The carbohydrate composition of the beet pulp [the residues of sugar beet (Beta vulgaris L.) extracts] was compared among three varieties, Monowhite, Hokkai 57 and Sugarman gold. Sugar composition analysis and sugar-linkage composition analysis showed that the carbohydrates in their alcohol-insoluble materials have features in common. However, total phenolic acid content was found to be different among them. In addition, the conditions for saccharification of beet pulp by commercial enzyme preparations were investigated using 16 kinds of crude enzyme preparations. Upon enzymatic saccharification of beet pulp, the 0.1 M NaOH pretreatment is very effective to increase the amount of monosaccharides.

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Cu powders with different diameter and mass were compacted on quartz substrates, followed by microwave (2.45 GHz) irradiation in air. Microwave heating of Cu powder was quite anomalous. Both peak and steady-state temperatures appeared during microwave irradiation. In small Cu powder particles, the whole of Cu particle was heated, while in large Cu powder particles microwave heating occurred locally on the surface of the Cu powder particles. The minimum mass over which the temperature rise was observed decreased with increasing mean particle diameter of Cu powder. Thus, the microwave heating of the Cu powder varied depending on both the mean particle diameter and the compacted mass of Cu powder.

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The present paper discusses the feasibility of frequency analysis of X -ray reflectivity data, which have been used extensively to obtain information on density, layer thickness, surface and interface roughness for layered materials. So far, the experimentally obtained data have been analyzed by least squares fitting to the theoretical reflectivity curve for assumed layered structures. As is often the case with non-linear systems, the solution is not generally unique. In fact, it is sometimes not easy to judge which structural parameters should be selected from several promising candidates that differ from each other to a fair extent but agree quite well with the experimental curve. The problem becomes even worse when one is not confident in the model, i.e., the number of layers etc. Assuming that several additional layers could improve the degree of fit, this raises the question of whether such a model should be accepted or not. The advantages of using frequency analysis, such as Fourier and Wavelet transform techniques, is that one can start from analysis which does not rely on the model too much. As the analysis gives a rough sketch of the electron density profile of the sample, one can decide which models should and should not be chosen. Furthermore, filtering specific frequency components of the data can help to see some morphology changes in the specific interface.

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GISAXS measurement activities on semiconductor nanodots and metallic clusters/nanodots at Photon Factory and SPring8 by us are presented. Semicondutor nanodots have been one of the most well known inorganic materials examined as a model sample for GISAXS. Comparing the GISAXS results from the second generation source and those from the third one, it is concluded that the second generation would be sufficient if the conventional beam size and the coherence are required. Size, shape and spatial arrangements of only single layer of encapsulated nanodots have been assessed by the GISAXS measurements at Photon Factory. The examples shown in the present manuscript suggest that conventional SAXS beamlines at second generation source have enough potential to explore time-resolved measurements on the evolution of nanostructures at surface. Some extensions concerning GISAXS measurements are discussed.

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We studied multilayers of self-assembled Ge nanowires grown on silicon (113) surface by solid-source molecular beam epitaxy using grazing-incidence small-angle x-ray scattering combined with x-ray reflectivity. Quantitative analyses show that the embedded nanowires retained their trapezoidal shape along the [110] direction, but are significantly subjected by interdiffusion of Si at their surrounding facets even at the growth temperature of 400C. The Si interdiffusion is remarkable at the sides of the nanowires but not at the top and/or bottom of them. The diffusion lengths are 5.2 and 0.2 nm at sides and top/bottom, respectively, for the nanowire with 20.5 nm in width and 1.6 nm in height.

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We survey the current status of reflective neutron optical devices, compound refractive and magnetic ones for enhancing the effectiveness of the beam utilization to extract physics information of samples.

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We set up a laboratory level X-ray CTR measurement system using a multilayer focusing mirror and a channel-cut asymmetric Ge double-crystal for a beam squeezing and an imaging plate as a 2D detector. Even though the intensity of the laboratory X-ray is by 700 times lower than that of the synchrotron X-ray, good enough signal/background ratios were achieved by the laboratory X-ray system for a reasonable measurement time of 100 minutes. This measurement system was applied to GaN/GainN/GaN heterostructures on sapphires, which were difficult to obtain a good signal/background ratio using synchrotron X-ray CTR measurements system, and reasonable CTR data were obtained. In distributions in GaN/GainN/GaN very different from those designed were obtained.

