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International audience; Solar energy-harvesting materials have significantly contributed to the development of energy-saving applications for several decades. We have mainly used a new concept composed of the electrophoretic deposition technique and photonic crystal structural engineering to understand the tunable light-absorption and electronic conduction properties. A hexamolybdenum cluster compound (denoted as the Mo6 cluster) was successfully functionalized on a tin pyrophosphate semiconductor integrated within an inverse opal photonic crystal. The size of the periodical pores, surface modification, and chemical composition of the infiltration material of the inverse opal film have been investigated to control the photonic bandgap in the visible range and the efficiency of the deposited Mo6 cluster. The photoactive Mo6 clusters act as a visible light harvester and generate an efficient photo-induced current upon light absorption that is enhanced by a slow photon effect occurring at the photonic stopband edges. The electron and proton are transferred in the inorganic-organic network via hydrogen bonds by a hopping mechanism to generate a rapid photoconductivity response during light irradiation. Specific attention focused on the role of humidity and temperature regarding the reproducibility of the experiments and the photosensitivity of the nanocomposite. The suitable tunable photo-induced conduction property in organic-inorganic materials opens a new opportunity for the applicability of cluster-based compounds in visible optoelectronic devices.

We report thermomagnetic properties in magnetically frustrated A-site spinel magnets of CoAl2O4, CoRh2O4, and cluster glass CoGa2O4 to comprehensively show the proximity effects of the Néel-to-spin-spiral (NSS) transition, which is predicted theoretically to occur in a magnetically frustrated A-site spinel antiferromagnet. The low-temperature magnetic phase remains controversial since the magnetic state of CoAl2O4 is in the vicinity of the NSS transition derived by the inherent magnetic frustrated interaction for an A-site spinel magnet and is also considerably sensitive to crystallographic disorder. The antiferromagnetic and spin-glass transitions were detected by measuring the direct-current and alternating-current susceptibilities and also thermoremanent magnetization (TRM) developing below the magnetic transitions at the Néel point (T N) and spin-glass transition temperature (T SG). The relaxation rate and the temperature derivative of TRM were both enhanced at T N and T SG, and they decayed rapidly above and below the transitions. We succeeded in extracting the relaxation time τ and other characteristic parameters from the isothermal relaxation of TRM, which was well fitted with a non-exponential relaxation form formulated by Weron based on purely stochastic theory in order to describe the originally dielectric relaxation. For the typical CoRh2O4 normal spinel (inversion-free A site) antiferromagnet and the CoGa2O4 random spinel spin-glass, the temperature variations of these parameters can distinguish the magnetic states. In contrast to the cases for CoRh2O4 and CoGa2O4, an enhancement of the relaxation rate of TRM for CoAl2O4 is indicated at low temperatures, which is probably related to the suppression of long-range antiferromagnetic order revealed by neutron diffraction studies.

It is proposed a processing route to obtain dense (≥90%) nanometric La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3− x (LSGM) electrolyte ceramic by reacting under spark-plasma-sintering (SPS) conditions a relatively poor mixture of intermediate powdered La/Sr- and Ga/Mg-based products synthesized separately by precipitation and hydrothermal methods, respectively. Samples with particle size of 9–20, 37–93, and 120–240 nm were measured from the electrical conductivity viewpoint. A fast transport path along grain boundaries was not observed and, a higher nano particle size improves total conductivity in our samples. Results suggest that it is necessary to make a clear distinction between particle size from microscopy observation and crystallite size from structural (e.g. XRD) measurements when looking at the general conductivity – grain size dependence. This dependence is complex and the use of an unconventional, far from equilibrium technique such as SPS might influence it. Currently, a good understanding is missing, but pending on materials, technology specifics and the complex relationship between them, some of the usually promoted ideas from literature such as the necessity of high mixing levels in the precursor powders, of high pressure application during sintering, of low particle size (nano) in the sintered ceramic for a higher conductivity, of high purity phase and so on require careful consideration.

