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Milling influences flour morphology and the molecular structure of starch. Such structure-function interactions are crucial in determining ingredient functionality to develop specific end-products. Laboratory scale X-ray instruments offer limited brightness and are time-consuming when investigating the porosity, starch lamellar structure, and crystallinity of pulse flours. Herein, synchrotron X-rays were employed along with mid-infrared spectroscopy (mid-IR) and scanning electron microscopy to non-invasively investigate the molecular changes in roller-milled yellow pea flour as influenced by milling configurations (termed as flour streams) and flour blending (termed as flour blends). Our results illustrate that flour streams have higher overall protein content, distinct flour morphology, starch lamellar structure, and starch and protein quality than flour blends. Interestingly, flour blends (21.79 to 29.27%) displayed an overall higher degree of crystallinity than flour streams (20.03 to 25.75%). The broadband absorption spectra in the 1200–900 cm⁻¹ range showed carbohydrate features, while protein spectra in the 1600–1500 cm⁻¹ range highlighted amide I (~ 1650 cm⁻¹) and amide II (~ 1540 cm⁻¹) bands. Secondary protein structures, analyzed through second derivative spectra (1700–1600 cm⁻¹), revealed consistent β-sheet (~ 1636 cm⁻¹) and α-helix (~ 1656 cm⁻¹) ratios, with absorbance changes reflecting protein content variations in flour streams and blends. Furthermore, a principal component analysis model was developed with a total variance of 95.2%, using mid-IR data to classify the samples based on their streams and blends. In conclusion, the state-of-the-art advanced techniques captured and characterized the micro and macromolecular changes in pulse flours as influenced by milling. Highlights: Distinct porosity observed in flour streams and blends. Flour streams showed higher protein content than blends. Milling caused no changes in molecular or protein structures. Amide peaks differentiated low and high protein flour. [ABSTRACT FROM AUTHOR]

Utilized the upgraded Synchrotron-based non-destructive Diffraction-enhanced imaging and Diffraction-enhanced imaging coupled with CT X-ray imaging systems to image the chickpea seeds, to enhance the contrast in plant root architecture, visibility of fine structures of root architecture growth and some aspects of physiology at acceptable level. DEI-CT images were acquired with 30 keV synchrotron X-rays. A series of DEI-CT slices were assembled together, to form a 3D data set. DEI-CT images explored more structural information and morphology. Noticed detailed anatomical, physiological observations, and contrast mechanisms. With these systems, some of the complex plant traits, root morphology, growth of laterals and subsequent laterals can be visualized directly. [ABSTRACT FROM AUTHOR]

X-ray fluorescence (XRF) is widely used to analyze elemental distributions in samples. Micro-XRF (µ-XRF), the most basic conventional XRF technique, offers good spatial resolution through precise 2D scanning with a micrometre-sized X-ray source. Recently, synchrotron based XRF analysis platforms have achieved nano-XRF with highly focused X-rays using polycapillary optics or mirrors, leveraging the excellent coherence of synchrotron radiation. However, XRF techniques are hindered by long data acquisition times (exceeding several hours) due to their point-by-point scanning approach, impeding large-area elemental mapping. Full-field XRF (FF-XRF), developed in the 2010s and based on the high brilliance of synchrotron X-rays, enables significantly shorter (less than a few minutes) data acquisition times via single-exposure imaging using a 2D X-ray detector. Nevertheless, it is constrained by relatively low spatial resolution and sensitivity. Hence, a new XRF platform is required to accommodate resolution demands to cover diverse experimental purposes. In this study, we developed a preliminary model of a novel XRF system that combines micro- and full-field XRF setups to address these limitations. This system allows easy mode switching while maintaining the region of interest of the imaging system within a single apparatus, simply by rotating the sample to face either detector depending on research purposes. We anticipate that this new XRF system will be widely utilized in various research fields as the initial XRF setup at Pohang Light Source-II.

Improving the scalability of tissue imaging throughput with bright, coherent X-rays requires identifying and mitigating artifacts resulting from the interactions between X-rays and matter. At synchrotron sources, long-term imaging of soft tissues in solution can result in gas bubble formation or cavitation, which dramatically compromises image quality and integrity of the samples. By combining in-line phase-contrast imaging with gas chromatography in real time, we were able to track the onset and evolution of high-energy X-ray-induced gas bubbles in ethanol-embedded soft tissue samples for tens of minutes (two to three times the typical scan times). We demonstrate quantitatively that vacuum degassing of the sample during preparation can significantly delay bubble formation, offering up to a twofold improvement in dose tolerance, depending on the tissue type. However, once nucleated, bubble growth is faster in degassed than undegassed samples, indicating their distinct metastable states at bubble onset. Gas chromatography analysis shows increased solvent vaporization concurrent with bubble formation, yet the quantities of dissolved gasses remain unchanged. By coupling features extracted from the radiographs with computational analysis of bubble characteristics, we uncover dose-controlled kinetics and nucleation site-specific growth. These hallmark signatures provide quantitative constraints on the driving mechanisms of bubble formation and growth. Overall, the observations highlight bubble formation as a critical yet often overlooked hurdle in upscaling X-ray imaging for biological tissues and soft materials and we offer an empirical foundation for their understanding and imaging protocol optimization. More importantly, our approaches establish a top-down scheme to decipher the complex, multiscale radiation–matter interactions in these applications.

The novel hetero‐dinuclear complex trans,trans,trans‐[PtIV(py)2(N3)2(OH)(μ‐OOCCH2CH2CONHCH2‐bpyMe)IrIII(ppy)2]Cl (Pt‐Ir), exhibits charge transfer between the acceptor photochemotherapeutic Pt(IV) (Pt‐OH) and donor photodynamic Ir(III) (Ir‐NH2) fragments. It is stable in the dark, but undergoes photodecomposition more rapidly than the Pt(IV) parent complex (Pt‐OH) to generate Pt(II) species, an azidyl radical and 1O2. The Ir(III)* excited state, formed after irradiation, can oxidise NADH to NAD⋅ radicals and NAD+. Pt‐Ir is highly photocytotoxic towards cancer cells with a high photocytotoxicity index upon irradiation with blue light (465 nm, 4.8 mW/cm2), even with short light‐exposure times (10–60 min). In contrast, the mononuclear Pt‐OH and Ir‐NH2 subunits and their simple mixture are much less potent. Cellular Pt accumulation was higher for Pt‐Ir compared to Pt‐OH. Irradiation of Pt‐Ir in cancer cells damages nuclei and releases chromosomes. Synchrotron‐XRF revealed ca. 4× higher levels of intracellular platinum compared to iridium in Pt‐Ir treated cells under dark conditions. Luminescent Pt‐Ir distributes over the whole cell and generates ROS and 1O2 within 1 h of irradiation. Iridium localises strongly in small compartments, suggestive of complex cleavage and excretion via recycling vesicles (e.g. lysosomes). The combination of PDT and PACT motifs in one molecule, provides Pt‐Ir with a novel strategy for multimodal phototherapy. [ABSTRACT FROM AUTHOR]

