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The aim of this work was to enhance the mechanical and tribological properties of an alpha titanium substrate by forming a protective cermet coating on its surface. In this study, protective cermet coatings based on titanium borides were prepared by electric arc surfacing in a protective environment. Two types of protective environment were investigated during the surfacing process: (i) inert (argon) and (ii) reactive (nitrogen). The characteristic zones of the deposited layer were established depending on the environment used, and the coating-substrate transition zone was thoroughly examined. It was demonstrated that the formation of the transition zone results from the mutual diffusion of the molten material of the electrode material and the substrate. For the first time, the formation of TiB 2 -TiN eutectic in the form of whiskers 4–20 μm wide and 100–300 μm long distributed in the matrix of the Ti(B,N) x solid solution was established when forming a protective cermet coating in a nitrogen environment. The presence of this TiB 2 -TiN eutectic led to a significant increase in the hardness of the coating, up to 4.4 times, from 350 to 1530 HV. Tribological tests of surfacing coatings were conducted, and both 2D and 3D profiles of the wear grooves are presented, providing insight into the wear mechanism. It was found that the wear resistance of the cermet coating obtained in a nitrogen environment increased by 5.2 times, while in an argon environment it increased by 3.1 times as compared to the substrate without the protective cermet coating. The results indicate the potential of the developed protective cermet coatings for use in abrasive operating conditions. [ABSTRACT FROM AUTHOR]

Bulk metallic glasses formation is usually related to deep eutectic. They have unique properties which are different from crystalline alloys and get more and more attention, especially in the field of biomedical materials. This study attempts to develop general composition formulas to explain eutectic and relevant bulk metallic glasses, termed dual-cluster formulas model, written as C1[(principal cluster)1(glue atom)1 or 3] + C2[(principal cluster)2(glue atom)1 or 3]. Principal cluster is defined according to the close-packing efficiency and cluster separation, lever law is proposed to calculate the weight proportions C1 and C2, and the number of valence electrons e / u is examined for determining the glue atoms. Then the example of Ca-Mg system demonstrates the detailed procedures for establishing dual-cluster formulas model. Finally, eutectic and bulk metallic glasses of Ca(Zr,Ti,Mg,Fe)-based binary biomedical alloys are interpreted by dual-cluster formulas model. The work indicates that the compositions developed from dual-cluster formulas match the experimental results very well. Thus, a new practical method to quantitatively design bulk metallic glasses biomedical materials is proposed. [ABSTRACT FROM AUTHOR]

The microstructures and properties of foundry alloys designated by the generic term "cast irons" are highly diverse, even if we limit ourselves to so-called silicon cast irons, which are essentially quasi-eutectic Fe-C-Si alloys. This diversity is compounded by the fact that these microstructures appear partly during solidification and partly during solid-state transformations. Throughout the scientific career of Mats Hillert, his attention has been drawn to the wide range of phenomena involved in the formation of cast iron microstructures during solidification, as the present review of his contributions in this field shows. In addition, much of his work on the solid-state transformations of steels has found—or should find—an echo in the description of the matrix microstructure of graphitic cast irons, which is the subject of the final part of this article. [ABSTRACT FROM AUTHOR]

Morphology of eutectic in a hypoeutectic Cu-Zr alloy can be changed to various structures dependent on plastic deformation methods. This study reports morphological evolution of eutectic caused by unidirectional- and cross-rolling in a hypoeutectic Cu-2.7 at%Zr alloy. A graph-based method was applied to analyze the SEM images to characterize the morphological evolution of eutectics in terms of orientation, length, thickness, and connected structure of eutectics. Before rolling processes, an as-cast Cu-2.7 at%Zr alloy possessed a net-like morphology of eutectic with random orientations. The morphology of eutectic changed to the elongated and oriented one along the rolling direction by the unidirectional-rolling, and one along the two rolling directions by the cross-rolling. Variations of electrical conductivity by the unidirectionaland cross-rolling were also discussed based on the morphological evolution of eutectic. [ABSTRACT FROM AUTHOR]

The present work was the preliminary study of phase diagrams and miscibilities of low-temperature metallomesogen (MOM) model structures based on rod-like palladium (Pd) alkyl/alkoxy-azobenzene metal complexes and their mixtures with commercial liquid crystal materials for potential application. The initial results indicated the accessible temperature range and mesgenic miscibility between parent ligand, MOMs and commercial liquid crystal mixtures. The eutectic ligand/MOM composition with other MOMs and commercial nematic liquid crystal materials exhibited complete mesogenic miscibility and wide low-temperature mesogenic stability for eventual utilization in commercial liquid crystal devices. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths 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 interdisciplinary, conceptual article with implications in marketing financial products and services, we study real estate and capital markets characterized by a predatory paradigm and economic agents' dark financial profiles (DFPs). These are estimated by three orthogonal components—disconnection, irrationality, and deceit. We identify the best interactional patterns of borrower-lender profiles, ones that expectedly minimize the risk of default. We resort to discretized, predator–prey Lotka–Volterra equations where lenders act as predators and borrowers as prey, incorporating market trends and learning effects. To mathematically operationalize our framework, we use combinatorics with high, medium, and low levels of the three components of DFPs. We find 27 salient lender-borrower interactional scenarios and observe three different patterns: explosive, conducive, and implosive. Our theoretical findings indicate that equal (ir)rationality (in financial terms) between lenders and borrowers is a necessary but insufficient condition to maintain harmonious, long-term relationships. We use eutectic theory to map the agents' profiles by introducing another variable: Expected return [E(Rp)] versus risk [σ], using the Capital Asset Pricing Model (CAPM) as a base. We find six market segments: the inactive predators and prey, the loose, the greedy, the vulnerable, and the stable. We identify the optimal combination of borrowers–lenders interaction under risk, given market trends and learning effects. We propose a path for future research that would see the application of analytical tools such as factor analysis, k-means clustering algorithm, χ2 and non-parametric Kruskal–Wallis and Dunn's multiple comparison tests to verify differences among the hypothesized segments. [ABSTRACT FROM AUTHOR]

