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An assessment of coal pillar system stability criteria based on a mechanistic evaluation of the interaction between coal pillars and the overburden

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International Journal of Mining Science and Technology 2017年第1期27卷 9-15页

作者： Reed Guy Mctyer Kent Frith Russell mine advice pry ltd NewcastleNSW 2322Australia

Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assigned based on past mining experience or a statistical link between Fo S and probability of failure(Po F). Pillar width-to-height(w/h) ratio has long been established as having a material influence on both pillar strength and its potential failure mode. However, there has been significant disagreement on using both factor of safety(Fo S) and w/h as part of pillar system stability criterion, as compared to using Fo S in isolation. This paper will argue that there are valid technical reasons to bring w/h ratio into system stability criteria(other than its influence on pillar strength), as it is related to the post-failure stiffness of the pillar, as measured in situ, and its interaction with overburden stiffness. When overburden stiffness is also brought into pillar system stability considerations, two issues emerge. The first is the width-todepth(W/D) ratio of the panel and whether it is sub-critical or super-critical from a surface subsidence perspective. The second relates to a re-evaluation of pillar Fo S based on whether the pillar is in an elastic or non-elastic(i.e., post-yield) state in its as-designed condition, as this is relevant to maintaining overburden stiffness at the highest possible level. The significance of the model is the potential to maximise both reserve recovery and mining efficiencies without any discernible increase in geotechnical risk, particularly in thick seams and higher depth of cover mining situations. At a time when mining economics are, at best, marginal, removing potentially unnecessary design conservatism is of interest to all mine operators and is an important topic for discussion amongst the geotechnical community.

关键词： Coa] pillars Stability Overburden Post-failure behaviour Stability criteria

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Regional tectonics, geology, magma chamber processes and mineralisation of the Jinchuan nickel-copper-PGE deposit, Gansu Province, China： A review

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Geoscience Frontiers 2016年第3期7卷 431-451页

作者： T.M. (Mike) Porter Porter GeoConsultancy pry ltd. Linden Park 5065 SA Australia

The Jinchuan Ni-Cu-PGE deposit（〉500 Mt @1.2%Ni,0.7%Cu,～0.4 g/t PGE）,one of the largest magmatic sulphide deposits in the world,is located within the westernmost terrane of the North China *** is hosted within the 6.5 km long,Neoproterozoic（～0.83 Ga） Jinchuan ultramafic intrusion,emplaced as a sill-like body into a Palaeoproterozoic suite of gneisses,migmatites,marbles and amphibolites,below an active intracratonic *** parental magma was high-Mg basalt,generated through melting of subcrustal lithospheric mantle by a mantle plume during the initiation of Rodinia supercontinent *** lower Palaeozoic collision of the exotic Qilian Block with the breakup-related southern margin of the craton accreted a subduction complex,and emplaced voluminous granitic intrusions and foreland basin sequences within the craton,to as far north as *** the Cainozoic,allochthonous lower Palaeozoic rocks were thrust up to 300 km to the northeast over cratonic basement,to within 25 km of the Jinchuan *** Jinchuan ultramafic intrusion was injected into three interconnected sub-chambers,each containing a separate *** essentially comprises an olivine-orthopyroxene-chromite cumulate,with interstitial orthopyroxene,clinopyroxene,plagioclase and phlogopite,and is predominantly composed of lherzolite（～80%）,with an outer rim of olivine pyroxenite and cores of mineralised *** occurs as disseminated and net-textured sulphides,predominantly within the dunite,with lesser,PGE rich lenses,late massive sulphide accumulations,small copper rich pods and limited mineralised diopside skarn in wall rock *** principal ore minerals are pyrrhotite（the dominant sulphide）,pentlandite,chalcopyrite,cubanite,mackinawite and pyrite,with a variety of platinum group minerals and minor *** deposit underwent significant post-magmatic tremolite-actinolite,chlorite,serpentine and magnetite *** volume of thejinchuan intrusion accounts for 〈3%

关键词： Rodinia break-up rifting Plume related Deep staging chamber Olivine-orthopyroxene-chromite cumulate Net textured and disseminated sulphides Post-magmatic alteration

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A combined 2D and 3D numerical modeling approach to provide adequate roof support in complex 3D excavations

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International Journal of Mining Science and Technology 2016年第1期26卷 169-174页

作者： Heritage Yvette Stemp Craig SCT Operations pry ltd. Wollongong NSW 2500 Australia

Traditional methods for assessing effective roof support can be difficult to apply to complex three-dimensional excavations. Through worked examples,the approach of combined two-dimensional and three-dimensional numerical modeling has been shown to be successful in understanding mechanisms of rock failure for unique excavation geometries and geotechnical properties and,in turn,provides adequate roof support recommendations for complex three-dimensional excavations in Australian coal mines. An interactive approach of monitoring and model review during the excavation process is an important part of model support recommendations to ensure rock failure and deformation in the model are representative of actual conditions,to provide effective and practical controls.

