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20 pages, 36524 KB  
Article
Fluid Evolution of the Dajing Cu-Sn Polymetallic Deposit, Southern Great Xing’an Range: Constraints from Quartz Textures and Trace Elements
by Yanping He, Zhenjun Sun, Henan Yu, Yunsheng Ren, Zhenzhen Li, Mengfan Guan and Zhiwen Zheng
Minerals 2026, 16(9), 867; https://doi.org/10.3390/min16090867 - 25 Aug 2026
Viewed by 203
Abstract
The Dajing Cu-Sn polymetallic deposit, situated within the southern Great Xing’an Range of northern China, is a representative Mesozoic magmatic–hydrothermal system within a major Cu–Sn–Ag–Pb–Zn metallogenic belt. Located at the junction between the Siberian and North China plates, the deposit occurs within a [...] Read more.
The Dajing Cu-Sn polymetallic deposit, situated within the southern Great Xing’an Range of northern China, is a representative Mesozoic magmatic–hydrothermal system within a major Cu–Sn–Ag–Pb–Zn metallogenic belt. Located at the junction between the Siberian and North China plates, the deposit occurs within a composite tectonic domain overprinted by the Paleo-Asian, Mongol–Okhotsk, and Paleo-Pacific systems. Building on field geological constraints and detailed ore petrography, this study utilizes SEM–CL imaging and in situ LA–ICP–MS trace-element analysis of hydrothermal quartz to reconstruct the multistage physicochemical evolution and fluid dynamics of the ore-forming system. Three quartz generations record successive mineralization stages: early QI forms grain cores associated with Stage I cassiterite–arsenopyrite–quartz mineralization; main-stage QII crystallized during or shortly after Stage II chalcopyrite precipitation and exhibits well-developed oscillatory zoning; and late QIII occurs mainly as rim overgrowths and fracture fillings and postdates Stage III ore-mineral precipitation. Quartz is characteristically Ti-poor (4.7–22.8 ppm), and its trace-element systematics indicate a low- to intermediate-temperature hydrothermal signature and a granitic magmatic–hydrothermal affinity. Al, Li, Na, K, and Ge show coupled behavior consistent with heterovalent substitution and vary markedly among quartz generations, with CL-bright QIIa showing relatively higher Al, Ge, and Na relative to CL-dark QIIb, whereas QIII is generally characterized by lower Al, Li, and Ge. Localized anomalously high Cu and Sn values are mainly attributed to the co-ablation of fine-grained mineral inclusions, metal-rich fluid inclusions, or fracture-filling components. These features indicate a chemically heterogeneous fluid reservoir with inferred relatively acidic conditions during the initial Sn-mineralization stage. The fluid system subsequently experienced recurrent physicochemical fluctuations associated with pulsed fluid input during the principal Cu-mineralization stage. QIII records a trace element-depleted late-fluid system associated with the terminal pyrite–quartz stage. Late fluids migrated along earlier quartz boundaries and fractures and may have undergone further cooling and dilution through fluid mixing and/or water–rock interaction. Overall, the fluid system shows a progressive shift in inferred fluid chemistry, consistent with decreasing acidity during hydrothermal evolution. Full article
(This article belongs to the Section Mineral Deposits)
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16 pages, 8776 KB  
Article
Technical Feasibility of Custom-Fabricated Auxetic Foam Insoles for Plantar Pressure Redistribution: An Exploratory Pilot and Bootstrap Resampling Investigation
by LaBreesha Batey, Enrique M. Jackson, Changchun Zeng and Selvum Pillay
Materials 2026, 19(16), 3446; https://doi.org/10.3390/ma19163446 - 14 Aug 2026
Viewed by 262
Abstract
Peripheral neuropathy degrades gait mechanics, elevating peak plantar pressures (PPP) and tissue ulceration risks. This exploratory pilot study evaluates custom orthotics using thermo-mechanically synthesized re-entrant auxetic foam insoles with targeted dome-shaped inserts. Bilateral dynamic gait analysis was conducted across a heterogeneous cohort ( [...] Read more.