The macrokinetic characteristics of combustion of the quaternary Ti-Zr-B-C mixture as well as the mechanism and stages of phase formation for the synthesis products were investigated. The mechanical and thermophysical properties of the hot-pressed boride/carbide ceramics with eutectic composition (Ti,Zr)B 2 -43%at.(Zr,Ti)C were measured. Preliminary mechanical alloying (MA) of the (Zr + Ti) mixture was shown to yield Ti/Zr granules having a laminar structure and consisting of alternating layers of titanium, zirconium, and (Zr,Ti) ss solid solution. The method used to prepare reaction mixtures and the initial temperature T 0 increased within the range of 20–370 °C have virtually no effect on combustion temperature, which is 2260–2400 °C, while higher T 0 increases the combustion rate by a factor of 1.5–2. The use of MA Ti/Zr granules reduces the combustion rate as well as the specific heat release amount and the heat release rate. Time-resolved X-ray diffraction data showed that binary carbides (Zr 1-x Ti x)C and diborides (Ti 1-y Zr y)B 2 of variable stoichiometry are formed in the combustion wave of the Ti-Zr-B-C reaction mixtures within less than 0.25 s. The carbide and diboride phases are formed simultaneously; the use of MA Ti/Zr granules in the reaction mixtures reduces the content of solid solutions of variable stoichiometry among the reaction products. The ceramics fabricated using a combination of combustion synthesis and hot pressing have a dense and homogeneous structure that consist of bonded grains of the diboride (Ti 0.80 Zr 0.20)B 2 and carbide (Zr 0.83 Ti 0.17)C phases having the following properties: density, 5.3 g/cm3; hardness, 22.9 GPa; fracture toughness, 4.7 MPa m0.5; heat capacity, 0.52 J/(g·K); thermal diffusivity, 11.67 mm2/s; and thermal conductivity, 33.28 W/(m·K). [ABSTRACT FROM AUTHOR]

After reviewing and analysing literature data, the microstructure and phase composition of the Ti47.5Zr28Mn(22.5–х)V2Niх (where х = 5.0 and 17.5 at.%) eutectic alloys in the as-cast and annealed states as well as the phase composition of the hydrogenation products of these alloys are investigated using the x-ray phase analysis and scanning electron microscopy methods. As found, nickel is distributed in the alloy between the b.c.c. solid solution and the intermetallic compound with a significantly higher content in the latter. In addition, the phase composition of the initial alloy is changed with the substitution of Mn by 5.0–17.5 at.% of Ni: the ternary NiTiZr ψ-phase, which is isostructural to the Laves phase (C14), is formed. As shown, the size of the intermetallic crystallites is a critical factor for the activation of the H absorption at room temperature and a hydrogen pressure of 0.6 MPa. At a grain surface area of 1–10 µm2 in the initial eutectic microstructure, active interaction of the alloy with hydrogen at the first hydrogenation occurs exclusively during the heating and isobaric–isothermal exposure at 510±10 °C, whereas this process starts at room temperature, when the area of the crystallites is increased up to 100–300 µm2 after annealing. An increase in the size of each of the phase components cause greater volume misfits at the interphase boundaries between the adjacent crystallites at the initial stages of hydrogenation that leads to the cracking of the alloy surface and subsequent activation of interaction with hydrogen.

The calculation of the specifi c electrical conductivity of lithium and sodium fl uorides mixtures melts is presented. The Iinterest in the LiF–NaF system melts is determined by their practical signifi cance. Melts of LiF+NaF mixtures are used in heat-storing compositions and in metallurgy. They are part of various multicomponent systems. The specifi c electrical conductivity calculation by isoconcentration, isothermal and interpolation methods is given for LiF+NaF mixtures melts of various compositions using known reference data for the temperature range 1020...1340 K. A calculation has been performed for the eutectic composition. The resulting analytical equations have been used to describe and calculate the specifi c electrical conductivity of the eutectic mixture for temperatures 5°, 10°, 50°, 75°, 100° above the liquidus. The specifi c electrical conductivity of the eutectic mixture melt is calculated on isotherms by interpolation for the isoconcentration dependences of hypoeutectic and hypereutectic mixtures. Isotherms of electrical conductivity (1020...1340 K) of melts depending on the content of LiF and NaF components are described by a third-degree polynomial. Depending on the temperature, the coeffi cients in the resulting equation change linearly. A comparison has been made of the values of specifi c electrical conductivity ϰ(LiF+NaF), calculated from the obtained equations. The description of ϰ(LiF+NaF) by isoconcentration and isothermal methods has showed satisfactory convergence of calculation results and makes it possible to calculate the specifi c electrical conductivity of LiF+NaF mixtures melts of any given composition, including eutectic.

