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To address the issues of low curing depth and high viscosity in VPP slurries caused by the high refractive index and hydrophilic surface of silicon nitride (Si 3 N 4), this study proposes a novel surface modification method. The process starts with the pre-coating of Si 3 N 4 powder using the silane coupling agent KH570. This is followed by an oxidation step that forms a uniform SiO 2 layer on the powder surface, effectively reducing the refractive index mismatch between Si 3 N 4 and the resin, as well as minimizing light scattering. The KH570 pre-coating also protects the Si 3 N 4 lattice, mitigating oxidation-induced damage and preserving structural integrity. Subsequently, the Si 3 N 4 powder undergoes further modification with the silane coupling agent KH560 to enhance the slurry's flowability and stability. Using this three-step method of pre-coating, oxidation, and surface modification, a Si 3 N 4 slurry with 45 vol% solid content was successfully prepared. The slurry's viscosity decreased by 20–30 %, and under a laser power of 1200 mW, the curing depth increased by 52.9 %, reaching a value of 192.7 μm with a viscosity of 7.69 Pa s (at a shear rate of 30 s⁻1 and 47.8 rpm). This approach enables the fabrication of high-quality Si 3 N 4 ceramic components with intricate geometries. [ABSTRACT FROM AUTHOR]

When preparing aluminum oxynitride (AlON) transparent ceramics from Al 2 O 3 -AlN slurries by direct ink writing (DIW), green bodies need long drying duration to guarantee uniform water evaporation but AlN hydration will happen, creating extra alumina content and deteriorating the optical properties of AlON. Being capable of dissolving a portion of Al 2 O 3 , MgAl 2 O 4 was doped to prepare AlON transparent ceramics through reactive sintering using DIW technology. With 79 wt% solid-content aqueous slurries, AlON gradually becomes single phase with densities around 3.69 g/cm3 after MgAl 2 O 4 content and sintering temperature regulating, resulting in a substantial enhancement in optical transmittance. Through transmission electron microscopy analysis, MgAl 2 O 4 helps reduce the internal stress in AlON lattice, diminishing lattice distortion and enhancing transmittance. However, MgAl 2 O 4 addition also results in grain size increase and decreases mechanical properties of AlON. This study provides a new approach to solve AlN hydration when preparing AlON transparent ceramics by DIW from Al 2 O 3 -AlN aqueous slurries. [ABSTRACT FROM AUTHOR]

As one of the most widely used technologies in ceramic additive manufacturing, digital light processing (DLP) enables the precise formation of ceramic products with complex structures. Current studies on Si 2 N 2 O ceramics are mainly focused on the reactive sintering of Si 2 N 2 O ceramics and the traditional molding and processing processes, and investigations on the DLP of Si 2 N 2 O ceramics are lacking. In this study, Si 2 N 2 O ceramics with complex structures were prepared by DLP. Initially, the effects of the dispersant type and content on the rheology, sedimentation, and curing properties of the Si 2 N 2 O ceramic slurry were investigated. The results revealed that 4 wt% KH570 included as an additive could effectively improve the compatibility between the Si 2 N 2 O powder and resin, imparting good fluidity to the prepared slurry. Furthermore, the UV absorption of the Si 2 N 2 O powder at 450 nm decreased from 0.24 to 0.11, which was conducive for improving the curing properties of the Si 2 N 2 O ceramic slurry. Subsequently, the effects of the sintering additives, holding time, and sintering temperature on the properties of the porous Si 2 N 2 O ceramics were investigated. Finally, a Si 2 N 2 O ceramic slurry with a solid content of 40 vol% was prepared using 5 wt% Al 2 O 3 as a sintering agent. Upon sintering at 1600 °C for 3 h, a Si 2 N 2 O ceramic body with a porosity of 7.26 %, density of 87.54 %, and flexural strength of 207 MPa was obtained. [ABSTRACT FROM AUTHOR]

Bottom vacuum preloading (BVP) is the method of applying vacuum pressure at the bottom zone of soils to generate pore-water pressure difference between the top and bottom boundaries, thereby achieving the consolidation drainage. This study conducted a large-size model test to explore the engineering feasibility of combining self-weight and BVP to treat construction waste slurry (CWS). Through the treatment of the measures of self-weight consolidation (0–26 d) and BVP with a water cover (26–78 d), the average water content of CWS declined from 255.6% to 115.9%, and the volume reduction ratio reached 0.476. However, since these two measures could properly treat only the bottom CWS, the measures of BVP with the mud cover (78–141 d) and the natural air-drying (141–434 d) were performed to further decrease the CWS water content near the upper zone. The latter two-stage measures reduced the average water content of CWS to 84.9% and increased the volume reduction ratio to 0.581. Moreover, the measurements suggested that the treated CWS largely exhibited a shear strength of 10 kPa or more. Overall, the proposed approach appeared some engineering feasibility to treat CWS, and the performed test study could act as a reference for the practical treatment of CWS. • Treatment mechanisms of CWS under self-weight and BVP were introduced in detail. • A first large-size model test for treating CWS under self-weight and BVP was conducted. • Total volume reduction ratio of CWS had reached 0.581 after the large-size model test. • Treatment method of combining self-weight and BVP exhibited some engineering feasibility. [ABSTRACT FROM AUTHOR]

