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The equal molar AlCoCrFeNi high entropy alloys with 5% (volume fraction) TiB2 particles reinforcement were fabricated by spark plasma sintering (SPS). Effect of SPS temperature and pressure on microstructure evolution and mechanical properties of TiB2/AlCoCrFeNi composites was studied using X-raydiffraction (XRD), density testing, scanning electron microscopy (SEM) and mechanical properites testing. The results show that increasing SPS temperature and pressure can improve hardness and compressive strength of TiB2/AlCoCrFeNi composites. The relative density, compressive strength, yield strength and hardness of the TiB2/AlCoCrFeNi composite after sintering at 1200℃ and 30MPa are 99.6%, 2416MPa, 1474MPa and 470HB, respectively. During spark plasma sintering, phase transformation occurs in the high entropy alloy matrix of the composite. The composite after sintering at 1200℃ and 30-45MPa is composed of phases BCC, B2, FCC, TiB2 and σ.

The purpose of this study is to improve the number and distribution of active particles on the MAO layer by changing the activation method, thus improving the corrosion resistance of the coating. The structure of the coatings was characterized by SEM, XRD, XPS, and AFM, as well as the corrosion resistance of the coatings by polarization curves, EIS tests, immersion tests, and salt spray tests. The conductive resistance and adhesion of different composite coatings were compared. The results demonstrate that the properties of the composite coating are significantly affected by different activation methods, and the Ni-P coating prepared with more active particles offers superior corrosion protection to the inner layer. The quantity and distribution of active particles affect the compactness of the coating by influencing the initial deposition process. The size of nickel particles is larger and the inter-grain porosity increases in the case of fewer active sites, and as the number of active sites increases, the size of nickel particles decreases, and the coating compactness increases. The mechanism of the effect of the number of active particles on the deposition process of electroless Ni-P coating was proposed. [ABSTRACT FROM AUTHOR]

The high strength of 300M steel originates from the heat treatment process after forging, but how hot deformation affects the heat-treated microstructure and mechanical properties is unclear. In this study, compression tests under different hot deformation parameters and post-deformation heat treatment experiments were carried out, and the martensite transformation process was investigated using in situ observation. The results show that the grain size of the specimen deformed at low temperature and high strain rate is smaller, and annealing twins will be formed. Both austenite grain boundaries and twin boundaries hinder the growth of martensite blocks, reducing the size of martensite units after heat treatment and thus resulting in higher yield strength. Besides, the mathematical models were established to describe the relationship between hot deformation parameters and grain size after deformation, martensite packet size and martensite block width, respectively, after heat treatment. The relationship between yield strength and hot deformation parameters was also analyzed. According to the results and models, the hot deformation parameters would be optimized more reasonably to improve the final mechanical properties of 300M steel forgings. [ABSTRACT FROM AUTHOR]

As a high-efficiency and high-quality welding technology, laser-tungsten inert gas (laser–TIG) hybrid welding has been widely used in the aerospace and marine equipment industries. Through laser–TIG hybrid welding of TC4 titanium alloy, the effect of the current on the weld formation, the microstructure and mechanical properties of the arc zone, and the laser zone was studied. The results show that the molten pool in the arc zone will flow periodically, and the flow becomes more intense with an increase in the current, which will result in a finer grain size in the arc zone than in the laser zone, having the effect of eliminating pores. The spacing of the α′ martensite beams in the laser zone is narrower, with an average spacing of 0.41 μm. The β phase increases gradually with the increase in the current, which will lead to a downward trend in the average hardness of both zones. The average hardness value of the laser zone, containing more α′ martensite and less β phase, is slightly higher than that of the arc zone. The hardness uniformity of the laser zone is also significantly better than that of the arc zone. The tensile strength of the joint shows a trend of increasing first and then decreasing, and the joint with I = 50 A presented the highest tensile strength of 957.3 MPa, approaching 100% of the base metal, and fractured in the fusion zone. [ABSTRACT FROM AUTHOR]

Superalloys are widely used in industries such as aerospace, nuclear power, and oil and gas, owing to their exceptional high-temperature and corrosion-resistant properties. Since the creep life of superalloys is controlled by material microstructure, the quantitative analysis of microstructures using image segmentation technology is essential for building the relationship between the characterization of microstructure and the properties and performances of alloys. However, there still remain challenges as the mutual occlusion phenomenon among multiple phases during their preparation makes accurate microstructure segmentation difficult. For example, the precipitate always occludes the grain boundary, resulting in the over-segmentation of grains and hindering the accurate characterization of microstructure. Therefore, we propose a novel method Multi-phase U-Net, dubbed as MPU-Net, to effectively detect the grain boundaries and precipitate at the same time in an end-to-end manner. In addition, we design two post-processing strategies to further improve boundary detection results. Extensive experiments were performed using the OM images and FESEM images to evaluate the performance of the proposed method. The study concluded that the proposed method outperforms existing approaches in both quantitative and qualitative results, and achieves superior performance in characterizing the analysis. The experimental study demonstrates the potential for utilizing the proposed method to efficiently automate microstructure analysis, requiring minimal labor and offering cost-effective solutions. • MPU-Net for end-to-end simultaneous grain boundary and precipitate detection. • Pruning eliminates misclassified unclosed boundaries detected by deep learning. • Redistribution corrects boundary over-segmentation caused by precipitate occlusion. • Promising performance in objective and subjective assessment across two datasets. [Display omitted] [ABSTRACT FROM AUTHOR]

