We have investigated the relationship among thermal properties and mechanical properties of the amorphous carbon films containing nitrogen prepared by the RFplasma enhanced CVD. Thermal conductivity was measured by the 3 w method and related with In!I0 from the Raman spectroscopy, N/C and density from the RBS/ERDA and hardness from the nanoindentation method. The thermal conduction in the films was discussed in terms of the graphite cluster size La derived from the Inllo and correlated with the mechanical properties and tribological properties.

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We previously demonstrated the biotransformation of prenyl alcohols into the corresponding carboxylic acids by cultured cells of Cucurbita maxima. Here, we further investigated two kinds of biotransformation by these cultured cells using combinations of prenyl alcohols and isopentenol and of prenyl diphosphate and isopentenyl diphosphate. The major material formed in the biocatalytic reaction of geranyl diphosphate with isopentenyl diphosphate as substrates was geranylgeraniol, with not only farnesol but also geranylfarnesol also formed, although as minor materials. With the combination of geraniol and isopentenol, in contrast, geranylgeraniol was formed, but neither farnesol nor geranylfarnesol was detected.

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Carbon membranes were prepared by coating thin layers of lignocresol derived from Hinoki cypress by the phase-separation method and then carbonizing the lignocresol by high frequency induction heating at a heating rate of 500°C/min. The thickness of the membrane formed on the outer surface of a porous alumina substrate was about 1000 nm. Carbon membrane with a high performance of gas permeation showed a high water-selectivity in pervaporation of water/alcohol separation. The separation factor increased with increasing the heating temperature. The water concentration of the permeate was more than 99.5 wt% and the water flux was more than one or two order larger than the alcohol flux in the membrane prepared at 600 or 700°C. Carbon membranes derived from lignin-based materials provide one of the promising candidates for the separation of the liquid mixtures

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X-ray absorption fine structure (XAFS) analysis was applied to identify the chemical state of silver and zinc in the glaze of anti-bacterial ceramics. Anti-bacterial ceramics for example tile and sanitary ware are very important from the view point of hygiene. Ag and Zn have been known as inorganic anti-bacterial agents for a long time, and are widely used as raw materials for the anti-bacterial ceramics. These anti-bacterial agents were incorporated into the amorphous alminosilicate glaze. The anti-bacterial activities of the ceramics were confirmed by film covered method using Staphylococcus aureus. Ag K-edge XAFS analysis showed that the chemical state of Ag atoms in the Ag-glaze were monovalent, and the Ag-O bond length was increased compared to that of Ag2O. Zn K-edge XAFS analysis showed that the chemical state of Zn atoms in the Zn-glaze were quite similar to that of Zn2SiO4.

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Carbonization of wood loaded with nickel at 900°C for l h could effectively produce crystallized mesoporous carbon with good electroconductivity and liquid phase adsorption capacity. Concurrently oil fraction was decomposed and deoxygenated into small molecules and a large amount of hydrogen-rich gas was evolved. These situations indicated the successful eo-production of highly functional carbon and upgraded fluid fuels, thus confirming that the catalyzed carbonization is promising as a thermochemical conversion means of wood.

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Sewerage sludge sampled at Gunma Prefectural Central Sewage Disposal Plant was carbonized at 500 °C and activated at 850 °C. The resulting carbon material contained 55 wt.% of ash and its specific surface area was around 126 m2/g. When the carbon material was treated with nitric acid, sulfuric acid, hydrochloric acid, it was suggested that the ash content was reduced to 24~25 wt.% and that nitric acid showed slightly superior performance for the modification. It was also observed that the formation of meso-pores (5 ~ 10 nm), and increase of gross pore volume were made on the material treated with nitric acid. Finally the specific surface area was reached 263 m2/g and as a result the adsorbed amount of benzene on the treated material was improved 2.0 fold as much as that in the untreated one. The additional formation of meso-pores may suggest that the bi-modal structure was appeared in the carbon materials.

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Used lubricant for precision mechanical machining includes a considerable amount of very fine metal particles. Incorporation of the fine particles is a factor of the deterioration of the lubricant. If it were possible to remove the particles effectively, the used oil could be reused. Many attempts have been done to remove the metal particles using several methods, i.e., sedimentation, filtration and centrifugation. Since the viscosity of the used oil is quite high, those methods are not suitable to separate metal particles thoroughly. We found that the metal particles migrated under the high electric field and aggregated on the electrode. After the treatment by the high electric field, the transmittance value recovered to about 75% of that of the original oil. The kinematic viscosity of the treated oil was almost the same as that of the virgin oil. The chemical structure of the cutting oil and additives were hardly degraded by the regular use of the lubricant and the treatment of high electric field. The application of the high electric field is a useful method to remove the metal particles effectively.

