Search Results (4,596)

Organic amendments can alter soil structure, root development, and carbon cycling, yet their coordinated effects remain unclear. Based on a long-term field microplot experiment established in 2009, four amendment systems with equivalent annual N, P, and K inputs but differing in amendment properties and nominal annual organic-material C inputs were compared: maize straw with NPK (CS), pig manure compost with NPK (PMC), biochar with NPK (BIO), and biochar-based fertilizer (BF). After 15 years, dry-sieved aggregate distribution, CT-resolved air-filled pores (>30 μm), peanut root morphology, and easily oxidizable organic carbon (EOC), microbial biomass carbon (MBC), and dissolved organic carbon (DOC) were determined. PMC had the highest CT-resolved total and connected porosities (19.01% and 10.86%), a greater proportion of small macroaggregates, and the largest root surface area. CS produced a greater proportion and mean size of large dry-sieved aggregates and the highest bulk-soil MBC content. BIO and BF showed lower CT-resolved total porosity but greater isolated porosity, anisotropy, mean pore diameter, and pore fractal dimension (collectively termed CT-resolved macropore heterogeneity); these treatments were also associated with greater root volume or length and increased EOC and DOC contents in small macroaggregate- and microaggregate-sized fractions. Root length correlated more strongly with macropore heterogeneity than with total porosity. Because measurements were obtained once from 12 microplots, these relationships and SEM results represent exploratory associations rather than causal pathways. Overall, traditional amendments were associated with aggregation or macropore connectivity, whereas carbonized amendments were associated with greater macropore heterogeneity. BF had the highest percentage of EOC in TOC (52.45%), indicating a greater relative contribution of labile carbon, not increased stable carbon stock. Full article

Structural analysis using X-rays and electron beams has long provided the average arrangement of atoms and molecules—that is, “structural information”—with high precision. By contrast, static measurements cannot directly yield dynamic information on how a material changes over time; instead, information on motion is convolved into a single numerical value such as the B-factor (atomic displacement parameter). Taking this limitation as its starting point, this review surveys the recent trend of introducing a time axis into measurements to observe material dynamics directly. First, we outline the technological foundations that have made the transition from static to time-resolved measurement possible. It rests on the dramatic shortening of exposure times, enabled by the increased brilliance of X-ray and electron sources and by advances in detection technology such as direct photon-counting detectors. Next, we survey dynamic measurement techniques, including time-resolved X-ray crystallography, coherent X-ray scattering, neutron scattering, and time-resolved electron microscopy. We also point out the essential limitation that most of them still return ensemble or volume averages. Building on this, we systematically describe diffracted X-ray tracking (DXT), diffracted X-ray blinking (DXB), small-angle X-ray blinking (SAXB), transmitted X-ray blinking (TXB), and electron-beam molecular dynamics (EBMD), which use gold nanocrystals and gold nanoparticles as motion probes. We distinguish throughout between methods that follow individual objects—DXT and EBMD, which yield trajectories of single labeled molecules or single particles—and methods that analyze intensity fluctuations arising from many contributors within one pixel or illuminated volume—DXB, SAXB and TXB. The latter are not single-molecule measurements; rather, they replace a global ensemble average by a spatially localized statistical one, retaining local heterogeneity that a bulk measurement would average away. Finally, we discuss the implementation and prospects of the large-volume data analysis—principal component analysis, Bayesian inference, machine learning, and autonomous measurement—needed to handle the explosively increasing amount of information that the time axis introduces. We close with the outlook that time-resolved measurement incorporating AI and big-data analysis will become established as a new measurement platform that complements and extends conventional static structural analysis. Full article

Wittichenite Cu₃BiS₃ is a promising thermoelectric material with intrinsically low thermal conductivity owing to its complex crystal structure and strong lattice anharmonicity; however, its thermoelectric performance is limited by low carrier concentration and insufficient electrical conductivity. In this study, Cu₃Bi_1−xSn_xS₃ (x = 0.02–0.06) compositions were designed by substituting Sn⁴⁺ for Bi³⁺ sites, and dense single-phase bulk specimens were prepared using mechanical alloying followed by hot pressing. The effects of Sn doping on charge transport and thermoelectric properties were then systematically examined. Structural analysis confirmed that Sn was successfully incorporated into the Cu₃BiS₃ lattice without secondary phase formation, accompanied by anisotropic lattice contraction associated with the difference in ionic radii between Sn⁴⁺ and Bi³⁺. With increasing Sn content, the carrier concentration increased from approximately 10¹⁶ cm⁻³ to the 10¹⁷ cm⁻³ level, whereas the Hall mobility remained nearly unchanged, resulting in a substantial enhancement in electrical conductivity. Although the Seebeck coefficient decreased with increasing carrier concentration, the reduction was moderate, leading to an improved power factor of 0.10 mW·m⁻¹·K⁻² at 673 K. The thermal conductivity remained low, approximately 0.30–0.40 W·m⁻¹·K⁻¹, across the entire composition range, and the electronic contribution was less than 1%, indicating that heat transport was predominantly governed by the lattice contribution. These results demonstrate that Sn doping effectively improves the electrical transport properties while preserving the intrinsically low lattice thermal conductivity of Cu₃BiS₃. Consequently, a maximum ZT of 0.18 was achieved at 673 K, corresponding to a 64% improvement compared with the undoped specimen. Therefore, this study suggests that carrier concentration control via aliovalent doping is an effective strategy for enhancing the thermoelectric performance of wittichenite. Full article

