Thin Cu films with different thickness and microstructure were prepared using evaporation with a quartz substrate, followed by microwave irradiation in air (frequency of microwave:2.45 GHz, incident flux of microwave:563 W, irradiation time: 600 s). Microwave heating of thin Cu film is quite anomalous. The abrupt temperature rise and drop occur at early stage of microwave irradiation, then continuous temperature rise appears. The temperature change is caused by various combinations of the change in the rate of temperature rise (delta T) due to the ratio of a thickness to resistivity of thin Cu film, the increases in delta T due to Cu-oxide and resistivity rise at elevated temperature, and the decreases in delta T due to Cu particle growth during microwave irradiation and heat radiation from the surface of thin Cu film.

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The interface potential of microparticles in aqueous solution is an important factor for scale formation in a water piping. For application to scale prevention process, the influence of alternating electromagnetic field on the interface potentials of CaCO3 particles in the solution was investigated. Using a suspension of CaCO3 particles dispersed in an electrolytic solution, we measured zeta potential changes of the particles by imposition of weak alternating electromagnetic field at different frequency. Consequently, we found that the specific frequency treatment changes the interface potential of particles drastically with an inversion of its sign. It is considered to be due to the specific adsorption of anions in the solution on the particles interface by the effect of induced electric field.

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Morphological effect of a susceptor on Joule heat by induction heating was investigated. Numerical computation of Joule heat was based on mutual inductance model suggested by Tarapore and Evans. The calculated results were compared with experimental results. In experiment, susceptors were made of stainless steel or graphite with two shapes: cylinder-type (Phi 40, or 50 mm X 80 mm) and tube-type (Phi 50 x 80 mm). These were put on the center of a coil and then, their Joule heats were experimentally measured by a specific apparatus using water flow rate and temperature difference. Magnetic field is canceled out by eddy current in cylindrical stainless steel, whereas penetrated to the inside of tubular stainless steel. The calculated values corresponded well to the observed values, within error range of less than 5%. When maximum current of 1A was imposed into the coil, the cylindrical susceptor (Phi 40 mm x 80 mm, stainless steel) placed at middle of the coil generated Joule heat of 9.1 x 10^-3 W/A2 , higher than that of 5.4 x 10^-3 at both ends of the coil. The graphite also showed the same tendency as stainless steel. With a decrease in thickness of the tubular susceptor, heat generation increased because inductive reactance effect deceased and current density became much higher. The tubular stainless steel (Phi 50 mm x 80 mm, t/delta = 0.1) had extremely high heat generation (5.3 x 10^-2 W/A2), matching up to the experimental results. As a result, tubular susceptor heating may compensate various industrial melting systems for large energy consumption, as well as induction furnace.

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Sodium borosilicate glasses were produced from coal fly ash and their properties were investigated. Fly ash could be vitrified completely by induction heating at 1500°C for 30 min with Na2O or B2O3 additions of more than 10 wt.%. The induction furnace incorporated a new method, namely, induction susceptor heating and employed a cylindrical graphite rod as the susceptor that could efficiently capture the electromagnetic energy. The alkali borosilicate glasses produced had Vickers microhardness of 3000-4000 MPa, bending strength of 30-40 MPa and indentation fracture toughness of 0.7-1.1 MPa·m^1/2. With suitable Na2O and B2O3 addition, their melting points decreased down from 1500°C to less than 1200°C. Finally, their chemical resistances against acid leaching indicated that heavy metals were immobilized well under environmental regulation. Therefore, alkali borosilicate fly ash glasses should be recycled as materials with good chemical resistance.

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This paper describes effects of temperature and applied strain on thermomechanical properties of Ni-free Ti-Mo-Sn alloys. The materials used are Ti-6Mo-4Sn, Ti-5Mo-5Sn, Ti-5Mo-4.6Sn and Ti-4.4Mo-5.6Sn (mol%). Loading-unloading tensile tests were carried out under the applied strain of 3% at temperatures between 183K and 323K. Additionally, loading-unloading tensile tests were carried out under the applied strains ranging from 1% to 6% at 183K. Young's modulus decreases with increasing temperature. Ti-5Mo-4.6Sn shows the smallest young's modulus at temperature above approximately 215K. There is a decrease in the critical stress for inducing martensites with increasing temperature. The largest critical stress for inducing martensites is found in Ti-6Mo-4Sn. Also, the critical stress for inducing martensites increases with increasing Mo content, in contrast, decreases with increasing Sn content. There is a decrease in the superelastic recovery strain with increasing temperature. Ti-5Mo-5Sn showed the largest superelastic recovery strain of nearly 2% under the applied strain of 4% at 183K.