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Determining electron density in a material model-independently by X-ray diffraction has been a critical problem and actively studied since the middle of the 20th century. All the information that can be experimentally obtained by X-ray diffraction is only on intensity distribution, so that the information on the phase of scattering amplitude is lost, which prevents us from retrieving electron density model-independently. This is the so-called 'phase problem'. The phase problem in surface and interface crystallography has been one of interesting subjects in recent years. The present paper will focus on recent progress in solving the phase problem in surface and interface crystallography.

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X-ray Reflectivity under transmission geometry (Transmitted X-ray Reflectivity (TXR)) is a promising technique which enables us to make in situ and non-destructive observation of buried interfaces. In this study, we have investigated a deeply-buried interface structure between a thick Ga layer and SiC(000l) at various temperatures with synchrotron radiation. Above 500°C, specular TXR measured at an angle of incidence close to the critical angle for total reflection abruptly decreases. In the subsequent heating, an enhancement in diffuse scattering close to the specular TXR was observed above 1200°C, indicating morphological variations on the interface. The TXR measurement shows that an onset temperature of atomic-scale interface evolution is unexpectedly low at the deeply buried interface between Ga and SiC.

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Glancing-angular dependence of the fluorescence intensity from a layered sample typically shows Kiessing fringe similar to an X-ray reflectivity curve, and it can be explained by a concept of the X-ray holography, because X-rays directly reaching at a layer emitting fluorescence act as reference waves in holography, and X-rays singly reflected at interfaces act as object waves. In the present work, to prove the validity and availability of this idea, we designed a Pt/Si/Ti/ Ag/Si multilayer, whose top Pt layer was ultra-thin film and the holographic oscillations in angular dependence of the Pt La X-ray fluorescence intensity from Pt/Si/Ti/Ag/Si multilayer were evaluated theoretically and experimentally. In the theoretical study, depth positions at the three interfaces of Si/Ti, Ti/ Ag and Ag/Si were successfully reconstructed in the magnitudes of Fourier transforms of the oscillations in the angular dependence of the Pt La X-ray fluorescence intensity, whereas magnitudes of Fourier transforms from the X-rat reflectivity showed quite different tendency. In the experimental study, peaks corresponding to the interfaces of Ti/ Ag and Ag/Si appeared in the magnitude of the Fourier transform of the oscillation in the angular dependence of the Pt La X-ray fluorescence intensity.

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Gangliosides, belonging to species of glycosphingolipids (GSLs), are known to be involved in the formation lipid microdomains, so-called lipid rafts, on plasma membrane surfaces. The physicochemical properties of gangliosides deeply relate to the physiological functions of lipid rafts such as cell signaling. Previously we reported various unique characteristics of ganglioside aggregates and their complexes with other lipids. Due to the presence of oligosaccharide chain in the head portion, ganglioside molecules are very hydrophilic and form micellar structures in aqueous solvents. In this report we show the results of the hydration property of ganglioside micelles depending on alcohol concentration and species. The present results indicate that the increase both in the concentration and the number of hydrocarbon of alcohol induces the significant changes in the hydration of the ganglioside head portion and the packing parameter, which becomes to be more evidently seen with increasing the hydrocarbon chain length. It suggests that the competitive hydrophilic and hydrophobic interactions between polar and non-polar groups both in ganglioside and alcohol molecules sensitively affect aggregative properties of gangliosides.

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Soft interfaces such as polymer brush have played important roles in various technological applications. Neutron reflectivity (NR) is a powerful tool for the characterization of liquid/amorphous polymer and amorphous polymer/inorganic solid interfaces. In contrast, X-ray reflectivity (XR) and grazing incidence X-ray diffraction (GIXD) can characterize the crystalline state on the outermost surface and the electron density profile along the thickness direction, respectively. In this presentation, recent progresses in the characterization of polymer brushes by NR, XR, and GIXD is introduced.

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We investigated the high-temperature YBa2Cu3O7-x superconducting films by using a free electron laser (FEL). The method is a type of photoelectron spectroscopy called a free electron laser internal photoemission. The spectrum of the photocurrent induced by FEL was measured in the case of 15 K and 100 K. We estimated the superconductive gap energy of YBa2Cu3O7-x by comparing the photocurrent spectrum of the superconductive state with that of non superconductive state.