This study presents an electrothermal coating approach for synthesizing cell-imprinted polymers (CIPs) on metallic microwires through localized resistive heating-induced polymerization. Imprinted polymers (IPs) are robust, cost-effective synthetic affinity materials widely used in sensing applications. However, conventional fabrication methods, including bulk and suspension polymerization, often lack spatial control, producing non-specific polymerization, heterogeneous coatings, and reduced sensor reproducibility. Electrochemical polymerization provides improved spatial control but requires specialized instrumentation and restricts monomer selection. Here, applying direct current (DC) to metallic microwires immersed in a prepolymer solution generated localized Joule heating, enabling controlled in situ polymerization and uniform coatings while minimizing undesired bulk polymerization. By optimizing the applied current and polymerization time, CIP coatings with tunable thicknesses were fabricated on gold-coated microwires. Under optimized conditions, ~6 µm thick coatings were imprinted using Salmonella templates. Scanning electron microscopy revealed bacteria-shaped cavities consistent with template removal and the formation of imprinted cavities. Rebinding experiments demonstrated enhanced bacterial capture, with CIP-coated microwires achieving ~70% capture efficiency, compared to 22% for bare microwires and 33% for non-imprinted polymer (NIP) controls. These results support the effectiveness of the proposed method for localized polymerization and demonstrate the enhanced capture of the template species by CIP-coated microwires relative to bare microwires and NIP-coated controls. Full article

Cement-based grouting materials with a high water-to-cement ratio are susceptible to connected pore development, chloride ingress, and mechanical degradation in chloride-bearing groundwater and marine environments. To improve resistance to NaCl attack, this study compared an unmodified cement-based grouting material (NC) with a polyacrylate-emulsion-modified material (PA). Mechanical properties, surface wettability, pore structure, phase assemblage, thermal behavior, functional groups, and microstructure were investigated under different NaCl concentrations (0%, 5%, 10%, and 15%) and immersion durations (28 and 90 d). This study systematically evaluates the coupled evolution of mechanical strength retention, surface wettability, pore structure, chloride-bearing phases, and microstructure in a bulk PA-emulsion-modified high-water-to-cement-ratio grouting material under graded NaCl exposure. The results showed pronounced concentration- and time-dependent effects. Low NaCl concentrations were associated with continued hydration and reaction-product filling, whereas higher concentrations and prolonged exposure led to pore coarsening and strength loss. PA modification improved the mechanical stability of the material in NaCl environments. After 90 d of immersion in 15% NaCl, the compressive and flexural strengths of the PA group were 23.60% and 22.53% higher than those of the NC group, respectively, while the corresponding strength-retention ratios were higher by 9.06 and 10.40 percentage points. Contact-angle and MIP results showed that PA reduced surface wettability and mercury-accessible porosity. After 15% NaCl exposure, the contact angle of the PA group remained 72.5°, compared with 40.1° for the NC group, while the porosity decreased from 38.11% in the NC group to 30.98% in the PA group. XRD, TG-DTG, and FTIR analyses indicated the formation and evolution of Friedel’s salt or other chloride-bearing AFm phases after NaCl exposure. Combined with SEM observations, the results indicate that PA mitigates NaCl-induced deterioration through reduced surface wettability, refined pore structure, regulated chloride-bearing product distribution, and improved matrix integrity. Overall, the findings establish a coupled surface–pore–phase–microstructure framework for understanding the enhanced NaCl resistance of PA-modified cement-based grouting materials. Full article

