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Aluminum powder particle size (D50) is quite important for how to improve the energy release level and formulation design of aluminized explosives. In this paper, four experimental samples of CL-20-based aluminized explosives with aluminum powder particle sizes including 2, 13, 24, and 43 μm were designed. The experiments were carried out through an underwater explosion tank and compared with explosives containing lithium fluoride of the same particle size. The results show that the burning of aluminum powder promoted the shock wave propagation and bubble expansion. Aluminized explosives have a lower and then higher decay rate than lithium fluoride-containing explosives. For the experimental range of aluminum powder particle sizes, with an increase in D50, the peak shock wave pressure first increased and then decreased, reaching the maximum at 24 μm; the shock wave and loss energy gradually increased, while the bubble energy, energy utilization, and underwater explosion total energy all gradually decreased. To a certain degree, the energy output structure can be regulated by adjusting the D50 under the premise of constant total energy of explosives. The experimental results improve our understanding of how D50 affects the underwater explosion parameters of aluminized explosives, which is of great significance for improving their energy utilization. [ABSTRACT FROM AUTHOR]

We implanted Fe+ ions in nanodiamond (ND) powder containing negatively charged nitrogen-vacancy (NV−) centers and studied their Raman spectra and optically detected magnetic resonance (ODMR) in various applied magnetic fields with green light (532 nm) excitation. In Raman spectra, we observed a blue shift of the NV− peak associated with the conversion of the electronic sp3 configuration to the disordered sp2 one typical for the carbon/graphite structure. In the ODMR spectra, we observed a red shift of the resonance position caused by local heating by an absorptive environment that recovers after annealing. To reveal the red shift mechanism in ODMR, we created a controlled absorptive environment around ND by adding iron-based Fe2O3 and graphitic sp2 powders to the ND suspension. This admixture caused a substantial increase in the observed shift proportional to the applied laser power, corresponding to an increase in the local temperature by 150–180 K. This surprisingly large shift is absent in non-irradiated NV-ND powders, is associated only with the modification of the local temperature by the absorptive environment of NV-NDs, and can be studied using ODMR signals of NV−. [ABSTRACT FROM AUTHOR]

Laser-based powder bed fusion (L-PBF) has become the de facto choice for metal additive manufacturing (AM) processes. Even after considerable research investments, components manufactured using L-PBF lack consistency in their quality. Realizing the crucial role of the melt pool in controlling the final build quality, we predict the morphology of the melt pool directly from the build commands in an L-PBF process. We leverage machine learning techniques to predict quantitative attributes like the size as well as qualitative attributes like the shape of the melt pool. The area of the melt pool is predicted using an LSTM network. The outlined LSTM-based approach estimates the area with $ 90.7\% $ 90.7 % accuracy. The shape is inferred by synthesising the images of the melt pool by using a Melt Pool Generative Adversarial Network (MP-GAN). The synthetic images attain a structural similarity score of 0.91. The precision and accuracy of the results showcase the efficacy of the outlined approach and pave the way for real-time monitoring and control of the melt pool to build products with consistently better quality. [ABSTRACT FROM AUTHOR]

A novel chiroptical sensing technique was recently introduced that utilized the helical phase of the structured light as a chiral reagent instead of polarization of light to differentiate enantiopure chiral liquids. The unique advantage of this non-resonant, nonlinear technique is that the chiral signal can be scaled and tuned. In this paper, we extend this technique to enantiopure powders of alanine and camphor by dissolving them in solvents of varying concentrations. We show the differential absorbance of helical light to be an order of magnitude higher relative to conventional resonant linear techniques and is comparable to nonlinear techniques that use circularly polarized light. The origin of helicity dependent absorption is discussed in terms of induced multipole moments in nonlinear light–matter interaction. These results opens up new opportunities in using helical light as a primary chiral reagent in nonlinear spectroscopic techniques. [ABSTRACT FROM AUTHOR]

A novel (MoCrVMn) 2 FeB 2 based high-entropy cermets were prepared by two-steps method and the microstructure and mechanical properties were investigated. The single-phase (MoCrVMn) 2 FeB 2 powders were synthesized at 1400 °C for 2 h, and subsequently the (MoCrVMn) 2 FeB 2 based high-entropy cermets were prepared via pressureless sintering technique. The results revealed that the phase evolution was as follows: (Mo, Cr, V, Mn, Fe, B) → (Fe 2 B, V 2 B 3 , MoB) → ((FeVMn) 2 B, (FeVMnCr) 2 B, Mo 2 FeB 2) → (MoCrVMn) 2 FeB 2. The (MoCrVMn) 2 FeB 2 based high-entropy cermets sintered at 1250 °C showed good denseness and the ceramic phases were uniformly distributed in the metal bond, with the optimal mechanical properties of hardness 1355 HV 30 and fracture toughness 19.09 MPa m1/2. With the increase of temperature, the hardness increased first and then decreased, and the fracture toughness was basically unchanged first and then increased, and then decreased. This study provides a new route to further optimize the performance of Mo 2 FeB 2 based cermets. [ABSTRACT FROM AUTHOR]

The controllable α/β ratio of Si 3 N 4 powder was synthesized using tetraethyl orthosilicate (TEOS), glucose, MgCl 2 and YCl 3 ·6H 2 O by sol-gel assisted carbothermal reduction and nitridation (CRN). This study aimed to investigate the impact of various parameters, including a H 2 O/TEOS mol ratio of the sol, a C/Si mol ratio, sintering aids, and the temperature of CRN on the phase transformation of α-Si 3 N 4. The results demonstrated that the H 2 O/TEOS ratio significantly influenced the relative content of α and β phase in Si 3 N 4 by changing the morphological characteristics of SiO 2. When the H 2 O/TEOS ratio was 100, β-Si 3 N 4 powder with an approximate β content over 88 wt% was synthesized at 1500 °C. This remarkable phase transformation was likely facilitated by the eutectic liquid phase consisting of MgSiO 3 /Mg 2 SiO 4. The SEM image revealed rod-like whiskers with a length around 1.4 μm for the β-Si 3 N 4 grains. Due to the presence of liquid phase, the synthesis of spherical-like α-Si 3 N 4 nano-powder with an α-phase content of 91 wt% was achieved at a lower temperature of 1450 °C, with an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The size of the particles was about 70 nm due to the reduced reaction temperature. Furthermore, without the addition of any sintering aids or Si 3 N 4 seeds, high purity α-Si 3 N 4 with an α phase content approaching 96 wt% could be synthesized at 1500 °C, using an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The resulting α-Si 3 N 4 powder exhibited an extremely regular hexagonal prism shape with a length of approximately 2 μm. [Display omitted] [ABSTRACT FROM AUTHOR]

