Search Results (27)

A lens-coupled high-speed X-ray camera, “Hayaka”, was developed for quick imaging of X-ray absorption fine structure (XAFS) and time-resolved high-speed computed tomography (CT) using synchrotron radiation (SR). This camera is a lens-coupled type, composed of a scintillator, an imaging lens system, and a high-speed visible light sCMOS, capable of imaging with a minimum exposure time of 1 μs and a maximum frame rate of 5000 frames/s (fps). A feasibility study using white and monochromatic SR at the beamline BL07 of the SAGA Light Source showed that fine X-ray images with a spatial resolution of 77 μm can be captured with an exposure time of 10 μs. Furthermore, quick imaging XAFS, combined with high-speed energy scanning of a small Ge double crystal monochromator of the same beamline, enabled spectral image data to be acquired near the Cu K-edge in a minimum of 0.5 s. Additionally, an in coquendo 4DCT (time-resolved 3D observation of cooking processes) observation combined with a high-speed rotation table revealed the boiling process of Japanese somen noodles over 150 s with a time resolution of 0.5 s. Full article

The performance of synchrotron beamlines critically depends on the optimal coupling between the undulator and the monochromator. This work presents the implementation and quantitative characterization of a synchronized scanning system for the elliptically polarizing undulator (EPU) and the variable-line-spacing plane-grating monochromator at the BL07U beamline of the Shanghai Synchrotron Radiation Facility (SSRF). The system ensures that the monochromator’s narrow bandwidth dynamically tracks the brilliant central cone of the undulator radiation. A linear correlation between the monochromator energy and the undulator gap, justified theoretically for small scan ranges and reinforced by a robust real-time calibration procedure, forms the control basis. The automation is built upon a standard software stack comprising EPICS for device control, the Bluesky Suite for experimental orchestration, and Phoebus for the human–machine interface. Through comparative X-ray absorption spectroscopy (XAS) measurements at the Fe L_2,3-edges, the synchronized mode is shown to enhance beam brilliance by 37% and stabilize the incident flux, reducing its variation from 4.2% to 1.8%. This directly results in absorption spectra with superior lineshape fidelity, a 40% reduction in noise, and the elimination of pre- and post-edge artifacts, unequivocally isolating the synchronization effect. This advancement provides a stable, high-brilliance photon source essential for high-quality XAS and X-ray magnetic circular/linear dichroism (XMCD/XMLD) studies. Full article

This article provides information on the processing of chromium-containing waste from the Aktobe ferroalloy compounds plant using chemical reagents followed by high-temperature heat treatment for the synthesis of a composite chromite pigment used in the textile industry. This technology was developed for the first time for the purpose of recycling industrial waste and rational use of natural resources. The obtained pigments were analyzed by the X-ray phase of a D878-PC75-17.0 incident beam monochromator and the phase composition of the composite chromite pigment was studied. The thermogravimetric analysis of the composite chromite pigments was performed using a TGA/DSC 1HT/319 analyzer to determine the change in mass with time and temperature. According to the TGA results, the mass loss was determined to be 0.18% of the total mass. The elemental composition of the composite chromite pigment was determined using a JEOL JSM-6490 LV SEM device and the content of chromium oxide (Cr₂O₃) was determined, which reached up to 50%. The thermodynamic patterns of the processes occurring during the production of chromite pigments were studied using the integrated Chemistry software pack HSC-6. The results of testing printed and processed cotton and composite fabrics by the proposed method showed that the color fastness to washing and wet and dry friction is 4 points and the wear resistance assessment is 4860 and 6485 cycles, respectively. Composite chromite pigment based on technogenic wastes is recommended for use in various coloring compositions, including those used for printing on cotton and composite fabrics. Full article

A concept of a high throughput, user-friendly, versatile bending magnet beamline at the fourth-generation synchrotron radiation facility SKIF, currently being constructed in Koltsovo (a science town near Novosibirsk, Russia), is proposed. The beamline is designed to implement the conventional and most demanded synchrotron techniques: XAS (X-ray absorption spectroscopy); XRD (X-ray diffraction), both powder and single-crystal, including the in situ mode; and XRF (X-ray fluorescence analysis). The beamline is conceived to be as simple as possible, but it is multifunctional, being a base beamline for the education and training of students, future synchrotron users, and beamline scientists. A number of potential beamline optical layouts are modeled in the XRT (XRayTracer) program package. The resulting beam characteristics at the sample position are discussed. A monochromator model is proposed. Surface distortions and their influence on the rocking curve of the Si111 crystal due to incoming heat loads are realistically modeled. The optimum design of the station is defined. The range of crystalline objects that are possible to be studied at the proposed station is emphasized, and future perspectives are outlined. Full article

