recambiaron
Pretérito para el sujetoellos/ellas/ustedesdel verborecambiar.

recambiar

Pero, el cambio de pH de las soluciones fue marginal cuando los ácidos no se recambiaron y las soluciones amortiguadoras no se diluyeron.
However, the change of pH of the solutions was marginal when the acids were not replaced and when the buffer solutions were not diluted.
Los esclerocios fueron colocados dos semanas en soluciones de ácidos acético (0.4, 0.8 y 1.7 mmol L-1) y sulfúrico (0.25, 0.5 y 1 mmol L-1), éstas soluciones no se recambiaron o se hicieron una, dos o tres veces.
The sclerotia were placed in acetic (0.4, 0.8 and 1.7 mmol L-1) and sulfuric acid solutions (0.25, 0.5 and 1 mmol L-1) for two weeks; these solutions were not replaced or were remade one, two or three times.
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