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Silicon carbide (SiC) is a multifunctional material with a myriad of potential applications, from high-power electronics to friction applications to power generation. Grafting preceramic polymers (PCPs) from SiC nanoparticles would create a platform for forming SiC via a polymer derived route that would have advantages over simple particle-PCP slurries and may enable new additive manufacturing inks or spreadable coatings with controlled rheology. Grafting PCPs directly on SiC powders would greatly improve dispersion of these particles and yield a single component system. Moreover, PCP-grafted-SiC would be a new addition to the burgeoning field of polymer grafted nanoparticles (PGNPs). Herein, SiC nanoparticles were surface-modified in a grafting-from polymerization reaction to create polycarbosilane (PCS) grafted SiC. Surface grafting was verified through a number of analytical techniques and the synthesized materials were pyrolyzed at 1600 °C. The PCS-grafted SiC retained 66 % of its pre-pyrolysis mass, representing a significant improvement over PCS-grafted silica nanoparticles from our previous work (20 wt% yield). In addition to an increased ceramic yield, the grafting of PCS to SiC also resulted in the formation of a SiC phase not present in the simple physical mixture of SiC nanopowder in PCS. This study demonstrated that PCP-grafted nanoparticles (GNPs) can be synthesized utilizing non-oxide nanoparticle cores with desirable rheology, opening possibilities for future ceramic inks and coatings. [ABSTRACT FROM AUTHOR]

Al 2 O 3 reticulated porous ceramics (ARPCs) are extensively employed in high-temperature catalytic support, molten metal filtration, and porous media combustion because of their high specific surface area and heat resistance. The high specific surface area is usually maintained by high apparent porosity, but unfortunately, the accompanying poor mechanical properties severely compromise the durability of ARPCs. To synergistically improve the mechanical properties and apparent porosity, a new strategy was proposed to prepare ARPCs with textured structures of in situ interlocking Al 2 O 3 platelet integration using vacuum impregnation Na 3 AlF 6 –SiC–Al 2 O 3 slurry technique. The obtained textural structure had a significant strengthening effect on ARPCs, attributed to the increased contact area among non-equiaxed grains, and the compact growth of Al 2 O 3 platelets with high aspect ratios provided the high apparent porosity and specific surface area of ARPCs, resulting in compressive strength as high as 3.93 MPa at an apparent porosity of 85.31 %, as well as the degradation of Congo red up to 75.35 % due to the Al 2 O 3 platelets facilitating the loading of TiO 2. [ABSTRACT FROM AUTHOR]

The inherent brittleness of ceramics poses significant challenges in the fabrication of hollow ceramic fibers, severely constraining their practical applications. In this study, a novel method for creating three-dimensional hollow fiber ceramic structures using UV-assisted single-channel direct ink writing was demonstrated. A concentric single-channel nozzle featuring shell/core structure was devised through the coaxial embedding method, and this specially designed nozzle was manufactured using digital light processing technology. During the UV-assisted direct ink writing process, the photosensitive ceramic slurry can be rapidly cured in place under the irradiation of UV light, ensuring high fidelity of the printed components. The hollow fiber structure produced in this study has a circular, pentagram, triangular and quadrilateral inner core, which can be adjusted according to the designed nozzle structure. This approach facilitates a straightforward and expedited creation of scaffolds featuring small-diameter hollow fiber structures, broadening the scope of potential applications for direct ink writing. [Display omitted] [ABSTRACT FROM AUTHOR]

We report the first work on the development of biodegradable acoustic foams from self‐grown bacterial cellulose (BC) from kombucha solution and green processing techniques. Kombucha BC‐agar and kombucha BC‐polyvinyl alcohol foams were fabricated by using slurries of BC pellicles mixed with the additives, froze for 24 h, and recast into foams using the freeze‐drying method. The foams were aerogel‐like with a density 20 kg/m3, thermally stable upto 220 °C, and crystallinity ~74%. Morphological analysis revealed macropores with coarse walls in agar‐based foams, whereas the PVA‐based foams comprised a polydisperse pore network with coarse walls. A broadband absorption was observed with a maximum of 0.4 for the 2.5‐mm‐thick single‐layer foams and 0.9 for the 12‐mm‐thick multilayer foams. The sound absorption was found to be on par with the biodegradable foams of agar and other cellulose‐rich materials such as agricultural residue, yet with a lightweight. Being largely porous, the foams had little transmission loss. As the densities and the crystallinities of these foams are tunable by the addition of other polymers, the results from this study provide scope to explore BC‐based lightweight materials for large‐scale fabrication suitable for sound absorption over specific regimes. [ABSTRACT FROM AUTHOR]

Real-time Fe content monitoring in iron ore slurry is crucial for evaluating concentrate quality and enhancing mineral processing efficiency. Laser-induced breakdown spectroscopy (LIBS) is a promising technique for the online monitoring of elemental content at industrial sites. However, LIBS measurements are hampered by the matrix effect and the self-absorption effect, limiting the precision of linear analytical processes. To overcome this, we propose to introduce a nonlinear processing unit based on the S-transform to incorporate nonlinearity into the data analysis process. This approach integrates a feature selection unit based on the spectral distance variable selection method (SDVS), a nonlinear processing unit based on the S-transform (ST), and a partial least squares regression model (PLS). To demonstrate the improvement in accuracy achieved through nonlinear processing, a comparative analysis involving five models, Raw-PLS, SDVS-PLS, ST-PLS, SDVS-ANN, and SDVS-ST-PLS, is conducted. The results reveal a significant improvement in the performance of the SDVS-ST-PLS model, effectively facilitating the successful application of the LIBSlurry analyzer to the mineral flotation process. [ABSTRACT FROM AUTHOR]

In this study, Si powder was used as raw material, Si 3 N 4 powder as a diluent, Al 2 O 3 , MgO, Y 2 O 3, and La 2 O 3 as sintering additives to prepare Si 3 N 4 ceramic with excellent properties using gelcasting and reaction re-sintering method. When the solid content of the slurry is 57.3 %, the viscosity is less than 1 Pa · s during the gelcasting process. After the reaction re-sintering, the sintered body of Si 3 N 4 exhibited a bulk density of 3.15 ± 0.05 g/cm3, a relative density of 96 ± 1 %, open porosity of 5.7 %, bending strength of 610 ± 20 MPa, elastic modulus of 235 ± 10 GPa, thermal conductivity of 48 ± 5 W/(m·K), and a linear shrinkage rate of 12–13 %. These parameters indicate that Si 3 N 4 ceramic possesses outstanding mechanical properties and thermal conductivity. [ABSTRACT FROM AUTHOR]

