Sketch of the working principle of a xenon dual-phase TPC The XENON experiment operates a dual phase time projection chamber (TPC), which utilizes a liquid xenon target with a gaseous phase on top. Two arrays of photomultiplier tubes (PMTs), one at the top of the detector in the gaseous phase (GXe), and one at the bottom of the liquid layer (LXe), detect scintillation and electroluminescence light produced when charged particles interact in the detector. Electric fields are applied across both the liquid and gaseous phase of the detector. The electric field in the gaseous phase has to be sufficiently large to extract electrons from the liquid phase.
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The thermal conductivity through bulk materials in porous or granular form is governed by the type of gas in the gaseous phase, and its pressure. At lower pressures, the thermal conductivity of a gaseous phase is reduced, with this behaviour governed by the Knudsen number, defined as K_n=l/d, where l is the mean free path of gas molecules and d is the typical gap size of the space filled by the gas. In a granular material d corresponds to the characteristic size of the gaseous phase in the pores or intergranular spaces.
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Liquid marbles are not hermetically coated by solid particles but connected to the gaseous phase. Kinetics of the evaporation of liquid marbles has been investigated.
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During the study of the reaction of hydrocarbon chlorination, he determined the constants of the elemental reaction speed in the gaseous phase, based on which the relation between the substance structure and the ability to react was found. Study of reaction in hydrogen and bromine in the gaseous phase experimentally proved the achievements of the kinetics school in the field of ignition and burning. He discovered the instability of the flame front and established its theory (1951).
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Gas diffusion electrodes (GDE) are electrodes with a conjunction of a solid, liquid and gaseous interface, and an electrical conducting catalyst supporting an electrochemical reaction between the liquid and the gaseous phase.
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A study on the anionic oxy-Cope rearrangement carried out entirely in the gaseous phase reported that the rate enhancement stems not from solvent interactions, but from those within the structure itself.
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Such methane transforms into the gaseous phase and seeps into the ocean at this site, which has been a popular location of study since its discovery in 1986. Hydrate Ridge also supports a methane-driven benthic community.
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The resulting temperature pulsations in the gaseous phase are the prime cause of the pressure changes there. The amplitude of the traveling thermal wave decreases strongly (exponentially) along its propagation direction, but if its propagation distance in the condensed phase is not too long, its amplitude near the gaseous phase is sufficient to create detectable pressure changes. This property of the thermal wave confers unique features to the detection of light absorption by the photoacoustic method. The temperature and pressure changes involved are minute, compared to everyday scale – typical order of magnitude for the temperature changes, using ordinary light intensities, is about micro- to millidegrees and for the resulting pressure changes is about nano- to microbars.
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From here, adsorbate molecules would either adsorb to the adsorbent or desorb into the gaseous phase. The probability of adsorption occurring from the precursor state is dependent on the adsorbate’s proximity to other adsorbate molecules that have already been adsorbed. If the adsorbate molecule in the precursor state is in close proximity to an adsorbate molecule that has already formed on the surface, it has a sticking probability reflected by the size of the SE constant and will either be adsorbed from the precursor state at a rate of kEC or will desorb into the gaseous phase at a rate of kES. If an adsorbate molecule enters the precursor state at a location that is remote from any other previously adsorbed adsorbate molecules, the sticking probability is reflected by the size of the SD constant.
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Selenium in SeF4 has an oxidation state of +4. Its shape in the gaseous phase is similar to that of SF4, having a see-saw shape. VSEPR theory predicts a pseudo-trigonal pyramidal disposition of the five electron pairs around the selenium atom. The axial Se-F bonds are 177 pm with an F-Se-F bond angle of 169.2°.
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Condensation is initiated by the formation of atomic/molecular clusters of that species within its gaseous volume—like rain drop or snow flake formation within clouds—or at the contact between such gaseous phase and a liquid or solid surface. In clouds, this can be catalyzed by water- nucleating proteins, produced by atmospheric microbes, which are capable of binding gaseous or liquid water molecules.
