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Abstract The electronic orders in kagome materials have emerged as a fertile platform for studying exotic quantum states, and their intertwining with the unique kagome lattice geometry remains elusive. While various unconventional charge orders with broken symmetry is observed, the influence of kagome symmetry on magnetic order has so far not been directly observed. Here, using a high‐resolution magnetic force microscopy, it is, for the first time, observed a new lattice form of noncollinear spin textures in the kagome ferromagnet in zero magnetic field. Under the influence of the sixfold rotational symmetry of the kagome lattice, the spin textures are hexagonal in shape and can further form a honeycomb lattice structure. Subsequent thermal cycling measurements reveal that these spin textures transform into a non‐uniform in‐plane ferromagnetic ground state at low temperatures and can fully rebuild at elevated temperatures, showing a strong second‐order phase transition feature. Moreover, some out‐of‐plane magnetic moments persist at low temperatures, supporting the Kane–Mele scenario in explaining the emergence of the Dirac gap. The observations establish that the electronic properties, including both charge and spin orders, are strongly coupled with the kagome lattices.

Abstract Ammonia is a storage molecule for hydrogen, which can be released by catalytic decomposition. Inexpensive iron catalysts suffer from a low activity due to a too strong iron-nitrogen binding energy compared to more active metals such as ruthenium. Here, we show that this limitation can be overcome by combining iron with cobalt resulting in a Fe-Co bimetallic catalyst. Theoretical calculations confirm a lower metal-nitrogen binding energy for the bimetallic catalyst resulting in higher activity. Operando spectroscopy reveals that the role of cobalt in the bimetallic catalyst is to suppress the bulk-nitridation of iron and to stabilize this active state. Such catalysts are obtained from Mg(Fe,Co)2O4 spinel pre-catalysts with variable Fe:Co ratios by facile co-precipitation, calcination and reduction. The resulting Fe-Co/MgO catalysts, characterized by an extraordinary high metal loading reaching 74 wt.%, combine the advantages of a ruthenium-like electronic structure with a bulk catalyst-like microstructure typical for base metal catalysts.

Abstract The reversible transformation of a nanohelix is one of the most exquisite and important phenomena in nature. However, nanomaterials usually fail to twist into helical crystals. Considering the irreversibility of the previously studied twisting forces, the reverse process (untwisting) is more difficult to achieve, let alone the retwisting of the untwisted crystalline nanohelices. Herein, we report a new reciprocal effect between molecular geometry and crystal structure which triggers a twisting-untwisting-retwisting cycle for tri-cobalt salicylate hydroxide hexahydrate. The twisting force stems from competition between the condensation reaction and stacking process, different from the previously reported twisting mechanisms. The resulting distinct nanohelices give rise to unusual structure elasticity, as reflected in the reversible change of crystal lattice parameters and the mutual transformation between the nanowires and nanohelices. This study proposes a fresh concept for designing reversible processes and brings a new perspective in crystallography.

Background: Breast squamous cell carcinoma (SCC) is an uncommon and highly aggressive variant of metaplastic breast cancer. Despite its rarity, there is currently no consensus on treatment guidelines for this specific subtype. Previous studies have demonstrated that chemotherapy alone has limited efficacy in treating breast SCC. However, the potential for targeted therapy in combination with chemotherapy holds promise for future treatment options.Case presentation: In this case report, we present a patient with advanced HER2-positive breast SCC, exhibiting a prominent breast mass, localized ulcers, and metastases in the lungs and brain. Our treatment approach involved the administration of HER2-targeted drugs in conjunction with paclitaxel, resulting in a sustained control of tumor growth.Conclusion: This case represents a rare occurrence of HER2-positive breast SCC, with limited available data on the efficacy of previous HER2-targeted drugs in treating such patients. Our study presents the first application of HER2-targeted drugs in this particular case, offering novel therapeutic insights for future considerations. Additionally, it is imperative to conduct further investigations to assess the feasibility of treatment options in a larger cohort of patients.

