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To address the problem that traditional cement-based slurry materials cannot meet the actual demand for grouting and reinforcement of large deformation roadways in coal mines, some high-performance composite slurry materials are obtained by modifying ordinary Portland cement with nano-silica sol, ethylene-vinyl acetate copolymer (EVA) and fly ash. The orthogonal test and extreme difference analysis are used to systematically study the variation of the physical and mechanical properties of the composite slurries, determine the optimal ratio, and further analyze the difference in the physical properties between the optimal ratio of composite slurries and pure cement, construct the hydration reaction mechanism model of the composite slurries, and elucidate the mechanical properties of the composite slurries for reinforcing broken rocks. The results of the study show that the optimum proportion of composite slurry is 0.7 water-cement ratio, 15% fly ash, 2% silica sol and 7.5% EVA. Compared with pure cement, the rheology of composite slurry is slightly decreased, but the stability and mechanical properties of the slurry are significantly improved, with the initial setting time shortened by 38.9%, the final setting time shortened by 53.8%, the precipitation rate reduced by 60%, the stone rate increased by 3.3%, the uniaxial compressive strength increased by 39.1%, the tensile strength increased by 97.2%, and the tensile/compression ratio increased by 41.7%. Silica sol and fly ash undergo volcanic ash reaction with Ca(OH)2 to generate more calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H) at different times, which promotes the hydration reaction of the composite slurry and accelerates the film formation of EVA to make the stone body more dense. The injection volume of the composite grout and the uniaxial compressive strength of the bonded body both increase with the increasing grouting pressure. With the increase in the Talbot index, the compressive strength first increases and then decreases. The failure mode is often characterized by bulging, and shear dilation deformation is pronounced. When the grouting pressure exceeds 2 MPa and the Talbot index is 0.5, the bond strength of the grout is higher, and the damage is reduced. This study provides a feasible way for early strength and toughening modification of ce-mentitious composite pastes.

Objective Despite the established success of total knee arthroplasty (TKA) with end‐stage osteoarthritis, there is a notable scarcity of research on its long‐term outcomes in individuals suffering from end‐stage Kashin–Beck disease (KBD). This retrospective study aimed to assess the long‐term outcomes and effectiveness of clinical function, quality of life, and complications of TKA and end‐stage KBD patients in Tibetan highland areas. Methods The retrospective cohort included 43 KBD patients, comprising a total of 59 knees, who had undergone TKA at West China Hospital, Sichuan University between 2008 and 2021. Patients were subsequently followed up for a minimum of 3 years, and received rigorous radiological and clinical assessments at 3, 6, and 12 months post surgery, followed by annual examinations thereafter. The evaluation included various efficacy indices, including visual analogue scale (VAS) scores, hospital for special surgery (HSS) scores, functional score for adult Tibetans with Kashin–Beck disease (FSAT‐KBD), and radiographic findings. Comparison of indicators within the same group was conducted using one‐way repeated‐measures analysis of variance or paired sample t‐tests, whereas between‐group differences were compared using an independent t‐test. Results Throughout the average follow‐up duration of 10.8 years, patients experienced a substantial reduction in knee pain and noteworthy functional improvement. The VAS scores decreased significantly from 77.47 ± 4.12 mm before surgery to 10.91 ± 1.97 mm after surgery, indicating considerable alleviation of knee pain. The HSS scores improved markedly, increasing from 44.26 ± 4.95 preoperatively to 91.26 ± 4.37, indicating enhanced joint function. Similarly, the FSAT‐KBD exhibited positive progression, increasing from 25.90 ± 3.12 to 36.95 ± 3.54. Importantly, at the last follow‐up, none of the patients presented with periprosthetic infection, prosthesis loosening, or periprosthetic fracture. Conclusion At long‐term follow‐up, compared with patients in the preoperative period, patients in Tibetan highland areas with KBD of the knee who underwent TKA benefited from a significant reduction in pain, improvement in joint function, and satisfactory improvement in quality of life.