Improving the scalability of tissue imaging throughput with bright, coherent X-rays requires identifying and mitigating artifacts resulting from the interactions between X-rays and matter. At synchrotron sources, long-term imaging of soft tissues in solution can result in gas bubble formation or cavitation, which dramatically compromises image quality and integrity of the samples. By combining in-line phase-contrast imaging with gas chromatography in real time, we were able to track the onset and evolution of high-energy X-ray-induced gas bubbles in ethanol-embedded soft tissue samples for tens of minutes (two to three times the typical scan times). We demonstrate quantitatively that vacuum degassing of the sample during preparation can significantly delay bubble formation, offering up to a twofold improvement in dose tolerance, depending on the tissue type. However, once nucleated, bubble growth is faster in degassed than undegassed samples, indicating their distinct metastable states at bubble onset. Gas chromatography analysis shows increased solvent vaporization concurrent with bubble formation, yet the quantities of dissolved gasses remain unchanged. By coupling features extracted from the radiographs with computational analysis of bubble characteristics, we uncover dose-controlled kinetics and nucleation site-specific growth. These hallmark signatures provide quantitative constraints on the driving mechanisms of bubble formation and growth. Overall, the observations highlight bubble formation as a critical yet often overlooked hurdle in upscaling X-ray imaging for biological tissues and soft materials and we offer an empirical foundation for their understanding and imaging protocol optimization. More importantly, our approaches establish a top-down scheme to decipher the complex, multiscale radiation-matter interactions in these applications. [ABSTRACT FROM AUTHOR]

High-resolution imaging with compositional and chemical sensitivity is crucial for a wide range of scientific and engineering disciplines. Although synchrotron X-ray imaging through spectromicroscopy has been tremendously successful and broadly applied, it encounters challenges in achieving enhanced detection sensitivity, satisfactory spatial resolution, and high experimental throughput simultaneously. In this work, based on structured illumination, we develop a single-pixel X-ray imaging approach coupled with a generative image reconstruction model for mapping the compositional heterogeneity with nanoscale resolvability. This method integrates a full-field transmission X-ray microscope with an X-ray fluorescence detector and eliminates the need for nanoscale X-ray focusing and raster scanning. We experimentally demonstrate the effectiveness of our approach by imaging a battery sample composed of mixed cathode materials and successfully retrieving the compositional variations of the imaged cathode particles. Bridging the gap between structural and chemical characterizations using X-rays, this technique opens up vast opportunities in the fields of biology, environmental, and materials science, especially for radiation-sensitive samples. [ABSTRACT FROM AUTHOR]

Background: Electron synchrotrons produce x‐ray beams with dose rates orders of magnitude greater than conventional x‐ray tubes and with beam sizes on the order of a few millimeters. These characteristics put severe challenges on current dosimeters to accurately realize absorbed dose or air kerma. Purpose: This work seeks to investigate the suitability of a novel aluminum‐based calorimeter to determine absorbed dose to water with an uncertainty significantly smaller than currently possible with conventional detectors. A lower uncertainty in the determination of absolute dose rate would impact both therapeutic applications of synchrotron‐produced x‐ray beams and research investigations. Methods: A vacuum‐based calorimeter prototype with an aluminum core was built, matching the beam profile of the 140 keV monochromatic x‐ray beam, produced by the Canadian Light Source Biomedical Imaging and Therapy beamline. The choice of material and overall calorimeter design was optimized using FEM thermal modeling software while Monte Carlo radiation transport simulations were used to model the impact of interactions of the radiation beam with the detector components. Results: Corrections for both the thermal conduction and radiation transport effects were of the order of 3% and the simplicity of the geometry, combined with the monochromatic nature of the incident x‐ray beam, meant that the uncertainty in each correction was ≤0.5%. The calorimeter performance was found to be repeatable over multiple irradiations of 1 Gy at the ± 0.6% level, and no systematic dependence on environmental effects or total dose was observed. Conclusion: The combined standard uncertainty in the determination of absorbed dose to aluminum was estimated to be 0.8%, indicating that absorbed dose to water, the ultimate quantity of interest, could be determined with an uncertainty on the order of 1%. This value is an improvement over current techniques used for synchrotron dosimetry and comparable with the state‐of‐the art for conventional kV x‐ray dosimetry. [ABSTRACT FROM AUTHOR]

Slags fromthe remoteMota Farun locality above Casaccia (Val Bregaglia, Swiss Alps) have been analyzed with scanning electron microscopy, X-ray powder diffraction and microfocus synchrotron X-ray diffraction to determine mineralogical composition and microstructures. Non-magnetic slag samples are largely composed of euhedral and dendritic iron-rich olivine in a glassy matrix. Locally there are zones with globular inclusions rich in bornite ((Cu5Fe)S4) and locally metallic copper. Some regions display dendritic pentlandite ((Fe,Ni)9S8). Magnetic samples are mainly composed of fayalite (Fe2SiO4) and wüstite (FeO), with minor magnetite (Fe3O4). The mineralogical composition indicates that slags were the product of copper smelting. The slag compositions andmorphologies are analogous to slags described from the Oberhalbstein (Graubünden, Switzerland) and the Trentino Alps (Italy) which are attributed to metallurgical exploitations of the Late Bronze Age. While the origin of the ore could not be determined, it may be related to ore deposits of chalcopyrite in greenschists and serpentinites in the vicinity, such as Alp Tgavretga (Septimer Pass) and Val Perossa (Val Bregaglia).

Slags fromthe remoteMota Farun locality above Casaccia (Val Bregaglia, Swiss Alps) have been analyzed with scanning electron microscopy, X-ray powder diffraction and microfocus synchrotron X-ray diffraction to determine mineralogical composition and microstructures. Non-magnetic slag samples are largely composed of euhedral and dendritic iron-rich olivine in a glassy matrix. Locally there are zones with globular inclusions rich in bornite ((Cu5Fe)S4) and locally metallic copper. Some regions display dendritic pentlandite ((Fe,Ni)9S8). Magnetic samples are mainly composed of fayalite (Fe2SiO4) and wüstite (FeO), with minor magnetite (Fe3O4). The mineralogical composition indicates that slags were the product of copper smelting. The slag compositions andmorphologies are analogous to slags described from the Oberhalbstein (Graubünden, Switzerland) and the Trentino Alps (Italy) which are attributed to metallurgical exploitations of the Late Bronze Age. While the origin of the ore could not be determined, it may be related to ore deposits of chalcopyrite in greenschists and serpentinites in the vicinity, such as Alp Tgavretga (Septimer Pass) and Val Perossa (Val Bregaglia).