Suppressing thermally driven morphological evolution while preserving efficient charge transport pathways remains a critical challenge for improving the long-term stability of organic photovoltaics (OPVs). Herein, a soft polymeric matrix strategy based on gel-related soft material concepts is demonstrated for stabilizing bulk heterojunction (BHJ) morphology and simultaneously improving the efficiency and thermal durability of OPVs. The incorporation of an optimal 5 wt% polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) as a soft polymeric matrix component into a PM6:Y6 blend modulates the nanoscale morphology and local packing characteristics of the acceptor phase. These changes improve charge-transport balance and charge collection, increasing the power conversion efficiency (PCE) from 14.27% to 15.22%, corresponding to a 6.7% relative enhancement over the control device. More importantly, after 10 days of thermal aging at 85 °C, the SEBS device retains 87.1% of its initial PCE, compared with 72.5% for the control device. Complementary morphological and spectroscopic analyses reveal suppressed thermally induced structural evolution and aggregation in the SEBS-containing films. These findings demonstrate that a gel-related soft polymeric matrix can regulate BHJ organization and mitigate thermally driven morphological evolution, providing a simple strategy for addressing the efficiency–stability trade-off and realizing thermally robust OPVs. Full article

Efficient abrasive blasting requires precise control of abrasive mass flow, which is governed by both the metering system design and the flow properties of the abrasive material. This study investigates the influence of particle size distribution on the flow behaviour of brown fused alumina during discharge through a commercially available Thomson TV II metering valve. Four abrasive fractions (F220, F80, F46 and F24) were characterized in terms of particle size distribution, bulk density, moisture content, angle of internal friction, and flow function. The discharge behaviour was experimentally evaluated using a custom-built test stand for four valve opening positions. The results showed that the smallest valve opening caused unstable flow conditions, arching, and complete flow blockage for the coarsest fraction, whereas stable and repeatable discharge was achieved for various valve openings. Although the finest fraction exhibited the highest flowability according to the flow function, it did not achieve the highest mass flow rate, indicating that flowability alone was insufficient to explain the observed discharge performance. Instead, the F80 fraction provided the highest discharge performance under all stable operating conditions. These findings indicate that laboratory flowability indices alone cannot reliably predict abrasive feeding performance and should be evaluated together with bulk density and particle size distribution. The results provide practical guidelines for optimizing abrasive metering systems and contribute to improved process stability, abrasive utilization, and operational efficiency in automated abrasive blasting applications. Full article

Machine learning (ML) models trained on bulk-crystal descriptors are increasingly used to prescreen catalysts by predicting adsorption energies, yet reported performances often rely on random K-fold cross-validation that permits the same bulk formula to appear in both training and test sets. We construct a reproducible benchmark that fuses 936 CatApp DFT adsorption energies with bulk descriptors from the Materials Project for H*, O*, and OH* on metal and alloy surfaces. We compare random K-fold cross-validation with GroupKFold grouped by parsed formula, the latter mimicking the realistic task of predicting adsorption on entirely new catalyst compositions. Under formula-grouped evaluation, random CV materially overestimates apparent generalization performance, with the largest and most robust effects for H* and OH* (protocol-inflation gaps up to approximately 0.8). The H* and OH* results are based on only 20 and 31 unique formulas, so their GroupKFold Spearman point estimates should be read as directional evidence rather than quantitative estimates. O* shows a smaller and statistically fragile protocol-inflation signal and, even where composition-plus-bulk features improve Random Forest and Ridge, the usable signal is best described as a very coarse pre-filter within a limited domain. Bulk descriptors are adsorbate-dependent: they improve O* prediction for Random Forest and Ridge, but degrade H* and OH*—a qualitative, directional observation given the small formula counts—whose binding is poorly captured by bulk crystal descriptors, consistent with the established view that it is governed by surface-localized electronic structure. These results outline a realistic performance boundary for bulk-to-surface ML in this benchmark: O* can be very coarsely prioritized from bulk descriptors within a limited domain, whereas H* and OH* are unlikely to be quantitatively predicted from bulk descriptors alone and would benefit from surface-aware models. We therefore recommend that bulk-to-surface adsorption-energy benchmarks report formula-grouped cross-validation alongside random cross-validation as a more robust and transparent practice. Full article