As an alternative to rigid anodes, a novel concept of X-ray targets consisting of a stream or a multitude of streams of fast tungsten microparticles has recently been proposed. Low-density microparticle streams resemble thin targets with nearly constant intensity distribution over a wide range of photon energies, abruptly terminating at the Duane–Hunt limit of maximum photon energy instead of falling off smoothly. According to our simulations, fast microparticles outperform classical rigid targets and enable extremely high electronic input power density and X-ray output. This opens new possibilities for generating high-intensity, nearly monochromatic X-rays. Such keV-type X-ray sources could replace expensive electron synchrotrons in appropriate applications. Furthermore, for sufficiently thin microparticle streams, the output X-ray spectra are functions of particle size, allowing modulation of the mean photon energy. We simulated the spectral response of tungsten microparticles using Monte Carlo methods and confirmed the validity of our new concept to generate near-monochrome spectra and high intensity with microparticle-based X-ray sources, outperforming classical X-ray tubes. Furthermore, we confirm a weak size dependence of the mean energies of filtered X-rays. We complement previous results highlighting the advantages of microparticle-based X-ray targets and aim at the implementation of the new concept in the future. Full article

The article describes the results of an investigation to determine the values of radiation intensities emitted by O-, Cl-, Br-, and I-containing liquid spray targets in absolute units in the wavelength range 10–20 nm when excited by pulsed laser radiation. The conversion coefficients of laser radiation into the EUV radiation are given for some wavelengths. The authors’ specially designed pulse extrusion liquid supply system was used to form the liquid spray targets. An Nd:YAG laser with λ = 1064 nm, τ = 8.4 ns, and E_pulse = 0.8 J was used to excite the targets. Spectral measurements were made using a grazing incidence grating spectrometer–monochromator. The absolute intensities of a number of emission lines were also measured using a Bragg spectrometer based on a Mo/Be multilayer X-ray mirror, calibrated by both sensitivity and wavelength. The high values of absolute intensities of the liquid targets in the extreme ultraviolet wavelength range were demonstrated. Full article

In the present study an archaeometry programme has been developed on a limited number of coarse wares, monochrome, and bichrome glazed ceramics retrieved in the cities of Évora, Mértola, and Silves, located in Western Iberia, Portugal (Gharb al-Andalus during the Islamic period). The goals were to shed light on glazed ceramics provenance, technology, trading, and on the glaze technology applied. For this purpose, a multi-analytical approach was employed to characterize ceramic pastes and glazes using optical microscopy (OM), X-ray diffraction (XRD), X-ray fluorescence (XRF), and a Scanning Electron Microscope coupled to an Energy Dispersive Spectrometer (SEM-EDS). Results evidenced that over the Islamic rule, coarse wares were locally produced at Évora. On the contrary, monochrome and bichrome glazed ceramics were imported from the city of Silves, Mértola, and from unidentified workshops, probably located in southern Iberia. The analysis of decorations evidenced that despite the provenance of the samples, the glaze technology applied was rather uniform over time, depicting a widespread technological transfer in the al-Andalus. Full article

This paper deals with the simulation of output beam parameters of the inverse Compton X-ray Source (ICS). The simulation takes into account the main parameters of the laser and electron beams, such as their pulse shapes, polarization properties as well as the angular and energy dispersion of the electrons. The layout of the presented ICS and X-ray optical beamline is dedicated to X-ray micro-diffraction studies. To maintain the axial symmetry of output X-ray beams at different photon energies, the beamline monochromator is based on a single crystal installed in the Borrmann transparency condition. Full article

Yves Klein (1928–1962) is best known for his intensely blue monochromatic works made with International Klein Blue (IKB), a synthetic ultramarine blue pigment bound in a poly(vinyl acetate) binder. However, he also made monochromes in other colors, including red and pink, the pigments of which have never been elucidated. Analysis of one sculpture, three paintings, and one screenprint by micro-Fourier transform infrared spectroscopy (µ-FTIR), Raman and surface-enhanced Raman (SERS) spectroscopies, portable X-ray fluorescence spectroscopy (p-XRF), and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectrometry (EDX), revealed that Klein used, knowingly or unknowingly, a variety of pink and red pigments, including Para Red, rhodamine 6G, rhodamine B, eosin Y, and alizarin lakes. The unexpected variety of pigments contrasts with his use of a single blue pigment and suggests he may not have held a singular vision of what constituted an iconic red or pink color. Full article

Free electron laser (FEL) is capable of producing ultra-short X-ray pulses. The estimation of X-ray pulse propagation is the key process of X-ray FEL beamline design. By using the Kostenbauder matrix approach, the evolution of an ultra-short pulse in a beamline system can be calculated. Therefore, it is of significant importance to investigate the Kostenbauder matrices of different kinds of X-ray optics. In this work, we derive a unified 6 × 6 optical matrix to describe various kinds of X-ray optical elements, including varied-line-spacing (VLS) toroidal grating, VLS spherical grating, VLS cylindrical grating, VLS plane grating, toroidal grating, spherical grating, cylindrical grating, plane grating, toroidal mirror, spherical mirror, cylindrical mirror, and plane mirror. These optics are usually adopted in soft X-ray regime. We apply this method to describe the transverse focusing, pulse front tilt, and pulse stretching after an X-ray pulse going through a VLS plane grating monochromator (VLS-PGM). We also use this approach to simulate a grating compressor which can be used to compress chirped soft X-ray pulse. This work is helpful in the design and optimization of X-ray beamline systems. Full article