Peripheral neuropathy degrades gait mechanics, elevating peak plantar pressures (PPP) and tissue ulceration risks. This exploratory pilot study evaluates custom orthotics using thermo-mechanically synthesized re-entrant auxetic foam insoles with targeted dome-shaped inserts. Bilateral dynamic gait analysis was conducted across a heterogeneous cohort (N = 9) utilizing a P-Walk 600 pressure plate and a MARVUE 2D motion capture system inside standardized footwear. To address small-sample limits, a non-parametric bootstrap resampling analysis (B = 1000) was executed. Native auxetic foam demonstrated high internal consistency ((σ*) = 12.063 kPa, Consistency Rank = 1), showing a strong numerical propensity to restrict load distribution variability compared to factory-installed over-the-counter (OTC) memory foam controls. While initial cell-adaptation cycles were observed, custom insoles reduced PPP by up to 62.2% in systemic polyneuropathies, shifting signatures beneath the exploratory clinical safety target (<200 kPa) in 55% of simulated cases. Conversely, customization triggered an adverse volumetric crowding effect in focal mononeuropathies, suggesting un-customized native auxetic foam as the preferred structural configuration for this specific cohort to avoid premature cell densification. Re-entrant cellular structures accommodate heterogeneous pathomechanics, offering an exploratory pathway for patient-specific orthotic optimization. Full article
(This article belongs to the Special Issue Advances in Auxetic Materials)
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35 pages, 6760 KB  
Review
Solvent Interaction Analysis: A New Lens for Protein Structure and Diagnostics
by Boris Y. Zaslavsky, Mark Stovsky and Vladimir N. Uversky
Int. J. Mol. Sci. 2026, 27(15), 6645; https://doi.org/10.3390/ijms27156645 - 25 Jul 2026
Viewed by 284
Abstract
Aqueous two-phase systems (ATPSs) provide a versatile, fully aqueous platform for probing solute–water interactions and protein structure. This review first surveys the diversity and phase behavior of biphasic aqueous systems formed by polymers and salts. We describe how phase diagrams characterize ATPS formation [...] Read more.
Aqueous two-phase systems (ATPSs) provide a versatile, fully aqueous platform for probing solute–water interactions and protein structure. This review first surveys the diversity and phase behavior of biphasic aqueous systems formed by polymers and salts. We describe how phase diagrams characterize ATPS formation and composition and how both polymer chemistry and salt identity, rather than molecular size alone, govern phase separation by modulating the solvent properties of water. Building on a modified binodal model, we show that phase separation and solute partitioning can be understood in terms of changes in aqueous solvent dipolarity/polarizability, hydrogen-bond donor/acceptor properties, hydrophobicity, and electrostatics, quantified via solvatochromic probes and homologous solute series. These measurements underpin solvent interaction analysis (SIA), in which the partition coefficients of small molecules and proteins across panels of ATPSs are used to generate “structural signatures” that sensitively report on amino acid substitutions, conformational changes, aggregation, ligand binding, osmolyte effects, and post-translational modifications, independent of protein size. We discuss how SIA can be implemented in vial-, plate-, and microfluidic formats and combined with diverse analytical readouts (HPLC, MS, colorimetric assays, and immunoassays), and we contrast this structure-focused approach with conventional concentration-only proteomic and biomarker strategies. Particular emphasis is placed on structure-based biomarker discovery, where disease-relevant shifts in proteoform distributions—especially glycosylation changes—are often more informative than bulk protein levels and where SIA can complement or simplify complex glycomics and top-down proteomics workflows. As a case study, we describe the recently FDA-approved IsoPSA assay, which applies SIA principles to prostate-specific antigen by measuring cancer-associated structural alterations in circulating PSA via its partition behavior in a proprietary ATPS. IsoPSA generates a single index that discriminates between high-grade prostate cancer and benign and low-grade conditions. Prospective, longitudinal, and MRI-integrated clinical studies demonstrate that IsoPSA improves pre-biopsy risk stratification, reduces unnecessary biopsies, and provides robust negative and positive predictive values within the PSA “gray zone.” Collectively, the data support aqueous solvent interaction analysis as a broadly applicable, mechanistically grounded technology for protein characterization, drug–protein interaction studies, and structure-centric biomarker development, exemplified by the clinical translation of IsoPSA. Full article
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17 pages, 6533 KB  
Article
Mechanical and Spectrophotometric Properties of Nano-WS2 Modified PVB/Epoxy Coatings on Glass
by Danica M. Bajić, Aleksandra Samolov, Bojana Fidanovski, Miloš Pavić and Ana Alil
Coatings 2026, 16(7), 846; https://doi.org/10.3390/coatings16070846 - 16 Jul 2026
Viewed by 412
Abstract
The development of transparent multifunctional coatings capable of combining optical properties with mechanical durability remains a significant challenge in advanced materials engineering. In this study, novel hybrid coatings based on a poly(vinyl butyral)/epoxy resin (PVB/epoxy) matrix reinforced with tungsten disulfide (WS2) [...] Read more.
