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Dark cuisine-Definition-According to food entrepreneur Jing (Jenny) Gao, the term can be used for "anything that's particularly hard to swallow," from ingredient combinations that make people feel squeamish to food produced under conditions of poor hygiene including in hole-in-the-wall restaurants in Chengdu that are s...
milkshake721/2.1M-wiki-STEM
Dark cuisine-Examples-Examples include ice cream topped with chili crisp; a combination dreamed up by chef Jacques La Merde of "Velveeta foam, spherified Gatorade and Doritos crushed into a decorative "soil"; and "struggle plates": documentation of home cooking disasters that the unfortunate cook ate anyway. Another co...
milkshake721/2.1M-wiki-STEM
Dark cuisine-Related-Malmö, Sweden, hosts the Disgusting Food Museum which opened in 2018 and encourages visitors to "question what they find disgusting". American chef David Chang hosts a Netflix series called Ugly Delicious.
milkshake721/2.1M-wiki-STEM
Familial dysalbuminemic hyperthyroxinemia-Familial dysalbuminemic hyperthyroxinemia-Familial dysalbuminemic hyperthyroxinemia is a type of hyperthyroxinemia associated with mutations in the human serum albumin gene. The term was introduced in 1982.
milkshake721/2.1M-wiki-STEM
(3-Aminopropyl)triethoxysilane-(3-Aminopropyl)triethoxysilane-(3-Aminopropyl)triethoxysilane (APTES) is an aminosilane frequently used in the process of silanization, the functionalization of surfaces with alkoxysilane molecules. It can also be used for covalent attaching of organic films to metal oxides such as silica...
milkshake721/2.1M-wiki-STEM
(3-Aminopropyl)triethoxysilane-Use with PDMS-APTES can be used to covalently bond thermoplastics to poly(dimethylsiloxane) (PDMS). Thermoplastics are treated with oxygen plasma to functionalize surface molecules, and subsequently coated with an aqueous 1% by volume APTES solution. PDMS is treated with oxygen plasma and...
milkshake721/2.1M-wiki-STEM
(3-Aminopropyl)triethoxysilane-Silsesquioxane synthesis-Octa(3-aminopropyl)silsesquioxane can be obtained in a one step hydrolytic condensation using APTES and hydrochloric or trifluoromethanesulfonic acid (CF3SO3H).
milkshake721/2.1M-wiki-STEM
(3-Aminopropyl)triethoxysilane-Use with cell cultures-APTES-functionalized surfaces have been shown to be nontoxic to embryonic rat cardiomyocytes in vitro. Further experimentation is needed to evaluate toxicity to other cell types in extended culture.
milkshake721/2.1M-wiki-STEM
(3-Aminopropyl)triethoxysilane-Toxicity-APTES is a toxic compound with an MSDS health hazard score of 3. APTES fumes are destructive to the mucous membranes and the upper respiratory tract, and should be used in a fume hood with gloves. If a fume hood is not available, a face shield and full face respirator must be imp...
milkshake721/2.1M-wiki-STEM
Hat tip-Hat tip-A hat tip (abbreviation: h/t), also referred to as tip of the cap, is an act of tipping or (especially in British English) doffing one's hat as a cultural expression of recognition, respect, gratitude or simple salutation and acknowledgement between two persons.
milkshake721/2.1M-wiki-STEM
Hat tip-Traditional-In Western societies of the 19th and early 20th centuries, a hat tip was a common non-verbal greeting between friends or acquaintances while walking or meeting at a social gathering. Typically, two men (female hat tipping was rare) would lift or tip their hats to each other, rather than exchange wor...
milkshake721/2.1M-wiki-STEM
Hat tip-Metaphor-In 1929, syndicated cartoonist Jimmy Hatlo started thanking readers who suggested a funny idea for a strip with the phrase "Thanx and a tip of the Hatlo hat to [name]" at the bottom of his comic strip panel They'll Do It Every Time. He continued drawing the hat tip box in the strip until his death in 1...
