Surface Elements Research Articles

Energy gain kernel for climate feedbacks. Part II: Spatial pattern of surface amplification factor and its dependency on climate mean state

Abstract In this study, we examine the spatial pattern of the surface amplification factor (SAF). SAF corresponds to the surface element of the energy gain kernel derived in Part I of this three-part series papers, representing the amplification rate of input energy perturbations at the surface. At a given location, SAF amplifies surface energy perturbations at an equal rate regardless of their origins. Therefore, the spatial variation of SAF can provide insight into the spatial variability of climate sensitivity. The global mean of SAF is about 2.6, and its spatial pattern closely resembles the climate mean cloud field. SAF values range from 4 over the western equatorial Pacific, 2.8-3.2 over mid-latitude storm track regions, and 2.0-2.8 over the Arctic, to 1.4-1.7 over the Antarctic. The more longwave (LW) absorbers in the atmosphere, the greater SAF is. Therefore, SAF is greater in regions where atmospheric water vapor is abundant such as the tropics, and where clouds are prevalent such as mid-latitude storm tracks and the Arctic, but have smaller values close to unity in cold, high-elevation regions. Moreover, SAF tends to negatively correlate with surface temperature when LW absorbers are abundant and positively when they are scarce. With limited LW absorbers, SAF exhibits a negative (positive) correlation in cold (warm) conditions. While the spatial pattern of surface temperature plays a secondary role in shaping SAF, it may help explain why the climate sensitivity in models can either increase or decrease with surface temperature depending on the LW absorbers in the atmosphere.

Evaluation of cross-linkers in the design of immobilized multi isomerase cascade for the preparation of rare sugars.

The cascade of sugar isomerases is one of the most practical methods for producing rare sugars, and enzyme immobilization endows it with high economic efficiency, operational convenience and reusability. However, the most employed cross-linker glutaraldehyde (GA) has the disadvantages of enzyme deactivation and limitation of substrate binding. Herein, three compounds, glyoxal, GA, and 2,5-furandicarboxaldehyde (DFF) were evaluated within a previously developed cascade comprising ribose-5-phosphate isomerase and D-tagatose-3-epimerase to prepare D-ribulose form D-xylose. Analyses of surface morphology, element and chemical bond revealed that all compounds effectively cross-linked the isomerases. High concentration of the cross-linkers was generally beneficial for binding protein and preventing enzyme leak during reusing cycles. Glyoxal performed the highest immobilization rate, though it hadn't been employed as a cross-linker for enzyme immobilization. DFF mediated cross-linking revealed the highest activity recovery, substrate conversion and residual activity after reusing cycles, suggesting better biocompatibility than glyoxal and GA. After 8 rounds of recycling, the residual activity of enzyme immobilized by DFF was 61.4 %, ~30 % higher than that of GA. This study proved a potential alternative cross-linker DFF for the immobilization of enzyme cascade with high activity recovery and reusability, which could promote the efficient production of high value-added products from biomass monosaccharides.

A detection method for multi-type earth's surface anomalies based on multi-dimensional feature space

ABSTRACT On-orbit processing is an important research direction in the real-time remote sensing detection of earth's surface anomalies (ESSA). However, existing methods cannot comprehensively utilize multi-dimensional remote sensing characteristics to detect multi-type ESSA simultaneously. Meanwhile, it is difficult to realize the comprehensive utilization of multi-dimensional remote sensing characteristics for the limited storage and computing resources on satellites. Therefore, this study proposed a detection method for multi-type ESSA based on multi-dimensional feature space. The proposed method first selected the remote sensing characteristics reflecting the basic earth's surface elements to construct a multi-dimensional feature space and proposed two comprehensive remote sensing characteristics. Then, these characteristics were used to build a prior knowledge base reflecting the normal earth's surface conditions. Finally, by comparing the real-time acquired data and prior knowledge base, this study completed ESSA detection. The validation results indicated that the proposed method can effectively detect multi-type ESSA with an accuracy of over 85%. Moreover, the proposed method simplifies the large and complex ESSA remote sensing characteristic system, which greatly reduces the complexity of ESSA detection methods and increases the possibility of on-orbit processing.

Study of Interfacial Reaction Mechanism of Silicon Anodes with Different Surfaces by Using the In Situ Spectroscopy Technique.

