The Paishanlou gold deposit is located in the gold province of northern margin of North China Craton，which is the third largest gold province in China.The deposit is mainly hosted in metamorphic rocks of the Jianping Group of Archean and it is structurally controlled by two sets of ductile shear zones.Both the Paishanlou gold deposit in Liaoning Province and Hetai gold deposit in Guangdong Province were firstly been confirmed as ductile shear zone type gold deposits in China.The main orebody T4 in the mining area is controlled by the northeast trending ductile shear zone，and the host rocks are the biotite-plagioclase mylonite and felsic mylonite from Late Archean Jianping Group.The orebody lies in the most strongly deformed rocks in the ductile shear zone，and its hanging wall is dolomitic mylonite.Previous studies have shown that dolomitic mylonite plays a role as a geochemical barrier in the mineralizing process.The Yanshanian granite intruded into the ore-bearing Jianping Group.In this study，by summarizing the geological characteristics and main ore-controlling factors of the Paishanlou gold deposit，it is believed that the ductile shear zone in the area is a rock-controlling and ore-controlling structure，which controls the spatial distribution of the ore-bearing mylonite and gold ore bodies.Granite intrusion causes thinning of ore-bearing rocks which reduced prospecting space.The grade and thickness data of the ore-body T4 were collected in this study.By using the Surfer software to compile the grade and thickness contour maps，the distribution characteristics of the grade and thickness of the ore-body T4 were analyzed.It is considered that the grade and thickness of the ore-body T4 from the east end near the surface to the deep end of the west end can be divided into three obvious gradient zones，and the grade and thickness gradually decrease.The thickness and grade of the orebody shows spatially high consistency.According to the gold grade contour map，we judge that the orebody is leaning to the south and west，with a side leaning angle of 53°.It indicates that the thickness and grade of the orebody T4 in the southwest of the deep have a significant decrease.Therefore，there is no great potential to find economically important orebody in the southwest of the deep.It’s proposed to analyze and research the prospecting potential of other ductile shear zones in the mining area.
The planation surface formation and its distribution have the characteristics of long-time span and wide distribution range， which is the basic content of geomorphology research.In order to discuss the relationship between the preservation of porphyry copper deposits after mineralization and the planation surface， based on geographic information system（GIS）platform，the paper extracted various geomorphic factors，such as the elevation，the slope and swath profile from digital elevation model（DEM）data，and then the elevation and distribution range of the planation surface were defined in the Zhongdian region.The Zhongdian region is located at the southeastern Tibetan Plateau.In this paper，DEM data from National Aeronautics and Space Administration（NASA） were used to calculate the slope value of 0°~61° in Zhongdian region by GIS technology platform，and the areas with low slope value（0°~10°）were reclassified.Meanwhile，the profile elevation of the Zhongdian region is accurately depicted by using the strip profile，and then the elevation values of the planation surface （+4 100~+4 400 m and +3 100~+3 300 m） and the topographic relief were visually displayed，indicating the distribution height of the planation surface in Zhongdian region.In this study，the thermal history of the typical porphyry（such as Xuejiping complex）was simulated，and the cooling and denudation history of the complex were reconstructed，and the cooling curve were obtained.The results show that the slope distribution in Zhongdian region was concentrated in two planation surfaces between 0° and 10°，revealing the characteristics of the high elevation and low topography.The Xuejiping complex experienced a prolonged slow cooling from the Upper Cretaceous to Late Miocene（<1 ℃/Ma），and the denudation extremely low（500~950 m），reflecting the tectonic quiet period.The process suggests that the planation surface was formed earlier than Late Cretaceous and finally in the Miocene.Combined with the former research results，the widely distributed planation surface in Zhongdian area provides favorable paleogeomorphologic conditions for the preservation of Late Triassic porphyry deposits.As the same time，the cooling history of porphyry deposits also describes the formation process of planation surface，and there is a certain coupling relationship.The existence of planation surface in Zhongdian region not only directly provides geomorphological evidence of surface uplift，but also further supports the stepwise uplift geodynamic model of the southeastern Tibetan Plateau.