Abstract Bacground The aim of this study was to assess the learning curve of a novel seven-axis robot-assisted total hip arthroplasty (RaTHA) system. Methods A total of 59 patients who underwent unilateral total hip arthroplasty at our institution from June 2022 to September 2022 were prospectively included in the study. In this randomized controlled clinical trial, robot-assisted THA (RaTHA) and Conventional THA (CoTHA) were performed using cumulative sum (CUSUM) analysis to evaluate the learning curve of the RaTHA system. The demographic data, preopera1tive clinical data, duration of operation, postoperative Harris Hip Score (HHS), postoperative Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, and duration of operation between the learning stage and the proficiency stage of the RaTHA group were compared between the two groups. Results The average duration of operation of the RaTHA group was increased by 34.73 min compared with the CoTHA group (104.26 ± 19.33 vs. 69.53 ± 18.38 min, p

Abstract In this paper, the tribological characteristics of an oil-soluble magnetic fluid additive under mixed lubrication are studied by experiments and numerical simulation. [bmim][FeCl4] is dissolved in CF10W-40 lubricating oil as a magnetic liquid additive, and its friction coefficient is tested by a point contact friction tester at different temperatures, rotational speeds and magnetic field intensities. The transition condition of lubrication state is obtained through analyzing the Stribeck curves based on the experiments, and the strength model of boundary film is established accordingly. A mixed lubrication model is established by substituting the boundary film strength model and the surface roughness model into the hydrodynamic lubrication model based on Reynolds equation. The results show that the magnetic solution as an additive can obviously reduce friction and wear, and the effect is more obvious under the condition of magnetic field. The boundary film strength model can accurately reflect the transition characteristics of lubrication state in the presence of boundary film, and the mixed lubrication model based on boundary film strength model can more precisely reflect the tribological characteristics of friction pairs, so this study provides a new theoretical method for the related research on the influence of boundary film on lubrication characteristics.

Electrokinetic remediation technology can effectively remove heavy metal ions from contaminated soil in coal mine area. In order to clarify the effect of electric field on the adsorption characteristics of heavy metal ions on the surface of kaolinite, three common heavy metal elements Pb(II), Cd(II) and Cu(II) in mine soil were studied, a three-dimensional visualization model was established, and a stable kaolinite-solution-kaolinite simulation system was optimized. Molecular dynamics simulation method was used. The adsorption mode, atomic density distribution, diffusion coefficient and radial distribution function of heavy metal ions on kaolinite (001) crystal plane under electric field were investigated. The results show that when the electric field direction is +Z, the electric field promotes the complexation between heavy metal ions and siloxane surface, and the coordination number of the first hydration shell of heavy metal ions decreases with the increase of electric field intensity. The adsorption percentage of outer complexes increases with the increase of electric field intensity. When the electric field direction is −Z, the adsorption percentage of the outer complex decreases with the increase of the electric field intensity, the interaction between the kaolinite surface and heavy metal ions weakens, and more heavy metal ions dissociate in the solution and pair with chloride ions; under the action of electric field polarization, there is no obvious boundary between the first and second hydration shells of heavy metal ions, and there is water molecular exchange between the hydration shells; under the action of electric field, the MSD curve of heavy metal ions on kaolinite shows anisotropy. The diffusion coefficient in X and Y direction is larger than that in Z direction, the total diffusion coefficient increases with the increase of electric field intensity, and the diffusion coefficient is not obviously affected by the positive and negative direction of electric field. Pb(II) ion and Cd(II) ion only have outer complexes on the surface of kaolinite, while Cu(II) ions have the adsorption mode of coexistence of inner and outer complexes. The adsorption priority of kaolinite to three heavy metal ions is Pb(II) > Cu(II) > Cd(II).

