Sodium Alginate, Nanoclay And Curcumin Based Food Packaging Material For Intelligent Food Packaging Applications

Bionanocomposite food packaging contains materials of biological origin which display high-performance activity when compared to biopolymers and are eco-friendly alternatives to conventional packaging materials. Intelligent packaging monitors the condition of the food or environment surrounding the food and communicates changes to the consumer. This study aimed to develop a bionanocomposite intelligent packaging material by utilising sodium alginate, nanoclay and curcumin. Sodium alginate (2 W/V% SA) film incorporated with 0.3 W/V% curcumin (Cur), glycerol, and nanoclay (NC) in various concentrations (0, 0.5, 1 and 2 W/V %) was prepared using the solvent casting method. The influences of nanoclay and curcumin on the optical, mechanical, physical, chemical, thermal, and pH sensing properties were studied. Results showed that the films were of high colouration and low transparency with a ΔE*\u3e 4 as compared to the control film. Among all the developed films, the SA_Cur_2%NC film was the thickest (0.072 ± 0.00mm) and showed the most effective UV barrier property. It has been observed that with the increasing NC concentrations, transparency of the films decreased while there was an enhancement in the UV barrier property. SA_Cur_1%NC had the highest mechanical properties with high tensile strength (14.68 ± 1.06 MPa), elongation at break (3.31 ± 0.62%) and Young’s modulus (0.93 ± 0.02MPa). When compared with the control film (SA_Cur_0%W/V NC) the tensile strength increased more than two folds. It has been observed that curcumin at 0.3 W/V% was an effective pH changing indicator which changes from orange to red in alkaline conditions. The developed film had an effective UV barrier property together with the enhanced mechanical properties and pH sensing ability and therefore can be used as smart packaging material. Further research is in the progress to incorporate the antimicrobial agent of the natural origin in the packaging film to bring antibacterial properties to the film

Modulation of N^N′-bidentate chelating pyridyl–pyridylidene amide ligands offers mechanistic insights into Pd-catalysed ethylene/methyl acrylate copolymerisation

The efficient copolymerisation of functionalised olefins with alkenes continues to offer considerable challenges to catalyst design. Based on recent work using palladium complexes containing a dissymmetric NN '-bidentate pyridyl-PYA ligand (PYA = pyridylidene amide), which showed a high propensity to insert methyl acrylate, we have here modified this catalyst structure by inserting shielding groups either into the pyridyl fragment, or the PYA unit, or both to avoid fast beta-hydrogen elimination. While a phenyl substituent at the pyridyl side impedes catalytic activity completely and leads to an off-cycle cyclometallation, the introduction of an ortho-methyl group on the PYA side of the NN '-ligand was more prolific and doubled the catalytic productivity. Mechanistic investigations with this ligand system indicated the stabilisation of a 4-membered metallacycle intermediate at room temperature, which has previously been postulated and detected only at 173 K, but never observed at ambient temperature so far. This intermediate was characterised by solution NMR spectroscopy and rationalises, in part, the formation of alpha,beta-unsaturated esters under catalytic conditions, thus providing useful principles for optimised catalyst design

Creating and curating an archive: Bury St Edmunds and its Anglo-Saxon past

This contribution explores the mechanisms by which the Benedictine foundation of Bury St Edmunds sought to legitimise and preserve their spurious pre-Conquest privileges and holdings throughout the Middle Ages. The archive is extraordinary in terms of the large number of surviving registers and cartularies which contain copies of Anglo-Saxon charters, many of which are wholly or partly in Old English. The essay charts the changing use to which these ancient documents were put in response to threats to the foundation's continued enjoyment of its liberties. The focus throughout the essay is to demonstrate how pragmatic considerations at every stage affects the development of the archive and the ways in which these linguistically challenging texts were presented, re-presented, and represented during the Abbey’s history