Browse Topic: Chemicals
In physical chemistry, time-resolved spectroscopy is the study of dynamic processes in materials or chemical compounds. Within this field, various techniques including transient absorption spectroscopy are used to study the mechanistic and kinetic details of chemical processes that occur within just a few picoseconds to a femtosecond — the equivalent of one millionth of one billionth of a second
University of Waterloo Chemical Engineering Researcher Dr. Elisabeth Prince teamed up with researchers from the University of Toronto and Duke University to design the synthetic material made using cellulose nanocrystals, which are derived from wood pulp. The material is engineered to replicate the fibrous nanostructures and properties of human tissues, thereby recreating its unique biomechanical properties
Silicone elastomers have become a vital material in the medical device industry due to their unique properties, including biocompatibility, durability and chemical inertness. Silicone materials are categorized based on their unvulcanized consistency, which significantly affects their processability and their physical properties. This article compares high consistency silicone rubbers (HCRs), liquid silicone rubbers (LSRs), and low consistency elastomers (LCEs), analyzing their characteristics and the implications in selecting each during different phases in the development of silicone medical devices
Nylon, Teflon, Kevlar. These are just a few familiar polymers — large-molecule chemical compounds — that have changed the world. From Teflon-coated frying pans to 3D printing, polymers are vital to creating the systems that make the world function better
Researchers at Tufts School of Engineering have developed a method to detect bacteria, toxins, and dangerous chemicals in the environment with a biopolymer sensor that can be printed like ink on a wide range of materials — including wearables
Unlike glass, which is infinitely recyclable, plastic recycling is challenging and expensive because of the material’s complex molecular structure designed for specific needs. New research from the lab of Giannis Mpoumpakis, Associate Professor of Chemical and Petroleum Engineering at the University of Pittsburgh, focuses on optimizing a promising technology called pyrolysis, which can chemically recycle waste plastics into more valuable chemicals
A unique wristwatch contains multiple modules, including a sensor array, a microfluidic chip, signal processing, and a data display system to monitor chemicals in human sweat. It can continuously and accurately monitor the levels of potassium (K+), sodium (Na+), and calcium (Ca2+) ions
This specification covers a rust removing compound in the form of a solid, generally powdered, to be dissolved in water, and heated
A commonplace chemical used in water treatment facilities has been repurposed for large-scale energy storage in a new battery design by researchers at the Department of Energy’s Pacific Northwest National Laboratory. The design provides a pathway to a safe, economical, water-based, flow battery made with Earth-abundant materials. It provides another pathway in the quest to incorporate intermittent energy sources such as wind and solar energy into the nation’s electric grid
Remember that party where you were swinging glow sticks above your head or wearing them as necklaces? Fun times, right? Science times, too. Turns out those fun party favors are now being used by a University of Houston researcher to identify emerging biothreats for the United States Navy
Recycling of advanced composites made from carbon fibers in epoxy resins is required for two primary reasons. First, the energy necessary to produce carbon fibers is very high and therefore reusing these fibers could greatly reduce the lifecycle energy of components which use them. Second, if the material is allowed to break down in the environment, it will contribute to the growing presence of microplastics and other synthetic pollutants. Currently, recycling and safe methods of disposal typically do not aim for full circularity, but rather separate fibers for successive downcycling while combusting the matrix in a clean burning process. Breakdown of the matrix, without damaging the carbon fibers, can be achieved by pyrolysis, fluidized bed processes, or chemical solvolysis. The major challenge is to align fibers into unidirectional tows of real value in high-performance composites
Robots and cameras of the future could be made of liquid crystals, thanks to a new discovery that significantly expands the potential of the chemicals already common in computer displays and digital watches. The findings are a simple and inexpensive way to manipulate the molecular properties of liquid crystals with light exposure
Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have invented and patented a new cathode material that replaces lithium ions with sodium and would be significantly cheaper. The cathode is one of the main parts of any battery. It is the site of the chemical reaction that creates the flow of electricity that propels a vehicle
In 1941, the SAE Iron and Steel Division, in collaboration with the American Iron and Steel Institute (AISI), made a major change in the method of expressing composition ranges for the SAE steels. The plan, as now applied, is based in general on narrower cast or heat analysis ranges plus certain product analysis allowances on individual samples, in place of the fixed ranges and limits without tolerances formerly provided for carbon and other elements in SAE steels. For years the variety of chemical compositions of steel has been a matter of concern in the steel industry. It was recognized that production of fewer grades of steel could result in improved deliveries and provide a better opportunity to achieve advances in technology, manufacturing practices, and quality, and thus develop more fully the possibilities of application inherent in those grades. Comprehensive and impartial studies were directed toward determining which of the many grades being specified were the ones in most
The aim of this study is to examine the effects of chemical treatments on the performance of composites that are reinforced with natural fibres. Natural fibres have several advantages, such as low density, low cost, and environmental friendliness, as they can be biodegraded or recycled. However, natural fibre composites also have some limitations, such as their poor compatibility with the matrix material and the reinforcement material. This leads to weak interfacial bonding and poor mechanical properties. Another problem with natural fibres is that they absorb more moisture than other materials, which can affect their dimensional stability and durability. Therefore, this research compares the compatibility of different chemical treatments that can modify the surface properties of natural fibres and improve their adhesion with the matrix and reinforcement
