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Cloud-to-ground lightning can cause high-temperature and high-pressure deformation features in rock at the strike point, forming fulgurite. Although cloud-to-ground lightning is a frequent phenomenon, rock fulgurites are rarely reported. Here, we present field, optical microscope, X-ray fluorescence, scanning and transmission electron microscope, in situ synchrotron projection X-ray microscopy and X-ray diffraction, and Raman data to investigate the formation and preservation of a recently formed rock fulgurite from Kinmen Island, Taiwan. In the field, the fulgurite is asymmetrically distributed on the surface over an ~ 12 m area. In detail, the fulgurite contains an opaque glassy layer comprised of quartz and feldspar clasts, voids, iron-rich spheres, and barite aggregates that overlies fractured quartz grains and feldspar grains with planar features. Secondary minerals found locally adhering to the glassy layer as greenish patches are mainly jarosite group minerals, which commonly form as a secondary hydrothermal alteration product. We interpret the jarosite to have formed during the solidification of melt in the presence of raindrops, suggesting the rapid alteration of glass and short preservation potential of rock fulgurite. Finally, we estimate the production ratio of fulgurite by calculating the energy required for fulgurite formation and that released to the ground by the lightning event. A calculated energy ratio of 0.026% is within the range of 10 to 10 of the lightning total energy delivered to the strike point. We suggest that the scarcity of rock fulgurite in the geological record may be due to both the low production possibility and rapid alteration., The research was supported by the Taiwan ROC (Republic of China) Ministry of Science and Technology (MOST 110–2116-M-008–002-MY2) and Earthquake-Disaster & Risk Evaluation and Management Center (E-DREaM) from the Ministry of Education (MOE) to Li-Wei Kuo. Dennis Brown acknowledges funding (PGC2018-094227-B-I00) from the Spanish Ministry of Science, Innovation, and Universities, as well as a Chaired Professor stipend from the Department of Earth Sciences at National Central University. Jialiang Si acknowledges funding from the National Natural Science Foundation of China (41872211).

Bulk Sb anodes have been reported to exhibit cycle stability in sodium-ion batteries (SIBs) that is considerably superior to that in lithium-ion batteries (LIBs) and that of numerous other alloying metal anodes in both batteries. Herein, the microstructural evolution of micron-sized (>5 μm) Sb particles during (de)sodiation and (de)lithiation cycles was studied using in operando transmission X-ray microscopy. In SIBs, the Sb anode particles exhibit isotropic microstructural and dimensional variations without the formation of a new phase domain or boundary within the interior during the redox cycle, which eventually produces nearly perfect microstructural and dimensional reversibility. The anode exhibits an unprecedented size threshold among alloying metal anodes of approximately 20 μm for nonfracturing. By contrast, the Sb anode particles in LIBs suffer from extensive fractures and porosity formations. The remarkable microstructural reversibility of Sb in SIB can be attributed to its amorphous intermediate reaction pathway, which contrasts with the crystalline-intermediate pathway for the LIB. This study provides direct “visual” evidence to demonstrate the strong causal relationship between the reaction pathway, microstructural transformation, and cycle performance in metal alloying anodes.

A typical Longmaxi (LMX) shale sample from Sichuan basin, China, is investigated in three dimensional through multiscale tomography methods spanning pixel sizes from 3.25 μm to 10 nm, combining X-ray computed tomography and focused ion beam-scanning electron microscopy imaging techniques. Pores, organic matter (OM) and pyrite were segmented and reconstructed at multiple scales and the representative elementary volume (REV) of each phase at different scales based on the convergence of error bars in the volume fraction are determined. Results show that REVs at each scale varied between different phases. The determination of REV defined the applicable scale of different methods as well as the appropriate scales of specific structures. Porosity of LMX shale determined at different scales shows significant difference at two orders of magnitude. This difference likely was caused by structural heterogeneity together with the limitations of methods. This study confirms that REV is a feasible and powerful approach in modeling shale using multiscale 3D imaging. The application of multiscale 3D imaging techniques to worldwide shale gas reservoirs could allow for significant insights into the assessment of migration mechanisms within low-permeability systems.

Projection X-ray microscopy (PXM) and transmission X-ray microscopy (TXM) have been established at beamline 31 at the Taiwan Photon Source (TPS). The TPS 31A beamline is sourced by a wiggler with multiple beam modes: white beam, high-flux mono-beam, and high-resolution mono-beam modes. The PXM is based on a collimated beam, and the TXM is full-field microscopy based on a zoneplate. The PXM system and TXM share the same detector platform, which is equipped with different kinds of detector systems for PXM and TXM. The PXM was designed for high-speed 3D tomography with an automatic tray system for loading and unloading samples, including a robotic arm and pre-alignment system. Both the PXM and TXM systems were designed for use in situ, which requires longer working distance for the sample’s environmental cell.

Nanoscale lead (Pb) dioxide particles (nPbO2) are a newly identified corrosion product formed inside lead-bearing pipes or lead-containing faucets in drinking water distribution systems. These particles can release toxic lead ions, which cause drinking-water contamination and lead poisoning in humans, especially children. nPbO2 may be dislodged from pipes into drinking water; however, little research has focused on the bioavailability and toxicity of nPbO2in vivo. In this study, we used adult medaka fish (Oryzias latipes) as an animal model to investigate the uptake, lead dissolution, bioaccumulation and toxic effects of nanoscale [nPbO2] and microscale bulk [bPbO2] Pb dioxide and Pb(II)aq (Pb2+) in vivo upon acute to sub-chronic aqueous exposure. Both types of PbO2 particles were chemically stable in dechlorinated tap water with low water solubility. However, the X-ray absorption near-edge structure (XANES) analysis and analytical quantification of lead speciation showed that both nPbO2 and bPbO2 could be reductively dissolved into Pb(II)aq in both the intestine (major uptake route) and gills of the fish; thereby, enhancing hepatic Pb accumulation. The fish brains exhibited greater Pb accumulation and acetylcholinesterase inhibition with Pb(II)aq treatment than all the PbO2 treatments. The Pb content was greater in the gills, liver and brain with nPbO2 than bPbO2. This in vivo evidence implies the possibility of increased risk of exposure to Pb dissolution from PbO2 particles in the digestive system via drinking water, which can enhance the bioavailability of Pb uptake and toxicity in humans.