Hydration of MgO is a potential technology for economically preparing Mg(OH)2 slurry. Understanding the rheological behavior evolution of the slurry during MgO hydration, particularly in the presence of hydration agent, is essential for better control of the hydrated Mg(OH)2 slurry's rheology. In this work, Mg(OH)2 slurry was prepared by hydrating MgO in the presence of glycine. The effect of glycine on the rheological behavior of the hydrated Mg(OH)2 slurry have been investigated by means of viscosity, shear stress, sedimentation measurements, particle size distribution, 1H nuclear magnetic resonance relaxometry and zeta potential. Results showed that shear thinning rheological slurry could be made by hydration at 80 °C for 1 h. The yield stress of the slurry is 27.49 ± 0.81 Pa, and no settling occurs within 7 days. Yet, in the absence of glycine, the structure of the slurry was unstable and easily settled even after 8 h of hydration. Glycine has multiple effects on the slurry's solid loading, particle morphology, particle size distribution, and zeta potential of the slurry. In addition, the neutral zwitterionic form of glycine may serve as an inter-particle lubricant, reducing viscosity. [ABSTRACT FROM AUTHOR]

Mineral slurry preparation and pipeline transport require careful particle size distribution and additive selection to ensure cost-effective and reliable transportation. The research described here was aimed to better understand the flow behavior of a limestone sample by combining coarse and fine particles and a low-cost natural additive, Saponin, derived from Sapindus laurifolia. Four distinct bi-modal suspension samples were formed using various mixtures of limestone samples with sizes varying from 0–53 and 75–106 µm. The rheological characteristics of the suspension were investigated at shear rates of 50 to 500 s−1 for solid concentrations 40–70% by weight. The additive's critical micelle concentration was found to be 1.8 weight percent. The Hershel-Bulkley model fits the experimental data the best. The appropriate proportion of coarse particles was discovered to be 30% based on critical factors such as apparent viscosity and pressure drop. The addition of the surfactant reduced the surface tension, increased the wettability, and decreased the particle-particle interaction to stabilize the limestone-water suspension. [ABSTRACT FROM AUTHOR]

Collapsibility significantly impacts the bearing capacity of pile foundations in loess areas. To improve the load-bearing capacity of piles, the pile-base postgrouting technique is widely used worldwide. However, there are still several related issues to be solved: the impact of loess collapsibility on the bearing capacity; the effectiveness of the pile-base postgrouting technique in enhancing the bearing capacity; and the diffusion pattern of the grout during the grouting process. To investigate these issues, this experiment utilizes a visual static pressure device combined with numerical simulation. According to the experiment, the maximum axial force and neutral point appeared to shift downward after grouting, resulting in a 17.5% increase in the bearing capacity of the pile foundation. Additionally, an increase in grouting pressure leads to a rise in both the number of shear cracks and the diffusion radius. As the permeability of the grout improves, the number of shear cracks and diffusion radii tend to stabilize after an initial increase. These discoveries enable a thorough analysis of the changes in side friction and base resistance of postgrouted piles in collapsible loess. Furthermore, they provide valuable references and guidance for the implementation of the pile-base postgrouting technique in loess areas. [ABSTRACT FROM AUTHOR]

In recent years, the recycling and reutilization of shield tunneling residues (STR) have received extensive attention in underground engineering. To optimize the method of resource utilization of STR, this paper introduces a replacement method of STR slurry. The STR are incorporated into concrete and prepared as STR concrete (STRC) using a coarse and fine aggregate shell production process. By optimizing the mixing method of STR slurry, we obtained the best mixing process, and studied the influence of STR dosage and water–binder ratio (w/b) on the compressive strength of STRC. The results revealed that the air-dried STR preliminarily crushed to about 15 mm can be used to prepare STRC by extending the mixing time of STR slurry. The compressive strength of the concrete significantly depends on the dosage of STR slurry. The strength decreases significantly with the increase of STR dosage, and the recommended dosage is about 10%. The influence of the w/b on compressive strength is similar to that of ordinary concrete. A predictive model for the compressive strength of STRC was established by analyzing the relationship between the dosage of STR, w/b , age, and the strength of STRC. [ABSTRACT FROM AUTHOR]

Y 2 O 3 and CaO are ideal ceramic materials for precision casting of TiAl alloy, overcoming challenges associated with intricate component removal, such as turbine blades, leveraging the stability of Y 2 O 3 and the water solubility of CaO. To address these challenges, we employed Isobam104 in a novel gel casting method, serving as both a dispersant and a gelling agent. This method enabled us to create a stable Y 2 O 3 –CaCO 3 slurry with high solid content (up to 55 vol%) and low viscosity (101.51 mPa·s at a shear rate of 10 s−1). Following sintering at 1500 °C for 2 h, Y 2 O 3 –CaO composite ceramics were produced. Surprisingly, two distinct characteristics of CaO were noted. One showed a rod-shaped morphology with high chemical reactivity crucial for water solubility, while the other displayed a flat-like feature, forming a well-maintained interface due to its coherent or semi-coherent matching relationship with Y 2 O 3 , thereby providing excellent hydration resistance. Ultimately, we acquired composite ceramics showcasing a 30-day "shelf life" alongside exceptional water solubility. This establishes the theoretical groundwork for storing and employing soluble ceramic cores in the precision casting of TiAl alloy. [ABSTRACT FROM AUTHOR]

Flocculation sedimentation state observation could be used to facilitate interaction visualization in laboratories and establish theories for industrial manufacture. Herein, kaolinite was obtained from different sources and labeled as K1 and K2. Those characteristic characterizations indicated that silica sand was difficult to remove from refined commercial kaolinite with different sources. Some biosafe and removable surfactants have been used to evaluate the flocculation sedimentation state of kaolinite-surfactant slurry for a long time, indicating those surfactants could accelerate the settling velocities within a certain range, which could be attributed to sufficient surfactant-kaolinite interactions, but decelerate the settling velocities with the excess surfactant addition, which could be attributed to the surfactant-water colloidal characteristic. Then, the flocculation sedimentation mechanism was illustrated in detail based on the kaolinite-surfactants interaction, indicating that the excellent flocculation sedimentation state was beneficial to silica removal with sedimentation method, but the difficult flocculation sedimentation state was beneficial to size classification with differential centrifugation. [ABSTRACT FROM AUTHOR]

Soil conditioning is essential for addressing the stratum applicability problem of earth pressure balance (EPB) shields. Under high water pressures, EPB shields spew water and soil when excavating coarse-grained strata. Typically, foam combined with polymers and slurry is used to solve spewing. However, in current techniques, slurry, foam, and the other agents are mixed with soil separately, their synergistic effect is seldom realized. In this study, an anionic surfactant was used to foam in bentonite slurry to form bubble–slurry to maximize the synergy between bubbles and slurry. The slump, volume stability, and permeability test of bubble–slurry-conditioned sand was conducted to examine the conditioning effect, and the stratum applicability of bubble–slurry was determined from the perspective of permeability. It was found that the conditioning effect of bubble–slurry in coarse gravel soil was excellent and could expand the applicability of EPB shields. The main stabilization mechanism of bubble–slurry is that bentonite particles provide a space barrier for bubbles. And three seepage modes of bubble–slurry-conditioned sand were innovatively defined, and the occurrence conditions of the three seepage modes were analyzed according to the permeability coefficient of sand, initial dynamic shear force of bubble–slurry, and hydraulic gradient. [ABSTRACT FROM AUTHOR]

