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Topic Review
Magnesium Forging
Interest in magnesium alloys and their applications has risen in recent years. This trend is mainly evident in casting applications, but wrought alloys are also increasingly coming into focus. Among the most common forming processes, forging is a promising candidate for the industrial production of magnesium wrought products. This overview is intended to give a general introduction into the forging of magnesium alloys and to help in the practical realization of forged products. The basics of magnesium forging practice are described and possible problems as well as material properties are discussed.
  • 2.7K
  • 10 Nov 2020
Topic Review
Mars Oxygen ISRU Experiment
The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) is a technology demonstration on the NASA Mars 2020 rover Perseverance investigating the production of oxygen on Mars. On April 20, 2021, MOXIE produced oxygen from carbon dioxide in the Martian atmosphere by using solid oxide electrolysis. This was the first experimental extraction of a natural resource from another planet for human use. The technology may be scaled up for use in a human mission to the planet to provide breathable oxygen, oxidizer, and propellant; water may also be produced by combining the produced oxygen with hydrogen. The experiment was a collaboration between the Massachusetts Institute of Technology, the Haystack Observatory, the NASA/Caltech Jet Propulsion Laboratory, and other institutions.
  • 2.6K
  • 28 Nov 2022
Topic Review
Fundamentals of Water-Splitting Reaction
A viable energy source, hydrogen has the advantages of clean energy, high conversion efficiency, and environmental friendliness. One of the possible routes for the generation of hydrogen in this context is the solar water splitting reaction under direct sunlight. To succeed on a commercial basis, though, there remains a very long way to go. 
  • 2.6K
  • 07 Nov 2022
Topic Review
Amphibole
Amphibole (/ˈæmfəboʊl/) is a group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain SiO4 tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Its IMA symbol is Amp. Amphiboles can be green, black, colorless, white, yellow, blue, or brown. The International Mineralogical Association currently classifies amphiboles as a mineral supergroup, within which are two groups and several subgroups.
  • 2.6K
  • 28 Oct 2022
Topic Review
Carbon Fixation
Carbon fixation or сarbon assimilation is the process by which inorganic carbon (particularly in the form of carbon dioxide) is converted to organic compounds by living organisms. The compounds are then used to store energy and as structure for other biomolecules. Carbon is primarily fixed through photosynthesis, but some organisms use a process called chemosynthesis in the absence of sunlight. Organisms that grow by fixing carbon are called autotrophs, which include photoautotrophs (which use sunlight), and lithoautotrophs (which use inorganic oxidation). Heterotrophs are not themselves capable of carbon fixation but are able to grow by consuming the carbon fixed by autotrophs or other heterotrophs. "Fixed carbon", "reduced carbon", and "organic carbon" may all be used interchangeably to refer to various organic compounds.
  • 2.6K
  • 06 Dec 2022
Topic Review
Additive Manufacturing of Soft Materials
The growing demand for wearable devices, soft robotics, and tissue engineering in recent years has led to an increased effort in the field of soft materials. With the advent of personalized devices, the one-shape-fits-all manufacturing methods may soon no longer be the standard for the rapidly increasing market of soft devices. Recent findings have pushed technology and materials in the area of additive manufacturing (AM) as an alternative fabrication method for soft functional devices, taking geometrical designs and functionality to greater heights.
  • 2.6K
  • 02 Sep 2021
Topic Review
Agro-Based Polymers Food Packaging
This entry compiles information on biopolymers and natural bioactive compounds used in the production of bioactive films. Particular emphasis has been given to the methods used for incorporating bioactive compounds into film-forming solutions and their influence on the functional properties of biopolymer films. 
