Search Results (556)

Organic–inorganic hybrid crystalline materials formed in multicomponent aqueous systems are of interest because their phase behavior and physicochemical properties can be controlled by composition and crystallization conditions. In this study, the phase equilibria and crystallization behavior of the ternary aqueous Ca(ClO₃)₂·2CO(NH₂)₂–CH₂ClCOOH·(C₂H₄OH)₃N–H₂O system were investigated over the temperature range of −24 to 60 °C using the visual-polythermal method. Experimental data obtained for the two boundary binary subsystems and eight internal sections were used to construct the polythermal phase diagram. The diagram revealed distinct crystallization fields corresponding to ice, Ca(ClO₃)₂·2CO(NH₂)₂·2H₂O, CH₂ClCOOH·(C₂H₄OH)₃N, and a separate crystallization region associated with a previously unreported crystalline phase with the proposed composition ClCH₂COOH·Ca(ClO₃)₂·(C₂H₄OH)₃N. The solid phase was isolated from its crystallization region, washed with cold distilled water, dried to constant mass, and characterized by complementary Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS), thermogravimetric analysis, derivative thermogravimetry, and differential scanning calorimetry (TG–DTG–DSC), and powder X-ray diffraction (PXRD). The experimentally determined Ca²⁺ and ClO₃⁻ contents were reasonably consistent with the proposed composition, while FT-IR spectroscopy revealed characteristic chlorate vibrations and changes in the vibrational environment of the organic component. SEM showed predominantly prismatic and plate-like crystalline morphologies, and EDS confirmed the presence of Ca, Cl, O, C, and N. Thermal analysis demonstrated multistage decomposition, with comparatively good thermal stability below approximately 150 °C. PXRD revealed a diffraction fingerprint distinct from those of the starting components and the corresponding physical mixture. Preliminary indexing of 19 principal reflections was consistent with a tetragonal candidate lattice with a = b = 7.7411(5) Å, c = 24.7182(10) Å, V = 1481.2(5) ų, and M₂₀ ≈ 23.0. The crystallographic analysis is considered preliminary because the diffraction profile was reconstructed from the available pattern and was not subjected to complete structure refinement. Overall, the combined phase-equilibrium, compositional, spectroscopic, morphological, thermal, and diffraction data support the isolation of a distinct organic–inorganic crystalline phase with the proposed composition. Full article

Unidirectionally macrochanneled tetragonal zirconia polycrystals (TZP) scaffolds, comprising elongated microporous frameworks, were fabricated via vat photopolymerization (VP) using a solution of 75 wt% camphene and 25 wt% 1,6-hexanediol diacrylate (HDDA) as a phase-separable, photopolymerizable vehicle. The camphene/HDDA solution underwent phase separation at 5 °C, accompanied by the recrystallization and dendritic growth of camphene, thereby generating three-dimensionally interconnected camphene crystal networks enclosed by HDDA. Following the photopolymerization of HDDA, the scaffolds were freeze-dried to remove the camphene crystals and subsequently heat-treated for debinding to eliminate organic phases, including photopolymerized HDDA, the dispersant, and the photoinitiator. The effect of sintering temperature on the geometry of the micropores and the densification of the TZP walls was examined. The optimum sintering condition (1500 °C for 3 h) enabled the creation of elongated micropores with a volume fraction of 61.17 ± 0.90 vol%, surrounded by highly densified TZP walls. The fabricated scaffolds exhibited well-defined macrochannels arranged in a hexagonal pattern, separated by microporous frameworks. Their overall porosity was as high as 74.65 ± 0.73 vol%, owing to the high framework microporosity. Despite their high porosity, the scaffolds achieved a compressive strength of 53.10 ± 8.19 MPa and a compressive modulus of 364.38 ± 70.90 MPa. Full article

Flexible wearable piezoelectric sensors have attracted increasing attention in human motion monitoring and motion classification applications due to their self-powered sensing capability and rapid response. In this work, poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) flexible piezoelectric films were fabricated using a phase separation method with different loading masses of PVDF-HFP to regulate the crystal structure and output signal characteristics of the films. X-ray diffraction and Fourier-transform infrared spectroscopy analyses demonstrated that an appropriate mass of PVDF-HFP promoted the formation of polar β-phase crystals, and the optimized film exhibited a β-phase content of 86.81%. The prepared films generated stable and distinguishable response signals under different gait conditions, indicating high potential for flexible motion sensing. Furthermore, machine learning-assisted motion classification was preliminarily performed based on the acquired sensing signals, achieving an accuracy above 90%. This work demonstrates the potential of phase-separated PVDF-HFP films for flexible gait sensing and wearable motion recognition applications. Full article

