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Optically addressable spin defects in three-dimensional (3D) crystals and two-dimensional (2D) van der Waals (vdW) materials are revolutionizing nanoscale quantum sensing. Spin defects in one-dimensional (1D) vdW nanotubes will provide unique opportunities due to their small sizes in two dimensions and absence of dangling bonds on side walls. However, optically detected magnetic resonance of localized spin defects in a nanotube has not been observed. Here, we report the observation of single spin color centers in boron nitride nanotubes (BNNTs) at room temperature. Our findings suggest that these BNNT spin defects possess a spin S = 1/2 ground state without an intrinsic quantization axis, leading to orientation-independent magnetic field sensing. We harness this unique feature to observe anisotropic magnetization of a 2D magnet in magnetic fields along orthogonal directions, a challenge for conventional spin S = 1 defects such as diamond nitrogen-vacancy centers. Additionally, we develop a method to deterministically transfer a BNNT onto a cantilever and use it to demonstrate scanning probe magnetometry. Further refinement of our approach will enable atomic scale quantum sensing of magnetic fields in any direction. Optically addressable spin defects, such as the NV centre in diamond, have enabled the nanoscale measurement of external stimuli. Here, Gao, Vaidya and coauthors observe a single spin colour centres in boron nitride nanotubes, which, due to their spin S = 1/2 ground state, allow for omnidirectional magnetic field sensing. ' [ABSTRACT FROM AUTHOR]

High-entropy materials consisting of disordered multiple components can exhibit enhanced materials properties compared with their individual constituents. Although various high-entropy materials have been developed based on the configurational disorder of mixed inorganic components, the potential of organic moieties for high-entropy structures remains underexplored. Here we report a family of high-entropy organic–inorganic hybrid perovskites for photovoltaic applications. By mixing different A-site organic cations with various alkyl chains, we obtain a hybrid crystal structure with ordered inorganic frameworks and disordered organic moieties, leading to increased entropy. The hybrid perovskite exhibits superior properties compared with its single-component counterpart, including increased resilience to structural transitions and heat stress. When used in solar cells, the high-entropy hybrid perovskite leads to devices with a power conversion efficiency of 25.7% (certified, 25.5%) for an inverted-cell architecture. Cells retain over 98% of their initial power conversion efficiency after 1,000 h of operation under continuous illumination (AM 1.5 G), with a linear extrapolation to the T90 value of 5,040 h. In particular, the structural disorder of this class of high-entropy materials can also reduce non-radiative recombinations for a wide range of perovskite composition, stoichiometry deviation, film-processing history and device architecture. This universal and error-tolerant strategy can, thus, benefit the production yield of perovskite solar cells in future industrial mass production. Given the rich chemistry of organic moieties and mixing configuration, this work may also open up more opportunities to tune the stability and optoelectronic properties of perovskite materials for photoelectric applications. High-entropy hybrid perovskites exhibit improved materials properties compared with their individual components. When employed in solar cells, champion devices achieve a certified power conversion efficiency of 25.5% and an extrapolated T90 lifetime of over 5,000 h under continuous light soaking. [ABSTRACT FROM AUTHOR]

Area detectors have been widely used in X-ray diffraction (XRD) to improve the acquisition speed and data quality. Here, an accurate, high efficiency, low distortion approach with a large angle range for collecting powder X-ray diffraction data is developed which is carried out by rotating a small area detector on the detector arm of the diffractometer. A series of collected images are spliced and converted into one 1D XRD pattern. The calculation of the 2θ value and intensity corresponding to every pixel are shown in detail. The calibration of the detector and experimental geometry was carried out. Finally, the reliability of this method has been demonstrated by the X-ray diffraction measurements of a standard LaB6 powder and Rietveld refinement results. [ABSTRACT FROM AUTHOR]

The mechanical durability and efficiency of all‐inorganic flexible perovskite solar cells (f‐PSCs) still require enhancement for practical applications. In this study, a creative debridement strategy to improve the mechanical durability and photovoltaic performance of all‐inorganic f‐PSCs by pre‐bending the flexible perovskite film and then depositing the passivation agent 2‐mercaptopyridine is proposed. The pre‐bending process induced the generation of microcracks in the perovskite film surface, and 2‐mercaptopyridine can more effectively penetrate the interior of the film through the microcracks, thereby further passivating deep surface defects. These microcracks and defects can be perfectly repaired by 2‐mercaptopyridine. Bidentate coordination sites of S and N in 2‐mercaptopyridine show stronger binding energy with surface defects. The debridement strategy effectively enhanced the crystallization of the film surface and markedly inhibited crack propagation during the film's bending process. The optimized device achieves a champion power conversion efficiency (PCE) of 14.74%. The pre‐bent and passivated all‐inorganic f‐PSC shows 104% of its initial PCE after 15 000 bending cycles at a curvature radius of 3 mm. Remarkably, even after undergoing 70 000 bending cycles at a curvature radius of 5 mm, pre‐bent, and passivated f‐PSC can retain over 93% of its initial PCE, exhibiting excellent mechanical durability. [ABSTRACT FROM AUTHOR]

The senescence of bone marrow mesenchymal stromal cells (MSCs) leads to the impairment of stemness and osteogenic differentiation capacity. In a previous study, we screened out stearoyl-CoA desaturase 2 (SCD2), the most evidently changed differential gene in lipid metabolism, using combined transcriptomic and metabolomic analyses, and verified that SCD2 could mitigate MSC senescence. However, the underlying molecular mechanism by which the rate-limiting enzyme of lipogenesis SCD2 manipulates MSC senescence has not been completely understood. In this study, we demonstrate that SCD2 over-expression alleviates MSC replicative senescence and ameliorates their osteogenic differentiation through the regulation of lipogenesis. Furthermore, SCD2 expression is reduced, whereas miR-200c-3p expression is elevated in replicative senescent MSCs. SCD2 is the direct target gene of miR-200c-3p, which can bind to the 3′-UTR of SCD2. MiR-200c-3p replenishment in young MSCs is able to diminish SCD2 expression levels due to epigenetic modulation. In addition, SCD2-rescued MSC senescence and enhanced osteogenic differentiation can be attenuated by miR-200c-3p repletion via suppressing lipogenesis. Taken together, we reveal the potential mechanism of SCD2 influencing MSC senescence from the perspective of lipid metabolism and epigenetics, which provides both an experimental basis for elucidating the mechanism of stem cell senescence and a novel target for delaying stem cell senescence. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stem cells (MSCs) are one of the most widely studied adult stem cells, while MSC replicative senescence occurs with serial expansion in vitro. We determined whether miR-34a can regulate MSC senescence by directly targeting glycolytic key enzymes to influence glycolysis. Methods: Detected the effects of miR-34a on MSC senescence and glycolytic metabolism through gene manipulation. Bioinformatics prediction and luciferase reporter assay were applied to confirm that HK1 is a direct target of miR-34a. The underlying regulatory mechanism of miR-34a targeting HK1 in MSC senescence was further explored by a cellular function recovery experiment. Results: In the current study, we revealed that miR-34a over-expression exacerbated senescence-associated characteristics and impaired glycolytic metabolism. Then we identified hexokinase1 (HK1) as a direct target gene of miR-34a. And HK1 replenishment reversed MSC senescence and reinforced glycolysis. In addition, miR-34a-mediated MSC senescence and lower glycolytic levels were evidently rescued following the co-treatment with HK1 over-expression. Conclusion: The miR-34a-HK1 signal axis can alleviate MSC senescence via enhancing glycolytic metabolism, which possibly provides a novel mechanism for MSC senescence and opens up new possibilities for delaying and suppressing the occurrence and development of aging and age-related diseases. [ABSTRACT FROM AUTHOR]

Two‐dimensional materials have been widely used to tune the growth and energy‐level alignment of perovskites. However, their incomplete passivation and chaotic usage amounts are not conducive to the preparation of high‐quality perovskite films. Herein, we succeeded in obtaining higher‐quality CsPbBr3 films by introducing large‐area monolayer graphene as a stable physical overlay on top of TiO2 substrates. Benefiting from the inert and atomic smooth graphene surface, the CsPbBr3 film grown on top by the van der Waal epitaxy has higher crystallinity, improved (100) orientation, and an average domain size of up to 1.22 μm. Meanwhile, a strong downward band bending is observed at the graphene/perovskite interface, improving the electron extraction to the electron transport layers (ETL). As a result, perovskite film grown on graphene has lower photoluminescence (PL) intensity, shorter carrier lifetime, and fewer defects. Finally, a photovoltaic device based on epitaxy CsPbBr3 film is fabricated, exhibiting power conversion efficiency (PCE) of up to 10.64% and stability over 2000 h in the air. [ABSTRACT FROM AUTHOR]

The article delves into the efficacy of Sampled Softmax (SSM) loss in item recommendation, emphasizing its advantages over conventional pointwise and pairwise losses. It addresses key questions regarding the suitability of SSM loss for recommendation tasks and examines its conceptual benefits. Topics include its ability to mitigate popularity bias, facilitate informative gradient mining, and enhance top-K performance, shedding light on its potential to revolutionize recommendation systems.

Perturbation theory (PT) might be one of the most powerful and fruitful tools for both physicists and chemists, which has led to a wide variety of applications. Over the past decades, advances in quantum computing provide opportunities for alternatives to classical methods. Recently, a general quantum circuit estimating the low order PT corrections has been proposed. In this article, we revisit the quantum circuits for PT calculations, and develop the methods for higher order PT corrections of eigenenergy, especially the 3rd and 4th order corrections. We present the feasible quantum circuit to estimate each term in these PT corrections. There are two the fundamental operations in the proposed circuit. One approximates the perturbation terms, the other approximates the inverse of unperturbed energy difference. The proposed method can be generalized to higher order PT corrections. [ABSTRACT FROM AUTHOR]