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Increasing use of clean photovoltaic energy generation is being looked as a key measure to prevent global warming, but with a conversion efficiency of about 15%, solar cells are not yet up to the task. Moreover, the conversion efficiency of solar cells decreases with temperature rise caused by solar infrared radiation, and necessary visible radiation is reduced by 8% with the solar cell's cover glass. In this study we developed and evaluated optical multilayer thin films to reduce the infrared-caused temperature rise and to improve the transmission of visible light to solar cells. The optical multilayer thin films were designed using Essential Macleod simulation software, prepared with radio frequency (RF) sputtering equipment, and their transmission characteristics were evaluated. The in-operation temperature change and the current-voltage (I-V) characteristic curves of solar cells were measured with and without the optical multilayer thin films, and the results show that they suppressed the temperature rise and improved efficiency of solar cells.

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Removal of phosphate ion in swine urine is a big concern for an environmental conservation. To solve the problem, phosphate ion absorbent in swine urine was developed using carboxymethy cellulose (CMC) and iron compounds. Mixing CMC with iron salt aqueous solutions resulted in gels as known well. While the gel formation proceeded instantaneously when CMC and ferric salt [Fe(III)] aqueous solution were mixed, the gel was not formed immediately when ferrous salt [Fe(II)] aqueous solution was used. Oxidation of Fe (11) to Fe (Ill) occurs gradually in Fe(II) aqueous solution. However, addition of CMC to the Fe(II) solution promoted the oxidation to Fe (Ill). The rate of gel formation could be controlled by addition of acid to CMC-Fe(II) mixture. The absorbent made of CMC and Fe(II) seemed to be more effective than that made of CMC and Fe(III), in Fe content and phosphate ion removal. The resultant gels reduced the phosphorus content from 457 to 3 mg/l in artificial urine and from 78 to 2 mg/1 in swine urine, respectively. The values fulfill the regulation of effluent from the pigsty.

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Sericin is a water-soluble protein and composed of hydrophilic amino acids and acidic amino acids. The key amino acids in sericin are serine, threonine, aspartic acid, and glutamic acid. Sericin has the antioxidative effect, the tyrosinase inhibitory effect, and the amelioration effect of the atopic dermatitis and the contact dermatitis as well as the moisture retention effect. It is rarely known that sericin contains the spore forming bacteria which are parasitic on the mulberry leaves. Here, sericin was extracted from the cocoon by changing of the extraction conditions and the effects of the conditions were investigated. All sericin can be extracted from the cocoon within 1 h with water when the extraction temperature is higher than l20°C. The sericin molecule was hydrolyzed randomly during the extraction but denaturation of sericin hardly occurred. The extraction temperature is the important factor to obtain high molar mass sericin. The ultrafiltration is the effective method to exterminate the spore forming bacteria and the pore size of 0.45 micro m is enough for the filtration.

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Selective chain propagation of ethene to propene (ETP reaction) was made on silica supported cobalt (Co/SiO2) catalyst. It was suggested that the proper conditions for the chain propagation reaction were close to those for the Fischer-Tropsch reaction. When an equimolecular mixture of 12C2-C2H4 and 13C2-C2H4 was contacted on the catalyst, inter-molecular exchange of methylidene, 12C2-C2H4 + 13C2-C2H4 = 2 13C1-C2H4, namely, metathesis, was not occurred in the ETP reaction. And as a result, the selective chain propagation of ethene to propene without metathesis was successfully achieved on Co/Si02 catalyst.

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We have newly developed a rotating box type multi-facing target sputtering system for fabrication of superconducting tunnel junction devices with both a 1 nm-thick tunnel barrier. For realization of high performance X-ray detector of superconducting tunnel junction devices, a sputtering system has to satisfy conditions such as a low-temperature sputtering, a high plasma density, multi-target sputtering and a compact sputtering. This newly developed rotating box type multi-facing target sputtering system has these characteristics. We have fabricated SiO2 thin films for insulation layer of superconducting tunnel junction devices using this sputtering system, and clarified the low-temperature characteristics of this sputtering system.

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Permanent waving (P), bleaching (B), and bleaching and permanent waving (B&P) treatments have been done up to 3 times on virgin Japanese human hair. The properties of treated hairs were investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and amino acid analysis. The cuticle layers were hardly changed by 3 times of P and B treatments. However, the damage of cuticle was observed for 3 times treated B&P hair. FT-IR spectrum of the original hair showed characteristic features of keratin fiber, i.e., amide I (~1640cm-1), amide Il (~1530cm-1), and amide Ill (~1230cm-1). New weak absorptions corresponding to cysteic acid appeared at ~ 1040 cm-1 and ~ 1180cm-1 on IR spectra of P and B treated hair. For B&P treated hair, the peaks of cysteic acid increased remarkably with increase of treatment times. Amino acid composition for each treated hair hardly changed except for cystine. The amount of the cysteic acid in the various treated hairs increased in order of P L.T. S B L.T. B&P treatments. It was found that the damage of hair is encouraged synergistically by repetition of B & P treatment.