Ternary Cu‐Fe‐Si alloy were applied to modify tribological behavior of carbon fiber/carbon‐silicon carbide (Cf/C‐SiC) composites by reactive melt infiltration. Microstructures, physical properties and tribological properties on a full‐scale train brake test rig of the modified composites were studied. Results indicate that both Cu and Fe‐Si alloy as matrices lead to significantly enhanced thermal conductivity and compressive strength for Cf/C‐SiC composites. Moreover, the average friction coefficient of the modified composites is between 0.25 and 0.55, which is higher than that of copper metal matrix composites. In addition, the average volume wear rate of the modified composites is only 0.168 cm3/MJ. The Cf/C‐SiC composites modified by Cu and Fe‐Si alloy with improved physical properties and tribological properties meet the technical requirement and show high application potential in express train brake systems. [ABSTRACT FROM AUTHOR]

Two pretreatment method, including the normal activation and the ultrasonic agitation in acidic bath, were used during the pretreatment of AZ91D substrate, for which the electroless Ni-W-P coating was prepared. The microstructure, bonding strength and corrosion resistance were compared. The effect of different activation condition on the microstructure and corrosion resistance was investigated and discussed. Results demonstrate that ultrasonic agitation has negligible effect on the microstructure, chemical composition, but improves the bonding strength and corrosion resistance of Ni-W-P coating. The corrosion resistance of Ni-W-P coating via ultrasonic pretreatment was less dependent on the deposition time. Ultrasonic agitation facilitates the deposition of Ni on the β phase and the eutectic phase, and improves the compactness at Mg/Ni interface by decreasing the inclusion of MgF 2 , which are critical for improving the quality of Ni-W-P coating. • Ultrasonic agitation (UA) was applied on AZ91D to prepare Ni-W-P coating. • Chemical composition and structure were not affected by UA. • The corrosion resistance and bonding strength were improved by UA. • The corrosion resistance of coating by UA was independent on deposition time. • UA improves the corrosion resistance by removing the activation products. [ABSTRACT FROM AUTHOR]

We investigated the changes in microstructure and composition of milk fat globule membrane (MFGM) in fresh human milk under different storage temperatures (-18, -3, -0.5, and 4 °C). Freezing at -18 °C resulted in the formation of ice crystals that ruptured the MFGM, leading to aggregation and increased particle size, which could potentially impact lipid digestion and absorption in infants. Conversely, storage at -3, -0.5, or 4 °C were more favorable for maintaining the stability of MFGM structure without ice crystals formation. Notably, -3 °C exhibited the highest preservation of MFGM integrity. Label-free proteomics analysis identified a total of 1525 different MFGM proteins in the initial sample (0 day) and samples preserved at varying temperatures (-18, -3, -0.5, and 4 °C) for a duration of 4 days. Principal component analysis and hierarchical clustering analysis demonstrated two distinct clusters of MFGM proteins across the different storage temperatures. Specifically, MFGM proteomic characteristics at -18 and -3 °C showed more similarities and clustered together with the 0-day samples, while -0.5 and 4 °C formed a separate cluster. Comparative analysis with the control sample (day 0) highlighted significant changes in 202 proteins, most of which played essential roles in binding, catalytic activities, and pathways related to protein, lipid, and fatty acid metabolism. Our findings highlight the superior ability of -3 °C to inhibit bacterial growth compared to 4 and -0.5 °C, and to preserve the microstructure of milk fat globules compared to -18 °C. Thus, for household storage up to 4 days, we recommend a temperature of -3±1 °C, considering temperature fluctuations in domestic refrigerators. [Display omitted] • Ice crystals formed in human milk under -18 ℃ caused the fracture of MFGM structure. • The rupture of MFGM caused the change of particle size and distribution of HMFG. • Storing human milk at -3°C (±1°C) prolongs the short-term storage up to 7 days. [ABSTRACT FROM AUTHOR]

