The current work investigated two ionic-liquid (IL)-based deep eutectic solvents (DESs) composed of ethylene glycol (EG) and N-methylacetamide (NMAc) as hydrogen bond donors (HBD) and high-melting IL, namely, 1-butyl-3-methylimidazolium methanesulfonate ([BMIM]-[MeSO 3 ]), as the hydrogen bond acceptor (HBA). Initially, the COSMO-SAC model was employed for prediction of the eutectic points of the DESs. The computed melting points of the formulated DESs were found to be 70−100 °C lower than that of HBA. The viscosity of the newly developed DESs (∼15 cp) was significantly lower than that of neat room temperature IL electrolytes, and their ionic conductivity was found to be comparable to that of ILs. TGA study revealed no mass loss up to 90 °C, favoring the high temperature application of supercapacitors. To assess electrolytic performance in supercapacitors, electrochemical characterization was done using linear scan voltammetry (LSV), cyclic voltammetry (CV), and galvanostatic charge−discharge (GCD) techniques. LSV provided electrochemical stability up to 3.8 V against a glassy carbon electrode.[BMIM][MeSO 3 ] + EG and [BMIM][MeSO 3 ] + NMAc resulted in operating potential windows (OPWs) of 2 and 3 V, respectively, with a carbon electrode. Moderate values of specific capacitance (55−67 F g −1 ) and power (0.56−1.3 kW kg −1 ) were observed due to higher internal resistance. However, [BMIM][MeSO 3 ] + NMAc resulted in noteworthy specific energy (∼84 Wh kg −1 ) due to its wider OPW.

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A tricritical point is observed in the Nd1−xSrxMnO3 (NSMO) (x=0.3, 0.33, and 0.4) manganites at x=0.33 which separates the first-order transition in NSMO-0.3 and second order transition in NSMO-0.4. The ferromagnetic transition of these compounds is further investigated by measuring magnetocaloric effect (MCE) and by applying a theoretical model based on Landau theory of phase transitions. Results indicate that the contributions to the free energy from the presence of correlated clusters are strongly influencing the MCE by coupling with the order parameter around the Curie temperature.

An ex situ electrochemical impedance spectroscopy (EIS) method is used to evaluate the effectiveness of tetramethyl ammonium hydroxide (TMAH) in removing benzotriazole (BTA) layer from Cu surface after chemical mechanical polishing (CMP). Since the in situ EIS measurements could not be applied to characterize the cleaning process, ex situ EIS measurement is used in the present work. The impedance data are modeled by electrical equivalent circuit (EEC) analysis and the polarization resistance values are calculated. The BTA removal for various concentrations of TMAH is quantified from polarization resistance values. Scanning electron microscopy and X-ray photoelectron spectroscopy measurements were also conducted to complement the studies. The results show TMAH is effective in removing the BTA layer and that when part of the BTA is removed, the residual BTA appears as nodules. Some of the native oxides and hydroxides on the Cu surface are also removed by TMAH. When the slurry contains 0.1% (wt) BTA, a minimum concentration of 0.5% (wt) TMAH and a minimum cleaning time of 60 s are required for complete removal of BTA from the Cu surface. The suggested ex situ EIS technique is sensitive in evaluating removal efficiency of the organic contaminant from the metallic surface.

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The V-Ti alloys are promising materials as alternate to the commercial Nb-based superconductors for high currenthigh magnetic field applications. However, the critical current density (Jc) of these alloys are somewhat low due to their low grainboundary density. We show here that grain refinement of the V-Ti alloys and enhancement of the Jc can be achieved by the addition of Gd into the system, which precipitates as clusters along the grain boundaries. Both the Jc and the pinning force density ( ) increase with the increasing Gd content up to 1 At. % Gd, where they are more than 20 times higher than those of the parent V0.60Ti0.40 alloy. Introduction of Gd into the system also leads to ferromagnetic (FM) correlations, and the alloys containing more than 0.5 At. % Gd exhibit spontaneous magnetization. In spite of the FM correlations, the superconducting transition temperature increases slightly with Gd-addition.