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Quantum memories facilitate the storage and retrieval of quantum information for on-chip and long-distance quantum communications. Thus, they play a critical role in quantum information processing and have diverse applications ranging from aerospace to medical imaging fields. Bulk acoustic wave (BAW) phonons are attractive candidates for quantum memories because of their long lifetimes and high operating frequencies. In this study, we establish a modeling approach to design hybrid magnonic high-overtone bulk acoustic wave resonator (HBAR) structures for high-density, long-lasting quantum memories, and efficient quantum transduction devices. We illustrate the approach by investigating a hybrid magnonic system, consisting of a gadolinium iron garnet (GGG) thick film and a patterned yttrium iron garnet (YIG) thin film. The BAW phonons are excited in GGG thick film via coupling with magnons in the YIG thin film. We present theoretical and numerical analyses of the diffraction-limited BAW phonon lifetimes, modeshapes, and magnon–phonon coupling strengths in YIG/GGG planar and confocal HBAR (CHBAR) structures. We utilize Fourier beam propagation and Hankel transform eigenvalue problem methods and compare the two methods. We discuss strategies to improve the phonon lifetimes in the diffraction-limited regime, since increased lifetimes have direct implications on the storage times of quantum states for quantum memory applications. We find that ultra-high cooperativities and phonon lifetimes on the order of ∼ 10 5 and ∼ 10 milliseconds, respectively, could be achieved using a CHBAR structure with 10 μ m YIG lateral area. Additionally, high integration density of on-chip memory or transduction centers is naturally desired for high-density memory or transduction devices. The proposed CHBAR structure will offer more than 100-fold improvement of integration density relative to a recently demonstrated YIG/GGG device. Our results will have direct applicability for devices operating in the cryogenic or milliKelvin regimes. For example, our study will inform the design of HBAR devices that could couple with superconducting qubits for promising quantum information platforms. [ABSTRACT FROM AUTHOR]

We examined the sweat characteristics and fluid balance of elite female field hockey players during two heat training camps. Fourteen elite female field hockey players from the Australian national squad participated in two heat training camps held ∼6 months apart, following winter- (Camp 1) and summer-based training (Camp 2). Daily waking body mass (BM) and urine specific gravity (USG) were collected, along with several markers of sweat and fluid balance across two matches per camp. There was a 19% mean reduction in estimated whole-body sweat sodium concentration from Camp 1 (45.8 ± 6.5 mmol/L) to Camp 2 (37.0 ± 5.0 mmol/L; p <.001). Waking urine specific gravity ≥ 1.020 was observed in 31% of samples, with no significant differences in mean urine specific gravity or BM between camps (p >.05), but with substantial interindividual variation. Intramatch sweat rates were high (1.2–1.8 L/hr), with greater BM losses in Camp 1 (p =.030), resulting in fewer players losing ≥2% BM in Camp 2 (0%–8%), as compared with Camp 1 (36%–43%; p =.017). Our field data suggest that elite female field hockey players experience substantial sweat losses during competition in the heat regardless of the season. In agreement with previous findings, we observed substantial interindividual variation in sweat and hydration indices, supporting the use of individualized athlete hydration strategies. [ABSTRACT FROM AUTHOR]

Investigating thermal convection within porous media permeated by fluids and micro-organisms stands as a significant inquiry with broad relevance across geophysical and engineering domains. Studying convection within porous media can aid in controlling temperature and nutrient distribution for cell growth and tissue regeneration, as well as the efficiency of biofuel fermentation and production processes. Hence, the primary objective of this study is to investigate the influence of time-periodic gravitational forces on Darcy–Brinkman bio-thermal convection within a porous medium layer. This medium is saturated with a Newtonian fluid that encompasses gyrotactic micro-organisms. The gravity modulation amplitude is assumed to be very small. A weak nonlinear stability analysis is performed to analyze the stationary mode of bioconvection. The heat transport, measured by the Nusselt number, is governed by a non-autonomous Ginzburg–Landau equation. The research explores the influence of several parameters on heat transport, including the Vadaszs number, the modified bioconvective Rayleigh–Darcy number, cell eccentricity, modulation frequency, and modulation amplitude. The results are presented graphically, illustrating the impact of these parameters on heat transfer. The findings reveal that both the Vadaszs number and the modulation amplitude have a positive effect on heat transfer, enhancing the process. On the other hand, an increase in the modified bioconvection Rayleigh–Darcy number and cell eccentricity leads to a decrease in heat transfer. Furthermore, a comparison between the modulated and unmodulated systems indicates that the modulated systems have a more significant influence on the stability problem compared to the unmodulated systems. This highlights the effectiveness of external modulation in controlling heat transport within the system. [ABSTRACT FROM AUTHOR]

First morning urine (FMU) assessment would be a practical and convenient solution for clinically acceptable detection of underhydration prior to competition/training, and for the general public. Thus, we thus sought to determine the diagnostic accuracy of FMU as a valid indicator of recent (previous 24 hr, 5 days average) hydration practices. For 5 consecutive days and one final morning, 67 healthy women (n = 38) and men (n = 29; age: 20 [1] years, body mass index: 25.9 [5.5]) completed 24-hr diet logs for total water intake (from beverages and foods, absolute and relative to body mass), 24-hr urine and FMU collection (last morning only) for osmolality (Osm), specific gravity (SG), and color (Col), and morning blood sampling for plasma osmolality and copeptin. Correlations determined significance and relationship strength among FMU and all other variables. Area under the receiver operating characteristic curves, sensitivity, specificity, and positive likelihood ratios were employed using previously reported values to indicate underhydration (total water intake < 30 ml/kg, osmolality > 500, and >800 mOsm/kg, specific gravity > 1.017, and copeptin > 6.93 pmol/L). FMU_Osm and FMU_SG were significantly correlated (p <.05) to all variables except the previous 5-day plasma osmolality. FMU_Col was only significantly correlated with other color time intervals and total water intake per gram. FMU_Osm held greatest utility (area under the receiver operating characteristic curve, sensitivity, and specificity >80%) overall, with the best outcome being FMU_Osm indicating a previous 24-hr osmolality threshold of 500 mOsm/kg (FMU_Osm criterion >710 mOsm/kg and positive likelihood ratio = 5.9). With less effort and cost restriction, FMU is a viable metric to assess underhydration. [ABSTRACT FROM AUTHOR]

