Silver nanoparticles (AgNPs) have attracted considerable attention for their potent antiproliferative properties. The search for efficient anti-lung cancer therapeutics led to the biosynthesis of AgNPs from a cyanobacterium, Leptolyngbya valderiana (Gomont) Anagnostidis & Kom & aacute;rek. Within 72 h of exposure of algal biomass to 0.01 M AgNO3, a notable color change of extracellular medium from transparent to dark brown was demonstrated, indicating successful synthesis of Leptolyngbya valderiana-AgNPs (LV-AgNPs). Furthermore, LV-AgNPs were characterized revealing their crystalline nature, oval shape, with sizes averaging 50 +/- 21.4 & times; 39 +/- 14 nm and a specific Ag absorption peak at 3 keV. Biosynthesized nanosilver showed remarkable antiproliferative efficacy against lung cancer cells A549 with an IC50 value of 19.78 +/- 1.296 mu g/mL and had a negligible effect on BEAS-2B and HEK-293 normal cells. Prominent alterations in cellular and nuclear morphology revealed an increased number of disintegrated A549 cells with condensed and fragmented nuclei. Microscopic evaluation of cell death was followed by flow cytometric cell cycle analysis, where the expansion of the sub-G0 population reflected that LV-AgNPs targets G0/G1 phase. Cell death was also associated with the formation of endogenous ROS and disruption of mitochondrial membrane permeability. The above findings suggest that silver nanomaterials produced by L. valderiana can serve as an alternative nano-drug development for lung adenocarcinoma.
To solve the problem that the traditional spray dust suppression method cannot efficiently capture the respirable fine dust in coal mine, the high humidity and high temperature two-phase jet dust suppression technology was developed. In this work, a gas-liquid thermodynamic coupling experimental device was designed and built to evaluate the effects of different parameters on the atomization characteristics of this technology and to verify the dust suppression performance. The results indicate the uniformity of the spray distribution and the gas-liquid phase transition can be greatly improved by improving the thermodynamic performance of the system; The flash evaporation effect was intensified and the surface tension of the liquid was reduced under the optimal operation conditions of water supply temperature of 90 degrees C, gas supply temperature of 100 degrees C, gas supply pressure of 0.4 MPa and water flow rate of 150 mL/min. The average relative humidity of the whole field was 84.6% with a maximum of 94% locally; the median droplet size (SMD) was 10.71 mu m with a dust suppression efficiency of 93.7%. This technology solves the shortcomings of the traditional methods and provides an efficient, innovative technical solution to control respirable dust in the mining industry.
In tapered pipes commonly used in engineering applications, increasing the particle mass flux and reducing specific energy consumption are key to improving the energy efficiency of liquid-solid two-phase conveyance. This study introduces the Witoszynski curve as the profile for tapered pipes and analyzes its transport characteristics in two-phase liquid-solid flow. The contraction ratio, contraction angle, and profile type were selected as optimization parameters, and the back propagation neural network (BPNN) and the genetic algorithm (GA) were employed as the prediction model and optimization algorithm. An optimization framework was developed to determine the optimal structural parameters for tapered pipes. The results show that using the Witoszynski curve as a contour guide allows particles to follow a smoothly varying curvature trajectory through the transition zone, thereby increasing particle velocity and improving flow field uniformity. Compared to the tapered pipes before optimization, the particle mass flux increased by 11.85%, and specific energy consumption decreased by 9.90%. Validation simulations conducted under various flow rates and with fluids of different viscosities demonstrate that the optimized model exhibits good robustness.
The pressure field within a pelletizer die during biomass pelletization remains largely uncharacterized, limiting the development of mechanistic models for pelletizer design and optimization. To address this gap, pressure conditions within a stationary die biomass pelletizer were investigated using sensors installed at three depths (0.78, 1.98, and 2.31 cm from the die entry) in a 29.8 mm-thick die. A flat-die pelletizer was instrumented with miniature pressure sensors installed at three die depths and thermocouples at corresponding locations, enabling real-time, in situ measurement of pressure and temperature during pelletization for the first time. Real-time pressure and temperature were recorded during pelletization of switchgrass and willow. Both feedstocks exhibited distinct peak pressure spikes, caused by the roller forcing material into the die, and baseline pressure plateaus between spikes. Peak pressures for switchgrass reached 6.86, 3.10, and 0.59 MPa at the top, middle, and bottom sensor locations, respectively, while willow registered slightly higher values of 8.59, 3.25, and 1.10 MPa. Pressure fluctuations were most pronounced at the top sensor, reflecting the roller's intermittent feeding action. The baseline pressure represents residual frictional resistance in compacted biomass, preventing material spring-back between roller passes. Temperature was highest at the top of the die, with the greater drop occurring between the middle and bottom sensors. These findings inform the development of viscoplastic compaction models and suggest that controlling pressure and temperature conditions can impact pellet quality. This study provides foundational data for designing more efficient pelletizers tailored to specific biomass feedstocks, advancing bioenergy production technologies.
