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The in situ protonation and crystallization of pyridine-functionalized small molecules 1–3with enantiopure camphor sulfonic acid afford ionic organic crystals, which exhibit bright blue circularly polarized luminescence (CPL) with high emission quantum efficiencies (Φ: 79–91%) and luminescence dissymmetry factors in the 10–2order. These crystals are investigated by microscopy, absorption and emission spectral, and powder and single-crystal X-ray diffraction analyses. The chiral optical properties of these microcrystals are examined by circular dichroism and CPL studies. By tuning the substitution position of the pyridine groups, microcrystals with different morphologies and opposite CPL signals are achieved.

Orthogonal time frequency space (OTFS) systems perform excellently in high mobility communications, but face the challenge of channel estimation. To optimize the channel estimation performance, a compressed sensing-basis expansion model (CS-BEM) OTFS channel estimation approach is proposed in this letter. First, a compressed sensing channel estimation model in the delay-Doppler (DD) domain is derived. Further, a dense pilot insertion scheme in the DD domain is specially designed, which reduces the redundant protected pilot and fully extracts the correlation information among the pilots. In particular, a combined orthogonal matching pursuit (COMP) algorithm is proposed to improve the coefficient estimation accuracy of BEM, benefiting from the exploitation of the coefficient segmentation joint sparsity property. Simulation results show that the proposed CS-BEM OTFS channel estimation approach has lower BER and channel estimation normalized mean square error (NMSE).

Photoinduced intramolecular charge separation in a pyrene- and triarylamine-based donor–acceptor dyad was studied by polarization-dependent femtosecond time-resolved transient absorption (TA) spectroscopy in polar solvents. Photoexcitation forms an excited state with charge transfer (CT) character due to the intrinsic electronic coupling between the triarylamine and pyrene groups, resulting in ultrafast charge separation (CS) in polar solvents. TA measurements reveal a correlation between the rate of CS and solvation dynamics, which implies that solvation is involved in the CS reaction. In addition, polarization-dependent TA spectroscopy was devoted to tracking the ultrafast anisotropy evolution of the cationic absorption band, which is attributed to intramolecular torsional motion and is proposed to be coupled to diffusive orientational solvent modes. The results therefore reveal that the evolution of the CT state in the condensed phase is driven by solvation-coupled excited-state structural relaxation. In other words, intramolecular torsional motion is directly confirmed to be involved in the reaction coordinate of the CS reaction in a strongly coupled donor–acceptor dyad.

Based on the two-pass differential temperature rolling bonding method, the effects of prefabricated steel/aluminum composite panel temperature on interface characteristics and microstructure properties were investigated through experimental analysis and finite element simulations. When the temperature exceeds 400 °C, the effective preparation of the steel–aluminum transition joint can be achieved, and with the increase in temperature, the interface shear and pull-off strength of the steel–aluminum transition joint exhibits an initial decrease followed by an increase. Both the interface shear and pull-off fractures are in 1060 aluminum matrix. As the temperature increases, the size of the average grain in 1060 aluminum matrix increases and then decreases. When the temperature reaches 550 °C, the comprehensive performance of the prepared steel–aluminum transition joint is the best, with the interface shear strength of 77 MPa and the interface pull-off strength of 153 MPa, exceeding the bonding strength of the explosive compounding method. There are no pinholes, wrinkles, or cracks in the lateral bending matrix and the interface.

Terahertz (THz) computed tomography (THz CT) exhibits the potential to provide a wealth of data, surpassing that of THz tomographic imaging in applications such as detecting embedded defects, particularly defect evolution within a glass fiber-reinforced polymer. To realize high-resolution THz CT, a systematic approach guided by wave propagation simulation was employed. First, the front wave of the THz beam was fine-tuned to realize a beam diameter of <2 mm. To mitigate the strong refractive effect and minimize Fresnel reflection loss, a refractive-index-matching material was fabricated and utilized as a rounded enclosure for samples with sharp corners. To further improve the reconstruction resolution, a flat surface enclosure was applied to collect all incident beams at the detector. To realize comparable results to those of full-angle CT, a limited-angle CT approach was implemented, and the frequency range 0.1–3 THz was used in the image reconstruction study. The experimental and simulated images were used to validate the findings, and conductive and non-conductive defects measuring 200 µm were successfully visualized. Additionally, a custom-built user interface enabled us to visualize the field spatial distribution of the THz beam with respect to frequency.

