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A finite model incorporating microstructure was developed to investigate the thermal shock resistance of TiB2‒B4C composite ceramic cutting tool materials. Numerical simulations were conducted to analyze changes in the transient temperature field and thermal stress field during the thermal shock process. TiB2‒B4C composite ceramic tool materials were fabricated using discharge plasma sintering technology. With different B4C contents, different sintering temperatures and holding times as study variables, optimization of the sintering process parameters and ceramic material components was achieved through testing the mechanical and microscopic morphology of the ceramics. Thermal shock water quenching experiments were performed, and the strength‐decay method was employed to assess the thermal shock resistance of TiB2‒B4C ceramics. The findings indicate that the optimal sintering conditions are temperature of 1700°C and holding time of 5 min. The TiB2‒B4C ceramic material containing 20 vol% B4C exhibits superior comprehensive mechanical properties and thermal shock resistance, and its relative density, fracture toughness, hardness, and flexural strength were 99.3%, 6.8 MPa m1/2, 22.8 GPa, and 598 MPa, respectively. The critical thermal shock temperature difference falls within the range of 400°C‒500°C. [ABSTRACT FROM AUTHOR]

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

The research on and application of electric fields to promote the rapid infiltration of ions into cement concrete have been widely explored. Still, there are few studies on the migration of sulfate ions using electric fields. In this paper, a new test method is designed using the principle of electric fields, that is, to accelerate the attack of sulfate into concrete under the action of the electric field, to test the resistance of concrete to sulfate attack. By testing different water–cement ratios, different pulse frequencies, different ages, and different soaking environments, the influence of the electric field on the sulfate resistance of concrete was analyzed. The results show that the compressive strength of concrete in a sulfate attack environment is smaller than that of conventional attack and water immersion environment when the water–cement ratio is 0.3, 0.4, and 0.5 under the action of the electric field and increases with the increase of water in the water–cement ratio. Compared with a 14 day test, the compressive strength of concrete in a sulfate attack environment decreased by 1.9%, 8.6%, and 2.9%, respectively, at 28 days, which was faster than that of conventional attack and water immersion. The compressive strength of the concrete in the sulfate attack environment during the full immersion test and the semi-immersion test is smaller than that of the conventional attack and water immersion, and the semi-immersion test method is more obvious than the full immersion test method. The microscopic morphology of the test group, the water group, and the solution group were compared. From the microscopic morphology comparison, it can be seen that the electric field accelerates the diffusion of sulfate ions into the cement concrete and accelerates the reaction of sulfate ions with the relevant components in the cement concrete. Given the demand for concrete to resist sulfate attack under the action of the electric field, developing new and efficient protective materials is an important research direction. At present, the market lacks protective materials specifically for such an attack environment. This paper provides the theoretical basis and technical support for improving the effectiveness of concrete surface protection technology and engineering practices. [ABSTRACT FROM AUTHOR]

Determining the shear‐velocity dependence of dry granular friction can provide insight into the controlling variables in a dry granular friction law. Some laboratories believe that the quality of this study is at the forefront of the discipline for the following reasons. Results suggest that granular friction is greatly affected by shear‐velocity (v), but shear experiments over the large range of naturally occurring shear‐velocities are lacking. Herein we examined the shear velocity dependence of dry friction for three granular materials, quartz sand, glass beads and fluorspar, across nine orders of magnitude of shear velocity (10−8–2 m/s). Within this range, granular friction exhibited four regimes, following a broad approximate "m" shape including two velocity‐strengthening and two velocity‐weakening regimes. We discuss the possible physical mechanisms of each regime. This shear velocity dependence appeared to be universal for all particle types, shapes, sizes, and for all normal stresses over the tested range. We also found that ultra‐high frequency vibration as grain surfaces were scoured by micro‐chips were formed by spalling at high shear velocities, creating ∼20 μm diameter impact pits on particle surfaces. This study provides laboratory laws of a friction‐velocity (μ‐v) model for granular materials. Plain Language Summary: Numerous phenomena of earth science can be simplified to shearing granular systems, such as landslide gouge and rock avalanches. It is believed that friction varies with shear velocity, and this is no exception for dry granular materials. Studying the law of friction variation over as large a range of velocity changes as possible aids in establishing a full life‐cycle hypothesis for landslides from initiation, through movement to cessation. We sheared granular materials across nine orders of magnitude, from 10−8 to 2 m/s and obtained an "M" shape law for the variation of friction with velocity. By analyzing the acoustic frequency of shear experiments at different velocities, we discovered that the acoustic frequency increased with shear velocity. By comparing the microscopic morphology of the particle surface before and after high‐velocity shearing, we hypothesized that the impact pits may be left by particle collisions during high‐velocity shearing. We proposed that the role of ultra‐high frequency vibration on high‐velocity shear weakening should be considered, which provides a basis for accurately revealing the physical mechanism of granular friction variation with velocity. Key Points: This paper examines the shear velocity dependence of friction for dry granular materials, across nine orders of magnitude in shear velocity (10−8–2 m/s)An "M‐shaped" law for the variation of friction with velocity is obtained including two velocity‐strengthening and two velocity‐weakening lawsThere is microscopic evidence that ultra‐high frequency vibration may cause high velocity shear weakening [ABSTRACT FROM AUTHOR]

The microstructure, reaction mechanism and mechanical properties of (MgCoNiCuZn)O high-entropy ceramics prepared by microwave sintering technology were studied. Single-phase (MgCoNiCuZn)O high-entropy ceramics can be prepared in about 1 h when the preforming pressure is 5 MPa and the temperature is higher than 900 °C. By analyzing the microscopic morphology and density, it can be known that the density gradually increases with the increase of temperature. When the temperature is higher than 1000 °C, the pores in the sample indicate the packing, agglomeration and segregation of Cu2+ atoms at the grain boundaries. When the mass of the raw material is 20 g, it exhibits a good impedance matching effect during microwave heating. The sintered (MgCoNiCuZn)O ceramic with a density of 92.87 %, a flexural strength of 290 ± 20 MPa, an elastic modulus of 187.05 ± 5 GPa, and a microhardness of about 7 GPa. [ABSTRACT FROM AUTHOR]