We investigate the source of error in the Thomas–Fermi–von Weizsäcker (TFW) density functional relative to Kohn–Sham density functional theory (DFT). In particular, through numerical studies on a range of materials, for a variety of crystal structures subject to strain and atomic displacements, we find that while the ground state electron density in TFW orbital-free DFT is close to the Kohn–Sham density, the corresponding energy deviates significantly from the Kohn–Sham value. We show that these differences are a consequence of the poor representation of the linear response within the TFW approximation for the electronic kinetic energy, confirming conjectures in the literature. In so doing, we find that the energy computed from a non-self-consistent Kohn–Sham calculation using the TFW electronic ground state density is in very good agreement with that obtained from the fully self-consistent Kohn–Sham solution. [ABSTRACT FROM AUTHOR]

Chromium nitride (CrN) is a promising structural and protective material with excellent mechanical properties and good wear and corrosion resistance. However, CrN tends to decompose into Cr 2 N at high temperatures, which makes the fabrication of single-phase and dense bulk CrN ceramics extremely challenging. In this work, a novel routine, ammonolysis followed by plasma activated sintering (PAS), has been proposed to fabricate single-phase and dense CrN ceramics. Single-phase CrN ceramics with a relative density of 98.2 %, higher than those in previous work, were successfully fabricated at the sintering temperature of 1200 °C. Its hardness and fracture toughness reach 11.9 GPa and 3.98 MPa m1/2, respectively, better than other CrN ceramics in literature. It exhibits friction coefficients of 0.75 to 0.45 and wear rates of 2.31 × 10−6 to 3.06 × 10−5 mm3 N−1 m−1 at the friction loads of 5–20 N. The successful fabrication of single-phase CrN ceramics can be attributed to the combined effect of the sintering atmosphere of extra N 2 and rapid densification. During densification, N 2 injected into the furnace will be encapsulated rapidly, creating a localized high nitrogen pressure that suppresses CrN decomposition and ultimately results in single-phase and dense CrN ceramic bulk. [ABSTRACT FROM AUTHOR]

In this paper, 3YSZ/alumina composites containing different content of alumina with different forms (powders and whiskers, respectively) were fabricated by flash sintering. The flash sintering behavior and mechanical properties of the composites were characterized and were compared with those prepared by conventional sintering. The onset temperature of the 3YSZ/alumina whiskers composites was lower than that of the 3YSZ/alumina powders composites with identical alumina content. The reason can be attributed to electrical conductivity; the conductivity of the former was lower than that of the latter. For the 3YSZ/alumina powders composites which can be densified by conventional sintering method, their relative density, Vickers hardness and fracture toughness were comparable to those prepared by flash sintering. While for the 3YSZ/alumina whiskers composites where constrained sintering existed, the flash sintering method revealed obvious advantage over the conventional sintering. A relative density of 94.5 %, hardness of 13.77 GPa and fracture toughness of 5.36 MPa m1/2 were obtained for the flash sintered 3YSZ/30 vol% alumina whisker composites. In contrast, the relative density, hardness, and fracture toughness of the conventional sintered ones were 86.4 %, 11.60 GPa and 4.82 MPa m1/2, respectively. [ABSTRACT FROM AUTHOR]

In recent years there has been a growing interest in the field of wormhole physics in the presence of Casimir effect. As this effect provides negative energy density, it can be utilized as an ideal candidate for the exotic matter required for creating a traversable wormhole. In the context of modified theories of gravity such as Brans–Dicke (BD) theory (Brans and Dicke 1961 Phys. Rev. 124 925), wormhole geometries have been vastly investigated. However, the scientific literature is silent on the issue of BD wormholes in the presence of Casimir energy. Our aim in the present study is to seek for static spherically symmetric solutions representing wormhole configurations in BD theory with Casimir energy as the supporting matter. The Casimir setup we assume comprises two electrically neutral, infinitely large parallel planes placed in a vacuum. We then consider the Casimir vacuum energy density of a scalar field in such a configuration with Dirichlet and mixed boundary conditions. In the former case the corresponding Casimir force is attractive and in the latter this force is repulsive. We present exact zero tidal force wormhole solutions as well as those with non vanishing redshift function for both types of Casimir energies. The conditions on wormhole solutions along with the weak (WEC) and null (NEC) energy conditions put constraints on the values of BD coupling parameter. These constraints are also subject to the value of BD scalar field at the throat and the throat radius. We therefore find that BD wormholes in the presence of Casimir energy can exist without violating NEC and WEC (for the repulsive Casimir force). Finally, we examine the equilibrium condition for stability of the obtained solutions using Tolman–Oppenheimer–Volkoff equation. [ABSTRACT FROM AUTHOR]

Single stabilizer-doped ZrO 2 has drawbacks such as inferior mechanical properties and thermal stability, making it difficult to obtain ZrO 2 ceramics with good density and high crystallinity. Thus, it is expected that ZrO 2 is doped and modified by two or more stabilizers. In this paper, the Sc 2 O 3 –Y 2 O 3 –ZrO 2 nanocomposite ceramic powders were prepared using ZrOCl 2 ⋅8H 2 O, ScCl 3 ⋅6H 2 O, and YCl 3 ⋅6H 2 O as raw materials and polyvinylpyrrolidone as dispersant. They calcined at diverse temperaturesby the pressureless sintering-assisted co-precipitation method after being pressed into disc shape. Sc 2 O 3 and Y 2 O 3 were added as ZrO 2 stabilizers to ameliorate the lack of insufficient mechanical properties and high-temperature stability of ZrO 2 ceramics caused by single doping. To study the stability of the phases at high temperatures, the specimens were characterized by TG-DTG, XRD, Raman, SEM, FT-IR, etc. The effects of different pH valuesand different calcination temperatures on the Sc 2 O 3 –Y 2 O 3 –ZrO 2 nanocomposite ceramics were investigated. It was demonstrated that ternary doping has very excellent phase stability. After calcination no monoclinic phase appeared, and the precursor samples were transformed from amorphous to a large amount of tetragonal phases and a few cubic phases. The samples at pH = 10 and calcination temperature of 1000 °C showed the best stabilization, the most uniform grain development, the best crystallinity, the most regular morphology, the highest tetragonal phase content of 89.2 %, the stabilization rate of 94.58 %, and the highest relative density of 98.75 %. The results show that this nanocrystalline powder can be used to prepare high-density nanoceramics. Furthermore, the activation energy for grain growth of Sc 2 O 3 –Y 2 O 3 –ZrO 2 nanocomposite ceramics was calculated as 13.87 kJ/mol. This paper provides a theoretical and experimental research basis for the controlled synthesis of Sc 2 O 3 –Y 2 O 3 –ZrO 2 nanocomposite ceramics using a pressureless sintering-assisted co-precipitation method. [ABSTRACT FROM AUTHOR]