Polarity reversals of the geomagnetic field have occurred through billions of years of Earth history and were first revealed in the early 20th century. Almost a century later, details of transitional field behavior during geomagnetic reversals and excursions remain poorly known. Here, we present a multidecadally resolved geomagnetic excursion record from a radioisotopically dated Chinese stalagmite at 107-91 thousand years before present with age precision of several decades. The duration of geomagnetic directional oscillations ranged from several centuries at 106-103 thousand years before present to millennia at 98-92 thousand years before present, with one abrupt reversal transition occurring in one to two centuries when the field was weakest. These features indicate prolonged geodynamo instability. Repeated asymmetrical interhemispheric polarity drifts associated with weak dipole fields likely originated in Earth's deep interior. If such rapid polarity changes occurred in future, they could severely affect satellites and human society.

Transmission X-ray microscopy has caught lots of attention in recent years because it can give us information on the physical characteristics of absorption contrast and phase contrast of the variou...

Designing metal/C nanocomposites has been a prevalent strategy to address the volume expansion issue of alloying metal Na-ion battery (NIB) anodes but typically suffers from poor volumetric capacity. Here, micrometer-sized nanoporous Sb/C anode with high volumetric capacity and outstanding electrochemical performance is successfully synthesized using facile synthesis of a new class of solid-state reduction chemistry. The resulting Sb/C composite, containing 10 wt % C, possesses the combination of unique structural characteristics, including (1) micrometer-sized secondary particle, enabling high particle density; (2) nanoscale Sb crystallites, permitting reversible phase transformation during cycling; and (3) uniformly distributed nanoporosity, providing accommodation for Sb expansion and facile Na-ion diffusion. The Sb/C composite anode, showing outstanding cycling stability, exhibits a gravimetric capacity of 436 mAh g–1-(Sb+C), a volumetric capacity of 427 mAh cm–3 and over 80% capacity retention at nea...

Li-rich metal oxides, regarded as a high-voltage composite cathode, is currently one of the hottest positive electrode material for lithium-ion batteries, due to its high-capacity and high-energy performance. The crystallography, phase composition and morphology can be altered by synthesis parameters, which can influence drastically the capacity and cycling performance. In this work, we demonstrate Li 1.207 Ni 0.127 Mn 0.54 Co 0.127 O 2 , obtained by a co-precipitation method, exhibits super-high specific capacity up to 298 mAh g −1 and excellent capacity retention of ∼100% up to 50 cycles. Using neutron powder diffraction and transmission X-ray microscopy, we have found that the cooling-treatments applied after sintering during synthesis are crucially important in controlling the phase composition and morphology of the cathodes, thereby influencing the electrochemical performance. Unique spherical microstructure, larger lattice, and higher content of Li-rich monoclinic component can be achieved in the rapid quenching process, whereas severe particle cracking along with the smaller lattice and lower monoclinic component content is obtained when natural cooling of the furnace is applied. Combined with electrochemical impedance spectra, a plausible mechanism is described for the poorer specific capacity and cycling stability of the composite cathodes.

Lithium dendrite growth dynamics on Cu surface is first visualized through a versatile and facile experimental cell by in operando transmission X-ray microscopy (TXM). Galvanostatic plating and stripping cycle(s) are applied on each cell. Upon plating/stripping at ∼1 mA cm–2, mossy lithium is clearly found growing and shrinking on the Cu surface as the application time increases. It is interesting to note that the aspect ratio (height/width) of deposited lithium has increased with charge passed during plating, indicating a faster growing from the base. In addition, the dendritic or mossy lithium has also been observed when various high current densities (25, 12.5, and 6.3 mA cm–2) are applied in different cycles, showing a severe dendritic lithium formation that could be induced by inhomogeneous current distribution. The clear structure of dead lithium is found after the cycling, which also shows a lower efficiency and higher hazard when a higher current density is applied. This work explores TXM as a use...

The microstructural stability of active-material particles is critical for maintaining the integrity of battery electrodes necessary for achieving high electrochemical performance. The correlation between the electrochemistry and structural evolution for the sodiation and desodiation of a Bi particulate anode was investigated using a combination of in operando synchrotron transmission X-ray microscopy and X-ray diffraction. Unique features not previously seen in the sodiation or lithiation of other alloying anodes were revealed. Specifically, an unprecedented serious delay in the crystal structure and microstructure transformation from NaBi to Na3Bi occurred. Microstructural evolution before the transformation is characterized by uniform and mild particle expansion without crack formation, and afterward by an abrupt and extensive fracturing of the particles. We demonstrate that the delayed structural transformation provides an opportunity to cycle the Bi particulate anode to high capacity while being immune to particle fracture or pulverization. The resistance to cracks and fractures over a wide sodiation depth is consistent with a high resistance to brittle fracture of NaBi predicted in the literature. The results may indicate a new direction for engineering fracture-free alloying anode materials for both Na-ion and Li-ion battery applications.

Low cost electrode materials are essential for the expansion of the applications of large-format Li-ion batteries (LIBs). Kerf-loss (KL) Si waste from the photovoltaic industry represents a low cost, high-purity Si source for the production of high capacity anodes of LIBs. Producing an energy storage device from solar-panel industry waste is a potential environment-friendly energy development. This study addressed the challenges of employing KL Si as high-capacity LIB anode. The abrasive SiC particle impurities in KL waste powder were used not only as a milling agent to reduce silicon particle size but also as mechanically and electrochemically robust pillars that resist microstructural degradation of the electrode caused by the expansion of Si during lithiation. High energy ball milling of Si with rigid SiC produced fused nanosilicon particles that were supported on micrometer-sized SiC; this resulted in substantially mitigated capacity fading. In addition, an effective conducting network was formed by i...

