In shallow overburden area，acquiring geological prospecting information via geological outcrops presents significant challenges.Consequently，there is an urgent requirement for the implementation of geophysical technologies to enhance the optimization of prospecting target areas and the strategic placement of boreholes.Typically，epithermal gold deposits do not directly produce geophysical anomalies.The geophysical properties of gold ore bodies，alteration zones，and their surrounding lithologies remain insufficiently understood.The Alinghe mining area，located within the forested region of northeast China，is characterized by shallow soil cover.The scarcity of rock outcrops has rendered traditional geological and mineral mapping techniques largely ineffective，underscoring the necessity for an increased reliance on geophysical prospecting methods in gold exploration.In response，we conducted high-resolution 1∶5 000 magnetic surveys over areas exhibiting soil gold anomalies，alongside 1∶5 000 induced polarization （IP） measurements using gradient arrays in selected hydrothermal alteration zones.Through the integrated analysis of resistivity and polarizability anomalies，we identified areas with favorable gold mineralization potential.Subsequently，electrical resistivity tomography （ERT） was employed to delineate vertical geological characteristics.In conclusion，verification of drilling and logging activities was conducted.The aforementioned geophysical exploration study yielded the following findings：（1） A series of parallel magnetic anomaly stripes were identified within the andesite distribution area.The observed low magnetic anomalies are attributed to the demagnetization effect resulting from hydrothermal alteration.Hydrothermal activity can reduce the magnetic susceptibility of andesite by up to 1 000 nT.（2） Induced polarization （IP） measurements revealed that the distribution of low apparent resistivity aligns closely with the regions of low magnetic anomalies.The apparent resistivity in the hydrothermally altered area is 100 Ω·m lower than that of the surrounding regions，indicating a water-rich shallow hydrothermal alteration zone.The anomaly of high apparent polarizability suggests a relatively pyrite-rich area associated with epithermal gold ore bodies.（3） Occam’s inversion of electrical resistivity tomography （ERT） data effectively delineates vertical geological features，including surrounding rock，hydrothermal channels，and pyritization zones，which are closely associated with gold mineralization.（4） The geological and alteration assumptions derived from the aforementioned geophysical data were validated by borehole ZK01 along the ERT line，resulting in the identification of two gold-bearing horizons and six gold mineralized bodies within a depth of 100 meters.Through the analysis of curves and crossplots of various logging parameters，the geophysical characteristics of the six gold mineralized bodies were categorized into channel type and terminal type.These two types of gold deposits are distributed on both the upper and lower sides of the high polarizability anomaly，suggesting that a high polarizability anomaly alone is not a direct indicator of a gold ore body，although it holds significant implications for prospecting.In this study，the epithermal gold deposit was systematically targeted for detection.A range of surface geophysical exploration methods was employed to progressively and effectively refine the exploration target area.Subsequent borehole verification confirmed the presence of several gold mineralized bodies，thereby validating the efficacy of the employed methods.The two distinct types of gold-mineralized bodies，categorized based on the combination of geophysical parameters and spatial distribution differences，indicate a terminal position within the mineralization system and suggest minimal erosion post-mineralization.This distinction holds significant implications for the interpretation of geophysical data and has practical relevance for prospecting and exploration efforts.

The shallow orebody located at a depth of 1 500 meters within the Dayingezhuang gold mine in Jiaodong has been extensively delineated.Consequently，exploring the depth range of 1 500 to 3 000 meters is not only essential for providing supplementary resources to support further mine development but also possesses considerable demonstrative value for achieving new breakthroughs in ore exploration.To this end，a 4-kilometer-long multi-polarization electromagnetic sounding profile was conducted at the periphery of the Houtuan area of the Dayingezhuang gold mine.During this study，natural field electromagnetic signals ranging from 1 Hz to 100 kHz were collected.Inversion calculations produced resistivity and magnetization profiles extending to a depth of 3 000 meters.Based on the existing geological prospecting model and the electromagnetic characteristics of Neoproterozoic TTG and Jiaodong Group metamorphic rocks，which exhibit low resistivity and high magnetization，as well as Late Jurassic granite bodies，characterized by high resistivity and low magnetization，the transition zone from low resistance and high magnetization to high resistance and low magnetization is identified as the ore-controlling Zhaoping fault zone，and the expanding space where the dip angle of the fault zone from low-resistivity and high-magnetization to high-resistivity and low-magnetization is interpreted as the ore-controlling Zhaoping fault zone.Additionally，the region where the dip angle of the fault zone becomes more horizontal is inferred to be a favorable site for mineralization.This interpretation is supported by data from drill hole 80ZK2101，which identified a pyrite-silicified alteration zone between depths of 2 943.18 m and 3 108.41 m，with a gold ore body located at depths of 3 100.06 m to 3 101.06 m.The drilling results corroborate the interpretations derived from multi-polarization electromagnetic sounding data.