In light of the challenges posed by the low density, diminished energy levels, and shrinkage holes in the loading arise of the current cast-cured explosive liquid vehicle, TNT, the investigation of low-melting eutectic materials as potential substitutes for TNT has emerged as a focal point of research. By employing the solvent-nonsolvent method, the lowest eutectic mixture of TNBA(2,4,6-trinitro-3-bromoanisole)/MTNP(1-methyl-3,4,5-trinitropyrazole) was synthesized, distinguished by a moderate melting point and markedly elevated energy levels as compared to TNT. Comprehensive SEM, EDS, IR, XRD, and XPS analyses were conducted on the lowest eutectic mixture, substantiating the absence of any chemical interaction between TNBA and MTNP and affirming their exceptional compatibility. Moreover, an exploration into the thermal decomposition behavior and mechanism of the lowest eutectic mixture was undertaken, its mechanical sensitivity was tested, and its detonation performance was evaluated by EXPLO-5 software. The thermal decomposition parameters of the lowest eutectic mixture closely paralleled those of the precursor materials, with the thermal decomposition kinetics model function being identified as the Jander function. The impact sensitivity of the lowest eutectic was 48.1 cm and the friction sensitivity was 12%. Furthermore, the density of the lowest eutectic mixture surpassed 1.8 g/cm3, and its detonation velocity approached 8000 m/s, markedly surpassing the explosive performance of TNT.

The present work was the preliminary study of phase diagrams and miscibilities of low-temperature metallomesogen (MOM) model structures based on rod-like palladium (Pd) alkyl/alkoxy-azobenzene metal complexes and their mixtures with commercial liquid crystal materials for potential application. The initial results indicated the accessible temperature range and mesgenic miscibility between parent ligand, MOMs and commercial liquid crystal mixtures. The eutectic ligand/MOM composition with other MOMs and commercial nematic liquid crystal materials exhibited complete mesogenic miscibility and wide low-temperature mesogenic stability for eventual utilization in commercial liquid crystal devices.

Thermoelectric (TE) materials are known for efficiently converting thermal to electrical energy, and vice versa. Multiphase TEs offer better freedom to tune the TE properties of such materials by varying individual phase fractions, microstructural morphology, interface density controls, etc. These controlled changes in microstructural features can be achieved by directional solidification. Bi2Te3-Ga2Te3 based TEs have been reported with enhanced TE performance. In the present study, alloys with a combination of these phases were developed using a eutectic composition from the pseudo-binary phase diagram of Bi2Te3–Ga2Te3. The alloys were fabricated using the vertical Bridgman method with three different solidification velocities (V), namely 1000 (E1), 200 (E2) and 10 (E3) μ m s−1, at a constant temperature gradient of 35 K cm−1 at the solid/liquid interface. Microstructural features show a significant change in the morphology and the interlamellar spacing between two adjacent Ga2Te3 lamellae in alloys E1, E2 and E3. In addition, x-ray diffraction patterns suggest changes in the lattice parameters of Bi2Te3 and Ga2Te3 for all alloys. Significant change in the macrotexture of the different alloys was observed along the growth direction. The highest power factor of 1.6 mW mK−2 was recorded for alloy E2 at room temperature. Alloy E2 shows the highest figure of merit among all the alloys investigated (0.38 at room temperature), attributed to the highest S value of 201.7 μ V K−1 at room temperature. In addition, the total thermal conductivity of all alloys was around 1.33 W mK−1 at 307 K, while alloy E1 has the smallest lattice and bipolar thermal conductivity. [ABSTRACT FROM AUTHOR]

Mg- x Ca (x = 3, 7, 11, 14, wt.%) binary hypoeutectic alloys are successfully synthesized via solidification in the present work. The microstructure, phase compositions and hydrogen generation characteristics of as-cast Mg–Ca alloys and ball milled Mg–Ca composites with TiC and Ni addition have been investigated in this work for a new hydrogen supply source application. A lamellar structure with alternately distributed Mg and Mg 2 Ca is formed in the eutectic regions of as-cast Mg–Ca binary alloys. It is found that as-cast Mg–Ca binary alloys show extremely sluggish hydrolysis kinetics and low hydrogen yield in both tap water and simulated seawater. Mg 2 Ca phase preferentially reacts with water during hydrolysis process in simulated seawater. Many cracks arise with hydrolysis reaction, meanwhile, the cracks further assist in the hydrolysis of the internal matrix via assisting water solution transfer. After ball milling with TiC and Ni of Mg–Ca binary alloys, the hydrolysis performance is substantially modified. Mg–14Ca-3wt.%TiC-5wt.%Ni composite generates 836.6 mL g−1 of hydrogen within initial 95 min. The conversion rate of Mg–14Ca-3wt.%TiC-5wt.%Ni composite in simulated seawater is as high as 99.4%, indicating a thorough hydrolysis of Mg and Mg 2 Ca phases with the catalysis of TiC and Ni. This work shows that microstructure refinement, catalysis, Mg(OH) 2 exfoliation and water solution transfer account for the complete hydrolysis. • Mg–Ca alloys with lamellar structures for hydrogen generation are successfully prepared. • Mg 2 Ca phase preferentially reacts with water than Mg during hydrolysis process. • TiC and Ni show superior catalysis on hydrolysis of Mg and Mg 2 Ca phases. • Mg–14Ca-3wt.%TiC-5wt.%Ni composite can achieve complete hydrolysis in simulated seawater. [ABSTRACT FROM AUTHOR]