Two dual fluorescent/phosphorescent tris-heteroleptic mononuclear Ru(ΙΙ) complexes (2and 3) were designed and applied in amyloid-β (Aβ) sensing. These complexes have a general formula of [Ru(phen)(dppz)(L)](PF6)2, where Lis (2-pyrazinyl)(2-pyridyl)(methyl)amine (H-L) with different substituents (−OMe for 2, −H for 3), phen is 1,10-phenanthroline, and dppz is dipyridophenazine, respectively. Compared with the previously reported ratiometric probe 1with a di(pyrid-2-yl)(methyl)amine ligand, complex 2can be employed for not only ratiometric emissive detection of Aβ aggregation but also ratiometric imaging detection of Aβ fibrils. In ratiometric emissive detection, as the incubation time of the Aβ sample (Aβ40and Aβ42) was prolonged, a new phosphorescence emission band appeared with gradual enhancement of the emission intensity, while the fluorescence emission was basically unchanged, which could be treated as an intrinsic internal reference signal. In comparison, a larger ratiometric photoluminescence enhancement (I640/I440) was observed for Aβ40aggregation with respect to Aβ42. In ratiometric imaging detection, the imaging signals obtained from the phosphorescence emission are much brighter than the fluorescence emission in both Aβ40and Aβ42fibrils. As indicated by molecular docking results, stronger interactions were found between complex 2with Aβ40fibrils, which included π/π, π/C–H, and π/H interactions between bidentate ligands dppz and phen with amino acid residues. Moreover, computational calculations were carried out to assist the interpretation of these experimental findings.

We report a new supramolecular porous crystal assembled from fused macrocycle-cage molecules. The molecule comprises a prismatic cage with three macrocycles radially attached. The molecules form a nanoporous crystal with one-dimensional (1D) nanochannels. The supramolecular porous crystal can take up lithium-ion electrolytes and achieve an ionic conductivity of up to 8.3 × 10–4S/cm. Structural analysis and density functional theory calculations reveal that efficient Li-ion electrolyte uptake, the presence of 1D nanochannels, and weak interactions between lithium ions and the crystal enable fast lithium-ion transport. Our findings demonstrate the potential of fused macrocycle-cage molecules as a new design motif for ion-conducting molecular crystals.

Covalent organic framework (COF) film with electrofluorochromic (EFC) and electrochromic (EC) properties has been synthesized by using triphenylamine-based monomers. The film exhibited a high maximum fluorescence contrast of 151 when subjected to a drive voltage of 0.75 V vs the Ag/AgCl electrode, causing the fluorescence to be quenched, which resulted in the EFC process’s “fluorescence off” state. The switching times for the fluorescence on and off states were 0.51 and 7.79 s, respectively. Over the same voltage range, the COF film also displayed EC properties, achieving a contrast of 50.23% and a coloration efficiency of 297.4 cm2C–1at 532 nm, with switching times of 18.6 s for coloration and 0.7 s for bleaching. Notably, the quenched fluorescence of the COF film could be restored by adding dopamine as a reductant. This phenomenon enabled the implementation of a NAND logic gate using the applied potential as a physical input and dopamine addition as a chemical input. This study demonstrates the successful development of COF films with bifunctional EFC and EC properties, showcasing their potential for use in constructing advanced optoelectronic devices.

The base-mediated allylic defluorinative functionalization of β-CF2H-1,3-enynes with nucleophiles is described, affording terminal monofluoroalkenes bearing an alkynyl group in synthetically useful yields and Z/Eselectivities. Importantly, the resultant Z/Emixture could be separated by flash chromatography in all cases; thus, stereoisomerically pure monofluoroenynes were obtained. Postsynthetic modifications of the synthesized monofluoroenynes were also accomplished to access diverse molecular structures. Computational studies disclosed the origin of the diastereoselectivity.

