The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of co...The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of conveyor system are studied, and their calculating models are built up.展开更多
Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using I...Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis （INAA）, Inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）, Cold-Vapor Atomic Absorption Spectrometry （CV-AAS） and Graphite Furnace Atomic Absorption Spectrometry （GF-AAS）. Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that： （a） the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; （b） the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; （c） the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; （d） the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that： （a） pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; （b） Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; （c） U, Zn, V, Na, P maybe controlled by phosphate or halite; （d） Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor.展开更多
Modem surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference be...Modem surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference between sub-systems and the lag in management skills has been a bottle neck for improving productivity of the system. Based on the fact that the traditional tools for safety analysis have been insufficient to evaluate systematically and dynamically the safety risks, this paper tries to create a virtual reality tool consisting of human, machine and mines, using Pro/E and the 3D MAX software in order to evaluate visually the operations of typical mining equipment, such as the bucket wheel excavator （BWE）, the shovel, the truck and the dragline. Within this virtual world, the behavior of the system, such as interaction, interference and potential risk can be replayed and reviewed visually. The objective of the study is to identify the critical safety issues of the system and to provide a convenient and powerful tool for safety training and safety management.展开更多
The three-dimensional （3D） deformation effect of the slope engineering under the step-by-step excavation for the Antaibao surface mine was analyzed using the FLAC^3D technique. An optimal excavated scheme with a rel...The three-dimensional （3D） deformation effect of the slope engineering under the step-by-step excavation for the Antaibao surface mine was analyzed using the FLAC^3D technique. An optimal excavated scheme with a relatively steeper slope angle of 47° instead of 30° was successfully implemented at the west wall in the geological section 73200 of the mine area, where the 3D effect of the nonlinear large deformation of the slope was taken into account. Based on the above research conclusion, put forward the countermeasures of shortening mining length, excavating by different regions, timely foot backfilling to protect the excavated slope, and monitoring and feedback adjustment by studying the nonlinear effect. The results show that these countermeasures are effective in controlling maximum deformation and increasing the stability of the slope.展开更多
A semi-continuous technology combines the merits of discontinuous and continuous technologies. Compared with the discontinuous technology, the semi-continuous technology can be used to decrease haulage costs in mines ...A semi-continuous technology combines the merits of discontinuous and continuous technologies. Compared with the discontinuous technology, the semi-continuous technology can be used to decrease haulage costs in mines be- cause of the use of a belt conveyor instead of trucks. The method may improve efficiency by using shovels instead of BWE. This paper discusses the removal distance of a crushing station based on the Buzhaoba surface mine.展开更多
The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chass...The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue failures.These events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic impact.This work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of machine.For this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's model.The model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics.展开更多
Yima Coal Corporation is considering to adopt highwall mining method withauger machine to recover coal from north surface pit that has reached final highwall position. Themajor geomechanical issues associated with aug...Yima Coal Corporation is considering to adopt highwall mining method withauger machine to recover coal from north surface pit that has reached final highwall position. Themajor geomechanical issues associated with auger mining are highwall and pillar stability. Based onthe field investigation and laboratory test results of mechanical parameters, numerical modeling iscarried out to assess the stability of highwall and pillar. Field measurements of highwalldeformation have been used to validate and ensure the confidence for the development of realisticmodels. The results of numerical modeling show that the mining method is feasible for mining theseam of 10 m thickness in north surface coal mine.展开更多
Surface miner, a continuous mining machine, is being manufactured in India and abroad owing to enhanced demand of production in various mining industries like coal, limestone, gypsum, bauxite etc. Different types of s...Surface miner, a continuous mining machine, is being manufactured in India and abroad owing to enhanced demand of production in various mining industries like coal, limestone, gypsum, bauxite etc. Different types of surface miners are manufactured today based on cutting drum placement and design specifications. Selective mining without drilling and blasting, high production and small size products are some of the prominent attractive features obtained with these moving marvels. This machine can be used with good efficiency in soft to medium hard rock (100-120 MPa). This paper synthesizes the different applications, equipment models, features offered, operating methods, cutting performance assessment models as well as typical production performance of surface miner in coal and limestone mines of India. Engine hour metre reading, diesel and pick consumptions are linearly influenced by production. The emphasis for future research is also brought out.展开更多