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It does not make cigarettes less unhealthy. The filter may be made from cellulose acetate fibre, paper or activated charcoal (either as a cavity filter or embedded into the cellulose acetate). Macroporous phenol-formaldehyde resins and asbestos have also been used in cigarette filters. The acetate and paper modify the particulate smoke phase by particle retention (filtration), and finely divided carbon modifies the gaseous phase (adsorption).
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Diagram of a binding curve RIfS is used especially as a detection method in chemo- and biosensors. Chemosensors are particularly suitable for measurements under difficult conditions and in the gaseous phase. As sensitive layers, mostly non-selective measuring polymers are used which sort the analytes according to size (the so- called molecular sieve effect when using microporous polymers) or according to polarity (e.g. functionalized polydimethylsiloxanes).
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The temperature dependence of the soil hydraulic properties was included by considering the effects of temperature on surface tension, dynamic viscosity and the density of water. The heat transport equation in CHAIN_2D considered transport due to conduction and advection with flowing water. The solute transport equations considered advective-dispersive transport in the liquid phase, as well as diffusion in the gaseous phase. The transport equations also included provisions for nonlinear nonequilibrium reactions between the solid and liquid phases, linear equilibrium reactions between the liquid and gaseous phase, zero-order production and two first- order degradation reactions: one which was independent of other solutes, and one which provided the coupling between solutes involved in the sequential first-order decay reactions. The SWMS_2D and CHAIN_2D models formed the bases of versions 1.0 (for 16-bit Windows 3.1) and 2.0 (for 32-bit Windows 95) of HYDRUS-2D (Šimůnek et al.
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Most modern breweries utilize vacuum evaporation to reduce the boiling temperature and maintain flavor. In essence, the beer is placed under a light vacuum to facilitate the alcohol molecules going into the gaseous phase. If a sufficient vacuum is applied, it is not necessary to "cook" the beer at a temperature that destroys the flavor. Some heat must nevertheless be supplied to counter the heat lost to enthalpy of vaporization.
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Above this zone methane is only present in its dissolved form at concentrations that decrease towards the sediment surface. Below it, methane is gaseous. At Blake Ridge on the Atlantic continental rise, the GHSZ started at 190 m depth and continued to 450 m, where it reached equilibrium with the gaseous phase. Measurements indicated that methane occupied 0-9% by volume in the GHSZ, and ~12% in the gaseous zone.
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Water must be absent otherwise there will be a side product of a halohydrin. The reaction is necessarily to be carried out in a dry inert solvent such as or directly in the gaseous phase. The reaction of alkynes are similar, with the product being a geminal dihalide; once again, Markovnikov's rule is followed. Alkenes also react with halogens (X2) to form haloalkanes with two neighboring halogen atoms in a halogen addition reaction.
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MLIS operates in cascade setup, like the gaseous diffusion process. Instead of vaporized uranium as in AVLIS the working medium of the MLIS is uranium hexafluoride which requires a much lower temperature to vaporize. The UF6 gas is mixed with a suitable carrier gas (a noble gas including some hydrogen) which allows the molecules to remain in the gaseous phase after being cooled by expansion through a supersonic de Laval nozzle. A scavenger gas (e.g.
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Electron-beam physical vapor deposition, or EBPVD, is a form of physical vapor deposition in which a target anode is bombarded with an electron beam given off by a charged tungsten filament under high vacuum. The electron beam causes atoms from the target to transform into the gaseous phase. These atoms then precipitate into solid form, coating everything in the vacuum chamber (within line of sight) with a thin layer of the anode material.
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Dinitrile polymers formed from the condensation of dinitrile with decaborane satisfy these criteria. Chemical vapor deposition (CVD) of titanium and zirconium diborides is another method for preparing coatings of UHTCs. These techniques rely on metal halide and boron halide precursors (such as TiCl4 and BCl3) in the gaseous phase and use H2 as a reducing agent. This synthesis route can be employed at low temperatures and produces thin films for coating on metal (and other material) surfaces.