Abstract Aims Robot-assisted total hip arthroplasty (rTHA) boasts superior accuracy in implant placement, but there is a lack of effective assessment in perioperative management in the context of enhanced recovery after surgery (ERAS). This study aimed to compare the effectiveness and safety of rTHA versus conventional total hip arthroplasty (cTHA) in ERAS-managed patients. Methods In this prospective trial, a total of 60 eligible patients aged between 18 and 80 years were randomly divided into two groups to undergo either rTHA or cTHA. The primary outcomes included blood loss parameters. Secondary outcomes were the duration of the operation, surgical time, WOMAC pain score, WOMAC stiffness score, WOMAC physical function score, Harris score, and postoperative complications. Results The study cohort analyzed 59 eligible participants, 30 of whom underwent rTHA and 29 of whom underwent cTHA. Analysis could not be conducted for one patient due to severe anemia. Notably, the cTHA group had a significantly shorter surgical time than the rTHA group (69.49 ± 18.97 vs. 104.20 ± 19.63 min, P

Selenium (Se) is an essential trace element for humans. Low concentrations of Se can promote plant growth and development. Enhancing grain yield and crop Se content is significant, as major food crops generally have low Se content. Studies have shown that Se biofortification can significantly increase Se content in plant tissues. In this study, the genetic transformation of wheat was conducted to evaluate the agronomic traits of non-transgenic control and transgenic wheat before and after Se application. Se content, speciation, and transfer coefficients in wheat grains were detected. Molecular docking simulations and transcriptome data were utilized to explore the effects of selenium-binding protein-A TaSBP-A on wheat growth and grain Se accumulation and transport. The results showed that TaSBP-A gene overexpression significantly increased plant height (by 18.50%), number of spikelets (by 11.74%), and number of grains in a spike (by 35.66%) in wheat. Under normal growth conditions, Se content in transgenic wheat grains did not change significantly, but after applying sodium selenite, Se content in transgenic wheat grains significantly increased. Analysis of Se speciation revealed that organic forms of selenomethionine (SeMet) and selenocysteine (SeCys) predominated in both W48 and transgenic wheat grains. Moreover, TaSBP-A significantly increased the transfer coefficients of Se from solution to roots and from flag leaves to grains. Additionally, it was found that with the increase in TaSBP-A gene overexpression levels in transgenic wheat, the transfer coefficient of Se from flag leaves to grains also increased.

This study introduces a low-friction composite based on PEEK to improve its friction and wear properties. The composite incorporates PTFE as a solid lubricant and utilizes PPTA as a reinforcing material within the PEEK matrix. These components were prepared utilizing a compression molding method, followed by a series of exploratory experiments to identify the optimal preparation conditions for PEEK. This research assesses how the PTFE/PPTA/PEEK composites perform in terms of friction and wear under dry and oil-lubricated conditions. By examining wear tracks using scanning electron microscopy and white light interference microscopy, this study aims to uncover the wear mechanisms of PEEK and its composites under different lubrication scenarios. Results show that the main wear mechanisms for the PTFE/PPTA/PEEK composites and bearing steel are ploughing and adhesive wear. The presence of PPTA helps reduce wear by leveraging its strong fibers and thermal stability, while the coefficient of friction decreases as PTFE creates a smooth, solid lubricating film on the surface. Notably, PEEK composites containing 25 wt% PTFE and 6 wt% PPTA demonstrate the lowest wear rates and reduced coefficient of friction in both dry and oil-lubricated conditions.

This study investigates the effect of the elastic surface micro-texture on the cavitation and lubrication characteristics of the friction pairs through theoretical and experimental research. Through numerical simulations and experiments, the influences of the elastic modulus and sliding speed on the lubrication performance of the friction pair are studied. The results show that under certain speed and load conditions, the friction coefficient of the elastic texture is smaller, and the lubrication performance is better than that of the rigid texture. Increasing the sliding speed and texture spacing properly can improve the lubrication performance of elastic friction pairs. In addition, as the elastic modulus decreases, the elastic deformation and oil film thickness increase, and the cavitation phenomenon becomes more significant. Thus, the lubrication performance of the friction pair is improved.

