Porous hydroxyapatite (HA) and beta-tricalcium phosphate (β-TCP) blocks are well known biomaterials employed as bone substitutes. Control of the porosity and morphology of these ceramics are important in governing their biological properties upon implantation. One synthetic method, hydrothermal processing, produces porous ceramics with distinct morphologies. In the present study, porous calcium phosphate blocks with unique structures were produced from compacted powder mixtures of alpha-tricalcium phosphate (α-TCP) and glycine (Gly) treated by exposure to water vapor at 120, 160, and 200°C for 5 h. Hydrothermal treatment at 200°C for 5 h of mixtures of Gly/α-TCP with mass ratios of 50/50 and 67/33 could give the porous materials of single phase HA. The obtained porous HA blocks had micrometer-sized pores due to the entanglement of rod-shaped particles, and large-sized pores of over 100 µm in diameter derived from Gly. After the heating at 900°C for 3 h in air, HA was converted to β-TCP with almost same microstructure in comparison with that of pre-heating one. The present methods provided insight into the production of porous blocks composed of rod-shaped calcium phosphate particles with both submicron-sized pores and large-sized pores of about 100 µm in size.

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Microtubular solid oxide fuel cells were fabricated by the multi-dip coating of ceramic aqueous slurries on steel wire. This is a very convenient way to make small straight tubes without requiring special handling. Prepared NiO-GDC/GDC double layered tubes were separated by dissolving the pre-coated polystyrene layer in organic solvent, then were sintered at 1350°C. Then a cathode layer of LSCF-GDC was also formed on the double layered tubes with heat treatment at 1100°C. The prepared microtubular cell performs with a maximum power density of 0.34 W/cm² at 550°C. Microstructure observation of the tubes suggested the possibility of further improvement in cell quality.

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Highly efficient Eu:YV_1−xP_xO₄ phosphor particles, ∼200 nm in size, were synthesized using a new synthesis technique. The resulting particles exhibited higher photoluminescence efficiency than the micron-sized commercial sample, highlighting their high quality. To the best of our knowledge, such high efficiency has not been achieved without a surface and heat treatments. In addition to the photoluminescence spectrum, high resolution transmission electron microscopy (HRTEM) demonstrated perfect crystallinity with clear lattice fringes.

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Antimicrobial activities of porcelain glazes with antimicrobial agents made of clay minerals intercalated with silver chelate and the effect of additives to the antimicrobial agents on those activities were investigated. The glazes with 10 mass % antimicrobial agents, fired at 1573 K in a reducing atmosphere, showed negative antimicrobial activities. On the other hand, the antimicrobial activities of the glazes with 1–10 mass % of the agents fired in an oxidizing atmosphere were positive. The glaze with an agent doped with Zr had a high antimicrobial activity by adding only 0.2 mass % of the agent, which included only 0.008 mass % Ag in the glaze. Wavelength-dispersive X-ray fluorescence, used for ingredient analysis, showed that the negative activity resulted from the disappearance of the Ag in the glaze fired in the reducing atmosphere.

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Maskless and electroless patterning of gold was performed by a simple method: 3-mercaptopropyltrimethoxysilane (MPTMS) and an aqueous solution of hydrogen tetrachloroaurate (HAuCl₄·4H₂O) were reacted, and the obtained solution was dropped onto a silicon substrate processed by a focused ion beam (FIB). This method utilizes the selective growth of gold nanoparticles on an FIB-processed area of a silicon surface. Raman microspectroscopy revealed that gold nanoparticles selectively grew on an FIB-processed area when an amorphous silicon phase was induced by an FIB. Unlike other attempts to fabricate metal patterns with silane coupling agents, MPTMS acts as a reducing agent, not as glue.