Mo-Si-B composites with boron content from 0 to 8 wt.% were prepared by spark plasma sintering using Mo, Si, and B elemental powders. The effects of boron content on the phase composition, mechanical properties, and high-temperature oxidation resistance of the Mo-Si-B composites were investigated. The results show the evolution of the major phase constitution of the composites with increasing boron content is in the following sequence: (MoSi2, Mo5Si3) → (MoSi2, Mo5Si3, Mo5SiB2) → (MoSi2, MoB) → (MoSi2, MoB, MoB2). As the boron content increases, both the hardness and flexural strength of the composites increases, but the fracture toughness of the composites gradually decreases. The strengthening mechanisms for the composites are second-phase strengthening and grain refinement strengthening. However, the formation of brittle phases, i.e., Mo5SiB2, MoB, and MoB2, reduces the toughness of the composites. In addition, since a dense barrier layer of SiO2-B2O3 formed on the surface of the composites inhibits the inward diffusion of oxygen, B-doped Mo-Si-B exhibits better oxidation resistance compared with non-doped composites. [ABSTRACT FROM AUTHOR]

Based on a critical evaluation of experimental diffusion data available in the literature and the updated thermodynamic descriptions within the CALPHAD framework, the atomic mobilities of U, Nb, Ti, and Zr in U-X(X=Nb, Zr, Ti) bcc alloys were assessed with the DICTRA software. For each system, comprehensive comparison shows that a good agreement between the calculated and experimental data was obtained. The developed mobilities in conjunction with the thermodynamic parameters were also used to describe the marker movement in the U/Zr as well as U/Ti diffusion couples, and a satisfactory result was obtained. The presently obtained atomic mobilities can describe diffusion phenomenon more accurately than previously reported atomic mobilities. [ABSTRACT FROM AUTHOR]

The whole C–Zr–Nb ternary system was assessed by means of CALPHAD method for the first time. All of the experimental phase diagram data available from the literature were critically reviewed and assessed using thermodynamic models for the Gibbs energies of individual phases. The solution phases including the liquid, fcc, hcp and bcc were described by the substitutional solution model. There is no ternary compound in this system. A set of self-consistent thermodynamic parameters for the C–Zr–Nb system is obtained. Comparisons between the calculated and measured diagrams show that the present thermodynamic description can account for the experimental information satisfactorily. The liquidus projection and reaction scheme for the C–Zr–Nb system were generated by using the present thermodynamic parameters. The effect of microstructure on the mechanical properties of C–Zr–Nb alloys homogenized at 1800 °C reported in the literature was discussed from a phase diagram point of view. [ABSTRACT FROM AUTHOR]

In this work, specimens of the 2024 aluminum alloy sheet were compressed and stretched along the original rolling direction at elevated temperatures. The microstructure evolution was investigated by characterizing the metallographic structures via electron backscattered diffraction technology before and after deformation. It was found that while recrystallization occurred in the compressed specimens, it was not observed to the same extent in the stretched specimens. This difference in the grain morphology has been attributed to the different movement behaviors of the grain boundaries, i.e., their significant migration in the compression deformation and the transformation from low-angle to high-angle boundaries observed mainly during tension deformation. The empirical model, which can describe the grain size evolution during compression, is not suitable in the case of tension, and therefore, a new model which ignores the detailed recrystallization process has been proposed. This model provides a description of the grain size change during hot deformation and can be used to predict the grain size in the plastic deformation process. [ABSTRACT FROM AUTHOR]

The composite ceramics of BaBiSnTiO (BBST) with x wt.% MgO (0 ≤ x ≤ 30) were prepared by solid-state sintering. The effects of MgO content on the microstructure and dielectric properties of the composite ceramics have been investigated. The results show that MgO is uniformly distributed in BBST matrix and enhances the relative density of composite ceramics remarkably, which effectively optimizes the performances of dielectric loss, alternating current (AC) breakdown strength (BDS) and insulation. With the content of MgO increasing from 0 wt.% to 30 wt.%, the dielectric constant decreases from 2900 to 920, dielectric loss decreases from 0.011 to 0.0065, BDS is improved from 26 kV/cm to 53.6 kV/cm and leakage current density decreases from 2.96 × 10 A/cm to 9.55 × 10 A/cm. The ceramic added with 30 wt.% MgO exhibits the best comprehensive dielectric properties, which is a superior dielectric used in high-voltage ceramic capacitors. [ABSTRACT FROM AUTHOR]

The communication data are becoming increasingly important for criminal network analysis nowadays, and these data provide a digital trace which can be regarded as a hidden clue to support the crack of criminal cases. Additionally, performing a timely and effective analysis on it can predict criminal intents and take efficient actions to restrain and prevent crimes. The primary work of our research is to suggest an analytical process with interactive strategies as a solution to the problem of characterizing criminal groups constructed from the communication data. It is expected to assist law enforcement agencies in the task of discovering the potential suspects and exploring the underlying structures of criminal network hidden behind the communication data. This process allows for network analysis with commonly used metrics to identify the core members. It permits exploration and visualization of the network in the goal of improving the comprehension of interesting microstructures. Most importantly, it also allows to extract community structures in an appropriate level with the label supervision strategy. Our work concludes illustrating the application of our interactive strategies to a real-world criminal investigation with mobile call logs. [ABSTRACT FROM AUTHOR]

