We report on the superconducting state of Ti 0.8 V 0.2 alloy, highlighting an anomalous magnetic response in the flux-line lattice or the mixed state. The value of magnetization while cooling down the alloy in the presence of high magnetic field is lower than that obtained while warming it up from the lowest temperature in the presence of the same magnetic field. This is just the opposite to the thermo-magnetic hysteresis observed due to homogeneous flux-line pinning. This anomalous effect appears below a characteristic temperature that shifts towards a lower temperature with the increase in applied magnetic field. The value of magnetization measured at a constant temperature after cooling down the sample in the presence of magnetic field increases appreciably with time in the temperature-field domain where this anomalous effect is observed. These results indicate that the present Ti 0.8 V 0.2 alloy exhibits a high field paramagnetic effect resulting from inhomogeneous flux pinning. Optical metallography and x-ray diffraction measurements show the formation of stress induced martensitic phase in the alloy, which could result in the inhomogeneous flux pinning. The temperature dependence of magnetization after annealing the sample after mechanical processing showed the usual properties of a type-II superconductor. This supports the argument that the inhomogeneous distribution of the stress induced martensitic phase is the reason for the existence of the high field paramagnetic effect in Ti 0.8 V 0.2 alloy.

and pursued her research for 4 years. Afterwards, she joined as Research Assistant in DST funded project at Centre for Advanced Studies, Dr APJ AKTU, Lucknow in 2019.Her Research Interest mainly focuses on designing of micro-and nano-devices, microand nano-structured materials for various sensors and energy storage devices. Tata Narasinga Rao received his Ph.D. degree in Chemistry from Banaras Hindu University, India in 1994. After working at IIT Madras as Research Associate, he moved to the University of Tokyo in 1996 as a JSPS post-doctoral fellow and subsequently became lecturer in the same university in 2001. He joined International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India, in 2003 as senior scientist, and presently he is Scientist G and Associate Director of ARCI. His primary research area includes development of Li-/Na-ion battery, Li-S battery, supercapacitors. He is presently working on nano-coated self-disinfecting masks and antiviral-paints.

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In material sciences, synergistic effect and nanostructuring are the two factors which enable researchers to look beyond the conventionally defined categories of the materials. Here, we report the synthesis mechanism of pure phase mesoporous Li 2 MnSiO 4 (LMS) with a high specific surface area by varying the concentration of metal precursors and solvents in one-step hydrothermal technique. Furthermore, the effect of MWCNTs addition on the electrochemical performance of LMS is studied. The quantitative contribution of current generating from EDLC and/or the surface pseudocapacitance reactions, and the current caused by diffusion-controlled redox reactions in the total current is also evaluated. The pure phase LMS/CNTs nanocomposite with 2% MWCNTs (abbreviated as LMS2C) is found to be the best supercapacitor material among studied nanocomposites as it exhibits specific capacitance of ∼290 F g −1 @ 1 A g −1 , good rate capability, small relaxation time constant (τ = 87 ms), and higher diffusion coefficient of electrolytic cations (D k + = 9.4 × 10 −9 cm 2 s −1 ) in 2 M KOH aqueous electrolyte. A hybrid supercapacitor cell (HSC) designed using LMS2C as positive and activated carbon as negative electrodes shows the maximum energy density of 31 W h kg −1 , which is much higher than several recently reported hybrid supercapacitor systems. Two series connected HSCs can power a drone motor and light up 8 red LEDs for more than 3 min, indicating practical applicability of our designed hybrid supercapacitor system.

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Variable-temperature Raman spectroscopic and synchrotron X-ray diffraction studies were performed on BaTe2O6 (orthorhombic, space group: Cmcm), a mixed-valence tellurium compound with a layered structure, to understand structural stability and anharmonicity of phonons. The structural and vibrational studies indicate no phase transition in it over a wider range of temperature (20 to 853 K). The structure shows anisotropic expansion with coefficients of thermal expansion in the order αb ≫ αa > αc, which was attributed to the anisotropy in bonding and structure of BaTe2O6. Temperature evolution of Raman modes of BaTe2O6 indicated a smooth decreasing trend in mode frequencies with increasing temperature, while the full width at half-maximum (fwhm) of all modes systematically increases due to a rise in phonon scattering processes. With the use of our earlier reported isothermal mode Grüneisen parameters, thermal properties such as thermal expansion coefficient and molar specific heat are calculated. The pure anharmonic (explicit) and quasiharmonic (implicit) contribution to the total anharmonicity is delineated and compared. The temperature dependence of phonon mode frequencies and their fwhm values are analyzed by anharmonicity models, and the dominating anharmonic phonon scattering mechanism is concluded in BaTe2O6. In addition to the lattice modes, several external modes of TeOn (n = 5, 6) are found to be strongly anharmonic. The ab initio electronic structure calculations indicated BaTe2O6 is a direct band gap semiconductor with gap energy of ∼2.1 eV. Oxygen orbitals, namely, O-2p states in the valence band maximum and the sp-hybridized states in the conduction band minimum, are mainly involved in the electronic transitions. In addition a number of electronic transitions are predicted by the electronic structure calculations. Experimental photoluminescence results are adequately explained by the ab initio calculations. Further details of the structural and vibrational properties are explained in the manuscript.

In fully hydrated MCM-41 cylindrical pore, core water after freezing creeps out of pore forming a mixture of hexagonal and cubic ice. Water near the pore wall in both fully and partially filled pores forms short range cubic-rich ice after freezing.