  • 2.6K
  • 13 Nov 2020
Topic Review
Opioid Epidemic
The opioid epidemic or opioids crisis is the rapid increase in the use of prescription and non-prescription opioid drugs in the United States and Canada beginning in the late 1990s and continuing throughout the next two decades. The increase in opioid overdose deaths has been dramatic, and opioids are now responsible for 49,000 of the 72,000 drug overdose deaths overall in the US in 2017. A recent report indicated that the rate of prolong opioid use is increasing globally. Opioids are a diverse class of moderately strong painkillers, including oxycodone (commonly sold under the trade names OxyContin and Percocet), hydrocodone (Vicodin, Norco), and a very strong painkiller, fentanyl, which is synthesized to resemble other opiates such as opium-derived morphine and heroin. The potency and availability of these substances, despite their high risk of addiction and overdose, have made them popular both as medical treatments and as recreational drugs. Due to their sedative effects on the part of the brain which regulates breathing, the respiratory center of the medulla oblongata, opioids in high doses present the potential for respiratory depression, and may cause respiratory failure and death. In a 2015 report, the U.S. Drug Enforcement Administration stated that "overdose deaths, particularly from prescription drugs and heroin, have reached epidemic levels.":iii Nearly half of all opioid overdose deaths in 2016 involved prescription opioids. From 1999 to 2008, overdose death rates, sales, and substance abuse treatment admissions related to opioid pain relievers all increased substantially. By 2015, there were more than 50,000 annual deaths from drug overdose, causing more deaths than either car accidents or guns. Drug overdoses have since become the leading cause of death of Americans under 50, with two-thirds of those deaths from opioids. In 2016, the crisis decreased overall life expectancy of Americans for the second consecutive year. Overall life expectancy fell from 78.7 to 78.6 years. Men were disproportionately more affected due to higher overdose death rates, with life expectancy declining from 76.3 to 76.1 years. Women's life expectancy remained stable at 81.1 years. In 2016, over 64,000 Americans died from overdoses, 21 percent more than the almost 53,000 in 2015. By comparison, the figure was 16,000 in 2010, and 4,000 in 1999. While death rates varied by state, public health experts estimate that nationwide over 500,000 people could die from the epidemic over the next 10 years. In Canada , half of the overdoses were accidental, while a third were intentional. The remainder were unknown. Many of the deaths are from an extremely potent opioid, fentanyl, which is trafficked from Mexico. The epidemic cost the United States an estimated $504 billion in 2015. CDC former director Thomas Frieden said that "America is awash in opioids; urgent action is critical." The crisis has changed moral, social, and cultural resistance to street drug alternatives such as heroin. Many state governors have declared a "state of emergency" to combat the opioid epidemic or undertook other major efforts against it. In July 2017, opioid addiction was cited as the "FDA's biggest crisis". In October 2017, President Donald Trump concurred with his Commission's report and declared the country's opioid crisis a "public health emergency". Federal and state interventions are working on employing health information technology in order to expand the impact of existing drug monitoring programs. Recent research shows promising results in mortality and morbidity reductions when a state integrates drug monitoring programs with health information technologies and shares data through centralized platform.
  • 2.6K
  • 29 Sep 2022
Topic Review
Additive Manufacturing Processes Classification
Additive manufacturing is an important and promising process of manufacturing due to its increasing demand in all industrial sectors, with special relevance in those related to metallic components since it permits the lightening of structures, producing complex geometries with a minimum waste of material. There are different techniques involved in additive manufacturing that must be carefully selected according to the chemical composition of the material and the final requirements.
  • 2.6K
  • 10 Mar 2023
Topic Review
Functional Coatings
Coating materials have gained researchers’ interest, finding applications in different areas such as antimicrobial coatings for biomedical applications, coatings for increasing the shelf-life of commercial products, or coatings for the conservation of cultural heritage artifacts. 
  • 2.6K
  • 21 Sep 2022
Topic Review
Carbon Nanotube Metal Matrix Composites
Carbon nanotube metal matrix composites (CNT-MMC) are an emerging class of new materials that are being developed to take advantage of the high tensile strength and electrical conductivity of carbon nanotube materials. Critical to the realization of CNT-MMC possessing optimal properties in these areas are the development of synthetic techniques that are (a) economically producible, (b) provide for a homogeneous dispersion of nanotubes in the metallic matrix, and (c) lead to strong interfacial adhesion between the metallic matrix and the carbon nanotubes. Since the development of CNT-MMC is still in the research phase, the current focus is primarily on improving these latter two areas.
  • 2.6K
  • 29 Sep 2022
Topic Review
Three Dimensional Printing
The following article introduces technologies that build 3 dimensional (3D) objects by adding layer-upon-layer of material, called also additive manufacturing technologies.  Furthermore most important features supporting the conscious choice of 3D printing methods for applications in micro and nanomanufacturing were covered. The micromanufacturing method covers photopolymerisation based methods such as Stereolithography (SLA), Digital Light Processing (DLP), Liquid Crystal Display – DLP coupled method, Two-Photon Polymerisation (TPP) and Inkjet based methods. Functional photocurable materials, with magnetic, conductive or specific optical applications in the 3D printing processes were also reviewed. 