The northeastern region of Hunan Province，situated within the central Jiangnan Orogenic Belt，is distinguished by the presence of numerous gold deposits，notably including the Wangu and Huangjindong.To systematically investigate the genetic relationships between various fluid-rock interactions and the mechanisms of gold precipitation in this area，comprehensive field geological investigations，petrographic analyses，and thermodynamic simulation have been undertaken.Geological field investigations have identified silty slate as the primary ore-bearing wall rock in northeast Hunan.This rock is notably characterized by extensive bleaching alteration，with ore bodies predominantly situated within the bleached zones.In contrast，certain ore bodies are found within carbonaceous slate，which retains its black coloration and exhibits no visible color change despite undergoing hydrothermal alteration.Petrographic analysis reveals that the bleached zones contain numerous siderite spots，which are intersected by pyrite and arsenopyrite.Conversely，in the carbonaceous slate，sulfide minerals are intimately associated with carbonaceous matter（CM）.The thermodynamic simulation indicates that siderite present in the bleached zone can interact with the fluid，leading to gold precipitation through sulfidation.Similarly，chlorite within slate can also engage with the fluid to initiate sulfidation.However，the dissolution rate of carbonate exceeds that of chlorite，suggesting that carbonate exhibits higher chemical reactivity，which is more conducive to gold mineralization.The carbonaceous matter（CM） in the carbonaceous slate can enhance gold deposition by reducing the fO₂ in the fluid through fluid-rock interactions，facilitating fluid boiling，and providing sites for fluid transport and precipitation.Consequently，the silty slates and carbonaceous slates in northeast Hunan are capable of promoting gold mineralization through distinct mechanisms and are thus favorable wall rocks for gold mineralization.

The Dareer gold deposit， situated within the Gouli mineralized district of the East Kunlun orogenic belt， represents a recently identified small-scale gold deposit. To facilitate deeper exploration and enhance the deposit’s scale， it is imperative to conduct further investigations beyond the preliminary surface studies. The primary halo method is recognized as one of the most direct and effective approaches for this purpose. Consequently， geochemical analyses were performed on 209 samples collected from No.63 exploration line in the area， examining 15 elements including Au，Ag，Cu，Pb，Zn，W，Sn，Mo，As，Sb，Hg，F，Mn，Bi，and Co. Utilizing the R-type cluster analysis method， the study identified the elemental associations characteristic of the deposit. The near-ore halo elements for the AⅡ orebody were determined to be Au，Cu，Pb，Zn，and Ag.The front halo elements were identified as F，Sb，As， and Hg.The tail halo elements were found to be Mo，Co，Bi，Mn，Sn，and W. Utilizing Grigorian calculation methods for axial zoning， the primary halo of the orebody from top to bottom was identified as follows： Zn-W-Hg-Ag-Sn-Cu-Mo-Co-Au-S-Mn-F-Pb-As-Bi. This sequence exhibits distinct characteristics of “coexistence of head and tail halo” and “reverse zoning”with a weak anomalous Au halo present. Based on the deep anomaly features revealed by controlled-source audio-frequency magnetotellurics（CSAMT） inversion in the area，there is significant potential for mineral exploration，sug-gesting the possible presence of blind ore bodies or ore bodies extending deeper into the earth. In light of the geophysical and geochemical characteristics， deep drilling verification was conducted on the No.55 and No.71 exploration lines， flanking the No.63 exploration line. This led to the discovery of orebodies with the highest grade reaching 27×10^-9，thereby achieving excellent prospecting results and confirming the efficacy of the research methods employed.

