Search Results (222)

This study investigates the wave-induced vertical mixing mechanism and systematically compares the application of two non-breaking wave parameterization schemes (Bv and Pw) in oceanic numerical simulations of the South China Sea, according to two key physical variables: sea surface temperature (SST) and the vertical mixing coefficient. The goal is to explore the effects of different parameterization methods on the upper-ocean temperature distribution in the South China Sea. The results indicate that although both schemes enhance vertical mixing in the upper ocean, they do so through different mechanisms. The Bv scheme directly increases the vertical mixing coefficient, demonstrating significantly stronger mixing intensity, while the Pw scheme impacts mixing indirectly by modulating turbulent kinetic energy generation, resulting in comparatively weaker mixing. SST simulation results show that the Bv scheme is more effective in reducing SST in both winter and summer, with broader spatial improvements. Further analysis of the mixing coefficient confirms that, compared to the Pw scheme, the Bv scheme not only strengthens surface mixing but also penetrates deeper into the water column. Full article

Asphalt plant reclaimed powder is a common solid waste in road engineering. Reusing reclaimed powder as filler holds significant importance for environmental protection and resource conservation. The key factors affecting the feasibility of reclaimed powder reuse are its acidity/alkalinity and cleanliness. Traditional evaluation methods, such as the methylene blue test and plasticity index, can assess reclaimed powder properties to guide its recycling. However, these methods suffer from inefficiency, strong empirical dependence, and high variability. To address these limitations, this study proposes a rapid and precise evaluation method for reclaimed powder properties based on Fourier transform infrared spectroscopy (FTIR). To do so, five field-collected reclaimed powder samples and four artificial samples were evaluated. Scanning electron microscopy (SEM), X-ray fluorescence spectroscopy (XRF), and X-ray diffraction (XRD) were employed to characterize their microphase morphology, chemical composition, and crystal structure, respectively. Subsequently, FTIR was used to establish correlations between key acidity/alkalinity, cleanliness, and multiple characteristic peak intensities. Representative infrared characteristic peaks were selected, and a quantitative functional group index (Is) was proposed to simultaneously evaluate acidity/alkalinity and cleanliness. The results indicate that reclaimed powder primarily consists of tiny, crushed stone particles and dust, with significant variations in crystal structure and chemical composition, including calcium carbonate, silicon oxide, iron oxide, and aluminum oxide. Some samples also contained clay, which critically influenced the reclaimed powder properties. Since both filler acidity/alkalinity and cleanliness are affected by clay (silicon/carbon ratio determining acidity/alkalinity and aluminosilicate content affecting cleanliness), this study calculated four functional group indices based on FTIR absorption peaks, namely the Si-O-Si stretching vibration (1000 cm⁻¹) and the CO₃²⁻ asymmetric stretching vibration (1400 cm⁻¹). These indices were correlated with conventional testing results (XRF for acidity/alkalinity, methylene blue value, and pull-off strength for cleanliness). The results show that the Is index exhibited strong correlations (R² = 0.89 with XRF, R² = 0.80 with methylene blue value, and R² = 0.96 with pull-off strength), demonstrating its effectiveness in predicting both acidity/alkalinity and cleanliness. The developed method enhances reclaimed powder detection efficiency and facilitates high-value recycling in road engineering applications. Full article

A novel modified oyster shell (MOS-800) was developed to enhance phosphorus sequestration and recovery from wastewater. Approximately 33.3% of phosphate was eliminated by the MOS-800, which also exhibited excellent pH regulation capabilities. In semicontinuous tests, a synergistic phosphorus separation was achieved through the coupling process of CaCl₂/MOS-800 and a circulating fluidized bed (CFB), resulting in an 86.5% phosphate separation. In continuous flow experiments, phosphorus elimination reached 98.2%. Material characterization revealed that hydroxyapatite (HAP) was the primary component of the crystallized products. Additionally, MOS-800 released 506.5–572.2 mg/g Ca²⁺ and 98.1 mg/g OH⁻. A four-stage heterogeneous crystallization mechanism was proposed for the coupling process. In the first stage, Ca²⁺ quickly reacted with phosphate to form Ca-P ion clusters, etc. In the second stage, these clusters packed randomly to form spherical amorphous calcium phosphate (ACP). In the third stage, the ACP spheres were transformed and rearranged into sheet-like HAP crystallites, Finally, in the fourth stage, the HAP crystallites aggregated on the surface of crystal seeds, also with the addition of crystal seeds and undissolved MOS-800, potentially catalyzing the heterogeneous crystallization. These findings suggest that the CaCl₂/MOS-800/CFB system is a promising technique for phosphate recovery from wastewater. Full article

