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Graphene possesses a unique two-dimensional structure， a high specific surface area， excellent electrical conductivity， and controllable surface functional groups， and its use in advanced oxidation has received extensive attention. Graphene-based materials can effectively activate oxidants to generate reactive oxygen species （ROS）， and efficiently degrade organic pollutants， thereby compensating for the shortcomings of traditional water treatment technologies. The number of publications on graphene-based materials and advanced oxidation technologies has increased rapidly， but systematic summaries of these research results are lacking. In order to comprehensively reveal the research hotspots and development trends in this field， the visualization software CiteSpace was used to conduct a bibliometric analysis of 912 relevant papers published in the Web of Science Core Collection from May 2015 to April 2025. The research hotspots in this field were discussed， the main existing problems were summarized， and future research directions were predicted. The results show that the distribution of countries and regions involved in research in this field is quite extensive globally. China has the largest number of publications， accounting for 62.2% of the total. Cooperation between countries or regions is relatively extensive， but cooperation between different research institutions and teams is insufficient. The main research hotspots of graphene-based materials in advanced oxidation technology are graphene modification， degradation of emerging pollutants， and advanced oxidation mechanisms. The main problems in this field lie in the preparation of graphene-based materials and their impact on the environment， as well as in research on advanced oxidation mechanisms and their engineering applications. The results presented in this article can serve as a reference for researchers in related fields to analyze existing research outcomes， understand current research trends， and grasp future development directions.
Phosphorus is an essential nutrient for the growth of all living organisms. However， the improper discharge of phosphorus is also a key factor contributing to water eutrophication. With increasingly stringent phosphate emission limits and the sustained demand for phosphorus resources， the adsorption and recovery of phosphorus， followed by the high-value utilization of its products， represents a crucial future direction in this field. Adsorbents are key to achieving this goal. In recent years， magnesium-based adsorption materials have been widely studied due to their high affinity for phosphate， cost-effectiveness， and environmental friendliness. This paper reviews current research progress on phosphate removal performance， adsorption mechanisms， and the factors influencing phosphorus removal by magnesium-based functional materials. It provides an in-depth discussion of the material modification strategies for magnesium oxide， magnesium hydroxide， and various carrier-supported magnesium-based materials. Furthermore， the resource utilization methods for the recovery of adsorbed phosphate are analyzed. The phosphate adsorbed on the material can be recovered through elution， and the products after phosphorus adsorption can also be used for soil improvement， soil remediation， and water environment restoration. The applicable conditions for these resource utilization methods are analyzed， and the future research directions for subsequent phosphorus removal by adsorption are clarified. This work provides a reference for future research on phosphate removal by magnesium-based materials and phosphorus resource utilization.
In light of the rapid economic growth and accelerated urbanization in China， the quality standards for construction engineering have been continuously raised. The durability of architectural waterproof coatings is essential for the longevity and safety of buildings. Their performance is critical not only for engineering quality and user experience but also profoundly impacts for the high-quality development of China’s construction industry. Integrated decorative waterproof coatings effectively address issues inherent in traditional multi-layer waterproof systems， such as complex construction procedures and the risk of interlayer detachment. This article systematically reviews recent advances and development trends for integrated decorative waterproof coatings， analyzes the strengths and limitations of silicone rubber-based coatings， polymer cement-based coatings and stone-like coatings， and highlights current application status and future development trends for these coating systems. In addition， the article summarizes the construction procedures and key technical considerations for integrated decorative waterproof coatings in practical applications， offering a viable pathway for the low-carbon development and green transformation of the building waterproofing sector.