The interfacial reaction of a silicon anode is very complex, which is closely related with the electrolyte components and surface elements' chemical status of the Si anode. It is crucial to elucidate the formation mechanism of the solid electrolyte interphase (SEI) on the silicon anode, which promotes the development of a stable SEI. However, the interface reaction mechanism on the silicon surface is closely related to the surface components. This work systematically investigates the interfacial reaction mechanism on silicon materials with three representative coatings of graphene, TiO2, and SiO2 by ex situ X-ray photoelectron spectroscopy (XPS) and dynamic analysis in operando attenuated total reflection-Fourier transform infrared (ATR-FTIR), in situ revealing the different ring-opening mechanisms of fluoro-ethylene carbonate (FEC) and ethylene carbonate (EC) on different silicon surfaces with varying electrical conductivities. Due to the different ring-opening mechanisms, the final decomposition product of FEC on the graphene/electrolyte interface is stable LiF, while on the oxide (native SiO2 or emerging TiO2) interface, it forms an unstable solid lithium compound •CH2CHFOCO2Li. This study demonstrates that the formation mechanism of the SEI on silicon-based electrodes is related to the electron conductivity of surface elements, providing a theoretical basis for further optimization of silicon-based composite materials.

The mechanical behavior and deformation mode of multilayer composite structures based on triply periodic minimal surface elements

In this paper, the mechanical behavior and compression deformation mode of three types of composite multilayer structures based on triply periodic minimal surfaces (TPMS) were conducted through experiments and finite element analysis. The results indicate that the load-displacement curves under varying stain rates manifest a double-platform characteristic for all three structure types. The P-G four-layer structure and P-G six-layer structure have no discernible extrusion of the structural layers during compression, and the entirety of the structure displays an almost regular cubic configuration after compression. Nevertheless, local separation was observed in the extruded portion of the P-H six-layer structure after the structural deformation at higher strain rates. For the other conditions, the structure exhibited a bulge but did not display any local detachment or separation phenomena. During the deformation of the P-H six-layer structure, a dome-shaped region emerges in the first and fifth layers. The “crown” layer displays an inverted bell-shaped failure mode for the first layer structure, exhibiting downward extrusion. In contrast, the fifth layer structure displays an upward extrusion and exhibits a bell-shaped failure mode. The P-H 6-layer structure has the best energy absorption performance under quasistatic compression conditions for the P-G 4-layer, P-G 6-layer and P-H 6-layer structure. However, the energy absorption performance of the identical structure remains largely consistent across varying strain rate conditions.

The Lambert diffuse reflection model revisited.

The Lambert diffuse reflection model is used widely in computerized prediction of sound in rooms as well as for outdoor scenarios. One seemingly surprising consequence of the model was pointed out by Borish [J. Audio Eng. Soc. 34, 539-545 (1986)]: A diffusely reflecting, non-absorbing wall seems to give a 3 dB stronger reflection than a specularly reflecting wall for a source and receiver along the same plane normal. Similar observations have been made by others, and it is usually commented that the two reflection types distribute the reflected energy in different directions. The aspect of energy conservation does not seem to have been sorted out entirely. It is shown here that the difference between an omnidirectional receiver, like a microphone, and a surface element receiver, which can give the total reflected power, explains the claim. Analytic solutions and numerical evaluations of the well-known integrals for a single infinite wall confirm that energy conservation is indeed maintained and also lead to a spatial distribution of the Lambert reflection strength, which differs substantially from the previously published values. The special case can serve as a useful benchmark test of implementations of diffuse reflections, which follow Lambert's law.

Studying the Feasibility of Creating Anisotropic Highly Hydrophobic Polymer Surfaces by Ion-Track Technology

In the last two decades, the creation and research of superhydrophobic nanomaterials based on the “lotus effect” have attracted great interest. The effect is caused by the heterogeneous wetting of rough surfaces, when the grooves of a rough surface are filled with air (vapour) and water only contacts the tops of the protrusions. The drop forms a sphere on the surface and, if slightly inclined, rolls down and picks up the dirt particles. A wide variety of methods have been developed to produce such materials, among which potential of the ion track technology (ITT) is being explored. The aim of this research was to investigate the wettability of surface microrelief using two materials with different initial hydrophobicity degrees. By modifying the surface of polycarbonate and polypropylene films using the ITT, the samples with water contact angles of 140 ± 5° and 151 ± 5° at maximum, respectively, were obtained. It is shown that such angles are characteristic of microrelief, where the fraction f of the surface that is in contact with the droplet is decreased to the range 0 f 0.3. In order to increase the probability of droplets rolling down the material surface in a certain direction, the materials with inclined microrelief were obtained. In this case, the wettability becomes anisotropic. The droplet loses its spherical shape, deforming in the direction of inclination of needle-like surface elements. It was found that the anisotropy of wettability is higher at an inclination angle of the relief elements of 45° than that at 30° (relative to the flat surface).

