Modified Eu3+ doped Y2O3 Nanoparticles as Turn-on Fluorescence Sensor for Sensitive Determination of Methamphetamine

Journal of Analytical Chemistry - In this article, a new spectrofluorometric method was developed for the determination of methamphetamine based on a turn-on luminescence response of captopril...     

Influence of counter-anion on the coordination geometry of manganese(II) complexes with methyl-2-pyrazinecarboximidate ligand

Two new complexes of [Mn(2-MPyzCI)₂Cl₂].H²O (1) and [Mn(2-MPyzCI)₂(H₂O)₂](NO₃)₂ (2) were synthesized from the reaction of MnX₂.4H₂O (X=Cl^? and NO₃^?) with 2-cyanopyrazine in methanolic solution. The chelating methyl pyrazine-2-carboximidate (2-MPyzCI) ligand is formed via the methanolysis of 2-cyanopyrazine. Although coordination environment around manganes(II) ions is similar, but these complexes are different in geometrical position of 2-MPyzCI ligands. As both compounds are synthesized under the same reaction conditions, the only difference between these two complexes are counter ions and changing of geometrical position of ligands can be considered as a result of influence of the counter-anions on the molecular structures.     

Torsional vibration of functionally graded nano-rod under magnetic field supported by a generalized torsional foundation based on nonlocal elasticity theory

Abstract

This article contains the nonlocal elasticity theory to capture size effects in functionally graded (FG) nano-rod under magnetic field supported by a torsional foundation. Torque effect of an axial magnetic field on an FG nano-rod has been defined using Maxwell’s relation. The material properties were assumed to vary according to the power law in radial direction. The Navier equation and boundary conditions of the size-dependent FG nano-rod were derived by the Hamilton’s principle. These equations were solved by employing the generalized differential quadrature method (GDQM). Presented model has the ability to turn into the classical model if the material length scale parameter is taken to be zero. The effects of some parameters, such as inhomogeneity constant, magnetic field and small-scale parameter, were studied. As an important result of this study can be stated that an FG nano-rod model based on the nonlocal elasticity theory behaves softer and has smaller natural frequency.     

Energy and exergy analysis of a novel turbo-compounding system for supercharging and mild hybridization of a gasoline engine

Journal of Thermal Analysis and Calorimetry - Number of hybrid vehicles has increased around the world significantly. Automotive industry is utilizing the hybridization of the powertrain system to...     

Novel nanocomposite membranes prepared with PVC/ABS and silica nanoparticles for C<Subscript>2</Subscript>H<Subscript>6</Subscript>/CH<Subscript>4</Subscript> separation

Composite membranes based on polyvinyl chloride and acrylonitrile butadiene styrene (ABS) copolymer have been prepared and then filled with 2–8 wt % of silica nanoparticles. Membranes were fabricated by solution casting method using dimethylacetamide. The performance of prepared membranes were studied for methane and ethane at the feed pressure of 1.0, 1.5, 2.0, and 3.0 bar at 35°C. By increasing the percentage of ABS, permeability of methane and ethane increased. In addition, by adding the silica nanoparticles in the membrane, permeability of gas increased in all cases. The highest gas pair selectivity for C₂H₆/CH₄ could be obtained from PVC/BS (20 wt %) which loaded with 8 wt % of silica nanoparticles. The results of this study suggest that high performance gas separation nanocomposite membranes can be attained by adopting a judicious combination of blending technique for polymeric membrane, optimized loading percentage, and feed operating conditions.     

Response surface optimization of heterogeneous Fenton-like degradation of sulfasalazine using Fe-impregnated clinoptilolite nanorods prepared by Ar-plasma

Research on Chemical Intermediates - Optimization of sulfasalazine degradation using the heterogeneous Fenton-like process in batch mode was investigated by response surface methodology. The...     

Synthesis of 2‐Aryl‐5‐oxo‐4‐[2‐(phenylmethylidene)hydrazino]‐2,5‐dihydro‐1H‐pyrrole‐3‐carboxylates by the Reaction between Hydrazones,Acetylenedicarboxylates, and 1‐Aryl‐N,N′‐bis(arylmethylidene)methanediamines

An efficient approach for the preparation of functionalized 2‐aryl‐2,5‐dihydro‐5‐oxo‐4‐[2‐(phenylmethylidene)hydrazino]‐1H‐pyrroles is described. The four‐component reaction between aldehydes, NH₂NH₂?H₂O, dialkyl acetylenedicarboxylates, and 1‐aryl‐N,N′‐bis(arylmethylidene)methanediamines proceeds in EtOH under reflux in good‐to‐excellent yields (Scheme 1). The structures of 4 were corroborated spectroscopically (IR, ¹H‐ and ¹³C‐NMR, and EI‐MS, and, in the case of 4f , by X‐ray crystallography). A plausible mechanism for this type of reaction is proposed (Scheme 2).     

Preparation of chitosan functionalized end‐capped Ag‐NPs and composited with Fe3O4‐NPs: Controlled release to pH‐responsive delivery of progesterone and antibacterial activity against pseudomonas aeruginosa (PAO‐1)

In this work, functionalized chitosan end‐capped Ag nanoparticles (NPs) and composited with Fe₃O₄‐NPs was prepared as pH‐responsive controlled release carrier for gastric‐specific drug delivery. The structure of prepared material was characterized by FE‐SEM, XRD, EDS and FT‐IR analysis. The loading behavior of the progesterone onto this novel material was studied in aqueous medium at 25°C and their release was followed spectrophotometrically at 37°C in seven different buffer solutions (pH 1.2, 2.2, 3.2, 4.2, 5.2, 6.2 and 7.2) to simulate intestine and gastric media which experimental results reveal more release rate in pH 1.2 (gastric medium) with respect to other buffers. This observation is attributed to dependency of the CS‐IMBDO‐Ag‐Fe₃O₄‐NPs and progesterone structure with buffer pH that candidate this new material as prospective pH‐sensitive carrier for gastric‐targeted drug delivery. On the other hand, the antibacterial properties of this material against gram‐negative bacterium pseudomonas aeruginosa (PAO‐1) in agar plates was studied and accordingly based on broth micro dilution the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) with respect to standard CLSI in different concentrations of CS‐IMBDO‐Ag‐Fe₃O₄‐NPs was calculated. The results reveal that MIC and MBC values are 50 and 1250 μg/mL, respectively. In addition, extracts of Portulaca oleracea leaves was prepared and its antibacterial activity in single and binary system with CS‐IMBDO‐Ag‐Fe₃O₄‐NPs as synergies effect against PAO‐1 was tested and results shown that these materials have significant synergistic effect for each other.