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Multi-criteria optimization is used for developing molecular models for ethylene carbonate (EC) and propylene carbonate (PC), organic solvents commonly used in Li-ion batteries. The molecular geometry and partial charges of the solvents are obtained from quantum mechanical calculations. Using a novel optimization strategy that combines systematic variations of the Lennard-Jones parameters with a reduced units approach, the models are fitted to experimental data on the liquid density, vapor pressure, relative permittivity, and self-diffusion coefficient. Since no experimental data for the self-diffusion coefficient of pure EC were available in the literature, they are measured in this work using a gradient-based nuclear magnetic resonance technique. For all pure component properties, excellent agreement between experiment and simulation is obtained. Moreover, the predictive capabilities of the new solvent models are assessed by comparison to experimental data for the liquid density and relative permittivity of mixtures of EC and PC. In addition, molecular models for the anions P F 6 − , B F 4 − , and C l O 4 − in solutions of their lithium electrolytes in PC are developed using experimental data on the solution densities. Finally, the self-diffusion coefficients of LiPF6 in PC and in aqueous solution are predicted and compared, showing that diffusion is much slower in the organic solution due to the formation of larger solvent shells around the ions. Furthermore, an analysis of the radial distribution functions in these solutions suggests that the ions have much less impact on the structure of the solvent PC than on water. [ABSTRACT FROM AUTHOR]

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]

Purpose: We examined fluid intake, the relation between body mass (BM) loss and performance, and core temperature in young triathletes during a competition in tropical climate. Methods: Fluid intake and pre and post BM were measured in 35 adolescent athletes, and core temperature was measured in one female and one male. Results: Mean urine specific gravity (1.024 [0.007]) indicated that athletes were in suboptimal state of hydration upon waking. Race time was 73.2 (8.0) minutes. BM decreased by 0.6 (0.3) kg (P <.05). Fluid intake (528.5 [221.6] mL) replaced 47% of the fluid loss (1184.9 [256.4] mL) and was higher during run (11.5 [6.6] mL·min−1) compared to bike (7.3 [3.1] mL·min−1), P <.01. Loss in BM was ≥1.0% in 66% and ≥1.5% in 29% of the athletes. Males showed a moderate association between percentage loss in BM and finishing time (r = −.52), higher sweat rates (1.0 [0.3] L·h−1), and faster times (69.4 [7.5] min; P <.05). Core temperature rose to 40.1 °C in the female and 39.6 °C in the male. Conclusion: Young triathletes competing in a hot/humid climate became mildly to moderately dehydrated and hyperthermic even when water and sports drinks were available but did not show symptoms of heat illness. [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]

Various approaches have been developed to address the challenges of difficult densification in traditional BaZrO 3 -based and BaCeO 3 -based protonic ceramic fuel cells (PCFCs) electrolytes. The addition of sintering additives, the most widely used approach, has been found to potentially compromise electrical performance while improving sinterability in traditional sintering. Recently, SrSn 0.8 Sc 0.2 O 3- δ (SSS) has emerged as a promising proton-conductor material; however, there is still space for improvement in its electrical and sintering properties. In this study, a systematic investigation was conducted into the effect of sintering additives (NiO, ZnO, CuO) on the electrical performance of the new proton conductor SSS. Notably, SSS-1wt%NiO was found to decrease the sintering temperature from 1600 °C to 1400 °C (reaching 92 % relative density) and increase protonic conductivity from 2.61 × 10−3 S cm−1 to 3.06 × 10−3 S cm−1 at 600 °C, without any increase in electronic conductivity. This demonstrates a synergistic beneficial effect on both sinterability and electrical properties. Furthermore, the Ni-SSS|SSS-1wt%NiO|SSS-BCFZY single cell achieved the highest peak power density (528.5 mW cm−2 at 800 °C), surpassing all the other SSS-based single cells. Therefore, the addition of NiO to the SSS electrolyte demonstrates the significant sintering and electrical properties of SSS, proving evidence for the potential commercial application of SSS electrolytes for PCFCs. [ABSTRACT FROM AUTHOR]

This work investigated the influence of microwave sintering on the BaCe 0.2 Zr 0.7 Y 0.1 O 3-δ phase, incorporating 2 mol% or 4 mol% NiO as sintering aid. X-ray diffraction analysis of perovskite phase detected a rhombohedral structure under both sintering heating rates (280 and 500 °C/min), also exhibiting the presence of a second phase deficient in Ba with Ni incorporated into the structure, replacing part of the Zr. Raman analysis indicated no distortions in the perovskite structure, independent of the rates and NiO concentrations. The efficacy of NiO addition as a sintering aid was demonstrated by high densification of the samples, exceeding 97 % relative density. Detailed analysis of structural, microstructural, and conductivity properties revealed that microwave sintering, particularly using a heating rate of 500 °C/min, yielded superior results compared to conventional sintering. The enhanced electrical response was attributed to a higher concentration of structural defects, oxygen vacancies, in the microwave-sintered samples, evidenced by the band at 630 cm−1 in the Raman spectrum. Among these, the BCZY sample with 2 mol% NiO, sintered under these conditions, stood out as the most promising, showcasing not only high density but also a uniform microstructure and appreciable electrical conductivity. [ABSTRACT FROM AUTHOR]

High-conducting and long-term stable proton-conducting electrolytes are of utmost importance. This study investigates the synthesis and characterization of BaCe 0.7 Zr 0.1 Cu x Y 0.2-x O 3-δ (BCZCu x Y; x = 0, 0.005, 0.01, 0.02, 0.05, and 0.1) electrolytes tailored for proton-conducting solid oxide fuel cells (SOFCs). Through Cu2+ doping at the B-site of BaCe 0.7 Zr 0.1 Y 0.2 O 3-δ (BCZY), a successful reduction of the sintering temperature to 1200 °C was achieved. BCZCu 0.02 Y exhibited a high relative density of approx. 98.1% at this temperature, but beyond 2 mol% Cu doping, the appearance of a BaCuO 2 secondary phase adversely impacted conductivity. The electronic properties of BCZY and BCZCu x Y are elucidated via partial density of states (PDOS) analysis, revealing optimized crystal structures and band gap reductions (from approx. 1.9 eV–1.1 eV) upon Cu doping. Notably, BCZCu 0.02 Y demonstrated a commendable conductivity, with values of 3.5 × 10−2 S. cm−1 in air and 4.8 × 10−2 S. cm−1 in a moist atmosphere at 750 °C. Remarkably, excellent electrochemical stability was observed in a moist hydrogen atmosphere for up to 450 h at 600 °C. Single cells incorporating BCZCu 0.02 Y electrolytes exhibited peak power densities of 380 mW/cm2 at 750 °C. The incorporation of 2 mol% Cu2+ in the BCZY lattice holds promise for achieving low-temperature sintering and high-performance proton-conducting SOFCs. [ABSTRACT FROM AUTHOR]

