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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

A measurement of the completeness of an incomplete chemical reaction. It is defined as the negative logarithm(to the base 10) of the equilibrium constant, K, for the reaction in question. The pK is most frequently used to express the extent of dissociation or the strength of weak acids... In a solution of weak acid, if the concentration of undissociated acid is equal to the concentration of the anion of the acid, the pK will be equal to the pH.  1, record 1, English, - pK

Record number: 1, Textual support number: 1 OBS

ionisation behavior: term extracted from the “Glossaire de l’environnement” and reproduced with permission of the Organisation for Economic Co-operation and Development.  3, record 1, English, - pK

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 DEF

Expression signifiant -log K avec K = A x B sur AB expression de la loi d'action de masses pour la dissociation d'une molécule AB. Si le corps (acide sulfurique) subit deux dissociations successives, on trouvera des expressions notées pK₁ et pK₂.  1, record 1, French, - pK

Record number: 1, Textual support number: 1 OBS

On dit "pK", tout comme on dit "pH"; contrairement au pH, cependant, qui est le symbole du potentiel hydrogène, le symbole "pK" ne renvoit à aucun terme de référence.  3, record 1, French, - pK

Record number: 1, Textual support number: 2 OBS

comportement d'ionisation : terme extrait du «Glossaire de l’environnement» et reproduit avec l’autorisation de l’Organisation de coopération et de développement économiques.  4, record 1, French, - pK

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

A solution to which moderate amounts of either a strong acid or base may be added without causing any large change in the pH value of the solution. Such solutions usually contain (a) a weak acid and a salt of the weak acid, (b) a mixture of an acid salt with the normal salt, or (c) a mixture of two acid salts.  5, record 2, English, - buffer%20solution

Record number: 2, Textual support number: 1 CONT

For many situations, it is desirable to maintain the H+ and OH-concentration of a water solution at low and constant values. A useful device for this is a mixture of weak acid and its anion(or of a weak base and its cation). Such a mixture is called buffer.  6, record 2, English, - buffer%20solution

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 DEF

Mélange de solutions dont le pH ne s'altère pratiquement pas au cours d'une dilution. On prend généralement le mélange d'un acide fort (ou d'une base forte) avec un sel organique. Toute variation du pH y provoque une réaction tendant à restaurer l'équilibre primitif.  4, record 2, French, - tampon

Record number: 2, Textual support number: 1 OBS

pluriel : des solutions tampons (d'après le Dictionnaire de la chimie de Duval, 1978, p. 985).  5, record 2, French, - tampon

Record 2,  Textual support,  Spanish

Record number: 2, Textual support number: 1 DEF

Aquella cuyo pH se mantiene casi constante al añadir una cantidad moderada de un ácido o de una base.  2, record 2, Spanish, - soluci%C3%B3n%20amortiguadora

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

Substituted cellulose derivative that is used in bead form as weak ion exchanger. The most frequently used products are DEAE-cellulose(diethylaminoethyl) and CM-cellulose(carboxymethyl), which are weak base(anion) and weak acid(cation) exchangers, respectively. They are prepared from cellulose by substitution of some primary and secondary hydroxyl groups of the anhydroglucose units with diethylaminoethyl or carboxymethyl groups, respectively, joined through ether linkages.  1, record 3, English, - cellulose%20ion%20exchanger

Record number: 3, Textual support number: 1 CONT

Ion exchange celluloses can be used in both column and batch processes, although for large-scale work difficulty has been encountered in using large columns of these materials. The cellulose is easily compressed, and this leads rapidly to a reduction in flow rate. Thus the main application of ion exchange cellulose in large-scale enzyme purification has been for batch adsorption and batch elution.  3, record 3, English, - cellulose%20ion%20exchanger

Record number: 3, Textual support number: 1 OBS

These exchangers have an open structure, which is readily penetrated by large molecules, and a large surface area giving them a high capacity for absorption of protein. The binding is usually freely reversible. DEAE-cellulose is used for chromatography of acidic and slightly basic proteins at pH values above their isoelectric point. The most useful range is pH 6-8. CM-cellulose is used for separation of neutral and basic proteins, which bind at around pH 4.5. Desorption of proteins from the ion exchangers is accomplished by changing the pH or increasing the ionic strength of the eluant.  1, record 3, English, - cellulose%20ion%20exchanger

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 CONT

L'industrie biologique utilise aujourd'hui les techniques chromatographiques pour la production de protéines purifiées. L'insuline par exemple, est isolée à partir de pancréas de bovins ou de porcs par des procédés combinant l'échange d'ions et le tamisage moléculaire. Ces mêmes techniques ou la chromatographie d'affinité sont également utilisées pour la purification de macromolécules nécessaires à certains vaccins : le virus poliomyélitique, la toxine du choléra et la tixine du tétanos. Ce développement (...) commence vraiment en 1956 avec la création des celluloses échangeuses d'ions par Peterson et Sober, utilisables dans la séparation des protéines.  1, record 3, French, - cellulose%20%C3%A9changeuse%20d%27ions

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 OBS

The anion exchanger through which the decationized water now passes may consist of... a weak base resin... which retains strong acids but not weak acids, such as carbonic acid and silicic acid; carbonic acid can be eliminated subsequently by atmospheric degassing...  1, record 4, English, - atmospheric%20degassing

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 OBS

L'échangeur d'anions [...] peut être constitué [...] par une résine de faible basicité qui retient les acides forts mais non les acides faibles [...] l'acide carbonique peut ensuite être éliminé par dégazage atmosphérique [...]  1, record 4, French, - d%C3%A9gazage%20atmosph%C3%A9rique

Record 4,  Textual support,  Spanish

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

The anion exchanger through which the decationized water now passes may consist of :... a weak base resin... which retains strong acids but not weak acids, such as carbonic acid and silicic acid; carbonic acid can be eliminated subsequently by atmospheric degassing...  1, record 5, English, - weak%20base%20resin

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 CONT

L'échangeur d'anions [...] peut être constitué [...] par une résine de faible basicité qui retient les acides forts mais non les acides faibles [...] l'acide carbonique peut ensuite être éliminé par dégazage atmosphérique [...]  1, record 5, French, - r%C3%A9sine%20de%20faible%20basicit%C3%A9

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 CONT

The consecutive weak and strong acid cation exchangers, as well as the successive weak and strong base anion exchangers, can be used in a single unit with two superimposed layers, known as "stratified beds" which are kept separate by the choice of resins of different densities.  1, record 6, English, - superimposed%20layer

Record 6,  Textual support,  French

Record number: 6, Textual support number: 1 CONT

Les échangeurs successifs de cations faiblement et fortement acides, de même que les échangeurs successifs d'anions faiblement et fortement basiques, peuvent être utilisés dans un seul appareil en deux couches superposées obtenues en utilisant des résines de densités différentes.  1, record 6, French, - couche%20superpos%C3%A9e

Record 6,  Textual support,  Spanish