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Photoemission and inverse-photoemission spectroscopy (PES and IPES) measurements were carried out on amorphous Mg85Zn6Y9 alloy together with the polycrystal of the same concentrations with a synchronized long-period stacking ordered phase to investigate the valence- and conduction-band electronic structures, respectively. The valence- and conduction-band density of states (DOS) seems to be mostly the same as that of the crystalline phase. The core-level PES measurements were also performed at the Mg 2s, 2p, Zn 3p, 3d, and Y 3d levels to study the chemical natures of the constituent elements. The Y 3d core spectrum exhibits mostly three doublets in the amorphous phase, while mostly only one in the crystalline phase. This result reflects a coexistence of three different sites of the Y atoms in the amorphous phase; ones in the Zn6Y8 L12 clusters or their large fragments of about 57%, ones in their small fragments of about 20%, and isolated atoms of about 23%, which are mostly the same as those in the Mg97Zn1Y2 lightly doped LPSO alloy. Thus, it is concluded that well-fledged seeds of the L12 clusters are already provided even in the amorphous phase.

Background: Since stroke patients with nonvalvular atrial fibrillation (NVAF) have poor outcomes in general, the prediction of outcomes following discharge is of utmost concern for these patients. We previously reported that brain natriuretic peptide (BNP) levels were significantly higher in NVAF patients with larger infarcts, higher modified Rankin Scale (mRS) score, and higher CHADS2 score. In the present study, we evaluated an array of variables, including BNP, in order to determine significant predictors for functional outcome in patients with NVAF after acute ischemic stroke (AIS). Methods: A total of 615 consecutive patients with AIS within 48 h of symptom onset, admitted to our hospital between April 2010 and October 2015, were retrospectively searched. Among these patients, we enrolled consecutive patients with NVAF. We evaluated the mRS score 3 months after onset of stroke and investigated associations between mRS score and the following clinical and echocardiographic variables. Categorical variables included male sex, current smoking, alcohol intake, hypertension, diabetes mellitus, dyslipidemia, coronary artery disease, peripheral artery disease, use of antiplatelet drugs, anticoagulants, or tissue plasminogen activator (tPA), and infarct size. Continuous variables included age, systolic blood pressure (SBP), diastolic blood pressure, hemoglobin, creatinine, D-dimer, brain natriuretic peptide (BNP), left atrial diameter, left ventricular ejection fraction (EF), and early mitral inflow velocity/diastolic mitral annular velocity (E/e’). We also analyzed the association of prestroke CHADS2, CHA2DS2-VASc, and R2CHADS2 scores, and National Institutes of Health Stroke Scale (NIHSS) score on admission with mRS score 3 months after the onset of stroke. Patients were classified into 2 groups according to mRS score: an mRS score ≤2 was defined as good outcome, an mRS score ≥3 was defined as poor outcome. To clarify the correlations between categorical or continuous variables and mRS score, uni- and multivariate logistic regression models using the stepwise variable selection method were applied. Results: Among 157 patients with NVAF after AIS, 63.7% were male and the mean age was 75.9 years. In univariate regression analysis, poor outcome (mRS score ≥3) was associated with use of tPA, infarct size, age, SBP, BNP, EF, and NIHSS score. In multivariate regression analysis, BNP levels (odds ratio [OR] 6.40; 95% confidence interval [CI] 1.26–32.43; p = 0.0235) and NIHSS score (OR 2.87; 95% CI 1.84–4.47; p < 0.001) were significantly associated with poor outcome (mRS score ≥3) after adjusting for use of tPA, infarct size, age, BNP, EF, and NIHSS score. Conclusions: Apart from NIHSS score, BNP was a very useful predictor for long-term outcomes of patients with NVAF after AIS.

Local structures of ${\mathrm{Pd}}_{40}{\mathrm{Ni}}_{40}{\mathrm{P}}_{20}$ bulk metallic glass were investigated by combining anomalous x-ray scattering close to the Pd and Ni $K$ absorption edges, x-ray diffraction, neutron diffraction, and reverse Monte Carlo modeling, from which partial structure factors ${S}_{ij}(Q)$ and partial pair distribution functions ${g}_{ij}(r)$ as well as three-dimensional atomic configurations were carefully obtained around the constituent elements. A disagreement is found in the local structures with an ab initio molecular dynamics simulation by Guan et al., i.e., the existence of the P-P nearest-neighboring configurations is clarified in the present experimental result. From the Voronoi tessellation analysis, a preference of the pure icosahedral configurations is observed around the Ni atoms, whereas the local configurations around the Pd and P atoms are rather distorted icosahedra. A persistent homology analysis was carried out to identify meaningful shape characteristics of the intermediate-range atomic configuration of large rings.

The metal-to-insulator transition and the presence of the disorder induced localization of electronic orbitals of fluid mercury (f-Hg) were investigated. The electronic structure of f-Hg was simulated by using the ab initio molecular dynamics. To determine the simulation size dependency of the electronic orbital, the electronic orbitals of systems with different number of atoms were investigated. The multifractal measure was used for analyzing the localization of the electronic orbitals and the size dependency of that reversed during the decrease of the density, which suggests there exists the extended-to-localized transition near the metal-to-insulator transition region of f-Hg.

Background Non-vitamin K antagonist oral anticoagulants (NOACs) show a favorable balance between efficacy and safety compared with warfarin for patients with non-valvular atrial fibrillation (NVAF). In “real-world” practice, however, NOAC adherence and persistence among patients are not clear. The aim of this study is to evaluate NOAC and warfarin persistence in Japanese patients with NVAF who newly started these drugs. Methods We retrospectively studied 401 patients with NVAF who had newly started NOACs during the first 18 months after our hospital adopted their use (197 dabigatran, 107 rivaroxaban, 102 apixaban) and 200 patients with NVAF who had newly started warfarin during the same period. The endpoint was drug discontinuation for each drug. Results During the follow-up period (up to a maximum of 24 months), 113 (28%) patients who had newly started NOACs and 33 (17%) patients who had newly started warfarin discontinued the drug. The persistence rates of patients prescribed NOACs was lower than that of patients prescribed warfarin at 3, 6, and 12 months (85% versus 93%, 79% versus 88%, and 70% versus 82%, respectively). One-tenth of patients who had newly started NOACs discontinued the drug by their own decision. Drug adverse events, worsening renal dysfunction, and patient desire were the major causes of NOAC discontinuation. Conclusions The rate of persistence of prescribed NOACs was significantly lower than that of warfarin in Japanese patients with NVAF.

Background: Drug adherence decreased in patients with Parkinson' s disease (PD) because of tak- ing many different types of drugs. We evaluated drug adherence after switching from imme- diate-release (IR) to once-daily extended-release (ER) pramipexole (PPX) in PD. Methods: This study included 35 PD patients (20 men, 15 women); 10 were taking oral PPX alone, and 25 were also using another anti-PD drug. PPX-IR was switched overnight to PPX-ER without gradual taper- ing. One month after switching, improvement in timing adherence and reduction in medication burden were evaluated by a questionnaire using a visual analog scale (VAS) (0: No change; 10: Better). Motor function was assessed using part III of the Unified Parkinson's Disease Rating Scale (UPDRS). Results: The VAS score for improvement in timing adherence was 8.1 ± 0.5 (mean ± standard error), and that for reduction in medication burden was 7.3 ± 0.6. There was a significant negative correlation (ρ = −0.43, p = 0.01) between the VAS score and number of types of medica- tions. The UPDRS part III score improved significantly after switching (p < 0.01). Only one patient discontinued PPX-ER after switching. Conclusion: Switching from PPX-IR to once-daily PPX-ER is safe and improves motor function in patients by improving timing adherence and reducing medi- cation burden.

Background and Purpose— Paroxysmal atrial fibrillation (PAF) is often difficult to detect in patients with acute ischemic stroke. We aimed to assess the predictive value of a prolonged QT interval corrected for heart rate (QTc) in PAF detection after acute ischemic stroke. Methods— We enrolled 972 patients with acute ischemic stroke consecutively extracted from our observational stroke registry system. Exclusion criteria were as follows: (1) AF on the initial 12-lead ECG (n=171); (2) previously diagnosed PAF (n=47); and (3) the use of a cardiac pacemaker (n=10). Of the 972 patients, 744 (mean age, 67.6 years; men, 62.6%) were eligible for analysis. The clinical characteristics and 12-lead ECG findings of the patients with and without PAF were compared, and multiple logistic regression analysis was performed to identify predictors of poststroke PAF. Results— The poststroke cardiac work-up yielded 69 (9.3%) de novo PAF cases among the 744 patients. The QTc interval was significantly longer in patients with PAF than in those without PAF (436 versus 417 ms; P P Conclusions— The QTc interval prolongation is potentially a strong and useful predictor for poststroke PAF.

A tsunami-induced difference between the water levels of the seaward and the landward sides of breakwaters generates one-way seepage in the rubble foundation under the breakwaters. Such seepage may decrease the bearing capacity of the rubble foundation, trigger the piping and/or boiling of the foundation, and cause the scouring of the sandy seabed. In this paper, we describe the stability of a breakwater foundation under the action of seepage based on the results of model tests and FEM analyses. The main feature of our study is the application of the centrifuge technique to such composite hydrodynamic and geotechnical problems. The centrifuge technique can be used to produce high-water pressure and ground stress corresponding to those of prototype-scale breakwaters. The experimental results show that seepage-induced scouring and boiling occur, and that the seepage force decreases the bearing capacity of the rubble foundation. The results of the numerical analyses also reveal the effect of the reduction in bearing capacity in the presence of seepage.

The Dollarbird (Eurystomus orientalis) is a secondary cavity-nesting bird that is distributed quite locally in Japan. We carried out extensive surveys across Okayama Prefecture to estimate the number of pairs and found that the major breeding site was holes excavated by woodpeckers in wooden electricity and telegraph poles. Wooden poles were abundant until the 1970s, but most were replaced by concrete poles in the 1980s. Removal of wooden poles containing cavities seriously threatened the breeding population over the first half of the 1990s. In an effort to preserve the Dollarbird population in Japan, beginning in 1991 we provided nestboxes in the village of Kibi (Okayama Prefecture). This resulted in only a small increase in population size over the following 5 yr, but between 1996 and 2001 there was a large annual increase in the breeding population. Increase then leveled off after 2002. Population increase showed a time lag following increase in number of available boxes. Finding new nestboxes may take some time, initially resulting in a low occupation rate for some years after start of box provisioning. Finding of nestboxes by pairs that had bred near Kibi and their subsequent reproduction may have led to a sharp population increase between 1995 and 2002. On the other hand, leveling off of increase in Dollarbird breeding pairs after 2003 may have been directly derived from leveling off of increase in available nestboxes. This suggests a maximum nestbox occupancy rate of 70%–80% in Kibi.

Elevated serum brain natriuretic peptide (BNP) levels are associated with cardioembolic stroke mainly because of atrial fibrillation (AF). However, the mechanisms of increased serum BNP levels are hitherto unclear. We aimed to identify the factors associated with increased BNP levels in patients with acute ischemic stroke. We measured serum BNP levels in consecutive patients aged 18 years or older. Stroke subtypes were classified using the Trial of ORG 10172 in Acute Stroke Treatment criteria. Categorical variables included age, sex, smoking status, alcohol consumption status, hypertension, diabetes mellitus, dyslipidemia, coronary artery disease (CAD), AF, antiplatelet therapy, and anticoagulant therapy. Continuous variables included hemoglobin, creatinine (Cr), β-thromboglobulin, platelet factor 4, thrombin–antithrombin complex, and d-dimer levels. We further determined the relationship between serum BNP and intima–media thickness, left ventricular ejection fraction, size of infarction, National Institutes of Health Stroke Scale score on admission, and modified Rankin Scale (mRS) score at discharge. Of the 231 patients (mean age, 71 ± 12 years) with acute ischemic stroke (AIS), 36% were women. Serum BNP levels significantly correlated with CAD, AF, Cr, mRS, and cardioembolism (CE) (Dunnett method, P = .004). BNP levels were significantly higher in patients with larger infarcts, higher mRS scores, and higher CHADS 2 scores. The levels were higher in patients with larger infarcts, higher mRS scores at discharge, and higher CHADS 2 scores among AF patients.

The reverse Monte Carlo (RMC) and Voronoi-Delaunay (VD) void analyses were applied to study the modification of chain geometries near the semiconductor (SC) to metal (M) transition in expanded liquid Se along the isochore of d = 3.4 g/cm3 .Fluctuations of dihedral angles with increasing temperature and pressure cause modification of the helical (H) chain to the planar zigzag (Z) chain conformations. The distribution of voids size (rV ) supported by chain segments and distances to the 4th ~ 6th neighbor atoms on the chain segments provide information on the stacking of planar zigzag chains compensated by empty space (L-voids, rV ~ 3.6 A) which leads to the formation of metallic domains. Near SC-M transition region the number fraction NZ /NH for Z and H chain segments increases.

Brachial-ankle pulse wave velocity (baPWV) is a good measure of arterial stiffness and is associated with risk of future vascular events. The present study aimed to examine whether baPWV can also predict 3-month functional outcome after stroke.This hospital-based study included 327 consecutive patients with acute ischemic stroke and in whom baPWV was measured during hospitalization. We defined good and poor functional outcomes as a modified Rankin Scale score of3 and ≥ 3 at 3 months, respectively, after initial stroke.Patients with poor outcomes were significantly older (73.1 versus 66.3 years, p 0.001) and more likely to have extracranial carotid arterial stenosis (29.5% versus 13.1%, p 0.001), atrial fibrillation (21.0% versus 11.3%, p = 0.020), history of coronary artery disease (20.0% versus 11.7%, p = 0.042), and high baPWV value (22.84 versus 19.48 m/s, p 0.001). Irrespective of patients' age, sex, baseline risk factors, initial stroke severity, and stroke etiology, baPWV was consistently higher in patients with poor outcome than those with good outcome. Multivariate analysis revealed that baPWV23.11 m/s, calculated from the receiver-operating characteristic curve, had an independent predictive value for poor functional outcome (odds ratio, 1.51; 95% confidence interval, 1.08-2.11; p = 0.016).BaPWV measured during the acute phase of stroke can independently predict 3-month functional prognosis. We suggest that baPWV should be performed as part of the early stroke work-up to identify patients suffering from severe stroke-related disability.

Anomalous X-ray scattering experiments were performed on Zr63Ni25Al12 bulk metallic glass. The results were analyzed using reverse Monte Carlo modeling to obtain local- and intermediate-range atomic configurations of this good metallic glass former. Although the Al-related partial information is not reliable due to the small values of their weighting factors in X-ray scattering, good partial information could be obtained from a reverse Monte Carlo analysis. The obtained structural information is given by parameters such as bond angle distributions, bond orientation order parameters, the Warren–Cowley order parameters, and Voronoi polyhedra. Results are compared to the previous results from Fukunaga et al. using X-ray and neutron total scattering.

Adenoid cystic carcinoma (ACC) is a malignant neoplasm that commonly arises in the major or minor salivary gland and usually forms mass lesions. Here, we report a case of ACC involving a 56-year-old man, who displayed right multiple cranial nerve palsies with ipsilateral severe facial pain but not any mass formation. Right submaxillary gland biopsy after repeated challenges at last revealed the primary focus of ACC with perineural invasion and without lymph node metastasis. The neurological manifestations were considered to be attributed to the perineural spread of ACC. It is extremely rare for ACC to show Garcin's syndrome without mass formation.

軟弱粘土層上に重力式岸壁を整備する場合，安定性向上ために締固め砂杭工法（SCP工法）が多く利用されている。本研究では，改良材として天然の砂質土の代わりに固結特性を有する鉄鋼スラグを用いた地盤の安定性について，遠心模型実験および円弧滑り計算によって検討した。模型実験では，比較対象として鉄鋼スラグ以外に砂質土等で改良した粘土層に対しても遠心力場で埋立載荷した。その結果，砂質土および鉄鋼スラグによる改良地盤が破壊に至る変形モードは一致した。また，砂質土よりも鉄鋼スラグで改良を施した地盤の方が載荷によって生じる変形量が小さく，安定性も高いことが分かった。

Metal-ferroelectric-insulator-Si (MFIS) structures using HfSiON as buffer layers were fabricated, and the impact of buffer layer thickness on the electrical properties of the MFIS devices was investigated. HfSiON films with thickness ranging from 1 to 4 nm were deposited by electron beam evaporation, which exhibited much reduced leakage current when compared to that of SiO2 with the same equivalent oxide thickness. From the viewpoint of polarization and charge injection, the flatband voltage and memory window width dependent on the sweeping voltages were discussed for the MFIS diodes with 1-, 2-, and 4-nm-thick HfSiON buffer layers. Small leakage current as well as excellent long-term data retention characteristics were found for all of these samples. It was also found that MFIS diodes with 2-nm-thick HfSiON buffer layer have the largest memory window width. Ferroelectric-gate transistors fabricated with a Pt/SBT(300nm)/HfSiON (2 nm)/Si gate structure showed a memory window of 0.8 V and a high drain current on/off ratio of 108 for the gate voltage sweep between +4 and −4 V. All of these excellent electrical properties proved that HfSiON acts as an excellent barrier for suppressing both leakage current and atomic interdiffusion.

Single phase BiFeO3 (BFO) thin films were fabricated by chemical solution deposition on Pt/Ti/SiO2/Si(100) structures. J-E (current density vs. electric field) and P-V (polarization vs. voltage) characteristics were measured at room temperature (RT). It is shown in J-E characteristics that sharp increase in the current density occurs at a lower electric field in a thinner BFO film. The P-V hysteresis loops were measured by changing frequencies with triangular voltage pulses from 1 to 100 kHz. The remanent polarization decreases with the frequency mainly between 1 and 20 kHz and the decrease was significant less at higher frequency. The decrease of polarization in the hysteresis loops corresponds to the leakage current components. Furthermore, the coercive field was virtually independent of the measurement frequency. It is concluded from these results that the large remanent polarizations measured in BFO films at RT are intrinsic ones based on ferroelectricity of the films.

In this work, metal-ferroelectric-insulator-silicon (MFIS) devices were fabricated using HfSiON as buffer layers and their electrical properties were studied. Ultra-thin HfSiON films were fabricated by electron-beam evaporation at room temperature and post-annealed using different parameters such as temperature, time in O2. By annealing a 2 nm-thick HfSiON film at 800°C for 60s in O2, a negligible hysteresis loop and small equivalent oxide thickness of 2.3 nm were obtained with a corresponding leakage current density of 6.8 × 10− 5 A/cm2 at a voltage shifted from the flat band voltage by 1 V. In the fabrication of MFIS diodes, Sr0.8Bi2.2Ta2O9 (SBT) films with 400 nm thickness were formed by chemical solution deposition. For Pt/SBT (400 nm)/HfSiON(2 nm)/Si diodes, a memory window of 0.8 V in width was observed during double capacitance-voltage sweep between +5 and –5 V. At the same time, excellent data retention properties were observed. The high and low capacitances in the hysteresis loop were we...

Ferroelectric properties and fatigue endurance of 5% Mn-substituted BiFeO3 (BFO) films deposited on iridium (Ir) and platinum (Pt) electrodes have been discussed. 5% Mn-substituted BFO thin films have been formed on Ir/Ti/SiO2/Si(100) and Pt/Ti/SiO2/Si(100) substrates by chemical solution deposition (CSD). X-ray diffraction patterns have proved that BFO films on both Ir and Pt electrodes have distorted rhombohedral R3c structure. It has been found in electrical measurements that leakage current density in the BFO films on Ir electrodes is higher than that in the film on Pt electrode, which is probably due to the lower Schottky barrier height of Ir than Pt. The maximum remanent polarization (Pr) and the minimum coercive electric field in BFO films on Ir electrodes were 82 µC/cm2 and 0.3 MV/cm, respectively, at an applied electric field of 2 MV/cm and a measurement frequency of 10 kHz. It has also been found that decrease of the annealing temperature to 525 °C is effective to improve the fatigue endurance.

Two cases (a 33-year-old woman and a 34-year-old man) were diagnosed as having cerebral tuberculosis. Case 1 was tuberculoma with miliary tuberculosis complicating cranial nerve palsies, and case 2 was tuberculous meningitis. Early diagnosis was difficult, because smear and PCR were negative. Culture was finally positive after several weeks. QuantiFERON were positive prior to the culture results in both cases. This reaction suggested tuberculous infection. QuantiFERON is useful for diagnosing cerebral tuberculosis at an early stage.

The Deep Mixing Method, an in-situ soil stabilization technique using cement and/or lime, is often applied to improve soft soils. The group column type improvement is extensively applied to stabilize foundations of embankment or lightweight structures. The improved ground design procedure in Japan assumes two failure patterns related to external and internal stabilities. External stability is evaluated for the possibility of sliding failure, in which DM columns and clay between show horizontal displacement on a stiff layer without any rearrangement of columns. For internal stability, the possibility of rupture breaking failure is evaluated by slip circle analysis, assuming the shear failure mode of DM columns. In this study, a series of centrifuge model tests was carried out to investigate the internal stability of improved ground under embankment loading. This paper describes the failure modes of DM columns and a proposed simple calculation that takes into account the bending failure mode.

In the liquid Rb–Se mixture there exists a liquid–liquid phase separation (miscibility gap) in the Se-rich concentration region. In order to study how the local structure is associated with the occurrence of the miscibility gap, EXAFS and neutron diffraction measurements for liquid Se, Rb 10 Se 90 , Rb 15 Se 85 and Rb 20 Se 80 mixtures have been carried out. The results reveal that the interaction between Rb and Se atoms is very weak and the liquid mixtures are composed of short Se chain-molecules of which chain ends are terminated by Rb atoms. We have carried out detailed structural modeling studies using reverse Monte Carlo simulation. It is found that the chain-like or ring-like Se segments are separated by voids. The Rb atoms adsorbed to Se chain ends segregate in the void and the shortened Se chain-molecules link up with each other when one approaches the miscibility gap.

The applicability of sol–gel process in glass formation of binary system, (100 − x)TiO2–xNa2O (x = 10, 20, 30), was investigated and the glasses were prepared successfully by the sol–gel process for the first time. The process of glass formation was checked by using X-ray diffraction measurement and DTA–TG analysis. In the baking step, a DTA peak related to the crystallization of gel was found. The short-range structure of glassified samples was studied by neutron scattering measurement. It is found from the results of neutron scattering measurement that the coordination number of O atom around Ti atom is about 4, and the O atoms around Ti atom form a planer square rather than a regular tetrahedron.

In this study, BiFeO3 (BFO) epitaxial film was deposited on SrRuO3(100)/SrTiO3(100) substrates by pulsed laser deposition (PLD). Phase-pure BFO thin film was obtained by introducing a mask between the target and the substrate in the deposition chamber. The use of the mask brought about an improvement in the morphology. The surface roughness was changed from 47.8 to 7.7 nm rms roughness under conditions without and with the mask, respectively. The composition and the electrical properties of BFO thin films were examined before and after annealing the samples for 1 h in atmospheric pressure O2 gas at 600 °C. An improvement of the polarization–electric field (P–E) hysteresis curve was obtained when BFO film was annealed in an O2 atmosphere. O2 gas annealing resulted in a remanent polarization (Pr) value increase from 17 to 25 µC/cm2 at room temperature. At a low temperature (80 K), the BFO thin film annealed in an O2 atmosphere showed the highest Pr of 142 µC/cm2. We also investigated the optimum measurement conditions of the P–E hysteresis curve for BiFeO3.

The Deep Mixing Method (DMM), a deep in-situ soil stabilization technique using cement and/or lime as a binder has been often applied to improve soft soils. Group column type improvement has been extensively applied to foundations of embankment or lightweight structures. A design procedure for the group column type DM ground has been established in Japan mainly for application of embankment, in which two failure patterns are assumed: sliding failure in the external stability and rupture breaking failure in the internal stability. The internal stability of the improved ground has been investigated experimentally, and it was found that the DM columns show various failure modes: shear, bending and tensile failure, depending not only on the ground and loading conditions but also on the location of each column. However, the current design does not incorporate the effects of these failure modes, but only that of shear failure mode. For the external stability, it is known that a collapse failure pattern, in which the DM columns tilt like dominos, could take place instead of sliding failure. The current design method, which does not take into account this failure pattern, might overestimate the external stability. In this study, a series of centrifuge model tests and elasto-plastic FEM analyses were performed to investigate the external stability of group column type DM improved ground under embankment loading. The centrifuge model study has revealed that the improved ground does not fail with a sliding failure pattern but with a collapse failure pattern in the model test condition. The FEM analyses confirmed the model test results and showed that the improved ground could fail with sliding failure in a certain type of ground conditions such as a floating type improved ground. A simple calculation incorporating the collapse failure pattern gave reasonable estimation of the embankment pressure at ground failure. This paper demonstrates the importance of simulating appropriate failure pattern for evaluating the external stability accurately.

Neutron diffraction measurements of the liquid Ge–Te system and quasi- and inelastic neutron scattering experiments of the eutectic liquid Ge 15 Te 85 were performed in the temperature range from 400 to 560 °C. The large temperature dependence of the static structure for liquid Ge 15 Te 85 is reconfirmed; however it is found that the compositional dependence obtained at around 80 °C above the liquidus curve is rather small. The dynamic structure factors of liquid Ge 15 Te 85 in the Q -region from 0.2 to 2.6 A −1 show a normal temperature dependence. From the vibrational density of states, it is found that the Te–Te covalent bond persists in liquid Ge 15 Te 85 ; however a bending mode was not assigned clearly.

La-substituted BiFeO3 (BFO) thin films were formed by depositing sol?gel solutions on Pt/Ti/SiO2/Si (1?0?0) structures. No secondary phase was observed by La-atom-substitution up to 20% in BFO thin films. The micro-structures of the films were changed with an increase in La concentration, which influenced the ferroelectric properties of the films. The dielectric constant of a BFO film was approximately 90 at 1?MHz and it increased to 125 in a 20% La-substituted BFO film, which was probably due to the size effect of grains. The substitution of La atoms in BFO films reduced the leakage current as well as remanent polarization. The leakage current contribution in the hysteresis loop was negligible when the loops were measured at above 20?kHz. The obtained saturated remanent polarization was 50??C?cm?2 in a 5% La-substituted BFO film at 100 kHz.

Small-angle neutron scattering measurements have been performed on tert-butyl alcohol–water mixtures with alcohol concentrations from 0.05 to 0.30 mole fractions at 298, 313 and 328 K. Concentration fluctuations of the mixtures are analysed in terms of fractals. The structure of the concentration fluctuation is visualized by means of a large-scale reverse Monte Carlo technique. Percolation analysis of the visualized structure shows that the concentration fluctuation is characterized by polydisperse mass fractals, as found for 1-propanol–water mixtures. It seems that polydisperse mass fractals are a common structural characteristic in various alcohol–water mixtures.

In this study, BiFeO3 (BFO) epitaxial film was deposited on SrRuO3 (100)/SrTiO3 (100) substrates using pulsed laser deposition (PLD). Phase pure BFO thin film was obtained. Introducing a mask between the target and substrate in PLD improved the surface roughness from 47.8 nm (RMS, without mask) to 7.7 nm (RMS, with mask). The composition and electrical properties of BFO thin film were assessed after annealing for 1 h in Ar, N2, or O2 atmosphere at 600°C. The P-E hysteresis properties improved only in the O2 atmosphere. After annealing under O2 atmosphere, the leakage current decreased from 6.1 × 10-2 A/cm to 2.9 × 10-2 A/cm at 200 kV/cm, as in the other annealing atmospheres, but 2Pr increased from 35 BC/cm2 to 50 BC/cm2.

An all-epitaxial stacked ferroelectric capacitor, from the conductive plug to the top electrode, fabricated on a silicon substrate with a metal-oxide-semiconductor field-effect transistor is described. An SrRuO 3 /Pb(Zr,Ti)O 3 /Ir/TiN/Si(100) heteroepitaxial structure with epitaxially grown thin films on a silicon substrate had good crystallinity. Each thin film was oriented in the (100) direction with a cube-on-cube alignment on the silicon crystal lattice. The switching charges of fabricated epitaxial capacitors were around 36 μ C/cm 2 . The charge was less dependent on size for capacitors larger than 5 × 5 μ m.

SrBi2Ta2O9 (5%)- and (Bi, La)4Ti3O12 (5%)-incorporated BiFeO3 thin films were fabricated by chemical solution deposition on Pt/Ti/SiO2/Si (100) structures. The mixed composition films showed lower leakage current density at high electric fields than pure BFO films. Because of the low leakage current density in the mixed films, polarization hysteresis loops with the remanent polarization of 80 μC/cm2 and 40 μC/cm2 were obtained at 1 kHz frequency in SBT- and BLT-incorporated films, respectively.

Extended X-ray absorption fine structure (EXAFS) and neutron diffraction measurements, and the detailed structural modeling by reverse Monte Carlo (RMC) simulation have been performed in order to study the short- and intermediate-range structures of liquid Rb–Se mixtures. The Se chains in the liquid mixture are strongly bent to form horseshoe-like Se chains with Rb atoms at the chain ends, creating a large amount of voids. The interaction between Rb and Se atoms is very weak and Rb atoms come close together. Near the boundary of the miscibility gap at low temperature the short Se chains link up to form a large cluster, and Rb atoms sit around it. The structure factor S ( Q ) in the liquid mixture has a small pre-peak at ∼1.3 A -1 . The computed partial S i j ( Q ) for the RMC model indicates that the pre-peak is associated with the Se–Se interchain component of S ( Q ). The voids in the structure play an important role in the appearance of the pre-peak in S ( Q ). From the void analysis using Delaunay tes...

Neutron diffraction measurements, and structural modelling by reverse Monte Carlo simulation, have been performed for liquid Rb–Se mixtures in the Se-rich concentration range. In the liquid mixtures some of the Se chains are strongly bent to form ring-like Se chains with Rb atoms at the chain ends, creating a large amount of voids. The shortened Se chains link up to form a large cluster, and Rb atoms sit around it near the boundary of the miscibility gap at low temperature. The structure factor S(Q) exhibits a small pre-peak at ~1.3 A−1. From the void analysis it has been revealed that the observed pre-peak corresponds to a pre-peak in the concentration–concentration structure factor due to the chemically ordered packing of the interstitial voids and Se chains in the structure.

During the reactions related to oxidative steam reforming and combustion of methane over α-alumina-supported Ni catalysts, the temperature profiles of the catalyst bed were studied using an infrared (IR) thermograph. IR thermographical images revealed an interesting result: that the temperature at the catalyst bed inlet is much higher under CH4/H2O/O2/Ar = 20/10/20/50 than under CH4/H2O/O2/Ar = 10/0/20/70; the former temperature is comparable to that over noble metal catalysts such as Pt and Pd. Based on the temperature-programmed reduction and oxidation measurements over fresh and used catalysts, the metallic Ni is recognized at the catalyst bed inlet under CH4/H2O/O2/Ar = 20/10/20/50, although it is mainly oxidized to NiAl2O4 under CH4/H2O/O2/Ar = 10/0/20/70. This result indicates that the addition of reforming gas (CH4/H2O = 10/10) to the combustion gas (CH4/O2 = 10/20) can stabilize Ni species in the metallic state even under the presence of oxygen in the gas phase. This would account for its extremely high combustion activity.

Catalyst bed temperature during the oxidative steam reforming of methane over α-Al 2 O 3 -supported Ni catalysts, prepared from three different precursors (nickel nitrate, nickel acetate and nickel chloride), was studied with infrared thermograph at 1073 K. It was found that the temperature near the catalyst bed inlet increased with decreasing W / F (contact time W / F : W (g): catalyst weight, F (mol/h): total flow rate of the introduced gases) in oxidative steam reforming of methane. It is thought that the bed temperature profile is influenced by the catalytic activities of methane combustion and reforming reactions. However, in the case of Ni/α-Al 2 O 3 , it was intriguing to find that the highest bed temperature was not so influenced by the metal loading, dispersion and preparation method. The reason for this interesting result is because the catalyst with higher combustion activity has higher reforming activity. Consequently, higher temperature, which is caused by high combustion activity, is compensated to the similar level by means of endothermic reforming.

Absolute intensity of small angle neutron scattering (SANS) has been measured for 1-propanol aqueous solution. Fractal dimension evaluated from the observed intensity depends on 1-propanol content in a peculiar way. Mesoscale structure of the solution has been visualized by means of large-scale reverse Monte Carlo (RMC) technique. It is suggested that most molecules are located on surface of clusters and cluster-size distribution obeys a simple power law.

Temperature profiles and catalytic performance over α-alumina-supported nickel catalysts with various Ni loadings (0.2−10 wt %) were studied during the oxidative steam reforming of methane. The catalyst bed temperature during the reaction was dependent on the Ni loading amount. From the viewpoint that the formation of hot spots can be inhibited to some extent, 0.9 wt % Ni was a suitable catalyst in our case, which exhibited the lowest bed temperature at W/F = 0.4 g·h/mol. To investigate the factors that control the bed temperature during the oxidative steam reforming of methane, first, the steam and CO2 reforming of methane was carried out. It was found that the methane conversion gradually increased with increasing Ni loading. Second, the catalytic behavior was examined when the reforming gas (CH4/H2O) was added to the combustion gas (CH4/O2). The results revealed that over the catalyst with lower Ni loading, the combustion activity was rather low; however, the combustion activity and the catalyst bed te...

Temperature profiles of alumina supported Rh, Pt and Pd catalysts were investigated during the reactions related to autothermal reforming of methane by means of IR thermography. From the results of the mixture of reforming gas (CH 4 :H 2 O = 1:1) with combustion gas (CH 4 :O 2 = 1:2), we evaluated the overlap between the reforming and the combustion reaction zones. The most significant overlap was observed over Rh catalyst. In addition, the effect of W / F and reaction temperature on the temperature profiles and catalytic performance in the autothermal reforming reaction were systematically examined. The overlap between these reaction zones led to a higher methane conversion even at lower W / F during autothermal reforming of methane; such an overlap was considered to contribute to the inhibition of the hot spot formation. This phenomenon demonstrated an efficient heat transfer from exothermic combustion to endothermic reforming.