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Alloy phase change materials (PCM) are key materials in latent heat storage systems for solar thermal power generation, however, their application is limited by the high corrosion and oxidation problems of alloys. To reduce the erosion problem of alloy PCM, SiC-based ceramic encapsulated flake graphite (EG) modified Al-Cu28-Si6 alloy was used to successfully prepare composite PCM with high compatibility and oxidation resistance. Adopting static erosion test method, the composite PCM was subjected to 50 thermal cycles (25–1000 °C holding time of 10 h was recorded as 1 cycle). The results showed that SiC-based ceramics have excellent corrosion resistance to composite PCM with 10 wt% EG added, which due to the excellent reticulation and encapsulation of EG. Based on the Young-Laplace equation and the contact angle, the erosion resistance mechanism of silicon carbide ceramic alloys has been revealed. SiC-based ceramic-PCM sensible heat-latent heat composite heat storage material was expected to be used for high-temperature heat storage in solar thermal power generation. [ABSTRACT FROM AUTHOR]

Coatings are utilized to enhance the surface properties of materials. This study aimed to modify the TiN coating with a novel sandwich-zigzag intermediate layer and delve into the intricate damage mechanisms under harsh corrosion-erosion coupling environments. Due to the infiltration of NaCl into the coating and the subsequent formation of TiO 2 , the sandwich-zigzag TiN coatings exhibited a reduction in mechanical behavior and erosion resistance when exposed to salt spray at 550 °C for 50 h. Moreover, the erosion rates of the as-corroded TiN coatings displayed an opposite trend compared to that of the as-deposited coatings, showing that the erosion rate was highest at the erosion angle of 30°. Nevertheless, the presence of the zigzag-TiN intermediate layer benefited the coating by preventing stress accumulation and heterogeneous interface. This ultimately improved the erosion resistance of the coatings by more than 2 times at universal erosion angle compared to that of the substrates under the synergistic effects of corrosion and erosion. [ABSTRACT FROM AUTHOR]

Dense γ-Y 2 Si 2 O 7 /Y 2 O 3 –SiO 2 –Al 2 O 3 glass coatings were prepared on porous Si 3 N 4 ceramics using high-temperature melt-infiltration preparation method to improve their stability in service environments, specifically including water resistance and erosion wear resistance. Evolution of structure and mechanical properties during coating preparation was studied. Damage mechanism in erosion wear process was illustrated by putting the coated samples into a high-speed water flow with quartz particles. Dense double-layer microstructure could be formed when sintering at 1350–1450 °C for 1 h. The proportion of each phase inside the coating material prepared by various sintering temperatures was different, resulting in different elastic modulus and hardness, and ultimately affected the erosion resistance of the coatings. The "plasticity index" (E/H value) of γ-Y 2 Si 2 O 7 /Y 2 O 3 –SiO 2 –Al 2 O 3 glass coating prepared at lower temperature (1350 and 1400 °C) was low, and the erosion failure of the coating was brittleness mode, leading to an obvious decrease on waterproof performance after erosion test. While coating prepared at higher temperature (1450 °C) showed a better erosion resistance. After erosion for 2 h, water absorption of coating surface was changed by only 1.34 %. Micro-morphology of the coating was almost unchanged before and after erosion, maintaining excellent waterproof performance. [ABSTRACT FROM AUTHOR]

This study investigates the effectiveness of Microbially Induced Calcite Precipitation (MICP) technology in enhancing the stability of aeolian sand. Applying MICP to desert sand samples from Kashi, Xinjiang, the results demonstrated significant structural stability and erosion resistance in treated soils during wind erosion tests. Particularly after 14 days of treatment, the soil samples exhibited optimal wind erosion resistance and surface crust strength. Additionally, the formation of calcite significantly improved the soil's penetration strength and wind erosion resistance, with SEM analysis confirming that calcite "bridges" between soil particles enhanced inter-particle bonding. Environmental impact assessments indicated that MICP technology is not only environmentally friendly but also effectively reduces the risk of soil environmental pollution. These findings validate the potential application of MICP technology in enhancing the stability and environmental adaptability of aeolian sand. [ABSTRACT FROM AUTHOR]

Loess has high water sensitivity and exhibits poor characteristics such as weak cementation and high porosity. Under heavy rainfall, loess fill slopes are prone to erosion and landslides, posing serious threats to public safety and property. In light of these serious threats, this study employed the method of spraying polyvinyl alcohol (PVA) solution to improve loess fill slopes and systematically examine its protective effects. Through field investigations and combined laboratory and outdoor tests, this study comprehensively evaluated the mechanical properties, anti-aging and anti-erosion performance of loess after PVA solution spraying. Scanning electron microscopy was used to reveal the mechanism of PVA action at the microscopic level. The results showed that after treatment with PVA solutions of varying concentrations, the mechanical properties of loess samples were significantly enhanced, while also exhibiting excellent anti-aging and water resistance performance. Additionally, PVA-treated loess fill slopes exhibited excellent rain erosion resistance. A microscopic structural analysis showed that PVA fills the internal pores of loess, strengthens inter-particle bonding, and uses its hydrophobic groups' water-repellent action to effectively enhance slope stability and erosion resistance. In conclusion, PVA treatment not only significantly enhances the protective effects of loess fill slopes but also holds important value in improving soil sustainability and environmental protection. [ABSTRACT FROM AUTHOR]

This study looks at how erosive wear affects hybrid composites made by vacuum infusing glass and basalt fibers into an epoxy matrix. The study uses garnet abrasives and a design experiment method to test how resistant these hybrid composites are to erosion at 30°, 60°, and 90° angles of impact. The analysis included three‐dimensional profilometry and scanning electron microscopy. Results show that glass layers enhance erosion resistance, whereas basalt layers increase wear. Key quantitative findings include erosion rates and mass loss, highlighting impingement angle and erosion time as critical factors. At a 30° angle, basalt exhibited more severe wear (erosion rate: 0.8090 mg/g for 20 s) compared to glass (erosion rate: 0.5683 mg/g). Conversely, at 90°, the erosion rate for basalt decreased to 0.3643 mg/g, indicating a decreased sensitivity to this steeper angle. According to the ANOVA, impingement angle and erosion time account for 30.08% and 50.25% of the erosion rate variance, respectively. These findings advance our understanding of material behavior in hybrid composites and emphasize the strategic selection and layering of materials for enhanced durability. This research contributes to developing more sustainable composites, demonstrating natural fibers' potential to improve mechanical properties and erosion resistance. Highlights: Glass layers enhance durability against erosive forces in hybrid composites.Basalt layers accelerate erosion rates, showing a need for strategic layering.Glass fiber reinforcement significantly improves wear performance.Hybrid constructions with glass a top basalt balance flexibility and durability.Emphasizes eco‐friendly advantages of natural materials in composites. [ABSTRACT FROM AUTHOR]

