Super Photon Ring Research Articles

Microembolization effects of imipenem/cilastatin in vivo Depicted by Monochromatic Synchrotron X-ray Microangiography

PurposeTo elucidate the characteristics of imipenem/cilastatin (IPM/CS) as an embolic material in microvessels in vivo. Materials and MethodsThree healthy rabbits were injected subcutaneously in one auricle with picibanil in advance to create an inflammation-induced neovascular model. Microangiography was performed using monochromatic X-rays obtained from a large synchrotron radiation facility (super photon ring-8; SPring-8). All rabbits underwent pre-embolization microangiography under anesthesia. Embolization from the central branch of the auricular artery was then performed using a mixture of IPM/CS (0.2 g) + non-ionic contrast medium (2 ml). Microangiography was performed immediately after and at 10, 20, 30, 40, 50, 60, 70, 80, and 90 minutes after embolization. The diameter of embolized vessels was measured from the images immediately after embolization. Recanalization times were evaluated from the post-embolization to 90 minutes after embolization, and they were compared between normal sites and sites where inflammation was induced. ResultsThe mean diameter of the embolized vessels immediately after embolization evaluated at the normal site was 267 ± 58.35 (range: 174-363) μm. Evaluation of post-embolization recanalization showed that vessels in the normal sites recanalized after a mean of 70 (range 50-70) min, whereas vessels at the sites of inflammation did not recanalize in observations up to 90 minutes after embolization. ConclusionsThis study characterized IPM/CS as an in vivo embolic substance and the duration of the embolic effect differed between normal and inflamed sites. Clinical Relevance/ApplicationIPM/CS exhibited an ultra-short embolic effect not seen with existing embolic materials and may have a long embolic effect specific to inflamed vessels rather than normal vesseles. This characteristic could contribute to the indications for embolization being expanded to new diseases, such as embolization for pain relief in chronic joint pain.

Operando Analysis of Bi/BiF3 Electrode Reaction in Li+/F- Hybrid Electrolyte By Synchrotron Radiation Diffraction

1.IntroductionIn recent years, the development of innovative batteries that exceed the performance of lithium-ion batteries has been desired. One of the candidates is a fluoride shuttle battery (FSB). It is an anion-based, rechargeable batteries operating under fluoride shuttling, and rests upon the foundation of a redox-active fluoride ion transporting electrolyte of high electrochemical stability. To realize the FSB, we have developed a lactone-based Li+/F- hybrid electrolyte, in which Li+ and F- ions that normally cannot coexist in organic solvents form some complexes soluble in GBL. The thus reformed electrolyte, together with its delicate and unique anion accepting (AA) function, largely expands the negative potential window to or beyond the standard redox potential of Li+/Li. In this study, in order to clarify the electrochemical behaviors of BiF3/Bi electrode combined with the electrolyte, the operando analysis was carried out by the synchrotron radiation diffraction (SRD) measurement.2. ExperimentalThe BiF3 powder mixed with acetylene-black and PVdF was used as the working electrode. The activated carbon and Ag metal were used as the counter and reference electrodes, respectively. The Al-laminated half-cell composed of above-mentioned electrodes was assembled using a newly developed hybridized electrolyte. Thus prepared cell was pre-discharged (0th cycle) in advance in the potential range of -1.5 V – 1.0 V at ca. 0.04C. Then, several charge/discharge cycles were repeated with the same conditions. SRD was measured with BL28XU beam line at Super Photon ring-8, Japan during the whole charge/discharge process. High-energy X-ray with a wavelength of 0.049592 nm was used to obtain 2D diffraction patterns. The exposure time was set to 10 s, and several thousand diffraction profiles were obtained during the discharge/charge process. In order to analyze the obtained enormous profiles data in conjunction with the charge/discharge curves and their differential curves (V-dQ/dV), an analysis software called “Profile Chaser” was newly developed. By using the software, all the profiles of electrode during charge/discharge processes are loaded automatically in the computer. The profiles were successively displayed on a monitor as a series of profiles in conjunction of compositions estimated from the charge/discharge curves, so that the profile change was traced from the monitor.3. Results and discussionsFig.1 shows the SRD profile changes in the discharge process of 0th and 1st cycles. In both cycles, the intensity of 111 diffraction of BiF3 decreased and that of 012 diffraction of Bi increased as the discharge reaction proceeded. However, the formation of BiF3 was hardly observed in the charge process. It indicates that the bismuth fluoride formed in the charge process is amorphous or solved in the electrolyte. Figure 1

Methods and application of coherent X-ray diffraction imaging of noncrystalline particles.