Tri-axial orientation of twin-free powders of RE2Ba4Cu7O15-delta (RE247, RE = Y, Dy, Ho, Er) was attempted by modulated rotating magnetic fields. The c -axis orientation was almost completely achieved for all the four RE247 compounds, whereas the degrees of in-plane orientation depended on RE element. Especially for Y247, the degrees of in-plane and c-axis orientation were determined to be ~ 2.5degand < 2deg, respectively, by the phi-scanning and rocking curve measurements. This excellent in-plane orientation is comparable or superior to those for coated conductors ( ~ 4deg) and melt-solidified bulks ( ~ 8deg) of REBa2Cu3O7-delta. Magnetic field dependence of Lotgering factors revealed that the degrees of in-plane orientation were sensitive to the applied magnetic field. The required magnetic field for the tri-axial orientation is determined by the in-plane magnetic anisotropy rather than the magnetic anisotropy between in-plane and out-of-plane directions.

Easy axes of magnetization at room temperature in REBa2Cu3Oy (RE: rare earth) and Bi2Sr2Ca1-xRExCu2Oy were clarified using their powders oriented in a static magnetic field. The easy axes clearly depended on the type of RE which could be mainly explained in terms of second-order Stevens factors and magnetic anisotropy of the CuO2 plane. Furthermore, we found the difference in magnetic effects of Er3+ for orientation through systematic evaluations of Er-doped Y123 and Bi2212 powders. This result means that magnetic anisotropies of RE3+ ions are sensitive to not only the type of RE but also local structure of oxygen ions surrounding RE3+ ions.

Textured alumina ceramics were fabricated by electrophoretic deposition in a strong magnetic field of 10 T (Tesla) followed by sintering. Single crystalline α-alumina particles dispersed in aqueous media were aligned due to their anisotropic diamagnetic susceptibility and then deposited on a cathodic substrate. The degree of crystalline orientation of the as-deposited specimen characterized by X-ray diffraction was small but highly improved by sintering in the temperature range of 1273–1873 K. Microstructural observations showed the absence of any anisotropic grain growth.

In order to find a new energy-saving-powder manufacturing process, the pulverization due to hydrogenation of Nb-Zr-Fe alloys with 35 different compositions has been studied. The hydrogenation was performed under the hydrogen atmosphere of 0.1 MPa and room temperature in an arc melting chamber without exposure to air after arcmelting.Nb-Zr-Fe alloys absorb a large amount of hydrogen from 0.1 to 1.8 wt%H and pulverize into powders. This pulverization is closely related to the composition of alloys.The composition which is easy to pulverize is concentrated to the ranges of 15 at%Fe in Nb-Zr-Fe alloys and 15-30 at%Fe with fixed to Nb/Zr??1/1 in Nb-Zr-Fe alloys. For an example, hydrogen absorbed powder of 45Nb-40Zr-15Fe alloy has wide size distribution from 5 to 200 micron with flake figure and with many fine cracks.The hydrogen in powder of 45Nb-40Zr-15Fe alloy is stably stable until 473 K and dehydrogenation temperature is from 473 K to 773 K.It is estimated that hydrogenation is induced by proper amount of iron element in Nb-Zr-Fe alloys and a hydrogen rich phase and a hydrogen poor phase are formed in an alloy ingot. Forming of two phases by absorbing hydrogen causes to pulverization of Nb-Zr-Fe alloys.

Fe and composite Fe–TiN nanoparticles were prepared by an active plasma–metal reaction method. The structure and morphology were examined by X-ray diffraction, transmission electron microscopic observation and Mossbauer experiment. The morphology of Fe is spherical and that of the composite Fe–TiN nanoparticle is dumbbell-like. The surface oxide of the nanoparticles exposed to air was characterized and the reduction characteristics in a hydrogen atmosphere were examined. The thermal stability of the nanocomposite particle is vastly superior to that of the metal particle. The hydrogen sorption–desorption characteristics of the nanoparticles were examined by temperature-programmed desorption measurements. Hydrogen desorption at above 450 K was observed for the composite Fe–TiN nanoparticles. The effect of CO coadsorption on the hydrogen desorption was also examined and a large amount of hydrogen desorption was observed.