As one of the main waste streams of the manufacturing process of solid oxide cells (SOCs), scrap half-cells - discarded before the deposition of the barrier layer and the air electrode - imply the loss of significant quantities of ceramic composite material containing critical and hazardous elements, namely yttria-stabilized zirconia (YSZ) and NiO. These materials represent more than 90 wt% of an entire anode-supported cell. In this contribution, scrap half-cells were fragmented and subjected to three subsequent milling and sieving (below 25 μm) steps to recover composite NiO-YSZ powders with the appropriate specifications for reuse in SOC manufacturing. The overall characterization in terms of specific surface area, particle size distribution and crystalline phase retention confirmed the suitability of the recovered powders. Half-cells were manufactured including 30 wt% of recovered NiO-YSZ composite powders in their fuel electrode support, produced via tape-casting in combination with 70 wt% of virgin materials. The obtained cells were morphologically, mechanically and electrochemically tested and compared against standard cells constituted by 100 wt% of virgin materials. The electrochemical characterization highlighted 0.68 A cm−2 for the standard and recycled cells, at 600 °C and 0.7 V, while at 650 °C and same voltage both cells measured 1.12 A cm−2. This demonstrates the feasibility of recovering scrap SOCs through the presented method. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the structural, magnetic, and blood compatibility properties of Sr2+ substituted for Cu2+ in Cu 1−x Sr x Fe 2 O 4 (x = 0.0 to 1 with a 0.25 increment) nanoparticles synthesized via the sol-gel auto-combustion technique. Regardless of the substitution rate, the sol-gel auto-combustion method consistently yields powders with sizes ranging from 20 to 40 nm. The specific surface area of the produced powders is determined as 12 m2/g. X-ray diffraction analysis reveals that CuFe 2 O 4 exhibits a singular phase; however, as the Sr2+ ion substitution increases, the emergence of various secondary phases becomes apparent, with their proportions increasing with the substitution rate. The magnetic characteristics of the synthesized powders exhibit variations in magnetization, correlating with the distribution of cations in the sublattice points. Coercivities are influenced by both anisotropy and secondary phases. Saturation magnetization decreases from 31.3 (CuFe 2 O 4) to 7.6 (SrFe 2 O 4) emu/g with Sr replacement. The lowest observed coercivity is 429.5 Oe in powders prepared with CuFe 2 O 4 composition, while the highest is measured at 583.8 Oe in nanopowders prepared with Cu 0.5 Sr 0.5 Fe 2 O 4 composition. Moreover, blood compatibility experiments indicate significantly low hemolysis ratios for Cu 1−x Sr x Fe 2 O 4 nanoparticles. Additionally, all examined samples exhibit an increase in Soret band intensity compared to the negative control test, suggesting potential biocompatibility. [ABSTRACT FROM AUTHOR]

Currently, the lattice oxygen is the key factor affecting the thermal conductivity of AlN ceramics. In this paper, three methods are proposed to limit lattice oxygen, namely reducing the original powder oxygen content, changing the debinding atmosphere, and extending the sintering time. The results show that the low powder oxygen content and protective debinding atmosphere alter the carbon and oxygen content, and further promote the formation of the Y 4 Al 2 O 9 (YAM) phase. The generated YAM phase can effectively reduce the lattice oxygen in terms of thermodynamics. Prolonged high temperatures can provide kinetic conditions to reduce the lattice oxygen to 0.0343 wt%. In addition, morphological changes of the phase at the grain edges and their influence on the mechanical properties were noted. Finally, AlN ceramics with a thermal conductivity of 220 W m−1 K−1 and a flexural strength of 340 MPa were obtained. This study can provide a valuable reference for the industrial production of AlN ceramics. [ABSTRACT FROM AUTHOR]

Two MOX powders containing 11 mol% Pu/(U+Pu) have been synthesized using the freeze granulation or dry-cogrinding routes. The sintering behaviour of green compacts has been investigated up to 1700 °C in an Ar/4.3 vol% H 2 humidified with 1200 vpm H 2 O. The evolution of the sintering trajectory (grain size as a function of relative density) is identical up to approximately 94% relative density. Above this value, grain growth becomes significant in compacts made with the powder obtained by freeze granulation and densification becomes more modest. As for it, the sintering trajectory relating to the compacts shaped from the co-grinded powder continues up to approximately 97.5% relative density, without remarkable grain growth. Beyond this value, grain growth occurs and densification slows down. It has also been shown that the plutonium distribution is more homogeneous in the case of a sample sintered from the powder obtained by freeze-granulation (relative density around 97–99%). [ABSTRACT FROM AUTHOR]

Alumina-yttrium aluminum garnet (YAG)-zirconia composites are often produced by the melt solidification method. In the present study, we investigated the fabrication of α-Al 2 O 3 /Y 3 Al 5 O 12 (YAG)/ZrO 2 composite by Spark Plasma Sintering (SPS) of powders synthesized by Pechini's sol-gel method. The ternary composites with homogenous microstructure and high density were produced by SPS at 1300 °C for 15 min. The addition of ZrO 2 promoted the sintering of composites, resulting in a higher density and, in turn, higher hardness. A change in the indentation fracture behavior as the result of ZrO 2 addition was observed. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) ceramic stands as a critical material in the realm of high-performance engineering ceramics. However, Crafting SiC ceramics with intricate structures and superior mechanical properties presents notable challenges in shaping, sintering, and processing. Binder jetting (BJ) additive manufacturing has the outstanding advantages of high forming efficiency and no thermal deformation, especially suitable for printing complex structure SiC components.; however, BJ printed green bodies often exhibit low density, resulting in high residual silicon content and diminished strength of the final components. In this work, we introduce a novel strategy to fabricate high-strength SiC components with complex geometries by improving the density of printed SiC green bodies. This method involves modifying the morphology of SiC powder through the molten salt method to increase the density of BJ 3D printed green bodies from 1.24 ± 0.13 g/cm³ to 2.01 ± 0.03 g/cm³, followed by a reactive melt infiltration process. The resulting RB-SiC ceramics display exceptional flexural strength, averaging 280.60 ± 33.05 MPa, and an elastic modulus of 294.67 ± 4.90 GPa. These values represent some of the highest for flexural strength and elastic modulus reported among 3D-printed SiC composites. With its robust mechanical performance and streamlined fabrication process, this strategy holds substantial promise for the production of structural SiC ceramics. [ABSTRACT FROM AUTHOR]

Engineering new chalcogenide solids improves the desired functionality of the materials and may open the way for new applications. Here we discuss the preparation of As x S 100−x amorphous thin films modified with WS 3 by the sol–gel method. We show that the formation of homogeneous, transparent, and stable n-propylamine-based solutions by mixing 0.02M As x S 100−x and 0.02M (NH 4) 2 WS 4 solutions is feasible for the As content in the chalcogenide glass precursor x ≤ 25 at.%. Above this limit, rapid and massive precipitation occurs in the solutions. We further demonstrate the preparation of amorphous thin films along the pseudo-binary AsS 3 - WS 3 tie-line and provide information about the role of WS 3 on optical properties and the structure of tungsten-based chalcogenide thin films. Due to a significant etching contrast between annealed AsS 3 − WS 3 thin films at 70 and 240 ∘ C , we propose tungsten-based chalcogenide thin films as a suitable platform for application in wet-lithography. [Display omitted] • Homogeneous, transparent, and stable solutions by mixing As x S 100−x and (NH 4) 2 WS 4 solutions for x ≤ 25 at.%. • The WS 3 content increases the thermal stability of prepared thin films. • Optically transparent amorphous AsS 3 − WS 3 thin films up to a molar ratio of 1:3. • As WS 3 increases, the absorption edge is red-shifted. • The chemical resistance decreases to amine-based solutions with increasing WS 3 content. [ABSTRACT FROM AUTHOR]