Cancer is a major cause of death worldwide and a serious threat to human health. Cisplatin, a widely used first-line chemotherapeutic agent for various solid tumors, is renowned for its efficacy but is limited by significant cytotoxicity. Cisplatin triggers pyroptosis in tumor cells by activating Gasdermin proteins, thereby enhancing its anticancer efficacy. However, this same mechanism can induce pyroptosis in normal cells, causing inflammation and toxicity in healthy tissues, such as nephrotoxicity and ototoxicity. The objective of this review is to identify the major molecular targets for optimizing the cisplatin treatment window by summarizing recent advances in the pyroptosis caused by cisplatin in different cancer types and normal tissues. Among them, gasdermin D and gasdermin E are the main molecular targets involved in cisplatin-induced pyroptosis, and GSDMB also has similar effects. Future research directions include exploring targeted drug delivery systems and target regulating GSDMs (gasdermin protein family) to selectively modulate pyroptosis, thereby maximizing cisplatin’s anticancer effects while minimizing its side effects. Therefore, this review provides a comprehensive overview of cisplatin-induced pyroptosis, offering new insights into therapeutic strategies in cancer treatment.

Major disruption poses a significant challenge to the safe operation of tokamaks, so disruption mitigation is a key problem to be solved in tokamak. Currently, the fundamental strategy of disruption mitigation involves actively injecting significant quantities of impurity gas or solids (such as neon, argon, deuterium, etc.) to generate sufficient radiation power for dissipating the plasma’s energy. The most commonly used disruption mitigation devices now are massive gas injection (MGI) and shattered pellet injection (SPI). However, The impurity injection rate is low, resulting in shallow deposits in the tokamak. Electromagnetic pellet injection (EMPI) is a relatively new generation of disruption mitigation system developed in J-TEXT Tokamak. The system is based on the electromagnetic rail run concept. It uses electromagnetic force to launch the armature with an impurity pellet. The EMPI has been tested several times and the speed of the pellet has broken through the speed of sound, far exceeding the launch speed of the traditional disruption mitigation system. This means impurity is deposited at a deeper location. However, the rail length of EMPI is too long and the rail ablation is serious, so it is a challenging problem to satisfy the tokamak installation space requirements. Therefore, based on the EMPI, an enhanced EMPI is designed, which increases the electromagnetic force by increasing the magnetic field intensity within the bore. This enables the rail length to be decreased to meet the specified condition. Building upon this foundation, various armature-rail coupling structures have been designed. These structures are subjected to COMSOL finite element simulation to determine which rail-armature interface exhibits minimal ablation, superior electrical contact, and maximal armature launch velocity. Subsequently, the optimal rail-armature coupling scheme is validated through an experimentation test.

The damage characteristics of different speed sections of Cu−Cr−Zr alloy rail after simulated launch were studied. The microstructure, morphologies and properties of samples were investigated by using XRD, XPS, EBSD, SEM, hardness test, electrochemical test and DSC techniques. It was found that deposition layers were formed on the surfaces of the simulated launch samples. The thickness and surface roughness of these deposition layers increased with increasing the heat effect, suggesting a launch speed dependent damage degree of the arc ablation. The hardness variation of samples is attributed to the effects of the deposition layer and deformation hardening. The surface deposition layer affects corrosion resistance and crystalline characteristics, leading to changes in subsequent service performances. Additionally, the surface texture and plastic deformation ability of the samples are related to the recrystallization degree and deformation grain amount.

The letter investigated the design of junction termination extension structures with uniformly and non-uniformly distributed multiple P-type SiC micro-islands in 4H-SiC based Schottky Barrier Diode (SBD). By adjusting the length (LP), spacing (SP), number of islands (NP), and trapezoidal tilt angle ( $\theta $ ) of the micro-islands, the reverse performance of the devices is effectively optimized. Merging simulation with experimental methodologies, the performance of the SBD devices with varying terminal structures was analyzed. Simulation results indicate that a uniform distribution of multiple P-type micro-islands, particularly with L $_{\text {P}} = 13~\mu $ m, S $_{\text {P}} = 3~\mu $ m, and N $_{\text {P}} =6$ , exhibits a more uniform electric field distribution under reverse voltage of 1200 V and a higher terminal efficiency (exceeding 90%), while also saving more than 19% of the terminal area if compared to the non-uniform multiple P-island configurations. Furthermore, by changing the $\theta $ , the reverse performance of SBD devices and terminal efficiency can be affected with $\theta = 12^{\circ }$ , producing the best outcome.

