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Rationale and Objectives To compare degradation of the image quality due to beam hardening artifacts in reduced-iodine-dose virtual monochromatic imaging (VMI) between a new fast kVp switching dual-energy computed tomography (CT) scanner (Revolution CT) and the conventional dual-energy scanner (Discovery CT). Materials and Methods First, a phantom study was performed to quantitatively evaluate beam hardening artifacts in images obtained by VMI reconstruction at different energy levels. In the second study, we performed a retrospective evaluation of the images of 28 patients who had undergone reduced-iodine (300 mg/kg) dual-energy scanning in both Revolution CT and Discovery CT. We evaluated each image quantitatively by measuring the contrast-to-noise ratio (CNR) and qualitatively by scoring the artifacts and image quality. We also calculated the modulation transfer function (MTF) and noise power spectrum (NPS) of the two scanners. Results In the phantom study, VMI reconstruction of the CT images at 40–70 keV was associated with a significantly greater reduction in the severity of the artifacts in the Revolution CT images as compared to the Discovery CT images. In the retrospective study, there were no significant differences in the CT value of the aorta, noise, or CNR between the two scanners, but the scores for image quality were significantly higher in the Revolution CT images as compared to the Discovery CT images. The MTF of Revolution CT was higher than that of Discovery CT, reflecting the better spatial resolution. Conclusion In Revolution CT, beam hardening artifacts were reduced in reduced-iodine VMI at lower energy levels compared to Discovery CT, contributing to better image quality.

Nakajo-Nishimura syndrome, which is a specific autoimmune disorder characterized by chronic inflammation, emaciation, and exhaustion, is inherited in an autosomal recessive fashion and is representative of proteasome dysfunction. Its main clinical features include pernio-like red-to-purple skin plaques on the hands and feet, periodic fever, progressive localized atrophy of fat and muscle, emaciation, elongated and thickened fingers and toes, joint contractures, enlarged liver, basal ganglia calcification, and a heliotrope rash. The dental treatment for three patients with Nakajo-Nishimura syndrome is described. Dental extractions and procedures were successfully performed without causing any obvious intraoperative or postoperative complications, although all three patients showed progressive trismus. When performing a dental procedure in patients with proteasome dysfunction, preoperative antibiotic therapy should be given because they are susceptible to infection due to the long-term use of high-dose steroids. Drug-related osteonecrosis of the jaw should also be considered. Proteasome dysfunction is characterized by joint contractures and progressive fat and muscle atrophy; thus, the patients are also likely to have reduced mouth opening, and it is a challenge for them to clean their teeth by brushing, which may lead to the occurrence of dental caries in molars. Therefore, scheduling regular interventions by dentists needs to be considered for patients with proteasome dysfunction.

Herein, a method has been described to rapidly obtain a semi-quantitative three-dimensional lithium distribution of a lithium-ion battery graphite anode using laser-induced breakdown spectroscopy (LIBS) measurements. LIBS measurements of the graphite anodes with a diameter of 10 mm were performed in an argon atmosphere of 1000 Pa until the depth of 150 μm using the Li emission line of 610.4 nm. The emission intensity was measured for the pitch of 500 μm in plane. Homogeneous and inhomogeneous lithium distributions were observed in the anodes after both charge and charge-discharge processes. The inhomogeneous lithium distribution after the charge process was attributed to the preferentially reacted area in the anode, while that after the charge-discharge process was likely related to the low desolvation reaction rate of lithium ions at the solid electrolyte interphase. These inhomogeneous lithium distributions were consistent with the results from the charge-discharge curves and the lithium ion transfer mechanism. Thus, it was proven that it is possible to acquire a three-dimensional lithium distribution of a graphite anode of a lithium-ion battery by LIBS measurements.

Metropolitan Tokyo is located directly above a subduction zone that has generated two megathrust earthquakes in the past 300 years. However, the timing of older megathrusts on this margin is poorly understood. In this study, we aim to constrain the timings of past megathrust earthquakes, using coastal stratigraphy, paleoecology, radiocarbon dating and archaeological records from coastal lowlands. An investigation of 13 boreholes in the southern coastal area of metropolitan Tokyo found evidence for 4 m of uplift in a 6000-year period. However, we found that net vertical displacement in the last 1000 years is approximately zero. Results suggest that preservation of usually ephemeral lagoon sediments occurred on three occasions in the past 1000 years, and radiocarbon dating results show that the timings of these preservation episodes are close to that of major historical earthquakes. We thus attribute the intermittent preservation of the ephemeral lagoon deposits to coseismic uplift caused by the megathrust earthquakes. The candidates of the megathrust earthquakes are events that took place in 1703 CE, the 13th century, and 878 CE. Since these events produced no net vertical displacement due to inter-seismic subsidence, we propose that earthquakes responsible for long-term uplift of this region took place prior to the 9th century. This research also demonstrates the value of preserved intertidal sediments as paleoseismological archives where net tectonic displacement is neutral.

Cross-sectional shape-controlled Fe-Ga alloy crystals for energy harvester applications were grown using the micro pulling down (μ-PD) method. The investigation of material concentrations along the growth direction reveals that a high growth rate of 5.0 mm/min raises the effective segregation coefficient of Ga, k eff (Ga), and ensures high concentration homogeneity. However, the high growth rate was speculated as causing non-preferentially oriented portion formation that decreases the magnetostrictive property. The magnetostriction 3/2λ = 286 ppm was achieved for a good oriented sample (i.e. the misorientations from 〈100〉 were less than 7.5°.) with the Ga concentration of 16.8 at%. A prototype vibration energy harvester using a plate-shaped Fe-Ga alloy grown at 5.0 mm/min showed comparable or superior performance to the device using commercially available alloys. By leveraging the advantages of near net-shape controlling and a higher growth rate than other crystal growth techniques, the μ-PD method is expected to emerge as a new technique for mass-producing Fe-Ga alloys as materials for energy harvester applications.