AbstractThe current investigation examines the wear performance of High-Velocity Oxygen Fuel coated Colmonoy-88 coating on SS 304. An L9 orthogonal array design based on the Taguchi fractional factorial method was used to create the erosive wear tests. The impact of three parameters, such as impact velocity (100, 120, and 140 m/s), angle of impact (30°, 60°, and 90°), and test duration (10, 15 and 20 min), on wear performance was investigated by analysis of variance. Results show that the impact angle is the most vital factor for mass loss in both SS 304 and Colmonoy-88, followed by impact velocity and time duration. It was revealed that the maximum wear takes place at 30° impact angle in both specimens. The outcomes of the XRD and EDS analysis show that the Colmonoy-88 has a high chromium content, which provides it with exceptional erosion resistance. The Colmonoy-88 wear mechanism involved inter-splat micro-cutting, lips, crack initiations, and craters caused by fly ash particles at varying impact angles. [ABSTRACT FROM AUTHOR]

In order to solve the severe erosion of kiln refractories for the high‐temperature treatment used during the process of recovering valuable metal elements from waste lithium batteries, this study investigates the low‐cost, no‐firing preparation technology of erosion‐resistant SiC–C–t‐ZrO2 composites with self‐prepared t‐ZrO2–SiC–C powder, as well as silicon carbide and flake graphite as the main raw materials, and phenolic resin as the binding agent. (1) The effects of different t‐ZrO2–SiC–C powder additions and heat treatment temperatures on the properties of SiC–C–t‐ZrO2 composites were studied in details. (2) The erosion resistance of SiC–C–t‐ZrO2 composites to after‐use lithium battery waste was evaluated using the static crucible method. The mechanical properties of the t‐ZrO2–SiC–C composites was the best that its cold modulus of rupture (CMOR) was 11.37 MPa and cold crush strength (CCS) was 41.96 MPa when heat treatment temperature was 600°C and content of t‐ZrO2–SiC–C powder was 10 wt%. At that condition, the bulk density of samples reached to 3.15 g/cm3 and apparent porosity of it was only at 11.09% which means that the samples designed in this work are compacted enough. In the erosion test, the t‐ZrO2–SiC–C composites had an excellent resistance to erosion of lithium battery waste. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the effectiveness of Microbially Induced Calcite Precipitation (MICP) technology in enhancing the stability of aeolian sand. Applying MICP to desert sand samples from Kashi, Xinjiang, the results demonstrated significant structural stability and erosion resistance in treated soils during wind erosion tests. Particularly after 14 days of treatment, the soil samples exhibited optimal wind erosion resistance and surface crust strength. Additionally, the formation of calcite significantly improved the soil’s penetration strength and wind erosion resistance, with SEM analysis confirming that calcite “bridges” between soil particles enhanced inter-particle bonding. Environmental impact assessments indicated that MICP technology is not only environmentally friendly but also effectively reduces the risk of soil environmental pollution. These findings validate the potential application of MICP technology in enhancing the stability and environmental adaptability of aeolian sand.

Abstract Highway shoulder rocks are exposed to continuous erosion force due to extreme rainfall that could be caused by global warming to some extent. However, the logical design method for erosion-resistant highway shoulder is not well-researched yet. This study utilized a large-scale UNLETB (University of Nebraska Lincoln–Erosion Testing Bed) with a 7.6 cm nozzle width and a 4000 cm3/sec flow rate to study the erosion characteristics of highway shoulder rocks. Test results showed that different shoulder materials currently used had vastly diverse erosion resistance. However, the clear criteria between the erosion-resistant gradation and other gradation could not be determined easily. Then, this study trained ANN (Artificial Neural Network) with test results to conveniently distinguish the erosion resistance of rocks from other rocks. The ANN predicted the acceptable/non-acceptable erosion characteristics of shoulder rocks with close to 99% accuracy based on the three gradation parameters (D10, D30, and D60).

Since Chernozems are among the most fertile soils in the world, the study of their degradation is of great interest. However, the microstructure and composition of the soil organic matter (SOM) in eroded Chernozems have not yet been sufficiently studied. We studied the SOM and aggregate states of eroded Chernozems using the example of two catenas with arable Haplic Chernozems in the Kursk region of Russia. In the plow horizons (the part of the soil most susceptible to water erosion), we determined the mean-weighted aggregate diameter (MWD), structure and water stability coefficients (SC and WS; dry and wet sieving, respectively), soil organic carbon (SOC) content, and SOM composition and content (qualitative and quantitative micromorphological analyses, respectively). It was shown that with an increase in the degree of erosion, the content of SOC decreased significantly, according to both chemical and micromorphological methods of evaluation. No significant relationships were found between the degree of erosion and the indicators of the structure (except for WS, which was significantly lower in non-eroded Chernozem than in slightly and moderately eroded soils). With the increasing degree of erosion, the humus state of these soils deteriorates at the microlevel, the intensity of humification decreases, the depth of the appearance of assimilated biogenic aggregates with finely dispersed calcite in the profile increases, the structure is destroyed, lumpy aggregates form, and the proportion of planar voids increases. The downslope transport of the soil solid phase under the impact of erosion is accompanied by the accumulation of the transformation products of carbohydrates in the Chernozems in the lower part of the catena. In the Chernozems located in the transit position of the slope, the composition of SOM is characterized by the predominance of lipids and nitrogen-containing compounds. Our unique results contribute to a deeper understanding of the formation of structure and water resistance in eroded soils. [ABSTRACT FROM AUTHOR]

