Abstract: In China, the reserves of platinum group metals (PGMs) are scarce, but the consumption of PGMs is enormous, which has resulted in a high external dependence. As more than 90% of PGMs are used by the catalyst industry, spent catalysts are the most important secondary source. Therefore, recycling PGMs from spent catalysts is the most significant strategy for relieving the risk of shortage in the PGMs supply. In this review, the consumption distribution of PGMs and their recycling status were introduced and recycling technologies were discussed in detail. The volume of recycled PGMs has been estimated to be approximately 20%–30% of the global mine production and this trend is increasing. Sample analysis is considered to be crucial for determining the recovery efficiency of PGMs. Extensive studies have shown that pretreatment methods such as reduction, calcination, and mechanical milling can improve the efficiency of PGMs recovery. Compared with traditional cyanide leaching and aqua regia dissolution, more environmentally friendly leaching methods have been developed in recent years, including chlorination leaching, supercritical fluids extraction, and substrates leaching. However, although some hydrometallurgical processes have been industrialized, their disadvantages include the generation of wastewater, emission of hazardous gases, and low recovery efficiency of Rh, which must be carefully evaluated. Pyrometallurgical methods have been widely used to concentrate PGMs due to the generally low PGMs content in spent catalysts. Lead, copper, iron, and matte are good PGMs collectors, whereby the PGMs form alloys with the collector metals and supporting materials, then enter the slag phase. These melting collection methods were reviewed and their advantages and disadvantages were summarized. Based on the serious environmental problems and low recovery efficiency of PGMs by current technologies, future trends for PGMs recycling have been proposed, including activation pretreatments, co-recovery of valuable metals and carrier materials, base metals synergistic smelting, iron melting capture, and electrolysis. These recycling technologies may indicate the development directions and can serve as effective references for further research in this field.
Abstract: The overuse of resources and the frequent occurrence of environmental problems have necessitated the use of sustainable energy technologies. The microbial fuel cell (MFC) is a kind of green energy-generation technology that metabolizes the organic compounds in wastewater by the catalytic oxidation of microorganisms. This new technology provides the dual advantages of cleaning the environment and generating electricity. As MFCs can potentially convert biodegradable and recyclable wastes into clean energy, they are a promising application prospect in environmental treatment and energy utilization. However, the practical applicability of present-day MFCs is limited by their low power-generation efficiency. Anode electrodes can enrich the power generation and electron transfer of microorganisms, but require high polarization, electronic conductivity, and biological compatibility with the fuel cell. Broadly speaking, the anode electrode affects the performance and operating costs of an MFC. Commonly used carbon-based materials include graphite sheets, carbon cloths, carbon paper, and carbon felt. However, most of these materials are two-dimensional structures providing few attachment sites for microorganisms; other materials have few reactive sites, which limits their electrochemical reactive surface areas and slows the initiation of the MFC. Carbon nanomaterials have been extensively researched for their high electrical conductivity, large specific surface area, high porosity, and low cost. All of these properties are demanded in the anode materials of MFCs. This paper summarized and analyzed methods for improving the biological compatibility of electrodes, increasing the adhesion of electrically-producing microorganisms, and improving the reactive activation sites. To this end, it discussed various types of anode electrodes, electrode structure designs, and electrode material modifications. A mechanism that improved the electricity generation performance was also discussed. Finally, carbon-based electrode materials might provide theoretical guidance for preparing anode materials with high electrochemical activity.
Abstract: With the continuous consumption of fossil fuels, the increasingly serious problem of environmental pollution and increasing demand for electricity in China have forced the need to gradually increase the capacity of renewable energy technologies such as wind and photovoltaic power. The randomness and intermittence associated with in the generation of wind and photovoltaic power bring new challenges to the safety and stability of power-grid operations. With respect to the generation of either stationary or distributed power, the solid oxide fuel cell (SOFC) power-generation system can be designed according to the actual demands of specific users and effectively supplement shortages in the generation of centralized power, and thereby significantly improve the efficiency, reliability, and stability of the power supply. SOFCs have many advantages, including fuel flexibility, high energy-conversion efficiency (power-generation efficiency ranging of 40%–60%, comprehensive energy efficiency ≥80%), a whole solid structure, modular assembly, and near-zero pollution. SOFCs have a variety of different structures, and their power-generation scales range from tens of watts to hundreds of megawatts, with different structures selected for different application scenarios. These application scenarios mainly include fixed power generation, distributed power supply, combined heat (cold) and power supply, and auxiliary power units for traffic vehicles. SOFC technology in China has developed more recently than that in foreign countries and has made some progress. Manufacturers in China can independently develop SOFC power generation systems that produce more than 10 kW of power, but there remains a big gap between the systems developed in China and those developed by SOFC technology leaders elsewhere in the world, which is mainly reflected in the output power, production cost, and durability. Europe's SOFC technology is at the forefront, with a number of successful companies having realized effective products. Through the investigation of their technology and products, we can gain an in-depth understanding of the current situation and development trends of SOFC technology as a reference for improving China’s SOFC technology.