Three-dimensional geological modeling can be divided into traditional wireframe modeling and implicit modeling.Compared with traditional wireframe modeling，implicit modeling method does not require a large number of human-computer interactions，and has the advantages of high model quality，repeatable process and fast local dynamic update speed.After years of research，various interpolation methods for implicit modeling have been developed，but the constraint data required for implicit modeling interpolation requires a lot of preprocessing，for a wide range of geological modeling work，manual processing of interpolation constraint data requires a lot of time and energy for geologists，and the operation of geological modeling based on manual processing is semi-automatic implicit modeling.In order to improve the automation degree of geologic body implicit modeling method，we proposed a method of automatic extraction and quantification of formation characteristic parameters based on borehole data，which can take into account the global occurrence characteristics of stratum and the local occurrence trend of borehole，and be used to construct interpolation constraints that control the geometry of different geological interfaces.This method analyzes the original geological drilling data，automatically extracts the occurrence of the formation to characterize the global interpolation trend of the formation，and then uses the local ellipsoid search to construct the neighborhood drilling group，extracts the field boundary point set according to different search strategies，and finally calculates the local occurrence parameters to construct local interpolation trends.Based on the above ideas，combined with the implicit modeling method of geological bodies considering the constraints of stratigraphic sequence，a complete geological body model that conforms to stratigraphic characteristics and satisfies the laws of stratigraphic sequence was constructed.The data extracted by this method were used to construct a single geological model of a uranium deposit in Xinjiang using the potential field method and the HRBF method，after that，a comprehensive model of complex shapes was constructed with full consideration of the constraints of geological rules.Comparison of the geometric form of a single model built by the two interpolation methods and the comparison of the exploration line profile of the overall model，the research results show that the new method takes into account the geological rules and constraints，can simulate sedimentary strata and intrusions strata well，and the model has good accuracy and conforms to the cognitive rules of geologists.
During the mining of underground mineral resources，the deep hard rock will be damaged by the frequent stress disturbances.Its internal pores and fissures will rapidly expand and penetrate under the state of high ground stress and high osmotic pressure，which seriously threatens the safety and stability of rock mass engineering.The damage degree D is defined by the ratio of axial stress σ to compressive strength σc.Pre-damaged rock samples with different damage degrees （0%，25%，40%，50%，65%，75%，100%） were prepared by uniaxial compression test.A series of stress-seepage coupling tests were carried out for 75% damaged granite.Combined with CT scanning，considering the influence of seepage pressure，confining pressure and damage degree，the mechanical and seepage characteristics of damaged rock under stress-seepage coupling was comprehensive analyzed.The research results show that with the increase of damage degree，the number and size of pore and fracture of rock sample increase significantly，and changes of the volume of pore and fracture of rock sample shows a trend of increase gently and increase steadily to increase sharply.Under the same confining pressure，the peak strength of the rock sample shows a linear decrease with the increase of osmotic pressure，the osmotic pressure has a significant weakening effect on the strength of damaged granite，and the degree of weakening is independent of the confining pressure.The permeability of pre-damaged rock samples is closely related to the volume of pores and fractures.The variation trend of permeability with damage percentage confirms the evolution law of pores in different development stages.The greater the degree of damage，the higher the degree of fracture development and the greater the permeability.At the same time，the permeability can be characterized by the degree of development of pores and fractures.With the same degree of fracture development，the greater the confining pressure，the smaller the permeability.
Sublevel caving method without sill pillar is gradually applied to mining of inclined medium-thick ore bodies，for it has the advantages of simple craft，safety，high efficiency，high mechanization and low mining cost.Nevertheless，its high ore loss and high dilution in the mining of the inclined medium-thick orebody are still ubiquitous，so the inserts drawing technology was proposed.The basic principle of this technology is to insert steel pipes at the contact point of drift to form a diversion isolation plate （inserts） to change the flow path of the ore and the rock，and also to improve the conditions of drawing.By adopting inserts drawing technology，12 sets of physical simulation experiments of inserts drawing were carried out to analyze the influence of different sizes of drawing point on the ore loss and dilution of inserts drawing technology.The experimental results show that when the following drawing indexes are determined，such as the orebody inclination，orebody thickness，sublevel height and ore caving interval，and the inserts drawing technology is adopted，with the same height of the drawing point，the ore recovery rate increases with the augment of the width of the drawing point accordingly，and the dilution rate does not change significantly with the increase of the width of the drawing point.With the same width of the drawing point，the ore recovery decreases as the height of the drawing point increases，while the dilution rate increases with the increase of the height of the drawing point.Under the condition of the same dilution rate，compared with the conventional drawing，the recovery rate of inserts drawing is increased by 28.33%.In the process of drawing，the width of drawing point is increased，and the inserts structure can effectively change the original flow path of the waste rock，delay the flow rate of the waste rock，and prevent the waste rock from being prematurely depleted.The drawing scheme with a height of 3 m and a width of 6 m has the best drawing effect，and the ore recovery rate is 73.61%.