The microscopic pore structure is one of the most important factors to understand shale gas reservoirs. Recognized as a non-destructive method, nano-transmission X-ray microscopy (Nano-TXM) is sufficiently powerful to resolve nanometer pore structures and to quantify the effective network in shale. In this work, three dimensional (3D) pore networks of typical pore structures, such as organic matter pores (OM pores), interparticle pores (InterP pores), intraplatelet pores within clay aggregates (IntraP pores) and intercrystalline pores within pyrite (InterC pores), developing in Jiulaodong (JLD) formation shale in the Weiyuan 201 well (W201) in Sichuan Basin were reconstructed by Nano-TXM. Meanwhile, the pore morphology, pore size, porosity and interconnectivity were analyzed using Pore Network Modeling (PNM). The results indicated that the pore shape, pore size distribution, porosity and interconnectivity varied between the four pore types. Nanometer pores ranging from 150 nm to 1000 nm dominate the OM pores in the samples. However, pores with a sheet-like structure that are larger than 1000 nm are mainly found in InterP and IntraP pores. OM pores and InterP pores have larger porosities (35% and 23.7%, respectively) than the other two pore types. OM pores, InterP pores and InterC pores exhibit good and homogenous 3D connectivity, whereas IntraP pores have good extensity parallel to the clay mineral orientation but have no connectivity perpendicular to it. The 3D morphology and pore parameters suggest that the nano-pores in OM and InterC pores store absorbed gas and might be connected by micropores that existed in InterP and IntraP pores. The characterization of the pore structure in shale samples provides useful information for shale gas development.

This paper presents an inkjet printing and filling process to produce $250\mu \mathrm{m}$ deep Ag-based fully filled through silicon vias with the aspect ratio of via depth vs. diameter up to 5. With the optimization of the printing pattern, humidity control, and silver mirror reaction, the Ag TSV subjected to 400°C thermal anneal for 60 mins can exhibit a resistivity of $26\mu\Omega\bullet \mathrm{cm}$ , the lowest resistivity and highest AR ever reported. Process simplicity and no need of metal liners make the technique with great potential for 3D microsystem integration.

Microstructural investigations were conducted to better understand the poor settling and dewatering of a clay mineral-rich slurry. Investigations of the flocculated microstructure in a 2.5 wt% smectite clay suspension in a moderately salty aqueous solution were conducted with the aid of a synchrotron-powered transmission X-ray microscope and a cryo-transmission electron microscope. These investigations enabled the study of the clay particles’ mutual configuration in three-dimensional arrangements within natural water environments without drying the samples. The observed microstructure was similar to that observed in Wyoming smectite suspensions. A transition was observed from the “net of flakes” in monovalent cations in solution to the “Bander” model, when bivalent cations were present in the solution. As these structural models differ significantly from each other, the physical properties of the resulting gel also demonstrated remarkable diversities. These findings may play a crucial role in understanding smectite gel behaviour and its aggregating nature, which are of interest across many industries and are important in designing the most suitable technology to deal with colloidal stability.

Particle space arrangement is a very important factor that determines the physico-mechanical properties of soil. Formations of three-dimensional (3D) structured networks within gelled or flocculated suspension may prevent clay particles and aggregates from building dense aggregates and by encapsulate water within the ultrathin and closed void network, lead to poor sludge dewatering. To better understand the water retention behaviour of smectite-rich clays, a microstructural investigation was conducted on Amcol Australian bentonite in aqueous suspension in near the liquid limit (LL) and the plastic limit (PL). The investigation was conducted with the aid of synchrotron-powered transmission X-ray microscope tomography (TXM), with subsequent computer reconstruction. Images from the microscopy studies were statistically analysed using the STatistical IMage ANalysing (STIMAN) system. The study found that clay particles form a spanned framework in which mineral particles, aggregates and water-filled voids assemble as hierarchic structural elements. The size of these structural elements was larger in the water suspension and subsequently became smaller as an effect of water loss in the suspension > liquid and > plastic limit conditions. The clay suspension structure was almost isometric, with a low anisotropy coefficient: K α – 9%. This parameter increased to K α – 17% in (LL) and increased further in (PL) conditions to K α – 35%. Voids within structural elements were much smaller than the water filled inter-flock voids, with their median diameter 140 nm (suspension), 120 nm (LL) and 90 nm (PL). Significant differences in Atterberg limits values were observed between powder freshly mixed with water and a seasoned sample. Therefore, careful consideration of the sample mineral composition, clay content and genesis must be given due to preparation for geotechnical examination.

An approach for nano scale 3-D tomography of organic carbon (OC) and associated mineral nano particles was developed to illustrate their spatial distribution and boundary interplay, using synchrotron-based transmission X-ray microscopy (TXM). The proposed 3-D tomography technique was first applied to in-situ observation of a lab-made consortium of black carbon (BC) and nano mineral (TiO2, 15 nm), and its performance was evaluated under dual-scan absorption contrast and phase contrast modes. Then this novel tool was successfully applied to a natural OC-mineral consortium from high mountain soil at a spatial resolution down to 60 nm, showing the fine structure and boundary of OC, distribution of abundant minerals at nano size, and in-situ 3-D organo-mineral association. The stabilization of aged natural OC was found attributed to the physical protection of Fe-containing minerals (Fe oxyhydroxides including ferrihydrite, goethite, and lepidocrocite) of nano size, and the strong organo-mineral complexation. The sorption of OC (and cation) to Fe oxyhydroxides through organo-mineral multiple complex bonds such as ligand exchange could occupy and consume their respective reactive surface sites, tune down their activity and enhance their respective stabilization. The ubiquitousness and abundance of mineral nano particles, and their high heterogeneity in natural environment could have been seriously underestimated by traditional study approach. Our in-situ description of organo-mineral interplay at nano scale provides direct evidence to substantiate the importance of mineral physical protection for OC long term stabilization. Mineral physical protection for OC stabilization may be more important than previous understanding. This high resolution 3-D tomography tool is promising for new insight on the interior 3-D structure of micro-aggregates, in-situ organo-mineral interplay, and the fate of mineral nano particles including heavy metals in natural environment.