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This paper describes thermomechanical behavior and electric characteristic of Ti-Ni-Cu shape memory alloy. The Materials used in this study are Ti-41.7Ni-8.5Cu (mol%) and Ti-42.6Ni-7Cu (mol%) alloys. Cold working ratio of the Ti-41.7Ni-8.5Cu (mol%) alloy wire was varied from 10% to 40%. Heating-cooling tests under the pre-strain was ranged from 1% to 3% were carried out using the Ti-41.7Ni-8.5Cu (mol%) alloy wire at the isothermal temperature of 273K, for investigating the thermomechanical behavior of Ti-Ni-Cu alloy. Heating-cooling tests under the pre-strain was varied from 0% to 3% were also carried out using the Ti-41.7Ni-8.5Cu (mol%) alloy wire at room temperature, for examining electric characteristic of Ti-Ni-Cu alloy. The large pre-strain and high cold working ratio have efficacy for obtaining large recovery stress. An increase in the pre-strain has slightly increased the transformation temperature hysteresis (Af' -Ms'). Also, the temperature responsive property has become lower with an increase in the pre-strain and cold working ratio. On the other hand, an increase in the pre-strain facilitates control of the SMA actuator because it decreases the electric resistivity hysteresis.

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This paper describes effects of Mo and Nb contents on mechanical properties of Ni-free Ti-Nb-Mo-Al alloys. The materials are Ti-8Nb-4Mo-3Al, Ti-8Nb-(5-6)Mo-5Al and Ti-(10-12)Nb-4Mo-5Al (mol%). Loading-unloading tensile tests were carried out at 173K, 296K and 413K. Young's modulus decreases with increasing Mo and Nb contents, and the Ti-8Nb-6Mo-5Al and Ti-12Nb-4Mo-5Al alloys show low Young's modulus. Also, there is scarcely an effect of temperature on Young' modulus. The elastic strain increases with increasing Mo and Nb contents. The Ti-8Nb-5Mo-Al and Ti-12Nb-4Mo-5Al alloys show the large superelastic recovery strain at 173K and 296K. However, there is scarcely the superelastic recovery strain at 413K. The large total recovery strain is seen in the Ti-8Nb-(5-6)Mo-5Al and Ti-12Nb-4Mo-5Al alloys at 173K and 296K.

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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 bias force such as coil spring and constant load is required to deform the shape memory alloy in martensitic phase. In this work, the effect of a bias load on the positioning characteristics by resistance feedback control is investigated. The produced actuator is heated by electric current and it can control the position using a constant mass and a bias spring as a bias load. The Ti-Ni-Cu alloy wire is used as an actuator element. The positioning characteristics such as settling velocity, positional error, and position accuracy are discussed in relation to the bias load. The results show that the settling velocity at heating decreases and the settling velocity at cooling increases with increasing in the bias load. Furthermore, the positional error at heating is very small and the positioning control against the desired position during heating can be controlled accurately.

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Superelastic properties of Ni-free Ti-Mo-Sn shape memory alloys (SMAs) were investigated using tensile testing. The solution-treated Ti-Mo-Sn alloys showed a recoverable strain of over 3%, while the alloy heat treated at around 923 K exhibited a high tensile strength of over 1000 MPa. Based of those results, a new type of guidewire with functionally graded properties from the tip to the end was developed using Ti-Mo-Sn SMA core wire. This guidewire is expected to show excellent pushability and torquability superior to those of stainless steel and Ti-Ni guidewires. In addition, Ti-Mo-Sn tubes, which are expected to be used for metallic catheters, were fabricated. The superelastic properties of those tubes are also reported.

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FEM analysis results for coil spring specimens of Ti-Ni shape memory alloys were compared with experimental results in the superelastic regime. The input data for FEM analyses were obtained from wire specimens of the same material as that of coil spring specimens. The calculated results did not agree with experimental results. Two possible causes were pointed out on the disagreement between calculated and experimental results. One is the insufficient treatment in the constitutive relations under multiaxial stress states. The other is the discrepancy in the work rates between coil spring specimens and wire specimens. Some examinations were performed on these points.

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Cement manufacturers today use various waste materials and by-products as raw materials or fuels in cement manufacturing. Waste materials and by-products, however, often have certain chemical properties that differ from conventional raw materials and fuels. Thus, we have researched the overall influence of several minor elements in clinker on the properties of clinker and cement, and we suggest practical measures for Japanese cement manufacturers to take against the unfavorable influence of each minor element. This article introduces our approach and provides representative results and an example of commercialization. We also discuss further challenges in this field as it moves toward rational cement manufacturing.

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

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In order to enable concrete production plants to reduce their manufacturing processes and costs, we prepared concrete with finely ground Ca(OH)2, which improves the setting of concrete. We steam-cured concrete, and experimentally evaluated the effects of the added Ca(OH)2 and the curing conditions on the concrete's strength development. The results show that adding finely ground Ca(OH)2 enhances the early strength of concrete. At a maximum temperature of 80°C the concrete exhibited the same level of strength as concrete that had been cured for 24 hours before removing the mold, even though a shorter curing time was used.