In this study, a γ‐boehmite (γ‐AlOOH) – PEG/polyethylene (PE) lithium‐ion battery separator was fabricated using a dip‐coating method, with γ‐AlOOH nanowhiskers being synthesized directly through a hydrothermal process,and polyethylene glycol 10000 (PEG‐10000) was chosen for the first time as a dispersant for the γ‐AlOOH nanowhiskers in the PE coating slurry{Lee, 2014 #7}. Simultaneously, the membrane's performance was characterized, confirming the significant dispersion effect of PEG‐10000, resulting in a porosity as high as 64 % in the AlOOH‐PEG/PE, a substantial increase compared to the PE separator (40 %). The AlOOH‐PEG/PE separator maintains its structural integrity even after a 0.5 h test at 200 °C, showcasing outstanding stability and significantly improved safety. Besides, the LIB half cells assembled with the PE/AlOOH‐PEG separator exhibited remarkable performance, with a capacity of 73.9 % in power capability (at 5 C rate) and a 97.1 % discharge capacity retention rates in cycle performance (after 400 cycles, at 2 C rate). Furthermore, lithium iron phosphate (LiFePO4) batteries utilizing the AlOOH‐PEG/PE separator demonstrated significantly enhanced cycling stability and rate capacity. [ABSTRACT FROM AUTHOR]

This study examines and compares the impact of various interfacial modification strategies in optimizing the contact resistance between the rigid ceramic electrolyte and cathode active material (AM) in solid‐state sodium‐ion batteries (SSBs). All the cells are fabricated using Na3.1V2P2.9Si0.1O12, Na3.456Mg0.128Zr1.872Si2.2P0.8O12, and Na as a cathode AM, solid electrolyte (SE) and anode, respectively. The AM/SE interface is modified by (1) wetting the interface with organic liquid electrolyte (LE), (2) slurry casting and sintering a thin layer of composite cathode, and (3) infiltrating AM precursors inside the porous SE structure followed by drying and sintering. Despite exhibiting a stable cyclability performance, the SSBs prepared using the LE modification and composite cathode approach possess a low AM loading of < 1 mg·cm−2. On the other hand, the SSBs with infiltrated‐cathode exhibit a superior discharge capacity of ∼ 102 mAh·g−1 at 0.2C and less than 5% capacity fading after 50 cycles at room temperature. Notably, these cells contain a high AM loading of 2.12 mg·cm−2. The microstructural analysis reveals the presence of AM particles inside the pores of the porous SE, allowing for the efficient insertion/removal of sodium ions. The porous scaffold of SE not only provides continuous sodium‐ion conduction pathways inside the cathode structure but also renders stability by accommodating stress induced by volume change during repeated cycling. The outcomes of this work demonstrate the effectiveness of the wet‐chemical infiltration technique in improving the AM loading and storage capacity performance of SSBs working at 25°C. [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 shear-thickening polishing (STP) method, a flexible polishing technique developed in recent years, was utilized to obtain high surface quality of yttrium aluminum garnet (YAG) crystal effectively. The effect of polishing slurry pH value, which characterizes the chemical action between slurry and YAG crystal, on the material removal rate and surface roughness of YAG crystal was investigated, and the mechanism of the chemical action between YAG and slurry in STP process was revealed through X-ray photoelectron spectroscopy (XPS) analysis. The influence of polishing speed and abrasive concentration, which were relating with mechanical action, on the polishing effects was also studied. The experimental results show that when the pH value of the polishing slurry is lower than 11, the dissociation of chemical bonds and the formation of new bonds on the surface of the YAG crystal are predominantly found, resulting in a lower material removal rate. While the pH value of polishing slurry reaches 13, a reaction layer consisting of Al 2 SiO 5 and Y 2 SiO 5 , which has lower hardness than abrasive, is formed on the surface, and this reaction layer can be removed by mechanical action efficiently. The surface roughness S a decreases from 60 ± 10 nm to 0.38 ± 0.06 nm in 15 min with MRR reaches 117.30 nm/min, which is 4.3 times higher than that of chemical mechanical polishing. Based on the results of XPS analysis, the material removal mechanism of YAG polished by STP is proposed. As revealed by the results, STP with chemical action provide a high efficiency polishing method for the high surface quality YAG crystal. [ABSTRACT FROM AUTHOR]

Zirconia-toughened alumina (ZTA) ceramics have attracted much attention in the medical field as joint replacement materials due to their good mechanical properties and biocompatibility. However, the flexural strength of conventional ZTA is still slightly insufficient in traditional preparation techniques. In this study, by improving the slurry system, the effects of the solid content of the slurry, additives, and the pH of the slurry on the slurry system were investigated. ZTA powders with a uniform particle size distribution, high degree of sphericity and high flowability were prepared by spray granulation. The mechanical properties, microstructure and biocompatibility of the ZTA pressing were investigated after degreasing and sintering processes. The results showed that the hardness of the prepared ZTA ceramics was 1658.24 ± 28.04 H V, the fracture toughness was 4.016 ± 0.027 MPa m1/2, and the biaxial bending strength was 501.43 ± 21.44 MPa, and the three-point bending strength reached 635 MPa. The ZTA ceramics also possessed good biocompatibility and a low haemolysis rate, which aligns with the requirements of clinical biomedical implant materials. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of the morphology, mechanical properties, erosion resistance, and machine learning modeling of Si 3 N 4 +TiC + VC and CrNi based ceramic coatings deposited via plasma spraying. The cross-sectional morphology analysis revealed good mechanical interlocking between the coatings and the substrate, with pores predominantly observed in the Si 3 N 4 +TiC + VC coating. The coating thicknesses were measured as follows: 260 μm for Si 3 N 4 +TiC + VC, 243 μm for Si 3 N 4 +TiC + VC blended with CrNi, and 232 μm for pure CrNi coating. Mechanical characterization showed that microhardness values ranged from 1933 HV for Si 3 N 4 +TiC + VC coating to 499 HV for pure CrNi coatings. Slurry erosion tests demonstrated that pure Si 3 N 4 +TiC + VC coating exhibited superior erosion resistance at 90° impingement angle compared to other coatings. Additionally, a rigorous evaluation of over 20 machine learning regression models revealed that Gaussian Process Regressors and Artificial Neural Network (ANN) with a layer size of 20, displayed satisfactory performance in modeling mass loss prediction. The erosion mechanisms observed in the coatings provided valuable insights into their response to slurry erosion, highlighting the influence of coating composition and impingement angles. The findings underscore the potential of Si 3 N 4 +TiC + VC ceramic coatings to enhance the erosion resistance of stainless steel, offering promising applications in various industries. [Display omitted] [ABSTRACT FROM AUTHOR]