The development of transparent multifunctional coatings capable of combining optical properties with mechanical durability remains a significant challenge in advanced materials engineering. In this study, novel hybrid coatings based on a poly(vinyl butyral)/epoxy resin (PVB/epoxy) matrix reinforced with tungsten disulfide (WS2) nanostructures were developed and examined for potential application in camouflage protection of glass surfaces. Camouflage aims to reduce the detectability of an object by minimizing the optical contrast between the object and its surrounding environment. For transparent substrates such as glass, this objective is particularly demanding because the transparency must be preserved while reducing unwanted surface reflection and optical signatures over relevant spectral ranges. For this purpose, in this research two types of nanostructures were investigated: fullerene-like nanoparticles (IF-WS2) and inorganic nanotubes (INT-WS2). The coatings were fabricated via ultrasonically assisted solution dispersion followed by casting over the glass plates and Teflon molds, and solvent evaporation. Structural, thermal, optical, and mechanical properties were systematically evaluated using SEM, FTIR, DSC, UV-Vis-NIR spectroscopy, gloss measurements, hardness testing, and cavitation wear resistance analysis. The incorporation of WS2 nanostructures led to improved mechanical performance, with increased hardness and enhanced resistance to cavitation-induced wear. Optical characterization showed moderate reductions in reflectance and controlled transmittance in the visible and near-infrared regions, while overall transparency was maintained. The results indicate that WS2 nanostructures contribute to both light scattering and absorption, leading to reduced specular reflection and improved optical masking potential. The findings demonstrate that hybrid PVB/epoxy/WS2 coatings offer a promising approach for designing transparent, mechanically resistant coatings with tunable optical properties, with potential applications in protective glass systems and advanced functional surfaces. Full article
(This article belongs to the Special Issue Ceramic–Polymer Hybrid Coatings: Multifunctional Solutions)
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20 pages, 6233 KB  
Article
Geological Significance of the Kekedieba Ophiolitic Melange in Taxkorgan, West Kunlun: Evidence from Trace Elements and Isotopes
by Junsheng Zhong, Chengguang He, Dongzhuang Hou, Xinrui Zhang and Li Bai
Minerals 2026, 16(7), 677; https://doi.org/10.3390/min16070677 - 27 Jun 2026
Viewed by 394
Abstract
Ophiolites are fragments of ancient oceanic lithosphere, serving as geological indicators for reconstructing ocean-continent transitions, plate convergence and paleo-ocean evolution in orogenic belts. The Kekedieba ophiolite was recently identified during a 1:50,000 regional geological survey. To constrain its formation age, material source and [...] Read more.
Ophiolites are fragments of ancient oceanic lithosphere, serving as geological indicators for reconstructing ocean-continent transitions, plate convergence and paleo-ocean evolution in orogenic belts. The Kekedieba ophiolite was recently identified during a 1:50,000 regional geological survey. To constrain its formation age, material source and tectonic setting, this study conducted systematic petrological observations, geochemical testing and zircon U-Pb geochronological analyses on the ophiolite. This ophiolite consists of typical end-members, such as cumulate gabbro and diabase dykes. Trace element analyses and geochemical discrimination diagrams reveal that the basalts exhibit geochemical characteristics typical of mid-ocean ridge basalt (MORB), and the ophiolite suite as a whole belongs to the low-K tholeiite series. Differences in the degree of partial melting in the source region among various end-member rocks further indicate the complexity of its tectonic setting. LA-ICP-MS zircon U-Pb dating shows that the formation age of the gabbro is 321.4 ± 2.7 Ma, indicating that the Kekedieba ophiolite formed in the late Early Carboniferous. Combined with its tectonic slice-association relationship with Early Carboniferous island-arc volcanic rocks, it is identified as fragments of a SSZ-type supra-subduction zone ophiolite, which provides direct evidence for the subduction evolution of regional paleo-plates. Although some extrusive units retain MORB-like geochemical signatures inherited from early seafloor spreading, the island-arc affinities of the full lithological suite and subduction imprints in cumulates confirm a dominant SSZ origin. Full article
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19 pages, 4250 KB  
Article
Impact of Parent Material on the Chemodiversity and Vertical Dynamics of Dissolved Organic Matter in Paddy Soils
by Yiming Cao, Hang Wei, Zhiliang Chen and Huashou Li
Agronomy 2026, 16(11), 1092; https://doi.org/10.3390/agronomy16111092 - 31 May 2026
Viewed by 365
Abstract
Parent material is a fundamental determinant of soil pedogenesis, yet its specific role in regulating the molecular composition and vertical evolution of dissolved organic matter (DOM) in paddy soils remains poorly understood. The primary objective of this study was to elucidate how distinct [...] Read more.