Taking the waste tire pyrolysis process of a typical enterprise as a practical case， the fire and explosion characteristics of carbon black in both dust layer and dust cloud forms were analyzed. The results show that the minimum ignition temperature of the dust layer exceeds 400 °C. If the dust layer comes into contact with a fire source under certain conditions， there is a potential fire risk. The minimum ignition temperature of the dust cloud is 620 °C， and the particle size distribution is in the ultra-fine dust region. In the case of a carbon black dust cloud， the risk of fire and explosion is relatively high. Hazard and operability analysis （HAZOP） identified 12 risk scenarios in the carbon black post-treatment system （75% of which were level I risks） and 8 potential leakage sources. Additionally， fire and explosion accident scenarios were constructed for carbon black dust leakage under various conditions. Based on the integrated safety management concept of “five flows–three transformations–three controls”， at the levels where “material flow” and “energy flow” are not out of control and “control flow” is error-free， several accident prevention and mitigation measures have been proposed. These include controlling the concentration of carbon black dust， enhancing the sealing performance of production equipment， formulating emergency plans for dust explosions， and installing real-time monitoring instruments for combustible dust. These results can provide a theoretical basis and feasible suggestions for the safety management of carbon black deep processing in waste tire pyrolysis.
Industrial organic wastewater has become a major challenge in water pollution control due to its complex composition， high biological toxicity， and refractory biodegradability. Traditional wastewater treatment processes exhibit low efficiency， and single advanced oxidation technologies also present obvious bottlenecks， failing to meet the demand for efficient treatment of complex wastewater. Therefore， the ozone-electro-Fenton coupling process was employed to treat simulated wastewater containing methyl orange or malachite green， and its performance was compared with those of the single ozone process and the single electro-Fenton process. The experimental results show that under the optimal conditions of an ozone generation rate of 1.8 g/h， ozone/air mixed gas flow rate of 500 L/h， and current of 100 mA， after 40 minutes of treatment with the ozone–electro-Fenton coupling process， the decolorization rate of methyl orange reached 94.4% and that of malachite green reached 99.6%， superior to the corresponding values for the single ozone process or the single electro-Fenton process. The results indicate that the coupling process overcomes the bottleneck in single oxidation technologies by synergistically enhancing performance， providing a practical technical solution for the efficient treatment of refractory organic wastewater.
Spin flash drying is a crucial step in the preparation of molecular sieves. The gas-solid two-phase flow in the drying tower is an important factor affecting the drying efficiency and product quality. Using the discrete phase model （DPM）， the gas-solid two-phase flow and distribution inside a spin flash drying tower were calculated by numerical simulation methods. The influence of different operating parameters on the gas–solid two-phase flow and particle residence time in the drying tower was analyzed. The results show that the particles in the drying tower exhibit a distinct swirling motion. The particle distribution is uneven with a dense edge and a sparse center. Increasing the operating gas velocity can significantly increase the gas flow rate in the drying tower and reduce the average particle residence time. The influence of the spray angle of the atomizer on the average residence time is generally not significant. However， if the spray angle is too large， particles may come into contact with the dry tower wall prematurely， resulting in scaling on the inner wall. The influence of the spray height on the average particle residence time is also relatively small. However， if the spray height is too low， particles are likely to accumulate at the bottom of the drying tower， which will affect product quality.
Transparent rigid polyurethanes with different hard segment （HS） contents were prepared using 4，4'⁃dicyclohexylmethane diisocyanate， polytetrahydrofuran polyether， high hydroxyl-value polyether polyol， and trimethylolpropane as raw materials. The mechanical properties， optical and dynamic mechanical properties， and the thermal resistance of the transparent rigid polyurethanes with different HS contents were studied using an electronic universal testing machine， a hardness tester， a light transmittance and haze tester， a dynamic mechanical analyzer， and a thermogravimetric analyzer， respectively. The results showed that as the HS content increased， the tensile strength and hardness of the polyurethane gradually increased. The maximum tensile strength reached 62.0 MPa and the Shore D hardness at 20 ℃ had a maximum value of 84. The visible light transmittance ranged from 91.06% to 92.08%， and the haze ranged from 1.62% to 1.71%. The glass transition temperature increased gradually， reaching a maximum value of 92.5 ℃. The temperature range with tan δ ≥ 0.5 shifted toward higher temperatures and broadened. The temperature at 5% weight loss exhibited an initial decreasing trend followed by an increase， reaching a minimum of 286.6 ℃. As the HS content increased from 80% to 85%， the thermal decomposition process of the HS shifted from two stages to a single one.
