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  • aromatic
  • It can also be used as the synthetic solvent for polyamide, polyimide and polysulfone resin as well as the extraction solvents for aromatic hydrocarbon and butadiene extraction solvents and solvents for synthesizing chlorofluoroaniline. (chemicalbook.com)
  • used as an ornamental stone since the Upper Palaeolithic Sub-bituminous coal, whose properties range between those of lignite and those of bituminous coal (It is used primarily as fuel for steam-electric power generation and is also an important source of light aromatic hydrocarbons for the chemical synthesis industry. (wikipedia.org)
  • atom
  • As the only neutral atom for which the Schrödinger equation can be solved analytically, study of the energetics and bonding of the hydrogen atom has played a key role in the development of quantum mechanics. (wikipedia.org)
  • The ground state energy level of the electron in a hydrogen atom is −13.6 eV, which is equivalent to an ultraviolet photon of roughly 91 nm wavelength. (wikipedia.org)
  • The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, which conceptualizes the electron as "orbiting" the proton in analogy to the Earth's orbit of the Sun. However, the atomic electron and proton are held together by electromagnetic force, while planets and celestial objects are held by gravity. (wikipedia.org)
  • A more accurate description of the hydrogen atom comes from a purely quantum mechanical treatment that uses the Schrödinger equation, Dirac equation or even the Feynman path integral formulation to calculate the probability density of the electron around the proton. (wikipedia.org)
  • The common reaction in which it unites with another substance is called oxidation (see oxidation and reduction oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. (thefreedictionary.com)
  • CH4 + H2O → CO + 3 H2 In a second stage, additional hydrogen is generated through the lower-temperature, exothermic, water gas shift reaction, performed at about 360 °C: CO + H2O → CO2 + H2 Essentially, the oxygen (O) atom is stripped from the additional water (steam) to oxidize CO to CO2. (wikipedia.org)
  • In the oxidative half-reaction, the reduced cofactor reacts with molecular oxygen to form a C4a-hydroperoxyflavin intermediate, which transfers an oxygen atom to ornithine. (jove.com)
  • steam
  • Currently the dominant technology for direct production is steam reforming from hydrocarbons. (wikipedia.org)
  • Carbon dioxide can be separated from natural gas with a 60-70% efficiency for hydrogen production and from other hydrocarbons to varying degrees of efficiency.Specifically, bulk hydrogen is usually produced by the steam reforming of methane or natural gas. (wikipedia.org)
  • This can deliver benefits for an oil refinery because it is more efficient than separate hydrogen, steam and power plants. (wikipedia.org)
  • As a toxic gas that leaves no residue on items it contacts, ethylene oxide is a surface disinfectant that is widely used in hospitals and the medical equipment industry to replace steam in the sterilization of heat-sensitive tools and equipment, such as disposable plastic syringes. (wikipedia.org)
  • bonds
  • Water molecules form hydrogen bonds with each other and are strongly polar. (wikipedia.org)
  • The molecules of water are constantly moving in relation to each other, and the hydrogen bonds are continually breaking and reforming at timescales faster than 200 femtoseconds (2×10−13 seconds). (wikipedia.org)
  • The relative instability of the carbon-oxygen bonds in the molecule is revealed by the comparison in the table of the energy required to break two C-O bonds in the ethylene oxide or one C-O bond in ethanol and dimethyl ether: This instability correlates with its high reactivity, explaining the ease of its ring-opening reactions (see Chemical properties). (wikipedia.org)
  • yield
  • anaerobic digestion - the biological degradation of organic materials in the absence of oxygen to yield methane gas (that may be combusted to produce energy) and stabilised organic residues (that may be used as a soil additive). (wikipedia.org)
  • additive
  • Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. (wikipedia.org)
  • comprises
  • 10. A process as claimed in claim 1 , wherein the combining step c) comprises the step of adding to the solution of bicarbonate ions and hydrogen ions obtained in step b) an electron donor. (google.es)
  • wherein
  • 3. A process as claimed in claim 2 , wherein said hydration of step b) is catalysed by means of an enzyme capable of catalysing the hydration of dissolved CO 2 into hydrogen ions and bicarbonate ions. (google.es)
  • 7. A process as claimed in claim 1 , wherein the hydrogen fuel cell also generates, in step d), water that is recycled and used in the catalysing step b). (google.es)
  • catalyst
  • The Titan surface is also so cold that a chemical process that involved a catalyst would be needed to convert hydrogen molecules and acetylene back to methane, even though overall there would be a net release of energy. (nasa.gov)
  • reaction
  • Hydrogen gas was first artificially produced in the early 16th century by the reaction of acids on metals. (wikipedia.org)
  • The resulting endothermic reaction breaks up the methane molecules and forms carbon monoxide CO and hydrogen H2. (wikipedia.org)
  • Like the previous process, the formation of hydrogen from oil is done with a water-gas shift reaction. (wikipedia.org)
  • Finally, water, a by-product of the oxidizing reaction of the hydrogen fuel cell, is recovered and recycled back into the aqueous enzymatic system. (google.es)
  • The carbon dioxide is allowed to escape and air is prevented from entering the reaction vessel to stop oxygen oxidising ethanol to ethanoic acid ('acetic acid' or vinegar! (docbrown.info)
  • dimethyl sulfoxide is widely used as solvents and reagents, particularly as the processing reagent and spinning solvent at the reaction of acrylonitrile polymerization used for polyurethane synthesis and the spinning solvent. (chemicalbook.com)
  • chemically
  • I didn't expect this result, because molecular hydrogen is extremely chemically inert in the atmosphere, very light and buoyant. (nasa.gov)
