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To control the diffusion of high concentrations of coal dust during tunnel boring and minimize the threat to the life and health of coal miners, theoretical analysis, numerical simulations, and field measurements were combined in this study. First, computational fluid dynamic simulation software was used to simulate the generation of dust particles and their transport pattern in the tunnel. Subsequently, an innovative orthogonal test was performed to study the effect of four ventilation parameters [the pressure airflow rate (Q), distance between the air duct center and heading face (L A ), distance between the air duct center and tunnel floor (L B ), and distance between the air duct center and nearest coal wall (L C )] on dust diffusion. According to the orthogonal test results, the optimal ventilation parameters for effective dust control are as follows: Q = 1400 m 3 /min, L A  = 7 m, L B  = 2.8 m, and L C  = 1 m. The optimized set of ventilation parameters was applied to the Wangpo 3206 working face. The results show that dust diffusion in the tunnel was effectively controlled and that the air quality was sufficiently improved., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Achieving efficient and stable photocatalytic degradation of xylene hinges on the advancement of photocatalytic materials with outstanding visible light activity. This low-carbon strategy serves as a promising solution to combat air pollution effectively. In this study, we synthesized a Z-scheme heterojunction Ag@CuO/UiO-66-NH 2 nanocomposite by hydrothermal method to investigate its photodegradation properties for xylene gas under visible light conditions. XRD, XPS, SEM, FTIR, and UV-vis analyses were employed to confirm the presence of the Z-scheme heterojunction. The CuO/UiO-66-NH 2 (CuU-2) composite has high photocatalytic activity, which is 2.37 times that of the original UiO-66-NH 2 . The incorporation of Z-scheme heterojunction facilitates efficient charge transfer and separation, leading to a substantial enhancement in photocatalytic activity. The Ag@CuO/UiO-66-NH 2 (Ag-1@CuU) composite has the highest photocatalytic activity with a degradation efficiency of 84.12%, which is 3.36 times and 1.41 times that of UiO-66-NH 2 and CuO/UiO-66-NH 2 , respectively. The silver cocatalyst improves the absorption capacity of the composite material to visible light, makes the ultraviolet visible absorption edge redshift, and significantly improves the photocatalytic performance. This study introduces a novel approach for xylene gas degradation and offers a versatile strategy for designing and synthesizing metal-organic framework (MOF)-based photocatalysts with exceptional performance., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To solve the problem of high-concentration dust pollution in a bored tunnel, we conducted a simulation study on the dust transport law and air age of the wind flow in a bored tunnel under different ventilation methods. Air age was innovatively introduced as an index for evaluating tunnel air quality. The results show that dust pollution is serious under conditions of press-in ventilation, which is unfavorable to personnel operations. Following the installation of an on-board dust-removal fan, an effective dust-control air curtain forms in the tunnel, and the high-concentration dust is essentially controlled within the range of Z = 13 m from the working face. The dust concentration in the working area on the left side of the tunnel is C D  < 200 mg/m 3 , and the dust-control effect is obvious. At the same time, the air age on both sides of the tunnel is reduced by 35.5% following the use of the on-board dust-removal fan. Taking into account dust control by ventilation and dust removal by fan, spraying dust reduction measures are added, and we developed automated wind-mist synergistic wet high-frequency oscillation dust-capturing technology for tunnel boring. This could effectively improve the problem of high levels of coal dust pollution in tunnels., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Particulate matter (PM) is one of the most harmful exhaust pollutants to human health. In this study, the PM diffusion and distribution emitted by trackless rubber-tyred vehicle under different driving conditions in coal mine were analyzed with numerical simulations and field measurements. The results show that when the vehicle velocity was constant, the PM concentration of the trackless rubber-tyred vehicle decreased with increasing distance from the exhaust pipe orifice. In addition, the proportion of PM with a concentration below 10 mg/m 3 was the highest owing to the influences of diffusion and airflow dilution. However, when the diffusion distance is less than 3 m, the PM concentration far exceeds the occupational exposure limit (10 mg/m 3 ). In this case, underground personnel should stay away from the area near and along the exhaust pipe as far as possible. With increasing vehicle velocity, the PM concentration gradient at a diffusion distance of 0-6 m showed the most significant slope. Besides, the concentration fluctuation of PM was the largest and relatively high when the diffusion distance was 5-15 m. Therefore, the area 15 m from the exhaust gas pipe opening of the trackless rubber-tyred vehicle should be controlled. In addition, the relative errors between the measured and numerical simulation results were mostly less than 10%, which proved that the numerical simulation results were reliable., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A convection-type air curtain dust control system and method were proposed to effectively control the high dust concentrations generated during the operation of coal miners and hydraulic supports and to