Low-energy gases

Table 1 gives the typical chemical compositions of some of the main fuels by individual molecules, by families of molecules or by analysis of the elements. These include natural gases (NG), liquefied petroleum gases (LPG), unleaded petrols, turbojet fuels, diesel fuels and diesel fuel oils, heavy fuels, low-energy gases. 

It should be noted that, apart from the low-energy gases, the main constituents of fuels are hydrocarbons. 

Gaseous fuels include natural gas (Table la), the low-energy gases of the blast furnaces and coke ovens (Table Ig), as well as various heating gases, which are produced by steamcrackers and later recycled for heating. 

Low-energy gases can also be used in diesel stationary engines to produce electricity. 

PDMS based siloxane polymers wet and spread easily on most surfaces as their surface tensions are less than the critical surface tensions of most substrates. This thermodynamically driven property ensures that surface irregularities and pores are filled with adhesive, giving an interfacial phase that is continuous and without voids. The gas permeability of the silicone will allow any gases trapped at the interface to be displaced. Thus, maximum van der Waals and London dispersion intermolecular interactions are obtained at the silicone-substrate interface. It must be noted that suitable liquids reaching the adhesive-substrate interface would immediately interfere with these intermolecular interactions and displace the adhesive from the surface. For example, a study that involved curing a one-part alkoxy terminated silicone adhesive against a wafer of alumina, has shown that water will theoretically displace the cured silicone from the surface of the wafer if physisorption was the sole interaction between the surfaces [38]. Moreover, all these low energy bonds would be thermally sensitive and reversible. 

The apparatuses used for the studies of both ammonia synthesis emd hydrodesulfurization were almost identical, consisting of a UHV chamber pumped by both ion and oil diffusion pumps to base pressures of 1 x10 " Torr. Each chamber was equipped with Low Energy Electron Diffraction optics used to determine the orientation of the surfaces and to ascertain that the surfaces were indeed well-ordered. The LEED optics doubled as retarding field analyzers used for Auger Electron Spectroscopy. In addition, each chamber was equipped with a UTI 100C quadrupole mass spectrometer used for analysis of background gases and for Thermal Desorption Spectroscopy studies. 

Gilardini, A. (1972), Low Energy Collisions in Gases, ch. 1, Wiley, New York. 

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