Boron carbide-alumina (B 4 C–Al 2 O 3) composite ceramics were fabricated using boron carbide (B 4 C) as the matrix and alumina (Al 2 O 3) as the second phase by hot-press sintering at 1950 °C. The phase composition, microstructure, relative density, mechanical properties, and toughening mechanism of the composite ceramics were evaluated. When the content of Al 2 O 3 is 30 wt%, the composite ceramics show the best comprehensive mechanical properties. The relative density, Vickers hardness, flexural strength, and fracture toughness of the obtained B 4 C-30 wt%Al 2 O 3 composite ceramics reach up to 98.8 %, 24.7 GPa, 477 MPa, and 4.64 MPa m1/2, respectively. The introduction of Al 2 O 3 as the second phase can significantly improve the fracture toughness of the B 4 C ceramics. Firstly, when cracks extend to the Al 2 O 3 grains, the cleavage fracture of the Al 2 O 3 grains resulting from its crystal structure causes the crack deflection along the cleavage plane. Secondly, due to the mismatch of the coefficient of thermal expansion between B 4 C and Al 2 O 3 , residual stress is generated at the grain boundary of the two phases and within the grains. The tensile stress at the grain boundary can cause some cracks to extend along the grain boundary, making cracks deflected, and the compressive stress within the B 4 C grains can inhibit crack extension. Thirdly, submicron-sized Al 2 O 3 grains wrapped within the B 4 C grains form a subboundary structure, which can lead to crack extension along the subboundary. All of these factors consume the crack extension energy, which can contribute to increasing the fracture toughness of B 4 C–Al 2 O 3 composite ceramics. [ABSTRACT FROM AUTHOR]

A novel low- ε r Zn 3 Ga 2 SnO 8 ceramic was prepared, and the phase composition and microstructural evolution were investigated. According to Rietveld refinement, TEM, and Raman spectroscopy, Zn 3 Ga 2 SnO 8 ceramics had a cubic spinel structure in which Zn1 occupied the tetrahedral sites, and Zn2/Ga1/Sn1 occupied the octahedral sites. The relative density and packing fraction significantly influence the ε r and Q × f of Zn 3 Ga 2 SnO 8 ceramics, respectively. Meanwhile, the P–V–L theory indicates that the contribution rate of Sn–O bonds to bond ionicity is 29.2 %, and that of Ga–O bonds to lattice energy is 37.5 %. The Zn 3 Ga 2 SnO 8 ceramics exhibit the best microwave dielectric properties (ε r = 10.6, Q × f = 88,725 GHz, and τ f = −25.1 ppm/°C) when sintered at 1320 °C. Given these advantages, Zn 3 Ga 2 SnO 8 ceramic has certain potential applications in millimeter-wave technology. [ABSTRACT FROM AUTHOR]

AlN/h-BN composite ceramics exhibit considerable anisotropy, which significantly constrains their application in areas such as semiconductor packaging and light-emitting diodes. The introduction of c-BN can significantly enhance mechanical properties and effectively reduce the anisotropy. However, this results in lower thermal conductivity, which is important issue that needs to be addressed. In this study, hot-press sintering was employed to fabricate AlN-10 wt% h-BN-15 wt% c-BN- x wt.% Y 2 O 3 (AB15C x Y, with x = 0, 1, 2, 3, 4) composite ceramics. Effects of Y 2 O 3 content on microstructure, anisotropy, thermal conductivity, and flexural strength of AlN/BN composite ceramics were systematically investigated. Results indicate that during high-temperature sintering, c-BN undergoes phase transformation into "onion-like'' h-BN, and Y 2 O 3 reacts with Al 2 O 3 film on the surface of AlN powder to form Y 3 Al 5 O 12 (YAG) phase. YAG phase promotes sintering densification as well as directional arrangement of lamellar h-BN, endowing composite ceramics with relative density of 99.6 % (sample AB15C1Y) with increased degree of anisotropy (the index of orientation preference is | IOP | = 68–93). Thermal conductivity of AlN/BN composite ceramics is directly correlated with lattice oxygen content, and as Y 2 O 3 content increases, lattice oxygen content decreases monotonically. Lattice oxygen content of sample AB15C3Y is as low as 0.35 wt%, and the maximum values of K ∥ and K ⊥ are 100 and 59 W‧m−1‧K−1, respectively, which represent increases of 64.8 % and 51.3 % compared with those of AB15C0Y ceramic, respectively. With the increase in Y 2 O 3 content, AlN grains become gradually larger, and the proportion of YAG phase, which is characterized by brittle grain boundaries, increases, leading to gradual reduction in the flexural strength of AlN/BN composite ceramics. [ABSTRACT FROM AUTHOR]

To date, the application of additive manufacturing techniques in fabricating SiAlON ceramics with intricate geometries has been limited. This investigation demonstrates the synthesis of SiAlON ceramics by integrating silicon nitride (Si 3 N 4) powders with variable proportions of aluminum nitride (AlN) utilizing the vat photopolymerization (VPP) approach. The effects of AlN content on the properties of SiAlON ceramic slurries, green bodies, and sintered parts were systematically investigated. Notably, the slurry's viscosity decreases progressively with an increase in AlN, aligning with VPP printing prerequisites. Additionally, the curing depth of the slurry enhanced proportionally with AlN augmentation, elevating from 21 μm to 44 μm at an energy exposure of 800 mJ/cm2, with the pivotal addition being 15 vol% AlN, where optimal properties were achieved. The zeniths of flexural strength, bulk density, relative density, and thermal conductivity were recorded at 385.66 ± 22.63 MPa, 3.34 ± 0.09 g/cm3, 96.22 ± 2.55 %, and 37.4 ± 0.31 W m−1 K−1, respectively. The fabrication of SiAlON ceramics with complex configurations was successfully realized, heralding a novel methodology for future SiAlON ceramic production. [ABSTRACT FROM AUTHOR]