Suction stress, the part of effective stress induced by soil–water interaction, is the source for the intrinsic cohesion of fine-grained soil slurries. Here, the previous unified effective stress equation is generalized to extend the suction stress variation from the liquid state to the oven-dry state, yielding an augmented closed-form equation. This equation includes a new term, named slurry adsorptive suction stress, to incorporate the adsorptive mechanism of soil slurries at the liquid state. This adsorption mechanism involves the interparticle van der Waals attraction, face-to-edge attraction, and electrical double-layer repulsion when soils are in the liquid state. The proposed equation is validated with a wide array of 12 fine-grained soils' shrinkage curves, modulus, and suction stress data measured by the drying cake test. It is demonstrated that the proposed equation can excellently capture the experimental data across all saturations. Furthermore, the practical implications of the proposed model are illustrated via its relevance to rheological properties of soil slurries and correlations with both liquid limit and plastic limit. [ABSTRACT FROM AUTHOR]

The forced oxidation of sulfite ions was conducted to obtain high-quality gypsum in the flue gas desulfurization system. The effects of formic, lactic, acrylic, acetic, propionic, and hexanoic acids added to calcium-based slurry on sulfite oxidation were investigated in this study. Sulfite oxidation was inhibited when the pKa value of organic acids was small or the carbon chain was long. In the identical slurry pH 6, the SO42- fractions of slurries with formic and lactic acids, which have the smallest pKa values, were lower than half that of the additive-free slurry. The addition of hexanoic acid with the longest carbon chain showed a similar SO42- fraction to that of additive-free slurry. These results indicate that the inhibitory effect on sulfite oxidation is more expressed by the acidity of organic acids. The SO42- fraction in the slurry affects the growth and quality of gypsum crystals. The slurry with acetic acid presented the highest SO42- fraction and resulted in the formation of high-quality gypsum crystals. The findings of this study can contribute to the selection of organic acid additives with high desulfurization efficiency and the production of high-quality gypsum. [ABSTRACT FROM AUTHOR]

As an effective reinforcement technology for seepage prevention, penetration grouting has been widely used in geotechnical and underground engineering. Because grouting is a hidden project, the extent of slurry spread is often estimated theoretically and through experience. Therefore, it is important to understand the diffusion pattern and scope of penetration grouting in reinforcement engineering. Based on the generalized Darcy's law, a penetration grouting model considering the gravity and the time-varying nature of the slurry viscosity is proposed in this study. Its validity and effectiveness are verified through a comparison with existing penetration grouting tests. Based on the established penetration grouting model, the effects of the grouting pressure, permeability coefficient, water–cement ratio, and other factors on penetration grouting are analyzed. The penetration and diffusion process of a Bingham fluid considering gravity and time-variable slurry viscosity is computationally simulated using a finite-element software. The research results show that the proposed penetration grouting model is more accurate than the traditional one that does not consider the two aforementioned factors, and its results are more in line with the experimental ones. The rate of error calculated from the experimental value is about 11%. The diffusion radius of the slurry increases with increasing grouting pressure, permeability coefficient, and water–cement ratio, and decreases with increasing groundwater pressure. With the elapse of the grouting time, the increase rate of the diffusion radius exhibits a trend of increasing first and then decreasing and tending to level off. These research results can provide certain theoretical support for penetration grouting research in geotechnical and underground engineering. [ABSTRACT FROM AUTHOR]

Borehole wall stability is the key to the shield tunnel and horizontal directional drilling (HDD) under a sand-pebble layer. Borehole instability will lead to the collapse of the upper ground and damage to adjacent structures. To improve the stability of transportation in highly permeable formations, it is suggested that quartz sand be added to the silicate membrane. Here, different particle sizes (40, 70, 120 mesh) and contents (1%, 2%, 3%, and 4%) of quartz sand were applied to investigate the influence of quartz sand on the properties of silicate slurry and filter cake performance by analyzing the rheological properties, fluid loss, and filter cake properties. The results show that when the particle size is 120 mesh and the content is 2% in the membrane slurry, the quartz sand effectively promotes the filter cake performance. Moreover, the spatial structure formed in the slurry is continuous, and the viscosity, static shear force, dynamic shear force, and flow index of the slurry are within an appropriate range, indicating that silicate slurry with 120 mesh and 2% content quartz sand can make the slurry perform well in the sand-pebble layer. This formulation facilitates the effective formation of the filter cake, reduces fluid loss volume, and maintains borehole stability. [ABSTRACT FROM AUTHOR]

The pressurised bentonite slurry efficiently stabilised the tunnel face, but slurry infiltration may reduce its effectiveness. In this work, the effect of slurry infiltration on tunnel face stability during slurry-shield tunnelling in saturated cohesionless soil is investigated, and the results reveal that due to slurry infiltration, an additional margin for support pressure is needed. The infiltration distance has a significant influence on the effective support at the tunnel face. For slurries with a low viscosity (apparent viscosity = 4 mPa·s), only when the infiltration distance is small (< 0.5 m) is the effective support ratio high (> 80%). Furthermore, a larger infiltration distance or a larger value of tunnel diameter to cover depth ratio (C/D) requires a higher support pressure. Generally, the hydraulic gradient at the face in an unconfined aquifer is greater than that in a semi-confined aquifer. For semi-confined aquifer, a smaller height or a larger leakage length leads to a greater hydraulic gradient. Finally, for shield tunnelling in an aquifer, when the gradient at the tunnel face is less than 1, a viscous slurry is recommended to replace the pure water to support the tunnel face. [ABSTRACT FROM AUTHOR]