In order to apply magnetostrictive materials in vibration energy harvesting devices, large-sized ingots of Fe–Ga alloy single crystals exhibiting large magnetostriction were successfully grown using the Czochralski method. The performance of power generation using the 〈1 0 0〉-oriented crystal has been evaluated using simply designed devices. Specifically, influences of magnetic fields produced by inverse magnetostriction of the crystal and permanent magnets on power generation have been studied. The results indicated that power generation using the Fe-Ga alloy single crystal result from the inverse magnetostriction and the magnetic fluxes generated by electromagnetic inductions, which are caused by the cyclic relative motion between a coil and permanent magnets using the simple device frame structures. It was shown that the alloy single crystal acts as a magnetic core, and that the alternating current produced via vibration energy harvesting can be converted to direct current for charging batteries.

In this study, in situ white X-ray microbeam diffraction experiments were conducted to investigate the microscopic deformation behavior of a Cu-Al-Mn superelastic alloy during tensile testing. Local deformation both at a grain scale and an intragranular scale was revealed by analyzing Laue spot streaking that occurred within a grain and in some grains with different orientations. The streaking measured within a grain under tensile load showed inhomogeneous behavior because of an inhomogeneous martensitic transformation. Moreover, the effect was dependent on grain orientation. In a grain with a high Schmid factor, a large dispersion in the 2θ diffraction angle of Laue spots was observed due to significant Laue spot streaking, which can be attributed to that grain's favored martensitic transformation.

This paper qualitatively explains the differences in the cathodoluminescence (CL) colors of alumina (Al 2 O 3 ) inclusions in steels and presents a method of distinguishing MgAl 2 O 4 spinel inclusions from other inclusions using CL imaging. It was found that the presence of chromium (Cr) and titanium (Ti) in Al 2 O 3 inclusions increases CL intensity in the red region, while elements that increase oxygen vacancies such as magnesium relatively increase CL intensity in the blue region. We could distinguish MgAl 2 O 4 spinel inclusions, which produce green luminescence, from Al 2 O 3 inclusions by capturing CL images. We were also able to identify MgAl 2 O 4 spinel in an agglomerated inclusion consisting of MgAl 2 O 4 spinel, Al 2 O 3, and MgO from its CL image. Capturing CL images whose wavelength is less than 600 nm simplifies the identification of Al 2 O 3 and MgAl 2 O 4 spinel inclusions because all the Al 2 O 3 and MgAl 2 O 4 spinel inclusions produced blue and green luminescence, respectively. The present study suggests that CL image capture is a rapid identification method for inclusions in steels, especially MgAl 2 O 4 spinel and Al 2 O 3 inclusions, because it takes less than 30 s to obtain CL images.

Glucocorticoids are important therapeutic compounds for acute lymphoblastic leukemia (ALL). AKT1 or the protein kinase B is frequently activated in ALL, and contributes to the development of glucocorticoid resistance. We examined impact of AKT1 on glucocorticoid receptor (GR)-induced transcriptional activity in cooperation with phospho-serine/threonine-binding protein 14-3-3. AKT1 has two distinct actions on GR transcriptional activity, one through segregation of GR in the cytoplasm by phosphorylating GR at Ser-134 and subsequent association of 14-3-3, and the other through direct modulation of GR transcriptional activity in the nucleus. For the latter, AKT1 and 14-3-3 are attracted to DNA-bound GR, accompanied by AKT1-dependent p300 phosphorylation, H3S10 phosphorylation and H3K14 acetylation at the DNA site. These two actions of AKT1 regulate distinct sets of glucocorticoid-responsive genes. Our results suggest that specific inhibition of the AKT1/14-3-3 activity on the cytoplasmic retention of GR may be a promising target for treating glucocorticoid resistance observed in ALL.

Although ameloblastoma is generally considered to be a benign tumor, local recurrences have often been noted. On the other hand, however, lung metastasis is quite rare. Here, we present a case of a patient who had ameloblastoma in the mandible with metastases in a lung and several recurrences. The patient was a 24-year-old man who was treated, but developed lung metastasis 1 year later. Once it had metastasized, recurrences occurred twice. Histologically, both the primary tumor and lung metastasizing tumor were benign. The patient died 27 years after the initial treatment and 14 years after detection of pulmonary metastasis. To our knowledge, this patient was the longest-survival case in Asia for such conditions.

The local stress state developed during the elastic deformation of polycrystalline Fe-17mol%Ga was measured by synchrotron white X-ray radiation, and the heterogeneity of the elastic deformation resulting from the pronounced elastic anisotropy of the Fe–Ga alloy system was examined. Tensile loading generated local stresses perpendicular to the tensile direction. The development of these stresses was discussed from the viewpoint of the interaction between grains having different elastic properties.

Eu doped LiSrAlF6 (Eu:LiSAF) crystals with various Eu concentrations were grown by a micro-pulling-down (μ-PD) method and the effects of Eu concentration control on crystal growth and scintillation properties for Eu:LiSAF crystals were investigated as a neutron scintillator. As-grown Eu0.3%:LiSAF crystal had no visible inclusion while milky parts were observed in the crystals with higher Eu contents. The secondary phases with the chemical composition of EuF2 or EuF3 in the Eu:LiSAF matrix were observed for the crystals with high Eu contents while the secondary phase couldn’t be observed in the powder XRD patterns. In the radioluminescence spectra of Eu:LiSAF crystals under α-ray irradiation, emission peaks around 375 nm originated from 5d–4f transition of Eu2+ ion were observed. The light yields systematically increased with an increase of actual Eu contents in the crystals and the decay times were 1490–1620 ns.