The study employed the water-based casting technique to prepare BST sheets, which were then combined with PDMS to BST composite sheets for wind energy harvesting. By adding 0.3–1.2 mol% Y 2 O 3 as an additive, the dielectric constant and the flexoelectric coefficient of the BST sheets were significantly enhanced. The Y 2 O 3 and BST powders were mixed to form a casting slurry with the appropriate viscosity, which was then cast into a sheet. After the sintering process, silver electrodes were coated on both surfaces of the sheet. To enhance the flexibility of the sheet, PDMS was applied to the silver-coated surfaces, creating a "sandwich structure" composite sheet. The flexoelectric properties of the composite sheets are characterized utilized the micro cantilever beam method. The energy harvesting experiments, conducted in a simulated wind tunnel environment, demonstrate that the composite sheets exhibit varying flexoelectric properties and energy conversion efficiencies, depending on their thickness. When the doping amount of Y 2 O 3 is 0.6mol%, the composite sheets with a BST layer thickness of 200 μm exhibit the highest flexoelectric coefficient of 1.1 μC/m; the composite sheets with a BST layer thickness of 100 μm exhibit the strongest current output capability of 4.2 nA. These findings indicate that the developed composite sheets could be promising for applications in renewable energy harvesting, particularly for capturing and converting wind energy into useable electrical power. [ABSTRACT FROM AUTHOR]

This study proposes porous block structures as a viable alternative to conventional pebble bed structures, aiming to overcome the structural drawbacks including low packing fractions, extensive stress concentrations, and low thermal conductivity. To validate the feasibility of the porous block structures, Gyroid Li 2 TiO 3 block breeders were prepared by the hybrid process of stereolithography and gelcasting. The resulting Gyroid Li 2 TiO 3 block breeders, measuring ∼18.8 × 18.8 × 18.8 mm3, achieved a high packing fraction of ∼78.8% through optimized slurry and sintering at 1100 °C for 3 h. These Gyroid Li 2 TiO 3 block breeders exhibited clear contours, integrated channels, a compressive strength of 8.78 MPa, and a low isotropic sintering shrinkage of ∼6%. The hybrid process demonstrated enormous advantages over the reported 3D printing for the preparation of porous block breeders with low shrinkage and large-sized dimensions. This study offers an effective avenue for the manufacture of porous block breeders with tunable tritium-releasing channels and large-sized configurations. [ABSTRACT FROM AUTHOR]

The limitations of oxide/oxide ceramic matrix composites lie in the need to improve their mechanical properties. It is challenging to reconcile the conflict between matrix densification at high temperature and the potential thermal damage to fibers. The concept of using element doping to control the sintering behavior of matrix was initially applied to prepare alumina-based ceramic matrix composites (CMCs). To lower the sintering temperature of the Al 2 O 3 matrix, MnO 2 dopant was used as a sintering aid. As a result, the thermal damage to alumina fibers was decreased, and the mechanical properties of the composite were significantly enhanced. The effect of MnO 2 content on the bending strength and micro-morphology of the composite was investigated. The composite exhibits optimal mechanical properties with a 0.01 wt% MnO 2 doping, and its bending strength is approximately 405 MPa. The investigation aimed to determine the mechanism by which the fluctuation in micro-mechanical properties of the composites with different MnO 2 contents. After the thermal aging at 1000℃ for 500 h, the bending strength of the N610/Al 2 O 3 -0.01 composite decreases to 297 MPa. The evolution and mechanism of thermal aging damage have been studied. [ABSTRACT FROM AUTHOR]

In this article, physical model test and numerical simulation are used to study the formation of filter cake and the filtration performance of the geotextile on the lateral boundary of the ultra-fine tailings grouting geotextile tubes from macro and micro levels. At the macro level, the effects of different grouting flow rates and tailings slurry mass concentrations on the surface filter cake formation and the dehydration performance of geotextile on the lateral boundary of the geotextile tubes were analyzed. At the micro level, the use of CFD-DEM method for fluid and particle of two-way coupling numerical simulation research, lateral drainage boundary of superfine tailings in tubes filter cake forming process is analyzed. The research shows that the increase of grouting flow rates and tailings slurry mass concentrations will make the thickness of filter cake great and the structure more compact, which will lead to more serious silting of the surface layer of geotextile and greatly reduce the dehydration performance; The numerical simulation results regularity is consistent with the results regularity of physical model test on the formation of filter cake on geotextile surface of geotextile tubes: the larger the slurry inlet speed and particles concentrations, the more complete the formation of filter cake on geotextile surface, the denser the cake structure, and the less tailings loss. By studying the effects of grouting flow rates and slurry mass concentrations on the surface filter cake formation and tubes dehydration, this article aims to find suitable slurry filling construction conditions and explore the main influencing factors caused by dehydration and consolidation of ultra-fine tailings grouting geotextile tubes, so as to provide some help for the subsequent flocculating of ultra-fine tailings to solve the problem of surface drying and internal wetting of geotextile tubes. [ABSTRACT FROM AUTHOR]

Introduction: Cattle slurry used as fertilizer in crop production is a mix of feces, urine, water, and bedding material from the housing system. Previous studies have shown that slurry nitrogen (N) availability to crops is dependent onC/Nratio. As the bedding material can contribute a significant part of total slurry carbon (C), its characteristics may affect the C/N ratio of the slurry. There is increasing interest in using the solid fraction from mechanical slurry separation as bedding material, and therefore this study investigated the potential effect of this fraction on slurry N availability, compared with more commonly used bedding materials such as straw and sawdust. Methods: In two parallel 28-day laboratory incubations, net mineral N release and Cmineralization fromslurries applied to sandy loam soil weremeasured. The slurries comprised a liquid fraction (LF) from mechanical cattle slurry separation with a screw-press and different added bedding materials. Liquid fraction was mixed with two types of bedding material, solid slurry fraction (SF) and chopped straw, in different proportions, resulting in C/N ratios of 10, 12, and 14 in the slurry. In additional treatments, two other bedding materials, ground straw and sawdust, with slurry C/N ratio 12, were used. Results: For SF and chopped straw, similar negative linear correlations were seen between slurry C/N ratio and net mineral N release after 28 days. Carbon mineralization, expressed as a percentage of total C added, was higher from the mixture containing SF than that containing straw, while no clear relationship with C/N ratio was found. At slurry C/N ratio 12, net release of mineral N was 28-39% of total N and decreased in the order: sawdust>chopped straw=SF=ground straw. Net C mineralization at the same slurry C/N ratio was 33-46% and decreased in the order: SF=ground straw>chopped straw>sawdust. Discussion: For bedding materials with similar fiber composition (i.e., SF and straw), differences in C availability due to particle size or degree of degradation by microorganisms did not influence slurry N availability measurably. For sawdust, with high lignin content, the results indicate that limited C availability may lead to lower slurry N immobilization. [ABSTRACT FROM AUTHOR]