The process of planar devices is approaching its physical limit, and through-silicon via (TSV) technology is the core of 3D integration technology that breaks Moore's law and has a competitive advantage. Chemical mechanical polishing (CMP) is a key process for removing excess copper in the TSV process. The composition of TSV copper film slurry is very important for achieving TSV wafer planarization. At the same time, as the slurry is a disposable product, the cost of copper polishing is relatively high, so the research and development of TSV copper film slurry has become a hot topic. This article reviews the research progress of TSV copper slurries both domestically and internationally from the perspective of improving the surface quality and polishing rate of copper polishing, as well as regulating the removal rate selection ratio of copper and barrier layer materials. It also predicts the future development direction of TSV copper film slurries. It is believed that TSV copper film slurries should be developed based on faster copper polishing rates, controllable copper and barrier layer polishing rate selection ratios, higher polishing quality, lower costs, and lower pollution with less environmental impact. [ABSTRACT FROM AUTHOR]

This study investigates the impact of various solvents on the static stability and flow characteristics of waste-activated carbon (WAC)-based coal-water slurry for co-gasification. Using the Euler–Euler method, we analyze slurry stability both in stationary conditions and during flow in a horizontal pipeline. Results show that glycerin offers the highest stability during slurry preparation, while acetonitrile provides the lowest. Solvents like glycerin, propanol, and formamide improve stability compared to water. In static conditions, glycerin’s stable height change rate is nearly 0, while acetonitrile peaks at 4.09. During the flow, glycerin-based slurry maintains a stable height of 40 mm with no accumulation, while acetonitrile retains only 88% of its height. The solid volume fraction difference for glycerin slurry is minimal (0.011), whereas acetonitrile slurry shows a much larger difference (0.7). However, glycerin slurry has the highest pressure drop (129 mWc/100 m), indicating higher energy consumption during transportation. This study highlights how solvent viscosity and density influence slurry properties and introduces a numerical approach for predicting slurry stability in preparation and transport. [ABSTRACT FROM AUTHOR]

Chemical mechanical polishing (CMP) offers promising pathway to smooth 4H-SiC. Dispersion stability of polishing slurry is crucial factor affecting 4H-SiC performance. Particles in polishing slurry can easily agglomerate due to poor dispersion stability, affecting surface quality of wafers. Nano-Al 2 O 3 is common particle in the slurry that directly controls mechanical removal. In this paper, the impact of different dispersants (PEG, (NaPO 3) 6 , and NH 4 PAA) on the dispersibility of slurry containing nano-Al 2 O 3 is studied. Results indicate that the slurry containing NH 4 PAA exhibits the greatest dispersion stability with superior 4H-SiC surface quality, with surface roughness (Sa) reaching 1.054 nm. The slurry containing PEG shows poor dispersion, leading to poor SiC surface quality, and the Sa reached 5.314 nm. The dispersion mechanism of different dispersants is also discussed. [ABSTRACT FROM AUTHOR]

This study investigates the rheological behavior of oil well cement pastes (OWCPs) modified with core/shell TiO2@SiO2 (nTS) nanoparticles and polycarboxylate-ether (PCE) superplasticizers at different temperatures (25, 45, and 60 °C). Results show that nTS particles increased static and dynamic yield stresses and the apparent viscosity of the cement slurries due to an increased solid volume fraction and reduced free water availability. The increase in the slurry dispersion by adding PCE superplasticizers enhanced the effect of the nanoparticles on the rheological parameters. Oscillation rheometry demonstrated that nTS nanoparticles enhanced the structural buildup, while PCE retarded hydration. Furthermore, slurries hydrated at 60 °C experienced higher initial values of the elastic modulus and a faster exponential increase in this rheological parameter due to the acceleration of the cement hydration. [ABSTRACT FROM AUTHOR]

Slurry infiltration method has been widely used as a preliminary step in preparing dense and multifunctional fiber reinforced SiC ceramic matrix composites. However, the infiltration efficiency of slurry is low mainly due to its insufficient stability, specifically manifested as the limited weight gain of composite after slurry infiltration. The aim of this study is to improve the infiltration efficiency of slurry by improving its stability, while maintaining its low viscosity and high particle concentration. In this study, by adjusting the particle size, two SiC slurries with identical high particle concentration (50 wt.%) and similar low viscosities (less than 10 mPa·s) but different stabilities were obtained and then applied in the infiltration process of composites. The stability of slurry can be highly improved by decreasing the particle size. The weight gain of composites after infiltration of high stability slurry (sedimentation time exceeding 35 h) is more than twice that of low stability slurry (sedimentation time nearly 1 h). Combined with chemical vapor infiltration method, the final composite using high stability slurry exhibits increased density, reduced porosity and enhanced mechanical performance. [ABSTRACT FROM AUTHOR]