This study presents a comparative evaluation of the wear performance of three hot-work tool steels—WCLV (1.2344), Uddeholm Unimax, and Uddeholm QRO 90 Supreme—for die forging applications. The materials were characterized in terms of hardness and bulk chemical composition using Vickers hardness testing and X-ray fluorescence spectroscopy. Tribological behavior was investigated using ball-on-disc tests, while industrial performance was assessed by analyzing forging punches after the production of 16,250 components. Surface degradation was quantified using optical profilometry and three-dimensional roughness parameters. Measured hardness values were 591 HV for WCLV, 622 HV for QRO 90 Supreme, and 639 HV for Uddeholm Unimax. The average friction coefficients were 0.88, 0.92, and 0.77, respectively. Unimax also exhibited the lowest volumetric wear, reaching 0.04683 mm³ (R19 mm) and 0.03384 mm³ (R22 mm), compared with 0.08646–0.13095 mm³ for WCLV and 0.09598–0.13635 mm³ for QRO 90 Supreme. This corresponds to approximately 45–70% lower wear relative to the other steels. Industrial trials confirmed improved surface stability of Unimax punches after service. The observed trends are consistent with differences in alloying content and the expected microstructural response associated with chromium and molybdenum additions. Overall, Uddeholm Unimax demonstrated the most favorable balance of hardness, friction behavior, and wear resistance. Full article

Vivipary adversely affects the production process of the cucumber seed industry and greatly limits the popularization of cucumber varieties. Identification of the cucumber seed vivipary phenotype and screening of vivipary-associated genes will provide important theoretical value and practical significance for solving this problem in agricultural production. In this study, cucumber near-isogenic lines with significant differences in vivipary traits (viviparous line F and non-viviparous line BF) were successfully screened and used to construct genetic populations. Bulk segregant analysis (BSA) and QTL-seq were performed to fine-map the major-effect quantitative trait locus associated with vivipary variation. Based on QTL and BSA analyses, CsaV3_3G044640 (designated CsCYP82D47), which encodes a cytochrome P450 family protein, was identified as a candidate gene associated with cucumber vivipary. CsCYP82D47 exhibits obvious tissue specificity and is highly expressed in leaves, sprouts, and seeds. However, no significant difference in CsCYP82D47 expression was detected between viviparous and non-viviparous cucumber materials. Further sequence analysis revealed multiple mutation sites in this gene between different genotypes. Specifically, the CYP82D47 protein in viviparous materials harbours one amino acid insertion (L63) and two missense mutations (M71L and S124L). In addition, the altered leucine residue distribution in viviparous cucumber may enlarge the substrate channel and enhance substrate catalytic efficiency, which may contribute to the vivipary phenotype. In summary, this study identifies a promising candidate gene potentially related to cucumber vivipary, which lays a foundation for further exploration of the molecular mechanism underlying cucumber vivipary and provides a potential genetic resource for cucumber molecular breeding. Full article

Graphite-based nanocomposites with nitrogen-rich covalent two-dimensional materials are promising for energy, catalytic and sensing applications, but their controlled construction remains challenging because both graphite and many covalent 2D materials consist of stacked sheets that are difficult to integrate homogeneously without prior exfoliation, dispersion, mixing, and restacking. Here, we explore a solvent-free strategy that uses melamine-confined graphite as a preorganized precursor for chemical transformations between graphene layers. We demonstrate that intercalated melamine can undergo reaction pathways analogous to those of bulk melamine, enabling not only the previously reported formation of graphite/g-C₃N₄ composites but also the construction of a new graphite/melem composite. The same concept is further extended to multicomponent solid-state reactions by introducing pyromellitic dianhydride, enabling the formation of new graphite/polyimide-linked two-dimensional material composites from either melamine or melem precursors. Comparison of one-pot and stepwise routes shows that precursor preorganization within graphite improves framework preservation, structural continuity, and morphological homogeneity. Overall, this work presents graphite interlayers as confined reaction environments for transforming simple nitrogen-rich molecules into integrated graphite/2D-material composites, providing a scalable platform for exploring solid-state chemistry and hybrid material synthesis between graphene layers. Full article

Modern separation and purification technologies increasingly require materials that combine high selectivity, chemical robustness, and long-term operational stability without compromising mechanical performance. Radiation- and radical-induced graft copolymerization addresses this need by generating radical sites on polymer backbones and introducing tailored functional groups through subsequent monomer grafting. Retention of bulk properties, however, depends on controlling radiation dose, polymer structure, oxygen, and irradiation conditions so that grafting is favored over chain scission, crosslinking, and embrittlement. This review critically examines recent grafting strategies for gas and liquid separation, water treatment, radionuclide management, and resource recovery. It relates radical generation, graft growth, structural control, and functional-group chemistry to material performance and process optimization. Attention is given to radiation-induced grafting and its integration with controlled radical polymerization, especially reversible addition–fragmentation chain-transfer polymerization, to regulate graft density, chain length, and architecture. Composite and interfacial approaches are also evaluated. The review discusses the requirements and remaining barriers to practical translation, including dose optimization, long-term stability, regeneration, reproducibility, scalability, and the need for techno-economic and life-cycle assessments. Full article