Sand solidification of earth-rock dams is the key to flood discharge capacity and collapse prevention of earth-rock dams. It is urgent to find an economical, environmentally friendly, and durable sand solidification technology. However, the traditional grouting reinforcement method has some problems, such as high costs, complex operations, and environmental pollution. Enzyme-induced calcium carbonate precipitation (EICP) is an anti-seepage reinforcement technology emerging in recent years with the characteristics of economy, environmental protection, and durability. The erosion resistance and shear strength of earth-rock dams solidified by EICP need further verification. In this paper, EICP-solidified standard sand is taken as the research object, and EICP-cemented standard sand is carried out by a consolidated undrained triaxial test. A two-stage pouring method is adopted to pour samples, and the effects of dry density, cementation times, standing time, and confining pressure on the shear strength of cemented standard sand are emphatically analyzed. The relationship between cohesion, internal friction angle, and CaCO3 formation was analyzed. After the optimal curing conditions are obtained through the triaxial shear strength test, the erosion resistance model test is carried out. The effects of erosion angle, erosion flow rate, and erosion time on the erosion resistance of EICP-solidified sand were analyzed through an erosion model test. The results of triaxial tests show that the standard sand solidified by EICP exhibits strain softening, and the peak strength increases with the increase in initial dry density, cementation times, standing time, and confining pressure. When the content of CaCO3 increases from 2.84 g to 12.61 g, the cohesive force and internal friction angle change to 23.13 times and 1.18 times, and the determination coefficients reach 0.93 and 0.94, respectively. Erosion model test results indicate that the EICP-solidified sand dam has good erosion resistance. As the increase in erosion angle, erosion flow rate, and erosion time, the breach of solidified samples gradually becomes larger. Due to the deep solidification of sand by EICP, the development of breaches is relatively slow. Under different erosion conditions, the solidified samples did not collapse and the dam broke. The research results have important reference value and scientific significance for the practice of sand consolidation engineering in earth-rock dams. [ABSTRACT FROM AUTHOR]

This paper found that environmentally friendly guar gum biopolymers are helpful for stopping the erosion of basalt residual-soil shallow slopes, while also improving the problems of poor stability, difficult growth of early vegetation, and weak initial resistance to the rainfall scouring of these slopes under extreme climatic conditions. Then, to illustrate the effects of the guar gum treatment, laboratory tests have been conducted, including a soil strength test, water retention and water absorption tests, a disintegration test, and a simulated rainfall erosion test, and the pattern of its effect on vegetation growth has been explored. The results indicate that as the content of guar gum increases, both the cohesion and angle of internal friction exhibit a trend of first increasing and then decreasing; the angle of internal friction varies within a range of 21° to 26°. The evaporation rate, water absorption rate, and disintegration rate of this guar gum-treated soil were significantly reduced, while the cracking of the surface layer was significantly improved. The disintegration rate of the soil is only about 2%, as the guar gum content is greater than 1%. Moreover, there is no sign indicating that vegetation germination was affected by the guar gum, meaning that it maintains a favorable environment for vegetation to grow. Guar gum-cured slopes were significantly protected under heavy rainfall washout conditions, with a 94.85% reduction in total soil loss from the slope surface compared to untreated slopes. Since the pores of soil are filled with guar gum hydrogel, the erosion resistance of soil is greatly enhanced. The results of this study will provide a scientific basis for engineering the protection of shallow slopes of basalt residual soils. [ABSTRACT FROM AUTHOR]

Highway shoulder rocks are exposed to continuous erosion force due to extreme rainfall that could be caused by global warming to some extent. However, the logical design method for erosion-resistant highway shoulder is not well-researched yet. This study utilized a large-scale UNLETB (University of Nebraska Lincoln–Erosion Testing Bed) with a 7.6 cm nozzle width and a 4000 cm3/sec flow rate to study the erosion characteristics of highway shoulder rocks. Test results showed that different shoulder materials currently used had vastly diverse erosion resistance. However, the clear criteria between the erosion-resistant gradation and other gradation could not be determined easily. Then, this study trained ANN (Artificial Neural Network) with test results to conveniently distinguish the erosion resistance of rocks from other rocks. The ANN predicted the acceptable/non-acceptable erosion characteristics of shoulder rocks with close to 99% accuracy based on the three gradation parameters (D10, D30, and D60). [ABSTRACT FROM AUTHOR]

This study aims to synthesize TiC + TiB2 reinforced epoxy/glass fiber composites to enhance mechanical properties and resistance to wear and erosion. For this purpose, TiC + TiB2 particles were added to the epoxy matrix in contents of 0, 2.5, 5, 12.5, and 20 wt.%, and the composites were then created through the hand-layout technique. The mechanical, wear, and erosion properties were eventually analyzed. The wear mechanisms of samples were evaluated by scanning electron microscope (SEM) images. The findings indicated that adding 2.5 wt. % of particles maximized the modulus, increasing the tensile and flexural modulus rates by 26 and 17%, respectively. The hardness also improved when TiC + TiB2 particles were added. In fact, it reached the maximum level (58%) once 12.5 wt.% of particles were added. The wear resistance of the composites increased with the TiC + TiB2 content where adding 20 wt.% of the particles enhanced the abrasion resistance by 86% while lowering the friction coefficient. The erosion resistance was analyzed with a rotating device in an abrasive slurry under different variables such as rotation speed, impact angle, and sand rate. The maximum erosion resistance was observed in a composite sample containing 12.5 wt.% of TiC + TiB2 particles. [ABSTRACT FROM AUTHOR]

In order to study the influence of the bond coat on the erosion resistance of the thermal barrier coating (TBC), two different bond coats (NiCrAlY and NiCoCrAY) were deposited onto Inconel 718 substrate by using Atmospheric Plasma Spray (APS). After that topcoat Yttria Stabilized Zirconia with the Y2O3 content of 8 weight % (8YSZ) coatings were deposited by APS method onto the bond coats also. Alternative test rig compliant with the ASTM G211-14, was used in experiments. These experiments were performed at three different air temperatures (21°C, 300°C and 600°C), three different erosive particle impact angles (30°, 60° and 90°), constant particle impact velocity (~97 m/s) and particle size (400 µm Al2O3) after which, the erosion rate-impact angles results were obtained. Scanning electron microscopy (SEM) images, X-ray diffraction (XRD) analysis, Energy dispersive X-ray (EDX) mapping and EDX elemental analysis were conducted to assess the effectiveness of bond coating and ceramic topcoats to reduce wear at high temperatures. The importance of adhesion at the interface between bond coatings and ceramic topcoats was determined. However, erosion resistance generally increased with temperature, and this resistance effect tended to decrease with the presence of Cobalt. [ABSTRACT FROM AUTHOR]