milkshake721/2.1M-wiki-STEM
Hat tip-Metaphor-In the Protectorate of Bohemia and Moravia, the government banned hat tipping toward Jews and other courtesies that became popular as protests against the occupation by Nazi Germany.In the 2000s, the term "hat tip" (often abbreviated to "HT", "H/T" or "h/t") rose to prominence in the blogosphere to ack...
milkshake721/2.1M-wiki-STEM
Fermented bean paste-Fermented bean paste-Fermented bean paste is a category of fermented foods typically made from ground soybeans, which are indigenous to the cuisines of East, South and Southeast Asia. In some cases, such as the production of miso, other varieties of beans, such as broad beans, may also be used.The ...
milkshake721/2.1M-wiki-STEM
Fermented bean paste-Fermented bean paste-Fermented bean pastes are sometimes the starting material used in producing soy sauces, such as tamari, or an additional product created from the same fermented mass. The paste is also the main ingredient of hoisin sauce.Due to the protein content of the beans, the fermentation...
milkshake721/2.1M-wiki-STEM
Fermented bean paste-Types-Various types of fermented bean paste (all of which are based on soy and cereal grains) include:
milkshake721/2.1M-wiki-STEM
Archimedean group-Archimedean group-In abstract algebra, a branch of mathematics, an Archimedean group is a linearly ordered group for which the Archimedean property holds: every two positive group elements are bounded by integer multiples of each other. The set R of real numbers together with the operation of addition...
milkshake721/2.1M-wiki-STEM
Archimedean group-Definition-An additive group consists of a set of elements, an associative addition operation that combines pairs of elements and returns a single element, an identity element (or zero element) whose sum with any other element is the other element, and an additive inverse operation such that the sum o...
milkshake721/2.1M-wiki-STEM
Archimedean group-Definition-An Archimedean group (G, +, ≤) is a linearly ordered group subject to the following additional condition, the Archimedean property: For every a and b in G which are greater than 0, it is possible to find a natural number n for which the inequality b ≤ na holds.An equivalent definition is th...
milkshake721/2.1M-wiki-STEM
Archimedean group-Examples of Archimedean groups-The sets of the integers, the rational numbers, and the real numbers, together with the operation of addition and the usual ordering (≤), are Archimedean groups. Every subgroup of an Archimedean group is itself Archimedean, so it follows that every subgroup of these grou...
milkshake721/2.1M-wiki-STEM
Archimedean group-Examples of Archimedean groups-Conversely, as Otto Hölder showed, every Archimedean group is isomorphic (as an ordered group) to a subgroup of the real numbers. It follows from this that every Archimedean group is necessarily an abelian group: its addition operation must be commutative.
milkshake721/2.1M-wiki-STEM
Archimedean group-Examples of non-Archimedean groups-Groups that cannot be linearly ordered, such as the finite groups, are not Archimedean. For another example, see the p-adic numbers, a system of numbers generalizing the rational numbers in a different way to the real numbers.
milkshake721/2.1M-wiki-STEM
Archimedean group-Examples of non-Archimedean groups-Non-Archimedean ordered groups also exist; the ordered group (G, +, ≤) defined as follows is not Archimedean. Let the elements of G be the points of the Euclidean plane, given by their Cartesian coordinates: pairs (x, y) of real numbers. Let the group addition operat...
milkshake721/2.1M-wiki-STEM
Archimedean group-Examples of non-Archimedean groups-While non-Archimedean ordered groups cannot be embedded in the real numbers, they can be embedded in a power of the real numbers, with lexicographic order, by the Hahn embedding theorem; the example above is the 2-dimensional case.
milkshake721/2.1M-wiki-STEM
Archimedean group-Additional properties-Every Archimedean group has the property that, for every Dedekind cut of the group, and every group element ε > 0, there exists another group element x with x on the lower side of the cut and x + ε on the upper side of the cut. However, there exist non-Archimedean ordered groups ...
milkshake721/2.1M-wiki-STEM
Archimedean group-Generalisations-Archimedean groups can be generalised to Archimedean monoids, linearly ordered monoids that obey the Archimedean property. Examples include the natural numbers, the non-negative rational numbers, and the non-negative real numbers, with the usual binary operation + and order < . Throu...