The unconventional failure phenomenon of rocks，such as slabbing and rock burst，occur frequently in deep engineering，which bring huge financial loss and casualties.The occurring mechanism of the un-conventional failure is still unclear，and the stress state and levels of rocks is the main factors inducing unconventional failure.The surrounding rocks of deep engineering is under a one-dimensional，two-dimensional or three-dimensional stress conditions，corresponding to the stress state of the rock specimen in the uniaxial，biaxial or true triaxial compression tests，respectively.In this study，the uniaxial，biaxial or true triaxial compression tests were carried out to reveal the occurring terms of the unconventional failure of rocks.The isolated ore pillars left after room-pillar mining are usually under one-dimensional compressive stress.Through uniaxial compression tests of rock specimens with different height-width ratios and width-thickness ratios，it is found that the strength of rock specimen exhibits obvious characteristics of non-linear changes as the height and width of rock specimen increase.As the thickness increases，the uniaxial compressive strength increases.As the height increases，the uniaxial compressive strength tends to increase first and then decrease.This is mainly related to the slabbing failure of the dwarf and thin rock specimens.Combining the uniaxial compression test of cuboid rock specimens and the reduction of rock mass mechanical parameters，the safety evaluation of the isolated pillars can be conducted.Based on the fact that the surrounding rocks of underground engineering are often under a two-dimensional stress state，and the fact that rocks far away from the boundaries of underground engineering are often under a three-dimensional stress state，the biaxial compression and true triaxial compression tests of cubic rock specimens have been carried out.The rock strength in biaxial or true triaxial test shows obvious intermediate principal stress effect.Under the same minimum principal stress，the biaxial compressive strength and true-triaxial compressive strength of rocks increases first and then decreases with the increase of the intermediate principal stress，and the change rate of biaxial compressive strength decreases firstly and then shows a little increase.An exponential rock strength criterion was constructed by defining the strength increment parameter ν and the intermediate principal stress position parameter λ.It is considered that low confining pressure limitation，asymmetric confining pressure limitation and short crack propagation path are the main terms for unconventional failures of rocks under multi-dimensional stress conditions.
As a difficult point in rock mechanics，end effect has been widely concerned by scholars.The phenomenon of end effect is caused by the friction between the indenter of testing machine and rock specimen in the process of compression，which usually causes the measured compressive strength of rock increased.However，the more intuitive performance of end effect is that the radial strain of rock is larger in the middle and smaller at both ends.According to Saint-Venant’s principle，when the height diameter ratio is greater than 2.0，the influence of the end effect can be ignored，but only the influence of the end effect on the measured uniaxial compressive strength can be ignored，which doesn’t form uniform stress in the specimen.Therefore，the method of weakening the end effect should be further studied.By summarizing the research of domestic and foreign scholars，it is found that there are two main methods to reduce the end effect，they are reducing the end friction and controlling the end deformation.The first method is to add friction reducing agent between the indenter of the testing machine and the end of the rock specimen，but it can’t completely eliminate the end effect.The second method is to use the metal specimen with the same mechanical parameters as the rock specimen as the cushion block，but it is too difficult to find this kind of metal material.Based on the second idea，to reduce the influence of end effect in the measurement of uniaxial compressive strength，a new uniaxial compression test method was proposed.In this method，uniaxial compression test was carried out using the rocks with the same material as the specimen as the cushion block.Two combination forms of （25+50+25）mm and （20+60+20）mm are set for the experiment，and the experimental results are compared with those specimens with the height of 50 mm and 60 mm.The results show that the new experimental method can reduce the influence of end effect on the measurement of uniaxial compressive strength of rock and obtain more uniform radial strain.Compared with the specimens with the height of 50 mm and 60 mm，the uniaxial compressive strength of the specimens with the height of （25+50+25）mm and （20+60+20）mm is reduced by 38.41% and 39.69% respectively，ad-ditionally，the strength is also decreased comparing with the standard specimen.Numerical simulation results show that the uniaxial compressive strength of the combined specimen with or without end friction is close to the uniaxial compressive strength of the standard specimen in ideal state.All of the specimens have uniform radial strain without end friction.The radial strain of the combined specimen is relatively uniform when there is end effect.Numerical simulation results prove that the new experimental method reduces the end effect，but it can’t completely eliminate the end effect.
