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Polymetallic ferromanganese nodules (PMNs) in the Clarion-Clipperton Zone (CCZ) exhibit significant spatial variability in chemical composition, which complicates exploration efforts and increases associated costs. The primary factors driving this spatial variability remain unclear due to limited understanding of the growth history of these nodules. This study investigated the internal structure and elemental distributions of PMNs from both the eastern and western CCZ using a range of in-situ techniques, including high-resolution element mapping and chemical analysis, to characterize the compositional differences and growth processes of the nodules. Analysis of Nodule BC06 from the eastern CCZ reveals a decreasing Mn/Fe ratio from the inner part (Layer I) to the outer part (Layer II). In contrast, Nodule BC1901 from the western CCZ consists of three layers, with the Mn/Fe ratio increasing from Layer I to Layer II and then decreasing from Layer II to Layer III. Discrimination diagrams indicate that both nodules formed through hydrogenetic and diagenetic processes, with Nodule BC06 showing stronger diagenetic influences. Variations in diagenetic effects from core to rim suggest different geochemical controls in the two regions. In the eastern CCZ, compositional changes are mainly driven by the movement of PMNs away from the equatorial high-productivity zone. In the western CCZ, the variability in deep-water ventilation and the intensity of Antarctic Bottom Water are the key factors influencing nodule composition. These findings enhance our understanding of the growth history and spatial variability of PMNs in the CCZ and provide valuable insights for future resource evaluation. [ABSTRACT FROM AUTHOR]

Underground pyrolysis of tar-rich coal is a green and low-carbon technology that effectively extracts oil and gas resources from coal. It represents the forefront of clean and low-carbon utilization of coal. The nano-pores present in coal play a vital role in the adsorption and desorption of tar and gas during the underground pyrolysis process. Therefore, understanding the evolution of nano-pore structure under underground pyrolysis conditions is a key scientific issue for enhancing the oil and gas yield of tar-rich coal through this process. To address this, the China Spallation Neutron Source (CSNS) - Small-Angle Neutron Scattering (SANS) technique was employed to simulate the in-situ pyrolysis environment of coal seams. This allows for the quantitative characterization of the scattering intensity, average pore size, and fractal dimension evolution of nano-pores in tar-rich coal in different heating rates and temperatures under unconfined pressure conditions. The complementary physical characterization methods such as physical adsorption (BET), thermogravimetric analysis (TG), and scanning electron microscopy (SEM) were also utilized. The research findings reveal the evolution of nano-pore structure characteristics during the underground pyrolysis of tar-rich coal. The research results demonstrate that during the underground pyrolysis process, the average pore size of nano-pores gradually increases with the rise in temperature. Nanopore development is relatively slow during the pyrolysis drying and degassing stage ( < 300 ℃), while the most significant growth occurs during the active stage (300−500 ℃), resulting in a 57.1% increase. Subsequently, nanopore development slows down during the secondary degassing stage. Importantly, it was observed that the low-medium-high temperature (≤800 ℃) pyrolysis conditions does not cause any significant changes in the surface fractal dimension (Ds) of tar-rich coal. Based on SANS spectroscopy analysis, it was discovered that the distribution of nano-pores in tar-rich coal during the pyrolysis process exhibits isotropic characteristics. This suggests that the pyrolysis reaction does not impact the directional development of nanopores in this experimental samples. Furthermore, a comparison between different heating rates (5 ℃/min and 20 ℃/min) reveals minimal influence on the average pore size and fractal dimension of nano-pores during underground pyrolysis of tar-rich coal. Notably, under slower heating rates, tar-rich coal exhibits higher overall scattering intensity, indicating more substantial development of the nano-pore structure. This, in turn, facilitates the progress of the underground pyrolysis reaction. In addition to these findings, the CSNS-SANS technique proves advantageous over the conventional characterization methods such as BET. It enables the detection of closed pores within the samples and provides experimental conditions that closely resemble the in-situ environment, thereby ensuring more reliable results.

The in-situ EBSD analysis method was used to systematically study the effect of retained austenite characteristics on the phase transformation behavior of ferritic stainless steel after the quenching and partitioning （Q&P） process. The results show that the phase transformation behavior of retained austenite during deformation is related to its grain size， distribution， and morphology， and its influence degree is arranged in descending order. Compared with inter-martensitic austenite and inter-martensite-ferrite austenite， the trigeminal and twin austenite are more prone to martensitic transformation in the early stage of deformation. This is closely related to the different strains or stresses applied to different distributed retained austenites during deformation. Compared with large-sized austenite， small-sized austenite begins to transform in the later stage of deformation， which is helpful to prolong the uniform elongation. This may be due to the higher interfacial energy and average C content of small-sized austenite， and the need for larger macroscopic stress/strain to induce martensitic transformation due to the strengthening effect of fine grains. The elongated/equiaxed austenite is easy to transform in the early stage of deformation， while the transformation of thin film-retained austenite is mainly concentrated in the later stage of deformation， which is helpful to further improve plasticity. The different transformation behaviors are due to the differences in C and N content， as well as the presence of defects such as stacking faults， dislocations， and slip.

