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The existing researches have concluded that the number of gravity heat pipes, insertion depth and angle, filling rate, working fluid will affect the distribution of the internal temperature field of coal pile. However, there are few researches on the optimal arrangement of gravity heat pipes in coal pile. In order to solve the above problems, based on the gravity heat pipe heat transfer theoretical model, the heat source is equivalent to a sphere, and the effect of gravity heat pipe arrangement on the high temperature point of coal pile is analyzed by a combination of numerical simulation and experiment, and the optimal arrangement of gravity heat pipe is derived. The numerical simulation results based on Comsol software show that the depth of gravity heat pipe insertion has greater effect on the temperature of the high-temperature heat source point inside coal pile than the inclination angle of gravity heat pipe insertion. Under the same angle, the greater the gravity heat pipe arrangement depth is, the better. This means that the closer to the heat source, the better. Under the same depth, when the gravity heat pipe arrangement angle is 60, 90, 45 and 30°, the cooling range decreases in order. When the insertion depth of gravity heat pipe is 60 cm and the insertion angle is 60°, the highest cooling range reaches 61.2 ℃, and the coal pile has the best cooling effect. The experimental results based on the coal storage pile heat transfer test bench show that the optimal arrangement of gravity heat pipes is consistent with the simulation results, and the overall trend of the cooling rate is similar to the simulation results. With the increase of the inclination angle, the cooling rate of heat pipe decreases first and then increases, and the cooling rate reaches the maximum when the inclination angle of heat pipe insertion reaches 60°.

High‐temperature aqueous zinc batteries have recently garnered significant attention for large‐scale energy storage. However, spontaneous hydrogen evolution and passivation on the Zn metal anode severely affect its cycling stability under elevated temperature conditions. Herein, a facile strategy is employed to construct a bifunctional composite protective layer comprising an insulating ZnF2 layer combined with Zn affinity conductive tin (Sn) metal. This combination optimally distributes Zn ions (Zn2+) and maintains consistent thermal field distribution around Zn anodes. Moreover, the presence of fluorides on the interface efficiently suppresses the hydrogen evolution reaction, while the Sn metal serves as nucleation seeds with reversible alloying and dealloying process to endow dendrite‐free morphology and fast reaction kinetics. Specifically, the symmetric cell with the coated electrode exhibits excellent stability at a current density of 3 mA cm−2 over 420 h at 50 °C. When coupled with the modified Zn anode and I2 cathode, the Zn//I2 full cells deliver high areal capacity and substantiate their practical application, exhibiting remarkable high‐temperature resilience over 2000 cycles with 97.8% capacity retained at 50 °C. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZBs) degrade under a high current density due to the existence of interfacial turbulence with severe concentration polarization. Herein, an ion redistribution gel electrolyte is introduced to stabilize the electrode‐electrolyte interface by regulating the ion density gradient. Negatively charged carboxymethyl groups in carboxymethyl starch ether polymer (PCMS) electrolytes can preferentially regulate the ion concentration at the anode interface. The quasi‐solid PCMS gel electrolytes can dissipate the charge accumulation caused by ion concentration differences, which is beneficial for achieving excellent electrochemical stability at high current densities. As a result, the symmetric Zn cells with PCMS gel electrolyte can be cycled for more than 2000 h at a high current density of 40 mA cm−2. Furthermore, the Zn//I2 cell using PCMS gel electrolyte also sustained cycling for over 8000 cycles, and the pouch cell with PCMS gel electrolyte exhibited practical deformable applications in flexible devices. This work highlights an effective gel electrolyte approach for enhancing interfacial stability, potentially advancing the development of highly reversible AZBs. [ABSTRACT FROM AUTHOR]

Background: Hybrid surgery (HS) combined cervical disc arthroplasty (CDA) with anterior cervical discectomy and fusion (ACDF) is emerging, but its biomechanical effects as a revision surgery (RS) on adjacent segments were unclear. Objectives: This finite element (FE) study aimed to investigate the biomechanical characteristics of HS to treat two‐level discontinuous ASD in ACDF RS. Methods: A C2‐T1 intact FE model was established and modified to a primary C5/6 ACDF model and five RS models. These RS models' segments C4/5 and C6/7 were revised using cage plus plate (C), zero‐profile devices (P), and Bryan disc (D), respectively, generating C‐C‐C, P‐C‐P, D‐C‐P, P‐C‐D, and D‐C‐D models. In the intact and C5/6 ACDF models, a 1.0 Nm moment was used to produce the range of motion (ROM). A displacement load was applied to all RS models, to achieve a total ROM match that of the primary C5/6 ACDF model. Results: In the P‐C‐P model, biomechanical responses including ROM, Intradiscal pressure (IDP), Facet joint force (FJF), and Maximum von Mises stresses of discs at segments C3/4 and C7/T1 were slightly lower than the C‐C‐C model. The biomechanical response parameters at segments C3/4 and C7/T1 of P‐C‐D, D‐C‐P, and D‐C‐D were smaller than those in C‐C‐C and P‐C‐P models. D‐C‐D had the most significant effect on reducing all biomechanical responses among all RS models in segments C3/4 and C7/T1. Moreover, the disc stress cloud maps showed that the maximum von Mises stress of the C3/4 disc was higher than that of C7/T1. Conclusions: D‐C‐D, P‐C‐D, and D‐C‐P are good RS choices for reducing the biomechanical responses, and D‐C‐D was the best choice. P‐C‐P can be the best recommendation when it does not meet the CDA indications. This study provided a biomechanical reference for hybrid surgical decision‐making in the ACDF RS for preventing ASD recurrence. [ABSTRACT FROM AUTHOR]