The Dayingezhuang gold deposit， located in the northwest of the Jiaodong Peninsula， is characterized as an altered rock-controlled gold deposit. Gold mineralization predominantly occurs within the beresitization alteration zone situated in the footwall of the Zhaoping fault zone. The reddenization alteration is observed in the Mesozoic granitoid， whereas chloritization alteration is present in the metamorphic wall rocks of the Jiaodong Group. Despite these observations， the impact of various alteration conditions on gold mineralization， the migration pathways of ore-forming fluids， and the spatial dynamics of water-rock interactions that lead to gold precipitation remain inadequately understood. This study employs the TOUGHREACT software to simulate the chemical interactions between ore-forming fluids and wall rocks at different stages of the Dayingezhuang deposit. The simulation aims to quantitatively analyze the redox and acid-base properties associated with distinct alteration processes and to examine the chemical equilibrium concentrations of gold （Au） along with the volume fractions of key altered minerals at various stages. The simulation results indicate that during the primary mineralization stage， the pH value of the fault zone is below 7， and the lgf（O₂） decreases from -27 to -44， suggesting acidic conditions with low oxygen fugacity. In contrast，the pH value in the Jiaodong Group and Linglong granites exceed 7，with lgf（O₂） values ranging from -30 to -40， indicating alkaline conditions with higher oxygen fugacity. The volume fraction of pyrite and sericite near the fault zone varies from 0 to +0.025%， while the volume fraction of chlorite in the Jiaodong Group metamorphic rocks ranges from 0 to +0.01%. The volume fraction of potassium feldspar in the Linglong granites varies from 0 to +0.05%. These findings suggest that the alteration system surrounding the Dayingezhuang gold deposit functions as a conjugate reaction system， characterized by contrasting redox and acid-base properties. Chloritization and reddenization alterations occur under oxidative and meta-alkaline conditions. The spatial distribution of gold precipitation is predominantly located near the fault zone. As the ore-forming fluids migrate， beresitization alteration occurs under reductive and acidic conditions， leading to the formation of gold orebodies.

The prediction of goaf stability is a critical component of mine safety management.Accurate forecasting of goaf stability during mining operations is essential for ensuring both the safety and environmental integrity of mining activities.Due to the intricate nonlinear relationship between goaf stability and its influencing factors，traditional prediction methods often fall short in delivering precise results.Machine learning，however，is well-equipped to address this issue.To overcome the challenges of algorithms becoming trapped in local optima and exhibiting suboptimal convergence speed and accuracy，a stability prediction model for goaf，based on the SIDBO-BP algorithm，was proposed to effectively classify and predict the stability of mine goafs.In light of the internal and external factors influencing goaf stability，nine specific factors were identified based on the unique conditions of the mine：Burial depth （X1），exposed roof area （X2），high collapse ratio （X3），goaf volume （X4），goaf dip angle （X5），conditions of adjacent goafs （X6），rock compressive strength （X7），geological structure （X8），and rock mass structure （X9）.These factors were utilized to classify the stability status of four goafs，which served as output levels in the construction of a goaf stability prediction model. The study utilized ninety-three datasets from a lead-zinc mine in Yunnan as the research object.Correlation and visualization analyses of the goaf data were performed using graphical correlation analysis and correlation coefficient graph methods，thereby validating the appropriateness of the selected factors.The goaf data were normalized using MATLAB.Subsequently，the SIDBO algorithm was applied for optimization，yielding the optimal position and fitness，which were then employed in a BP neural network to determine the optimal threshold weight for prediction.The macro-average method was employed to compute the metrics of accuracy，precision，specificity，recall，and F1 score for the predictive outcomes.The model’s predictions were assessed and benchmarked against those generated by other algorithmic models.The findings revealed that only a single prediction from the SIDBO-BP model was inaccurate.The SIDBO-BP model demonstrated superior accuracy，precision，specificity，recall，and F1 score compared to the other algorithmic models，aligning closely with the actual results.Additionally，its overall performance exceeded that of the other five models.These results suggest that the SIDBO-BP model provides substantial advantages in terms of prediction accuracy，convergence speed，and the avoidance of local optima.