Fine crystalline LiFePO 4 particles with an average secondary size of about 200 nm were synthesized in ethylene glycol (EG) solution at 393 K. Their molar ratio of Li:Fe:P was about 1.3:1:1, implying the precipitation of an impurity containing extra Li ions. The unit cell volume of crystalline LiFePO 4 in heat-treated particles was larger than that in as-synthesized particles. The Fe K absorption edge in the X-ray absorption spectrum was shifted toward a lower energy position by heat treatment. These results suggest that the composition of crystalline LiFePO 4 in fine particles is modified by heat treatment because of the reaction with extra Li ions. Additionally, in the radial structural function obtained by Fourier transform of the extended X-ray absorption fine structure oscillation, the Fe–P correlation and Fe–Fe correlation peaks became high due to the heat treatment, implying the rearrangement of FeO 6 octahedra and PO 4 tetrahedra. In consequence of the above-mentioned structural changes, the electronic capacity of fine particles precipitated in EG solution was enhanced to about 150 mA/h by heat treatment at 673 K.

The itinerant-electron metamagnetic transition of La(Fe0.88Si0.12)13 becomes indistinct after immersion in distilled-water containing about 8 ppm of the dissolved oxygen (DO) concentration because of aqueous corrosion. However, the aqueous corrosion of La(Fe0.88Si0.12)13 is significantly suppressed by reducing the DO concentration. Thus, isothermal magnetic entropy change after immersion for 30 days in deaerated distilled-water with a DO concentration less than 0.1 ppm is larger than that after immersion for 5 days in distilled-water containing about 8 ppm of the DO concentration. Consequently, the reduction of the DO concentration is effective for preservation of the excellent magnetocaloric effects of La(Fe0.88Si0.12)13 in an aqueous solution, which is a promising heat transfer fluid of room-temperature magnetic refrigeration.

The functionality of a newly developed silicone oil-free (SOF) syringe system, of which the plunger stopper is coated by a novel coating technology (i-coating™), was assessed. By scanning electron microscopy observations and other analysis, it was confirmed that the plunger stopper surface was uniformly covered with the designed chemical composition. A microflow imaging analysis showed that the SOF system drastically reduced both silicone oil (SO) doplets and oil-induced aggregations in a model protein formulation, whereas a large number of subvisible particles and protein aggregations were formed when a SO system was used. Satisfactory container closure integrity (CCI) was confirmed by means of dye and microorganism penetration studies. Furthermore, no significant difference between the break loose and gliding forces was observed in the former, and stability studies revealed that the SOF system could perfectly show the aging independence in break loose force observed in the SO system. The results suggest that the introduced novel SOF system has a great potential and represents an alternative that can achieve very low subvisible particles, secure CCI, and the absence of a break loose force. In particular, no risk of SO-induced aggregation can bring additional value in the highly sensitive biotech drug market. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1520–1528, 2014

Influence of tungstate ions on the transformation of chloride-containing green rust (GR(Cl − )) to fine goethite (α-FeOOH) particles due to the oxidation reaction via aqueous solution at about 300 K was investigated by in situ measurements of X-ray absorption spectra. Results showed that the transformation rate of GR(Cl − ) in the suspension containing 5 mol% W was lower than that in the suspension without tungstate ions. Almost all tungstate ions in the suspension were adsorbed on GR(Cl − ) and α-FeOOH. It is probable that the adsorption of tungstate ions reduces the transformation rate of GR(Cl − ) and also leads to the precipitation of fine particles.

We analyzed the dislocation distribution of cold-drawn pearlitic-steel wire by using the line-profile analysis based on the energy dispersive X-ray diffraction (EDXD). Although this line-profile analysis requires a high resolution in reciprocal space, the resolution for EDXD is generally poor due to the energy resolution of the detector. Our analysis demonstrated that the resolution in the reciprocal space can be maximized at small scattering angles. Using the line-profile analysis based on the EDXD, the microstructural parameters such as the crystallite size and the dislocation density of the ferrite phase in the pearlitic steel were successfully analyzed. In addition, the distribution of the residual stress of the ferrite phase of a pearlitic steel wire was also analyzed using the EDXD measurement.

By annealing at 1323 K, the single-phase formation process of La(Fe0.89Si0.11)13 with a cubic NaZn13-type structure was investigated. A dendritic microstructure composed of an α-Fe phase with a mean size of about 10 μm and a LaFeSi phase in the as-solidified state is completely changed into the NaZn13-type single-phase by annealing for 300 h. The growth of the NaZn13-type phase is steep up to an annealing time ta = 100 h, and then becomes sluggish. As a result, the maximum isothermal magnetic entropy change, Δ S m max , markedly increases with increasing ta up to 100 h in response to the formation of the NaZn13-type phase. In addition, the position of Δ S m max shifts to higher temperature ranges due to the increase of the Curie temperature TC. Accordingly, thorough annealing for the single-phase formation of La(FexSi1−x)13 is important for high-performance magnetic refrigerants.

In this work, the ZnO spherical nanoparticles with a diameter in the range of 10–30 nm have been prepared via mechanochemical oxidation of metallic Zn powders treated in a vibratory ball mill in the presence of air and liquid nitrogen. The as-prepared nanocrystals were characterized by XRD, HR-TEM, FTIR, XPS, and UV–vis spectroscopy. The results show that metallic zinc powder is completely converted to nanocrystalline ZnO within 48 h of cryomilling. The XPS analysis confirms the presence of incorporated nitrogen as well as Zn(OH)2 and carbonate species formed on the reactive structurally-disordered surface shell of the as-prepared nanoparticles. Compared with the pure ZnO, the light absorption by the as-prepared ZnO nanocrystals was shifted to longer wavelengths.

