Matrix Powder Research Articles

Fabrication of (111) oriented BaTiO3 microplatelets by the topochemical microcrystal conversion

Template crystals with high diameter-to-thickness ratio (DTR) were critical to prepare high-performance texture piezoelectric ceramics. The (111) BaTiO3 templates with high DTR larger than 15 were prepared using the molten salt synthesis. Firstly, the optimized molar ratios of BaCO3/TiO2 and NaCl/KCl for the Ba6Ti17O40 (B6T17) precursor were 6.9:17 and 3:1, respectively. The TG-DSC analysis revealed that the optimal calcination temperature was 1060 °C. Secondly, the highest DTR value for B6T17 could reach at 50:1, which further guaranteed final DTR of (111)-oriented BT templates ranged from 15 to 20 by calcined at 950 °C. The excessively high ratios of NaCl/KCl and high calcination temperature were harmful to the high DTR and the template integrity. Finally, activated (111) BT templates induced matrix powders to form textured diamond-shaped grains successfully.

Regulation of Interface Compatibility and Performance in Soft Magnetic Composites with Inorganic Insulation Layers by FePO4 Intermediate Transition Layer.

In the fabrication of soft magnetic composites, the lattice mismatch between the inorganic insulation layer and the iron matrix often leads to the formation of cracks during the molding process, which significantly impairs the operational performance of the materials. Consequently, it is imperative to develop novel strategies for inorganic insulation coatings that offer high electrical resistivity and thermal stability and are less susceptible to cracking during formation. This paper presents a new structure for soft magnetic composites that incorporates FePO4 as an intermediate transition layer between the iron-based soft magnetic particles and the inorganic ceramic insulation layer. This configuration is designed to provide insulation coatings with superior voltage and thermal resistance, as well as high electrical resistivity. The research details the processes forming the FePO4 intermediate transition layer and the SiO2 insulation layer on the iron powder surface, along with their interaction mechanisms. An analysis comparing the scenarios with and without the FePO4 intermediate transition layer shows its beneficial impact on the magnetic properties and mechanical strength of the soft magnetic composites. Further investigations reveal that at a phosphoric acid concentration of 1 wt.%, the FePO4 layer significantly enhances the interface compatibility between the Fe powder matrix and the SiO2 insulation layer. Under these conditions, the Fe@ FePO4/SiO2 soft magnetic composites demonstrate outstanding overall performance: the saturation magnetization stands at 215.60 emu/g, effective permeability at 83.2, resistivity at 57.42 Ω·m, power loss at 375.0 kW/m3 under 30 mT/100 kHz, and radial compressive strength at 15.95 Kgf. These findings offer novel insights and practical approaches for advancing inorganic insulation coating strategies and provide vital scientific support for further enhancing the magnetic and mechanical properties of soft magnetic composites.

Pattern recognition-based aptasensor array for discrimination of matrix effect

Nucleic acid aptamers have attracted considerable attention in recent years, particularly in the fields of disease diagnosis and treatment and biosensing. However, complex matrix effects have severely hindered their progress towards practical application. In this study, the novel strategy of a pattern recognition-based aptasensor array was introduced for target recognition based on the predictable selectivity capability of aptamers by circumventing the challenge of the interference of the matrix effect. As one proof of concept, we chose lactoferrin as the target protein, three selected aptamers with differential affinity as its recognition probes, eleven matrix samples of milk powder as the pattern discrimination model, and AuNPs color as the response signals. In the AuNPs colorimetric arrays, the lactoferrin-added milk powder matrix induced different degrees of protection on the surface of AuNPs particles due to different degrees of binding of lactoferrin to the three aptamer sequences and therefore exhibited differentiated red-to-blue color change along with salt-induced aggregation behaviors. The difference in color responses exhibited with and without lactoferrin addition was considered as the fingerprint pattern of the lactoferrin in each milk powder matrix, followed by the supervised machine learning analysis of linear discriminant analysis (LDA) for better orthogonality to complete the identification and prediction of the unknown samples. By this strategy, eleven kinds of milk powder at the added concentration of lactoferrin (50 nmol/L) presented a distinct response pattern and have been identified and classified with accuracies of 100 % via LDA patterns (three aptamers × eleven milk powder matrices × five replicates) with three canonical factors (91.2 %, 8.58 %, and 0.22 %). Furthermore, the accuracy of 22 unknown samples was 100 %, indicating the achievement in differentiating between different milk powder matrices and the identification of each matrix. The proposed aptasensor array complements the traditional “lock-and-key” single aptasensor and opens a new direction for developing sensitive sensing array systems circumventing complex matrix effects.

