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Perfluorotributylamine
Perfluorotributylamine (PFTBA), also referred to as FC43, is a colorless liquid with the formula N(C4F9)3. The compound consists of three butyl groups connected to an amine center, in which all of the hydrogen atoms have been replaced with fluorine. The compound is produced for the electronics industry, along with other perfluoroalkylamines. The high degree of fluorination significantly reduces the basicity of the central amine due to electron-withdrawing effects. Preparation It is prepared by electrofluorination of tributylamine using hydrogen fluoride as solvent and source of fluorine: :N(C4H9)3 + 27 HF → N(C4F9)3 + 27 H2 Uses The compound has two commercial uses. It is used as an ingredient in Fluosol, artificial blood. This application exploits the high solubility of oxygen and carbon dioxide in the solvent, as well as the low viscosity and toxicity. It is also a component of Fluorinert coolant liquids. CPUs of some computers are immersed in this liquid to facil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhouse Gases
A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), methane (), nitrous oxide (), and ozone (). Without greenhouse gases, the average temperature of Earth's surface would be about , rather than the present average of . The atmospheres of Venus, Mars and Titan also contain greenhouse gases. Human activities since the beginning of the Industrial Revolution (around 1750) have increased the atmospheric concentration of carbon dioxide by over 50%, from 280 ppm in 1750 to 421 ppm in 2022. The last time the atmospheric concentration of carbon dioxide was this high was over 3 million years ago. This increase has occurred despite the absorption of more than half of the emissions by various natural carbon sinks in the carbon cycle. At current greenhouse gas emission rates, temperatures could increas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluorotripentylamine
Perfluorotripentylamine is a perfluorocarbon. It is used as an electronics coolant, and has a high boiling point. It is colorless, odorless, and insoluble in water. Unlike ordinary amines, perfluoroamines are of low basicity. Perfluorinated amines are components of fluorofluids, used as immersive coolants for supercomputers. It is prepared by electrofluorination of the amine using hydrogen fluoride as solvent and source of fluorine: :N(C5H11)3 + 33 HF → N(C5F11)3 + 33 H2 Safety Fluoroamines are generally of very low toxicity, so much that they have been evaluated as synthetic blood. See also * Perfluorotributylamine Perfluorotributylamine (PFTBA), also referred to as FC43, is a colorless liquid with the formula N(C4F9)3. The compound consists of three butyl groups connected to an amine center, in which all of the hydrogen atoms have been replaced with fluori ... References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhouse Gas
A greenhouse gas (GHG or GhG) is a gas that Absorption (electromagnetic radiation), absorbs and Emission (electromagnetic radiation), emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Atmosphere of Earth, Earth's atmosphere are water vapor (), carbon dioxide (), methane (), nitrous oxide (), and ozone (). Without greenhouse gases, the average temperature of Earth#Surface, Earth's surface would be about , rather than the present average of . The atmospheres of atmosphere of Venus, Venus, atmosphere of Mars, Mars and atmosphere of Titan, Titan also contain greenhouse gases. Human activities since the beginning of the Industrial Revolution (around 1750) have increased the Carbon dioxide in Earth's atmosphere, atmospheric concentration of carbon dioxide by over 50%, from 280 parts per million, ppm in 1750 to 421 ppm in 2022. The last time the atmospheric concentration of carbon dioxide was this high was over 3&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, volatile, colourless, flammable liquid with a distinctive alcoholic odour similar to that of ethanol (potable alcohol). A polar solvent, methanol acquired the name wood alcohol because it was once produced chiefly by the destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl benzoate, anisole, peroxyacids, as well as a host of more specialised chemicals. Occurrence Small amounts of methanol are present in normal, healthy hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Mass Units
The dalton or unified atomic mass unit (symbols: Da or u) is a non-SI unit of mass widely used in physics and chemistry. It is defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. The atomic mass constant, denoted ''m''u, is defined identically, giving . This unit is commonly used in physics and chemistry to express the mass of atomic-scale objects, such as atoms, molecules, and elementary particles, both for discrete instances and multiple types of ensemble averages. For example, an atom of helium-4 has a mass of . This is an intrinsic property of the isotope and all helium-4 atoms have the same mass. Acetylsalicylic acid (aspirin), , has an average mass of approximately . However, there are no acetylsalicylic acid molecules with this mass. The two most common masses of individual acetylsalicylic acid molecules are , having the most common isotopes, and , in which one carbon is carbon-13. The molecular mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluorinated Compounds
