Density alumina

The synthesis of the n=2 phase is similar to that described above for the n=l system. In general, stoichiometric portions of oxides and carbonates (or nitrates) are ground and reacted in a high density alumina crucible at temperatures between 800 and 820°C. The product is crushed and pressed into a pellet for further heat treatments at 840-870°C. The firing temperature must be raised incrementally to prevent melting of the sample. 

A Physical Electronics single-pass CMA and a Phi 4-grid LEED Optics unit were used in the studies of metal films on Ti02. Pd and Au films were evaporated from high-density alumina effusion sources. 

FIGURE 22.12 Socket in this artificial hip is made of high-density alumina. 

High Density Alumina (ceramic balls used 231 3.70 0.22 50.8 814... 

A typical rack employed for installation of specimens in pilot plants is shown in Fig. 6. Both corrosion coupons, 2 X 1 X 0.35 in. thick, and bend specimens intended to determine stress-corrosion cracking susceptibility, are included in the installation for aqueous corrosion testing. Specimens are separated by high density alumina spacers to eliminate electrochemical effects. During exposure, the racks are welded to existing components in the pilot plant equipment. 

Driskell, T.D., Spungenberg, H.D., Tennery, V. J. et al. 1973. Current status of high density alumina ceramic tooth roof structures. J. Dent Res. 52 123. 

Ceramics, inorganics, and glasses Bioactive glasses, bioactive glass/ceramics, high-density alumina, hydroxylapatite, single-crystal alumina, zirconia Carbons... 

Table IV summarizes the effect of various oxides on the resulting fiber properties [30-31]. The addition of increasing amounts of alumina, beryllia, yttria or nitride has already been discussed in Chapter 4.1.2. These modifiers tend to increase the modulus or stiffness of a glass fiber. In addition, alumina and baria tend to increase the density, alumina and strontia tend to increase the refractive index, and zinc oxide and zirconia tend to increase the alkali resistance of a fiber.

Table 3.2-12 Typical properties of high-density alumina [2.3]...

Fig. 5.30 Optimal ratio of DCCA for producing low-density alumina gel and TEM image (adapted from Can et al. (2005)).

De Porter, D.A., Watson, P.A., Pilliar, R.M. et al. 1986. A histological assessment of the initial healing response adjacent to porous-surfaced, titanium alloy dental implants in dogs. /. Dent. Res. 65 1064. Driskell, T.D., Spungenberg, H.D., Tennery, V.R et al. 1973. Current status of high density alumina ceramic tooth roof structures. J. Dent. Res. 52 123. 

The following preparation conditions have been used successfully in our laboratory. In all cases unless otherwise specified, 1-2 g samples were fired in high-density alumina boats. 

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