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Rockburst management in Canadian hard rock mines

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1036-1043页

作者： B.P.Simser glencore’s Sudbury Integrated Nickel Operations

Rockburst is a complex mining-induced phenomenon that remains difficult to be *** particular,geological conditions contributing to rockbursts are more variable than those in many conventional engineering ***,intact rock properties,and other rock mass conditions vary,sometimes,within small *** levels that store energy or drive structures can change with geological *** example,faults may channel stress between the void and the discontinuity,and/or alter the local stress ***-strength rock masses may be very massive at shallow depth,allowing for large/stable *** same rock type may store excessive strain energy at depth or high mineral extraction,and lead to *** robust ground support systems that can bear dynamic loading are now commonplace in mining industry.A typical approach would be able to evaluate rockburst potential,and selectively deploy more robust ground support *** resistant support is more expensive in installation than most support systems designed for gravity ***,an excessively conservative risk assessment can affect both direct support costs and *** mines continue to go deeper,selective use of burst-prone support may not be an optimal choice,and pervasive installation may become *** implies a need to maintain a reasonable installation speed,and the time to get to deep orebodies is a major economic *** paper shows field examples of rockbursts to highlight some of the complex issues related to the rockburst.A multi-tiered risk mitigation approach is used for rockburst *** of risk reduction strategies are given and some examples from a deep hard rock mine are used to illustrate the relative success of the *** that some residual risks to worker safety remain,discussion is presented on where more research or process improvements would be beneficial.

关键词： Rockburst Dynamic support Seismic monitoring

An investigation of machine learning techniques to estimate minimum horizontal stress magnitude from borehole breakout

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International Journal of Mining Science and Technology 2022年第5期32卷 1021-1029页

作者： Huasheng Lin Sarvesh Kumar Singh Zizhuo Xiang Won Hee Kang Simit Raval Joung Oh Ismet Canbulat glencore Coal Assets Australia Mount Thorley 2330Australia School of Minerals and Energy Resources Engineering University of New South WalesSydney 2052Australia Centre for Infrastructure Engineering School of EngineeringWestern Sydney UniversityPenrith 2751Australia

Borehole breakout is a widely utilised phenomenon in horizontal stress orientation determination,and breakout geometrical parameters,such as width and depth,have been used to estimate both horizontal stress ***,the accuracy of minimum horizontal stress estimation from borehole breakout remains relatively low in comparison to maximum horizontal stress *** paper aims to compare and improve the minimum horizontal stress estimation via a number of machine learning(ML)regression techniques,including parametric and non-parametric models,which have rarely been *** models were trained based on 79 laboratory data from published literature and validated against 23 field data.A systematic bias was observed in the prediction for the validation dataset whenever the horizontal stress value exceeded the maximum value in the training ***,the pattern was captured,and the removal of systematic bias showed that the artificial neural network is capable of predicting the minimum horizontal stress with an average error rate of 10.16%and a root mean square error of 3.87 MPa when compared to actual values obtained through conventional in-situ measurement *** is a meaningful improvement considering the importance of in-situ stress knowledge for underground operations and the availability of borehole breakout data.

关键词： Borehole breakout In-situ stress estimation Comparative analysis Machine learning

Management of floor heave at Bulga Underground Operations – A case study

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International Journal of Mining Science and Technology 2019年第1期29卷 73-78页

作者： Sungsoon Mo Kudret Tutuk Serkan Saydam School of Minerals and Energy Resources Engineering The University of New South Wales glencore Coal Assets Australia

This paper presents an overview of the floor heave management at the glencore Bulga Underground Operations and investigates the contributing factors to the behaviour of the floor. The mine experienced a number of major floor heave events in gateroads on development. As the longwall face approached the roadways, the magnitude of floor heave frequently increased, while new floor heave also ***, severe floor heave events took place along the longwall face. The most observed failure mode was buckling. While regular floor measurements were conducted to better understand the nature of the phenomenon, and various measures were considered to control the deformation of floor, the mining height was increased for the predicted floor heave domains, which facilitated effective management of the floor issues. The experience in the mine indicates that mainly high horizontal stresses with greater depths of cover and certain types of floor lithology configuration are likely to contribute to the failures of floor strata.

