Advanced Materials Letters

Abstract COVID-19 risk spread rapidly with several clinical manifestations and public health challenges. Research and innovation in advanced materials should be focused on solving critical problems associated with diagnosis, treatment and control models. Important challenges of COVID-19 public health system indicated to need of solutions based on cost, quality and universal availability in sustainable model. Standard healthcare models can be achieved by advanced technology of Artificial intelligence, IoT, Database analytics and advanced materials more effectively for mass community. Next-generation (“smart”) materials have capacity to contribute to theranostics models in better way with high accuracy in terms of performance and reliability. In summary, engineered nanoparticles and advanced technologies have translational potential. Being public health professionals, technologist and materials researchers involved in the prognosis research should develop certain priorities for the society.

Abstract The application of flax fiber is vast in the various fields in the world, the well-known in the area of as textiles many of the countries they used the flax fiber mixture with linen, traditionally used for making of bed sheets, underclothes and table linen. The specific properties of flax fiber responsible for the potential platform to next-generation structural applications in automobile and other consumer works. Due to its mechanical properties, flax fiber composites possess good strength and durability. In this review paper, the various proportion on evaluation of work done to know about the amount of research undergone with flax fiber composite in various fields. From this review paper, the utilization of flax fiber has gap in variety of applications in various fields. To identify the research gap and its utilization, quantum of work to be done in the all of the areas was analyzed in that 36% of work done on mechanical property, 30% in novel performance work like simulation and model analysis, 18% of work going on marine, aeronautical related applications and only 16% work carried out in structural related applications using flax fiber composite, flax fiber composite products are potentially used because of their lighter weight and lower cost. Most of the automobile components are replaced by flax fiber composite, these composite components are sound in the capability to reduce the weight for fuel efficiency. Other developing market applications such as tiles, marine piers and flower pots are now a day manufactured from flax fiber composite. In the future, the flax fiber will reduce the utilization of synthetic fiber, by producing an eco-friendly environment in all type of products, wherever replacement is possible with some synergic property.

Abstract Multilayer stacks constituted by carbon fiber reinforced polymers (CFRPs) and titanium (Ti) alloys are advanced structural materials being extensively used in the modern aerospace industry in view of their superior properties and functionality. Prior to the final industrial applications, CFRP/Ti stacks have to be machined into desired shapes with qualified surface quality. However, these multilayer materials possess rather poor machinability due to the disparate natures of constituted phases. The present review aims to report on the recent advancements and achievements in the machining of CFRP/Ti stacks by emphasizing the key challenges and difficulties faced by the manufacturing community to achieve the high-quality drilling of the stack materials. A careful discussion on the machinability aspects of the aerospace-grade stacks in terms of chip separation mechanisms, cutting forces, machining temperatures and surface quality attributes was made following a detailed literature survey. The work summarizes the current research progress in the subject area of composite/titanium machining and highlights the future research directions. It will help both academic scholars and industrial engineers specializing in the fields of machining multilayer composite-metallic stacks.  

Abstract The objective of this paper is to investigate the magnetic nature of Dilute Magnetic Dielectrics (DMD) under variation of external magnetic field. The said variation is studied over developed nano sized Gadolinium Nickel Sulfide complex, Cobalt Sulfide, Nickel Sulfide and Titanium Sulfide as a DMD system. The observed experimental field variation of the effective magnetic permeability is the analyzed results of optical experiment. The experiment records the variation of Brewster angle of incident polarized LASER beam from the surface of developed DMD specimen with applied out of plane external magnetic field. The relative permittivity and relative magnetic permeability were estimated by following the electromagnetic theory. The overall results obtained are found to be holding a good agreement between theory and experiment.