[Display omitted] • Chickpea blends exhibited lower protein content than navy bean blends. • Blending ratio plays a significant role in determining flour properties. • Chickpea blends depicted higher porosity than navy bean blends. • Seed route influences the blending ratio. Flour blending ratios influence the micro- and molecular properties of flour, which, in turn, determine the essential structure-function relationships crucial for shaping ingredient functionality and creating customized end-products. Conventional laboratory-scale X-ray instruments, constrained by limited brightness and measurement time, present obstacles in investigating porosity, starch lamellar structure, and crystallinity in pulse flours. To address these challenges, this study uses synchrotron X-rays, laser diffraction, mid-infrared spectroscopy, and scanning electron microscopy to non-invasively examine micro and molecular changes in roller-milled chickpea and navy bean flour, accounting for flour blending ratios. The results illustrate a multimodal particle size distribution curve, with each flour blend displaying a distinctive morphology. Chickpea blends showed greater overall porosity than navy bean blends, while navy bean flour blends displayed slightly higher absorbance ratios. The macromolecular changes in flour properties as a result of blending unravel novel information that will be of immense use to food manufacturers. [ABSTRACT FROM AUTHOR]

Using synchrotron X-ray diffraction, tomography and machine-learning enabled phase segmentation strategy, we have studied under operando conditions the nucleation, co-growth and dynamic interplays among the dendritic and multiple intermetallic phases of a typical recycled Al alloy (Al5Cu1.5Fe1Si, wt.%) in solidification with and without ultrasound. The research has revealed and elucidated the underlying mechanisms that drive the formation of the very complex and convoluted Fe-rich phases with rhombic dodecahedron and 3D skeleton networks (the so-called Chinese-script type morphology). Through statistical microstructural analyses and numerical modelling of the ultrasound melt processing, the research has demonstrated that a short period of ultrasound processing of just 7 s in the liquid state is able to reduce the average size of the α-Al dendrites and the Fe-containing intermetallic phases by ∼5 times compared to the cases without ultrasound. For the first time, this work has revealed fully the nucleation and growth dynamics of the convoluted morphology of the Fe-containing intermetallic phases in 4D domain. The research has also demonstrated clearly the beneficial effects of applying ultrasound to control the Fe phases' morphology in recycled Al alloys and it is one of the most effective and green processing strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

The efficacy of an elasto-viscoplastic fast Fourier transform (EVPFFT) code was assessed based on blind predictions of micromechanical fields in a sample of Inconel 625 produced with additive manufacturing (AM) and experimentally characterized with high-energy X-ray diffraction microscopy during an in situ tensile test. The blind predictions were made in the context of Challenge 4 in the AFRL AM Modeling Challenge Series, which required predictions of grain-averaged elastic strain tensors for 28 unique target (Challenge) grains at six target stress states given a 3D microstructural image, initial elastic strains of Challenge grains, and macroscopic stress–strain response. Among all submissions, the EVPFFT-based submission presented in this work achieved the lowest total error in comparison with experimental results and received the award for Top Performer. A post-Challenge investigation by the authors revealed that predictions could be further improved, by over 25% compared to the Challenge-submission model, through several model modifications that required no additional information beyond what was initially provided for the Challenge. These modifications included a material parameter optimization scheme to improve model bias and the incorporation of the initial strain field through both superposition and eigenstrain methods. For the first time with respect to EVPFFT modeling, an ellipsoidal-grain-shape Eshelby approximation was tested and shown to improve predictive capability compared to previously used spherical-grain-shape assumptions. Lessons learned for predicting full-field micromechanical response using the EVPFFT modeling method are discussed. [ABSTRACT FROM AUTHOR]

As a part of a research into new techniques for purifying recycled aluminium alloys, a novel electromagnetic apparatus had been developed for investigating in real-time the separation mechanisms of detrimental inclusions in aluminium alloy melts under alternating magnetic fields. The magnetic coil was designed based on the Helmholtz coil design. A viewing gap was designed for in-situ imaging studies using synchrotron X-rays. The gap was designed to maintain a uniform magnetic field in the central region where a sample is positioned. The current setup for the magnetic coil pair is able to produce a peak magnetic flux density of ~10 mT at a frequency of 25 kHz. A separate electrical resistance furnace, designed to concentrically fit within the magnetic coils, was used to control the heating (up to ~850°C) and cooling of the samples. After a series of systematic tests and commissioning, the apparatus was used in a number of in-situ and ex-situ experiments.

Abstract Background Resistance to radiotherapy is frequently encountered in patients with glioblastoma multiforme. It is caused at least partially by the high glutathione content in the tumour tissue. Therefore, the administration of the glutathione synthesis inhibitor Buthionine-SR-Sulfoximine (BSO) should increase survival time. Methods BSO was tested in combination with an experimental synchrotron-based treatment, microbeam radiation therapy (MRT), characterized by spatially and periodically alternating microscopic dose distribution. One hundred thousand F98 glioma cells were injected into the right cerebral hemisphere of adult male Fischer rats to generate an orthotopic small animal model of a highly malignant brain tumour in a very advanced stage. Therapy was scheduled for day 13 after tumour cell implantation. At this time, 12.5% of the animals had already died from their disease. The surviving 24 tumour-bearing animals were randomly distributed in three experimental groups: subjected to MRT alone (Group A), to MRT plus BSO (Group B) and tumour-bearing untreated controls (Group C). Thus, half of the irradiated animals received an injection of 100 μM BSO into the tumour two hours before radiotherapy. Additional tumour-free animals, mirroring the treatment of the tumour-bearing animals, were included in the experiment. MRT was administered in bi-directional mode with arrays of quasi-parallel beams crossing at the tumour location. The width of the microbeams was ≈28 μm with a center-to-center distance of ≈400 μm, a peak dose of 350 Gy, and a valley dose of 9 Gy in the normal tissue and 18 Gy at the tumour location; thus, the peak to valley dose ratio (PVDR) was 31. Results After tumour-cell implantation, otherwise untreated rats had a mean survival time of 15 days. Twenty days after implantation, 62.5% of the animals receiving MRT alone (group A) and 75% of the rats given MRT + BSO (group B) were still alive. Thirty days after implantation, survival was 12.5% in Group A and 62.5% in Group B. There were no survivors on or beyond day 35 in Group A, but 25% were still alive in Group B. Thus, rats which underwent MRT with adjuvant BSO injection experienced the largest survival gain. Conclusions In this pilot project using an orthotopic small animal model of advanced malignant brain tumour, the injection of the glutathione inhibitor BSO with MRT significantly increased mean survival time.

