Topic: Chemistry

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πŸ”— Dry Water

πŸ”— Chemistry

Dry water , an unusual form of "powdered liquid", is a water–air emulsion in which tiny water droplets, each the size of a grain of sand, are surrounded by a sandy silica coating. Dry water actually consists of 95% liquid water, but the silica coating prevents the water droplets from combining and turning back into a bulk liquid. The result is a white powder that looks very similar to table salt. It is also more commonly known among researchers as empty water.

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πŸ”— Starlite

πŸ”— Brands πŸ”— Chemistry πŸ”— Invention πŸ”— Polymers

Starlite is an intumescent material claimed to be able to withstand and insulate from extreme heat. It was invented by British amateur chemist and hairdresser Maurice Ward (1933-2011) during the 1970s and 1980s, and received significant publicity after coverage of the material aired in 1990 on the BBC science and technology show Tomorrow's World. The name Starlite was coined by Ward's granddaughter Kimberly.

The American company Thermashield, LLC claims to have acquired the rights to Starlite in 2013 and replicated it. It is the only company to have itself publicly demonstrated the technology and have samples tested by third parties.

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πŸ”— Hiding Nobel prizes in plain sight

πŸ”— Chemistry

Aqua regia (; from Latin, lit. "regal water" or "king's water") is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. Aqua regia is a yellow-orange (sometimes red) fuming liquid, so named by alchemists because it can dissolve the noble metals, gold and platinum, though not all metals.

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πŸ”— Mirror life

πŸ”— Biology πŸ”— Molecular and Cell Biology πŸ”— Chemistry πŸ”— Genetics

Mirror life (also called mirror-image life, chiral life, or enantiomeric life) is a hypothetical form of life with mirror-reflected molecular building blocks. The possibility of mirror life was first discussed by Louis Pasteur. Although this alternative life form has not been discovered in nature, efforts to build a mirror-image version of biology's molecular machinery are already underway.

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πŸ”— Marvin Pipkin, inventor of the frosted light bulb

πŸ”— Biography πŸ”— Chemistry πŸ”— Florida

Marvin Pipkin (November 18, 1889 – January 7, 1977) was an American chemist. During his time in the United States Army he worked on gas masks. In his civilian life he invented a process for frosting the inside of incandescent light bulbs to cut down on the sharp glare and diffuse the light. He went on to make many other inventions and innovative improvements to the light bulb.

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πŸ”— Terfenol-D

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Chemistry

Terfenol-D, an alloy of the formula TbxDy1βˆ’xFe2 (xΒ β‰ˆΒ 0.3), is a magnetostrictive material. It was initially developed in the 1970s by the Naval Ordnance Laboratory in United States. The technology for manufacturing the material efficiently was developed in the 1980s at Ames Laboratory under a U.S. Navy-funded program. It is named after terbium, iron (Fe), Naval Ordnance Laboratory (NOL), and the D comes from dysprosium.

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πŸ”— Hypothetical types of biochemistry

πŸ”— Biology πŸ”— Science Fiction πŸ”— Chemistry

Hypothetical types of biochemistry are forms of biochemistry speculated to be scientifically viable but not proven to exist at this time. The kinds of living organisms currently known on Earth all use carbon compounds for basic structural and metabolic functions, water as a solvent, and DNA or RNA to define and control their form. If life exists on other planets or moons, it may be chemically similar; it is also possible that there are organisms with quite different chemistriesβ€”for instance, involving other classes of carbon compounds, compounds of another element, or another solvent in place of water.

The possibility of life-forms being based on "alternative" biochemistries is the topic of an ongoing scientific discussion, informed by what is known about extraterrestrial environments and about the chemical behaviour of various elements and compounds. It is of interest in synthetic biology and is also a common subject in science fiction.

The element silicon has been much discussed as a hypothetical alternative to carbon. Silicon is in the same group as carbon on the periodic table and, like carbon, it is tetravalent. Hypothetical alternatives to water include ammonia, which, like water, is a polar molecule, and cosmically abundant; and non-polar hydrocarbon solvents such as methane and ethane, which are known to exist in liquid form on the surface of Titan.