In view of the problems of low early strength and weak deformation resistance of ordinary cement-based materials, the cement-based materials were modified by nano-silica sol. The nano-silica sol was charasterized by means of electro-hydraulic servo universal testing, X-ray diffraction, and scanning electron microscopy. The fluidity, stone rate, uniaxial compressive strength, elastic modulus, hydration products, and microstructure of cement-based materials with different water-cement ratios were evaluated. The results show that when the content of silica sol is within 0.5% and the water-cement ratio is less than 1.0, the fluidity of cement slurry can be significantly improved, and the maximum increase is 20.24%. The stone formation rate increases with the increase of nano-silica sol admixture, and the silica sol increases the stone formation rate of slurry with water-cement ratio greater than 0.7 significantly, with a maximum increase of 24.49%. When the content of silica sol is 2%, the compressive strength of the stone body increases the most. The effect of increasing the strength gradually weakens. The incorporation of nano-silica sol promotes the early hydration reaction of cementitious, and reacts with the hydration products to produce hydrated calcium silicate gel (C—S—H) and makes the microscopic morphology more dense, so that the early compressive strength and elastic modulus of the stone body are significantly increased. Nano-silica sol promotes the hydration reaction by shortening the induction period and providing nucleation sites for C—S—H in the particle voids, which improves the performance of cementitious materials.

[Introduction] Coupling electrochemical energy storage equipment with thermal power plants is a feasible solution to improve the flexible peaking capacity of power system under the high proportion penetration of renewable energy power. [Method] The function and application characteristics of electrochemical energy storage technology in thermal power plants were introduced firstly. Then the characteristics of electrochemical energy storage technology were summarized and concluded. Meanwhile, the applicability of different types of electrochemical energy storage systems for different application purposes scenarios was analyzed. According to the current application and bottleneck of electrochemical energy storage technology in thermal power plants, the development direction of electrochemical energy storage technology is discussed. Finally, the development direction of electrochemical energy storage technology was prospected. [Result] According to the analysis results, although the electrochemical energy storage technology has a broad engineering application prospect in thermal power plants, there is still room for improvement in operation safety, construction and maintenance costs, material recovery, and other aspects. [Conclusion] Operation strategy optimization, development of new high-performance materials, and equipment safety and recycling management will become the main development directions of electrochemical energy storage technology participating in the application process of thermal power frequency modulation in the future.

[Introduction] In order to adapt to the demand of the original thermal power units for new energy power consumption, improving its peak regulating capacity is one of the key factors. The heat storage system is an important way of "thermoelectric decoupling" of coal-fired thermal power units, so it has engineering reference value to evaluate its parameter matching. [Method] A method of coupling heat storage device was used to increase the depth peak regulation capacity of coal-fired unit. Combined with the power curve of heat load and electric load, the influence law of heat storage device parameters was systematically studied. [Result] The results show that with the regional load curve as a typical case, when the heat storage capacity and charging and releasing rate parameters of the heat storage tank increase, the heat load regulation capacity of the unit reaches 112.75 MW and 129 37 MW·min respectively, and the depth peak regulation parameter is about 110 MW. Besides, the heat storage capacity and the heat charging and discharge rate match, and the bottleneck factors will directly restrict the depth peak regulation performance of the system. [Conclusion] By integrating the boundary situation of heat storage and heat discharge, the role of the heat storage tank in the auxiliary peak regulation process is accurately demonstrated. Combined with the optimization design of its operation strategy, the parameter matching relationship of the heat storage auxiliary peak regulation system can be further analyzed to provide a reference for the parameter design of the coupled thermal storage system of thermal power units.