In order to explore the damage characteristics and crack evolution law of fractured rock mass under the combined influence of opening and cyclic loading and unloading of different stress levels，four kinds of single fractured rock materials with different opening （0.1，0.2，0.4，0.8 mm） were prepared by cement mortar，and three kinds of cyclic stress loading tests were carried out on rock-like materials based on RMT-150B rock mechanics testing machine.The characteristics of stress-strain curves，hysteretic loop area，dynamic elastic modulus and damage of fractured rock materials were analyzed.The test results show that the three kinds of stress cyclic loading roughly correspond to the three stages of pore compaction，elastic deformation and stable propagation of microcracks，and the peak strength of rock-like materials decreases with the increase of cyclic stress grade，the phenomenon of strength weakening occurs，and the hysteresis loop changes from “dense” to “sparse” at the beginning.Under the condition of the same stress level，with the increase of the number of cycles，the hysteresis loop area decreases sharply at first and then tends to be stable.In addition，there is an obvious difference in the decrease of the hysteresis loop area with different crack openings，the smaller the crack opening is，the smaller decrease of the hysteresis loop area is.Under the same number of cycles，the hysteresis loop area increases with the increase of crack opening and cyclic stress grade，and in the same cyclic stress grade and crack opening，the dynamic elastic modulus increases sharply at first and then tends to a stable value with the increase of the number of cycles.When the cyclic stress level and cyclic times are the same，the dynamic elastic modulus of rock-like materials decreases with the increase of crack opening.Under the same crack opening and cycle times，the dynamic elastic modulus increases at first and then decreases with the increase of cyclic stress grade，and with the increase of stress cycle grade and cycle times，the damage variable of rock-like materials shows the trend of decreasing first，then slow growth and then sharp increase，corresponding to the change law of the transition of hysteretic loop from “dense” to “sparse”.And the crack evolution of rock-like materials is different in different cyclic stress levels.
The interference vibration reduction technology based on precise delay hole by hole initiation is not only an effective means to reduce blasting vibration，but also can improve the effect of rock fragmentation and realize the active control of blasting vibration effect and harm.The key of this technology is to calculate the accurate and reasonable delay time under the conditions of reasonable hole layout parameters，single hole charge and charge structure conditions.However，due to the low time delay accuracy and instability of the conventional ordinary nonel detonator，the effect of controlling the millisecond delay interval to reduce the blasting vibration is not good.Engineering blasting operations are mostly carried out in complex environments and have strict requirements on blasting vibration.Combining previous research results，an accurate and reasonable delay time for underground shallow hole blasting was given.At the same time，combined with the field test research，the application of accurate delay time in reducing blasting vibration was explored.In view of the fact that the digital electronic detonator initiation network can realize the precise control of the delay time of precise delay hole by hole initiation，the delay time can be set flexibly and the performance is stable，using high-precision and high-strength digital electronic detonator，the field test of precise delay hole by hole initiation was designed and carried out.And the vibration waveform velocity of vibration time history signal was analyzed by using MA-TLAB 18.0. In the field test，vector synthesis of the waveform can be obtained，and the peak velocity of the vibration waveform under the delay time between holes of 25 ms is reduced by 27%，8%，29%，52% compared with the peak velocity of 15，20，30，35 ms successively.The peak value of the vibration waveform velocity under the delay time between rows of 75 ms is reduced by 28%，26% and 23% compared with the delay of 25 ms，125 ms and 200 ms between rows of single row blastholes.The test results show that the reasonable delay time between holes and rows can effectively reduce the blasting vibration intensity.