The remarkable advantages of zinc anodes render aqueous zinc-ion batteries (ZIBs) a highly promising energy storage solution. Nevertheless, the uncontrolled growth of zinc dendrites and side reactions pose significant obstacles to the practical application of ZIBs. To address these issues, a straightforward strategy has been proposed, involving the addition of a minute quantity of AgNO₃ to the electrolyte to stabilize zinc anodes. This additive spontaneously forms a hierarchically porous Ag interphase on the zinc anodes, which is characterized by its zinc-affinitive nature. The interphase offers abundant zinc nucleation sites and accommodation space, leading to uniform zinc plating/stripping and enhanced kinetics of zinc deposition/dissolution. Moreover, the chemically inert Ag interphase effectively curtails side reactions by isolating water molecules. Consequently, the incorporation of AgNO₃ enables zinc anodes to undergo cycling for extended periods, such as over 4000 h at a current density of 0.5 mA/cm² with a capacity of 0.5 mAh/cm², and for 450 h at 2 mA/cm² with a capacity of 2 mAh/cm². Full zinc-ion cells equipped with this additive not only demonstrate increased specific capacities but also exhibit significantly improved cycle stability. This research presents a cost-effective and practical approach for the development of reliable zinc anodes for ZIBs. Full article

Detecting airborne viruses using an integrated aerosol sampling detection device is of great significance in epidemic prevention and control. Most of the applicable aerosol samplers have a flow rate of less than 1000 L/min, which is insufficient for application in large public spaces. Recent research, on the other hand, has revealed the advantages of microfluidic chip-based LAMP–CRISPR in airborne virus detection; however, this promising detection method has yet to be integrated with an aerosol sampler. Herein, we present an aerosol sampling and microfluidic chip-based detection (ASMD) device that couples a high-flow-rate aerosol sampling (HFAS) system with a microfluidic LAMP–CRISPR detection (MLCD) chip for surveilling airborne viruses, as represented by SARS-CoV-2. The HFAS system achieved a 6912 L/min flow rate while retaining a satisfactory collection efficiency, and achieved an enrichment ratio of 1.93 × 10⁷ that facilitated subsequent detection by the MLCD chip. The MLCD chip integrates the whole LAMP–CRISPR procedure into a single chip and is compatible with the HFAS system. Environmental detection experiments show the feasibility of the ASMD device for aerosol sampling and detection. Our ASMD device is a promising tool for large space aerosol detection for airborne virus surveillance. Full article

A metasurface capable of flexibly manipulating electromagnetic waves to realize holograms presents significant potential in millimeter-wave imaging systems and data storage domains. In this study, full-space three-dimensional holograms are realized from a reflection–transmission integrated reconfigurable metasurface, which can achieve nearly 360° phase coverage in reflection space and 180° phase coverage in transmission space. By adjusting the voltage applied to the constituting electronically tunable meta-atoms of the metasurface, an octahedron hologram constituted by three hologram images in different focal planes is generated in the reflection space at 6.25 GHz. Moreover, a diamond hologram, also composed of three hologram images in different focal planes, is achieved in the transmission space at 6.75 GHz. Both the numerical simulation and experimental measurement are performed to validate the full-space holograms implemented by the modified weighted Gerchberg–Saxton (WGS) algorithm with specific phase distribution in different imaging planes. The obtained results pave the way for a wide range of new applications, such as next-generation three-dimensional displays for immersive viewing experiences, high-capacity optical communication systems with enhanced data encoding capabilities, and ultra-secure anti-counterfeiting solutions that are extremely difficult to replicate. Full article

The air injection for brine drainage affects the thermodynamic characteristics of salt caverns in the operation of compressed air energy storage (CAES). This study develops a thermodynamic model to predict temperature and pressure variations during brine drainage and operational cycles, validated against Huntorf plant data. Results demonstrate that increasing the air injection flow rate from 80 to 120 kg/s reduces the brine drainage initiation time by up to 47.3% and lowers the terminal brine drainage pressure by 0.62 MPa, while raising the maximum air temperature by 4.9 K. Similarly, expanding the brine drainage pipeline cross-sectional area from 2.99 m² to 9.57 m² reduces the total drainage time by 33.7%. Crucially, these parameters determine the initial pressure and temperature at the completion of brine drainage, which subsequently shape the pressure bounds of the operational cycles, with variations reaching 691.5 kPa, and the peak temperature fluctuations, with differences of up to 4.9 K during the first cycle. This research offers insights into optimizing the design and operation of the CAES system with salt cavern air storage. Full article