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The structure and electrochemical properties of Li[Ni1/2-x/2Mn1/2-x/2Lix]O2 (0 less than x less than 1/5) with a layered rock-salt type structure have been investigated. The samples were prepared by the co-precipitation of Ni-Mn double hydroxides and the subsequent solid state reaction with LiOH. The electron diffraction indicates a [root 3 x root 3] R30 °type ordering in the transition metal layers and the order parameters increase with increasing x. Rietveld refinements of X-ray diffraction patterns for Li[Ni1/2-x/2Mn1/2-x/2Lix]O2 indicate some cationic disorders of Li+ and Ni2+ between 3a and 3b-sites. The fraction of extra- Ni2+ in the Li layers is reduced with increasing the Li composition. The electrochemical properties were discussed based on the crystal structure and the morphology.

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Configurations of a yoke and a permanent magnet was optimized in a down-sized micro-strip isolator which was achieved by utilizing a yttrium iron garnet ferrite single crystal with a very small full-width at half-maximum of ferromagnetic resonance curve. Combination of a 0.1-mm-thick iron yoke and a 0.1-mm-thick SmCo type permanent magnet could produce magnetic bias field of 500 Oe which enables the isolator to operate at 1.85 GHz in above resonance mode. The size of the designed isolator was 4x3.5x1 mm which was 1/90 of the conventional micro-strip isolator which operates in below resonance mode. Superior non-reciprocal transmission characteristics of the isolator were also proven by high frequency electromagnetic simulation based on a 3D finite-element-method.

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The surface treatment, which improves outgassing property for the titanium materials, was examined in this paper. A chemical polishing using a nitric acid solution was found to be the most suitable for the titanium materials, because the polished titanium has a surface roughness of 1.80 nm in a microscopic range of 1 micro m and thin oxide surface layer thickness of 7 nm, and the polishing solution has stability and workability. And the surface processing for the titanium was developed by the combination of the chemical polishing and the precision cleaning. The chemically polished pure titanium of JIS grade 2 showed excellent outgassing rate below 10^-12 Pa m s·1 after baking process, which is two orders of magnitude smaller than that for standard vacuum materials under the same baking condition. Outgassing rates of the titanium is about 1/6 of that for a stainless steel without baking process.

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The deposition of tungsten oxide thin films on the polymer sheets was performed by reactive r.f. sputtering method. It was found that the tungsten oxide thin film changes the color from transparency to deep blue within few minutes to expose 0.1 % hydrogen, such as to be recognized the change by viewing with the naked eye. The tungsten oxide thin films is useful as convenient sheet-type hydrogen sensors for the utilization of hydrogen in fuel cell as a clean energy source.

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The conversion efficiency of light-electricity of the solar battery decreases when the temperature rises. To prevent this rise in temperature of the solar battery, wavelength selective transmission thin films that cut the 1000 nm-1400 nm wavelength range were developed. In this research, a solar battery provided with wavelength selective transmission thin films was made for trial purposes, and was compared to a past solar battery. When light was irradiated on the solar battery by using a source of light with heat rays, the rise of the surface temperature of the solar battery made for trial purposes was suppressed. The conversion efficiency of the solar battery was studied by using artificial sunlight, too. From the results, it was found that the new prototype of the solar battery is better than the old one. Therefore, it was understood that the wavelength selective transmission thin films were effective for improving the efficiency of the solar battery through suppressing the temperature as described above.

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In recent years, with the development of optical communication and thin film process technology, the application of optical multilayer films has attracted considerable interest. In this research, the aim is to prepare reflection-reducing thin films which can be applied to solar cells and raise their performance. The optical films were designed using Essential Macleod simulation software, and then were fabricated by radio frequency (RF) sputtering equipment. Two kinds of targets were set, and prescribed flow rates of oxygen and argon gas were introduced into the chamber. The multilayer films were deposited on two sides and on one side of quartz glass substrates while controlling the materials and thickness under the simulation designs. The optical characteristics of the designed and experimented multilayer films were measured by a spectrophotometer. From the results of transmittance, it was found that the aimed multilayer films which have a high transmittance in the visible spectrum were able to be prepared successfully. If necessary the reflection-reducing wavelength range can be controlled by changing the accumulated sequence, materials, number of layers and thickness of each layer.

