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Diamond is considered the most promising next-generation semiconductor material due to its excellent physical characteristics. It has been more than three decades since the discovery of a special structure named n-diamond. However, despite extensive efforts, its crystallographic structure and properties are still unclear. Here, we show that subdisordered structures in diamond provide an explanation for the structural feature of n-diamond. Monocrystalline diamond with subdisordered structures is synthesized via the chemical vapor deposition method. Atomic-resolution scanning transmission electron microscopy characterizations combined with the picometer-precision peak finder technology and diffraction simulations reveal that picometer-scale shifts of atoms within cells of diamond govern the subdisordered structures. First-principles calculations indicate that the bandgap of diamond decreases rapidly with increasing shifting distance, in accordance with experimental results. These findings clarify the crystallographic structure and electronic properties of n-diamond and provide new insights into the bandgap adjustment in diamond.

In hydrocarbon exploration, seismic data collected in the field inevitably encounter noise interference, which subsequently affects the data processing and interpretation. Recently, deep learning methods have gained widespread popularity in seismic denoising. Among these methods, the U-Net has shown some potential, but its performance in complex noise suppression needs further improvement due to the limitations of the U-Net structure. Moreover, the majority of existing noise suppression methods primarily focus on synthetic noises with single characteristics, such as Gaussian random noise and linear interference. To devise methods that can effectively suppress more intricate field noise, this article proposes a novel noise suppression method based on an encoder–decoder architecture called multiscale channel attention Swin Conv U-Net. Notably, it enhances the U-Net through the integration of the following two modules: 1) Swin-Conv block (SCB), which replaces the convolution operation of U-Net and integrates the nonlocal modeling ability of Swin Transformer (SwinT) and the local modeling ability of residual connection convolution layers to achieve multidimensional feature extraction, and 2) multiscale channel attention block (MCAB), which replaces skip connection modules between the encoder and the decoder in the U-Net with multichannel feature fusion to capture more complex channel dependencies. This article evaluates the proposed algorithm on both synthetic and field seismic data and compares the results with several established denoising methods. Our algorithm enhances the network’s noise perception capabilities and improves signal-to-noise ratio (SNR) and structural similarity index measure (SSIM) of seismic data. Finally, a concise discussion on the limitations of our method and potential avenues for enhancement is provided.

NOxstorage–reduction (NSR), a promising approach for removing NOxpollutants from diesel vehicles, remains elusive to cope with the increasingly lower exhaust temperatures (especially below 250 °C). Here, we develop a conceptual electrified NSR strategy, where electricity with a low input power (0.5–4 W) is applied to conductive Pt and K co-supported antimony-doped tin oxides (Pt–K/ATO), with C3H6as a reductant. The ignition temperature for 10% NOxconversion is nearly 100 °C lower than that of the traditional thermal counterpart. Furthermore, reducing the power in the fuel-lean period relative to that in the fuel-rich period increases the maximum energy efficiency by 23%. Electrically driven release of lattice oxygen is revealed to play vital roles in multiple steps in NSR, including NO adsorption, desorption, and reduction, for improved NSR activity. This work provides an electrification strategy for developing high-activity NSR catalysis utilizing electricity onboard hybrid vehicles.

The instabilities of oxygen redox lead to a large number of oxygen defects, which in turn exposes more interface contacting with the electrolyte and promotes the electrochemical activation of Li-rich oxides.

Inversion domains (IDs) are common defects in N-polar III-nitride thin films grown on sapphire substrates. In this work, the atomic structure and lateral migration of the randomly distributed Al-polar nanoscale IDs in N-polar AlN films subjected to high-temperature thermal annealing are investigated. With the increasing annealing temperature and time, Al-polar AlN IDs gradually shrunk in sizes. The vertical stripes transformed into cone-shaped caps on top of the AlN columns and were completely removed at last. The annihilation of the IDs was explained in terms of the lateral migration of the inversion domain boundary (IDB) induced by the imbalance of the strain state on two sides of the IDB. This work clarifies the evolution mechanism of AlN IDs during high-temperature annealing, providing a promising approach in the realization of uniform-polar AlN template for the development of high-efficiency optoelectronic and electronic devices.

