Alpha prime

Chelidonic acid gantnia-pyi one-alpha, alpha-prime-dicarhoxylic add... 

Maruyama, Y N. Maruyama B. Mikami S. Utsumi. Crystal structure of soybean beta conglycinin alpha prime homotrimer. Deposited 2003a Top of Form http //pdbbeta.rcsb.org/pdb/explore. do structureId= 1UIK. 

Alpha prime dicalcium silicate is derived from alpha by phase transformation and crystallizes between 830°C and 1447°C n is 1.718 and is parallel tob riy is 1.717 and is parallel to a n is 1.732 and is parallel to c birefringence is 0.019 and (h-)2V is 30°. Alpha prime, according to Chromy (1970), has a birefringence of 0.013. Alpha prime C S is orthorhombic and can be stabilized by potassium, sodium, and phosphorus. Alpha primOj C S is monoclinic, stabilized by sodium and phosphorus. Alpha prime C S is orthorhombic. Some alpha prime C2S grains show striations of beta phase. Colors range from black, brown, yellow, green to colorless. Density is 3.31 Mg/m. According to Boikova (1980), n is 1.719, and is 1.732, with one, two, or three directions of lamellae. 

If the clinker is burned below the temperature of alpha prime inversion, and belite is cooled from the temperature region of alpha prime, belite has only the alpha prime to beta inversion texture. This texture is ob served as one set of parallel striations, which is polysynthetic twinning and parting on (100) and (010) after the crystal axes of the alpha prime. Rarely occurring are polysythetic twins on (110), (oil), and (011). 

Insley s (1936) morphological classification of belite into Type I, II, and III is particularly valuable because it is not confused with genetic or polymorphic restrictions. Even though Insley discussed polymorphic, compositional, and temperature variations, the morphological classification was apparently meant to be primarily observational with interpretation as a derivative. With progress in defining the relationships between polymorphic varieties of belite (alpha, alpha prime, and so on) and their common forms, we may eventually understand the rather complex genesis of the phases. For now, in the author s opinion, the nomenclature should remain descriptive. 

Microscopical appearances of belite polymorphs (alpha, alpha prime, beta, and gamma) have been described by Chromy and Garin (1980/81). These authors illustrated nonlamellar, alpha belite and stated that the transformation of alpha to alpha-prime dicalcium silicate is manifested by the growth of six sets of alpha-prime lamellae, the speed and completeness of the transformation being a function of the alkali concentration in the melt. 

Geis and Knofel (1986), in a laboratory-produced belite-rich cement (56% belite), state that alpha belite may be visible as light-gray reflecting lamellae with the alpha prime polymorph in clinkers with Na contents of approximately 1.5%. Asimilar occurrence, but less distinct, was observed in clinkers with KjO of... 

XRD of the heavy concentrate shows strong peaks for beta belite and weak peaks for alpha. The alpha percentage is estimated from the intensity of 32.95° to 33.00° 29, Cu-k j j radiation. Alpha prime gives a strong peak at 33.26° to 33.28° 20. 

Ono described the polymorphs of dicalcium silicate with transmitted-light microscopy and X-ray diffraction (XRD) in 1953, confirming the occurrence of alpha-prime, beta, and gamma forms. 

The effects of sodium, potassium, and magnesium oxides on the strength of mortar were investigated by Ono, Hidaka, and Shirasaka (1969) and optimum percentages were established. These authors concluded that mortar compressive strength was related to abundances of alpha and alpha-prime belite. 

At a temperature of approximately 1100°C to 1200°C alpha-prime belite forms as small crystals at about 1400°C the crystals change to alpha and exhibit considerable growth. Crystal size of belite, therefore, is primarily dependent on the time maintained above 1400°C—the burning time. 

Multidireotional lamellar struoture of belite Formed and coarsened during alpha to alpha prime transition during cooling (Hofmanner, 1973) clinker burned at greaterthan 1420°C (Ono, 1975)... 

Colorless Type II belite (parallel striations) Belite held at alpha-prime temperature in kiln coating (Ono, 1981) burning below 1420°C (Ono, 1975)... 

Polysynthetic twinning in belite Formed during very slow cooling as a result of alpha prime to beta transition (Hofmanner, 1973)... 

Ragged belite Alpha to alpha prime inversion in contact with melt and slow cooling (Ono, 1981)... 

Zoned belite with yellow or muddy colors in outer zone Differences in absorption of impurities produced by alpha prime to alpha transition (Ono, Kawamura, and Soda, 1968)... 

Jiang et al. (1992) investigated the alpha prime precipitation in aged duplex stainless steel. Samples (65% ferrite, 35% austenite) were aged at 450°C for 100, 1000, and 5000 h. The electrochemical behavior of the aged sample was examined in 0.1 - 0.5 M... 

Alpha prime transus Betatransus Melting (liquidus point) Density(a)... 

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