To address coal dust emissions at the feeding and discharging ports of belt conveyor transfer points, this study proposes a pressure-enhanced dust suppression system based on a supersonic spray fortress. A coupled numerical and physical model of the transfer point was established, incorporating assumptions of coal flow-induced airflow, tangential distribution of induced effects, and incompressible fluid behavior. The multiphase gas-particle-spray flow was characterized using the Stokes equation for particle motion and the standard k-epsilon turbulence model. The supersonic spray fortress was designed as an irregular hexahedral metal structure integrating gas-liquid pipelines and equipped with three supersonic atomizing nozzles arranged at composite angles (45 degrees horizontal spacing and 45 degrees downward inclination). A geometric model of the coal conveying system was constructed, and mesh independence verification was conducted to ensure the reliability of numerical simulations. Spray characteristics were experimentally investigated using a Winner319 laser particle size analyzer and a three-dimensional particle image velocimetry (3D-PIV) system, enabling measurement of droplet size parameters (SMD, V50, N50) and velocity under pressures ranging from 0.2 to 0.4 MPa. Field experiments were performed at a coal mine transfer point to monitor dust concentrations before and after system implementation. The results indicate that spray characteristics are highly sensitive to operating pressure. As pressure increases from 0.2 to 0.4 MPa, droplet SMD decreases from 65-70 mu m to 30-45 mu m, while initial velocity increases from 12 to 20 m/s; droplet size shows minimal variation with distance. The spray fortress significantly regulates the airflow field, reducing peak airflow velocity by more than 60% (from >10 to <= 4.8 m/s) and decreasing the proportion of high-velocity regions (>5 m/s) from 35% to <= 8%. In terms of dust behavior, peak dust velocity decreases by over 70% (from >20 to <= 6 m/s), accompanied by a substantial reduction in coarse particles (>10 mu m). Field application results show that within a range of -10 to 15 m, the total dust removal efficiency reaches 51.4-93.4%, while respirable dust removal efficiency is 44.6-87.9%. The dust particle size distribution shifts toward finer fractions (0-2.5 mu m), primarily due to the effective capture of medium and coarse particles by spray droplets. The supersonic spray fortress achieves synergistic regulation of airflow and dust transport through mechanisms such as momentum offset, spatial coverage, and collision capture. With optimized spray parameter configuration and strategic placement at the upper and lower ports of the chute, a full-process dust control system is established, providing a reliable and effective solution for dust mitigation at belt conveyor transfer points.
Research into new filter tip materials capable of adsorbing harmful substances in cigarette smoke has long been a focus of the industry. In this study, Scutellaria baicalensis carbon nanocomponents (SRC-NCs) were prepared using Scutellaria baicalensis as the carbon source. The particle size was approximately 10-24 nm. The carbon spheres, mainly composed of carbon, had active groups such as hydroxyl and carboxyl on their surfaces and had good water solubility and lipid solubility. SRC-NCs can effectively adsorb various compounds in mainstream smoke, particularly benzo[a]pyrene, exhibiting adsorption performance superior to that of activated carbon and cellulose acetate-a commonly used material in cigarette filters. It holds promise as a potential substitute for cellulose acetate.
