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11.
The security of future supply with natural resources has to comply with objectives towards a sustainable and responsible development. Resources from the geosphere and recycling material from the technosphere may be grouped in a hierarchy the top of which is made up by fossil energy raw materials and of resources from occurrences which were formed by enrichment processes. The base of the hierarchy is made up by bulk raw materials which occur in unlimited amounts in the crust of the Earth and in the sea water and by waste and residues as potential raw materials. Optimising the efficiency of raw materials takes place if material from a lower level substitutes material from a higher level. Highest efficiency is reached if fossil energy from the top of the hierarchy is substituted or consumption is reduced. 相似文献
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P. J. Norton 《Mine Water and the Environment》1982,1(1):17-24
The paper reviews the problems encountered with groundwater in surface mining in Scotland. The problems which occur at various stages of the mining process from initial exploration to mine planning and final restoration are referred to. Special consideration is given to mine drainage and pumping methods. 相似文献
17.
Rheological Properties and Characteristics of Hydraulic Transportation and Heat-Mass Exchange of Coal-Water Fuels 总被引:4,自引:0,他引:4
A. P. Burdukov V. V. Konovalov V. I. Popov V. D. Fedosenko 《Journal of Mining Science》2002,38(3):220-228
The procedure is proposed for calculating the characteristics of flow and heat exchange of coal-water fuels as applied to the pipeline hydraulic transport and heat-mass exchange in the apparatus of ecologically clean combustion in the objects of power engineering. 相似文献
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19.
Conclusions The marked difference between the rates of damping of longitudinal mechanical vibrations in metal rods brought into contact
with specimens of coals and rocks gives grounds for assuming that this phenomenon may be utilized for remote discrimination
between coals and rocks. This makes it possible to develop a special sensor for automatic control of the direction of movement
of heading and extraction machines exactly along the boundary of the coal seam, i.e., along the boundary between the coal
and rock.
Donetsk Polytechnical Institute. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp.
124–128, September–October, 1975. 相似文献
20.