Silica-doped (SiO2 = 0 - 1.0 wt%) 3Y-TZP (3 mol % yttria-doped tetragonal zirconia polycrystal) ceramics are prepared from hetero-coagulated aqueous suspension by colloidal processing. Consolidation of the suspension was carried out by pressure filtration at 10 MPa followed by cold isostatic pressing (CIP) at 400 MPa. Consolidated compacts are densified to a relative density over 99% by sintering at 1573 K for 2 h. The formation of glass pockets at grain boundary multiple junctions was observed by SEM for ≥0.5 wt % silica-doped samples. Electrical conductivity measurements were performed to evaluate the modification of grain-boundaries by silica. The apparent grain boundary conductivity decreased with an increase in silica content and became nearly constant above 0.3 wt % of silica, while the bulk conductivity was constant with silica content.

Fine-grained monoclinic zirconia ceramic was made from well-dispersed zirconia sol prepared by the hydrolysis of zirconium chloride oxide octahydrate. Dechlorinated and concentrated zirconia sol was consolidated by pressure filtration. The relative green density of the compact was improved by the following cold isostatic pressing treatment at 400 MPa. The compact was densified by pressureless sintering to >98% of theoretical density in air at 1100 °C, which is lower than that of monoclinic to tetragonal transformation of pure zirconia. The average grain size of the sintered monoclinic zirconia ceramics was 92 nm.

Pressure filtration is applied to the consolidation of 3 mol% yttria-doped zirconia fine powder with average particle size of 60 nm over an applied pressure range of 2.5 to 10.0 MPa. Two kinds of aqueous suspension with different rheological behavior, well-dispersed and insufficiently dispersed, respectively, are prepared by changing the amount of dispersant. The kinetics and mechanics of the consolidation of particles are discussed from the dehydration and consolidation rates of the suspensions based on Darcy's law and the Kozeny-Carman equation. The consolidated layer prepared from the well-dispersed suspension shows a good sinterability. Cold isostatic pressing at 400 MPa increases the sintered density of the consolidated layer prepared from the insufficiently dispersed suspension.

Temperature and humidity dependence on electric conductivity is investigated for two kinds of antimonic acids, which have a cubic structure (c-SbA) and a monoclinic structure (m-SbA). The conductivity of m-SbA at 296 K is lower and more sensitive to humidity than that of c-SbA. The conductivity of c-SbA increases with increasing temperature, but, that of m-SbA decreases with increasing temperature under the saturated water vapor pressure in the temperature range of 296–353 K. FTIR measurements show the existence of motion-restricted water in m-SbA. The amount of adsorbed water in c-SbA is larger than that in m-SbA. The difference in conductivity between c-SbA and m-SbA is closely related to the state of hydroxyl groups and water molecules in both antimonic acids.

Aluminum (Al) and aluminum nitride (AlN) ultrafine powders (UFPs) were synthesized by an active plasma-metal reaction method. Temperature-programmed gas Desorption (TPD) measurements were conducted for the Al and/or AlN UFPs after exposure to air. H 2 O gas for AlN UFP, and H 2 O and H 2 gases for (Al + AlN) UFPs were mainly detected. The surface chemistry of the powders after exposure to air is estimated in comparison of the desorption characteristics with infrared spectrometry spectra. The evolved H 2 around 420 °C from the (Al + AlN) UFPs is due to the reaction of H 2 O with inner Al. The evolved H 2 O is considered to be formed by the reaction of adsorbed H 2 O on surface oxide of the powders and decomposition of hydroxide-like compounds.

The surface oxide layer of fine nickel particles has been investigated by high- resolution electron microscopic observation,, electron diffraction, X-ray diffraction, X-ray photo- electron spectroscopy and temperature-programmed gas desorption experiment. The thickness of the oxide layer formed on the particles was about 2 nm. The oxide layer was composed of innermost NiO, and outermost Ni(OH)2 and amorphous nickel carbonate-hydroxide. The oxide layer give a good thermal stability to fine nickel particles.