The development and experiment of a computer-controlled truck dispatching system in Surface mine is presented in this paper.It includes the system overall design, the system working mode design, the selection of the b...The development and experiment of a computer-controlled truck dispatching system in Surface mine is presented in this paper.It includes the system overall design, the system working mode design, the selection of the best truck travel path, the development of truck fleet programming, the development of database management system, and the development of truck real time dispatching, etc. The successful experiment is carried out in Huolinhe surface mine, and the satisfied results are obtained. Application of this system can improve the system production and the mine management. This system is the first one in our country at present.展开更多
It is stipulated in the China national document, named'The Economical Appraisal Methods for Construction Projects' that dynamic analysis should dominate the project economical appraisal methods. This paper has...It is stipulated in the China national document, named'The Economical Appraisal Methods for Construction Projects' that dynamic analysis should dominate the project economical appraisal methods. This paper has set up a dynamic investment forecast model for Yuanbaoshan Surface Coal Mine. Based on this model, the investment reliability using simulation and analytic methods has been analysed, and the probability that the designed internal rate of return can reach 8.4%, from economic points of view, have been also studied.展开更多
In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for th...In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for the remote dispatcher, a 3D assisted driving system (3D-ADS) based on the GPS, mesh-wireless networks and the Google-Earth engine as the graphic interface and mine-mapping server, was developed at Virginia Tech. The research results indicate that this 3D-ADS system has the potential to increase reliability and reduce uncertainty in open pit mining operations by customizing the local 3D digital mining map, con-structing 3D truck models, tracking vehicles in real time using a 3D interface and indicating available escape routes for driver safety.展开更多
The paper aims to identify a reasonable method for mining ultra-thick coal seams in an end-slope in surface mine, With a case study of Heidaigou surface coal mine(HSCM), the paper conducted a comparative research on t...The paper aims to identify a reasonable method for mining ultra-thick coal seams in an end-slope in surface mine, With a case study of Heidaigou surface coal mine(HSCM), the paper conducted a comparative research on three mining methods, namely Underground Mining Method(UMM), Highwall Mining System(HMS) and Local Steep Slope Mining Method(LSSMM). A model was firstly established to simulate the impact that UMM and HMS exert on monitoring points and surface deformation. The way that stripping and excavation amount varies with different slope angle, and the corresponding end slope stability were analyzed in the mode of LSSMM. Then a TOPSIS model was established by taking into account six indicators such as recovery ratio, technical complexity and adaptability, the impact on surface mining production, production safety and economic benefits. Finally, LSSMM was determined as the best mining method for mining ultra-thick coal seams in end slope in HSCM.展开更多
This paper describes a new technique for the roadway dust control in surface mine. In the method, the emulsified tar liquid with low concentration and the super water-absorbing resin are taken as dust adhesive and spr...This paper describes a new technique for the roadway dust control in surface mine. In the method, the emulsified tar liquid with low concentration and the super water-absorbing resin are taken as dust adhesive and sprayed on the roadway. After doing a large number of in-situ experiments, the technique has shown its excellent characteristics on sticking dust, preventing water evaporation and reducing the combined cost of truck transportation.展开更多
Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The main purpose of this study is to develop a drill selec- t...Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The main purpose of this study is to develop a drill selec- tion methodology and simultaneously a performance evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accomplished by 5 different drill machines of Ingersoll-Rand and Revathi working in coal mines of Sonepur Bazari （SECL） and Block-II （BCCL）. The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ramler Diagram, coarseness index （CI）, mean chip size （d）, specific-st trace area （SSA） and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through multiple regressions was found to have a very good correlation with an index of determination of 0.85. A comparative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index （DEUI）, for mapping of drill machine to bench, The developed DEU1 can aid in selecting or mapping a right machine to right bench for achieving higher penetration rate and utilizations.展开更多
The connection between all the single systems iu combined technology is analysed, and the mine engineering reliability is calculated in any area of the mines using combined technololgy system. The reliability design a...The connection between all the single systems iu combined technology is analysed, and the mine engineering reliability is calculated in any area of the mines using combined technololgy system. The reliability design and distribution method in this system is put forward, thus the basis is set for the decision to raise the total production capability or the surface mines in which the combined system is used.展开更多
A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of ...A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of the United States, this paper deeply studies the reclamation technique of surface mining by a CPS and comprehensively evaluates its reclamation effect. Problerns and improvements of the reclamation technique are also discussed in this paper.展开更多
This paper introduced an approach to surface mine planning optimization-Goal Programming.The multiobjective[0-1] model has been built and the software has been developed.The method has been applied to a huge surface c...This paper introduced an approach to surface mine planning optimization-Goal Programming.The multiobjective[0-1] model has been built and the software has been developed.The method has been applied to a huge surface coal mine,the result of which shows that it is effective and feasible.展开更多
We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by&quo...We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error.展开更多
The luminescence behavior of Eu^(3+)-activated lanthanum tungstate nanophosphors exhibiting intense red emission was systematically explored by modifying their surfaces using various agents,including polyvinylpyrrolid...The luminescence behavior of Eu^(3+)-activated lanthanum tungstate nanophosphors exhibiting intense red emission was systematically explored by modifying their surfaces using various agents,including polyvinylpyrrolidone(PVP),cetyltrimethylammonium bromide(CTAB),trisodium citrate(TC),polyvinyl alcohol(PVA),and ethylene glycol(EG).These nanophosphors were synthesized via a facile hydrothermal-assisted solid-state reaction.X-ray diffraction(XRD)analysis confirmed the orthorhombic crystal structure of all the prepared samples.Morphological and size analyses were performed using scanning electron microscopy(SEM)and particle size distribution profiling.High-resolution transmission electron microscopy(HRTEM)complemented by elemental mapping was used to evaluate the particle dimensions and interplanar spacing of the optimized sample.Fourier-transform infrared spectroscopy(FTIR)was used to identify functional groups and assign corresponding vibrational bands.X-ray photoelectron spectroscopy(XPS)provided insights into the elemental composition and binding energies of the optimized nanophosphors.Notably,the PVA-modified sample doped with 14mol%Eu3+exhibited pronounced red emission at 616 nm,attributed to the ^(5)D_(0)→^(7)F_(2) electric dipole transition of Eu3+ions under ultraviolet(UV)excitation.Detailed excitation and emission spectral analyses were performed,with band assignments corresponding to the relevant electronic transitions.Among the surface-treated variants,the PVA-modified nanophosphors demonstrated exceptional color purity of 99.6%,international commission on illumination(CIE)chromaticity coordinates of(0.6351,0.3644),and a correlated color temperature of 1147 K.These superior optical features are ascribed to the enhanced surface passivation and suppression of nonradiative recombination,facilitated effectively by the PVA surface layer.Lifetime decay analysis across all samples revealed a significantly extended lifetime for the optimized composition,further supporting its superior luminescence efficiency.In addition,evaluation of the biocompatibility of the nano-phosphors highlighted their potential for biomedical applications.Overall,these findings emphasize the efficacy of PVA-modified Eu^(3+)-doped lanthanum tungstate nanophosphors as highly efficient red emitters,suitable for application in white light-emitting diodes(WLEDs)and latent fingerprint detection while offering valuable insights into the role of surface modification in tuning the optical properties of nanophosphors.展开更多
In this study,an amine-reactive poly(pentafluorophenyl acrylate)(PPFPA)platform was developed for advanced surface engineering of next-generation sequencing(NGS)chips.Through post-polymerization modification,PPFPA was...In this study,an amine-reactive poly(pentafluorophenyl acrylate)(PPFPA)platform was developed for advanced surface engineering of next-generation sequencing(NGS)chips.Through post-polymerization modification,PPFPA was functionalized with dual moieties:azide groups for covalent immobilization of DBCO-modified DNA primers via click chemistry and tunable hydrophilic side chains to optimize biocompatibility and surface properties.Systematic screening revealed that hydrophobic azide carriers combined with neutral hydroxyl groups maximized the DNA immobilization efficacy,approaching the performance of commercial polyacrylamide-based polymers.The negatively charged carboxyl groups severely impede DNA primer attachment.Higher molecular weight derivatives further enhance the efficacy of DNA immobilization.In NGS validation,optimized surface modification polymers achieved robust surface density of clustered DNA and high sequencing accuracy,surpassing quality benchmarks and comparable to those of conventional analogs.This platform demonstrates significant potential for tailoring high-sensitivity surfaces for genomic applications,advancing clinical diagnostics,and personalized medicine.展开更多
文摘The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of conveyor system are studied, and their calculating models are built up.
