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Asphaltene
Asphaltenes are molecular substances that are found in crude oil, along with resins, aromatic hydrocarbons, and saturates (i.e. saturated hydrocarbons such as alkanes). The word "asphaltene" was coined by Jean-Baptiste Boussingault in 1837 when he noticed that the distillation residue of some bitumens had asphalt-like properties. Asphaltenes in the form of asphalt or bitumen products from oil refineries are used as paving materials on roads, shingles for roofs, and waterproof coatings on building foundations. Composition Asphaltenes consist primarily of carbon, hydrogen, nitrogen, oxygen, and sulfur, as well as trace amounts of vanadium and nickel. The C:H ratio is approximately 1:1.2, depending on the asphaltene source. Asphaltenes are defined operationally as the n- heptane ()-insoluble, toluene ()-soluble component of a carbonaceous material such as crude oil, bitumen, or coal. Asphaltenes have been shown to have a distribution of molecular masses in the range of 400 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Paramagnetic Resonance
Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spins excited are those of the electrons instead of the atomic nuclei. EPR spectroscopy is particularly useful for studying metal complexes and organic radicals. EPR was first observed in Kazan State University by Soviet physicist Yevgeny Zavoisky in 1944, and was developed independently at the same time by Brebis Bleaney at the University of Oxford. Theory Origin of an EPR signal Every electron has a magnetic moment and spin quantum number s = \tfrac , with magnetic components m_\mathrm = + \tfrac or m_\mathrm = - \tfrac . In the presence of an external magnetic field with strength B_\mathrm , the electron's magnetic moment aligns itself either antiparallel ( m_\mathrm = - \tfrac ) or parallel ( m_\mathrm = + \tfrac ) to the fie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitumen
Bitumen ( , ) is an immensely viscosity, viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the material is commonly referred to as asphalt or tar. Whether found in natural deposits or refined from petroleum, the substance is classed as a pitch (resin), pitch. Prior to the 20th century, the term asphaltum was in general use. The word derives from the Ancient Greek word (), which referred to natural bitumen or pitch. The largest natural deposit of bitumen in the world is the Pitch Lake of southwest Trinidad, which is estimated to contain 10 million tons. About 70% of annual bitumen production is destined for road surface, road construction, its primary use. In this application, bitumen is used to bind construction aggregate, aggregate particles like gravel and forms a substance referred to as asphalt concrete, which is collo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturate, Aromatic, Resin And Asphaltene
Saturate, Aromatic, Resin and Asphaltene (SARA) is an analysis method that divides crude oil components according to their polarizability and polarity. The saturate fraction consists of nonpolar material including linear, branched, and cyclic saturated hydrocarbons ( paraffins). Aromatics, which contain one or more aromatic rings, are slightly more polarizable. The remaining two fractions, resins and asphaltenes, have polar substituents. The distinction between the two is that asphaltenes are insoluble in an excess of heptane (or pentane) whereas resins are miscible with heptane (or pentane). Method description There are three main methods to obtain SARA results. One has lately emerged as the most popular. That technology is known as the Iatroscan TLC-FID, and it combines thin-layer chromatography (TLC) with flame ionization detection (FID). It is referred to as IP-143. Other analysis giving SARA numbers might not correspond to the numbers obtained in IP-143. It is therefo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitumen
Bitumen ( , ) is an immensely viscosity, viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the material is commonly referred to as asphalt or tar. Whether found in natural deposits or refined from petroleum, the substance is classed as a pitch (resin), pitch. Prior to the 20th century, the term asphaltum was in general use. The word derives from the Ancient Greek word (), which referred to natural bitumen or pitch. The largest natural deposit of bitumen in the world is the Pitch Lake of southwest Trinidad, which is estimated to contain 10 million tons. About 70% of annual bitumen production is destined for road surface, road construction, its primary use. In this application, bitumen is used to bind construction aggregate, aggregate particles like gravel and forms a substance referred to as asphalt concrete, which is collo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Refineries