reduce the dust concentration in the entire working space of longwall work surfaces, and the effectiveness of air curtain dust control during single process operation was investigated through numerical simulation. The results showed that when the miner was working alone, there was a significant difference in the concentration distribution inside and outside the dust-proof air curtain, with significantly lower dust concentrations in the area where the miner drivers were operating compared to both sides, with an average dust mass concentration of around 420 mg/m 3 . Dust concentrations increased to about 700 mg/m 3 , but large amounts of dust were prevented from diffusing downwind. This indicates that the dust reduction effect is more pronounced after the equipment is opened, which can improve the working environment and reduce the probability of dust combustion and explosion accidents., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In recent years, . the rapid development of the Yangtze River Delta in China has led to increasingly serious regional eco-environmental problems. Therefore, it is of great significance for the construction of ecological civilization to study the ecosystem health in the Yangtze River Delta. In this paper, the assessment framework of "Vigor-Organization-Resilience" was used to assess the ecosystem health index (EHI) of the Yangtze River Delta from 2000 to 2020, and then the spatial autocorrelation method was used to analyze the agglomeration of EHI in 314 counties in this region. Finally, the eXtreme Gradient Boosting (XGBoost) model and the SHapley Additive exPlanation (SHAP) model were combined to explore the synergistic impact of EHI driving factors. The results show that (1) from 2000 to 2020, the EHI in the Yangtze River Delta is at the level of ordinary health, and gradually decreased; (2) the EHI has significant spatial positive correlation and aggregation; (3) the driving factors in descending order of importance are urbanization level (UL), precipitation (PRE), PM2.5 (PM), normalized difference vegetation index (NDVI), and temperature (TEMP); and (4) the relationship between UL and EHI is logarithmic; PRE and EHI are quartic polynomial; PM, NDVI, TEMP, and EHI are quadratic polynomial. The results of this paper are of great significance to the management and restoration of the ecosystem in this region., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Bolter miners are being increasingly used. Unfortunately, this mining technology causes a considerable amount of air pollution (especially by methane and dust) during excavation. In this study, the multiphase coupling field of airflow-dust-methane for different distances between the pressure air outlet and the working face (L p ) was simulated by using the FLUENT software. The migration law of pollutants in the multiphase coupling field was analyzed, and the distance parameters between the pressure air outlet and the working face were optimized. Finally, the simulation results were verified based on the field measurement results. We found that the blowdown effect was more obvious when 14 m ≤ L p  < 16 m compared with other conditions. The peak value of dust concentration within this distance range was the smallest (44.4% lower than the highest peak value, which was verified when L p  = 18 m), while the methane concentration was < 0.6%. A high-concentration area (where methane concentration > 0.75%), identified near the walking part of the bolter miner, was 13 m shorter than the largest (when L p  = 18 m). Therefore, we determined that the optimal blowdown distance would be 14 m ≤ L p  < 16 m. Within this range, the dust removal and methane dilution effects are optimal, effectively improving the tunnel air quality and providing a safe and clean environment for mine workers., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The rapid urban renewal progress has generated a large amount of construction and demolition (C&D) waste in China. According to the concept of circular economy (CE), producing products with recycled content (PwRC) is an effective solution to achieve sustainable C&D waste management. However, the low market acceptance of PwRC affects stakeholders' purchase intention, which hinders the development of the PwRC industry. In order to clarify the stakeholders' purchase intention and investigate the influencing mechanism of stakeholders' purchase intention, a novel method which combines structural equation modeling (SEM) with a back-propagation neural network (BPNN) is proposed. The method makes full use of the causal analysis ability of SEM and the nonlinear characteristics of BPNN to simulate and to verify the path of product cues, perceived value, and behavioral intention of stakeholders. The results reveal that the brand and materials of PwRC can affect stakeholders' perceived value, and in turn, affect their purchase intention. Focus on the brand and materials of PwRC will help recycled product manufacturers and governments to promote stakeholders' purchase intention and the development of the C&D waste recycled products market., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Spray dust reduction is a common dust control process in coal mines. However, the actual efficiency of spray dust reduction in a coal mine is low due to poor coal wettability. We select four surfactants that can greatly improve the surface activity of a dust suppressant solution. The wettability of the surfactant solution on coal dust is investigated in terms of two aspects: surface tension and contact angle. The effects of the type of surface-active dust suppressant and its concentration in the spray solution on the wetting of the coal dust and curing effects were analyzed. Numerical simulations were used to simulate spray