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Solid-state dye-sensitized solar cells were fabricated with solid polymer electrolyte consisting of I-/I3- redox couple supporting electrolyte and a hyper-branched graft copolymers of poly(methyl methacrylate-co-chloromethlystyrene )-g-poly[(oxy-ethylene)9 methacrylate] (PMMA-g-POEM9) synthesized by atom transfer radical polymerization (ATRP). The photoelectrochemical performances shows the low efficiency for energy conversion, in comparison to the cells with liquid electrolytes, due to the reduced mobility of I-/I3- in polymer electrolyte and the poor electric contact between polyelectrolyte and porous thin film electrode. For the improvement of the performance, the use of polyethyleneglycole (PEG) solution and heating treatments of solar cells were examined. On the Dye-sensitized solar cells (DSSCs) improved these methods, the short circuit current density and the open circuit voltage obtained for an incident light intensity of 110 mW cm^·2 were uplifted to 0.571 mA cm^·2 and 0.599 V, respectively. This corresponds to an overall efficiency to electric energy conversion efficiency and fill factor of 0.228 % and 0. 734, respectively.

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The preparation of ferric oxide in montmorillonite (denoted as MT) was conducted with two kinds of methods: one is that a trinuclear iron complex (precursor) is loaded into the clay, followed by its calcination (denoted as Fe2O3/MT), and the other is the hydrolysis of ferric ion into hydrous ferric oxide (i.e., an amorphous ferric oxide) (denoted as HFO/MT). Both of the samples were prepared with a low loading of ferric oxide into the supporter. The polymorph of 5 wt. % Fe2O3/MT was assigned to the amorphous phase, similar to that of 5 wt. % HFO/MT; moreover, the specific surface areas of ferric oxide were almost constant in each case. When those photocatalysts of ferric oxide were applied to the photo-Kolbe reaction (i.e., methane formation from acetic acid), it was noted that the photocatalytic activity of amorphous ferric oxide for the methane formation is independent of the preparation procedures of the photocatalyst part.

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The effect of blending LiMn2O4 nano particles with different composition was investigated to improve electrical properties of lithium secondary battery. As-prepared powders were synthesized by ultrasonic spray pyrolysis using metal nitrate solution. XRD showed that blended LiMn2O4 powders were well crystallized to a spinel structure with Fd3m space group. The blended particles have non-spherical morphology with an average diameter of about 0.5 micro m in a diameter and a narrow size distribution. The charge/discharge capacity of blended LiMn2O4 exhibited stable cycle performance over 100 mAh/g at 0.5 mA/cm2 between 3.5 and 4.4 V. The cycle performances of blended LiMn2O4 maintained about 90 mAh/g after 100th cycle at 80°C. Reduced Jahn-Teller distortion of lithium manganese by blending LiMn2O4 was the causes for enhanced cycle performance of LiMn2O4.

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Ti-Ni shape memory alloy (SMA) is a functional material applied to various fields. This alloy has been applied in the thermal engine, actuator for micro robot, fishing line and dental corrective devices. In general, shape memory treatments were carried out by electric furnace. If using the current heat treatment with a view to improving a shape memory heat treatment, SMA has a much boarder range of application. This study explored the effects of the electric current heat treatment on the shape memory behavior. Ti-Ni thin wires with diameters of0.3mm were made by melting ingot followed by drawing the wires. The composition of this wire was Ti-50.2at%Ni. These wires were electric current heat treated at 8V 0.7A and 16V 1.7A in the range of 5 minutes, 15 minutes and 30 minutes respectively. The transformation temperatures were measured by a Differential Scanning Calorimeter (DSC) during cooling and heating. Mechanical properties were measured by a tensile machine. From DSC measurement, all specimens were appeared shape memory effect. From stress - strain measurement, the best current heat treatment condition is 8V-30 minutes.

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A prototype of oxide thermoelectric module consisting of p-NaCo2O4/n-ZnO sintered materials was successfully fabricated for electrical power generation by applying a diffusion welding technique without filler metals. The power generation characteristics examined in the high temperature region revealed that the diffusion welding technique under a condition of 16 MPa at 1023 K in Ar was suitable to joint the sintered oxide materials with silver conducting strips. Twelve pairs of p- and n-oxides were connected in series with a planar arrangement in a square area of 30x30 mm2. A maximum power output of 58 mW was obtained at a temperature condition of TH/TL = 839/377 K, and no deterioration in power output was observed even after twenty times of heat cycling.

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In this experiment, polyurethane was liquefied by high-pressure steam treatment without using acidic or alkaline catalysts and solvent. The results of the viscosity and GPC (Gel Permeation Chromatography) showed that part of the molecular weight of the liquefied urethane attained either diamine level or prepolymer level. Furthermore, variation in the hydroxyl number, the amine value and FT-IR spectroscopy with high-pressure steam treatment time showed that urea and urethane bonds in the polyurethane were specifically broken. In addition, the decomposed liquid could readily react with cross-linking agents, and mechanical properties of recycled polyurethane such as shore hardness, tensile strength, 300% modulus, tearing strength and compression set were almost equal to the original polyurethane. This investigation therefore shows that urethane recycling method we can be established easily. More importantly this recycling method does not adversely affect the environment.