Yb³⁺-containing glasses and glass-ceramics are attractive photonic materials because Yb³⁺ can act simultaneously as a near-infrared absorber, an energy-transfer sensitizer, a luminescent center, and a composition-dependent modifier of glass structure and crystallization. This brief review focuses on crystallization from parent glasses to glass-ceramics and examines glass-network chemistry, local Yb³⁺ coordination, phase separation, viscosity, heating rate, treatment temperature, holding time control nucleation, crystal growth, phase selection, rare-earth partitioning, transparency, and optical performance. Representative oxyfluoride, phosphate, oxyapatite, borosilicate, and aluminosilicate systems are compared using thermal analysis, X-ray diffraction, electron microscopy, vibrational spectroscopy, and optical spectroscopy. The available data show that Yb₂O₃ or YbF₃ does not have a universal effect on crystallization: low concentrations can promote fluoride-rich clustering or lower the apparent crystallization barrier, whereas higher concentrations can increase packing density, stabilize the residual glass, change the competitive phase assemblage, or suppress crystallization. Crystallization-enhanced luminescence is most consistently obtained when Yb³⁺ and the activator partition into low-phonon-energy nanocrystals while crystal size and refractive-index mismatch remain sufficiently small to preserve transparency. This review also identifies major reporting gaps, including limited quantification of crystalline fraction, partition coefficients, luminescence lifetime, quantum efficiency, and long-term thermal stability. Practical design guidelines and unresolved questions are proposed to support the rational development of transparent Yb³⁺-containing glass-ceramics for lasers, sensing, optical amplification, and related photonic applications. Full article

Acidic fluoride-rich waste liquor from oxide etching in liquid-crystal display and integrated-circuit manufacturing is commonly treated by calcium precipitation, generating fine, impurity-bearing sludge with limited resource value. This study investigated a thermodynamics-guided route for the recovery of cryolite from acidic semiconductor waste liquor using batch experiments and continuous-flow assessment. Visual MINTEQ was used to screen aqueous speciation and solid saturation, while batch tests examined the Al/F molar ratio, pH, aging time, and temperature. Although cryolite was predicted to be supersaturated over a broad pH range, favorable fluoride removal occurred only within a narrower empirical window. At an Al/F molar ratio of 1.0:6, pH 6.5, an aging time of 2 h, and 20 °C, fluoride removal reached 79.6%. Under recirculating fluidized-bed operation, the principal cryolite phase was retained, and the SEM-derived mean particle size increased from 0.57 ± 0.10 μm in the batch system to 0.82 ± 0.15 μm in the continuous-flow system. These results demonstrate that dissolved fluoride in real acidic oxide-etching waste liquor can be converted into a separable cryolite-enriched solid. Full article

Perovskite tandem solar cells (TSCs) have emerged as a transformative photovoltaic technology, offering a viable pathway to surpass the Shockley-Queisser limit of single-junction devices by enabling broader solar spectrum utilization and reduced thermalization losses. This review provides a comprehensive overview of recent progress in perovskite-based TSCs, covering four major device architectures: perovskite/silicon, perovskite/CIGS, all-perovskite, and perovskite/organic TSCs. We systematically discuss the fundamental working principles, including bandgap engineering, charge generation and separation, and current-voltage matching, followed by an in-depth analysis of strategies for perovskite layer regulation, interface engineering, and transport-layer optimization. Key advancements, such as compositional engineering, defect passivation, crystallization control, and optical management, have synergistically pushed power conversion efficiencies (PCEs) beyond 34% for perovskite/silicon TSCs and over 28% for all-perovskite and perovskite/organic configurations. Despite these achievements, critical challenges remain, including material instability, halide phase segregation, lead toxicity, scalable fabrication, and cost-effective integration. This review also outlines future perspectives, emphasizing the development of lead-free perovskites, novel charge-transport materials, advanced encapsulation techniques, and large-area manufacturing processes. With continued interdisciplinary efforts, perovskite TSCs hold great promise for driving the global transition toward sustainable and low-carbon energy systems. Full article

