摘要:

Solid electrolytes with structural disorder generally exhibit characteristic deviations from standard—theory spectra. The effect is known as “universal” dynamic response. In the jump—relaxation model, it is traced back to the Coulomb interaction among the mobile ions. The phenomena are consistently explained in terms of the non—random hopping resulting from the repulsive interaction.

ISSN:1042-0150    

DOI:10.1080/10420159108220765

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

One of the main problems in optical materials in the growth of single crystals and the characterization of their defects in view of performances and applications.

ISSN:1042-0150    

DOI:10.1080/10420159108220766

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

We have used Time Domain Reflectometry, which appears to be a powerful and efficient technique, to study the ionic conductivity and permittivity of superionic conductors. The differences in the defect structure occurring for doping of SrF2with different rare earth ions play an important role in the dielectric properties of these materials.

ISSN:1042-0150    

DOI:10.1080/10420159108220767

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The surface potential on pure and doped sodium chloride single crystals fits conventional defect theory, but the potential on grain boundaries in bicrystals is difficult to explain. The electrical width of the grain boundary is also an uncertain quantity that needs further investigation.

ISSN:1042-0150    

DOI:10.1080/10420159108220768

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Preliminary results of a combined EXAFS and computer simulation study of rare-earth doped β″-alumina are presented.

ISSN:1042-0150    

DOI:10.1080/10420159108220769

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The results of Molecular Dynamics simulations of borate glass (B2O3) using three-particle interactions are presented. These calculations yield a glass consisting of randomly connected BO3triangles. Infrared and Raman spectra have been calculated and compared with experimental spectra. The calculated infrared spectra show two main bands, one at 650 cm−1and one at 1250 cm−1, in agreement with experiment. The Raman spectra reproduce the experimental peak at 805 cm−1but the peak width is a factor of ten too large. Apparently, the simulated glasses have less short range order than the laboratory glasses.

ISSN:1042-0150    

DOI:10.1080/10420159108220770

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

When the computer-simulated potassium-doped polyaceteylene lattice is relaxed free of restrictions, the chains of the host polymer deviate from strict planarity. On introducing a K+vacancy in two lattices containing different amounts of dopant, defective lattice calculations show that the structure with the lower doping level is favoured, but that samples probably also contain regions with the higher doping level. The mobility of the K+ions is expected to be very high when vacancies are present in the dopant sublattice.

ISSN:1042-0150    

DOI:10.1080/10420159108220771

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

In order to provide missing data for storage of actinide containing solidified radioactive waste in deep underground dry geological formations such as salt domes, the tracer diffusion of U-233 was measured in single crystals of NaCl and in actual salt of a repository site (Asse mine in FR Germany). Experiments on interdiffusion between actinide-doped waste glasses and salt were also performed. The mean actinide penetration at the expected maximum temperature of the interface waste matrix/salt in 106years is extrapolated to be ≤ 1 μm for volume diffusion and ≤ a few μm for grain boundary diffusion.

ISSN:1042-0150    

DOI:10.1080/10420159108220772

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Defects of nitrogen impurity in silicon dioxide are investigated by the quantum chemical method with cluster approach. The model for the observed nitrogen center in silica glass was proposed.

ISSN:1042-0150    

DOI:10.1080/10420159108220773

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

We have measured all three tunneling parameters for the KCl:Li system as a function of hydrostatic pressure; all increase with pressure. Our measurements show that the off-center tunneling model works exceedingly well for this system. Surprisingly, the pressure dependence of the electric dipole moment shows a sharp break near 900 bar. In some samples, additional lines indicate other Li centers are present, possibly Li pairs.

ISSN:1042-0150    

DOI:10.1080/10420159108220774

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor