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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]

Medium- and high-entropy alloys (M/HEAs) mix several principal elements with near-equiatomic composition and represent a model-shift strategy for designing previously unknown materials in metallurgy1-8, catalysis9-14 and other fields15-18. One of the core hypotheses of M/HEAs is lattice distortion5,19,20, which has been investigated by different numerical and experimental techniques21-26. However, determining the three-dimensional (3D) lattice distortion in M/HEAs remains a challenge. Moreover, the presumed random elemental mixing in M/HEAs has been questioned by X-ray and neutron studies27, atomistic simulations28-30, energy dispersive spectroscopy31,32 and electron diffraction33,34, which suggest the existence of local chemical order in M/HEAs. However, direct experimental observation of the 3D local chemical order has been difficult because energy dispersive spectroscopy integrates the composition of atomic columns along the zone axes7,32,34 and diffuse electron reflections may originate from planar defects instead of local chemical order35. Here we determine the 3D atomic positions of M/HEA nanoparticles using atomic electron tomography36 and quantitatively characterize the local lattice distortion, strain tensor, twin boundaries, dislocation cores and chemical short-range order (CSRO). We find that the high-entropy alloys have larger local lattice distortion and more heterogeneous strain than the medium-entropy alloys and that strain is correlated to CSRO. We also observe CSRO-mediated twinning in the medium-entropy alloys, that is, twinning occurs in energetically unfavoured CSRO regions but not in energetically favoured CSRO ones, which represents, to our knowledge, the first experimental observation of correlating local chemical order with structural defects in any material. We expect that this work will not only expand our fundamental understanding of this important class of materials but also provide the foundation for tailoring M/HEA properties through engineering lattice distortion and local chemical order.

Macrocycles are important drug leads with many advantages including the ability to target flat and featureless binding sites as well as to act as molecular chameleons and thereby reach intracellular targets. However, due to their complex structures and inherent flexibility, macrocycles are difficult to study structurally, and there are limited structural data available. Herein, we use the cryo-EM method MicroED to determine the novel atomic structures of several macrocycles that have previously resisted structural determination. We show that structures of similar complexity can now be obtained rapidly from nanograms of material and that different conformations of flexible compounds can be derived from the same experiment. These results will have an impact on contemporary drug discovery as well as natural product exploration.

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]

Due to their large surface area and novel electronic properties, tungsten disulfide (WS2) nanosheets are promising materials for potential photocatalysis applications. The fabrication of large-scale WS2 nanosheets is a fundamentally important step to realize their applications. The liquid phase exfoliation method, which involves the mechanical exfoliation of layered materials in a solvent, has proven to be a feasible technique for fabricating nanosheets with high yields. Here, we systematically examine the optimization of the fabrication of WS2 nanosheets by exfoliating the WS2 powder in isopropyl alcohol, a low boiling point solvent, using a low-power probe sonicator and ball milling method. We show that prolonged sonication produces a concentration as high as 0.64 mg/ml, and the same concentration can be fabricated in less than half the time if the bulk powder is ball milled prior to the sonication. An atomic force microscopy study reveals that the proportions of monolayers and bilayers can be significantly increased if the nanosheet dispersions are centrifuged at a higher speed or sonicated for a long time. The photodegradation measurements reveal that the decomposition rate of methyl orange with nanosheets is at least 10% higher than that with WS2 powder, suggesting that the photocatalytic activity of WS2 can be enhanced if it is reduced to nanosheets. [ABSTRACT FROM AUTHOR]

BACKGROUND: The adhesion of probiotics to the intestine is crucial for their probiotic function. In previous studies, Tremella polysaccharides (TPS) (with sodium casein) have shown the potential to encapsulate probiotics and protect them in a simulated gastrointestinal tract. This study explored the effect of TPS (with sodium casein) on the adhesion of probiotics. RESULTS: Lactobacillus plantarum was coated with TPS and sodium casein in different proportions, and was freeze‐dried. The rheological properties of the mixture of probiotics powder and mucin solution were determined by static and dynamic rheological analysis. Aqueous solutions of probiotic powder and mucin mixture exhibited pseudoplastic fluid rheological properties. The higher the proportion of TPS content, the higher the apparent viscosity and yield stress. The mixed bacterial powder and mucin fluid displayed thixotropy and was in accordance with the Herschel–Bulkley model. The TPS increased the bio‐adhesive force of the probiotic powder and mucin. When using TPS as the only carbon source, the adhesion of L. plantarum to Caco‐2 cells increased by 228% in comparison with glucose in vitro. Twelve adhesive proteins were also detected in the whole‐cell proteome of L. plantarum. Among them, ten adhesive proteins occurred abundantly when grown with TPS as a carbon source. CONCLUSION: Tremella polysaccharides therefore possess probiotic properties and can promote the intestinal adhesion of L. plantarum. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The hard double‐walled structure of Ganoderma lucidum spore powder (GLSP) is difficult for the human body to digest, so it is very important to break the wall of GLSP. In this study, the wall of GLSP was broken by mechanical milling at room temperature (MM‐R) and ultra‐fine grinding at low temperature (UFG‐L), respectively. RESULTS: Compared with MM‐R, UFG‐L could better retain the sporangium powder's morphological and structural integrity. During in vitro digestion, compared with unbroken GLSP, the released amounts of polysaccharides and triterpenes from broken GLSP were significantly increased, and they increased with the increase of specific surface area. The bioaccessibility of polysaccharide and triterpene from unbroken GLSP after the intestinal stage were 29.52% and 5.37%, respectively. The bioaccessibility of polysaccharides and triterpene from broken GLSP by MM‐R after the intestinal phase were 39.73–72.45% and 16.44–24.97%, while those by UFG‐L were 44.53–104.18% and 12.96–32.90%, respectively. CONCLUSION: The active ingredients of broken GLSP showed better digestion and absorption abilities than unbroken GLSP. Moreover, the specific surface area of GLSP by UFG‐L was lower than that by MM‐R, and the bioaccessibility of GLSP by UFG‐L was higher than that by MM‐R. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Ceramic saggars of mullite‐cordierite are currently used to produce cathode powders for lithium‐ion batteries. Strong interactions occur between the LiNi0.8Mn0.1Co0.1O2 (NMC) precursor in the temperature range of calcination (750–1000°C) leading to corrosion and formation of cracks in the saggar. The frequent failure of saggar causes a lot of waste, which could be reduced by choosing corrosion‐resistant materials. To understand the corrosion mechanism in the system MgO–Al2O3–SiO2, the materials MgO, Al2O3, MgAl2O4, and SiC (instead of SiO2) were embedded in premixed NMC precursor and calcined at T = 780°C for 50, 100, 150 and 200 h. The formed phases were determined by phase and microstructure analysis. Finally, the formation of LiAlO2 and Li5AlO4 is associated with a lower growth rate of the corrosion layer compared with Li4SiO4, while MgO is inert. The reactivity with NMC can be ordered as follows: SiO2 > Al2O3 > MgO. [ABSTRACT FROM AUTHOR]