Searching by numerical simulation for structures with optimal damping properties among viscoelastic hollow cylindrical bodies with a filler is usually associated with a large amount of computation. Formulating the mechanical problem as one of natural vibrations and natural wave propagation makes it possible to evaluate the dissipative properties of such a structure independently of external force and kinematic actions, and thereby to reduce the computational cost substantially. The solution of the natural vibration problem for a piecewise homogeneous viscoelastic hollow cylindrical body with a filler yields complex natural frequencies, the real part of which represents the vibration frequency and the imaginary part the damping factor (attenuation rate). The mechanical behavior of the viscoelastic material is described by the linear Boltzmann–Volterra hereditary theory with a three-parameter Koltunov–Rzhanitsyn relaxation kernel, within which the material characteristics are represented by complex dynamic moduli—the shear modulus and the bulk modulus—that, as a rule, depend on frequency. In the natural vibration problem these moduli become functions of the real part of the sought complex natural frequency alone, which makes the standard eigenvalue procedures of commercial finite-element codes inapplicable. The paper presents an algorithm that removes this difficulty. The dispersion relation of the piecewise homogeneous cylinder is obtained analytically in the form of a complex determinant of order 12 for a two-layer and 18 for a three-layer configuration, the elements of which are Bessel and Neumann functions of complex argument; the global stiffness and mass matrices needed for the general configuration can be assembled automatically in a general-purpose finite-element code such as ABAQUS; the resulting complex characteristic equation is solved by Muller’s method—every iteration of which evaluates the determinant by Gaussian elimination with partial pivoting, so that no expansion of the determinant is required. The efficiency of the algorithm is demonstrated for a two-layer viscoelastic hollow cylindrical body with a filler, the outer load-carrying layer being made of Kh12 steel and the inner layer (the filler) of 30 L steel. The real and imaginary parts of the complex natural frequencies, of the phase velocities and of the attenuation are obtained as functions of the dimensionless wave number, of Poisson’s ratio, of the ratio of the layer radii and of the ratio of the instantaneous elastic moduli of the layers. Full article

Pectin, a natural biopolymer, is a cost-effective, biocompatible, non-toxic, abundant, and flexible material, making it suitable for recording high-quality bioelectric signals from the dynamic surface of the human body. In this work, pectin-based flexible bioelectrodes were developed for the non-invasive monitoring of biopotentials. The bioelectrodes are composed of pectin, polyaniline emeraldine salt (PANI-ES), glycerol, and polydimethylsiloxane (PDMS) and therefore abbreviated as PPGP. The PPGP electrodes demonstrated a bulk electrical conductivity of (7.54 ± 0.81) × 10⁻³ S/cm, a very low impedance of 34 Ω, and a high charge storage capacity of 4.63 ± 2.70 mC/cm². The surface morphology of the PPGP electrode plays a crucial role in enhancing biopotential signal detection by improving adhesion to skin contours. PPGP electrodes have been successfully used for high-fidelity electromyographic (EMG) bioelectric signal measurements. The developed PPGP bioelectrodes have the potential to advance next-generation human–machine interface (HMI) technologies and wearable healthcare systems, including prosthetic control, rehabilitation monitoring, and assistive communication devices. Full article

This study investigates the mechanical and tribological behavior of three composites with a ZrO₂ matrix stabilized with 1.75 mol% Y₂O₃ and containing 1 wt.% Al₂O₃, reinforced with TiC (A), TiC + ZrC (B), and TiC + WC + Mo₂C (C). The matrix powder was synthesized by chemical coprecipitation, and the composites were consolidated by spark plasma sintering at 1350 °C. Dry reciprocating sliding tests against 100Cr6 steel were performed at 10 and 25 N. Composite A exhibited the highest HV10 hardness (1268), while the indentation fracture toughness values were similar (6.41–6.57 MPa·m^1/2). Wear resistance did not follow the hardness ranking. At 25 N, composite A exhibited surface fragmentation and a specific wear rate of 2.52 × 10⁻⁶ mm³·N⁻¹·m⁻¹, while composite B showed extensive and heterogeneous transfer of steel-derived material. Composite C exhibited the lowest coefficient of friction and specific wear rate, reaching 0.392 and 7.04 × 10⁻⁸ mm³·N⁻¹·m⁻¹, respectively, at 25 N. EDS mapping revealed an area-integrated Fe content of 0.7 at.% for C, compared with 7.2 at.% for A and B. The superior wear resistance of C was associated with substantially lower steel-derived material transfer and a relatively smooth wear-track surface rather than with the highest bulk hardness. Full article