This paper reviews the past, present, and future of the hydroxyapatite (HAp)-based biomaterials from the point of view of preparation of hard tissue replacement implants. Properties of the hard tissues are also described. The mechanical reliability of the pure HAp ceramics is low, therefore it cannot be used as artificial teeth or bones. For these reasons, various HAp-based composites have been fabricated, but only the HAp-coated titanium alloys have found wide application. Among the others, the microstructurally controlled HAp ceramics such as fibers/whiskers-reinforced HAp, fibrous HAp-reinforced polymers, or biomimetically fabricated HAp/collagen composites seem to be the most suitable ceramic materials for the future hard tissue replacement implants.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0884291400042527

Processing and properties of hydroxyapatite-based biomaterials for use as hard tissue replacement implants

https://iopscience.iop.org/article/10.1016/j.stam.2003.09.002/pdf

Recent research and development in titanium alloys for biomedical applications and healthcare goods

This paper reviews the present knowledge on tantalum pentoxide (Ta 2 O 5 ) thin films and their applications in the field of microelectronics and integrated microtechnologies. Different methods used to produce tantalum oxide layers are described, emphazing elaboration mechanisms and key parameters for each technique. We also review recent advances in the deposition of Ta 2 O 5 in the particular field of microelectronics where high quality layers are required from the structural and electrical points of view. The physical, structural, optical, chemical and electrical properties of tantalum oxide thin films on semiconductors are then presented and essential film parameters, such as optical index, film density or dielectric permittivity, are discussed. After a reminder of the basic mechanisms that control the bulk electrical conduction in insulating films, we carefully examine the origin of leakage currents in Ta 2 O 5 and present the state-of-the-art concerning the insulating behaviour of tantalum oxide layers. Finally, applications of tantalum oxide thin films are presented in the last part of this paper. We show how Ta 2 O 5 has been employed as an antireflection coating, insulating layer, gate oxide, corrosion resistant material, and sensitive layer in a wide variety of components, circuits and sensors.

Tantalum pentoxide (Ta2O5) thin films for advanced dielectric applications

Provided is a surface-coated cutting tool combining superior heat resistance, superior wear resistance, and superior lubricity. A surface-coated cutting tool of the present invention includes a substrate and a coating formed on the substrate, and the coating is characterized in that the coating is formed by physical vapor deposition and includes one or more layers, that at least one of the one or more layers is a first coating layer, and that the first coating layer contains aluminum and nitrogen, has a thermal effusivity of 2,000 to 5,000 J·sec −1/2 ·m −2 ·K −1 , has a thickness of 0.2 to 5 μm, and has a crystal structure including a hexagonal structure.

Surface coated cutting tool

Non-faradaic electrochemical modification of catalytic activity: A status report

Catalytic Decomposition of Hydrogen Sulfide

Possibility for effective production of hydrogen from hydrogen sulfide by means of a porous Vycor glass membrane

Production of hydrogen from hydrogen sulfide by means of selective diffusion membranes

The thermal decomposition of sulfuric acid is used as a step in the oxygen evolution in some thermochemical water-splitting cycles. The catalytic activity of metal oxides was studied in an attempt to find some suitable catalysts for sulfuric acid decomposition. The catalytic activity of SiO2, Al2O3, ZnO, CuO, NiO, CoO, Fe2O3, MnO, Cr2O3, V2O5, TiO2 was measured at high temperatures (800–870 °C and at atmospheric pressure. Iron(III) oxide was found to have the highest activity as a catalyst. Low catalytic activity was observed for the oxides (Al2O3, ZnO, NiO, CoO, MnO) which change to their sulfates under the present reaction conditions. Since the reaction conditions were very severe (more than 800 °C and in the presence of steam), a rapid decrease in both the specific surface area and the catalytic activity was observed. In order to avoid these disadvantages and in order to prepare practically useful catalysts, iron(III) oxide was pelletized and sintered (1000 °C, 6 h). Upon this procedure, this catalyst ...

Tetsuya Kameyama

Papers

Catalytic Decomposition of Hydrogen Sulfide

Possibility for effective production of hydrogen from hydrogen sulfide by means of a porous Vycor glass membrane

Production of hydrogen from hydrogen sulfide by means of selective diffusion membranes

The Study of Thermochemical Hydrogen Preparation. III. An Oxygen-evolving Step through the Thermal Splitting of Sulfuric Acid

Stoichiometry of tantalum oxide films prepared by KrF excimer laser-induced chemical vapor deposition