Ice accumulation on lift-generating surfaces, such as rotor blades or wings, degrades aerodynamic performance and increases various risks. Active measures to counteract surface icing are energy-consuming and should be replaced by passive anti-icing surfaces. Two major categories of surface treatments—coating and structuring—already show promising results in the laboratory, but none fulfill the current industry requirements for performance and durability. In this paper, we show how femtosecond laser structuring of stainless steel (1.4301) combined with a hydrocarbon surface treatment or a vacuum treatment leads to superhydrophobic properties. The anti-ice performance was investigated in an icing wind tunnel under glaze ice conditions. Therefore, flexible steel foils were laser-structured, wettability treated and attached to NACA 0012 air foil sections. In the icing wind tunnel, hydrocarbon treated surfaces showed a 50 s ice build-up delay on the leading edge as well as a smoother ice surface compared to the reference. To demonstrate the erosion resistance of these surfaces, long-term field tests on a small-scale wind turbine were performed under alpine operating conditions. The results showed only minor erosion wear of micro- and nano-structures after a period of six winter months. [ABSTRACT FROM AUTHOR]

In most coastal and estuarine areas, tides easily cause surface erosion and even slope failure, resulting in severe land losses, deterioration of coastal infrastructure, and increased floods. The bio-cementation technique has been previously demonstrated to effectively improve the erosion resistance of slopes. Seawater contains magnesium ions (Mg2+) with a higher concentration than calcium ions (Ca2+); therefore, Mg2+ and Ca2+ were used together for bio-cementation in this study at various Mg2+/Ca2+ ratios as the microbially induced magnesium and calcium precipitation (MIMCP) treatment. Slope angles, surface strengths, precipitation contents, major phases, and microscopic characteristics of precipitation were used to evaluate the treatment effects. Results showed that the MIMCP treatment markedly enhanced the erosion resistance of slopes. Decreased Mg2+/Ca2+ ratios resulted in a smaller change in angles and fewer soil losses, especially the Mg2+ concentration below 0.2 M. The decreased Mg2+/Ca2+ ratio achieved increased precipitation contents, which contributed to better erosion resistance and higher surface strengths. Additionally, the production of aragonite would benefit from elevated Mg2+ concentrations and a higher Ca2+ concentration led to more nesquehonite in magnesium precipitation crystals. The slopes with an initial angle of 53° had worse erosion resistance than the slopes with an initial angle of 35°, but the Mg2+/Ca2+ ratios of 0.2:0.8, 0.1:0.9, and 0:1.0 were effective for both slope stabilization and erosion mitigation to a great extent. The results are of great significance for the application of MIMCP to improve erosion resistance of foreshore slopes and the MIMCP technique has promising application potential in marine engineering.

Abstract Rammed earth is a kind of cleaning material, widely used in all kinds of buildings in the world. The Great Wall of ancient China is a typical world cultural site built from rammed earth. The rammed earth Great Wall of Shanhaiguan is close to Bohai Bay, which has suffered from long-term erosion by rain, causing a series of problems such as soil loss, collapse and gully flushing. The protection materials of the rammed earth site have always puzzled scholars. However, during the rainy season, it was found that some of the walls at Xiaowan Gouge and Nantuzhuang Gouge in the Shanhaiguan Great Wall had unwashed traces, the soil surface of the walls was intact, and the anti-erosion ability of the walls was significantly higher than that of other places. In order to explore the reasons for its strong anti-erosion ability in the natural state of rammed earth wall, guide the protection of rammed earth Great Wall, and carry out different experimental tests to explore its anti-erosion reasons and internal mechanisms. Firstly, the characteristics of rammed soil were understood through the composition test of rammed soil, and the indoor and outdoor erosion test was carried out to determine that the anti-erosion reason was the protection of gray-green soil crust. The property and composition of soil crust were determined through the immersion test and genome sequencing. Finally, the protection mechanism of soil crust was analyzed by scanning electron microscopy.

Synergistically enhancing the erosion and impact resistance of contacts poses a significant challenge for cutting-edge electrical equipment. Fortunately, mollusk shells in nature have evolved effective strategies to construct microstructures with superior erosion and impact resistance. Inspired by the structure of nacre, AgSnO2 contact material with hierarchical architectures has been designed and fabricated. The mechanistic link between microstructural evolution and dynamic erosion is studied through experiments combined with Computational Fluid Dynamics (CFD) and Finite Element Method (FEM) simulations. Results show that the reconstructed SnO2 skeleton endowed with a highly continuous and anisotropic ‘flowering'-like structure forms a continuous interpenetrating network with Ag, optimizing the conductive pathways on the molten pool surface. Additionally, the Ag-rich regions in the deeper layers on both sides of the molten pool offers a stable ‘nutrient-supply’ for the continuous ‘flowering’ reconstruction of the skeleton, exhibiting excellent in-situ self-repairing erosion resistance. Benefiting from this synergistic strategy, this skeleton is reconstructed based on its natural structure, which further disperses the stress and deformation concentration while inhibiting interfacial debonding, thereby reducing the formation of cracks and significantly enhancing the impact resistance. This work is expected to breakthrough erosion and impact resistance in extreme condition electrical contact materials through biomimetic microstructure design.

The present work is focused on investigating the mechanical, thermal, and electrical erosion resistance properties of newly developed silicone rubber composites with micro-size-low melting glass powder (LMGP) and nano-size alumina trihydride (n-ATH). Utilizing the fluorescent fiber, a new erosion testing method has been developed. The intensity of the signal generated from the fluorescent fiber explains the severity of damage caused by electrical inception followed by arcing and erosion. LMGP filler exhibits good thermal stability, arc resistance, and flame-retardant properties by forming a ceramic structure between ATH and silicone rubber matrix. With ATH/LMGP-filled hybrid samples, the formation of fire cinders is observed rather than flame formation in virgin silicone rubber samples at the time of erosion. Very little temperature rise is observed at the time of erosion with the LMGP-added samples. Compared to virgin material, the hybrid composite material shows a mechanical improvement of 13.03% in tensile strength and 12.47% in tear strength. The synergetic effect of the ATH and LMGP fillers enhances the thermal conductivity of the silicone rubber matrix by 59.34%. FEM studies revealed the basic understanding of the local hotspot reduction with the addition of high thermal conductive fillers and its effect on erosion resistance. [ABSTRACT FROM AUTHOR]

