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Because of their high stability, innocuous behaviour, outstanding electric properties and multi-functionality, lead-free double perovskites have emerged as a promising alternative to lead-based perovskites. We present here the structural, microstructural, dielectric and electrical properties of a newly synthesized double perovskite Nd2FeTiO6 (NFTO). The Rietveld refinement of its X-ray diffraction pattern revealed a monoclinic structure with space group P121/c1. The oxide exhibits a temperature-independent dielectric constant and di-electric loss at low temperatures (below 200 °C) making the compound a suitable candidate for fabricating thermally stable capacitors. The AC conductivity was investigated using the Jonscher’s universal power law, and it was inferred that the conduction process is caused by the Correlated BarrierHopping (CBH) mechanism. Furthermore, frequency dependent AC conductivity also revealed the NTCR nature of the NFTO compound.

This study aims to investigate the non-linear free vibration behavior of composite sandwich panels composed of Graphene-reinforced composite (GRC) skins and honeycomb auxetic core. Here, modified Halpin-Tsai micromechanics and bottom-up multi-scale-based schemes are employed to compute the spatial-dependent elastic properties of Graphene nanocomposite and auxetic honeycomb core, respectively. The non-linear kinematic field is based on Kant's higher-order shear-deformation theory and the Green strain. Using the Hamilton principle, the nonlinear governing equations are affirmed and solved further through Picard's iteration-based 2D-isoparametric finite element approximations via Lagrangian elements. The mesh convergence and validation tests are executed to confirm the consistency and correctness of the developed model. The established sandwich model is further employed for various parametric conditions by varying the core-to-face sheet thickness, auxetic honeycomb properties, graphene volume fraction, shell configurations, temperature, and support conditions. These numerous results exemplify the non-linear frequencies at small-to-large amplitudes for the sandwich shell structures and are discussed in detail. In addition, parametric optimization is conducted using the response surface method to investigate the optimal values of auxetic honeycomb parameters, resulting in maximum frequency response. Findings confirm that, within the selected ranges of the geometric parameters of auxetic honeycomb core, higher values of the thickness of the cell rib (∼1.9 cm) and the length of the vertical cell rib (∼0.15 cm) and lower value of the core thickness (∼5 cm) yield the maximum frequency. [ABSTRACT FROM AUTHOR]

In this article, the non‐linear free vibration behavior of sandwich composite panels with sinusoidal corrugations is examined. These panels consist of a top and bottom skin made of a graphene‐reinforced composite, with an auxetic honeycomb core having negative Poisson's ratio. The non‐linear kinematic field is based on Kant's higher‐order shear‐deformation theory and the Green‐strain, which incorporates all the higher‐order terms. By implementing the Hamilton principle, the non‐linear governing equations are affirmed and solved further through 2D‐isoparametric finite element approximations via Lagrangian elements in conjunction with Picard's successive iterative scheme. The comparison and validation tests demonstrate the correctness of the present model. The established sandwich model is further employed for various parametric conditions by varying the core‐to‐face sheet thickness, auxetic honeycomb properties, graphene volume fraction, shell configurations, temperature, and support conditions. These numerous results exemplify the non‐linear frequencies at small‐to‐large amplitudes for the sandwich shell structures and are discussed in detail. In addition, a multi‐objective parametric optimization is conducted using the response surface method to investigate the optimal values of the corrugated auxetic honeycomb shell panel's parameters, resulting maximum frequency. Highlights: Non‐linear vibration of corrugated sandwich shell panel.Graphene reinforced skins and honeycomb auxetic core.Kant's higher‐order shear‐deformation theory and Green‐Lagrange non‐linearity.Hamilton principle and Picard's successive iterative scheme.Multi‐objective parametric optimization and prediction using response surface methodology. [ABSTRACT FROM AUTHOR]

Adansonia digitata L. (Malvaceae) is commonly known as baobab tree native to Africa. Baobab is a multi-purpose tree which offers protection and provides food, clothing and medicine as well as raw material for many useful items. The fruit pulp, seeds, leaves, flowers, roots, and bark of baobab are edible and they have been studied by scientists for their useful properties. The fruit pulp have very high vitamin C, calcium, phosphorus, carbohydrates, fibers, potassium, proteins and lipids content, which can be used in seasoning as an appetizer and also make juices. Seeds contain appreciable quantities of phosphorus, magnesium, zinc, sodium, iron, manganese, whereas they have high levels of lysine, thiamine, calcium and iron. Baobab has numerous biological properties including antimicrobial, anti-malarial, diarrhoea, anaemia, asthma, antiviral, anti-oxidant and anti-inflammatory activities amongst others. Phytochemical investigation revealed the presence of flavonoids, phytosterols, amino acids, fatty acids, vitamins and minerals. The review summarizes the information on various aspects of traditional information, taxonomic description, medicinal properties and importantly nutritional value.

Wireless applications require compact antennas capable of operating over a wide range of frequencies with minimal power. Microstrip patch antennas are generally preferred for transceivers that operating at microwave frequencies due to their low profile and easy installation. The performance of antennas has been evaluated using the metrics collected from of return loss, Voltage Standing Wave Ratio (VSWR) and radiation pattern. The overall size of the antenna has dimensions of 34 mm × 28 mm × 1.6 mm, fabricated on FR4 substrate having relative permittivity of 4.4. The proposed antenna achieves maximum return loss of -21.30 dB at 2.9 GHz, -23.51 dB at 5.3 GHz and -19.17 dB at 10 GHz. [ABSTRACT FROM AUTHOR]

The provisions of section 3(d) of the Indian Patent Act, 1970, were designed to promote and protect the manufacturing of low cost generic medicines in the country. Along with other changes and amendments, they were assumed to benefit the states equally without taking into account the inter-state economic inequalities. The provisions were set forth to secure production of inexpensive generic drugs for easy accessibility at affordable prices across the states. The paper assumes states whose per capita net state domestic product is lower than the per capita net national product, and thus do not get full benefit of inexpensive generic drugs. The section patronises domestic generic drug manufacturers and users from coercive provisions of Trade Related Aspects of Intellectual Property Rights Agreement and foreign patent holder's aggressive monopoly price. However, it does not guarantee the availability of price effective generic drugs for the people of backward states. Hence, some states need additional attention to make the generic drugs affordable and accessible. The paper has investigated into the intra-molecular price variation of generic drugs and its impact on their affordability in backward states. It aims to find out whether all Indian states equally benefit from the IP Act, or some states are unable to reap its benefit because of the lack of proper policy measures. The analysis is based on both descriptive and analytical methods. It has applied ratio analysis with the data on per capita net state domestic product (proxy of the purchasing capacity) of selected backward states with price data of generic drugs prescribed for major death-causing diseases. [ABSTRACT FROM AUTHOR]