Applied Mechanics and Materials Vol. 908

Abstract: Rare-earth-based nanocomposites are currently attracting extensive research interest in biology, medicine, physics, chemistry and material science owing to their optical, electrical and electronic properties, their stability and novel applications. Rare-earth based nanomaterials, especially rare earth oxides (Yttrium oxide, Gadolinium oxide, lanthanum oxide, cerium dioxide, etc.) have fascinated people's devotion owing to their good environmentally friendly and redox properties characteristics. Rare-earth based nanomaterials with exceptional electrochemical properties can be attained by simple, low-cost, environmentally friendly approaches such as hydrothermal/solvothermal method, electrodeposition method, atomic layer deposition method, etc. The electrochemical and microstructures properties of the samples were characterized by X-ray diffraction, scanning electron microscopy, galvanostatic charge/discharge cycling, potentiostatic electrochemical impedance spectroscopy and cyclic voltammetry, in this review, we present a wide-ranging explanation of synthesis methods, morphology and electrochemical performance of numerous rare-earth based nanomaterials used in supercapacitors. We present in this review a brief overview of the recent and general progresses in their functionalization and synthesis.

Abstract: A copper metal organic frame work (MOF) is synthesized by taking equimolar terephthalic acid and copper nitrate and its MOF /nanocomposite are fabricated with silver oxide and reduced graphene oxide nanocompounds. It is characterized by XRD, UV-Vis spectroscopy and FTIR. The band gap of the MOF/ nanocomposites is reduced when compare to individuals. This reduction of band gap is due to a slight change in their individual band gaps or lattice distortion hybridization leads to shifting of the energy level.

Abstract: In recent pandemic period it becomes very important to provide a detection technique which will offer high sensitivity, selectivity with low limit of detection. Optical biosensors provide an intriguing path for continuous and rapid detection of target analyte in order to enhance health outcomes. In these recent years nanomaterials have been largely focused in order to design highly efficient biosensors. As Noble metal nanoparticles are well known for their unique properties like plasmonic property, superconductivity and biocompatibility, were extensively used in different scientific field. Noble metal like gold, silver and platinum nanoparticles are used in designing different biosensors. These biosensors were widely used in virus detection of different respiratory related health problems like COVID-19. In this mini review we addressed the optical biosensors fabricated by using noble metal nanomaterials which are used in rapid detection with highly sensitive and selective detection methods with low Limit of detection in recent pandemic period.

Abstract: One of the most often credited materials for opening up new possibilities in the creation of next-generation biosensors is graphene oxide (GO). GO has good water dispersibility, biocompatibility, and high affinity for specific biomolecules due to the coexistence of hydrophobic domains from pristine graphite structure and hydrophilic oxygen containing functional groups, as well as properties of graphene itself that are partly dependent on preparation methods. The high signal output and a strong potential for rapid industrial growth rate, graphene-based materials, such as graphene oxide (GO), are receiving substantial interest in bio sensing applications. Some of graphene's most enticing qualities are its superior conductivity and mechanical capabilities (such as toughness and elasticity), as well as its high reactivity to chemical compounds. The existence of waves on the surface (natural or created) is another property/variable that has immense potential if properly utilized. Single cell detection can be performed by optical biosensors based on graphene. The present state of knowledge about the use of graphene for bio sensing is reviewed in this article. We briefly cover the use of graphene for bio sensing applications in general, with a focus on wearable graphene-based biosensors. The intrinsic graphene ripples and their impact on graphene bio sensing capabilities are extensively examined.

Abstract: Neurotransmitters are synapses transmitting messengers that are vital towards human wellness. Any abnormality in their behaviour can lead to huge psychological ailments such as Parkinson's, Alzheimer's, and Schizophrenia. During diagnosing and assessing mental diseases, it is critical to discover distinct measures of different neurotransmitters present. A combination of nanomaterials, proteins, and polymers are employed to create suitable detecting and sensing component systems. Electrochemical detection has been widely employed for in-vivo detection, with FSCV emerging as the most promising technology to date due to advantages such as high sensitivities, simple device structure, and facile downsizing. Excessive background noise and signal, restricted target selectivity, declination with time, and the device fouling are all issues that in-vivo electrochemical neurotransmitter indications encounter. Nanomaterials have sparked a tremendous focus in recent years owing to their diverse properties. CPEs are amongst the safest and most ecologically beneficial electrodes with a vast scope of applications due to their incredibly simple and rapid manufacturing method, lower back - ground current, relatively inexpensive, adaptability to numerous modifiers and modifying techniques, so on and so forth.