Parahydrogen‐induced polarization (PHIP) is an inexpensive way to produce hyperpolarized molecules with polarization levels of >10 % in the solution‐state, but is strongly limited in generality since it requires chemical reactions/ interactions with H2. Here we report a new method to widen the scope of PHIP hyperpolarization: a source molecule is produced via PHIP with high 13C polarization, and precipitated out of solution together with a target species. Spin diffusion within the solid carries the polarization onto 13C spins of the target, which can then be dissolved for solution‐state applications. We name this method PHIP‐SSD (PHIP with solid‐state spin diffusion) and demonstrate it using PHIP‐polarized [1‐13C]‐fumarate as the source molecule, to polarize different 13C‐labelled target molecules. 13C polarizations of between 0.01 and 3 % were measured on [1‐13C]‐benzoic acid, depending on the molar ratio of fumarate:benzoate in the solid state. We also show that PHIP‐SSD does not require specific co‐crystallization conditions by grinding dry powders of target molecules together with solid fumarate crystals, and obtain 13C signal enhancements of between 100 and 200 on [13C,15N2]‐urea, [1‐13C]‐pyruvate, and [1‐13C]‐benzoic acid. This approach appears to be a promising new strategy for facile hyperpolarization based on PHIP. [ABSTRACT FROM AUTHOR]

The highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) poses a significant threat to the global swine industry. Vaccination is a preventive measure against viral infections. However, the use of vaccines in livestock healthcare programs faces the challenge of safety and delayed immune responses. Earlier studies have shown the potential of modified Bazhen powder as an immunomodulator with significant biological properties, but its effect on vaccines against HP-PRRSV is yet to be studied. This study elucidated how modified Bazhen powder could improve the safety and efficacy of the conventional PRRSV vaccine by evaluating T-cell responses, antibody levels, clinical symptoms, levels of viremia, organ health, and cytokine production. The results revealed that the oral application of modified Bazhen powder in combination with PRRS vaccination improved both cellular and humoral immunity, accelerated viremia clearance, improved lung injury scores, and reduced viral load in the tonsils. The modified Bazhen powder also effectively reduced inflammatory responses following a PRRSV challenge. These findings further highlight the pharmacological properties of modified Bazhen powder as a potential oral immunomodulatory agent that could enhance vaccine efficacy and ensure broad-spectrum protection against HP-PRRSV in pigs. [ABSTRACT FROM AUTHOR]

To understand mechanical behavior of metastable metal-matrix composites, Cu@Ag core–shell powders of two compositions, 51:49 and 80:20 (Cu:Ag in wt%), were compacted by spark plasma sintering. The microstructures of these metastable metal-matrix composites are characterized by single spherical particulates of pure Cu in the matrix of pure Ag in the former case while by aggregates of Cu particulates in Ag matrix in the latter one. The plastic deformation showed enhancement of the ultimate tensile strength compared to both pure component metals by a factor of ca. 3. It is shown that a part of plastic deformation can be correlated by a logarithmic dependence but a possibility to apply a polynomial (quadratic) correlation is suggested. As expected, the shape of the particulate changes during plastic deformation and depends on the level and type of the plastic deformation. A model is proposed showing that this dependence is of a hyperbolic character. [ABSTRACT FROM AUTHOR]

Composites of roasted neem powder and polyaniline (PANI) were synthesized through chemical oxidative polymerization. The major elemental composition of roasted neem bark powder was carbon, oxygen followed by silicon. These prepared composites were subsequently integrated as fillers in an epoxy–polyamine. The formulations show excellent adhesion on mild steel with a rating of 5B. With the addition of roasted neem bark powder and roasted neem bark powder–PANI composite, the pencil hardness increased to 6H from 4H for blank epoxy. Epoxy roasted neem powder (EN)-4% and EN-PANI 2% formulations showed scratch hardness of 1800 kg. All the coatings showed enhanced mechanical properties as compared to blank epoxy coating, as aromatic PANI hinders the chain moment and roasted neem core provides additional strength. The studied variations show excellent acid, alkali, and solvent resistance. Anticorrosive properties were studied using salt spray and electrochemical impedance spectroscopy (EIS). The highest impedance value in terms of logZ is observed for EN-PANI 4% b1 in the range of 8.6, whereas the lowest is for blank epoxy, i.e. ~ 5 logZ. PANI improves the anticorrosive behaviour by forming an oxide layer on the substrate while roasted neem powder acts as a barrier and hinders the flow of moisture and oxygen to reach the substrate. [ABSTRACT FROM AUTHOR]