Microscopic imaging techniques have been developed to visualize events occurring in biological cells. Coherent X-ray diffraction imaging is one of the techniques applicable to structural analyses of cells and organelles, which have never been crystallized. In the experiment, a single noncrystalline particle is illuminated by an X-ray beam with almost complete spatial coherence. The structure of the particle projected along the direction of the beam is, in principle, retrieved from a finely recorded diffraction pattern alone by using iterative phase-retrieval algorithms. Here, we describe fundamental theory and experimental methods of coherent X-ray diffraction imaging and the recent application in structural studies of noncrystalline specimens by using X-rays available at Super Photon Ring of 8-Gev and SPring-8 Angstrom Compact Free Electron Laser in Japan.

Crystal rotation and microstructures in an aluminum single-slip system under tensile loading

We experimentally investigated the rotation angle of the (220) plane in an aluminum single-slip system in which the angles of 〈110〉 and 〈111〉 in the single crystal were 45° relative to the tensile loading direction. Crystal rotation was investigated at several spots (50 × 50 μm) along 〈110〉 and 〈111〉 using synchrotron radiation white X-rays at the BL28B2 beamline of super photon ring-8. In measurements along the 〈110〉 axis, at an applied strain of ε = 5%, the relative crystal rotation of (220) in the vertical plane increased from 0.850° to 5.438° in the range of 0.9 to 1.4 mm. We observed the microstructure using a transmission electron microscope and verified the size of the dislocation cells or subgrains at each spot along 〈110〉. The fundamental local crystallography revealed in this work should be helpful in establishing a method for evaluating ductile damage in materials.

In-situ X-ray diffraction during tensile deformation of ultrafine-grained copper using synchrotron radiation

At the synchrotron facility, Super Photon Ring – 8 GeV, in-situ X-ray diffraction during tensile deformation was conducted on ultrafine-grained Cu with a grain size of about 300 nm fabricated by equal-channel angular pressing. The diffraction profile was observed with the time resolution of about 1 s using multiple MYTHEN detectors, and the diffraction angle and the full-width at half-maximum of some Bragg peaks were determined using the pseudo-Voigt function. From the analysis of Bragg peaks, it was found out that there are microscopically three regions; elastic, plastic and transition regions. The 0.2% proof stress obtained from the stress–strain curve locates within the microscopic transition region. Microstrain was evaluated using the Williamson–Hall method and the dislocation density was also obtained from the microstrain. The dislocation density starts increasing before 0.2% proof stress, which is associated with dislocation bow-out and emission from grain boundaries. The Taylor relationship seems to be still satisfied after 0.2% proof stress.

高輝度放射光ラミノグラフィを用いた転動疲労き裂発生および進展挙動に及ぼす介在物配向の影響

In rolling contact fatigue (RCF), cracks initiate and propagate from inclusions beneath the surface. In the present study, crack propagation behavior under RCF was observed by laminography using ultra-bright synchrotron radiation, which is suitable for thin plates, at SPring-8 (Super Photon Ring - 8 GeV). The material had intentionally contains a high concentration of sulfur to enable the observation of crack initiation from MnS inclusion. Fatigue tests were interrupted to conduct laminography by a new developed compact RCF test machine. It was found that vertical cracks, whose face was perpendicular to the rolling direction, were first appeared, then horizontal cracks, those faces were parallel to the sample surface were formed after the vertical crack propagated. And then flaking occurred as the result of the propagation of the horizontal crack. The initiation life of the vertical cracks and horizontal cracks depended on the length and width of the MnS inclusions. And it is considered that the vertical crack is an important factor of flaking life. These mechanisms of flaking process, which was directly observed by laminography using synchrotron radiation, were completely different from conventional RCF mechanism supposed from the surface observations by conventional microscopies.

