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  2. pH-sensitive polymers - Wikipedia

    en.wikipedia.org/wiki/PH-sensitive_polymers

    Materials may swell, collapse, or change depending on the pH of their environment. This behavior is exhibited due to the presence of certain functional groups in the polymer chain. pH-sensitive materials can be either acidic or basic, responding to either basic or acidic pH values. These polymers can be designed with many different ...

  3. pH - Wikipedia

    en.wikipedia.org/wiki/PH

    The measurement of pH can become difficult at extremely acidic or alkaline conditions, such as below pH 2.5 (ca. 0.003 mol/dm 3 acid) or above pH 10.5 (above ca. 0.0003 mol/dm 3 alkaline). This is due to the breakdown of the Nernst equation in such conditions when using a glass electrode.

  4. Buffer solution - Wikipedia

    en.wikipedia.org/wiki/Buffer_solution

    Buffer capacity falls to 33% of the maximum value at pH = pK a ± 1, to 10% at pH = pK a ± 1.5 and to 1% at pH = pK a ± 2. For this reason the most useful range is approximately pK a ± 1. When choosing a buffer for use at a specific pH, it should have a pK a value as close as possible to that pH. [2]

  5. Freshwater acidification - Wikipedia

    en.wikipedia.org/wiki/Freshwater_acidification

    Diagram depicting the sources and cycles of acid rain precipitation. Freshwater acidification occurs when acidic inputs enter a body of fresh water through the weathering of rocks, invasion of acidifying gas (e.g. carbon dioxide), or by the reduction of acid anions, like sulfate and nitrate within a lake, pond, or reservoir. [1]

  6. Cement board - Wikipedia

    en.wikipedia.org/wiki/Cement_board

    This 5 ⁄ 16 inch (7.9 mm) thick cement board is designed as an underlayment for tile floors. These are 3-by-5-foot (91 by 152 cm) sheets. These are 3-by-5-foot (91 by 152 cm) sheets. A cement board is a combination of cement and reinforcing fibers formed into sheets, of varying thickness that are typically used as a tile backing board. [ 1 ]

  7. Fascia (architecture) - Wikipedia

    en.wikipedia.org/wiki/Fascia_(architecture)

    Fascia (/ ˈ f eɪ ʃ ə /) is an architectural term for a vertical frieze or band under a roof edge, or which forms the outer surface of a cornice, visible to an observer. [ 1 ] Typically consisting of a wooden board, unplasticized PVC (uPVC), or non-corrosive sheet metal, many of the non-domestic fascias made of stone form an ornately carved ...

  8. Phenolphthalein - Wikipedia

    en.wikipedia.org/wiki/Phenolphthalein

    Phenolphthalein adopts different forms in aqueous solution depending on the pH of the solution. [4] [2] [5] [6] Inconsistency exists in the literature about hydrated forms of the compounds and the color of sulfuric acid. Wittke reported in 1983 that it exists in protonated form (H 3 In +) under strongly acidic conditions, providing an orange ...

  9. Soil pH - Wikipedia

    en.wikipedia.org/wiki/Soil_pH

    The prevailing view in the 1940s and 1950s was that P availability was maximized near neutrality (soil pH 6.5–7.5), and decreased at higher and lower pH. [29] [30] Interactions of phosphorus with pH in the moderately to slightly acidic range (pH 5.5–6.5) are, however, far more complex than is suggested by this view. Laboratory tests ...