Abstract: Metal-organic frameworks (MOFs) are a class of organic–inorganic hybrid functional materials that are generally formed via the self-assembly of metal ions or metal clusters and rigid organic ligands with nitrogen and oxygen atoms. A wide range of potential applications for MOF materials includes gas storage and separation, catalysis, sensing, and drug transportation and release, which is attributable to their versatile designable structures, modifiable chemical functionality, low-density frameworks, large specific surface areas, and functional and permanent pore space. In the past decade, MOFs and their composite materials have also been employed to remove various contaminants from the environment. This paper presented the significant research progress and outcomes achieved using MOF materials in the removal of environmental pollutants from water, based on a review of related studies regarding the removal of heavy metals and organic pollutants from water environments. This represented the first part of a larger paper in which the progress of MOF materials research was presented with respect to the removal of heavy metals from aqueous solution. The presence of heavy metals in water is a global environmental issue that has been receiving considerable attention worldwide. According to previous research reports, MOF materials have high adsorption capacities for common heavy metals, such as Pb2+, Cu2+, Cd2+, Co2+, Ag+, Cs+, Sr2+, Hg(II), $ {\rm{TcO}}_4^ - $, Se(VI), As(III), and As(V). Some MOF materials have even higher adsorption capacities than conventional adsorbent materials. The adsorption mechanism mainly involves electrostatic attraction, coordination/chelation, ion exchange, and pore adsorption (physical adsorption). Based on a review of previous studies, it is believed that the future research field includes but is not limited to the following: (1) the structure–activity relationship between the MOF structure and heavy-metal removal, (2) the functionalization, surface modification, and pore size adjustment technology of MOF, or the preparation of composite MOF materials, (3) further study of the regulation of the defect structures of MOFs to develop new MOF materials with higher adsorption efficiency, (4) improving the recyclability of MOF materials, and (5) developing new MOF materials with high structural stability, high adsorption capacities, high selectivity, low cost, and which are easily reused.
Abstract: Phytoremediation is an important means of soil heavy metal pollution remediation. In order to figure out the soil pollution status of the water source in the middle line of the South-to-North Water Transfer Project and repair it, soil samples (n = 14) and local dominant terrestrial plants (n = 113) were collected in typical areas around Chaobei River and the typical vanadium smelter in Hubei Province in four seasons. Microwave digestion–inductively coupled plasma mass spectrometry (ICP?MS) was applied to analyze the concentrations of vanadium (V), chromium (Cr), arsenic (As), and cadmium (Cd) in soils and plants. Soil pollution levels were evaluated on the basis of the Nemerow index method. The enrichment capabilities of plants for the four heavy metals were also analyzed. Results show that the heavy metal content of soil around the junction of the sewage outfall and the river is the highest among the seven sampling sites around Chaobei River. The concentration of V in the raw ore stacking area exceeds the limit by approximately 83 times and the concentrations of Cr, As, and Cd exceed the limit by approximately 2 times, which make the soil in the raw ore stacking area heavily contaminated. The soils in the six other sampling sites in the smelter are polluted in different degrees. The results of the evaluation of the enrichment and tolerance capabilities indicate that Gnaphalium affine, Erigeron multifolius, and Erigeron annuus have the highest tolerance capability for the four heavy metals. Conyza canadensis, Imperata cylindrica, Solanum photeinocarpum, Dendranthema indicum, Trifolium repens, and Echinochloa crusgalli are the hyperaccumulators for V, Cr, and Cd. The enrichment capabilities of Pteris vittata and Broussonetia papyrifera for As are extremely high. Moreover, Artemisia lavandulaefolia has a high enrichment capability for Cr and Cd, Ludwigia prostrata and Picris japonica have prominent tolerance and enrichment specificities for Cr and V, and Potentilla chinensis and Phytolacca americana have obvious enrichment capabilities for Cd specifically. The pot experiments of five local dominant terrestrial plants illustrate that, under the composite heavy metal contaminant conditions, Boehmeria nivea has the highest tolerance capability and Potentilla chinensis has the highest enrichment capability.
