Volume 2 Issue 1
Authors: Sudesh Kumar Yadav; Vineet Kumar
Abstract: Syzygium cumini is well known for its medicinal properties. This plant has shown potential for gold nanoparticles (GNP) synthesis. In the present study, we have varied physiochemical factors (metal ion, leaf extract ratio and incubation temperature) to see the influence on GNP size. GNPs of 13 to 70 nm size were synthesized by varying these parameters. The NPs thus synthesized through greener route and capped by medicinally important constituents can be very useful for applications in which products come in direct human contact.
Keywords: S. Cumini; GNP; Physiochemical Factors; Greener Route
Authors: S. Ramesh
Abstract: The Ag3(2+x)GdxTi4-xO11+δ (0.0 ≤ x ≤ 1.0) (x = 0, 0.25, 0.5, 0.75 and 1.0) nanocomposites were successfully synthesized by sol-gel technique. The surface morphology, structure and the properties of nanocomposites were investigated by SEM, XRD, DTA, IR, UV, EPR and VSM. The XRD result reveals that the composites were formed in Tetragonal lattice type with P42/nnm space group. The average crystallite size of the composites varied from 44 nm to 63 nm. The surface morphology of the samples was evaluated by SEM. The purity of the composites was confirmed through the Energy Dispersive X-ray analysis. Electron paramagnetic resonance lineshapes were recorded at 8 K, 77 K and 300 K which are isotropic in nature. The magnetic susceptibility values of the samples are in ferromagnetic nature at room temperature.
Keywords: Composite Materials; Sol-gel Processes; Electron Paramagnetic Resonance; X-ray Diffraction; Hysteresis Loop
Authors: Tooba Abdizadeh; Masoud Nasr-Esfahani
Abstract: Biologically active 1,8-dioxooctahydroxanthenes were prepared by a one-pot condensation reaction of 1,3-cyclohexanediones and aldehydes in presence of Vanadatesulfuric acid nanorods (VSA NRs) as a novel, recyclable and eco-benign catalyst under solvent-free conditions in high to excellent yields (75–93%) and in short reaction times (10-60 min). The catalyst was characterized by FT-IR, XRD, TEM and SEM analysis. The present method offers several advantages such as simple procedure, short reaction times, high yields, simple workup, reusability of the catalyst and simple purification of the products.
Keywords: 1,8-Dioxooctahydroxanthenes; Heterogeneous Aatalysis; Vanadatesulfuric Acid; Solvent-Free; Acid Catalysis; Nanorod Particles
Authors: Charlotte A. E. Hauser; Wei Yang Seow
Abstract: Hydrogels provide a three-dimensional polymeric network and are useful as matrices for the delivery of therapeutics or as scaffolds for tissue engineering. However, the sol-gel transition of hydrogels can be difficult to quantify and methods commonly used to study gelation kinetics such as visual inspection, rheology or light scattering have their limitations. Using polyacrylamide, gelatin and poly (hydroxyethyl) methacrylate gels as model systems, we now show that the surface tension of a gelling system can be used to monitor its transition from an initially free-flowing solution state into a gel capable of supporting its own weight in an inverted container. This method is automated, minimally-invasive and samples can be easily recovered after measurements. It can potentially be applied to other gel systems to provide a rapid, simple and objective comparison of gelation kinetics.
Keywords: Hydrogel; Gelation Kinetics; Surface Tension; Gel Formation