Abstract: During the last two decades, over more than five million research papers (articles, reviews, communications etc.) were published on nanocomposite materials. Most of them are excellent contributions that already mingle the readers’ and researchers’ interests; thus gaining many citations. This mini-review is focused on advancement in next-generation nanocomposite materials based on optical and sensing applications; and their practical execution. Some recent novel developments will be highlighted and future trends will be discussed. Nowadays, nanocomposite has ended up one of the most popular materials with potential usage in various scope, including packaging, automotive and aerospace industry, batteries with higher power output, flexible batteries, making lightweight sensors, in photocatalysis and making tumours easier to look at and to eliminate. New materials, viz. designed polymers, metal oxides, alloys, chalcogenides, nanostructured and hierarchical carbons, regularly induced researchers and engineers; to test and compare them with existing sensors of multifarious sorts. Nanocomposites not only offers’ the new technology and business opportunities in all sectors of the industry but also it tender innovations and new openings for all divisions.

Abstract: There is a lack of information on the magnetic properties of particles of such materials as powder magnetic (modified by inclusions of magnetite and maghemite) carbon sorbents intended for water purification from various kinds of impurities and, what is especially important, allowing to perform the prompt isolation of the spent sorbent – by magnetic separation. The data on the magnetic susceptibility χ of the particles of these sorbents, found by the developed experimental calculation method based on the concept of the corresponding magnetometry of a moderately rarefied dispersed sample with a dispersed phase of the particles under study, are presented. Experimental dependences of the magnetic susceptibility of <χ>of a dispersed sample on the volume fraction γ of controlled particles in it have been obtained - for different values ​​of the magnetic field strength H in the range from 22 to 61 kA/m, i.e. in the postextremal region for the susceptibility. In addition to the necessary assessment of their linear, located at γ ≤ 0.15-0.2, sections, this also made it possible to find and phenomenologically describe the field dependences of the generalized data of the reduced susceptibility of <χ>/γ, i.e. data χ: in the form of an inverse power function with a power of 0.7 ... 0.8 at H.

Abstract: Along with the increase in watermelon production, the amount of watermelon rind waste increased. The total mass of fruit rind in a watermelon reaches around 30 percent and this fruit rind can increase the quantity of organic waste in Indonesia. The outer portion of the watermelon rind has a green layer containing a large amount of anthocyanin and a white layer containing flavonoids. In this study, the extract of watermelon rind containing anthocyanins and flavonoids was protected from damaging conditions using the ionic gelation encapsulation method. Chitosan (CN) was used as a natural polymer in this encapsulation method and sodium tripolyphosphate (TPP) was used as an ionic crosslinking agent. The total of flavonols content (TF), microstructure test, in vitro releasing test, and shelf life of microcapsules were observed in the various ratio between watermelon rind and the solvent. From the process, can be concluded that higher watermelon skin levels will produce the most flavonoid microcapsules (70g/35 mL). At 70g/35 mL or 2:1 g/mL watermelon skin levels give the best flavonoid release test results, especially if it will be applied to the pharmaceutical industry, which follows a controlled release method.

Abstract: Pollution by textile dyes on waterbodies is an issue for both human health and the environment. To remove/degrade dyes, many approaches (coagulation, membrane separation, and adsorption) have been investigated. However, the use of semiconductor-assisted materials in conjunction with sustainable solar energy has emerged as a possible solution to the problem. Although single component photocatalysts have been tested, composites of semiconductor materials are being employed owing to their low efficiency and stability due to the high recombination rate electron-hole pair and inefficient visible light absorption. By combining two or more semiconductor components, semiconductor heterojunction systems are created. Overall stability is increased by the synergistic impact of their features, such as adsorption and better charge carrier movement. This paper discusses current advances in advanced nanocomposite materials utilized as photocatalysts, as well as the utilization of heterojunctions, crystallinity, and doping to improve photocatalytic characteristics. The conclusion includes a summary, research gaps, and a forecast for the future. This study will aid in the development of efficient heterostructure photodegradation systems by providing a comprehensive appraisal of recent advances in demonstrating effective nanocomposites for photodegradation of Rhodamine B dye under ideal circumstances.