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Spinel saggar was prepared using Magnesium Aluminum spinel (MgAl 2 O 4), KF and TiO 2 as primary raw materials. The saggar's toughness was enhanced through in-situ generation of potassium titanate whisker (PTW). The impact of sintering temperature on the saggar's phase composition, whisker growth and physical properties was investigated. The findings indicated that the spinel saggar exhibited high densities and robust mechanical strength following heat treatment at 800 °C for 3 h, with an apparent porosity of 27.9 %. The cold modulus of rupture (CMOR) and cold crushing strength (CCS) were measured at 5.58 MPa and 21.05 MPa, respectively. The saggar retained rate 75.6 % of their strength after three thermal cycles at 800 °C for 20 min followed by air cooling. Corrosion analysis identified LiAlO 2 as the primary corrosion product of the spinel saggar. PTW facilitated particle bonding, enhancing the strength and toughness of the spinel saggar. This promoted the dispersion and absorption of thermal stresses during cyclic corrosion to prevent further damage. In contrast, for cordierite-mullite saggar corrosion products included LiAlO 2 , eucryptite(β-LiAlSiO 4) and Li 4 SiO 4. The disparate thermal expansion among these phases resulted in the formation of through cracks, exacerbating saggar corrosion damage. The spinel saggar demonstrated superior performance during the cyclic corrosion process. [ABSTRACT FROM AUTHOR]

The thermal expansion coefficient (TEC) mismatch between the cathode and electrolyte presents significant challenge to the thermo-mechanical stability of commercial solid oxide fuel cells (SOFCs). Here a thermal expansion offset composite cathode designated as Ba 0.5 Sr 0.5 FeO 3-δ (BSF)-xNdMnO 3-δ (NM) (x = 0–40 wt%) is developed to address this issue. For the first time, the phase boundary between heterogeneous oxides and the grain size of composite cathode are quantitatively studied with the electron backscatter diffraction (EBSD) technology. For x = 20 wt%, the TEC of cathode decreases by 41 % while the peeling strength of cathode/electrolyte interface increases by 87 %. The highest peak power density (PPD) is achieved for BSF-20NM cathode (1266 mW cm−2 at 650 °C), which is 81 % higher than that for BSF one. Meanwhile, markedly enhanced long-term and thermal cycling stability is obtained. The comprehensive results suggest that both the increased TPB length by enhanced cathode/electrolyte bonding and grain refinement of composite cathode should be responsible for the markedly improved performance and stability. [ABSTRACT FROM AUTHOR]

To develop a high-temperature-resistant adhesive specifically for quartz glass, several groups of aluminum phosphate-based adhesives with different P/Al ratios and Si/B 4 C ratios were prepared, and the bonding performance and mechanism were systematically analyzed. Adding Si and B 4 C affected the decomposition process of phosphates, mainly in terms of the types of decomposition products and the crystal transformation of phosphates. Their addition avoided the generation of metaphosphate and improved the component stability of the adhesive matrix. The oxidation of Si and B 4 C brought about considerable quality compensation, which was crucial for maintaining the structural integrity of the adhesive layer. Besides, the oxidation products further reacted with the adhesive and quartz substrate to form ceramic or glass phases, significantly improving the bonding performance. When the P/Al ratio and Si/B 4 C ratio were 2:3 and 10:3, APSB adhesive presented the best performance. After curing at room temperature or pre-treatment at 1200 °C, the bonding strength reached 16.3 MPa and 14.6 MPa, respectively. After pre-treatment at 1200 °C, APSB could provide above 6 MPa in extreme environments with the range of RT∼1200 °C. The thermal shock resistance of APSB was superior to its thermal cycling resistance. After 10 thermal shocks at 600 °C, 800 °C, and 1000 °C, the bonding strength of APSB is 4.52 MPa, 4.33 MPa, and 7.33 MPa, respectively. Nevertheless, the CTE of APSB adhesive after sintering remained stable at 5.4 × 10−6 K−1, which was still significantly different from the CTE (0.5 × 10−6 K−1) of quartz glass. Therefore, there is great potential for developing low-expansion adhesives in the near future. [ABSTRACT FROM AUTHOR]

When electrophoretic deposition (EPD) is employed for fabricating alumina (Al 2 O 3)-based hydrogen barrier coatings, it becomes customary to enhance the adhesion strength by subjecting the deposited coating to high-temperature annealing. In this study, a functionally-graded Al 2 O 3 /ZrO 2 coating was designed by using the thermal stress module of Ansys software. The influence of different gradient composition distribution indices, number of layers, and layer thickness on the distribution of thermal stress was systematically investigated by simulation. Based on simulation results, the gradient parameters of the functionally-graded coating were determined as follows: a transition layer with three layers, each with a thickness of 0.13 mm; the first layer consisted of Al 2 O 3 to ZrO 2 ratio of 1:3, the second layer with a ratio of 1:1, and the third layer with a ratio of 3:1. Subsequently, the process parameters for EPD of Al 2 O 3 coating were optimized via experimental exploration. Under conditions of deposition time of 120 s, deposition voltage of 60 V, Al 2 O 3 concentration of 8 g L−1 in the electrophoretic solution, and magnesium chloride hexahydrate concentration of 0.6 g L−1, the as-fabricated Al 2 O 3 coating exhibited optimal hydrogen barrier performance. Finally, different proportions of ZrO 2 were sequentially incorporated into the prepared Al 2 O 3 coating to form functionally-graded materials (FGM). Thermal cycling experiments showed that the Al 2 O 3 coating with added ZrO 2 exhibited better stability at high temperatures. Regarding hydrogen barrier performance, the functionally-graded coating outperformed the non-functionally-graded coating. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3), a promising carbon-free energy carrier, can be directly and efficiently converted into electricity in solid oxide fuel cells (SOFCs). However, the NH 3 -fueled SOFC (NH 3 –SOFC) still suffered from several difficulties, including sluggish oxygen reduction reaction (ORR) kinetics and poor cathode durability. In this study, we develop a LSCF-GDC dual-phase cathode with uniform distribution for NH 3 –SOFC. In comparison with commercial counterpart, the dual-phase cathode shows a lower ORR resistance of 0.114 Ω cm2 for at 700 °C due to reduced grain sizes and expanded triple-phase boundary (TPB) length. The resultant NH 3 –SOFC follows the H 2 oxidation process and delivers a comparable peak power density of 0.347 Wcm−2 to H 2 –SOFC at 700 °C, which is further improved to 0.516 Wcm−2 after 280 h activation at 0.7 V. Further operation of five thermal cycles between 700 and 500 °C results in a performance degradation, which can be explained by the microstructure changes of Ni-based anode rather than the dual-phase cathode. Moreover, the thermal cycled NH 3 –SOFC can maintain stable operation without current decay at constant 700 °C and 0.7 V in the subsequent 135 h, further demonstrating the robustness of the dual-phase cathode. Therefore, the introduction of GDC into self-assembled dual-phase cathode is an effective way to synergistically promote the electrochemical activity and durability of the cathode for NH 3 –SOFC. [ABSTRACT FROM AUTHOR]

Recycling high-density micronized (HDM) heat-press glass ceramic ingots to press several restorations would be economical and reduce waste. However, to achieve this, the effects of re-pressing on the optical properties and long-term durability of HDM glass ceramics must be completely understood. The aim of this study was to assess the effects of re-pressing and glazing on the optical properties of HDM heat-press glass ceramic. Twenty-one HDM glass ceramic (Initial LiSi Press) discs were prepared and randomly divided into three groups (n = 7 per group): single heat pressing, double heat pressing, and triple heat pressing. Optical properties, surface roughness, and crystalline structure were measured for each group at three time points: before glazing and thermocycling, after glazing, and after thermocycling. The effect of these independent variables on optical properties were assessed by two-way ANOVA, and Tukey's post hoc test assessed the differences between groups. Heat re-pressing HDM glass ceramic significantly altered its color, reduced translucency, and reduced surface roughness (P < 0.001). After the second heat-press, the color (ΔΕ 00) and translucency parameter changes (ΔTP 00) exceeded perceptible thresholds but not clinically acceptable thresholds, but these were exceeded after the third press for ΔΕ 00. Additionally, glazing lightened the shade of the ceramic, reduced translucency, and reduced surface roughness (P < 0.001), with ΔΕ 00 and ΔTP 00 changes exceeding the perceptible but not the clinically acceptable threshold. Thermocycling produced ΔTP 00 changes that exceeded the clinically acceptable threshold. Further studies of the effects of heat re-pressing on HDM glass ceramic are now needed to progress toward clinical translation. [ABSTRACT FROM AUTHOR]

Evaluation of biaxial flexural strength (BFS) of nanoglass (NG) and multiwalled carbon nanotubes (MWCNTs) reinforced 3D-printed denture base resins and their shear bond strength (SBS) to 3D-printed and acrylic denture teeth. Silanized NG and MWCNTs were added to 3D-printed denture base resin to obtain four groups: Control, 0.25 wt% NG, 0.25 wt% MWCNTs, and a combination group with 0.25 wt% of both fillers. All specimens were tested before and after 600 cycles of thermal aging. BFS (n = 88) was tested using disk-shaped specimens (12 ×2 mm) centralized on an O ring in a universal testing machine. Weibull analysis was conducted to assess predictability of failure. SBS (n = 176) was tested for acrylic and 3D-printed denture teeth attached to bar-shaped specimens in a universal testing machine followed by failure mode analysis using stereomicroscope. Two and three-way ANOVA tests followed by Tukey post hoc test were conducted for BFS and SBS. Kruskal-Wallis test compared percent change among groups with subsequent Dunn post hoc test with Bonferroni correction (α = 0.05). BFS was affected significantly by filler content (P < 0.001) and thermal cycling (P < 0.001), with thermal cycling displaying the uppermost effect (Ƞp2 =0.551). A significant interaction between filler content, thermal cycling, and teeth type was displayed by SBS results (P < 0.001, F=10.340, Ƞp2 =0.162). The highest BFS values belonged to 0.25 % MWCNTs while the highest SBS to printed teeth was displayed by the combination. The combination group displayed higher BFS and SBS to printed teeth compared to control which allows 3D-printed materials to have a long-term clinical success. • The nanofiller addition led to a significant improvement in BFS and SBS. • Thermal cycling had a significant negative effect on the values of BFS and SBS. • The combination and 0.25 % MWCNTs groups revealed better predictability of failure. • The combination group displayed higher BFS and SBS to printed teeth compared to control. [ABSTRACT FROM AUTHOR]

This study investigates failure mechanisms in a typical thermal barrier coating (TBC) system comprising an EB-PVD columnar top coat, an aluminide bond coat, and a Ni-based single crystal superalloy substrate, simulating gas turbine operating conditions using a burner rig. TBC degradation, initiated by interfacial defects from the LASAT method, was studied during thermal gradient cycling under fast and slow cooling. In-situ optical and infrared imaging, along with ex-situ SEM cross-sectional analysis, monitored failure mechanisms. The Laser Shock for Damage Monitoring (LASDAM) technique provided insights into gradient and cooling rate impacts on columnar TBC damage. Results showed significant effects of cooling rate on delamination and localized failure at blister sites, with LASDAM revealing significant overheating at damage sites. Analysis included full-field temperature and damage assessment, emphasizing blister-driven delamination under severe thermal gradients. Discussion focused on elastic stored energy effects, noting that fast cooling induced transient conditions where reversed temperature gradients increased damage, limiting TBC lifespan. • LASDAM demonstrates simplicity and effectiveness for burner rig conditions. • Multiple points within a given specimen are analyzed under different conditions. • Blister formation induces overheating in gradients configuration. • The damage rate is directly influenced by both cooling rate and thermal gradient. • The local maximum temperature is also considered in our study. [ABSTRACT FROM AUTHOR]

Lightweight composites with excellent thermal shock performance exhibit significant potential for thermal structural components. Herein, HfC nanowires modified carbon/carbon (HfC NWs -C/C) composites are fabricated, establishing a three-dimensional network within the matrix. The microstructure of the composites before and after thermal shock cycles were characterized by SEM, XRD and TEM. Additionally, the flexural strength with varied thermal shock were analyzed, which were initially increasing before subsequently decreasing with the number of thermal shock cycles under Ar atmosphere, exhibiting thermal shock strengthening phenomena. While within oxy-acetylene system, the strength of HfC NWs -C/C exhibit an increasement of 75 % compared with C/C after ablation for 6 cycles, which can be attributed to the sintering and the generation of molten film of partial HfO 2 phases that can mitigates oxidation of the matrix, but still lead to a declining trend in the strength following ablative thermal cycles. [ABSTRACT FROM AUTHOR]

The preparation and realization of highly reliable thermal barrier coatings (TBCs) on the internal surface of complex cavities is a bottleneck problem. Traditional coating methods are difficult to deposit and fulfil service requirements. In this study, a novel structure of YSZ and Ce-doped YSZ (CeYSZ) TBCs was prepared by a newly cathode plasma electrolytic deposition (CPED) technology. The results suggested that both the CPED-YSZ and CPED-CeYSZ coatings exhibited porous cross-linked dendritic structures. Because Ce doping significantly improved the phase stability of tetragonal structure and enhanced thermal insulation temperature during a burner-rig test at 1300 °C, resulting in a threefold increase in the thermal cycling life of the CPED-CeYSZ coating compared to the CPED-YSZ coating. This work provided a new strategy for tailoring multiple rare-earth principal components of high-performance TBCs and depositing them on the inner surface of complex cavities with high aspect ratios. [ABSTRACT FROM AUTHOR]

M-YTaO 4 is one of the most promising candidates for the next-generation thermal barrier coatings. However, the CMAS-induced degradation of M-YTaO 4 is still in dispute. This work comprehensively investigates the CMAS corrosion of M-YTaO 4 at 1300 °C which provides new insights into the corrosion mechanism. CMAS attacks M-YTaO 4 forming a thick recession layer and the main corrosion product is accurately confirmed to be (Ca 2-x Y x)(Ta 2-y-z Mg y Al z)O 7 solid solution. The recession layer presented a small difference in Young's modulus with M-YTaO 4. No delamination cracking occurred during the thermal cycling process indicating good reliability. In addition, grain boundary infiltration of CMAS is first revealed in M-YTaO 4. The results have corrected the misjudgment of the corrosion mechanism and CMAS infiltration process in previous studies which provides guidelines for the design of M-YTaO 4 thermal barrier coatings. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings (TBCs) provide thermal protection for high-temperature components of aero-engines and steam turbines, but are susceptible to failure under thermal cyclic loads. The effective design of interfacial texture is one of the approaches to enhance the lifetime of ceramic TBCs. In this study, four types of interfacial textures were designed on the surface of substrates, and 8YSZ coatings of equal thickness were prepared using atmospheric plasma spraying, and thermal cycling tests were carried out. Meanwhile, the thermal cycle lifetime, microstructure evolution, residual stress, and energy release rate criterion were also studied. The optimal morphology and parameters of the texture are determined. It is found that the lifetime of the concave trapezoidal texture is the longest, with a deflection angle of 67°, diameter of 700 μm, depth of 500 μm, and spacing of 5 mm. This study can provide theoretical guidance for the interfacial texture design of ceramic TBCs. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of composition and heating rate on the fast-drying (∼60 min) of red ceramics obtained by extrusion using optical dilatometry and thermogravimetry to obtain the drying curve. Three different plastic clays were used in the four formulations investigated, as well as three heating rates with a total time of 60 min and a maximum drying temperature of 200 °C: 5.83, 3.89, and 2.92 °C/min. Based on the results obtained from the modified Bigot curves, a fast-drying curve (3 °C/min) was established in a static laboratory dryer with a total cycle of 60 min and a maximum temperature of 160 °C. The samples were characterised in terms of compressive resistance and visual aspects related to drying cracks. Formulation F5, containing 50 wt% AM clay and 50 wt% AV clay, exhibited the worst performance in fast-drying with drying cracks, whereas formulation F7, containing 33.3 wt% AC clay, 33.3 wt% AM clay and 33.3 wt% AV clay, exhibited the best performance. Formulations F7 and F8 (16.7 wt% of AC clay, 66.6 wt% of AM clay and 16.7 wt% of AV clay) were fired at 900 °C in an electric kiln, with a heating rate of 1.5 °C/min and a 2 h holding time, and then characterised in terms of firing shrinkage, water absorption and compressive strength. The results showed that Formulation F7 presented suitable behaviour in the fast-drying process at 160 °C for 60 min in a laboratory dryer at a heating rate of 3 °C/min, 0.9 wt% a residual moisture. It exhibited no drying cracks and a dry compressive strength of 0.94 ± 0.09 MPa. However, the combined analysis of optical dilatometry and thermogravimetry indicated that the drying conditions could be optimised for a residual moisture of 2 wt%, using a thermal cycle of 138 °C for 19 min (heating rate of 5.83 °C/min) if adequate control of the humidity of the chamber atmosphere in the first drying stage is employed to avoid drying cracks. The results also showed that the specimens of formulations F7 and F8 met the technological requirements defined by the Brazilian standard ABNT NBR 15270-1, demonstrating the feasibility of producing red ceramic bricks by extrusion with fast-drying. The combined optical dilatometry and thermogravimetry techniques used to obtain the Bigot curve applied to fast-drying showed very good agreement with those obtained in the laboratory dryer. These combined techniques represent promising approaches for studying the fast-drying of red ceramics. [Display omitted] [ABSTRACT FROM AUTHOR]

The formation of cristobalite thermally grown oxides (TGO) is a major life limiting factor for environmental barrier coatings (EBCs) with Si bond coat exposed to high temperature steam environments due to its reversible phase transformation and the resultant cracking behaviour during thermal cycling. Therefore, controlling or avoiding cristobalite TGO formation by engineering coating chemistry and architecture will be desirable for a highly durable EBC system. In this work, a multilayer Si/Al-Si-N/Yb 2 Si 2 O 7 EBC was produced using a hybrid vapor deposition process. The oxidation behavior of the EBC was evaluated in flowing 90% H 2 O (g) + 10% air at 1316 °C. After 100 h and 510 h steam test, crack-free mullite and Al-Si-O-N layers formed above Al-Si-N layer and no SiO 2 scale formation of Si bond coat was observed. Detailed TEM analyses show that the Al-Si-N layer successfully prevented the oxidation of underlying Si bond coat and avoided the formation of detrimental cristobalite phase. [ABSTRACT FROM AUTHOR]

Oxides with the same structure as K 2 NiF 4 have received increasing interest in reversible solid oxide cells (RSOCs) because of the unique advantages of low thermal expansion efficient (TEC), fast oxygen exchange kinetics, and high chemical stability. Herein, Fe-doped Nd 0.8 Sr 1.2 Ni 1-x Fe x O 4±δ (x = 0, 0.15, 0.3, 0.45, NSNF) oxygen electrodes with fast oxygen reduction/evolution reactions (ORR/OER) kinetics are reported. The optimal composition of NSNF is found to be NSNF45 (x equals to 0.45) and the best ratio of NSNF45 to GDC is 6:4 by the mass ratio, delivering a low polarization resistance of 0.067 Ω cm2 at 800 °C. The RSOC with Co-free NSNF45-GDC (6:4) composite oxygen electrode achieves a high peak power density of 1.33 W cm−2 and a favorable electrolysis current density of 1.39 A cm−2 at 1.32 V with 50% steam concentration at 800 °C. Additionally, the reversible cycling between fuel cell and electrolysis modes at 700 °C and the thermal cycling between 700 °C and 300 °C show excellent stability over four hundred hours. The results indicate that composite NSNF45-GDC can be utilized as a promising oxygen electrode material for RSOCs. • A series of Nd 0.8 Sr 1.2 Ni 1-x Fe x O 4±δ are synthesized and evaluated. • The optimal NSNF45-GDC composite shows a R p of 0.067 Ω cm2 at 800 °C. • The cell show good electrochemical performance in both FC and EC modes. • High stability is demonstrated after the reversible cycling and thermal cycling test. [ABSTRACT FROM AUTHOR]

Hydrogen plays a crucial role in global net-zero policies due to its numerous advantages and is widely regarded as a key future fuel. Clean and sustainable hydrogen production technologies are currently a focal point of research, with thermochemical methods showing promise in achieving environmentally friendly hydrogen. This study builds upon previous research conducted by the authors on thermochemical hydrogen production through chlorine family cycles. It conducts a thorough sensitivity analysis of various system variables that significantly impact the overall performance of these processes. The investigation assesses the performance of chlorine family thermochemical cycles from exergetic, exergoeconomic, and exergoenvironmental perspectives. Exergetic performance parameters include net thermal exergies and exergy efficiencies, exergoeconomic parameters encompass hourly levelized and total cost rates, and exergoenvironmental parameters involve exergoenvironmental factors and component-associated environmental impact rates. The system variables under consideration include ambient temperature, system lifetime, annual operating hours, and operation and maintenance cost factor. The analysis reveals that the system's lifetime notably influences both the exergoenvironmental factors and component-associated environmental impact rates (by about 80%). Meanwhile, its impact on both the hourly levelized (around 11.5%) and total cost rates (approximately 1.2%) is comparatively less significant. Similarly, ambient temperature has a marginal effect on the net thermal exergies and exergy efficiencies of the considered cycles. [Display omitted] • A comprehensive sensitivity analysis of chlorine family cycles is presented. • Cycles are studied via exergetic, exergoeconomic & exergoenvironmental perspectives. • Lifetime influences the exergoenvironmental factor by about 80%. • Lifetime influences the hourly levelized cost rate by 11.5% and total cost rate by 1.2%. • Ambient temperature marginally affects net thermal exergies and exergy efficiencies. [ABSTRACT FROM AUTHOR]

To evaluate the hygroscopic expansion characterization of resin composite dies during thermal cycling, and their influence on the fracture resistance of dental ceramic materials as well as the effect of pre-immersion on these measurements. Disc-shaped specimens (φ = 15.0 mm, h = 1.2 mm) and anatomical crown dies of four resin composites (epoxy, Z350, P60, G10) were fabricated. Disc-shaped samples were continuously soaked in distilled water and the volume expansion was measured at different time point by Archimedes method. Disc-shaped samples were pre-immersed for 0, 7, or 30 days, elastic modulus and hardness were measured using Nanoindentation test; thermal cycling (TC) test was performed (5 °C-55 °C, 104 cycles), and volume expansion during TC was measured. Four kinds of resin die with pre-immersion for 0, 7, or 30 days were cemented to 5Y-Z crown, or epoxy dies without pre-immersion were cemented to 5Y-Z, 3Y-Z and lithium disilicate glass (LDG) crowns, and load-to-failure testing was performed before and after TC. Finite element analysis (FEA) and fractography analysis were also conducted. The hygroscopic expansion was in the order: epoxy > Z350 > P60 > G10. Except for G10, the other three resin composites exhibited different degrees of hygroscopic expansion during TC. Only the elastic modulus and hardness of epoxy decreased after water storage. However, only the fracture loads of 5Y-Z and LDG crowns supported by epoxy dies were significantly decreased after TC. FEA showed a stress concentration at the cervical region of the crown after volume expansion of the die, leading to the increase of the peak stress at the crown during loading. Significance : Only the hygroscopic expansion of epoxy dies caused by TC led to the decrease in the fracture resistance of the 5Y-Z and LDG crown, which may be related to the decrease in the elastic modulus of the epoxy die and the tensile stress caused by it. • The hygroscopic expansion of resin dies during thermal cycling decreases the fracture load of their supported ceramic crowns. • The susceptibility of hygroscopic expansion is related to the elastic modulus and the filler/matrix ratio of the resin die. • Pre-immersion of the resin dies could reverse their hygroscopic expansion effect on the supported crown. [ABSTRACT FROM AUTHOR]

To investigate the flexural strength (FS), elastic modulus (E), Martens hardness (HM), water sorption (w sp), water solubility (w sl) and degree of conversion (DC) of 3D-printed, milled and injection molded splint materials. Specimens (N = 1140) were fabricated from five 3D-printed (GR-22 flex, GR-10 guide, ProArt Print Splint clear, V-Print Splint, V-Print Splint comfort), five milled (BioniCut, EldyPlus, ProArt CAD Splint clear, Temp Premium Flexible, Thermeo) and two injection molded (PalaXPress clear, Pro Base Cold) materials. FS, E, HM, w sp , w sl and DC were tested initially (24 h, 37 °C, H 2 O), after water storage (90 d, 37 °C, H 2 O) as well as after thermal cycling (5000 thermal cycles, 5/55 °C). Data were analyzed with Kolmogorov-Smirnov, Kruskal- Wallis, Mann-Whitney U test and Spearman's correlation (p < 0.05). Initially, the mean flexural strength values ranged from 1.9 to 90.7 MPa for printed, 3.8 to 107 MPa for milled and 99.7 to 102 MPa for injection molded materials. The initial mean elastic modulus values were 0.0 to 2.4 GPa for printed, 0.1 to 2.7 GPa for milled and 2.8 GPa for injection molded materials. The initial mean Martens hardness values were 14.5 to 126 N/mm2 for printed, 50.2 to 171 N/mm2 for milled and 143 to 151 N/mm2 for injection molded materials. Initially, the mean water sorption values ranged from 23.1 to 41.2 μg/mm3 for printed, 4.5 to 23.5 μg/mm3 for milled and from 22.5 to 23.3 μg/ mm3 for injection molded materials. The initial mean water solubility values ranged from 2.2 to 7.1 μg/mm3 for printed, 0.0 to 0.5 μg/mm3 for milled and 0.1 to 0.3 μg/mm3 for injection molded materials. After water storage and thermal cycling most of the values decreased and some increased. The mean DC values ranged initially from 72.3 to 94.5 %, after water storage from 74.2 to 96.8 % and after thermal cycling from 75.6 to 95.4 % for the printed materials. The mechanical and physical properties of printed, milled and injection molded materials for occlusal devices vary and are influenced by aging processes. For clinical applications, materials need to be chosen according to the specific indications. [ABSTRACT FROM AUTHOR]

To promote the application of SiC/SiC in hot-end components in aero-engines, the thermal shock behavior of SiC/SiC and SiC/SiC-EBC were investigated in gas combustion environment between 450 °C and 1200 °C. The tensile strength change, microstructure evolution and thermal cycling performance of samples after 200, 400, 1000 and 2000 cycles were studied respectively to reveal the damage and failure mechanism. Cracking damage induced by thermal stress was the main reason for performance degradation of SiC/SiC after initial thermal cycles, then oxidation/corrosion damage dominated with increasing cycles. The oxidation/corrosion damage to SiC/SiC was effectively inhibited by EBC with almost no reduction in strength. However, the poor crack resistance of SiC/SiC was the main factor affecting its thermal shock performance. Improving the crack resistance or self-healing ability of SiC/SiC and combining it with EBC is considered to be an effective strategy to increase its service lifetime. [ABSTRACT FROM AUTHOR]

In this study, the garnet-type Yb 3 Al 5 O 12 coating was fabricated by atmospheric plasma spraying and its properties were systematically investigated. Results show the as-sprayed coating consists of crystalline Yb 3 Al 5 O 12 with amorphous phase, recrystallization occurs at 918.5 °C accompanied by a 0.32% volume shrinkage. Yb 3 Al 5 O 12 coating demonstrates low thermal conductivity (2.1 W/(m∙K) at 1000 °C) coupled with a moderate thermal expansion coefficient (8.87 × 10−6 K−1 from 200 °C to 1400 °C). Additionally, Yb 3 Al 5 O 12 coating displays remarkable structure stability and sintering resistance at elevated temperatures. Its robust corrosion resistance can be demonstrated by rapidly generating dense anorthite layers during CMAS corrosion and the lack of a discernible corrosion layer in water vapor corrosion. Yb 3 Al 5 O 12 /YSZ TBC undertakes a thermal cycling lifetime of 970 cycles, superior to YSZ of 764 cycles. This improvement is primarily ascribed to lower oxygen permeability of garnet layer. These preliminary results indicate that Yb 3 Al 5 O 12 coating might be suitable for advanced TBC applications. [ABSTRACT FROM AUTHOR]

MgO–C refractories are employed as linings for high–temperature containers where they are susceptible to thermal shock and oxidation. In this work, the oxidation behavior of low–carbon MgO–C refractories under thermal cycling was investigated for the first time, and the potential utilization of TiB 2 –BN–AlN (TBA) industrial waste as an additive was also investigated. The results showed that the traditional antioxidant Al was basically ineffective under the condition of thermal cycling; however, the incorporation of TBA industrial waste effectively maintains exceptional oxidation resistance, regardless of thermal cycling. This can be attributed to its capacity to seal the porosity, prevent oxygen intrusion, and absorb elastic strain energy while reducing stress. Additionally, when exposed to an oxidizing atmosphere, MgO–C refractories containing only TBA industrial waste exhibit a low thermal expansion coefficient. [ABSTRACT FROM AUTHOR]

As a promising material for the advanced thermal barrier coatings (TBCs), scandium oxide (Sc 2 O 3) and yttrium oxide (Y 2 O 3) co-stabilized zirconia (ScYSZ) has been given increasing attention during the past decade. In this study, three types of TBCs including YSZ, ScYSZ and ScYSZ-YSZ double ceramic layer (DCL) coatings were deposited by a wide-velocity range high-energy plasma spraying technology. The thermal physical property, phase stability and thermal cycling performance of TBCs were comparatively studied. The results suggested that the thermal conductivity from 200 °C to 1000 °C of ScYSZ coating was reduced by approximately 30 % compared to the YSZ coating. After exposure at 1400 °C for 1000 h, the ScYSZ coating still kept the initial tetragonal phase structure, while the tetragonal phase was completely disappeared in the YSZ coating after 300 h at 1400 °C. Notably, the ScYSZ-YSZ DCL coating demonstrated the highest thermal cycling life within the temperature range of 1320∼1370 °C, exhibiting a remarkable 43 % increase over the single ScYSZ coating and doubling that of the single YSZ coating. The outcomes of this study hold significant promise for practical applications in the realm of high-performance TBCs. [ABSTRACT FROM AUTHOR]

Since its inception in the 1980s, advancements in PCR technology using improved thermal cyclers, engineered DNA polymerases and commercial master mixes, have led to increased PCR productivity. Despite these advancements, PCR cycling protocols have largely remained unchanged over the same period. This study aimed to systemically evaluate the effect of reduced PCR cycling parameters on amplicon production. The 1466bp fragment from the 16S rRNA gene present in low-, medium- and high-CG bacteria was amplified using three commercially available PCR master mixes. The shortest cycling parameters required to successfully amplify the 16S fragment from all bacteria and master mixes comprised 30-cycles of 5 s denaturation, 25 s annealing, and 25 s extension. While all produced an amplicon with sufficient yield to enable downstream sequence analysis, the PCRBIO Ultra Mix in conjunction with the shortened parameters was found to achieve the highest amplicon yield across low-, medium- and high CG bacteria. Comparing the run times to that of a typical 16S PCR protocol, the shortened cycling parameters reduced the program duration by 46 % and consumed 50 % less electricity, translating into increased productivity and helping to improve laboratory environmental sustainability. • Quicker and more environmentally sustainable PCR. • The 16S PCR program duration reduced by 46 % compared to typically published protocols. • The 16S PCR program consumes 50 % less electricity. • Amplicon produced from low-, mid-, and high-GC bacterial templates. [ABSTRACT FROM AUTHOR]

YbTaO 4 -Ta 2 O 5 composites were designed and different multi-layered YbTaO 4 -Ta 2 O 5 /Yb 2 Si 2 O 7 /Si (YbT-T/YbDS/Si) as well as YbTaO 4 -Ta 2 O 5 /Si (YbT-T/Si) environmental barrier coatings (EBCs) were put forward to protect SiC fiber reinforced silicon carbide (SiC f /SiC) ceramic matrix composites (CMCs). The thermal cycling and the water-vapor/oxygen corrosion behavior of different multi-layered EBCs were compared. Results indicated that the thermal cycling lifetime of the bi-layered YbT-T/Si EBCs was similar with the tri-layered YbT-T/YbDS/Si ones. The ultimate failure of these two EBCs was induced by the cracking of the SiC f /SiC substrates as well as the vertical cracks associated with the thermal mismatch stress among different layers. However, the tri-layered EBCs exhibited greater resistance to water-vapor/oxygen corrosion than the bi-layered ones, primarily due to that the tri-layered YbT-T/YbDS/Si EBCs contained significantly less cracks than the bi-layered ones, limiting the transport of reactant (oxygen and/or water vapor) to reach Si bond coat. [ABSTRACT FROM AUTHOR]

Recently, high-temperature composites reinforced with in-situ phases have been developed as a new class of composites for harsh environments. The behaviour of these composites under sudden heating and cooling conditions is greatly influenced by the type and fraction of components. The aim of this study is to investigate the microstructural properties and mechanical response of iron based composites after thermal shock cycling. The fabrication process involved in-situ powder metallurgy (IPM) sintering of Fe–B 4 C starting powders. The samples were subjected to thermal shock with a constant temperature differences (ΔT: 600 °C) and varied cycles (N: 1–50). Comparison of microstructural changes and mechanical behaviour before and after thermal shock has been carried out. The boron atoms released from the initial B 4 C generated diffusion zones in the matrix dominated by iron boride phases (Fe 2 B/FeB). An effective matrix-reinforcement interface has been created by in-situ powder metallurgy, where boride phases are almost homogeneously distributed in the iron matrix. While the hardness of the composites was significantly developed by the Fe 2 B/FeB phases, the addition of B 4 C resulted in a reduction in the coefficient of thermal expansion (CTE). The in-situ phases contributed in the minimisation of the coefficient mismatch by balancing the thermal expansion coefficients between iron and the initial B 4 C. Under the influence of thermal shock, microcracks and then macrocracks formed on the sample surfaces, increasing in width and depth with thermal cycles. This resulted in accelerated fracture damage under post-thermal loading. Both the impact and flexural strengths of the samples were significantly reduced as the number of thermal cycles increased. Although the 20% B 4 C reinforced composite provided maximum hardness, it showed poor resistance to thermal loading. The best results for mechanical loads were achieved by the 5% B 4 C reinforced composite, which showed no cracks even after 50 thermal cycling. [ABSTRACT FROM AUTHOR]

In this work, the Y 3 Al 5 O 12 (YAG) coatings prepared by atmospheric plasma spraying were found to have a thermal expansion coefficient of 8.51 × 10-6K-1 from 473 to 1673K and a thermal conductivity of 2.41 W/(m∙K) at 1273K as well as a Young's modulus of 89.4 ± 9 GPa and an average hardness of 6.79 ± 0.24 GPa. Their excellent mechanical and thermal-physical properties have promoted them as thermal/environmental barrier coating (T/EBC) materials. Multi-layered Y 3 Al 5 O 12 /Yb 2 SiO 5 /Yb 2 Si 2 O 7 (YAG/YbMS/YbDS) T/EBCs were deposited on SiC based substrate. Thermal cycling and water vapor corrosion behavior of the YAG/YbMS/YbDS T/EBCs were also investigated. The cyclic oxidation tests at 1573K showed that the coatings had excellent resistance to thermal cycling, with an average lifetime of 442 ± 10 cycles. The initial oxidation of the Si layer at the edge, resulting in the formation of a 4.8 μm thick thermally grown oxide (TGO), coupled with the volumetric changes and the associated phase transformation stress, led to the delamination of the coatings from the edges. Due to the very low oxygen diffusion rate of YAG layer, the thickness of TGO was only 1.2 μm after steam corrosion for 40 h. The amorphous crystallization as well as thermal mismatch stresses were the main reasons for the coating failure. [ABSTRACT FROM AUTHOR]

The zirconia-based thermal barrier coating co-doped with trivalent and pentavalent oxides was deposited on DD 90 single crystal superalloy using air plasma spraying. The coating is composed of cubic and tetragonal phases denoted by bi-phase solid solution (BPS) ceramic coating. The microstructure, cross-sectional morphology, and cracks evolution of BPS coatings, before and after 1200 °C thermal cycling, were investigated compared with 8YSZ coating. The BPS coating is intact after 250 thermal cycles, and the phase constitution is consistent with as-sprayed state. On the contrary, the brittle monoclinic phase can be observed in the thermal cycled 8YSZ coating, and severe exfoliation occurred. The propagation and splitting of the cracks are inhibited by the randomly distributed nanocrystalline clusters, and the cracks are inclined to grow longitudinally, which are beneficial to improve the toughness and thermal shock resistance of thermal barrier coating. [ABSTRACT FROM AUTHOR]

The current dental resin composites often suffer from polymerization shrinkage, which can lead to microleakage and potentially result in recurring tooth decay. This study presents the synthesis of a novel monomer, (3,9-diethyl-1,5,7,11-tetraoxaspiro[5,5]undecane-3,9-diyl)bis(methylene) bis((2-(3-(prop-1-en-2-yl)phenyl)propan-2-yl)carbamate) (DDTU-IDI), and evaluates its effect in the formulation of low-shrinkage dental resin composites. DDTU-IDI was synthesized through a two-step reaction route, with the initial synthesis of the required raw material monomer 3,9-diethyl-3,9-dihydroxymethyl-1,5,7,11-tetraoxaspiro-[5,5] undecane (DDTU). The structures were confirmed using Fourier-transform infrared (FT-IR) spectroscopy and hydrogen nuclear magnetic resonance (1HNMR) spectroscopy. Subsequently, DDTU-IDI was incorporated into Bis-GMA-based composites at varying weight percentages (5, 10, 15, and 20 wt%). The polymerization reaction, degree of conversion, polymerization shrinkage, mechanical properties, physicochemical properties and biocompatibility of the low-shrinkage composites were thoroughly evaluated. Furthermore, the mechanical properties were assessed after a thermal cycling test with 10,000 cycles to determine the stability. The addition of DDTU-IDI at 10, 15, and 20 wt% significantly reduced the polymerization volumetric shrinkage of the experimental resin composites, without compromising the degree of conversion, mechanical and physicochemical properties. Remarkably, at a monomer content of 20 wt%, the polymerization shrinkage was reduced to 1.83 ± 0.53%. Composites containing 10, 15, and 20 wt% DDTU-IDI exhibited lower water sorption and higher contact angle. Following thermal cycling, the composites exhibited no significant decrease in mechanical properties, except for the flexural properties. Significance. DDTU-IDI has favorable potential as a component which could produce volume expansion and increase rigidity in the development of low-shrinkage dental resin composites. The development of low-shrinkage composites containing DDTU-IDI appears to be a promising strategy for reducing polymerization shrinkage, thereby potentially enhancing the longevity of dental restorations. • A new monomer "DDTU-IDI" was synthesized through a simple two-step reaction route. • The composites containing 10 wt% ∼ 20 wt% DDTU-IDI exhibited low polymerization shrinkage. • The addition of DDTU-IDI effectively maintained the mechanical properties of the composites. • The composites containing DDTU-IDI showed favorable resistance to aging. • The novel composites may be a promising dental restoration material in reducing the occurrence of secondary caries. [ABSTRACT FROM AUTHOR]

In present study, thermal energy storage microcapsules with double-layer ceramic shell were fabricated and thermal cycling test was conducted. Thermal cycling test results showed that when ceramic shell constituted of dense inner layer and loose outer layer, the microcapsule had excellent thermal stability. After 3000 thermal cycles, latent heat retention ratio of the microcapsule was more than 90 % and almost no leakage of molten core. This super durability and stability attributed to "sponge effect" of loose outer layer which offered volume buffer for microcapsule core and inhibited molten core overflow during phase change. According to the Mass Conservation Law, criterion Г for describing "sponge effect" was deduced. Г was defined as a quarter of the product of the specific surface area of the microcapsule and criterion Г was derived as Г ≥ 1 ρ L − 1 ρ S . The criterion shows that when the value of Г is larger than or equal to the difference between the specific volumes of liquid and solid phase change material, microcapsule core is not overflow during phase change. Criterion Г provides theoretical guidance for the preparation of thermal energy storage microcapsules with excellent thermal cycling performance. [ABSTRACT FROM AUTHOR]

Mechanical alloying and spark plasma sintering were used to prepare dense SiC w /SiAlCN ceramics. The effects of whisker content on the mechanical properties and oxidation resistance were investigated. Compared with SiAlCN ceramic, the fracture toughness of 5 wt% SiC w /SiAlCN ceramic increased by 31.8 % to 5.8 MPa m1/2, which was attributed to crack deflection/branch and SiC w bridging/pull-out. Based on quantitative calculation, SiC w bridging/pull-out increased fracture toughness by 27.8 %. The flexural strength of 5 wt% SiC w /SiAlCN ceramic was 523.2 MPa, which was 26.9 % higher than that of SiAlCN ceramic. The residual strengths of the SiC w /SiAlCN ceramic after 50 h isothermal oxidation at 1500 °C and 50 times thermal cycles from room temperature to 1500 °C were 292.5 and 449.7 MPa. Because of SiAlCN matrix passive oxidation and SiC w active oxidation, a double-layer oxide scale composed of glassy scale and porous scale was formed on SiC w /SiAlCN ceramics. The unoxidized whiskers could remain original morphology and were available to strengthening and toughening. [ABSTRACT FROM AUTHOR]

Symmetric-structure metal-supported solid oxide fuel cells and electrolysis cells (MS-SOFCs, MS-SOECs) offer several advantages over conventional solid oxide cells, including the use of inexpensive materials, high mechanical strength, and rapid ramp-up ability. Aggressive operation of MS-SOCs in fuel cell mode is well-established, including extremely fast start-up, redox tolerance, and imbalanced pressure. Here, we extend dynamic operation to MS-SOCs in SOEC mode with high steam content for both small button cells and a large rectangular cell, including: steam cycling, thermal cycling, redox cycling and power cycling. Steam cycling entailed switching between 3:97 and 50:50 steam:hydrogen ratio. For thermal cycling, the temperature was rapidly varied between 150 °C and 700 °C for 50 cycles. Redox cycling involved switching the steam side gas between 50 % humidified H 2 and 50 % humidified N 2 for 5 cycles. Power cycling was performed by operating the cell under variable current density, resulting in cell voltage between 1.3 V and 2.8 V. Degradation rates for each testing strategy were compared to a baseline cell, and found to be similar. The excellent tolerance to dynamic operation increases confidence that MS-SOECs will be compatible with dynamic or intermittent renewable resources. • MS-SOEC show significant stability under variable steam content during steam cycling. • Small and large MS-SOECs exhibit excellent tolerance to rapid thermal cycling. • MS-SOECs display minimal degradation during redox cycling. • The cells show remarkable adaptability to power cycling. • Scaling up to a larger cell maintains similar performance and stability. [ABSTRACT FROM AUTHOR]

In order to improve cost competitiveness and the further application of metal-supported cells, it is important to explore cathodes suitable for low-temperature sintering. However, decreasing cathode sintering temperature while maintaining robust interface of cathode/electrolyte and decent electrochemical performances is challenging for solid oxide fuel cells. Herein, by combining the Pechini method with one-pot method, La 0.6 Sr 0.4 CoO 3-δ @ Gd 0.1 Ce 0.9 O 2-δ (LSC@GDC) composite cathodes are prepared and investigated, compared with mechanically mixed LSC-GDC cathodes. At the cathode sintering temperature of 800 °C, the LSC@GDC cathode single cells perform better performances, with deceased resistances, improved power density outputs and better feasibility to wide oxygen partial pressures from 0.21 atm down to 0.03 atm. The optimum composition of 70:30 wt% for LSC@GDC is proposed. The anode supported single cell with LSC@GDC30 cathode exhibits a maximum power density of 0.789 W/cm2 and 0.545 W/cm2 at 750 °C, under cathode oxygen partial pressure of 0.21 atm and 0.03 atm, respectively. Moreover, the low temperature sintered LSC@GDC50 cathode performs decent durability during repeatedly controlled thermal cycling over 10 times. • LSC@GDC cathode is successfully prepared by novel two-step one-pot method. • The cathode sintering activity improves as well as interface contact. • The cell performance in harsh condition is dramatically enhanced. • The cell exhibit decent long-term durability and thermal cycling stability. [ABSTRACT FROM AUTHOR]

SiO/C is currently considered the most favorable anode material for high-energy-density lithium-ion batteries (LIBs). Nevertheless, its potential applications are constrained because of its inherent capacity decay and thermal safety concerns engendered by its volumetric expansion during extended cycling periods. The present study investigated the effectiveness of 4,5-difluoro-1,3-dioxolane-2-one (DFEC) as a film-forming additive to augment the safety and electrochemical efficacy of LIBs. A blank electrolyte (BE) was used as a control. Electrochemical test and characterization results revealed that the capacity retention rate of a battery containing the DFEC additive improved significantly; specifically, it increased from 45.23% (for a battery with the BE) to 73.14%. DFEC also increased the quantity of LiF components on the anode surface, resulting in the formation of a robust and stable solid electrolyte interphase film, which enhanced the battery's cycling stability. Differential scanning calorimetry, thermogravimetric analysis, and thermokinetic analysis revealed that DFEC inhibited exothermic reactions between the electrolyte and the lithiated anode. Notably, the initial reaction temperature for the electrolyte slowly transitioned from 232.17 to 238.67 °C. The apparent activation energy increased from 439.56 to 506.995 kJ/mol. This study presents a practical approach for the development of safe, high-energy-density batteries by incorporating DFEC as a film-forming additive. [ABSTRACT FROM AUTHOR]

Stacking of solid oxide cells (SOC) requires that a robust and durable electrical contact is established between the cell and the interconnect. In this work, we present a contact layer solution for the SOC air side based on the concept of reactive oxidative bonding in which metallic Mn-Co and Mn-Cu particles are oxidized in-situ during stack initiation or operation to form robust well-conductive spinel oxides. The long-term (3000 h) stability of the new contact layers is evaluated by measuring the area specific resistance (ASR) during aging in air at 750 °C and 850 °C, and during thermal cycling. Both Mn-Co and Mn-Cu layers are found to be well compatible with a CeCo coated 441 steel interconnect material, and do not significantly contribute to the resistance across the stack element. The resistance is dominated by the coated steel. [ABSTRACT FROM AUTHOR]

The hydrogen isotopes are vital due to their significant applications in scientific research, biomedicine and potential application in fusion energy. D-T fusion, in particular, holds the promise solving human fossil energy reliance and the resulting environmental pollution. Methods including cryogenic distillation and Girdler Sulfide process etc. have been developed to satisfy the demand towards pure D 2 and T 2 but generally suffer high energy consumption and low separation efficiency. Furthermore, emerging methods such as laser catalysis and quantum sieving have been demonstrated but suffers harsh separation conditions, low separation volumes and material life etc. Thermal cycling absorption process (TCAP) delivers seductive aspects regarding hydrogen isotope separation for efficiency and throughput, small footprint and high automation level. Herein, firstly, the advantages and disadvantages of various separation methods are briefly elucidated and provides the necessities for developing new separation methods. Then the preferred TCAP strategy is outlined in detail, containing working mechanisms and optimization process. Finally, the history and outlook of TCAP are listed. We hope this paper would spark some inspirations for further TCAP development towards hydrogen isotope separation. [Display omitted] • The necessity of hydrogen isotope separation was explained. • The pros and cons of the current separation methods were summarized. • The principles, working modes, and optimization of TCAP were summarized. • The future prospects of TCAP were proposed. [ABSTRACT FROM AUTHOR]

This paper carried out a high-temperature thermal gradient cycling test of ceramic matrix composites (CMCs), investigating the failure characteristics of CMCs in non-uniform high-temperature environments. The result shows that the damage characteristics of CMCs under thermal gradient environments are significantly different from those under uniform temperature environments. The SiC fiber pull-out lengths at different yarn fractures have obvious differences in the thermal gradient direction. The thermal stress damage propagation pattern of CMCs under the thermal gradient environment is revealed by numerical analysis, and its residual mechanical properties under different thermal gradient environments are predicted. The numerical results could be adopted as a theoretical basis and suggestions for temperature control of CMCs components in practical applications. [ABSTRACT FROM AUTHOR]

Corrosion of calcium magnesium aluminum silicate (CMAS) severely affects the durability of thermal barrier coatings (TBCs). In this study, 8 wt% Y 2 O 3 partially stabilized ZrO 2 (8YSZ) coatings were prepared using atmospheric plasma spraying (APS) technique, and a Pt–Al film was magnetron-sputtered onto the surface of the YSZ coating (Pt–Al-YSZ) to enhance its resistance against CMAS. The results indicated that the Pt–Al-YSZ coating displayed superior non-wetting performance against CMAS, as well as stronger resistance to CMAS corrosion. The results evidenced by Raman spectra and X-ray diffraction showed that phase transformation was smaller and corrosion depth was lower after CMAS corrosion at 1250 °C for 2 h. The thermal cycling test was also performed. The result demonstrated that the Pt–Al coating did not have a negative impact on the thermal cycling life of the YSZ TBCs. However, platinum tended to soften at high temperatures and became easily penetrated by molten CMAS. Therefore, it is necessary to further improve the strength of platinum layer to fully utilize its protective effect against CMAS attack. [ABSTRACT FROM AUTHOR]

The separation of hydrogen isotopes is a vital step in preparing tritium and deuterium fuels for future fusion power plants. This represents a fundamental challenge to fusion energy since the separation process must be able to handle high throughputs of hydrogen isotopes whilst maintaining a low tritium inventory, because tritium is highly radioactive. There are many possible isotope separation techniques, however none that are currently deployable can meet the demands required. To address this gap, recent developments have improved existing processes and created new high-performance processes including Thermal Cycling Absorption Process (TCAP), electrochemical graphene sieving and absorbative separation based on quantum sieving. In this article, ten of the most promising future hydrogen isotope separation technologies are reviewed, to understand the development route to a process that addresses this key challenge of fusion energy. [Display omitted] • Comprehensive review of new and established isotope separation technology. • Cryogenic distillation, TCAP, PSA, membrane, gas chromatography. • Plasma chemical, thermal diffusion, and laser isotope separation. • Tritium inventory, separation factor and scalability are considered. • Effect of quantum sieving in porous solids and palladium absorption. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the immediate dentin bond performance and bond durability of self-adhesive resin luting cements (RLCs) in combination with universal adhesives in different curing modes. Two self-adhesive RLCs were used with universal adhesives as primers. They were also used alone as self-adhesive RLCs. Two multiple-step RLC systems were used as comparison materials. To measure the shear bond strength (SBS) in different curing modes, 12 specimens were prepared for each group. Stainless-steel rods were bonded to bovine dentin, and the bonded specimens were assigned to the baseline group (stored for 24 h) and artificially aged group (thermal cycling [TC], 10,000 cycles). After each storage period, the SBS of the bonded specimens was measured. The Knoop hardness number (KHN) of the cured RLCs was measured with or without primer application in different curing modes at 24 h and after 10,000 TC. The representative RLC/dentin interfaces were observed using scanning electron microscopy (SEM). Dentin SBS was significantly influenced by the RLC system but not by the curing mode. Self-adhesive RLCs alone showed significantly lower SBS values than self-adhesive RLCs with primer regardless of the curing mode or storage period. The storage period, curing mode, and RLC system significantly influenced the KHN. The use of universal adhesives as a primer may help enhance the immediate dentin bond performance and bond durability of self-adhesive RLCs. [ABSTRACT FROM AUTHOR]

In response to the problem of high-temperature oxidation and volatilization of SiC coatings on carbon materials at 1700 ℃, this paper proposes to prepare ZrB 2 -LaB 6 modified SiC coatings on graphite substrate surface by spark plasma sintering. The oxidation protection performance of five different ZrB 2 -LaB 6 -SiC coatings with different ratios of ZrB 2 and LaB 6 was tested at 1700 ℃ isothermal environment and thermal shock environment. The results showed that the oxidation protection efficiency of the coated samples with LaB 6 content of 0, 3, 5, 8 and 10 wt% after oxidation for 100 min at 1700 ℃ was 96.6%, 98.0%, 96.9%, 96.4% and 95.5%, respectively. The coating with 3 wt% LaB 6 had the best oxidation protection effect with the coating still maintaining its integrity and high oxidation protection efficiency after 20 thermal shock cycles with an overall oxidation protection efficiency after thermal cycling of 97.7%. [ABSTRACT FROM AUTHOR]

Li 2 TiO 3 (lithium titanate) is a material of interest in the field of fusion reactors due to its potential application as a tritium breeder material. Because of the extreme working conditions and temperature gradients involved, thermal expansion properties are critical to consider when assessing a material for a fusion reactor. The reactor is subjected to severe neutron flux, high temperature and thermal cycling, which can cause significant stress on the material. A low coefficient of thermal expansion (CTE) of Li 2 TiO 3 is important as it mitigates mechanical stress and minimized the risk of structural damage resulting from thermal cycling. Material degradation, cracking, or delamination might result from a mismatch in CTE between different materials in the reactor. Therefore the estimations of material's thermal expansion properties hold significance for the designing and fabrication of structural material. In this study, Li 2 TiO 3 material was compacted into pellets and high-temperature X-ray diffraction (HT-XRD) was employed to obtain X-ray diffraction patterns from room temperature to 1273 K at 100 K intervals. The lattice parameters (a, b, and c) of Li 2 TiO 3 polycrystals were determined and corresponding unit cell volumes were estimated at each temperature. The thermal expansion percentages for the lattice parameters a, b, and c between room temperature and 1273 K were found to be 1.21%, 1.84%, and 1.83% respectively. The calculated coefficient of thermal expansion (CTE) were determined as 12.5 × 10−6 K−1, 19 × 10−6 K−1, and 18.9 × 10−6 K−1for lattice parameters a, b and c respectively. The crystallographic density at room temperature was estimated to be 3.42 g/cm3. The molar volume was calculated to range between 32.12 and 33.72 cm3/mol from room temperature to 1273 K. Additionally, high-temperature dilatometry was employed to measure the thermal expansion of Li 2 TiO 3 , resulting in the estimation of coefficient of thermal expansion. From room temperature to 1290 K, the thermal expansion percentage and mean coefficient of thermal expansion were calculated to be 1.91% and 19.64 × 10−6 1/K, respectively. Furthermore, the temperature dependent mean and instantaneous thermal expansion values were also determined. The differential scanning calorimetry (DSC) method was used to estimate the temperature of the monoclinic to cubic transformation, which was determined to be 1416 K. This paper provides a comprehensive description of the conducted experiments, accompanied by the detailed analysis of the thermal expansion properties derived through the use of High-Temperature X-Ray Diffraction (HT-XRD) and HT-dilatometry (High-Temperature Dilatometry). [ABSTRACT FROM AUTHOR]