Microstructural Evolution and High‐Temperature Tensile Properties of 15Cr‐Reduced Activation Ferritic Steel Processed by Hot Powder Forging of Mechanically Alloyed Powders

Reduced activation ferritic steels are being explored as possible cladding tube materials for nuclear reactors because of their low activation and excellent irradiation resistance. In the current investigation, reduced activation ferritic steel (Fe–15Cr–2W) is processed by mechanical alloying of elemental powders followed by hot powder forging. Mechanical alloying is carried out in a Simoloyer attritor mill (Zoz GmbH), after which the powders are placed in a mild steel can and forged at 1200 °C in H2 atmosphere. X‐ray diffraction and transmission electron microscopy (TEM) investigation reveal that 10 h of mechanical alloying is required to achieve complete dissolution of Cr and W in the Fe matrix powder. The relative density and hardness distribution of the forged slab is evaluated in longitudinal as well as transverse direction to optimize the powder forging operation. Electron backscatter diffraction analysis showed dynamic recrystallization to take place during the course of hot powder forging. Tensile tests are performed at room temperature as well as at elevated temperatures (600 and 700 °C). The yield strength and ultimate tensile strength at room temperature as well as at elevated temperatures are found to be higher than those reported in literature for reduced activation ferritic steels consolidated by other techniques.

Interfacial characteristics and thermal stability of polymer-derived SiCf/Ti composite fabricated by powder hot isostatic pressing

The novel SiCf/Ti composite is prepared by hot isostatic pressing (HIP) with polymer-derived (PD) SiC fiber and powder titanium alloy as raw materials in this work. The interfacial characteristics and thermal stability of the PD SiCf/Ti composite have been systematically investigated. The interfacial properties of the PD SiCf/Ti composites are quantified to discuss the interfacial reaction mechanisms and kinetics. The results show that with the proposed HIP process, the powder matrix can be near-fully dense, and the matrix and SiC fiber are well bonded with a uniform interfacial layer. The major interfacial products are C-Ti compounds and Si-Ti compounds, which are formed by atomic diffusion reaction. During subsequent thermal exposure conditions, the interfacial layer growth is temperature-dependent and diffusion-controlled, following the parabolic relation and Arrhenius law. The frequency factor k0 is 102–103 times lower than that in the chemical vapor deposition (CVD) SiCf/Ti composites, showing better interfacial thermal stability. After thermal exposure, the element diffusion becomes significant, and the microhardness of the near-interface zone is noticeably greater than the matrix microhardness because of the atomic diffusion of C. The microhardness of both the matrix and near-interface zone reaches the highest value after 900 °C/9 h thermal exposure. It is concluded that the PD SiCf/Ti composites with good thermal stability can be successfully fabricated by powder HIP.

Recycling metal-organic framework residues (MOFRs) as bifunctional additives in fabricating porous ceramic membranes

In this work, Fe-MOF residues (Fe-MOFRs) were recycled and reused as a kind of bifunctional additives in the preparation of alumina ceramic membranes. To prevent the unwanted aggregation and grain growth of Fe-MOFR derived Fe2O3 nanoparticles at elevated temperature, Fe-MOFRs were premeditatedly introduced into the alumina powder matrix to construct the composite membrane layer. Results showed that the introduction of MOFRs could reduce the thickness of the membrane layer, attributing to the sacrificial organic linkers and high activity of Fe-MOFR-derived Fe2O3 nanoparticles. However, the thickness of the formed composite membrane layer abnormally increased once MOFRs were overloaded due to the aggregation. Impressively, the surface roughness and Young modulus of the membrane layer were characterized using atomic force microscopy (AFM). The Young modulus of pure alumina membranes showed the same trend as the height, while the trend gradually reversed once Fe-MOFRs were introduced, suggesting that the binding strength between the Fe-MOFR derived Fe2O3 nanoparticles were greatly enhanced. The composite membranes showed improved pure water flux and reduced filtration resistance.

