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The strontium-modified barium titanate ( Ba 0. 7 Sr 0. 3 TiO 3) ceramic was fabricated by high temperature compound reaction route. The pattern of X-ray diffraction confirms a single-phase compound with better crystallization. The dielectric properties (permittivity/loss) are investigated as a function of temperature and frequency. The relaxation mechanism and correlation with the physical properties are studied using complex impedance spectroscopy. The Nyquist plot shows the association of various effects (grain and grain boundary) by fitting electrical circuits at various temperature regions. This study tells the nature and conduction mechanism of the prepared sample. The Jonscher's universal power law is being followed by the frequency-dependent ac conductivity. [ABSTRACT FROM AUTHOR]

Relaxation mechanism, conductivity and magnetoelectric properties of (Nd1/2Li1/2)(Fe2/3Mo1/3)O3 multiferroic have been investigated systematically. This material was synthesized by a solid-state reaction route. Thermogravimetric analysis is enforced to perceive the percentage of weight change with rise in temperature in order to obtain the calcination temperature of the material. The preliminary structural study using X-ray diffraction data reveals the orthorhombic structure of the material. The complex plot of impedance data helped to distinguish the involvement of grain as well as grain boundary effects towards the overall electrical properties of the compound. Temperature-dependent electrical conductivity plots exhibit the presence of thermally activated conduction mechanism of the compound. The magnetic field dependence of magnetization (M–H loop) showed the presence of ferromagnetic nature of the material. The value of magnetoelectric coupling coefficient of prepared material is found to be 2.7 mV Cm−1 Oe−1. [ABSTRACT FROM AUTHOR]

In the present communication, studies of some physical properties (i.e., crystal data, permittivity, impedance, electrical cobnduction and magnetic) of a multiferroic material with a chemical composition (SmLi)1/2(Fe2/3Mo1/3)O3 have been reported. Thermogravimetric analysis of the compound, prepared by cost effective ceramic technology processing, was executed to check the mass loss as well as the required decomposition temperature of the ingredients. An analysis of X-ray spectra or pattern suggests that the crystallization phase or cystal system of the compound at room temperature is orthorhombic. The broad studies of dielectric properties {relative dielectric constant (εr), and tangent loss (tan δ)} display their independence of temperature and frequency in the rage of (30-375 °C) and (1 kHz-1 MHz) respectively. The impedance spectroscopic technique has provided a considerable significant information regarding the grain, grain boundary contribution within the sample and relaxation mechanism of the compound. The occurrence of negative temperature coefficient behaviour (NTCR) is depicted by the further analysis of impedance parameters. The frequency-temperature dependence of conductivity follows the Johnson’s power Universal law. The Arrhenius plot (i.e., variation of electrical conductivity with temperature) is used to calculate the activation energy. Analysis of magnetization (M-H) loop shows weak ferromagnetism of the compound. The material possesses significantly high magnitude of magnetoelectric coefficient of 3.0 mV Cm− 1 Oe− 1. [ABSTRACT FROM AUTHOR]

A single phase multiferroic magnetoelectric compound, (Sm 0.5 Li 0.5 )(Fe 0.5 V 0.5 )O 3 , is found at room temperature. This sample is fabricated using solid state reaction route. Analysis of the structural properties of the sample by X-ray diffraction method confirmed the fabrication of the desired compound with orthorhombic unit cell structure. Morphological property of the sample is recorded by field emission scanning electron microscopy (FE-SEM). Impedance spectroscopy is employed to determine the various electrical parameters such as dielectric constant, loss tangent, impedance, electric modulus, etc. at different temperature (RT–400 °C) within a frequency range of (1 kHz–1 MHz). Furthermore, the bulk resistance as function of temperature and J – E characteristic showed the semiconducting behavior of sample with negative temperature coefficient of resistance (NTCR) type nature of the compound. The M – H loop of this sample indicates the ferromagnetic nature with very low coercive field. A dedicated magnetoelectric set up is used to measure the ME coefficient as a function of magnetic field and found a significant ME coefficient of 2.99 mV Cm −1  Oe −1 at room temperature. [ABSTRACT FROM AUTHOR]