This study investigates the physical characteristics of un- and Mn-doped SnS nanoparticles (NPs) synthesized through a co-precipitation method. The undoped SnS is referred to as Mn 0, while Mn 1, Mn 2, and Mn 3 samples are obtained by incorporating 1, 3, and 6 mL of Mn-dopant solution, respectively. Elemental analysis is done by means of energy-dispersive X-ray spectroscopy (EDX), confirming successful Mn incorporation into the SnS lattice. X-ray diffraction (XRD) studies validate the formation of the SnS phase with a preferred orientation at the (040) plane for all samples. The crystallite size (D) of SnS NPs initially increases and then decreases after Mn-doping, confirmed by transmission electron microscopy (TEM) images. Field emission scanning electron microscopy (FESEM) images exhibit grain-shaped morphology with sizes ranging from 23 to 36 nm for all samples. The reduction in bandgap energy (E g) upon Mn-doping is attributed to variations in grain size and the formation of impurity levels within the SnS band gap. Mott-Schottky analysis showed p -type conductivity for all samples. The semiconductor parameters of SnS, such as the acceptor concentration (N A) and the density of states (N V), improved after Mn-doping. Current-voltage (I – V) curves revealed that the conductivity and mobility of SnS after Mn-doping initially declined for Mn 1 and Mn 2 samples and then improved for the Mn 3 sample. Electrochemical impedance spectroscopy (EIS) results align with the I – V findings. Consequently, it can be concluded that Mn-doping leads to enhancements in optoelectronic properties of SnS. [ABSTRACT FROM AUTHOR]

Plate-like grain toughening is an effective approach to enhance the toughness of ceramics. Herein, we propose a novel method to prepare platelet-toughened Al 2 O 3 /ZrO 2 ceramics by pressureless sintering without any additives. The Al 2 O 3 /ZrO 2 powder was prepared through combustion synthesis assisted by rapid water cooling. The synthesis process involved ultra-high temperatures and a rapid cooling rate, leading to the formation of Al-Zr-Y oxide solid solution with γ-Al 2 O 3 or t-ZrO 2 structure in the powders. The surface of the powder after being acid etched or annealed was investigated. The results indicated that the solid solution with γ-Al 2 O 3 structure exhibited a dendrite morphology, which could develop into plate-like Al 2 O 3 grains during annealing or pressureless sintering. Platelets can effectively improve toughness by inducing crack deflection. Furthermore, numerous ZrO 2 nanoparticles precipitated from the solid solution, which also contributed to the enhancement of mechanical properties. Consequently, the toughness and hardness of the ceramic could reach up to 10.76 MPa m0.5 and 15.5 GPa, respectively. Additionally, this method could be applied to fabricate platelet-toughened Al 2 O 3 /ZrO 2 ceramics with a wide range of Al 2 O 3 contents (60 wt%∼80 wt%), thereby catering to a wide range of industrial applications. [ABSTRACT FROM AUTHOR]

The article introduces a novel roasting technique under a dynamic magnetic field (RDMF) that enables the rapid synthesis of MnB crystals, producing bulk and powder forms within seconds.

The effects of two cokes with different reactivity on the lump ore's metallurgical properties and coke's solution loss are investigated under the high‐temperature load reduction. The work used an improved test device for softening‐melting and dropping characteristics of iron ores in both CO2 and CO2H2O atmospheres. The deterioration behavior of highly reactive cokes is expounded under hydrogen‐rich conditions. High‐reactivity cokes under hydrogen‐rich conditions are more favorable for enhancing the breathability of charge and the penetration of the coke layer. However, it increased the thickness of the softening zone. High‐reactivity cokes had obvious internal and external reaction gradients. The solution loss reaction mostly occurred on the surface, with selectivity. The longitudinal stacking height, layer number, and order degree in the carbon structure decreases after the reaction. The carbon‐structure difference weakens between the shell and core. The enhancement of coke's reactivity, however, results in the significant loss of coke powders on its surface. Unreduced FeO and refractory Fe2SiO4 are more likely to appear in the droplets, which is not conducive to the reduction of Fe and the generation of slag crust in the furnace. The difficulty in separating lump ores and cokes is aggravated, and more iron‐containing charge remain in the furnace. [ABSTRACT FROM AUTHOR]

Designing multifunctional materials that mimic the light‐dark decoupling of natural photosynthesis is a key challenge in the field of energy conversion. Herein, we introduce MnBr‐253, a precious metal‐free metal–organic framework (MOF) built on Al nodes, bipyridine linkers and MnBr(CO)3(bipyridine) complexes. Upon irradiation, MnBr‐253 colloids demonstrate an electron photocharging capacity of ~42 C ⋅ g−1MOF, with state‐of‐the‐art photocharging rate (1.28 C ⋅ s−1 ⋅ g−1MOF) and incident photon‐to‐electron conversion efficiency of ~9.4 % at 450 nm. Spectroscopic and computational studies support effective electron accumulation at the Mn complex while high porosity and Mn loading account for the notable electron storage performance. The charged MnBr‐253 powders were successfully applied for hydrogen evolution under dark conditions thus emulating the light‐decoupled reactivity of photosynthesis. [ABSTRACT FROM AUTHOR]

To facilitate future pasteurization experiments utilizing microwave energy, the dielectric properties of five dried fruits — almond (Prunus dulcis), cashew nut (Anacardium occidentale), pistachio (Pistacia vera), peanut (Arachis hypogea L.) and walnut (Juglans regia) were investigated at room temperature (28∘C). Samples were taken in powder form to investigate the effect of increased surface-to-volume ratio on their dielectric properties, as applicable in the case of nanomaterials. The measurements were conducted at four different frequencies (3.30, 7.50, 9.30and 14.70GHz) in the microwave spectrum by using the two-point method and a MATLAB program was used for solving the transcendental equation to obtain values of dielectric constant and loss factor. The findings revealed a decreasing trend in the values of dielectric constant of the five dried fruits as the frequency increased. However, no consistent trend was observed for the dielectric loss factor of the fruits with increasing frequency. Further, the penetration depth of electromagnetic waves in all the five dry fruit samples was observed to decrease as the frequency increased. On comparing results for dielectric parameters of dry fruits in powder form with those of whole fruit kernels, no definite trends are observed for ε′ and ε″, but the penetration depth is found to decrease when the sample is taken in powder form. [ABSTRACT FROM AUTHOR]

