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Exercise physiology and circadian biology are distinct and long-standing fields. Recently they have seen increased integration, largely due to the discovery of the molecular components of the circadian clock and recognition of human exercise performance differences over time-of-day. Circadian clocks, ubiquitous in cells, regulate a daily tissue specific program of gene expression that contribute to temporal patterns of physiological functions over a 24-h cycle. Understanding how circadian clock function in skeletal muscle, as well as other tissues contribute to exercise performance is still in the very early stages. This review provides background on this emerging field with a review of early exercise and time-of-day studies in both human and animals. We then move into the role of the circadian clock and its daily program of gene expression in skeletal muscle with a focus on specific metabolic and physiological outputs that vary over time-of-day. Lastly, we discuss the recognition that the timing of exercise communicates with the skeletal muscle circadian clock to adjust its phase settings and why this maybe important for performance and health. [Display omitted] • The Circadian clock is a molecular mechanism temporally orchestrating mammalian physiological functions on a 24-h cycle. • Exercise performance exhibits diurnal patterns, which peaks in the late afternoon/evening (16:00–19:00 h). • The timing of exercise serves as a zeitgeber, shifting clock phase to promote alterations in metabolism and clock output. • Exercise-induced phase shifts in the muscle clock occur independently and do not affect SCN circadian rhythms. [ABSTRACT FROM AUTHOR]

High-purity SiC ceramic membrane has gained tremendous attention in the treatment of various corrosive wastewaters. Additive manufacturing technique makes it possible to fabricate high-purity SiC ceramic membrane with complex configurations. Here, we proposed a route for the preparation of high-purity SiC ceramic membrane support using digital light processing and SiC whisker reinforcement. With the increase of whisker content, the viscosity of SiC w /SiC photosensitive slurry increased due to the formation of whiskers agglomerations; the average pore size shifted from 3.15 μm to 1.35 μm with the occupation of large pores by SiC whiskers. In addition, the compressive strength of the ceramic support increased from 10.7 MPa to 16.7 MPa because of the decline in pore size and the toughening effects by SiC whiskers. So, the introduced SiC whiskers enhanced the pore connectivity and mechanical strength of the porous ceramics. This work provides a feasible path to manufacture high-purity SiC ceramic membrane support with complex configuration, high pore-connectivity and excellent mechanical properties. [ABSTRACT FROM AUTHOR]

This investigation was aimed at finding the optimum replacement level of waste brick powder (WBP) as a partial replacement of cement. For this purpose, three groups of tests are made: fresh, mechanical, and permeation properties. Eight mixes with different percentages of replacing ratios are as follows: 10, 15, 20, 25, 30, 35, 40, and 50%. In addition to the reference mix without powder replacements, the experimental programs include three groups of tests: fresh properties (flow test and fresh density), mechanical properties (dry density, compressive strength, and flexural strength), and transport properties (water absorption ratio, rate of water absorption, i.e., sorptivity, and permeable void ratio). Also, an ultrasonic velocity impulse test was made. The flowability and density of fresh mixes are decreased linearly as the amount of WBP increases for the constant water/binder ratio. However, the density of the in-hardened state was found to be slightly higher than the reference mix for mixes with a brick powder content of up to 20%. Results indicate that strengths for mixes containing WBP are higher than those for the control mix. The highest strength was examined in the mix with 15% WBP for both compressive and tensile strengths of specimens. Generally, the brick powder reduced the ability of mortar to transfer liquid, as was clear from the results of the permeability test results. Empirical relations were proposed according to experimental results. [ABSTRACT FROM AUTHOR]

• Relationships between skeletal muscle echogenicity and physical function were small to moderate but highly consistent. • Sub-analyses determined minimal between-muscle differences in predictive ability. • Ultrasonic echogenicity should be considered part of early detection screens for sarcopenia and other diseases. • Combining muscles tended to strengthen the model, although muscle quality appears systemic, allowing for a single scan to represent the total body. Assessment and quantification of skeletal muscle within the aging population is vital for diagnosis, treatment, and injury/disease prevention. The clinical availability of assessing muscle quality through diagnostic ultrasound presents an opportunity to be utilized as a screening tool for function-limiting diseases. However, relationships between muscle echogenicity and clinical functional assessments require authoritative analysis. Thus, we aimed to (a) synthesize the literature to assess the relationships between skeletal muscle echogenicity and physical function in older adults (≥60 years), (b) perform pooled analyses of relationships between skeletal muscle echogenicity and physical function, and (c) perform sub-analyses to determine between-muscle relationships. CINAHL, Embase, MEDLINE, PubMed, and Web of Science databases were systematically searched to identify articles relating skeletal muscle echogenicity to physical function in older adults. Risk-of-bias assessments were conducted along with funnel plot examination. Meta-analyses with and without sub-analyses for individual muscles were performed utilizing Fisher's Z transformation for the most common measures of physical function. Fisher's Z was back-transformed to Pearson's r for interpretation. Fifty-one articles (n = 5095, female = ∼2759, male = ∼2301, 72.5 ± 5.8 years, mean ± SD (1 study did not provide sex descriptors)) were extracted for review, with previously unpublished data obtained from the authors of 13 studies. The rectus femoris (n = 34) and isometric knee extension strength (n = 22) were the most accessed muscle and physical qualities, respectively. The relationship between quadriceps echogenicity and knee extensor strength was moderate (n = 2924, r = –0.36 (95% confidence interval: –0.38 to –0.32), p < 0.001), with all other meta-analyses (grip strength, walking speed, sit-to-stand, timed up-and-go) resulting in slightly weaker correlations (r : –0.34 to –0.23, all p < 0.001). Sub-analyses determined minimal differences in predictive ability between muscle groups, although combining muscles (e.g., rectus femoris + vastus lateralis) often resulted in stronger correlations with maximal strength. While correlations are modest, the affordable, portable, and noninvasive ultrasonic assessment of muscle quality is a consistent predictor of physical function in older adults. Minimal between-muscle differences suggest that echogenicity estimates of muscle quality are systemic. Therefore, practitioners may be able to scan a single muscle to estimate full-body skeletal muscle quality/composition, while researchers should consider combining multiple muscles to strengthen the model. [Display omitted] [ABSTRACT FROM AUTHOR]

The rapid development of additive manufacturing techniques enables the preparation of SiC ceramics with complex configurations; however, the high sintering temperature and defects-control are still great challenges during processing. Thus, SiC ceramics were prepared by digital light processing followed by liquid phase sintering using Al 2 O 3 –Y 2 O 3 additives in this study. The photopolymerization of the SiC slurry, microstructures and mechanical properties of the sintered ceramics were investigated. The Al 2 O 3 –Y 2 O 3 additives enhanced the curing ability of the photosensitive SiC slurries by reducing the absorbance and scattering of UV light. The liquid phase accelerated the densification of the ceramics by particles rearrangement and interfacial bonding. Thus, the flexural strength of the ceramics increased from 41.0 MPa to 62.8 MPa with sintering temperature increasing. [ABSTRACT FROM AUTHOR]