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Since the process requires additional energy, it is an endothermic change. The enthalpy of sublimation (also called heat of sublimation) can be calculated by adding the enthalpy of fusion and the enthalpy of vaporization. Comparison of phase diagrams of carbon dioxide (red) and water (blue) showing the carbon dioxide sublimation point (middle-left) at 1 atmosphere. As dry ice is heated, it crosses this point along the bold horizontal line from the solid phase directly into the gaseous phase.
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The hydrocarbon dew point is the temperature (at a given pressure) at which the hydrocarbon components of any hydrocarbon-rich gas mixture, such as natural gas, will start to condense out of the gaseous phase. It is often also referred to as the HDP or the HCDP. The maximum temperature at which such condensation takes place is called the cricondentherm.Hydrocarbon Dew Point The hydrocarbon dew point is a function of the gas composition as well as the pressure.
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In this case food is flash frozen and put into a reduced-pressure system which causes the water to sublimate directly from the solid to the gaseous phase. Although freeze-drying is more expensive than traditional dehydration techniques, it also mitigates the change in flavor, texture, and nutritional value. In addition, another widely used industrial method of drying of food is convective hot air drying. Industrial hot air dryers are simple and easy to design, construct and maintain.
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Spectrophotometry in infrared light is mainly used to study structure of substances, as given groups give absorption at defined wavelengths. Measurement in aqueous solution is generally not possible, as water absorbs infrared light strongly in some wavelength ranges. Therefore, infrared spectroscopy is either performed in the gaseous phase (for volatile substances) or with the substances pressed into tablets together with salts that are transparent in the infrared range. Potassium bromide (KBr) is commonly used for this purpose.
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Depleted uranium dioxide can be also used as a catalyst, e.g. for degradation of volatile organic compounds in gaseous phase, oxidation of methane to methanol, and removal of sulfur from petroleum. It has high efficiency and long-term stability when used to destroy VOCs when compared with some of the commercial catalysts, such as precious metals, TiO2, and Co3O4 catalysts. Much research is being done in this area, DU being favoured for the uranium component due to its low radioactivity.
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Production methods for these materials can be divided into powder and crystal growth based techniques. Powder based techniques offer excellent ability to control and maintain desired carrier distribution, particle size, and composition. In crystal growth techniques dopants are often mixed with melt, but diffusion from gaseous phase can also be used. In the zone melting techniques disks of different materials are stacked on top of others and then materials are mixed with each other when a traveling heater causes melting.
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Within the Earth's atmosphere and surface, the liquid phase is the most common and is the form that is generally denoted by the word "water". The solid phase of water is known as ice and commonly takes the structure of hard, amalgamated crystals, such as ice cubes, or loosely accumulated granular crystals, like snow. Aside from common hexagonal crystalline ice, other crystalline and amorphous phases of ice are known. The gaseous phase of water is known as water vapor (or steam).
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These high molecular weight compounds then precipitate from gaseous phase, forming conductive or non-conductive deposits on the electrodes and insulating surfaces of the detector and distorting its response. Gases containing hydrocarbon quenchers, e.g. argon–methane, are typically sensitive to aging by polymerization; addition of oxygen tends to lower the aging rates. Trace amounts of silicone oils, present from outgassing of silicone elastomers and especially from traces of silicone lubricants, tend to decompose and form deposits of silicon crystals on the surfaces.
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The applied electric field prevents recombination of all the electrons produced from a charged particle interaction in the TPC. These electrons are drifted to the top of the liquid phase by the electric field. The ionization is then extracted into the gas phase by the stronger electric field in the gaseous phase. The electric field accelerates the electrons to the point that it creates a proportional scintillation signal that is also collected by the PMTs, and is referred to as the S2 signal.