An oil refinery or petroleum refinery is an industrial process plant where petroleum (crude oil) is transformed and refined into products such as gasoline (petrol), diesel fuel, asphalt base, fuel oils, heating oil, kerosene, liquefied petroleum gas and petroleum naphtha. Petrochemical feedstock like ethylene and propylene can also be produced directly by cracking crude oil without the need of using refined products of crude oil such as naphtha. The crude oil feedstock has typically been processed by an oil production plant. There is usually an oil depot at or near an oil refinery for the storage of incoming crude oil feedstock as well as bulk liquid products. In 2020, the total capacity of global refineries for crude oil was about 101.2 million barrels per day. Oil refineries are typically large, sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units, such as distillation columns. In m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is a type of fossil fuel, formed when dead plant matter decays into peat which is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian (geology), Pennsylvanian) and Permian times. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its Electricity generation, electricity. Some iron and steel-maki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Masses
The molecular mass () is the mass of a given molecule, often expressed in units of daltons (Da). Different molecules of the same compound may have different molecular masses because they contain different isotopes of an element. The derived quantity relative molecular mass is the unitless ratio of the mass of a molecule to the atomic mass constant (which is equal to one dalton). The molecular mass and relative molecular mass are distinct from but related to the ''molar mass''. The molar mass is defined as the mass of a given substance divided by the amount of the substance, and is expressed in grams per mole (g/mol). That makes the molar mass an ''average'' of many particles or molecules (weighted by abundance of the isotopes), and the molecular mass the mass of one specific particle or molecule. The molar mass is usually the more appropriate quantity when dealing with macroscopic (weigh-able) quantities of a substance. The definition of molecular weight is most authoritativel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Mass Unit
The dalton or unified atomic mass unit (symbols: Da or u, respectively) is a unit of mass defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. It is a non-SI unit accepted for use with SI. The word "unified" emphasizes that the definition was accepted by both IUPAP and IUPAC. The atomic mass constant, denoted , is defined identically. Expressed in terms of , the atomic mass of carbon-12: . Its value in SI units is an experimentally determined quantity. The 2022 CODATA recommended value of the atomic mass constant expressed in the SI base unit kilogram is:This value serves as a conversion factor of mass from daltons to kilograms, which can easily be converted to grams and other metric units of mass. The 2019 revision of the SI redefined the kilogram by fixing the value of the Planck constant (), improving the precision of the atomic mass constant expressed in SI units by anchoring it to fixed physica ... [...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 ionization, ionized, for example by bombarding it with a Electron ionization, 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 (fragmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecule
A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, and biochemistry, the distinction from ions is dropped and ''molecule'' is often used when referring to polyatomic ions. A molecule may be homonuclear, that is, it consists of atoms of one chemical element, e.g. two atoms in the oxygen molecule (O2); or it may be heteronuclear, a chemical compound composed of more than one element, e.g. water (molecule), water (two hydrogen atoms and one oxygen atom; H2O). In the kinetic theory of gases, the term ''molecule'' is often used for any gaseous particle regardless of its composition. This relaxes the requirement that a molecule contains two or more atoms, since the noble gases are individual atoms. Atoms and complexes connected by non-covalent interactions, such as hydrogen bonds or ionic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptane
Heptane or ''n''-heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 point is 100% iso-octane). Octane number equates to the anti-knock qualities of a comparison mixture of heptane and iso-octane which is expressed as the percentage of iso-octane in heptane, and is listed on pumps for gasoline (petrol) dispensed globally. History Normal heptane was discovered in 1862 by Carl Schorlemmer, who, while analyzing pyrolysis products of the cannel coal mined in Wigan, identified, separated by fractional distillation and studied a series of liquid hydrocarbons inert to nitric and sulfuric acids. One of them, which he called hydride of heptyl (oenanthyl), had an empirical formula of C7H16, density of 0.709 at 18 °C and boiled between 98 and 99 °C. In the next year he identified the same compound in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Magnetic Resonance
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca. 20 tesla, the frequency is similar to VHF and UHF television broadcasts (60–1000 MHz). NMR results from specific magnetic properties of certain atomic nuclei. High-resolution nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics and crystals as well as non-crysta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