The effect of process parameters on geometric dimensions is complex during belt-heated incremental sheet forming, leading to control difficulties in the geometric dimension of parts. In this study, the geometric errors were analyzed under the action of different process parameters, and the corresponding influence law was obtained through macro- and microexperiments. On this basis, the micromorphology of the deformation region section was analyzed in detail, and the effect of process parameters on micromorphology characteristics was obtained during belt-heated incremental sheet forming. Meanwhile, the dislocation density of the deformation region section was analyzed through XRD, and the change law of the dislocation density was revealed under the action of different process parameters. Therefore, the macro and micro effect mechanism of process parameters on geometric dimensions was verified, and then the control method of the geometric dimension was obtained in belt-heated incremental sheet forming. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study employed macroscopic uniaxial compression tests at low and medium strain rates, coupled with microscopic electron microscopy, to extensively analyse the impact of thermomechanical coupled aging on the accelerated aging of Hydroxyl‐terminated Polybutadiene (HTPB) propellants, contrasting it with the effects of isolated factors such as heat and dynamic reciprocating force. Results indicate that at various environmental temperatures (323 K, 343 K, and 363 K), thermomechanical coupled aging more significantly affects HTPB propellants than isolated factors. This effect is macroscopically evident in increased ease of deformation, permanent deformation during aging, continual increase in dissipated energy, and a decrease in average stress and ultimate strain post‐aging. Microscopically, the effect predominantly arises from the interplay between matrix thermal degradation and particle fragmentation, which rapidly accumulate and substantially impact the material's macroscopic mechanical properties. Furthermore, as the aging temperature rises, the alterations in both macroscopic mechanical properties and microscopic morphology of HTPB propellants become more pronounced. However, overly high temperatures may swiftly result in substantial material performance deterioration. Consequently, while elevating temperature effectively accelerates thermomechanical aging, the potential adverse effects on material performance must be judiciously considered. This underscores the necessity of balancing temperature regulation with aging efficiency enhancement in HTPB propellants to ensure effective control and quantitative assessment of the aging process, while minimizing material degradation. [ABSTRACT FROM AUTHOR]

BACKGROUND: The lower cervical vertebral pedicle is the main stress site of the posterior column of the spine, which is of great significance for the maintenance of the stability of the human center of gravity and the reduction of shock. At present, there are few reports on the characteristics of the internal bone trabeculae, and the characteristics of the joint site of the vertebral pedicle with the articular process and the vertebral body. It is urgent to understand the fine anatomical structure of the vertebral pedicle and the relationship and function of each part. OBJECTIVE: To observe the microanatomical morphology of the vertebral pedicle by Micro-CT scanning of cervical vertebra specimens, and to measure and analyze the microstructure and morphometric parameters of the bone trabecula in the cervical pedicle under normal conditions to evaluate the safety performance of the cervical spine. METHODS: Micro-CT scanning was performed on 31 sets of cervical vertebrae C3-C7. By checking and reconstructing the areas of interest in the bone trabecular within the vertebral pedicle, the morphological characteristics and distribution direction of the bone trabecular within the cervical pedicle were observed, and the bone microstructure parameters were detected, and the differences in the bone microstructure of the C3-C7 vertebral pedicle were analyzed and compared. RESULTS AND CONCLUSION: (1) The Micro-CT images showed that the honeycomb bone trabeculae of the pedicle of the lower cervical spine presented a complex network of microstructures. The trabeculae near the cortical bone were lamellar and relatively compact, extending forward toward the vertebral body and backward toward the articular process lamina. Abatoid bone trabeculae extended into the medullary cavity and transformed into a network structure, and then into rod-shaped bone trabeculae. The rod-shaped bone trabeculae were sparsely distributed in the medullary cavity. (2) Statistical results of morphological parameters of bone trabeculae showed that bone volume fraction values in C4 and C5 were higher than that in C7 (P < 0.05). The bone surface/ bone volume value in C7 was higher than that in C3, C4 and C6 (P < 0.05). The bone surface density of bone trabeculae in C7 was higher than that in C3, C4, C5 and C6 (P < 0.05). Trabecular thickness in C7 was higher than that in C3, C4 and C5 (P < 0.05). Bone surface/bone volume and bone surface density of the left pedicle bone trabecular were greater than those on the right side (P < 0.05). (3) The microstructural changes of C3-C7 were summarized, in which the load capacity and stress of the C7 pedicle were poor, and the risk of injury was high in this area. [ABSTRACT FROM AUTHOR]

This study investigated the effects of various load conditions on the wear characteristics of Si3N4 full-ceramic ball bearings in response to 6007 Si3N4 full-ceramic ball bearing operation-related wear problems. Using an ABLT-1A tester, the wear behavior of 6007 Si3N4 ceramic ball bearings was investigated under loads of 100, 500, and 800 N, with a rotation speed of 6000 r/min and a duration of 12,000 min. The test load, and the 100 and 500 N radial loads had an equilibrium temperature difference of about 1.91°C, while the 500 and 800 N radial loads exhibited an equilibrium temperature difference of about 2.35°C. Each group's temperature rate difference is evident. Bearing internal clearance increased by 35.7%, 50.34%, and 56.1%, respectively, and the fault frequencies of the bearing elements appeared within the vibration signal. The surface roughness of each component of the bearing increased with the increase in the test load, while a large number of plow grooves and spalling appeared on the surface, and severe cage wear was observed. Results show that when load, temperature, clearance, runout, and frequency domain amplitude increased, the following were observed: development of rolling body surface spalling and a large area of wear spot; raceway surface crater along the direction of movement of the fur-row; obvious scratches were observed on the cage surface in the pocket hole edge melting phenomenon; the cage became the bearing system's "weak link." The test results are a reference value for the wear behavior of Si3N4 full-ceramic ball bearings under this test load. [ABSTRACT FROM AUTHOR]

To promote the resource utilization of steel slag and improve the production process of steel slag in steelmaking plants, this research studied the characteristics of three different processed steel slags from four steelmaking plants. The physical and mechanical characteristics and volume stability of steel slags were analyzed through density, water absorption, and expansion tests. The main mineral phases, morphological characteristics, and thermal stability of the original steel slag and the steel slag after the expansion test are analyzed with X-ray diffractometer (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TG) tests. The results show that the composition of steel slag produced by different processes is similar. The main active substances of other processed steel slags are dicalcium silicate (C2S), tricalcium silicate (C3S), CaO, and MgO. After the expansion test, the main chemical products of steel slag are CaCO3, MgCO3, and calcium silicate hydrate (C-S-H). Noticeable mineral crystals appeared on the surface of the steel slag after the expansion test, presenting tetrahedral or cigar-like protrusions. The drum slag had the highest density and water stability. The drum slag had the lowest porosity and the densest microstructure surface, compared with steel slags that other methods produce. The thermal stability of steel slag treated by the hot splashing method was relatively higher than that of steel slag treated by the other two methods. [ABSTRACT FROM AUTHOR]