Nanostructured amorphous composites are novel materials comprising nano-sized crystal phases embedded in an amorphous matrix, but often necessitating ultra-high-pressure molding for preparation. In this study, nanostructured amorphous ZrO 2 –Y 2 O 3 composite ceramics were rapidly prepared for the first time using flash viscous flow sintering without the application of pressure. The relative density of the ZY ceramics increased with increasing current density, and ZY composite ceramics with relative density of 86%–97 % were prepared by FS in a short time of 60 s under 700 V/cm with 0.16–0.56 A/cm2. Furthermore, the sintering activities in FS were compared between partially amorphous powder and crystalline powder. The ceramics prepared by flash sintering of partially amorphous powder show a much higher relative density than that from crystalline powder, suggesting that partially amorphous powder achieves easier densification than crystalline powder in flash sintering under given current density and power dissipation. This phenomenon was attributable to the differing sintering mechanisms between the two materials, i.e., solid-state sintering for crystalline powder and viscous flow sintering for partially amorphous powder. [ABSTRACT FROM AUTHOR]

Extending the transparency range of MgO–Y 2 O 3 composite ceramic to wavelength less than 3 μm is highly desirable, as it broadens their potential applications in infrared (IR) optics. This study illustrates the effectiveness of deagglomerating a mixture of magnesium oxide and yttrium sesquioxide powders, derived from self-propagating high-temperature synthesis (SHS), in achieving this goal. The impact of powder deagglomeration on the microstructure and porosity defects of hot-pressed MgO–Y 2 O 3 ceramic was analyzed using electron and IR microscopy. The results showed that the deagglomeration enhanced the homogeneity of the composite grain mixture, slowed down the grain growth, suppressed the formation of large grains, and significantly reduced the number of porosity microdefects in the material. The optical transmittance increased from 42 % to 77 % at a wavelength of 2 μm (for samples with a thickness of 1.2 mm) when deagglomerated powders were used, compared to non-deagglomerated ones. [ABSTRACT FROM AUTHOR]

Zirconia-toughened alumina (ZTA) ceramics have attracted much attention in the medical field as joint replacement materials due to their good mechanical properties and biocompatibility. However, the flexural strength of conventional ZTA is still slightly insufficient in traditional preparation techniques. In this study, by improving the slurry system, the effects of the solid content of the slurry, additives, and the pH of the slurry on the slurry system were investigated. ZTA powders with a uniform particle size distribution, high degree of sphericity and high flowability were prepared by spray granulation. The mechanical properties, microstructure and biocompatibility of the ZTA pressing were investigated after degreasing and sintering processes. The results showed that the hardness of the prepared ZTA ceramics was 1658.24 ± 28.04 H V, the fracture toughness was 4.016 ± 0.027 MPa m1/2, and the biaxial bending strength was 501.43 ± 21.44 MPa, and the three-point bending strength reached 635 MPa. The ZTA ceramics also possessed good biocompatibility and a low haemolysis rate, which aligns with the requirements of clinical biomedical implant materials. [ABSTRACT FROM AUTHOR]

High-quality Si 3 N 4 powder is a prerequisite for the preparation of high-performance Si 3 N 4 ceramics. In this paper, Si 3 N 4 powders with regular morphology were successfully prepared by pyrolysis of Si(NH) 2 using silicon as a nucleation inducing agent. The mechanism of the silicon in regulating the morphology and particle size of Si 3 N 4 powders was investigated. The results show that when Si(NH) 2 is pyrolyzed directly at 1500 °C under N 2 atmosphere, the products are mainly whiskers accompanied by some particles with irregular shape. In the presence of silicon, the powder particles exhibit a regular hexagonal prismatic morphology. With the increase of silicon content, the whisker content decreases obviously, and the whisker disappears completely when the silicon content exceeds 10 %. Furthermore, the particle size of Si 3 N 4 powder decreases with the increase of silicon content, and the particle size is the smallest when the silicon content is 15 wt%, which is about 802 nm. The nucleation and growth process of Si 3 N 4 powder particles can be divided into three stages. Firstly, silicon reacts with N 2 to form Si 3 N 4 nuclei. Then, amorphous Si 3 N 4 partially decomposes to form Si (g) and SiO (g) and grows on the formed Si 3 N 4 nuclei as the temperature increased. Finally, undecomposed amorphous Si 3 N 4 spontaneously nucleates and grows of the solid-phase diffusion mechanism. Ultimately, all the powders show equiaxial regular morphology. Preferential nitridation of silicon to form Si 3 N 4 nuclei provides nucleation sites for vapor-phase products, which is the key to inhibiting whisker formation and regulating the particle size of Si 3 N 4 powders. [ABSTRACT FROM AUTHOR]

Composite modification of fine SiC powder was implemented by 3-aminopropyl triethoxysilane (KH550) and sodium polystyrene sulfonate (PSS) to improve the dispersion stability of fine powder in water. KH550 was adopted as preliminary modifier and then PSS was used for second modification of KH550-SiC powder. Adsorption studies proved the preliminary modification of KH550 contributed to the adsorption of PSS on SiC particle surface and PSS saturated adsorption capacity was 4.473 mg/g. After KH550 and PSS composite modification, the zeta potential, stability and dispersibility of fine SiC powder were improved. The absolute value of zeta potential of KH550-PSS-SiC particle reached the maximum value of 46.4 mV at pH 12. KH550-PSS-SiC suspension had better stability at the pH range of 2–12. Subsequently, KH550-PSS-SiC powder was mixed with coarse SiC powder to prepare recrystallized SiC (RSiC) green body by slip casting. When the mass ratio of KH550-PSS-SiC powder to coarse SiC powder was 2:3, RSiC slurry with the solid loading of 70 vol% and the viscosity of 636.0 mPa s was obtained and then dense RSiC green body was produced. The density of the prepared RSiC green body was 2.6603 g/cm3 and the relative density was 82.70 %. [Display omitted] [ABSTRACT FROM AUTHOR]