The non-uniform distributed pressure of impact wave is usually simplified into concentrated or uniform load equivalently in the optimization design of constrained layer damping structure. However, for the thin-walled structure, it becomes necessary to regard the load as a non-uniform distribution. In this paper, a topology optimization approach is proposed considering the blast load with non-uniform distribution, aiming to unveil its impact on optimization layouts and dynamic responses. Initially, the smoothed particle hydrodynamics (SPH) algorithm is used to obtain the blast pressure what are extracted and integrated into the optimization model. Subsequently, the relative density is regarded as design variable. The construction of material penalty model and the topology optimization model are based on polynomial interpolation scheme (PIS). The sensitivity of objective function is deduced employing an improved adjoint variable method (AVM) to fit the load forms, and the Newmark- β method is used to calculate the dynamic response. The optimization criterion (OC) is adopted to update the design variables. Finally, two numerical examples are used to exhibit the validity and accuracy of the presented methodology. The findings indicate that the distributed form, spread velocity, excited position and excited amplitude of the blast load all exert a notable influence on optimization results and dynamic response. These results underscore the valuable engineering application of this research and introduce a fresh perspective to the challenge of topology optimization under the blast case. [ABSTRACT FROM AUTHOR]

To clarify the effect of CuO on the arc erosion behavior of AgZrO 2 contact materials, the Ag-8 wt.%ZrO 2 contact materials without and with CuO addition were prepared by the combination of three-dimensional vibrating mixing and hot-pressing sintering, and the electrical contact tests were performed 5000 times on a JF04D electrical contact testing system. The effect of CuO additive on the arc erosion behavior of Ag-8 wt.%ZrO 2 contact material was studied, and the arc erosion mechanism was discussed as well. The results show that an appropriate CuO addition can significantly improve the hardness, electrical conductivity and arc erosion resistance of Ag-8 wt.%ZrO 2 contact material. At 0.5 wt%CuO, the optimal combination of relative density, hardness and electrical conductivity can be achieved, which are 99.48 %, 79.0 HV and 79.3 %IACS, respectively. Furthermore, the Ag-8 wt.%ZrO 2 contact material with 0.5 wt%CuO addition exhibits the lowest arc energy and shortest arc duration, least mass loss, and silver splashing as well as the formation of pores are also significantly inhibited, displaying excellent arc erosion resistance. This can be ascribed to the improved electrical conductivity and enhanced interface bonding together with CuO decomposition under high temperature arc. [ABSTRACT FROM AUTHOR]

In this study, the novelly designed Sr 0.5 Zr 2 (PO 4) 3 –Ce 0.5 Sm 0.5 PO 4 composite ceramics were utilized as nuclear waste form to simultaneously immobilize simulated fission products Sr and actinide nuclides. The phase transition mechanism, thermokinetics and densification behavior of Sr 0.5 Zr 2 (PO 4) 3 –Ce 0.5 Sm 0.5 PO 4 composite ceramics based on in-situ synthesis were systemically analyzed by XRD, in-situ XPS, TG-DSC, SEM and density measurements. The results demonstrate that the formation of Ce 0.5 Sm 0.5 PO 4 solid solution phase preceded that of Sr 0.5 Zr 2 (PO 4) 3 phase, of which there is a valence change of Ce from Ce4+ to Ce3+ before 1023 K. Additionally, as for the exothermic crystallization enthalpy, change of exothermic crystallization enthalpy and activation energy, the values of Sr 0.5 Zr 2 (PO 4) 3 and Ce 0.5 Sm 0.5 PO 4 phases in composite ceramics are 286.17 – 515.61 mJ, 19.11 – 35.38 J/g, 702.45 kJ/mol and 145.21 – 232.44 mJ, 9.26 – 15.44 J/g, 450.04 kJ/mol, respectively. It is then indicated that the formation of Ce 0.5 Sm 0.5 PO 4 phase is definitely more favorable than that of Sr 0.5 Zr 2 (PO 4) 3 phase. Simultaneously, the relative densities of Sr 0.5 Zr 2 (PO 4) 3 –Ce 0.5 Sm 0.5 PO 4 composite ceramics are more than 95 % when the sintering temperature exceeds 1273 K. [ABSTRACT FROM AUTHOR]

Al 2 O 3 -based ceramic tool materials synergistically reinforced by SiC whiskers (SiC w) and SiC particles (SiC p) were prepared via spark plasma sintering (SPS) technique. The densification behavior, sintering kinetics and optimal ratios of SiC w and SiC p on Al 2 O 3 -based ceramic tool materials were investigated. Results indicated that densification mainly occurred from 1200 to 1450 °C. Grain boundary sliding or grain boundary diffusion was the primary cause of densification at 1200–1350 °C. Whereas, dislocation climbing was the main densification mechanism at 1400–1450 °C. W25P5 sintered at 1450 °C had a large relative density, small grain size and the best mechanical properties with the fracture toughness of 7.35 ± 0.19 MPa m1/2, Vickers hardness of 21.79 ± 0.21 GPa, and relative density of 98.86 ± 0.15 %. The synergistic toughening mechanisms included crack deflection, whisker bridging and whisker pull-out. [ABSTRACT FROM AUTHOR]

There is an increasing demand for nonalcoholic wines owing to religious beliefs, responsible driving, harmful effects of alcohol, and strict alcohol regulatory measures. Alcohol removal methods, used for nonalcoholic wine production, have negative impact on flavour characteristics and consumer acceptance. This study seeks to determine the fermentation kinetics and physicochemical properties of nonalcoholic wine developed from cashew apple juice using cold fermentation in combination with special yeast. The extracted cashew apple must was inoculated with S. ludwigii and Z. rouxii yeast culture separately and allowed to ferment at 0°C–4°C for 7 days in a completely randomized design. The pH, total soluble solids (TSS), temperature, specific gravity, titratable, volatile, and nonvolatile acidities of the fermenting must and wine were determined using standard methods. All the yeast strains maintained comparable fermentation trends with respect to pH, TSS, specific gravity, volatile acidity, titratable acidity, and fixed acid, but with different alcohol yields of 0.89 and 0.68% for S. ludwigii and Z. rouxii, respectively. The wine produced using S. ludwigii had a lower reducing sugar (3.58 mg/L) and TSS (6.65°Brix) compared to Z. rouxii (6.23 mg/L and 7.65°Brix), respectively. However, no significant differences existed in pH, titratable acidity, specific gravity, alcohol content, and colour characteristics: brightness (L∗). The matured wine products recorded 0% alcohol content and had distinct appealing colours. The application of cold fermentation combined with special yeast in nonalcoholic wine production is promising and deserves more research to explore its full potential in meeting the increasing demand for nonalcoholic wines. [ABSTRACT FROM AUTHOR]