Silicon (Si) and silicon/graphite (Si/Gr) composite anodes are promising candidates due to their high theoretical capacity, low operating potential and natural abundance for high energy density Li‐ion batteries. Green electrode production, eliminating organic volatile solvents require advancement of aqueous electrodes. Engineering the binder plays a critical role for improving waterborne electrodes. Lithium substituted polyacrylic acid LiPAA has been demonstrated as a promising binder for Si/Gr anodes and for Ni‐rich cathodes in different cell configurations. LiPAA is utilized to minimize the volume expansion during cycling for Si/Gr anodes. LiPAA is formed in situ during cathode slurry preparation to regulate the pH and dimmish the Li loss. Using advanced characterization techniques, we investigated the slurries, electrodes, and active material reaction with LiPAA and its effect to the cycling performance. Our results indicate that the performance of high Si containing anode is limited by the amount of Si in the electrode. The failure mechanism with respect to high Si content was studied thoroughly. Aqueous processed cathodes with LiPAA binder in combination with Si anodes outperformed NMP based cathodes. Hence, LiPAA was successfully utilized as an active binder for both a high Si containing anode and for a Ni rich cathode. [ABSTRACT FROM AUTHOR]

Bentonite slurry is readily available, and extensively used in underground construction, where the in-situ infiltration behavior of the slurry is of great interest. As a solid–liquid biphasic fluid, slurry exhibits distinct fluid properties that set it apart from pure water. These unique properties play a significant role in determining its infiltration behavior during construction, making it a critical factor that cannot be overlooked. In this study, slurry shear tests were carried out using a rotational viscometer to characterize its fluid properties, and constant water head infiltration tests were conducted by a self-designed infiltration device to investigate the infiltration behavior of slurry in sand stratum. In addition, theoretical derivation based on the pipe flow was implemented to simulate the slurry flow in the stratum. The results show that, as the slurry infiltration continues, the relationship between the yield stress and initial hydraulic gradient experienced a "nonlinear to linear" process. The nonlinearity at the early stage of slurry infiltration is related to the evolution of the core phase of the slurry, which is the root cause of the nonlinear evolution of the fluid property and infiltration curves. A predicted relation between the fluid parameters of the slurry and its multiphase infiltration behavior was established, which are able to give a better understanding of the slurry behavior in engineering design. [ABSTRACT FROM AUTHOR]

Aims: Management can largely influence the sustainability and functionality of forest plantations. However, the role of biogas-slurry and biochar application in supporting soil's multifunctionality during afforestation remains poorly understood. Methods: We conducted a six-year field experiment to examine the responses of soil ecosystem multifunctionality (EMF) to the application of biogas-slurry applied annually as four treatments, and a single initial application of four treatments of biochar in a new poplar plantation based on a reclaimed coastal area. The EMF was calculated as the standardized average of multiple soil surrogates of soil functions linked with C, N, and P cycles. Results: Both biogas-slurry and biochar had significantly positive effects on EMF and individual functions, with biogas-slurry having the strongest positive effect, thus promoting carbon stocks and nutrient availability. Furthermore, interactions between biochar and biogas-slurry produced a substantial synergistic effect on soil multifunctionality. The application of biogas-slurry significantly and directly increased the C, N, and P cycle multifunctionality (CCMF, NCMF, and PCMF, respectively). In contrast, a single application of biochar profoundly increased the CCMF but decreased the NCMF, thus requiring a trade-off of multiple elements of soil multifunctionality. Conclusions: We show that organic management has the potential to boost multiple ecosystem functions during afforestation. These findings further highlight the importance of rational fertilization strategies for long-term forest management. [ABSTRACT FROM AUTHOR]

Background: Anthropogenic ammonia emissions, primarily derived from agriculture, lead to air pollution, soil acidification, and surface water eutrophication, all of which adversely affect human health and ecosystems. Slurry treatment technologies in the form of additives represent an underutilized means of reducing gaseous emissions. Information regarding the potential of additives to reduce ammonia in soil surface‐applied slurries is scarce. Aim: This study aims to develop a 15N mass balance technique to quantitatively measure ammonia losses from different slurries containing multiple additives that are applied to outdoor soil‐filled containers. Methods: The experiments were performed under free‐air conditions. Isotopically labeled slurries from biogas, cattle, and pigs containing 18 additives were surface‐applied to soil‐filled containers and exposed for 72 or 48 h. The additives included inorganic and organic adsorbents, five amounts of sulfuric acids, molasses ± effective microorganisms, and water dilution. After termination of the ammonia loss period, a suite of soil preparation steps for the quantitative recovery of the labeled ammonium remaining in the soil was developed, and subsequently the loss of NH4‐N was determined. Results: In the control treatments, ammonia losses from biogas, cattle slurries, and pig slurries averaged 54.4%, 33.9%, and 11.0%, respectively. The adsorbents did not decrease or only slightly decreased ammonia emissions. Ammonia abatement by sulfuric acid was nearly complete at pH values of 5.9 and 5.8 for the biogas and pig slurry, respectively, and about 80% at pH 5.2 for the cattle slurry. In comparison, more moderately decreased pH values with sulfuric acid showed a similar reduction as molasses and a 1:1 dilution for the three slurries. Adding microorganisms to the molasses did not further decrease ammonia losses. Conclusion: The newly developed 15N mass balance technique, which allows a precise estimate of ammonia losses, can serve as a reference method to assess ammonia losses from field‐applied slurries containing various additives and as a standard comparison technique for other ammonia measurement techniques. [ABSTRACT FROM AUTHOR]

Some of the foremost parameters effecting the slurry rheology, preferably the slurry concentration, particle size distribution, and modal distributions, were studied in the current findings, figuring out the variation in shear stress and apparent viscosity using a rotational rheometer. The particle size considered for the test ranges from fine particle size of −75 µm to coarse particle size of +75–300 µm, separated at varied size fractions of +75–105, +105–150, +150–210, and +210–300 µm. The −75 µm bauxite slurry at 60 wt% has shown a maximum static settled concentration (Cw-max) under gravity after 48 h free settlement. This fine particle slurry at varying concentrations of Cw = 45–65% is discerned to behave like a Non-Newtonian Bingham plastic fluid at lower concentrations, unlike the other coarse fraction bauxite slurries at Cw = 55%, which exhibit shear thickening behavior. The present work carried out adds knowledge on the rheological behavior of bimodal, trimodal, and multimodal with four and five different size fraction bauxite slurries in finding the optimum mass concentration for a particle size fraction of (coarse):(fine), obtained in the ratio (25):(75), (25:25):(50), (25:25:10):(40), and (15:15:15:15):(40), respectively of the total 60 wt%. Certain parameters, like yield stress, consistency index (k), and flow behavior index (n), were estimated upon fitting the modal distributions to the Herschel Bulkley model to choose the best particle size distribution of the bauxite sample showing improved slurry stability, rheology, and flow characteristics. [ABSTRACT FROM AUTHOR]