The dynamics of polysulfide (PS) dissolution and re-deposition during electrochemical charge/discharge of the lithium-sulfur (Li–S) cell has been investigated in a quantitative manner based on in-operando transmission X-ray microscopy (TXM) analysis of dimensional variations of S particles in working cells that have been subjected to different depths of charge/discharge. Extensive shrinkage and expansion of S particles have been observed to result from PS dissolution and re-deposition, respectively. The dissolution rate of PS is found to have complex dependence on the Li content, being significantly higher for the stoichiometries of LiS8 and Li2S4 than those between Li2S8 and Li2S6. PS re-deposition is nucleation-limited, leading to considerable aggregation of the S-containing active mass and enormous dimensional variations of active particles. These two consequences may impose threat to the cycle stability of the electrode. Possible benefit of introducing favorable nucleation sites is discussed.

When an earthquake occurs, magnetic minerals are formed in the gouge under the combined action of frictional heating and fluid. Generally, the gouge is altered, and a detailed analysis of neoformed minerals is difficult. The Taiwan Chelungpu fault Drilling Project provided continuous records of the active Chelungpu fault gouges. By analyzing the magnetic parameters along the 16 cm thick gouge which houses the principal slip zone of the 1999 Chi-Chi earthquake (Mw 7.6), we observed a 4 cm shift between the maximum of magnetic susceptibility and the maximum of remanence. The maximum magnetic susceptibility is localized along the principal slip zone. The main identified magnetic minerals are magnetite and goethite, which have very different magnetic parameters. We propose that the maximum of the concentration of magnetite and goethite corresponds to the maximum of magnetic susceptibility and remanence, respectively. By modeling the concentration of these two magnetic minerals, we explain satisfactorily the profiles of magnetic susceptibility and remanence. This quantitative modeling indicates that ~200 ppmv of magnetite formed in the principal slip zone and its main contact area. Similarly, ~1% of goethite is formed in the center of the gouge, where the fluids are more enriched in iron. We propose that the magnetite and goethite are formed and altered during seismic cycles. Key Points Investigate the magnetic mineral assemblage in the Chi-Chi fault gougeClarify the distribution of goethite and magnetite in the gougePropose a model for goethite and magnetite distributions within the gouge

Herein, Cr deposition and poisoning behavior at the commonly used (La0.6Sr0.4)(Co0.2Fe0.8) O3-delta (LSCF) electrode of solid oxide fuel cells (SOFCs) is investigated. Three-dimension (3D) microstructure evolution of the porous electrode caused by Cr deposition during the polarization test at 900 degrees C in the presence of a Fe-Cr metallic interconnect is characterized for the first time using the transmission X-ray microscopy (TXM) technique. The results indicate that a layer of solid Cr deposits similar to 1.7 mu m in thickness is formed on the electrode surface, significantly reducing the linear porosity to similar to 2% in the surface region from similar to 25% in the bulk, which explains the retarded gas diffusion process at the LSCF electrode after Cr deposition. The well-established relationship between the macroscopic performance degradation and the microstructure evolution confirms the promising application of TXM technique for in-depth study of the degradation phenomenon at the electrode of SOFCs. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

A nondestructive tomographic technique was used to determine the crystallographic information of colloidal crystals comprising of polystyrene (PS) microspheres, as well as their silver inverse opals. The properties of the colloidal crystals, such as defects, grain size, grain boundaries, stacking sequence, and grain orientation, were determined using the full field transmission X-ray microscopy (TXM) with a spatial resolution of 50 nm. The PS microspheres (500–750 nm) which underwent a vertical electrophoresis process to form a face-centered cubic (fcc) close-packed structure with an ABCABC packing sequence. In addition, the colloidal crystal exhibited multiple grains, and an orientation variation of 6.1° in the stacking direction between two neighboring grains.

The paper presents a low temperature (with 60 °C) inkjet printing and filling process to realize low resistive Ag TSV (Through Substrate Vias) with the aspect ratio of via depth vs. diameter from 2 to 5 in a SU-8 substrate potential for flexible microsystem packaging applications. Combining humidity control and layer-by-layer Ag mirror reaction, the proposed process technology can accomplish a fully filled TSV with the lowest electrical resistivity of ∼450 μΩ•cm in comparison with the prior printing and filling technologies.

A mold is designed to create various pre-strain levels in poly(ethylene) terephthalate (PET) substrates before the deposition of TiO 2 film to imitate the deposition process on a cylindrical drum. Four pre-strain levels, namely 0%, 2%, 4%, and 6%, are used in the preparations of TiO 2 /PET specimens to investigate the effects of pre-strain on the film morphology and the stress/strain formed in the PET substrate on the contact angle. Finite element analyses for stress/strain in the PET substrate are carried out, including that for the contact pressure distribution over the contact surface between the PET substrate and the partial-arc cylindrical drum. A significant increase in the stress/strain is produced with increasing pre-strain of the PET substrate. The mean length and width of the voids formed in the TiO 2 /PET specimens strongly depend on the specimen position. An increase in the pre-strain, and thus the stress/strain, results in an increase of the mean width and length of voids. The contact angle increases with decreasing stress/strain of the PET substrate. An increase in the pre-strain of the PET substrate leads to a reduction in the contact angle. Bent PET specimens have wavier surface profiles compared to that of the as-received PET. The mean amplitude value decreases with increasing pre-strain. The effect of stress on the contact angle formed on the wavy surface can be explained by the Wenzel equation. The decrease in the contact angle can enhance the absorption of the TiO 2 film, and thus increase the distance between two adjacent valleys in the porous TiO 2 film. The extrusions/intrusions in the porous PET after bending and the different stress/strain distributions over the PET substrate cause drastic changes in the local morphology of the TiO 2 /PET specimen.

