ZnO/CdO/reduced graphene oxide and its high catalytic performance towards degradation of the organic pollutants

ZnO/CdO nanoparticles on the reduced graphene oxide (ZnO/CdO/ /reduced graphene oxide) were prepared by a hydrothermal process. The structure and morphology were investigated by FTIR, UV-Vis, XRD, EDX, DRS, SEM and TEM. The sonocatalytic properties of ZnO/CdO/reduced graphene oxide were evaluated in the degradation of mefenamic acid (MEF), methyl orange (MO), rhodamin (RhB) and 4-nitroaniline (4-NA). Based on the results, the effective and high efficiency of the degradation of azo dyes (MO: 84 %, RhB: 80 %), MEF: 93 % and 4-NA: 95 % were observed in 120 min after the beginning of the reactions. The effects of factors such as ZnO/CdO/reduced graphene oxide dosage, initial concentration of organic pollutant, ultrasonic power and the presence of ROS (reactive oxygen species) scavengers on the degradation efficiency were reviewed. It was found that the presence of scavengers suppressed the sonocatalytic degradation efficiency. This research indicates the as-prepared nanocomposites exhibit much higher catalytic activity than ZnO/CdO nanoparticles and reduce graphene oxide (rGO)

Solvent-dependent synthesis and mono-hydrolysis of di-Schiff base of (+/-)trans-1,2-cyclohexanediamine and 2-pyridinecarboxaldehyde in Cu(II), Co(II) and Zn(II) complexes

The Schiff base ligand trans-N,N′-bis[2-pyridinecarboxylidene] cyclohexane-1,2-diamine (L) was synthesized. This ligand when stirred with 1 equiv of MCl2.xH2O (M = Cu, Co, Zn) in ethanol, undergoes partial hydrolysis of the imino bond and the result tridentate ligand (L') and immediately forms the complexes with N3 coordination sphere. The reactions of L with MCl2.xH2O (M = Cu, Co, Zn) in THF give complexes [ML]Cl2. The ligand (L), complexes [M(L')Cl]Cl and [ML]Cl2 were characterized by elemental analysis, UV-Vis, FT-IR, 1H NMR, GC/MS and luminescence properties. The 1H NMR spectra of the ligand and its diamagnetic complexes were recorded in CDCl3 and DMSO solvents, respectively. Obtained data confirm that the donor atoms N in ligand coordinated to the metal ions. The luminescence studies show ligands and their complexes display intraligand (π-

Copper(II) complex of (±)trans-1,2-cyclohexanediamine azo-linked Schiff base ligand encapsulated in nanocavity of zeolite-Y for the catalytic oxidation of olefins

A Schiff base ligand derived from 4-(benzeneazo) salicylaldehyde and (±)trans-1,2-cyclohexanediamine (H2L) and its corresponding Cu(II) complex (CuL) has been synthesized and characterized by FT-IR, UV-VIS and 1H NMR. The copper Schiff base complex encapsulated in the nanopores of zeolite-Y (CuL-Y) by flexible ligand method and its encapsulation have been ensured by different studies. The homogeneous and its corresponding heterogeneous catalysts have been used for oxidation of different alkenes with tert-butyl hydroperoxide. Under the optimized reaction conditions, the oxidation of cyclooctene, cyclohexene, styrene and norbornene catalyzed by CuL gave 89, 63, 46 and 13% conversion, respectively. These olefins were oxidized efficiently with 50, 96, 96 and 92% conversion in the presence of CuL-Y, respectively. Comparison of the catalytic behavior of CuL and CuL-Y showed the higher catalytic activity and selectivity of the heterogeneous catalyst with respect to the homogenous one

Therapeutic potential of hair follicle-derived stem cell intranasal transplantation in a rat model of ischemic stroke

Background Stem cell-based therapy has received considerable attention as a potential candidate in the treatment of ischemic stroke; however, employing an appropriate type of stem cells and an effective delivery route are still challenging. In the present study, we investigated the therapeutic effect of safe, noninvasive, and brain-targeted intranasal administration of hair follicle-derived stem cells (HFSCs) in a rat model of ischemic stroke. Methods Stem cells were obtained from the adult rat hair follicles. In experiment 1, stroke was induced by 30 min middle cerebral artery occlusion (MCAO) and stem cells were intranasally transplanted immediately after ischemia. In experiment 2, stroke was induced by 120 min MCAO and stem cells were administered 24 h after cerebral ischemia. In all experimental groups, neurological performance, short-term spatial working memory and infarct volume were assessed. Moreover, relative expression of major trophic factors in the striatum and cortex was evaluated by the quantitative PCR technique. The end point of experiment 1 was day 3 and the end point of experiment 2 was day 15. Results In both experiments, intranasal administration of HFSCs improved functional performance and decreased infarct volume compared to the MCAO rats. Furthermore, NeuN and VEGF expression were higher in the transplanted group and stem cell therapy partially prevented BDNF and neurotrophin-3 over-expression induced by cerebral ischemia. Conclusions These findings highlight the curative potential of HFSCs following intranasal transplantation in a rat model of ischemic stroke.UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí