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It is shown experimentally that relative movement of shrink-fit connections occurs on mating surfaces even if the transmitting torque does not exceed the static frictional torque. However, there is a transmitting torque threshold below which no relative movement occurs. The experimental thresholds agree well with predictions from theoretical calculations of the slip model, which is based on the numerical results of shear stress variation along the interface and on Coulomb's law of friction.

A thallium bromide (TlBr) gamma-ray detector was developed for particle-induced gamma-ray emission (PIGE) applications. The PIGE spectrum of a lithium fluoride (LiF) crystal was obtained for the first time using the TlBr detector. This detector was fabricated using a zone-purified crystal with dimensions of approximately 2mm × 2mm × 5mm. An energy resolution of 2.3% full-width at half maximum for 511 keV gamma rays was obtained from the detector at room temperature. The LiF crystal target was irradiated with a 20 MeV proton beam at the Aomori Prefecture Quantum Science Center. Full-energy peaks of 478 keV and 197 keV were successfully detected from lithium and fluorine, respectively, using the TlBr detector in the PIGE experiment. [ABSTRACT FROM AUTHOR]

The Chinese yam is a major component of the Japanese diet consumed in raw and cooked form. It is important to determine the nutrient contents of yam, which contains high potassium levels; a simple measurement method is required. We performed proton-induced X-ray emission (PIXE) analysis of fully grown and immature yams. Analysis of the yam trunk, skin, and hair roots revealed that the skin potassium concentration was 10-fold higher than that of the trunk; consumption of the skin is thus recommended. Longitudinal measurements of mineral concentrations in a growing yam revealed that the concentrations increased in the growth direction. [ABSTRACT FROM AUTHOR]

We subjected white birch milk to X-ray emission analysis. The mineral levels changed over time. White birch seasonality (sprouting in early spring and fruition in autumn) affected the mineral levels. [ABSTRACT FROM AUTHOR]

Here, we apply 20 MeV particle-induced X-ray emission (PIXE) to elemental analysis of microplastic samples with a diameter of approximately 2 mm, collected from the seashores of the northeastern area of Honshu in Japan. The samples were in a grain form with unwanted elements adhering to their surfaces. The PIXE measurements were conducted in a helium atmosphere. For normalization, the number of K X-rays of the residual gas argon was used instead of the directly measured beam irradiation, and the number of continuous X-rays in the PIXE spectrum was used instead of the mass of each sample. Thirteen elements were identified on the microplastics, among which were toxic chromium and lead. Thus, PIXE analysis is useful for analyzing microplastic samples. [ABSTRACT FROM AUTHOR]

Byline: M. Nogami, T. Hayakawa The sol-gel method was applied to the preparation of glasses doped with nano-sized CdS and SnO2 particles of 510nm in diameter. Band gap energies of the nano-sized particles exhibited large blue shift compared with those of bulk crystals and the energy shift was reciprocally proportional to the square of the particle size. The third order nonlinearity of the nano-sized CdS particles showed the maximum value of 1.5610-10 esu at the optical absorption edge position. The Eu+ ions were doped in the nano-sized CdS and SnO2 particles-precipitated glasses, of which the fluorescence intensities were enhanced by the existence of the nano-sized particles. The energy absorbed by the quantum-dot effect in the nano-sized particles is efficiently transferred into the Eu+ ions to cause the high emission. Particularly, the Eu+ ions doped in nano-sized SnO2-containing glasses exhibited the enhanced fluorescence of the 5D0→7Fj transitions. When excited at the energy corresponding to the absorption edge of the SnO2 nanocrystals, the fluorescence intensities of the Eu+ ions were enhanced up to 150 times higher than the glass without nanocrystals.

For the first time, particle-induced X-ray emission (PIXE) spectra were obtained using TlBr detectors. The TlBr detector was fabricated from a crystal grown with material purified by the zone purification. Its active volume was 1.5 mm × 1.5 mm × 3.1 mm, and it exhibited an energy resolution of a 6.2 keV full-width at half-maximum (FWHM) for 59.5 keV at room temperature. The detector was installed into a PIXE system at Aomori Prefecture Quantum Science Center. A Pb plate target in the PIXE chamber was irradiated with a 20 MeV proton beam, and X-ray peaks for Pb K α and K β were successfully detected by the TlBr detector at room temperature. [ABSTRACT FROM AUTHOR]

TeO2-based glasses are known to have high third-order optical nonlinear properties and promising as nonlinear optical devices. In this study, the relationship between glass structures and third-order nonlinear optical properties ReX(3) in MO-Nb2O5-TeO2 (M=Zn, Mg, Ca, Sr, Ba) glasses was investigated by femtosecond Z-scan and low-/intermediate-frequency Raman scattering. The structural correlation lengths σ of the glasses studied were estimated from a boson peak in low-frequency Raman scattering spectra. The relationship between ReX(3) and the structural correlation lengths σ was discussed. It was concluded that the longer correlation length σ brought about the higher ReX(3) in MO-Nb2O5-TeO2 glass. [ABSTRACT FROM AUTHOR]

The present study was aimed to fabricate thin films of TeO2-based glasses by a sol-gel process. It was here demonstrated that to control the hydrolysis reaction of Te-alkoxide with a chelating agent of diethanol-amine and in low-humidity environment was important because the hydrolysis reaction was extremely rapid. As a result, transparent TeO2-TiO2 thin films were successfully formed by dip-coating and subsequent heat-treatment. TiO2 component was found to be effective not only for more moderate hydrolysis reaction but also for an increase of refractive index. Photoluminescence properties of Eu3+ ions in TeO2-TiO2 thin film were also investigated. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to compare two analytical methods-maximum slope (MS) and the dualinput single-compartment model (CM)-in computed tomography (CT) measurements of hepatic perfusion and to assess the effects of extrahepatic systemic factors.Materials and Methods: A total of 109 patients underwent hepatic CT perfusion. The scans were conducted at the hepatic hilum 7-77 s after administration of contrast material. Hepatic arterial perfusion (HAP) and portal perfusion (HPP) (ml/min/100 ml) and the arterial perfusion fraction (APF, %) were calculated with the two methods, followed by correlation assessment. Partial correlation analysis was used to assess the effects on hepatic perfusion values by various factors, including age, sex, risk of cardiovascular disease, compensation for respiratory misregistration, arrival time of contrast material at the abdominal aorta, transit time from abdominal aorta to hepatic parenchyma, and liver dysfunction.Results: The mean HAPs, HPPs, and APFs were, respectively, 31.4, 104.2, and 23.9 for MS and 27.1, 141.3, and 22.1 for CM. HAP and APF showed significant (P<0.0001) and moderate correlation (γ=0.417 and 0.548) and HPP showed poor correlation (γ=0.172) between the two methods. While MS showed weak correlations (γ=-0.39 to 0.34; P<0.001 to <0.02) between multiple extrahepatic factors and perfusion values, CM showed weak correlation only between the patients' sex and HAP (γ=0.31, P=0.001).Conclusion: Hepatic perfusion values estimated by the two methods are not interchangeable. CM is less susceptible to extrahepatic systemic factors. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) for detection and subtype classification in pulmonary adenocarcinomas through comparison with short TI inversion recovery turbo spin-echo imaging sequence (STIR).Methods: Thirty-two patients (mean age, 65.2 years) with 33 adenocarcinomas (mean diameter, 27.6 mm) were enrolled in this study. The detection rates of both sequences were compared. The ADC values on DWI and the contrast ratio (CR) between cancer and muscle on STIR were measured and those were compared across subtype classifications. Finally, ROC-based positive tests were performed to differentiate subtype classifications, and differentiation capabilities were compared.Results: The DWI detection rate [85% (28/33)] was significantly lower than that of STIR [100% (33/33), P < 0.05]. The ADC values showed no significant difference regarding subtype classification; however, the CRs of bronchio-alveolar carcinomas (BACs) were significantly lower than those of other types (P < 0.05). When threshold values for differentiating BACs from others were adapted, the sensitivity and accuracy of DWI were significantly lower than those of STIR (P < 0.05). For differentiating adenocarcinomas with mixed subtypes from those with no BA component, there were no significant differences between the two sequences.Conclusion: STIR is more sensitive for detection and subtype classification than DWI. [ABSTRACT FROM AUTHOR]

Abstract: A new class of proton conducting glass membranes for hydrogen fuel cell applications are being developed using phosphotungstic acid. These glasses are being design to yield high proton conductivities could be potential substitutes for electrolytes in H2/O2 fuel cell. P2O5–SiO2–PWA glasses have been non-crystalline phases confirmed by structural studies. The glass materials showed good mechanical and thermal stability, and also found a maximum proton conductivity of 9.1×10−2 S/cm at 90°C and 30% RH. The average pore size less than 5nm was determined by Barrett–Joyner–Halenda (BJH) desorption method. The electrochemical activity was investigated by polarization curves and current–voltage profiles. A maximum power density value of 10.2mW/cm2 was obtained using 0.15mg/cm2 of Pt/C loaded on electrode and 5P2O5–87SiO2–8PWA glasses at 30°C and 30% humidity. [Copyright &y& Elsevier]