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πŸ”— β€œJack” Parsons was an American rocket engineer, chemist, & Thelemite occultist

πŸ”— United States πŸ”— Biography πŸ”— California πŸ”— Aviation πŸ”— Spaceflight πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Biography/science and academia πŸ”— Military history/Military biography πŸ”— Biography/military biography πŸ”— LGBT studies πŸ”— Aviation/aerospace biography project πŸ”— Chemistry πŸ”— Military history/World War II πŸ”— Military history/Cold War πŸ”— Libertarianism πŸ”— California/Southern California πŸ”— California/Los Angeles area πŸ”— Thelema πŸ”— Occult

John Whiteside Parsons (born Marvel Whiteside Parsons; October 2, 1914 – June 17, 1952) was an American rocket engineer, chemist, and Thelemite occultist. Associated with the California Institute of Technology (Caltech), Parsons was one of the principal founders of both the Jet Propulsion Laboratory (JPL) and the Aerojet Engineering Corporation. He invented the first rocket engine to use a castable, composite rocket propellant, and pioneered the advancement of both liquid-fuel and solid-fuel rockets.

Born in Los Angeles, Parsons was raised by a wealthy family on Orange Grove Boulevard in Pasadena. Inspired by science fiction literature, he developed an interest in rocketry in his childhood and in 1928 began amateur rocket experiments with school friend Edward S. Forman. He dropped out of Pasadena Junior College and Stanford University due to financial difficulties during the Great Depression, and in 1934 he united with Forman and graduate Frank Malina to form the Caltech-affiliated Guggenheim Aeronautical Laboratory (GALCIT) Rocket Research Group, supported by GALCIT chairman Theodore von KΓ‘rmΓ‘n. In 1939 the GALCIT Group gained funding from the National Academy of Sciences (NAS) to work on Jet-Assisted Take Off (JATO) for the U.S. military. After the U.S. entered World War II, they founded Aerojet in 1942 to develop and sell JATO technology; the GALCIT Group became JPL in 1943.

Following some brief involvement with Marxism in 1939, Parsons converted to Thelema, the new religious movement founded by the English occultist Aleister Crowley. Together with his first wife, Helen Northrup, Parsons joined the Agape Lodge, the Californian branch of the Thelemite Ordo Templi Orientis (O.T.O.) in 1941. At Crowley's bidding, Parsons replaced Wilfred Talbot Smith as its leader in 1942 and ran the Lodge from his mansion on Orange Grove Boulevard. Parsons was expelled from JPL and Aerojet in 1944 owing to the Lodge's infamous reputation and to his hazardous workplace conduct.

In 1945, Parsons separated from Helen, after having an affair with her sister Sara; when Sara left him for L. Ron Hubbard, Parsons conducted the Babalon Working, a series of rituals intended to invoke the Thelemic goddess Babalon on Earth. He and Hubbard continued the working with Marjorie Cameron, whom Parsons married in 1946. After Hubbard and Sara defrauded him of his life savings, Parsons resigned from the O.T.O., then held various jobs while acting as a consultant for Israel's rocket program. Amid McCarthyism, Parsons was accused of espionage and left unable to work in rocketry. In 1952 Parsons died at the age of 37 in a home laboratory explosion that attracted national media attention; the police ruled it an accident, but many associates suspected suicide or murder.

Parsons's libertarian and occult writings were published posthumously. Historians of Western esoteric tradition cite him as one of the more prominent figures in propagating Thelema across North America. Although academic interest in his scientific career was negligible, historians have come to recognize Parsons's contributions to rocket engineering. For these innovations, his advocacy of space exploration and human spaceflight, and his role in founding JPL and Aerojet, Parsons is regarded as among the most important figures in the history of the U.S. space program. He has been the subject of several biographies and fictionalized portrayals.

πŸ”— Relativistic Quantum Chemistry

πŸ”— Physics πŸ”— Physics/relativity πŸ”— Chemistry

Relativistic quantum chemistry combines relativistic mechanics with quantum chemistry to explain elemental properties and structure, especially for the heavier elements of the periodic table. A prominent example of such an explanation is the color of gold: due to relativistic effects, it is not silvery like most other metals.

The term relativistic effects was developed in light of the history of quantum mechanics. Initially quantum mechanics was developed without considering the theory of relativity. Relativistic effects are those discrepancies between values calculated by models that consider and that do not consider relativity. Relativistic effects are important for the heavier elements with high atomic numbers. In the most common layout of the periodic table, these elements are shown in the lower area. Examples are the lanthanides and actinides.

