Search

Adding a certain amount of steel fibers can overcome the brittleness defects in geopolymer concrete and improve the mechanical properties, which has a broader application prospect. However, the research on the material properties of steel fiber-reinforced geopolymer concrete (SFGPC) after high temperature exposure is still very limited. Therefore, tests on 114 cubes and 57 prisms after exposure to high temperatures were conducted in this paper. The main variables were temperature (20 °C, 200 °C, 400 °C, 600 °C, and 800 °C), steel fiber volume content (0, 1 %, and 2 %), and concrete type (SFGPC and steel fiber-reinforced ordinary Portland cement concrete (SFOPC)). The results indicated that SFGPC with a steel fiber content of 1 % at 800 °C experienced a 53.6 % reduction in compressive strength, a 58 % reduction in splitting tensile strength, a 93.9 % reduction in elastic modulus, a 45.9 % reduction in toughness index, and a 274.5 % increase in peak strain, compared with room temperature. The 1 % fiber content enhanced the compressive strength by 10.3 %−36.5 %, the splitting tensile strength by more than 16 %, the peak strain by 9.6 %−32.7 %, and the toughness index by 24.4 %−64.6 % compared to the absence of fiber content. Based on the room temperature model, a constitutive model of SFGPC under uniaxial compression after high temperatures was developed. • Cubes and prisms of SFGPC after high temperature exposure were tested. • High temperature reduced the strength, elastic modulus, and toughness index. • Increasing fiber content enhanced the mechanical behavior of SFGPC. • A constitutive model under compression after high temperatures was developed. [ABSTRACT FROM AUTHOR]

Large-seed-induced regulation significantly impacts perovskite film grain growth; however, it inadequately addresses stress and defect issues at the perovskite interface. To counter this, we introduce an innovative self-disintegrating seed approach, employing 2D (4-FBZA) 2 PbI 4 perovskite to enhance the crystallization process. During perovskite crystal growth, (4-FBZA) 2 PbI 4 could disintegrate and release 4-FBZA+ ions. These ions effectively anchor the perovskite interface and interact with FA+ and [PbI 6 ]4- within the lattice, passivating defects and releasing detrimental stress. This strategy results in reduced nonradiative recombination and residual stress, culminating in perovskite solar cells (PSCs) achieving a champion power conversion efficiency (PCE) of 23.73 % and a remarkable fill factor of 83.64 %. Crucially, unencapsulated PSCs retain over 90 % of their initial PCE following 2000 h of exposure in ambient conditions at 25±5 °C and 60 % relative humidity. [Display omitted] • A self-disintegrating seed strategy is proposed to improve the quality of perovskite films. • The interface modification and stress releasement brought by self-disintegrating seed are systematically demonstrated. • Perovskite solar cells with enhanced performance and stability are achieved. [ABSTRACT FROM AUTHOR]

The amorphous formation ability, thermal properties, crystallization behavior, magnetic properties, resistivity and bending ductility of Fe 84.5- x B 12 P 2 C 1 Cu 0.5 Co x (x = 0, 4, 8) alloys were systematically investigated. It is found that the substitution of Fe by Co promotes the transformation of the as-spun alloys from a completely amorphous structure to an amorphous/nanocrystalline dual-phase structure, which is related to the differences in the interactions between the involved atoms. The saturation magnetization of alloys increases with increasing Co content and can be increased to 1.93 T at x = 8 by heat treatment, but excessive substitution of Co for Fe deteriorates the coercivity and bending ductility due to the pre-existing α-Fe(Co) grains. The resistivity is positively correlated with the disorder of structure, and the as-spun alloy with x = 4 exhibits a high resistivity of 136.2 μΩ cm. As a result, the annealed Fe 80.5 B 12 P 2 C 1 Cu 0.5 Co 4 alloy with excellent soft magnetic properties (M s = 1.81 T, H c = 7.8 A/m) and good bending ductility in combination with high resistivity has potential for application in the field of electronic devices. • The crystallization tendency of alloy is enhanced by the substitution of Fe by Co. • The annealed Co4 alloy exhibits an ultrafine nanocrystalline structure. • Co4 alloy combines excellent soft magnetic properties with high resistivity. • Co0, Co4 Alloys exhibit good bending ductility even when annealing at T x1 -60 K. [ABSTRACT FROM AUTHOR]

Emulsified asphalt offers energy-saving and environmental benefits, aligning with low-carbon, high-quality development requirements. However, poor adhesion hampers the development of emulsified asphalt. The hydrophilic group substituent position significantly influences the adhesive strength at the emulsified asphalt/aggregate interface. To further elucidate this mechanism, this study employs molecular dynamics (MD) simulation techniques, focusing on the positional variations of the hydrophilic group in the sodium dodecylbenzene sulfonate molecule, particularly the SDBS2–1#, SDBS3–1#, and SDBS4–1# configurations. The objective is to enhance adhesion between these two materials. The simulation results were validated through macroscopic demulsification experiments, encompassing a comprehensive analysis of various parameters, including relative concentration distribution, diffusion coefficient, adhesion work, electron density difference, and electrostatic potential distribution. The result demonstrated a strong synergistic effect between the emulsifiers' molecular structure and the aggregates' chemical composition. The emulsifier SDBS4–1# with para-substitution enhances adhesion at the interface between the emulsified asphalt and alkaline aggregate (CaCO₃) by 50.4 %. The emulsifier SDBS2–1# with ortho-substitution enhances adhesion at the interface between the emulsified asphalt and acidic aggregate (SiO₂) by 33.3 %. Furthermore， the emulsifiers SDBS4–1# and SDBS2–1# promote the accumulation of electrons in asphalt molecules on CaCO₃ and SiO₂ surfaces, respectively. This increase in electron accumulation enhances the adhesion performance between emulsified asphalt and aggregate at their interface. Therefore, optimizing the structure of emulsifier molecules significantly increases the bonding strength between emulsified asphalt and aggregate surfaces. [Display omitted] • Increasing the spacing of substituents on the phenyl functional group enhances the adsorption capacity of emulsified asphalt. • The emulsifier （SDBS2–1#） with ortho substitution reduces the diffusion of asphalt molecules on SiO 2 surfaces and promotes a stable adsorption layer. • The emulsifier (SDBS4–1#) with para-substituted molecules significantly increases the adhesive strength and electron accumulation of asphalt on the CaCO₃ surface. [ABSTRACT FROM AUTHOR]

To ensure that underwater remotely operated vehicles have the ability to complete trajectory tracking in the presence of external disturbances and model parameter uncertainties, this paper proposes a double-closed-loop integrative sliding mode ROV tracking control based on the nonlinear expansion state observer. Firstly, to address the issue of oscillatory vibrations in the stable state of the dual closed-loop sliding mode structure, the inner loop control adopts a combinatorial reaching rate that leverages both exponential and variable convergence rates. Secondly, addressing the impact of external disturbances and model parameter uncertainties on the ROV, this paper proposes a novel nonlinear disturbance observer inspired by active disturbance rejection control principles. The stability of the complete closed-loop cascaded system is substantiated. Simulation outcomes demonstrate that the presented scheme significantly enhances the control system's transient response, disturbance rejection capacity, and ability to suppress jitter vibrations within sliding mode control, thereby proving the robustness, viability, and effectiveness of the control strategy outlined herein. • Proposed a dual loop sliding mode control strategy based on a nonlinear extended state observer. • Designed a nonlinear extended state observer based on the ROV model to handle external disturbances. • Application of a composite convergence rate to solve the problem of inner-loop jitter in a double-loop control structure. [ABSTRACT FROM AUTHOR]

During tumor development, the tumor itself must continuously generate new blood vessels to meet their growth needs while also allowing for tumor invasion and metastasis. One of the most common features of tumors is hypoxia, which drives the process of tumor angiogenesis by regulating the tumor microenvironment, thus adversely affecting the prognosis of patients. In addition, to overcome unsuitable environments for growth, such as hypoxia, nutrient deficiency, hyperacidity, and immunosuppression, the tumor microenvironment (TME) coordinates angiogenesis in several ways to restore the supply of oxygen and nutrients and to remove metabolic wastes. A growing body of research suggests that tumor angiogenesis and hypoxia interact through a complex interplay of crosstalk, which is inextricably linked to the TME. Here, we review the TME's positive contribution to angiogenesis from an angiogenesis-centric perspective while considering the objective impact of hypoxic phenotypes and the status and limitations of current angiogenic therapies. [Display omitted] • A close interactive link exists between tumor angiogenesis, hypoxia, and TME, collectively promoting tumorigenesis and progression. • Growth factors in the tumor microenvironment are secreted and regulated by various cell types, and a significant correlation exists between their expression levels and hypoxia. • The development of anti-angiogenic therapy is hampered by the lack of accurate biomarkers, the uncertain time window of medication, and the widespread problem of drug resistance. [ABSTRACT FROM AUTHOR]