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Metal nitrides with extraordinary electrochemical characteristics established widespread applications in energy devices. Inspired by the recent research on promising heterostructured catalysts, the preparation of a nitride‐based heterostructure via a facile approach involving a one‐step nitridation process is revisited. An innovative Ni/Ni3N is decorated on nitrogen‐doped carbon (NC) and evaluated for its dual‐functionality as a catalyst in the electrochemical hydrogen evolution reaction (EHER) and the electrochemical oxygen evolution reaction (EOER). In contrast to Ni@NC and pristine NC, Ni/Ni3N@NC with the well‐constructed NC significantly enhanced its catalytic performance toward EHER and EOER in a water electrolyzer. The water electrolyzer consists of Ni/Ni3N@NC as both the anode and cathode achieve a current density of 10 mA cm−2 with a remarkably low voltage of 1.52 V. The designed catalyst takes full advantage of its heterostructure and ambipolar behavior leading to the presence of active sites for EOER and EHER, as confirmed by in‐situ Raman analysis. These results provide important guidance on designing an efficient and cost‐effective heterostructured dual‐functional catalyst as well as revealing the mechanism at the interface between the surface of an ambipolar catalyst and electrolyte. [ABSTRACT FROM AUTHOR]

Constrained thermal expansion and contraction during welding cause a compression-tension cycle and plastic deformation in the heat-affected zone, leading to work hardening. The nature of this hardening effect—isotropic or kinematic—determines the final local yield stress and thus affects the residual stress state. Therefore, mechanical hardening must be modeled correctly in welding simulations for accurately predicting welding residual stresses. Previous studies, relying on comparisons with experimental ex situ results, led to different recommendations regarding the choice of the hardening model and thus require clarification. In this work, the stress evolution in the heat-affected zone of a tungsten inert gas weld is studied in situ using energy-dispersive x-ray diffraction and a novel method of stress analysis based on crystallite anisotropy. Additionally, microstructural information is gathered through line profile analysis. Results are shown for both austenitic and ferritic high-alloy steels and compared to ex-situ results including a validation of the new method of stress analysis. Finally, conclusions on the nature of work hardening are drawn. [ABSTRACT FROM AUTHOR]

The outstanding tribological performance of transition metal dichalcogenides (TMDs) is attributed to their unique sandwich microstructure and low interlayer shear stress. This advantageous structure allows TMDs to demonstrate exceptional friction reduction properties. Furthermore, the incorporation of TMDs and amorphous carbon (a-C) in multi-layer structures shows excellent potential for further enhancing tribological and anti-oxidation properties. Amorphous carbon, known for its high ductility, chemical inertness, and excellent wear resistance, significantly contributes to the overall performance of these multi-layer coatings. To gain an in-depth understanding of the tribological mechanism and evolution of TMDs' multi-layer coatings, a dual in-situ analysis was carried out using a tribometer equipped with a 3D laser microscope and a Raman spectrometer. This innovative approach allowed for a comprehensive evolution of the tribological, topographical, and tribochemical characteristics of both single-layer WS2 and multi-layer WS2/C coatings in real time. The findings from the dual in-situ tribotest revealed distinct failure characteristics between the single-layer WS2 coating and the multi-layer WS2/C coating. The single-layer WS2 coating predominantly experienced failure due to mechanical removal, whereas a combination of mechanical removal and tribochemistry primarily influenced the failure of the multi-layer WS2/C coating. The tribological evolution process of these two coatings can be classified into four stages on the basis of their tribological behavior: the running-in stage, stable friction stage, re-deposition stage, and lubrication failure stage. Each stage represents a distinct phase in the tribological behavior of the coatings and contributes to our understanding of their behavior during sliding. [ABSTRACT FROM AUTHOR]

Polymetallic ferromanganese nodules (PMNs) in the Clarion-Clipperton Zone (CCZ) exhibit significant spatial variability in chemical composition, which complicates exploration efforts and increases associated costs. The primary factors driving this spatial variability remain unclear due to limited understanding of the growth history of these nodules. This study investigated the internal structure and elemental distributions of PMNs from both the eastern and western CCZ using a range of in-situ techniques, including high-resolution element mapping and chemical analysis, to characterize the compositional differences and growth processes of the nodules. Analysis of Nodule BC06 from the eastern CCZ reveals a decreasing Mn/Fe ratio from the inner part (Layer I) to the outer part (Layer II). In contrast, Nodule BC1901 from the western CCZ consists of three layers, with the Mn/Fe ratio increasing from Layer I to Layer II and then decreasing from Layer II to Layer III. Discrimination diagrams indicate that both nodules formed through hydrogenetic and diagenetic processes, with Nodule BC06 showing stronger diagenetic influences. Variations in diagenetic effects from core to rim suggest different geochemical controls in the two regions. In the eastern CCZ, compositional changes are mainly driven by the movement of PMNs away from the equatorial high-productivity zone. In the western CCZ, the variability in deep-water ventilation and the intensity of Antarctic Bottom Water are the key factors influencing nodule composition. These findings enhance our understanding of the growth history and spatial variability of PMNs in the CCZ and provide valuable insights for future resource evaluation.