The mechanism of capacity fade of the Li2MnO3·LiMO2 (M = Li, Ni, Co, Mn) composite positive electrode within a full cell was investigated using a combination of operando neutron powder diffraction and transmission X-ray microscopy methods, enabling the phase, crystallographic, and morphological evolution of the material during electrochemical cycling to be understood. The electrode was shown to initially consist of 73(1) wt % R3̅m LiMO2 with the remaining 27(1) wt % C2/m Li2MnO3 likely existing as an intergrowth. Cracking in the Li2MnO3·LiMO2 electrode particle under operando microscopy observation was revealed to be initiated by the solid-solution reaction of the LiMO2 phase on charge to 4.55 V vs Li(+)/Li and intensified during further charge to 4.7 V vs Li(+)/Li during the concurrent two-phase reaction of the LiMO2 phase, involving the largest lattice change of any phase, and oxygen evolution from the Li2MnO3 phase. Notably, significant healing of the generated cracks in the Li2MnO3·LiMO2 electrode particle occurred during subsequent lithiation on discharge, with this rehealing being principally associated with the solid-solution reaction of the LiMO2 phase. This work reveals that while it is the reduction of lattice size of electrode phases during charge that results in cracking of the Li2MnO3·LiMO2 electrode particle, with the extent of cracking correlated to the magnitude of the size change, crack healing is possible in the reverse solid-solution reaction occurring during discharge. Importantly, it is the phase separation during the two-phase reaction of the LiMO2 phase that prevents the complete healing of the electrode particle, leading to pulverization over extended cycling. This work points to the minimization of behavior leading to phase separation, such as two-phase and oxygen evolution, as a key strategy in preventing capacity fade of the electrode.

Effective flocculation and dewatering of mineral processing streams containing clays are microstructure dependent in clay-water systems. Initial clay flocculation is crucial in the design and for the development of a new methodology of gas exploitation. Microstructural engineering of clay aggregates using covalent cations and Keggin macromolecules have been monitored using the new state of the art Transmission X-ray Microscope (TXM) with 60 nm tomography resolution installed in a Taiwanese synchrotron. The 3-D reconstructions from TXM images show complex aggregation structures in montmorillonite aqueous suspensions after treatment with Na+, Ca2+ and Al13 Keggin macromolecules. Na-montmorillonite displays elongated, parallel, well-orientated and closed-void cellular networks, 0.5–3 µm in diameter. After treatment by covalent cations, the coagulated structure displays much smaller, randomly orientated and openly connected cells, 300–600 nm in diameter. The average distances measured between montmorillonite sheets was around 450 nm, which is less than half of the cell dimension measured in Na-montmorillonite. The most dramatic structural changes were observed after treatment by Al13 Keggin, aggregates then became arranged in compacted domains of a 300 nm average diameter composed of thick face-to-face oriented sheets, which forms porous aggregates with larger intra-aggregate open and connected voids.

Sn-containing compounds are potential high-capacity anode materials for Li-ion batteries. They, however, suffer from significant dimensional variations during electrochemical lithiation and delithiation, causing cycling instability. Understanding the dynamics of these deformation processes may provide valuable information in the establishment of viable high-energy anodes. In this paper, the evolution of interior microstructures of two types of Sn-containing particles, including Sn and SnSb, during initial cycles of electrochemical lithiation/delithation has been revealed by in situ synchrotron transmission X-ray microscopy, complemented by in situ synchrotron X-ray diffraction to provide phase information. The microstructures and deformation rates are shown to depend on particle composition, size, and alloy stoichiometry with Li. During first lithiation, both particles exhibit core (metal)–shell (lithiated compounds) interior structures. Initial formation of a dense surface layer containing LixSn phases o...

Cubic and octahedral Cu2O nanocrystals and Au–Cu2O core–shell heterostructures are used as sacrificial templates for the growth of Cu2S nanocages and Au–Cu2S core–cage structures. A rapid sulfidation process involving a surface reaction of Cu2O nanocrystals with Na2S, followed by etching of the Cu2O cores with HCl solution for ≈5 sec, results in the fabrication of Cu2S cages with a wall thickness of 10–20 nm. Transmission electron microscopy characterization reveals the formation of crystalline walls and the presence of ultrasmall pores with sizes of 1 nm or less. Formation of Cu2O–Cu2S core–shell structures and their conversion into Cu2S cages is verified by UV–vis absorption spectroscopy. X-ray photoelectron spectra further confirm the composition of the cages as Cu2S. The entire hollowing process via the Kirkendall effect is recorded using in-situ transmission X-ray microscopy. After shell formation, continuous ionic diffusion removes the interior Cu2O. Intermediate structures with remaining central Cu2O portions and bridging arms to the surrounding cages are observed. The nanocages are also shown to allow molecular transport: anthracene and pyrene penetration into the cages leads to enhanced fluorescence quenching immediately upon adsorption onto the surfaces of the encapsulated gold nanocrystals.