Understanding the erosion characteristics of different pipe materials is of paramount importance in the field of pipeline transportation due to its critical role in maintaining operational efficiency and safety. However, erosion caused by entrained particles during fluid flows poses a significant challenge to pipeline integrity. This study employs Computational Fluid Dynamics (CFD) to comprehensively analyze and compare the erosion behaviors of stainless steel XS80S and steel XS80 pipes with 90° elbows. The investigation focuses on turbulent oil and sand particle transportation conditions, enabling the prediction of erosion rate distribution and particle trajectories, particularly within the elbow region. The results highlight the superior erosion resistance of stainless steel XS80S over steel XS80 across various simulation models. The study underscores the significance of material selection in combating erosion and enhancing pipeline integrity. The XS80S pipes performed better than the XS80 Pipes. The maximum Dpm Erosion Rate Finnie model for the XS80S and XS80 pipes were 8.62 E-25 mm3 kg-1 and 9.17 E-25 mm3 kg-1, respectively; for the McLaury model they were 2.94E-24 mm3 kg-1 and 3.10E-24 mm3 kg-1, respectively; for the Oka model they were 5.68E-26 mm3 kg-1 and 6.75E-26 mm3 kg-1, respectively. The maximum Dpm Accretion Rate for the XS80S and XS80 pipes were 2.01E-17 mm3 kg-1 and 2.06E-17 mm3 kg-1, respectively. Furthermore, the investigation sheds light on the vulnerabilities of the elbow region within pipelines, providing insights into targeted design modifications and maintenance protocols. This research advances the understanding of erosion mechanisms, fluid dynamics, and material performance, offering actionable insights for pipeline industry stakeholders. The findings lay the groundwork for future research avenues and contribute to the evolution of corrosion management practices. [ABSTRACT FROM AUTHOR]

Low hardness and high abradability are often required for abradable seal coating (ASC) to protect the blade tip of gas turbines and aeroengines. However, the low bonding strength often lead to spallation failure. In this paper, a novel abradable seal coating with thin-wall porous spheres was designed and prepared. Results show that this coating has both a low hardness of 48.6 HR15Y and a high bonding strength of 25.4 MPa. The abradability and erosion resistance of this coating are 4 times and 63 times higher than reported metal-based coatings. In addition, no surface densification occurs after incursion due to the novel abradable mechanism of crushing of thin-wall sphere. This demonstrates the coating can retain excellent abradability during service and have a long lifetime. The combination of durable excellent abradability and adhesive strength contribute to a long lifetime required by next-generation gas turbines and aeroengines towards higher efficiency and reliability. [ABSTRACT FROM AUTHOR]

Biochar has widespread benefits and is widely used in multidimensional spheres, including agronomy, environmental management, and geoengineering. The present review attempts to discuss the already established and possible futuristic application of biochar as a soil amendment in geoengineering applications (green slopes, landfill liner). To assess the role of biochar in geoengineering, about 180 studies were randomly taken from 1996 to 2020. The snowball technique was used to collect research papers and parameters. The main focus was to analyze critical gaps in research done on biochar use in geoengineering applications for soil stabilization. It was observed that biochar production and application are still limited to the laboratory and need research on a larger scale. There are contradictory observations in various properties of biochar, e.g., biochar's addition increases the water retention capacity of the soil, but some researchers suggest otherwise. Also, the stability factors of landfill slopes viz shear strength, compressibility, and tensile strength are not brought out clearly. The cost-effectiveness of biochar production and application is also a major concern. Future research needs to be conducted to tackle the negative impacts of biochar, such as strength and long-term efficiency. Further, the in-situ application of biochar in compacted engineered soils needs to be investigated. Preliminary guidelines for selecting a suitable and optimal percentage of biochar with specifications need to be formulated for application in green engineering infrastructure. It was found that there is a lack of information about the availability and properties of biomass-based feedstock, its cost-effectiveness for preparation, application, and life span of biochar in comparison to other alternatives of soil stabilization. [ABSTRACT FROM AUTHOR]

The sand-bearing natural gas causes severe erosion to the components of wellhead desanders，thereby reducing production efficiency and posing safety hazards.Aiming at the serious erosion problem of key parts in desanders，the study focused on the erosion resistance of erosion resistance materials such as 42CrMo，45 steel，2Cr13，20CrMnTi，and H13 (4Cr5MoSiV1) from perspectives of erosion angle and heat treatment effects.Firstly，an erosion test platform was established to conduct erosion simulation tests.Secondly，the micro-morphology of the target materials after erosion was observed using scanning electron microscope (SEM)，and the erosion wear mechanisms were discussed.Results showed that for erosion angles between 30° and 90°，the erosion rate decreased as the angle increased.It was also found that not all materials showed improved erosion resistance following heat treatment.The erosion resistance of 2Cr13 in the quenched and tempered state was the best.The wear mode of 2Cr13，45 steel in quenched and tempered state and H13 steel in factory state during oblique impact was mainly cutting，while the wear mode during vertical impact was abrasive impact，which caused plastic deformation and detachment of the target materials.This experiment provided a reference for selecting corrosion-resistant components in desanders.

High-temperature stable thermal storage materials are urgently needed to meet the demand for solar thermal power generation. Herein, Cu–20Si alloy-corundum ceramic composite thermal storage materials are prepared. The thermal storage performance of the composite, and the erosion resistance of ceramic matrix to alloy are investigated during high-temperature (1000 °C) service for 1000 h. The results show that the latent heat of Cu–20Si alloy is increased by 130.76 % to 201.2 kJ/kg compared with the original. Meanwhile, the alloy forms a dense transition layer on the ceramic matrix surface by melting and spreading. Furthermore, the ceramic matrix shows superior erosion resistance to the alloy, owing to the dense structure of ceramic and no chemical reactions between the alloy and ceramic matrix. Finally, test results of long-time service confirm the stability of the composite, which can be used stably for high temperature thermal storage. [ABSTRACT FROM AUTHOR]