A series of Li2 CO3-added ( Ba0.95 Ca0.05)( Ti0.90 Sn0.10) O3 ( BCTS) ceramics were prepared by normal sintering at a low temperature of 1300°C; Their microstructure and electrical property evaluation were investigated with special emphases on the effect of Li2 CO3 addition. Adding Li2 CO3 significantly improves the sinterability of BCTS ceramics, resulting in a reduced sintering temperature by more than 150°C. The coexistence of R and T phases is confirmed by the Raman spectrum at room temperature for all samples and at a temperature range from −80°C to 40°C for sample with 3% mol Li2 CO3 addition. The specific ratio of R to T phase decreases with increasing temperature or Li2 CO3 addition. A higher εr is observed in T phase compared to R phase in the studied BCTS system. Better properties with d33 = 485 pC/N, kp = 39%, and Qm = 191 were obtained for BCTS sample with 3% mol Li2 CO3 addition, which is attributed to the increased grain size and density along with the variation in the specific ratio of R to T phase. [ABSTRACT FROM AUTHOR]

Highlights: [•] Water sorption isotherms of the three WPH powders fitted the GAB model well. [•] An increase in water content or degree of hydrolysis caused the decrease in Tg. [•] Particle collapse and bridging occurred at high relative humidity or temperature. [•] Color change might be caused by microstructure change other than Maillard reaction. [•] State diagram is developed to understand physicochemical stability of WPH powder. [ABSTRACT FROM AUTHOR]

Gas tungsten arc welding (GTAW) is a widely used joining technique due to its low welding cost and flexible process. To promote the application of titanium/copper dissimilar metal welded structure, the microstructures and properties of TA2 titanium and T2 copper butt joint prepared by GTAW with pure copper filler metal (S201) and Cu–Al filler metal (S214) were systematically investigated. The microstructures of the joints were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the properties of the joints were evaluated by tensile, microhardness and electrochemical corrosion tests. The results suggested that the intermetallic compound layers of S201 filler metal weld joint were composed of rod-like Ti 2 Cu, plate-like TiCu, needle-like TiCu and a small amount Ti 3 Cu 4. While plate-like TiCu were not found when using S214 filler metal. Moreover, the weld joint with S201 filler metal displayed a better plasticity and a higher tensile strength having 73.0% tensile strength of copper base metal. The electrochemical corrosion tests indicated that Al elements in weld joint with S214 filler metal could inhibit the cathodic reaction, and decrease the dissolution of weld seam metal. [ABSTRACT FROM AUTHOR]

This study investigates the effects of particle size (22.4 and 7.5 μm diameters) and aging history (40 °C, 20 days) of milk protein concentrate (MPC) powders on their rehydration properties as well as the biophysical properties including molecular migration, microstructure, and texture of a high-protein nutrition bar (HPNB) made using these MPC powders. It was observed that the rehydration properties (wettability and solubility) of MPC powders decreased with aging but increased with the decrease in the MPC particle sizes. The migration of small molecules (water, glycerol and sorbitol) was slower for HPNB formulated with aged powders of the same sizes but faster for those formulated with small-sized powders of the same aging history. Plasticization of powder particles was lesser for HPNB formulated with aged powders having the same sizes, but greater for those formulated with small-sized powders with the same aging history. The increase in hardness during storage was smaller for HPNB formulated with fresh and small-sized powders, compared to those formulated with aged and large-sized powders. The cohesiveness was higher for HPNB formulated with small-sized powders, compared to those formulated with large-sized powders. These results suggest that the reduction of the MPC powder particle size by manipulating the spray airflow rate offers a potential route to manipulate the textural properties of HPNB. • MPC powder rehydration decreased with aging and with particle size increase. • Molecular migration was faster for HPNB containing small MPC particle size. • Plasticization of particle was greater for HPNB containing small MPC particle size. • Hardness increase with storage was smaller for HPNB with small MPC particle size. • Cohesiveness was higher for HPNB containing small MPC particle size. [ABSTRACT FROM AUTHOR]

The influence of κ-carrageenan (KC) was investigated on the microstructure of gels formed by acid-induced gelation of whey protein aggregates (WPA). In part I of this two-part series we discussed results obtained by potentiometric titration, rheology and turbidimetry. Here we report on the microstructure of both the proteins and the polysaccharides using confocal laser scanning microscopy with different fluorescent labels for each type of biopolymer. The effect of KC concentration at fixed net protein charge densities (α) and the effect of α at fixed KC concentrations were studied. It is shown that WPA starts to form microdomains and associates with KC at approximately the same α. Microstructures at steady state at different α were compared with those obtained at different times during in-situ acidification after addition of GDL. Significantly different microstructures were observed at elevated gelation temperatures. Fluorescence recovery after photobleaching measurements showed that a significant fraction of the KC chains associated with the proteins could still freely exchange even when the proteins were strongly positively charged. The observations of the microstructure are compared with those obtained with other experimental techniques that were reported in part I. Image 1 • Kappa carrageenan forms complexes with whey protein aggregates during acidification. • The distribution of KC and whey protein can be monitored by specific fluorescent labeling. • No segregative phase separation occurs between KC and WPA during acid induced gelation. • During acidification complexation starts at the same protein charge density as gelation. [ABSTRACT FROM AUTHOR]