Core–shell structural B 4 C@TiB 2 composite powders were synthesized via the molten salt method using micron-sized B 4 C and TiH 2 powders as raw materials. Furthermore, a SiC composite ceramic with B 4 C@TiB 2 core–shell structural units as the toughening phase was prepared by spark plasma sintering using SiC powder and the obtained B 4 C@TiB 2 composite powder as starting powders. The effects of calcination temperature and raw material ratio on the phase compositions and microstructure of the B 4 C@TiB 2 composite powders were studied, and the synthesis mechanism of the B 4 C@TiB 2 composite powder was explored. The formation mechanism of B 4 C@TiB 2 core–shell toughening units inside the SiC matrix was investigated, and the toughening mechanism of the SiC–B 4 C@TiB 2 composite ceramic was discussed. Results show that the B 4 C@TiB 2 core–shell units in the SiC matrix can induce a complex crack propagation mode and consume abundant crack propagation energy. Therefore, a high fracture toughness of 6.47 ± 0.32 MPa m1/2 is realized for the SiC–B 4 C@TiB 2 composite ceramics. [ABSTRACT FROM AUTHOR]

By pre-milling in glucose aqueous solution, γ-Al 2 O 3 particles were uniformly mixed with carbon via hydrothermal treatment technique. Then, directly heating the γ-Al 2 O 3 /C precursor at 50 °C/min to 1775 °C for 15–30 min in N 2 , single phase AlON powder was fast obtained through one-step carbothermal reduction and nitridation (CRN). By approaching the evolution of phase assemblages and morphology during heating and dwelling, the one-step fast CRN mechanism for preparing fine AlON powder was revealed. The carbon around γ-Al 2 O 3 particles delayed the phase transformation of Al 2 O 3 from γ phase to α one. The undesired particle aggregation and growth before formation of AlON was also auxiliarily inhibited by swiftly achieving AlON formation temperature via high heating speed. Further elevating synthesis temperature enabled high reaction kinetics to boost the speed of AlON formation. By these ways, CRN reactions were quickly completed to fast obtain pure AlON powder with small primary particles due to limited particle aggregation and growth. The as-prepared fine AlON powder was easy to be ball-milled to prepare highly transparent AlON ceramics by pressureless sintering. [ABSTRACT FROM AUTHOR]

The potential of HfO 2 as a memory semiconductor material with ferroelectric properties in thin-film deposition has been recently analyzed. In this study, the preparation, composition, and physical properties of Al-doped hafnium oxides were analyzed. Hf x Al (1- x) O y (HAO) [ x = 0.33, 0.5, and 0.67] powders were prepared by controlling the ratio of Hf to Al and using ball milling. The HAO powder was calcined at 1000 °C in a furnace and then sintered in a temperature range of 1000–1600 °C by a solid-state reaction method to fabricate high-quality targets with high densities. The density and crystal size increased with the sintering temperature. The 1600-°C Hf 0.67 Al 0.33 O y target was optimal for thin-film deposition. In addition, the target properties were affected by an increase in the HfO 2 content x. The crystal structures and sizes, surface free energies, contact angles, and band gaps of the HAOs were evaluated to analyze their potential as high- k dielectric materials. HAO is a promising high- k dielectric and memory material, valuable for further studies on ferroelectric gate oxide materials. This study contributes to the increasing number of studies on the ferroelectricity of HfO 2 thin films and provides a fundamental understanding of this material and its potential for novel device applications. [ABSTRACT FROM AUTHOR]

Background: White spot lesions are a widespread undesirable effect, especially prevalent during fixed orthodontic treatments. The study compared the in vitro enamel remineralization potential of undemineralized dentin matrix (UDD) versus chicken eggshell powder (CESP) for artificially induced enamel lesions. Methods: 100 caries-free and sound maxillary premolars were randomly divided into four groups each contain 25 teeth: Group I (Baseline): No treatment was done to the enamel surface. Group II (Negative control): The enamel surface of the teeth underwent demineralization using demineralizing solution to create artificial carious lesions then kept in artificial saliva. Group III (CESP treated): After demineralizing the tooth surface, the teeth have been suspended in the CESP remineralizing solution. Group IV (UDD treated): After enamel demineralization, the teeth were suspended in UDD remineralizing solution. The remineralization potential was assessed by Vickers microhardness testing, scanning electron microscopic examination (SEM), and energy dispersive X-ray (EDX). Results: The current study demonstrated an increase in the mean microhardness of CESP and UDD-treated groups; however, It was nearer to the baseline level in the UDD group. SEM imaging revealed greater enamel remineralization in the UDD group compared to the remaining groups. The UDD group disclosed complete coverage for the prismatic enamel compared to the CESP group, which revealed a partially remineralized enamel surface. Interestingly, the Ca/P ratio increased significantly in the CESP group compared to the negative control group. In contrast, a higher significant increase in the mean Ca/P ratios was recorded in the UDD group compared to the test groups. Conclusion: biomimetic UDD and CESP powder should be utilized to treat enamel early carious lesions. However, UDD demonstrated the most significant remineralization potential. [ABSTRACT FROM AUTHOR]

Summary The consumer is looking for foods that can satisfy the need to combine nutrition and well‐being, not only balanced in their composition but also endowed with properties that can improve, or at least maintain, a good state of health. The study aims to enrich the short‐crust pastry with raspberry powder, as a base for breakfast biscuits, increasing its antioxidant properties. Optimising the extent of integration with raspberry powder helped avoid interference with the cross‐linking process of the gluten mesh. The reformulation of shortbread cookies was compared with that of non‐enriched biscuits to define chemical composition, antioxidant potential, and sensory profile. A consumer test helped to evaluate the acceptability of the new formulations. The results indicate that the integration with the optimal identified percentage of raspberry powder, by‐products of juice production, represents an excellent matrix to increase the health properties of shortbread cookies, improving functionality and sensory acceptability. [ABSTRACT FROM AUTHOR]

The reconstruction of local electronic states in Pt-O x is an effective strategy for balancing charge distribution and enhancing the intrinsic activity of noble metals. This study presents the use of highly porous and oxygen-rich activated bluecoke powders as a desirable carbon support, and regulates Pt-O x bonds by incorporating the Fe as transition metal, leading to the development of an efficient bluecoke-based electrocatalyst characterized (Fe/Pt–O@MKABC) by exceptionally low Pt loading. The loading amount of Pt in Fe/Pt–O@MKABC is only 0.98 wt%, which is less than the 5% reported for commercial Pt/C catalyst, yet its hydrogen evolution performance is comparable. The developed catalyst presents exciting catalytic ability with overpotential of only 17 mV at 10 mA/cm2, a high mass activity of 8.3 A/(cm2·mg pt) at 50 mV, a large turnover frequency of 8.29 H 2 /s, and outstanding durability with a mere increase of 5 mV over 10000 cycles in acidic electrolyte. Detailed spectroscopic analysis and theoretical calculation results demonstrate that the abundant oxygen on activated bluecoke powders provides an opportunity for the construction of Fe-O y and Pt-O x. The introduction of Fe leads to electron rearrangement in Fe/Pt–O@MKABC, promoting electron transfer and reducing the adsorption free energy of H*, and the interaction between Fe-O y and Pt-O x enhances the hydrogen evolution reaction (HER) performance. [Display omitted] • Utilizing highly porous and oxygen-rich activated bluecoke powders as defect carbon support. • The introduction of Fe optimizes the Pt-O x bonds and significantly reduces the Pt loading. • The loading amount of Pt in the developed Fe/Pt–O@MKABC electrocatalyst is only 0.98 wt%. • The interaction between Fe-O y and Pt-O x accelerates the Volmer-Heyrovsky process. [ABSTRACT FROM AUTHOR]

