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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]

In this study, we explored the role of the intrinsic defects on the tuning thermoelectric (TE) performance of Al-doped ZnO (ZnO:Al) films. The intrinsic defects of the Zn interstitial (Zn i) and the oxygen vacancy (V O) were controlled by varying the Zn content by using the radio frequency atomic source vacuum evaporation method. In the Zn-rich case, the excessive Zn formed Zn i to provide most of the carriers. V O became the main origin of the carriers with a decreasing Zn content. When the Zn content was 55.2% and 52.5%, the segregation of Zn i decreased the carrier concentration and subsequently, enhanced the resistivity and the Seebeck coefficient. The ZnO:Al film with a Zn content of 52.5% had the highest power factor of 274.03 μW·m−1·K−2 at 819 K. In addition, the higher Zn i concentration had a more prominent effect on thermal conductivity. The thermal conductivity increased to 1.756 W·m−1·K−1 from 0.608 W·m−1·K−1 with the Zn content decreasing from 55.2% to 50.6%. The ZT value reached the highest of 0.121 when the film had the optimum Zn concentration of 51.5%. This study concluded that the tuning of the intrinsic defects was an effective method to enhance the TE performance. [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]

Unstable nanosheet morphology of polycrystalline SnSe film becomes a limitation for its application in the field of waste heat recovery. This study dopes Co into the evaporated SnSe film to smooth the surface and to improve power factor. The results show that Co dopant makes the rough nanosheet change to surface densely packed structure. The dopant Co forms Co particles distributing around SnSe grain boundary, which suppress SnSe (011) plane growth and subsequent reduce nanosheet formation. In addition, Co dopant increases electric conductivity through increasing the carrier concentration, but the magnetism of Co particles decreases carrier mobility due to spin-charge coupling and also affects the Seebeck coefficient. The power factor thus is improved after doped Co. This study presents a method to fabricate polycrystalline SnSe film with smooth surface morphology and high power factor. [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]

Summary: Excessive secretion of glucagon is a major contributor to the development of diabetic hyperglycemia. Secretion of glucagon is regulated by various nutrients, with glucose being a primary determinant of the rate of α cell glucagon secretion. The intra-islet action of insulin is essential to exert the effect of glucose on the α cells since, in the absence of insulin, glucose is not able to suppress glucagon release in vivo. However, the precise mechanism by which insulin suppresses glucagon secretion from α cells is unknown. In this study, we show that insulin induces activation of GABAA receptors in the α cells by receptor translocation via an Akt kinase-dependent pathway. This leads to membrane hyperpolarization in the α cells and, ultimately, suppression of glucagon secretion. We propose that defects in this pathway(s) contribute to diabetic hyperglycemia. [Copyright &y& Elsevier]

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]

Tool coatings with a high coefficient of friction (COF) form a built-up edge between the tool and the piece of work when cutting titanium alloy, creating a high cutting temperature, decreased tool life, and lowing the cutting quality. TiAlN/WS self-lubricating composite coatings with high adhesion were prepared via the multilayer growth of WS with low COF and TiAlN with high wear resistance. The TiAlN/WS coating had high adhesion (135.4 N), low COF (0.261), and unchanged hardness (14 GPa). The low COF and high wear resistance originated from the self-lubricating wear-resistance debris at the micron scale with TiAlN coated with amorphous WS. The coating reduced the adhesive wear. By comparing the machining results of the TiAlN/WS coating with those of the TiAlN coating, the flank wear was 45.9% lower for the same cutting length, the machining speed increased from 41 m/min to 100 m/min, the cutting length was over 200% higher at the same flank wear of 0.3, and the self-lubricating composite coating showed good results under dry cutting conditions. Therefore, this coating provides a method for use in high-speed and environmentally-friendly machines for difficult-to-cut materials. [ABSTRACT FROM AUTHOR]

Background: Aortic valve area (AVA) ≤1.0 cm2 is a defining characteristic of severe aortic stenosis (AS). AVA can be underestimated at low transvalvular flow rate. Yet, the impact of flow rate on prognostic value of AVA ≤1.0 cm2 is unknown and is not incorporated into AS assessment.Objectives: This study aimed to evaluate the effect of flow rate on prognostic value of AVA in AS.Methods: In total, 1,131 patients with moderate or severe AS and complete clinical follow-up were included as part of a longitudinal database. The effect of flow rate (ratio of stroke volume to ejection time) on prognostic value of AVA ≤1.0 cm2 for time to death was evaluated, adjusting for confounders. Sensitivity analysis was performed to identify the optimal cutoff for prognostic threshold of AVA. The findings were validated in a separate external longitudinal cohort of 939 patients.Results: Flow rate had a significant effect on prognostic value of AVA. AVA ≤1.0 cm2 was not prognostic for mortality (p = 0.15) if AVA was measured at flow rates below median (≤242 ml/s). In contrast, AVA ≤1.0 cm2 was highly prognostic for mortality (p = 0.003) if AVA was measured at flow rates above median (>242 ml/s). Findings were irrespective of multivariable adjustment for age, sex, and surgical/transcatheter aortic valve replacement (as time-dependent covariates); comorbidities; medications; and echocardiographic features. AVA ≤1.0 cm2 was also not an independent predictor of mortality below median flow rate in the validation cohort. The optimal flow rate cutoff for prognostic threshold was 210 ml/s.Conclusions: Transvalvular flow rate determines prognostic value of AVA in AS. AVA measured at low flow rate is not a good prognostic marker and therefore not a good diagnostic marker for truly severe AS. Flow rate assessment should be incorporated into clinical diagnosis, classification, and prognosis of AS. [ABSTRACT FROM AUTHOR]

Background: There is a need for improved methods for detection and risk stratification of myocarditis associated with immune checkpoint inhibitors (ICIs). Global longitudinal strain (GLS) is a sensitive marker of cardiac toxicity among patients receiving standard chemotherapy. There are no data on the use of GLS in ICI myocarditis.Objectives: This study sought to evaluate the role of GLS and assess its association with cardiac events among patients with ICI myocarditis.Methods: This study retrospectively compared echocardiographic GLS by speckle tracking at presentation with ICI myocarditis (cases, n = 101) to that from patients receiving an ICI who did not develop myocarditis (control subjects, n = 92). Where available, GLS was also measured pre-ICI in both groups. Major adverse cardiac events (MACE) were defined as a composite of cardiogenic shock, arrest, complete heart block, and cardiac death.Results: Cases and control subjects were similar in age, sex, and cancer type. At presentation with myocarditis, 61 cases (60%) had a normal ejection fraction (EF). Pre-ICI, GLS was similar between cases and control subjects (20.3 ± 2.6% vs. 20.6 ± 2.0%; p = 0.60). There was no change in GLS among control subjects on an ICI without myocarditis (pre-ICI vs. on ICI, 20.6 ± 2.0% vs. 20.5 ± 1.9%; p = 0.41); in contrast, among cases, GLS decreased to 14.1 ± 2.8% (p < 0.001). The GLS at presentation with myocarditis was lower among cases presenting with either a reduced (12.3 ± 2.7%) or preserved EF (15.3 ± 2.0%; p < 0.001). Over a median follow-up of 162 days, 51 (51%) experienced MACE. The risk of MACE was higher with a lower GLS among patients with either a reduced or preserved EF. After adjustment for EF, each percent reduction in GLS was associated with a 1.5-fold increase in MACE among patients with a reduced EF (hazard ratio: 1.5; 95% confidence interval: 1.2 to 1.8) and a 4.4-fold increase with a preserved EF (hazard ratio: 4.4; 95% confidence interval: 2.4 to 7.8).Conclusions: GLS decreases with ICI myocarditis and, compared with control subjects, was lower among cases presenting with either a preserved or reduced EF. Lower GLS was strongly associated with MACE in ICI myocarditis presenting with either a preserved or reduced EF. [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]