To investigate the effect of ZrC on the ablative properties of C/SiC composites in a high-temperature environment, the oxidative ablation of C/SiC and C/SiC-ZrC composites at high-temperatures was examined through ablation tests. In this study, two ceramic matrix composites, C/SiC and C/SiC-ZrC, were prepared by chemical vapor deposition and precursor impregnation pyrolysis. The ablation properties of the materials were tested and analyzed using an oxyacetylene flame to simulate a high-temperature environment. The results revealed that the line ablation rate of C/SiC-ZrC was 8.48% and 20.81% lower than that of C/SiC at 30 s and 60 s, respectively. At the same ablation time, the depth of the crater resulting from erosion of the C/SiC material by the high-temperature airflow was deeper than that of C/SiC-ZrC. The traces of the fibers subjected to erosion were more prominent. In a longitudinal comparison, the mass ablation rate of C/SiC-ZrC material decreased with the increase in time, while the line ablation rate initially increased rapidly and then decreased. From 30 s to 90 s of ablation, the line ablation rate and mass ablation rate decreased by 55.62% and 89.5%, respectively. The overall trend for both rates was a decrease with the increase in time. Under the same ablation time, the ablation rate of C/SiC-ZrC was generally lower than that of C/SiC. This is because the generated molten ZrO2 was more viscous and denser than SiO2, effectively blocking oxidizing gases from penetrating the interior of the material. The molten ZrO2 provided better protection for the substrate in the high-temperature environment. [ABSTRACT FROM AUTHOR]

The inverse relationship between the setting time and high early strength of magnesium potassium phosphate cement (MKPC) affects its practical application in low-temperature environments. However, there has been limited research on adjusting the type and proportion of retarders to achieve a dynamic balance. In this study, we investigated the impact of a composite retarding agent (sucrose, replacing a portion of borax) on the setting time, fluidity, dry shrinkage rate, and mechanical properties of MKPC at different temperatures (20 ± 2 °C, 0 ± 2 °C, and −10 ± 2 °C). The relevant indexes were analyzed and the optimum sucrose dosing range was formulated. Using scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests to observe the hydration products and microscopic morphology of MKPC with varying sucrose dosages at low temperatures. The physical phases were quantitatively analyzed using the Rietveld method. Finding demonstrated that at room temperature, the setting time of MKPC doped with 2.5% and 5% sucrose was extended by 5.58 and 16.72 min, respectively, and its stability improved by 19.9% and 24.1% compared to normal MKPC at − 10 ± 2 °C. Moreover, the stability of MKPC doped with 2.5% and 5% sucrose at − 10 ± 2 °C improved by 19.9% and 24.1%, respectively, compared to normal MKPC. Furthermore, the MKPC slurry with a sucrose /dead-burned magnesia (S/M) of 2.5% had good dry shrinkage properties, and better long-term strength at low temperatures than conventional MKPC. When the temperature of the specimen was maintained at − 10 ± 2 °C and then raised to room temperature, its strength reached 89.6% at 20 ± 2 °C, which was more suitable for the emergency repair and rehabilitation of buildings located in cold regions. However, a higher S/M may inhibit the development of the solid phase in MKPC, resulting in a significant decrease in all aspects of its performance.

To perform an in-depth study of the crystal growth habits and phase changes of alumina and its precursors in reaction systems, this paper studied the effects of reactant type and addition order on the morphology of alumina using hydrothermal methods with different precipitants and aluminum sources as reactants. Research has shown that sodium bicarbonate and ammonium bicarbonate can be used as precipitants to prepare adhered spherical alumina and irregular short rod alumina, while potassium bicarbonate can be used as a precipitant to prepare hexagonal flake alumina. Using aluminum sulfate octahydrate, aluminum chloride hexahydrate, and aluminum nitrate, nine hydrates were prepared as aluminum sources, and agglomerated alumina, irregular short rod-shaped alumina, and fused alumina were obtained. The order of reactant addition affects the precursor phase of alumina, thereby affecting the microstructure of alumina after calcination, resulting in flake alumina with pores and short rod alumina. The results of this paper will provide theoretical guidance for the preparation of alumina with different micromorphologies. [ABSTRACT FROM AUTHOR]

This study examines a versatile polymer known as polysurfactant, which is synthesized by co-polymerizing flexible acrylamide and sodium acrylate hydrocarbon chain. The polymer serves as a backbone and possesses active functional groups. Notably, the polysurfactant exhibits superior plugging and flooding abilities compared to conventional polymers. The primary objective of this paper is to investigate the properties and oil displacement characteristics of the polysurfactant through indoor physical simulation experiments. The results demonstrate that the multi-branched structure of the polysurfactant enhances its ability to associate, leading to the formation of a unique spatial network structure. The inclusion of multi-branched structures notably amplifies the association effect. The critical concentration for the association is estimated to be around 800 mg/L, at which juncture the polysurfactant exhibits a viscosity retention rate surpassing 90% subsequent to shearing. Furthermore, this spatial network structure exhibits self-recovery capabilities after experiencing shear failure and displaying strong viscosity and shear resistance. In addition, the concentration of the polysurfactant can control the hydrodynamic feature size, which shows its adaptability in regulation and oil-repelling functions at reservoir permeabilities ranging from 500 to 2000 × 10−3 μm2 with resistance coefficients ranging from 108 to 320. During the microscopic oil displacement process, the polysurfactant exerts a significant impact on mobility control, while the elastic pull clearly demonstrates a commendable viscoelastic oil displacement effect. The polysurfactant exhibits a specific degree of emulsification capability towards crude oil, leading to the emulsion exhibiting typical pseudoplastic fluid characteristics. The utilization of emulsification transportation and emulsification blockage contributes to the enhancement of oil recovery. As a result, the polysurfactant exhibits multifaceted capabilities, encompassing profile control, flooding, and plugging, owing to its unique structural characteristics. Through the implementation of a field test focused on flooding in the Daqing Oilfield, a significant enhancement in the recovery rate of 10.85% is observed, accompanied by a favorable input–output ratio of 1:3.86, thereby generating significant economic advantages. [ABSTRACT FROM AUTHOR]

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

Vehicle fuel leaks can adversely affect the performance of asphalt pavements. To study the mechanisms of fuel corrosion damage in asphalt, four asphalt binders were selected in this study, and the evolution of their rheological and microscopic properties was investigated. Fuel corrosion caused continuous mass loss in asphalt binders. Base asphalt lost more than 50% of its mass after 24 h of fuel corrosion, while modified asphalts had better resistance. According to dynamic shear rheometer tests and multiple stress creep recovery tests, modifiers improved the high-temperature rheological properties of these asphalt binders. As the degree of fuel corrosion deepened, the indexes characterizing the high-temperature performance deteriorated. Rubber-modified asphalt showed the best resistance to high-temperature deformation, while the performance of LDPE-modified asphalt was more stable. In contrast, fuel corrosion improved the resistance of asphalt binders to low-temperature cracking to some extent: the creep strength (S) decreased as the creep rate (m) increased, and the resistance of SBS-modified asphalt to low-temperature cracking was optimal, with a 36% decrease in S-value after 24 h of fuel corrosion. Fourier transform infrared spectroscopy tests showed that diesel corrosion was a process of this physical dissolution, with no change in the chemical functional groups. Meanwhile, by using fluorescence images and analyzing the four-component test results, we found that fuel corrosion disrupted the stabilized structure formed by the modifiers, and the heavy components in the asphalt binders were converted into light components. This study reveals the evolution of the rheological and microscopic properties of asphalt under fuel corrosion, which can provide a reference for the optimization of fuel corrosion resistance in asphalt pavement. [ABSTRACT FROM AUTHOR]