Objectives To compare the performance of model-based iterative reconstruction (MBIR) with that of standard filtered back projection (FBP) for measuring vascular wall attenuation. Study design After subjecting 9 vascular models (actual attenuation value of wall, 89 HU) with wall thickness of 0.5, 1.0, or 1.5 mm that we filled with contrast material of 275, 396, or 542 HU to scanning using 64-detector computed tomography (CT), we reconstructed images using MBIR and FBP (Bone, Detail kernels) and measured wall attenuation at the center of the wall for each model. We performed attenuation measurements for each model and additional supportive measurements by a differentiation curve. We analyzed statistics using analyzes of variance with repeated measures. Results Using the Bone kernel, standard deviation of the measurement exceeded 30 HU in most conditions. In measurements at the wall center, the attenuation values obtained using MBIR were comparable to or significantly closer to the actual wall attenuation than those acquired using Detail kernel. Using differentiation curves, we could measure attenuation for models with walls of 1.0- or 1.5-mm thickness using MBIR but only those of 1.5-mm thickness using Detail kernel. We detected no significant differences among the attenuation values of the vascular walls of either thickness (MBIR, P = 0.1606) or among the 3 densities of intravascular contrast material (MBIR, P = 0.8185; Detail kernel, P = 0.0802). Conclusions Compared with FBP, MBIR reduces both reconstruction blur and image noise simultaneously, facilitates recognition of vascular wall boundaries, and can improve accuracy in measuring wall attenuation.

To evaluate the MR findings of ruptured endometrial cyst, focusing on the differentiation from tubo-ovarian abscess (TOA).We reviewed the records of 21 patients who underwent preoperative MR examinations for TOAs (n=15) or ruptured endometrial cysts (n=6). We evaluated the presence of hyper-intense ascites and hyper-intense peritoneum in T1-weighted sequences, strong enhancement of the peritoneum, hyper-intense content and hyper-intense rim of the ovarian lesion in T1-weighted sequences, and strong wall enhancement of the ovarian lesion. χ2 test was used to assess the relationship between TOA cases versus cases with ruptured endometrial cysts, and the three MR peritoneal findings. We evaluated the relationship between TOA versus non-infected endometrial cysts, and the ovarian MR peritoneal findings, too.Hyper-intense ascites was found in all of the patients with ruptured endometrial cyst and none with TOA (p0.0001). Hyper-intense peritoneum was observed in only TOAs cases (4 of 8). Strong peritoneal enhancement was seen in 3 of the 3 patients with ruptured endometrial cyst and 7 of the 13 patients with TOA (p=0.1366). Hyper-intense content of the ovarian lesion was seen more often in the non-infected endometrial cysts than in the TOAs (p=0.001607), while hyper-intense rim was more frequent in TOAs (p=0.000402). Strong wall enhancement was observed only in TOAs (11 of 15) (p=0.001355).MR images are useful to differentiate ruptured endometrial cyst from TOA.

Objective Using an anthropomorphic phantom, we have investigated the feasibility of digital tomosynthesis (DT) of flat-panel detector (FPD) radiography to reduce radiation dose for sinonasal examination compared to multi-detector computed tomography (MDCT). Materials and methods A female Rando phantom was scanned covering frontal to maxillary sinus using the clinically routine protocol by both 64-detector CT (120 kV, 200 mA s, and 1.375-pitch) and DT radiography (80 kV, 1.0 mA s per projection, 60 projections, 40° sweep, and posterior–anterior projections). Glass dosimeters were used to measure the radiation dose to internal organs including the thyroid gland, brain, submandibular gland, and the surface dose at various sites including the eyes during those scans. We compared the radiation dose to those anatomies between both modalities. Results In DT radiography, the doses of the thyroid gland, brain, submandibular gland, skin, and eyes were 230 ± 90 μGy, 1770 ± 560 μGy, 1400 ± 80 μGy, 1160 ± 2100 μGy, and 112 ± 6 μGy, respectively. These doses were reduced to approximately 1/5, 1/8, 1/12, 1/17, and 1/290 of the respective MDCT dose. Conclusion For sinonasal examinations, DT radiography enables dramatic reduction in radiation exposure and dose to the head and neck region, particularly to the lens of the eye.

Changes in the crystal structure of type 430 stainless steel and the oxides on its surface were studied in situ at 1373 K using a high-intensity synchrotron X-ray source provided by SPring-8 in Japan. The surface of the steel was initially covered with Cr2O3, which was then converted to FeCr2O4, and finally Fe3O4 and Fe2O3 formed on it. These results indicated that the reason for the breakaway oxidation in type 430 stainless steel is Cr depletion beneath Cr2O3 layer and the subsequent ionisation of Fe, not the simple mechanical failure of Cr2O3.

The leaching characteristics of scorodite particles synthesized from Fe(II) under different conditions, such as reaction time and temperature, were investigated. The solution conditions, such as pH and temperature, were changed in leaching experiments. The results showed that the leaching characteristics depend on the synthesis temperature of scorodite particles, particle size, type of solvent and so on. Since the amount of As dissolved from particles with the high Fe/As molar ratio is relatively low, the Fe/As molar ratio of the particles is an important factor to control the dissolution of As from scorodite particles. The results of leaching tests with repeated renewal solution showed that pH of solution is the most important factor in the As dissolution. It was found that the addition of goethite to the scorodite is also effective to reduce the amount of As in solution.

