Search Results (8,817)

Biochar is a carbon-rich material produced from biomass pyrolysis whose properties can be tailored for various applications, including soil improvement, water purification, and catalysis. Its light absorption capacity also makes it promising for solar-driven processes like water evaporation. Photothermal membrane distillation (PMD) combines membrane separation with light-induced heating for efficient water purification. Unlike conventional membrane distillation, PMD utilizes light-absorbing materials to enhance vapor pressure and overcome temperature polarization, a common issue in membrane distillation. This study explored the potential of biochars and activated biochars, as filler materials for photothermal membranes, in line with circular economy principles. The mixed matrix membranes were prepared in a single step, via non-solvent induced phase separation starting from a uniform dispersion of the filler in a polyvinylidene fluoride solution. These materials exhibited great heating performance, reaching surface temperature up to 36 °C under a 125 W/m² light source. Increasing the biochar loading up to 15 wt.% resulted in an 85% increase in distillation flux under light irradiation. Full article

The large-scale generation of asphalt dust waste (ADW) has raised increasing environmental concerns, while its high-value utilization in cementitious materials remains insufficiently explored, particularly in terms of mechanical performance, durability-related properties, and integrated sustainability evaluation. In this study, a graded utilization strategy based on particle size was proposed to incorporate ADW into alkali-activated concrete paving blocks, in which fine ADW fraction (<0.075 mm) was used as a partial replacement of blast furnace slag (BFS), while the coarser ADW fraction was used as a partial replacement of river sand, aiming at sustainable pavement applications. In addition, two types of ADW with different lithologies, namely limestone ADW and basalt ADW, along with their combined system, were investigated. The results show that the incorporation of ADW effectively enhances the engineering performance of paving blocks. The compressive strength increased from 45.3 MPa to 56.6 MPa, while water absorption decreased from 5.3% to 4.1%. All mixtures satisfied the requirements for abrasion resistance and slip resistance, demonstrating their compliance with the performance criteria for pedestrian pavement applications. Among all mixtures, the combined use of limestone ADW and basalt ADW exhibited the best overall performance. The improved performance may be attributed to the combined effects of graded particle utilization and the potential compositional complementarity between calcium-rich limestone ADW and silica–alumina-rich basalt ADW, which is consistent with the denser microstructure observed in SEM images. In addition, the proposed strategy contributes to improved solid waste utilization and reduced consumption of natural resources, as reflected in the quantitative sustainability assessment. Overall, this study demonstrates that graded utilization of ADW is a feasible approach for developing alkali-activated paving materials, with promising performance and sustainability potential. Full article

Distributed fiber optic temperature sensing (DTS) monitoring technology is increasingly widely applied in oil reservoir water injection development. However, existing DTS interpretation methods for layered water injection processes have insufficiently considered the effects of multilayer injection and reservoir damage. To address this issue, this paper takes into account interlayer heterogeneity and reservoir damage and, based on the laws of conservation of mass and energy, comprehensively incorporates the effects of friction, the Joule–Thomson effect, thermal convection, and thermal expansion. By coupling wellbore pipe flow with formation seepage, a temperature profile prediction model for multilayer water absorption under steady-state water injection conditions is established. Comparative validation against classical models such as those by Babak and Nowak demonstrates that the proposed model achieves high computational accuracy. Using this model, the influence patterns of injection rate, tubing diameter, formation coefficient, and skin factor on wellbore temperature distribution are systematically analyzed: a higher injection rate leads to a smaller temperature rise in the injected water; a larger tubing diameter results in a greater temperature rise; the formation coefficient affects the temperature profile by regulating interlayer water absorption distribution, while reservoir damage (skin factor) has a relatively limited direct impact on the temperature profile. The model is applied to interpret DTS field data from Well A, and the water absorption rate of each sublayer is quantitatively obtained: the main water absorbing intervals are 1878.7–1897.5 m and 1919.5–1950.6 m, with water absorption accounting for 30.57% and 24.28% of the total injection rate, respectively, while the remaining intervals exhibit secondary water absorption. These interpretation results are in good agreement with earlier oxygen activation tests. This study provides a theoretical basis and analytical method for applying distributed fiber optic temperature measurement technology to monitor water absorption profiles in multilayer injection wells. Full article

Conventional optical imaging struggles to acquire clear images of underwater scenes in turbid water. In this paper, a new dual-DMD single-pixel 3D imaging (DSP3DI) system is designed and constructed to realize the 3D shape reconstruction in highly turbid water conditions. Leveraging the spectral dependence of the scattering coefficient of water on wavelength, the designed system uses a 532 nm laser as the illumination source to minimize scattering and absorption losses during light propagation, and two digital micromirror devices (DMDs) are used to generate phase-shifting fringe patterns and sampling patterns, respectively, and then uses a single-pixel detector to sequentially collect the spatial light field reflected from the surface of the object. A single-pixel imaging (SPI) method based on a cake-cutting strategy for Hadamard encoding reconstructs the deformed fringe images, from which phase information is recovered to calculate the 3D shape of objects. The experimental results show that the system not only achieves millimeter-level measurement accuracy but also successfully reconstructs the 3D shape of complex objects at a sampling rate of 10% and in turbidities as high as 40 NTU. The proposed system, characterized by its compact structure, high measurement accuracy, and strong scattering resistance, offers a novel solution for high-precision 3D imaging in highly turbid water. Full article

Objectives: Concentrated pills, as a modernization and upgrade of traditional pills, have achieved significant advancements in dosage form. However, their extended disintegration and dispersion times have become a major limitation to their therapeutic efficacy. Therefore, an in-depth study and explanation of the dissolution mechanism of concentrated pills, along with the development of processing technology to control dissolution time, has emerged as a critical bottleneck in improving the quality of concentrated pills. Methods: In this study, the Liuwei Dihuang (LWDH) concentrated pill, derived from the classical Liuwei Dihuang pill, was selected as a representative model. Two drying methods—hot-air drying and hot air–microwave combined drying—were comparatively investigated to evaluate their effects on dissolution time. The dissolution behavior was elucidated by analyzing water migration during the dissolution process, as well as the textural properties and internal structural characteristics of the pills using Low-Field Nuclear Magnetic Resonance (LF-NMR), Micro-Computed Tomography (Micro-CT), texture analysis, and other modern techniques. Results: The results indicated that: (i) The rate of water absorption during the dissolution process of the LWDH pill was influenced by the number and size of the internal pores. (ii) Hot air–microwave combined drying results in more pores and faster dissolution. (iii) High-Performance Liquid Chromatography (HPLC) fingerprints showed no significant differences in the active ingredients between the samples. Conclusions: The drying method significantly affected the internal structure of the pills, suggesting that controlling the drying process could address the prolonged dissolution time of concentrated pills. Full article

The efficient photocatalytic generation of hydrogen peroxide (H₂O₂) from pure water remains a formidable challenge, primarily due to the rapid recombination of photogenerated electron–hole pairs and insufficient redox potentials inherent in single-component photocatalysts. To address these issues, we designed and synthesized a heterojunction material comprising cadmium sulfide nanoparticles loaded on carbon spheres (CS@CdS). Under conditions utilizing pure water and ambient air, the CS@CdS composite achieves an H₂O₂ production rate of 1305 μmol·g⁻¹·h⁻¹, which is 3.1 and 3.6 times higher than that of pure CdS and CS, respectively, without the need for any sacrificial agents or external oxygen supply. Systematic characterization reveals that CS and CdS form a tightly coupled electronic interface, which significantly accelerates charge carrier separation and effectively prolongs the lifetime of photogenerated carriers, thereby boosting photocatalytic performance. Furthermore, the CS component extends the visible-light absorption range of the composite and functions as an electron acceptor to suppress charge recombination, collectively endowing CS@CdS with enhanced photocatalytic activity. Mechanistic studies indicate that H₂O₂ production over CS@CdS proceeds predominantly via a two-step single-electron oxygen reduction reaction (ORR) pathway. This work offers a viable strategy for constructing CS-based heterojunction photocatalysts for efficient H₂O₂ synthesis. Full article