This paper addresses a range of environmental issues stemming from the improper disposal of construction waste and its low recycling rate by examining the effects and mechanisms of polyvinyl alcohol (PVA) solution in modifying recycled aggregates. Basic physical properties, energy-dispersive spectroscopy (EDS), X-Ray diffraction (XRD), and scanning electron microscopy (SEM) were employed to study these effects and mechanisms. Tests on basic mechanical properties were performed to assess the impact of aggregate modification and the brick-concrete ratio on recycled brick-aggregate concrete's mechanical characteristics. Nuclear magnetic resonance and microhardness tests were performed to analyze the influence exerted by PVA modification on the interfacial transition zone (ITZ), microstructure, and pore structure, thus exploring the connection between modified recycled-brick-aggregate concrete's microstructure and its icromechanical properties. The findings show that the water absorption and crushing index of recycled aggregates (RA) immersed in a 10% PVA solution for 24 h decrease significantly, while the apparent density increases most notably. This phenomenon can be ascribed to the development of a PVA coating on the exterior of the reused aggregates. The optimal mechanical properties for recycled brick aggregate concrete (RAC) occur when the replacement rate is 30% and the brick-concrete ratio is 1:1. The compressive strength is 44.2 MPa, the bending strength is 15.6 MPa, and the splitting tensile strength is 3.85 MPa. Additionally, the modification with PVA results in a higher percentage of transition pores, while simultaneously reducing the percentage of macropores. There is an uptick in the frequency of harmless and less harmful pores, and a declining proportion of harmful and more harmful pores. The ITZ's structural morphology in the RAC is effectively improved by the coating structure formed through the bonding of the polymer with cement hydration products, and PVA modification reduces the thickness of this zone. [ABSTRACT FROM AUTHOR]

Designing a stable, low-cost, and efficient electrocatalyst is the key to promoting electrolytic hydrogen production. Herein, a porous Ni 3 Si electrode with excellent HER activity prepared by elemental powder reaction synthesis and chemical etching is reported. The microstructure analysis results show that the porous Ni–Si material prepared with an atomic ratio of 3:1 is composed of a single Ni 3 Si phase. After etching treatment, the pore structure of the porous Ni 3 Si electrode increased significantly, and its specific surface area increased by nearly 40 times. According to the findings of the hydrogen evolution tests, the etched Ni 3 Si electrode performs better than the Ni 3 Si electrode in terms of hydrogen evolution, and at a current density of 10 mA cm−2, its overpotential is −116 mV. Meanwhile, the Ni 3 Si electrode exhibits good HER stability over 24 h and maintains this HER activation beyond 1000 cycles. The hydrogen free-energy of adsorption is calculated by means of density functional theory. It was shown from the analysis that the optimal active site for H∗ adsorption is on the Ni atom and that ΔG H∗ is 0.086 eV, demonstrating the business feasibility of aqueous electrolytic hydrogen creation at a porous Ni 3 Si electrode. • The porous Ni 3 Si electrodes were prepared by elemental powder reaction synthesis. • Chemical etching of the electrodes can significantly increase their BET and ECSA. • The electrodes exhibited good HER activity and stability over a period of time. • DFT calculations showed the best active site for H∗ adsorption is on the Ni atom. [ABSTRACT FROM AUTHOR]

To develop an eco-friendly artificial turf filling for replacing rubber elastomer particles, seven kinds of natural materials (cork, soft oak, champagne bark, oak bark, pine bark, willow bark, and vermiculite) were selected and processed into particles with a dimension of 1–2 mm. The water absorption performance, mold resistance, resilience, compression characteristics, and the repose angle were tested, and the surface microscopic morphology of granular materials was observed. The experimental results showed that the champagne bark had the largest plastic deformation range under pressure load, which was 0.21–7.82 KN. And the champagne bark particles had the best resilience, which was respectively 8.9 % and 7.1 % before and after compression, and its angle of repose was 36.8°, which was 9 % higher than that of the thermoplastic elastomer (TPE) particle. Additionally, champagne bark had better mold resistance compared with the other six natural materials, and its mold only occurred in the mold inoculation center. In conclusion, champagne bark could be considered as an artificial turf filling granule to replace TPE rubber. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The physical and mechanical properties of rocks change significantly after being subjected to high temperatures, which poses safety hazards to underground projects such as coal underground gasification. In order to investigate the effect of temperature on the macroscopic and microscopic properties of rocks, this paper has taken sandstone as the research object and conducted uniaxial compression tests on sandstone specimens at different temperatures (20–1000 °C) and different heating rates (5–30 °C/min). At the same time, the acoustic emission (AE) test system was used to observe the acoustic emission characteristics of the rock damage process, and the microstructural changes after high temperature were analyzed with the help of a scanning electron microscope (SEM). The test results show that the effect of temperature on sandstone is mainly divided into three stages: Stage I (20–500 °C) is the strengthening zone, the evaporation of water and the contraction of primary fissures, and sandstone densification is enhanced. In particular, the compressive strength and elastic modulus increase, the macroscopic damage mode is dominated by shear damage, and the fracture micromorphology is mainly brittle fracture. Stage II (500–600 °C) is the transition zone, 500 °C is the threshold temperature for the compressive strength and modulus of elasticity, and the damage mode changes from shear to cleavage damage, and the sandstone undergoes brittle–ductile transition in this temperature interval. Stage III is the physicochemical deterioration stage. The changes in the physical and chemical properties make the sandstone compressive strength and modulus of elasticity continue to decline, the macroscopic damage mode is mainly dominated by cleavage damage, and the fracture microscopic morphology is of a more toughness fracture. The effect of different heating rates on the mechanical properties of sandstone was further studied, and it was found that the mechanical properties of the rock further deteriorated under higher heating rates. [ABSTRACT FROM AUTHOR]