To evaluate the skin dose during cerebral CT perfusion on a phantom, and estimate the weighted CT dose index (CTDIw) to maximum skin dose conversion factors for four types of CT scanners.We evaluated the relationship between surface dose during cerebral CT perfusion and distance from the scan center in the x-y plane using a 64-multidetector row CT scanner. Skin doses were also assessed with 4 different 64-multidetector CT scanners.The surface doses decreased with the distance from the scan center in the x-y plane. The surface doses at the points 6 cm and 10 cm from the scan center in the x-y plane were different from the dose at the point 8 cm by about 15%. CTDIw and skin doses differed among the CT scanners (CTDIw, 143-590 mGy; averaged temporal skin dose, 126-590 mGy). For all the four types of CT scanner, the doses increased in the following order: occipital pointfrontal pointtemporal points. The ratios of the maximum skin dose (averaged temporal skin dose) to CTDIw differed among the CT scanners (64-100%).The maximum skin dose during cerebral CT perfusion and the dose to CTDIw ratios differs among CT scanners. The CTDIw is useful for estimation of the maximum skin dose during cerebral CT perfusion using a proper conversion factor specific to each type of CT scanner.

The formation processes of trace fossils – including shallow to deep pits, notches, borings (tunnels), and channels, particularly at the limb joints – observed on the surfaces of Velociraptor , Protoceratops , ankylosaurid, and Bagaceratops skeletons from Upper Cretaceous eolian deposits in the Gobi desert, Mongolia were investigated. The median diameters of these structures ranged from 5.25 to 7.68 mm. These structures were likely created by insects scavenging on dinosaur carcasses. This interpretation is corroborated by the presence of burrows of a size similar to the trace fossils observed on the dinosaur bone surfaces at the same locality. Broad borings (about 32 mm in diameter) created by small Mesozoic mammals have also been discovered on the ribs and scapulae of a Protoceratops skeleton. Dinosaur skeletons found at two localities, Tugrikin Shireh and Khermeen Tsav, and two formations, the Djadokhta Formation and Barun Goyot Formation, exhibited the same type of damage to the limb joints. The high frequency of trace fossils at the limb joints suggests that small animals targeted the collagen in the joint cartilage of dried dinosaur carcasses as a source of nitrogen, which was relatively scarce in the eolian environments of the Gobi desert during the Late Cretaceous.

Microstructures of tensile-deformed high-manganese austenitic steels exhibiting twinning-induced plasticity were analyzed by electron backscatter diffraction pattern observation and X-ray diffraction measurement to examine the influence of differences in their stacking fault energies on twinning activity during deformation. The steel specimen with the low stacking fault energy of 15 mJ/m{sup 2} had a microstructure with a high population of mechanical twins than the steel specimen with the high stacking fault energy (25 mJ/m{sup 2}). The and fibers developed along the tensile axis, and mechanical twinning occurred preferentially in the fiber. The Schmid factors for slip and twinning deformations can explain the origin of higher twinning activity in the fiber. However, the high stacking fault energy suppresses the twinning activity even in the fiber. A line profile analysis based on the X-ray diffraction data revealed the relationship between the characteristics of the deformed microstructures and the stacking fault energies of the steel specimens. Although the variation in dislocation density with the tensile deformation is not affected by the stacking fault energies, the effect of the stacking fault energies on the crystallite size refinement becomes significant with a decrease in the stacking fault energies. Moreover, the stacking faultmore » probability, which was estimated from a peak-shift analysis of the 111 and 200 diffractions, was high for the specimen with low stacking fault energy. Regardless of the difference in the stacking fault energies of the steel specimens, the refined crystallite size has a certain correlation with the stacking fault probability, indicating that whether the deformation-induced crystallite-size refinement occurs depends directly on the stacking fault probability rather than on the stacking fault energies in the present steel specimens. - Highlights: {yields} We studied effects of stacking fault energies on deformed microstructures of steels. {yields} Correlations between texture and occurrence of mechanical twinning are discussed. {yields} Evolutions of dislocations and crystallite are analyzed by line profile analysis.« less

To clarify the role of phosphate in the formation of corrosion products, the transformation of GRI(Cl−) with the addition of phosphate was characterized through XRD, TEM, and solution analysis. Electrochemical analysis showed that the transformation of GRI(Cl−) was delayed and the size of the final products, i.e., γ-FeOOH was reduced in the phosphate added case. X-ray absorption spectroscopy indicated that the neighboring Fe–Fe coordination number of FeO6 octahedral unit in γ-FeOOH was decreased. These effects of phosphate are attributed to its adsorption on GRI(Cl−) and nucleated γ-FeOOH that prevented particle growth during oxidation process.

The microstructure of transformation induced plasticity (TRIP) steels was characterized by means of electron backscattering diffraction (EBSD) technique to identify and quantify their different microstructures such as ferrite, bainite, and retained austenite. Further, the strain distribution in ferrite and retained austenite was analyzed during deformation. The TRIP steels were annealed by austempering for different durations to investigate the effect of the austempering time on the volume fraction change of the microstructural constituents. The quantitative analysis by EBSD coupled with an image contrast analysis revealed that the amount of retained austenite decreased and the amount of bainite increased with increasing austempering time. The mechanical properties of the TRIP steels were also affected by the austempering time. The maximum elongation was obtained in the sample austempered for 5 min, probably because of the good stability of retained austenite. The strain distribution in bcc and fcc phases during tensile deformation was characterized by evaluating the changes in the average local misorientation of the phases.

Evolutionsof martensitic transformation and textureduring cold rolling innovel bcc Fe-Mn-Al-Ni-Cr alloyswere studied.X-ray diffraction (XRD)and electron backscattering diffraction (EBSD)analysesrevealed that this alloy undergoes α→ɛ→γ’ martensitic transformation during deformation. At a20% cold rolling strain, most of the α phase transformed into γ’, and the transformed γ’ phase had aKurdjumov-Sachs (K-S)relationship with the parent α phase.Strong { hkl } and weak {110} transformation textures were formedafter deformation. This texture evolutionappeared to be related tothe variant selectionthat occurredduringthe martensitic transformation.