关键词： Floor heave Floor failure Buckling Failure mechanism

Experimental and numerical studies on progressive debonding of grouted rock bolts

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International Journal of Mining Science and Technology 2022年第1期32卷 63-74页

作者： Hao Shi Lei Song Houquan Zhang Wenlong Chen Huasheng Lin Danqi Li Guozhu Wang Huayun Zhao State Key Laboratory for Geomechanics&Deep Underground Engineering School of Mechanics&Civil EngineeringChina University of Mining and TechnologyXuzhou 221116China School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China School of Water Energy and EnvironmentCranfield UniversityCranfield MK430ALUK glencore Coal Assets Australia Mount ThorleyNSW 2330Australia WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityKalgoorlie WA6430Australia

Understanding the mechanism of progressive debonding of bolts is of great significance for underground *** this paper,both laboratory experiment and numerical simulation of the pull-out tests were *** experimental pull-out test specimens were prepared using cement mortar material,and a relationship between the pull-out strength of the bolt and the uniaxial compressive strength(UCS)of cement mortar material specimen was *** locations of crack developed in the pull-out process were identified using the acoustic emission(AE)*** pull-out test was reproduced using 2D Particle Flow Code(PFC^(2D))with calibrated *** experimental results show that the axial displacement of the cement mortar material at the peak load during the test was approximately 5 mm for cement-based grout of all *** contrast,the peak load of the bolt increased with the UCS of the confining *** peak load,cracks propagated to less than one half of the anchorage length,indicating a lag between crack propagation and axial bolt load *** simulation results show that the dilatation between the bolt and the rock induced cracks and extended the force field along the anchorage direction;and,it was identified as the major contributing factor for the pull-out failure of rock bolt.

关键词： Bolt pull-out test Bolt failure process AE positioning Meso-interaction PFC2D simulation

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X射线光电子能谱仪的结合能会测报告

真空科学与技术学报 1984年第2期 101-104+114页

作者： xps Round Robin Group written by Wang Xun,Yu Minren,Fudan University,Shanghai,CHINA xps会测组

用镍、铜、银、金四种样品对不同型号的11台X射线光电子能谱仪作了结合能会测。虽然不同仪器对同一个峰测得的结合能可以相差leV以上,但其平均值与已经发表的精确数据符合得比较好。提出了用Ni3d价带边及四种金属的各峰位来校正谱仪结... 详细信息

用镍、铜、银、金四种样品对不同型号的11台X射线光电子能谱仪作了结合能会测。虽然不同仪器对同一个峰测得的结合能可以相差leV以上,但其平均值与已经发表的精确数据符合得比较好。提出了用Ni3d价带边及四种金属的各峰位来校正谱仪结合能读数的建议。样品表面自然沾污C1s;结合能的测量值有较大的离散性,一般情况下最好不用它作为结合能的内标。

关键词：结合能束缚能光电子能谱仪仪器

Co-promoted Mo-carbide catalytic system for sustainable manufacturing of chemicals via co-processing of CO_(2) with ethane

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Green Carbon 2023年第1期1卷 94-103页

作者： Vera Bikbaeva Nikolay Nesterenko Nuria García-Moncada Valentin Valtchev Laboratoire Catalyse et Spectrochimie ENSICAENUniversitéde CaenCNRS6 Boulevard Maréchal Juin14050 CaenFrance Servicios Generales de Investigación XPSCentro de InvestigaciónTecnología e Innovación de la Universidad de Sevilla(CITIUS)Av.Reina Mercedes 4B41012SevillaSpain

The study reports progress in developing a molybdenum carbide-based catalyst for co-processing ethane and CO_(2).The cobalt promoting of molybdenum carbide improved the activity and stability of ethane transformation in the presence of CO_(2) substantially without any impact on ethylene *** Mo-Co supported catalyst also showed interesting performance in catalyzing ethane dry reforming and that application could be a perspective further use for this *** addition,the comprehensive analysis of mono-and bi-metallic catalysts revealed that Co-promoting prevented rapid Mo-carbide ***,tuning operation conditions allowed to control catalyst’s selectivity and maximize CO_(2) utilization or ethylene formation.