Scorpion sting is a public health concern with limited clinical symptomatic treatment. The clinical treatment uses anti-scorpion antivenom and prazosin (α-adrenergic inhibitor), often in combination with insulin, to reduce scorpion venom-induced hyperglycemia and other complications. However, these therapies also possess some limitations, necessitating urgent exploration of ethnomedicines, mainly traditional medicinal plants, to treat scorpion stings. Unfortunately, several conventional treatments are not scientifically validated, thus raising questions about their quality and utility. Therefore, pharmacological re-assessment of such medicinal plants to alleviate scorpion stings' complications is essential. The principal objectives of this study are to provide a brief overview of medically important scorpions of the world, outline the extant traditional practices, and comprehensively review plants used in conventional ethnic medicines to treat scorpion stings over time. Modern technological advances in identifying and characterizing plant bioactive molecules are also mentioned in this review. The traditionally used medicinal plants against scorpion stings were reviewed from the available literature in the database. The Plant List (http://www.theplantlist.org/) was used to validate the scientific names of the plants mentioned in this study. The search targeted literature on conventional treatments and crude plant extracts or their bioactive components with proven neutralization capacity against scorpion stings. Search words used were 'scorpion sting,' 'treatment for a scorpion sting,' 'antivenom and scorpion sting,' 'traditional treatment for scorpion stings, and 'natural compounds against scorpion stings'. A list of more than 200 medicinal plants traditionally used in several countries for treating scorpion stings is presented in this review. Though some myth-based remedies are practiced to treat scorpion stings, no empirical evidence exists to validate this aspect of traditional knowledge. Only 38 traditional medicinal plant extracts have been tested under in-vivo and in-vitro conditions to determine their neutralization potency of scorpion envenomation. Although a few bioactive plant constituents showing scorpion venom neutralization potency have been characterized, they are not yet commercially available for clinical application. There is tremendous potential locked in medicinal plants' traditional knowledge for scorpion envenomation treatment. Translating this knowledge into the clinical application will require pharmacological reassessment, in tandem with isolation and characterization of active compounds to prove their prophylactic prowess. Almost equally important would be the formulation of stringent strategies to conserve such medicinal plants from overexploitation. [Display omitted] • Key issues associated with the traditional methods of treatment for scorpion stings are mentioned. • Traditionally used medicinal plants for the treatment of scorpion stings are listed. • Medicinal plants tested for anti-scorpion activity have been analyzed and critically reviewed. • Strategies for commercialization of bioactive compounds for treating scorpion stings are discussed. [ABSTRACT FROM AUTHOR]

Using high-temperature solid state reaction technique a new polycrystalline multiferroic material of (LaLi)(FeMo)O has been prepared. Thermo-gravimetric analysis is carried out to optimize the calcination temperature of the material. The formation of the desired compound is confirmed by preliminary X-ray diffraction analysis. The complex impedance spectroscopy technique is used to study the dielectric properties and other electrical parameters (loss tangent, impedance, modulus, conductivity) of the material as a function of frequency (1 kHz-1 MHz) at different temperatures (RT−425 °C). The nature of Nyquist plot confirmed the presence of bulk and grain boundary effect in the compound. The relaxation time obtained from the maximum frequencies corresponding to the imaginary impedance and electric modulus plots at different temperatures are found to obey Arrhenius law. The temperature and frequency dependence of ac conductivity plot obeys Jonscher's universal power law. The P-E loop confirms the ferroelectric behavior of the compound at room temperature. [ABSTRACT FROM AUTHOR]

In this study we have synthesized lead-free polycrystalline sample of (LaLi)(FeV)O multiferroic by a standard high-temperature solid-state reaction technique. TGA has been carried out to observe the weight loss of the material with rise in temperature. The formation of the material has been confirmed by preliminary structural analysis using X-ray diffraction data. The dielectric permittivity (constant), loss tangent, impedance, and electric modulus of silver coated pellet sample were measured in a wide frequency range (1 kHz-1 MHz) at different temperatures (30-375 °C). The Nyquist plots show the contributions of grain and grain boundary effect in the impedance characteristics of the material. The bulk resistance calculated from the impedance data decreases with increase in temperature showing negative temperature coefficient of resistance (NTCR)-type behaviour of the material. The frequency dependence of ac conductivity at different temperature indicates that the material obeys Jonscher's universal power law. The nature of variation of dc conductivity follows Arrhenius law. Detailed studies of modulus spectrum suggest that the material exhibits non-Debye type of relaxation mechanism, which is consistent with the impedance data. The room temperature magnetic (M-H) and ferroelectric (P-E) loops confirm the ferromagnetic and ferroelectric ordering present in the prepared material. [ABSTRACT FROM AUTHOR]