A perfluorinated compound (PFC) or perfluoro compound is an organofluorine compound containing only carbon-fluorines and C−C bonds, as well as potentially heteroatoms. Perfluorinated compounds have properties that result from the presence of fluorocarbons (containing only C−F and C−C bonds) and any functional group. Common functional groups in PFCs are OH, CO2H, chlorine, O, and SO3H. Electrofluorination is the predominant method of production. Some of these compounds known as perfluoroalkanes can remain in our atmosphere for a long time. They bioaccumulate due to their chemical stability. Because of their potential contribution to climate change, they were regulated under the Kyoto Protocol. Some fluorosurfactants have proven toxic in animal testing while widespread industrial applications continue. Applications Perfluorinated compounds are used ubiquitously: For example, fluorosurfactants are widely used in the production of teflon (PTFE) and related fluorinated po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Warming Potential
Global warming potential (GWP) is the heat absorbed by any greenhouse gas in the atmosphere, as a multiple of the heat that would be absorbed by the same mass of carbon dioxide (). GWP is 1 for . For other gases it depends on the gas and the time frame. Carbon dioxide equivalent (e or eq or -e) is calculated from GWP. For any gas, it is the mass of that would warm the earth as much as the mass of that gas. Thus it provides a common scale for measuring the climate effects of different gases. It is calculated as GWP times mass of the other gas. Methane has GWP (over 100 years) of 27.9 meaning that, for example, a leak of a tonne of methane is equivalent to emitting 27.9 tonnes of carbon dioxide. Similarly a tonne of nitrous oxide, from manure for example, is equivalent to 273 tonnes of carbon dioxide. Values Carbon dioxide is the reference. It has a GWP of 1 regardless of the time period used. emissions cause increases in atmospheric concentrations of that will last thousands ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Hexafluoride
Sulfur hexafluoride or sulphur hexafluoride (British spelling) is an inorganic compound with the formula SF6. It is a colorless, odorless, non- flammable, and non-toxic gas. has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule. Typical for a nonpolar gas, is poorly soluble in water but quite soluble in nonpolar organic solvents. It has a density of 6.12 g/L at sea level conditions, considerably higher than the density of air (1.225 g/L). It is generally transported as a liquefied compressed gas. is 23,500 times more potent than as a greenhouse gas but exists in relatively minor concentrations in the atmosphere. Its concentration in Earth's troposphere reached 10.63 parts per trillion (ppt) in 2021, rising at 0.39 ppt/year. The increase over the prior 40 years was driven in large part by the expanding electric power sector, including fugitive emissions from banks of gas contained in its med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mother Jones (magazine)
''Mother Jones'' (abbreviated ''MoJo'') is an American progressive magazine that focuses on news, commentary, and investigative journalism on topics including politics, environment, human rights, health and culture. Clara Jeffery serves as editor-in-chief of the magazine. Monika Bauerlein has been the CEO since 2015. ''Mother Jones'' is published by the Foundation for National Progress. The magazine was named after Mary Harris Jones, known as Mother Jones, an Irish-American trade union activist, socialist advocate, and ardent opponent of child labor. History For the first five years after its inception in 1976, ''Mother Jones'' operated with an editorial board, and members of the board took turns serving as managing editor for one-year terms. People who served on the editorial team during those years included Adam Hochschild, Paul Jacobs, Richard Parker, Deborah Johnson, Jeffrey Bruce Klein, Mark Dowie, Amanda Spake, Zina Klapper, and Deirdre English. According to Hochschil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Guardian
''The Guardian'' is a British daily newspaper. It was founded in 1821 as ''The Manchester Guardian'', and changed its name in 1959. Along with its sister papers ''The Observer'' and ''The Guardian Weekly'', ''The Guardian'' is part of the Guardian Media Group, owned by the Scott Trust. The trust was created in 1936 to "secure the financial and editorial independence of ''The Guardian'' in perpetuity and to safeguard the journalistic freedom and liberal values of ''The Guardian'' free from commercial or political interference". The trust was converted into a limited company in 2008, with a constitution written so as to maintain for ''The Guardian'' the same protections as were built into the structure of the Scott Trust by its creators. Profits are reinvested in journalism rather than distributed to owners or shareholders. It is considered a newspaper of record in the UK. The editor-in-chief Katharine Viner succeeded Alan Rusbridger in 2015. Since 2018, the paper's main news ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transparent to visible light but absorbs infrared radiation, acting as a greenhouse gas. It is a trace gas in Earth's atmosphere at 421 parts per million (ppm), or about 0.04% by volume (as of May 2022), having risen from pre-industrial levels of 280 ppm. Burning fossil fuels is the primary cause of these increased CO2 concentrations and also the primary cause of climate change.IPCC (2022Summary for policy makersiClimate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA Carbon dioxide is soluble in water and is found in groundwater, lakes, ice caps, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Spectrometry
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a type of plot of the ion signal as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. In a typical MS procedure, a sample, which may be solid, liquid, or gaseous, is ionized, for example by bombarding it with a beam of electrons. This may cause some of the sample's molecules to break up into positively charged fragments or simply become positively charged without fragmenting. These ions (fragments) are then separated accordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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