Ceramic spheres

Formation of spherical, micron-sized ceramic particles was investigated in an RF thermal plasma reactor. It has been concluded that a wide size distribution of feedstock powders gives rise to either excessive evaporation of smaller grains or insufficient melting of bigger ones. Ceramic spheres with more or less voids inside can also be prepared starting from powders pretreated in special ways. 

The feed is then passed through a stacked series of three or four reactors containing the catalyst (platinum chloride or rhenium chloride supported on silica or silica-alumina). The catalyst pellets are generally supported on a bed of ceramic spheres. 

In a separate experiment two pilot plant reactors were connected in series. Each reactor was half filled with catalyst and half filled with inert ceramic spheres. The tail gas from the first reactor was fed into the second reactor after condensable products (H20, liquid products) had been removed. Following reaction, the catalyst was unloaded in sections from both reactors under nitrogen as described for the study involving the single reactor. 

A blackened ceramic sphere of 10 cm diameter is initially uniform in temperature at 1000°K and is suddenly placed in outer space where it loses heat by radiation (no convection) according to... 

Fig. 17 Cell resistances measured by Hyde and Welch on a model cell. Resistance is reported as a function of interelectrode gap with three large ceramic spheres (simulating gas bubbles) in the electrolyte, 6 large spheres, 6 large and 44 small spheres, or no spheres [40].

Names ceramic beads, ceramic spheres, microspheres... 

Fillers play an important role in powder coating of polyamide to form articles with a metal-like look (e.g., handles, mountings for radiators and pipes). For a material to be powder coated, it must withstand the stoving temperatures (170°C or more). It must also be electrically conductive, be chargeable and its reactive groups must be able to link with the coating system. Fillers such as metal and metal coated ceramic spheres and carbon fibers are added to polyamide for its strength and paintability. 

Considering a TiC ceramic sphere as shown in figure 4, uniform load qi, the radius is equal to a. 

The determination of the interface stress When the temperature varies, the TiC ceramic sphere and NisAl spherical shell are deformed simultaneously. The displacement of the interface between TiC sphere and NisAl spherical shell are equal, namely, it must satisfy the condition of compatibility of the interface displacement, and the radial stress is equal and opposite in the interface.It can be written as R1 r2 (14)... 

Catalytic activity data were obtained by using a conventional fixed-bed reactor at atmospheric pressure. A stainless steel tube with an inner diameter of 12 mm was chosen as the reactor tube. Catalyst (3.5 cm, ca. 1.8 g) was placed on ceramic wall at the lower part of the reactor. The upper part of the catalyst bed was packed with 10 cm of inactive ceramic spheres (2 mm O.D.) to preheat the gas feed. The furnace temperature was controlled with a maximum variation of 2°C by an automatic temperature controller. The gas exiting the reactor was led to a condenser to remove water vapour. The remaining components were continuously analysed by non dispersive infrared (CO and CO2), flame ionisation (HC), magnetic susceptibility (O2), and chemiluminiscence (NOx). 

THE NOTCHED BALL TEST -ANEW STRENGTH TEST FOR CERAMIC SPHERES... 

The Notched Ball Test—A New Strength Test for Ceramic Spheres... 

A. A. Wereszczak, T. P, Kirkland, and O. M. Jadaan, "Strength Measurement of Ceramic Spheres Using a Diametrally Compressed "C-Sphere" Specimen", Journal of the American Ceramic Society, vol. 90, pp. 1843-1849, 2007. 

Other inorganic antiblocking fillers such as calcium carbonate, alumina-silicate ceramic spheres, zeolite, kaolin day, feldspar, and mica have also been used as antiblocks. In PE film, caldum carbonate can provide the low blocking force of talc and DE, but only when loaded at 2-3 times their concentration (or higher), reducing darity of the film, and increasing its density [12-1, 12-22, 12-30]. 

Antiblock agent Talc, mica, ceramic spheres Prevents sticking of films... 

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