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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

Measure of a system’s ability to do work. It is defined by F = U - TS, where U is the internal energy. For a reversible isothermal process, [delta]F represents the useful work available.  2, record 1, English, - free%20energy

Record number: 1, Textual support number: 1 CONT

Reactions that release a large quantity of free energy are those that have a very large negative [delta]G and create much disorder. Such reactions will have a strong tendency to occur, although the rate at which they do so will depend on other factors, such as the availability of specific enzymes. Conversely, reactions with a positive value of [delta]G create net order in the universe and cannot occur spontaneously. Such energetically unfavorable reactions will happen only if they are coupled to a second reaction with a negative [delta]G so large that the [delta]G of the entire process is negative.  3, record 1, English, - free%20energy

Record number: 1, Textual support number: 1 OBS

The change in free energy, G, is a measure of the tendency of a reaction at constant pressure to proceed spontaneously.  4, record 1, English, - free%20energy

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 DEF

Fonction d'état d'un système à l'équilibre, notée souvent F et égale à U - TS, où U est l'énergie interne, T la température et S l'entropie du système. (Lors d'une transformation isotherme, la variation de cette énergie est égale au travail reçu par le système.)  2, record 1, French, - %C3%A9nergie%20libre

Record number: 1, Textual support number: 1 CONT

Notons que l'enzyme ne détermine pas le sens de la réaction; la proportion de molécules X et Y, à l'équilibre, dépend de facteurs thermodynamiques : la réaction favorisée est celle qui minimise ce que l'on appelle l'énergie libre. (L'énergie libre d'un système est égale à son énergie totale diminuée de son entropie, c'est-à-dire d'une quantité qui caractérise le désordre du système.)  3, record 1, French, - %C3%A9nergie%20libre

Record number: 1, Textual support number: 1 OBS

Pour caractériser une réaction, on parle aussi de variation d'enthalphie libre [delta]G = [delta]U + P[delta]V - T[delta]S où P est la pression et [delta]V, la variation de volume. En biochimie, on peut admettre que [delta]V = 0, car les variations de volume pour les réactions ayant lieu en solution sont négligeables. Ainsi, [delta]G = [delta]U - T[delta]S = [delta]F. Par conséquent [delta]F se confond avec [delta]G. Ceci est vrai surtout si les réactions font intervenir des liquides et des solides en solution (et aucun gaz) aux températures physiologiques qui sont basses.  4, record 1, French, - %C3%A9nergie%20libre

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

In meteorology, the condition existing in a given portion of the atmosphere (or other space) when the relative humidity is greater than 100 per cent, that is, when it contains more water vapor than is needed to produce saturation with respect to a plane surface of pure water or pure ice.  2, record 2, English, - supersaturation

Record number: 2, Textual support number: 1 OBS

Such supersaturation does develop because frequently there is no "plane surface of pure water(or ice) "available. In the absence of water surfaces and in the absence of condensation nuclei or any wettable surfaces, phase change from vapor to liquid cannot occur due to the free energy barrier imposed by the surface free energy of the embryonic droplets which would then have to form by spontaneous nucleation... Cloud condensation occurs in our atmosphere at relative humidities near 100 per cent only because nature provides an abundance of condensation nuclei.  2, record 2, English, - supersaturation

Record number: 2, Textual support number: 2 OBS

A most air sample is said to be supersaturated with respect to water or to ice.  3, record 2, English, - supersaturation

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Formation des nuages. - La condensation se produit théoriquement quand l'air qui se refroidit atteint le point de condensation mais si l'air est très pur, il peut contenir une quantité de vapeur d'eau supérieure à la saturation sans que la phase liquide apparaisse. On parle alors de sursaturation.  2, record 2, French, - sursaturation

Record number: 2, Textual support number: 1 OBS

Il faut préciser s'il s'agit d'une sursaturation par rapport à la glace ou par rapport à l'eau.  3, record 2, French, - sursaturation

Record number: 2, Textual support number: 2 OBS

Le terme «sursaturation» a aussi un autre sens en chimie physique.  3, record 2, French, - sursaturation

Record 2,  Textual support,  Spanish

Record number: 2, Textual support number: 1 DEF

Estado del aire que contiene más vapor del que corresponde, como máximo, a su temperatura y presión.  1, record 2, Spanish, - sobresaturaci%C3%B3n

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

Linking of an exogonic reaction and an endogonic reaction in such a way that there is only a small net change in free energy, resulting in an overall reversible reaction. In living organisms, anabolic reactions are coupled with catabolic reactions resulting in the build up of complex molecules, but with an overall loss of energy as metabolic heat.  2, record 3, English, - coupled%20reaction

Record number: 3, Textual support number: 1 CONT

Coupling is brought about when an enzyme causes a substrate that is to be consumed ... to react with one of the cell’s small-molecule energy donors (say, ATP) to give rise to an energized activated substrate molecule. The subsequent decomposition of this activated substrate in the synthetic reaction will release significant energy, which will result in the synthetic reaction .... The need for cells to carry on simultaneously many different coupled reactions requires cells to devote a significant part of their total metabolic activity to the constant replenishment of their ATP supply. In animal cells and in most bacteria, the formation of ATP is coupled with the breakdown of food molecules that are even more rich in energy. In cells that carry out photosynthesis, the energy of sunlight is used directly to make ATP.  3, record 3, English, - coupled%20reaction

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

Les cellules vivantes doivent effectuer un certain nombre de réactions endergoniques; ce sont non seulement des réactions anaboliques [...], mais encore certaines réactions de transports, de transmissions, des travaux mécaniques, fonctionnement du système nerveux, réactions cataboliques, en particulier lorsque les substrats doivent être activés avant de pouvoir être dégradés. [...] L'énergie nécessaire est fournie par les réactions exergoniques grâce au couplage énergétique. Ce couplage énergétique est une des grandes caractéristiques des êtres vivants. D'une part, il implique que la réaction exergonique qui fournit l'énergie ait un [delta]G' négatif plus élevé en valeur absolue que le [delta]G' positif de la réaction endergonique qui lui est couplée. D'autre part, les deux réactions couplées doivent avoir un intermédiaire commun.  2, record 3, French, - r%C3%A9action%20coupl%C3%A9e

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

Both stress and temperature changes alter the dimensions of an object having a finite stiffness and a nonzero thermal expansion coefficient. Applying a stress then produces a temperature change; this can result in a heat flow which then changes the stress : these are thermoelastic effects, and result in losses of free energy.  1, record 4, English, - thermoelastic

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 OBS

Qui devient extensible après une baisse de température.  1, record 4, French, - thermo%C3%A9lastique

Record 4,  Textual support,  Spanish