The growth of coherently engineered porous bimetal (PBM) nanostructures shows great progress in electrochemical carbon dioxide (CO2) utilization. This is due to their remarkable catalytic and physicochemical merits that present an encouraging approach for CO2 conversion into valuable products (i.e., fuels and chemicals). Hence, this review presents recent advances in experimental, in-situ analysis and theoretical studies of PBM electrocatalysts, including PBM Cu-based and PBM Cu-free electrocatalysts, toward CO2 reduction reaction (CO2RR) and comprehend its fundamental mechanisms. Various synthesis strategies were utilized to construct PBM nanostructures with distinct compositions, morphology, and synergism for excellent CO2RR activity, stability and product selectivity. As corroborated by theoretical calculations that revealed beneficial electronic features and reaction routes with facile adsorption energies for reactant (CO2) and intermediate species on the various active sites of PBM nanostructures in easing the CO2RR. Future research efforts should establish robust framework for experimental, in-situ analysis, theoretical simulations and automated machine learning in developing next-generation electrochemical CO2 utilization technologies with PBM nanostructures. Finally, this study emphasizes the potential of PBM nanostructures for efficient electrochemical CO2 utilization and provides a pathway to sustainable and inexpensively viable carbon-neutrality.

To practically utilized the organometallic lead halide perovskites to optoelectronic devices and photoelectrochemical cells, numerous efforts have been utilized to obtain the perovskites with low-energy process with coverage of various inorganic mediums to improve stability against humidity. By utilizing ligand-assisted reprecipitation process, under ambient condition at room temperature, the dimensionally confined perovskite quantum dots in silica matrices (PQD@SiOx) were obtained, and they were stable under several months under the ambient condition. To apply the PQD@SiOx to the photoelectrochemical cells by introducing direct contact between PQD@SiOx and electrolyte, the material/photophysical properties under electrochemical conditions are necessary to be studied. However, the role of silica coverage to the electrochemical behaviors of the PQD cores in the silica medium were not yet studied. In this work, under the electrochemical conditions, the oxidative and reductive behaviors of the PQD@SiOx were studied. Also, through in-situ spectroelectrochemical study, the electrochemically induced irreversible deformation process were tracked. The findings of this study could be used to understand role of silica coverage and develop the strategy to improve the protecting behavior of the silica for the PQD cores to utilize into the photoelectrochemical cells.

Electrochemical nitrogen reduction reaction (eNRR) is recognized as an alternative green approach to the traditional energy-demanding and fossil-based catalytic processes (e.g. Haber Bosch). In this study, we implement eNRR in a proton exchange membrane (PEM) water electrolyzer in which nitrogen (N2) is fed in the cathode. This operation mode has been suggested as a way to overcome mass transfer limitations, however, there is a lack of developed evaluation protocols for appropriate product identification. Herein, we exemplify the spirit of the evaluation protocols for gas phase operation at the device level with a combination of online product analysis and isotopic labeling. Our protocol involves control experiments by replacing the cathodic N2 feed with (i) inert gas (i.e. Ar) and (ii) isotopic labeled 15N2 and by replacing the anodic water feed with isotopic labeled D2O. Taking advantage of the gas phase operation in the cathode product analysis is realized with online techniques i.e. quadrupole mass-spectrometer (QMS) and Fourier transform infrared (FTIR) spectrometer. This allows us to verify the production of diazene (N2H2) resulted from genuine N2 reduction, rather than from nitrogen-containing contaminants. Our methodology provides a pathway for how the false positive results can be eliminated in the gas phase study and a platform for follow-up studies using promising or exotic catalysts in the cathode, especially to validate the eNRR products or discover more products.

In the framework of the Helmholtz ARCHES project, a multitude of robots, including rovers and drones, were prepared for the autonomous exploration of a test site at the foothills of Mt. Etna, Sicily—a terrain resembling extraterrestrial locations such as the Moon. To expand the suite of tools and sensors available for the exploration and investigation of the test site, we developed a laser-induced breakdown spectroscopy (LIBS) instrument for the geochemical analysis of local geological samples. In alignment with the mission scenario, this instrument is housed in a modular payload box that can be attached to the robotic arm of the Lightweight Rover Unit 2 (LRU2), allowing the rover to use the instrument autonomously in the field. A compact Nd:YAG laser is utilized for material ablation, generating a micro-plasma that is subsequently analyzed with a small fiber-coupled spectrometer. A single-board computer controls the LIBS hardware components for data acquisition. In this study, we provide details of the ARCHES LIBS instrument implementation, report on preceding laboratory tests where the LRU2 operated the LIBS module for the first time, and showcase the results obtained during the successful ARCHES space analogue demonstration mission campaign in summer 2022 in Sicily. [ABSTRACT FROM AUTHOR]

Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) is a promising candidate for future lithium-ion battery (LIB) electrolytes because of its increased stability and ionic conductivity. One major drawback of this salt, however, is its ability to dissolve Al, leading to a degradation of current collectors in LIBs over time. Surface passivating additives can reduce or even completely suppress the dissolution. A truly cost and material-efficient suppression, however, can only be achieved by identifying the ideal (i.e., minimal) amount of additive. Therefore, quantifying the dissolution-suppressing effect of additives is necessary to create an optimum electrolyte mixture. In this work, we examine the influence of lithium hexafluorophosphate (LiPF6) addition to LiTFSI-based electrolytes via cyclic voltammetry (CV) in an electroanalytical flow cell (EFC) coupled on-line to an inductively coupled plasma mass spectrometer (ICP-MS) for continuous downstream elemental analysis. This setup allows the potential resolved quantification of Al dissolution with unprecedented precision in real-time. With that, we found that already very small amounts of 0.02 M LiPF6 added to 0.98 M LiTFSI will drastically reduce the total dissolved amount of Al during one CV cycle by a factor of ∼ 20, while electrolytes containing 0.30 M LiPF6 (and 0.70 M LiTFSI) completely suppress the dissolution of Al. These findings allow the substitution of large portions of LiPF6, enabling the production of safer LIBs without risking current collector degradation.