Industrial waste has a high potential for reuse in the production of refractories, which can significantly lower costs. The purpose of the research is to access the role of three types of recycled industrial wastes (ferro‐titanium slag [FTS], ferhro‐chromium slag [FCS], and ferro‐vanadium slag [FVS]) utilized as aggregate in the traditional Al2O3‐SiC‐SiO2‐C refractories (ASSC). Erosion and corrosion resistance characterization was performed to determine whether these industrial waste‐containing ASSC still perform better than traditional ASSC during service. Based on the results, incorporating FVS into the ASSC was not recommended, its corrosion resistance was significantly reduced due to the presence of excessive liquid phase. Nonetheless, FTS and FCS could be added as aggregate to the ASSC without affecting their performance. This necessity of the proper amount of liquid phase in ASSC was highlighted in this research since the parameters could alter its properties. Furthermore, the Ti(C,N) transformed from TiO2 in FTS via carbothermal reduction nitridation could effectively prevent further corrosion, and Cr2O3 derived from the decomposition of (Al,Cr)2O3 solid solution in FCS could play the same role during the corrosion process, both of which may be potential raw materials to be used in refractories. [ABSTRACT FROM AUTHOR]

Two-dimensional carbon/carbon (2D C/C) composites are a special class of carbon/carbon composites, generally obtained by combining resin-impregnated carbon fiber clothes, which are then cured and carbonized. This study deals with the preparation of a protective coating for these materials. This coating, based on graphite, was prepared by the slurry method. The effect of graphite and phenolic resin powders with different weight ratios was examined. The results have shown that the coating slurry can fill the pores and cracks of the composite surface, thereby densifying the surface layer of the material. With the increase of the graphite powder/phenolic resin weight ratio, the coating density is enhanced while the coating surface flatness decreases; moreover, the protective ability of coating against erosion first increases (from 1:3 to 2:2) and then decreases (from 2:2 to 3:1). When the weight ratio is about 1:1, the coating for 2D C/C composites exhibits the best erosion resistance, which greatly aids these materials during gas quenching. In this case, the erosion rate is decreased by approximately 41.5% at the impact angle of 30° and 52.3% at normal impact, respectively. This can be attributed to the ability of the coating slurry to infiltrate into the substrate, thereby bonding the fibers together and increasing the compactness of the 2D C/C composites. [ABSTRACT FROM AUTHOR]

Soil curing agents PAAB and PAAH were prepared from butyl acrylate (BA), acrylic acid (AA) and styrene (st) as main monomers by grafting humic acid (HA). Their structures were characterized and their application properties were tested. The results show that: (1) the synthesized emulsion is stable and the particle size distribution is uniform; (2) The solidified soil/water contact Angle, the stability of aggregates in still water, and the erosion resistance have significantly enhanced effects; (3) With the increasing of curing age and curing agent content, the unconfined compressive strength of solidified soil samples showed a trend of gradual increase. The unconfined compressive strength can be increased by adding lime and cement properly. Adding soil curing agent PAAH can significantly improve the water and pressure resistance of soil samples, and has broad application prospects in the field of subgrade construction. [ABSTRACT FROM AUTHOR]

Rear-earth doped advanced thermal barrier coatings (TBCs) have been developed by in-situ doping of Gd into YSZ matrix by atmospheric plasma spray coating of YSZ and Gd 2 O 3 (6 to 15 mol %) premixed powders. These modified TBCs are deposited over CoNiCrAlY bond coated Inconel 718 substrate. Diffusion of Gd or Gd3+ into YSZ matrix resulted in further stabilization of its tetragonal phase which is confirmed by detailed X-Ray diffraction analysis. Microstructure and chemical compositions of doped TBCs are examined by scanning electron microscopy and energy dispersive spectroscopy, respectively. Incorporation of Gd 2 O 3 resulted in relatively denser and smoother coating compared to pure YSZ coating for identical process parameters due to finer particle size and complete melting of Gd 2 O 3 powders. However, in-situ doped coatings are sinter resistant at elevated temperature unlike pure YSZ coating which aids in retention of porosities during high temperature exposure and provide better thermal performances. Modified TBCs showed higher hardness and Young's modulus, as revealed by micro and nano hardness measurements. High temperature isothermal oxidation studies carried out between 1173 K and 1273 K allowed evaluation of the efficacy of modified TBCs for oxidation resistance and related kinetics. The results show that modified TBCs provide better oxidation resistance compared to pure YSZ coating. Erosion tests of TBCs both at ambient and elevated temperature (773 K) showed that modified coatings are more resistant to erosion compared to YSZ coating. [ABSTRACT FROM AUTHOR]

Since Chernozems are among the most fertile soils in the world, the study of their degradation is of great interest. However, the microstructure and composition of the soil organic matter (SOM) in eroded Chernozems have not yet been sufficiently studied. We studied the SOM and aggregate states of eroded Chernozems using the example of two catenas with arable Haplic Chernozems in the Kursk region of Russia. In the plow horizons (the part of the soil most susceptible to water erosion), we determined the mean-weighted aggregate diameter (MWD), structure and water stability coefficients (SC and WS; dry and wet sieving, respectively), soil organic carbon (SOC) content, and SOM composition and content (qualitative and quantitative micromorphological analyses, respectively). It was shown that with an increase in the degree of erosion, the content of SOC decreased significantly, according to both chemical and micromorphological methods of evaluation. No significant relationships were found between the degree of erosion and the indicators of the structure (except for WS, which was significantly lower in non-eroded Chernozem than in slightly and moderately eroded soils). With the increasing degree of erosion, the humus state of these soils deteriorates at the microlevel, the intensity of humification decreases, the depth of the appearance of assimilated biogenic aggregates with finely dispersed calcite in the profile increases, the structure is destroyed, lumpy aggregates form, and the proportion of planar voids increases. The downslope transport of the soil solid phase under the impact of erosion is accompanied by the accumulation of the transformation products of carbohydrates in the Chernozems in the lower part of the catena. In the Chernozems located in the transit position of the slope, the composition of SOM is characterized by the predominance of lipids and nitrogen-containing compounds. Our unique results contribute to a deeper understanding of the formation of structure and water resistance in eroded soils.

