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The shape of the blast casting muck pile in surface coal mines is an important factor that affects the operational efficiency and cost of the blast casting pulling shovel stacking process system. In order to improve the accuracy of predicting the shape of blast casting muck piles in surface coal mines, further optimize the design of blast casting, and reduce the cost of blast casting stripping, based on the measured data of blast casting in the Heidaigou surface coal mine, an example analysis was conducted. The entropy method grey correlation method was used to study the weight and correlation between the impact indicators of blast casting effect and the farthest throwing distance, looseness coefficient, and effective throwing rate. The correlation between hole spacing, section width and the evaluation indicators of blast casting effect is relatively low. The minimum resistance line, row spacing, explosive consumption, step height, lower mouth width of goaf, slope angle, and upper mouth width of goaf were selected as input parameters for the prediction model. The Gaussian distribution model was introduced to simulate the profile curve of the blast casting muck pile. By using a 1–8th order Gaussian distribution model to simulate and analyze the detonation profile curve, it was determined that the simulation accuracy and efficiency reach an optimal level when the order is 5. The trained HHO–LSSVM was used to predict 15 parameters of the 5th order Gaussian distribution model, which were used as the control parameters for predicting the output detonation shape. And the Gaussian distribution model combined with the HHO–LSSVM algorithm was used to predict the shape of the blast casting muck pile, compare the accuracy of the LSSVM, Particle Swarm Optimization (PSO) optimized Least Squares Support Vector Machine, and Genetic Algorithm (GA) optimized BP neural network models, at the same time, compare the predicted blast casting muck pile morphology with the actual blasting muck pile morphology. The results show that the sum of squared errors (S) parameter of the blasting muck pile morphology curve simulated using a 5th order Gaussian distribution tends to stabilize at 25.69, and the coefficient of determination (R2) and adjusted coefficient of determination (\begin{document}$R_{\mathrm{A}}^2 $\end{document}) are 0.999 2 and 0.999 0, respectively. The root mean square error (R) is 0.514 6. The prediction error of the HHO–LSSVM for the 5th order Gaussian distribution control parameters is mostly around 1%, and the error does not exceed 5%, compared with the LSSVM, PSO, and GA–BP algorithm models, the accuracy is higher. Taking the profiles E5–8, E5–9, and E5–10 as examples, the errors R2 and R between the predicted and actual detonation morphology are 0.998 7 and 0.614 2, 0.999 2 and 0.493 1, 0.999 2 and 0.505 2, respectively, the predicted shape of the blasting muck pile is close to the actual shape of the blasting muck pile morphology.

Abstract Prussian blue (PB) is regarded as a promising cathode for sodium‐ion batteries because of its sustainable precursor elements (e.g., Mn, Fe), easy preparation, and unique framework structure. However, the unstable structure and inherent crystal H2O restrain its practical application. For this purpose, a self‐constructed trace Mg2+/K+ co‐doped PB prepared via a sea‐water‐mediated method is proposed to address this problem. The Mg2+/K+ co‐doping in the Na sites of PB is permitted by both thermodynamics and kinetics factors when synthesized in sea water. The results reveal that the introduced Mg2+ and K+ are immovable in the PB lattices and can form stronger K‒N and Mg‒N Coulombic attraction to relieve phase transition and element dissolution. Besides, the Mg2+/K+ co‐doping can reduce defect and H2O contents. As a result, the PB prepared in sea water exhibits an extremely long cycle life (80.1% retention after 2400 cycles) and superior rate capability (90.4% capacity retention at 20 C relative to that at 0.1 C). To address its practical applications, a sodium salts recycling strategy is proposed to greatly reduce the PB production cost. This work provides a self‐constructed Mg2+/K+ co‐doped high‐performance PB at a low preparation cost for sustainable, large‐scale energy storage.

DC link capacitors (DCLCs) are key devices in converters. The relative humidity affects the performance of the elements of a DCLC. Currently, there are relatively few studies on the effect of relative humidity on the electrical characteristics of the elements of DCLCs during the production process. This study describes the effects and the control of the relative humidity in the production process. For this purpose, a DCLC component withstand voltage test platform and a DCLC component aging test platform were established. The voltage withstand tests were conducted during different processes and at different relative humidities, and life aging tests were conducted at different relative humidities and different storage times. The results show that after the winding and metal-spraying processes, the voltage withstand levels of the components stored at 30% RH, 60% RH, and 80% RH were very close to that of the components at 3000 VDC; after the heat-setting process, the voltage withstand levels of the components stored at 30% RH, 60% RH, and 80% RH showed a decreasing tendency compared with the level of the components at 3000 VDC. Regarding the samples, after the heat-setting process, stored at 30% RH and 60% RH for 24 h, 96 h, 168 h, 240 h, and 336 h and 2000 h of the aging tests, the capacitance decreases monotonically as the storage time is increased but never exceeds 3%, and the capacitance change decreases as the relative humidity increases. This study can provide important guidance for the humidity control of various processes in the production of DCLCs.

