We report a nonhalogenated surface-active ionic liquid (SAIL) that consists of the surface-active anion 2-ethylhexyl sulfate and the tetraoctylammonium cation ([N8,8,8,8]­[EHS]). We explored the thermal and electrochemical properties, i.e., degradation, melting and crystallization temperatures, ionic conductivity, and electrochemical potential window of neat SAIL and its binary mixture with acetonitrile. This SAIL was tested as an electrolyte in a multiwalled carbon nanotube (MWCNT)-based supercapacitor at various temperatures from 298 to 373 K. In addition, we also tested the binary mixture of SAIL with acetonitrile as an electrolyte at lower temperatures (253–298 K). The electrochemical performance of SAIL and the SAIL/acetonitrile binary mixture as a function of temperature was compared with that of a standard electrolyte, an aqueous solution of 6 M KOH, in the same MWCNT-based supercapacitor. The solution resistance (R s), charge transfer resistance (R ct), and equivalent series resistance (ESR) decreased with an increase in temperature for all SAIL-based electrolytes. We found that the supercapacitor cell with SAIL as an electrolyte has a high specific capacitance (C elec in F g–1), a high energy density (E in Wh kg–1), and a high power density (in W kg–1) compared to those for the binary mixture of SAIL with acetonitrile and for the 6 M KOH aqueous electrolytes, particularly at elevated temperatures. For the SAIL/MWCNT-based supercapacitor, C elec increased from 75 F g–1 at 298 K to 169 F g–1 at 373 K, whereas the energy density increased from 42 Wh kg–1 (at 298 K) to 94 Wh kg–1 (at 373 K) and the power density increased from 75 kW kg–1 (at 298 K) to 169 kW kg–1 (at 373 K) at a scan rate of 2 mV s–1 (potential window = 4 V). This study reveals that SAIL can potentially be used as an electrolyte for high-temperature electrochemical applications for energy storage devices.

This study deals with the concentration dependent apparent partition coefficients log P of the ethyl and bisulfate-based ionic liquids. It is observed that the bisulfate-based ionic liquids show different behaviour with respect to concentration as compared to ethyl sulphate-based ionic liquids. It is significant and useful analysis for the further implementation of alkyl sulfate based ionic liquids as solvents in extraction processes. The log P values of the ethyl sulphate-based ionic liquids were noted to vary linearly with the concentration of the ionic liquid, whereas a flip-flop trend with the concentration for the log P values of the bisulphate-based ionic liquids was observed due to the difference in hydrogen bond accepting basicity and possibility of aggregate formation of these anions. The π-π interactions between the imidazolium and pyridinium rings were seen to affect the log P values. The alkyl chain length of anions was also observed to influence the log P values. The hydrophobicity of ionic liquid changes with the alkyl chain in the anion in the order; [HSO4](-) < [EtSO4](-) < [BuSO4](-).

Abstract. The objectives of the current investigation were (1) to study the influence of selected two different non-solvents (diethylether and dichloromethane) on the drug crystal formation of a model drug, aspirin (ASP-I) by the modified vapor diffusion method and (2) to characterize and compare the generated crystals (ASP-II and ASP-III) using different analytical techniques with that of unprocessed ASP-I. When compared to the classical vapor diffusion method which consumes about 15 days to generate drug crystals, the modified method needs only 12 h to get the same. Fourier transform-infrared spectroscopy (FT-IR) reveals that the internal structures of ASP-II and ASP-III crystals were identical when compared with ASP-I. Although the drug crystals showed a close similarity in X-ray diffraction patterns, the difference in the relative intensities of some of the diffraction peaks (especially at 2θ values of around 7.7 and 15.5) could be attributed to the crystal habit or crystal size modification. Similarly, the differential scanning calorimetry (DSC) study speculates that only the crystal habit modifications might occur but without involving any change in internal structure of the generated drug polymorphic form I. This is further substantiated from the scanning electron microscopy (SEM) pictures that indicated the formation of platy shape for the ASP-II crystals and needle shape for the ASP-III crystals. In addition, the observed slow dissolution of ASP crystals should indicate polymorph form I formation. Thus, the modified vapor diffusion method could routinely be used to screen and legally secure all possible forms of other drug entities too.

Nickel and Cobalt bimetallic catalysts with Au as core metal has been synthesized and demonstrated for hydrazine decomposition reaction for producing hydrogen. Gold‐cobalt and gold nickel bimetallic system belonging to the class of strained structures with high lattice mismatch of approximately 14% are demonstrated for synergistic effects atypical of monometallic counterparts for the selective decomposition of hydrous hydrazine to H2 with N2 as the other product at room temperature.

RoekoSeal had the better sealing ability than GuttaFlow and may be recommended for clinical use.

This article describes the setting up of a facility on the energy‐scanning EXAFS beamline (BL‐09) at RRCAT, Indore, India, for operando studies of structure–activity correlation during a catalytic reaction. The setup was tested by operando X‐ray absorption spectroscopy (XAS) studies performed on a Co‐based catalyst during the Fischer–Tropsch reaction to obtain information regarding structural changes in the catalyst during the reaction. Simultaneous gas chromatography (GC) measurements during the reaction facilitate monitoring of the product gases, which in turn gives information regarding the activity of the catalyst. The combination of XAS and GC techniques was used to correlate the structural changes with the activity of the catalyst at different reaction temperatures. The oxide catalyst was reduced to the metallic phase by heating at 400°C for 5 h under H2 at ambient pressure and subsequently the catalytic reaction was studied at four different temperatures of 240, 260, 280 and 320°C. The catalyst was studied for 10 h at 320°C and an attempt has been made to understand the process of its deactivation from the XANES and EXAFS results.

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