[Introduction] The proposal of the "carbon peak and neutrality" goal increases the necessity of new energy power embedding. To study the method to improve the flexibility of the unit, this paper introduces the flywheel energy storage technology and the related research of the coupled generator set in detail. [Method] The working principle, research status, and achievements of flywheel energy storage as well as application difficulties and measures were summarized, and the specific methods of studying the system modeling and operation strategy of flywheel energy storage were analyzed, and the principle and application characteristics of flywheel energy storage coupled with thermal power generation, wind power generation and solar power generation were analyzed emphatically. [Result] This paper shows that the research on flywheel energy storage systems in China has achieved relatively advanced results and formed a set of effective research methods, and some research has been done on the coupling of flywheel energy storage technology with multi-energy generator set. [Conclusion] In today's environment, flywheel energy storage technology coupled with multi-energy generators has become a research trend and focus, the summary of this paper provides a reference for the subsequent application of flywheel energy storage technology.

Abstract In this paper, the surface texture parameters and distribution patterns are studied by numerical simulation and experiment. First, a three-dimensional micro-textured CFD fluid lubrication model with cavitation effect is established, and different texture arrays are designed to study the influence of different distribution modes on bearing capacity, friction coefficient and pressure distribution of the oil film. Then, the simulation results are further analyzed and verified by the visualized plane slider experimental platform, and the formation rules of cavitation bubbles in the micro-textured array, as well as the influences of the surface shape and different distribution modes of the micro-textured array on the cavitation bubbles are discussed. The results show that the existence of cavitation is one of the main reasons for the microtexture to increase the bearing capacity of the oil film, which cannot be ignored in the simulation study. The texture array with single symmetric orientation is the best to improve the oil film bearing capacity, and the bearing performance is the best when the texture inclination angle is 26.6°.The friction coefficient of the asymmetrically oriented textured array is 29.4% lower than that of the non-textured sample.The results in the experiment are consistent with the simulation.

As train operating speeds increase, the aerodynamic characteristics of the train within the tunnel become more pronounced, and effectively addressing the issue of micro-pressure wave (MPW) over-limits becomes especially crucial. This paper utilized the control volume method to investigate the key influencing parameters of tunnel exit hoods on the mitigation effectiveness of MPWs. Additionally, numerical simulation methods were used to validate these crucial parameters. The analysis considered various opening ratios, different opening forms, and the influence of hoods at tunnel entrances and exits on the amplitude and spatial distribution patterns of MPWs. A design methodology that comprehensively takes into account the advantages of tunnel entrance and exit hoods was proposed. The results showed that a higher opening ratio of tunnel exit hoods led to lower MPW amplitudes. Compared to without opening in the hood, when the opening ratio of the exit hood reached 90%, the maximum amplitude of MPWs at a distance of 20 m from the hood outlet decreased by 48.7%. Various opening forms of exit hoods resulted in distinct spatial distribution patterns of MPW amplitudes, with amplitudes near the openings notably higher than in other areas. There were differences in the mitigation mechanisms between entrance and exit hoods. In comparison to entrance hoods, exit hoods exhibited higher mitigation efficiency within a specific range of MPW amplitudes. Additionally, when both entrance and exit hoods were installed, they achieved the most effective mitigation of MPWs.

Cadmium, one of the toxic heavy metals, robustly impact crop growth and development and food safety. In this study, the mechanisms of wheat (Triticum aestivum L.) selenium-binding protein-A (TaSBP-A) involved in response to Cd stress was fully investigated by overexpression in Arabidopsis and wheat. As a cytoplasm protein, TaSBP-A showed a high expression in plant roots and its expression levels were highly induced by Cd treatment. The overexpression of TaSBP-A enhanced Cd-toleration in yeast, Arabidopsis and wheat. Meanwhile, transgenic Arabidopsis under Cd stress showed a lower H2O2 and malondialdehyde content and a higher photochemical efficiency in the leaf and a reduction of free Cd2+ in the root. Transgenic wheat seedlings of TaSBP exhibited an increment of Cd content in the root, and a reduction Cd content in the leaf under Cd2+ stress. Cd2+ binding assay combined with a thermodynamics survey and secondary structure analysis indicated that the unique CXXC motif in TaSBP was a major Cd-binding site participating in the Cd detoxification. These results suggested that TaSBP-A can enhance the sequestration of free Cd2+ in root and inhibit the Cd transfer from root to leaf, ultimately conferring plant Cd-tolerance via alleviating the oxidative stress and photosynthesis impairment triggered by Cd stress.