Bulk heterojunction (BHJ) active layers in organic photovoltaics (OPVs) are nanostructured composites in which electron-donating and electron-accepting semiconductors form interpenetrating phases for exciton dissociation and charge transport. The power conversion efficiency (PCE) of these organic-organic nanocomposites is governed by structural features spanning multiple length scales: molecular packing and energy-level alignment at donor/acceptor (D/A) interfaces, phase-separation morphology and crystallite connectivity, and thin-film optical and charge-transport characteristics. Rational design of high-performance OPV nanocomposites requires multiscale numerical modelling that bridges quantum chemistry, mesoscale morphology simulation, and device-scale optoelectronic modelling. This review surveys and critically compares recent advances in the structural design and numerical simulation of OPV BHJ nanocomposites. At the molecular scale, we examine density functional theory and non-adiabatic molecular dynamics approaches for resolving charge-separation driving forces, interfacial energy-level alignment, and exciton dynamics. At the mesoscale, we discuss molecular dynamics, kinetic Monte Carlo, and electronic coarse-graining methods for describing phase separation, crystallization kinetics, morphology evolution, and charge transport. At the device scale, we review exciton-diffusion, optical transfer-matrix, and drift-diffusion models that quantitatively link morphology to photovoltaic performance metrics. The review also evaluates how machine learning, high-throughput screening, surrogate models, and generative design accelerate donor–acceptor selection and morphology optimization, while distinguishing benchmark predictions from experimentally validated design rules. Across these scales, we compare the strengths, assumptions, and validation limits of the principal modelling approaches. Finally, we highlight emerging multiscale integration frameworks, including sequential parameter-passing pipelines and differentiable digital-twin concepts. By framing OPV BHJ layers as nanocomposites whose performance bottlenecks map onto composite-design challenges such as interface integrity, phase connectivity, multiscale charge transfer, and degradation-aware design, this review connects OPV modelling with broader structural-composites thinking for next-generation organic solar cells. Full article

The development of biodegradable polymer composites from renewable resources is important for reducing dependence on petroleum-based plastics and improving the sustainability of short-life-cycle products. However, poly(butylene succinate) (PBS)/poly(lactic acid) (PLA) blends are generally immiscible, and the reinforcing effect of alkali-treated hemp stem fiber (HSF) on their mechanical, thermal, rheological, morphological, and biodegradation behavior remains insufficiently understood. This study investigates PBS/PLA biocomposites prepared at fixed blend ratios of 90/10 and 80/20 wt.% and reinforced with 5–20 phr alkali-treated HSF. Hemp stem fibers are treated using 5 wt.% NaOH, dried, sieved, and compounded with PBS/PLA blends in an internal mixer at 190 °C and 50 rpm for 15 min, and fabricated by hot compression molding at 190 °C for 13 min. The incorporation of HSF improves composite stiffness, with the highest Young’s modulus of 306 MPa observed for the 80/20/15 composition, representing a 71% increase over neat PBS. The maximum flexural strength reaches 48 MPa for 90/10/20, while the highest flexural modulus reaches 1377 MPa for 80/20/20, representing improvements of 21% and 77%, respectively. In contrast, tensile stress at break and elongation at break generally decrease with HSF incorporation because localized fiber agglomeration, incomplete matrix wetting, and interfacial gaps limit effective stress transfer, particularly at higher HSF loadings. The MFR exhibits composition-dependent, non-monotonic behavior. The addition of PLA initially increases the MFR relative to neat PBS, whereas higher HSF loadings generally reduce the MFR due to restricted polymer chain mobility and increased resistance to melt flow. FT-IR results indicate no strong chemical interactions among PBS, PLA, and HSF, while DSC shows nearly unchanged melting temperatures but composition-dependent changes in PBS crystallinity and crystallization behavior. FESEM confirms a phase-separated PBS/PLA morphology with embedded HSF. Soil burial tests show increased weight loss with higher HSF content and exposure time, confirming enhanced biodegradation. Full article