Sand solidification of earth-rock dams is the key to flood discharge capacity and collapse prevention of earth-rock dams. It is urgent to find an economical, environmentally friendly, and durable sand solidification technology. However, the traditional grouting reinforcement method has some problems, such as high costs, complex operations, and environmental pollution. Enzyme-induced calcium carbonate precipitation (EICP) is an anti-seepage reinforcement technology emerging in recent years with the characteristics of economy, environmental protection, and durability. The erosion resistance and shear strength of earth-rock dams solidified by EICP need further verification. In this paper, EICP-solidified standard sand is taken as the research object, and EICP-cemented standard sand is carried out by a consolidated undrained triaxial test. A two-stage pouring method is adopted to pour samples, and the effects of dry density, cementation times, standing time, and confining pressure on the shear strength of cemented standard sand are emphatically analyzed. The relationship between cohesion, internal friction angle, and CaCO3 formation was analyzed. After the optimal curing conditions are obtained through the triaxial shear strength test, the erosion resistance model test is carried out. The effects of erosion angle, erosion flow rate, and erosion time on the erosion resistance of EICP-solidified sand were analyzed through an erosion model test. The results of triaxial tests show that the standard sand solidified by EICP exhibits strain softening, and the peak strength increases with the increase in initial dry density, cementation times, standing time, and confining pressure. When the content of CaCO3 increases from 2.84 g to 12.61 g, the cohesive force and internal friction angle change to 23.13 times and 1.18 times, and the determination coefficients reach 0.93 and 0.94, respectively. Erosion model test results indicate that the EICP-solidified sand dam has good erosion resistance. As the increase in erosion angle, erosion flow rate, and erosion time, the breach of solidified samples gradually becomes larger. Due to the deep solidification of sand by EICP, the development of breaches is relatively slow. Under different erosion conditions, the solidified samples did not collapse and the dam broke. The research results have important reference value and scientific significance for the practice of sand consolidation engineering in earth-rock dams.

Both calcium lignosulfonate and basalt fiber can be used as soil amendments. Basalt fiber can effectively improve the cohesion and shear strength of soil, while calcium lignosulfonate can effectively improve the water stability and water holding capacity of soil. In order to explore the effect of their combined use, the effects of adding calcium lignosulfonate, basalt fiber and their combined addition on the mechanical properties and erosion resistance of loess slope were studied by soil tests and artificial rainfall erosion tests. The results show that the composite use of basalt fiber and calcium lignosulfonate can significantly improve the mechanical indexes of loess, and 1.5% calcium lignosulfonate plus 0.4% basalt fiber is the optimal dosage. Under the optimal ratio condition, the cohesion and internal friction angle of the improved soil have been increased by 67.2% and 17.8% respectively, compared with that of 1.5% calcium lignosulfonate and 14.4% and 9.8% respectively, compared with that of 0.4% basalt fiber. In addition, the disintegration rate is significantly lower than that of plain soil. The permeability of the improved loess slope has been increased significantly, the permeability coefficient decreased, the rainwater infiltration slowed down, and the corrosion resistance increased significantly. Under the condition of rainfall intensity of 50 mm/h and rainfall duration of 3 h, the cumulative brush amount is 99.8% less than that of plain soil slope. [ABSTRACT FROM AUTHOR]

The paper presents an evaluation of a number of technological processes using the formation of functional coatings based on the method of electric spark alloying, developed in the twenty-year-period at All-Russian Thermal Engineering Institute (JSC VTI). [ABSTRACT FROM AUTHOR]

Basalt fiber reinforced polymer (BFRP) composite pipe is an excellent alternative to glass and carbon fiber reinforced composite pipes in industry and promising in high recycling for polymer composite used in aerospace, marine, and automotive. To enhance the solid particle erosion (SPE) properties of filament‐wound BFRP composite pipe while preserving its mechanical properties, reinforced BFRP composite pipes were prepared to employ non‐functionalized graphene nanoplatelets (GnPs) at a reinforcement concentration of 0.25 wt.% and ultrasonication mixing technique. The SPE behavior of GnPs reinforced and non‐reinforced BFRP composite pipes were characterized by axial and radial positioning of the inner and outer surfaces of the pipes. In each case, the erosion rates of these composite pipes were evaluated at five impingement angles (30°, 45°, 60°, 75°, and 90°) and an impact velocity of 34 m/s. The erosion response of both BFRP composite pipes' outer surfaces showed a semi‐ductile in the axial positioning, with a maximum erosion rate at a 60° impingement angle. However, these composite pipes' inner surfaces in the same positioning presented a maximum erosion rate at a 45° impingement angle. Besides, it is explored that the GnPs contribute to an improvement of approximately 10%–55% in erosive wear resistance of the non‐reinforced BFRP composite pipes. The damage analysis of eroded surfaces was examined through scanning electron microscopy (SEM), and the GnPs effect upon composite pipes' erosion micromechanisms was presented and discussed in detail. Highlights: GnPs increased the BFRP composite pipe's erosion resistance.Erosion rate on the inner surface increases due to particle accumulation.GnPs improved erosion behavior via solid lubrication and mechanical properties. [ABSTRACT FROM AUTHOR]

During drilling and spraying operations, the main cause of wear and even failure of spools is the impact of rock-carrying fluid on their inner wall. In order to study the erosion condition of high-speed sand-carrying liquid–solid two-phase flow on drilling spools, researchers established an erosion model by selecting a suitable erosion theory, physical model, and boundary conditions. Numerical simulation and analysis were conducted using COMSOL software to investigate the erosion effect of the spool caused by different factors, such as flow rate, particle diameter, and fluid viscosity. The research results show that the erosion rates of drilling spool calculated by Finnie model, E/CRC model, and DNV model are similar. Moreover, the erosion rate is positively correlated with inlet velocity, erosion time, particle size, and particle mass flow rate; and negatively correlated with fluid viscosity. Therefore, in actual drilling operations, it is important to ensure drilling fluid performance and rock debris mass flow rate to carry out safe drilling operations. [ABSTRACT FROM AUTHOR]

Maintaining soil functions is crucial for human well-being, but there is a lack of integration between soil, water security, ecosystem services, and climate change. To bridge this knowledge gap and address erosion-induced soil and water losses and considering intrinsic impacts of soil structure, a three-year-long study was conducted focused on three dominant soil types (Typic Hapludult, Typic Dystrudept, and Typic Usthortent) combined with different land uses (native forest, eucalyptus plantation, rotational grazing, and extensive grazing) in a critical water supply region for the São Paulo metropolitan area in Southeastern Brazil. Surface runoff, evaluated for erosion resistance, was measured using the Cornell infiltrometer, and soil electrical resistivity tomography estimated soil water content to a depth of 1.5 m for groundwater recharge analysis. Soil hydraulic properties were also measured. The results revealed that native forest soils had higher hydraulic conductivity, particularly in the surface layer, compared to eucalyptus and pastures. Native forests in Typic Hapludult showed a higher runoff rate (200 to 250 mm h−1) due to a naturally dense subsoil layer that negatively impacted water infiltration and recharge with a high erosion potential, therefore reducing the amount of water stored. Typic Usthortent maintained a higher soil water content in pastures than in other land uses and also showed a low rate of water infiltration, resulting in perched water in the surface layer. In Typic Dystrudept, the native forest presented higher hydraulic conductivity (0–5 cm: 115.9 cm h−1) than eucalyptus (0–5 cm: 36.4 cm h−1), rotational grazing (0–5 cm: 19.4 cm h−1), and extensive grazing (0–5 cm: 2.6 cm h−1), but there were no significant differences in soil water content among land uses. This work illustrates the crucial role of native forests in affecting deep water recharge, reducing the soil surface erosion, mainly in soils without naturally subsoil layer, maintaining recharge potential. For Ultisols, pastures preserved soil structure and are therefore less impacted by soil management. With these results, a contribution is made to soil and water conservation, providing support for sustainable management practices in erosion-prone areas. [ABSTRACT FROM AUTHOR]