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This study describes the effect of thermomechanical cyclic condition on two-way strain in Ti-Ni-Cu shape memory alloy. The material used in this study is Ti-41.7Ni-8.5Cu(at%) shape memory alloy. The specimen shape is a wire with lmm diameter and 70 mm gage length. The specimen was heat treated at 623K for 3.6ks. The process of the cyclic loading test in this study is loading-unloading-heating-unloading-cooling cycle. The specimen was loaded to given applied strain and subsequently unloaded. And then, the specimen was heated up to 373K or 423K and was kept at the temperature for 0.6ks under the constrained strain condition followed by unloading and cooling under free strain condition. Also, the number of cycles is 30 cycles. This study discussed the effects of heating temperature, applied strain and number of cycles on two-way strain in Ti-41.7Ni-8.5Cu(at%) shape memory alloy. The two-way strain slightly increases with increasing heating temperature. An increase in the maximum applied strain up to 7.5% increases the two-way strain. There is hardly effect of the number of cycles on the two-way strain.

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This work describes the effect of heat treatment on temperature response and recovery stress of Ti-Ni-Cu shape memory alloy. The materials used in this study are Ti-41.7Ni-8.5Cu (at%) alloys which have different cold working ratio (10, 40% ). Heat treatment temperatures of wire specimen are varied from 623 K to 773 K. Heating-cooling tests after pre-strain ranged from 1% to 3% at the isothermal temperature of 263K, are carried out to investigate the thermomechanical behavior of Ti-Ni-Cu alloy. The temperature response is decreased with increasing pre-strain and decreasing heat treatment temperature. However, the recovery stress becomes larger with increasing pre-strain and decreasing heat treatment temperature. On the other hand, there is little effect of heat treatment temperature, cold working ratio and pre-strain on transformation temperature hysteresis.

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The actuators using shape memory alloy can work as an actuator to control or retain positioning without using sensor device. In order to utilize the shape memory effect, the external force is required to deform the shape memory alloy in martensitic phase. For a method to give an external force to, a bias mode and an antagonism mode are used. In this work, the effects of a control displacement and an external load on the positioning characteristics by an antagonism type actuator are investigated. The Ti-Ni-Cu alloy wire is used as an actuator element. The positioning characteristics such as settling velocities, position error, and position stability are discussed in relation to a control displacement and an external load. The results show that settling velocity of an antagonism in heating process is slower than those of two bias mode of a const mass and a bias spring, but in cooling process, settling velocity of an antagonism is faster than those of two bias modes. Furthermore, position error is not affected by an external load. However, position stability in heating process is affected by an external load.

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The purpose of this study is to investigate the heat treatment conditions to fabricate Ti-Ni shape memory alloy by Ti/Ni multilayers. The Ti/Ni multilayers were fabricated by multi-step cold rolling of laminates of Ti and Ni foils. They were heat treated at temperatures between 973K and 1273K. The shape memory characteristics of the samples made by laminate method were measured by X-ray diffraction and differential scanning calorimeter. The Ti/Ni multilayers were alloyed to Ti-Ni at 973 K or higher temperature for 12 h or 24 h. The shape memory characteristics at the room temperature are best for the sample heat treated at 1173 K for 24 h among all studied samples.

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A hard/soft magnetic composite pillar array medium is proposed for the ultra high density recording medium. Magnetization reversal process for a single hard/soft magnetic composite pillar in the medium is calculated using the Landau-Lifshitz-Gilbert equation. In the case that the pillar size which corresponds to 1 Tbits/inch2 or higher areal recording density, magnetization vectors for the soft magnetic unit do not form a domain wall nor a vortex. Hence, noise caused by the domain wall or the vortex for the soft magnetic unit is considered to be none. Magnetization reversal of the soft magnetic unit helps the magnetization reversal for the hard magnetic unit, reducing the effective coercivity for the hard magnetic unit greatly. Accordingly saturation recording to the high-Ku hard magnetic material used for perpendicular magnetic recording will be realizable.

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Film Bulk Acoustic wave Resonator (FBAR) is one of the band pass filters employed for high frequency devices. In order to apply FBARs to sensitive mass sensor, quality factor defined by the ratio of the resonance frequency to the full width at half maximum for the frequency characteristics is required to be large. In this study, operating characteristic for the FBAR was analyzed using the commercialized software Ansys (Ansys Inc.) which solves electric field-structure coupled problems using a 3 dimensional finite element method. A change in resonance frequency for the FBAR due to additional weight was confirmed by the simulation, and the FBAR was estimated to show the 10 Hz of the change in the resonance frequency for 2 GHz band operation when 2 pg of additional weight was loaded. Thereby the FBAR was considered to work as a sensitive mass sensor. The electrode materials were found to affect quality factor, and the highest quality factor was also found to be obtained when the electrode is TiN compared with Mo, Ru, Rh and W.

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The [111] oriented Pt/Fe multilayered films were fabricated by electron beam evaporation in an ultra-high vacuum of 10-8 Pa. Keeping the thickness of Fe at 0.2 nm corresponding to one atomic monolayer (ML), several samples with the different Pt layer thickness (npt) from 1 to 8 ML were deposited on the Si-wafer covered with 20 nm thick Au(lll) buffer layer. XRD patterns of the samples with npt G.T. 2 showed well-resolved superlattice peaks. Superlattie periods from XRD and atomic compositions evaluated by RBS spectra almost agree with the designed ones. All the films are ferromagnetic even at room temperature. The magnetization decreases with the increase of np1 at 300 K, suggesting the two dimensional effect for high npt. For the sample with npt =8, the perpendicular magnetic anisotropy was observed at 5 K. Details of the XRD intensity analysis indicate the alloy layer formation.