Finding water resources is a crucial objective of lunar missions. However, both hydroxyl (OH) and natural water (H2O) have been reported to be scarce on the Moon. We propose a potential method for obtaining water on the Moon through H2O formation via endogenous reactions in lunar regolith (LR), specifically through the reaction FeO/Fe2O3 + H → Fe + H2O. This process is demonstrated using LR samples brought back by the Chang’E-5 mission. FeO and Fe2O3are lunar minerals containing Fe oxides. Hydrogen (H) retained in lunar minerals from the solar wind can be used to produce water. The results of this study reveal that 51–76 mg of H2O can be generated from 1 g of LR after melting at temperatures above 1,200 K. This amount is ∼10,000 times the naturally occurring OH and H2O on the Moon. Among the five primary minerals in LR returned by the Chang’E-5 mission, FeTiO3ilmenite contains the highest amount of H, owing to its unique lattice structure with sub-nanometer tunnels. For the first time, in situheating experiments using a transmission electron microscope reveal the concurrent formation of Fe crystals and H2O bubbles. Electron irradiation promotes the endogenous redox reaction, which is helpful for understanding the distribution of OH on the Moon. Our findings suggest that the hydrogen retained in LR is a significant resource for obtaining H2O on the Moon, which is helpful for establishing a scientific research station on the Moon.

The microstructure of twinning as well as the phase boundary between 1:5H and 2:17R phase in Fe-rich Sm2Co17-type magnets was characterized at atomic scale using nanobeam diffraction and high-resolution STEM-HAADF imaging, and the reason for the dramatic increase of coercivity during slow cooling was investigated based on the microchemistry analysis. The twinning relationship in the 2:17R phase originates from ordered substitution of Sm atoms by Co–Co atomic pairs on every three (3¯033) and (303¯3) planes, leading to formation of two corresponding equivalent twin variants. The basal plane of the 2:17R phase, the 1:3R platelet phase across the 2:17R cell and the 1:5H cell boundary phase between two adjacent 2:17R cells all can act as effective twin boundary. The cell boundary phase is precipitated along the pyramidal habit plane, and a fully coherent phase boundary (PB) is formed between the 1:5H and 2:17R phases with the orientation relationship to be PB//(112¯1)1:5H//(101¯1)2:17R. The phase boundary may either be parallel to or intersect with the pyramidal planes occupied by Co–Co atomic pairs. The substantial increase of coercivity during slow cooling is ascribed to the development of large gradient of the elements concentration within the cell boundary phase, resulting in large gradient of domain wall energy, and thus the pinning strength of the cell boundary phase against magnetic domain wall motion is significantly enhanced.

Although transition-metal nitrides have been widely applied for several decades, experimental investigations of their high-resolution electronic band structures are rare due to the lack of high-quality single-crystalline samples. Here, we report on the first momentum-resolved electronic band structures of titanium nitride (TiN) films, which are remarkable nitride superconductors. The measurements of the crystal structures and electrical transport properties confirmed the high quality of these films. More importantly, from a combination of high-resolution angle-resolved photoelectron spectroscopy and first-principles calculations, the extracted Coulomb interaction strength of TiN films can be as large as 8.5 eV, whereas resonant photoemission spectroscopy yields a value of 6.26 eV. These large values of Coulomb interaction strength indicate that superconducting TiN is a strongly correlated system. Our results uncover the unexpected electronic correlations in transition-metal nitrides, potentially providing a perspective not only to understand their emergent quantum states but also to develop their applications in quantum devices.

The real time analysis structure evolution of BNNT with compression showed that the formation of V-shape in the post-buckling before BNNT fracture was reversible.

