Properties and Characterisation

The acidity of sites in the walls for surfactant templated aluminosilicates, or silicates doped with other transition metals prepared via surfactant templating can be characterised using a range of techniques including temperature-programmed desorption (TPD) of ammonia, ° solid-state NMR with probe molecules such as trimethylphosphine which bind to acid sites or Fourier transform infrared and diffuse reflectance UV-Vis with ammonia or CO probes.These techniques show that 

The interpretation of gas adsorption isotherms, typically nitrogen adsorption, for these materials is problematic due to the pore sizes, since for 

By combining measurements of the repeat spacing from XRD measurements and pore diameters from one of the above techniques, or from modelling of the intensities of XRD peaks, the wall thickness of these materials can be calculated. The wall thicknesses of materials templated using neutral surfactants with EO headgroups, in particular the triblock copolymers such as the Pluronic series are much greater than those templated using small molecule cationic or anionic surfactants. Early measurements of the wall thicknesses of MCM-41 and MCM-48 found a width of about 8 A, equivalent to about two layers of tetrahedral SiOi units.  

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Figure 1 Polymers in materials science Interrelationships between synthesis, processing, microstructure, properties and characterisation.

Physical Properties and Characterisation of Small Gold Particles... 

FIGURE 6.9 Illustration of chain structure of poly(3-alkylthiophene) showing effect of head-head (HH) coupling in a mainly head-tail (HT) coupled chain. (From Jeffries-El, M. and McCullough, R.D., in Handbook of Conducting Polymers. Conjugated Polymers. Theory, Synthesis, Properties and Characterisation, 3rd edition, Skotheim, T.A. and Reynolds, J.R. (Eds.), CRC Press, Boca Raton, 2007, 9-1. With permission.)... 

Pouch, J. J., and Altovitz, A. (eds.). Properties and Characterisation of Amorphous Carbon Films, Materials Science Forum, 52 and 53, Trans Tech Publications, Zurich,... 

The above phenomena and descriptions indicate the importance of dust properties and characterisation. Current trends and experiences indicate the following major influential properties ... 

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