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Amorphous solids are known to fail catastrophically via fracture, and cavitation at nano-metric scales is known to play a significant role in such a failure process. Micro-alloying via inclusions is often used as a means to increase the fracture toughness of amorphous solids. Modeling such inclusions as randomly pinned particles that only move affinely and do not participate in plastic relaxations, we study how the pinning influences the process of cavitation-driven fracture in an amorphous solid. Using extensive numerical simulations and probing in the athermal quasistatic limit, we show that just by pinning a very small fraction of particles, the tensile strength is increased, and also the cavitation is delayed. Furthermore, the cavitation that is expected to be spatially heterogeneous becomes spatially homogeneous by forming a large number of small cavities instead of a dominant cavity. The observed behavior is rationalized in terms of screening of plastic activity via the pinning centers, characterized by a screening length extracted from the plastic-eigenmodes. [ABSTRACT FROM AUTHOR]

High-entropy alloys possess significant potential for material applications in demanding structural components subjected to extreme conditions. Through experimental investigations, we have validated that the CoCrFeNiAl0.1Ti0.05 high-entropy alloy, which was fabricated using a cold rolling and annealing process, exhibits an excellent balance of strength and ductility at 77 K. Specifically, it demonstrates a yield strength of 575 MPa, a tensile strength of 1145 MPa, and a ductility of 55%. This enhanced performance can be attributed to the altered deformation mechanism at low temperatures, leading to the multiplications of stacking faults and twins. Additionally, the introduction of small quantities of aluminum and titanium results in the formation of precipitated phases within the alloy matrix. The synergistic influence of these two factors contributes to the augmentation of cryogenic plasticity in the alloy. [ABSTRACT FROM AUTHOR]

Metals often lose their ductility at cryogenic temperatures owing to the decreased mobility of dislocations. TRansformation-induced plasticity (TRIP), a toughening mechanism at room temperature, can increase damage susceptibility at low temperatures, as the resultant martensite phases can become more brittle than the parent phases. Herein, we develop a high-entropy alloy (HEA) with an improved low-temperature impact-damage tolerance through a sequential plasticity mechanism. We design a trip-assisted dual-phase HEA (TADP HEA) and investigate the effects of Al addition on its mechanical properties upon deformation at different temperatures, depending on stacking fault energy (SFE). Our analysis shows that a senary (Cr20Mn6Fe34Co34Ni6)98Al2 HEA exhibits superior mechanical properties, including a 641 MPa yield strength (σy), 964 MPa ultimate tensile strength (σUTS), and 40% uniform elongation (ɛUTS) at ambient temperature (25 °C), and a 1 GPa σy, 1.5 GPa σUTS, and 36% ɛUTS at −100 °C. Notably, despite the presence of hexagonal-close packed martensite, the HEA exhibits a higher Charpy impact energy (406 J) than Cantor HEA (344 J) at −100 °C. We attribute this improvement to the sequential deformation mechanism of mechanical twinning and martensitic transformation in the HEA at −100 °C, which results in sustainable steady strain-hardening during deformation. We suggest that optimizing the sequential deformation mechanism by manipulating SFE in multi-component alloys can be an effective route for improving the damage tolerance of metals at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Lattice distortion is considered to be one of the four core effects in a multicomponent high-entropy alloy. However, their effect is least understood from experiment and theoretical standpoints. The present investigation revealed a unique way to understand this effect by combining experiments with density functional theory (DFT) calculations. A small amount of Al and Si were carefully added to the whole-solute matrix of Cantor alloys. The different-sized atomic species introduces a huge lattice distortion in the matrix, leading to a simultaneous improvement in yield strength (YS), ultimate tensile strength (UTS), and percent elongation. An extensive DFT simulation indicates that a lattice distortion is prominent in an Al-containing alloy, whereas Si does not induce a lattice distortion. However, Si leads to severe interlayer lattice distortion, caused by the displacement of Si, during twinning. This leads to the improvement of YS, UTS, and ductility. Lattice distortion and its variants play significant effects on the mechanical properties of high-entropy alloys (HEAs) in terms of local lattice distortion, providing an uneven energy landscape for the movement of line defects or interlayer distortion. The inherent nature of local lattice distortion in HEAs leads to the wavy or tortuous dislocation, unlike a straight dislocation in conventional alloys. The movement of the wavy type of dislocation through a distorted or defective lattice requires large stress, resulting in a pronounced effect on solid solution strengthening. This local lattice distortion also dictates the degree of the interlayer distance distortion in the vicinity of atoms, leading to an increase or decrease in stable stacking fault energy that decides the deformation mode via slip or twinning. [ABSTRACT FROM AUTHOR]

In this work, the incorporation of halloysite nanotubes (HNTs) and polyphenylene ether-grafted maleic anhydride copolymer (FB) into acrylonitrile butadiene styrene (ABS)/polyphenylene oxide (PPO) blend has been investigated to enhance the compatibility and performance of the blends. ABS/PPO blend (AP) with the weight ratio of ABS/PPO = 70/30 with 5 wt% loading of FB and different weight contents of HNTs were elaborated by melt blending process, and their properties were studied. The SEM observation revealed that AP blend exhibited dispersed phases of PPO droplets with apparent gaps between PPO and ABS phases, indicating poor adhesion between the polymers in the blend. As the compatibilizer, FB effectively enhanced the inter-phase interaction, minimizing the formation of interfacial gaps, evidenced by the SEM images, leading to the adhesion between ABS, PPO, and HNTs phases. As a result, the mechanical performance of the AP blend was significantly improved with the addition of FB and HNTs. At 5 wt% of HNT, the AP/FB/HNT blend exhibited the tensile strength of 37.47 MPa and flexural strength of 59.09 MPa compared to 26.60 MPa and 39.45 MPa of neat AP, respectively. The glass transition temperature of the modified blends showed shifts compared to the neat AP, which indicates the improvement in miscibility of the modified-AP blends. The thermal stability and flame resistance of the blends were also enhanced with the introduction of HNTs and FB, evidenced by the V-1 rating in the UL-94 test and the increase in limiting oxygen index (LOI). These results demonstrated that the incorporation of HNTs and FB is a promising and straightforward method to improve the properties of ABS/PPO blends. [ABSTRACT FROM AUTHOR]

The difficulties in establishing an analytical model for plain woven fabric composites (PWFC) and its implementation are well-accepted due to the complexity of yarn architecture, approximations assumed, and lack of experimental validations. In this paper, a practical engineering approach is proposed to predict the tensile properties of PWFC. The approach assumes PWFC as cross-ply, the undulation angle an elliptical shape. The approach tremendously simplifies the calculation keeping a close agreement with the tensile experimental results of PWFC. The approach is remarkably compatible with other theoretical models and experiments that existed in the literature. [ABSTRACT FROM AUTHOR]

The construction of lunar stations for research and habitation requires high-performance building materials that can adapt to the harsh lunar environment. One of the feasible building materials is fiber-reinforced composites, for which the composition of glass fibers can be designed like lunar soils, i.e., terrestrial basalt, and in turn the "lunar glass" can be drawn into fibers. Because of a wide variation of TiO 2 in lunar soils, our study focused on a series investigation on the effect of TiO 2 (0.55 wt%-6.14 wt%) on fiber spinnability and strength of the simulated "lunar glass and glass fibers". The baseline glass composition was derived from a simulated TiO 2 -lean lunar soil and other glasses were made at different TiO 2 doping levels. The addition of TiO 2 was found to reduce the thermal stability of the melt, there appears a TiO 2 threshold (6.14 wt%), at which fibers cannot be drawn without breakage because of melt devitrification. The fiber tensile strength exhibits a nonlinear characteristic with an apparent maximum at 1.52 wt% TiO 2. FTIR and Raman spectroscopic studies were carried out to investigate the glass network structure responses to TiO 2 modifications and show TiO 2 functions as a network modifier, depolymerizing the silicate network. Statistical structure (FTIR & Raman based)–property modeling was attempted to further elucidate the effect of TiO 2 -induced structure change on T g and fiber tensile strength. Good agreements were found between the model predictions and the measured values. [ABSTRACT FROM AUTHOR]

In this work, the three‐dimensional stability of deep tunnel faces is evaluated in rock masses characterized by the generalized Hoek–Brown (H–B) criterion from the perspective of the limit analysis theorem. Considering that underground engineering is gradually developing towards larger burial depths and larger sizes, and the tensile strength of rocks is usually overestimated, the concept of tension cutoff (T‐C) is introduced to substitute the parabolic form of the H–B envelope in the tensile region with a circular arc. The multitangent technique is used to piecewise approximate the H–B envelope, instead of the conventional linear substitution, accounting for the nonlinear dependence of the shear strength on the pressure. Meanwhile, the earthquake loading is considered by the classic pseudostatic method. The tunnel face stability is measured by a stability number, which is calculated based on a newly developed multicone failure mechanism. Parameter studies indicate that the T‐C has almost no impact on the critical support pressure, while has a significant effect on the critical stability number, especially in the presence of earthquakes. Nearly all stress points back‐calculated from the rupture angles fall within the T‐C region, except for the first stress point associated with the first segment. Interestingly, the influence of the geological strength index (GSI) on the face stability is inverse to that of mi due to the brittleness of rocks. Moreover, the critical stability number is not sensitive to mi, but sensitive with the introduction of earthquake loadings. [ABSTRACT FROM AUTHOR]

The in-situ TiB whiskers (TiBw)-reinforced TC18 composite was fabricated using spark plasma sintering (SPS), then the effects of solution and aging treatment (2HT), solution and two-step aging treatment (3HT) on the microstructure and mechanical properties of the composite were investigated, respectively. The results showed that the α-phase microscale concentration control can be successfully achieved by different heat treatments. Concretely, a large amount of rod-like α-phase (α p) and needle-like α-phase (α s) were precipitated during the 2HT process. After the 3HT, the coarser α p formed a dense micro-network structure in the composite, while αs disappeared. Compared to the TiBw/TC18 composite, the ultimate tensile strength (UTS) of the 2HT composite increased by 11%, which is the result of the dense α s and α p co-hindering the dislocation movement, and the ductility of the composite increased by 221% after 3HT, which is the result of the coarsened α p blunting the crack tip, consuming the crack expansion energy and slowing down the crack expansion rate. By designing different heat treatment processes, this study aims to guide the suitability of TC18 composites under different working conditions. [ABSTRACT FROM AUTHOR]

Environmental friendly biocomposites are urgently needed to mitigate the pollution caused by huge consumption of petroleum-based polymers. Renewable carrageenan and polylactic acid (PLA) natural polymers have the potential to replace petroleum-origin polymers. Nevertheless, the carrageenan and PLA themselves inherit poor tensile strength, hydrophobicity and stability. The aim of this study is to underpin the mechanism of synthesis of carrageenan-PLA biocomposite using van't Hoff plot, 1HNMR and density functional theorem simulation. Strong hydrogen bonding was found at 1.88 Å between O atom (carrageenan) and H atom (PLA) and was validated in 1HNMR shifting at 5.3 ppm corresponding to –OH group from PLA. The interaction established in the biocomposite mixed at 50 °C leads to a stronger tensile strength of 75.37 MPa, higher hydrophobicity and thermal stability with highest activation energy of 45.39 kJ/mol. The biocomposite produced from renewable carrageenan-PLA material would be a future replacement for nondegradable plastic as a food packaging material. [ABSTRACT FROM AUTHOR]

Using cellulosic micro/nanofibrils (MFC/NFC) in developing films for coatings and packaging has aroused industrial interest to replace plastic. This study proposes functionalizing packaging films composed of hybrid suspensions of 80 % titica vine (Heteropsis flexuosa) and 20 % Pinus to improve their mechanical properties. The MFC/NFC were produced by mechanical fibrillation and adding proportions of 1, 2.5, and 5 % of nanolignin, vegetal tannin, and synthetic termite saliva. Both suspensions had concentrations of 1 % (w/w). The MFC/NFC were evaluated for energy consumption, microstructural, and stability, while the films were for physical, optical, barrier, and mechanical properties. Films with nanolignin 2.5 % obtained lower WVP and degradation in water, with greater hydrophobicity and puncture strength. The treatment with tannin 1 % obtained higher density and lower porosity, while termite saliva 1 % presented higher tensile strength at around 53.1 MPa. The additives improved the quality index of the MFC/NFC (>51.1 points). It is concluded that adding different binders can help expand the use of MFC/NFC. New studies are essential to seek pre-treatments or alternative fibrillation methods to increase their application and efficiency for fiber cell wall fibrillation, in addition to the need for a deeper analytical understanding of the interactions of additives with cellulose. [ABSTRACT FROM AUTHOR]

This study investigates the correlation between various micromagnetic signature patterns and the yield and tensile strengths of carbon steel (Cr12MoV steel as per Chinese standards). For this purpose, back-propagation neural network (BP-NN) models are established to quantitatively predict the yield and tensile strengths of carbon steels. The accuracy of prediction models is significantly affected by the presence of redundant micromagnetic signature patterns. By carefully screening the input parameters, it is able to effectively mitigate prediction errors arising from unreasonable model inputs. In the field of micromagnetic nondestructive testing (NDT), prediction models calibrated for a specific instrument or sensor cannot be directly applied to another instrument or sensor. In the study, a joint distribution adaptation transfer learning strategy based on auxiliary data is proposed to enhance the generalization of prediction models for cross-instrument applications. When auxiliary data accounts for 30% of the source domain data, the joint distribution adaptation transfer learning method based on auxiliary data improves the robustness of the model. The accuracy of the yield strength and tensile strength calibration models witnesses remarkable improvements of approximately 91.4% and 93.5%, respectively. [ABSTRACT FROM AUTHOR]

The design of stud connectors is aided by determining the relationship between shear strength and the input variables (number, diameter, height, tensile strength and elastic modulus of the studs, and compressive strength and elastic modulus of the concrete) that influence strength. Since strength is nonlinearly related to the influencing variables, which makes the predictions of the relevant empirical equations unreliable, the use of machine learning (ML) models is preferred. The prediction results of eight machine learning models were evaluated, including linear regression (LR1), ridge regression (RR), lasso regression (LR2), back-propagation artificial neural network (BP ANN), genetic algorithm optimized BP ANN (GA-BP ANN), extreme learning machines (ELM), random forests (RF), and support vector machines (SVM). The results show that the GA-BP ANN model is the most accurate model for prediction with a mean absolute percentage error (MAPE) of 6.17% and an R² of 0.9599. Based on the GA-BP ANN model and the global sensitivity analysis (GSA) method, a new parameter importance analysis method was developed to compare the magnitude of the effect of different input variables on strength. It was found that stud diameter had the greatest effect on shear strength. [ABSTRACT FROM AUTHOR]

To use Al composites in structural applications, we need to improve strength and ductility at the same time. In this article, we explore three main concepts to solve this problem: improving the dispersion uniformity of CNTs in Al powder without damaging its structure by solution coating technique, fabricating a hybrid composite by reinforcing Al with nano-TiC-CNT, comparing the properties of nano-TiC-CNT and micron-TiC-CNT hybrid composites. Microstructure observation by SEM, TEM, and XRD revealed well-dispersed and preserved CNTs without the formation of a second phase. The Al-0.5CNT composite showed good tensile strength and elongation at break of 278 MPa and 14%, respectively. Further improvements in tensile strength and ductility of 285 MPa and 23%, respectively, were measured after the addition of 2.5 wt%; (1.4 vol%) TiC nanoparticles to Al-0.5CNT composite. However, the introduction of 2.5 wt-% TiC macroparticles only improved the tensile strength by 48% but elongation at break was up to 32%. The improved strength and ductility are attributed to the introduction of geometrical necessary dislocation and Orowan looping of dislocations leading to back stress strengthening. The new Al composite is expected to find application in automotive and aerospace component manufacture and thermal management. [ABSTRACT FROM AUTHOR]

In the last two decades, several studies have been conducted for the process parametric optimization of fused filament fabrication (FFF) with a variety of thermoplastic composites, especially for mechanical properties. But hitherto less has been conveyed, on the development of dynamic reduced order models (ROMs) for digital twining (DT) of tensile properties (of 3D printed implants/scaffolds) with novel thermoplastic-based composites. In this study, for the generation of dynamic ROM (for hybrid analytics), the signal-to-noise (S/N) ratio was used to ascertain the best settings of parameters for tensile properties of polyvinylidene fluoride (PVDF) composite. The study suggests that the best setting of the FFF process, for the 3D printing of PVDF composite (90% PVDF, 8% hydroxyapatite (HAp), and 2% Chitosan (CS) (for maximizing the tensile properties as per ASTM-D638-Type-V) are nozzle temperature (NT) of 235°C, raster angle (RA) 45°, printing speed (PS) of 60 mm/s respectively resulting in peak load (PL) 394.87 N, peak stress (PSt) 33.92 MPa, Young's modulus (E) 2.606 MPa. For a modulus of toughness (MOT) of 0.484 MPa, the best settings are NT 230°C, RA 90°, and PS 50 mm/s. The results are supported by the morphological analysis. [ABSTRACT FROM AUTHOR]

This study aimed to develop environmentally friendly PVC composites for automotive by incorporating plantain fiber (PF) and calcite particles (CP) as reinforcements. Different weight percentages of PF and CP (ranging from 3% to 15%) were utilized. The mixtures underwent compounding and compression molding at 150°C for 10 min. The mechanical and thermal properties of the resulting composites were analyzed, and their fracture surfaces were examined using SEM. Results indicated that the inclusion of these reinforcements significantly enhanced the properties of the composites compared to unreinforced samples, with the hybrid composites exhibiting the best performance. Optimal compositions were identified within the range of 6-8 wt% PF and 3-4 wt% CP. The composite containing 6 wt% PF/3 wt% CP showcased the highest ultimate tensile strength (63.77 MPa), optimum elongation at break, and best insulating property (0.24 W/Mk). The composite with 8 wt% PF/4 wt% CP demonstrated the highest tensile modulus (4.79 GPa), flexural strength (91.35 MPa), and flexural modulus (8.2 GPa). Impact strength peaked at 10 wt% PF/5 wt% CP, reaching 107.02 J/m2. These findings indicate that the developed hybrid reinforced biocomposite compositions hold great promise for various automotive applications, including instrument panels, sun visors, headlining, seals, floor coverings, and protective strips [ABSTRACT FROM AUTHOR]

Biodegradable starch-based films are an environmentally friendly solution to reduce the use of petroleum-derived polymers. Thus, this work aims to obtain corn starch films by incorporating 5% w/w of cellulose nanocrystals (CNC), different concentrations of titanium dioxide nanoparticles (TiO2) (0, 0.25, 0.5, 1, and 2% w/w), and 40% w/w of glycerol and sorbitol (plasticizers), in a 1:1 ratio. The films showed a high potential for UV-light barrier, with an increase of 307% incorporating only 2 wt% of TiO2 in relation to the film without incorporation of TiO2. The use of TiO2 increased the white pigmentation capacity of the samples and decreased the lower water solubility – a reduction of approximately 28% using 0.5 wt% TiO2 compared to the CNC control sample was observed. The incorporation of TiO2 nanoparticles increased the tensile strength by adding 1 wt% of TiO2 nanoparticles with 34% increase in the tensile strength of the film without incorporation of TiO2. The thermal stability of the films with 1 wt% TiO2 and 5 wt% CNC increased by 85°C. Thus, the addition of CNC and TiO2 enabled an improvement in the physical/thermal/chemical properties of the films, making them possible alternatives for use in food packaging. [ABSTRACT FROM AUTHOR]

Cellulose nanofibrils (CNF) were esterified using long-chain fatty acid chlorides (octanoyl chloride, lauroyl chloride, and palmitoyl chloride) and composited with a biodegradable polymer, polybutylene succinate (PBS). The composite material was fabricated into nano-scale fibers and films via electrospinning and electrospraying processes using chloroform as a solvent. The influence of process conditions, CNF type and CNF amount on morphologies were investigated. The diameter of the electrospun fibers was ranged from 648 to 975 nm and fibers with the lowest diameters were produced at 10% concentration, 15 kV voltage and 30 µL/min flow rate. Further, PBS to CNF ratio of 95/5 and CNF esterified with lauryl chloride produced the best results. Electrospraying was achieved at a concentration of 5% or less and the tensile properties of the resulting electrosprayed films were investigated. The highest increase in tensile strength was observed at a PBS to CNF ratio of 99/1, while the most significant enhancement in elastic modulus occurred at the 95/5 ratio. [ABSTRACT FROM AUTHOR]

The fracture toughness (mode I) of shotcrete specimens was obtained using edge-notched partial disc (ENPD) specimens. Notched Brazilian discs (NBDs) were also tested to validate the results of the ENPD experiments. Numerical analysis was also conducted on the ENPD results to compare the measured and numerically obtained fracture toughness values. The notch lengths in the ENPD specimens were 15, 30, 45 and 60 mm, while the notch lengths in the NBD specimens were 10, 20, 30, 40, 50 and 60 mm. It was found that the flat joint model accurately predicted the potential crack growth path and crack initiation stress as compared with the experimental results. It was also deduced that the fracture toughness was roughly the same with an increase in the notch length. The tensile strength (σt) and fracture toughness (KIC) of the shotcrete specimens were found to be meaningfully correlated (σt = 7.92KIC). The ENPD tests yielded the lowest fracture toughness values because of the pure tensile stress distribution on the failure surface. It was also found that the derived fracture extension patterns from the laboratory investigations were in acceptable agreement with the outputs of numerical simulations. [ABSTRACT FROM AUTHOR]

Background/Aim: The interaction between the ethylene‐vinyl acetate (EVA) with distinct materials utilized for obtaining dental models can affect the performance of resulting mouthguards. This study attempted to evaluate the effect of different materials for conventional (dental stone) or 3D‐printed (resin) models on EVA's physical and mechanical properties and surface characteristics. Material and Methods: EVA sheets (Bioart) were laminated over four model types: GIV, conventional Type IV dental stone model (Zhermak); ReG, resin‐reinforced Type IV dental stone model (Zero Stone); 3DnT, 3D resin printed model (Anycubic) without surface treatment; 3DT, 3D‐printed model (Anycubic) with water‐soluble gel (KY Jelly Lubricant, Johnson & Johnson) coating during post‐curing process. The EVA specimens were cut following the ISO 37‐II standard (n = 30). Shore A hardness was measured before and after plasticization on the contact (internal) or opposite (external) surfaces with the model. The breaking force (F, N), elongation (EL, mm), and ultimate tensile strength (UTS, MPa) were measured using a universal testing machine. Macro‐photography and scanning electron microscopy were adopted for classifying the EVA surface alteration. Data were analyzed by one‐way ANOVA with repeated measures, followed by Tukey's test (α =.05). Results: Plasticization significantly decreased Shore A values for the tested EVA regardless of the model type (p <.001). Higher F, El, and UTS values were verified for the EVA with 3DT and GIV models compared to ReG and 3DnT (p <.001). 3DnT models resulted in severe surface alteration and a greater reduction of the mechanical properties of the EVA. Conclusion: The interaction of EVA with 3D resin‐printed models without surface treatment or resin‐reinforced Type IV dental stone models significantly affected the physical and mechanical properties of this material. The utilization of water‐soluble gel coating during the post‐curing process of 3D resin printed models improved the mechanical properties of the EVA, similarly when this material was plasticized over conventional Type IV dental stone model. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the effects of different surface treatments on the repair bond strength between a fiber‐reinforced dentin composite and a posterior composite. Methods: Forty fiber‐reinforced dentin composite resin blocks (4 mm × 4 mm × 4 mm) were separated into eight groups (n = 5) according to the surface preparation methods: (G1) negative control group, (G2) adhesive application, (G3) 50% dimethylsulfoxide (DMSO) application, (G4) 50% DMSO + adhesive application, (G5) 37% phosphoric acid etch + adhesive application, (G6) air abrasion + adhesive application, (G7) 37% phosphoric acid etch + 50% DMSO application + adhesive application, and (G8) air abrasion +50% DMSO application + adhesive application group. The composite surfaces were repaired in two layers with a posterior composite. Composite sticks were subjected to a micro tensile bond strength (μTBS) test. Fractured surfaces were evaluated using a stereomicroscope (×25). Short fiber‐reinforced composite samples' surfaces were investigated by scanning electron microscope (SEM). Shapiro Wilk, one‐way ANOVA, and Tukey HSD tests were used for statistical evaluation. Results: The highest average (μTBS) values were observed in G8, whereas the lowest mean μTBS values were evident in the G1 group. Statistically significant μTBS values were found in all adhesive‐applied groups when compared with the negative control group. Notably, the application of 50% DMSO without adhesive did not lead to a statistically significant increase in μTBS values. SEM images demonstrated that acid etching partially eliminated residues on the composite surface, while air abrasion had a detrimental effect on the integrity of fiber structures. Conclusion: In the repair of fiber‐reinforced dentin composite with a posterior composite, adhesive application is an effective approach. The treatment of 50% DMSO without adhesive did not confer a statistically significant advantage, and the supplemental use of acid etch or air abrasion did not show an additional benefit compared to adhesive‐only repairs. Clinical Significance: Adhesive application emerges as a potent and effective strategy for the repair of bur‐roughened fiber‐reinforced dentin composites. With its limitations, the study highlights the efficacy of adhesive‐only repairs without the necessity for additional surface treatments. [ABSTRACT FROM AUTHOR]

Objective: To measure degree of conversion (DC) of a flowable composite, microtensile bond strength (MTBS) to dentine in the snow‐plow technique with/without preheating and temperature in the preheated composite. Materials and Methods: For DC, snow‐plow specimens of Filtek Ultimate Flowable (Flow) and Filtek Bulk Fill (Bulk) (3M) were prepared by light‐curing composites simultaneously in standardized molds while in control groups light‐curing was separate. DC of Flow was measured using micro‐Raman spectroscopy. For MTBS, specimens were prepared on dentine of human extracted molars by simultaneous (snow‐plow) or separate (control) light‐curing. MTBS was measured using a universal testing machine after 24 h and 6 months. Data were analyzed using ANOVA with Tukey's post hoc (α = 0.05). Results: Increased curing time significantly increased DC in snow‐plow from 13.4% ± 11.6% (10 s) to 31.8% ± 4.4% (40 s) albeit significantly lower than controls (p < 0.05). Preheated Bulk improved conversion in snow‐plow (44.3% ± 1.7%) and control (50.5% ± 2.6%) (p < 0.05). No significant differences occurred in MTBS between groups (p > 0.05). MTBS values ranged between 66.7 ± 8.4 MPa (snow‐plow group_21°C_baseline) and 54.1 ± 15.8 MPa (control_21°C_long‐term). Temperature in the preheated Bulk dropped to ~38°C after 30 s. Conclusions: Snow‐plow technique, irrespective of preheating, resulted in lower DC of Flow than separate light‐curing of composite increments. Snow‐plow, irrespective of preheating, resulted in similar initial and long‐term MTBS to dentine. Clinical Significance: Clinicians with preference for flowable composite liners in Class II restorations should be aware that the snow‐plow technique of simultaneous light‐curing of flowable and bulk‐fill composite increments affects monomer‐to‐polymer conversion, albeit no effect on immediate, and long‐term bonding to dentine was detected. Preheating sculptable bulk‐fill composite improves conversion of the flowable liner in the snow‐plow technique but has no detectable effect on bond strength to dentine. [ABSTRACT FROM AUTHOR]

Novel alginate-based binders containing either catechol (d-Alg) or sulfonate (s-Alg) functional groups were developed and characterized to improve the capacity decay performance and better stability of Li-ion batteries. The electrochemical performance of silicon–graphite (Si/Gr) anode with alginate-based binders were compared to the commonly used CMC/SBR binder. The active material in the anodes was the ball-milled Si/Gr (20:80 wt%) powder mixture. A comprehensive electrochemical study was carried out through rate capability test, cycle test, differential capacity analysis (dQ/dV), and electrochemical impedance spectroscopy (EIS). The functionalized s-Alg binder showed the lowest electrolyte uptake (11.5%) and the highest tensile strength (97 MPa). Anodes with s-Alg exhibited high initial capacity (1250 mAh g−1) and improved decay performance (580 mAh g−1 at 0.2 C), by ~ 65% higher compared to CMC/SBR binder. The influence of pH value of s-Alg binder preparation showed that anodes prepared at pH 3 of s-Alg exhibit better performance, reaching 800 and 750 mAh g−1 at 0.1 and 0.2 C, respectively, due to the stronger bonding formation and compactness of anode layer which providing low charge transfer and solid electrolyte interface resistance. [ABSTRACT FROM AUTHOR]

This article aims to study the metallurgical and mechanical changes that occurred due to the T6 heat treatment of SiC particle-reinforced A356 matrix composite. The stir-casting technique was used for the fabrication of the composite. The fabricated composite was T6 heat-treated. Along with Mg2Si, MgAl2O4 a new phase, MgO was identified through energy dispersive X-ray spectroscopy mapping. An improvement in the mechanical properties was observed. All the mechanical properties are not equally influenced by T6 heat treatment. The formed phases act as strong obstacles to the slip and dislocation of the matrix which improves the ultimate tensile strength value by 40–42%, and impact strength 3 times higher than that of unheat-treated composite but only 10–12% improvement in hardness. [ABSTRACT FROM AUTHOR]

In this paper, the dispersion of Carbon nanomaterials (CNMs) in an electrolytic solution containing cations such as Ca2+, Al3+, Na+, and Mg2+ with different types of superplasticizers (Sika, Master Ease 3502, Prime DC, and Prime Flow) have been investigated. Further, the stabilized CNMs along with different superplasticizers (Sps) incorporated into the cementitious mortar and studied their mechanical strength. The influence of Sps on the stability of CNMs in an aqueous medium has been monitored by UV-Visible spectroscopy. The study concludes that Sika Sp was the best dispersant for the CNMs dispersion in an aqueous medium. The de-stability of the CNMs has followed this trend of the agglomerations in the electrolytic solution as Al3+>Ca2+>Mg2+>Na+. The Sika Sp has great dispersant properties as well as provides a homogeneous distribution of CNMs in a cementitious matrix which was supported by FE-SEM analysis. The addition of SIKA@PPC-GO (GO about 0.0015% by weight of cement) and SIKA@PPC-FCNTs (FCNTs about 0.0015% by weight of cement) results in enhancement of cement 11.67%, 8.73% for compressive and 26.35, 20.61% for tensile strength respectively, at the curing ages of 90 days. This investigation may provide advanced knowledge to predict the stability of CNMs in superplasticizer-based solutions. [ABSTRACT FROM AUTHOR]

Tendon allograft and xenograft processing often involves one or more steps of freezing and thawing. As failure strength is an important graft consideration, this study aimed to evaluate effects on failure properties when varying freeze‐thaw conditions. Kangaroo tendons, a potential xenograft source, were used to evaluate changes in ultimate tensile strength (UTS), failure strain and elastic modulus after exposure to different freezer‐storage temperatures (−20°C vs. −80°C), storage durations (1, 3, 6, 9, or 12 months), number of freeze‐thaw cycles (1, 2, 3, 4, 5, or 10), or freeze‐thaw temperature ranges (including freezing in liquid nitrogen to thawing at 37°C). Tendons stored for 6 or more months had significantly increased UTS and elastic modulus compared with 1 or 3 months of storage. This increase occurred irrespective of the freezing temperature (−20°C vs. −80°C) or the number of freeze‐thaw cycles (1 vs. 10). In contrast, UTS, failure strain and the elastic modulus were no different between storage temperatures, number of freeze‐thaw cycles and multiple freeze‐thaw cycles across a range of freeze and thaw temperatures. Common freeze‐thaw protocols did not negatively affect failure properties, providing flexibility for graft testing, storage, transportation and decellularisation procedures. However, the change in properties with the overall storage duration has implications for assessing the consistent performance of grafts stored for short versus extended periods of time (<6 months vs. >6 months), and the interpretation of data obtained from tissues of varying or unknown storage durations. [ABSTRACT FROM AUTHOR]