P2-type layered oxide cathodes suffer from poor capacity retention and detrimental phase transitions at high voltage due to the presence of Na vacancies. During deep desodiation, irreversible lattice oxygen release increases capacity but also accelerates lattice collapse. In this work, to address the capacity limitations of the P2-type layered oxide cathode and leverage its structural stability, we develop a high-voltage P2-type layered oxide cathode, Na0.84La0.01Li0.12Ni0.22Mn0.66O2 (P2-NLLNMO). The La-doped material exhibits less volume variation (1.8%) and more stable crystal structure over a wide voltage window of 2.0–4.5 V. P2-NLLNMO yields a high capacity of 136.6 mAh g–1 and excellent cycling stability (89.2% retention after 200 cycles at 0.5 C) with a cutoff voltage 4.5 V. In addition, we reveal that La–O orbital hybridization is important for the enhanced performance when La atoms are doped in Na layers of P2-NLLNMO. This discovery provides valuable insights and guidance for the design of P2-type cathodes in high-energy-density sodium-ion batteries.

Mechanical stress is a crucial factor affecting the life and insulation performance of DC-link capacitors (DCLCs). However, at present, there is a lack of long-term experimental observations on the effects of mechanical stress on the life and insulation performance of DCLCs. The element-winding process for DCLCs is carried out by winding metalized film on a reel and adjusting the various winding tensions and pressures according to performance requirements, usually with a winding tension coefficient (WTC) of kT = 1.5. The pull pressure of the winding machine on the film produces tension during the elements’ winding process, and the tension in the film grows after the heat-setting process. In this study, by adjusting the four tension coefficients of the elements in the winding process, which were 1.4, 1.5, 1.6, and 1.7, various winding tensions of the DCLC components were changed. Additionally, various heat-setting shrinkage tensions were appropriately generated by setting different heat-setting temperatures (HSTs). Relevant test platforms were established, and a life aging test, insulation resistance measurement, and withstand voltage test were performed on these DCLCs at different tension coefficients and HSTs. The obtained results reveal that the mechanical stress of DCLCs is affected by the parameters of the material itself, including the tension coefficient during the winding process and the HST. The winding tension affects the life of DCLCs, such that those with the highest tension (kT = 1.7) demonstrate the longest life at an HST of 105 °C, whereas samples with the lowest tension (kT = 1.4) exhibit the longest life at an HST of 110 °C. HSTs are capable of improving the lifetime of DCLCs. HSTs are also able to improve the withstand voltage capability of DCLCs, but the tension is not proportional to the withstand voltage capability of DCLCs. This research provides a suitable basis for further explorations of the life and insulation performance of DCLCs.

Insulation resistance is a vital factor in dry DC link capacitors (DCLCs), and crucially influences their voltage equalization and energy storage performance. However, at present, there is a lack of experimental observation on the insulation resistance characteristics of DCLCs in the presence of high temperatures and operating voltages. In the present study, the insulation resistance and conductivity of DCLCs are methodically analyzed. For this purpose, the corresponding test platform is appropriately fabricated, the insulation resistance measurement experiments are performed at various temperatures and operating voltages, and the factors affecting the insulation resistance and conductivity of the DCLC are carefully examined. The results reveal that the insulation resistance of the DCLC reduces exponentially with the growth in voltage and operating temperature. When the operating voltage becomes greater than 4480 V or the operating temperature reaches higher than 70 °C, the decline in insulation resistance slows down. The conductivity of metalized polypropylene film in the DCLC increases exponentially with increasing voltage and temperature. By increasing the operating voltage from 1960 V to 5600 V and the temperature from 20 °C to 90 °C, the DCLC’s insulation resistance exhibits a descending trend from 891.30 MΩ to 2.14 MΩ, while its conductivity grows from 3.49 × 10−16 S/m to 1.47 × 10−13 S/m. The results reveal that the key factors affecting the insulation resistance of the DCLC are the polypropylene film and the metal evaporated from the metal layer. This research is anticipated to provide a valuable reference for the further development of science and technology pertinent to the insulation resistance of DCLCs.

Significant bone remodeling with disordered osteoclastogenesis has been implicated in the pathogenesis of psoriatic arthritis (PsA). And there is a high prevalence of the metabolic syndrome (MS) in PsA patients. Adipokines, especially leptin and adiponectin, have recently been reported to be involved in the development and regulation of some autoimmune diseases. In this study, we examined the alternation of circulating osteoclastogenesis related cytokines [tumor necrosis factor-α (TNF-α), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL)] and adipokines (leptin, adiponectin, resistin, chemerin, omentin) in PsA patients, and analysed the correlations between these factors and osteoclast precursors numbers, radiographic damage scores, and disease activity index. 41 PsA patients, 20 psoriasis patients, and 24 healthy controls were recruited. Blood samples were obtained for detecting the levels of TNF-α, OPG, RANKL and the adipokines. The numbers of osteoclast precursors (OCs) in peripheral blood were assessed. Radiographs of affected joints in PsA patients were scored for erosion, joint-space narrowing, osteolysis, and new bone formation. Compared with healthy controls, patients with PsA had higher TNF-α, RANKL, OCs, leptin and omentin but lower adiponectin and chemerin. Increased serum levels of TNF-α, RANKL, leptin, and omentin were positively correlated with OCs numbers. In contrast, serum adiponectin levels were decreased in PsA patients and negatively correlated with OCs numbers. TNF-α, RANKL and leptin were positively correlated with Psoriatic Arthritis Joint Activity Index (PsAJAI). Only TNF-α was positively correlated with radiographic damage scores. Our data demonstrated that systemic expression of soluble mediators of osteoclastogenesis and adipokines were disordered in PsA. Certain adipokines were elevated in the circulation of patients with PsA and might contribute to pathogenesis of arthritis. Prospective studies will be of interest to determine the pluripotent effects of adipokines on osteoclastogenesis in chronic inflammatory rheumatic diseases. Future studies may lead to novel therapeutic strategies.