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Zeolite NaA membranes were prepared on the surfaces of a-alumina cylindrical supports using the hydrothermal synthesis. Regardless of the porosity size of the a-alumina support, the zeolite membranes consisted of three layers. Compared with the previous membrane, which was prepared on mullite support, the zeolite crystals layer was thicker and the intermediate layer was thinner. Grain boundary clearance (non-zeolite pore) size of the membrane was evaluated by permporometry. Average Kelvin diameters, which were defined as the diameters at nitrogen permeance of 50 %, were at ca. 1.8 nm Kelvin diameters regardless of the porosity size of the support. The maximum value of the pore size distribution of the zeolite membranes was at ca. 1.6 nm Kelvin diameters regardless of the porosity size of the support, and only its value increased with the increase in the porosity size of the support. The membrane performance in pervaporation (PV) increased with the increase in the porosity size of the support. For industrial application of the membranes, the support of 37.6 % porosity was adopted from economic standpoint. The membrane was ca. 1.2 times as high performance as the previous membrane. A high separation mechanism of PV and vapor permeation (VP) based on the capillary condensation (or pore-filling) of water in the non-zeolite pores and the blocking of other molecules from entering the pores was proposed.

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Novel elastic gel was obtained by immersing paste of sodium carboxymethylcellulose (CMC) in acid solution. The paste was prepared by mixing CMC and water at the concentration of 20%. Water absorption and mechanical strength of the resultant gel were evaluated after removing uncrosslinked CMC and acid. Combination of radiation crosslinking and the immersion in acid resulted precise molding and dimension stability of the gel. Maximum mechanical strength of the gel at 50% compression increased with acid concentration for the unirradiated and the irradiated samples at 5-20kGy. The gel prepared by irradiation at 5-10kGy and the immersion did not cause rupture after 50% compression and was more than 100 times stronger than the radiation-crosslinked gel. The reason of the mechanical strength was attributed to crosslinks formed by the acid treatment The crosslinks by the irradiation had been referred to chemical bonds, whereas, those by acids were caused by hydrogen bonds, which was elucidated by FT-IR, ICP and TG-DTA measurements. Sodium in the carboxymethyl groups is replaced by hydrogen in the acid solution. The hydrogen bonds induced the decrease of CMC solubility in water and formed the elastic gel.

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Spherical metal (Fe, Al or Mg) doped Li[Ni1/3Mn1/3Co1/3]O2 precursor powders were synthesized by ultrasonic spray pyrolysis using aqueous solution of metal nitrate. XRD, SEM and BET analysis were used for determination of the composition, morphology, particle size and surface area. SEM observation showed that the size of as-prepared particles were about 0.9 micro m with narrow size distribution. The crystal phase of metal (Fe, Al or Mg) doped Li[Ni1/3Mn1/3Co1/3]O2 was resulted in layered rock salt structure with R3m space group after calcinations at 1023 K, 10 hrs. No impurity-related peaks are observed from the XRD pattern with various doping metals. Mg and Al doped Li(Ni1/3Co1/3Mn1/3)O2 showed a very good cycling stability. The Mg substitution for Ni led to the most excellent results. On the other hand, the capacity fading on cycling was observed for Fe(5%, substitution for Mn) and Mg(30%, substitution for Co and Mn) doped Li (Ni1/3Co1/3Mn1/3)O2.

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In this work, the TiO2 films were deposited on glass substrates using a paste mixture by spin coating method and heat treatment at temperature of 400°C and 500°C for 3hrs, respectively. The crystal structure, optical property, composition and surface morphology of the films thus prepared were characterized by x-ray diffractometry (XRD), UV-Vis spectra, X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). In addition, the hydrophilicity of the films was evaluated by optical contact angle measurements (OCA). The XRD results indicate that the sample post-annealed at 500°C has higher quality of crystallization. The UV-Vis spectrum shows that absorptions of the three samples in visible light region are almost the same. The band gaps of samples without post-anneal, post-annealed at 400°C and 500°C calculated from UV-Vis spectra is 3.1eV, 3.17eV and 3.19eV, respectively. The surface of sample annealed at 500°C is smoothed, post-anneal also increases the size of particles and changes the shape of particles. Then, the sample post-annealed at 500°C has better hydrophilicity than the other samples.

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In order to reduce the atmospheric concentration of carbon dioxide (CO2), a greenhouse effect gas, the collection and fixation of the emitted gas must be carried out. In the experiment iron carbonation reaction was examined. Iron powder absorbed CO2 and converted into carbonate in water at room temperature. One gram of iron powder can absorb 450 ml of CO2. The important element for successfully and efficiently absorbing CO2 is maintaining the anaerobic conditions. The rate depended on the partial pressure of CO2 when a sufficient amount of iron was provided. In this reaction, besides carbonate, hydrogen gas (H2) with a volume equal to that of absorbed CO2 was produced by the decomposition of water. The process can reduce CO2 and supply H2 simultaneously at low cost especially when waste iron is effectively used.

