In thermodynamics, the limit of local stability with respect to small fluctuations is clearly defined by the condition that the second derivative of Gibbs free energy is zero. The locus of these points (the inflection point within a G-x or G-c curve, Gibbs free energy as a function of composition) is known as the spinodal curve.[1][2][3] For compositions within this curve, infinitesimally small fluctuations in composition and density will lead to phase separation via spinodal decomposition. Outside of the curve, the solution will be at least metastable with respect to fluctuations.[3] In other words, outside the spinodal curve some careful process may obtain a single phase system.[3] Inside it, only processes far from thermodynamic equilibrium, such as physical vapor deposition, will enable one to prepare single phase compositions.[4] The local points of coexisting compositions, defined by the common tangent construction, are known as a binodal (coexistence) curve, which denotes the minimum-energy equilibrium state of the system. Increasing temperature results in a decreasing difference between mixing entropy and mixing enthalpy, and thus the coexisting compositions come closer. The binodal curve forms the basis for the miscibility gap in a phase diagram. The free energy of mixing changes with temperature and concentration, and the binodal and spinodal meet at the critical or consolute temperature and composition.[5]
https://en.wikipedia.org/wiki/Spinodal
The thermo-dielectric effect is the production of electric currents and charge separation during phase transition.
This interesting effect was discovered by Joaquim da Costa Ribeiro in 1944. The Brazilian physicist observed that solidification and melting of many dielectrics are accompanied by charge separation. A thermo-dielectric effect was demonstrated with carnauba wax, naphthalene and paraffin. Charge separation in ice was also expected. This effect was observed during water freezing period, electrical storm effects can be caused by this strange phenomenon. Effect was measured by many researches - Bernhard Gross, Armando Dias Tavares, Sergio Mascarenhas etc. César Lattes (co-discoverer of the pion) supposed that this was the only effect ever to be discovered entirely in Brasil.
https://en.wikipedia.org/wiki/Thermo-dielectric_effect
In physics, the terms order and disorder designate the presence or absence of some symmetry or correlation in a many-particle system.
In condensed matter physics, systems typically are ordered at low temperatures; upon heating, they undergo one or several phase transitions into less ordered states. Examples for such an order-disorder transition are:
- the melting of ice: solid-liquid transition, loss of crystalline order;
- the demagnetization of iron by heating above the Curie temperature: ferromagnetic-paramagnetic transition, loss of magnetic order.
The degree of freedom that is ordered or disordered can be translational (crystalline ordering), rotational (ferroelectric ordering), or a spin state (magnetic ordering).
The order can consist either in a full crystalline space group symmetry, or in a correlation. Depending on how the correlations decay with distance, one speaks of long range order or short range order.
If a disordered state is not in thermodynamic equilibrium, one speaks of quenched disorder. For instance, a glass is obtained by quenching (supercooling) a liquid. By extension, other quenched states are called spin glass, orientational glass. In some contexts, the opposite of quenched disorder is annealed disorder.
https://en.wikipedia.org/wiki/Order_and_disorder
Macroscopic quantum phenomena are processes showing quantum behavior at the macroscopic scale, rather than at the atomic scale where quantum effects are prevalent. The best-known examples of macroscopic quantum phenomena are superfluidity and superconductivity; other examples include the quantum Hall effect, giant magnetoresistance and topological order. Since 2000 there has been extensive experimental work on quantum gases, particularly Bose–Einstein condensates.
Between 1996 and 2016 six Nobel Prizes were given for work related to macroscopic quantum phenomena.[1] Macroscopic quantum phenomena can be observed in superfluid helium and in superconductors,[2] but also in dilute quantum gases, dressed photonssuch as polaritons and in laser light. Although these media are very different, they are all similar in that they show macroscopic quantum behavior, and in this respect they all can be referred to as quantum fluids.