In this study, we first developed an artificial intelligence (AI) that estimates relative densities (RD) of silicon nitride ceramics from the process conditions. We then constructed a multi-layer AI that predicts the thermal conductivities (TC) from the above process conditions using an RD obtained by the developed AI. The RD-predictive AI utilized input data (explanatory variables) which represent the effects of main powders, sintering additives, organic sacrificial pore formers and heat treatments (nitriding and/or sintering), whereas the TC-predictive AI exploited the predicted RD as well as the aforementioned explanatory variables. Both the AIs successfully improved the prediction accuracy by incorporating the types and concentrations of sintering additives and conditions into the explanatory variables. These AIs exhibit potential to predict even other properties of silicon nitride ceramics prior to the real fabrication. [ABSTRACT FROM AUTHOR]

The typical high-density zirconium carbide (ZrC) ceramic requires high temperature and high pressure, leading to high manufacturing cost for complex shapes. Herein, nano-sized carbon layer encapsulated ZrC particles were pressureless sintered to achieve near-net preparation of high-density and complex-shape ZrC ceramic. The results indicate that reaction between carbon layer and the ZrC x O y phase in ZrC was improved because the carbon layer shortened the oxygen diffusion pathway. The oxygen content decreased from 3.52 wt% to 0.82 wt% while the thickness of carbon layer decreased from 4.0 nm to 0.75 nm after sintering at 1950 °C for 1 h. Furthermore, the migration of oxygen from ZrC x O y phase to the carbon layer effectively facilitate the formation and growth of the sintering neck. The resulting ZrC ceramic exhibited a high relative density of 92.3 % and excellent mechanical properties. The Vickers hardness, indentation fracture toughness, micro hardness, elastic modulus, and flexural strength were 17.3 ± 0.7 GPa, 4.0 ± 0.5 MPa m1/2, 22.2 ± 2.4 GPa, 429.9 ± 20.7 GPa, and 324 ± 8 MPa, respectively. This work provides a novel perspective to fabricate near-net, high-density and complex-shape ZrC ceramic at lower temperature without pressure. [ABSTRACT FROM AUTHOR]

The main concern of this paper is to study large-time behavior of solutions for an outflow problem to the reduced gravity two and a half layer model in a half space. We establish the existence of stationary solutions and further obtain the large time asymptotic stability of small-amplitude stationary solutions provided that the initial perturbation is sufficiently small. Moreover, we obtain the convergence rate of the solution toward the stationary solution in some weighted Sobolev spaces only for the supersonic case. The proof is based on the basic energy method. A key point for the proof of convergence rates is to capture the positivity of the temporal energy dissipation functional and boundary terms with suitable space weight functions either algebraic or exponential depending on whether or not the incoming far-field velocity satisfy some additional conditions. [ABSTRACT FROM AUTHOR]

The task of the study was to test new demulsifying compositions for high pyrolysis coal tars originally intended for separating emulsions based on heavy petroleum oils. Coal tars with a specific gravity of 1.243–1.261 were investigated and light coal tar with a specific gravity of 1.185 was used for comparison. Demulsifying compositions for heavy media were prepared on the basis of Dissolvan (Clariant) reagents, "PM" demulsifier was used as a main indicative reagent for breaking of light coal tar emulsions. To determine the efficiency of dewatering a "bottle test" was applied, Fourier transform infrared spectroscopy analysis of the distillate residues was performed to determine the functional group of potential stabilizers. The composition of the mineralized and dispersed solid stabilizers was determined by X-ray fluorescence (XRF) spectrometry. The results showed that for the heavy coal tar emulsions, some compositions based on oxalkylated resin showed high activity and separated up to 17–19% of water, in contrast to the indicative demulsifier 0–3%. An attempt has been made to investigate the mineral composition of emulsion stabilizers transferred into the water part and remaining in the coal tar (sludge). The results of XRF spectrometry suggested that Zn-pyridine compounds are the most likely hydrophile stabilizers of heavy coal tar emulsions. [ABSTRACT FROM AUTHOR]

A rapid, cost-effective and eco-friendly approach for fabricating SiC using Si particles derived from Si scrap is highly recommended from both economic and environmental standpoints. Herein, we demonstrate the fabrication of β-SiC effectively in argon atmosphere at 1500°C by utilizing combustion synthesis followed by flash sintering in a single-step experiment for the first time. Synthesis of β-SiC was relied on exothermic reaction between Si and C elements present in the powder compact whereas densification was accomplished eventually through flash sintering. In addition, the effects of different flash sintering conditions on the properties of β-SiC are examined with and without Y 2 O 3 sintering additive. A high relative density of 85% was realized when a current density of 60 mA/mm2 was applied for 60 min with Y 2 O 3 addition. This novel one-step fabrication approach has the potential to reduce production cost of β-SiC significantly and has both commercial and environmental advantages. [ABSTRACT FROM AUTHOR]

Solid-state electrolyte structures using sodium polyaluminate ceramics, have been fabricated for the first time using direct ink writing; a material extrusion-based additive manufacturing process. A series of test samples were prepared using a high solids loading (80 wt%; 51.2 vol%) ceramic paste formulations with suitable rheological characteristics for 3D printing. Following optimum densification via conventional sintering at 1600 °C for 30 min, the additively manufactured electrolyte test samples exhibited an ionic conductivity of σ = 0.14 ± 0.019 S·cm−1 at 300 °C and density of ρ = 3.1 ± 0.02 g·cm−3 (relative density of 95%). These results suggest that direct ink writing of sodium polyaluminates is a promising approach for electrolyte manufacture. Additionally, this approach shows great potential for manufacturing complete solid-state battery structures, through multi-material direct ink writing. [ABSTRACT FROM AUTHOR]