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A series of five bulk samples of NaxCo2O4-yFy (x = 1.6, y = 0 to 0.20) compounds was successfully synthesized by employing the solution precursor method using CH3COONa, Co(CH3COO)2 and NaF dissolved in aqua regia. The XRD study with the Rietveld analysis revealed that the lattice parameter a slightly decreased with increasing F content y, while the c increased with increasing y. The electrical conductivity (sigma) of the compounds continuously decreased with increasing y. The See beck coefficient (S) once increased from y = 0 to 0.1 0, and decreased above y = 0.15. No improvement in the power factor (S2sigma) was observed in the compositional range of 0 L.T. y L.T. 0.20. The carrier concentration was unchanged over the compositional range of 0 L.T. y L.T. 0.20. A drastic reduction in the thermal conductivity (K) of the compounds was observed by substituting O atoms with F atoms at the anion site in the Na1.6Co2O4 compounds.

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A new zirconosilicate of chemical formula Na2Zr7Si2.5O20·3H2O and its K and Ba ion-exchanged forms are characterized by means of X-ray diffraction, TG-DTA and HRTEM analyses. Preliminary information about space group and unit cell parameters is reported. The structural peculiarities of the studied compound are compared with those of other previously reported zirconium compounds, with similar powder diffraction patterns and unknown crystal structures. An arrangement of the zirconium polyhedra within the crystal structure of these materials is proposed.

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Structure analysis of a slightly partially-dehydrated natural chabazite was carried out using single crystal X-ray diffraction. The presences of the five water sites and four exchangeable-cation sites, found in the fully hydrated sample investigated by our recent study (Nakatsuka et al., 2007), were also confirmed in the present partially dehydrated sample. The final structure refinement converged to R = 0.0280 and Rw = 0.0284 for 926 reflections. The occupancy of the water site located at the center of the 8-ring window in the [412 62 86]-cavity decreases significantly compared with that in the fully hydrated sample.

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Hydroxyapatite (HA) ,Ca10(PO4)6(OH)2, is one of the most biocompatible materials for human bones. HA is promising bone substitute material for clinical application because of clinical stability in vivo. Porous HA scaffolds have attracted a considerable attention for biomedical engineering applications. The objective of this study is to prepare the samples to HA scaffold ceramics for the human cells. Porous HA ceramics was prepared by spark plasma sintering (SPS) at the temperatures from 400°C for 10 min with a heating rate of 25 K min-1• The aramid fiber in ceramics prepared by SPS was burned away during firing at 500°C 1 h in air. The porous HA ceramics prepared by SPS at 400°C had macro pore. Average pore size of the ceramics sintered by SPS method at 400°C was around 15 11m in size. There were almost no pores in the matrix of HA ceramics by SPS method. The measured compressive strength of porous HA scaffold was 40 MPa with a porosity of 30%. These results proved that SPS is a potential method for fabricating porous HA ceramics at the much lower temperature than conventional methods.

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Hydroxyapatite(HA), Ca10(PO4)6(OH)2, is one of the most biocompatible materials with human bones. HA is a promising bone substitute material for clinical application because of clinical stability in vivo. Fine powder of HA were heated at 900°C for 1 h and at 1000°C for 6 h in air. The first objective of this study is to reveal the effect of plastic flow on densification behavior by spark plasma sintering (SPS) from various preheated HA powders. From the isothermal shrinkage behavior, we concluded that the plastic flow in later stage does not depend on the preheating temperature. The second objective of this study is to prepare graduated HA ceramics for artificial bone by SPS. These heating powders (0.25 g) were vertically laminated into the graphite mold and then sintered by SPS at the temperatures from 800°C for 10 min with a heating rate of 25 K min-1• The ceramics prepared by SPS had pores of about 0.1 micro m after heated at 1000°C for 6 h. There were no pores in HA ceramics prepared by SPS before heated at 900°C for 1 h.

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Ettringite crystals grown by combining calcium hydroxide and aluminum sulfate solutions including some admixtures have been observed using the microscope with high magnifications up to 3000 degrees. The nucleation, growth rate and morphology of ettringite were investigated to clear the effect of admixtures on these crystal growth.