In this paper, the effect of TB2 additions on a noval Al–Mg–Sc alloy was studied, and the microstructure and mechanical properties of SLM-fabricated TiB2/Al–Mg–Sc alloys were investigated. The results showed that molten pool width increased and molten pool depth slightly decreased with TiB2 increase, due to the laser absorptivity of the TiB2/Al–Mg–Sc alloys higher than that of Al–Mg–Sc alloy under the same process parameters. The microstructure of SLM-fabricated TiB2Al–Mg–Sc alloys were composed of fine-grained, coarse-grained and columnar-grained regions, and the fine-grained region increased with the increase of TiB2 content. The recrystallization regions in SLM-fabricated TiB2/Al–Mg–Sc alloy decreased with the increase of TiB2 content, and TiB2 additions used as heterogeneous nucleation to refine grains, which can pin grain boundaries and prevent recrystallization during SLM process. TiB2/Al–Mg–Sc alloy with 1% TiB2 additions showed a relatively higher comprehensive mechanical properties, and the tensile strength is 483 MPa, the elongation is 15.8%. Tensile strength of 1%TiB2/Al–Mg–Sc alloy was increased by 37 MPa and the elongation is also increased by 2.1% compared with 0%TiB2/Al–Mg–Sc alloy, and 2%TiB2/Al–Mg–Sc alloy shown a relatively lower comprehensive mechanical properties due to its lower density and TB2 agglomerated.

Ciprofloxacin (CIP) is a kind of widely used fluoroquinolone antibiotic, and the widespread presence of CIP in aquatic environment has become a serious issue. Mechanochemical treatment (MCT), as an effective approach to degrade persistent organic pollutants, has many advantages of low cost, simplicity, and being environmentally innocuous. However, little attention has been paid to employing MCT to treat effluents containing CIP. In this study, MCT was introduced to degrade CIP in aquatic solutions. A series of CIP degradation experiments were conducted by a planetary ball mill, and the influences of main parameters on CIP degradation efficiency were investigated. Furthermore, an optimum combination was selected through orthogonal experiments, and CIP degradation efficiency could reach as high as 99% in certain conditions. Besides, the biotoxicity of CIP solution was also studied. MCT exhibits satisfying performance for degrading CIP in solutions, which makes MCT a promising approach to CIP elimination and also encourages further applications in treating effluents containing other organic pollutants. HIGHLIGHTS Mechanochemical treatment was used to degrade ciprofloxacin in solutions.; Influences of main parameters on degradation efficiency were studied.; Ciprofloxacin degradation efficiency could reach 99% under optimal conditions.;

The robustness of superhydrophobic objects conflicts with both the inevitable introduction of fragile micro/nanoscale surfaces and three-dimensional (3D) complex structures. The popular metal 3D printing technology can manufacture robust metal 3D complex components, but the hydrophily and mass surface defects restrict its diverse application. Herein, we proposed a strategy that takes the inherent ridges and grooves’ surface defects from laser powder bed fusion additive manufacturing (LPBF-AM), a metal 3D printing process, as storage spaces for hydrophobic silica (HS) nanoparticles to obtain superhydrophobic capacity and superior robustness. The HS nanoparticles stored in the grooves among the laser-melted tracks serve as the hydrophobic guests, while the ridges’ metal network provides the mechanical strength, leading to robust superhydrophobic objects with desired 3D structures. Moreover, HS nanoparticles coated on the LPBF-AM-printed surface can inhibit corrosion behavior caused by surface defects. It was found that LPBF-AM-printed objects with HS nanoparticles retained superior hydrophobicity after 150 abrasion cycles (~12.5 KPa) or 50 cycles (~37.5 KPa). Furthermore, LPBF-AM-printed ships with superhydrophobic coating maintained great water repellency even after 10,000 cycles of seawater swashing, preventing dynamic corrosion upon surfaces. Our proposed strategy, therefore, provides a low-cost, highly efficient, and robust superhydrophobic coating, which is applicable to metal 3D architectures toward corrosion-resistant requirements.