基金This research was supported by the National Natural Science Foundation of China （No. 90010017 and No. 40272071）the National Major Fundamental Research and Development Project （2006 CB200304）.
文摘Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis （INAA）, Inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）, Cold-Vapor Atomic Absorption Spectrometry （CV-AAS） and Graphite Furnace Atomic Absorption Spectrometry （GF-AAS）. Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that： （a） the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; （b） the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; （c） the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; （d） the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that： （a） pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; （b） Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; （c） U, Zn, V, Na, P maybe controlled by phosphate or halite; （d） Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor.
基金Project 2002CB412705 supported by the Major State Basic Research Development Program (973) of China
文摘Modem surface mines, either mono-system or multi-systems, need a large fleet of equipment consisting of excavators, loaders, haulers and auxiliary machines. Presently, the complexity of the system, the interference between sub-systems and the lag in management skills has been a bottle neck for improving productivity of the system. Based on the fact that the traditional tools for safety analysis have been insufficient to evaluate systematically and dynamically the safety risks, this paper tries to create a virtual reality tool consisting of human, machine and mines, using Pro/E and the 3D MAX software in order to evaluate visually the operations of typical mining equipment, such as the bucket wheel excavator （BWE）, the shovel, the truck and the dragline. Within this virtual world, the behavior of the system, such as interaction, interference and potential risk can be replayed and reviewed visually. The objective of the study is to identify the critical safety issues of the system and to provide a convenient and powerful tool for safety training and safety management.
基金Supported by the National Natural Science Foundation of China(10572008)the Natural Science Foundation of Beijing(3063019)Doctor Foundation of Yanshan University(B245)
文摘The three-dimensional （3D） deformation effect of the slope engineering under the step-by-step excavation for the Antaibao surface mine was analyzed using the FLAC^3D technique. An optimal excavated scheme with a relatively steeper slope angle of 47° instead of 30° was successfully implemented at the west wall in the geological section 73200 of the mine area, where the 3D effect of the nonlinear large deformation of the slope was taken into account. Based on the above research conclusion, put forward the countermeasures of shortening mining length, excavating by different regions, timely foot backfilling to protect the excavated slope, and monitoring and feedback adjustment by studying the nonlinear effect. The results show that these countermeasures are effective in controlling maximum deformation and increasing the stability of the slope.
文摘A semi-continuous technology combines the merits of discontinuous and continuous technologies. Compared with the discontinuous technology, the semi-continuous technology can be used to decrease haulage costs in mines be- cause of the use of a belt conveyor instead of trucks. The method may improve efficiency by using shovels instead of BWE. This paper discusses the removal distance of a crushing station based on the Buzhaoba surface mine.
文摘The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue failures.These events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic impact.This work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of machine.For this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's model.The model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics.
文摘Yima Coal Corporation is considering to adopt highwall mining method withauger machine to recover coal from north surface pit that has reached final highwall position. Themajor geomechanical issues associated with auger mining are highwall and pillar stability. Based onthe field investigation and laboratory test results of mechanical parameters, numerical modeling iscarried out to assess the stability of highwall and pillar. Field measurements of highwalldeformation have been used to validate and ensure the confidence for the development of realisticmodels. The results of numerical modeling show that the mining method is feasible for mining theseam of 10 m thickness in north surface coal mine.
文摘Surface miner, a continuous mining machine, is being manufactured in India and abroad owing to enhanced demand of production in various mining industries like coal, limestone, gypsum, bauxite etc. Different types of surface miners are manufactured today based on cutting drum placement and design specifications. Selective mining without drilling and blasting, high production and small size products are some of the prominent attractive features obtained with these moving marvels. This machine can be used with good efficiency in soft to medium hard rock (100-120 MPa). This paper synthesizes the different applications, equipment models, features offered, operating methods, cutting performance assessment models as well as typical production performance of surface miner in coal and limestone mines of India. Engine hour metre reading, diesel and pick consumptions are linearly influenced by production. The emphasis for future research is also brought out.
文摘The development and experiment of a computer-controlled truck dispatching system in Surface mine is presented in this paper.It includes the system overall design, the system working mode design, the selection of the best truck travel path, the development of truck fleet programming, the development of database management system, and the development of truck real time dispatching, etc. The successful experiment is carried out in Huolinhe surface mine, and the satisfied results are obtained. Application of this system can improve the system production and the mine management. This system is the first one in our country at present.
基金This project has been supported by the seience foundation of the doctorate programmes of the National Education Commission.
文摘It is stipulated in the China national document, named'The Economical Appraisal Methods for Construction Projects' that dynamic analysis should dominate the project economical appraisal methods. This paper has set up a dynamic investment forecast model for Yuanbaoshan Surface Coal Mine. Based on this model, the investment reliability using simulation and analytic methods has been analysed, and the probability that the designed internal rate of return can reach 8.4%, from economic points of view, have been also studied.
基金Financial support for this work, provided by the Key Programs of the National Science and Technology Foundation during the 11th Five-Year Plan Period (No.2006BAK04B04) the State Scholarship Fund (No.2007104096), is gratefully acknowledged
文摘In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for the remote dispatcher, a 3D assisted driving system (3D-ADS) based on the GPS, mesh-wireless networks and the Google-Earth engine as the graphic interface and mine-mapping server, was developed at Virginia Tech. The research results indicate that this 3D-ADS system has the potential to increase reliability and reduce uncertainty in open pit mining operations by customizing the local 3D digital mining map, con-structing 3D truck models, tracking vehicles in real time using a 3D interface and indicating available escape routes for driver safety.
基金provided by the National Natural Science Foundation of China(No.90510002)the Science and Technology Research of the Ministry of Education of China(No.306008)
文摘The paper aims to identify a reasonable method for mining ultra-thick coal seams in an end-slope in surface mine, With a case study of Heidaigou surface coal mine(HSCM), the paper conducted a comparative research on three mining methods, namely Underground Mining Method(UMM), Highwall Mining System(HMS) and Local Steep Slope Mining Method(LSSMM). A model was firstly established to simulate the impact that UMM and HMS exert on monitoring points and surface deformation. The way that stripping and excavation amount varies with different slope angle, and the corresponding end slope stability were analyzed in the mode of LSSMM. Then a TOPSIS model was established by taking into account six indicators such as recovery ratio, technical complexity and adaptability, the impact on surface mining production, production safety and economic benefits. Finally, LSSMM was determined as the best mining method for mining ultra-thick coal seams in end slope in HSCM.
文摘This paper describes a new technique for the roadway dust control in surface mine. In the method, the emulsified tar liquid with low concentration and the super water-absorbing resin are taken as dust adhesive and sprayed on the roadway. After doing a large number of in-situ experiments, the technique has shown its excellent characteristics on sticking dust, preventing water evaporation and reducing the combined cost of truck transportation.
文摘Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The main purpose of this study is to develop a drill selec- tion methodology and simultaneously a performance evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accomplished by 5 different drill machines of Ingersoll-Rand and Revathi working in coal mines of Sonepur Bazari （SECL） and Block-II （BCCL）. The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ramler Diagram, coarseness index （CI）, mean chip size （d）, specific-st trace area （SSA） and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through multiple regressions was found to have a very good correlation with an index of determination of 0.85. A comparative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index （DEUI）, for mapping of drill machine to bench, The developed DEU1 can aid in selecting or mapping a right machine to right bench for achieving higher penetration rate and utilizations.
文摘The connection between all the single systems iu combined technology is analysed, and the mine engineering reliability is calculated in any area of the mines using combined technololgy system. The reliability design and distribution method in this system is put forward, thus the basis is set for the decision to raise the total production capability or the surface mines in which the combined system is used.
文摘A cross-pit system (CPS) could combine the excavation of coal and the reclamation of land together, thus it has been widely used in many countries. Based on a field experiment at Horse Creek mine in Illinois State of the United States, this paper deeply studies the reclamation technique of surface mining by a CPS and comprehensively evaluates its reclamation effect. Problerns and improvements of the reclamation technique are also discussed in this paper.
文摘This paper introduced an approach to surface mine planning optimization-Goal Programming.The multiobjective[0-1] model has been built and the software has been developed.The method has been applied to a huge surface coal mine,the result of which shows that it is effective and feasible.
文摘We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error.
基金financial support provided by the National Research Foundation of Korea(NRF)through the Basic Science Research Program,funded by the Ministry of Education(Nos.2021R1A6A1A03039493 and 2022R1A2C1009389)the authors extend their appreciation to the Researchers Supporting Project(No.RSPD2025R956)。
文摘The luminescence behavior of Eu^(3+)-activated lanthanum tungstate nanophosphors exhibiting intense red emission was systematically explored by modifying their surfaces using various agents,including polyvinylpyrrolidone(PVP),cetyltrimethylammonium bromide(CTAB),trisodium citrate(TC),polyvinyl alcohol(PVA),and ethylene glycol(EG).These nanophosphors were synthesized via a facile hydrothermal-assisted solid-state reaction.X-ray diffraction(XRD)analysis confirmed the orthorhombic crystal structure of all the prepared samples.Morphological and size analyses were performed using scanning electron microscopy(SEM)and particle size distribution profiling.High-resolution transmission electron microscopy(HRTEM)complemented by elemental mapping was used to evaluate the particle dimensions and interplanar spacing of the optimized sample.Fourier-transform infrared spectroscopy(FTIR)was used to identify functional groups and assign corresponding vibrational bands.X-ray photoelectron spectroscopy(XPS)provided insights into the elemental composition and binding energies of the optimized nanophosphors.Notably,the PVA-modified sample doped with 14mol%Eu3+exhibited pronounced red emission at 616 nm,attributed to the ^(5)D_(0)→^(7)F_(2) electric dipole transition of Eu3+ions under ultraviolet(UV)excitation.Detailed excitation and emission spectral analyses were performed,with band assignments corresponding to the relevant electronic transitions.Among the surface-treated variants,the PVA-modified nanophosphors demonstrated exceptional color purity of 99.6%,international commission on illumination(CIE)chromaticity coordinates of(0.6351,0.3644),and a correlated color temperature of 1147 K.These superior optical features are ascribed to the enhanced surface passivation and suppression of nonradiative recombination,facilitated effectively by the PVA surface layer.Lifetime decay analysis across all samples revealed a significantly extended lifetime for the optimized composition,further supporting its superior luminescence efficiency.In addition,evaluation of the biocompatibility of the nano-phosphors highlighted their potential for biomedical applications.Overall,these findings emphasize the efficacy of PVA-modified Eu^(3+)-doped lanthanum tungstate nanophosphors as highly efficient red emitters,suitable for application in white light-emitting diodes(WLEDs)and latent fingerprint detection while offering valuable insights into the role of surface modification in tuning the optical properties of nanophosphors.
基金financially supported by the Science and Technology Commission of Shanghai Municipality(No.24ZR1401400)Shenzhen Salus Bio Med Company for their strong support in this study。
文摘In this study,an amine-reactive poly(pentafluorophenyl acrylate)(PPFPA)platform was developed for advanced surface engineering of next-generation sequencing(NGS)chips.Through post-polymerization modification,PPFPA was functionalized with dual moieties:azide groups for covalent immobilization of DBCO-modified DNA primers via click chemistry and tunable hydrophilic side chains to optimize biocompatibility and surface properties.Systematic screening revealed that hydrophobic azide carriers combined with neutral hydroxyl groups maximized the DNA immobilization efficacy,approaching the performance of commercial polyacrylamide-based polymers.The negatively charged carboxyl groups severely impede DNA primer attachment.Higher molecular weight derivatives further enhance the efficacy of DNA immobilization.In NGS validation,optimized surface modification polymers achieved robust surface density of clustered DNA and high sequencing accuracy,surpassing quality benchmarks and comparable to those of conventional analogs.This platform demonstrates significant potential for tailoring high-sensitivity surfaces for genomic applications,advancing clinical diagnostics,and personalized medicine.