Levitated diamond particles in high vacuum with internal spin qubits have been proposed for exploring macroscopic quantum mechanics, quantum gravity, and precision measurements. The coupling between spins and particle rotation can be utilized to study quantum geometric phase, create gyroscopes and rotational matter-wave interferometers. However, previous efforts in levitated diamonds struggled with vacuum level or spin state readouts. To address these gaps, we fabricate an integrated surface ion trap with multiple stabilization electrodes. This facilitates on-chip levitation and, for the first time, optically detected magnetic resonance measurements of a nanodiamond levitated in high vacuum. The internal temperature of our levitated nanodiamond remains moderate at pressures below 10−5 Torr. We have driven a nanodiamond to rotate up to 20 MHz (1.2 × 109 rpm), surpassing typical nitrogen-vacancy (NV) center electron spin dephasing rates. Using these NV spins, we observe the effect of the Berry phase arising from particle rotation. In addition, we demonstrate quantum control of spins in a rotating nanodiamond. These results mark an important development in interfacing mechanical rotation with spin qubits, expanding our capacity to study quantum phenomena. Levitated nanodiamonds containing NV centers promise applications in quantum technologies, but they require experiments in high vacuum. Here the authors report on-chip levitation of nanodiamonds in high vacuum using a surface ion trap, showing spin read-out and fast rotation above NV center spin dephasing time. [ABSTRACT FROM AUTHOR]

Due to the complex interactions between multiple infectious diseases, the spreading of diseases in human bodies can vary when people are exposed to multiple sources of infection at the same time. Typically, there is heterogeneity in individuals' responses to diseases, and the transmission routes of different diseases also vary. Therefore, this paper proposes an SIS disease spreading model with individual heterogeneity and transmission route heterogeneity under the simultaneous action of two competitive infectious diseases. We derive the theoretical epidemic spreading threshold using quenched mean-field theory and perform numerical analysis under the Markovian method. Numerical results confirm the reliability of the theoretical threshold and show the inhibitory effect of the proportion of fully competitive individuals on epidemic spreading. The results also show that the diversity of disease transmission routes promotes disease spreading, and this effect gradually weakens when the epidemic spreading rate is high enough. Finally, we find a negative correlation between the theoretical spreading threshold and the average degree of the network. We demonstrate the practical application of the model by comparing simulation outputs to temporal trends of two competitive infectious diseases, COVID-19 and seasonal influenza in China. [ABSTRACT FROM AUTHOR]

Highlights: High-quality large-area perovskite films are prepared using a solid–liquid two-step film formation method combined with CsBr modification for the buried interface and Urea additive for perovskite crystallization. The inverted perovskite solar modules' performance is enhanced to 20.56% in 61.56 cm2 with improved stability. A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells. The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs. In this work, we adopted a solid–liquid two-step film formation technique, which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films. This method possesses the advantages of integrating vapor deposition and solution methods, which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform, large-area perovskite film. Furthermore, modification of the NiOx/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization. As a result, a large-area perovskite film possessing larger grains, fewer pinholes, and reduced defects could be achieved. The inverted PSM with an active area of 61.56 cm2 (10 × 10 cm2 substrate) achieved a champion power conversion efficiency of 20.56% and significantly improved stability. This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication. [ABSTRACT FROM AUTHOR]

The addition of methylammonium chloride (MACl) significantly improves the performance and stability of perovskite fabricated by two-step processes. However, its role in crystallization dynamics has not been thoroughly studied. In this work, a comparison study is carried out using different additions of MACl to investigate the impact of the perovskite crystallization dynamics. In situ grazing incidence wide-angle X-ray scattering (GIWAXS) observations during the annealing process of perovskite revealed that the amount of MACl significantly influences the crystallinity and orientation of the perovskite. Increasing the MACl addition enhances the crystallinity of the perovskite in the wet film's intermediate phase and strengthens the out-of-plane orientation of the FAPbI3 perovskite α-phase (001) planes during annealing. Moreover, it was found that both excessive and insufficient amounts of MACl introduce defects into the perovskite, which are detrimental to device performance. In contrast, an optimal ratio of MACl-9 mg leads to the formation of uniform and large-grained FAPbI3 perovskite films, with the longest carrier lifetimes (163.7 ns) compared to MACl-5 mg (68.4 ns) and MACl- 13 mg (120.1 ns). As a result, the fabricated MACl-9 mg-based solar cell achieved the highest efficiency (22.63%), which is higher than those of MACl-5 mg (21.47%) and MACl-13 mg (20.07%). [ABSTRACT FROM AUTHOR]

The treadmill exercise test (TET) serves as a non-invasive method for the diagnosis of coronary artery disease (CAD). Despite its widespread use, TET reports are susceptible to external influences, heightening the risk of misdiagnosis and underdiagnosis. In this paper, we propose a novel automatic CAD diagnosis approach. The proposed approach introduces a customized preprocessing method to obtain clear electrocardiograms (ECGs) from individual TET reports. Additionally, it presents TETDiaNet, a novel neural network designed to explore the temporal relationships within TET ECGs. Central to TETDiaNet is the TETDia block, which mimics clinicians' diagnostic processes to extract essential diagnostic information. This block encompasses an intra-state contextual learning module and an inter-state contextual learning module, modeling the temporal relationships within a single state and between states, respectively. These two modules help the TETDia block to capture effective diagnosis information by exploring the temporal relationships within TET ECGs. Furthermore, we establish a new TET dataset named TET4CAD for CAD diagnosis. It contains simplified TET reports for 192 CAD patients and 224 non-CAD patients, and each patient undergoes coronary angiography for labeling. Experimental results on TET4CAD underscore the superior performance of the proposed approach, highlighting the discriminative value of the temporal relationships within TET ECGs for CAD diagnosis. [ABSTRACT FROM AUTHOR]

