Sarkar, Abhishek

This study primarily focused on forming pure single-phase FeSb and explored its thermoelectric, mechanical, and electrochemical properties since no reports are available. The FeSb binary alloy has been synthesized through the vacuum melting method, and the phase formation has been confirmed through powder X-ray diffraction (PXRD). The PXRD results show that the synthesized FeSb binary alloy belongs to the hexagonal crystal structure with space group P63/mmc, which coincides with ICSD no. 53971. The pure single phase has been formed by creating a deficiency of 10 % in antimony. The High-Resolution Scanning Electron Microscopy (HR-SEM) and Energy Dispersive X-ray (EDX) analysis have been used to identify the pure single-phase and various elemental components of the hot-pressed pellet of FeSb0.9. The atomic wt.% of iron (Fe) and antimony (Sb) have been identified through EDX spectral analysis. The highest Seebeck coefficient value of −5.4 μV/K is achieved at 497 K, and the lowest electrical conductivity value of 24049 S/m is achieved at 447 K. The hardness of the material is found to be 6.076 GPa, which is much more sufficient for thermoelectric material during industrial handling. The magnetic characteristics of the prepared pure phase FeSb compound have also been measured by Vibrating Scanning Magnetometer (VSM) analysis, which has a weak ferromagnetic nature. Furthermore, three electrodes were employed to study the electrochemical properties, and the alloy has attained the appreciable specific capacitance of 169.5 F/g at 2 A/g.

In this paper, we deal with the existence of nontrivial nonnegative solutions for a (p, N)-Laplacian Schrödinger–Kirchhoff problem in ℝN with singular exponential nonlinearity. The main features of the paper are the (p, N) growth of the elliptic operators, the double lack of compactness, and the fact that the Kirchhoff function is of degenerate type. To establish the existence results, we use the mountain pass theorem, the Ekeland variational principle, the singular Trudinger–Moser inequality, and a completely new Brézis–Lieb-type lemma for singular exponential nonlinearity.

For N≥ 5 and α > 0, we consider the following semipositone Problem ( equation presented) where g ϵ L1 loc(RN) is an indefinite weight function, fα : R → R is a continuous function that satisfies fα(t) = -α for t ϵ R-, and D2,2(RN) is the completion of C∞ c (RN) with respect to ( ∫ RN (Δu)2)1/2. For fα satisfying subcritical nonlinearity and a weaker Ambrosetti-Rabinowitz type growth condition, we find the existence of α1 > 0 such that for each α ϵ (0, α1), (SP) admits a mountain pass solution. Further, we show that the mountain pass solution is positive if α is near zero. For the positivity, we derive uniform regularity estimates of the solutions of (SP) for certain ranges in (0, α1), relying on the Riesz potential of the biharmonic operator.

The purpose of this paper is to present the model of a Humanoid robot inspired by Poppy, modified for heavier load capacity and the balancing of humanoid in multiple work environments. The design has been modified in order to use MX-64 servos with more torque capacity than MX-28 servos which were used in original design. We have also redesigned the ankle joint and feet to make it a more accurate human like model. We are using an integrated approach using zero moment point (ZMP) with force sensing resistor (FSR) and center of mass (CoM) to find balance margins of the robot. Balancing and forward bending experiments on robot are conducted by providing some basic motion to the robot and ensuring that the robot is balanced and moving within safe margins using this approach.

Aqueous Zn batteries, which use metallic Zn as anodes, have gained significant attention due to their affordability and high safety standards. However, these Zn anodes are plagued by issues such as Zn dendritic growth and side reactions, including corrosion and hydrogen evolution. One straightforward yet effective approach to mitigate these issues is to apply protective coatings to the Zn anodes to enhance their reversibility. It is generally believed that these protective layers should have a high affinity for Zn. Contrarily, this study proposes that non-conductive coatings should form a strong binding with H+ ions while maintaining a weaker interaction with Zn2+ ions, thereby ensuring a higher selectivity for H+ over Zn2+. This concept is illustrated using zirconium dioxide (ZrO2), an ionic conductor that meets these criteria and effectively curbs side reactions and dendritic growth of Zn. Remarkably, Zn anodes coated with ZrO2 layer demonstrate a lifespan exceeding 6000 h at 1 mA cm−2 and 1 mAh cm−2, significantly outperforming uncoated ones, which last <200 h. This discovery introduces a novel design principle for insulating surface coatings, potentially applicable not only for Zn but also for other metal anodes.