Industrial dust pollution threatens occupational health and production safety, driving the urgent need for optimized filtration technology. Filter plate geometry critically regulates flow fields, filtration performance, and energy consumption. This study numerically modeled a dust collector with a flat filter plate and three corrugated filter plates of different curvatures (lambda = 1/8, 2/8, 3/8). Using the SST k-omega turbulence model, discrete phase model, and JKR adhesion theory, the effects of curvature on flow distribution, turbulent kinetic energy, pressure field, and dust deposition were investigated. Quantitatively, compared with the flat plate (lambda = 0), the corrugated plate with lambda = 1/8 reduces the pressure drop by 3.5% (from 256.4 Pa to 247.3 Pa) by increasing the effective filtration area. Further increasing curvature to lambda = 3/8 significantly improves deposition uniformity and suppresses local filter cake accumulation, though a slight pressure drop rebound occurs due to intensified flow separation. Mechanistically, curvature induces periodic pressure fluctuations and multi-peak turbulent kinetic energy, enhancing particle migration while balancing airflow uniformity. These results demonstrate that the optimal curvature range for balancing energy consumption and deposition performance is lambda = 2/8-3/8.
This work employs direct numerical simulations based on the smooth profile method (SPM) to explore the gravitational settling behavior of bidisperse suspensions composed of non-spherical particles. Rod-shaped particles were modeled as chains of three connected spheres, whereas disk-shaped particles were constructed from seven smaller spheres. Both particle types settled in a Newtonian fluid within the Stokes regime. The study focuses on how varying the proportion of disks relative to rods influences the dynamics, while the overall solid volume fraction was held constant at phi = 0.07 and the disk volume fraction, phi, ranged between 0.00 and 0.07. The simulations reveal disruption of rod ordering and the emergence of disk clustering. With higher phi, the heights of the first and second peaks decrease, while a tertiary peak emerges and gradually intensifies. Furthermore, the mean settling velocity of the suspension rises as phi increases, accompanied by a reduction in drag. Analysis of the temporal autocorrelation in the vertical direction reveals an initial growth up to phi = 0.035 , followed by a progressive decline. These insights can help guide the design of multiphase flow equipment and improve particle separation processes in chemical, environmental, and energy industries.
Two types or operating modes of gas-liquid-solod three-phase flow reactors, slurry bed and fluidized bed, are widely used in chemical industry. Early they were distinguished by the size and density of solid particles and the distribution of axial solid holdup. With the development of modern multiphase flow measurement technology and the requirement of chemical reaction to control multiphase flow more accurately, it is necessary to study the classification of multiphase flow reactors more carefully. In this paper, acceleration vibration signal detection and telecentric photography are used to study the classification criteria of reactor types. The acceleration vibration time series signals at different axial positions of the three-phase reactor are measured by high-precision acceleration sensors and their standard deviation and power spectral density (PSD) are analyzed. Combined the telecentric image visualization results, the operating modes and their transitions are identified and confirmed, and the fine classification criterion of the two operation modes is obtained. When the superficial liquid velocity is 0.01 m/s and no gas is input, the transition boundary between liquid-solid slurry-like bed and fluidized bed is particle size 150 mesh (100 mu m); when the superficial liquid velocity is 0.01 m/s and the superficial gas velocity is 0.0033 m/s, the transition boundary between slurry bed and fluidized bed is particle size 80 mesh (180 mu m). These findings provide useful guidance for the accurate control of three-phase flows and reactions.
Rotary drying and calcination are essential to global manufacturing but remain among the most energy-intensive industrial operations. Due to limited understanding of internal bed dynamics, these processes are often operated at reduced throughput to maintain product quality. Distinct flow regimes arise, including the slipping regime, characterized by particles slipping at the wall, and the rolling regime, in which particle mixing is enhanced. In this work, discrete element method (DEM) simulations are used to investigate the influence of flow regime on heat transfer and mixing in a rotary drum. The flow regime is varied by adjusting wall friction, fill level, rotation rate, and particle properties. Results show that a particle bed in the rolling regime heats approximately twice as fast and achieves about five times greater temperature uniformity than in the slipping regime. Consequently, achieving equivalent product quality in the slipping regime would require roughly a twofold reduction in throughput. Introducing a baffle in the slipping regime induces behavior consistent with the rolling regime, significantly improving heat transfer and throughput. These findings provide a predictive framework for heat transfer in rotary drums, enabling operation at higher throughput with reduced energy consumption while maintaining product quality.
