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HighlightsN-Ti3C2@CNT microspheres are successfully synthesized by the simple spray drying and one-step pyrolysis.Within the microsphere, MXene nanosheets intimately interact with CNTs constructing porous and highly conductive network, which can provide strong immobilization for polysulfides.N-Ti3C2@CNT microsphere/S cathode shows highly cycling stability in lithium-sulfur battery.

Geothermal recovery involves a coupled thermo-hydro-mechanical (THM) process in fractured rocks. A fluid transient equilibrium equation, considering thermal conduction, convection, and heat exchange, is established. The evolution of the reservoir permeability and the variance in the fracture aperture due to a change in the stress field are derived simultaneously. THM coupling is accomplished through iterative hydromechanical and thermo-hydro processes. To overcome the difficulty of geometric discretization, a three-dimensional THM coupler model embedded with discrete fracture networks, using a zero-thickness surface and line elements to simulate fractures and injection/production wells, is established to evaluate the geothermal production. The reliability of the method is verified by a case study. Then, this method is applied to evaluate the influence of the geometric topological characteristics of fracture networks and the fracture aperture on the reservoir temperature evolution and heat extraction effectiveness. The results show that the power generation efficiency and geothermal depletion rate are significantly affected by the injection–production pressure. Injection wells and production wells with pressures higher than the initial fluid pressure in the fractures can be used to significantly increase power generation, but the consumption of geothermal energy and loss of efficiency are significant and rapid. To achieve better benefits for the geothermal recovery system, an optimization algorithm based on simultaneous perturbation stochastic approximation (SPSA) is proposed; it takes the power generation efficiency as the objective function, and the corresponding program is developed using MATLAB to optimize the position and pressure values for each production well. The results show that the heat transfer for the entire EGS reservoir becomes more uniform after optimization, and the heat transfer efficiency is greatly improved.

Equivalent hydraulic aperture and fracture surface roughness are two significant factors affecting the fluid flow behaviors in rock fractures. To understand the role of fracture surface roughness and aperture in the fluid flow through 3D self-affine rough fractures, roughness fracture surfaces with joint roughness coefficients equal to 2.5, 7.5, 12.5, and 17.5 were established, and the Navier–Stokes equation was used to compute the fluid flow in these 3D self-affine rough fractures with a mechanical aperture increase from 0.2 mm to 0.8 mm with a gradient of 0.2 mm. The results show that when the fracture mechanical aperture is 0.2 mm, the impact of fracture surface roughness on fluid flow is considerable, while this effect decreases obviously with the increase of fracture mechanical aperture. Comparing the permeability obtained by the Navier–Stokes equation with the cube law under different hydraulic gradients, we found that their deviation increased with the increase of hydraulic gradients. This allows for the definition of a critical hydraulic gradient (Jc), below which the permeability can be properly predicted using the cubic law for its simplicity, and above which Forchheimer’s equation should be applied, and Forchheimer’s coefficients A, B, and Jc can be calculated by the prediction equations established in this study.

A flash flood disaster is one of the most destructive natural disasters. With the increase in extreme rainfall events, more and more areas will be threatened by flash floods. The flash flood susceptibility assessment is the basis of flash flood risk assessment and is also an important step in flash flood disaster management. Based on Citespace analysis tools, this study made a bibliometric and visualized analysis of 305 documents collected in the core collection of Web of Science in the past 15 years, including the analysis of the number of publications and citation frequency, influence analysis, keyword analysis, author co-citation analysis, and institutional co-operation analysis. This paper summarizes the current research status and future development trend of flash flood susceptibility assessment from five key research subfields, including assessment scale, assessment unit, assessment index, assessment model, and model assessment method, discusses the analysis of the application of remote sensing and GIS in flash flood susceptibility assessment, discusses the problems encountered in the current research of the five subfields, and provides suggestions for flash flood hazard control.

The roller is the connect structure between the gripper and main or auxiliary gearbox, which rotates simultaneously with the aluminum billet. When preheating short aluminum billet, a part of the roller is in the air-gap, which will be heated during preheating the aluminum billet, and the increase in the temperature of the roller can affect the gearbox. To address the roller heat, a magnetic shielding method has been proposed. And the effect of the magnetic shielding of the magnetic field in the roller and the air-gap has been analyzed. The weakening effect of the magnetic shielding on the heating power also has been evaluated. At the same time, the electromagnetic force of the magnetic shielding is also been carried out. The results show that the magnetic shielding can effectively reduce the heating power of the roller. Evidently, adding a magnetic shielding around the roller is feasible to alleviate or solve the problem of roller and gripper heat.

Liver ischemia-reperfusion injury (IRI) serves as a critical pathological basis for post-hepatectomy liver failure and graft dysfunction following liver transplantation. Excessive inflammatory responses, oxidative stress, and cell death are key mechanisms underlying IRI. The lack of multi-targeted therapies contributes to the current insufficiency in clinical IRI management. This study developed endothelial-targeting VHPKQHR peptide (VHP)-modified ginseng-derived exosomes (G-Exos) loaded with IL-6 small interfering RNA (Si-IL6) (siRNA@VG-Exos) to mitigate liver IRI. VHP modification facilitated the targeted delivery of siRNA@VG-Exos to damaged endothelium, promoting their accumulation and subsequent release at the IRI site. siRNA@VG-Exos effectively reduced hepatic inflammatory cytokine release, enhanced T-SOD and CAT expression while suppressing MDA generation, thereby alleviating oxidative stress. Furthermore, they promoted the restoration of mitochondrial membrane potential, maintaining mitochondrial homeostasis. Si-IL6 additionally suppressed IL-6 expression in liver tissue, synergistically enhancing the anti-inflammatory effect of G-Exos. Moreover, siRNA@VG-Exos inhibited CD86 expression and promoted CD206 expression in hepatic macrophages, facilitating their polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype and modulating immunity. Ultimately, siRNA@VG-Exos reduced hepatic necrotic areas, lowered ALT and AST levels, and restored liver tissue function. Further sequencing analysis indicated that siRNA@VG-Exos alleviates liver IRI by inhibiting immune and inflammatory responses and oxidative stress damage. Therefore, siRNA@VG-Exos provides a novel targeted strategy for the treatment of liver IRI. Graphical Abstract This study developed endothelial-targeting VHPKQHR peptide (VHP)-modified ginseng-derived exosomes (G-Exos) loaded with IL-6 small interfering RNA (Si-IL6) (siRNA@VG-Exos) to mitigate liver IRI. siRNA@VG-Exos provides a novel targeted strategy for the treatment of liver IRI.

