Particuology

The dataset is the measurement of wall adhesion tensile stress between iron ore materials and wall surfaces.

The bonded-particle model (BPM) is commonly used in the numerical analysis of ore samples. To improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher, the parameters of the BPM for the ore must be calibrated. In this study, a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial compression. First, physical tests and simulations were conducted to determine the mechanical response (uniaxial compressive strength and macroscopic stiffness) of ore during uniaxial compression. Then, the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett‒Burman design. Next, the microscopic parameters with the greatest impact on the response were identified, and the range of parameters that met the target response was determined using a steepest ascent design; Second, a second-order model of the mechanical response was established using the sensitive parameters by combining a Box‒Behnken design with response surface methodology to obtain the optimal BPM parameters. Simulation tests showed that the normal stiffness per unit area, critical shear stress, and bonded disk radius had significant effects on the uniaxial compressive strength (UCS) and macroscopic stiffness (MS). To verify the validity of the proposed calibration method, laboratory tests were conducted. The consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett‒Burman design, steepest ascent design, and Box‒Behnken design can be an effective method for calibrating the BPM of ores.

Due to the typical intercalation-deintercalation mechanism, TiO2 holds great promise as a sustainable anode for next-generation lithium-ion batteries (LIBs). However, commercial TiO2 (C–TiO2) is granular and shows slow ionic conductivity, which greatly hinders its development due to sluggish kinetics, leading to low reversible capacity and inferior rate capability. In this study, a two-dimensional layered TiO2 (L-TiO2) anode is prepared via a one-step calcination process, which can effectively shorten the lithium ions diffusion path and improve its lithium ions conductivity. We elucidated the enhanced electrochemical performance of L-TiO2 as an anode in LIBs through pseudocapacitive acceleration of lithium ions intercalation and deintercalation using various characterization techniques, including different scan rate cyclic voltammetry tests, in situ electrochemical impedance spectroscopy, in situ Raman spectroscopy, and in situ X-ray diffraction. In comparison to C–TiO2 material, L-TiO2 material showcases remarkable electrochemical performance, achieving a capacity of 166 mAh/g after 100 cycles at 0.1 C. Additionally, the lithium-ion diffusion coefficient calculated for the L-TiO2 is two orders of magnitude greater, underscoring its potential as a negative electrode material for LIBs.

This study aims to analyze the coking process and propose an effective method for the reutilization of fluid catalytic cracking (FCC) coke block. Herein, we analyzed the basic characteristics and chemical composition of FCC coke blocks. The results showed that the main components were carbon, oxygen, and aluminum, accounting for 60.8%, 26.6%, and 11.5%, respectively. Under the conventional catalytic cracking reaction temperature from 500 °C to 600 °C, the formation of the first aromatic hydrocarbon was particularly important for the formation of coke. The condensation of oil-gas-entrained catalyst particles and their heavy components was the physical cause of coking, while the dehydrogenation condensation reaction of oil-gas heavy components was the chemical factor. In addition, the membrane prepared by powdered coke had excellent photothermal conversion ability, which could be heated to more than 110 °C within 360 s under two fixed light intensities. The evaporation rate of photothermal water was 5.89 kg m2 h−1, which has great industrial application potential. These works provide a novel and effective method of separation membrane for the reutilization of FCC coke blocks.

The fast and accurate reduced-order modeling of fluidized beds is a challenging task in the field of fluid dynamics, owing to their high dimensionality and nonlinear dynamic behavior. In this study, a nonintrusive reduced order modeling method, the reduced order model based on principal component analysis and bidirectional long short-term memory networks (PBLSTM ROM), was developed to capture complex spatio-temporal dynamics of fluidized beds. By combining principal component analysis and Bidirectional long- short-term memory networks, the PBLSTM ROM effectively extracted dynamic evolution information without any prior knowledge of governing equations, enabling reduced-order modeling of unsteady flow fields. The PBLSTM ROM was validated using the solid volume fraction and gas velocity flow fields of a fluidized bed with immersed tubes, showing superior performance over both the PLSTM and PANN ROMs in accurately capturing temporal changes in the fluidization fields, especially in the region near immersed tubes where severe fluctuations appear. Moreover, the PBLSTM ROM improved the simulation speed by five orders of magnitude compared to traditional computational fluid dynamics simulations. These findings suggest that the PBLSTM ROM presents a promising approach for analyzing the complex fluid flows in engineering practice.