Additive manufacturing, notably laser powder bed fusion (LPBF), excels in producing complex geometries and is widely used in the automotive, aerospace, and naval industries. Laser powder bed fusion enables the creation of components with the required stiffness and strength at a lighter weight than traditional manufacturing methods. Aluminium alloys are particularly promising for laser powder bed fusion in the automotive and aerospace sectors. To enhance the effectiveness of laser powder bed fusion‐produced components, optimized process parameters must be designed for specific materials. This study investigates the influence of processing parameters, scan speed, scan strategy, and hatch space, on the relative density, surface roughness, and microhardness of AlSi12 samples fabricated by laser powder bed fusion. A Taguchi L27 orthogonal array was used to systematically analyze the effects of these parameters. A regression model was developed and evaluated through analysis of variance using signal‐to‐noise (S/N) ratios to identify optimal parameter values. Results indicated that the scan pattern significantly affects relative density, while hatch space impacts surface roughness and microhardness. Optimal solutions were obtained through multi‐objective optimization using the non‐dominated sorting genetic algorithm (NSGA‐II) and Pareto search algorithms. Experimental validation showed average errors of 0.483 % and 0.461 % for NSGA‐II and Pareto search algorithms, respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, the etching characteristics of InGaZnO4 (IGZO) thin films were systemically investigated in inductively coupled CH4/Ar plasmas with various gas ratios, bias voltages, and surface temperatures. The ion flux in the CH4/Ar plasmas was analyzed using bias power and voltage, whereas the relative densities of CH and H radicals were quantified through optical actinometry. The change in CH3 radical density was also estimated based on plasma kinetics analysis. The correlations between the plasma properties and IGZO etch rate were investigated. In CH4/Ar plasmas with CH4 ratios below 80%, the IGZO etch rate increases with a higher CH4 proportion, aligning with the ascending trend of CH3 radical density, which suggests that CH3 radical density acts as a limiting factor (radical‐limited regime). However, the IGZO etch rate decreases when the CH4 ratio exceeds 80%, corresponding to the reduction in ion flux, which indicates that ion flux becomes a limiting factor in this ion‐limited regime. The IGZO etch rate shows a linear relationship with bias voltage and follows the Arrhenius equation with varying surface temperature in plasmas without bias voltage. A spontaneous etch model was proposed based on these relationships. In this model, the IGZO etch rate depends on CH3 radical density and IGZO surface reactivity, where ion bombardment contributes more significantly to surface reactivity than high surface temperature. IGZO thin film was deposited on SiO2 during the fabrication of a 3D stacked ferroelectric field‐effect transistor (FeFET) memory device. The interaction between IGZO and SiO2 during CH4/Ar plasma processing was investigated using time‐of‐flight secondary ion mass spectrometry. The efficacy of removing IGZO atoms that had diffused into the SiO2 network was enhanced when subjected to plasma with a bias voltage, compared to the process without a bias voltage. However, exposure to CH4/Ar plasma resulted in a deeper diffusion of IGZO atoms into the SiO2 network, primarily attributed to ion bombardment rather than elevated surface temperature. A significant improvement in surface smoothness was achieved after IGZO and SiO2 etch by introducing BCl3 into the SiO2 etching chemistry. [ABSTRACT FROM AUTHOR]

A novel reactive sintering strategy using high‐entropy disilicide, B4C, and carbon as initial materials is developed to fabricate dense carbon fiber reinforced high‐entropy diboride (HEB)‐based composite (Cf/HEBs) at a relatively low temperature. The Cf/(V0.2Nb0.2Cr0.2Mo0.2W0.2)B2–SiC composite (Cf/HEB–SiC) successfully achieves nearly full densification (with a relative density of 99.2%) at 1800°C. The reactive damage of carbon fibers can be effectively restrained by preassemble carbon coating during the preparation process of the composite. Lower preparation temperature and effective coating protection contribute to the exertion of carbon fibers toughening capacity, consequently noticeably elevating the critical crack size (αcr) from 27.7 µm for HEB–SiC to 110.4 µm for Cf/HEB–SiC. The current work provides a feasible way to substantially upgrade the damage tolerance of HEB–SiC and can be extended to other HEBs‐based ceramics. [ABSTRACT FROM AUTHOR]

In the present work, WB2–SiC composite powders containing 20 vol.% of SiC were in situ synthesized by the boro/carbothermal reduction with WO3, SiO2, B4C, and carbon black as raw materials at 1400°C, 1500°C, and 1600°C, respectively. The as‐synthesized composite powders were then consolidated by spark plasma sintering (SPS) technique to obtain WB2–SiC composite bulk samples. The experimental results showed that the relative density of the WB2–SiC composite ceramic samples achieved in this study was higher than 97.5%. Also, electronic microscopy observations showed that SiO2 had reacted completely during the preparation process, and the SiC grains were homogenously embedded among the WB2 grains with the formation of a three‐dimensional structure. The Vickers hardness and fracture toughness values of the composite ceramic fabricated by powder heat treated at 1400°C were 24.6 ± 0.7 GPa and 5.4 ± 0.7 MPa·m1/2, respectively, which were the highest among three samples prepared in this study. [ABSTRACT FROM AUTHOR]

Coral reefs support an incredible abundance and diversity of fish species, with reef-associated fisheries providing important sources of income, food, and dietary micronutrients to millions of people across the tropics. However, the rapid degradation of the world's coral reefs and the decline in their biodiversity may limit their capacity to supply nutritious and affordable seafood while meeting conservation goals for sustainability. Here, we conduct a global-scale analysis of how the nutritional quality of reef fish assemblages (nutritional contribution to the recommended daily intake of calcium, iron, and zinc contained in an average 100 g fish on the reef) relates to key environmental, socioeconomic, and ecological conditions, including two key metrics of fish biodiversity. Our global analysis of more than 1,600 tropical reefs reveals that fish trophic composition is a more important driver of micronutrient concentrations than socioeconomic and environmental conditions. Specifically, micronutrient density increases as the relative biomass of herbivores and detritivores increases at lower overall biomass or under high human pressure. This suggests that the provision of essential micronutrients can be maintained or even increase where fish biomass decreases, reinforcing the need for policies that ensure sustainable fishing, and that these micronutrients are retained locally for nutrition. Furthermore, we found a negative association between micronutrient density and two metrics of fish biodiversity, revealing an important nutrition-biodiversity trade-off. Protecting reefs with high levels of biodiversity maintains key ecosystem functions, whereas sustainable fisheries management in locations with high micronutrient density could sustain the essential supply of micronutrients to coastal human communities. • Fish trophic composition is the most important driver of micronutrient density • Micronutrient density is negatively associated with fish biomass and diversity • Sustainable management remains essential to support nutritious reef fisheries Maire et al. explore how the nutrient quality of reef fish communities changes with environmental, socioeconomic, and ecological conditions, including fish biodiversity. A nutrition-biodiversity trade-off can exist and implies a new target for fisheries management that maximizes nutritional harvest without compromising efforts to reverse biodiversity loss. [ABSTRACT FROM AUTHOR]