Due to the increasing demand for lead metal, the recovery of fine-grained galena resources is also constantly strengthening. High intensity conditioning (HIC) has been promoted as an efficient technology for enhancing the flotation of fine minerals. In this study, the effect of the HIC process with a multi-bladed impeller on the flotation of fine-grained galena was investigated at different agitation times and speeds. By analysis of flow field characteristics, adsorption experiments, and particle aggregation observation, the correlation mechanism of HIC affecting the flotation of fine-grained galena was revealed. Compared to the results without the HIC, the flotation recovery was 95.38% when the agitation speed was 2000 rpm and the agitation time was 5 min. Mechanistic studies showed that obtaining an appropriate slurry flow rate with external energy input not only benefited the dispersion of galena particles and reagents, but also enhanced their adsorption. The appropriate impeller shear stress can increase the flow rate difference of the slurry, making it easier for fine-grained galena to form clusters with appropriate particle size, compact structure, and small porosity, which promoted mineral flotation. This study will provide a basis for adjusting the floatability of fine sulfide mineral flotation from mixing operations. [ABSTRACT FROM AUTHOR]

Biogas slurry is increasingly adopted as a substitute for chemical fertilizer to improve soil fertility and control soil degradation. But little is known about its long-term effects on different soil layers. This study aims to test if biogas slurry substitution alters soil nutrients and aggregates differently in different layers and how the effects are influenced by straw return. A five-year field trial of a winter wheat–summer maize rotation was established to evaluate the effects of biogas slurry substitution [treatments: control without fertilizer (CK); chemical fertilizer (CF); 50% biogas slurry substitution (BSCF); 100% biogas slurry substitution (BS)] on two soil layers (0–20 and 20–40 cm) under equal N, P, and K fertilization in a Fluvisol. The result showed that compared with CK, fertilization was necessary to maintain soil available nitrogen (AN) and available potassium (AK) in the 0–20 cm layer. Also, fertilization had positive effects on soil EC, TN, and AP, especially in the topsoil. In terms of increasing the degree of water-stable macroaggregation, improving aggregate stability and reducing their crushing rates, CF was superior to biogas slurry substitution because of the greater accumulations of soil N, the most important physicochemical factor regulating soil macroaggregation and stability. The effects of biogas slurry substitution changed with soil layers. In surface soil, BD, water-stable macroaggregates, and aggregate stability significantly increased due to the positive regulatory effects of straw, AP, and EC; whereas in subsoil, they decreased. Inorganic fertilization with straw return functions well in soil structural degradation control and N fertility improvement, especially in the topsoil. Whereas in fields without straw return, biogas slurry substitution may be a feasible and economical choice to improve topsoil structure and also an excellent supplement to provide P and K. [ABSTRACT FROM AUTHOR]

The tunnel face stability is closely related to the migration behavior and clogging mechanism of the slurry particles in granular soils, which is not yet fully understood. In this study, the coupled computational fluid dynamics–discrete element method (CFD–DEM) is adopted to investigate the infiltration behavior of slurry at the particle scale. The full Johnson–Kendall–Roberts (JKR) contact model describing interparticle behavior that accounts for cohesion present even when particles are microseparated after collisions is adopted for clay‐clay or clay‐sand particles and the Hertz–Mindlin model is used for sand‐sand particles. Through simulations, the mechanism of the slurry particle's blockage is identified as physical, frictional and cohesive modes, and slurry particle migration usually undergoes the process of aggregation‐destruction‐migration‐reassembly. Meanwhile, the influences of pressure, cohesive force, and particle shape on infiltration are also analyzed. The results indicate that high pressure lengthens the infiltration path and increases the infiltration rate. The increase in cohesion enhances the effective clogging of the sand column by the slurry, and particles with smaller sphericity are more likely to clog in the sand column. These findings may enhance our understanding of the slurry infiltration mechanism and its practical application in TBM tunneling. [ABSTRACT FROM AUTHOR]

Two series of experiments were carried out to examine pressurised bentonite slurry infiltration into saturated sand columns. Three types of sand were examined, and water–bentonite and water–bentonite–sand slurries were used in series 1 and 2, respectively. Series 1 investigated the effect of sand particle size and series 2 examined the effect of the fine-sand particle content in the slurry. Scanning electron microscopy (SEM) imaging was used to observe the morphological features of the dry slurry-infiltrated sand samples. A solution for the infiltration distance during mud spurt for water–bentonite–sand slurry infiltration was verified using the data from series 2. The infiltration test results showed that the hydraulic conductivity of the slurry-infiltrated coarse sand for slurry in series 2 was lower than that in series 1. Visual observations and the SEM images showed that sand particles were bound to a bentonite film, indicating that, during infiltration, the channels for fluid flow among the sand particles are blocked by the bentonite particles adhered to the sand particles. The solution for the infiltration distance during mud spurt for water–bentonite–sand slurry infiltration showed good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Over the last 15 years, microbially induced calcite precipitation (MICP) has emerged as a possible solution to mitigate coastal erosion. To date, most MICP soil treatments that have been studied involve column injection using a pump. In recent years, MICP application through surface percolation has gained traction as an alternative technique, but data using this technique are limited. More recently, a new treatment recipe/technique was developed, and this technique was termed bioslurry. Like most MICP studies, research with bioslurry has concentrated on the column injection method, and surface percolation has received very limited attention. This paper discusses the treatment of Florida beach sand by surface percolating bioslurry. Researchers experimented with variations of the bioslurry recipe to optimize erosion resistance, which was assessed using a pocket erodometer combined with physical measurements. In addition, treated specimen morphology was preliminarily examined using X-ray diffraction and scanning electron microscopy. Results showed that erosion resistance was maximized when 15% to 25% of the specimens' pore volumes were filled with bioslurry and that this erosion resistance may be sufficient to withstand worst-case storm events after only one treatment. In addition, previous researchers always used a relatively long (i.e., ∼12 h) stir time when preparing bioslurry. Results presented here show that it may be possible to produce comparable data with much shorter stir times (i.e., 1 to 2 h). [ABSTRACT FROM AUTHOR]

This study aimed to address some basic issues about an air-boosting vacuum consolidation. Through theoretical analysis, it has been clarified that air-boosting pressure is not a consolidation pressure, and the efforts for developing a consolidation theory considering the effect of air-boosting pressure are unnecessary ones. Air-boosting can cause pneumatic fracturing in a soil mass, and equations for estimating the minimum air pressure required have been newly derived based on cavity expansion theories. Then, effects of air-boosting on a vacuum consolidation have been identified as: de-structuring, dewatering, and mitigating apparent clogging around drains. Then, by analyzing some published data of laboratory model tests using clay slurries, it is shown that mitigating apparent clogging contributed to about 30%–60% of the effect of air-boosting (increase settlement), and other part could be the effect of dewatering. Increase air pressure and duration of air-boosting had positive effects on both mitigating apparent clogging and dewatering, but might be more effect on dewatering. • Theoretically clarify an air-boosting pressure is not a consolidation stress. • Equations for estimating minimum required air pressures are newly derived. • Identify three basic effects of an air-boosting on a vacuum consolidation. • Effects of mitigating apparent clogging and dewatering are quantitatively investigated. [ABSTRACT FROM AUTHOR]

