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Two-dimensional (2D) intrinsic ferromagnetic (FM) materials are promising candidates for fabricating next generation high-performance spintronic devices. However, all experimentally verified 2D FM semiconductors have Curie temperature (Tc) far below room temperature, which hinders their practical applications. Based on first-principles calculations, a stable and previously undiscovered 2D CrGaS3 structure is predicted, which is a semiconductor with an indirect bandgap of 1.99 eV and displays out-of-plane magnetic anisotropy. More importantly, it exhibits high-temperature ferromagnetism, with Tc ranging between 520 and 814 K. The high Tc is attributed to the presence of both direct-exchange and super-exchange interactions that are ferromagnetic, along with the eg-px/py-eg super exchange having a zero virtual exchange gap. Furthermore, it has been observed that the magnetic anisotropy can be tuned by external strain. These findings indicate its potential as a promising candidate for the rapid development of 2D spintronic applications. [ABSTRACT FROM AUTHOR]

Traditional drilling methods often face difficulty meeting the demand for efficient and accurate coring under complex geological conditions. Cordless coring is an advanced technology that uses hydraulic lifting to carry out coring, which can achieve automation and automated and intelligent drilling operations. In this research, a new type of hydraulic lifting cordless coring drilling tool is designed. Moreover, a numerical simulation model of the fluid flow in the annulus between the spearhead and spool of the cordless coring drilling tool was established. Orthogonal simulation tests are carried out, and according to the orthogonal test data, a numerical prediction model of the spool annulus fluid field based on the Backpropagation Neural Network (BP neural network) is established. The prediction of the flow rate of the drilling fluid and the spool back-pressure ratio was obtained when the structural parameters of the spearhead and the spool annulus were different. A multi-objective optimization of the annulus flow structure of the cordless core drilling tool has been carried out. The optimization objectives include deciding the back pressure ratio of the spool overcoming the spring and the flow rate of the drilling fluid. According to the established nonlinear optimization model and based on the improved Non-dominated Sorting Genetic Algorithm II (NSGA-II) multi-objective optimization algorithm, it is verified that the convergence speed and diversity of the improved algorithm are better than those before the improvement. The simulation and experimental validation are carried out. It is verified that the flow rate of drilling fluid increased by 33.56% after optimization, and the force ratio was lowered by 5.825%. Finally, based on the simulation and optimization results, the φ96 cordless core drilling tool was manufactured on a trial basis, and on-site concrete drilling, coring, and hydraulic lifting operations were conducted for smooth coring and lifting. This study could provide an important scientific basis and technical support for the application and development of hydraulic lifting cordless coring technology. [ABSTRACT FROM AUTHOR]

Hyperspectral anomaly detection is a vital aspect of remote sensing as it focuses on identifying pixels with distinct spectral–spatial properties in comparison to their background representations. However, existing methods for anomaly detection in HSIs often overlook the spatial correlation between pixels by converting the three-dimensional tensor data into its folded form of independent signatures, which may lead to insufficient detection performance. To address this limitation, we develop an anomaly detection algorithm from a tensor representation perspective, which begins by separating the observed hyperspectral image into background and anomaly cubes. We leverage the tensor nuclear norm (TNN) to capture the inherent low-rank structure of background cube globally. This allows us to effectively model and represent the background information. To further improve the detection performance, we introduce spatial–spectral total variation (SSTV) for effectively promoting piecewise smoothness of the background tensor, aiding in the identification of anomalies. Additionally, we incorporate RX-derived attention weights-guided ℓ 2 , 1 norm. This encourages group sparsity of anomalous pixels, improving the precision of anomaly detection. To solve our proposed method, we employ the alternating direction method of multipliers (ADMM), ensuring guaranteed convergence and efficient computation. Through experiments on different kinds of hyperspectral real datasets, we have demonstrated that our method surpasses several state-of-the-art detectors. [ABSTRACT FROM AUTHOR]