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In this work crystallization kinetics of hydroxyapatite (HAP) were investigated in the presence of a biodegradable, environmentally friendly polysaccharide-based polycarboxylate, carboxymethyl inulin (CMI), under strictly controlled temperature, pH, and atmospheric conditions. The constant-composition method has been used to study the influence of biopolymers of crystal growth of HAP, on HAP seed crystals at pH 7.4 and 37°C. The results indicate that polymer concentration and the larger number of negatively charged functional groups markedly affect the growth rate. Biopolymer affects the coherence length of the crystalline domain. The decrease in growth rates was substantiated by SEM which showed smaller crystal sizes as a function of increasing carboxylation degree of the CMI and its concentration.

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Titanium metal, which is used as artificial bone, has a titania surface layer. In this study, titania was investigated using surface plasmon resonance (SPR) in terms of protein adsorption, which occurs during the initial process of cellular attachment by employing a multilayer device consisting of a titania layer on Au. The titania film was deposited on the Au layer in the multilayer device by atmospheric chemical vapor deposition. A flow cell was used to evaluate protein adsorption on the titania top layer of the multilayer device. Phosphor buffer solutions with and without the protein lysozyme (Lyz) were injected into the flow cell. From the attenuation of reflected light, the SPR angle was determined as the angle with minimum reflection intensity. The observed behavior of the SPR angle indicated that Lyz was adsorbed on the titania film surface, and the obtained SPR angles increased with the Lyz concentration on the titania surface. These results indicate that the titania/Au multilayer SPR device can easily be used to detect the adsorption of protein.

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TiO₂-coated SiO₂ particles were prepared using industrially-wasted amorphous SiO₂ particles by an alkoxide method. The amorphous SiO₂ particles were used as support for TiO₂ photocatalyst. The mean size of the amorphous SiO₂ particle was approximately 100 nm. The major synthesis parameters were a kind of alcohol solvent (methanol, ethanol, and 1-propanol) and calcination temperature. The SiO₂ particles and titanium tetraisopropoxide were mixed in an alcohol solvent and an appropriate amount of distilled water was added to the suspension for hydrolysis of the alkoxide. The precipitate was calcined in the temperature range from 600 to 1300°C to crystallize the deposited TiO₂. The samples were characterized using XRD, BET and TEM-EDS analyzer. It was found that the use of SiO₂ support, methanol solvent in hydrolysis of Ti alkoxide and freeze-drying of product were effective to keep the anatase phase at high calcination temperature even though the crystallite size of anatase increased and the specific surface area decreased. As a result, the maximum decomposition ratio of methylene blue was obtained on the TiO₂-coated SiO₂ particles synthesized in methanol solution and calcined at 1000°C.

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This study investigates the effect of B₂O₃ on the sintering behaviour, dielectric properties and microstructure of Ba_0.6Sr_0.4TiO₃ + 0.6% CuO (BSTC) ceramics. Ceramics were sintered in air at temperatures ranging from 900 to 1150°C. There are two kinds of secondary phases produced in BSTC ceramics during B₂O₃ addition; one is BaCuB₂O₅ with a melting point of approximately 850°C, and the other is BaTi(BO₃)₂ with a melting point of ∼749°C. The amount of secondary phase present was seen to increase as the amount of B₂O₃ additives increased. The BSTC ceramics with 1 mass % B₂O₃ sintered at 1000°C in air for 2 hours exhibited a maximum permittivity, ε_max = 1826, and a bulk density >95% of theoretical density. Moreover, 0.5 mass % B₂O₃ doped BSTC sintered at 1000°C exhibits a maximum permittivity, ε_max = 2100, and a bulk density >92% of theoretical density.

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A 10Na₂S·30B₂O₃·60SiO₂ (mol %) glass was prepared, and the changes in glass structure and chemical state of sulfur caused by phase separation were investigated. In the as-prepared and heat-treated glasses, sulfur was present as S²⁻ anion and polysulfide S₂⁻ and S₃⁻ anions, and Si–S and B–S bonds were not confirmed. A phase separation by spinodal decomposition was observed after heat-treatment, where sulfur was preferentially distributed to borate-rich phase. Even after the phase separation, formation of non-bridging oxygen was not recognized. The preferential distribution of sulfur anions in the present glass was explainable on the basis of the change in population of sodium ions, which compensated the negatively-charged sulfur anions.