Abstract: In 2017, China's industrial dust emissions accounted for 7.96 million tons, of which the iron and steel industry contributed approximately 25%. Particulate matter discharged from the iron and steel industry is mostly of a small size, high in temperature, and complex in composition. The mass concentration of ultrafine particles (UFPs) with particle sizes that are less than 0.1 μm is low; however, the proportion of quantity concentration can be as high as 90%. Currently, the commonly used bag filters and electrostatic precipitators are not sufficiently efficient at collecting fine particles. Additionally, owing to the larger specific surface area of fine dust particles, they easily become carriers of adsorbing harmful gases, which has a greater impact on the environment and human health; thus, it is imperative to determine a simple and efficient filtration method to remove ultrafine particles. In this paper, the removal efficiency and mechanism of UFPs (2.5–25 nm) were investigated by using a scanning electromobility particle size spectrometer (SMPS) test system for SBA-15 for different pore sizes. This was done to provide a theoretical basis for the application of mesoporous materials in the control of ultra-low emission of particulate matter in the iron and steel industry. Based on the experimental results and characterization analysis, it is found that a mesoporous filtration medium with a large pore size is more efficient at affecting UFPs entry. There are many affinity sites for UFPs on the inner and outer surfaces of mesoporous materials with a specific pore size. Increasing the complexity of the ends is beneficial for improve the filtration performance of the materials. The presence or absence of nitrogen has little effect on the removal of UFPs. The diffusion effect of UFPs is stronger owing to the existence of mesoporous particles, and the diffusion coefficient is increased when particles enter the pore. Therefore, there is a difference between the theoretical exponent (m= ?2/3) in the traditional model for particle diffusion and the actual diffusion results of UFPs in mesoporous materials.
Abstract: One of the most effective methods for the removal of NOz from industrial flue gas is the technology known as low-temperature selective catalytic reduction (SCR). The main problem limiting the industrial application of catalysts is the need to improve their performances at low temperatures, and the fact that the anti-toxic mechanism of low-temperature denitration catalysts has yet to be explicitly identified. In this study, a TiO2?ZrO2?CeO2 (molar ratio 4∶1∶1.25) carrier was prepared by the sol–gel method, and then loaded the active components MnOx and MnOx?FeOy using the citric-acid-solution impregnation method to synthesize a new type of Fe-modified Mn-based multi-oxidation-state composite catalyst. The performance of this Mn-based composite oxide catalyst was investigated with respect to its NH3-selective catalytic reduction of NO and sulfur resistance. The catalyst exhibits good low-temperature SCR redox ability and anti-poisoning ability in an SO2-containing atmosphere, whereby the introduction of Fe promotes the interaction between Mn and the TiO2?ZrO2?CeO2 (4∶1∶1.25) carrier, and increases the number of Lewis acid sites on the catalyst surface. According to the XPS analysis, the contents of Mn4+, Ce4+, and adsorbed oxygen are obviously increased, which is very advantageous for improving the performance of the catalyst. According to the thermogravimetric analysis, the introduction of Fe reduces the production of ammonium sulfate and ceric sulfate in the atmosphere containing SO2 and H2O, and inhibites the sulfation of manganese. The Fe element thereby increases the anti-toxic ability of the Mn-based multi-oxidation-state composite catalyst. By maintaining the MnOx (12.5%)?FeOy(0.8)/TiO2?ZrO2?CeO2 (4∶1∶1.25) catalyst at 180 ℃, while continuously feeding 10% H2O in volume fraction and 125×10?6 SO2 for 240 min, the NOz conversion rate can be stably maintained at 75.6%. Based on the results of this work, a new type of Mn-based composite oxide catalyst has been developed that provides a foundation for further exploring the SCR reaction of the catalyst and its anti-toxic mechanism to promote the industrial application of the SCR process.