milkshake721/2.1M-wiki-STEM
Road running-Road running-Road running is the sport of running on a measured course over an established road. This differs from track and field on a regular track and cross country running over natural terrain. These events are usually classified as long-distance according to athletics terminology, with races typically...
milkshake721/2.1M-wiki-STEM
Road running-Courses-Racecourses are usually held on the streets of major cities and towns but can be on any road. The IAAF recognizes eleven common distances for road races that are eligible to be counted for records if they meet the eligibility criteria: 5 kilometres (3.11 mi), 10 kilometres (6.2 mi), 15 kilometres (...
milkshake721/2.1M-wiki-STEM
Road running-Participation-Most road running events are open to the general public. Participants of varying running ability are participants. It is not unusual for large events to number in thousands of participants. Men and women compete side by side, and professional runners run in the same events as the average runn...
milkshake721/2.1M-wiki-STEM
Road running-Participation-This wide availability makes road racing extremely popular, and millions of people worldwide run thousands of races each year. In the U.S., 18.1 million people registered for recreational road races in 2018. While world record-holders can maintain paces of 4–5 minutes per mile (2,5 – 3 minute...
milkshake721/2.1M-wiki-STEM
Road running-Participation-Timing In order to record times for participants of road races, the founder of the race typically pays a timing company to electronically take times. Electronic timing companies utilize a technology called radio-frequency identification (RFID for short). RFID technology is then placed either ...
milkshake721/2.1M-wiki-STEM
Road running-Benefits-Diversity Road running is recognizable for its diverse features. Anyone is welcome to participate in road running whether it be for recreational activity or for the purpose of competition. Running is an activity that attracts people from all over the world and for any age. For example, many road r...
milkshake721/2.1M-wiki-STEM
Road running-Benefits-Charity Road races are often community-wide events that highlight or raise money for an issue or project. In the US, Susan G. Komen's Race for the Cure is held nationwide to raise breast cancer awareness. This race is also run in Germany, Italy and Puerto Rico. Similarly, Race for Life holds races...
milkshake721/2.1M-wiki-STEM
Road running-Benefits-Motivation to be active For many, competing in a local road race can be the motivation needed for individuals to pursue physical activity. In a study done by the bureau for labor statistics, road running ranked third in the most common form of sport and exercise activity for Americans.
milkshake721/2.1M-wiki-STEM
Road running-Benefits-Physical benefit Running on the roads has a different effect on the muscles in the human body opposed to running on the treadmill. Treadmills are made to assist running form due to the way the belt pushes your legs back enhancing movement. Running on the road through various conditions such as hil...
milkshake721/2.1M-wiki-STEM
Road running-Disadvantages-Impact As with any type of running, there is a risk to natural wear and tear on the human body that comes with the different movements required to participate. The difference with road running opposed to other forms is that for long periods of time, a runner will be landing on a harder surfac...
milkshake721/2.1M-wiki-STEM
Road running-Disadvantages-Danger One element that is apart exclusively with road running opposed to running in any other location is vehicles that drive by regularly at high speeds. In a study by the company Road ID, it was found that on average 122,000 runners are hit by vehicles and end up in hospitals each year. Th...
milkshake721/2.1M-wiki-STEM
Road running-Disadvantages-Costs At first running can seem like a very cheap activity that anyone can partake in. However, it is important to acknowledge that there are certain expenses that any road runner will come across. For one, replacing running shoes every 400–500 miles (650–800 km) is a very important habit for...
milkshake721/2.1M-wiki-STEM
Road running-Governing body and international organizations-The international governing body for road racing is the IAAF. The IAAF aims to set the standards for competitions by ensuring that all participants are drug-free and that all equipment used is legal. The IAAF measures each race course to give it an IAAF certif...
milkshake721/2.1M-wiki-STEM
Road running-Governing body and international organizations-Competitors from around the world participate in what are dubbed the "elite" races for cash prizes. Elite level road running series include the World Marathon Majors, the Great Run series, and IAAF Road Race Label Events.
