Publications

The interaction between novel gemini surfactant (alkane-α, ω-bis(dimethyl hexadecyl ammonium bromide) (G6)) and two different non-ionic surfactants (Triton X-114 (TX-114), Tween 20 (T-20)) has been investigated in the current study at temperature 298.15 K. The critical micelle concentration (cmc) values of mixed systems were computed by the conductometric titration in the aqueous medium. The results have been examined by utilizing numerous theoretical models (Clint, Rubingh, Motomura, Maeda, and Lange models). The experimentally determined cmc were lower than corresponding ideal values (cmc*) and decreased with the mixtures' stoichiometric mole fraction (α1) of G6. This shows non-ideal behavior between two employed components. The interaction parameter at mixed micelle (β) has been analyzed by using regular solution approximation. The attractive interaction or synergistic behavior in both mixed systems is confirmed by the negative values of β. The various energetics parameters were also evaluated and discussed.

Ambient electrochemical N2 reduction offers a promising alternative to the energy-intensive Haber-Bosch process towards renewable NH3 synthesis in aqueous media but needs efficient electrocatalysts to enable the N2 reduction reaction (NRR). Herein, we propose that an amorphous WC thin film magnetron sputtered onto a graphite foil behaves as a superb NRR electrocatalyst for ambient NH3 production with excellent selectivity. In 0.5 M LiClO4, it attains a large NH3 yield of 43.37 μg h-1 mg-1cat. and a high faradaic efficiency of 21.65% at -0.10 V vs. reversible hydrogen electrode. Impressively, this catalyst also shows excellent selectivity and strong durability for NH3 formation.

A new class of conductive metal-organic framework (MOF), polyaniline- aluminum succinate (PANI@Al-SA) nanocomposite was prepared by oxidative polymerization of aniline monomer using potassium persulfate as an oxidant. Several analytical techniques such as FTIR, FE-SEM, EDX, XRD, XPS and TGA-DTA were utilized to characterize the obtained MOFs nanocomposite. DC electrical conductivity of polymer-MOFs was determined by four probe method. A bare glassy carbon electrode (GCE) was modified by nafion/PANI@Al-SA, and examined for Zn (II) ion detection. Modified electrode showed improved efficiency by 91.9%. The modified electrode (PANI@Al-SA/nafion/GCE) exhibited good catalytic property and highly selectivity towards Zn(II) ion. A linear dynamic range of 2.8-228.6 µM was obtained with detection limit of LOD 0.59 µM and excellent sensitivity of 7.14 µA µM^-1 cm^-2. The designed procedure for Zn (II) ion detection in real sample exhibited good stability in terms of repeatability, reproducibility and not affected by likely interferents. Therefore, the developed procedure is promising for quantification of Zn(II) ion in real samples.

Interaction between the anionic and nonionic surfactant at bulk and air/water interface has been studied. The synergistic interaction between surfactants was found in both in bulk solution as well as the interface. The different physicochemical parameters of the free surfactant monomers up to the point of their critical micelle concentration (cmc) have been evaluated and discussed in detail. The synergistic interactions have been analyzed using various theoretical models reported i.e., Clint, Rubingh, Maeda and Rosen models. The spectrophotometric and structural analyses have been achieved for the formation of silver nanoparticles using sodium borohydride as reducing agents and pure as well as mixed surfactant systems as capping agents. Antimicrobial activities of the synthesized nanoparticles were performed against both Gram-negative (P. aeruginosa and Klebsiella Pneumonia) and Gram- positive (Micrococcus luteus) bacteria.

Abstract Two different approaches to the title compounds are elaborated using either substituted 7‐azacoumarins, enolizable ketones and primary amines [cf.

TiC/C nanofibers (TiC/C NFs) act as an efficient 1-D electrocatalyst for N₂-to-NH₃ fixation, capable of achieving a large NH₃ yield of 14.1 μg h⁻¹ mg⁻¹_cat. and a high faradaic efficiency of 5.8% at −0.5 V <italic>vs.</italic> RHE in 0.1 M HCl.

Cefixime trihydrate (CMT) has the usages to treat the bacterial infections of urinary tract, throat, ear & tonsils. Herein, the current investigation describes the interaction of CMT with dodecyltrimethylammonium Bromide (DTAB) by means of the conductivity measurement method in H2O and aq. solutions of NaBr, Na2SO4, and Na3PO4. The experiments were carried out at 310.55 K for several concentrations of CMT/ salts and temperatures of 300.55−320.55 K for one particular concentration of CMT/ salts employed. In every case, a single critical micelle concentration (CMC) has been achieved. The addition of CMT augments the aggregation of DTAB. The CMC values of the DTAB + CMT mixture undergo a decrease in attendance of electrolytes in comparison to water medium. In the manifestation of electrolytes, the CMC values of DTAB + CMT mixed systems at 310.55 K and ionic strength of 1 mmol kg−1 follow the order: CMC (H2O + NaBr) > CMC (H2O + Na2SO4) > CMC (H2O + Na3PO4). The negative ΔG°m values indicated that the micellization of DTAB + CMT mixture was spontaneous. The -ΔH°m and +ΔS°m values disclose that the assembly of DTAB + CMT mixture in aqueous medium is both enthalpy & entropy-controlled process. The thermodynamics of transfer and enthalpy-entropy compensation have also been described in the ongoing study.