The use of submicron silicon carbide powder as a raw material is crucial for preparing high-performance silicon carbide ceramics. However, its strong absorption of ultraviolet light makes stereolithography of submicron silicon carbide powder challenging. In this study, submicron SiC particles, photosensitive resin, and photoinitiator were used as raw materials to prepare SiC ceramics via stereolithography combined with a pressureless sintering method. The effects of ultraviolet wavelength, type, and content of photoinitiator on the curing properties of submicron SiC ceramic slurry were investigated. The results showed that the curing thickness of the SiC ceramic slurry significantly increased with the increasing ultraviolet wavelength. Compared to photoinitiators TPO and 396, photoinitiator 819 exhibited a better curing effect. Additionally, increasing the photoinitiator content facilitated the generation of more free radicals in the SiC ceramic slurry at low light intensity, thereby improving its ultraviolet absorption characteristics. When the dosage of photoinitiator 819 was 8.8 %, the SiC slurry achieved the best curing performance, with a single-layer curing thickness of 50 μm and a sintering density of 95 % for SiC ceramics. [ABSTRACT FROM AUTHOR]

Pig slurry can be used as an alternative source for nutrients, particularly nitrogen (N), for plants. However, after applying the pig slurry to the soil, gaseous loss of N this nutrient may occur, mainly in the form of ammonia. Hence this study aimed to evaluate the loss of N by volatilization after the application of pig slurry with an acidified pH. Ammonia volatilization was evaluated using pig slurry, with its pH modified to 5.0 using four acids (sulfuric acid, citric acid, ascorbic acid, and acetic acid). Additionally, pig slurry with natural pH and a control were also used. The work was conducted in a greenhouse, and collectors were used to capture the volatilized ammonia in a static free semi-open chamber. The application of pig slurry with natural pH (7.19) resulted in 61% loss of ammonia, whereas acidification with ascorbic acid (pH 5.0) caused a loss of only 26%. The application of pig slurry with pH above 7.0 caused N loss, indicating that using acids to maintain a pH of 5.0–6.0 could be an alternative to reduce N loss by ammonia volatilization. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the rheological and compression behavior of cement-solidified dredged slurry with varying rice straw fiber contents (0–12%). Laboratory tests, including flow tests, viscosity measurements, and compression tests, were conducted to evaluate the influence of straw fibers on material properties. Results show that the slump flow value increased by 8.4% when fiber content increased from 0% to 0.5%, reaching a peak at 3% fiber content. Beyond 5% fiber content, slump flow decreased due to fiber entanglement and water absorption. The dynamic viscosity initially decreased as straw fibers released glucose, retarding cement hydration, but increased as fiber content surpassed 1%, due to increased water absorption and the formation of a fiber network. Yield shear stress also increased with fiber content, peaking at 5% fiber content, and was higher in fiber-reinforced slurries compared to non-fiber mixtures. Compression tests revealed that the compressibility of the solidified slurry increased with higher fiber content at early curing stages (28 days) but decreased with longer curing times (90–180 days). Compression yield stress increased initially with fiber content up to 1% but declined beyond this threshold due to fiber-induced porosity and disrupted cement bonding. [ABSTRACT FROM AUTHOR]

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This study aims to analyze the ceramic-metal composite Al2O3/TiO2/TiAl2O5 obtained using the slip-casting method. Samples containing 50% vol. of the solid phase and 2% vol. and 4% vol. fractions of the metallic phase were examined. Rheological investigations were performed. Measurements of shrinkage and density of the composites produced were determined. The phase composition of the obtained composite was investigated using SEM/EDS and XRD techniques. Stereological analysis was performed as well. The slip-casting method enables the production of the proposed composite, reinforced by the presence of TiO2 and TiAl2O5. With the increase in the content of the metallic phase in the composite, the thialite phase content increases, but relative density and volumetric shrinkage of the obtained composites both decrease. Thialite grains are characterized by a size in the range of 4 µm to 15 µm, which leads to a low density of the samples. The results revealed that no significant effect of changing the metal phase content of the slurries used for the composites being fabricated was observed on the limiting grain growth of alumina during the sintering process of slip-casting composites. This finding is important as it suggests that the increase in metallic phase content does not lead to undesirable grain coarsening, which could degrade mechanical properties. [ABSTRACT FROM AUTHOR]

The formation of geotechnical structures on foundations composed of low-strength soils is associated with a number of risks and difficulties. Soils such as clay-salt slurries are characterized by low bearing capacity and a tendency to deform under load. In this study, a numerical simulation of the stability analysis of an embankment constructed on low-strength soils consisting of clay-salt slurries is carried out, and the study of the dependence of the stability and behavior of the embankment on the configuration of this foundation, without taking into account the embedment of rocks and with introduction of rocks into the geotechnical system, is considered. The results prove that the sloping configuration of low-strength soils greatly complicates the stability of the embankment. It is noted that the stability factor is significantly reduced under the influence of loads on low-strength soil, particularly when the geotechnical system has a configuration with slope angles of 5° and 10°, and, in addition, when rocks are embedded in low-strength soil if the underlying soil layer is a weak foundation. In view of this, the assessment of embankment stability on clay-salt slurries requires careful analysis due to a number of specific characteristics of these soils that create complex geotechnical conditions. [ABSTRACT FROM AUTHOR]