It is of great significance to investigate the penetration effect of high strength projectile on rock mass for the development of rock breaking technology in mine drilling.The penetration process is a process with large deformation of material.It is difficult for traditional finite element method to solve the problem with large deformation，which will lead to mesh distortion and calculation disruption.In order to obtain the damage responses of white granite under the condition of high speed penetration，the HJC material model was employed to model the white granite target and the projectile was assumed to be rigid.The HJC model was calibrated by the SHPB test data and the results show that the HJC model is capable to model the mechanical behavior of white granite under high strain rate conditions.The nonlinear finite element analysis software LS-DYNA was utilized and an SPH-FEM coupled method was developed to overcome the penetration problem with large deformation of granite target.A series of numerical simulation of projectile impacting white granite target with different velocity were carried out.The projectile is with diameter of 20 mm，CRH of 3 and length-diameter ratio of 6.The simulation results show that the SPH-FEM method can effectively simulate the mechanical damage response of rock target subjected to high speed impact.Based on the relationship between different impact velocities and penetration depth，an empirical formula for penetration depth of white granite is obtained，which can be used to predict the penetration depth of rock mass with similar strength.Finally，the effects of different nose shapes on penetration performance was studied. The results show that the penetration performance of flat-nose projectile is much lower than that of ogive-nose projectile，and the penetration damage area is smaller.The penetration depths of flat-nose projectile at initial velocity of 50，100，150，200，250 and 300 m/s are 16.7%，27.8%，35.1%，32.1%，36.1%，40.5% of the penetration depths of ogive-nose projectile，respectively.
With the construction of exploration and mining engineering and mining preparation engineering，the industrial orebody is gradually exposed.Compared with the exploration report，the shape of the orebody has changed greatly：（1）The thickness of the orebody becomes thinner and the grade is improved；（2）The stability of the orebody is poor，especially the soft and weak fault gouge exists in the hanging wall of most sections of the orebody.Based on the deterioration of ore occurrence conditions，if the open stope method recommended by the original preliminary design continues to be used，it will lead to low recovery rate，high dilution rate，poor safety and high safety production pressure.In order to adapt to the changed orebody occurrence conditions and solve the above-mentioned safety and economic problems existing in the preliminary design recommended open stope method，the open stope method is changed into a filling method with better safety，higher recovery rate and more environment-friendly.At the same time，reasonable stope structure parameters can effectively control the displacement of rock mass，improve the stress distribution of surrounding rock，and improve the stability of stope.In order to determine the optimal structural parameters of the stope in Gaoerqi lead zinc mine，five stope structure models were established according to the mine geological conditions and orebody occurrence state. The numerical simulation was carried out by the finite element software ANSYS.Comprehensive consideration of the tensile stress， compressive stress and displacement changes of the roof，inter-column，and filling body column，the safety factor is introduced to compare and analyze the simulation schemes.The results show that：Tensile stress occurs stress concentration at the boundary of the model；Compressive stress concentration occurs near the two ends of the stope；Displacement increases gradually with the increase of goaf span；The final optimized stope structure parameter is 75.0 m×6.0 m×1.8 m according to the factors of safety，economy and technology.However，due to the fact that the filling station has not been built，the goaf of one-step stoping can not be filled in time，the exposure time of roof is long，and the risk of roof collapse increases.It is proposed to adopt the one-step 3.5 m-wide strip tight mining method.Due to the increase of stope width in one step，the requirements for the strength of filling body have changed.The stope structure parameters to be adopted in the transition stage of the mine are：Room 75.0 m×3.5 m×1.8 m，pillar 75.0 m × 6.0 m×1.8 m.In order to determine the matching strength of filling body，the numerical simulation was carried out again，and the optimal strength range of filling body was determined to be 1.2~1.4 MPa.The practice in the transition stage of the mine shows that the scheme provides safe operation conditions and achieves good economic benefits，which has reference significance for similar mines.
Goaf is a major potential safety hazard of underground mines，and its stability has always been the focus attention of the majority of practitioners.Aiming at the difficulty in analysis and evaluation of the stability of quartz vein type wolframite ore veins and surrounding rocks，and there is no suitable method for analysis and evaluation of the stability of the goaf，the unascertained measurement theory was proposed.Firstly，11 factors affecting the stability of the goaf were selected，which including the mining width and the exposed area of roof，and the impact evaluates was conducted according to the stability classification of the goaf，thus， a single index measure function was constructed for the stability evaluation of quartz vein goaf.Then，the evaluation vector of multiple indexes comprehensive measurement was formed by determining the influence factor weight of each goaf.Finally，the stability evaluation level of each goaf is obtained based on the confidence recognition criterion.The results show that 55 are stable（Ⅰ） among the 191 goaf areas surveyed，82 are generally stable （Ⅱ），25 are less stable （Ⅲ），and 29 are unstable（Ⅳ）.The stability of the single-vein mining goaf of shallow hole retention method is generally better than that of the phase mining goaf，the less stable or unstable goaf is mainly vein zone.The recovery of the pillars greatly accelerates the instability of the goaf.The analysis also shows the mining width and the exposed area are the main factors controlling the stability of the goaf，and for this mining area，the stability limit of the mining width and the exposed area is 16 m and 800 m2 respectively.Based on the highly consistent of the evaluation results with the actual situation of the stability of the goaf，it is considered that the evaluation of the stability of the goaf based on the unascertained measurement theory provides a new way for the stability evaluation of the goaf of the quartz vein type tungsten mine.The two quantitative grading standards of mining width and roof exposed area proposed in this paper can be promoted and used in the analysis and evaluation of the stability of the goaf of the same type of mine.