In order to improve the service quality of roads and resolve the problem of defects in the conventional asphalt pavement in service, this paper uses a 5.3% aluminate coupling agent to modify the surface of nano-ZnO and prepares a composite-modified asphalt with nano-ZnO and basalt fiber (BF) as modifiers. First, the basic performance of different types of asphalt was investigated by means of a rotary film oven experiment. Then, a dynamic shear rheology experiment was carried out to analyze the high-temperature anti-rutting performance of the composite-modified asphalt at different temperatures and frequencies. Then, using a bending creep stiffness test, the low-temperature properties of the composite-modified asphalt were investigated. Finally, the microstructure and modification mechanisms of the composite-modified asphalt were analyzed with scanning electron microscopy and infrared spectroscopy. The results indicate that the anti-aging performance of the nano-ZnO/BF composite-modified asphalt is significantly improved after adding fibers to the modified asphalt. The average mass loss ratio is only 0.192%. At 46 °C, the rutting coefficient of the composite-modified asphalt was increased by 62.3%. The frequency master curve is always at the highest position and continues to rise, indicating a significant improvement in the high-temperature anti-rutting performance of the composite-modified asphalt. At 24 °C, the creep stiffness modulus S value of the composite-modified asphalt increased by 24.9%; moreover, there is no obvious effect of improving low temperature, but the variation range of creep tangent slope m of the modified asphalt after aging is decreased, which further shows that the addition of a modifier can decrease the influence of aging on asphalt. Nanoparticles are uniformly dispersed in the asphalt and form a three-dimensional interconnected structure with BF, which effectively improves the overall performance of the asphalt. Nano-ZnO and fibers have weak chemical reactions in matrix asphalt, but they are physically dispersed and compatible. [ABSTRACT FROM AUTHOR]

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

In order to advance the utilization rate of multi-source solid wastes in the Ningxia region of China, 16 groups of pavement base mixtures were designed with cement and fly ash (FA) as binders, steel slag (SS), silicon manganese slag (SMS), and recycled crushed stone (RCS) as composite aggregates. The evolution laws of mechanical and frost resistance properties of the mixture were investigated by unconfined compressive strength (UCS), indirect tensile strength (ITS), freeze–thaw (FT), and ultrasonic detection tests. Then, the strength formation mechanisms were revealed by microscopic characterization technology. The mathematical models between UCS-ITS, UCS-ultrasonic amplitude, FT cycles-UCS damage, and frost resistance coefficient-relative dynamic elastic modulus Er were established. The results show that cement content and curing age exhibited a positive effect on the mechanical strength and frost resistance of the mixture. When the replacement rate of SS was 60%, the mechanical strength and frost resistance were preferable. The R2 of the strength relationship models constructed was greater than 0.9, indicating high fitting accuracy. With the extension of the curing age, the cementitious products such as C-S-H (hydrated calcium silicate) and AFt (ettringite) developed entirely, and they were interlocked and cemented with each other, resulting in the micro-morphology developed from the three-dimensional network structure to the dense system. The macroscopic behavior incarnated that the mechanical strength and frost resistance of the mixture were significantly enhanced. [ABSTRACT FROM AUTHOR]

This research investigated the bond properties at high temperatures and with hybrid fiber addition between basalt fiber reinforced polymer (BFRP) bars and hybrid fiber-reinforced concrete (HFRC). The tensile strength and appearance morphology of BFRP bars were analyzed. Used scanning electron microscopy (SEM) to examine the microscopic morphology and used the bond-slip constitutive model to fit the bond-slip curves. When BFRP bars after exposed to 300 °C, their tensile strength dropped by 42%. With the increasing temperature, the bond strength and stiffness of normal concrete (NC) specimens decreased by 27.3 % and 67.5 %, respectively, while HFRC specimens decreased by 20.8 % and 55 %, respectively. Hybrid fibers increased the bond strength and stiffness of HFRC specimens by 27.1 % and 49.1 %, respectively. The best fitting models were the Malvar model and the Continuous Curve model.

To study the effect of dry ice on the performance of alkali-activated binders, we added dry ice to an alkali-activated slag (AAS). The addition amount was set to 5%, 10%, and 15% of the slag mass, depending on the amount of CO2 emitted by the material used in the preparation process. Microscopic experiments were performed to analyze the effect of dry ice on the hydration products of the AAS paste; transmission electron microscopy and scanning electron microscopy were used to observe the morphology of the hydration products. Furthermore, experimental tests for the compressive strength, ultrasonic pulse velocity, and electrical resistivity were performed. The results showed that compared with the content of the overall reaction products, the effect of dry ice on the reaction rate was more evident. The addition of dry ice slowed the hydration of the AAS, and the production of the hydration products, such as calcium aluminum silicate hydrate (C-A-S-H) gels, was significantly reduced in the early stage (1 d). Experiments on the strength showed that adding more than 5% dry ice degraded the early mechanical properties of the AAS. However, the mechanical properties of the AAS with dry ice added in the middle (3 and 7 d) and late (28 d) stages rapidly improved because the dry ice was added to the AAS to form potassium and calcium carbonate. In the middle (3 and 7 d) and late (28 d) stages, CO32− underwent a carbonation reaction to form carbonate compounds, enhancing the mechanical properties of the AAS.

Aluminum (Al) particles are commonly added to energetic materials including propellants, explosives and pyrotechnics to increase the overall energy density of the composite, but aluminum agglomeration on the combustion surface may lower the combustion efficiency of propellants, resulting in a loss in two-phase flow. Therefore, it is necessary to understand the agglomeration mechanism of aluminum particles on the combustion surface. In this paper, a high-pressure sealed combustion chamber is constructed, and high-speed camera is used to capture the whole process of aluminum accumulation, aggregation and agglomeration on the combustion surface, and the secondary agglomeration process near the combustion surface. The microscopic morphology and chemical composition of the condensed combustion products (CCPs) are then studied by using scanning electron microscopy coupled with energy dispersive (SEM-EDS) method. Results show that there are three main types of condensed combustion products: small smoke oxide particles oxidized by aluminum vapor, usually less than 1 μm; typical agglomerates formed by the combustion of aluminum agglomerates; carbonized agglomerates that are widely distributed, usually formed by irregular movements of aluminum agglomerates. The particle size of condensed combustion products is measured by laser particle size meter. As the pressure increases from 0.5 MPa to 1.0 MPa in nitrogen, the mass average particle size of aluminum agglomerates decreases by 49.7%. As the ambient gas is changed from 0.5 MPa nitrogen to 0.5 MPa air, the mass average particle size of aluminum agglomerates decreases by 67.3%. Results show that as the ambient pressure increases, the higher oxygen content can improve combustion efficiency and reduce the average agglomeration size of aluminum particles.

Magnetic grinding has the characteristics of conformal machining. However, when a small grinding head is used to magnetically grind a workpiece with a large twist, the difference in the gap between the grinding head at different positions of the workpiece poses a challenge to the magnetic grinding process. In order to improve the surface quality of magnetic grinding and further reduce the influence of the gap difference between the grinding head and the workpiece on the surface roughness, an elastic magnetic pole grinding head with polyurethane elastomer as the magnetic pole carrier was designed, and its magnetic field simulation analysis and verification were carried out. In the experiment, the self-made diamond magnetic abrasive was used to compare the grinding performance of the polyurethane elastic magnetic pole grinding head and the ordinary magnetic pole grinding head under different machining gaps. The influence of the process parameters such as spindle speed, feed rate and abrasive particle size on the surface roughness of the workpiece was studied experimentally. The experimental results show that under the same process parameters, the processing performance of the polyurethane elastic magnetic pole grinding head is better than that of the ordinary magnetic pole grinding head under different machining gaps. Using polyurethane elastic grinding head, when the spindle speed is 800 r/min, the machining gap is 2.0 mm, the feed speed is 5 mm/min, and the abrasive particle size is 62 to 90 μm, the magnetic grinding effect is the best. After 12 minutes of grinding, the surface roughness Ra of TC4 titanium alloy can be reduced from the initial 0.350 μm to 0.039 μm, and the surface roughness improvement rate reaches 89%. The results verify the effect of the elasticity and profiling characteristics of the polyurethane elastic layer on the quality of the machined surface.