While the monolayer sheet is well-established as a Mott-insulator with a finite energy gap, the insulating nature of bulk 1T-TaS2 crystals remains ambiguous due to their varying dimensionalities and alterable interlayer coupling. In this study, we present a unique approach to unlock the intertwined two-dimensional Mott-insulator and three-dimensional band-insulator states in bulk 1T-TaS2 crystals by structuring a laddering stack along the out-of-plane direction. Through modulating the interlayer coupling, the insulating nature can be switched between band-insulator and Mott-insulator mechanisms. Our findings demonstrate the duality of insulating nature in 1T-TaS2 crystals. By manipulating the translational degree of freedom in layered crystals, our discovery presents a promising strategy for exploring fascinating physics, independent of their dimensionality, thereby offering a "three-dimensional" control for the era of slidetronics. While monolayer of 1T-TaS2 is considered to be a Mott insulator, the nature of the bulk insulating state is debated. Here the authors introduce a ladder-type structures with fractional misalignment of adjacent layers, showing that it becomes a Mott insulator due to decoupling between the layers. [ABSTRACT FROM AUTHOR]

Phase transition during annealing in the two‐step sequential deposition has drawn intensive attention as its significance in fabricating superior perovskite films. However, previous works have not paid enough attention to the importance of the purified phase transition path in the crystallization process. Herein, different from the mixed paths in the conventional cognition, purified phase transition path for α‐FAPbI3 crystallization is achieved by introducing dimethylurea (DMU) into lead iodide (PbI2) precursor solution. The multifunctional molecule is found to design a penetrable porous PbI2 film and fundamentally regulate the perovskite crystallization by forming single phase transition path via the complete δ‐phase during annealing of perovskite. The role of DMU in purified transition path for α‐FAPbI3 crystallization is unraveled with in situ photoluminescence and grazing incidence wide‐angle x‐ray scattering (GIWAXS) investigation. The crystal quality of perovskite films is significantly improved, resulting in single crystal‐like film. The best‐performing perovskite solar cells (PSCs) deliver a power conversion efficiency of 24.75%, resulting from the higher FF of 83.25% and an improved long‐term stability up to 3600 h. This work highlights the importance of purified phase transition path for the superior crystal quality toward high‐performance perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Perovskite photovoltaics, typically based on a solution-processed perovskite layer with a film thickness of a few hundred nanometres, have emerged as a leading thin-film photovoltaic technology. Nevertheless, many critical issues pose challenges to its commercialization progress, including industrial compatibility, stability, scalability and reliability. A thicker perovskite film on a scale of micrometres could mitigate these issues. However, the efficiencies of thick-film perovskite cells lag behind those with nanometre film thickness. With the mechanism remaining elusive, the community has long been under the impression that the limiting factor lies in the short carrier lifetime as a result of defects. Here, by constructing a perovskite system with extraordinarily long carrier lifetime, we rule out the restrictions of carrier lifetime on the device performance. Through this, we unveil the critical role of the ignored lattice strain in thick films. Our results provide insights into the factors limiting the performance of thick-film perovskite devices. The power conversion efficiencies of thick-film perovskite solar cells lag behind those with nanometre film thickness. Here, the authors rule out the restrictions of carrier lifetime on device performance and reveal the critical role of lattice strain in micron-scale thick perovskite films. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional (quasi‐2D) perovskites are emerging as efficient emitters in blue perovskite light‐emitting diodes (PeLEDs), while the imbalanced crystallization of the halide‐mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non‐radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low‐dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+‐guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi‐2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure‐blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide‐mixed blue perovskite crystallization by manipulating the characteristics of grain‐growth substrate. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional (quasi‐2D) perovskites are emerging as efficient emitters in blue perovskite light‐emitting diodes (PeLEDs), while the imbalanced crystallization of the halide‐mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non‐radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low‐dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+‐guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi‐2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure‐blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide‐mixed blue perovskite crystallization by manipulating the characteristics of grain‐growth substrate. [ABSTRACT FROM AUTHOR]

The deviated crystallization kinetics of solution‐processed perovskite layers caused by the bottom interface is a barrier to comprehensively suppressing the defect formation and further to efficaciously improve the film quality and device performance. Herein, it is reported that the incorporation of a PEA2PbBr4 interlayer can effectively modify the crystallization process of the quasi‐2D mixed‐halide perovskite layers, resulting in enhanced Lewis acid‐base interaction and improved film homogeneity, which contributes to the strong defect passivation efficacy toward efficient sky‐blue emission. As a result, the devices with the bottom‐interface modification show a maximum external quantum efficiency of 14.2%, impressively an outstanding power efficiency of 17.0 lm W−1, and an external quantum efficiency of 12.3% at 1000 cd m−2. This work provides an insight into crystallization kinetics for defect suppression of the perovskite layer and further highlights the defect passivation efficacy of 2D perovskite‐based bottom‐interface modification toward high‐efficiency sky blue‐emitting diodes. [ABSTRACT FROM AUTHOR]