Transient receptor potential ankyrin 1 (TRPA1) is a nonselective calcium ion channel highly expressed in the primary sensory neurons, functioning as a polymodal sensor for exogenous and endogenous stimuli, and has been implicated in neuropathic pain and respiratory disease. Herein, we describe the optimization of potent, selective, and orally bioavailable TRPA1 small molecule antagonists with strong in vivotarget engagement in rodent models. Several lead molecules in preclinical single- and short-term repeat-dose toxicity studies exhibited profound prolongation of coagulation parameters. Based on a thorough investigative toxicology and clinical pathology analysis, anticoagulation effects in vivoare hypothesized to be manifested by a metabolite─generated by aldehyde oxidase (AO)─possessing a similar pharmacophore to known anticoagulants (i.e., coumarins, indandiones). Further optimization to block AO-mediated metabolism yielded compounds that ameliorated coagulation effects in vivo, resulting in the discovery and advancement of clinical candidate GDC-6599, currently in Phase II clinical trials for respiratory indications.

The gradient nanostructure is machined on the aluminum (Al) alloy by the two-dimensional ultrasonic surface burnishing process (2D-USBP). The mechanism of why the gradient nanostructure enhances wear resistance is investigated. The mechanical properties and microstructure characterization for the gradient nanostructure are performed by operating a nanoindenter, transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). Dry wear tests are performed on the samples before and after machining to evaluate the wear resistance and mechanisms. The effect of the gradient nanostructure on the wear resistance is explored by developing the crystal plasticity (CP) finite element and molecular dynamics (MD) models. The characterization results show that the 2D-USBP sample prepared a gradient structure of ∼600 µm thick on the aluminum surface, increasing the surface hardness from 1.13 to 1.71 GPa and reducing the elastic modulus from 78.84 to 70.14 GPa. The optimization of the surface microstructure and the increase of the mechanical properties effectively enhance the wear resistance of the sample, with 41.20%, 39.07%, and 54.58% of the wear scar areas for the 2D-USBP treated samples to the original samples under 5, 10, and 15 N loads, respectively. The gradient nanostructure hinders the slip of dislocations inside the sample during the wear process and reduces the size and scope of plastic deformation; meanwhile, the resistance to deformation, adhesion, and crack initiation and propagation of the sample surface is improved, resulting in enhanced wear resistance.

High-capacity storage technologies are needed to meet our ever-growing data demands1,2. However, data centres based on major storage technologies such as semiconductor flash devices and hard disk drives have high energy burdens, high operation costs and short lifespans2,3. Optical data storage (ODS) presents a promising solution for cost-effective long-term archival data storage. Nonetheless, ODS has been limited by its low capacity and the challenge of increasing its areal density4,5. Here, to address these issues, we increase the capacity of ODS to the petabit level by extending the planar recording architecture to three dimensions with hundreds of layers, meanwhile breaking the optical diffraction limit barrier of the recorded spots. We develop an optical recording medium based on a photoresist film doped with aggregation-induced emission dye, which can be optically stimulated by femtosecond laser beams. This film is highly transparent and uniform, and the aggregation-induced emission phenomenon provides the storage mechanism. It can also be inhibited by another deactivating beam, resulting in a recording spot with a super-resolution scale. This technology makes it possible to achieve exabit-level storage by stacking nanoscale disks into arrays, which is essential in big data centres with limited space.

Doubled haploid (DH) technology is an important tool in crop breeding because it can significantly accelerate the breeding process. ZmPLA1/MATL/NLDand ZmDMPare two key genes controlling haploid induction (HI) in maize, exhibiting a synergistic effect. However, it is unknown whether knock out of ZmDMP orthologs can stimulate HI in rice. In this study, a ZmPLA1ortholog (OsPLA1) and two ZmDMPorthologs (OsDMP3and OsDMP6) were identified in rice. All three genes encode plasma membrane-localized proteins and were highly expressed in mature anthers. Knockout of OsPLA1in both Minghui 63 and Nipponbare resulted in reduced seed setting rate (SSR) and caused HI. The osdmp3, osdmp6and the double mutant failed to trigger HI independently, nor increased the haploid induction rate (HIR) when combined with ospla1. Repeated pollinations operations of QX654A with the ospla1mutant significantly improve SSR, while reducing HIR. RNA-seq profiling of mature ospla1mutant anthers indicated that a large number of differentially expressed genes (DEGs) were enriched in redox homeostasis and lipid metabolic GO terms, plant hormone signal transduction, and MAPK signaling pathways. These findings provide important insights towards construction of an efficient DH breeding technology and study of the molecular mechanism of HI in rice.

