释义 |
Definition of pH in English: pHnoun piːˈeɪtʃ Chemistry A figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline. The pH is equal to −log₁₀c, where c is the hydrogen ion concentration in moles per litre. Example sentencesExamples - At relatively alkaline pHs (found under stress), even very low ABA concentrations found in the xylem of well-watered plants will limit leaf growth rate.
- At specific concentrations and pHs, these dyes identified the distribution of macromolecules such as proteins, lipids, nucleic acids, or polysaccharides in the developing egg chamber and other tissues.
- Non-enzymatic reduction of DHA by reduced glutathione in phosphate buffers of different pHs was also measured in a separate cuvette at the same time.
- Additionally, another 5 to 16% is excreted daily into the gastric juices, since TCAs have a pK a of 9.5 and are highly ionized at acid pHs, thereby favoring concentration in the acid stomach.
- Prof. Lilley who had no experience in measuring the pHs of surfactant solutions having a high solids content was surprised to see a 0.3 difference in measurements.
Origin Early 20th century: from p representing German Potenz 'power' + H2, the symbol for hydrogen. |