The work explores the effect of modifying thin ZnO and ZnO:V sol–gel films with graphene oxide (GO) dispersions on their structural and photocatalytic properties. The study has, for the first time, detected the effect of selective phase separation in sols, characterized by the separate crystallization of zinc and vanadium oxides upon adding GO dispersion into a mixed sol. Increasing the GO concentration in ZnO-VO₂ precursor sols improves the crystallinity of the material; films of the same composition without added GO are X-ray amorphous. Conversely, adding GO to unmodified ZnO sols causes a reduction in the crystallite size of the films, which increases with higher GO content. Notably, their photocatalytic activity varies non-monotonically: at 10 wt.% GO, it is minimal, while a further increase in the GO concentration leads to its improvement. An increase in the GO concentration in ZnO:V films causes a monotonically enhanced efficiency of photocatalysis. This may be related to the improved crystallinity and the formation of a percolation cluster from reduced graphene oxide. Full article

Driven by the rising frequency of extreme climatic events and the escalating demand for sustainable infrastructure, modern pavement materials must deliver enhanced resilience, structural stability, and environmental adaptability. This study presents the design and synthesis of a novel polyurethane-polyurea (PU-PUa) pavement binder, engineered via a synergistic framework combining nanoscale microphase separation and a hierarchical hydrogen-bonding network. Utilizing a streamlined, one-step synthesis approach involving an aliphatic isocyanate, a polyaspartic ester, polytetramethylene ether glycol, and 1,4-butanediol, the PU-PUa copolymer achieves distinct nanoscale phase separation between its hard and soft segments. Fourier transform infrared (FTIR) spectroscopy verifies the successful formation of characteristic PU-PUa moieties and a multi-scale hydrogen-bonding network, while DSC and DMA reveal SSC-dependent soft-segment mobility, crystallization/melting behavior, and viscoelastic relaxation. These intra- and inter-segmental interactions, together with thermally activated soft-segment transitions, establish the structural foundation for the macro-performance enhancement of the system. Comprehensive evaluations demonstrate that the PU-PUa binder exhibits excellent mechanical and highly tunable properties. Rheological measurements indicate that increasing the soft segment content (SSC) or incorporating an appropriate diluent concentration significantly lowers the system viscosity, thereby enhancing processing workability during mixing and paving. Contact angle goniometry reveals that the surface hydrophobicity of PU-PUa can be effectively regulated by adjusting the SSC, offering a viable strategy to optimize moisture damage resistance. Moreover, curing behavior analyses show that the polymerization kinetics are strictly governed by both the SSC and environmental temperature, where a lower SSC or elevated curing temperature accelerates strength development. Mechanically, the PU-PUa binder displays desirable surface hardness (>80 Shore A) and exceptional aggregate adhesion (>2 MPa), ensuring robust bonding stability and resistance to traffic-induced abrasion. Characterized by balanced tensile performance, the elongation at break of the binder can be tailored from 90% to 161%, while its tensile strength varies between 6.4 MPa and 17.8 MPa at intermediate temperatures, manifesting excellent resilience and cracking resistance. Overall, this molecular-to-macroscopic design strategy establishes the PU-PUa copolymer as a highly promising, durable binder for next-generation resilient pavement infrastructures. Full article