After reviewing and analysing literature data, the microstructure and phase composition of the Ti47.5Zr28Mn(22.5 – х)V2Niх (where х = 5.0 and 17.5 at.%) eutectic alloys in the as-cast and annealed states as well as the phase composition of the hydrogenation products of these alloys are investigated using the x-ray phase analysis and scanning electron microscopy methods. As found, nickel is distributed in the alloy between the b.c.c. solid solution and the intermetallic compound with a significantly higher content in the latter. In addition, the phase composition of the initial alloy is changed with the substitution of Mn by 5.0–17.5 at.% of Ni: the ternary NiTiZr ψ-phase, which is isostructural to the Laves phase (С14), is formed. As shown, the size of the intermetallic crystallites is a critical factor for the activation of the H absorption at room temperature and a hydrogen pressure of 0.6 MPa. At a grain surface area of 1–10 µm2 in the initial eutectic microstructure, active interaction of the alloy with hydrogen at the first hydrogenation occurs exclusively during the heating and isobaric–isothermal exposure at 510 ± 10 °C, whereas this process starts at room temperature, when the area of the crystallites is increased up to 100–300 µm² after annealing. An increase in the size of each of the phase components cause greater volume misfits at the interphase boundaries between the adjacent crystallites at the initial stages of hydrogenation that leads to the cracking of the alloy surface and subsequent activation of interaction with hydrogen. [ABSTRACT FROM AUTHOR]

Glass formation and the nature of the chemical interaction in the As2Se3–Tl2Te3 system were studied by differential-thermal (DTA), X-ray phase (XRD), microstructural (MSA) analysis. Based on the performed experiments T-x phase diagram is constructed. It is established that the phase diagram of the system is a partially quasi-binary section of the quaternary system Tl,As//Se,Te. Eutectic equilibrium and peritectic transformation process occur in the system. When the ratio of As2Se3 and Tl2Te3 components is 1:1, a new quaternary compound Tl2As2Se3Te3 is formed. It has been established that the Tl2As2Se3Te3 compound melts with an open maximum at 568 K and crystallizes in a hexagonal symmetry. In the system, under normal cooling, the glass formation area reaches −80 mol.% Tl2Te3, and in the mode of quenching in liquid nitrogen up to −100 mol.% T12Te3. The photoelectric properties of glassy alloys (As2Se 3 ) 1 − x (Tl2Te 3 ) x (x = 0. 0 1 ; 0.3; 0.05) have been studied. Depending on the Tl2Te3 concentration of the system, the observed changes in the photoelectric properties and calculated parameters are presented. [ABSTRACT FROM AUTHOR]

The change in the structure and hardness of the Fe–Ni–Ti–C–B system composite, obtained by the method of self-propagating high-temperature synthesis (SHS), after hot plastic deformation under uniaxial compression conditions is studied. The matrix of the composite is a solid solution of Ni and Ti in a γ‑Fe crystal lattice, and the strengthening phases are TiC, TiB2, Fe2B, Ni3Ti, and NiTi. It is shown that during uniaxial compression upon heating, recrystallization processes occur in the metal matrix of the composite, which facilitates further deformation. It is found that, after compression at a temperature of 910°C and a pressure of 300 MPa, the true deformation of the composite is 0.37. In this case, in the central part of the sample in the region of compressive stresses, the ratio of deformed and recrystallized grains is approximately the same. On the lateral surface of the samples, in the zone of action of tensile stresses, microcracks with a depth of less than 0.2 mm appear in zones of the eutectic γ + Fe2B structure. [ABSTRACT FROM AUTHOR]

The phase composition of the Al–Cu–Ca–Mn alloys containing (wt %) 6% Cu, 2% Mn, and to 4% Ca is analyzed. The Al–Cu–Ca–Mn phase diagram in the Al corner is proposed, according to which five four-phase regions with the participation of Al-based solid solution (Al) and various intermetallic compounds are possible to exist in the solid state. The Al–6% Cu–1% Ca–2% Mn composition is suggested as the base for developing new-generation heat-resistant (hot-strength) alloys. In the case of such contents of alloying elements, the combination of aluminum matrix containing Al20Cu2Mn3 dispersoids and (Al) + Al27Ca3Cu7 eutectic characterized by fine structure is possible. [ABSTRACT FROM AUTHOR]

Cryoablation has become a valuable treatment modality for the management of liver cancer. However, one of the major challenges in cryosurgery is the incomplete cryodestruction near the edge of the iceball. This issue can be addressed by optimizing cryoablation parameters and administering thermotropic drugs prior to the procedure. These drugs help enhance tumor response, thereby strengthening the destruction of the incomplete frozen zone in liver cance. In the present study, the feasibility and effectiveness of a thermophysical agent, KCl solution, were investigated to enhance the cryodestruction of HepG2 human liver cancer cells. All cryoablation parameters were simultaneously optimized in order to significantly improve the effect of cryoablation, resulting in an increase in the lethal temperature from − 25 °C to − 17 °C. Subsequently, it was found that the application of KCl solution prior to freezing significantly decreased cell viability post-thaw compared to cryoablation treatment alone. This effect was attributed to the eutectic effect of KCl solution. Importantly, it was found that the combination of KCl solution and freezing was less effective when applied to LO2 human liver normal cells. The data revealed that the ratio of mRNA levels of Bcl-2 and bax decreased significantly more in HepG2 cells than in LO2 cells when cryoablation was used with KCl solution. In conclusion, the results of this study demonstrate the effectiveness of KCl solution in promoting cryoablation and describe a novel therapeutic model for the treatment of liver cancer that may distinguish between cancer and normal cells. [ABSTRACT FROM AUTHOR]