We investigate the shear flow of a sludge mimicking slurries produced by the nuclear industry and constituted of a dispersion of non-Brownian particles into an attractive colloidal dispersion at a total solid volume fraction of about 10 %. Combining rheometry and ultrasound flow imaging, we show that, upon decreasing the shear rate, the flow transitions from a homogeneous shear profile in the bulk to a fully arrested plug-like state with total wall slip, through an oscillatory regime where strong fluctuations of the slip velocity propagate along the vorticity direction. When the shear stress is imposed close to the yield stress, the shear rate presents large, quasi-periodic peaks, associated with the propagation of local stick-and-slip events along the vorticity direction. Such complex dynamics, reminiscent of similar phenomena reported in much denser suspensions, highlight the importance of local flow characterization to fully understand sludge rheology. [ABSTRACT FROM AUTHOR]

Zirconia-toughened alumina (ZTA) powders with 20.0 wt.% of ZrO2 were synthesized using the coprecipitation method. Transmission electron microscopy indicated that the powders contained needle-like particles 15–30 nm long and 50–70 nm flake-like particles with a uniform component distribution. Effects of different Y2O3 concentrations (3.0, 4.0, or 5.0 mol.%) and 0.5 wt.% of MnO on the phase composition, microstructure, and physicomechanical properties of the composites were evaluated after sintering at 1600 °C. The microhardness of 5ZTA-Mn samples (5.0 mol.% of Y2O3 and 0.5 wt.% of MnO) was 1653 ± 50 HV when density reached 4.18 g/cm3. For digital light processing on a commercial 3D printer Anycubic Photon S, acrylate-based homogeneous slurries were obtained. Compositions based on ZTA powder stabilized with 5.0 mol.% of Y2O3 and containing 0.5 wt.% of MnO were studied. MnO in the materials improved polymerization depth during the UV-curing process as compared to 5ZTA materials. The microstructure and mechanical properties of the 5ZTA-Mn composites were investigated at the sintering temperature of 1600 °C. Compared with 5ZTA, the 5ZTA-Mn composites showed higher density (4.0 g/cm3) and microhardness (1409 ± 50 HV). According to in vitro experiments, the newly developed materials are promising for biomedical applications and can serve as a basis for the production of personalized implants via digital light processing printing. [ABSTRACT FROM AUTHOR]

Though the application of photochromic agents onto textile-based surfaces with the help of printing process or padding technique, their usability have been limited due to their low substantivity. In this study, 12 wt% polymer solutions were prepared with use of three different polyvinyl alcohol (PVA) pellets having identical hydrolysis degree but different molecular weights. Electrospinning was performed after addition of 4 wt% photochromic slurry (PCS) into these polymer solutions. Densities of photochromic slurry-loaded polymer solutions were measured and UV-Vis spectrophotometric analysis was performed for each polymer solution. Nanocomposite mats electrospun from these photochromic slurryloaded polymer solutions were characterized by FTIR, FESEM and UV-Vis spectrophotometry analysis in order to observe morphological, structural and photochromic properties. Thickness of these nanocomposite mats were also measured. Increase in polymer molecular weight lead to increase on average fiber diameter and mat thickness but fabrication of large pore-sized mat with high pore size variation. Even the finest nanofiber handling, surface imperfections were observed in nanocomposite mats electrospun from PVA 5-88 having the lowest molecular weight among the studied PVA polymers. PVA 14-88 polymer having moderate molecular weight exhibited optimum characteristic properties due to its appropriate polymer solution density, producibility of nano-scale electrospun fibers, possibility to make a consistent relationship among pore size, nanofiber diameter and photochromic efficiency. When UV-Vis spectrums of PCS loadedpolymer solutions and electrospun mats were compared, electrospinning technique caused to a differentiation in absorbence value, especially in PVA 17-88. [ABSTRACT FROM AUTHOR]

Laponite (LAP) is a promising biomaterial for bone regeneration due to its reliable biocompatibility and excellent osteoinductivity in bone tissue engineering. However, the personalized manufacture of LAP bioceramic scaffolds with controlled complex architecture and high porosity remains challenging. This study used vat photopolymerization (VPP) to manufacture LAP bioceramic scaffolds with high precision and biological activity. We first selected a 40 wt% LAP bioceramic slurry for subsequent VPP printing based on stability experiments and viscosity characterization results. The curing parameters of the photosensitive bioceramic slurry and the degassing sintering process were studied to ensure the quality of the ceramic green bodies. Then, we characterized the effects of different sintering temperatures (1150 °C, 1200 °C, 1250 °C) on the crystalline phase composition, microstructure, and mechanical properties of the LAP bioceramic. The research showed that the densification and compressive strength of the LAP bioceramic sintered at 1250 °C reached 2.51 g/cm3 and 15 Mpa, respectively. Finally, the bioceramic scaffolds with different sintering temperatures were co-cultured with rat bone marrow mesenchymal stem cells to detect biocompatibility. The results showed that the three groups of scaffolds enhanced cell proliferation, adhesion, and osteogenic capacity. In conclusion, the LAP bone scaffolds by VPP presented the potential for bone repair. [ABSTRACT FROM AUTHOR]