The Lower Cretaceous volcanic–sedimentary succession in the Dehui Graben of the southern Songliao Basin preserves critical records of syn-rift volcanism and basin filling in NE China. This study presents an integrated dataset of zircon cathodoluminescence (CL) imaging, LA-ICP-MS U-Pb geochronology, trace-element geochemistry, and LA-MC-ICP-MS Lu-Hf isotopic analyses for four representative Yingcheng Formation samples collected from three boreholes (D102, D21, and D83) in the Dehui Graben. Zircon grains from samples S1 (gray crystal-vitric tuff, Well D102, 3050.5 m) and S3 (gray tuff, Well D21, 2287 m) are predominantly euhedral to subhedral with well-developed oscillatory zoning, elevated Th/U ratios (>0.4), and chondrite-normalized REE patterns characterized by depletion in light REEs, enrichment in heavy REEs, and pronounced negative Eu anomalies, all of which are diagnostic of a magmatic origin. The 37 zircon analyses from S1 yield ²⁰⁶Pb/²³⁸U ages ranging from 109 to 122 Ma, with a KDE peak at ~116 Ma and two inherited grains at 158 Ma and 262 Ma, whereas the 43 analyses from S3 define a narrow age population between 110 and 123 Ma with a KDE peak at ~114 Ma and a single inherited grain at 145 Ma. Together, these ages constrain Yingcheng Formation felsic volcanism in the Dehui Graben to the Aptian stage of the Early Cretaceous. In marked contrast, the 54 zircon analyses from S2 (dark gray crystal-rich tuff, Well D21, 2288 m) exhibit a polymodal distribution dominated by an Early Jurassic population (KDE peak ~181 Ma), with subordinate Permian–Triassic (~251 Ma) and Carboniferous (~325 Ma) components and a complete absence of Cretaceous-aged zircons. We interpret this population entirely as inherited (xenocrystic) zircons entrained from conduit wall rocks during the incipient phase of volcanic eruption. Notably, S2 and S3 were collected from the same well at depths separated by only 1 m, yet they display fundamentally contrasting zircon age spectra. This abrupt vertical discontinuity is consistent with a two-phase eruptive model in which an early xenocryst-rich volcaniclastic unit (S2), possibly related to conduit-wall entrainment during the initial eruptive stage, was rapidly followed by a juvenile magma-derived tuff (S3). Sample S4 (gray coarse sandstone, Well D83, 3273 m) contains 84 detrital zircon grains spanning 112 to 440 Ma, with a dominant Early Jurassic peak (~179 Ma) that correlates with widespread granitoids in the Zhangguangcai Range and a youngest single-grain age of 110.5 Ma that constrains the maximum depositional age of the Yingcheng Formation. All 86 zircon Lu-Hf analyses yield positive εHf(t) values (+0.8 to +9.2), with two-stage Hf model ages (TDM2) clustering between 536 and 1100 Ma and peaking at ~700–800 Ma (Neoproterozoic). These data indicate that the parental magmas were predominantly derived from partial melting of Neoproterozoic juvenile crust extracted from a depleted mantle source. Among the four samples, S3 records the highest mean εHf(t) (+7.1) and the youngest mean TDM2 (~672 Ma), which may indicate a relatively stronger depleted-mantle affinity during the extensional stage at ca. 114 Ma. The positive εHf(t) values of the ~181 Ma S2 xenocrysts further imply that the Early Jurassic magmatic event in this region also sampled juvenile Neoproterozoic crust, which thus served as the common source basement for both episodes of magmatism. A regional compilation reveals a systematic north-to-south younging trend of syn-rift volcanism across the Songliao Basin (Yingtai ~119 Ma, Dehui ~115 Ma, Wangfu ~110 Ma), with the Dehui Graben occupying a critical intermediate position that is consistent with the southeastward migration of back-arc extension possibly related to Paleo-Pacific slab rollback. Full article

Phase transition or phase separation occurs in cells and tissues in many physiological events, such as protein granules (P granules) in early C. elegans development. Inappropriate phase transition is often associated with pathologic processes such as RNA–protein complex (RNP) and FUS-mutation-associated diseases. Given its ubiquity, phase transition has been considered a new frontier for comprehending physiological processes and pathological diseases. However, molecular and cellular mechanisms of phase transition in situ remain poorly described. Combining histochemistry with polarization analysis and biochemical thin-layer chromatography, we identified a massive phase transition change during the development of Taihe fowl (Gallus gallus domesticus Brisson). During embryonic day 12 (E12), the livers of these Silkie chicken demonstrated a sudden massive transition from hepatic lipid droplets (HLD) into hepatic liquid crystal droplets (HLCDs). We identified these changes by characterizing the sudden appearance of birefringent Maltese crosses (MCs) typical to liquid crystals (LC) where non-birefringent lipid droplets used to reside within hepatic cells. LC status was confirmed by fluidity with shape-changing and in vitro thermal phase transition tests. These HLCDs were present consistently until the early postnatal days after hatching. Using thin-layer chromatography combined with X-ray diffraction analysis, we determined that these HLCDs were composed of cholesterol, cholesterol ester and lecithin, which are the same as the components of cytoplasmic membrane. There was no change in the quantity of lipid components during liver development to suggest a critical mass of components triggering these changes. However, expressions of membrane-associated autophagy markers LC3A and Beclin 1 increased dramatically during this HLD to HLCD transition. Increases in membrane-associated LC3A and Beclin 1 are localized with massive increases in membrane lipid components of HLCDs. Areas with enhanced LC3A and Beclin 1 signaling have been associated with liquid crystal MCs to the thickness of 69 Å (Bragg d value). These associations indicate the possible regulatory role autophagy plays during liquid crystal phase transition in embryonic liver development. Reactivation of this autophagy pathway may be a possible mechanism behind the development of non-alcoholic fatty liver disease in adulthood. Full article