Comparing the remineralization potential of undemineralized dentin powder versus chicken eggshell powder on artificially induced initial enamel carious lesions: an in-vitro investigation

BackgroundWhite 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.Methods100 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).ResultsThe 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.Conclusionbiomimetic UDD and CESP powder should be utilized to treat enamel early carious lesions. However, UDD demonstrated the most significant remineralization potential.

Mechanical, Thermal, and Sound Properties of Bamboo‐Powder‐Filled Polyurethane Composites

AbstractBamboo, which is called “green gold” because of its sustainability characteristics, has many wonderful properties that make it environmentally friendly. In this study, polyurethane (PU) composites used in the automotive industry were produced by adding different amounts of bamboo powders (1, 2.5, 5, 7.5, 10 and 15%, w/v) to PU foams. In this regard, density, light and stereomicroscopic analysis, thermal conductivity, spectroscopic analysis, and mechanical (compression) test have been performed. Further, sound absorption analysis and contact angle analysis have been carried out. Optical and stereomicroscopes showed average pore sizes with range of 258–482 µm. As the bamboo powder increased, the contact angle values decreased from 129 ° to 88 °. Compression force deflection values of the samples declined from 1850 to 360 g/cm2. Similar to the mechanical properties, the thermal conductivities of the PU foams decreased. However, in regards to FT‐IR, no chemical reactions were observed between PU matrix and bamboo powder. The sound absorption test results showed that bamboo powder filled PU foams are sound absorption materials and that rigid PU foam with 2.5% (w/v) (PU‐2.5) bamboo powder sample had better sound absorption properties than the bamboo‐powder‐unfilled rigid PU foam (PU‐0), with an average sound absorption coefficient value of 0.86 at 6300 Hz and 0.71 in the range of 1600–6300 Hz.

3D in situ observation of the capillary infiltration of molten silicon in a SiC/SiC composite by X-ray tomography

The Liquid Silicon Infiltration (LSI) process is used to decrease residual porosity of SiC/SiC composite materials. However, it is not fully mastered since the mechanisms involved at 1500 °C under high vacuum are complex to analyze, especially without direct observation. Previous work had demonstrated the feasibility of using X-ray radiography to observe the front rise of silicon in a SiC/SiC composite material during the LSI process. 2D observations, as a first approach, could give a basic understanding of the mechanisms but raised several interrogations due to the superposition of these phenomena along the thickness preventing any quantification. The setup has been improved in order to make X-ray tomography using a fully integrated DC motor in place of the rotation stage commonly used. The sets of X-ray tomographs confirm two successive fillings. First, the molten silicon rapidly and non uniformly invades the accessible intergranular micro porosity of the powder. Then, the liquid slowly fills the remaining isolated powder areas. Once the SiC matrix is fully saturated, the liquid fills the bigger porosities such as cracks and intra yarn macro porosities. In addition, this 3D analysis enabled to give a better comprehension of the non uniform wetting front in the SiC matrix powder. During the 1st step, the accessibility of the powder was known to have a major effect on the speed of progression. Also, the cracks network plays a key role in the filling of the isolated areas in the powder matrix.

Improvement on Qm in high-power piezoelectric ceramics through [111]c texture engineering

Improving mechanical quality factor Qm is of great significance for high-power applications. Here, a new strategy of the [111]c texture engineering was proposed to enhance the performances of high-power piezoelectric ceramics. The 5 vol% BaTiO3 (BT) templates with the [111]c preferred orientation were introduced into matrix powders of 0.03 Pb(Mn1/3Nb2/3)O3–0.33Pb(Ni1/3Nb2/3)O3–0.28 PbZrO3–0.36PbTiO3 (28PZ(R)) to form the [111]c textured ceramics (28PZ(T)), possessing a texture degree of 74 %. The multiple of uniform density in EBSD increased from 0.63 in randomly oriented 28 PZ(R) to 6.63 in 28PZ(T). The good lattice matching between BT templates and textured grains was observed using high-resolution transmission electron microscopy, confirming the microscopic origin of the [111]c texture. The maximum phase angle θmax of 88.2° was quite near 90° in 28PZ(T), ensuring the optimal Qm value of 1275 and the great figure of merit of 255,000 pC/N. The increased Qm in [111]c texture ceramics was confirmed due to the reduced intrinsic polarization directions rather than the pinning effect of the internal bias field. Larger grain sizes with larger domains restrained the movement of domain walls in 28 PZ(T), which was also favorable to higher Qm. This work may provide a new promising route for further high-power applications.

