The vacuum ultraviolet (VUV) photochemistry of trifluoromethanesulfonyl fluoride (CF3SO2F), a promising eco-friendly insulating gas to replace sulfur hexafluoride (SF6), was investigated in the 11-14 eV energy range by using synchrotron radiation photoionization mass spectrometry and high-level theoretical calculations. It was found that the CF3SO2F+ parent ion formed from VUV photoionization is not stable and dissociates into CF3+, SO2+, and SOF+ fragment ions. The vertical ionization energy (VIE) of the parent molecule to the repulsive X2A' cationic state was calculated to be 13.46 eV, while the adiabatic ionization energy (AIE) to the bound A2A″ state was determined to be 12.65 eV. Notably, the experimental appearance energies of the CF3+ and SO2+ fragments coincide with the AIE of the first excited state (A2A″), rather than the lower appearance energies predicted from ground-state potential energy surfaces. In addition, the dissociation mechanisms to produce CF3+ and SO2+ fragment ions were discussed in detail. For CF3+, photoexcitation populates the bound A2A″ state, which then crosses via a conical intersection to the repulsive X2A' state, leading to direct dissociation into CF3+ + FSO2. This predissociation pathway governs the experimental onset of the m/z = 69 signal. The m/z = 64 signal, corresponding to the SO2+ fragment, is less intense than the m/z = 69 signal because its formation involves a more complex, multistep pathway. This pathway needs isomerization and crossing another conical intersection, making it less favorable than the direct fragmentation that produces the CF3+ fragment.

Understanding solvent/solute-borne coordination structures and their impact on electrode intercalation chemistry is crucial for the rational design of high-performance electrolytes. Nevertheless, the anion coordination mechanisms governing solvation structures and their influence on electrochemical properties within aqueous zinc-ion electrolytes remain insufficiently explored. In this work, we systematically elucidate the Zn2+ coordination environments in dilute aqueous zinc-ion electrolytes containing three different Zn salts (Zn(OTf)2, ZnCl2, and Zn(Ac)2) using X-ray absorption fine structure (XAFS) spectroscopy and metadynamics simulations. Our results identify distinct average Zn2+ coordination species: [Zn(H2O)6]2+ in Zn(OTf)2, [Zn(H2O)5Cl]+ in ZnCl2, and [Zn(H2O)4(Ac)]+ in Zn(Ac)2. Further employing synchrotron-based spectroscopy and in situ synchrotron radiation X-ray diffraction (SRXRD), we reveal that the electrode operating in Zn(OTf)2 electrolyte exhibits minimal crystal lattice distortion upon Zn2+ de/intercalation cycling, thereby delivering highly reversible electronic structure evolution and zinc-ion electrochemistry. In stark contrast, pronounced structural shape-shifting is observed in ZnCl2 and Zn(Ac)2 electrolytes, attributed to electrode dissolution and acetate anion coinsertion, respectively. These processes induce significant structural deterioration during cycling and compromise electrochemical reversibility. This study provides critical insights into the anion coordination chemistry within aqueous electrolytes and its profound influence on electrode intercalation behaviors, offering essential guidance for developing advanced high-performance aqueous batteries.

Ti-MXene (Ti3C2Tz) is the most common member of a larger family of 2D materials widely explored due to a variety of possible applications. MXenes are mostly synthesized using strong acids like HF and HCl or using procedures that require elevated temperatures. Here, we present a new method for Ti3C2Tz preparation with a weak acid solution, which is more beneficial for mass production with reduced environmental impact. It is demonstrated that aluminum can be etched from titanium aluminum carbide (Ti3AlC2) using ammonium fluoride (NH4F) dissolved in an aqueous solution of acetic acid (CH3COOH). Optimization of the balance between amounts of water and acetic acid in the etching solution allows for complete etching of Al atoms yielding partially nitrogen terminated MXene in addition to common -O/-OH and -F termination. The mechanism of MXene formation was investigated by the in situ synchrotron radiation X-ray diffraction (XRD), allowing characterization of "pristine" MXene structure forming directly in the process of Ti3AlC2 reaction with NH4F/CH3COOH. In situ XRD analysis also enables identification of the reaction byproducts, thus providing information about the mechanism of MXene formation.