An effective method was explored for the selective synthesis of sulfonamides and sulfenamides using sodium sulfinates and amines as starting materials. This method offers mild reaction conditions, a broad substrate scope, high efficiency, and readily accessible materials, making it suitable and an alternative strategy for the preparation of a variety of biologically or pharmaceutically active compounds.

Transformers are increasingly popular in computer vision, which treat an image as a sequence of image patches and learn robust global features from the sequence. However, pure transformers are not entirely suitable for hyperspectral and light detection and ranging (LiDAR) image classification because image classification requires both robust global features and discriminative local features. Therefore, this article introduces a novel convolution interaction transformer network (CITNet) for jointly classifying hyperspectral and LiDAR images. The process begins with a carefully designed multiscale asymmetric depthwise convolution (MADC) module that exploits the local–global correlations of shallow features. On this basis, a novel local–global transformer (LGTM) is equipped with a local–global feed-forward (LGF) network to extract in-depth local–global joint features from the multimodal data. Then, an optimization convolution cross-attention (OCA) module, incorporating a convolutional layer, is developed to simulate the spatial relationships of semantic tokens. Finally, extensive experiments are conducted on the well-known Trento (TR), Augsburg (AU), MUUFL (MU), and Houston2013 (HU) datasets. The overall accuracy (OA) reaches 99.76%, 97.40%, 91.06%, and 99.90%, respectively, which are 0.2%–1.66%, 0.32%–7.37%, 1.52%–12.71%, and 0.14%–93.79% higher than the state-of-the-art (SOTA) methods, demonstrating the effectiveness of CITNet in improving the joint classification accuracy of hyperspectral and LiDAR images.

Background: Wallace melon has a powerful, pleasant aroma when ripe. However, little is understood about the aroma profile and the Volatile Organic Compounds (VOCs) biosynthesis during ripening.Objective: The aim of this study is to investigate the metabolome and transcriptome of Wallace melon to study the mechanism underlying its aroma formation systematically.Methods: HS-SPME/GC-MS and RNA-Seq were used to analyze the VOCs and associated genes of Wallace melon from three developmental stages (i.e., green, transition, and yellow stages).Results: The aroma profiles included 47 VOCs, which were in connection with 35 genes. Yellow- stage fruits are more aromatic than the melons in the transition and green stages, producing higher concentrations of total VOCs (2994.36 ng/g), with ethyl acetate (543.16 ng/g) being the most abundant compound. Transcriptomic analysis revealed that the biosynthesis of VOCs was mainly related to fatty acid and amino acid metabolisms. Moreover, the lipoxygenase-1 (MELO3C014482.2), alcohol dehydrogenase-2 (MELO3C017100.2), 3-ketoacyl-CoA synthase-3 (MELO3C010941.2), and hydroperoxide dehydratase (MELO3C018412.2) genes were closely related to alcohols/esters through correlation analysis.Conclusion: The information generated will deepen the understanding of Wallace melon storage quality and guide melon product development.

The interference induced by doubly-selective channels does not follow a Gaussian distribution, which leads to an inaccurate prediction for the reliability of Pulse Amplitude Modulation-based Filter Bank Multi-Carrier (PAM-FBMC) systems. In this letter, we derive a closed-form expression for the Bit Error Probability (BEP) based on Complex Gaussian Ratio (CGR), which accurately predicts the Bit Error Rate (BER) of the system and provides a basis for system design. Specifically, we first investigate the distribution properties of the ratio between the received symbol and the channel coefficients (i.e., CGR) to derive its joint probability density function. Secondly, based on the joint probability density of the CGR, we derive its Cumulative Distribution Function (CDF). Finally, we calculate the marginal CDF and, in conjunction with the decision boundaries provided by the PAM constellation, derive the BEP. Simulation results show that the CGR-based BEP provides a better agreement with the simulated BER.

