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61.
本文对内蒙古林西县北三段银铅多金属矿床矿体的碳、氧、硫、铅同位素进行了测定,并对其成矿物质来源及演化进行了探讨。矿区样品的δ34S‰变化范围为-0.24‰~2.37‰,平均值为1.29‰,初步认为矿石中的硫主要来源于深部岩浆,并有少量生物还原硫的加入。样品的δ13CPDB变化范围为-4.57‰~-7.33‰,平均值为-5.96‰,δ18O为-3.4‰~-4.8‰,平均值为-4.06‰;δ13CPDB-δ18OSMOW关系表明,矿体中的碳可能主要由基性-超基性岩浆提供,并有部分来源于地层,且受大气水影响明显。铅同位素表明北三段矿床的成矿物质可能由造山带物质和地幔物质两部分提供。 相似文献
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The stress produced by repeated train loads decreases with increasing railway subgrade bed depth, and slightly weathered coarse particles of subgrade bed fillings can be broken at different levels under continuous load. Thus, the mass of fine soil, with a diameter of not more than 0.075 mm, is different at different depths. Fine soil is also sensitive to frost heave and thaw settlement. In order to study the effects of non-uniformly distributed fine soil on the mechanical properties of coarse-grained soil of the Shenyang-Dandong Railway, triaxial tests were conducted with three types of specimens, undergoing six freeze-thaw cycle numbers(0, 1, 3, 7, 9, 12) and three confining pressures(100, 200, 300 k Pa). The freezing temperature is-5 °C and the thawing temperature is +15 °C. The stress-strain behavior, static strength, resilient modulus, cohesive force and the angle of internal friction were measured for different tested specimens. As a result, the law of static strength and resilient modulus of different specimens following the increase of freeze-thaw cycles under three confining pressures is obtained. The changing law of cohesive force and friction angle of three specimens following the increase of freeze-thaw cycles is also calculated, and the different results of different specimens are also compared. 相似文献
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锡林浩特国家气候观象台是全区乃至全国观测项目最多、重要性最强的气象台站之一,但在近几年的发展过程中遇到了一些问题。文章重点分析了锡林浩特国家气候观象台观测系统的组成和存在的问题,探讨了推进锡林浩特国家气候观象台观测系统发展的思路。 相似文献
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Release of heavy metals during weathering of the Lower Cambrian Black Shales in western Hunan,China 总被引:8,自引:0,他引:8
Bo?PengEmail author Zhaoliang?Song Xiangling?Tu Meilian?Xiao Fucheng?Wu Huanzhe?Lv 《Environmental Geology》2004,45(8):1137-1147
Weathering of heavy metal enriched black shales may be one of the most important sources of environmental contamination in areas where black shales are distributed. Heavy metal release during weathering of the Lower Cambrian Black Shales (LCBS) in western Hunan, China, was investigated using traditional geochemical methods and the ICP-MS analytical technique. Concentrations of 16 heavy metals, 8 trace elements and P were measured for samples from selected weathering profiles at the Taiping vanadium ore mine (TP), the Matian phosphorous ore mine (MT), and Taojiang stone-coal mine (TJ). The results show that the bedrock at these three profiles is enriched with Sc, V, Cr, Co, Ni, Cu, Zn, Pb, Th, U, Mo, Cd, Sb, Tl, and P. Based on mass-balance calculation, the percentages of heavy metals released (in % loss) relative to immobile element Nb were estimated. The results show significant rates of release during weathering of: V, Cr, Co, Ni, Cu, Zn, U, Mo, Cd, Sn, Sb, and Tl for the TP profile; Sc, Cr, Mn, Co, Ni, Cu, Zn, Pb, Th, Cd, and Sn for the MT profile; and Sc, Mn, Co, Ni, Zn, Th, Cd, Sn, and Tl for the TJ profile. Among these heavy metals, Co, Ni, Zn, Cd, and Sn show very similar features of release from each of the three weathering profiles. The heavy metals released during weathering may affect the environment (especially topsoil and surface waters) and are possibly related to an observed high incidence of endemic diseases in the area. 相似文献
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质子化壳聚糖吸附除磷效能研究 总被引:1,自引:0,他引:1
本研究通过质子化方法强化壳聚糖的除磷效果,研究壳聚糖的质子化度、吸附时间、磷的存在形态等因素对质子化壳聚糖除磷效果的影响,结果表明,壳聚糖对水中总磷及磷酸根的吸附效果随着其质子化度的升高而呈现明显加强的趋势;质子化壳聚糖对水中总磷的吸附量随着时间的延长而增加,吸附时间在70-80min时达到最大吸附量;水溶液中磷的存在形态,影响质子化壳聚糖的除磷效果。 相似文献
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基于锡尔系数的广东省城市创新能力差异研究 总被引:2,自引:0,他引:2
运用锡尔系数的方法,以专利授权数为变量,通过GDP和人口数2种不同的比重加权方法对比,对广东省各城市间的城市创新能力进行测算并分析其差异。研究表明:以GDP比重加权的城市创新能力差异呈减小趋势,而以人口数比重加权的创新能力差异呈增大趋势;城市越来越重视城市创新的建设,以创新带动城市发展;人口增长速度与城市创新能力有一定的关联,是造成城市创新能力差异的重要原因。 相似文献
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