Catalyst improvement for the preferential oxidation of CO (CO-PROX) is essential in developing efficient fuel cell technologies. Here, we investigate the promotion of the Cu/CeO 2 system with Pt, prepared by impregnation and alcohol-reduction methods, in the CO-PROX reaction under ideal and realistic feed compositions. The high Pt dispersion in PtCu/CeO 2 prepared by impregnation led to a CO conversion of 62% and CO 2 selectivity of 83% at 50 °C under a feed stream composed of H 2 /CO/O 2 , while monometallic Cu/CeO 2 and Pt/CeO 2 showed negligible activity at these conditions. By adding CO 2 –H 2 O to the feed stream, PtCu/CeO 2 catalysts prepared by both methods presented similar activity. The maximum CO conversion temperature was shifted to 100 °C. Under these conditions, Cu/CeO 2 was inactive, and Pt/CeO 2 showed identical conversion but lower CO 2 selectivity. In-situ XANES revealed that fast oxidation of Cu species at low temperatures is responsible for Cu/CeO 2 deactivation, while preferential adsorption of CO on Pt0 sites in PtCu/CeO 2 avoided deactivation. The use of deactivation-resistant Pt sites as complimentary sites for CO activation associated with improved oxygen mobility over Cu–CeO 2 surface proved to be an effective strategy for CO-PROX under H 2 O/CO 2 feed stream at low temperatures. [Display omitted] • PtCu/CeO 2 prepared by impregnation and alcohol-reduction was applied in CO-PROX. • PtCu/CeO 2 showed higher CO conversion than Cu/CeO 2 at low temperatures (<120 °C). • Pt/CeO 2 showed similar conversion to PtCu/CeO 2 but lower CO 2 selectivity. • XANES revealed deactivation by fast oxidation of Cu at low temperature over Cu/CeO 2. • Preferential adsorption of CO on Pt0 avoided deactivation under the CO 2 –H 2 O stream. [ABSTRACT FROM AUTHOR]

Na-ion batteries (NIBs) with ionic liquid (IL) electrolytes are promising candidates for large-scale energy storage devices owing to the abundance of Na resources and the safety of ILs. In our previous study, we have demonstrated the improved rate capability of NIBs consisting of a hard carbon negative electrode, an NaCrO2 positive electrode, and an FSA-based IL electrolyte (FSA = bis(fluorosulfonyl)amide) by increasing the Na+ ion concentration in the IL. However, this phenomenon is not consistent with the trend observed for the ionic conductivities of bulk ILs. In this study, to clarify the unexplained behavior particularly for electrolytes with high Na+ concentrations, we performed in-situ Raman spectroscopic analysis in the vicinity of the electrode/electrolyte interface. The results of discharge rate capability tests indicated that a rate-determining step existed in the reaction at the positive electrode, where Na+ insertion occurred during discharge. In-situ Raman spectroscopy for Na/NaCrO2 half-cells using an IL electrolyte of low Na+ concentration (∼1 mol dm−3) revealed that the Na+ ion concentration at the interface (inside the NaCrO2 composite electrode) locally decreased as the discharging proceeded. In contrast, a high Na+ concentration electrolyte (∼2.2 mol dm−3) considerably suppressed the decrease in the Na+ ion concentration at the interface. Therefore, the improved performance of the electrolyte with a high Na+ concentration can be explained by the local Na+ ion concentration near the electrode/electrolyte interface, rather than by the bulk properties of the IL electrolytes.

The legacy of the early days of the Atomic Age consists of many problematic sites worldwide, including radioactive waste dumps, uranium mines, spent fuel reprocessing plants, and defunct processing and enrichment plants. Although nature quickly reclaims abandoned sites, any remaining radioisotopes can pose a threat for millennia to come, long after the benefits gained from nuclear technology have faded. The field of nuclear industrial archaeology specialises in finding and characterising these sites to support local communities and site owners. Where maps and building plans have been lost, nuclear archaeologists deploy state-of-the-art analysis techniques on the ground to unravel the current state of legacy sites, and quantify the remaining radioactive inventories to the standard required by the nation the site is located within. The objectives of nuclear industrial archaeology are varied and site dependent. Whether the objective is to puzzle the forgotten history of activity back together or safeguard and recover dangerous radioactive materials, nuclear industrial archaeology adapts radioanalytical laboratory and site-surveying techniques in order to understand the site and allow scientists to communicate this information to support remediation efforts. This paper discusses current methodologies alongside a case study. [ABSTRACT FROM AUTHOR]