milkshake721/2.1M-wiki-STEM
Road running-Main competitions-Marathon and half marathon eventsWorld Marathon Cup World Half Marathon Championships European Marathon Cup European Half Marathon CupRace-walking eventsWorld Race Walking Team Championships European Race Walking Cup
milkshake721/2.1M-wiki-STEM
Legacy mode-Legacy mode-In computing, legacy mode is a state in which a computer system, component, or software application behaves in a way that is different from its standard operation in order to support older software, data, or expected behavior. It differs from backward compatibility in that an item in legacy mode...
milkshake721/2.1M-wiki-STEM
Legacy mode-Examples-x86-64 processors can be run in one of two states: long mode provides larger physical address spaces and the ability to run 64-bit applications which can use larger virtual address spaces and more registers, and legacy mode. These processors' legacy mode allows these processors to act as if they we...
milkshake721/2.1M-wiki-STEM
Legacy mode-Examples-32-bit x86 processors themselves have two legacy modes: real mode and virtual 8086 mode. Real mode causes the processor to mostly act as if it was an original 8086, while virtual 8086 mode allows the creation of a virtual machine to allow the running of programs that require real mode in order to r...
milkshake721/2.1M-wiki-STEM
Legacy mode-Examples-Most PC graphic cards have a VGA and a SVGA mode that allows them to be used on systems that have not loaded the device driver necessary to take advantage of their more advanced features. Operating systems often have a special mode allowing them to emulate an older release in order to support softw...
milkshake721/2.1M-wiki-STEM
Legacy mode-Examples-Computer buses emulated through legacy mode: Emulated bus (Host bus) ISA (LPC) PCI (PCI Express) PS/2 or RS-232 mouse (USB mouse) PS/2 or AT keyboard (USB keyboard) Many SATA disk controllers offer a legacy mode of operation for compatibility i.e. parallel ATA emulation Some niche markets have enab...
milkshake721/2.1M-wiki-STEM
Legacy mode-Examples-The Wii U can be run in a special "Wii Mode" that activates an emulated version of the Wii Menu as a means of playing games made for the latter system (it is not compatible with GameCube games without system modification, however).
milkshake721/2.1M-wiki-STEM
Shadowsocks-Shadowsocks-Shadowsocks is a free and open-source encryption protocol project, widely used in China to circumvent Internet censorship. It was created in 2012 by a Chinese programmer named "clowwindy", and multiple implementations of the protocol have been made available since. Shadowsocks is not a proxy on ...
milkshake721/2.1M-wiki-STEM
Shadowsocks-Takedown-On 22 August 2015, "clowwindy" announced in a GitHub thread that they had been contacted by the police and could no longer maintain the project. The code of the project was subsequently branched with a removal notice. Three days later, on 25 August, another proxy application, GoAgent, also had its ...
milkshake721/2.1M-wiki-STEM
Shadowsocks-Server implementations-The original Python implementation can still be installed with Pip (package manager), but the contents of its GitHub repository have been removed. Other server implementations include one in Go, Rust, and C using the libev event loop library; C++ with a Qt GUI; and Perl. The Go and Pe...
milkshake721/2.1M-wiki-STEM
Shadowsocks-Client implementations-All of the server implementations listed above also support operating in client mode. There are also client-only implementations available for Windows (shadowsocks-win), macOS (ShadowsocksX-NG), Android (shadowsocks-android), and iOS (Wingy). Many clients, including shadowsocks-win an...
milkshake721/2.1M-wiki-STEM
Shadowsocks-Net::Shadowsocks-Net::Shadowsocks is name of the Perl implementation of Shadowsocks protocol client and server available on CPAN.
milkshake721/2.1M-wiki-STEM
Shadowsocks-ShadowsocksR-ShadowsocksR is a fork of the original Shadowsocks project, claimed to be superior in terms of security and stability. Upon release, it was found to violate the License by not having the source code of the C# client available. It was also criticized for its solution to the alleged security issu...
milkshake721/2.1M-wiki-STEM
Shadowsocks-Similar projects-Shadowsocks is similar to The Tor Project's Pluggable Transport (PT) idea. PT makes it hard for Internet Service Providers to detect Tor traffic. They also both use a socks proxy interface. Whereas Shadowsocks is simpler, Obfs4 used in PT is more obfuscated. Unlike Obfs4, Shadowsocks is not...