Marabú (Dichrostachys cinerea), a fast-growing shrub species, has garnered interest as a potential energy crop due to its properties. In developing thermochemical processes for utilising D. cinerea, specifically through pyrolysis, precise prediction of its behaviour is essential for optimising process efficiency and understanding the underlying mechanisms. This study focuses on comparing the effectiveness of kinetic and artificial neural network (ANN) modelling methods in predicting the pyrolysis of D. cinerea. Utilising thermogravimetric data at four different heating rates (5, 10, 20 and 40 °C/min), a kinetic model based on three independent parallel reactions was developed. In the ANN model, the input variables (heating rate (°C/min), temperature (°C) and time (min)) were used to predict the output variable: weight loss (%). To optimise a backpropagation neural network (BPNN), 4-fold cross-validation and Bayesian optimisation were employed. The findings demonstrate that both methods effectively predict weight loss, with the ANN model achieving superior accuracy in capturing experimental data, particularly at local maxima of weight loss, reflected by R2values exceeding 0.99. The ANN method excels without the need for predetermined kinetic reaction mechanisms, showcasing its ability to adapt to complex, non-linear types of behaviour more accurately than traditional models. This study not only provides valuable insights into the pyrolytic behaviour of D. cinereabut also establishes a benchmark for future research in the predictive modelling of pyrolysis for diverse types of lignocellulosic biomass.

High-entropy alloys (HEAs) have drawn significant attention within the materials science community due to their exceptional properties. However, optimizing compositions in these alloys is challenging due to their vast compositional space. Conventional computational methods are constrained by high computational costs, limiting rapid database expansion. In this study, we propose a novel approach that integrates first-principles calculations with machine learning to efficiently explore the Al-Co-Cr-Fe-Ni system, encompassing both face-centered cubic (FCC) and body-centered cubic (BCC) phases. Our approach establishes comprehensive relationships among compositions, phase stability, and elastic properties at 0 K. A comprehensive database and software for this system are developed. Analysis of this database reveals the presence of FCC and BCC phases under specific valence electron concentration (VEC) criteria. Through screening and statistical analysis using a performance index, we quantitatively investigate the brittleness and ductility, facilitating the identification of optimal HEAs candidates. This work enhances our understanding of the HEA properties, offering a promising pathway for materials design and optimization.

Recombinant human type 5 adenovirus (H101) is an oncolytic virus used to treat nasopharyngeal carcinoma. Owing to the deletion of the E1B-55kD and E3 regions, H101 is believed to selectively inhibit nasopharyngeal carcinoma. Whether H101 inhibits other type of tumors via different mechanisms remains unclear. In this study we investigated the effects of H101 on melanomas. We established B16F10 melanoma xenograft mouse model, and treated the mice with H101 (1 × 108TCID50) via intratumoral injection for five consecutive days. We found that H101 treatment significantly inhibited B16F10 melanoma growth in the mice. H101 treatment significantly increased the infiltration of CD8+T cells and reduced the proportion of M2-type macrophages. We demonstrated that H101 exhibited low cytotoxicity against B16F10 cells, but the endothelial cells were more sensitive to H101 treatment. H101 induced endothelial cell pyroptosis in a caspase-1/GSDMD-dependent manner. Furthermore, we showed that the combination of H101 with the immune checkpoint inhibitor PD-L1 antibody (10 mg/kg, i.p., every three days for three times) exerted synergic suppression on B16F10 tumor growth in the mice. This study demonstrates that, in addition to oncolysis, H101 inhibits melanoma growth by promoting anti-tumor immunity and inducing pyroptosis of vascular endothelial cells.

Deep-ultradeep tight sandstone gas reservoirs are extremely important promising future energy. Natural fractures can improve the permeability and impact the overall reservoir quality. With the Dabei 9 Block of Kuqa Depression as an example, this study investigated and predicted the development and distribution of natural fractures in the tight sandstone reservoir based on R/Sanalysis method. Tensile-shear fractures are dominant fracture type within the block. Natural fractures primarily strike NW-SE and NE-SW directions with relatively high dip angle. Nearly 50% fractures are unfilled and partly filled. The coefficient index of fracture development Qwas defined and calculated according to the lg(R/S) function. Error analysis of fracture prediction was also carried out. The results show that the Qcorresponds to fracture density, and higher Qvalue commonly indicates larger density. Errors between fracture predictions and measures can be caused by various factors including fracture occurrence, fracture filling, limitation of conventional logging range, and multiple interpretations of logging curves. This study is expected to provide geological references for tight sandstone gas exploration and development in the Dabei 9 Block of Kuqa Depression. [Received: September 5, 2022; Accepted: August 19, 2023]

The surge current capability is one of the key parameters for the application of silicon carbide (SiC) Schottky barrier diode (SBD) in power converters. In this study, the surge current failure mechanism of a 650 V 4H-SiC SBD during non-repetitive surge current test is investigated. The ${I}-{V}$ measurements and microscopic observations before and after surge current failure demonstrate there are two types of failure mechanisms. Experimental and electro-thermal simulation results are combined to prove that the two different failure mechanisms originate from the varied thermal strain within the chip. This article presents the cause of surge current failure of SiC SBD and establishes a surge current failure model, which is applicable to predict and optimize the surge current capability of SiC SBD.