This research investigates the microstructural evolution and mechanical properties of LM25 (Al-Si-Mg) alloy and Cr-modified LM25-Cr (Al-Si-Mg-Cr) alloy. Microstructural analysis reveals distinctive ε-Si phase morphologies, with Cr addition refining dendritic structures and reducing secondary dendrite arm spacing in the as-cast condition. Cr modification results in smaller-sized grains and a modified ε-Si phase, enhancing nucleation sites and reducing ε-Si size. Microhardness studies demonstrate significant increases in hardness for both alloys after solutionising and aging treatments. Cr-enriched alloy exhibits superior hardness due to solid solution strengthening, and prolonged aging further influences ε-Si particle size and distribution. The concurrent rise in microhardness, attributed to refined dendritic structures and unique ε-Si morphology, underscores the crucial role of Cr modification in tailoring the mechanical properties of aluminium alloys for specific applications.

Phase and structural transformations in multilayer Ti/Cu foils of eutectic Composition I (Ti50‒Cu50 wt.%) and Composition II (Ti22‒Cu78 wt.%), obtained by layer-by-layer electron beam physical vapor deposition of components in vacuum, were investigated using differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM) methods. It was found that during heating of multilayer foils in the temperature range of 400…600 °C, due to the diffusion interaction between Ti and Cu layers, the following intermetallic compounds are formed: Cu4 Ti, Cu4 Ti3, CuTi, and CuTi2 in Composition I foils, and Cu4 Ti and Cu4 Ti3 in Composition II foils. Upon further heating, melting of the multilayer foils of both eutectic compositions occurs. The Composition II multilayer foils begin to melt at a temperature of 879 °C, close to the equilibrium melting temperature of the eutectic alloy of the same composition (875 °C), while in the case of Composition I multilayer foils, the onset of melting occurs at a temperature of 915 °C, which is lower compared to the melting temperature of the eutectic alloy of Composition I (960 °C). Considering that Cu4 Ti and Cu4 Ti3 metastable phases are formed in Composition I multilayer foils, which are components of the more fusible eutectic of Composition II, the reduction in the melting temperature of the foils may be due to their metastable structure. Such behavior of multilayer Ti/Cu foil of eutectic Composition I may facilitate softening of the temperature conditions required to establish physical contact in the material bonding zone during their reactive brazing. [ABSTRACT FROM AUTHOR]

A YSZ-Al reactive system was used as raw materials for the fabrication of a novel YSZ-Al 2 O 3 composite coating by plasma spraying. Thermite reaction was triggered in the plasma jet and phases like alumina and Zr–Al intermetallics were in-situ formed in the reaction zone. Solid solution reaction occurred in the rapid solidification of the homogeneously mixed Y–Al–Zr–O superheated melt and high solubility of Al3+ was also observed in the supersaturated solid solution. Phase transitions from the reactive precursor to the coating composition and the microstructure formation of the coating lamellae were revealed by extensive characterizations including XRD, XPS, Raman, SEM, EDS, and EPMA. Good compatibility within the coating compositions and compact interlamellar bonding were obtained in the as-prepared YSZ-Al 2 O 3 composite coating. The coating's surface and cross-section Vickers hardness values were 7.48 GPa and 10.40 GPa, respectively. Additionally, the micro-zone hardness value of the eutectic area could reach 19.43 GPa. [ABSTRACT FROM AUTHOR]

[Display omitted] Eutectic growth process is usually characterized by the simultaneous coupled growth of two different solids within one uniform liquid phase, while fluid dynamics normally predicts the equiaxed shrinkage for floating viscous droplets on freezing. Here a decoupling effect was induced by the microgravity and containerless states aboard space station, which led to the independent dendrite growth of two eutectic phases within extremely undercooled liquid Nb-Si refractory alloy. The confronting fluid flow pattern driven by polar heterogeneous nucleation was found to stimulate the elongated surface deformation of alloy droplet at a high dendrite growth velocity. [ABSTRACT FROM AUTHOR]

General interest in the deployment of molten salt reactors (MSRs) is growing, while the available data on uranium-containing fuel salt candidates remains scarce. Thermophysical data are one of the key parameters for reactor design and understanding reactor operability. Hence, filling in the gap of the missing data is crucial to allow for the advancement of MSRs. This study provides novel data for two eutectic compositions within the NaF-KF-UF4 ternary system which serve as potential fuel candidates for MSRs. Experimental measurements include their melting point, density, fusion enthalpy, and vapor pressure. Additionally, their boiling point was extrapolated from the vapor pressure data, which were, at the same time, used to determine the enthalpy of vaporization. The obtained thermodynamic values were compared with available data from the literature but also with results from thermochemical equilibrium calculations using the JRCMSD database, finding a good correlation, which thus contributed to database validation. Preliminary thoughts on fluoride salt reactor operability based on the obtained results are discussed in this study. [ABSTRACT FROM AUTHOR]

Objective: To assess the clinical response of EMLA cream (Eutectic Mixture of Local Anaesthetics; 2.5% Lidocaine/2.5% Prilocaine) in decreasing peripheral cannulation pain in children. Study Design: Quasi-experimental study. Place and Duration of Study: Combined Military Hospital, Rawalpindi Pakistan, from May to Aug 2021. Methodology: This study was conducted on 80 paediatric patients who were classified as American Society of Anesthesiologists (ASA) Grades I and I and selected using non-probability consecutive sample. They underwent peripheral cannulation to maintain intravascular access for surgical procedure. The forty children in EMLA Group (Group-A) were applied 2.5 ml EMLA cream for 60 min, covered by Tegaderm® over suitable vein, while the 40 children in Control Group (Group-B) received no local anesthetic cream. Participants rated pain during venipuncture on Visual Analog Scale (VAS 0-10; 0, no pain; 10, intolerable pain). Results: Out of 80 patients equaly divided into two groups, 40(50%) were males, while 40(50%) were females. The patients included in our study had mean age of 7.35±1.5 years. In EMLA group the mean score of pain was 1.5±0.87 compared to the Control group (mean score = 7.4±1.4; p=0.001). Conclusion: The result of our study suggests that EMLA cream is more efficacious in decreasing venipuncture pain than if no local anaesthetic cream is applied. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology 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.)