This article presents the results of experimental studies on the production of chromium–nickel ferroalloy from the nickel ore of the Batamshinskoye deposit by the metallothermic method. Boron-containing ferrosilicochromium was used as a complex reducing agent and alloying material, and lime was applied as a fluxing component to control the composition and basicity of the slag. Laboratory smeltings were carried out in a Tammann furnace and an induction furnace at a temperature of 1630–1650 °C, producing slags with different basicities—0.4, 0.5, and 0.6. It was established that the use of boron-containing ferrosilicochromium provides the effective reduction of nickel, chromium, and iron oxides with the formation of a complex ferroalloy containing Fe, Cr, Ni, Si, and B. It is shown that an increase in slag basicity contributes to a decrease in its viscosity, a reduction in the content of chromium oxides in the slag, and an improvement in the conditions for the separation of the metal and slag phases. The crystallization temperatures of the slags, which decrease from 1410 to 1335 °C with an increase in basicity from 0.4 to 0.6, were determined by the method of semi-logarithmic processing of viscosity polytherms. The slag basicity range of 0.5–0.6 is recognized as optimal for the process. Full article

Calcite habit engineering offers a route to transform CO₂ mineralization from bulk sequestration into value-added nanomaterial production. Here, we demonstrate that additive chemistry and seeding strategy can serve as separable, recipe-level levers for directing calcite habit formation within a unified CaO/Ca(OH)₂ gas–liquid carbonation platform. This strategy highlights how solution-mediated habit control can bridge fundamental calcite crystallization mechanisms with scalable CO₂ utilization and value-added carbonate nanomaterial production. Sodium glutamate yielded ~100 nm rhombohedral nanoparticles, staged MgSO₄/ZnSO₄ dosing produced whisker-like crystalline nanorods with aspect ratios of 4–7, and two-step seeded carbonation with NH₄Cl generated fusiform spindle subunits that assembled into hierarchical rosette architectures. X-ray diffraction confirmed calcite as the only crystalline calcium carbonate phase detected under the present measurement conditions, with no detectable aragonite or vaterite reflections. SEM/TEM revealed distinct primary-subunit architectures, including internal striations in spindle particles indicative of oriented attachment. Thermogravimetry, N₂ physisorption, and EDS further distinguished the products and showed that Mg/Zn/S modifiers in the whisker route are retained predominantly at crystal surfaces rather than incorporated into the calcite lattice. These results define calcite habit control through two independent levers: additive-driven facet selectivity and kinetic decoupling of nucleation from growth/assembly. The platform links scalable synthesis, CO₂ utilization, and functional carbonate design. Full article

Molecular transport membranes are promising alternatives to conventional cryogenic separation processes. Here, solvent polarity effects were investigated by varying the DMF/MeOH ratio during the solvothermal synthesis of supported ZIF-7 membranes. A DMF:MeOH ratio of 1:3 preserved the characteristic sodalite topology while suppressing dense-phase formation. Methanol incorporation modified heterogeneous crystallization behavior, intercrystalline organization, membrane morphology, and film densification on α-alumina supports while reducing DMF consumption by approximately 75%. These effects are associated with solvent-mediated precursor solvation, Zn²⁺–benzimidazole coordination equilibria, and heterogeneous nucleation at the support–solution interface. Although low BET surface areas were obtained from N₂ adsorption at 77 K, these values were interpreted cautiously considering the known limitations of nitrogen physisorption in flexible ultramicroporous frameworks. Overall, the results support solvent polarity engineering as a physicochemical strategy for regulating membrane microstructural evolution under reduced DMF conditions. Accordingly, the transport behavior discussed herein is interpreted primarily from a solvent-mediated microstructural perspective rather than as a direct quantitative descriptor of accessible porosity. Full article