In scientific research, basic research that is both curiosity-driven and use-inspired is known as Pasteur's Quadrant. The research on the impact and attention of Pasteur's Quadrant is an essential research topic in academia. In view of the many milestone breakthroughs that Artificial Intelligence (AI) has brought to humanity, this paper delves into Pasteur's Quadrant in AI through the citation of papers by patents. We empirically analyse the scientific impact of 3322 patent-cited papers and 6587 non-patent-cited papers published from 1999 to 2013, where scientific impact is measured by scientific citations and usage counts. Our main results show that patent-cited papers have a stronger scientific impact than non-patent-cited papers, and this impact is further enhanced in conference publications than in journal publications. Further, the relationship between the multidimensional characteristics of patent citations and scientific impact is investigated in terms of patent-cited papers. We find an inverted U-shaped relationship between the intensity of a paper's patent citations and its scientific citations, as well as between the breadth of a paper's patent citations and its scientific citations. In addition, the patent citation lag of a paper negatively relates to its scientific impact. [ABSTRACT FROM AUTHOR]

Tin halide perovskite solar cells are promising for the next generation of highly efficient photovoltaics. Their commercialization can be accelerated by increasing their stability in moisture and oxygen. Herein, an n‐type organic molecule (IO‐4Cl) is applied as an interlayer between the perovskite films and electron transport layers in p‐i‐n structured devices. The electron‐rich indacenodithieno‐[3,2‐b]thiophene enhances electron transport, while the hydrocarbon side chains and rigid conjugated backbone isolate air. It is also shown that the C═O in IO‐4Cl can coordinate with Sn2+ on perovskite films' surface and grain boundaries to enhance perovskite crystal stability. In addition, IO‐4Cl slows down crystallization dynamics, resulting in lower non‐radiation recombination. The moisture ingress in the perovskite films is tracked under high relative humidity (RH) and it is found that IO‐4Cl can mitigate moisture infiltration. Finally, the devices with IO‐4Cl maintain 95% of the initial power conversion efficiency after 1200 h of storage in a nitrogen‐filled glovebox, and their stability in ambient air (60–80% RH) is significantly improved against pristine devices, thus demonstrating the beneficial effects of IO‐4Cl interlayer on device stability. [ABSTRACT FROM AUTHOR]

Based on ab initio molecular dynamics simulations, we determined the melting curve of magnesium (Mg) up to ∼460 GPa using the solid–liquid coexistence method. Between ∼30 and 100 GPa, our melting curve is noticeably lower than those from static experiments but is in good agreement with recent shock experiments. Up to ∼450 GPa, our melting curve is generally consistent with the melting points from first-principles calculations using the small-cell coexistence method. We found that, at high pressures of a few hundred GPa, due to the strong softening of interatomic interactions in the liquid phase, solid–liquid coexistence simulations of Mg show some characteristics distinctively different from other metal systems, such as aluminum. For example, at a given volume, the pressure and temperature range for maintaining a stable solid–liquid coexistence state can be very small. The strong softening in the liquid phase also causes the unusual behavior of reentrant melting to occur at very high pressures. The onset of reentrant melting is predicted at ∼305 GPa, close to that at ∼300 GPa from the small-cell coexistence method. We show that the calculated melting points, considering reentrant melting, can be excellently fitted to a low-order Kechin equation, thereby making it possible for us to obtain a first-principles melting curve of Mg at pressures above 50 GPa for the first time. Similar characteristics in solid–liquid coexistence simulations, as well as reentrant melting, are also expected for other systems with strong softening in the liquid phase at high pressures. [ABSTRACT FROM AUTHOR]

Perovskite solar cells with the formula FA1−xCsxPbI3, where FA is formamidinium, provide an attractive option for integrating high efficiency, durable stability and compatibility with scaled-up fabrication. Despite the incorporation of Cs cations, which could potentially enable a perfect perovskite lattice1,2, the compositional inhomogeneity caused by A-site cation segregation is likely to be detrimental to the photovoltaic performance of the solar cells3,4. Here we visualized the out-of-plane compositional inhomogeneity along the vertical direction across perovskite films and identified the underlying reasons for the inhomogeneity and its potential impact for devices. We devised a strategy using 1-(phenylsulfonyl)pyrrole to homogenize the distribution of cation composition in perovskite films. The resultant p–i–n devices yielded a certified steady-state photon-to-electron conversion efficiency of 25.2% and durable stability.We added out-of-plane cations to homogenize the distribution of cations in perovskite films, resulting in a solar cell with improved efficiency and stability. [ABSTRACT FROM AUTHOR]

