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751.
The way of extraction of insoluble carbonaceous substance (ICS) from black shales and technique of determination of noble metals (NM) in it by direct arc atomic emission analysis (AEA) were developed. The first results are reported on the determination of mineral-bound noble metals in ICS concentrates, which were extracted from the rocks and ores of the Sukhoi Log, Vernyi, Vasil’evskoe, Kuranakh, Daugyztau, Bakyrchik, Kamennoe, El’dorado, and other deposits. 相似文献
752.
753.
Comparison of near-fault and far-fault ground motion effects on geometrically nonlinear earthquake behavior of suspension bridges 总被引:1,自引:1,他引:1
Süleyman Adanur Ahmet Can Altuni?ik Alemdar Bayraktar Mehmet Akk?se 《Natural Hazards》2012,64(1):593-614
This paper presents a comparison of near-fault and far-fault ground motion effects on geometrically nonlinear earthquake behavior of suspension bridges. Bo?azi?i (The First Bosporus) and Fatih Sultan Mehmet (Second Bosporus) suspension bridges built in Istanbul, Turkey, are selected as numerical examples. Both bridges have almost the same span. While Bo?azi?i Suspension Bridge has inclined hangers, Fatih Sultan Mehmet Suspension Bridge has vertical hangers. Geometric nonlinearity including P-delta effects from self-weight of the bridges is taken into account in the determination of the dynamic behavior of the suspension bridges for near-fault and far-fault ground motions. Near-fault and far-fault strong ground motion records, which have approximately identical peak ground accelerations, of 1999 Chi-Chi, 1999 Kocaeli, and 1979 Imperial Valley earthquakes are selected for the analyses. Displacements and internal forces of the bridges are determined using the finite element method including geometric nonlinearity. The displacements and internal forces obtained from the dynamic analyses of suspension bridges subjected to each fault effect are compared with each other. It is clearly seen that near-fault ground motions are more effective than far-fault ground motion on the displacements and internal forces such as bending moment, shear force and axial forces of the suspension bridges. 相似文献
754.
755.
The results of comprehensive geological and metallogenic studies of the Greater Altai are presented. This project has been carried out since 1997 under the guidance of Academician G.N. Shcherba. The importance of these investigations is determined by the need to enhance and further develop mineral resources of nonferrous, noble, rare, and other metals for operating mining and metallurgical enterprises of Kazakhstan. The great body of information on the geology, geophysics, and metallogeny of the region obtained over many years has been integrated on the basis of new global tectonics. The Greater Altai embraces the Hercynides of the Rudny Altai, Qalba-Narym, West Qalba, Zharma-Saur, and the adjacent territories of Russia and China. The present-day tectonic units are considered to be detached blocks of ancient continental massifs that drifted in the Paleoasian ocean and then amalgamated into the structure of the Greater Altai during the Hercynian collision. The tectonic and metallogenic demarcation of the studied territory made possible the recognition of the Rudny Altai, Qalba-Narym, West Qalba, and Zharma-Saur ore belts, different in geology, geodynamic evolution, and metallogeny. The formation conditions and localization of volcanic-hosted massive sulfide, gold, and rare-metal deposits pertaining to certain ore-bearing geochronological levels were specified, and the potential of the region for various mineral resources was estimated. 相似文献
756.
Yu. N. Zanin G. M. Pisareva A. G. Zamirailova V. G. Eder 《Lithology and Mineral Resources》2009,44(3):267-269
Weathering of pyrite in the core recovered from black shales of the Bazhenovo Formation (Upper Jurassic-Lower Cretaceous) in the West Siberian marine basin promoted the successive formation of melanterite (FeSO4 · 7H2O) and szomolnokite (FeSO4 · H2O). Szomolnokite was detected in West Siberia for the first time. 相似文献
757.
Outcrops of the Early Jurassic Navajo Sandstone in southern Utah and northern Arizona, south-western USA are being actively eroded by sand-laden, south-westerly winds. Small-scale stepped topography with risers facing into the wind develops even on steep canyon walls when wind-swept grains strike the rock at a low angle. Photosynthetic, endolithic microbes directly underlie most outcrop surfaces; the crusts formed by these organisms are essential to formation of the small-scale steps. Wind erosion of highlands also forms troughs and pits that are tens of metres across. The pits have deeply scalloped, overhanging walls, and contain central domes surrounded by 'moats' filled with dune sand. Wind erosion of aeolian sandstone is favoured by a positive feedback mechanism in which grains that are liberated from outcrops by impacting particles become a fresh supply of pre-sorted abrasive particles for further attack. 相似文献
758.
P. A. Fokin V. R. Demidova V. M. Yatsenko P. V. Stavinskii O. V. Lisunova 《Moscow University Geology Bulletin》2008,63(5):304-310
Sedimentologic analysis of cores from wells sunk in the Vankor petroleum field allowed refinement of the accumulation conditions producing the sandy strata of the Nizhnyaya Kheta River (Nizhnekhetsky) Formation accumulated in the coastal marine zone and of the Yakovlevo (Yakovlevsky) Formation accumulated under alluvial-deltaic conditions. Petrographic examination of the sandstones added information on the sources, transport, and accumulation conditions of the terrigenous material in the northeastern marginal part of the West Siberian sedimentation basin. 相似文献
759.
A. U. Zaman 《International Journal of Environmental Science and Technology》2013,10(3):455-464
Application and development of municipal solid waste treatment technology depends on various socio-economic and environmental factors. All those factors are work as development drivers for waste management systems. The study aims to identify key drivers from case studies of waste management development trend in Sweden. Social, economic and environmental drivers are identified and presented in this study. The study identifies personal behaviour, local waste management practice, consumption and generation of waste as the key social drivers. Resource value of waste, economic benefit from waste treatment facilities and landfill tax have been acknowledged as economic drivers for developing waste treatment technology. Moreover, global climate change, environmental movement and awareness have been working as environmental drivers for developing various waste treatment methods in Sweden. In addition, the study aims to analyse emerging waste treatment technologies based on a number of literature review and questionnaire survey. Dry composting, pyrolysis-gasification, plasma arc, and anaerobic digestion have been identified as potential emerging technologies for waste management systems in Sweden. 相似文献