A series of buzzing “loop-currents” could explain a recently discovered, never-before-seen phenomenon in a type of quantum material. The quantum material is known by the chemical formula Mn 3Si2Te6, but it’s safe to call it “honeycomb” because its manganese and tellurium atoms form a network of interlocking octahedra that resembles a beehive
In the quest for sustainable materials for automotive interior trim, jute fiber is gaining traction due to its characteristics, which align with other renowned natural fibers. This study aimed to assess the efficacy of sodium bicarbonate as a treatment for jute fibers in comparison to conventional alkaline treatments. Both treated and untreated fibers were examined. Results showed that alkali-processed fibers demonstrated enhanced crystallization, thermal resistance, and surface quality relative to untreated ones. Specifically, alkali-treated jute fibers exhibited a degradation onset at 261.23°C, while those treated with sodium bicarbonate began degrading at 246.32°C. Untreated fibers had a degradation onset at 239.25°C. Although both treatments improved the thermal stability of the fiber, sodium bicarbonate processing, while beneficial, was slightly less effective than the traditional alkaline method. Overall, the research underscores the potential of sodium bicarbonate as an
This specification covers one type of carpet cleaner in the form of a liquid
This specification covers a procedure for revealing the macrostructure and microstructure of titanium alloys
Two-dimensional transition metal dichalcogenides (2D-TMDs) have been proposed as novel optoelectronic materials for space applications due to their relatively light weight. MoS2 has been shown to have excellent semiconducting and photonic properties. Here, we report the effect of gamma irradiation on the structural and optical properties of a monolayer of MoS2. Louisiana State University, Baton Rouge, Louisiana Graphene is a two-dimensional carbon material made of carbon by covalent bonds, where carbon atoms are arranged in a honeycomb lattice. Graphene has promising electronic and mechanical properties. There are many processes available for the formation of the graphene. CVD (Chemical Vapor Deposition) process for the formation of graphene over the metal surface is most compatible. Graphene is being investigated for its application in space electronics. In space, there are many irradiation particles and waves like x-rays, gamma rays, alpha particles, and beta particles. Single
Cornell researchers have combined soft microactuators with high-energy-density chemical fuel to create an insect-scale quadrupedal robot that is powered by combustion and can outrace, outlift, outflex, and outleap its electric-driven competitors
Epoxy polymers are widely used in various industries, e.g., as coatings, adhesives, and for lightweight construction due to their unique properties such as high strength, chemical resistance, and adhesion to various surfaces. Therefore, one of the most prominent applications is their use as matrix material in fiber-reinforced composites, which are heavily employed in the aerospace sector. However, the disposal of epoxy polymers and composites thereof has become a significant concern due to their recalcitrant nature and the adverse environmental effects caused by traditional recycling methods
Composites are especially important for the development and implementation of sustainable technologies such as wind power, energy-efficient aircrafts, and electric cars. Despite their advantages, their non-biodegradability raises challenges for the recycling of polymer and composites in particular. University of Hamburg, Hamburg, Germany Epoxy polymers are widely used in various industries, e.g., as coatings, adhesives, and for lightweight construction due to their unique properties such as high strength, chemical resistance, and adhesion to various surfaces. Therefore, one of the most prominent applications is their use as matrix material in fiber-reinforced composites, which are heavily employed in the aerospace sector. However, the disposal of epoxy polymers and composites thereof has become a significant concern due to their recalcitrant nature and the adverse environmental effects caused by traditional recycling methods. In this context, the overall production of plastic waste is
Graphene is a two-dimensional carbon material made of carbon by covalent bonds, where carbon atoms are arranged in a honeycomb lattice. Graphene has promising electronic and mechanical properties. There are many processes available for the formation of the graphene. CVD (Chemical Vapor Deposition) process for the formation of graphene over the metal surface is most compatible. Graphene is being investigated for its application in space electronics. In space, there are many irradiation particles and waves like x-rays, gamma rays, alpha particles, and beta particles. Single particle like neutron can create single event upset in electronic devices. Graphene can work as a radiation shielding material. Graphene-metal, graphene and epsilon near zero metamaterials structure can be used for electromagnetic wave absorbent
In today's world, there is an increasing emphasis on the responsible use of fiber reinforced materials in the automobile applications, construction of buildings, machinery, and appliances as these materials are effectively reused, recycled, or disposed with minimum impact on the environment. As such, it has become mandatory to incorporate sustainable, environmental friendly and green concepts in the development of new materials and processes. The primary objective of this study is to manufacture composites using fibers obtained from Thespesia Lampas plants, which are known for their soft, long fibers that are commonly used in various domestic products. The composites are made by combining these fibers with a general purpose polyisocyanurate resin, and their potential applications in both domestic and commercial products are explored. To evaluate the properties of these composites, tests are conducted for tensile strength, flexure, and water absorption. The laminates are fabricated
Researchers developed a chemical sensing chip that could lead to handheld devices that detect trace chemicals — everything from illicit drugs to pollution — as quickly as a breathalyzer identifies alcohol. It also may have uses in food safety monitoring, anti-counterfeiting, and other fields where trace chemicals are analyzed
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