Hyperbranched waterborne polyurethanes （HWPUs） with different APTES contents were prepared using polycarbonate diol （PCDL）， isophorone diisocyanate （IPDI）， hyperbranched polyester polyol （HBP） and 3⁃aminopropyltriethoxysilane （APTES）. The effect of varying the APTES contents on the surface， emulsion and mechanical properties， as well as on the water resistance and heat resistance of HWPU were investigated. The results showed that when the amount of APTES concentration was 3%， the average particle size of HWPU was 68.2 nm， the tensile strength was 46.5 MPa， and the elongation at break was 432%. The tensile strength was still greater than 30 MPa after 24 h of immersion in water. The initial thermal decomposition temperature exceeded 270 ℃.This work offers a new strategy for the developing of water-based ink for fabric inkjet printing.
This study addressed the critical challenges of a low expansion ratio， a narrow foaming temperature window， and severe shrinkage in polyether block amide （PEBA） foams which are caused by the linear molecular structure and inadequate melt viscoelasticity. By synergistically combining epoxy-based chain extension modification （KL-E4370B） and nitrogen （N2）-assisted gas exchange， enhanced melt viscoelasticity has been achieved through increased molecular branching （evidenced by an order of magnitude higher complex viscosity and elevated storage modulus） alongside effective shrinkage mitigation. The modified PEBA exhibits a remarkable 34.25% improvement in expansion ratio and a 65 ℃ broadening of the foaming temperature window. For the 2wt% KL-E4370B modified system， while CO2 foaming initially produced a 22.75 expansion ratio that shrank to 5.52 （with partial recovery to 6.91）， the N2-assisted protocol achieved a peak expansion ratio of 36.58 with post-shrinkage retention at 25.64，surpassing the original CO2 performance. Microstructural analysis reveals that the nitrogen exchange not only counteracts shrinkage through gas replacement but also promotes secondary cell growth via the formation of thinner cell walls during N2 foaming. This dual strategy enables rapid fabrication of high-expansion， dimensionally stable PEBA foams， providing an innovative solution to persistent shrinkage issues in thermoplastic elastomer foams and significant industrial potential.
With the widespread development of pumped storage power station planning and construction， the winter operation of existing high cold area face rockfill dams is significantly affected by ice damage， leading to problems such as easy detachment after long-term immersion， delamination due to frost heaving， and damage from ice pushing and ice scraping of traditional surface protective materials for panels. To meet the performance requirements of surface protective materials for panels in cold regions， a fluorine-modified polyurethane surface anti-icing material has been prepared using the fluorine-terminated agent 1H， 1H， 2H， 2H-perfluorooctanol. The ice adhesion strength， mechanical properties， and water resistance of the materials were experimentally demonstrated. After a winter on-site engineering verification of the 1#~2# panels on the left bank of the upper reservoir dam at a pumped storage power station in a severe cold region， the material did not exhibit long-term immersion or delamination and showed good anti-seepage and anti-icing performance. These results represent a breakthrough in surface waterproofing and anti-icing technology for concrete face rockfill dams in high cold regions.
When using traditional autonomous navigation methods with wheeled unmanned vehicles， the algorithms do not fully account for non⁃complete constraint properties and steering geometry limitations. This often leads to untraceable trajectories， preventing the vehicle from completing the expected navigation tasks. In this work， a new autonomous navigation method has been designed based on the Robot Operating System （ROS） modularization， which employs the Cartographer algorithm based on graph optimization to achieve the functions of map building and localization， and incorporates SBPL_Planner and Lattice_Planner based on the search-based planning library （SBPL）. Lattice_Planner together with TEB_Local_Planner based on time elastic band （TEB） planning library，are used for global and local path planning respectively， thereby faciliating autonomous navigation of the vehicle. Test experiments were conducted， and the kinematic characteristics of the vehicle were compared with those of traditional autonomous navigation methods. The results show that our autonomous navigation method can plan a path that meets the kinematic characteristics of the vehicle， effectively responds to situations such as sudden obstacles and narrow spaces， and meets the requirements for the use of intelligent wheeled unmanned vehicles for autonomous navigation functions.