To address the need for high-quality in-field repair of composite structures, a vacuum-bag-only (VBO) prepreg was designed, produced, and evaluated. The prepreg featured semi-preg formatting and a room-temperature-stable resin. The format provided a multitude of pathways with much shorter breathe-out distances relative to conventional, edge-breathing VBO prepregs, and thus enhanced through-thickness air permeability. A custom-built scarfed repair tool with an in-situ observation window was designed and employed to analyze the cure process during a repair. Microstructural quality, interlaminar shear strength, and glass transition temperature of semi-preg panels were compared to wet-laid epoxy panels processed with double vacuum debulking (DVD). The semi-preg formatting effectively reduced porosity for in-field scarf panels, and when used with the new material system, presents a viable alternative to DVD and wet layup.

In the framework of the Helmholtz ARCHES project, a multitude of robots, including rovers and drones, were prepared for the autonomous exploration of a test site at the foothills of Mt. Etna, Sicily—a terrain resembling extraterrestrial locations such as the Moon. To expand the suite of tools and sensors available for the exploration and investigation of the test site, we developed a laser-induced breakdown spectroscopy (LIBS) instrument for the geochemical analysis of local geological samples. In alignment with the mission scenario, this instrument is housed in a modular payload box that can be attached to the robotic arm of the Lightweight Rover Unit 2 (LRU2), allowing the rover to use the instrument autonomously in the field. A compact Nd:YAG laser is utilized for material ablation, generating a micro-plasma that is subsequently analyzed with a small fiber-coupled spectrometer. A single-board computer controls the LIBS hardware components for data acquisition. In this study, we provide details of the ARCHES LIBS instrument implementation, report on preceding laboratory tests where the LRU2 operated the LIBS module for the first time, and showcase the results obtained during the successful ARCHES space analogue demonstration mission campaign in summer 2022 in Sicily.

The study of photochemical reactions is of great importance in many fields including the pharmaceutical, food, and paint industry. Most of these photochemical processes are being studied to better understand how to apply them for a specific purpose or how unwanted effects can be prevented. Advances are still being made in photoreactor design, where in-situ detection of the involved reagents and products is an important development. Liquid-core waveguides (LCWs) allow simultaneous illumination and optical assessment of liquid samples and, therefore, constitute one way of combining photoreactor design with on-line or in-situ analytical detection methods. LCWs possess several interesting characteristics, such as low light loss, increased optical path length, and possibilities for coupling with spectroscopic techniques. The current review discusses the state-of-the-art of LCWs applied as photoreactors, for analytical detection, and their combinations. We discuss the differences between several total internal reflection (TIR)-based LCWs, including polymer and polymer-coated capillaries, and silica aerogels, and interference-based waveguides, including Bragg fibers, holey fibers, Kagomé fibers and anti-resonance reflecting optical waveguides (ARROWs). Assessed characteristics include the (freedom of) design, the degree of light attenuation, the range of transmittable wavelengths, gas permeability, compatibility with analytical techniques, current challenges, and applications.

This study presents a non-invasive in situ methodology based on the use of portable elemental (energy dispersive X-ray fluorescence spectroscopy, EDXRF) and molecular (Raman spectroscopy) spectroscopic-based instrumentation as a tool to obtain preliminary information to assist subsequent provenance studies of archaeological cinnabar pigments in the laboratory. In this work, six cinnabar mineral ores, extracted from the Almadén mining district and an original raw pigment coming from the Archaeological Park of Pompeii have been analyzed. As the detection capacities and spectral resolution of the portable instruments are usually poorer than the equivalent benchtop equipment, a comparative study of the in-situ and laboratory results was conducted. Afterward, chemometric data treatment was performed considering both the molecular and elemental information. According to the elemental results, it was not possible to find a strong concordance between the cinnabar ores and the pigment from Pompeii, suggesting the need for additional methodologies in the laboratory (isotope ratio analysis) to complete a proper provenance study. However, this approach was useful to classify the ores according to their mineralogical differences. Therefore, this methodology could be proposed as a useful tool to conduct a representative sampling of the cinnabar mineral ores to be considered in a provenance study of archaeological cinnabar pigments. [ABSTRACT FROM AUTHOR]

Since their introduction in the early decades of the 20th century, fluorescent pigments have found progressively wider applications in several fields. Their chemical composition has been optimized to obtain the best physical properties, but is not usually disclosed by the manufacturers. Even the other class of luminescent pigments, namely the phosphorescent ones, is now produced industrially. The peculiar optical properties of these pigments have attracted more and more the attention of famous artists since the middle of the last century. The Italian Black Light Art movement exploits the possibility of conveying different aesthetical messages depending on the kind of radiation (UV or visible) with which the artwork is illuminated. In the present work, a non-invasive in-situ investigation based on Raman, fluorescence, and visible-reflectance spectroscopies was performed on a series of Black Light Art paintings exhibited in Milan (Italy) in 2017, succeeding in the identification of the materials used by the artists. In particular, the use of both fluorescent and phosphorescent pigments, alone or combined with conventional synthetic organic pigments, has been recognized. [ABSTRACT FROM AUTHOR]