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In practical applications when looking at gases permeating metals, there is a way to relate gas pressure to concentration. Many gases exist as diatomic molecules when in the gaseous phase, but when permeating metals they exist in their singular ionic form. Sieverts' law states that the solubility of a gas, in the form of a diatomic molecule, in metal is proportional to the square root of the partial pressure of the gas. The flux can be approximated in this case by the equation :\bigg.
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Most thermodynamic cycles make use of the latent heat (advantages of phase change) of the working fluid. In case of other cycles the working fluid remains in gaseous phase while undergoing all the processes of the cycle. When it comes to heat engines, working fluid generally undergoes a combustion process as well, for example in internal combustion engines or gas turbines. There are also technologies in heat pump and refrigeration, where working fluid does not change phase, such as reverse Brayton or Stirling cycle.
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In the gas phase SnBr2 is non-linear with a bent configuration similar to SnCl2 in the gas phase. The Br-Sn-Br angle is 95° and the Sn-Br bond length is 255pm.J.L Wardell "Tin:Inorganic Chemistry" Encyclopedia of Inorganic Chemistry Ed: R Bruce King John Wiley & Sons (1994) There is evidence of dimerisation in the gaseous phase. The solid state structure is related to that of SnCl2 and PbCl2 and the tin atoms have five near bromine atom neighbours in an approximately trigonal bipyramidal configuration.
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While the photothermal mechanism is universal, there could exist additional other mechanisms, superimposed on the photothermal mechanism, which may contribute significantly to the photoacoustic signal. These mechanisms are generally related to photophysical processes and photochemical reactions following light absorption: (1) change in the material balance of the sample or the gaseous phase around the sample; (2) change in the molecular organization, which results in molecular volume changes.Schulenberg, C.P.J. and Braslavsky, S.E. (1997) "Time-Resolved Photothermal Studies with Biological Supramoleculear Systems", pp. 57–81 in Progress in Photothermal and Photoacoustic Science and Technology Vol. III.
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The gaseous phase no longer exerts significant pressure on the substance to be evaporated, and consequently, the rate of evaporation no longer depends on pressure. That is, because the continuum assumptions of fluid dynamics no longer apply, mass transport is governed by molecular dynamics rather than fluid dynamics. Thus, a short path between the hot surface and the cold surface is necessary, typically by suspending a hot plate covered with a film of feed next to a cold plate with a line of sight in between. Molecular distillation is used industrially for purification of oils.
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In 1931 Viktor Kokochashvili was appointed as the assistant professor on the chair of inorganic chemistry of the Chemistry-Technological Institute of Dnepropetrovsk. He was awarded with the degree of candidate of chemistry without defending the thesis in the field of studying photochemical reactions in gaseous phase. During 1953-1973 he has been working as an invariable head of the chair of physical chemistry at Ivane Javakhishvili Tbilisi State University. In 1943 he defended the PhD thesis on the following issue: "The study of the combustion of hydrogen and bromine mixtures".
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The gaseous phase no longer exerts significant pressure on the substance to be evaporated, and consequently, rate of evaporation no longer depends on pressure. That is, because the continuum assumptions of fluid dynamics no longer apply, mass transport is governed by molecular dynamics rather than fluid dynamics. Thus, a short path between the hot surface and the cold surface is necessary, typically by suspending a hot plate covered with a film of feed next to a cold plate with a line of sight in between. Molecular distillation is used industrially for purification of oils.
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Callander Bay is an eroded Proterozoic volcanic pipe formed by the violent, supersonic eruption of a deep-origin volcano. These volcanoes originate at least three times as deep as most other volcanoes, and the resulting magma that is pushed toward the surface is high in magnesium and volatile compounds such as water and carbon dioxide. As the body of magma rises toward the surface, the volatile compounds transform to gaseous phase as pressure is reduced with decreasing depth. This sudden expansion propels the magma upward at rapid speeds, resulting in a shallow supersonic eruption.