Herein, using density functional theory, novel two-dimensional (2D) CrInX2 (X = S, Se, Te) structures are predicted to be practical ferromagnetic (FM) semiconductors. Phonon vibrations and molecular dynamics simulations verified their structural and thermodynamic stability. Sizable fully spin-polarized band gaps of 1.03 and 0.69 eV are found for CrInS2 and CrInSe2, while CrInTe2 exhibits half-metallic band nature (at 0 K with a perfect lattice). The high magnetic anisotropy energies are responsible for their long-range spin polarization. The Curie temperatures (Tc) are estimated to be 347, 397 and 447 K for CrInS2, CrInSe2 and CrInTe2, respectively, all well above the room-temperature. The high Tc originates from unusual FM direct exchange, the efficient super-exchange coupling between neighboring Cr eg-orbitals with zero virtual exchange gaps and the presence of dual Cr–X–Cr super-exchange channels. Our systematic study of the CrInX2 monolayer suggests that it could be a promising material for spintronics applications. [ABSTRACT FROM AUTHOR]

Uniaxial tensile behaviors of basalt fiber and basalt textile reinforced fine-grained concrete composites under the same fiber volume content with different curing cycles (7 days, 14 days, 21 days and 28 days) were investigated using acoustic emission technology (AE), specifically, including three types of basalt fibers (0.34%, 0.68% and 1.02%) and basalt textiles (1, 2 and 3). The results indicated that the tensile strength of specimens was positively correlated with the curing cycles. As the volume content of basalt fiber increased, the reinforcing effect on fine-grained concrete was improved. The Aveton-Cooper-Kelly (ACK) model was the starting point for analyzing the reinforcement mechanism of basalt textiles. Compared with basalt fibers, basalt textiles could significantly improve the cracking load, ultimate load, cracking displacement and ultimate displacement of fine-grained concrete. The specimens had obvious characteristics of strain hardening during the entire fracture process. The AE signals had a high correlation with the the load-displacement curves during entire experimental process. AE signals were classified to illustrate different fracture mechanisms: textiles slipping, textiles pulling out, matrix-textiles debonding and textiles breaking. AE technology was comprehensively used for the first time to compare and describe the uniaxial tensile properties of basalt fibers and basalt textiles reinforced fine-grained concrete composites. [ABSTRACT FROM AUTHOR]

The tetrahedral structure of the basalt fabric is damaged when it is corroded by hydroxide ions, which greatly limits its application in the field of construction engineering as a result of the concrete matrix present in a strongly alkaline environment (pH >12.5). In this investigation, the alkali-resistant basalt fabric was successfully assembled by structuring mussel-inspired polydopamine (PDA) and zirconia (ZrO2) coatings on fabric surfaces. SEM, SWCA, XRD, FI-IR, RS, and XPS were used to analyze them. The mechanical properties of the different basalt fiber bundles accelerated aging in sodium hydroxide solution were tested. The interfacial behavior between basalt fiber bundles before and after modification and concrete matrix was studied by the acoustic emission (AE) technique. The results illustrated that dense PDA and ZrO2 coatings were dropped onto the surface of the basalt fabric. After being corroded by alkali solution, the final strength retention ratio of modified fabrics was superior to the original basalt fabric. Load–displacement curves of interfacial behavior could be well correlated with AE data in different loading stages of damage initiation, evolution and propagation. A five-stage linear local bond-slip model was proposed to describe the interfacial process between a basalt fiber bundle and concrete. [ABSTRACT FROM AUTHOR]