A TiB2/AlMgScZr composite was fabricated by selective laser melting (SLM) with direct powder mixing. The microstructure and mechanical properties of SLM-fabricated TiB2/AlMgScZr composites were investigated. Nearly fully dense and crack-free SLM-fabricated TiB2/AlMgScZr parts were obtained. The results showed that TiB2 formed a coherent relationship with the matrix and was swallowed by the solid–liquid interface as a nucleation point to refine grains during the SLM process. In addition, some TiB2 particles did not form a coherent relationship with the matrix, moving the solid–liquid interface at the grain boundary, which reduced the recrystallization fraction and refined the grains significantly. TiB2 also promoted the precipitation of Al3Sc and Al3Zr phases and increased the volume fraction of the Al3Sc and Al3Zr phases during the SLM process. The SLM-fabricated TiB2/AlMgScZr composites showed a very high ultimate tensile strength of ∼483 MPa and excellent ductility of ∼15.8%, which are higher than those of wrought Al alloys. The solid solubility of the Mg element slightly increased in the SLM-fabricated TiB2/AlMgScZr composites because of the high heating and cooling rate during the SLM process. The high heating and cooling rate caused discontinuous strain and Portevin–Le Chatelier effect and weakened the strengthening effect of TiB2 in SLM-fabricated TiB2/AlMgSc composites.

ObjectveEmotional brain-computer interface can recognize or regulate human emotions for workload detection and auxiliary diagnosis of mental illness. However, the existing EEG emotion recognition is carried out step by step in feature engineering and classification, resulting in high engineering complexity and limiting practical applications in traditional EEG emotion recognition tasks. We propose an end-to-end neural network, i.e., E2ENNet.MethodsBaseline removal and sliding window slice used for preprocessing of the raw EEG signal, convolution blocks extracted features, LSTM network obtained the correlations of features, and the softmax function classified emotions.ResultsExtensive experiments in subject-dependent experimental protocol are conducted to evaluate the performance of the proposed E2ENNet, achieves state-of-the-art accuracy on three public datasets, i.e., 96.28% of 2-category experiment on DEAP dataset, 98.1% of 2-category experiment on DREAMER dataset, and 41.73% of 7-category experiment on MPED dataset.ConclusionExperimental results show that E2ENNet can directly extract more discriminative features from raw EEG signals.SignificanceThis study provides a methodology for implementing a plug-and-play emotional brain-computer interface system.

We present a novel homebuilt scanning tunneling microscope (STM) with atomic resolution integrated into a cryogen-free superconducting magnet system with a variable temperature insert. The STM head is designed as a nested structure of double piezoelectric tubes (PTs), which are connected coaxially through a sapphire frame whose top has a sample stage. A single shaft made of tantalum, with the STM tip on top, is held firmly by a spring strip inside the internal PT. The external PT drives the shaft to the tip–sample junction based on the SpiderDrive principle, and the internal PT completes the subsequent scanning and imaging work. The STM head is simple, compact, and easy to assemble. The excellent performance of the device was demonstrated by obtaining atomic-resolution images of graphite and low drift rates of 30.2 pm/min and 41.4 pm/min in the X–Y plane and Z direction, respectively, at 300K. In addition, we cooled the sample to 1.6 K and took atomic-resolution images of graphite and NbSe2. Finally, we performed a magnetic field sweep test from 0 T to 9 T at 70 K, obtaining distinct graphite images with atomic resolution under varying magnetic fields. These experiments show our newly developed STM’s high stability, vibration resistance, and immunity to high magnetic fields.

Recently, there has been growing interest in using lightwave-driven scanning probe microscopy (LD-SPM) to break through the Abbe diffraction limit of focusing, yielding insight into various energy couplings and conversion processes and revealing the internal information of matter. We describe a compact and efficient optical cryostat designed for LD-SPM testing under magnetic fields. The exceptional multilayer radiation shielding insert (MRSI) forms an excellent temperature gradient when filled with heat conducting gas, which removes the requirement to install an optical window in the liquid helium cooling shell. This not only critically avoids the vibration and thermal drift caused by solid heat conduction but also minimizes light transmission loss. The application of gate valves and bellows allows a simpler and more effective replacement of the sample and working cell in the test cavity. ANSYS software is used for steady-state thermal analysis of the MRSI to obtain the temperature distribution and heat transfer rate, and the necessity of the flexible copper shielding strips is illustrated by the simulations. The topography and magnetic domain images of 45 nm-thick La0.67Ca0.33MnO3 thin films on NdGaO3(001) substrates under a magnetic field were obtained by a self-made lightwave-driven magnetic force microscope in this cryostat. The resolution and noise spectra during imaging reveal temperature stability and low vibration throughout the cryostat. The experience acquired during the development of this cryostat will help to establish cryostats of similar types for a variety of optic applications requiring the use of cryogenic temperatures.