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Optimum Fermentation Conditions for Microbial Polyester Synthesized by Delftia Aacidovorans

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Carboxymethyl cellulose (CMC) forms a gel when mixed with acid as a result of replacement of sodium in carboxymethyl group with hydrogen; hydrogen bonds are formed among CMC molecules. CMC gel gets new property by mixing with konjac mannan (KM). KM is a water soluble glucomannan with high molar mass and has high viscosity in low concentration aqueous solution. The molar mass of KM is easily decreased by y-irradiation. Novel CMC-KM mixture gel is made by two processes; (1) mixing CMC with KM solution, (2) immersing CMC-KM mixture paste in hydrochloric acid aqueous solution. Mechanical properties of CMC-KM mixture gel and CMC gel were measured by a material tester. CMC-KM mixture gel was more elastic than CMC gel when high molar mass KM was mixed with CMC. When low molar mass KM was mixed with CMC, properties of CMC-KM mixture gel were similar with those of CMC gel. It was because KM molecules are entangled with CMC molecules when high molar mass KM was used. Interaction of CMC and KM was elucidated by FT-IR.

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Materials having large two-photon absorption cross sections have attracted considerable interest because they offer a wide range of potential applications such as 3D-microfabrication, optical power limiting, optical data storage, two-photon-excited florescence imaging, and two-photon photodynamic therapy. In this study, we measured two-photon absorption cross sections of nanoparticles of phthalocyanine derivatives by the open aperture Z-scan method using a femtosecond Ti: sapphire regenerative amplifier laser. Transparent phthalocyanine nanoparticles dispersed in water was prepared by a method of laser ablation in water. The values of two-photon absorption cross section per molecule of nanoparticles were ea. 48 GM (1 GM = 1x 10-50 cm4 s/photon) at 800 nm for copper phthalocyanine, ca. 65 GM at 820 nm for nickel phthalocyanine nanoparticles, and ea. 121 GM at 820 nm for tetra-t-butyl-substituted copper phthalocyanine. Nanoparticles of the tetra-t-butyl-substituted copper phthalocyanine have a little higher two-photon absorption cross sections than the molecules in tetrahydrofuran.

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Homologous series of 2-oxo-2H-chromen-6-yl 6-alkoxynaphthalene-2-carboxylate (compounds 1) were synthesized and their mesomorphic properties were studied. Compounds 1 showed a nematic (N) phase on cooling process. The isotropic (I)- N transition temperatures of these compounds were estimated to be ea. 140°C on average. We calculated optimized structures of the liquid crystal cores of compounds 1, corresponding benzoate derivatives (compounds 2), and biphenyl-carboxylate derivatives (compounds 3), and found that the N-I transition temperatures seem to have a linear correlation with the core length/width ratio of compounds 1-3. We conclude that the geometrical anisotropy is one of the important factors for the N-I transition temperatures.

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Lithium manganate, LiMn2O4 , applicable as a cathode material for lithium batteries has been synthesized by a redox mechanochemistry route. Gamma-MnO2 shows an excellent reaction ability with LiOH under grinding and the amorphous ground product can be crystallized to LiMn2O4 at 400°C despite the requisition of the partial reduction of MnO2 to MnIIIMnIVO5. Contrary, Mn2O3 shows a poor reactivity. The dissociation of the edge-sharing chains of MnO6-octahedra in gamma- and beta-MnO2 and the increased reactivity of LiOH fused or activated under grinding is the proposed reaction mechanism. The ground products are slightly agglomerated by the moisture evolved from the hydroxide. However, the particle size can be controlled to be 300-500nm after the calcination at 800°C, when the grinding stress is limited not to be high. Unnecessarily high grinding stress induces the strong agglomeration to increase not only the size of agglomerates but the primary particle size. The synthesized LiMn2O4 with the particle size of 370nm and the crystallite of 48nm provides the good cyclic charge- discharge characteristics, while the rechargeability of LiMn2O4 with 500nm and 68nm degrades within 3 cycles.

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Synthesis of lanthanoid cobaltates, LnCoO3 (Ln: La, Pr, Dy), via the mechanochemically prepared complex (oxy-)hydroxides has been studied. The hydroxides are prepared by grinding Co(OH)z or Co3O4 with Ln2O3 (Ln: La, Dy) or Pr6O11 in acetone containing a very small amount of H2O in LnCoO3 • 4H2O composition. The starting hydroxides act as the reactive grinding aids to each other. La2O3 and Co(OH)2 form the complex hydroxide, LaCo(OH)5, that is a sort of inorganic polymers having La-O-Co bond. The hydration affinity of trivalent Co3+ ions is not high enough to form complex hydroxide LaCo(OH)6. Then, the addition of H2O2 to the grinding liquid results in the formation of oxyhydroxide, LaCoO(OH)4. These (oxy-)hydroxides are directly converted to pseudo-tetragonal LaCoO3 at 600°C and rhombohedral LaCoO3 above 800°C without forming any by-product. The redox interaction between Co(OH)2 and Pr6O11, which shows the poor reactivity with Fe2O3, enables the formation of PrCoO(OH)4. Contrary, the reaction with Dy2O3 becomes poor.

