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In recent years, all-inorganic perovskites CsPbX3 (X = Cl, Br, I) have emerged as excellent candidates for solar cells due to their remarkable thermal stability and suitable bandgaps. Among them, CsPbI2Br is a hotspot in perovskite material research currently. Non-radiative electron–hole recombination often leads to significant energy losses, impacting the efficiency of solar cells, so a thorough understanding of carrier recombination mechanisms is crucial. Our work investigated the carrier recombination dynamics in detail and proved that strains can effectively reduce nonradiative recombination. In this study, using first-principles calculations combined with nonadiabatic (NA) molecular dynamics (MD), we demonstrate that applying 2% tensile and 2% compressive strains to CsPbI2Br can modify the bandgap, induce moderate disorder, reduce the overlap of electron–hole wavefunctions, decrease NA coupling, and shorten decoherence time, thereby minimizing non-radiative recombination and extending the carrier lifetime. Especially the 2% tensile strain exhibits more effective control performance, significantly reducing non-radiative electron–hole recombination and extending the charge carrier lifetime to 14.59 ns, nearly five times that of the pristine CsPbI2Br system (3.12 ns). This study reveals the impact mechanism of strain on carrier behavior in perovskite solar cells, providing a new non-chemical strategy for modulating the lifetime of photo-generated carriers and enhancing the efficiency of all-inorganic perovskite solar cells. [ABSTRACT FROM AUTHOR]

In response to the issues of low outdoor thermal comfort and poor ventilation environment in Beijing Hutong, this paper proposes a rapid intelligent optimization method combining Pix2Pix (Image-to-Image Translation with Conditional Adversarial Networks) with a genetic algorithm. Firstly, the architectural types of the research objects are highly refined and summarized into four traditional building types. Then, they are placed in the site with open spaces in a certain proportion, and a multi-objective optimization model for the UTCI (Universal Thermal Climate Index) and building area is constructed using a genetic algorithm, generating and iteratively optimizing the spatial layout of the building population. Finally, Pix2Pix is used to learn and train a large number of Hutong combination samples, rapidly generating the UTCI and ventilation results, which serve as the optimization objectives to obtain the optimal solution set for Hutong spatial forms. Compared with traditional empirical design methods, this method allows for a rapid and efficient traversal of vast solution spaces, intelligently generating Hutong renovation schemes that balance cultural heritage and healthy comfort. The research results demonstrate that this method can quickly find (26.4 times faster than traditional performance simulation methods) that the reasonable proportions of Siheyuan, Sanheyuan, Erheyuan, new buildings, and empty spaces in the Da Yuan Hutong in Beijing should be controlled at 11.8%, 16.9%, 23.8%, 33.8%, and 13.7%, respectively. Meanwhile, the building density should be maintained between 0.5 and 0.58, and the floor area ratio should be kept between 0.96 and 1.14. This significantly improves outdoor comfort, enhances the living environment of the Hutong, and promotes sustainable urban development. [ABSTRACT FROM AUTHOR]

The rare‐earth chalcogenide Er2Te3, characterized by its low lattice thermal conductivity, represents a highly promising and innovative thermoelectric material. However, there have been limited studies exploring its thermoelectric properties in depth. Additionally, it has been discovered that strain engineering is an effective method for enhancing thermoelectric properties, a technique successfully applied to relevant materials. In this study, we employed a first‐principles approach in conjunction with the semi‐classical Boltzmann transport theory to investigate the thermoelectric properties of Er2Te3 materials under −4% to 4% strain. The results indicate that applying compressive strain modulates thermoelectric properties more effectively than tensile strain for Er2Te3. Under strain modulation, the maximum power factor for both p‐type and n‐type Er2Te3 increases significantly, from 0.9 to 2.5 mW m−1 K−2 and from 14 to 18 mW m−1 K−2 at 300 K, respectively. Moreover, the figure of merit (ZT) for p‐type and n‐type Er2Te3 improves notably, from 0.15 to 0.25 and from 1.15 to 1.35, respectively, under −4% strain. Consequently, the thermoelectric properties of Er2Te3 materials can be significantly enhanced through strain application, with n‐type Er2Te3 demonstrating substantial potential as a thermoelectric material. [ABSTRACT FROM AUTHOR]