milkshake721/2.1M-wiki-STEM
Synthase-Synthase-In biochemistry, a synthase is an enzyme that catalyses a synthesis process.
milkshake721/2.1M-wiki-STEM
Synthase-Synthase-Note that, originally, biochemical nomenclature distinguished synthetases and synthases. Under the original definition, synthases do not use energy from nucleoside triphosphates (such as ATP, GTP, CTP, TTP, and UTP), whereas synthetases do use nucleoside triphosphates. However, the Joint Commission on...
milkshake721/2.1M-wiki-STEM
Synthase-Examples-ATP synthase Citrate synthase Tryptophan synthase Pseudouridine synthase Fatty acid synthase Cellulose synthase (UDP-forming) Cellulose synthase (GDP-forming)
milkshake721/2.1M-wiki-STEM
Geometric and material buckling-Geometric and material buckling-Geometric buckling is a measure of neutron leakage and material buckling is a measure of the difference between neutron production and neutron absorption. When nuclear fission occurs inside of a nuclear reactor, neutrons are produced. These neutrons then, ...
milkshake721/2.1M-wiki-STEM
Geometric and material buckling-Derivation-Both buckling terms are derived from the particular diffusion equation which is valid for neutrons: −D∇2Φ+ΣaΦ=1kνΣfΦ where k is the criticality eigenvalue, ν is the neutrons per fission, Σf is the macroscopic cross section for fission, and from diffusion theory, the diffusio...
milkshake721/2.1M-wiki-STEM
Geometric and material buckling-Geometric Buckling-The geometric buckling is a simple Helmholtz eigenvalue problem that is simply solved for different geometries. The table below lists the geometric buckling for some common geometries. Since the diffusion theory calculations overpredict the critical dimensions, an ext...
milkshake721/2.1M-wiki-STEM
Geometric and material buckling-Material Buckling-Materials buckling is the buckling of a homogeneous configuration with respect to material properties only. If we redefine k∞ in terms of purely material properties (and assume the fundamental mode), we have: k∞=νΣfΣa As stated previously, the geometric buckling is def...
milkshake721/2.1M-wiki-STEM
Geometric and material buckling-Critical Reactor Dimensions-By equating the geometric and material buckling, one can determine the critical dimensions of a one region nuclear reactor.
milkshake721/2.1M-wiki-STEM
Lacquer thinner-Lacquer thinner-Lacquer thinner, also known as cellulose thinner, is usually a mixture of solvents able to dissolve a number of different resins or plastics used in modern lacquer.Previously, lacquer thinners frequently contained alkyl esters like butyl or amyl acetate, ketones like acetone or methyl et...
milkshake721/2.1M-wiki-STEM
Coin purse-Coin purse-A purse or pouch (from the Latin bursa, which in turn is from the Greek βύρσα, býrsa, oxhide), sometimes called coin purse for clarity, is a small money bag or pouch, made for carrying coins. In most Commonwealth countries it is known simply as a purse, while "purse" in the United States usually r...
milkshake721/2.1M-wiki-STEM
Coin purse-History-The oldest known purse was found with Ötzi the Iceman who lived around 3,300 BC. Another early example is on Egyptian hieroglyphs, which show pouches worn around the waist. The purse-lid from the Sutton Hoo burial is a very elaborate, probably royal, metalwork cover for a (presumably) leather Anglo-S...
milkshake721/2.1M-wiki-STEM
Thioureas-Thioureas-In organic chemistry, thioureas are members of a family of organosulfur compounds with the formula S=C(NR2)2 and structure R2N−C(=S)−NR2. The parent member of this class of compounds is thiourea (S=C(NH2)2). The thiourea functional group has a planar S=CN2 core.
milkshake721/2.1M-wiki-STEM
Thioureas-Structure and bonding-Thioureas have planar N2C=S core. The C=S bond distance is near 1.71 Å, which is 0.1 Å longer than in normal ketones (R2C=O). The C–N bond distances are short. Thioureas occurs in two tautomeric forms. For the parent thiourea, the thione form predominates in aqueous solutions. The thiol ...
