a practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °c was described. the reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. all reactions performed effic...

TiCl4/nano-cellulose as a biodegradable and eco-friendly Lewis acid catalyst was synthesized via reaction of nano-cellulose and TiCl4. This catalyst was characterized and used for synthesis of asymmetric highly functionalized tetrahydropyridines via a five-component condensation reaction of p-substituted anilines, aldehydes and ethyl acetoacetate under solvent-free condition. Simple methodology...

We look at the magnetic field induced weak localisation peak of graphene samples with different mobilities. At very low temperatures, low mobility samples exhibit a very broad peak as a function of the magnetic field, in contrast to higher mobility samples, where the weak localisation peak is very sharp. We analyze the experimental data in the context of the localisation length, which allows us...

We report that the substrate-free gas-phase graphene synthesis method produces clean and highly ordered graphene sheets that are similar in quality to the graphene obtained through the mechanical exfoliation of highly oriented pyrolytic graphite.

Petro physics, rock physics and multi-attribute analysis have been employed in an integrated approach to delineate porosity variation across Tamag Field of Niger Delta Basin. Gamma and resistivity logs were employed to identify sand bodies and correlated across the field. Petro physical analysis was undertaken. Rock physics modelling and multi-attribute analysis were carried out. Two hydrocarbo...

a highly efficient, simple and clean solvent-free protocol for the synthesis of polyhydroquinolines is described. the one-pot multi-component condensation reaction between arylaldehydes, dimedone (5,5-dimethylcyclohexane-1,3-dione), β-ketoesters and ammonium acetate in the presence of catalytic amount of (2.5 mol%) melamine trisulfonic acid (mtsa) as a recyclable, green and attractive sulfonic ...

Many modern analytical methods deal with the trace-level determination of compounds of interest in highly complex environmental samples by means of chromatographic techniques. The introduction of a “clean” sample into an analytical instrument can make analyses easier and prolongs the equipment life. The use of solid-phase extraction (SPE) has grown and is a fertile technique of sample prepa...