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The effects of MOx (M=Al, Ti, Zr) addition on the microstructure, crystallization behavior and optical properties of ZnO-MOx films deposited by sol-gel method were investigated. Zinc acetate dihydrate (Zn(OCOCH3)2 2H2O), ethanolamine and 1-propanol were used as a starting material, stabilizer and solvent, respectively. Aluminum sec-butoxide, titanium i-propoxide and zirconium n-propoxide were used as MOx sources. The surface morphology of ZnO-MOx films fired at 500oC depended on the kind of MOx. In ZnO-AlO1.5 film, the corrugated structure and cracks were observed. In contrast, the surface of ZnO-ZrO2 film was flat with no crack. The grain size of the ZnO-ZrO2 film was large (approximately 80 nm) compared with ZnO-AlO1.5 and ZnO-TiO2 films. The higher crystallinity was obtained in ZnO-ZrO2 ([Zn]/[Zr]=80/20) film compared with other ZnO-MOx films. The addition of AlO1.5 or TiO2 resulted in the suppression of grain growth and crystallization in the films. As a result, only ZnO-ZrO2 ([Zn]/[Zr]=80/20) film exhibited higher transmittance (-90%) in the visible region and higher shielding property (G.T. 90%) in the ultraviolet ray region.

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Diffusion bonding and thermal fracture between Si3N4 ceramic and stainless steel (SUS316) were investigated. Sintered Si3N4 ceramics were fabricated by hot-pressing of a-Si3N4 powder with 5wt% Y2O3 and 5 – 10 wt% A2O3. Bonding between SUS316 plate with 1 mm thick and Si3N4 specimens was carried out at 8 - 24 MPa and at 1000° - 1300°C for 1 h in vacuum. Thermal decomposition of the bonded specimen in air was followed by acoustic emission and high-temperature microscope. Bonding between SUS and Si3N4 was achieved by heating at 1150 and 1200°C in vacuum. When the bonded sample was heated in air, small cracking was formed at 700°C at the interface between SUS and Si3N4, followed by decomposition of the bonded sample at 900°C.

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Ternary compound in the CaO-Al2O3-HfO2 system, 13CaO·6Al2O3·2HfO2 (stated by C13A6Hf2 hereafter), was fabricated by melt process using an arc-imaging furnace. This compound has not been reported ever, based on our knowledge. The new phase has similar XRD patterns to the 13Cao·6Al2O3·2ZrO2 (C13A6Z2) phase in the ternary phase diagram CaO-Al2O3-ZrO2. Though Zirconium and Hafnium generally shows similar properties, the reactivity of these two compounds in the solid phase was totally different. The Zirconium compound (C13A6Z2) was fabricated by both solid state reaction (1200°C, 6h) and the melt process, starting from powder mixture of CaCO3, Al2O3, and ZrO2. On the other hand, the Hafnium compound (C13A6Hf 2) was fabricated only by the melt process from powder mixture of CaCO3, Al2O3, and HfO2. The zirconium pure phase was not fabricated by the solid state reaction; it gave three isolated phases, 12CaO·7Al2O3 (C12A7), CaHfO3, and C13A6Hf2. This difference might be caused by a low diffusion rate of Hf ions in the C12A7 structure.

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Arc in liquid method has been developed as a cost-effective technique to fabricate various kinds of carbon nanomaterials. In liquid nitrogen, especially high-quality multi-wall carbon nanotubes were observed. So, our research aims at creating carbon nanomaterials using contact arc method in liquid nitrogen and in liquid helium. For this research, a special evaporation cryostat, which has moving parts at low temperature part, is prepared. Experiments in liquid nitrogen were carried out at current density 8kA/cm2, 10kA/cm2, 12kA/cm2 and 14kA/cm2. At current density 10 and 12kA/cm2 ample fibrous carbon nanomaterials could be obtained. Then, based on the results of discharged experiments in liquid nitrogen, productive experiments were done in liquid helium. At that time, in discharged experiments, ample carbon clusters could be observed at current density l0kA/cm2 . Using TEM Imaging, it turn out that these clusters were multi-wall carbon nano-tubes. This is the first observation of creating carbon nanotubes in liquid helium.

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Recently, it has been demonstrated that carbon nanomaterials can be synthesized also by arc discharge generated in a liquid medium such as water, liquid nitrogen or liquid helium. Shigematsu et al. have demonstrated that carbon nanomaterials can be produced by de arc discharge in liquid helium. Then, we are working on the clarification of the creation mechanism by analyzing to experiment from both sides of the calculation. And, whether how much time the discharged carbon atom grew up to the size of which extent was examined. The motion of an individual carbon atom was pursued. Carbon velocity after the carbon atoms or the carbon clusters collide is calculated as a perfectly inelastic collision according to the law of conservation of momentum. The process of growing up from the carbon atoms to the carbon clusters that contained a lot of carbon atoms was shown. In addition, it was shown that the number of carbon atoms contained in the cluster for the logarithm at the time of peaks of the number of carbon clusters almost became a linear relationship. The result of this simulation suggests that the growth speed of the carbon clusters in liquid helium be predictable.