关键词： 3D numerical modelingUnderground excavationsRoof supportRock failureUnderground storage bin

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Design of primary ground support during roadway development using empirical databases

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International Journal of Mining Science and Technology 2016年第1期26卷 131-137页

作者： Ry Stone Colder Associates pry ltd.. Newcastle NSW 2300 Australia

There have been many design practices utilised within the coal mining industry to arrive at the minimum densities of primary ground support required during roadway development. This paper demonstrates the practical use of empirical databases, and focuses on the main drivers for ground support as demonstrated in conceptual models. （;older Associates＇ empirical databases used for ground support include a primary roof support database and a primary fib support database. Both are based on successful ground support designs installed in mines in Australia, the US, the LIK, South Africa, New Zealand, and Europe. The term ＂successful＂ refers to those designs that were used on a repeated basis for the purpose of roadway devel- opment. The primary roof support database indicates that the major factors influencing successful roof support designs are roof competency, expressed as the coal mine roof rating （CMRR）, and in situ stress. In regard to the primary rib support database, it is evident from the current database that the primary factors affecting the capacity of rib support required for a successful design are roadway height and depth of cover. These databases have been used to help determine the minimum primary ground support designs required at many mine sites in Australasia, Europe, and the US. This paper will demonstrate the effectiveness and practicality of these databases at two selected mines in Australia and the US. In order to improve the primary rib support database, this paper will also propose a new rib deformation rating based on the addition of site specific coal strength data for the Australian mines. The proposed rat- ing attempts to capture the main variables that define the behaviour of a buckling column.

关键词： Roof supportRib supportEmpirical databaseCoal miningGeotechnical engineering

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Performance of a Curtainwall in the Magnitude 6.3 Christchurch Earthquake of February 22, 2011

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Journal of Civil Engineering and Architecture 2016年第12期10卷 1344-1354页

作者： Peter Lalas Janus Facades pry ltd Sydney 2019 Australia

On February 22,2011, Christchurch in New Zealand experienced a magnitude 6.3 earthquake which devastated many of the buildings in the city, especially those made of masonry construction. Janus Facades was asked to inspect the facade of a fourteen storey building which had a curtainwall-clad tower and granite and tile cladding on the three storey podium. The unitised curtainwall was not well designed. It did not have adequately sized joints in accordance with industry standards to absorb seismic effects and it was never really weathertight. Most of the damage to the curtainwall was caused by the damaged structure. Damage to the structure and internal fittings was also observed.

关键词： Curtainwall. earthquake seismic capability moveable joints.

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Creed vs. Greed- The Philosophy of Management

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Chinese Business Review 2011年第9期10卷 783-789页

作者： Melville Miranda Shruti Mahajan Australian Education Academy pry ltd. Melbourne Australia

Creed is ＂a system of Christian or other religious belief; a faith There is no doubt that business is about making financial profit, and that is the way it should be. However, it is also important to understand that a person＇s creed-their principles and beliefs-has a tremendous influence on the way in which they will practice business. In recent decades, for example, the fraudulent business practices of major corporations such as Adelphia, Enron, Dynergy, Global Crossing, Merrill Lynch, Qwest, Tyco, and WorldCom, became international news. One after one, major world businesses, which were widely trusted and respected, toppled, leaving in their quake millions of ruined lives. Seemingly respectable and successful business practices were guilty of behaving with criminal intentions; consequently appearing, in the opinion of many observers, little more than common thieves As such, the philosophy of management, especially in relation to Creed vs. Greed, has become increasingly important within today＇s business world.

关键词： profit religion management business corporate social responsibility

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MANAGING YOUR COPPER HEAP LEACH/SOLVENT EXTRACTION/ELECTROWINNING OPERATION, AND HOW TO MINIMISE THE RISK OF LEACH PROBLEMS AFFECTING COPPER PRODUCTION

MANAGING YOUR COPPER HEAP LEACH/SOLVENT EXTRACTION/ELECTROWI...

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21世纪重有色金属冶金高新技术及新材料国际会议

作者： Philip Crane Cognis Australia pry ltd Broadmeadows VIC 3047 Australia

The copper solvent extraction process has been successfully employed for over thirty years to recover copper from low-grade oxide and low-grade sulphide ores. Experience has shown that the key to a successful project is to ensure that the heap or dump leach operates efficiently. This paper discusses some of the leaching factors that can adversely affect a leach / solvent extraction / electrowinning project and suggests some remedies that can be instituted in the solvent extraction plant to compensate whilst solutions to the leaching problems are being sought.

