SUBJECTS magnesia

In the examination of ores of the second claw, charcoal atone is insufficient to effect the decomposition, and therefore a flux Is employed which, by combining with the silieious matter, liberates the oxide of zinc, and renders it subject to reduction by the carbonaceous matter. Lime or magnesia are tho agsuts usually adopted,. 

If iron is present, the dry residue is subjected for several weeks to sunlight which renders the iron insoluble in acetic acid, after which acetic acid dissolves the calcium and magnesium carbonates which are separated by dilute sulphuric acid, precipitating calcium and dissolving magnesia. The residue from acetic acid treatment consists of clay, silicious matter and iron. The clay and iron are dissolved by marine acid (hydrochloric) and the iron precipitated by caustic alkali (phlogisticated alkali) and the clay by alkali carbonate. The silicious matter may be identified by its complete solution with effervescence under the blowpipe with mineral alkali (sodium carbonate). 

Many of the catalysts for the hydrodesulfurization process are produced by combining (Table 5-5) a transition metal (or its salt) with a solid support. The metal constituent is the active catalyst. The most commonly used materials for supports are alumina, silica, silica-alumina, kieselguhr, magnesia (and other metal oxides), as well as the zeolites. The support can be manufactured in a variety of shapes or may even be crushed to particles of the desired size. The metal constituent can then be added by contact of the support with an aqueous solution of the metal salt. The whole is then subjected to further treatment that will dictate the final form of the metal on the support (i.e., the metal oxide, the metal sulfide, or even the metal itself). 

Tariff Commission, War Changes in Industry, 1943-1949. Series of 29 booklets on various chemicals and commodities. Subjects include wool, alcohol, rubber, magnesium, magnesia, aluminum, petroleum, dyes, plastics products, el al. 

The lowest temperatures of Pt reduction were recorded in the case of catalysts deposited on titania, whereas the highest for catalysts deposited on magnesia. An interesting phenomenon was observed in the case of catalysts deposited on silica. The consumption of hydrogen by these systems was very low. This was probably due to the high degree of platinum dispersion on it. The elucidation of this phenomenon will be the subject of a forthcoming paper. 

Detailed laboratory and field studies have shown that Paraho retorted shale can be compacted easily is not subject to dusting, erosion, or auto-ignition and can be handled to create structures of very low permeability. A basis for these beneficial properties can be found, in part, by an examination of the chemical and physical properties of the retorted shale. For example, it is believed that the strengths achieved are caused by the hydration of magnesia, reactions of the gypsum minerals, and the compaction of the silty-gravel mix. 

Magnesium hydroxide (Milk o/Magnesia) 15 mL taken with and 3 hours after a single dose of dicoumarol was found to raise the peak plasma levels and AUC of dicoumarol by 75% and 50%, respectively, in 6 healthy subjects. Conversely, aluminium hydroxide (Amphogel) 30 mL did not alter dicoumarol levels. ... 

Experiments and Observations on the following subjects, i. On the preparation, calcination and medicinal uses of Magnesia Alba. 2. On the Solvent Qualities of Calcined Magnesia. 3. On the variety in the Solvent Powers of Quick-Lime, when used in different quantities. 4. On Various Absorbents, as promoting or retarding putrefaction. 5. On the comparative Antiseptic Powers of Vegetable Infusions prepared with Lime, etc. 6. On the Sweetening Properties of Fixed Air London, 1773, xvi (errata), 142 pp. 

The magnesia crystallites in the basic carbonate pseudomorphs appear to be much less subject to mutual constraint through close packing and intergrowth than in the case of the hydroxide relics, and this looser texture favors a higher degree of sinterability. 

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