Numerous of underground goaf left by metal mine mining not only bring a series of safety and environmental problems to the society，but also affect the development of mineral resources and the healthy and sustainable development of the national economy.The risk recognition of metal mine underground goaf is an important basis of its treatment，so accurately identify the danger of the goaf has become one of the problems to be solved urgently in the safety supervision of government departments and the safety production of mining enterprises.It has been difficult to accurately recognize metal mine underground goaf risk for many factors will influence the stability of underground goaf，and coexistence of quantitative and qualitative factors，and the existence of contradictions between these factors.In order to accurately identify the risk of metal mines underground goaf and manage the goaf economically and rationally，a risk recognition model of metal mine underground goaf based on relative difference function was established.First，a risk recognition index system of metal mine underground goaf containing 14 indexes was constructed according to the risk factors such as hydrogeological factors，goaf parameters，and other factors.Then the relative membership degree of the indexes to evaluation levels was calculated by relative difference function，and the combined weight of the indexes was determined by entropy weight method and analytical hierarchy process.Afterwards，the comprehensive relative membership degree and level characteristic value of metal mine underground goaf risk to different evaluation levels was calculated under four different combinations of distance parameter and optimization criteria parameter，and the level of metal mine underground goaf risk was then to be determined by the average level characteristic value.Furthermore，the whole process was applied to the risk recognition of eight underground goafs a tin mine and their calculated risk level was grade Ⅱ，grade Ⅱ，grade Ⅱ，grade Ⅰ，grade Ⅲ，grade Ⅰ，grade Ⅲ，grade Ⅰ，grade Ⅲ and grade Ⅰ，respectively.The calculation results fully consistent with the recognition results of uncertainty measurement and also well accordant with the practical situation，it also provides a helpful theoretical basis for the mine’s further treatment of underground goaf and safety production.The results show that the above established risk recognition model can self-verify the recognition results by changing its four combinations of its own parameters （distance parameter and optimization criteria parameter），which reflects the model’s overall control over the essential law of the unity and opposites of evaluation indexes.The model can improve the recognized reliability of underground goaf risk and its identification process is simple and efficient，which provides a new method for underground goaf risk recognition.
With the widely application of CAD and various mining softwares，new problems have arisen in mine production technology management and teamwork.Most mines now have accumulated data with TB magnitude and all kinds of data are not effectively digitized，which bring difficulties to information search and limite the flowing and sharing of data.In addition，with the continuous acceleration of mine informatization and intelligentization，many mining enterprises have gradually established various systems.Data between different systems is not fully and efficiently utilized.In the process of production management，data between each operation and technical link need to be submitted，sorted，summarized and approved manually，which result in low efficiency of technical cooperation.By analyzing the status of mine production technology，the concept of mining production technology collaboration was put forward.The key problems to be solved in mine production technology collaboration were clarified，and the system structure，main functions and construction value of mine production technology collaboration platform were expounded in detail.Mine production technology collabora-tion platform provides functions such as work flow，to-do list prompting，data submitting and updating，online previewing and approving.The platform have been successfully applied in an underground copper mine in Xinjiang，which contains 133 standardization of business data and 39 normalization of business processes.After the platform came into effect，business data was stored and accessed from data center.Business approval was transformed from manual to process-driven，and the data preparation time of technical personnel before processing business was greatly reduced.It made efficiently flowing and sharing of mine production technical data came true，and improved technical management and teamwork efficiency，and as a bridge to realize the seamless docking and deep integration between mining tool software，production execution system and 3D visualization control system.It can provide a reference for full life cycle business process collaboration，big data analysis and intelligent control system construction.