As a common industrial valve solution in slurry pipeline systems, Y-type slurry valves must be designed with properly shaped valve seat sealing rings to alleviate particle erosion and keep the valve operating in optimal condition. In this study, we investigate four different valve seat shapes with varying inner angles to understand the effect of the seat structure on particle erosion in Y-type slurry valves. We conducted computation fluid dynamics discrete element method simulations to analyze the impact of different valve seat shapes on the characteristics of particle-liquid two-phase flows and erosion. We also performed a detailed analysis of velocity and pressure distributions for liquid phase and particle velocity distributions as well as surface erosion on key valve components. We observed the primary erosion areas to be the back surface of the valve body, the inner surface of the valve seat, and the front surface of the valve disc, and as a result, we investigated the erosion distribution in these areas with different valve seat structures. Our simulation results indicate that the variation in particle diameter and the inner angle of the valve seat sealing ring have significant impacts on erosion in the studied areas. [ABSTRACT FROM AUTHOR]

In order to solve the technical problems of the super-diameter slurry shield in the waterinrush, sand-bursting and mud-bursting strata at the entrance of the receiving tunnel in the water-rich silt and sand strata near the sea, the differences between the super-diameter and the small-diameter shield in the underwater reception are analyzed by taking the key receiving technology of the super-diameter slurry shield in the water-rich strata of the Shantou Bay Tunnel Project as an example. Based on the receiving process of super-large diameter shield, this paper expounds the solution methods of super-large diameter slurry shield in the aspects of end reinforcement, receiving shaft plugging wall construction, receiving base construction, single-layer glass fiber reinforced concrete tunnel door breaking, penetration measurement, receiving tunneling and grouting, tunnel door plugging, etc., including shield posture control, tunneling parameter control, grouting control, segment re-tightening The key technologies of the super-large diameter shield receiving are analyzed from several aspects of the temporary plugging of the tunnel portal. The mortar receiving base is set to provide sufficient reaction force for the shield receiving to ensure the safety of the shield tunneling. The synchronous grouting and secondary grouting closing is employed to improve the reinforcement quality, strengthen the segment re-tightening and ensure the stability of the shield tunnel structure strength. For the last five rings, special perforated ring segments are used to improve the grouting effect. Then, the drainage and sand removal is carried out, and the reinforcement framework and shotcrete are constructed from top to bottom to block the tunnel door, reduce the exposure time of the tunnel door without blocking, ensure the construction safety of the tunnel door, and other measures are taken to ensure the safety of the underwater reception. [ABSTRACT FROM AUTHOR]

Aiming at the problems such as low settling speed and poor solid-liquid separation effect of a uranium ore high-calcium slurry, static flocculation method was used to settle high-calcium pulp of a uranium ore, and the effects of flocculant type, dosage, mixed flocculant ratio and adding method on the settling effect were investigated. The results show that the settling rate of high calcium pulp can be significantly increased by the mixed flocculant prepared by WZ944 flocculant and 5330 flocculant. The optimal mass ratio of the two flocculants is 1:1, and the minimum dosage of the mixed flocculant is 35 g/t. The research results can provide reference for the optimization design of the uranium ore solid-liquid separation process. [ABSTRACT FROM AUTHOR]

Sizing property of carboxymethyl cellulose nanofiber composite polyacrylate lotion copolymerization size were discussed. A series of nanocomposite polyacrylate emulsion copolymer size CNA was prepared by modifying polyacrylate emulsion copolymer slurry (NA) with carboxymethylcellulose nanofibers (CCNF). The rheological property and sizing performance of the solution were discussed. Study results showed that, within the range amount of CCNF accounted for less than 3% of the solid content of NA size, the solution of NA size and CNA slurry were pseudoplastic fluids. With the increase of CCNF content, the latex particle diameter of CNA slurry showed a decreasing trend, while the apparent viscosity of the solution was increased. Using CNA slurry solution for 9.8 tex and 7.4 tex cotton yarn, under the condition that the sizing percentage was significantly reduced, the sizing performance of CNA slurry solution was still better than the actual sizing production formula of the factory, when the CCNF dosage accounts was 1.5% of the solid content of NA slurry, the comprehensive sizing performance of the prepared CNA slurry was the best. It is considered that CNA slurry has the characteristics of simple pulping, low sizing percentage, excellent sizing performance and easy treatment of desizing wastewater. [ABSTRACT FROM AUTHOR]

To determine the diffusion behavior of a polymer slurry in a narrow slot under a constant pressure head, a relevant simulation model was established based on the theory of a time-varying viscosity, and a visual narrow-slit polymer grouting diffusion model experiment under constant-pressure-head conditions was conducted to verify the accuracy of the established numerical model. On this basis, the effects of the grouting volume, lifting speed, and pressure head on the slurry diffusion behavior (diffusion distance and pressure distribution) were analyzed using the central composite design scheme (response surface method). The results showed that (1) the slurry diffusion range first rapidly increased with increasing grouting volume and then stabilized; (2) with increasing lifting speed of the grouting pipe, the slurry diffusion range first rapidly decreased and then stabilized. when the grouting volume is 0.06 m3, the hydraulic pressure is 0 MPa, the lifting speed is 0 m/s, and the maximum slurry diffusion area is 2.81 m2.; and (3) at the initial stage of the test, the grouting diffusion pressure slowly increased with increasing lifting speed. At the later stage of the test, with increasing lifting speed, the grouting pressure first rapidly increased and then stabilized. [ABSTRACT FROM AUTHOR]

The traditional evaporator of water source heat pump system is easy to freeze when the water source temperature is too low in winter. A novel ice source heat pump system is proposed, which can use low temperature surface water to supply heat to buildings. One of the key problems for safe transportation is velocity range of ice slurry in ice outlet pipeline. In order to study the critical flow velocity of ice slurry in the pipe, an Euler model of horizontal straight pipe and 90° elbow pipe were established by Fluent software. The influence of five factors on the critical flow velocity of two kinds of pipes, including initial ice packing fraction, ice particle size, pipe diameter, length of straight pipe and radius curvature of elbow was studied. It found that the initial ice content should be controlled from 10% to 15%. The inlet flow rate was 20% higher than the critical flow rate under the most unfavorable condition. Ice particle size was less than 0.2 mm. The total length of ice discharge pipeline was less than 50 m. Curvature radius of the bend should be met the minimum requirements of the specification of the pipe used. [ABSTRACT FROM AUTHOR]