Air-core photonic bandgap fibers offer many unique properties and are critical to many emerging applications. A notable property is the high nonlinear threshold which provides a foundation for applications at high peak powers. The strong interaction of light and air is also essential for a number of emerging applications, especially those based on nonlinear interactions and spectroscopy. For many of those applications, much wider transmission bandwidths are desired to accommodate a wider tuning range or the large number of optical wavelengths involved. Presently, air-core photonic bandgap fibers have a cladding of hexagonal lattice. The densely packed geometry of hexagonal stacking does not allow large nodes in the cladding, which would provide a further increase of photonic bandgaps. On the other hand, a photonic cladding with a square lattice can potentially provide much larger nodes and consequently wider bandgap. In this work, the potentials of much wider bandgap with square lattice cladding is theoretically studied and experimentally demonstrated.

In this study, evolution characteristics of the texture and microstructure of Fe–Mn–Si–Cr shape memory alloys (SMAs) upon tensile deformation were investigated. Electron backscatter diffraction analysis revealed that the tensile deformation in the rolling direction (RD) of sample sheets resulted in the evolution of microstructure containing stress-induced ɛ martensite and texture components belonging to 〈1 1 1〉 and 〈1 0 0〉//RD fibers. Quantitative measurement of ɛ martensite formation in individual austenite grains at the strain levels of 4% and 5% revealed that among the 〈1 0 0〉, 〈1 0 1〉, and 〈1 1 1〉 grains which are oriented along the tensile direction, 〈1 0 1〉 oriented grain showed the highest ɛ martensite formation rate. In the recrystallized state, the volume fraction of 〈1 0 1〉 texture component in 20% tensile deformed samples was slightly higher in the transverse direction (TD) than in the RD. Because of that preferred orientation recovery strain was slightly higher in the TD sample than in the RD sample.

The oxidation of hydrosulphate green rust (GR2(SO42−)) suspension containing different chromium ion species was investigated by X-ray diffraction, X-ray absorption spectroscopy and transmission electron microscopy. The pH, oxidation–reduction potential and amount of dissolved oxygen in aqueous solutions were measured during the reactions. The results show that the addition of Cr(III)2(SO4)3 solution suppresses the transformation of GR2(SO42−) into iron oxyhydroxides and oxides in aqueous solution, while the addition of Na2Cr(VI)O4 solution promotes the transformation of GR2(SO42−) in which Cr(VI) is reduced to Cr(III); α-FeOOH particles were refined by the addition of the chromium ions.

Avian fossils from the Upper Cretaceous of Mongolia provide significant scientific insight into the evolution of early birds, primarily due to the scarcity of continental interiors with a well-documented avifauna in the Cretaceous record. This paper describes in detail the anatomy and histology of a new taxon of early ornithuromorph bird, Hollanda luceria , from the Barun Goyot Formation at Khermeen Tsav in the Gobi Desert of Mongolia. The new taxon is represented exclusively by hindlimb elements, and is characterized by having elongated hindlimbs with an extremely reduced metatarsal IV and an unusual tibiotarsal-femoral articulation centered on a highly peaked lateral articular facet of the tibiotarsus. Cladistic and ecospace analyses were also carried out in order to infer evolutionary relationships and ecology of this primitive bird. These analyses indicate that the new taxon is a previously undescribed lineage of basal ornithuromorph and an outgroup of Ornithurae ( sensu Chiappe, 2002), which may have had a cursorial lifestyle similar to that of the modern roadrunner, Geococcyx californianus .

In order to understand the aging characteristics of Cu–Ti alloys, extended X-ray absorption fine structure (EXAFS) and small-angle X-ray scattering (SAXS) measurements were performed for characterizing changes in the local structure around titanium and the precipitate size in the Cu–Ti alloys by aging at approximately 720 K after solution treatment. Cu–1.3, 2.6, and 4.5 at.% Ti alloys were prepared using high-purity base metals. The amount of titanium dissolved in the copper matrix during aging was estimated from the electrical resistivity of the alloys. The aging characteristics showed that the precipitation rate of Cu–Ti intermetallic compounds in the copper matrix increased with increasing bulk titanium amount. The local structures of titanium in precipitates, presumably Cu 4 Ti, are indistinguishable in the present alloys by EXAFS analysis because of the similarity of EXAFS functions for a Cu 4 Ti intermetallic compound and a substitutional solid solution in copper. However, the EXAFS analysis revealed that the atomic distance of a Cu–Ti pair was significantly smaller than that estimated from the atomic radii of copper and titanium, implying that there is a strong atomic correlation in the pair. SAXS measurements were carried out for analyzing the growth behavior of precipitates in alloys during aging. The SAXS results revealed that a small amount of precipitates was formed in Cu–1.3 at.% Ti in the initial aging stage, whereas precipitates with approximately 2 nm radius were formed in Cu–2.6 and 4.5 at.% Ti alloys. By aging up to 2000 s, the precipitates in Cu–1.3, 2.6 and 4.5 at.% Ti alloys grew to approximately 3.5 nm in radius. These aging characteristics were discussed on the basis of the number density of precipitates calculated from the size of precipitates and the amount of super-saturated titanium in the copper matrix.

Secondary ion mass spectrometry (SIMS) was used for characterizing the depth distribution of small amounts of alloying elements in three different copper-based dilute alloys, i.e ., copper–chromium, copper–iron, and copper–nickel–silicon alloys. The samples were annealed at high temperatures under a low oxygen partial pressure. The SIMS depth profiles revealed that oxygen penetrated the copper-based alloys, and chromium and silicon were enriched on the surface side so as to form oxides during annealing. On the other hand, chromium and silicon were depleted beneath the enriched surface layer. However, the depth profile of iron was similar to that of copper. These phenomena were likely to be correlated with the reactivity of the alloying elements with oxygen. The formation kinetics of the depleted zones of chromium and silicon has been discussed on the basis of the selective oxidation of these alloying elements.

