Biomedical components production

The deposition of pyrolytic graphite in a fluidized bed is used in the production of biomedical components such as heart valves, ] and in the coating of uranium- and thorium-carbides nuclear-fuel particles for high temperature gas-cooled reactors, for the purpose of containing the products of nuclear fission.fl" The carbon is obtained from the decomposition of propane (CgHg) or propylene (CgHg) at 1350°C, or of methane (CH4) at 1800°C. Its structure is usually isotropic (see Ch. 4). 

Fluidised-bed CVD is a special technique to coat nuclear-fuel particles for high-temperature gas-cooled nuclear reactors which was developed in the late 1950s. This technique has also been used in other applications, such as the production of biomedical components (e.g. heart valves deposited by pyrolysis carbon) and some special functional coatings on ceramic particles. 

The meyor applications of pyrolytic carbon deposited by fluidized bed are found in the production of biomedical components such as heart valves and in the coating of uranium carbide and thorium carbide nuclear-fuel... 

Chapters 2 and 3 have been replaced (Basic Principles and Theories of Diffuse Reflection), several chapters (4,19,25,26,29, and 37) have been updated (Commercial Instrumentation, Analyses of Textiles and of Baked Products, Advances in the Petrochemical Industry, Polymers, Pharmaceutical Applications, and Process Analysis), and some new chapters (12,18,21,28,29,31,32,33,35, and 38) have been added (Process Sensors, Agro-Forestry Systems, Gas Analysis, Use of NIR at the Bowling Alley, PAT in the Pharmaceutical Industry, Nutraceuticals, Detection of Counterfeit Drugs (e.g., Viagra), NIR Photography in Medicine, Biomedical Components in Blood and Semm, and The Detection of Counterfeit Currency and Turquoise). 

Many polymer-polymer complexes can be obtained by template polymerization. Applications of polyelectrolyte complexes are in membranes, battery separators, biomedical materials, etc. It can be predicted that the potential application of template polymerization products is in obtaining membranes with a better ordered structure than it is possible to obtain by mixing the components. The examples of such membranes from crosslinked polyCethylene glycol) and polyCacrylic acid) were described by Nishi and Kotaka. The membranes can be used as so-called chemical valves for medical applications. The membranes are permeable or impermeable for bioactive substances, depending on pH. 

Biomedical polymer material is an important component of biological material and is a remarkable functional polymer. It involves in physics, chemistry, biochemistry, medicine, pathology subjects. The synthetic polymer materials and the organisms (natural polymer) have a very similar chemical structure, which determines their similarity in performance and enables high molecular polymer to meet the many complicate and rigorous functional requirements for medical products. Most metal and inorganic materials are incapable in this respect. Presently, high molecular polymers are widely used in medical products. 

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