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Chemically stable two-dimensional nanostructured graphene with huge surface area, high electrical conductivity and mechanical excellence has gained significant research attention in the past two decades. Its excellent characteristics make graphene one of the important materials in various applications such as environmental and energy storage devices. Graphene no doubt has been a top priority among the carbon nanomaterials owing to its structure and properties. However, the functionalization of graphene leads to various nanocomposites where its properties are tailored to be suited for various applications with more performance, environmental friendliness, efficiency, durability and cost effectiveness. Graphene nanocomposites are said to exhibit more surface area, conductivity, power conversion efficiency and other characteristics in energy devices like supercapacitors. This review was aimed to present some of the applications of graphene-based nanocomposites in energy conversion devices like supercapacitors and Li-ion batteries and some of the environmental applications. It was observed that the performance of supercapacitors was obstructed due to restacking and agglomeration of graphene layers. This was addressed by combining MO (metal oxide) or CP (conducting polymer) with graphene as material for electrodes. Electrodes with CP or MO/graphene composites are summarized. Heterogeneous catalysts were of environmental concern in recent years. In this context, graphene-based nanocomposites gained significance due to expansion in structural diversity. A minimum overview is presented in this paper in terms of structural aspects and properties of GO/rGO-based materials used in supercapacitors and environmental applications like dye removal. Continuous efforts towards synthesis of productive graphene-based nanocomposites might lead to significant output in applications related to environment and energy sectors. [ABSTRACT FROM AUTHOR]

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]

Thermal energy and its storage systems play an extensive role in day-to-day life. They store renewable energy and are capable of recovering generated heat from different systems. Storage of thermal energy can be classified into three types: sensible, latent and sorption heat storages. Thermal heat storages use different types of materials based on their capacity of heat storage, stability of duration and thermal conductivity. Various phase change materials (PCMs) that are suitable for thermal storage are reported. Low conversion ability limits their effectiveness. We reviewed some of the traditional materials synthesized recently that are used for thermal energy storage (TES). Recently developed TES materials exhibit high thermal conductivity, reduced super cooling and multiple phase change temperatures. Nano-enhanced PCMs produced an increase in thermal conductivity up to 32% with a reduction in latent heat by 32%. At this juncture, MXenes with high performance and extraordinary properties (thermal, mechanical, etc.) are of special significance. MXenes displayed an increased thermal conductivity up to 16% and 94% efficiency. In view of their structure and adaptability to be used in thermal storage systems, an attempt was made to review their role also in thermal storage applications. It is observed that MXenes highly impact storage and efficiency. Apart from MXenes, various types of PCMs along with their thermal characteristics are presented. [ABSTRACT FROM AUTHOR]

Aluminum-doped Zinc Titanate (AZT) AlxZn1-xTiO3 ( for x= 0.20,0.40,0.60,0.80) nanoparticles are synthesized through low temperature hydrothermal method and their physical properties such as structure, surface, energy gap and dielectric characteristics were investigated using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), UV-visible spectroscopy and impedance analysis. XRD analysis indicated structural transformation of tetragonal phase for samples of x = 0.20 to 0.60 and some secondary phases for x=0.80. It was found that lattice constants of the sample decrease with increasing aluminium content. The morphology of nano-composites, as evidenced by FESEM and TEM imaging, displayed the formation of nano-spheres and nano-rods. The impedance and dielectric modulus analysis for the current samples revealed their dielectric behaviour, microstructure and conduction procedure. However negative dielectric property was seen in nano-composite with x=0.60. All samples with x ranging between 0.2 to 0.8 displayed high ac-electrical conductivity at 1 MHz frequency. These samples are well suitable for charge storage capacitors and as perfect absorbers. [ABSTRACT FROM AUTHOR]