The influence of the Co/SBA–15 catalyst texture, such as pore size and pore length on Fischer–Tropsch (FT) Synthesis, was investigated in this paper. The morphology, structure, and microstructures of Co/SBA–15 catalysts were characterized by SEM, Brunauer–Emmett–Teller (BET), TPR, HRTEM, and XRD. The experimental results indicated that the increase of pore size could improve the activity of the Co/SBA–15 catalyst, and the further increase of pore size could not significantly promote the activity. Moreover, it was also found that the pore length of the Co/SBA–15 catalyst played a key role in the catalytic activity. CO2 and C4+ selectivity were 2.0% and 74% during the simulated syngas (64% H2: 32% CO: balanced N2) FT over the Co/SBA–15 catalysts, and CO conversion rate and CH4 selectivity were 10.8% and 15.7% after 100 h time on stream. [ABSTRACT FROM AUTHOR]

The optimization of the sintering process for ceramic stereolithography-based additive manufacturing is attracting high interest important due to its correlation with the final properties of the fabricated parts. In this work, a photosensitive zirconia suspension with low viscosity and high solid loading (48 vol%) was prepared using surface-modified zirconia ceramic powders, resulting in an improvement in long-term stability. The correlations between the sintering temperature (1400–1520 °C) and mechanical properties were investigated. The results showed that and the as-sintered zirconia parts exhibited a relatively high density of 99.5 ± 0.1 % and three-point flexural strength of 821 ± 65 MPa as well as excellent fracture toughness (4.37 ± 0.22 MPa m1/2) sintering at 1480 °C, which was attributed to the highly homogeneous microstructure without obvious pores or crack. The obtained insights regarding the correlation between sintering temperature, relative density, and flexural strength can provide practical guidance for the future applications of zirconia ceramics. [ABSTRACT FROM AUTHOR]

Mo and Al2O3-Mo coatings are fabricated on a low-carbon steel substrate using atmospheric plasma spraying. The microstructure and mechanical properties of two as-sprayed coatings, with a particular focus on the tribological behaviors from room temperature to 300 °C, are comparatively investigated in this study. Microstructural analysis of the coatings shows that the porosity of the Al2O3-Mo coating is higher than that of Mo coating. The addition of Al2O3 particles reduces the coating–substrate adhesion strength. The Al2O3-Mo coating, in comparison to the Mo coating, shows improved mechanical properties, such as hardness and wear resistance. The friction coefficients of both coatings increase with further increases in test temperatures. The friction coefficient of the Al2O3-Mo coating, tested above 100 °C, is lower than that of the Mo coating. The wear failure mechanisms of the two coatings are delamination, brittle fracture, oxidation and adhesion wear. In addition, local plastic deformation was also found in the Mo coating. [ABSTRACT FROM AUTHOR]

Abstract The size-dependent microstructural evolution behavior has a significant impact on the thermoplastic flow behavior of metallic glass in the supercooled liquid region. In this work, double-cup extrusion tests, corresponding finite element method simulations and nanoindentation measurements of Zr 55 Cu 30 Al 10 Ni 5 metallic glass samples with different sizes, are employed to study the relationship between the size-dependent free volume variations and thermoplastic flowability. Experimental results and theoretical analyses demonstrate that the free volume content increases with increasing sample size. The change tendencies of free volume content and micro-hardness are in a negative correlation. The variation regularity of extruded cup height ratio verifies that the thermoplastic flowability of Zr-based metallic glass is enhanced with rising sample size. Furthermore, the size-dependent free volume variations and distributions induced by internal microstructural evolution behaviors result in the evident variations of micromechanical properties. The results of this study will contribute to a more in-depth understanding of the size-dependent thermoplastic deformation behavior of Zr-based metallic glass. Highlights • Thermoplastic flow ability of Zr-based metallic glass rises with rising sample size. • The ratio of upper and lower cup heights decreases with sample size rising. • The average free volume distribution increases with sample size increasing. • The free volume and micro-hardness change regularities are in a negative correlation. [ABSTRACT FROM AUTHOR]

Based on thermodynamic calculations and a concept of miscibility gap, a new type of double-layer gradient WC–Co–Ti(C,N)–ZrC cemented carbides is prepared through liquid-phase sintering under vacuum at 1465 °C for 1 h. The core of the prepared cemented carbides consists of WC, (Co) binder phase and miscibility gap (Ti-rich and Zr-rich cubic phases), in addition to the surface layer (WC and Co-rich binder phase) and second layer (WC, binder phase and Ti-rich cubic phase). The prerequisite and mechanism for the formation of double layers have been clarified by means of microstructure characterization and thermodynamic calculations. [ABSTRACT FROM AUTHOR]