Materials descriptors with multivariate, multiphase, and multiscale of a complex system have been treated as the remarkable materials genome, addressing the composition–processing–structure–property–performance (CPSPP) relationships during the development of advanced materials. With the aid of high‐performance computations, big data, and artificial intelligence technologies, it is still a challenge to derive an explainable machine learning (ML) model to reveal the underlying CPSPP relationship, especially, under the extreme conditions. This work supports a smart strategy to derive an explainable model of composition–property–performance relationships via a hybrid data‐driven and knowledge‐enabled model, and designing superhard high‐entropy diboride ceramics (HEBs) with a cost‐effective approach. Five dominate features and optimal model were screened out from 149 features and nine algorithms by ML and validated in first‐principles calculations. From Shapley additive explanations (SHAP) and electronic bottom layer, the predicted hardness increases with the improved mean electronegativity and electron work function (EWF) and decreases with growing average d valence electrons of composition. The 14 undeveloped potential superhard HEBs candidates via ML are further validated by first‐principles calculations. Moreover, this EWF‐ML model not only has better capability to distinguish the differences of solutes in same group of periodic table but is also a more effective method for material design than that of valence electron concentration. [ABSTRACT FROM AUTHOR]

Modifying the exposed upper surface of perovskite solar cells (PSCs) has greatly contributed to improving their photovoltaic performance. The equally important buried interface (that is, the hidden bottom of perovskite film and the beginning of perovskite film crystallization) is much less studied due to great difficulties in tailoring it. Here we expose the large-area buried interface non-destructively for direct investigation. We find that the disordered beginning of the perovskite film growth deteriorates the buried interface. To address this issue, instead of using a passivator, we synthesize a transparent and conductive oxide perovskite (SrSnO3) to act as the electron transport layer. The high lattice matching enables a more ordered beginning of the growth of halide perovskite on the electron transport layer, avoiding the formation of a deteriorated buried interface. The constructed buried interface exhibits suppressed defects, strain, better crystallinity, reduced ion migration and fewer voids. The best performing PSCs deliver a power conversion efficiency of 25.17%. Moreover, PSCs with an initial power conversion efficiency of 24.4% maintain 90% of the original value after operating for 1,000 h. Employing a lattice-matched perovskite oxide as an electron transport layer allows optimizing the buried interface in perovskite solar cells. A maximum power conversion efficiency of 25.17% is achieved. Cells with an initial power conversion efficiency of 24.4% maintain 90% efficiency after operation for 1,000 h. [ABSTRACT FROM AUTHOR]

An intelligent, vision-guided welding robot is highly desired in machinery manufacturing, the ship industry, and vehicle engineering. The performance of the system greatly depends on the effective identification of weld seam features and the three-dimensional (3D) reconstruction of the weld seam position in a complex industrial environment. In this paper, a 3D visual sensing system with a structured laser projector and CCD camera is developed to obtain the geometry information of fillet weld seams in robot welding. By accounting for the inclination characteristics of the laser stripe in fillet welding, a Gaussian-weighted PCA-based laser center line extraction method is proposed. Smoother laser centerlines can be obtained at large, inclined angles. Furthermore, an improved chord-to-point distance accumulation (CPDA) method with polygon approximation is proposed to identify the feature corner location in center line images. The proposed method is validated numerically with simulated piece-wise linear laser stripes and experimentally with automated robot welding. By comparing this method with the grayscale gravity method, Hessian-matrix-based method, and conventional CPDA method, the proposed improved CPDA method with PCA center extraction is shown to have high accuracy and robustness in noisy welding environments. The proposed method meets the need for vision-aided automated welding robots by achieving greater than 95% accuracy in corner feature point identification in fillet welding. [ABSTRACT FROM AUTHOR]

The arc sound signal is one of the most important aspects of information related to pattern identification regarding the penetration state of ship robotic GMAW; however, arc sound is inevitably affected by noise interference during the signal acquisition process. In this paper, an improved wavelet threshold denoising method is proposed to eliminate interference and purify the arc sound signal. The non-stationary random distribution characteristics of GMAW noise interference are also estimated by using the high-frequency detail coefficients in different domains after wavelet transformation, and a mode of measuring scale that is logarithmically negatively correlated with the wavelet decomposition scale is created to update the threshold. The gradient convergent threshold function is established using the natural logarithmic function structure and concave–convex gradient to enable the nonlinear adjustment of the asymptotic rate. Further, some property theorems related to the optimized threshold function are proposed and theoretically proven, and the effectiveness and adaptability of the improved method are verified via the denoising simulation of speech synthesis signals. The four traditional denoising methods and our improved version are applied in the pretreatment of the GMAW arc sound signal, respectively. Statistical analysis and short-time Fourier transform are used to extract eight-dimensional time and frequency domain feature parameters from the denoised signals with randomly time-varying characteristics, and the extracted joint feature parameters are used to establish a nonlinear mapping model of penetration state identification for ship robotic GMAW using the pattern classifiers of RBFNN, PNN and PSO-SVM. The simulation results yielded by visual penetration classification and the multi-dimensional evaluation index of the confusion matrix indicate that the improved denoising method proposed in this paper achieves a higher accuracy in the extraction of penetration state features and greater precision in the identification of pattern classification. [ABSTRACT FROM AUTHOR]