Quantum phenomena are generally classified as macroscopic when the quantum states are occupied by a large number of particles (of the order of the Avogadro number) or the quantum states involved are macroscopic in size (up to kilometer-sized in superconducting wires).[3]
https://en.wikipedia.org/wiki/Macroscopic_quantum_phenomena
Plasma (from Ancient Greek πλάσμα 'moldable substance'[1]) is one of the four fundamental states of matter, first systematically studied by Irving Langmuir in the 1920s.[2][3] It consists of a gas of ions – atoms or molecules which have one or more orbital electrons stripped (or, rarely, an extra electron attached), and free electrons.
Excluding dark matter and the even more elusive dark energy, plasma is the most abundant form of ordinary matter in the universe.[4] Plasma is mostly associated with stars,[5] including our Sun,[6][7] and extending to the rarefied intracluster medium and possibly to the intergalactic regions.[8]
Plasma can be artificially generated by heating a neutral gas or subjecting it to a strong electromagnetic field. The presence of free charged particles makes plasma electrically conductive, with the dynamics of individual particles and macroscopic plasma motion governed by collective electromagnetic fields and very sensitive to externally applied fields.[9] The response of plasma to electromagnetic fields is used in many modern technological devices, such as plasma televisions or plasma etching.[10]
Depending on temperature and density, a certain amount of neutral particles may also be present, in which case plasma is called partially ionized. Neon signsand lightning are examples of partially ionized plasmas.[11] Unlike the phase transitions between the other three states of matter, the transition to plasma is not well defined and is a matter of interpretation and context:[12] Whether a given degree of ionization suffices to call the substance "plasma" depends on a specific phenomenon being considered. In other words, plasma is a matter which cannot be correctly described without the presence of charged particles taken into account.
https://en.wikipedia.org/wiki/Plasma_(physics)
A Rydberg polaron is an exotic state of matter, created at low temperatures, in which a very large atom contains other ordinary atoms in the space between the nucleus and the electrons.[1] For the formation of this atom, scientists had to combine two fields of atomic physics: Bose–Einstein condensates and Rydberg atoms. Rydberg atoms are formed by exciting a single atom into a high-energy state, in which the electron is very far from the nucleus. Bose–Einstein condensates are a state of matter that is produced at temperatures close to absolute zero.
Polarons are induced by using a laser to excite Rydberg atoms contained as impurities in a Bose–Einstein condensate. In those Rydberg atoms, the average distance between the electron and its nucleus can be as large as several hundred nanometres, which is more than a thousand times the radius of a hydrogen atom.[2] Under these circumstances, the distance between the nucleus and the electron of the excited Rydberg atoms is higher than the average distance of the atoms of the condensate. As a result, some atoms lie inside the orbit of the Rydberg atom's electron.
As the atoms don't have an electric charge, they only produce a minimal force on the electron. However, the electron is slightly scattered at the neutral atoms, without even leaving its orbit, and the weak bond that is generated between the Rydberg atom and the atoms inside of it, tying them together, is known as the Rydberg polaron. The new state of matter was predicted by theorists at Harvard University in 2016[3] and confirmed in 2018 by spectroscopy in an experiment using a strontium Bose–Einstein condensate.[4] Theoretically, up to 170 ordinary strontium atoms could fit closely inside the new orbital of the Rydberg atom, depending on the radius of the Rydberg atom and the density of the Bose–Einstein condensate.[2] The theoretical work for the experiment was performed by theorists at Vienna University of Technology and Harvard University,[5] while the actual experiment and observation took place at Rice University in Houston, Texas.
https://en.wikipedia.org/wiki/Rydberg_polaron
Photonic molecules are a theoretical natural form of matter which can also be made artificially in which photons bind together to form "molecules".[1][2][3] They were first predicted in 2007. Photonic molecules are formed when individual (massless) photons "interact with each other so strongly that they act as though they have mass".[4] In an alternative definition (which is not equivalent), photons confined to two or more coupled optical cavities also reproduce the physics of interacting atomic energy levels, and have been termed as photonic molecules.