Reinforcement of hydroxyapatite bone cement via thin glycerol-citrate polyester infiltration: Microstructural, mechanical and in-vitro evaluation

The development of calcium phosphate cements (CPCs) incorporating biopolymers, such as thermoplastic polylactides, is known as an efficient strategy to enhance the physico-chemical, biological, and mechanical properties of CPCs. However, the use of thermosetting polyol citrates as fillers in CPCs has rarely been reported. Hence, the main goal of the present work was to produce composite CPCs based on tetracalcium phosphate–monetite cement matrix (C) and glycerol-citrate polyester (GCA) and to thoroughly study the effect of GCA addition on microstructural, micro, and nano-mechanical as well as in-vitro cellular properties of final cement composites. The GCA polymer was synthesized by esterification of glycerol with citric acid and coated on the C cement powder matrix at a concentration of 2.5 wt% by infiltration in ethanol solution. Two systems were prepared, by drying the composite powder at 105 and 170 °C (denoted as GCA/C105 and GCA/C170), while the respective composite cements were produced by mixing the powders with the 2 wt% of NaH2PO4 liquid phase. The results showed that the GCA polyester had no significant effect on the hydrolysis and transformation of the original cement matrix, and the nanocrystalline hydroxyapatite (Hap) was found as the main hydration product in all types of cement. The cement setting time decreased slightly with the GCA addition. On the other hand, a significant increase in mechanical properties was reached by introducing the GCA polyester into the CPC matrix, achieving more than a 70 % increase in the compressive strength, and about 50 % and 20 % in micro and nanohardness values compared to that obtained for the original C cement sample. The nanoindentation analysis revealed that the improved compressive strength and hardness were due to the stronger boundaries between the platelet-like hydroxyapatite particles in GCA-doped cements and partially caused by the denser, less porous, and more compact microstructures. The results of in-vitro cytotoxicity testing revealed high proliferation activity of the osteoblastic cells in all cement extracts, providing useful information for designing novel composite cements with the potential to be applied as bone substitute materials.

Preparation and Magnetic Properties of Low-Loss Soft Magnetic Composites Using MgO-Phenolic Resin Coating.

Optimizing the interface between a magnetic powder matrix and an oxide-insulating layer is an effective method to improve the permeability and lower eddy current loss of iron-based soft magnetic composites. In this study, in order to improve the bonding strength of the substrate and insulation layer, soft magnetic composites were prepared by pressing and heat treating with reduced iron powder as a magnetic matrix, high-temperature MgO nanoparticles as insulating coating, and phenolic resin as an adhesive. The effects of MgO content on the microstructure and magnetic properties of the composites were investigated. The results of a scanning electron microscopy and an energy-dispersive spectrometer analysis corroborate that the results obtained regarding the frequency characteristics and the resistivity of the iron powder agree with the scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) analysis and confirm their improvement by the presence of an insulating layer of MgO. The resistivity of the sample coated with 4 wt.% MgO is nearly 45 times higher than that of the uncoated sample under the same conditions. The MgO-insulating film formed on the surface of iron powder makes the coated sample have low effective grain size, high resistivity, and low magnetic loss at a high frequency. At 1 kHz, the magnetic loss of the 4 wt.% MgO-coated sample is reduced by 77.3%, and the magnetic loss is only 5.8% compared with the uncoated sample at 50 kHz. This magnetic loss separation study shows that the addition of MgO insulation material can effectively reduce the eddy current loss of the magnetic powder core. The 4 wt.% MgO-coated sample has the lowest hysteresis loss factor and relatively low eddy current loss factor, so it can be determined that the addition of 4 wt.% MgO is the optimum content to attain a low magnetic loss.