ABSTRACT To fully unlock catalytic potential in the oxygen evolution reaction (OER), it is essential to guide the reconstruction process, orienting the evolution from the initial amorphous state into a more potent amorphous structure. We develop an amorphous cobalt coordination polymer (aCo) pre‐catalyst via monodentate end‐capping. In‐situ synchrotron radiation X‐ray diffraction reveals that CH 3 CN coordination disrupts the long‐range topological order while preserving local motifs. The obtained metastable amorphous structure redirect spontaneous surface reconstruction into an amorphous cobalt oxyhydroxide (a‐CoOOH) active layer due to strong d–π* interactions with the lower energetic barrier (−8.175 eV) compared to the crystalline phase on its counterpart (−7.441 eV). The unique amorphous‐to‐amorphous transformation effectively activates lattice oxygen within the metastable framework, switching the OER pathways from the adsorbate evolution mechanism to a lattice oxygen‐mediated mechanism and consequently enhancing OER efficiency and stability. The optimized amorphous aCo can achieve an overpotential of 186 mV at 10 mA cm −2 , much lower than those of RuO 2 (233 mV) and crystalline cCo (308 mV), and it demonstrates stability of over 100 h at 2 A cm −2 . This strategy offers a directed surface‐induced approach for designing next‐generation OER electrocatalysts, providing fundamental insights into the correlation between lattice oxygen activity and structural long‐range disorder.

Additive manufacturing (AM) of Ti-6Al-4V alloy is widely used in aerospace and medical fields due to its excellent strength and corrosion resistance. However, the microstructural heterogeneity induced by the AM process often results in fatigue properties inferior to those of their forged counterparts. Synchrotron Radiation Computed Tomography (SR-CT) was employed to conduct an in situ three-dimensional investigation of fatigue damage evolution in Ti-6Al-4V alloy fabricated via laser powder bed fusion (LPBF). Experimental results revealed phenomena of crack bridging and deflection, accompanied by the consistent presence of local high-density zones (LHDZs) throughout the fatigue damage progression. Combined with quantitative analysis of crack propagation rates, the influence of LHDZs on fatigue damage evolution was analyzed, and the relationship between AM processes, LHDZs, and fatigue damage was discussed. The results indicate that the basket-weave α-phase microstructure in Ti-6Al-4V prepared by LPBF exhibits a high correlation with the distribution of LHDZs, and the orientation of LHDZs aligns with the crack propagation direction. By adjusting process parameters such as cooling rate and temperature gradient, the formation of LHDZs can be modified, thereby influencing the fatigue properties of the material. This provides theoretical support for achieving process optimization of the fatigue properties of Ti-6Al-4V alloy prepared via LPBF.

Propylene oxide is the first chiral molecule identified in the interstellar medium, which has resulted in growing interest in it as a prototypical molecule to study the origin of life on Earth. Numerous spectroscopic studies have investigated the excitation, ionization and dissociation of propylene oxide by photons, electrons and/or ions. However, for vacuum ultraviolet (VUV) photoabsorption spectroscopy, data are available only for energies between 6 and 9 eV with low energy resolution. Here, we present the high-resolution VUV photoabsorption cross-sections in the 6.0-10.8 eV range through an experimental and theoretical approach. The measurements were carried out using a VUV synchrotron radiation light source and are supported by quantum chemical calculations performed using time-dependent density functional theory. There is good agreement between experiment and theory, allowing us to characterize the main absorption bands assigned to electronic transitions involving mainly oxygen lone pairs and lower-lying Rydberg states. At higher energy, there are several Rydberg states observable, characterized by superimposed features with different vibrational progressions. Some features observed in the spectrum are assigned to vibrational modes involving the methyl group, namely CH3 bending (υ22 and υ23) and CH3 torsion (υ24). Additionally, we report a vibrational progression which may be related to the cation ring CC stretching with an average frequency of about 565 cm-1. Calculated potential energy curves for the low-lying excited states along the C-CH3 stretching coordinate reveal that the initial Rydberg states evolve into dissociative states at larger bond distances, as the σ* valence character increases.