Several trichomonad species have already been reported from cattle, including Tetratrichomonas buttreyi and Pentatrichomonas hominis. However, there is currently a lack of information concerning the prevalence of trichomonad species in cattle in Shanxi Province, North China. In this study, 761 fecal samples from cattle across three counties in Shanxi Province, namely Qi, Jishan, and Shanyin, were examined for the presence of T. buttreyi and P. hominis DNA through a nested PCR assay targeting a specific segment of the small subunit ribosomal RNA (SSU rRNA) gene. The results showed that the total prevalence of T. buttreyi in cattle was found to be 74.5%, with region and sex identified as risk factors for infection. P. hominis exhibited an overall prevalence of 3.0%, with strong associations observed between infection and both region and age. Sequencing analysis indicated that some T. buttreyi isolates and all P. hominis isolates were identical to those reported previously based on the analysis of SSU rRNA sequences, while certain T. buttreyi isolates exhibited minor allelic variations. These results enhance our understanding of the geographical distribution and genetic characterization of T. buttreyi and P. hominis in cattle. Full article

The polysaccharide of Millettia speciosa Champ. ex Benth (MSCP) has antioxidant properties, but its impact on chicken growth and development is not yet known. This study used chlortetracycline as a control to assess MCSP as a feed antibiotic substitute and its effects on Wenchang chicken production, slaughter performance, and meat quality. A total of 576 healthy 80-day-old Wenchang chickens were randomly allocated to six experimental groups. The control group (Control) received a basal diet, while the antibiotic group (CTC) was supplemented with 2 g/kg chlortetracycline (CTC). Four additional experimental groups were administered varying doses of MSCP: 400 mg/kg (MSCP₄₀₀), 800 mg/kg (MSCP₈₀₀), 1600 mg/kg (MSCP₁₆₀₀), and 3200 mg/kg (MSCP₃₂₀₀), respectively. The study discovered that incorporating MSCP and CTC into chicken diets significantly boosted the final body weight and average daily feed intake compared to the control group (p < 0.01), with MSCP notably enhancing average daily weight gain. With the addition of 800 mg/kg MSCP, chicken growth performance is comparable to that achieved with antibiotics in feed. However, it did not impact slaughtering performance (p > 0.05). In addition, MSCP significantly raised the pH after 24 h (p < 0.05) and decreased the yellowness (p < 0.01) of breast muscle. MSCP increased the essential amino acids (EAA) proportion in breast muscle (p < 0.05), EAA to nonessential amino acids (NEAA) ratio (p < 0.05), and diversity of fatty acids while decreasing C20:0 and increasing C18:2N6 and C22:1N9 content. Moreover, MSCP significantly reduced muscle fiber size (p < 0.01), increased fiber density (p < 0.01), boosted MYOD1 expression (p < 0.05), and decreased MSTN expression in breast muscle (p < 0.01). Overall, our study showed that supplementing the diet with MSCP, particularly at a dose of 800 mg/kg, enhanced growth, meat quality, muscle morphology, amino acid content, fatty acid composition, and gene expression related to muscle development in breast muscle. The results indicate that MSCP is a feed additive with the potential to replace antibiotics and improve meat quality, showing promising application potential. Full article

Ship carbon-emission monitoring is critical for implementing the IMO’s GHG reduction strategy. This study comprehensively introduces four methods for ship carbon monitoring and carbon calculation and systematically compares four vessel CO₂-monitoring methodologies, assessing their accuracy, influencing factors, real-time performance, and regulatory applicability. The analysis of China’s current carbon supervision framework informs proposed enhancements for low-carbon shipping governance. Full article

This study optimized ultrasound-assisted extraction (UAE) for polysaccharide isolation from Brassica rapa L. using Box–Behnken design, achieving a maximum yield of 41.12% under conditions of 60 °C, 60 min, 175 W ultrasonic power, and 30 mL/g liquid–solid ratios. The crude polysaccharide (BRAP) was purified via DEAE-52 cellulose and Sephadex G-100 chromatography, yielding BRAP1-1 with the highest recovery rate. Structural analyses (FT-IR, HPGPC, SEM, SEC-MALLS-RI) identified BRAP1-1 as a β-glycosidic pyranose polysaccharide (32.55 kDa) composed of fucose, rhamnose, arabinose, galactose, and galacturonic acid (molar ratio 0.81:4.30:3.61:1.69:89.59). In a humanized mouse model via fecal microbiota transplantation (FMT), BRAP1-1 significantly increased α-diversity indices (ACE, Chao1; p < 0.05) and altered β-diversity, with PCA explaining 73% variance (PC1: 60.70%, PC2: 13.53%). BRAP1-1 elevated beneficial genera (Lysinibacillus, Solibacillus, Bacteroides, etc.) while suppressing pathogens (Treponema, Flavobacterium, etc.). Six genera, including [Eubacterium]_coprostanoligenes_group and Bacteroidales (p < 0.05), correlated with acetic/propionic acid production. These findings demonstrate BRAP1-1’s potential to modulate gut microbiota composition and enhance intestinal homeostasis. Full article

