White Portland cement

MRI of concrete materials is challenging due to the short signal lifetimes and the low experimental sensitivity of magnetic resonance in general. The bulk Ti and T2 and T2 of1]- from water in white Portland cement systems have been shown to be... 

Concrete made with a water-to-cement ratio of w/c = 0.6, white Portland cement and quartz aggregates was cast in 100-mm long and 48-mm diameter cylinders. 

A cement paste phantom was prepared from white Portland cement. A thin sheet of copper was placed in the top of the specimen at the time of casting to produce a synthetic crack 300-pm wide, 8-mm long and 3-4-mm deep. The sheet was removed the following day. The specimens were 10 x 10 x 10 mm. At the time of demolding, the specimen was slightly damaged and two cracks formed on the corners of the specimen. The thicknesses of these cracks was estimated to be 100 pm and 60 pm. Prior to the MRI measurement the samples were stored in water to ensure saturation. 

White pigments, for inks, 14 317 White Portland cements, 5 500t White river crawfish... 

Other Types of Portland Cements. White Portland cement is standard Type I or III Pordand cement with raw materials selected and controlled to have negligible amounts of iron and manganese oxides, which impart the gray color. The white Pordand cement is used in decorative and architectural applications like precast curtain walls, terrazzo surfaces, stucco, tile grout, and decorative concrete. 

To make cement-coated plates, one part Ti02 powder was mixed with three parts white Portland cement then mixed with the appropriate amount of water. The mixture was set on a slate plate. The typical Ti02 coating density was 165 g nr2. 

J.J. Thomas, J.J. Chen, H.M. Jennings D.A. Neumann (2003). Chem. Mater., 15, 3813-3817. Ca-OH Bonding in the C-S-H gel phase of tricalcium silicate and white Portland cement pastes measured by inelastic neutron scattering. 

Up to 10% of pigment by weight of cement may be added depending on the depth of colour required. Used with white Portland cement it is possible to produce pastel shades. 

White Portland cement has the main components hsted in Table 9.6. 

Table 9.6 Main Components of white Portland cement [61]...

Q. Li, N.J. Coleman, Early hydration chemistry of white Portland cement in the presence of bismuth oxide, Adv. Appl. Ceram. 112 (2013) 207-212. 

Photograph 10-28 Powder mount of acetic-acid insoluble residue, >45pm, showing abundant large quartz grains (multicolored) and rhombohedral dolomite crystals (arrows). Raw feed for white Portland cement. (S A6896)... 

As the typical gray color of ordinary Portland cement is due to the presence of the ferrite phase, low-iron clinkers may be used in the production of white Portland cement, if the Fe203 content is kept suffieiently low, and if appropriate measures are taken to eliminate or reduce the effect of residrral iron on the color of the resultant clinker. 

Muntean (1992) produced a white Portland cement with a high belite content by burning a raw meal consisting of limestone and bentonite or tuff at 1300-1350 °C. The whiteness of the resultant cement could be significantly improved by adding 5% of... 

Gaidzhurov, P.P., and Zubar, T.G. (1994) Concentration dependence of glass-phase parameters on whiteness of white Portland cement elinker (in Russian). Izvestiya Vysshikh Uchebnykh Zavedenii, Khimiya I Khimicheskaya Tekhnologiya 37,73-75 [ref. CA 121/261973]. 

Singh, N.B., and Singh, A.K. (1989) Effect of Melment on hydration of white Portland cement. Cement and Concrete Research 19,547-553. 

The most commonly produced cement is Portland cement to British Standard BS 12, which represents 90% of the market, which includes products such as rapid hardening and coarse ground cements, and white Portland cement (WPC). Other cements covered by other British Standards include sulfate resisting Portland cement (SRPC), Portland blast furnace cement, high slag blast furnace cement, and Portland PFA cement. 

White Portland cement A Portland cement, produced from raw materials low in iron, which hydrates to a white paste used to yield a concrete of considerable whiteness. 

Figure 11.14 Coloured corona expanding around LWA aggregate saturated with weak ink solution and cast in the white Portland cement paste of water cement ratio 0.3 Lura et al. (2006).

Dunster, A. M., Kendrick, D. P., and Personage, J. R., The Mechanism of Hardening and Hydration of White Portland Cement Admixed with Salicyhc Aldehyde, Cement Concr. Res., 24 542-550 (1994)... 

Figure 4.1 XRD scans (IO°-45° 20 range) of typical industrially produced cements white Portland cement (WPC), plain portland cement (PC), calcium aluminate cement (CAC) and calcium sulfoaluminate cement (CSA). The diffraction peaks of the main phases are indicated alite (CjS M3), belite (P-CjS), aluminate (CjA), ferrite (C4AF), calcium aluminate (CA), ye elimite (Yee), anhydrite (Anh), gypsum (Gyp), gehlenite (Geh), mayenite (May) and magnetite (Mag).

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