Antibiotic contamination of water, particularly tetracycline (TC), poses significant environmental risks and requires sustainable treatment solutions. This study reports a green and cost-effective synthesis of a ZnO/chitosan nanocomposite (ZnO/CS) for photocatalytic TC removal. ZnO nanoparticles were synthesized using lime juice as a natural stabilizing agent and subsequently incorporated into a chitosan matrix. The physicochemical properties of the composite were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) surface area analysis. The results confirmed the successful formation of hexagonal wurtzite ZnO and strong interfacial interactions between ZnO nanoparticles and the –NH₂/–OH functional groups of chitosan. The incorporation of chitosan significantly increased the specific surface area from 10.7 to 21.7 m² g⁻¹ and reduced the band gap from 3.18 to 3.03 eV, thereby improving visible-light absorption. The photocatalytic performance was evaluated under varying pH, initial TC concentration, and catalyst dosage, with optimal conditions identified at pH 6, 20 mg/L TC, and 1 g/L catalyst. Under these conditions, the ZnO/CS nanocomposite achieved 94.1% TC degradation within 120 min under visible-light irradiation. Scavenger experiments revealed that •OH and •O₂⁻ radicals are the dominant reactive species, and a possible degradation mechanism was proposed. These findings demonstrate the potential of the green-synthesized ZnO/CS nanocomposite for antibiotic removal from aqueous environments. Full article

The integration of salt removal and structural consolidation remains a major challenge in heritage brick conservation. This research proposes a preliminary experimental setup for a dual-function microbial strategy using a single bacterium, Stutzerimonas stutzeri D1, capable of sequential denitrification (biocleaning) and ureolysis-driven microbially induced calcium carbonate precipitation (biocementation). After the pre-check assessment, which compared standalone, simultaneous, and sequential metabolic configurations, sequential denitrification followed by ureolysis (A→B) optimized functional compatibility, achieving 90.1% nitrate removal within 48 h and the highest precipitation rate during the biocementation phase. Application on authentic demolition waste (solid fired-clay brick specimens) demonstrated highly efficient nitrate reduction, alkalization (from pH value of 6.4 to 9.12), surface mineral deposition confirmed by visual inspection, SEM imaging, and XRD analysis. Furthermore, reduced water absorption (by 30%) and improved compressive strength (by 25%) for only 72 h of this dual treatment indicate a promising and holistic approach in the field of construction biotechnology of heritage brick conservation. These pioneer findings demonstrate that metabolic sequencing governs compatibility in dual-function bacterial systems and validate a sustainable, single-strain platform for combined biocleaning and biocementation of historic brick masonry structures. Full article

Tree bark, an abundant by-product of the timber industry, represents a promising feedstock for sustainable construction. This study investigates the thickness swelling, water absorption, hygroscopicity and mechanical (compressive strength) properties of insulation panels produced from hardwood bark (Tilia spp. and Robinia pseudoacacia) via hydromechanical treatment and a wet-forming process. The panels were produced without added adhesives, relying on the formation of hydrogen bonds during the drying phase to ensure structural integrity. Both bark-based insulation boards (thermal conductivity coefficient 0.055–0.057 W/m·K) showed similar hygroscopic behavior, reaching equilibrium moisture contents of max. 25% at 93.9% RH. Water absorption after 24 h immersion was highly material-dependent; Tilia-based panels showed 57.11 ± 5.81%, and Robinia-based panels 320.61 ± 11.34%. Thickness swelling remained low (max. 6% for Robinia), showing significant orthotropic anisotropy. At 10% compressive strain, the Tilia and Robinia bark-based panels showed compressive strengths of 188 ± 14.6 kPa and 298 ± 18.1 kPa, accordingly. These findings demonstrate that hardwood bark can be successfully valorized into high-performance, binderless insulation, supporting circular economic strategies. Full article

Hydrogels have emerged as a crucial category of polymeric materials in materials science due to their three-dimensional network structure and remarkable capacity for water absorption and retention. However, conventional single-function hydrogels do not satisfy the increasing demands of advanced applications in biomedicine and environmental engineering. This paper focuses on the design, preparation, and performance characterization of nanofiber-reinforced polyacrylamide hydrogels to overcome this limitation. A bilayer structure, consisting of tensile layers and actuator layers based on a polyacrylamide/sodium alginate (PAM/SA) matrix integrated with functional materials, was developed. Nanocellulose (CNF) was incorporated to regulate mechanical properties by adjusting its content ratio with PAM, while poly-N-isopropylacrylamide (PNIPAM) and multi-walled carbon nanotubes (MWCNTs) were added to confer photothermal responsiveness. The deformation of the hydrogel was induced by temperature changes resulting from infrared illumination. The results indicate that the CNF-reinforced hydrogels exhibit enhanced mechanical strength—with the tensile strength reaching 17 kPa (89% higher than pure PAM) and fracture strain approaching 900% when the CNF content is 0.44 wt.% and PAM/SA mass ratio is 4:1—and they display reversible thermosensitive responses (reaching 60 °C within 100 s under near-infrared irradiation) following the incorporation of carbon nanotubes. This paper presents a novel strategy for the development of multifunctional hydrogel-based actuated systems, expanding the application potential of hydrogels in human motion tracking and drug delivery. Full article