Scanning tunneling microscopy (STM) can image material surfaces with atomic resolution, making it a useful tool in the areas of physics and materials. Many materials are synthesized at micron size, especially few-layer materials. Limited by their complex structure, very few STMs are capable of directly positioning and imaging a micron-sized sample with atomic resolution. Traditional STMs are designed to study the material behavior induced by temperature variation, while the physical properties induced by magnetic fields are rarely studied. In this paper, we present the design and construction of an atomic-resolution STM that can operate in a 9 T high magnetic field. More importantly, the homebuilt STM is capable of imaging micron-sized samples. The performance of the STM is demonstrated by high-quality atomic images obtained on a graphite surface, with low drift rates in the X–Y plane and Z direction. The atomic-resolution image obtained on a 32-μm graphite flake illustrates the new STM’s ability of positioning and imaging micron-sized samples. Finally, we present atomic resolution images at a magnetic field range from 0 T to 9 T. The above advantages make our STM a promising tool for investigating the quantum hall effect of micron-sized layered materials.

Magnetic Force Microscopy (MFM) is among the best techniques for examining and assessing local magnetic characteristics in surface structures at scales and sizes. It may be viewed as a unique way to operate atomic force microscopy with a ferromagnetic tip. The enhancement of magnetic signal resolution, the utilization of external fields during measurement, and quantitative data analysis are now the main areas of MFM development. We describe a new structure of MFM design based on a cryogen-free superconducting magnet. The piezoelectric tube (PZT) was implemented with a tip-sample coarse approach called SpiderDrive. The technique uses a magnetic tip on the free end of a piezo-resistive cantilever which oscillates at its resonant frequency. We obtained a high-quality image structure of the magnetic domain of commercial videotape under extreme conditions at 5 K, and a high magnetic field up to 11 T. When such a magnetic field was gradually increased, the domain structure of the videotape did not change much, allowing us to maintain the images in the specific regions to exhibit the performance. In addition, it enabled us to locate the sample region in the order of several hundred nanometers. This system has an extensive range of applications in the exploration of anisotropic magnetic phenomena in topological materials and superconductors.

In order to improve the prediction accuracy of pitting depth of 316L stainless steel instrument pipe in oily marine atmosphere， a direct discrete grey pitting depth prediction model (SCPSO-DDGM (1，1， λ)) based on improved particle swarm algorithm optimization was established.First， using pitting corrosion data from exposure experiments as an example， the DDGM (1， 1) model was established， and the model was dynamically improved by applying a new information-based variable weight weakening buffer operator and dimension-equivalent gray number supplementation.Then，a nonlinear variation inertia weight and sine-cosine learning factors were used to enhance the optimization ability and convergence speed of the Particle Swarm Optimization (PSO) algorithm， while a Gaussian perturbation strategy was introduced to improve PSO's ability to escape local optima.The SCPSO was then employed to optimize the weight parameter λ in the improved DDGM (1， 1，λ) model.Finally， simulation calculations were performed in MATLAB to analyze and compare the prediction results of the SCPSO-DDGM(1， 1， λ) model with those of the GM (1，1)，DDGM (1，1) and PSO-DDGM (1，1，λ) models.Results showed that during the time period of the study， the predicted depth of the optimized new model was highly consistent with the actual depth， and its performance was better than that of the comparison model.Overall， it was proved that the SCPSO-DDGM (1，1， λ) model can effectively predict the pitting depth of instrument tubes， which provides new ideas and methods for the corrosion research of instrument tubes.