Sandy loess is a kind of loess with a loose structure and, high sand content, and has negative effects on the overall stability of soil. To improve the stability of sand-sandy loess, this study proposed a chemically solidified sand-sandy loess by mixing two kinds of cellulose curing agents. Through direct shear test and triaxial compression test of sand-tests on the sandy loess soil before and after curing, the shear strength of sand-loess before and after curing was analysed, and the effects of the curing form and the ratio of mixed curing agents on the physical and mechanical properties of sandloess soil were discussed. Next, the erosion resistance simulation test on solidified sand loess soil was carried out by using an indoor model test, and the simulation results were compared with the test results. On this basis, the main factors affecting the performance of solidified sand loess were analysed. Results show that, the curing effect of mixed curing agents is obviously superior to that of a single curing agent, and the shear strength of sandy loess increases with the concentration of the curing agent. With the increase of the curing soil's liquid-solid ratio of curing soil, the erosion quantity decreases gradually and reaches the minimum when the liquid-solid ratio is 1:2 and the slope is 30°, showing the best erosion resistance. The obtained conclusions provide some references to in determining the slope curing mode of sandy loess in practical engineering. [ABSTRACT FROM AUTHOR]

3D sand printing, a binder jetting-based additive manufacturing process, can directly produce sand molds with complex geometries for high-quality and lightweight metal parts. However, there is still a lack of information on how to degrade and erode the mechanical integrity of 3D sand molds. Here, correlations have been investigated between 3D printing materials and various properties of 3D-printed molds: microstructure, flexural strength, reliability, and erosion resistance. As a result, given the mechanical strength and the formation of the binder necks, the most appropriate flexural strength of 4.2 MPa, reliability of 7.8, and high erosion resistance of 86% are achieved from the 3D-printed sand molds prepared with a binder of 2 wt% and an activator of 0.25 wt%. The exhaust manifold casted using a 3D-printed sand mold with optimum conditions, it shows the same or better performance than the genuine part.

Erosion seriously threatens the safety of high-speed rotating mechanical components in very harsh service environments, particularly for lightweight titanium alloy matrix material. In order to improve the erosion resistance of titanium alloy, TiAlSiN coatings with different phase compositions are deposited on TC6 titanium alloy using a high-power pulse magnetron sputtering discharge (HPPMS) system under various discharge voltages. The componential and microstructural evolution as well as mechanical properties of the TiAlSiN coatings are evaluated by X-ray diffraction, scanning electron microscopy, and nanoindentation, respectively. The erosion performance relative to titanium alloy is investigated by a sand blasting tester. With the increase in discharge voltage from −500 to −600 V, the peak of discharge current increases from 105 to 225 A. The prepared TiAlSiN coatings show a shift of the preferred crystallographic orientation from (220) to (200), but all of them have a dense nanocomposite structure. Their hardness (H) and elastic modulus (E) gradually increase before decreasing, arriving at maximum values of 35.34 and 360.5 GPa at −570 V. The erosion resistance of the TiAlSiN coatings dependent on the discharge voltage is consistent with the H/E ratio change. The TiAlSiN coatings prepared at −560 V exhibit the optimal erosion resistance, which is 15 times that of the TC6 substrate. The erosion behavior of the coatings is positively correlated with their hardness and toughness. Adjusting the discharge voltage of the HPPMS pulse is finally proved to be an effective way of tailoring the coating phase compositions to improve the erosion resistance of titanium alloy. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures in the marine environment face serious corrosion risks. Coating protection and adding corrosion inhibitors are the most economical and effective methods. In this study, a nano-composite anti-corrosion filler with a mass ratio of CeO2:GO = 4:1 was prepared by hydrothermally growing cerium oxide on the surface of graphene oxide. The filler was mixed with pure epoxy resin at a mass fraction of 0.5% to prepare a nano-composite epoxy coating. The basic properties of the prepared coating were evaluated from the aspects of surface hardness, adhesion grade, and anti-corrosion performance on Q235 low carbon steel subjected to simulated seawater and simulated concrete pore solutions. Results showed that after 90 days of service, the corrosion current density of the nanocomposite coating mixed with corrosion inhibitor was the lowest (Icorr = 1.001 × 10−9 A/cm2), and the protection efficiency was up to 99.92%. This study provides a theoretical foundation for solving the corrosion problem of Q235 low carbon steel in the marine environment. [ABSTRACT FROM AUTHOR]

This article presents an analysis of the effect of high velocity plasma spraying (HV-APS) parameters of WC-CrC-Ni powder. Plasma spraying processes were carried out using a three-electrode Axial III type torch with central powder injection, in which a supersonic nozzle with a diameter of 5/16 inch was installed. The following were taken as variable parameters: power current per electrode (140, 160, 180A), hydrogen flow rate (10, 20, 30 NLPM) and powder feed rate (15, 20, 25 g/min). The obtained coatings were characterized by thicknesses exceeding 200 μm and their porosity was very low (<1%), similar to those obtained by the HVOF method most commonly used for spraying carbide coatings. The obtained coatings were characterized by hardness in the range of 800–950 HV0.5 - depending on spraying parameters. The solid particle erosion test showed that the WC-CrC-Ni coating - regardless of the spraying parameters - has good erosion resistance. The analysis of the obtained test results indicates that the use of the HV-APS process allows producing carbide coatings with properties similar to those obtained in the HVOF spraying method and significantly better compared to conventional plasma spraying (APS). [ABSTRACT FROM AUTHOR]