Parent material is a fundamental determinant of soil pedogenesis, yet its specific role in regulating the molecular composition and vertical evolution of dissolved organic matter (DOM) in paddy soils remains poorly understood. The primary objective of this study was to elucidate how distinct parent materials and soil depths interact to shape DOM chemodiversity. This study investigated 14 paddy soil samples from the plow horizon (Ap, 0–20 cm) and subsoil horizon (Br, 20–50 cm) paddy soils derived from seven parent materials (plate shale: PS, quaternary red clay: QRC, granite: GR, Alluvial Sediment: AS, limestone: LS, sandy gravel: SG, and purple soil: PR). For each composite sample, DOM extraction and subsequent optical characterizations were performed in triplicate (n = 3 analytical replicates). The analysis of soil physicochemical properties was integrated with ultraviolet-visible (UV-Vis) absorption and excitation-emission matrix spectroscopy combined with parallel factor analysis (EEMs-PARAFAC). Our results revealed that parent material significantly dictated the soil chemical microenvironments, with LS, SG, and PR maintaining alkaline profiles, whereas others exhibited distinct surface acidity. Consequently, this microenvironmental heterogeneity profoundly influenced DOM characteristics. While DOM generally shifted towards higher molecular weight and increased aromaticity with depth, its evolutionary trajectory was highly dependent on the parent material. For instance, SG soils preserved a strong autochthonous signature in Ap, whereas GR soils exhibited the highest humification degree. Furthermore, PARAFAC analysis identified a dominant refractory humic-like component (C1 and C2) alongside a highly variable labile protein-like component (C3, 15–40%). Correlation and principal component analyses (PCA) further demonstrated that soil depth and parent material jointly drive DOM evolution, wherein soil organic matter (SOM) abundance showed strong positive associations with total nitrogen (TN), total phosphorus (TP), and available arsenic. These findings underscore that parent material properties are critical variables for understanding soil carbon cycling and managing heavy metal risks in paddy ecosystems. Full article
(This article belongs to the Section Farming Sustainability)
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36 pages, 6905 KB  
Article
Petroleum Geochemistry of Jurassic Source Rocks in the Frontier Kohat Basin, Northwest Pakistan: An Oil–Source Rock Correlation Study
by Adil Khan, Muhammad Jamil, Lipeng Yao, Ehsan Ul Haq, Ihsan Ullah, Syed Tallataf Hussain Shah and Imran Khan
Processes 2026, 14(10), 1507; https://doi.org/10.3390/pr14101507 - 7 May 2026
Cited by 2 | Viewed by 631
Abstract
Early Jurassic organic-rich shales deposited in fluvio-deltaic settings serve as important hydrocarbon source rocks, particularly in the highly petroliferous basins of the Middle East. The Lower to Middle Jurassic sedimentary succession of the frontier Kohat Basin, Pakistan, comprises thick sequences of shale, coaly, [...] Read more.
Early Jurassic organic-rich shales deposited in fluvio-deltaic settings serve as important hydrocarbon source rocks, particularly in the highly petroliferous basins of the Middle East. The Lower to Middle Jurassic sedimentary succession of the frontier Kohat Basin, Pakistan, comprises thick sequences of shale, coaly, and carbonate rocks deposited along the northwestern margin of the Indian Plate, adjacent to the eastern Tethys Ocean, and records a crucial paleoenvironmental transition from fluvio-deltaic to shallow marine settings. Despite the economic significance of the Jurassic succession as a potential hydrocarbon source in the Kohat Basin and surrounding regions, their organic geochemical characteristics and role in the regional petroleum system remain poorly understood. This study presents an integrated organic geochemical and carbon isotopic evaluation of Jurassic source rocks using well cuttings and outcrop samples, focusing on organic matter (OM) input, depositional environment, hydrocarbon generation potential, thermal maturity, and oil–source rock correlation. Source rock characterization indicates that the Shinawari and Datta formations possess fair-to-excellent generative potential, whereas the Samana Suk Formation exhibits poor-to-marginal potential. Biomarker and isotopic evidence indicate that the Shinawari Formation is dominated by algal-derived OM, characterized by higher aquatic OM deposited under relatively reducing marine to marginal marine conditions. The relatively more depleted bulk and individual fraction δ13C values for the Shinwari Formation are also consistent with a stronger marine influence. In contrast, the Datta Formation shows mixed OM inputs with a greater terrestrial influence and suggests deposition in more oxic lacustrine to marginal marine settings. The thermal maturity-related parameters for both formations indicate early to peak oil window thermal maturity. The geochemical correlation of Jurassic source rock extracts with Kohat crude oils, based on published data, suggests that the Kohat oils differ significantly, exhibiting stronger terrestrial organic matter signatures, more oxic depositional conditions, and slightly higher maturity, thereby indicating no direct genetic linkage with the Jurassic source rocks. Overall, the Jurassic formations are unlikely to represent the primary source rocks for Kohat oils but may have contributed locally to a multi-source petroleum system. This underscores the need for integrated geochemical investigations combining biomarker and isotopic analyses, supported by broader source rock and crude oil datasets, to resolve uncertainties in oil–source correlations, source contributions, and hydrocarbon migration pathways, thereby better constraining the petroleum system framework. Full article
(This article belongs to the Special Issue Research Progress on Bitumen, Heavy-Oil and Petroleum Chemistry)
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15 pages, 5601 KB  
Article
Putative Self-Organizing Human Corneal Organoids Recapitulate Human Corneal Architecture and Cellular Diversity
by Timothy A. Blenkinsop and Anne Z. Eriksen
Bioengineering 2026, 13(5), 518; https://doi.org/10.3390/bioengineering13050518 - 29 Apr 2026
Cited by 1 | Viewed by 1700
Abstract
Background: Corneal organoids derived from pluripotent stem cells have emerged as powerful tools for studying corneal development, disease modeling, and regenerative medicine applications. While previous protocols have successfully generated corneal tissue structures, there remains a need for three-dimensional models that recapitulate the complex [...] Read more.
