Investigation of the Electrochemical Behavior of Mesalazine on the Surface of a Glassy Carbon Electrode Modified with CNT/PPY Doped by 1,5‐Naphthalenedisulfonic Acid

A glassy carbon electrode (GCE) was modified with a thin layer of multiwalled carbon nanotubes (MWCNTs) and subsequently, electrochemically deposited poly‐pyrrole. The electrochemical behavior of mesalazine was studied on the surface of the modified electrode by applying linear sweep voltammetry (LSV). The electropolymerization process and the electrochemical response toward mesalazine were investigated in the presence of different aromatic anion dopants including, benzenesulfonic acid (BSA), 1,3‐benzenedisulfonic acid (1,3‐BDSA), 1,5‐naphthalenedisulfonic acid (1,5‐NDSA) and new coccine (NC). By using 1,5‐NDSA as dopant, a significant increase (～418 times) in the peak current of mesalazine was observed, in comparison to the bare GCE. Experimental variables such as drop size of the cast MWCNTs suspension, pH of the supporting electrolyte, accumulation conditions and the number of scans in the electropolymerization process were optimized by monitoring the LSV responses of mesalazine. Under the optimum conditions, two linear dynamic ranges of 0.01–0.1 µmol L^?1 and 0.1–1.0 µmol L^?1 with a detection limit of 3 nmol L^?1 were resulted for the voltammetric determination of mesalazine. The prepared electrode showed high sensitivity, stability and good reproducibility for determination of mesalazine. These properties made the prepared sensor suitable for the determination of mesalazine in pharmaceutical and clinical preparations.     

Synthesis of benzo[h]quinolone and benzo[c]acridinone derivatives by Fe3O4@PS-Arginine[HSO4] as an efficient magnetic nanocatalyst

Fe₃O₄ magnetic nanoparticles were synthesized and functionalized by propylsilan and after that arginine. The synthesized Fe₃O₄@PS-Arginine magnetic nanoparticles were modified to obtain Fe₃O₄@PS-Arg[HSO₄]. These nanoparticles were used as environmental friendly solidacid magnetic nanocatalyst for the synthesis of 2-amino-4-arylbenzo[h]quinoline-3-carbonitrile and 10,10-dimethyl-7-aryl-9,10,11,12-tetrahydrobenzo[c]acridin-8(7H)-one derivatives via the one-pot reaction of α-naphthilamine and aromatic aldehydes with malononitrile or dimedone. Simple operation, high reaction yields, reusability of catalyst for several times, short reaction time and easy separation from reaction mixture are the key advantages of using this catalyst.     

Manganese(III) porphyrin supported on multi-wall carbon nanotubes: A highly efficient and reusable biomimetic catalyst for epoxidation of alkenes with sodium periodate

In this paper, the biomimetic epoxidation of alkenes catalyzed by tetrakis(p-aminophenyl)porphyrinatomanganese(III) chloride, [Mn(TNH₂PP)Cl], supported on functionalized multi-wall carbon nanotubes, MWCNT, is reported. The catalyst, [Mn(TNH₂PP)Cl-MWCNT], was used as an efficient and heterogeneous catalyst for epoxidation of alkenes with NaIO₄ at room temperature, in the presence of imidazole as an axial ligand. This new heterogenized catalyst was characterized by elemental analysis, FT IR spectroscopy, diffuse reflectance UV–Vis spectrophotometry, scanning electron microscopy and transmission electron microscopy. The biggest advantage of Mn(TNH₂PP)Cl-MWCNT is its high reusability in the oxidation reactions, in which the catalyst was reused several times without significant loss of its catalytic activity.     

Synthesis,crystal structure,spectroscopic investigations,and computational studies of Ni(II) and Pd(II) complexes with asymmetric tetradentate NOON Schiff base ligand

Structural Chemistry - In the present study, an asymmetric tetradentate NOON Schiff base ligand 2,2′-((4-methyl-1,2-phenylene)bis(nitrilomethylylidene))bis(4-chlorophenol) (H2L) was...     

Synthesis,characterization, crystal structures and antibacterial activities of some Schiff bases with N<Subscript>2</Subscript>O<Subscript>2</Subscript> donor sets

A series of Schiff base compounds were synthesized by the reaction of different 3,5-dihalosalicylaldehyde (halo atoms equal to Cl, Br and I) with polymethylenediamines of varying chain length. The Schiff bases were characterized using FT-IR, UV–Vis, ¹H NMR, ¹³C NMR and mass spectroscopic techniques, and elemental analyses (CHN), and crystal structure of some compounds was determined by X-ray crystallography. The in vitro biological screening effects of the synthesized compounds were tested against different microbial kinds. The results revealed that all compounds were biologically active.     

Effective permeability of cracked unsaturated porous materials

This study focuses on a theoretical estimation of the effective permeability of unsaturated cracked porous media. The closed-form flow solution around and in a superconductive crack, embedded in an infinite porous matrix under a far-field condition, is recalled first. Then the solution of flow around a completely unsaturated (empty) crack that is considered as an obstruction against the flow is determined. The flow solution for partially saturated crack in special configurations is obtained by superposition of the two basic solutions for superconductive and empty cracks. The contribution of an unsaturated crack, with a given saturation degree, to the effective permeability is estimated by using dilute upscaling scheme. Numerical results obtained by Finite Elements Method, are in good agreement with the theoretical results for weak crack densities but show the additional effect of cracks interaction for higher densities.     

Effect of CH3NH3I/CH3NH3Br precursors on the structural and surface morphology properties of the electrodeposited methylammonium lead–mixed halide perovskite films

Journal of Solid State Electrochemistry - Organometallic halide perovskites have been arisen as a class of multi-purpose materials with exciting applications in optoelectronic devices such as solar...     

Three-dimensional gap plasmon power splitters suitable for photonic integrated circuits

In this paper we have investigated the performance of a nano-optical power splitter based on gap plasmon waveguides. The structure consists of the rectangular gap plasmon waveguides in metal films. It is clear that the wave number and correspondingly light confinement and the loss in the waveguides are the most effective parameters in power splitting, but as we know coupling length is another important factor which should be considered. Some dependencies of the coupling length and the maximum transfer power on the structure parameters are studied. It has been shown that approximately 43% transfer power for each arm of the splitter is achievable. Simulation results have been obtained by the compact finite-difference time-domain method. The considered structures, because of their small coupling length and dimensions are appropriate for implementation in photonic integrated circuits.