To investigate the effect of polypropylene fiber doping on the tensile properties of tailings cemented filling materials，Brazilian splitting experiments were conducted on tailings cemented filling materials with different ash-to-sand ratios and polypropylene fiber contents.DIC technology was used to observe and analyze the initiation and propagation evolution of surface cracks on the specimens during the experiment，and scanning electron microscopy （SEM） was used to reveal the mechanism of the reinforcing effect of polypropylene fibers on the internal structure of tailings cemented filling materials.To examine the impact of polypropylene fiber incorporation on the tensile properties of tailings cemented filling materials，Brazilian splitting tests were performed on samples with varying ash-to-sand ratios and polypropylene fiber contents.Digital Image Correlation （DIC） technology was employed to observe and analyze the initiation and propagation of surface cracks on the specimens throughout the experiment.Additionally，scanning electron microscopy （SEM） was utilized to elucidate the mechanism by which polypropylene fibers enhance the internal structure of the tailings cemented filling materials.The findings of the study indicate that incorporating polypropylene fibers significantly enhances the uniaxial tensile strength of the filling material.As the polypropylene fiber content increases，the uniaxial tensile strength initially rises and subsequently declines，with an optimal fiber content identified at 0.6%.For instance，with an ash-to-sand ratio of 1∶4，the maximum uniaxial compressive strength of the filling specimen reaches 0.59 MPa，representing a maximum increase of 37.21%.Furthermore，the inclusion of fibers alters the stress-strain characteristics of the filled specimen.Upon reaching peak tensile strength，the PF-filled specimen did not immediately experience a loss in load-bearing capacity and retained a degree of residual strength.Notably，the residual strength of the specimen filled with 0.6% PF attained its highest value.Observations using Digital Image Correlation （DIC） technology reveal that the strain concentration phenomenon in fiber-reinforced fillers is mitigated during tensile failure，resulting in more tortuous crack patterns.This indicates that the fibers effectively facilitate stress dispersion.Scanning Electron Microscopy （SEM） analysis indicates that an excessive incorporation of fibers results in the enlargement of pores and cracks within the filling body specimen，consequently leading to a gradual reduction in its macro compressive strength.Conversely，an optimal quantity of fibers becomes encapsulated by a substantial amount of hydration product，specifically calcium-silicate-hydrate （C-S-H） gel，within the specimen.This encapsulation facilitates the integration of the fiber-filling body matrix interface into a cohesive unit due to the influence of the C-S-H gel，thereby enhancing the load-bearing capacity of the fiber-reinforced filling body.

Digital Image Correlation （DIC） technology facilitates non-contact，real-time monitoring and analysis of the dynamic mechanical behavior of materials by tracking speckle patterns on the surface of samples.Nevertheless，in the context of Split Hopkinson Pressure Bar （SHPB） testing，characterized by high strain rates and complex loading conditions，DIC technology encounters several challenges，including limited measurement accuracy and inadequate adaptability to environmental variations.In order to fully grasp the application status and optimization methods of DIC technology in SHPB test，based on the principle of SHPB test and DIC technology，the relevant research results on the improvement of large deformation measurement accuracy were summarized from the aspects of incremental correlation，shape function，initial value estimation and deep learning algorithm.Subsequently，based on the specific requirements of SHPB tests， practical optimization strategies for DIC technology were proposed， focusing on speckle fabrication techniques and material mechanical characteristics feedback.These strategies include the utilization of high-speed cameras and the optimization of image processing algorithms to improve the efficacy of the image acquisition and processing system.Additionally，efforts are made to augment the environmental adaptability of DIC technology，ensuring its stable operation in challenging conditions such as high temperature and high pressure.Combined with other testing methodologies，the implementation of multi-parameter measurement and comprehensive analysis facilitates a more thorough understanding of the dynamic mechanical behavior of materials.The application and optimization of DIC technology in SHPB testing are intended to enhance measurement accuracy，broaden the scope of applications，and advance the intelligence of the testing system.This approach is expected to yield more precise evaluations of the dynamic mechanical properties of materials，thereby providing substantial support for advancements in materials science and related engineering disciplines.