The addition of a temperature-rising inhibitor (TRI) to aeolian sand paste materials (ASPM) to produce paste-like filling mining materials can solve multiple problems. First, it may alleviate the environmental problems caused by solid waste treatment in mines to achieve sustainable use of solid waste. Second, It may solve the problem of rapid temperature rise in mines caused by the rapid heat release during filling body hydration. Therefore, this study explored the hydration of an ASPM with different TRI contents and its mechanical properties, setting time, and microstructure. The results show that at TRI contents of 0–1.0%, the peak heat-release rate of the ASPM is reduced by 16.0%, the early hydration heat release is reduced by 14.2%, and the delay of the heat-release peak is more prominent. TRI inhibits the hydration of ASPM primarily within 7 d, which reduces the early strength of the ASPM by a maximum of 43.4%. However, with the increase in age, the strength difference gradually decreases, and TRI even becomes beneficial for the development of strength in later stages. In addition, the high content of TRI has a significant retarding effect on ASPM hydration. The temperature rise test shows that TRI can reduce the temperature increase rate and delay the peak temperature increase rate, which can effectively solve the problem of concentrated heat release by backfill. This paper provides a theoretical basis for the application of TRIs in cemented paste backfill.

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

To solve the disposal problems of carbide slag (CS), soda residue (SR), and red mud (RM) solid wastes, a new type of cemented paste backfill (CPB) was prepared with CS, SR, and RM solid wastes. The mixing proportion for the CPB was optimized by combining the Box‒Behnken design (BBD) response surface method and the satisfaction function method. The strength formation mechanism for the CPB was analyzed with physical and mechanical property tests, X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), etc. The safety of the CPB was evaluated with heavy metal leaching testing. The results showed that the 28-day unconfined compressive strength (UCS) of CPB first increased and then decreased with increasing CS/RM (0.2 ~ 0.6) and SR/RM (0.2 ~ 0.6); the optimum mixing ratios were CS/RM = 0.45 and SR/RM = 0.37, and the solid mass concentration was 64.75%; dense calcium silicate (aluminum) hydrate (C-S–H/C-A-S–H) bound to the solid particles of red mud and filled pores to provide early strength for the CPB, laminar interwoven Friedel's salt (Fs), ettringite and portlandite hydration products provided late strength for the CPB; and the leaching concentrations of five heavy metals (Fe, Mn, Cu, Zn, and Cr) in the solidified CPB were greatly reduced and far below the leaching limits specified in China's Quality Standard for Groundwater (GB/T 14848–2017). [ABSTRACT FROM AUTHOR]

Organic rectorite (OREC) can significantly improve the resistance of asphalt to deformation and aging, but it tends to cause low-temperature cracking. To solve this defect, a novel idea that develops an OREC and polyurethane (PU) composite-modified asphalt binder has been put forward in this work. Various modified asphalt binder systems containing different combinations of OREC and PU contents were prepared by the melt blending method. The storage stability of the OREC/PU-modified asphalt binders was studied. The high- and low-temperature properties of binders were investigated by dynamic shear rheometer and bending beam rheometer tests. The microstructure and modification mechanism of the binders were characterized by gel permeation chromatography, differential scanning calorimetry, and Fourier transforms infrared spectroscopy. The results showed that the OREC/PU-modified asphalt binder displayed good high-temperature storage stability. However, excessively high content of OREC will adversely affect the storage stability of asphalt. In the 2% by weight OREC/9% by weight PU modified asphalt system, OREC and PU exhibited excellent synergistic effects. And the high- and low-temperature properties of the asphalt were significantly improved. The introduction of OREC/PU reduces the Tg of the asphalt binder and the enthalpy during temperature change. The modified asphalt has good low-temperature flexibility through the physical and chemical interaction between polyurethane and asphalt during the modification process. PU can intercalate OREC and react with active hydrogens in asphalt to generate cross-linked structures to enhance the high- and low-temperature properties of the asphalt binder. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving the performance of proton exchange membranes (PEMs) through the synthesis of sulfonated polymers with elaborate molecular structures has received extensive approval. However, the tedious synthetic process and consequently high costs restrain their possible substitution for Nafion, a classic PEM material. Herein, a series of semi-crystalline sulfonated poly(ether ketone)s with fluorene-based units were prepared via direct copolymerization of commercially available monomers and followed post-sulfonation, namely SPEK-FD-x, where × represents the molar ratio of the fluorene-containing monomer to the employed bisphenol monomers. The entire synthetic pathway was facile without involving hardly accessible materials. Subsequently, various properties of SPEK-FD-x membranes were investigated and further compared with Nafion 117. Due to the formation of the well-defined hydrophilic-hydrophobic microphase separation morphology and the reinforcement of the PEK crystalline regions, the SPEK-FD-x membranes exhibited outstanding proton conductivity, resistance for methanol permeation, as well as dimensional, thermal, oxidative, and mechanical stability. Among them, the overall behavior of the SPEK-FD-25 membrane was comparable to or even greater than that of Nafion 117, most importantly, it also performed decently in both H 2 /air fuel cells and direct methanol fuel cells. Therefore, with the straightforward synthesis and superior performance, the SPEK-FD-x membranes may serve as a promising alternative to Nafion. [ABSTRACT FROM AUTHOR]

This study investigates the microscopic morphology of a hydraulic servo spool valve caused by particle erosion. The microscopic morphology of spool working edges and solid particle characteristics in oil of a typical hydraulic servo system were experimentally studied. The formation mechanism was analyzed using dynamic impact calculation. The results reveal that the erosion micro-morphology of the spool working edge was mainly characterized by surface peeling, notches, grooves, and chamfers. The contour of the working edge was rounded. The average and variance of the radius of the old spool's working edges were obviously higher than those of the new spool. The main distribution range of solid particle size in typical servo-hydraulic system oil was 5–50 μm, and the number of particles decreased sharply with an increase in particle size, up to 90.89%. The actual shape of particles was close to an ellipsoid with strong erosion destructive power. When a single solid particle collided with the working edge, a large amount of stress was generated at the collision center point, and the stress can reach 1500 MPa when the pressure differential at the valve orifice was 3.5 MPa. The working edges were subjected to cyclic stress of high-frequency particle pulses, resulting in fatigue erosion. [ABSTRACT FROM AUTHOR]