关键词： CO_(2)utilization Oxidative dehydrogenation CO_(2)negative ethylene production Cobalt-molybdenum synergy Embryonic zeolite

Discussions on rockburst and dynamic ground support in deep mines

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1110-1118页

作者： Charlie C.Li Peter Mikula Brad Simser Bruce Hebblewhite William Joughin Xiaowei Feng Nuwen Xu Norwegian University of Science and Technology (NTNU) Trondheim Norway Mikula Geotechnics Pty. Ltd. Kalgoorlie Australia glencore Company Sudbury Canada The University of New South Wales (UNSW) Sydney Australia SRK Consulting Johannesburg South Africa China University of Mining and Technology Xuzhou China Sichuan University Chengdu China

The paper is a summary of discussions on four topics in rockburst and dynamic ground *** 1 is the mechanisms of *** events are classified into two categories in accordance with the triggering mechanisms,*** burst and fault-slip *** burst occurs on rock surfaces when the tangential stress exceeds the rock strength in hard and brittle ***-slip burst is triggered by fault-slip induced *** 2 is prediction and forecasting of rockburst *** for a rockburst event must tell the location,timing and magnitude of the *** could simply foresee the probability of some of the three *** is extremely challenging to predict rockbursts and large seismic events with current knowledge and technologies,but forecasting is possible,for example the possible locations of strain burst in an underground *** present,the approach using seismic monitoring and numerical modelling is a promising forecasting *** 3 is preconditioning *** current preconditioning methods are blasting,relief-hole drilling and *** fault-slip seismicity is difficult and challenging but has been *** very deep locations(>3000 m),the fracturing could extend from the excavation face to a deep location ahead of the face and therefore preconditioning is usually not *** 4 is dynamic ground support against *** ground support requires that the support system be strong enough to sustain the momentum of the ejecting rock on one hand and tough enough on the other hand to absorb the strain and seismic energies released from the rock *** current dynamic support systems in underground mining are composed of yielding tendons and flexible surface retaining elements like mesh/screen and *** props and engineered timber props are also used for dynamic support.

关键词： Rockburst Seismic event Dynamic ground support Forecasting Preconditioning

xps STUDY ON DIFFERENT CRYSTALLINE FORMS OF COPPER PHTHALOCYANINE

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Chinese Science Bulletin 1985年第5期30卷 612-615页

作者：王殿勋石祖荣 Institute of Chemistry Academia Sinica Beijing Institute of Chemistry Academia Sinica Beijinghe copper phthalocyanine (CuPc) as a dye and photoconductive material plays an important role in bionics. The different crystal forms of CuPc have distinct properties. In this article XPS results of α β γ X-CuPc have been reported. The character of shake-up satellite peaks and valence band spectra in these CuPc compounds was also examined. It was found that the difference of X-CuPc with other crystal forms of CuPc is obvious. XPS study on different crystal forms of CuPc has not been reported previously.

The copper phthalocyanine (CuPc) as a dye and photoconductive material plays an important role in bionics. The different crystal forms of CuPc have distinct properties. In this article xps results of α, β, γ, X-CuPc have been reported. The character of shake-up satellite peaks and valence band spectra in these CuPc compounds was also examined. It was found that the difference of X-CuPc with other crystal forms of CuPc is obvious. xps study on different crystal forms of CuPc has not been reported previously.

关键词： shake phthalocyanine valence photoelectron unsaturated listed Carlson deter sudden 加功

CHARACTERIZATION OF RADIATION CROSSLINKING DENSITY OF POLYSTYRENE WITH THE SHAKE-UP SATELLITE PEAK OF xps

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Chinese Science Bulletin 1985年第6期30卷 750-754页

作者：张万喜孙家珍陈传正岳进 Changchun Institute of Applied Chemistry Academia Sinica Jilin Research Institute of Chemical Engineering Jilin Research Institute of Chemical Engineeringt was well known that the shake-up satellite observed in the X-ray photoelectron spectroscopy (xps) was the results of electron transfer from the highest occupied (HOMO) to the lowest unoccupied orhitals (LUMO) accompanying the direct core-

It was well known that the shake-up satellite observed in the X-ray photoelectron spectroscopy (xps) was the results of electron transfer from the highest occupied (HOMO) to the lowest unoccupied orhitals (LUMO) accom... 详细信息

关键词： shake photoelectron accompanying occupied lowest Probability straight polystyrene irradiation assure