The development of electrically active biomaterials, which create electrical cues on demand to foster cellular stimulation, remains a challenge. Here, we utilized a Field-assisted sintering approach to densify barium titanate and 45S5 bioactive glass to create a piezoelectric and potentially bioactive composite. By using Field-assisted sintering, we aimed to fabricate dense piezoelectric specimens, preserving a low degree of crystallization of the bioactive glass to keep bioactivity as high as possible. Therefore, we have varied the compositions of the materials and processed them at different sintering temperatures. This enabled us to produce dense test specimens in the 94 %–98 % relative density range. The samples were successfully polarized, and piezoelectric charge constants d 33 were determined for the composites. The content of bioactive glass and the sintering temperature influence the charge constant d 33. It is in the range of 0.8–3.4 pC/N for the composites, approximately in the order of magnitude assigned to natural tissues such as bone. X-ray diffraction was used to analyze the composition of the processed samples and to investigate the influence of an additional thermal post-treatment. Altogether, we established a process window for field-assisted sintering, allowing the fabrication of a piezoelectric and potentially bioactive biomaterial for tissue engineering. [ABSTRACT FROM AUTHOR]

Low-temperature ceramic fabrication techniques, which can reduce CO 2 emissions and energy consumption, are important. BaZrO 3 ceramics, which are conventionally sintered at over 1600 °C, were prepared at close to room temperature by a novel process called acid-base chemical densification (ABCD). BaZrO 3 ceramics could be fabricated by reacting a compact of ZrO 2 hydrous gel with a solution of Ba(OH) 2 ·8H 2 O at less than 100 °C. The densities of BaZrO 3 ceramics depended on the various ABCD process parameters. To obtain a higher density of BaZrO 3 ceramics, all the parameters were optimized simultaneously using machine learning. Three algorithms, Linear Regressor (LR), Random Forest (RF) regressor, and Light Gradient Boost Machine (LGBM), were compared for the prediction of BaZrO 3 density. The RF regressor predicted the relative densities of BaZrO 3 ceramics using the process parameters with high accuracy. From the results of the important features obtained from the RF model, the water content in the zirconia hydrous gel used as a precursor is important for the densification of BaZrO 3 in this process, although the reaction time and precursor density affected the densities in the ABCD process. In contrast, varying the reaction temperature in the chemical reaction between ZrO 2 hydrous gel and Ba(OH) 2 ·8H 2 O did not effectively improve the density in this study. By analyzing the top six important features in the RF model, we attempted to improve the accuracy of density prediction using the LR to predict the densities from the extrapolation data. Using an improved LR model, it was found that reducing the water content in the precursors is important for obtaining dense BaZrO 3 ceramics by the ABCD process. The water in the gel disturbs the densification because the volume of water molecules remains as pores in the pellets. [ABSTRACT FROM AUTHOR]

In the sintering of advanced ceramics, a digital twin consisted of a finite element model can predict the final shape and microstructure of a sintered ceramic. However, to minimise uncertainties, it is essential to continually update the mechanical properties in the digital twin using data collected from the manufacturing process. One promising approach for achieving this is through artificial neural networks (ANN). This study introduces a machine learning strategy to update the constitutive behaviour of advanced ceramics in finite element analysis of sintering deformation. A major challenge in implementing machine learning in material processing is the huge amount of data required by the training and validation of an ANN, which are often unavailable or incomplete in a real manufacturing process. This study demonstrates that the data requirement can be reduced by employing a two-step training technique. Firstly, the ANN is trained using a nonlinear constitutive law, which describes a general relationship between the strain rates and stresses. Subsequently, the weights and biases of the ANN are transferred for the retraining using limited experimental data for an actual ceramic. It is shown that such approach can successfully capture the nonlinear constitutive behaviour of fine-grained alumina without demanding for large amount of experimental data. A case study is provided, highlighting the feasibility of implementing the ANN in a commercial finite element package, to replace the constitutive law and predict the shrinkage and distortion of a sintering part. In particular, the sintered dumb-bell shape part, simulated using the retrained ANN, showed grain size and relative density that markedly different from those using the nonlinear constitutive law. It is important to note that the proposed methodology is generic and can be used to create ANNs to replace constitutive laws in finite element analysis in digital twins for a wide range of other engineering processes. [ABSTRACT FROM AUTHOR]

The rapid development of 5G and 6G technologies has led to an increased demand for microwave dielectrics ceramics. Microwave dielectrics ceramics with high Q value and low cost have attracted a lot of attention from researchers. Such as material sintered at relatively low temperature and cheap raw materials. Magnesium titanate (MgTiO3) is a material with excellent dielectric properties but requires high-temperature sintering. It is reported that substitution of Zn2+ for Mg2+ can lower sintering temperature and improve dielectric properties. Here, microwave dielectric properties and phase evolution of Zn-excess Mg0.95Zn0.05+xTiO3+x (x = 0, 0.025, 0.05, 0.075, 0.1) compositions were investigated. A moderate Zn-excess is found to promote formation of pure MgTiO3 phase with lower temperature. The composition with x = 0.05 sintered at 1300 °C possess optimal dielectric performance εr of 17.85, Q × f of 173,300 GHz (@11 GHz) and τf of − 52.04 ppm/°C with relative density of 97%. [ABSTRACT FROM AUTHOR]

Impact-induced defects in carbon fiber-reinforced polymers (CFRPs)-spanning from nanometer to macroscopic length scales-can be monitored using an aggregate of X-ray-based methods, but this is impractical in typical field conditions. We report on a low-velocity impacted CFRP, which is mapped using small- and wide-angle X-ray scattering and X-ray computed tomography, and employ machine learning for correlating material parameterizations derived from these techniques. The observed 1 μ m to 1 mm-sized defects are parameterized in terms of relative density and fiber orientation indicative of fiber failures (kink bands), and the nanometer sized defects in terms of crystal size and unit cell frustration. The 30 to 300 nm defects are parameterized by a power-law scattering decay, differentiating fractal-like behaviors. We find three spatial domains experimentally and by K-means Clustering: Domains of severe damage (with a visual dent), intact domains (without visual or measurable defects) and a transition domain (defects measurable by X-rays). How the parameters are correlated and how they overlap between the domains are discussed. All parameters are able to point to the detrimental fiber breakage in the severe damage domain, and scattering decay also in the transition domain, for example. How individual parameters determined from one experimental technique can be predicted from that of another is also described. [ABSTRACT FROM AUTHOR]

Synthesis and consolidation of (Zr,Ti)C were investigated in the present work. ZrC–TiC powder mixture was synthesized at 1650°C for 90 min by the carbothermal method. The prepared powder mixture was hot‐pressed at 1800 C for 60 min under a pressure of 40Mpa and then heat‐treated at 2100 C for 60 min. There were ZrC‐rich and TiC‐rich phases together with zirconium oxide phases in powder mixture and hot‐pressed samples, while there were no oxide phases in the heat‐treated sample and only ZrC‐rich and TiC‐rich phases were present in the sample. The FESEM image of the fracture surface of the samples shows that the porosity of the samples decreases with increasing temperature. Relative density, microhardness, and flexural strength increased from 93.8% to 98.6%, from 15.26 to 21.41 GPa, and from 185.02 to 220.69 MPa, respectively, with increasing temperatures from 1800 C to 2100 C. In contrast to these properties, the fracture toughness of the samples was reduced from 3.71 to 3.47 MPa·m1/2. The investigation of oxidation behavior also showed that oxidation is influenced by oxygen diffusion and exhibits nonlinear behavior as a function of time. With increasing oxidation temperature of hot‐pressed and heat‐treated samples from 600 to 1000°C, parabolic oxidation rate constants (kp) increased from .267 to 11.793 and from .367 to 10.993, respectively. [ABSTRACT FROM AUTHOR]