Coal and gas outbursts remain a major threat to coal mine safety, and cryogenic freezing technology presents an effective approach to controlling such incidents. To explore the feasibility of cryogenic freezing technology for outburst prevention, this research examines how low-temperature conditions influence the gas expansion energy of anthracite coals with varying added moisture contents through laboratory experiments. The research findings indicate that low-temperature environments can effectively suppress gas desorption in anthracite coals with added moisture. Gas desorption decreases with lower temperatures and higher added moisture content. The low-temperature conditions slow down methane molecules' thermal mobility and promote the condensation of moisture in pores into ice, thereby blocking gas diffusion pathways and consequently controlling gas expansion energy. The results demonstrate that lower temperatures and higher moisture content lead to a reduction in gas expansion energy. For instance, at 3% moisture content, reducing the temperature from -10 to -30 degrees C caused a 29.50% drop in gas expansion energy. Similarly, at a temperature of -30 degrees C, increasing the moisture content from 0% to 3% results in a 66.32% reduction in gas expansion energy. These outcomes offer theoretical support for applying cryogenic freezing technology in outburst prevention.
This work reports the synthesis and characterization of a rare-earth composite (Nd-0.Pr-8(0).(2))(2)O-3/(Nd-0.Pr-8(0).(2))FeO3, obtained from end-of-life NdFeB magnets through an acid leaching route followed by controlled precipitation and thermal calcination. The developed process enabled the efficient recovery of neodymium, praseodymium, and iron in reactive forms, with high Nd/Pr recovery yields relative to the original magnet composition, highlighting the potential of the proposed route for applications aligned with circular economy principles. Compared to conventional recycling methods, such as pyrometallurgy and solvent extraction, the adopted strategy exhibits lower operational complexity, significantly reduced processing temperatures, and lower energy consumption, while avoiding the extensive use of high-impact organic solvents. Structural analysis by X-ray diffraction (XRD) combined with Rietveld refinement confirmed the formation of a biphasic crystalline system composed of a mixed orthorhombic perovskite and a cubic rare-earth oxide solid solution, with well-defined interfaces and evidence of partial Pr & sup3;(+) incorporation into Nd & sup3;(+) sublattices. Scanning electron microscopy (SEM) revealed a hierarchical and porous morphology, which is favorable for optical and catalytic-related processes. UV-Vis spectroscopy showed broad absorption in the 200-800 nm range, with two direct optical band gaps (1.8 and 3.1 eV) and an Urbach energy of 120 meV, indicating a moderate degree of structural disorder and efficient interfacial electronic coupling between the phases. Magnetic measurements revealed a hybrid magnetic behavior, with
Efficient sedimentation of coal slime water (CSW) is essential for the recycling of washing water in coal preparation plants. Polyaluminum titanium chloride (PATC) was synthesized from AlCl3 & centerdot;6H2O and TiCl4. Coagulation experiments showed that the optimal preparation conditions for PATC were a Ti/Al molar ratio of 1:5 and a basicity (B value) of 0.4. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis indicated that PATC was an Al-Ti polymer composed of titanium and aluminum, with the formation of Ti-O-Al bonds and bridging by hydroxyl groups. For CSW with a mass concentration of 40 g/L, PATC alone requires a lower dosage and exhibits better coagulation performance when used alone. When combined with cationic polyacrylamide (CPAM), PATC reduces the CPAM consumption by 25% compared with polyaluminum chloride (PAC), AlCl3, and CaCl2. After PATC addition, the overall Turbiscan Stability Index (TSI) of the CSW system reached 21.4, which was 2.12, 3.51, and 26.75 times higher than those of PAC, AlCl3, and CaCl2, respectively. Under the action of PATC, the absolute zeta potential of the coal slime particles was reduced to 5.9 mV. The resulting flocs exhibited large particle sizes and compact structures, leading to excellent sedimentation performance.
During automated handling of poplar seeds for phenotypic measurement, an improperly designed or operated air conveying system can lead to reduced efficiency, choking, and batch-to-batch cross-contamination due to incomplete discharge. To address the lack of discrete element method (EDEM) parameters for poplar seeds, three cultivars (Populus pseudo-simonii, Populus & times; euramericana CL. 'Zhonglin46', and Populus deltoides & times; P. euramericana cv. 'Nanlin895 ') were selected for parameter calibration, providing the input required for conducting computational optimization, as traditional experimental methods are insufficient to reveal the underlying particle flow mechanisms. Physical experiments determined the coefficients of restitution (0.489, 0.428, and 0.391), static friction (0.462, 0.503, and 0.564), and rolling friction (0.141, 0.177, and 0.256) against an acrylic plate. The Steepest Ascent Test and Central Composite Rotatable Design were employed to develop Response Surface Models and optimize simulation parameters, yielding optimal inter-particle coefficients, including restitution (0.302, 0.564, and 0.563), static friction (0.540, 0.495, and 0.684), and rolling friction (0.218, 0.184, and 0.154). Validation yielded relative errors of 0.94%, 2.21%, and 2.92% between simulated and actual angles of repose, respectively. The calibrated parameters enable reliable simulation of millimetre-sized seed handling, supporting the development of automated phenotyping systems.