Investigation of the effect of dead volume on the shape of breakthrough curve – New method designed to correct this effect

At laboratory scale, the reactor volume may be the same order of magnitude as the dead volume of the experimental set-up. The purpose of this study is to provide a new simple method to obtain a breakthrough curve on an inert porous media (without adsorption), corrected from the influence of the dead volume, to study only the effect of the axial dispersion. Indeed, our study parameters (pressure, low flow rate, fixed bed column filled with an inert porous media) did not allow us to use the classical and simple method, known as Point by Point (PBP). This new method (Elementary Surface Area ESA) is based on the substraction of elementary surfaces of dead volume and raw breakthrough curves, whereas the PBP method is built on a point by point substraction. Therefore, each elementary surface, defined by two points of the breakthrough curve, induces a smoothing of the fluctuations observed by the PBP method. So the ESA method could be considered as an inprovment of PBP one. Analysis of breakthrough curve requires calibration of the measurement devices for both flow rate and gas stream composition. Some calibration results are also presented in this paper.

Physically-based digital geomorphological mapping: Case study of glacial and karst topography

Digital geomorphological mapping is considered here as a semi-automated procedure of division the land surface into genetically meaningful objects. The basis is automatic segmentation into elementary forms, the smallest and indivisible elements of the land surface, should be geometrically clearly identifiable, with maximal internal homogeneity and clear discontinuities at their boundaries. These elements can then be combined into more complex genetically homogeneous composite forms. Given the crucial role of gravitational energy in landform formation, it should also be considered in elementary land surface segmentation . This research builds on the theoretical foundation of physical geomorphometry, which explores the relationship between gravitational energy and geomorphometric variables. Specifically, we apply the recently published algorithm for physically-based elementary land surface segmentation by Minár et al. (2024), which utilizes dynamic least squares (DLS) generalization within a GEOBIA framework. The algorithm was initially tested in structurally fluvial hilly terrain using nine physically interpretable gravity-specific point-based variables (elevation, slope aspect and gradient, three basic curvatures, and three changes in curvature). In this study, we extend the application of this algorithm to two different areas of the Western Carpathians: the glacial topography of its highest part and a karst plateau. By using a slightly simplified and specifically modified version of the physically-based algorithm, we achieved plausible and genetically interpretable results in both case studies, which confirms the value of physical geomorphometry in geomorphological mapping. Additionally, a novel concept of physical-geomorphometric signature was applied in both case studies as a support for the physical-geomorphometric analysis. The physical-geomorphometric signature is very helpful in the quantitative comparison between various genetic groups of landforms.

A simple model for faceted topographies at normal faults based on an extended stream-power law

Abstract. Mountain fronts at normal faults are often faceted in the sense that they contain strikingly planar surface elements that follow the surface trace of the fault. Since the dip angle of the facets is typically much lower than the dip angle of the fault, it is clear that the facets are not just the exhumed footwall but have been eroded considerably. It has also been shown that a constant erosion rate in combination with a constant rate of displacement can explain the occurrence of planar facets. Quantitatively, however, the formation of faceted topographies is still not fully understood. In this study, the shared stream-power model for fluvial erosion and sediment transport is used in combination with a recently published extension for hillslopes. As a major theoretical result, it is found that the ratio of the tangents of the facet angle and the dip angle of the fault as well as the ratio of the baseline length and horizontal width of perfect triangular facets mainly depend on the ratio of the horizontal rate of displacement and the hillslope erodibility. Numerical simulations reveal that horizontal displacement is crucial for the formation of triangular facets. For vertical faults, facets are rather multiangular and much longer than wide. While the sizes of individual facets vary strongly, the average size is controlled by the ratio of hillslope erodibility and fluvial erodibility.