Background/Objectives: SHP2 (PTPN11) is a key regulator of RAS/MAPK signaling and a well-validated target in cancer and developmental disorders. Designing ligands for its catalytic site is challenging due to the pocket’s intrinsic flexibility and the presence of conserved structural water molecules critical for ligand recognition, which limits traditional discovery approaches. This study aimed to systematically identify and prioritize novel SHP2-binding candidates using a computational strategy that accounts for these challenges. Methods: An integrative computational workflow was applied, combining water-aware docking, large-scale virtual screening of 714,409 compounds, MM/GBSA binding free-energy analysis, AI-driven chemical space modeling using ChemBERTa, and microsecond-scale molecular dynamics (MD) simulations. The high-resolution catalytic PTP domain of SHP2 structure was analyzed to identify conserved water molecules (W711, W716, W726, W776) essential for reproducing the crystallographic binding mode of the reference ligand 3LU. Candidates were prioritized based on docking scores, physicochemical criteria, structural inspection, MM/GBSA energetic profiles, and occupancy of distinct chemical space regions. Results: Seven compounds were selected. SwissADME analysis confirmed favorable drug-likeness and GI absorption, with no BBB permeation. ChemBERTa embeddings revealed substantial structural novelty relative to known SHP2 inhibitors. 1 μs molecular dynamics simulations suggested stable binding of compound 4 (2-(3-methyl-2,6-dioxopurin-7-yl)acetate) and persistent interactions with the conserved water network. MM/GBSA evaluation subsequently highlighted its energetically coherent profile. Conclusions: The workflow prioritizes compound 4 as a promising and structurally innovative SHP2-binding candidate. This integrative strategy provides a generalizable approach for targeting proteins with flexible pockets, critical water networks, and limited scaffold diversity, offering a roadmap for challenging computational ligand-prioritization projects. Full article

Graphitic carbon nitride (CN) is a promising photocatalytic material, but its practical application is limited by small specific surface area, narrow light absorption range, and high photogenerated carrier recombination rate. To address these issues, this study synthesized boron-doped carbon nitride (BCN) and sulfuric acid-exfoliated boron-doped carbon nitride (BCND). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results confirmed that boron was successfully doped into the CN skeleton via B-N bonds. Scanning electron microscopy (SEM) and N₂ adsorption–desorption (BET) characterizations showed that acid exfoliation significantly increased the specific surface area of BCND to 68.80 m²·g⁻¹, much higher than that of CN (9.54 m²·g⁻¹) and BCN (15.98 m²·g⁻¹). UV–visible diffuse reflectance spectroscopy (UV-Vis DRS) analysis revealed that BCND had the narrowest bandgap (2.59 eV) among the three materials, which enhanced its visible-light absorption efficiency. Photoelectrochemical tests demonstrated that BCND exhibited the smallest charge transfer resistance and the highest transient photocurrent density (eight times that of CN), indicating efficient separation of photogenerated electron–hole pairs. Photocatalytic water splitting experiments showed that BCND achieved the highest Hydrogen production rate of 792.34 μmol·g⁻¹·h⁻¹, which was about 4 times that of CN (158.41 μmol·g⁻¹·h⁻¹) and 1.36 times that of 2.5% BCN (584.30 μmol·g⁻¹·h⁻¹). Free-radical trapping experiments indicated that hydroxyl radicals (·OH) played a crucial promotional role in Hydrogen production, while superoxide anions (·O₂⁻) exerted an inhibitory effect. The enhanced performance of BCND was attributed to the synergistic effects of boron doping (narrowing bandgap) and acid exfoliation (increasing specific surface area). A possible photocatalytic Hydrogen production mechanism was proposed based on the experimental results. This study provides a feasible strategy for the structural modification and performance optimization of g-C₃N₄-based photocatalysts for water splitting. Full article

