| 释义 |
portlandite Min.|ˈpɔətləndaɪt|
[f. Portland1 (see quot. 1933) + -ite1.]
A form of calcium hydroxide that occurs naturally as minute hexagonal colourless plates and is a common product of the hydration of Portland cement.
1933C. E. Tilley in Mineral. Mag. XXIII. 420 The occurrence of Ca(OH)2 as a well-defined species is the contact-zone of Scawt Hill [Co. Antrim] merits a new mineral name, and in view of its occurrence as a common product of hydration of Portland cement, and furthermore as crystals from this source have provided the first reliable physical and optical data on crystalline Ca(OH)2, it is fitting that the mineral name should bear record of these facts. The name Portlandite is accordingly proposed. 1968I. Kostov Mineral. 221 Periclase group... The calcium members are rare minerals: portlandite occurs in metasomatic deposits in limestones. 1977Sci. Amer. Aug. 84 In a hardened cement this gel..occupies about 70 percent by volume of the hydrated material... The major part of the other crystalline products consists of calcium hydroxide (portlandite). |