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Volcanic pipes form as the result of violent eruptions of deep-origin volcanoes. These volcanoes originate at least three times as deep as most other volcanoes, and the resulting magma that is pushed toward the surface is high in magnesium and volatile compounds such as water and carbon dioxide. As the body of magma rises toward the surface, the volatile compounds transform to gaseous phase as pressure is reduced with decreasing depth. This sudden expansion propels the magma upward at rapid speeds, resulting in a supersonic Plinian eruption.
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Carbon monoxide is a strong reductive agent, and whilst not known, it has been used in pyrometallurgy to reduce metals from ores since ancient times. Carbon monoxide strips oxygen off metal oxides, reducing them to pure metal in high temperatures, forming carbon dioxide in the process. Carbon monoxide is not usually supplied as is, in gaseous phase, in the reactor, but rather it is formed in high temperature in presence of oxygen-carrying ore, carboniferous agent such as coke and high temperature. The blast furnace process is a typical example of a process of reduction of metal from ore with carbon monoxide.
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AlF, AlCl, AlBr, and exist in the gaseous phase when the respective trihalide is heated with aluminium, and at cryogenic temperatures. Their instability in the condensed phase is due to their ready disproportionation to aluminium and the respective trihalide: the reverse reaction is favored at high temperature (although even then they are still short-lived), explaining why AlF3 is more volatile when heated in the presence of aluminium metal, as is aluminium metal when heated in the presence of AlCl3.Greenwood and Earnshaw, pp. 233–7 A stable derivative of aluminium monoiodide is the cyclic adduct formed with triethylamine, .
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Many metal foam manufacturing techniques are accomplished by the introduction of a gaseous phase into a precursor matrix, which can occur in either molten metal or a powdered metal form. Due to titanium's high melting point (1670 °C) and high chemical affinity with oxygen, nitrogen, carbon and hydrogen (which dissolve rapidly either in liquid or solid titanium at a temperature above 400 °C), solid-state processes based on powder densification are the preferred method of fabrication. Processing methods must also be designed to avoid exposure to air or moisture; vacuum or inert gas sintering processes are usually sufficient for preventing contamination.
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Boiling water is a classic example: The system starts with liquid water, and when enough heat has been added to the water, the water boils into the gaseous phase. While there has been a phase change, the water molecule, H2O hasn’t broken apart and is still present at the end of the reaction, so this is analogous to an extrinsic change. Electrolysis of water is a chemical change – electricity is used to break water into hydrogen and oxygen gas. Since the molecules present have been changed, this is a chemical change, similar to an intrinsic change.
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For nanofibers and nanoplates, the other dimensions may or may not be in the nanoscale, but must be significantly larger. A significant different in all cases is noted to be typically at least a factor of 3. Nanostructured materials are often categorized by what phases of matter they contain. A nanocomposite is a solid containing at least one physically or chemically distinct region, or collection of regions, having at least one dimension in the nanoscale.. A nanofoam has a liquid or solid matrix, filled with a gaseous phase, where one of the two phases has dimensions on the nanoscale.
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The oxidation of crushed particulate ores and the removal of sulfide, arsenic or other contaminants is a crucial separation process in the purification of metals which can be carried out within a FR. The oxidation of sulfide ores result in a conversion of small sized solid sulfide ore to oxides and residual sulfur dioxide gas culminating in a separation by converting unwanted sulfides into a gaseous phase. These contaminants can then go under post-treatment to create useful products from the waste stream, such as sulfuric acid using the contact process. The equation belowMarsden JO. Chemistry of Gold Extraction. House CI, editor.
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Most accurate results are obtained near the boiling point of substances and large errors result for measurements smaller than . Procedures often consist of purifying the test substance, isolating it in a container, evacuating any foreign gas, then measuring the equilibrium pressure of the gaseous phase of the substance in the container at different temperatures. Better accuracy is achieved when care is taken to ensure that the entire substance and its vapor are at the prescribed temperature. This is often done, as with the use of an isoteniscope, by submerging the containment area in a liquid bath.