Abstract In order to study the fatigue characteristics and oxidation characteristics of 38MnVS6 and 42CrMo4, two kinds of forging steel piston materials, under high temperature and high load conditions, the temperature field, fatigue safety coefficient and distribution of surface oxygen layer were compared and analyzed by means of material characteristics detection, calculation of finite element numerical simulation and bench test and so on. Results showed that forging fiber lines of both two kinds of forged steel pistons could meet the process requirements. However, as for the basic characteristic values, the 42CrMo4 piston was better than the 38MnVS6 piston, increasing by 10% approximately on performance values. Besides, the maximum of temperature of the two pistons both appeared around the corner on the top of combustion chamber, and the temperature of the 38MnVS6 piston was even higher. After combining the basic characteristic, the average fatigue safety coefficient of the 42CrMo4 piston in the combustion chamber and the cooling gallery was more important than that of the 38MnVS6 piston, increasing by 3.6–7%. In addition, under the action of high temperature and pressure, obvious surface oxidation was produced on the top of the pistons. Meanwhile, a certain carbon deposit was also formed on the top of cooling galleries. In general, due to the difference of temperature distribution and thermal conductivity, the oxidation and carbon deposition phenomenon of the 42CrMo4 piston was significantly weaker than that of the 38MnVS6 piston the maximum optimization value of which even reached 90%. Highlights • Real engine test was employed to estimate the fatigue characteristics and oxidation characteristics of steel piston material. • The average fatigue safety coefficient of the 42CrMo4 piston was higher. • The oxidation and carbon deposition phenomenon of the 42CrMo4 piston was lighter. [ABSTRACT FROM AUTHOR]

In order to distinguish the contribution of various chemical states in the Co-doped ZnO film on the ferromagnetism, the films were prepared by oxidizing as-deposited Co-Zn films fabricated by molecular beam vapor deposition method. Different growth modes of multilayer, co-deposition, and bilayer of the Co-Zn films and oxidization temperature of 300 or 600 °C were used to control the cobalt states of Co metal, cobalt oxide, Co ion in the ZnO lattice and the defects of oxygen vacancy in the films. The insufficient oxidization at 300 °C leads to the aggregation of Co metal. The Co metal features ferromagnetism in the films of the three growth modes. After the films oxidized at 600 °C, the Co ions are predominant in the co-deposition film. The oxygen vacancies are predominant for the bilayer film. Meanwhile, a small amount of cobalt oxide is formed in the co-deposition films. However, no ferromagnetism is observed at room temperature for all the films oxidized at 600 °C. This means that the cobalt oxide, Co ion, and oxygen vacancy cannot improve the RT ferromagnetism. When the measurement temperature decreases to − 150 °C, the ferromagnetism appears in the bilayer film due to the oxygen vacancy. The weak magnetism presents in the co-deposition film because of the Co ions indicating that the oxygen vacancy is more significant in obtaining ferromagnetism than the Co ions. [ABSTRACT FROM AUTHOR]

Room temperature ferromagnetism (RTFM) is detected in the Co doped ZnO films, which are formed via the thermal oxidation of electrodeposited Co/Zn bilayers. The effect of oxidation temperature on the origin of RTFM is examined. Results indicate that various contents of Co 2+ dopants, Zn x Co 3−x O 4 clusters, O vacancy and Zn interstitial are achieved in the films oxidized at 400 and 550 °C. The amount of O vacancy decreases sharply with increasing oxidation temperature. This leads to the saturation magnetization of films oxidized at 400 °C is higher than that of films oxidized at 550 °C. This indicates that the effect of O vacancy on ferromagnetism is more prominent in the Co doped ZnO films. [ABSTRACT FROM AUTHOR]