Abstract We present a multiwavelength study of blazar PKS 0446+11, motivated by its spatial association with the neutrino event IC 240105A detected by the IceCube Neutrino Observatory on 2024 January 5. The source is located 0 . ° 4 from the best-fit neutrino direction and satisfies selection criteria for very long baseline interferometry–selected, radio-bright active galactic nuclei that have been identified as highly probable neutrino associations. PKS 0446+11 exhibited a major γ -ray flare in 2023 November, reaching ∼18​​​​​​× its 4FGL-DR4 catalog average. Around the neutrino epoch, PKS 0446+11 remained in an elevated state, with the γ -ray flux more than 6 times above its catalog level, the X-ray flux an order of magnitude above the archival measurements, and the optical-UV emission also enhanced. We used Fermi-LAT, Swift-XRT/UVOT, and archival multiwavelength data to construct multiwavelength light curves and spectral energy distributions (SEDs). SED modeling shows that the emission is best described by a leptonic scenario, with synchrotron emission at low energies and external Compton scattering of broad-line region and dusty torus photons dominating the X-ray– γ -ray output. A lepto-hadronic model fails to adequately reproduce the observed SED, although hadronic cascades can broadly account for the X-ray and γ -ray spectral coverage at lower flux levels. We compute the expected neutrino flux for the hadronic scenario and compare it to the IceCube 90% upper limit. Our results highlight the importance of continued multiwavelength and neutrino monitoring to better understand the physical conditions under which this blazar may serve as a neutrino source.

Synchrotron radiation technology, as an indispensable tool in the field of fiber characterization for microstructure analysis, can obtain in-situ and non-destructive microstructure information through high-resolution imaging and three-dimensional structure analysis. However, it still faces many challenges. This paper presents a review of the application of synchrotron radiation technology in fibers and systematically introduces its classification. Based on the energy spectrum, synchrotron radiation X-rays are categorized into soft X-rays, medium-energy X-rays and hard X-rays, and elaborates on their characteristics, techniques and applications in fiber research. Furthermore, synchrotron radiation characterization techniques are classified into X-ray scattering techniques, X-ray absorption fine structure spectroscopy techniques and imaging techniques. This paper summarizes the technical characteristics, scope of application, and advantages of synchrotron radiation in unveiling the structural properties and evolution mechanisms of fiber materials, and offers a perspective on the developmental trends and potential of synchrotron radiation, providing insights for future research and technological advancements.

The present work reports a novel borate layered CeMgB3O7 crystal with an orthorhombic lattice (Cmme) as determined by single-crystal X-ray diffraction, which was synthesized through high-pressure solid-state metathesis reaction, marking the first successful preparation of that type of structure under high pressure and high temperature. Using multimodal characterization techniques, including in situ high-pressure synchrotron radiation X-ray diffraction and Raman spectroscopy, the exceptional structural stability of CeMgB3O7 was confirmed up to 34 GPa. X-ray photoelectron spectroscopy measurements and the photoluminescence (PL) spectroscopy further identified a novel pathway for achieving near-infrared emission in Ce-based materials, highlighting the potential of defect engineering to directly activate luminescent centers within the host lattice in CeMgB3O7. The high-pressure PL spectroscopy indicates that applied pressure effectively modulates the crystal field splitting degree in [CeO10]17-, imposing a direct and tunable influence on its intrinsic luminescence. These findings advance the understanding of luminescence mechanisms in Ce-based systems and offer new insights for the future design of luminescent materials.

Dual-energy CT (DECT) is an important X-ray imaging characterization method that enables 3D imaging of element distribution from micrometer to nanometer scale. However, acquiring DECT data in a single scan with synchrotron radiation is challenging. This study exploits the coexistence of fundamental wave and higher harmonics in the diffracted beam of a double-crystal monochromator. In addition, variations in diffraction bandwidths across different lattice planes are considered. By controlling the detuning angle of the Laue crystal after monochromatization, two spatially separated beams with energy disparity are generated. A sample was placed in the resulting overlapping light field, resulting in spatial differentiation and 3D reconstruction of two different elements. The measured diameters of nickel and silver wires closely match their actual values. Compared to the 3D result at 12 keV, the 36 keV demonstrates significant improvements in reducing metal artifacts. This method provides a solution for elemental resolution and simultaneous sampling, and extends the applications of synchrotron radiation in materials and biomedicine.