Background: Corneal organoids derived from pluripotent stem cells have emerged as powerful tools for studying corneal development, disease modeling, and regenerative medicine applications. While previous protocols have successfully generated corneal tissue structures, there remains a need for three-dimensional models that recapitulate the complex cellular architecture and diversity of native human cornea. Methods: We developed a modified spontaneous three-dimensional corneal organoid model using human embryonic stem cells (hESCs) through an adapted Self-formed Ectoderm Autonomous Multi-zone (SEAM) protocol. hESCs were cultured as spheroids in ultra-low-binding plates under normoxic conditions and differentiated over 7–8 weeks. Organoids were characterized using immunofluorescence staining for corneal-specific markers and single-cell RNA sequencing to assess cellular composition and gene expression patterns. Results: Approximately 20% of organoids developed transparent regions characteristic of corneal tissue by day 30 of differentiation. Immunofluorescence analysis revealed spatially organized expression of corneal markers, including ZO-1 and E-cadherin in the outermost epithelial layers, P63α-positive putative limbal stem cells at the epithelial–stromal interface, vimentin-positive stromal cells in the interior, and laminin-1 deposition that suggests Bowman’s membrane formation. The organoids expressed cornea-specific keratins (K3, K12, and K15) and the master regulator PAX6 in appropriate cellular compartments. Single-cell RNA sequencing identified 18 distinct cell clusters, including three corneal epithelium subclusters with differential expression of MUC16, KRT12, and ΔNp63α, two stromal populations with distinct inflammatory profiles, and a corneal endothelium cluster. Transcriptomic analysis confirmed expression of key corneal genes, including AQP3, CDH1, multiple keratins, mucins, and extracellular matrix components (HAS2, CD34, CD44, COL8A1, and KERA). Conclusions: This three-dimensional spheroid-based putative corneal organoid model successfully recapitulates the multilayered architecture and cellular diversity of human cornea, including stratified epithelium, putative limbal stem cells, stroma, and endothelium in spatially appropriate arrangements. The model demonstrates molecular signatures consistent with native corneal tissue and provides a valuable platform for studying corneal development, disease mechanisms, and potential therapeutic applications. Future optimization to improve organoid formation efficiency and functional maturation will enhance the utility of this system for both basic research and translational medicine. Full article
(This article belongs to the Special Issue Bioengineering and the Eye—3rd Edition)
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29 pages, 11787 KB  
Article
Zircon Trace Element Constraints on the Evolution of the Continental Crust in the Western Domain of the Congo Craton
by Ngong Divine Njinchuki, Evine Laure Njiosseu Tanko, Philomène Nga Essomba Tsoungui, Brice Woguia Kamguia, Marvine Nzepang Tankwa, Landry Soh Tamehe, Donald Hermann Fossi and Jean Paul Nzenti
Minerals 2026, 16(4), 414; https://doi.org/10.3390/min16040414 - 16 Apr 2026
Viewed by 995
Abstract
This study integrates LA-ICP-MS zircon U–Pb ages and the first zircon trace element data from metasedimentary and metaigneous rocks of the Nyong Complex (NyC) in the NW Congo Craton, southern Cameroon, to constrain its petrogenesis, tectonic setting, and crustal evolution. Chondrite-normalized REE patterns [...] Read more.
This study integrates LA-ICP-MS zircon U–Pb ages and the first zircon trace element data from metasedimentary and metaigneous rocks of the Nyong Complex (NyC) in the NW Congo Craton, southern Cameroon, to constrain its petrogenesis, tectonic setting, and crustal evolution. Chondrite-normalized REE patterns show strong HREE enrichment, depleted LREE–MREE, and pronounced positive Ce and negative Eu anomalies, indicating a magmatic origin for the zircons. Trace element signatures suggest that the zircons derived from continental crustal magmas generated under variable oxidation conditions in a long-lived arc-related tectonic environment. Detrital zircon ages range from Archean to Paleoproterozoic, with five major age peaks at 2885 ± 8 Ma, 2775 ± 6 Ma, 2654 ± 7 Ma, 2469 ± 11 Ma, and 2316 ± 11 Ma. These ages correspond to major magmatic and metamorphic events recognized in both the Congo and São Francisco cratons. The preservation of felsic continental crust between 2.9 and 2.2 Ga in the NyC and the Borborema Province (NE Brazil) likely records a critical transition in Earth’s geodynamic regime, marked by enhanced consumption and recycling of mafic crust during Proterozoic accretion compared to the late Archean. This transition reflects the onset of modern-style plate tectonics, enabling craton stabilization and contributing to the assembly of the Nuna/Columbia supercontinent. The NyC is thus interpreted as part of the Trans-Amazonian belt, analogous to that in NE Brazil, and formed during the collision between the Congo and São Francisco cratons. Full article
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18 pages, 13801 KB  
Article
Enhancement of Impact Damage Identification by Band-Pass Filtering Digital Shearography Phase Maps and Image Quality Assessment
by João Queirós, Hernâni Lopes and Viriato dos Santos
J. Compos. Sci. 2026, 10(4), 207; https://doi.org/10.3390/jcs10040207 - 10 Apr 2026
Viewed by 832
Abstract
Composite materials are extensively used in the aeronautical and aerospace industries for their high strength-to-weight ratios but are vulnerable to barely visible impact damage (BVID), which can severely compromise structural integrity. Digital shearography (DS) provides a non-contact, full-field solution for subsurface inspection; however, [...] Read more.