Abstract: The Ruhrstahl Heraeus (RH) refining furnace is a piece of important secondary refining equipment that is widely used in the production of special steel owing to its high efficiency of degassing, decarburization, and de-intercalation. However, molten steel that has a high alloy content will encounter key problems in the vacuum treatment process, and the loss of volatile alloying elements in the molten steel is considerable, resulting in the nodulation of the molten steel vacuum splashing and secondary oxidation of the subsequent molten steel. To address the problems of elemental loss and vacuum splashing caused by manganese (Mn) gasification during the vacuum processing of manganese-containing steel using RH, the variation and migration behavior of Mn in molten steel under different vacuum treatment conditions of 120 t RH were examined. This study analyzed the relationship between manganese elemental loss and its volatilization and vacuum splattering, and it was verified in an anatomical experiment of the nodule at different positions inside the RH vacuum chamber. The results show that elemental Mn in the molten steel shows obvious loss during the vacuum process of RH, and the loss in the early stage of the vacuum process is the largest. The composition of manganese oxide in the nodule of the RH vacuum chamber is as high as 14%–70%, and the thermodynamic calculation results show that temperature, the content of Mn in the steel, and the degree of vacuum have a considerable influence on the volatilization behavior of Mn, which is the key influencing factor for manganese migration during the vacuum process. By improving the vacuum pressure drop mode, a stepwise vacuum is used to reduce the loss of elemental Mn from the original 2×10?4 to 1×10?4. The results have considerable significance for on-site production, and steel can be effectively restrained by improving the vacuum pressure drop mode. Additionally, the splashing and volatilization of liquid reduces the loss of the alloying element Mn.
Abstract: The addition of certain amounts of Mn in steel has long been known to retard the growth and coarsening of cementite during tempering, which can increase the tempering resistance of carbon steels. It is now well-established that the retarding effect is inherently correlated with the partitioning of Mn between ferrite (α) matrix and cementite (θ). According to the equilibrium thermodynamics, Mn would diffuse from α-Fe matrix to θ cementite after the initial stage of tempering until equilibrium is reached. However, the manner in which Mn diffuses from α-Fe matrix to θ cementite is unclear, which is key in understanding the mechanism in which the partitioning of Mn can retard the growth and coarsening of cementite. Therefore, the measurement of Mn content across the α-Fe/θ interface is of importance to achieve this goal. In this study, the redistribution characteristics of Mn between α-Fe matrix and θ cementite after long-term aging at 370 or 400 °C with quenched–tempered or quenched samples of reactor pressure vessel model steel was investigated by atom probe tomography. Results show that Mn diffuses from the α-Fe matrix and enriches in the θ cementite under all heat treatment conditions. The concentration of Mn in cementite is the highest when the specimen is thermally aged directly after quenching. Moreover, Mn is not distributed uniformly within cementite after long-term aging at 400 °C for 35000 h. Instead, a Mn-segregated zone exists within cementite adjacent to the α-Fe/θ interface, with concentration increasing by aging temperature, which acts as a barrier to the coarsening of cementite by hindering the dissolution of small-sized cementite. The redistribution characteristics of Mn between the two phases is correlated with the difference of diffusivities in the α-Fe matrix and θ cementite during thermal aging, and the diffusivity of Mn in θ cementite is slower than that in α-Fe matrix.
Abstract: As the core component of continuous casting machines, complex behaviors of fluid flow, heat transfer, mass transfer, and solidification occurring inside the mold are the key factors affecting the slabs quality. Breakout is one of the most catastrophic accidents in continuous casting process, which brings severe impacts on personal security, smooth producing, slab quality, and caster equipment. In particular, with the development of the high-speed casting technology, quality defects and sticking breakouts caused by high-load emerge frequently and missing or false alarms for online prediction of breakout occasionally occur. Thus, accurate identification and prediction for the mold breakout is a top priority for online processing control. Considering the typical temperature characteristics of “time lag” and “space inversion” during a breakout, this paper introduced the concepts of dynamic time warping (DTW) and density-based spatial clustering of applications with noise (DBSCAN) in machine learning. On the basis of collecting and distinguishing the typical change modes of mold temperature, an integrated novel method for predicting breakout was developed. The proposed method applied DTW to measure the similarity of mold thermocouple temperature under different casting speeds, steel grades, and other operating conditions, while DBSCAN was used to cluster and separate the temperature samples between normal casting status and sticking breakout. On the basis of the above mentioned method, the results show that the mold sticking breakout can be effectively detected and predicted. Compared with the traditional method based on logical judgment and artificial neural network, the clustering-based breakout prediction method does not require manual setting of thresholds or parameters. According to the common rule of temperature variation in historical samples of breakout, the typical characteristics of temperature in time and space can be extracted and fused, and the breakout can be accurately distinguished and predicted, which shows good self-adaptability and robustness.