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Nonlinear optical borate crystal has been attracted much attention as wavelength conversion device with development of ultra violet (UV) all solid-state laser systems. Li2B4O7 crystal is one of promising nonlinear optical crystals in UV region as well as piezoelectric substrate for SAW and BAW devices. In this paper, we have examined scatter center with submicron size, which is most effective defects, leading to the degradation of nonlinear optical devices in UV region. The scatter center is a void and the size distribution of scatter centers is revealed by the transparency measurement in UV region. From these experimental results, scatter free Li2B4O7 single crystals showing high transparency in UV region have been successfully grown by Czochralski (CZ) method with dry air flow.

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Titanium silicalite-1 (TS-1) tubular membrane was used as a catalytic active membrane reactor in the oxidation of iso-propanol with hydrogen peroxide. The TS-1 membrane prepared at 150°C showed the highest catalytic activity with the conversions above 90%. The kinetic parameters of the reaction were calculated and a simple column mathematical model was used to describe the catalytic activity of the membrane reactor.

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Self-supported zinc carbonate hydroxide (Zn5(CO3)2(OH)6) film was fabricated using an air-liquid interface. ZnO film was firstly prepared from an aqueous solution containing zinc nitrate hexahydrate and ethylenediamine at 60 oC for 6 h and 25 oC for 42 h. ZnO was dissolved gradually as the solution temperature decreased. Zn5(CO3)2(OH)6 was then crystallized by ion supply from the solution to form a film at the air-liquid interface for 1 month. The resultant film was a single phase of Zn5(CO3)2(OH)6 and an assembly of thin sheets. The film had different morphologies on the air side and on the liquid side, reflecting the direction of crystal growth of thin sheets. The air-liquid interface provided a novel reaction field for crystal growth.

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Nano meter-sized SiO2 lines have been formed on silicon (Si) surface by using AFM tip-induced anodization. A thin water film between the tip and the Si surface worked as a highly resistive electrolyte in a wet air atmosphere. The applied bias voltage dependence of widths and heights of the oxide lines was investigated. It was revealed that the Si was oxidized at very low bias, such as 2.2 V. The thinnest line width of 100 nm has been achieved. The carrier type and concentration were also important factors on the size control in the anodic oxidation.

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Lanthanum hexaboride (LaB6) single crystals have been used as thermionic source in high resolution electron microscopes for over 50 years. LaB6 nanowires have great potential to be used as field emission electron point source, which offers larger brightness than thermionic source. We have developed a chemical vapor deposition process to synthesize LaB6 nanowires on Si substrate with a yield rate of 0.5 mg/cm2. Epitaxial growth of vertically aligned LaB6 nanowires has also been successfully realized on LaB6 films. By using an electrostatic attaching method followed by focused ion beam welding, we successfully fabricated single LaB6 nanowire field emitters. Field emission I-V curve measurement has been carried using a home-built 2010F HRTEM field emission in-situ holder. Extrapolated data shows that the nanowire field emitter has a low work function value of 2.3 e V and it generates an emission current over 20 micro A and an emission current density in the order of 10^8 A/cm2 at a low extraction voltage below 300V.

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Ag loaded TiO2 aerogels were synthesized by sol-gel and supercritical drying methods. Anatase-TiO2 phase was obtained after post-annealed at 400°C for 4 hrs in air. AFM image revealed that post-annealed sample at 400°C consisted by the rod-like particles with several hundreds nanometer. The colorless sample changed to dark brown after the UV irradiation, and returned to the initial state after the white light irradiation. The absorption spectra exhibited a little red shift after the UV irradiation, which may attribute to the appearance of metal Ag particles in TiO2 matrix. Due to the poor crystal quality and no aggregation for Ag+ during post-annealed process, no big wavelength tuning had happened as speculated based on particle size and surrounding media.

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This paper presents the reproducible non-lithographic method for the microfabrication of a metal oxide film through a chemical deposition route. This method consists of three processes. First, by using a fluoroalkylsilane molecule, i.e., heptadecafluoro-1,1,2,2-tetrahydrodecyl trimethoxysilane (FAS; CF3[CF2]7CH2CH2Si[OCH3]3), a SiO2/Si surface was densely covered with a self-assembled monolayer (SAM) of FAS. In order to make a chemical template, the FAS-covered surface was irradiated with a vacuum ultraviolet light (VUV) with a wavelength of 172 nm for 30 min at a reduced pressure of 10 Pa through a photomask. As a result, we obtained a FAS-SAM template with alternating hydrophobic trifluorocarbon (CF3) and hydrophilic SiO2 monolayer (SML) regions. Next, a film of metal oxide, i.e tin oxide, was deposited on the substrate with the FAS-SAM template. Tin oxide film grew on both irradiated and unirradiated regions, but the physisorptions deposited even on the undesired region were perfectly eliminated from its surface by our developed ‘solution lithography’, resulting a highly resolved micropattern of tin oxide film. Its pattern-resolution did not change even after the heat treatment at 600°C which is sufficient to crystallize the as-deposited film.