Decay time spectra of a scintillator can be measured precisely using synchrotron radiation. In such measurements, one should maintain the constraint that a photodetector detects less than one scintillation photon per excitation event. This is required to ensure the random detection of scintillation light. The scintillation decay times of 20 and 0 wt% Bi 2 O 3 nanoparticle-loaded plastic scintillators (Bi-PLSs) were measured recently using a synchrotron X-ray beam. Phosphor of 2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazoleutyl (butyl-PBD) was mixed with 1 mol% of polyvinyltoluene-based Bi-PLSs. The scintillation pulse-height distribution of the samples was investigated using a cooled SiPM for the decay time measurement. The cooled SiPM detector demonstrated a good energy resolution and could distinguish the number of scintillation photons emitted during one X-ray pulse excitation. The experiments were executed using 67.41 keV X-rays at beamline BL-14A of the Photon Factory ring. From the pulse-height measurements, we determined that a smaller aperture covering the scintillator was crucial for decreasing the frequency of multi-photon events per X-ray event. The decay time values of 20 and 0 wt% Bi-PLS with butyl-PBD were finally obtained as 1.33 ± 0.01 ns and 1.42 ± 0.01 ns under an adjusted experimental condition. A statistical discussion is presented for a timing profile that the single- and multi-photon events form in a time spectrum. [ABSTRACT FROM AUTHOR]

Cubic magnesiowustite has been deformed in a diamond anvil cell at room temperature. We present results for (Mg0.4Fe0.6)O, (Mg0.25Fe0.75)O, and (Mg0.1Fe0.9)O up to 37, 16, and 18 GPa, respectively. The diffraction images, obtained with the radial diffraction technique, are analyzed using both single peak intensities and a Rietveld method. For all samples, we observe a [100] fiber texture but the texture strength decreases with increasing iron content. This texture pattern is consistent with {110}-(1-10) slip. The images were also analyzed for stress, elastic strains, and elastic anisotropy. In general, the stress measured in magnesiowustite samples is lower than previously measured on MgO. The elastic anisotropy deduced from the X-ray measurements shows a broad agreement with models based on measurements with other techniques.

• High-speed synchrotron X-rays reveal rich liquid core states of coaxial atomization. • Transition from a liquid column to an upside-down crown as gas flow increases. • Air pockets, dewetting and ligaments found where a continuous phase is expected. • Swirling gas produces liquid core drastic dewetting and back-and-forth motions. • Bi-stability introduces new timescales and massive changes in boundary layers. The liquid core of a canonical two-fluid coaxial atomizer has been characterized using synchrotron X-rays. The high energy photons allow for high-speed imaging of attenuation through the dense liquid-gas jet core, resolving the internal structures that include entrapped air bubbles and the formation of liquid ligaments and bags. When the gas-to-liquid momentum ratio increases, the liquid core transitions from an intact column, where primary break-up happens several liquid diameters downstream, to a hollow crown with a downstream span comparable to the liquid diameter that disintegrates by shedding ligaments from its rim. At high gas momentum ratios (limited by the sonic velocity at the gas nozzle exit), this crown suffers partial dewetting and, when angular momentum is added to the gas, it dewets on a large section of the liquid injection needle circumference. This partial crown exhibits azimuthal motions along the circumference, on timescales much longer than the relevant flow timescales. The crown attachment to the liquid needle presents a bi-stable nature. The dramatic changes of the liquid core morphology, as the gas momentum and swirl ratios vary, have a strong impact on the gas-liquid boundary layers, which control the liquid break-up mechanisms and the resulting spray characteristics, such as droplet size distributions and the droplet volume fraction across the spray. [ABSTRACT FROM AUTHOR]

• Small or superficial target volumes are optimal for MRT. • Peak doses up to 100 Gy can be achieved with acceptable valley dose to OARs. • Treatment volume is a more important factor than depth in determining PVDR. Synchrotron Microbeam Radiation Therapy (MRT) is a pre-clinical modality characterised by spatial dose fractionation on a microscopic scale. Treatment planning studies using clinical datasets have not yet been conducted. Our aim was to investigate MRT dose-distributions in scenarios refractory to conventional treatment and to identify optimal settings for a future Phase I trial. MRT plans were generated for seven scenarios where re-irradiation was performed clinically. A hybrid algorithm, combining Monte Carlo and convolution-based methods, was used for dose-calculation. The valley dose to organs at risk had to respect the single fraction tolerance doses achieved in the corresponding re-irradiation plans. The resultant peak dose and the peak-to-valley dose ratio (PVDR) at the tumour target volume were assessed. Peak doses greater than 80 Gy in a single fraction, and PVDRs greater than 10, could be achieved for plans with small (<35 cm3) or shallow volumes, particularly recurrent glioblastoma, head and neck tumours, and select loco-regionally recurrent breast cancer sites. Treatment volume was a more important factor than treatment depth in determining the PVDR. The mean PVDR correlated strongly with the size of the target volume (r s = −0.70, p = 0.01). The PVDRs achieved in these clinical scenarios are considerably lower than those reported in previous pre-clinical studies. Our findings suggest that head and neck sites will be optimal scenarios for MRT. [ABSTRACT FROM AUTHOR]

The behavior of microcrystalline zirconium carbide (ZrC) and hafnium carbide (HfC) was studied under highly ionizing irradiation conditions at room temperature. The induced structural modifications were characterized via synchrotron-based X-ray diffraction experiments. Unit-cell expansion and buildup of microstrain were determined across a wide fluence range and linked to chemical compositions of the target material. The observed swelling resulting from irradiation with 198 MeV Xe ions in both carbide materials is characterized by two distinct mechanisms that operate within different fluence regimes. Unit-cell expansion initially proceeds by a direct-impact behavior that reaches saturation, followed at higher fluences by a second, linear swelling regime. The overall behavior, particularly the direct-impact regime, is similar for ZrC and HfC, with a more pronounced second defect accumulation process in HfC. Swelling in ZrC shows the same two distinct mechanisms upon irradiation with 198 MeV Xe ions and 946 MeV Au ions, but swelling induced by the lower-energy ions is greater across the entire fluence series. Accounting for the difference in energy deposition density between the two irradiation conditions reveals that the first swelling mechanism (direct-impact behavior) is likely related to the formation of more simple defects. In contrast, the second damaging mechanism at higher fluences (linear increase) cannot be fully explained by the induced energy density, and swelling remains somewhat higher for the low-velocity Xe irradiation. This may suggest that more complex defects and defect clusters are responsible for this swelling regime, with either their size and/or morphology modified at different energy densities. [ABSTRACT FROM AUTHOR]