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FID Schematic: A) Capillary tube; B) Platinum jet; C) Hydrogen; D) Air; E) Flame; F) Ions; G) Collector; H) Coaxial cable to analog- to-digital converter; J) Gas outlet The design of the flame ionization detector varies from manufacturer to manufacturer, but the principles are the same. Most commonly, the FID is attached to a gas chromatography system. The eluent exits the gas chromatography column (A) and enters the FID detector’s oven (B). The oven is needed to make sure that as soon as the eluent exits the column, it does not come out of the gaseous phase and deposit on the interface between the column and FID.
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3 Photoacoustic spectroscopy is also useful for the opposite case of opaque samples, where the absorption is essentially complete. In an arrangement where a sensor is placed in a gaseous phase above the sample and the light impinges the sample from above, the photoacoustic signal results from an absorption zone close to the surface. A typical parameter which governs the signal in this case is the "thermal diffusion length", which depends on the material and the modulation frequency and ordinarily is in the order of several micrometers. The signal is related to the light absorbed in the small distance of the thermal diffusion length, allowing the determination of the absorption spectrum.
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The supersonic separator requires a certain process scheme, which includes further auxiliary equipment and often forms a skid or processing block. The typical basic scheme for supersonic separation is an arrangement where the feed gas is pre-cooled in a heat exchanger by the dry stream of the separator unit. The liquid phase from the supersonic separator goes into a 2-phase or 3-phase separator, where the slip gas is separated from water and/or from liquid hydrocarbons. The gaseous phase of this secondary separator joins the dry gas of the supersonic separator, the liquids go for transport, storage or further processing and the water for treatment and disposal.
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Anyone employing an incubator shaker (thermal shaker) to grow yeast or bacteria in the laboratory needs to beware that under the usual conditions encountered in the lab, the rate at which oxygen diffuses from the gaseous phase into the shaken liquid phase is too slow to keep up with the rate at which the oxygen is consumed by for example E coli dividing every half hour or S cerevisiae dividing every hour. If the investigator measure the oxygen in the shake flask on the shaker -- polarographically, for example -- at mid-exponential phase of growth, the dissolved oxygen concentration will turn out to be zero.
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MO diagram of dimolybdenum A sextuple bond is a type of covalent bond involving 12 bonding electrons and in which the bond order is 6. The only known molecules with true sextuple bonds are the diatomic dimolybdenum (Mo2) and ditungsten (W2), which exist in the gaseous phase and have boiling points of and . There is strong evidence to believe that there is no element with atomic number below about 100 that can form a bond with a greater order than 6 between its atoms, but the question of possibility of such a bond between two atoms of different elements remains open. Bonds between heteronuclear systems with two atoms of different elements may not necessarily have the same limit.
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The processes in a flame include the stages of desolvation (drying) in which the solvent is evaporated and the dry sample nano-particles remain, vaporization (transfer to the gaseous phase) in which the solid particles are converted into gaseous molecule, atomization in which the molecules are dissociated into free atoms, and ionization where (depending on the ionization potential of the analyte atoms and the energy available in a particular flame) atoms may be in part converted to gaseous ions. Each of these stages includes the risk of interference in case the degree of phase transfer is different for the analyte in the calibration standard and in the sample. Ionization is generally undesirable, as it reduces the number of atoms that are available for measurement, i.e., the sensitivity.
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The heat transport equation considers conduction as well as advection with flowing water. The solute transport equations assume advective-dispersive transport in the liquid phase, and diffusion in the gaseous phase. The transport equations further include provisions for nonlinear and/or non-equilibrium reactions between the solid and liquid phases, linear equilibrium reactions between the liquid and gaseous phases, zero-order production, and two first-order degradation reactions: one which is independent of other solutes, and one which provides the coupling between solutes involved in sequential first order decay reactions. In addition, physical non-equilibrium solute transport can be accounted for by assuming a two-region, dual-porosity type formulation which partitions the liquid phase into mobile and immobile regions.