The interior microstructures of Sn particles developed during electrochemical lithiation/de-lithiation have been revealed by in situ X-ray transmission microscopy (TXM). The Li-alloying particles exhibited the formation of core–shell internal structure along with crack formation within the lithiated zone during the first lithiation. The extent and speed of the expansion process was shown to be a strong function of particle size. Upon completion of the first de-lithiaiton, the particles only partially (∼10%) contracted, while re-crystallization of Sn continued to take place within the interior of the particles during a following idle period. The re-crystallization process alleviated the pulverization problem and led to the formation of porous Sn particles, which exhibited remarkably attenuated dimensional variations during subsequent cycles. Keywords: Transmission X-ray microscopy, Alloying anode, Tin, Li-ion battery

At the National Synchrotron Radiation Research Center (NSRRC), which operates a 1.5 GeV storage ring, a dedicated small-angle X-ray scattering (SAXS) beamline has been installed with an in-achromat superconducting wiggler insertion device of peak magnetic field 3.1 T. The vertical beam divergence from the X-ray source is reduced significantly by a collimating mirror. Subsequently the beam is selectively monochromated by a double Si(111) crystal monochromator with high energy resolution (DeltaE/E approximately 2 x 10(-4)) in the energy range 5-23 keV, or by a double Mo/B4C multilayer monochromator for 10-30 times higher flux ( approximately 10(11) photons s(-1)) in the 6-15 keV range. These two monochromators are incorporated into one rotating cradle for fast exchange. The monochromated beam is focused by a toroidal mirror with 1:1 focusing for a small beam divergence and a beam size of approximately 0.9 mm x 0.3 mm (horizontal x vertical) at the focus point located 26.5 m from the radiation source. A plane mirror installed after the toroidal mirror is selectively used to deflect the beam downwards for grazing-incidence SAXS (GISAXS) from liquid surfaces. Two online beam-position monitors separated by 8 m provide an efficient feedback control for an overall beam-position stability in the 10 microm range. The beam features measured, including the flux density, energy resolution, size and divergence, are consistent with those calculated using the ray-tracing program SHADOW. With the deflectable beam of relatively high energy resolution and high flux, the new beamline meets the requirements for a wide range of SAXS applications, including anomalous SAXS for multiphase nanoparticles (e.g. semiconductor core-shell quantum dots) and GISAXS from liquid surfaces.

The unusual behavior of smectites, the ability to change volume when wetted (swelling) or dried (shrinking), makes soil rich in smectites very unstable and dangerous for the building industry because of the movement of building foundations and poor slope stability. These macroscopic properties are dominated by the structural arrangement of the smectites' finest fraction. Here, we show in three dimensions how the swelling phenomenon in smectite, caused by a combination of hydratation and electrostatic forces, may expand the dry smectite volume not 10-fold, as previously thought, but to more than 1000-fold. A new technique, transmission X-ray microscopy, makes it possible to investigate the internal structure and 3-D tomographic reconstruction of clay aggregates. This reveals, for the first time, the smectite gel arrangement in the voluminous cellular tactoid structure within a natural aqueous environment.

The utilization of new transmission X-ray microscopy (TXM) using the synchrotron photon source enable for the first time the study in three dimensions microsize clay particles in aggregates in their natural aqueous environment. This technique makes possible remarkable accurate images of nanosize mineral interparticle structure which forms a new nanocomposite. The Birdwood kaolinite/LDH aggregates observed in the TXM are much more compact than observed before in pure Birdwood kaolinite suspension and similar to aggregates formed after treatment by positively charged surfactant. Kaolinite/LDH aggregates in water reveal complex structure of larger kaolinite platelets connected together by gelled nanoparticles which are most probably LDH colloidal plates. Comparisons of the transmission electron microscope (TEM) and TXM techniques show similarities in particle morphology. The ability to study particles and aggregates in their natural aqueous environment and in 3-dimensions make this technique superior to the TEM technique.

The relationship between tooth form and dietary preference is a crucial issue in vertebrate evolution. However, the mechanical properties of a tooth are influenced not only by its shape but also by its internal structure. Here, we use synchrotron transmission X-ray microscopy to examine the internal microstructures of multiple dinosaur teeth within a phylogenetic framework. We found that the internal microstructures of saurischian teeth are very different from advanced ornithischian teeth, reflecting differences in dental developmental strategies. The three-tissue composition (enamel–mantle dentin–bulk dentin) near the dentinoenamel junction (DEJ) in saurischian teeth represents the primitive condition of dinosaur teeth. Mantle dentin, greatly reduced or absent from DEJ in derived ornithischian teeth, is a key difference between Saurischia and Ornithischia. This may be related to the derived herbivorous feeding behavior of ornithischians, but interestingly, it is still retained in the herbivorous saurischian sauropods. The protective functions of mantle dentin with porous microstructures between enamel and bulk dentin inside typical saurischian teeth are also discussed using finite-element analysis method. Evolution of the dental modifications in ornithischian dinosaurs, with the absence of mantle dentin, may be related to changes in enamel characteristics with enamel spindles extending through the DEJ.

Two-photon double-resonant photoionization of Ar and Xe to their autoionizing states lying between the 2 P 3/2 and 2 P 1/2 ionic thresholds was carried out with the combination of a laser system and VUV synchrotron radiation from the storage ring at NSRRC. Tuning this radiation of narrow width to a selected Rydberg state was followed by excitation to even-parity levels of autoionization states with a tunable Ti:sapphire laser. The experimental results show two-photon ionization spectra of argon with a large ratio of signal to noise. When the intermediate state 3p 5 ( 2 P 1/2 )3d′ [3/2] 1 of argon is excited, the spectrum shows a weak continuous background and three autoionizing series 3p 5 n f′[5/2] 2 ( n = 9–20), 3p 5 n p′ [3/2] 2 and 3p 5 n p′ [1/2] 0 . The latter two series were resolved partly because of improved resolution in this work and partly because their relative intensities vary with the relative polarization of two excitation sources.

