The application of XAFS spectroscopy is described for the determination of the speciation of sulfur and various hazardous or key metals in both coarse (>2.5μm) and fine (<2.5μm) fractions of particulate matter (PM) emitted in three different fossil-fuel combustion processes. The three processes consisted of (i) combustion of residual oil, (ii) combustion of various eastern and western U. S. coals, and (iii) combustion of diesel fuel formulations in an engine. Sulfur was found to exist in mainly sulfate forms in the emissions from all three processes, although minor to significant fractions of the sulfur were also present as thiophenic sulfur, elemental sulfur, and various other sulfur forms, depending on the fossil fuel, the combustion conditions, and the particle size of the collected fraction. Combustion of residual oil tended to form metal sulfates predominantly, although the coarse fractions (PM_2.5+) also contained minor amounts of sulfides of Fe, Cu and Ni, while the fine fractions (PM_2.5) contained oxides instead of sulfides as their minor components. Due to the presence of aluminosilicates in the coal, metal species in coal emissions were more complex. Chromium was present entirely as Cr³⁺ in both fine and coarse PM from combustion of eastern U. S. coals, but significant fractions of the chromium were present as more toxic and carcinogenic Cr (VI) species in fine and coarse PM from combustion of western U. S. coals. In contrast, arsenic was present entirely as arsenate (As0₄^3-) species in all coal PM samples (and residual oil PM samples), regardless of origin. No evidence was found for the more toxic As (III) oxidation state in any sample. The zinc speciation in PM samples from combustion of coal samples was also found to vary with geographic origin of the coal. Zinc in PM samples from eastern U. S. coals was present mostly as Zn ferrite (ZnFe₂O₄), while the Zn speciation in PM from western U. S. coals was more complex. The XANES signatures of Zn in PM from both residual oil and diesel combustion processes were quite different from those of PM from coal combustion and suggestive of anhydrous zinc sulfate.
Comparison was also made of sulfur and zinc XANES spectra for PM collected on filters from the ambient atmosphere with those from the fossil fuel combustion processes. Significant differences were observed in both sulfur and zinc speciation.

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Wood is a prospective resource from viewpoint of sustainable development. The engineering evaluation of tactile warmth is treated as a good point of wood. The relationship of the contact surface temperature and the thermal effusivity is derived from the theoretical analysis of heat transfer phenomenon and proposed as measures to evaluate the tactile warmth. The measures review some knowledge on tactile warmth of wood. It is found that the sensory warmth of wood has a high and positive linear correlation with the logarithm of the contact surface temperature and that the material with a lower thermal effusivity feels warmer than the material with a higher one. The relationship explains rationally why each wood has large difference of sensory warmth in spite of their small difference of material properties. The relationship also explains the reason why wood has good tactile warmth regardless of the season, which is different from metals.

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For applying calcium-based (Ca-based) solid wastes to renewable source of calcium derived products, different calcium-based solid wastes from coal burnt ash, coal slag and iron slag were tested for dry sorption of HCl. The sorption capacities of Ca-based wastes for HC1 were related to the soluble alkali amount involved, as well as specific surface area of the solid. Coal burnt ash and slag treated by hot water and alkali curing were found to be greatly improved in HC1 sorption capacity, almost equivalent to that obtained by the use of conventional calcium oxide or calcium hydroxide.

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Computational inverse techniques are presented for inverse problems in the areas of material characterization using dynamic response in anisotropic inhomogeneous plates. In these techniques, the inverse problems are formulated into parameter identification problems, in which a set of parameters corresponding to the characteristics of material property can be found by minimizing error functions formulated using the measured displacement responses and that computed using forward solvers based on projected candidates of parameters. The forward solvers used in this work are the hybrid numerical method (HNM) and the finite element method (FEM). The HNM has been proven very effective for transient wave response analysis. The high efficiency of these two forward solvers paves the way for the inverse procedure to solve the inverse problems using waves. Three types of optimization algorithms: nonlinear least square method, evolutional method (genetic algorithm), and their combined method, as well as an identification technique: artificial intelligence method (neural network), are employed as the inverse procedure. Several application examples are presented. It is demonstrated in this work that these inverse problems in material characterization can be solved to a desired accuracy with high efficiency through innovative use of advanced computational techniques.

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Consumer electronic equipments are becoming small, portable devices that provide users with a wide range of functionality, from communication to music playing. The battery technology and the power consumption of the device limit the size, weight and autonomous lifetime. One promising alternative to batteries (and fuel cells, that must be refueled as well) is to use the parasitic energy dissipated in the movement of the wearer of the device to power it. We analyze in this work the current state-of-the-art and the future prospect of energy conversion from mechanical movement in the human environment to electrical energy based upon the piezoelectric effect. This is an interdisciplinary field where material technology and electrical circuits have to advance together to improve the conversion efficiency in order to reach the energy demands of the typical portable consumer electronic devices that will become in this way autonomous wearable devices.

