Effect of γ-irradiation and semiconducting oxide (tio2) on the thermal decomposition of mgc2o4: A comparative study

The simultaneous rising temperature (DTA-TG) technique and the gas evolution method are adopted for studying the thermal decomposition of unirradiated and irradiated MgC₂O₄ and MgC₂O₄ + TiO₂ mixtures. The data are applied to theories of different solid state reaction models and the best fit is obtained for the Avrami-Erofeev mechanism (n=2) suggesting that both the nucleation and growth processes occur at the reactant product interface in a two dimensional chain branching manner. Low irradiation doses decrease the rate of reaction remarkably whereas the reverse phenomenon takes place at higher doses. The n-type semiconducting oxide, TiO₂ (5-40 mol%) enhances the rate of decomposition which increases with increasing concentration of the catalyst. The influence of n -irradiation is explained in the light of defects, dislocations and electron-hole (e^?, h⁺) pairs generated in the lattice, whereas the influence of TiO₂ is understood on the basis of electron transfer process involved in the reaction.     

Influence of γ-irradiation on the non-isothermal decomposition of calcium-gadolinium oxalate

Thermal decomposition of co-precipitated unirradiated and irradiated Ca-Gd oxalate has been studied by adopting differential thermal analysis (DTA) and thermogravimetric (TG) techniques. The reaction occurs through two stages corresponding to the decomposition of gadolinium oxalate (Gd-Ox) followed by that of calcium oxalate (Ca-Ox). The kinetic parameters for both the stages are calculated by using solid state reaction models and Coats-Redfern's equation. The co-precipitation as well as irradiation alter the DTA peak temperatures and the kinetic parameters of Ca-Ox. The decomposition of Gd-Ox follows the two dimensional Contracting area ( R 2 ) mechanism, while that of Ca-Ox follows the Avrami-Erofeev ( A 2 ) mechanism ( n =2), which are also exhibited by the co-precipitated and irradiated samples. Co-precipitation decreases the energy of activation and the pre-exponential factor of the individual components but the reverse phenomenon takes place upon irradiation of the co-precipitate. The mechanisms underlying the phenomena are explored.     

Thermo-hydraulic and entropy generation analysis of recharging microchannel using water-based graphene–silver hybrid nanofluid

Journal of Thermal Analysis and Calorimetry - This work numerically investigates thermo-hydraulic and entropy generation characteristics of water-based graphene–silver (Gr–Ag) hybrid...     

Evaluation of binding performance of bioactive compounds against main protease and mutant model spike receptor binding domain of SARS-CoV-2: Docking,ADMET properties and molecular dynamics simulation study

Phytochemicals present in medicinal plants have a variety of biological activities that help to combat against diseases. As part of efforts to study the binding performance of different phytochemicals derived from different plants like Zingiber officinale, Citrus limon, Syzygiumaromaticum, Ocimum tenuiflorum and Curcumin. We have screened 424 molecules. The binding affinity as well as physicochemical properties of the thebaine, acacetin, indomethacin, crinamineacetate, (S)-1-Piperideine-6-carboxylate, levamisole, melatonin, nicotinicacid, curcumin, methotrimeprazine, omeprazole, and methaqualone phytocompounds were analyzed through computational study. From the molecular docking study we found that, LEU50, ASN72, PRO96, TYR154, GLY170, ALA193, ARG222, and MET274 residues of main protease play a crucial role in binding with ligands. The present study revealed a noticeable interaction of GLY446, SER477, GLY482, THR500 and LEU518 residues with mutant of spike receptor binding domain SARS-CoV-2 protein were observed. Finally, 100 ns molecular dynamics simulation were used to study their dynamic properties as well as conformational flexibility. Free energy landscape analysis was performed of the 6LU7- acacetin and 6Y2E-acacetin systems and spike RBD-acacetin system. From molecular docking study and molecular dynamics study revealed that, the compound acacetin shows promising inhibitor towards both main protease as well as mutant spike RBD of SARS-CoV-2 protein.     

Enhanced dielectric and electrical performance of phosphonic acid-modified tantalum (Ta)-doped potassium sodium niobate (KNaNbO3)-P(VDF-HFP) composites

The European Physical Journal E - We discuss the lateral dynamics of two active force dipoles, which interact with each other via hydrodynamic interactions in a thin fluid layer that is active and...     