The unusual morphology and internal structure of bubbles within lunar regolith impact glasses have been studied using traditional scanning electron microscopy and the novel technique transmission X-ray microscopy (TXM), with 3D tomography reconstruction. Here, we show the previously unknown phenomenon of building a highly porous cellular structure within bubbles in glassy particles of the dust fraction of lunar regolith. Vesicles within studied lunar glasses are filled in with submicron-sized particles as shown in the presented micrograph. These particles consist of glass nano in size elements. What is shown in the TXM tomography reconstruction anaglyph demonstrates cellular-like, 3D structure where oblique probably glassy fine particles down to 100 nm in diameter build chains of sophisticated network. It also may be suggested that submicron and nano-sized grains present in lunar regolith are the result of particle liberation from broken glassy vesicles. This liberation takes place when regolith is exposed to constant impact pulverisation. Liberated particles are permanently enriching lunar soil in the finest soil constituent. This constituent presence in lunar regolith may be responsible for the unusual behaviour of lunar material. This unusual constituent of lunar regolith and its properties have to be better understood before our permanent lunar exploration begins.

Hypothesis Particle space arrangement is a very important factor that determines the physico-mechanical properties of soil. Formations of three-dimensional (3D) structured networks within gelled or flocculated suspension may prevent clay particles and aggregates from settling under gravity force and by encapsulate water within such a network, lead to poor sludge dewatering. To better understand this phenomenon, a microstructural investigation of a smectite clay (SWy2) suspension was conducted. Experiments SWy-2 was diluted in water and a moderately salty aqueous solution and was studied with the aid of a synchrotron-powered transmission X-ray microscope (TXM) and cryogenic transmission electron microscope (Cryo-TEM). Observations of mutual particle arrangement in 3D spaces were conducted within a natural water environment after vitrification without drying. Findings A new type of micro-architecture in particle space arrangement was observed. Smectite flakes were mostly in edge-to-edge (EE) contact and formed a 3D network, confirming a “net of flakes” structural model. Clay particles form a complex and multi-hierarchic flocculated structure with characteristic cellular chained networking. Chained aggregates build cellular elements, encapsulating water inside closed voids. Increasing ionic strength results in the development of multi-hierarchic voids categories, with most water retained within nano-pores.

Cubic, rhombic dodecahedral, octahedral, and corner-truncated octahedral gold nanocrystals with sizes of tens of nanometers have been used as building blocks to form micrometer-sized supercrystals by slowly evaporating a water droplet on a substrate placed in a moist environment. Drying the droplet at 90 °C was found to yield the best supercrystals. Supercrystals were evenly distributed throughout the entire substrate surface originally covered by the droplet. Diverse supercrystal morphologies have been observed. Nanocubes formed roughly cubic supercrystals. Rhombic dodecahedra were assembled into truncated triangular pyramidal supercrystals. Rhombic dodecahedral, octahedral, and hexapod-shaped supercrystals were generated through the assembly of octahedra. Corner-truncated octahedra formed tetrapod-shaped supercrystals at room temperature, but octahedral, truncated triangular pyramidal, and square pyramidal supercrystals at 90 °C. Nanocrystal assembly was found to be strongly shape-guided. Expulsion of excess surfactant to the surfaces of supercrystals suggests that responsive adjustment of surfactant concentration during particle assembly mediates supercrystal formation. Transmission X-ray microscopy and optical microscopy have been employed to follow the supercrystal formation process. Surprising rotational water current near the droplet perimeter carrying the initially formed supercrystals has been observed. Supercrystals appear to grow from the edge of the droplet toward the central region. Supercrystals assembled from octahedra inherently contain void spaces and possibly connected channels. The mesoporosity of these supercrystals was confirmed by infiltrating H(2)PdCl(4) into the supercrystal interior and reducing the precursor to form Pd nanoparticles. The embedded Pd particles can still catalyze a Suzuki coupling reaction, demonstrating the application of these supercrystals for molecular transport, sensing, and catalysis.

[1] During an earthquake, physical and chemical transformations lead to alteration and formation of minerals in the gouge layer. Altered and neoformed minerals can be used as tracers of some earthquake processes. In this study, we investigate pyrite and magnetic minerals within the host Chinshui siltstone and the 16-cm-thick gouge. This gouge hosts the principal slip zone of Chi-Chi earthquake (Mw7.6, 1999). In the Chinshui siltstone, pyrite framboids of various sizes and euhedral pyrite are observed. The magnetic mineral assemblage comprises stoichiometric magnetite, greigite, and fine-grained pyrrhotite. The pyrite content is generally reduced in the gouge compared to the wall rock. The magnetic mineral assemblage in the gouge consists of goethite, pyrrhotite, and partially oxidized magnetite. The pyrrhotite, goethite and some magnetite are neoformed. Pyrrhotite likely formed from high temperature decomposition of pyrite (>500°C) generated during co-seismic slip of repeated earthquakes. Goethite is inferred to have formed from hot aqueous co-seismic fluid (>350°C) in association with the 1999 Chi-Chi event. Elevated fluid temperatures can also explain the partial alteration of magnetite and the retrograde alteration of some pyrrhotite to pyrite. We suggest that characterization of neoformed magnetic minerals can provide important information for studying earthquake slip zones in sediment-derived fault gouge.

International audience; During an earthquake, the physical and the chemical transformations along a slip zone lead to an intense deformation within the gouge layer of a mature fault zone. Because the gouge contains ferromagnetic minerals, it has the capacity to behave as a magnetic recorder during an earthquake. This constitutes a conceivable way to identify earthquakes slip zones. In this paper, we investigate the magnetic record of the Chelungpu fault gouge that hosts the principal slip zone of the Chi-Chi earthquake (Mw 7.6, 1999, Taiwan) using Taiwan Chelungpu-fault Drilling Project core samples. Rock magnetic investigation pinpoints the location of the Chi-Chi mm-thick principal slip zone within the 16-cm thick gouge at ~1 km depth. A modern magnetic dipole of Earth magnetic field is recovered throughout this gouge but not in the wall rocks nor in the two other adjacent fault zones. This magnetic record resides essentially in two magnetic minerals; magnetite in the principal slip zone, and neoformed goethite elsewhere in the gouge. We propose a model where magnetic record: 1) is preserved during inter-seismic time, 2) is erased during co-seismic time and 3) is imprinted during post-seismic time when fluids cooled down. We suggest that the identification of a stable magnetic record carried by neoformed goethite may be a signature of friction-heating process in seismic slip zone.