A sustainable, biologically inspired strategy was developed for fabricating multifunctional nanocomposites by biosynthesizing zinc oxide nanoparticles (ZnO NPs) using Amaranthus polygonoides L. leaf extract and integrating them onto graphene oxide (GO) sheets. UV-visible analysis recognized the absorption peaks of GO and ZnO NPs. X-ray diffraction (XRD) pattern showed the crystalline nature of GO-ZnO composite. Fourier transform infrared (FT-IR) analysis revealed the important functional groups within the GO-ZnO structure. Scanning electron microscopy (SEM) elucidated the rectangular-needle-like morphology of ZnO NPs and layered structure of GO. Moreover, energy dispersive X-ray (EDX) and mapping analysis exhibited the elemental presence in synthesized materials. The principal finding of this work is the development of a biosynthesized GO-ZnO hybrid system that exhibits synergistic antifungal functionality and scalable environmental sustainability. GO-ZnO achieved complete inhibition of Fusarium oxysporum in chili plants at 1000 & micro;g/mL and provided effective postharvest protection for tomatoes at 250 & micro;g/mL, while maintaining fruit quality and minimizing physiological weight loss. Moreover, GO-ZnO demonstrated broad-spectrum inhibitory activity against diverse phytopathogens at 100 & micro;g/mL, underscoring its versatility across multiple biological systems. By uniting green synthesis, nanoscale engineering and biological applications, the GO-ZnO shows significant potential as a bio-nano control agent for the sustainable agricultural sector.
Grain bulk materials exhibit complex dynamic responses under dynamic loading such as earthquake. Investigating its dynamic characteristics is critical for the modeling and analysis of the dynamic response of silo system. This study employed a series of stress-controlled dynamic triaxial tests to systematically investigate the effects of confining pressure (50 kPa, 100 kPa, 150 kPa, and 200 kPa) and loading frequency (1 Hz, 1.5 Hz, and 2 Hz) on the dynamic characteristics of wheat bulk materials. The effects of confining pressure and loading frequency on the dynamic elastic modulus and damping ratio are analyzed. Additionally, a comparison of dynamic characteristics between soybean and wheat is conducted. The results indicate that the dynamic stress-strain relationship of wheat exhibits pronounced nonlinearity and hysteresis, which can be effectively characterized by the Hardin-Drnevich (H-D) model. Dynamic elastic modulus increases with increasing confining pressure and frequency, and decreases with increasing dynamic strain amplitude. The damping ratio increases nonlinearly with the dynamic strain amplitude and eventually stabilizes, while it decreases with increasing confining pressure. As a comparison, wheat demonstrates greater stiffness and energy dissipation than soybean, and its dynamic elastic modulus is more confining pressure-sensitive.
Cyclones are separation devices widely used in industry, but the separation efficiency for fine particles with sizes less than 2 & micro;m is not very high. In this paper, a self-circulation cyclone (SCC) for fine-particle separation is proposed and the performance of the new cyclone is evaluated using numerical simulation methods. The SCC includes a traditional cyclone (TC), and a flow separator and a circulating pipe to return the flow with relatively high particle concentration from the gas outlet to the particle bin of the TC. In the present study, the Reynolds number of cyclone inlet was varied from 3825 to 7650. The validity of the computational fluid dynamic (CFD) method using the Euler-Lagrangian model and Reynolds stress model (RSM) was verified by comparing with the experimental datas of the TC that provides the velocity distribution, pressure loss and particle separation efficiency. As a result, the separation efficiency of 1 & micro;m particles was 28% for the TC and 68% for the SCC with D = 300 mm cylinder diameter. Meanwhile, the pressure loss in the SCC at the same scale increased by 25% on average than that of the TC. However, the overall results showed the effectiveness of the SCC for fine particle separation.