As part of the development of critical technologies, it is necessary to search for alternative replacement of components in the compositions of aluminum ligatures, including known modifying additives of scandium and yttrium with other rare-earth and rare elements. Aluminum ligatures with rare-earth metals are widely considered in many scientific papers, but the research on the production of Al-Yb ligatures is limited. In this paper, the authors describe the results of studying the production of ligatures of the aluminum-ytterbium system from ytterbium oxide by aluminothermic reduction, containing nanoscale Al3Yb intermetallic compounds and eutectics in their structure. Serving as crystallization centers, the optimal-size particles of intermetallic compounds provide uniform fine-grained structure in aluminum alloy castings. The relationship has been obtained that enables the maximum transition of ytterbium into the alloy depending on the quantitative and qualitative composition of the reaction mixture and various melting process parameters. The conducted studies have shown that ligatures obtained by aluminothermic reduction of ytterbium oxide with the addition of 5 to 15 wt. % Mg to the reaction mixture have the highest characteristic of ytterbium transition into the ligature. [ABSTRACT FROM AUTHOR]

With the emergence of new applications for low-melting-point solder alloys, such as self-healing and semisolid additive manufacturing, understanding their long-term microstructural stability has become necessary. Sn-Bi-In alloys provide an attractive option for such applications, with a melting point below 150°C; however, little is known about their long-term stability and microstructural evolution. In this research, we conducted extended stability experiments for Sn-40Bi and Sn-40Bi-10In alloy compositions over three different heat-treatment periods of 12 h, 168 h, and 360 h. The microstructure of the two alloys prominently featured Sn-rich globules, which were observed to be finer in the Sn-40Bi-10In alloy than in the Sn-40Bi composition. The finer globules in Sn-40Bi-10In may be attributed to initial Sn-rich islands, which facilitated improved globule refinement during the semisolid stage. Furthermore, both the size and fraction of the globules were found to increase with increasing heat treatment time in Sn-Bi-In alloy; it was also observed that the Sn-40Bi-10In alloy globules exhibited a gradual rise in overall Bi content with time, whereas the interglobular Sn/Bi/BiIn eutectic regions showed a decrease in Bi content and an increase in Sn content. [ABSTRACT FROM AUTHOR]

In the TlАs2Se4-CuCr2Te4 system, samples were synthesized in a wide range and studied by methods of physical and chemical analysis: differential thermal analysis (DTA), X-ray diffraction analysis (XRD), microstructural analysis (MSA), as well as determination of density and microhardness and its was constructed T-x phase diagram. It has been established that the phase diagram of the TlАs 2Se4-CuCr2Te4 system is quasi-binary and eutectic. The composition of the eutectic formed between the compounds ТlАs2Se4 and CuCr2Te4 is 10 mol % CuCr2Te4, temperature 498 K. At room temperature, solid solutions based on TlAs2Se4 in the system reach 3 mol. % CuCr2Te4, and based on CuCr2Te4 - 7 mol % TlAs2Ce4. Under normal conditions, the glass transition region based on CuCr2Te4 extends to 12 mol % TlAs2Se4. [ABSTRACT FROM AUTHOR]

A critical review of the literature on the methods of concentration and extraction of biobutyric acid from fermentation solutions has been carried out. The best results of these processes are achieved by combining extraction with salting. It is proposed to use polyethylene glycols with diff erent molecular weights as non-fl ammable and environmentally friendly extractants. The purpose of the study was to identify the phase behavior of mixtures of components, study solubility and construct a phase diagram of the previously unexplored double system butyric acid – PEG-1500 in the range −10.0–50.0°C. The transition temperatures of phase states in mixtures of components of the dual system butyric acid (BA) – polyethylene glycol-1500 (PEG-1500) in the temperature range −10–50°C have been found by the visual-polythermal method. The phase diagram above the eutectic line shows a large crystallization fi eld of PEG-1500, while the crystallization fi eld of BA has very small dimensions. It has been established for the fi rst time that eutectic equilibrium is carried out in the system at −6.6°C, the solid phases of which are crystals of BA and PEG-1500, the composition of the liquid phase of eutectic (3.20 wt.% BA) has been determined. A method for concentrating BA and separating the components of the investigated system based on the crystallization of PEG-1500 during cooling of mixtures is proposed.