atomization and to deduce how different types and concentrations of dust suppressant solutions affect the spray. The technical approach of the spray dust reduction method was further optimized by comprehensive analysis and numerical simulations, which could provide guidance for the application of spray dust reduction in coal mines., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The objective and accurate prediction of carbon dioxide emissions holds great significance for improving governmental energy policies and plans. Therefore, starting from an evolutionary system of carbon emissions, this paper studies the evolution of the system, establishes a grey model of the system, and expands the modeling structure of this model. The modeling mechanism of the classical feedforward neural network model is organically combined with the function of the external influencing factors of carbon emissions, and the grey model of the carbon emission dynamic system is established with a neural network. Then, the properties of the model are studied, the parameters of the model are optimized, and the modeling steps are obtained. Finally, the validity of the model is analyzed by using the carbon emissions of Beijing from 2009 to 2018. The results of the four cases show that the simulation and prediction errors of the new model are all less than 10%, and case 1 shows the best results of 1.56% and 2.07%, respectively, which are used to predict the carbon dioxide emissions in the next 5 years in Beijing. The prediction results are in accordance with the actual trend, which indicates the effectiveness and feasibility of the model., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

WC55-Y hydraulic support transporters allow an efficient transport of support equipment in fully mechanized mining faces. However, the diesel particulate matter (DPM) emitted by these transporters seriously pollutes the air environment along mine roadways, endangering the health of coal mine workers. In this paper, we simulated the diffusion dispersion of DPM during the functioning of a WC55-Y hydraulic support transporter (emitting high amounts of exhaust pollutants) by computational fluid dynamics, identifying high DPM concentration zones. While the transporter was driven along a coal auxiliary transportation roadway, the diffusion-dispersion characteristics of DPM changed: DPM reached a long horizontal diffusion distance and a high concentration. We found that to avoid the inhalation of DPM and reduce its potential harm, coal mine workers should keep a distance of at least 21.27 m from the hydraulic support transporter while the vehicle runs along the roadway. Moreover, according to our simulation, the operators responsible for disassembling the hydraulic support transporter should wear protective equipment with good filterability while unloading it. Overall, the findings of this study can be applied to outline new work practice guidelines and design new optimum auxiliary ventilation for reducing underground miner exposure to DPM., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cost-effective new environmental catalysts play a crucial role in purifying NO x from exhaust gas of coal mine diesel vehicle. A new, environmentally friendly catalyst with high catalytic activity and good redox properties was prepared by a microwave-assisted sol-gel method using TiO 2 nanoparticles as a catalyst, which were doped with La and Cr, and adding the surfactant dimethyldiallylammonium chloride (DMDAAC) as an organic modifier. The morphological characteristics, crystalline structure, functional groups, and elemental types of the catalyst were characterized, and the properties of the catalyst, such as redox ability and catalytic activity, were examined with H 2 -temperature-programmed reduction experiments and activity tests. The results showed that the addition of surfactant suppressed the growth of particle size, increased the specific surface area, and improved the redox ability and catalytic activity of the catalyst. I hope to reduce the pollution of NO x to environment and achieve efficient cleaner production., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

During the excavation of high gas mine, gas and dust often exist at the same time. In order to ensure that the gas concentration remains within a safe range and minimize the risk of workers' pneumoconiosis, we simulated the interaction mechanism of airflow, gas, and dust, explored the pollution law of gas and dust, and obtained the optimal purification distance (L p ) by the CFD method. The reliability of the numerical simulation was verified by field measurements. Firstly, the properties of the gas and dust affected the structure of the airflow field. At the same time, the change in the airflow field affected the concentration distributions of the gas and dust. During the diffusion process, some high-risk regions in which the gas or dust concentrations exceeded 0.80% or 200 mg/m 3 , respectively, were discovered. Moreover, we have found that the airflow velocity in the top region of the tunnel and at the intersection corner between the cutting face and tunnel wall was the main factor affecting the purification effects. When L p = 5-8 m, the gas concentration remained below 0.50%. When L p = 6 m, the dust concentration reached a minimum of 287.5 mg/m 3 . Therefore, the optimal purification distance was determined to be 6 m; in which case, the gas and dust concentrations decreased by 32.84% and 47.02%, respectively., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Green technology innovation is the basic driving force of green economic development. The compatibility of the composite system composed of green technology innovation, green finance, and environmental regulation is the decisive factor of