The nanocrystal-in-glass (nanocrystals embedded amorphous matrix) tungsten oxide (WO3) thin films with a nanoporous characteristic were prepared via an electron beam evaporation technique. The e-beam evaporated WO3thin films present a fast colored/bleached time of 16/11, 16/14, and 12/12 s, a large optical modulation of 92, 91, and 87% at 633 nm, and a high coloration efficiency of 61.78, 62.04, and 67.59 cm2C–1in Li+, Na+, and Al3+electrolytes, respectively. On one hand, the improved electrochromic performance is mainly attributed to the short diffusion distance and buffering effect in the host matrix, which facilitates the ion insertion/extraction and alleviates the structural collapse of the framework. On the other, owing to the strong electrostatic interactions between the trivalent cations and the host, the WO3thin films in Al3+possess a shallow diffusion depth and long cycle life. The individual contribution from the capacitance- or diffusion-controlled process is comprehensively demonstrated. Pseudocapacitive behavior in the nanocrystal-in-glass WO3thin films is in favor of fast kinetics response and sound cycling stability. Our work offers an in-depth insight of the electrochromic mechanism for nanocrystal-in-glass WO3thin films in various electrolytes and sheds light on the fundamental principle in the electrochromic devices.

Nanostructures in silicon (Si) induced by phase transformations have been investigated during the past 50 years. Performances of nanostructures are improved compared to that of bulk counterparts. Nevertheless, the confinement and loading conditions are insufficient to machine and fabricate high-performance devices. As a consequence, nanostructures fabricated by nanoscale deformation at loading speeds of m/s have not been demonstrated yet. In this study, grinding or scratching at a speed of 40.2 m/s was performed on a custom-made setup by an especially designed diamond tip (calculated stress under the diamond tip in the order of 5.11 GPa). This leads to a novel approach for the fabrication of nanostructures by nanoscale deformation at loading speeds of m/s. A new deformation-induced nanostructure was observed by transmission electron microscopy (TEM), consisting of an amorphous phase, a new tetragonal phase, slip bands, twinning superlattices, and a single crystal. The formation mechanism of the new phase was elucidated by ab initio simulations at shear stress of about 2.16 GPa. This approach opens a new route for the fabrication of nanostructures by nanoscale deformation at speeds of m/s. Our findings provide new insights for potential applications in transistors, integrated circuits, diodes, solar cells, and energy storage systems.

Nanotwinned (nt) materials exhibit excellent mechanical properties, and have been attracting much more attention of late. Nevertheless, the fundamental mechanism of interaction between dislocations and a single nanotwin is not understood. In this study, in situ transmission electron microscopy (TEM) nanoindentation is performed, on a specimen of a nickel (Ni) alloy containing a single nanotwin of 89 nm in thickness. The specimen is prepared using focused ion beam (FIB) technique from an nt surface, which is formed by a novel approach under indentation using a developed diamond panel with tips array. The stiffness of the specimen is ten times that of the pristine counterparts during loading. The ultrahigh stiffness is attributed to the generation of nanotwins and the impediment of the single twin to the dislocations. Two peak loads are induced by the activation of a new slip system and the penetration of dislocations over the single nanotwin, respectively. One slip band is parallel to the single nanotwin, indicating the slip of dislocations along the nanotwin. In situ TEM observation of nanoindentation reveals a new insight for the interaction between dislocations and a single nanotwin. This paves the way for design and preparation of high-performance nt surfaces of Ni alloys used for aircraft engines, gas turbines, turbocharger components, ducts, and absorbers.

A new facile scalable method has been developed to synthesize silicon oxycarbide (SiOC)/carbon nanohybrids using difunctional dental methacrylate monomers as solvent and carbon source and the silane coupling agent as the precursor for SiOC. The content (from 100% to 40% by mass) and structure (ratio of disordered carbon over ordered carbon) of the free carbon matrix have been systematically tuned by varying the mass ratio of methacryloxypropyltrimethoxysilane (MPTMS) over the total mass of the resin monomers from 0.0 to 6.0. Compared to the bare carbon anode, the introduction of MPTMS significantly improves the electrochemical performance as a lithium-ion battery anode. The initial and cycled discharge/charge capacities of the SiOC/C nanohybrid anodes reach maximum with the MPTMS ratio of 0.50, which displays very good rate performance as well. Detailed structures and electrochemical performance as lithium-ion battery anodes have been systematically investigated. The structure–property correlation and corresponding mechanism have been discussed.