An innovative sintering technique, the Cold Sintering Process (CSP), has been employed to obtain dense Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 (LATP) Solid-State Electrolytes (SSE) by optimising the particle size (d 50) of the starting powder. The CSP is carried out at 700 MPa, 150 ºC, and 90 min of sintering time, using acetic acid solution as Transient Liquid Phase (TLP). The CSP lowers the LATP sintering temperatures almost 1000 ºC. To study the electrical properties, an in operando Electrochemical Impedance Spectroscopy (EIS) technique has been used. The optimum d 50 is 0.415 µm, yielding to competitive microstructure and electrical properties (ionic conductivity of 6.93·10−5 S cm−1 at 30 ºC, activation energy of 0.363 eV, and a relative density of 81.2 ± 0.8%). Relative density, ionic conductivity and TLP content must be balanced, because at small d 50 , although relative density is enhanced the ionic conductivity is reduced. A packing model has been used to understand this behaviour and the mass transfer mechanisms. [Display omitted] • Cold Sintering Process method to sinter LATP Solid Electrolyte. • Combination of 3 cornerstones: particle size, CSP and in operando impedance. • Effect of particle size on microstructure and electrical properties. • Dissolution-precipitation mechanisms involving the Cold Sintering Process. [ABSTRACT FROM AUTHOR]

We investigate the quantum modified cosmological dynamical equations in a Friedmann–Lemaître–Robertson–Walker universe filled with a barotropic fluid and a general non-canonical scalar field characterized by a Lagrangian similar to k-essence model but with a potential term. Quantum corrections are incorporated by considering the running of the gravitational and potential couplings, employing the functional renormalization group approach. Covariant conservation of the non-canonical scalar field and the background barotropic fluid is considered separately, imposing a constraint resulting from the Bianchi identity. This constraint determines the evolution of the cut-off scale with the scale factor and also reveals the cosmic fixed points, depending on whether the flow ceases or continues to evolve. We explore how the general non-canonical scalar field parameter affects the different types of cosmic fixed points and how it differs from the canonical case. Furthermore, we establish a bound on the ratio of the renormalization group parameters involving the non-canonical parameter for which the universe may exhibit accelerated expansion for mixed fixed points. This bound indicates the non-canonical scalar field includes larger sets of asymptotically safe renormalization group fixed point which may give rise to an accelerated universe. [ABSTRACT FROM AUTHOR]

The current research identify the disturbances in a rotating two-dimensional nonhomogeneous, orthotropic thermoelastic solid half-space with gravity field in the context of Green and Lindsay (G-L) theory. A mechanical source is acting on the surface of the half-space. It is presumed that the mechanical and thermal properties are varying in the x-direction. With the application of normal mode analysis, different field variables are obtained in the physical domain. These field variables are also computed numerically with the help of MATLAB programming. Some collations are made to delineate the effects of anisotropy, non-homogeneity, gravity and rotation parameters on the physical fields. [ABSTRACT FROM AUTHOR]

We explore the survival of a galaxy's circumgalactic medium (CGM) as it experiences ram pressure stripping (RPS) moving through the intracluster medium (ICM). For a satellite galaxy, the CGM is often assumed to be entirely stripped/evaporated, an assumption that may not always be justified. We carry out 3D-hydrodynamic simulations of the interstellar and circumgalactic media (ISM + CGM) of a galaxy like JO201 moving through the ICM. The CGM can survive long at cluster outskirts (⁠|$\gtrsim 2 \rm \ Gyr$|⁠) but at smaller clustercentric distances, 90 per cent of the CGM mass is lost within ∼500 Myr. The gravitational restoring force on the CGM is mostly negligible and the CGM–ICM interaction is analogous to 'cloud–wind interaction'. The CGM stripping time-scale does not depend on the ram pressure but on the CGM to ICM density contrast χ. Two distinct regimes emerge for CGM stripping: the χ > 1 regime, which is the well-known 'cloud crushing' problem, and the χ < 1 regime, which we refer to as the (relatively unexplored) 'bubble drag' problem. The first pericentric passage near the cluster core can rapidly – over a crossing time t drag ∼ R / v rel – strip the CGM in the bubble drag regime. The ISM stripping criterion unlike the CGM criterion, still depends on the ram pressure |$\rho _{\rm ICM} v_{\rm rel}^2$|⁠. The stripped tails of satellites contain contributions from both the disc and the CGM. The X-ray plume in M89 in the Virgo cluster and a lack of it in the nearby M90 might be attributed to their orbital histories. M90 has likely undergone stripping in the bubble drag regime due to a pericentric passage close to the cluster centre. [ABSTRACT FROM AUTHOR]

The current study investigated the impact of Saccharomyces cerevisiae fermentation on apricot kernel oil extraction and the resulting quality characteristics of the oil. The seed kernels underwent physicochemical and antioxidant studies after being separated, gelatinized, and fermented. The results revealed 43.6 % of oil yield by fermentation. The extracted oil had a lower acid value (3.74 mg KOH/g), and peroxide value (4.25 meq/kg). The investigation of additional oil properties was included, like iodine value (100.26 mg KOH/g), saponification value (190.5 mg KOH/g), specific gravity (0.919), viscosity (4.62), moisture content (0.592 %), and refractive index (1.4836), which signifies optimum physicochemical parameters of oil. As per the FTIR data, some distinct functional groups like C-H stretch and C O, C C, CH3, OH, and R-O-R esters were found in the extracted oil. The oil's fatty acid composition, with 50.47 % saturated, 22.23 % mono-unsaturated, and 35.13 % polyunsaturated fatty acids, enhances stability, oxidative resistance, and nutritional value, justifying its favorable physicochemical properties. The DPPH radical scavenging activity of the oil showed to have good antioxidant activity. Metabolic modeling of S. cerevisiae provided information about compounds received after fermentation. Hence, it can be concluded that fermentation is a suitable approach to extract apricot seed kernel oil with beneficial properties. [Display omitted] • Apricot seed kernel is a good source of oil, we can use it for multiple purposes. • Saccharomyces cerevisiae -based fermentation, we can get 43.6 % of oil. • Different beneficial fatty acids were obtained from this oil: Caprylic, Lauric, Margaric, Paullinic, Phthalic acid, etc. [ABSTRACT FROM AUTHOR]