Mill settings and blending fractions of roller-milled flours directly influence the particle morphology and flour porosity. Benchtop micro-computed tomography (μCT) is limited in analyzing flour's structure-function dynamics because of its conical X-ray beam. Therefore, synchrotron X-rays (SR) with parallel beams, tunable energy, and enhanced brightness were exploited to gain insights into green lentil flour particle count, equivalent diameter, and porosity. Complementary information from scanning electron microscopy revealed changes in average major diameter and distinctive patterns in flour constituents of the streams and blends. SR-μCT data highlighted a negative correlation between equivalent diameter and porosity, with flour streams exhibiting greater variability in equivalent diameter than blends. Histogram deconvolution analysis unveiled grey value variations in phase shift, enabling the detection of changes in pore size. Employing cutting-edge optical microscopy techniques for a comprehensive microstructural characterization of flours will contribute to the improved utilization of nutrient-dense pulse ingredients by the food industry. [Display omitted] • Protein bodies were clustered or bonded to the starch surface. • Flour streams have a wider range and distinct interquartile range values than flour blends. • SR-μCT images measured the starch, protein, starch protein matrices, and cell fragments' sizes. • SEM images showed a distinct pattern of starch-protein matrices in flour streams and blends. [ABSTRACT FROM AUTHOR]

In this paper, we used synchrotron X-ray radiography and tomography to study systematically and in operando conditions the growth dynamics of the primary Al 3 Ni intermetallic phases in an Al-15wt%Ni alloy in the solidification process with magnetic pulses of up to 1.5 T. The real-time observations clearly revealed the growth dynamics of the intermetallics in time scale from millisecond to minutes, including phase growth instability, side branching, fragmentation and orientation alignment under different magnetic pulse fluxes. A multiphysics numerical model was also developed to calculate the alternating and cyclic Lorentz forces and stresses acting on the Al 3 Ni phases and the nearby melt due to the applied pulses. Combining the results of the operando experiments and modelling, for the first time, the differential forces between the growing Al 3 Ni phases and the nearby melt were quantified. The forces can create slip dislocations at the growing crystal front which can further develop into nm and µm crystal steps for initiating phase branching. Furthermore, the magnitudes of the shear stresses are strongly related to the size, morphological and geometric features of the growing Al 3 Ni phases. Dependent on the magnitude of the shear stresses, phase fragmentation could occur in a single pulse period or in multiple pulse periods via fatigue mechanism. This systematic research work elucidate some of the long-time debated hypotheses concerning intermetallic phases growth instability and phase fragmentation in pulse magnetic fields. The research establishes a robust theoretical framework for quantitative understanding of the intermetallic phase growth dynamics in solidification under pulse magnetic fields. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to their abundance and environmentally benign nature, iron and titanium present as the most attractive potential elements for use in rechargeable sodium-ion batteries (SIBs). Accordingly, two structurally different Fe and Ti based compounds, stoichiometric NaFeTiO 4 and sodium deficient Na x Fe x Ti 2-x O 4 (where x = 0.9, and 0.8), are explored as anode materials for SIBs. Their structure and sodium storage capacity are systematically investigated by using combined structural and electrochemical analysis. Rietveld refinement analysis reveals that the sodium deficiency leads to the structural transformation from a single-tunnel structure (NaFeTiO 4 ) to a zigzag-type double-tunnel structure (Na 0.9 Fe 0.9 Ti 1.1 O 4 and Na 0.8 Fe 0.8 Ti 1.2 O 4 ). The series of sodium deficient compounds bears systematic sodium ion vacancies in their structure up to 20%. Sodium deficiency in the Na x Fe x Ti 2-x O 4 logically provides additional space for accommodating the excess sodium ions as such the Na x Fe x Ti 2-x O 4 compounds with higher level of sodium deficiency show higher specific capacities than the stoichiometric NaFeTiO 4 . All the compounds exhibited very good electrochemical cycling stability, with minimal capacity loss during cycling. The present approach is a model example of improvement in the sodium storage capacity of the anode materials by tuning the chemical composition, and could facilitate the performance improvement of known or new electrode materials for SIBs. [ABSTRACT FROM AUTHOR]

Synchrotron radiation facilities have been established and become very familiar in the polymer community not only from academic but also industrial viewpoints. It is not so unusual now to conduct simultaneous measurements of small-angle X-ray scattering ( SAXS) with other techniques such as wide-angle X-ray scattering, stress-strain, light scattering, and so forth. New techniques have also been established and have become more familiar in recent years. In this review, recent developments in polymer applications of synchrotron SAXS are summarized. Instrumental developments and progress in data analyses are reviewed from the following aspects: ultra-small-angle X-ray scattering, anomalous SAXS, X-ray photon correlation spectroscopy, new types of simultaneous measurements, grazing-incidence SAXS, new trends in nanoparticle analyses and industrial applications. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Synchrotron X-rays on the Swiss Norwegian Beamline and BM28 (XMaS) at the ESRF have been used to record the diffraction response of the PMN-PT relaxor piezoelectric 67% Pb(Mg1/3Nb2/3)O3-33% PbTiO3 as a function of externally applied electric field. A DC field in the range 0-18 kV cm−1 was applied along the [001] pseudo-cubic direction using a specially designed sample cell for in situ single-crystal diffraction experiments. The cell allowed data to be collected on a Pilatus 2M area detector in a large volume of reciprocal space using transmission geometry. The data showed good agreement with a twinned single-phase monoclinic structure model. The results from the area detector were compared with previous Bragg peak mapping using variable electric fields and a single detector where the structural model was ambiguous. The coverage of a significantly larger section of reciprocal space facilitated by the area detector allowed precise phase analysis. [ABSTRACT FROM AUTHOR]

There is evidence for iron dysregulation in many forms of disease, including a broad spectrum of neurodegenerative disorders. In order to advance our understanding of the pathophysiological role of iron, it is helpful to be able to determine in detail the distribution of iron as it relates to metabolites, proteins, cells, and tissues, the chemical state and local environment of iron, and its relationship with other metal elements. Synchrotron light sources, providing primarily X-ray beams accompanied by access to longer wavelengths such as infra-red, are an outstanding tool for multi-modal non-destructive analysis of iron in these systems. The micro- and nano-focused X-ray beams that are generated at synchrotron facilities enable measurement of iron and other transition metal elements to be performed with outstanding analytic sensitivity and specificity. Recent developments have increased the scope for methods such as X-ray fluorescence mapping to be used quantitatively rather than semi-quantitatively. Burgeoning interest, coupled with technical advances and beamline development at synchrotron facilities, has led to substantial improvements in resources and methodologies in the field over the past decade. In this paper we will consider how the field has evolved with regard to the study of iron in proteins, cells, and brain tissue, and identify challenges in sample preparation and analysis. Selected examples will be used to illustrate the contribution, and future potential, of synchrotron X-ray analysis for the characterization of iron in model systems exhibiting iron dysregulation, and for human cases of neurodegenerative disorders including Alzheimer’s disease, Parkinson’s disease, Friedreich’s ataxia and Amyotrophic Lateral Sclerosis.