For large quantities of hydrogen transportation, it is a potential solution for mixing a certain proportion of hydrogen into natural gas pipeline network. In is imperative to seek efficient explosion suppressants of hydrogen enriched compressed natural gas (HCNG). In current work, a 125 L cubic explosion container was developed to conduct the suppression experiments on 20% and 50% HCNG explosion using inhibitory solids of 0.04–0.32 g/L ABC powder and 0.04–0.16 g/L potassium bicarbonate-zeolite (PBZ) composite powder. The thermodynamic and particle size properties of ABC powder and PBZ composite powder were analyzed to interpret these suppression effects. The pressure history curve and explosion flame appearance were recorded. The flame exhibited a deformation and wrinkles characteristic when the solid suppressants were employed. The optimal concentrations of ABC powder and PBZ composite powder suppression were attained. The physical and chemical mechanisms of explosion mitigation with ABC powder or PBZ composite powder were fully revealed. The single inhibitory powder of ABC powder or PBZ composite powder could not fully restrict the HCNG explosion. The current results possessed some practical guidance for restriction of HCNG explosion in industrial confined spaces. • Powder suppressions on 20% and 50% HCNG explosion are conducted. • Flame shows a deformation and wrinkles shape under inhibitory powders. • The inhibitory effect of PBZ composite powder is than that of ABC powder. • Optimal concentrations of ABC powder and PBZ composite powder are attained. [ABSTRACT FROM AUTHOR]

Dry powder inhalers (DPIs) are widely employed to treat respiratory diseases, offering numerous advantages such as high dose capacity and stable formulations. However, they usually face challenges in achieving sufficient pulmonary drug delivery and minimizing excessive oropharyngeal deposition. This review provides a new viewpoint to address these challenges by focusing on the role of swirling flow, a crucial yet under-researched aspect that induces strong turbulence. In the review, we comprehensively discuss both key classic designs (tangential inlet, swirling chamber, grid mesh, and mouthpiece) and innovative designs in inhalers, exploring how the induced swirling flow initiates powder dispersion and promotes delivery efficiency. Valuable design considerations to effectively coordinate inhalers with formulations and patients are also provided. It is highlighted that the delicate manipulation of swirling flow is essential to maximize benefits. By emphasizing the role of swirling flow and its potential application, this review offers promising insights for advancing DPI technology and optimizing therapeutic outcomes in inhaled therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Short-term intake of the egg-protein hydrolysate Newtricious (NWT)-03 improved executive function, but underlying mechanisms and long-term effects, including other cognitive domains, are unknown. Methods: A 36-week randomized controlled trial involving 44 overweight/obese individuals experiencing elevated Subjective Cognitive Failures (SCF; aged 60–75 years) assessed the impact of daily consumption of 5.7 g of NWT-03 or placebo powders on cognitive performance (psychomotor speed, executive function, memory) and Cerebral Blood Flow (CBF), a marker of brain vascular function. Cognitive performance was evaluated using a neurophysiological test battery (CANTAB) and CBF was measured using magnetic resonance imaging perfusion method Arterial Spin Labeling (ASL). Serum samples were collected to determine brain-derived neurotrophic factor (BDNF) concentrations. Results: Anthropometrics, and energy and nutrient intakes remained stable throughout the trial. NWT-03 was well tolerated, and compliance was excellent (median: 99%; range: 87–103%). No overall intervention effects were observed on cognitive performance or CBF, but post-hoc analyses revealed significant improvements on executive function in women, but not men. Specifically, a reduction of 74 ms in reaction latency on the multitasking task (95% CI: −134 to −15; p = 0.02), a reduction of 9 between errors (95%CI: −14 to −3; p < 0.001), and a reduction of 9 total errors (95%CI: −15 to −3; p < 0.001) on the spatial working memory task were found in women. No intervention effects were observed on serum BDNF concentrations (p = 0.31). Conclusion: Long-term consumption of NWT-03 improved multitasking abilities and working memory in women with elevated SCF. Brain vascular function remained unaffected. Sex differences in executive function require additional clarification. [ABSTRACT FROM AUTHOR]

Carbon black, a key ingredient in ancient inks, is used today to make the porous electrodes found in many rechargeable batteries. Understanding how to control its microstructure can pave the way to better-performing batteries. [ABSTRACT FROM AUTHOR]

The development of an inhalation powder (IP) for cancer therapy is desired to improve the therapeutic response and patient compliance. The latest studies highlighted that statins, a class of drugs used in hypercholesterolemia, can have anticancer and antiinflammatory properties. Therefore, the aim of the study was to develop an IP containing liposomes loaded with simvastatin using spray drying technology, as well as to investigate the influence of formulation factors on the quality attributes of the IP by means of experimental design. Results highlighted that the composition of liposomes, namely type of phospholipid and cholesterol concentration, highly influences the quality attributes of IP, and the use of optimal concentrations of excipients, i.e. D-mannitol and L-leucine, is essential to preserve the characteristics of liposomes throughout the spray drying process. The in vitro characterization of the optimal IP formulation revealed that the total percentage of released drug is higher from the IP formulation compared to the powder of active substance (53.38 vs. 42.76%) over a period of six hours, and 39.67% of dry particles have a size less than 5 µm, making them suitable for inhalation. As a conclusion, spray drying technology can be effectively used in the development and preparation of IP containing liposomes. [ABSTRACT FROM AUTHOR]

MoAlB powders with a purity of 96 wt.% were successfully fabricated by a laser‐induced self‐propagating method using molybdenum boride (MoB) and aluminum powders as starting materials under the conditions of an n(MoB): n(Al) ratio of 1.0:1.4 and the laser linear energy density (El) of 0.9 J/mm, and the effect of raw material composition and El on the phase composition and microstructure of the resultant MoAlB powders were investigated. The minimum reflection loss (RLmin) value and effective absorption bandwidth (EAB) of the as‐prepared MoAlB absorber with a thickness of 5.0 mm were only determined as −12.5 dB (at 16.9 GHz) and 0.9 GHz (16.4–17.3 GHz) in the frequency of 1–18 GHz, respectively. Nevertheless, the RLmin and EAB of as‐prepared MoAlB powders oxidized after 3 h at 773 K increased to −18.59 dB (at 15.82 GHz) and 2.13 GHz (15.22–17.35 GHz), respectively, demonstrating that the as‐prepared MoAlB powders are potential candidates for high‐temperature microwave absorption applications. This study proposes a new efficient strategy for the preparation of boron‐based ternary compounds for high‐temperature electromagnetic wave absorption application. [ABSTRACT FROM AUTHOR]