The application of double-layer shell structure is very common in some situations that require complex loads and vibrations, such as key components such as the shell and wings of aerospace engines, and the shell of underwater vehicles. Many authors have conducted research on the vibration and acoustic radiation characteristics of double-layer cylindrical shells. By adding reinforcement and ribs between the double-layer cylindrical shells and optimizing structural design, passive vibration control techniques can effectively solve high frequency vibration problems, but the impact on mid to low frequency vibrations is still limited. Therefore, this article conducts theoretical research on a novel active vibration control method that inserts an active actuator between a double-layer cylindrical shell to achieve better mid low frequency vibration control effects. Firstly, the substructure admittance method is applied to analytically and dynamically model a double-layer cylindrical thin shell structure with active support, and the vibration power flow of the system is theoretically derived to evaluate the vibration reduction effect. Then, numerical simulation analysis was conducted on the influence of different configurations of six feedback control parameters, time delays, and other factors on the vibration power flow. Finally, based on the image, the conclusion is drawn that all six feedback control parameters can improve the vibration control effect of the coupled system to a certain extent, but not every feedback control parameter has a prominent effect, and the effective range of some parameters is relatively narrow. Full article

With the rising global demand for aquatic products, aquaculture has become a cornerstone of food security and sustainability. This review comprehensively analyzes the application of deep learning in sustainable aquaculture, covering key areas such as fish detection and counting, growth prediction and health monitoring, intelligent feeding systems, water quality forecasting, and behavioral and stress analysis. The study discusses the suitability of deep learning architectures, including CNNs, RNNs, GANs, Transformers, and MobileNet, under complex aquatic environments characterized by poor image quality and severe occlusion. It highlights ongoing challenges related to data scarcity, real-time performance, model generalization, and cross-domain adaptability. Looking forward, the paper outlines future research directions including multimodal data fusion, edge computing, lightweight model design, synthetic data generation, and digital twin-based virtual farming platforms. Deep learning is poised to drive aquaculture toward greater intelligence, efficiency, and sustainability. Full article

For coastal nations and regions, wave energy provides a localized energy solution, decreasing dependency on external energy sources and fostering the sustainable development of local economies. Effective wave height occurrence (EWHO) represents the availability of wave energy and is a crucial parameter for site selection for optimal wave energy. This paper systematically analyzes the distribution of EWHO in China seas areas using significant wave height (SWH) data in the fifth generation of ECMWF atmospheric reanalysis (ERA5) and key climate indices. Employing methods such as climate statistical analysis, linear regression, significance testing, and trend analysis, the study highlights the temporal and spatial distribution characteristics, variation trends, and correlations with climate indices of EWHO. This research aims to provide technical assistance and decision support for the development of wave energy at sea. The results indicate the following conclusions: (1) The high EWHO in the China seas is predominantly located in northern Nanhai, southern Donghai, and the eastern waters of the Philippine Islands. The EWHO is highest in winter. (2) The growth trend of EWHO is most notable in the sea area east of the line connecting the Ryukyu Islands, Taiwan, and the northeastern Philippines, peaking in spring and being relatively weak in winter. (3) The correlation between NINO3 and EWHO is most significant in Nanhai and the northeastern waters of the Philippines, peaking in February with correlation coefficients ranging from −0.30 to −0.50. Full article

To investigate the fire prevention and suppression characteristics of coal gangue slurry grouting in goafs and the enhanced regulatory mechanisms of additives, the slurry-forming performance of coal gangue slurry was tested. The effects of heating temperature, grouting thickness, and heating duration on the surface temperature distribution characteristics were analyzed. Temperature-programmed experiments were conducted to examine the influence of various additives on the spontaneous combustion propensity of coal gangue, with a comparative analysis of the inhibitory effects between ammonium polyphosphate (APP) and other additives. The results demonstrate that the prepared coal gangue slurry exhibited no segregation or sedimentation, with a plasticity index consistent with standard grouting material requirements, confirming its superior stability. The central, maximum, and minimum surface temperatures of the slurry showed polynomial functional relationships with heating temperature. Surface temperature initially increased and then decreased with grouting thickness, with 10 cm identified as the critical thickness for temperature transition. Overall, the central, maximum, and minimum surface temperatures increased progressively with rising heating temperatures. In addition, under all tested conditions, the average surface temperature remained below 80 °C for slurries with >5 cm grouting thickness, meeting fire prevention requirements. However, the CO and CO₂ concentrations increased significantly as heating temperatures rose from 100 °C to 300 °C. At grouting thicknesses of 9–12 cm, CO and CO₂ emissions occurred only at 300 °C and decreased with increasing thickness. The coal gangue slurry modified with ammonium polyphosphate (APP) additives exhibited optimal antioxidant performance, significantly suppressing CO and CO₂ emissions, which further diminished with higher additive dosages. The findings of this study provide critical insights into the fire prevention performance of coal gangue slurry grouting and the application of additives in this field. Full article