whether regional economy can achieve sustainable development. Based on the data of regional green technology innovation in China from 2012 to 2020, this paper discusses the coupling coordination mechanism and coupling coordination level among green technology innovation, green finance, and environmental regulation based on entropy method. It is found that the coupling and coordinated development of regional green technology innovation-green finance-environmental regulation system in China is above medium level. However, there is a big gap in the coupling coordination level among different regions. The coupling coordination level in eastern China is relatively high, and the coupling coordination level in other regions is deviated. Most regions of China have a great potential for improvement. On this basis, this paper puts forward policy suggestions for improving the overall coupling and coordination level of the system to promote national green development., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The development of coal industry is restricted by dust pollution. Air curtain dust control technology was proposed as a solution to the serious problem of pollution. A mixture of numerical modeling and field tests has been used to study this technology. Numerical simulation is used to analyze the dust control effect of this technology under different dust generation conditions. Field measurements are used to verify the effectiveness of this technology. The results show that following the application of this technology, the fan-shaped air curtain generated by the fans forms a trapezoidal protective area between the coal cutter and the sidewalk. This protective area prevents dust from entering the coal-cutter driver's workspace. The average dust concentrations where the coal-cutter driver works were 1590 and 466 mg/m 3 , severally, before and after the implementation of this technology. The dust control rate in this space is approximately 70.69%. This research provides useful data for dust control technology in fully mechanized mining faces, and will contribute to the stable development of coal fuel., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

We investigated the impact of exhaust emissions from hydraulic support transporters on the air quality in roadways in mines. The dispersion distribution of diesel exhaust pollutants emitted by hydraulic support transporters was simulated with a dynamic mesh and computational fluid dynamics (CFD) simulations. More specifically, the dispersion and distribution of the main exhaust pollutants CO, HC, and NOx emitted by vehicles under the influence of the roadway wind flow were simulated with CFD simulations; in addition, the dispersion characteristics of exhaust pollutants from hydraulic support transporters during multiple driving phases in an alleyway (from transporting material, being unloaded at idle speed, to driving off without load) were predicted. The simulation results show that exhaust pollutants emitted by moving hydraulic support transporters can pollute the air in roadways and negatively affect the performance of gas monitoring devices in the roadway. Therefore, coal mining companies should optimize the ventilation design scheme to improve the air quality in roadways: they should increase the ventilation volume to dilute the emitted pollutants; in addition, the positions of underground gas monitoring devices should be adjusted to prevent interference from exhaust pollutants emitted by vehicles. This paper provides the theoretical basis and results of a preliminary investigation of the dispersion and transportation characteristics of exhaust pollutants emitted by vehicles in roadways. The results in this paper can serve as guidance for reducing the risk of occupational diseases., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To effectively reduce high dust concentrations and keep clean air in fully mechanized rock tunnelling faces in coal mine, this study carried out a research of dust suppression technology of the forcing air curtain. First, the mechanism of dust diffusion controlled by the forcing air curtain was introduced in this study. Then, numerical simulations of the formation of the forcing air curtain as well as the influence for dust diffusion under the different distance between forcing air duct outlet and heading end were carried out. Moreover, a dust suppression technology of the forcing air curtain was designed and tested in a fully mechanized rock tunnelling face of southern return air tunnel which was located in the Tangkou coal mine of China. It shows that the numerical simulation results were in good agreement with the in situ tests. The average removal rate of total and respirable dust could reach up to 95.1% and 96.1%, respectively, at manned working areas in the tunnel. Research results show that the dust suppression technology of the forcing air curtain is an effective method of dust control in fully mechanized rock tunnelling faces., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To investigate the influence of dust produced by multi-dust sources at a fully mechanized mining face with a large mining height on the safety conditions in a coal mine, the No. 22305 fully mechanized mining face of the Bulianta coal mine was considered as the research object in this study, and the space-time evolution of dust was analyzed with computational fluid dynamics (CFD). The wind flow simulation results show that the distribution law of wind flow is mainly affected by the structure of the roadway, and the speed and direction of the wind flow change greatly while passing by corners and through large-scale equipment. The dust generation and pollution diffusion laws with respect to time and space were investigated based on simulations