Researchers drew analogies between the phenomenon and the fictional "lightsaber" from Star Wars.[4][5]
rubidium ruby may bettey
https://en.wikipedia.org/wiki/Photonic_molecule
A supercritical fluid (SCF) is any substance at a temperature and pressure above its critical point, where distinct liquid and gasphases do not exist, but below the pressure required to compress it into a solid.[1] It can effuse through porous solids like a gas, overcoming the mass transfer limitations that slow liquid transport through such materials. SCF are much superior to gases in their ability to dissolve materials like liquids or solids. In addition, close to the critical point, small changes in pressure or temperature result in large changes in density, allowing many properties of a supercritical fluid to be "fine-tuned".
Supercritical fluids occur in the atmospheres of the gas giants Jupiter and Saturn, the terrestrial planet Venus, and probably in those of the ice giants Uranus and Neptune. Supercritical water is found on Earth, such as the water issuing from black smokers, a type of underwater hydrothermal vent.[2] They are used as a substitute for organic solvents in a range of industrial and laboratory processes. Carbon dioxide and water are the most commonly used supercritical fluids; they are often used for decaffeination and power generation, respectively.
https://en.wikipedia.org/wiki/Supercritical_fluid
In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium.[1] It is that temperature and pressure at which the sublimation curve, fusion curve and the vaporisation curve meet. For example, the triple point of mercury occurs at a temperature of −38.83440 °C (−37.90192 °F) and a pressure of 0.165 mPa.
In addition to the triple point for solid, liquid, and gas phases, a triple point may involve more than one solid phase, for substances with multiple polymorphs. Helium-4 is a special case that presents a triple point involving two different fluid phases (lambda point).[1]
The triple point of water was used to define the kelvin, the base unit of thermodynamic temperature in the International System of Units (SI).[2] The value of the triple point of water was fixed by definition, rather than measured, but that changed with the 2019 redefinition of SI base units. The triple points of several substances are used to define points in the ITS-90 international temperature scale, ranging from the triple point of hydrogen (13.8033 K) to the triple point of water (273.16 K, 0.01 °C, or 32.018 °F).
The term "triple point" was coined in 1873 by James Thomson, brother of Lord Kelvin.[3]
https://en.wikipedia.org/wiki/Triple_point
Sublimation is the transition of a substance directly from the solid to the gas state,[1]without passing through the liquid state.[2] Sublimation is an endothermic process that occurs at temperatures and pressures below a substance's triple point in its phase diagram, which corresponds to the lowest pressure at which the substance can exist as a liquid. The reverse process of sublimation is deposition or desublimation, in which a substance passes directly from a gas to a solid phase.[3] Sublimation has also been used as a generic term to describe a solid-to-gas transition (sublimation) followed by a gas-to-solid transition (deposition).[4] While vaporization from liquid to gas occurs as evaporation from the surface if it occurs below the boiling point of the liquid, and as boiling with formation of bubbles in the interior of the liquid if it occurs at the boiling point, there is no such distinction for the solid-to-gas transition which always occurs as sublimation from the surface.
At normal pressures, most chemical compounds and elements possess three different states at different temperatures. In these cases, the transition from the solid to the gaseous state requires an intermediate liquid state. The pressure referred to is the partial pressure of the substance, not the total (e.g. atmospheric) pressure of the entire system. So, all solids that possess an appreciable vapour pressure at a certain temperature usually can sublime in air (e.g. water ice just below 0 °C). For some substances, such as carbon and arsenic, sublimation is much easier than evaporation from the melt, because the pressure of their triple point is very high, and it is difficult to obtain them as liquids.
The term sublimation refers to a physical change of state and is not used to describe the transformation of a solid to a gas in a chemical reaction. For example, the dissociation on heating of solid ammonium chloride into hydrogen chloride and ammonia is notsublimation but a chemical reaction. Similarly the combustion of candles, containing paraffin wax, to carbon dioxide and water vaporis not sublimation but a chemical reaction with oxygen.