Pre-structural patterning approach for enhancing flow characteristics of B-stage film-type epoxy molding compound

Epoxy molding compound (EMC) compositions of silica powder and epoxy matrix have been utilized as encapsulation for semiconductor packaging over the past decades. Among various forms of EMC, film-type EMC offers untapped potential. Utilizing EMC film as an encapsulation material allows larger and more uniform encapsulation behavior especially for panel-level and wafer-level packaging applications. In material aspects, as increases silica contents in EMC film, it can encounter a trade-off relationship between the coefficient of thermal expansion (CTE) and the material's viscosity. As silica content increases, the CTE tends to decrease, which enhances warpage behavior. However, viscosity also tends to increase, which reduces flowability. To overcome these tradeoff relationships, in our study, we have demonstrated a pre-structural patterning approach to enhance flowability of B-stage EMC film without changing the raw compositions of material. By doing that, we can suppose increased flowability of film while having similar thermomechanical properties. For patterning while maintaining B-stage, patterned protection film was fabricated using a brass-based metallic mold and a PDMS/PUA-based soft mold. Subsequently, pre-structural patterned EMC was fabricated by transferring the patterned protection film onto a B-stage EMC film using a laminator. The effectiveness of patterning on EMC film was investigated in both numerical and experimental molding analysis according to rheological, chemical, and thermomechanical characterization. The pre-structural patterning approach demonstrated enhanced flow characteristics via a shortened flow path despite the increased viscosity caused by higher silica content.

Creation of an aluminum matrix composite with a core-shell carbide reinforcing phase with improved strength characteristics using selective laser sintering

Abstract The development of methods for printing metal matrix composites with a ceramic reinforcing phase is an urgent task in materials science. The production of new MMCs with dispersed filling in additive technology facesproblems that are difficult to solve within the hardware framework of the method. Our research group proposed the approach to the production of MMCs using ceramic-metal core-shell particles, with a matrix soluble shell. It makes possible to develop a universal sequence of synthetic steps used to introduce reinforcing ceramic particles into an Al matrix. The introduction of metal-layer coated ceramic particles into the metal matrix allows maximal contact during sintering between the matrix and the reinforcing phase due to improved phases wettability. As a result, a technique was developed for printing a composite using selective laser melting based on an Al powder matrix (50 µm) and reinforcing core-shell carbide particles (TiC/Ni) with varying reinforcement degrees and improved strength characteristics.

Oxygen and air cold plasma for the inactivation of Bacillus cereus in low-water activity soy powder

Cold plasma (CP) technology is a promising alternative to thermal treatments for the microbial decontamination of foods with low-water activity. The aim of this work is study the application of low-pressure CP (0.35 mbar) for the inactivation of Bacillus cereus in a soybean powder matrix using O₂ and synthetic air as ionizing gases. The parameters tested were an input power of 100, 200 and 300 W and an exposure time of 10 to 30 min. The excited reactive species formed were monitored by optical emission spectroscopy, and survival data were analyzed using the Weibull mathematical model. Treatments with both gases were effective in inactivating B. cereus. Air plasma resulted in a maximum 3.71-log reduction in bacterial counts at 300 W and 30 min, while O2 plasma showed the strongest inactivation ability, achieving levels higher than 5 log cycles at 300 W and > 25 min. This is likely due to the strong antimicrobial activity of oxygen-derived radicals together with carbon monoxide as an oxidation by-product. In addition, the Weibull distribution function accurately modeled the inactivation of B. cereus. Cold plasma technology is a promising approach for the decontamination of bacteria in low-water activity foods.

Advantages of Spray Drying over Freeze Drying: A Comparative Analysis of Lonicera caerulea L. Juice Powders-Matrix Diversity and Bioactive Response.

The study investigated the impact of Lonicera caerulea L. juice matrix modification and drying techniques on powder characteristics. The evaluation encompassed phenolics (514.7-4388.7 mg/100 g dry matter), iridoids (up to 337.5 mg/100 g dry matter), antioxidant and antiglycation capacity, as well as anti-ageing properties of powders produced using maltodextrin, inulin, trehalose, and palatinose with a pioneering role as a carrier. Spray drying proved to be competitive with freeze drying for powder quality. Carrier application influenced the fruit powder properties. Trehalose protected the phenolics in the juice extract products, whereas maltodextrin showed protective effect in the juice powders. The concentrations of iridoids were influenced by the matrix type and drying technique. Antiglycation capacity was more affected by the carrier type in juice powders than in extract products. However, with carrier addition, the latter showed approximately 12-fold higher selectivity for acetylcholinesterase than other samples. Understanding the interplay between matrix composition, drying techniques, and powder properties provides insights for the development of plant-based products with tailored attributes, including potential health-linked properties.