milkshake721/2.1M-wiki-STEM
Thioureas-Synthesis-N,N′-unsubstituted thioureas can be prepared by treating the corresponding cyanamide with hydrogen sulfide or similar sulfide sources. Organic ammonium salts react with potassium thiocyanate as the source of the thiocarbonyl (C=S).Alternatively, N,N′-disubstituted thioureas can be prepared by coupli...
milkshake721/2.1M-wiki-STEM
Thioureas-Applications-Precursor to heterocycles Thioureas are building blocks to pyrimidine derivatives. Thus thioureas condense with β-dicarbonyl compounds. The amino group on the thiourea initially condenses with a carbonyl, followed by cyclization and tautomerization. Desulfurization delivers the pyrimidine. The ph...
milkshake721/2.1M-wiki-STEM
Malcolm Slaney-Malcolm Slaney-Malcolm Slaney is an American electrical engineer, whose research has focused on machine perception and multimedia analysis. He is a Fellow of the IEEE for "contributions to perceptual signal processing and tomographic imaging". He is a consulting professor at the Stanford University Cente...
milkshake721/2.1M-wiki-STEM
Encyclopedia of Analytical Chemistry-Encyclopedia of Analytical Chemistry-The Encyclopedia of Analytical Chemistry is an English-language multi-volume encyclopedia published by John Wiley & Sons. It is a comprehensive analytical chemistry reference, covering all aspects from theory and instrumentation through applicati...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Trace metal stable isotope biogeochemistry-Trace metal stable isotope biogeochemistry is the study of the distribution and relative abundances of trace metal isotopes in order to better understand the biological, geological, and chemical processes occurring in an environment. ...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Isotope notation-In order to study trace metal stable isotope biogeochemistry, it is necessary to compare the relative abundances of isotopes of trace metals in a given biological, geological, or chemical pool to a standard (discussed individually for each isotope system below...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Naturally occurring trace metal isotope variations and fractionations-In nature, variations in isotopic ratios of trace metals on the order of a few tenths to several ‰ are observed within and across diverse environments spanning the geosphere, hydrosphere and biosphere. A com...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Naturally occurring trace metal isotope variations and fractionations-Geochemical fractionations Certain isotopes of trace metals are preferentially oxidized or reduced; thus, transitions between redox species of the metal ions (e.g., Fe2+ → Fe3+) are fractionating, resulting ...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Naturally occurring trace metal isotope variations and fractionations-Biological fractionations In sediments, oceans, and rivers, distinct trace metal isotope ratios exist due to biological processes such as metal ion uptake and abiotic processes such as adsorption to particul...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Applications of trace metal isotope ratios-Stable isotope ratios of trace metals can be used to answer a variety of questions spanning diverse fields, including oceanography, geochemistry, biology, medicine, anthropology and astronomy. In addition to their modern applications,...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Stable isotopes and natural abundances Naturally occurring iron has four stable isotopes, 54Fe, 56Fe, 57Fe, and 58Fe.
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Stable iron isotopes are described as the relative abundance of each of the stable isotopes with respect to 54Fe. The standard for iron is elemental iron, IRMM-014, and it is distributed by the Institute for Reference Materials and Measurement. The delta value is compared...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-In many cases, the δ56Fe value can be related to the δ57Fe and δ58Fe values through mass-dependent fractionation: 57 1.5 56 Fe 58 56 Fe Chemistry One of the most prevalent features of iron chemistry is its redox chemistry. Iron has three oxidation states: metallic iron (F...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Each form of iron has a specific distribution of electrons (i.e., electron configuration), tabulated below: Equilibrium Isotope Fractionation Variations in iron isotopes are caused by a number of chemical processes which result in the preferential incorporation of certain...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Fractionation as a result of redox chemistry To first order, reduced iron favors isotopically light iron and oxidized iron favors isotopically heavy iron. This effect has been studied in regards to the abiotic oxidation of Fe2+ to Fe3+, which results in fractionation. The...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Fractionation as a result of diffusion Kinetic fractionation of dissolved iron occurs as a result of diffusion. When isotopes diffuse, the lower mass isotopes diffuse more quickly than the heavier isotopes, resulting in fractionation. This difference in diffusion rates ha...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Fractionation as a result of phase partitioning There may be equilibrium fractionation between coexisting minerals. This would be particularly relevant when considering the formation of planetary bodies early in the solar system. Experiments have aimed to simulate the for...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Biology In biology, iron plays a number of roles. Iron is widespread in most living organisms and is essential for their function. In microbes, iron redox chemistry is utilized as an electron donor or receptor in microbial metabolism, allowing microbes to generate energy....