Sublimation is caused by the absorption of heat which provides enough energy for some molecules to overcome the attractive forces of their neighbors and escape into the vapor phase. Since the process requires additional energy, it is an endothermicchange. The enthalpy of sublimation (also called heat of sublimation) can be calculated by adding the enthalpy of fusion and the enthalpy of vaporization.
https://en.wikipedia.org/wiki/Sublimation_(phase_transition)
In thermodynamics and chemical engineering, the vapor–liquid equilibrium (VLE) describes the distribution of a chemical speciesbetween the vapor phase and a liquid phase.
The concentration of a vapor in contact with its liquid, especially at equilibrium, is often expressed in terms of vapor pressure, which will be a partial pressure (a part of the total gas pressure) if any other gas(es) are present with the vapor. The equilibrium vapor pressure of a liquid is in general strongly dependent on temperature. At vapor–liquid equilibrium, a liquid with individual components in certain concentrations will have an equilibrium vapor in which the concentrations or partial pressures of the vapor components have certain values depending on all of the liquid component concentrations and the temperature. The converse is also true: if a vapor with components at certain concentrations or partial pressures is in vapor–liquid equilibrium with its liquid, then the component concentrations in the liquid will be determined dependent on the vapor concentrations and on the temperature. The equilibrium concentration of each component in the liquid phase is often different from its concentration (or vapor pressure) in the vapor phase, but there is a relationship. The VLE concentration data can be determined experimentally, approximated with the help of theories such as Raoult's law, Dalton's law, and Henry's law.
Such vapor–liquid equilibrium information is useful in designing columns for distillation, especially fractional distillation, which is a particular specialty of chemical engineers.[1][2][3] Distillation is a process used to separate or partially separate components in a mixture by boiling (vaporization) followed by condensation. Distillation takes advantage of differences in concentrations of components in the liquid and vapor phases.
In mixtures containing two or more components, the concentrations of each component are often expressed as mole fractions. The mole fraction of a given component of a mixture in a particular phase (either the vapor or the liquid phase) is the number of moles of that component in that phase divided by the total number of moles of all components in that phase.
Binary mixtures are those having two components. Three-component mixtures are called ternary mixtures. There can be VLE data for mixtures with even more components, but such data is often hard to show graphically. VLE data is a function of the total pressure, such as 1 atm or at the pressure the process is conducted at.
When a temperature is reached such that the sum of the equilibrium vapor pressures of the liquid components becomes equal to the total pressure of the system (it is otherwise smaller), then vapor bubbles generated from the liquid begin to displace the gas that was maintaining the overall pressure, and the mixture is said to boil. This temperature is called the boiling point of the liquid mixture at the given pressure. (It is assumed that the total pressure is held steady by adjusting the total volume of the system to accommodate the specific volume changes that accompany boiling.) The boiling point at an overall pressure of 1 atm is called the normal boiling point of the liquid mixture.
https://en.wikipedia.org/wiki/Vapor–liquid_equilibrium
Regelation is the phenomenon of ice melting under pressure and refreezing when the pressure is reduced. We can demonstrate regelation by looping a fine wire around a block of ice, with a heavy weight attached to it. The pressure exerted on the ice slowly melts it locally, permitting the wire to pass through the entire block. The wire's track will refill as soon as pressure is relieved, so the ice block will remain solid even after wire passes completely through. This experiment is possible for ice at −10 °C or cooler, and while essentially valid, the details of the process by which the wire passes through the ice are complex.[1] The phenomenon works best with high thermal conductivity materials such as copper, since latent heat of fusion from the top side needs to be transferred to the lower side to supply latent heat of melting. In short, the phenomenon in which ice converts to liquid due to applied pressure and then re-converts to ice once the pressure is removed is called regelation.