Flake graphite (FG) poses challenges for incorporation into castables due to its hydrophobic nature. In this paper, a strategy combining liquid-phase shear exfoliation (LPSE) with hydrothermal processing was proposed to produce hydrophilic graphene nanosheet/AlOOH nanofiber (GN/ANF) composite powders to address this issue. Under optimal shear exfoliation conditions, the yield of graphene nanosheets (GNs) reached up to 57%. Following a straightforward hydrothermal treatment, the water contact angle of as-prepared GN/ANF composite powders decreased to 53.1°, compared to 103.6° of the original FG. Benefiting from the hydrophilic properties of the composite powders and the homogeneous dispersion of GNs in MgO castables, the sample containing 0.5 wt% GNs exhibited better high-temperature performance than its counterparts. Relative to the control specimen, the slag corrosion index of the sample containing 0.5 wt% GNs decreased from 0.60 to 0.13, while the thermal shock resistance increased by approximately 2.8 times. • Using the liquid-phase shear exfoliation method, the yield of graphene nanosheets reaches 57.02%. • After hydrothermal treatment, the water contact angle of graphene nanosheet/AlOOH nanofiber composite powders decreases from 103.6° to 53.1°. • Adding 0.5 wt% graphene nanosheets to MgO castables reduces the slag corrosion index from 0.60 to 0.13 and increases thermal shock resistance by about 2.8 times. [ABSTRACT FROM AUTHOR]

The pressureless sintering process is essential to densify near net shaped parts with good shape fidelity. In this work, the impact of the particle size distribution and crystallization state on the processing and properties of final sintered multicomponent lithium disilicate (SiO 2 -Li 2 O-K 2 O-P 2 O 5 -Al 2 O 3 -ZnO) was evaluated. Higher densification was achieved by pressureless sintering at lower temperatures for samples prepared with fine glass-based powders (825 °C; ≈96%) rather than coarse crystallized powders (975 °C; 92.9%). However, samples based on fine powders presented a microstructure characterized by low aspect ratio crystals, while those based on coarse powders presented needle-like crystals with high aspect ratio. Best mechanical properties were found in samples prepared with coarse glass powders (relative density≈ 95.1%; Vickers Hardness≈ 5.2 GPa; indentation fracture toughness≈ 2 MPam0.5; flexural strength≈ 317 MPa) sintered at 875 °C-1 h. These results can provide valuable orientations for the post-processing of lithium disilicate glass-ceramics prepared by additive manufacturing techniques. [ABSTRACT FROM AUTHOR]

This study utilized an innovative unalloyed CoCrFeNiTiMo hybrid powder as a joining filler to fabricate high‐strength SiC/HEA/SiC joints via in‐situ reaction. The investigation systematically examines the effects of joining parameters on microstructural evolution and mechanical properties. The filler exhibits high reactivity with SiC, addressing carbon enrichment and low‐strength issues. The resulting joining layer comprises HEA‐rich Si, Mo1.5Cr1.5Si, MoTiC2, and TiC phases. Increasing the temperature facilitates carbon diffusion, transforming TiC into MoTiC2 and forming a MoTiC2‐wrapped TiC structure. At 1400°C for 60 min, the joints attain peak flexural and shear strengths of 312 ± 16 and 137 ± 10 MPa, respectively. Additionally, the joints demonstrate excellent oxidation resistance, with a residual strength of 270 ± 7 MPa after 20 h at 900°C, and favorable high‐temperature mechanical strength, retaining 155 ± 14 MPa at 1000°C. A detailed analysis of the joint formation mechanism is conducted based on experimental results and first‐principles calculations. [ABSTRACT FROM AUTHOR]

Mechanically driven light generation is an intriguing phenomenon holding great promise in various fields. However, the existing mechanoluminescence (ML) materials always suffer from poor self‐recoverability, low repeatability, and environmental disturbance, severely hindering their practical applications. In this work, a self‐activating ML system based on interfacial triboelectrification is created by compositing the Ca6BaP4O17:0.02Ce3+ powders into a flexible polydimethylsiloxane (PDMS) matrix. With no need for pre‐irradiation, the composite film emits self‐activating and self‐charging ML simultaneously in response to the rubbing or stretching stimuli. Accordingly, the Ca6BaP4O17:0.02Ce3+/PDMS exhibits desirable self‐recovery and repeatable ML performance, which could still be recorded (or observed by naked eyes) even after ca. 1000 stretching cycles with a fast self‐recovery period of < 0.1 s. Furthermore, the Ca6BaP4O17:0.02Ce3+/PDMS possesses good thermal stability in a temperature range from 298 to 473 K. The developed Ca6BaP4O17:0.02Ce3+/PDMS is applicable to various fields, and the dual‐mode information storage and photonic skin devices are created as representatives. Compared to the existing oxide‐based ML materials (the ML signal disappears after only several or tens of rapid mechanics cycles), this work breaks through the bottleneck issues on the self‐recoverability, repeatability, and thermal stability, which significantly advances the ML field. [ABSTRACT FROM AUTHOR]