Composite materials are extensively used in the aeronautical and aerospace industries for their high strength-to-weight ratios but are vulnerable to barely visible impact damage (BVID), which can severely compromise structural integrity. Digital shearography (DS) provides a non-contact, full-field solution for subsurface inspection; however, low signal-to-noise ratios in raw phase maps often hinder precise damage identification. This study explores a post-processing methodology utilizing a band-pass filtering algorithm and temporal summation to isolate damage-related spatial frequencies. An in-house digital shearography system was used to inspect a carbon-fiber-reinforced polymer (CFRP) plate subjected to 13.5 J and 26.2 J impacts. Twelve phase maps, acquired during the thermal cooling stage, were processed using a multi-pass filters to systematically analyze different frequency ranges. Results demonstrate that summing multiple filtered phase maps significantly enhances the contrast of damage signatures compared to single phase maps or traditional unwrapping techniques. Furthermore, quantitative assessment using image quality metrics, such as the generalized contrast-to-noise ratio (gCNR), confirmed that optimal frequency selection is essential for an accurate damage delineation. This approach provides a robust framework for improving the reliability and sensitivity of non-destructive testing in composite structures. Full article
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25 pages, 9398 KB  
Article
Genesis of the Middle Triassic Nare Alkaline Rocks in Gerze County, Tibet and Their Niobium–Tantalum Mineralization Potential
by Shichang Wang, Yujie Hao, Jianjun Fan, Yan Li, Xiaoheng Zhang, Weiye Zhang, Boyuan Wang, Mengting Zhao and Xue Bai
Minerals 2026, 16(4), 385; https://doi.org/10.3390/min16040385 - 4 Apr 2026
Viewed by 784
Abstract
This study investigates the origin and Nb–Ta enrichment mechanisms of the Middle Triassic Nare Alkaline Rocks in Gerze, central Tibet, using petrological, geochemical, and geochronological data. U–Pb zircon dating constrains the trachyte formation to the Middle Triassic, identifying NaOI as the oldest known [...] Read more.
This study investigates the origin and Nb–Ta enrichment mechanisms of the Middle Triassic Nare Alkaline Rocks in Gerze, central Tibet, using petrological, geochemical, and geochronological data. U–Pb zircon dating constrains the trachyte formation to the Middle Triassic, identifying NaOI as the oldest known seamount fragment in the zone and providing a key age for the early Meso-Tethyan Ocean. Whole-rock geochemistry data show the basalts possess typical OIB signatures, derived from a depleted mantle source modified by a mantle plume. The trachyte originated via a multi-stage process: Middle Triassic basaltic magmas underplated to form a deep-seated magma chamber, underwent high-pressure fractional crystallization, and the resulting crystal mush was later reheated and partially melted by subsequent magmas to generate trachytic melt. This model is supported by Hf isotopes and mineral chemistry. The rocks formed in a mature, thick-lithosphere intra-oceanic plate setting. Niobium occurs primarily as ilmenorutile with high Nb2O5 content, but its low modal abundance and very fine grain size imply low beneficiation recovery and limited current economic potential. However, the NaOI formed in an intra-oceanic island setting and hosts an early-stage Nb–Ta metallogenic system linked to alkaline magma differentiation, highlighting their potential for rare-metal exploration. Full article
(This article belongs to the Section Mineral Deposits)
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28 pages, 14728 KB  
Article
Decoding the Middle Tonian Tectonic Evolution of the Jiangnan Orogen, South China: Integrated Constraints from Volcano-Sedimentary and Magmatic Records of the Fanjingshan Region
by Yaran Dai, Jiawei Zhang, Taiping Ye, Tingting Zhang, Jianshu Chen and Lei Shi
Minerals 2026, 16(3), 334; https://doi.org/10.3390/min16030334 - 21 Mar 2026
Viewed by 728
Abstract
The Middle Tonian tectonic setting of the Jiangnan Orogen, South China, remains intensely debated, and is centered on two competing models: subduction–collision versus mantle plume. This study addresses this critical knowledge gap through an integrated, multi-proxy investigation of the Middle Tonian Fanjingshan Group. [...] Read more.
