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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]

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]

Copyright of Nanosistemi, Nanomateriali, Nanotehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

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]

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]

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]

This paper will engage with the concept of a 'technology synergy eco-system' which blends together the two core elements of HD video DSLR and the new social media platform to determine, if this could actually be a potent formula for the emergence of a potential alternative virtual cinema. This alternative virtual cinema has both connotations as a medium of transmission of a certain film to the masses and also elements of film techniques in terms of aesthetics and etc. It is beyond a shadow of a doubt that in this current day and age, we can see that the social new media has impacted practically every facet of society. The question beckons then, what about cinema? Does the level of interactivity in which the social new media provides, combined with the affordability and ease of using a HD video DSLR to produce videos with high production values and cinematic quality nuances serve as a precursor to the trends and patterns which might lead up to an alternative virtual cinema? With these exciting questions in mind, it is of great interest to us as modern day filmmakers, in exploring and giving an exposition into this subject matter, to deconstruct the elements and see if the possibility is viable or merely an idealistic notion. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Research, Engineering & Management / Aplinkos Tyrimai, Inžinerija ir Vadyba is the property of Institute of Environmental Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Plant Protection Research is the property of Institute of Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A field experiment was conducted to evaluate the efficacy of certain new molecules as well as entomopathogens as foliar sprays against leafhoppers in Bt cotton at Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh for two consecutive years. The new molecule, flonicamid 50% WG at two doses i.e. at 75 g a.i./ha and 100 g a.i./ha followed by diafenthiuron 50% WP 300 g a.i./ha and buprofezin 25% SC @ 250 g a.i./ha were found promising against leaf hoppers together with high seed cotton yield. New molecules were found significantly superior over to NSKE 5 % and entomopathogens in suppressing the leafhoppers. [ABSTRACT FROM AUTHOR]

Objectives: Hyperlipidemia constitutes a major etiopathological factor for atherosclerosis. The medicinal value of garlic is best known for its lipid lowering effects and antiatherogenic effects. The mechanism by which lipid soluble organosulphur compounds from garlic reduce plasma lipids has not been fully investigated. The author had previously shown that the hepatic activity of beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA) reductase, the rate limiting enzyme in cholesterol biosynthesis and the incorporation of radiolabeled (1, 2 14C), acetate into hepatic free and esterified cholesterol was significantly decreased in rat treated with garlic derived organosulphur compounds. We hypothesised that the antiatherogenic effect of the organosulphur compounds may be attributed to the formation of protein internal disulphide and thus inactivation of thiol (-SH) group enzymes such as HMG-CoA reductase and the multienzyme complex of fatty acid synthesis. The objective of the present study is to elucidate the inhibitory mechanism by in vitro studies., Method: Lipid soluble organosulphur compounds from garlic were treated in vitro with Luke's cysteine reagent (representing the thiol (-SH) group of enzymes) and the interaction products were separated by paper chromatography., Result: The result indicated that the organosulphur compounds were capable of interacting with the thiol (-SH) group of cysteine and thus forming cysteine derivatives., Conclusion: The antiatherogenic effects of these organosulphur compounds can be attributed to such reactions that inhibit HMG-CoA reductase and other lipogenic enzymes. The anticarcinogenic effects of these compounds may also be due to inhibitory reactions on enzymes that activate carcinogens.