Abstract 11103: Increase of Oxidative Stress Precipitated by Selenium Deficiency Plays a Role in Cardiac Hypofunction in Uremic Cardiomyopathy

Introduction: Various trace elements are deficient in hemodialysis patients, but the relationship of such deficiencies with cardiac hypofunction is unclear. We examined the deficiencies of trace elements in the blood and hair of hemodialysis patients diagnosed with uremic cardiomyopathy and investigated cardiac hypofunction mechanism from myocardial tissue. Methods: Using blood samples, we measured 25 elements including Se, Mn, Cu, and Zn by high-resolution inductively coupled plasma (ICP) mass spectrometry and ICP emission spectral analysis. We also compared glutathione peroxidase (GSHPx) activation and radical formation potential between the uremic cardiomyopathy patient group (n = 22) and a control group with normal cardiac function (n = 30). Using myocardial tissue, we assessed the exacerbation of oxidative stress by 8-hydroxy-2-deoxyguanosine, 4-hydroxy-2-nonenal, and GSHPx staining and microcirculatory disorder by the perivascular fibrosis area ratio (PVFR). We also measured concentrations of elements in hair at the Super Photon ring-8 GeV (SPring-8) facility. Results: Compared with the control group patients, the uremic cardiomyopathy patients had lower selenium (99.7 ± 21.4 vs. 146 ± 23.3 ng/ml, p < 0.00001) and manganese concentrations (0.39 ± 0.15 vs. 0.60 ± 0.12 ng/ml, p < 0.001); they also showed decreased activation of GSHPx (121 ± 33 vs. 328 ± 44 μmol/min/L, p < 0.00001), an antioxidant enzyme involving selenium, with only selenium concentration correlating to left ventricular ejection fraction (p = 0.0009). Oxidative stress marker staining, radical formation potential in serum, and PVFR were all augmented in the uremic cardiomyopathic patients (p < 0.001). Conclusions: Selenium concentration decrease in the serum of hemodialysis patients may reflect a decrease in GSHPx activation, increasing oxidative stress, and precipitating a coronary microcirculatory disorder involved in the cardiac hypofunction seen in uremic cardiomyopathy.

4D evaluation of grain shape and fatigue damage of individual grains in polycrystalline alloys by diffraction contrast tomography using ultrabright synchrotron radiation

A three dimensional grain mapping technique for polycrystalline materials, called X-ray diffraction contrast tomography (DCT), was developed at SPring-8 (Super Photon ring – 8GeV), which is the brightest synchrotron radiation facility in Japan, and the measurement conditions and data acquisition procedure are discussed. The developed technique was applied to a commercially pure aluminum, commercially pure iron, and austenitic stainless steel. The shape and location of grains could be determined by DCT using the apparatus in a bending beam line of SPring-8. To evaluate the dislocation structure in tensile tests and fatigue tests, the rotation angle spread of individual grains was measured. The rotation angle spread is caused by mosaicity, which is related to the dislocation structure in a grain. The rotation angle spread was found to increase with increasing plastic strain. Fatigue damage could also be evaluated from the rotation angle spread obtained by DCT measurement.

OS0804-301 高輝度放射光ラミノグラフィを用いた転動疲労き裂の発生および進展過程の観察

In rolling contact fatigue (RCF), cracks initiate and propagate from inclusions beneath the surface. In the present study, crack propagation behavior under RCF was observed by synchrotron radiation computed laminography (SRCL), which is suitable for thin plates, in SPring-8 (Super Photon Ring-8 GeV). Specially fabricated inclusion-rich steel (modified JIS SUJ2) plate specimen, which includes extended inclusions distributed in depth direction, was employed in the experiments. Specimen with surface crack from inclusion and after the occurrence of flaking was observed by SRCL, and flaking defect and crack under the surface was successfully detected. It was found that the tensile-type vertical crack, which was perpendicular to the rolling contact surface, was formed from a cylindrical inclusion. After the vertical crack propagated along inclusion, the shear-type horizontal crack, which was parallel to the rolling contact surface, was found to initiate and then flaking occurred as the result of the propagation of the shear-type crack. It is considered that the vertical crack is an important factor of flaking process and crack propagation behavior under RCF from inclusions is clarified by SRCL.

Invited; Synchrotron Radiation Based X-ray Microdiffraction of Advanced Semiconductor Materials