The development of perovskite light‐emitting diodes (PeLEDs) with both high efficiency and excellent stability remains challenging. Herein, a strong correlation between the lattice strain in perovskite films and the stability of resulting PeLEDs is revealed. Based on high‐efficiency PeLEDs, the device lifetime is optimized by rationally tailoring the lattice strain in perovskite films. A PeLED with a high peak external quantum efficiency of 18.2% and a long lifetime of 151 h (T70, under a current density of 20 mA cm−2) is realized with a minimized lattice strain in the perovskite film. In addition, an increase in the lattice strain is found during the long‐time device stability test, indicating that the degradation of the local perovskite lattice structure could be one of the degradation mechanisms for long‐term stable PeLEDs. [ABSTRACT FROM AUTHOR]

This study evaluated the association between prenatal depression and offspring autism‐related traits. The sample comprised 33 prenatal/pediatric cohorts participating in the Environmental influences on Child Health Outcomes program who contributed information on prenatal depression and autism‐related traits. Autism‐related traits were assessed continuously and at the diagnostic cut‐off using the Social Responsiveness Scale for children up to 12 years of age. Main analyses included 3994 parent–child pairs with prenatal depression diagnoses data; secondary analyses included 1730 parent–child pairs with depression severity data. After confounder adjustment, we observed an increase in autism‐related traits among children of individuals with prenatal depression compared to those without (adjusted β = 1.31 95% CI: 0.65, 1.98). Analyses stratified by child sex documented a similar significant association among boys (aβ = 1.34 95%CI: 0.36, 2.32) and girls (aβ = 1.26 95% CI: 0.37, 2.15). Prenatal depression was also associated with increased odds of moderate to severe autism‐related traits (adjusted odds ratio: 1.64, 95%CI: 1.09, 2.46), the screening threshold considered high risk of autism spectrum disorder (ASD) diagnosis. Findings highlight the importance of prenatal depression screening and preventive interventions for children of pregnant individuals with depression to support healthy development. Future research is needed to clarify whether these findings reflect overlap in genetic risk for depression and ASD‐related traits or another mechanism. Lay Summary: Prenatal depression was associated with an increase in autism‐related traits and increased risk of moderate‐to‐severe autism‐related traits, the screening threshold considered at high risk for an autism spectrum disorder (ASD) diagnosis. Findings highlight the importance of prenatal depression screening and preventive interventions for children of pregnant individuals with depression to support healthy development. Future research is needed to clarify whether these findings reflect overlap in genetic risk for depression and ASD‐related traits or another mechanism. [ABSTRACT FROM AUTHOR]

Multiple scattering theory (MST) is one of the most widely used methods in electronic structure calculations. It features a perfect separation between atomic configurations and site potentials and hence provides an efficient way to simulate defected and disordered systems. This work studies MST methods from a numerical point of view and shows convergence with respect to the truncation of the angular momentum summations, which is a fundamental approximation parameter for all MST methods. We provide both rigorous analysis and numerical experiments to illustrate the efficiency of MST methods within the angular momentum representations. [ABSTRACT FROM AUTHOR]

Metal halide perovskite materials have demonstrated significant potential in various optoelectronic applications, such as photovoltaics, light emitting diodes, photodetectors, and lasers. However, the stability issues of perovskite materials continue to impede their widespread use. Many studies have attempted to understand the complex degradation mechanism and dynamics of these materials. Among them, in situ and/or operando approaches have provided remarkable insights into the degradation process by enabling precise control of degradation parameters and real-time monitoring. In this review, we focus on these studies utilizing in situ and operando approaches and demonstrate how these techniques have contributed to reveal degradation details, including structural, compositional, morphological, and other changes. We explore why these two approaches are necessary in the study of perovskite degradation and how they can be achieved by upgrading the corresponding ex situ techniques. With recent stability improvements of halide perovskite using various methods (compositional engineering, surface engineering, and structural engineering), the degradation of halide perovskite materials is greatly retarded. However, these improvements may turn into new challenges during the investigation into the retarded degradation process. Therefore, we also highlight the importance of enhancing the sensitivity and probing range of current in situ and operando approaches to address this issue. Finally, we identify the challenges and future directions of in situ and operando approaches in the stability research of halide perovskites. We believe that the advancement of in situ and operando techniques will be crucial in supporting the journey toward enhanced perovskite stability. [ABSTRACT FROM AUTHOR]

A solid solution is one of the important ways to enhance the structural and functional performance of materials. In this work, we develop a structural modeling approach to solid solutions based on the similar atomic environment (SAE). We propose a similarity function associated with any type of atom cluster to describe quantitatively the configurational deviation from the desired solid-solution structure that is fully disordered or contains short-range order (SRO). In this manner, the structural modeling for solid solutions is transferred to a minimization problem in the configuration space. Moreover, we strive to enhance the practicality of this approach. The approach and implementation are demonstrated by cross validations with the special quasi-random structure method. We apply the SAE method to the typical quinary CoCrFeMnNi high-entropy alloy, continuous binary Ta–W alloy, and ternary CoCrNi medium-entropy alloy with SRO as prototypes. In combination with ab initio calculations, we investigate the structural properties and compare the calculation results with experiments. [ABSTRACT FROM AUTHOR]