Activity of BC1 complex kinase (ABC1K) serves as an atypical kinase family involved in plant stress resistance. This study identified 44 ABC1K genes in the wheat genome, which contained three clades (I–III). TaABC1K genes generally had similar structural features, but differences were present in motif and exon compositions from different clade members. More type II functional divergence sites were detected between clade I and clade III and no positive selection site were found in TaABC1K family. The three-dimensional structure prediction by Alphafold2 showed that TaABC1K proteins had more α-helixes with a relatively even distribution, and different clade members had differences in the content of secondary structures. The cis-acting element analysis showed that TaABC1K genes contained abundant cis-acting elements related to plant hormones and environmental stress response in the promoter region, and generally displayed a significantly upregulated expression under drought stress. In particular, both TaABC1K3 and TaABC1K6 genes from clade I was highly induced by drought stress, and their overexpression in yeast and Arabidopsis enhanced drought tolerance by suppressing active oxygen burst and reducing photosynthesis impairment. Meanwhile, TaABC1K3 and TaABC1K6 could, respectively, complement the function of Arabidopsis abc1k3 and abc1k6 mutants and reduce photosynthesis damage caused by drought stress.

For the influence of boundary film on the lubrication state of sliding friction pairs, a boundary film strength model was proposed that can comprehensively reflect the influences of film thickness, pressure, shear stress and temperature. The model parameters were obtained through fitting the test results. Then, a mixed lubrication model considering boundary film strength was established by coupling the boundary film strength model with the hydrodynamic lubrication model and the asperity contact model. The calculation program was developed using the Fortran language, which can effectively capture the tribological characteristics and action ratios of the fluid, boundary film and dry friction components. Simultaneously, the mixed lubrication model was applied to the journal bearing. A parametric analysis was performed to investigate the influences of different working conditions on lubrication performance. Under current operating conditions, the results show that: when the speed is above 200 r/min or the viscosity is higher than 0.09 Pa·s, the boundary film breakdown rate is almost 0 and the friction coefficient is lower than 0.02; when the roughness is reduced from 1.8 μm to 0.8 μm, the ultimate load of the journal bearing rises from 27 MPa to 36 MPa, an increase of about 33%; when the load exceeds 36 MPa or the temperature is higher than 100 °C, more than 25% of the boundary film breaks and the dry friction component accounts for more than 60% of the total friction, which leads to a sudden increase in the friction coefficient. Hence, the study of mixed lubrication considering boundary film strength provides theoretical guidance for accurately reflecting the actual lubrication state and improving the mechanical energy efficiency of friction pairs.

GATA transcription factor genes participate in plant growth, development, morphogenesis, and stress response. In this study, we carried out a comprehensive genome-wide analysis of wheat GATA transcription factor genes to reveal their molecular evolutionary characteristics and involvement in salt and drought tolerance. In total, 79 TaGATA genes containing a conserved GATA domain were identified in the wheat genome, which were classified into four subfamilies. Collinear analysis indicated that fragment duplication plays an important role in the amplification of the wheat GATA gene family. Functional disproportionation analysis between subfamilies found that both type I and type II functional divergence simultaneously occurs in wheat GATA genes, which might result in functional differentiation of the TaGATA gene family. Transcriptional expression analysis showed that TaGATA genes generally have a high expression level in leaves and in response to drought and salt stresses. Overexpression of TaGATA62 and TaGATA73 genes significantly enhanced the drought and salt tolerance of yeast and Arabidopsis. Protein–protein docking indicated that TaGATAs can enhance drought and salt tolerance by interacting between the DNA-binding motif of GATA transcription factors and photomorphogenesis-related protein TaCOP9-5A. Our results provided a base for further understanding the molecular evolution and functional characterization of the plant GATA gene family in response to abiotic stresses.