Abstract Solid Polymer Electrolyte (SPE) has great potential in replacing liquid electrolytes. The SPE has many advantages such as high thermal stability, good flexibility, and non-flammable. One of the polymers that can be used is chitosan biopolymer from shrimp skin extraction. Generally, polymers are isolators and have low ionic conductivity, so that modification to the structure of chitosan is needed to increase the ionic conductivity. One way to modify the chitosan structure is by plasticizer addition. In this study the addition of sorbitol plasticizer was carried out with a variation between 0, 20, 40, 60 and 80 (in weight percent) which is called as CA for pure chitosan, CA1, CA2, CA3, CA4 and CA5 respectively. The synthesis of chitosan electrolyte film was prepared by casting method. Then qualitative and quantitative analysis was carried out by using X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and mechanical properties. Optimal composition was obtained by 40% (in weight percent) sorbitol addition with a conductivity of 3.74 ´ 10 -5 S.cm -1 . XRD measurement shows more amorphous polymers with more sorbitol addition. The sorbitol addition also increases the tensile strength, elongation and Young modulus of film flexibility become 52.3%, and 158.3MPa and 19.8MPa, respectively.

Abstract Thin film with immobilized particulates of Cobalt oxide (Co3O4) has been synthesized by Pulsed Laser Deposition (PLD) technique followed by thermal treatment in air. Surface morphology of the Co3O4 films was examined using Field Emission Scanning Electron Microscopy (FESEM). Crystalline structure of Co3O4 films was investigated by X-ray Diffraction (XRD) and Raman spectroscopy was used to confirm the presence of Co3O4 phase on the surface. Efficient catalytic performance was obtained with these films for hydrolysis in Sodium Borohydride (NaBH4). A maximum hydrogen generation rate of ~5100 mL min -1 g -1 of catalyst was recorded at a temperature of 305 K with calculated activation energy of 62.96 kJ/mol. Good catalytic activity could be attributed to nanostructures of the films formed following heat treatment consisting of densely packed nanoparticles (NPs) which act as active catalytic centers, and the immobilized nature of the particles on the surface of the films. These catalyst films showed no major loss of activity even after five cycles of use allowing at the same time an advantage of easy separation from the solution. Our results thus demonstrate good catalytic performance and reusability of such PLD deposited Co3O4 nanostructured films towards hydrogen production by hydrolysis of NaBH4.

Abstract Thermodynamic and structural properties of compound forming binary liquid copper tin alloy at 1400K have been well analyzed as a function of concentration by considering Cu3Sn complex by using Quasi lattice model. The mixing behavior of the alloy is studied in detailed by giving more emphasis on the interaction energy parameters between neighboring atoms of the alloy. The study provides the information of moderately interacting as well as ordering nature on the entire range of concentration of the liquid alloy. Similarly transport and surface properties (viscosity surface tension) of the liquid have also been studied under statistical models; Budai-Banko-Kaptay model and Butler's approach. The computed theoretical thermodynamic data of 1400K are in good agreement with the corresponding experimental data. The viscosities and surface tension of the alloys computed predicts noticeable negative derivation from ideal case and these increase with increase in copper atoms in the alloy.

Abstract The variation of thermoelectric properties of Zr₂O₃-In₂O₃-ZnO film system is reported here. The films are fabricated in a chemical composition satisfies the relation Zr_xIn_xZn_1-xO_1-δ, (0.01≥ x ≥ 0.04), through spray pyrolysis technique. XRD analysis shows a switching of preferred crystal growth orientation from (002) to (100) and (101) planes as x increases.  The quasi spherical surface morphology was improved on the addition of the cations. A maximum Seebeck coefficient of -159 µV/K was obtained for x=0.01 at 400K. The decrease in the Seebeck coefficient for higher x values is explained with simplified broadband model. At elevated temperature power factor increased considerably up to 2.33 X 10^-4 Wm^-1K^-2 for x=0.03 which was attributed to decrease in sheet resistance at high temperature.

Abstract The electronic properties of the ChalcopyritesAgFeS₂, AgFeSe₂ and AgFeTe₂ have been investigated using the pseudopotential method within the density functional theory (DFT). The LDA+U technique and the projector augmented waves (PAW) were used for the electronic band structure calculations, while the norm-conserving pseudopotentials were used for the structure optimization. The calculated results showed that AgFeS₂, AgFeSe₂ and AgFeTe₂ are semiconductors with energy bandgap values of 3.33 eV, 0.05 eV and 1.30 eV respectively. The transition points in the band structure were all notable because of the narrowness of the bands about the Fermi level. The total density of states and their corresponding partial density of states were also computed.