The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is far from over as new strains are emerging all over the world. Selenium as a micronutrient is important for immunity and also has anti-viral activity. Objective: The study evaluated the activity of a Selenium enriched garlic powder (SeGP or SelenoForce®) against SARS-CoV-2 viral replication in vitro and explored its possible mechanism of action. Methods: The anti-SARS-CoV-2 activity assay was carried out in Vero E6 cells in vitro. Human lung carcinoma A549 cells were used to study the antioxidant activity, expression of angiotensin converting enzyme (ACE), transmembrane protease, serine 2 (TMPRSS2) and the activity of proprotein convertase, and furin. Anti-inflammatory activity was evaluated in lipopolysaccharide-activated RAW 264.7 cells. Results: SeGP inhibited the replication of SARS-CoV-2 in Vero E6 cells with an IC50 of 19.59 μg/ml. It exhibited significant antioxidant activity in vitro with IC50 value determined as 43.45 μg/ml. The Selenium enriched product inhibited the expression of ACE and TMPRSS2 and also showed inhibition of furin protease activity. In the presence of SeGP, the secretion of nitric oxide, interleukin −6 and TNF-α were reduced in activated RAW 264.7 macrophages. Conclusion: The results of the study suggest that Selenium enriched garlic powder could inhibit SARS-CoV-2 multiplication in vitro, reduce oxidative stress and inflammatory mediators suggesting that it could be developed as an effective supplement or adjunct therapy to combat viral infections. [ABSTRACT FROM AUTHOR]

Membrane reactors are known for their efficiency and superior operability compared to traditional batch processes, but their limited diversity poses challenges in meeting various reaction requirements. Herein, we leverage the molecular tunability of covalent organic frameworks (COFs) to broaden their applicability in membrane reactors. Our COF membrane demonstrates an exceptional ability to achieve complete conversion in just 0.63 s at room temperature—a benchmark in efficiency for Knoevenagel condensation. This performance significantly surpasses that of the corresponding homogeneous catalyst and COF powder by factors of 176 and 375 in turnover frequency, respectively. The enhanced concentration of reactants and the rapid removal of generated water within the membrane greatly accelerate the reaction, reducing the apparent activation energy. Consequently, this membrane reactor enables reactions that are unattainable using both COF powders and homogeneous catalysts. Considering the versatility, our findings highlight the substantial promise of COF-based membrane reactors in organic transformations. Membrane reactors are efficient alternatives to traditional bath process, yet their limited diversity challenges their applicability to various reaction requirements. Here, the authors report covalent organic framework membrane reactors applied to the Knoevenagel condensation with enhanced performance as compared to homogeneous catalysts. [ABSTRACT FROM AUTHOR]

A novel approach was applied to synthesize B6O using CaB6 and B2O3 powders as reactants. CaB6 and B2O3 were reacted to generate B6O and CaB2O4 at 1573 K, and the by‐product CaB2O4 was removed by acid leaching. It was found that the samples prepared in this work were oxygen deficient (B6Ox, x ≈ .76–.77). The optimal molar ratio of CaB6 to B2O3 was determined to be 3:5, and excess B2O3 could not lead to a change in the value of oxygen occupancy. Scanning electron microscope images showed that regular holes similar to the morphologies of CaB6 particles were exhibited in the final samples, which could be explained by the diffusion of CaB6 during the reaction process. [ABSTRACT FROM AUTHOR]

With the emergence of ultrafast X‐ray sources, interest in following fast processes in small molecules and macromolecules has increased. Most of the current research into ultrafast structural dynamics of macromolecules uses X‐ray free‐electron lasers. In parallel, small‐scale laboratory‐based laser‐driven ultrafast X‐ray sources are emerging. Continuous development of these sources is underway, and as a result many exciting applications are being reported. However, because of their low flux, such sources are not commonly used to study the structural dynamics of macromolecules. This article examines the feasibility of time‐resolved powder diffraction of macromolecular microcrystals using a laboratory‐scale laser‐driven ultrafast X‐ray source. [ABSTRACT FROM AUTHOR]

Upon spray drying of dairy powders, the distribution of components within the droplets can become nonuniform. In this study, the influence of the composition on the drying behaviour, morphological development and surface composition were studied using single droplet drying. The addition of fat was found to result in an earlier locking point (1.1 instead of 1.8 s). The fat content did not influence the morphological development, but the protein and lactose ratios did influence whether the dried particle was smooth or wrinkled. Confocal Raman microscopy revealed that the initial fat, lactose and protein contents influenced the dry surface composition. For example, fat was found on the surface of emulsions that were either rich in fat or in whey protein. [ABSTRACT FROM AUTHOR]

A goal of this study was to investigate the influence of fluidised bed agglomeration process with guar gum (GG) binder (0–0.3%) on the physical and rheological properties of agglomerated milk protein isolate (MPI). Larger and more porous particles were formed by the agglomeration process, resulting in an improvement in powder flowability, wettability and solubility. The agglomerate with 0.1% GG binder exhibited higher viscoelastic properties than other agglomerates, with viscoelastic moduli values decreasing as the binder concentration increased (0.1–0.3%). The findings demonstrate that the agglomeration process with GG improved the powder characteristics of MPI and influenced its rheological properties. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The diffusion of microplastics in the food supply chain is prompting public concern as their impact on human health is still largely unknown. The aim of this study was to qualitatively and quantitatively characterize microplastics in skim-milk powder samples (n = 16) from different European countries (n = 8) through Fourier-transform infrared microspectroscopy in attenuated total reflectance mode analysis. The present study highlights that the use of hot alkaline digestion has enabled the efficacious identification of microplastics in skim-milk powders used for cheesemaking across European countries. The adopted protocol allowed detection of 29 different types of polymeric matrices for a total of 536 plastic particles. The most abundant microplastics were polypropylene, polyethylene, polystyrene, and polyethylene terephthalate. Microplastics were found in skim-milk powders in 3 different shapes (fiber, sphere, and irregular fragments) and 6 different colors (black, blue, brown, fuchsia, green, and gray). Results demonstrate the presence of microplastics in all skim-milk powder samples, suggesting a general contamination. Results of the present study will help to evaluate the impact of microplastics intake on human health. [ABSTRACT FROM AUTHOR]