Energy dependence of line-resolved M-shell X-ray production cross-sections for hafnium using synchrotron radiation

We report the commissioning of a multimodal computed tomography experimental setup at the 28-ID-2 (XPD) beamline of the National Synchrotron Light Source II. This high-energy (>60 keV) resource features a tunable X-ray beam size ranging from several millimetres to a few micrometres and enables comprehensive characterization of high-Z materials-an essential capability fornuclear and advanced materials research. It provides four complementary computed tomography modalities: X-ray absorption, X-ray fluorescence, X-ray diffraction, and pair distribution function tomography. A case study using a custom-made heterogeneous sample demonstrates these abilities to simultaneously capture atomic, elemental, and morphological information. This unique combination of imaging, structural, and chemical sensitive methods provides a holistic approach to study complex materials with amorphous and crystalline systems across multiple length scales.

Scanning fluorescence X-ray microscopy lets one non-destructively and quantitatively map the distribution of most biologically important metals in cells and tissues. For studies on large-scale tissues and organs, a spatial resolution of several micrometres is often sufficient; in this case, bending magnets at synchrotron light sources provide abundant X-ray flux. We describe here the use of bending magnet beamline 8-BM-B at the Advanced Photon Source with two distinct microscopy stations: a pre-existing one with Kirkpatrick-Baez (KB) mirror optics for slightly higher throughput and the ability to accommodate samples tens of centimetres across, and a new prototype station with an axially symmetric, single-bounce, capillary optic with slightly less flux, but finer resolution at similar fluence per time. The KB station provides δres = 10.5 µm spatial resolution at a per-pixel exposure time of tdwell = 100 ms and a fluence per time of 5.8 × 107 photons µm-2 s-1, while the prototype capillary station provides δres = 6.5 µm at tdwell = 50 ms and a fluence per time of 5.6 × 107 photons µm-2 s-1. We used image power spectral density to estimate the achieved spatial resolution δres from individually acquired images, with δres depending on the optic, the fluorescence signal strength of the sample being imaged, and the method used to process raw fluorescence spectral data.

Study on the stability of NdFeB in IVU for synchrotron radiation and free-electron lasers

Radiation-thermal coupling-driven dynamic restructuring of PAN microfibril: dose-response mechanism of γ-irradiation pre-oxidation revealed by synchrotron radiation USAXS

Decoding ancient mortars: complementary strengths of SR-μXRPD and FPA-FTIR in high-resolution binder analysis.

As the nature of spread through air spaces (STAS) in non-small cell lung cancers (NSCLC) remains a matter of debate, this paper presented the first application of 3D X-ray virtual histology to shed light on the origin of these elements. Five adenocarcinomas and two squamous cell carcinomas were selected from a cohort of NSCLC cases to serve as representative examples of neoplasms in which the presence of STAS had already been assessed through conventional histology. Although available only for research purposes, synchrotron radiation X-ray phase-contrast micro-tomography (μCT) allows virtual sectioning of whole paraffin blocks with spatial and contrast resolution similar to that of histology, thus enabling examination of STAS patterns (e.g., single and clustered tumour cells, micropapillary, solid nests). The 3D results demonstrated that free-floating STAS (i.e., micropapillary and solid patterns) were observed to be only the edges of tumour cell clusters connected to the primary tumour. In contrast, STAS located near alveolar walls or vascular structures suggested tumour cell migration along these surfaces away from the primary tumour. These findings indicate that most STAS types are clusters of cells connected to the main tumour mass. 3D X-ray virtual histological investigation helps to understand the morphological composition and spatial evolution of the tumour, as well as the presence of a tumour larger than that visible in the histological slide. From a radiological and surgical perspective, these findings may influence the assessment of the extent of parenchymal involvement and help guide the surgical approach.