Spelt wheat (Triticum spelta L., 2n=6x=42, AABBDD) is a valuable source of new gene resources for wheat genetic improvement. In the present study, two novel high molecular weight glutenin subunits (HMW-GS) 1Ax2.1* at Glu-A1 and 1By19* at Glu-B1 from German spelt wheat were identified. The encoding genes of both subunits were amplified and cloned by allele-specific PCR (AS-PCR), and the complete sequences of open reading frames (ORF) were obtained. 1Ax2.1* with 2478 bp and 1By19* with 2163 bp encoded 824 and 720 amino acid residues, respectively. Molecular characterization showed that both subunits had a longer repetitive region, and high percentage of α-helices at the N- and C-termini, which are beneficial for forming superior gluten macropolymers. Protein modelling by AlphaFold2 revealed similar three-diamensional (3D) structure features of 1Ax2.1* with two x-type superior quality subunits (1Ax1 and 1Ax2*) and 1By19* with four y-type superior quality subunits (1By16, 1By9, 1By8 and 1By18). Four cysteine residues in the three x-type subunits (1Ax2.1*, 1Ax1 and 1Ax2*) and the cysteine in intermediate repeat region of y-type subunits were not expected to participate in intramolecular disulfide bond formation, but these cysteines might form intermolecular disulfide bonds with other glutenins and gliadins to enhance gluten macropolymer formation. The SNP-based molecular markers for 1Ax2.1* and 1By19* genes were developed, which were verified in different F2 populations and recombination inbred lines (RILs) derived from crossing between spelt wheat and bread wheat cultivars. This study provides data on new glutenin genes and molecular markers for wheat quality improvement.

Supercapacitors (SCs) have attracted many attentions and already became part of some high-power derived devices such as Tesla’s electric cars because of their higher power density. Among all types of electrical energy storage devices, battery-supercapacitors are the most promising for superior performance characteristics, including short charging time, high power density, safety, easy fabrication procedures, and long operational life. An SC usually consists of two foremost components, namely electrode materials, and electrolyte. The selection of appropriate electrode materials with rational nanostructured designs have resulted in improved electrochemical properties for high performance and has reduced the cost of SCs. In this review, we mainly spotlight the nickel-based selenides nanostructured which applied as high-performance cathode materials for SCs. Different nickel-based selenides materials are highlighted in various categories, such as nickel-cobalt-based bimetallic chalcogenides and nickel-M based selenides. Also, we mentioned material modification for this material type. Finally, the designing strategy and future improvements on nickel-based selenides materials for the application of SCs are also discussed.

A novel analytical model is proposed and validated in this paper to predict the velocity deficit in the wake downwind of a wind turbine. The model is derived by employing mass and momentum conservation and assuming a cosine-shaped distribution for the velocity deficit. In this model, a modified wake growth rate rather than a constant one is chosen to take into account the effects of the ambient turbulence and the mechanical turbulence generated. The model was tested against field observations, wind-tunnel measurements in different thrust operations and high-resolution large-eddy simulations (LES) for two aerodynamic roughness lengths. It was found that the normalized velocity deficit predicted by the proposed model shows good agreement with experimental and numerical data in terms of shape and magnitude in the far wake region ( x / d 0 > 3 ). Based on the proposed model, predictions from multiple views and at different locations are demonstrated to show the spatial distribution of streamwise velocity downwind of a wind turbine. The result shows that the model is suitable for predicting streamwise velocity fields and thus could provide some references for the selection of wind turbine spacing.