Identification of priority factors for risk control of trace toxic elements in surface resuspended dust of university campuses

The surface resuspended dust (SRD) that accumulates trace toxic elements (TTEs) can be suspended in the atmosphere and can be transported to other areas, such as campuses, through airflow. The risks and sources of TTEs in university campus SRD have not been thoroughly explored, especially the priority factors for TTEs pollution and risk control in the SRD. Taking Xi’an as a case, this study quantitatively apportioned the sources of TTEs in the SRD of university campuses using positive matrix factorization method, evaluated the ecological and health risks of the specific-source TTEs in the SRD using Monte Carlo simulation method, and determined the priority factors for risk control of TTEs in the SRD. We found that the pollution of Zn, Pb, and Cu in the SRD was severe, with significantly high to very high enrichment levels. The comprehensive pollution of TTEs in the SRD was high to extremely high levels, with Pb and Zn as the main contributors. The four sources of TTEs identified in the SRD were traffic exhaust, traffic non-exhaust, mixed, and natural sources, accounting for 19.1%, 43.3%, 11.2%, and 26.3% of the total TTE concentrations, respectively. The ecological risk of TTEs was quite serious, mainly caused by traffic exhaust Pb. TTEs in the SRD had a certain cancer risk to college students, mainly contributed by traffic exhaust. Traffic exhaust source is the main factor that needs to be controlled.

Enhancing wear resistance and biocompatibility of medical ZrNb alloy used for artificial joint via femtosecond laser surface processing combined with thermal oxidation

Zr-2.5Nb alloy is widely used as an implant material in the biomedical field. Zr-2.5Nb alloy was subjected to laser processing and laser processing combined with thermal oxidization composite treatment to investigate the effects of different structures and surface treatments on its morphology and surface element distribution, corrosion, friction properties and biocompatibility. The results show that after laser processing alone, ZrO2 and Nb2O5 appear on the surface, but the oxide film is thin, and after composite treatment, t-ZrO2 appears on the surface of the Bulge structure. Meanwhile, the corrosion resistance of the alloy in simulated body fluids is significantly improved after composite treatment, among which the LIPSS structure has the strongest corrosion resistance, and the corrosion current density is improved by two orders of magnitude in comparison with that of the substrate. The results of the wear volume experiments show that the wear resistance of both the laser treatment and its composite treatment is improved, with the LIPSS structure having the best performance. In addition, the composite treatment was shown to be biocompatible and suitable for use as an implant material.

Carboxylic acid-based fuel mediated sustainable one-pot fabrication of CaFe2O4 with enhanced adsorptive elimination of hazardous dye

The present work successfully demonstrated the morphological variation of CaFe2O4 (CFO) concerning various fuels (carboxylic acid groups contain compounds) using a one-step combustion technique. The SEM analysis of the CFO suggests the formation of sharp-edge rocky crystals to highly agglomerated porous clumps concerning the role of fuel. The x-ray diffraction analysis suggests that all samples of CFO are nanocrystalline orthorhombic structure constituted <50 nm. The BET and EDX analysis discloses that CFO s surface area and element composition is highly depend on the fuel molecule (reducer). The CFO performs efficacious in the adsorptive removal of hazardous dye Acid Fuchsin (AF) from an aqueous medium in a slightly acidic environment (pH 6). The AF removal was engaged with the batch adsorption method and optimized the process’s essential parameters (amount of adsorbent, initial AF concentration, and time) were optimized to achieve the utmost efficiency. The AF adsorption was well described by the Langmuir isotherm with outstanding adsorption capacity in the order of CFO-OA (Oxalic acid) (866) < CFO-TA (Tartaric acid) (1063) < CFO-CA (Citric acid) (1504) < CFO-MA (Malonic acid) (1656 mg/g). The adsorption energies were estimated from the Dubinin-Radushkevich model, indicating that adsorption occurs via the chemical process. The pseudo-second-order (PSO) kinetic model was better at explaining the uptake of AF, and the Intraparticle diffusion model indicated that pore diffusion was the rate-controlling step. The reusability test shows that the CFO has high efficiency up to five regeneration cycles. Thus, the work suggests that CFO could be an eco-friendly, cost-effective alternative adsorbent for wastewater treatment.