This study explores the development of a novel alkali-activated cementitious material (APKC) using Pisha sandstone and slag as the main raw materials, offering a sustainable alternative to traditional cement. The APKC's flowability and mechanical properties are comparable to those of ordinary Portland cement (OPC), but it is significantly more cost-effective, with lower carbon emissions and energy consumption. Specifically, at a water-to-binder (w/b) ratio of 0.3, with an optimal activator content of 17.5 % and a Pisha sandstone-to-slag ratio of 1:1, APKC achieves excellent performance: a flowability of 195 mm, and 28-day compressive and flexural strengths of 59.1 MPa and 9.96 MPa, respectively. Moreover, the production of one ton of APKC reduces costs to 64.01 %, carbon emissions to 22.76 %, and energy consumption to 28.56 % of those associated with one ton of OPC, highlighting its potential as a viable replacement in engineering applications. The primary hydration products of APKC include hydrotalcite, C,N-A-S-H gels, C-S-H gels, and natrolines. It is crucial to maintain the alkali activator content and Pisha sandstone-to-slag ratio within optimal ranges, as insufficient alkali dosage or an excessive Pisha sandstone-to-slag ratio can diminish the mechanical properties by reducing hydration product content. Conversely, too much alkali activator can lead to high-porosity hydration products due to the dissolution of Al in C,N-A-S-H gels. • Utilizing Pisha sandstone as a precursor for alkali-activated cement offers a sustainable alternative to conventional cement. • This practice significantly reduces energy consumption and CO2 emissions associated with cement production. • The reaction mechanism of the new alkali-activated cement was investigated. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) nanosheets were synthesized through a facile two-step roasting process by using boric acid and melamine as raw materials under ammonia atmosphere. The average thickness of the nanosheets was 16 nm. The porous h-BN nanosheets displayed enhanced performance for the removal of copper ion (Cu 2+ ) with adsorption capacity up to 819 mg/g. In addition, the excellent performance was also observed during the process of the adsorption in mixed metal ions. The features of numerous amino connections, large specific surface area (∼321 m 2 /g) and broad range of pore size led to the outstanding adsorption performance. [ABSTRACT FROM AUTHOR]

Synchrotron X-ray radiography was used to in situ study the interface diffusion behavior and microstructural evolution during the melting and solidification of Al/Cu bimetal. During the solidification, the dendritic growth around the interface is mainly dominated by the variation of Cu concentration and thermal field. Four transition zones of solute profile around the interface were identified to be I (α-Al), II (Al + Al 2 Cu), III (Al 2 Cu) and IV (AlCu, Al 3 Cu 4 and Al 2 Cu 3 ), respectively. During the melting, the concentration variations of Al and Cu around the interface were quantitatively analyzed through the extraction of gray level from sequenced X-ray images. The diffusion coefficients of Cu in liquid Al were calculated from the known concentration variations by an inverse method based on Fick’s second law. The diffusion coefficients of Cu in Al were found to follow linear Arrhenius equation dependencies with the pre-exponential factor of 2.83 × 10 −5 m 2 s −1 and the activation energy of 96.0 kJ mol −1 in a temperature range of 893–970 K. [ABSTRACT FROM AUTHOR]

Highlights: [•] CdS with various morphologies prepared by solvothermal method. [•] Solvent influencing morphology and photocatalytic H2-production activity of CdS. [•] The highest H2-production activity observed for CdS nanowires. [Copyright &y& Elsevier]

Abstract: The CALPHAD technique is a powerful tool for materials processing and alloy design. The quality of CALPHAD-type calculations is strongly dependent on the quality of the thermodynamic database. In this paper, a self-consistent thermodynamic database for multicomponent cemented carbides has been developed. The thermodynamic descriptions for all of the binary systems and some of the ternary systems are taken from the literature with slight modifications for some of the reported parameters. A large number of ternary systems are assessed or reassessed under the consideration of experimental data and/or the consistency of the database. Assessments of some higher-order systems are performed based on experimental information, in particular focusing on commercial cemented carbide systems. Some examples of simulations for different kinds of cemented carbides are shown using the thermodynamic database and compared where possible against experimental data, thereby validating its accuracy. [Copyright &y& Elsevier]