Chaetotaxy of the external pedipalp femur and distal ventral pedipalp movable finger was studied in 120 species, 69 genera and 17 families of scorpions. Setation was generally denser in the 'Buthus' group, a major arid-adapted buthid lineage distributed across Palearctic deserts. On the external femur, macrosetae formed a prominent cluster, the 'distal external macrosetal cluster' (DEMC); on the distal ventral movable finger they formed a dense patch, the 'distal ventral macrosetal cluster' (DVMC). In other buthids and non-buthids, the DEMC and DVMC were mostly absent, except in a few arid-adapted genera. Relative setation densities of DEMC and DVMC in different species depended strongly on size, being denser in larger species and sparser in smaller species, while absolute density varied only weakly with size (mean spacing of setae -200 μm in DEMC, -40 μm in DVMC). Ontogenetic variation followed similar trends. Multivariate morphometric analyses revealed taxonomic differences in setation patterns. The 'Buthus' group, other buthids, and non-buthids, were partially separable according to their spatial profiles of setation. In the 'Buthus' group, major genera were separable by spatial and density profiles of setation. In buthids, there were taxonomic differences in external femoral trichobothriotaxy. The 'Buthus' and Tityus' groups were largely separable by proximodistal positioning of trichobothrium e1. Relative setation densities of DEMC and DVMC were positively correlated, in that species with dense DEMCs also tended to have dense DVMCs. In the buthid Olivierus martensii, DEMC and DVMC were observed to brush the median ocelli during sponge-bathing. In all examined buthids, the DEMC was located where it would contact the ipsilateral median ocellus during femoral articulation. Both DEMC and DVMC may assist in the ocular grooming of desert buthids, by removing sand and dust from surfaces of the median ocelli. [ABSTRACT FROM AUTHOR]

The effect of SiC content (10 vol%, 20 vol% and 30 vol%) and sintering temperature (1800 °C, 1900 °C and 2000 °C) on the microstructure and mechanical properties of high entropy boride-silicon carbide (HEB-SiC) composites were systematically investigated in this work. The densification was gradually increased with the increase of SiC content and sintering temperature. More specially, the densification of HEB-30 vol% SiC composite obtained at 2000 °C was as high as 99.1 %. As for the mechanical properties, the dense HEB-30S-2000 composite possessed the highest fracture toughness (5.24 MPa m1/2) and Vickers hardness (28.5 GPa). The above significantly enhanced fracture toughness was closely pertained to the fracture modes adjusting. In details, after the addition of SiC, the branching and bridging of crack, the rupture of large SiC grain, and the deflection of crack existing near the HBE matrix and SiC particles jointly promote the improvement of fracture toughness. Besides, the Vickers hardness increased linearly with the relative density increasing. A simplified equation was established, which could effectually reflect the linear connection between the Vicker hardness and relative density (SiC content) of HEB-SiC composites. It will certainly play an important guiding role in the further development of HEB-SiC composites. [ABSTRACT FROM AUTHOR]

Calcite, as the thermodynamically stable phase of calcium carbonate, is a promising low-cost candidate as low- ε r microwave dielectric ceramics because of its large natural reserve and the strong covalency of C–O bond, while it is difficult to be densified due to the decomposition at about 627 °C. In the present work, calcite ceramics with the relative density of 87.8 % and low Qf value of 5,600 GHz were prepared by the room-temperature cold sintering, and the pressure-less sintering at 400–600 °C was conducted subsequently. The pressure-less sintering only increases the relative density slightly, while the microstructural evolution including the formation of uniform grains and significant grain growth were observed with increasing the sintering temperature, leading to a dramatic increase in Qf value. The best microwave dielectric properties with ε r = 7.60, Qf = 20,200 GHz, and τ f = −154 ppm/°C at around 12 GHz were obtained in the calcite ceramic sintered at 600 °C, indicating the applicable possibility of carbonate ceramics in microwave communications. [ABSTRACT FROM AUTHOR]

In order to solve the problem of signal delay, a novel low-K Ca 3 Cr 2 Ge 3 O 12 ceramic for 5G and millimeter-wave communication was prepared by a solid-state reaction method. XRD and Rietveld refinement results confirm that it belongs to the garnet structure with the Ia-3d space group. The shrinkage rate of the sample sintered at 1350 °C reached 11.9 %, and the relative density exceeded 94.3 %. Excellent microwave dielectric properties were obtained. The permittivity was 8.38, the quality factor was 23,107 GHz, and the temperature coefficient of resonant frequency was −43.57 ppm/°C. The relationship between the crystal structure and microwave dielectric properties of ceramics was further studied. The results show that lattice vibration, stacking fraction and bond strength have a great influence on the Q × f value of ceramics, and the bond valence parameter is the key factor affecting the temperature stability. In addition, the theoretical quality factor of the ceramic can reach ∼13,0000 GHz by far-infrared reflection spectroscopy, and the ceramic has great research potential. The development of Ca 3 Cr 2 Ge 3 O 12 ceramics and the study of microwave dielectric properties have filled the research gap of related systems. The excellent microwave dielectric properties indicate that it can be used as an alternative material for the preparation of components in the field of communication. [ABSTRACT FROM AUTHOR]

Two series of LiF-doped Li 4 CaSr(SiO 4) 2 (LCSS) ceramics with different LiF contents were synthesized by SSR and RS methods. The formation of single-phase LCSS + x wt% LiF (x = 0–4, SSR) (LCSSL 04) and LCSS + y wt% LiF (y = 0–8, RS) (LCSSF 08)ceramics with an orthorhombic structure (Pbcm space group) was confirmed by the Rietveld refinement of their XRD data. The addition of LiF improved the relative density and microwave dielectric properties of LCSS + x wt% LiF (0 < x ≤ 2, SSR) and LCSS + y wt% LiF (0 < y ≤ 3, RS). The LCSS +2 wt% LiF (SSR) ceramic exhibited good properties, presenting a dielectric permittivity (ε r) of 7.03, quality factor (Q × f) of 62,195 GHz (at 11.6 GHz), and temperature coefficient of resonant frequency (τ f) of −76 ppm/°C. Further, the LCSS +3 wt% LiF (RS) ceramic exhibited outstanding performances, with an ε r of 6.1, Q × f of 103,086 GHz (at 15.8 GHz), and τ f of −67 ppm/°C. The chemical compatibility with silver suggests that both of them are potential candidates for low temperature co-fired ceramic (LTCC) devices. [ABSTRACT FROM AUTHOR]