Enhancing coloration performance and colour fastness of nano‐pigment ink‐jet‐printed blended fabrics through cationic and water‐repellent surface modification

AbstractThe coloration performance and colour fastness properties, crucial for industrial textile printing, depend on the spreading and fixation behaviour of ink‐jet droplets on porous fabrics. Current nano‐pigment‐based ink‐jet applications provide unstable results for these properties, especially for synthetic and blended fabrics. This study focuses on cellulose‐based blended fabrics as substrates to modify the wetting properties of fabrics through cationic and water‐repellent treatments, to improve the coloration performance and colour fastness systematically. The study conducted analytical experiments to analyse the surface element composition, ion potential and surface morphology of the fabrics. Differences in printing colour and pattern performance were attributed to the behaviour of ink droplet spreading on the fabric surface and inside the fabric, including wetting time, colourant distribution, and ring shape. The results indicate that ink droplet spreading on fabrics significantly influences printing pattern sharpness, including edge clarity and colour intensity, which can be improved through surface modification, including cationic and water repellent treatment. The use of blended fabrics treated with 1% cationic modifier and 0.05% fluorine‐containing water repellent resulted in effective suppression of droplet formation and significant enhancement of colour performance and fastness. Furthermore, as the ink droplet volume decreased from 5 to 1 μL, the coffee ring effect on the fabric treated with the water repellent agent gradually diminished, leading to improved printing sharpness during the printing process.

High‐Entropy Phosphide Catalyst‐Based Hybrid Electrolyzer: A Cost‐Effective and Mild‐Condition Approach for H2 Liberation from Methanol

AbstractMethanol as a hydrogen carrier provides a practical solution for H2 storage and transport, but traditional reforming faces challenges with low efficiency, CO2 emissions, and the need for specialized infrastructure. In this study, a reliable approach for fabricating low‐cost electrodes is presented by in situ growing high‐entropy phosphide nanoparticles on nickel foam (FeCoNiCuMnP/NF). This cost‐effective design is specifically engineered for alkaline methanol oxidation reactions (MOR), achieving a current density of 10 mA cm−2 at an applied voltage of only 1.32 V, while also demonstrating exceptional selectivity for formate products. Advanced Monte Carlo (ML‐MC) simulations identify copper as the predominant surface element and highlight phosphorus coordination as a key factor in enhancing catalytic activity. The field is advanced with a pioneering hybrid acid/alkali flow electrolyzer system, integrating FeCoNiCuMnP/NF anode and commercial RuIr/Ti cathode to enable indirect hydrogen liberation from methanol. This system requires an electrolytic voltage as low as 0.58 V to achieve a current density of 10 mA cm−2 and remains stable for hydrogen liberation over 300 h of operation. This achievement not only offers a highly efficient alternative to indirectly liberate H2 stored in methanol but also establishes a new benchmark for sustainable and economically viable H2 production.

Pollen morphology of Eremogone (Caryophyllaceae) in Türkiye

The palynological characters of 17 taxa belonging to genus Eremogone Fenzl (Caryophyllaceae) from Türkiye were examined using light microscopy and scanning electron microscopy. Eremogone pollen in Türkiye is found to have an average size of 31.31 μm (26.62‒36.65 μm), pore sizes ranging from 6.52 to 9.24 μm, inter-pore distances ranging from 9.07 to 12.57 μm, pore numbers varying from 5 to 14 and 5‒30 nanoechini distributed in an area of 10 × 10 µm. The ornamentation was identified as nanoperforate, nanoechinate, or nanofaveolate surface elements in various combinations. Clustering analysis and Principal Component Analyses do not show clear groups, although more similar taxa were brought together through the analysis of pollen micromorphological data rather, the nanoechinate base width, nanoechinate length, and pore diameter length are the most valuable variables for separating the examined taxa.

The Spatiotemporal Evolution of the Mudflat Wetland in the Yellow Sea Using Landsat Time Series

Mudflat wetland, one of the 27 surface elements identified by the International Geographic Data Committee, has undergone substantial transformations with the rapid growth of the social economy and marine hazards, resulting in significant changes in its area and distribution. Quick identification of mudflat wetland evolution is vital to improve the mudflat ecological service value. We employed object-oriented and decision tree classification methods to map the mudflat wetland in the Yellow Sea using the Landsat time series from 1983 to 2020. The Improved Spectral Water Index (IWI) was established by combining the characteristics of many ratio indices and using ratio operation and quadratic power operation. The coefficient of variation (CV) of the IWI was calculated, and the range of the intertidal zone in 1983, 1990, 2000, 2010, and 2020 was obtained by using a threshold method. The results indicate that the mudflat wetland area decreased continuously from 1983 to 2020, with a reduction of 337.38 km2/10a. Among the total area, the natural wetland experienced a decline of 446.9 km2/10a, with the most drastic changes occurring between 2000 and 2010. In contrast, the area of the human-made wetland increased by 109.56 km2/10a. Over the 38 years, the tidal flat has undergone the most drastic reduction, with an average of 157.45 km2/10a. From 1983 to 2020, the intertidal zone area decreased, with a reduction of 429.02 km2/10a. Human activities were the key factors causing mudflat wetland loss. Based on these findings, we propose several policy suggestions. This study provides a scientific basis for understanding the synergetic evolution mechanism of coastal resources utilization and mudflat wetland protection under global change.

