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Electromagnetic radiation (EMR) pollution is a serious concern in today's environment, causing problems not just for electronic gadgets but also for living society. The goal of this research is to fabricate thermoplastic polyurethane (TPU) and polypyrrole (PPy)-based 95:5 blend nanocomposites using a simple solvent casting method at such a low concentration of rGO and MWCNT (0.3, 0.4, 0.5 php) (parts per hundred polymers), for electromagnetic wave (EMW) absorption applications. The chemical interaction between the different phases and morphology of the nanocomposites is characterized by Raman spectroscopy, X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) techniques. The material properties, such as dielectric and magnetic properties, are analyzed in X-band frequency (8.2-12.4 GHz). The total shielding effectiveness of (SETot) 0.5 rGO system is found to be 27 dB, whereas, for corresponding MWCNT nanocomposites, it is 26 dB. Interestingly, in 0.5 rGO nanocomposites, absorption shielding effectiveness (SEAbs) is approximately 25 dB, and reflection shielding effectiveness (SERef) is less than 2 dB, which indicates the absorption of 70% of the electromagnetic wave, and the rest gets reflected. Apart from that, the rGO-based nanocomposites possess a greater extent of thermal stability than the corresponding MWCNT-based nanocomposites. Highlights • Fabrication of TPU-PPy-rGO and TPU-PPy-MWCNT nanocomposites by solvent casting. • Low reflection of TPU-PPy-rGO nanocomposites with a 70% absorption rate. • FESEM confirms the multilayer interface structures. • Tunable Dielectric and magnetic properties of nanocomposites in X-band. • Excellent absorption dominant properties of the fabricated nanocomposites. [ABSTRACT FROM AUTHOR]

Recently, ceramic patch antennas have been intensively researched for mobile communication systems. This work shows the unique use of Bi0.5Na0.5TiO3 (BNT) ceramic in microstrip patch antenna substrates for 8–12 GHz operation. The synthesized ferroelectric perovskite-based substrate of thickness t = 1.02 mm was utilized to produce the simulated antenna. The relevant electromagnetic parameters of permittivity, permeability, dielectric loss, magnetic loss, and miniaturization factor were studied. Characterization procedures are used to analyze the synthesized sample's crystal structure, local vibration, surface morphology, and elemental analysis. The rectangular-based split ring microstrip patch antenna's reflection loss, return loss, and radiation pattern were calculated using CST Microwave Studio v. 2019. The best yield result of simulation is − 55 dB which corresponds to the fabricated result of about − 25 dB for substrate thickness of t = 1.02 mm. The uniqueness of the synthesized sample has been modified parametrically by modifying its thickness for t = 0.9 mm, t = 1 mm, and t = 1.02 mm among which t = 1.02 mm thickness of the substrate is optimal for optimum results. [ABSTRACT FROM AUTHOR]

An echocardiographic investigation is one of the key modalities of diagnosis in patients suffering from COVID 19, especially if they are elderly, have associated comorbid conditions, and pregnant. Hence, it is becoming extremely essential to look into the correct safety precautions, health-care professionals must take while conducting an echo investigation. At the same time, a focused echo examination aimed at correct imaging view acquisition in the shortest possible time is the need of the hour. The decision matrix formulated for conducting an echocardiographic evaluation is based on the presence or absence of cardiological comorbidity vis-a-vis positive or suspected for COVID- 19. The safety measures and image acquisition have been constructed keeping in mind the current safety precautions by the World Health Organization, the Centers for Disease Control and Prevention, and the Ministry of Health and Family Welfare, India. [ABSTRACT FROM AUTHOR]

The nanocrystalline Pb0.92Nd0.08(Zr0.53Ti0.47)0.98O3 (PNZT) has been synthesized by high-energy ball milling (mechanical alloying). X-ray diffraction studies shows that these compounds are tetragonal. Detailed studies of impedance and dielectric properties of PNZT as a function of temperature (and frequency) showed the high permittivity of 10 626 at 10 kHz at the Curie temperature (TC), broadening of permittivity peak, lowering of TC, decrease in conductivity, and increase in relaxation time with the decrease in crystallite size. [ABSTRACT FROM AUTHOR]

The nanocrystalline Gd-doped lead titanium zirconate (PGZT) with the composition Pb[sub 0.92]Gd[sub 0.08](Zr[sub 0.53]Ti[sub 0.47])[sub 0.98]O[sub 3] has been synthesized by a combination of high-energy ball milling [mechanical alloying (MA)] and sintering. PGZT prepared by MA followed by high-temperature sintering has a higher dielectric constant compared to that of the conventional technique. PGZT shows a nonrelaxor ferroelectric behavior but has diffuse ferroelectric–paraelectric phase transition. The activation energy of the material was found sensitive to its crystallite size. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]