Taking Chinese fir wood from plantation as the research object, three technological parameters including hot-pressing temperature (160, 180, 200 °C), hot-pressing time (20, 30, 40 min) and compression ratio (30%, 40%, 50%) were selected, and the compression densification modification test of Chinese fir was carried out by using the full factor experimental design. Based on the mechanical properties, microscopic morphology and crystallinity of wood, the effects of different processing parameters on wood properties were analyzed, and the densification process parameters of Chinese fir wood were optimized. The results showed that the properties of the densified wood prepared by Chinese fir were better under the technological conditions of hot pressing temperature of 180 °C, compression ratio of 50%, and pressing time of 40 min. The flexural strength, flexural modulus of elasticity, tensile strength, and hardness of the densified Chinese fir were 130.4 MPa, 12 338 MPa, 113.1 MPa and 1 631 N respectively, which increased by 112%, 113%, 44%, and 55% compared to the untreated wood. The scanning electron microscope observation showed that almost all the early wood cells were crushed, and there were regular folds along the direction of the wood ray, while some of the late wood cells were crushed, and most of them kept the original cavity structure. The hardness and elastic modulus of the cell wall of the densified wood were 16.7% and 45.7% higher than that of the untreated wood. The crystallinity of wood after compression treatment increased. The crystallinity of cellulose in the untreated wood and compressed Chinese fir was 46% and 53%, respectively. [ABSTRACT FROM AUTHOR]

The taxonomy of the enigmatic dark-mouth skate, Bathyraja arctowskii (Dollo, 1904), from the Southern Ocean was finally resolved after more than 100 years of ambiguity in 2021. This species is the smallest known species of the species-rich deep-water skate genus Bathyraja Ishiyama, 1958, which attains a total length of only about 61 cm and appears to be a wide-ranging and locally common species in the Southern Ocean. It differs from its congeners in the small adult size, dark-pigmented mouth cavity and underside of nasal curtain, lack of thorns on upper disc, as well as small and slender egg cases. Although the identity of this species was unambiguously clarified, the syntype egg cases could not be examined due to the COVID-19 pandemic. This examination has now become possible, and detailed data of the syntypes are provided in the present paper for the first time, together with hitherto unknown details of tooth, dermal denticle and thorn morphology. Furthermore, a lectotype and two paralectotypes are designated from the syntypes. [ABSTRACT FROM AUTHOR]

Slag is one of the main by-products of domestic waste incineration process. It not only has engineering properties comparable to those of natural stone commonly used in road engineering, but also has the hydration properties of cementitious materials, which has received high attention in the field of road engineering materials and solid waste resource utilization, and has gradually developed into an emerging green construction material. This paper reviews the microscopic morphology and structure, leaching characteristics and basic properties of slag, shows the feasibility of slag as a pavement aggregate, and presents the current problems faced by slag aggregates to achieve large-scale applications. [ABSTRACT FROM AUTHOR]

In order to investigate synergistic cementing effect between binary solid waste, the mechanical properties of the steel slag-red mud-cement based composite mortar were investigated under different ratio conditions, and the hydration characteristics and microscopic morphology of composite mortar were characterized by hydration heat, XRD, TG-DTG, SEM, etc. The study results show that compared with pure cement group, single addition 30% (the following are mass fractions) steel slag inhibits hydration reaction of slurry, and reduces mechanical properties of mortar. On the basis of adding 30% steel slag alone, adding an appropriate amount of red mud can effectively reduce the negative impact of steel slag on the mechanical properties of mortar. The 28 d flexural strength and 28 d compressive strength of composite mortar are the highest when the steel slag is mixed with 15% and the red mud is mixed with 15%, which are 6. 8 and 39. 8 MPa, respectively. Compared with the group with single addition 30% steel slag, the 28 d flexural strength and 28 d compressive strength increase by 11. 5% and 20. 6%, respectively, mainly because the red mud not only plays the role of physical filling, but also provides the physical filling for hydration reaction of steel slag. The hydration reaction of steel slag provides a good alkaline environment, which promotes participation of steel slag in the hydration reaction and generates more calcium alumina and hydrated calcium silicate gel to improve the microstructure of mortar. [ABSTRACT FROM AUTHOR]

Epoxy asphalt mixture with the epoxy system (EPS) and basalt has excellent road performance, but due to its high price, epoxy asphalt mixture is limited in its applications in conventional pavement. In addition, the basalt aggregate commonly used in epoxy asphalt mixture has shortages of high cost and insufficient reserves. This paper tries to reduce the EPS content and select suitable aggregates to prepare epoxy asphalt mixture with good road performance for conventional pavement. Basalt epoxy asphalt mixture (BEAM) and limestone epoxy asphalt mixture (LEAM) were designed based on the Bailey method. The road performance of BEAM and LEAM was evaluated by the Marshall test, rutting test, low-temperature bending test, water stability test, and fatigue test. Meanwhile, the mechanism of the EPS on the road performance of the mixture was revealed by the laser scanning confocal microscopy test. The results showed that the high-temperature deformation resistance, water damage resistance, and fatigue resistance of BEAM and LEAM were improved with the increase of EPS content, but the low-temperature crack resistance of the two mixtures was slightly decreased. Especially when the EPS content was 35 wt%, the performance change of BEAM and LEAM was more significant, which was caused by the phase transition in epoxy asphalt (EA). Therefore, 35 wt% EPS was recommended in EA. In addition, compared with BEAM, LEAM had better low-temperature crack resistance, less favorable high-temperature deformation, and fatigue resistance. The addition of EPS availably decreased the difference in road performance between LEAM and BEAM. Meanwhile, LEAM showed obvious cost advantages over BEAM. The research results of this paper had positive significance for expanding the engineering application of epoxy asphalt mixtures. [ABSTRACT FROM AUTHOR]

In advanced packaging technology, the micro bump has become an important means of chip stacking and wafer interconnection. The reliability of micro bumps, which plays an important role in mechanical support, electrical connection, signal transmission and heat dissipation, determines the quality of chip packaging. Surface morphological defects are one of the main factors affecting the reliability of micro bumps, which are closely related to materials and bonding process parameters. In this paper, the electrodeposition process of preparing gold bumps is simulated at the atomic scale using the Kinetic Monte Carlo method. The differences in surface morphology and roughness of the plated layer are studied from a microscopic perspective under different deposition parameters. The results show that the gold micro bumps prepared by electrodeposition have better surface quality under conditions of lower deposition voltage, lower ion concentration and higher plating temperature, which can provide significant guidance for engineering applications. [ABSTRACT FROM AUTHOR]

To promote the resource utilization of steel slag and improve the production process of steel slag in steelmaking plants, this research studied the characteristics of three different processed steel slags from four steelmaking plants. The physical and mechanical characteristics and volume stability of steel slags were analyzed through density, water absorption, and expansion tests. The main mineral phases, morphological characteristics, and thermal stability of the original steel slag and the steel slag after the expansion test are analyzed with X-ray diffractometer (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TG) tests. The results show that the composition of steel slag produced by different processes is similar. The main active substances of other processed steel slags are dicalcium silicate (C2S), tricalcium silicate (C3S), CaO, and MgO. After the expansion test, the main chemical products of steel slag are CaCO3, MgCO3, and calcium silicate hydrate (C-S-H). Noticeable mineral crystals appeared on the surface of the steel slag after the expansion test, presenting tetrahedral or cigar-like protrusions. The drum slag had the highest density and water stability. The drum slag had the lowest porosity and the densest microstructure surface, compared with steel slags that other methods produce. The thermal stability of steel slag treated by the hot splashing method was relatively higher than that of steel slag treated by the other two methods.