Sintering characteristics of three kinds of iron and FeCo alloy ultrafine powders (UFPs) in vacuum and a hydrogen atmosphere were examined by continuously measuring their dimensions, and observing their structural changes. The UFPs exposed to air contain mixtures of oxide and hydroxide phases. The oxide phase increased during heating in vacuum. The compacts of the UFPs shrunk slightly at temperatures between 450 and 700 K, where the surface oxides sintered, and then densified rapidly above 700 K. The shrinkage in a stream of hydrogen occurred at much lower temperatures than that in vacuum. The reduction reaction is ratecontrolled by an interface reaction and the reduction rate of the UFPs depends on the oxidation level, where the more highly oxidized UFPs tend to the lower reduction rate. Activation energies of the reduction rate constants of the iron UFPs and FeCo UFPs lie in the range 48–59 kJ mol−1.

A 59-year-old male clerk consulted in general practitioner due to cough and hemoptysis. A mass shadow was pointed out in the left upper lung field on a chest radiograph. Patient was referred to our hospital for further treatment. Any definitive daiagnosis could not be made after examinations including sputum culture, cytology and TBLB. Because a lung cancer was strongly suspected, an exploratory thoracotomy was performed. Actinomyces was detected by pathological study of excised specimen, with no evidence of cancer. ABPC was administered for two months postoperatively. The patient is doing well without recurrence of actinomycosis 2.5 years after the surgery. Pulmonary actinomycosis presenting a mass shadow on a radiograph may mimick a pulmonary tumor, especially a lung cancer. Pulmonary actinomycosis should be considered in a differential diagnosis of pulmonary lesion thought to be malignant.

The clinicopathological features of veno-occlusive lesions (VOL) in the liver were studied in 18 autopsy cases of severe alcoholic hepatitis (sALH). All the cases were heavy drinkers and died of liver failure or variceal rupture.We performed histological evaluation by examining stained sections of liver blocks from each case. The severity of VOL was compared with the clinical findings and histopathological changes of alcoholic liver diseases (ALD).Clinically, as the severity of VOL increased, the amount of ascites observed during autopsy increased significantly (p = 0.001) and the time from hospitalization to death was significantly longer (p0.05). The peripheral leukocyte count tended to increase and the serum bilirubin level increased significantly (p0.05) with increased VOL severity, after we excluded one case that was complicated by acute respiratory distress syndrome and bacterial endocarditis. Histopathologically, the appearance of Mallory bodies increased significantly as VOL became more severe (p0.05), but the VOL severity did not correlate with sinusoidal neutrophil infiltration. Fatty degeneration tended to be milder as VOL increased in severity although the difference was not significant, whereas bile retention tended to be more marked.We conclude that investigation of VOL is clinicopathologically important when assessing the pathophysiology and severity of sALH.

Mallory bodies, the intra-cytoplasmic inclusions in hepatocytes, are thought to be a pathognomonic feature of alcoholic liver disease, particularly of alcoholic hepatitis. The presence of Mallory bodies is considered as a reflection of serious illness in alcoholic liver disease. Mallory bodies are thought to disappear relatively rapidly with the use of therapeutic agents after giving up alcohol drinking. However, histological vicissitudes of Mallory bodies have not been studied extensively. In the present study, 19 autopsied cases with a history of heavy drinking were clinicopathologically evaluated. All patients were admitted to our hospital, and stopped alcohol drinking. These period of non-drinking ranged from one day to 150 days (group A: 1-7 days, group B: 8-30 days, group C: 31-150 days). Histological evaluation was performed by hematoxylin and eosin staining, Luxol Fast blue staining and chromotrope aniline blue staining of formalin-fixed paraffin-embedded liver sections. Hepatocytes including Mallory bodies were counted. The incidence of Mallory body formation was as follows: Group A (50%), group B (100%), and group C (100%) respectively. Average count of Mallory bodies: Group A (12.3/10 fields), group B (141.4/10 fields), and group C (188.3/10 fields). Fatty change was more significant in group A than in group B or C, and bile stasis was more significant in group B or C than in group A. These findings suggest that Mallory bodies may remain for several months after giving up drinking.