Abstract: Miniaturized batteries are widely utilized in microscale devices, and 3D printing technology has great advantages in the manufacture of miniaturized battery electrodes. Lithium–nickel–cobalt–manganate material (LiNi0.5Co0.2Mn0.3O2) is gradually becoming a mainstream cathode material for lithium-ion batteries due to its high energy density, high rate of performance, high stability, and low cost. In this study, we prepared lithium-ion-battery electrodes using extrusion-based three-dimensional (3D) printing technology, and we selected ternary nickel–cobalt–manganese hydride as the positive active material. Subsequently, using deionized water, hydroxyethyl cellulose, and other additives, positive inks was prepared for the lithium-ion battery that exhibited stable performance and adequate 3D printing. The effects of thickener type and content, ink viscosity, and the printing process on the rheological properties and printability of the ink were investigated using a rheometer, X-ray diffraction, a battery tester, and ANSYS simulation analysis. The results show that when the mass ratio of hydroxyethyl cellulose/hydroxypropyl cellulose is 1∶1 and the mass fraction is 3%, the viscosity of the prepared ink is 20.26 Pa·s, and it shows good rheology and uniformity in printing. At present, the printing electrode has good rheology, steady ink outflow, and a smooth surface, which satisfies the printability requirements of the ink. Additionally, the simulation results show that the fluidity of the ink is significantly influenced by its viscosity. The electrode preparation process, e.g., ultrasonic dispersion, printing, or sintering, does not lead to a change in the crystal structure of the electrode material. The first-charge and discharge capacities of the electrodes are 226.5 and 119.4 mA·h·g?1, respectively. After 20 cycles, the change rates of the charge and discharge capacities in the battery decrease and then tend to become stable. Lastly, the 3D printed electrode exhibits good cycle stability.
Abstract: The continuous improvement of people’s living standards and quality puts higher and higher demands on polymer materials, and damping materials such as polyurethane elastomer used for vibration and noise reduction have also received increasing attention. However, the application of polyurethanes is limited to some extent owing to the narrow effective damping temperature range of polyurethane. Therefore, polyurethane containing a branched chain has been prepared from the perspective of its structural designability, in which the prepolymer synthesized by the reaction of polyethylene glycol monomethyl ether (MPEG) with toluene 2,4-diisocyanate (TDI) is performed as a branched chain. Herein, the long branched chain with one end fixed at the end gives its unique movement and relaxation, contributing to the superior damping performance of polyurethane to some extent, and the presence of TDI not only prolongs the length of the branch and increases the entanglement degree between the branches and the molecules but also makes the branches contain a strong polar electron-withdrawing isocyanate group and a urethane group, impacting the branch and the main chain with strong hydrogen bonding effect. Herein, the influencing factors of polyurethane on damping property are explored separately from the perspective of hydrogen bonding and microphase separation. By means of Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), atomic force microscopy (AFM), and broadband dielectric relaxation spectroscopy, the results show that E'30 °C/E'70 °C is able to reach 268.28 with the increased proportion of branches, indicating the dropped degree of microphase separation of polyurethanes. Furthermore, the hydrogen bonding effect is enhanced by characterization with FTIR. The two aforementioned effects make the damping properties of polyurethanes more excellent; the effective damping (tan δ ≥ 0.3) can even exceed 150 °C (?50?100 °C). Simultaneously, the polyurethane has a certain self-healing property after the introduction of branches, which is of great significance to extend the service life of polyurethanes
Abstract: An airship is a kind of light-than-air vehicle, which is composed of a gas-filled cyst body and a propulsion system. The airship mainly flies in near-space, and because of the exposure to the lower temperature, solar radiation and long-term operation, it is difficult to avoid failure. Therefore, how to solve the failures of the airship and increase its safety has been a significant topic. The recent research on a fault-tolerant control system can be divided into two parts, active and passive fault-tolerant control. The active fault-tolerant control system requires a fault detection module to obtain the fault information, and then the reconfiguration control law will be reconstructed by the fault-tolerant control module. In this way, the design of the controller is very complicated and the parameters are more difficult to adjust. The passive fault-tolerant control develops a control system based on robust theory without changing the controller and system structure, which doesn’t need the fault information. In this paper, an adaptive sliding mode controller (ASMFTC) was developed for multi-propeller airship with the faults of actuators, where the external wind disturbances and control input saturation were also considered. A four-DOF dynamic model of the airship was established, and the novel fault model of the vectored propellers was designed. The fault system model of the multi-propeller airship was then built. Based on the sliding mode control theory, an integral sliding surface was presented with the residue between the trajectory and states of the airship, in order to deal with the problems of the offset faults and external disturbances, the adaptive law was designed. Thus, an adaptive sliding mode fault-tolerant control controller was proposed. The global asymptotic stability of the system is guaranteed by Lyapunov theory. The effectiveness and robustness of the controller are demonstrated by simulation results of a multi-propeller airship designed by Shanghai Jiao Tong University.