To perform an in-depth study of the crystal growth habits and phase changes of alumina and its precursors in reaction systems, this paper studied the effects of reactant type and addition order on the morphology of alumina using hydrothermal methods with different precipitants and aluminum sources as reactants. Research has shown that sodium bicarbonate and ammonium bicarbonate can be used as precipitants to prepare adhered spherical alumina and irregular short rod alumina, while potassium bicarbonate can be used as a precipitant to prepare hexagonal flake alumina. Using aluminum sulfate octahydrate, aluminum chloride hexahydrate, and aluminum nitrate, nine hydrates were prepared as aluminum sources, and agglomerated alumina, irregular short rod-shaped alumina, and fused alumina were obtained. The order of reactant addition affects the precursor phase of alumina, thereby affecting the microstructure of alumina after calcination, resulting in flake alumina with pores and short rod alumina. The results of this paper will provide theoretical guidance for the preparation of alumina with different micromorphologies.

This study examines a versatile polymer known as polysurfactant, which is synthesized by co-polymerizing flexible acrylamide and sodium acrylate hydrocarbon chain. The polymer serves as a backbone and possesses active functional groups. Notably, the polysurfactant exhibits superior plugging and flooding abilities compared to conventional polymers. The primary objective of this paper is to investigate the properties and oil displacement characteristics of the polysurfactant through indoor physical simulation experiments. The results demonstrate that the multi-branched structure of the polysurfactant enhances its ability to associate, leading to the formation of a unique spatial network structure. The inclusion of multi-branched structures notably amplifies the association effect. The critical concentration for the association is estimated to be around 800 mg/L, at which juncture the polysurfactant exhibits a viscosity retention rate surpassing 90% subsequent to shearing. Furthermore, this spatial network structure exhibits self-recovery capabilities after experiencing shear failure and displaying strong viscosity and shear resistance. In addition, the concentration of the polysurfactant can control the hydrodynamic feature size, which shows its adaptability in regulation and oil-repelling functions at reservoir permeabilities ranging from 500 to 2000 × 10−3 μm2 with resistance coefficients ranging from 108 to 320. During the microscopic oil displacement process, the polysurfactant exerts a significant impact on mobility control, while the elastic pull clearly demonstrates a commendable viscoelastic oil displacement effect. The polysurfactant exhibits a specific degree of emulsification capability towards crude oil, leading to the emulsion exhibiting typical pseudoplastic fluid characteristics. The utilization of emulsification transportation and emulsification blockage contributes to the enhancement of oil recovery. As a result, the polysurfactant exhibits multifaceted capabilities, encompassing profile control, flooding, and plugging, owing to its unique structural characteristics. Through the implementation of a field test focused on flooding in the Daqing Oilfield, a significant enhancement in the recovery rate of 10.85% is observed, accompanied by a favorable input–output ratio of 1:3.86, thereby generating significant economic advantages.

Porphyrins and their derivatives have been employed extensively in organic solar cells (OSCs) in recent years. However, a deeper understanding of the exciton dissociation process for the porphyrin donor/non‐fullerene acceptor (NFA) interface is still lacking. Herein, we have combined quantum chemistry and molecular dynamics simulations to explore the combination of mono and dimer porphyrin donors with various types of NFAs. The work reveals that the key issue lies in the exciton dissociation process of porphyrin materials, which have strong crystallinity to increase spacing (more than 5.0 Å), resulting in lesser miscibility and weaker intermolecular π‐π stacking. The pathway for exciton dissociation will be limited by the small number of high‐energy charge transfer (CT) states. To solve the above‐mentioned issues, we implement an improved strategy for modifying the side chain of the terminal unit, reducing the stacking distance to 4.4 Å, while the number of CT states reaches up to 40 % (3/A3 style 1). Additionally, the results also indicate the development potential for all porphyrin OSCs, particularly, the charge recombination (kCR) rate of the 1/Rf‐Iso system is lowered by nearly nine orders of magnitude. This research may offer fresh perspectives for extending the application range of porphyrin materials in OSCs. [ABSTRACT FROM AUTHOR]

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

In this paper, a nano functional agent HXG-36-8 without harmful substances and radiation source was prepared. By means of SEM, XRD, EDS, XRF, eye irritation test, skin irritation test, acute oral toxicity test, antibacterial test and antiviral test, the micromorphology observation, phase structure analysis, composition analysis, biological toxicity test, antibacterial test and antiviral test were carried out. Hxg-36-8 has flake nanoscale microscopic morphology and crystal structure of wurtzite zinc oxide. It has no irritation to rabbit eyes and rabbit skin and is actually nontoxic. In addition, the antibacterial product prepared with HXG-36-8 as antibacterial agent has an antibacterial rate of 99.0% against Escherichia coli and an anti-novel coronavirus activity rate of over 98.87%. The results showed that the functional agent is safe, nontoxic, has good antibacterial and antiviral function, can be used in all kinds of products in contact with human body, including clothing, protective articles, dental ceramic materials, etc. [ABSTRACT FROM AUTHOR]

Laminated metal composites have attracted more attention due to their ultra-high strength, fracture toughness and elongation, full considerations of each component, and coordinated deformation effect between interfaces. Herein, Zn and Al were selected as the component materials to prepare Al/Zn laminated composite plates using hot rolling and low temperature annealing, and studied the influence of the thickness of the diffusion layer at the interface to understand the reason for the strengthening and toughening mechanism. The results show that, with an increase in annealing temperature and time, the grain will recover and recrystallize to grow. A diffusion layer with a certain thickness formed at the interface due to the mutual diffusion of Al and Zn atoms at the interface. As annealing time and temperature increase, the yield and tensile strengths first increased and then decreased. The tensile fracture morphology showeds many deep dimples. In the rolling state, the micro-hardness value at the interface was between Al and Zn. [ABSTRACT FROM AUTHOR]

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

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