Regelation was discovered by Michael Faraday. It occurs only for substances such as ice, that have the property of expanding upon freezing, for the melting points of those substances decrease with the increasing external pressure. The melting point of ice falls by 0.0072 °C for each additional atm of pressure applied. For example, a pressure of 500 atmospheres is needed for ice to melt at −4 °C.[2]
https://en.wikipedia.org/wiki/Regelation
Plasma recombination is a process by which positive ions of a plasmacapture a free (energetic) electron and combine with electrons or negative ions to form new neutral atoms (gas). Recombination is an exothermic reaction, meaning heat releasing reaction. Except for plasma composed of pure hydrogen (or its isotopes), there may also be multiple charged ions. Therefore, a single electron capture results in decrease of the ion charge, but not necessarily in a neutral atom or molecule.
Recombination usually takes place in the whole volume of a plasma (volume recombination), although in some cases it is confined to some special region of it. Each kind of reaction is called a recombining mode and their individual rates are strongly affected by the properties of the plasma such as its energy (heat), density of each species, pressure and temperature of the surrounding environment.
https://en.wikipedia.org/wiki/Plasma_recombination
A colloid is a mixture in which one substance of microscopically dispersed insoluble particles are suspended throughout another substance. However, some definitions specify that the particles must be dispersed in a liquid,[1] and others extend the definition to include substances like aerosols and gels. The term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word suspension is distinguished from colloids by larger particle size). A colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension). The dispersed phase particles have a diameter of approximately 1 nanometreto 1 micrometre.[2][3]
Some colloids are translucent because of the Tyndall effect, which is the scattering of light by particles in the colloid. Other colloids may be opaque or have a slight color.
Colloidal suspensions are the subject of interface and colloid science. This field of study was introduced in 1845 by Italian chemist Francesco Selmi[4] and further investigated since 1861 by Scottish scientist Thomas Graham.[5]
https://en.wikipedia.org/wiki/Colloid
Glass is a non-crystalline, often transparent amorphous solid, that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda-lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term glass, in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material.
Although brittle, buried silicate glass will survive for very long periods if not disturbed, and many examples of glass fragments exist from early glass-making cultures. Archaeological evidence suggests glass-making dates back to at least 3,600 BC in Mesopotamia, Egypt, or Syria. The earliest known glass objects were beads, perhaps created accidentally during metalworking or the production of faience. Due to its ease of formability into any shape, glass has been traditionally used for vessels, such as bowls, vases, bottles, jars and drinking glasses. In its most solid forms, it has also been used for paperweights and marbles. Glass can be coloured by adding metal salts or painted and printed as enamelled glass. The refractive, reflective and transmission properties of glass make glass suitable for manufacturing optical lenses, prisms, and optoelectronics materials. Extruded glass fibres have application as optical fibres in communications networks, thermal insulating material when matted as glass wool so as to trap air, or in glass-fibrereinforced plastic (fibreglass).
https://en.wikipedia.org/wiki/Glass
In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules, usually related to the spins of electrons, align in a regular pattern with neighboring spins (on different sublattices) pointing in opposite directions. This is, like ferromagnetism and ferrimagnetism, a manifestation of ordered magnetism.
Generally, antiferromagnetic order may exist at sufficiently low temperatures, but vanishes at and above the N̩el temperature Рnamed after Louis N̩el, who had first identified this type of magnetic ordering.[1] Above the N̩el temperature, the material is typically paramagnetic.
https://en.wikipedia.org/wiki/Antiferromagnetism
https://en.wikipedia.org/wiki/Category:Dark_matter
https://en.wikipedia.org/wiki/Category:Superfluidity
https://en.wikipedia.org/wiki/Category:Compact_stars
https://en.wikipedia.org/wiki/State_of_matter
https://en.wikipedia.org/wiki/Primordial_black_hole
smashing pumpkins zero
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