The influence of smectite addition on kaolinite suspensions in water was investigated by transmission X-ray microscopy (TXM) and Scanning Electron Microscopy (SEM). Sedimentation test screening was also conducted. Micrographs were processed by the STatistic IMage Analysing (STIMAN) program and structural parameters were calculated. From the results of the sedimentation tests important influences of small smectite additions to about 3wt.% on kaolinite suspension flocculation has been found. In order to determine the reason for this smectite impact on kaolinite suspension, macroscopic behaviour micro-structural examination using Transmission X-ray Microscope (TXM) and SEM has been undertaken. TXM & SEM micrographs of freeze-dried kaolinite-smectite suspensions with up to 20% smectite showed a high degree of orientation of the fabric made of highly oriented particles and greatest density when 3wt.% of smectite was added to the 10wt.% dense kaolinite suspension. In contrast, suspensions containing pure kaolinite do not show such platelet mutual orientation but homogenous network of randomly oriented kaolinite platelets. This suggests that in kaolinite-smectite suspensions, smectite forms highly oriented basic framework into which kaolinite platelets may bond in face to face preferential contacts strengthening structure and allowing them to show plastic behaviour which is cause of platelets orientation.

The aggregate structure which occurs in aqueous smectitic suspensions is responsible for poor water clarification, difficulties in sludge dewatering and the unusual rheological behaviour of smectite rich soils. These macroscopic properties are dictated by the 3D structural arrangement of smectite finest fraction within flocculated aggregates. Here, we report results from a relatively new technique, transmission X-ray microscopy (TXM), which makes it possible to investigate the internal structure and 3D tomographic reconstruction of the smectite clay aggregates modified by Al(13) Keggin macro-molecule [Al(13)(O)(4)(OH)(24)(H(2)O)(12)](7+). Three different treatment methods were shown resulted in three different micro-structural environments of the resulting flocculation. In case of smectite sample prepared in Methods 1 and 3 particles fall into the primary minimum where Van der Waals forces act between FF oriented smectite flakes and aggregates become approach irreversible flocculation. In case of sample prepared using Method 2, particles contacting by edges (EE) and edge to face (EF) orientation fell into secondary minimum and weak flocculation resulted in severe gelation and formation of the micelle-like texture in fringe superstructure, which was first time observed in smectite based gel.

1.611 0.011, 1.683 0.013, 1.688 0.010, and 0.016 0.005, respectively. Our values are in excellent agreement with theoretical prediction. The spectral line shapes of autoionizing Rydberg states are analyzed with a Beutler-Fano profile. Reduced autoionization linewidths for the np1 / 20n =1 1–1 6 series vary in the range 2549– 4145 cm �1 , and the nf5 / 22n =9–1 1 series in 186– 247 cm �1 in reasonable agreement with theoret

This paper reports new application of new transmission X-ray microscopy powered by a synchrotron source for the study of aqueous based clay suspensions. This paper delineates the advantages and limitations of this method. The tested transmission X-ray microscopy (TXM) technique has shown good agreement with the cryo-stage SEM technique. The spacial resolution of this TXM technique is 60 nm and clay particles with diameter below 500 nm are clearly visible and their pseudohexagonal symmetry is recognizable in detail. It is clearly demonstrated the methodology of implementing TXM to study aqueous based clay suspensions that are close to approximately 60 nm tomographic resolution. The technique enables us to study discrete structure of clay suspensions in water and within aggregates. This has never been previously possible. Larger crystals, more compact aggregates and less colloidal fraction present in kaolinite from Georgia has impact on faster settling and gelling in denser suspension than for Birdwood kaolinite in which colloidal particles create gel-like networking in less dense aqueous suspension.

A transmission X‐ray microscope (TXM) has been installed at the BL01B beamline at National Synchrotron Radiation Research Center in Taiwan. This state‐of‐the‐art TXM operational in a range 8‐11 keV provides 2D images and 3D tomography with spatial resolution 60 nm, and with the Zernike‐phase contrast mode for imaging light materials such as biological specimens. A spatial resolution of the TXM better than 30 nm, apparently the best result in hard X‐ray microscopy, has been achieved by employing the third diffraction order of the objective zone plate. The TXM has been applied in diverse research fields, including analysis of failure mechanisms in microelectronic devices, tomographic structures of naturally grown photonic specimens, and the internal structure of fault zone gouges from an earthquake core. Here we discuss the scope and prospects of the project, and the progress of the TXM in NSRRC.

The Taiwan Contract Beamline BL12XU at SPring‐8 is designed for inelastic X‐ray scattering (IXS) experiments. DCS is a powerful technique capable of probing the dynamic behavior and electronic structure of materials under high pressure. The state‐of‐the‐arts technology to generate static high pressure up to mega‐bar range uses diamond anvil cells (DAC). The allowed volume of the sample in DAC scales inversely with the pressure and is limited to the order of 1 × 10−3 mm3. In order to utilize such a device to explore the interesting phenomena under high pressure, we have designed a micro‐focusing system using a set of KB mirrors, which is compatible with the existing optical system of BL12XU. Realistic ray‐tracing results indicate that the system can achieve a focus of 10 μm × 5.3 μm(H × V) with a total efficiency of about 86%. The improved focus is expected to substantially enhance the experimental capability of BL12XU for high‐pressure research.