This study uses a 2D hydro-morphological model to analyze hydrodynamics over flat and deformed beds with a near-bank vegetation patch. By varying the patch density, the generalized results show that the hydrodynamics over deformed beds differs a lot from those over flat beds. It is found that the deformed bed topography leads to an apparent decrease in longitudinal velocity and bed shear stress in the open region and longitudinal surface gradient for the entire vegetated reach. However, the transverse flow motion and transverse surface gradient in the region of the leading edge and trailing edge is enhanced or maintained, suggesting the strengthening of secondary flow motion. Interestingly, the deformed bed topography tends to alleviate the horizontal shear caused by the junction-interface horizontal coherent vortices, indicating that the turbulence-induced flow mixing is highly inhibited as the bed is deformed. The interior flow adjustment through the patch for the deformed bed requires a shorter distance, La, which is related to the vegetative drag length, (Cda)−1, with a logarithmic formula (La = 0.4ln[(Cda)−1] + b, with b = 3.83 and 4.03 for the deformed and flat beds). The sloping bed topographic effect in the open region accelerating the flow may account for the quick flow adjustment.

This paper presents experimental studies on hydrodynamics and bed morphological characteristics under varying water and sediment discharges over a gravel channel bed with a boulder. Firstly, flow characteristics over a non-eroded bed with a mild slope were investigated. Results show that along the transect line located one diameter away from the boulder centerline, the existence of the boulder has negligible impact on the mean flow characteristics, which are similar to flows over a flat bed. At the boulder centerline, the flow is largely deflected by the boulder and turbulence characteristics in the horizontal plane are largely enhanced in the wake of the boulder. Secondly, water scour experiments were carried out over a steep slope. It could be observed that scour occurred around the boulder and bedloads were deposited downstream, forming a typical pool–riffle sequence. An analysis shows that the length scale (L/D) of geometric features associated with pool depth, riffle height and pool–riffle distance (S/D) are positively related to the boulder-related Froude number (Frb): L/D = 1.18Frb − 0.11 and S/D = 12.5Frb + 0.6; and the erosion volume (Ve) for flat bed and boulder bed is positively and negatively related to the averaged Froude number (Fr): Ve/D3 = 37.1Fr − 21.3 and Ve/D3 = −44.8Fr − 38.6, where D is the boulder diameter.

Compared with a small magnet, the magnet for IMW HTS DC induction heater is larger, and the radius reaches up to 2200mm, which will bring great difficulties to the winding of superconducting magnets. To ensure that the design and fabrication of the large-diameter HTS DC magnet can be a one-shot success, some smaller HTS magnets, including three 200 mm diameter magnets and two 600 mm diameter magnets, have been designed and fabricated. The structure of these magnets is similar to the final 2200 mm diameter prototype magnet, which is wound in a spiral way. Performance test results of all the superconducting magnets have proved that the winding process and curing process of the magnet is feasible and can be used to make large-diameter magnets formally.

Flash flood early warning is a very effective way to reduce casualties induced by rainstorm flash flood in mountainous area. The forecasting of flash flooding remains challenging because of the short response time and inaccurate warning threshold. So far, the flash flood disaster defenses often adopt the critical rainfall amounts inducing the peak discharge or water level to establish an early warning threshold in China. However, the runoff peak discharge depends on rainfall patterns including rainfall intensity and accumulation, result in the critical rainfall threshold has a significant uncertainty. To reduce this uncertainty, herein we present a dual-threshold method for flash flood early warning with consideration of rainfall patterns based on above two-rainfall metrics. Moreover, applying this new method in the flash flood disasters occurred in the Zhongdu river basin, Sichuan province of China to evaluate the early warning reliability. Firstly, five most likely rainfall patterns of this basin were determined according to the timing of rain peak in historical rainfall events, and then, we determined the critical rainfall thresholds under different rainfall patterns and soil moisture conditions. The result showed that the rainfall thresholds uncertainty caused by rainfall pattern is more pronounced than soil moisture. Next, using the cumulative rainfall depth and maximum rainfall intensity corresponding to disaster discharge in different flood processes to establish the dual-thresholds. We found the dual-threshold method comprehensively considers the impacts of soil moisture, rainfall temporal distribution and flood rising property, which can achieve early warning for the four protected objects along the Zhongdu River, with an average lead duration of 46.2 min. Compared with the other three single-threshold methods, the critical rainfall and the critical rainstorm curve methods frequently created false or missing warnings, making it difficult to achieve the effect of early warning. Although reliability of flood water level rising rate method is high, the lead time is relatively short and only lasts for a few minutes in some cases. As a result, the new proposed dual-threshold method, accounting for both the reliability and long lead time, can be a potential candidate for the flash flood disaster early warning.