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Porous alumina with uniform microstructure was prepared using needle-like boehmite particles. A procedure for improving its thermal stability was examined. Uniform, needle-like boehmite particles were synthesized using a hydrothermal procedure. Porous boehmite was prepared using vacuum filtration of boehmite aqueous suspension. Porous alumina was prepared by heat treatment of the porous boehmite. During heat treatment at 1200°C for 2 h, the specific surface area of the porous boehmite decreased to about one-twentieth (8 m²/g) of the as-prepared porous boehmite. To improve the thermal stability of the porous alumina, La addition to the porous boehmite surface was conducted merely by filtrating La aqueous solution using the porous boehmite itself. The porous alumina with 1.1 mol % of La showed specific surface area of 46 m²/g, even after heat treatment at 1200°C for 2 h.

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Silver conducting films are formed by ink-jet printing method from the silver colloidal inks with and without glass powders. Bi-based glass powders with nanometer size prepared by flame spray pyrolysis are used as an inorganic binder. The silver conducting film formed from the ink without glass powders had island structure at a firing temperature of 450°C. On the other hand, the silver conducting film with 5 wt % glass content of silver component had clean surface, dense structure, fine grain size and good adhesion property to the glass substrate. The silver conducting films with 1, 3 and 5 wt % glass contents had low specific resistivities at a firing temperature of 450°C of 2.6, 2.7 and 3.1 µΩ cm, respectively.

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A novel method was developed for preparation of Ca₃Al₂O₆ which is one composition of Portland cement-based mineral trioxide aggregate for endodontic treatment. Only Al(NO₃)₃·9H₂O and Ca(NO₃)₂·4H₂O as raw materials and ethanol as solvent were needed in the whole process. The consequent dry Ca₃Al₂O₆ precursor was examined by thermal analysis and the as-burnt powders calcined at different temperatures for 3 hours were measured by X-ray diffractometry. Pure phase Ca₃Al₂O₆ with particle size of 1–10 µm was obtained at 1100°C and highly pure Ca₃Al₂O₆ (>99.5%) was obtained at 1350°C. Therefore, this method is useful for preparation of pure Ca₃Al₂O₆ for biomedical applications.

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Tin phosphide (SnP_0.94) particles were synthesized by thermal decomposition of tin acetate in a mixed solution of trioctylphosphine and a high-boiling solvent. Teardrop-shaped SnP_0.94 particles with the size of about 500 nm were obtained by using trioctylphosphine oxide as a coordinating solvent. In the case using oleylamine as a solvent, the shape of SnP_0.94 particles was not uniform. Formation mechanism of teardrop-shaped SnP_0.94 was discussed. SnP_0.94 particles prepared by using the trioctylphosphine oxide as a coordinating solvent were applied as an active material to all-solid-state lithium cells. The cell Li–In/80Li₂S·19P₂S₅·1P₂O₅/SnP_0.94 exhibited the initial discharge capacity of 1000 mAh g⁻¹ at a current density of 1.3 mA cm⁻².

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Siloxane-containing vaterite (SiV)/poly (L-lactic acid) (PLLA) hybrid (SiPVH) fibermats have superior potential for bone regeneration applications. Present work aims to optimise its performance as bone filler materials by improving its mechanical properties and maintaining its bioactivity. The SiPVH fibermats were prepared with melt-blending and electrospinning protocols and modified by increasing PLLA content from 40 to 70 wt %. The tensile strength of the modified fibermat was 10 times higher than that of the original one. The elongation before failure of the modified fibermat was twice as large as that of the original one. The mechanism of their enhancement was investigated by observing failure points in the fibermats after the tensile tests: necking of fibers, which occurred in the modified fibermats, was believed to contribute to the enhanced mechanical properties. The modified fibermat showed the relatively constant release of ionic silicon-species in Tris-buffer solution and could be coated with hydroxyapatite by soaking in simulated body fluid.

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