In natural settings，rock masses frequently contain various fissures that may exhibit parallel orientations，significantly influencing their mechanical properties.These fractured rock masses are continuously exposed to static loads，such as the weight of overlying rock in subterranean environments，as well as dynamic loads resulting from activities like drilling and blasting.The interaction between these loads and the rock mass is crucial for determining the stability of the rock mass，particularly in underground and mining contexts.This paper seeks to investigate the dynamic characteristics，energy dissipation，and damage mechanisms of parallel-fractured sandstone under cyclic impact testing at varying confining pressures （4，8，12，16，20 MPa），utilizing the Split Hopkinson Pressure Bar （SHPB） for experimentation.The primary aim of this study is to examine how cyclic loading affects the dynamic response and damage evolution of fractured rock masses.The experimental design involves subjecting parallel-fractured sandstone specimens to multiple impact cycles，with confining pressure varied across different levels.The results of the cyclic impact tests indicate that，under a constant confining pressure，the dynamic peak stress of fractured sandstone progressively decreases as the number of cycles increases.The relationship between peak stress and the number of cycles is found to be linearly negative，demonstrating a consistent reduction in the rock’s capacity to endure dynamic loading over time.Furthermore，the study explores the effects of varying confining pressures on the dynamic behavior of fractured sandstone.The findings reveal that as confining pressure increases，the peak stress initially rises and subsequently declines，suggesting that moderate confining pressures enhance resistance to dynamic loading.The maximum number of cycles required to reach failure occurs at a confining pressure of 12 MPa，indicating an optimal confining pressure for the sandstone’s resistance to cyclic impact prior to failure.This observation underscores the critical role of confining pressure in regulating damage accumulation and failure processes in fractured rock masses.Additionally，the study investigates energy dissipation during the cyclic impact process.Throughout the duration of the test，the proportion of reflected energy exhibits a continuous decline，decreasing from 27% to 12%，which constitutes a reduction of approximately 15%.Conversely，the proportion of transmitted energy demonstrates a steady increase，ranging from 41% to 55%，indicating an increase of 14%.The proportion of absorbed energy remains relatively stable，fluctuating between 33% and 35%，with minimal influence from variations in both confining pressure and the number of cycles.This consistent behavior of absorbed energy implies that the intrinsic energy absorption capacity of fractured sandstone remains stable regardless of the loading conditions.The progression of damage in fractured sandstone is also a central focus of this study.Cumulative damage increases progressively with the number of cycles，with the maximum cumulative damage recorded under cyclic impact at confining pressures of 4 to 16 MPa ranging between 0.137 and 0.165.The highest cumulative damage （0.165） is observed at a confining pressure of 4 MPa，whereas the lowest damage （0.092） is noted under a confining pressure of 20 MPa.The findings of this study indicate that lower confining pressures expedite the accumulation of damage，whereas higher confining pressures lead to a more gradual progression of damage.The research concludes that the rate of damage accumulation in fractured sandstone is accelerated during the initial impact phase and as failure approaches.Importantly，the damage incurred during a single impact is relatively substantial，underscoring the necessity of regulating both confining pressure and cyclic impact cycles to mitigate excessive damage and prevent premature failure.These results provide valuable insights into the dynamic behavior of fractured rock masses under cyclic loading，offering practical guidance for assessing the stability of underground rock masses subjected to similar loading conditions，such as those encountered in mining or tunneling operations.

As a representative example of an urban mining operation，the Meishan iron mine produces significant blasting-induced vibrations throughout its production activities.Unlike blasting operations in construction projects such as tunnels and subways，those at the Meishan iron mine involve substantial quantities of explosives and occur at considerable depths below the surface.Therefore，it is essential to examine the response characteristics of blasting vibrations on the high-rise buildings in the vicinity of the mine.The nearest high-rise structure to the Meishan iron mine is located immediately west of the production zone and comprises a 28-story residential building.The spatial separation between the ground floor lobby of this building and the closest production operation area is approximately 300 meters in both horizontal and vertical dimensions.On-site monitoring yielded five sets of valid data.An analysis of the data revealed that the peak vibration velocity in the high-rise building was observed at an elevation of H=30 m，corresponding to the 11th floor.While no general amplification effect of blasting vibrations was detected，a localized amplification phenomenon was identified at the top floor.In examining the three-dimensional characteristics of blasting vibration waves，it was determined that vertical vibrations had the most significant impact on the overall vibration，exhibiting a localized amplification effect at the top floor.In the pursuit of pertinent research on vibration mitigation，it is imperative to prioritize the attenuation of vertical vibrations.Utilizing on-site monitoring data，the propagation of blasting-induced vibration waves within this structure was simulated through the application of Midas GTS NX software.The simulation model was subjected to loading by incorporating the vibration waves recorded at the base of the building model.A time history analysis approach was employed for computational purposes.Upon completion of the calculations，data from each measurement point were systematically extracted for further analysis.The study demonstrated that the acceleration waveforms at each measured point，as derived from this simulation method，closely aligned with the input waveforms.The discrepancy between the maximum vibration velocity and the empirical data was minimal，and the trend of variation corresponded well with the observed data.These findings indicate that the simulation method exhibits a high degree of accuracy in these scenarios and offers an innovative approach for investigating the blasting vibration response characteristics of high-rise buildings.