Serial crystallography (SX) enables the determination of room-temperature structures with minimal radiation damage. The photon flux of the pink beam of 1.2% bandwidth (BW) is one order higher than that of the monochromatic beam from a silicon crystal monochromator, and the energy resolution of 1.2% BW is enough to solve the structure; therefore, it is useful to use the pink beam for time-resolved serial synchrotron crystallography (SSX). Here, we demonstrate a pink-beam serial synchrotron crystallographic study at the 1C beamline at the Pohang Light Source II. Lysozyme crystals embedded in a beef tallow injection matrix were delivered through a syringe into the X-ray interaction point. Pink-beam SSX was performed with different X-ray exposure positions to the injection stream (center and edge) and X-ray exposure times (50 and 100 ms). All lysozyme crystal structures were successfully determined at a high resolution of 1.7 Å. Background analysis showed that X-ray diffraction data exposed to the edge of the injection stream could improve the signal-to-noise ratio. All the diffraction data and room-temperature lysozyme structures were comprehensively compared. The data collection strategy and analysis will be helpful in further pink-beam SSX experiments and their applications. Full article

Early detection increases overall survival among patients with lung cancer. This study formulated a machine learning method that processes chest X-rays (CXRs) to detect lung cancer early. After we preprocessed our dataset using monochrome and brightness correction, we used different kinds of preprocessing methods to enhance image contrast and then used U-net to perform lung segmentation. We used 559 CXRs with a single lung nodule labeled by experts to train a You Only Look Once version 4 (YOLOv4) deep-learning architecture to detect lung nodules. In a testing dataset of 100 CXRs from patients at Taipei Veterans General Hospital and 154 CXRs from the Japanese Society of Radiological Technology dataset, the sensitivity of the AI model using a combination of different preprocessing methods performed the best at 79%, with 3.04 false positives per image. We then tested the AI by using 383 sets of CXRs obtained in the past 5 years prior to lung cancer diagnoses. The median time from detection to diagnosis for radiologists assisted with AI was 46 (3–523) days, longer than that for radiologists (8 (0–263) days). The AI model can assist radiologists in the early detection of lung nodules. Full article

In several of his artworks, for instance the Venezie cycle, Fontana employed metallic paints; previous investigations on such materials highlighted the use of different synthetic binders and of thick paint layers below the metal one, having different colours to change the visual perception of the metallic surface. In the present work, a monochrome silver “Concetto spaziale” by the Italo–Argentine artist belonging to a private collection recently gifted to the museum of the Church of San Fedele in Milano, Italy, was investigated to deepen the knowledge of this particular group of Fontana’s paintings. The artwork was initially visually inspected in visible and ultraviolet (UV) light. Subsequently, a non-invasive spectroscopic investigation was performed by X-ray fluorescence (XRF), reflection Fourier-transform infrared (FTIR) and Raman spectroscopy. A minute fragment of silver-coloured paint was taken from the reverse of the painting, near the cut edge, and examined by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX) and micro-Fourier-transform Raman (FT-Raman) spectroscopy. The analytical data made it possible to identify the composition of the metallic paint layer and of the underlying dark one, both from the point of view of the pigments and of the binders used, also highlighting the potential of the non-invasive and micro-invasive methods adopted in the investigation. Full article

As a core component of the X-ray absorption fine structure spectroscopy (XAFS) system, the multi-channel double-crystal monochromator (DCM) can improve the time resolution of the system significantly. In contrast to the conventional single-channel DCM, the multi-channel DCM includes more pairs of crystals that are located separately in the master and slave motor axis with the same driving direction. However, a mismatched parallelism in the pitch direction, which can result from the manual mounting operation between the two separated crystals, directly affects the performance of the flux and the angular stability of the monochromatic beam. This poses a significant challenge to the precision position tracking of this system. In this paper, the mounting errors were translated into repetitive errors in the slave motor when the master motor was rotated at a constant velocity. Therefore, the iterative learning control (ILC) was considered in order to improve the tracking accuracy of the slave motor motion. The zero-magnitude error controller (ZMETC) was used to calculate the learning function to accelerate the convergence of the control inputs, and the convergence conditions of the control signal and error were also given. To validate the effectiveness of the proposed method, comparative experiments were performed on the motor motion platform. Experimental results indicated that the ILC effectively decreased the parallelism errors of the multi-channel DCM under various trajectories by comparing them with feedback controllers and the ZMETC, respectively. Full article

A variable resolution, transform limited monochromator is designed for the Free Electron Laser (FEL) source of LCLS. It provides monochromatic beam in the 250–1500 eV range, delivering the beam on the second floor of the LCLS experimental Hall. One major requirement for this monochromator is to provide, as close as possible, monochromatic transform limited pulses for time-resolved experiments. The theory and the limit of using classical diffraction scheme to monochromatize Soft X-ray beam, while preserving the pulse length, will be presented, together with the optical scheme of this versatile monochromator design. Full article