Crystal structure of (E)-1-{[(3,5-dimethylphenyl)imino]methyl}naphthalen-2-ol

This is an open-access article distributed under the terms of the Creative Commons Attribution Licence.The title compound, C19H17NO, has an E conformation about the N=C bond. The mol­ecule is relatively planar, with the benzene ring and naphthalene ring plane being inclined to one another by 4.28 (10)°. There is an intra­molecular O—H⋯N hydrogen bond generating an S(6) ring motif. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, forming chains propagating along [100]. Within the chains there are π–π inter­actions involving the benzene ring and the naphthalene ring system of an adjacent mol­ecule [inter-centroid distance = 3.6405 (14) Å].We thank the Spanish Ministerio de Economía y Competitividad (MAT2013-40950-R and FPI grants: BES-2011-046948 to author MSMA) and the ERDF for financial support.Peer Reviewe

Nano Sized Moringa oleifera an Effective Strategy for Pb(II) ions Removal from Aqueous Solution

Nano-sized  Moringa oleifera is considered an effective   biosorbent  with  high surface area from agricultural waste, low coast and environment-friendly which can be used for removal of  Pb2+ from waste water. Thus our study stem to investigate the ability of natural nano-sized biosorbents for removing  very toxic Pb2+ ions from aqueous solution. The investigated biosorbent (Moringa oleifera) was characterized by FTIR, SEM, TEM, XRD and EDX techniques. Moreover, the influence of pH, temperature, adsorbent dosage, contact time and initial metal ion concentration on adsorption process were investigated. The maximum biosorption capacities (qm) of Pb2+ ions by Moringa oleifera was 37.9 mg/g. The lowest biosorption was observed (61.4%) for Pb2+ ions at pH 2.0 while the highest one (94.36%) at pH 5. The optimum contact time for the adsorption process was found to be at 60 minutes. The amount of Pb2+ ions adsorbed increases with increasing in initial metal ion concentration. Moreover, biosorption capacity (qe) and removal efficiency of Pb2+ ions solutions increase as temperature increases. FT-IR data indicated that the adsorption of metal ions occurs on the surface of Moringa oleifera powder as the main functional groups that are responsible for metal ions binding are involved in the process. Furthermore, Thermodynamic studies confirmed that the biosorption process was endothermic and the positive value of ΔG° is quite common when an ion-exchan­­ge mechanism applies in the biosorption. The Positive value of ΔS◦ suggested an increase in randomness during the biosorption. The kinetics study of sorption indicates that the pseudo second-order model provides better correlation of the sorption data (R2=0.99) than the pseudo first-order model (R2 = 0.91), confirming the chemisorption of metal ions solutions on Moringa oleifera. The Freundlich isotherm has agood fit with the experimental data (R2 close to 1) compared to Langmuir isotherm (R2=0.99). This study shows that Moringa oleifera are available, low cost, effective and environment friendlly biosorbent for the removal of Pb2+ ions from aqueous environment. Keywords: Lead, biosorption, Thermodynamics, kinetics, removal efficiency, Moringa oleifera, isother

Enhancement of exchange bias and perpendicular magnetic anisotropy in CoO/Co multilayer thin films by tuning the alumina template nanohole size

This work was financially supported by Spanish MCIU and AEI and European FEDER (MCIU-19-RTI2018-094683-B-C52 and PGC2018-099530-B-C31) and the Principado de Asturias (SVPA-21-AYUD/2021/51822)

A Simple and Reliable Synthesis of Superparamagnetic Magnetite Nanoparticles by Thermal Decomposition of Fe(acac)3

Magnetic nanoparticles have been largely proposed as means of technological tools due to its value in different fields, especially in biomedicine. Herein, we present a robust, highly reproducible and low-cost method to obtain superparamagnetic magnetite nanoparticles (MNP-II) of about diameter by thermal decomposition of [Fe(acac)3] in a one-pot, two-step method. In the first step, magnetite nanoparticles (MNP-I) of lower size, , with a saturation magnetization () of 65 emu/g and a coercive field () of 1 Oe are obtained. In the second step, those particles MNP-I act as seeds for the final MNP-II which present a saturation magnetization of 70 emu/g and a coercive field of 12 Oe.This work has been carried out within the project CTQ2017-86994-R of the Spanish Ministry of Economy, Industry and Competitiveness, and it was supported by the IUTA/Gijón Council under grants SV-17-Gijón-1-13 and SV-18-GIJÓN-1-14. Special acknowledgment is given to the Oviedo University Scientific and Technological Resources

