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The local electronic state of the N,N,N',N'-tetraglycidyl-4,4′-diaminodiphenylmethane epoxy resin cured with 4,4′-diaminodiphenylsulfone (TGDDM-DDS), one of model adhesive materials, was investigated by the O K-edge X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES). The total-electron-yield XAS spectra for TGDDM-DDS as a function of the X-ray dose exhibit the exponential-like decrease in the curing-derived pre-edge intensity due to the radiation damage. The quantitative analysis on the pre-edge intensity with respect to the X-ray dose enables the determination of the critical absorbed dose for the chemical change on TGDDM-DDS as 3.83 ± 0.01 MGy at 300 K. By using resonant XES with the well-focused X-ray beam, we found that (i) the charged-particle equilibrium exists for the soft X-rays in the range of at least 0.001–0.847 mm2 beam spot and that (ii) the half of the critical absorbed dose can be regarded as the limit indicator for the non-destructive chemical-state characterization on resinous adhesive materials and interfaces using soft X-rays.

An ultrafast atomic motion of a photo-induced coherent phonon of bismuth at low temperatures was directly observed with time-resolved x-ray diffraction. A cryostat with a window that is transparent to both optical lasers and x rays enabled versatile diffraction measurements in a wide temperature range including below 10 K. It is found that an atomic displacement in a fully symmetric A1g phonon mode is suppressed at low temperatures. This result indicates that the displacive excitation process is suppressed in the phonon generation with the decrease in temperature.

Ni(25 nm)/Cu(25 nm)/Cr(25 nm) thin films were deposited by DC magnetron sputtering at room temperature onto Si(100) single-crystal substrates and irradiated by low-energy Ar+ ions in the energy range of 400 - 2000 eV with fluences of 1.41016 - 1.11017 ion/cm2. Influence of the ion bombardment on the structural properties, surface morphology and chemical composition was investigated using XRD, AFM, SEM, AES, XPS, SIMS and SNMS techniques. It was found that the low-energy ion bombardment does not lead to phase composition modifications, but causes reduction of Ni layer crystallites size. Optimal bombardment mode (energy 800 eV, fluence 5.61016 ion/cm2), providing reduction of impurities amount in all three layers of the stack without diffusion intermixing between main components, was determined. Calculated coefficients of internal layers passivation are in good agreement with found increase of Cr and Cu layers thicknesses due to the reduction processes. New model of reduction processes taking into account the long-range effect was proposed.

X-ray free-electron lasers (XFELs) provide intense (∼1012 photons per pulse) coherent X-rays with ultra-short (∼10−14 s) pulse lengths. X-rays of such an unprecedented nature have introduced new means of atomic scale structural investigations, and discoveries are still ongoing. Effective use of XFELs would be further accelerated on a highly adaptable platform where most of the new experiments can be realized. Introduced here is the multiple-application X-ray imaging chamber (MAXIC), which is able to carry out various single-pulse diffraction experiments including single-shot imaging, nanocrystallographic data acquisition and ultra-fast pump–probe scattering for specimens in solid, liquid and gas phases. The MAXIC established at the SPring-8 ångström compact free-electron laser (SACLA) has demonstrated successful applications in the aforementioned experiments, but is not limited to them. Also introduced are recent experiments on single-shot diffraction imaging of Au nanoparticles and serial crystallographic data collection of lysozyme crystals at SACLA.

Single-shot imaging using femtosecond x-ray pulses from x-ray free electron lasers (XFELs) has revealed high-resolution structures of Au nanoparticles and biological macromolecular complexes. The x-ray pulse power of 10 GW is enough to vaporize specimen when it is focused on a few microns area. This makes it essential to have a single particle loader to provide fresh samples to the x-ray pulses. In this paper we introduce single-shot imaging at Spring-8 Angstrom Compact Free Electron Laser (SACLA) to investigate various types of specimen, from metallic nanoparticles to biological macromolecules, prepared on Si3N4 membrane. A significant reduction in sample consumption is achieved while maintaining a data acquisition rate of 30 Hz, which is compatible with the current SACLA operation rate.

An automated spectrofluorometer system utilizing an on-line minicomputer is described. This system primarily consists of a commercial spectrofluorometer, a minicomputer and simple peripherals. Attractive features of this system lie in the fact that the rapid collection of the absolute spectra is carried out by using correction factors derived from the results of absolute intensity measurement by means of a quantum counter. During the standardization process for the spectral correction, two individual monochromators in the instrument can be precisely synchronized like a double-monochromator with the assistance of the computer. Details of the system are presented with the results of its performance test.