In the present work, we have synthesized rare-earth ion modified Bi4−xRExTi2Fe0.7Co0.3O12−δ (RE = Dy, Sm, La) multiferroic compounds by the conventional solid-state route. Analysis of X-ray diffraction by Rietveld refinement confirmed the formation of a polycrystalline orthorhombic phase. The morphological features revealed a non-uniform, randomly oriented, plate-like grain structure. The peaks evident in the Raman spectra closely corresponded to those of orthorhombic Aurivillius phases. Dielectric studies and impedance measurements were carried out. Asymmetric complex impedance spectra suggested the relaxation of charge carriers belonging to the non-Debye type and controlled by a thermally activated process. Temperature-dependent AC conductivity data showed a change of slope in the vicinity of the phase transition temperature of both magnetic and electrical coupling natures. Based on the universal law and its exponent nature, one can suppose that the conduction process is governed by a small polaron hopping mechanism but significant distortion of TiO6 octahedral. The doping of the A-sites with rare-earth element ions and changes in the concentrations of Fe and Co ions located on the B-sites manifested themselves in saturated magnetic hysteresis loops, indicating competitive interactions between ferroelectric and canted antiferromagnetic spins. The magnetic order in the samples is attributed to pair-wise interactions between adjacent Fe3+–O–Fe3+, Co2+/3+–O–Co3+/2+, and Co2+/3+–O–Fe3+ ions or Dzyaloshinskii–Moriya interactions among magnetic ions in the adjacent sub-lattices. As a result, enhanced magnetoelectric coefficients of 42.4 mV/cm-Oe, 30.3 mV/cm-Oe, and 21.6 mV/cm-Oe for Bi4−xDyxTi2Fe0.7Co0.3O12−δ (DBTFC), Bi4−xLaxTi2Fe0.7Co0.3O12−δ (LBTFC), and Bi4−xSmxTi2Fe0.7Co0.3O12−δ (SBTFC), respectively, have been obtained at lower magnetic fields (<3 kOe). The strong coupling of the Aurivillius compounds observed in this study is beneficial to future multiferroic applications. [ABSTRACT FROM AUTHOR]

Energy storage and energy-storage devices have been a buzzword for long time as it is one of the essential needs in human life. These devices include mechanical systems, thermal systems, and batteries. These systems embedded with software can monitor the charging and discharging phenomena of energy. In this context, the role of rechargeable batteries needs to be reviewed. Even though novel types of rechargeable batteries are being continuously developed for storage of electricity, more attention and research towards supercapacitors is on the way. Huge number of researchers around the globe is involved in developing supercapacitors with improved performance making them more and more useful. The main aim is to improve their efficiency, energy density, operating voltage, miniaturization, optimization, economy, and environmental acceptance. For the last few years, lightweight and carbon-based novel wearable supercapacitors are developed. High durability, eco-friendliness, being non-volatile and electrostatic mechanism of supercapacitors make them advantageous than conventional batteries. In this regard, advances in microelectronics demand microsupercapacitors (MSCs). The selection of electrode in microsupercapacitor plays significant role in the fabrication. In this selection, MXenes as a family of 2D material play a vital role. Very high conductivity and high capacity of charge storage makes MXenes as one of the potential materials for electrodes in microsupercapacitors. This prompts us to review the role of MXenes in microsupercapacitors. This article reviews the recent advances of MXenes-based MSCs with emphasis on their fabrication techniques. [ABSTRACT FROM AUTHOR]

Liquid detection has been one of the buzzwords that refer to sensing of various liquids, which include water, chemicals, oils, etc. This detection gains more significance with the advent of metamaterials. Metamaterials are proved well suited in antenna designing, cloaking devices, solar cells, and sensors. Many papers reported metamaterial sensors, which can detect liquid chemicals, oils, etc. through shift in resonance frequency. Very few papers reported the applications of metamaterial sensors in water treatment. Water purification is one of the prime essentials for the existence of healthy humankind. It can be used to remove unwanted chemicals, contaminants and gases from water. The process of water purification can be done with various methods such as thermal, adsorption, distillation, desalination, reverse osmosis, etc. The main aim is to produce water required for specific purpose. In this context, role of metamaterials in water purification is of prime significance. Keeping this in view, an attempt is made to review the importance of metamaterial sensors in liquid detection along with water purification and its importance in comparison with earlier techniques already available. [ABSTRACT FROM AUTHOR]

MXenes are a class of 2D material produced from the MAX phase structure, e.g., 3D atomic laminate Ti3AlC2 ; they have a combination of layered carbides and nitrides. They belong to a distinctive type of structured materials with better conductivity than metals, increased ionic conductivity, flexible mechanical properties, and being hydrophilic. MXenes can be structured to form nanoparticles, multi- and single-layered nanosheets, which exhibit large specific surface areas enhancing their efficiency of sensing in MXene sensors. In addition, they are capable of forming composites with other materials with ease. Their morphology enhances their mechanical flexibility and stretchability enabling them to have wide applications in energy-storage devices, wearable sensors, and for electromagnetic shielding. Considering this, an attempt is made to review the recent advances in MXenes with emphasis on their applications in the area of wearable sensors that include pressure, strain, biochemical, temperature and gas sensing. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh during kharif, 2018 to evaluate the bio-efficacy of certain insecticides against Pectinophora gossypiella. The treatments under study were emamectin benzoate, flubendiamide, chlorantraniliprole, chlorantraniliprole + lambda cyhalothrin, deltamethrin, NSKE 5%, profenophos and cypermethrin along with one untreated control. Three sprays were given at 10 days interval and the data on larval population was collected at three, seven and ten days after spraying. The results of three sprays revealed that chlorantraniliprole + lambda cyhalothrin was effective in the control of P. gossypiella, which recorded 78.54, 85.24 and 94.36 per cent reduction larval population for 20 bolls over control at first, second and third sprays respectively followed by cypermethrin with per cent reduction of 74.03, 83.52 and 90.87 over control at first, second and third sprays respectively. Chlorantraniliprole + lambda cyhalothrin recorded highest number of good opened bolls per plant and seed cotton yield of 42.33 and 3786 kg ha-1, respectively followed by cypermethrin 25 EC (40.93 and 3662 kg ha-1) when compared to untreated control (22.40 and 2304 kg ha-1). [ABSTRACT FROM AUTHOR]

Some of the insect pests developed resistance to conventional insecticides like organochlorine, organophosphate, and carbamates. Synthetic pyrethroids and some of the molecules were restricted to use which has an undesirable effect on beneficial organisms, natural enemies and mammals, which lead to the development of novel insecticides with a unique mode of action like Chordotonal organ TRPV channel modulators nerve action GABA gated chloride channel allosteric modulators, Nicotinic acetylcholine receptor (nAchR) competitive modulators; Insect growth regulator with contact activity; Nicotinic acetylcholine receptor allosteric modulator site I; Nicotinic acetylcholine receptor allosteric modulator site II; Ryanodine receptor modulators; Inhibitors of acetyl CoA carboxylase; calcium-activated potassium channel modulator; Voltage-dependent sodium channel blockers; Chordotonal organ TRPV channel modulators – undefined target site; Inhibitors of mitochondrial ATP synthase and Mitochondrial complex III electron transport inhibitors-Qi site. Pest management now requires knowledge for agricultural production among the farmers in an economically successful manner. The major approach is to manage the insecticide resistance in insect pests by following an integrated control strategy, alternation of insecticides with a unique mode of action, application of insecticides at the correct time with the recommended dosage and targeting vulnerable stages of insect pests. [ABSTRACT FROM AUTHOR]

Anthropogenic activity in terms of urbanization, industrialization, and modern agricultural techniques challenges the natural environment in terms of compromise in air pollution and water quality, which lead to hazardous health impacts on human beings. In this context, it is very essential to monitor the air and water quality to a maximum possible extent with maximum accuracy, which is of utmost significance. A significant effect on human health due to pollutants makes their detection in water and air essential. Even though various techniques of monitoring these pollutants are available, proven advantages of electrochemical techniques attract more attention. Because of this, an attempt is made to review some of the latest advances in electrochemical sensing of environmental contaminants, which include heavy-metal ions and pesticides. Electrochemical sensing has been done by using sensors designed with various materials. However, sensors designed with carbon and its allotropes such as carbon nanotubes, graphene derivatives, carbon nanodots, active carbon, screenprinted carbon electrode, and others are reviewed. Even though these sensors are capable of being used in medical analysis, food safety, soil quality, drug detection, etc., the review paper highlights only applications related to environmental monitoring. This review is mainly meant to come up with an understanding of the present-day progress in electrochemical applications based on carbon and its allied materials towards environmental pollutants. This review highlights some of the synthesis techniques of graphene (an allotrope of carbon) and sensor designing along with their performance. This review has established the compatibility in the published literature that graphene and related materials play a significant role in electrochemical sensing of pollutants. [ABSTRACT FROM AUTHOR]

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Magnetic properties and structural analysis of Nd(Neodymium) doped Ni0.65Zn0.35Fe2O4 using XRD, Rietveld Analysis, FTIR Spectroscopy and VSM are reported. Confirmation of secondary phase formation with increased Nd content is established. Cation distribution for neodymium substituted nickel-zinc ferritesis proposed by considering the deficiency of Fe3+ in NiZnFe2O4 due to secondary phase formation of NdFeO3. The quality of present cation distribution was confirmed through close agreement of experimentally calculated lattice constant and Rietveld refinement. Changes in saturation magnetization with increased Nd content are explained on the basis of intensifying effect on energy exchange (inter-sublattice) between Ni-O-Nd and Ni-O-Fe concnerning Fe-O-Fe interaction, effect of replacing lower magnetic moment Nd3+ (3.62 μB) in place of Fe3+ (5 μB) and exchange developed between the cations existing at B-sites due to creation of oxygen vacancies. [ABSTRACT FROM AUTHOR]