Relativistic effects in chemistry can be considered to be perturbations, or small corrections, to the non-relativistic theory of chemistry, which is developed from the solutions of the SchrΓΆdinger equation. These corrections affect the electrons differently depending on the electron speed relative to the speed of light. Relativistic effects are more prominent in heavy elements because only in these elements do electrons attain sufficient speeds for the elements to have properties that differ from what non-relativistic chemistry predicts.

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πŸ”— Vanadium redox battery

πŸ”— Chemistry

The vanadium redox battery (VRB), also known as the vanadium flow battery (VFB) or vanadium redox flow battery (VRFB), is a type of rechargeable flow battery that employs vanadium ions in different oxidation states to store chemical potential energy. The vanadium redox battery exploits the ability of vanadium to exist in solution in four different oxidation states, and uses this property to make a battery that has just one electroactive element instead of two. For several reasons, including their relative bulkiness, most vanadium batteries are currently used for grid energy storage, i.e., attached to power plants or electrical grids.

The possibility of creating a vanadium flow battery was explored by Pissoort in the 1930s, NASA researchers in the 1970s, and Pellegri and Spaziante in the 1970s, but none of them were successful in demonstrating the technology. The first successful demonstration of the all-vanadium redox flow battery which employed vanadium in a solution of sulfuric acid in each half was by Maria Skyllas-Kazacos at the University of New South Wales in the 1980s. Her design used sulfuric acid electrolytes, and was patented by the University of New South Wales in Australia in 1986.

The main advantages of the vanadium redox battery are that it can offer almost unlimited energy capacity simply by using larger electrolyte storage tanks; it can be left completely discharged for long periods with no ill effects; if the electrolytes are accidentally mixed, the battery suffers no permanent damage; a single state of charge between the two electrolytes avoids the capacity degradation due to a single cell in non-flow batteries; the electrolyte is aqueous and inherently safe and non-flammable; and the generation 3 formulation using a mixed acid solution developed by the Pacific Northwest National Laboratory operates over a wider temperature range allowing for passive cooling. VRFBs can be used at depth of discharge (DOD) around 90% and more, i.e. deeper DODs than solid-state batteries (e.g. lithium-based and sodium-based batteries, which are usually specified with DOD=80%). In addition, VRFBs exhibit very long cycle lives: most producers specify cycle durability in excess of 15,000-20,000 charge/discharge cycles. These values are far beyond the cycle lives of solid-state batteries, which is usually in the order of 4,000-5,000 charge/discharge cycles. Consequently, the levelized cost of energy (LCOE, i.e. the system cost divided by the usable energy, the cycle life, and round-trip efficiency) of present VRFB systems is typically in the order of a few tens of $ cents or € cents, namely much lower than the LCOEs of equivalent solid-state batteries and close to the targets of $0.05 and €0.05, stated by the US Department of Energy and the European Commission Strategic Energy Technology (SET) Plan, respectively.

The main disadvantages with vanadium redox technology are a relatively poor energy-to-volume ratio in comparison with standard storage batteries, and the relatively poor round trip efficiency. Furthermore, the aqueous electrolyte makes the battery heavy and therefore only useful for stationary applications. Another disadvantage is the relatively high toxicity of oxides of vanadium (see vanadium § Safety).

Numerous companies and organizations involved in funding and developing vanadium redox batteries include Avalon Battery, Vionx (formerly Premium Power), UniEnergy Technologies and Ashlawn Energy in the United States; Renewable Energy Dynamics Technology in Ireland; Enerox GmbH (formerly Gildemeister energy storage) in Austria; Cellennium in Thailand; Rongke Power in China; Prudent Energy in China; Sumitomo in Japan; H2, Inc. in South Korea; redT in Britain., Australian Vanadium in Australia, and the now defunct Imergy (formerly Deeya). Lately, also several smaller size vanadium redox flow batteries were brought to market (for residential applications) mainly from StorEn Technologies (USA), Schmid Group, VoltStorage and Volterion (all three from Germany), VisBlue (Denmark) or Pinflow energy storage (Czechia).

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