Zinc Oxide—From Synthesis to Application: A Review - MDPI
In this review, the methods of synthesis, modification and application of zinc oxide will be discussed. The zinc oxide occurs in a very rich variety of structures and offers a wide range of properties. The variety of methods for ZnO production, such as vapour deposition, precipitation in water solution, hydrothermal synthesis, the sol-gel process, precipitation from microemulsions and mechanochemical processes, makes it possible to obtain products with particles differing in shape, size and spatial structure. These methods are described in detail in the following sections ().
Paul Taylor Dance Company Aureole images
In processes of synthesis of nanopowders based on precipitation, it is increasingly common for surfactants to be used to control the growth of particles. The presence of these compounds affects not only nucleation and particle growth, but also coagulation and flocculation of the particles. The surfactant method involves chelation of the metal cations of the precursor by surfactants in an aqueous environment. Wang  obtained nanometric zinc oxide from ZnCl2 and NH4OH in the presence of the cationic surfactant CTAB (cetyltrimethylammonium bromide). The process was carried out at room temperature, and the resulting powder was calcined at 500 °C to remove residues of the surfactant. The product was highly crystalline ZnO with a wurtzite structure and with small, well-dispersed spherical nanoparticles in size of 50 nm. It was found that CTAB affects the process of nucleation and growth of crystallites during synthesis, and also prevents the formation of agglomerates.
This paper describes a generic speech synthesis system called CHATR which is being developed at ATR. CHATR is designed in a modular way, module parameters and even which modules are actually used may be set and selected at run-time. Although some interdependencies exist between modules, CHATR offers a useful research tool in which functionally equivalent modules may be easily compared. It also acts as a simple system for those less interested in the internals of speech synthesis but just wish their computer to talk. Topic: speech synthesis, generic systems. Introduction There are many requirements for a speech synthesis system, in addition to high quality natural sounding speech output, the system should be flexible and not simply be hard-wired. For example it should at least be the case that new words can be added to the lexicon. Other more general changes should also be possible e.g. specification of new intonational tunes, varying of output voices, choice of phoneme set to be used...