Due to the poor aqueous solubility of docosahexaenoic acid (DHA), encapsulating it in egg yolk results in a reduction in the hydration properties of egg yolk powder (EYP), subsequently affecting its functional properties. In this study, the effects of vacuum low-temperature spray drying (VLTSD), high-temperature spray drying (HTSD), and freeze-drying (FD) on the hydration properties of DHA-enriched EYP were investigated. Firstly, we optimized the inlet temperature and feed rate for VLTSD (60 °C, 300 mL/h) and HTSD (170 °C, 800 mL/h), while FD was conducted under − 70 °C conditions. The most striking finding of this study was the DHA-enriched EYP prepared by VLTSD exhibited desirable solubility (54.86 g/100 g), water dispersibility (48.63%), and coefficient of stability (24.88%) during rehydration, which was well predicted by low-field NMR. Compared to HTSD and FD, the solubility increased by 16.18% and 45.17%, respectively. Furthermore, at the microscopic level, SEM images and FTIR spectra revealed that VLTSD enhanced the hydration properties by protecting the structural integrity and increasing the hydrogen bonding of the DHA-enriched EYP. The encapsulation efficiency of DHA-enriched EYP prepared by VLTSD, HTSD, and FD were 97.15%, 96.51%, and 81.31%, respectively. According to the quality analysis, VLTSD had the best protection for DHA-enriched EYP in terms of chromaticity, bulk density, storage stability, and sensory evaluation. Therefore, this study confirmed the applicability of VLTSD technology for microencapsulation of bioactive substances such as DHA to enhance the hydration properties of powders. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this experiment was to explore the improvement of tussah pupa powder on the deterioration of pork batter emulsion gel by using proteomics, distribution of moisture, rheological properties and surface hydrophobicity. The results showed that the myosin decomposed as the heating temperature increased; as the increase of the addition proportion of tussah pupa powder at each sterilisation temperature point, compared to the control group, the pH of a pork batter emulsified gel showed a significant increased trend (P < 0.05); the low molecular weight proteins or formed oligomers of tussah pupa powder could be used as fillers to participate in the formation process of gel network; the vitellogenin of tussah pupa powder could form a 'skeleton' in the pork batter system; as the sterilisation temperature at 100 °C (30 min) and 110 °C (30 min), the surface hydrophobicity was the largest as the addition amount 2%. In short, the tussah pupae powder could improve the deterioration characteristics of the pork batter emulsified gel by influencing the pH, surface hydrophobicity and the formation of gel network of pork batter system. This research provided theoretical support for improving the process property of the meat products. [ABSTRACT FROM AUTHOR]

Summary: The study investigates, the potential utilisation of the Garcinia indica linn rind powder as a valuable and healthy ingredient for food industry. Techno‐functional properties revealed the functional attributes which is crucial for product development. Characterisation of the powder and extract revealed the physical, chemical, and structural properties through FTIR, HPLC, and SEM. Therefore, moisture content (5.45%), ash content (2.80%), fibre content (7.56%), and fat content (9.54%) were reported in G. indica linn rind. Phytochemical analysis indicated significant levels of phenolic and flavonoid compounds, suggesting antioxidant potential, supported by inhibition in the DPPH assay with IC50 value of 485.1 μg/mL. In‐vitro assays revealed inhibitory effects on α‐amylase with IC50 value of 58.43 μg/mL and glucose with an IC50 value of 0.39 μg/mL, indicating potential benefits in blood glucose management and weight control. Overall, G. indica rind powder shows promise as a natural ingredient with diverse applications in functional foods and nutraceuticals, offering potential health benefits through innovative product formulations. [ABSTRACT FROM AUTHOR]

The present article investigates the performance of powder-mixed die sink electrical discharge machining (PMEDM) under the influence of micro-flakes graphite (Gr) powder additive in dielectric (1.25 and 2.5 g/l of concentrations) during machining two workpiece materials of D2 steel and mild steel that are extensively employed alloys in the die and mold industry. Micro-flakes are chosen due to the necessity for fewer particles to fill the gap in the machining process, resulting in reduced pollution within the gap. The assessment of the PMEDM procedure's results is conducted based on several parameters, including the material removal rate (MRR), electrode wear ratio (EWR), average surface roughness (Ra), morphology, machined surface elemental content and recast layer. The results indicated that Gr PMEDM process offers higher machining performance in terms of MRR, EWR and the machined surface quality compared to die sink EDM process in pure dielectric. The optimum concentration was found to be 2.5 g/l Gr powder mixed dielectric for both workpiece materials. Furthermore, it was specified that the chemical composition and mechanical properties of the workpiece considerably affect the performance of die sink EDM and PMEDM. Unlike what has been discussed previously in the literature, present study revealed that formation of micro-crack and its density as well as micro-defects on the machined surface is highly dependent on workpiece elemental composition and mechanical properties. The concentration of cracks was particularly higher in areas with higher Cr atomic concentration, which increased the crack density in D2 steel. [ABSTRACT FROM AUTHOR]