Flash sintering has evolved into touch‐free sintering, where free‐standing workpieces can be sintered without attaching electrodes. Instead, the flash is transmitted from the surface of a reactor into the workpiece with superimposition of a magnetic field. Thus, sintering now depends on two independent parameters: the current used to sustain the flash in the reactor and the current flowing through the induction coil. We present a first report on the influence of these two parameters on the quality of the sintered workpiece. The specimens were made from whiteware, consisting of aggregates of ceramic particles interspersed with particles of a glass phase. The results are presented in a map with the reactor current and the induction current as the control variables. Three regimes are identified: insufficient sintering, good sintering, and the formation of defects. The reactor current emerges as an important variable: densification is poor if it is too low, and defects form if it is too high, with high density achieved in the intermediate regime. High induction currents are needed to achieve good sintering. Touch‐free flash sintering has also been shown to sinter and at the same time transform powders of elemental oxides into a single‐phase multicomponent ceramic. [ABSTRACT FROM AUTHOR]

Radiative cooling pigments offer new opportunities for sustainable carbon neutrality as zero‐energy and zero‐pollution functional materials. However, it is a challenge to prepare inorganic yellow pigments simultaneously with environmentally friendly, high color value, and weather resistance. In this study, a series of alkali metal‐doped γ‐Sm2S3 yellow pigments with near‐infrared reflectance were synthesized. The doping of alkali metal ions reduced synthesis temperature of Sm2S3 from 1300°C to 1000°C. The change in energy band structure induced by alkali metal doping allows the products to exhibit modifiable colors. Typical γ‐[Na]‐Sm2S3 pigment powders have a high near‐infrared reflectance and impressive colors (b* = 78.6, C* = 77.6). Furthermore, colored films made by prepared yellow powders with polyvinylidene fluoride in certain ratios had high near‐infrared reflectance and excellent environmental weathering, resulting in an effective cooling of 4–8°C in outdoor experiments. This work expands the range of options for energy‐efficient building and yellow colorant. [ABSTRACT FROM AUTHOR]

Wind turbine blades are primarily composed of fiberglass composite, posing a significant recycling challenge for the wind energy industry. This paper introduces a novel recycling approach by comprehensively analyzing the pozzolanic reactivity of recycled powder as a new supplementary cementitious material (SCM). A systematic characterization using laboratory techniques is first described, establishing both the chemical and morphological properties of the powder and suggesting that the material was likely to be capable of acting as a pozzolan. The effects of thermal and mechanical processing on the reactivity characteristics of the material were elucidated using a suite of analytical and standardized characterization approaches. It was found that through heat treatment to remove impinging resin and subsequent mechanical processing to synthesize a fine powder, the reactivity of the material could be improved to an extent at which the performance characteristics of a conventional class F fly ash were closely matched. For instance, mortar containing 10% of thermally-mechanically processed powder achieves 95% of the 28-day strength of cement mortar. This paper opens the door for both the use of these materials to bolster dwindling supplies of supplementary cementitious materials, and to provide a much-needed reprocessing route for waste fiberglass which are otherwise highly challenging to dispose of cost-effectively. [ABSTRACT FROM AUTHOR]

A fibre laser was used to weld Q345D/20Mn2 dissimilar steel with and without a Ni60 powder filler. Finite element (FE) simulation of the temperature and stress fields in the laser beam welding (LBW) was conducted COMSOL. Experimental investigation determined the effect of Ni-based powder filled welding on the microstructure, morphology, element content, microhardness and fracture morphology of the weld cross-section. The results show that when the laser power was 2700 W, the scanning speed was 1 mm/s and the out-of-focus amount was 0 mm, the tensile properties of Q345D/20Mn2 steel welds were optimal and deformation was minimal. Under such conditions the depth of the weld pool can reach 2.7 mm and the width 2.8 mm. After the Ni-based powder melts and penetrates the bottom of the base material (BM) along the weld seam, small cytosolic, equiaxed and columnar crystal grains can be observed near the fusion line, and the Ni-based filler powder can achieve a good metallurgical bond with the BM. The location of tensile fracture is at the weld and small tough nests can be observed in the cross-section leading to judgment that the fracture mode is ductile. [ABSTRACT FROM AUTHOR]

In this study, tungsten–copper (W–Cu) composite was fabricated using the sintering process to examine the corrosion, wear and hardness of the fabricated samples at three different temperatures of 1050, 1150 and 1300 °C. The potentiodynamic polarization behavior of the composite samples was evaluated in 3.5% NaCl solution containing different benzotriazole inhibitors. Finally, the microstructure of the W–Cu composite was examined by SEM, TEM, XRD and EDS analyses. The XRD results on the milled samples showed that the optimal conditions were obtained with a ball to powder ratio of 16:1 and a milling time of 15 h, so that the crystals with a size of 16.76 nm were obtained. Also, the highest hardness (185 HV) and relative density (97.34%) were obtained in the samples sintered at 1300 °C. With increasing the wear force, the work hardening increased in the mechanically mixed layer, which led to a rise in the wear rate and a decrease in the friction coefficient. The corrosion behavior of the composite indicated that by addition of 200 ppm inhibitor in the corrosion solution, the corrosion current density decreased from 3.73 to 0.59 μA/cm2 and the corrosion potential improved from − 630.46 to − 336.28 mVSCE. [ABSTRACT FROM AUTHOR]

Novel dual plate-like grains of (Ti, Zr)B 2 and W 2 B 5 toughened solid solution composites were fabricated by the in-situ reaction spark plasma sintering at 1800 °C using (Ti, W)C and ZrB 2 powders. The composites were predominated and composed of the (Zr, Ti, W)C solid solutions and plate-like (Ti, Zr)B 2. In the (Ti, W)C-ZrB 2 reaction system, W promotes the anisotropic growth of (Ti, Zr)B 2 grains, while Ti makes the formation reactions of W x B y thermodynamically feasible. When the addition of ZrB 2 exceeds 40 mol%, W begins to be boronized into W x B y which is mainly composed of plate-like W 2 B 5. The (Ti, W)C-50 mol% ZrB 2 composite with dual plate-like grains of (Ti, Zr)B 2 and W 2 B 5 exhibited the best comprehensive mechanical properties of hardness of 26.5 GPa, flexural strength of 620 MPa, and fracture toughness of 6.6 MPa·m1/2, which provide a new approach for the enhanced toughness without the introducing of metal impurities. • Dual plate-like grains of (Ti, Zr)B 2 and W 2 B 5 toughened (Zr, Ti, W)C ceramics were fabricated by the in-situ reaction SPS. • Ti makes the formation of W x B y thermodynamically feasible, while W promotes the anisotropic growth of (Ti, Zr) B 2 grains. • The 50ZB exhibited a high fracture toughness of 6.6 MPa·m1/2, which provide a new approach for the enhanced toughness. [ABSTRACT FROM AUTHOR]