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Typically, supercritical fluids are completely miscible with each other, so that a binary mixture forms a single gaseous phase if the critical point of the mixture is exceeded. However, exceptions are known in systems where one component is much more volatile than the other, which in some cases form two immiscible gas phases at high pressure and temperatures above the component critical points. This behavior has been found for example in the systems N2-NH3, NH3-CH4, SO2-N2 and n-butane-H2O. The critical point of a binary mixture can be estimated as the arithmetic mean of the critical temperatures and pressures of the two components, For greater accuracy, the critical point can be calculated using equations of state, such as the Peng-Robinson, or group-contribution methods.
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An electrode typically consists of carbon support, Pt particles, Nafion ionomer, and/or Teflon binder. The carbon support functions as an electrical conductor; the Pt particles are reaction sites; the ionomer provides paths for proton conduction, and the Teflon binder increases the hydrophobicity of the electrode to minimize potential flooding. In order to enable the electrochemical reactions at the electrodes, protons, electrons and the reactant gases (hydrogen or oxygen) must gain access to the surface of the catalyst in the electrodes, while the product water, which can be in either liquid or gaseous phase, or both phases, must be able to permeate from the catalyst to the gas outlet. These properties are typically realized by porous composites of polymer electrolyte binder (ionomer) and catalyst nanoparticles supported on carbon particles.
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Two adsorbate nitrogen molecules adsorbing onto a tungsten adsorbent from the precursor state around an island of previously adsorbed adsorbate (left) and via random adsorption (right) In other instances, molecular interactions between gas molecules previously adsorbed on a solid surface form significant interactions with gas molecules in the gaseous phases. Hence, adsorption of gas molecules to the surface is more likely to occur around gas molecules that are already present on the solid surface, rendering the Langmuir adsorption isotherm ineffective for the purposes of modelling. This effect was studied in a system where nitrogen was the adsorbate and tungsten was the adsorbent by Paul Kisliuk (1922–2008) in 1957. To compensate for the increased probability of adsorption occurring around molecules present on the substrate surface, Kisliuk developed the precursor state theory, whereby molecules would enter a precursor state at the interface between the solid adsorbent and adsorbate in the gaseous phase.
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This article summarises the main criteria of selecting working fluids for a thermodynamic cycle, such as heat engines including low grade heat recovery using Organic Rankine Cycle (ORC) for geothermal energy, waste heat, thermal solar energy or biomass and heat pumps and refrigeration cycles. The article addresses how working fluids affect technological applications, where the working fluid undergoes a phase transition and does not remain in its original (mainly gaseous) phase during all the processes of the thermodynamic cycle. Finding the optimal working fluid for a given purpose – which is essential to achieve higher energy efficiency in the energy conversion systems – has great impact on the technology, namely it does not just influence operational variables of the cycle but also alters the layout and modifies the design of the equipment. Selection criteria of working fluids generally include thermodynamic and physical properties besides economical and environmental factors, but most often all of these criteria are used together.
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The mixture of steam and water is led by the upper steam lines, one for each pressure channel, from the reactor top to the steam separators, pairs of thick horizontal drums located in side compartments above the reactor top; each has diameter, length, wall thickness of , and weighs . Steam, with steam quality of about 15%, is taken from the top of the separators by two steam collectors per separator, combined, and led to two turbogenerators in the turbine hall, then to condensers, reheated to , and pumped by the condensate pumps to deaerators, where remains of gaseous phase and corrosion-inducing gases are removed. The resulting feedwater is led to the steam separators by feedwater pumps and mixed with water from them at their outlets. From the bottom of the steam separators, the feedwater is led by 12 downpipes (from each separator) to the suction headers of the main circulation pumps, and back into the reactor.
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