Fabrication of fine-grained monoclinic zirconia ceramics has been attempted from acid and neutral zirconia sols, which have been prepared by different methods. Complete re-dispersion of flocculated particles for the neutral sol is impossible even by changing its pH, while no flocculation is observed for the acid sol. Chloride ions, which are inevitably present in the acid sol, are removed effectively by using anion exchange resin. Consolidation of the sols is performed by the pressure filtration method at 10 MPa, followed by CIP treatment at 400 MPa. It is possible to densify the compacts from both sols to >98% of theoretical density by pressureless sintering in air at 1100 °C. This temperature is lower than that for the monoclinic to tetragonal transformation of pure zirconia. Fine and homogenous-grained microstructures, which have an average grain size of 92 nm, are observed for monoclinic zirconia fabricated from the acid sol. However, more coarse and heterogeneous microstructures are observed for the compact fabricated from the neutral sol.

Powders and films of amorphous, cubic and monoclinic antimonic acids are prepared. Their water sorptioh isotherms and the water desorption spectra are measured. The protonie conductivities are very sensitive to water vapor pressure and are discussed with the amount of water. The amorphous and cubic antimonic acids contain larger amounts of water than the monoclinic acid, which can be attributed to the existence of micropores in the structures.

Liver histology was compared in patients with chronic hepatitis C to clarify the difference between responders and non-responders to interferon therapy. We have treated 50 patients with chronic hepatitis C by natural IFN-alpha 6.0 MU/day for 2 weeks, daily, followed by intermittent therapy for 3-6 months. The overall effect of IFN was a complete response (CR) in 16 (32%), transient response (TR) in 14 (28%), and no response (NR) in 20 (40%). According to the pre-treatment liver histology, CR had a lower total numerical scores than TR and NR. Histological difference between CR and TR appeared to be the degree of portal inflammation and piecemeal necrosis, though NR showed an increase in portal fibrosis compared of CR and also TR. Response to IFN may depend on the degree of liver fibrosis rather than other histological factors. To assess the degree of liver fibrosis is thought to be important for the prediction of the efficacy of IFN therapy.

ANbO3 – BaTiO3 (A = K, Na, or K0.5Na0.5) system ceramics were prepared using a conventional sintering method, and their dielectric properties were investigated. It was found that the dielectric constant of KNbO3-BaTiO3 system ceramics did not strongly depend on temperature between 20 and 400 °C, making them useful for capacitor application. However, the dielectric constant of KNbO3-BaTiO3 system ceramics was low. The high dielectric constant is attributable to a large area of interfaces between KN and BT grains. Ceramics sintered by spark plasma sintering (SPS) are expected to suppress a grain growth, increasing area of the interfacial layer. In this study, SPS method was employed to achieve a large area of the interfaces and to see how the dielectric properties change with the interfacial structure. The structure was controlled by changing sintering temperatures and time of the spark plasma sintering. As a result, X-ray diffraction patterns showed that perovskite single phase and their relative densities were greater than 97%. By contrast, the dielectric constant was decreased.

We investigated the synergistic efficacy of CDDP and UFT, an oral anticancer derivative of 5-fluorouracil, on DNA synthesis of 3'-MeDAB-induced hepatocarcinomas in rats. Chronic treatment with CDDP slightly reduced tissue activities of thymidylate synthetase and thymidine kinase in the hepatocarcinomas, and, moreover, simultaneous administration of a low dose of UFT with CDDP markedly suppressed both enzyme activities, i.e., UFT and CDDP showed a potent synergism on DNA synthesis in hepatocarcinomas.