In order to maximize the use of low-temperature heat sources for refrigeration, a Li-Br absorption chiller combined with single-effect absorption refrigeration cycle and two-stage absorption refrigeration cycle (STAC) was developed. Experimental research on STAC was conducted on a prototype with a refrigeration capacity of 500 KW. A numerical model validated by experimental data was used to study the refrigeration performance of STAC under variable operating conditions. Compared to single-effect units and two-stage units, STAC demonstrates remarkable heat source conservation capability and adaptability to a broad spectrum of heat source temperatures. This advantage renders the STAC unit more adaptable to new energy or waste heat scenarios characterized by unstable heat sources. As the inlet temperature of the hot water increases, the temperature difference between the inlet and outlet of the hot water also increases. When the inlet temperature of the hot water is 70 °C, 90 °C and 120°C, the temperature difference between the inlet and outlet of the hot water is 10 °C, 30°C and 70 °C, respectively. Both increasing the inlet temperature of hot water and decreasing the temperature of cooling water will enhance the cooling capacity and coefficient of performance (COP) of STAC. As the flow rate of chilled water increases, the refrigeration capacity of STAC will also increase, but the COP will first increase and then decreases Full article

Herein, we describe a versatile synthetic strategy for constructing Prussian Blue (PB)-coated polymeric nanocapsules (PB@nanocapsules) with tunable sizes and controlled PB loading. A soft template was first formed from a miniemulsion composed of water/chloroform/hexadecane (94.55:5:0.2, w/w/w), using P4VP₈₂-b-PDMAA₁₈₀ as a stabilizer and varying amounts of P4VP homopolymer as a hydrophobe and additional reactive site provider. Crosslinked nanocapsules were obtained by adding 1,2-bis-(2-iodoethoxy)ethane (BIEE) as a crosslinker. The resulting nanocapsules exhibited average hydrodynamic diameters ranging from approximately 282 nm (without P4VP homopolymer) down to 58 nm (with 0.01 g P4VP homopolymer), as determined by DLS and TEM. Subsequently, sequential coordination with sodium pentacyanoammine -ferroate(II) hydrate (Na₃ [Fe(CN)₅NH₃]), followed by the addition of FeCl₃, yielded a uniform PB coating, as confirmed by the appearance of a characteristic absorption peak at 780 nm in the UV–Vis spectra and a CN stretching shift from 2060 to 2070 cm⁻¹ in FT-IR. TEM and HAADF-STEM with EDX mapping revealed the homogeneous distribution of Fe across the nanocapsule shells. The PB loading could be further controlled by varying the Fe³⁺ addition (5.0 × 10⁻³–4.5 × 10⁻² mmol), with higher loading improving thermal stability. This rational design provides a robust and generalizable platform for engineering polymer–inorganic hybrid nanostructures with tailored functionalities. Full article

This study focuses on the development and comprehensive evaluation of the physicochemical, mechanical, and biological properties of composites based on polyhydroxybutyrate (PHB), chitosan (Ch), and hydroxyapatite (HA) for biomedical applications. DSC and FTIR spectroscopy showed that the addition of hydroxyapatite did not significantly affect the structure of the materials, but AFM data revealed a change in the surface morphology. Variations in RMS roughness ranging from 13 to 150 nm were observed for chitosan and the composites. The density of the HA-containing samples was 0.06–0.067 g/cm³, which is higher than that of the unfilled composite (0.056 g/cm³). Optimal hydrophilic properties (contact angle 38.9°) and elasticity (damping factor 0.064) were recorded for the sample with 10% HA (PChHA10). The water absorption varied: the addition of chitosan increased the value to 7.5 g/g, compared to 2.7 g/g for pure PHB, while HA slowed the swelling kinetics (more than 180 min). A biodegradation study revealed that samples containing 10–20% HA exhibited the highest stability in an enzymatic environment, while further increases in HA content resulted in increased degradation rates. The PChHA10 is considered to offer the balanced combination of properties. The potential applications of this material in medicine include its use as a scaffold for the in vitro cultivation of osteoblasts and chondrocytes, as well as for implantation in models of bone and cartilage defects in vivo. Full article