The TiC/Ni composites with different CeO2 or CeO2@Ni content are fabricated by pressureless reactive sintering, and the CeO2@Ni particles are prepared by electroless plating technique. The results show that the continuous Ni layer is prepared on CeO2 particles, leading to the decrease of contact angle between CeO2 and Ni from about 116° to 65°. The relative density of composites with 1 wt% CeO2 increases from 85.79% to 96.45% by Ni layer on CeO2 particles. The CeO2 or CeO2@Ni particles exhibit no obvious influence on the microstructure of composites, and Ce atoms of CeO2 diffuse into TiC particles during the reactive sintering process. The mass gain of composite decreases from 7.4709 to 4.9075 mg cm−2 by addition of 1 wt% CeO2@Ni. The Ce‐doped in NiO and TiO2 would restrict the inward diffusion of O atoms and outward diffusion of Ni atoms, resulting in the improvement of oxidation resistance of composite. With the increase of CeO2@Ni content from 0 to 1 wt%, the surface specific resistance of composite decreases from 3.16 to 0.56 Ω cm2 at 800 °C due to the thinner oxide scale and lower bandgap of TiO2 by Ce doping. [ABSTRACT FROM AUTHOR]

Herein, Mg1−xNixZrTa2O8 (x = 0, 0.1, 0.3, 0.5, 0.8, 1) ceramics are synthesized using a solid‐phase reaction method. Ni2+ replacing Mg2+ improves the drawback of high sintering temperature and poor temperature stability. The samples have a relative density above 95% at the optimal sintering temperature. The sintering temperature of Mg1−xNixZrTa2O8 reduces from 1475 to 1400 °C. And single‐phase Mg1−xNixZrTa2O8 ceramics with monoclinic wolframite structures are analyzed. According to the Rietveld refinement results, with the doping of Ni2+, the transformation of unit cell volume leads to the shift of the main peak in the X‐Ray diffraction pattern to a higher angle in 0 ≤ x ≤ 0.3 and a lower angle in 0.5 ≤ x ≤ 1. The εr of Mg1−xNixZrTa2O8 is comparable to MgZrTa2O8. At 1400 °C, the Q × f is increased from 10 598 GHz in the undoped sample to 43 041 GHz in Mg0.9Ni0.1ZrTa2O8 ceramic. The absolute values of τf of ceramic samples decrease with the excessive Ni2+. The desirable dielectric properties (εr = 20.79, Q × f = 43 041 GHz, τf = −33.04 ppm °C−1) are obtained at 1400 °C. Ni substitution is effective for MgZrTa2O8 ceramic to optimize densification temperature and retain the high Q × f value. [ABSTRACT FROM AUTHOR]

Barite is an inorganic mineral mainly constituted by barium sulfate (BaSO4) which finds applications across a variety of industries. Low quality barite can be beneficiated to meet high-purity requirement. Thus, in this work, we developed an optimum beneficiation process for upgrading barite-bearing ore from Azare in Bauchi State, Nigeria. The optimum condition for the beneficiation was established using response surface methodology (RSM) while the beneficiated barite was characterized using standard tests such as scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) and X-Ray diffraction (XRD). After beneficiation, the specific gravity and other properties, such as moisture content were determined and found within acceptable standards, indicating that impurities were removed. XRD structural patterns revealed highly crystalline peaks after treatment, while XRF analysis indicated BaSO4 as the primary component with reduced gangue impurities. The presence of barite in the samples was evidenced by the identified absorption peaks from FTIR analysis. Surface morphology characteristics revealed that the barite morphology changed significantly following beneficiation. The results of the beneficiation process showed that for the optimized process using RSM, the maximum yield of BaSO4 obtained was 99.78%. The properties of the barites obtained under the optimized conditions were all within the API standard. Accordingly, the beneficiated barite sample has prospective applications in drilling mud formulation, pharmaceuticals, medicine, rubber, paint, ceramics and glass industries. [ABSTRACT FROM AUTHOR]

AbstractThe determination of the pullout capacity of anchors has been a key point of offshore and onshore applications, considering factors such as the shape, size, penetration velocities, and pull-out velocities of the anchors. Multi-plate expandable anchors can be considered as an alternative that exhibits higher capacity compared to single plate anchors. While previous studies have demonstrated the influence of penetration velocity, there is a lack of research investigating the pullout capacity of multi-plate expandable anchors. In the present study, experimental tests were conducted to investigate the effect of various pull-out velocities. Different soil relative densities and the distance between anchors were examined in the laboratory tests. The study also employed two analytical methods—constant control volume and movement control volume—to investigate the results of pull-out velocity. In addition, the Discrete Element Method (DEM) was used to analyze the effect of particle shape on the results. In the experimental tests, the findings suggest that increasing the pull-out velocity from 10 to 30 mm/min improved the pullout capacity of anchors and the optimal distance between plate anchors was determined to be 1B. The DEM findings showed that the sharp-cornered shape had good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Background: Bacterial growth rate, commonly reported in terms of doubling time, is frequently determined by one of two techniques: either by measuring optical absorption of a growing culture or by taking samples at different times during their growth phase, diluting them, spreading them on agar plates, incubating them, and counting the colonies that form. Both techniques require measurements of multiple repeats, as well careful assessment of reproducibility and consistency. Existing literature using either technique gives a wide range of growth rate values for even the most extensively studied species of bacteria, such as Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. This work aims to apply several methods to reliably determine the growth rate of a recently identified species of Enterobacteriaceae, called Enterobacter sp. SM3, and to compare that rate with that of a well-known wildtype E. coli strain KP437. Results: We extend conventional optical density (OD) measurements to determine the growth rate of Enterobacter sp. SM3. To assess the reliability of this technique, we compare growth rates obtained by fitting the OD data to exponential growth, applying a relative density method, and measuring shifts in OD curves following set factors of dilution. The main source of error in applying the OD technique is due to the reliance on an exponential growth phase with a short span. With proper choice of parameter range, however, we show that these three methods yield consistent results. We also measured the SM3 division rate by counting colony-forming units (CFU) versus time, yielding results consistent with the OD measurements. In lysogeny broth at 37oC, SM3 divides every 21 ± 3 min, notably faster than the RP437 strain of E. coli, which divides every 29 ± 2 min. Conclusion: The main conclusion of this report is that conventional optical density (OD) measurements and the colony-forming units (CFU) method can yield consistent values of bacterial growth rate. However, to ensure the reproducibility and reliability of the measured growth rate of each bacterial strain, different methods ought to be applied in close comparison. The effort of checking for consistency among multiple techniques, as we have done in this study, is necessary to avoid reporting variable values of doubling time for particular species or strains of bacteria, as seen in the literature. [ABSTRACT FROM AUTHOR]

Practical Application The use of ultrasound for enhancing the extraction of sumac fruit oil was investigated to maximize the utilization of available sumac fruit resources. The optimal extraction parameters were determined using single‐factor trials and Box–Behnken design optimization and were found to be a liquid‐to‐material ratio of 13:1 mL/g, an ultrasound temperature of 47°C, and an ultrasound duration of 32 min. These yielded a 20.59% extraction rate of the oil. The ultrasonic‐assisted approach markedly increased the extraction rate and significantly reduced the extraction time when compared to classical Soxhlet extraction. The resulting sumac fruit oil had a brown‐yellow color with peroxide, acid, and iodine concentrations of 2.43 mg/g, 0.44 g/100 g, and 135 g/100 g, respectively, and relative density (d2020), and refractive index (20°C) values of 0.911, and 1.469, respectively. The primary fatty acids in the oil were stearic, linoleic, palmitic, linolenic, and oleic acids. With a 74.14% unsaturated fatty acid content, it has a high nutritional value as well as significant development and usage potential.This study demonstrates a highly efficient method for extracting vegetable oils and fats. It has the advantages of simple operation, low extraction temperature, short extraction time, high extraction rate, no damage to the material structure, excellent phusicai and chemical properties of the extracted vegetable oil, low cost, and the potential application in the food industry is crucial. [ABSTRACT FROM AUTHOR]