Abstract: Moving target recognition in a complex environment is recently an important research direction in the field of image recognition. The current research focus is how to track moving objects online in complex scenes to meet the real-time and reliability requirements of image tracking and subsequent processing. With the in-depth application of unmanned factory, intelligent safety supervision and other technologies in the field of manufacturing industry, dynamic recognition technology in the complex environment represented by a visual recognition warning system has become an important research in the field of intelligent industry, and the detection requirements of high reliability and real-time for mobile target detection have been identified. In the industrial level vision recognition warning system described in this paper, the hair area of operators was difficult to be segmented in real time because of its irregular movement. To solve this problem, a space-time predictive moving target tracking algorithm was proposed based on the SiamMask model. This algorithm combined the SiamMask single target tracking algorithm based on the PyTorch deep learning framework with ROI detection and STC spatiotemporal context prediction algorithm. According to the online learning of the spatiotemporal relationship of the target, it predicted the new target location and corrected the algorithm of the SiamMask model to realize the fast recognition of the target in the video sequence. The experimental results show that the proposed algorithm can overcome the influence of environmental interference and target occlusion on the tracking effect, reducing the target tracking error recognition rate to 0.156%. The computational time cost is 30 frames per second, which is 3.2 frames per second greater than the frame rate of the improved SiamMask model and 11.94% greater efficiency than that of the original SiamMask model. The algorithm meets the requirements of accuracy and real-time performance of the visual recognition and early warning system, and has reference significance for the application of the moving target recognition algorithm model in a complex environment.
Abstract: Ground-penetrating radar (GPR) has been used in a wide range of shallow detection applications, such as underground geological mapping, highway detection, and hydrogeology survey. In recent years, GPR has been most widely utilized in tunnel geological prediction because it has the advantages of high resolution, intuitionistic results, and fast scanning. In addition, GPR signal is a typical nonstationary and time-varying signal, with its electromagnetic wave exhibiting strong absorption attenuation and dispersion as it propagated in complex surrounding rock. At the same time, the GPR response is often characterized by a weak signal and a strong interference because of numerous system interferences in the tunnel detection environment, which lead to difficulties in data processing and interpretation. Therefore, interference elimination is always a difficult problem when GPR is applied to tunnel geological prediction. In this study, through the introduction of shearlet transform (ST) to GPR signal processing, an adaptive thresholding method is proposed to eliminate random interference on the basis of the energy difference between effective and interference signals in the shearlet domain at different scales and directions. The advantages of this method in random interference removal are verified by forward simulation data. On this basis, the interference signal, as well as its energy proximity and frequency anomaly, common in advanced tunnel geological prediction is taken as an example to illustrate the effect of wavelet transform (WT) on its removal. In this manner, WT and ST are combined to suppress interference. First, WT is used to separate abnormal frequency interference. Then, ST based on the adaptive thresholding method is used to suppress random interference. The results of practical engineering cases of karst cave detection in the field show that the method proposed in this study can remove the interference signal, retain the effective signal, and highlight the abnormal geological area on the basis of the processed waveform stacking diagram to improve the interpretation accuracy of GPR data.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