Ligilactobacillus murinus , a member of the Ligilactobacillus genus, holds significant potential as a probiotic. While research on Ligilactobacillus murinus has been relatively limited compared to well-studied probiotic lactic acid bacteria such as Limosilactobacillus reuteri and Lactobacillus gasseri , a mounting body of evidence highlights its extensive involvement in host intestinal metabolism and immune activities. Moreover, its abundance exhibits a close correlation with intestinal health. Notably, beyond the intestinal context, Ligilactobacillus murinus is gaining recognition for its contributions to metabolism and regulation in the oral cavity, lungs, and vagina. As such, Ligilactobacillus murinus emerges as a potential probiotic candidate with a pivotal role in supporting host well-being. This review delves into studies elucidating the multifaceted roles of Ligilactobacillus murinus. It also examines its medicinal potential and associated challenges, underscoring the imperative to delve deeper into unraveling the mechanisms of its actions and exploring its health applications. • Ligilactobacillus murinus is a potential probiotic distributed in the intestines, oral cavity, lungs and vagina. • Ligilactobacillus murinus in the intestine can indicate the degree of health status of the host. • Single Ligilactobacillus murinus is distinguished from Ligilactobacillus murinus in microbial communities. • Ligilactobacillus murinus , emerging as a potential probiotic, is critical for safety assessment and clinical studies when used as probiotic drugs. [ABSTRACT FROM AUTHOR]

With the explosive increase of remote sensing data, how to search for remote sensing data quickly and accurately in a vast dataset is an incredibly critical matter for research subjects. The deep hashing method has become the dominant method for remote sensing image retrieval because of its low-cost storage and high-speed retrieval. However, for the reason of the limitation of fixed convolutional kernels, deep hashing frameworks based on Convolutional Neural Networks (CNNs) fail to obtain the global semantic information well, which leads to the generation of suboptimal solutions. Furthermore, existing hashing methods commonly employ the random sampling strategy or hardest sample mining to build training batches, resulting in bad local minima. To remedy these problems, a novel Deep Global Semantic Structure-preserving Hashing framework via corrective triplet loss (DGSSH) is proposed for remote sensing image retrieval to learn a discriminative and stable embedding space, achieving intra-class confusion and inter-class diversity. Specifically speaking, the feature extraction module based on Swim Transformer architecture is developed to capture global semantic information and multiscale features from remote sensing images. Based on a distribution matching constraint, the corrective triplet loss for deep hashing schemes is designed to reduce the distribution shift caused by the random selection or hardest sample mining. Meanwhile, to reduce the time overhead of the model, the asymmetric learning strategy is employed to perform effective compact representation learning. Numerous experiments have been carried out on three publicly available benchmarks, which indicates that the proposed DGSSH framework could achieve optimal performance for remote sensing image retrieval applications. The source code of our DGSSH framework is hosted at https://github.com/QinLab-WFU/DGSSH.git. • The Swim Transformer architecture is developed to capture global semantic features. • The corrective triplet loss is proposed to reduce the distribution shift. • An asymmetric learning strategy is employed to improve training efficiency. • The state-of-the-art results are reported on three benchmark datasets. [ABSTRACT FROM AUTHOR]

Based on the coupling algorithm of smoothed particle hydrodynamics and finite element method, numerical simulation of high-velocity water jet impacting heterogeneous concrete containing aggregates according to the real concrete CT slices was conducted to study the damage evolutions and fracture characteristics of concrete with real structure. The damage evolution and fragmentation process of heterogeneous concrete were obtained, and the fracture characteristic was compared with homogeneous concrete. The internal energy change laws and the damage and stress evolutions in homogeneous and heterogeneous concretes at different time were investigated. And the failure mechanisms of water jet crushing heterogeneous concrete were revealed. The results show that the concrete elements mainly suffer multi-stage plastic damage accumulation failure induced by water jet impact due to stress wave effect, pressured water wedge effect, water flow scouring effect, squeezing effect of aggregate, and stress concentrations. The failures of upper and deep concrete elements are mainly caused by compressive shear stress, which is combined with tensile stress. In homogeneous concrete, the bowl-shaped broken pit with smooth sidewall and the symmetrically distributed cracks are formed. In heterogeneous concrete, the aggregate will prolong the damage accumulation process and lead to the formation of the abnormal broken pit with irregular and rough contour. Cracks prefer to propagate at interface between aggregate and mortar, and concrete elements at interfaces will suffer the sudden brittle failure caused by stress concentration when the damage accumulates to a certain extent. Overall, the internal energy in concrete first rapidly and then slowly increases, and there is a poorer absorption efficiency of jet kinetic energy for heterogeneous concrete, in which the internal energy of aggregates and mortar is closely related to the specific impact object of water jet. The research results would lay the theoretical foundation for water jet efficiently crushing concrete. [Display omitted] • Water jet impacting concrete with actual aggregates was simulated and verified. • Damage evolution and fragmentation process were investigated. • Energy changes and damage-stress evolutions were compared. • Failure mechanisms of heterogeneous concrete were revealed. [ABSTRACT FROM AUTHOR]