The antibacterial activity and antibacterial mechanism of the tea polyphenol liposomes/lysozyme–chitosan gradual sustained release composite coating

To obtain long-lasting preservation materials, the tea polyphenol liposomes (TP-Lips)/lysozyme (LZM)–chitosan (CS) composite coating with the gradual sustained property was prepared by tape casting method. These coatings were characterised, and their physicochemical properties were measured. Meanwhile, the antibacterial mechanisms of coatings were studied using the spoilage bacteria of aquatic products (Shewanella putrefaciens and Pseudomonas fluorescens) as target strains. Compared with CS coating, the incorporation of TP-Lips makes the cracks and granular matter of the coatings increase. Except for the oxygen permeabilities (OP) and carbon dioxide permeabilities (CDP), the rest of the physicochemical properties are decreased, including tensile strength (Ts), elongation at break (EB) and light transmittance (T). Antibacterial mechanisms indicate that TP and LZM have a synergistic antibacterial effect. The slow-release system composed of liposomes and coating prolongs the action time of TP and LZM. Hence, the TP-Lips/LZM-CS coating could be a hopeful material in food preservation field with excellent antibacterial properties.     

Role of Fuel on Cation Disorder in Magnesium Aluminate (MgAl2O4) Spinel Prepared by Combustion Synthesis

Magnesium aluminate spinel (MgAl₂O₄) forms an interesting system having tetrahedral and octahedral voids filled with near similar sized divalent Mg²⁺ and trivalent Al³⁺ cations. Structural disorder (e.g., Mg–Al antisite defects) can be tuned by synthetic conditions. This study reports the evolution of Mg/Al disorder in MgAl₂O₄ prepared by combustion synthesis using different types of fuels. The effect of nature of fuel and the final calcination temperature (600°C–900°C for 9 h) on degree of cation ordering has been investigated combining powder X‐ray (XRD) and neutron (NPD) diffraction. The results indicate very high degree of inversion in the samples crystallized at low annealing temperature, which on further annealing reduces toward the thermodynamically stable values. Raman spectroscopy, probing MgO₄, and AlO₄ tetrahedral bonds, confirmed the results at a local level.     

Hybrid-Trefftz finite element model for antisymmetric laminated composite plates using a high order shear deformation theory

International Journal of Mechanics and Materials in Design - A novel hybrid-Trefftz finite element (HTFE) has been developed for the static analysis of thick and thin antisymmetric cross-ply and...     

Chaos based encryption of quantum images

Multimedia Tools and Applications - Content, be it any form text, image or video, which needs to be sent from one place to another is vulnerable to third party attacks if it is sent without proper...     

From cation flexibility to multifaceted industrial adoptability: a voyage to the resourceful spinel*

ABSTRACT

Signature of cation flexibility associated with the order–disorder structure of three spinel families, namely aluminates (MgAl₂O₄/ZnAl₂O₄), ferrites (NiFe₂O₄/Zn_xNi_{1? x}Fe₂O₄), and titanate (Li₄Ti₅O₁₂) was probed using the X-ray diffraction and Raman spectroscopy. Cation flexibility (also known as antisite defects or (dis)order structural transitions) is a unique feature of many oxide AB₂O₄ spinel systems in which the cations exchange their sites under external influence. This feature generates functionality in many different ways. In some cases, such as ferrites, the flexibility of zinc to occupy tetrahedral sites enhances the magnetic properties, whereas the flexibility of lithium in lithium titanate brings exotic electrochemical feature with zero strain. Similarly, cation flexibility of magnesium and aluminium makes the structure tolerant towards nuclear irradiation. Some such salient features of spinel systems are described highlighting the underlying crystal structures.

Enriched with enormous chemical versatility, order–disorder structure, vacancy, interstitials and mixed-cation occupancy, ‘Spinel is a world in itself’. This is why, exploring its huge accomplishments never gets enough. Ever wonder, where from this versatility stems in! This review endeavours to seek the answer by combining the flexible order–disorder structure, supporting diagnosis tools and tuneable properties of this versatile class: The Spinels.     

Mechanical Characterization of Near-Isotropic Inconel 718 Fabricated by Laser Powder-Bed Fusion

Metallurgical and Materials Transactions A - The characterization of Ni-based superalloy Inconel® 718 fabricated by powder-based laser fusion process was performed to study microstructural...