Heat charging and discharging performances and cycling stability of the coupled MgH 2 –LaNi 5 thermal storage system are investigated. Heat storage reaction is studied by tracking temperatures and pressures of hydride beds as well as hydrogen mass flow rates exchanging between MgH 2 and LaNi 5. Upon 20 heat storage cycles, MgH 2 –LaNi 5 pair reveals remarkably cycling stability with the energy densities during heat charging and discharging of 797 ± 37.5 and 680 ± 28 kJ/kg, respectively. The hydrogen content exchange between MgH 2 and LaNi 5 during heat storage cycles is up to 57 % of theoretical hydrogen capacity. The possibilities to enhance the hydrogen contents participating in the heat storage reaction are discussed. The heat charging and discharging performances at different positions in the hydride beds of MgH 2 –LaNi 5 pair are characterized. Not only thermodynamic compatibility of MgH 2 and LaNi 5 but also kinetics as well as hydrogen and heat transfer in MgH 2 beds considerably influence heat storage performance. • Heat dis/charging stability upon 20 cycles of MgH 2 –LaNi 5 pair is confirmed. • H 2 exchange reactions between MgH 2 and LaNi 5 upon heat storage cycles are studied. • T and ESD during heat discharging are up to 310 °C and 680 ± 28 kJ/kg, respectively. • Up to 57 % of theoretical H 2 capacity of MgH 2 participates in heat storage cycles. • Heat storage of MgH 2 depends on kinetics, H 2 diffusion, and thermal conductivity. [ABSTRACT FROM AUTHOR]

The study aims to investigate the influence of infrared emissivity on thermal barrier coating (TBCs) for service applications. Two double-layer TBCs, namely RMgAl 11 O 19 /YSZ (marked as RMA/YSZ, R=La, Pr) and conventional single-layer YSZ TBCs, were comparatively tested using a burner rig facility. The microstructure, infrared emissivity, and thermal cycling performance of the three TBCs were investigated. The results demonstrate that the emissivity of PrMA/YSZ has been improved by approximately 20% compared to LaMA/YSZ in the wavelength range of 2–6 µm, owing to an improvement in electronic transition. Due to higher emissivity, the surface temperature of PrMA/YSZ decreased by 70 °C under the same heat flux, leading to a reduction in coating aging and substrate temperature. Accordingly, PrMA/YSZ exhibited the highest thermal cycling lifetime among the three coatings. [ABSTRACT FROM AUTHOR]

Polyetheretherketone (PEEK) is a highly sought-after thermoplastic due to its exceptional mechanical properties and biocompatibility. However, bonding PEEK to indirect composite resin (ICR) or denture-based resin (DBR) can be challenging. Laser engraving technology has shown potential to improve bonding for other materials; thus, this study aims to evaluate its effectiveness for PEEK. The experiment involved preparing ingot-shaped PEEK samples, which were then categorized into four groups based on the treatment method employed: without treatment, air abrasion, sulfuric acid etching, and laser engraving (LS). Subsequently, the samples were bonded to ICR or DBR, and their shear bond strength (SBS) was tested with or without thermocycling using a universal testing machine. Furthermore, the failure mode was observed, with statistical analyses conducted to compare the results. The grid-like microslit structure of LS group displayed the highest SBS for bonding PEEK to ICR or DBR (P < 0.05). During the bonding of PEEK to ICR, resin residue and penetration into the microslits were frequently observed in the LS group, indicating cohesive failure. However, when PEEK was bonded to DBR, mixture failure was frequently observed without thermocycling. After thermocycling, only the LS group showed cohesive failure, while the majority of specimens exhibited mixture failure. Laser engraving significantly improves the SBS between PEEK and both ICR and DBR. Furthermore, it was observed that resin had penetrated the microslits, indicating that laser engraving has great potential as a surface treatment method. [ABSTRACT FROM AUTHOR]

At present, due to the existent trap levels, the investigation of the dual-fluorescence emission with temperature-dependency of Eu2+ and Eu3+ in long afterglow materials needs to be supplemented. In this work, Eu2+ and Eu3+ co-doped borate glass materials containing Ca/SrAl 2 O 4 crystals are successfully prepared though solid phase melting method, presenting a temperature-dependent fluorescence emission changing from blue-violet to red-orange between 300 and 500K. This interesting finding is proved to be the different thermal quenching behavior caused by the varied luminescence transition mode of Eu2+ (440 nm) and Eu3+ (614 nm). Further, the instantaneous and the delayed trap carriers release is demonstrated to moderate the thermal quenching behavior, leading to better sensing performance at high temperatures in sample of more trap distribution, with S r (max) being 1.3535% K−1 at 483K. Finally, good thermal cycling reversibility of the material shows that the temperature-dependent luminescence of Eu2+/Eu3+ assisted by traps is potential for optimizing the application of temperature sensing. [ABSTRACT FROM AUTHOR]

Sintering-induced healing of intrinsic micropores is the main cause of thermal insulation degradation in plasma-sprayed thermal barrier coatings (TBCs). Although large pores can effectively retain the thermal-insulation performance, they can lower the mechanical performance during thermal cyclic tests. Therefore, balancing the tradeoff between the thermal and mechanical performances is a challenging task. Herein, sintering-resistant coatings were achieved through a matching design that co-enhances the thermal insulation and thermal cycling span. TBCs with different contents of sintering-resistant pores were prepared. The thermal-insulation performance was found to be positively correlated with the contents of sintering-resistant pores. However, in thermal cyclic tests, the lifespan increased as the pore content increased from 0 vol% to 20 vol% but drastically decreased as the pore content increased further above 20 vol%. Next, the competing effects of the newly formed pores on the crack driving force and fracture toughness, which might hasten TBC failure, are discussed. Based on the critical pore content, the matching design enhances the thermal insulation and lifespan of the resultant TBCs by 50% and 40%, respectively, from those of conventional TBCs. Therefore, the sintering-resistant structure is expected to considerably contribute to next-generation applications of TBCs. [Display omitted] [ABSTRACT FROM AUTHOR]

Li 2 TiO 3 ceramic pebbles with uniform structure, high density and good mechanical property were successfully fabricated by wet process. The Li 2 TiO 3 pebbles sintered at 1000 °C for 4 h had satisfactory density (91% T.D.) and crush load (a.v. 27.1 N). The apparent activation energy of Li 2 TiO 3 grain growth was 201 ± 7 kJ/mol. Accelerated densification was observed in a reducing atmosphere, this might be attributed to the oxygen vacancies generated by the reduction of Ti4+ to Ti3+ in 0.1%H 2 +He atmosphere, which facilitate the diffusion of ions through the lattice. The grain growth was controlled by lattice diffusion under reducing atmosphere, and the apparent activation energy was 168 ± 6 kJ/mol. The mechanical results show that the crush load of Li 2 TiO 3 pebbles decreased with the increase of temperature, and the average crush load at 500 °C was 13.9 N. In addition, the thermal cycling and long-time annealing experiments suggested that Li 2 TiO 3 pebbles have good structural and performance stability. The Li 2 TiO 3 ceramics prepared by wet process were satisfactory tritium breeder materials with ideal application potential. [ABSTRACT FROM AUTHOR]