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Annealing process of Y2O3 thin film produced by metal organic decomposition method was analyzed by x-ray reflectivity (XRR), x-ray diffraction (XRD), and atomic force microscopy. The annealing process was divided into two stages, stage I and stage II with respect to the annealing time. In the stage I, nuclei of Y2O3 nano-crystals were scatteringly formed in the Y-O precursor film just after the temperature rising. As the annealing progresses, expanding nano-crystals filled up the film and covered the surface smoothly, resulting in a clear XRR oscillation. From XRD analyses, volume-weighted average diameter of the nano-crystals to produce the smooth surface was estimated to be ~ 10 nm. In the following stage 11, the Y2O3 nano-crystals did not expand any more; the crystals did not make a large domain by bunching. On the other hand, degenerative XRR oscillation in stage II revealed that stress at the grain boundary forces up the nano-crystals, resulting in rough interface and/or surface of Y2O3 thin film. Besides that, XRD peak was shifted to higher angle in this stage, indicating that the surface energy of the Y2O3 nano-crystals was so small that the crystal lattice was compressed without release of the internal energy.

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Structural variation of shape memory alloy Au50.5Cd49.5 with different temporal scale is investigated by X-ray diffraction. We found that once the crystal undergoes the Martensitic transformation, several spontaneous variations in crystal structure simultaneously occur. A 1/f type spectrum is observed in structural fluctuations of (112) surface in the frequency range of 1/100 Hz to 1 Hz. Structural fluctuations with the period of ea. 200 seconds are recognized more than 100 hours after the phase transformation. An ultraslow structural change over 53,000 hours (six years) is found, indicating a novel structural relaxation beyond the well-known slow relaxation referred to as rubber-like-behavior.

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An X-ray crystal truncation rod (CTR) scattering measurement system was set up using X-ray diffractometer that has a conventional X-ray source, i.e., rotating anode X-ray tube. Optical parts such as a collimating-multilayer mirror and an asymmetric Ge(220) monochromator to obtain condensed Cu-Ka1 beam and a set of slits to avoid scattered X-rays were installed. An imaging plate was used as a detector. It took 100 minutes for the X-ray CTR scattering measurement using the present system. Analysis of the X-ray CTR scattering spectra which were obtained using the present system showed that almost the same interface structures as those obtained using the SR were represented for the same samples. It suggests that the present measurement system with the conventional X-ray source is useful for the investigation of semiconductor heterostructures.

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Grazing-incidence small-angle X-ray scattering (GI-SAXS) technique was applied to examine self -assembled InAs quantum dots buried in amorphous arsenic cap layer. The size and the shape assessed from Born approximation of the model structures suggested that the shape of the InAs nanodots grown by molecular beam epitaxy for 2ML and 4ML showed a morphological transition from a dome shape into facetted structure.

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Very thin silicon-germanium-on-insulator (SGOI) substrates have been investigated using the total-external-reflection x-ray diffraction technique (TER-XD). The results show that the Ge segregation layer was formed at the interface between the oxidization layer and the SGOI layer. In-plane diffraction using TER-XD also shows that the Ge portion decreased with increasing incident angles of x-rays, suggesting the inhomogeneity of Ge distribution in the SGOI layers. These results are consistent with the previous work concerning to the Ge oxidization, suggesting additional annealing procedure will be required to increase crystalline quality of SGOI layers.

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We studied the interfacial lattice strain of Si02/Si(100) formed by high-pressure oxidation with extremely asymmetric X-ray diffraction using synchrotron radiation. From the dynamical diffraction calculation, we analyzed that the lattice spacing of oxidized silicon is compressed compared to that of the ideal crystal. By comparing wavelength dependence of integrated intensities of rocking curve obtained by calculations and experiments, we found that the conditions during oxidation influenced the magnitude of the lattice strain. The higher the oxygen pressure was the more compressive strain was introduced. Moreover, for higher temperature, more compressive strain was introduced. The interfacial lattice strain introduced in high pressure oxidation is comparable in magnitude to that introduced in dry oxidation even if the oxidation done at low temperatures.