In the realm of additive manufacturing, powder bed fusion (PBF) is recognized as an innovative and highly effective technique for manufacturing titanium-based materials. With an understanding of and regulation for the complex microstructural evolution that occurs during the PBF process, several previous studies have been conducted to enhance the reliability, efficiency, and performance of the PBF through investigation and optimization of microstructure evolution in PBF. These studies have examined various aspects, including feedstock materials, process parameters, and post-processing techniques, in order to gain a comprehensive understanding and control over the progression of microstructure in the PBF. Process parameters are widely acknowledged as critical determinants in the PBF process for titanium-based materials, significantly influencing the quality in 3D printed components. Previous studies have provided an in-depth discussion of the effects of process parameters, such as laser power, scanning speed, and hatching space, on the microstructure evolution of Ti-based materials. The primary objective of this review paper is, therefore, to provide a comprehensive and clear explanation of recent efforts, with a particular focus on investigating the complex evolution of microstructures in Ti-based materials during the PBF process. This thorough discussion is devoted to providing a comprehensive understanding of the effects of process parameters on the evolution of microstructures in Ti-based materials. [ABSTRACT FROM AUTHOR]

It is important to utilize the raw colemanite (RC) mineral, which has abundant reserves in the world, and to reduce its particles to smaller sizes for nanotechnology. However, not only the particle size of the produced colemanite powder but also its other properties need to be elucidated. By using the Taguchi design, the RC mineral was ground in a high-energy ball mill. From signal-to-noise (S/N) ratio, the smallest average particle size was found to be 3.10 µm for the experiment E04/nano-sized amorphous colemanite (NAC) powder. The characteristics of as-received RC mineral and synthesized NAC material were investigated using laser particle size analyzer, optical microscopes, SEM–EDS, XRD, TEM, HRTEM, and TGA–DTA devices. It was found that the NAC powder was not homogeneous, a small peak within the 300–20 nm range appeared, and d90, d50, d10, and dmin values were, respectively, 14.6 µm, 3.08 µm, 232 nm, and 26 nm. In the XRD analysis, the pure colemanite, calcite, and silica minerals were determined. The crystal structure of the NAC powder almost turned amorphous, and the crystallite size of (031) peak was reduced to 7.3 nm. It was deduced that the average particle size was 8.29 nm (R2 = 0.86), and the d-spacing value was 0.307 nm. This significant finding was attributed to the mobility of balls and moreover it was interpreted with an equation. An unknown transition in TGA–DTA was referred to the calcite mineral. Finally, it is believed that the synthesized NAC material will be beneficial to engineering studies as a natural/mineral additive. [ABSTRACT FROM AUTHOR]

Blended powder semisolid forming (BPSF) includes powders uniform distribution, mechanical alloying, cold compaction, and semisolid heating. Homogenization of nanoparticles within matrix phase is a crucial step in production of BPSFed parts. In this research, with the aim of providing uniform distribution and dispersion, two sets of experiments were done. Firstly, 316L matrix particles (66–83 μm) and 1 wt% Al 2 O 3 np nanoparticles (50 nm) were mechanically milled at rotational speed of 200 rpm in a planetary ball mill at different mixing times (0.5, 1, 2, and 4 h). Secondly, ultrasonic treatment was added before mechanical alloying to deagglomerate nanoparticles. Subsequently, powders were blended using a planetary ball mill. 316L/1 wt% Al 2 O 3 np blended powders were cold compacted under a pressure of 700 MPa. The semisolid heating process was conducted in a liquid fraction of 30%. Blended powder morphology, microstructure, mechanical properties, and phase formation of the samples were investigated. The obtained results indicate that low mechanical mixing times can only improve distribution. Using ultrasonic before ball milling guaranties uniform distribution and dispersion in BPSF. Ultrasonic treatment significantly deagglomerates clusters of nanoparticles and sticks them to the matrix particle surfaces. BPSFed 316L/1 wt % Al 2 O 3 np composite indicated porosity, hardness, and compressive strength of 7.45%, 267 HV10, and 951 MPa, respectively. Obtained physical and mechanical properties of the sample are superior compared to the properties of parts obtained from casting and powder metallurgy routes. [ABSTRACT FROM AUTHOR]

In the recent past, several studies were reported on meta-structure-based direct metal laser sintering (DMLS) of functionally graded materials (FGM) using virgin/recycled metallic powders. But hitherto little has been reported on DMLS of meta-structure-based FGM using a combination of virgin and mixed metallic powder with a single hopper. This study outlines the use of virgin/single and mixed metallic powder for fabricating FGM using DMLS with a single hopper. The study highlights the DMLS of FGM with 17–4 precipitate hardened (PH) stainless steel (SS) virgin powder in a sandwich layer as 'Weaire–Phelan' meta-structure and mixed powder (comprising of 17–4 PH SS (90% by wt.)-Ni-625 (5% by wt.)–Ti–6Al–4V (5% by wt.) collected as waste/mixed powder from DMLS setup) as the top and bottom layers. Results suggested that the surface roughness (Ra) of 3D-printed (by DMLS) FGM was 12.66 µm, 19.85 µm, and 12.41 µm for the top, middle, and bottom layers, respectively. The Ra was improved to 8.59 µm, 12.35 µm, and 8.67 µm after wear testing. Further, after corrosion (in vitro) testing in simulated body fluid, Ra was observed as 13.36 µm, 14.44 µm, and 13.46 µm, respectively. Overall, the wear and corrosive behavior have shown tuneable 4D characteristics for required surface properties in biomedical applications. The results are supported by scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) analysis. [ABSTRACT FROM AUTHOR]

