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41.
J. A. Hudson 《Geophysical Journal International》1990,102(2):485-490
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《The Professional geographer》2013,65(4):449-464
During the late 1980s some informal settlements were established within or near affluent Cape Town suburbs. Despite objections by suburban residents that these settlements would lead to a rapid escalation in crime and a dramatic fall in the value of properties, the authorities allowed the settlements to remain. Using data on property transfers, which are then mapped using GIS, the paper examines the effects that the informal settlement of Marconi Beam had on house prices and housing turnover within the adjacent suburb of Milnerton. The results show that most of the objections regarding Marconi Beam's effect on property values were groundless as the settlement had only a negligible effect on property values in the adjacent suburb. 相似文献
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"活地"是宗教的传奇,而由于以往知识与技术的限制以及宗教圣地的"不可侵犯性","活地"也成了大自然的千年未解之谜。通过现场考察和资料调研,明晰了"活地"所在地区的地质构造特征。采用高频率表面波监测、分析技术,通过现场试验,研究了"活地"附近地表浅层岩土体分布情况。采用图像分析技术,经室内试验研究得出了"活地"及周围地区出露岩石的矿物组成。最终,对于"活地"的成因提出以下看法:1.否定了地下深层生长性岩脉诱发"活地"现象的观点;2.膨胀岩及膨胀土吸水膨胀对"活地"的隆升有一定作用,但这不是"活地"的主要诱因;3.提出"活地"是岩石风化作用及特殊地理环境综合作用结果的观点:风化作用使岩体疏松、体积增大,地面隆起;两侧山体运动对其交界处岩石产生挤压作用,为"活地"的持续隆升提供动力源。 相似文献
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Huahua Lü 《世界地质(英文版)》2006,9(1)
In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5% (volume) of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly. 相似文献
47.
The effect of scattering in surface wave tomography 总被引:6,自引:1,他引:6
Jesper Spetzler Jeannot Trampert Roel Snieder 《Geophysical Journal International》2002,149(3):755-767
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Crushed rock subgrade, as one of the roadbed-cooling methods, has been widely used in the Qinghai-Tibet Railway. Much
attention has been paid on the cooling effect of crushed rock; however, the mechanical properties of crushed rock are
somehow neglected. Based on the discrete element method, biaxial compression test condition for crushed rock is compiled
in FISH language in PFC2D, and the natural shape of crushed rock is simulated with super particle "cluster". The effect
of particle size, crushed rock strength and confining pressure level on overall mechanical properties of the crushed
rock aggregate are respectively analyzed. Results show that crushed rock of large particle size plays an essential framework
role, which is mainly responsible for the deformation of crushed rock aggregate. The strength of gravel has a great
influence on overall mechanical properties which means that strength attenuation caused by the freeze thaw cycles cannot
be ignored. The stress-strain curves can be divided into two stages including shear contraction and shear expansion at
different confining pressures. 相似文献