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Strain field under Si3N4/Si(001) interface formed by nitrogen-hydrogen (NH) radicals (the Xe/NH3 plasma nitridation) was investigated by using a multiple-wave X-ray diffraction phenomenon, i.e., interaction between Bragg reflection and crystal-truncation-rod (CTR) scattering. Information on distribution of strain field induced by Si3N4/Si(001) interface was qualitatively obtained, and compared with the results of Si02/Si(001) interfaces formed by the thermal oxidations (wet and dry oxidations) and the Kr/02 plasma oxidation; strain field induced the nitridation by NH radicals was similar to that by the Kr/Oz plasma oxidation, but different from those by the thermal oxidations.

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We succeeded in epitaxial growth of Sr film on Si(111) with an atomically abrupt hetero-interface in spite of the large lattice mismatch of 12%, by introducing a H monolayer on Si. In order to identify the buried H layer, we have carried out combination analysis by neutron reflectometry, multiple-internal-reflection fourier-transform infrared spectroscopy (MIR-FTIR), and transmission electron microscopy (TEM). We have found different neutron reflectivity profiles using the contrast variation between H and D atoms. Furthermore, IR peaks indicating the chemical state of the Si-H bond shift to the lower frequencies during Sr deposition, due to static interaction between the Sr and buried H atoms. These results suggest the existence of buried H layer at the hetero-interface acting as an effective buffer layer to manage the highly mismatched system.

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La-substituted bismuth titanate (BLT) thin films formed directly on Si(IOO) substrates by using sol-gel methods have shown ferroelectric property and a preferred c-axis orientation depending on crystallization temperature. Since the spontaneous polarization and leakage current of BLT thin film strongly depend on the crystal orientation and it affects the electrical characteristics of the thin film memory devices, the investigation of orientation in the BL T film is important for the memory device development. X-ray diffraction analysis clearly showed the change in the c-axis orientation of the BL T film during the crystallization at 600 °C. The 00/ diffraction from the crystal the c-axis of which was normal to the surface was slightly observed in the sample crystallized for 5 minutes at 600 °C, and the diffraction peak clearly appeared after 10 min and then the intensity decreased gradually. In contrast to this behavior, the in-plane c-axis orientation was clearly seen in the BL T crystallized only for 5 minutes and it was almost independent of the crystallization duration. The X-ray reflectivity analysis showed that the ~ 1 nm-thick interface layer was formed by 10 minutes at 600 °C. The in-plane c-axis orientation could be related to the crystal structure of silicon, and the formation of the preferred orientation might compete with the interface layer formation at the early stage of crystallization.

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We have devoted our efforts toward developing transmission X-ray diffraction (TXD) for surface and interface from the viewpoint of realizing more efficient and precise structural analysis than the conventional surface X-ray diffraction. Here, we investigated bismuth lines embedded in a Si(001) substrate, which are promising templates applicable to nanometer-scale device, by TXD. In our experiments with synchrotron X-rays typical one-dimensional diffraction patterns were observed, which obviously indicates that the bismuth lines are still preserved in interface at the atomic scale.

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X-ray diffraction measurement (the ‘X-ray obvious-at-a-glance analysis’) of Bi atomic wire after burial in an epitaxial Si layer was performed near the Bi LIII absorption edge; X-ray diffraction patterns from buried one-dimensional structure were obtained, and their intensities changed drastically near the absorption edge. This gives evidence that the buried one-dimensional structure contains Bi atoms.

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The x-ray reciprocal-lattice space imaging (X-ReSI) method is a single-exposure x-ray diffraction technique which records the reciprocal-lattice pattern of a fixed crystalline nanostructure using a 2D detector. The typical exposure time is a few seconds to a few minutes. We describe the methodology, instrumentation, and expressions used for geometrical analysis in this technique. The technique was applied to study buried Bi nanoline structures. The results of the application reveal that line structures in samples capped with an amorphous Si layer and having no cap layers still remained with a non-detectable amount of the 2 x n atomic structures though Bi nanolines embedded in Si was found to have a 2 x n superstructure having Bi dimer bonds. This underscores the strength of the x-ray reciprocal-lattice space imaging method as a point-and-shoot technique for quick structural analysis.