X-ray diffraction (XRD) has been recognized as a well-established method by which lattice structures of crystalline materials can be clarified precisely. High penetrating power of X-ray allows us to reveal inner structures and buried interfaces usually implemented in materials and devices. Conventional XRD with a typical probe size of over 100 μm clarifies only averaged structures having good statistics without any untypical ones, known as ensemble average[1]. However, in general, the property and the performance of materials and devices become governed by the localized specific structures when miniaturized to a nanometer scale. In such a case, an X-ray beam with a probe size much smaller than the conventional one is truly required.X-ray microdiffraction (XRMD) is one of the most effective methods to establish both the advantages of XRD analysis and high special resolution to exceed the ensemble average analysis. The state-of-the-art XRMD system at the beam line of the synchrotron radiation facility, Super Photon ring 8 GeV (SPring-8), in Japan, realizes an X-ray probe with a size of a few hundred nanometer [2]. Thus XRMD gives us precise and rich information especially on the crystalline texture and the local strain distribution on a submicron scale.1. Crystallinity of Ge thin linesLine-shaped Ge films with nanometer-sized widths on Si substrates are promising for applying to next generation three dimensional high-mobility channels in metal-oxide-semiconductor field effect transistors. One of the concerns is the introduction of threading dislocations in the Ge films; 60° dislocations critically alter the crystallinity of Ge films. Aspect ratio trapping with the use of selective epitaxy of Ge on SiO2-patterned Si substrates is one of effective ways to reduce threading dislocations in Ge thin line channels [3]. However, there is insufficient understanding of strain relaxation and local structures in the Ge thin lines with such anisotropic geometry.XRMD has been employed to investigate the crystallinity of the line-shaped Ge films with line widths of 100-1000 nm [4]. It has been revealed that crystal domains with a size of about 100 nm in the Ge thin lines were tilted at different angles within the range of 0.6 degree. The tilt angle range was larger in thinner Ge lines after the growth and reduced by annealing for all line widths. The domaining was found to be mostly caused by the introduced 60° dislocations. The formation of a single large domain with a specific tilt angle was also achieved near the surfaces of Ge thin lines with widths of 100 and 200 nm, which was attributed to the suppression of threading dislocation formation by the SiO2side walls.2. Local strain mapping for AlN thick filmsAlN with a 6.2-eV-wide bandgap is potentially prospective as a substrate material for deep ultraviolet optoelectronics devices. Due to the lack of bulk AlN crystals, thick film growth with hydride vapor phase epitaxy is known to be promising for the production of large scale AlN wafers. Crystalline quality of AlN films directly grown on α-Al2O3substrates is poor with high dislocation density and residual strain due to lattice and thermal mismatches. In contrast, epitaxial lateral overgrowth using trench-patterned templates was proven to be effective in obtaining high-quality films [5].Local strain distribution in thick AlN films grown on a periodic trench-patterned AlN/α-Al2O3template (see Fig. 1(a)) has been investigated by XRMD [2]. Figure 1(a) reveals nanometer-scale voids that form tunnels in the AlN film and are periodically arranged at 6-µm-intervals corresponding to the periodicity of trench pattern. XRMD experiment with the X-ray incidence into the cross-sectional plane of sample (see Fig. 1(b)) was conducted for taking reciprocal space maps (RSMs) from the two-dimensional (2D) scan area at 1- and 2-μm intervals in the X and Z axes, respectively. 2D distribution maps of strains along the Z and X directions obtained from the RSMs are shown in Figs. 2(a) and 2(b), respectively. It should be noticed that both strains are considerably relaxed around the void region, as illustrated in Fig. 2(c). This result demonstrates that XRMD clearly discloses the local strain distribution in the thick AlN film and the voids are effective in relaxing the strain induced during the growth process.

Effect of Composition Ratio on Erbium Silicide Work Function on Different Morphology of Si(100) Surface Changed by Alkaline Etching

Effect of Composition Ratio on Erbium Silicide Work Function on Different Morphology of Si(100) Surface Changed by Alkaline Etching

OS1307 放射光μCTイメージングを用いたTi-6Al-4V内部に発生する微小疲労き裂の検出

Very high cycle fatigue is mainly characterized by sub-surface fracture in the long regime over 10^7-10^8 cycles. However, since the detection of internal cracks is extremely difficult, the mechanism of very high cycle fatigue has not been clarified yet. In recent researches, small internal inclusions in steel were detected by using synchrotron radiation μCT imaging in the Super Photon ring-8 GeV (SPring-8). These results suggest a possibility that small cracks initiating inside metal material are observable. Focusing on the possibility, the present work conducted non-destructive observations of internal cracks by using the X-rays μ CT imaging in SPring-8 on Ti-6Al-4V alloy m which fatigue damage was accumulated. In order to open the internal crack during observations, a tensile load was given to the specimen. As a result of the series of observations, small internal fatigue cracks with a size of about 30 μm were successfully detected under the optimum tensile load necessary to open and identify those cracks. In addition, it was revealed that multi-cracks initiated inside the specimen and the fatigue life was determined by the competition of those propagations. The results obtained in this study showed that non-destructive inspection technique to detect small internal fatigue cracks was established.