Stereotactic Synchrotron Radiotherapy (SSRT) and Microbeam Radiation Therapy (MRT) are both novel approaches to treat brain tumor and potentially other tumors using synchrotron radiation. Although the techniques differ by their principles, SSRT and MRT share certain common aspects with the possibility of combining their advantages in the future. For MRT, the technique uses highly collimated, quasi-parallel arrays of X-ray microbeams between 50 and 600 keV. Important features of highly brilliant Synchrotron sources are a very small beam divergence and an extremely high dose rate. The minimal beam divergence allows the insertion of so called Multi Slit Collimators (MSC) to produce spatially fractionated beams of typically ∼25–75 micron-wide microplanar beams separated by wider (100–400 microns center-to-center(ctc)) spaces with a very sharp penumbra. Peak entrance doses of several hundreds of Gy are extremely well tolerated by normal tissues and at the same time provide a higher therapeutic index for various tumor models in rodents. The hypothesis of a selective radio-vulnerability of the tumor vasculature versus normal blood vessels by MRT was recently more solidified. SSRT (Synchrotron Stereotactic Radiotherapy) is based on a local drug uptake of high-Z elements in tumors followed by stereotactic irradiation with 80 keV photons to enhance the dose deposition only within the tumor. With SSRT already in its clinical trial stage at the ESRF, most medical physics problems are already solved and the implemented solutions are briefly described, while the medical physics aspects in MRT will be discussed in more detail in this paper. [ABSTRACT FROM AUTHOR]

Objective . The radiation response of alanine is very well characterized in the MV photon energy range where it can be used to determine the dose delivered with an accuracy better than 1%, making it suitable as a secondary standard detector in cancer radiation therapy. This is not the case in the very low energy keV x-ray range where the alanine response is affected by large uncertainties and is strongly dependent on the x-ray beam energy. This motivated the study undertaken here. Approach . Alanine pellets with a nominal thickness of 0.5 mm and diameter of 5 mm were irradiated with monoenergetic x-rays at the Diamond Light Source synchrotron, to quantify their response in the 8-20 keV range relative to 60 Co radiation. The absorbed dose to graphite was measured with a small portable graphite calorimeter, and the DOSRZnrc code in the EGSnrc Monte Carlo package was used to calculate conversion factors between the measured dose to graphite and the absorbed dose to water delivered to the alanine pellets. GafChromic EBT3 films were used to measure the beam profile for modelling in the MC simulations. Main results . The relative responses measured in this energy range were found to range from 0.616 to 0.643, with a combined relative expanded uncertainty of 3.4%-3.5% ( k = 2), where the majority of the uncertainty originated from the uncertainty in the alanine readout, due to the small size of the pellets used. Significance . The measured values were in good agreement with previously published data in the overlapping region of x-ray energies, while this work extended the dataset to lower energies. By measuring the response to monoenergetic x-rays, the response to a more complex broad-spectrum x-ray source can be inferred if the spectrum is known, meaning that this work supports the establishment of alanine as a secondary standard dosimeter for low-energy x-ray sources., (Creative Commons Attribution license.)

Synchrotron X-ray-induced reduction of Au ions in an aqueous solution with or without support materials is reported. To clarify the process of radiationinduced reduction of metal ions in aqueous solutions in the presence of carbon particles as support materials, in situ time-resolved XANES measurements of Au ions were performed under synchrotron X-ray irradiation. XANES spectra were obtained only when hydrophobic carbon particles were added to the precursor solution containing Au ions. Changes in the shape of the XANES spectra indicated a rapid reduction from ionic to metallic Au in the precursor solution owing to synchrotron X-ray irradiation. In addition, the effects of the wettability of the carbon particles on the deposited Au metallic spots were examined. The deposited Au metallic spots were different depending on the relationship of surface charges between metal precursors and support materials. Moreover, a Au film was obtained as a by-product only when hydrophilic carbon particles were added to the precursor solution containing the Au ions. [ABSTRACT FROM AUTHOR]

There is evidence for iron dysregulation in many forms of disease, including a broad spectrum of neurodegenerative disorders. In order to advance our understanding of the pathophysiological role of iron, it is helpful to be able to determine in detail the distribution of iron as it relates to metabolites, proteins, cells, and tissues, the chemical state and local environment of iron, and its relationship with other metal elements. Synchrotron light sources, providing primarily X-ray beams accompanied by access to longer wavelengths such as infra-red, are an outstanding tool for multi-modal non-destructive analysis of iron in these systems. The micro- and nano-focused X-ray beams that are generated at synchrotron facilities enable measurement of iron and other transition metal elements to be performed with outstanding analytic sensitivity and specificity. Recent developments have increased the scope for methods such as X-ray fluorescence mapping to be used quantitatively rather than semi-quantitatively. Burgeoning interest, coupled with technical advances and beamline development at synchrotron facilities, has led to substantial improvements in resources and methodologies in the field over the past decade. In this paper we will consider how the field has evolved with regard to the study of iron in proteins, cells, and brain tissue, and identify challenges in sample preparation and analysis. Selected examples will be used to illustrate the contribution, and future potential, of synchrotron X-ray analysis for the characterization of iron in model systems exhibiting iron dysregulation, and for human cases of neurodegenerative disorders including Alzheimer's disease, Parkinson's disease, Friedreich's ataxia, and amyotrophic lateral sclerosis. [ABSTRACT FROM AUTHOR]