Today, there is a high demand and increasing trend for multifunctional composite materials and components due to the combination of a wide range of favorable properties. However, undesired deformation leading to delamination, curvature, cracks, or even complete fracture frequently occurs during the co‐sintering process of metal–ceramic laminates (MCLs). To solve these issues, experimental work highly relies on the time‐consuming trial‐and‐error principle. This work aims to develop a thermo‐mechanical‐metallurgical model capable of predicting the densification, deformation, and delamination of MCLs during the co‐sintering process. It is found that the developed model successfully considers the inhomogeneous relative density distribution and phase transformation of the steel tape. In addition, a thin interlayer formed by a mixed slurry in the MCLs is modeled as cohesive elements to simulate the delamination process. The developed model is systematically validated by the experimental measurements and observations in terms of densification, deformation, and delamination during the co‐sintering process of the investigated laminate variants. [ABSTRACT FROM AUTHOR]

A dual phase high‐entropy (Hf,Nb,Ta,Ti,Zr)C–(Hf,Nb,Ta,Ti,Zr)B2 ultra‐high temperature ceramic was synthesized using a single step boro‐carbothermal reduction route. The synthesized powder was densified by spark plasma sintering at 2000°C, resulting in complete solid solution formation and a relative density of ≈99%. The dual phase ceramic was 43 vol% high‐entropy carbide and 57 vol% high‐entropy boride. The grain sizes were 0.85 ± 0.34 µm for the carbide and 0.87 ± 0.33 µm for the boride with minimal residual oxide (0.2 vol%) detected in the microstructure. The resulting composition had a higher microhardness than the individual boride and carbide ceramics across the range of testing loads with maximum hardness of 47.5 ± 4 GPa at a load of 0.49N. The high hardness is attributed to the minimum residual oxide, submicron grains, favorable carbide‐to‐boride ratio, homogeneous metal distribution within the phases, uniform microstructure, and synergistic dual phase hardening. [ABSTRACT FROM AUTHOR]

The role of pressure, temperature, and particle size on cold sintering of ZnO has been investigated with a view to developing transparent thick films for device applications. Coarse ZnO (∼90–250 nm, cZnO) particles exhibited equiaxed grain growth under all conditions eventually achieving grain sizes of ∼ 0.5–1.0 µm at 300°C/375 MPa. In contrast, nano‐ZnO (40–80 nm, nZnO), exhibited grain growth along the c‐axis with a broader grain size distribution (0.5–4 µm) at higher temperatures and pressure (300°C/375 MPa) than cZnO. The broader grain size distribution is attributed to greater dissolution for nZnO compared with cZnO coupled with redistribution of Zn acetate/acetic acid into pores. ZnO continues to dissolve and reprecipitate within the pores throughout the densification process resulting in localized, larger grain sizes. In plane grain growth normal to the pressing direction was observed at and near the sample surface particularly in nZnO, which is attributed to constrained‐sintering. Some abnormal grain growth (10–20 µm) was also sporadically observed near or at the surface of nZnO (300°C/375 MPa) due to greater rates of reprecipitation as the transient solvent volatilizes adjacent to the die wall/plunger. Tape casting was used to fabricate single and multiple layers (≈30 µm) of ZnO on Kapton® to demonstrate the potential for device fabrication. Transparency was achieved by choosing cold sintering conditions (200°C/250 MPa) for nZnO that gave ∼95% relative density while restricting a majority of grain growth to <200 nm so that internal light scattering from grain boundaries was avoided. [ABSTRACT FROM AUTHOR]

Aim: Extracorporeal Shock Wave Lithotripsy (ESWL) is a commonly used method for the noninvasive treatment of kidney stones. However, achieving optimal treatment outcomes and minimizing potential damage to the kidney necessitates careful consideration for the total amount of energy utilized. This study aims to investigate whether urine pH and urine specific gravity have an impact on the total amount of energy applied during SWL. Patients and methods: Between January 2023 and December 2023, 129 patients with renal stones underwent SWL in our department using the Storz Medical Modulith Inline lithotripter. Stone-free rates, complications, and the impact of patient, urine, and stone characteristics on energy use were analyzed. Urine samples were analyzed for pH and specific gravity. Stone characteristics, including size, HU, and skin-to-stone distance, were recorded. The obtained data were evaluated regarding the possible relationship between the total energy amount (determined as a risk factor) and the age, BMI, urine pH, urine specific gravity, stone size, HU, and skin-to-stone distance by using the Pearson correlation coefficient. p-value of < 0.05 was considered statistically significant. Results: Evaluation of our findings revealed a negative linear relationship between total amount of energy used and the urine pH, indicating a decrease in the total energy amount as urine pH shifts towards alkaline values (p = 0.038; p < 0.05). However, no statistically significant relationship was observed between age, BMI, urine specific gravity, stone size, HU, and skin-to-stone distance and the total energy amount. Conclusions: Our findings demonstrated a significant relationship between urine pH and the total amount of energy applied during SWL sessions, suggesting the need for further prospective research to better understand the possible association between these two parameters. Such investigations could contribute to the development of more reasonable and effective strategies for kidney stone treatment in an attempt to minimize the potential kidney damage. [ABSTRACT FROM AUTHOR]

Highlights Developing sustainable composites for engineering applications is essential for minimizing environmental impacts and ensuring the long‐term viability of infrastructure and technological advancements. In this context, this work focuses on the manufacture and evaluation of the structural integrity of a sandwich structure composed of aluminum faces and egg‐box‐shaped, sisal fiber‐reinforced epoxy (SFE) or castor‐oil polyurethane (SFC‐O) composites. The sandwich panel is filled with a biobased foam and subjected to dynamic load (drop‐tower) test. For comparison, the base materials SFE and SFC‐O molded into the egg‐box‐shaped cores are also evaluated using Charpy impact tests to establish a potential correlation between their Charpy performance and the drop‐tower behavior of egg‐box sandwich structures. The findings reveal that SFC‐O laminates demonstrate superior Charpy impact resistance (~49%) compared to SFE laminates. Similarly, sandwich structures composed of egg‐box‐castor‐oil composite cores absorb approximately 42.5% more energy than those made with egg‐box‐epoxy cores. The impact behavior of the sandwich structures correlates directly with the impact resistance of the sisal fiber laminates. Overall, the results indicate that the castor‐oil polymer can effectively replace the epoxy polymer matrix phase, enhancing impact absorption and providing an environmentally correct and sustainable solution for fabricating sandwich panels. Castor‐oil polymer provides laminates with lower density relative to epoxy. Sisal‐castor‐oil‐based laminates possess higher impact resistance than those based on epoxy. Sisal‐castor‐oil‐based panels achieve higher absolute and specific drop‐tower impact properties. Panels subjected to drop‐tower impact tests reveal skin delamination, wrinkling and indentation. Debonding between the foam and egg‐box core is a typical failure mode for epoxy sandwich panels. [ABSTRACT FROM AUTHOR]