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This paper is concerned with the theoretical treatment of transient thermoelastic problem involving an angle-ply laminated cylindrical panel consisting of an oblique pile of layers having orthotropic material properties due to nonuniform heat supply in the circumferential direction. We obtain the exact solution for the two-dimensional temperature change in a transient state, and thermal stresses of a simple supported cylindrical panel under the state of generalized plane deformation. As an example, numerical calculations are carried out for a 2-layered angle-ply laminated cylindrical panel, which is heated from inner surface. Some numerical results for the temperature change, the displacement and the stresses in a transient state are shown in figures. Furthermore, the influence of the radius ratio on the temperature change, the displacement and the stress distributions are investigated.

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We have succeeded in fabricating micropatterns of TiO2 thin films on self-assembled monolayers (SAMs). SAMs of OTS (octadecyltrichlorosilane) were formed on Si wafers and modified by UV irradiation using a photomask to generate octadecyl/silanol-pattern. They were used as templates to deposit TiO₂ thin films by the use of TDD (titanium dichloride diethoxide) dissolved in toluene. Amorphous films were selectively deposited on silanol regions. Line width variation of the pattern was improved to be well below the current electronics design rule, 5%. Dielectric constant of an as-deposited TiO₂ thin film, dielectric properties of TiO₂/SiO₂/Si interface and leakage current density were evaluated by measuring I-V and C-V characteristics of the MOS (metal-oxide-semiconductor) device. Rather low leakage current was observed under high electric fields and the TiO₂ thin film with the thickness -18 nm showed dielectric constant of -22 at 100 kHz, which is more than 5 times as large as that of a usual SiO₂ dielectric layer. However, the resistivity of the TiO₂ film was estimated to be not high enough and the dielectric constant depended on frequency, both of which are disadvantages for a gate dielectric.

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This study is a discussion of a new visual analysis technique for rock slope displacement. The presentation is based on data obtained from the system for monitoring displacement at a hydropower station in south China. A database technique, a three-dimensional displacement analysis model, and a visualization analysis technique make up the core of this study, and according to these techniques and methods, a set of software for the analytical slope displacement information system was developed.

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The effects of ion vacancy on the crystal structure and the electrical conductivity of perovskite-type oxides were investigated. The cation and oxide ion deficient perovskite-type oxides LnA_2-x, Ti₂AlO_9-d, (Ln=La, Nd; A=Ca, Sr) were synthesized. Single-phase samples of LnA_2-xTi₂AlO_9-d were prepared by heating at 1673 K in air in the compositional range of x=0-0.3 for both A=Ca and Sr. The crystal structures were cubic perovskite-type for A=Sr and orthorhombic perovskite-type for A=Ca. Lattice parameters of LnA_2-xTi₂AlO_9-d, increased with increasing amounts of A cation vacancies. All the samples exhibited semiconducting behavior in the temperature range of 573-1023 K in air. The measurements of conductivity for LnA_2-xTi₂AlO_9-d as a function of oxygen partial pressure revealed n-type conductivity at oxygen partial pressure less than 0.21 atm. The conductivities of LnA_2-xTi₂AlO_9-d, increased with increasing amount of A cation and oxide ion vacancies for both A=Ca and Sr.

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Liberation is very important to separate different materials from the wasted composites for recyclingthe components. It is necessary to develop the new crushing method to tear off the composites alongthe boundary of different materials. As the waste materials include many kinds of inorganic and organiccomponents, it is difficult to liberate them by conventional crushing and grinding methods. In this study, theexfoliations along the boundary of materials, such as, concrete, silicon with silica, nail in wood and liquidcrystal display have been investigated by electrical crushing (disintegration) method.

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The objective of this investigation was to separate silicon and silica for recycling by the liquid-liquid separationtechnique. In the preparation of silicon (Si) single crystal, a small amount of silicon is fixed on thesurface of silica (quartz, SiO₂) crucible. The used crucible is crushed for recycling both silicon and silicain high purity from the mixed powder. Zeta-potential of silicon and silica are almost the same at pH higherthan 3. Their separation by simple flotation is ruled out. However, their hydrophobic characteristics are differentin several different organic solvent from the measurement of contact angle. Therefore, the liquidliquidextraction is employed to separate silicon and silica. The result indicates that the organic solventmixed with dodecylamine acetate could extracted the silicon powder at high purity (97-100%) with highrecovery from the silica powder in the water phase.