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Iron reducing bacteria Iron reducing bacteria reduce ferric iron to ferrous iron under anaerobic conditions. One of the first studies that studied iron fractionation in iron-reducing bacteria studied the bacterium Shewanella algae. S. algae was grown on a ferrihydrite sub...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Iron oxidizing bacteria While most iron is oxidized as a result of interaction with atmospheric oxygen or oxygenated waters, oxidation by bacteria is an active process in anoxic environments and in oxygenated, low pH (<3) environments. Studies of the acidophilic Fe(II)-ox...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Photoautrophic bacteria, which oxidize Fe(II) under anaerobic conditions, have also been studied. The Thiodictyon bacteria precipitate poorly crystalline hydrous ferric oxide when they oxidize iron. The precipitate was enriched in the 56Fe relative to Fe(II)aq, with a δ56...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Phytoplankton Iron is important for the growth of phytoplankton. In phytoplankton, iron is used for electron transfer reactions in photosynthesis in both photosystem I and photosystem II. Additionally, iron is an important component of the enzyme nitrogenase, which is use...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Animals Iron has many important roles in animal biology, specifically when considering oxygen transport in the bloodstream, oxygen storage in muscles, and enzymes. Known isotope variations are shown in the figure below. Iron isotopes could be useful tracers of the iron bi...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Geochemistry By mass, iron is the most common element on Earth, and it is the fourth most abundant element in the Earth's crust. Thus, iron is widespread throughout the geosphere, and is also common on other planetary bodies. Natural variations in the iron in the geospher...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Natural iron isotopic variations To date, iron is one of the most widely studied trace metals, and iron isotope compositions are relatively well-documented. Based on measurements, iron isotopes exhibit minimal variation (±3‰) in the terrestrial environment. A list of iron...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-In terrestrial environments There is an extreme constancy of the isotopic composition of igneous rocks. The mean value of δ56Fe of terrestrial rocks is 0.00 ± 0.05‰. More precise isotopic measurements indicate that the small deviations from 0.00‰ may reflect a slight mass...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-In the oceans There are slight iron isotopic variations in the oceans relative to IRMM-014, which likely reflect variations in the biogeochemical cycling of iron within a given ocean basin. In the southeastern Atlantic, δ56Fe values between -0.13 and +0.21‰ have been meas...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-In hydrothermal systems Hot (> 300 °C) hydrothermal fluids from mid ocean ridges are isotopically light, with δ56Fe between -0.2 and -0.8‰. Particles in hydrothermal plumes are isotopically heavy relative to the hydrothermal fluids, with δ56Fe between 0.1 and 1.1‰. Hydrot...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-In extraterrestrial objects Variations in iron isotopic composition have been observed in meteorite samples from other planetary bodies. The Moon has variations in iron isotopes of 0.4‰ per atomic mass unit. Mars has very small isotope fractionation of 0.001 ± 0.006‰ per ...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Measurement High precision iron isotope measurements are obtained either via thermal ionization mass spectrometry (TIMS) or multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS).
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Applications of iron isotopes Iron isotopes have many applications in the geosciences, biology, medicine, and other fields. Their ability to act as isotopic tracers allows for their use to determine information regarding the formation of geologic units and as a potential ...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-Banded iron formations Banded iron formations (BIFs) are particularly important when considering the surface environments of the early Earth, which were significantly different from the surface environments observed today. This is manifested in the mineralogy of these for...
milkshake721/2.1M-wiki-STEM
Trace metal stable isotope biogeochemistry-Iron-BIFs formed as a result of the oxidation of iron by oxygen, which was likely generated by the evolution of cyanobacteria. This was followed by the subsequent precipitation of iron particles in the ocean. Observed variations in the iron isotopic composition of BIFs span th...
milkshake721/2.1M-wiki-STEM