A hydrothermal method was employed to synthesize the precursor of nano-zirconium carbide, which was subsequently heat treated at high temperatures under vacuum to obtain finely dispersed nanometer-sized zirconium carbide powder through a carbothermic reduction reaction. Scanning Electron Microscopy (SEM) was utilized to examine the microstructure of the precursors obtained under different hydrothermal conditions and carbon contents. The effects of different heat treatment temperatures on the microstructure of the products were analyzed. Transmission Electron Microscopy (TEM) confirmed the boundary coating structure of the hydrothermal precursor and provided insights into the phase structure of the nanometer-sized zirconium carbide. The reaction mechanism and temperature involved in the carbothermic reaction process were determined through calculations. Furthermore, the energy, phase and microstructure of the reaction were investigated using Thermogravimetric Analysis (TG-DSC) and X-ray Diffraction (XRD) at different temperatures. The obtained results revealed that the zirconium carbide precursor was synthesized via the hydrothermal method exhibited a core-shell structure with a boundary coating, which not only ensured uniform contact between C and ZrO 2 particles but also facilitated the formation of zirconium carbide. The results show that the most suitable process parameters are Zr/C 1: 7, 240 °C and 24 h. The thermodynamic calculation results show that ZrO 2 combines with carbon to form CO and ZrC when the temperature reaches 1656.56 °C. As the temperature rises, CO reacts with ZrO 2 to form ZrC and CO 2. TG-DSC shows that the carbothermal reduction reaction starts at 1100 °C and reaches its peak at 1418 °C. XRD analysis confirms that when the temperature reached 1450 °C ZrC appeared. At 1600 °C, the phase transition of ZrC is basically completed. TEM images showed that the synthesized zirconium carbide particles were about 30 nm. [ABSTRACT FROM AUTHOR]

A Mg(OH) 2 –2Al(OH) 3 composite gel, synthesized via the sol-gel method, served as a modifier in the preparation of modified yttria partially stabilized zirconia (Y-PSZ) ceramics. The volume density, apparent porosity, compressive strength, thermal shock resistance, phase composition, and microstructure of the ceramics were systematically characterized. The findings reveal that, upon sintering, the Mg(OH) 2 –2Al(OH) 3 composite gel decomposes into MgO–Al 2 O 3 powder, which in turn in-situ generates a MgAl 2 O 4 spinel reinforcing phase, characterized by its uniform size and distribution. The presence of this MgAl 2 O 4 spinel applies compressive stress to the adjacent zirconia grains, effectively inhibiting their abnormal growth. By occupying the grain boundaries and establishing a mosaic structure, the compressive strength and thermal shock resistance of the Y-PSZ ceramics are significantly enhanced. Notably, an increase in the composite gel quantity correlates with a reduction in both volume density and apparent porosity of the Y-PSZ samples, whereas the compressive strength initially rises before diminishing, and the thermal shock resistance markedly improves. When the amount of Mg(OH) 2 –2Al(OH) 3 composite gel introduced reaches 9 %, the comprehensive performance of the modified Y-PSZ ceramics is optimized. At this point, its compressive strength is increased by 1.26 times compared to the unmodified Y-PSZ ceramics, reaching 732 MPa; moreover, after undergoing 60 thermal shocks, its residual strength retention rate still remains as high as 59.15 %. [ABSTRACT FROM AUTHOR]

The synergistic piezoelectric and osteoconductive properties of barium titanate (BT) and hydroxyapatite (HA) could stir the development of a new generation of synthetic bone graft substitutes, with capability for rapid and safe osseointegration. The research focused on two concurrent approaches for coupling the BT and HA materials: (i) conventional sintering of BT-HA powder mixtures; and (ii) functionalization of pre-sintered BT with HA coatings using magnetron sputtering (MS). Irrespective of the BT/HA ratios ranging from 95/5 to 80/20 wt%, nanocrystalline or highly-crystallized nature of the powders, sub-micron- or micron-sized particle dimensions, and sintering temperature, it was observed that the BT-HA reactivity cannot be prevented above 800 °C. At higher temperatures in the range of 1000–1300 °C, HA undergoes decomposition and extensively reacts with BT, leading to the formation of several secondary phases such as CaTiO 3, Ba 2 Ca(PO 4) 2 , BaCa 6 (PO 4) 4 O, BaCa(PO 3) 4 , and β -Ca 2 P 2 O 7. As a consequence, the cytocompatibility assessed in fibroblast and osteoblast cell cultures, as well as the piezoelectric response, were significantly altered. Applying HA coatings by MS to the sintered BT ceramics successfully preserved their piezoelectric properties, while also providing an unaltered cytocompatible and osteogenic-prone surface. The HA coatings were fully crystallized at post-deposition annealing temperatures of 550 and 700 °C, achieving crystalline qualities comparable to HA powders sintered at 1100 and 1200 °C, respectively. No reactivity events between BT and HA were observed. Partial reactivity was only noticeable upon annealing at 1000 °C. Therefore, it is suggested that the HA coating of BT is effective in seamlessly coupling the piezoelectric and osteogenic properties of the two constituents without compromise. • BT-HA powder mixtures inevitably react at high-temperature to form secondary phases. • The HA osteogenic component can be lost at sintering temperatures above 1000 °C. • The secondary phases lead to a decay of the piezoelectric and biological responses. • HA-magnetron sputtered BT – a feasible solution to overcome inter-phases reactivity. • HA-coated BT yields uncompromised piezoelectric and in-vitro biologic performances. [ABSTRACT FROM AUTHOR]

AlN powders with different O impurity contents were used to fabricate the high thermal conductivity (TC) AlN ceramics of different grain boundary (GB) phase distributions via pressureless sintering. Bending strength, fracture toughness, R -curve characteristic, and fracture mechanism of the ceramics were then investigated. The results showed that the GB phase distributions had great influences on mechanical characteristics of the ceramics. The ceramics with the continuous/semi-continuous GB phases possessed low strength and toughness. Comparatively, the ceramics with the isolated island-like GB phases, especially the fine GB phases at the triple AlN GB junctions, owned higher strength and toughness. The AlN ceramics principally followed the intergranular fracture mode, but the GB phase distribution had great effects on the fractions of transgranular fracture. The AlN ceramics with the continuous/semi-continuous GB phases had a lower fraction of the transgranular fracture, and thus lower crack propagation resistance and reliability than the others. [ABSTRACT FROM AUTHOR]

The inherent brittleness and uniform coloration of Si 3 N 4 materials have traditionally limited their applicability. In this study, colored Si 3 N 4 ceramics were synthesized utilizing α-Si 3 N 4 powder, a ternary mixture of sintering additives, and rare earth oxides (Eu 2 O 3 , Dy 2 O 3). The study focused on assessing the influence of varying Dy 2 O 3 content and holding time on the coloration, mechanical properties, and electromagnetic shielding properties of Si 3 N 4 ceramics. The incorporation of Eu 2 O 3 induced a color shift from gray to yellow-green, while the addition of Dy 2 O 3 facilitated the regulation of brightness in yellow-green Si 3 N 4 ceramics. The results reveal that both hardness and bending strength decreased with prolonged holding time, correlating with changes in sample density. The addition of rare earth oxides can effectively improve the fracture toughness of the Si 3 N 4 ceramics. Specifically, under conditions of 45 min holding time, 2%SED exhibited the highest fracture toughness at 8.45 MPa·m1/2. This enhancement can be primarily attributed to extended retention time, resulting in increased β- Si 3 N 4 phase content, improved fracture energy absorption, and a larger aspect ratio. The introduction of Eu 2 O 3 and Dy 2 O 3 did not significantly alter the electromagnetic shielding properties of Si 3 N 4 ceramics. This study offers novel pathways for the application of Si 3 N 4 ceramics in emerging fields. [ABSTRACT FROM AUTHOR]