Non-uniform shrinkage of SiC precursors will lead to cracking and thus weaken the mechanical properties of the C f /SiC composites. This study used the pressure-assisted gel impregnation method to introduce SiC particles (SiC p) into the carbon fiber preform and combined the PIP technique to fabricate C f /SiC composites. The mechanism of enhancing the mechanical properties of composites was studied. Results showed that SiC p effectively eliminated matrix cracking, and the PyC interface layer inhibited interfacial crack propagation. The combined effect of the two resulted in a significant improvement in the mechanical properties of the composites. Specifically, the maximum flexural strength of the C f /SiC composites was 360.63±26.02 MPa, and the maximum fracture toughness was 8.57±1.82 MPa·m1/2. [ABSTRACT FROM AUTHOR]

This work presents a Finite Element approach to model the in-plane mechanical behavior of C/C-SiC fabrics at the lamina level, including the non-linear response of diverse lay-ups and the bending-to-tensile strength ratio at failure. The material model employs a decomposition into two idealized phases, which can be exploited to capture matrix- and fiber-dominated responses at a high level of abstraction. The constitutive law of the matrix phase adopts a Continuum Damage approach driven by two Tsai-Wu surfaces, while a quasi-brittle behavior is attributed to the fibers phase. This decomposition effectively represents the influence of matrix degradation on the response and failure of the laminates. Moreover, simulations reveal that a statistical distribution of the strength is required to represent some of the experimental outcomes. The correlation with experimental data that was achieved points out that the technique is a promising tool for supporting the early design phase of CMC structures. [ABSTRACT FROM AUTHOR]

This study focuses on the relationship between porosity, surface roughness, microstructure, strength, and thermal properties, as well as their effect on the bioactivity and biodegradability of fabricated akermanite (AK; Ca 2 MgSi 2 O 7) bioceramic scaffolds. Firstly, we prepared the AK nanopowders using the mechanical activation method, mixed them with varying proportions of space-holder agent (NaCl), specifically 15, 20, 30, 40, and 50 vol%, and sintered them at 1200 °C to create porous scaffolds. We investigated the physical properties and microstructure using the Archimedes method and field emission scanning electron microscopy (FE-SEM), respectively. The mechanical properties in terms of microhardness, compressive strength, longitudinal modulus, Young's modulus, bulk modulus, and shear modulus were measured. The bioactivity and biodegradability of prepared scaffolds were assessed after soaking in simulated body fluid (SBF) for 10 days by FE-SEM and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), respectively. The results revealed that porous scaffolds with suitable mechanical properties, bioactivity, and biodegradability were prepared. The porosity had a significant impact on the mechanical and biodegradability of the investigated scaffolds. It reduced mechanical properties slightly while improving bioactivity and biodegradability. The microstructure study displayed that all scaffolds formed apatite layer on their surfaces. This is because of good bioactivity and the suitable porosity level of AK. The obtained findings provide promising prospects for the future use of AK in bone tissue engineering. [ABSTRACT FROM AUTHOR]

To determine normal hip adduction- and abduction strength and range of motion (ROM) values for youth and adult female national team football players, and evaluate if increasing age, playing position and leg dominance were associated with these strength and ROM values. Cohort study. National football center. 344 unique asymptomatic female football players. Hip internal/external rotation (°), Bent Knee Fall Out test (cm), hip adduction/abduction strength(N) and ratio, and normalised hip adduction/abduction torque (Nm/kg). A total of 504 assessments were performed. A total of 107 players underwent two (n = 67), three (n = 27) or four (n = 13) assessments. Mean peak hip adduction strength was 39% greater in 20 + Y old players 170 (±53 N) than in 13Y old players 122 (±28 N). Normalised hip adduction torque was 9% greater: 2.5 (±0.8Nm/kg) versus 2.3 (±0.5Nm/kg). A positive association between age and all strength measurements was found, while a negative association between age and hip external rotation and total hip rotation was found. No clinically relevant differences were found for the associations between playing position, leg dominance and hip strength- and ROM values. Normal values for hip strength and range of motion in youth and adult female national football players are presented that can be used as clinical reference values. • Normal values for hip strength and ROM in female football players are presented. • Adult players demonstrated less hip external and total rotation than youth players. • Adult players showed higher strength values than youth players. • Strength asymmetry scores up to 12–14% are common in female football players. [ABSTRACT FROM AUTHOR]

Two formulations of high-temperature organic composite coatings containing Al flakes, nano-TiO 2 were designed and low-melting glass (LMG) powder was added to the second for comparison. The properties of two coatings before and after the heat exposure tests were investigated. At room temperature, the large particles of LMG powder shortened the diffusion path of corrosive medium and had low interface binding strength with Al flakes, which has a negative effect on the barrier properties and strength of the as-prepared coating. After exposed to 600 °C for 300 h, the binder—silicone-modified acrylic resin—decomposed into silica, releasing gaseous products and generating a large amount of cavities inside the coating. Barrier properties and strength of the coating without added LMG powder severely deteriorated. At high temperatures, LMG in the viscous flow state infiltrated into the surrounding cavities by capillary action, forming a glass network and leaving in-situ holes. These holes deteriorated the barrier properties of the coating. The glass network filled in the cavities increased the coating strength and had a barrier effect on the diffusion of corrosive medium. [ABSTRACT FROM AUTHOR]

The mechanical properties and structural evolution of sodium borosilicate glasses under the uniaxial tensile process were investigated through molecular dynamics simulation. The simulated properties of sodium borosilicate glasses were in good agreement with the experimental values. [BO 3 ] and Na+ compensated [BO 4 ] groups were generated in the glass network in low boron content, while [BO 3 ] appeared with increasing boron oxide. The structure descriptor, F net synthesized the structure and energy information of the glass network which was positively correlated with Young's modulus. The strength has been diminished due to the decreased degree of polymerization of the glass network and the migration of Na+ cations. Simultaneously, the elastic deformation of sodium borosilicate glass arose from the motion of Na+ cations and alterations in the Si-O-Si bond angle. Moreover, the plastic deformation of sodium borosilicate glasses was attributed to the transition from [BO 4 ] to [BO 3 ] and the higher mobility of [BO 3 ] than [BO 4 ] and [SiO 4 ]. [ABSTRACT FROM AUTHOR]

To improve the strength of Al 2 O 3 specimens produced using the water-stabilized plasma spraying technique (WSPSAO), this study investigates the effect of structural modification on the mechanical properties of WSPSAO using the Al-Cu-O reaction between the metal, atmospheric oxygen, and base material. A Cu-powder layer is applied to the specimen surface, melted, and oxidized at high temperatures. It penetrates into the specimen, resulting in significant microstructural modification deep in the specimen. After modification, uniaxial Al 2 O 3 , CuO, Cu 2 O, and CuAl 2 O 4 are formed in the specimen, resulting in a denser and more uniform structure than that of the original material. The bending strength of the coated surface is 145 MPa, and that on the opposite side of the coated surface is 118 MPa, which is 130%–180% higher than the original strength of the base material. [ABSTRACT FROM AUTHOR]

The microscopic mechanical properties including the bending strength and Young's modulus for Si 3 N 4 ceramics doped with Y 2 O 3 and Al 2 O 3 which was immersed in 5 wt% sulfuric acid solution using microcantilever beam specimens was investigated in comparison with the macroscopic results obtained in conventional three-point bending tests. Both the properties sharply dropped in very short periods of the corrosion in the microcantilever tests, resulting from the dissolutions of yttrium and aluminum ions of grain boundary glass networks, followed by the hydration. After the drops at the beginning of the corrosion, they showed little degradation afterwards. The degradation behaviors of the mechanical properties are basically the same as those in conventional macroscopic approaches; however, they changes appear in very short periods of the corrosion in the microcantilever bending tests. This study also verified that a small difference of a ratio of sintering additives results in different grain boundary strengths of Si 3 N 4 ceramics. [ABSTRACT FROM AUTHOR]

A Cu-coated Al 2 O 3 substrates which can be used for power modules are prepared via sintering and reduction of CuO–SiO 2 film onto the surface of Al 2 O 3 ceramic without precious metal brazing filler or high-vacuum equipment. This method has a significant cost advantage over the existing technology. Effects of oxygen partial pressure from sintering atmosphere and SiO 2 content on microstructure and mechanical properties of Cu/Al 2 O 3 interface are systematically investigated. Phase compositions and morphologies of sintered Cu 2 O layer, reduced Cu layer and reactive layer are characterized via X-ray diffraction and scanning electron microscopy. In addition, physicochemical changes within CuO–SiO 2 during sintering are characterized by thermogravimetry-differential scanning calorimeter. It is found that oxygen and SiO 2 can promote the generation of Cu 2 O–CuO–SiO 2 eutectic phase with low melting point upon sintering, which increases the thickness of reaction layer and the densification of Cu layer. The shear strength between the Cu layer and the Al 2 O 3 substrate is enhanced with the increase in Cu layer densification degree, while varying in irregular manner with the thickness of reaction layer. In particular, the highest shear strength of 62.70 MPa is obtained at oxygen partial pressure of 0.02 atm and SiO 2 content of 1.5 wt%. [ABSTRACT FROM AUTHOR]

Development of restorative materials capable of mimicking optical and mechanical performance of natural teeth is a quest in aesthetic density. Yttria-Stabilized Zirconia (YSZ) ceramics represent one of the most popular choices for dental restorations, owing to their biocompatibility, white colour, and the possibility to use CAD-CAM technologies. In particular, YSZ doped with 3 mol. % yttria (3YSZ) is popular because it presents high strength. Nonetheless, the limited light transmission of commercially available high strength 3YSZ does not meet the requirements of highly aesthetic cases. On the other side, YSZ presenting a larger portion of yttria are more translucent but exhibit modest strength. Here, we report on fabrication of dense zirconia nanostructures in bulk form via conventional pressure-less sintering at temperatures down to 1100–1200 °C, achieving highly translucent and strong 3YSZ with significant opalescent behaviour. Both Hall−Petch and inverse Hall-Petch relationship were observed in 3YSZ samples with average grain size in the range of 250 nm and 55 nm, demonstrating the importance of grain size control to enhance both optical and mechanical properties of zirconia ceramics, simultaneously. Maximum biaxial strength of 1980 ± 260 MPa, in-line light transmission of 38% in the visible spectrum and opalescence approaching that of enamel were obtained at optimum grain size of 80 ± 5 nm. The notable optical properties are linked to the miniaturization of the residual pores and refinement of grain size towards the nanoscale while the superior mechanical strength is justified by the activation of different energy dissipation processes at nano and macroscale. [Display omitted] [ABSTRACT FROM AUTHOR]

To compare the timeline for post-operative quadriceps and hamstrings strength recovery following anterior cruciate ligament reconstruction (ACLR) using either a quadriceps tendon (QT) or hamstring tendon (HT) autograft. Patients (≤18 years) who underwent ACLR using autograft QT or HT were included. Isokinetic strength was extracted at 3, 6, and 12 months post-operatively. Effects of time and graft type on quadriceps or hamstring limb symmetry index (qLSI/hLSI) was assessed with two-way repeated measures ANOVA. Between group differences at each time point were assessed with unpaired t-tests. Chi-square and Kaplan-Meir analysis analyzed the proportions of subjects able to achieve ≥90% LSI. A total of 75 subjects (QT n = 38 HT n = 37,15.8 years) were included. There were significant differences in qLSI, with greater symmetry within the HT group at all time points. A higher proportion of subjects with HT grafts were able to achieve ≥90% qLSI within 12 months of surgery (81% vs 45%, p = 0.001). Compared to those with HT autografts, adolescents with QT autografts demonstrate a prolonged timeline for quadriceps recovery. While mean strength values above 90% are achieved, a significantly lower percentage of QT patients are able to achieve 90% qLSI by 12 months post-op. • Patients who have quadriceps tendon autografts take longer to recover quad strength. • Fewer patients with quadriceps tendon autografts achieve 90% limb symmetry index. • Patients with hamstring tendon autografts are slower to recover hamstring strength. [ABSTRACT FROM AUTHOR]

The purpose of this study was to analyze the effect of two different programming models of resistance training (RT) on metabolic risk, anthropometric variables, and relative strength in elderly women. The research was a prospective and comparative longitudinal study with a non-probabilistic random sample. Twenty-two elderly women (64 ± 3 years) was divided into two experimental groups being the Linear programming (LP, n = 12) and Daily undulatory programming (DUP, n = 10), with 3 sessions/week for 12 weeks. Submaximal strength (10RM) was evaluated in the horizontal leg press (HL), pulldown (PD), leg curl (LC), vertical bench press (BP), and leg extension (LE). Anthropometric variables, food intake (R24h) and submaximal strength (10RM) was analyzed. Participants were initially classified as overweight or obese evaluated by body mass index (BMI) and percentual of fat mass (%FM) and with moderate to high risk to develop metabolic diseases evaluated by hip-waist ratio (HWR), waist-height ratio (WHR) and waist circumference (WC). There is no change for metabolic risk and anthropometric variables after the intervention period. There was a significant improvement for relative strength accessed by 10RM and body weight (10RM/BW), and lean body mass (10RM/LBM) (p < 0.05), with large or medium effect size for most of variables after 12 weeks of RT. As a conclusion, both programmings increased relative strength after 12 weeks of RT with attenuated change in body composition and metabolic risk in elderly women in both programming groups and all those strategies can be used in elderly women to improve strength. [ABSTRACT FROM AUTHOR]

The intricate structure of ceramic cores is crucial in producing high-temperature-resistant hollow blades. Traditional techniques for ceramic cores preparation, such as hot injection, rely heavily on moulds, thus limiting the production of complex structures in ceramic cores. Stereolithography 3D printing technology provides a novel approach to creating these cores, leveraging its precision and model customization capabilities. However, issues like the challenge of effectively controlling both porosity and strength hinder its widespread adoption. In this study, high-performance ceramic cores reinforced with in-situ YAG were successfully prepared by adding Y 2 O 3 using stereolithography 3D printing technology. Thorough thermodynamic calculations for Y 2 O 3 incorporation into Al 2 O 3 -based ceramic cores were systematically analysed, revealing the formation of Y 3 Al 5 O 12 (YAG) at elevated temperatures due to Y 2 O 3 and Al 2 O 3 interaction. Subsequently, the variations in microstructure and properties were investigated across different temperatures. Due to diffusion, YAG sintered necks and cohesive framework were formed on the surface of Y 2 O 3 , resulting from the reaction between Y 2 O 3 and Al 2 O 3. YAG sintered necks and Y 2 O 3 effectively inhibited crack deflection. The high degree of densification of the in-situ generated YAG and cohesive framework improved the mechanical properties; meanwhile, the presence of porosity between YAG and Al 2 O 3 contributed to the enhancement of porosity. The cores exhibited exceptional mechanical properties at 1823.15 K. The open porosity was 30.08%. The flexural strengths were 41.2 MPa (298.15 K) and 32.0 MPa (1773.15 K). The design of YAG sintered necks by adjusting the sintering temperature introduced a new idea for synergistically adjusting porosity and strength. The advancement is anticipated to improve the production of intricately structured ceramic cores with superior performance. [Display omitted] [ABSTRACT FROM AUTHOR]

SiC reticulated porous ceramics (SRPC) was the critical part of porous media burners. During the ignition and shutdown process of porous burner, SRPC have to subject the large thermal stress caused by sharp temperature gradients. Meanwhile, most of the heat exchange in the burner is achieved through the high-temperature radiation heat transfer of the medium material. The strength and infrared emissivity of SRPC directly determined their service life and heating efficiency. In this work, a multi-layer strut in SRPC was constructed to improve the strength and infrared radiation properties via vacuum infiltration and spraying, including SiC skeleton, dense alumina transition layer and Ca/Cr co-doped LaAlO 3 coating. The results indicated that the multi-layer strut significantly increased the strength of SRPC, and the Ca/Cr co-doped LaAlO 3 coating increased the boiling rate of porous burner from 25.5 °C/min to 31.2 °C/min. Furthermore, the Ca/Cr co-doped LaAlO 3 coating with its high infrared emissivity (0.80) increased the surface temperature of porous burner, also reduce the pollutant emission (CO and NO x) of SRPC. In addition, Ca/Cr co-doped LaAlO 3 promoted the combustion of low concentration methane, the lean-burn limit of methane stable combustion for porous burner had been enlarged, even the mixed gas containing 4 vol% methane could achieve stable combustion. [ABSTRACT FROM AUTHOR]

Non-steroidal anti-inflammatory drugs (NSAIDs) are frequently consumed by athletes to manage muscle soreness, expedite recovery, or improve performance. Despite the prevalence of NSAID use, their effects on muscle soreness and performance, particularly when administered prophylactically, remain unclear. This randomized, double-blind, counter-balanced, crossover study examined the effect of consuming a single dose of each of three NSAIDs (celecoxib, 200 mg; ibuprofen, 800 mg; flurbiprofen, 100 mg) or placebo 2 h before on muscle soreness and performance following an acute plyometric training session. Twelve healthy adults, aged 18–42 years, completed a standardized plyometric exercise session consisting of 10 sets of 10 repetitions at 40 % 1-repetition maximum (1RM) on a leg press device. During exercise, total work, rating of perceived exertion, and heart rate were measured. Maximum voluntary contraction force (MVC), vertical jump height, and muscle soreness were measured before exercise and 4-h and 24-h post-exercise. We found no significant differences in total work, heart rate, or rating of perceived exertion between treatments. Additionally, no significant differences in muscle soreness or vertical jump were observed between treatments. Ibuprofen and flurbiprofen did not prevent decrements in MVC, but celecoxib attenuated decreases in MVC 4-h post exercise (p < 0.05). This study suggests that athletes may not benefit from prophylactic ibuprofen or flurbiprofen treatment to prevent discomfort or performance decrements associated with exercise, but celecoxib may mitigate short-term performance decrements. [ABSTRACT FROM AUTHOR]

The practical applications of magnesium (Mg) alloys are usually beset by their relatively low strength and limited ductility. Herein we attempt to fabricate hexagonal BN nanoplatelet (BNNP) reinforced ZK61 magnesium composites using a combination of spark plasma sintering and friction stir processing. The resulting composites exhibit microstructural characteristics of homogeneous dispersion of BNNP in Mg matrix with refined equiaxed grains and (0002) basal texture roughly surrounding the pin column surface. Transmission electron microscopy observation illustrates that trace amounts of Mg 3 N 2 and MgB 2 form at BNNP-Mg interface, in which Mg 3 N 2 locates at the basal plane of a BNNP and MgB 2 grows at its open edge. The spatial distribution of Mg 3 N 2 and MgB 2 facilitates interfacial wetting and stronger BNNP-Mg interface in such a way that interfacial products act as anchors bonding between them. In comparison with monolithic ZK61 alloy, the BNNP/ZK61 composites display simultaneous improvements in yield strength, hardness and ductility, achieving good strength-ductility balance. This research is expected to shed some light on BNNP potentials for designing and producing magnesium composites with high strength and good ductility. [ABSTRACT FROM AUTHOR]

Anatomic (aTSA) and reverse total shoulder arthroplasty (rTSA) are well-established treatments for patients with primary osteoarthritis and an intact cuff. However, it is unclear whether aTSA or rTSA provides superior outcomes in patients with preoperative external rotation (ER) weakness. A retrospective review of a prospectively collected shoulder arthroplasty database was performed between 2007 and 2020. Patients were excluded for preoperative diagnoses of nerve injury, infection, tumor, or fracture. The analysis included 333 aTSAs and 155 rTSAs performed for primary cuff-intact osteoarthritis with 2-year minimum follow-up. Defining preoperative ER weakness as strength <3.3 kilograms (7.2 pounds), 3 cohorts were created and matched: (1) weak aTSAs (n = 74) vs. normal aTSAs (n = 74), (2) weak rTSAs (n = 38) vs. normal rTSAs (n = 38), and (3) weak rTSAs (n = 60) vs. weak aTSAs (n = 60). We compared range of motion, outcome scores, strength, complications, and revision rates at the latest follow-up. Despite weak aTSAs having poorer preoperative strength in forward elevation and ER (P <.001), neither of these deficits persisted postoperatively compared with the normal cohort. Likewise, weak rTSAs had poorer preoperative strength in forward elevation and ER, overhead motion, and Constant, Shoulder Pain and Disability Index, and University of California, Los Angeles scores (P <.029). However, no statistically significant differences were found between preoperatively weak and normal rTSAs. When comparing weak aTSA vs. weak rTSA, no differences were found in preoperative and postoperative outcomes, proportion of patients achieving the minimal clinically important difference and substantial clinical benefit, and complication and rate of revision surgery. In preoperatively weak patients with cuff-intact primary osteoarthritis, aTSA leads to similar postoperative strength, range of motion, and outcome scores compared with patients with normal preoperative strength, indicating that preoperative weakness does not preclude aTSA use. Furthermore, patients who were preoperatively weak in ER demonstrated improved postoperative rotational motion after undergoing aTSA and rTSA, with both groups achieving the minimal clinically important difference and substantial clinical benefit at similar rates. [ABSTRACT FROM AUTHOR]

Biological materials exhibit complex structure-property relationships which are designed by nature's evolution over millions of years. Unlocking the fundamental physical principles behind these relationships is crucial for creating bioinspired materials and structures with advanced functionalities. The eggshell is a remarkable example with a well-designed structure to balance the trade-off as it provides mechanical protection while still being easy for hatching. In this study, we investigate the underlying mechanical design principles of chicken eggshells under various loading conditions through a combination of experiments and simulations. The unique geometry and structure of the eggshell play a critical role in achieving an excellent balance between mechanical toughness and ease of hatching. The effects of eggshell membranes are elucidated to tune the mechanical properties of the eggshell to further enhance this balance. Moreover, a mechanics-based three-index model is proposed based on these design principles, suggesting the optimal eggshell thickness design to improve survivability across a broad range of avian species with varying egg sizes. The survivability-design relationships hold great potential for the development of improved structural materials for applications in sports safety equipment and the packaging industry. The fundamental physical principles underlying the complex structure-property relationships in biological materials are uncovered in this study, with a particular focus on chicken eggshells as a prime example. Through the investigation of their mechanical design, we reveal the critical role of eggshell geometry and structure in achieving a balance between toughness and ease of hatching. Specifically, the crack resting effect is observed, making the eggshell easier to break from the inside than from the outside. Additionally, we explore the influence of eggshell membranes on this balance, contributing to the enhancement of the eggshell's mechanical properties. For the first time, we propose a three-index model that uncovers the underlying principles governing the evolution of eggshell thickness. This model suggests optimal thickness designs for diverse avian species, with the goal of enhancing egg survivability. These findings can guide the development of improved structural materials with advanced functionalities, enabling greater safety and efficiency in a wide range of applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Strength prediction under the action of pores is crucial for the safety of ceramics. Here, a quantitative prediction model of pore-strength response under mode-I loading was developed based on the new mapping relationship between stress intensity factor and tip radius. The new model was proved to have great application after comparison and analysis of the pore-strength test data of three typical ceramics as well as the pertinent data as-reported in the literature. Results indicated that when the tip radius of pore (ρ) exceeds the critical value (ρ c = K Ic 2/(π σ 0 2)), the stress intensity factor increases as a power function with increasing ρ , at which point the strength decay is significantly weakened, and when the ρ is lower than the ρ c , the pore can be equated to a crack problem. This work can not only forecast and assess the failure strength of ceramics containing pores, but also provide guidance for the design of extremely dependable ceramics. [ABSTRACT FROM AUTHOR]

A novel transient liquid phase bonding (TLP) method for obtaining high-temperature resistant diamond/Cu joint was designed. The joint was achieved through the isothermal solidification of Au–Si interlayer assisted by the diamond active modified layer and NiTi particles. The interfacial reaction mechanisms in the TLP process were systematically investigated in this study. The results shown that Ti 5 Si 3 C, CuTiSi and NiTiSi precipitated from the seam. Due to the precipitation of Si and the interdiffusion of Au–Cu, a ductile Au–Cu solid solution ((Au, Cu)ss) matrix formed. The shear strength of the diamond/Cu joint was notably affected by the holding time. The maximum room-temperature shear strength of 108 MPa was achieved when the joints were held at 600 °C for 60 min, and the high-temperature strength was still up to 22 MPa at 600 °C. The high strength of the joints was achieved because of (i) the elimination of the Cu(Au)–Si brittle phases, (ii) the NiTiSi whiskers pulling-out mechanism, and (iii) the moderate distribution of compounds at the diamond/seam interface. [ABSTRACT FROM AUTHOR]

Studies reported that knee extension strength on the operated side in patients with hip fractures was not recovered to the level on the non-operated side 6 months after surgery or later. In a cross-sectional study, we revealed that a reduction in isometric knee extension muscle strength on the operated side in patients with hip fractures approximately 6 months after surgery was associated with not only a reduction in skeletal muscle mass but also a reduction in muscle quality, characterized by a reduction in the phase angle (PhA). Furthermore, the mechanisms of knee extension strength improvement can be clarified in more detail using the minimal significant change as the index of recovery. However, no longitudinal studies have examined the factors for knee extension strength improvement based on the minimal significant change in patients with hip fractures 6 months after surgery. This study aimed to longitudinally examine the factors influencing the recovery of knee extension strength based on the minimal significant change in patients with hip fractures between 2 weeks and approximately 6 months after surgery. In this study, the outcomes used were basic and medical information, PhA, skeletal muscle index (SMI), pain, one-leg standing time, movement control during one-leg standing, and walking speed. For PhA, SMI, pain, one-leg standing time, movement control during one-leg standing, and walking speed, the amount of change was calculated by subtracting the data at 2 weeks from the data at 6 months. Group classification was determined by dividing the patients into two groups using a previous study as a reference: recovery group if the knee extension strength value approximately 6 months after surgery minus that 2 weeks after surgery was ≥3.3 kgf and non-recovery group if the value was <3.3 kgf. Logistic regression analysis was performed to explore the association between the recovery and non-recovery groups. The recovery group contained 55 patients, while the non-recovery group comprised 35 patients. The only significant factor associated with knee extension muscle strength in the recovery group was the amount of change in PhA. The odds ratio for the amount of change in PhA was 2.26. The discrimination rate of the model was 62.5%. Our results suggest that recovery of knee extension strength in patients with hip fractures after surgery was mainly because of improvements in muscle quality, not improvements in muscle mass or pain. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop new adhesive formulations that include natural polyphenols extracted from green tea (GTE), tricalcium phosphate (TCP) and chitosan to improve dentin bonding characteristics and cytotoxicity. Four experimental adhesives were formulated under laboratory conditions. The groups differed in the integration of either GTE and/or TCP + chitosan. The four experimental and one clinically proven reference adhesive underwent shear bond testing after 24 h and 6 months of aging (n = 200) with subsequent fractographic analysis. Bond morphology was analyzed under a scanning electron microscope. The presence of phenolic compounds was validated by high performance liquid chromatography. Cytotoxicity was assessed by the WST-1 colorimetric assay on eluates up to 6 months. Statistical analysis was performed by one- and three-way ANOVA, Games-Howell and Tukey's post-hoc test as well as multiple students t-tests (α = 0.05). Weibull analysis was further conducted. The addition of GTE into the bonding agent did show immediate (p = 0.023, p = 0.013) and long-term (p < 0.001) effects on bond strength. After 24 h, GTE doped groups performed equal to the reference (p = 0.501, p = 0.270) and TCP and chitosan displayed improvements in reliability (m=4.0, m=4.3). Bond strength is retained after aging by adding GTE (p = 0.983). The additional presence of TCP and chitosan reduces it (p = 0.026). Excluding cohesive and mixed failures, the reference adhesive performed statistically equal to three of the four experimental groups. No long-term cytotoxic effects were shown. The integration of GTE can enhance bond strength and a calcium source helps to improve immediate bond reliability. • Synthesis of adhesives containing polyphenols, tricalcium phosphate and chitosan. • Similar bond strength values compared to a gold standard control. • Improvement of bond strength by natural polyphenols. • Improvements of bond reliability by tricalcium phosphate and chitosan. [ABSTRACT FROM AUTHOR]

Yield phenomena and bending strength of single crystal 8YSZ were evaluated using microcantilever beam specimens with various crystal orientations. Nonlinearity due to plastic deformation was observed in the stress-strain curves, and the yield stress was found to depend on the crystal orientation. TEM observation revealed many areas of disordered lattice in the region where the maximum tensile stress occurred. Resolved shear stress (RSS) was analyzed for the primary {001}<110> and the secondary {110} < 1 1 ̅ 0 > and {111} < 1 1 ̅ 0 > slip systems as a function of the angle between the specimen's longitudinal direction and the [001] orientation, indicating that the RSS for the secondary ones was the critical RSS in the angle at 10 ° or lower while that for the primary one did so at 20 ° or higher. The measured bending strength, which depended on the crystal orientation, was lower than, but on the same order of magnitude as, the ideal strength. [ABSTRACT FROM AUTHOR]

This research article investigated the stress-state and strain-rate-dependent mechanical properties and failure of alumina ceramic. Compression–shear testing was carried out using a split-Hopkinson pressure bar under equivalent strain rates ranging from 1 0 1 s−1 to 1 0 3 s−1. Ultra-high-speed images coupled with digital image correlation were used to investigate the in situ time-evolving strain field and the failure process (e.g., crack growth). Experimental results showed equivalent strength reduced from 4.27 ± 0.23 GPa for the uniaxial compression tests to 3.75 GPa and 2.00 GPa for compression–shear tests across the strain rates and shear angles (5 ° to 25 °), with the strength decreasing with an increasing shear angle. The crack speed ranged from 908 m/s to 3208 m/s across the range of strain rates and shear angles, with a positive correlation noted for crack speeds with strain rate and increasing sensitivity with an increasing shear angle. The extent of localization of shear strain in alumina under compression–shear deformation was observed to be strain-rate-dependent, and it increased with an increasing strain rate of deformation. Furthermore, axial and shear strain localization increased with the increasing shear angle, contributing to local shear failure before the complete failure of the specimen. Overall, this paper provides new insights and measurements of the strain-rate-dependent and shear-dependent strength and crack speeds of alumina under compression–shear loading, and these serve as vital inputs for future computational model development and validation. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a neurological disease characterized by demyelination disrupting the central nervous system. Persons with MS may exhibit symptomatic strength asymmetry (SA) that impacts motor gait and ankle mobility. The purpose of the present study was to investigate ankle dorsiflexion SA in people with MS and its relationship to functional performance. Is their a difference in dorsiflexion SA in MS participants compared to healthy individuals and does it impact functional performance? 13 MS participants (EDSS 3.5 + 1.8) and 13 age matched NON-MS participants underwent maximal isometric (MVC) dynamometry testing for ankle dorsiflexion in both limbs to determine SA. Participants performed three functional tasks of walking performance. There was a significant intra-limb MVC difference in the MS group, and significantly greater isometric SA (p < 0.007) and isokinetic SA (p < 0.04) in the MS group compared to healthy individuals. The MS group exhibited significant correlations between outcomes of functional walking performance with isokinetic but not isometric SA. There was no significant correlation between disability status and functional task performance. A nkle dorsiflexion SA is negatively correlated with functional performance in MS participants. MS disability status was not a predictor of functional task performance, and symptom testing may be appropriate to assess walking ability in persons with MS. • Isokinetic asymmetry correlates with walking tests. • Multiple sclerosis exhibit significant asymmetry. • Multiple sclerosis exhibit slower walk speed. • Asymmetry in multiple sclerosis is greater than healthy individuals. • Isometric and isokinetic strength asymmetry is exhibited in multiple sclerosis. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare muscle strength, balance, and physical activity between children with chronic ankle instability and copers. Cross-sectional study. Pediatric Physical Therapy laboratory. Children aged between 7 and 12 years old from regular schools who had a history of unilateral ankle sprain. Lower extremity strength, Static and dynamic standing balance, and Level of physical activity. Fifteen children with chronic ankle instability and 15 copers were recruited. Demographic data showed no differences between group except for sex and the Cumberland Ankle Instability Tool-Youth (CAITY) score. Children with CAI had a significantly lower score during the standing long jump test (p < 0.05), poorer performance of single leg stance test (p < 0.001) and Y-Balance test in the anterior, posteromedial, and posterolateral directions (p < 0.05) when compared to copers. Total METs per week was significantly higher in the copers (p < 0.05). Children with chronic ankle instability exhibited weaker lower limb strength, poorer static and dynamic standing balance, and participate in less physical activity compared to those in a coper group which may have future negative health consequences. Knowledge about the differences between the two groups may provide guidance for physical educators and physical therapists. (200 words) • Children with ankle sprain can further develop to either copers or non-copers • Non-copers exhibited weakness, poor standing balance, and low physical activity • Findings raised awareness of prevention of negative consequences in non-copers [ABSTRACT FROM AUTHOR]

• Compared with a non-exercising control group, resistance training consistently improved muscle mass, strength and physical function. • Resistance training volume (number of sets) and muscle action type impacted increases in skeletal muscle mass. • Resistance training volume (number of sets), load, weekly frequency, and exercise order impacted increases in muscular strength. • Inter-set rest, periodization, set end point, contraction velocity/time under tension, and set configuration did not appear to affect increases in skeletal muscle mass and muscular strength. • Limited data impeded our ability to determine the impact of several resistance training prescription variables on physical function. The aim of this umbrella review was to determine the impact of resistance training (RT) and individual RT prescription variables on muscle mass, strength, and physical function in healthy adults. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass (or its proxies), strength, and/or physical function in healthy adults aged >18 years. We identified 44 systematic reviews that met our inclusion criteria. The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews; standardized effectiveness statements were generated. We found that RT was consistently a potent stimulus for increasing skeletal muscle mass (4/4 reviews provide some or sufficient evidence), strength (4/6 reviews provided some or sufficient evidence), and physical function (1/1 review provided some evidence). RT load (6/8 reviews provided some or sufficient evidence), weekly frequency (2/4 reviews provided some or sufficient evidence), volume (3/7 reviews provided some or sufficient evidence), and exercise order (1/1 review provided some evidence) impacted RT-induced increases in muscular strength. We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass, while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass. There was insufficient evidence to conclude that time of day, periodization, inter-set rest, set configuration, set end point, contraction velocity/time under tension, or exercise order (only pertaining to hypertrophy) influenced skeletal muscle adaptations. A paucity of data limited insights into the impact of RT prescription variables on physical function. Overall, RT increased muscle mass, strength, and physical function compared to no exercise. RT intensity (load) and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy. RT volume (number of sets) influenced muscular strength and hypertrophy. [Display omitted] [ABSTRACT FROM AUTHOR]

Concrete has experienced significant improvements in recent decades, resulting in lower Portland cement consumption as well as a lower carbon footprint through CO2 injection while keeping comparable fresh, mechanical, and durability performance. The use of CO2 injection in concrete (CarbonCure) in the United States and Canada has enabled advances such as green concrete under normal and severe conditions. While incorporating novel developments, this study focuses on CarbonCure concrete modification in the extreme weather of the Arabian Gulf region. This is a relatively new option that has entered the field in the Middle East. The materials, process, and fresh and hardened properties of the CarbonCure concrete made and field cured in the Arabian Gulf region will be considered here and evaluated in detail. Along with adding CO2 to the mix, the cementitious material was lowered without impacting the quality or performance of the structural concrete. The developed green mix included up to 0.2% CO2 by mass of cementitious material. Because of the benefit of early carbonation, which strengthened the concrete product even with less cementitious material, this green concrete mix retained a 28% increase in slump compared to the standard concrete mix without CO2, a 28-day compressive strength of 48 MPa, low water absorption of 1.3%, and resistance to aggressive chemicals, all within the limits defined by the standard codes. Due to these benefits, and because this green concrete was tested against the severe coastal climate, it would be ideal for maritime applications. [ABSTRACT FROM AUTHOR]

The cement industry ranks as one of the most significant contributors to carbon emissions among industrial sectors globally. Carbon dioxide (CO2) emissions have the potential to lead to considerable health and economic concerns. CO2 is the second-leading gas after steam, in creating the greenhouse effect. A significant percentage of CO2 emissions in cement plants come from the calcination of limestone to produce clinker. This study examines the impact of partially substituting ordinary Portland clinker with basaltic rocks on the characteristics of the resulting cement. These are employed to mitigate the impact of environmental contamination (CO2 emissions). The studied basaltic rocks were tested to determine the optimal weight percentage replacement. Five mixtures were produced through the partial substitution of clinker with varying proportions of basaltic rocks (10%, 15%, 20%, 25%, and 30%). An investigation was carried out to examine the impact of basaltic rocks on various properties of the produced cement, including workability, setting time, and strength. The parameters were investigated and evaluated by carrying out tests on fresh and hardened mortar specimens at specific time intervals. The results of the investigation lead to the conclusion that the ideal suggested proportion of the studied basaltic rocks as a partial substitute for ordinary Portland clinker is 15%. [ABSTRACT FROM AUTHOR]

SiC reticulated porous ceramic with excellent strength and high-density ceramic struts was successfully prepared using the polymer replica method, followed by pressureless sintering under a buried charcoal atmosphere. First, a polyurethane (PU) template was coated with a Si slurry and then a SiC-containing slurry, and subsequently heated under the buried charcoal atmosphere. To ensure excellent coating ability of the slurries, the viscosity, thixotropy, and yield stresses of the Si slurry were optimized by adjusting the content of the thickening agent. During heating, Si in the coating layer reacted with the residual C and CO gas from the PU template and buried charcoal, forming SiC whiskers that filled hollow voids within the SiC struts. Additionally, catalyst ferric nitrate was added to the Si slurry to promote the generation and growth of SiC whiskers. As a result, when compared to the untreated SiC reticulated porous ceramic, the SiC reticulated porous ceramic pre-coated with Si layers exhibited significant improvements in mechanical strength and thermal shock resistance, despite minor differences in porosity. Furthermore, an industrial test conducted in the copper smelting industry showed that the structure of SiC reticulated porous ceramic, prepared in this study and used as filters, remained intact even after 7 days of continuous use. Meanwhile, a significant number of inclusions was adhered to the surfaces of the filters. Therefore, the processes combined with in-situ generation of SiC whiskers is an ideal and low-cost method for fabricating SiC filters with excellent properties. [ABSTRACT FROM AUTHOR]