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A crystallographic structure of an iron oxalate ultra-thin film grown on an ultra-smooth sapphire (0001) substrate was analyzed using synchrotron x-ray reflectivity and grazing incidence x-ray diffraction. The results show that the iron oxalate layer formed in crystal. In-plane diffraction measurements show the structure of the layer is random, and out-of-plane grazing incidence diffraction measurements show that the iron oxalate structure of the layer is affected by the step structure of sapphire surface, assumed to bond to the step edge.

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The surface structure of reconstructed Pt(211) has been studied using surface x -ray diffraction (SXD). Pt(211) reconstructs to (2 x 1) structure after annealing to 1400 K, whereas the surface has (1 x 1) structure after annealing at T 1200 K. Crystallographic analysis of the x-ray diffraction from the reconstructed surface shows a 2-missing-row structure. The space between the 1st and 2nd layers is contracted by 16 % compared with that of bulk-terminated Pt(211). The multilayer relaxation occurs between the topmost and the 5th layer. The optimized structure of the (2 x 1)-reconstructed surface is different from the structure predicted by DFT calculations.

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Properties and structures of adsorbed films on mixed aqueous solutions of sodium dodecyl sulfate (SDS) and a trace amount of 1-dodecanol (DD) were investigated by film balance experiments, a Brewster angle microscopy (BAM), and a quick X-ray reflectometry (q-XR) at 20 C. Pouring the aqueous solutions of the surfactants into a trough, the surface pressure first increased up to certain maximum values due to adsorption of the surfactants at the air/solution interface, but after a while it started to decrease probably due to evaporation of DD. BAM observation showed formation of holes of fluid phase in homogeneous condensed-phase monolayers in the course of surface pressure decrease. The q-XR technique was applied to the adsorbed films at the beginning stage of destabilization in order to characterize the film structures at the molecular level.

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Natural cocoa butter is known to exhibit five structural phase transitions. In situ observation on these phase transitions in surface region has been performed by a combination of grazing incidence X-ray diffraction and X-ray Reflectivity (XR) to compare the phase transitions in bulk. A surface-induced preferred orientation of constituent oil molecules is found, of which origin is the same as the diffuse scattering observed in bulk samples. A novel double-layer to single-layer phase transition is found by XR of Si-supported ultrathin films with thickness of several nm, indicating the anisotropic nature of inter molecular interactions.

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The intensity of x-ray propagation in surface layer materials characterized by a complex refractive index that changes continuously with depth was derived, and with use of the result, an analyzing method for evaluating the depth profiles of the strain distribution in the surface layer was studied. In this study, analyzing the incidence angle dependence of the scattered angles of diffracted x-rays from polycrystalline in surface layer with surface roughness, the depth profile of the strain in the surface layer is obtained. And, the influence of surface roughness in depth profile analysis of the strain distribution is studied.

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An x-ray reflectivity measurement system has been installed in the bending-magnet beamline, named BL15, at the Saga Light Source. This beamline provides synchrotron radiation in the energy range from 2.1 to 23 keV for the performance of x-ray diffraction experiments, x-ray reflectivity measurements, etc. To test the performance of this reflectivity measurement system, we have analyzed the interface of thin films with nanometer-scale thickness on semiconductor substrates. The reflectivity of the order of 10-7 has been observed for a 50-nm thick film of thermal SiO2 on a Si wafer. We have fitted the calculated reflectivity profile with a single layer model to the data, and have obtained the value of thickness. In addition, we have performed grazing-incidence small-angle x-ray scattering (GISAXS) experiments on a MnPt thin film.

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Temporal and spatial behavior of WO3 plasma plume in pulsed laser deposition process have been studied using emission spectroscopic method. Three dimensional study of the plasma plume suggested that the emission plasma plume grew toward substrate direction after the laser irradiation on the target to 2.0 11s, and they disappeared gradually. Emission from the tungsten atoms was dominated in the plasma plume, and there was no emission species such as W ions, O neutrals and molecular species in the plasma plume. W I emission species move with high speed of 5~9 km/s at the delay times (tau d) from 0.5 to 2.0 micro s after the laser irradiation on the tungsten target surface. We also prepared WOx thin films on flexible ITO substrates by PLD method, and it is confirmed that they worked as electrochromic display.