The thermal decomposition and sintering kinetics of microfine magnesite were investigated to inaugurate a new One-step process for preparing high-density sintered magnesia. The optimal parameters for the discharging particle size of magnesite through ball milling were determined using an orthogonal experiment and Three-Way Measures ANOVA. The model for the thermal decomposition process of microfine magnesite was established through TGA-DSC and nonlinear regression analysis. Meanwhile, by describing the sintering process of microfine magnesite in detail through microstructure and CTE, the kinetic mechanisms of grain growth at different sintering stages were obtained. The results revealed that increasing the ratio of ball to powder can quickly obtain microfine magnesite which the bulk density reaches 3.45 g·cm−3 after One-step sintering. The thermal decomposition process required an activation energy of only 124.98 kJ·mol−1, which is much lower than existing technology and followed the Two-dimensional phase boundary reaction mechanism R 2. Additionally, the densification process was dominated alternatively by grain boundary diffusion and volume diffusion. This paper provided a detailed theoretical basis and leads a new direction in the One-step preparation of high-density sintered magnesia. [ABSTRACT FROM AUTHOR]

YFeO 3 (YFO) ceramics were synthesized by reverse co-precipitation at different pH values followed by microwave sintering (MS) and spark plasma sintering (SPS) techniques. Also, the effect of the grain size on the magnetic and dielectric properties of the sintered ceramics was examined using various characterization methods. Moreover, FESEM micrographs showed that the particle size of the calcined samples has declined by increasing the pH value. Furthermore, the magnetization curves exhibited weak ferromagnetic behavior in the pre-sintered powder samples. Besides, the M s value was enhanced from 1.26emu/g to 2.3emu/g by an increase in pH from 8.5 to 10.5 owing to reducing the particle size and subsequently raising the amount of uncompensated surface spins. Furthermore, the powder samples showed an increase in the H c and M r values from 15Oe to 28Oe and 0.127emu/g to 0.296emu/g, respectively, with a reduction in particle size from 0.632 μm to 0.272 μm. Additionally, the specimens processed through the sintering techniques demonstrated a remarkable reduction in magnetic characteristics. Therefore, a decrease in magnetic saturation values from 2.3emu/g to 0.43emu/g for the MS sample and to 0.17emu/g for the SPS specimen was attributed to a marked reduction in the amount of free surfaces and subsequently uncompensated surface spins. At last, the observed dielectric characteristics of all the sintered pellets had a common dielectric behavior. This signifies that by increasing the frequency the ε ′ and tanδ decline at lower frequencies and become frequency-independent at higher frequencies based upon the Maxwell-Wagner polarization theory. On the other hand, the ε ′ value for the SPS sample produced at pH = 10.5 underwent a decline of 2.5 times at the low frequency of 200 Hz compared to the MS one due to the significant decrement of the grain boundaries on account of the coarsening of grains. • The reverse co-precipitation method has been chosen to synthesize the YFeO 3 powders. • Through the particle size reduction, the higher pH levels resulted in the increased magnetization. • The spark plasma sintering method resulted in a higher grain growth compared to the microwave route. • The microwave sintering outperformed the spark plasma sintering in magnetic and electrical properties. [ABSTRACT FROM AUTHOR]

Ytterbium oxide (Yb2O3) ceramic powders at different Eu3+ mol concentrations, co-doped with a low molar ratio of Tb3+, were synthesized by the sol–gel process for study before and after the inclusion of the organic ligand thenoyltrifluoroacetone (TTA). The luminescent properties caused by the interactions between the Tb3+–Eu3+ ions before and after the antenna effect caused by the TTA were studied to investigate the relationships among their chemical, physical, structural and optical properties. Before the surface adhesion of TTA, the ceramic powders were composed of cubic crystalline structures that, in turn, consisted of large numbers of agglomerated particles exhibiting xerogel morphologies. The materials presented well-defined dispersive energy spectra, which indicated a suitable chemical composition. Subsequently, changes were induced through the superficial inclusion of TTA, these were characterized by promoting a greater luminescent intensity, especially for the emission bands corresponding to the 5D0→7F0-3 transition levels of the Eu3+ ion. [ABSTRACT FROM AUTHOR]

In this article, we prepared europium ions (Eu3+) doped lithium lutetium double tungstate material using a classical solid-state reaction. X-ray diffraction (XRD), optical absorption and photoluminescence techniques were used to characterize the samples. XRD analysis and structural refinement measurements revealed that LiLu(WO4)2 has a monoclinic structure with a P2/n space group with a formula unit (Z = 2). Additionally, we measured, analysed, and discussed the room-temperature photoluminescence emission and excitation spectra of Eu3+-doped LiLu(WO4)2. The emission spectra show the intra-configurational red emission characteristic of Eu3+ ions, namely 5D0 → 7Fj, J = 0–4. The quenching emission by temperature as well as the 5D0 emission decay curves were measured and discussed. It was found that the quenching of luminescence is obtained for 1.5 at% Eu3+ concentration. Judd–Ofelt intensity parameters (Ω2 = 5.26 × 10−20 cm2 and Ω4 = 1.04 × 10−20 cm2) and the 'Commission Internationale de l'Eclairage' (CIE) chromaticity coordinates were calculated from the emission spectrum of LiLu1−xEux(WO4)2 for x = 0.015. The results indicate that Eu3+-doped LiLu(WO4)2 could be a suitable material for solid-state lighting applications. [ABSTRACT FROM AUTHOR]

Monopotassium orthophosphate (MPOP) crystals in pure form and monopotassium orthophosphate crystals in doped form with non-essential amino acid L-serine (LSMPOP) are obtained by implementing slow evaporation solution growth techniques. The peaks of powder XRD graphical output, while comparing with the powder XRD pattern of pure MPOP, is found that 2θ values shifted slightly for L-serine-doped MPOP and this suggests that the formation of parent material is slightly disturbed by the dopant L-serine. The lattice constant and other crystal characteristics like volume, space group crystal system were analysed in detail by single crystal X-ray diffraction investigations and it is found that it belongs to I-42d space group and tetragonal structure. The infra-red Fourier transforms' spectral studies give information about the functional groups present in the pure and L-serine-doped parent material MPOP. The properties like optical energy gap, lower cut-off wavelength and transmittance were given by ultraviolet visible spectral inspections and the cut-off wavelength is found to be 382 nm for MPOP and 385 nm for LSMPOP, the band gap is found to be 2.85 eV for MPOP and 3.03 eV for LSMPOP. The microhardness of the title materials are calculated by Vickers microhardness studies. The electrical behaviours of MPOP and LSMPOP, such as dielectric constant, ac conductivity, impedance spectroscopy, activation energy are diagnosed and calculated by dielectric analysis. [ABSTRACT FROM AUTHOR]