In this paper, PHREEQC software was used to calculate the saturation index of insoluble minerals, the pH boundary values of precipitated CaCO3, and the boundary values of Ca2+ and HCO3− concentrations in relation to the uranium extraction process and the chemical composition of leaching in the Nalinggou uranium deposit. Based on the comparative analysis results of the mineral composition and chemical composition of the primary rock and the blockage, the formation of the blockage containing the mineral layer is mainly related to the pH-value and the corresponding ion concentration of the leaching solution, the sediment can be effectively avoided in the boundary value range. [ABSTRACT FROM AUTHOR]

Based on the chemical composition of the leaching solution in the acid leaching uranium test, the characteristics and critical values of mineral dissolution and precipitation of Hadatu uranium ore in Inner Mongolia under different acidity were explored by using PHREEQC simulation software. The chemical composition of the leaching solution and the change characteristics of the main trace elements of the original and slag samples were systematically analyzed. The changes of the existing forms of uranium and iron during leaching were studied. The content of feldspar and clay mineral and the changes of permeability coefficients were studied, and the changes of saturation index in the process of uranium leaching such as gypsum, gibbsite, hematite, goethite, Fe(OH)3 and Al2O3 were calculated. The results show that acidity is the main factor of mineral dissolution, and the dominant order of cation leaching is ∑Fe>Ca2+>Mg2+> Al3+>Na+>K+, and the main forms of uranium and iron in the leaching process are UO2SO4, UO22+ and UO2(SO4)22-, Fe2+ and FeSO4. When the acidity of the leaching solution was 10 g/L, Ca2+ concentration was less than 503. 2 mg/L, pH value was below 2. 94, and no precipitation of gypsum and iron-aluminum minerals would be produced. In the uranium leaching test, compared with the original samples, the content of slag feldspar decreased by 1. 10%-5. 70%, and the clay mineral increased by 0. 62%-4. 15%, indicating that clay alteration occurred in column leaching. Gypsum, iron-aluminum mineral precipitation, and clay-altered feldspar are important reasons for the significant decrease in permeability. [ABSTRACT FROM AUTHOR]

This paper studies the influence of the staged particle sieving-out method on the seepage characteristics in loose sandstone heap leaching. The staged sieving out of ore sample particles was conducted according to particle size, and ground pressure was applied to them. Subsequently, parameters such as the permeability, particle distribution, and pore distribution characteristics of the rock samples were obtained to investigate the influence of the staged particle sieving-out method on the seepage effect of loose sandstone heap leaching. The results indicate that sieving out particles smaller than 0.15 mm can significantly reduce the probability of hole blockage and increase the overall pore size, greatly enhancing permeability. Sieving out particles with sizes between 0.15 mm and 1.2 mm can result in the loss of skeleton particles, reducing the amount of flow channels and thereby decreasing permeability. Sieving out particles larger than 1.2 mm can reduce the overall particle size of rock samples, improve strength and pressure stability, and help maintain permeability. In the surface heap leaching of loose sandstone ore, by sieving out particles smaller than 0.15 mm during deep heap construction and sieving out particles larger than 1.2 mm during mid-level heap construction, and by using vat leaching for sieved-out particles, the seepage effect of the ore heap can be significantly optimized, and complete utilization of resources can be ensured. [ABSTRACT FROM AUTHOR]

With the development of Internet and 5G, new social media has been constantly developing and updating. People are getting more and more used to get information from social media. People’s lives have been filled with applications, such as TikTok and Instagram. These applications not only bring much fun and convenience to people, but also make it possible for people’s fragmented time to be used wisely. However, at the same time, many people, especially teenagers with poor self-control, would easily be overdependent on the social media. As one of the most famous social media at present, with the help of big data, TikTok has successfully made some teenagers seriously depend on its platform by inferring the users’ minds and accurately showing them the content they demand. This paper takes TikTok as a case study and teenagers as the research object to analysis the reasons why teenagers use social media habitually, and provide some reasonable solutions to reduce teenagers’ media dependency. In short, teenagers get addicted to TikTok primarily because of their self-control is not strong enough so that they fell into the trap of TikTok. TikTok and other social media use big data to predict users’ preference, and take advantage of users’ psychology to make teenagers get addicted to social media without realizing. In order to get rid of the traps, network supervision departments should strengthen the management, TikTok and other social media should recommend more useful short videos to teenagers, and teenagers themselves can also take advantage of big data.

The concentration of uranium in the rock sample was 35.0 μg/g, the concentration ratio of CO2 and O2 injected was 1:1, the autoclaves pressure was 0.02 MPa. The uranium leaching rate varied from 28.70 to 37.97%, and when the concentration of HCO3− is lower, the output rate of U is significantly increased as it increases, when its concentration exceeds the threshold value, U's output concentration is no longer infinitely increased. Calcite and dolomite were saturated and precipitated during the leaching process due to the high initial pH; with the injection of CO2, calcite and dolomite remained near- or under-saturated and did not precipitate. [ABSTRACT FROM AUTHOR]