  • Chemically, water is a compound of hydrogen and oxygen, having the formula H 2 O. It is chemically active, reacting with certain metals and metal oxides to form bases, and with certain oxides of nonmetals to form acids. (thefreedictionary.com)
  • ultraviolet
  • The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F). Pure hydrogen-oxygen flames emit ultraviolet light and with high oxygen mix are nearly invisible to the naked eye, as illustrated by the faint plume of the Space Shuttle Main Engine, compared to the highly visible plume of a Space Shuttle Solid Rocket Booster, which uses an ammonium perchlorate composite. (wikipedia.org)
  • electron
  • The asymmetrical shape of the molecule arises from a tendency of the four electron pairs in the valence shell of oxygen to arrange themselves symmetrically at the vertices of a tetrahedron around the oxygen nucleus. (thefreedictionary.com)
  • adsorption
  • c) passing a hydrocarbon feedstream comprising hydrocarbons to said adsorption zone after adsorption of said material at desorption conditions to desorb said material from said adsorbent and produce at least a portion of said first stream. (google.com)
  • ammonia
  • Most hydrogen is used near the site of its production, the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia production, mostly for the fertilizer market. (wikipedia.org)
  • Water has a very high specific heat capacity of 4.1814 J/(g·K) at 25 °C - the second highest among all the heteroatomic species (after ammonia), as well as a high heat of vaporization (40.65 kJ/mol or 2257 kJ/kg at the normal boiling point), both of which are a result of the extensive hydrogen bonding between its molecules. (wikipedia.org)
  • degrees
  • On Titan, where temperatures are around 90 Kelvin (minus 290 degrees Fahrenheit), a methane-based organism would have to use a substance that is liquid as its medium for living processes, but not water itself. (nasa.gov)
  • water
  • Scientists have not yet detected this form of life anywhere, though there are liquid-water-based microbes on Earth that thrive on methane or produce it as a waste product. (nasa.gov)
  • While liquid water is widely regarded as necessary for life, there has been extensive speculation published in the scientific literature that this is not a strict requirement. (nasa.gov)
  • They take up simple substances such as water, carbon dioxide, and oxygen, as well as inorganic nutrients and produce biological molecules needed for life from the inorganic substances. (scribd.com)
  • Because of hydrogen bonding between water molecules, the latent heats latent heat, heat change associated with a change of state or phase (see states of matter). (thefreedictionary.com)
  • The accepted IUPAC name of water is oxidane or simply water,or its equivalent in different languages, although there are other systematic names which can be used to describe the molecule. (wikipedia.org)
  • Other systematic names for water include hydroxic acid, hydroxylic acid, and hydrogen hydroxide, using acid and base names. (wikipedia.org)
  • The polarized form of the water molecule, H+ OH− , is also called hydron hydroxide by IUPAC nomenclature. (wikipedia.org)
  • 20/30/10 standard - 20 mg/l Biochemical Oxygen Demand (BOD), 30 mg/l Suspended Solids (SS), 10 units of E. coli: the water quality standard for greywater use in toilets, laundry and surface irrigation. (wikipedia.org)
  • form
  • The new hydrogen findings are consistent with conditions that could produce an exotic, methane-based life form, but do not definitively prove its existence, said Darrell Strobel, a Cassini interdisciplinary scientist based at Johns Hopkins University in Baltimore, Md., who authored the paper on hydrogen. (nasa.gov)
  • Ozone ozone , an allotropic form of the chemical element oxygen (see allotropy). (thefreedictionary.com)
  • Its monatomic form (H) is the most abundant chemical substance in the Universe , constituting roughly 75% of all baryonic mass. [note Non- remnant stars are mainly composed of hydrogen in the plasma state . (wikipedia.org)
  • One form of the fuel known as RP-1 is burned with liquid oxygen as rocket fuel. (wikipedia.org)
  • Its hydrogen bonding causes its many unique properties, such as having a solid form less dense than its liquid form, a relatively high boiling point of 100 °C for its molar mass, and a high heat capacity. (wikipedia.org)
  • production
  • Resource efficiency reflects the understanding that current, global, economic growth and development can not be sustained with the current production and consumption patterns. (wikipedia.org)
  • page needed] Resource efficiency is the reduction of the environmental impact from the production and consumption of these goods, from final raw material extraction to last use and disposal. (wikipedia.org)
  • Hydrogen production is the family of industrial methods for generating hydrogen. (wikipedia.org)
  • In 2006, the United States was estimated to have a production capacity of 11 million tons of hydrogen. (wikipedia.org)
  • Hydrogen production is an estimated $100 billion industry. (wikipedia.org)
  • There are no natural hydrogen deposits, and for this reason the production of hydrogen plays a key role in modern society. (wikipedia.org)
  • which account for 48%, 30% 18% and 4% of the world's hydrogen production respectively. (wikipedia.org)
  • The production of hydrogen from natural gas is the cheapest source of hydrogen currently. (wikipedia.org)
  • The object of the invention is the coupling of a hydrogen fuel cell to an enzymatic process for the production of electricity and the transformation and sequestration of CO2. (google.es)
  • Various observers advocate hydrocarbon liquefaction to provide everything from a minor role to production levels of several million barrels per day. (royalsocietypublishing.org)
  • Capturing CO2 is most effective at point sources, such as large fossil fuel or biomass energy facilities, industries with major CO2 emissions, natural gas processing, synthetic fuel plants and fossil fuel-based hydrogen production plants. (wikipedia.org)
  • gases
  • An alkali anion exchange membrane (AAEM) is a semipermeable membrane generally made from ionomers and designed to conduct anions while being impermeable to gases such as oxygen or hydrogen. (wikipedia.org)
  • Depending on the quality of the feedstock (natural gas, rich gases, naphtha, etc.), one ton of hydrogen produced will also produce 9 to 12 tons of CO2. (wikipedia.org)