Recent developments in semi-active control of magnetorheological materials-based sandwich structures: A review

Magnetorheological (MR) materials are kinds of smart materials whose rheological characteristics are controllable with the application of external magnetic fields. In the last few decades, MR materials are well established as one of the leading smart materials for use in adaptive sandwich structures and systems for salient vibration control. This article reviews the semi-active vibration suppression of flexible structures with smart materials of MR fluids (MRFs) and MR elastomers (MREs). Stiffness and damping characteristics of beams, plates, panels, and shells integrating the core layer of MRFs and MREs are discussed in terms of field-dependent controllability. To keep the integrity of the knowledge, this review includes a study on free and forced vibration characteristics of sandwich structures with fully and various configurations of partial MR treatments, stability analysis of MR sandwich structures under rotating conditions and developments in identifying the optimal locations of MR sandwich structures for better vibration control are also discussed. Further, this article focuses on the role of carbon nanotubes in enhancing the field-dependent stiffness and damping properties of MR materials. A few of the most relevant research articles are reviewed and presented here briefly. </jats:p

Dynamic analysis of laminated composite sandwich beam containing carbon nanotubes reinforced magnetorheological elastomer

In this study, dynamic analysis of three-layered sandwich beam with thin orthotropic skins and multiwall carbon nanotubes reinforced magnetorheological elastomer (MWCNT-MRE) core have been investigated. The laminates are made of glass fiber/epoxy composites with ply orientation of [0/90] s and are prepared using vacuum-assisted hand layup process. Experiments are performed to investigate the vibration characteristics of MWCNT-MRE and MRE sandwich structures by applying the various magnetic field intensities under different end conditions. Further, the laminated composite MWCNT-MRE and MRE sandwich beams are modeled using ABAQUS finite element software and validated through experimental results in terms of natural frequencies. Also, the present finite element model is validated with available literature in terms of natural frequencies. A very good agreement is observed between the results of the experimental method and those extracted from numerical simulation. Also, the influence of applied magnetic field levels, core thickness ratio, ply orientation, and various boundary conditions on the vibration behavior of laminated composite MWCNT-MRE and MRE sandwich beams are analyzed. </jats:p

Biosynthesis Of Silver Nanoparticles Using Rose and Jasmine and Its Anti Diabetic Potential

Introduction: Rose (rosa canina) is one of the flowers that are much in demand by the community because besides being an ornamental flower it can also be used as a cosmetic. Traditional medicinal herbs have seen a rebound in recent years, and as a result, pharmaceutical companies are investing heavily in developing natural medications derived from plants. Aim: To study the Anti-diabetic activity of Rose Jasmine formulation mediated silver nanoparticles. Materials and methods: The anti-diabetic activity was tested by the following inhibition of α-glucosidase at different concentrations of the prepared extract mediated with silver nanoparticles. Result: Using rosa and jasminum extract in the manufacture of silver nanoparticles, the nanoparticles showed remarkable anti-diabetic activity. It was discovered that the herbal effect was less harmful. Rosa jasminum extract of AgNps showed good anti-diabetic efficacy in the BSA assays. Conclusion: Result of this study suggest that biosynthesis of silver nano particle using rose and Jasmine showed its anti diabetic activity</jats:p