Conventional ceramic method

Single crystals of K NbeOn can be obtained by slow cooling of the melt near 1200°C.4,34,355 Powder samples can be prepared by conventional ceramic methods at about 1100°C. X-ray powder patterns have been reported in the literature.4 The BET surface area of the ceramic preparation85 is typically of the order of 1 m2g-1. Hydrothermal synthesis can be used to prepare the single-nhase oxide at temperatures as low as 280°C with four times the surface area, as reported in the literature.365 Catalytic properties of such preparations have not oeen examined. 

A conventional ceramic method, known as solid-state reaction, consists of a diffusional process for obtaining the ceramic phase from the mechanical mixture of oxides, in pre-set stoichiometric amounts. This process is followed by suitable thermal treatment, generally at high temperature (800-1300 °C). After the thermal treatment, calcining and sintering methods lead to a crystalline and homogeneous product. 

So, Alikhanzadeh-Arani and Salavati-Niasari [5] have reported the preparation of YBaCuO at 870 °C, a temperature somewhat lower than that required in the conventional ceramic method, when starting from [tris(2-hydroxyacetophenato) triaqua yttrium(III)] instead of 2(003)3. 

This is not exactly referring to a synthesis procedure, as the role of microwaves (MW) is merely to increase the rate of the solid-solid reaction and the diffusion rate no other difference exists with the conventional ceramic method. 

The conventional production method for SiC - the reaction of coke and sand (Acheson process) -does not involve soluble or fusible intermediates. For many applications of silicon carbide this fact is not necessarily a disadvantage, but for the preparation of ceramic composites such intermediates are required. 

The conventional industrial method for the synthesis of a-silicon carbide is to heat silica (sand) with coke in an electric furnace at 2,000-2,500 °C. However, because of the high melting point of the product, it is difficult to fabricate by sintering or melt techniques. Thus, the discovery of a lower temperature fabrication and synthesis route to silicon carbide by Yajima and coworkers in 197526,27 proved to be an important technological breakthrough. This is a preceramic polymer pyrolysis route that has been developed commercially for the production of ceramic fibers. 

In contrast to writing, drawing, marking, and conventional printing methods, inkjet printing is a true primary, non-impact process. Liquid ink droplets are ejected from a nozzle under digital control and directed onto surfaces such as paper, plastics, metals, ceramics, and textiles to form a character or image [2,3],... 

Yttrium barium copper oxide has been prepared in a number of ways using both conventional ceramic and coprecipitation methods. The classic laboratory method uses yttrium oxide, barium carbonate (not barium oxide as it is hygroscopic) and copper oxide. 

Some a-Al203-based filter discs (Schumacher, Germany) were vacuum impregnated with a solution containing appropriate amounts of nickel nitrate and urea. After the excess solution was drained off, the discs were placed in a closed vessel and kept at 90 °C for a certain period, resulting in precipitation of nickel precursor by the slow hydrolysis of urea in the pores of the discs. After reaction, the filter discs were dried at 110 °C for a few hours and calcined at 450 °C for 4 h. Then the nickel-modified ceramic filter discs were obtained. For the conventional impregnation method, other steps and experimental conditions were identical to the preparation procedure with the urea method except for the absence of urea in the impregnation solution. 

Ferrites can be prepared by almost all the existing techniques of solid state chemistry, leading to a very wide variety of forms polycrystalline aggregates, thin and thick films, single crystals. Some of these methods have been developed to prepare ferrites with specific microstructures. The oldest one, the ceramic method, involves the same operations as the classical techniques for fabrication of conventional ceramics. This explains the origin of the term magnetic ceramics. Many of the techniques recently developed consist of improvements in one or several of the basic operations of ceramic fabrication. 

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