The carbon interlayers in the multilayer coatings can improve the load-bearing capacity and oxidation resistance, promote the layer-by-layer wear mechanism, and extend the lifespan of the multilayer coating, which is crucial to improving their tribological properties. To investigate the role of C interlayers in the competitive relationship between tribochemistry and material removal in multilayer coatings, this study comprehensively examines the tribological behavior of single layer MoS 2 and multilayer MoS 2 /C coatings through in-situ tribotests and nanoscratch tests. Key findings reveal that the C interlayers enhance the tribological behavior by reducing the oxidation rate of MoS 2 , improving the load distribution, and delaying the onset of coating failure. Specifically, the single layer MoS 2 coating demonstrated a lifespan of 55,000 cycles, whereas the multilayer MoS 2 /C coating achieved 80,000 cycles, reflecting a 45 % enhancement. The critical load increased from 8 mN to 18 mN, indicating a 125 % improvement in removal resistance. The presence of C layers results in a more stable and enduring tribofilm, which leads to reduced friction and wear. This study underscores the importance of in-situ analysis by combining nanoscratch with Raman mapping to elucidate the complex tribological behavior of coatings. These insights are crucial for designing efficient, wear-resistant, low-friction multilayer coatings for diverse industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Electrochemical CO 2 reduction (eCO 2 R) has emerged as a promising avenue, offering the dual benefits of mitigating atmospheric CO 2 while generating value-added chemicals and fuels. In particular, eCO 2 R to methanol (CH 3 OH) holds significant promise due to its various applications in energy and chemical industries, yet only a few studies have been reported thus far, primarily due to the complexity of its reaction pathway. This review first focuses on elucidating the intricate reaction mechanisms involved in CH 3 OH production via eCO 2 R. Then, we highlight recent advancements in catalyst designs, including Cu-based, non-Cu-based, and CoPc-based electrocatalysts. Finally, we summarize the in-situ analysis techniques, including vibrational spectroscopy, X-ray absorption spectroscopy, and differential electrochemical mass spectrometry, which help gain an in-depth understanding of the reaction intermediate, surface/electronic/geometric structures of electrocatalysts under the working environments. By providing a comprehensive overview of eCO 2 R pathways towards CH 3 OH and introducing rational design principles for electrocatalysts, we believe this review can significantly contribute to the advancement of efficient and selective CH 3 OH production and offer valuable insights into the field. [Display omitted] • The recent progress in electrochemical CO 2 reduction for methanol production is summarized. • This review offers an overview of the well-established pathway for methanol electrosynthesis from CO 2. • Novel catalyst designs for enhanced methanol selectivity are explored. • Valuable information from various in situ analysis techniques are investigated. • This review provides a novel perspective on the future direction of the electrochemical methanol synthesis. [ABSTRACT FROM AUTHOR]

• The cobalt mineralization was dated to ∼2100 Ma based on Re-Os isochron ages of cobalt-bearing pyrites. • Cobalt was mainly hosted in carrollite, linnaeite, and pyrite. • The Songjiashan deposit belongs to the sedimentary, metamorphic, and hydrothermal superposition type Co-Fe deposit. The Songjiashan Co-Fe deposit in the central part of the "Tongshan skylight" on the southeastern edge of the Zhongtiao Mountains is hosted by the volcanic-sedimentary rock series of the Paleoproterozoic Songjiashan Group. The spatial distribution of the orebodies is controlled by south-north trending rock units. Based on microscopic observations, the dominant ore minerals included magnetite, pyrite, chalcopyrite, carrollite, and linnaeite, while gangue minerals comprised quartz, calcite, sericite, and chlorite. Cobalt-iron ores had massive, banded, disseminated, and veinlet texture, and alteration of the host rocks included silicification, sericitization, pyritization, carbonation, and chloritization. Mineralization processes of the Songjiashan deposit were grouped into three periods: sedimentation, metamorphism, and hydrothermal. The Co concentrations in hydrothermal pyrite (Py-III) varied from 1.05 % to 3.75 %, with an average of 2.45 %. Cobalt in pyrite was homogeneously distributed and inversely correlated to Fe, indicating that Co isomorphically replaced Fe in pyrite. The characteristic Co/Ni ratio of pyrite varied greatly, ranging from 0.1 to 1000, reflecting various genetic types of sedimentation, metamorphism, and hydrothermal mineralization, with the main mineralization period primarily related to hydrothermal activities. Zircon U-Pb geochronology of the host rock and Re-Os isochron of Co-bearing pyrites indicate that Co mineralization mainly occurred at ∼2100 Ma. In-situ S isotopic analysis of sulfides reveals two peak δ34S values of 5–9 ‰ and 12–16 ‰. We interpret that the former value reflects the mixing of volcanic and marine sulfate sources, while the latter value is mainly artributted to marine sulfate sources. All δ34S values were lower than those of Proterozoic marine sulfates (15–20 ‰). Accordingly, we infer that thermochemical sulfate reduction plays a key role in marine sulfate reduction, and that the formation of Co-rich ore bodies in the Songjiashan deposit have undergone processes of initial sedimentation, metamorphism-deformation, and subsequent hydrothermal overprinting. Genetically, we suggest that the Songjiashan deposit belongs to a sedimentary-metamorphic hydrothermal superposition type Co-Fe deposit. [ABSTRACT FROM AUTHOR]