Back electromotive force (EMF)-based sensorless vector control of permanent magnet synchronous motor (PMSM) drives provides a simple, robust, and low-cost solution for applications requiring only medium- and high-speed control. However, during the low-speed operation, back EMF is nearly zero, and hence, for starting and speed ramp-up, open-loop I−ƒ control is used. Once the motor attains a sufficient speed, the control is transferred to sensorless vector control. However, an arbitrary choice of the slope of frequency ramp leads to pole slipping. Pole slipping is usually prevented by fixing the frequency ramp slope to a minimum value, which deteriorates the dynamic performance during starting. In this article, a torque controller is proposed to dynamically vary the frequency slope depending on the moment of inertia and load torque present in the system, achieving fast and reliable starting. A reference frequency modulation algorithm for overcoming the inherent mid-frequency instability of the open-loop control is also included. An additional slope attenuator is proposed to minimize the torque oscillations caused by the reference frequency modulation during the transition from a ramp-up interval to a constant-speed interval with I−ƒ control. The proposed methods are experimentally verified on a 25-kW PMSM drive, which is started using open-loop I−ƒ control. [ABSTRACT FROM AUTHOR]

A study on the assessment of IPM module for the management of fall armyworm (FAW) in maize was conducted in farmer's fields in the maize growing tract of Prakasam district during 2018-19, 2019-20 and 2020-21. The mean FAW incidence of 13, 8, 6 and 4 per cent was recorded in IPM module over 32.6, 25.3, 19.3 and 14.6 per cent in farmer's practice at 15, 30, 45 and 60 days after sowing, respectively. The mean yield of IPM module was 70.68 q/ha with net returns and C:B ratio of Rs. 70048/ha and 1:2.46, respectively. Whereas, farmer's practice recorded a mean yield of 59.89 q/ha with net returns and C:B ratio of Rs. 50604/ha and 1:2.02, respectively. The increase in yield over farmer's practice was 18.01 per cent. [ABSTRACT FROM AUTHOR]

Samarium modified SrBi4-xSmxTi4O15 (x = 0, 0.13, 0.43 and 0.78) ferroelectric ceramics of Aurivillius family were prepared by conventional solid state reaction method. X-ray diffraction studies confirm the formation of a single-phase. Microstructural images show randomly oriented palate-like structure. Broad dielectric peaks were found to obey the modified Curie-Weiss law. The overall inherent ferroelectric nature was explained on the basis of the Avrami model. Furthermore, with increasing the Sm3+ content, the grain morphology and diffusive parameters have shown a comprehending impact on the ferroelectric (hysteresis) behavior. [ABSTRACT FROM AUTHOR]

An experiment was conducted at Regional Agricultural Research Station, Lam, Guntur to evaluate the field efficacy of an egg parasitoid, Trichogrammatoidea bactrae Nagaraja through inundative releases against pink bollworm, Pectinophora gossypiella (Saunders) in cotton for two successive seasons, during kharif 2016-17 and 2017-18. The mean larval incidence of pink bollworm was significantly lower in T. bactrae released plots with significant reduction in green boll damage and locule damage than untreated control, but significantly higher as compared to insecticide treated plots. Results suggest that the inundative release of T. bactrae achieved sizeable control of pink bollworm, hence it can be integrated with other control measures for sustainable management of pink bollworm. [ABSTRACT FROM AUTHOR]

In the aftermath of resistance of Bt cotton to pink bollworm in many parts of India, alternative control strategies should be worked out apart from the traditional chemical control. Use of pheromones for mass trapping and mating disruption is gaining importance worldwide rather than monitoring for pink bollworm. In present study, the field efficacy of novel pheromone formulation against pink bollworm through mating disruption techniquein BG II cotton was evaluated in a large blocks of 12 ha each during summer 2016-17 at four different locations. The SPLAT formulation @ 125 g/acre was used thrice starting from 45 DAS onwards during crop growth period which was distributed uniformly on 200 plants/acre. The male moth catch, larval density and locule damage in green bolls was reduced by 86.72%, 62.03% and 74.21%, respectively and seed cotton yield was increased by 16.89% in SPLAT treated fields when compared to insecticide treated control fields. Results showed that the SPLAT, a novel slow and sustainable pheromone release formulation is effective in reducing the incidence and damage by pink bollworm through mating disruption technique in Bt cotton. [ABSTRACT FROM AUTHOR]