The particle size of minerals is a critical parameter influencing flotation recovery.An optimal particle size range can significantly enhance flotation recovery，whereas excessively coarse or fine particles tend to diminish recovery rates.In conventional mechanical agitation flotation cells，mineralization predominantly occurs in the vicinity of the impeller.Consequently，the rotational speed of the impeller dictates the turbulence dissipation rate within the tank and the size of the bubbles produced.The simultaneous recovery of both fine and coarse particles poses a significant challenge for mechanical agitation flotation machines.The aerated jet flotation cell，which incorporates an air micro-pore foamer and a small-diameter nozzle，represents an advancement over the conventional Jameson flotation cell，offering improved equilibrium in the flotation recovery of coarse and fine mineral particles.To examine the enhancement effect of the aerated jet flotation cell on the flotation process of finely disseminated lead sulfide，a specific lead sulfide ore was selected as the focus of this study.The primary operational parameters，including aeration flow，pulp flow，and bottom pulp flow，were systematically analyzed to assess their influence on the flotation index.Results from flotation tests on a specific lead sulfide ore demonstrate that，in comparison to conventional mechanical agitation flotation cells，the aerated jet flotation cell enhances the overall lead recovery in the concentrate.Additionally，it increases the recovery rates of coarse particles （+0.074 mm） and fine particles （-0.025 mm） by 12.47% and 11.39%，respectively.Utilizing fluid dynamics software，the study examined the impact of varying parameters on the probabilities of collision，adhesion，and detachment between particles and bubbles.The findings indicated that an increase in particle size，pulp flow，and aeration flow corresponded with heightened probabilities of collision and detachment.Conversely，the probability of adhesion diminished with an increase in particle size.Specifically，for particles with a diameter of 0.025 mm，the probability of adhesion decreased as both pulp flow and aeration flow were augmented.The simulation analysis demonstrates that the results align with the experimental findings.The aerated jet flotation cell markedly diminishes turbulence kinetic energy within the tank by reducing bubble size and enhancing the turbulence dissipation rate in the mineralized pipe and nozzle regions.This process establishes distinct zones within the tank：A strong turbulence zone，a transition zone，and a weak turbulence enrichment-separation zone.Consequently，the flotation recovery rate of both coarse and fine lead minerals is significantly enhanced.

Investigating the impact of Ca²⁺ and Mg²⁺ ions within the sodium oleate system on the flotation effi-cacy of pyrite offers valuable insights for the reverse flotation separation of pyrite from carbonate minerals in carlin-type gold ore utilizing sodium oleate.Results from single-mineral flotation experiments demonstrate that both Ca²⁺ and Mg²⁺ ions enhance the flotation of pyrite in the sodium oleate system.Under identical pH value conditions，Mg²⁺ exhibits a more significant activation effect on pyrite compared to Ca²⁺.When the pH value is less than 11，the adsorption of Ca²⁺ onto pyrite results in a gradual decrease in the recovery rate as the pH value increases.Similarly，when the pH value is less than 10，the adsorption of Mg²⁺ also leads to a decrease in the recovery rate of pyrite with increasing pH value.However，the recovery rate increases again when the pH value is equal to or greater than 10.Evidence from contact angle measurements，solution chemistry analyses，and scanning electron microscopy indicates that at lower pH value levels，calcium predominantly adsorbs onto the pyrite surface in the form of Ca²⁺.This calcium then reacts with oleate ions in the solution to form calcium oleate，which coats the pyrite surface，thereby increasing its surface contact angle and enhancing its hydrophobicity.Magnesium is adsorbed onto the pyrite surface as Mg²⁺ ions，which subsequently react with oleate ions to form magnesium oleate.This formation enhances the surface contact angle of pyrite，thereby increasing its hydrophobicity and improving its flotation rate.Analysis through infrared spectroscopy and X-ray photoelectron spectroscopy（XPS） further reveals that the presence of Ca²⁺ and Mg²⁺ on the pyrite surface results in the appearance of calcium and magnesium elements.This presence enhances the adsorption of sodium oleate on the pyrite surface，consequently influencing the flotation rate of pyrite.As the pH value increases，the Fe-S bonds on the surface of pyrite dissociate，resulting in the formation of hydrophilic Fe（OH）₃ and SO₄⁻，which subsequently form a hydrophilic film on the pyrite surface.This film inhibits the adsorption of ions and collectors.Additionally，Ca²⁺ and Mg²⁺ ions undergo changes in their valence states due to the elevated pH value，leading to a decrease in their adsorption concentration on the pyrite surface and diminishing their activation ef-fect.Therefore，if sodium oleate is used to separate pyrite and carbonate minerals，the removal of Ca²⁺ and Mg²⁺ from the solution should be considered to reduce ion adsorption on the surface of pyrite and strictly control the pH value to reduce the activation effect on pyrite.