This paper describes a computational and experimental approach to electrodeposition of silicon using a MgF2-CaF2-CaO-Y2O3-SiO2molten salt electrolyte and a yttria-stabilized zirconia solid oxide membrane at the anode. A secondary and tertiary current density distribution model shows anodic current density between 0.5 and 1 A cm−2with a fairly even distribution along the anode surface except at the ends of the anodes. Finite element analysis of industrial cell magnetohydrodynamics (MHD) shows electrolyte flow to be 23 times slower compared to a calculated analytical model. The experiments demonstrate formation of highly pure silicon in the melt with particle sizes ranging from a few μm to clusters of 2 ~ 3 mm. Finally, the mechanism of Si formation based on a short thermodynamic analysis was discussed.

Organic–inorganic hybrid perovskites (OIHPs) have emerged as a prominent class of materials due to their diverse structures and tremendous potential in optics and electronics. Herein, we present two one-dimensional (1D) OIHPs, (C22H18N2)(PbX3)2(X = Cl or Br), in the form of single crystals and microcrystals that incorporate a bisprotonated bipyridinium compound as the organic cationic component. These two OIHPs possess a double-perovskite 1D chain structure, where the organic bipyridinium cations are linked to the perovskite octahedra through N–H···X hydrogen bonds. The chloride OIHP displays two emission bands that are attributed to the singlet free exciton of the organic moiety and the singlet self-trapped exciton (STE) of the perovskites, respectively. In contrast, the bromide analogue exhibits a single broad emission band originating from the triplet STE of the perovskites. Excitation wavelength and temperature-dependent photoluminescence studies provide insights into the distinct emission mechanisms of these two Pb-based OIHP materials.

Orthogonal Time Frequency Space (OTFS) modulation shows strong robustness in non-geostationary orbit (NGSO) satellite communications but is seriously impacted by narrowband interference (NBI). Thus, the energy concentration NBI suppression (ECNBIS) algorithm is proposed to remove the NBI. Particularly, translation matrices are first designed to concentrate the NBI energy by canceling out the phase shifts. Peak determination and cyclic zero setting are then used for interference detection and removal. Finally, the interference suppression framework is established with the Harris Hawk Optimization (HHO) algorithm. Simulation results show that the proposed algorithm requires a signal-to-noise ratio (SNR) reduction of more than 1 dB.

Learning representations with self-supervision for convolutional networks (CNN) has been validated to be effective for vision tasks. As an alternative to CNN, vision transformers (ViT) have strong representation ability with spatial self-attention and channel-level feedforward networks. Recent works reveal that self-supervised learning helps unleash the great potential of ViT. Still, most works follow self-supervised strategies designed for CNN, e.g., instance-level discrimination of samples, but they ignore the properties of ViT. We observe that relational modeling on spatial and channel dimensions distinguishes ViT from other networks. To enforce this property, we explore the feature SElf-RElation (SERE) for training self-supervised ViT. Specifically, instead of conducting self-supervised learning solely on feature embeddings from multiple views, we utilize the feature self-relations, i.e., spatial/channel self-relations, for self-supervised learning. Self-relation based learning further enhances the relation modeling ability of ViT, resulting in stronger representations that stably improve performance on multiple downstream tasks.

Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid areas. However, the presence of residual film in farmland soil has also drawn much attention. In this study, three experiments were conducted. The first two experimental designs included 0, 450, 1 350, and 2 700 kg ha−1of residual film pieces of approximately 5 cm side length added to field soil (0–20 cm soil depth) for seven years and added to pots for four years. In the third experiment, 1 350 kg ha−1of the residual film with different side lengths (2–5, 5–10, 10–15, and 15–20 cm) was added to field soil for six years to explore the effect of residual film fragment size on soil nutrients, soil microorganisms, crop growth and yields. The residual film had little effect on the soil moisture at a field depth of 0–2 (or 0–1.8) m. There were no significant effects on organic carbon, total nitrogen, inorganic nitrogen, total phosphorus or available phosphorus in the 0–20 cm soil layer. The presence of residual film decreased the richness and diversity of the bacterial community of the surface soil of the residual film, but it had no significant effect on the microbial community of the non-surface soil. The emergence rates of wheat and lentils occasionally decreased significantly with different amounts of residue fragments added to the field. At 450–2 700 kg ha−1, the residual film reduced the plant height and stem diameter of maize and significantly reduced the shoot biomass of harvested maize by 11–19%. The average yields of maize and potato over the seven years decreased, but there were almost no significant statistical differences among the treatments. These results provide important data for a comprehensive scientific understanding of the effects of residual film on soil and crops in dryland farming systems.

