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Nitrogen is a liquid under −195.8 °C (77.3 K).. In physics, cryogenics is the production and behaviour of materials at very low temperatures.. The 13th International Institute of Refrigeration's (IIR) International Congress of Refrigeration (held in Washington, DC in 1971) endorsed a universal definition of "cryogenics" and "cryogenic" by accepting a threshold of 120 K (−153 °C) to ...
Cryochemistry is the study of chemical interactions at temperatures below −150 °C (−238 °F; 123 K). [1] It is derived from the Greek word cryos, meaning 'cold'.It overlaps with many other sciences, including chemistry, cryobiology, condensed matter physics, and even astrochemistry.
An example is magnetite (Fe 3 O 4), which contains Fe 2+ and Fe 3+ ions with different magnetic moments. A quantum spin liquid (QSL) is a disordered state in a system of interacting quantum spins which preserves its disorder to very low temperatures, unlike other disordered states. It is not a liquid in physical sense, but a solid whose ...
A definition of temperature can be based on the relationship: = The relationship suggests that a positive temperature corresponds to the condition where entropy, S, increases as thermal energy, q rev, is added to the system. This is the "normal" condition in the macroscopic world, and is always the case for the translational, vibrational ...
Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...
For example, the system triethylamine-water has an LCST of 19 °C, so that these two substances are miscible in all proportions below 19 °C but not at higher temperatures. [1] [2] The nicotine-water system has an LCST of 61 °C, and also a UCST of 210 °C at pressures high enough for liquid water to exist at that temperature. The components ...
Low-temperature helium is the only known exception to the general rule. [7] Helium-3 has a negative enthalpy of fusion at temperatures below 0.3 K. Helium-4 also has a very slightly negative enthalpy of fusion below 0.8 K. This means that, at appropriate constant pressures, heat must be added to these substances in order to freeze them. [8]
Cryogenics – cryogenics is the study of the production of very low temperature (below −150 °C, −238 °F or 123 K) and the behavior of materials at those temperatures. Econophysics – interdisciplinary research field, applying theories and methods originally developed by physicists to solve problems in economics