关键词： PLS LEACH MANAGING YOUR COPPER HEAP LEACH/SOLVENT EXTRACTION/ELECTROWINNING OPERATION AND HOW TO MINIMISE THE RISK OF LEACH PROBLEMS AFFECTING COPPER PRODUCTION

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Land Use Change and Anthropogenic Driving Forces:A Case Study in Yanhe River Basin

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Chinese Geographical Science 2011年第5期21卷 587-599页

作者： SU Changhong FU Bojie LU Yihe LU Nan ZENG Yuan HE Anna Halina LAMPARSKI State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China ENV Australia pry ltd 113 Hamersley Road Subiaco Perth 6008 Australia

Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction.

关键词： land use landscape metrics anthropogenic driving force Grain for Green (GfG) policy Yanhe River Basin

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Developing Wheat for Improved Yield and Adaptation Under a Changing Climate： Optimization of a Few Key Genes

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Engineering 2018年第4期4卷 514-522页

作者： M.A.N. Nazim Ud Dowl Ian Edwards Graham O'Hara Shahidul Islam Wujun Ma School of Veterinary and Life Sciences Murdoch University Perth WA 6150 Australia Edstar Genetics pry. ltd. Perth WA 6150 Australia

Wheat grown under rain-fed conditions is often affected by drought worldwide. Future projections from a climate simulation model predict that the combined effects of increasing temperature and changing rainfall patterns will aggravate this drought scenario and may significantly reduce wheat yields unless appropriate varieties are adopted. Wheat is adapted to a wide range of environments due to the diversity in its phenology genes. Wheat phenology offers the opportunity to fight against drought by modifying crop developmental phases according to water availability in target environments. This review summa- rizes recent advances in wheat phenology research, including vernalization （Vrn）, photoperiod （Ppd）, and also dwarfing （Rht） genes. The alleles, haplotypes, and copy number variation identified for Vrn and Ppd genes respond differently in different climatic conditions, and thus could alter not only the development phases but also the yield. Compared with the model plant Arabidopsis, more phenology genes have not yet been identified in wheat; quantifying their effects in target environments would benefit the breeding of wheat for improved drought tolerance. Hence, there is scope to maximize yields in water-limited envi-ronments by deploying appropriate phenology gene combinations along with Rht genes and other important physiological traits that are associated with drought resistance.

关键词： Phenology Wheat Vernalization Photoperiod Drought Climate change

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Acetylsalicylic acid supplementation improves protein utilization efficiency while vitamin E supplementation reduces markers of the inflammatory response in weaned pigs challenged with enterotoxigenic ***

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Journal of Animal Science and Biotechnology 2017年第1期8卷 143-153页

作者： Jae Cheol Kim Bruce P. Mullan John L. Black Robert J. E. Hewitt Robert J. van Barneveld John R. Pluske School of Veterinary and Life Sciences Murdoch University Murdoch WA 6150 Australia Department of Agriculture and Food Pork Innovation South Perth WA 6151 Australia John L Black Consulting Warrimoo NSW 2774 Australia SunPork Farms Solutions Loganholme QLD 4129 Australia Barneveld Nutrition pry ltd Loganholme QLD 4129 Australia

Background： This experiment was conducted to test the hypothesis that vitamin E（Vit E） and acetylsalicylic acid（ASA）, a cyclooxygenase-2（COX-2） inhibitor, will additively reduce the production of the immunosuppressive molecule prostaglandin E_2（PGE_2） and hence reduce inflammatory responses in weaner pigs experimentally infected with an enterotoxigenic strain of E. ***： The experiment was conducted in a research facility with 192 individually-housed male weaner pigs（Landrace × Large White） weighing 6.6 ± 0.04 kg（mean ± SEM）. The pigs were experimentally infected with an enterotoxigenic strain of E. coli and were allocated to a 2 × 3 factorial design with the respective factors being without and with 125 ppm ASA and three levels of Vit E supplementation（50, 100 or 200 IU/kg diet, dl-α-tocopheryl acetate）.Results： Acetylsalicylic acid supplementation improved average daily gain（P 〈 0.05） and tended to improve feed：gain ratio（P 〈 0.10） during the first 14 d after weaning. Acetylsalicylic acid supplementation also improved（P 〈 0.001） amino acid utilization efficiency（as assessed by plasma urea level） and tended to decrease（P 〈 0.10） PGE2 production in the liver without affecting smal intestinal histology and tight junction protein mR NA expression in the jejunal epithelium. Vitamin E supplementation greater than 100 IU/kg diet sustained both the plasma Vit E concentration（P 〈 0.001） and plasma haptoglobin content（P 〈 0.001） after weaning. However, there was no additive effects of the combined supplementation of ASA and Vit E on performance, intestinal barrier function and inflammatory responses of weaned ***： Although ASA and vitamin E improved amino acid utilization efficiency and reduced acute inflammatory responses, ASA and vitamin E did not additively reduce production of PGE2 and inflammatory responses in weaner pigs experimental y infected with an enterotoxigenic strain of E. coli.

关键词： Acetylsalicylic acid E.coli infection PGE_2 Vitamin E Weaner pigs

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