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Non magnetic foundry materials such as the austenitic stainless cast steel had not been used for abrasionresistant materials, because their hardnesses were very low. Usually, ceramics, cermets and cemented carbidesare used for the abrasion resistant materials even though they are expensive compared with foundrymaterials.
In this study, WC powder were inserted by using the austenitic stainless cast steel (JIS SCS13A) and theaustenitic cast iron (JIS FCA-NiCr202) for producing surface hardened non magnetic materials. The meltingtemperature (pouring temperature) is lower in the austenitic cast iron than in the austenitic stainless cast steelwhile the fluidity of the melts is superior in the austenitic cast iron. For the WC powder inserted specimens, the hardness, the abrasion resistance and the magnetic property were examined.
As a result, it was found that the hardness in the region of inserted WC powder was much higher than thatof base metals of the cast steel and the cast iron, and that the magnetic permeability did not change by theinserting. Especially, a lot of WC powder was found to dissolve into the base metal in the cast steel than inthe cast iron. In the case of the cast steel, Fe₃W₃C compound phase having high hardness of HV800 wasformed in the region of inserted WC powder. The hardness in the region of inserted WC powder was higherin the cast steel than in the cast iron, because the cast steel contained a lot of chromium compared with thecast iron.

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Electrical Sialons which have some TiN contents were joined with Ag-Cu-Ti active brazing metal layerhaving a thickness from 30μm to 400μm at a temperature from 1113 K to 1213 K in a vacuum. Residualstress in the brazed joint specimens was not observed when the thickness of brazing metal layer was 30μm. However, the residual stress of 80 MPa was detected when the thickness of brazing metal layerincreased up to 400ktm. When the brazing temperature was 1113 K, four-point bending strengths of 520MPa and 310 MPa were obtained for the brazed joint specimens with the thicknesses of brazing metal layerof 30μm and 400μm, respectively. While the four-point bending strength increased as the brazing temperaturewas raised. The maximum value of the four-point bending strength was about 700 MPa which was obtainedat a condition of the brazing metal thickness of 30μm and the brazing temperature above 1163 K.However, the four-point bending strength decreased with increasing the bending test temperature. A remarkabledecrease of the bending strength was observed at the test temperature of 873 K, in which the bendingstrength was 300 MPa.

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Spheroidal graphite cast irons are widely used for auto parts because they have large degrees of freedomin shape and are inexpensive. When they are welded, however, they show serious drawback of crackgeneration due to excess carbon at thehardened region of heat-affected zone. We have studied ondecarburized spheroidal graphite cast iron which has a possibility of welding because of graphite free in thesurface region. In the present study, some characteristics of the decarburized layer in the spheroidal graphitecast iron were investigated.The results obtained are as follows.
Growth of decarburized layer is controlled by diffusion of carbon atoms toward the surface region in theiron during the heat-treatment and there is a critical temperature of 930 K for the decarburization, belowwhich decarburization does not occur. When the area ratios of the decarburized layer to whole sectional areain the rod-shaped tensile test specimen was defined to be a ratio of decarburized layer, the tensile strengthof the specimen scarcely influenced by the ratio of decarburized layer. However, when theoverdecarburization was processed, the tensile strength showed a tendency to decrease.
Therefore, it should be noted in practical use of the decarburized spheroidal graphite cast iron that theexcessive decarburization makes the strength of thin parts of the iron to decrease.

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In this paper, two experiments for locally hard facing of cast iron and cast steel will be presented. In thecase of locally hard faced spheroidal graphite cast iron with hard alloy briquettes, the inserted layer asformed with penetration of the molten cast iron among tungsten carbide (henceforth, it is described as WC) particles in the hard alloy briquette. The base metal of inserted layer showed a microstructure of gray castiron due to a hindrance to spheroidalization caused by a reaction the molten cast iron to the elements of Wand Co in the hard alloy. The hardness of mother spheroidal graphite cast iron was about Vickers hardness (henceforth, it is described as HV) 200 while the hardness of the inserted layer ranged from HV600 toHV1600.
In the case of locally hard faced cast steel, the inserted layer was also formed with similar process to thatof the spheroidal graphite cast iron, while intermediate phases with very hard complex carbide were formedat the bonding region between the inserted layer and the base metal. The hardness of mother cast steel wasabout HV300, while the hardness of the inserted layer ranged from HV800 to HV1400. Especially, the intermediatelayer with complex carbide showed the highest hardness of HV1800. Therefore, the inserted methodswith hard alloy particles are considered to be a very effective one for locally hard facing of cast iron andcast steel.