Lifetime of the unpaired electron species in calf thymus DNA thin films induced by nitrogen and oxygen K-shell photoabsorption

Purpose: To study the lifetime of the short-lived unpaired electron species induced in a calf thymus DNA film by soft X-rays in the energy regions around nitrogen and oxygen K-edge.Materials and methods: Dry calf thymus DNA films were measured by electron paramagnetic resonance (EPR) spectrometer during the monochromatic soft X-ray irradiation provided from a synchrotron accelerator (SPring-8, Super Photon ring-8 GeV). Two operation modes of SPring-8 with different electron bunch structures were used to explore dependence of EPR intensity on pulse interval of soft X-rays.Results: Observed EPR spectra did not show significant difference, in the spectral shape, intensity, g-factor and photon energy dependence, between the two bunch modes.Conclusions: The total yield of the unpaired electron species were estimated by assuming the exponential relaxation of the unpaired electrons with two different bunch modes of the synchrotron. The lifetime of the unpaired electron species is estimated to be in the range of a few tens to several hundreds of μs.

Detection and visualisation of elemental components in various ambient species by synchrotron microbeam technique

This study introduces the application of the synchrotron radiation induced X-ray fluorescence (SR-XRF) microprobe installed at the Super Photon ring-8 GeV (SPring-8), which is the world's largest third-generation synchrotron radiation facility, to the specification of chemical properties of various atmospheric samples. The combination of visual elemental mapping and XRF spectral analyses allows for the interpretation of the nature and composition of individual particles. Individually collected droplets by the replication technique were also irradiated by X-ray microbeam to carry out visual reconstruction of elemental maps for their multiple components. The multielemental peaks corresponding to X-ray energy were also successfully resolved. Because the chemical contents of solute for individual droplets can be definitely clarified in this study, we can describe the mechanisms involved in droplet formation and pollutant scavenging. The point analysis of sand dust collected from the local desert in China confirmed that the fine fragments of sand, which may be lifted and transported over a long distance, are considerably inhomogeneous in elemental component.

Demonstration of osmotically dependent promotion of aerenchyma formation at different levels in the primary roots of rice using a ‘sandwich’ method and X-ray computed tomography

The effect of environmental factors on the regulation of aerenchyma formation in rice roots has been discussed for a long time, because aerenchyma is constitutively formed under aerated conditions. To elucidate this problem, a unique method has been developed that enables sensitive detection of differences in the development of aerenchyma under two different environmental conditions. The method is tested to determine whether aerenchyma development in rice roots is affected by osmotic stress. To examine aerenchyma formation both with and without mannitol treatment in the same root, germinating rice (Oryza sativa) caryopses were sandwiched between two agar slabs, one of which contained 270 mm of mannitol. The roots were grown touching both slabs and were thereby exposed unilaterally to osmotic stress. As a non-invasive approach, refraction contrast X-ray computed tomography (CT) using a third-generation synchrotron facility, SPring-8 (Super photon ring 8 GeV, Japan Synchrotron Radiation Research Institute), was used to visualize the three-dimensional (3-D) intact structure of aerenchyma and its formation in situ in rice roots. The effects of unilateral mannitol treatment on the development of aerenchyma were quantitatively examined using conventional light microscopy. Structural continuity of aerenchyma was clearly visualized in 3-D in the primary root of rice and in situ using X-ray CT. Light microscopy and X-ray CT showed that the development of aerenchyma was promoted on the mannitol-treated side of the root. Detailed light microscopic analysis of cross-sections cut along the root axis from the tip to the basal region demonstrated that aerenchyma developed significantly closer to the root tip on the mannitol-treated side of the root. Continuity of the aerenchyma along the rice root axis was morphologically demonstrated using X-ray CT. By using this 'sandwich' method it was shown that mannitol promoted aerenchyma formation in the primary roots of rice.