CeO 2 nanoparticles have small particle size, quantum size effect and surface effect, which make the particles easy to agglomerate. How to restrain the agglomeration of particles is the key to the preparation of high-quality CeO 2 polishing paste, and it is also a research hotspot in the field of fine powder. Therefore, this study is devoted to using different kinds of surfactants and their additives to improve the dispersion stability of Ce 0.96 Y 0.02 Pr 0.02 O 2 polishing solution and the performance of photocatalysis-assisted chemical mechanical polishing (PCMP), including cationic surfactant (Cetyl trimethyl ammonium bromide, CTAB), anionic surfactant (Sodium dodecyl benzene sulfonate, SDBS) and Nonionic surfactant (Polyvinylpyrrolidone, PVP). The results of dispersion stability show that compared with CTAB and SDBS, the polishing solution containing 2.5 wt% PVP has the advantages of slow settling rate and high absorbance, and the improvement effect of dispersion stability is the best. In addition, the polishing properties of different surfactants in quartz glass photocatalysis-assisted chemical mechanical polishing were analyzed. The polishing solution prepared with PVP as dispersant has lower surface roughness (Ra:0.13 nm). However, it is worth noting that the material removal rate decreases after the addition of surfactant, which may be related to the lubrication of surfactant in polishing slurry. Through the test of the friction coefficient, it can be seen that the introduction of surfactant does reduce the friction coefficient of the polishing slurry, and then affect the improvement of material removal rate. Finally, it is proposed that the dispersion mechanisms of CTAB, SDBS and PVP are electrostatic stability, electrostatic stability and steric hindrance stability, respectively. The dispersion mechanism of different surfactants can provide a theoretical basis for researchers to optimize the polishing process and provide guidance for the selection of suitable surfactants. [ABSTRACT FROM AUTHOR]

Ultrafine tailings exhibit slow settling rates, low thickening efficiency, and high overflow water turbidity, necessitating the use of flocculants to accelerate fine particle sedimentation. However, flocculant residues remain in the thickened paste-like slurry, increasing its viscosity, reducing its concentration, promoting agglomeration, and raising pipeline transport resistance. This study employed theoretical analysis and field experiments to explore the mechanism by which flocculant residue influences the rheological properties of ultrafine ungraded tailings paste-like slurry. Results indicate that under flocculant restoration or shear damage, the floc network structure either encapsulates or releases water molecules, inducing migration and transformation between free and capillary water. This phenomenon is the fundamental cause of changes in the shear rheological properties of ultrafine ungraded tailings paste-like slurry. By optimizing flocculant selection, the study achieved a significant reduction in flocculant dosage and effectively mitigated its adverse effects. The findings hold substantial significance for systematically advancing the theory and methods of paste-like slurry shear rheology and pipeline transport. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP) three‐dimensional printing has the advantages of both high printing resolution and efficiency and has been used to manufacture high‐precision, small, and complex shaped ceramic parts. One of the challenges of DLP is to develop photosensitive ceramic slurries with high solid content and low viscosity, especially for non‐oxide ceramics such as silicon nitride due to the dispersion and light absorption problem. This study mainly explores the dispersibility of silicon nitride in ultraviolet (UV)‐cured resins and the photocured properties of the slurry. Rheological measurements were utilized to characterize and screen different dispersants in the resin. It was found that DISPERMP is an effective dispersant. In order to improve the curing depth of Si3N4 photosensitive paste, the surface of silicon nitride powder was treated by oxidation, and organic compounds with different refractive indices were also introduced to increase the light penetration depth. It was found that glycerol with a refractive index of 1.474 resulted in the greatest improvement in the curing depth of Si3N4 photosensitive paste. Finally, a proposed slurry composition was developed to successfully print silicon nitride ceramics through UV‐curing molding technology. [ABSTRACT FROM AUTHOR]

The effect of CaCO3 particle size on the viscosity of slurry, phase formation, microstructural evolution, and performances of the water‐soluble CaO‐based ceramic core sintered at different temperatures was systematically investigated and discussed, and the particle gradation orthogonal experiments were used to adjust flexural strength, water‐soluble rate, shrinkage rate, apparent porosity, and hygroscopicity rate. The results showed that the finer particle size increased the effective contact area between CaO and SiO2, which promoted the generation of CaO–SiO2 system phase and the dense microstructure in the sintered CaO‐based cores. The higher sintering resulted in dense microstructure. The optimal gradation scheme included 28 wt.%, 56 wt.%, and 16 wt.% CaCO3 powder with D50 = 11.0 µm, 6.17 µm, and 4.62 µm, respectively, and the resulting flexural strength was 9.57 MPa, water‐soluble rate was 65.37 g/h in 60°C water, shrinkage rate was 8.62%, porosity rate was 38.85%, presenting a well‐balanced comprehensive performance, which is significant for the complex internal castings. [ABSTRACT FROM AUTHOR]

This study investigated the impact of various types of deflocculants with different chemical composition on ceramic slurries rheology. Organic and inorganic plasticizers were substituted for sodium silicate plasticizers in floor tile recipes, and their effects on rheology were assessed. The interactions of these materials with the silicate and ceramic slurry in terms of synergistic, antagonistic, and additive properties were then determined. In addition, the physico-mechanical properties of the ceramic bodies obtained using commercial plasticizers were investigated. Microstructural analysis using scanning electron microscopy (SEM) and mineralogical properties using x-ray diffraction (XRD) were performed. Results revealed that the addition of silicate to the slurry had a synergistic effect on rheology, reducing second viscosity to 50 s with a thixotropy ratio of 22%. Moreover, the flexural strength of the sample with 1% silicate addition increased by 13.6%, indicating positive effects on physico-mechanical properties. SEM analysis indicated the formation of a more uniform dispersion of particles with silicate addition. These findings suggest that incorporating silicate into ceramic slurries can effectively enhance both rheology and physico-mechanical properties, holding significant implications for ceramic tile and product manufacturing. [ABSTRACT FROM AUTHOR]