The effect of a minor amount of rare-earth element Nd addition (0.1 at%) on the microstructural properties, microhardness, and cyclic oxidation resistance of NiAl–Cr(Mo) alloy is investigated in detail. The microstructure of investigated alloys is composed of NiAl-based dendrites and a eutectic mixture whose components are NiAl and Cr(Mo) phases. The minor amount of Nd addition refines the microstructure and increases the microhardness considerably. The results of the cyclic oxidation tests reveal that the surface scales of both alloys are mainly consisted of α-Al2O3 and little amount of Cr2O3. A Cr(Mo)-rich layer is observed in the metal/oxide interface. With Nd addition, the oxidation resistance of Ni–33Al–31Cr–3Mo alloy is strongly improved. The Nd-added alloy exhibits lower oxidation mass gain and increased scale adherence. [ABSTRACT FROM AUTHOR]

While there have been numerous studies on the use of manganese acetate for electrode manufacture, scarce reports exist on the utility of manganese acetate electrolytes for energy storage applications. This study provides a comprehensive understanding of the thermal, volumetric, and transport properties of manganese acetate hydrate solutions and highlights their potential for use in energy storage applications. Noteworthy thermal behaviours, phase transitions, and strong interactions between manganese cations, acetate anions, and water molecules are observed. Transport properties reveal salt concentration's impact (0.4–3.9 mol L−1) on viscosity and conductivity, with higher concentrations (>2.5 mol L−1) indicating increased interaction. The non‐Arrhenius behaviour in conductivity is elucidated using the Vogel‐Fulcher‐Tammann model, accentuating the unique properties of these solutions compared to other aqueous electrolytes due to the role of acetate ligands. The formulated two‐electrode symmetric supercapacitors exhibit pseudocapacitive behaviour, reversible redox reactions (Mn2+/Mn3+), and salt concentration‐dependent specific capacitance. Manganese acetate as an electrolyte leads to reversible manganese dioxide deposition, with its concentration affecting redox reactions and capacitance. Molecular simulations support the observed electrochemical performance, emphasizing the Mn2+‐acetate complexation. Long‐term cycling experiments demonstrate stability over 2000 cycles, with a stable specific capacitance of 130 F g−1 and a gradual coulombic efficiency decrease (~97 %). The results of this work underscore the potential of manganese acetate hydrate solutions as a stable, effective and green electrolyte for energy storage applications. [ABSTRACT FROM AUTHOR]

Using DTA, XRF, MSA methods, as well as by measuring microhardness and determining density, composite materials in the TlSe-CuCr2Te4 system were synthesized and a T-x phase diagram was constructed. It has been established that the TlSe-CuCr2Te4 system is a quasi-binary section of the quasi-ternary TlSe-CuTe-Cr2Te3 system. Solid solutions based on TlSe at room temperature reach up to 3 mol % CuCr2Te4, and based on CuCr2Te4 solid solutions up to -12 mol % TlSe. The joint crystallization of TlSe and CuCr2Te4 compounds ends with a double eutectic of composition 20 mol % CuCr2Te4 and temperature 240°C. [ABSTRACT FROM AUTHOR]

This research investigates the microstructural evolution and mechanical properties of LM25 (Al-Si-Mg) alloy and Cr-modified LM25-Cr (Al-Si-Mg-Cr) alloy. Microstructural analysis reveals distinctive ε-Si phase morphologies, with Cr addition refining dendritic structures and reducing secondary dendrite arm spacing in the as-cast condition. Cr modification results in smaller-sized grains and a modified ε-Si phase, enhancing nucleation sites and reducing ε-Si size. Microhardness studies demonstrate significant increases in hardness for both alloys after solutionising and aging treatments. Cr-enriched alloy exhibits superior hardness due to solid solution strengthening, and prolonged aging further influences ε-Si particle size and distribution. The concurrent rise in microhardness, attributed to refined dendritic structures and unique ε-Si morphology, underscores the crucial role of Cr modification in tailoring the mechanical properties of aluminium alloys for specific applications. [ABSTRACT FROM AUTHOR]

Phase equilibria in CaCl2–CaCl2⋅4CO(NH2)2–H2O system sections are studied at temperatures from 0 to –55°C. The earlier hypothesis that the formation of a low-temperature eutectic (–55°C) in the system is caused by CaCl2⋅4CO(NH2)2 is confirmed. A number of low-temperature eutectic mixtures promising for the development of anti-icing reagents on their basis are revealed. [ABSTRACT FROM AUTHOR]

Thermochemical energy storage using salt hydrates is a promising method for the efficient use of energy. In this study, three host matrices, expanded vermiculite, expanded clay, and expanded natural graphite were impregnated with a eutectic mixture of CaCl2·6H2O and bischofite (MgCl2·6H2O). These composites were subjected to various humidity conditions (30–70% relative humidity) at 20 °C over an extended hydration period to investigate their cyclability. It was shown that only expanded natural graphite could contain the deliquescent salt at high humidity over 50 cycles. Hence, the expanded natural graphite composites containing either CaCl2·6H2O or CaCl2·6H2O/bischofite eutectic mixture were placed in a lab-scale open packed bed reactor, providing energy densities of 150 and 120 kWh/m3 over 20 h, respectively. The eutectic composite showed slightly lower temperature lift, water uptake rate, and power output but at reduced cost. Using the eutectic mixture also decreased the composite's dehydration temperature at which the maximum mass loss rate occurred around 16.2 °C to 62.3 °C, allowing recharge using less energy-intensive heating methods. The cost of storing 1 kWh of energy with expanded natural graphite composites is only USD 0.08 due to its stability. This research leveraging cost-effective composites with enhanced stability, reaction kinetics, and high thermal energy storage capabilities benefits renewable energy, power generation, and the building construction research communities and industries by providing a competitive alternative to sensible heat storage technologies. [ABSTRACT FROM AUTHOR]