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We synthesized cyclic phenylazomethines via dehydration of aromatic amines with aromatic ketones in the presence of titanium tetrachloride as a Lewis acid. Stepwise synthesis of a cyclic tetramer of phenylazomethine was also successful. Protonation behavior of the cyclic tetramer was investigated using UV-vis spectral measurements. The cyclic tetramer itself is not redox-active, but a reversible redox wave appeared in cyclic voltammograms when protonated in the presence oftrifluoroacetic acid. We revealed that the redox potential is controlled by the concentration of the acid.

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We synthesized a linear structure of organic-metallic hybrid polymers by complexation of iron(II) acetate with novel bis-terpyridines bearing alkoxy chains as an electro-releasing group. Introduction of alkoxy groups to bis-terpyridines was achieved during a reaction of bromo-substituted bis-terpyridines with sodium alkoxide in DMF. When we use alkane-diol as a starting material, a unique bis-terpyridine with a cyclic structure obtained via intramolecular cyclization. Formation of the corresponding hybrid polymers based on complexation of the organic module with iron(II) ions was confirmed as increase of a MLCT absorption in the UV-vis spectral measurements. We found that a blue shift of the MLCT absorption is caused by introduction of electro-releasing groups to the organic modules.

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Functionalization of silicon tip was carried out by photochemical/thermal hydrosilylation with an alkene-terminated sugar derivative. Si-C bond formation was suitable for preparation of monolayer on silicon surface. The tip was heated in a toluene solution of a sugar derivative with a special flask for hydrosilylation of small materials. With the functionalized tip, patterned surface of a silicon substrate was scanned.

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The conjugates of polyester and glycopolymer were synthesized using poly(lactide) macromer. The macromer of poly(lactide) was synthesized by the ring opening polymerization with hydroxyethyl methacrylate, and the macromer was co-polymerized with alpha-glucosyloxyethyl methacrylate (GEMA) with radical initiator. The physical properties of poly(GEMA)-poly(lactide) was dependent on the monomer ratio in the polymer. The conjugate showed the specific affinities to the alpha-glucose recognition lectin.

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The cell spheroid having high differentiation ability is biologically interesting as a promising technology for tissue engineering. In the present study, we've succeeded in controlling the size of cell spheroids which were two-dimensionally aligned on the micropatterned substrate. To use the spheroids for tissue engineering as an implantable construct, we designed the biocompatible hydrogels with photo-crosslinkable polymer, based on end-acrylated multi-armed poly(ethylene glycol). These gels' storage elastic modulus G' was determined from rheologycal test. As a result, the gels' modulus covered between 100 and 2500Pa by changing the different concentrations and types of macromers. The permeability of these hydrogels was determined using the two-chamber cells. In use of sodium benzoate as probe molecules, the probe passed through all the gels, while no clear effect in the different types of monomers was observed. After photoencapsulation of the chondrocyte spheroids, the multi-array formation of spheroids were maintained in the hydrogel. Biochemical analysis demonstrated that aggrecan increased for 1 week on the hydroge1s and the viability of the cell. Therefore, noble cell spheroid sheet was established using PEG hydrogel. These findings suggest the gel may have high utility as an implant multi-arrayed cell spheroids.

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Phenylboronic acid in water exists as an equilibrium mixture of the nonionic trigonal boronic form and the ionic tetrahedral monoboronate form. It is known that the tetrahedral-formed phenylboronate can form significantly stable covalent bonds with polyol compounds including glucose in aqueous solution. Therefore, the binding/dissociation equilibrium between boronic acids and sugar molecules can be controlled with pH change. However, there has been no report on controlling this equilibrium by the external stimulus such as light and magnetic field. Thus, we tried to create a novel photo-swiching compound which can control the binding/dissociation with sugars by photoirradiation as an external stimulus at a constant pH condition. In our strategy, an azobenzene moiety which gives the geometrical change of photoisomerization (cis-trans isomerization) is employed as a photo-switching moiety, which leads the change of the acidity of boronic acid with the electronic and steric effects. Therefore, we synthesized o-, m-, p- azophenylboronic acids (APB) which have phenylboronic acid and azo groups. It was confirmed that the isomerization of synthesized compounds was certainly induced, which was measured by UV-vis and 1H/13C NMR. Furthermore, it was confirmed using 11B NMR measurement that the binding/dissociation ratio to fructose was changed before and after photoirradiation. In this study, it was proved that newly synthesized boronic acid derivatives can control the binding/dissociation to sugar by photo-stimulation at a constant pH condition. In near future, this new sugar-recognition system is expected to be utilized in medical field as a biosensor and so on.