In this study, we grew 5-layered SrBi4.25La0.75Ti4FeO18 (SBLFT) polycrystalline thin films (80–330 nm thick) via pulsed-laser deposition to study their ferroelectric and magnetoelectric response. Structural/microstructural analysis confirmed the formation of orthorhombic SBLFT with good crystallinity and randomly oriented Aurivillius phases. Detailed scanning transmission electron microscopy analysis of 120 nm film revealed a predominantly five-layered structure with the coexistence of four-layer stacking. Such stacking defects are found to be pertinent to the high structural flexibility of Bi-rich Aurivillius phases, alleviated by lattice strain. Raman spectral features at ambient temperatures depict the signature of the orthorhombic-tetragonal phase transition. SBLFT films have a strong ferroelectric nature (remanent polarization 2Pr of 35 μC cm−2) with a fatigue endurance up to 1010 cycles and strongly improved, switchable magnetization as opposed to its antiferromagnetic bulk counterpart. The scaling behavior of dynamic hysteresis reveals that ferroelectric domain reversal has good stability and low energy consumption. We observed the presence of SBLFT nanoregions (1–5 nm), distributed across the film, with Bi and Fe-rich compositions and oxygen vacancies that contribute to the weak ferromagnetic behavior mediated by the Dzyaloshinskii–Moriya interactions. Subtle changes in the structural strain and lattice distortions of thin films with varied thicknesses led to distinct ferroic properties. Stronger ferroelectric polarization of 80 nm and 120 nm films compared to that of thicker ones can be due to structural strain and the possible rearrangement of BO6 octahedra. The observation of the improved magnetoelectric coefficient of 50 mV cm−1 Oe−1 for 120 nm film, as compared to that of several Aurivillius oxides, indicates that the structural strain modification in SBLFT is beneficial for the fatigue-free magnetic field switching of ferroelectric polarization. The structural strain of the unit cell as well as the presence of Bi- and ferromagnetic Fe-rich nanoregions was found to be responsible for the improved multiferroic behaviour of the SBLFT films. [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]

Supervisory Control and Data Acquisition (SCADA) systems have proved to be one of the important ingredients for substation automation. Legacy SCADA architectures are based on proprietary hardware and software-based Remote Terminal Units (RTUs) with little scope for modifications and expansions. Current SCADA architectures are based on distributed systems with Intelligent Electronic Devices (IEDs) based on IEC 61850. These SCADA systems are implemented with a centralized server located at control centers for performing various substation automation functions. With this kind of architecture, a local Human Machine Interface (HMI) is normally implemented to have access to the operational data at the substation level. Certain specific software applications catering to asset management functions, which are useful for the local operators, are also implemented at the substation level. All such local applications have to access data from IEDs, legacy RTUs, etc., called hardware nodes. Since these hardware nodes follow different communication interface methods, the software applications running in the desktop computers also have to adopt hardware-specific communication interface routines. Fast and reliable data transfer among these heterogeneous systems coupled with seamless integration to host applications is a technical challenge. The paper presents a generic Soft Data Bus (SDB), a communication interface framework between hardware nodes and software applications. SDB provides a common interface method on both sides which enables seamless access of data from RTUs which can easily be integrated with the local HMI and other asset management applications. It can be scaled up for a number of hardware nodes and data points without sacrificing much of performance. [ABSTRACT FROM AUTHOR]

Bismuth layered structure ferroelectric materials of Aurivillius family have been attracted on account of their inherent-ferroelectric properties. Rare earth modified two layered compound, namely, Bi3TiNbO9has been found to be a relaxor ferroelectric material, and therefore much attention is being concentrated to enhance the dielectric properties with different modifications. In view of this, Sm-modified novel ceramic(Bi2SmTiNbO9) was prepared by the conventional solid-state reaction method. Impedance spectroscopic measurements were made as a function of frequency at different temperatures. Electrical studies were also made, and the results were corroborated to the Raman spectroscopic data. [ABSTRACT FROM AUTHOR]

