Materials impregnation

For the lubricated machines, vanes are made of a laminated material impregnated with phenolic resin. For a non-lubricated design, carbon is used. The vane number influences the differential pressure between adjacent vane cells. This influence becomes less as the number of vanes increases. 

The combination of different analytical techniques offers the possibility for a complete characterization of building materials impregnated with liquid alkyl-alkoxysilanes RSi(OC2H5)3. The results derived from IR, NMR and SIMS spectra can be summarized in the schematic layer structure shown in Figure 5. 

Impregnation modification of wood is darned as any method that results in the fdling of the wood substance with an inert material (impregnant) in order to bring about a desired petformance change. 

Supported Au catalysts have been extensively studied because of their unique activities for the low temperature oxidation of CO and epoxidation of propylene (1-5). The activity and selectivity of Au catalysts have been found to be very sensitive to the methods of catalyst preparation (i.e., choice of precursors and support materials, impregnation versus precipitation, calcination temperature, and reduction conditions) as well as reaction conditions (temperature, reactant concentration, pressure). (6-8) High CO oxidation activity was observed on Au crystallites with 2-4 nm in diameter supported on oxides prepared from precipitation-deposition. (9) A number of studies have revealed that Au° and Au" play an important role in the low temperature CO oxidation. (3,10) While Au° is essential for the catalyst activity, the Au° alone is not active for the reaction. The mechanism of CO oxidation on supported Au continues to be a subject of extensive interest to the catalysis community. 

Liquid Air and Liquid Oxygen Explosives originally consisted of porous combustible materials impregnated with liquid air. Soon after liq oxygen became commercially available it began to replace liq air in these explosives. Consequently this article is devoted almost entirely to Liquid Oxygen Explosives commonly called LOX. It should be noted that LOX are not to be confused with Fuel-Air Explosives (See FAE in Vol 6, p F3). 

Table I. Percolation and Resistance Tests on Backing Materials Impregnated with...

TRU-Resin type materials impregnated with both extractant and scintillating fluors column sensors ... 

The most popular thermionic detector (TID) is the nitrogen-phosphorus detector (NPD). The NPD is specific for compounds containing nitrogen or phosphorus. The detector uses a thermionic emission source in the form of a bead or cylinder composed of a ceramic material impregnated with an alkyl-metal. The sample impinges on the electrically heated and now molten potassium and rubidium metal salts of the active element. Samples which contain N or P are ionized and the resulting current measured. In this mode, the detector is usually operated at 600-800°C with hydrogen flows about 10 times less than those used for flame-ionization detection (FID). 

Mg(Ci04)2 (Anhydrone) Mg(C104)2 6H2O Caution This is an oxidizing agent. Cloth and other organic materials impregnated with perchlorate can be flammable. 

Figure 6.16 Building material impregnated with water-repellent silicone. Reproduced with permission from Rhone-Poulenc Silicones, Lyon, France...

Furthermore, representative samples from a waste wood collection site (Otto Ddmer, Hamburg) were subjected to fest pyrolysis and analysis. Two classes, H2 and H3, were selected. H2 contains typically particle boards and window frames, H3 consists of railway sleepers, fences, cable dnuns, and other materials impregnated with organic chemicals. 

Tanning, chemical section tanning materials, impregnating and preserving... 

The case in which the explosive was stored was fitted with a narrow metal tube communicating with a glass tube containing a porous material impregnated with litmus or other indicator. The gases evolved by the explosive on storage reacted with the indicator. 

While cassava is an important crop across a wide range of tropical environment, cassava peels are an agricultural waste from the foodprocessing industry. Activated carbon prepared from cassava peel was used as an adsorbent in removal of dyes and metal ions from aqueous solutions. The material impregnated with H3PO4 showed higher efficiency than the heat-treated material (Rajeshvarisivaraj et ah, 2001). 

This observation suggests that the deposition of M0O3 at the surface of the silica proceeds in two distinct steps depending on the amount of material impregnated. 

Ion exchanged Mo-ZSM-5 and Mo-mordenite were prepared in an aqueous solution having a pH below 1.0 and using MoO Cl as the starting material. Impregnated Mo-zeolites were prepared by similar method except at high pH which was controlled by addition of pyridine. A detailed description of the preparation and characterization of the catalyst will be reported elsewhere (ref. 6). 

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