The X-ray absorption near edge structure (XANES), the extended X-ray absorption fine structure (EXAFS) and X-ray diffraction (XRD) measurements were used for characterising the effect of the addition of copper sulphate ions on the chemical state and local structure of hydrosulphate green rust (GR). Fe K edge XANES spectra showed that Fe(II) in GR was partially oxidised by the addition of the copper sulphate solution. Cu K edge XANES spectra showed that the copper sulphate ions in the GR suspension were reduced to zero charge copper. Radial structural functions indicated that the structure of GR comprised edge sharing of FeO 6 octahedral units, which was changed by the oxidation of Fe(II). In addition, it was found that the GR was partially oxidised to α-FeOOH by the addition of copper ions.

The intrinsic zero-energy loss profiles of transition metal 2p and 3p XPS spectra for Cr, Mn, and Fe oxides are obtained by spectral deconvolution and compared with Shirley-type background corrected profiles. The metal core level spectra are deconvoluted by O 1s spectra as the response function of each oxide. As the O 1s spectra include intrinsic and extrinsic energy loss parts, the background corrected core level spectra are zero-energy loss spectra. The good agreement of the deconvoluted spectra with the reported spectra obtained by the many body effect theory indicates that the background subtraction method is accurate. A comparison of the deconvoluted with the background corrected spectra of the Shirely-type subtraction reveals that almost all the spectra coincide with each other except for Fe 3p with α-Fe 2 O 3 . The good coincidence of the Shirley-type corrected spectra with the deconvoluted and calculated spectra indicates that Shirley-type background correction can be used for daily quantitative surface analysis.

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are bioaccumulative chemicals that are considered to be toxic contaminants based on several epidemiological studies. To elucidate exposure levels of these chemicals in the present study, concentrations of PCDD/DFs, dioxin-like PCBs (DL-PCBs) and PCBs in breast milk, maternal blood and cord blood obtained from the same participants registered in a birth cohort study in Tohoku, Japan, were measured. Congener-specific analysis revealed several differences in minor congeners of these compounds among the three specimen types, although major congeners were detected in the specimens. The toxicity equivalence quantity concentrations (1998 WHO-TEF) and PCBs in breast milk, maternal blood and cord blood on the whole and on a lipid basis were in the order of breast milk > maternal blood > cord blood. Pearson's correlation coefficients of TEQs and total PCBs among the three specimens were high, with the correlation coefficient of TEQ between breast milk and maternal blood being the highest (r = 0.94, p

Structural analysis techniques such as X-ray diffraction and anomalous X-ray scattering were used for characterizing the influence of manganese on iron oxyhydroxides and oxides formed from green rust (GR) in an aqueous solution. The results showed that the formation of Fe 3 O 4 was enhanced by the addition of manganese ions during the conversion of GR2 ( SO 4 2 - ) to α-FeOOH and Fe 3 O 4 . The results obtained from anomalous X-ray scattering showed that manganese was present both in α-FeOOH and Fe 3 O 4 particles. The incorporation of manganese in α-FeOOH appears to induce the distortion of the atomic-scale structure of α-FeOOH particles formed in an aqueous solution.

A simple breath test was developed for assessment of exocrine pancreatic function employing 13C-dipeptide [ie, benzoyl-L-tyrosyl-[1-(13)C]alanine (Bz-Tyr-Ala)], and this test was examined to determine whether it can be used to diagnose exocrine pancreatic insufficiency in patients with chronic pancreatitis. The subjects, 24 patients with chronic pancreatitis and 16 healthy adult controls, underwent the Bz-Tyr-Ala breath test, in which breath samples were collected every 10 min up to 90 min after oral administration of an aqueous solution of 5-mg/kg Bz-Tyr-Ala (7 mM). They also underwent a breath test with [1-(13)C]alanine equimolar to that contained in Bz-Tyr-Ala and the N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) test. Delta13CO2 values at 10-60 min for the Bz-Tyr-Ala breath test were significantly lower in chronic pancreatitis patients than in normal controls. However, the [1-(13)C]alanine breath test results did not differ between patients and normal controls. The correlation coefficient between the Bz-Tyr-Ala breath test Delta13CO2 value at 20 min, and the results of the BT-PABA test were r=0.726 (r2=0.527, P0.0001). The results suggest that this newly developed Bz-Tyr-Ala breath test can quickly and noninvasively diagnose the exocrine pancreatic dysfunction.

Ex-situ X-ray diffraction measurements of a small amount of samples extracted from wet corrosion products freshly formed on a pure iron and iron–2 mass% silicon surfaces have been conducted using synchrotron radiation for clarifying the formation process of corrosion products. The results showed that γ-FeOOH was formed on the outer side of wet corrosion products formed on the surface of the pure iron by sodium chloride solution, while γ-FeOOH, α-FeOOH, Fe 3 O 4 , and green rusts were formed on the inner side. On the other hand, in comparison to the case of the pure iron, a significant formation of β-FeOOH was observed in the iron–silicon alloy. Influences of silicon alloying on corrosion products formed by aqueous solution containing sulfate ions were also observed. Furthermore, in-situ diffraction measurements by a conventional X-ray source were conducted for analyzing corrosion products formed on the pure iron and iron–silicon alloy surfaces by cyclic exposure to wet and dry atmospheres. The results obtained by the in-situ diffraction and ex-situ diffraction measurements on the corrosion products were consistent.

The extended X-ray absorption fine structure (EXAFS) method was used for investigating the local structures of lepidocrocite and goethite with and without silicon. The structure and morphology of these particles were investigated using X-ray diffraction and transmission electron microscopy, respectively. The bonding structure was examined by Fourier transform infrared spectroscopy (FT-IR). When silicon species was added, the structure and morphology changed while the linkage of FeO6 octahedral units was distorted. The FT-IR spectra revealed the formation of the Fe–O–Si bond in particles containing silicate ions, and the characteristic bond affects the local structure and morphology of the particles.