Baicalin (BA) is a flavonoid extracted from the dried root of Scutellaria baicalensis Georgi with excellent antioxidant and anti-inflammatory biological activities. In this study, Eudragit S100 was used as the colonic target material to prepare BA colonic targeting granules (EBCGs) based on plasticizer dry powder coating technology to improve the targeting transportation performance of BA. In vitro studies showed that EBCGs with pH-sensitive properties were successfully prepared by plasticizer dry powder coating, and in vivo animal imaging studies showed that EBCGs could deliver BA to the colon and inhibit the release of BA in the upper gastrointestinal tract (GIT). In vivo studies showed that EBCGs had good therapeutic effects in colitis, which reduced expression levels of tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) and increased superoxide dismutase (SOD) activities in the colonic tissues of rats with colitis. In conclusion, Eudragit S100 could be used for the preparation of multi-unit oral colon-targeted formulations by plasticizer dry powder coating technology, and our prepared EBCGs had good colon-targeting properties, which could improve the therapeutic effect and provide a potential application for ulcerative colitis (UC).

Voidage (porosity or void fraction) in packed particles (or pebbles) is of fundamental importance in calculating the pressure drop, obtaining the drag, predicting the bed permeability, estimating the neutron streaming, etc. For the case when particles are deformed, a method of voidage correction during the packing state is proposed using a Discrete Element Method (DEM) simulation of 3D pebble flow inside a bed of cycloidal base. A function to evaluate the remaining volume of a pebble intercepted by horizontal and vertical planes is proposed for voidage calculation. After that, the process of solving voidage distribution is provided in detail. Using this method, the voidage inside the cycloidal-base pebble bed is obtained to refer to reported similar data for validation. This method can be potentially used for dynamical voidage calculation in CFD-DEM simulation which can get suitable voidage distribution after the correction.

A high-pressure laser ignition and combustion system with adjustable oxidizer gas atmosphere is established to investigate the ignition and combustion characteristics of boron-magnesium (BM) composite powders. An ignition and combustion model of BM powders is established and validated in the present study. The results show that increasing water content, O2 content and Mg content all result in shorter ignition delay time of BM powders, among which the effect of water content is the most obvious. However, ignition delay time increases as pressure increases. The combustion time decreases with increasing Mg content and ambient pressure but increases with water content. With the increase of O2 content, combustion time of BM powders first increases and then decreases, which means a critical O2 content exists above which combustion time decreases. The results show that there exists a trade-off between ignition and combustion performance of BM composite powders.

A novel triaxial vibration method is developed for the real-time characterization of the solid particle size distribution (PSD) in pneumatic particulate flow, which is critical for chemical industry. In this work, the particle‒wall collision and friction behaviours were analysed by the time-domain statistical and time-frequency joint methods to narrow the high-frequency response range by the initial experiment of free fall for a single particle, interparticle, and multiple particles. Subsequently, verification experiments of PSD characterization in pneumatic flow were performed. First, the quantitative triaxial energy response model that considers the particle size, shape, and mass factors were established. Second, a good agreement of the particle number identification was found between the triaxial vibration energy and mean particle size of 150–550 μm. Moreover, the performance with the best accuracy was focused on a range of 42–43 kHz in the x-axis and z-axis and 36.8–38.8 kHz in the y-axis. Finally, the individual particle energy was inversely analysed by the triaxial vibration response within the optimized frequency bands, and the PSD was characterized in real-time by a low error rate, that is, 5.2% from the XZ-axis direction of sand (42–43 kHz) and 5.6% from the XYZ-axis of glass (30.9–33.9 kHz, 46.2–47.2 kHz, 38.3–41.3 kHz for each axis response). Therefore, this research complements the existing approaches for PSD characterization in particulate multiphase flow.

This paper investigates the impact of flue gas desulfurization (FGD) gypsum's crystal modifier on the characteristics and microcosmic mechanism of α-high strength gypsum. The results demonstrate that all three crystal modifiers can convert FGD gypsum to α-high-strength gypsum. Citric acid (CA) has the most significant influence on α-high-strength gypsum, and the prepared α-high-strength gypsum is short columnar, with an aspect ratio in the range of 1–3, and has a faster setting time, a larger specific surface area, and a smaller standard consistency, higher compressive strength, greater surface hardness, and smaller crystal particle size. The initial setting time of the α-high-strength gypsum manufactured with CA crystal modifier was decreased by 36% compared to the blank sample, the final setting time was lowered by 37.5%, and the water consumption of the standard consistency was reduced by 8%. The maximum strength is 32 MPa after 2 h, the absolute dry compressive strength is up to 38 MPa, and the surface hardness is improved by 24.43%.