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Aborigines, because of their population numbers and increasing control over land and resources, are crucial to the sustainable development of rural Australia. However, appropriate Aboriginal development requires the replacement of the ‘top‐down’ approaches generally adopted by government agencies by ‘bottom‐up’ approaches reflecting the needs and aspirations of rural Aboriginal people. Past experience demonstrates that Aborigines have faced many frustrations in reconciling these concepts. But some approaches now being adopted in the use and management of Australia's rangelands provide interesting alternatives which may be more generally applicable in enhancing rangeland sustainability. Examples include land‐use practices conducted by Aborigines living in remote homeland centres on their own freehold land, and the diversity of land uses introduced on pastoral stations now under Aboriginal ownership. Broader recognition of the value of these approaches will depend on widespread acknowledgment of the overall worth of Aboriginal land management knowledge in rural restructuring 相似文献
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Compositional characteristics and geodynamic significance of late Miocene volcanic rocks associated with the Chah Zard epithermal gold–silver deposit,southwest Yazd,Iran 下载免费PDF全文
Majid Ghaderi Mohammad Hashem Emami Sebastien Meffre Vadim Kamenetsky Jocelyn McPhie Khin Zaw Rasoul Nasiri Bezenjani 《Island Arc》2018,27(1)
Whole‐rock geochemical and Sr–Nd isotopic data are presented for late Miocene volcanic rocks associated with the Chah Zard epithermal Au–Ag deposit in the Urumieh‐Dokhtar Magmatic Arc (UDMA), Iran, to investigate the magma source, petrogenesis and the geodynamic evolution of the study area. The Chah Zard andesitic to rhyolitic volcanic rocks are characterized by significant Large Ion Lithophile Element (LILE) and Light Rare Earth Element (LREE) enrichment coupled with High Field Strength Element (HFSE) depletion. Our geochemical data indicate an adakitic‐like signature for the volcanic rocks (e.g. SiO2 > 62 wt%, Al2O3 > 15 wt%, MgO < 1.5 wt%, Sr/Y > 70, La/Yb > 35, Yb < 1 ppm, and Y < 18 ppm, and no significant Eu anomalies), distinguishing them from the other volcanic rocks of the UDMA. The Chah Zard volcanic rocks have similar Sr and Nd isotopic compositions; the 87Sr/86Sr(i) ratios range from 0.704 902 to 0.705 093 and the εNd(i) values are from +2.33 to +2.70. However, the rhyolite porphyry represents the final stage of magmatism in the area and has a relatively high 87Sr/86Sr ratio (0.705 811). Our data suggest that the andesitic magmas are from a heterogeneous source and likely to result from partial melting of a metasomatized mantle wedge associated with a mixture of subducted oceanic crust and sediment. These melts subsequently underwent fractional crystallization along with minor amounts of crustal assimilation. Our study is consistent with the model that the volcanic host rocks to epithermal gold mineralization in the UDMA are genetically related to late Miocene Neo‐Tethyan slab break‐off beneath Central Iran. 相似文献
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Laboratory scale study of an industrial phosphate and thermal treatment for polluted dredged sediments 总被引:1,自引:0,他引:1
Souhila KRIBI Jocelyn RAMAROSON Ange NZIHOU Patrick SHARROCK Guy DEPELSENAIRE 《国际泥沙研究》2012,27(4):538-546
Dredged sediments are being chemically treated with phosphoric acid on an industrial scale.The effectiveness of the treatment was evaluated by performing the chemical reaction in a tubular reactor, followed by convective drying and maturation of the treated sediment at ambient temperature and finally thermal destruction of the organic matter by calcinations(500℃-900℃).The influence of acid concentration and calcination temperature on the specific surface area of the sediment was investigated. The stabilization of the heavy metals was evaluated by leaching tests and sequential extraction procedures.The phosphoric acid treatment is effective in reducing heavy metal mobility,a prerequisite for recycling the sediments in various construction materials. 相似文献
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Syed Zahid Husain Stéphane Bélair Jocelyn Mailhot Sylvie Leroyer 《Boundary-Layer Meteorology》2013,147(3):525-551
A new approach to improve the representation of surface processes in the Global Environmental Multiscale (GEM) atmospheric model associated with the exchanges between the urban canopy and the atmosphere is presented. Effects of the urban canopy on the evolution of surface-layer wind, temperature, moisture, and turbulence are directly parametrized in order to allow realistic interactions between the canopy elements (i.e., roofs, roads, and walls) and the atmosphere at GEM’s multiple vertical levels that are positioned inside the canopy. Surface energy budgets as implemented in the Town Energy Balance (TEB) scheme have been used to determine temperatures of the urban canopy elements for the proposed multilayer scheme. Performance of the multilayer scheme is compared against standard implementations of the TEB scheme for one nighttime intensive observation period of the Joint Urban 2003 experiment held in Oklahoma City, USA. Although the new approach is found to have a negligible impact on urban surface-layer wind profiles, it improves the prediction of near-neutral nocturnal profiles of potential temperature close to the surface. The urban heat island effect is simulated with a better accuracy by the multilayer approach. The horizontal temperature gradient across the central business district of the city along the direction of flow is also reasonably well captured by the proposed scheme. 相似文献
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Ismaël Riedel Philippe Guéguen Mauro Dalla Mura Erwan Pathier Thomas Leduc Jocelyn Chanussot 《Natural Hazards》2015,76(2):1111-1141
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Jocelyn Bell Burnell looks back over her first year as President of the Royal Astronomical Society. 相似文献
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