The geotechnical centrifuge is an efficient alternative to the slurry consolidometer and settling columns for expedited testing of mine tailings and dredged clay slurries, while accurately reproducing the field stress conditions. Existing numerical models for centrifuge consolidation use piecewise linear and finite-difference methods, and are computationally expensive. This study introduces, for the first time, a finite-element formulation for centrifuge finite-strain consolidation. The proposed model accounts for the nonlinearity induced by the hydraulic conductivity, soil compressibility, and acceleration factor variation along the depth of the centrifuge test specimen. The model incorporates the modified Newton–Raphson method and an implicit time integration technique, leading to a significant reduction in the computational expense. The settlement rate curves generated by the proposed model are validated with corresponding experimental data from the literature studies. The computational cost of the proposed model and existing finite-difference based models are compared for centrifuge and normal gravity consolidation testing conditions. Finally, a parametric analysis is presented to show the influence of various parameters on the functional time steps chosen for the finite-element simulations. The model demonstrates computational robustness and is instrumental for parameter estimation through inverse analysis, and prediction of in-field finite-strain consolidation behavior of slurry wastes. [ABSTRACT FROM AUTHOR]

Based on the forming methods of ceramsite foam concrete, this paper studied the influences of the pretreatment method of ceramsite, the incorporation method of ceramsite and the adding method of mixing water on the work performance, dry and wet density, compressive strength, bottom grip performance and ceramite distribution of ceramsite foam concrete, and determined the optimal forming methods of ceramsite foam concrete. The results show that slurry expansion degree can be effectively improved by the saturated water pretreatment method of ceramsite and the method of adding mixing water twice. Different forming methods have little influence on the aggregate expansion degree of ceramsite foam concrete. The dry and wet density of ceramsite foam concrete is affected by the incorporation method of ceramsite and mixing water. The adding method of mixing water twice and wet mixing of ceramsite are beneficial to improve the compressive strength of ceramsite foam concrete. The pretreatment method of ceramsite determines the bottom grip performance, and the adding method of mixing water also affects the bottom grip performance. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are a promising technology to promote the phase-out of fossil fuel vehicles. Increasing efforts are focused on improving their energy density and safety by replacing current materials with more efficient and safer alternatives. In this context, binary composites of organic ionic plastic crystals (OIPCs) and lithium salts show promise due to their impressive mechanical properties and ionic conductivity. Taking advantage of this, the present paper substitutes the commercial non-electrochemically active binder with an OIPC component, N-ethyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide ([C2mpyr][FSI]), in combination with LiFSI. Slurry-formulation experiments revealed that varying the new binder's composition allows the production of diverse LiFePO4 (LFP) cathodes via the conventional fabrication process. Large amounts of OIPC−lithium salt mixtures in the composition yielded thick electrodes with expected nominal areal capacities of up to 3.74 mAh/cm2, where the balanced composition with a reduced Li+ concentration can demonstrate >1.5 mAh/cm2 at 0.1C. Lowering the amount of these ion-conductive binders enabled LFP cathodes to perform effectively under fast cycling conditions at a C-rate as high as 2C. Preliminary battery tests with a limited Li+ source demonstrated the feasibility of full-cell operation without using the lithium-metal anode. This work paves the way for developing advanced rechargeable batteries using OIPC-based ion-conductive binders for a wide range of applications. [ABSTRACT FROM AUTHOR]

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Non-Newtonian fluids are widespread in industry, e.g., biomedical, food, and oil and gas, and their rheology plays a fundamental role in choosing the processing parameters. Centrifugal pumps are widely employed to ensure the displacement of a huge amount of fluids due to their robustness and reliability. Since the pump performance is usually provided by manufacturers only for water, the selection of a proper pump to handle non-Newtonian fluids may prove very tricky. On-field experiences in pump operations with non-Newtonian slurries report severe head and efficiency drops, especially in part-load operations, whose causes are still not fully understood. Several models are found in the literature to predict the performance of centrifugal pumps with this type of fluids, but a lack of reliability and generality emerges. In this work, an extensive experimental campaign is carried out with an on-purpose test bench to investigate the effect of non-Newtonian shear-thinning fluids on the performance of a small commercial centrifugal pump. A dedicated experimental campaign is conducted to study the causes of performance drops. The results allow to establish a relationship between head and efficiency drops with solid content in the mixture. Sudden performance drops and unstable operating points are detected in part-load operations and the most severe drops are detected with the higher kaolin content in the mixture. Performance drop investigation allows to ascribe performance drop to gas-locking phenomena. Finally, a critical analysis is proposed to relate the resulting performance with both fluids' rheology and the gas fraction trapped in the fluid. The results here presented can be useful for future numerical validation and predicting performance models. [ABSTRACT FROM AUTHOR]