Bismuth titanate (BT-‘Bi4Ti3O12’) is one of the extensively studied materials of the Bismuth layered structure ferroelectric (BLSF) family for its large spontaneous polarization along c-axis. In the present investigation, we have synthesised SmxBi4-xTi3O12(x = 0.37, 0.57, 0.72) ceramics using the conventional solid-state reaction method. The dielectric anomaly was observed near 450°C. Well-broad hysteresis loops were observed above room temperature up to 100°C. The coercive field (Ec) and consistent remanent polarization (Pr) values with temperature, compared to BT, indicates that the title compound has good promising ferroelectric-nature. This phenomenon is attributed to the easy recovery of defects (such as oxygen vacancies) accumulated at grain-interfaces, above room temperature, resulting in to well-hysteresis behaviour. The results were further confirmed with remanent polarization (2 Pr vs. temperature) plots. [ABSTRACT FROM AUTHOR]

Single-phase bismuth layered structure ferroelectromagnet (BLSFEM) LaGdxB5-xFe2Ti3O18of composition (x = 0.1, 0.2, 0.4, 0.6 and 0.8), novel ceramics were prepared by solid state route. Electrical and impedance measurements were made on the ceramics. Complex Impedance spectroscopic plots showed the signature of magnetic ion (Gd) and the results were corroborated to the Debye and Gaussian fitting curves. The variation of dielectric and modulus with temperature plots were used to explain dielectric phenomenon. An attempt is made to understand the effect of magnetic (Gd) ion on A site of (Bi2O2)2+(LaGdxBi3-xTi3Fe2O16)2−, layered perovskite (title) compound. [ABSTRACT FROM AUTHOR]

Depleting water resources and increasing human demands on the available fresh water resources suggest the need and scope for integrated water resources assessment and management. Narava basin, a small watershed spread over 105 km² with a khondalitic suite of rocks and gneisses of Archaean age in the north coastal region of Andhra Pradesh, India was studied to propose effective water resources assessment and management strategies. The watershed, with an undulating topography and gentle to steep slopes, is drained by a dendritic to sub-dendritic drainage system. The watershed receives an annual average rainfall of 980 mm. With increasing agricultural activity, monsoon failures, and indiscriminate developmental activities, groundwater during the last two decades has become the main trusted source for irrigation and drinking. A hydrogeomorphological approach integrating remote sensing applications, geoelectrical investigations and hydrological studies was proposed to delineate and study the groundwater potential and recharge dynamics in the Narava watershed. Linking the remote sensing data, morphometric characteristics, topographic analysis, land use/cover assessment and groundwater conditions, hydrogeomorphic maps were prepared. Synergizing the lineament densities with layer parameters, aquifer yields, groundwater occurrence and dynamics, groundwater potential zones were demarcated and classified. Merging the characteristics of groundwater potential, hydrogeomorphology and water balance, suitable water harvesting structures and management strategies are suggested. [ABSTRACT FROM AUTHOR]

The bismuth layer structured ferroelectric (BLSF) ceramics consisting of four-layers (BaLa0.75Bi3.25Ti4O15) and five-layers (Ba2La0.75Bi3.25Ti5O18) were prepared by the conventional solid-state reaction method. Summerfield ac-conductivity scaling analysis was used to evaluate the electrical behavior and the ac-conductivity isotherm curves. The relaxation results were corroborated with the Raman Peak positions and full width at half maximum was obtained by using Lorentzian peak fit method. Finally, the results were compared with the two-layered relaxor-compound (Bi2.45La0.55TiNbO9) and technologically standard three-layered compounds (La0.75Bi3.25Ti3O12; BLT). The dielectric relaxation of Bi2.45La0.55TiNbO9was verified using modified Curie-Weiss law and Vögel-Fulcher relationship. An attempt is made to realize the typical collective nature of the ionic conductivity of the samples. [ABSTRACT FROM AUTHOR]

A laboratory bioassay was conducted to study the impact of Cry 1 Ac protein on survival and development of Helicoverpa armigera (Hubner.) by feeding larvae with Bt cotton plant parts. During the study, terminal leaves and squares of two Bt hybrids, their corresponding non Bt hybrids and Bunny as check were fed to larvae. Among the plant parts tested, mortality of H.armigera larvae was higher on leaves compared to squares of both the Bt hybrids. Further, the mortality of early larval instars was higher compared to older instar larvae on both leaves and squares of Bt hybrids. Though, the later instar larvae were able to survive when exposed continuously to Bt cotton plant parts, but reduction larval and pupal weight, increase in larval developmental period, malformations in pupae and adults, reduction in adult emergence, less fecundity, low growth and survival indices was observed on both the Bt hybrids compared to their corresponding non Bt hybrids and check hybrid, Bunny. [ABSTRACT FROM AUTHOR]