Objective: Plasma copeptin is a relatively new biomarker for evaluation of arginine vasopressin (AVP) secretion. The aim of this study was to test the diagnostic performance of copeptin in patients with polyuria‐polydipsia syndrome. Design, Patients and Measurements: This was a prospective study where 88 patients with polyuria‐polydipsia syndrome were evaluated with a water deprivation test (WDT). Weight, urine osmolality, urine specific gravity, and plasma copeptin were collected at baseline, after 8 h, and at termination of the WDT when one of the following had been reached: (i) >3% weight reduction, (ii) urine specific gravity >1.017 or urine osmolality >600 mOsm/kg, or (iii) intolerable adverse symptoms. Results: Of 88 patients (57 women), 21 (24%) were diagnosed with central diabetes insipidus (cDI), 5 (6%) with nephrogenic DI (nDI), and 62 (71%) with primary polydipsia (PP). Median (interquartile range) copeptin at baseline was 1.7 (1.4–2.5) pmol/L in cDI, 22 (18–65) pmol/L in nDI, and 2.7 (2–4) pmol/L in PP. After 8 h of WDT, the highest copeptin in patients with cDI was 4.0 pmol/L. In patients with PP: (i) 41 had urine osmolality <600 mOsm/kg, 7 (17%) of these had copeptin >4.0 pmol/L, (ii) 21 had urine osmolality ≥600 mOsm/kg, 14 (67%) of these had copeptin >4.0 pmol/L. Conclusions: Copeptin >4.0 pmol/L after an overnight WDT can be used to rule out cDI and copeptin ≥21 pmol/L at baseline to diagnose nDI. The diagnostic performance of copeptin in the context of the WDT is otherwise limited in the diagnostic work‐up of patients with polyuria‐polydipsia syndrome. [ABSTRACT FROM AUTHOR]

The quality of asphalt pavement (HMA) is often assessed by its dielectric permittivity, e.g., using ground-penetrating radar technology. The mostly employed relationships were developed for dry HMA pavement as follows: Complex Refractive Index Model (CRIM), Bottcher, Rayleigh, and Al-Qadi–Lahouar–Leng models (so-called ALL model), while the relationships for the estimation of wet HMA properties are empiric and not consistent with those for dry HMA mixtures. The article presents the results of the development and analysis of novel relationships between the values of dielectric permittivity and the mechanical characteristics of wet asphalt. It is shown that the new relationships are the general consistent cases of the expressions previously developed for dry HMA. The new expressions for the Rayleigh and ALL models are shown providing close estimates for the value of moisture content in the range of porosity and degree of water saturation: 0–0.12 and 0–1, respectively, and in the wide range of aggregate specific gravity (2.5–2.9), the binder content (0.04–0.08), the dielectric permittivity of aggregate (6–11), and the maximum specific gravity (2.5–2.9). Since the ALL model is an implicit function, in which the dielectric permittivity variable cannot be extracted, the direct problem (to calculate the dielectric constant value from density/specific gravity and porosity value) can be solved numerically while the inverse problem can be solved algebraically. The newly developed expression for the Rayleigh model (for wet asphalt) can be used for the estimation of dielectric permittivity based on expected values of porosity and density, and vice versa, and hence it is simpler for using. [ABSTRACT FROM AUTHOR]

The main goal of this study is to investigate the strength and compaction characteristics of soil stabilized by fly ash with multiwalled carbon nanotube (MWCNT) as an additive. The materials used in the study were characterized using microscopic techniques like scanning electron microscopy-energy dispersive spectroscopy (SEM–EDS), and X-ray diffraction (XRD). The soil in the current study was replaced up to 50% by fly ash in the presence of MWCNT and sodium hexametaphosphate (SHMP) in different concentrations. The findings demonstrate that the Atterberg limits and specific gravity decrease with the increase in fly ash, MWCNT, and, SHMP. The maximum (46%) and minimum (24.2%) values of the liquid limit were recorded at 0% and 50% fly ash content, respectively. The maximum (34%) and minimum (20.2%) values of the plastic limit were observed at 0% and 50% fly ash content respectively. The specific gravity of natural soil decreases from the maximum value of 2.68 to the minimum value of 2.53 at 0% and 50% fly ash content, respectively. The optimum moisture content also decreases with the increase in fly ash, MWCNT, SHMP, and vice versa for maximum dry density. 0.01% w/w MWCNT + 80% Soil + 20% Fly Ash + 2% SHMP is the optimal mix. It gives maximum unconfined compressive strength (UCS) value in all the durations of curing, i.e. 0.50, 0.725, and 0.984 MPa at 1, 7, and 28 days of curing, respectively. The UCS value of this combination is 147% more than the UCS value of normal soil cured for 28 days. An economic analysis is also conducted to understand the feasibility of the application of MWCNTs in soil-fly ash mix. [ABSTRACT FROM AUTHOR]

The primary objective of this paper is to examine singularity-free solutions within the framework of anisotropic solutions for the Chaplygin equation of state in f (R , ϕ , X) modified gravity theory. Herein, R signifies the Ricci scalar, ϕ denotes the scalar field, and X represents the kinetic term associated with ϕ. The investigation employs the Krori–Barua metric to explore the characteristics of an anisotropic compact star. In the course of our analysis, we specifically consider observational data about three distinct stellar structures: Her X-I, LMC X-4, and 4U 1538-52. Our inquiry extends to the graphical examination of various physical parameters, encompassing energy density, pressure components, anisotropic components, equation of state parameters, equilibrium conditions, stability analysis, adiabatic index, and energy conditions. Furthermore, we delve into the intricacies of the mass-radius function, compactness factor, and surface redshift–integral features of charged compact stars. The culmination of our findings suggests that the f (R , ϕ , X) theory of gravity when subjected to observational scrutiny, manifests as realistic, stable, and devoid of singularities. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the conditions for mapping the geometric description of the kinematics of particles that probe a given Hamiltonian in phase space to a description in terms of Finsler geometry (and vice-versa). [ABSTRACT FROM AUTHOR]