This paper employed a scaling analysis to represent the processing parameters, affecting the melting process in the dimensionless numbers, identify the relationships of these dimensionless numbers, and develop semi-empirical correlations to predict the width and depth of the melt pool. To develop the correlations, Ti-6Al-4V powder was used to print 38 tracks at various processing conditions. The correlations were then fit into this experimental data using python code to find the constants of the correlations. The correlations were then used to predict the depth and width of the melt pools. It was found that the mean discrepancy between the predicted melt pool dimensions and the experiment is 7%. To evaluate the accuracy of the correlation in predicting the melt pool dimensions of the materials never used during the development of the correlations, the melt pool depth of some tracks made out of stainless steel 316L printed at various conditions was predicted using the model, and it was found that the mean discrepancy between the predicted melt pool depth and experiment is 11%. [ABSTRACT FROM AUTHOR]

This study delved into the incorporation of wild nettle (Urtica dioica L.) leaves powder with virgin olive oil, exploring its potential to enhance nutritional value and health benefits. The antioxidant, antibacterial, and mineral-enrichment attributes of the resultant nettle-infused olive oil were investigated. Phenolic composition analysis revealed that an optimal maceration time of 30–40 minutes leads to maximal phenolic and flavonoid contents (57.66 mg GAE/100 g and 67.18 mg QE/100 g, respectively). The infused oil demonstrated superior radical scavenging activity (DPPH and ABTS assays) compared to virgin olive oil. Notably, nettle infusion significantly elevates zinc (10.12 mg/kg) and iron (13.85 mg/kg) contents. Antibacterial assays exhibited enhanced inhibition diameters and lower MIC and MBC values for nettle-infused oil against various bacterial strains. The study's findings underscore the potential of nettle infusion to enhance the nutritional and functional attributes of olive oil, holding promise for novel culinary and health applications. [ABSTRACT FROM AUTHOR]

This study investigated the effect of the inclination angle of the swirl chamber in a dry powder inhaler (DPI) on the retention of carrier particles. It was found that a small inclination angle can retain most carrier particles within the chamber by promoting constant collisions with the wall. However, care must be taken to avoid a large inclination angle, which can result in a stronger siphoning effect at the top of the swirl chamber. Two DPIs, Cyclohaler® and an in-house DPI, were studied using Euler/Lagrangian simulations to determine the optimal inclination angle for two inhalation pressure drops (2 and 4 kPa) and two carrier sizes (46 and 83 µm). The preferred outcome is for most carriers to remain in the swirl chamber while most drugs leave the inhaler. For an inclination angle of 5° and a carrier size of 46 µm, more than 50% of drugs escaped while less than 3% of carriers escaped. Experimental studies using a next generation impactor (NGI) confirmed the simulation results. This novel finding provides guidance for preventing carrier lactose particles from leaving DPIs. Copyright © 2024 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) is a bioactive and important material for medical applications. Therefore, search for new possibilities in combining hydroxyapatite with other compounds opens a promising path for creating innovative biomaterials. For this purpose, the preparation of effective aqueous colloidal dispersions based on nanohydroxyapatite (nHAp) of varying degrees of crystallinity and morphology was investigated. Nanohydroxyapatite was prepared by co-precipitation with post-processed freeze-drying, hot-air drying, sintering, and hydrothermal synthesis with tri-sodium citrate. The prepared nanosized powders were analyzed by using X-ray powder diffraction, scanning, and transmission electron microscopy techniques. The influence of post-processing techniques, such as lyophilization, freezing, hot-air drying, and sintering, on the crystallinity and morphology of prepared nanohydroxyapatite suspensions was investigated. Aqueous nanohydroxyapatite colloidal dispersions were prepared using deionized water and tri-sodium citrate solution (0.01 % wt.) with an ultrasonic homogenizer. The study demonstrated that the most effective aqueous colloidal dispersion of nHAp (stable for at least 14 days) can only be obtained using a tri-sodium citrate solution together with freeze-drying. When the material shows higher crystallinity and a more clearly rod-like shape, even tri-sodium citrate does not help maintain the stability of the colloids for a long time. These findings are significant for future investigation involving the preparation of new materials based on nHAp, such as hydrogels, membranes, scaffolds, cement, and composites for biomedical applications. They can be applied in theranostics and drug delivery systems. [Display omitted] • An effect of synthesis and post-processing method related to the hydroxyapatite (nHAp) was shown. • The post-treatment of nHAp is critical for its colloidal dispersions. • The use of freeze-drying and tri-sodium citrate allows the colloids to remain stable for at least 14 days. [ABSTRACT FROM AUTHOR]

Potassium sodium niobates (KNNs) have garnered significant attention owing to their lead-free nature and potential for use in self-cleaning membranes. This paper presents the synthesis of (K 0.5 Na 0.5)NbO 3 materials for the fabrication of porous membranes, which enable in situ ultrasonic resonance to effectively eliminate contaminants from the membrane surface. KNN powder was synthesized via solid-state reactions, and the membranes were prepared using conventional sintering techniques. The effects of ball-milling time and calcination temperature on the phase structure, pore size, permeance, flexural strength, chemical stability, and piezoelectric properties were comprehensively investigated. The optimal membranes exhibited an average pore size of approximately 300 nm, a porosity of 23 %, and permeance of 220 L m−2 h−1 bar−1 at a sintering temperature of 1050 °C. A polarized electrical field with a strength of 1 kV/mm was applied to the membranes, resulting in an ultrasonic response of 20 mV at an excitation voltage of 20 V with a frequency of 200 kHz. Furthermore, the in situ anti-fouling performance was evaluated by conducting filtration tests on a 500 ppm oil-in-water (O/W) emulsion, demonstrating that the stationary flux increased by 46.7 % when subjected to an excitation voltage of 60 V. [ABSTRACT FROM AUTHOR]