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Vanadium and iron doped rutile-type TiO2 were prepared by mechanical milling(MM) at 500 rpm for 15 minutes from the powder mixtures of (x/2)V2O5 (V2O3) + (1-x)TiO2 and (x/2) gamma-Fe2O3 +(1-x)TiO2. XRD results showed the particle diameter d was about 10 nm for host TiO2 powder by MM, and MM for the mixtures of V2O5/TiO2 and gamma-Fe2O3/TiO2 realizes the V and Fe doped TiO2 nano powders. Magnetization measurement showed that M at 300K and 5 kOe was 0.002(x=0.1 )-0.004(x=0.05) micro B/V-ion for Vx Ti1-xO2, 0.024(x=0.05)-0.035(x=0.1) micro B/Fe-ion for FexTi1-xO2. Thus the diluted ferro-magnetic semiconductor powder of (V,Fe)xTi1-xO2 with Tc higher than room temperature were successfully prepared by MM. But all of them were insulators, and not half metallic.

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Li3+xIn1-xMxBr6 (M=Zn, Co, Fe) was synthesized by nano-grinding. No peak of source materials was observed for all the compounds in XRD measurements. With an increase of x for M=Fe compounds, the lattice constants decreased, because the ionic radius of Fe2+ ion are much smaller than that of In3+ ion. In the high temperature phase for Li3+xIn1-xMxBr6 (M=Zn, Co), the conductivity decreased with x. In Zn compound, a new phase transition was observed at about 345 K and the conductivity became higher than that of the medium temperature phase. In Li3+xIn1-xFexBr6, the conductivity of high temperature phase was almost equal to that for Li3InBr6. In 7Li NMR measurement, the spectra in high temperature phase for Li3+xIn1-xFexBr6 was narrowed to be less than 1 kHz. It is indicated that Li+ ion diffuse fast in the crystal and these compounds are good Li ion conductors.

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Magnetite (Fe3O4) thin film was prepared by one-liquid ultrasonic spray plating using an aqueous solution containing FeCl2, NaNO2 and dextran. The starting solution was atomized into mist using an ultrasonic nebulizer and the mist was carried on to a substrate. Using this method, Fe3O4 film was deposited at 90°C; however, NaCl was coexisted with the film and the crystallinity and magnetic property of the film was low. After post deposition annealing at 850oC in N2, NaCl was evaporated, and crystallinity and magnetic property of the film was improved. The mechanism and property of the film was compared with spin spray plating method invented by Abe et al.

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Well dispersion of nano-particles is necessary in order to bring out their unique properties, such as solubility, reactivity, and electromagnetic, optical and mechanical properties. However, it is difficult in general to disperse nano-particles homogeneously in liquid media because they are very prone to coagulate each other. In this study, we have developed and constructed a new apparatus for dispersing particles that basically consists of co-axial rotor and a static vessel to generate a high shear field between them. Coagulated particles are subject to high shear forces which enable to disperse the coagulated particles. In this paper we have firstly designed the dispersing apparatus, and have then carried out the dispersion tests with calcium carbonate particle which has tens nanometer size as a primary particle. The dispersion performance has been evaluated by measuring particle size distribution with taking account of shape of rotors, dimensions of the gap between rotor and vessel, rim speed of the rotor and operating time. It has been found that a smaller gap results in higher dispersing performance since higher velocity gradient is formed in the gap.

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Spherical LiNi0.5Mn1.5O4 precursor powders were synthesized different heating method by internal combustion type spray pyrolysis apparatus using gas burner. After calcinations of as-prepared powders contained Ni at different temperatures from 800 to 1200 oC in air for l0h, LiNi0.5Mn1.5O4 powders were obtained. As-prepared particles have a porous microstructure with an average diameter of about 5 micro.m (spray pyrolysis) and 2 micro m (spray drying) with narrow size distribution. The powder production capacity was 1 kg/h by this equipment. XRD showed that LiNi0.5Mn1.5O4 powders were well crystallized to a spinel structure with Fd3m space group. LiNi0.5Mn1.5O4 powders calcined at 1000 oC shows good cycle performance with initial discharge capacity of 130 mAh/g and 93 % retention after 300 cycles between 3.5 V and 5.0 V. The most of electrochemical properties of LiNi0.5Mn1.5O4 powders that spray drying method offered superior performance to spray pyrolysis method.

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Spherical LiFePO4/C cathode materials were successfully prepared by spray pyrolysis. Particle size, morphology and crystal phase of LiFePO4/C powders were characterized by XRD and SEM. XRD showed that olivine structure was formed by the calcination at 700 oC under Ar-H2 atmosphere. They had spherical morphology with particle size of 1.5 micro m. Electrochemical measurement revealed that the discharge capacity of LiFePO4 was improved by the addition of carbon. The first discharge capacity of LiFePO4/C was about 141 mAh/g and 73 mAh/g at 0.1 C and 5 C respectively.

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Silica/polymethylmethacrylate (PMMA) hybrid thin films were successfully prepared on polybutyleneterephtalate (PBT) substrate by dip-coating using perhydropolysilazane (PHPS) as a silica source. The effect of thermal treatment on conversion from PHPS to Silica was investigated by SEM and FT-IR in detail. Ultraviolet radiation in conversion to silica of thin film was most effective compared with heating in electric furnace. Mechanical properties of silica and silica/PMMA hybrid thin films also were examined by vickers hardness and pencil scratch hardness.