The two main competing theories proposed to explain the formation of massive (>10 M ⊙) stars—competitive accretion and monolithic core collapse—make different observable predictions for the environment of the massive stars during, and immediately after, their formation. Proponents of competitive accretion have long predicted that the most massive stars should have a different spatial distribution to lower-mass stars, through the stars being either mass segregated or being in areas of higher relative densities or sitting deeper in gravitational potential wells. We test these predictions by analyzing a suite of smoothed-particle hydrodynamics simulations where star clusters form massive stars via competitive accretion with and without feedback. We find that the most massive stars have higher relative densities, and sit in deeper potential wells, only in simulations in which feedback is not present. When feedback is included, only half of the simulations have the massive stars residing in deeper potential wells, and there are no other distinguishing signals in their spatial distributions. Intriguingly, in our simple models for monolithic core collapse, the massive stars may also end up in deeper potential wells because if massive cores fragment then the stars that form are also massive, and dominate their local environs. We find no robust diagnostic test in the spatial distributions of massive stars that can distinguish their formation mechanisms, and so other predictions for distinguishing between competitive accretion and monolithic collapse are required. [ABSTRACT FROM AUTHOR]

Microextrusion‐based additive manufacturing of zirconia‐based bioceramics is capable of fabricating design‐specific architectures with high mechanical strength properties and relative density. We developed a novel organic residue‐free binder system for zirconia paste printing (ZP2) with the shear‐thinning properties apropos to microextrusion‐based 3D printing. Based on thermogravimetric analysis, debinding protocol was established followed by high‐temperature heat treatment under four sintering conditions. Quantitative linear shrinkage (32.3%–42.7% ranging from in‐plane to vertical direction), density (83.3%–87.5%), and surface roughness (7.7–13.8 µm from the parallel to the perpendicular to the infill direction) as a factor of sintering conditions (1400°C–1500°C for 3–4 h) were analyzed. Whereas qualitative phase assemblage demonstrated “sintering condition independent” phase stability; grain growth and reduction in porosity were observed in the microstructure with increment in sintering temperature and hold time. Interestingly, at higher temperature and hold time, the compressive (46–72.4 MPa) and tensile strength (16.2–23.1 MPa) properties experienced a trade‐off between grain growth and reduction in porosity. The ZP2 scaffolds sintered at lower temperature and hold time qualified for the bone scaffold applications having interconnected porosities, biologically relevant surface roughness, and human bone mimicking mechanical properties. With a unique finite element analysis recipe, the mechanical behavior of the “life‐like” reconstructed computer aided design (CAD) geometries identical to real 3D‐printed‐sintered ZP2 scaffolds was quantitatively predicted. [ABSTRACT FROM AUTHOR]

Improving the efficiency of bifunctional electrocatalysts is a decisive challenge in the area of long‐lasting rechargeable zinc‐air batteries. Enhancing the catalysts' performance is crucial for advancing zinc‐air batteries. Transition‐metal oxides have emerged as promising non‐precious, noble‐metal‐free catalysts. Herein, a unique precursor directed approach is introduced for preparing a cobalt ferrite@nitrogen doped carbon nanohorns (CoFe2O4@N‐CNHs) nanohybrid catalyst in a single step annealing process involving stoichiometric amounts of single‐source cobalt and iron molecular precursors and carbon nanohorns (CNHs) under an argon/ammonia (Ar/NH3) atmosphere. This procedure enables a simultaneous CoFe2O4 ferrite synthesis and nitrogen functionalization of CNHs. The precious metal free nanohybrid CoFe2O4@N‐CNHs‐30% containing 30% of carbon presents an oxygen reduction reaction (ORR) half wave potential and onset potential comparable to the standard ORR catalyst 20% Pt/C. CoFe2O4@N‐CNHs‐30% also establishes superior oxygen evolution reaction (OER) performance with a low overpotential and a small Tafel slope than benchmark OER catalyst RuO2. Furthermore, the rechargeable zinc‐air battery with the CoFe2O4@N‐CNHs‐30% nanohybrid as air electrode demonstrates steadier and more durable charge–discharge cycles, and outstanding energy density relative to the state‐of‐the‐art 20% Pt/C‐RuO2 catalyst. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical properties and fatigue performance of Ti6Al4V cellular lattice materials (CLMs) featuring five distinct unit cell types (BCC‐Z, BCC, Octet, Truncated cuboctahedron [TCO], and Trabecular) at a relative density of 25%. Compression tests were conducted to assess static properties, including Young's modulus and yield strength. Subsequently, compression–compression fatigue tests (R = 0.1) were performed to evaluate fatigue behavior. Acoustic emission analysis was employed during static and fatigue tests to explore the potential for failure prediction. Results reveal that BCC‐Z and TCO exhibit slightly higher Young's moduli, surpassing 20 GPa, while BCC, Octet, and Trabecular display moduli ranging from 6 to 12 GPa. Regarding normalized fatigue behavior, BCC‐Z demonstrates superior fatigue resistance, followed by TCO. Notably, the acoustic emission parameters significantly correlate with the unit cell type. Lastly, a strong relationship between the initiation of failure and changes in acoustic emission parameters is observed, establishing a meaningful link between the static and fatigue curves and acoustic emission results. Highlights: Five different lattice topologies have been investigated under static and fatigue loading.BCC‐Z and TCO cell topologies have shown better mechanical performance comparatively.Mechanical response correlates with AE signals in both loading conditions.AE changes near the yielding and crack initiation for static and fatigue loads. [ABSTRACT FROM AUTHOR]

The objective of this research is to explore the scale effect on the mechanical properties of sheet‐based triply periodic minimal surface (TPMS) uniform lattice structures fabricated with PLA (polylactic acid) under quasi‐static loading conditions. The scale dependency was evaluated by two additional breakdown categories, namely, wall thickness effect and unit cell size effect. Deformation mechanisms and failure modes as well as mechanical properties including stiffness, yield strength, first peak stress, and energy absorption based on the categories of wall thickness, unit cell size, and scale were evaluated experimentally. The assessment of the scale effect involved considering the combined influence of wall thickness and unit cell size. In addition, numerical analysis was also performed to investigate the stress distributions and compare with the experimental results for certain geometries. Ultimately, the relation between the normalized mechanical properties and relative density is evaluated and categorized, which can be used as an indication for future design practices. Highlights: Scale, wall thickness, and unit cell size effect of lattice structures were studied.Relative density played a significant role in determining mechanical properties.Unit cell size to wall thickness ratio is critical for different failure mechanisms.Normalized mechanical properties were evaluated for the future design. [ABSTRACT FROM AUTHOR]