The effect of enzymatic dephosphorylation, using intestinal alkaline phosphatase, on the structure of casein micelles in caprine micellar casein concentrate (MCC) was studied. An optimal condition, involving preheating the MCC dispersion, pH 6.4, 2.5 mg casein/mL and 0.4 U phosphatase/mL, was established and used to prepare MCC with 0–49% dephosphorylation by incubation at 37 °C for 0–180 min. β-Casein showed marked dephosphorylation and formed multi-phosphorylated isoforms depending on dephosphorylation degree, whereas α s - and κ-caseins showed limited and fast dephosphorylation, respectively. With increasing dephosphorylation, both the colloidal calcium and the calcium sensitive micellar caseins, especially β-casein, were gradually dissociated, and the calcium insensitive serum κ-casein was gradually associated with the micelles. The dissociated β-casein fraction was predominated by isoforms with lower number of phosphate groups. For micelles with increasing dephosphorylation, the molar mass decreased, the gyration and hydrodynamic radii decreased, the ratio of gyration to hydrodynamic radii and micellar hydration increased, the spherical morphology was generally retained, and the internal protein inhomogeneity disappeared progressively. These results suggest that after dephosphorylation, the caprine micelle framework underwent an intra-micellar mass redistribution, and become more loose and homogeneous. [Display omitted] • Caprine MCC incubated with phosphatase for 0–3 h reached 0–49% dephosphorylation. • β- and κ-Caseins were preferably dephosphorylated over α s -casein. • Micellar calcium and β-casein were dissociated with increasing dephosphorylation. • Dissociated β-casein was predominated by isoforms with less phosphate group. • M w decreased and R g /R h increased for micelles with increasing dephosphorylation. [ABSTRACT FROM AUTHOR]

In this work, the isothermal section at 900 °C, a liquidus projection and invariant reaction temperatures in the Mo–Ni–W ternary system were established using X-ray diffraction (XRD), Differential Scanning calorimeter (DSC) and electron probe micro-analysis (EPMA). Based on the experimental phase diagram data from the present work and the literature, the Mo–Ni–W system was assessed by means of the CALPHAD (CALculation of PHAse Diagrams) method. The liquid, fcc-(Ni), bcc-(Mo) and bcc-(W) phases were described with a regular solution model. The sub-lattice models were used to express Gibbs energies of the intermediate phases of MoNi 3 , MoNi, (Mo, W)Ni 4 , WNi and W 2 Ni. The present modeling covers the entire composition and an extensive temperature ranges of the Mo–Ni–W ternary system, and a set of self-consistent thermodynamic parameters were finally obtained. Comprehensive comparisons between the calculated and measured phase diagram data show that most experimental information is satisfactorily accounted for by the present thermodynamic description. Scheil solidification simulations for a few representative as-cast alloys were performed. It was found that the solidified microstructures can be reasonably described by the Scheil simulation. The liquidus projection and reaction scheme of the Mo–Ni–W system were generated by the presented modeling. [ABSTRACT FROM AUTHOR]

The Co–Ge binary system was reassessed by CALPHAD method in view of new phase diagram data and drawbacks of the previous modeling. A three-sublattice model (Co,Va) 1 (Co) 1 (Ge) 1 was used to describe the B8 2 -type βCo 5 Ge 3 -phase based on its crystal structure. In order to describe the transformation between ordered L 1 2 -type phase (Co 3 Ge) and the disordered fcc_A1 phase (αCo), one single Gibbs energy function was used for both ordered and disordered phases. In almost all the previous thermodynamic calculations, the ordered phase with a negligible homogeneity range, such as Co 3 Ge, is treated as a stoichiometric compound. Such a treatment is not physically sound. For (αCo) and (εCo), the magnetic contribution to Gibbs energy is taken into account. Both substitutional solution model and associated model were applied to describe the liquid phase, and thus two sets of self-consistent thermodynamic parameters for this system were obtained. It was found that the associated model can account for the experimental data more satisfactorily than the substitutional solution model, especially for the partial enthalpy of mixing data for the liquid phase. Five representative as-cast Co-Ge alloys were prepared to compare the solidified microstructure with that predicted according to thermodynamic calculations. According to the calculated Scheil solidification curves of two key alloys, the solidified microstructure for the alloys was analyzed. Also, the calculated amounts of the solidified phases in five as-cast alloys are compared with the experimental data resulting from automatic image analysis of the BSE images, showing a good agreement between the calculation and experiment, in particular for the case in which the associated model is used to describe the properties of the liquid phase. It is demonstrated that the combined use of the thermodynamic calculation and decisive experiment is an efficient strategy to obtain the desired microstructure. • Physical sound thermodynamic modeling for Co 3 Ge and βCo 5 Ge 3 phases is performed. • The associated model can describe enthalpy and phase diagram data simultaneously. • Invalidity of substitutional solution model for short-range ordering is analyzed. • Desired as-cast microstructure is obtained through thermodynamic calculations. [ABSTRACT FROM AUTHOR]

Abstract The influence of Cr 3 C 2 doping on the sintering process and mechanical properties of WC-Co cemented carbides was studied. Using differential thermal analysis of green powders and thermodynamic calculations, the disappearing temperature of solid-state binder phase in the ultra-fine WC-Co cemented carbides with different amounts of Cr 3 C 2 dopant was first investigated and then verified to descend with the increase of Cr content. Based on these investigations, the sintering temperatures of three alloys with 0.3, 0.5 and 0.65 wt% Cr were selected to high by 50 °C than the phase disappearing temperature of solid-state binder. Compared with the commercial sample with the sintering temperature at 1410 °C for Cr 3 C 2 doped WC-Co cemented carbides, the optimized sintering temperatures lead to finer microstructures and better mechanical properties, such as transverse rupture strength and hardness. In addition, the reliability for the performance of WC-Co cemented carbides prepared with the optimized sintering schedule is significantly improved in comparison with the commercial sample. The strategy from the present work can be used to design sintering process parameters during the manufacture of ultrafine WC-Co cemented carbides. Highlights • Thermodynamic calculations can establish a favorable sintering temperature range. • The optimized sintering temperature permitted better properties of cemented carbides. • The Weibull parameter can be improved by the optimized sintering temperature. [ABSTRACT FROM AUTHOR]