As a basic industry，mining needs innovative support in key links such as mining，dressing and metallurgy，so as to solve the problem of extensive and inefficient production，boost the construction of green mines and realize the high-quality development of mining.Research and development（R&D） funds are the premise and foundation for enterprises to carry out innovative R&D activities，and the quantity and quality of innovative achievements largely depend on the support of financing system and policy environment.Then，under the control of the “invisible hand” of the market，can the current financing channels of Chinese mining enterprises promote the R&D investment of enterprises？At the same time，under the intervention of the “visible hand” of the government，what role does the government subsidy obtained by mining enterprises play in the relationship between financing channels and R&D investment of enterprises？In this paper，starting from the sources of R&D investment，the listed mining companies in China from 2012 to 2019 were selected as samples，and the feasible generalized least squares method was used for empirical test.It is found that：（1）Both endogenous financing and exogenous financing can significantly promote R&D investment of Chinese mining enterprises.By further dividing the sources of external financing，it is found that equity financing can significantly promote R&D investment of mining enterprises，while debt financing has no significant impact. （2）Government subsidies have a significant positive regulatory effect on the relationship between endogenous financing and R&D investment of mining enterprises.（3）Government subsidies play a role of signal transmission in the relationship between external financing and R&D investment of mining enterprises，that is，government subsidies help mining enterprises to obtain more external financing，thus promoting the establishment of an intermediary role path for R&D investment of enterprises.To some extent，the conclusions of this paper provide reference value for R&D financing of mining enterprises in China，and provide microscopic evidence for the government to formulate relevant subsidy policies，and promote independent innovation of enterprises and the development of capital market.
Refractory gold ores resources is widely distributed in the Gansu Province，Qinghai Province and Guizhou Province of China.There is usually a high gold content in these refractory gold ores，but the refractory gold ore contains generally a certain amount of Sb-bearing，As-bearing and C-bearing minerals，which is the important factor effecting the recovery of gold from the refractory gold ores.In recent years，more attention was paid to how to improve the recovery of gold from the refractory.During the development and utilization of the refractory gold ore，the research of mineralogy plays an important role in investigating the occurrence state of gold in ores and the factor effecting the recovery of gold. In addition，mineralogy is still a key parameter to determine the reasonable processing technology. In this paper，the mineralogy of a refractory gold ore from Qinghai Province of China was investigated，which contains Au 5.2×10-6，S 1.82%，As 1.01%，Sb 0.73% and Fe 4.19% respectively. The recovery of gold by the cyanide leaching is less than 50% in laboratory scale.To find the reason for the low recovery of gold by cyanide leaching and the occurrence state of gold and Au-bearing in ores，the processing mineralogy of the refractory ore was investigated by a method combining the X-ray diffraction（XRD） and scanning electron microscope（SEM-EDS） with the optical microscope.Results from the processing mineralogy indicat that there are three occurrence state of gold in this refractory ore，there are the natural gold，the gold enclosed in sulfide minerals and the gold enclosed in gangue minerals.The natural gold with the percentage of 42.87% in total gold is mainly distributed in the interface between stibnite，arsenopyrite and quartz，and the natural gold is easily recovered due to the coarse dissemination particle size.The gold enclosed in sulfide minerals is 46.83% with Au content of 2.43×10-6.In this refractory gold ore，most of gold was enclosed in sulfide minerals such as stibnite，arsenopyrite and pyrite in the formation of microscopic or submicroscopic gold，which is difficult to recovery by cyanide leaching due to the fine dissemination particle size.The gold enclosed in sulfide mineral cannot contact with the leaching reagents，which is the primary reason for the low recovery of gold with the cyanide leaching.In addition，a part of gold in ores with the percentage of 10.3% is distributed in gangue minerals such as quartz，feldspar and calcite in the formation of micro-inclusion.Basis on the study of the occurrence state of gold and the characteristics of the intercalation relationship of the main gold-bearing minerals，the main mineralogical factors affecting the recovery of gold in the ore were discussed.In view of the low proportion of natural gold in the refractory gold ore and the high content of gold encapsulated in sulfide minerals，the reasonable beneficiation process of “rough grinding-centrifugal gravity separation-fine grinding-flotation-floating tail cyanide leaching” was proposed to strengthen the recovery of coarse-grained natural gold and sulfide mineral-coated gold in the ore.Laboratory studies have shown that this process can achieve high-efficiency recovery of gold in the refractory gold mine.The results provide an important reference with the comprehensive utilization of the refractory gold ores.
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