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This paper presents a comparison study of photoluminescence (PL) properties of freestanding silicon nanocrystals (Si-ncs) prepared by electrochemical etching and nanosecond pulsed laser ablation in two liquid solutions i.e. de-ionized water and spin on glass. The Si-ncs fabricated by electrochemical etching show visible room temperature PL with peak maximum at 680 nm. The PL peak of Si-ncs synthesized by pulsed laser ablation is significantly blue shifted with maximum centered at 420 nm after aging for at least 8 weeks. Laser ablation process in electronically compatible liquid spin on glass accelerated Si-ncs surface passivation. As a result the aging process was shortened to 24 hours with the same PL peak position. PL intensity of Si-ncs embedded in SOG increased with the laser fluence for ablation. A Si-ncs formation scheme during the nanosecond pulsed laser ablation in both liquids is proposed to explain obtained results and discussed in detail.

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The azafullerene C59N is synthesized by a nitrogen plasma irradiation method, which has been confirmed by the analysis of mass spectroscopy. The encapsulation of C59N inside single-walled carbon nanotubes (SWNTs) is practiced via a vapor diffusion method. Electrical transport properties of C60 and C59N encapsulated SWNTs are investigated by fabricating them as the channels of FET devices at room temperature. It is found that the electrical transport properties of C60@SWNTs exhibit the enhanced p-type characteristics compared with the case of pristine SWNTs, whereas C59N@SWNTs show the n-type behavior. The novel transport properties of peapods can be explained by the charge-transfer effect, which can modify the electronic structure of SWNTs.

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Single-walled carbon nanohorns (SWCNHs) can be produced by an arc-in-water system, in which N2 gas is injected in an arc plasma zone in a hollow graphite cathode. To decrease the cost for synthesis, it is important to optimize the reaction condition when low cost electrodes (low purity graphite) are used because high purity graphite is fairly costly. In the present study, graphite electrode of a low graphite purity (C:97.5%, SiO2:1.4%, Al2O3:0.38%, Fe2O3:0.29%, etc.) was used for the electrodes, and the investigation of the operational paramters in the N2-injected arc -in-water method was carried out regarding the depth of the hole on cathode and velocity of the electrode motion to keep the arc plasma. It was observed in a transmission electron microscope that the purity of the SWCNHs from the low-purity graphite electrodes seemed as 70-80 %. As a result, the cost to synthesize SWCNHs became one order magnitude lower compared with the conventional condition using high purity graphite electrodes. At this condition, the yield and the production rate of SWCNHs were about 8 % and 18 g/h, respectively. In addition, the mechanism of the effect of the above parameters is discussed based on the resident time and the concentration of carbon vapor inside the cathode hole.

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An encapsulation of biomolecules such as DNA and ionic liquids into single-walled carbon nanotubes (SWNTs) is demonstrated using an ion irradiation method in electrolyte plasmas. The DNA negative ion irradiation can be controlled by varying electric fields and irradiation time. Based on the Raman spectroscopy analysis, DNA is confirmed to be inserted into SWNTs. Furthermore, the positive and negative ions of the ionic liquids are also encapsulated into SWNTs and modify the electronic state ofSWNTs depending on the polarity of the ions.

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Surface modification of Polyethylene terephthalate (PET) using two types of atmospheric pressure plasma jet, silent discharge and glow type discharge, was investigated. The water contact angle of PET surface was improved by plasma treatments using the silent discharge and glow type discharge plasma jet. XPS results showed that the ratio of oxygen-containing polar group in PET increases and it is consistent with the contact angle measurement. Comparing the types of plasma treatment, there is much oxygen-containing group in the glow type discharge.

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A surface-wave-excited plasma (SWP) source was applied to improvement of the surface hydrophilicity of polytetrafluoroethylene (PTFE). The contact angle of PTFE surface was observed to be drastically decreased by the SWP treatment within a very short time less than 5 s. The total ion dose in the PTFE sample is one of very important parameters to determine the change in the PTFE surface hydrophilicity by the plasma treatment. From X-ray photoelectron spectroscopy (XPS) measurement, drastic changes in the surface atomic composition, i.e., decrease in F atomic composition and increase in N and 0 atomic compositions were observed after the plasma treatment. Atomic force microscope (AFM) measurement indicated that the increase in the surface roughness after the plasma treatment. As origins of the hydrophilicity improvement, increases in both hydrophilic chemical bonds (C-O, C=O) and surface roughness were pointed out.