To address the need for high-quality in-field repair of composite structures, a vacuum-bag-only (VBO) prepreg was designed, produced, and evaluated. The prepreg featured semi-preg formatting and a room-temperature-stable resin. The format provided a multitude of pathways with much shorter breathe-out distances relative to conventional, edge-breathing VBO prepregs, and thus enhanced through-thickness air permeability. A custom-built scarfed repair tool with an in-situ observation window was designed and employed to analyze the cure process during a repair. Microstructural quality, interlaminar shear strength, and glass transition temperature of semi-preg panels were compared to wet-laid epoxy panels processed with double vacuum debulking (DVD). The semi-preg formatting effectively reduced porosity for in-field scarf panels, and when used with the new material system, presents a viable alternative to DVD and wet layup. [ABSTRACT FROM AUTHOR]

The thermoelastic effect indicates the dependency of temperature and volume change in the material and, due to the heat released during plastic deformation, a temperature minimum occurs in the region of the onset of yielding. An experimental setup is presented for the microscopic analysis of the thermoelastic effect, which allows high precision measurements of specimen. In-situ diffraction experiments were performed for a single phase low carbon steel HC260Y using synchrotron diffraction at the High Energy Material Science beamline P07 in Petra III, DESY. This allows a direct comparison of the onset of yielding by observing the evolution of lattice strains and dislocations densities with the specimen temperature in a continuous cyclic test having high measuring frequency and accuracy. Therefore, the lattice strains are evaluated based on the peak shift of several lattice planes and the dislocation density is estimated based on the micro strain due to peak broadening. The results prove existing assumptions about the relation between the thermoelastic effect and the onset of yielding and clearly qualify the temperature-based determination method for material characterization on a microstructural basis. The usefulness of the temperature elasticity parameters is shown exemplarily with the determination of loading moduli and compared to existing methods.

Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method is characterized by in-situ, high space resolution and high sensitivity. Therefore, the study of LA-ICP-MS in-situ trace elements analysis in magnetite has made a rapid progress and it is widely used in geological field in recent years. An analytical method for the trace elements determination of magnetite by LA-ICP-MS using Agilent 7700X inductively coupled plasma-mass spectrometry (ICP-MS) and Photo Machines Analyte Excite 193nm laser ablation was established at the laboratory of mineralization and dynamics, Chang′an University. This method adopts multiple external standards (BIR-1G, BHVO-2G, BCR-2G and GSE-1G) as calibration standards without an internal standard. Trace element compositions of the glass standard material NIST 612 and natural magmatic magnetite BC 28 were determined by the established method to evaluate its reliability. The results show that the relative standard deviation (RSD, N=30) of trace elements in NIST 612 ranges from 1.31% to 6.33%. Compared with the recommended values and the previous reference values obtained by LA-ICP-MS, the relative error of most elements in NIST 612 is smaller than 10%. The RSD (N=30) of most elements in BC 28 is lower than 10%, and the relative error of 11 important trace elements in BC 28 is smaller than 10% compared with the reported values by LA-ICP-MS. The above results show that in-situ trace element determination of magnetite can be carried out by using the method established in this study. The analysis data is accurate and reliable, and it has a great application potential.

This study presents a non-invasive in situ methodology based on the use of portable elemental (energy dispersive X-ray fluorescence spectroscopy, EDXRF) and molecular (Raman spectroscopy) spectroscopic-based instrumentation as a tool to obtain preliminary information to assist subsequent provenance studies of archaeological cinnabar pigments in the laboratory. In this work, six cinnabar mineral ores, extracted from the Almadén mining district and an original raw pigment coming from the Archaeological Park of Pompeii have been analyzed. As the detection capacities and spectral resolution of the portable instruments are usually poorer than the equivalent benchtop equipment, a comparative study of the in-situ and laboratory results was conducted. Afterward, chemometric data treatment was performed considering both the molecular and elemental information. According to the elemental results, it was not possible to find a strong concordance between the cinnabar ores and the pigment from Pompeii, suggesting the need for additional methodologies in the laboratory (isotope ratio analysis) to complete a proper provenance study. However, this approach was useful to classify the ores according to their mineralogical differences. Therefore, this methodology could be proposed as a useful tool to conduct a representative sampling of the cinnabar mineral ores to be considered in a provenance study of archaeological cinnabar pigments.

The complex reaction mechanism of iron-based Fischer-Tropsch synthesis comprises of manifold primary and secondary reaction pathways. Within this work, an experimental setup for spatially-resolved measurements on promoted iron-based Fischer-Tropsch catalysts is presented, allowing for a general study of the influence of operating conditions and promotion as well as of the influence of secondary reactions on product selectivity. It was found that, depending on catalyst composition, considerable hydrogenation of 1-alcohols and olefins occurs, while no considerable influence of reinitiation of chain growth on product distribution could be found.

