Alkali glass

Another widely studied phenomenon in alkah borate glasses is the mixed alkah effect, the nonlinear change in glass properties when a second kind of alkah oxide is added into the single-alkali glass. Models have been suggested to explain the mixed alkah effect (144), but a universally accepted model has not been developed as of this writing. 

Day, D.E. (1976). Mixed alkali glasses - their properties and uses. Journal of... 

Fig. 4.1 Arrhenius plots for ionic conductivity, (a) General behaviour for ionically conducting glasses. At room temperature, the most conductive (Li or Ag ) have the lowest activation energy. For the less conductive glasses (Cs or mixed alkali glasses) the activation energy is around 1 eV. (b) Experimental data for Li conducting glasses (Souquet and Kone, 1986).

Robinson C. C. (1974). Multiple sites for Er in alkali glasses. Jour. Non-Cryst. Solids, 15 1-10. 

Assume that if Figure 15.8 is extrapolated to 200 °C, the viscosity of the lead-alkali glass is 1018 Pa s. Using this viscosity, calculate the strain that would occur in five centuries under a stress of 0.007 Pa. Assume that the stress is caused by the weight of a panel of glass 1/3 m high. Note that... 

Ureilites contain a variety of trace accessory phases. Metallic spherules composed of cohenite, metal, and sulfide are included in olivine and pigeonite of a few ureilites, and metal, phosphide, and sulfide are present as interstitial phases in most. The interstitial regions also commonly contain fine-grained silicates, including low-calcium pyroxene, augite and Si-Al-alkali glass. 

Cation Distributions in Single Alkali Glasses Studied by Wa Spin Echo... 

Table 6.2 Summary of properties for mixed alkali glasses (After Day, 1976).

FWHM and A is the value of A v corresponding to the rigid lattice - low temperature) and found that the Li jump frequency does decrease much the same way as in mixed alkali glasses. 

Ngai and Jain (1986) investigated the a.c. electrical conductivity (discussed in chapter 7) of mixed isotope and mixed alkali glasses and... 

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