confirm the formation of a single-phase, and lattice parameters were calculated based on the parent compound Bi3TiNbO9 (BTN). Well-defined grains were seen in the scanning electron microscopy pictures. A kink observed near 400°C for all the samples in the dielectric plot as well as in the stretched exponential parameter (β) vs. temperature plot reveals the dielectric relaxation of the samples. The tolerance factor (t) was found to increase with increase in the size of the A-site (Bi-site) modified ion (Sm). Impedance and modulus spectroscopic studies were conducted to understand the plausible reason for the dielectric relaxation. The relaxation was found to be well-fit with Arrhenius equation. SBTN samples showed lower dielectric loss compared to BTN. The remnant polarization, obtained from experimental, was found to be less than that of theoretically calculated polarization, using Shimakawa's formula. The proposed defect mechanism was interpreted using FTIR and Raman spectroscopic studies. [ABSTRACT FROM AUTHOR]

Applications of fiber-reinforced polymer matrix composites are increasing in aerospace industry due to their excellent characteristics such as low density, high tensile strength and modulus and fatigue strength. Its tremendous mechanical and electrical properties lead to specific applications in stealth and camouflage technology. In the present study, fabrication of functional radar absorbing structures (RAS) has been done and they are structurally characterized and analyzed. In the fabricated RAS, glass fiber is used as reinforcement and epoxy resin is used as a matrix, with various conducting and magnetic functional materials as fillers. To find out the effect of post-curing, one set of composites was prepared without post-curing and another set was prepared with post-curing. Measured properties indicated that post-cured composites have better mechanical properties than without post-cured composites. [ABSTRACT FROM AUTHOR]

In this study, nanocomposites of Ni0.5Zn0.5Fe2O4/polyurethane were prepared by melt mixing method and determined the influence of amount of Ni0.5Zn0.5Fe2O4 (0, 0.5, 1, 2, and 3 wt%) fillers on magnetic induction of segmented polyurethane composites with optimum processing conditions. The obtained nanocomposites particles of all the samples were characterized by TGA (Thermogravimetric Analysis), DSC (Differential Scanning Calorimetry), XRD (X-Ray Diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (Scanning electron microscopy) and Hysteresis measurements (P-E Loop tracer) & VSM (Vibrating Sample Magnetometer). XRD showed the strong characteristic diffraction peaks for ferrite while diffused diffraction pattern for polyurethane. Moreover on increasing nano fillers concentration causes the agglomeration in the composites owing to irregular distribution and consequently the strength of the material reduced. FTIR spectroscopy showed that the positions of peaks for distinctive functional groups of both ferrite and SPU. Micrographs showed that Ferrite/SPU nanocomposites having good dispersion of filler in matrix. [ABSTRACT FROM AUTHOR]