[Display omitted] • The development of a global prediction model for in-situ analysis in Rehmanniae Radix using near-infrared spectrometers. • An analysis was conducted to evaluate the qualitative and quantitative models for different portable near-infrared spectrometers (DLP NIRscan Nano and VIAVI MicroNIR 1700). • The study employed a transfer method based on Improved Principal Component Analysis (IPCA), which converted spectra from different types of NIR spectrometers with different data points or absorbance. As a Chinese herbal medicine with high medical value, Rehmanniae Radix (RR) has a wide variety of geographical origins leading to distinctly diverse quality, and moisture content during storage affects the critical active ingredient content. In this work, two portable near-infrared (NIR) spectrometers, DLP NIRscan Nano (DLP) and VIAVI MicroNIR 1700 (M1700) were used for in-situ spectral acquisition from intact RR. The partial least squares-discriminant analysis (PLS-DA) was employed for three geographical sources (Shandong, Shanxi, Henan). After multiple pre-processing and wavelength selection, the M1700-based PLS-DA model, accuracy (Acc), sensitivity (Sen), and specificity (Spe), achieved 100 % accuracy. In contrast, model predictions using the low-cost instrument (DLP) was not satisfactory. The partial least squares regression (PLSR) was applied to predict the moisture content of RR. The best correlation coefficients in the prediction set (R2 p), Root Mean Square Error of Prediction (RMSEP), and residual prediction deviation (RPD) values (0.98, 0.98, 4.98) were obtained by DLP and were also employed for comparison with the M1700 model (0.99, 0.70, 7.00). Therefore, to further improve the model prediction effect of the low-cost DLP, we employed the improved principal component analysis (IPCA), direct standardization (DS), and piecewise direct standardization (PDS) calibration transfer techniques. Unequivocally, IPCA optimized the origin identification model (Acc, Sen, and Spe were all 1.00), the moisture content prediction model RPD was increased by 23 %, and its RMSEP was reduced by 18 %, leading to the improvement in prediction accuracy of the DLP model. This study provides a portable and low-cost detection method for the in-situ evaluation of the quality of RR quality and a feasible solution for the NIR techniques to be used in the rapid and accurate in-situ analysis of RR. [ABSTRACT FROM AUTHOR]

[Display omitted] • REE mineralization in the Lala deposit primarily formed at ca. 850 Ma. • The host rocks and contemporaneous felsic magmatic rocks serve as the primary sources of REE metallogenic materials. • Na, CO 2 , and F-rich magmatic waters aid REE mineralization, mixing with meteoric waters, leaching the REE from host rocks and early ores. The Lala deposit in the Kangdian metallogenic province is one of the most important iron oxide copper–gold (IOCG) deposits in South China. Rare earth element (REE) activation, migration, and redistribution occurred during late-stage Cu mineralization in the deposit. However, the geological characteristics of REE mineralization and the genetic mechanism of this deposit remain poorly understood. The goal of this study was to investigate REE mineralization and the ore-forming process in the Lala deposit by employing a comprehensive approach that included techniques in petrography, mineralogy, and geochemistry. Mineralogical analysis indicated that the REE-bearing minerals in this deposit include bastnäsite, monazite, parisite, xenotime, apatite, and fluorite. Apatite was observed to have high concentrations of REE (ΣREE ranging from 7,409 to 18,739 ppm). The results of U-Pb isotope dating of bastnäsite and xenotime suggest that the REE mineralization in the Lala deposit primarily formed at ca. 850 Ma, aligning with the Neoproterozoic magmatism in this region. The chondrite-normalized REE pattern of apatite is similar to that of host rocks and contemporaneous magmatic rocks; the ε Nd(t) values of bastnäsite and xenotime (calculated at ca. 850 Ma) ranged from −12.2 to −7.0, which is comparable to the values obtained for contemporaneous country rock (−8.7 to −6.4) and felsic intrusive rocks (−9.6 to 4.4). This similarity indicates that the host rocks and contemporaneous felsic magmatic rocks serve as the primary sources of REE metallogenic materials. The ∼ 850 Ma REE mineralization overprints the early stage Fe-Cu mineralization and is associated with a Neoproterozoic magmatic event. During this process, Na, CO 2 , and F-rich magmatic water mixes with meteoric water and leaches REE from host rocks and early-stage ores. Under the disintegration of REEs, F-complex in hydrothermal fluids, REE minerals (e.g., monazite, bastnäsite, parisite, and xenotime) precipitate together with apatite and fluorite in the Fe-Cu ores. [ABSTRACT FROM AUTHOR]

Simultaneous ultraviolet and thermal treatments (SUTs) enhanced the stability of tungsten-doped indium zinc oxide (W-IZO) thin-film transistor (TFT) compared to the furnace-annealed W-IZO TFT. To understand the change in electrical device instability, we used the in-situ measurement under the gate bias stress to investigate the electronic structure of active layer in actual TFT device. The physical properties of the active layer in the actual TFT structure, such as the unoccupied states in the conduction band and the band edge states below the conduction band, are related to the defect states of the oxide material and show the behavior of charge trapping. Improvement of the device stability mainly comes about from dynamic changes in the electron trap site in the channel region. The in-situ analysis, the relative conduction band area, and the band edge states for SUT-treated W-IZO active layer are much less changed under the gate bias stress than the furnace annealed W-IZO active layer. [ABSTRACT FROM AUTHOR]