The thermal characterization of two binary systems of n-alkanes that can be used as Phase Change Materials (PCMs) for thermal energy storage at low temperatures is reported in this work. The construction of the solid–liquid binary phase diagrams was achieved using differential scanning calorimetry (DSC) and Raman spectroscopy. The solidus and liquidus equilibrium temperatures were determined using DSC for thirty-nine different samples, three for the pure n-alkanes and the remaining for binary mixtures at selected molar compositions and used to acquire the corresponding solid–liquid phase diagrams. The two binary systems of n-octane/n-decane (C8/C10) and n-decane/n-dodecane (C10/C12) are characterized by a eutectic behavior at low temperatures. The eutectic temperature for the system C8/C10 was found at 211.95 K and the eutectic composition appeared at the molar fraction xoctane = 0.87. For the system C10/C12, the eutectic temperature was found at 237.85 K, and the eutectic composition appeared for the molar fraction xdecane = 0.78. This work aims to fulfill the lack of available data in the existing literature, considering the potential application of these systems for low-temperature thermal energy storage. Raman spectroscopy was used to complement the DSC data for the construction of the solid–liquid phase equilibrium diagrams, enabling the identification of the solid and liquid phases of the system. Additionally, the liquidus curve of the phase diagram was successfully described using a modified freezing point depression curve as fitting equation, the absolute root mean square deviation for the data correlation of the C8/C10 and C10/C12 systems being 2.56 K and 1.22 K, respectively. Ultimately, the fitting procedure also enabled a good prediction of the eutectic point for both studied systems. [ABSTRACT FROM AUTHOR]

Wires of a Cu--3.8 wt% Zr alloy were produced by conform extrusion followed by wire drawing up to 0.2mm in diameter (S wire), or by conform extrusion and subsequent annealing during wire drawing up to 0.2mm (IA wire). The effects of microstructure on the strength and electrical conductivity of the S and IA wires were investigated. The severely drawn S and IA wires had a mixed microstructure consisting of a Cu parent phase with fine grains, fibrous eutectics elongated along the drawing direction, and granular eutectics. The 0.2% proof stress (·0.2) and tensile strength (·u) of the S and IA wires increased monotonically with increasing drawing ratio (©). The S wire with © = 7.8 exhibited large values of ·0.2 = 1080MPa and ·u = 1320 MPa. The S and IA wires having the mixed microstructure are strengthened primarily by high density of dislocations and grain refinement in the Cu phase and by the presence of fibrous and granular eutectics. The electrical conductivity (E) of the S wire increased in the early stage of wire drawing and then began to decrease, dropping to 42% IACS at © = 7.8. The increase in E is caused by refining of the eutectics, which was formed during casting, toward the granular or fibrous form. The E value of the IA wire after annealing was high, 72%IACS, and then decreased as © increased. Values of E of the S and IA wires with the mixed microstructure was estimated by applying rules of mixtures. The estimated values of E are in agreement with the measured values of E. It is shown that the presence of the fibrous and granular eutectics significantly increases the electrical conductivity. [ABSTRACT FROM AUTHOR]

The 3He gas is commonly used for the detection of thermal neutrons. However, with the depletion of 3He gas, there is a need to develop new solid scintillators for thermal neutron detection. Solid scintillators containing 6Li, which have large neutron capture cross-sections and a large amount of energy released by transmutation reactions, are commonly used as alternative candidates. However, only single-crystal scintillators are currently used, and their 6Li concentration is limited by their chemical composition. In this study, we designed, grew, and evaluated a new eutectic scintillator, Rb2CeCl5/LiCl, which can improve the 6Li concentration compared with single-crystal scintillators. Rb2CeCl5, which was selected as the scintillator phase, has excellent scintillator properties (light yield: 36,000 photons/MeV, decay time: mostly 24 ns, slightly 153 ns), and is less deliquescent than other halide scintillators. The crystal grown using the vertical Bridgman method exhibited a eutectic phase composed of Rb2CeCl5 and LiCl. The eutectic crystals exhibited Ce3+ 5d-4f emissions, with a peak between 360 and 370 nm. The Rb2CeCl5 phase was identified as the luminescent phase via cathodoluminescence mapping, and 16,000 photons/neutron of the light yield and 56.1 ns of the decay time were observed. This study indicates that the Rb2CeCl5/LiCl eutectic scintillator is a promising candidate for use in thermal neutron detectors. [ABSTRACT FROM AUTHOR]

We present a comprehensive study on the identification of eutectic high entropy alloys (EHEAs) through integration of CALculation of PHAse Diagrams (CALPHAD), machine learning (ML), and experimental data. By performing high-throughput CALPHAD calculations to obtain the temperature differences between liquidus and solidus phases (ΔT) and employing gradient descent optimization to identify local minima in ΔT surface, we obtained a reliable dataset for EHEAs across 5–6 component alloy families, which effectively addresses current limitations in both the quality and availability of EHEA data. In conjunction with literature-based experimental data, this dataset serves as the foundation for ML models trained with an XGBoost classifier. The physical descriptors with the most significant effects on the classification of eutectics and non-eutectics are identified. Our study reveals that configurational entropy alone yields a remarkable 98% classification accuracy, elucidating its dual role in phase stabilization and melting point depression. For the first time, an explicit phase selection rule to identify eutectics has been derived from an artificial neural network model, which facilitates efficiently screening EHEAs without resorting to CALPHAD nor ML models. This study presents a robust, data-driven strategy applicable not only to EHEAs but also to a broader range of alloy systems.