Enhancement of Exchange Bias and Perpendicular Magnetic Anisotropy in CoO/Co Multilayer Thin Films by Tuning the Alumina Template Nanohole Size

The interest in magnetic nanostructures exhibiting perpendicular magnetic anisotropy and exchange bias (EB) effect has increased in recent years owing to their applications in a new generation of spintronic devices that combine several functionalities. We present a nanofabrication process used to induce a significant out-of-plane component of the magnetic easy axis and EB. In this study, 30 nm thick CoO/Co multilayers were deposited on nanostructured alumina templates with a broad range of pore diameters, 34 nm ≤ Dp ≤ 96 nm, maintaining the hexagonal lattice parameter at 107 nm. Increase of the exchange bias field (HEB) and the coercivity (HC) (12 times and 27 times, respectively) was observed in the nanostructured films compared to the non-patterned film. The marked dependence of HEB and HC with antidot hole diameters pinpoints an in-plane to out-of-plane changeover of the magnetic anisotropy at a nanohole diameter of ∼75 nm. Micromagnetic simulation shows the existence of antiferromagnetic layers that generate an exceptional magnetic configuration around the holes, named as antivortex-state. This configuration induces extra high-energy superdomain walls for edge-to-edge distance >27 nm and high-energy stripe magnetic domains below 27 nm, which could play an important role in the change of the magnetic easy axis towards the perpendicular directionEl interés por las nanoestructuras magnéticas que exhiben anisotropía magnética perpendicular y efecto de sesgo de intercambio (EB) ha aumentado en los últimos años debido a sus aplicaciones en una nueva generación de dispositivos espintrónicos que combinan varias funcionalidades. Presentamos un proceso de nanofabricación utilizado para inducir una componente significativa fuera del plano del eje magnético fácil y del EB. En este estudio, se depositaron multicapas de CoO/Co de 30 nm de espesor sobre plantillas de alúmina nanoestructurada con un amplio rango de diámetros de poro, 34 nm ≤ Dp ≤ 96 nm, manteniendo el parámetro de red hexagonal en 107 nm. Se observó un aumento del campo de polarización de intercambio (HEB) y de la coercitividad (HC) (12 veces y 27 veces, respectivamente) en las películas nanoestructuradas en comparación con la película sin patrón. La marcada dependencia de HEB y HC con los diámetros de los agujeros antidotados señala un cambio de la anisotropía magnética de dentro a fuera del plano a un diámetro de nanoagujero de ∼75 nm. La simulación micromagnética muestra la existencia de capas antiferromagnéticas que generan una configuración magnética excepcional alrededor de los agujeros, denominada estado de antivórtice. Esta configuración induce paredes de superdominio extra de alta energía para la distancia de borde a borde >27 nm y dominios magnéticos de franja de alta energía por debajo de 27 nm, que podrían desempeñar un papel importante en el cambio del eje magnético fácil hacia la dirección perpendicula

Synthesis, characterization and antibacterial activity studies of new 2‑pyrral‑L‑amino acid Schif base palladium (II) complexes.

Three new 2-pyrral amino acid Schif base palladium (II) complexes were synthesized, characterized and their activity against six bacterial species was investigated. The ligands: Potassium 2-pyrrolidine-L-methioninate (L1), Potassium 2-pyrrolidine-L-histidinate (L2) and Potassium 2-pyrrolidine-L-tryptophanate (L3) were synthesized and reacted with dichloro(1,5- cyclooctadiene)palladium(II) to form new palladium (II) complexes C1, C2 and C3, respectively. 1 NMR, FTIR, UV–Vis,elemental analysis and conductivity measurements were used to characterize the products. The antibacterial activities of the compounds were evaluated against Gram-positive Staphylococcus aureus (S. aureus, ATCC 25923), methicillin-resistant Staphylococcus aureus (MRSA, ATCC 33591), Staphylococcus epidermidis (S. epidermidis, ATCC 12228) and Streptococcus pyogenes (S. pyogenes, ATCC 19615) and, gram-negative Pseudomonas aeruginosa (P. aeruginosa, ATCC 27853) and Klebsiella pneumoniae (K. pneumoniae, ATCC 13883) using the agar well difusion assay and microtitre plate serial dilution method. The palladium complexes were active against the selected bacteria with the imidazole ring containing complex C2 and indole heterocyclic ring containing complex C3 showing the highest activity