In order to overcome the disadvantages of contact measurement, time-consuming in traditional radial circular runout measurement, a non-contact measurement method based on machine vision technology is proposed in this paper. Using the image template matching and sub-pixel edge extraction techniques, the fine edge information of measured region is obtained. The rand sample consistency (RANSAC) algorithm is performed to filter the noise of edge data. Then, the least squares method is used for the parallel line fitting of two edges of measured region, and the reference axis of the shaft is gotten. The distance of measured point to the reference axis is defined as the radius at this rotating position, and the radius fluctuation at different rotational positions is the radial circular runout. The proposed method also allows random rotation of the measured shaft during the measuring process, and the high-precision-assisted rotation equipment is not essential, which enhances the convenience of the measuring equipment. [ABSTRACT FROM AUTHOR]

Optically active spin defects in van der Waals materials are promising platforms for modern quantum technologies. Here we investigate the coherent dynamics of strongly interacting ensembles of negatively charged boron-vacancy ( V B − ) centers in hexagonal boron nitride (hBN) with varying defect density. By employing advanced dynamical decoupling sequences to selectively isolate different dephasing sources, we observe more than 5-fold improvement in the measured coherence times across all hBN samples. Crucially, we identify that the many-body interaction within the V B − ensemble plays a substantial role in the coherent dynamics, which is then used to directly estimate the concentration of V B − . We find that at high ion implantation dosage, only a small portion of the created boron vacancy defects are in the desired negatively charged state. Finally, we investigate the spin response of V B − to the local charged defects induced electric field signals, and estimate its ground state transverse electric field susceptibility. Our results provide new insights on the spin and charge properties of V B − , which are important for future use of defects in hBN as quantum sensors and simulators. The boron vacancy center in hBN has been intensively studied, but its characterizations have remained limited. Here the authors achieve a 5-fold enhancement of coherence time using dynamical decoupling, which enables the direct estimation of defect concentration and its electric field susceptibility. [ABSTRACT FROM AUTHOR]

Highlights: The (011) facet has excellent charge transport properties achieving closer alignment of energy levels. By exploiting the (011) facet a device (0.06 cm2) and a module (29 cm2) achieved power conversion efficiencies of 25.24% and 21.12%, respectively. Perovskite crystal facets greatly impact the performance and stability of their corresponding photovoltaic devices. Compared to the (001) facet, the (011) facet yields better photoelectric properties, including higher conductivity and enhanced charge carrier mobility. Thus, achieving (011) facet-exposed films is a promising way to improve device performance. However, the growth of (011) facets is energetically unfavorable in FAPbI3 perovskites due to the influence of methylammonium chloride additive. Here, 1-butyl-4-methylpyridinium chloride ([4MBP]Cl) was used to expose (011) facets. The [4MBP]+ cation selectively decreases the surface energy of the (011) facet enabling the growth of the (011) plane. The [4MBP]+ cation causes the perovskite nuclei to rotate by 45° such that (011) crystal facets stack along the out-of-plane direction. The (011) facet has excellent charge transport properties and can achieve better-matched energy level alignment. In addition, [4MBP]Cl increases the activation energy barrier for ion migration, suppressing decomposition of the perovskite. As a result, a small-size device (0.06 cm2) and a module (29.0 cm2) based on exposure of the (011) facet achieved power conversion efficiencies of 25.24% and 21.12%, respectively. [ABSTRACT FROM AUTHOR]

Image processing and feature information extraction based on the visual perception of the weld pool are considered essential components of intelligent welding quality monitoring of hull structure gas metal arc welding (GMAW). The unstable characteristics, such as large spatter, much smoke, and strong arc light during hull structure GMAW, lead to the blurring of image acquisition and the difficulty of contour extraction of the weld pool. The present study is aimed at addressing the practical issues from two perspectives, i.e., a spectrum-visual-sensing acquisition system and an image-processing and feature extraction algorithm. First of all, by analyzing the light energy distribution law and acquiring the optical parameters relevant to the cut-off composite dimming and near-infrared narrowband filtering, spectral sensing is employed in establishing models of arc light radiation to detect the strength of continuously distinctive spectral lines. Besides, an appropriate high-speed charge-coupled device (CCD) camera is selected to build a visual acquisition system, which can reduce the external interference of the arc light on the image acquisition of the weld pool. Afterwards, the implementation of an image-processing fusion model based on the spatial information fuzzy C-means (FCM) clustering analysis and Sobel edge detection operator accompanies the investigation of the geometric aspects of the weld pool image. In terms of clear segmentation of the interest region, the edge detection and accurate extraction of the target contour are successfully obtained. In the subsequent section, the Hough transform analysis is adopted to establish the geometric feature extraction model of the weld pool, with corner detection, conversion, and camera calibration as the core technology. Additionally, the left and right views of the image contour are calibrated to achieve the lossless conversion of corner pixels and physical coordinates. Finally, three other distinct image-processing methods are designed to compare the segmentation effect of the edge contour with the fusion model, and then, the extraction accuracy of the geometric features of the weld pool is verified. The interference of the arc light and smoke has been demonstrated to be substantially diminished, which is attributable to the visual-sensing system during image acquisition of the weld pool. The results of edge fusion of the weld pool image show that based on the GMAW using the FCM-Sobel fusion method, a superior extraction accuracy of geometric features characterized by smoothness, continuousness, no breakpoints, and less noise has fulfilled the engineering requirements. [ABSTRACT FROM AUTHOR]