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The purpose of this study was to control size and composition of Sn-Ag-Cu nanoparticles prepared by Ar or Ar-H2 arc. The vaporization and condensation rate should be controlled to prepare alloy nanoparticles. These rates could be controlled by the composition of raw material and H2 concentration. An increase in H2 concentration in the arc led to an increase of Cu fraction in prepared nanoparticle. An increase of Sn fraction in nanoparticle made particle size larger. The obtained results indicated that the nanoparticles were spherical shape. Another purpose of this study was to investigate the vaporization mechanism from molten Sn-based alloy with Ar-H2 arc. The vaporization enhancement of Cu from Sn-Ag-Cu mixture by hydrogen in arc plasma was confirmed. The vaporization enhancement would be attributed to the activity modification by hydrogen in molten metals.

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Decomposition system of liquid waste by DC water plasmas generated at atmospheric pressure was developed. The developed water plasma torch is a DC thermal plasma generator of coaxial design with a cathode of hafnium embedded into the copper rod and a nozzle-type copper anode. The plasma torch can generate 100%-steam plasma without a commercially available steam generator. The water plasma system is a portable light-weight system that does not require any gas supply. The plasma system has high energy-efficiency since cooling water is not needed. Methanol or ethanol used as model substances of liquid waste was mixed with water for plasma supporting gas. Rapid and complete decomposition for these alcohols produce H2, CO, and CO2 in the decomposed gas. The decomposition rate as well as the decomposition mechanism was determined by gas chromatography and mass spectrometry. The water plasma system can be used for industrial application of liquid waste decomposition.

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Gas Tungsten Arc (GTA) is suitable as a heat source device for many applications because it can stabilize high temperature arc plasma easily by employing shielding gas. In many cases, MHD simulation model assuming the local thermodynamic equilibrium (LTE) is utilized for analyzing property of GTA. Although the L TE assumption is effective to evaluate high temperature region in the arc column, it is difficult to apply it to low temperature region such as the fringe of the arc column or the sheath regions closed to the electrodes due to decrease of energy exchange. In order to consider the effect of chemical reaction between the arc plasma and the material surface, we have developed a simulation model of GTA assuming chemical and thermal non-equilibrium. In this paper, as a first step of the study, heat source property of argon GTA employing a water-cooled copper anode was simulated.

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Tungsten Inert Gas (TIG) arc is the most widely employed type of a plasma torch and enables to produce arc plasma with high energy density. Therefore it is suitable as a heat source device especially for processes to require concentrating the heat input at a point. On the other hand, Tube Cathode Arc (TCA) to be a kind of TIG produces the arc plasma by introducing inner shielding gas through the central hole of the tube cathode. As the basic heat source property of argon (Ar) TCA, the property of the arc plasma and the heat input intensity onto a water-cooled copper anode for various inner shielding gas flow rates were numerically analyzed. Furthermore, by employing stainless steel SUS304 anode, the geometry of its weld penetration was also predicted. The results were compared with those for the conventional TIG. As a result, it was shown that since TCA enables to heat the target material uniformly by controlling the inner shielding gas flow rate and preserve it from damage due to excessive heat input during the process, it is suitable for processes such as brazing, buildup or thermal spraying.

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A gas tungsten arc in helium is modeled taking into account the contamination of the plasma by the metal vapor from the weld pool surface. The whole region of gas tungsten arc welding, namely the tungsten cathode, arc plasma and weld pool, is treated using a unified numerical model. A viscosity approximation is used to express the diffusion coefficient in terms of the viscosities of the helium gas and the iron vapor. The two-dimensional distributions of temperature, velocity and iron vapor concentration are predicted, together with the weld penetration at atmospheric pressure. It is shown that the thermal plasma in gas tungsten arcs is markedly influenced by iron vapor from the weld pool surface.

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A simple bottom up method for the growth of ZnO nanoarrays using a chemical bath deposition has been widely used due to its promising application in the functional devices, ultraviolet light-emitting, chemical sensors, dye-sensitized solar cells, transparent conductor and piezoelectric materials. The morphology was strongly influenced by experimental conditions including chemical species in the solution, the level of supersaturation, the temperature and the nature of the substrate. Preparation of a ZnO seed template layer was necessary for growth of ZnO nanoarrays film. The effects of different substrates (such as slide glass, Si wafer and F-doped SnO2 coated glass) and zinc salts which resulted to ZnO seeds on the morphology of ZnO nanoarrays were investigated. Additionally, the influence of the surfactant-like polymer on the crystal morphology was addressed.