Hybrid halometalates containing lead, tin, bismuth and antimony and organic cations have recently shown a bevy of interesting photophysical properties. Aiming at finding chemically stable and thermally inert species, three halobismutate species of this class, crystallized with proton sponge-derived cations (PRSH), have been isolated as microcrystalline powders by mixing 1,8-bis(dimethylamino)-naphthalene (proton sponge, or PRS) and bismuth oxide in concentrated HX acids (X ​= ​Cl, Br and I). The two isomorphous (PRSH) 3 Bi 2 X 9 (X ​= ​Br, I) species, containing isolated [Bi 2 X 9 ]3- anions, are triclinic at room temperature and convert upon heating into a monoclinic structure through a displacive phase transformation, fully reversible for X ​= ​I and only partially for X ​= ​Br. At variance, (PRSH)BiCl 4 is polymeric, and contains extended zigzagging 1D chains formed by edge-sharing BiCl 6 octahedra. These species were extensively studied by synchrotron and laboratory X-ray powder diffraction measurements, which enabled to detect the evolution toward the two high-temperature β-phases (X ​= ​Br, I), to derive the structure of five different (significantly complex) species and to assess the thermal strain tensors in the different regimes. Additional thermal, spectroscopic and computational analyses completed the characterization of these materials. Three halobismuthates containing the rigid proton sponge cations were prepared and studied by synchrotron X-ray diffraction methods, variable-temperature laboratory powder diffraction and spectroscopic and computational analyses, highlighting the existence of crystalline high-temperature polymorphs. [Display omitted] • New halobismuthates containing the chemically inert proton-sponge cation have been prepared. • Their crystal structures have been determined by synchrotron X-ray powder diffraction data. • Variable temperature diffraction experiments enabled the detection of high-temperature polymorphs. [ABSTRACT FROM AUTHOR]

Various methods for the degradation and detoxification of textile effluents have been developed in recent years and among these, advanced oxidation processes (AOPs) have been proven to be a successful way of degrading organically contaminated water into a useful form. The synchrotron X-ray (3–20 keV) irradiation-assisted AOP has been developed for the degradation of single and mixed colored industrial wastewater solution. Irradiation experiments were conducted on industrial effluents obtained straight from the cloth industries. The efficiency of AOP was measured by characterizing irradiated industrial wastewater solutions with optical, chemical, and biological characterization techniques. The UV-Vis spectroscopy and chemical oxidation demand (COD) results revealed that the wastewater was degraded and the degradation efficiency could be tailored by varying the X-ray dose. The complete decolorization and ∼ 85% removal in COD was obtained at the X-ray dose of 15000 mAs. Chemical species present in pristine and irradiated wastewater were analyzed using FTIR techniques. The FTIR spectra revealed the destruction of the aromatic ring and nitrogen linkage of wastewater under X-ray irradiation. The technique of liquid chromatography-mass spectroscopy (LC-MS) was employed to identify and quantify the unknown compounds present in pristine as well as X-ray irradiated wastewater solutions. Toxicity assays on gram-negative Escherichia coli (DH5α) clearly show detoxification of X-ray irradiated solutions. This study demonstrates a fast and effective approach for completely degrading and detoxifying industrial wastewater, and has a wide range of applications in environmental remediation. • Synchrotron X-ray-assisted degradation of industrial wastewater was investigated. • Efficiency of AOP was assessed based on degradation, COD & toxicity of wastewater. • Synchrotron X-rays reduced 85% COD and 99% coloration of wastewater solutions. • Inhibition growth of E-Coli shows detoxification of wastewater after irradiation. • Synchrotron X-ray irradiation based AOP could be used for pollutant degradation. [ABSTRACT FROM AUTHOR]

Phase-contrast synchrotron X-ray microtomography (pcSyncX) based on the highly coherent X-ray beam has previously been used to visualize the microstructures of biologic specimens, but it has never been used to evaluate embolic debris adherent on a cerebral protection device (CPD). The purpose of this study was to demonstrate the feasibility of pcSyncX for evaluating embolic debris during carotid artery stenting (CAS). Five patients (four males, age range 67-77 years) with severe carotid artery stenosis underwent CAS. The retrieved CPD was exposed to synchrotron radiation and 1000 pcSyncX projection images were obtained by rotating the CPD through 180°. An X-ray shadow of a CPD was converted into a visual image by the scintillator. After microtomographic reconstruction, the three-dimensionally reconstructed images were further segmented into the embolic debris and CPD. The total volume of emboli was calculated by summing the volume at each scanning level. The number of membrane pores covered by emboli as seen from the outer surface was counted and the percentage of covered area was calculated. Embolic debris was clearly demonstrated not only on the inner surface and within pores but also on the outer surface of the CPD. The mean total volume of embolic debris was 0.538 x 10-6 mm³ (range 0.225-0.965 x 10-6 mm³). Most (61.5%) of the debris was located at the apical one-third of the CPD and 20.8% of the pore area was covered by debris. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a silicon avalanche-photodiode (Si-APD) linear array detector to be used for time-resolved measurements in pulsed synchrotron X-ray experiments. The Si-APD linear array consists of 64 pixels 100×200μm2, with a pixel pitch of 150μm and a depletion depth of 10μm. The nanosecond response and high counting rate of the Si-APD are very valuable for time-resolved X-ray diffraction experiments using pulsed synchrotron radiation. A detector system that can resolve successive X-ray pulses within a short interval of 2ns would be very efficient for recording the intensity and position of X-ray diffraction patterns within a nanosecond period. A prototype detector system equipped with an ultrafast application-specific integrated circuit, field-programmable gate arrays and network processor boards was fabricated. It allowed a high count-rate of >107 cps per channel with a synchrotron X-ray beam; however, the time resolution was limited to 10ns. The detector successfully recorded small-angle X-ray scattering by scanning the detector position. [Copyright &y& Elsevier]

The crystal structure, domain structure and the electrical properties of 0.85(Bi0.5Na0.5)TiO3–0.12BaTiO3–0.03SrTiO3 ceramics have been investigated. Rietveld refinement with Fullprof software was used to analyze the X-ray diffraction data and a two-phase coexistence between a monoclinic (Cm) phase and a tetragonal phase (P4mm) best describes the diffraction patterns from 25°C to 100°C. Results from X-ray diffraction and dielectric measurements show that the Curie temperature is between 220°C and 240°C. The domain structure shows the presence of both non-180° domain walls and 180° domain walls similar to that already observed in Pb(Zr x T1−x )O3 ceramics. The hysteresis curves show that the coercive field decreases with increasing temperature up to 100°C. The piezoelectric charge coefficient at 25°C is 167±25pm/V and increased only slightly with temperature up to 100°C. These properties make this piezoelectric ceramic material suitable for ultrasonic transducers, sonars, hydrophones and other applications. [ABSTRACT FROM AUTHOR]