The Middle Tonian tectonic setting of the Jiangnan Orogen, South China, remains intensely debated, and is centered on two competing models: subduction–collision versus mantle plume. This study addresses this critical knowledge gap through an integrated, multi-proxy investigation of the Middle Tonian Fanjingshan Group. This region preserves a continuous volcano-sedimentary and magmatic record, offering key insights into the orogen’s full lifecycle. To test these hypotheses, we employed a synthesis of geological survey, sediment provenance analysis, detrital zircon U-Pb geochronology of clastic rocks to determine sediment provenance and basin evolution, and petrogenetic study of coeval magmatic suites (pillow lava, mafic–ultramafic sills, and granitoids) to evaluate their magmatic processes and tectonic setting. Analysis of 1736 detrital zircon U-Pb ages from Middle Tonian strata reveals a four-stage provenance evolution: (1) SW Yangtze sources in a passive margin basin before 870 Ma; (2) bidirectional sources in an 870–835 Ma arc-derived basin; (3) syn-collisional detritus during 835–820 Ma amalgamation; and (4) post-collisional and northern Yangtze inputs in an 800 Ma rifting basin. Geochemical data from ~845–840 Ma basalts and coeval sills reveal calc-alkaline affinities and marked subduction-fluid signatures. Their calculated mantle potential temperature (1404 °C) is significantly lower than that expected for plume-derived melts (1570 °C), which is consistent with melting in a subduction-modified mantle wedge, supporting a continental rear-arc basin setting. The ~845–832 Ma mafic–ultramafic sills exhibit symmetrical geochemical zoning and two-stage emplacement, recording sustained magma recharge in the rear-arc basin. Furthermore, the ~830 Ma Fanjingshan granite is identified as a crust-derived, syn-collisional S-type granite. Synthesizing these findings, we demonstrate that the sedimentary and magmatic records collectively point to plate margin setting. A four-stage tectonic model is suggested: (1) pre-870 Ma passive margin without significant magmatic activity; (2) 870–835 Ma continental arc development at an active continental margin; (3) 835–820 Ma Yangtze–Cathaysia collision; and (4) post-820 Ma post-orogenic rifting. This work provides a robust regional case study, demonstrating that integrating records of deep magmatic processes with coeval shifts in sedimentary provenance and basin architecture is essential to reconstruct the complete evolution of ancient orogens. Full article
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19 pages, 7600 KB  
Article
A Nonlinear Approach to the Delamination Characterization of Solid Structures Using Impact Response—Part I
by Yousef Sardahi, Asad Salem, Isaac W. Wait, Gang S. Chen, Kirk McCormick, Killian Blake, Tanner Samples and Luke Lanham
Vibration 2026, 9(1), 15; https://doi.org/10.3390/vibration9010015 - 26 Feb 2026
Viewed by 1365
Abstract
Impact-echo/impact response testing is widely used to detect cracks, voids, and delamination, but transient signals and crowded spectra can complicate diagnosis. This study presents a nonlinear, harmonic-based framework that characterizes delamination using higher-order harmonics in the impact-free response, instead of the amplitude-dependent resonance–frequency [...] Read more.
Impact-echo/impact response testing is widely used to detect cracks, voids, and delamination, but transient signals and crowded spectra can complicate diagnosis. This study presents a nonlinear, harmonic-based framework that characterizes delamination using higher-order harmonics in the impact-free response, instead of the amplitude-dependent resonance–frequency shift. The delaminated region is formulated as a locally vibrating nonlinear plate/oscillator with polynomial material and geometric nonlinearities, predicting harmonic components whose levels depend on impact intensity and nonlinearity parameters. The approach is validated on a concrete slab containing an artificial delamination, excited by repeatable impacts, and measured with an accelerometer. Frequency-domain analysis shows that intact regions exhibit a distinct spectral pattern, whereas the delaminated region produces a clear fundamental component and, with modestly increased impacts, a strong second harmonic that serves as a defect signature; time series metrics corroborate nonlinearity. The results demonstrate a nondestructive technique that can localize and characterize delamination without driving the specimen into damaging strain. Looking ahead, the same harmonic signature principle can be extended to vibroacoustic/impact monitoring of lithium-ion batteries to flag mechanically induced internal defects (e.g., separator/electrode delamination) that can precipitate internal short circuits and elevate thermal runaway risk, improving quality control and in-service safety. Full article
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25 pages, 22059 KB  
Article
Geochronology, Geochemistry, and Geological Implications of the Baiyingaolao Formation Volcanic Rocks in the Tulihe Area, Northern Great Xing’an Range, NE China
by Taotao Wu, Cong Chen, Yu Fan, Xiangxi Meng, Liangxi Chen, Qingshuang Wang and Yongheng Zhou
Minerals 2026, 16(2), 166; https://doi.org/10.3390/min16020166 - 31 Jan 2026
Viewed by 743
Abstract
The northern segment of the Great Xing’an Range, northeastern China, hosts a previously unrecognized near-E–W-trending rhyolite belt in the Tulihe area. We conducted systematic geochronological and geochemical investigations to constrain its formation age, petrogenesis, and regional tectonic significance. Field investigation, petrographic observation, and [...] Read more.