of dust production due to 5-s, 30-s, and 60-s coal cutting, continuous coal cutting, and hydraulic support shifting. The space-time evolution law under different dust-producing times shows the transportation and diffusion procedure of dust under the wind flow; the dust-generated via coal mining and shifting were superposed on the downwind side and a 36-m-long dust belt was formed, which filled the coal mining space; the dust concentration in the breathing zone 120 m downwind the front drum had a dust concentration higher than 1700 mg/m 3 , this was the crucial dust-proof area, and effective dust reduction methods should be addressed., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The efficiency of mine excavation has been significantly enhanced by continuing improvements in tunneling capabilities; however, this has also resulted in serious environmental pollution and greater safety risks for workers. To ensure safe production, the focus of this study is on the effect of varying the air pressure and the distance between the air pressure cylinder and the side wall settings on dust dispersion behavior and dust control in excavated tunnels. We also investigated temporal-spatial dust diffusion rules in tunnels by combining numerical simulation data with field measurement results. Through further analysis, when the pressure air volume and the exhaust air volume are both equal to 250 m 3 /min, the dust diffusion distance could be fitted as: [Formula: see text]. When the exhaust air volume is equal to 250 m 3 /min, dust control effects were improved as the pressure air volume decreased, becoming optimal when the pressure air volume dropped to 150 m 3 /min. Under these conditions, areas of high dust pollution were contained within 16 m of the cutting face, and the dust diffusion distance satisfied the formula: [Formula: see text]. When the pressure air volume is fixed, the change of the distance between the pressure air cylinder and the side wall has little effect on the dust diffusion. When the distance is 1.5 m, the dust control effect is the best, and the high dust pollution area is controlled within 14 m of the cutting surface. This alleviated dust pollution to a certain degree, thereby enhancing the air quality and ensuring safer production. This study provides a new understanding of the environmentally sustainable development of tunnels and is of great significance for clean production., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The respirable dust pollution produced in the cutting process of tunnelling machine during tunnelling process is a serious threat to the health of workers. The key to solve this problem is to build an effective ventilation system in the tunnel. In this paper, experiments were designed and implemented to obtain the temporal-spatial evolution of respirable dust pollution before and after the 3D spiral wind-curtain generator was used for tunnel auxiliary ventilation, and the CFD method was used to supplement and visualize the experimental results. Before the 3D spiral wind-curtain generator was used, the respirable dust gradually diffused from the cutting face to other spaces of the tunnel, and finally presented a stable state with time. After using the 3D spiral wind-curtain generator for auxiliary ventilation, the dust diffusion speed in the tunnel was slower than before, and the dust concentration was lower than before. When adjusting the position of the generator and installing it 20m away from the cutting face, an effective dust control wind-curtain formed within the range of 3.5 ~ 6.5m away from the cutting face. With the increase of time, the dust is stably controlled within the space of 4.5m away from the cutting face, and then pumped away by the exhaust fan, so as to purify the tunnel environment and ensure the tunnel's cleanliness and safety and efficient excavation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aiming at addressing serious pollution in the No. 30106 fully mechanized coal mining face of Shiquan Coal Mine during coal cutting process, the spraying device between hydraulic supports was improved through the combination of experimental analysis, numerical simulation, and field measurement, and a novel wind-assisted centralized spraying dedusting device was developed. The newly developed device could make the formed spraying field more concentrated on the dust-producing source around the coal shearer's drum, and thus significantly enhanced the spraying performance. According to numerical simulation results, the spraying performance reached the optimum at a hydraulic pressure of 8 MPa for the spraying device and an air pressure of 1 MPa for the pneumatic motor; under these optimal conditions, the droplet concentration in the spraying field around the coal cutter drum was as high as 24.85 g/m 3 , and the formed high-concentration spraying field could basically cover the whole section in the spraying field from coal wall to the support pillar. Field measured results revealed that, at a hydraulic pressure of 8 MPa and an air pressure of 1 MPa, the dust suppression rate around coal cutter driver reached up to 87.96%, suggesting that the developed wind-assisted centralized spraying dedusting device had remarkable dust suppression performance and could effectively improve the operating environment in the fully mechanized mining face. Graphical Abstract In this paper, we have designed a novel wind-assisted centralized spraying dedusting device and studied the optimal spray parameters. Firstly, the nozzles were selected according to the multi-factor experimental platform for measuring the spraying field's atomization characteristics. Secondly, we had a numerical simulation of the fully mechanized mining face. And the third, we tested the effect of dust removal.