Abstract: Novel X-ray imaging detectors based on photoluminescence of colour centres in lithium fluoride (LiF) have been proposed and tested for extreme ultraviolet, soft and hard X-rays up to 10keV. For the first time we present the optical characterisation of LiF crystals and thin films irradiated at the TOPO–TOMO beamline of synchroton light source Anka (Karlsruhe, Germany) in the energy range 6–40keV for different exposure times. Absorption and photoluminescence spectra were analysed to study the optical response of the LiF-based detectors. High resolved X-ray imaging of commercial test patterns has been obtained on LiF crystals and films by optical readout with a confocal laser scanning fluorescence microscope. [Copyright &y& Elsevier]

Abstract: Background and purpose: To quantify the late dose-related responses of the rat cervical spinal cord to X-ray irradiations by an array of microbeams or by a single millimeter beam. Materials and methods: Necks of anesthetized rats were irradiated transversely by an 11mm wide array of 52 parallel, 35μm wide, vertical X-ray microbeams, separated by 210μm intervals between centers. Comparison was made with rats irradiated with a 1.35mm wide single beam of similar X-rays. Rats were killed when paresis developed, or up to 383days post irradiation (dpi). Results: Microbeam peak/valley doses of ≈357/12.7Gy to 715/25.4Gy to an 11mm long segment of the spinal cord, or single beam doses of ≈146–454Gy to a 1.35mm long segment caused foreleg paresis and histopathologically verified spinal cord damage; rats exposed to peak/valley doses up to 253/9Gy were paresis-free at 383dpi. Conclusions: Whereas microbeam radiation therapy [MRT] for malignant gliomas implanted in rat brains can be safe, palliative or curative, the high tolerance of normal rat spinal cords to similar microbeam exposures justifies testing MRT for autochthonous malignancies in the central nervous system of larger animals with a view to subsequent clinical applications. [Copyright &y& Elsevier]

In reservoirs used for geologic CO2 sequestration, brine films remaining on mineral surfaces can influence flow, diffusion, and reactions. We have investigated how the capillary (disjoining) potential influences the thickness of a KCsI2 brine film on both smooth and rough SiO2 surfaces [root mean square roughness (Rrms), 1.6 and 330 nm, respectively], under confinement with supercritical (sc) CO2. The thicknesses of brine films coating interior surfaces of SiO2windows in a high‐pressure cell were determined through synchrotron X‐ray fluorescence of two tracer ions (I− and Cs+) at 7.8 MPa and 40°C (representative of conditions at about 0.78 km below the land surface), with scCO2as the immiscible confining fluid. The measured area‐averaged film thicknesses on the 330 nm Rrms silica surface ranged from 265 to 249 nm for capillary potentials measured within a narrow range from 0.18 to 3.7 kPa. Over this same range of potentials, film thicknesses measured on the smooth (1.6 nm Rrms) silica surface were about 2 nm, although equilibrium does not appear to have been achieved. The measured average brine film thicknesses were strongly controlled by surface roughness, with very weak variation in response to the fairly narrow range of tested capillary potentials.Key Points: The experimental approach to measuring the brine film with SXRF methodThe measurement of brine film thickness for both smooth and rough surfaceThe comparison between experimental results and DLVO theory for brine film [ABSTRACT FROM AUTHOR]

Abstract: Using penetrating high-energy synchrotron X-ray radiation and thermal neutrons, the residual strains and stresses associated with the high-velocity oxygen-fuel (HVOF) thermal spray coating of WC–Co on two different substrate materials with significantly different coefficients of thermal expansion (CTE) to that of the coating material, have been investigated in a systematic approach. This approach enabled quantification of the residual strain and stress contributions that emanate from the different processing steps associated with the coating process. An eigenstrain approach enabled direct comparison of the contributions of the different processing steps to the plastic strains. It is shown that the dominant contribution originates from the grit-blast surface preparation step. Contributions purely from the coating process are not distinguishable from that of the grit blasting process within the measurement accuracy. For the as-coated samples no obvious contributions ascribable to the differences in the CTEs of the substrates, or impact related effects are observed. [Copyright &y& Elsevier]

The compressive deformation mechanism of a Zr55Al10Ni5Cu30 bulk metallic glass containing 10vol.% ZrC (ZrC-BMG) has been clarified based on the residual stresses in the compressed specimens. The deformation behavior can be classified into four stages through local plastic deformation around ZrC particles until macroscopic fracture when the ZrC particles break. It was suggested that the plasticity and strength of the ZrC-BMG depend on the compressive strength of the ZrC particles and the stress partitioning into both phases. [Copyright &y& Elsevier]

Abstract: Residual-stress evolution in sputtered encapsulated ZnO/Ag/ZnO stack has been studied in-situ by synchrotron x-ray diffraction when heat treated. The ZnO/Ag/ZnO stack encapsulated into Si3N4 layers and deposited on (001) Si substrates was thermally heated from 25°C to 600°C and cooled down to 25°C. X-ray diffraction 2D patterns captured continuously during the heat treatment allowed monitoring the diffraction peak shifts of both Ag (15nm thick) and ZnO (10nm and 50nm thick) sublayers. Due to the mismatch between the coefficients of thermal expansion, the silicon substrate induced compressive thermal stresses in the films during heating. We first observed a linear increase of the compressive stress state in both Ag and ZnO films and then a more complex elastic-stress evolution starts to operate from about 100°C for Ag and about 250°C for ZnO. Thermal contraction upon cooling seems to dominate so that the initial compressive film stresses relax by about 300 and 700MPa after thermal treatment for ZnO and Ag, respectively. The overall behavior is discussed in terms of structural changes induced by the heat treatment. [Copyright &y& Elsevier]

In this paper, in-situ high-energy X-ray diffraction was employed to trace the phase transition via the change in the lattice strains under multiple (stress and magnetic) fields for a polymer-bonded Ni–Co–Mn–In composite. Under uniaxial compressive deformation, the parent phase in the Ni–Co–Mn–In alloy endured a compressive internal stress along the loading direction and a tensile internal stress in the transverse direction, leading to the formation of a highly textured martensite. This paper is intended to examine the effect of the external magnetic field on the phase transition in two types of martensite, i.e. highly textured martensite and temperature-induced self-accommodated martensite. For the highly textured martensite, a compressive or tensile internal stress can be observed for the parent phase parallel or perpendicular respectively to the preloading direction under an applied magnetic field. This is due to the magnetic-field-induced transformation from the highly textured martensite to the parent phase. For the self-accommodated martensite accompanied by the random distribution of martensitic variants, no obvious internal stresses are generated in the parent phase under an applied magnetic field of up to 6 T. The insight into the stress state of the alloy phase reinforces the in-depth understanding of the role of external fields in affecting the functional performance of the polymer-bonded Ni–Co–Mn–In composite. [ABSTRACT FROM PUBLISHER]