Publications

N-Doped carbon dots (N-CDs) have been demonstrated as an effective co-catalyst for α-Fe₂O₃ nanorod arrays on a Ti sheet for photoelectrochemical water oxidation.

Some novel fluorinated quinazolines (<b>5a</b>-<b>j</b>) were designed and synthesized to be evaluated for their anticonvulsant activity and their neurotoxicity. Structures of all newly synthesized compounds were confirmed by their infrared (IR), mass spectrometry (MS) spectra, ¹H nuclear magnetic resonance (NMR), ¹³C-NMR, and elemental analysis (CHN). The anticonvulsant activity was evaluated by a subcutaneous pentylenetetrazole (scPTZ) test and maximal electroshock (MES)-induced seizure test, while neurotoxicity was evaluated by a rotorod test. The molecular docking was performed for all newly-synthesized compounds to assess their binding affinities to the GABA-A receptor in order to rationalize their anticonvulsant activities in a qualitative way. The data obtained from the molecular modeling was correlated with that obtained from the biological screening. These data showed considerable anticonvulsant activity for all newly-synthesized compounds. Compounds <b>5b</b>, <b>5c</b>, and <b>5d</b> showed the highest binding affinities toward the GABA-A receptor, along with the highest anticonvulsant activities in experimental mice. These compounds also showed low neurotoxicity and low toxicity in the median lethal dose test compared to the reference drugs. A GABA enzymatic assay was performed for these highly active compounds to confirm the obtained results and explain the possible mechanism for anticonvulsant action. The most active compounds might be used as leads for future modification and optimization.

Novel heterocyclic azomethine dyes were prepared by the reaction of anthracene-9-carbaldehyde with different heterocyclic amines under microwave irradiation. Structures of the azomethine dyes were confirmed by the elemental analysis, mass spectrometry and several spectroscopic techniques. We studied absorbance and fluorescence spectra of the azomethine dyes in various solvents. They are found to be good absorbers and emitters. We also report photophysical properties like, extinction coefficient, oscillator strength, stokes shift and transition dipole moment. This reflects physicochemical behaviors of synthesized dyes. In addition, their intramolecular charge transfer and nonlinear optical properties, supported by natural bond orbital technique, were also studied computationally by density functional theory. The negative nonlinear refractive index and nonlinear absorption coefficient were measured for these dyes using the closed and open aperture Z-scan technique with a continuous wave helium-neon laser. These are found to vary linearly with solution concentration.

In this current report, a simple, reliable, and rapid method based on modifying the cellulose surface by doping it with different percentages of lanthanum hydroxide (i.e., 1% La(OH)3-cellulose (LC), 5% La(OH)3-cellulose (LC2), and 10% La(OH)3-cellulose (LC3)) was proposed as a selective marker for detection of copper (Cu(II)) in aqueous medium. Surface properties of the newly modified cellulose phases were confirmed by Fourier transform infrared spectroscopy, field emission scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopic analysis. The effect of pH on the adsorption of modified cellulose phases for Cu(II) was evaluated, and LC3 was found to be the most selective for Cu(II) at pH 6.0. Other parameters, influencing the maximum uptake of Cu(II) on LC3, were also investigated for a deeper mechanistic understanding of the adsorption phenomena. Results showed that the adsorption capacity for Cu(II) was improved by 211% on the LC3 phase as compared to diethylaminoethyl cellulose phase after only 2 h contact time. Adsorption isotherm data established that the adsorption process nature was monolayer with a homogeneous adsorbent surface. Results displayed that the adsorption of Cu(II) onto the LC3 phase obeyed a pseudo-second-order kinetic model. Selectivity studies toward eight metal ions, i.e., Cd(II), Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Ni(II), and Zn(II), were further performed at the optimized pH value. Based on the selectivity study, it was found that Cu(II) is highly selective toward the LC3 phase. Moreover, the efficiency of the proposed method was supported by implementing it to real environmental water samples with adequate results.

Abstract The nonlinear optical (NLO) insights of triarylpyrazoline‐based (Z)‐2‐(2‐((7‐(4‐(5‐[2,4‐dimethylphenyl]‐1‐phenyl‐4,5‐dihydro‐1H‐pyrazol‐3‐yl)phenyl)‐4,4,9,9‐tetramethyl‐4,4a,9,10a‐tetrahydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophen‐2‐yl)methylene)‐3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐yl)malononitrile ( PR ) and its derivatives P1 – P7 were explored in this study. The compounds: PR and P1 – P7 having donor–π–acceptor configurations and M06/6‐311G(d,p) functional was selected to inquire the dipole moment ( μ ), linear polarizability ( α ), first hyperpolarizability ( β ), and second hyperpolarizability ( γ ). The findings of perturbed Kohn–Sham relations were deciphered to derive charge density of the molecules. The optical analysis was performed in gaseous phase and their findings were observed in 544.2–697.1 nm range. Moreover, the natural bond orbitals, frontier molecular orbitals, density of state, and transition density matrices for the aforesaid compounds were also calculated at aforesaid level. Global reactivity parameters of PR and P1 – P7 were analyzed by using highest occupied molecular orbital–lowest unoccupied molecular orbital energies. Overall, all above‐mentioned findings revealed significant optical nonlinear response in these pyrazoline‐based scaffold ( PR and P1 – P7 ). However, among all the compounds, P3 has shown the highest nonlinearity with maximum μ tot , &lt; α &gt;, β tot , and γ tot values at 19.4 D , 1.78 × 10 −22 , 2.57 × 10 −27 , and 3.13 × 10 −32 a.u ., respectively. Hence, the current computational study might prove to be fruitful for the exploration of proficient NLO materials for optoelectronic devices.

CoP nanotubes were fabricated by phosphidation of Co salt inside an anodic aluminum oxide template as an efficient hydrogen-evolving electrocatalysts.