Green Synthesis and Investigation of Surface Effects of α-Fe2O3@TiO2 Nanocomposites by Impedance Spectroscopy.

Nanocomposites based on iron oxide/titanium oxide nanoparticles were prepared by employing green synthesis, which involved phytochemical-mediated reduction using ginger extract. XRD confirmed the composite formation, while scanning electron microscopy (SEM), dynamic light scattering (DLS), and energy-dispersive X-ray spectroscopy (EDX) was employed to investigate the particle size, particle morphology, and elemental analysis. SEM indicated the formation of particles with non-uniform shape and size distribution, while EDX confirmed the presence of Fe, Ti and oxygen in their elemental state. The surface effects were investigated by Fourier transform infrared radiation (FTIR) and impedance spectroscopy (IS) at room temperature. IS confirmed the co-existence of grains and grain boundaries. Thus, FTIR and IS analysis helped establish a correlation between enhanced surface activity and the synthesis route adopted. It was established that the surface activity was sensitive to the synthesis route adopted. The sample density, variation in grain size, and electrical resistivity were linked with surface defects, and these defects were related to temperature. The disorder and defects created trap centers at the sample's surface, leading to adsorption of CO2 from the environment.

Biodiesel Production from Alkali-Catalyzed Transesterification of Tamarindus indica Seed Oil and Optimization of Process Conditions.

Biodiesel is considered a sustainable alternative to petro-diesel owing to several favorable characteristics. However, higher production costs, primarily due to the use of costly edible oils as raw materials, are a chief impediment to its pecuniary feasibility. Exploring non-edible oils as raw material for biodiesel is an attractive strategy that would address the economic constraints associated with biodiesel production. This research aims to optimize the reaction conditions for the production of biodiesel through an alkali-catalyzed transesterification of Tamarindus indica seed oil. The Taguchi method was applied to optimize performance parameters such as alcohol-to-oil molar ratio, catalyst amount, and reaction time. The fatty acid content of both oil and biodiesel was determined using gas chromatography. The optimized conditions of alcohol-to-oil molar ratio (6:1), catalyst (1.5% w/w), and reaction time 1 h afforded biodiesel with 93.5% yield. The most considerable contribution came from the molar ratio of alcohol to oil (75.9%) followed by the amount of catalyst (20.7%). In another case, alcohol to oil molar ratio (9:1), catalyst (1.5% w/w) and reaction time 1.5 h afforded biodiesel 82.5% yield. The fuel properties of Tamarindus indica methyl esters produced under ideal conditions were within ASTM D6751 biodiesel specified limits. Findings of the study indicate that Tamarindus indica may be chosen as a prospective and viable option for large-scale production of biodiesel, making it a substitute for petro-diesel.

A facile sonochemical protocol for synthesis of 3-amino- and 4-amino-1,2,4-triazole derived Schiff bases as potential antibacterial agents.

A facile method has been developed for the synthesis of Schiff bases derived from substituted and unsubstituted 3-amino- and 4-amino-1,2,4-triazoles. Condensation of the aminotrizoles with a variety of aromatic aldehydes afforded desired Schiff bases in excellent yields in 3-5 minutes of exposure to ultra-sound. The synthesized compounds were characterized by means of IR, 1HNMR and Mass spectrometry. The synthesized compounds were also screened for their antibacterial potential against Gram-negative (Escherichia coli, Shigella sonnei, Pseudomonas aeruginosa and Salmonella typhi) and two Gram-positive (Staphylococcus aureus and Bacillus subtilis) strains.

Evaluation of silica-H2SO4 as an efficient heterogeneous catalyst for the synthesis of chalcones.

We report an efficient silica-H2SO4 mediated synthesis of a variety of chalcones that afforded the targeted compounds in very good yield compared to base catalyzed solvent free conditions as well as acid or base catalyzed refluxing conditions.

2,4-Dibromo-naphthalen-1-ol.

In the essentially planar (r.m.s. deviation = 0.023 Å) title compound, C(10)H(6)Br(2)O, an intra-molecular O-H⋯Br hydrogen bond generates an S(5) ring. In the crystal, mol-ecules are linked by an ⋯O-H⋯O-H⋯O- C(2) chain extending along [100], which involves the same H atom that participates in the intra-molecular hydrogen bond. Aromatic π-π inter-actions [centroid-centroid separation = 3.737 (4) Å] help to consolidate the packing.

4-Hy-droxy-2-methyl-3,4-diphenyl-cyclo-pent-2-en-1-one.

The asymmetric unit of title compound, C(18)H(16)O(2), contains two mol-ecules with slightly different conformations. In the first mol-ecule, the two phenyl rings make dihedral angles of 84.98 (11)° and the five-membered ring makes dihedral angles of 84.80 (12) and 73.00 (12)° with the phenyl rings; the corresponding angles for the second mol-ecule are 86.74 (11), 81.20 (13) and 71.36 (12)°. O-H⋯O hydrogen bonds between the hy-droxy and carbonyl groups are a feature of the crystal packing, which results in chains extending parallel to [100]. Weak C-H⋯O and C-H⋯π inter-actions are also observed.

2,4-Dinitro-1-naphthol.

In the title compound, C(10)H(6)N(2)O(5), the two fused rings are almost co-planar, with an r.m.s. deviation of 0.0163 Å. The nitro groups are oriented at dihedral angles of 2.62 (11) and 44.69 (11)° with respect to the plane of the parent fused rings. Intra-molecular O-H⋯O and C-H⋯O hydrogen bonds complete S(6) ring motifs. In the crystal, mol-ecules are linked into chains along [101] by inter-molecular O-H⋯O hydrogen bonds. π-π inter-actions [centroid-centroid distances = 3.6296 (15), 3.8104 (15) and 3.6513 (14) Å] might play a role in stabilizing the structure.