VC-Cr 3 C 2 is the most widely used grain growth inhibitor for ultrafine-grained cemented carbides. However, the mechanism for the high effectiveness of this inhibitor is still unclear. This work aims to clarify the inhibiting mechanism involving VC-Cr 3 C 2 inhibitor through investigations of a commercial ultrafine-grained WC–Co–VC–Cr 3 C 2 cemented carbide in an objective-aberration-corrected transmission electron microscope. Our results show that continuous segregation layers enveloping WC grains [(V,W,Cr)C x on (0001) WC basal facets and (Cr,W,V)C on {10 1 ̅ 0} WC prismatic facets] account for the high effectiveness of VC-Cr 3 C 2 inhibitor. Especially, the newly observed continuous and coherent (Cr,W,V)C layers on {10 1 ̅ 0} WC prismatic facets give an explanation for the superiority of VC-Cr 3 C 2 inhibitor compared with VC inhibitor. [ABSTRACT FROM AUTHOR]

Effect of molecule migration on the hardening of high-protein intermediate-moisture foods (HPIMF) in the early stage of storage was investigated through low-field NMR, texture analysis, confocal laser scanning microscopy, scanning electron microscopy, and protein solubility analysis. Model systems were made of water, glycerol and sorbitol, together with sodium caseinate (NaCN), soy protein isolate (SPI) or whey protein isolate (WPI), and stored at 25 °C to monitor molecular migration and the changes of texture, microstructure, and protein solubility. Both yield strain and yield stress of NaCN and SPI systems increased rapidly right after preparation, together with decreases in small molecules mobility and changes of microstructure, while WPI system showed more uniform structure without significant change of small molecules mobility. In addition, changes in protein solubility were observed in the SPI systems, but not in NaCN and WPI systems. These results suggested that the migration of small molecules (water, glycerol, and sorbitol) into protein particles during the early stage of storage could reduce the mobility of small molecules and might cause changes in microstructure, which could further cause hardening of HPIMF. In addition, the variation in protein sources was also a major factor contributing to the difference in texture properties. [ABSTRACT FROM AUTHOR]

Texture and microstructure of high-protein yoghurts manufactured from milk protein concentrate (MPC) fortified skim milk heated at different temperatures (75, 80, 85, 95 °C for 10 min) and pH (6.5, 6.7, 6.9, 7.1) were studied. Whey protein (WP) denaturation increased from 16% to 89% with increasing heating temperatures, while WP binding to casein micelles decreased from 95% to 21% with increasing heating pH. Gelation pH during fermentation increased with increasing heating temperatures and pH. Gel network became denser when heating temperatures and pH increased. Firmness and coagulum particle size of yoghurts increased with increasing heating temperatures and pH. Water-holding capacity reached above 87%, and increased slightly with increasing heating temperatures and pH, followed by slight decreases during storage. Reducing heating temperatures and pH of milk base offers potential strategies to obtain a desirably smooth texture without excessive syneresis for high-protein yoghurts manufactured by concentration before fermentation. [ABSTRACT FROM AUTHOR]

Abstract: Cemented carbides are hard and tough materials for cutting tool, consisting of micrometer-sized carbides embedded in a ductile metal binder phase. In order to increase the performance and extend the service lifetime of the cemented carbides, graded cemented carbides have been developed. The formation of gradient zone during liquid phase sintering is a diffusion-controlled process, and knowledge of diffusivity is indispensable to understand formation mechanism, optimize technological parameters and design a new type of graded cemented carbides. In this paper, a diffusion database for multi-component C–Co–Cr–W–Ta–Ti–Nb–N cemented carbides has been developed through a combination of experiment, theoretical analysis and assessment. The diffusion database contains the atomic mobility parameters for different diffusing elements in liquid and fcc phase. The atomic mobility parameters in liquid phase are theoretically calculated by the newly modified Sutherland equation, and the atomic mobility parameters in fcc phase are optimized by the diffusivities measured in the present work and from the literature. In conjunction with the thermodynamic database for cemented carbides (CSUTDCC1: Central South University Thermodynamic Database for Cemented Carbides—version-1), the diffusion database (CSUDDCC1: Central South University Diffusion Database for Cemented Carbides—version-1) can be used to simulate the gradient sintering process. Simulations of different kinds of graded cemented carbides are presented using the databases and compared where possible against experimental data, in order to validate its accuracy. [Copyright &y& Elsevier]