In this paper, we review a recently offered notion of quasi-static evolution of the axial self-gravitating structures at large scales and the criterium to characterize the corresponding evolutionary aspects under the influence of strong curvature regimes. In doing so, we examine the axial source's dynamic and quasi-static behavior within the parameters of various modified gravity theories. We address the formalism of these notions and their possible implications in studying the dissipative and anisotropic configuration. We initiate by considering higher-order curvature gravity. The Palatini formalism of f (R) gravity is also taken into consideration to analyze the behavior of the kinematical as well as the dynamical variables of the proposed problem. The set of invariant velocities is defined to comprehend the concept of quasi-static approximation that enhances the stability of the system in contrast to the dynamic mode. It is identified that vorticity and distinct versions of the structure scalars Y I , Y II and Y KL play an important role in revealing the significant effects of a fluid's anisotropy. As another example of evolution, we check the influence of Palatini-based factors on the shearing motion of the object. A comparison-based study of the physical nature of distinct curvature factors on the propagation of the axial source is exhibited. This provides the intriguing platform to grasp the notion of quasi-static evolution together with the distinct curvature factors at current time scenario. The importance of slowly evolving axially symmetric regimes will be addressed through the distinct modified gravitational context. Finally, we share a list of queries that, we believe, deserve to be addressed in the near future. [ABSTRACT FROM AUTHOR]

Boron carbide with high relative density was prepared in situ using spark plasma sintering. Research on the in-situ reaction of boron and carbon nanotubes reveals that the reaction exhibits high reactivity at 1200 °C. Beyond this temperature, increasing the external pressure was beneficial for particle rearrangement, gas release, and dislocation formation. The result of mechanical properties shows that, the flexural strength and fracture toughness of the boron carbides are 656 ± 9 MPa and 5.0 ± 0.3 MPa m1/2, respectively, when sintered at 1750 °C under continuous pressure ramping conditions–an increase of 64.1% and 46.6% compared to that prepared under constant pressure conditions. Increasing the magnitude of the external stress during the in-situ reaction process can also enhance the particle rearrangement efficiency, inducing the formation of twinning and stacking faults in boron carbide ceramics. High–density twinning and stacking faults dominated the toughening mechanisms of ceramic materials. [ABSTRACT FROM AUTHOR]

Employed ubiquitously in oral restorations, zirconia-based bioceramics face challenges with low-temperature degradation (LTD) in the tetragonal phase (t-ZrO 2) within oral environments. In order to improve the resistance of ZrO 2 ceramics to LTD, this study utilized vat photopolymerization technology to prepare 7Ce3Y–ZrO 2 (7 mol% CeO 2 and 3 mol% Y 2 O 3). By adjusting the dispersant content and photosensitive resin ratio enabled the attainment of a 63.5 μm curing depth with a 400 mJ/cm2 exposure, meeting the requirements for vat photopolymerization printing. After sintering at 1550 °C, these ceramics shown a relative density of 97.84 % and an impressive flexural strength of 503.1 MPa. Accelerated LTD tests were conducted to assess LTD-resistance, revealing no degradation in mechanical properties or evidence of tetragonal to monoclinic phase transitions. This stability is credited to the cerium ions' efficacy in hindering oxygen vacancy formation and subsequent aging within the ZrO 2. This study affirms that CeO 2 –Y 2 O 3 co-stabilized ZrO 2 ceramics prepared using vat photopolymerization technology exhibit outstanding properties and resistance to LTD, showcasing significant potential in the field of oral restoration. [ABSTRACT FROM AUTHOR]

Zirconia dental ceramics incorporated with inert dental glass (IDG) were fabricated by digital light processing (DLP). The effects of the amount of added IDG on the physical properties and microstructure of sintered samples were investigated. Highly dense zirconia dental ceramic samples with a relative density of 98.9% were obtained by adding different amounts of IDG sintered at 1500°C. With the addition of 1 wt% IDG, the Vickers hardness, fracture toughness, and wear resistance increased to 13.03 GPa, 6.33 MPa m1/2, and 0.03 mg/(mm2 min), respectively. However, with the incremental addition of IDG at 3 and 5 wt%, a slight reduction in Vickers hardness, fracture toughness, and wear resistance was observed. The values recorded were 12.68 GPa, 5.90 MPa m1/2, and 0.05 mg/(mm2 min) for the former, and 11.86 GPa, 5.48 MPa m1/2, and 0.06 mg/(mm2 min) for the latter. Scanning electron microscopy observation suggested that 1 wt% IDG incorporated into zirconia dental ceramic samples resulted in an optimal microstructure, with IDG existing at triple junctions of zirconia grains to form a discrete secondary phase. The broken surface revealed transgranular fracture features. This investigation indicates that adding a proper amount of IDG is an effective method to enhance the properties of DLP‐fabricated zirconia dental ceramics. [ABSTRACT FROM AUTHOR]

Lithium (Li)‐doped boron carbide (B4C) has generated widespread attention for its potential to enhance mechanical properties. Nevertheless, the influence of the Li solid solution on the microstructure and mechanical properties of B4C ceramics remain unclear. In this research, the microstructure of Li‐doped B4C was investigated in meticulous detail. Through X‐ray diffraction, X‐ray photoelectron spectroscopy, and Raman spectroscopy analysis, it was confirmed that Li successfully solubilized in B4C at 1 500°C under 50 MPa for an 8 min, resulting in lattice expansion. Further insights from electron energy loss spectroscopy revealed the integration of Li into the crystal lattice and alterations in the C–B–C chains. Furthermore, the Li2O content significantly affected the densification and microstructure of B4C. Relative density increased from 91.2% (B4C) to 99.2% (9 wt.% Li2O–B4C), accompanied by a transition from a few intragranular planar defects to high‐density twins. Mechanical property tests demonstrated that 9 wt.% Li2O–B4C exhibited optimal comprehensive mechanical performance, with a flexural strength of 533 ± 27 MPa, fracture toughness of 3.71 ± 0.29 MPa∙m1/2, hardness of 33.3 ± 0.6 GPa, and a density of just 2.45 g/cm3, surpassing that of pure B4C. [ABSTRACT FROM AUTHOR]