3D printing technology provides new ways to complex-shaped ceramic cores forming inner structures in aero-engine blades, but its high-temperature dimensional accuracy is highly impacted by their volume shrinkage and creep deformation. Silica ceramic cores reinforced by mullite fibers were fabricated by 3D printing in terms of vat photopolymerization in this work. Due to the scraper paving the ceramic slurry in 3D printing, majority of the mullite fibers displayed orientation distribution inside the printing layers and decreased the bending strength as the fiber content was below 5 wt%. With 12.5 wt% of mullite fibers, some fibers showed disorder distribution and arranged to connect the interlayer cracks, therefore improving the strength by fiber pull-out. Even though the reinforcement effect of mullite fibers was inadequate, the porosity and leaching rate were significantly improved. Furthermore, the mullite fibers were beneficial to lower shrinkage during sintering and casting, and enhanced the creep resistance due to the high softening temperature, which resulted in enhanced dimensional accuracy. [ABSTRACT FROM AUTHOR]

The research on low-temperature lead-free glass is of great significance for the miniaturization, integration and intelligence of current electronic products, as well as environmental protection. In this article, we report the preparation of low-temperature lead-free B 2 O 3 -BaO-ZnO-SiO 2 -Al 2 O 3 -TeO 2 glasses by a melt-quenching technique. With the increase of TeO 2 content in glass, the glass transition temperature and melting temperature of sintered glass powder decrease, while its wettability and acid corrosion resistance show an increasing trend. The application of glass powder in the sintering experiment of terminal electrode slurry further proves this viewpoint. Compared with the poor sintering performance of the slurry with TeO 2 -free glass powder, the slurry containing TeO 2 glass powder forms a very dense sintered solid, and the sintered slurry is tightly bonded to the ceramic substrate. [ABSTRACT FROM AUTHOR]

The direct ink writing (DIW) technique is considered efficient for manufacturing complex-shaped Cf/SiC composites. However, the SiC slurry with high load has poor flow ability and covering-fibers properties, resulting in numerous gaps between the ceramic matrix and fibers. This study utilized DIW to manufacture Cf/SiC composites and improved the slurry's printing ability by adjusting the binder content. Moreover, the printing parameters, such as the angle between the fiber nozzle and slurry nozzle and the slurry nozzle size, were optimized to enhance the accuracy of the body structure and the filling effect of the slurry on the fiber gaps. The results showed that a binder content of 0.4 wt% produced excellent thixotropic, viscoelastic, and shear thinning behavior in the slurry. By using a fiber nozzle angle of 60° and a nozzle diameter of 1.55 mm, the slurry effectively filled the gaps between the fiber bundle and matrix, reducing the number and size of pores in the SiC matrix. These improvements greatly enhance the density, strength, and fracture toughness of the Cf/SiC composites. Therefore, this research demonstrated that optimizing the printing parameters not only improved the structural accuracy of the printed bodies but also greatly enhanced the properties of the ceramic matrix composites. [ABSTRACT FROM AUTHOR]

Reticulated ceramic filters play an important role in the reduction of non-metallic inclusions in molten steel, which can improve the quality of steel products. In this work, periclase-magnesium aluminate spinel ceramic filters with Al 2 O 3 and TiO 2 functional coatings were fabricated by using microporous MgO powder, respectively. The effects of the functional coatings on their microstructure, properties and purification capacity on molten steel were studied. The filter with Al 2 O 3 functional coating exhibited the best mechanical properties owing to the good rheological properties of the coating slurry, as well as the formation of in-situ spinel layer connection between the Al 2 O 3 functional coating and the microporous MgO layer of the filter substrate. Compared with the filters without functional coating or with TiO 2 functional coating, the filter with Al 2 O 3 functional coating made more Al 2 O 3 inclusions deposit on the filter surface by physical adsorption due to the same chemical composition between the functional coating and inclusions, which significantly improved the adsorption capacity of filter for Al 2 O 3 inclusions in molten steel. Overall, the filter with Al 2 O 3 functional coating had the highest cold compressive strength of 1.4 MPa, a residual retention of cold compressive strength after thermal shock of 65.71 % and an efficiency of 36.56 % in reducing the total oxygen content of the steel. [ABSTRACT FROM AUTHOR]

Field-applied liquid animal manure (slurry) is a significant source of ammonia (NH3) emission, which is harmful to the environment and human health. To evaluate mitigation options, reliable emission measurement methods are needed. A new system of dynamic flux chambers (DFCs) with high-temporal-resolution online measurements was developed. The system was investigated in silico with computational fluid dynamics and tested using three respective field trials, with each trial assessing the variability in the measured emission after application with trailing hose at different scales: manual (handheld) application, a 3 m experimental slurry boom, and a 30 m farm-scale commercial slurry boom. For the experiments with machine application, parallel NH3 emission measurements were made using an inverse dispersion modeling method (backward Lagrangian stochastic, bLS, modeling). The lowest coefficient of variation among replicate DFC measurements was obtained with manual application (5 %), followed by the 3 m slurry boom (14 %), and lastly the 30 m slurry boom (20 %). Conditions in DFCs resulted in a consistently higher NH3 flux than that measured with the inverse dispersion technique, but both methods showed a similar emission reduction by injection compared with the trailing hose: 89 % by DFC and 97 % by bLS modeling. The new measurement system facilitates NH3 emission measurement with replication after both manual and farm-scale slurry application with relatively high precision. [ABSTRACT FROM AUTHOR]

Polycarboxylate superplasticizers BMC-L and BMC-S were utilized as modifiers in the formulation of novel cement-based grouting materials. Indoor tests were conducted on 32 groups of cement slurries, varying by water–cement ratio (0.5:1 and 0.6:1) and modifier content (0, 2‰, 4‰, 6‰, 8‰, 10‰, 12‰, and 14‰), to test their density, funnel viscosity, water separation rate, and stone rate. Four groups of slurry modified with BMC-L were selected as the preferred slurry, and the apparent viscosity test, uniaxial, and triaxial compression test of the slurry stone body were conducted. The study investigated the influence of BMC-L on various properties of the slurry, including its apparent viscosity, uniaxial compressive strength, stress–strain relationships, shear strength parameters, and elastic modulus. Ultimately, the pore structure and phase composition of the slurry stone body were detected by Nuclear Magnetic Resonance (NMR) and X-ray Diffraction (XRD), and the impact of BMC-L on slurry performance was examined from a microstructural perspective. Results indicate that the two polycarboxylate superplasticizers exert minimal influence on the density and water separation rate of the slurry. Within the effective incorporation range of the polycarboxylate superplasticizer, increasing the dosage correlates with a decrease in both the stone rate and viscosity of the slurry. BMC-L significantly enhances the mechanical properties of the slurry stone body by promoting more complete cement hydration and reducing porosity. The uniaxial compressive strength of slurry stone body with a 6 ‰ BMC-L dosage reached 29.7 MPa after 7 days and 38.5 MPa after 28 days of curing, representing increases of 118.4% and 64%, respectively, compared to masonry with 0 BMC-L dosage. The shear strength parameters and elastic modulus of the slurry stone body also showed corresponding increases. [ABSTRACT FROM AUTHOR]