An adaptive feedforward controller has been developed to address the impact on flight stability of variations in the moment of inertia caused by mechanical leg movements during the flight of amphibious unmanned aerial vehicles （UAVs）. Firstly， a dynamic model of a hexacopter UAV was established. Based on the variable range of the motion angles of the mechanical legs， the variation interval of the moment of inertia was determined， and a set of mechanical leg motion paths covering the maximum， minimum and extreme variation values of moment of inertia was designed. This converts the relationship between the moment of inertia and the time into a nonlinear function. Furthermore， given the variable moment of inertia of amphibious UAVs， a control strategy based on feedforward control was developed. Finally， a simulation in Simulink was carried out to compare feedforward control with the traditional proportional-integral-derivative （PID） control under the conditions of a dynamically changing moment of inertia. The results verified the superior performance of our feedforward controller in dealing with variations in the moment of inertia of amphibious UAVs.
To investigate the effects of the diameter ratio on the mixing process and the thermal fluctuations of hot and cold fluids in a T⁃junction， an experimental setup was constructed that simultaneously measuring the temperatures of the outer wall surface， the near inner wall surface， and the fluid. Experiments were conducted for diameter ratios （D m/D b） of 1 and 2.5， corresponding to impinging jet and deflecting jet flow types， respectively， and the temperature data were normalized for analysis. The experimental results indicate that when the change in pipe diameter ratio alters the momentum ratio and thereby affects the flow type， impinging jets exhibit more pronounced thermal stratification and greater temperature fluctuations than deflecting jets. Power spectral density （PSD） analysis reveals that due to the thermal capacitance of the pipe wall， the main frequency of the wall energy shifts to a lower frequency than that of the fluid. Additionally， the PSD of both the pipe wall and the fluid in deflecting jets is generally lower than the corresponding values in impinging jets. Therefore， when the flow type in the T-junction is an impinging jet， reducing the branch diameter can effectively decrease thermal fluctuations in the pipeline， thereby preventing thermal fatigue failure.
This work proposes algorithm based on MobileNetV3 to address the challenges of decreasing localization accuracy and increasing cumulative errors in traditional visual simultaneous localization and mapping （SLAM） loop closure detection algorithms in complex environments such as illumination variations， dynamic scenes， and viewpoint changes. A pretrained MobileNetV3 model is utilized to extract robust image features， followed by principal component analysis （PCA） and whitening to reduce the dimensionality of feature vectors and improve computational efficiency. Cosine similarity is employed to compute a similarity matrix of image features， and loop closures are identified based on predefined thresholds. Experimental results demonstrated that our MobileNetV3-based algorithm outperformed several comparative methods. Compared with the Bag-of-Visual-Words （BOVW） based approach， when using the New College and City Centre datasets our method achieved improvements in detection accuracy of 18.5 %and 19.3%， and enhanced detection speed of 30.6% and 34.4%， respectively. These results meet the accuracy and real-time performance requirements of visual SLAM systems. Furthermore， the algorithm was integrated into ORB-SLAM2 by replacing its original BOVW loop closure module. Evaluations using the EuRoC dataset showed that the enhanced ORB-SLAM2 achieved a 23.8% improvement in localization accuracy， with the estimated trajectories significantly closer to the Ground Truth. These results validate the feasibility and effectiveness of our algorithm for use within SLAM systems.
We studied the convergence of the truncated Euler method for one⁃dimensional non⁃autonomous stochastic differential equations with a Hölder continuous diffusion term and obtained its convergence using the Yamada⁃Watanabe approximation. Compared with earlier work， the main innovation in this paper is to change the type of equation to a non⁃autonomous stochastic differential equation by introducing a time variable “t”， and make both the diffusion term and drift term Hölder continuous with respect to the time variable “t”. We obtained the convergence rate， and proved that it is dependent on the Hölder order of “t”. Finally， a numerical example is given to illustrate the conclusion.
This paper concerns a scalable model⁃averaging method with right⁃censored responses. By using inverse probability censoring weighting to synthesize new responses and a singular value decomposition to transform the original models， this method enables us to estimate the weights by considering maximum of p covariate models. The Mallows criterion and the Jackknife criterion are applied to the selection of weights without the standard constraint that the weights sum to one. The theoretical results show that the calculated weights exhibit asymptotic optimality in the sense of achieving the lowest possible least squares error. Numerical studies demonstrate the excellent averaging performance of the proposed model in terms of both predictive accuracy and computational time.