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Quartz crystal microbalances (QCM) loaded with poly(N-isopropylacrylamide; NIPA) or poly(N-isopropylacrylamide-acrylic acid, sodium salt; NIPA-SA) micro-hydrogels were prepared. Oscillation frequency of the QCMs for the series of solutions was measured as a function of solution temperature and concentration of additive adsorbates (acrylic acid; AAc and Cu2+ ion) in the solutions. The QCM loaded with the gels showed the characteristic oscillation behavior responding to the phase behavior of gels. Drastic shift of the oscillation frequency was observed at the phase transition temperature, TP, of the gels. The critical temperature TP at which the drastic change in the oscillation frequency shift appeared decreased by the addition of adsorbates. The change in hydrophobic/hydrophilic balance of the gels due to the adsorption of additives onto the gel resulted in the shift of the critical temperature. The results obtained in this study demonstrated that stimuli-sensitive polymer hydrogel coupled with QCM is a promising device for molecular sensing through the adsorption induced phase change of the gel.

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We have measured volume change of microcapsules composed of dioctylphthalate inner core and polyethyleneglycol-grafted poly(ureaurethane) (PUU) wall membrane induced by solvent exchange in dispersing medium from water to ethanol. The time course of the process consisted of a lag phase, a swelling phase and a shrinking phase. The temperature dependence of the duration of the lag phase t1 was roughly described by the Arrhenius plot, and the slope for the logarithm of the time constant vs. the reciprocal of the absolute temperature was coincident with that of the viscosity coefficient of ethanol, suggesting that the permeation rate of ethanol into the core mainly determines the duration of the lag phase.

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Self-assembly of polymer solutions containing zirconium oxide nanoparticles in mixtures of organic solvents and water in the course of vaporization of the solvents is interesting as one of preparation methods to obtain photonic crystals. In the preceding paper, we reported that the water droplets formed by nucleation were regularly arranged and then collapsed due to aggregation and coalescence of the droplets during the vaporization. In this study we tried to fix the self-assembled structure with keeping the regularity in the following two methods; (i) freezing of the self-assembled structure due to vitrification of the polymer and (ii) fixation of structures arising from photo-crosslink due to ultra-violet (UV) irradiation. We succeeded in freezing of the regular structures in the former method, while in the latter method the regular structures were collapsed due to viscoelastic effects of phase-separated structures induced by the UV irradiation.

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Some hydrogels can adsorb harmful heavy-metal ions, of which the property can be usable for purifying wastewater. One of the difficult problems for such a practical use is a slow rate of swelling process due to slow diffusion of the solvents in the hydrogels. In this circumstance, the authors have observed the swelling behaviors and SAXS profiles of the poly(acrylamide-co-sodium acrylate) gels after having soaked in several respective organic solvents for a while; they have found a considerable increase in the swelling rate as well as the swelling ratio in the gels and a definite peak in their SAXS profile.

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Adsorption of a carcinogenic agent, acridine orange, to DNA liquid crystalline gel (LCG) and DNA-combined poly(dimethylsiloxane) (DNA-PDMS) have been measured as a function of time. The adsorption process is represented by the stretched exponential function for both the DNA LCG and the DNA-PDMS. The experimental data of the adsorption process are compared with a simple model based on the diffusion process of acridine orange. For the DNA LCG, the adsorption rates are affected by preparation conditions. The DNA LCG with higher cross-linking density shows slower adsorption of acridine orange. The DNA-PDMS is a new DNA-based material with high elastic modulus, which is expected for use under high stress.

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The poly(sodium acrylate) gel physically cross-linked by aluminum ions were prepared at different temperatures. The gelation processes of the gels were examined using a dynamic viscoelastic measurement. The adhesion of the gels were also measured with the use of a simple tack-evaluation technique using a point contact. As a result, adhesion, stiffness, and time for the completion of the gelation strongly depended on the gelation temperature. The results were discussed in terms of the physical and chemical properties of gel surface formed at gelation.

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Thermosensitive poly(N-isopropylacrylamide) (PNIPAm) brushes grafted on SiO2-coated quartz crystal surface were prepared with a surface-immobilized initiator. By using quartz microbalance with dissipation monitoring (QCM-D) technique, we investigated the collapse and swelling of the brushes in water. Both frequency and dissipation of PNIPAm brushes were found to gradually change with a temperature range between 20-40°C, indicating that PNIPAm brushes undergo a continuous transition in contrast with PNIPAm chains in dilute solution exhibiting a sharp coil-to-globule transition. The nonuniformity and stretching of PNIPAm brushes as well as cooperativity between collapse and dehydration are considered to be responsible for the continuity. A hysteresis was observed in the cooling process. This is not only due to the intrachain and interchain interactions formed in the collapsed state, but also to the nonuniform structure and stretching of the high-density brushes.

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