progress in nanotechnology, 2002, p.308

[...]... partly because the cofired firing temperaf ture is too high Decreasing the sintering temperature o cofired ceramic tape by including alumina nanofibers and minimizing or eliminating the organic binders in the tape might allow copper to be used The interstices (pores) produced by cold pressing these fibers are likely to be less than -10 nm Subsequent sintering would shrink such pores further and provide... now condensing particles.) Particles quench as they condense and begin to disperse in the expanding and cooling combustion flow Finally, nonagglomerated nanoI5 particles collect on a moving cold finger or on the reactor wall The beauty of the process is that a flat burner is naturally scaleable in a linear or radial fashion In fact, scaling rules are simple Essentially, one need only to maintain a constant... products have made headway into the marketplace Also, the promising photocatalyst market for nanocrystals is beginning to generate revenues mainly because of development projects and new product introductions by companies in Japan and Europe The U.S Navy has increased interest in thermal spray applications for nanoparticulate feedstock, and progress also has been made in exploiting the characteristics... wire began in 1774 In the 1970s, a f group in Tomsk innovated the EEW process by exploding wire in inert- or hydrogen-gas atmospheres within a chamber In the mid 1990s, Argonide invested in this technology in exchange for exclusive sales and manufacturing rights In 2000, the U.S Department of Energy provided additional funds to support this project The project involves three U.S National Laboratories-National... sintering aids When the fibers are heated from -400 to 900"C, they lose -7536 of their surface area, sugesting that the sintering process is well underway Preforms containing the fibers can be made by mulching and filtering them through a cellulose ultrafilter The green strength The American Ceramic Society of such mats is sufficient for handling and subsequent sintering, even without an organic binder... nanopowders has increased dramatically in recent years with the growth of applications in the cosmetics and chemical mechanical polishing (CMP) industries Other applications include luminescent materials, chemical gas sensors, multilayer ceramic capacitors and heat transfer fluids Since established technologies are beginning to use nanopowders instead of coarser particles, the market is growing rapidly... condensation In order to produce loosely agglomerated particles, wet chemical processes generally require the use of a surface coating In some applications, the coating may be a desirable feature For most applications, however, a coating complicates subsequent processing because the coating becomes a processing contaminant A major step in the forming of loosely agglomerated particles is the introduction... surface coatings Nanocopper can be sintered to fully dense, low electrical resistivity (-2 mW-cm), thick films at 500°C The potential for combining low-sintering-temperaturesubstrates using nanofibers with low-temperature sintering o nanocopper might produce a f low-cost and highly effective LTCC process Approximately 60 Russian scientists are involved in nanometal R&D Recently, the R&D effort was increased... particlelbinder interface energy was proposed to account for this observation I Introduction R into the possibility of producing three-dimensional non-oxide engineering ceramics-especially nanocomposites based on silicon nitride (Si,N,) from the pyrolysis of polymer precursors has intensified over the past two decades.'-3 The increased emphasis on this processing method comes from the possibility of obtaining... The polymer powder was placed into an alumina boat and heated at a rate of 10"C/min in a quartz tube furnace in flowing nitrogen (gas flow of 150 cm'/min) When the predetermined ammonia treatment temperature (T,) was attained, the flowing gas was switched from nitrogen to ammonia (150 cm'/min), and the temperature was held at T, for 1 h After the ammonia treatment, the flowing gas was switched back to . the pyrophoricity of the high-surface-area particles). mony tin oxi 5 e (Sb203-Sn02 or Nanoparticle Pricing Despite progress in scaling up production and reducing costs, nanoparticles. were present in the PbO phase at 400°C. A phase-pure tetragonal- perovskite-type material was formed at 420°C. Sharper XRD peak patterns resulted from higher preparation temperatures. Particle. ceramic tape by including alumina nanofibers and minimizing or eliminating the organic binders in the tape might allow copper to be used. are likely to be less than -10 nm. Subsequent sintering