The effect of microstructure and purity on the native oxidation of Cu was studied by using angle-resolved X-ray photoelectron spectroscopy (AR-XPS) and spectroscopic ellipsometry (SE). A high quality copper film prepared by ion beam deposition under a substrate bias voltage of −50 V (IBD Cu film at V s = −50 V) showed an oxidation resistance as high as an ultra high purity copper (UHP Cu) bulk, whereas a Cu film deposited without substrate bias voltage (IBD Cu film at V s = 0 V) showed lower oxidation resistance. The growth of Cu 2 O layer on the UHP Cu bulk and both types of the films obeyed in principle a logarithmic rate law. However, the growth of oxide layer on the IBD Cu films at V s = 0 and −50 V deviated upward from the logarithmic rate law after the exposure time of 320 and 800 h, respectively. The deviation from the logarithmic law is due to the formation of CuO on the Cu 2 O layer after a critical time.

Fine particles of corrosion products consisting of one kind of ferric oxyhydroxide, either γ-FeOOH (lepidocrocite) or α-FeOOH (goethite), were directly prepared by dipping pure iron into aqueous solutions containing sodium chloride, sodium sulfate, or their mixed salts with sodium bicarbonate. Quantitative X-ray structural analysis using an in-house X-ray diffraction apparatus has been used for characterizing the atomic-scale structure of these ferric oxyhydroxide particles. The morphology of the γ-FeOOH and α-FeOOH particles was observed by transmission electron microscopy (TEM), and their bonding structures were analyzed using Fourier transform infrared spectroscopy (FT-IR). The realistic atomic-scale structures in the γ-FeOOH and α-FeOOH particles were estimated by fitting the interference functions with the help of the reverse Monte Carlo (RMC) simulation technique. The results showed that the linkages of fundamental FeO 6 octahedral units in the particles were deviated from the ideal crystal structure. The structural deviation is believed to be due to the incorporation of foreign anions during the formation of these particles in the aqueous solutions. The resultant atomic-scale structures in the γ-FeOOH and α-FeOOH particles were correlated with their morphology and bonding structure.

In order to find the optimum conditions to obtain copper–nickel–silicon (Cu–Ni–Si) alloys with high strength and high electrical conductivity, the aging characteristics of micro-Vickers hardness and electrical resistivity of different Cu–Ni–Si alloys were systematically measured at room temperature. The alloys were isochronally or isothermally aged after solution treatment. The effects of cold rolling after solution treatment as well as the alloy composition on the hardness and resistivity were studied. The results show that there appears to be an optimum composition ratio of nickel to silicon for obtaining high strength and high electrical conductivity, and cold rolling after solution treatment is effective in increasing the strength and electrical conductivity. The addition of a small amount of iron to the copper base alloys appears to improve these above-mentioned properties. A multi-step aging process coupled with cold rolling was proposed for realizing Cu–Ni–Si alloys with high strength and high electrical conductivity. The mechanism of precipitation in cold-rolled alloys was discussed on the basis of the results obtained.

Quantitative X-ray structural analysis by applying anomalous X-ray scattering (AXS) has been used for characterizing the effect of chromium on the atomic-scale structure of α-FeOOH particles, which is a typical ferric oxyhydroxide in rust formed on the steel surface. The X-ray diffraction profiles showed that the fundamental structure of α-FeOOH containing chromium is similar to that of α-FeOOH particles without chromium. The realistic atomic-scale structures in α-FeOOH with and without chromium were estimated by fitting both the ordinary and environmental interference functions with model calculation using the reverse Monte Carlo (RMC) simulation technique. The results indicated that distortion of the linkage of FeO 6 octahedral structural units in α-FeOOH is induced by chromium addition, but chromium addition to α-FeOOH fundamentally is likely to be substituted for iron in α-FeOOH. The atomic-scale arrangements in α-FeOOH with and without chromium were visualized using FeO 6 octahedral units. These middle range ordering structures were correlated with the microscopic morphological change of particles by chromium addition.

Quantitative X-ray structural analysis coupled with anomalous X-ray scattering has been used for characterizing the atomic-scale structure of rust formed on steel surfaces. Samples were prepared from rust layers formed on the surfaces of two commercial steels. X-ray scattered intensity profiles of the two samples showed that the rusts consisted mainly of two types of ferric oxyhydroxide, {alpha}-FeOOH and {gamma}-FeOOH. The amounts of these rust components and the realistic atomic arrangements in the components were estimated by fitting both the ordinary and the environmental interference functions with a model structure calculated using the reverse Monte Carlo simulation technique. The two rust components were found to be the network structure formed by FeO{sub 6} octahedral units, the network structure itself deviating from the ideal case. The present results also suggest that the structural analysis method using anomalous X-ray scattering and the reverse Monte Carlo technique is very successful in determining the atomic-scale structure of rusts formed on the steel surfaces.

Quantitative X-ray structural analysis coupled with reverse Monte-Carlo (RMC) simulation and infrared spectroscopy have been used for characterizing the atomic scale structure in α-FeOOH particles with and without anions consisting mainly of carbonate. The results showed that these α-FeOOH particles fundamentally have the α-FeOOH structure, but the linkages of FeO6 octahedral structural units in the α-FeOOH particles with the anions are significantly distorted, and the distortion appears to be related with the anions in the α-FeOOH particles. As α-FeOOH are formed through olation and oxolation of iron complexes described by FeO6 structural units with hydrogen in aqueous solution, the atomic scale structure in the α-FeOOH particles may be influenced by anions.