Background (BG) tasks are maintained indispensably in multiple layers of storage systems, from applications to flash-based SSDs. They launch a large amount of I/Os, causing significant interference with foreground (FG) I/O performance. Our key insight is that, to mitigate such interference, holistic scheduling of system-wide, multi-source BG I/Os is required and can only be realized at the underlying SSD layer. Only the SSD has a global view of all FG and BG I/Os as well as direct information and control about flash storage resources. We are thus inspired to propose a novel I/O scheduling architecture, called HuFu. It provides a framework for host software to register BG tasks and offload their I/O scheduling into the SSD. Then, the SSD-internal I/O scheduler prioritizes FG I/O processing, while BG I/Os are scheduled opportunistically by utilizing flash parallelism and idleness. To verify HuFu, we perform case studies on RocksDB and compares it with several state-of-the-art host-side I/O scheduling schemes. Experimental results show that HuFu can significantly alleviate performance interference caused by BG I/Os and improve SSD bandwidth utilization, thus improving the FG throughput, average and tail latencies (e.g., by about 18% in a write-heavy workload).

Materials with efficient circularly polarized phosphorescences (CPPs) are of potential use in advanced data encryption and anti-counterfeiting, bioimaging, optoelectronic devices and so forth. Herein, a simple method is presented for the preparations of CPP-active micro/nanocrystals with large luminescence dissymmetry factors (glum), high phosphorescence quantum efficiencies (Φp) and tunable emission colors. Diastereomeric IrIIIand RuIIcomplexes with chiral (±)-camphorsulfonate counter-anions are readily synthesized and assembled into crystalline microrods, microplates or nanofibers with ordered morphologies. The chir-ality information of chiral counter-anions is efficiently transferred to the metal components to afford CPPs with cyan, green, yellow, or red emission colors and ΦPin the range of 5%–85%. The number of chiral anions is found to play a role in influencing the CPP magnitudes of these crystals. The dicationic RuIIand tricationic IrIIIcomplexes show glumvalues in the 10−2order, which are much larger with respect to those of monocationic IrIIIcomplexes. Single crystal X-ray analysis is performed to obtain information on the chirality transfer of these materials. In addition, circularly polarized photonic signal waveguiding is demonstrated using the microcrystals of an IrIIIcomplex. This work demonstrates an appealing strategy of constructing chiral micro/nano-architectures for potential applications in chiral nanophotonics.

The initial pitting corrosion behavior triggered by inclusions in S420 low alloy steel in acidic artificial seawater (ASW) and weak-alkaline ASW was characterized. The geometric data of the corrosion pits formed in the ASW with different pH were calculated. The pH of the ASW has an obvious influence on the pit shape. The pits in acidic ASW exhibit a funnel shape, while those in weak-alkaline ASW present a cone shape with a larger pit volume. The reason for the difference in the morphology and size of the corrosion pits induced by inclusion is that it is easier to trigger micro-galvanic corrosion in different structures and different areas of the pits in the acidic environment.

In recent years, the potential of photocatalysis for environmental purification and energy conversion has been gradually explored. However, the limited light absorption and easy recombination ability of photogenerated carriers limit its development. To promote the photocatalytic reaction, the surface modification of photocatalytic materials is usually performed to enhance the photocatalytic activity. This review first presents the recent research progress of surface engineering strategies in photocatalytic oxidation of elemental mercury. Then the mechanism of surface engineering strategies to promote photocatalytic oxidation of Hg0reaction is analyzed at the level of energy band structure, carrier separation, and molecular activation. Next, the application of surface engineering strategies in photocatalysis is described, including environmental purification and energy conversion. Finally, future opportunities and challenges for the development of photocatalysis are presented. This review can not only provide scientific and theoretical guidance for the modification design of photocatalytic materials but also provide strong support for the preparation of photocatalysts for energy conversion and environmental remediation.