Application of Carbon Aerogels in Lithium-Air Batteries
One of the main challenges with today’s batteries is their relatively low volumetric and specific capacities. The highest specific capacity can be achieved with lithium-air batteries, which use metallic lithium as the anode and typically some form of porous carbon as the cathode. To enhance performance, aerogels—among the world’s lightest solid materials—are ideal candidates for cathodes. Resorcinol-formaldehyde (RF)-based carbon aerogels, for example, serve this purpose well. In my work, I utilized two types of carbon aerogels as cathode materials: one derived from pyrolyzed resorcinol-formaldehyde polymer and the other a graphene-oxide-modified version of this carbon gel. I integrated the carbon aerogels I had pyrolyzed into lithium-air batteries to improve the cell’s performance, energy density, and capacity compared to cells using activated carbon. In my research, I examined the pore structure and surface properties of these materials in aqueous media using NMR (nuclear magnetic resonance) relaxometry and cryoporometry, exploring their impact on battery efficiency. I found that the graphene-oxide-containing sample's pores filled with water in a layered manner, indicating a more hydrophilic surface, which suggests a denser arrangement of oxygen-containing functional groups compared to the unmodified carbon aerogel. The pore sizes were reduced after adding graphene oxide, resulting in an increased specific surface area for the sample. Incorporating the reduced graphene-oxide-containing carbon aerogel enabled the creation of a more efficient, higher-capacity battery than with the RF carbon aerogel. This improved performance is likely due to the aerogel’s higher oxygen content and altered morphology. The increased oxygen content provides more active sites for oxygen reduction, meaning that a greater specific power output can be obtained from the battery.
Mattress Ventilation System
One of the worldwide hidden problems with lack of attention is Bedsores. Simply, These are ulcers, that happen on the areas of the skin that are under pressure while lying on the bed for a prolonged time. This can be infected to anyone in the world. The common group who face these bed sores are..... •Elderly patients, •Spinal cord injury patients, •Stroke patients, •Coma patients, •People who have faced accidents Bed sores develop when the blood supply is cut off for more than 2-3 hours to the skin, (Position changing time depends on the patient's condition) The continuous pressure is the cause for that and also the temperature generated between the skin and the bed surface increases the metabolism of the tissues. When the skin temperature increases by 1°C, the risk of bed sores increases approximately 14 times. So, The skin temperature in the range of 29.4°C to 37.1°C is correlated with the tissue damage score. Not only that shearing and moisture are the other considerable factors for this problem. This infection has 4 stages. Sometimes in the 4th stage of the bed sores can cause death.
A Study on Hybrid Electromechanical Actuators
An actuator [7,22,28,29] is a motion control mechanism. Depending on the type of actuator, it can convert one type of energy (e.g. chemical, electromagnetic, thermal) into mechanical energy. The field that laid the foundations for the realization of actuators is the field of electromechanics, whose evolution was common with that of actuators. Thus, a periodization of the electromechanics paradigm includes 3 major stages [7,6,25,28,29]: I.1830-1950 Old electromechanics. It is the period when the development of electric cars is significant, which imposed the appearance of classical or primary electromechanical drives. It was a generous nineteenth century, dominated by the scientific results of the triumvirate: Michel Faraday (initiator of fundamental empirical experiments in the history of electricity; the law of induction, of the principle of electric motor, of the magnetic circuit, initiator of electro-chemistry), James Clerk Maxwell, (the genius theorist who put into mathematical form the equations of electric and magnetic fields, as well as the connection between them), and Werner Siemens (engineer and capitalist genius manager who managed to exploit and validate the relationship research-technology-economic development), triumvirate that can be disputed in the sense that other scientists also made outstanding contributions to the history of electricity: Edison, Ampere, Ohm (to name but a few who do not exhaust a significant list). Industrial production of electric machines also appeared and the first signs that will announce the emergence of electromechanical actuators as a basis for military applications. II.1950-1970, Traditional electromechanics, in which electrical power drives appear, a theoretical and experimental development on the emergence of new material and electromechanical principles. Much military research (such as missile control or ship and torpedo control) influences and produces the transfer of applications in ordinary life, including the actuator subfield. III. 1970-2020, Avant-garde electromechanics, representing according to Thomas Kuhn's theory, a paradigm forcing [30]. It is worth noting the contributions of the new scientific revolution. - Specific technologies of miniaturization, by material deposition. - Elastomeric polymeric materials with the help of which it was possible to make electrostrictive actuators, - Very special means of investigation, mainly the development of microscopy, - Gradient of applications in the field of medical engineering, with outstanding contributions both in investigation and microsurgery, applications of actuators in biological micropumps, etc. [25,27,28,29].