Background: With two well‐validated aging measures capturing mortality and morbidity risk, this study examined whether and to what extent aging mediates the associations of unhealthy lifestyles with adverse health outcomes. Methods: Data were from 405,944 adults (40–69 years) from UK Biobank (UKB) and 9972 adults (20–84 years) from the US National Health and Nutrition Examination Survey (NHANES). An unhealthy lifestyles score (range: 0–5) was constructed based on five factors (smoking, drinking, physical inactivity, unhealthy body mass index, and unhealthy diet). Two aging measures, Phenotypic Age Acceleration (PhenoAgeAccel) and Biological Age Acceleration (BioAgeAccel) were calculated using nine and seven blood biomarkers, respectively, with a higher value indicating the acceleration of aging. The outcomes included incident cardiovascular disease (CVD), incident cancer, and all‐cause mortality in UKB; CVD mortality, cancer mortality, and all‐cause mortality in NHANES. A general linear regression model, Cox proportional hazards model, and formal mediation analysis were performed. Results: The unhealthy lifestyles score was positively associated with PhenoAgeAccel (UKB: β = 0.741; NHANES: β = 0.874, all p < 0.001). We further confirmed the respective associations of PhenoAgeAccel and unhealthy lifestyles with the outcomes in UKB and NHANES. The mediation proportion of PhenoAgeAccel in associations of unhealthy lifestyles with incident CVD, incident cancer, and all‐cause mortality were 20.0%, 17.8%, and 26.6% (all p < 0.001) in UKB, respectively. Similar results were found in NHANES. The findings were robust when using another aging measure—BioAgeAccel. Conclusions: Accelerated aging partially mediated the associations of lifestyles with CVD, cancer, and mortality in UK and US populations. The findings reveal a novel pathway and the potential of geroprotective programs in mitigating health inequality in late life beyond lifestyle interventions. [ABSTRACT FROM AUTHOR]

The lead-free halide double perovskite material A2BB’X6 represented by Cs2AgBiBr6, has higher potential as a photovoltaic material since it has good electronic and optical properties in recent years. However, the highest power conversion efficiency (PCE) achieved for solar cells made with Cs2AgBiBr6 as the light-absorbing layer in experiments is only 2.51%. To investigate this phenomenon, we used the Solar Cell Capacitance Simulator (SCAPS) simulation software to build five solar cell models with the structure of FTO/ZnO/Light-absorbing layer/Cu2O/Au based on different light-absorption layer materials. Two reasons causing the low PCE of Cs2AgBiBr6 solar cells were identified. On the one hand, interlayer defects in Cs2AgBiBr6 film synthesis significantly decreased the fill factor (FF), thereby reducing the quantum efficiency (QE). On the other hand, Cs2AgBiBr6’s larger indirect bandgap resulted in a narrower absorption range. Additionally, it was demonstrated that adjusting the material thickness and alloying method could, respectively, improve the two aforementioned issues. When the thickness of the light-absorbing layer material was 300nm, the FF increased from 39.88% to 55.01%, resulting in an optimal PCE of 3.88% for the solar cell. Alloying increased the short-circuit current (JSC) from 8.44mA/cm2 to 21.24mA/cm2, leading to a simulated PCE increase of 8.92% for solar cells based on Cs2NaSb0.5In0.5I6. This work, from the perspective of device simulation, is highly significant for improving the photoelectric conversion efficiency of Cs2AgBiBr6-based perovskite solar cells in experimental settings. It offers new insights for optimizing solar cell efficiency. [ABSTRACT FROM AUTHOR]

In recent years, all-inorganic perovskites CsPbX 3 (X = Cl, Br, I) have emerged as excellent candidates for solar cells due to their remarkable thermal stability and suitable bandgaps. Among them, CsPbI 2 Br is a hotspot in perovskite material research currently. Non-radiative electron-hole recombination often leads to significant energy losses, impacting the efficiency of solar cells, so a thorough understanding of carrier recombination mechanisms is crucial. Our work investigated the carrier recombination dynamics in detail and proved that strains can effectively reduce nonradiative recombination. In this study, using first-principles calculations combined with nonadiabatic (NA) molecular dynamics (MD), we demonstrate that applying 2% tensile and 2% compressive strains to CsPbI 2 Br can modify the bandgap, induce moderate disorder, reduce the overlap of electron-hole wavefunctions, decrease NA coupling, and shorten decoherence time, thereby minimizing non-radiative recombination and extending the carrier lifetime. Especially the 2% tensile strain exhibits more effective control performance, significantly reducing non-radiative electron-hole recombination and extending the charge carrier lifetime to 14.59 ns, nearly five times that of the pristine CsPbI 2 Br system (3.12 ns). This study reveals the impact mechanism of strain on carrier behavior in perovskite solar cells, providing a new non-chemical strategy for modulating the lifetime of photo-generated carriers and enhancing the efficiency of all-inorganic perovskite solar cells.