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• A novel thermal fatigue test method of pistons is proposed. • Different thermal expansion coefficient between Al and Si is the main reason of micro-crack initiation. • The life prediction error of tensile strain energy density method is less than 10 %. This study proposed a new test method to take the piston instead of the internal combustion engine as the experimental object and use electromagnetic induction heating and auxiliary cooling to simulate the actual operating conditions of the piston during engine start-stop, to achieve accurate control of the temperature of the heating and cooling cycles. The experimental process can be accelerated by worsening the service conditions. In order to prove the feasibility of this scheme, the temperature field distribution, fatigue life, and failure mode of the piston are compared and analyzed using finite element simulation, theoretical calculation, and surface topography observation. The results show that the error between the simulated temperature value of the key point of the piston and the experimental value of the actual operating condition is less than 5%, the position and value of the maximum temperature of the piston under the thermal fatigue test condition are consistent with the actual engine operating condition, the error between the fatigue life test results and the theoretical calculation results is less than 10%, and the location and cracking mode of the main crack is consistent with the actual working condition. It is proved that the test method is reasonable and feasible, which can provide an important guarantee for the fast and efficient design of high-performance pistons. [ABSTRACT FROM AUTHOR]

Nighttime driving safety is a key focus in transportation research due to accidents caused by drivers' inability to clearly see road obstacles, leading to delayed or incorrect decisions. To address this, the use of mechanoluminescent materials on surfaces like roads and buildings offers a potential solution for better object contour detection in poor visibility. This study investigates the use of SrAl 2 O 4 as a phosphor matrix, exploring its luminescence characteristics and the effects of doping with Eu2+ and Dy3+. The optimal doping ratios were determined to be 2 % Eu and 1 % Dy by trap modulation, producing phosphors with significant mechanical luminescence and a prolonged afterglow. Spectroscopic analysis and image assessment demonstrated a visible afterglow lasting up to 60 min, along with impressive mechanical luminescence performance. By combining the developed SrAl 2 O 4 :Eu2+, Dy3+ phosphor-based coating with polydimethylsiloxane, a real-time surface stress sensing system was devised utilizing digital camera and other optical sensors. This advancement facilitates the visualization of stresses in complex or confined environments, potentially improving nighttime driving safety through enhanced object contour detection. [ABSTRACT FROM AUTHOR]

All human beings contribute to climate change; however, their contributions are not equal. Using China as an example, the core objective of this study is to explore the city-level carbon inequality of residential buildings from 2015 to 2020 combined Theil index and Gini coefficient. The outcomes indicate that: (1) Total residential buildings' carbon emissions in 321 Chinese cities increased from 987.81 million tons (Mt) in 2015 to 1161.70 Mt. in 2020; the leading five cities that own the largest carbon emissions are Beijing, Tianjin, Shanghai, Shenyang, and Harbin in 2020. (2) Among eight major economic zones of China, the highest residential buildings' carbon emission per capita and residents' disposable income per capita are the Northeast Economic Zone and Eastern Coastal Economic Zone, respectively. (3) Both the Theil index and Gini coefficient show that the overall carbon inequality is higher than income inequality; the Theil index decomposition indicates that city-level carbon inequality has declined; the key forces of carbon emission per capita and disposable income per capita inequality are inter-regional inequality (contribution rate: 55%–63%) and intra-regional inequality (contribution rate: 59%–63%), respectively. (4) Moreover, regarding income earners during 2015–2020 period, the top 10% of 321 cities occupy about 33% in the total national residential buildings' carbon emissions; the medium 40% of cities account for about 42% in total carbon emissions; in contrast, the bottom 50% of cities represent only about 25% of the total carbon emissions. These discoveries emphasize the necessity for the Chinese government to pay more attention to city-level residential building carbon emissions to track advances toward residents' sustainable lifestyles. • The city-level features of carbon emissions and resident incomes were analyzed. • Carbon and income inequality via Theil index and Gini coefficient were compared. • Carbon emission per capita inequality's core force via Theil index was identified. • Carbon inequality's disparities in economic zones and climate zones were discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Low-molecular-weight oyster peptides enhanced immune cell differentiation and immunoglobulin expression. • Low-molecular-weight oyster peptides increased the beneficial bacteria in the intestine. • Hydrophobic amino acids and glutamic acid may be main components effects of low-molecular-weight oyster peptides. Low-molecular-weight oyster peptides (LOPs) are typical bioactive peptides with ameliorated immunomodulatory properties. However, the mechanism underlying its effect on immune functions and intestinal flora after chemotherapy has not been reported. In this study, Lewis lung cancer mice were used along with cytotoxic chemotherapy to establish model to investigate the ameliorative effects of LOPs on immunomodulatory function and intestinal flora structure. Our results showed that administration of LOPs alleviated weight loss, reduced spleen tissue damage, increased splenic T -lymphocytes, and markedly increased secretion of serum immunoglobulins and decreased inflammatory factors. Additionally, LOPs significantly increased the abundance of beneficial bacteria (Lactobacillus and Coriobacteriaceae_UCG) and decreased pathogenic bacteria (Clostridium) present in intestine. Hydrophobic amino acids and glutamate may be the underlying components to mitigate negative effects of chemotherapy. This study provides a theoretical basis for the use of LOPs as a nutritional base for the development of formula foods for cancer patients undergoing chemotherapy. [ABSTRACT FROM AUTHOR]

Bi 2 Te 3 is a successful and commercial thermoelectric material. However, Bi 2 Te 3 is easily generates point defects, which limits its thermoelectric (TE) properties. This study presents a novel method to tune point defects by using short-range atomic diffusion via pulsed electric field (PEF) treatment in C-doped Bi 2 Te 3 films. The C atoms migrate from the interstitial position in the Bi layer (C i) and the Van der Waals gap (C vdw) to the Bi vacancy after the PEF treatment. For this case, it increases the content of the Te–C bonds for the PEF films, resulting in increased electron concentration. And the PEF can eliminate amorphous regions of the C-doped Bi 2 Te 3 films. In addition, the shorter bond length of the Te–C improves the compressive stress of the film and increases the effective mass of carriers. Thus, the conductivity and the Seebeck coefficient are improved simultaneously. In this study, the power factor was 2450.32 μW m−1·K−2 at 513 K after the PEF treatment. Therefore, the PEF is an effective method to improve TE properties by short-range atomic diffusion. [ABSTRACT FROM AUTHOR]

In this work, the competitive relationship between the double amorphous phases is systematically investigated to increase the high-temperature wear resistance of the self-lubricating TiAlSiCN coating. These double amorphous phases combine the SiN x phase with high-temperature resistance and the C-related phase with a low friction coefficient. An increase in the Si content facilitates the change in the phase composition. The resultant coating exhibits an adhesion strength of 153 N, a friction coefficient of 0.24 and a hardness of 25.24 GPa upon generation of the TiAlN(C), the SiN x and the C-related phase. In this case, the TiAlSiCN coating achieves long-term self-lubrication at high temperatures with the titanium alloy friction pair. This mechanism stems from the SiN x phase replacing the portion of the easily oxidized amorphous C-related phase, which yields an enhanced high-temperature wear resistance. The cutting distance of this TiAlSiCN is 120% higher than that of the TiAlCN during the high-speed cutting of the titanium alloy. This outcome provides an effective solution for high-temperature applications of self-lubricating coatings. • Long-term self-lubricating is remained in TiAlSiCN coating by optimal Si content. • Synergistic effect of amorphous SiN x and C-related phase is solved in TiAlSiCN. • Tool life of TiAlSiCN improved 225% by comparing with that of TiAlN. [ABSTRACT FROM AUTHOR]

The order-disorder transition (ODT) of RE zirconate (RE 2 Zr 2 O 7) has received much attention due to its potential applications in the design of thermal barrier coatings (TBCs). A series of high entropy RE zirconates (RE = La, Sm, Gd, Er and Lu) were designed and synthesized in order to regulate the fluorite-pyrochlore phases, and to investigate the effect of phase composition on the microstructures and performances. The results showed that the sintering temperature, as well as equivalent ion radius, played an important role in regulating the phase transformation of fluorite-pyrochlore. The coexistence of pyrochlore-fluorite phases not only can result in the decrease in grain size but also increased the lattice strain of each phase, thereby enhancing the phonon scattering and contributing to the reduction in the thermal conductivity. The CMAS corrosion resistance was mainly related to phase compositions, and the thicknesses of reaction layer decreased gradually with the increasing fluorite phase content. The results will provide theoretical guidance for the microstructural design of high entropy RE zirconates as next generation TBC materials in future. [ABSTRACT FROM AUTHOR]

Three kinds of high entropy (Y 0.25 Sc 0.25 Er 0.25 Yb 0.25) 2 Si 2 O 7 , (Y 0.2 Sc 0.2 Er 0.2 Yb 0.2 Lu 0.2) 2 Si 2 O 7 and (Y 0.2 Sc 0.2 Er 0.2 Yb 0.2 Gd 0.2) 2 Si 2 O 7 were designed and synthesized in order to investigate the relation of microstructures and CMAS corrosion resistance. At low temperature of 1300 °C, lattice distortion played a crucial role in resistance to CMAS corrosion, and larger lattice distortion contributed to CMAS corrosion resistance. However, the corrosion behavior at 1500 °C was related to the equivalent ionic radius and RE species. The smaller equivalent ionic radius tended to promote the re-precipitation of high entropy RE disilicate in residual CMAS glass rather than apatite. The results will provide theoretical guidance for the microstructural design of high entropy RE disilicate and selection of RE elements in future. • High entropy ceramics were synthesized by solid state reaction method. • (Y 0.2 Sc 0.2 Er 0.2 Yb 0.2 Gd 0.2) 2 Si 2 O 7 ceramics had a maximum lattice distortion. • (Y 0.2 Sc 0.2 Er 0.2 Yb 0.2 Gd 0.2) 2 Si 2 O 7 presented a best CMAS corrosion resistance. [ABSTRACT FROM AUTHOR]

The self-lubricating TiAlTaCN coating with high-temperature resistance above 800 °C is developed using magnetron sputtering. This mechanism stems from the TaN phase is easily oxidized to form a protective Ta 2 O 5 that compensates for the insufficient antioxidant capacity of Al 2 O 3. Moreover, the TaC phase, being resistant to oxidation, contributes to achieving the self-lubrication effect with amorphous C-related phases. The cutting distance of the TiAlTaCN is 250% greater than that of the TiAlCN during the high-speed cutting of titanium alloy. These results reveal the oxidation mechanism of different carbon nitrides and provide a new solution for the self-lubricating coatings applied at high temperatures. • A new high-temperature resistant (800 °C) self-lubricating (COF=0.27) TiAlTaCN nanocomposite coating was prepared. • The Ta addition inhibits the phase transition and increases the high thermal stability from 600 °C to 1000 °C. • The wear rate of the TiAlTaCN is 38.7% lower than that of the TiAlCN at 600 °C. • The cutting distance of the TiAlTaCN is 250% higher than the TiAlCN during the high-speed cutting of titanium alloy. [ABSTRACT FROM AUTHOR]

The novel rare earth monosilicates (xRE 1/x) 2 SiO 5 (RE=Yb, Tm, Er, Y, Dy and Tb, x = 2–6) were prepared in order to establish the relationship between configurational entropy and lattice distortion, and the effect of configurational entropy on their properties was investigated. The results showed that the lattice distortion of (xRE 1/x) 2 SiO 5 increased gradually with the increase of configurational entropy, but the multi-principal component solid solution tended to form a highly symmetrical crystal structure when the configurational entropy was large enough, thus inhibiting the lattice distortion. (5RE 1/5) 2 SiO 5 had a maximum lattice distortion, which leaded to a relatively low thermal conductivity and coefficient of thermal expansion, and good CMAS corrosion resistance. • The effect of configurational entropy on microstructure and properties was investigated. • (5RE 0.2) 2 SiO 5 ceramic had a maximum lattice distortion. • (5RE 0.2) 2 SiO 5 ceramic presented the relatively good thermal properties and CMAS corrosion resistance. [ABSTRACT FROM AUTHOR]