Some results on a doubly truncated generalized discrimination measure

Doubly truncated data appear in some applications with survival and astrological data. Analogous to the doubly truncated discrimination measure defined by Misagh and Yari (2012), a generalized discrimination measure between two doubly truncated non-negative random variables is proposed. Several bounds are obtained. It is remarked that the proposed measure can never be equal to a nonzero constant which is independent of the left and right truncated points. The effect of monotone transformations on the proposed measure is discussed. Finally, a simulation study is added to provide the estimates of the proposed discrimination measure.     

Current trends in spinel based modified polymer composite materials for electromagnetic shielding

The present article deals with current trends in spinel based modified polymer composite materials for applications in the field of electromagnetic shielding. The interaction between the various spinel based materials and polymers is an emerging field of studies among various researchers. The thermal stability, electrical conductivity, the bonding between the metal ferrites and the polymer plays an important role in the interaction of electromagnetic radiation. These properties also effect the mechanism of the EM waves for the shielding applications. Considering these all properties, polyaniline appears to be an suitable polymer for electromagnetic shielding applications. Polyaniline composites not only reinforced the properties of spinel materials but also enhanced the dielectric properties of the composite material. When carbon based materials such as graphene, graphene oxide and CNT was added along with spinel material in polyaniline based composite, they accelerate the electrical properties and enhances the shielding applications. In this paper the various synthesis methods, fabrication methods of polyaniline, and the properties of polyaniline based composites have been discussed. In addition, the various salient features and futuristic challenges of polyaniline based composite materials for EMI shielding applications were attempted to make a well equipped material for radar absorption.     

Enhanced dielectric properties of polyethylene glycol (PEG) modified BaTiO<Subscript>3</Subscript> (BT)-poly(vinylidene fluoride) (PVDF) composites

To improve the compatibility between the ceramic particle and polymer matrix, the surface modifier polyethylene glycol (PEG) was used for the modification of BaTiO₃ (BT) particles as fillers in the poly(vinylidene fluoride) (PVDF) matrix via solution casting techniques. The structural analysis of the composite characterized by X-ray diffraction confirms the tetragonal structure. The results showed that the PEG modified BT-PVDF composites had a higher dielectric constant (≈192) and relatively lower dielectric loss value at 1000 Hz. The Nyquist plot suggests the contribution of only bulk effect present in the composites. The AC electrical conductivity studies obey Jonscher’s universal power law by fitting AC conductivity data which reveals the potential utility of the composites for ideal capacitor and microscopic reasons for this improvement were presented. Furthermore, the remnant polarization was significantly improved and maximum polarization was observed for PEG modified BT-PVDF composites.     

Computational efforts to identify natural occurring compounds from phyllanthus niruri that target hepatitis B viral infections: DFT,docking and dynamics simulation study

Hepatitis B virus (HBV) is an enveloped hepatotropic virus responsible for nucleic acids replication. It causes chronic infection. Depending on the strain, mutations in the core protein of chronic hepatitis B virus (HBV) infections occur. Medicinal plants, the backbone of traditional medicine, are a potential source of lead molecules in drug discovery due to extensive pharmacological studies. In this study, we have screened twenty-nine phytochemicals. The ADME and drug-likeness of these phytochemicals were investigated. After screening, the binding affinity of ten phytochemicals was studied through molecular docking. Simulation studies were carried out for 100 ns to analyze the properties of RMSD, Rg, RMSF, average hydrogen bond number and SASA of hepatitis B virus capsid protein. As per the docking results phyllanthosterol, may be used as a potential inhibitors against HBV. The simulations findings revealed that, in case of mutant protein, the flexibility nature decreases as compared to wildtype protein. Our results may provide useful information for drug design and to lead the identification of novel inhibitor for hepatotropic viral infection.     

A continuum based modelling approach for adhesively bonded piezo-transducers for EMI technique

In the electro-mechanical impedance (EMI) technique, which is based on induced strain actuation through piezoelectric ceramic (PZT) patch, the knowledge of shear stress distribution in the adhesive bond layer between the patch and the host structure is very pertinent for reliable health monitoring of structures. The analytical derivation of continuum based shear lag model covered in this paper aims to provide an improved and more accurate model for shear force interaction between the host structure and the PZT patch (assumed square for simplicity) through the adhesive bond layer, taking care of all the piezo, structural and adhesive effects rigorously and simultaneously. Further, it eliminates the hassle of determining the equivalent impedance of the structure and the actuator separately, as required in the previous models, which was approximate in nature. The results are compared with the previous models to highlight the higher accuracy of the new approach. Based on the new model, a continuum based interaction term has been derived for quantification of the shear lag and inertia effects.