  • 2.5K
  • 26 Oct 2020
Topic Review
Applications of 3D Printing in Cosmetics
3D printing (3DP) is a manufacturing technology that produces 3D objects from a design file using layer-by-layer deposition of material. It has already found applications in the healthcare and pharmaceutical industries. There are potential uses for 3DP in the cosmetic field. 
  • 2.5K
  • 22 Nov 2022
Topic Review
Agouti (Gene)
The agouti gene encodes the agouti-signaling protein (ASIP), responsible for the distribution of melanin pigment in mammals. Agouti interacts with the melanocortin 1 receptor to determine whether the melanocyte (pigment cell) produces phaeomelanin (a red to yellow pigment), or eumelanin (a brown to black pigment). This interaction is responsible for making distinct light and dark bands in the hairs of animals such as the agouti. In other species such as horses, the agouti gene is responsible for determining which parts of the body will be black. Horses can either have black distributed across its body or can have black only in certain locations such as the tail, ears, mane, and the lower legs. In mice, the agouti gene determines whether the animal will be yellow or grey and brown. The agouti-signaling protein (ASIP) is a competitive antagonist with alpha-Melanocyte-stimulating hormone (α-MSH) to bind with melanocortin 1 receptor (MC1R) proteins. Activation by α-MSH causes production of the darker eumelanin, while activation by ASIP causes production of the redder phaeomelanin. This means that if agouti is expressed then the phenotype will be yellow and if it's not expressed then the phenotype would be grey.
  • 2.5K
  • 08 Nov 2022
Topic Review
Kokum Oil
Kokum oil comes from the seeds of the kokum tree (Garcinia indica). This fruit-bearing tree is also known as the wild mangosten tree, and also the red mangosten tree. This tree belongs to the Guttiferae family of the plant kingdom. Its scientific name is Garcinia indica. The oil extracted from the seeds is edible, and it can also be used for things other than cooking.
  • 2.5K
  • 15 Nov 2022
Topic Review
Magnesia as Alternative Binder
Magnesia, or Magnesium oxide (MgO),  is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium. It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions held together by ionic bonding. Magnesia is mainly produced by the calcination of magnesium carbonate. Calcining at different temperatures produces magnesia of different reactivity. The use of reactive MgO as binder in cementitious materials has its advantages and disadvantages.
  • 2.5K
  • 11 Nov 2020
Topic Review
Building Material
In history there are trends in building materials from being natural to becoming more man-made and composite; biodegradable to imperishable; indigenous (local) to being transported globally; repairable to disposable; chosen for increased levels of fire-safety, and improved seismic resistance.. These trends tend to increase the initial and long term economic, ecological, energy, and social costs of building materials.
  • 2.5K
  • 09 Nov 2022
Topic Review
Chemical-based Methodologies for Fresh Fish Shelf-Life Extension
Due to its characteristics, fresh fish is a highly perishable food with a very short shelf-life under refrigeration. Several methods have been introduced to slow down its deterioration, such as by means of oxygen depletion of the food package (vacuum packaging), or by changing the natural atmosphere that is in contact with the fresh fish (modified atmosphere packaging), or by the use of chemicals generally recognized as safe: such compounds can be directly applied (by dipping or spraying) or incorporated into packaging materials and slowly migrate to the product, exerting a hurdle effect against microbial development and lipid oxidation (active packaging).
  • 2.5K
  • 22 Oct 2021
Topic Review
Geopolymer Binders
Based on numerous studies conducted in recent years, geopolymer binders are considered to be sustainable and environmentally friendly cementitious materials and are attractive in terms of their good cost–performance ratio due to low energy consuming production process and use of secondary raw materials instead of virgin ones [1][2].
  • 2.5K
  • 26 Oct 2020
Topic Review
Thermoplastic Pultrusion
Pultrusion is one of the most efficient methods of producing polymer composite structures with a constant cross-section. Pultruded profiles are widely used in bridge construction, transportation industry, energy sector, and civil and architectural engineering. There are two types of pultrusion: thermoplastic and thermosetting. The main features of thermoplastic pultrusion are discussed below.
  • 2.5K
  • 11 Feb 2021
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