Application of Synchrotron Radiation X-Ray Microtomography to Nondestructive Evaluation of Thermal Fatigue Process in Flip Chip Interconnects

New nondestructive inspection methods with high spatial resolution are expected to support the evaluation and enhancement of the reliability of microjoints on printed circuit boards. An X-ray microtomography system, the SP-μCT has been developed at the Super Photon ring-8 GeV (SPring-8), the largest synchrotron radiation facility in Japan. In this work, the SP-μCT was first applied to the nondestructive evaluation of thermal fatigue phenomena, namely microstructure evolution (i.e., phase growth) and microcrack propagation, appearing in actual solder microbumps of flip chip interconnects due to thermal cyclic loading. In addition, a refraction-contrast imaging technique was simultaneously applied to visualize the fatigue cracks with an actual opening of less than 100 nm. The observed specimen has a flip chip structure joined by Sn-37wt%Pb eutectic solder bumps 150 μm in diameter. Consequently, the process of phase growth and crack propagation was determined via observation of consecutive computed tomography (CT) images obtained in the same plane of the same specimen. As the thermal cycle proceeded, remarkable phase growth was clearly observed, followed by the appearance of fatigue cracks in the corners of the interfaces between the solder bump and Cu pad. Moreover, the CT images also enabled us to evaluate the fatigue lifetime of the bumps, as follows. The lifetime to fatigue crack initiation was estimated by quantifying the increase in the phase growth. The crack propagation lifetime to failure was then determined by measuring the average crack propagation rate. Such results have not been obtainable at all by X-ray CT systems for industrial use and demonstrate the possibility of nondestructive inspection by a synchrotron radiation X-ray microtomography system.

Preliminary Study on the Visualization and Quantification of Elemental Compositions in Individual Microdroplets using Solidification and Synchrotron Radiation Techniques

Quantifying the solute composition of a cloud droplet (or a whole droplet) is an important task for understanding formation processes and heating/cooling rates. In this study, a combination of droplet fixation and SR-XRF microprobe analysis was used to visualize and quantify elements in a micro-scale droplet. In this study, we report the preliminary outcome of this experiment. A spherical micro-scale droplet was successfully solidified through exposure to α-cyanoacrylate vapor without affecting its size or shape. An X-ray microprobe system equipped at the beam line 37XU of Super Photon ring 8 GeV (SPring-8) was applied to visualize and quantify the elemental composition in an individual micro-scale droplet. It was possible to reconstruct 2D elemental maps for the K and Cl contained in a microdroplet that was dispensed from the 10-ppm KCl standard solution. Multi-elemental peaks corresponding to X-ray energy were also successfully resolved. Further experiments to determine quantitative measures of elemental mass in individual droplets and high-resolution Xray microtomography (i.e., 3D elemental distribution) are planned for the future.

In vivo analysis of metal distribution and expression of metal transporters in rice seed during germination process by microarray and X-ray Fluorescence Imaging of Fe, Zn, Mn, and Cu

To investigate the flow of the metal nutrients iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) during rice seed germination, we performed microarray analysis to examine the expression of genes involved in metal transport. Many kinds of metal transporter genes were strongly expressed and their expression levels changed during rice seed germination. We found that metal transporter genes such as ZIP family has tendency to decrease in their expressions during seed germination. Furthermore, imaging of the distribution of elements (Fe, Mn, Zn, and Cu) was carried out using Synchrotron-based X-ray microfluorescence at the Super Photon ring-8 GeV (SPring-8) facility. The change in the distribution of each element in the seeds following germination was observed by in vivo monitoring. Iron, Mn, Zn, and Cu accumulated in the endosperm and embryos of rice seeds, and their distribution changed during rice seed germination. The change in the patterns of mineral localization during germination was different among the elements observed.

Half-life of theHo164by the (γ,n) reaction from laser Compton scatteringγrays at the electron storage ring NewSUBARU

The half-life of an isomer in $^{164}\mathrm{Ho}$ was measured by using photodisintegration reactions. The photons were generated by Compton scattering of laser photons and relativistic electrons at the electron storage ring NewSUBARU in the super photon ring 8-GeV (SPring-8) facility. The half-life is $36.4\ifmmode\pm\else\textpm\fi{}0.3$ min. This value is about 3% shorter than the previous value $37.{5}_{\ensuremath{-}0.5}^{+1.5}$ min reported in 1966.

Residual Stress Analysis in Lanthanum Gallate-Based Cells before and after Fuel Cell Operation

The distribution of residual stress in cells with the practical size of 120 mm diameter was measured by X-ray diffraction utilizing synchrotron radiation at Super Photon ring 8 GeV (SPring-8). The residual stress was determined by the constant penetration depth method. When NiO–samaria-doped ceria (SDC) was sintered on (LSGMC), the tensile stresses resided in NiO and SDC, and the compressive stress resided in LSGMC. The reduction of the anode by hydrogen decreased tensile stresses in the anode. The residual stresses in the electrodes did not change at any X-ray penetration depth. The sintering of the cathode slightly affected the residual stresses of the cells.