Glass-Ceramic Methods

The previous discussion has centered on how to obtain as much molecular mass and chemical structure information as possible from a given sample. However, there are many uses of mass spectrometry where precise isotope ratios are needed and total molecular mass information is unimportant. For accurate measurement of isotope ratio, the sample can be vaporized and then directed into a plasma torch. The sample can be a gas or a solution that is vaporized to form an aerosol, or it can be a solid that is vaporized to an aerosol by laser ablation. Whatever method is used to vaporize the sample, it is then swept into the flame of a plasma torch. Operating at temperatures of about 5000 K and containing large numbers of gas ions and electrons, the plasma completely fragments all substances into ionized atoms within a few milliseconds. The ionized atoms are then passed into a mass analyzer for measurement of their atomic mass and abundance of isotopes. Even intractable substances such as glass, ceramics, rock, and bone can be examined directly by this technique. 

Glass-ceramic articles can be fabricated by means of either bulk or powder processing methods. Both methods begin with melting a glass of the desired composition. 

Household waste, 25 864 House-of-cards glass-ceramic microstructure, 12 635 Housewares, LLDPE, 20 207-203 Housewrap, 17 482 Housings, for cartridge filters, 11 369 Hoveya-Grubbs catalysts, 26 934 H-phosphonate DNA synthesis method, 17 624-625... 

Primenko, V. L, Theoretical method of determining the temperature dependence of the thermal conductivity of glasses. Glass Ceram., 37, 240-242 (1980). 

Production. There are three important methods for manufacturing barium ferrite on an industrial scale the ceramic, hydrothermal, and glass crystallization methods. The main producers are Toshiba and Toda. 

Soil - Food grease, oil and protein, petroleum grease and oil Surface - Metal, ceramic, polymeric, glass Application Method - Spray and wipe Manufacture - Mix tank with propeller stirrer... 

Methods for manufacturing different fibre-reinforced glass/glass-ceramic matrix composites... 

CDM 105 is a proprietary glass-ceramic, manufactured by the freeze gelation method, figures in parentheses are standard deviations. 

Excimer Laser Micromachining [132, 133] is a technique based on laser ablation. Currently, this process can routinely ablate vias as small as 6 pm in diameter in polymers, glass, ceramics and metals. The minimum size of the features that this method can produce is limited by diffraction and by heat/mass transport. Commercial instruments and services are available from a number of companies (for example, Resonetics, Itek). 

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