In this study, the chopped basalt fiber (CBF) with different content and basalt fiber grilles (BFG) with different layers were composed with concrete matrix, respectively. The compressive, splitting tensile and flexural properties of concrete composites were studied by universal material testing machine. The cracks evolution law of specimens was analyzed to reveal the reinforcement mechanism of CBF and BFG. Results showed that under the same fiber volume ratio, BFG were better than CBF to reinforce mechanical properties of concrete. The three kinds of mechanical properties of BFG reinforced concrete were improved highest by 41.46%, 28.26% and 46.13%, respectively. BFG can play a crucial role in stress transmission, bearing load and absorbing energy during the loading process of the specimens. Based on the equivalent stress rectangle theory, an analytic model to predict the ultimate flexural capacity of BFG reinforced concrete was proposed. The experimental results from the flexural test were compared with the predicted values, and a good accuracy of the analytic model was obtained. [ABSTRACT FROM AUTHOR]

In order to solve the problem of liquid electrolyte leakage caused by surface corrosion of metal relics, a portable in-situ detection gel probe suitable for field operation is designed. The probe uses KCl gel electrolyte, and a three-electrode system is constructed with platinum mesh, Ag/AgCl electrode and metal relics surface. The electrochemical impedance spectroscopy (EIS) is used to test the rusted cast iron samples and the iron relics in the Forbidden City to verify the probe. The results show that the impedance curves obtained by KCl solution and gel electrolyte are similar in shape, and the phase angle has no obvious change. At the same time, the gel electrolyte is used to monitor the timeliness of tannic acid as a protective material. The results show that the charge transfer resistance of the iron relics soaked in tannic acid for 6 h increases by 54.16 %, the double layer capacitance decreases by 31.97 %, and the diffusion impedance increases by 1.44 times. The gel probe can effectively overcome the electrolyte leakage of the solution, simplify the pretreatment process, realize the in-situ monitoring of the protection effect of metal relics, and judge the action time of the protective materials, which provides the basic conditions for the teaching and research of metal relics. [ABSTRACT FROM AUTHOR]

The poor alkali resistance of basalt fabric greatly affects the mechanical properties of textile reinforced concrete. In this study, dense zirconia coating obtained by sol-gel method was coated on the basalt fabrics surface as additional sizing to improve the alkali resistance of basalt fabrics. The morphology, wettability and phase composition of the fabric surfaces was characterized by scanning electron microscopy (SEM), static water contact angle (SWCA), X-ray powder diffraction (XRD), fourier transform infrared spectra (FI-IR), X-ray photoelectron spectroscopy (XPS) and Raman. The tensile properties of various basalt fabrics immersed in alkaline solution for different time and the mechanical property of concrete composites were examined by universal material testing machine. Results showed that a protective membrane was formed on the surface of basalt fabrics to prevent the diffusion of hydroxide ions. The final strength retention ratio of BF-c-ZrO2 (Basalt fabric-coated-Zirconia) fabrics could maintain at 89.92% compared with that of pristine basalt fabrics, which reached below 40%. The compressive strength and flexural strength of BF-c-ZrO2 fabrics reinforced concrete increased by 10.15% and 19.0% compared with that of pristine basalt fabrics reinforced concrete. A theoretical model was proposed to predict the ultimate flexural bearing capacity of BF-c-ZrO2 fabric reinforced concrete based on the equivalent stress rectangle theory. The corresponding predicted value compared with experimental result indicated a good coincidence and a reasonable accuracy, which was less than 5% of their discrepancy. [ABSTRACT FROM AUTHOR]

The research work is conducted to investigate the influence on the dynamic mechanical properties of concrete with different volume content of basalt fibers and the different layers number of basalt fabrics, as well as the hybrid effect between fibers and fabrics. The relationships among the impact force, impact time, displacement of the specimens and their failure patterns were analyzed. The results showed that the basalt fabric could significantly improve the brittleness and the impact resistance of concrete. Moreover, the impact force and energy absorption of the specimens increased continuously with the increase of impact energy. The fabrics could play the vital roles in transmitting stress, absorbing energy and bearing load. Basalt fiber could enhance the impact resistance of concrete but it was not obvious. Finally, the different reinforcement mechanisms of basalt fiber and basalt fabric under impact load were proposed. [ABSTRACT FROM AUTHOR]