As mining operations progressively transition to deeper levels， the production conditions within mines become increasingly complex and challenging. This necessitates an advancement in the sophistication of intelligent equipment and a gradual reduction in on-site personnel.Developing an efficient and precise sche-duling and control system that aligns with these requirements is essential for ensuring intelligent mining ope-rations.Consequently，this study concentrates on optimizing the scheduling of underground gold mines， characterized by multiple equipment and short interval continuity，to enhance mining efficiency and safety.The limitations associated with multi-process， multi-equipment， and intricate coupling in underground gold mining operations have been systematically analyzed and distilled， leading to the formulation of a comprehensive set of scheduling requirements.By developing a combinatorial optimization model for equipment configuration and task allocation， the issue of underground equipment scheduling is conceptualized as a flow shop scheduling problem， with the objectives of minimizing the total duration and the total intervals.A genetic algorithm is utilized to address the model， facilitating dynamic and precise scheduling of mining equipment through short interval adjustments， thereby minimizing task conflicts and equipment idle times.The results of the case study demonstrate that the optimized model can significantly reduce overall operation durations and process intervals across diverse operational scenarios. In large-scale production settings with multiple cycle constraints， a mining efficiency of 72.57 tons per hour is attained.Furthermore， with an 8% failure rate， the delay in total operation time is maintained within 15%.The configuration of scientific equipment and the development of scheduling strategies are crucial for augmenting the production capacity of mining operations.The findings of this study offer an optimized solution for equipment scheduling in underground gold mines， thereby improving overall operational efficiency and safety while ensuring continuous production.

Underground metal mining operations are complex，involving dynamic events，parallel processes，and strict time-space constraints.These operations require the coordination of multiple independent mining equipment，，and process entities to ensure efficient ore extraction.Accurately modeling these operations and replicating the scheduling process iscrucial for optimization.Converting the physicalmining processes into a virtual environment is vital for effective simulation and modeling.This paper introduces a Petri net-based method for modeling and simulation，creating a framework that maps underground mining systems to a simulation space，facilitating dynamic scheduling of mining equipment.The construction of the mining system employs a five-layer architecture for hierarchical planning，establishing a structured framework for the mining operation system.This framework encompasses elements such as thematic domain grouping，thematic domains，business objects，logical entities，and attributes.Fundamentally，the mining operation system is characterized by the dynamic interaction of multiple entity objects across three primary thematic domains：Mining operation space，mining operation equipment，and mining operation processes.Utilizing Petri nets，the interrelationships between theoverall system and its constituent parts，as well as the interactions among components within localized areas，arethoroughly delineated.This approach facilitates the demonstration of event sequences，parallelism，synchronization，and asynchronous characteristics during the mining operation process.It also highlights conflicts，mutual exclusion，uncertainties，and potential deadlock issues within the system，thereby enabling a comprehensive analysis and evaluation of the system.The Generalized Stochastic Petri Net（GSPN） methodology is utilized to model transitions as random variables governed by mathematical distributions，thereby addressing the intricate coupling issues among space，equipment，and processes within the mining operation system.This approach facilitates the assessment of the system’s performance and reliability，yielding key production evaluation metrics such as production efficiency，equipment utilization，and effective working time.A practical simulation，based on an idealized data set constructed in accordance with the standard design stope of the Chambishi copper mine，serves to validate the mining operation system.The simulation results indicate that the total operation progress completion time is 213.77 days，during which 656 mining operation records，are generated.Additionally，a mining operation Gantt chart is constructed to illustrate the operation cycle and strip succession.The findings of this research provide robust support for dynamic scheduling decisions in underground metal mining operations，contributing to the achievement of efficient，safe，and intelligent mine production management.