Dielectric percolation in ceramic matrix composites

This paper presents the results of an experimental study of the percolation behavior of the complex dielectric constant of ceramic matrix composites (CMC). Samples of piezoactive CMC were obtained by joint sintering of synthesized PZT piezoceramic powder (matrix) and crushed particles of sintered PZT piezoceramics (filler) of different compositions. The experimental dependencies of real and imaginary parts of the complex dielectric constant of CMC on the porosity of piezoceramic matrix and volume content of ceramic filler particles were measured and analyzed. It was shown that the additional porosity of the ceramic matrix resulting from sintering of the CMC masks the dielectric percolation transition, that actually occurs at the volume concentration of ceramic filler close to percolation threshold (V ∼ 1/3).

Effects of locally-gradient Co-doping on the electron properties of Bi2Te2.1Se0.9+0.33wt.% Co composite

Interconnected effects of the locally-gradient Co-doping and electron scattering by filler inclusions has been for the first time observed in thermoelectric Bi2Te2.1Se0.9 + 0.33 wt.% Co composite, prepared via spark plasma sintering (SPS) of matrix and filler powders at temperatures TS=573, 598, 623, 648, 673 and 698 K and at the same time t = 2.5 min. During SPS-process, initial Co inclusions, randomly distributed inside the Bi2Te2.1Se0.9 matrix, act as electron doping sources. High-temperature diffusion embedding of Co atoms in the Bi2Te2.9Se0.1 structure results in increasing electron concentration. This diffusion process corresponds to diffusion from limited doping sources, which are spatially separated inside the Bi2Te2.9Se0.1 matrix. Separate filler inclusion is each such source. Concentration profiles of Co distribution were applied to extract a diffusion coefficient, DCo, of Co atoms inside Bi2Te2.9Se0.1. The DCo increases with TS in accordance with Arrhenius law. Owing to locally-gradient distribution of doping Co atoms, the Co-doping is locally-gradient doping. Initial inclusions, consisting of only Co atoms, are gradually transforming into the “core Co@shell CoTe2” inclusions. This transformation is related to diffusion of Co atoms that is accompanied by subsequent solid-state Co+2Te→CoTe2 reaction. Room-temperature weighted mobility of electrons increases with growing TS. This behavior of mobility can be originated from electron scattering by magnetic moments of the Co cores.

Development of whey protein beverage incorporating encapsulated probiotic strain Lactiplantibacillus rhamnosus NCDC 347 and its physico-chemical characteristics.

In the present study, encapsulated strain Lactiplantibacillus rhamnosus NCDC 347 was used to prepare a novel whey protein-based beverage. The encapsulation process utilized skimmed milk powder matrix and evaluated strain viability, physico-chemical properties, sensory assessment, and shelf-life stability. Encapsulated L.rhamnosus NCDC 347 within skim milk powder maintained viability at 8.0 log CFU/g, forming spherical microcapsules with 1-12 µm concavities. Probiotic addition to whey protein beverages maintained pH and acidity within desired ranges. Physico-chemical analysis showed protein content of 8.71±0.21 % to 10.05±0.42 %, fat content of 0.56±0.24 % to 0.67±0.13 %, viscosity of 5.14 pa/s, and total soluble solids (TSS) of 14.42±0.31 to 16.16±0.23° Brix. The shelf-life study revealed that the beverage remained stable for up to 90days with no significant changes (p>0.05) in sensory analysis. The sensory analysis scored the test sample's acceptability at 7.3±0.41. The protein-rich probiotic drink exhibited favorable sensory qualities. Overall, incorporating encapsulated probiotic strain L.rhamnosus NCDC 347 into whey protein beverages could address daily protein requirements and enhance health.

“Hexacelsian slurry development for 2D woven alumina fiber impregnation in CMC fabrication”

The rheological properties of BAS (BaAl2Si2O8) slurries are investigated in order to optimize the impregnation of an alumina preform to manufacture oxide/oxide composite materials. The fiber preform morphology has been deeply investigated, especially the fiber to fiber gap within tows and compared to the grain size of the matrix powder. The slurry viscosity is measured as a function of powder and organic additives concentration to find the best combination. The optimal combination is evaluated by different measurements including: zeta potential, sedimentation and wettability to verify the slurry behavior for the fibers infiltration. An aqueous slurry containing 20–25 vol% of BAS with 1 wt% of dispersing agent (Darvan 821-A™) improved the rheological properties for fibers infiltration. Finally, characterizations of the composite show a good infiltration in the fiber tows spaces and indicate a mean porosity of 37 vol%, including 9 vol% of macroporosity.