A facile route to synthesize Cu7S4hollow hexagonal-like nanoparticles using Cu2O nanocubes as sacrificial templates at room temperature was developed. According to the transmission electron microscopy and field emission scanning electron microscopy observations, a formation mechanism of the Cu7S4hollow structure based on the Kirkendall effect between the Cu7S4shell and Cu2O core at nanoscale was proposed. Interestingly, no conventional mass transport bridges between shell and core were observed, implying that a novel solution-mediated mass transportation dominates the Kirkendall process. The Cu2Se mesoboxs, with cubic morphology of the Cu2O templates preserved, were also fabricated by a similar route, which suggests that such synthesizing method might be readily extended to fabricate hollow structures of other metal chalcogenides.

Insect cuticle is a fiber-reinforced composite material that consists of polysaccharide chitin fibers and a protein matrix. The molecular interactions between insect cuticle proteins and chitin that govern the assembly and evolution of cuticles are still not well understood. Herein, we report that Ostrinia furnacaliscuticular protein hypothetical-1 (OfCPH-1), a newly discovered and most abundant cuticular protein from Asian corn borer O. furnacalis, can form coacervates in the presence of chitosan. The OfCPH-1–chitosan coacervate microdroplets are initially liquid-like but become gel-like with increasing time or salt concentration. The liquid-to-gel transition is driven by hydrogen-bonding interactions, during which an induced β-sheet structure of OfCPH-1 is observed. Given the abundance of OfCPH-1 in the cuticle of O. furnacalis, this liquid–liquid phase separation process and its aging behavior could play critical roles in the formation of the cuticle.

Background: Drought threatens the food supply of the world population. Dissecting the dynamic responses of plants to drought will be beneficial for breeding drought-tolerant crops, as the genetic controls of these responses remain largely unknown. Results: Here we develop a high-throughput multiple optical phenotyping system to noninvasively phenotype 368 maize genotypes with or without drought stress over a course of 98 days, and collected multiple optical images, including color camera scanning, hyperspectral imaging, and X-ray computed tomography images. We develop high-throughput analysis pipelines to extract image-based traits (i-traits). Of these i-traits, 10,080 were effective and heritable indicators of maize external and internal drought responses. An i-trait-based genome-wide association study reveals 4322 significant locus-trait associations, representing 1529 quantitative trait loci (QTLs) and 2318 candidate genes, many that co-localize with previously reported maize drought responsive QTLs. Expression QTL (eQTL) analysis uncovers many local and distant regulatory variants that control the expression of the candidate genes. We use genetic mutation analysis to validate two new genes, ZmcPGM2and ZmFAB1A, which regulate i-traits and drought tolerance. Moreover, the value of the candidate genes as drought-tolerant genetic markers is revealed by genome selection analysis, and 15 i-traits are identified as potential markers for maize drought tolerance breeding. Conclusion: Our study demonstrates that combining high-throughput multiple optical phenotyping and GWAS is a novel and effective approach to dissect the genetic architecture of complex traits and clone drought-tolerance associated genes.

Although nickel oxide (NiO) is currently the most promising for industrialization as a counter electrode, it has proven challenging to achieve long-term-stable electrochromic devices. One of the crucial components is the mechanism of action of water on the active interface of the NiO counter electrode in the Li+-based electrolyte, which gives a basis of determinants for improving long-term cycling stability in devices. Herein, we investigate the role of water on the electrochemical and electrochromic properties of nickel oxide (NiO) electrodes. The finding of improved pseudocapacitive characteristics and reaction kinetics of NiO electrodes after introducing H2O into the Li+-based electrolyte can be originated from the increase of the number of ions and reduction of the electrolyte resistance and the interfacial charge-transfer resistance. On the one hand, the mechanisms for improved electrochemical and electrochromic properties such as a high coloration efficiency of 157.58 cm2C−1under the potential window of ±1.4 V, an excellent rate capability and a superior long-term cycling stability of over 10,000 cycles in the ESCs based on WO3and NiO electrodes are elaborated. On the other hand, electrical water splitting can give rises to a degradation of optically cyclic stability of the NiO-based ESCs under the potential of > +1.23 V. These results provide a significant contribution to the reversibility and stability of the active interfaces for high performance electrochromic devices.