The northern segment of the Great Xing’an Range, northeastern China, hosts a previously unrecognized near-E–W-trending rhyolite belt in the Tulihe area. We conducted systematic geochronological and geochemical investigations to constrain its formation age, petrogenesis, and regional tectonic significance. Field investigation, petrographic observation, and zircon laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) U–Pb dating indicate that the rhyolite belt was formed during the Early Cretaceous, with emplacement ages directly determined from three samples ranging from 143.8 to 131.5 Ma. Geochemically, the rhyolites yielded high SiO2 contents (74.44–75.88 wt.%), high total alkalis (K2O + Na2O = 8.50–8.99 wt.%), and low MgO contents (0.16–0.55 wt.%). They displayed strong enrichment in light rare earth elements and depletion in high field strength elements, weakly negative Eu anomalies, A/CNK ratios near unity, and relatively high Nb/Ta ratios. Trace element signatures and incompatible element abundances (Zr + Nb + Ce + Y = 193.2–338.3 × 10−6) are mostly consistent with highly fractionated I-type volcanic rocks, rather than S-type or M-type affinities. The geochemical data suggest that the rhyolites were mainly generated by partial melting of a medium- to high-K basaltic lower crust, with minor crustal assimilation and limited mantle input. Tectonically, Early Cretaceous magmatism in the northern Great Xing’an Range was governed by flat-slab subduction and subsequent rollback of the Paleo-Pacific (Izanagi) plate, while the local E–W-trending rhyolite belt was controlled by pre-existing faults, reflecting localized post-orogenic extension consistent with regional NE-trending volcanic belts. The northwest-to-southeast younging trend records asthenospheric upwelling and enhanced crust–mantle interaction induced by slab rollback. These results highlight the petrogenetic and tectonic evolution of medium- to high-K magmatism along the NE Asian continental margin and improve our understanding of Mesozoic volcanism in the Great Xing’an Range. Full article
(This article belongs to the Special Issue Selected Papers from the 7th National Youth Geological Congress)
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29 pages, 4201 KB  
Article
The Effect of Boron Oxide on the Biocompatibility, Cellular Response, and Antimicrobial Properties of Phosphosilicate Bioactive Glasses for Metallic Implants’ Coatings
by Joy-anne N. Oliver, Qichan Hu, Jincheng Du and Melanie Ecker
Appl. Sci. 2025, 15(24), 13120; https://doi.org/10.3390/app152413120 - 12 Dec 2025
Cited by 1 | Viewed by 792
Abstract
Bioactive glasses remain promising candidates for enhancing osseointegration on metallic implants. However, achieving a composition that combines controlled dissolution, cytocompatibility, and antimicrobial functionality remains an ongoing challenge. Building upon the prior structural and thermal characterization of boron-substituted 6P55 phosphosilicate glasses, this study investigates [...] Read more.
Bioactive glasses remain promising candidates for enhancing osseointegration on metallic implants. However, achieving a composition that combines controlled dissolution, cytocompatibility, and antimicrobial functionality remains an ongoing challenge. Building upon the prior structural and thermal characterization of boron-substituted 6P55 phosphosilicate glasses, this study investigates the biological consequences of incorporating 0, 5, 10, and 15 mol% B2O3 to determine their suitability as coatings for Ti6Al4V. Glass extracts were evaluated using L-929 fibroblast cultures (MTT assay and ImageJ-based cell counting), antimicrobial assays against Escherichia coli and Staphylococcus aureus using a semi-quantitative dilution-plating method, and SBF immersion studies to assess pH evolution, surface mineralization, and Ca/P ratio development. FTIR and SEM analyses revealed composition-dependent formation of phosphate-, carbonate-, and silicate-rich surface layers, with 5B exhibiting the most consistent early-stage hydroxyapatite-like signatures, supported by Ca/P ratios approaching the stoichiometric value. The pH measurements showed rapid alkalization for 5B and moderate buffering behavior at higher boron contents, consistent with boron-dependent modifications to network connectivity. Cytocompatibility studies demonstrated a dose- and time-dependent reduction in cell number at elevated B2O3 levels, whereas the 0B and 5B extracts maintained higher viability and preserved cell morphology. Antibacterial assays revealed strain-dependent and sub-lethal inhibitory effects, with E. coli exhibiting stronger sensitivity than S. aureus, likely due to differences in cell wall architecture and susceptibility to ionic osmotic microenvironment changes. When considered alongside previously published computational and physicochemical results, the biological data indicate that moderate boron incorporation (5 mol%) provides the most favorable balance between dissolution kinetics, apatite formation, cytocompatibility, and antimicrobial modulation. These findings identify the 5B composition as a strong candidate for further optimization toward bioactive glass coatings on Ti6Al4V implants. Full article
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