The smart mining serves as the core engine of the digital transformation in the mining industry. By reviewing the latest global R&D and application advances，this study systematically investigates how key technologies empower the smart development of mining operations.Key technologies play a pivotal role in advancing the smart mining industry，with a primary emphasis on addressing practical production requirements.Research areas encompass the Internet of Things，machine vision，machine hearing，deep learning，big data mining，intelligent sensors，collaborative robots，digital twins，and green mining，among others.The application scenarios within smart mines predominantly involve intelligent control systems，asset management，safety assurance and its associated systems，data management and analysis systems，and monitoring systems.In anticipation of future advancements，the innovation and integrated application of key technologies are poised to serve as the central catalyst for the holistic development of smart mining，emphasizing high quality，sustainability，and enhanced intelligence.By leveraging artificial intelligence and big data technologies，the comprehensive capabilities of mines，such as precise exploration，optimization of mining pathways，reduction of energy consumption and waste，and improvement in resource utilization efficiency，will be significantly enhanced.The integration of digital twins and artificial intelligence is poised to facilitate the comprehensive digital operation of mining enterprises.Complementary technologies，including blockchain，the Internet of Things，cloud computing，and 5G，will enhance the efficiency and precision of remote management and intelligent decision-making processes within the mining sector.This technological synergy will establish a robust foundation for the transformation and modernization of the industry，steering it towards more sustainable，safe，digital，intelligent，and efficient practices.

In the context of the global rare earth supply dynamics，it is of strategic importance to identify and analyze the driving factors influencing the value chain reconstruction of China’s rare earth industry to ensure the security of the nation’s industrial and supply chains.Utilizing the theoretical framework of national competitive advantage and employing the DEMATEL-ISM model，this study identifies and categorizes the driving factors impacting the reconfiguration of the rare earth value chain.The findings of this study can be summarized as follows：（1） Rare-earth enterprises have historically occupied a position at the lower end of the industrial value chain，which constitutes the fundamental factor influencing the reconfiguration of the value chain within China’s rare-earth industry.（2） The primary drivers affecting the reconstruction of the value chain in the rare-earth sector include the intrinsic motivation of rare-earth enterprises，the imbalance in the supply and demand structure of rare-earth materials，the stringent requirements imposed by dual carbon goals on the industry，and the scarcity of highly skilled professionals specializing in high-end rare-earth technologies.（3） The sustainability of rare earth resource development，the control over both ends of the rare earth value chain，and the significant military and economic importance of rare earths amidst geopolitical competition among major powers are fundamental factors influencing the restructuring of the rare earth industry value chain.In pursuit of this objective，it is essential to expedite the development of advanced productive capacities in the rare earth sector，establish a high-quality modern industrial system for rare earths，and further enhance the sector’s openness to international markets.A comprehensive assessment of the strategic value of rare earths is required，alongside increased policy support，to facilitate the restructuring of the value chain and promote the high-quality development of China’s rare earth industry.

Rare earth elements are essential raw materials that underpin strategic emerging industries，including those focused on new energy，advanced materials，and high-end technological innovation.Consequently，they have emerged as vital strategic mineral resources subject to global competition.In the context of the current wave of technological revolution and industrial transformation，the security of the rare earth supply chain is encountering unprecedented and complex challenges，largely due to its significant international geopolitical implications.A scholarly assessment of the resilience of the rare earth industrial chain aids in elucidating the existing impediments to the development of China’s rare earth industry and facilitates a comprehensive and precise understanding of its current resilience status.Utilizing pertinent data spanning from 2000 to 2022，this thesis develops an indicator system to measure the resilience of the rare earth industrial chain across four dimensions：Resistance，recovery，reorganization，and renewal capabilities.The entropy weight method was utilized for evaluation，and a subsequent analysis of the comprehensive resilience score was performed using the index obstacle degree model，the index contribution model，and the coupling coordination degree model.The results indicate that：（1） The resilience of China’s rare earth industrial chain exhibited an upward fluctuation from 2000 to 2022.（2） Prior to 2016，the primary impediment to resilience in the rare earth industry chain was the renewal capability，whereas post-2016，the resistance capability emerged as the predominant constraint.（3） The enhancement of resilience within the rare earth industrial chain is predominantly influenced by recovery and renewal capabilities.（4） Between 2000 and 2022，the coupling coordination level among various resilience indicators of the rare earth industrial chain has shown an upward trend，albeit remaining imbalanced.The findings of this study offer policy insights for strengthening the resilience of China’s rare earth industry chain，with recommendations for countermeasures at the enterprise，industry，and government levels.