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Y -type zeolite membranes containing Na+ ions were synthesized on the outer surface of a porous a-alumina support tube by means of a hydrothermal reaction. The Na+ ions of the membranes were ion-exchanged with Sr2+ ions, and the separation properties of the membranes were investigated at 313 K for mixtures of N2 and O2. Although the exchange of Na+ ions with Sr2+ ions greatly increased the N2 adsorption capacity, the SrY-type zeolite membranes had oxygen over nitrogen selectivities (up to 2.1) and O2 permeances of the order of 10-9 mol m-2 s-1 Pa-1. Those findings suggest that N2 permeability was hindered by the Sr cations present that would interact strongly with N2, resulting in an increased O2 permeability, compared to N2.

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We report a simple approach to prepare An/polystyrene (PS) composite photonic crystals. In this approach, Au nanoparticles protected by thiol molecules were synthesized by two-phase system using dimethylamine-boran as reducing agent at low temperature. PS microstructures containing the obtained Au nanoparticles were prepared by polymerization of styrene monomer in the presence of Au nanoparticles using a silica inverse opal as template. The composites with different Au content were prepared, and their structural and optical characteristics were characterized by transmission electron microscopy (TEM) and optical absorption spectroscopy, respectively. The relationship between microstructures including particle size and volume fraction of metal phase, and optical properties has been systematically evaluated. These characterization indicate that reflection peak of the obtained composite can be controlled by the volume fraction of Au nanoparticles.

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The novel amphiphilic graft copolymers were synthesized, which consist of methoxy-endend poly (ethylene glycol) (PEG) as a hydrophiphilic segment and pyridine as a hydrophobic and metal affinity segment (Py-g-PEG). Py-g-PEGs formed micelles and their physicochemical properties were intensively investigated in terms of critical micelle concentration, critical surface tension and micelle size. Furthermore, the gold nanoparticles (Au-NPs) were prepared using the Py-g-PEG polymeric micelles. Py-g-PEG has attained the long term interfacial stability by employing the multi-point adsorption of the pyridine unit on the gold surface. Usually, Au-NPs are prepared by thiol derivative, which are well-known to readily lose the dispersion stability under oxidative condition. Note that Au-NPs protected by Py-g-PEG were drastically enhanced their dispersion stability under air oxidative and high ionic strength conditions.

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It is noted that three dimensional cellular aggregates (= spheroid) have the advantage to maintain the differentiation function due to their microenvironment nearer to in vivo tissue. In this study, we demonstrate the micropatterning of spheroids on a nonfouling substrate, followed by their transcription into poly(ethylene glycol) (PEG) hydrogel from the substrate. The spheroid-containing gel was intensively studied in terms of physicochemical and biological view points. PEG hydrogel was size selective of permeation due to the difference of crosslinking density, which was clearly ensured by swelling properties. Note that the spheroids maintained their function even after transcription, which may have the high utility to reconstruct large size organization (organoid) for tissue engineering.

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Glyco-dendrimers carrying sulfate saccharides were efficiently synthesized via a cycloaddition of click chemistry. The interactions with a lectin of wheat germ agglutinin were evaluated by fluorescence spectroscopy. The interactions with amyloid p peptide were evaluated by CD spectra, thioflavin T assays and AFM observation. The interaction with the lectin and amyloid P peptide were affected by the size of the dendrimer and the kind of saccharide.

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Novel saccharide surfaces with well-defined multivalency were prepared using glycodendrimer. The glycodendrimer a-mannose (a-Man) was synthesized and immobilized onto the acetylenyl-terminated gold substrate via click chemistry. The saccharide-immobilized substrates were evaluated with FTIR-RAS and XPS. The biological abilities of the saccharide-immobilized substrate were evaluated by quarts crystal microbalance (QCM) with the lectins of concanavalin A (ConA), and wheat germ agglutinin. The lectin binding to the glycodendrimer array was quantitatively analyzed, and the association constant (KA) was revealed according to Scatchard plot. The kinetic constants were increase by glyco-dendrimer immobilization, and the multivalent effect of saccharide-lectin was exerted effectively.

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