Abstract The multifractal characteristics of coal nanopore structure have important implications for the occurrence and migration of coalbed methane. Based on the in-situ adsorption device, this paper introduced the multifractal theory into the in-situ small angle X-ray scattering (SAXS) method, and synchrotron radiation SAXS was used to study the evolution of nanopore structures and their multifractal characteristics during CO 2 adsorption in cyclically water-immersed coal. The results show that in the above process, both the mesopores and macropores have multifractal characteristics, and the multifractal characteristics of the macropores are more obvious; the pore size distributions of mesopores and macropores are mainly dominated by the dense area, and this dominance is more significant in the macropores. Cyclic water immersion significantly reduces the effect of CO 2 adsorption on 3~20 nm pores in lean coal and long-flame coal, but enhances the effect of CO 2 adsorption on 3~20 nm pores in anthracite. As the number of water immersions increases, the heterogeneity of pore distribution within the 3~83 nm range during CO 2 adsorption by anthracite decreases, and the complexity of its pore structure also decreases. Among them, the heterogeneity of pore size distribution in smaller-sized pores decreases, and the pore size distribution in larger-sized pores is always more uniform. The error ranges between the model and experimental values for the average pore diameter, porosity, and specific surface area of anthracite are basically within −0.576 nm to 0.756 nm, −0.137% to 0.101%, and −4.746 to 3.270 m 2 /cm 3 .

We used synchrotron X-ray diffraction (XRD) and ac-impedance spectroscopy (AIS) to uncover the structural and chemical modifications undergone by RbH2PO4 (RDP) at intermediate temperatures (150 °C < T < 300 °C) and investigate their relationship with RDP’s proton conductivity, σ. Nyquist plots collected on RDP samples sealed in a small volume (~50 mL) of dry air show a gradual increase in σ upon heating from 180 to 260 °C, but not the three-order-of-magnitude superprotonic jump observed in the Cs-based compound CsH2PO4 (CDP) within the same temperature range. Correspondingly, XRD measurements using synchrotron radiation (λ = 0.922 Å) on RDP crystalline powders sealed in a quartz capillary exhibit no evidence of a monoclinic-to-cubic superprotonic phase transition like the one observed in CDP. Instead, these temperature-resolved powder XRD patterns demonstrate that the intermediate-temperature RDP monoclinic phase (P21/m, a = 7.733 Å, b = 6.189 Å, c = 4.793 Å, and β = 109.21 deg) persists up to the melting point of the title compound. Our most significant finding comes from heating RDP under high pressure (P = 1 GPa), which leads to markedly different structural behavior. Indeed, our full profile refinements against XRD data collected on RDP crystals compressed at ~1 GPa show evidence of a polymorphic phase transition (at Tc = 300 °C) to a high-temperature cubic phase (Pm-3m, a = 4.784 Å) that is isomorphic with its CDP counterpart. This is significant, as it indicates that the superprotonic conduction in phosphate solid acids is not cation-specific, and a general highly efficient proton conduction mechanism is present in the high-temperature phases of these materials.

Fixed-target platforms provide convenient support for microcrystals during serial X-ray crystallography studies using synchrotron radiation. Here, we describe a simple user-friendly 3D-printed support where the crystals are sandwiched between two layers of thin X-ray-transparent membrane resulting in very low scattering background. The platform is compatible with magnetic mounting onto the standard goniometer of macromolecular crystallography beamlines. Our design utilizes a 96-well frame that facilitates hanging-drop experiments directly on the membrane using conventional crystallization plates, thereby eliminating multiple pipetting and crystal handling steps. Crystals can be enclosed in a sandwich and packed into `cassettes', preventing the risk of the sample drying out during room-temperature transportation to synchrotron sources. The versatility of the platform is demonstrated by five structures solved using different crystallization and data-collection strategies. Lysozyme single-crystal rotational crystallography at room temperature is shown, as well as microcrystal serial data collection under cryogenic conditions. On-chip microcrystallization is illustrated by use of a photosynthetic reaction center as an example. Finally, serial crystallography data collection at room temperature from microcrystals of the membrane protein cytochrome c oxidase crystallized in lipidic cubic phase is presented.