In this study we first investigated the strength of grains, i.e., single crystals, and grain boundaries (micro-scale strength) of hydroxyapatite ceramics in different crystal orientations, using microcantilever bending tests. The specimens were prepared from two types of hydroxyapatite ceramics; one is that with uniaxially aligned c -axes of grains and the other with randomly oriented ones. Both the grain and grain boundary strengths were slightly higher in tensile stress application parallel to c -axis than in the perpendicular in the aligned material. These strengths, however, were substantially higher than those of the randomly oriented one. Then, three-point bending tests were conducted to determine the polycrystalline strength (macro-scale strength) for the above two types of hydroxyapatite ceramics. While the strength values were comparable in tensile stress applications parallel and perpendicular to c -axis in the aligned material, that of the randomly oriented one is again significantly lower than them. In particular, the strength of the grain boundary was higher when the angle between the c -axis of the two hydroxyapatite grains divided by the boundary was close to 0 or 90°. The effects of the grain orientation and alignment on the mechanical properties were discussed on the basis of both the micro-scale and macro-scale results. These results indicate that selective formation of high-strength grain boundaries due to c -axis alignment of hydroxyapatite grains is effective in improving the mechanical properties of bulk ceramics, such as macroscopic strength and fracture toughness. [ABSTRACT FROM AUTHOR]

MgO-MgFe 2 O 4 refractory aggregates with high closed porosity were fabricated using MgO agglomerates and Mg(OH) 2 with introducing Fe 2 O 3 additive. The evolutions of pores and microstructure and their relationship with the properties of the specimens were studied. The addition of Fe 2 O 3 obviously promoted the MgO grain growth and conversion of large open pores into small closed pores, attributing to the formation of cationic vacancies and intergranular MgFe 2 O 4 bonding phase. Owing to the presence of closed pores and networks of intergranular MgFe 2 O 4 , both thermal insulation and strength were enhanced significantly. Besides, the formed closed pores and MgFe 2 O 4 phase could accommodate thermal stress and induce transgranular fracture and crack deflection, therefore effectively improving the thermal shock resistance. The specimen with 15 wt% Fe 2 O 3 showed a apparent/closed porosity of 0.7%/10.1%, median pore diameter of 4.37 µm, thermal conductivity of 9.3 W/(m·K) (500 °C), flexural strength of 143.5 MPa, and residual flexural strength of 24.1 MPa after thermal shock. [ABSTRACT FROM AUTHOR]

The threat of emerging infectious diseases has highlighted the need for effective gowns to protect health care workers and patients. Although studies identified end user issues with the physical performance of gowns, the literature that evaluates the performance is scarce. This paper represents 1 of the first efforts to investigate the physical performance of a substantial set of isolation gown models in the marketplace. Physical performance of 20 commercial and 2 experimental disposable isolation gowns was evaluated in this study. Standard test methods were used to investigate a range of properties, including thickness, weight, tensile strength, tearing strength, and seam strength. In general, due to the differences in the fibers and methods used for the construction, large variations in the tensile, tear, and seam strength results were found. When the gowns were compared to their respective Association for the Advancement of Medical Instrumentation PB70 protection levels, no clear trend was found between protection levels and tear strength or between protection levels and seam strength, while there was a linear relationship between gowns' Association for the Advancement of Medical Instrumentation PB70 levels and their tensile strength. It was found that fabric construction significantly affects the physical performance of gowns. Based on this work, a new standard, American Society of Testing and Materials International F3352, was published and has been recognized by the Food and Drug Administration. American Society of Testing and Materials International F3352 is expected to help end users in selecting the appropriate protective clothing. • Physical performance is critical for the protection of health care workers. • This study evaluated the tensile, tear, and seam strength of isolation gowns. • Large variations in the tensile, tear, and seam strength results were found. • A new standard was established based on the findings. • This standard is expected to help end users in selecting appropriate gowns. [ABSTRACT FROM AUTHOR]

The physical and chemical characteristics of the clay are highly dependent on the geospatial conditions. Clays procured from three geospatially distinct locations (Raithal in Jalore District, Rajasthan, India; Gajsinghpura and Jheepasani in Jodhpur District, Rajasthan, India) near the edge of the Thar Desert in India have been used in this study. Frustum-shaped 3L green composites were prepared by a three-step process by mixing clay and sawdust in equal volume fractions, similar to local G-filters in India. Here, green composites were sinter-fused at various temperatures to create ceramic water filters. Raithal and Gajsinghpura clay-based ceramics showcased similar behavior in grain length variation while being sintered at 650°C, 750°C, and 850°C, respectively. Further, the pore dimensions, thermal stability, fracture toughness, and flow characteristics of these ceramic water filters baked at 750°C were studied. The gravity-based cumulative water discharge rate proportionally increased with the pore surface area of distinct ceramics from different locations. Micro-CT (3.4 m resolution) data visually confirms that Gajsinghpura clay has a rigid structure with a large pore volume. Results from thermogravimetric analysis showcase the reorganization of the gibbsite layer in Jheepasani clayey soils. Crystalline and amorphous characteristics were observed from micrographs of Gajsinghpura and Raithal ceramic samples. Raithal clay ceramic frustum bases were the toughest. Gajsinghpura and Raithal clay-based ceramic filters show similar behavior in Escherichia coli removal as a function of average pore diameter. [ABSTRACT FROM AUTHOR]

In this study, the effect of the alumina particle size on the formation of mullite using a silica gel powder and micro- and nano-scale Al 2 O 3 powders as raw materials was investigated. The optimized Al 2 O 3 source was then reacted with the silica gel to prepare porous mullite-based ceramics. The results revealed that the highly reactive nano-Al 2 O 3 powder could form mullite at a relatively low firing temperature. Therefore, the nano-Al 2 O 3 powder was used to prepare porous mullite-based ceramics by firing at 1600 °C, 1650 °C and 1700 °C. The pore size of the prepared porous mullite-based ceramics ranges from tens to hundreds of micrometres, with the apparent porosity being 42.8–58.0%. Further, the mullite content in the samples increased with increasing firing temperature, and a higher firing temperature promoted sintering, resulting in improved strength of the sample. After calcination at 1700 °C, the mullite content in the sample reached 81.8%, and the sample showed excellent thermal shock resistance. The strengths of the samples before and after thermal shock were found to be 23.6 and 15.58 MPa, with the residual strength ratio being 66%. [ABSTRACT FROM AUTHOR]

In this work, a solid YAG polymer precursor was synthesized. And the YAG ceramic fiber with the highest tensile strength of 1.56 GPa and modulus of 252 GPa was fabricated. The green fiber with a uniform diameter of 16 μm was sintered to 600 °C in steam to obtain inorganic fiber. The crystal-form transition and the crystal size during the sintering process from 900 °C to 1500 °C were investigated by in-situ XRD. The ceramic fibers were sintered at different temperatures to obtain ceramic YAG fiber. The YAG fiber produced at 1100 °C exhibited the maximum tensile strength owing to its small diameter of 10 μm, small particle size of 23 nm, and compact microscopic structure. Due to its tiny diameter, the prepared YAG ceramic continuous fiber is soft enough to be woven into the fabric, making it promising in use. [ABSTRACT FROM AUTHOR]