We report the development of a new high oxygen pressure synthesis method of orthorhombic and twin-free RE2Ba4Cu7Oy (RE247, RE = rare earth elements) superconductors and their tri-axial orientation using by a modulated rotation magnetic field. By the new synthesis method using quartz ampoule and a chemical reaction generating additional source of oxygen pressure in it, we have successfully fabricated RE247 (RE=Y, Er) polycrystals in the almost same synthesis conditions with those using a high oxygen pressure furnace. Furthermore, tri-axial orientation of these RE247 powders has been successfully accomplished using a modulated rotation magnetic field. Although our experimental studies on the magnetic orientation were performed in epoxy resin, high degrees of in-plane orientation less than 6° were achieved. Especially for RE=Y, the degree of in-plane orientation was found to be less than 1.5°, and high effectiveness of this tri-axial orientation technique was shown in principle.

Inhibitory effect of UFT on hepatocarcinogenesis in rats induced by 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB) and phenobarbital (PB) promotion was studied. Donryu male rats were divided into four groups. Group A was fed a diet containing 0.06% 3'-MeDAB for 3, 5, or 7 weeks, and then fed normal diet for 2 weeks, subsequently received a diet containing 0.05% PB. Group B was given UFT (20 mg/kg/5 days a week) simultaneously with feeding 3'-MeDAB. Group C was given UFT simultaneously with feeding PB. Group D was given 3'-MeDAB alone. In all groups, the development of hepatocellular carcinoma was investigated 37 weeks later and the number and area per mm2 of induced glutathione S-transferase placental form (GST-P) positive foci were measured using an image processor. The number and area of GST-P positive foci in group B and group C were markedly decreased as compared with those in group A. These results seem to show that the administration of UFT inhibited the production of GST-P positive foci and that stronger inhibitory effect of UFT was observed by simultaneous administration of an initiator than by that of a promoter.

The adsorption of hydrogen on Ni and NiTiO 2 composite ultrafine particles (UFPs) was studied by temperature-programmed desorption (TPD) experiments. The desorption characteristics of hydrogen on Ni and NiTiO 2 composite UFPs were similar to those of a Ni single crystal or polycrystal. The amount of adsorption of hydrogen on NiTiO 2 composite UFPs was dependent upon the temperature of exposure, and the phenomenon attributed to the spillover of hydrogen from Ni onto TiO 2 . The CO hydrogenation reaction on NiTiO 2 composite UFPs proceeded above 373 K. TPD spectra showed new desorption peaks after the catalytic reaction above 373 K and suggested the formation of new adsorption states.

Protonic conductivities of cubic and monoclinic antimonic acids are known to depend on water vapor pressure. Their water sorption-desorption characteristics are compared and discussed with the water sorption isotherms and the desorption spectra of H{sub 2}{sup 16}O, D{sub 2}O, and H{sub 2}{sup 18}O. The cubic antimonic acid contains more water than the monoclinic acid, which can be attributed to the existence of micropores in the cubic (pyrochlore type) structure.

Ni-TiN nanocomposite particles are prepared by RF plasma. Dumbbell-like and dice-like morphologies are seen. Hydrogen sorption-desorption characteristics of the nanocomposite particles were examined by temperature-programmed desorption measurements. Hydrogen desorption at 500–700 K is observed, which implies that a new adsorption state of hydrogen exists. Hydrogen desorption characteristics are not so influenced by coadsorption of CO. The results are compared with the previously reported ones that were produced by a DC plasma reaction method.

Silica-doped (SiO2= 0–1.0 mass%) zirconia (3 mol% Y2O3-doped tetragonal ZrO2) compacts are prepared from hetero-coagulated and well-dispersed suspensions by colloidal processing. The suspensions are consolidated by a pressure filtration technique. The green density of the compacts consolidated from the well-dispersed suspensions is higher than that from the hetero-coagulated suspensions. The lower density of the latter compacts is improved by a subsequent cold isostatic pressing (CIP) at 400 MPa. The sinterability of the compacts at 1200 °C is greatly affected by the amount of doped silica. The densification and grain growth are hindered by silica doping above 0.3 wt% at 1200 °C. All the compacts are densificated to a relative density of above 99% by sintering at 1300 °C for 2 h.