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Iron matrix transformation behavior and high temperature strength of Fe-25mass%Cr-C-B cast alloyswere investigated using thermal expansion method and compressive test, respectively. Five kinds of eutecticalloys were destabilized at temperatures of 1173 K, 1273 K and 1373 K for 1800 and 18000 seconds, followed with air cooling. Compressive test was made on Fe-25Cr-OC-2.2B, Fe-25Cr-2.2C-1.0B and Fe-25Cr-3.5C-OB eutectic alloys at temperatures up to 1073 K. Result of the work shows that Ms temperaturerises with the decrease in destabilization temperature, but the hardness becomes larger with the increase indestabilization temperatures, for the alloys with boron content. Compressive strength of all as-cast alloyswas above 2000 MPa at room temperature and above 100 MPa even at 1073 K. The true stress-true straincurves characteristics depended on the chemical composition of the alloys. The effect of destabilization heattreatment almost disappears at the temperatures above 873 K in every alloys.

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In order to study the supramolecular formations of guest-responsive cavitand derivatives in aqueoussolution, synthesis of water-soluble fluorogenic cavitands, which are modified with mono- and bis-pyreneunits (1 and 2, respectively), and their metal sensing abilities have been investigated. Compound 2 showedmonomer and excimer emissions in both an organic and aqueous, which was contained a 10 vol.% DMF, solution, whereas compound 1 indicated these two emissions in only aqueous solution. The fluorescencespectral patterns of compounds 1 and 2 were changed depending on DMF concentrations in an aqueoussolution. The extent of the excimer emission of 2 was the highest in a 50 vol.% DMF, whereas drasticdecrease of this excimer emission was observed in over 60 vol.% DMF. On the other hand, compound 1showed the highest excimer emission intensity between 10-30 vol.% DMF and middle emission wasrecognized in 30 vol% DMF. Finally, in over 50 vol.% DMF, no excimer emission of 1 was observed. Themovements of the appended units of these compounds in various DMF concentrations were studied by thefluorescence and UV spectra and MM2-minimized structures. A ratio of excimer and monomer emissionintensities of 1 and 2 were varied in 10-40 vol.% and 10-50 vol.% DMF contents in water, respectively. TheUV spectra patterns of 1 or 2 were different between in 10-40 vol.%, 50 vol.% and over 60 vol.% or 10-50vol.%, 60 vol.% and over 70 vol.% DMF aqueous solutions, respectively. The variations of fluorescence andUV spectra suggested that compounds 1 and 2 formed association dimer in 10-40 vol.% and 10-50 vol.%DMF aqueous solutions, respectively, and the canceling of these dimer formations was observed withincreasing DMF content or metal concentration. Furthermore, fluorescent spectral changes and MM2-minimized structures suggested that the association dimer of 2, which formed one pair pyrene excimer in 10vol.% DMF aqueous solution, was transformed into different configuration of association dimer makingplural pyrene excimer pairs in 20-50 vol.% DMF aqueous solutions. In order to evaluate the metal sensingabilities of 1 and 2 in a 10 vol.% DMF aqueous solution, the ratio of decrement of an intensity of excimeremission with an addition of metal cation was used as a detecting parameter. Compounds 1 and 2 exhibitedthe highest sensing abilities for Na²⁺ and Co²⁺, respectively.

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The changes of color, size and shape of Bombyx mori cocoon shells were observed from 25°C to 550°C. Only 1 % of the original cocoon shell weight remains as cocoon ash after treatment at 550°C. Theinorganic components were detected in the cocoon ashes such as calcium, potassium, sulfur, magnesium etc., using energy dispersion fluorescent X-ray spectrometer analysis system. The thermal properties of B. moricocoon shell subjected to heat-treatment were examined by thermogravimetry-differential thermal analysis-Fourier transform infrared absorption spectrometry (TG-DTA-FTIR) and scanning electron microscopy (SEM). Chemical changes started gradually at around 180°C, and a sharp decrease in weight was observedaround 280°C by TG curves. The IR bands appearing around 2380cm^-1 (-OH stretching), 1760cm^-1 (C=Ostretching), 1503cm^-1 (N-H stretching), 1085cm^-1 (C-N stretching) and 965cm^-1 (-NH2 stretching) become stronger as an exothermic reaction around 280°C takes place. This is probably due to the cleavingof the main chain and the accompanying decomposition of the cocoon fibers. Similarly, a SEM micrographof raw silk fibers treated at 300°C shows a microtubule in the middle of the fibers of about 25μm diameter.This suggests that the thermal reactions starts in the middle of the fiber and forms a microtubule.

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WC-14%TiC-8%Co cemented carbide of as-sintered was immediately quenched. In comparison with conventionalsintered specimen, the strengths of the quenched cemented carbides were increased by20.2%-32.8%. It was ascribed that the formation of the slip steps on WC grain's edge is induced by thermal-stresses during quenching.

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