Wear properties of Al6061/SiC + B4C + TiC hybrid composites produced by vacuum infiltration method

Abstract In the study, hybrid metal matrix composite (HMMC) structures were produced by vacuum infiltration method (VIM) using Al6061 alloy and varying amounts of SiC, B4C, and TiC ceramic powder pairs. Age-hardening processes were applied to these HMMCs. After heat treatment, wear behavior was examined under different loads using the pin-on-disc test method. All Al6061 hybrid composites exhibited better wear performance than unreinforced Al6061. In the wear tests of composite samples, the lowest volume loss and therefore the highest wear resistance were obtained in Al6061 3 wt.% B4C + SiC composites under 5 N force. The lowest wear resistance due to the highest volume loss was determined in Al6061/1 wt.% TiC + B4C composites under 15 N force. Abrasive and adhesive wear characteristics were observed in field emission scanning electron microscopy(FESEM) images of worn surfaces. Additionally, wear debris, smearing, and deep grove formations were determined on the surface. In the EDS analysis performed on the worn surface, O and Fe elements were found in addition to the elements that are likely to be in the structure (such as Al, B, C, Ti, Si, and Mg). The wear tests caused the formation of oxide layers on the sample surfaces.

Research on adhesion properties of tidal flat soil on metal surface and discrete element simulation

The adhesion property of soil on the metal surface was tested by the orthogonal experiment with 4 factors and 3 levels based on piston pull out method. A regression model of adhesion stress and the factors including moisture content(X1), pressing time(X2), settling time(X3) and separation velocity (X4) was established. The experiment results show that the influence of each factor on adhesion stress is ranked as X1≈X2≈X3>X4>X3X4, and the adhesion stress shows an ‘S’ curve with the increase of separation velocity. The DEM parameters of the soil were calibrated based on the test results, and the contact and disturbance state of soil particles during the test were studied by discrete element method (DEM) using JKR model. The simulation tests show that the maximum adhesion stress occurs when the particles are about to separate from the probe surface, and the soil disturbance state is hierarchical.

Synergistic degradation of refractory organic pollutant by underwater bubbling plasma combined with heterogeneous Fenton process

Excessive discharge of the refractory organic pollutants endangers the development of the society and economy, thus seeking an efficient wastewater abatement method is an urgent need. Herein, Iron (Ⅱ) sulfide (FeS) was employed as the heterogeneous catalyst and coupled with underwater bubbling plasma (UBP) for the elimination of the refractory organic pollutant, malachite green (MG). FeS catalyst was synthesized using the solvothermal method and subsequently characterized comprehensively, focusing on its microstructure, specific surface area, chemical bonds and elements valence states. The UBP system combined with FeS (UBP/FeS) exhibited the robust synergism with a maximum synergistic factor of 1.89. The MG degradation percentage and rate constant were up to 94.7% and 0.237 min−1 within 12 min. The parameter experiments revealed that FeS dosage, pulse frequency, initial MG concentration and solution conductivity of 150 mg/L, 56 Hz, 5 mg/L and 21.8 μS/cm, respective, were more conducive for MG elimination. The MG removal efficiency reached 86.2% after five consecutive applications of FeS. Reactive substances including ·OH, ·O2−, eaq, O3 and H2O2 were confirmed to contribute to MG elimination. Additionally, the conversion circle between ≡ Fe(Ⅱ) and ≡ Fe(Ⅲ) promoted the catalytic conversion of H2O2 and O3 into ∙OH. The comparison of UV–vis spectra and total organic carbon of MG solution before and after reaction revealed the superior degradation of MG in the UBP/FeS system. Hypotheses regarding to the decomposition pathways of MG were formulated based on the identified intermediates. The toxicity level of MG solution was lightened after reaction. The above results indicate that UBP/FeS has the advantages of quick degradation and high efficiency, representing a promising approach for refractory pollutants treatment.