The implementation of large-diameter flood diversion pipelines in urban areas serves as an effective strategy to address urban waterlogging issues, which can enhance the resilience of cities to a certain extent against extreme precipitation events. This case study delineates the Zhengzhou Jinshui River flood diversion project, which employs the ultra-large-buried jacking prestressed concrete cylinder pipe (JPCCP), offering a summary and analysis of the pipe design and construction technologies employed in the JPCCP project within collapsible loess stratum, and the study also analyzes the pull-back scheme of the incident involving the front-end sinking of the machine head. Through on-site monitoring experiments, the variation patterns of contact pressure and slurry pressure of large-diameter JPCCPs were analyzed. The results demonstrate that the trends in contact pressure and slurry pressure exhibit a general consistency. During the jacking process, the pressure around the pipe can be categorized into three distinct phases based on grouting frequency or pressure, with notable variations in the pipe–soil–slurry contact state. The difference between the contact pressure and slurry pressure (termed as effective soil pressure) serves as a more accurate method for determining the pipe's operational state. Moreover, the effective earth pressure at the pipe top demonstrates a higher degree of consistency with the calculation results prescribed by the standards ATV A161 and ASCE 27. [ABSTRACT FROM AUTHOR]

Coal gangue is a solid waste produced in the coal mining process. During the mining process, mining-induced overburden fractures are a favorable place for the storage of coal gangue; therefore, coal gangue can be incorporated into filling materials for harmless disposal. Overburden isolated grout filling is a better technology for solid waste reduction, which is currently in development. This paper delves into the methodology of large-scale coal gangue disposal, utilizing this specific technology. With reference to fly ash granules and their slurry characteristics that have been previously applied successfully, raw gangue was pulverized and transformed into a slurry. This experiment then investigated the fundamental characteristics of the gangue powder solids and slurry. This study's findings reveal that the composition types of granule oxides following gangue pulverization closely resemble those of fly ash, with minimal content differences observed between identical oxides. Regarding slurry characteristics, the plastic viscosity of fly ash slurry ranged from 0.45 to 145.2 mPa·s, whereas the plastic viscosity of gangue slurry varied between 2.1 and 56.4 mPa·s. Notably, the stability and fluidity of the gangue slurry surpassed those of the fly ash slurry. Furthermore, regarding the filling efficiency, the compaction coefficient of gangue slurry is less than that of fly ash. Consequently, under identical grouting conditions, a larger mass of solids can be disposed of using gangue slurry compared to fly ash. The research findings facilitate the implementation of a practice involving the overburden isolated grout filling of over million tons of coal gangue in the 21404 working face of the Hulusu coal mine, located in Inner Mongolia, China. This practice has demonstrated a daily filling capacity of up to 4000 t, accumulating to a total gangue filling mass of 1,068,000 t. This study's findings present a viable and efficient approach to the large-scale, environmentally friendly disposal of coal gangue. [ABSTRACT FROM AUTHOR]

Fine debris is an important component of natural debris flows. Previous studies focused primarily on the clay minerals found in the fines, and non-clay minerals were often neglected. The effects of mineralogy of fines on debris-mass slurrying and flow behaviors of the resultant slurries are examined herein. The fines (≤0.04 mm) in the <5 mm fraction of the Dongyuege Creek debris-flow deposit is replaced with five other mineral powders with the same maximum particle size. Four types of separate and sequential experiments related to debris slurrying and slurry behaviors are carried out with the prepared clastic materials. The obtained slurrying index ranging from 0.08 to 0.18 shows that non-clay minerals also can function as the fine fractions of debris-flow materials, so long as the requirement of grain size distribution is met. Equidimensional, non-clay minerals making up fines of debris flows can increase the upper solid concentration limits of slurrying (with a maximum of 0.692) and peak values of relative excess water pressure (measured maximum mean peak value is 0.99), leading to higher momentum and higher competence, and thereby more destructive catastrophe. The sediments with platy non-clay mineral-dominated fines have potential for mobilizing into small- to medium-size debris flows with a relatively small competence. Clay minerals in the fines may indeed enhance the liquefaction potential of debris masses by expanding the difference between upper and lower solid concentration limits of slurrying (0.413 and 0.238, respectively, for pure kaolinite), but they significantly suppress the momentum, competence, and destructive power of potential debris flows by lowering upper solid concentration limit of slurrying of debris masses. Alpine catchments rich in non-clay minerals, notably those releasing dolomite into loose sediments, may be more prone to threatening and destructive debris flows. The basin producing clay minerals should be more susceptible to low-magnitude/high-frequency debris flows with less devastating consequences. [ABSTRACT FROM AUTHOR]

The cathode of a lithium‐ion battery (LIB) is made from a slurry of cathode active materials, conductive additives, and binder mixtures, which is blade‐coated to fabricate the cathode electrode. The blade coating is a wet coating technology, which requires a heat treatment process after casting to volatilize the solvent. In addition, due to the dense surface, the reaction occurs mainly on the surface during the charge and discharge cycle, which accelerates degradation. To address these problems, this study introduces electrospun coatings during slurry casting. Electrospinning (ES) is a fast, easy, and low‐cost process that is not limited by external conditions and is typically used to produce nanofibers. However, if the polymer solution concentration is extremely low, a porous film can be formed by electrospraying. Porous films tend to degrade more slowly because the reaction occurs across the entire electrode. In addition, ES does not require a drying process as the solvent is volatilized during the process. While the blade coating shows 47.13% retention after 100 cycles at 1C, ES shows an improved retention of 75.98%. The application of ES to LIB results in a significant improvement in cycle performance, which can be developed into a breakthrough technology in electrode fabrication. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)