This study focuses on the design, additive manufacturing, and characterization of silicon carbide‐based components with complex geometries. These parts were produced using a novel hybrid technique, previously developed: powder bed fusion of polyamide was used to 3D print two different templates with complex architectures. Preceramic polymer infiltrations and pyrolysis with polycarbosilane and furan resin were performed to obtain the ceramic parts. The final densification was achieved with reactive or nonreactive silicon infiltrations according to four different strategies, producing ceramics comprised of crystalline βSiC, reaction‐bonded βSiC, and low residual silicon. The final gyroid samples (∼70 vol% macroporosity) exhibited a maximum compressive strength of 24.7 ± 2.2 MPa, with a skeleton density of 3.173 ± 0.022 g/cm3, and a relative density of 0.935 ± 0.016. These findings underscore the potential of this manufacturing approach and showcase its effectiveness in fabricating intricate ceramic structures for engineering applications as heat exchangers and catalytic supports. [ABSTRACT FROM AUTHOR]

The dicalcium phosphate anhydrous (DCPA, CaHPO4) bioceramic has long been difficult to prepare by conventional sintering techniques due to its weak thermal stability. Here, the DCPA ceramic is prepared at 250°C by cold sintering process (CSP) using the dicalcium phosphate dihydrate (DCPD, CaHPO4·2H2O) as the starting powder. It is found that the dehydration temperature of DCPD powder is greatly reduced during CSP, which facilitates the densification even without additive water. However, the ceramic only reaches a relatively low density of around 90% without additive water, which can be ascribed to the lack of particle rearrangement and the readily loss of dehydration water during sintering. In comparison, a high relative density of 95% can be obtained when the DCPD hydrate is densified with additive water, in which both hydration water and additive water play important roles. The obtained DCPA ceramic with high density exhibits a flexural strength of 46.17 MPa and Young's modulus closer to human bones compared with hydroxyapatite. Combined with the low cytotoxicity, the DCPA bioceramic has great potential to be applied for bone tissue engineering. [ABSTRACT FROM AUTHOR]

The phase‐field method was employed to simulate the effects of pores on grain growth in the indium gallium zinc oxide (IGZO) targets during conventional and two‐stage sintering (TSS). The findings indicated that the TSS method effectively suppressed the rapid growth of grains. With an increase in porosity and a more prominent pore size, the rate of grain growth accelerated, resulting in the formation of coarser grains. Subsequently, IGZO targets were fabricated using the molding‐cold isostatic pressing (CIP) and TSS methods. The densification activation energies of IGZO green compacts were calculated to be 510 and 370 kJ/mol for CIP at 180 and 250 MPa, respectively, utilizing the main sintering curve (MSC). Additionally, by optimizing the TSS process, a highly dense IGZO target with a relative density of 99.53%, a resistivity of 4.3 mΩ/cm, and an average grain size of 8.59 µm was successfully achieved. [ABSTRACT FROM AUTHOR]

In this paper, we present the first nontrivial lower bound on the translative covering density of tetrahedra. To this end, we show the lower bound, in any translative covering of tetrahedra, on the density relative to a given cube. The resulting lower bound on the translative covering density of tetrahedra is 1 + 1.227 × 10 - 3 . [ABSTRACT FROM AUTHOR]

The possibility of setting up a space experiment aimed at detecting ultra-small deviations of the law of gravity of the central star of the planetary system from the Newton and Schwarzschild formats is demonstrated. The experiment comprises a ballistic flight of a space-probe along a trajectory composed of three treks divided by two gravity assist (GA) maneuvers at different planets, each GA acting as a powerful amplifier of the probe deflections caused by small deviations of the gravitational law. It is shown that the proposed (different) analytical and numerical computations of the probe's flight in a model of a planetary system simulating the Sun, Earth, and Venus, give similar results confirming a certain possibility to distinguish the forces of gravity described by the Schwarzschild and Eddington-Robertson metrics. • A space experiment to detect deviations from a 'standard' gravity law is discussed. • The Sun, Earth, Venus in Eddington or Schwarzschild gravity make up the space lab. • The experiment scheme of a probe flight with two gravity assists (GA) is suggested. • Analytical & numerical computations of the probe flight are made with close results. • Two GAs at Venus and Earth definitely distinguish between the regarded gravity laws. [ABSTRACT FROM AUTHOR]

The present work investigates the combined effect of varying gravity and heat flux direction with respect to gravity on the melting dynamics of Phase Change Material. Similar conditions are relevant to applications in space, at different space infrastructures, such as orbiting satellites, as well as various extraterrestrial surface assets, landers, and rovers. The numerical simulations are performed to study the melting dynamics of a paraffin-based phase change material with Prandtl number Pr ≈ 71 and Stefan number Ste ≈ 0.33 inside a differentially heated square enclosure. The mathematical model employs a control volume-based enthalpy porosity approach to simulate the melting process inside enclosure. The direction of the incoming heat flux relative to the gravity vector is defined in terms of an orientation angle, which is varying circularly with a step of 45°, whereas the gravity level is ranging from the terrestrial surface value g to 0.2 g to analyze the melting process over a wide range of Rayleigh number 100 ≤ Ra ≤ 107. The study provides a detailed insight into the attributes of heat transfer, flow dynamics, and energy storage, along with a quantitative analysis of the transition between various melting regimes and temporal fluctuations in the performance parameters. The findings demonstrate that the mutual orientation between the directions of incoming heat flux and gravity, as well as the value of the latter, significantly affect features of the convective motion in the liquid phase, as well as the entire thermally driven heat transfer within the domain. In particular, for the oppositely directed gravity and heat flux, the melted fluid closely resembles Rayleigh-Bénard convection with the presence of multicellular flow structures, while at other orientation angles, except for a co-directed gravity and heat flux case, a circular convective motion of the melted fluid takes place. The results of numerical simulations reveal declining melting rates as the mutual orientation of gravity and heat flux changes from opposite to co-directed and vice versa. The low gravity conditions delay the onset of convection-driven melting, reducing the melting rate significantly. • Effect of heat flux direction and varied gravity on PCM melting dynamics is studied. • Paraffin-based PCM (Pr ≈ 71, Ste ≈ 0.33) filled inside square enclosure is investigated. • Study considers orientation angle range (0 ° to 315 °) and gravity level (0.2g to g). • A detailed analysis of thermal, flow, and energy storage attributes is presented. • Results reveal details useful for designing thermal control for space applications. [ABSTRACT FROM AUTHOR]