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Photoelectrochemical behavior of the zinc oxide electrode prepared from sintering of zinc oxide powders at the temperature of 900 - 1200°C was investigated for the purpose of application of this electrode to water purification. Photoanodic fading of dyes (Methylene Blue, Crystal Violet, Congo Red) in aqueous solutions on the zinc oxide electrode was examined. In this case, the photoelectrochemical cell consisted of the zinc oxide photoanode in 0.1 M Na2SO4 solution containing 10 micro M dye (volume: 100 ml) and graphite cathode in 10 mM Fe2(SO4)3- 0.1 M Na2SO4 solution (volume: 100 ml) under light irradiation (wavelength: 365 nm, intensity: 30 mW/cm2). Although the electrode sintered at 900°C showed a low photocurrent quantum efficiency, 8 %, mainly due to the many boundaries on the surface, 80 % of the initial concentration of Methylene Blue faded after 6 hours irradiation. The electrode sintered at 1200°C showed 80 % of photocurrent quantum efficiency and caused the fading of Methylene Blue with 86 % of initial concentration after 6 h irradiation. The comparison of responses between photoelectrode and photocatalysis was also checked for the sintered zinc oxide samples.

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Polycrystalline Fe4N thin films were prepared by AP-HCVD from the starting materials of FeCl3 and NH3. The effect of Pt buffer layer on Si(100) substrate was examined. It was clarified that coexistence of the second phases such as Fe3N and alpha-Fe was detected on Pt buffer layer. The sample was deposited on 10 nm-thick Pt buffered Si(100) substrate. It was considered that the introduction of Pt buffer layer affected to the coverage and uniformity of the film.

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Nitrogen doped ZnO is promising for the p-type semiconductor, however, little research work has been done about zinc nitride (Zn3N2) materials. In this study, Zn3N2 films were prepared by Atmospheric Pressure Chemical Vapor Deposition (AP-CVD). XRD patterns showed that Zn3N2 films are polycrystalline if the deposition temperatures were in the range from 500 to 700°C. SEM images exhibited that the Zn3N2 films were consisted of granular grains, and their diameter increased with deposition temperature. We determined that optimal deposition temperature was 600°C since dense microstructure was obtained at this temperature. UV-Vis-NIR measurement showed that optical band gap energy was 1.23eV.

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Large area nano-patterning has been conducted by masked ion implantation with anodic porous alumina. The purpose of this work is to develop a nano-patterning method leading to 3D control for device fabrication. Aluminum anodic oxidation is one of the best controllable self-assembing processes to fabricate large-area pore patterns. An anodic porous alumina was fabricated by two-step anodization process in 0.3 M oxalic acid and phosphoric acid. The two-step anodization process attained periodic porous arrays. The porous a1umina was delaminated from the base aluminum by chemical etching and was mounted onto a crystalline Si02 substrate, removing the residual barrier layer by Ar sputtering. Subsequently, negative Cu ions of 60 keV were irradiated to the substrate. After the irradiation, surface morphology of the Si02 substrate was observed by SEM. The patterned irradiation was successfully conducted with the anodic porous-alumina mask to 1 x 1016 ions/cm2• Beyond this tolerance limit, the pore size decreased with increasing ion fluence, because of ion-induced deformation. In order to reduce the deformation, we also employed Au or carbon coating on the mask surface. The carbon coating significantly improved the radiation resistance of the mask.

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Ge surfaces were irradiated by Ar+ ions of 600 eV with and without a simultaneous Ge supply at various temperatures up to 200°C. The surfaces ion-irradiated without a Ge supply were characterized by conical protrusions, independent of the fabrication temperature. By contrast, densely distributed cones, nanobelts and nanowalls were formed on the surfaces ion-irradiated with a simultaneous Ge supply even at room temperature. Because the formation of those nanobelts and nanowalls was specific to sputtering with a Ge supply and enhanced by sample heating, it was concluded that the surface diffusion of the supplied Ge atoms played an essential role in their formation. Thus, it was believed that the ion irradiation method would open up a new route to fabricate low-dimensional nanostructures of semiconductors at low temperatures.

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Cluster ion beam processes can produce higher rate sputtering with lower damage compared with monomer ion beam processes. In particular, it is expected that extreme high-rate sputtering can be obtained using reactive cluster ion beams. Several kinds of hydrofluorocarbon (HFC) (CF4, CHF3, and CH2F2) and Cl2 gas clusters were generated, and their cluster size distributions were measured using the time-of-flight (TOF) method. Si substrates were irradiated with the reactive cluster ions at acceleration energies in the range of 5-80 keV. The sputtering yield increased with acceleration energy and was about 1000 times higher than that of Ar monomer ions for comparable conditions. Despite the very high sputtering yields, a Si surface irradiated by reactive cluster was smoothed. This high-speed processing with reactive cluster ion beam can be applied to fabricate nanodevices.

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